Ventricular function

Multiple modalities contribute to the evaluation of ventricular function. The role of cineangiography, echocardiography, MR imaging, ultrafast CT, and nuclear medicine continue to evolve and improve our understanding of the physiology and pathophysiology of ventricular function. This article discusses the use and limitation of each modality.     

Summary of analyses of problem 2 simulated data for GAW11

The simulated data for Problem 2 of the 11th Genetic Analysis Workshop (GAW11) consisted of family linkage data and disease data from three populations, each population with different genetic parameters. The disease was simulated such that there were two genetically distinct diseases, one caused by a single locus with three alleles and the other by two epistatically interacting loci. The two diseases were clinically identical. Each of the diseases had a severe and mild form. One of the diseases was influenced by an environmental factor and one by an allele at one of the marker loci (association). Linkage data consisted of 300 polymorphic markers. Investigators analyzed these data in a myriad of ways, using most currently available linkage techniques and association analysis methods. In addition, investigators also tested newly developed methods, some of which took advantage of the existence of the environmental component. Other types of analyses included meta-analyses, methods of combining data from different studies, questions of replication, how much information is available in a single data set, and analyses for gene x gene and gene x environment interaction.     

Transgenic models for prostate cancer research

The ability to introduce novel or specifically altered genes into the germ line of mice and directly perturb gene expression in a specific tissue can facilitate characterization of the molecular mechanisms governing transformation of differentiating tissue within the context of an intact developing animal. Transgenics provide a powerful and remarkably flexible system that can be used to study the cooperation between proto-oncogenes, tumor suppressor genes, and other epigenetic factors in the development of cancer.     

Neophobia in the foraging-site selection of a neotropical migrant bird: An experimental study

I hand-raised chestnut-sided warblers (Dendroica pensylvanica) in a room with eight experimental microhabitats; the microhabitats were removed after 6 weeks. I then measured the response of the warblers to the eight “natal” and eight “novel” microhabitats in two experiments conducted 2 and 4 months after removal. Chestnut-sided warblers responded with decreased feeding latency (neophobia) and a greater preference for foraging at the natal microhabitats. I suggest that an ontogenetic increase in neophobia restricts chestnut-sided warblers to foraging at microhabitats most similar to those experienced as juveniles.     

Drug Regulation Reform Act of 1978

Provisions of the Drug Regulation Reform Act of 1978 are discussed. Included in the discussion are drug monographs and product licenses, investigations and approvals of drugs, drug information, labeling, promotion and education, penalties, and the National Center for Clinical Pharmacology. The Act eliminates the individual NDA approach to regulation and replaces it with a system of monographs on "drug entities" and "drug product" licenses. It amplifies and redefines the investigational process to facilitate and promote research while protecting patients' rights. It also divides the commercial investigation process into two phases: drug innovation investigations and drug development investigations.     

Experimental analysis of the ‘happy hour’: Effects of purchase price on alcohol consumption

An experimental analogue of a discount drink policy known as the happy hour was used to study the effects of purchase price on drinking behavior. Male volunteers with a prior history of either casual (N=20) or heavy (N=14) drinking were given free access to beverage alcohol during a 20-day period. Approximately half the subjects could purchase alcohol under a single-price condition (50 ¢/drink), while a matched group was given a price reduction daily (25 ¢/drink) during a three-hour period in the afternoon. The results demonstrated that the afternoon price reduction significantly increased alcohol consumption in both casual and heavy drinkers. Reinstatement of the standard purchase price effectively suppressed drinking in both groups. The findings are discussed in terms of the theoretical and research implications of environmental influences on drinking.     

Do alexithymic traits predict illness?

The common theoretical speculation that alexithymic personality characteristics (impoverished fantasy life and difficulty expressing feelings verbally) lead to psychosomatic disease was tested in a sample of 181 men. Unlike previous investigations, this study used a measure of alexithymic characteristics taken at least 1 year before any of the men became ill. Comparisons were made of the premorbid MMPI alexithymia scale scores of groups of men who remained well for 10 years or within 10 years developed either physical illness (cancer or benign tumors), "classical" psychosomatic disease (hypertension or gastrointestinal ulcers), or psychiatric disorder (schizophrenia). Results did not support the notion that alexithymia leads to illness onset. There were no significant differences among the groups in their premorbid alexithymia scores. Furthermore, the groups did not differ in the percentage of individuals labeled alexithymic with the use of previously established cut-off points. Although the findings cast doubt on alexithymia as a cause of illness, they do not conflict with the idea that alexithymia can result from the stress of disease or that this type of personality configuration may lead to a decreased response to treatment and a prolonged course of illness.