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Biomedical subjects

R A Bell

Publications and source records attributed to R A Bell.

At least 73 records · Page 4Linked to original sources
PubMed1997

The impact of the Wellness Guide/Guía on Hispanic women's well-being-related knowledge, efficacy beliefs, and behaviors: the mediating role of acculturation.

This study examined how acculturation mediated the impact of the California Wellness Guide/La Guía del Bienestar on Hispanic women's knowledge, efficacy beliefs, and behaviors. Knowledge gaps were found between acculturated and less acculturated women. Acculturated mothers had more confidence in their abilities to acquire wellness-related information both before and after Guide/Guía distribution and also had more assistance-seeking efficacy. Guide/Guía recipients were more knowledgeable, had greater confidence in their knowledge and their abilities to acquire information, and possessed better information acquisition strategies than nonrecipients. The publication also enhanced low-acculturated recipients' assistance-seeking self-efficacy. High-acculturated and low-acculturated recipients of the Guide/Guía were equally likely to have retained and used their copies, to anticipate using the publication in the future, and to have made a change in behavior as a result of the guide. Finally, the Guide/Guía did not increase the knowledge gap between high- and low-acculturated guide recipients.

Acculturation↗
PubMed1997

Physicians' attitudes toward managed care: assessment and potential effects on practice behaviors.

This study was designed to identify the key components of physicians' attitudes toward managed care and develop a tool to assess these components. We developed a questionnaire based on physicians' reactions to managed care, as reflected in the published literature. We mailed this questionnaire to a sample of 753 community physicians in the greater Sacramento area. A factor analysis of these data (n = 315) identified five unifactorial scales, which we labeled managed care quality, need to adapt to managed care, cost-containment effectiveness of managed care, personal knowledge of managed care, and inevitability of managed care. Physicians were most negative about the quality of managed care and most in agreement about the need to adapt to it. Correlations among these five scales, while statistically significant, were modest in size, suggesting that these physicians were quite discriminating in their evaluations. In comparison with medical/surgical specialists, primary care physicians rated the quality of managed care, their knowledge of it, and the inevitability of a national transition to managed care more positively. These measures predicted the physicians' intentions to alter their medical behaviors to comply with managed care practices.

Attitude of Health Personnel↗
PubMed1996

Coronary heart disease risk factors in black and white patients with non-insulin-dependent diabetes mellitus.

OBJECTIVE: To determine possible racial differences in risk factors for coronary heart disease (CHD) in black and white patients with noninsulin-dependent diabetes mellitus (NIDDM). METHODS: Study of risk factors for coronary heart disease among 308 subjects who met the WHO criteria for NIDDM. RESULTS: Both black and white patients were found to have a high prevalence of hypertension, obesity, low high density lipoprotein (HDL) cholesterol, low leisure-time physical activity levels, and an atherogenic dietary profile. Black males were more likely to have hypertension, reported a greater intake of dietary cholesterol, and had lower triglycerides, higher HDL cholesterol levels, a lower CHOL/HDL ratio, and a lower waist to hip ratio (WHR) than white males. Black females had higher mean arterial and diastolic blood pressures, had lower triglycerides, higher HDL cholesterol, a lower CHOL/HDL ratio, a higher subscapular/triceps ratio and lower reported leisure-time energy expenditure compared to white females. There were no racial differences found for obesity level. CONCLUSION: Our results indicate that racial differences in CHD risk factors exist among black and white patients with NIDDM. The complex genetic, sociocultural and environmental interactions involving CHD risk factors that contribute to the development of CHD may eventually provide clues to the etiology of the disease.

Aged↗
PubMed1996

Neural stimulation of Egr-1 messenger RNA expression in rat adrenal gland: possible relation to phenylethanolamine N-methyltransferase gene regulation.

Metrazole, which reflexively activates the splanchnic nerve to the adrenal medulla, was used to investigate the physiological role of Egr-1 in the neural regulation of phenylethanolamine N-methyltransferase (PNMT) gene transcription in the rat adrenal gland. A single dose of this drug (70 mg/kg s.c.) rapidly and transiently induced Egr-1 mRNA, with a maximum 22.0-fold increase at 30 min after treatment, followed by a 3.7-fold increase in PNMT mRNA at 8 hr. In contrast, cocaine (15 mg/kg i.p.), which activates the hypothalamic-pituitary-adrenal axis, increased Egr-1 mRNA only 3-fold at 30 min, although it elevated PNMT mRNA comparably. Consistent with their mechanisms of activation, cocaine increased corticosterone levels 7.7-fold at 30 min, whereas metrazole modestly elevated this endogenous corticosteroid 2.5-fold. The cholinergic agonists nicotine (2 mg/kg l.p.) and muscarine (0.1 mg/kg i.p.) also elevated Egr-1 mRNA, with a peak 12- to 15-fold increase being apparent at 30 min after treatment, followed by a 1.7-to 2.0-fold rise in PNMT mRNA at 8 hr. In vitro, metrazole did not increase Egr-1 mRNA above levels observed with carbachol alone (100 microM) in PC-12-derived RS1 cells pretreated with this cholinergic agonist. Finally, splanchnic denervation partially blocked the metrazole-induced rise in Egr-1 mRNA (50% control), while having no effect on cocaine-induced changes in Egr-1 mRNA. These results provide further support for the involvement of Egr-1 in the neural regulation of PNMT gene expression in the rat adrenal gland.

Adrenal Glands↗
PubMed1995

A novel low molecular weight ecdysiotropin in post-diapause, pre-hatch eggs of the gypsy moth, Lymantria dispar L. (Lepidoptera: Lymantriidae).

Extracts of post-diapause, pre-hatch eggs of the gypsy moth, Lymantria dispar L. were examined for prothoracicotropic hormone (PTTH)-like activity using an in vitro assay involving last-instar prothoracic glands (PGs). The eggs were extracted in water, eluted from a low-pressure C18-silica cartridge in 60% acetonitrile, and fractionated on a high-performance, size-exclusion column. The primary ecdysiotropic activity eluted with an estimated molecular weight of 2.1 kDa far below the 4-7 kDa size determined for the low molecular weight PTTHs (bombyxins). Dose-response analysis revealed that the maximum activation was reduced by 75% by organic solvent extraction, but the remaining activity retained the ability to maximally activate the PGs 10-fold in vitro. At least some of the ecdysiotropic activity in the post-diapause, pre-hatch egg is localized in the brain of the pharate larva, and this activity increases dramatically prior to hatch when eggs are incubated at 25 degrees C.

Animals↗
PubMed1995

Racial differences in the prevalence of microalbuminuria in hypertension.

One hundred nine patients with essential hypertension and without either diabetes mellitus or clinical proteinuria were examined to investigate possible racial differences in urinary albumin excretion rates. The black hypertensive patients were found to have significantly higher urinary albumin excretion rates compared with the white patients; in addition, a significantly greater proportion of the black patients than the white patients (32% v 14%) had microalbuminuria, defined as a urinary albumin excretion rate greater than 30 micrograms/min. These differences could not be explained by age, blood pressure, body mass index, glycosylated hemoglobin, serum creatinine, duration of hypertension, or type of hypertension treatment. Hypertensive renal failure occurs six to 18 times more frequently in blacks than in whites; to our knowledge, these data are the first to indicate that microalbuminuria may be more prevalent during the course of hypertension in black patients and thus may be an early marker for end-organ damage susceptibility among hypertensive patients.

Albuminuria↗
PubMed1995

Dietary intakes by levels of glycemic control for black and white adults with non-insulin dependent diabetes mellitus (NIDDM).

OBJECTIVES: The relationship between diet and glycemic control was examined among a racially mixed population of male and female adults with non-insulin dependent diabetes mellitus (NIDDM). METHODS: Data from 3-day dietary records and glycosylated hemoglobin (HbA1c) were analyzed for two-hundred eighty two patients of a Family Practice Ambulatory Care Unit and a community-based health center in Winston-Salem, North Carolina. Correlations were calculated for individual nutrients to determine their strength of association with glycemic control. Analyses by tertiles of HbA1c were also conducted for each race/gender group. Regression analysis was used to determine independent dietary predictors of HbA1c. RESULTS: For all subjects, energy, energy per kilogram of body weight, fat, carbohydrates saturated fat, and cholesterol were significantly correlated with HbA1c. Nutritional differences across tertile levels of HbA1c for all subjects were not significant. For black females, consumption of energy, protein and fat was significantly higher among upper tertile subjects compared to the lowest tertile; and intake of energy, protein, fat, and saturated fat was significantly correlated with HbA1c in this group. For black males, energy intake was highest among upper tertile subjects compared to those in the middle tertile, while energy per kilogram of body weight, and percent of calories from protein, were significantly correlated with HbA1c. For white males, energy intake expressed as a function of body weight was highest among subjects in the upper tertile and a significant positive correlation with HbA1c was observed. No relationship between nutritional intake and HbA1c was found among white females. Racial differences in nutrient intake were also compared for males and females in the upper tertile of HbA1c. Black females in the upper tertile consumed significantly more energy, protein, and significantly less dietary fiber per 1000 kilocalories. No significant differences were observed between black and white males in the upper tertile, although higher cholesterol consumption in black males compared to white males approached significance. Regression analysis revealed that total energy intake significantly predicted HbA1c for all subjects and all white subjects, while a similar observation was made for total fat intake among all black subjects and among black females. CONCLUSIONS: These findings confirm that diet, especially total energy, is an important contributor to glycemic control. Dietary fat is also associated with glycemic control among blacks, especially black females, who are especially prone to more dire health consequences of NIDDM. Strict monitoring of diet should lead to improved glycemic control and less mortality and morbidity in this population.

Adult↗
PubMed1995

Racial differences in psychosocial variables among adults with non-insulin-dependent diabetes mellitus.

To determine whether racial differences exist in psychosocial variables among patients with non-insulin-dependent diabetes mellitus (NIDDM), the authors administered a series of questionnaires to 211 Black and White patients of the Wake Forest Family Medicine ambulatory care unit and the Reynolds Health Center, a community health center. In general, Blacks in the study population had higher levels of external locus of control, higher levels of stress, and lower levels of family functioning compared with Whites. These differences may account partially for the disparity of diabetes control and the consequences of diabetes among Blacks. Health professionals may benefit from understanding and addressing these psychosocial variables and may be more successful in implementing intervention programs in this population by tailoring programs to the psychosocial orientation of their population.

Adaptation, Psychological↗
PubMed1995

Are learning objectives useful in evaluating medical school course and instructor performance?

We tested the hypothesis that learning objectives could be used to evaluate course and instructor effectiveness. Ninety-seven third-year medical students who had their surgical clerkship or their medical clerkship as their first clinical rotation were compared. The surgery clerks received 171 urologic learning objectives. Students taking the surgical clerkship had significantly higher postclerkship recognition of the learning objectives than did medical clerkship students. One year later, these students were again surveyed to determine whether they still knew the correct response to the learning objective. The follow-up survey showed that 50% of the students recognized objectives covered in five of the eight urology lectures, while the other lectures were not effective. Students who recognized the objective on the postclerkship evaluation were more likely to think the objective had been taught on this follow-up survey. These data suggest that learning objectives are useful for evaluating course and instructor effectiveness.

Adult↗
PubMed1995

Is the stroke belt disappearing? An analysis of racial, temporal, and age effects.

BACKGROUND AND PURPOSE: The stroke risk among white residents of the coastal plain of North Carolina, South Carolina, and Georgia (the "Stroke Belt") has been reported to be between 1.3 and 2.0 times the national average. In this study we examined (1) whether a similar excess risk exists for blacks in this region, (2) whether this regional excess stroke risk has decreased over time, and (3) whether the regional excess risk is consistent across ages from 45 to more than 85 years. METHODS: Using data from the Compressed Mortality File, we estimated the annual relative stroke mortality risk for black and white men and women in a region of 153 coastal plain counties and compared these rates to those for the remainder of the United States. RESULTS: The relative geographic excess risk of stroke death was similar for black residents and white residents of the Stroke Belt for both men and women. Despite the decline in stroke mortality, the relative increased risk of stroke death in the region has remained constant from 1968 to 1991; however, the pattern of excess risk across age differed significantly between race/sex groups. CONCLUSIONS: These data show that the Stroke Belt continues to exist for blacks and whites and for men and women. Although the specific causes of the Stroke Belt remain unknown, the public health impact is staggering, with a greater than 40% excess risk of stroke mortality and more than 1200 excess stroke deaths annually.

Age Factors↗
PubMed1994

An immunoglobulin switchlike sequence is linked with canine narcolepsy.

Canine narcolepsy is an animal model of the human disorder that is transmitted as a single autosomal recessive gene with full penetrance (canarc-1) in Dobermans and Labradors. In previous experiments, we have identified a very tight linkage marker for canarc-1. This marker, a 0.85-kb band cross reacting with a human mu-switch Heavy-Chain Immunoglobulin probe (maximum logarithm of odds [LOD] score Zmax = 10.8 at 0% recombination), has now been cloned and sequenced. The gene, composed of GC rich repeats, is 75% homologous to the human mu-switch gene and is similar in organization to immunoglobulin switch genes. Curiously, however, this mu-switchlike segment appears to be unlinked with other switchlike polymorphisms detected at high stringency with the human mu-switch probe. Because in most animal species all switch genes are located within 300-500 kb and show tight linkage in families, this result suggests two possible hypotheses: 1) Our 0.85 kb is a true immunoglobulin switch segment, but the map of the canine Variable Heavy-Chain loci is organized in unlinked clusters, or 2) our 0.85-kb segment is not an immunoglobulin switch segment and is located elsewhere in the genome in all species. We are now using chromosome walking and Yeast Artificial Chromosome Cloning techniques, together with corresponding studies in humans to identify the pathological gene.

Alleles↗