335 results on '"G. Hiller"'
Search Results
2. Effect of Surgical Humidification on Inflammation and Peritoneal Trauma in Colorectal Cancer Surgery: A Randomized Controlled Trial
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Shienny Sampurno, Timothy Chittleborough, Meara Dean, Michael Flood, Sandra Carpinteri, Sara Roth, Rosemary M. Millen, Helen Cain, Joseph C. H. Kong, John MacKay, Satish K. Warrier, Jacob McCormick, Jonathon G. Hiller, Alexander G. Heriot, Robert G. Ramsay, and Andrew C. Lynch
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Oncology ,Surgery - Abstract
Background Pre-clinical studies indicate that dry-cold-carbon-dioxide (DC-CO2) insufflation leads to more peritoneal damage, inflammation and hypothermia compared with humidified-warm-CO2 (HW-CO2). Peritoneum and core temperature in patients undergoing colorectal cancer (CRC) surgery were compared. Methods Sixty-six patients were randomized into laparoscopic groups; those insufflated with DC-CO2 or HW-CO2. A separate group of nineteen patients undergoing laparotomy were randomised to conventional surgery or with the insertion of a device delivering HW-CO2. Temperatures were monitored and peritoneal biopsies and bloods were taken at the start of surgery, at 1 and 3 h. Further bloods were taken depending upon hospital length-of-stay (LOS). Peritoneal samples were subjected to scanning electron microscopy to evaluate mesothelial damage. Results Laparoscopic cases experienced a temperature drop despite Bair-HuggerTM use. HW-CO2 restored normothermia (≥ 36.5 °C) by 3 h, DC-CO2 did not. LOS was shorter for colon compared with rectal cancer cases and if insufflated with HW-CO2 compared with DC-CO2; 5.0 vs 7.2 days, colon and 11.6 vs 15.4 days rectum, respectively. Unexpectedly, one third of patients had pre-existing damage. Damage increased at 1 and 3 h to a greater extent in the DC-CO2 compared with the HW-CO2 laparoscopic cohort. C-reactive protein levels were higher in open than laparoscopic cases and lower in both matched HW-CO2 groups. Conclusions This prospective RCT is in accord with animal studies while highlighting pre-existing damage in some patients. Peritoneal mesothelium protection, reduced inflammation and restoration of core-body temperature data suggest benefit with the use of HW-CO2 in patients undergoing CRC surgery.
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- 2022
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3. Chronic stress in mice remodels lymph vasculature to promote tumour cell dissemination
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Caroline P. Le, Cameron J. Nowell, Corina Kim-Fuchs, Edoardo Botteri, Jonathan G. Hiller, Hilmy Ismail, Matthew A. Pimentel, Ming G. Chai, Tara Karnezis, Nicole Rotmensz, Giuseppe Renne, Sara Gandini, Colin W. Pouton, Davide Ferrari, Andreas Möller, Steven A. Stacker, and Erica K. Sloan
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Science - Abstract
Adverse life events have been associated with reduced survival in cancer patients. Here, the authors explore the mechanism responsible and show that chronic stress in mice activates a signalling cascade in macrophages and tumour cells, which results in restructuring of the tumour lymphatic system, promoting metastasis.
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- 2016
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4. Data from Preoperative β-Blockade with Propranolol Reduces Biomarkers of Metastasis in Breast Cancer: A Phase II Randomized Trial
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Erica K. Sloan, Bernhard Riedel, Stephen Fox, Paul S. Myles, Kwok M. Ho, Sophie S. Nightingale, Michael A. Henderson, Jia-Min B. Pang, David M. Shackleford, David J. Byrne, Elizabeth M. Crone, Steven W. Cole, and Jonathan G. Hiller
- Abstract
Purpose:The majority of deaths from breast cancer occur following the development of metastatic disease, a process inhibited by β-blockers in preclinical studies. This phase II randomized controlled trial evaluated the effect of preoperative β-blockade with propranolol on biomarkers of metastatic potential and the immune cell profile within the primary tumor of patients with breast cancer.Patients and Methods:In this triple-blind placebo-controlled clinical trial, 60 patients were randomly assigned to receive an escalating dose of oral propranolol (n = 30; 80–160 mg daily) or placebo (n = 30) for 7 days prior to surgery. The primary endpoint investigated the effect of propranolol on prometastatic and proinflammatory gene expression within the primary tumor.Results:Propranolol downregulated primary tumor expression of mesenchymal genes (P = 0.002) without affecting epithelial gene expression (P = 0.21). Bioinformatic analyses implicated downregulation of Snail/Slug (P = 0.03), NF-κB/Rel (P < 0.01), and AP-1 (P < 0.01) transcription factors in structuring the observed transcriptome alterations, and identified changes in intratumoral neutrophil, natural killer cell, and dendritic cell recruitment (all P < 0.01). Patients with clinical evidence of drug response (lowered heart rate and blood pressure) demonstrated elevated tumor infiltration of CD68+ macrophages and CD8+ T cells.Conclusions:One week of β-blockade with propranolol reduced intratumoral mesenchymal polarization and promoted immune cell infiltration in early-stage surgically-resectable breast cancer. These results show that β-blockade reduces biomarkers associated with metastatic potential, and support the need for larger phase III clinical trials powered to detect the impact of β-blockade on cancer recurrence and survival.See related commentary by Blaes et al., p. 1781
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- 2023
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5. Supplementary Material from Preoperative β-Blockade with Propranolol Reduces Biomarkers of Metastasis in Breast Cancer: A Phase II Randomized Trial
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Erica K. Sloan, Bernhard Riedel, Stephen Fox, Paul S. Myles, Kwok M. Ho, Sophie S. Nightingale, Michael A. Henderson, Jia-Min B. Pang, David M. Shackleford, David J. Byrne, Elizabeth M. Crone, Steven W. Cole, and Jonathan G. Hiller
- Abstract
Supplementary Material
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- 2023
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6. Improving Cancer Survival Through Perioperative Attenuation of Adrenergic-Inflammatory Signaling
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Itay Ricon-Becker, Jonathan G. Hiller, and Shamgar Ben-Eliyahu
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- 2023
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7. Contributors
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Salahadin Abdi, Anoushka M. Afonso, Thomas A. Aloia, Gabriele Baldini, Jose Banchs, Daniel T. Baptista-Hon, Karen Basen-Engquist, Rosalind S. Bello, Shamgar Ben-Eliyahu, Celena Scheede Bergdahl, Sushma Bhatnagar, Joshua Botdorf, Christelle Botha, David L. Brown, Donal J. Buggy, Kate L. Burbury, Joseph Butler, Ronan Cahill, Franco Carli, Meghan Carton, Juan P. Cata, Cara Connolly, German Corrales, Jose Cortes, Kimberly D. Craven, John Wilson Crommett, Kristin P. Crosby, Luis Felipe Cuellar Guzman, Anahita Dabo-Trubelja, Anh Quynh Dang, Alessandro R. De Camilli, Madhavi D. Desai, Jugdeep Dhesi, Jeson R. Doctor, Jennifer S. Downs, Julia A. Dubowitz, German Echeverry, Mats Enlund, Linette Ewing, Dylan Finnerty, Joël Fokom Domgue, John Frenzel, Colleen M. Gallagher, Dorian Yarih García-Ortega, Michelle Gerstman, Arunangshu Ghoshal, Vijaya N.R. Gottumukkala, Michael P.W. Grocott, Carlos E. Guerra-Londono, Sushan Gupta, David E. Gyorki, Carin A. Hagberg, Tim G. Hales, Ernest Hawk, Alexander G. Heriot, Joseph M. Herman, Jonathan G. Hiller, Ruth E. Hubbard, Hilmy Ismail, Nelda Itzep, Emily Jasper, Saba Javed, Bhawna Jha, Shaman Jhanji, Daryl Jones, Ravish Kapoor, Faraz Khan, James S. Killinger, Samantha Koschel, Alan Kotin, Atul Prabhakar Kulkarni, Adam La Caze, Nathan Lawrentschuk, Lauren Adrienne Leddy, Celia R. Ledet, Denny Z.H. Levett, Debra Leung, Hui-Shan Lin, Alexandra L. Lewis, Daqing Ma, Kevin Madden, Anirban Maitra, Karen Colbert Maresso, Jennifer Mascarenhas, K. A. Kelly McQueen, Rodrigo Mejia, Lachlan F. Miles, Sana Mohiuddin, Daniela Molena, Tracy-Ann Moo, Karen Moody, Declan G. Murphy, Sheila Nainan Myatra, Joseph L. Nates, Jonas A. Nelson, Aisling Ní Eochagáin, Ellen O’Connor, Regina Okhuysen-Cawley, Pascal Owusu-Agyemang, Gouri H. Pantvaidya, Pamela C. Papadopoulos, Marie-Odile Parat, Judith Partridge, Sephalie Patel, Vikram B. Patel, Nicholas Perry, Thais O. Polanco, Shannon M. Popovich, George Poulogiannis, Perez-Gonzalez Oscar Rafael, Sanketh Rampes, Krithika S. Rao, Sally Radelat Raty, Shehla Razvi, Natasha Reid, Itay Ricon-Becker, Bernhard J. Riedel, Emily B. Roarty, Maria Alma Rodriguez, Suzanne Russo, Iqira Saeed, Sunil K. Sahai, Naveen Salins, Niranjan Sathianathen, Shveta Seth, Paul N. Shaw, Aislinn Sherwin, Sanjay Shete, Qiuling Shi, Conor Shields, Jo-Lynn Tan, Hanae K. Tokita, Tom Wall, Ronald S. Walters, Xin Shelley Wang, Phil Ward, Anna Louise Waylen, Laurence Weinberg, Matthias Wilhelm Wichmann, Timothy Wigmore, Syed Wamique Yusuf, Wafik Zaky, and Gang Zheng
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- 2023
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8. Anesthetic technique and cancer surgery outcomes
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Bernhard Riedel, Jonathan G. Hiller, and Julia Dubowitz
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medicine.medical_specialty ,Surgical stress ,business.industry ,Cancer ,Perioperative ,medicine.disease ,Minimal residual disease ,law.invention ,Metastasis ,03 medical and health sciences ,0302 clinical medicine ,Anesthesiology and Pain Medicine ,Randomized controlled trial ,030202 anesthesiology ,law ,030220 oncology & carcinogenesis ,Anesthetic ,medicine ,Intensive care medicine ,Prospective cohort study ,business ,medicine.drug - Abstract
Purpose of review Surgery remains integral to treating solid cancers. However, the surgical stress response, characterized by physiologic perturbation of the adrenergic, inflammatory, and immune systems, may promote procancerous pathways. Anesthetic technique per se may attenuate/enhance these pathways and thereby could be implicated in long-term cancer outcomes. Recent findings To date, clinical studies have predominantly been retrospective and underpowered and, thus limit meaningful conclusions. More recently, prospective studies of regional anesthesia for breast and colorectal cancer surgery have failed to demonstrate long-term cancer outcome benefit. However, based on the consistent observation of protumorigenic effects of surgical stress and that of volatile anesthesia in preclinical studies, supported by in vivo models of tumor progression and metastasis, we await robust prospective clinical studies exploring the role of propofol-based total intravenous anesthesia (cf. inhalational volatiles). Additionally, anti-adrenergic/anti-inflammatory adjuncts, such as lidocaine, nonsteroidal anti-inflammatory drugs and the anti-adrenergic propranolol warrant ongoing research. Summary The biologic perturbation of the perioperative period, compounded by the effects of anesthetic agents, renders patients with cancer particularly vulnerable to enhanced viability of minimal residual disease, with long-term outcome consequences. However, low level and often conflicting clinical evidence equipoise currently exists with regards to optimal oncoanesthesia techniques. Large, prospective, randomized control trials are urgently needed to inform evidence-based clinical practice guidelines.
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- 2021
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9. ASO Visual Abstract: Effect of Surgical Humidification on Inflammation and Peritoneal Trauma in Colorectal Cancer Surgery-A Randomised Controlled Trial
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Shienny Sampurno, Timothy Chittleborough, Meara Dean, Michael Flood, Sandra Carpinteri, Sara Roth, Rosemary M. Millen, Helen Cain, Joseph C. H. Kong, John MacKay, Satish K. Warrier, Jacob McCormick, Jonathon G. Hiller, Alexander G. Heriot, Robert G. Ramsay, and Andrew C. Lynch
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Inflammation ,Oncology ,Humans ,Surgery ,Cytoreduction Surgical Procedures ,Peritoneum ,Colorectal Neoplasms ,Digestive System Surgical Procedures ,Peritoneal Neoplasms - Published
- 2022
10. Dynamics of Delay-Coupled Excitable Neural Systems.
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Markus A. Dahlem, G. Hiller, Anastasiia Panchuk, and Eckehard Schöll
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- 2009
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11. Molecular Structures Reveal the Origin of Spectral Variation in Cryptophyte Light Harvesting Antenna Proteins
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Katharine A. Michie, Stephen J. Harrop, Harry W. Rathbone, Krystyna E. Wilk, Chang Ying Teng, Kerstin Hoef‐Emden, Roger G. Hiller, Beverley R. Green, and Paul M. G. Curmi
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History ,Polymers and Plastics ,Business and International Management ,Molecular Biology ,Biochemistry ,Industrial and Manufacturing Engineering - Published
- 2022
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12. Why We Serve: Native Americans in the United States Armed Forces by Alexandra N. Harris and Mark G. Hirsch
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Joseph G. Hiller
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- 2022
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13. Modes of carbon dioxide delivery during laparoscopy generate distinct differences in peritoneal damage and hypoxia in a porcine model
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Robert G. Ramsay, Timothy J. Chittleborough, Alexander G. Heriot, A. C. Lynch, Shienny Sampurno, Jonathan G. Hiller, and Sandra Carpinteri
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Insufflation ,Swine ,Epithelium ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,Peritoneum ,medicine ,Animals ,Hypoxia ,Laparoscopy ,Microvilli ,medicine.diagnostic_test ,business.industry ,Carbon Dioxide ,Hypoxia (medical) ,medicine.anatomical_structure ,chemistry ,030220 oncology & carcinogenesis ,Anesthesia ,Carbon dioxide ,Immunohistochemistry ,Female ,030211 gastroenterology & hepatology ,Surgery ,medicine.symptom ,business ,Mesothelial Cell ,Abdominal surgery - Abstract
Insufflation with CO2 can employ continuous flow, recirculated gas and/or additional warming and humidification. The ability to compare these modes of delivery depends upon the assays employed and opportunities to minimize subject variation. The use of pigs to train colorectal surgeons provided an opportunity to compare three modes of CO2 delivery under controlled circumstances. Sixteen pigs were subjected to rectal resection, insufflated with dry-cold CO2 (DC-CO2) (n = 5), recirculated CO2 by an AirSeal device (n = 5) and humidification and warming (HW-CO2) by a HumiGard device (n = 6). Peritoneal biopsies were harvested from the same region of the peritoneum for fixation for immunohistochemistry for hypoxia-inducible factor 1 alpha (HIF-1α) and scanning electron microscopy (SEM) to evaluate hypoxia induction or tissue/cellular damage, respectively. DC-CO2 insufflation by both modes leads to significant damage to mesothelial cells as measured by cellular bulging and retraction as well as microvillus shortening compared with HW-CO2 at 1 to 1.5 h. DC-CO2 also leads to a rapid and significant induction of HIF-1α compared with HW-CO2. DC-CO2 insufflation induces substantive cellular damage and hypoxia responses within the first hour of application. The use of HW-CO2 insufflation ameliorates these processes for the first one to one and half hours in a large mammal used to replicate surgery in humans.
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- 2019
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14. Consistent Model of Ultrafast Energy Transfer in Peridinin Chlorophyll-a Protein Using Two-Dimensional Electronic Spectroscopy and Förster Theory
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Chanelle C. Jumper, Roger G. Hiller, Gregory D. Scholes, Mary H. deGolian, and Zi S. D. Toa
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Physics ,Physics::Biological Physics ,education.field_of_study ,010304 chemical physics ,Population ,Chromophore ,Conical intersection ,010402 general chemistry ,01 natural sciences ,Electron spectroscopy ,Spectral line ,0104 chemical sciences ,Surfaces, Coatings and Films ,chemistry.chemical_compound ,Peridinin ,chemistry ,Chemical physics ,0103 physical sciences ,Materials Chemistry ,Physical and Theoretical Chemistry ,education ,Absorption (electromagnetic radiation) ,Excitation - Abstract
Solar light harvesting begins with electronic energy transfer in structurally complex light-harvesting antennae such as the peridinin chlorophyll-a protein from dinoflagellate algae. Peridinin chlorophyll-a protein is composed of a unique combination of chlorophylls sensitized by carotenoids in a 4:1 ratio, and ultrafast spectroscopic methods have previously been utilized in elucidating their energy-transfer pathways and timescales. However, due to overlapping signals from various chromophores and competing pathways and timescales, a consistent model of intraprotein electronic energy transfer has been elusive. Here, we used a broad-band two-dimensional electronic spectroscopy, which alleviates the spectral congestion by dispersing excitation and detection wavelengths. Interchromophoric couplings appeared as cross peaks in two-dimensional electronic spectra, and these spectral features were observed between the peridinin S2 states and chlorophyll-a Qx and Qy states. In addition, the inherently high time and frequency resolutions of two-dimensional electronic spectroscopy enabled accurate determination of the ultrafast energy-transfer dynamics. Kinetic analysis near the peridinin S1 excited-state absorption, which forms in 24 fs after optical excitation, reveals an ultrafast energy-transfer pathway from the peridinin S2 state to the chlorophyll-a Qx state, a hitherto unconfirmed pathway critical for fast interchromophoric transfer. We propose a model of ultrafast peridinin chlorophyll-a protein photophysics that includes (1) a conical intersection between peridinin S2 and S1 states to explain both the ultrafast peridinin S1 formation and the residual peridinin S2 population for energy transfer to chlorophyll-a, and (2) computationally and experimentally derived peridinin S2 site energies that support the observed ultrafast peridinin S2 to chlorophyll-a Qx energy transfer.
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- 2019
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15. A Survey About Fever Knowledge, Attitudes, and Practices Among Parents
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Matthew G Hiller, Michael S Caffery, and Rodolfo E. Bégué
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Adult ,Male ,Parents ,Health Knowledge, Attitudes, Practice ,medicine.medical_specialty ,Antipyretics ,Fever ,Thermometers ,media_common.quotation_subject ,Positive perception ,030226 pharmacology & pharmacy ,03 medical and health sciences ,0302 clinical medicine ,Surveys and Questionnaires ,030225 pediatrics ,Perception ,medicine ,Humans ,Negative perception ,Child ,Confusion ,media_common ,business.industry ,Infant ,Louisiana ,Child, Preschool ,Family medicine ,Pediatrics, Perinatology and Child Health ,Female ,medicine.symptom ,business - Abstract
A 21-question survey was conducted among parents attending 4 pediatric outpatient practices to assess their knowledge, perceptions, and attitudes about fever. One hundred and ninety-seven surveys were included. Most commonly the participating parent was the mother. Parents used mainly axillary thermometers to measure child’s temperature and mentioned integers for their definition of fever, 100°F being the most frequent answer. Most parents would treat all fevers and would use alternating antipyretics. Parents had a generally negative perception of fever: only one third thought fever may have some benefit, and more than half thought there must be some risk. A positive perception of fever was associated with parental educational level but not with information by the pediatrician. There is much confusion about fever among our parents, a negative perception is prevalent, and parents seem to receive—or recall—little information from the pediatrician.
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- 2019
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16. Anesthetic technique and cancer outcomes: a meta-analysis of total intravenous versus volatile anesthesia
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Bernhard Riedel, Maria A. Lopez-Olivo, Andrea Yap, Julia Dubowitz, and Jonathan G. Hiller
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medicine.medical_specialty ,Cellular immunity ,business.industry ,Hazard ratio ,Cancer ,General Medicine ,medicine.disease ,Newcastle–Ottawa scale ,03 medical and health sciences ,0302 clinical medicine ,Anesthesiology and Pain Medicine ,030202 anesthesiology ,030220 oncology & carcinogenesis ,Anesthesia ,Meta-analysis ,Anesthesiology ,Anesthetic ,Medicine ,business ,Survival rate ,medicine.drug - Abstract
Cancer-related mortality, a leading cause of death worldwide, is often the result of metastatic disease recurrence. Anesthetic techniques have varying effects on innate and cellular immunity, activation of adrenergic-inflammatory pathways, and activation of cancer-promoting cellular signaling pathways; these effects may translate into an influence of anesthetic technique on long-term cancer outcomes. To further analyze the effects of propofol (intravenous) and volatile (inhalational gas) anesthesia on cancer recurrence and survival, we undertook a systematic review with meta-analysis. Databases were searched up to 14 November 2018. Comparative studies examining the effect of inhalational volatile anesthesia and propofol-based total intravenous anesthesia (TIVA) on cancer outcomes were included. The Newcastle Ottawa Scale (NOS) was used to assess methodological quality and bias. Reported hazard ratios (HRs) were pooled and 95% confidence intervals (CIs) calculated. Ten studies were included; six studies examined the effect of anesthetic agent type on recurrence-free survival following breast, esophageal, and non-small cell lung cancer (n = 7,866). The use of TIVA was associated with improved recurrence-free survival in all cancer types (pooled HR, 0.78; 95% CI, 0.65 to 0.94; P < 0.01). Eight studies (n = 18,778) explored the effect of anesthetic agent type on overall survival, with TIVA use associated with improved overall survival (pooled HR, 0.76; 95% CI, 0.63 to 0.92; P < 0.01). This meta-analysis suggests that propofol-TIVA use may be associated with improved recurrence-free survival and overall survival in patients having cancer surgery. This is especially evident where major cancer surgery was undertaken. Nevertheless, given the inherent limitations of studies included in this meta-analysis these findings necessitate prospective randomized trials to guide clinical practice. PROSPERO (CRD42018081478); registered 8 October, 2018.
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- 2019
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17. The Story of Judith and the Triumph of the Oppressed : A Deep Dive Into the Narrative, Theology, and Impact of a Biblical Icon
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Wanda G. Hiller and Wanda G. Hiller
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In an era where resilience and faith were essential for survival, Judith's story shines as a beacon of courage and spiritual triumph. Revered as a powerful heroine in the Apocryphal texts, Judith defies not only an oppressor's might but also the societal constraints of her time, emerging as a symbol of hope and strength. In The Story of Judith and the Triumph of the Oppressed, Wanda G. Hiller meticulously explores the layers of narrative and theology that have immortalized Judith as a cultural and religious icon. With a focus on the historical and socio-political context that shaped this story, Hiller brings to light the timeless themes of justice, faith, and divine intervention that resonate across generations. This scholarly yet accessible analysis sheds new light on Judith's role in shaping Jewish identity and her profound influence on both Jewish and Christian traditions.
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- 2024
18. Samuel Daniel’s Debt to Stefano Guazzo
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Geoffrey G. Hiller
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Linguistics and Language ,History ,Literature and Literary Theory ,Debt ,media_common.quotation_subject ,Political economy ,Economic history ,Library and Information Sciences ,Language and Linguistics ,media_common - Published
- 2017
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19. Unveiling the excited state energy transfer pathways in peridinin-chlorophyll a- protein by ultrafast multi-pulse transient absorption spectroscopy
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Donatas Zigmantas, Vladislava Voiciuk, Kipras Redeckas, Roger G. Hiller, and Mikas Vengris
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Chlorophyll ,Chlorophyll a ,Biophysics ,02 engineering and technology ,010402 general chemistry ,Photochemistry ,01 natural sciences ,Biochemistry ,chemistry.chemical_compound ,Energy flow ,Ultrafast laser spectroscopy ,Spectroscopy ,Chemistry ,Chlorophyll A ,Spectrum Analysis ,Cell Biology ,021001 nanoscience & nanotechnology ,Carotenoids ,0104 chemical sciences ,Kinetics ,Peridinin ,Energy Transfer ,Chemical physics ,Intramolecular force ,Excited state ,0210 nano-technology ,Ultrashort pulse - Abstract
Time-resolved multi-pulse methods were applied to investigate the excited state dynamics, the interstate couplings, and the excited state energy transfer pathways between the light-harvesting pigments in peridinin-chlorophyll a-protein (PCP). The utilized pump-dump-probe techniques are based on perturbation of the regular PCP energy transfer pathway. The PCP complexes were initially excited with an ultrashort pulse, resonant to the S0 → S2 transition of the carotenoid peridinin. A portion of the peridinin-based emissive intramolecular charge transfer (ICT) state was then depopulated by applying an ultrashort NIR pulse that perturbed the interaction between S1 and ICT states and the energy flow from the carotenoids to the chlorophylls. The presented data indicate that the peridinin S1 and ICT states are spectrally distinct and coexist in an excited state equilibrium in the PCP complex. Moreover, numeric analysis of the experimental data asserts ICT → Chl-a as the main energy transfer pathway in the photoexcited PCP systems.
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- 2017
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20. A comparative study of bone biopsies from the iliac crest, the tibial bone, and the lumbar spine
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Jan T. Kielstein, Ruth G. G. Hiller, Janin Reifenrath, Margret Patecki, Claudia Neunaber, and Heike Kielstein
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Male ,0301 basic medicine ,medicine.medical_specialty ,Trabecular bone volume ,Bone density ,Biopsy ,Osteoporosis ,030209 endocrinology & metabolism ,Lumbar vertebrae ,lcsh:RC870-923 ,Sensitivity and Specificity ,Iliac crest ,Ilium ,03 medical and health sciences ,0302 clinical medicine ,Cadaver ,Humans ,Medicine ,Renal osteodystrophy ,Tibia ,Aged ,Bone biopsy ,Lumbar Vertebrae ,medicine.diagnostic_test ,business.industry ,Reproducibility of Results ,Organ Size ,Middle Aged ,medicine.disease ,lcsh:Diseases of the genitourinary system. Urology ,030104 developmental biology ,medicine.anatomical_structure ,Nephrology ,Female ,Radiology ,business ,Research Article - Abstract
Background Patients with an impaired renal function show a high incidence of bone and mineral disturbances. These ‘chronic kidney disease – mineral and bone disorders’ (CKD-MBD) range from high turnover osteoporosis to adynamic bone disease. Currently, the histomorphometric analysis of a bone biopsy taken from the iliac crest is viewed as the gold standard for CKD-MBD subtype differentiation. However, the clinical relevance of such a biopsy is questionable since iliac crest fractures are an extremely rare finding. Therefore, we aimed to elucidate if the histomorphometric parameter ‘trabecular bone volume (BV/TV)’ from the iliac crest is representative for other biopsy locations. We chose two skeletal sites of higher fracture risk for testing, namely, the tibial bone and the lumbar spine, to examine if the current gold standard of bone biopsy is indeed golden. Methods Bone biopsies were taken from 12 embalmed body donors at the iliac crest, the proximal tibia, and the lumbar vertebral body, respectively. Masson-Goldner stained sections of methyl methacrylate embedded biopsies were used for trabecular bone volume calculation. Furthermore, exemplary μ-computed tomography (XtremeCT) scans with subsequent analysis were performed. Results Median values of trabecular bone volume were comparable between all body donors with median (interquartile range, IQR) 18.3% (10.9–22.9%) at the iliac crest, 21.5% (9.5–40.1%) at the proximal tibia, and 16.3% (11.4–25.0%) at the lumbar spine. However, single values showed extensive intra-individual variation, which were also confirmed by XtremeCT imaging. Conclusions Distinct intra-individual heterogeneity of trabecular bone volume elucidate why a bone biopsy from one site does not necessarily predict patient relevant endpoints like hip or spine fractures. Physicians interpreting bone biopsy results should know this limitation of the current gold standard for CKD-MBD diagnostic, especially, when systemic therapeutic decisions should be based on it.
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- 2017
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21. Preoperative β-Blockade with Propranolol Reduces Biomarkers of Metastasis in Breast Cancer: A Phase II Randomized Trial
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Michael A. Henderson, Erica K. Sloan, Steven W. Cole, Bernhard Riedel, Stephen B. Fox, Sophie Nightingale, David J Byrne, David M. Shackleford, Jonathan G. Hiller, Paul S. Myles, Kwok M. Ho, Elizabeth M. Crone, and Jia Min B. Pang
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0301 basic medicine ,Oncology ,Cancer Research ,medicine.medical_specialty ,Phases of clinical research ,Breast Neoplasms ,Propranolol ,CD8-Positive T-Lymphocytes ,law.invention ,Metastasis ,03 medical and health sciences ,0302 clinical medicine ,Breast cancer ,Randomized controlled trial ,law ,Internal medicine ,Clinical endpoint ,Medicine ,Humans ,business.industry ,medicine.disease ,Primary tumor ,Clinical trial ,030104 developmental biology ,030220 oncology & carcinogenesis ,Neoplasm Recurrence, Local ,business ,Biomarkers ,medicine.drug - Abstract
Purpose: The majority of deaths from breast cancer occur following the development of metastatic disease, a process inhibited by β-blockers in preclinical studies. This phase II randomized controlled trial evaluated the effect of preoperative β-blockade with propranolol on biomarkers of metastatic potential and the immune cell profile within the primary tumor of patients with breast cancer. Patients and Methods: In this triple-blind placebo-controlled clinical trial, 60 patients were randomly assigned to receive an escalating dose of oral propranolol (n = 30; 80–160 mg daily) or placebo (n = 30) for 7 days prior to surgery. The primary endpoint investigated the effect of propranolol on prometastatic and proinflammatory gene expression within the primary tumor. Results: Propranolol downregulated primary tumor expression of mesenchymal genes (P = 0.002) without affecting epithelial gene expression (P = 0.21). Bioinformatic analyses implicated downregulation of Snail/Slug (P = 0.03), NF-κB/Rel (P < 0.01), and AP-1 (P < 0.01) transcription factors in structuring the observed transcriptome alterations, and identified changes in intratumoral neutrophil, natural killer cell, and dendritic cell recruitment (all P < 0.01). Patients with clinical evidence of drug response (lowered heart rate and blood pressure) demonstrated elevated tumor infiltration of CD68+ macrophages and CD8+ T cells. Conclusions: One week of β-blockade with propranolol reduced intratumoral mesenchymal polarization and promoted immune cell infiltration in early-stage surgically-resectable breast cancer. These results show that β-blockade reduces biomarkers associated with metastatic potential, and support the need for larger phase III clinical trials powered to detect the impact of β-blockade on cancer recurrence and survival. See related commentary by Blaes et al., p. 1781
- Published
- 2019
22. Consistent Model of Ultrafast Energy Transfer in Peridinin Chlorophyll
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Zi S D, Toa, Mary H, deGolian, Chanelle C, Jumper, Roger G, Hiller, and Gregory D, Scholes
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Kinetics ,Energy Transfer ,Models, Chemical ,Chlorophyll A ,Spectrum Analysis ,Dinoflagellida ,Thermodynamics ,Carotenoids - Abstract
Solar light harvesting begins with electronic energy transfer in structurally complex light-harvesting antennae such as the peridinin chlorophyll
- Published
- 2019
23. Efecto terapéutico del alprostadil en pacientes con isquemia crítica terminal de los miembros inferiores
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Alfredo J. Karles-Ernotte, Aníbal Bermúdez-Posada, Andrea T. Padilla-Castro, Héctor M. Rincón-Sánchez, Heinz G. Hiller-Correa, Mauricio Novoa-Leal, and Katherine Drews-Elger
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Peripheral artery disease ,030204 cardiovascular system & hematology ,Prostaglandinas ,Isquemia ,03 medical and health sciences ,0302 clinical medicine ,Reperfusión ,Ischemia ,RC666-701 ,Reperfusion ,Prostaglandins ,Diseases of the circulatory (Cardiovascular) system ,030212 general & internal medicine ,Cardiology and Cardiovascular Medicine ,Enfermedad arterial periférica - Abstract
ResumenObjetivoEl manejo de la isquemia crítica de los miembros inferiores representa un reto para el cirujano vascular debido a la alta tasa de amputaciones y mortalidad. Las opciones de manejo actuales: puente femorodistal, angioplastia con o sin la colocación de Stents y la resección de la placa con láser o de manera mecánica, presentan a largo plazo una tasa de éxito muy baja y un número de amputaciones supracondíleas que continúa siendo elevado.MétodosPara este estudio prospectivo se reclutaron 173 pacientes con diagnóstico de estadio avanzado, con isquemia crítica de miembro inferior quienes fueron tratados con alprostadil (60 – 120 mcgr/día) por vía intravenosa sistémica por 28 días. La respuesta se midió clínicamente por mejoría del llenado capilar y con el uso de la escala análoga visual del dolor.ResultadosAl momento del alta hospitalaria el 94.3% de los pacientes mejoró el puntaje en la escala análoga visual del dolor (p < 0.0001). El seguimiento a más de un año del tratamiento con alprostadil mostró que el 97% de los pacientes mejoró significativamente su estadio de isquemia, evitándose así una amputación mayor. No se observó respuesta al tratamiento en pacientes previamente intervenidos por vía endovascular (5 pacientes).ConclusionesEl tratamiento de pacientes con isquemia crítica de miembro inferior con alpostadil por infusión intravenosa, con bolos diarios de entre 60 y 120 mcg durante 28 días, este medicamento es seguro y presenta mínimos efectos secundarios. Esta terapia mejora sustancialmente el estadio funcional de Rutherford en estos pacientes y evita amputaciones mayores.AbstractObjetiveManagement of critical lower limb ischemia represents a challenge for the vascular surgeon due to the high rate of amputations and mortality. Current management options include femorodistal bypass, angioplasty with or without stent and laser or mechanical resection of the plaque. They present a low success rate in the long run and a number of supracondylar amputations that still remains high.MethodsThis prospective study included 173 patients diagnosed with advanced stage critical lower limb ischemia who were treated with systemic intravenous alprostadil (60 - 120 mcg/day) during 8 days. Response was measured clinically with improvement of capillary refill and using the visual analog scale for pain.ResultsUpon discharge 94.3% of patients improved their visual analogue scale score for pain (p < 0.0001). Follow-up for more than a year of alprostadil treatment revealed that 97% of patients significantly improved their ischemia status, thus avoiding further amputation. No response to treatment was observed in patients who had previously undergone endovascular surgery (5 patients).ConclusionsTreating patients with critical lower limb ischemia with intravenous alprostadil, administering daily doses of between 60 and 120 mcg during 28 days shows that this drug is safe and causes minimal secondary effects. This therapy significantly improves Rutherford's function state in these patients and avoids further amputations.
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- 2017
24. Mechanistic Interplay between Light Switching and Guest Binding in Photochromic [Pd
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Ru-Jin, Li, Julian J, Holstein, Wolf G, Hiller, Joakim, Andréasson, and Guido H, Clever
- Abstract
Photochromic [Pd
- Published
- 2019
25. Period 3: London—New Riches, New Squalor (1781–1870)
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Peter L. Groves, Geoffrey G. Hiller, and Alan F. Dilnot
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education.field_of_study ,History ,White (horse) ,media_common.quotation_subject ,Judaism ,Immigration ,Population ,Toleration ,Politics ,Moors ,Economic history ,education ,Industrial Revolution ,media_common - Abstract
This introduction considers the alarming growth in extent and population of London in the Industrial Revolution and its social consequences, an increase not just in size but in diversity, thanks to the arrival of immigrants drawn by Britain’s religious toleration, its political liberties and its economic opportunities. Jewish immigrants from Eastern Europe, for example, were beginning late in the eighteenth century to supplement those who had come earlier from Western Europe. Among the crowds Wordsworth observes on the streets of London in the 1790s are not just “The Frenchman and the Spaniard,” or even “The Swede, the Russian”, but also American Indians, “Moors, / Malays, Lascars, the Tartar and Chinese, / And Negro Ladies in white muslin gowns” (The Prelude 1805, 7.235–43). The introduction looks at the railways, and their enablement of suburbanisation, and at the beginnings of social and political reform, including the expanding base of education and the consequent creation of a broad reading public.
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- 2019
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26. Period 1: London—Birth of a New Order (1558–1659)
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Alan F. Dilnot, Geoffrey G. Hiller, and Peter L. Groves
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medicine.anatomical_structure ,History ,medicine ,Globe ,Ancient history ,The Imaginary ,Period (music) ,Accession ,Order (virtue) ,Bridge (music) ,Queen (playing card) - Abstract
This Introduction looks at the growth of London and Westminster from the accession of Queen Elizabeth I (when it was already a busy port and a diverse and cosmopolitan city) to the Restoration of Charles II. It pays particular attention to the lay-out of Elizabethan London, and follows in detail an imaginary time-traveller on her journey from Bedlam, north of the City, down Bishopsgate, southwards past the Royal Exchange and Lombard St, and over London Bridge to Shakespeare’s Globe, with some consequent consideration of Elizabethan theatre.
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- 2019
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27. Period 4: London—Capital of Empire, 1871–1914
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Alan F. Dilnot, Geoffrey G. Hiller, and Peter L. Groves
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New Woman ,media_common.quotation_subject ,Suffrage ,Globe ,Empire ,Quarter (United States coin) ,Periodical literature ,Diamond jubilee ,medicine.anatomical_structure ,Capital (economics) ,Political science ,Economic history ,medicine ,media_common - Abstract
This introduction develops the theme of London’s rapid expansion and transformation into a modern city, with improved transportation by Underground Railway, electric trams and the omnibus, and unimaginably fast communication via the telegraph and (later) the telephone. It considers the dissemination of literature through the development of periodical publication and the ‘railway novel’, and the rise of free public libraries established through the Public Libraries Act of 1850. The introduction also contemplates London’s morally ambivalent role as the capital of an empire covering a quarter of the globe (as highlighted by the Diamond Jubilee of 1897), and social developments such as the ‘scandalous’ rise of the ‘New Woman’ and the struggle for female suffrage.
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- 2019
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28. Period 2: London in the Enlightenment (1660–1780)
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Alan F. Dilnot, Peter L. Groves, and Geoffrey G. Hiller
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History ,Punishment ,media_common.quotation_subject ,Enlightenment ,Legislature ,Capitalism ,Plague (disease) ,language.human_language ,Georgian ,Capital (economics) ,language ,Economic history ,Stock market ,media_common - Abstract
This Introduction, dealing inevitably with the Restoration, the Great Plague and the Great Fire (and the subsequent rebuilding of the City), considers this period as the beginning of the transformation of London into the great commercial, financial and imperial capital it became in the nineteenth century, with the development of great public buildings like new St Paul’s Cathedral and the rebuilt Royal Exchange, the establishment of broad thoroughfares, public parks and fashionable districts such as Mayfair, and the foundation of the Royal Society and (later) the British Museum. It was the new Royal Exchange and the unprecedented founding of the Bank of England that marked the emergence of London as the hub of global capitalism that it still is, generating a flood of money into the economy that seemed to some contemporaries to be a channel of moral corruption, as exemplified by the South Sea Bubble, an early manifestation of what has recently been termed “irrational exuberance” in the stock market. It is no coincidence that this period saw a rapid growth in legislative concern with crimes of property, and the introduction ends with a consideration of crime and punishment in Georgian London, and its somewhat ambivalent treatment in the literature of the time.
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- 2019
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29. In reply: Comment on 'Anesthetic technique and cancer outcomes: a meta-analysis of total intravenous versus volatile anesthesia'
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Bernhard Riedel, Andrea Yap, Julia Dubowitz, Maria A. Lopez-Olivo, and Jonathan G. Hiller
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medicine.medical_specialty ,business.industry ,Pain medicine ,MEDLINE ,Cancer ,General Medicine ,medicine.disease ,Anesthesiology and Pain Medicine ,Neoplasms ,Anesthesia ,Meta-analysis ,Anesthesiology ,Anesthetic ,Anesthesia, Intravenous ,medicine ,Humans ,business ,Anesthetics ,medicine.drug - Published
- 2019
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30. Correction to: Anesthetic technique and cancer outcomes: a meta-analysis of total intravenous versus volatile anesthesia
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Julia Dubowitz, Maria A. Lopez-Olivo, Jonathan G. Hiller, Andrea Yap, and Bernhard Riedel
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medicine.medical_specialty ,business.industry ,Hazard ratio ,Cancer ,General Medicine ,medicine.disease ,Confidence interval ,03 medical and health sciences ,0302 clinical medicine ,Anesthesiology and Pain Medicine ,030202 anesthesiology ,030220 oncology & carcinogenesis ,Anesthesia ,Anesthesiology ,Meta-analysis ,Anesthetic ,Medicine ,business ,Survival analysis ,medicine.drug - Abstract
There was an isolated error relating to the Oh et al. study (1) within our recurrence-free survival analysis. When the reported estimates for Oh et al. are corrected, the pooled hazard ratio (HR) is now 0.87; 95% confidence interval (CI), 0.66 to 1.15; P=0.32.
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- 2019
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31. A Primer: Extension, Indian Land Tenure, and Rangeland Limitations
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Joseph P. Brewer, Joseph G. Hiller, Shawn Burke, and Trent Teegerstrom
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Economic growth ,Resource (biology) ,Geography, Planning and Development ,Management, Monitoring, Policy and Law ,01 natural sciences ,Indian country ,0103 physical sciences ,Development economics ,Natural resource management ,Federally Recognized Tribal Extension Program (FRTEP) ,Land tenure ,0505 law ,Cooperative Extension ,010302 applied physics ,050502 law ,Ecology ,business.industry ,05 social sciences ,Indian Country Extension ,Indian Land Tenure ,Natural resource ,rangelands ,Geography ,Agriculture ,American Indian ,Rangeland ,business - Abstract
On the Ground•Rangelands in Indian Country are unique. Legal and historical realities present challenges to range and natural resources management not seen outside of Indian Country.•Cooperative Extension educational programs are highly valued for their important impact on Agriculture and Natural Resources in counties. These programs exist on less then 10% of America’s Indian Reservations. Federally Recognized Tribal Extension Program (FRTEP) personnel, in the few places where they are funded, are a sought after resource to tribal individuals and communities in Indian Country.
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- 2016
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32. The Role of Perioperative Pharmacological Adjuncts in Cancer Outcomes: Beta-Adrenergic Receptor Antagonists, NSAIDs and Anti-fibrinolytics
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Marie-Odile Parat, Shamgar Ben-Eliyahu, and Jonathan G. Hiller
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medicine.medical_specialty ,Surgical stress ,Adrenergic receptor ,business.industry ,medicine.medical_treatment ,Cancer ,Immunosuppression ,Perioperative ,Propranolol ,medicine.disease ,Bioinformatics ,Anesthesiology and Pain Medicine ,Anesthesiology ,Anesthesia ,Celecoxib ,medicine ,business ,medicine.drug - Abstract
The perioperative period of cancer surgery and its impact on patients’ long-term cancer outcomes is of increasing research interest. The physiological changes coincident with surgery are characterized by a stress response manifesting as activation of inflammatory pathways and immunosuppression. These changes are potentially deleterious to a patient’s capacity to control residual or released tumor cells. Of particular relevance to anesthesiologists is the role of available adjuncts that may offset these changes to improve patients' recovery from surgery and their long-term cancer outcomes. Animal and human evidence indicates a potential therapeutic benefit for β-adrenergic receptor antagonists, selective cyclooxygenase inhibitors, and anti-fibrinolytics administered through the perioperative period. In addition to reducing the surgical stress response, these agents may effect the cancer-host tissue interface to reduce cancer invasion and dissemination. Future research will focus on defining the role of these agents as integral perioperative adjuncts for cancer surgery.
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- 2015
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33. Neuraxial Anesthesia Reduces Lymphatic Flow
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Shakher Ramdave, Jonathan G. Hiller, Kailash Narayan, Michael S Hofman, Bernhard Riedel, and Hilmy Ismail
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Male ,medicine.medical_specialty ,medicine.medical_treatment ,Deep vein ,Brachytherapy ,Anesthesia, Spinal ,03 medical and health sciences ,0302 clinical medicine ,030202 anesthesiology ,Anesthesiology ,medicine ,Humans ,business.industry ,Middle Aged ,Lymphatic flow ,medicine.disease ,Thrombosis ,Surgery ,body regions ,Anesthesiology and Pain Medicine ,Lymphatic system ,medicine.anatomical_structure ,Lower Extremity ,Sympathectomy ,Anesthesia ,Female ,Lymph ,business ,Lymphoscintigraphy ,030217 neurology & neurosurgery - Abstract
Dilation of lymphatic vessels may contribute to iatrogenic dissemination of cancer cells during surgery. We sought to determine whether neuraxial anesthesia reduces regional lymphatic flow. Using nuclear lymphoscintigraphy, 5 participants receiving spinal anesthesia for brachytherapy had lower extremity lymph flow at rest compared with flow under conditions of spinal anesthesia. Six limbs were analyzed. Four limbs were excluded because of failure to demonstrate lymph flow (1 patient, 2 limbs), colloid injection error (1 limb), and undiagnosed deep vein thrombosis (1 limb). All analyzed limbs showed reduced lymph flow washout from the pedal injection site (range 62%-100%) due to neuraxial anesthesia. Lymph flow was abolished in 3 limbs. We report proof-of-concept that neuraxial anesthesia reduces lymphatic flow through a likely mechanism of sympathectomy.
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- 2016
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34. Perioperative events influence cancer recurrence risk after surgery
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Jonathan G. Hiller, Bernhard Riedel, Nicholas J. S. Perry, George Poulogiannis, and Erica K. Sloan
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medicine.medical_specialty ,Adrenergic Antagonists ,Surgical stress ,Neoplasm, Residual ,medicine.medical_treatment ,Anti-Inflammatory Agents ,Disease ,Perioperative Care ,03 medical and health sciences ,0302 clinical medicine ,Fibrinolytic Agents ,030202 anesthesiology ,Neoplasms ,medicine ,Risk of mortality ,Humans ,Neoplasm Metastasis ,Neoadjuvant therapy ,business.industry ,Cancer ,Perioperative ,medicine.disease ,Minimal residual disease ,Neoadjuvant Therapy ,Surgery ,Oncology ,030220 oncology & carcinogenesis ,Disease Progression ,Neoplasm Recurrence, Local ,business ,Fibrinolytic agent - Abstract
Surgery is a mainstay treatment for patients with solid tumours. However, despite surgical resection with a curative intent and numerous advances in the effectiveness of (neo)adjuvant therapies, metastatic disease remains common and carries a high risk of mortality. The biological perturbations that accompany the surgical stress response and the pharmacological effects of anaesthetic drugs, paradoxically, might also promote disease recurrence or the progression of metastatic disease. When cancer cells persist after surgery, either locally or at undiagnosed distant sites, neuroendocrine, immune, and metabolic pathways activated in response to surgery and/or anaesthesia might promote their survival and proliferation. A consequence of this effect is that minimal residual disease might then escape equilibrium and progress to metastatic disease. Herein, we discuss the most promising proposals for the refinement of perioperative care that might address these challenges. We outline the rationale and early evidence for the adaptation of anaesthetic techniques and the strategic use of anti-adrenergic, anti-inflammatory, and/or antithrombotic therapies. Many of these strategies are currently under evaluation in large-cohort trials and hold promise as affordable, readily available interventions that will improve the postoperative recurrence-free survival of patients with cancer.
- Published
- 2017
35. Effect of beta-blockers on cancer recurrence and survival: a meta-analysis of epidemiological and perioperative studies
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A. Yap, Jonathan G. Hiller, Vijaya Gottumukkala, Erica K. Sloan, R. Schier, Bernhard Riedel, Maria A. Lopez-Olivo, Julia Dubowitz, and Gregory F. Pratt
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0301 basic medicine ,Oncology ,medicine.medical_specialty ,Adrenergic beta-Antagonists ,Disease-Free Survival ,03 medical and health sciences ,Prostate cancer ,0302 clinical medicine ,Internal medicine ,Neoplasms ,medicine ,Humans ,Lung cancer ,Perioperative Period ,business.industry ,Endometrial cancer ,Hazard ratio ,Perioperative ,medicine.disease ,Survival Analysis ,Newcastle–Ottawa scale ,030104 developmental biology ,Anesthesiology and Pain Medicine ,030220 oncology & carcinogenesis ,Meta-analysis ,Neoplasm Recurrence, Local ,business ,Ovarian cancer - Abstract
Background The biological perturbation associated with psychological and surgical stress is implicated in cancer recurrence. Preclinical evidence suggests that beta-blockers can be protective against cancer progression. We undertook a meta-analysis of epidemiological and perioperative clinical studies to investigate the association between beta-blocker use and cancer recurrence (CR), disease-free survival (DFS), and overall survival (OS). Methods Databases were searched until September 2017, reported hazard ratios (HRs) pooled, and 95% confidence intervals (CIs) calculated. Comparative studies examining the effect of beta-blockers (selective and non-selective) on cancer outcomes were included. The Newcastle Ottawa Scale was used to assess methodological quality and bias. Results Of the 27 included studies, nine evaluated the incidental use of non-selective beta-blockers, and ten were perioperative studies. Beta-blocker use had no effect on CR. Within subgroups of cancer, melanoma was associated with improved DFS (HR 0.03, 95% CI 0.01–0.17) and OS (HR 0.04, 95% CI 0.00–0.38), while endometrial cancer had an associated reduction in DFS (HR 1.40, 95% CI 1.10–1.80) and OS (HR 1.50, 95% CI 1.12–2.00). There was also reduced OS seen with head and neck and prostate cancer. Non-selective beta-blocker use was associated with improved DFS and OS in ovarian cancer, improved DFS in melanoma, but reduced OS in lung cancer. Perioperative studies showed similar variable effects across cancer types, albeit from a limited data pool. Conclusion Beta-blocker use had no evident effect on CR. The beneficial effect of beta-blockers on DFS and OS in the epidemiological or perioperative setting remains variable, tumour-specific, and of low-level evidence at present.
- Published
- 2017
36. Perioperative epidural analgesia reduces cancer recurrence after gastro-oesophageal surgery
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Emma Link, Jonathan G. Hiller, Bernhard Riedel, K. L. Wessels, and M. B. Hacking
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medicine.medical_specialty ,Univariate analysis ,business.industry ,Pathological staging ,medicine.medical_treatment ,Hazard ratio ,Subgroup analysis ,General Medicine ,Perioperative ,Surgery ,Anesthesiology and Pain Medicine ,medicine ,Gastrectomy ,Prospective cohort study ,business ,Survival analysis - Abstract
Background: Recent interest has focused on the role of perioperative epidural analgesia in improving cancer outcomes. The heterogeneity of studies (tumour type, stage and outcome endpoints) has produced inconsistent results. Clinical practice also highlights the variability in epidural effectiveness. We considered the novel hypothesis that effective epidural analgesia improves cancer outcomes following gastro-oesophageal cancer surgery in patients with grouped pathological staging. Methods: Following institutional approval, a database analysis identified 140 patients, with 2-year minimum follow-up after gastro-oesophageal cancer surgery. All patients were operated on by a single surgeon (2005‐2010). Information pertaining to cancer and survival outcomes was extracted. Results: Univariate analysis demonstrated a 1-year 14% vs. 33% (P = 0.01) and 2-year 27% vs. 40% [hazard ratio (HR)=0.59; 95% CI, 0.32‐1.09, P = 0.087] incidence of cancer recurrence in patients with (vs. without) effective (> 36 h duration) epidural analgesia, respectively. Multivariate analysis demonstrated increased time to cancer recurrence (HR = 0.33; 95% CI: 0.17‐ 0.63, P < 0.0001) and overall survival benefit (HR = 0.42; 95% CI: 0.21‐0.83, P < 0.0001) at 2-year follow-up following effective epidural analgesia. Subgroup analysis identified epidural-related cancer recurrence benefit in patients with oesophageal cancer (HR = 0.34; 95% CI: 0.16‐0.75, P = 0.005) and in patients with tumour lymphovascular space infiltration (LVSI), (HR = 0.49; 95% CI: 0.26‐0.94, P = 0.03). Effective epidural analgesia improved estimated median time to death (2.9 vs. 1.8 years, P = 0.029) in patients with tumour LVSI. Conclusions: This study found an association between effective post-operative epidural analgesia and medium-term benefit on cancer recurrence and survival following oesophageal surgery. A prospective study that controls for disease type, stage and epidural effectiveness is warranted.
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- 2014
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37. Advantages of low pressure carburising and high pressure gas quenching technology in manufacturing
- Author
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G. Hiller
- Subjects
Gas quenching ,Quenching ,Engineering ,Integrated manufacturing ,business.industry ,Treatment process ,Mechanical engineering ,General Materials Science ,Surface oxidation ,High pressure gas ,business ,Heat treating ,Cost savings - Abstract
Over the last decade, vacuum carburising in combination with high pressure gas quenching (HPGQ) has become a preferred technology in gear industry mainly in Europe and North America. Driven by cost savings in manufacturing of gears and shafts, the heat treatment process has gone into the focus of the manufacturers. The potential of savings in heat treatment is huge because the new technology allows the integration into the manufacturing chain of gears and shafts. With vacuum heat treatment furnaces is it possible to implement this integration into manufacturing. The advantages of vacuum technology are in particular: the absence of surface oxidation, the cold wall technology, the gas quenching technology, the reduced logistics, flexible reaction on the needs of production and the control of distortion. In parallel to the development of the new heat treat process, a second point came into the focus of manufacturers: the choice of material. The industry recognised that by choosing a slightly higher a...
- Published
- 2013
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38. Perioperative Biologic Perturbation and Cancer Surgery: Targeting the Adrenergic-Inflammatory Response and Microcirculatory Dysregulation
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Jonathan G. Hiller, Robert Schier, and Bernhard Riedel
- Subjects
Surgical stress ,business.industry ,medicine.medical_treatment ,Immunosuppression ,Perioperative ,Bioinformatics ,medicine.disease ,Proinflammatory cytokine ,03 medical and health sciences ,0302 clinical medicine ,Immune system ,030202 anesthesiology ,030220 oncology & carcinogenesis ,Anesthesia ,Anesthetic ,medicine ,Endothelial dysfunction ,business ,Adjuvant ,medicine.drug - Abstract
Many of the physiological responses that comprise the surgical stress response are known to promote cancer-signaling pathways. Tissue resection and exposure to the pharmaco-physiological stressors of anesthesia required for surgery activate local and systemic inflammatory cytokines, up-regulate cyclooxygenase with increased prostaglandin production, and increase adrenergic activity. The activation of neuro-hormonal pathways is increasingly linked with cancer propagation. Retrospective evidence suggests that the use of anesthetic techniques and adjuncts that modulate these pathways and commonly available to practicing anesthesiologists may benefit patients scheduled for cancer surgery. Minimising the inflammatory response, preventing perioperative immunosuppression, and optimizing fluid delivery may have oncological benefits (improved disease free survival, reduced postoperative complications with timely delivery of adjuvant therapies) that extend beyond enhanced postoperative recovery. This review will consider key components of local and systemic inflammatory response, relevant immune cell mediators, perioperative endothelial dysfunction, and relevant perioperative therapies specific to the care of the patient receiving cancer surgery.
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- 2017
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39. The Combined Blockade of β-Adrenoceptor and COX-2 During the Perioperative Period to Improve Long-term Cancer Outcomes
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Itay Ricon, Jonathan G. Hiller, and Shamgar Ben-Eliyahu
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Prostaglandin Antagonists ,Adrenergic beta-Antagonists ,Perioperative Care ,β adrenoceptor ,03 medical and health sciences ,0302 clinical medicine ,Text mining ,Catecholamines ,Postoperative Complications ,Stress, Physiological ,Neoplasms ,Medicine ,Humans ,Perioperative Period ,Inflammation ,Cyclooxygenase 2 Inhibitors ,business.industry ,Anti-Inflammatory Agents, Non-Steroidal ,Cancer ,Perioperative ,medicine.disease ,Term (time) ,Blockade ,Receptors, Adrenergic ,Anesthesiology and Pain Medicine ,Treatment Outcome ,030220 oncology & carcinogenesis ,Anesthesia ,Disease Progression ,Prostaglandins ,business ,030217 neurology & neurosurgery - Published
- 2016
40. Impact of celecoxib on inflammation during cancer surgery: a randomized clinical trial
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Niketh Kuruvilla, Rosemary Millen, Shienny Sampurno, Robert G. Ramsay, Bernhard Riedel, Kwok M. Ho, and Jonathan G. Hiller
- Subjects
0301 basic medicine ,Oncology ,Male ,medicine.medical_specialty ,Inflammation ,Substance P ,law.invention ,Metastasis ,03 medical and health sciences ,0302 clinical medicine ,Breast cancer ,Randomized controlled trial ,law ,Anesthesiology ,Internal medicine ,Neoplasms ,medicine ,Humans ,Prospective Studies ,Prospective cohort study ,Aged ,Pain, Postoperative ,Cyclooxygenase 2 Inhibitors ,business.industry ,General Medicine ,Perioperative ,Middle Aged ,medicine.disease ,Surgery ,030104 developmental biology ,Anesthesiology and Pain Medicine ,Celecoxib ,030220 oncology & carcinogenesis ,Anesthesia ,Female ,medicine.symptom ,business ,medicine.drug ,Follow-Up Studies - Abstract
During cancer surgery, prostaglandin-mediated inflammation may promote and activate micrometastatic disease with a consequent increase in long-term cancer recurrence. Cyclooxygenase-2 inhibitors, known to have anti-proliferative properties, may offset such perioperative perturbation. We investigated the effectiveness of these agents to minimize inflammatory changes during cancer surgery.Following ethics approval, 32 patients who were to undergo major intracavity cancer surgery were enrolled in this prospective, randomized, clinical trial. The treatment group received 400 mg celecoxib preoperatively followed by five 200 mg 12-hourly doses. The control group received no anti-inflammatory agents. Inflammatory and immunomodulatory end points were measured serially. The primary end points were the measured plasma and urinary prostaglandin E metabolite (PGENo differences in the 48-hr plasma or urinary PGEStandard dosing of the cyclooxygenase-2 inhibitor celecoxib slightly reduced perioperative cyclooxygenase activity during cancer surgery. Given cyclooxygenase's role in cancer pathways, we recommend dose-finding studies be undertaken before prospective clinical trials are conducted testing the currently unsubstantiated hypothesis that perioperative anti-inflammatory administration improves long-term cancer outcomes. This trial was registered at: Australian New Zealand Clinical Trial Registry: ACTRN12615000041550; www.anzctr.org.au.
- Published
- 2016
41. Improving trial design in cancer anesthesia (onco-anesthesia) research
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Robert G. Ramsay, Paul S. Myles, Bernhard Riedel, and Jonathan G. Hiller
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Research design ,medicine.medical_specialty ,medicine.medical_treatment ,Pain medicine ,MEDLINE ,03 medical and health sciences ,0302 clinical medicine ,Anesthesiology ,030202 anesthesiology ,Neoplasms ,medicine ,Humans ,Anesthesia ,Neoadjuvant therapy ,Randomized Controlled Trials as Topic ,business.industry ,Neoplasms therapy ,Cancer ,General Medicine ,medicine.disease ,Neoadjuvant Therapy ,Anesthesiology and Pain Medicine ,Research Design ,business ,030217 neurology & neurosurgery - Published
- 2017
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42. Four-wave-mixing spectroscopy of peridinin in solution and in the peridinin–chlorophyll-a protein
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Tomáš Polívka, Pavel Chábera, Tõnu Pullerits, Niklas Christensson, and Roger G. Hiller
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Four-wave mixing ,chemistry.chemical_compound ,Peridinin ,Chemistry ,Kinetics ,Relaxation (NMR) ,Phase (waves) ,Analytical chemistry ,General Physics and Astronomy ,Physical and Theoretical Chemistry ,Grating ,Spectroscopy ,Signal - Abstract
A model for the third order optical response of carotenoids is used to analyse transient grating and pump-probe data of peridinin in solution and bound in the peridinin-chlorophyll protein (PCP). For peridinin in solution, the transient grating signal detected at 505 nm exhibits a bi-exponential recovery whose fast phase is assigned to relaxation from the S-2 state that has a lifetime of 75 +/- 25 fs. The slower, solvent-dependent rise component is assigned to equilibration of the (S-1/ICT) state, taking place on a time scale of 0.6 and similar to 2.5 ps in acetontrile and benzene, respectively. These dynamics match those obtained from pump-probe measured in the spectral region of the ICT state, implying that the ICT state contributes to the signal at 505 nm. In PCP, the transient grating signal shows distinctly different kinetics, and the signal shows no recovery. This difference is explained by energy transfer from peridinin to chlorophyll-a. (C) 2009 Elsevier B. V. All rights reserved. (Less)
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- 2010
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43. Identification of a single peridinin sensing Chl- a excitation in reconstituted PCP by crystallography and spectroscopy
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Tomáš Polívka, Roger G. Hiller, Harry A. Frank, Dariusz M. Niedzwiedzki, Eckhard Hofmann, Robert R. Birge, and Tim Schulte
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Chlorophyll ,Models, Molecular ,Mutant ,Protozoan Proteins ,Crystal structure ,Biology ,Crystallography, X-Ray ,Protein Structure, Secondary ,chemistry.chemical_compound ,Protein structure ,Mutant protein ,Protein Isoforms ,Binding site ,Binding Sites ,Multidisciplinary ,Chlorophyll A ,Spectrum Analysis ,Biological Sciences ,Carotenoids ,Recombinant Proteins ,Crystallography ,Peridinin ,chemistry ,Thylakoid ,Mutant Proteins ,Protein Multimerization - Abstract
The peridinin-chlorophyll a -protein (PCP) of dinoflagellates is unique among the large variety of natural photosynthetic light-harvesting systems. In contrast to other chlorophyll protein complexes, the soluble PCP is located in the thylakoid lumen, and the carotenoid pigments outnumber the chlorophylls. The structure of the PCP complex consists of two symmetric domains, each with a central chlorophyll a (Chl- a ) surrounded by four peridinin molecules. The protein provides distinctive surroundings for the pigment molecules, and in PCP, the specific environment around each peridinin results in overlapping spectral line shapes, suggestive of different functions within the protein. One particular Per, Per-614, is hypothesized to show the strongest electronic interaction with the central Chl- a . We have performed an in vitro reconstitution of pigments into recombinant PCP apo-protein (RFPCP) and into a mutated protein with an altered environment near Per-614. Steady-state and transient optical spectroscopic experiments comparing the RFPCP complex with the reconstituted mutant protein identify specific amino acid-induced spectral shifts. The spectroscopic assignments are reinforced by a determination of the structures of both RFPCP and the mutant by x-ray crystallography to a resolution better than 1.5 Å. RFPCP and mutated RFPCP are unique in representing crystal structures of in vitro reconstituted light-harvesting pigment-protein complexes.
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- 2009
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44. Triplet–triplet energy transfer in Peridinin-Chlorophyll a-protein reconstituted with Chl a and Chl d as revealed by optically detected magnetic resonance and pulse EPR: Comparison with the native PCP complex from Amphidinium carterae
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Enrico Salvadori, Stefano Ceola, Marilena Di Valentin, Giorgio M. Giacometti, Donatella Carbonera, Giancarlo Agostini, and Roger G. Hiller
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Chlorophyll ,congenital, hereditary, and neonatal diseases and abnormalities ,ved/biology.organism_classification_rank.species ,Protozoan Proteins ,Biophysics ,macromolecular substances ,Zero field splitting ,Photochemistry ,Biochemistry ,law.invention ,Quantitative Biology::Subcellular Processes ,chemistry.chemical_compound ,law ,Amphidinium carterae ,polycyclic compounds ,Animals ,Triplet state ,Electron paramagnetic resonance ,Carotenoid ,Quantitative Biology::Biomolecules ,Quenching (fluorescence) ,Chemistry ,ved/biology ,Pulsed EPR ,Chlorophyll A ,Electron Spin Resonance Spectroscopy ,food and beverages ,Cell Biology ,Peridinin ,Carotenoids ,Triplet ,PCP ,Triplat state ,Energy Transfer ,ODMR ,Dinoflagellida ,EPR ,Steady state (chemistry) - Abstract
The triplet state of the carotenoid peridinin, populated by triplet-triplet energy transfer from photoexcited chlorophyll triplet state, in the reconstituted Peridinin-Chlorophyll a-protein, has been investigated by ODMR (Optically detected magnetic resonance), and pulse EPR spectroscopies. The properties of peridinins associated with the triplet state formation in complexes reconstituted with Chl a and Chl d have been compared to those of the main-form peridinin-chlorophyll protein (MFPCP) isolated from Amphidinium carterae. In the reconstituted samples no signals due to the presence of chlorophyll triplet states have been detected, during either steady state illumination or laser-pulse excitation. This demonstrates that reconstituted complexes conserve total quenching of chlorophyll triplet states, despite the biochemical treatment and reconstitution with the non-native Chl d pigment. Zero field splitting parameters of the peridinin triplet states are the same in the two reconstituted samples and slightly smaller than in native MFPCP. Analysis of the initial polarization of the photoinduced Electron-Spin-Echo detected spectra and their time evolution, shows that, in the reconstituted complexes, the triplet state is probably localized on the same peridinin as in native MFPCP although, when Chl d replaces Chl a, a local rearrangement of the pigments is likely to occur. Substitution of Chl d for Chl a identifies previously unassigned bands at approximately 620 and approximately 640 nm in the Triplet-minus-Singlet (T-S) spectrum of PCP detected at cryogenic temperature, as belonging to peridinin.
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- 2009
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45. Excited State Structural Dynamics of the Charge Transfer State of Peridinin
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Matthew A. Prantil, Graham R. Fleming, Aaron J. Van Tassle, and Roger G. Hiller
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chemistry.chemical_compound ,Peridinin ,Chemistry ,Infrared ,Excited state ,Relaxation (NMR) ,Ultrafast laser spectroscopy ,General Chemistry ,Methanol ,Internal conversion (chemistry) ,Photochemistry ,Molecular physics ,Excitation - Abstract
We present infrared and visible transient absorption measurements of the first excited singlet state (S 1 and S1/ICT) of peridinin in methanol, isopropanol, and chloroform solution following one-photon excitation, using 490 nm light, to excite the S2 state that populates S1 via rapid (~50 fs in methanol) internal conversion. This technique enables the study of subsequent structural dynamics in S1 involved in the formation of the charge transfer state. The S1 lifetime of peridinin in methanol, isopropanol, and chloroform is found to be 12, 54, and 65 ps, respectively, as deter- mined by infrared transient absorption. We observe two formation timescales in the S1 state. We attribute the shortest timescale to relaxation following internal conver- sion and the longer timescale to formation of the S1/ICT state.
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- 2007
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46. Relative binding affinities of chlorophylls in peridinin–chlorophyll–protein reconstituted with heterochlorophyllous mixtures
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Tatas H. P. Brotosudarmo, Eckhard Hofmann, Sebastian Mackowski, Christoph Bräuchle, Hugo Scheer, and Roger G. Hiller
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Chlorophyll ,Models, Molecular ,Stereochemistry ,ved/biology.organism_classification_rank.species ,Molecular Conformation ,macromolecular substances ,Plant Science ,Crystallography, X-Ray ,Biochemistry ,chemistry.chemical_compound ,Pigment ,Amphidinium carterae ,polycyclic compounds ,Spectroscopy ,Chromatography ,ved/biology ,food and beverages ,Plant physiology ,Cell Biology ,General Medicine ,Carotenoids ,Affinities ,Peridinin ,Monomer ,chemistry ,visual_art ,visual_art.visual_art_medium ,Electrophoresis, Polyacrylamide Gel - Abstract
Peridinin-chlorophyll-protein (PCP), containing differently absorbing chlorophyll derivatives, are good models with which to study energy transfer among monomeric chlorophylls (Chls) by both bulk and single-molecule spectroscopy. They can be obtained by reconstituting the N-terminal domain of the protein (N-PCP) with peridinin and chlorophyll mixtures. Upon dimerization of these "half-mers", homo- and heterochlorophyllous complexes are generated, that correspond structurally to monomeric protomers of native PCP from Amphidinium carterae. Heterochlorophyllous complexes contain two different Chls in the two halves of the complete structure. Here, we report reconstitution of N-PCP with binary mixtures of Chl a, Chl b, and [3-acetyl]-Chl a. The ratios of the pigments were varied in the reconstitution mixture, and relative binding constants were determined from quantification of these pigments in the reconstituted PCPs. We find higher affinities for both Chl b and [3-acetyl]-Chl a than for the native pigment, Chl a.
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- 2007
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47. Energy Transfer in Reconstituted Peridinin-Chlorophyll-Protein Complexes: Ensemble and Single-Molecule Spectroscopy Studies
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Christophe Jung, Roger G. Hiller, Hugo Scheer, Christoph Bräuchle, Stephan Wörmke, Sebastian Mackowski, and Tatas H. P. Brotosudarmo
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Chlorophyll ,Energy transfer ,Photosynthetic Reaction Center Complex Proteins ,Analytical chemistry ,Biophysics ,Photochemistry ,Fluorescence ,Carotenoids ,chemistry.chemical_compound ,Peridinin ,Spectrometry, Fluorescence ,chemistry ,Energy Transfer ,Spinacia oleracea ,Excited state ,Yield (chemistry) ,Dinoflagellida ,Animals ,Absorption (electromagnetic radiation) ,Spectroscopy ,Photobiophysics - Abstract
We combine ensemble and single-molecule spectroscopy to gain insight into the energy transfer between chlorophylls (Chls) in peridinin-chlorophyll-protein (PCP) complexes reconstituted with Chl a, Chl b, as well as both Chl a and Chl b. The main focus is the heterochlorophyllous system (Chl a/b-N-PCP), and reference information essential to interpret experimental observations is obtained from homochlorophyllous complexes. Energy transfer between Chls in Chl a/b-N-PCP takes place from Chl b to Chl a and also from Chl a to Chl b with comparable Förster energy transfer rates of 0.0324 and 0.0215ps−1, respectively. Monte Carlo simulations yield the ratio of 39:61 for the excitation distribution between Chl a and Chl b, which is larger than the equilibrium distribution of 34:66. An average Chl a/Chl b fluorescence intensity ratio of 66:34 is measured, however, for single Chl a/b-N-PCP complexes excited into the peridinin (Per) absorption. This difference is attributed to almost three times more efficient energy transfer from Per to Chl a than to Chl b. The results indicate also that due to bilateral energy transfer, the Chl system equilibrates only partially during the excited state lifetimes.
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- 2007
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48. Monitoring fluorescence of individual chromophores in peridinin–chlorophyll–protein complex using single molecule spectroscopy
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Christophe Jung, Hugo Scheer, Roger G. Hiller, Christoph Bräuchle, Eckhard Hofmann, Sebastian Mackowski, Stephan Wörmke, Moritz Ehrl, Andreas Zumbusch, and Tatas H. P. Brotosudarmo
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Chlorophyll ,Protein Conformation ,ved/biology.organism_classification_rank.species ,Light-Harvesting Protein Complexes ,Protozoan Proteins ,Biophysics ,Photochemistry ,Biochemistry ,Fluorescence ,Light-harvesting complex ,chemistry.chemical_compound ,Amphidinium carterae ,Animals ,Chromophore interaction ,ved/biology ,Chlorophyll A ,Cell Biology ,Chromophore ,Single-molecule experiment ,Carotenoids ,Spectrometry, Fluorescence ,Monomer ,Peridinin ,chemistry ,Absorption band ,ddc:540 ,Dinoflagellida ,Light-harvesting complexes ,Single molecule spectroscopy - Abstract
Single molecule spectroscopy experiments are reported for native peridinin–chlorophyll a–protein (PCP) complexes, and three reconstituted light-harvesting systems, where an N-terminal construct of native PCP from Amphidinium carterae has been reconstituted with chlorophyll (Chl) mixtures: with Chl a, with Chl b and with both Chl a and Chl b. Using laser excitation into peridinin (Per) absorption band we take advantage of sub-picosecond energy transfer from Per to Chl that is order of magnitude faster than the Forster energy transfer between the Chl molecules to independently populate each Chl in the complex. The results indicate that reconstituted PCP complexes contain only two Chl molecules, so that they are spectroscopically equivalent to monomers of native-trimeric-PCP and do not aggregate further. Through removal of ensemble averaging we are able to observe for single reconstituted PCP complexes two clear steps in fluorescence intensity timetraces attributed to subsequent bleaching of the two Chl molecules. Importantly, the bleaching of the first Chl affects neither the energy nor the intensity of the emission of the second one. Since in strongly interacting systems Chl is a very efficient quencher of the fluorescence, this behavior implies that the two fluorescing Chls within a PCP monomer interact very weakly with each other which makes it possible to independently monitor the fluorescence of each individual chromophore in the complex. We apply this property, which distinguishes PCP from other light-harvesting systems, to measure the distribution of the energy splitting between two chemically identical Chl a molecules contained in the PCP monomer that reaches 280 cm− 1. In agreement with this interpretation, stepwise bleaching of fluorescence is also observed for native PCP complexes, which contain six Chls. Most PCP complexes reconstituted with both Chl a and Chl b show two emission lines, whose wavelengths correspond to the fluorescence of Chl a and Chl b. This is a clear proof that these two different chromophores are present in a single PCP monomer. Single molecule fluorescence studies of PCP complexes, both native and artificially reconstituted with chlorophyll mixtures, provide new and detailed information necessary to fully understand the energy transfer in this unique light-harvesting system.
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- 2007
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49. Triplet state dynamics in peridinin-chlorophyll-a-protein: A new pathway of photoprotection in LHCs?
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John T. M. Kennis, Ivo H. M. van Stokkum, Daniel C. Lührs, Roger G. Hiller, Rienk van Grondelle, Maxime T. A. Alexandre, Marie Louise Groot, Biophysics Photosynthesis/Energy, and Biophotonics and Medical Imaging
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Photochemistry ,ved/biology.organism_classification_rank.species ,Biophysics ,Light-Harvesting Protein Complexes ,Protozoan Proteins ,Spectral line ,Biophysical Phenomena ,Delocalized electron ,chemistry.chemical_compound ,Amphidinium carterae ,Spectroscopy, Fourier Transform Infrared ,Animals ,Triplet state ,Conformational isomerism ,Photobiophysics ,Molecular Structure ,ved/biology ,Chemistry ,Carotenoids ,Peridinin ,Models, Chemical ,Photoprotection ,Dinoflagellida ,Thermodynamics ,Excitation - Abstract
This work investigates the interaction of carotenoid and chlorophyll triplet states in the peridinin-chlorophyll-a-protein (PCP) of Amphidinium carterae using step-scan Fourier transform infrared spectroscopy. We identify two carotenoid triplet state lifetimes of approximately 13 and approximately 42 mus in the spectral region between 1800 and 1100 cm(-1) after excitation of the 'blue' and 'red' peridinin (Per) conformers and the Q(y) of chlorophyll-a (Chl-a). The fast and slow decaying triplets exhibit different spectral signatures in the carbonyl region. The fast component generated at all excitation wavelengths is from a major conformer with a lactone stretching mode bleach at 1745 cm(-1). One (1720 cm(-1)) and two (1720 cm(-1) and 1741 cm(-1)) different Per conformers are observed for the slow component upon 670- and 530-480-nm excitation, respectively. The above result implies that (3)Per triplets are formed via two different pathways, corroborating and complementing visible triplet-singlet (T-S) spectra (Kleima et al., Biochemistry (2000), 39, 5184). Surprisingly, all difference spectra show that Per and Chl-a modes are simultaneously present during the (3)Per decay, implying significant involvement of (3)Chl-a in the (3)Per state. We suggest that this Per-Chl-a interaction via a delocalized triplet state lowers the (3)Per energy and thus provides a general, photoprotection mechanism for light-harvesting antenna complexes.
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- 2007
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50. Pigment organisation in the membrane-intrinsic major light-harvesting complex of Amphidinium carterae: Structural characterisation of the peridinins and chlorophylls a and c2 by resonance Raman spectroscopy and from sequence analysis
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Roger G. Hiller, Bruno Robert, Lavanya Premvardhan, Institut de Biologie et de Technologies de Saclay ( IBITECS ), Université Paris-Saclay-Commissariat à l'énergie atomique et aux énergies alternatives ( CEA ), Laboratoire Bioénergétique, Métalloprotéines et Stress ( LBMS ), Département Biochimie, Biophysique et Biologie Structurale ( B3S ), Institut de Biologie Intégrative de la Cellule ( I2BC ), Université Paris-Saclay-Centre National de la Recherche Scientifique ( CNRS ) -Commissariat à l'énergie atomique et aux énergies alternatives ( CEA ) -Université Paris-Sud - Paris 11 ( UP11 ) -Université Paris-Saclay-Centre National de la Recherche Scientifique ( CNRS ) -Commissariat à l'énergie atomique et aux énergies alternatives ( CEA ) -Université Paris-Sud - Paris 11 ( UP11 ) -Institut de Biologie Intégrative de la Cellule ( I2BC ), Université Paris-Saclay-Centre National de la Recherche Scientifique ( CNRS ) -Commissariat à l'énergie atomique et aux énergies alternatives ( CEA ) -Université Paris-Sud - Paris 11 ( UP11 ) -Université Paris-Saclay-Centre National de la Recherche Scientifique ( CNRS ) -Commissariat à l'énergie atomique et aux énergies alternatives ( CEA ) -Université Paris-Sud - Paris 11 ( UP11 ), Department of Biological Sciences and Climate Futures - Macquarie University, Institut de Biologie et de Technologies de Saclay (IBITECS), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, Laboratoire Bioénergétique Membranaire et Stress (LBMS), Département Biochimie, Biophysique et Biologie Structurale (B3S), Institut de Biologie Intégrative de la Cellule (I2BC), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Institut de Biologie Intégrative de la Cellule (I2BC), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), and Université Paris-Saclay-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)
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Chlorophyll c2 ,[SDV]Life Sciences [q-bio] ,Pigment binding ,ved/biology.organism_classification_rank.species ,Resonance Raman spectroscopy ,Biophysics ,Context (language use) ,02 engineering and technology ,010402 general chemistry ,Photochemistry ,01 natural sciences ,Biochemistry ,light-harvesting complex ,Peridinin lactone ring modes ,Light-harvesting complex ,symbols.namesake ,chemistry.chemical_compound ,Amphidinium carterae ,Spectroscopy ,[ SDV ] Life Sciences [q-bio] ,Chemistry ,ved/biology ,Diadinoxanthin ,Sequence analysis ,Structure ,Pigment organisation ,Cell Biology ,021001 nanoscience & nanotechnology ,0104 chemical sciences ,Chlorophyll c(2) ,symbols ,0210 nano-technology ,Raman spectroscopy - Abstract
International audience; The structures and environments of the protein-bound peridinins (Pers) and chlorophylls (Chls) a/c2 in the membrane-intrinsic major light-harvesting complex of the dinoflagellate Amphidinium carterae (LHCAmph) are characterised using resonance Raman (RR) spectroscopy with 11 excitation wavelengths, at 77K. The excitation-dependent variation in the CC stretching mode (ν1) suggests the presence of three Pers with conjugation lengths over 8 double bonds (dBs), and one diadinoxanthin, between 413.7 and 528.7nm. Two Perred species are revealed on excitation at 550 and 560nm. These Perred species exhibit anomalously low ν1 values, together with notable resonant enhancement of lactone ring-breathing and -deformation modes. To discern protein-specific effects, the RR spectra are compared to that of Per in polar (acetonitrile), polarisable (toluene) and polar-protic (ethanol) solvents. Resonantly enhanced lactone, ring-breathing (942cm(-1)) and ring-deformation (~650cm(-1)), modes are identified both in solution, and in the protein, and discussed in the context of the mixing of the S1 and S2 states, and formation of the intramolecular charge-transfer (ICT) state. In the Chl-absorbing region, two sets of Chl c2's, and (at least) six Chl a's can be differentiated. With a pigment ratio of 5-6 (Chl a):2 (Chl c2):5-6 (Per):1 Ddx determined from the fit to the RT absorption and 77K RR spectra, sequence comparison of LHCAmp to LHCII, and the diatom LHC, fucoxanthin-chlorophyll-a/c-protein (FCP), a template for the conserved pigment binding sites is proposed, to fill the paucity of structural information in the absence of a crystal structure for LHCAmph.
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- 2015
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