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991.
H Li EG Rhee K Masek-Hammerman JE Teigler P Abbink DH Barouch 《Journal of virology》2012,86(19):10862-10865
The cellular receptor utilized by adenovirus serotype 26 (Ad26) has remained unclear. Here we show that Ad26 transduction is CD46-dependent and is efficiently blocked by anti-CD46 but not anti-CAR antibodies, demonstrating that Ad26 utilizes CD46 as a primary cellular receptor. Moreover, following Ad26 vaccination of rhesus monkeys, we did not observe sustained activation of peripheral or mucosal vector-specific CD4(+) T lymphocytes. These data contribute to our understanding of Ad26 as a candidate vaccine vector. 相似文献
992.
A comprehensive vaccine for human immunodeficiency virus type 1 (HIV-1) would block HIV-1 acquisition as well as durably control viral replication in breakthrough infections. Recent studies have demonstrated that Env is required for a vaccine to protect against acquisition of simian immunodeficiency virus (SIV) in vaccinated rhesus monkeys, but the antigen requirements for virologic control remain unclear. Here, we investigate whether CD8(+) T lymphocytes from vaccinated rhesus monkeys mediate viral inhibition in vitro and whether these responses predict virologic control following SIV challenge. We observed that CD8(+) lymphocytes from 23 vaccinated rhesus monkeys inhibited replication of SIV in vitro. Moreover, the magnitude of inhibition prior to challenge was inversely correlated with set point SIV plasma viral loads after challenge. In addition, CD8 cell-mediated viral inhibition in vaccinated rhesus monkeys correlated significantly with Gag-specific, but not Pol- or Env-specific, CD4(+) and CD8(+) T lymphocyte responses. These findings demonstrate that in vitro viral inhibition following vaccination largely reflects Gag-specific cellular immune responses and correlates with in vivo virologic control following infection. These data suggest the importance of including Gag in an HIV-1 vaccine in which virologic control is desired. 相似文献
993.
Jiao P Cao L Yuan R Wei L Song Y Shen D Gong L Luo K Ren T Liao M 《Journal of virology》2012,86(14):7716
An H10N8 avian influenza virus (AIV), designated A/Duck/Guangdong/E1/2012 (H10N8), was isolated from a duck in January 2012. This is first report that this subtype of AIV was isolated from a live bird market (LBM) in Guangdong Province in southern China. Furthermore, the complete genome of this strain was analyzed. The availability of genome sequences is helpful to further investigations of epidemiology and molecular characteristics of AIV in southern China. 相似文献
994.
Kathryn E. Stephenson Adam SanMiguel Nathaniel L. Simmons Kaitlin Smith Mark G. Lewis James J. Szinger Bette Korber Dan H. Barouch 《Journal of virology》2012,86(21):11434-11440
A global HIV-1 vaccine will likely need to induce immune responses against conserved HIV-1 regions to contend with the profound genetic diversity of HIV-1. Here we evaluated the capacity of immunogens consisting of only highly conserved HIV-1 sequences that are aimed at focusing cellular immune responses on these potentially critical regions. We assessed in rhesus monkeys the breadth and magnitude of T lymphocyte responses elicited by adenovirus vectors expressing either full-length HIV-1 Gag/Pol/Env immunogens or concatenated immunogens consisting of only highly conserved HIV-1 sequences. Surprisingly, we found that the full-length immunogens induced comparable breadth (P = 1.0) and greater magnitude (P = 0.01) of CD8+ T lymphocyte responses against conserved HIV-1 regions compared with the conserved-region-only immunogens. Moreover, the full-length immunogens induced a 5-fold increased total breadth of HIV-1-specific T lymphocyte responses compared with the conserved-region-only immunogens (P = 0.007). These results suggest that full-length HIV-1 immunogens elicit a substantially increased magnitude and breadth of cellular immune responses compared with conserved-region-only HIV-1 immunogens, including greater magnitude and comparable breadth of responses against conserved sequences. 相似文献
995.
Bruna Comparsi Daiane F. Meinerz Jeferson L. Franco Thaís Posser Alessandro de Souza Prestes Sílvio Terra Stefanello Danúbia B. dos Santos Caroline Wagner Marcelo Farina Michael Aschner Alcir L. Dafre Jo?o B. T. Rocha 《Molecular and cellular biochemistry》2012,370(1-2):173-182
In this study, we investigated the effect of diphenyl ditelluride (PhTe)2 administration (10 and 50?μmol/kg) on adult mouse behavioral performance as well as several parameters of oxidative stress in the brain and liver. Adult mice were injected with (PhTe)2 or canola oil subcutaneously (s.c.) daily for 7?days. Results demonstrated that (PhTe)2 induced prominent signs of toxicity (body weight loss), behavioral alterations and increased in lipid peroxidation in brain. 50?μmol/kg (PhTe)2 inhibited blood δ-aminolevulinic acid dehydratase (δ-ALA-D), a redox sensitive enzyme. (PhTe)2 caused an increase in cerebral non-protein thiol (NPSH) and protein thiol (PSH) groups. In the liver, 50?μmol/kg (PhTe)2 decreased NPSH, but did not alter the content of protein thiol groups. (PhTe)2 decreased cerebral antioxidant enzymes (catalase (CAT), superoxide dismutase (SOD), glutathione reductase (GR), glutathione peroxidase (GPx), and thioredoxin reductase (TrxR). In liver, (PhTe)2 increase SOD and GR and decreased GPx activity. Results obtained herein suggest that the brain was more susceptible to oxidative stress induced by (PhTe)2 than the liver. Furthermore, we have demonstrated for the first time that TrxR is an in vivo target for (PhTe)2. Combined, these results highlight a novel molecular mechanism involved in the toxicity of (PhTe)2. In particular the inhibition of important selenoenzymes (TrxR and GPx) seems to be involved in the neurotoxicity associated with (PhTe)2 exposure in adult mice. 相似文献
996.
Yuan Z Chu G Dan Y Li J Zhang L Gao X Gao H Li J Xu S Liu Z 《Molecular biology reports》2012,39(6):6625-6631
Bovine mastitis is a very complex and common disease of dairy cattle and a major source of economic losses to the dairy industry
worldwide. In this study, the bovine breast cancer 1, early onset gene (BRCA1) was taken as a candidate gene for mastitis resistance. The main object of this study was to investigate whether the BRCA1 gene was associated with mastitis in cattle. Through DNA sequencing, Polymerase Chain Reaction-Restriction Fragment Length
Polymorphism (PCR-RFLP) and Created Restriction Site PCR (CRS-PCR) methods, three SNPs (G22231T, T25025A, and C28300A) were
detected and twenty-four combinations of these SNPs were observed. The single SNP and their genetic effects on somatic cell
score (SCS) were evaluated and a significant association with SCS was found in C28300A. The mean of genotype EE was significantly
lower than those of genotypes EF and FF. The results of combined genotypes analysis of three SNPs showed that BBDDFF genotype
with the highest SCS were easily for the mastitis susceptibility, whereas AACCEE genotype with the lowest SCS were favorable
for the mastitis resistance. The information provided in the present study will be very useful for improving mastitis resistance
in dairy cattle by marker-assisted selection. 相似文献
997.
Stasiak ME Wiznia D Alzoobaee S Ciccotti MC Imhauser CW Voigt C Torzilli PA Deng XH Rodeo SA 《Journal of biomechanical engineering》2012,134(4):041008
We designed and validated a novel device for applying flexion-extension cycles to a rat knee in an in vivo model of anterior cruciate ligament reconstruction (ACL-R). Our device is intended to simulate rehabilitation motion and exercise post ACL-R to optimize physical rehabilitation treatments for the improved healing of tendon graft ligament reconstructions. The device was validated for repeatability of the knee kinematic motion by measuring the force versus angular rotation response from repeated trials using cadaver rats. The average maximum force required for rotating an ACL reconstructed rat knee through 100 degrees of flexion-extension was 0.4 N with 95% variability for all trials within ±0.1 N. 相似文献
998.
Previous report has shown that the expression of recombinant human consensus interferon-α mutant (cIFN) in Pichia pastoris in bioreactor is limited with respect to the incorrectly folded cIFN with incomplete disulfide bond, which lead to the degradation and aggregation of cIFN. In this study, the origin of incorrectly folded cIFN is firstly studied. Fed-batch fermentation in bioreactor shows that the incorrectly folded cIFN is formed intramolecularly and secreted to the extracellular environment. Further chemostat cultures indicate that the specific growth rate is the critical factor for the production of incorrect cIFN. In addition, cell shows reduced expression level of cIFN at high specific growth rate. We also demonstrate that the incorrectly folded cIFN could form aggregates intracellularly and these aggregates are non-covalent forms. Taken together, these results suggest that the efficient heterologous expression of cIFN is limited by high cell growth that is unique from expression limitations seen for soluble proteins. A balance has to be found between the increase for high efficient expression of heterologous proteins and requirement of the high cell growth during the expression of recombinant proteins in P. pastoris. 相似文献
999.
Li D Rothballer M Engel M Hoser J Schmidt T Kuttler C Schmid M Schloter M Hartmann A 《FEMS microbiology ecology》2012,79(3):751-762
Acidovorax radicis N35, isolated from surface-sterilized wheat roots (Triticum aestivum), showed irreversible phenotypic variation in nutrient broth, resulting in a differing colony morphology. In addition to the wild-type form (rough colony type), a phenotypic variant form (smooth colony type) appeared at a frequency of 3.2?×?10(-3) per cell per generation on NB agar plates. In contrast to the N35 wild type, the variant N35v showed almost no cell aggregation and had lost its flagella and swarming ability. After inoculation, only the wild-type N35 significantly promoted the growth of soil-grown barley plants. After co-inoculation of axenically grown barley seedlings with differentially fluorescently labeled N35 and N35v cells, decreased competitive endophytic root colonization in the phenotypic variant N35v was observed using confocal laser scanning microscopy. In addition, 454 pyrosequencing of both phenotypes revealed almost identical genomic sequences. The only stable difference noted in the sequence of the phenotype variant N35v was a 16-nucleotide deletion identified in a gene encoding the mismatch repair protein MutL. The deletion resulted in a frameshift that revealed a new stop codon resulting in a truncated MutL protein missing a functional MutL C-terminal domain. The mutation was consistent in all investigated phenotype variant cultures and might be responsible for the observed phenotypic variation in A.?radicis N35. 相似文献
1000.
Warren DL 《Trends in ecology & evolution》2012,27(9):497-500
There is a growing awareness of problems with the estimation of the ecological tolerances of species through correlative modeling approaches. These problems have led some investigators to argue for abandoning terms such as 'ecological niche model' and 'environmental niche model' in favor of the ostensibly more value-neutral 'species distribution model', as the models are thought to frequently be poor estimators of the niche. Here, I argue that most applications to which these models are put require the assumption that they do estimate the niche, however imperfectly, and that obscuring this inescapable and potentially flawed assumption in the terminology may only serve to hinder the development of the field. 相似文献