5,145 results on '"HIRSCH, A"'
Search Results
2. Target-Directed Dynamic Combinatorial Chemistry Affords Binders of Mycobacterium tuberculosis IspE
- Author
-
Maria Braun-Cornejo, Camilla Ornago, Vidhisha Sonawane, Jörg Haupenthal, Andreas M. Kany, Eleonora Diamanti, Gwenaëlle Jézéquel, Norbert Reiling, Wulf Blankenfeldt, Peter Maas, and Anna K. H. Hirsch
- Subjects
Chemistry ,QD1-999 - Published
- 2024
- Full Text
- View/download PDF
3. Overview: quasi-Lagrangian observations of Arctic air mass transformations – introduction and initial results of the HALO–(𝒜 𝒞)3 aircraft campaign
- Author
-
M. Wendisch, S. Crewell, A. Ehrlich, A. Herber, B. Kirbus, C. Lüpkes, M. Mech, S. J. Abel, E. F. Akansu, F. Ament, C. Aubry, S. Becker, S. Borrmann, H. Bozem, M. Brückner, H.-C. Clemen, S. Dahlke, G. Dekoutsidis, J. Delanoë, E. De La Torre Castro, H. Dorff, R. Dupuy, O. Eppers, F. Ewald, G. George, I. V. Gorodetskaya, S. Grawe, S. Groß, J. Hartmann, S. Henning, L. Hirsch, E. Jäkel, P. Joppe, O. Jourdan, Z. Jurányi, M. Karalis, M. Kellermann, M. Klingebiel, M. Lonardi, J. Lucke, A. E. Luebke, M. Maahn, N. Maherndl, M. Maturilli, B. Mayer, J. Mayer, S. Mertes, J. Michaelis, M. Michalkov, G. Mioche, M. Moser, H. Müller, R. Neggers, D. Ori, D. Paul, F. M. Paulus, C. Pilz, F. Pithan, M. Pöhlker, V. Pörtge, M. Ringel, N. Risse, G. C. Roberts, S. Rosenburg, J. Röttenbacher, J. Rückert, M. Schäfer, J. Schaefer, V. Schemann, I. Schirmacher, J. Schmidt, S. Schmidt, J. Schneider, S. Schnitt, A. Schwarz, H. Siebert, H. Sodemann, T. Sperzel, G. Spreen, B. Stevens, F. Stratmann, G. Svensson, C. Tatzelt, T. Tuch, T. Vihma, C. Voigt, L. Volkmer, A. Walbröl, A. Weber, B. Wehner, B. Wetzel, M. Wirth, and T. Zinner
- Subjects
Physics ,QC1-999 ,Chemistry ,QD1-999 - Abstract
Global warming is amplified in the Arctic. However, numerical models struggle to represent key processes that determine Arctic weather and climate. To collect data that help to constrain the models, the HALO–(𝒜𝒞)3 aircraft campaign was conducted over the Norwegian and Greenland seas, the Fram Strait, and the central Arctic Ocean in March and April 2022. The campaign focused on one specific challenge posed by the models, namely the reasonable representation of transformations of air masses during their meridional transport into and out of the Arctic via northward moist- and warm-air intrusions (WAIs) and southward marine cold-air outbreaks (CAOs). Observations were made over areas of open ocean, the marginal sea ice zone, and the central Arctic sea ice. Two low-flying and one long-range, high-altitude research aircraft were flown in colocated formation whenever possible. To follow the air mass transformations, a quasi-Lagrangian flight strategy using trajectory calculations was realized, enabling us to sample the same moving-air parcels twice along their trajectories. Seven distinct WAI and 12 CAO cases were probed. From the quasi-Lagrangian measurements, we have quantified the diabatic heating/cooling and moistening/drying of the transported air masses. During CAOs, maximum values of 3 K h−1 warming and 0.3 g kg−1 h−1 moistening were obtained below 1 km altitude. From the observations of WAIs, diabatic cooling rates of up to 0.4 K h−1 and a moisture loss of up to 0.1 g kg−1 h−1 from the ground to about 5.5 km altitude were derived. Furthermore, the development of cloud macrophysical (cloud-top height and horizontal cloud cover) and microphysical (liquid water path, precipitation, and ice index) properties along the southward pathways of the air masses were documented during CAOs, and the moisture budget during a specific WAI event was estimated. In addition, we discuss the statistical frequency of occurrence of the different thermodynamic phases of Arctic low-level clouds, the interaction of Arctic cirrus clouds with sea ice and water vapor, and the characteristics of microphysical and chemical properties of Arctic aerosol particles. Finally, we provide a proof of concept to measure mesoscale divergence and subsidence in the Arctic using data from dropsondes released during the flights.
- Published
- 2024
- Full Text
- View/download PDF
4. Implementing Concepts of Pharmaceutical Engineering into High School Science Classrooms
- Author
-
Kimmel, Howard, Hirsch, Linda S., and Simon, Laurent
- Abstract
The Research Experience for Teachers was designed to help high school science teachers develop skills and knowledge in research, science and engineering with a focus on the area of pharmaceutical particulate and composite systems. The experience included time for the development of instructional modules for classroom teaching. Results of the evaluation indicate teachers felt the experience was useful and that they were prepared to teach the engineering skills they learned.
- Published
- 2009
5. Lewis Structure Representation of Free Radicals Similar to ClO
- Author
-
Hirsch, Warren and Kobrak, Mark
- Abstract
The study describes the Lewis structure representation of various free radicals, which are quite similar to the ClO radical and its isoelectronic analogues. The analysis of the periodic trends of these radicals shows that oxygen is the most electronegative atom among them.
- Published
- 2007
6. Inhibitors of the Elastase LasB for the Treatment of Pseudomonas aeruginosa Lung Infections
- Author
-
Jelena Konstantinović, Andreas M. Kany, Alaa Alhayek, Ahmed S. Abdelsamie, Asfandyar Sikandar, Katrin Voos, Yiwen Yao, Anastasia Andreas, Roya Shafiei, Brigitta Loretz, Esther Schönauer, Robert Bals, Hans Brandstetter, Rolf W. Hartmann, Christian Ducho, Claus-Michael Lehr, Christoph Beisswenger, Rolf Müller, Katharina Rox, Jörg Haupenthal, and Anna K.H. Hirsch
- Subjects
Chemistry ,QD1-999 - Published
- 2023
- Full Text
- View/download PDF
7. Human–Computer Interaction (HCI) Advances to Re-Contextualize Cultural Heritage toward Multiperspectivity, Inclusion, and Sensemaking
- Author
-
Linda Hirsch, Siiri Paananen, Denise Lengyel, Jonna Häkkilä, Georgios Toubekis, Reem Talhouk, and Luke Hespanhol
- Subjects
cultural heritage ,contextualization ,multiperspectivity ,entanglements ,inclusion ,sensemaking ,Technology ,Engineering (General). Civil engineering (General) ,TA1-2040 ,Biology (General) ,QH301-705.5 ,Physics ,QC1-999 ,Chemistry ,QD1-999 - Abstract
Today’s social and political movements against dominant Western narratives call for a re-contextualization of cultural heritage (CH) toward inclusivity, multiperspectivity, and sensemaking. Our work approaches this challenge from a Human–Computer Interaction (HCI) perspective, questioning how HCI approaches, tools and methods can contribute to CH re-contextualization. Through collaborative reflection on our research practice, we identified four diverging case studies highlighting the different roles of HCI and its increasing entanglement with CH. Case studies 1–3 focus on HCI as a medium for CH, case 4 on digital CH, and thereby on the HCI–CH entanglement. Our reflections contribute to CH re-contextualization by highlighting the need for co-design and slow design approaches, the role of HCI technologies in preserving, communicating, and shaping CH, and open questions and challenges related to the increasing HCI–CH convergence.
- Published
- 2024
- Full Text
- View/download PDF
8. Design of an Optimized Terahertz Time-Domain Spectroscopy System Pumped by a 30 W Yb:KGW Source at a 100 kHz Repetition Rate with 245 fs Pulse Duration
- Author
-
Lennart Hirsch, Dionysis Adamou, Daniele Faccio, Marco Peccianti, and Matteo Clerici
- Subjects
terahertz ,spectroscopy ,Gallium Phosphide ,femtosecond ,ytterbium lasers ,Technology ,Engineering (General). Civil engineering (General) ,TA1-2040 ,Biology (General) ,QH301-705.5 ,Physics ,QC1-999 ,Chemistry ,QD1-999 - Abstract
Ytterbium laser sources are state-of-the-art systems that are increasingly replacing Ti:Sapphire lasers in most applications requiring high repetition rate pulse trains. However, extending these laser sources to THz Time-Domain Spectroscopy (THz-TDS) poses several challenges not encountered in conventional, lower-power systems. These challenges include pump rejection, thermal lensing in nonlinear media, and pulse durations exceeding 100 fs, which consequently limit the detection bandwidth in TDS applications. In this article, we describe our design of a THz-TDS beamline that seeks to address these issues. We report on the effectiveness of temperature controlling the Gallium Phosphide (GaP) used to generate the THz radiation and its impact on increasing the generation efficiency and aiding pump rejection while avoiding thermal distortions of the residual pump laser beam. We detail our approach to pump rejection, which can be implemented with off-the-shelf products and minimal customization. Finally, we describe our solution based on a commercial optical parametric amplifier to obtain a temporally compressed probe pulse of 55 fs duration. Our study will prove useful to the increasing number of laboratories seeking to move from the high-energy, low-power THz time-domain spectroscopy systems based on Ti:Sapphire lasers, to medium-energy, high-power systems driven by Yb-doped lasers.
- Published
- 2024
- Full Text
- View/download PDF
9. Unconventional conductivity increase in multilayer black phosphorus
- Author
-
Maria Koleśnik-Gray, Laura Meingast, Martin Siebert, Tim Unbehaun, Tobias Huf, Günter Ellrott, Gonzalo Abellán, Stefan Wild, Vicent Lloret, Udo Mundloch, Julian Schwarz, Michael Niebauer, Maximilian Szabo, Mathias Rommel, Andreas Hutzler, Frank Hauke, Andreas Hirsch, and Vojislav Krstić
- Subjects
Materials of engineering and construction. Mechanics of materials ,TA401-492 ,Chemistry ,QD1-999 - Abstract
Abstract Multilayers of so-called 2D van der Waals materials have gained considerable attention as active components of next-generation electronic and optoelectronic technologies, with semiconducting black phosphorus (BP) regarded as one of the most promising systems. The applicability and performance limits of BP in both stand-alone and heterostructure-based multilayer devices are determined by individual flake charge transport properties, which synergistically depend on the number of layers and the strength of interlayer coupling between those. In this work, we study the DC electrical transport characteristics of high-quality BP field-effect devices within a wide range of flake thicknesses at room temperature. The experimental data show a non-trivial increase in conductivity and hole density with a reduced number of layers while maintaining constant field-effect mobility due to the prevalence of electron–phonon scattering. Based on the solution of the 1D Schrödinger–Poisson equation, we find that the observed phenomena are a direct consequence of non-negligible interlayer coupling, which in turn causes a local redistribution of free charge carriers towards the central layers. Our data show that due to the electrostatic conditions at the flake surfaces, a naturally protected 2D hole gas can be encapsulated in flakes as high as 10 nm, which preserves the bulk-like bandgap and effective carrier masses due to the electrostatic environment.
- Published
- 2023
- Full Text
- View/download PDF
10. Connection-Aware Heuristics for Scheduling and Distributing Jobs under Dynamic Dew Computing Environments
- Author
-
Pablo Sanabria, Sebastián Montoya, Andrés Neyem, Rodrigo Toro Icarte, Matías Hirsch, and Cristian Mateos
- Subjects
dew computing ,reinforcement learning ,connection-aware scheduling ,mobility models ,heuristics ,transfer learning ,Technology ,Engineering (General). Civil engineering (General) ,TA1-2040 ,Biology (General) ,QH301-705.5 ,Physics ,QC1-999 ,Chemistry ,QD1-999 - Abstract
Due to the widespread use of mobile and IoT devices, coupled with their continually expanding processing capabilities, dew computing environments have become a significant focus for researchers. These environments enable resource-constrained devices to contribute computing power to a local network. One major challenge within these environments revolves around task scheduling, specifically determining the optimal distribution of jobs across the available devices in the network. This challenge becomes particularly pronounced in dynamic environments where network conditions constantly change. This work proposes integrating the “reliability” concept into cutting-edge human-design job distribution heuristics named ReleSEAS and RelBPA as a means of adapting to dynamic and ever-changing network conditions caused by nodes’ mobility. Additionally, we introduce a reinforcement learning (RL) approach, embedding both the notion of reliability and real-time network status into the RL agent. Our research rigorously contrasts our proposed algorithms’ throughput and job completion rates with their predecessors. Simulated results reveal a marked improvement in overall throughput, with our algorithms potentially boosting the environment’s performance. They also show a significant enhancement in job completion within dynamic environments compared to baseline findings. Moreover, when RL is applied, it surpasses the job completion rate of human-designed heuristics. Our study emphasizes the advantages of embedding inherent network characteristics into job distribution algorithms for dew computing. Such incorporation gives them a profound understanding of the network’s diverse resources. Consequently, this insight enables the algorithms to manage resources more adeptly and effectively.
- Published
- 2024
- Full Text
- View/download PDF
11. Rubber Bands, Free Energy, and Le Chatelier's Principle.
- Author
-
Hirsch, Warren
- Abstract
Describes an activity using rubber bands to demonstrate Gibbs free energy, entropy, and enthalpy. Includes instructor information and a student activity sheet. (YDS)
- Published
- 2002
12. A Profile of Michigan Teachers of High School Biology, Chemistry, and Physics: 1980-1983.
- Author
-
Hirsch, Christian R.
- Abstract
Provides a profile of Michigan high school biology, chemistry, and physics teachers for the 1980-81, 1981-82, and 1982-83 school years, including highest degree(s), major(s), minor(s), sex, years of teaching experience, type of certificate, and assignment(s). Also examines possible trends in the staffing of high school science courses in Michigan. (JN)
- Published
- 1984
13. Computer Series, 43: Chemometrics in the Chemistry Curriculum.
- Author
-
Howery, Darryl G. and Hirsch, Roland F.
- Abstract
Discusses chemometrics (analysis of data from chemical measurements), tracing developments in this area and summarizing reasons for teaching chemometrics. Includes highlights of presentations given at a symposium (Interpreting Complex Chemical Data: Teaching Chemometrics) and brief descriptions of chemometric methods. (JN)
- Published
- 1983
14. An Analysis of Underused Urban Infrastructures: Usage Opportunities and Implementation Barriers for Sustainable Logistics
- Author
-
Larissa Schachenhofer, Yvonne Kummer, and Patrick Hirsch
- Subjects
sustainable urban logistics plan ,freight transport ,innovative city logistics ,underused urban infrastructure ,logistics barriers ,Technology ,Engineering (General). Civil engineering (General) ,TA1-2040 ,Biology (General) ,QH301-705.5 ,Physics ,QC1-999 ,Chemistry ,QD1-999 - Abstract
Motivated by the urgent need to discover innovative and sustainable approaches to address the strain on urban resources, this paper introduces a novel concept proposing the utilization of “sleeping assets”. These sleeping assets encompass three distinct categories of urban infrastructures: neglected routes, idle real estate, and underused resources. By harnessing these assets, cities can alleviate the intense competition for land, traffic infrastructure, and parking areas. The findings presented in this paper are derived from an extensive literature study and expert interviews conducted with relevant stakeholders from Hamburg, Paris, Stockholm, and Vienna. Building upon the most pertinent insights from the literature and a structured content analysis of the interviews, we outline the advantages of employing sleeping assets for urban logistics initiatives. Additionally, we identify seven main categories of implementation barriers that must be taken into account. The results of this study reveal political and legislative barriers as one of the major impeding factors in initiating the utilization of sleeping assets. To address these barriers, this paper points towards crucial leverage for cities and provides an outlook on possible forms of sustainable urban logistics implementation. Thus, this work can support researchers as well as practitioners from city administrations and urban logistics interested in using sleeping assets by encouraging the exploitation of unused potential and avoiding particular implementation pitfalls.
- Published
- 2023
- Full Text
- View/download PDF
15. Community Masks - from an Emergency Solution to an Innovation Booster for the Textile Industry
- Author
-
Till Batt, Gordon Herwig, Simon Annaheim, Pietro Clement, Lea Furrer, Cordula Hirsch, Vincent Varanges, Baris Caglar, Veronique Michaud, Jing Wang, Gilles Richner, Peter Wick, and René Rossi
- Subjects
COVID-19 pandemic ,antiviral facemask ,air permeability ,wearing comfort ,filtration efficiency ,Chemistry ,QD1-999 - Abstract
The COVID-19 pandemic resulted in shortages of personal protective equipment and medical devices in the initial phase. Agile small and medium-sized enterprises from regional textile industries reacted quickly. They delivered alternative products such as textile-based community masks in collaboration with industrial partners and research institutes from various sectors. The current mask materials and designs were further improved by integrating textiles with antiviral and antimicrobial properties and enhanced protection and comfort by novel textile/membrane combinations, key factors to increase the acceptance and compliance of mask wearing. The innocuity and sustainability of masks, as well as taking into account particular needs of vulnerable persons in our society, are new fields for textile-based innovations. These innovations developed for the next generation of facemasks have a high adaptability to other product segments, which make textiles an attractive material for hygienic applications and beyond.
- Published
- 2022
- Full Text
- View/download PDF
16. Double Network Granular Hydrogels
- Author
-
Matteo Hirsch, Alvaro Charlet, and Esther Amstad
- Subjects
3D printing ,Hydrogel ,Recycling ,Stiffness ,Chemistry ,QD1-999 - Published
- 2022
- Full Text
- View/download PDF
17. A Microfluidic Approach to Investigate the Contact Force Needed for Successful Contact-Mediated Nucleation
- Author
-
Gina Kaysan, Theresa Hirsch, Konrad Dubil, and Matthias Kind
- Subjects
contact-mediated nucleation ,contact force ,emulsion ,crystallization ,CFD ,Chemistry ,QD1-999 - Abstract
Emulsions with crystalline dispersed phase fractions are becoming increasingly important in the pharmaceutical, chemical, and life science industries. They can be produced by using two-stage melt emulsification processes. The completeness of the crystallization step is of particular importance as it influences the properties, quality, and shelf life of the products. Subcooled, liquid droplets in agitated vessels may contact an already crystallized particle, leading to so-called contact-mediated nucleation (CMN). Energetically, CMN is a more favorable mechanism than spontaneous nucleation. The CMN happens regularly because melt emulsions are stirred during production and storage. It is assumed that three main factors influence the efficiency of CNM, those being collision frequency, contact time, and contact force. Not all contacts lead to successful nucleation of the liquid droplet, therefore, we used microfluidic experiments with inline measurements of the differential pressure to investigate the minimum contact force needed for successful nucleation. Numerical simulations were performed to support the experimental data obtained. We were able to show that the minimum contact force needed for CMN increases with increasing surfactant concentration in the aqueous phase.
- Published
- 2023
- Full Text
- View/download PDF
18. Comparison of Topic Modelling Approaches in the Banking Context
- Author
-
Bayode Ogunleye, Tonderai Maswera, Laurence Hirsch, Jotham Gaudoin, and Teresa Brunsdon
- Subjects
kernel pca ,k-means clustering ,topic extraction ,topic model ,aspect extraction ,natural language processing ,Technology ,Engineering (General). Civil engineering (General) ,TA1-2040 ,Biology (General) ,QH301-705.5 ,Physics ,QC1-999 ,Chemistry ,QD1-999 - Abstract
Topic modelling is a prominent task for automatic topic extraction in many applications such as sentiment analysis and recommendation systems. The approach is vital for service industries to monitor their customer discussions. The use of traditional approaches such as Latent Dirichlet Allocation (LDA) for topic discovery has shown great performances, however, they are not consistent in their results as these approaches suffer from data sparseness and inability to model the word order in a document. Thus, this study presents the use of Kernel Principal Component Analysis (KernelPCA) and K-means Clustering in the BERTopic architecture. We have prepared a new dataset using tweets from customers of Nigerian banks and we use this to compare the topic modelling approaches. Our findings showed KernelPCA and K-means in the BERTopic architecture-produced coherent topics with a coherence score of 0.8463.
- Published
- 2023
- Full Text
- View/download PDF
19. Impact of Pro-Argin on the Oral Health-Related Quality of Life: A 24-Week Randomized, Parallel-Group, Multicenter Study
- Author
-
Mary Michaelis, Constanze Hirsiger, Dominique Roux, Patrick Roger Schmidlin, Thomas Attin, Sophie Doméjean, Christian Hirsch, Christian Heumann, Hans-Günter Schaller, and Christian Ralf Gernhardt
- Subjects
cervical dentine hypersensitivity ,Pro-Argin ,quality of life ,patient health questionnaire ,Technology ,Engineering (General). Civil engineering (General) ,TA1-2040 ,Biology (General) ,QH301-705.5 ,Physics ,QC1-999 ,Chemistry ,QD1-999 - Abstract
To assess the efficacy of Pro-Argin with respect to the oral health-related quality of life (OHRQoL) and cervical dentine hypersensitivity (CDH) in subjects with CDH for 24 weeks compared to a control group. Three study centers (one each in France, Germany, and Switzerland) included 273 subjects for 24 weeks. Patients with CDH involving at least two non-molar teeth and those with Schiff scores (cold air sensitivity scale) of 2 or 3 were included. The primary study parameter was a change in the OHRQoL from baseline to 24 weeks, as assessed by the Oral Health Impact Profile (OHIP)-49 questionnaire within and between the randomized groups. Patients were randomly assigned to the test group (TG) or the control group (CG). Prophylaxis paste and toothpaste in the TG contained 8% arginine and calcium carbonate. The toothpaste in the CG contained sodium monofluorophosphate. The level of significance was set at 5% (p = 0.05). The OHIP-49 at 24 weeks was analyzed using the analysis of covariance (ANCOVA). The mean OHIP-49 score after 24 weeks (adjusted for baseline) was significantly lower in the TG than in the CG (p = 0.005, ANCOVA). The OHIP-49 pain-related items adjusted for the baseline values also showed significant differences between the groups (p = 0.025, ANCOVA). The treatment over a period of 24 weeks using products based on the Pro-Argin technology showed a significant improvement in the OHRQoL compared to the placebo application.
- Published
- 2022
- Full Text
- View/download PDF
20. Diketo-Pyrrolo Pyrrole-Based Acceptor-Acceptor Copolymers with Deep HOMO and LUMO Levels Absorbing in the Near Infrared
- Author
-
Wissem Khelifi, Hussein Awada, Sylvie Blanc, Gilles Henri Roche, Lionel Hirsch, Bassey Oboho, Frédéric Castet, Antoine Bousquet, and Christine Lartigau-Dagron
- Subjects
copolymer ,near infra-red ,low bandgap ,Technology ,Engineering (General). Civil engineering (General) ,TA1-2040 ,Biology (General) ,QH301-705.5 ,Physics ,QC1-999 ,Chemistry ,QD1-999 - Abstract
A series of acceptor-acceptor (A-A’) alternated copolymers based on dithienodiketopyrrolo pyrrole were synthesized by copolymerizing it with itself and other different electron-poor monomers. The experimental and computed optoelectronic properties of four DPP-based copolymers, P(DPP-DPP) (with linear and branched chains), copolymer with diazapentalene P(DPP-DAP) and also with dioxothienopyrrolebenzodifurandione P(DPP-BTPBF), as well as thermal characterizations were described. UV-visible spectrophotometry and cyclic voltammetry were used to estimate the optical and electrochemical bandgaps, and were found as very small: 1.3, 1.0, and 0.9 eV for P(DPP-DPP), P(DPP-DAP), and P(DPP-BTPBF), respectively. The BTPBF unit allowed a strong reduction of the bandgap, leading to a broad absorption in the visible and near infra-red regions from 650 to 1450 nm. These results were compared to analogous donor-acceptor (D-A) copolymers previously reported, in which DPP is replaced by DTS, P(DTS-DPP), P(DTS-DAP), and P(DTS-BTPBF). The same trend was observed. By comparing A-A’ to D-A’ copolymers analogues, it was shown that the bandgap remained the same while both HOMO and LUMO levels were lowered by roughly 0.2 eV.
- Published
- 2022
- Full Text
- View/download PDF
21. Current Trends in the Optical Characterization of Two-Dimensional Carbon Nanomaterials
- Author
-
Anton Kröner and Thomas Hirsch
- Subjects
graphene ,graphene oxide ,carbon nanomaterial ,optical characterization ,methods ,defects ,Chemistry ,QD1-999 - Abstract
Graphene and graphene-related materials have received great attention because of their outstanding properties like Young's modulus, chemical inertness, high electrical and thermal conductivity, or large mobility. To utilize two-dimensional (2D) materials in any practical application, an excellent characterization of the nanomaterials is needed as such dimensions, even small variations in size, or composition, are accompanied by drastic changes in the material properties. Simultaneously, it is sophisticated to perform characterizations at such small dimensions. This review highlights the wide range of different characterization methods for the 2D materials, mainly attributing carbon-based materials as they are by far the ones most often used today. The strengths as well as the limitations of the individual methods, ranging from light microscopy, scanning electron microscopy, transmission electron microscopy, scanning transmission electron microscopy, scanning tunneling microscopy (conductive), atomic force microscopy, scanning electrochemical microscopy, Raman spectroscopy, UV–vis, X-ray photoelectron spectroscopy, X-ray fluorescence spectroscopy, energy-dispersive X-ray spectroscopy, Auger electron spectroscopy, electron energy loss spectroscopy, X-ray diffraction, inductively coupled plasma atomic emission spectroscopy to dynamic light scattering, are discussed. By using these methods, the flake size and shape, the number of layers, the conductivity, the morphology, the number and type of defects, the chemical composition, and the colloidal properties of the 2D materials can be investigated.
- Published
- 2020
- Full Text
- View/download PDF
22. Liquid-Liquid Separation in Solutions of Normal and Sickle Cell Hemoglobin
- Author
-
Galkin, Oleg, Chen, Kai, Nagel, Ronald L., Hirsch, Rhoda Elison, and Vekilov, Peter G.
- Published
- 2002
23. A Spectroscopic Investigation of Eu3+ Incorporation in LnPO4 (Ln = Tb, Gd1-xLux, X = 0.3, 0.5, 0.7, 1) Ceramics
- Author
-
Henry Lösch, Antje Hirsch, Jacqueline Holthausen, Lars Peters, Bin Xiao, Stefan Neumeier, Moritz Schmidt, and Nina Huittinen
- Subjects
xenotime ,PXRD ,solid solutions ,Eu3+ incorporation ,TRLFS ,grain boundary ,Chemistry ,QD1-999 - Abstract
We have investigated the incorporation of the luminescent Eu3+ cation in different LnPO4 (Ln = Tb, Gd1−xLux, x = 0.3, 0.5, 0.7, 1) host phases. All samples were analyzed with powder X-ray diffraction (PXRD), Raman spectroscopy, and site-selective time-resolved laser-induced luminescence spectroscopy (TRLFS) directly after synthesis and after an aging time of one year at ambient conditions. The PXRD investigations demonstrate the formation of a TbPO4 phase in an uncommon anhydrite-like crystal structure evoked by a pressure-induced preparation step (grinding). In the Gd1−xLuxPO4 solid solution series, several different crystal structures are observed depending on the composition. The TRLFS emission spectra of LuPO4, Gd0.3Lu0.7PO4, and Gd0.5Lu0.5PO4 indicate Eu3+–incorporation within a xenotime-type crystal structure. TRLFS and PXRD investigations of the Gd0.7Lu0.3PO4 composition show the presence of anhydrite, xenotime, and monazite phases, implying that xenotime no longer is the favored crystal structure due to the predominance of the substantially larger Gd3+–cation in this solid phase. Eu3+–incorporation occurs predominantly in the anhydrite-like structure with smaller contributions of Eu3+ incorporated in monazite and xenotime. The electronic levels of the Eu3+–dopant in Gd0.3Lu0.7PO4 and Gd0.5Lu0.5PO4 xenotime hosts are strongly coupled to external lattice vibrations, giving rise to high-energy peaks in the obtained excitation spectra. The coupling becomes stronger after aging to such an extent that direct excitation of Eu3+ in the xenotime structure is strongly suppressed. This phenomenon, however, is only visible for materials where Eu3+ was predominantly incorporated within the xenotime structure. Single crystals of Eu3+–doped LuPO4 show no changes upon aging despite the presence of vibronically coupled excitation peaks in the excitation spectra measured directly after synthesis. Based on this observation, we propose a lattice relaxation process occurring in the powder samples during aging, resulting in Eu3+ migration within the crystal structure and Eu3+ accumulation at grain boundaries or xenotime surface sites.
- Published
- 2019
- Full Text
- View/download PDF
24. Searching the Literature on Government Regulations: An Introduction for Science Students.
- Author
-
Hirsch, Roland F. and Dobrosky, Dolores
- Abstract
Describes a project in which chemistry students search government publications for information on federal regulations of chemical substances. Project goals include developing an awareness of government regulations related to the practice of chemistry, use of documents containing regulations, and exploring library holdings of government publications. (JN)
- Published
- 1983
25. Responsive Contrast Agents: Synthesis and Characterization of a Tunable Series of pH-Sensitive Near-Infrared Pentamethines
- Author
-
Virginia Wycisk, Katharina Achazi, Paul Hillmann, Ole Hirsch, Christian Kuehne, Jens Dernedde, Rainer Haag, and Kai Licha
- Subjects
Chemistry ,QD1-999 - Published
- 2016
- Full Text
- View/download PDF
26. Activity of Systemic Treatments After Cabozantinib Failure in Advanced Metastatic Renal Cell Carcinoma
- Author
-
Vincenzo Di Nunno, Laurence Albiges, Axelle Benchimol-Zouari, Laure Hirsch, Bernard Escudier, Annalisa Guida, L. Cerbone, Lucia Carril Ajuria, Flore Salviat, Ronan Flippot, Emeline Colomba, and Carolina Alves Costa Silva
- Subjects
Male ,Oncology ,medicine.medical_specialty ,Axitinib ,Cabozantinib ,Pyridines ,Angiogenesis ,Urology ,Antineoplastic Agents ,Context (language use) ,Systemic therapy ,chemistry.chemical_compound ,Renal cell carcinoma ,Internal medicine ,Humans ,Medicine ,Anilides ,Everolimus ,Carcinoma, Renal Cell ,Immune Checkpoint Inhibitors ,Protein Kinase Inhibitors ,Retrospective Studies ,business.industry ,Retrospective cohort study ,medicine.disease ,Kidney Neoplasms ,chemistry ,Female ,business ,medicine.drug - Abstract
Background Cabozantinib, a potent multi-tyrosine kinases inhibitor (TKI), has demonstrated overall survival (OS) benefit over everolimus in patients previously treated with VEGFR TKI for metastatic Renal Cell Carcinoma (mRCC). The efficacy of systemic treatments after cabozantinib failure has not been investigated. Methods We conducted a retrospective study on patients receiving systemic treatment after cabozantinib failure in heavily pre-treated patient with mRCC. We assessed Time to Treatment Failure (TTF), OS and objective response rate (ORR). Results Among 150 patients treated with cabozantinib in our institution, 56 (37.3%) received subsequent systemic therapy and were eligible for the analysis. IMDC prognostic group was good, intermediate and poor in 11 (19.6%), 24 (42.9%) and 11 (19.6%) patients, respectively. Cabozantinib was administered mainly as a second (41.1%), or third (33.9%) line treatment. axitinib or immune-checkpoint inhibitors were the subsequent treatment in 18 (34.8%) patients for each everolimus (n:16, 28.6%), other angiogenesis inhibitors (n:4, 7.1%) TTF and OS from subsequent systemic therapy after cabozantinib failure were 2.8 months (95%CI 1.9-3.7) and 7.7 months (95%CI 4.4-10.8), respectively. ORR was 8.7% and two patients with axitinib and two patients treated with Immune checkpoint inhibitors achieved a partial response. Conclusions Overall, activity of systemic therapies after cabozantinib was limited. Micro abstract We performed a retrospective analysis on 56 patients with metastatic renal cell carcinoma who received at least 1 systemic treatment line after cabozantinib. Median OS after cabozantinib was 7.7 months, while median TTF after cabozantinib was 2.8 months. Further investigation is needed in this clinical context
- Published
- 2022
27. Effect of preheating and isothermal holding time on the crystallization, densification and properties of a sintered lithium silicate glass-ceramic
- Author
-
Claudinei dos Santos, Manuel Fellipe Rodrigues Pais Alves, Roberto Hirsch Monteiro, Carlos N. Elias, and Kurt Strecker
- Subjects
Materials science ,Process Chemistry and Technology ,Metallurgy ,chemistry.chemical_element ,Silicate ,Isothermal process ,Surfaces, Coatings and Films ,Electronic, Optical and Magnetic Materials ,law.invention ,chemistry.chemical_compound ,chemistry ,law ,visual_art ,Materials Chemistry ,Ceramics and Composites ,visual_art.visual_art_medium ,Lithium ,Ceramic ,Crystallization ,Silicate glass ,Holding time - Abstract
The objective of this work was to study the effect of different heating-up procedures and isothermal treatment times on crystallization, densification and properties of a sintered non-stoichiometric lithium silicate glass-ceramic. Glass samples containing SiO2, Li2O and K2O as main constituents, besides minor amounts of other oxides such as Al2O3, P2O5 and ZrO2, were melted at 1500 °C - 60 min and subsequently fragmented (
- Published
- 2022
28. A rapid synthesis of low-nanomolar divalent LecA inhibitors in four linear steps from d-galactose pentaacetate
- Author
-
Eva Zahorska, Alexander Titz, Sakonwan Kuhaudomlarp, Martin Lepšík, Saverio Minervini, Anne Imberty, Anna K. H. Hirsch, Sultaan Yousaf, Thorsten Kinsinger, Chemical Biology of Carbohydrates, Helmholtz Institute for Pharmaceutical Research Saarland (HIPS), Centre de Recherches sur les Macromolécules Végétales (CERMAV), Institut de Chimie du CNRS (INC)-Université Grenoble Alpes (UGA)-Centre National de la Recherche Scientifique (CNRS), and HIPS, Helmholtz-Institut für Pharmazeutische Forschung Saarland, Universitätscampus E8.1 66123 Saarbrücken, Germany.
- Subjects
Models, Molecular ,Protein Conformation ,Chemistry Techniques, Synthetic ,010402 general chemistry ,medicine.disease_cause ,01 natural sciences ,Catalysis ,Virulence factor ,Epitope ,Divalent ,Protein structure ,Materials Chemistry ,medicine ,[CHIM]Chemical Sciences ,Adhesins, Bacterial ,ComputingMilieux_MISCELLANEOUS ,chemistry.chemical_classification ,biology ,010405 organic chemistry ,Chemistry ,Pseudomonas aeruginosa ,Metals and Alloys ,Biofilm ,Lectin ,Galactose ,General Chemistry ,0104 chemical sciences ,3. Good health ,Surfaces, Coatings and Films ,Electronic, Optical and Magnetic Materials ,Bacterial adhesin ,Kinetics ,Biochemistry ,Ceramics and Composites ,biology.protein - Abstract
Chronic infections with Pseudomonas aeruginosa are associated with the formation of bacterial biofilms. The tetrameric P. aeruginosa lectin LecA is a virulence factor and an anti-biofilm drug target. Increasing the overall binding affinity by multivalent presentation of binding epitopes can enhance the weak carbohydrate-ligand interactions. Low-nanomolar divalent LecA ligands/inhibitors with up to 260-fold valency-normalized potency boost and excellent selectivity over human galectin-1 were synthesized from d-galactose pentaacetate and benzaldehyde-based linkers in four linear steps.
- Published
- 2023
- Full Text
- View/download PDF
29. Spray-drying of inhalable, multifunctional formulations for the treatment of biofilms formed in cystic fibrosis
- Author
-
Eric Ofosu Kissi, Valentin Sigal, Walid A. M. Elgaher, Nashrawan Lababidi, Anna K. H. Hirsch, Jörg Haupenthal, Marc Schneider, Bianca C. Schwarz, Thomas Rades, and HIPS, Helmholtz-Institut für Pharmazeutische Forschung Saarland, Universitätscampus E8.1 66123 Saarbrücken, Germany.
- Subjects
Cystic Fibrosis ,medicine.drug_class ,Drug Storage ,Antibiotics ,Dry-powder formulation ,Pharmaceutical Science ,02 engineering and technology ,Azithromycin ,Pharmacology ,Salt formation ,medicine.disease_cause ,03 medical and health sciences ,Drug Stability ,Ciprofloxacin ,Administration, Inhalation ,medicine ,Tobramycin ,Animals ,Pseudomonas Infections ,Horses ,Particle Size ,Expectorants ,030304 developmental biology ,0303 health sciences ,Inhalation ,Chemistry ,Pseudomonas aeruginosa ,Co-amorphous drug delivery ,Biofilm ,021001 nanoscience & nanotechnology ,Dry-powder inhaler ,Acetylcysteine ,Anti-Bacterial Agents ,3. Good health ,Mucus ,Biofilms ,Spray drying ,Bacterial infection ,0210 nano-technology ,medicine.drug - Abstract
Cystic fibrosis (CF) is a serious lung disease, commonly susceptible to Pseudomonas aeruginosa colonization. The dense mucus together with biofilm formation limit drug permeability and prevent the drug from reaching the site of action, causing treatment failure of the bacterial infection. Besides the use of antibiotics, the mucolytic agent N-acetylcysteine (NAC) is recommended to be co-administered in the treatment of CF. Although several formulations have been developed for inhalation therapy to improve the pulmonary condition in CF patients, there is still no comprehensive study on a combined multifunctional dry powder formulation of antibiotics with NAC. In this work, we developed an innovative multifunctional dry powder inhaler (DPI) formulation based on salt formation between NAC and antibiotics and characterized their solid state properties and physical stability. NAC could be spray dried together with three different antibiotics, azithromycin (Azi), tobramycin (Tobra) and ciprofloxacin (Cipro), without the use of organic solvents to form Azi/NAC, Tobra/NAC and Cipro/NAC DPI formulations. Solid-state characterization of these DPI formulations showed that they were amorphous after spray drying. Azi/NAC and Tobra/NAC form co-amorphous salt systems that were physically stable under storage at stress conditions. For particle characterization, the obtained mass median aerodynamic diameters were in a suitable range for inhalation (< 5.0μm). The multifunctional antibiotic/NAC formulations conserved or improved the antibiotic susceptibility and showed promising results regarding the inhibition of P. aeruginosa PA14 biofilm formation.
- Published
- 2023
- Full Text
- View/download PDF
30. Semisynthesis and biological evaluation of amidochelocardin derivatives as broad-spectrum antibiotics
- Author
-
Marc Stadler, Fabienne Hennessen, Rolf W. Hartmann, Mark Brönstrup, Samir Yahiaoui, Anna K. H. Hirsch, Rolf Müller, Jennifer Herrmann, Charlotte Grandclaudon, Ravindra P. Jumde, Walid A. M. Elgaher, Stephan Hüttel, N.V. Suryanarayana Birudukota, Marcus Miethke, Nanaji Arisetti, and HZI,Helmholtz-Zentrum für Infektionsforschung GmbH, Inhoffenstr. 7,38124 Braunschweig, Germany.
- Subjects
medicine.drug_class ,Tetracycline ,Antibiotics ,Microbial Sensitivity Tests ,Gram-Positive Bacteria ,01 natural sciences ,Natural product ,Acylation ,Structure-Activity Relationship ,03 medical and health sciences ,chemistry.chemical_compound ,Electrophilic substitution ,Antibiotic resistance ,Drug Discovery ,medicine ,Semisynthesis ,030304 developmental biology ,Pharmacology ,0303 health sciences ,Dose-Response Relationship, Drug ,Molecular Structure ,010405 organic chemistry ,Organic Chemistry ,General Medicine ,Combinatorial chemistry ,Anti-Bacterial Agents ,0104 chemical sciences ,chemistry ,Tetracyclines ,Gram-negative bacteria ,Chelocardin ,Antibacterial activity ,medicine.drug - Abstract
To address the global challenge of emerging antimicrobial resistance, the hitherto most successful strategy to new antibiotics has been the optimization of validated natural products; most of these efforts rely on semisynthesis. Herein, we report the semisynthetic modification of amidochelocardin, an atypical tetracycline obtained via genetic engineering of the chelocardin producer strain. We report modifications at C4, C7, C10 and C11 by the application of methylation, acylation, electrophilic substitution, and oxidative C-C coupling reactions. The antibacterial activity of the reaction products was tested against a panel of Gram-positive and Gram-negative pathogens. The emerging structure-activity relationships (SARs) revealed that positions C7 and C10 are favorable anchor points for the semisynthesis of optimized derivatives. The observed SAR was different from that known for tetracyclines, which underlines the pronounced differences between the two compound classes.
- Published
- 2023
- Full Text
- View/download PDF
31. Scientific opinion on the tolerable upper intake level for selenium
- Author
-
Turck, Dominique, Bohn, Torsten, Castenmiller, Jacqueline, De Henauw, Stefaan, Hirsch-Ernst, Karen-Ildico, Knutsen, Helle Katrine, Maciuk, Alexandre, Mangelsdorf, Inge, McArdle, Harry J., Pelaez, Carmen, Pentieva, Kristina, Siani, Alfonso, Thies, Frank, Tsabouri, Sophia, Vinceti, Marco, Aggett, Peter, Crous Bou, Marta, Cubadda, Francesco, Ciccolallo, Laura, de Sesmaisons Lecarre, Agnes, Fabiani, Lucia, Titz, Ariane, and Naska, Androniki
- Subjects
PROSTATE-CANCER RISK ,dietary reference value ,UL ,Veterinary (miscellaneous) ,Plant Science ,POLYCYSTIC-OVARY-SYNDROME ,CONTROLLED-TRIAL ,Microbiology ,RANDOMIZED ,tolerable upper intake level ,Chemistry ,Medicine and Health Sciences ,PLASMA SELENIUM ,SERUM SELENIUM ,CORONARY-HEART-DISEASE ,Animal Science and Zoology ,Parasitology ,GLUTATHIONE-PEROXIDASE ACTIVITY ,DIETARY SELENIUM ,selenium ,TOENAIL SELENIUM ,SELENOPROTEIN-P ,Food Science - Abstract
Following a request from the European Commission, the EFSA Panel on Nutrition, Novel Foods and Food Allergens (NDA) was asked to deliver a scientific opinion on the tolerable upper intake level (UL) for selenium. Systematic reviews of the literature were conducted to identify evidence regarding excess selenium intake and clinical effects and potential biomarkers of effect, risk of chronic diseases and impaired neuropsychological development in humans. Alopecia, as an early observable feature and a well-established adverse effect of excess selenium exposure, is selected as the critical endpoint on which to base a UL for selenium. A lowest-observed-adverse-effect-level (LOAEL) of 330 mu g/day is identified from a large randomised controlled trial in humans (the Selenium and Vitamin E Cancer Prevention Trial (SELECT)), to which an uncertainty factor of 1.3 is applied. A UL of 255 mu g/day is established for adult men and women (including pregnant and lactating women). ULs for children are derived from the UL for adults using allometric scaling (body weight(0.75)). Based on available intake data, adult consumers are unlikely to exceed the UL, except for regular users of food supplements containing high daily doses of selenium or regular consumers of Brazil nuts. No risk has been reported with the current levels of selenium intake in European countries from food (excluding food supplements) in toddlers and children, and selenium intake arising from the natural content of foods does not raise reasons for concern. Selenium-containing supplements in toddlers and children should be used with caution, based on individual needs.
- Published
- 2023
32. Safety of 6′‐sialyllactose (6’‐SL) sodium salt produced by derivative strains of Escherichia coli BL21 (DE3) as a novel food pursuant to Regulation (EU) 2015/2283
- Author
-
Turck, Dominique, Bohn, Torsten, Castenmiller, Jacqueline, De Henauw, Stefaan, Hirsch-Ernst, Karen Ildico, Maciuk, Alexandre, Mangelsdorf, Inge, McArdle, Harry J., Naska, Androniki, Pelaez, Carmen, Pentieva, Kristina, Siani, Alfonso, Thies, Frank, Tsabouri, Sophia, Vinceti, Marco, Cubadda, Francesco, Frenzel, Thomas, Heinonen, Marina, Marchelli, Rosangela, Neuhauser-Berthold, Monika, Poulsen, Morten, Maradona, Miguel Prieto, Schlatter, Josef Rudolf, van Loveren, Henk, Colombo, Paolo, Fernandez, Estefania Noriega, Knutsen, Helle Katrine, and Nutr Novel Foods Food A, EFSA Panel
- Subjects
Agriculture and Food Sciences ,safety ,6’-SL sodium salt ,6′-sialyllactose ,HiMO ,HMO ,human milk oligosaccharide ,novel food ,HUMAN-MILK OLIGOSACCHARIDES ,Veterinary (miscellaneous) ,INFANTS ,PREBIOTICS ,Plant Science ,BIFIDOBACTERIA ,Microbiology ,REVEALS ,FORMULA ,GUT MICROBIOTA ,6'-SL sodium salt ,PROBIOTICS ,Chemistry ,Animal Science and Zoology ,Parasitology ,6'-sialyllactose ,PRECIPITATE ,LACTOSE ,Food Science - Abstract
Following a request from the European Commission, the EFSA Panel on Nutrition, Novel Foods and Food Allergens (NDA) was asked to deliver an opinion on 6'-sialyllactose (6'-SL) sodium salt as a novel food (NF) pursuant to Regulation (EU) 2015/2283. The NF is mainly composed of the human-identical milk oligosaccharide (HiMO) 6'-SL, but it also contains d-lactose, 6'-sialyllactulose, sialic acid, N-acetyl-d-glucosamine and a small fraction of other related oligosaccharides. The NF is produced by fermentation with two genetically modified strains of Escherichia coli BL21 (DE3), the production strain and the optional degradation strain. The information provided on the identity, manufacturing process, composition and specifications of the NF does not raise safety concerns. The applicant intends to add the NF to a variety of foods, including infant formula and follow-on formula, food for special medical purposes and food supplements. The target population is the general population. In some scenarios at the maximum use levels, the estimated intakes per kg body weight were higher than the high average natural intake of 6'-SL from human milk. However, given the intrinsic nature of human milk oligosaccharides (HMOs), the wide range of intakes from human milk, and considering that infants are naturally exposed to similar amounts of these substances, the Panel considers that the consumption of the NF at the proposed conditions of use does not raise safety concerns. The intake of 6'-SL in breastfed infants on a body weight basis is also expected to be safe for other population groups. The intake of other carbohydrate-type compounds structurally related to 6'-SL is also considered of no safety concern. Food supplements are not intended to be used if other foods with added 6'-SL or human milk are consumed on the same day. The Panel concludes that the NF is safe under the proposed conditions of use. (C) 2022 Wiley-VCH Verlag GmbH & Co. KgaA on behalf of the European Food Safety Authority.
- Published
- 2022
33. The Influence of Ski Waist-Width and Fatigue on Knee-Joint Stability and Skier’s Balance
- Author
-
Martin Zorko, Karmen Hirsch, Nejc Šarabon, and Matej Supej
- Subjects
skiing simulation ,optical motion capture ,tensiometer ,ski waist-width ,balance ,knee injury ,Technology ,Engineering (General). Civil engineering (General) ,TA1-2040 ,Biology (General) ,QH301-705.5 ,Physics ,QC1-999 ,Chemistry ,QD1-999 - Abstract
Alpine skiing is a complex sport that demands a high level of motor control and balance. In general, skiers are prone to deterioration in the state of fatigue due to using inappropriate equipment. As a consequence, the risk of injury might increase. This study aimed to examine the influence of fatigue and ski waist-width on knee-joint stability and skier’s balance. A laboratory skiing simulation in a quasistatic ski-turning position was conducted where the lower-limb kinematics was recorded using an optical system, and the balance-determining parameters were captured using a force plate. It was demonstrated that the knee-joint kinematics and skier’s balance were hampered in the state of fatigue, as well as when using skis with a large waist-width. The results of the study suggest avoiding the fatigue state and the use of skis having a large waist-width while skiing on hard surfaces to decrease the risk of injury.
- Published
- 2020
- Full Text
- View/download PDF
34. Custom-Made Horizontal and Vertical Maxillary Augmentation with Smartbone® On Demand™: A Seven-Year Follow-Up Case
- Author
-
Elias Messo, Carlo F. Grottoli, Giuseppe Perale, and Jan-Michaél Hirsch
- Subjects
bone substitute ,SmartBone On Demand ,custom implants ,bone regeneration ,xeno-hybrid bone graft ,Technology ,Engineering (General). Civil engineering (General) ,TA1-2040 ,Biology (General) ,QH301-705.5 ,Physics ,QC1-999 ,Chemistry ,QD1-999 - Abstract
The presence of non-sufficient bone height and width requires an increase in the amount of bone available to insert an implant. Different materials are described in the literature, and the “custom-made bone graft approach” is a modern option which currently requires a preoperative stage of studying the bone defect and designing the implant. SmartBone® (SB®) mimics the characteristics of healthy human bone. Thanks to the strong performance, high workability, resistance and shape retention of SB®, it is possible to obtain SmartBone® on DemandTM, a bone graft uniquely shaped exactly to patient specifications, produced by following the data precisely and contoured to the bone defect site. The aim of this study was to determine the success over 7 years following a customized SmartBone® on DemandTM, a xeno-hybrid bone graft and installation of implants in a maxillary horizontal and vertical atrophy. This case study presents the diagnosis for a 60-year-old male patient requesting the rehabilitation of his edentulous maxilla with dental implants. Preoperative evaluation included the study of photographs, a radiological examination and 3D reconstruction to assess the missing bone, implant size, positioning of implants and anatomical landmarks. Rehabilitation included the insertion of a custom-made xeno-hybrid bone block into the maxilla in order to restore the anatomy prior to the implants’ placement. The newly developed bone substitute SB® is a safe and effective material, and its custom-made variant SmartBone® on DemandTM has been shown to be a valid alternative to traditional autologous bone grafting techniques in terms of accuracy, absence of infection/rejection and overall clinical outcome.
- Published
- 2020
- Full Text
- View/download PDF
35. Gold Nanoparticles Radio-Sensitize and Reduce Cell Survival in Lewis Lung Carcinoma
- Author
-
Arvind Pandey, Veronica Vighetto, Nicola Di Marzio, Francesca Ferraro, Matteo Hirsch, Nicola Ferrante, Sankar Mitra, Alessandro Grattoni, and Carly S. Filgueira
- Subjects
gold nanoparticles ,Lewis lung carcinoma ,radio-sensitization ,clonogenic assay ,comet assay ,Chemistry ,QD1-999 - Abstract
It has been suggested that particle size plays an important role in determining the genotoxicity of gold nanoparticles (GNPs). The purpose of this study was to compare the potential radio-sensitization effects of two different sized GNPs (3.9 and 37.4 nm) fabricated and examined in vitro in Lewis lung carcinoma (LLC) as a model of non-small cell lung cancer through use of comet and clonogenic assays. After treatment with 2Gy X-ray irradiation, both particle sizes demonstrated increased DNA damage when compared to treatment with particles only and radiation alone. This radio-sensitization was further translated into a reduction in cell survival demonstrated by clonogenicity. This work indicates that GNPs of both sizes induce DNA damage in LLC cells at the tested concentrations, whereas the 37.4 nm particle size treatment group demonstrated greater significance in vitro. The presented data aids in the evaluation of the radiobiological response of Lewis lung carcinoma cells treated with gold nanoparticles.
- Published
- 2020
- Full Text
- View/download PDF
36. Unraveling the stepwise maturation of the yeast telomerase including a Cse1 and Mtr10 mediated quality control checkpoint
- Author
-
Anna Greta Hirsch, Daniel Becker, Jan-Philipp Lamping, and Heike Krebber
- Subjects
Telomerase ,Cytoplasm ,Nucleocytoplasmic Transport Proteins ,Saccharomyces cerevisiae Proteins ,Science ,Saccharomyces cerevisiae ,Active Transport, Cell Nucleus ,RNA transport ,medicine.disease_cause ,Senescence ,Models, Biological ,Article ,Gene Expression Regulation, Fungal ,medicine ,Karyopherin ,chemistry.chemical_classification ,Mutation ,Multidisciplinary ,biology ,RNA quality control ,RNA ,RNA-Binding Proteins ,biology.organism_classification ,Cell biology ,Telomere ,chemistry ,Nuclear transport ,Medicine ,Protein Binding - Abstract
Telomerases elongate the ends of chromosomes required for cell immortality through their reverse transcriptase activity. By using the model organism Saccharomyces cerevisiae we defined the order in which the holoenzyme matures. First, a longer precursor of the telomerase RNA, TLC1 is transcribed and exported into the cytoplasm, where it associates with the protecting Sm-ring, the Est and the Pop proteins. This partly matured telomerase is re-imported into the nucleus via Mtr10 and a novel TLC1-import factor, the karyopherin Cse1. Remarkably, while mutations in all known transport factors result in short telomere ends, mutation in CSE1 leads to the amplification of Y′ elements in the terminal chromosome regions and thus elongated telomere ends. Cse1 does not only support TLC1 import, but also the Sm-ring stabilization on the RNA enableling Mtr10 contact and nuclear import. Thus, Sm-ring formation and import factor contact resembles a quality control step in the maturation process of the telomerase. The re-imported immature TLC1 is finally trimmed into the 1158 nucleotides long mature form via the nuclear exosome. TMG-capping of TLC1 finalizes maturation, leading to mature telomerase.
- Published
- 2021
37. Dual expression and anatomy lines allow simultaneous visualization of gene expression and anatomy
- Author
-
Darren M. Wells, George Janes, Alexander Ware, Nicola Leftley, Paul T. Tarr, Anthony Bishopp, Kevin A. Pyke, Britta M. C. Kümpers, Jingyi Han, Nicholas Redman, John Vaughan-Hirsch, Jonathan A. Atkinson, Ute Voß, and Giuseppe Castiglione
- Subjects
AcademicSubjects/SCI01280 ,Physiology ,Arabidopsis ,Cloning vector ,Organogenesis ,ORGANIZATION ,Plant Science ,Biology ,Genes, Plant ,Plant Roots ,INITIATION ,Plant Growth Regulators ,Gene Expression Regulation, Plant ,Genes, Reporter ,Auxin ,Gene expression ,Genetics ,Arabidopsis thaliana ,Gene ,Ultrasonography ,chemistry.chemical_classification ,AcademicSubjects/SCI01270 ,Science & Technology ,AcademicSubjects/SCI02288 ,AcademicSubjects/SCI02287 ,Cell Membrane ,AcademicSubjects/SCI02286 ,Plant Sciences ,fungi ,Lateral root ,food and beverages ,Anatomy ,Genes, Development and Evolution ,ARABIDOPSIS ,biology.organism_classification ,DIFFERENTIATION ,chemistry ,CELLS ,Breakthrough Technologies, Tools, and Resources ,Life Sciences & Biomedicine - Abstract
Studying the developmental genetics of plant organs requires following gene expression in specific tissues. To facilitate this, we have developed dual expression anatomy lines, which incorporate a red plasma membrane marker alongside a fluorescent reporter for a gene of interest in the same vector. Here, we adapted the GreenGate cloning vectors to create two destination vectors showing strong marking of cell membranes in either the whole root or specifically in the lateral roots. This system can also be used in both embryos and whole seedlings. As proof of concept, we follow both gene expression and anatomy in Arabidopsis (Arabidopsis thaliana) during lateral root organogenesis for a period of over 24 h. Coupled with the development of a flow cell and perfusion system, we follow changes in activity of the DII auxin sensor following application of auxin., A vector system and flow cell set-up allow long-term imaging of both gene expression and anatomy in Arabidopsis primary and lateral roots.
- Published
- 2021
38. Carbon Nano-onions: Potassium Intercalation and Reductive Covalent Functionalization
- Author
-
Frank Hauke, Claudia Kröckel, Andreas Hirsch, Manuel Melle-Franco, Edison Castro, Luis Echegoyen, Julio C. Chacón-Torres, Katharina Werbach, Matteo Andrea Lucherelli, Gonzalo Abellán, Jani Kotakoski, Ursula Ludacka, M. Eugenia Pérez-Ojeda, and Herwig Peterlik
- Subjects
Thermogravimetric analysis ,Iodide ,Intercalation (chemistry) ,02 engineering and technology ,010402 general chemistry ,Photochemistry ,01 natural sciences ,7. Clean energy ,Biochemistry ,Article ,Catalysis ,symbols.namesake ,Colloid and Surface Chemistry ,Nucleophilic substitution ,chemistry.chemical_classification ,Electron energy loss spectroscopy ,technology, industry, and agriculture ,General Chemistry ,021001 nanoscience & nanotechnology ,Espectroscòpia Raman ,0104 chemical sciences ,chemistry ,Covalent bond ,symbols ,Surface modification ,Materials nanoestructurats ,0210 nano-technology ,Raman spectroscopy - Abstract
Herein we report the synthesis of covalently functionalized carbon nano-onions (CNOs) via a reductive approach using unprecedented alkali-metal CNO intercalation compounds. For the first time, an in situ Raman study of the controlled intercalation process with potassium has been carried out revealing a Fano resonance in highly doped CNOs. The intercalation was further confirmed by electron energy loss spectroscopy and X-ray diffraction. Moreover, the experimental results have been rationalized with DFT calculations. Covalently functionalized CNO derivatives were synthesized by using phenyl iodide and n-hexyl iodide as electrophiles in model nucleophilic substitution reactions. The functionalized CNOs were exhaustively characterized by statistical Raman spectroscopy, thermogravimetric analysis coupled with gas chromatography and mass spectrometry, dynamic light scattering, UV-vis, and ATR-FTIR spectroscopies. This work provides important insights into the understanding of the basic principles of reductive CNOs functionalization and will pave the way for the use of CNOs in a wide range of potential applications, such as energy storage, photovoltaics, or molecular electronics.
- Published
- 2021
39. Diastereoselective formation of homochiral flexible perylene bisimide cyclophanes and their hybrids with fullerenes†‡
- Author
-
Edurne Nuin, M. Eugenia Pérez-Ojeda, Dirk M. Guldi, Barbara Scholz, Swathi Krishna, Andreas Hirsch, Harald Maid, and Iris Solymosi
- Subjects
Fullerene ,010405 organic chemistry ,Stacking ,Diastereomer ,General Chemistry ,010402 general chemistry ,Ring (chemistry) ,01 natural sciences ,0104 chemical sciences ,Crystallography ,chemistry.chemical_compound ,Chemistry ,chemistry ,Proton NMR ,Selectivity ,Chirality (chemistry) ,Perylene - Abstract
Cyclophanes of different ring sizes featuring perylene-3,4:9,10-tetracarboxylic acid bisimide (PBI) linked by flexible malonates were designed, synthesized, and investigated with respect to their structural, chemical and photo-physical properties. It is predominantly the number of PBIs and their geometric arrangement, which influence dramatically their properties. For example, two-PBI containing cyclophanes reveal physico-chemical characteristics that are governed by strong co-facial π–π interactions. This is in stark contrast to cyclophanes with either three or four PBIs. Key to co-facial π–π stackings are the flexible malonate linkers, which, in turn, set up the ways and means for diastereoselectivity of the homochiral PBIs at low temperatures, on one hand. In terms of selectivity, diastereomeric (M,M)/(P,P) : (M,P)/(P,M) pairs with a ratio of approximately 10 : 1 are discernible in the 1H NMR spectra in C2D2Cl4 and a complete diastereomeric excess is found in CD2Cl2. On the other hand, symmetry-breaking charge transfer as well as charge separation at room temperature are corroborated in steady-state and time-resolved photo-physical investigations. Less favourable are co-facial π–π stackings in the three-PBI containing cyclophanes. For statistical reasons, the diastereoisomers (M,M,M)/(P,P,P) and (M,M,P)/(P,P,M) occur here in a ratio of 1 : 3. In this case, symmetry-breaking charge transfer as well as charge separation are both slowed down. The work was rounded-off by integrating next to the PBIs, for the first time, hydrophobic or hydrophilic fullerenes into the resulting cyclophanes. Our novel fullerene–PBI cyclophanes reveal unprecedented diastereoselective formation of homochiral (M,M)/(P,P) pairs exceeding the traditional host–guest approach. Hybridization with fullerenes allows us to modulate the resulting solubility, stacking, cavity and chirality, which is of tremendous interest in the field., Perylene bisimide (PBI) cyclophanes linked by flexible malonates were functionalized with fullerenes. Modulation of the chemical environment enhances the chiral self-sorting, leading exclusively to the homochiral diastereomeric pair (M,M)/(P,P).
- Published
- 2021
40. Tunable Photoswitching in Norbornadiene (NBD)/Quadricyclane (QC) – Fullerene Hybrids
- Author
-
Patrick Lorenz, Bernd Meyer, Andreas Hirsch, Antonia Rüter, and Florian Wullschläger
- Subjects
Molecular switch ,energy conversion ,Fullerene ,Full Paper ,photoswitch ,Photoswitch ,Norbornadiene ,Organic Chemistry ,Prato reaction ,fullerenes ,General Chemistry ,Full Papers ,Combinatorial chemistry ,Catalysis ,chemistry.chemical_compound ,chemistry ,ddc:540 ,norbornadiene ,Moiety ,Quadricyclane ,molecular switches ,Linker - Abstract
With respect to molecular switches, initializing the quadricyclane (QC) to norbornadiene (NBD) back‐reaction by light is highly desirable. Our previous publication provided a unique solution for this purpose by utilizing covalently bound C60. In this work, the fundamental processes within these hybrids has been investigated. Variation of the linker unit connecting the NBD/QC moiety with the fullerene core is used as a tool to tune the properties of the resulting hybrids. Utilizing the Prato reaction, two unprecedented NBD/QC – fullerene hybrids having a long‐rigid and a short‐rigid linker were synthesized. Molecular dynamics simulations revealed that this results in an average QC–C60 distance of up to 14.2 Å. By comparing the NBD–QC switching of these derivatives with the already established one having a flexible linker, valuable mechanistic insights were gained. Most importantly, spatial convergence of the QC moiety and the fullerene core is inevitable for an efficient back‐reaction., Spatial distance has a major impact on the photoswitching in NBD/QC – fullerene hybrids. By careful molecular design and using MD simulations it was possible to gain valuable insight into the mechanism underlying these unique photoswitches.
- Published
- 2021
41. Myeloid malignancies with translocation t(4;12)(q11‐13;p13): molecular landscape, clonal hierarchy and clinical outcomes
- Author
-
François Lifermann, Jean-Alain Martignoles, Anne Quinquenel, Vincent Parinet, Christine Lefebvre, Pierre Hirsch, Mélanie Martin, Sabine Defasque, Florence Nguyen-Khac, Matthieu Decamp, Laurence Simon, Dominique Penther, Nadia Ali-Ammar, Elise Chapiro, Odile Maarek, Chrystele Bilhou-Nabera, Baptiste Gaillard, Agathe Maillon, Jean-Baptiste Micol, Marine Baron, Nathalie Auger, Stéphanie Struski, Damien Roos-Weil, Sylvie Tondeur, Marie-Joelle Mozziconacci, Audrey Bidet, Service d'Hématologie clinique [CHU Pitié-Salpêtrière], CHU Pitié-Salpêtrière [AP-HP], Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-Sorbonne Université (SU)-Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-Sorbonne Université (SU), Service de Génétique Cytogénétique et Embryologie [CHU Pitié-Salpêtrière], Centre de Recherche des Cordeliers (CRC (UMR_S_1138 / U1138)), École pratique des hautes études (EPHE), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Sorbonne Université (SU)-Université de Paris (UP), Hôpital Haut-Lévêque [CHU Bordeaux], CHU Bordeaux [Bordeaux], Hôpital Robert Debré, Service d'Hémato-oncologie [CHU Saint-Louis], Groupe Hospitalier Saint Louis - Lariboisière - Fernand Widal [Paris], Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP), Centre Hospitalier Universitaire [Grenoble] (CHU), Laboratoire CERBA [Saint Ouen l'Aumône], Institut Paoli-Calmettes, Fédération nationale des Centres de lutte contre le Cancer (FNCLCC), Centre Hospitalier Universitaire de Reims (CHU Reims), Service de Génétique [CHU Caen], CHU Caen, Normandie Université (NU)-Tumorothèque de Caen Basse-Normandie (TCBN)-Normandie Université (NU)-Tumorothèque de Caen Basse-Normandie (TCBN)-Université de Caen Normandie (UNICAEN), Normandie Université (NU), Centre Hospitalier de Dax, Hôpital Universitaire Carémeau [Nîmes] (CHU Nîmes), Centre Hospitalier Universitaire de Nîmes (CHU Nîmes), Institut Universitaire du Cancer de Toulouse - Oncopole (IUCT Oncopole - UMR 1037), Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-CHU Toulouse [Toulouse]-Institut National de la Santé et de la Recherche Médicale (INSERM), Génomique et Médecine Personnalisée du Cancer et des Maladies Neuropsychiatriques (GPMCND), Université de Rouen Normandie (UNIROUEN), Normandie Université (NU)-Normandie Université (NU)-Institut National de la Santé et de la Recherche Médicale (INSERM), Département d'hématologie [Gustave Roussy], Institut Gustave Roussy (IGR), Génétique (Biologie pathologie), Département de biologie et pathologie médicales [Gustave Roussy], Institut Gustave Roussy (IGR)-Institut Gustave Roussy (IGR), CHU Saint-Antoine [AP-HP], Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-Sorbonne Université (SU), Centre de Recherche Saint-Antoine (CR Saint-Antoine), Sorbonne Université (SU)-Institut National de la Santé et de la Recherche Médicale (INSERM)-CHU Saint-Antoine [AP-HP], Service d'immunologie et hématologies biologiques [CHU Saint-Antoine], Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Sorbonne Université (SU)-Université Paris Cité (UPCité), Centre de Recherche en Cancérologie de Marseille (CRCM), Aix Marseille Université (AMU)-Institut Paoli-Calmettes, Fédération nationale des Centres de lutte contre le Cancer (FNCLCC)-Fédération nationale des Centres de lutte contre le Cancer (FNCLCC)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS), Université de Caen Normandie (UNICAEN), Normandie Université (NU)-Normandie Université (NU)-CHU Caen, Normandie Université (NU)-Tumorothèque de Caen Basse-Normandie (TCBN)-Tumorothèque de Caen Basse-Normandie (TCBN), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre Hospitalier Universitaire de Toulouse (CHU Toulouse)-Institut National de la Santé et de la Recherche Médicale (INSERM), Centre de Recherche Saint-Antoine (CRSA), Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Sorbonne Université (SU), HAL-SU, Gestionnaire, École Pratique des Hautes Études (EPHE), and Université de Toulouse (UT)-Université de Toulouse (UT)-Centre Hospitalier Universitaire de Toulouse (CHU Toulouse)-Institut National de la Santé et de la Recherche Médicale (INSERM)
- Subjects
Male ,Oncology ,Myeloid ,[SDV]Life Sciences [q-bio] ,Chromosomal translocation ,Translocation, Genetic ,chemistry.chemical_compound ,0302 clinical medicine ,hemic and lymphatic diseases ,12) ,In Situ Hybridization, Fluorescence ,Aged, 80 and over ,CHIC2 ,Middle Aged ,Immunohistochemistry ,3. Good health ,[SDV] Life Sciences [q-bio] ,Leukemia, Myeloid, Acute ,medicine.anatomical_structure ,RUNX1 ,030220 oncology & carcinogenesis ,Cytogenetic Analysis ,Cohort ,Molecular Medicine ,Female ,Original Article ,Chromosomes, Human, Pair 4 ,medicine.medical_specialty ,IDH1 ,03 medical and health sciences ,Internal medicine ,Biomarkers, Tumor ,medicine ,Humans ,Genetic Predisposition to Disease ,acute myeloid leukaemia ,Genetic Association Studies ,Aged ,Chromosome Aberrations ,Chromosomes, Human, Pair 12 ,Myeloproliferative Disorders ,business.industry ,Myelodysplastic syndromes ,Original Articles ,ETV6 ,Cell Biology ,medicine.disease ,myelodysplastic syndrome ,t(4 ,chemistry ,Fusion transcript ,Myelodysplastic Syndromes ,prognosis ,business ,030215 immunology - Abstract
International audience; Translocation t(4;12)(q11-13;p13) is a recurrent but very rare chromosomal aberration in acute myeloid leukaemia (AML) resulting in the non-constant expression of a CHIC2/ETV6 fusion transcript. We report clinico-biological features, molecular characteristics and outcomes of 21 cases of t(4;12) including 19 AML and two myelodysplastic syndromes (MDS). Median age at the time of t(4;12) was 78 years (range, 56–88). Multilineage dysplasia was described in 10 of 19 (53%) AML cases and CD7 and/or CD56 expression in 90%. FISH analyses identified ETV6 and CHIC2 region rearrangements in respectively 18 of 18 and 15 of 17 studied cases. The t(4;12) was the sole cytogenetic abnormality in 48% of cases. The most frequent associated mutated genes were ASXL1 (n = 8/16, 50%), IDH1/2 (n = 7/16, 44%), SRSF2 (n = 5/16, 31%) and RUNX1 (n = 4/16, 25%). Interestingly, concurrent FISH and molecular analyses showed that t(4;12) can be, but not always, a founding oncogenic event. Median OS was 7.8 months for the entire cohort. In the 16 of 21 patients (76%) who received antitumoral treatment, overall response and first complete remission rates were 37% and 31%, respectively. Median progression-free survival in responders was 13.7 months. Finally, t(4;12) cases harboured many characteristics of AML with myelodysplasia-related changes (multilineage dysplasia, MDS-related cytogenetic abnormalities, frequent ASXL1 mutations) and a poor prognosis.
- Published
- 2021
42. Tumor-Derived Prostaglandin E2 Promotes p50 NF-κB-Dependent Differentiation of Monocytic MDSCs
- Author
-
Viviana Piccolo, Augusto Bleve, Renato Ostuni, Sara Morlacchi, Monica Rimoldi, Chiara Porta, Silvia Tartari, Mario P. Colombo, Alessandro Ippolito, Mariangela Storto, Giulia Soldà, Paola Larghi, Sabina Sangaletti, Stefano Duga, Claudio Tripodo, Tiziana Pressiani, Gioacchino Natoli, Lorenza Rimassa, Laura Strauss, Antonio Sica, Emilio Hirsch, Andrea Doni, Vincenzo Bronte, Stefania Banfi, Fiorella Balzac, Francesca Maria Consonni, Maria Grazia Totaro, Emilia Turco, Porta, Chiara, Consonni, Francesca Maria, Morlacchi, Sara, Sangaletti, Sabina, Bleve, Augusto, Totaro, Maria Grazia, Larghi, Paola, Rimoldi, Monica, Tripodo, Claudio, Strauss, Laura, Banfi, Stefania, Storto, Mariangela, Pressiani, Tiziana, Rimassa, Lorenza, Tartari, Silvia, Ippolito, Alessandro, Doni, Andrea, Soldà, Giulia, Duga, Stefano, Piccolo, Viviana, Ostuni, Renato, Natoli, Gioacchino, Bronte, Vincenzo, Balzac, Fiorella, Turco, Emilia, Hirsch, Emilio, Colombo, Mario P, and Sica, Antonio
- Subjects
0301 basic medicine ,Cancer Research ,Cellular differentiation ,Prostaglandin E2 receptor ,medicine.medical_treatment ,Melanoma, Experimental ,Apoptosis ,Settore MED/08 - Anatomia Patologica ,Nitric Oxide ,Dinoprostone ,Monocytes ,Interferon-gamma ,Mice ,03 medical and health sciences ,0302 clinical medicine ,Immune system ,Oxytocics ,Immune Tolerance ,Tumor Cells, Cultured ,medicine ,Animals ,Humans ,Prostaglandin E2 ,Cell Proliferation ,Chemistry ,Myeloid-Derived Suppressor Cells ,NF-kappa B p50 Subunit ,Cell Differentiation ,Immunotherapy ,Acquired immune system ,Pancreatic Neoplasms ,030104 developmental biology ,Oncology ,p50 NF-κB, differentiation of monocytic , MDSC ,030220 oncology & carcinogenesis ,Myeloid-derived Suppressor Cell ,Cancer research ,Tumor necrosis factor alpha ,Colorectal Neoplasms ,medicine.drug - Abstract
Myeloid-derived suppressor cells (MDSC) include immature monocytic (M-MDSC) and granulocytic (PMN-MDSC) cells that share the ability to suppress adaptive immunity and to hinder the effectiveness of anticancer treatments. Of note, in response to IFNγ, M-MDSCs release the tumor-promoting and immunosuppressive molecule nitric oxide (NO), whereas macrophages largely express antitumor properties. Investigating these opposing activities, we found that tumor-derived prostaglandin E2 (PGE2) induces nuclear accumulation of p50 NF-κB in M-MDSCs, diverting their response to IFNγ toward NO-mediated immunosuppression and reducing TNFα expression. At the genome level, p50 NF-κB promoted binding of STAT1 to regulatory regions of selected IFNγ-dependent genes, including inducible nitric oxide synthase (Nos2). In agreement, ablation of p50 as well as pharmacologic inhibition of either the PGE2 receptor EP2 or NO production reprogrammed M-MDSCs toward a NOS2low/TNFαhigh phenotype, restoring the in vivo antitumor activity of IFNγ. Our results indicate that inhibition of the PGE2/p50/NO axis prevents MDSC-suppressive functions and restores the efficacy of anticancer immunotherapy. Significance: Tumor-derived PGE2-mediated induction of nuclear p50 NF-κB epigenetically reprograms the response of monocytic cells to IFNγ toward an immunosuppressive phenotype, thus retrieving the anticancer properties of IFNγ.
- Published
- 2020
43. Effects of Formate Binding to a Bipyridine-Based Cobalt-4N Complex
- Author
-
J. Mathias Weber, Rebecca J. Hirsch, and Madison M. Foreman
- Subjects
Ligand ,Infrared ,chemistry.chemical_element ,Redox ,Quantitative Biology::Subcellular Processes ,Metal ,Bipyridine ,chemistry.chemical_compound ,Crystallography ,chemistry ,visual_art ,visual_art.visual_art_medium ,Density functional theory ,Formate ,Physical and Theoretical Chemistry ,Cobalt - Abstract
We report the vibrational spectrum of a metal-organic complex consisting of a Co center surrounded by two bipyridine-based ligands and explore the change of the spectrum upon addition of a formate ligand to the complex. We assign the spectra using density functional theory. The infrared response encodes the binding motif of the formate to the metal, and the calculated charge distributions highlight the ability of the organic ligand framework to act as charge reservoirs modulating the redox properties of the metal center.
- Published
- 2021
44. Mycosis fungoides‐derived exosomes promote cell motility and are enriched with microRNA‐155 and microRNA‐1246, and their plasma‐cell‐free expression may serve as a potential biomarker for disease burden
- Author
-
Iris Amitay-Laish, E. Hodak, C Querfeld, Lilach Moyal, Jasmine Jacob-Hirsch, B. Gorovitz‐Haris, C Arkin, Steven T. Rosen, Jamal Knaneh, and H Prag-Naveh
- Subjects
Skin Neoplasms ,Chemistry ,Cell migration ,Dermatology ,Plasma cell ,Exosomes ,Exosome ,Microvesicles ,miR-155 ,MicroRNAs ,Mycosis Fungoides ,medicine.anatomical_structure ,Real-time polymerase chain reaction ,Cell Movement ,microRNA ,Biomarkers, Tumor ,Cancer research ,medicine ,Humans ,Immunostaining - Abstract
BACKGROUND Literature regarding exosomes as mediators in intercellular communication to promote progression in mycosis fungoides (MF) is lacking. OBJECTIVES To characterize MF-derived exosomes and their involvement in the disease. METHODS Exosomes were isolated by ultracentrifugation from cutaneous T-cell lymphoma (CTCL) cell lines, and from plasma of patients with MF and controls (healthy individuals). Exosomes were confirmed by electron microscopy, NanoSight and CD81 staining. Cell-line exosomes were profiled for microRNA array. Exosomal microRNA (exomiRNA) expression and uptake, and plasma-cell-free microRNA (cfmiRNA) were analysed by reverse-transcriptase quantitative polymerase chain reaction. Exosome uptake was monitored by fluorescent labelling and CD81 immunostaining. Migration was analysed by transwell migration assay. RESULTS MyLa- and MJ-derived exosomes had a distinctive microRNA signature with abundant microRNA (miR)-155 and miR-1246. Both microRNAs were delivered into target cells, but only exomiR-155 was tested, demonstrating a migratory effect on target cells. Plasma levels of cfmiR-1246 were significantly highest in combined plaque/tumour MF, followed by patch MF, and were lowest in controls (plaque/tumour > patch > healthy), while cfmiR-155 was upregulated only in plaque/tumour MF vs. controls. Specifically, exomiR-1246 (and not exomiR-155) was higher in plasma of plaque/tumour MF than in healthy controls. Plasma exosomes from MF but not from controls increased cell migration. CONCLUSIONS Our findings show that MF-derived exosomes promote cell motility and are enriched with miR-155, a well-known microRNA in MF, and miR-1246, not previously reported in MF. Based on their plasma expression we suggest that they may serve as potential biomarkers for tumour burden.
- Published
- 2021
45. New insights into the role of glycosaminoglycans in the endosteal bone microenvironment
- Author
-
Juliane Salbach-Hirsch, Lorenz C. Hofbauer, Martina Rauner, and Christine Hofbauer
- Subjects
0301 basic medicine ,Clinical Biochemistry ,Matrix (biology) ,Biochemistry ,Bone remodeling ,Extracellular matrix ,03 medical and health sciences ,0302 clinical medicine ,Humans ,Stem Cell Niche ,Wnt Signaling Pathway ,Molecular Biology ,Glycosaminoglycans ,biology ,Chemistry ,Mesenchymal stem cell ,Wnt signaling pathway ,Extracellular Matrix ,Cell biology ,Haematopoiesis ,030104 developmental biology ,RANKL ,030220 oncology & carcinogenesis ,biology.protein ,Bone Remodeling ,Signal transduction - Abstract
The bone microenvironment is a complex tissue in which heterogeneous cell populations of hematopoietic and mesenchymal origin interact with environmental cues to maintain tissue integrity. Both cellular and matrix components are subject to physiologic challenges and can dynamically respond by modifying cell/matrix interactions. When either component is impaired, the physiologic balance is lost. Here, we review the current state of knowledge of how glycosaminoglycans – organic components of the bone extracellular matrix – influence the bone micromilieu. We point out how they interact with mediators of distinct signaling pathways such as the RANKL/OPG axis, BMP and WNT signaling, and affect the activity of bone remodeling cells within the endosteal niche summarizing their potential for therapeutic intervention.
- Published
- 2021
46. Hydrogen production in a semi‐single‐chamber microbial electrolysis cell based on anode encapsulated in a dialysis bag
- Author
-
Lea Ouaknin Hirsch, Alex Schechter, Bharath Gandu, Rivka Cahan, Irina Dubrovin, and Shmuel Rozenfeld
- Subjects
biology ,Renewable Energy, Sustainability and the Environment ,Chemistry ,Energy Engineering and Power Technology ,biology.organism_classification ,Dialysis tubing ,Anode ,Fuel Technology ,Nuclear Energy and Engineering ,Chemical engineering ,Microbial electrolysis cell ,Geobacter sulfurreducens ,Hydrogen production ,Single chamber - Published
- 2021
47. Probiotic bacteria stabilized in orally dissolving nanofibers prepared by high-speed electrospinning
- Author
-
Zsombor Kristóf Nagy, Monika Molnar, Júlia Domján, Ágnes Suhajda, Tamás Vigh, Sune K. Andersen, György Marosi, Eszter Pantea, Geert Verreck, Panna Vass, and Edit Hirsch
- Subjects
0106 biological sciences ,food.ingredient ,General Chemical Engineering ,Excipient ,01 natural sciences ,Biochemistry ,Dosage form ,chemistry.chemical_compound ,0404 agricultural biotechnology ,food ,010608 biotechnology ,Skimmed milk ,medicine ,Food science ,Lactose ,Chemistry ,food and beverages ,04 agricultural and veterinary sciences ,040401 food science ,Trehalose ,Electrospinning ,Nanofiber ,Mannitol ,Food Science ,Biotechnology ,medicine.drug - Abstract
To utilize the effect of probiotics in the oral cavity, an easily applicable, orally dissolving dosage form of Lactobacillus paracasei was prepared by high-speed electrospinning. The scaled-up electrostatic drying technology resulted in high productivity of submicronic, fast-dissolving fibers. To minimize the viability loss of the bacteria, polyvinyl alcohol-polyethylene oxide (PVA-PEO) based polymer systems combined with different stabilizing excipients (glucose, lactose, mannitol, saccharose, trehalose, inulin, and skim milk) were developed. The use of excipients was successful to decrease osmotic and dehydration stress while increasing bacterial survival during electrospinning and long-term storage. The application of trehalose, saccharose, and skim milk as stabilizing excipient, gave 80% or higher bacterial survival during electrospinning; furthermore, in skim milk and mannitol containing formulations 0.5 log unit and 0.2 log unit viability loss was detected after one year. Skim milk showed the best results considering survival rate and long-term stability: after 1 year of storage, a cell count of 7.4 109 CFU/g was measured at 7 °C and 1.56 1010 CFU/g at −20 °C (initial loading was 2.7 1010 CFU/g). Thus, electrospinning using well-selected excipients provides an adequate system that can sustain high-viability of probiotic cells during long-term storage.
- Published
- 2021
48. Gamma-spectrometric measurement procedure for a clearance concept of radioactively contaminated mercury from nuclear facilities
- Author
-
Larissa Klaß, Giuseppe Modolo, Marius Hirsch, Andreas Havenith, Andreas Wilden, Philipp Ritz, and John Kettler
- Subjects
Waste management ,Health, Toxicology and Mutagenesis ,Public Health, Environmental and Occupational Health ,chemistry.chemical_element ,02 engineering and technology ,Human decontamination ,Contamination ,Reuse ,021001 nanoscience & nanotechnology ,Pollution ,Analytical Chemistry ,Mercury (element) ,Nuclear facilities ,020401 chemical engineering ,Nuclear Energy and Engineering ,chemistry ,Hazardous waste ,ddc:540 ,Environmental science ,Radiology, Nuclear Medicine and imaging ,0204 chemical engineering ,0210 nano-technology ,National laboratory ,Spectroscopy - Abstract
Radioactive mercury waste constitutes a significant challenge, as no approved disposal concept yet exists for such waste in Germany. This work describes a decontamination and measurement procedure for a possible clearance of mercury from nuclear facilities and release into reuse or conventional hazardous waste disposal to reduce the amount of mercury in a nuclear repository. The measurement setup and procedure were developed and evaluated including Monte-Carlo N-Particle® Transport Code (MCNP® and Monte Carlo N-Particle® are registered trademarks owned by Los Alamos National Security, LLC, manager and operator of Los Alamos National Laboratory, (Werner 2018, Werner 2017)), simulations to ensure conservative assumptions during the measurements. Results from decontaminated mercury samples show that a clearance pursuant to the German regulations would be feasible.
- Published
- 2021
49. Ignition temperature of combustible liquids in mixtures of air with nitrous oxide
- Author
-
Elisabeth Brandes, Maria Mitu, Sabine Zakel, and Werner Hirsch
- Subjects
chemistry.chemical_compound ,Materials science ,Polymers and Plastics ,Chemical engineering ,chemistry ,Metals and Alloys ,Ceramics and Composites ,Autoignition temperature ,General Chemistry ,Nitrous oxide ,Electronic, Optical and Magnetic Materials - Published
- 2021
50. Conversion of calcium‐l‐methylfolate and (6S)‐5‐methyltetrahydrofolic acid glucosamine salt into dietary folate equivalents
- Author
-
Turck, Dominique, Bohn, Torsten, Castenmiller, Jacqueline, De Henauw, Stefaan, Hirsch-Ernst, Karen Ildico, Knutsen, Helle Katrine, Maciuk, Alexandre, Mangelsdorf, Inge, McArdle, Harry J., Naska, Androniki, Pelaez, Carmen, Siani, Alfonso, Thies, Frank, Tsabouri, Sophia, Vinceti, Marco, Cubadda, Francesco, Abrahantes, Jose Cortinas, Dumas, Celine, Ercolano, Valeria, Titz, Ariane, Pentieva, Kristina, and Nutr Novel Foods Food A, EFSA Panel
- Subjects
Agriculture and Food Sciences ,BIOAVAILABILITY ,Veterinary (miscellaneous) ,FOOD FOLATE ,INTESTINAL-ABSORPTION ,PROTEIN ,5‐MTHF glucosamine ,CaLMF ,DFE ,bioavailability ,food for specific groups ,food supplements ,fortified food ,FOLIC-ACID ,Plant Science ,Microbiology ,SUPPLEMENTATION ,supplements ,BINDING ,RELATIVE ,PLASMA ,food ,IN-VITRO DIGESTION ,5-MTHF glucosamine ,Chemistry ,MEMBRANE-TRANSPORT ,HOMOCYSTEINE CONCENTRATIONS ,Animal Science and Zoology ,Parasitology ,Food Science - Abstract
Following a request from the European Commission, the EFSA Panel on Nutrition, Novel Foods and Food Allergens (NDA) was asked to deliver a scientific opinion on the conversion of calcium-l-methylfolate and (6S)-5-methyltetrahydrofolic acid glucosamine salt (collectively called 5-MTHF hereafter) into dietary folate equivalents (DFE). Following a systematic review, the conclusions of the opinion are based on one intervention study in adults for intakes < 400 mu g/day and three intervention studies in adults for intakes >= 400 mu g/day. At intakes below 400 mu g/day, folic acid (FA) is assumed to be linearly related to responses of biomarkers of intake and status and is an appropriate comparator for deriving a DFE conversion factor for 5-MTHF. It is proposed to use the same factor as for folic acid for conversion of 5-MTHF into DFE for intakes < 400 mu g/day. As such intake levels are unlikely to be exceeded through fortified food consumption, the conversion factor of 1.7 relative to natural food folate (NF) could be applied to 5-MTHF added to foods and to food supplements providing < 400 mu g/day. At 400 mu g/day, 5-MTHF was found to be more bioavailable than folic acid and a conversion factor of 2 is proposed for this intake level and for higher intakes. The derived DFE equations are DFE = NF + 1.7 x FA + 1.7 x 5-MTHF for fortified foods and food supplements providing intakes < 400 mu g/day; and DFE = NF + 1.7 x FA + 2.0 x 5-MTHF for food supplements providing intakes >= 400 mu g/day. Although this assessment applies to calcium-L-methylfolate and 5-MTHF glucosamine salt, it is considered that the influence of the cation on bioavailability is likely to be within the margin of error of the proposed DFE equations. Therefore, the proposed equations can also be applied to 5-MTHF associated with other cations.
- Published
- 2022
Catalog
Discovery Service for Jio Institute Digital Library
For full access to our library's resources, please sign in.