Bayesian consensus clustering for multivariate longitudinal data

In clinical and epidemiological studies, there is a growing interest in studying the heterogeneity among patients based on longitudinal characteristics to identify subtypes of the study population. Compared to clustering a single longitudinal marker, simultaneously clustering multiple longitudinal markers allow additional information to be incorporated into the clustering process, which reveals co-existing longitudinal patterns and generates deeper biological insight. In the current study, we propose a Bayesian consensus clustering (BCC) model for multivariate longitudinal data. Instead of arriving at a single overall clustering, the proposed model allows each marker to follow marker-specific local clustering and these local clusterings are aggregated to find a global (consensus) clustering. To estimate the posterior distribution of model parameters, a Gibbs sampling algorithm is proposed. We apply our proposed model to the primary biliary cirrhosis study to identify patient subtypes that may be associated with their prognosis. We also perform simulation studies to compare the clustering performance between the proposed model and existing models under several scenarios. The results demonstrate that the proposed BCC model serves as a useful tool for clustering multivariate longitudinal data.     

甘草酸及肾十方治疗慢性马兜铃酸肾病26例疗效观察

目的观察甘草酸及复方中药肾十方对慢性马兜铃酸肾病的疗效。方法26例符合慢性马兜铃酸肾病的患者，给予甘草酸二铵150mg加中药复方汤剂肾十方治疗3个疗程。观察治疗前后尿素氮（BUN）、血肌酐（SCr）、尿酶及24h尿蛋白排泄量，血红蛋白、红细胞压积。结果治疗后患者临床症状有显著改善，总有效率80.76％；BUN、SCr、尿N-乙酰葡萄胺酶（NAG）、β2-微球蛋白（β2-MG）均显著下降（P〈0．05），血红蛋白、红细胞压积较治疗前升高（P〈0．05）。结论甘草酸及复方中药肾十方对慢性马兜铃酸肾病有确切的疗效。     

伊贝沙坦与苯那普利、卡托普利对高血压肾病患者尿总蛋白排泄量及内生肌酐清除率影响的比较

目的 :观察伊贝沙坦 (irbesartan)和血管紧张素转换酶抑制剂对高血压肾病患者尿总蛋白排泄量 (UPER)与内生肌酐清除率 (Ccr)的影响 ,比较不同的血管紧张素拮抗剂上述作用的差别。方法 :以序贯试验的方法选择了用伊贝沙坦或苯那普利中卡托普利治疗的高血压肾病患者共 6 6例 ,分为人数相等的 3组 ,进行了治疗前、后 3组间降压效果、UPER、Ccr的比较。结果 :伊贝沙坦了压效果与苯那普利、卡托普利相似 ,但伊贝沙坦对UPER、Ccr的效果优于苯那普利和卡托普利 ,3组比较有统计学的差异 (P <0 .0 1)。伊贝沙坦组未见于干咳现象 ,而苯那普利组及卡托普利组分别干咳发生率分别为 4 .5 %和 13.6 %。结论 :肾功能轻、中度损害的高血压肾病患者服用伊贝沙坦 ,不仅可有效降低血压 ,还可以更好地降低UPER ,提高Ccr。     

Multivariate modelling of responses to conditional items: New possibilities for latent class analysis

Questionnaire data may contain missing values because certain questions do not apply to all respondents. For instance, questions addressing particular attributes of a symptom, such as frequency, triggers or seasonality, are only applicable to those who have experienced the symptom, while for those who have not, responses to these items will be missing. This missing information does not fall into the category ‘missing by design’, rather the features of interest do not exist and cannot be measured regardless of survey design. Analysis of responses to such conditional items is therefore typically restricted to the subpopulation in which they apply. This article is concerned with joint multivariate modelling of responses to both unconditional and conditional items without restricting the analysis to this subpopulation. Such an approach is of interest when the distributions of both types of responses are thought to be determined by common parameters affecting the whole population. By integrating the conditional item structure into the model, inference can be based both on unconditional data from the entire population and on conditional data from subjects for whom they exist. This approach opens new possibilities for multivariate analysis of such data. We apply this approach to latent class modelling and provide an example using data on respiratory symptoms (wheeze and cough) in children. Conditional data structures such as that considered here are common in medical research settings and, although our focus is on latent class models, the approach can be applied to other multivariate models. Copyright © 2009 John Wiley & Sons, Ltd.     

中药肾区渗透并常规治疗高血压性肾损害40例疗效观察

目的：观察中药肾区皮肤外敷渗透加西药常规治疗高血压肾损害结果。方法：将部分中药粉碎微细化处理，将另部分中药液化处理．粉液混合装袋醋浸后外敷在肾区皮肤上，用药物导入仪肾区靶点式导人人体。并用一般西医常规治疗。结果：平均治疗3周血肌酐下降23％，BUN下降26％，24h蛋白尿下降23％，尿量增加16％，收缩压下降9％，舒张压下降7％。结论：中药的肾区皮肤外敷渗透加西医常规治疗效果明显高于一般常规治疗。     

Seasonal variation in the content of a febrifugine and isofebrifugine alkaloid mixture in aerial parts of <Emphasis Type="Italic">Hydrangea macrophylla</Emphasis> var. <Emphasis Type="Italic">Otaksa</Emphasis>, with special reference to its antimalarial activity

Febrifugine and isofebrifugine alkaloid mixtures extracted from the leaves and buds of Hydrangea macrophylla var. Otaksa, collected during different months, in Japan, were quantified using high-performance liquid chromatography. Leaves collected during the flowering season, namely from June to August, contained 0.16–0.31 mg/g of the alkaloid mixture, whereas those collected from September to December had less than 0.03 mg/g of the mixture. However, extracts of buds harvested from October to February contained a consistently larger amount (more than 0.49 mg/g) of the alkaloids. Hot-water extracts from the leaves and buds collected during different seasons were evaluated for antimalarial activity against Plasmodium yoelii 17XL in mice. The extract of leaves collected in August demonstrated high antimalarial activity, and all mice that received the extract survived the infection. In contrast, the extract of leaves collected in December showed little activity. The extract of buds collected in December cleared parasites, but with subsequent mortality to mouse. The present results show that the amount of antimalarial agent—febrifugine and isofebrifugine mixture—in H. macrophylla var. Otaksa is both part- and season-dependent, suggesting that the choice of plant parts and their harvesting season are important factors worth considering in the pharmacological use of medicinal plants.     

地黄合剂降血糖作用的实验性研究

本文通过用四氧嘧啶复制小白鼠糖尿病模型,以血清中血糖及胰岛素水平为指标,研究了地黄合剂对高糖动物的降血糖作用。结果表明,注射四氧嘧啶前小白鼠血糖为173.47±5.23mg/100ml注射后血糖升高至419.78±22.70mg/100ml(P<0.01),差异有高度显著性。实验组服用地黄合剂后,血糖值从410.25±2739mg/100ml下降至313.51±29.39mg/100ml(P<0.05)差异有显著性。因而认为地黄合剂对于四氧嘧啶性糖尿病有显著的降血糖作用。     

糖尿病肾病59例临床分析

本文报告糖尿病367例中并发糖尿病肾病59例占16.1％,近十年来,糖尿病人有增多趋势,糖尿病肾病发生率也显著增加,1966～1976年糖尿病住院治疗的才100例,糖尿病肾病发生率为5％,而1977～1986年有267例,糖尿病肾病发生率为20.2％。经用胰岛素等治疗后好转22例,死亡12例,病死亡率为20.3％,糖尿病肾病除严格控制血糖水平外、无特效疗法。出现持续性旦白尿,病情已到中期或晚期,如何早期诊断是我们今后研究的重要课题。     

温经化瘀合剂临床疗效观察与研究

目的:验证"温经化瘀舍剂"对妇女寒凝血瘀型痛经的治疗效果;方法:将符合中医诊断标准寒凝血瘀型痛经患者,随机分为2组,分别给予"温经化瘀合剂"和"痛经宁冲剂"进行治疗;结果:治疗组总有效率达95%,对照组总有效率80.5%,治疗组优于对照组,治疗组痊愈率48.3%,对照组痊愈率14.6%,治疗组明显优于对照组.实验动物无明显急性毒性反应,能减轻二甲苯引起的小鼠耳肿胀度,减少缩宫素所致大鼠扭体反应次数,和前列腺素E1所致小鼠扭体反应次数,对大鼠离体子宫有双向调节作用,证明"温经化瘀舍剂"具有镇痛、抗炎作用.