1,643 results on '"Cobb IN"'
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2. A Novel Bio-Adhesive Mesh System for Medical Implant Applications: In Vivo Assessment in a Rabbit Model
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Melinda Harman, Kevin Champaigne, William Cobb, Xinyue Lu, Varun Chawla, Liying Wei, Igor Luzinov, O. Thompson Mefford, and Jiro Nagatomi
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poloxamine hydrogel adhesive ,“grafting to” surface modification ,polymer brushes ,polypropylene ,surgical mesh ,in vivo animal model ,Science ,Chemistry ,QD1-999 ,Inorganic chemistry ,QD146-197 ,General. Including alchemy ,QD1-65 - Abstract
Injectable surgical sealants and adhesives, such as biologically derived fibrin gels and synthetic hydrogels, are widely used in medical products. While such products adequately adhere to blood proteins and tissue amines, they have poor adhesion with polymer biomaterials used in medical implants. To address these shortcomings, we developed a novel bio-adhesive mesh system utilizing the combined application of two patented technologies: a bifunctional poloxamine hydrogel adhesive and a surface modification technique that provides a poly-glycidyl methacrylate (PGMA) layer grafted with human serum albumin (HSA) to form a highly adhesive protein surface on polymer biomaterials. Our initial in vitro tests confirmed significantly improved adhesive strength for PGMA/HSA grafted polypropylene mesh fixed with the hydrogel adhesive compared to unmodified mesh. Toward the development of our bio-adhesive mesh system for abdominal hernia repair, we evaluated its surgical utility and in vivo performance in a rabbit model with retromuscular repair mimicking the totally extra-peritoneal surgical technique used in humans. We assessed mesh slippage/contraction using gross assessment and imaging, mesh fixation using tensile mechanical testing, and biocompatibility using histology. Compared to polypropylene mesh fixed with fibrin sealant, our bio-adhesive mesh system exhibited superior fixation without the gross bunching or distortion that was observed in the majority (80%) of the fibrin-fixed polypropylene mesh. This was evidenced by tissue integration within the bio-adhesive mesh pores after 42 days of implantation and adhesive strength sufficient to withstand the physiological forces expected in hernia repair applications. These results support the combined use of PGMA/HSA grafted polypropylene and bifunctional poloxamine hydrogel adhesive for medical implant applications.
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- 2023
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3. Editorial: Peptidomimetics: Synthetic Tools for Drug Discovery and Development
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Annarita Del Gatto, Steven L. Cobb, Jinqiang Zhang, and Laura Zaccaro
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peptidomimetics ,design ,chemical synthesis ,structure-activity relationship ,drug discovery ,drug development ,Chemistry ,QD1-999 - Published
- 2021
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4. Cobb's Red Cabbage Indicator.
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Cobb, Vicki
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Describes the use of an indicator made from the pigment in red cabbage. Cabbage is grated then soaked in water. When the water is a strong red, the cabbage is strained out. The cabbage-juice indicator is then used to test for acids and bases. Includes a list of good foods to test for acidity and alkalinity. (PVD)
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- 1998
5. Bio-Electrocatalytic Conversion of Food Waste to Ethylene via Succinic Acid as the Central Intermediate
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Pichler, CM, Bhattacharjee, S, Lam, E, Su, L, Collauto, A, Roessler, MM, Cobb, SJ, Badiani, VM, Rahaman, M, Reisner, E, Pichler, CM [0000-0001-7686-7215], Lam, E [0000-0002-8641-7928], Su, L [0000-0001-8784-3120], Roessler, MM [0000-0002-5291-4328], Cobb, SJ [0000-0001-5015-8090], Badiani, VM [0000-0002-3867-6714], Rahaman, M [0000-0002-8422-0566], Reisner, E [0000-0002-7781-1616], Apollo - University of Cambridge Repository, and Engineering & Physical Science Research Council (EPSRC)
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Science & Technology ,Chemistry, Physical ,circular economy ,0904 Chemical Engineering ,decarboxylation reaction ,General Chemistry ,bio-electrochemistry ,0305 Organic Chemistry ,ethylene production ,Catalysis ,BIOMASS ,sustainable resources ,ENERGY ,Chemistry ,GAS ,Physical Sciences ,KEYWORDS ,IRRADIATED SINGLE-CRYSTALS ,RADICALS ,ELECTRON-SPIN-RESONANCE ,0302 Inorganic Chemistry ,waste conversion ,DIOXIDE ,ESR - Abstract
Ethylene is an important feedstock in the chemical industry, but currently requires production from fossil resources. The electrocatalytic oxidative decarboxylation of succinic acid offers in principle an environmentally friendly route to generate ethylene. Here, a detailed investigation of the role of different carbon electrode materials and characteristics revealed that a flat electrode surface and high ordering of the carbon material are conducive for the reaction. A range of electrochemical and spectroscopic approaches such as Koutecky-Levich analysis, rotating ring-disk electrode (RRDE) studies, and Tafel analysis as well as quantum chemical calculations, electron paramagnetic resonance (EPR), and in situ infrared (IR) spectroscopy generated further insights into the mechanism of the overall process. A distinct reaction intermediate was detected, and the decarboxylation onset potential was determined to be 2.2-2.3 V versus the reversible hydrogen electrode (RHE). Following the mechanistic studies and electrode optimization, a two-step bio-electrochemical process was established for ethylene production using succinic acid sourced from food waste. The initial step of this integrated process involves microbial hydrolysis/fermentation of food waste into aqueous solutions containing succinic acid (0.3 M; 3.75 mmol per g bakery waste). The second step is the electro-oxidation of the obtained intermediate succinic acid to ethylene using a flow setup at room temperature, with a productivity of 0.4-1 μmol ethylene cmelectrode -2 h-1. This approach provides an alternative strategy to produce ethylene from food waste under ambient conditions using renewable energy.
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- 2022
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6. Ultrafast transient absorption spectroelectrochemistry: femtosecond to nanosecond excited-state relaxation dynamics of the individual components of an anthraquinone redox couple
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Sofia Goia, Matthew A. P. Turner, Jack M. Woolley, Michael D. Horbury, Alexandra J. Borrill, Joshua J. Tully, Samuel J. Cobb, Michael Staniforth, Nicholas D. M. Hine, Adam Burriss, Julie V. Macpherson, Ben R. Robinson, Vasilios G. Stavros, Goia, Sofia [0000-0002-4492-0410], Woolley, Jack M [0000-0002-3893-3880], Horbury, Michael D [0000-0001-8235-8142], Borrill, Alexandra J [0000-0001-5495-0181], Tully, Joshua J [0000-0002-9584-0437], Cobb, Samuel [0000-0001-5015-8090], Hine, Nicholas DM [0000-0001-5613-3679], Macpherson, Julie V [0000-0002-4249-8383], Stavros, Vasilios G [0000-0002-6828-958X], Apollo - University of Cambridge Repository, and Cobb, Samuel J [0000-0001-5015-8090]
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Chemistry ,34 Chemical Sciences ,Redox-active species ,3406 Physical Chemistry ,Transient Electronic Absorption Spectroscopy ,QD ,General Chemistry ,Spectroelectrochemistry ,QC - Abstract
Many photoactivated processes involve a change in oxidation state during the reaction pathway and formation of highly reactive photoactivated species. Isolating these reactive species and studying their early-stage femtosecond to nanosecond (fs–ns) photodynamics can be challenging. Here we introduce a combined ultrafast transient absorption-spectroelectrochemistry (TA-SEC) approach using freestanding boron doped diamond (BDD) mesh electrodes, which also extends the time domain of conventional spectrochemical measurements. The BDD electrodes offer a wide solvent window, low background currents, and a tuneable mesh size which minimises light scattering from the electrode itself. Importantly, reactive intermediates are generated electrochemically, via oxidation/reduction of the starting stable species, enabling their dynamic interrogation using ultrafast TA-SEC, through which the early stages of the photoinduced relaxation mechanisms are elucidated. As a model system, we investigate the ultrafast spectroscopy of both anthraquinone-2-sulfonate (AQS) and its less stable counterpart, anthrahydroquinone-2-sulfonate (AH2QS). This is achieved by generating AH2QS in situ from AQS via electrochemical means, whilst simultaneously probing the associated early-stage photoinduced dynamical processes. Using this approach we unravel the relaxation mechanisms occurring in the first 2.5 ns, following absorption of ultraviolet radiation; for AQS as an extension to previous studies, and for the first time for AH2QS. AQS relaxation occurs via formation of triplet states, with some of these states interacting with the buffered solution to form a transient species within approximately 600 ps. In contrast, all AH2QS undergoes excited-state single proton transfer with the buffered solution, resulting in formation of ground state AHQS− within approximately 150 ps., A spectroelectrochemical set-up using a boron doped diamond mesh electrode is presented; from ultrafast photodynamics to steady-state, the photochemistry and photophysics of redox active species and their reactive intermediates can be investigated.
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- 2022
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7. Gene Expression of Agronomically Important Secondary Metabolites in cv. ‘USDA Cascade’ Hop (Humulus lupulus L.) Cones during Critical Developmental Stages
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John A. Henning, Lillian K. Padgitt-Cobb, David A. Hendrix, Renée L. Eriksen, and Angela M. Randazzo
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Bract ,Humulus lupulus ,biology ,food and beverages ,Cascade hop ,biology.organism_classification ,Applied Microbiology and Biotechnology ,Hop (networking) ,Transcriptome ,chemistry.chemical_compound ,chemistry ,Gene expression ,Xanthohumol ,Botany ,Food Science ,Biotechnology - Abstract
The transcriptome from lupulin glands and associated bracts from cone tissue of hop (Humulus lupulus) c.v. ‘Cascade’, during three stages of development: early, mid, and late or near-harvest, was s...
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- 2021
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8. Toward Rational Design of Electrogenerated Molecularly Imprinted Polymers (eMIPs): Maximizing Monomer/Template Affinity
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Caitlin G. Bresnahan, Jared S. Cobb, Matthew W. Glasscott, Garrett W. George, Timothy C. Schutt, Erik M. Alberts, Gilbert K. Kosgei, Lee C. Moores, and P. U. Ashvin Iresh Fernando
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chemistry.chemical_compound ,Monomer ,Materials science ,Polymers and Plastics ,chemistry ,Process Chemistry and Technology ,Organic Chemistry ,Molecularly imprinted polymer ,Rational design ,Combinatorial chemistry - Published
- 2021
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9. Enantioselective Organocatalytic Synthesis of Bicyclic Resorcinols via an Intramolecular Friedel−Crafts‐Type 1,4‐Addition: Access to Cannabidiol Analogues
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Alexander J. A. Cobb, Kenneth Shankland, Callum D Johnston, Nicholas R. Lees, Laura A Bryant, and Hannah Straker
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Bicyclic molecule ,Silylation ,Chemistry ,Intramolecular force ,Organocatalysis ,Michael reaction ,Enantioselective synthesis ,Organic chemistry ,General Chemistry ,Protecting group ,Friedel–Crafts reaction - Abstract
The organocatalytic transformation of resorcinols is extremely rare. In this article, we report a highly enantioselective, organocatalytic intramolecular cyclization of these systems by a Friedel-Crafts-type 1,4-addition using a Jorgensen-Hayashi-like organocatalyst with a large silyl protecting group, and show that heat improves reaction yield with virtually no detriment to enantioselectivity. A variety of bicyclic resorcinols were obtained with excellent enantioselectivities (up to 94%). To show the utility of these constructs, and as part of a wider project involving the synthesis of cannabinoid-like compounds, the resorcinol formed was used to generate both 'normal' and 'abnormal' cannabidiol (CBD) derivatives which were shown to have anticonvulsant activity.
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- 2021
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10. Transvenous lead extraction on uninterrupted anticoagulation: A safe approach?
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Hunter Ross, Sporton Simon, Sawhney Vinit, Cobb Vanessa, Lambiase Pier, Baca Luisa, Earley Mark, Dhinoja Mehul, Breitenstein Alexander, Lowe Martin, Ezzat Vivienne, Chow Anthony, Steffel Jan, Whittaker-Axon Sarah, and Schilling Richard
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Inotrope ,030204 cardiovascular system & hematology ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,Multicentre registry ,Physiology (medical) ,Clinical endpoint ,Medicine ,Diseases of the circulatory (Cardiovascular) system ,030212 general & internal medicine ,Lead (electronics) ,Creatinine ,Proportional hazards model ,business.industry ,Transvenous lead extraction ,Warfarin ,Transvenous lead ,chemistry ,Uninterrupted anticoagulation ,Anesthesia ,RC666-701 ,Original Article ,Tamponade ,Cardiology and Cardiovascular Medicine ,business ,medicine.drug - Abstract
Introduction Current guidelines advocate reviewing peri-procedural anticoagulation on individual case basis for transvenous lead extraction (TLE). We investigated the safety of TLE on uninterrupted warfarin with therapeutic INR. Methods Retrospective registry of consecutive patients undergoing TLE on uninterrupted warfarin (Warfarin Group) across two centres. Age and sex matched controls not on anticoagulation (No-Warfarin Group) and undergoing TLE over the same time-period were included. Both groups were compared over one-year. Results 121 TLEs over 18-months. 22 patients on uninterrupted anticoagulation were compared to 22 controls. Groups were well matched for baseline demographics other than INR. Warfarin group had mean INR of 2.2 ± 0.6 (range 2–3.5). Primary end point was procedural safety and efficacy. Amongst cases, 43/45 (96%) leads were removed in their entirety compared to 37/40 (93%) in controls (p = 0.66). In the cases, these included 44% defibrillator, 47% pace-sense and 9% CS leads of average duration 7yrs. There was no reported tamponade, haemothorax or procedural mortality in either group. One patient amongst cases required inotropic support while two patients amongst controls had device-site haematomas. No significant difference reported in Hb drop post-procedure or overall complication rate between the groups (p = 0.11,0.32). Cox regression showed a significant association between procedural success and device infection, number of leads extracted, serum creatinine (p = 0.03, 0.04, 0.02). Over a 1-year follow-up, there was lead displacement in one case and one control had infection of the re-implanted device. Conclusion TLE can be carried out safely in anticoagulated patients with therapeutic INRs. Larger multicentre studies are required to confirm these findings.
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- 2021
11. Pembrolizumab alone or combined with chemotherapy versus chemotherapy as first-line therapy for advanced urothelial carcinoma (KEYNOTE-361): a randomised, open-label, phase 3 trial
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Thomas Powles, Tibor Csőszi, Mustafa Özgüroğlu, Nobuaki Matsubara, Lajos Géczi, Susanna Y-S Cheng, Yves Fradet, Stephane Oudard, Christof Vulsteke, Rafael Morales Barrera, Aude Fléchon, Seyda Gunduz, Yohann Loriot, Alejo Rodriguez-Vida, Ronac Mamtani, Evan Y Yu, Kijoeng Nam, Kentaro Imai, Blanca Homet Moreno, Ajjai Alva, Diana Vera Cascallar, Mirta Varela, Mauricio Fernandez Lazzaro, Diego Lucas Kaen, Gabriela Gatica, David Hugo Flores, Agustin Falco, Matias Molina, Filip Van Aelst, Brieuc Sautois, Jean-Pascal Machiels, Denis Schallier, Leandro Brust, Liane Rapatoni, Sergio J Azevedo, Gisele Marinho, Joao Paulo Holanda Soares, Carlos Dzik, Jamile Almeida Silva, Andre Poisl Fay, Joel Gingerich, Cristiano Ferrario, Kylea Potvin, Marie Vanhuyse, Mahmoud Abdelsalam, Susanna Cheng, Christian Caglevic, Felipe Reyes, Jose Luis Leal, Francisco Francisco, Carolina Ibanez, Florence Joly, Brigitte Laguerre, Sylvain Ladoire, Aude Flechon, Delphine Topart, Olivier Huillard, Stéphane Oudard, Marine Gross-Goupil, Stephane Culine, Gwenaelle Gravis, Peter Reichardt, Margitta Retz, Jan Herden, David Pfister, Carsten Ohlman, Michael Stoeckle, Manfred Wirth, Anja Lorch, Guenter Niegisch, Peter J Goebell, Martin Boegemann, Axel Merseburger, Georgios Gakis, Jens Bedke, Andreas Neisius, Christian Thomas, Thomas Hoefner, Andras Telekes, Judit Erzsebet Kosa, Janos Revesz, Gyorgy Bodoky, Tibor Csoszi, Andras Csejtei, Lajos Geczi, Agnes Ruzsa, Zsuzsanna Kolonics, Jozsef Erfan, Ray McDermott, Richard Bambury, Avishay Sella, Stephen Jay Frank, Daniel Kejzman, Olesya Goldman, Eli Rosenbaum, Avivit Peer, Raanan Berger, Keren Rouvinov, David Sarid, Satoshi Fukasawa, Gaku Arai, Akito Yamaguchi, Akira Yokomizo, Tatsuya Takayama, Hidefumi Kinoshita, Eiji Kikuchi, Ryuichi Mizuno, Yasuhisa Fujii, Naoto Sassa, Yoshihisa Matsukawa, Kiyohide Fujimoto, Toshiki Tanikawa, Yoshihiko Tomita, Kazuo Nishimura, Masao Tsujihata, Masafumi Oyama, Naoya Masumori, Hiroomi Kanayama, Toshimi Takano, Yuji Miura, Jun Miyazaki, Akira Joraku, Tomokazu Kimura, Yoshiaki Yamamoto, Kazuki Kobayashi, Ronald De Wit, Maureen Aarts, Winald Gerritsen, Maartje Los, Laurens Beerepoot, Adel Izmailov, Sergey Igorevich Gorelov, Boris Yakovlevich Alekseev, Andrey Semenov, Vladimir Anatolyevich Kostorov, Sergey M Alekseev, Alexander Zyryanov, Vasiliy Nikolaevich Oschepkov, Vladimir Aleksandrovich Shidin, Vladimir Ivanovich Vladimirov, Rustem Airatovich Gafanov, Petr Alexandrovich Karlov, David Brian Anderson, Lucinda Shepherd, Graham Lawrence Cohen, Bernardo Louis Rapoport, Paul Ruff, Nari Lee, Woo Kyun Bae, Hyo Jin Lee, Urbano Anido Herranz, Enrique Grande, Teresa Alonso Gordoa, Josep Guma Padro, Daniel Castellano Gauna, Jose Angel Arranz, Jose Munoz Langa, Regina Girones Sarrio, Alvaro Montesa Pino, Maria Jose Juan Fita, Yu-Li Su, Yung-Chang Lin, Wen-Pin Su, Ying-Chun Shen, Yen-Hwa Chang, Yi-Hsiu Huang, Virote Sriuranpong, Phichai Chansriwong, Vichien Srimuninnimit, Pongwut Danchaivijitr, Huseyin Abali, Sinan Yavuz, Ozgur Ozyilkan, Mehmet Ali Nahit Sendur, Meltem Ekenel, Mustafa Ozguroglu, Cagatay Arslan, Mustafa Ozdogan, Alison Birtle, Robert Huddart, Maria de Santis, Anjali Zarkar, Linda Evans, Syed Hussain, Christopher DiSimone, Antonio F Muina, Peter Schlegel, Haresh S Jhangiani, Michael Harrison, Dennis E Slater, David Wright, Ivor J Percent, Jianqing Lin, Clara Hwang, Sumati Gupta, Madhuri Bajaj, Robert Galamaga, John Eklund, James Wallace, Mikhail Shtivelband, Jason Jung-Gon Suh, Nafisa Burhani, Matthew Eadens, Krishna Gunturu, Earle Burgess, John Wong, Arvind Chaudhry, Peter Van Veldhuizen, Stephanie Graff, Christian A Thomas, Ian D Schnadig, Benedito Carneiro, Maha Hussain, Alicia Morgans, John T Fitzharris, Ira A Oliff, Jacqueline Vuky, Ralph Hauke, Ari Baron, Monika Joshi, Britt H Bolemon, Peter Jiang, Anthony E Mega, Maurice Markus, Nicklas Pfanzelter, William Eyre Lawler, Patrick Wayne Cobb, Jay G Courtright, Sharad Jain, Gurjyot Doshi, Vijay K Gunuganti, Oliver Alton Sartor, Scott W Cole, Hani Babiker, Edward M Uchio, Alexandra Drakaki, Heather D Mannuel, Elizabeth Guancial, Chunkit Fung, Anthony Charles, Robert J Amato, Yull Arriaga, Isaac Bowman, Steven Ades, Robert Dreicer, Evan Yu, David I Quinn, Mark Fleming, University of Zurich, Powles, Thomas, KEYNOTE-361 Investigators, UCL - SSS/IREC/MIRO - Pôle d'imagerie moléculaire, radiothérapie et oncologie, UCL - (SLuc) Centre du cancer, and UCL - (SLuc) Unité d'oncologie médicale
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Male ,medicine.medical_specialty ,Time Factors ,medicine.medical_treatment ,Population ,610 Medicine & health ,Pembrolizumab ,Antibodies, Monoclonal, Humanized ,Deoxycytidine ,Gastroenterology ,Carboplatin ,03 medical and health sciences ,chemistry.chemical_compound ,Antineoplastic Agents, Immunological ,0302 clinical medicine ,Internal medicine ,Antineoplastic Combined Chemotherapy Protocols ,Clinical endpoint ,medicine ,Humans ,030212 general & internal medicine ,Progression-free survival ,education ,Immune Checkpoint Inhibitors ,Aged ,Chemotherapy ,education.field_of_study ,business.industry ,Carcinoma ,Hazard ratio ,Middle Aged ,Gemcitabine ,Progression-Free Survival ,Urinary Bladder Neoplasms ,Oncology ,chemistry ,030220 oncology & carcinogenesis ,10032 Clinic for Oncology and Hematology ,Disease Progression ,Female ,2730 Oncology ,Human medicine ,Cisplatin ,Urothelium ,business ,medicine.drug - Abstract
Summary Background PD-1 and PD-L1 inhibitors are active in metastatic urothelial carcinoma, but positive randomised data supporting their use as a first-line treatment are lacking. In this study we assessed outcomes with first-line pembrolizumab alone or combined with chemotherapy versus chemotherapy for patients with previously untreated advanced urothelial carcinoma. Methods KEYNOTE-361 is a randomised, open-label, phase 3 trial of patients aged at least 18 years, with untreated, locally advanced, unresectable, or metastatic urothelial carcinoma, with an Eastern Cooperative Oncology Group performance status of up to 2. Eligible patients were enrolled from 201 medical centres in 21 countries and randomly allocated (1:1:1) via an interactive voice-web response system to intravenous pembrolizumab 200 mg every 3 weeks for a maximum of 35 cycles plus intravenous chemotherapy (gemcitabine [1000 mg/m2] on days 1 and 8 and investigator's choice of cisplatin [70 mg/m2] or carboplatin [area under the curve 5] on day 1 of every 3-week cycle) for a maximum of six cycles, pembrolizumab alone, or chemotherapy alone, stratified by choice of platinum therapy and PD-L1 combined positive score (CPS). Neither patients nor investigators were masked to the treatment assignment or CPS. At protocol-specified final analysis, sequential hypothesis testing began with superiority of pembrolizumab plus chemotherapy versus chemotherapy alone in the total population (all patients randomly allocated to a treatment) for the dual primary endpoints of progression-free survival (p value boundary 0·0019), assessed by masked, independent central review, and overall survival (p value boundary 0·0142), followed by non-inferiority and superiority of overall survival for pembrolizumab versus chemotherapy in the patient population with CPS of at least 10 and in the total population (also a primary endpoint). Safety was assessed in the as-treated population (all patients who received at least one dose of study treatment). This study is completed and is no longer enrolling patients, and is registered at ClinicalTrials.gov , number NCT02853305 . Findings Between Oct 19, 2016 and June 29, 2018, 1010 patients were enrolled and allocated to receive pembrolizumab plus chemotherapy (n=351), pembrolizumab monotherapy (n=307), or chemotherapy alone (n=352). Median follow-up was 31·7 months (IQR 27·7–36·0). Pembrolizumab plus chemotherapy versus chemotherapy did not significantly improve progression-free survival, with a median progression-free survival of 8·3 months (95% CI 7·5–8·5) in the pembrolizumab plus chemotherapy group versus 7·1 months (6·4–7·9) in the chemotherapy group (hazard ratio [HR] 0·78, 95% CI 0·65–0·93; p=0·0033), or overall survival, with a median overall survival of 17·0 months (14·5–19·5) in the pembrolizumab plus chemotherapy group versus 14·3 months (12·3–16·7) in the chemotherapy group (0·86, 0·72–1·02; p=0·0407). No further formal statistical hypothesis testing was done. In analyses of overall survival with pembrolizumab versus chemotherapy (now exploratory based on hierarchical statistical testing), overall survival was similar between these treatment groups, both in the total population (15·6 months [95% CI 12·1–17·9] with pembrolizumab vs 14·3 months [12·3–16·7] with chemotherapy; HR 0·92, 95% CI 0·77–1·11) and the population with CPS of at least 10 (16·1 months [13·6–19·9] with pembrolizumab vs 15·2 months [11·6–23·3] with chemotherapy; 1·01, 0·77–1·32). The most common grade 3 or 4 adverse event attributed to study treatment was anaemia with pembrolizumab plus chemotherapy (104 [30%] of 349 patients) or chemotherapy alone (112 [33%] of 342 patients), and diarrhoea, fatigue, and hyponatraemia (each affecting four [1%] of 302 patients) with pembrolizumab alone. Six (1%) of 1010 patients died due to an adverse event attributed to study treatment; two patients in each treatment group. One each occurred due to cardiac arrest and device-related sepsis in the pembrolizumab plus chemotherapy group, one each due to cardiac failure and malignant neoplasm progression in the pembrolizumab group, and one each due to myocardial infarction and ischaemic colitis in the chemotherapy group. Interpretation The addition of pembrolizumab to first-line platinum-based chemotherapy did not significantly improve efficacy and should not be widely adopted for treatment of advanced urothelial carcinoma. Funding Merck Sharp and Dohme, a subsidiary of Merck, Kenilworth, NJ, USA.
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- 2021
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12. Identification of Gamma-Butyrolactone in JUUL Liquids
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Caroline O. Cobb, Justin L. Poklis, Michelle R. Peace, and Alaina K. Holt
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Health, Toxicology and Mutagenesis ,Electronic Nicotine Delivery Systems ,Lung injury ,Toxicology ,01 natural sciences ,Gas Chromatography-Mass Spectrometry ,Analytical Chemistry ,Screening analysis ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,4-Butyrolactone ,Lc ms ms ,Humans ,Environmental Chemistry ,030212 general & internal medicine ,Drug enforcement ,Chemical Health and Safety ,gamma-Butyrolactone ,Chromatography ,Special Issue ,Chemistry ,Vaping ,010401 analytical chemistry ,United States ,0104 chemical sciences ,Gas chromatography–mass spectrometry ,Chromatography, Liquid - Abstract
Gamma-butyrolactone (GBL), a commonly used industrial solvent, is used recreationally as a central nervous system (CNS) depressant and, therefore, is a United States Drug Enforcement Agency List 1 chemical of the Controlled Substances Act. GBL was identified presumptively in the liquid from JUUL Virginia Tobacco flavored pods during routine untargeted screening analysis of e-cigarette products by gas chromatography–mass spectrometry (GC–MS). Methods for the analysis of GBL were developed for GC–MS and liquid chromatography–tandem mass spectrometry (LC–MS-MS) in the liquids and the aerosol generated from the liquid. Three flavors of JUUL pods available at the time of analysis were obtained by direct purchase from the manufacturer, purchase from a local vape shop and submission from a third party. The only liquid flavor to contain GBL was Virginia Tobacco, with an average of 0.37 mg/mL of GBL, and it was detected in the aerosol. Studies evaluating the pharmacological effects of inhaling GBL do not exist; however, a case report of chronic oral GBL ingestion indicates acute lung injury. The identification of GBL in an e-cigarette product purportedly compliant with federal regulation continues to demonstrate public health and public safety concerns.
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- 2021
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13. Fengycin A Analogues with Enhanced Chemical Stability and Antifungal Properties
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Cormac D. Murphy, Aoife Phelan, Diana Gimenez, and Steven L. Cobb
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Antifungal ,Letter ,Antifungal Agents ,Molecular Structure ,010405 organic chemistry ,medicine.drug_class ,Chemistry ,Organic Chemistry ,Total synthesis ,Bacillus ,Bacillus sp ,010402 general chemistry ,01 natural sciences ,Biochemistry ,Combinatorial chemistry ,Peptides, Cyclic ,0104 chemical sciences ,Lipopeptides ,medicine ,Chemical stability ,Physical and Theoretical Chemistry - Abstract
Fengycins are cyclic lipo-depsipeptides produced by Bacillus spp. that display potent antifungal properties but are chemically unstable. This instability has meant that no total synthesis of any fengycin has been published. Here we report the synthesis of fengycin A analogues that display enhanced antifungal properties and chemical stability under both basic and acidic conditions. The analogues prepared also demonstrate that the fengycin core structure can be modified and simplified without the loss of antifungal activity.
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- 2021
14. Seasonal Characterization of Bacterial Communities in Industrial Wastewater and Their Relationship with Flocculation Indices and Extracellular Polymeric Substances
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Gregory D. Martin, Birendra Dhungana, George P. Cobb, Marco E. Franco, Michael Abel, Ramon Lavado, Kamphy Patel, and Vanya Krahenbuhl
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Industrial wastewater treatment ,Flocculation ,Extracellular polymeric substance ,Chemistry (miscellaneous) ,Chemistry ,Environmental chemistry ,Environmental Chemistry ,Chemical Engineering (miscellaneous) ,Water Science and Technology - Published
- 2021
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15. Miniaturized probe on polymer SU-8 with array of individually addressable microelectrodes for electrochemical analysis in neural and other biological tissues
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Miguel Abrego Tello, Mengjia Hu, Mahsa Lotfi Marchoubeh, Samuel J. Cobb, Ingrid Fritsch, Julie V. Macpherson, Adrian C. Michael, Andrea Jaquins-Gerstl, and Elaine M. Robbins
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Microdialysis ,Materials science ,business.industry ,010401 analytical chemistry ,02 engineering and technology ,Electrolyte ,021001 nanoscience & nanotechnology ,Electrochemistry ,01 natural sciences ,Biochemistry ,0104 chemical sciences ,Analytical Chemistry ,Microelectrode ,Potassium ferricyanide ,chemistry.chemical_compound ,chemistry ,Electrode ,Optoelectronics ,Wafer ,0210 nano-technology ,business ,Microfabrication - Abstract
An SU-8 probe with an array of nine, individually addressable gold microband electrodes (100 μm long, 4 μm wide, separated by 4-μm gaps) was photolithographically fabricated and characterized for detection of low concentrations of chemicals in confined spaces and in vivo studies of biological tissues. The probe’s shank (6 mm long, 100 μm wide, 100 μm thick) is flexible, but exhibits sufficient sharpness and rigidity to be inserted into soft tissue. Laser micromachining was used to define probe geometry by spatially revealing the underlying sacrificial aluminum layer, which was then etched to free the probes from a silicon wafer. Perfusion with fluorescent nanobeads showed that, like a carbon fiber electrode, the probe produced no noticeable damage when inserted into rat brain, in contrast to damage from an inserted microdialysis probe. The individual addressability of the electrodes allows single and multiple electrode activation. Redox cycling is possible, where adjacent electrodes serve as generators (that oxidize or reduce molecules) and collectors (that do the opposite) to amplify signals of small concentrations without background subtraction. Information about electrochemical mechanisms and kinetics may also be obtained. Detection limits for potassium ferricyanide in potassium chloride electrolyte of 2.19, 1.25, and 2.08 μM and for dopamine in artificial cerebral spinal fluid of 1.94, 1.08, and 5.66 μM for generators alone and for generators and collectors during redox cycling, respectively, were obtained.
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- 2021
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16. Machine learning to determine optimal conditions for controlling the size of elastin-based particles
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Alexandra Engel, Jared S. Cobb, Amol V. Janorkar, and Maria Seale
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0301 basic medicine ,Phase transition ,Hydrodynamic radius ,Science ,Salt (chemistry) ,02 engineering and technology ,Lower critical solution temperature ,Article ,Phase Transition ,Biomaterials ,Machine Learning ,03 medical and health sciences ,Drug Delivery Systems ,Humans ,Transition Temperature ,chemistry.chemical_classification ,Multidisciplinary ,Aggregate (composite) ,Chemistry ,Gene Transfer Techniques ,Temperature ,Polymer ,021001 nanoscience & nanotechnology ,Polyelectrolyte ,Elastin ,Cold Temperature ,Hysteresis ,030104 developmental biology ,Chemical engineering ,Hydrodynamics ,Medicine ,Peptides ,0210 nano-technology ,Biomedical materials ,Hydrophobic and Hydrophilic Interactions ,Elementary Particles - Abstract
This paper evaluates the aggregation behavior of a potential drug and gene delivery system that combines branched polyethyleneimine (PEI), a positively-charged polyelectrolyte, and elastin-like polypeptide (ELP), a recombinant polymer that exhibits lower critical solution temperature (LCST). The LCST behavior of ELP has been extensively studied, but there are no quantitative ways to control the size of aggregates formed after the phase transition. The aggregate size cannot be maintained when the temperature is lowered below the LCST, unless the system exhibits hysteresis and forms irreversible aggregates. This study shows that conjugation of ELP with PEI preserves the aggregation behavior that occurs above the LCST and achieves precise aggregate radii when the solution conditions of pH (3, 7, 10), polymer concentration (0.1, 0.15, 0.3 mg/mL), and salt concentration (none, 0.2, 1 M) are carefully controlled. K-means cluster analyses showed that salt concentration was the most critical factor controlling the hydrodynamic radius and LCST. Conjugating ELP to PEI allowed crosslinking the aggregates and achieved stable particles that maintained their size below LCST, even after removal of the harsh (high salt or pH) conditions used to create them. Taken together, the ability to control aggregate sizes and use of crosslinking to maintain stability holds excellent potential for use in biological delivery systems.
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- 2021
17. 19F NMR as a tool in chemical biology
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Aoife Phelan, Steven L. Cobb, Diana Gimenez, and Cormac D. Murphy
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010405 organic chemistry ,Chemistry ,Organic Chemistry ,Chemical biology ,chemical biology ,Method of analysis ,Fluorine-19 NMR ,Review ,010402 general chemistry ,01 natural sciences ,0104 chemical sciences ,lcsh:QD241-441 ,Protein structure ,lcsh:Organic chemistry ,Computational chemistry ,fluorine ,Nucleic acid ,lcsh:Q ,biotransformation ,protein structure ,probes ,lcsh:Science ,19f nmr ,Macromolecule - Abstract
We previously reviewed the use of 19F NMR in the broad field of chemical biology [Cobb, S. L.; Murphy, C. D. J. Fluorine Chem. 2009, 130, 132–140] and present here a summary of the literature from the last decade that has the technique as the central method of analysis. The topics covered include the synthesis of new fluorinated probes and their incorporation into macromolecules, the application of 19F NMR to monitor protein–protein interactions, protein–ligand interactions, physiologically relevant ions and in the structural analysis of proteins and nucleic acids. The continued relevance of the technique to investigate biosynthesis and biodegradation of fluorinated organic compounds is also described.
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- 2021
18. Single‐Step Sulfur Insertions into Iron Carbide Carbonyl Clusters: Unlocking the Synthetic Door to FeMoco Analogues
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Chris Joseph, Michael J. Rose, and Caitlyn R. Cobb
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FeMoco ,010405 organic chemistry ,Chemistry ,chemistry.chemical_element ,Single step ,General Chemistry ,General Medicine ,010402 general chemistry ,Chloride ,01 natural sciences ,Sulfur ,Catalysis ,0104 chemical sciences ,Carbide ,chemistry.chemical_compound ,Crystallography ,Biomimetic synthesis ,Electrophile ,medicine ,Cluster (physics) ,medicine.drug - Abstract
We report the one-step syntheses, X-ray structures, and spectroscopic characterization of synthetic iron clusters bearing inorganic sulfides or thiolate with interstitial carbide motifs. Treatment of historical iron-carbide-carbonyl clusters [Fe n ( μ n -C)(CO) m ] x ( n = 5,6; m = 15,16; x = 0,-2) with electrophilic sulfur sources (S 2 Cl 2 , S 8 ) results in the formation of several μ 4 -S 'dimers of clusters' ( 1 and 2 ), and moreover the iron-sulfide-(sulfocarbide) clusters 3 and 4 . The core 'carbide' motif in 3 and 4 is the sulfocarbide unit {C-S} 4- , which serves as a structural model for the proposed intermediate in the radical-SAM biogenesis of the M-cluster. Furthermore, the 'electrophilic sulfur' strategy has been extended to provide the first ever thiolato-iron-carbide complex: An analogous reaction with toluylsulfenyl-chloride (tolS-Cl) affords the cluster [Fe 5 ( μ 5 -C)(SC 7 H 7 )(CO) 13 ] - ( 5 ). The 'electrophilic sulfur donor' strategy described herein provides a breakthrough towards developing logical syntheses of biomimetic iron-sulfur-carbide clusters like FeMoco.
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- 2020
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19. Bridged and Unbridged Nickel–Nickel Bonds Supported by Cyclopentadienyl and Phosphine Ligand Sets
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Ashley J. Wooles, Stephen T. Liddle, Lisa Vondung, Philip J. Cobb, Alexander J. Ayres, Peter A. Cleaves, and John C. Stewart
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010405 organic chemistry ,Ligand ,Chemistry ,Organic Chemistry ,chemistry.chemical_element ,010402 general chemistry ,01 natural sciences ,Medicinal chemistry ,0104 chemical sciences ,3. Good health ,Inorganic Chemistry ,chemistry.chemical_compound ,Nickel ,Cyclopentadienyl complex ,Physical and Theoretical Chemistry ,Phosphine - Abstract
A series of Ni complexes [Ni(Cl)2(PR3)2] with R = Me (1-Me), nPr (1-nPr), and nBu (1-nBu) and nickelocenes [Ni(η5-C5H4R′)2] with R′ = H (2-H), Me (2-Me), and SiMe3 (2-SiMe3) were synthesized and ch...
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- 2020
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20. Unusual Magnetic Field Responsive Circularly Polarized Luminescence Probes with Highly Emissive Chiral Europium(III) Complexes
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Junhui Zhang, Wesley Ting Kwok Chan, Alexandra M. Webster, Lewis Mackenzie, Ga Lai Law, Robert Pal, Steven L. Cobb, and Lixiong Dai
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Lanthanide ,lanthanide ,Field (physics) ,chirality ,chemistry.chemical_element ,Quantum yield ,010402 general chemistry ,Photochemistry ,01 natural sciences ,Catalysis ,QD ,Research Articles ,Luminescence Probes ,010405 organic chemistry ,circularly polarized luminescence ,General Chemistry ,General Medicine ,0104 chemical sciences ,Magnetic field ,Linear relationship ,chemistry ,magnetic properties ,Luminescence ,Europium ,Chirality (chemistry) ,Research Article - Abstract
Chirality is ubiquitous within biological systems where many of the roles and functions are still undetermined. Given this, there is a clear need to design and develop sensitive chiral optical probes that can function within a biological setting. Here we report the design and synthesis of magnetically responsive Circularly Polarized Luminescence (CPL) complexes displaying exceptional photophysical properties (quantum yield up to 31 % and |glum| up to 0.240) by introducing chiral substituents onto the macrocyclic scaffolds. Magnetic CPL responses are observed in these chiral EuIII complexes, promoting an exciting development to the field of magneto‐optics. The |glum| of the 5D0 → 7F1 transition increases by 20 % from 0.222 (0 T) to 0.266 (1.4 T) displaying a linear relationship between the Δglum and the magnetic field strength. These EuIII complexes with magnetic CPL responses, provides potential development to be used in CPL imaging applications due to improved sensitivity and resolution., A series of chiral, water‐soluble, DO3A‐based EuIII complexes was designed and synthesized. The chiral substituents introduced onto the macrocyclic scaffolds enhanced the photophysical properties with quantum yields up to 31 % and |glum| up to 0.240. The |glum| value increased by 20 % from 0.222 to 0.267 under external magnetic field showing a linear response.
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- 2020
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21. A quantitative meta-analysis of brain glutamate metabolites in aging
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J. Cobb Scott, Paul J. Moberg, Ravinder Reddy, Madison Woods, David R. Roalf, David A. Wolk, and Valerie J. Sydnor
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Male ,0301 basic medicine ,Aging ,medicine.medical_specialty ,Metabolite ,Biology ,Article ,03 medical and health sciences ,chemistry.chemical_compound ,Glutamatergic ,0302 clinical medicine ,Glutamates ,Internal medicine ,medicine ,Humans ,Neurotransmitter ,Aged ,Neurotransmitter Agents ,Spectrum Analysis ,General Neuroscience ,Glutamate receptor ,Brain ,Cognition ,Middle Aged ,Magnetic Resonance Imaging ,Phenotype ,Glutamine ,030104 developmental biology ,Endocrinology ,chemistry ,Cognitive Aging ,Meta-analysis ,Female ,Neurology (clinical) ,Geriatrics and Gerontology ,030217 neurology & neurosurgery ,Developmental Biology - Abstract
Glutamate (Glu) is a key molecule in cellular metabolism, the most abundant excitatory neurotransmitter in the brain, and the principal neurotransmitter of cortical efferents. Glutamate dysfunction, on the other hand, is common in neurodegenerative disorders, and likely contributes to age-related declines in behavioral and cognitive functioning. Nonetheless, the extant literature measuring age-related changes in brain glutamate in vivo has yet to be comprehensively and quantitatively summarized. This meta-analysis examines proton spectroscopy (1HMRS) measures of Glu-related brain metabolites across 589 healthy young and older adults. Glu (Cohen's d = −0.82) and Glu+glutamine (Cohen's d = −0.51) concentrations were significantly lower in older compared with younger adults, whereas the concentration of glutamine (d = 0.43) was significantly higher in older individuals. Notably, 1HMRS methodological choices impacted effect sizes for age-related Glu differences. Glu metabolite change appears to be a robust marker of aging-related neurological change; however, additional studies are needed to elucidate age-related trajectories of glutamatergic alterations and their relationship to cognitive phenotypes.
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- 2020
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22. Assessment of acid and thermal oxidation treatments for removing sp2 bonded carbon from the surface of boron doped diamond
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Georgia Wood, Fraser Laidlaw, Geoff West, Julie V. Macpherson, Mark E. Newton, Samuel J. Cobb, and Richard Beanland
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Thermal oxidation ,Materials science ,Electron energy loss spectroscopy ,Diamond ,chemistry.chemical_element ,02 engineering and technology ,General Chemistry ,Chemical vapor deposition ,engineering.material ,010402 general chemistry ,021001 nanoscience & nanotechnology ,01 natural sciences ,0104 chemical sciences ,Surface micromachining ,Amorphous carbon ,Chemical engineering ,chemistry ,engineering ,General Materials Science ,Graphite ,0210 nano-technology ,Carbon - Abstract
The presence of sp2 bonded carbon on a diamond or doped diamond surface, as a result of growth or processing, can affect material properties negatively, hence removal processes must be developed. Using boron doped diamond (BDD) we investigate the effectiveness of different removal methods via electrochemistry and transmission electron microscopy. We focus on two BDD surfaces, one processed by ns laser micromachining and the second which contains sp2 bonded carbon as a result of chemical vapour deposition (CVD) growth. After micromachining a layer of ordered graphite sits on the BDD surface, topped by fissured amorphous carbon (total thickness ∼ μm). Oxidative acid treatment at elevated temperature cannot remove all the sp2 bonded carbon and much smaller clusters of perpendicularly-orientated graphite (tens of nm in diameter), capped with a thinner layer of amorphous carbon – that we term “denatured graphite” – remain. In contrast, thermal oxidation in air at 600 °C is capable of all cluster removal, and can also be used to remove sp2 bonded carbon from as-grown CVD BDD. Such understanding is important to any application where sp2 bonded surface carbon resulting from CVD growth or laser processing is detrimental for the intended application, e.g. in diamond quantum technology, photonics and electrochemistry.
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- 2020
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23. Autoclaving of Poloxamer 407 hydrogel and its use as a drug delivery vehicle
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Lauren B. Priddy, Taylor Henry, Santanu Kundu, Mary Catherine Beard, Anandavalli Varadarajan, Elizabeth A. Swanson, Christine S. Grant, and Leah H. Cobb
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Staphylococcus aureus ,Hot Temperature ,Materials science ,Biomedical Engineering ,Poloxamer ,02 engineering and technology ,complex mixtures ,Article ,Autoclave ,Biomaterials ,03 medical and health sciences ,Vancomycin ,In vivo ,medicine ,030304 developmental biology ,chemistry.chemical_classification ,Drug Carriers ,0303 health sciences ,technology, industry, and agriculture ,Biomaterial ,Hydrogels ,Polymer ,Sterilization (microbiology) ,021001 nanoscience & nanotechnology ,chemistry ,Poloxamer 407 ,Drug delivery ,Self-healing hydrogels ,0210 nano-technology ,Biomedical engineering ,medicine.drug - Abstract
With antibiotic-resistant bacteria becoming increasingly prevalent, biomaterials capable of targeted, in situ drug delivery are urgently needed. The synthetic polymer Poloxamer 407 (P407) is of particular interest due to its thermoreversible gelation. Clinical use of P407 typically involves sterilization via autoclaving, but the effects of these extreme environmental conditions on hydrogel water content, rheological properties and efficacy as a drug delivery vehicle remain unknown. The aim of this study was to investigate the effects of autoclaving on the properties of P407 hydrogel. Autoclaving reduced hydrogel water content due to evaporation, thus increasing the polymer weight fraction of the hydrogels. In contrast, except for a reduction in gelation temperature following autoclaving, autoclaved hydrogels had similar rheological properties as nonautoclaved hydrogels. In vitro, autoclaving did not hinder the hydrogel’s efficacy as a carrier for vancomycin antibiotic, and P407 (with and without vancomycin) had a bactericidal effect on planktonic Staphylococcus aureus. An in vivo pilot study using P407 to deliver bacteriophage highlighted the need for additional understanding of the functionality of the hydrogel for surgical applications. In conclusion, P407 hydrogel water content and gelation temperature were reduced by autoclave sterilization, while other rheological properties and the efficacy of the biomaterial as a delivery vehicle for vancomycin in vitro were unaffected.
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- 2020
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24. Nanoscale mechanisms in age-related hip-fractures
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John H. Churchwell, Richard L. Abel, En Lin Goh, Shaocheng Ma, Oliver Boughton, Ulrich Hansen, Angelo Karunaratne, Yong Wu, Tabitha Tay, Justin Cobb, Rajarshi Bhattacharya, Crispin C. Wiles, Nicholas J. Terrill, and National Osteoporosis Society
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0301 basic medicine ,Male ,Aging ,Fibrillar Collagens ,lcsh:Medicine ,Diseases ,Fibril ,Biochemistry ,Trauma ,Article ,Bone and Bones ,03 medical and health sciences ,0302 clinical medicine ,Age related ,Humans ,Tissue mechanics ,lcsh:Science ,Aged ,Aged, 80 and over ,Multidisciplinary ,Strain (chemistry) ,Chemistry ,Hip Fractures ,lcsh:R ,Nanostructures ,030104 developmental biology ,Cross-Sectional Studies ,Ageing ,Case-Control Studies ,Fracture (geology) ,Ultimate stress ,Osteoporosis ,Female ,lcsh:Q ,Tissue strain ,Structural biology ,030217 neurology & neurosurgery ,Biomedical engineering - Abstract
Nanoscale mineralized collagen fibrils may be important determinants of whole-bone mechanical properties and contribute to the risk of age-related fractures. In a cross-sectional study nano- and tissue-level mechanics were compared across trabecular sections from the proximal femora of three groups (n = 10 each): ageing non-fractured donors (Controls); untreated fracture patients (Fx-Untreated); bisphosphonate-treated fracture patients (Fx-BisTreated). Collagen fibril, mineral and tissue mechanics were measured using synchrotron X-Ray diffraction of bone sections under load. Mechanical data were compared across groups, and tissue-level data were regressed against nano. Compared to controls fracture patients exhibited significantly lower critical tissue strain, max strain and normalized strength, with lower peak fibril and mineral strain. Bisphosphonate-treated exhibited the lowest properties. In all three groups, peak mineral strain coincided with maximum tissue strength (i.e. ultimate stress), whilst peak fibril strain occurred afterwards (i.e. higher tissue strain). Tissue strain and strength were positively and strongly correlated with peak fibril and mineral strains. Age-related fractures were associated with lower peak fibril and mineral strain irrespective of treatment. Indicating earlier mineral disengagement and the subsequent onset of fibril sliding is one of the key mechanisms leading to fracture. Treatments for fragility should target collagen-mineral interactions to restore nano-scale strain to that of healthy bone.
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- 2020
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25. Genome-wide DNA methylation differences and polychlorinated biphenyl (PCB) exposure in a US population
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Alicia K. Smith, Karen N. Conneely, Metrecia L. Terrell, Sarah W. Curtis, Carmen J. Marsit, Dana B. Barr, Varun Kilaru, M. Elizabeth Marder, Dawayland O. Cobb, and Michele Marcus
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0301 basic medicine ,Cancer Research ,Polybrominated Biphenyls ,Population ,Endocrine Disruptors ,Biology ,Genome ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,Endocrine disrupting compound ,Humans ,Epigenetics ,education ,Molecular Biology ,Genetics ,education.field_of_study ,food and beverages ,Polychlorinated biphenyl ,DNA Methylation ,Polychlorinated Biphenyls ,030104 developmental biology ,Pcb exposure ,Diabetes Mellitus, Type 2 ,chemistry ,030220 oncology & carcinogenesis ,DNA methylation ,Research Paper - Abstract
Exposure to polychlorinated biphenyls (PCBs), an endocrine-disrupting compound, is ubiquitous despite decades-old bans on the manufacture and use of PCBs. Increased exposure to PCBs is associated with adverse health consequences throughout life, including type 2 diabetes and cancer. PCB exposure is also associated with alterations in epigenetic marks and gene transcription, which could lead to adverse health outcomes, but many of these are population-specific. To further investigate the association between PCB and epigenetic marks, DNA methylation was measured at 787,684 CpG sites in 641 peripheral blood samples from the Michigan Polybrominated Biphenyl (PBB) Registry. 1345 CpGs were associated with increased total PCB level after controlling for age, sex, and 24 surrogate variables (FDR < 0.05). These CpGs were enriched in active promoter and transcription associated regions (p
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- 2020
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26. Alcohol use severity, depressive symptoms, and optimism among Hispanics: Examining the immigrant paradox in a serial mediation model
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Seth J. Schwartz, Priscilla Martinez, Cory L. Cobb, Elma I. Lorenzo-Blanco, Charles R. Martinez, Alan Meca, Alejandra Garcia Isaza, Flavio F. Marsiglia, Miguel Ángel Cano, Christopher P. Salas-Wright, Miguel Pinedo, and Heather H. McClure
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Male ,050103 clinical psychology ,Alcohol Drinking ,media_common.quotation_subject ,Immigration ,Emigrants and Immigrants ,Alcohol ,macromolecular substances ,Models, Psychological ,Severity of Illness Index ,Immigrant paradox ,Article ,Young Adult ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,Optimism ,Arts and Humanities (miscellaneous) ,Humans ,0501 psychology and cognitive sciences ,Young adult ,Depression (differential diagnoses) ,Depressive symptoms ,media_common ,Depression ,05 social sciences ,Hispanic or Latino ,United States ,030227 psychiatry ,Clinical Psychology ,chemistry ,Female ,Psychology ,Clinical psychology ,Serial mediation - Abstract
Objective Hispanic immigrants exhibit more positive outcomes than U.S.-born Hispanics across educational, psychological, and physical health indices, a phenomenon called the immigrant paradox. We examined the immigrant paradox in relation to alcohol use severity among Hispanic young adults while considering both positive (optimism) and negative (depressive symptoms) processes. Method Among 200 immigrant and U.S.-born Hispanic young adults (Mage = 21.30; 49% male) in Arizona and Florida, we tested whether optimism and depressive symptoms statistically mediated the relationship between nativity and alcohol use severity. Specifically, we examined whether Hispanic immigrants reported greater optimism than their U.S.-born counterparts, and whether such optimism was, in turn, associated with less depressive symptoms and thus lower alcohol use severity. Results Indirect effects were significant in hypothesized directions (nativity → optimism → depressive symptoms → alcohol use severity). Conclusions Both positive and negative psychological processes are important to consider when accounting for the immigrant paradox vis-a-vis alcohol use severity among Hispanic young adults.
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- 2020
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27. Protecting Group-Controlled Remote Regioselective Electrophilic Aromatic Halogenation Reactions
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Steven L. Cobb and William D. G. Brittain
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010405 organic chemistry ,Organic Chemistry ,Halogenation ,Regioselectivity ,Electrophilic aromatic substitution ,010402 general chemistry ,01 natural sciences ,Combinatorial chemistry ,0104 chemical sciences ,Organic molecules ,chemistry.chemical_compound ,chemistry ,Electrophile ,Phenol ,Protecting group - Abstract
Being able to utilise a protecting group to influence remote regiocontrol offers a simple alternative approach to direct late-stage functionalisation of complex organic molecules. However, protecting groups that have the ability to influence reaction regioselectivity remote to their local chemical environment are not widely reported in the literature. Herein, we report the development of remote regioselective electrophilic aromatic substitution (SEAr) reactions that are enabled via the application of the tetrafluoropyridyl (TFP) phenol protecting group. We demonstrate that through sequential reactions and protection/deprotection of the TFP group, substitution patterns which do not conform to classical SEAr regioselectivity rules can be readily accessed.
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- 2020
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28. Variation in mobility and exercise adaptations between Drosophila species
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Robert Wessells, Courtney Morton, Alyson Sujkowski, Tyler Cobb, and Divya Ramesh
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Male ,Adult male ,Physiology ,Zoology ,Tyramine ,Intraspecific competition ,03 medical and health sciences ,Behavioral Neuroscience ,chemistry.chemical_compound ,0302 clinical medicine ,Species Specificity ,ddc:570 ,Physical Conditioning, Animal ,Melanogaster ,Animals ,Drosophila ,Exercise ,Octopamine ,Ecology, Evolution, Behavior and Systematics ,030304 developmental biology ,Mobility ,Neurons ,0303 health sciences ,Original Paper ,biology ,Adrenergic Uptake Inhibitors ,Octopamine (drug) ,Interspecific competition ,biology.organism_classification ,Adaptation, Physiological ,chemistry ,Climbing ,Animal Science and Zoology ,Female ,Drosophila melanogaster ,Adrenergic alpha-Agonists ,030217 neurology & neurosurgery ,Locomotion - Abstract
Locomotion and mobility have been studied extensively in Drosophila melanogaster but less is known about the locomotor capacity of other Drosophila species, while the response to chronic exercise in other species has yet to be examined. We have shown that adult male D. melanogaster adapt to exercise training with improved running endurance, climbing speed, and flight ability compared to unexercised flies. Here, we examine baseline mobility of D. sechellia, D. simulans, and D. virilis, and their response to chronic exercise training. We found significant interspecific differences in mobility and in the response to exercise. Although there is a significant sex difference in exercise adaptations in D. melanogaster, intraspecific analysis reveals few sex differences in other Drosophila species. As octopamine has been shown to be important for exercise adaptations in D. melanogaster, we also asked if any observed differences could be attributed to baseline octopamine levels. We find that octopamine and tyramine levels have the same rank order as baseline climbing speed and endurance in males, but do not predict the response to chronic exercise in males or females. Future research should focus on determining the mechanisms responsible for the inter- and intraspecific differences in mobility and the response to exercise.
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- 2020
29. No consistent ENSO response to volcanic forcing over the last millennium
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Sylvia G. Dee, Christopher D. Charles, Kim M. Cobb, Toby R. Ault, Julien Emile-Geay, Hai Cheng, and R. Lawrence Edwards
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Tropical pacific ,geography ,Multidisciplinary ,geography.geographical_feature_category ,Superposed epoch analysis ,Forcing (mathematics) ,Volcanism ,Radiative forcing ,chemistry.chemical_compound ,El Niño Southern Oscillation ,Volcano ,chemistry ,Climatology ,Sulfate aerosol ,Geology - Abstract
Not a big deal after all Do volcanic eruptions affect El Niño–Southern Oscillation (ENSO) variability? Models indicate that sulfate aerosols resulting from large eruptions can initiate an El Niño–like response in the tropical Pacific, but observations have not shown evidence of such behavior. Dee et al . present an oxygen-isotope time series of fossil corals from the central tropical Pacific to investigate ENSO's response to large volcanic eruptions during the past millennium. They found a weak tendency for an El Niño–like response in the year after an eruption, but not one that was statistically significant. These results suggest that large volcanic events have not triggered a detectable response in ENSO over the past thousand years and that their impact is small relative to the degree of natural variability. Science , this issue p. 1477
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- 2020
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30. The glutamic acid-rich–long C-terminal extension of troponin T has a critical role in insect muscle functions
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Tyler Cobb, Jian Ping Jin, Tianxin Cao, Alyson Sujkowski, and Robert Wessells
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Male ,0301 basic medicine ,Myofilament ,X Chromosome ,Glutamic Acid ,Tropomyosin ,Biochemistry ,Sarcomere ,Troponin C ,03 medical and health sciences ,Myofibrils ,Protein Domains ,Troponin T ,Troponin complex ,Troponin I ,medicine ,Animals ,Drosophila Proteins ,Muscle, Skeletal ,Molecular Biology ,Phylogeny ,030102 biochemistry & molecular biology ,Chemistry ,fungi ,Cell Biology ,Striated muscle contraction ,musculoskeletal system ,Recombinant Proteins ,Cell biology ,Alternative Splicing ,030104 developmental biology ,Protein Synthesis and Degradation ,Mutagenesis ,Flight, Animal ,Calcium ,Drosophila ,Female ,medicine.symptom ,CD27 Ligand ,Muscle Contraction ,Muscle contraction - Abstract
The troponin complex regulates the Ca(2+) activation of myofilaments during striated muscle contraction and relaxation. Troponin genes emerged 500–700 million years ago during early animal evolution. Troponin T (TnT) is the thin-filament–anchoring subunit of troponin. Vertebrate and invertebrate TnTs have conserved core structures, reflecting conserved functions in regulating muscle contraction, and they also contain significantly diverged structures, reflecting muscle type- and species-specific adaptations. TnT in insects contains a highly-diverged structure consisting of a long glutamic acid–rich C-terminal extension of ∼70 residues with unknown function. We found here that C-terminally truncated Drosophila TnT (TpnT–CD70) retains binding of tropomyosin, troponin I, and troponin C, indicating a preserved core structure of TnT. However, the mutant TpnT(CD70) gene residing on the X chromosome resulted in lethality in male flies. We demonstrate that this X-linked mutation produces dominant-negative phenotypes, including decreased flying and climbing abilities, in heterozygous female flies. Immunoblot quantification with a TpnT-specific mAb indicated expression of TpnT–CD70 in vivo and normal stoichiometry of total TnT in myofilaments of heterozygous female flies. Light and EM examinations revealed primarily normal sarcomere structures in female heterozygous animals, whereas Z-band streaming could be observed in the jump muscle of these flies. Although TpnT–CD70-expressing flies exhibited lower resistance to cardiac stress, their hearts were significantly more tolerant to Ca(2+) overloading induced by high-frequency electrical pacing. Our findings suggest that the Glu-rich long C-terminal extension of insect TnT functions as a myofilament Ca(2+) buffer/reservoir and is potentially critical to the high-frequency asynchronous contraction of flight muscles.
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- 2020
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31. Understanding the Local Chemical Environment of Bioelectrocatalysis
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Inês A. C. Pereira, Esther Edwardes Moore, Erwin Reisner, Ana Margarida Coito, Ana Rita Oliveira, Samuel J. Cobb, Cobb, Samuel [0000-0001-5015-8090], Reisner, Erwin [0000-0002-7781-1616], and Apollo - University of Cambridge Repository
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Work (thermodynamics) ,Materials science ,Hydrogen ,enzymes ,sex determination ,chemistry.chemical_element ,local pH ,02 engineering and technology ,Electrolyte ,Buffers ,010402 general chemistry ,Electrochemistry ,01 natural sciences ,Redox ,Electrolytes ,Structure-Activity Relationship ,Malawi African cichlids ,Electrodes ,Multidisciplinary ,Molecular Structure ,bioelectrochemistry ,sex chromosomes ,Electrochemical Techniques ,021001 nanoscience & nanotechnology ,0104 chemical sciences ,hydrogen evolution ,Chemistry ,Chemical engineering ,Porous electrode ,chemistry ,CO2 reduction ,sexual dimorphism ,Physical Sciences ,Electrode ,Local environment ,0210 nano-technology ,Microelectrodes ,Porosity ,Algorithms - Abstract
Significance Enzyme bioelectrochemistry concerns the integration of oxidoreductase enzymes into electrodes to enable and study the transfer of electrons between the solid-state material surface and the biological catalyst. To achieve higher enzyme loading, and hence greater current densities, high-surface-area strategies have been employed to immobilize enzymes, but these porous electrode architectures amplify the formation of local chemical gradients. Enzyme selectivity and activity is highly dependent on such changes in local environment, such as substrate concentration, pH, and electrolyte species concentration. Here, electrochemistry and computational techniques are applied to explore, and hence optimize, the local environment of the fuel-producing oxidoreductases, hydrogenase and formate dehydrogenase, within porous electrodes., Bioelectrochemistry employs an array of high-surface-area meso- and macroporous electrode architectures to increase protein loading and the electrochemical current response. While the local chemical environment has been studied in small-molecule and heterogenous electrocatalysis, conditions in enzyme electrochemistry are still commonly established based on bulk solution assays, without appropriate consideration of the nonequilibrium conditions of the confined electrode space. Here, we apply electrochemical and computational techniques to explore the local environment of fuel-producing oxidoreductases within porous electrode architectures. This improved understanding of the local environment enabled simple manipulation of the electrolyte solution by adjusting the bulk pH and buffer pKa to achieve an optimum local pH for maximal activity of the immobilized enzyme. When applied to macroporous inverse opal electrodes, the benefits of higher loading and increased mass transport were employed, and, consequently, the electrolyte adjusted to reach −8.0 mA ⋅ cm−2 for the H2 evolution reaction and −3.6 mA ⋅ cm−2 for the CO2 reduction reaction (CO2RR), demonstrating an 18-fold improvement on previously reported enzymatic CO2RR systems. This research emphasizes the critical importance of understanding the confined enzymatic chemical environment, thus expanding the known capabilities of enzyme bioelectrocatalysis. These considerations and insights can be directly applied to both bio(photo)electrochemical fuel and chemical synthesis, as well as enzymatic fuel cells, to significantly improve the fundamental understanding of the enzyme–electrode interface as well as device performance.
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- 2021
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32. Effect of an electronic nicotine delivery system with 0, 8, or 36 mg/mL liquid nicotine versus a cigarette substitute on tobacco-related toxicant exposure: a four-arm, parallel-group, randomised, controlled trial
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Caroline O Cobb, Jonathan Foulds, Miao-Shan Yen, Susan Veldheer, Alexa A Lopez, Jessica M Yingst, Christopher Bullen, Le Kang, Thomas Eissenberg, Sophia I. Allen, Phoebe Brosnan, Nadia Chowdhury, Caroline O. Cobb, Jacob T. Graham, Erin Hammett, Sharilee Hrabovsky, Breianna L. Hummer, Courtney Lester, Alexa A. Lopez, John P. Richie, Christopher Sciamanna, Shumei Sun, Thokozeni Lipato, and Jessica M. Yingst
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Pulmonary and Respiratory Medicine ,medicine.medical_specialty ,Urinary system ,Electronic Nicotine Delivery Systems ,Article ,law.invention ,Nicotine ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,Randomized controlled trial ,law ,Internal medicine ,Medicine ,Humans ,030212 general & internal medicine ,Adverse effect ,Smoking Reduction ,Creatinine ,business.industry ,Smoking ,030228 respiratory system ,chemistry ,Nicotine delivery ,Smoking Cessation ,Public Health ,business ,Toxicant ,medicine.drug - Abstract
Summary Background Electronic nicotine delivery systems (ENDSs) are used by some smokers to reduce cigarette consumption, but their effectiveness is uncertain. We aimed to examine the extent to which ENDSs or a non-nicotine cigarette substitute influence tobacco-related toxicant exposure and cigarette consumption in smokers interested in smoking reduction. Methods We did a four-arm, parallel-group, randomised controlled trial at two sites in the USA (Penn State University, Hershey, PA, and Virginia Commonwealth University, Richmond, VA). We enrolled adults aged 21–65 years who smoked more than nine cigarettes per day (for at least the past year), with exhaled CO of more than 9 parts per million at screening, who were not currently using an ENDS, and who were interested in reducing smoking but not quitting. Participants were randomised (site-specific with allocation concealment; 1:1:1:1) to receive either a cartomiser-based, pen-style ENDS (eGo-style) paired with 0, 8, or 36 mg/mL liquid nicotine (participants and researchers masked to concentration) or a non-ENDS cigarette-shaped plastic tube that delivered no nicotine or aerosol (cigarette substitute; unmasked) for 24 weeks. Conditions were chosen to reflect a range of nicotine delivery including none (cigarette substitute and 0 mg/mL ENDS), low (8 mg/mL), and cigarette-like (36 mg/mL), and all conditions were paired with smoking reduction instructions. The primary outcome was concentration of the tobacco-specific carcinogen metabolite 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol (NNAL; urinary total) collected at randomisation and at 4, 12, and 24 weeks. Multiple imputation with and without covariate adjustment was used in addition to sensitivity analyses. This trial is registered with ClinicalTrials.gov, NCT02342795. Findings Between July 22, 2015, and Nov 16, 2017, 684 individuals were screened and 520 (76%) were enrolled and randomised. 188 (36%) of 520 participants were lost to follow-up by week 24; attrition did not differ by study group (39 [30%] of 130 in the cigarette substitute group, 56 [43%] of 130 in the ENDS with 0 mg/mL nicotine group, 49 [38%] of 130 in the ENDS 8 mg/mL group, and 44 [34%] of 130 in the ENDS 36 mg/mL group). Urinary total NNAL at 24 weeks in the ENDS with 36 mg/mL nicotine group was 210·80 pg/mg creatinine (95% CI 163·03–274·42) compared with 346·09 pg/mg creatinine (265·00–455·32) in the cigarette substitute group (p=0·0061). No other significant differences between groups were observed for any time point for urinary total NNAL. Serious adverse event frequency was similar across groups (12 events in 12 participants [9%] in the ENDS with 36 mg/mL nicotine group, seven events in six participants [5%] in the 8 mg/mL group, 11 events in ten participants [8%] in the 0 mg/mL group, and 13 events in 13 participants [10%] in the cigarette substitute group), and all of these were deemed unrelated or unlikely to be related to study product use. There was one death between randomisation and 24 weeks (suicide; in the ENDS with 0 mg/mL nicotine group). Interpretation Use of an ENDS with cigarette-like nicotine delivery can reduce exposure to a major pulmonary carcinogen, NNAL, even with concurrent smoking. Future ENDS trials should involve products with well characterised nicotine delivery, including those with nicotine delivery approaching that of a cigarette. Funding National Institutes of Health, US Food and Drug Administration.
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- 2021
33. Diamond membrane production : the critical role of radicals in the non-contact electrochemical etching of sp2 carbon
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Matthew Markham, Emily Braxton, Joshua J. Tully, Julie V. Macpherson, Samuel J. Cobb, Paramaconi Rodriguez, Ben Breeze, and Mark E. Newton
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TP ,Materials science ,technology, industry, and agriculture ,chemistry.chemical_element ,Diamond ,General Chemistry ,Electrolyte ,engineering.material ,Electrochemistry ,Ion implantation ,Membrane ,chemistry ,Chemical engineering ,Etching (microfabrication) ,engineering ,General Materials Science ,Carbon ,Electrode potential - Abstract
Sub-micrometre single crystal diamond membranes are of huge importance for next generation optical, quantum and electronic device applications. Electrochemical etching has proven a critical step in the production of such membranes. Etching is used to selectively remove a very thin layer of sub-surface sp2 carbon, prepared by ion implantation in bulk diamond, releasing the diamond membrane. Due to the nanosized dimensions, etching is typically carried out using non-contact electrochemistry in low conductivity solutions (bipolar arrangement) which whilst effective, results in extremely slow etch rates. In this work, a new method of non-contact electrochemical etching is presented which uses high conductivity, high concentration, fully dissociated aqueous electrolytes. Careful choice of the electrolyte anion results in significant improvements in the sp2 carbon etch rate. In particular, we show both chloride and sulfate electrolytes increase etch rates significantly (up to × 40 for sulfate) compared to our measurements using the current state-of-the-art solutions and methodologies. Electron paramagnetic resonance experiments, recorded after the electrode potential has been switched off, reveal sizeable hydroxyl radical concentrations at timescales > 107 longer than their lifetime (≤μs). These measurements highlight the importance of electrochemically initiated, solution chemistry radical generation and regeneration pathways in high concentration sulfate and chloride solutions for nano-etching applications.
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- 2021
34. Cholesterol Regulates the Tumor Adaptive Resistance to MAPK Pathway Inhibition
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Smita Rindhe, Yonghao Yu, Yajie Zhang, Melanie H. Cobb, Chiho Kim, and Xu-Dong Wang
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MAPK/ERK pathway ,Proto-Oncogene Proteins B-raf ,Lung Neoplasms ,MAP Kinase Signaling System ,Biochemistry ,Article ,chemistry.chemical_compound ,In vivo ,Carcinoma, Non-Small-Cell Lung ,Cell Line, Tumor ,medicine ,Cytotoxic T cell ,Humans ,Tyrosine ,Melanoma ,Protein Kinase Inhibitors ,Kinase ,Cholesterol ,General Chemistry ,medicine.disease ,In vitro ,chemistry ,Mutation ,Cancer research - Abstract
Although targeted MAPK pathway inhibition has achieved remarkable patient responses in many cancers, the development of resistance has remained a critical challenge. Adaptive tumor response underlies the drug resistance. Furthermore, such bypass mechanisms often lead to the activation of many pro-survival kinases, which complicates the rational design of combination therapies. Here we performed global tyrosine phosphoproteomic (pTyr) analyses and demonstrated that targeted MAPK signaling inhibition in melanoma leads to a profound remodeling of the pTyr proteome. Intriguingly, altered cholesterol metabolism might drive, in a coordinated fashion, the activation of these kinases. Indeed, we found an accumulation of intracellular cholesterol in melanoma cells (with BRAF(V600E) mutations) and non-small cell lung cancer cells (with KRAS(G12C) mutations) treated with MAPK and KRAS(G12C) inhibitors, respectively. Importantly, depletion of cholesterol not only prevents the feedback activation of pTyr signaling but also enhances the cytotoxic effects of MAPK pathway inhibitors, both in vitro and in vivo. Together, our findings suggest that cholesterol contributes to the tumor adaptive response upon targeted MAPK pathway inhibitors. These results also suggest that MAPK pathway inhibitors could be combined with cholesterol-lowering agents to achieve a more complete and durable response in tumors with hyperactive MAPK signaling. PRIDE identifier: PXD021877.
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- 2021
35. Extracellular vesicles released by human retinal pigment epithelium mediate increased polarised secretion of drusen proteins in response to AMD stressors
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Jason Mighty, Patrick S. McGrath, Cui Shi, Michael J. Rudy, Patricia Lenhart, Stephen Redenti, Ganna Bilousova, Søren Heissel, S. Patricia Becerra, Miguel Flores-Bellver, Germán Michelis, Andrew Goodspeed, M. Valeria Canto-Soler, Hannah Cobb, Kang V. Li, Christina M. Coughlan, Silvia Aparicio-Domingo, and Jing Zhou
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Nicotine ,Histology ,genetic structures ,Induced Pluripotent Stem Cells ,Inflammation ,Retinal Drusen ,exosomes ,Retinal Pigment Epithelium ,Drusen ,AMD ,Extracellular Vesicles ,Macular Degeneration ,proteomics ,Phagocytosis ,stem cells ,medicine ,Humans ,Secretion ,Research Articles ,Cells, Cultured ,Secretome ,Retinal pigment epithelium ,QH573-671 ,Chemistry ,drusen ,Cell Polarity ,Proteins ,Cell Biology ,Macular degeneration ,medicine.disease ,Microvesicles ,eye diseases ,Cell biology ,Organoids ,Oxidative Stress ,medicine.anatomical_structure ,sense organs ,RPE ,medicine.symptom ,Cytology ,Reactive Oxygen Species ,microvesicles ,Homeostasis ,Biogenesis ,Research Article ,Signal Transduction - Abstract
Age‐related macular degeneration (AMD) is a leading cause of blindness worldwide. Drusen are key contributors to the etiology of AMD and the ability to modulate drusen biogenesis could lead to therapeutic strategies to slow or halt AMD progression. The mechanisms underlying drusen biogenesis, however, remain mostly unknown. Here we demonstrate that under homeostatic conditions extracellular vesicles (EVs) secreted by retinal pigment epithelium (RPE) cells are enriched in proteins associated with mechanisms involved in AMD pathophysiology, including oxidative stress, immune response, inflammation, complement system and drusen composition. Furthermore, we provide first evidence that drusen‐associated proteins are released as cargo of extracellular vesicles secreted by RPE cells in a polarised apical:basal mode. Notably, drusen‐associated proteins exhibited distinctive directional secretion modes in homeostatic conditions and, differential modulation of this directional secretion in response to AMD stressors. These observations underpin the existence of a finely‐tuned mechanism regulating directional apical:basal sorting and secretion of drusen‐associated proteins via EVs, and its modulation in response to mechanisms involved in AMD pathophysiology. Collectively, our results strongly support an active role of RPE‐derived EVs as a key source of drusen proteins and important contributors to drusen development and growth.
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- 2021
36. Efficacy of Chemical and Biological Stump Treatments for the Control of Heterobasidion occidentale Infection of California Abies concolor
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Christopher A. Lee, Adrian L. Poloni, Richard Cobb, and Matteo Garbelotto
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Microbiology (medical) ,Heterobasidion root disease ,Phlebiopsis gigantea ,white fir ,bark beetle ,California ,Bark beetle ,food.ingredient ,chemistry.chemical_compound ,food ,Immunology and Allergy ,Colonization ,Molecular Biology ,General Immunology and Microbiology ,biology ,Inoculation ,Abies concolor ,Heterobasidion occidentale ,Gigantea ,biology.organism_classification ,Horticulture ,Infectious Diseases ,chemistry ,Urea ,Medicine ,Heterobasidion - Abstract
We conducted an experimental evaluation of treatments to limit Heterobasidion occidentale infection of white fir (Abies concolor) stumps and wounds in California mixed conifer forests. We tested the efficacy of urea, borate, and a mixture of two locally collected Phlebiopsis gigantea strains in preventing pathogen colonization of fir stumps and separately, urea and borate as infection controls on experimental stem wounds. These were paired with a laboratory test on ~100 g wood blocks with and without a one-week delay between inoculation and treatment. Urea, borates, and Phlebiopsis treatments all significantly reduced the stump surface area that was colonized by H. occidentale at 84%, 91%, and 68%, respectively, relative to the controls. However, only the borate treatments significantly lowered the number of stumps that were infected by the pathogen. The laboratory study matched the patterns that were found in the stump experiment with a reduced area of colonization for urea, borates, or P. gigantea treatments relative to the controls; delaying the treatment did not affect efficacy. The field wound experiment did not result in any Heterobasidion colonization, even in positive control treatments, rendering the experiment uninformative. Our study suggests treatments that are known to limit Heterobasidion establishment on pine or spruce stumps elsewhere in the world may also be effective on true firs in California.
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- 2021
37. Kidney Disease, Hypertension Treatment, and Cerebral Perfusion and Structure
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Manjula Kurella Tamura, Sarah Gaussoin, Nicholas M. Pajewski, Greg Zaharchuk, Barry I. Freedman, Stephen R. Rapp, Alexander P. Auchus, William E. Haley, Suzanne Oparil, Jessica Kendrick, Christianne L. Roumie, Srinivasan Beddhu, Alfred K. Cheung, Jeff D. Williamson, John A. Detre, Sudipto Dolui, R. Nick Bryan, Ilya M. Nasrallah, Paul Whelton, Karen C. Johnson, Joni Snyder, Diane Bild, Denise Bonds, Nakela Cook, Jeffrey Cutler, Lawrence Fine, Peter Kaufmann, Paul Kimmel, Lenore Launer, Claudia Moy, William Riley, Laurie Ryan, Eser Tolunay, Song Yang, David Reboussin, Jeff Williamson, Walter T. Ambrosius, William Applegate, Greg Evans, Capri Foy, Dalane Kitzman, Mary Lyles, Nick Pajewski, Steve Rapp, Scott Rushing, Neel Shah, Kaycee M. Sink, Mara Vitolins, Lynne Wagenknecht, Valerie Wilson, Letitia Perdue, Nancy Woolard, Tim Craven, Katelyn Garcia, Laura Lovato, Jill Newman, James Lovato, Lingyi Lu, Chris McLouth, Greg Russell, Bobby Amoroso, Patty Davis, Jason Griffin, Darrin Harris, Mark King, Kathy Lane, Wes Roberson, Debbie Steinberg, Donna Ashford, Phyllis Babcock, Dana Chamberlain, Vickie Christensen, Loretta Cloud, Christy Collins, Delilah Cook, Katherine Currie, Debbie Felton, Stacy Harpe, Marjorie Howard, Michelle Lewis, Pamela Nance, Nicole Puccinelli-Ortega, Laurie Russell, Jennifer Walker, Brenda Craven, Candace Goode, Margie Troxler, Janet Davis, Sarah Hutchens, Anthony A. Killeen, Anna M. Lukkari, Robert Ringer, Brandi Dillard, Norbert Archibeque, Stuart Warren, Mike Sather, James Pontzer, Zach Taylor, Elsayed Z. Soliman, Zhu-Ming Zhang, Yabing Li, Chuck Campbell, Susan Hensley, Julie Hu, Lisa Keasler, Mary Barr, Tonya Taylor, Christos Davatzikos, Ilya Nasarallah, Lisa Desiderio, Mark Elliott, Ari Borthakur, Harsha Battapady, Guray Erus, Alex Smith, Ze Wang, Jimit Doshi, Jackson T. Wright, Mahboob Rahman, Alan J. Lerner, Carolyn Still, Alan Wiggers, Sara Zamanian, Alberta Bee, Renee Dancie, George Thomas, Martin Schreiber, Sankar Dass Navaneethan, John Hickner, Michael Lioudis, Michelle Lard, Susan Marczewski, Jennifer Maraschky, Martha Colman, Andrea Aaby, Stacey Payne, Melanie Ramos, Carol Horner, Paul Drawz, Pratibha P. Raghavendra, Scott Ober, Ronda Mourad, Muralidhar Pallaki, Peter Russo, Pratibha Raghavendra, Pual Fantauzzo, Lisa Tucker, Bill Schwing, John R. Sedor, Edward J. Horwitz, Jeffrey R. Schellling, John F. O’Toole, Lisa Humbert, Wendy Tutolo, Suzanne White, Alishea Gay, Walter Clark, Robin Hughes, Mirela Dobre, Carolyn H. Still, Monique Williams, Udayan Bhatt, Lee Hebert, Anil Agarwal, Melissa Brown Murphy, Nicole Ford, Cynthia Stratton, Jody Baxter, Alicia A. Lykins, Alison McKinley Neal Leena Hirmath, Osei Kwame, Kyaw Soe, William F. Miser, Colleen Sagrilla, Jan Johnston, Amber Anaya, Ashley Mintos, Angel A. Howell, Kelly Rogers, Sara Taylor, Donald Ebersbacher, Lucy Long, Beth Bednarchik, Adrian Schnall, Jonathan Smith, Lori Peysha, Lisa Leach, Megan Tribout, Carla Harwell, Pinkie Ellington, Mary Ann Banerji, Pranav Ghody, Melissa Vahídeh Rambaud, Raymond Townsend, Debbie Cohen, Yonghong Huan, Mark Duckworth, Virginia Ford, Juliet Leshner, Ann Davison, Sarah Vander Veen, Crystal A. Gadegbeku, Avi Gillespie, Anuradha Paranjape, Sandra Amoroso, Zoe Pfeffer, Sally B. Quinn, Jiang He, Jing Chen, Eva Lustigova, Erin Malone, Marie Krousel-Wood, Richard Deichmann, Patricia Ronney, Susan Muery, Donnalee Trapani, Michael Rocco, David Goff, Carlos Rodriguez, Laura Coker, Amret Hawfield, Joseph Yeboah, Lenore Crago, John Summerson, Anita Hege, Matt Diamond, Laura Mulloy, Marcela Hodges, Michelle Collins, Charlene Weathers, Heather Anderson, Emily Stone, Walida Walker, Andrew McWilliams, Michael Dulin, Lindsay Kuhn, Susan Standridge, Lindsay Lowe, Kelly Everett, Kelry Preston, Susan Norton, Silena Gaines, Ali A. Rizvi, Andrew W. Sides, Diamond Herbert, Matthew M. Hix, Melanie Whitmire, Brittany Arnold, Philip Hutchinson, Joseph Espiritu, Mark Feinglos, Eugene Kovalik, Georgianne Gedon-Lipscomb, Kathryn Evans, Connie Thacker, Ronna Zimmer, Mary Furst, MaryAnn Mason, James Powell, Paul Bolin, Junhong Zhang, Mary Pinion, Gail Davis, Winifred Bryant, Presley Phelps, Connie Garris-Sutton, Beatrice Atkinson, Gabriele Contreras, Maritza Suarez, Ivonne Schulman, Don Koggan, Jackie Vassallo, Gloria Peruyera, Sheri Whittington, Cassandra Bethea, Laura Gilliam, Carolyn Pedley, Geraldine Zurek, Miriam Baird, Charles Herring, Mary Martha Smoak, Julie Williams, Samantha Rogers, Lindsay Gordon, Erin Kennedy, Beverly Belle, Jessica McCorkle-Doomy, Jonathan Adams, Ramon Lopez, Juris Janavs, Frederic Rahbari-Oskoui, Arlene Chapman, Allen Dollar, Olubunmi Williams, Yoosun Han, William Haley, Peter Fitzpatrick, Joseph Blackshear, Brian Shapiro, Anna Harrell, Arta Palaj, Katelyn Henderson, Ashley Johnson, Heath Gonzalez, Jermaine Robinson, Leonardo Tamariz, Jennifer Denizard, Rody Barakat, Dhurga Krishnamoorthy, Frank Greenway, Ron Monce, Timothy Church, Chelsea Hendrick, Aimee Yoches, Leighanne Sones, Markee Baltazar, Priscilla Pemu, Connie Jones, Derrick Akpalu, Gordon Chelune, Jeffrey Childs, Lisa Gren, Anne Randall, Laura Dember, Denise Soares, Jerry Yee, Kausik Umanath, Naima Ogletree, Schawana Thaxton, Karen Campana, Dayna Sheldon, Krista MacArthur, J. Brent Muhlestein, Nathan Allred, Brian Clements, Ritesh Dhar, Kent Meredith, Viet Le, Edward Miner, James Orford, Erik R. Riessen, Becca Ballantyne, Ben Chisum, Kevin Johnson, Dixie Peeler, Glenn Chertow, Manju Tamura, Tara Chang, Kevin Erickson, Jenny Shen, Randall S. Stafford, Gregory Zaharchuk, Margareth Del Cid, Michelle Dentinger, Jennifer Sabino, Rukmani Sahay, Ekaterina Telminova, Daniel E. Weiner, Mark Sarnak, Lily Chan, Amanda Civiletto, Alyson Heath, Amy Kantor, Priyanka Jain, Bethany Kirkpatrick, Andrew Well, Barry Yuen, Michel Chonchol, Beverly Farmer, Heather Farmer, Carol Greenwald, Mikaela Malaczewski, James Lash, Anna Porter, Ana Ricardo, Robert T. Rosman, Janet Cohan, Nieves Lopez Barrera, Daniel Meslar, Patricia Meslar, Margaret Conroy, Mark Unruh, Rachel Hess, Manisha Jhamb, Holly Thomas, Pam Fazio, Elle Klixbull, Melissa Komlos-Weimer, LeeAnne Mandich, Tina Vita, Robert Toto, Peter Van Buren, Julia Inrig, Martha Cruz, Tammy Lightfoot, Nancy Wang, Lori Webster, Kalani Raphael, Barry Stults, Tahir Zaman, Debra Simmons, Tooran Lavasani, Rebecca Filipowicz, Guo Wei, Gracie Mary Miller, Jenice Harerra, Jeff Christensen, Ajay Giri, Xiaorui Chen, Natalie Anderton, Arianna Jensen, Julia Lewis, Anna Burgner, Jamie P. Dwyer, Gerald Schulman, Terri Herrud, Ewanda Leavell, Tiffany McCray, Edwina McNeil-Simaan, Munmun Poudel, Malia Reed, Mohammed Sika, Delia Woods, Janice L. Zirkenbach, Dominic S. Raj, Scott Cohen, Samir Patel, Manuel Velasquez, Roshni S. Bastian, Maria Wing, Akshay Roy-Chaudhury, Thomas Depner, Lorien Dalyrymple, George Kaysen, Susan Anderson, John Nord, Joachim H. Ix, Leonard Goldenstein, Cynthia M. Miracle, Nketi Forbang, Maja Mircic, Brenda Thomas, Tiffany Tran, Anjay Rastogi, Mihae Kim, Mohamad Rashid, Bianca Lizarraga, Amy Hocza, Kristine Sarmosyan, Jason Norris, Tushar Sharma, Amanda Chioy, Eric Bernard, Eleanore Cabrera, Christina Lopez, Susana Nunez, Joseph Riad, Suzanne Schweitzer, Siran Sirop, Sarah Thomas, Lauren Wada, Holly Kramer, Vinod Bansal, Corliss E. Taylor, Mark S. Segal, Karen L. Hall, Amir Kazory, Lesa Gilbert, Linda Owens, Danielle Poulton, Elaine Whidden, Jocelyn Wiggins, Caroline Blaum, Linda Nyquist, Lillian Min, Tanya Gure, Ruth Lewis, Jennifer Mawby, Eileen Robinson, Cora E. Lewis, Virginia Bradley, David Calhoun, Stephen Glasser, Kim Jenkins, Tom Ramsey, Nauman Qureshi, Karen Ferguson, Sumrah Haider, Mandy James, Christy Jones, Kim Renfroe, April Seay, Carrie Weigart, Denyse Thornley-Brown, Dana Rizik, Bari Cotton, Meredith Fitz-Gerald, Tiffany Grimes, Carolyn Johnson, Sara Kennedy, Chanel Mason, Lesa Rosato-Burson, Robin Willingham, Eric Judd, Tonya Breaux-Shropshire, Felice Cook, Julia Medina, Lama Ghazi, Hemal Bhatt, James Lewis, Roman Brantley, John Brouilette, Jeffrey Glaze, Stephanie Hall, Nancy Hiott, David Tharpe, Spencer Boddy, Catherine Mack, Catherine Womack, Keiko Asao, Beate Griffin, Carol Hendrix, Karen Johnson, Lisa Jones, Chelsea Towers, Henry Punzi, Kathy Cassidy, Kristin Schumacher, Carmen Irizarry, Ilma Colon, Pedro Colon-Ortiz, Pedro J. Colón-Hernández, Orlando J. Carrasquillo-Navarro, Merari Carrasquillo, Nivea Vazquez, Miguel Sosa-Padilla, Alex Cintron-Pinero, Mayra Ayala, Olga Pacheco, Catalina Rivera, Irma Sotomayor-Gonzalez, Jamie Claudio, Jose Lazaro, Migdalia Arce, Lourdes Heres, Alba Perez, Jose Tavarez-Valle, Ferlinda Arocho, Mercedes Torres, Melvaliz Vazquez, Gerard P. Aurigemma, Rebecca Takis-Smith, Julia Andrieni, Noelle Bodkin, Kiran Chaudhary, Paula Hu, John Kostis, Nora Cosgrove, Denise Bankowski, Monica Boleyn, Laurie Casazza, Victoria Giresi, Tosha Patel, Erin Squindo, Yan Wu, Zeb Henson, Marion Wofford, Jessica Lowery, Deborah Minor, Kimberley Harkins, Alexander Auchus, Michael Flessner, Cathy Adair, Jordan Asher, Debbie Loope, Rita Cobb, Reiner Venegas, Thomas Bigger, Natalie Bello, Shunichi Homma, Daniel Donovan, Carlos Lopez-Jimenez, Amilcar Tirado, Asqual Getaneh, Rocky Tang, Sabrina Durant, Mathew Maurer, Sergio Teruya, Stephen Helmke, Julissa Alvarez, Ruth Campbell, Roberto Pisoni, Rachel Sturdivant, Deborah Brooks, Caroline Counts, Vickie Hunt, Lori Spillers, Donald Brautigam, Timothy Kitchen, Timothy Gorman, Jessica Sayers, Sarah Button, June Chiarot, Rosemary Fischer, Melissa Lyon, Maria Resnick, Nicole Hodges, Jennifer Ferreira, William Cushman, Barry Wall, Linda Nichols, Robert Burns, Jennifer Martindale-Adams, Dan Berlowitz, Elizabeth Clark, Sandy Walsh, Terry Geraci, Carol Huff, Linda Shaw, Karen Servilla, Darlene Vigil, Terry Barrett, Mary Ellen Sweeney, Rebecca Johnson, Susan McConnell, Khadijeh Shahid Salles, Francoise Watson, Cheryl Schenk, Laura Whittington, Maxine Maher, Jonathan Williams, Stephen Swartz, Paul Conlin, George Alexis, Rebecca Lamkin, Patti Underwood, Helen Gomes, Clive Rosendorff, Stephen Atlas, Saadat Khan, Waddy Gonzalez, Samih Barcham, Lawrence Kwon, Matar Matar, Anwar Adhami, Jan Basile, Joseph John, Deborah Ham, Hadi Baig, Mohammed Saklayen, Jason Yap, Helen Neff, Carol Miller, Ling Zheng-Phelan, Saib Gappy, Shiva Rau, Arathi Raman, Vicki Berchou, Elizabeth Jones, Erin Olgren, Cynthia Marbury, Michael Yudd, Sithiporn Sastrasinh, Jennine Michaud, Jessica Fiore, Marianne Kutza, Ronald Shorr, Rattana Mount, Helen Dunn, Susan Stinson, Jessica Hunter, Addison Taylor, Jeffery Bates, Catherine Anderson, Kent Kirchner, Jodi Stubbs, Ardell Hinton, Anita Spencer, Santosh Sharma, Thomas Wiegmann, Smita Mehta, Michelle Krause, Kate Dishongh, Richard Childress, Geeta Gyamlani, Atossa Niakan, Cathy Thompson, Janelle Moody, Carolyn Gresham, Jeffrey Whittle, Gary Barnas, Dawn Wolfgram, Heidi Cortese, Jonette Johnson, Christianne Roumie, Adriana Hung, Jennifer Wharton, Kurt Niesner, Lois Katz, Elizabeth Richardson, George Brock, Joanne Holland, Troy Dixon, Athena Zias, Christine Spiller, Penelope Baker, James Felicetta, Shakaib Rehman, Kelli Bingham, Suzanne Watnick, David Cohen, Jessica Weiss, Tera Johnston, Stephen Giddings, Hala Yamout, Andrew Klein, Caroline Rowe, Kristin Vargo, Kristi Waidmann, Vasilios Papademetriou, Jean Pierre Elkhoury, Barbara Gregory, Susan Amodeo, Mary Bloom, Dalia Goldfarb-Waysman, Richard Treger, Mehran Kashefi, Christina Huang, Karen Knibloe, Areef Ishani, Yelena Slinin, Christine Olney, Jacqueline Rust, Paolo Fanti, Christopher Dyer, Shweta Bansal, Monica Dunnam, Lih-Lan Hu, and Perla Zarate-Abbott
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Male ,medicine.medical_specialty ,Renal function ,Perfusion scanning ,Blood Pressure ,Article ,chemistry.chemical_compound ,Internal medicine ,medicine ,Humans ,Cerebral perfusion pressure ,Renal Insufficiency, Chronic ,Antihypertensive Agents ,Aged ,Creatinine ,business.industry ,medicine.disease ,Perfusion ,Blood pressure ,chemistry ,Cerebral blood flow ,Nephrology ,Cerebrovascular Circulation ,Hypertension ,Albuminuria ,Cardiology ,Female ,medicine.symptom ,business ,Kidney disease ,Glomerular Filtration Rate - Abstract
RATIONALE AND OBJECTIVE: The safety of intensive blood pressure (BP) targets is controversial for persons with chronic kidney disease (CKD). We studied the effects of hypertension treatment on cerebral perfusion and structure in those with and without CKD. STUDY DESIGN: Neuroimaging substudy of a randomized trial. SETTING & PARTICIPANTS: A subset of participants in the Systolic Blood Pressure Intervention Trial who underwent brain MRI studies. Presence of baseline CKD was assessed by estimated glomerular filtration rate (eGFR) and urine albumin to creatinine ratio (UACR). INTERVENTION: Participants were randomly assigned to intensive (systolic BP 30 mg/g (N=151), the effects of intensive versus standard BP treatment on change in global cerebral blood flow, WMLs and total brain volume were 1.91 ml/100g/min (95% CI −3.01, 6.82), 0.003 cm(3) (asinh transformed, 95% CI −0.13, 0.13), and −7.0 cm(3) (95% CI −13.3, −0.3), respectively. The overall treatment effects on cerebral blood flow and total brain volume were not modified by baseline eGFR or UACR; however the effect on WMLs was attenuated in participants with albuminuria (interaction p-value 0.04). LIMITATIONS: Measurement variability due to multi-site design. CONCLUSIONS: Among hypertensive adults with primarily early kidney disease, intensive versus standard blood pressure treatment did not appear to have a detrimental effect on brain perfusion or structure. The findings support the safety of intensive blood pressure treatment targets on brain health in persons with early kidney disease. FUNDING: The Systolic Blood Pressure Intervention Trial was funded by the National Institutes of Health (including the National Heart, Lung, and Blood Institute, the National Institute of Diabetes and Digestive and Kidney Diseases, the National Institute on Aging, and the National Institute of Neurological Disorders and Stroke), and this substudy was funded by the National Institutes of Diabetes and Digestive and Kidney Diseases. TRIAL REGISTRATION: SPRINT was registered at ClinicalTrials.gov with the study number NCT01206062.
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- 2021
38. Barriers and Facilitators to Implementing Reduced-Sodium Salts as a Population-Level Intervention: A Qualitative Study
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Hongling Chu, Mark D. Huffman, Kathy Trieu, Hueiming Liu, Sallie-Anne Pearson, J. Jaime Miranda, Maoyi Tian, Lingli Sun, Bruce Neal, Xuejun Yin, Jason H Y Wu, Jacqui Webster, Laura K. Cobb, and Matti Marklund
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Male ,salt substitute ,program impact ,Population level ,data analysis ,key informant interview ,qualitative study ,BLOOD-PRESSURE ,information dissemination ,Sodium Chloride ,Global Health ,Profit (economics) ,Nutrition Policy ,saltiness ,chemistry.chemical_compound ,Manufacturing ,cost ,program sustainability ,SUBSTITUTES ,TX341-641 ,sodium ,Qualitative Research ,clinical article ,Nutrition and Dietetics ,product market ,Data Collection ,Salt substitute ,potassium ,government ,blood pressure regulation ,Public Health, Global Health, Social Medicine and Epidemiology ,price ,health care planning ,Näringslära ,female ,Female ,sodium reduction ,Life Sciences & Biomedicine ,sodium intake ,safety ,UNITED-STATES ,World Health Organization ,CHINA ,Article ,Supply and demand ,low-sodium salt ,male ,Environmental health ,reduced-sodium salt ,Humans ,human ,program effectiveness ,METAANALYSIS ,Government ,Science & Technology ,Nutrition & Dietetics ,business.industry ,Nutrition. Foods and food supply ,Sodium, Dietary ,Diet ,semi structured interview ,REDUCTION ,manufacturing ,Intervention (law) ,Folkhälsovetenskap, global hälsa, socialmedicin och epidemiologi ,chemistry ,manufacturing industry ,1111 Nutrition and Dietetics ,business ,0908 Food Sciences ,qualitative research ,Food Analysis ,Food Science ,Qualitative research - Abstract
Widespread use of reduced-sodium salts can potentially lower excessive population-level dietary sodium intake. This study aimed to identify key barriers and facilitators to implementing reduced-sodium salt as a population level intervention. Semi-structured interviews were conducted with key informants from academia, the salt manufacturing industry, and government. We used the reach, effectiveness, adoption, implementation, and maintenance (RE-AIM) framework to inform our interview guides and data analysis. Eighteen key informants from nine countries across five World Health Organization regions participated in the study from January 2020 to July 2020. Participants were concerned about the lack of robust evidence on safety for specific populations such as those with renal impairment. Taste and price compared to regular salt and an understanding of the potential health benefits of reduced-sodium salt were identified as critical factors influencing the adoption of reduced-sodium salts. Higher production costs, low profit return, and reduced market demand for reduced-sodium salts were key barriers for industry in implementation. Participants provided recommendations as potential strategies to enhance the uptake. There are presently substantial barriers to the widespread use of reduced-sodium salt but there are also clear opportunities to take actions that would increase uptake.
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- 2021
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39. The contribution of insects to global forest deadwood decomposition
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David B. Lindenmayer, Michael D. Ulyshen, Wolfgang W. Weisser, Hassan Barimani Varandi, Jacques S. Rakotondranary, Jacques Beauchêne, Romina Daiana Fernandez, Gergely Boros, Jean-Baptiste Ramanamanjato, Stephen M. Pawson, Joakim Hjältén, Petr Baldrian, Grizelle González, Erika Berenguer, Jari Kouki, Naili Zhang, Hervé Brustel, Torsten Hothorn, Sung-Soo Yoon, John O'Halloran, Yu Liu, Sharif A. Mukul, Byambagerel Suran, Philip J. Burton, Pablo E. Martina, Liana Chesini Rossi, Sebastian Seibold, Jürgen Schmidl, Stefan Hotes, Tyler P. Cobb, Janina Lorz, Kurtis Nisbet, Jorge Castro, Stephen Seaton, Anne Oxbrough, Roxana Aragón, Jennifer Firn, Werner Rammer, Roland Brandl, Thibault Lachat, Tone Birkemoe, Jos Barlow, Nina Farwig, Mark Schulze, Martin M. Gossner, Jeev Nath Pandey, Soyeon Bae, Ya-Huang Luo, Simon Thorn, Baatarbileg Nachin, Tim Wardlaw, Kee Seng Gan, Yvonne Tété Cakpo-Tossou, Jie Liu, Claus Bässler, Ganesh Thyagarajan, Yagya Prasad Adhikari, Damasa M. Macandog, Claudia Hemp, Tomáš Pavlíček, Osmo Heikkala, Jan Christian Habel, Marisa J. Stone, Christian Hébert, Christoph Heibl, Nigel E. Stork, Rupert Seidl, Rodrigo Scarton Bergamin, Eugénie Cateau, Jörg Müller, Andreas Hemp, Anne Sverdrup-Thygeson, Marc W. Cadotte, Technical University of Munich (TUM), Institute of Silviculture, Department of Forest and Soil Sciences, Universität für Bodenkultur Wien [Vienne, Autriche] (BOKU), Helmholtz Zentrum für Umweltforschung = Helmholtz Centre for Environmental Research (UFZ), University of Natural Resources and Life Sciences (BOKU), USDA Forest Service Rocky Mountain Forest and Range Experiment Station, United States Department of Agriculture (USDA), Field Station Fabrikschleichach, Julius-Maximilians-Universität Würzburg [Wurtzbourg, Allemagne] (JMU), University of Toronto [Scarborough, Canada], Climate Change Institute at the Australian National University, Australian National University (ANU), University of Bayreuth, Instituto Argentino de Nivología, Glaciología y Ciencias Ambientales [Mendoza] (CONICET-IANIGLA), Consejo Nacional de Investigaciones Científicas y Técnicas [Buenos Aires] (CONICET)-Universidad Nacional de Cuyo [Mendoza] (UNCUYO), University of Würzburg, Institute of Microbiology of the Czech Academy of Sciences (MBU / CAS), Czech Academy of Sciences [Prague] (CAS), University of Mazandaran, Lancaster Environment Centre, Lancaster University, Goethe-University Frankfurt am Main, Ecologie des forêts de Guyane (UMR ECOFOG), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-AgroParisTech-Université de Guyane (UG)-Centre National de la Recherche Scientifique (CNRS)-Université des Antilles (UA)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), Département Environnements et Sociétés (Cirad-ES), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad), Federal University of Rio Grande do Sul, Norwegian University of Life Sciences (NMBU), CENTRE FOR ECOLOGICAL RESEARCH VACRATOT HUN, Partenaires IRSTEA, Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA), Philipps University of Marburg, Dynamiques et écologie des paysages agriforestiers (DYNAFOR), École nationale supérieure agronomique de Toulouse [ENSAT]-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), University of Northern British Columbia [Prince George] (UNBC), University of Abomey Calavi (UAC), University of Granada [Granada], Réserves Naturelles de France, Royal Alberta Museum, Consejo Nacional de Investigaciones Científicas y Técnicas [Buenos Aires] (CONICET), Queensland University of Technology [Brisbane] (QUT), Forest Research Institute Malaysia (FRIM), Swiss Federal Institute for Forest, Snow and Landscape Research WSL, University of Salzburg, Canadian Forest Service - CFS (CANADA), Bavarian Forest National Park, Eurofins Ahma Oy, Technische Universität Munchen - Université Technique de Munich [Munich, Allemagne] (TUM), Technical University of Munich, Berchtesgaden National Park, University of Zurich, USDA Forest Service, University of Toronto Scarborough, The Australian National University, CONICET-Universidad Nacional de Tucumán, The Czech Academy of Sciences, Agricultural and Natural Resources Research Centre of Mazandaran, Universidade Federal de Lavras (UFLA), Goethe-University Frankfurt, Universite de Guyane, University of Oxford, Norwegian University of Life Sciences, Centre for Ecological Research, Hungarian University of Agriculture and Life Sciences, University of Marburg, UMR 1201 Dynafor, University of Northern British Columbia, University of Abomey-Calavi, University of Granada, Queensland University of Technology, Institute for Future Environments, Forest Research Institute Malaysia, Swiss Federal Research Institute WSL, Canadian Forest Service, Swedish University of Agricultural Sciences, Chuo University, University of Eastern Finland, Bern University of Applied Sciences, Chinese Academy of Sciences, East China Normal University, University of the Philippines Los Banos, Universidad Nacional del Nordeste, University of the Sunshine Coast, National University of Mongolia, Griffith University, University College Cork, Edge Hill University, Tribhuvan University, University of Haifa, Scion (New Zealand Forest Research Institute), University of Canterbury, University of Hamburg, Université d’Antananarivo, Tropical Biodiversity and Social Enterprise, Universidade Estadual Paulista (UNESP), University Erlangen-Nuremberg, H. J. Andrews Experimental Forest, Murdoch University, Ashoka Trust for Research in Ecology and the Environment, University of Tasmania, National Institute of Ecology, and Beijing Forestry University
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0106 biological sciences ,Carbon Sequestration ,Insecta ,010504 meteorology & atmospheric sciences ,Climate ,International Cooperation ,chemistry.chemical_element ,Geographic Mapping ,Forests ,Atmospheric sciences ,010603 evolutionary biology ,01 natural sciences ,Decomposer ,Carbon cycle ,Carbon Cycle ,Trees ,Forest ecology ,Temperate climate ,Animals ,Ecosystem ,0105 earth and related environmental sciences ,[SDV.EE]Life Sciences [q-bio]/Ecology, environment ,Multidisciplinary ,Taiga ,15. Life on land ,Decomposition ,Deadwood ,Insects ,chemistry ,13. Climate action ,Environmental science ,Ecosystem ecology ,Carbon - Abstract
Made available in DSpace on 2022-04-28T19:44:08Z (GMT). No. of bitstreams: 0 Previous issue date: 2021-09-02 The amount of carbon stored in deadwood is equivalent to about 8 per cent of the global forest carbon stocks1. The decomposition of deadwood is largely governed by climate2–5 with decomposer groups—such as microorganisms and insects—contributing to variations in the decomposition rates2,6,7. At the global scale, the contribution of insects to the decomposition of deadwood and carbon release remains poorly understood7. Here we present a field experiment of wood decomposition across 55 forest sites and 6 continents. We find that the deadwood decomposition rates increase with temperature, and the strongest temperature effect is found at high precipitation levels. Precipitation affects the decomposition rates negatively at low temperatures and positively at high temperatures. As a net effect—including the direct consumption by insects and indirect effects through interactions with microorganisms—insects accelerate the decomposition in tropical forests (3.9% median mass loss per year). In temperate and boreal forests, we find weak positive and negative effects with a median mass loss of 0.9 per cent and −0.1 per cent per year, respectively. Furthermore, we apply the experimentally derived decomposition function to a global map of deadwood carbon synthesized from empirical and remote-sensing data, obtaining an estimate of 10.9 ± 3.2 petagram of carbon per year released from deadwood globally, with 93 per cent originating from tropical forests. Globally, the net effect of insects may account for 29 per cent of the carbon flux from deadwood, which suggests a functional importance of insects in the decomposition of deadwood and the carbon cycle. Ecosystem Dynamics and Forest Management Group School of Life Sciences Technical University of Munich Berchtesgaden National Park Epidemiology Biostatistics and Prevention Institute University of Zurich Southern Research Station USDA Forest Service Field Station Fabrikschleichach University of Würzburg Biological Sciences University of Toronto Scarborough Fenner School of Environment and Society The Australian National University Department of Biogeography University of Bayreuth Department of Disturbance Ecology University of Bayreuth Instituto de Ecología Regional CONICET-Universidad Nacional de Tucumán Department of Animal Ecology and Tropical Biology University of Würzburg Laboratory of Environmental Microbiology Institute of Microbiology The Czech Academy of Sciences Agricultural and Natural Resources Research Centre of Mazandaran Lancaster Environment Centre Lancaster University Universidade Federal de Lavras Department of Biodiversity Conservation Goethe-University Frankfurt Bavarian Forest National Park CIRAD UMR Ecologie des Forêts de Guyane (EcoFoG) AgroParisTech CNRS INRA Universite des Antilles Universite de Guyane Environmental Change Institute University of Oxford Grassland Vegetation Lab Federal University of Rio Grande do Sul Faculty of Environmental Sciences and Natural Resource Management Norwegian University of Life Sciences Institute of Ecology and Botany Centre for Ecological Research Institute for Wildlife Management and Nature Conservation Hungarian University of Agriculture and Life Sciences Animal Ecology University of Marburg École d’Ingénieurs de Purpan Université de Toulouse UMR 1201 Dynafor Ecosystem Science and Management Program University of Northern British Columbia Laboratory of Applied Ecology University of Abomey-Calavi Department of Ecology University of Granada Réserves Naturelles de France Royal Alberta Museum Conservation Ecology University of Marburg Science and Engineering Faculty Queensland University of Technology Centre for the Environment Institute for Future Environments Forest Research Institute Malaysia International Institute of Tropical Forestry USDA Forest Service Forest Entomology Swiss Federal Research Institute WSL Evolutionary Zoology University of Salzburg Natural Resources Canada Canadian Forest Service Eurofins Ahma Oy Department of Plant Systematics University of Bayreuth Department of Wildlife Fish and Environmental Studies Swedish University of Agricultural Sciences Applied Landscape Ecology Chuo University School of Forest Sciences University of Eastern Finland School of Agricultural Forest and Food Sciences Bern University of Applied Sciences CAS Key Laboratory for Plant Diversity and Biogeography of East Asia Kunming Institute of Botany Chinese Academy of Sciences ECNU-Alberta Joint Lab for Biodiversity Study Tiantong National Station for Forest Ecosystem Research East China Normal University Institute of Biological Sciences University of the Philippines Los Banos Department of Thermodynamics Universidad Nacional del Nordeste Tropical Forests and People Research Centre University of the Sunshine Coast Forest Ecosystem Monitoring Laboratory National University of Mongolia School of Environment and Science Griffith University School of Biological Earth and Environmental Sciences University College Cork Edge Hill University Institute of Forestry Tribhuvan University Institute of Evolution University of Haifa Scion (New Zealand Forest Research Institute) School of Forestry University of Canterbury Institute of Zoology University of Hamburg Faculté des Sciences Université d’Antananarivo Tropical Biodiversity and Social Enterprise Departamento de Ecologia Universidade Estadual Paulista Ecology Group University Erlangen-Nuremberg H. J. Andrews Experimental Forest Environmental and Conservation Sciences Murdoch University Environmental Futures Research Institute Griffith University Ashoka Trust for Research in Ecology and the Environment ARC Centre for Forest Value University of Tasmania Terrestrial Ecology Research Group School of Life Sciences Technical University of Munich EcoBank Team National Institute of Ecology College of Forestry Beijing Forestry University Departamento de Ecologia Universidade Estadual Paulista
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- 2021
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40. Core Strategies to Increase the Uptake and Use of Potassium-Enriched Low-Sodium Salt
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Megan E. Henry, Nicole Ide, Adefunke Ajenikoko, Amy Atun, Cheryl Anderson, Roopa Shivashankar, Alexander Thomson, Zeng Ge, Matti Marklund, and Laura K. Cobb
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Potassium intake ,hypertension ,Population level ,Potassium ,Sodium ,chemistry.chemical_element ,Salt (chemistry) ,Review ,Health Promotion ,low-sodium salt ,cardiovascular disease ,TX341-641 ,Food science ,Sodium Chloride, Dietary ,sodium ,Excess sodium ,chemistry.chemical_classification ,Nutrition and Dietetics ,Nutrition. Foods and food supply ,Dietary sodium intake ,Potassium, Dietary ,Sodium, Dietary ,Diet, Sodium-Restricted ,Näringslära ,chemistry ,sodium reduction ,Food Science ,Low sodium - Abstract
Excess sodium consumption and insufficient potassium intake contribute to high blood pressure and thus increase the risk of heart disease and stroke. In low-sodium salt, a portion of the sodium in salt (the amount varies, typically ranging from 10 to 50%) is replaced with minerals such as potassium chloride. Low-sodium salt may be an effective, scalable, and sustainable approach to reduce sodium and therefore reduce blood pressure and cardiovascular disease at the population level. Low-sodium salt programs have not been widely scaled up, although they have the potential to both reduce dietary sodium intake and increase dietary potassium intake. This article proposes a framework for a successful scale-up of low-sodium salt use in the home through four core strategies: availability, awareness and promotion, affordability, and advocacy. This framework identifies challenges and potential solutions within the core strategies to begin to understand the pathway to successful program implementation and evaluation of low-sodium salt use.
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- 2021
41. Abstract PD8-10: Efficacy and safety of enobosarm, a selective androgen receptor modulator, to target AR in women with advanced ER+/AR+ breast cancer - final results from an international Phase 2 randomized study
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Charles L. Vogel, Robert H. Getzenberg, Mitchell S. Steiner, Kirti Jain, Carlo Palmieri, Patrick Wayne Cobb, Hope S. Rugo, Elgene Lim, Adam Brufsky, Hannah M. Linden, Beth Overmoyer, Joyce O'Shaughnessy, Lee S. Schwartzberg, and Stephen N. Birrell
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Cancer Research ,business.industry ,medicine.disease ,law.invention ,chemistry.chemical_compound ,Breast cancer ,Oncology ,Randomized controlled trial ,chemistry ,Selective androgen receptor modulator ,law ,Cancer research ,Medicine ,Enobosarm ,business - Abstract
Introduction: Hormonal agents remain the most effective therapies for estrogen receptor positive (ER+) HER2- breast cancer. The androgen receptor (AR) is the most highly expressed steroid receptor found in up to 95% of ER+ breast cancer patients. Androgen agonists have antiproliferative activity in ER+ breast cancer and have been used in treatment, however their lack of availability and virilizing side effects have limited their use. Enobosarm is a non-steroidal tissue-selective AR modulator that that is being developed for AR targeted treatment of ER+/AR+ breast cancer. Methods: An international, Phase 2, open label, parallel design, randomized study was conducted in 136 patients (pts) to investigate the efficacy and safety of enobosarm in postmenopausal women with metastatic ER+/AR+ breast cancer that progressed on previous endocrine therapy. Pts were randomized to receive 9 mg (n=72) or 18 mg (n=64) of oral daily enobosarm. The primary endpoint was clinical benefit rate (CBR) at 24 weeks (defined as CR, PR or SD) by RECIST 1.1. Secondary endpoints included objective response rate, best overall response rate (BOR), progression free survival (PFS), duration of clinical benefit. Results: The study population consisted of heavily pre-treated pts with a mean of 4 (range 1-6) prior hormone therapies and >90% receiving one prior course of chemotherapy. Median age was 60.8 years (35-83) for 9 mg and 62.1 (42-81) for the 18 mg cohort. AR positivity was centrally confirmed in 73.6% and 81.2% in the 9 and 18 mg cohorts, respectively. Efficacy: In the evaluable pts, 50 in the 9 mg arm and 52 in the 18 mg arm (AR confirmed), 32% of the 9mg cohort met the primary endpoint of CBR at 24 weeks (95% CI, 19.5%; 46.7%) and 29% (95% CI, 17.1%; 43.1%) in the 18 mg cohort. The BOR was 2 CRs, 10 PRs in the 9 mg and 3 CRs,7 PRs in the 18 mg group by central review. Median PFS was 5.6 (2.9 to 27.5) and 4.2 (2.8 to 11) months (mo) in the 9 mg and 18 mg groups. The median duration of treatment was 4.0 months (0.23-30.3 months) in the 9 mg group and 3.8 months (0.5-16.7 months) in the 18 mg group. At the time the study was terminated, the median duration of clinical benefit was not reached (NR) in the 9 mg group (range 8.2 mo to NR) and 14.1 mo (range 11.0 to 16.5) in the 18 mg group. QOL: Using a standardized instrument of generic health status (EQ-5D), a significant percentage of pts reported improvement in measurements including mobility (40%, 50%), anxiety/depression (50%, 29%) and pain discomfort (50%, 31%) for the 9 and 18 mg groups, respectively. Drug related severe adverse events (SAEs) (Grades 3-4) were observed in 6 (8.0%) at the 9 mg and 10 (16.4%) at the 18 mg dose. The SAEs (Grade 3-4) attributed to the study drug by the site investigator were for the 9 mg group: fatigue (1), elevated transaminases (2), headache (1), hypercalcemia (2) and anemia (1). For the 18 mg group the drug attributable SAEs (Grade 3-4) were: dry mouth (1), increased aminotransferase (2), decreased white blood cell count (1), fatigue (2), hypercalcemia (1), decreased appetite (1), headache (1), tumor flare (2), agitation (1), lymphadenopathy (1) and acute kidney injury (1). Conclusions: In this Phase 2 parallel design study, enobosarm (9 mg and 18 mg) has significant clinical activity and was well tolerated in heavily pretreated patients with ER+/AR+ metastatic breast cancer. Given the limited options of hormonal therapy for metastatic ER+ breast cancer, enobosarm merits further clinical development in a Phase 3 clinical program as an AR targeted treatment for metastatic ER+AR+ breast cancer. Citation Format: Carlo Palmieri, Hannah Linden, Stephen Birrell, Elgene Lim, Lee S Schwartzberg, Hope S Rugo, Patrick Cobb, Kirti Jain, Charles Vogel, Joyce A O’Shaughnessy, Robert H Getzenberg, Mitchell S Steiner, Adam Brufsky, Beth Overmoyer. Efficacy and safety of enobosarm, a selective androgen receptor modulator, to target AR in women with advanced ER+/AR+ breast cancer - final results from an international Phase 2 randomized study [abstract]. In: Proceedings of the 2020 San Antonio Breast Cancer Virtual Symposium; 2020 Dec 8-11; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2021;81(4 Suppl):Abstract nr PD8-10.
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- 2021
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42. Development of Mushroom Mycelium Composites for Footwear Products
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Huantian Cao, Jillian Silverman, and Kelly Cobb
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0209 industrial biotechnology ,Mushroom ,Municipal solid waste ,Polymers and Plastics ,Chemistry ,Materials Science (miscellaneous) ,02 engineering and technology ,Substrate (biology) ,021001 nanoscience & nanotechnology ,General Business, Management and Accounting ,020901 industrial engineering & automation ,Business, Management and Accounting (miscellaneous) ,Food science ,0210 nano-technology ,Mycelium - Abstract
This research aims to reduce solid waste, resource depletion, and material toxicity in the footwear industry. Mycelium, the root structure of mushrooms, binds together substrate materials as it grows, offering opportunities for composite development. Mycelium composites were developed using edible mushroom species alongside other natural materials. The 4 × 2 experiment tested four mushroom species (reishi, oyster, king oyster, and yellow oyster) and two fabric levels (with or without a natural fabric mat). Scanning electron microscopy images confirmed mycelium growth within the composite and around the substrates. Two-way analysis of variance tests found that both species and fabric significantly affected the density, and the species significantly affected the compressive strength. A positive and significant linear relationship was found between density and compressive strength, with higher density leading to higher compressive strength. The compressive strength of the mycelium composites, especially those made from king oyster mycelium, provides opportunities for renewable and biodegradable footwear inputs.
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- 2020
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43. Anti-inflammatory coating of hernia repair meshes: a 5-rabbit study
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Dmitry Gil, Vladimir Reukov, Mikhail Bredikhin, Alexey Vertegel, William S. Cobb, and James Rex
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Vitamin ,Male ,medicine.medical_specialty ,Pathology ,Hernia ,Biocompatibility ,medicine.medical_treatment ,Anti-Inflammatory Agents ,Inflammation ,Pilot Projects ,Polypropylene mesh ,030230 surgery ,medicine.disease_cause ,Polypropylenes ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,In vivo ,medicine ,Vitamin E ,Animals ,Herniorrhaphy ,Rabbit model ,business.industry ,Abdominal Wall ,Surgical Mesh ,medicine.disease ,Hernia repair ,Surgery ,Disease Models, Animal ,chemistry ,030220 oncology & carcinogenesis ,Original Article ,Rabbits ,medicine.symptom ,business ,Oxidative stress - Abstract
Purpose Polymeric mesh implantation has become the golden standard in hernia repair, which nowadays is one of the most frequently performed surgeries in the world. However, many biocompatibility issues remain to be a concern for hernioplasty, with chronic pain being the most notable post-operative complication. Oxidative stress appears to be a major factor in the development of those complications. Lack of material inertness in vivo and oxidative environment formed by inflammatory cells result in both mesh deterioration and slowed healing process. In a pilot in vivo study, we prepared and characterized polypropylene hernia meshes with vitamin E (α-tocopherol)-a potent antioxidant. The results of that study supported the use of vitamin E as potential coating to alleviate post-surgical inflammation, but the pilot nature of the study yielded limited statistical data. The purpose of this study was to verify the observed trend of the pilot study statistically. Methods In this work, we conducted a 5-animal experiment where we have implanted vitamin E-coated and uncoated control meshes into the abdominal walls of rabbits. Histology of the mesh-adjacent tissues and electron microscopy of the explanted mesh surface were conducted to characterize host tissue response to the implanted meshes. Results As expected, modified meshes exhibited reduced foreign body reaction, as evidenced by histological scores for fatty infiltrates, macrophages, neovascularization, and collagen organization, as well as by the surface deterioration of the meshes. Conclusion In conclusion, results indicate that vitamin E coating reduces inflammatory response following hernioplasty and protects mesh material from oxidative deterioration.
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- 2020
44. Potassium-Enriched Salt Substitutes as a Means to Lower Blood Pressure
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Matti Marklund, Arlene Dalcin, Cheryl A.M. Anderson, Megan E. Henry, Raquel C. Greer, Lawrence J. Appel, and Laura K. Cobb
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Hyperkalemia ,Lower blood pressure ,Sodium ,Potassium ,Salt (chemistry) ,chemistry.chemical_element ,Blood Pressure ,030204 cardiovascular system & hematology ,Risk Assessment ,Potassium Chloride ,03 medical and health sciences ,0302 clinical medicine ,Internal Medicine ,medicine ,Humans ,030212 general & internal medicine ,Food science ,Sodium Chloride, Dietary ,chemistry.chemical_classification ,Chemistry ,Dietary sodium intake ,Diet, Sodium-Restricted ,Water-Electrolyte Balance ,Dietary Potassium ,Blood pressure ,Hypertension ,medicine.symptom - Abstract
Use of salt substitutes containing potassium chloride is a potential strategy to reduce sodium intake, increase potassium intake, and thereby lower blood pressure and prevent the adverse consequences of high blood pressure. In this review, we describe the rationale for using potassium-enriched salt substitutes, summarize current evidence on the benefits and risks of potassium-enriched salt substitutes and discuss the implications of using potassium-enriched salt substitutes as a strategy to lower blood pressure. A benefit of salt substitutes that contain potassium chloride is the expected reduction in dietary sodium intake at the population level because of reformulation of manufactured foods or replacement of sodium chloride added to food during home cooking or at the dining table. There is empirical evidence that replacement of sodium chloride with potassium-enriched salt substitutes lowers systolic and diastolic blood pressure (average net Δ [95% CI] in mm Hg: –5.58 [–7.08 to –4.09] and –2.88 [–3.93 to –1.83], respectively). The risks of potassium-enriched salt substitutes include a possible increased risk of hyperkalemia and its principal adverse consequences: arrhythmias and sudden cardiac death, especially in people with conditions that impair potassium excretion such as chronic kidney disease. There is insufficient evidence regarding the effects of potassium-enriched salt substitutes on the occurrence of hyperkalemia. There is a need for additional empirical research on the effect of increasing dietary potassium and potassium-enriched salt substitutes on serum potassium levels and the risk of hyperkalemia, as well as for robust estimation of the population-wide impact of replacing sodium chloride with potassium-enriched salt substitutes.
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- 2020
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45. The CK1α Activator Pyrvinium Enhances the Catalytic Efficiency (kcat/Km) of CK1α
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Melanie H. Cobb, Luisana Astudillo, Murray P. Deutscher, Bin Li, David J. Robbins, Anthony J. Capobianco, Chen Shen, and Ethan Lee
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0303 health sciences ,Activator (genetics) ,030302 biochemistry & molecular biology ,Wnt signaling pathway ,Casein Kinase Ialpha ,Biochemistry ,Article ,Cell biology ,Enzyme Activation ,Serine ,Pyrvinium ,Kinetics ,Pyrvinium Compounds ,03 medical and health sciences ,chemistry.chemical_compound ,HEK293 Cells ,chemistry ,Biocatalysis ,Humans ,Phosphorylation ,Casein kinase 1 ,Kinase activity ,Protein kinase A - Abstract
The serine/threonine protein kinase casein kinase 1α (CK1α) functions as a negative regulator of Wnt signaling, phosphorylating β-catenin at serine 45 (P–S45) to initiate its eventual ubiquitin-mediated degradation. We previously showed that the repurposed, FDA-approved anthelminthic drug pyrvinium potently inhibits Wnt signaling in vitro and in vivo. Moreover, we proposed that pyrvinium’s Wnt inhibitory activity was the result of its function as an activator of CK1α. An understanding of the mechanism by which pyrvinium activates CK1α is important because pyrvinium was given an orphan drug designation by the FDA to treat familial adenomatous polyposis, a precancerous condition driven by constitutive Wnt signaling. In the current study, we show that pyrvinium stimulates the phosphorylation of S45 β-catenin, a known CK1α substrate, in a cell-based assay, and does so in a dose- and time-dependent manner. Alternative splicing of CK1α results in four forms of the protein with distinct biological properties. We evaluated these splice products and identified the CK1α splice variant, CK1αS, as the form that exhibits the most robust response to pyrvinium in cells. Kinetic studies indicate that pyrvinium also stimulates the kinase activity of purified, recombinant CK1αS in vitro, increasing its catalytic efficiency (k(cat)/K(m)) toward substrates. These studies provide strong and clear mechanistic evidence that pyrvinium enhances CK1α kinase activity.
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- 2019
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46. Modulation of hepatocyte sialylation drives spontaneous fatty liver disease and inflammation
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Mark B. Jones, Douglas M. Oswald, and Brian A. Cobb
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medicine.medical_specialty ,Glycosylation ,medicine.medical_treatment ,Inflammation ,Biochemistry ,Regular Manuscripts ,Proinflammatory cytokine ,Mice ,03 medical and health sciences ,0302 clinical medicine ,Non-alcoholic Fatty Liver Disease ,Internal medicine ,Conditional gene knockout ,medicine ,Animals ,Glycoproteins ,030304 developmental biology ,Mice, Knockout ,chemistry.chemical_classification ,0303 health sciences ,business.industry ,Fatty liver ,Acute-phase protein ,medicine.disease ,Endocrinology ,medicine.anatomical_structure ,Cytokine ,chemistry ,030220 oncology & carcinogenesis ,Hepatocyte ,Hepatocytes ,medicine.symptom ,business ,Glycoprotein - Abstract
Circulatory protein glycosylation is a biomarker of multiple disease and inflammatory states and has been applied in the clinic for liver dysfunction, heart disease and diabetes. With the notable exception of antibodies, the liver produces most of the circulatory glycoproteins, including the acute phase proteins released as a function of the inflammatory response. Among these proteins is β-galactoside α2,6-sialyltransferase (ST6Gal1), an enzyme required for α2,6-linked sialylation of glycoproteins. Here, we describe a hepatocyte-specific conditional knockout of ST6Gal1 (H-cKO) using albumin promoter-driven Cre-lox recombination. We confirm the loss of circulatory glycoprotein α2,6 sialylation and note no obvious dysfunction or pathology in young H-cKO mice, yet these mice show robust changes in plasma glycoprotein fucosylation, branching and the abundance of bisecting GlcNAc and marked changes in a number of metabolic pathways. As H-cKO mice aged, they spontaneously developed fatty liver disease characterized by the buildup of fat droplets in the liver, inflammatory cytokine production and a shift in liver leukocyte phenotype away from anti-inflammatory Kupffer cells and towards proinflammatory M1 macrophages. These findings connect hepatocyte and circulatory glycoprotein sialylation to the regulation of metabolism and inflammation, potentially identifying the glycome as a new target for liver-driven disease.
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- 2019
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47. 19 F NMR Spectroscopy Tagging and Paramagnetic Relaxation Enhancement‐Based Conformation Analysis of Intrinsically Disordered Protein Complexes
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Manuel Kitzler, Steven L. Cobb, Karin Ledolter, Graham Sandford, Mate Somlyay, and Robert Konrat
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010405 organic chemistry ,MTSL ,Stereochemistry ,Organic Chemistry ,Relaxation (NMR) ,Nuclear magnetic resonance spectroscopy ,010402 general chemistry ,Intrinsically disordered proteins ,01 natural sciences ,Biochemistry ,0104 chemical sciences ,Protein–protein interaction ,chemistry.chemical_compound ,chemistry ,Structural biology ,Molecular Medicine ,Enhancer ,Molecular Biology ,DNA - Abstract
The combination of 19 F NMR spectroscopy tagging and paramagnetic relaxation enhancement (PRE) NMR spectroscopy experiments was evaluated as a versatile method to probe protein-protein interactions and conformational changes of intrinsically disordered proteins upon complex formation. The feasibility of the approach is illustrated with an application to the Myc-Max protein complex; this is an oncogenic transcription factor that binds enhancer box DNA fragments. The single cysteine residue of Myc was tagged with highly fluorinated [19 F]3,5-bis(trifluoromethyl)benzyl bromide. Structural dynamics of the protein complex were monitored through intermolecular PREs between 19 F-Myc and paramagnetic (1-oxyl-2,2,5,5-tetramethyl-Δ3-pyrroline-3-methyl)methanethiosulfonate (MTSL)-tagged) Max. The 19 F R2 relaxation rates obtained with three differently MTSL-tagged Max mutants revealed novel insights into the differential structural dynamics of Myc-Max bound to DNA and the tumour suppressor breast cancer antigen 1. Given its ease of implementation, fruitful applications of this strategy to structural biology and inhibitor screening can be envisaged.
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- 2019
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48. Aluminum Metal Digestion as a Demonstration of an Oscillating Voltage Reaction: An Application Beyond the Textbook
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Monty L. Fetterolf, Cathy L. Cobb, and Wilson Haddock
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Materials science ,chemistry.chemical_element ,General Chemistry ,Electrochemistry ,Chloride ,Rod ,Education ,chemistry.chemical_compound ,chemistry ,Chemical engineering ,Nitric acid ,Aluminium ,Voltmeter ,General chemistry ,medicine ,Voltage ,medicine.drug - Abstract
The oscillating open-circuit voltage generated by the digestion of aluminum rods, catalyzed by copper(II) chloride in 3 M nitric acid at 90 °C, is presented as a demonstration appropriate for a general chemistry or advanced laboratory. This demonstration encourages discussion of the possible kinetic mechanism as well as the general electrochemical half-reactions involved and the limited conditions under which oscillations occur. The objective is to provide general chemistry students with an interesting reaction beyond typical kinetics or electrochemistry. Apart from 1100-alloy aluminum rods and a recording voltmeter, the demonstration uses standard lab equipment, and the materials for the solutions are those typically found in a general lab setting.
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- 2019
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49. Abundances and concentrations of brominated azo dyes detected in indoor dust
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Birendra Dhungana, John P. Giesy, Steven Kutarna, George P. Cobb, Paul D. Jones, Jing Liu, Sujan Shrestha, Bikram Subedi, Gisela de Aragão Umbuzeiro, and Hui Peng
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010504 meteorology & atmospheric sciences ,Nitrogen ,Health, Toxicology and Mutagenesis ,010501 environmental sciences ,Toxicology ,Mass spectrometry ,complex mixtures ,01 natural sciences ,Tandem Mass Spectrometry ,Halogenated Diphenyl Ethers ,Humans ,Health risk ,Child ,Flame Retardants ,0105 earth and related environmental sciences ,Aniline Compounds ,Chemistry ,Dust ,Child Day Care Centers ,General Medicine ,Pollution ,Hydrocarbons, Brominated ,Air Pollution, Indoor ,Environmental chemistry ,Azo Compounds ,Chromatography, Liquid - Abstract
Dust samples were collected from four indoor environments, including childcare facilities, houses, hair salons, and a research facility from the USA and were analyzed for brominated compounds using full scan liquid chromatography high-resolution mass spectrometry. A total of 240 brominated compounds were detected in these dust samples, and elemental formulas were predicted for 120 more abundant ions. In addition to commonly detected brominated flame retardants (BFRs), nitrogen-containing brominated azo dyes (BADs) were among the most frequently detected and abundant. Specifically, greater abundances of BADs were detected in indoor dusts from daycares and salons compared to houses and the research facility. Using authentic standards, a quantitative method was established for two BADs (DB373: Disperse Blue 373 and DV93: Disperse Violet 93) and 2-bromo-4,6-dinitroaniline, a commonly used precursor in azo dye production, in indoor dust. Generally, greater concentrations of DB373 (≤3850 ng/g) and DV93 (≤1190 ng/g) were observed in indoor dust from daycares highlighting children as a susceptible population to potential health risk from exposure to BADs. These data are important because, to date, targeted analysis of brominated compounds in indoor environments has focused mainly on BFRs and appears to underestimate the total amount of brominated compounds.
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- 2019
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50. Thyroid hormone levels associate with exposure to polychlorinated biphenyls and polybrominated biphenyls in adults exposed as children
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Victoria S. Jiang, Jessica B. Spencer, Michael F. Neblett, Michele Marcus, Melanie H. Jacobson, M. Elizabeth Marder, Metrecia L. Terrell, Dawayland O. Cobb, Alicia K. Smith, Karen N. Conneely, Sabrina A. Gerkowicz, Sarah W. Curtis, and Dana B. Barr
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Male ,Michigan ,PBB ,Health, Toxicology and Mutagenesis ,Thyroid-stimulating hormone ,Physiology ,010501 environmental sciences ,01 natural sciences ,chemistry.chemical_compound ,0302 clinical medicine ,Endocrine disrupting compound ,Medicine ,Triiodothyronine ,PCB ,lcsh:Public aspects of medicine ,DOHaD ,Thyroid ,Children’s health ,Middle Aged ,Polychlorinated Biphenyls ,3. Good health ,medicine.anatomical_structure ,lcsh:Industrial medicine. Industrial hygiene ,Female ,Thyroid function ,Adult ,Thyroid Hormones ,Polybrominated biphenyl ,Polybrominated Biphenyls ,030209 endocrinology & metabolism ,03 medical and health sciences ,lcsh:RC963-969 ,Age at exposure ,Humans ,Aged ,0105 earth and related environmental sciences ,business.industry ,Research ,Public Health, Environmental and Occupational Health ,Polychlorinated biphenyl ,lcsh:RA1-1270 ,Environmental Exposure ,Thyroxine ,Cross-Sectional Studies ,chemistry ,business ,Hormone ,EDC - Abstract
Background Michigan residents were directly exposed to endocrine-disrupting compounds, polybrominated biphenyl (PBB) and polychlorinated biphenyl (PCB). A growing body of evidence suggests that exposure to certain endocrine-disrupting compounds may affect thyroid function, especially in people exposed as children, but there are conflicting observations. In this study, we extend previous work by examining age of exposure’s effect on the relationship between PBB exposure and thyroid function in a large group of individuals exposed to PBB. Methods Linear regression models were used to test the association between serum measures of thyroid function (total thyroxine (T4), total triiodothyronine (T3), free T4, free T3, thyroid stimulating hormone (TSH), and free T3: free T4 ratio) and serum PBB and PCB levels in a cross-sectional analysis of 715 participants in the Michigan PBB Registry. Results Higher PBB levels were associated with many thyroid hormones measures, including higher free T3 (p = 0.002), lower free T4 (p = 0.01), and higher free T3: free T4 ratio (p = 0.0001). Higher PCB levels were associated with higher free T4 (p = 0.0002), and higher free T3: free T4 ratio (p = 0.002). Importantly, the association between PBB and thyroid hormones was dependent on age at exposure. Among people exposed before age 16 (N = 446), higher PBB exposure was associated with higher total T3 (p = 0.01) and free T3 (p = 0.0003), lower free T4 (p = 0.04), and higher free T3: free T4 ratio (p = 0.0001). No significant associations were found among participants who were exposed after age 16. No significant associations were found between TSH and PBB or PCB in any of the analyses conducted. Conclusions This suggests that both PBB and PCB are associated with thyroid function, particularly among those who were exposed as children or prenatally. Electronic supplementary material The online version of this article (10.1186/s12940-019-0509-z) contains supplementary material, which is available to authorized users.
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- 2019
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