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Brigitta M. N. Brinkman Eric L. Kaijzel Tom W. J. Huizinga Marius J. Giphart Ferdinand C. Breedveld Cornelis L. Verweij 《Human genetics》1995,96(4):493-493
We have identified a C-insertion polymorphism in the 5'UTR of the first exon of the human tumor necrosis factor alpha (TNFA) gene. TNFA is a cytokine that plays an important role in the inflammatory response. 相似文献
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Tiffany M. Tsang Jeffrey S. Wiese Suleyman Felek Malte Kronshage Eric S. Krukonis 《PloS one》2013,8(12)
The Yersinia pestis adhesin Ail mediates host cell binding and facilitates delivery of cytotoxic Yop proteins. Ail from Y. pestis and Y. pseudotuberculosis is identical except for one or two amino acids at positions 43 and 126 depending on the Y. pseudotuberculosis strain. Ail from Y. pseudotuberculosis strain YPIII has been reported to lack host cell binding ability, thus we sought to determine which amino acid difference(s) are responsible for the difference in cell adhesion. Y. pseudotuberculosis YPIII Ail expressed in Escherichia coli bound host cells, albeit at ∼50% the capacity of Y. pestis Ail. Y. pestis Ail single mutants, Ail-E43D and Ail-F126V, both have decreased adhesion and invasion in E. coli when compared to wild-type Y. pestis Ail. Y. pseudotuberculosis YPIII Ail also had decreased binding to the Ail substrate fibronectin, relative to Y. pestis Ail in E. coli. When expressed in Y. pestis, there was a 30–50% decrease in adhesion and invasion depending on the substitution. Ail-mediated Yop delivery by both Y. pestis Ail and Y. pseudotuberculosis Ail were similar when expressed in Y. pestis, with only Ail-F126V giving a statistically significant reduction in Yop delivery of 25%. In contrast to results in E. coli and Y. pestis, expression of Ail in Y. pseudotuberculosis led to no measurable adhesion or invasion, suggesting the longer LPS of Y. pseudotuberculosis interferes with Ail cell-binding activity. Thus, host context affects the binding activities of Ail and both Y. pestis and Y. pseudotuberculosis Ail can mediate cell binding, cell invasion and facilitate Yop delivery. 相似文献
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Eric J. Engstrom Ph. D. 《PSN》2003,1(1):53-61
Recent studies on Emil Kraepelin’s experimental work have focused on the relationship between the psychological experiment and his nosological delineation of dementia praecox and manic-depressive disorders. Interpreters have argued variously that the psychological experiment had either no influence on the nosology, or that it was the very precondition of the nosology, or that it biased the nosology in favor of organic disorders. This article calls into question this historiographic affiliation of experiment and nosology. It argues that by framing Kraepelin’s experimental research agenda solely in terms of his nosology, interpreters have overlooked other important personal, institutional, diagnostic, and professional motives governing that research. Kraepelin’s early career crisis, his frustrations working in overcrowded institutions, and his efforts to enhance the professional stature of psychiatry all influenced his experimental research agenda of amessende Individualpsychologie and the historical significance of that agenda in Kraepelinian psychiatry. 相似文献
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Martin Bundi Mohammad Monir Shah Eric Odoyo Cyrus Kathiiko Ernest Wandera Gabriel Miring'u Sora Guyo Daniel Langat Kouichi Morita Yoshio Ichinose 《Microbiology and immunology》2019,63(9):350-358
Kenya is endemic for cholera with different waves of outbreaks having been documented since 1971. In recent years, new variants of Vibrio cholerae O1 have emerged and have replaced most of the traditional El Tor biotype globally. These strains also appear to have increased virulence, and it is important to describe and document their phenotypic and genotypic traits. This study characterized 146 V. cholerae O1 isolates from cholera outbreaks that occurred in Kenya between 1975 and 2017. Our study reports that the 1975–1984 strains had typical classical or El Tor biotype characters. New variants of V. cholerae O1 having traits of both classical and El Tor biotypes were observed from 2007 with all strains isolated between 2015 and 2017 being sensitive to polymyxin B and carrying both classical and El Tor type ctxB. All strains were resistant to Phage IV and harbored rstR, rtxC, hlyA, rtxA and tcpA genes specific for El Tor biotype indicating that the strains had an El Tor backbone. Pulsed field gel electrophoresis (PFGE) genotyping differentiated the isolates into 14 pulsotypes. The clustering also corresponded with the year of isolation signifying that the cholera outbreaks occurred as separate waves of different genetic fingerprints exhibiting different genotypic and phenotypic characteristics. The emergence and prevalence of V. cholerae O1 strains carrying El Tor type and classical type ctxB in Kenya are reported. These strains have replaced the typical El Tor biotype in Kenya and are potentially more virulent and easily transmitted within the population. 相似文献
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M. R. Duvall 《Plant Systematics and Evolution》2001,228(3-4):143-152
Critical morphological synapomorphies have not been found in support of the Acoranan hypothesis, the molecular phylogenetic
discovery that Acoranae are the basal monocots. The previously undetermined pattern of anther wall development in Acorus has been suggested to be one such character. Two main types of anther wall development have been recognized: 1) the “monocotyledonous”
type, which characterizes both monocots and dicots, and 2) the “dicotyledonous” type, which is almost exclusively found among
dicots. An anatomical study of anther wall development in Acorus was here undertaken using the electron microscope. Development of the anther wall in Acorus was found to be somewhat irregular or perhaps even intermediate between the two types although largely consistent with the
“monocotyledonous” type. The presumed significance of anther wall development and other critical morphological characters
to the Acoranan hypothesis in the absence of knowledge about the sister group to the monocots is evaluated.
Received August 28, 2000 Accepted February 19, 2001 相似文献
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