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The association between parental alcohol-related behaviors and children's drinking.

Past literature has established an association between children's alcohol-related behaviors and parents' use of and attitudes toward alcohol. However, most studies tend to measure parental use and attitudes through proxy, i.e. children's perception. It is not clear the extent to which actual parental use and attitudes influence children's alcohol behaviors. The current study directly used parents' reports on alcohol use and attitudes toward alcohol and examined their impact on children's alcohol use. Based on a three-stage random sampling design, 642 dyads of parents and children (ages 15-18) were interviewed by telephone in New York State. Study variables include parental alcohol use, children's alcohol use, parental attitudes toward underage drinking and parent-child interaction. While parental use and attitudes do not seem to significantly affect children's alcohol use, the extent to which parents prohibit children from using alcohol at home tends to reduce children's alcohol involvement. In addition, the greater the amount of time spent with alcohol-using parents, the more likely the children are to use alcohol. Findings suggest that, while parents' alcohol use influences children's alcohol use through extensive interaction, parental control of underage alcohol use in the household appears to reduce children's involvement in underage alcohol use.

Adolescent↗

Antioxidant supplementation in vitro improves boar sperm motility and mitochondrial membrane potential after cryopreservation of different fractions of the ejaculate.

Antioxidant supplementation during cooling was assayed to improve the motility of frozen-thawed (FT) boar spermatozoa from two different fractions of the ejaculate, the first component of the sperm-rich fraction (Fraction I) and the rest of the bulk ejaculate (Fraction II). Using a split-sample design, addition of two different concentrations (100 and 200 microMl(-1)) of the water-soluble Vitamin E analogue Trolox (6-hydroxy -2,5,7,8-tetramethylchroman -2-carboxylic acid) was evaluated for an effect on sperm motility (measured both subjectively and by means of a computer assisted motility assessment (CASA)), and on mitochondrial membrane potential using flow cytometry after cell-loading with JC-1. The effect of the Vitamin E analogue was clearly dose-dependent and varied with the fraction of the ejaculate considered. Motility was significantly higher in Trolox-treated spermatozoa (200 microm), from either ejaculate fraction, albeit the effect was more evident in spermatozoa from Fraction II (P<0.05) for any Trolox-concentration. Antioxidant supplementation resulted, also dose-dependent, in a higher number of spermatozoa showing high mitochondrial activity as assessed by the JC-1 staining, in both ejaculate fractions. In the present trial, exogenous Trolox positively affected post-thaw sperm viability (as motility and mitochondrial membrane potential) in both fractions of the ejaculate. The magnitude of the effect appeared, however, to be dependent of the fraction of the ejaculate considered.

Animals↗

Differences in locomotor activity across the lifespan of Drosophila melanogaster.

The identification of differential patterns of change across the lifespan in quantitative traits is of abiding interest in the biological and gerontological research communities. These differential phenotypic patterns in complex systems illuminate developmental processes and form the foundation for the identification of putative biomarkers of aging. The goal of the present study was to explore changes in locomotor activity through the lifespan of Drosophila melanogaster. A replicated serial cross-sectional sampling design was used to test activity in five genetically independent inbred strains at 7, 14, 21, 28, 35, and 42 days of age. Differences were observed in activity level across ages and strains, suggesting that patterns of activity throughout the lifespan of D. melanogaster are influenced by genetic factors. Observed sex differences in change in activity level indicate that the aging processes may proceed differently in males and females.

Animals↗

Depression as a predictor for coronary heart disease. a review and meta-analysis.

OBJECTIVE: To review and quantify the impact of depression on the development of coronary heart disease (CHD) in initially healthy subjects. DATA SOURCES: Cohort studies on depression and CHD were searched in MEDLINE (1966-2000) and PSYCHINFO (1887-2000), bibliographies, expert consultation, and personal reference files. DATA SELECTION: Cohort studies with clinical depression or depressive mood as the exposure, and myocardial infarction or coronary death as the outcome. DATA EXTRACTION: Information on study design, sample size and characteristics, assessment of depression, outcome, number of cases, crude and most-adjusted relative risks, and variables used in multivariate adjustments were abstracted. DATA SYNTHESIS: Eleven studies met the inclusion criteria. The overall relative risk [RR] for the development of CHD in depressed subjects was 1.64 (95% confidence interval [CI]=1.29-2.08, p<0.001). A sensitivity analysis showed that clinical depression (RR=2.69, 95% CI=1.63-4.43, p<0.001) was a stronger predictor than depressive mood (RR=1.49, 95% CI=1.16-1.92, p=0.02). CONCLUSION: It is concluded that depression predicts the development of CHD in initially healthy people. The stronger effect size for clinical depression compared to depressive mood points out that there might be a dose-response relationship between depression and CHD. Implications of the findings for a broader bio-psycho-social framework are discussed.

Adolescent↗

A new generation of serum anti-HIV antibody immunocapture assay for saliva testing.

BACKGROUND: Epidemiological studies need easier tools to evaluate HIV prevalence, particularly in high-risk groups under difficult field conditions. Testing saliva antibody with accurate immunoassay could serve as an alternative to serum testing. OBJECTIVES: To evaluate performances on saliva of a novel commercially available assay for anti-HIV antibody. STUDY DESIGN: Samples of saliva from 530 patients were tested for the presence of HIV antibodies with a third generation commercially available serum-screening kit and the use of a sample diluent adapted to saliva. RESULTS: Compared with serum sampling the sensitivity and specificity of oral sampling were respectively, 100 and 99.8%. CONCLUSION: The ICE HIV-1.0.2 assay used on saliva could be an efficient and non-invasive epidemiological tool for HIV testing.

Adult↗

What is antibiotic resistance and how can we measure it?

Antibiotic resistance is being found with increasing frequency in both pathogenic and commensal bacteria of humans and animals. Quantifying resistance within and between bacterial and host populations presents scientists with complex challenges in terms of laboratory methodologies and sampling design. Here, we discuss, from an epidemiological perspective, how antibiotic resistance can be defined and measured and the limitations of current approaches.

Anti-Bacterial Agents↗

Overview of randomized trials in high risk breast cancer patients treated with adjuvant systemic therapy with or without postmastectomy irradiation.

Postmastectomy irradiation has been analyzed in several randomized trials, usually without the presence of systemic therapy. Overview analysis of these studies has shown that, although postmastectomy irradiation generally reduces the locoregional recurrence rate by a factor of 3, this is not transferred into a general long-term survival benefit. Recently, a clinically relevant survival gain from adjuvant radiotherapy has been shown in high-risk premenopausal patients also treated with adjuvant chemotherapy. There are now 11 published trials, including more than 6000 patients, in which the effect of postmastectomy radiotherapy has been evaluated in the presence of adjuvant systemic therapy. This article reviews the available data from these trials, as well as problems in their design, sample size, inclusion criteria, quality, and extent of treatments, and length of follow-up time.

Breast Neoplasms↗

Prevalence of health-related behaviors among alternative high school students as compared with students attending regular high schools.

PURPOSE: To provide national data on health-risk behaviors of students attending alternative high schools and compare the prevalence of these risk behaviors with data from the 1997 national Youth Risk Behavior Survey. METHODS: The national Youth Risk Behavior Survey uses a three-stage cluster sampling design. Data were collected from 8918 students in alternative high schools in 1998 (ALT-YRBS) and 16,262 students in regular high schools in 1997 (YRBS). The health-risk behaviors addressed include behaviors that contribute to unintentional injuries and violence, tobacco use, alcohol and other drug use, sexual behaviors, unhealthy dietary behaviors, and physical inactivity. A weighing factor was applied to each student record to adjust for nonresponse and varying probabilities of selection. SUDAAN was used to compute 95% confidence intervals, which were considered significant if the 95% confidence intervals did not overlap. RESULTS: Students attending alternative high schools were at significantly greater risk than students in regular high schools for violence-related injury; suicide; human immunodeficiency virus infection or other sexually transmitted diseases; pregnancy; and development of chronic disease related to tobacco use, unhealthy dieting practices, and lack of vigorous activity. CONCLUSIONS: Many students in alternative high schools are at risk for both acute and chronic health problems. Because these youth are still in a school setting, alternative high schools are in a unique position to provide programs to help decrease the prevalence of risk-taking behaviors.

Adolescent↗

Historical relationships among Neotropical lowland forest areas of endemism as determined by mitochondrial DNA sequence variation within the Wedge-billed Woodcreeper (Aves: Dendrocolaptidae: Glyphorynchus spirurus).

Studies of the distribution of South American taxa have identified several areas of endemism that may have contributed to the historical diversification of the region. We constructed a phylogeny of Glyphorynchus spirurus (Aves: Dendrocolaptidae) populations using mtDNA sequence data from portions of cytochrome b, NADH dehydrogenase subunit II (ND2), and complete NADH dehydrogenase subunit III (ND3). Using this phylogeny we evaluate five previous hypotheses of area-relationships, two based on phylogenetic studies of morphological characters in birds and three based on parsimony analysis of endemism in birds and primates. Maximum likelihood and maximum parsimony analyses recovered two phylogenetic hypotheses that differed in the placement of one of the areas. Within each of the areas of endemism, the two analyses support the same clades. Neither of the phylogenetic hypotheses for Glyphorynchus exactly matches any of the five previous hypotheses of area-relationships, although ambiguous support exists for one of them. Five areas-Central America, Inambari, Napo, Pará, and Rondônia-are supported as composites with component taxa having phylogenetic affinities with more than one area. Data reported here also indicate high levels of sequence divergence within Glyphorynchus. Genetic breaks within Glyphorynchus are only partially congruent with subspecific taxonomy. The regional sampling design used makes this study the largest scale genetic assay of a widespread Neotropical avian taxon published to date.

Central America↗

Statistical methods for analyzing repeated measures.

Repeated measurements arise frequently in biomedical research. In many situations, the scientific question of interest concerns finding differences in the measurements between groups. This question is frequently addressed by using analysis of variance-type methods that fail to incorporate information regarding the repeated sampling design of the experiment. In this paper, we provide an introduction to nonstatisticians of two approaches for analyzing such data. The procedures can be performed by using available software. These methods are illustrated on data from a preclinical study conducted by ZymoGenetics.

Angiotensin-Converting Enzyme Inhibitors↗

Changes in surface levels of mercury, silver, tin, and copper of dental amalgam treated with carbamide peroxide and hydrogen peroxide in vitro.

OBJECTIVES: The effect of 10% carbamide peroxide or 10% hydrogen peroxide on the surface levels of mercury, silver, tin, and copper of amalgam fillings was tested in vitro with scanning electron microscopy and energy dispersive spectrometric microanalysis. STUDY DESIGN: Samples of amalgam were treated for 14 and 28 days with either 10% carbamide peroxide or 10% hydrogen peroxide solutions and compared with phosphate buffer controls. RESULTS: A significant increase in mercury levels occurred after treatment with carbamide peroxide for 14 days (p < 0.01) and 28 days (p < 0.001) and after treatment with hydrogen peroxide for 28 days (p < 0.001). A significant increase in silver levels occurred after treatment with carbamide peroxide for 14 days (p < 0.05) and 28 days (p < 0.01) and subsequent to treatment with hydrogen peroxide for 14 days (p < 0.05) and 28 days (p < 0.001). A significant reduction in tin levels occurred after treatment with hydrogen peroxide for 14 days (p < 0.01) and 28 days (p < 0.001), and after treatment with carbamide peroxide for 28 days (p < 0.01). A significant reduction in copper levels was found after treatment with carbamide peroxide for 14 days (p < 0.05). CONCLUSIONS: It appears that prolonged treatment with bleaching agents may cause microstructural changes in amalgam surfaces, possibly increasing exposure of patients to toxic byproducts.

Carbamide Peroxide↗

Bacterial adherence to bleached surfaces of composite resin in vitro.

OBJECTIVE: The effect of bleaching agents on bacterial adherence to polished surfaces of composite resin restorations was assessed in vitro. STUDY DESIGN: Samples of light-curing composite resins were treated with either 10% carbamide peroxide or 10% hydrogen peroxide for 1, 3, or 7 days. Bacterial adherence of Streptococcus mutans, Streptococcus sobrinus, and Actinomyces viscosus to the treated resin samples was analyzed and compared with adherence to nonbleached controls. RESULTS: A 10% solution of carbamide peroxide caused a significant increase in surface adherence of Streptococcus mutans and Streptococcus sobrinus after 3 days (P < .01). A 10% solution of hydrogen peroxide caused a significant increase in surface adherence of Streptococcus mutans and Streptococcus sobrinus after 3 and 7 days (P < .01). A decrease in adherence of Actinomyces viscosus was found after treatment with 10% hydrogen peroxide for 7 days (P < .05). CONCLUSIONS: It appears that bleaching agents may affect adherence of certain cariogenic microorganisms to the outer surfaces of composite resin restorations.

Actinomyces viscosus↗

Basic fibroblast growth factor (bFGF) in saliva and oral mucosa in patients with oral lichen planus: preliminary observations.

OBJECTIVE: Basic fibroblast growth factor (bFGF) is important for wound healing and tissue repair. This study measures the concentration of bFGF in oral lichen planus (OLP) affected mucosa and in the saliva of patients with OLP. STUDY DESIGN: Samples of saliva, OLP-affected mucosa, and clinically healthy mucosa were obtained from 11 patients. Control samples were obtained from healthy volunteers. The bFGF content of tissue samples and saliva was examined by ELISA. RESULTS: The mean bFGF concentration in saliva from OLP patients was 5.9 pg/mL, SD 2.9, compared with 0.3 pg/mL, SD 0.3, in the control group, (P>.01). The bFGF content in the OLP tissue was 90.6 microg/mg protein, SD 39.5, in clinically normal mucosa from OLP individuals it was 46.2 microg/mg protein, SD 12.0 (P=.02), and in the control group 46.2 microg/mg protein, SD 11.5 (P>.01). CONCLUSION: OLP-affected mucosa contained significant more bFGF than nonaffected mucosa in OLP and healthy mucosa in control group. There is no difference between nonaffected mucosa in OLP and control group. Saliva in OLP patients contained more bFGF than saliva in control patients.

Adult↗

Plasma carnitine levels of pregnant adolescents in labor.

STUDY OBJECTIVE: To determine the concentration of plasma carnitine (total, free, and acylcarnitine) during the delivery of uncomplicated pregnancies of adolescent women. To investigate the relationship between maternal and neonatal levels of carnitine and to compare these carnitine levels between pregnant and nonpregnant adolescents. DESIGN: Samples of maternal and umbilical blood were taken at the time of delivery and examined for the determination of the carnitine-total, free, and acylcarnitine-concentration by the use of an enzymatic-radioisotope method. Twenty-two cases of uncomplicated adolescent pregnancies with a normal labor and without perinatal complications were examined. The plasma level of carnitine was also examined in 17 healthy nonpregnant adolescent women, which constituted the control group. RESULTS: The concentrations of plasma carnitine in adolescent pregnancies at the time of delivery were calculated at 19.6 +/- 2.15 microMol/L (total), 12.62 +/- 1.31 microMol/L (free), and 6.98 +/- 1.55 microMol/L (acylcarnitine). The corresponding mean values in umbilical plasma were 30.31 +/- 2.06 microMol/L, 22.39 +/- 1.64 microMol/L, and 7.92 +/-.96 mucroMol/L. There is a statistically significant difference between the mean values in maternal and umbilical plasma (P <.0001 for total and free carnitine and P <.012 for acylcarnitine). The correlations between adolescent pregnant women and their infants as regards total, free, and acylcarnitine were 0.137, 0.018, and 0.33, respectively. Neither of these parameters was statistically significant. The corresponding mean values of carnitine in nonpregnant adolescent women were statistically significantly higher than in adolescent pregnant women (total carnitine: 41.61 +/- 3.09 microMol/L, free: 31.39 +/- 2.81 microMol/L, acylcarnitine: 10.22 +/- 1.88 microMol/L, P <.0001). CONCLUSIONS: The concentration of plasma carnitine at the end of adolescent pregnancy is low compared to the levels of umbilical carnitine at birth and that found in nonpregnant adolescent women. It may not have an obvious impact on the utilization of fatty acids in an uncomplicated full-term pregnancy; however, it suggests the potential risk for neonatal fatty-acid oxidation in a preterm or complicated pregnancy.

Adolescent↗

Seroepidemiology of Hantavirus in the Philippines.

OBJECTIVE: This study was undertaken to determine the seroepidemiology of Hantavirus infection in the Philippines. METHODS: This is a cross-sectional study done in asymptomatic volunteers from various communities in the Philippines selected by a stratified multistage sampling design. Antibody to Hantavirus was detected by particle agglutination (PA) test using Hantadia high-density particle agglutination (HDPA) reagent kit. RESULTS: The prevalence of positive Hantavirus antibody among 461 subjects was the same in both males (6.1%) and females (6.1%) in rural (7.6%), urban (5.6%), and urban poor (5.1%) populations. CONCLUSIONS: The prevalence of Hantavirus infection in the Filipino population is comparable to that seen in other developing countries. The HDPA can be conveniently used as a rapid tool to detect the Hantavirus antibody for seroepidemiologic and diagnostic purposes.

Adult↗

The effectiveness of community-based visual screening and utility of adjunctive diagnostic aids in the early detection of oral cancer.

A systematic review of community-based oral cancer screening programmes published between 1966 and March 2002 was undertaken. Data relating to study design, sampling and characteristics of the study group, interventions, and reported outcomes and diagnostic value of visual screening or adjunctive diagnostic aids were abstracted from 36 articles meeting inclusion and exclusion criteria. From these reports, there is insufficient evidence to demonstrate the effectiveness of community-based oral cancer visual screening in enhancing the early detection of oral cancer, due to small effect size. While the evidence is fair to support use of toluidine blue as an aid in diagnosis of oral cancer, there is insufficient evidence to determine whether the use of this or other adjunctive techniques will increase the detection of oral malignancies in community screening programmes. Targeted clinical examination of high-risk individuals may be more effective than mass screening in facilitating early detection of oral cancers.

Community Health Services↗

Detection of HSV-2 in genital ulcers from STD patients in Dar es Salaam, Tanzania.

BACKGROUND: Genital ulcer disease (GUD) is common in many developing countries. Several reports indicate that there is an association with HIV infection. Analysis by polymerase chain reaction (PCR) has demonstrated that the ulcers are frequently caused by herpes simplex type 2 (HSV-2), although HSV-1 is becoming increasingly important in many parts of the world. Comparable studies have not been performed in Tanzania. OBJECTIVES: To determine the prevalence of HSV-2 and HSV-1 in genital ulcers in Dar es Salaam, Tanzania and determine their possible association with HIV infection. STUDY DESIGN: Samples were collected from 70 consecutive patients with GUD attending a clinic for sexually transmitted diseases. Specimens from ulcers were analysed by PCR for the presence of HSV-2 and HSV-1, and sera were examined for antibodies against HSV-2 and HIV. RESULTS AND DISCUSSION: HSV-2 DNA was detected in 64% of the specimens from ulcers while HSV-1 DNA was not found in any of them. Antibodies to HSV-2 and HIV were detected in 79.7 and 42% of the patients' sera, respectively. Although there was a significant positive association between HIV and HSV-2 seropositivity, HSV-2 DNA in genital ulcers was not more prevalent among HIV seropositive than among HIV seronegative individuals. CONCLUSION: The prevalence of HSV-2 antibodies among Tanzanian patients with genital ulcers is very high, and HSV-2 is detected in most of the ulcers. There is an association between infections with HIV and HSV-2, but the relationship is not clear.

Adult↗

Serum cytokine profiles associated with clinical presentation in Vietnamese infected with hepatitis B virus.

BACKGROUND/OBJECTIVES: An ineffective cytokine response is thought to be one of the reasons for the failure to suppress hepatitis B virus (HBV) replication and to eliminate the virus. We investigated the serum levels of interleukin (IL)-6, IL-10, IL-12, and interferon (IFN)-gamma in HBV-infected Vietnamese patients to determine whether they were related to the outcome of HBV infection. STUDY DESIGN: Samples from a total of 154 HBV-infected patients with well-characterised clinical profiles and 56 healthy controls were assessed. RESULTS: Serum IL-6 levels, which were inversely correlated with transaminase levels, were highest in patients with liver cirrhosis (LC) and hepatocellular carcinoma (HCC) and lowest in those with either asymptomatic (ASYM), acute or chronic HBV, and thus, represented the best marker of HBV-related clinical progression. Compared with the healthy control group, serum IL-12 was uniformly elevated in all HBV-infected patients apart from those with ASYM infections, implying no impairment of production of this cytokine in HBV-infected individuals. Serum IL-10 and IFN-gamma levels, however, were uniformly low and showed no association with clinical presentation. Cytokine profiles were not influenced by the presence of hepatitis B e antigen (HbeAg). CONCLUSIONS: Serum IL-6 and IL-12 but not IL-10 and IFN-gamma are associated with the clinical presentation in HBV-infected Vietnamese patients.

Adult↗