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991.
We designed, synthesized, and identified UIC-94017 (TMC114), a novel nonpeptidic human immunodeficiency virus type 1 (HIV-1) protease inhibitor (PI) containing a 3(R),3a(S),6a(R)-bis-tetrahydrofuranylurethane (bis-THF) and a sulfonamide isostere which is extremely potent against laboratory HIV-1 strains and primary clinical isolates (50% inhibitory concentration [IC(50)], approximately 0.003 micro M; IC(90), approximately 0.009 micro M) with minimal cytotoxicity (50% cytotoxic concentration for CD4(+) MT-2 cells, 74 micro M). UIC-94017 blocked the infectivity and replication of each of HIV-1(NL4-3) variants exposed to and selected for resistance to saquinavir, indinavir, nelfinavir, or ritonavir at concentrations up to 5 micro M (IC(50)s, 0.003 to 0.029 micro M), although it was less active against HIV-1(NL4-3) variants selected for resistance to amprenavir (IC(50), 0.22 micro M). UIC-94017 was also potent against multi-PI-resistant clinical HIV-1 variants isolated from patients who had no response to existing antiviral regimens after having received a variety of antiviral agents. Structural analyses revealed that the close contact of UIC-94017 with the main chains of the protease active-site amino acids (Asp-29 and Asp-30) is important for its potency and wide spectrum of activity against multi-PI-resistant HIV-1 variants. Considering the favorable pharmacokinetics of UIC-94017 when administered with ritonavir, the present data warrant that UIC-94017 be further developed as a potential therapeutic agent for the treatment of primary and multi-PI-resistant HIV-1 infections.  相似文献   
992.
Cognitive impairment is common in Parkinson's disease (PD). There is a critical need for a brief, standard cognitive screening measure for use in PD trials whose primary focus is not on cognition. The Parkinson Study Group (PSG) Cognitive/Psychiatric Working Group formed a Task Force to make recommendations for a cognitive scale that could screen for dementia and mild cognitive impairment in clinical trials of PD where cognition is not the primary outcome. This Task Force conducted a systematic literature search for cognitive assessments previously used in a PD population. Scales were then evaluated for their appropriateness to screen for cognitive deficits in clinical trials, including brief administration time (<15 minutes), assessment of the major cognitive domains, and potential to detect subtle cognitive impairment in PD. Five scales of global cognition met the predetermined screening criteria and were considered for review. Based on the Task Force's evaluation criteria the Montreal Cognitive Assessment (MoCA), appeared to be the most suitable measure. This Task Force recommends consideration of the MoCA as a minimum cognitive screening measure in clinical trials of PD where cognitive performance is not the primary outcome measure. The MoCA still requires further study of its diagnostic utility in PD populations but appears to be the most appropriate measure among the currently available brief cognitive assessments. Widespread adoption of a single instrument such as the MoCA in clinical trials can improve comparability between research studies on PD. © 2010 Movement Disorder Society  相似文献   
993.
We present the clinical, biochemical, and molecular findings of three Greek patients with tyrosine hydroxylase (TH) deficiency. All patients presented with a severe clinical phenotype characterized by prominent motor delay, infantile parkinsonism, oculogyric crises, and signs of autonomic dysfunction. Cerebrospinal fluid analysis disclosed reduced dopamine metabolites and normal pterins. Response to levodopa was favorable though not dramatic. All patients were homozygous for a previously reported mutation (p.L236P). SNP haplotype analysis was consistent with a common ancestral mutation, thus indicating a founder effect in Greek patients with TH deficiency. © 2010 Movement Disorder Society  相似文献   
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995.
Previously, we have shown that mice deficient in either vasoactive intestinal peptide (VIP) or pituitary adenylate cyclase‐activating polypeptide (PACAP) exhibit specific deficits in the behavioral response of their circadian system to light. In this study, we investigated how the photic regulation of the molecular clock within the suprachiasmatic nucleus (SCN) is altered by the loss of these closely‐related peptides. During the subjective night, the magnitude of the light‐induction of FOS and phosphorylated mitogen‐activated protein kinase (p‐MAPK) immunoreactive cells within the SCN was significantly reduced in both VIP‐ and PACAP‐deficient mice when compared with wild‐type mice. The photic induction of the clock gene Period1 (Per1) in the SCN was reduced in the VIP‐ but not in the PACAP‐deficient mice. Baselines levels of FOS, p‐MAPK or Per1 in the night were not altered by the loss of these peptides. In contrast, during the subjective day, light exposure increased the levels of FOS, p‐MAPK and Per1 in the SCN of VIP‐deficient mice, but not in the other genotypes. During this phase, baseline levels of these markers were reduced in the VIP‐deficient mice compared with untreated controls. Finally, the loss of either neuropeptide reduced the magnitude of the light‐evoked increase in Per1 levels in the adrenals in the subjective night without any change in baseline levels. In summary, our results indicate that both VIP and PACAP regulate the responsiveness of cells within the SCN to the effects of light. Furthermore, VIP, but not PACAP, is required for the appropriate temporal gating of light‐induced gene expression within the SCN.  相似文献   
996.
997.
AIM:To study the association between Helicobacter pylori(H.pylori)infection and autoimmune type atrophic gastritis. METHODS:Twenty-three patients with different grades of atrophic gastritis were analysed using enzyme immunoassay-based serology,immunoblot-based serology,and histology to reveal a past or a present H.pylori infection.In addition,serum markers for gastric atrophy(pepsinogenⅠ,pepsinogenⅠ/Ⅱand gastrin)and autoimmunity[parietal cell antibodies(PCA), and intrinsic factor(IF),antibodies]were determi...  相似文献   
998.
AIM: To investigate the signifi cance of ileocolonoscopy with histology in the evaluation of post-transplantation persistent diarrhea (PD). METHODS: We retrospectively reviewed all records of renal transplant patients with PD, over a 3-year period. All patients were referred for ileocolonoscopy with biopsy, following a negative initial diagnostic work up. Clinical and epidemiological data were compared between cases with infectious or drug-induced diarrhea. RESULTS: We identif ied 30 episodes of PD in 23 renaltransplant patients (1-3 cases per patient). There were 16 male patients and the mean age at the time of PD was 51.4 years. The average time from transplantation to a PD episode was 62.3 ± 53.2 mo (range 1-199 mo). Ileocolonoscopy detected mucosal abnormalities in 19 cases, whereas the intestinal mucosa appeared normal in 11 cases. Histological examination achieved a specific diagnosis in 19/30 cases (63.3%). In nine out of 11 cases (82%) with normal endoscopic appearance of the mucosa, histological examination of blinded biopsies provided a specif ic diagnosis. The etiology of PD was infectious in 11 cases (36.6%), drug-related in 10 (33.3%), of other causes in three (10%), and of unknown origin in six cases (20%). Infectious diarrhea occurred in significantly longer intervals from transplantation compared to drug-related PD (85.5 ± 47.6 mo vs 40.5 ± 44.8 mo, P < 0.05). Accordingly, PD due to drug-toxicity was rarely seen after the f irst year post-transplantation. Clinical improvement followed therapeutic intervention in 90% of cases. Modif ication of immunosuppressive regimen was avoided in 57% of patients. CONCLUSION: Early ileocolonoscopy with biopsies from both affected and normal mucosa is an important adjunctive tool for the etiological diagnosis of PD in renal transplant patients.  相似文献   
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