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81.
Panda S Kumar MS Lokabiraman S Jayashree K Satagopan MC Solomon S Rao UA Rangaiyan G Flessenkaemper S Grosskurth H Gupte MD 《Journal of acquired immune deficiency syndromes (1999)》2005,39(1):9-15
OBJECTIVES: Determining HIV prevalence in injection drug users (IDUs) and their regular sex partners in Chennai, India. METHODS: A total of 226 IDUs and their regular sex partners were enrolled during April-July 2003. After informed consent was obtained, a semistructured questionnaire was administered and serum was tested for HIV antibody. RESULTS: The HIV seroprevalence was 30% (68/226) in IDUs and 5% in their regular sex partners (11/226). While in 25% of couples only the male partner was HIV positive, 5% of the couples were concordant for HIV infection and 70% were HIV negative. Fifty-seven percent of the HIV-positive IDUs and 45% of the HIV-infected women thought that they had "no chance" or "very little chance" of getting HIV, reflecting low HIV risk perception. More than 20% IDUs reported borrowing or lending of injection equipment. In univariate analyses "sex" and "condom use" with sex workers had no bearing but "more than twice a day injecting frequency," "history of incarceration," "tattoos," "recruitment from northern part of the city," and ever-injecting drugs in drug-selling places had significant association with HIV infection in IDUs. In an adjusted model, the odds of HIV infection were 2 times higher among IDUs who had ever injected drugs in drug-selling places and 6 times higher in those who were recruited from the northern part of central Chennai. CONCLUSION: Reducing sharing of injection equipment and unsafe tattooing through targeted and environmental interventions, increasing HIV risk perception, and promoting safer sex practices among IDUs and their sex partners are urgent program needs. 相似文献
82.
Characterization of virus-like particles assembled in a recombinant baculovirus system expressing the capsid protein of a fish nodavirus 总被引:8,自引:0,他引:8
Lin CS Lu MW Tang L Liu W Chao CB Lin CJ Krishna NK Johnson JE Schneemann A 《Virology》2001,285(1):50-58
Infectious bursal disease virus (IBDV) causes severe immunodeficiency in young chickens by destroying the precursors of antibody-producing B cells in the bursa of Fabricius. It has been shown that IBDV infection induces apoptosis in chicken embryo and tissue culture cells. We previously reported that an IBDV mutant lacking the expression of 17-kDa nonstructural (NS) protein exhibited decreased apoptotic effects in cell culture as compared to the parental IBDV, suggesting that the NS protein may be involved in induction of apoptosis. Here, we report that the NS protein of IBDV alone is capable of inducing apoptosis in cell culture. Transfection of chicken B-lymphocyte cell line (RP9) and chicken embryo fibroblast cells with a plasmid DNA, containing the NS protein gene under the control of the immediate-early promoter-enhancer region of human cytomegalovirus, induced programmed cell death in both cell lines. Apoptosis changes, such as chromatin condensation, DNA fragmentation, and the appearance of apoptotic nuclear bodies, were observed in cell cultures 48-h posttransfection. As reported earlier, the mutant IBDV grew to lower titers with slower replication kinetics and lower cytopathogenicity when compared to that of the parental virus. Here, we demonstrate that the mutant virus is closely associated with cells and its yield from the supernatant was approximately 30-fold lower than the wild-type due to increased cell association, indicating a deficiency in lysis of virus-infected cells. Taken together, our results indicate that the NS protein of IBDV is highly cytotoxic, which brings about the release of the viral progeny from cells, and thus play an important role in viral pathogenesis. 相似文献
83.
Anand Shah Danny O Jacobs Henrique Martins Matthew Harker Andreia Menezes Mariana McCready Ricardo Pietrobon 《BMC medical informatics and decision making》2006,6(1):34
Background
The Internet has been increasingly utilized in biomedical research. From online searching for literature to data sharing, the Internet has emerged as a primary means of research for many physicians and scientists. As a result, Web-based surveys have been employed as an alternative to traditional, paper-based surveys. We describe DADOS-Survey, an open-source Web-survey application developed at our institution that, to the best of our knowledge, is the first to be compliant with the Checklist for Reporting Results of Internet E-Surveys (CHERRIES). DADOS-Survey was designed with usability as a priority, allowing investigators to design and execute their own studies with minimal technical difficulties in doing so. 相似文献84.
Friend virus was used to infect and transform Fv-2rr erythroprogenitor cells in vivo. The RB (Fv-2rr) cell line was characteristic of Friend virus-induced cell lines in Fv-2ss mice, i.e., it produced infectious Friend virus and synthesized hemoglogin. The RB (Fv-2rr) cell line expressed the envelope protein of the spleen focus-forming virus (gp52) and a novel, related envelope protein (gp48). The results demonstrate that Fv-2rr erythroprogenitor cells can be infected and transformed in vivo. 相似文献
85.
Comparative recombination rates in the rat, mouse, and human genomes 总被引:18,自引:3,他引:18
Jensen-Seaman MI Furey TS Payseur BA Lu Y Roskin KM Chen CF Thomas MA Haussler D Jacob HJ 《Genome research》2004,14(4):528-538
Levels of recombination vary among species, among chromosomes within species, and among regions within chromosomes in mammals. This heterogeneity may affect levels of diversity, efficiency of selection, and genome composition, as well as have practical consequences for the genetic mapping of traits. We compared the genetic maps to the genome sequence assemblies of rat, mouse, and human to estimate local recombination rates across these genomes. Humans have greater overall levels of recombination, as well as greater variance. In rat and mouse, the size of the chromosome and proximity to telomere have less effect on local recombination rate than in human. At the chromosome level, rat and mouse X chromosomes have the lowest recombination rates, whereas human chromosome X does not show the same pattern. In all species, local recombination rate is significantly correlated with several sequence variables, including GC%, CpG density, repetitive elements, and the neutral mutation rate, with some pronounced differences between species. Recombination rate in one species is not strongly correlated with the rate in another, when comparing homologous syntenic blocks of the genome. This comparative approach provides additional insight into the causes and consequences of genomic heterogeneity in recombination. 相似文献
86.
The unusual occurrence of very large cysticerci presenting as tumour-like lesions prompted this search of the pathology records of a south Indian hospital, to find similar cases. The maximum diameter of 187 consecutively diagnosed extraneural cysticerci, was recorded and those cases exceeding the mean by two standard deviations reviewed. Six biopsies showing cysticerci with a maximum diameter ranging from 4 to 11 cm, were identified, and hospital records and all pathological material available, were reexamined. The clinical differential diagnosis included benign and malignant tumours, hydatid cyst and haematoma. All the cysts were confirmed to be cysticerci, but species diagnosis was not possible by examining archival material. In an appropriate geographical setting, large cysticerci should form part of the differential diagnosis of cystic tumour-like lesions. An attemp can then be made, while the specimen is still fresh, to identify the species. 相似文献
87.
Distribution of galanin immunoreactivity in the central nervous system and the responses of galanin-containing neuronal pathways to injury 总被引:18,自引:0,他引:18
J L Ch'ng N D Christofides P Anand S J Gibson Y S Allen H C Su K Tatemoto J F Morrison J M Polak S R Bloom 《Neuroscience》1985,16(2):343-354
Radioimmunoassay and immunocytochemistry were used to study the distribution of galanin, a novel 29 amino acid porcine intestinal peptide, in the central nervous system of the rat and pig. The pattern of distribution was similar in the two species, with the highest concentrations of galanin-like immunoreactivity found in the neurohypophysis, hypothalamus and sacral spinal cord. Immunocytochemical studies of these regions localized galanin-like immunoreactivity to cell bodies in the paraventricular and supraoptic nuclei of the hypothalamus, to fibres in the pars nervosa and to numerous cell bodies and fibres in the dorsal horn of the spinal cord. On both gel and high pressure liquid chromatography, galanin-like immunoreactivity in rat and pig nervous tissue eluted as a single peak in a position similar to purified procine intestinal galanin standard. Surgical and pharmacological manipulations in the rat suggest the presence of galanin in afferent fibres. An increase of galanin-like immunoreactivity was observed in the sacral spinal cord of the rat following thoracic spinal cord transection. Thus galanin-like immunoreactivity in the brain is mainly localized in the hypothalamopituitary region. The decrease of galanin-like immunoreactivity in the dorsal horn of the spinal cord, following dorsal rhizotomy and pre-treatment of rats with capsaicin, indicates that many of the fibres, which are of small diameter, may well be derived from spinal sensory neurones. 相似文献
88.
Ricardo Pietrobon Anand Shah Paul Kuo Matthew Harker Mariana McCready Christeen Butler Henrique Martins CT Moorman Danny O Jacobs 《BMC medical informatics and decision making》2006,6(1):32-11
Background
Although regulatory compliance in academic research is enforced by law to ensure high quality and safety to participants, its implementation is frequently hindered by cost and logistical barriers. In order to decrease these barriers, we have developed a Web-based application, Duke Surgery Research Central (DSRC), to monitor and streamline the regulatory research process. 相似文献89.
Chloroform toxicity in mice: correlation of renal and hepatic necrosis with covalent binding of metabolites to tissue macromolecules 总被引:4,自引:0,他引:4
Chloroform (CHCl3) treatment caused centrolobular hepatic necrosis in mice of both sexes whereas renal necrosis was observed only in male mice. Following administration of 14CHCl3 to mice, substantial amounts (about 3 mmole/g) of radiolabeled material were covalently bound to proteins in the liver and kidney. The amount of convalent binding paralleled the extent of renal and hepatic necrosis both in normal animals and in male mice pretreated with either phenobarbital or piperonyl butoxide, agents which induce or block, respectively, microsomal drug metabolizing enzymes. These results suggest that the covalent binding is due to a metabolite of CHCl3. Evidence that the covalent binding is causally related to the tissue necrosis was obtained from autoradiograms showing that the radioactivity is located mainly in the necrotic lesions. 相似文献
90.
An experimental model of carditis has been produced in the rhesus monkey by giving 12 weekly injections of a streptococcal membrane antigen. There was histological evidence of focal myocarditis, subendocardial infiltration with lymphomononuclear cells and in one animal myocardial granuloma formation. No valvular lesions were seen. Humoral immune responses monitored throughout the experiment showed that anti-heart antibodies appeared in circulation after the 2nd injection, attained maximal titres by the 6th injection, and thereafter the titres declined. The anti-membrane antibodies appeared slightly later and these titres kept rising till sacrifice. By the 6th injection there was evidence of complement consumption and appearance of circulating immune complexes. It is concluded that these immunological responses might have a role to play in the pathogenesis of carditis. 相似文献