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991.
Noninvasive faecal DNA sampling has the potential to provide a wealth of information necessary for monitoring and managing endangered species while eliminating the need to capture, handle or observe rare individuals. However, scoring problems, and subsequent genotyping errors, associated with this monitoring method remain a great concern as they can lead to misidentification of individuals and biased estimates. We examined a kit fox scat data set (353 scats; 80 genotypes) for genotyping errors using both genetic and GIS analyses, and evaluated the feasibility of combining both approaches to assess reliability of the faecal DNA results. We further checked the appropriateness of using faecal genotypes to study kit fox populations by describing information about foxes that we could deduce from the 'acceptable' scat genotypes, and comparing it to information gathered with traditional field techniques. Overall, genetic tests indicated that our data set had a low rate of genotyping error. Furthermore, examination of distributions of scat locations confirmed our data set was relatively error free. We found that analysing information on sex primer consistency and scat locations provided a useful assessment of scat genotype error, and greatly limited the amount of additional laboratory work that was needed to identify potentially 'false' scores. 'Acceptable' scat genotypes revealed information on sex ratio, relatedness, fox movement patterns, latrine use, and size of home range. Results from genetic and field data were consistent, supporting the conclusion that our data set had a very low rate of genotyping error and that this noninvasive method is a reliable approach for monitoring kit foxes. 相似文献
992.
Plasmodium vivax invasion of human erythrocytes requires that the ligand domain of the Duffy-binding protein (DBP) recognize its cognate erythrocyte receptor, making DBP a potential target for therapy. The recently determined crystal structure of the orthologous DBP ligand domain of the closely related simian malaria parasite Plasmodium knowlesi provides insight into the molecular basis for receptor recognition and raises important questions about the mechanism of immune evasion employed by the malaria parasite. 相似文献
993.
Aims were to estimate the extent of genetic heterogeneity in environmental variance. Data comprised 99 535 records of 35-day body weights from broiler chickens reared in a controlled environment. Residual variance within dam families was estimated using ASREML, after fitting fixed effects such as genetic groups and hatches, for each of 377 genetically contemporary sires with a large number of progeny (> 100 males or females each). Residual variance was computed separately for male and female offspring, and after correction for sampling, strong evidence for heterogeneity was found, the standard deviation between sires in within variance amounting to 15–18% of its mean. Reanalysis using log-transformed data gave similar results, and elimination of 2–3% of outlier data reduced the heterogeneity but it was still over 10%. The correlation between estimates for males and females was low, however. The correlation between sire effects on progeny mean and residual variance for body weight was small and negative (-0.1). Using a data set bigger than any yet presented and on a trait measurable in both sexes, this study has shown evidence for heterogeneity in the residual variance, which could not be explained by segregation of major genes unless very few determined the trait. 相似文献
994.
Walter Jaoko Etienne Karita Kayitesi Kayitenkore Gloria Omosa-Manyonyi Susan Allen Soe Than Elizabeth M. Adams Barney S. Graham Richard A. Koup Robert T. Bailer Carol Smith Len Dally Bashir Farah Omu Anzala Claude M. Muvunyi Jean Bizimana Tony Tarragona-Fiol Philip J. Bergin Peter Hayes Martin Ho Kelley Loughran Wendy Komaroff Gwynneth Stevens Helen Thomson Mark J. Boaz Josephine H. Cox Claudia Schmidt Jill Gilmour Gary J. Nabel Patricia Fast Job Bwayo 《PloS one》2010,5(9)
Background
We conducted a double-blind, randomized, placebo-controlled Phase I study of a recombinant replication-defective adenovirus type 5 (rAd5) vector expressing HIV-1 Gag and Pol from subtype B and Env from subtypes A, B and C, given alone or as boost following a DNA plasmid vaccine expressing the same HIV-1 proteins plus Nef, in 114 healthy HIV-uninfected African adults.Methodology/Principal Findings
Volunteers were randomized to 4 groups receiving the rAd5 vaccine intramuscularly at dosage levels of 1×1010 or 1×1011 particle units (PU) either alone or as boost following 3 injections of the DNA vaccine given at 4 mg/dose intramuscularly by needle-free injection using Biojector® 2000. Safety and immunogenicity were evaluated for 12 months. Both vaccines were well-tolerated. Overall, 62% and 86% of vaccine recipients in the rAd5 alone and DNA prime - rAd5 boost groups, respectively, responded to the HIV-1 proteins by an interferon-gamma (IFN-γ) ELISPOT. The frequency of immune responses was independent of rAd5 dosage levels. The highest frequency of responses after rAd5 alone was detected at 6 weeks; after DNA prime - rAd5 boost, at 6 months (end of study). At baseline, neutralizing antibodies against Ad5 were present in 81% of volunteers; the distribution was similar across the 4 groups. Pre-existing immunity to Ad5 did not appear to have a significant impact on reactogenicity or immune response rates to HIV antigens by IFN-γ ELISPOT. Binding antibodies against Env were detected in up to 100% recipients of DNA prime - rAd5 boost. One volunteer acquired HIV infection after the study ended, two years after receipt of rAd5 alone.Conclusions/Significance
The HIV-1 rAd5 vaccine, either alone or as a boost following HIV-1 DNA vaccine, was well-tolerated and immunogenic in African adults. DNA priming increased the frequency and magnitude of cellular and humoral immune responses, but there was no effect of rAd5 dosage on immunogenicity endpoints.Trial Registration
ClinicalTrials.gov NCT00124007相似文献995.
996.
997.
Amanda Maestre Carlos Muskus Victoria Duque Olga Agudelo Pu Liu Akihide Takagi Francis B. Ntumngia John H. Adams Kim Lee Sim Stephen L. Hoffman Giampietro Corradin Ivan D. Velez Ruobing Wang 《PloS one》2010,5(7)
Background
Polymorphism of the Duffy Antigen Receptor for Chemokines (DARC) is associated with susceptibility to and the severity of Plasmodium vivax malaria in humans. P. vivax uses DARC to invade erythrocytes. Individuals lacking DARC are ‘resistant’ to P. vivax erythrocytic infection. However, susceptibility to P. vivax in DARC+ individuals is reported to vary between specific DARC genotypes. We hypothesized that the natural acquisition of antibodies to P. vivax blood stages may vary with the host genotype and the level of DARC expression. Furthermore, high parasitemia has been reported to effect the acquisition of immunity against pre-erythrocytic parasites. We investigated the correlation between host DARC genotypes and the frequency and magnitude of antibodies against P. vivax erythrocytic stage antigens.Methodology/Findings
We assessed the frequencies and magnitudes of antibody responses against P. vivax and P. falciparum sporozoite and erythrocytic antigens in Colombian donors from malaria-endemic regions. The frequency and level of naturally-acquired antibodies against the P. vivax erythrocytic antigens merozoite surface protein 1 (PvMSP1) and Duffy binding protein (PvDBP) varied with the host DARC genotypes. Donors with one negative allele (FY*B/FY*Bnull and FY*A/FY*Bnull) were more likely to have anti-PvMSP1 and anti-PvDBP antibodies than those with two positive alleles (FY*B/FY*B and FY*A/FY*B). The lower IgG3 and IgG1 components of the total IgG response may account for the decreased responses to P. vivax erythrocytic antigens with FY*A/FY*B and FY*B/FY*B genotypes. No such association was detected with P. falciparum erythrocytic antigens, which does not use DARC for erythrocyte invasion.Conclusion/Significance
Individuals with higher DARC expression, which is associated with higher susceptibility to P. vivax infection, exhibited low frequencies and magnitudes of P. vivax blood-stage specific antibody responses. This may indicate that one of the primary mechanisms by which P. vivax evades host immunity is through DARC indirectly down-regulating humoral responses against erythrocytic invasion and development. 相似文献998.
In this study, the relationship between the concentration of extra-heavy crude petroleum in a clayey material and the toxicity, field capacity, temperature, and growth of a tropical forage grass (Brachiara humidicola) was determined empirically. For this type of petroleum the acute toxicity (Microtox®) was slight (CE50 = 63200 - 76400 mg/kg) even at high hydrocarbon concentrations (29279 mg/kg). Nonetheless, serious impacts were encountered in terms of an increase in soil temperature (+ 1.3 °C), reduction in field capacity (-10.7%) and reduction in aerial biomass (-97%). The relationship between hydrocarbon concentration and biomass resulted in a typical dose-response curve (r = 0.99), where a concentration of 2626 mg/kg of hydrocarbons corresponds to a maintenance of 90% biomass. Furthermore, during the duration of this study (one year) the biodegradation was proportional to the pasture biomass production (r = 0.997) indicating a synergistic relationship between the petroleum biodegrading microorganisms in the rhizosphere and the pasture. 相似文献
999.
1000.
Nup42 and IP6 coordinate Gle1 stimulation of Dbp5/DDX19B for mRNA export in yeast and human cells 下载免费PDF全文
Rebecca L. Adams Aaron C. Mason Laura Glass Aditi Susan R. Wente 《Traffic (Copenhagen, Denmark)》2017,18(12):776-790
The mRNA lifecycle is driven through spatiotemporal changes in the protein composition of mRNA particles (mRNPs) that are triggered by RNA‐dependent DEAD‐box protein (Dbp) ATPases. As mRNPs exit the nuclear pore complex (NPC) in Saccharomyces cerevisiae, this remodeling occurs through activation of Dbp5 by inositol hexakisphosphate (IP6)‐bound Gle1. At the NPC, Gle1 also binds Nup42, but Nup42's molecular function is unclear. Here we employ the power of structure‐function analysis in S. cerevisiae and human (h) cells, and find that the high‐affinity Nup42‐Gle1 interaction is integral to Dbp5 (hDDX19B) activation and efficient mRNA export. The Nup42 carboxy‐terminal domain (CTD) binds Gle1/hGle1B at an interface distinct from the Gle1‐Dbp5/hDDX19B interaction site. A nup42‐CTD/gle1‐CTD/Dbp5 trimeric complex forms in the presence of IP6. Deletion of NUP42 abrogates Gle1‐Dbp5 interaction, and disruption of the Nup42 or IP6 binding interfaces on Gle1/hGle1B leads to defective mRNA export in S. cerevisiae and human cells. In vitro, Nup42‐CTD and IP6 stimulate Gle1/hGle1B activation of Dbp5 and DDX19B recombinant proteins in similar, nonadditive manners, demonstrating complete functional conservation between humans and S. cerevisiae. Together, a highly conserved mechanism governs spatial coordination of mRNP remodeling during export. This has implications for understanding human disease mutations that perturb the Nup42‐hGle1B interaction. 相似文献