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Biomedical subjects

M Q Wang

Publications and source records attributed to M Q Wang.

At least 37 records · Page 2Linked to original sources

School dropouts' attitudes and beliefs about smoking.

The purpose of this study was to examine the association of beliefs and attitude related to smoking and smoking behavior among school dropouts in a national sample (weighted N = 492,352). The self-reported smoking rate for school dropouts was 58.3%. Those who were most positive about smoking (such as smoking helps people reduce stress and relax, reduce boredom) were more likely to be smokers (p < .05). Smoking programs targeting this population should provide coping skills and an environment with options for relaxing, managing stress, and safe weight control.

Adolescent↗

Lactate production in response to maximal and submaximal StairMaster PT4000 and treadmill exercise.

BACKGROUND: The purpose of this study was to measure the amount of lactate produced, as an indication of fatigue, in response to maximal and submaximal stairstepper (SM) and treadmill (TM) exercise. METHODS: Thirty volunteers (15 males, mean age 23 yrs; 15 females, mean age 22 yrs) completed maximal and submaximal SM and TM protocols on four separate visits to the laboratory to determine maximal oxygen consumption (VO2max), and blood lactate concentrations. Maximal TM testing consisted of the Bruce protocol, while the maximal SM protocol involved progressing in increments of 2 levels every 2 minutes. Eight minutes of submaximal TM and SM exercise was performed at an intensity of 65% of VO2max, as measured during maximal TM and SM testing. Fifty microliters of blood was collected via fingerprick of the index finger prior to, and immediately post maximal and submaximal TM and SM exercise, and during minutes 3, 5, and 7 of active recovery. Red blood cells were lysed and analyzed immediately using the YSI # 1500 Sport lactate analyzer. RESULTS: TM-VO2max, was significantly higher for both, males and females, compared to SM-VO2max. Repeated measured analyses of variance revealed significantly higher blood lactate levels during the same relative submaximal workloads for SM compared to TM exercise. CONCLUSIONS: These findings suggest that an increased lactate production during submaximal SM exercise may result in early fatigue and, thereby, limit maximal performance on the SM.

Adult↗

The anti-angiogenic agent fumagillin covalently binds and inhibits the methionine aminopeptidase, MetAP-2.

The inhibition of new blood vessel formation (angiogenesis) is an effective means of limiting both the size and metastasis of solid tumors. The leading anti-angiogenic compound, TNP-470, has proven to be effective in in vitro and in animal model studies, and is currently being tested in phase III antitumor clinical trials. Despite many detailed pharmacological studies, little is known of the molecular mode of action of TNP-470. Using a derivative of the TNP-470 parent compound, the fungal metabolite, fumagillin, we have purified a mammalian protein that is selectively and covalently bound by this natural product. This fumagillin binding protein was found to be a metalloprotease, methionine aminopeptidase (MetAP-2), that is highly conserved between human and Saccharomyces cerevisiae. In the absence of MetAP-1, a distantly related methionine aminopeptidase, MetAP-2 function is essential for vegetative growth in yeast. We demonstrate that fumagillin selectively inhibits the S. cerevisiae MetAP-2 protein in vivo. The binding is highly specific as judged by the failure of fumagillin to inhibit MetAP-1 in vivo. Hence, these results identify MetAP-2 as an important target of study in the analysis of the potent biological activities of fumagillin.

Amino Acid Sequence↗

B cell stimulating activity of seaweed extracts.

The activity of seaweed extracts on murine and human lymphocytes was studied in vitro. The extracts of some kind of seaweed, such as Hizikia fusiformis and Meristotheca papulosa, stimulated normal mouse spleen cells to proliferate. The responder cells are B cells, because the response was depleted by the treatment of spleen cells with anti-immunoglobulin (Ig) antibody and complement and being passed through a nylon wool column. This response is not due to lipopolysaccharide (LPS) contamination, because seaweed extracts can stimulate spleen cells of C3H/HeJ mice which are LPS low responders. Seaweed extracts also enhanced Ig production by B cells and tumor necrosis factor (TNF) production by macrophages. Furthermore, seaweed extracts stimulated human lymphocytes to proliferate. All these B cell stimulating activities of seaweed extracts associated with glycoproteins whose molecular weights resided in 100 kD. These results suggest that seaweed extracts have stimulating activity on B cells and macrophages and this ability could be clinically for the modulation of immune responses.

Animals↗

Immunomodulating activity of Chinese medicinal herbs and Oldenlandia diffusa in particular.

The effect of eight different Chinese medicinal herbs (CMHs) on lymphocytes was studied in vitro using murine spleen cells. Among the studied eight CMHs, Astragalus membranaceus and Oldenlandia diffusa markedly stimulated murine spleen cells to proliferate. The responder cells for CMHs were B cells, because the response was depleted by the treatment of spleen cells with anti-immunoglobulin (i.g.) antibody and complement and after purification by nylon wool column. This response was not due to contamination by lipopolysaccharide (LPS), because CMHs could stimulate C3H/HeJ spleen cells which are low responders to LPS. CMHs enhanced the production of Ig. CMHs also enhanced the induction of allo-antigen specific cytotoxic T lymphocytes. However, CMHs had no effect on natural killer cells. Furthermore, CMHs stimulated macrophages to produce interleukin-6 and tumor necrosis factor. The electroelution of the proteins from SDS-PAGE gel showed that the active components of Oldenlandia diffusa had an apparent molecular weight of 90-200 kD and were sensitive to pronase E and NaIO4 treatment, suggesting glycoproteins in nature. These results suggest that CMHs have immunomodulating activity in vitro and this activity could be used clinically for the modulation of immune responses.

Adjuvants, Immunologic↗

Sociobehavioral influences on smoking initiation of Hispanic adolescents.

PURPOSE: To study the sociobehavioral influences on smoking initiation of Hispanic adolescents over a 3-year period using a national sample. METHODS: Hispanic adolescents (N = 385), ages 15-22 years, from the 1989 and 1993 Teenage Attitudes and Practices Surveys (TAPS I and II), were selected for analyses. Data collected included measures of smoking initiation and attitudes, beliefs toward smoking of the adolescent, and smoking status of family and peers. RESULTS: At the 3-year follow up, 43.4% of nonsmokers at TAPS I had initiated smoking. Risk factors associated with initiating smoking were having male and/or female friends who smoked, and positive attitudes and beliefs towards smoking. Parental and sibling smoking status had little effect on adolescent smoking status. CONCLUSIONS: The peer influence on Hispanic adolescent smoking is consistent with previous research on Caucasian and African-American adolescents. The formation of attitudes and beliefs toward smoking in this population warrants further examination given the influence of attitudes and beliefs on smoking initiation in this study.

Adolescent↗

Social influence on southern adolescents' smoking transition: a retrospective study.

The purpose of this study was to examine social factors that predicted adolescent smoking transition to more advanced stages of smoking behavior during a 3-year span. A national cohort sample of adolescents (N = 2,099) who participated in the 1989 and 1993 Teenage Attitudes and Practices Survey (TAPS I and TAPS II, respectively) was used for this study. The information obtained from this survey included measurements of smoking behavior and a series of factors related to smoking models in the respondents' social environment, such as smoking behavior of parents, siblings, and best friends. Results showed that the smoking behavior of an adolescent's best male friend was consistently associated with transition from nonsmoking to regular smoking and from experimental smoking to regular smoking. The most surprising finding was that the study showed no relationship between social influence and transition from nonsmoking to experimental smoking.

Adolescent↗

Depressive symptoms as correlates of polydrug use for blacks in a high-risk community.

BACKGROUND: This study examined the relationship between depressive symptoms and polydrug use (alcohol, marijuana, and cocaine) among blacks in a high-risk community. METHODS: A street sample (N = 570) from four high-risk communities in Birmingham, Alabama, was collected through personal interviews. Interviewers asked respondents about their drug use behavior during the past 30 days, as well as about their depressive symptoms during the past week. RESULTS: Odds ratios and logistic regressions, adjusted for age and sex, were used to assess the relationship between depressive symptoms and drug and polydrug use (drug use involving cocaine). Results showed that depressive symptoms are significantly associated with polydrug use. However, depressive symptoms were not associated with alcohol use or with the combination of alcohol and marijuana use. CONCLUSIONS: Depressive symptoms are related to polydrug use involving cocaine, though the causal relationship is uncertain. Previous reports on depressive symptoms and alcohol or marijuana may be inconclusive.

Adult↗

Association of depressive symptoms and school adolescents' smoking: a cross-lagged analysis.

This study examined the association of depressive symptoms of adolescents and their smoking behavior. A national cohort sample of school adolescents (N = 5,855) who participated in the 1989 and 1993 Teenage Attitudes and Practices Survey was obtained. The information from this survey included measures of smoking behavior and a series of factors related to depressive symptoms during a 3-yr. span. A cross-lagged analysis with Kendall tau b correlations was used. Judging from the magnitude of the cross-lagged correlations, the direction of causation cannot be ascertained. Rather, a reciprocal relationship between depression and smoking may be suggested.

Adolescent↗

The association between parental smoking and the diet quality of low-income children.

OBJECTIVE: To assess the association between parental smoking and the diet quality of children residing in low-income housholds in the United States. MTHODS: Data from 515 low-income children (less than or equal to 185% of the poverty line), ages 2 to 17, who participated in the 1989 and 1990 United States Department of Agriculture Continuing Survey of Food Intakes of Individuals were examined. Diet quality was assessed by examining the average daily amount of nutrients consumed per 1000 kcal for protein, fiber, and 14 essential vitamins and minerals as well as total energy, percent of energy from total fat and saturated fat, and cholesterol and sodium intakes using the 3-day average of one 24-hour recall and 2 days of diet records. Parental smoking was categorized as four levels (nonsmoker; 1 to 10, 11 to 20, and more than 20) on the basis of the average number of cigarettes smoked per day by the sample child's parents. Analysis of covariance examined differences in the children's nutrient intake among the four smoking categories while controling for race, mother's age and occupation, child age, and sex. RESULTS: Low-income children with parents who smoked (n = 235) were more likely to be white (P <.001), had younger mothers (P <.05) and were more likely to have mothers employed in blue-collar occupations (P <.001) than children whose parents were nonsmokers (N = 280). Children whose parents smoked more than 20 cigarettes per day had a higher level of energy from saturated fat, and children whose parents smoked 11 to 20 cigarettes per day had the highest cholesterol intakes in comparison with the rest of the sample. Parental smoking was also related to total fiber intake per 1000 kcal, with children of smokers having lower fiber intakes than children of nonsmokers. CONCLUSIONS: On average, low-income children of smokers had a poorer diet quality than low-income children of nonsmokers, thus increasing their future risk of chronic disease.

Adolescent↗

Dysfunction of immune system and induction of autoantibodies to liver antigens by neonatal thymectomy in mice.

We examined the development of autoantibodies to liver proteins and hepatitis in BALB/c mice thymectomized 2 days after birth and attempted to characterized the immune function of these mice. Autoantibodies to crude liver proteins detected by ELISA were found in 21 (84%) of 25 mice thymectomized 2 days after birth. In these mice, sera of 11 animals showed reactivity with both liver specific proteins (LSP) and the second fraction of crude liver proteins; sera of 3 mice showed reactivity with only the second fraction but sera showed reactivity with only LSP. By Western-immunoblotting, sera of BALB/c mice which showed high autoantibody level to liver proteins detected a strong band around 150kD in the second fraction of crude liver proteins. Still more, hepatic inflammation; mononuclear cell infiltration in the portal area, was induced in mice with apparently high autoantibody level to crude liver proteins. These results in BALB/c mice corresponded with our previous reports which employed C3H/HeN mice. Next, we examined immune functions of mice thymectomized 2 days after birth. In thymectomized mice, the proportion of Thy-1, L3T4 and Lyt-2 positive cells (T cells) decreased and the proportion of B220 positive cells (B cells) increased. The proliferative response of lymph nodes lymphocytes cultured with mitomycin C-treated syngeneic spleen cells was lower, and the total IgG level in the sera was higher when compared with control normal mice. Anti-nuclear antibody (ANA) also appeared in the sera of thymectomized mice 2 days after birth. All these results suggest that the dysfunction of T cell and polyclonal activation of B cell were induced in neonatally thymectomized mice and resulted in the production of ANA and autoantibodies to liver proteins.

Animals↗

Family and peer influences on smoking behavior among American adolescents: an age trend.

PURPOSE: To study the age trend of family and peer influence on adolescent smoking behavior using a national sample. METHODS: Adolescents (N = 6,900), ages 14 through 18 years, from the 1988-89 Teenage Attitudes and Practices Survey, were selected for analyses. Data collected included measures for smoking status of the adolescent and their family and peers. RESULTS: Peer influence, such as the smoking status of best male/female friends, proved to be the most significant and consistent predictor across all ages, while parental influence had little effect on adolescent smoking status. Gender-specific effects were noted in the peer influence of adolescent smoking. CONCLUSIONS: The peer influence on adolescent smoking, across ages 14 through 18 years, confirmed previous literature. However, no differential effect of family and peer influence on adolescent smoking was evident.

Adolescent↗

B cell mitogenic activity of Toxocara canis adult worm antigen.

The effect of Toxocara (T.) canis antigen (TcAg) on lymphocytes was studied in vitro using normal murine spleen cells and human peripheral blood lymphocytes. TcAg prepared from adult worms stimulated murine spleen cells to proliferate at concentrations of 1-125 micrograms/ml. The responder cells TcAg are B cells, because the response was depleted by the treatment of spleen cells with anti-immunoglobulin (Ig) antibody and complement and after separation on a nylon wool column. This response was not due to the contamination of lipopolysaccharide (LPS), because TcAg could stimulate C3H/HeJ spleen cells which are low responders to LPS. Not only the proliferative response but also polyclonal IgG and IgE production were stimulated with TcAg. TcAg also stimulated macrophages to produce interleukin-1 and could stimulate human B cells. These results suggest that TcAg is a potent B cell mitogen and this activity may be relevant to the alteration of immunological functions in hosts infected with T. canis.

Animals↗

The value of ten common exercise tolerance test measures in predicting coronary disease in symptomatic females.

The diagnostic contribution of ten common exercise tolerance test (ETT) measures compared with coronary angiography was studied in 62 symptomatic females (mean age = 53 +/- 9 years). Logistic regression revealed that maximal ST-segment depression, the percent of predicted maximal heart rate achieved, and test chest pain all contributed unique predictive information and formed a model generating probabilities for coronary disease (CAD). Using a predicted probability for the presence of CAD of 0.50 as a cutpoint, test accuracy was markedly improved (sensitivity = 73%, specificity = 94%, and overall correct classification rate = 90%) over the standard ST response. We conclude that multivariate analysis using these three easily assessed ETT measures provides superior discrimination between symptomatic women with and without CAD when compared to changes in the ST-segment alone.

Coronary Angiography↗

The acute effect of moderate alcohol consumption on cardiovascular responses in women.

OBJECTIVE: The purpose of this study was to assess the effects of moderate dose alcohol consumption on human metabolic and cardiovascular responses during submaximal exercise. METHOD: Ten female subjects participated in two experimental conditions: (1) an alcohol session where the subjects ingested 0.625 g per kg body weight of 80-proof ethyl alcohol (0.25 g/kg of 100% ethanol), and (2) a placebo session. In each session, the subjects exercised on a stationary bicycle at 70% predicted maximum heart rate (HR) for 30 minutes. HR, blood pressure (BP) and oxygen consumption (VO2) were measured at the baseline and at 10, 20 and 30 minute intervals during exercise. Blood lactic acid (BLA) was measured at the baseline and at the end of exercise. RESULTS: Repeated analysis of variance and subsequent comparisons showed that the alcohol session had significantly higher scores for HR, BP, VO2 and BLA than the placebo session (p < .05). CONCLUSIONS: These results suggest that during submaximal work, acute moderate alcohol consumption may interfere with aerobic energy metabolism, thus increasing the demand placed upon the cardiovascular system.

Adult↗

Relationship of alcohol consumption and recreational boating in Beaufort County, North Carolina.

The purpose of this study was to examine the relationship between alcohol use and recreational boating activities. Two hundred eleven (n = 211) boaters were surveyed at three boating access locations in Beaufort County, North Carolina. The survey questionnaire consisted of fifteen questions designed to obtain information on boat operators and their use of alcoholic beverages while engaging in boating activities. Prevalence and amount of alcohol use while boating were significantly associated (p < .05) with the type of activity engaged in. Among those boaters who had received some type of boating safety education, a higher prevalence of alcohol use while boating was observed. The prevalence and amount of alcohol use while boating were found to be significantly (p < .05) associated with the location (public versus private) of boating access. In light of the findings, it is apparent that boating alcohol education and legislation for the North Carolina boating population need assessment and revision. The implications of the findings could have far-reaching effects upon education and prevention among the recreational boating population, particularly if further research in this area supports these finding.

Adult↗

Associations between academic performance of division 1 college athletes and their perceptions of the effects of anabolic steroids.

Data on the relationship between academic performance (grade point average) of college athletes and their perceptions of the effects of anabolic steroids on their sport and their performance were collected from Division 1 athletes (N = 1,638) representing 12 varsity sports chosen from five universities nationwide. The response rate was 74%. Analysis yielded differences between athletes with high and low GPAs in perceptions of the effects of anabolic steroids. The lower the GPA, the less likely the athletes were to believe that anabolic steroids are a threat to health, are a problem in their sport, and are addictive. Also, they were more likely to believe that anabolic steroids enhance performance.

Achievement↗