Patterns of circulating hepatitis B surface antigen variants among vaccinated children born to hepatitis B surface antigen carrier and non-carrier mothers

Hepatitis B virus (HBV) variants that possessed missense mutation within the neutralization epitope of the major S antigen as defined by amino acid residues (aa#) 124–147, termed the a determinant variants, were identified through a population-based serosurvey of 2,305 children of the vaccinated birth cohorts born after 1986. Data on the 678 nucleotides encoding the S antigen of HBV were available for 75 HBV strains that were collected from 63 vaccinated children and 12 unvaccinated or incompletely vaccinated children, and 21 HBV strains from 25 unvaccinated adults. Among the diverse patterns of one to three amino acid substitutions within the a determinant, 145-Arg occurred most frequently (5/14); other variants were: 126-Ala, 127-Thr, 126-Ser/131-Asn/133-Thr, 129-His, 129-Arg, 123-Asn/131-Ile, 133-Leu, 141-Glu, and 141-Arg/144-Ala. Only one of these variants occurred in the 16 hepatitis B surface antigen (HBsAg)-carrier children born to HBsAg-negative mothers, whereas 12 of these variants occurred in the 20 (50%) children born to HBsAg-positive mothers. In addition, early administration of HBV vaccine within the noenatal period increased the likelihood of the emergence of these variants to 64.7% (11/17). Five of the 21 (23.8%) unvaccinated HBsAg-carrier adults harbored the a determinant variants possessing mutations within aa# 125–136, i.e. the putative first loop formed by the cysteine disulfide bonds. Vaccinated children were likely to harbor HBV variants possessing mutations involving altered charge of side chains and/or its hydrophobicity of amino acid residues within the putative second loop between aa#140 and 146. Our data suggest that emergence of these HBV S gene mutants in the phase of HBV vaccination program would be most common among populations in whom perinatal/vertical transmission of HBV is most common, i.e. southeast Asian and the Taiwanese.     

Abdominal Obesity and Ethnic Differences in Diabetes Awareness,Treatment, and Glycemic Control

Objective: To compare racial/ethnic differences in diabetes awareness, treatment, and glycemic control between non-Hispanic white, non-Hispanic black, and Hispanic Americans. We also determined the impact of abdominal obesity on racial/ethnic differences in diabetes awareness, treatment, and glycemic control between these population groups. Research Methods and Procedures: Third National Health and Nutrition Examination Survey (NHANES III) data were utilized for this study. Diabetes awareness was defined as acknowledging diabetic status. Diabetes treatment was defined as current use of anti-diabetic medications, good glycemic control as HbA_1c < 8%, and abdominal obesity as waist circumference larger than expected. The impacts of abdominal obesity on racial/ethnic differences in diabetes awareness, treatment, and glycemic control were assessed using logistic regression analyses. Adjustments were made for age, education, smoking, alcohol intake, and health insurance. Results: Rates of diabetes awareness in whites, blacks, and Hispanics suffering from abdominal obesity were ∼74%, 30%, and 21% in men and 77%, 32%, and 19% in women, respectively. Rates of diabetes treatment were 70%, 23%, and 14% in men and 57%, 45%, and 23% in women, respectively. In men, rates of glycemic control were 64%, 40%, and 30%, and in women, they were 62%, 51%, and 27%, respectively. Abdominal obesity was associated with decreased diabetes awareness and glycemic control in women. Discussion: Subjects with abdominal obesity were found to have poorer glycemic controls compared to those without abdominal obesity. Because diabetes prevalences were partially explained by racial/ethnic differences in diabetes awareness, treatment, and glycemic control, there is a need to craft diabetes awareness, treatment, and control programs along racial/ethnic origins.     

Physical Activity and the Metabolic Syndrome in a Tri-ethnic Sample of Women

Objective: To determine the association of moderate-intensity physical activity (PA), vigorous-intensity PA, and maximal treadmill duration with the metabolic syndrome among African-American (n = 49), Native-American (n = 46), and white (n = 51) women (ages, 40 to 83 years), enrolled in the Cross-Cultural Activity Participation Study. Research Methods and Procedures: The metabolic syndrome was defined as three or more of the following risk factors: waist circumference >88 cm, blood pressure ≥130/85 mm Hg, fasting glucose ≥110 mg/dL, hypertriglyceridemia (≥150 mg/dL), and high-density lipoprotein-cholesterol <50 mg/dL. PA was determined from detailed PA records that included all PA performed during two consecutive 4-day periods. Maximal treadmill duration was determined from a graded exercise test. Women were categorized into quartiles of moderate-intensity PA, vigorous-intensity PA, and maximal treadmill duration. Multiple logistic regression was used to estimate odds ratios of the metabolic syndrome as a function of the four PA categories, adjusted for age, ethnicity, study site, menopausal status, and use of hormone-replacement therapy. Results: The adjusted odds ratio for the metabolic syndrome was 0.18 (95% confidence interval, 0.33 to 0.90) for women in the highest category of moderate-intensity PA compared with women in the lowest category (p = 0.01 for trend). Similar associations were observed for the metabolic syndrome with vigorous-intensity PA (p = 0.01 for trend) and maximal treadmill duration (p = 0.0004 for trend). Discussion: Higher levels of moderate and vigorous-intensity PA and greater maximal treadmill duration were inversely associated with the metabolic syndrome among an ethnically diverse sample of women.     

Summary of the 2000 Surgeon General's Listening Session: Toward a National Action Plan on Overweight and Obesity

Objective: To provide insight into discussions at the Surgeon General's Listening Session, “Toward a National Action Plan on Overweight and Obesity,” and to complement The Surgeon General's Call to Action to Prevent and Decrease Overweight and Obesity. Research Methods and Procedures: On December 7 and 8, 2000, representatives from federal, state, academic, and private sectors attended the Surgeon General's Listening Session and were given an opportunity to recommend what to include in a national plan to address overweight and obesity. The public was invited to comment during a corresponding public comment period. The Surgeon General's Listening Session was also broadcast on the Internet, allowing others to view the deliberations live or access the archived files. Significant discussion points from the Listening Session have been reviewed by representatives of the federal agencies and are the basis of this complementary document. Results: Examples of issues, strategies, and barriers to change are discussed within five thematic areas: schools, health care, family and community, worksite, and media. Suggested cooperative or collaborative actions for preventing and decreasing overweight and obesity are described. An annotated list of some programmatic partnerships is included. Discussion: The Surgeon General's Listening Session provided an opportunity for representatives from family and community groups, schools, the media, the health-care environment, and worksites to become partners and to unite around the common goal of preventing and decreasing overweight and obesity. The combination of approaches from these perspectives offers a rich resource of opportunity to combat the public health epidemic of overweight and obesity.