Biomedical subjects

Amy L Davidow

Publications and source records attributed to Amy L Davidow.

6 recordsLinked to original sources

PubMed2004

Ethnic differences in insulin sensitivity and beta-cell function in premenopausal or early perimenopausal women without diabetes: the Study of Women's Health Across the Nation (SWAN).

OBJECTIVE: To assess differences in insulin sensitivity and beta-cell function between nondiabetic premenopausal or early perimenopausal non-Hispanic white women and African American, Chinese American, Japanese American, and non-Mexican-American Latino women. RESEARCH DESIGN AND METHODS: Homeostasis model assessments (HOMAs) of insulin sensitivity (HOMA%S) and beta-cell function (HOMA%beta) were used. Stepwise multivariable ethnic-specific ANCOVA models were used to compare HOMA%S and HOMA%beta between non-Hispanic whites and each of the four ethnic groups. RESULTS: HOMA%S was lower in African Americans, Chinese Americans, and Japanese Americans when compared with non-Hispanic white women after correcting for waist circumference, presence of impaired fasting glucose, and site. Significant differences persisted only between African Americans and non-Hispanic whites after inclusion of triglycerides in the model. Triglycerides indirectly corrected for the differences in HOMA%S in the other two groups. There were no differences in HOMA%S between the non-Mexican-American Latinos and the non-Hispanic whites. Japanese Americans and Chinese Americans had lower HOMA%beta than non-Hispanic whites, whereas African Americans had higher HOMA%beta than non-Hispanic whites after correcting for confounders. HOMA%beta was similar between non-Mexican-American Latinos and non-Hispanic whites. CONCLUSIONS: These data suggest that type 2 diabetes prevention strategies for African-American women should initially target decreased insulin sensitivity, whereas strategies for Japanese-American and Chinese-American women may initially need to target both decreased insulin sensitivity and beta-cell function. Previous studies of Mexican-American populations may not apply to non-Mexican-American Latino women.

Adult↗

PubMed2004

Airborne infection with Bacillus anthracis--from mills to mail.

The lack of identified exposures in 2 of the 11 cases of bioterrorism-related inhalation anthrax in 2001 raised uncertainty about the infectious dose and transmission of Bacillus anthracis. We used the Wells-Riley mathematical model of airborne infection to estimate 1) the exposure concentrations in postal facilities where cases of inhalation anthrax occurred and 2) the risk for infection in various hypothetical scenarios of exposure to B. anthracis aerosolized from contaminated mail in residential settings. These models suggest that a small number of cases of inhalation anthrax can be expected when large numbers of persons are exposed to low concentrations of B. anthracis. The risk for inhalation anthrax is determined not only by bacillary virulence factors but also by infectious aerosol production and removal rates and by host factors.

Air Microbiology↗

PubMed2004

Youth homicide racial disparities: gender, years, and cause.

OBJECTIVE: To study racial disparities and the weapons used to commit youth homicide in New Jersey. METHODS: The homicide data were obtained from New Jersey death certificate files, 1989-1997. RESULTS: There was a statistically significant racial disparity in homicide incidence rates in this study. The homicide incidence rates was 10 times and four times higher among African-American than white, adolescents (age 15-19 years) and young adults (age 20-24 years) (respectively). Youth (15-24 years) homicide incidence rate correlated with New Jersey's 21 counties' high urbanization index and with low level of education. The ratio of male/female homicide incidence rates was 6:4 for adolescents and young adults, respectively. African-American adolescent homicide rates increased consistently from 1989 to 1997. Sixty percent of all youth homicide was committed by firearms. CONCLUSION: Significant youth homicide racial and gender disparities exist in New Jersey's 21 counties. If the existing trend of homicide violent crime victimization continues in New Jersey, African-American teenagers will soon become the leading segment of the population to be murdered in the state. Sixty percent of the youth homicide victimization was committed by firearms; and correlation analyses of New Jersey's 21 counties suggested that low levels of education and high levels of urbanization provided an environment of key risk factors for homicide.

Adolescent↗

PubMed2003

Lead exposure potentiates predatory attack behavior in the cat.

Epidemiologic studies have demonstrated that environmental lead exposure is associated with aggressive behavior in children; however, numerous confounding variables limit the ability of these studies to establish a causal relationship. The study of aggressive behavior using a validated animal model was used to test the hypothesis that there is a causal relationship between lead exposure and aggression in the absence of confounding variables. We studied the effects of lead exposure on a feline model of aggression: predatory (quiet biting) attack of an anesthetized rat. Five cats were stimulated with a precisely controlled electrical current via electrodes inserted into the lateral hypothalamus. The response measure was the predatory attack threshold current (i.e., the current required to elicit an attack response on 50% of the trials). Blocks of trials were administered in which predatory attack threshold currents were measured three times a week for a total of 6-10 weeks, including before, during, and after lead exposure. Lead was incorporated into cat food "treats" at doses of 50-150 mg/kg/day. Two of the five cats received a second period of lead exposure. Blood lead concentrations were measured twice a week and were <1, 21-77, and <20 micro g/dL prior to, during, and after lead exposure, respectively. The predatory attack threshold decreased significantly during initial lead exposure in three of five cats and increased after the cessation of lead exposure in four of the five cats (P<0.01). The predatory attack thresholds and blood lead concentrations for each cat were inversely correlated (r=-0.35 to -0.74). A random-effects mixed model demonstrated a significant (P=0.0019) negative association between threshold current and blood lead concentration. The data of this study demonstrate that lead exposure enhances predatory aggression in the cat and provide experimental support for a causal relationship between lead exposure and aggressive behavior in humans.

Aggression↗

PubMed2003

Rethinking the socioeconomics and geography of tuberculosis among foreign-born residents of New Jersey, 1994-1999.

OBJECTIVES: This study investigated the socioeconomic profile of foreign-born tuberculosis patients in New Jersey. METHODS: Foreign- and US-born tuberculosis patients in 1994-1999 were compared using various measures of socioeconomic status. RESULTS: Out of 4295 tuberculosis patients, 2005 (47%) were foreign-born. Foreign-born patients resided in more affluent, more educated, and less crowded areas than did US-born patients (P <.005). They were also more likely to have been employed during the 2 years before diagnosis (62% vs 41%, P <.001). Private physicians treated the majority of South Asian-born patients. CONCLUSIONS: Substantial numbers of employed foreign-born tuberculosis patients now reside in affluent New Jersey locations. Changes in tuberculosis control programs may be required when the socioeconomic status and place of residence of foreign-born populations diverge from traditional assumptions linking poverty with tuberculosis.

Adolescent↗

PubMed2002

Loss of chromosome 16 from renal epithelial cells in humans.

This work explores the notion that low-frequency, acquired aneuploidy may play a role in complex genetic traits such as essential hypertension. To this end, renal epithelial cells in urinary sediments and in renal cysts were examined by fluorescent in situ hybridization with DNA probes specific for the heterochromatic and centromere regions of chromosomes 16 and 1. Chromosome 16 was probed because it harbors variant genes causing monogenic hypertension. These genes have also been investigated for their role in essential hypertension. Chromosome 1 was also probed as an internal control. Higher proportions of renal epithelial cells in the urinary sediments showed monosomy of chromosome 16 than monosomy of chromosome 1 (P<0.001). We also observed in epithelial cells of renal cysts a preponderance of monosomy for chromosome 16 over monosomy for chromosome 1 (P<0.024). Low-frequency loss of heterozygosity that results from acquired monosomy of chromosome 16 and perhaps other chromosomes may contribute to expression of complex genetic traits such as essential hypertension, in which the diverse phenotypic manifestations are poorly understood.

Adolescent↗