Manganese exposure and association with hormone imbalance in children living near a ferro-manganese alloy plant.

It has been suggested that manganese (Mn) plays a fundamental role in the reproductive system through interference with the regulation of the secretion of hormones related to puberty. The objective of this study was to evaluate the environmental exposure to Mn and its effects on the endocrine regulation of hormones related to puberty in school-aged children living near a ferro-manganese alloy plant. Toenails, occipital hair, and blood samples were collected from 225 children, between 7 and 12 years of age, in four elementary schools in Simões Filho, Bahia, Brazil, who were exposed to different Mn levels owing to different Mn dust deposition rates. The Mn content was determined in the toenails (MnTn), hair (MnH), and blood (MnB), in addition to blood lead levels (PbB), by using graphite furnace atomic absorption spectrometry. Luteinizing hormone (LH), prolactin (PRL), estradiol (E2), testosterone (T), and thyroid stimulating hormone (TSH) levels were determined by using a chemiluminescence method. Of the total participants, 50.2% were boys, with an average age of 9 years. PRL values were higher in children attending the school with a higher Mn deposition rate (p < 0.004). We observed that MnTn was positively correlated with PRL levels and exhibited a non-linear association with LH levels. None of the tested Mn biomarkers were associated with E2, T, or TSH levels. To date, despite several animal studies that have focused on the correlation between Mn exposure and the endocrine regulation of hormones and pubertal development, very few studies have reported a similar relationship between environmental Mn effects and the human endocrine system. Our findings support the hypothesis that elevated exposure to Mn in children may be associated with hormonal imbalances that might trigger the early onset of puberty.

Relationship Among Mothers' Glycemic Level, Periodontitis, and Birth Weight.

BACKGROUND: The aim of this study is to determine the influence of glycemic level on the relationship between periodontitis and low birth weight (LBW). METHODS: A case-control study was conducted with 372 females divided into cases (109 mothers of newborns with birth weight < 2,500 g) and controls (263 mothers of newborns with birth weight ≥ 2,500 g). The birth weight of children was obtained from medical records, whereas information on sociodemographic, lifestyle, and health characteristics of the participants was obtained through an interview. Glycated hemoglobin (HbA1c) levels were measured, and probing depth, clinical attachment levels, and bleeding on probing were used to determine the periodontal status. Results were analyzed using logistic regression. RESULTS: The likelihood of having children with LBW among the mothers with periodontitis was six times greater than that observed among mothers without periodontitis (adjusted odds ratio [OR adjusted] = 6.02, 95% confidence interval [CI] = 2.47 to 15.17), even after adjustment. There was also a strong, statistically significant relationship between periodontitis and LBW in both the normal glycemic-level group (HbA1c levels < 5.6%, unadjusted odds ratio [OR unadjusted] = 8.30, 95% CI = 3.56 to 19.35) and the high glycemic-level group (HbA1c levels ≥ 5.6% and < 6.5%, OR unadjusted = 5.73, 95% CI = 1.75 to 18.70). After adjustment for confounders, the magnitude of the association continued to be strong in the normal glycemic-level group (OR adjusted = 7.59, 95% CI = 2.7 to 24.28), an increase of 25% when compared to the main association measurement. In those with high glycemic levels (OR adjusted = 4.03, 95% CI = 0.81 to 19.96), the OR decreased almost 50%, and the association lost statistical significance. CONCLUSION: Periodontitis and glycemic levels appeared to have opposing influences on birth weight, with periodontitis being associated with LBW and the magnitude of the association being altered depending on maternal blood glucose level.

Crescimento em meninos e meninas com puberdade precoce / Growth in boys and girls with precocious puberty

O desenvolvimento puberal acompanha-se de aceleraçäo da velocidade de crescimento, secundária à elevaçäo dos esteróides sexuais, do hormônio de crescimento e do IGF-1. O número de centímetros ganhos nesse período representa 16 por cento da estatura adulta. A puberdade precoce (PP) pode levar à fusäo prematura da cartilagem de crescimento, reduzindo a duraçäo do crescimento e a estatura final. Assim, o principal objetivo do tratamento frenador da PP é evitar o comprometimento estatural. É importante ressaltar que a PP näo evolui uniformemente, podendo ter curso lento (slow evolutive form) e näo requerer tratamento. Os autores abordam aspectos do crescimento puberal normal, da puberdade precoce e suas variantes, destacando os efeitos do tratamento com GnRHa (análogos de GnRH) na estatura adulta. Situaçöes especiais, como as puberdades avançada e acelerada, säo também discutidas