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91.
The genomic RNA patterns of six different bovine rotavirus isolates were analyzed on high-percentage polyacrylamide gels (12.5, 13.6, and 17.5%). In contrast to the RNA patterns exhibited by conventional gel systems, those on the high-percentage gels showed an improvement in segment resolution which consequently aided in the detection of extensive band splitting in these patterns. The ability to clone out various electrophoretically distinct virus subpopulations from each of the six isolates provided an explanation for the band splitting detected by the high-resolution gels. The significance of the coexistence of genetically distinct rotavirus populations within a single host is discussed. 相似文献
92.
IRAK regulates macrophage foam cell formation by modulating genes involved in cholesterol uptake and efflux 下载免费PDF全文
93.
A polyclonal antibody-based antigen-capture ELISA (AC-ELISA) has been developed for detection of Canine parvovirus (CPV) antigens
in faecal samples of dogs. The assay uses rabbit anti-CPV polyclonal antibody as the capture antibody, guinea pig anti-CPV
polyclonal antibody as tracing antibody and anti-guinea pig HRPO conjugate as the detection system. The optimum dilution of
the capture antibody and the tracing antibody capable of detecting the CPV-2 antigens was found to be 1:1 600 and 1:400, respectively,
in the check-board titration. In this study, a total of 152 samples (129 faecal samples and 23 cell culture supernatant) were
tested both by AC-ELISA and by polymerase chain reaction (PCR). Of the samples tested, 69 and 78 samples were found positive
by AC-ELISA and PCR, respectively. The AC-ELISA had relative sensitivity, relative specificity and accuracy of 88.4%, 100.0%
and 91.4% respectively. The analytical sensitivity of AC-ELISA was estimated to be 102.8 TCID50/mL whereas PCR sensitivity was 100.8 TCID50/mL. The AC-ELISA is a simple, quick and reliable method for screening large numbers of faecal samples of dogs suspected of
CPV infection. 相似文献
94.
Much modern work in phylogenetics depends on statistical sampling approaches to phylogeny construction to estimate probability distributions of possible trees for any given input data set. Our theoretical understanding of sampling approaches to phylogenetics remains far less developed than that for optimization approaches, however, particularly with regard to the number of sampling steps needed to produce accurate samples of tree partition functions. Despite the many advantages in principle of being able to sample trees from sophisticated probabilistic models, we have little theoretical basis for concluding that the prevailing sampling approaches do in fact yield accurate samples from those models within realistic numbers of steps. We propose a novel approach to phylogenetic sampling intended to be both efficient in practice and more amenable to theoretical analysis than the prevailing methods. The method depends on replacing the standard tree rearrangement moves with an alternative Markov model in which one solves a theoretically hard but practically tractable optimization problem on each step of sampling. The resulting method can be applied to a broad range of standard probability models, yielding practical algorithms for efficient sampling and rigorous proofs of accurate sampling for heated versions of some important special cases. We demonstrate the efficiency and versatility of the method by an analysis of uncertainty in tree inference over varying input sizes. In addition to providing a new practical method for phylogenetic sampling, the technique is likely to prove applicable to many similar problems involving sampling over combinatorial objects weighted by a likelihood model. 相似文献
95.
Superoxide dismutase: a photochemical augmentation assay. 总被引:21,自引:0,他引:21
Cell envelope vesicles containing bacteriorhodopsin, prepared from Halobacterium halobium, have previously been shown to accumulate glutamate to high concentration gradients when illuminated. This active transport is energized by a sodium gradient (Naout+ ? Nain+), which arises from Na+-efflux coupled to the light-induced H+-gradient. The oxidation of dimethyl phenylenediamine (DPD) by the vesicles also can drive uphill glutamate transport, and such transport is inhibited by KCN, azide, ionophores, or uncouplers. KT for glutamate is 1.4 × 10?7m under these conditions, as compared to 1.3 × 10?7m for light-induced transport. The respiration-induced transport of glutamate is dependent on high Na+ concentrations on the vesicle exterior and requires low Na+ concentrations in the interior. When Na+ of increasing concentrations is included in the vesicles, transport proceeds with increasing lags, similarly to the case of light-driven transport. In vesicles to which DPD is added first, and then KCN at increasing time intervals (5 to 15 min), glutamate transport occurs after the addition of KCN, with increasing rates, even though respiration is inhibited. This indicates that the energy generated by DPD-oxidation is conserved over several minutes. These results suggest that in the case of respiration-dependent glutamate transport the translocation is also driven by a Na+-gradient; thus, there is a single glutamate transport system independent of the source of energy. The generation of such an Na+-gradient during DPD-oxidation implies that the respiration component involved, cytochrome oxidase, is functionally equivalent to bacteriorhodopsin, which acts as a proton pump. 相似文献
96.
The lesser grain borer Rhyzopertha dominica (F.) is one of the most destructive insect pests of stored grain. This pest has been controlled successfully by fumigation with phosphine for the last several decades, though strong resistance to phosphine in many countries has raised concern about the long term usefulness of this control method. Previous genetic analysis of strongly resistant (SR) R. dominica from three widely geographically dispersed regions of Australia, Queensland (SR(QLD)), New South Wales (SR(NSW)) and South Australia (SR(SA)), revealed a resistance allele in the rph1 gene in all three strains. The present study confirms that the rph1 gene contributes to resistance in a fourth strongly resistant strain, SR2(QLD), also from Queensland. The previously described rph2 gene, which interacts synergistically with rph1 gene, confers strong resistance on SR(QLD) and SR(NSW). We now provide strong circumstantial evidence that weak alleles of rph2, together with rph1, contribute to the strong resistance phenotypes of SR(SA) and SR2(QLD). To test the notion that rph1 and rph2 are solely responsible for the strong resistance phenotype of all resistant R. dominica, we created a strain derived by hybridising the four strongly resistant lines. Following repeated selection for survival at extreme rates of phosphine exposure, we found only slightly enhanced resistance. This suggests that a single sequence of genetic changes was responsible for the development of resistance in these insects. 相似文献
97.
Characterization of Mycolytic Enzymes of Bacillus Strains and Their Bio-Protection Role Against Rhizoctonia solani in Tomato 总被引:1,自引:0,他引:1
Solanki MK Robert AS Singh RK Kumar S Pandey AK Srivastava AK Arora DK 《Current microbiology》2012,65(3):330-336
Four antagonists bacteria namely, Bacillus megaterium MB3, B. subtilis MB14, B. subtilis MB99 and B. amyloliquefaciens MB101 were able to produce chitinase, β-1,3-glucanase and protease in different range with the presence of Rhizoctonia solani cell wall as a carbon source. Amplification of chitinase (chiA) gene of 270 bp and β-1, 3-glucanase gene of 415 bp was given supportive evidence at molecular level of antibiosis. After in vitro screening, all antagonists were tested against R. solani under greenhouse conditions. Root treatment of Bacillus strains showed superior defense during pathogen suppression in terms of chitinase, glucanase, peroxidase, poly phenol oxidase, phenylalanine ammonia-lyase activity and total phenolic content in leaves of tomato. All these enzymes accumulated high in tomato leaves as compared to roots. Pathogenesis-related proteins and defense-related enzymes accumulation was directly correlated with plant protection and greenhouse results indicated that B. amyloliquefaciens MB101- and B. subtilis MB14-treated plants offered 69.76 and 61.51 % disease reductions, respectively, over the infected control. These results established that these organisms have the potential to act as biocontrol agents. This study could be highlighted a mutual importance of liquid formulation of antagonistic Bacillus spp. against root associated sclerotia former pathogen R. solani. 相似文献
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Phing-How Lou Eliana Lucchinetti Liyan Zhang Andreas Affolter Manoj Gandhi Martin Hersberger Blair E. Warren Hélène Lemieux Hany F. Sobhi Alexander S. Clanachan Michael Zaugg 《PloS one》2014,9(8)