Reduction of human immunodeficiency virus-infected cells from donor blood by leukocyte filtration

Several filters for leukocyte removal were evaluated in terms of their ability to reduce the cell-associated human immunodeficiency virus (HIV) load in units of blood either inoculated in vitro with lymphocytes from a chronically infected cell line or collected directly from seropositive donors. Filtration of the experimentally inoculated units of blood resulted in a 5.9 log 10 mean reduction (95% confidence interval:7.4-4.5) of tissue culture infectious units (TCIU) as assayed by end-point titration using the coculture assay. Filtration of the units of blood from anti-HIV positive donors lowered the infectivity by over 2 logs, as detected by the coculture and polymerase chain reaction (PCR) techniques. However, residual cell-associated virus was detected in the majority of experiments. Clinical studies are warranted to determine if leukocyte filtration of blood will reduce the risk of transfusion transmitted viral infections.     

人脐静脉间充质干细胞原代培养换液频度与细胞增殖生长的关系

目的:体外分离培养人脐静脉内皮及内皮下间充质干细胞,观察采用不同的换液频度与细胞增殖和生长的关系。方法:实验于2006-03/11在辽宁医学院解剖学实验室完成。①选取正常健康产妇顺产或剖宫产的新生儿脐带,由辽宁医学院附属第一医院提供,产妇及其家属均知情同意。②根据更换细胞培养液时间的不同,分为接种后每24h,48h,72h更换培养液组。③无菌条件下将脐带用预热的磷酸盐缓冲液充分洗涤去血渍,从脐静脉一端插入留置针,用预热的磷酸盐缓冲液冲净静脉腔血,止血钳夹闭另一端,采用胶原酶消化法分离人脐静脉内皮及内皮下细胞,取消化30min的细胞悬液进行贴壁培养,以1×108L-1密度接种于24孔培养板中,每孔的细胞数和培养液量相同,按实验设计分组的时间方法更换培养液。④各组自培养24h开始,每天分别取各组细胞4孔,以噻唑蓝比色法测定生长曲线。并采用免疫细胞化学方法对分离的细胞进行表面抗原鉴定。结果:①间充质干细胞的形态学观察:原代培养1周,细胞以梭形细胞为主。传代培养2h细胞开始贴壁变形,24h基本完成贴壁,48h可见部分已贴壁的细胞开始分裂增殖,细胞形态多样,呈椭圆形、梭形、三角形等。5～7d贴壁细胞可见多核的成纤维细胞样。在细胞生长增生过程中,接种后每24h更换培养液组细胞增殖明显,生长状态均最好;接种后每48h更换培养液组次之;接种后每72h更换培养液组细胞增殖较慢,细胞生长状态也较差。②生长曲线:接种后每24h更换培养液组的细胞生长增殖较快,比接种后每48h及72h更换培养液组达到的同样细胞数平均提前2～3d(P<0.05);接种后每48h及72h更换培养液组之间差异无显著性意义(P>0.05)。③间充质干细胞表面抗原特性:免疫细胞化学分析显示CD166呈阳性,vWF呈阴性。结论:胶原酶消化法体外分离获得的人脐静脉内皮及内皮下细胞数量高、活性佳。更换培养液的频度不同,细胞的增殖生长过程和形态变化时间不同,接种后每24h更换培养液更有利于间充质干细胞的增殖生长和纯化。     

Harm Reduction Behaviors Among Young Polysubstance Users at Raves

ABSTRACT. Background: Raves may be considered recreational settings in which drug use and health risks related to polydrug use are higher than in others. Harm reduction behaviors implemented by ravers are of particular relevance in reducing such risks. This study analyzes harm reduction behaviors and their relationship to raver polysubstance use patterns. Methods: Cross-sectional study of 248 ravers recruited at underground raves in Andalusia (Spain). A questionnaire was developed to collect information about their sociodemographics, drug use, and harm reduction behaviors. Results: The results show that ravers employ harm reduction behaviors for minimizing drug-related harm. Nevertheless, only a small minority of the participants frequently employed harm reduction behavior for polysubstance use as well. Ravers identified as high polysubstance users protected themselves significantly less than those identified as low polysubstance users. Conclusions: This study provides empirical information that may be useful for harm reduction intervention in a hidden and hard-to-reach population like rave attendees. The results point to the need to inform and increase harm reduction behavior specifically aimed at polysubstance use by ravers, especially among more frequent users. Future directions for research are also suggested.