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1.
J Clin Endocrinol Metab ; 91(8): 3017-23, 2006 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16735493

RESUMO

CONTEXT: Subjects with complete androgen insensitivity (CAI) and 5alpha-reductase-2 deficiency (5alphaRD-2) are natural human models to study the direct effect of androgens on bone mineral density (BMD). OBJECTIVE: The objective of this study was to test the hypothesis that androgens have a direct effect on BMD in men. DESIGN: This was a prospective, observational study (1989-1999) using dual energy x-ray absorptiometry. SETTING: The study was set in an outpatient specialty referral center. PATIENTS OR OTHER PARTICIPANTS: All known subjects with these conditions (12 CAI and 16 5alphaRD-2) from diverse sociodemographic backgrounds were recruited for the study. INTERVENTIONS: There were no interventions. MAIN OUTCOME MEASURE: Mean Z score and weight-matched Z score at lumbar spine and femoral neck for CAI and 5alphaRD-2 subjects were determined. RESULTS: Twelve CAI subjects had mean Z score at L2-L4 of -2.84 (+/-0.97, P < 0.001) and a mean weight-matched Z score of -2.52 (+/-0.94, P < 0.001). The mean Z score at the femoral neck was -1.33 (+/-0.91, P < 0.001) and the mean weight-matched Z score was -1.10 (+/-0.82, P = 0.001). Sixteen 5alphaRD-2 subjects had a mean Z score at L2-L4 of -0.84 (+/-1.29, P = 0.02) and a mean weight-matched Z score for 15 of 16 patients of -0.44 (+/-1.08, P = 0.14). The mean Z score at the femoral neck was 0.14 (+/-1.02, P = 0.58) and the mean weight-matched Z score for 15 of 16 patients was 0.49 (+/-0.94, P = 0.06). Therefore, in CAI subjects, BMD was significantly decreased in the spine and hip. 5alphaRD-2 subjects had normal BMD values. CONCLUSIONS: 1) Androgens are of direct importance in the development and/or maintenance of BMD; and 2) testosterone and/or low levels of dihydrotestosterone appear to be sufficient for BMD development and/or maintenance.


Assuntos
Síndrome de Resistência a Andrógenos/fisiopatologia , Densidade Óssea/fisiologia , Colestenona 5 alfa-Redutase/deficiência , Absorciometria de Fóton , Adolescente , Adulto , Androgênios/fisiologia , Castração , Di-Hidrotestosterona , Colo do Fêmur , Humanos , Vértebras Lombares , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Testosterona/fisiologia
2.
J Clin Endocrinol Metab ; 89(10): 4850-6, 2004 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-15472175

RESUMO

PROP-1 gene mutations result in impaired production of GH, gonadotropins, TSH, and prolactin. We describe three adult siblings, aged 18-25 yr, with short stature, hypothyroidism, and lack of pubertal maturation, who were homozygous for 301-302delAG PROP-1 mutation. We had the unique opportunity to treat them in adulthood with GH for 4-5 yr and thyroid replacement before sex steroid replacement. Sibling 1, a female, had a chronological age (CA) of 25 yr 8 months, a bone age (BA) of 12.5 yr, and height of 128.7 cm [-5.29 sd score (SDS)]; sibling 2, a younger sister had a CA of 22 yr 5 months, a BA of 13 yr, and height of 137.5 cm (-3.94 SDS); and sibling 3, a male, had a CA of 18 yr 4 months, a BA of 11.5 yr, and height of 127.5 cm (-6.38 SDS). Despite delay in treatment and fairly advanced BA, all responded to GH and thyroid hormone therapy with a dramatic increase in linear growth: 22.3 cm for sibling 1, 22 cm for sibling 2, and 34.5 cm for sibling 3. After sex hormone replacement, siblings 1, 2, and 3 grew another 2.6, 3, and 9.5 cm to final heights of 153.6, 162.5, and 171.5 cm, respectively. In conclusion, the substantial linear growth in adult siblings with a PROP-1 mutation illustrates that despite an advanced BA, linear growth potential remains in adulthood in the setting of sex steroid deficiency.


Assuntos
Nanismo Hipofisário/tratamento farmacológico , Nanismo Hipofisário/genética , Proteínas de Homeodomínio/genética , Hormônio do Crescimento Humano/uso terapêutico , Adolescente , Adulto , Fatores Etários , Estatura/efeitos dos fármacos , Saúde da Família , Feminino , Humanos , Masculino , Linhagem , Irmãos
3.
J Androl ; 24(5): 681-7, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-12954658

RESUMO

Prostate cancer is a leading cause of cancer death in American males. Androgens play an essential role in prostate development, growth and pathogenesis of benign prostate hyperplasia, and prostate cancer. Although testosterone is the main androgen secreted from the testes, dihydrotestosterone (DHT), a more potent androgen converted from testosterone by 5alpha-reductase isozymes, type 1 and 2, is the major androgen in the prostate cells. Thus, 5alpha-reductase(s) are critical in determining androgen activity in the prostate. However, it is unclear in prostate tumor cells whether 1 or 2 5alpha-reductase isozymes are expressed and whether they are functionally important. In the present report, we studied the importance of 5alpha-reductase isozymes in the androgen induction of prostate-specific antigen (PSA) gene expression in LNCaP prostatic tumor cells. Treatment with either testosterone or DHT in LNCaP cells produced dose- and time-dependent increases in PSA levels in the cell media and in PSA messenger RNA (mRNA) levels in the cells. However, testosterone-induced but not DHT-induced PSA gene expression was significantly inhibited by finasteride, a 5alpha-reductase inhibitor, in a dose-dependent manner. Furthermore, we demonstrated for the first time that both 5alpha-reductase-1 and 5alpha-reductase-2 mRNAs were expressed in LNCaP cells using reverse transcriptase-polymerase chain reaction (RT-PCR) and RT-PCR Southern blot analysis. These results suggest that both 5alpha-reductase isozymes are present and functionally important in prostatic tumor LNCaP cells and that DHT is a major mediator of androgen induction of PSA gene expression in these cells.


Assuntos
Di-Hidrotestosterona/metabolismo , Regulação Neoplásica da Expressão Gênica/fisiologia , Antígeno Prostático Específico/genética , Neoplasias da Próstata , 3-Oxo-5-alfa-Esteroide 4-Desidrogenase/genética , 3-Oxo-5-alfa-Esteroide 4-Desidrogenase/metabolismo , Inibidores de 5-alfa Redutase , Androgênios/metabolismo , Androgênios/farmacologia , Linhagem Celular Tumoral , Di-Hidrotestosterona/farmacologia , Inibidores Enzimáticos/farmacologia , Finasterida/farmacologia , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Isoenzimas/antagonistas & inibidores , Isoenzimas/genética , Isoenzimas/metabolismo , Masculino , RNA Mensageiro/metabolismo , Testosterona/metabolismo , Testosterona/farmacologia
4.
Hum Brain Mapp ; 28(11): 1206-12, 2007 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17315226

RESUMO

Ventral anterior cingulate cortex (vACC) is a highly interconnected brain region considered to reflect the sometimes competing demands of cognition and emotion. A reciprocal relationship between vACC and dorsal ACC (dACC) may play a role in maintaining this balance between cognitive and emotional processing. Using functional MRI in association with a cognitively-demanding visuospatial task (mental rotation), we found that only women demonstrated vACC suppression and inverse functional connectivity with dACC. Sex differences in vACC functioning--previously described under conditions of negative emotion--are extended here to cognition. Consideration of participant sex is essential to understanding the role of vACC in cognitive and emotional processing.


Assuntos
Cognição/fisiologia , Emoções/fisiologia , Giro do Cíngulo/fisiologia , Córtex Pré-Frontal/fisiologia , Caracteres Sexuais , Adulto , Mapeamento Encefálico , Feminino , Lateralidade Funcional/fisiologia , Giro do Cíngulo/anatomia & histologia , Humanos , Imaginação/fisiologia , Imageamento por Ressonância Magnética , Masculino , Rede Nervosa/anatomia & histologia , Rede Nervosa/fisiologia , Inibição Neural/fisiologia , Testes Neuropsicológicos , Córtex Pré-Frontal/anatomia & histologia , Desempenho Psicomotor/fisiologia , Percepção Espacial/fisiologia
5.
Am J Med Genet A ; 122A(3): 193-200, 2003 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-12966519

RESUMO

11beta-hydroxylase deficiency, an autosomal recessive disorder, is the second most common cause of congenital adrenal hyperplasia. We studied four subjects with classic 11beta-hydroxylase deficiency and severe hypertension: a 46,XX affected subject from a Turkish family with severe ambiguity of the external genitalia and hypertension, and three affected 46,XY subjects from a Dominican kindred with isosexual precocious puberty and severe hypertension. The affected subjects had significantly elevated plasma 11-desoxycortisol, 11-desoxycorticosterone, Delta4-androstenedione, and testosterone. To determine the molecular genetic defects, genomic DNA was isolated from the leukocytes of affected subjects and their family members. The encoding region of the 11beta-hydroxylase gene (CYP11B1) was amplified by PCR with specific primers. Using single-stranded DNA conformational polymorphism (SSCP) and DNA sequencing, a nonsense mutation in exon 6 of CYP11B1 in the affected 46,XX subject from the Turkish family was identified, where a cytosine was substituted by a thymidine, resulting in the replacement of glutamine (CAG) by a stop codon (TAG) at amino acid position 338 (Q338X). In the three 46,XY Dominican boys, the mutation was also a nonsense mutation in exon 6 of CYP11B1, where a cytosine was substituted by a thymidine, resulting in the replacement of glutamine (CAG) by a stop codon (TAG) at amino acid position 356 (Q356X). Both mutations result in the biosynthesis of a truncated 11beta-hydroxylase protein with loss of enzymatic activity. Heterozygosity was determined in family members of both probands including parents and siblings. These results indicate that mutations of CYP11B1 in these subjects are responsible for their clinical syndromes.


Assuntos
Mutação , Esteroide 11-beta-Hidroxilase/genética , Hiperplasia Suprarrenal Congênita/enzimologia , Hiperplasia Suprarrenal Congênita/genética , Pré-Escolar , Códon sem Sentido , DNA/química , DNA/genética , Análise Mutacional de DNA , Saúde da Família , Feminino , Genótipo , Humanos , Masculino , Linhagem , Fenótipo , Polimorfismo Conformacional de Fita Simples , Esteroide 11-beta-Hidroxilase/metabolismo
6.
Rev. méd. domin ; 54(3): 55-7, oct.-dic. 1993. ilus
Artigo em Espanhol | LILACS | ID: lil-132115

RESUMO

Se realizó un estudio retrospectivo y longitudinal para determinar la frecuencia de tuberculosis pulmonar en el hospital Nuestra Señora de Regla de Baní, República Dominicana, durante el período 1988-1992, de un total de 284 casos estudiados el 17.6 por ciento osciló entre las edades de 19 y 28 años. El 58 por ciento de ellos fueron masculinos. Al 54.9 por ciento se le realizó baciloscopía como medio diagnóstico, y radiografía a un 33.3 por ciento . Un 37.7 por ciento abandonó el tratamiento. Al esquema de 7 meses correspondió un 88.7 por ciento y que fue eficaz para un 57.8 por ciento ; el 2.4 por ciento falleció


Assuntos
Humanos , Masculino , Feminino , Adulto , Tuberculose Pulmonar/epidemiologia , Estudos Retrospectivos
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