128例双胎妊娠临床结局分析

目的 :探讨影响双胎妊娠临床结局的相关因素。方法 :回顾性分析 12 8例双胎妊娠临床结局与胎方位、分娩方式、孕周、新生儿体重、新生儿窒息之间的关系。 结果 :胎方位、孕周、胎儿体重及分娩方式均影响围产儿预后。 结论 :加强孕产期保健 ,提高产科质量能改善双胎妊娠围产儿的预后。     

Does the Child Behavior Checklist juvenile bipolar disorder phenotype identify bipolar disorder?

BACKGROUND: A profile of Child Behavior Checklist(CBCL) T-scores>or=70 on the attention problems, aggression, and anxious/depressed subscales has been proposed to identify juvenile bipolar disorder(JBD). We tested this hypothesis in a population-based sample. METHODS: Data for this analysis come from a birth-records-based twin sample having semi-structured interview and CBCL data (N=1,346). We compared prevalence of DSM-IV psychiatric disorders and suicidal behaviors in CBCL-JBD and non-CBCL-JBD subjects. Twin modeling assessed genetic and environmental contributions to CBCL-JBD. Associations with DRD4 and DAT1 were examined using chi-square tests. RESULTS: The prevalence of CBCL-JBD was 2.5%. No subjects with CBCL-JBD met criteria for bipolar or other mood disorders. CBCL-JBD subjects had more oppositional defiant disorder (ODD), conduct disorder(CD), and attention deficit hyperactivity disorder(ADHD). The CBCL-JBD profile was uncommon in these disorders. CBCL-JBD subjects more frequently endorsed suicidal behaviors. The CBCL-JBD profile was heritable and associated with the number of DAT1 9-repeat 3' untranslated region alleles. CONCLUSIONS: The CBCL-JBD phenotype does not correspond with a semi-structured interview assessment of JBD. ADHD, CD, and ODD are common in children with CBCL-JBD but do not account for the profile. Increased suicidal behaviors indicate substantial impairment in CBCL-JBD subjects.     

Simultaneous genetic analysis of longitudinal means and covariance structure in the simplex model using twin data

A longitudinal model based on the simplex model is presented to analyze simultaneously means and covariance structure using univariate longitudinal twin data. The objective of the model is to decompose the mean trend into components which can be attributed to those genetic and environmental factors which give rise to phenotypic individual differences and a component of unknown constitution which does not involve individual differences. Illustrations are given using simulated data and repeatedly measured weight obtained in a sample of 82 female twin pairs on six occasions.     

Physical attractiveness and the personality resemblance of identical twins

The physical attractiveness of 25 pairs of monozygotic (MZ) twins was rated independently for twins A and B. The MZ twins were rated alike in their physical attractiveness (r=0.54; corrected for attenuation,r=0.94). Physical attractiveness was uncorrelated with verbal intelligence but was associated, controlling statistically for the sex difference in attractiveness favoring females, with three of the eight traits in the Comrey inventory: Conformity, Extraversion, and Emotional Stability. In both sexes, greater emotional stability was associated with attractiveness; in males greater extraversion; and in females, greater conformity. When these twin correlations were adjusted for this association with attractiveness, the mean change in the value ofr was only 0.03, indicating that physical attractiveness does not appear to bias conclusions from twin studies.     

The Validity of the Neale and Kendler Model-Fitting Approach in Examining the Etiology of Comorbidity

Given that knowledge regarding the etiology of comorbidity between disorders can have a significant impact on research regarding the classification, treatment, and etiology of the disorders, the ability to reject incorrect hypotheses regarding the causes of comorbidity is very important. A simulation study was conducted to assess the validity of the Neale and Kendler (1995) model-fitting approach in examining the etiology of comorbidity between two disorders. First, data were simulated under the assumptions of the 13 alternative comorbidity models described by Neale and Kendler. Second, model-fitting analyses testing the comorbidity models were conducted on the simulated datasets. Thirteen sets of data with varying model parameters were simulated to test Neale and Kendler's assertion that their model-fitting approach is appropriate across a range of potential prevalences and degrees of familiality. The validity of the model-fitting approach in examining unselected twin data and a combination of selected family data and unselected family data was explored. The model-fitting approach successfully discriminated several classes of comorbidity models, although discrimination between models within classes of related models was less accurate. Results suggest that the model-fitting approach can be a useful tool in examining the etiology of the comorbidity between disorders if the caveats of the present study's results are considered carefully. As predicted by Neale and Kendler, variations in the disorder prevalences and familial correlations did not affect the validity of their model-fitting approach, but affected the power to discriminate the correct model. As suggested by Neale and Kendler, the model-fitting approach can be applied to both unselected and selected data and to both twin and family data.     

Editorial: Genetics of Brain Function and Cognition

There is overwhelming evidence for the existence of substantial genetic influences on individual differences in general and specific cognitive abilities, especially in adults. The actual localization and identification of genes underlying variation in cognitive abilities and intelligence has only just started, however. Successes are currently limited to neurological mutations with rather severe cognitive effects. The current approaches to trace genes responsible for variation in the normal ranges of cognitive ability consist of large scale linkage and association studies. These are hampered by the usual problems of low statistical power to detect quantitative trait loci (QTLs) of small effect. One strategy to boost the power of genomic searches is to employ endophenotypes of cognition derived from the booming field of cognitive neuroscienceThis special issue of Behavior Genetics reports on one of the first genome-wide association studies for general IQ. A second paper summarizes candidate genes for cognition, based on animal studies. A series of papers then introduces two additional levels of analysis in the black box between genes and cognitive ability: (1) behavioral measures of information-processing speed (inspection time, reaction time, rapid naming) and working memory capacity (performance on on single or dual tasks of verbal and spatio-visual working memory), and (2) electrophyiosological derived measures of brain function (e.g., event-related potentials). The obvious way to assess the reliability and validity of these endophenotypes and their usefulness in the search for cognitive ability genes is through the examination of their genetic architecture in twin family studies. Papers in this special issue show that much of the association between intelligence and speed-of-information processing/brain function is due to a common gene or set of genes, and thereby demonstrate the usefulness of considering these measures in gene-hunting studies for IQ.