Contagious mastitis

Contagious mastitis is defined. The major mastitis pathogens are Streptococcus agalactiae, Staphylococcus aureus, Corynebacterium bovis, Mycoplasma sp, and Streptococcus dysgalactiae. These pathogens are discussed relative to prevalence, virulence factors, pathology, and control. These control measures include milking time hygiene, segregation, culling, vaccination, and treatment.     

Behavior genetics in Russia

Three children have been reported with a combination of iris coloboma, ptosis, hypertelorism, and growth and mental retardation with possible autosomal recessive inheritance. We report a single case whose clinical features encompass this syndrome and Noonan syndrome, and discuss the possible interpretations of this complex phenotype.     

Gender differences in sexual interest

A common gender stereotype is that males are more interested than females in sex for purely physical reasons. Sociobiologists claim that this difference is biologically determined. In contrast, many sociologists and anthropologists claim that the difference is cultural. The debate about nature versus nurture regarding sexual interest has been long-standing without resolution. We propose a biosocial model that integrates data about nature and nurture to show (i) how several biological factors tilt males and females in different directions related to sexual interest, and (ii) how numerous social factors influence the way the biological tilts can be redirected in countless different ways as individuals grow up in subsets of their culture and subculture. This interactionist approach does not down-play the importance of either biological or social factors: It avoids nature-nurture debates that pit nature against nurture by showing how biological and social factors act in concert, combining their influences. The resulting work contributes to both the theoretical and practical literature, not only showing how sexology can deal with issues of nature and nurture but also providing information useful to people who are troubled about common gender differences in sexual interest.     

Personality genetics

Although 30-60% of the variance in many personality traits is inherited, until recently little was known about the responsible genes. Preliminary studies of family history in bipolar disorder and of X-linkage of personality traits in color-blindness suggested a "quantitative trait locus" (QTL) approach to the genetics of normal personality. In methodically similar but independent studies of 124 Israeli and 315 American normal volunteers we showed an association between the dopamine D4 receptor gene (D4DR) and the personality trait of novelty seeking. In the Israeli sample we also found an interaction between the D4DR gene and the serotonin 2C receptor gene (5-HT2C) with a marked effect on the trait of reward dependence. Further investigation of genes for personality traits may suggest links between normal personality and psychiatric illness.     

Statistical methods in psychiatric genetics

Most psychiatric disorders are determined by the complex interplay between genetic and environmental factors. Aetiological research into these complex disorders raises many different questions which require a variety of statistical methods. These include survival analysis for the estimation of morbid risk, structural equation models for the partitioning of phenotypic variances and covariances into genetic and other components, complex segregation analysis to detect loci of major effect, and linkage and association analysis for the localisation and identification of susceptibility genes. Future developments in psychiatric genetics will involve the integration of genetic and epidemiological statistics in order to study the interplay between genetic and environmental factors in the complex pathways which lead to mental disorders.     

Systematic gain-of-function genetics in Drosophila

A modular misexpression system was used to carry out systematic gain-of-function genetic screens in Drosophila. The system is based on inducible expression of genes tagged by insertion of a P-element vector carrying a GAL4-regulated promoter oriented to transcribe flanking genomic sequences. To identify genes involved in eye and wing development, the 2300 independent lines were screened for dominant phenotypes. Among many novel genes, the screen identified known genes, including hedgehog and decapentaplegic, implicated in these processes. A genetic interaction screen for suppressors of a cell migration defect in a hypomorphic slow border cells mutant identified known genes with likely roles in tyrosine kinase signaling and control of actin cytoskeleton, among many novel genes. These studies demonstrate the ability of the modular misexpression system to identify developmentally important genes and suggest that it will be generally useful for genetic interaction screens.     

Conflicts of interest

Hormonal effects on the functional status and working capacity were found in girls with juvenile dysfunctional uterine hemorrhage who had been exposed to ionizing radiation in early childhood, in those with primary hyperthyroidism and healthy athletic girls in different phases of a menstrual cycle. Whether the hormonal status might be corrected by interval hypoxic training was examined. There was a relationship of respiratory functional changes to the phases of a menstrual cycle in healthy girls. Impaired external respiratory function, blood flow, and blood respiratory function, lower oxygen consumption were found in girls who had been victims of the Chernobyl accident and respiratory functional changes were detected in patients with hypothyroidism. It was ascertained that interval hypoxic training was an effective alternative to mountain training, that it promoted higher aerobic and anaerobic productivity and special working capacity in athletes. An interval hypoxic training course was found to substantially improve oxygen regimens in girls with secondary anemia, to elevate hemoglobin levels to normal values, to recover normal ovarian function. It also enhanced the production of thyroid hormones, normalized oxygen consumption, improved the patients' condition, increased physical and mental performance in patients with hypothyroidism.     

The role of interest in learning from scientific text and illustrations: On the distinction between emotional interest and cognitive interest.

A textbook lesson may be made more interesting by promoting emotional interest through adding entertaining text and illustrations or by promoting cognitive interest through adding signals for structural understanding such as summary illustrations with captions. In Experiment 1, skilled readers who read summary text and illustrations about the process of lightning performed worse on retention of important information and on transfer when entertaining text, illustrations, or both were added. In Experiment 2, skilled readers rated entertaining text and illustrations relatively high in emotional interest and low in cognitive interest and rated summary illustrations and text relatively low in emotional interest and high in cognitive interest. The results suggest benefits of cognitive interest over emotional interest for helping students learn scientific explanations. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Comparative genetics in the grasses

Genetic mapping of wheat, maize, and rice and other grass species with common DNA probes has revealed remarkable conservation of gene content and gene order over the 60 million years of radiation of Poaceae. The linear organization of genes in some nine different genomes differing in basic chromosome number from 5 to 12 and nuclear DNA amount from 400 to 6,000 Mb, can be described in terms of only 25 "rice linkage blocks." The extent to which this intergenomic colinearity is confounded at the micro level by gene duplication and micro-rearrangements is still an open question. Nevertheless, it is clear that the elucidation of the organization of the economically important grasses with larger genomes, such as maize (2n = 10, 4,500 Mb DNA), will, to a greater or lesser extent, be predicted from sequence analysis of smaller genomes such as rice, with only 400 Mb, which in turn may be greatly aided by knowledge of the entire sequence of Arabidopsis, which may be available as soon as the turn of the century. Comparative genetics will provide the key to unlock the genomic secrets of crop plants with bigger genomes than Homo sapiens.     

Differential interest patterns in salesmen.

Significant intergroup differences on 7 of the scales of the SVIB were found among 3 types of salesmen (specialty salesmen, route salesmen, sales engineer—each n = 100); common characteristics were found for 5 of the scales. "The results of this study support the trend away from the concept of salesmen in general toward the concept of special sales occupational groups." (PsycINFO Database Record (c) 2010 APA, all rights reserved)