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41.
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CT diagnosis of idiopathic aneurysms of the thoracic systemic veins   总被引:3,自引:0,他引:3  
Three patients with idiopathic aneurysms of the superior vena cava, left innominate vein, and inferior vena cava are presented. The advantages of CT over other diagnostic modalities are discussed.  相似文献   
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OBJECTIVE AND DESIGN: The intensity of replication of CCR5-using HIV-1 strains is highly dependent on the number of CCR5 molecules on the surface of CD4-positive T cells. The molecular mechanisms responsible for this phenomenon remained so far unclear. As CCR5 co-receptors are coupled to G alpha i and G alpha q proteins, we tested the hypothesis that the activation triggered through these proteins secondary to the interaction between the viral envelope and CCR5 could account for the effect of the level of CCR5 expression on HIV-1 production. METHODS: We transduced the wild-type or a G-protein signalling-defective CCR5 gene into CD4/CCR5 HOS cells and peripheral blood mononuclear cells. The effect on cell activation in presence of a CCR5-binding chemokine and on HIV infection was monitored by measuring calcium mobilization and p24 antigen production, respectively. The role of G alpha i protein signalling was tested by adding pertussis toxin to the cell cultures or by transfecting small interfering (si) RNAs into the HOS cells. RESULTS: The over-expression of the wild-type form, but not of a G-protein signalling-defective form of CCR5, on the surface of CCR5 expressing peripheral blood mononuclear cells markedly increased their infectability. In addition, both pertussis toxin and G alpha i 1-specific siRNA drastically inhibited R5 infection. CONCLUSIONS: The signalling through G alpha i-protein induced upon R5 virion binding to CCR5 is responsible for the difference in HIV-1 infectability between CD4-positive T cells expressing low or high levels of cell surface CCR5 density. This observation sheds new light on the physiopathology of HIV infection, and opens new therapeutic opportunities targeting G alpha i signalling.  相似文献   
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OBJECTIVE: To examine the relationship between plasma levels of apolipoproteins C3 (APOC3) and E (APOE) and the presence of lipid and carbohydrate metabolism abnormalities or clinical signs of lipodystrophy in HIV-1-infected patients started with a protease-inhibitor-containing antiretroviral therapy. METHODS: The Aproco (Antiproteases Cohort) Study enrolled 1,181 HIV-1-infected adults in 47 French healthcare centres from May 1997 to June 1998. From December 1998 through July 1999, the APROCO-Metabolic Complications (APROCO-MC) cross-sectional study was performed at the month 20 visit for those patients enrolled in 1997 and at the month 12 visit for those enrolled in 1998. The current analysis presents results from a subset of patients who had undergone additional tests to measure APOC3 and APOE in order to study their relationship with metabolic syndrome (n=157) and abnormal results in an oral glucose tolerance test (n=135). RESULTS: Increases in triglycerides and non-high-density lipoprotein (HDL) cholesterol were associated with significantly higher levels of APOC3, in both Lp B (lipoproteins containing apolipoprotein B) and Lp non-B (lipoproteins free of apolipoprotein B), and a significant higher level of APOE Lp B. APOC3 and APOC3 Lp non-B were increased when glucose metabolism abnormalities were more severe. The presence of a metabolic syndrome was associated with increased plasma APOC3, APOC3 Lp B and APOC3 Lp non-B levels. In a multiple regression analysis, high levels of APOC3 in Lp B and APOC3 Lp non-B were associated with the presence of clinical signs of lipodystrophy, even after adjustment for triglycerides and HDL-cholesterol levels. CONCLUSIONS: Lipid and/or glucose metabolism abnormalities in treated HIV-1-infected patients are associated with increased levels of APOC3 and, to a lesser extent, APOE plasma concentrations. Increased values are also related to clinical signs of insulin resistance and lipodystrophy.  相似文献   
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Recent data from clinical trials investigating the efficacy of enfuvirtide, a fusion inhibitor, in treatment-experienced patients have revealed that the addition of enfuvirtide (ENF) to an active boosted protease inhibitor regimen doubles the rate of virological response. At week 48 of the TORO studies, 55% of patients previously naive to and receiving lopinavir/ritonavir (LPV/r) with ENF achieved a viral load of <400 copies/mL compared with 24% of patients treated with LPV/r alone. At week 24 of the RESIST studies, 70% of previously ENF-naive patients who took both ENF and tipranavir/ritonavir (TPV/r) achieved a >or=1 log10 reduction in viral load compared with 37% of such patients treated with TPV/r alone. Similarly, concomitant use of TMC114/ritonavir (TMC114/r) with ENF, compared with TMC114/r alone, increased the number of patients with <50 copies/mL from 46% to 64% in a combined 24-week analysis from the POWER trials. Data from these trials suggest that combining one agent from a new class with a new agent from a previously exposed class offers a greater chance of achieving full virological control than either type of agent alone. Undetectable viraemia should be the primary objective for treatment-experienced patients requiring a switch in therapy, and the present data support the combination of an active boosted protease inhibitor with an agent from a new class (e.g., ENF) for triple-class-experienced patients.  相似文献   
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Huy TT  Sall AA  Reynes JM  Abe K 《Virus genes》2008,36(2):299-305
Although it is known that Cambodia is one of the high endemic area of hepatitis B virus (HBV) infection, molecular characterization of HBV circulating in this country has not been reported. In this study, pre-S gene of HBV from 12 Cambodian patients was sequenced. Phylogenetic analysis based on the pre-S gene sequence revealed that 8 out of 12 isolates (66.7%) belonged to HBV/C1 and remaining four (33.3%) were HBV/B4. Furthermore, complete genomic sequences were also determined for three Cambodian HBV isolates. They all comprised of 3,215 bp long and two of them belonged to subgenotype B4, which had recombination event with genotype C in the precore/core gene confirmed by SimPlot and BootScanning analyses. Our results showed that both HBV strains belonged to subgenotypes B4 and C1, which are circulating in this country. This is the first report on molecular characterization of the HBV prevalent in Cambodia.  相似文献   
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Purpose

We retrospectively examined the potential effect on overall survival (OS) of delaying radiotherapy to administer neoadjuvant therapy in unresected glioblastoma patients.

Patients and methods

We compared OS in 119 patients receiving neoadjuvant therapy followed by standard treatment (NA group) and 96 patients receiving standard treatment without neoadjuvant therapy (NoNA group). The MaxStat package of R identified the optimal cut-off point for waiting time to radiotherapy.

Results

OS was similar in the NA and NoNA groups. Median waiting time to radiotherapy after surgery was 13 weeks for the NA group and 4.2 weeks for the NoNA group. The longest OS was attained by patients who started radiotherapy after 12 weeks and the shortest by patients who started radiotherapy within 4 weeks (12.3 vs 6.6 months) (P?=?0.05). OS was 6.6 months for patients who started radiotherapy before the optimal cutoff of 6.43 weeks and 19.1 months for those who started after this time (P?=?0.005). Patients who completed radiotherapy had longer OS than those who did not, in all 215 patients and in the NA and NoNA groups (P?=?0.000). In several multivariate analyses, completing radiotherapy was a universally favorable prognostic factor, while neoadjuvant therapy was never identified as a negative prognostic factor.

Conclusion

In our series of unresected patients receiving neoadjuvant treatment, in spite of the delay in starting radiotherapy, OS was not inferior to that of a similar group of patients with no delay in starting radiotherapy.
  相似文献   
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