BACKGROUND The onset of puberty is first detected as an increase in pulsatile secretion of gonadotropin-releasing hormone (GnRH). Early activation of the hypothalamic–pituitary–gonadal axis results in central precocious puberty. The timing of pubertal development is driven in part by genetic factors, but only a few, rare molecular defects associated with central precocious puberty have been identified. METHODS We performed whole-exome sequencing in 40 members of 15 families with central precocious puberty. Candidate variants were confirmed with Sanger sequencing. We also performed quantitative real-time polymerase-chain-reaction assays to determine levels of messenger RNA (mRNA) in the hypothalami of mice at different ages. RESULTS We identified four novel heterozygous mutations in MKRN3, the gene encoding makorin RING-finger protein 3, in 5 of the 15 families; both sexes were affected. The mutations included three frameshift mutations, predicted to encode truncated proteins, and one missense mutation, predicted to disrupt protein function. MKRN3 is a paternally expressed, imprinted gene located in the Prader–Willi syndrome critical region (chromosome 15q11–q13). All affected persons inherited the mutations from their fathers, a finding that indicates perfect segregation with the mode of inheritance expected for an imprinted gene. Levels of Mkrn3 mRNA were high in the arcuate nucleus of prepubertal mice, decreased immediately before puberty, and remained low after puberty. CONCLUSIONS Deficiency of MKRN3 causes central precocious puberty in humans. (Funded by the National Institutes of Health and others.)
Clinical and laboratory diagnosis and treatment of central precocious puberty (CPP) remain challenging due to lack of standardization. The aim of this revision was to address the diagnostic and therapeutic features of CPP in Brazil based on relevant international literature and availability of the existing therapies in the country. The diagnosis of CPP is based mainly on clinical and biochemical parameters, and a period of follow-up is desirable to define the "progressive" form of sexual precocity. This occurs due to the broad spectrum of pubertal development, including isolated premature thelarche, constitutional growth and puberty acceleration, progressive and nonprogressive CPP, and early puberty. Measurement of basal and stimulated LH levels remains challenging, considering that the levels are not always in the pubertal range at baseline, short-acting GnRH is not readily available in Brazil, and the cutoff values differ according to the laboratory assay. When CPP is suspected but basal LH values are at prepubertal range, a stimulation test with short-acting or long-acting monthly GnRH is a diagnostic option. In Brazil, the treatment of choice for progressive CPP and early puberty is a long-acting GnRH analog (GnRHa) administered once a month or every 3 months. In Brazil, formulations of GnRHa (leuprorelin and triptorelin) are available and commonly administered, including 1-month depot leuprorelin 3.75 mg and 7.5 mg, 1-month depot triptorelin 3.75 mg, and 3-month depot leuprorelin 11.25 mg. Monthly or 3-month depot GnRHa are effective and safe to treat CPP. Arch Endocrinol Metab. 2016;60(2):163-72
BackgroundAtaxia telangiectasia (A-T) is a neurodegenerative disease that leads to mitochondrial dysfunction and oxidative stress. Insulin resistance (IR), type 2 diabetes and the risk for development of cardiovascular disease was recently associated as an extended phenotype of the disease. We aimed to assess IR; liver involvement; carotid intima-media thickness (cIMT) and metabolic alterations associated to cardiovascular risk in A-T patients, and relate them with age.ResultsGlucose metabolism alterations were found in 54.6% of the patients. Hepatic steatosis was diagnosed in 11/17 (64.7%) A-T patients. AST/ALT ratio > 1 was observed in 10/17 (58.8%). A strong positive correlation was observed between insulin sum concentrations with ALT (r = 0.782, p < 0.004) and age (r = 0.818, p = 0.002). Dyslipidemia was observed in 55.5% of the patients. The apolipoprotein (Apo-B)/ApoA-I ratio (r = 0.619; p < 0.01), LDL/HDL-c (r = 0.490; p < 0.05) and the Apo-B levels (r = 0.545; p < 0.05) were positively correlated to cIMT.ConclusionsMetabolic disorders implicated in cardiovascular and liver diseases are frequently observed in adolescent A-T patients and those tend to get worse as they become older. Therefore, nutritional intervention and the use of drugs may be necessary.
Purpose: The purpose of this study was to verify the correlation between neck circumference (NC) and body mass index (BMI) in children, and to determine NC percentiles for Brazilian children. Methods: The subjects of this cross-sectional study were students between the ages of 6 and 19 years from five schools in São Paulo, Brazil. Clinical and anthropometric data were collected from the students from April 2011 to June 2012. NC was measured at the level of the cricoid cartilage. We calculated Pearson correlation coefficients between NC and other indices of obesity with Sigma Stat 3.5. NC percentiles were produced using the LMS (lambda, mu, and sigma) method (STATA 12.0). Results: Among 2,794 students, 49.9% were male. NC was significantly correlated with age, BMI, waist circumference (WC), and body fat percentage (%BF). The NC of boys was greater than that of girls. The NC curves of smoothed 3rd, 10th, 25th, 50th, 75th, 90th, and 97th percentiles were constructed by age and sex. Conclusions: NC can be used in the assessment of obesity in childhood. There was a positive correlation between NC and BMI, WC and %BF. This study was the first to provide NC percentiles for children in Brazil.
WC showed direct correlation with anthropometric indexes commonly used and in preschool children wasn't predictor of cardiovascular risk.
Background and Aims: Evaluate the nutritional status, plasma concentration of vitamin E and markers of cardiovascular risk in ataxia telangiectasia (AT) patients. Methods: Cross-sectional study with 13 patients with AT and 22 healthy controls, evaluating the following factors: nutritional status, food intake, lipid profile, plasma concentration of vitamin E, malondialdehyde and high sensitivity C-reactive protein, linking them with atherosclerosis risk in AT patients. Results: Average age was 14.6 in the AT group, 30.8% were malnourished and 23.1% had stunting. A greater impairment of lean body mass was found in these patients. Concentrations of triglycerides (TG), total cholesterol (CT), LDL-c, non-HDL cholesterol (NHDL-c) were significantly higher in patients and HDL-c, lower. Vitamin E/total lipids and vitamin E/TG ratios were lower in the AT group, and significant inverse correlation between these ratios and NHDL-c, CT/HDL-c, and LDL-c/HDL-c, log TG/HDL-c was observed in the AT group. Alanine aminotransferase correlated directly and significantly with NHDL-c, CT/HDL-c and LDL-c/HDL-c, in patients. Conclusion: The alterations of lipid metabolism biomarkers suggestive of atherosclerotic risk of male AT patients coupled with lower vitamin E/total lipids ratio and low lean body mass may complicate the clinical course of the disease and emphasizes the importance of multidisciplinary care, routine monitoring of cardiovascular biomarkers and appropriate nutritional guidance.
Aromatase inhibitors (AIs) have been used to recover height loss due to their capacity to delay growth plate closure. Long-term studies describing final heights are needed to determine the efficacy and safety profiles of these drugs for the treatment of impaired growth. This study aims to identify the therapeutic efficiency of AIs in improve growth and to describe potential adverse effects during treatment. Retrospective data analysis of 96 adolescents, among which 22 patients already attained near-final height, were followed at outpatient clinics of two referral centers. Patients were all in puberty and present idiopathic decrease in predicted adult height. Patients were treated with Anastrozole (ANZ: 1 mg/day) or Letrozole (LTZ: 2.5 mg/day) with/without recombinant human growth hormone (0.05 mg/kg/day) for 1.0 to 3.5 years (2.1±1.2 years). Height gain, body mass index, lipid, liver enzyme, gonadotropins and testosterone levels were described before and at the end of treatment. Predicted adult height (PAH) and NF height were compared with the TH. The height SDS (adjusted to bone age) significantly increased (p<0.05) in all groups [0.8±0.7 (ANZ), 0.7±0.7 (ANZ+GH), 0.3±0.5 (LTZ), and 1.2±0.8 (LTZ+GH)]; the latter group exhibited the highest increment of PAH and growth recovery to the TH (p<0.004). No significant side effects were observed. AI treatment, especially when used in association with GH was able to improve growth and the attainment of familial target height.
Relative antiinflammatory and immunosuppressive potencies of glucocorticoids (GC) were previously well defined. Nonetheless, GC also regulate cell proliferation and programmed death (apoptosis). The aim of this study was to determine the relative potency of different GC on the modulation of cell survival. The GC-sensitive lymphoblast cell line CEM-c7/14 was submitted to 48 h-exposure to GC (dose-response curve from 10(-8) to 10(-5) M). Cell survival was analyzed employing the DimethylTiazol-Tetrazolium (MTT) test. For each GC at least 4 experiments were performed in quadruplicate. Responses to different GC at the same molarity were analyzed by ANOVA on Ranks. Cell responses to the same GC in different concentrations were tested by repeated measures ANOVA. The EC50 for each GC was calculated with the GraphPad Prism 3.0 software. The use of low concentrations (10(-8) and 10(-7) M) of hydrocortisone and methylprednisolone determined a similar effects on cell survival, which was less prominent than that observed with betamethasone, budesonide or momethasone. Momethasone was the most potent GC, inducing the most intense dexamethasone reduction on cell survival at the lowest concentration (10(-8) M). Momethasone and methylprednisolone were the two GC with the strongest impact on cell survival. Our findings suggest that antiproliferative and apoptotic potencies of GC are different from those previously reported antiinflammatory and immunosuppressive actions.
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