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991.
Sewar Alkhashrom Jintawee Kicuntod Sigrun Hge Johannes Schweininger Yves A. Muller Peter Lischka Manfred Marschall Jutta Eichler 《Viruses》2021,13(3)
Nuclear egress is an essential process in the replication of human cytomegalovirus (HCMV), as it enables the migration of newly formed viral capsids from the nucleus into the cytoplasm. Inhibition of the HCMV core nuclear egress complex (core NEC), composed of viral proteins pUL50 and pUL53, has been proposed as a potential new target for the treatment of HCMV infection and disease. Here, we present a new type of small molecule inhibitors of HCMV core NEC formation, which inhibit the pUL50-pUL53 interaction at nanomolar concentrations. These inhibitors, i.e., verteporfin and merbromin, were identified through the screening of the Prestwick Chemical Library® of approved drug compounds. The inhibitory effect of merbromin is both compound- and target-specific, as no inhibition was seen for other mercury-organic compounds. Furthermore, merbromin does not inhibit an unrelated protein–protein interaction either. More importantly, merbromin was found to inhibit HCMV infection of cells in three different assays, as well as to disrupt HCMV NEC nuclear rim formation. Thus, while not being an ideal drug candidate by itself, merbromin may serve as a blueprint for small molecules with high HCMV core NEC inhibitory potential, as candidates for novel anti-herpesviral drugs. 相似文献
992.
Human metapneumovirus (HMPV) is an important cause of upper and lower respiratory tract disease in individuals of all ages. It is estimated that most individuals will be infected by HMPV by the age of five years old. Despite this burden of disease, there remain caveats in our knowledge of global genetic diversity due to a lack of HMPV sequencing, particularly at the whole-genome scale. The purpose of this study was to create a simple and robust approach for HMPV whole-genome sequencing to be used for genomic epidemiological studies. To design our assay, all available HMPV full-length genome sequences were downloaded from the National Center for Biotechnology Information (NCBI) GenBank database and used to design four primer sets to amplify long, overlapping amplicons spanning the viral genome and, importantly, specific to all known HMPV subtypes. These amplicons were then pooled and sequenced on an Illumina iSeq 100 (Illumina, San Diego, CA, USA); however, the approach is suitable to other common sequencing platforms. We demonstrate the utility of this method using a representative subset of clinical samples and examine these sequences using a phylogenetic approach. Here we present an amplicon-based method for the whole-genome sequencing of HMPV from clinical extracts that can be used to better inform genomic studies of HMPV epidemiology and evolution. 相似文献
993.
Identification of Nucleoside Analogs as Inducers of Neuronal Differentiation in a Human Reporter Cell Line and Adult Stem Cells 下载免费PDF全文
Katharina Raasch Edith Malecki Maria Siemann Malayko M. Martinez Jürgen J. Heinisch Janine Müller Lidia Bakota Christian Kaltschmidt Barbara Kaltschmidt Helmut Rosemeyer Roland Brandt 《Chemical biology & drug design》2015,86(2):129-143
Nucleoside analogs (NSAs) were among the first chemotherapeutic agents and could also be useful for the manipulation of cell fate. To investigate the potential of NSAs for the induction of neuronal differentiation, we developed a novel phenotypic assay based on a human neuron‐committed teratocarcinoma cell line (NT2) as a model for neuronal progenitors and constructed a NT2‐based reporter cell line that expressed eGFP under the control of a neuron‐specific promoter. We tested 38 structurally related NSAs and determined their activity to induce neuronal differentiation by immunocytochemistry of neuronal marker proteins, live cell imaging, fluorometric detection and immunoblot analysis. We identified twelve NSAs, which induced neuronal differentiation to different extents. NSAs with highest activity carried a halogen substituent at their pyrimidine nucleobase and an unmodified or 2′‐O‐methyl substituted 2‐deoxy‐β‐D‐ribofuranosyl residue as glyconic moiety. Cladribine, a purine nucleoside with similar structural features and in use to treat leukemia and multiple sclerosis, induced also differentiation of adult human neural crest‐derived stem cells. Our results suggest that NSAs could be useful for the manipulation of neuronal cell fate in cell replacement therapy or treatment of neurodegenerative disorders. The data on the structure and function relationship will help to design compounds with increased activity and low toxicity. 相似文献
994.
Hideaki Kato Sei Samukawa Hiroyuki Takahashi Hideaki Nakajima 《Journal of infection and chemotherapy》2019,25(11):920-924
The clinical characteristics of Pneumocystis jirovecii pneumonia (PCP) in patients with immunodeficiency virus (HIV) infection (HIV-PCP) differ from those in patients without HIV infection (non-HIV-PCP). We analyzed 31 adult HIV-PCP cases and 44 non-HIV-PCP cases between 2008 and 2018. The symptomatic period before the diagnosis was shorter in non-HIV-PCP (5 [3–8] days vs. 29 [14–55] days, P < 0.001) and the overall survival rate was lower in the non-HIV-PCP group (P = 0.022). Serum β-D glucan positivity (72.7% vs. 93.5%, P = 0.034) and Grocott stain positivity for Pneumocystis jirovecii in the bronchoalveolar lavage fluid (4.3% vs. 73.3%, P < 0.001) were significantly lower in the non-HIV-PCP group. This difficulty in laboratory diagnosis possibly resulted in the administration of concurrent antibiotics such as quinolones and macrolides (56.8% vs. 19.4% P = 0.002) in the non-HIV-PCP group. The adverse effects due to trimethoprim-sulfamethoxazole were more frequently observed in HIV-PCP (86.2% vs. 35.3%, P < 0.001). The duration of discontinuation of trimethoprim-sulfamethoxazole was 11 [8–14.5] days in HIV-PCP cases. Co-administration of adjunctive corticosteroid therapy did not mitigate hypersensitivity to trimethoprim-sulfamethoxazole. Our analysis indicated that the characteristics of PCP in patients with or without HIV was quite different. HIV-positive patients with PCP should be monitored closely to avoid adverse effects due to trimethoprim-sulfamethoxazole. Because positivity polymerase chain reaction test for P. jirovecii remained high (91.7%), it is suggested that bronchofiberscopy is warranted for diagnosis of PCP in HIV-negative patients. 相似文献
995.
H+/amino acid transporter 1 (PAT1) is the imino acid carrier: An intestinal nutrient/drug transporter in human and rat 总被引:1,自引:0,他引:1
996.
997.
The herpesvirus Human Cytomegalovirus (HCMV) is an important opportunistic infection in recipients of allogeneic haemopoietic stem cell transplants, in whom HCMV-specific CD8+ and CD4+ T-cell responses are impaired. The nature of the HCMV-specific T-cell response in healthy virus carriers has been characterised in detail. High frequencies of circulating CD8+ T-cells that recognise defined viral peptides are maintained for years, and include individual CD8+ clones that have undergone extensive clonal expansion and phenotypic diversification in vivo. Following stem cell transplantation, the kinetics of HCMV-specific CD8+ T-cell reconstitution in the recipient are related to the presence or absence of antigen-experienced CD8+ T-cells transferred via the allograft, and to the presence of the virus in the recipient. We discuss recent progress in our understanding of HCMV-specific immunity in healthy virus carriers and in recipients after alloSCT. 相似文献
998.
Wolfgang Lutz Erich Striessnig Anna Dimitrova Simone Ghislandi Anastasia Lijadi Claudia Reiter Sonja Spitzer Dilek Yildiz 《Proceedings of the National Academy of Sciences of the United States of America》2021,118(12)
Sustainable development (SD) as popularized by the Brundtland Commission and politically enshrined in the Sustainable Development Goals has been the explicit focus of sustainability science. While there is broad agreement that the trend of human well-being () over time should serve as a sustainability criterion, the literature so far has mostly addressed this in terms of its determinants rather than focusing on itself. There is broad agreement that an indicator for should have multiple constituents, clearly going beyond gross domestic product. Here, we propose a tailor-made indicator to serve precisely this purpose following a set of specified desiderata, including its applicability to flexibly defined subnational populations by gender, place of residence, ethnicity, and other relevant characteristics. The indicator, years of good life (YoGL), reflects the evident fact that in order to be able to enjoy any quality of life, one has to be alive and thus is primarily based on life expectancy. However, since mere survival is not considered good enough, life years are counted conditional on meeting minimum standards in two dimensions: the objective dimension of capable longevity (consisting of being out of absolute poverty and enjoying minimal levels of physical and cognitive health) and the subjective dimension of overall life satisfaction. We illustrate the calculation of this indicator for countries and subpopulations at different stages of development and with different degrees of data availability.Sustainability science refers to the most comprehensive scholarly effort to understand the interactions between natural and social systems in order to assess whether certain developmental pathways can be considered sustainable. This should also include the possible negative effects of environmental changes, such as climate change and biodiversity loss, on future human well-being. In this paper, we propose a tailor-made indicator to assess long-term human well-being as the ultimate end of sustainable development. This indicator, called “years of good life” (YoGL), is designed in such a way that it can be both empirically measured—which is the focus of this paper—and modeled in its long-term future trends—which will be the focus of future work.When assessing changes over time in the well-being of certain human populations (or subpopulations, as defined, e.g., by gender, ethnicity, urban/rural place of residence, or other social groupings), one can focus on the determinants or the constituents of well-being. In sustainability science, thus far, empirical and theoretical research has placed more emphasis on studying the determinants, including environmental services (1), whereas specifying its constituents has received less systematic attention, often leaving us with nothing but the unspecific notion of “utility.” The focus on determinants has led to the concept of “inclusive wealth” (IW) which can be used to assess whether a society is on a sustainable development trajectory in terms of the productive base necessary to maintain a high standard of living in the future (2). However, empirically measuring the values and relative effects of the different capitals determining human well-being remains extremely challenging and “no current attempt to date can be said to be fully inclusive” (3).The idea behind YoGL, on the other hand, is to study sustainability by focusing explicitly on the constituents of well-being and its change over time. In doing so, YoGL avoids several of the pitfalls by which the IW approach is plagued (3, 4). For example, rather than making contestable quantitative assessments of the relative contributions of the different determinants of well-being, the demographic approach underlying YoGL provides numerical values of human well-being directly, expressed as the average number of years of good life a person can expect to live as part of a given subpopulation under the conditions of a specified point in time. Based on the assumed universal nature of its unit of measurement—YoGL lived today in one specific population has the same meaning as YoGL lived in the future or in another population—the indicator has a time-independent meaning. This also avoids the pitfalls of specifying a rate at which to discount future well-being, which have become apparent at least since the debates around the Stern report (5). YoGL allows us to directly compare human well-being across different subpopulations and generations. Moreover, while all estimates of the different determinants of future human well-being are highly sensitive to population growth, as a measure referring to per-person well-being the derivation of YoGL is not directly affected by assumptions about the future trajectory of population size. Finally, as stressed by Dasgupta (6), the nature of determinants can change over time and across places depending on different commodities and technological regimes, whereas the constituents of well-being—as used in YoGL—are arguably shared across space and time.In the following, we will first present the proposed design of the indicator. We will then provide a step-by-step user’s guide for empirically deriving YoGL based on the most appropriate available data source, before offering examples of how it can be calculated based on auxiliary information on populations for which the necessary data are not yet fully available. We will close with a discussion and brief outlook as to what is still needed to use this indicator for the assessment of sustainability. 相似文献
999.
J Roth 《Metabolism: clinical and experimental》1973,22(8):1059-1073
1000.
中国结核病防治人力资源数量研究 总被引:6,自引:1,他引:6
目的探索结防专业机构人力资源研究的方法和技术,掌握我国结防资源状况,为政府部门制定政策提供参考。方法利用和分析3个全国性调查数据,即2006年进行的6省(直辖市)专题调查,2005年全国结防规划中期评估和2005年全国结防培训需求调查。结果2001—2005年全国结防机构专职结防人员从19 375人持续缓慢增加到24 056人,年平均增长率为5.6%;按照国家推荐的人员配备最低标准,全国省级、市级和县级结防机构专业人员数量不能达到要求的比例分别是64.5%、70.6%和40.1%;按照机构自身提出的要求,省级、市级和县级机构的现有人员满足需要程度分别为76%、67%和63%;近5年,全国结防系统的人员流出率先上升而后降低,而流入率不断增高,结防人员以竞争方式流入机构的占44.0%,非竞争流入占43.3%,主动流出机构的人员占45.5%,被动流出的占36.5%。结论应掌握我国结防人力资源数量变化规律,从长远出发制定人力资源发展计划。 相似文献