RESUMO
OBJECTIVES: To examine elevated neonatal inflammatory and neurotrophic proteins from children born extremely preterm in relation to later childhood brain Magnetic Resonance Imaging volumes and cognition. STUDY DESIGN: We measured circulating inflammation-related proteins and neurotrophic proteins on postnatal days 1, 7, and 14 in 166 children at 10 years of age (73 males; 93 females). Top quartile levels on ≥2 days for ≥3 inflammation-related proteins and for ≥4 neurotrophic proteins defined exposure. We examined associations among protein levels, brain Magnetic Resonance Imaging volumes, and cognition with multiple linear and logistic regressions. RESULTS: Analyses were adjusted for gestational age at birth and sex. Children with ≥3 elevated inflammation-related proteins had smaller grey matter, brain stem/cerebellar, and total brain volumes than those without elevated inflammation-related proteins, adjusted for neurotrophic proteins. When adjusted for inflammation-related proteins, children with ≥4 neurotrophic proteins, compared with children with no neurotrophic proteins, had larger grey matter and total brain volumes. Higher grey matter, white matter, and cerebellum and brainstem volumes were significantly correlated with higher IQ. Grey and white matter volumes were correlated with each other (r = -0.18; P = .021), and cerebellum and brainstem was highly correlated with grey matter (r = 0.55; P < .001) and white matter (r = 0.29; P < .001). Adjusting for other brain compartments, cerebellum and brainstem was associated with IQ (P = .016), but the association with white matter was marginally significant (P = .051). Grey matter was not associated with IQ. After adjusting for brain volumes, elevated inflammation-related proteins remained significantly associated with a lower IQ, and elevated neurotrophic proteins remained associated with a higher IQ. CONCLUSIONS: Newborn inflammatory and neurotrophin protein levels are associated with later brain volumes and cognition, but their effects on cognition are not entirely explained by altered brain volumes.
Assuntos
Encéfalo/anatomia & histologia , Encéfalo/diagnóstico por imagem , Cognição , Lactente Extremamente Prematuro/sangue , Imageamento por Ressonância Magnética , Biomarcadores/sangue , Proteínas Sanguíneas/análise , Criança , Feminino , Humanos , Recém-Nascido , Inflamação/sangue , Masculino , Fatores de Crescimento Neural/sangue , Tamanho do Órgão , Estudos ProspectivosRESUMO
CONTEXT: Steroid 5α-reductase inhibitors are used to treat benign prostatic hyperplasia and androgenic alopecia, but the role of 5α-dihydrotestosterone (DHT) in mediating testosterone's effects on muscle, sexual function, erythropoiesis, and other androgen-dependent processes remains poorly understood. OBJECTIVE: To determine whether testosterone's effects on muscle mass, strength, sexual function, hematocrit level, prostate volume, sebum production, and lipid levels are attenuated when its conversion to DHT is blocked by dutasteride (an inhibitor of 5α-reductase type 1 and 2). DESIGN, SETTING, AND PATIENTS: The 5α-Reductase Trial was a randomized controlled trial of healthy men aged 18 to 50 years comparing placebo plus testosterone enthanate with dutasteride plus testosterone enanthate from May 2005 through June 2010. INTERVENTIONS: Eight treatment groups received 50, 125, 300, or 600 mg/wk of testosterone enanthate for 20 weeks plus placebo (4 groups) or 2.5 mg/d of dutasteride (4 groups). MAIN OUTCOME MEASURES: The primary outcome was change in fat-free mass; secondary outcomes: changes in fat mass, muscle strength, sexual function, prostate volume, sebum production, and hematocrit and lipid levels. RESULTS: A total of 139 men were randomized; 102 completed the 20-week intervention. Men assigned to dutasteride were similar at baseline to those assigned to placebo. The mean fat-free mass gained by the dutasteride groups was 0.6 kg (95% CI, -0.1 to 1.2 kg) when receiving 50 mg/wk of testosterone enanthate, 2.6 kg (95% CI, 0.9 to 4.3 kg) for 125 mg/wk, 5.8 kg (95% CI, 4.8 to 6.9 kg) for 300 mg/wk, and 7.1 kg (95% CI, 6.0 to 8.2 kg) for 600 mg/wk. The mean fat-free mass gained by the placebo groups was 0.8 kg (95% CI, -0.1 to 1.7 kg) when receiving 50 mg/wk of testosterone enanthate, 3.5 kg (95% CI, 2.1 to 4.8 kg) for 125 mg/wk, 5.7 kg (95% CI, 4.8 to 6.5 kg) for 300 mg/wk, and 8.1 kg (95% CI, 6.7 to 9.5 kg) for 600 mg/wk. The dose-adjusted differences between the dutasteride and placebo groups for fat-free mass were not significant (P = .18). Changes in fat mass, muscle strength, sexual function, prostate volume, sebum production, and hematocrit and lipid levels did not differ between groups. CONCLUSION: Changes in fat-free mass in response to graded testosterone doses did not differ in men in whom DHT was suppressed by dutasteride from those treated with placebo, indicating that conversion of testosterone to DHT is not essential for mediating its anabolic effects on muscle. TRIAL REGISTRATION: clinicaltrials.gov Identifier: NCT00493987.
Assuntos
Inibidores de 5-alfa Redutase/farmacologia , Adiposidade/efeitos dos fármacos , Azasteroides/farmacologia , Força Muscular/efeitos dos fármacos , Reprodução/efeitos dos fármacos , Testosterona/análogos & derivados , Testosterona/metabolismo , 3-Oxo-5-alfa-Esteroide 4-Desidrogenase/metabolismo , Adulto , Índice de Massa Corporal , Método Duplo-Cego , Dutasterida , Hematócrito , Humanos , Lipídeos/sangue , Masculino , Pessoa de Meia-Idade , Próstata/anatomia & histologia , Próstata/efeitos dos fármacos , Sebo/efeitos dos fármacos , Sebo/metabolismo , Testosterona/administração & dosagem , Testosterona/fisiologia , Resultado do TratamentoRESUMO
AIM: Early breast cancer detection is important for intervention and prognosis. Advances in treatment and outcome require diagnostic tools with highly positive predictive value. PURPOSE: To study the potential role of quantitative MRI (qMRI) using T1/T2 ratios to differentiate benign from malignant breast lesions. METHODS: A cross-sectional study of 69 women with 69 known or suspicious breast lesions were scanned with mixed-turbo spin echo pulse sequence. Patients were grouped according to histopathological assessment of disease stage: untreated malignant tumor, treated malignancy and benign disease. RESULTS & DISCUSSION: Elevated T1/T2 means were observed for biopsy-proven malignant lesions and for malignant lesions treated prior to qMRI with chemotherapy and/or radiation, as compared with benign lesions. The qMRI-obtained T1/T2 ratios correlated with histopathology. Analysis revealed correlation between elevated T1/T2 ratio and disease stage. This could provide valuable complementary information on tissue properties as an additional diagnostic tool.
RESUMO
OBJECTIVE: To determine dose-dependent effects of T administration on cardiovascular risk markers in women with low T levels. METHODS: Seventy-one hysterectomized women with or without oophorectomy with total T < 31 ng/dL and/or free T < 3.5 pg/mL received a standardized transdermal estradiol regimen during the 12-week run-in period and were then randomized to receive weekly im injections of placebo or 3-, 6.25-, 12.5-, or 25-mg T enanthate for 24 weeks. Total and free T levels were measured by liquid chromatography-tandem mass spectrometry and equilibrium dialysis, respectively. Insulin resistance and inflammatory markers were measured at baseline and 24 weeks. In a subset of women, magnetic resonance imaging of the abdomen was performed to quantify abdominal fat volume. RESULTS: Fifty-nine women who completed the 24-week intervention were included in the final analysis. The five groups were similar at baseline. Mean on-treatment nadir total T concentrations were 14, 79, 105, 130, and 232 ng/dL in the placebo group and the 3-, 6.25-, 12.5-, and 25-mg groups, respectively. No significant changes in fasting glucose, fasting insulin, homeostatic model assessment of insulin resistance, high sensitivity C-reactive protein, adiponectin, blood pressure, and heart rate were observed at any T dose when compared to placebo. Similarly, no dose- or concentration-dependent changes were observed in abdominal fat on magnetic resonance imaging. CONCLUSION: Short-term T administration over a wide range of doses for 24 weeks in women with low T levels was not associated with worsening of cardiovascular risk markers.
Assuntos
Androgênios/deficiência , Doenças Cardiovasculares/sangue , Doenças Cardiovasculares/induzido quimicamente , Testosterona/administração & dosagem , Adulto , Biomarcadores/sangue , Relação Dose-Resposta a Droga , Feminino , Frequência Cardíaca/efeitos dos fármacos , Terapia de Reposição Hormonal/efeitos adversos , Humanos , Inflamação/sangue , Resistência à Insulina , Pessoa de Meia-Idade , Placebos , Fatores de Risco , Testosterona/efeitos adversos , Adulto JovemRESUMO
BACKGROUND: Androgen receptor (AR) knockout male mice display hepatic steatosis, suggesting that AR signaling may regulate hepatic fat. However, the effects of testosterone replacement on hepatic fat in men are unknown. The aim of this study was to determine the effects of testosterone administration on hepatic fat in older men with mobility limitation and low testosterone levels who were participating in a randomized trial (the Testosterone in Older Men trial). METHODS: Two hundred and nine men with mobility limitation and low total or free testosterone were randomized in the parent trial to either placebo or 10-g testosterone gel daily for 6 months. Hepatic fat was determined by magnetic resonance imaging in 73 men (36 in placebo and 37 in testosterone group) using the volumetric method. Insulin sensitivity (homeostatic model assessment-insulin resistance) was derived from fasting glucose and insulin. RESULTS: Baseline characteristics were similar between the two groups, including liver volumes (1583 ± 363 in the testosterone group vs 1522 ± 271 mL in the placebo group, p = .42). Testosterone concentrations increased from 250 ± 72 to 632 ± 363 ng/dL in testosterone group but did not change in placebo group. Changes in liver volume during intervention did not differ significantly between groups (p = .5) and were not related to on-treatment testosterone concentrations. The change in homeostatic model assessment-insulin resistance also did not differ significantly between groups and was not related to either baseline or change in liver fat. CONCLUSION: Testosterone administration in older men with mobility limitation and low testosterone levels was not associated with a reduction in hepatic fat. Larger trials are needed to determine whether testosterone replacement improves liver fat in men with nonalcoholic hepatic steatosis.