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81.
Background. Studies on eradication therapy in developing countries have shown a success rate of 70–85%, which is suboptimal. Duration of therapy may be an important factor dictating eradication success in such regions. Aim. The study was undertaken to evaluate the effect of increasing the treatment period on eradication of Helicobacter pylori in duodenal ulcer disease. Methods. A randomized trial was carried out in which 64 consecutive H. pylori‐infected patients with duodenal ulcer disease were enrolled. The patients were randomized to one of the three trial arms. Therapy consisted of lansoprazole 30 mg twice a day (b.i.d.), amoxycillin 1 g b.i.d. and tinidazole 500 mg b.i.d. The treatment period was 1 week in group I, 2 weeks in group II and 3 weeks in group III. At inclusion, patients underwent endoscopy and the presence of H. pylori was documented by a positive urease test and C14 urea breath test. Four weeks after completion of eradication therapy, the patients were subjected to repeat endoscopy to assess ulcer healing and tests for H. pylori infection. Results. Sixty‐four patients (55 male and nine female; mean age 35.5 years) were enrolled in each group. The H. pylori eradication rate for group I (1 week of therapy) was 47.6%, that for group II (2 weeks of therapy) was 80%, and that for group III (3 weeks of therapy) was 91.3% (p = .003). The ulcer healing rates were 71.4, 80 and 95.6% in groups I, II and III, respectively (p = .09). Conclusion. The 3‐week regimen significantly improved the eradication rate as compared with the 1‐week regime. Increasing the duration of therapy significantly improved the chances of eradication of H. pylori in duodenal ulcer disease. 相似文献
82.
Severe CD4+ T-cell depletion in gut lymphoid tissue during primary human immunodeficiency virus type 1 infection and substantial delay in restoration following highly active antiretroviral therapy 总被引:1,自引:0,他引:1 下载免费PDF全文
Guadalupe M Reay E Sankaran S Prindiville T Flamm J McNeil A Dandekar S 《Journal of virology》2003,77(21):11708-11717
Gut-associated lymphoid tissue (GALT) harbors the majority of T lymphocytes in the body and is an important target for human immunodeficiency virus type 1 (HIV-1). We analyzed longitudinal jejunal biopsy samples from HIV-1-infected patients, during both primary and chronic stages of HIV-1 infection, prior to and following the initiation of highly active antiretroviral therapy (HAART) to determine the onset of CD4(+) T-cell depletion and the effect of HAART on the restoration of CD4(+) T cells in GALT. Severe depletion of intestinal CD4(+) T cells occurred during primary HIV-1 infection. Our results showed that the restoration of intestinal CD4(+) T cells following HAART in chronically HIV-1-infected patients was substantially delayed and incomplete. In contrast, initiation of HAART during early stages of infection resulted in near-complete restoration of intestinal CD4(+) T cells, despite the delay in comparison to peripheral blood CD4(+) T-cell recovery. DNA microarray analysis of gene expression profiles and flow-cytometric analysis of lymphocyte homing and cell proliferation markers demonstrated that cell trafficking to GALT and not local proliferation contributed to CD4(+) T-cell restoration. Evaluation of jejunal biopsy samples from long-term HIV-1-infected nonprogressors showed maintenance of normal CD4(+) T-cell levels in both GALT and peripheral blood. Our results demonstrate that near-complete restoration of mucosal immune system can be achieved by initiating HAART early in HIV-1 infection. Monitoring of the restoration and/or maintenance of CD4(+) T cells in GALT provides a more accurate assessment of the efficacy of antiviral host immune responses as well as HAART. 相似文献
83.
Davis FJ Gupta M Camoretti-Mercado B Schwartz RJ Gupta MP 《The Journal of biological chemistry》2003,278(22):20047-20058
84.
85.
Removal of some commonly used protecting groups in peptide synthesis by catalytic transfer hydrogenation employing hydrazinium monoformate and 10%Pd on carbon is described. This method is equally competitive with other methods in deblocking most of the commonly used protecting groups in peptide synthesis. tert-Butyl derived and base labile protecting groups were completely stable under these conditions. This is more effective than hydrazine or formic acid. 相似文献
86.
Replication and compartmentalization of HIV-1 in kidney epithelium of patients with HIV-associated nephropathy 总被引:11,自引:0,他引:11
Marras D Bruggeman LA Gao F Tanji N Mansukhani MM Cara A Ross MD Gusella GL Benson G D'Agati VD Hahn BH Klotman ME Klotman PE 《Nature medicine》2002,8(5):522-526
HIV-associated nephropathy is a clinicopathologic entity that includes proteinuria, focal segmental glomerulosclerosis often of the collapsing variant, and microcystic tubulointerstitial disease. Increasing evidence supports a role for HIV-1 infection of renal epithelium in the pathogenesis of HIV-associated nephropathy. Using in situ hybridization, we previously demonstrated HIV-1 gag and nef mRNA in renal epithelial cells of patients with HIV-associated nephropathy. Here, to investigate whether renal epithelial cells were productively infected by HIV-1, we examined renal tissue for the presence of HIV-1 DNA and mRNA by in situ hybridization and PCR, and we molecularly characterized the HIV-1 quasispecies in the renal compartment. Infected renal epithelial cells were removed by laser-capture microdissection from biopsies of two patients, DNA was extracted, and HIV-1 V3-loop or gp120-envelope sequences were amplified from individually dissected cells by nested PCR. Phylogenetic analysis of kidney-derived sequences as well as corresponding sequences from peripheral blood mononuclear cells of the same patients revealed evidence of tissue-specific viral evolution. In phylogenetic trees constructed from V3 and gp120 sequences, kidney-derived sequences formed tissue-specific subclusters within the radiation of blood mononuclear cell-derived viral sequences from both patients. These data, along with the detection of HIV-1-specific proviral DNA and mRNA in tubular epithelium cells, argue strongly for localized replication of HIV-1 in the kidney and the existence of a renal viral reservoir. 相似文献
87.
88.
Subramanian M Chintalwar GJ Chattopadhyay S 《Indian journal of biochemistry & biophysics》2003,40(1):22-26
Radioprotective activity of a polysaccharide preparation from the Indian medicinal plant. Tinospora cordifolia Miers has been established using Saccharomyces cerevisiae X2180 strain as the in vivo test model. The entire activity could be attributed to the radical scavenging capacity of the preparation, as it did not enhance the expression of the protective enzymes, catalase and superoxide dismutase in the yeast cells. 相似文献
89.
Drosophila nasuta albomicans (with 2n = 6), contains a pair of metacentric neo-sex chromosomes. Phylogenetically these are products of centric fusion
between ancestral sex (X, Y) chromosomes and an autosome (chromosome 3). The polytene chromosome complement of males with
a neo-X- and neo-Y-chromosomes has revealed asynchrony in replication between the two arms of the neo-sex chromosomes. The
arm which represents the ancestral X-chromosome is faster replicating than the arm which represents ancestral autosome. The
latter arm of the neo-sex chromosome is synchronous with other autosomes of the complement. We conclude that one arm of the
neo-X/Y is still mimicking the features of an autosome while the other arm has the features of a classical X/Y-chromosome.
This X-autosome translocation differs from the other evolutionary X-autosome translocations known in certain species ofDrosophila. 相似文献
90.