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581.
GB virus C (GBV-C) is an apathogenic virus that has been shown to inhibit HIV replication. This study examined the prevalence and correlates of GBV-C infection and clearance in three cohorts of pregnant women in Thailand. The study population consisted of 1,719 (1,387 HIV-infected and 332 HIV-uninfected) women from three Bangkok perinatal HIV transmission studies. Stored blood was tested for GBV-C RNA, GBV-C antibody, and if RNA-positive, genotype. Risk factors associated with the prevalence of GBV-C infection (defined as presence of GBV-C RNA and/or antibody) and viral clearance (defined as presence of GBV-C antibody in the absence of RNA) among women with GBV-C infection were examined using multiple logistic regression. The prevalence of GBV-C infection was 33% among HIV-infected women and 15% among HIV-uninfected women. GBV-C infection was independently associated (AOR, 95% CI) with an increasing number of lifetime sexual partners (referent-1 partner, 2 partners [1.60, 1.22-2.08], 3-10 partners [1.92, 1.39-2.67], >10 partners [2.19, 1.33-3.62]); injection drug use (5.50, 2.12-14.2); and HIV infection (3.79, 2.58-5.59). Clearance of GBV-C RNA among women with evidence of GBV-C infection was independently associated with increasing age in years (referent <20, 20-29 [2.01, 1.06-3.79] and ≥30 [3.18, 1.53-6.60]), more than 10 lifetime sexual partners (3.05, 1.38-6.75), and HIV infection (0.29, 0.14-0.59). This study found that GBV-C infection is a common infection among Thai women and is associated with HIV infection and both sexual and parenteral risk behaviors.  相似文献   
582.
583.
OBJECTIVES: To determine the severity of injection site reactions (ISRs), patient quality of life (QoL) and preference when enfuvirtide is administered by the Biojector (Bioject, Medical Technologies, Inc., Tualatin, OR, USA) relative to standard needles. METHODS: A total of 201 HIV-positive patients on stable enfuvirtide-based therapy (n=184) or initiating such therapy (n=17) were evaluated prospectively after switching from standard needles to the Biojector system. Patients used needles for a minimum of 2 weeks prior to switching to the Biojector. Questionnaires to assess the incidence and severity of ISRs (31-item score) and QoL [Medical Outcomes Study HIV Health Survey (MOS-HIV)] were administered at baseline and following a minimum of 14 days of Biojector use. RESULTS: The median changes in ISR score and number of ISRs following a median of 1.0 month [interquartile range (IQR) 0.9, 1.3] of Biojector use were -3 (IQR -7, 1) and -1 (IQR -3, 1), respectively. The severity of pain (P<0.0001), induration (P<0.0001), pruritus (P<0.0001), nodules (P<0.0001) and erythema (P<0.0001) all decreased with the Biojector. Administration of enfuvirtide with the Biojector was associated with an improved patient QoL (P<0.0001), and was preferred by 72% of patients. CONCLUSIONS: Compared with needles, the Biojector was associated with a decreased severity of ISRs and improved QoL in patients taking enfuvirtide.  相似文献   
584.
585.

Introduction

Hyperlipidaemia is a recognized complication of HIV antiretroviral therapy. The interactions among HIV, viral hepatitis, antiretroviral therapies and lipids are poorly understood.

Methods

Ontario HIV Treatment Network Cohort Study participants with at least one lipid level after highly active antiretroviral therapy (HAART) initiation were assessed. Hepatitis B virus (HBV)‐ and hepatitis C virus (HCV)‐coinfected patients were identified by serology or chart review. HCV antiviral recipients, diabetics and those on lipid‐lowering drugs at baseline were excluded from the study. Factors associated with a decreased risk of grade 3 or 4 hyperlipidaemia or lipid‐lowering drug use were assessed by multivariate logistic regression.

Results

A total of 1587 HIV‐monoinfected, 190 HIV/HBV‐coinfected and 255 HIV/HCV‐coinfected patients were evaluated. Most were male (85–92% for the 3 groups evaluated: HIV, HIV/HBV, HIV/HCV). The median [interquartile range (IQR)] age at HAART initiation was 48 (44–56) years and was similar between groups. The median (IQR) CD4 count at HAART initiation was 245 (120–370) cells/μL in HIV‐monoinfected participants, 195 (110–330) cells/μL in HIV/HBV‐coinfected participants and 268 (140–409) cells/μL in HIV/HCV‐coinfected participants. Factors associated with a decreased risk of grade 3 or 4 hyperlipidaemia or lipid‐lowering drug use included HIV/HCV coinfection [odds ratio (OR) 0.46; 95% confidence interval (CI) 0.34, 0.61; P<0.0001], HIV/HBV coinfection (OR 0.74; 95% CI 0.55, 0.99; P=0.04), year of starting HAART after 2004 vs. 1997 or earlier (OR 0.37; 95% CI 0.29, 0.48; P<0.0001) and year of starting HAART between 1998 and 2003 vs. 1997 or earlier (OR 0.75; 95% CI 0.61, 0.92; P<0.01). Factors associated with increased risk included age (OR 1.55; 95% CI 1.39, 1.72; per 10 years, P<0.0001) and male gender (OR 1.84; 95% CI 1.36, 2.48; P<0.0001).

Conclusions

HIV/HCV and to a lesser extent HIV/HBV coinfections are protective against HAART‐related hyperlipidaemia.  相似文献   
586.
Baldwin  GC; Benveniste  EN; Chung  GY; Gasson  JC; Golde  DW 《Blood》1993,82(11):3279-3282
We previously showed the presence of receptors for granulocyte- macrophage colony-stimulating factor (GM-CSF) on tumor tissues and tumor cell lines that are derived from the neural crest. To determine whether normal neural cells express functional GM-CSF receptors, we isolated and analyzed primary rat brain cells, including microglia, astrocytes, and oligodendrocytes. Scatchard analysis of equilibrium binding of 125I-GM-CSF to primary rat oligodendrocytes showed an average of 1,110 GM-CSF binding sites per cell, with a kd of 20 pmol/L. In six separate experiments, no specific binding was detectable on the astrocyte population. Microglia were used in competitive binding experiments with oligodendrocytes, and addition of microglia did not increase the specific binding of labeled ligand to oligodendrocytes. In dose-response assays, we measured 3H-thymidine uptake in rat oligodendrocytes, microglia and control murine 32D cells stimulated with various concentrations of GM-CSF. Over concentration ranges of 0.025 to 1000 pmol/L, cell proliferation and peak 3H-thymidine incorporation was observed at approximately 30 pmol/L for both the control cells and the oligodendrocytes. However, the microglial cells did not proliferate in response to GM-CSF. These data indicate the presence of a functional receptor for GM-CSF on primary rat oligodendrocytes, and suggest that hematopoietic growth factors such as GM-CSF may play a role in nerve cell development, function, or response to injury.  相似文献   
587.
目的:目前已知端粒酶活性的丧失及其增殖相关基因表达的改变是造成多种成体干细胞体外复制和扩增受限的主要原因,而端粒酶反转录酶对端粒酶活性起关键作用。体外分离培养人胚胎、少儿、成人3种不同皮肤来源的表皮干细胞,对比观察不同发育阶段端粒酶反转录酶表达的差异。方法:实验于2005-09/2007-04在南昌大学第一附属医院烧伤研究所完成。①对象:因创伤等原因致意外流产的妊娠24~26周龄胎儿皮肤标本,4~12周岁少儿及25~45岁成年人烧伤整形植皮手术剩余皮片标本,分别由南昌大学第一附属医院产科、烧伤科提供,产妇与烧伤患者对治疗及实验均知情同意,实验经医院医学伦理委员会批准。②实验方法:取胎儿、少儿和成年人的全层皮肤,用胰蛋白酶和EDTA联合消化法分离表皮,胶原快速贴附法纯化人表皮干细胞,用未黏附的角质细胞作为对照,以含表皮生长因子、角质细胞无血清培养液组成的表皮干细胞培养基进行体外培养。③实验评估:通过β_1整合素、角蛋白19、p63免疫细胞化学染色对培养细胞进行鉴定,计算克隆形成率。以免疫细胞化学染色法和图像定量分析法检测3种不同皮肤来源的表皮干细胞端粒酶反转录酶的表达差异。结果:①细胞生长特征:分离培养的人表皮干细胞呈明显克隆性生长,克隆形成率高于角质细胞对照组(P<0.05)。②表皮干细胞的鉴定:细胞克隆经免疫细胞化学染色后,β_1整合素、角蛋白19、p63均呈阳性表达。③端粒酶反转录酶免疫细胞化学染色及定量表达:不同皮肤来源的表皮干细胞端粒酶反转录酶均呈阳性,但表达强度不同,人胚胎>少儿>成人。3种皮肤来源的表皮干细胞平均吸光度值和阳性面积值均随年龄增加而逐渐降低,人胚胎>少儿>成人(P<0.05)。结论:人胚胎、少儿、成人皮肤来源的表皮干细胞均有端粒酶反转录酶表达,其表达强度依次减弱。提示诱导和增强端粒酶反转录酶的表达对维持表皮干细胞在体外自我更新和增殖能力可能具有重要意义。  相似文献   
588.
4种氟喹诺酮液体制剂降解析因试验   总被引:10,自引:0,他引:10  
张秋生  白政忠  关大卫 《药学学报》1997,32(12):931-933
模拟4种喹诺酮输液剂及滴眼剂在不同pH和离子强度的条件下,考察了光、pH以及离子强度分别对诺氟沙星(NFX)、氧氟沙星(OFX)、环丙沙星(CPX)、洛美沙星(LEMX)降解程度的影响,应用23析因试验方法,经F检验确证:NFX,OFX,CPX,LEMX离子强度影响均不显著,光影响均极显著;pH对NFX和LEMX影响不显著,对OFX和CPX影响极显著;OFX和CPX由光及pH二因素交互作用影响极显著,NFX和LEMX由光及pH二因素交互作用影响不显著。  相似文献   
589.
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