自身免疫与动脉粥样硬化的发生发展

在动脉粥样硬化的发生发展过程中,自身免疫具有重要作用,本文就近年有关动脉粥样硬化的免疫机制的研究进展作一简要综述.     

Cement and Concrete Nanoscience and Nanotechnology

Concrete science is a multidisciplinary area of research where nanotechnology potentially offers the opportunity to enhance the understanding of concrete behavior, to engineer its properties and to lower production and ecological cost of construction materials. Recent work at the National Research Council Canada in the area of concrete materials research has shown the potential of improving concrete properties by modifying the structure of cement hydrates, addition of nanoparticles and nanotubes and controlling the delivery of admixtures. This article will focus on a review of these innovative achievements.     

慢性饮酒、吸烟与骨质疏松的相关性研究

目的 探讨长期大量慢性饮酒、吸烟等不良生活方式与骨质疏松的关系.方法 以乏力、腰背痛、双下肢酸困为主诉,且有长期大量慢性饮酒史、吸烟史,无其他慢性疾病史的年轻男性患者45例为观察对象,测定其血钙(Ca)、血磷(P)和血肌酐(Cr)、尿素氮(BUN)、血糖(Glu)、天门冬酸氨基转移酶(AST)、丙氨酸基转移酶(ALT)、血清碱性磷酸酶(ALP)、甲状腺功能、全段甲状旁腺激素(iPTH)、1,25-二羟维生素D3[1,25-(OH) 2D3]、双能X线骨密度仪测定腰椎L1-4及左侧股骨近段(包括颈、股骨颈上部、大粗隆)骨密度(BMD),分析饮酒、吸烟对骨量的影响.以感冒发热就诊、年龄相当、无饮酒、吸烟史及慢性疾病史的45例男性为对照组.结果 观察组1,25(OH)2D3水平均降低,血钙水平偏低,血磷正常,碱性磷酸酶呈不同程度地升高,骨密度T值提示观察组27例骨质疏松,12例骨量减少,6例正常骨量;而对照组仅有6例为骨量减少,1例骨质疏松,38例为正常骨量,两组比较差异有统计学意义(P＜0.05).结论 长期慢性大量饮酒吸烟影响骨量,甚至易导致骨质疏松.     

Medical and Psychology Students' Knowledge and Attitudes Regarding Aging and Sexuality

The current study surveys medical and doctoral psychology students (N = 100) from an urban northeastern university regarding knowledge and attitudes toward elderly sexuality and aging using the Facts on Aging Quiz, the Aging Sexuality Knowledge and Attitudes Scale, and measures of interest in gerontology, academic/clinical exposure to aging and sexuality, and contact with elders. The current study found that psychology students demonstrated greater aging knowledge than medical students; however, both groups showed gaps in knowledge about sexuality. Married students had greater academic/clinical exposure and greater knowledge about aging but less permissive attitudes toward elderly sexuality. Generally, knowledge about aging was the strongest correlate of knowledge about sexuality. Level of knowledge about sexuality was not associated with attitudes. Attitudes toward sexuality and aging may be more strongly tied to demographic variables reflective of religious beliefs or adherence to sociocultural norms.     

Immune and serologic profiles of HIV-infected and noninfected hemophilic children and adolescents

Objectives: To assess relationships among the effects of HIV on hemophilic children and adolescents' immunologic parameters and vaccine-related serology. Methods: We analyzed data from extensive baseline immunologic evaluations of 207 HIV antibody-positive (HIV+) and 126 HIV antibody-negative (HIV?) hemophilic children and adolescents. Results: HIV+ and HIV- participants differed significantly in T-lymphocyte subpopulation numbers, immunoglobulin levels, and seroprevalence rates for diphtheria toxoid, measles, and mumps antigens. IgG levels, IgM levels, and serologic titers to vaccine antigens showed little correlation with T-cell parameters. Proportionately more HIV+ participants were nonreactive to each and all of a panel of 7 skin test antigens (71 % vs 28% anerglc, RR 2.6). The odds of anergy increased 1.6 times for every decline of 200 CD4 ± cells/μTl. Conclusions: HIV had significant, largely independent T- and B-lymphocyte effects on this pediatric cohort. © 1994 Wiley-Liss, Inc.     

ADH and ALDH Polymorphisms and Alcohol Dependence in Mexican and Native Americans

Background: Ethanol is primarily metabolized in the liver by two rate-limiting reactions: conversion of ethanol to acetaldehyde by alcohol dehydrogenase (ADH) and subsequent conversion of acetaldehyde to acetate by aldehyde dehydrogenase (ALDH). ADH and ALDH exist in multiple isozymes that differ in their kinetic properties. Notably, polymorphisms within the genes that encode for these isozymes vary in their allele frequencies between ethnic groups, and thus, they have been considered as candidate genes that may differentially influence risk for the development of alcohol dependence across ethnic groups. Objectives and methods: Associations between alcohol dependence and polymorphisms in ADH1B, ADH1C, and ALDH2 were compared in a community sample of Native Americans (n 791) living on reservations and Mexican Americans (n 391) living within the same county. Results: Two Mexican Americans and no Native Americans possessed one ALDH2*2 allele. Presence of at least one ADH1B*2 allele was found in 7% of the Native Americans and 13% of the Mexican Americans, but was only associated with protection against alcohol dependence in the Mexican Americans. Presence of at least one ADH1B*3 allele was found in 4% of the Native Americans and 2% of the Mexican Americans, but was associated with protection against alcohol dependence only in the Native Americans. No associations between alcohol dependence and polymorphisms in ADH1C were found. Conclusions and Scientific Significance: Polymorphisms in ADH1B are protective against alcoholism in these two populations; however, these findings do not explain the high prevalence of alcoholism in these populations.     

Leptin and cellular and innate immunity in abstinent alcoholics and controls

BACKGROUND: Basic studies indicate that in vitro and in vivo doses of leptin modulate cellular immune responses. Given evidence that concentrations of leptin are altered in alcoholics who also show immune abnormalities, this study examined the relationships between circulating levels of leptin and markers of cellular and innate immunity. METHODS: Circulating levels of leptin, natural killer cell (NK) activity, interleukin-2 (IL-2)-stimulated NK activity, and concanavalin A-stimulated production of IL-2, IL-6, IL-10, and IL-12 were compared between abstinent DSM-IV alcohol-dependent men (n = 27) and age- and gender-matched controls (n = 34). RESULTS: As compared with controls, alcoholics showed lower NK activity (p < 0.01) and a trend for lower levels of leptin (p = 0.055). In the total sample, leptin predicted NK activity (beta = 0.33; p < 0.05) after controlling for the confounding influence of body mass index, alcohol intake, and smoking. Leptin was not correlated with any of the cytokine measures. To examine whether the effects of leptin were mediated by its direct action on NK, additional studies examined in vitro effects of leptin on NK activity in healthy volunteers (n = 10); leptin doses (0.1, 1, and 10 nM) yielded levels of NK activity comparable to those with media alone. CONCLUSIONS: These data show that circulating levels of leptin are associated with NK activity in humans and suggest that abnormal in vivo concentrations of leptin may contribute to the declines of NK activity in alcoholics who are at risk for infectious diseases.