Early menarche and blood pressure in adulthood: systematic review and meta-analysis.

Background: It has been reported that early menarche is associated with high blood pressure and hypertension. However, some studies have failed to observe such association. We carried out a systematic review and meta-analysis on the association of early menarche with hypertension and high blood pressure in adulthood. Methods: PUBMED, SciELO, Scopus and LILACS databases were searched. Studies that evaluated the association of early menarche with hypertension or high blood pressure, among women aged 20 years or more were included. Random effects models were used to pool the estimates. Meta-regression was used to evaluate the contribution of different co-variables to heterogeneity. Results: We identified 17 studies with 18 estimates on the association of early menarche with hypertension and high blood pressure. The odds of hypertension/high blood pressure was higher among women with early menarche [pooled (OR):1.25; 95% confidence interval (CI): 1.17-1.34; P < 0.001]. In the meta-regression analysis, studies evaluating 1500 subjects or more had a higher pooled OR [1.27; 95%CI (1.19;1.36)] than those with less participants. Although funnel plots showed some asymmetry, Egger tests were not statistically significant. Therefore, it is unlikely that the observed association was to publication bias. Conclusions: Early menarche is associated with hypertension among adult woman.

The prevalence and severity of dental pain in 14-15 year old Brazilian schoolchildren.

OBJECTIVE: To assess the prevalence and severity of dental pain and associated factors in Brazilian schoolchildren. METHODS: The study was a cross-sectional survey conducted in Recife, Brazil. The data were collected through questionnaires, personal interviews and clinical dental examinations of a random sample of 14-15 years old schoolchildren. The prevalence of dental pain and its characteristics were recorded using standard measures of pain. Dental caries, dental trauma and dental plaque were assessed using WHO criteria. Multiple logistic and ordinal polytomous regression were used to assess which factors were associated with the dental pain outcomes. RESULTS: 1,052 individuals participated in the study. The prevalence of reported toothache in schoolchildren in the last six months was 33.6% (31.1-36.8, 95% CI). The fully adjusted regression models showed a significant relationship between lower social class, later birth order, failure at school and attendance at the dentist only when in trouble with both the prevalence and severity of dental pain. The major predictor of the prevalence and severity of pain was pattern of dental attendance (p<0.001). CONCLUSIONS: The prevalence of toothache in 14-15 years old schoolchildren was high. The major predictor of the prevalence and severity of pain was the pattern of dental attendance.

Reduced lighting does not improve medical outcomes in very low birth weight infants.

OBJECTIVE: To objectively assess the effect of light reduction as an isolated environmental intervention on neonatal morbidity. STUDY DESIGN: Randomized multicenter trial. Neonates < 1251 g birth weight and < 31 weeks gestational age were randomly assigned to receive goggles or to a control group. Goggles that reduced visible light by 97% were placed within 24 hours of birth and remained in use until 31 weeks postmenstrual age or for a minimum of 4 weeks. RESULTS: Four hundred nine infants were enrolled, and outcome data are reported for 359 surviving infants. There were no significant differences between the groups in weight gain, duration of oxygen therapy, mechanical ventilation, or hospital stay either in the unadjusted analyses or in the analyses adjusted for birth weight, gestational age, race, sex, and inborn (born in study hospital) status. There was no difference between the groups in the incidence of intracranial hemorrhage. CONCLUSIONS: This randomized trial of continuous light reduction in the first few weeks of life for very low birth weight infants showed no effect on medical outcomes.

Adolescents' sense of coherence, oral health status, and oral health-related behaviours.

OBJECTIVE: To investigate the relationship between sense of coherence (SOC) and oral health. It was hypothesised that subjects with better oral health status and better oral health-related behaviours have higher levels of SOC. METHODS: A cross-sectional study was conducted in Goiânia-GO, Middle-West Brazil, on a sample of 664 15-year-olds randomly selected from schools. Data were collected through questionnaires, the short version of Antonovsky's SOC Scale (13-item) and clinical dental examinations. Multiple logistic regression and polytomous ordered regression were used in the data analysis. Two sets of outcome variables were selected for the analyses: oral health status (dental caries, oral cleanliness, and periodontal disease), and oral health-related behaviours (frequency of sugar intake, toothbrushing frequency, and pattern of dental attendance). RESULTS: Adolescents' SOC was associated with their caries experience in anterior teeth (OR=0.81 for 10 units increase in SOC scale; 95% CI=0.66-0.98), but the relationship did not remain significant after controlling for other factors. Adolescents with higher SOC were less likely to visit the dentist mainly when in trouble, compared with those with lower SOC (OR=0.83, 95% CI=0.71-0.98), or equivalently more likely to visit for mainly check-ups. Other measures of oral health status and behaviours were not significantly associated with SOC. CONCLUSION: SOC was identified as a psychosocial determinant of adolescents' oral health-related behaviour, particularly affecting their pattern of dental attendance.

Neural tube defects among Mexican Americans living on the US-Mexico border: effects of folic acid and dietary folate.

Populations of Mexican descent have high occurrences of neural tube defects (NTDs). A recent study suggested that folic acid supplements may not protect these populations from NTDs. In a case-control study, the authors investigated the role of folic acid and dietary folate intake in NTD risk among Mexican Americans living along the Texas-Mexico border. From January 1995 to February 1999, 148 Mexican-American women with NTD-affected pregnancies and 158 women with normal live births were interviewed in person about use of vitamin supplements and dietary intakes during a 6-month periconceptional period (from 3 months before conception to 3 months after conception). Daily preconceptional consumption of vitamin supplements containing folic acid was 2.5% in control women and 2.0% in case women (odds ratio = 0.77; 95% confidence interval (CI): 0.19, 3.22). With adjustment for maternal age, education, obesity, and previous stillbirth or miscarriage, the risk estimate was essentially null (odds ratio = 1.12; 95% CI: 0.22, 5.78). Combined folic acid intake from diet and supplements showed only a modest risk reduction for intakes of > or = 1.0 mg per day (adjusted odds ratio = 0.73; 95% CI: 0.31, 1.72). The fact that the primary folic acid exposure was in the form of dietary polyglutamates rather than the more easily absorbed supplemental monoglutamates may explain an apparent decreased effect in this population.

N(2) Fixation by Azospirillum brasilense and Its Incorporation into Host Setaria italica.

Growth and nitrogen fixation were followed during the life cycle of Setaria italica (foxtail millet) inoculated with Azospirillum brasilense in controlled-environment growth chambers. The plants were fertilized at seeding with a limiting amount of combined nitrogen and maintained with an N-free mineral solution. During maturation of the plants, substantial nitrogenase activity, measured by acetylene reduction, developed in the rhizosphere, with total fixation estimated to be equivalent to 20% of the N in the inoculated plants. The peak of this activity coincided with depletion of soluble nitrogen from the system, which in turn was reflected by a sharp decrease in the nitrate reductase activity of the leaves. A. brasilense was found in association with the root populations at 8 x 10 cells per gram of dry weight. An increase in shoot growth occurred at this time, but no significant increase in total plant nitrogen could be demonstrated. N(2) enrichment experiments confirmed that fixation was occurring, but only about 5% of the nitrogen fixed by A. brasilense was incorporated into the plants within 3 weeks. There was thus no evidence of direct bacterium-to-plant transport of fixed nitrogen, but rather a slow transfer suggesting the gradual death of bacteria and subsequent mineralization of their nitrogen, at least under growth-room conditions.

Enhanced Mineral Uptake by Zea mays and Sorghum bicolor Roots Inoculated with Azospirillum brasilense.

Inoculation of corn (Zea mays) seeds with Azospirillum brasilense strain Cd or Sp 7 significantly enhanced (30 to 50% over controls) the uptake of NO(3), K, and H(2)PO(4) into 3- to 4-day- and 2-week-old root segments. No gross changes in root morphology were observed; altered cell arrangement in the outer four or five layers of the cortex was seen in photomicrographs of cross sections of inoculated corn roots. The surface activity involved in ion uptake probably increased, as shown by the darker staining by methylene blue of the affected area. Shoot dry weight increased 20 to 30% in inoculated plants after 3 weeks, presumably by enhancement of mineral uptake. Corn and sorghum plants grown to maturity on limiting nutrients in the greenhouse showed improved growth from inoculation approaching that of plants grown on normal nutrient concentrations. Enhanced ion uptake may be a significant factor in the crop yield enhancement reported for Azospirillum inoculation.