Prevalence of asymptomatic left ventricular systolic dysfunction in hypertensive Nigerians: echocardiographic study of 832 subjects

Background

We sought to determine the prevalence of echocardiographically determined left ventricular systolic dysfunction in asymptomatic hypertensive subjects seen in Abeokuta, Nigeria.

Methods

Echocardiography was performed in 832 consecutive hypertensive subjects referred for cardiac evaluation over a three-year period.

Results

Data were obtained in 832 subjects (50.1% women) aged 56.0 ± 12.7 years (men 56.9 ± 13.3 years, women 55.0 ± 12.0 years, range 15–88). The prevalence of left ventricular systolic dysfunction (LVSD) was 18.1% in the study population (mild LVSD = 9.6%, moderate LVSD = 3.7% and severe LVSD = 4.8%). In a multivariate analysis, male gender, body mass index and LV mass were the predictors of LVSD.

Conclusion

Significant numbers of hypertensive subjects in this study had varying degrees of left ventricular systolic dysfunction. Early introduction of disease-modifying drugs in these patients, such as angiotensin converting enzyme inhibitors or angiotensin receptor blockers may retard or prevent the progression to overt heart failure.     

Population-based study of alpha- and gamma-tocopherol in plasma and adipose tissue as biomarkers of intake in Costa Rican adults

BACKGROUND: gamma-Tocopherol is the most abundant form of vitamin E in the US diet, but alpha-tocopherol concentrations are the highest in plasma and tissues. Although plasma and adipose tissue concentrations of alpha-tocopherol have been used as biomarkers of intake, the relation between gamma-tocopherol intake and concentrations in plasma and adipose tissue is unknown. OBJECTIVE: Our goal was to investigate in a randomly selected population from Costa Rica whether plasma or adipose tissue concentrations of alpha- and gamma-tocopherol are suitable biomarkers of intake. DESIGN: A total of 361 men (x +/- SD age: 55 +/- 11 y) and 121 women (aged 59 +/- 10 y) completed a 135-item food-frequency questionnaire and provided a fasting blood sample and adipose tissue biopsy sample. RESULTS: Dietary gamma-tocopherol correlated with adipose tissue (r = 0.37, P < 0.001) and plasma (r = 0.42, P < 0.001) concentrations, regardless of supplement use. Dietary alpha-tocopherol correlated poorly with adipose tissue (r = 0.15, P < 0.01) and plasma (r = 0.16, P < 0.001) concentrations, and these correlations were even lower when users of vitamin supplements (n = 24) were excluded (adipose tissue: r = 0.10, P < 0.05; plasma: r = 0.09, P < 0.05). Compared with subjects who reported palm shortening (36%) as the major type of fat used for cooking, subjects using soybean oil (52%) had higher amounts of both alpha- and gamma-tocopherol in their diets. However, only gamma-tocopherol concentrations were higher in the plasma and adipose tissue of soybean oil users. CONCLUSIONS: Plasma and adipose tissue concentrations of gamma-tocopherol are equally good biomarkers of intake. The weak associations between alpha-tocopherol intake and plasma or adipose tissue concentrations suggest that these biomarkers are influenced more by factors other than alpha-tocopherol intake.     

中药葛根及其同属植物的资源利用和评价

对我国葛属（ＰｕｅｒａｒｉａＤＣ，）９种和１变种植物进行了调查研究，认为目前国内市售中药葛根的主流品种为野葛Ｐ，ｌｏｂａｔａ（Ｗｉｌｌｄ．）Ｏｈｗｉ和粉葛Ｐ．ｔｈｏｍｓｏｎｉｉ）Ｂｅｎｔｈ．。野葛在我国大部份省区都有分布，资源最为丰富；粉葛在广西载培历史悠久；其他种主要分布在西南地区，并有少数种在当地作中药葛根用。从成分分析结果看，野葛的葛根素（ｐｕｅｒａｒｉｎ）及总黄酮含量显著高于本属其它植物，粉葛次之。除野葛和粉葛外其他种均不宜作葛根药用。峨嵋葛Ｐ．ｏｍｅｉｅｎｓｉｓＷａｎｇｅｔＴａｎｇ是个有争议的种，我们比较了化学成分的含量，其结果与粉葛相近，而与山葛藤有所区别，有待进一步研究。     

p14ARF expression in invasive breast cancers and ductal carcinoma in situ – relationships to p53 and Hdm2

Introduction  

p14^ARF stabilises nuclear p53, with a variable expression of p14^ARF mRNA in breast cancers. In vitro, nuclear p14^ARF binds Hdm2 to block Hdm2-dependent nucleocytoplasmic shuttling of p53, which is required before cytoplasmic degradation of p53. p14^ARF is negatively regulated by p53 and through p53-independent pathways. No studies have yet examined levels of p14^ARF protein expression in breast cancer and their relationship to Hdm2/p53 immunoreactivity or subcellular localisation. Previously, immunohistochemical expression of cytoplasmic p14^ARF, p53 and Hdm2 has been described. HER-2 (c-erbB2/neu) predicts prognosis and interacts with the p14^ARF/Hdm2 pathway to inactivate p14^ARF and to influence Hdm2 activity and localisation. This study examined p14^ARF and p53/Hdm2 expression and subcellular localisation by using immunohistochemistry in a series of invasive ductal breast cancers (IDCs) with concomitant ductal carcinoma in situ (DCIS), to evaluate whether findings in vitro were related to clinicopathological parameters such as HER-2 and their effect on patient outcome.     

Response of plasma histaminase activity to heparin in normal subjects and in patients with small cell carcinoma of the lung.

Plasma histaminase (PH) activity only partially reflected the consistently high activity of histaminase in tumor tissue of patients with small cell carcinoma of the lung (SCC). To determine whether heparin might release histaminase from tumor tissue into the circulation as it does from some normal tissues, we studied the response of PH activity to small doses of heparin in 41 patients with SCC and in 57 normal subjects. In patients with SCC, the initial mean PH activity (2.0 U/m) was not different from that in normal subjects (1.7 U/ml). After heparin administration, the mean PH activity was no different between the 2 groups (patients with SCC, 3.1 U/ml; normal subjects, 3.5 U/ml). In both groups, the higher the initial PH activity, the greater the magnitude of the PH activity response to heparin. This relationship was linear (normal subjects, r = 0.88; patients with SCC, r = 0.91). However, in patients with SCC, the increase in post-heparin PH activity, as related to the basal levels, was significantly less than that in normal subjects (P less than 0.001 by analysis of covariance). The data suggested that heparin did not affect the release of histaminase from tumor tissue into plasma to the same degree as it promoted the enzyme's entry from normal tissue sources. The differences between the groups may enable us to differentiate between selected patients with SCC and normal subjects with borderline high PH activity values.     

Coffee consumption and risk of type 2 diabetes and heart disease

Coffee seems to have distinct acute and long-term effects on health, which can be modified by genetic background. Coffee consumption is potentially protective against the development of type 2 diabetes, but given the lack of a solid biological basis for this association, and the possible adverse cardiovascular effects of coffee, recommendations for optimal coffee intake are difficult to establish.     

快速成型骨组织工程支架的结构及力学仿生性能特征

目的:利用显微CT的成像技术及材料力学测试,观察多孔双相磷酸钙陶瓷支架的三维结构和力学仿生性能特征。方法:实验于2004-06/2005-12在清华大学新型陶瓷与精细工艺国家重点实验室、香港中文大学威尔士亲王医院骨与关节肌肉研究室和解放军总医院骨科研究所完成。利用三维凝胶叠层成型技术和发泡法复合的方法,制备仿骨多孔双相磷酸钙陶瓷支架,经显微CT扫描得到分辨率为20μm的断层图像,并按骨形态计量方法计算三维计量参数,并与急性脑死亡年轻人股骨头(由解放军总医院骨组织库提供,已签署捐献同意书)标本负重区松质骨样本的三维参数进行统计比较。最后对双相磷酸钙陶瓷支架两个互相垂直方向和松质骨样本的长轴方向进行压缩强度试验,计算压缩强度和弹性模量,并进行统计分析。结果:①双相磷酸钙陶瓷支架的小梁平均宽度和间距低于松质骨小梁(P<0.05);支架的小梁数目和各项异性程度高于松质骨样本(P<0.05);说明支架小梁在排列上呈现更为明显的各向异性特征。②双相磷酸钙陶瓷支架的体积分数、表面积体积比及结构模型指数与松质骨样本相比差异无显著性(P>0.05),两组样本均呈明显的板层结构。③力学测试结果显示双相磷酸钙陶瓷支架材料长轴方向的强度和弹性模量高于垂直方向(P<0.05),说明支架材料具有明显的方向性。长轴方向的强度低于正常松质骨样本,但弹性模量仅比松质骨样本弹性模量高20%(P<0.05)。结论:支架材料在空隙率和表面积方面具有很好的仿生性,利于细胞的黏附和长入。同时具有明显的方向性,提高了其在排列方向上的强度。弹性模量接近股骨头松质骨,具有较好的应力顺应性。     

大鼠骨髓间充质干细胞体外分离、纯化与培养适宜条件的筛选

目的:为获得大量、高纯度的骨髓间充质干细胞,筛选体外分离、纯化和培养的适宜条件。方法:实验于2006-08/2007-07在解放军兰州军区兰州总医院进行。①实验材料:2月龄SD大鼠,雄性,体质量(100±20)g,由解放军兰州军区兰州总医院实验动物科提供。②实验方法:分别采用全骨髓法(贴壁筛选法)和密度梯度离心法分离和纯化大鼠骨髓间充质干细胞。将采用密度梯度离心法获得的单个核细胞按1×107,1×108,1.5×108,2×108,1×109,2×109L-1的接种密度分别分成1～6组,接种在24孔板内,每组接种6孔。比较细胞出现伸展时间、原代培养时间。于细胞接种后第1,2,3,4,5,6天进行首次换液。将换下的部分细胞置于新的培养皿中进行培养,至少培养3d,观察是否还有新的贴壁细胞出现,以确定首次换液时间。观察体积分数为0.10,0.12,0.15,0.18,0.20血清对原代及传代后细胞生长的影响,比较不同浓度血清中细胞数量、集落形成率。集落形成率=集落数目/接种细胞数目×100%。采用流式细胞仪检测骨髓间充质干细胞细胞周期。选取第5代扩增的骨髓间充质干细胞,接近完全融合后进行成骨和成脂肪诱导培养。诱导剂分别为:10nmol/L地塞米松、0.05nmol/L抗坏血酸及10nmol/Lβ-甘油磷酸钠;1μmol/L地塞米松、0.5mmol/LIBMX、0.01mmol/L人胰岛素、0.01mmol/L吲哚美辛。并设未加诱导剂培养液培养的骨髓间充质干细胞对照。③实验评估:采用碱粒酶测定成骨诱导后细胞,采用油红O染色鉴定成脂肪诱导后细胞。结果:①细胞出现伸展时间、原代培养时间:密度梯度离心法培养细胞出现伸展时间与全骨髓法相比,差异无显著性意义。密度梯度离心法原代培养时间较全骨髓法长[(9.41±1.11),(14.73±2.86)d,P<0.05]。②不同接种密度对密度梯度离心法所获细胞生长影响:1×109L-1组细胞出现伸展时间及原代培养细胞融合时间较早。1×107L-1组培养20d内不能传代。③首次换液时间对细胞生长的影响:第5天开始在换下的液体中,很少有再贴壁的细胞出现。因此首次换液时间应为第5天。④不同体积分数血清对细胞生长的影响:在其他条件相同的前提下,骨髓间充质干细胞在含体积分数为0.12胎牛血清中细胞集落形成率最高。⑤成骨及成脂诱导:成骨诱导的骨髓间充质干细胞经碱粒酶测定,结果钙化结节呈蓝色。成脂诱导的骨髓间充质干细胞经油红O染色,苏木精-伊红复染后胞内脂滴呈桔红色,核呈蓝色。结论:采用密度梯度离心法分离纯化的骨髓间充质干细胞以1×109L-1密度接种,在含体积分数为0.12胎牛血清的MEM培养基中培养,生长状况良好,增殖速度快。