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11.
HCV selection and HVR1 evolution in a chimpanzee chronically infected with HCV-1 over 12 years. 总被引:1,自引:0,他引:1
Ling Lu Nakano Tatsunori Chunhua Li Sana Waheed Fengxiang Gao Betty H Robertson 《Hepatology research》2008,38(7):704-716
Aim: To study hepatitis C virus (HCV) selection and hypervariable region-1 (HVR1) evolution in a chimpanzee chronically infected with HCV-1 over 12 years after inoculation with a human factor VIII concentrate contaminated with HCV. Methods: From the inoculum, the earliest chimpanzee plasma and 12 annual plasma samples, HCV fragments including HVR1 were amplified followed by cloning and sequencing. Results: Five HCV subtypes - 1a, 1b, 2a, 2b, 3a - and multiple 1a strains were identified in the inoculum. Two 1a strains were found in the earliest chimpanzee sample, while a single HCV-1 strain was detected in the 12 annual samples. None of the chimpanzee sequences were identical to those found in the inoculum. Over 12 years, HVR1 patterns changed irregularly, but a few patterns showed identical nucleotide or amino acid sequences. In the last three years, the variety of HVR1 patterns decreased, while the proportion of major patterns increased. These corresponded to a higher virus load and a lower number of amino acid substitutions. Simultaneously, the HVR1 sequences became more similar to the consensus sequence of the 1a subtype. Conclusion: HCV selection was observed from the inoculum to the inoculated chimpanzee and from the early acute hepatitis to the persistent chronic infection. The selection occurred at three levels: among subtypes after transmission, among isolates during acute hepatitis and among quasispecies in chronic infection. 相似文献
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Sonal Bhandari Sravani Sana Vandana Lahoti Ramya Tokala Nagula Shankaraiah 《RSC advances》2020,10(27):16101
Herein, we report a facile tandem approach for the synthesis of both spiro-oxindole-fused pyrroloindolines and benzofurano-pyrrolidines via a Lewis acid-catalyzed domino ring-opening with concomitant ring annulation using activated spiro-aziridines and heteroarenes. This method offers a new class of novel spiro-fused polycyclic pyrrolidines in a one-pot and sustainable manner with good yields and high diastereoselectivity. In addition, the structure of 3d was confirmed by single X-ray crystallography analysis.Herein, we report a facile tandem approach for the synthesis of both spiro-oxindole-fused pyrroloindolines and benzofurano-pyrrolidines via a Lewis acid-catalyzed domino ring-opening annulation using activated spiro-aziridines and heteroarenes. 相似文献
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Shiekh Tanveer Ahmad Wani Arjumand Amlesh Seth Sana Nafees Summya Rashid Nemat Ali Oday O. Hamiza Sarwat Sultana 《Urologic oncology》2013,31(7):1350-1357
The progressive increase in sporadic renal cell carcinoma (RCC) observed in industrialized countries supports the opinion that certain carcinogens present in the environment (tobacco smoke, drugs, pollutants, and dietary constituents) may affect the occurrence and progression of this disease in developing countries like India. The polymorphism of the enzymes involved in metabolism of such environmental factors may, therefore, confer variable propensity to RCC. The possible association between RCC and a polymorphism of the CYP1A1 and CYP2D6 genes specific to the Indian population was examined using peripheral blood DNA from 196 RCC cases and 250 population controls with detailed data of clinicopathologic characteristics for the disease. The CYP1A1 (val) “variant” genotype, which contains at least 1 copy of the CYP1A1 variant alleles, was found to be associated with a 2.03-fold [GG ver. AA/AG, unadjusted OR = 2.03; 95%CI = 1.233–3.342; P = 0.005] increase in the risk of RCC. There was also a significant association (ptrend = 0.034) between higher frequency of RCC subjects containing at least of copy of the CYP1A1 (val) “variant” genotype with III or IV Fuhrman's grade. Whereas, the CYP2D6 polymorphism did not show any association with RCC risk [TT ver. CT/CC, unadjusted OR = 95%CI = 1.233–3.342; P = 0.005]. There was a significant association (ptrend = 0.001) between the poor metabolizer CYP2D6 (TT) and progression towards higher pathological stage of RCC. Our data demonstrate for the first time a significant association between pharmacogenetic polymorphisms of CYP1A1 and risk of RCC development in the Indian population. The findings suggest that inter-individual variation in the phase I metabolic enzymes involved in the fictionalization and detoxification of specific xenobiotics is an important susceptibility factor for development and progression of RCC in Indians. 相似文献
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Isamu Saito Takaa Asano Chikayuki Ochiai Kintomo Takakura Akira Tamura Keiji Sana 《Neurological research》2013,35(4):29-47
The effect of Nizofenone (Y-9179), a verebral protective agent, on delayed ischemic neurological deficits following subarachnoid hemorrhage (SAH) due to aneurysmal rupture was investigated by a cooperative double-blind clinical trial. Delayed ischemic neurological deficits following SAH are closely associated with the occurrence of vasospasm, and the effectiveness of any cerebral protective agent depends on sufficient coverage by the drug over the period around the onset of ischemic insult. Therefore, the study was designed so that the effect of Nizofenone could be analyzed in terms of these two factors.In patients admitted within day 9 of SAH, drug administration was immediately initiated and continued for 5 days. When delayed ischemic neurological deficits occurred, angiography was carried out to confirm the presence of vasospasm, and then drug administration was extended for an additional 5 days. Ten of the 100 cases enlisted in the study were excluded prior to code-breaking because of the occurrence of severe complications not related to vasospasm.Out of the 42 cases of the Nizofenone group and 48 of the placebo group, 25 and 29 developed vasospasm, respectively. Thus Nizofenone did not prevent vasospasm. Of the 25 cases of the Nizofenone group with vasospasm, 13 cases received sufficient drug coverage around the onset of vasospasm. The placebo group, the total Nizofenone group, and the Nizofenone group with sufficient drug coverage were stratified according to the occurrence of vasospasm. The disability status index one month after admission and the neurological functions, such as motor and speech functions, of each group were then compared. In patients who developed vasospasm, only the Nizofenone group with sufficient drug coverage had a significantly better outcome than the placebo group (p < 0.05). No particular side effect of Nizofenone was observed.Thus, the results indicate that Nizofenone may be useful in the therapy of delayed ischemic neurological deficits following SAH, although the effect of the drug may be considerably influenced by the timing of its administration. 相似文献