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PubMed2004

Trends in overweight among adolescents living in the poorest and richest regions of Brazil.

OBJECTIVES: We assessed changes in body mass index (BMI) among Brazilian adolescents. METHODS: In 1975, 1989, and 1997, we conducted household surveys of the weights and statures of a probabilistic sample of about 50,000 Brazilian adolescents aged 10 to 19 years. Weighted prevalences were calculated and an analysis was performed with the sample design taken into account. RESULTS: Adolescents of rich (southeast) and poor (northeast) regions showed a substantial increase in BMI. In the southeast, the prevalence of overweight, defined by international age- and gender-specific BMI cutoffs, for both genders reached 17% in 1997, whereas in the northeast, the prevalence tripled, reaching 5% among boys and 12% among girls. Older girls living in urban areas in the southeast showed a decrease in prevalence from 16% to 13% in the latter 2 surveys. For all boys and for young girls, the BMI values for the 85th percentile in 1997 were much higher than the 95th percentile values in 1975. CONCLUSIONS: BMI increased dramatically in Brazilian adolescents, mainly among boys; among older girls from the richest region, the prevalence of overweight is decreasing.

Adolescent↗
PubMedDate not supplied

A spatially explicit investigation of phosphorus sorption and related soil properties in two riparian wetlands.

Soils of riparian wetlands are highly effective at phosphorus (P) sorption. However, these soils exhibit extreme spatial variability across riparian zones. We used a spatially explicit sampling design in two riparian wetlands in North Carolina to better understand the relationships among P sorption, soil properties, and spatial variability. Our objectives were to quantify patterns of spatial variability of P sorption and related soil properties, and to determine which soil properties best explained the variability in P sorption after accounting for the effects of spatial autocorrelation. We measured bulk density, moisture, pH, soil organic matter (SOM), texture (percent clay, silt, and sand), oxalate-extractable aluminum (Al(ox)), iron (Fe(ox)), and the phosphorus sorption index (PSI). Due to differences in texture, Al(ox), and Fe(ox), the two sites had substantially different mean PSIs. At each site, we found considerable differences in the spatial variability of soil properties. For example, semivariance analysis and kriging illustrated that soil properties at Site 1 varied at smaller scales than those at Site 2. At both sites, after accounting for the effects of spatial autocorrelation and all other soil properties, we determined that Al(ox) had the highest Mantel correlation with PSI. We believe this geostatistic and Mantel approach is robust and could serve as a model for research on other biogeochemical processes such as denitrification.

Adsorption↗
PubMed2006

Population pharmacokinetics of itraconazole and its active metabolite hydroxy-itraconazole in paediatric cystic fibrosis and bone marrow transplant patients.

OBJECTIVE: The objective of the study was to characterise the population pharmacokinetic properties of itraconazole and its active metabolite hydroxy-itraconazole in a representative paediatric population of cystic fibrosis and bone marrow transplant (BMT) patients and to identify patient characteristics influencing the pharmacokinetics of itraconazole. The ultimate goals were to determine the relative bioavailability between the two oral formulations (capsules vs oral solution) and to optimise dosing regimens in these patients. METHODS: All paediatric patients with cystic fibrosis or patients undergoing BMT at The Royal Children's Hospital, Brisbane, QLD, Australia, who were prescribed oral itraconazole for the treatment of allergic bronchopulmonary aspergillosis (cystic fibrosis patients) or for prophylaxis of any fungal infection (BMT patients) were eligible for the study. Blood samples were taken from the recruited patients as per an empirical sampling design either during hospitalisation or during outpatient clinic visits. Itraconazole and hydroxy-itraconazole plasma concentrations were determined by a validated high-performance liquid chromatography assay with fluorometric detection. A nonlinear mixed-effect modelling approach using the NONMEM software to simultaneously describe the pharmacokinetics of itraconazole and its metabolite. RESULTS: A one-compartment model with first-order absorption described the itraconazole data, and the metabolism of the parent drug to hydroxy-itraconazole was described by a first-order rate constant. The metabolite data also showed one-compartment characteristics with linear elimination. For itraconazole the apparent clearance (CL(itraconazole)) was 35.5 L/hour, the apparent volume of distribution (V(d(itraconazole)) was 672 L, the absorption rate constant for the capsule formulation was 0.0901 h(-)(1) and for the oral solution formulation was 0.96 h(-1). The lag time was estimated to be 19.1 minutes and the relative bioavailability between capsules and oral solution (F(rel)) was 0.55. For the metabolite, volume of distribution, V(m)/(F . f(m)), and clearance, CL/(F . f(m)), were 10.6L and 5.28 L/h, respectively. The influence of total bodyweight was significant, added as a covariate on CL(itraconazole)/F and V(d(itraconazole))/F (standardised to a 70 kg person) using allometric three-quarter power scaling on CL(itraconazole)/F, which therefore reflected adult values. The unexplained between-subject variability (coefficient of variation %) was 68.7%, 75.8%, 73.4% and 61.1% for CL(itraconazole)/F, V(d)((itraconazole)())/F, CL(m)/(F . f(m)) and F(rel), respectively. The correlation between random effects of CL(itraconazole) and V(d(itraconazole)) was 0.69. CONCLUSION: The developed population pharmacokinetic model adequately described the pharmacokinetics of itraconazole and its active metabolite, hydroxy-itraconazole, in paediatric patients with either cystic fibrosis or undergoing BMT. More appropriate dosing schedules have been developed for the oral solution and the capsules to secure a minimum therapeutic trough plasma concentration of 0.5 mg/L for these patients.

Administration, Oral↗
PubMed1989

Exercise and fitness for persons with disabilities.

Over the past decade greater attention has been focused on the role of exercise and fitness for persons with disabilities. Increased involvement in exercise programmes, competitive sports and fitness activities has led to further inquiry into the broader concepts of performance, prevention of further deterioration of a given disability, maintenance for activities of daily living, and overall well-being. This paper reviews the literature on 3 categories of disabilities, mental retardation, mental illness and selected physical disabilities, in order to determine the role of exercise and fitness programmes in each. Despite problems in research design, sampling procedures, instrument validity, and delineation of fitness components, there is growing support for the premise that physical exercise has a role to play in breaking the debilitative cycle. Although the research indicates that physical activity can serve as a potential non-pharmacological adjunct therapy for persons with physical disabilities, there is still a need for well-controlled studies to quantify the individualization of exercise programming.

Persons with Disabilities↗
PubMed2006

Possible stimuli for strength and power adaptation : acute metabolic responses.

The metabolic response to resistance exercise, in particular lactic acid or lactate, has a marked influence upon the muscular environment, which may enhance the training stimulus (e.g. motor unit activation, hormones or muscle damage) and thereby contribute to strength and power adaptation. Hypertrophy schemes have resulted in greater lactate responses (%) than neuronal and dynamic power schemes, suggesting possible metabolic-mediated changes in muscle growth. Factors such as age, sex, training experience and nutrition may also influence the lactate responses to resistance exercise and thereafter, muscular adaptation. Although the importance of the mechanical and hormonal stimulus to strength and power adaptation is well recognised, the contribution of the metabolic stimulus is largely unknown. Relatively few studies for example, have examined metabolic change across neuronal and dynamic power schemes, and not withstanding the fact that those mechanisms underpinning muscular adaptation, in relation to the metabolic stimulus, remain highly speculative. Inconsistent findings and methodological limitations within research (e.g. programme design, sampling period, number of samples) make interpretation further difficult. We contend that strength and power research needs to investigate those metabolic mechanisms likely to contribute to weight-training adaptation. Further research is also needed to examine the metabolic responses to different loading schemes, as well as interactions across age, sex and training status, so our understanding of how to optimise strength and power development is improved.

Biotransformation↗
PubMed1990

Particle size reduction during initial mastication of forages by dairy cattle.

Four experiments were conducted with dairy cattle to determine the effects of initial feed particle size and moisture content on particle size of ingested masticates. Three mature Holstein cows were used in either latin square or Youden square designs. Samples of masticated and ingested boli were collected at the cardiac opening through a ruminal fistula between 0 and 5, 5 and 10 and 10 and 15 min after meal initiation. In Exp. 1, masticate log mean particle sizes (LMPS) (ln microns, log normal distribution) were 3.50, 3.53 and 3.50 for corn silage, fine-chopped alfalfa haylage and coarse-chopped alfalfa haylage, respectively. In Exp. 2, boli LMPS for ground, chopped and long alfalfa hay were 3.11, 3.76 and 4.09, respectively. Boli LMPS in Exp. 3 for ground, chopped and long timothy hay were 2.93, 3.12 and 3.03, respectively. Exp. 4 compared the effect of addition of water to produce 30%, 47%, 64% and 82% DM in chopped alfalfa hay. Boli LMPS were 3.66, 3.56, 3.64 and 3.68 for the respective alfalfa hay DM contents. Feed LMPS was not reduced during mastication in Exp. 4, nor were there differences in LMPS due to time after feeding. Boli LMPS was affected by feed particle size of alfalfa hay, but there was no effect of feed particle size on masticate particle size in timothy hay. The magnitude of particle size reduction during mastication appears to be dependent on forage type and is not dependent totally on initial feed particle size and DM content of forages.

Animal Feed↗
PubMed1994

Long-term effects of adolescent drug use in the Israeli middle class.

This is a self-report study of a purposive sample of 111 middle-class Israelis in their 30s. The sample, designed to overrepresent adolescent drug experience, included 53 subjects (47.7%) reporting having tried illicit drugs during adolescence (epidemiological data indicate approximately 7% percent adolescent drug use in Israel). None of the users was apprehended. Comparing the users with the nonusers on variables indicating adult conformity, adjustment, and subjective well-being revealed no significant difference between the two groups.

Adaptation, Psychological↗
PubMed1999

Life satisfaction and health-related quality of life (SF-36) of middle-aged men and women.

OBJECTIVES: To investigate life satisfaction and health-related quality of life (SF-36) in a general population sample of middle-aged women and men. The effects of menopausal status and hormone replacement therapy (HRT) use upon life satisfaction and health-related quality of life (HrQOL) were also examined for the female sample. DESIGN: All men and women aged 49-55 years from the age/sex register of a large general practice in London were contacted and asked to complete a questionnaire about their health. SUBJECTS: A total of 103 women (55%) and 86 men (40%) participated; of the women, 15% were premenopausal, 68% peri- or postmenopausal and 17% taking HRT. RESULTS: Women and men reported similar levels of HrQOL, life satisfaction and general health, although women reported more physical problems (SF-36). The significant predictors of HrQOL were serious illness, employment and marital status, but HRT use and menopausal status were not significantly associated with life satisfaction nor HrQOL (for women). CONCLUSIONS: Gender differences in health and HrQOL may be less apparent during mid-life, although there were some subtle differences between men and women in reported health concerns and reasons given for (dis)satisfaction with their lives.

Body Mass Index↗
PubMed1996

Enhanced intake and production of cows offered ensiled alfalfa with higher neutral detergent fiber digestibility.

The objective of this study was to determine the effect of forage fiber digestibility as part of a total mixed diet on intake and production of cows with intakes that were likely limited by rumen fill, using treatments that were not confounded by fiber source, concentrate, or ratio of forage to concentrate. Two alfalfa silages with similar NDF concentrations (40%) but different NDF digestibilities (40 vs. 45% after 24 h of in vitro fermentation) were harvested, mixed with concentrate to achieve diets containing 35% NDF, and offered to 12 multiparous cows (13 DIM) in a two-period balanced crossover design. Samples taken during silage feeding revealed that diets differed in both NDF digestibility (3 percentage units) and NDF content (1.8 percentage units), making interpretation of results difficult. Nonetheless, milk production (36.3 vs. 38.2 kg/d) and DMI (19.4 vs. 20.4 kg/d) were significantly higher with the higher NDF digestibility diet. Apparent in vivo DM and NDF digestibilities, total rumen VFA after feeding, and molar percentage of propionate were also higher with this diet. Equal NDF intake between diets suggested that higher DMI was due to the lower NDF content in the more digestible NDF diet. Higher NDF digestibility might also increase DMI; further experimentation is necessary with larger unconfounded differences in fiber digestibility at the time of feeding.

Animals↗
PubMed2006

Self-medication with antimicrobial drugs in Europe.

We surveyed the populations of 19 European countries to compare the prevalence of antimicrobial drug self-medication in the previous 12 months and intended self-medication and storage and to identify the associated demographic characteristics. By using a multistage sampling design, 1,000-3,000 adults in each country were randomly selected. The prevalence of actual self-medication varied from 1 to 210 per 1,000 and intended self-medication from 73 to 449 per 1,000; both rates were high in eastern and southern Europe and low in northern and western Europe. The most common reasons for self-medication were throat symptoms (e.g., dry, inflamed, red, or sore throat, inflamed tonsils, tonsil pain). The main medication sources were pharmacies and medication leftover from previous prescriptions. Younger age, higher education, and presence of a chronic disease were associated with higher rates of self-medication. Attempts to reduce inappropriate self-medication should target prescribers, pharmacists, and the general public.

Anti-Bacterial Agents↗
PubMed2002

Epidemiological findings of hepatitis B infection based on 1998 National Health and Nutrition Survey in Korea.

The purpose of this study was to investigate the epidemiological characteristics of hepatitis B virus (HBV) infection in Korea based on the 1998 National Health and Nutrition Survey. Study subjects consisted of 9,771 aged 10 yr or over, who were selected from across Korea using a stratified multistage probability sampling design. The prevalence of hepatitis B surface antigen (HBsAg) was compared by age, sex, residency, household income, education, family history, family size, and frequency of eating out. The prevalence of HBsAg was 5.1% (95% confidence interval (CI): 4.5-5.7) in males and 4.1% (95% CI: 3.6-4.6) in females with a low prevalence in those under 20 yr old. Generally, HBsAg seropositivity by administrative area was similar with the exception of Jeju province. HBsAg seropositivity of Jeju island was approximately three times higher in both men and women, as compared with the national average. HBsAg seropositivity by socioeconomic status unexpectedly showed a very consistent positive association in both gender. Comparing HBsAg seropositivity by the frequency of eating out, in both gender, the more frequent they ate out, the higher it was. Our study suggested that there might be another transmission route of HBV, which is possibly related to diet.

Adolescent↗
PubMed2005

Urban and rural differences in the prevalence of gender and age specific obesity and related health behaviors in Korea.

The objective of this study was to discuss the residential difference in gender and age specific prevalence of obesity by body mass index (BMI) and obesity related health behaviors in the Republic of Korea. A total of nationally representative 2,583 men and 3,087 women (age: 20-64 yr) was used as subjects from 1998 National Health and Nutrition Survey. All statistics were calculated using SUDAAN to consider a stratified multistage probability sampling design. The prevalence of obesity (BMI> or =25) was significantly different by age, gender and residential areas. Although younger men aged 20-49 yr did not show a residential difference in the prevalence of obesity, men aged 50-64 yr showed differences, highest in big cities and lowest in rural areas. However, in women, a higher prevalence was observed in rural areas compared to urban areas in the younger age group (20-49 yr), but not in the older age group. Residential differences of obesity related health behaviors existed mostly in the older population, but not in the younger population. The urban-rural differences demonstrate the various stages of behavioral transition that Korea is currently undergoing. Therefore, different strategies considering those factors are needed to manage obesity problems in Korea.

Adult↗
PubMed2006

Relationship between metabolic syndrome and familial history of hypertension/stroke, diabetes, and cardiovascular disease.

This research analyzes the prevalence of metabolic syndrome (MS) in Korea and examines how the presence of a familial history of diseases related to MS, such as hypertension/stroke, cardiovascular disease, and diabetes, affect the development of MS in Koreans. The prevalence of MS and its components, as defined by the Nation-al Cholesterol Education Program Adult Treatment Panel guidelines, were evaluated in nationally representative samples of non-institutionalized civilian Koreans. This analysis is based on the 2001 Korea National Health and Nutrition Examination Survey, which used a stratified multistage probability sampling design. The final study included 5,742 adults who had completed the necessary health examinations and met the diagnosis of MS. The prevalence of MS was 25.5% in men and 28.7% in women. Odds ratio for MS among men with a familial history of hypertension/stroke was higher than that among men who did not have this history. The OR for MS among women with a familial history of hypertension/stroke or diabetes was higher than that among women who had no familial history of these diseases. These results show that familial history of hypertension/stroke and diabetes was significantly related to the presence of MS in both young men and women.

Adult↗
PubMed2003

Effect of the Antarctic environment on hormone levels and mood of Chinese expeditioners.

BACKGROUND: Serum thyroid hormones, plasma catecholamines and mood were examined in 10 male members of the 16th Chinese Antarctic Expedition who spent the 2000 austral winter at Great Wall Station. STUDY DESIGN: Samples were taken prior to deployment to Antarctica (December, 1999) and upon return to China 54 weeks later (December, 2000). The expeditioners also completed the Profile of Mood States (POMS) each month over an 8-month period (April through November, 2000). RESULTS: There was a significant decrease in levels of serum total thyroxine (p < 0.01) and plasma epinephrine (p < 0.05), and a significant increase in serum TSH (p < 0.01). With the exception of a significant decline in level of vigor (p = 0.008), there were no significant changes in mood throughout the expedition. Low levels of pre- and post-deployment total triiodothyronine and high levels of TSH were significantly associated with high levels of tension-anxiety, depression, anger, confusion, and total mood disturbance at the beginning and end of winter. High levels of TSH were also significantly associated with high levels of fatigue (p < 0.001), while low levels of total thyroxine were significantly associated with high levels of tension-anxiety (p < 0.001), depression (p < 0.05), and total mood disturbance (p < 0.05). Low levels of dopamine were significantly associated with high levels of tension-anxiety (p < 0.05). An increase in anger during the austral winter was significantly associated with an increase in adrenaline during the expedition (p < 0.05). CONCLUSION: The increase in TSH, and its association with mood, is consistent with the polar T3 syndrome, while the absence of changes in free triiodothyronine and thyroxine may reflect characteristics of the environment, or racial/ethnic differences in psychophysiological, or socio-cultural adaptation to circumpolar environments.

Adaptation, Physiological↗
PubMed2004

The preliminary assessment of the Social Transition in the North dataset: a comparison of STN survey and enumeration data for selected Northwest Alaskan communities.

OBJECTIVE: This study compared the results from STN survey data with a mailback health study of the same communities to assess the reliability of the STN data. STUDY DESIGN. Sample characteristics and respondes to health questions were compared through secondary data analysis. Data from the STN sample was compared to an enumeration study for the same or similar questions, including demographic characteristics and health status indicators, were compared. METHODS: The STN study used the sample of 715 households in 18 Alaskan and Russian Far East communities to obtain data on the demographic transition, epidemiological transition and domestic transition of residents in northern communities. A study of the health and human service needs was conducted in Northwest Alaska using a mailback health questionnaire within a few years of the STN study. RESULTS: Both data sets appear to be taken from similar populations. Responses to health questions show marked similarities. CONCLUSION: The comparison strongly suggests that the STN data is representative of northern Alaska communities surveyed and can be a valuable source of reliable data on the health and welfare of northern communities. The data on the self-reported prevalence of health conditions may not be useful at the community level.

Alaska↗
PubMedDate not supplied

Spatial analysis of within-population microsatellite variability reveals restricted gene flow in the Pacific golden chanterelle (Cantharellus formosus).

We examined the within-population genetic structure of the Pacific golden chanterelle (Cantharellus formosus) in a 50 y old forest stand dominated by Douglas-fir (Pseudotsuga menziesii) and western hemlock (Tsuga heterophylla) with spatial autocorrelation analysis. We tested the null hypothesis that multilocus genotypes possessed by chanterelle genets were randomly distributed within the study area. Fruit bodies from 203 C. formosus genets were collected from a 50 ha study plot. One hundred six unique multilocus genotypes were identified after scoring these collections at five microsatellite loci. Statistically significant positive spatial autocorrelation was detected indicating the presence of fine-scale genetic structure within the area. Repeated autocorrelation analyses with varied minimum distance classes (50-500 m) detected positive spatial genetic structure up to 400 m. Therefore nonrandom evolutionary processes (e.g., isolation by distance) can cause fine-scale genetic structure in C. formosus. The implications of this research for future broad-scale population studies of this species are that population samples should be separated by at least 400 m to be considered statistically independent. Sampling designs that account for fine-scale genetic structure will better characterize heterogeneity distributed across the landscape by avoiding the effects of pseudo replication.

Basidiomycota↗
PubMed1995

Atrial natriuretic peptide and blood pressure in a population-based sample.

OBJECTIVE: To assess the relationship of plasma atrial natriuretic peptide (ANP) levels with blood pressure levels and the occurrence of hypertension in a large population-based sample. DESIGN: We performed a cross-sectional study of the relationship between ANP levels and blood pressure levels, diagnosis of hypertension, and family history of hypertension in Caucasians from Rochester, Minnesota. MATERIAL AND METHODS: Plasma ANP and blood pressure levels were measured in 1,338 Caucasian subjects who were members of 301 three-generation families from the population of Rochester. Hypertension was defined as systolic blood pressure of 140 mm Hg or more or diastolic blood pressure of 90 mm Hg or more. Each subject in the parental generation was categorized as having zero, one, or two parents with hypertension. Analyses were done separately for each generation and gender stratum. RESULTS: Within gender and generation strata, we noted no consistent pattern of positive or negative correlation of plasma ANP levels with systolic blood pressure, diastolic blood pressure, or heart rate. Within the grandparental generation, mean plasma ANP levels did not differ between those with normal blood pressure and those with hypertension. In the parental generation, mean plasma ANP levels did not differ between subjects with zero, one, or two parents with hypertension. CONCLUSION: In Caucasians, interindividual differences in plasma ANP levels are not associated with interindividual differences in blood pressure levels, the diagnosis of hypertension, or family history of hypertension.

Adolescent↗
PubMed1993

HTLV-I among Northern Territory blood donors.

OBJECTIVE: Human T-lymphotropic virus type I (HTLV-I) is known to be endemic among Northern Territory (NT) Aborigines, therefore evidence was sought of HTLV-I infection in NT blood donors. DESIGN: Samples were screened for HTLV-I antibodies using the Serodia HTLV-I particle-agglutination assay. Repeatedly reactive sera were tested by western blot. Viro- logical and molecular investigations were also performed. SERA: Aliquots from all 11,121 blood donations collected between June 1991 and August 1992. RESULTS: Four (0.036% of total) blood donations, each from different donors, were repeatedly reactive by particle-agglutination assay. One (0.009%) sample, from a 52-year-old non-Aboriginal man with no verified risk factors, was confirmed as HTLV-I seropositive by western blot. A viral isolate and a 431 base pair polymerase chain reaction product from the env gene were obtained from a culture of his peripheral blood mononuclear cells. Sequencing of the polymerase chain reaction product demonstrates that this isolate is a prototype strain and not the variant identified among Aborigines. The remaining three repeatedly reactive donors, including the positive donor's wife, were western blot indeterminate. CONCLUSIONS: There is a low prevalence of HTLV-I carriage among blood donors in the NT, and presumably in other States. However, most repeatedly reactive donations prove to be western blot indeterminate, therefore additional tests are required to detect or exclude HTLV-I infection. Although universal screening of donations would virtually eliminate HTLV-I transmission by transfusion, it has disadvantages, including financial cost.

Adult↗