Sociodemographic diversity and behavioral medicine

The broad array of economic and cultural diversity in the U.S. population correlates with and impacts on the study of behavioral aspects of health. The purpose of this article was to provide a selective overview of behavioral medicine research on sociodemographically diverse populations, with a focus on ethnicity, gender, and socioeconomic status. Suggestions are provided with regard to methodological refinement of research and insights into possible future directions in behavioral medicine research on ethnically and economically diverse populations.     

The effect of various infertility treatments on the risk of preterm birth

BACKGROUND: The high incidence of preterm birth (<37 weeks gestation) is a major concern in assisted reproductive technology. The objective of this study was to compare the risk of preterm birth from singleton pregnancies following either low technology treatment (intrauterine insemination and donor insemination) or high technology treatment (IVF, ICSI and gamete intra-Fallopian transfer) with that of naturally conceived pregnancies. METHODS: Three cohorts of pregnancies resulting from either low or high technology treatment or from natural conception were included in the study. A number of potential risk factors were adjusted for. RESULTS: The incidence of very preterm birth (<32 weeks of gestation) was not significantly increased in the low technology treatment group (1.0 versus 1.3% in controls) but was significantly higher in the high technology treatment group (5.2%, P < 0.001). In spontaneous, elective Caesarean section (CS) and induced delivery onset, the risk of preterm birth increased gradually from the controls to the low technology treatment group to the high technology treatment group, while for an emergency CS the risk of preterm birth was very high in both treatment groups. CONCLUSIONS: The overall incidence of preterm birth increased significantly from the controls to the low technology treatment group and to the high technology treatment group. Logistic regression analysis showed that younger and older age, previous perinatal death and emergency CS were associated with an increased risk, while a previous live birth reduced the risk. The length of the infertile period did not seem to affect the risk in any of the treatment groups.     

Identification of Bartonella bacilliformis genotypes and their relevance to epidemiological investigations of human bartonellosis

Genotypic diversity among 26 isolates of Bartonella bacilliformis obtained from different areas of Peru, and at different times, was assessed by comparison of DNA sequences derived from 16S-23S ribosomal DNA intergenic spacer regions (ISR) and a citrate synthase gene (gltA) fragment and by amplified fragment length polymorphism (AFLP) analysis. gltA comparison divided the isolates into two groups, whereas ISR comparison revealed six sequences. AFLP analysis using a selective primer delineated five profiles that correlated well with those obtained by sequence comparison. Combination of all three data sets divided the isolates into six genotypes. One of these genotypes was common to isolates collected from a large area in western Peru that corresponded to the region of endemicity for bartonellosis; however, isolates belonging to two other genotypes were also found within this region. Two of these genotypes were found in isolates isolated more than 35 years apart. The remaining three genotypes were each specifically associated with three outbreaks of bartonellosis that have recently occurred in areas where the disease had not previously been recognized. Demonstration of the unique nature of these isolates indicates that the outbreaks with which they were associated did not result from the introduction of disease by individuals who acquired their infection in the recognized region of endemicity. The sources of these outbreaks remain unknown. A consensus approach to bacterial typing using comparative sequence analysis of multiple genetic loci and the pan-genomic sampling of AFLP appears to offer a well-supported assessment of B. bacilliformis diversity, and the genotypic differences identified appear to have epidemiological significance.     

Physiological and behavioral effects of acute ethanol hangover in juvenile, adolescent, and adult rats

This study examined differential responding of juvenile, adolescent, and adult rats after intoxication from an acute alcohol challenge. Experiment I generated blood ethanol curves for subjects 25, 35, or 110 days postnatal, after doses of 2.0 or 4.0 g/kg, assessing elimination rates and time of drug clearance. Experiment 2 compared ethanol's initial hypothermic and delayed hyperthermic effect across age by 48-hr temperature measurement with telemetry. At clearance or 24 hr after alcohol exposure, Experiment 3 tested subjects for changes in acoustic startle reactivity and ultrasonic vocalization (USV). Younger rats showed an absent or reduced tendency for residual hyperthermia, and adults showed alterations in USV observed as aftereffects of intoxication, despite greater initial blood alcohol levels and ethanol hypothermia in the former. The lesser ethanol hangover effects in weanlings and adolescents may be due in part to faster ethanol elimination at these ages compared with adults.