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11.
We assessed the relationships among HIV-related social and behavioral outcomes resulting from an adolescent-focused HIV structural change initiative in eight urban sites operating Connect-to-Protect coalitions. Over a 4-year period, annual cross-sectional panels of adolescents (N = 2248) completed an audio-computer-assisted interview, providing data on satisfaction with their communities as adolescent-supportive environments, internalized HIV stigma, lifetime HIV-testing, lifetime sexual risk-taking and number of sexual partners in the prior year. We used structural equation modeling to estimate hypothesized links between time since coalition mobilization to our social and behavioral outcomes. Over the 4 years, adolescents perceived their communities to become more supportive (p < .05). Positive perceptions of community support were associated with lower lifetime HIV sexual risk (p < .05). The effect of time on risk behavior was mediated by perceptions of community support. Stigma was unchanged over time. Stigma had damaging effects on risk behavior, effects which were also mediated by perceptions of community support. Special efforts are needed to address the deleterious effect of HIV stigma on high-risk urban adolescents.  相似文献   
12.
Aims: To investigate the value of visceral adipose tissue (VAT) and subcutaneous adipose tissue (SAT) in a cohort of a community’s residents who were diagnosed as pre-diabetes, and to evaluate the association of VAT and SAT with insulin resistance.

Methods: This study was based on cross-sectional analysis of data from 107 adults. VAT and SAT were assessed by computed tomography. Insulin resistance was defined by homeostasis model assessment of insulin resistance >2.69. The relationship of VAT and SAT with insulin resistance were examined by linear regression. Logistic regression was used to analyze the association of VAT and SAT with insulin resistance.

Results: A total of 87 subjects had VAT ≥100?cm2. Thirty-six out of 107 (33.6%) subjects were detected to have insulin resistance, 71 were normal (66.4%), and all had insulin resistance with VAT ≥100?cm2. VAT (r?=?0.378, p?r?=?0.357, p?p?=?.003), but that of SAT was lost.

Conclusion: Pre-diabetic subjects with insulin resistance had elevated levels of VAT. VAT was more strongly associated with insulin resistance than SAT in Chinese subjects with pre-diabetes.  相似文献   
13.
The increase in multidrug resistance among colon cancer cells presents a challenge for the development of effective therapies. Small-molecule analogues of second mitochondria-derived activator of caspase (SMAC) mimetic in association with mixed lineage kinase domain-like protein (MLKL)-pDNA and z-VAD-fmk have shown ideal antitumor effects in colon cancer cells in vitro via induction of RIP3-dependent necroptosis. To achieve synergistic antitumor effects in vivo, liposomes loaded with SMAC mimetic, MLKL-pDNA and z-VAD-fmk have been developed using novel lipid fusion methods to co-localise the molecules of interest within the tumour cells. The co-encapsulation liposome (MLKL-zVAD-BV6-LP) had a high entrapment efficiency of approximately 95% for both zVAD and BV6 and was able to condense MLKL-pDNA very well. The vectors showed good biocompatibility, tumour targeting and small-molecule co-localisation. In a CT26 mouse model, the MLKL-zVAD-BV6-LP exhibited a tumour-suppression rate of over 60% in vivo, which was significantly higher than that of both the null-liposome and coadministration groups. Above all, the co-encapsulation system provided a novel approach to combination tumour therapy.  相似文献   
14.
目的构建体外百草枯(paraquat,PQ)细胞纤维化模型,观察PQ对A549细胞中解整合素-金属蛋白酶17(ADAM17)表达的影响,探讨ADAM17在PQ中毒致肺纤维化中的作用。方法体外培养A549细胞,分为正常对照组、不同浓度PQ组,应用CCK-8检测细胞活力,筛选PQ浓度和时间,显微镜下观察细胞形态,ELISA测定各组纤维化标志物I型胶原(type I collagen,Col I)和纤连蛋白(fibronectin,FN)的表达,建立细胞纤维化模型;免疫细胞化学检测A549细胞中ADAM17的分布情况,RT-PCR和Western blot分别半定量检测ADAM17 mRNA及蛋白水平的表达情况。结果(1)随着PQ浓度增加及作用时间延长,A549细胞活力呈下降趋势,差异有统计学意义(P〈0.05),呈剂量依赖性和时间依赖性。(2)正常的A549细胞融合呈铺路石样生长,排列比较紧密,经PQ诱导后细胞排列较松散,细胞间连接变疏松,部分细胞溶解、死亡。(3)ELISA显示,随PQ浓度增加,Col I和FN表达增强,差异有统计学意义(P〈0.05);随PQ时间延长,Col I和FN表达也逐渐增强,差异有统计学意义(P〈0.05),成功建立PQ细胞纤维化模型。(4)免疫细胞化学显示,ADAM17在A549细胞胞浆表达。(5)RT-PCR和Western blot表明,随着PQ浓度增加,ADAM17 mRNA及蛋白水平表达明显增加,差异有统计学意义(P〈0.05),以PQ 200 umol/L时最为明显。随着PQ作用时间延长,ADAM17 mRNA及蛋白表达水平也明显增加,差异有统计学意义(P〈0.05),在24 h达到高峰。结论百草枯可引起肺泡上皮细胞形态学改变,导致细胞损伤,成功建立细胞的纤维化模型,对A549细胞的毒性作用具有剂量和时间依赖性。ADAM17在PQ诱导的A549细胞中过表达,可能参与了百草枯诱导的肺纤维化过程。  相似文献   
15.
16.
Power estimations are important for optimizing genotype‐phenotype association study designs. However, existing frameworks are designed for common disorders, and thus ill‐suited for the inherent challenges of studies for low‐prevalence conditions such as rare diseases and infrequent adverse drug reactions. These challenges include small sample sizes and the need to leverage genetic annotation resources in association analyses for the purpose of ranking potential causal genes. We present SimPEL, a simulation‐based program providing power estimations for the design of low‐prevalence condition studies. SimPEL integrates the usage of gene annotation resources for association analyses. Customizable parameters, including the penetrance of the putative causal allele and the employed pathogenic scoring system, allow SimPEL to realistically model a large range of study designs. To demonstrate the effects of various parameters on power, we estimated the power of several simulated designs using SimPEL and captured power trends in agreement with observations from current literature on low‐frequency condition studies. SimPEL, as a tool, provides researchers studying low‐frequency conditions with an intuitive and highly flexible avenue for statistical power estimation. The platform‐independent “batteries included” executable and default input files are available at https://github.com/precisionomics/SimPEL .  相似文献   
17.
目的研究锁阳对大鼠前列腺增生(BPH)模型的作用及相关机制研究。方法用雌/雄激素诱导大鼠前列腺增生。按体重将去势3周后大鼠随机分为3组:模型组,锁阳组(3 g·kg-1·d-1),氟他胺组(30 mg·kg-1·d-1),每组10只。另外取10只健康大鼠作为假手术组,模型组和假手术组给等量0. 9%Na Cl,均灌胃给药,每天1次,连续给药45 d。以蛋白免疫印迹检测增殖细胞核抗原(PCNA)蛋白变化;用Cyto Scape3. 5. 1软件构建和分析锁阳"化合物-靶点-前列腺增生"复杂网络。结果给药后,假手术组、模型组、锁阳组的PCNA蛋白表达灰度比值分别是0. 58±0. 11,1. 37±0. 21,0. 94±0. 31,模型组与假手术比较,差异有统计学意义(P <0. 05);锁阳组与模型组比较,差异有统计学意义(P <0. 05)。网络药理学揭示,锁阳直接作用于BPH疾病的靶点有7个,4个新发现的靶点分别为细胞周期素D1(CCND1)、磷脂酰基醇(PIK3CA)、氧化物酶体增殖物激活受体(PPARG)和过氧化物合成酶(PTGS2)。结论锁阳抑制大鼠前列腺增生可能与细胞增殖等通路以及调节细胞周期素D1(CCND1)与磷脂酰基醇(PIK3CA)等蛋白表达相关。  相似文献   
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19.
Peripheral Arterial Occlusive Disease (PAOD) is an aging disease that affects the quality of life of many people by its intermittent claudication and critical limb ischemia presentations. Traditional treatment and management of PAOD are asking patients to make a life change and medication with antiplatelet, statins and cilostazol, which decrease the possibility of clot formation. Our strategy has employed a magnetic Fe3O4-PLGA polymersome to carry the cilostazol into the ischemic area by magnetic attraction following remote-control drug release through low-energy ultrasound exposure. In the animal studies, the cilostazol-loaded Fe3O4-PLGA polymersomes were injected and accumulated at ischemic leg through magnetic attraction. Then, using a clinical-use ultrasound machine the leg was irradiated to forward cilostazol release from the accumulated polymersomes. Dramatically, we found an observable result of bloody flux recovery in the leg after 7?days compared to the non-treated leg that showed no evidence of the blood recovery.  相似文献   
20.
The consequences of once-weekly rifapentine plus isoniazid for 3 months (3HP) against latent tuberculosis infections in hemodialysis patients have not been studied before. This is the first study to evaluate the safety and tolerability of 3HP in this population and revealed a completion rate of 65.4%. The therapy was not associated with hepatotoxicity, but with high rates of adverse events (69.2%).  相似文献   
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