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Jung-Seok Lee Vittal Mogasale Jacqueline K. Lim Mabel Carabali Chukiat Sirivichayakul Dang Duc Anh Kang-Sung Lee Vu Dinh Thiem Kriengsak Limkittikul Le Huu Tho Ivan D. Velez Jorge E. Osorio Pornthep Chanthavanich Luiz J. da Silva Brian A. Maskery 《PLoS neglected tropical diseases》2015,9(6)
BackgroundThe rise in dengue fever cases and the absence of dengue vaccines will likely cause governments to consider various types of effective means for controlling the disease. Given strong public interests in potential dengue vaccines, it is essential to understand the private economic benefits of dengue vaccines for accelerated introduction of vaccines into the public sector program and private markets of high-risk countries.Conclusions/SignificanceKnowing that dengue vaccines are not yet available, our study provides critical information to both public and private sectors. The study results can be used to ensure broad coverage with an affordable price and incorporated into cost benefit analyses, which can inform prioritization of alternative health interventions at the national level. 相似文献
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Bourgogne A Garsin DA Qin X Singh KV Sillanpaa J Yerrapragada S Ding Y Dugan-Rocha S Buhay C Shen H Chen G Williams G Muzny D Maadani A Fox KA Gioia J Chen L Shang Y Arias CA Nallapareddy SR Zhao M Prakash VP Chowdhury S Jiang H Gibbs RA Murray BE Highlander SK Weinstock GM 《Genome biology》2008,9(7):R110-16
Background
Enterococcus faecalis has emerged as a major hospital pathogen. To explore its diversity, we sequenced E. faecalis strain OG1RF, which is commonly used for molecular manipulation and virulence studies.Results
The 2,739,625 base pair chromosome of OG1RF was found to contain approximately 232 kilobases unique to this strain compared to V583, the only publicly available sequenced strain. Almost no mobile genetic elements were found in OG1RF. The 64 areas of divergence were classified into three categories. First, OG1RF carries 39 unique regions, including 2 CRISPR loci and a new WxL locus. Second, we found nine replacements where a sequence specific to V583 was substituted by a sequence specific to OG1RF. For example, the iol operon of OG1RF replaces a possible prophage and the vanB transposon in V583. Finally, we found 16 regions that were present in V583 but missing from OG1RF, including the proposed pathogenicity island, several probable prophages, and the cpsCDEFGHIJK capsular polysaccharide operon. OG1RF was more rapidly but less frequently lethal than V583 in the mouse peritonitis model and considerably outcompeted V583 in a murine model of urinary tract infections.Conclusion
E. faecalis OG1RF carries a number of unique loci compared to V583, but the almost complete lack of mobile genetic elements demonstrates that this is not a defining feature of the species. Additionally, OG1RF's effects in experimental models suggest that mediators of virulence may be diverse between different E. faecalis strains and that virulence is not dependent on the presence of mobile genetic elements. 相似文献64.
Horowitz JC Rogers DS Sharma V Vittal R White ES Cui Z Thannickal VJ 《Cellular signalling》2007,19(4):761-771
Transforming growth factor-beta (TGF-beta) is a prototypical tumour-suppressor cytokine with cytostatic and pro-apoptotic effects on most target cells; however, mechanisms of its pro-survival/anti-apoptotic signalling in certain cell types and contexts remain unclear. In human lung fibroblasts, TGF-beta1 is known to induce myofibroblast differentiation in association with the delayed activation of focal adhesion kinase (FAK) and protein kinase B (PKB/AKT). Here, we demonstrate that FAK and AKT are independently regulated by early activation of SMAD3 and p38 MAPK, respectively. Pharmacologic or genetic approaches that disrupt SMAD3 signalling block TGF-beta1-induced activation of FAK, but not AKT; in contrast, disruption of early p38 MAPK signalling abrogates AKT activation, but does not alter FAK activation. TGF-beta1 is able to activate AKT in cells expressing mutant FAK or in cells treated with an RGD-containing peptide that interferes with integrin signalling, inhibits FAK activation and induces anoikis (apoptosis induced by loss of adhesion signalling). TGF-beta1 protects myofibroblasts from anoikis, in part, by activation of the PI3K-AKT pathway. Thus, TGF-beta1 co-ordinately and independently activates the FAK and AKT protein kinase pathways to confer an anoikis-resistant phenotype to myofibroblasts. Activation of these pro-survival/anti-anoikis pathways in myofibroblasts likely contributes to essential roles of TGF-beta1 in tissue fibrosis and tumour-promotion. 相似文献
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Iannucci Jaclyn Rao Haripriya Vittal Grammas Paula 《Cellular and molecular neurobiology》2022,42(4):985-996
Cellular and Molecular Neurobiology - Diabetes is strongly linked to the development of Alzheimer’s disease (AD), though the mechanisms for this enhanced risk are unclear. Because vascular... 相似文献
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The reactivity of [Pt2(μ-S)2(PPh3)4] towards a range of nickel(II) complexes has been probed using electrospray ionisation mass spectrometry coupled with synthesis and characterisation in selected systems. Reaction of [Pt2(μ-S)2(PPh3)4] with [Ni(NCS)2(PPh3)2] gives [Pt2(μ-S)2(PPh3)4Ni(NCS)(PPh3)]+, isolated as its BPh4 − salt; the same product is obtained in the reaction of [Pt2(μ-S)2(PPh3)4] with [NiBr2(PPh3)2] and KNCS. An X-ray structure determination reveals the expected sulfide-bridged structure, with an N-bonded thiocyanate ligand and a square-planar coordination geometry about nickel. A range of nickel(II) complexes NiL2, containing β-diketonate, 8-hydroxyquinolinate, or salicylaldehyde oximate ligands react similarly, giving [Pt2(μ-S)2(PPh3)4NiL]+ cations. 相似文献
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David B. Goodin Vittal K. Yachandra R. David Britt Kenneth Sauer Melvin P. Klein 《BBA》1984,767(2):209-216
Photosynthetic water oxidation by higher plants proceeds as though five intermediates, S0-S4, operate in a cyclic fashion. In this study of the manganese involvement in the process, a low temperature EPR signal is used as an indicator of S-state composition for manganese X-ray absorption K-edge measurements of a spinach Photosystem II preparation. A dramatic change is observed in the edge properties between samples prepared in states S1 and either S2 or S3, establishing a direct relation between the local environment of Mn and the S-state composition. Samples in S2 or S3 exhibit a broadening of the principal absorption peak and a shift to higher energy by as much as 2.5 eV relative to S1 samples. The magnitude of these changes is directly related to the EPR signal intensity induced by illumination. Models are discussed in which these data may be interpreted in terms of a conformation-induced change in Mn ligation and/or oxidation during the S1 to S2 transition. 相似文献
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Srinivasa Vittal Katikireddi 《BMJ (Clinical research ed.)》2004,328(7449):1190-1193
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Ruchira Chatterjee Louise Lassalle Sheraz Gul Franklin D. Fuller Iris D. Young Mohamed Ibrahim Casper de Lichtenberg Mun Hon Cheah Athina Zouni Johannes Messinger Vittal K. Yachandra Jan Kern Junko Yano 《Physiologia plantarum》2019,166(1):60-72
In nature, an oxo‐bridged Mn4CaO5 cluster embedded in photosystem II (PSII), a membrane‐bound multi‐subunit pigment protein complex, catalyzes the water oxidation reaction that is driven by light‐induced charge separations in the reaction center of PSII. The Mn4CaO5 cluster accumulates four oxidizing equivalents to enable the four‐electron four‐proton catalysis of two water molecules to one dioxygen molecule and cycles through five intermediate S‐states, S0 – S4 in the Kok cycle. One important question related to the catalytic mechanism of the oxygen‐evolving complex (OEC) that remains is, whether structural isomers are present in some of the intermediate S‐states and if such equilibria are essential for the mechanism of the O‐O bond formation. Here we compare results from electron paramagnetic resonance (EPR) and X‐ray absorption spectroscopy (XAS) obtained at cryogenic temperatures for the S2 state of PSII with structural data collected of the S1, S2 and S3 states by serial crystallography at neutral pH (~6.5) using an X‐ray free electron laser at room temperature. While the cryogenic data show the presence of at least two structural forms of the S2 state, the room temperature crystallography data can be well‐described by just one S2 structure. We discuss the deviating results and outline experimental strategies for clarifying this mechanistically important question. 相似文献