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71.
The antagonism of glucocorticoid inhibition of wound healing in rats by growth hormone-releasing factor 总被引:1,自引:0,他引:1
S F Kelley A M Felix H P Ehrlich 《Proceedings of the Society for Experimental Biology and Medicine. Society for Experimental Biology and Medicine (New York, N.Y.)》1990,194(4):320-326
Daily therapeutic injections of cortisone to rats will cause weight loss and impaired wound healing. Weight loss is attributed to the catabolic effect of steroid, whereas impaired healing is associated with reductions in fibroplasia and connective tissue deposition. As the major structural protein component of connective tissue is collagen, its absence is responsible for the retarded gain in wound breaking strength. Cortisone also blocks wound closure by inhibiting wound contraction. An anabolic agent such as growth hormone may antagonize the effect of cortisone on the wound healing process. Endogenous GH can be released from the pituitary by exogenous injections of growth hormone-releasing factor (GRF). Two synthetic GRF peptides, a natural 44-amino acid peptide of the human GRF sequence, GRF-44, and an N-terminally substituted analog 29 residues, GRF-29A, were studied. Each was given twice daily with a single daily injection of cortisone for a 7-day period. Concurrent administration of GRF-44 or GRF-29A and cortisone to rats had no effect on restored body weight loss or inhibited wound contraction. While GRF-44 restored collagen deposition and caused restored wound breaking strength, GRF-29A was ineffective in restoring either. GRF-44, a synthetic peptide that stimulates pituitary release of growth hormone, antagonized some of the inhibiting effect of steroid on wound repair by promoting fibroplasia and collagen deposition. 相似文献
72.
Galanter JM Fernandez-Lopez JC Gignoux CR Barnholtz-Sloan J Fernandez-Rozadilla C Via M Hidalgo-Miranda A Contreras AV Figueroa LU Raska P Jimenez-Sanchez G Zolezzi IS Torres M Ponte CR Ruiz Y Salas A Nguyen E Eng C Borjas L Zabala W Barreto G González FR Ibarra A Taboada P Porras L Moreno F Bigham A Gutierrez G Brutsaert T León-Velarde F Moore LG Vargas E Cruz M Escobedo J Rodriguez-Santana J Rodriguez-Cintrón W Chapela R Ford JG Bustamante C Seminara D Shriver M Ziv E Burchard EG Haile R 《PLoS genetics》2012,8(3):e1002554
Most individuals throughout the Americas are admixed descendants of Native American, European, and African ancestors. Complex historical factors have resulted in varying proportions of ancestral contributions between individuals within and among ethnic groups. We developed a panel of 446 ancestry informative markers (AIMs) optimized to estimate ancestral proportions in individuals and populations throughout Latin America. We used genome-wide data from 953 individuals from diverse African, European, and Native American populations to select AIMs optimized for each of the three main continental populations that form the basis of modern Latin American populations. We selected markers on the basis of locus-specific branch length to be informative, well distributed throughout the genome, capable of being genotyped on widely available commercial platforms, and applicable throughout the Americas by minimizing within-continent heterogeneity. We then validated the panel in samples from four admixed populations by comparing ancestry estimates based on the AIMs panel to estimates based on genome-wide association study (GWAS) data. The panel provided balanced discriminatory power among the three ancestral populations and accurate estimates of individual ancestry proportions (R2 > 0.9 for ancestral components with significant between-subject variance). Finally, we genotyped samples from 18 populations from Latin America using the AIMs panel and estimated variability in ancestry within and between these populations. This panel and its reference genotype information will be useful resources to explore population history of admixture in Latin America and to correct for the potential effects of population stratification in admixed samples in the region. 相似文献
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74.
Sulieman Ibraheem Shelash Al-Hawary Saade Abdalkareem Jasim Ahmed Hjazi Enwa Felix Oghenemaro Irwanjot Kaur Abhinav Kumar Ahmed Muzahem Al-Ani Enas R. Alwaily Ahmed Huseen Redhee Yasser Fakri Mustafa 《Cell biochemistry and function》2024,42(2):e3978
Ovarian cancer continues to be a difficult medical issue that affects millions of individuals worldwide. Important platforms for cancer immunotherapy include checkpoint inhibitors, chimeric antigen receptor T cells, bispecific antibodies, cancer vaccines, and other cell-based treatments. To avoid numerous infectious illnesses, conventional vaccinations based on synthetic peptides, recombinant subunit vaccines, and live attenuated and inactivated pathogens are frequently utilized. Vaccine manufacturing processes, however, are not entirely safe and carry a significant danger of contaminating living microorganisms. As a result, the creation of substitute vaccinations is required for both viral and noninfectious illnesses, including cancer. Recently, there has been testing of nucleic acid vaccines, or NAVs, as a cancer therapeutic. Tumor antigens (TAs) are genetically encoded by DNA and mRNA vaccines, which the host uses to trigger immune responses against ovarian cancer cells that exhibit the TAs. Despite being straightforward, safe, and easy to produce, NAVs are not currently thought to be an ideal replacement for peptide vaccines. Some obstacles to this strategy include selecting the appropriate therapeutic agents (TAs), inadequate immunogenicity, and the immunosuppressive characteristic of ovarian cancer. We focus on strategies that have been employed to increase NAVs' effectiveness in the fight against ovarian cancer in this review. 相似文献
75.
Matthias Weiling Christian Lechtenfeld Felix Pfeiffer Lars Frankenstein Diddo Diddens Jian-Fen Wang Sascha Nowak Masoud Baghernejad 《Liver Transplantation》2024,14(5):2303568
The implementation of silicon (Si)-containing negative electrodes is widely discussed as an approach to increase the specific capacity of lithium-ion batteries. However, challenges caused by severe volume changes and continuous (re-)formation of the solid-electrolyte interphase (SEI) on Si need to be overcome. The volume changes lead to electrolyte consumption and active lithium loss, decaying the cell performance and cycle life. Herein, the additive 2-sulfobenzoic acid anhydride (2-SBA) is utilized as an SEI-forming electrolyte additive for SiOx-containing anodes. The addition of 2-SBA to a state-of-the-art carbonate-based electrolyte in high-voltage LiNi0.8Mn0.1Co0.1O2, NMC811||artificial graphite +20% SiOx pouch cells leads to improved electrochemical performance, resulting in a doubled cell cycle life. The origin of the enhanced cell performance is mechanistically investigated by developing an advanced experimental technique based on operando attenuated total reflection Fourier-transform infrared (ATR-FTIR) spectroscopy. The operando ATR-FTIR spectroscopy results elucidate the degradation mechanism via anhydride ring-opening reactions after electrochemical reduction on the anode surface. Additionally, ion chromatography conductivity detection mass spectrometry, scanning electron microscopy, energy dispersive X-ray analysis, and quantum chemistry calculations are employed to further elucidate the working mechanisms of the additive and its degradation products. 相似文献
76.
Jin-Woo Lee Cheng Sun Jinho Lee Dong Jun Kim Won Jung Kang Seungbok Lee Donguk Kim Jinseok Park Tan Ngoc-Lan Phan Zhengping Tan Felix Sunjoo Kim Jung-Yong Lee Xichang Bao Taek-Soo Kim Yun-Hi Kim Bumjoon J. Kim 《Liver Transplantation》2024,14(8):2303872
High power conversion efficiency (PCE), long-term stability, and mechanical robustness are prerequisites for the commercial applications of organic solar cells (OSCs). In this study, a new star-shaped trimer acceptor (TYT-S) is developed and high-performance OSCs with a PCE of 19.0%, high photo-stability (t80% lifetime = 2600 h under 1-sun illumination), and mechanical robustness with a crack-onset strain (COS) of 21.6% are achieved. The isotropic molecular structure of TYT-S affords efficient multi-directional charge transport and high electron mobility. Furthermore, its amorphous structure prevents the formation of brittle crystal-to-crystal interfaces, significantly enhancing the mechanical properties of the OSC. As a result, the TYT-S-based OSCs demonstrate a significantly higher PCE (19.0%) and stretchability (COS = 21.6%) than the linear-shaped trimer acceptor (TYT-L)-based OSCs (PCE = 17.5% and COS = 6.4%) and the small-molecule acceptor (MYT)-based OSCs (PCE = 16.5% and COS = 1.3%). In addition, the increased molecular size of TYT-S, relative to that of MYT and dimer (DYT), suppresses the diffusion kinetics of the acceptor molecules, substantially improving the photostability of the OSCs. Finally, to effectively demonstrate the potential of TYT-S, intrinsically stretchable (IS)-OSCs are constructed. The TYT-S-based IS-OSCs exhibit high device stretchability (strain at PCE80% = 31%) and PCE of 14.4%. 相似文献
77.
Felix Molter Armin W. Thomas Scott A. Huettel Hauke R. Heekeren Peter N. C. Mohr 《PLoS computational biology》2022,18(7)
Choices are influenced by gaze allocation during deliberation, so that fixating an alternative longer leads to increased probability of choosing it. Gaze-dependent evidence accumulation provides a parsimonious account of choices, response times and gaze-behaviour in many simple decision scenarios. Here, we test whether this framework can also predict more complex context-dependent patterns of choice in a three-alternative risky choice task, where choices and eye movements were subject to attraction and compromise effects. Choices were best described by a gaze-dependent evidence accumulation model, where subjective values of alternatives are discounted while not fixated. Finally, we performed a systematic search over a large model space, allowing us to evaluate the relative contribution of different forms of gaze-dependence and additional mechanisms previously not considered by gaze-dependent accumulation models. Gaze-dependence remained the most important mechanism, but participants with strong attraction effects employed an additional similarity-dependent inhibition mechanism found in other models of multi-alternative multi-attribute choice. 相似文献
78.
Clara R. Burgert-Brucker Molly W. Adams Pia Mingkwan Rebecca Flueckiger Jeremiah M. Ngondi Anthony W. Solomon Emma M. Harding-Esch 《PLoS neglected tropical diseases》2022,16(4)
BackgroundTrachoma is targeted for global elimination as a public health problem by 2030. Understanding individual, household, or community-associated factors that may lead to continued transmission or risk of recrudescence in areas where elimination has previously been achieved, is essential in reaching and maintaining trachoma elimination. We aimed to identify climatic, demographic, environmental, infrastructural, and socioeconomic factors associated in the literature with trachoma at community-level and assess the strength of their association with trachoma. Because of the potential power of geospatial analysis to delineate the variables most strongly associated with differences in trachoma prevalence, we then looked in detail at geospatial analysis methods used in previous trachoma studies.MethodsWe conducted a systematic literature review using five databases: Medline, Embase, Global Health, Dissertations & Theses Global, and Web of Science, including publications from January 1950 to January 2021. The review protocol was prospectively registered with PROSPERO (CRD42020191718).ResultsOf 35 eligible studies, 29 included 59 different trachoma-associated factors, with eight studies also including spatial analysis methods. Six studies included spatial analysis methods only. Higher trachomatous inflammation—follicular (TF) prevalence was associated with areas that: had lower mean annual precipitation, lower mean annual temperatures, and lower altitudes; were rural, were less accessible, had fewer medical services, had fewer schools; and had lower access to water and sanitation. Higher trachomatous trichiasis (TT) prevalence was associated with higher aridity index and increased distance to stable nightlights. Of the 14 studies that included spatial methods, 11 used exploratory spatial data analysis methods, three used interpolation methods, and seven used spatial modelling methods.ConclusionResearchers and decision-makers should consider the inclusion and potential influence of trachoma-associated factors as part of both research activities and programmatic priorities. The use of geospatial methods in trachoma studies remains limited but offers the potential to define disease hotspots and areas of potential recrudescence to inform local, national, and global programmatic needs. 相似文献
79.
Ohne ZusammenfassungHerrn Univ.-Prof. Dr. AdolfSperlich zum 80. Geburtstag gewidmet. 相似文献
80.