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991.
Yi Zhang Min Chen Yuanyuan Zhou Wenhao Li Yonghui Lee Hiroyuki Kanda Xiao‐Xin Gao Ruiyuan Hu Keith Gregory Brooks Rashid Zia Sachin Kinge Nitin P. Padture Mohammad Khaja Nazeeruddin 《Liver Transplantation》2020,10(29)
Composition and film quality of perovskite are crucial for the further improvement of perovskite solar cells (PSCs), including efficiency, reproducibility, and stability. Here, it is demonstrated that by simply mixing 50% of formamidinium (FA+) into methylammonium lead iodide (MAPbI3), a highly crystalline, stable phase, and compact, polycrystalline grain morphology perovskite is formed by using a solvent‐mediated phase transformation process via the synergism of dimethyl sulfoxide and diethyl ether, which shows long carrier lifetime, low trap state density, and a record certified 21.8% power conversion efficiency (PCE) in pure‐iodide, alkaline‐metal‐free MA0.5FA0.5PbI3 perovskite‐based PSCs. These PSCs show very high operational stability, with 85% PCE retention upon 1000 h 1 Sun intensity illumination. A 17.33% PCE module (6.5 × 7 cm2) is also demonstrated, attesting to the scalability of such devices. 相似文献
992.
Savannah Stuart‐Dahl Edith Martinez‐Guerra Bahareh Kokabian Veera Gnaneswar Gude Renotta Smith John Brooks 《Engineering in Life Science》2020,20(3-4):54-66
In this research, low strength synthetic wastewaters with chemical oxygen demand less than 300 mg L?1 were treated at different concentrations in a bioelectrochemical desalination process. A process optimization model was utilized to study the performance of the photosynthetic bioelectrochemical desalination process. The variables include substrate (chemical oxygen demand) concentration, total dissolved solids, and microalgae biomass concentration in the cathode chamber. Relationships between the chemical oxygen demand concentration, microalgae, and salt concentrations were evaluated. Power densities and potential energy benefits from microalgal biomass growth were discussed. The results from this study demonstrated the reliability and reproducibility of the photosynthetic microbial desalination process performance followed by a response surface methodology optimization. This study also confirms the suitability of bioelectrochemical desalination process for treating low substrate wastewaters such as agricultural wastewaters, anaerobic digester effluents, and septic tank effluents for net energy production and water desalination. 相似文献
993.
Background and Objectives
Obesity is emerging as the most significant health concern of the twenty-first century. A wealth of neuroimaging data suggest that weight gain might be related to aberrant brain function, particularly in prefrontal cortical regions modulating mesolimbic addictive responses to food. Nevertheless, food addiction is currently a model hotly debated. Here, we conduct a meta-analysis of neuroimaging data, examining the most common functional differences between normal-weight and obese participants in response to food stimuli.Data Source
We conducted a search using several journal databases and adhered to the ‘Preferred Reporting Items for Systematic Reviews and Meta-analyses’ (PRISMA) method. To this aim, 10 studies were found with a total of 126 obese participants, 129 healthy controls, equaling 184 foci (146 increased, 38 decreased activation) using the Activation Likelihood Estimation (ALE) technique. Out of the 10 studies, 7 investigated neural responses to food versus non-food images.Results
In response to food images, obese in comparison to healthy weight subjects had increased activation in the left dorsomedial prefrontal cortex, right parahippocampal gyrus, right precentral gyrus and right anterior cingulate cortex, and reduced activation in the left dorsolateral prefrontal cortex and left insular cortex.Conclusions
Prefrontal cortex areas linked to cognitive evaluation processes, such as evaluation of rewarding stimuli, as well as explicit memory regions, appear most consistently activated in response to images of food in those who are obese. Conversely, a reduced activation in brain regions associated with cognitive control and interoceptive awareness of sensations in the body might indicate a weakened control system, combined with hypo-sensitivity to satiety and discomfort signals after eating in those who are prone to overeat. 相似文献994.
Richelle C. Charles Tania Sultana Mohammad Murshid Alam Yanan Yu Ying Wu-Freeman Meagan Kelly Bufano Sean M. Rollins Lillian Tsai Jason B. Harris Regina C. LaRocque Daniel T. Leung W. Abdullah Brooks Tran Vu Thieu Nga Sabina Dongol Buddha Basnyat Stephen B. Calderwood Jeremy Farrar Farhana Khanam John S. Gunn Firdausi Qadri Stephen Baker Edward T. Ryan 《PLoS neglected tropical diseases》2013,7(8)
Background
Salmonella enterica serotype Typhi can colonize and persist in the biliary tract of infected individuals, resulting in a state of asymptomatic chronic carriage. Chronic carriers may act as persistent reservoirs of infection within a community and may introduce infection to susceptible individuals and new communities. Little is known about the interaction between the host and pathogen in the biliary tract of chronic carriers, and there is currently no reliable diagnostic assay to identify asymptomatic S. Typhi carriage.Methodology/Principal Findings
To study host-pathogen interactions in the biliary tract during S. Typhi carriage, we applied an immunoscreening technique called in vivo-induced antigen technology (IVIAT), to identify potential biomarkers unique to carriers. IVIAT identifies humorally immunogenic bacterial antigens expressed uniquely in the in vivo environment, and we hypothesized that S. Typhi surviving in the biliary tract of humans may express a distinct antigenic profile. Thirteen S. Typhi antigens that were immunoreactive in carriers, but not in healthy individuals from a typhoid endemic area, were identified. The identified antigens included a number of putative membrane proteins, lipoproteins, and hemolysin-related proteins. YncE (STY1479), an uncharacterized protein with an ATP-binding motif, gave prominent responses in our screen. The response to YncE in patients whose biliary tract contained S. Typhi was compared to responses in patients whose biliary tract did not contain S. Typhi, patients with acute typhoid fever, and healthy controls residing in a typhoid endemic area. Seven of 10 (70%) chronic carriers, 0 of 8 bile culture-negative controls (0%), 0 of 8 healthy Bangladeshis (0%), and 1 of 8 (12.5%) Bangladeshis with acute typhoid fever had detectable anti-YncE IgG in blood. IgA responses were also present.Conclusions/Significance
Further evaluation of YncE and other antigens identified by IVIAT could lead to the development of improved diagnostic assays to identify asymptomatic S. Typhi carriers. 相似文献995.
Rafi Chapanian Iren Constantinescu Donald E. Brooks Mark D. Scott Jayachandran Kizhakkedathu 《Journal of visualized experiments : JoVE》2013,(71)
Red blood cell (RBC) transfusion is vital for the treatment of a number of acute and chronic medical problems such as thalassemia major and sickle cell anemia 1-3. Due to the presence of multitude of antigens on the RBC surface (~308 known antigens 4), patients in the chronic blood transfusion therapy develop alloantibodies due to the miss match of minor antigens on transfused RBCs 4, 5. Grafting of hydrophilic polymers such as polyethylene glycol (PEG) and hyperbranched polyglycerol (HPG) forms an exclusion layer on RBC membrane that prevents the interaction of antibodies with surface antigens without affecting the passage of small molecules such as oxygen ,glucose, and ions3. At present no method is available for the generation of universal red blood donor cells in part because of the daunting challenge presented by the presence of large number of antigens (protein and carbohydrate based) on the RBC surface and the development of such methods will significantly improve transfusion safety, and dramatically improve the availability and use of RBCs. In this report, the experiments that are used to develop antigen protected functional RBCs by the membrane grafting of HPG and their characterization are presented. HPGs are highly biocompatible compact polymers 6, 7, and are expected to be located within the cell glycocalyx that surrounds the lipid membrane 8, 9 and mask RBC surface antigens10, 11. 相似文献
996.
997.
Kallol Ray Chaudhuri Jose Manuel Rojo Anthony H. V. Schapira David J. Brooks Fabrizio Stocchi Per Odin Angelo Antonini Richard J. Brown Pablo Martinez-Martin 《PloS one》2013,8(2)
Background
Non-motor symptoms are present in Parkinson''s disease (PD) and a key determinant of quality of life. The Non-motor Symptoms Scale (NMSS) is a validated scale that allows quantifying frequency and severity (burden) of NMS. We report a proposal for using NMSS scores to determine levels of NMS burden (NMSB) and to complete PD patient classification.Methods
This was an observational, cross-sectional international study of 935 consecutive patients. Using a distribution of NMSS scores by quartiles, a classification based on levels from 0 (no NMSB at all) to 4 (very severe NMSB) was obtained and its relation with Hoehn and Yahr (HY) staging, motor and health-related quality of life scales was analyzed. Concordance between NMSB levels and grouping based on clinician''s global impression of severity, using categorical regression, was determined. Disability and HRQoL predictors were identified by multiple regression models.Results
The distribution of motor and QoL scales scores by HY and NMSB levels was significantly discriminative. The difference in the classification of cases for both methods, HY and NMSB, was significant (gamma = 0.45; ASE = 0.032). Concordance between NMSB and global severity-based levels from categorical regression was 91.8%, (kappaw = 0.97). NMS score was predictor of disability and QoL.Conclusions
Current clinical practice does not address a need for inclusion of non-motor scores in routine assessment of PD in spite of the overwhelming influence of NMS on disability and quality of life. Our data overcome the problems of “pure motor assessment” and we propose a combined approach with addition of NMSB levels to standard motor assessments. 相似文献998.
Flavia C. Massaro Peter R. Brooks Helen M. Wallace Vianne Nsengiyumva Lorraine Narokai Fraser D. Russell 《PloS one》2013,8(11)
Bee propolis is a mixture of plant resins and bee secretions. While bioactivity of honeybee propolis has been reported previously, information is limited on propolis from Australian stingless bees (Tetragonula carbonaria). The aim of this study was to investigate possible vasomodulatory effects of propolis in KCl-precontracted porcine coronary arteries using an ex vivo tissue bath assay. Polar extracts of propolis produced a dose-dependent relaxant response (EC50=44.7±7.0 μg/ml), which was unaffected by endothelial denudation, suggesting a direct effect on smooth muscle. Propolis markedly attenuated a contractile response to Ca2+ in vessels that were depolarised with 60 mM KCl, in Ca2+-free Krebs solution. Propolis (160 µg/ml) reduced vascular tone in KCl pre-contracted vessels to near-baseline levels over 90 min, and this effect was partially reversible with 6h washout. Some loss in membrane integrity, but no loss in mitochondrial function was detected after 90 min exposure of human cultured umbilical vein endothelial cells to 160 µg/ml propolis. We conclude that Australian stingless bee (T. carbonaria) propolis relaxes porcine coronary artery in an endothelial-independent manner that involves inhibition of voltage-gated Ca2+ channels. This effect is partially and slowly reversible upon washout. Further studies are required to determine the therapeutic potential of Australian stingless bee propolis for conditions in which vascular supply is compromised. 相似文献
999.
Kristin A. Connors Bowen Du Patrick N. Fitzsimmons C. Kevin Chambliss John W. Nichols Bryan W. Brooks 《Chirality》2013,25(11):763-767
The occurrence of pharmaceuticals in the environment represents a challenge of emerging concern. Many pharmaceuticals are chiral compounds; however, few studies have examined the relative toxicity of pharmaceutical enantiomers to wildlife. Further, our understanding of stereospecific pharmacokinetics remains largely informed by research on humans and a few well‐studied laboratory test animals, and not by studies conducted with environmentally relevant species, including fish. The objective of this study was to investigate whether rainbow trout display stereospecific in vitro metabolism of three common chiral pharmaceuticals. Metabolism by trout liver S9 fractions was evaluated using a substrate depletion approach, which provides an estimate of intrinsic hepatic clearance (CLIN VITRO,INT). No biotransformation was observed for rac‐, R‐, or S‐fluoxetine. Ibuprofen, including both enantiomers and the racemic mixture, appeared to undergo slow metabolism, but the resulting substrate depletion curves did not differ significantly from those of inactive controls. Contrary to relative clearance rates in humans, S(?)‐propranolol was more rapidly cleared than the R(+)‐ enantiomer. This work demonstrates that relative clearance rates and the effects of racemic mixtures in trout could not have been predicted based on human data. Additional research describing species differences and exploring tools for species extrapolation in biomedical and environmental studies is needed. Chirality 25:763–767, 2013, © 2013 Wiley Periodicals, Inc. 相似文献
1000.
Xiaozhen Yu Xiongwu Wu Guillermo A. Bermejo Bernard R. Brooks Justin W. Taraska 《Structure (London, England : 1993)》2013,21(1):9-19
Highlights? A high-throughput tmFRET method is developed ? tmFRET is used to map distances in MBP in the HOLO and APO states ? tmFRET accurately determines the structure and movements of MBP to within a few angstroms ? tmFRET-derived distances are used as constraints in molecular simulations 相似文献