Selective elution of HLA antigens and beta 2-microglobulin from human platelets by chloroquine diphosphate

To determine whether chloroquine can specifically elute HLA antigens and beta 2-microglobulin (beta 2-M) from the platelet surface, quantitative immunofluorescence flow cytometry and monoclonal antibodies were used to show that HLA antigens and beta 2-M were proportionally eluted from the platelet surface without affecting the membrane glycoproteins IIb and IIIa. Second, an autoradiogram of electrophoresed I125-labeled platelets showed that only beta 2-M but not other I125-labeled membrane proteins could be eluted. Although HLA antigens were poorly labeled by I125 and could not be detected on the autoradiogram, the eluted HLA antigens could be detected by anti-HLA monoclonal antibody and immunoblotting techniques. No loss of plasma membrane integrity was observed by transmission electron microscopy after chloroquine treatment of platelets. The results indicate that chloroquine selectively elutes HLA antigens and their noncovalently associated beta 2-M without affecting other integral platelet membrane proteins.     

低血糖指数膳食改善超重老年糖尿病患者氧化应激水平

目的:观察低血糖指数的膳食对2型糖尿病患者氧化应激状态的影响。方法:2004-10/11在上海市静安区二个社区卫生服务中心招募受试者,经医生明确诊断为2型糖尿病、病程超过6个月,体质量指数≥24kg/m2的老年糖尿病志愿者43名,受试者对试验知情同意。采用随机交叉试验随机分配至低血糖指数饮食组和高血糖指数饮食组,每种膳食分别连续使用4周,间隔洗脱期4周,比较试验前后患者超氧化物歧化酶、脂质过氧化产物丙二醛和谷胱甘肽过氧化物酶含量的变化。结果:受试者依从性好,除1人因试验期间发现肿瘤而退出试验,42名志愿者按设计要求完成试验。膳食干预后低血糖指数饮食组和高血糖指数饮食组的超氧化物歧化酶活力分别升高了15.68%和21.33%,丙二醛水平分别下降23.94%和21.55%,谷胱甘肽过氧化物酶活力分别升高了15.74%和17.09%;干预后低血糖指数饮食组丙二醛下降水平与高血糖指数饮食组比较差异有显著性意义(P<0.05),而超氧化物歧化酶和谷胱甘肽过氧化物酶活性两组间差异无显著性意义(P>0.05)。结论:在控制总能量的基础上给予平衡膳食能够改善其氧化应激水平,采用低血糖指数食物有助于氧化应激水平的改善。     

Depressive symptoms,physical symptoms,and health-related quality of life among older adults with HIV

Quality of Life Research - In the United States, approximately 45% of persons living with HIV (PLHIV) are ≥ 50&nbsp;years of age. Many older PLHIV have multi-morbidities that...     

Correlation between Rotator Cuff Tears and Repeated Subacromial Steroid Injections: A Case-Controlled Study

INTRODUCTION

Concern exists regarding potential damage to the rotator cuff from repeated corticosteroid injections into the subacromial space.

PATIENTS AND METHODS

In this retrospective, case-controlled study, 230 consecutive patients presenting to three orthopaedic units with subacromial impingement and investigated as an end-point with magnetic resonance imaging (MRI) of the shoulder were divided into groups having received less than three or three or more subacromial injections of corticosteroids.

RESULTS

With no significant difference in age and sex distribution, analysis by MRI showed no significant difference between the two groups in the incidence of rotator cuff tear (P < 1.0).

CONCLUSIONS

This suggests that corticosteroid use in patients with subacromial impingement should not be considered a causative factor in rotator cuff tears.     

A Social Cognitive Model of Health for HIV-Positive Adults Receiving Care in India

In-depth interviews were conducted with 50 HIV-positive adults (23 women, 27 men) with access to care at a non-governmental organization in Chennai, India to gain a broad understanding of how they managed their HIV infection. Using a Social Cognitive Model of Health, we identified factors within the model's three domains--Personal, Environmental, and Behavioral--that are applicable to this socio-cultural context. The Personal domain's factors were a positive self-concept, family-focused goals, and treatment optimism; the Environmental domain comprised family-based support, treatment availability, access and quality, and HIV stigma and discrimination; and the Behavior domain's factors were medication adherence and health habits, sexual behavior, and social relationships and emotional well-being. Significant differences for many of the factors within the three domains were observed across married men and women, widowed women, unmarried men, and female sex workers. Implications for an enhanced intervention for HIV-infected individuals in similar treatment settings are discussed.     

Psychosocial Predictors of Sexual HIV Transmission Risk Behavior among HIV-Positive Adults with a Sexual Abuse History in Childhood

Childhood sexual abuse (CSA) is associated with HIV sexual risk behavior. Although many psychosocial correlates of sexual risk among HIV-positive persons have been identified, studies predicting continued risk among HIV-positive adults with histories of CSA are limited. This cross-sectional study identified variables predictive of sexual transmission risk behavior among an ethnically diverse sample of 256 HIV-positive adults (women and men who have sex with men; MSM) with CSA histories. Participants were assessed for trauma symptoms, shame related to HIV and sexual trauma, substance use, coping style, and sexual risk behavior. Logistic regression analyses were conducted to identify variables predictive of unprotected sexual behavior in the past 4 months. Unprotected sex was significantly associated with substance use and trauma-related behavioral difficulties among women and men, and less spiritual coping among men. Unprotected sex with HIV negative or serostatus unknown partners was significantly associated with greater trauma-related behavioral difficulties, more HIV-related shame, and fewer active coping strategies. Thus, trauma symptoms, shame, coping style, and substance use were significantly associated with sexual risk behavior among HIV-positive adults with histories of CSA, with models of prediction differing by gender and partner serostatus. HIV prevention intervention for persons with HIV and CSA histories should address trauma-related behavioral difficulties and enhance coping skills to reduce sexual transmission risk behavior.     

A population-based case-control study of Selective Serotonin Reuptake Inhibitors (SSRIs) and breast cancer: The impact of duration of use, cumulative dose and latency

Background  

Selective serotonin reuptake inhibitors (SSRIs), a popular class of antidepressants, may increase breast cancer risk by stimulating the secretion of prolactin, a potential tumour promoter. We evaluated the effects of duration of SSRI use, cumulative dose, and latency on the risk of breast cancer by conducting a population-based case-control study utilizing Saskatchewan health databases.     

Interleukin-3 treatment of rhesus monkeys leads to increased production of histamine-releasing cells that express interleukin-3 receptors at high levels

To understand the hematopoietic and nonhematopoietic responses to interleukin-3 (IL-3), expression of cell-surface IL-3 receptors (IL-3R) was examined on bone marrow (BM) cells and peripheral blood (PB) cells of rhesus monkeys during the course of in vivo IL-3 treatment. Whereas IL-3R expression is low in untreated monkeys, IL-3 administration led to a gradual increase in both low- and high-affinity binding sites for IL-3. This increase reflected the total number of cells expressing IL- 3Rs, as detected by flow cytometry using biotinylated IL-3. Most of these IL-3R+ cells in both BM and PB could be characterized as basophilic granulocytes that contained high levels of histamine. In contrast to the effect on these differentiated cells, IL-3 administration did not significantly alter the low level IL-3R expression on immature, CD34+ cells. Further flow cytometric analysis using biotinylated growth factors showed that the IL-3R+ basophils also expressed receptors for granulocyte-macrophage colony-stimulating factor (GM-CSF), but not for IL-6 or Kit ligand. These findings indicated that the IL-3R+ cells included neither monocytes, which express GM-CSFRs and IL-6Rs abundantly, nor mast cells, which express c- kit. By combining flow cytometric and Scatchard data, it was calculated that the basophils contain as many as 1 to 2 x 10(3) high-affinity IL- 3Rs and 15 to 30 x 10(3) low-affinity sites. The finding that in vivo IL-3 treatment leads to the production of large numbers of cells that express high levels of IL-3R and are capable of producing histamine provides an explanation for the often severe allergic reactions that occur during prolonged IL-3 administration. It also indicates that IL- 3, in addition to its direct effects on hematopoietic cells, may also stimulate hematopoiesis through the release of secondary mediators such as histamine by IL-3-responsive mature cells.