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111.
Kumar T Liestøl K Maehlen J Hiorth A Jettestuen E Lind H Brorson SH 《Human biology; an international record of research》2002,74(1):137-142
This study examines the distribution of apolipoprotein E (APOE) alleles in a population of healthy male and female Norwegians (n = 798) below the age of 40. The -491A/T polymorphism of the promoter region of the APOE gene was also examined. A seminested polymerase chain reaction was applied in the genotyping. The results showed that the E3 allele had the highest frequency (0.744), followed by E4 (0.198) and E2 (0.058). The APOE frequencies found in this study differ significantly from those obtained in earlier Norwegian APOE phenotypings. The allele frequencies in the -491 site of the promoter region were 0.845 for the A allele and 0.155 for the T allele. The genotype frequency was highest for AA (0.707), followed by AT (0.277) and TT (0.016). Moreover, the A allele was in linkage disequilibrium to E4. 相似文献
112.
Avian disease at the Salton Sea 总被引:3,自引:3,他引:0
Milton Friend 《Hydrobiologia》2002,473(1-3):293-306
A review of existing records and the scientific literature was conducted for occurrences of avian diseases affecting free-ranging avifauna within the Salton Sea ecosystem. The period for evaluation was 1907 through 1999. Records of the U.S. Department of Agriculture, Bureau of Biological Survey and the scientific literature were the data sources for the period of 1907–1939. The narrative reports of the U.S. Fish and Wildlife Service's Sonny Bono National Wildlife Refuge Complex and the epizootic database of the U.S. Geological Survey's National Wildlife Health Center were the primary data sources for the remainder of the evaluation. The pattern of avian disease at the Salton Sea has changed greatly over time. Relative to past decades, there was a greater frequency of major outbreaks of avian disease at the Salton Sea during the 1990s than in previous decades, a greater variety of disease agents causing epizootics, and apparent chronic increases in the attrition of birds from disease. Avian mortality was high for about a decade beginning during the mid-1920s, diminished substantially by the 1940s and was at low to moderate levels until the 1990s when it reached the highest levels reported. Avian botulism (Clostridium botulinum type C) was the only major cause of avian disease until 1979 when the first major epizootic of avian cholera (Pasteurella multocidia) was documented. Waterfowl and shorebirds were the primary species affected by avian botulism. A broader spectrum of species have been killed by avian cholera but waterfowl have suffered the greatest losses. Avian cholera reappeared in 1983 and has joined avian botulism as a recurring cause of avian mortality. In 1989, avian salmonellosis (Salmonella typhimurium) was first diagnosed as a major cause of avian disease within the Salton Sea ecosystem and has since reappeared several times, primarily among cattle egrets (Bubulcus ibis). The largest loss from a single epizootic occurred in 1992, when an estimated 155000 birds, primarily eared grebes (Podiceps nigricollis), died from an undiagnosed cause. Reoccurrences of that unknown malady have continued to kill substantial numbers of eared grebes throughout the 1990s. The first major epizootic of type C avian botulism in fish-eating birds occurred in 1996 and killed large numbers of pelicans (Pelecanus occidentalis & P. erythrorhynchos). Avian botulism has remained as a major annual cause of disease in pelicans. In contrast, the chronic on-Sea occurrence of avian botulism in waterfowl and shorebirds of previous decades was seldom seen during the 1990s. Newcastle disease became the first viral disease to cause major bird losses at the Salton Sea when it appeared in the Mullet Island cormorant (Phalacrocorax auritus) breeding colony during 1997 and again during 1998. 相似文献
113.
Identification of GtgE,a novel virulence factor encoded on the Gifsy-2 bacteriophage of Salmonella enterica serovar Typhimurium
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Ho TD Figueroa-Bossi N Wang M Uzzau S Bossi L Slauch JM 《Journal of bacteriology》2002,184(19):5234-5239
The Gifsy-2 temperate bacteriophage of Salmonella enterica serovar Typhimurium contributes significantly to the pathogenicity of strains that carry it as a prophage. Previous studies have shown that Gifsy-2 encodes SodCI, a periplasmic Cu/Zn superoxide dismutase, and at least one additional virulence factor. Gifsy-2 encodes a Salmonella pathogenicity island 2 type III secreted effector protein. Sequence analysis of the Gifsy-2 genome also identifies several open reading frames with homology to those of known virulence genes. However, we found that null mutations in these genes did not individually have a significant effect on the ability of S. enterica serovar Typhimurium to establish a systemic infection in mice. Using deletion analysis, we have identified a gene, gtgE, which is necessary for the full virulence of S. enterica serovar Typhimurium Gifsy-2 lysogens. Together, GtgE and SodCI account for the contribution of Gifsy-2 to S. enterica serovar Typhimurium virulence in the murine model. 相似文献
114.
Human immunodeficiency virus type 1-hepatitis C virus coinfection: intraindividual comparison of cellular immune responses against two persistent viruses 总被引:7,自引:0,他引:7
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Lauer GM Nguyen TN Day CL Robbins GK Flynn T McGowan K Rosenberg ES Lucas M Klenerman P Chung RT Walker BD 《Journal of virology》2002,76(6):2817-2826
Both human immunodeficiency virus type 1 (HIV-1) and hepatitis C virus (HCV) lead to chronic infection in a high percentage of persons, and an expanding epidemic of HIV-1-HCV coinfection has recently been identified. These individuals provide an opportunity for simultaneous assessment of immune responses to two viral infections associated with chronic plasma viremia. In this study we analyzed the breadth and magnitude of the CD8(+)- and CD4(+)-T-lymphocyte responses in 22 individuals infected with both HIV-1 and HCV. A CD8(+)-T-lymphocyte response against HIV-1 was readily detected in all subjects over a broad range of viral loads. In marked contrast, HCV-specific CD8(+)-T-lymphocyte responses were rarely detected, despite viral loads in plasma that were on average 1,000-fold higher. The few HCV-specific responses that were observed were relatively weak and limited in breadth. CD4-proliferative responses against HIV-1 were detected in about half of the coinfected subjects tested, but no proliferative response against any HCV protein was found in these coinfected persons. These data demonstrate a major discordance in immune responses to two persistent RNA viruses. In addition, they show a consistent and profound impairment in cellular immune responses to HCV compared to HIV-1 in HIV-1-HCV-coinfected persons. 相似文献
115.
Sex expression in the dioecious plant white campion (Silene latifolia Poiret subsp. alba) appears to be insensitive to exogenous applications of auxins, cytokinins, gibberellic acid, and ethylene; however, silver thiosulfate (Ag(2)S(2)O(3)), an ethylene inhibitor, enhanced stamen development in female white campion. In wild-type females, stamen development is arrested before the microspore mother cells are formed. In contrast, stamens of Ag(2)S(2)O(3)-treated females completed meiosis and produced microspores. Stamen development for these females was incomplete, however, and pollen did not mature. Ag(2)S(2)O(3) stimulated stamen development to the same extent in asexual white campion mutants that retained a Y chromosome but had lost Y-linked genes needed for early stages of stamen development. Although Ag(2)S(2)O(3) can inhibit ethylene signaling, the enhancement of stamen development in female white campion cannot be explained as a loss of ethylene response because no other ethylene inhibitor tested (1-methylcyclopropene, trans-cyclooctene, aminoethoxyvinylglycine, and cobalt chloride) caused stamens to develop in female plants. In addition, application of other metal ions could not enhance stamen development. Therefore, the effect we observed on female white campion was specifically caused by silver ions but not by their action on ethylene signaling. 相似文献
116.
A genomewide linkage scan for quantitative-trait loci for obesity phenotypes 总被引:16,自引:0,他引:16
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Deng HW Deng H Liu YJ Liu YZ Xu FH Shen H Conway T Li JL Huang QY Davies KM Recker RR 《American journal of human genetics》2002,70(5):1138-1151
Obesity is an increasingly serious health problem in the world. Body mass index (BMI), percentage fat mass, and body fat mass are important indices of obesity. For a sample of pedigrees that contains >10,000 relative pairs (including 1,249 sib pairs) that are useful for linkage analyses, we performed a whole-genome linkage scan, using 380 microsatellite markers to identify genomic regions that may contain quantitative-trait loci (QTLs) for obesity. Each pedigree was ascertained through a proband who has extremely low bone mass, which translates into a low BMI. A major QTL for BMI was identified on 2q14 near the marker D2S347 with a LOD score of 4.04 in two-point analysis and a maximum LOD score (MLS) of 4.44 in multipoint analysis. The genomic region near 2q14 also achieved an MLS >2.0 for percentage of fat mass and body fat mass. For the putative QTL on 2q14, as much as 28.2% of BMI variation (after adjustment for age and sex) may be attributable to this locus. In addition, several other genomic regions that may contain obesity-related QTLs are suggested. For example, 1p36 near the marker D1S468 may contain a QTL for BMI variation, with a LOD score of 2.75 in two-point analysis and an MLS of 2.09 in multipoint analysis. The genomic regions identified in this and earlier reports are compared for further exploration in extension studies that use larger samples and/or denser markers for confirmation and fine-mapping studies, to eventually identify major functional genes involved in obesity. 相似文献
117.
The Gradiflow trade mark, a preparative electrophoresis instrument capable of separating proteins on the basis of their size or charge, was used to separate whole cell lysates, prepared from bakers yeast (Saccharomyces cerevisiae) and Chinese snow pea seeds (Pisum sativum macrocarpon), into protein fractions of different pH regions. Both broad and narrow range (with a difference of approximately 1 pH unit) pH fractions were obtained. Analysis of the protein fractions by isoelectric focusing gels and two-dimensional (2-D) polyacrylamide gel electrophoresis indicated minimal overlap between the pH fractions. Further, when the prefractionated acidic samples were analyzed on pH 4-7 immobilized pH gradient 2-D gels, improved resolution of the proteins within the chosen pH region was achieved compared to the unfractionated samples. This study demonstrates that the Gradiflow could be used as a preparative electrophoresis tool for the isolation of proteins into distinct pH fractions. 相似文献
118.
Michie S Collins V Halliday J Marteau TM;FAP Collaborative Research Group 《Genetic testing》2002,6(4):307-311
This study was undertaken to determine the extent to which the reported likelihood of attending future bowel screening following negative genetic testing results for familial adenomatous polyposis (FAP) varies between the type of health professional providing care and the country of testing. The study subjects were 103 unaffected adults at risk for FAP who received negative results following predictive DNA testing. Our study indicates that the reported likelihood of attending bowel screening was higher in those given results by nongenetics physicians, rather than by genetics professionals; the reported likelihood of attending bowel screening under these circumstances was also higher in the UK than in Australia. Both of these results were affected by the perceived chances of developing FAP, and, in the case of the country of testing, by the perceived accuracy of the genetic test result and the perceived seriousness of the disease. How and what health professionals communicate with patients about genetic testing may explain the differences between type of health professional and country of testing and attitudes toward bowel screening. If this is the case, training in communication may change patients' perceptions and, in turn, their behavioral intentions and actions following a negative test result. 相似文献
119.
Sessions A Burke E Presting G Aux G McElver J Patton D Dietrich B Ho P Bacwaden J Ko C Clarke JD Cotton D Bullis D Snell J Miguel T Hutchison D Kimmerly B Mitzel T Katagiri F Glazebrook J Law M Goff SA 《The Plant cell》2002,14(12):2985-2994
A collection of Arabidopsis lines with T-DNA insertions in known sites was generated to increase the efficiency of functional genomics. A high-throughput modified thermal asymmetric interlaced (TAIL)-PCR protocol was developed and used to amplify DNA fragments flanking the T-DNA left borders from approximately 100000 transformed lines. A total of 85108 TAIL-PCR products from 52964 T-DNA lines were sequenced and compared with the Arabidopsis genome to determine the positions of T-DNAs in each line. Predicted T-DNA insertion sites, when mapped, showed a bias against predicted coding sequences. Predicted insertion mutations in genes of interest can be identified using Arabidopsis Gene Index name searches or by BLAST (Basic Local Alignment Search Tool) search. Insertions can be confirmed by simple PCR assays on individual lines. Predicted insertions were confirmed in 257 of 340 lines tested (76%). This resource has been named SAIL (Syngenta Arabidopsis Insertion Library) and is available to the scientific community at www.tmri.org. 相似文献
120.
Identification,analysis, and utilization of conserved ortholog set markers for comparative genomics in higher plants 总被引:26,自引:0,他引:26
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We have screened a large tomato EST database against the Arabidopsis genomic sequence and report here the identification of a set of 1025 genes (referred to as a conserved ortholog set, or COS markers) that are single or low copy in both genomes (as determined by computational screens and DNA gel blot hybridization) and that have remained relatively stable in sequence since the early radiation of dicotyledonous plants. These genes were annotated, and a large portion could be assigned to putative functional categories associated with basic metabolic processes, such as energy-generating processes and the biosynthesis and degradation of cellular building blocks. We further demonstrate, through computational screens (e.g., against a Medicago truncatula database) and direct hybridization on genomic DNA of diverse plant species, that these COS markers also are conserved in the genomes of other plant families. Finally, we show that this gene set can be used for comparative mapping studies between highly divergent genomes such as those of tomato and Arabidopsis. This set of COS markers, identified computationally and experimentally, may further studies on comparative genomes and phylogenetics and elucidate the nature of genes conserved throughout plant evolution. 相似文献