Behavioral and social sciences theories and models: are they used in unintentional injury prevention research?

Behavioral and social sciences theories and models have the potential to enhance efforts to reduce unintentional injuries. The authors reviewed the published literature on behavioral and social science theory applications to unintentional injury problems to enumerate and categorize the ways different theories and models are used in injury prevention research. The authors conducted a systematic review to evaluate the published literature from 1980 to 2001 on behavioral and social science theory applications to unintentional injury prevention and control. Electronic database searches in PubMed and PsycINFO identified articles that combined behavioral and social sciences theories and models and injury causes. The authors identified some articles that examined behavioral and social science theories and models and unintentional injury topics, but found that several important theories have never been applied to unintentional injury prevention. Among the articles identified, the PRECEDE PROCEED Model was cited most frequently, followed by the Theory of Reasoned Action/Theory of Planned Behavior and Health Belief Model. When behavioral and social sciences theories and models were applied to unintentional injury topics, they were most frequently used to guide program design, implementation or develop evaluation measures; few examples of theory testing were found. Results suggest that the use of behavioral and social sciences theories and models in unintentional injury prevention research is only marginally represented in the mainstream, peer-reviewed literature. Both the fields of injury prevention and behavioral and social sciences could benefit from greater collaborative research to enhance behavioral approaches to injury control.

Altered localization of retinoid X receptor alpha coincides with loss of retinoid responsiveness in human breast cancer MDA-MB-231 cells.

To understand the mechanism of retinoid resistance, we studied the subcellular localization and function of retinoid receptors in human breast cancer cell lines. Retinoid X receptor alpha (RXR alpha) localized throughout the nucleoplasm in retinoid-sensitive normal human mammary epithelial cells and in retinoid-responsive breast cancer cell line (MCF-7), whereas it was found in the splicing factor compartment (SFC) of the retinoid-resistant MDA-MB-231 breast cancer cell line and in human breast carcinoma tissue. In MDA-MB-231 cells, RXR alpha was not associated with active transcription site in the presence of ligand. Similarly, ligand-dependent RXR homo- or heterodimer-mediated transactivation on RXR response element or RARE showed minimal response to ligand in MDA-MB-231 cells. Infecting MDA-MB-231 cells with adenoviral RXR alpha induced nucleoplasmic overexpression of RXR alpha and resulted in apoptosis upon treatment with an RXR ligand. This suggests that nucleoplasmic RXR alpha restores retinoid sensitivity. Epitope-tagged RXR alpha and a C-terminus deletion mutant failed to localize to the SFC. Moreover, RXR alpha localization to the SFC was inhibited with RXR alpha C-terminus peptide. This peptide also induced ligand-dependent transactivation on RXRE. Therefore, the RXR alpha C terminus may play a role in the intranuclear localization of RXR alpha. Our results provide evidence that altered localization of RXR alpha to the SFC may be an important factor for the loss of retinoid responsiveness in MDA-MB-231 breast cancer cells.

Child and adolescent injury research in 1998: a summary of abstracts submitted to the Ambulatory Pediatrics Association and the American Public Health Association.

OBJECTIVE: To describe current research in child and adolescent injury prevention by pediatric and public health investigators for comparison with national recommendations and agendas. DATA SOURCES: Abstracts submitted to the 1998 annual meetings of the Pediatric Academic Societies/Ambulatory Pediatrics Association and the American Public Health Association on injury or violence in children or adolescents. STUDY SELECTION: All abstracts of projects that addressed primarily injury or violence prevention involving children or adolescents. DATA EXTRACTION: For 123 abstracts, 2 coauthors extracted and classified age of the population, type of injury, study design, sizes of the sample and denominator, and type of outcome. RESULTS: Adolescents were the most frequent (49%) age group included. The investigations were concerned most with injuries caused by violence (33%), followed by motor vehicle trauma (14%) and burns (7%). Descriptive surveillance (38%), surveys (32%), and case series (13%) comprised the overwhelming majority of methods used. The studies primarily sought to identify risk factors for injury (32%), describe the victims (20%), or measure knowledge and/or practice (26%). Nine studies (7%) sought to measure the effect of interventions in some way, and only 2 focused primarily on methodology development. CONCLUSIONS: Injury prevention research projects presented at the 1998 Pediatric Academic Societies and American Public Health Association meetings were proportionate to the frequencies of injury by age and by external cause in the United States. However, in comparison with recommendations for agendas of national injury prevention research, more research is needed to improve injury prevention methods and to evaluate interventions.

Ovariectomy increases squamous metaplasia of the uterine horns and survival of SENCAR mice fed a vitamin A-deficient diet.

BACKGROUND: Retinoic acid is necessary for the growth and differentiation of organisms and exerts its molecular actions by binding to specific nuclear receptors that belong to the thyroid-steroid hormone receptor superfamily. Steroids and retinoids control the differentiation of the female reproductive epithelia: estrogen maintains the squamous differentiation of vaginal and ectocervical epithelia, whereas retinoic acid maintains the simple columnar endocervical and uterine epithelia. These lining epithelia transform into a squamous metaplastic phenotype in vitamin A-deficient animals. Furthermore, mortality due to vitamin A deficiency is usually attributed to infection resulting in part from dysfunction of the protective epithelia. OBJECTIVE: Our objective was to test the hypothesis that estrogen depletion might change the squamous metaplastic response to vitamin A deficiency and affect animal survival. DESIGN: We used female SENCAR mice maintained on a purified vitamin A-deficient diet containing either 0 or 3 microg retinoic acid/g diet. Mice were either ovariectomized or intact. Squamous cells arising in the normally simple columnar epithelium of the endocervix and uterine cavity were monitored by keratin 5 expression with immunohistochemistry. RESULTS: Ovariectomy did not change the time to onset of vitamin A deficiency. It increased the number of squamous metaplastic cells and prolonged survival in mice consuming a vitamin A-deficient diet by as much as 40%. CONCLUSIONS: Factors other than epithelial differentiation per se control survival outcome of vitamin A-deficient mice. The results also show a significant increase in longevity of vitamin A- deficient mice when ovariectomized.

Risk factors for infant homicide in the United States.

BACKGROUND: Homicide is the leading cause of infant deaths due to injury. More than 80 percent of infant homicides are considered to be fatal child abuse. This study assessed the timing of deaths and risk factors for infant homicide. METHODS: Using linked birth and death certificates for all births in the U.S. between 1983 and 1991, we identified 2776 homicides occurring during the first year of life. Birth-certificate variables were reviewed in both bivariate and multivariate stratified analyses. Variables potentially predictive of homicide were selected on the basis of increased relative risks among subcategories with adequate numbers for stable estimates. RESULTS: Half the homicides occurred by the fourth month of life. The most important risk factors were a second or subsequent infant born to a mother less than 17 years old (relative risk, 10.9) or 17 to 19 years old (relative risk, 9.3), as compared with a first infant born to a mother 25 years old or older; a maternal age of less than 15 years, as compared with an age of at least 25 years (relative risk, 6.8); no prenatal care as compared with early prenatal care (relative risk, 10.4); and less than 12 years of education among mothers who were at least 17 years old (relative risk, 8.0), as compared with 16 or more years of education. CONCLUSIONS: Childbearing at an early age was strongly associated with infant homicide, particularly if the mother had given birth previously. Our findings may have implications for prevention.