Early life markers of atopy and asthma

Since early intervention could modulate the natural course of atopic disease, the availability of predictive markers is of considerable interest. As long as specific genetic markers are not available, early IgE-responses (hen's egg) together with a positive family history of atopy can be proposed as highly specific and predictive markers, which could define subgroups as potential candidates for secondary prevention.     

基于EEG模糊相似性的癫痫发作预测

本研究提出基于EEG序列模糊相似性指数方法预测癫痫发作.首先,结合复自相关法和Cao法对EEG序列进行了相空间重构;然后,计算相关积分时用Gaussian函数代替Heavyside函数,克服了Heavyside函数的刚性边界问题,使得计算相似性指数更加准确和可靠;最后,分析大鼠癫痫EEG信号,检测癫痫发作前期状态.分析结果表明模糊相似性指数方法能够比动态相似性指数方法获得更长的预测时间和更低的错误预测率.     

Lp(a) lipoprotein level predicts survival and major coronary events in the Scandinavian Simvastatin Survival Study

The Scandinavian Simvastatin Survival Study (4S) was a double-blind. randomized placebo-controlled multi-centre clinical trial of long-term Simvastatin therapy in patients with coronary heart disease who had total cholesterol levels between 5.5 and 8.0 mmol/1, comprising 4444 patients, equally distributed to a Simvastatin and a placebo group. Patients achieved a significant 30% relative reduction in overall mortality with Simvastatin therapy through a 42% relative reduction in coronary heart disease mortality. Lp(a) lipoprotein levels in Scandinavian coronary heart disease patients were strikingly higher than in healthy controls. Numbers of deaths in the Simvastatin group differed significantly between quartiles of Lp(a) lipoprotein levels, the reduction in deaths being most pronounced in the second (next to lowest) quartile. Subjects with major coronary events had significantly higher Lp(a) lipoprotein levels than subjects without such events, in all groups. The relationship between Lp(a) lipoprotein level and total mortality as well as between Lp(a) lipoprotein level and major coronary events was significantly different from zero, in logistic regression analyses. The findings show that Lp(a) lipoprotein predicts major coronary events as well as death in secondary prevention with Simvastatin. This prospective study provides independent confirmation that a high Lp(a) lipoprotein level is a significant coronary heart disease risk factor.     

基因功能预测问题中的样本不平衡处理

应用机器学习进行分类是基因功能预测的一种重要手段。但是许多预测集中的阳性样本过少，会降低功能预测的效果。针对此问题，本研究对结合支持向量机（SVM）算法的几种常用非平衡数据分类方法进行实验比较，包括投票整合分类器和移动分类面等。在此基础上提出通过加权修正投票的整合策略，以提高预测效果。实验结果显示，结合多数类样本限数取样及整合思想的投票整合法预测效果优于移动分类面法，而在投票整合法基础上的加权修正整合方法在所有方法中获得更好更稳定的结果。     

Establishment of predictive variables associated with testicular sperm retrieval in men with non-obstructive azoospermia

Although testicular biopsy for sperm extraction is a procedure with a potential for complications, sperm retrieval is successful in 30-70% of patients with non-obstructive azoospermia. In order to predict the probability of retrieving at least one testicular spermatozoon we conducted a prospective study of a set of variables in 40 patients with non-obstructive azoospermia. Using the receiver operating characteristic curves, we determined the probability estimates of testicular volume, plasma follicle stimulating hormone (FSH) concentration, Johnsen score and visualization of testicular spermatids in discriminating between patients with successful and failed testicular sperm extraction. Visualization of testicular spermatids provided the best estimate of success of testicular sperm extraction. Of the factors studied using logistic-regression analysis (age, maternal and paternal age at birth, body mass index, luteinizing hormone, testosterone, FSH, testicular volume, the presence of testicular spermatids and Johnsen score), only the presence of spermatids and Johnsen score were independent variables able to predict the success of testicular sperm extraction. The visualization of the presence of spermatids gave a correct prediction of 77% and Johnsen score of 71%. The diagnostic model derived from these independent predictors when validated in 40 patients using the Jackknife technique gave a correct overall prediction of 87%. The probability of successful testicular sperm extraction in patients with non-obstructive azoospermia could be objectively predicted on the basis of simple histopathological criteria represented by the visualization of testicular spermatids and Johnsen score.     

Total ovarian volume before human chorionic gonadotrophin administration for ovulation induction may predict the hyperstimulation syndrome

Total ovarian volumes were measured before the administrationof HCG in 42 women undergoing treatment for infertility by in-vitrofertilization (IVF) and embryo transfer and considered to havean exaggerated response to stimulation (>20 follicles). Sevenwomen who subsequently developed moderate or severe ovarianhyperstimulation syndrome (OHSS) (n = 7; group 1) were comparedwith 35 matched controls (five matched controls per case; n= 35; group 2) of similar age, number of follicles and durationof infertility who underwent follicular stimulation, oocyterecovery, in-vitro fertilization and embryo transfer duringthe same period but did not develop moderate or severe OHSS.The mean age, duration of infertility and total number of follicleswere similar but the mean total ovarian volume was significantlyhigher in the group of women who developed moderate or severeOHSS compared with controls (271.00 ± 87.00 versus 157.30± 54.20 ml; P < 0.01). We conclude that total ovarianvolume measured before HCG administration is higher in womenwho develop moderate or severe OHSS compared with controls andmay therefore be used as an additional parameter in the preventativestrategy for the ovarian hyperstimulation syndrome.     

Predictability of Individual Differences in Activation Processes in a Field Setting Based on Laboratory Measures

The predictability of individual differences in activation processes was investigated in a multi-method laboratory-field study. Male students of physical education (N=58) were examined under various emotionally activating and physically demanding conditions (mental arithmetic, reaction time, free speech, cold pressor test, bicycle ergometer). The assessment included multi-channel recordings of pre-start phases in an athletic stadium and performance on a 1000 m run. Basal heart rate was also recorded during sleep. This multi-situational assessment was repeated after three weeks, three months, and, for most (N=42) subjects, after one year. Significant relationships exist between scores from corresponding conditions of relaxation, anticipation, and performance of physical exercise. However, with the exception of heart rate, correlation coefficients are rather small and seem to be of questionable predictive validity. A generalizability study further supports the general conclusion: To increase the practical relevance in psychophysiological investigations of stress/strain phenomena, such studies should directly assess individual differences in the criterion situations themselves.     

利用神经网络集成预测MHC-Ⅰ类分子结合肽

目的：利用神经网络集成（NNE）预测MHC-Ⅰ类分子结合肽。 方法： 基于HLA-A*0201编码的MHC-Ⅰ类分子结合肽数据库（含有628个9聚物）及其结合能力分类，利用NNE分别对具有无、低、中和高4类亲合性的结合肽进行分类预测；同时还进一步利用T细胞真实表位集（含50个表位）评估了NNE的预测性能。 结果： 集成数为12的NNE对上述分类的平均预测命中率可达0.8,而且NNE对潜在T细胞表位的预测能力也较高，约84%的真实表位归于高和中等亲合性的潜在抗原肽一类。 结论： 可以利用神经网络集成预测MHC-Ⅰ类分子结合肽，并进而预测相应的T细胞表位。经适当修改，NNE预测工具可扩展为能涵盖任意长度的Ⅰ类分子结合肽甚至可扩展到Ⅱ类分子结合肽的预测。     

Cord blood IgE. III. Prediction of IgE high-response and allergy

Screening of total IgE in 2814 cord blood samples was analysed by Phadebas IgE PRIST in 2 1-year birth cohorts (1983–1984 and 1985–1986) in Denmark (n= 1189 + 1625). For follow-up we chose all infants with cord blood IgE≥0.5 kU/1 and a randomly chosen group of the same size with cord blood IgE < 0.5 kU/1. A total group of 762 infants were clinically evaluated at 18 months of age, and in 688 of these we evaluated total and specific IgE. A diagnosis of definite atopy, probable atopy or no atopy was established. In the present study we defined allergic disease as atopic disease combined with elevated total IgE. We found a statistically significant correlation between cord blood IgE and IgE at 18 months of age. Significantly more infants with elevated cord blood IgE had developed allergic disease at 18 months. A cut-off value of 0.3 kU/1 for cord blood IgE was superior to the originally suggested 0.5 kU/1. Significantly more infants with elevated cord blood IgE had developed specific IgE antibodies at 18 months. The most frequent specific IgE antibody was towards cow's milk. Specific IgE antibodies were very rarely found when total IgE was not elevated. A total IgE at the age of 18 months > 26 kU/1 could be regarded as elevated. With regard to allergic disease the positive predictive values of cord blood lgE≥0.3 kU/1 in the 2 series were 21 % and the corresponding sensitivities 67% and 46%, respectively. The risk of developing allergic disease was elevated with a factor 3 to 4 when cord blood IgE ≥ 0.3 kU/1. In a high-risk group based on atopic predisposition and elevated eord blood IgE ≥0.5 kU/1 the relative risk of allergic disease was 5, the predictive value of positive test 38%, the sensitivity 24% and the specificity 96%. Clinical aspects Cord blood IgE was a good predictor of allergic disease at the age of 18 months. A cord blood cut-off IgE value of 0.3 kU/l was superior to other cord blood IgE values with the Phadebas IgE PRIST method.     

Patient involvement in oral hygiene cooperation: a factor analytic study

In a previous study the concept "patient involvement" was found to be strongly predictive of therapy outcome. On the basis of a questionnaire concerning patients' background and motivation, 82 patients were interviewed before treatment. To cover the concept "patient involvement" 16 variables were considered as relevant measures. In a factor analysis four factors accounted for 90% of the common variance. The factors were interpreted in terms of: initial attitudes, attendance, self-confidence and teeth-mindedness.