精子形成过程中内质网的形态研究——超薄切片和冷冻蚀刻复型膜的电镜观察

本文报道了对超薄切片和冷冻蚀刻技术制备的小白鼠、大白鼠睾丸精小管样品的观察结果。在透射电镜下高尔基期精子细胞内质网较少;头帽期精子细胞内质网增多,有泡状、管状,并互相吻合形成交错的网络;高尔基期和头帽期精子细胞的内质网包裹高尔基复合体,与头帽的形成有关。顶体期精子细胞内质网最丰富,参与精子尾部轴丝、密纤维的形成。此期还可见到环形片层——放射体结构;成熟期精子细胞内质网退化、消失。由此可见内质网的变化与精子顶体、轴丝和密纤维的形成有密切关系。     

多媒体教材在永久性膀胱造瘘患者健康教育中的应用

目的：探讨多媒体教材在永久性膀胱造瘘患者及家属健康教育中的应用,寻找一种能让永久性膀胱造瘘患者及家属在较短时间内掌握造瘘护理技术、造瘘管更换技术和相关知识的健康教育方式。方法本研究以2009年1月-2012年12月在某院行膀胱造瘘术的60例患者为研究对象,用自制的健康需求调查表进行调查,将60例膀胱造瘘患者按照随机数字表法分为试验组和对照组,每组30例。试验组以多媒体方式进行理论教育后再进行一对一的指导,对照组采用传统的健康干预方式,即每次均来医院由医护人员边更换造瘘管边讲解造瘘相关护理知识的教育方式。比较两种方式的效果及并发症的发生率。结果试验组患者家属膀胱造瘘相关知识、造瘘口护理技术、造瘘管更换技术掌握率分别为100．00％,96．67％,90．00％,均优于对照组的36．67％,26．67％,10．00％,差异有统计学意义（χ2值分别为27．805,31．093,38．400;P＜0．05）;试验组患者出院后再次来院次数为（6．3±1．4）次,明显少于对照组的（36．2±6．6）次,差异有统计学意义（t＝22．224,P＜0．05）。两组患者的并发症发生率差异无统计学意义（ P＞0．05）。结论应用多媒体教材进行健康教育是一种能使患者及家属更快地适应膀胱造瘘,在较短的时间内掌握膀胱造瘘护理技术、造瘘管更换技术和相关知识的好方法,未增加并发症,值得推广。     

Pulmonary hypertensive effect of heparin and protamine interaction: evidence for thromboxane B2 release from the lung

The characteristic pulmonary hypertensive effect of the heparin and protamine interaction has been studied in the isolated pig lung preparation using sequential autologous blood perfusate and dextran perfusate. A significant (p less than 0.001) increase in pulmonary artery pressure at constant flow was seen in 10 of 14 dextran and 12 of 15 blood perfusions. The average increase for dextran was 112 percent and for blood, 109 percent. Antihistamines did not inhibit the response. However, this was abolished in all 11 animals treated with aspirin. In 11 intact swine, thromboxane B2 blood levels increased significantly (p less than 0.01) from 0.46 +/- 0.38 ng/dl to 2.97 +/- 1.5 ng/dl. Thus, pulmonary hypertension associated with protamine reversal of heparinization is associated with prostaglandin release from the lung, and this does not require mediation of platelets or leukocytes.     

过氧化体增殖物激活型受体γ和δ在高密度脂蛋白介导细胞胆固醇流出中的作用

为探讨过氧化体增殖物激活型受体γ和δ在高密度脂蛋白介导的细胞胆固醇流出中的作用。取新鲜抗凝血浆 ,用超速离心机进行密度梯度离心 ,收集密度为 1 .0 6 3～ 1 .2 1 0组分。U937细胞用 5 0～ 4 0 0nmol L反义过氧化体增殖物激活型受体γ和δ预处理细胞 1 2h。培养U937细胞与 0 .2 8mCi L [3H] 胆固醇乙醇液共孵育 2 4h ,15 0 0r min离心 1 0min ,收集细胞 ,PBS漂洗 2次 ,RPMI 1 6 4 0重悬细胞 ,加HDL继续培养 0～ 4 8h。液体闪烁计数仪测细胞相对放射活性。Westernblot检测过氧化体增殖物激活型受体γ和δ蛋白表达水平。不同浓度HDL处理后细胞胆固醇流出具有明显差异 ,呈剂量 -效应关系。用 1 0 0nmol L反义过氧化体增殖物激活型受体γ处理 2 4h后 ,HDL介导的细胞胆固醇流出减少 (4 5 78± 2 0 6 ) ,与对照组 (4 0 2 4± 385 )比较差别有显著性。过氧化体增殖物激活型受体γ激动剂ciglitizone预处理后 ,HDL介导的细胞胆固醇流出增加 ,用 0、2 5、5 0、1 0 0、2 0 0 μmol Lciglitizone处理的放射活性分别为 4 371± 2 4 3、386 9± 2 1 2、346 9± 2 0 9、31 5 6± 31 5和 30 2 0± 2 96。反义过氧化体增殖物激活型受体δ处理后 ,HDL介导的细胞胆固醇流出略有增加 ,处理浓度达 4 0 0nmol L时的放射活     

Maternal Zinc,Copper, and Selenium Intakes during Pregnancy and Congenital Heart Defects

The effects of zinc, copper, and selenium on human congenital heart defects (CHDs) remain unclear. This study aimed to investigate the associations of the maternal total, dietary, and supplemental intakes of zinc, copper, and selenium during pregnancy with CHDs. A hospital-based case-control study was performed, including 474 cases and 948 controls in Northwest China. Eligible participants waiting for delivery were interviewed to report their diets and characteristics in pregnancy. Mixed logistic regression was adopted to examine associations and interactions between maternal intakes and CHDs. Higher total intakes of zinc, selenium, zinc to copper ratio, and selenium to copper ratio during pregnancy were associated with lower risks of total CHDs and the subtypes, and the tests for trend were significant (all p < 0.05). The significantly inverse associations with CHDs were also observed for dietary intakes of zinc, selenium, zinc to copper ratio, selenium to copper ratio, and zinc and selenium supplements use during pregnancy and in the first trimester. Moreover, high zinc and high selenium, even with low or high copper, showed a significantly reduced risk of total CHDs. Efforts to promote zinc and selenium intakes during pregnancy need to be strengthened to reduce the incidence of CHDs in the Chinese population.     

Contribution of momilactones A and B to diabetes inhibitory potential of rice bran: Evidence from in vitro assays

This study was the first to detect the presence of the two compounds momilactone A (MA) and momilactone B (MB) in rice bran using liquid chromatography-electrospray ionization-mass spectrometry (LC-ESI-MS). By in vitro assays, both MA and MB exhibited potent inhibitory activities on pancreatic α-amylase and α-glucosidase which were significantly higher than γ-oryzanol, a well-known diabetes inhibitor. Remarkably, MA and MB indicated an effective inhibition on trypsin with the IC₅₀ values of 921.55 and 884.03 µg/mL, respectively. By high-performance liquid chromatography (HPLC), quantities of MA (6.65 µg/g dry weight) and MB (6.24 µg/g dry weight) in rice bran were determined. Findings of this study revealed the α-amylase, α-glucosidase and trypsin inhibitors MA and MB contributed an active role to the diabetes inhibitory potential of rice bran.     

Admission hyperlactatemia: causes, incidence, and impact on outcome of patients admitted in a general medical intensive care unit

Purpose

The aim of this study was to evaluate the causes, incidence, and impact on outcome of admission hyperlactatemia in patients admitted to a general medical intensive care unit (ICU).

Methods

A retrospective cohort study was done in an 8-bed general ICU of tertiary care hospital over 15 months. Data regarding patient demographics, probable cause of hyperlactatemia, presence of shock, need for organ support, and ICU outcome were recorded. Patients were divided into 2 groups based on admission lactate levels as follows: high lactate (>2 mmol/L) and normal lactate (<2 mmol/L). Patients were compared in terms of need for organ support and ICU mortality.

Results

Admission hyperlactatemia was present in 199 of 653 (30.47%) patients. Shock was the commonest cause, 53.3% patients, followed by respiratory and renal failure in 26 (13.1%) and 16 (8%) patients, respectively. Mean ± SD lactate levels in survivors and nonsurvivors were 1.64 ± 1.56 and 4.77 ± 4.72 mmol/L, respectively (P = .000). Receiver operating characteristic curve for lactate was 0.803 (95% confidence interval [CI], 0.753-0.853). Sensitivity and specificity of lactate (>2 mmol/L) to predict ICU mortality was 74.8% and 77.8%, respectively. Odds ratio for dying in patients with hyperlactatemia was 10.39 (95% CI, 6.378-16.925) with a relative risk of 1.538 (95% CI, 1.374-1.721). On subgroup analysis, in patients without hypotension too, ICU mortality was significantly increased in patients with hyperlactatemia (1.3% vs 6.45%, P = .009).

Conclusions

Admission hyperlactatemia is common in a general ICU and is associated with increased mortality, irrespective of presence of hypotension. Shock was the commonest cause for hyperlactatemia, followed by respiratory and renal failures.