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991.
Isaac G. Sakala Geeta Chaudhri Anthony A. Scalzo Preethi Eldi Timothy P. Newsome Robert M. Buller Gunasegaran Karupiah 《PLoS pathogens》2015,11(12)
Orthopoxviruses (OPV), including variola, vaccinia, monkeypox, cowpox and ectromelia viruses cause acute infections in their hosts. With the exception of variola virus (VARV), the etiological agent of smallpox, other OPV have been reported to persist in a variety of animal species following natural or experimental infection. Despite the implications and significance for the ecology and epidemiology of diseases these viruses cause, those reports have never been thoroughly investigated. We used the mouse pathogen ectromelia virus (ECTV), the agent of mousepox and a close relative of VARV to investigate virus persistence in inbred mice. We provide evidence that ECTV causes a persistent infection in some susceptible strains of mice in which low levels of virus genomes were detected in various tissues late in infection. The bone marrow (BM) and blood appeared to be key sites of persistence. Contemporaneous with virus persistence, antiviral CD8 T cell responses were demonstrable over the entire 25-week study period, with a change in the immunodominance hierarchy evident during the first 3 weeks. Some virus-encoded host response modifiers were found to modulate virus persistence whereas host genes encoded by the NKC and MHC class I reduced the potential for persistence. When susceptible strains of mice that had apparently recovered from infection were subjected to sustained immunosuppression with cyclophosphamide (CTX), animals succumbed to mousepox with high titers of infectious virus in various organs. CTX treated index mice transmitted virus to, and caused disease in, co-housed naïve mice. The most surprising but significant finding was that immunosuppression of disease-resistant C57BL/6 mice several weeks after recovery from primary infection generated high titers of virus in multiple tissues. Resistant mice showed no evidence of a persistent infection. This is the strongest evidence that ECTV can persist in inbred mice, regardless of their resistance status. 相似文献
992.
Bao KK Wang H Miller JK Erie DA Skalka AM Wong I 《The Journal of biological chemistry》2003,278(2):1323-1327
Retroviral integrase, one of only three enzymes encoded by the virus, catalyzes the essential step of inserting a DNA copy of the viral genome into the host during infection. Using the avian sarcoma virus integrase, we demonstrate that the enzyme functions as a tetramer. In presteady-state active site titrations, four integrase protomers were required for a single catalytic turnover. Volumetric determination of integrase-DNA complexes imaged by atomic force microscopy during the initial turnover additionally revealed substrate-induced assembly of a tetramer. These results suggest that tetramer formation may be a requisite step during catalysis with ramifications for antiviral design strategies targeting the structurally homologous human immunodeficiency virus, type 1 (HIV-1) integrase. 相似文献
993.
Antiviral inhibition of the HIV-1 capsid protein 总被引:9,自引:0,他引:9
Tang C Loeliger E Kinde I Kyere S Mayo K Barklis E Sun Y Huang M Summers MF 《Journal of molecular biology》2003,327(5):1013-1020
994.
E. Dirlewanger P. G. Isaac S. Ranade M. Belajouza R. Cousin D. de Vienne 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1994,88(1):17-27
An F2 population of pea (Pisum sativum L.) consisting of 174 plants was analysed by restriction fragment length polymorphism (RFLP) and random amplified polymorphic DNA (RAPD) techniques. Ascochyta pisi race C resistance, plant height, flowering earliness and number of nodes were measured in order to map the genes responsible for their variation. We have constructed a partial linkage map including 3 morphological character genes, 4 disease resistance genes, 56 RFLP loci, 4 microsatellite loci and 2 RAPD loci. Molecular markers linked to each resistance gene were found: Fusarium wilt (6 cM from Fw), powdery mildew (11 cM from er) and pea common Mosaic virus (15 cM from mo). QTLs (quantitative traits loci) for Ascochyta pisi race C resistance were mapped, with most of the variation explained by only three chromosomal regions. The QTL with the largest effect, on chromosome 4, was also mapped using a qualitative, Mendelian approach. Another QTL displayed a transgressive segregation, i.e. the parental line that was susceptible to Ascochyta blight had a resistance allele at this QTL. Analysis of correlations between developmental traits in terms of QTL effects and positions suggested a common genetic control of the number of nodes and earliness, and a loose relationship between these traits and height. 相似文献
995.
Kabel MA Yeoman CJ Han Y Dodd D Abbas CA de Bont JA Morrison M Cann IK Mackie RI 《Applied and environmental microbiology》2011,77(16):5671-5681
996.
Gemma Flores-Mateo Roberto Elosua Teresa Rodriguez-Blanco Josep Basora-Gallisà Mònica Bulló Jordi Salas-Salvadó Miguel ángel Martínez-González Ramon Estruch Dolores Corella Montserrat Fitó Miquel Fiol Fernando Arós Enrique Gómez-Gracia Isaac Subirana José Lapetra Valentina Ruiz-Gutiérrez Guillermo T. Sáez Maria-Isabel Covas for the PREDIMED Study Investigators 《PloS one》2014,9(9)
Background
Studies of associations between plasma GSH-Px activity and cardiovascular risk factors have been done in humans, and contradictory results have been reported. The aim of our study was to assess the association between the scavenger antioxidant enzyme glutathione peroxidase (GSH-Px) activity in plasma and the presence of novel and classical cardiovascular risk factors in elderly patients.Methods
We performed a cross-sectional study with baseline data from a subsample of the PREDIMED (PREvención con DIeta MEDiterránea) study in Spain. Participants were 1,060 asymptomatic subjects at high risk for cardiovascular disease (CVD), aged 55 to 80, selected from 8 primary health care centers (PHCCs). We assessed classical CVD risk factors, plasma oxidized low-density lipoproteins (ox-LDL), and glutathione peroxidase (GSH-Px) using multilevel statistical procedures.Results
Mean GSH-Px value was 612 U/L (SE: 12 U/L), with variation between PHCCs ranging from 549 to 674 U/L (Variance = 1013.5; P<0.001). Between-participants variability within a PHCC accounted for 89% of the total variation. Both glucose and oxidized LDL were positively associated with GSH-Px activity after adjustment for possible confounder variables (P = 0.03 and P = 0.01, respectively).Conclusion
In a population at high cardiovascular risk, a positive linear association was observed between plasma GSH-Px activity and both glucose and ox-LDL levels. The high GSH-Px activity observed when an oxidative stress situation occurred, such as hyperglycemia and lipid oxidative damage, could be interpreted as a healthy defensive response against oxidative injury in our cardiovascular risk population. 相似文献997.
998.
999.
1000.
A study was made of the effects of foliar spray of bacitracin, chloramphenicol and gibberellic acid on the rhizosphere microflora
of pea seedlings (Pisum sativum L.) infected withVerticillium dahliae. The antibiotics increased fungus and actinomycete counts and reduced the bacterial populations in the rhizosphere. Gibberellic
acid at 10 ppm concentration reduced all three groups of microorganisms while at 100 ppm fungi and actinomycetes increased
slightly. Invariably the rhizosphere effect was as follows: bacteria > fungi > actinomycetes. Foliar sprays also affected
the percentage occurrence of particular genera of fungi in the rhizosphere; for example,Trichoderma spp. were stimulated by all the treatments, the maximum being with 10 ppm gibberellic acid, even though the total fungus
count was reduced. The disease severity was markedly reduced by foliar sprays. 相似文献