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881.
Self-complementary adeno-associated viral (AAV) vectors expressing human factor IX (hF.IX) have achieved transient or sustained correction of hemophilia B in human volunteers. High doses of AAV2 or AAV8 vectors delivered to the liver caused in several patients an increase in transaminases accompanied by a rise in AAV capsid-specific T cells and a decrease in circulating hF.IX levels suggesting immune-mediated destruction of vector-transduced cells. Kinetics of these adverse events differed in patients receiving AAV2 or AAV8 vectors causing rise in transaminases at 3 versus 8 weeks after vector injection, respectively. To test if CD8+ T cells to AAV8 vectors, which are similar to AAV2 vectors are fully-gutted vectors and thereby fail to encode structural viral proteins, could cause damage at this late time point, we tested in a series of mouse studies how long major histocompatibility (MHC) class I epitopes within AAV8 capsid can be presented to CD8+ T cells. Our results clearly show that depending on the vectors'' genome, CD8+ T cells can detect such epitopes on AAV8''s capsid for up to 6 months indicating that the capsid of AAV8 degrades slowly in mice.  相似文献   
882.
目的:通过社交技能训练让精神分裂症患者明确正确的沟通方式,锻炼自己的交谈能力,学会社会交往技巧,体会人与人之间的关系,学会分析解决社交过程中出现的问题,从而掌握社会交往的技能,防止或延缓发生严重的社会功能衰退。方法:选择早期精神分裂症患者(5年内),在住院治疗达到临床治愈出院后立即开始训练。活动以小组为单位(10人1组)进行,小组成员相对固定。前3个月每个月1次,以后每3个月1次,持续1年。活动过程中以游戏为主导,让组员在游戏中领会人际交往过程中的要领。具体训练方案包括6个方面:①训练一:语言表达能力,正确的沟通方式。②训练二:如何寻找帮助。③训练三:指导患者学习人际交往的基本技巧。④训练四:如何与人打交道。⑤训练五:合作。⑥训练六:社交问题的解决。结果:通过增加对社交时恐惧的暴露及社交技巧训练,对精神分裂症伴发社交恐惧症有效;但对精神分裂症意志活动减退所致社交时主动性不足效果较差。结论:对精神分裂症患者的社交训练应尽早进行,同时在设计精神分裂症社交训练时应加强对患者主动性不足的针对性。  相似文献   
883.
目的:观察芪丹颗粒对博莱霉素致肺纤维化鼠的Ⅰ型前胶原和Ⅲ型前胶原mRNA表达的影响,探讨其作用机制。方法:实验于2004-10/2006-10在山东省医学科学院基础所病理实验室完成。实验材料:清洁级雄性SD大鼠160只,体质量180~210g。氢化可的松琥珀酸钠50mg/支;芪丹(颗粒剂)是由黄芪、丹参、川芎等中草药加工提纯后的粗提取物制成的颗粒剂,10g/包(1g干粉相当于原生药8g)。实验分组:160只SD大鼠按随机区组设计分为正常组20只、模型组40只、芪丹颗粒剂50只、氢化可的松50只。实验干预:正常组20只气管内灌注和灌胃均用生理盐水。其余大鼠经气管内一次性灌注博莱霉素A5按0.25mL左右(5mg/kg体质量)诱导大鼠肺间质纤维化。随机取40只为模型组。取芪丹颗粒剂组和氢化可地松组大鼠各30只,分别从造模后第2天灌注芪丹颗粒剂(3125mg/kg)和腹腔注射氢化可的松(25mg/kg),药物干预后第7,14,28天麻醉下处死动物。两组各余20只分别从造模14d后灌注芪丹颗粒剂和腹腔注射氢化可的松(用量同前),于第28、42天分别处死动物。实验评估:用苏木精-伊红评价肺组织病理学变化和原位杂交方法检测各组大鼠肺Ⅰ型和Ⅲ型前胶原mRNA表达。结果:160只大鼠全部进入结果分析。①大鼠肺脏大体标本观察:对照组肺组织各观察时间点无明显改变,模型组肺组织表面凸凹不平,部分肺叶体积缩小,表面见灰白色结节。氢化可的松组与模型组相似。芪丹颗粒剂组见部分肺叶表面不光滑及大小不等结节。②肺组织病理学观察:模型组7d肺泡腔内大量巨噬细胞淋巴细胞中性粒细胞浸润,肺间质成纤维细胞增殖,28d肺泡结构破坏肺泡内见大量胶原纤维和成纤维细胞。芪丹颗粒剂组肺泡炎及肺纤维化程度均明显轻于模型组和氢化可的松组(P<0.05)。③肺间质纤维化形成中Ⅰ型、Ⅲ型前胶原mRNA表达:原位杂交显示两种前胶原mRNA表达呈动态变化,早期肺泡炎以Ⅲ型前胶原mRNA大量增生为主,晚期纤维化期以Ⅰ型前胶原mRNA增生为主。芪丹颗粒剂组Ⅲ型前胶原mRNA的表达在第14天处于最高,至28d仍维持较高的水平,芪丹颗粒剂组Ⅲ型前胶原mRNA的表达高于模型组和氢化可的松组(P<0.05)。28d,Ⅰ型前胶原mRNA的表达在第二天给药芪丹颗粒剂组和氢化可地松组及第14天给药芪丹颗粒剂组和氢化可的松组组间差异均有显著性(P<0.05)。结论:大鼠肺纤维化的早期以Ⅲ型前胶原mRNA的表达为主,晚期纤维化期以Ⅰ型前胶原mRNA的大量表达为主。芪丹颗粒可减轻博莱霉素诱导的大鼠肺泡炎及肺纤维化的程度,其机制可能通过影响了Ⅰ型和Ⅲ型前胶原mRNA的代谢和表达,从而减慢肺间质纤维化的进程。芪丹颗粒对肺间质纤维化有治疗作用,且优于氢化可的松。  相似文献   
884.
Transport of glucose into neuronal cells is predominantly mediated by the glucose transporters GLUT1 and GLUT3. In addition, GLUT8 is expressed in some regions of the brain. By in situ hybridization we detected GLUT8-mRNA in hippocampus, thalamus, and cortex. However, its cellular and physiological function is still unknown. Thus, GLUT8 knockout (Slc2a8 -/-) mice were used for a screening approach in the modified hole board (mHB) behavioral test to analyze the role of GLUT8 in the central nervous system. Slc2a8 -/- mice showed increased mean velocity, total distance traveled and performed more turns in the mHB test. This hyperactivity of Slc2a8 -/- mice was confirmed by monitoring locomotor activity in the home cage and voluntary activity in a running wheel. In addition, Slc2a8 -/- mice showed increased arousal as indicated by elevated defecation, reduced latency to the first defecation and a tendency to altered grooming. Furthermore, the mHB test gave evidence that Slc2a8 -/- mice exhibit a reduced risk assessment because they performed less rearings in an unprotected area and showed significantly reduced latency to stretched body posture. Our data suggest that behavioral alterations of Slc2a8 -/- mice are due to dysfunctions in neuronal processes presumably as a consequence of defects in the glucose metabolism.  相似文献   
885.
Objective: To validate a previously published prediction model for recurrent early-onset preeclampsia (PE). Methods: We included 229 pregnant women with a history of early-onset PE and computed their risk using the prediction model, compared the predicted risk to their pregnancy outcomes and assessed performance of the model. Results: Early-onset PE recurred in 6.6% of participants. The area under the receiver operating characteristic curve was 59% (95% CI: 45–73). The model created groups that were only moderately different in terms of their risk. Conclusions: The model’s discriminate ability was poor and predictive performance insufficient to classify women into relevant risk groups.  相似文献   
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888.

Introduction

Antiretroviral therapy (ART) monitoring using viral load (VL) testing is challenging in high-burden, limited-resources settings. Chemokine IP-10 (interferon gamma-induced protein 10) strongly correlates with human immunodeficiency virus (HIV) VL. Its determination could serve to predict virological failure (VF) and to triage patients requiring VL testing. We assessed the field performance of a semi-quantitative IP-10 lateral flow assay (LFA) for VF screening in South Africa, and the cost-effectiveness of its implementation in Mozambique.

Methods

A cross-sectional study was conducted between June and December 2021 in three primary health clinics in the Western Cape. Finger prick capillary blood was collected from adults on ART for ≥1 year for direct application onto the IP-10 LFA (index test) and compared with a plasma VL result ≤1 month prior (reference test). We estimated the area under the receiver operating characteristic curves (AUC), sensitivity and specificity, to evaluate IP-10 LFA prediction of VF (VL>1000 copies/ml). A decision tree model was used to investigate the cost-effectiveness of integrating IP-10 LFA combined with VL testing into the current Mozambican ART monitoring strategy. Averted disability-adjusted life years (DALYs) and HIV acquisitions, and incremental cost-effectiveness ratios were estimated.

Results

Among 209 participants (median age 38 years and 84% female), 18% had VF. Median IP-10 LFA values were higher among individuals with VF compared to those without (24.0 vs. 14.6; p<0.001). The IP-10 LFA predicted VF with an AUC = 0.76 (95% confidence interval (CI) 0.67–0.85), 91.9% sensitivity (95% CI 78.1–98.3) and 35.1% specificity (95% CI 28.0–42.7). Integrating the IP-10 LFA in a setting with 20% VF prevalence and 61% VL testing coverage could save 13.0% of costs and avert 14.9% of DALYs and 55.7% new HIV acquisitions. Furthermore, its introduction was estimated to reduce the total number of routine VL tests required for ART monitoring by up to 68%.

Conclusions

The IP-10 LFA is an effective VF triage test for routine ART monitoring. Combining a highly sensitive, low-cost IP-10 LFA-based screening with targeted VL confirmatory testing could result in significant healthcare quality improvements and cost savings in settings with limited access to VL testing.  相似文献   
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