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921.
Korotkova EA Park R Cherkasova EA Lipskaya GY Chumakov KM Feldman EV Kew OM Agol VI 《Journal of virology》2003,77(23):12460-12465
The global eradication of poliomyelitis will require substantial changes in immunization practices. One of the proposed scenarios includes cessation of vaccination with live oral poliovirus vaccine (OPV) and the creation of an OPV stockpile for emergency response in case of the reintroduction of poliovirus into circulation. We describe here a retrospective analysis of the cessation of OPV usage in a region of the Byelorussian Republic of the former Soviet Union in 1963 to 1966. During this period, a widespread circulation and evolution of independent lineages of vaccine-derived polioviruses took place in the region. Some of these lineages appeared to originate from OPV given to 40 children in the community during this period of essentially no vaccinations. The data demonstrate very high risks associated with both the local cessation of OPV vaccination and the proposed use of OPV to control a possible reemergence of poliovirus in the postvaccination period. The high transmissibility of OPV-derived viruses in nonimmune population, documented here, and the known existence of long-term OPV excretors should be also considered in assessing risks of the synchronized global cessation of OPV usage. 相似文献
922.
Taraban VY Rowley TF Al-Shamkhani A 《Journal of immunology (Baltimore, Md. : 1950)》2004,173(11):6542-6546
The CD154/CD40 interaction is an important pathway of CD4 T cell help for CD8 T cell responses. In this study, we address the role of CD70, a member of the TNF superfamily and the ligand for the T cell costimulatory receptor CD27, in CD40-mediated priming of CD8 T cells. Using an agonistic anti-CD40 mAb to mimic the CD154/CD40 interaction we demonstrate that the priming of OT-I TCR transgenic or endogenous mouse OVA-specific CD8 T cells is critically dependent on CD70/CD27 interaction. CD70 blockade inhibited CD40-mediated clonal expansion of CD8 T cells and reduced the number of memory CD8 T cells generated. Furthermore, CD70 blockade during the initial priming of CD8 T cells inhibited the ability of memory CD8 T cells to expand in response to a second encounter with Ag. Our data indicate that CD70 expression on APCs plays a key role in CD40-dependent CD8 T cell responses. 相似文献
923.
924.
The systematic position of the cestode Hymenolepis blarinae Rausch & Kuns, 1950, a parasite of shrews in North America, is reconsidered. The authors disagree with both Yamaguti (1959), who transferred H. blarinae to the genus Rodentolepis, and Schmidt (1986), who considered Rodentolepis to be a synonym of Vampirolepis and transferred this species to the latter genus. The morphological characters of H. blarinae, such as the shape and number of rostellar hooks, strobila size, the topography of the reproductive organs and the well-defined ornamentation of the cirrus, do not permit the allocation of this species to any known genus of hymenolepidids. Therefore, a new taxon Blarinolepis n. g., is established, with B.blarinae (Rausch & Kuns, 1950) n. comb. as the type-species. A generic diagnosis is presented and morphology of holotype of B. blarinae is redescribed and figured. 相似文献
925.
Vadim Klyushnichenko Alice Bernier Amine Kamen Eef Harmsen 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2001,755(1-2)
We developed a HPLC method on a novel continuous bed matrix (UNO Q, Bio-Rad) for the direct quantification of adenoviral type 5 (Ad5) particles produced in 293S Human Embryonic Kidney cells and compared this with an existing HPLC method on a conventional ion-exchange resin (Resource Q, Pharmacia). The 293S cell extract contained large amounts of DNA. This contaminated the viral peak on the Resource Q column and only after Benzonase treatment was it possible to quantify the viral particles in the cell extract. In contrast, the virus peak on the UNO Q column was resolved from the DNA which eliminates the need for pretreatment of the sample with Benzonase. Cross-analysis of the Ad5 fraction from the UNO Q column using a size-exclusion HPLC column revealed no additional contaminating peaks. We conclude that the purity of the Ad5 virus peak on the continuous bed matrix UNO Q column was superior to the purity of the virus on the conventional Resource Q column, which is essential for reliable quantification. 相似文献
926.
In June–July of 1993 and 1995, pelagic zooplankton dynamics of aglacial lake was investigated. In those years weather conditions
diffferedsubstantially. This resulted not only in a great difference in the watersurface temperature (in 1993, <17.8± 0.47
°C; in 1995, 20.4± 0.33 °C), but also in an increase in the depth of metalimnionzone in 1995 in comparison with 1993. The
ecological efficiency(Ke, the ratio of secondary to primary consumer productions,was 0.28 ± 0.031 in 1993 and 0.21± 0.034 in 1995. The higherKe was accompanied by lowering of spatial structurization,primary and secondary consumer production.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
927.
Landeta O Landajuela A Gil D Taneva S Di Primo C Sot B Valle M Frolov VA Basañez G 《The Journal of biological chemistry》2011,286(10):8213-8230
BAK is a key effector of mitochondrial outer membrane permeabilization (MOMP) whose molecular mechanism of action remains to be fully dissected in intact cells, mainly due to the inherent complexity of the intracellular apoptotic machinery. Here we show that the core features of the BAK-driven MOMP pathway can be reproduced in a highly simplified in vitro system consisting of recombinant human BAK lacking the carboxyl-terminal 21 residues (BAKΔC) and tBID in combination with liposomes bearing an appropriate lipid environment. Using this minimalist reconstituted system we established that tBID suffices to trigger BAKΔC membrane insertion, oligomerization, and pore formation. Furthermore, we demonstrate that tBID-activated BAKΔC permeabilizes the membrane by forming structurally dynamic pores rather than a large proteinaceous channel of fixed size. We also identified two distinct roles played by mitochondrial lipids along the molecular pathway of BAKΔC-induced membrane permeabilization. First, using several independent approaches, we showed that cardiolipin directly interacts with BAKΔC, leading to a localized structural rearrangement in the protein that "primes" BAKΔC for interaction with tBID. Second, we provide evidence that selected curvature-inducing lipids present in mitochondrial membranes specifically modulate the energetic expenditure required to create the BAKΔC pore. Collectively, our results support the notion that BAK functions as a direct effector of MOMP akin to BAX and also adds significantly to the growing evidence indicating that mitochondrial membrane lipids are actively implicated in BCL-2 protein family function. 相似文献
928.
Marina V. Kasaikina Dmitri E. Fomenko Vyacheslav M. Labunskyy Salil A. Lachke Wenya Qiu Juliet A. Moncaster Jie Zhang Mark W. Wojnarowicz Jr. Sathish Kumar Natarajan Mikalai Malinouski Ulrich Schweizer Petra A. Tsuji Bradley A. Carlson Richard L. Maas Marjorie F. Lou Lee E. Goldstein Dolph L. Hatfield Vadim N. Gladyshev 《The Journal of biological chemistry》2011,286(38):33203-33212
The 15-kDa selenoprotein (Sep15) is a thioredoxin-like, endoplasmic reticulum-resident protein involved in the quality control of glycoprotein folding through its interaction with UDP-glucose:glycoprotein glucosyltransferase. Expression of Sep15 is regulated by dietary selenium and the unfolded protein response, but its specific function is not known. In this study, we developed and characterized Sep15 KO mice by targeted removal of exon 2 of the Sep15 gene coding for the cysteine-rich UDP-glucose:glycoprotein glucosyltransferase-binding domain. These KO mice synthesized a mutant mRNA, but the shortened protein product could be detected neither in tissues nor in Sep15 KO embryonic fibroblasts. Sep15 KO mice were viable and fertile, showed normal brain morphology, and did not activate endoplasmic reticulum stress pathways. However, parameters of oxidative stress were elevated in the livers of these mice. We found that Sep15 mRNA was enriched during lens development. Further phenotypic characterization of Sep15 KO mice revealed a prominent nuclear cataract that developed at an early age. These cataracts did not appear to be associated with severe oxidative stress or glucose dysregulation. We suggest that the cataracts resulted from an improper folding status of lens proteins caused by Sep15 deficiency. 相似文献
929.
Klenchin VA Frye JJ Jones MH Winey M Rayment I 《The Journal of biological chemistry》2011,286(20):18240-18250
The spindle pole body of the budding yeast Saccharomyces cerevisiae has served as a model system for understanding microtubule organizing centers, yet very little is known about the molecular structure of its components. We report here the structure of the C-terminal domain of the core component Cnm67 at 2.3 Å resolution. The structure determination was aided by a novel approach to crystallization of proteins containing coiled-coils that utilizes globular domains to stabilize the coiled-coils. This enhances their solubility in Escherichia coli and improves their crystallization. The Cnm67 C-terminal domain (residues Asn-429—Lys-581) exhibits a previously unseen dimeric, interdigitated, all α-helical fold. In vivo studies demonstrate that this domain alone is able to localize to the spindle pole body. In addition, the structure reveals a large functionally indispensable positively charged surface patch that is implicated in spindle pole body localization. Finally, the C-terminal eight residues are disordered but are critical for protein folding and structural stability. 相似文献
930.
Gottar-Guillier M Dodeller F Huesken D Iourgenko V Mickanin C Labow M Gaveriaux S Kinzel B Mueller M Alitalo K Littlewood-Evans A Cenni B 《Journal of immunology (Baltimore, Md. : 1950)》2011,186(10):6014-6023
Inflammatory cytokines like TNF play a central role in autoimmune disorders such as rheumatoid arthritis. We identified the tyrosine kinase bone marrow kinase on chromosome X (BMX) as an essential component of a shared inflammatory signaling pathway. Transient depletion of BMX strongly reduced secretion of IL-8 in cell lines and primary human cells stimulated by TNF, IL-1β, or TLR agonists. BMX was required for phosphorylation of p38 MAPK and JNK, as well as activation of NF-κB. The following epistasis analysis indicated that BMX acts downstream of or at the same level as the complex TGF-β activated kinase 1 (TAK1)-TAK1 binding protein. At the cellular level, regulation of the IL-8 promoter required the pleckstrin homology domain of BMX, which could be replaced by an ectopic myristylation signal, indicating a requirement for BMX membrane association. In addition, activation of the IL-8 promoter by in vitro BMX overexpression required its catalytic activity. Genetic ablation of BMX conferred protection in the mouse arthritis model of passive K/BxN serum transfer, confirming that BMX is an essential mediator of inflammation in vivo. However, genetic replacement with a catalytically inactive BMX allele was not protective in the same arthritis animal model. We conclude that BMX is an essential component of inflammatory cytokine signaling and that catalytic, as well as noncatalytic functions of BMX are involved. 相似文献