胆红素对神经突触膜Na^＋,K^＋—ATP酶影响的实验研究

为了研究胆红素的神经毒性作用，对５９只出生２天的ＳＤ大白鼠分别予以腹腔注射不同剂量胆红素制造高胆红素血症动物模型，不连续密度梯度法分离提取脑神经元突触膜，测定Ｎａ＋，Ｋ＋－ＡＴＰ酶活力。结果：随着血清胆红素浓度的逐渐增加，脑组织中胆红素沉积量也逐渐增加，神经元突触膜Ｎａ＋，Ｋ＋－ＡＴＰ酶活力逐渐降低，Ｎａ＋，Ｋ＋－ＡＴＰ酶活力与脑组织中沉积的胆红素量呈负相关（ｒ＝－０．３４，Ｐ＜０．０１）。提示：胆红素对Ｎａ＋，Ｋ＋－ＡＴＰ酶具有抑制作用。     

特发性高钙尿症患儿红细胞膜钙泵活性的测定

目的探讨小儿特发性高钙尿症红细胞膜钙系活性变化特点及其意义。方法特发性高钙尿症３８例，２０名健康儿童为对照组。以红细胞膜（Ｃａ＋＋－Ｍｇ＋＋）－ＡＴＰ酶和（Ｎａ＋－Ｋ＋）－ＡＴＰ酶同步测定法检测红细胞膜钙泵活性，并对结果进行统计学分析。结果肠吸收型特发性高钙尿症红细胞膜钙泵活性明显高于对照组（Ｐ＜０．０１），而肾脏漏出型却明显低于正常对照组（Ｐ＜０．０５）。结论特发性高钙尿症患儿存在细胞膜钙泵活性异常，此可能与其发病机制密切相关。     

磷酸受纳蛋白的研究进展

磷酸受纳蛋白（PLB）是心脏肌浆网钙泵的主要调节因子，后者在心肌细胞胞浆钙浓度的调节中发挥主要作用，心肌细胞胞浆钙浓度是心肌兴奋－收缩偶联的关键因子，因此，PLB在维持细胞内钙稳态和正常的心肌舒缩功能上有着重要的作用，近年来有关PLB的心脏病中作用的研究逐渐增多。本文就PLB的结构、基因表达和对肌浆网钙泵的调节作用及其在心脏病中的意义作一综述。     

大鼠急性感染性脑水肿神经元突触体钙离子浓度与线粒体酶活性的研究

目的探讨感染性脑水肿神经细胞钙通道变化,神经元细胞内游离钙离子浓度（［Ｃａ２＋］ｉ）和Ｃａ２＋ＡＴＰ酶活性变化及其之间的关系。方法采用急性感染性脑水肿模型,测定神经元突触体胞浆内［Ｃａ２＋］ｉ和线粒体Ｃａ２＋ＡＴＰ酶活性变化,并选用Ｃａ２＋通道阻滞剂尼莫地平进行治疗,观察其对突触体［Ｃａ２＋］ｉ和线粒体Ｃａ２＋ＡＴＰ酶活性的影响。结果在注菌后３０分钟４、２４小时感染性脑水肿突触体［Ｃａ２＋］ｉ分别为３０５±２７、３５２±２１、４１３±４８ｎｍｏｌ／Ｌ,线粒体Ｃａ２＋ＡＴＰ酶活性分别为０５２±０１２、０３５±００８、０２４±０１２μｍｏｌ／（ｇ·ｈ）;电镜检查结果亦表明,菌液组突触体和线粒体明显肿胀,内有空泡形成。应用尼莫地平治疗后［Ｃａ２＋］ｉ明显下降,而Ｃａ２＋ＡＴＰ酶活性明显恢复,脑水肿减轻。结论感染性脑水肿神经细胞钙离子通道开放,细胞内Ｃａ２＋超载,突触体［Ｃａ２＋］ｉ与线粒体Ｃａ２＋ＡＴＰ酶活性变化呈负相关关系;尼莫地平通过降低突触体胞浆中［Ｃａ２＋］ｉ和恢复线粒体Ｃａ２＋ＡＴＰ酶活性,从而减轻脑水肿     

原发性高血压患儿红细胞膜三磷酸腺苷酶活性及血液黏度改变的意义

目的 探讨原发性高血压患儿红细胞膜Na 、K -ATP酶、Ca2 、Mg2 -ATP酶活性及血液黏度改变的意义.方法 对本院2004年11-12月坚持随访的50例原发性高血压患儿进行红细胞膜Na 、K -ATP酶、Ca2 、Mg2 -ATP酶活性(比色法)及血液黏度测定,并与30例健康儿童作对照,采用SPSS 12.0软件进行t检验及直线相关分析.结果 原发性高血压组患儿红细胞膜Na 、K -ATP酶、Ca2 、Mg2 -ATP酶活性[(6.12±1.30) μmolpi/(gHb·h)和(4.59±1.40) μmolpi/(gHb·h)]较健康对照组[(7.46±1.30) μmolpi/(gHb·h)和(5.81±1.20) μmolpi/(gHb·h)]显著降低(Pa＜0.01);血液黏度较健康对照组显著升高(Pa＜0.01).原发性高血压组Na 、K -ATP酶、Ca2 、Mg2 -ATP酶活性与血液黏度均呈负相关(P＜0.05,0.01).结论 Na 、K -ATP酶、Ca2 、Mg2 -ATP酶活性降低及血液黏度升高可能在儿童高血压发病机制中起重要作用.     

肥胖儿童红细胞钙镁水平及ATP酶活性与高血压关系的探讨

目的     

肺炎患儿红细胞离子浓度变化及其与CK、CK-MB关系的研究

目的　探讨肺炎患儿不同程度缺氧时钙泵、钠泵活性和红细胞离子浓度的变化 ,及其与CK、CK MB的关系。方法　对 6 1例 5岁以下肺炎患儿同步测定血气分析 ,红细胞钙泵 (Ca2 + Mg2 + ) ATP酶和钠泵 (Na+ K+ ) ATP酶活性 ,红细胞内钙 (EryCa2 + )、镁 (EryMg2 + )和血浆钙 (B Ca2 + )、镁 (B Mg2 + )、钠 (B Na+ )、钾 (B K+ )和游离钙 (B iCa2 + )浓度 ,及血清CK、CK MB ;并与 16例健康儿童比较。肺炎组按照动脉血氧分压 (PaO2 )分为轻度、中度和重度缺氧组。结果　 (1)随着肺炎患儿缺氧程度加重 ,(Ca2 + Mg2 + ) ATP酶和 (Na+ K+ ) ATP酶活性下降 ,B Na+ 、B Ca2 + 、B iCa2 + 和EryMg2 + 降低 ,B K+和EryCa2 + 升高 ,尤以重度缺氧组为甚。 (2 )重度缺氧组CK MB活性升高和异常率分别升高到 (99±6 8)U/L和 75 % ,与轻、中度缺氧组比较差异有显著性 (P <0 0 5 )。 (3) (Ca2 + Mg2 + ) ATP酶、(Na+ K+ ) ATP酶活性、B Na+ 及B iCa2 + 与CK MB活性呈负相关 (r分别为 - 0 4 4 1、- 0 30 5、 - 0 4 34、- 0 75 3,P均 <0 0 5 )。结论　缺氧所导致离子稳态失调是引起肺炎患儿心肌损伤的一个原因。钙泵和钠泵活性随缺氧程度加重而下降 ,尤其是钙泵。早期纠正缺氧可能阻止其活性的下降及其后继的     

室间隔缺损并心力衰竭时红细胞钙离子代谢变化

目的探讨室间隔缺损（VSD）合并心力衰竭（心衰）患儿红细胞钙离子的代谢变化。方法正常对照组12人．VSD无心衰组10人，VSD合并心衰组21人。测定其红细胞内Ca2＋浓度（[Ca2＋]）、45Ca跨膜流动及膜ATPase活性。结果VSD合并心衰时红细胞内[Ca2＋]及45Ca净摄取较对照组显著增加，45Ca单向性内流无变化，而膜Ca2＋－Mg2＋ATPase和Na＋－K＋ATPase活性则明显下降。结论心衰时细胞内[Ca2＋]增高不是细胞膜对Ca2＋的通透性改变所致，而与细胞排Ca2＋能力下降有关；VSD并心衰患儿细胞内Ca2＋代谢变化是由于VSD导致血液动力学改变后，引起机体代谢变化，而随之发生变化的。     

有心肌梗塞家族史儿童血清脂蛋白（a）的研究

为探讨有心肌梗塞家族史的少年儿童血脂的改变，特别是脂蛋白（ａ）的改变，采用单克隆抗体酶联免疫吸附实验，对３３例有心肌梗塞家族史的少年儿童测定其脂蛋白（ａ）［Ｌｐ（ａ）］。结果：血清Ｌｐ（ａ）＞３００ｍｇ／Ｌ：心肌梗塞家族史阳性的３３例中有１６例（４８％），而对照组３３例中只有５例（１５％）（χ２＝８．５４０，Ｐ＜０．０５）；有心肌梗塞家族史儿童的血清Ｌｐ（ａ）含量明显高于对照组。提示：对有心肌梗塞家族史的后代，应适时检测Ｌｐ（ａ），及早施行干预措施，以达到预防的目的。     

Lipoprotein (a) levels in children and young adults: the influence of physical activity. The Cardiovascular Risk in Young Finns Study

A high lipoprotein(a) (Lp(a)) level is an independent and predominantly genetically determined risk factor for coronary heart disease and other vascular diseases. We studied the levels of Lp(a) and the influence of physical activity on Lp(a) in the young Finnish population.The study cohort comprised children and young adults aged 9, 12, 15, 18, 21 and 24 years ( n = 2464) participating in a large multicenter follow-up study of cardiovascular risk factors in children and young adults. Data were available on physical activity, anthropometric variables, serum Lp(a), insulin and lipid levels. A physical activity index was calculated based on several physical activity variables. Lp(a) was determined by radioimmunoassay with a detection threshold of 3 mg/dl. Differences were assessed with non-parametric statistical analyses. The observed range of Lp(a) was from < 3 to 90.8 mg/dl. The distribution of Lp(a) was highly skewed as 88% of the population (89% males and 87% females) had Lp(a) concentrations less than 25 mg/dl. A total of 35% of the subjects had Lp(a) levels less than 3 mg/ dl. There were no significant differences in Lp(a) levels with respect to age or gender. The serum concentration of Lp(a) was statistically significantly correlated with the level of physical activity. Other behavioral variables studied did not have a significant contribution to the variability of Lp(a) levels. These results demonstrate that levels of Lp(a) are not related to age, gender or many of the known coronary heart disease risk factors. However, physical activity is associated with favorable Lp(a) levels, as high levels of Lp(a) (> 25 mg/dl) were less frequent in the physically most active subjects.     

肺血流量对血浆内皮素—1水平影响的研究

为研究肺血流量对血浆ＥＴ－１水平的影响以帮助阐明肺高压的发病机制,本实验将先心患儿分为无高肺血流伴肺动脉压力正常的对照组及高肺血流组,高肺血流组再分为伴肺高压组及肺动脉压力正常组。     

Additive effect of eosinophilia and atopy on exhaled nitric oxide levels in children with or without a history of respiratory symptoms

Although atopy and blood eosinophilia both influence exhaled nitric oxide (eNO) measurements, no study has quantified their single or combined effect. We assessed the combined effect of atopy and blood eosinophilia on eNO in unselected schoolchildren. In 356 schoolchildren (boys/girls: 168/188) aged 9.0-11.5 yr, we determined eNO, total serum IgE, blood eosinophil counts and did skin prick tests (SPT) and spirometry. Parents completed a questionnaire on their children's current or past respiratory symptoms. Atopy was defined by a SPT >3 mm and eosinophilia by a blood cell count above the 80th percentile (>310 cells/ml). eNO levels were about twofold higher in atopic-eosinophilic subjects than in atopic subjects with low blood eosinophils [24.3 p.p.b. (parts per billion) vs. 14.1 p.p.b.] and than non-atopic subjects with high or low blood eosinophils (24.3 p.p.b. vs. 12.2 p.p.b. and 10.9 p.p.b.) (p <0.001 for both comparisons). The additive effect of atopy and high eosinophil count on eNO levels remained unchanged when subjects were analyzed separately by sex or by a positive history of wheeze (n=60), respiratory symptoms other than wheeze (n=107) or without respiratory symptoms (n=189). The frequency of sensitization to Dermatophagoides (Dpt or Dpf) was similar in atopic children with and without eosinophilia (66.2% and 67.4%, respectively); eosinophilia significantly increased eNO levels in Dp-sensitized children as well in children sensitized to other allergens. In a multiple linear regression analysis, eNO levels were mainly explained by the sum of positive SPT wheals and a high blood eosinophil count (t=4.8 and 4.3, p=0.000), but also by the presence of respiratory symptoms (especially wheeze) and male sex (t=2.6 and 2.0, p=0.009 and 0.045, respectively). Measuring eNO could be a simple, non-invasive method for identifying subjects at risk of asthma in unselected school populations.     

Relation of serum and erythrocyte magnesium levels to blood pressure and a family history of hypertension. A follow-up study in Japanese children, 12-14 years old

Serum and erythrocyte magnesium concentrations (S-Mg, E-Mg) were measured in 122 junior high school students followed up for two years from 12 to 14 years of age, and the relationship to blood pressure and a family history of hypertension were investigated. The subjects who had high S-Mg and E-Mg levels at the first examination two years prior tended to show high levels after this follow-up. There were significant positive correlations between two intraindividual values of S-Mg and E-Mg. A similar tendency was found for blood pressure. Tracking phenomena were observed with these measures. The subjects who had high E-Mg levels at the first examination showed no blood pressure elevation during the two-year period. The subjects with a family history of hypertension [FH(+)] showed a higher degree of blood pressure rise during two years than those with no family history [FH(-)], with a significant difference in systolic blood pressure at the age of 14. E-Mg tended to be lower in the FH(+) group than in the FH(-) group with a significant difference in 14-year-old girls. These results suggest that a hereditary predisposition to hypertension is related to magnesium metabolism and that intracellular magnesium deficiency may influence blood pressure elevation in the FH(+) children.