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1.
J Intern Med ; 2018 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-29806961

RESUMO

According to the World Health Organization (WHO), tuberculosis is the leading cause of death attributed to a single microbial pathogen worldwide. In addition to the large number of patients affected by tuberculosis, the emergence of Mycobacterium tuberculosis drug-resistance is complicating tuberculosis control in many high-burden countries. During the past 5 years, the global number of patients identified with multidrug-resistant tuberculosis (MDR-TB), defined as bacillary resistance at least against rifampicin and isoniazid, the two most active drugs in a treatment regimen, has increased by more than 20% annually. Today we experience a historical peak in the number of patients affected by MDR-TB. The management of MDR-TB is characterized by delayed diagnosis, uncertainty of the extent of bacillary drug-resistance, imprecise standardized drug regimens and dosages, very long duration of therapy and high frequency of adverse events which all translate into a poor prognosis for many of the affected patients. Major scientific and technological advances in recent years provide new perspectives through treatment regimens tailor-made to individual needs. Where available, such personalized treatment has major implications on the treatment outcomes of patients with MDR-TB. The challenge now is to bring these adances to those patients that need them most.

2.
Int J Tuberc Lung Dis ; 22(9): 972-982, 2018 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-30092861

RESUMO

The transmission of tuberculosis (TB) occurs mainly via inhalation of airborne droplet nuclei; however, the precise details of this process remain uncertain. We reviewed the literature from 1870 to 1940, when Mycobacterium tuberculosis was discovered and the concept of transmission emerged as a hallmark of the infectious disease. By 1940, laboratory experiments, animal studies and clinical observation had demonstrated that cough was central to TB transmission, and that guinea pigs close to patients with cough could be infected, mainly by patients coughing small droplets likely containing only 1-2 bacilli. A minority of pulmonary TB patients, usually during the early stages of the disease, with thin watery sputum, more successfully coughed small infectious droplets than patients with heavily smear-positive tenacious sputum who were often too ill and too weak to cough vigorously. There was ongoing debate regarding the possible importance of desiccated sputum particles found in surface dust. Investigation of TB transmission has a history of more than 130 years.


Assuntos
Tosse/microbiologia , Mycobacterium tuberculosis/isolamento & purificação , Pesquisa/tendências , Tuberculose Pulmonar/história , Tuberculose Pulmonar/transmissão , Aerossóis , Animais , Modelos Animais de Doenças , Poeira , Cobaias , História do Século XIX , História do Século XX , Humanos , Escarro/microbiologia
3.
Int J Tuberc Lung Dis ; 22(12): 1443-1449, 2018 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-30606316

RESUMO

SETTING: The household contacts (HHCs) of multidrug-resistant tuberculosis (MDR-TB) index cases are at high risk of tuberculous infection and disease progression, particularly if infected with the human immunodeficiency virus (HIV). HIV testing is important for risk assessment and clinical management. METHODS: This was a cross-sectional, multi-country study of adult MDR-TB index cases and HHCs. All adult and child HHCs were offered HIV testing if never tested or if HIV-negative >1 year previously when last tested. We measured HIV testing uptake and used logistic regression to evaluate predictors. RESULTS: A total of 1007 HHCs of 284 index cases were enrolled in eight countries. HIV status was known at enrolment for 226 (22%) HHCs; 39 (4%) were HIV-positive. HIV testing was offered to 769 (98%) of the 781 remaining HHCs; 544 (71%) agreed to testing. Of 535 who were actually tested, 26 (5%) were HIV-infected. HIV testing uptake varied by site (median 86%, range 0-100%; P < 0.0001), and was lower in children aged <18 years than in adults (59% vs. 78%; adjusted for site P < 0.0001). CONCLUSIONS: HIV testing of HHCs of MDR-TB index cases is feasible and high-yield, with 5% testing positive. Reasons for low test uptake among children and at specific sites-including sites with high HIV prevalence-require further study to ensure all persons at risk for HIV are aware of their status.


Assuntos
Infecções por HIV/diagnóstico , Programas de Rastreamento/estatística & dados numéricos , Aceitação pelo Paciente de Cuidados de Saúde/estatística & dados numéricos , Tuberculose Resistente a Múltiplos Medicamentos/complicações , Adolescente , Adulto , Criança , Estudos Transversais , Países em Desenvolvimento , Características da Família , Feminino , Infecções por HIV/complicações , Infecções por HIV/epidemiologia , Humanos , Internacionalidade , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Prevalência , Fatores de Risco , Índice de Gravidade de Doença , Tuberculose Resistente a Múltiplos Medicamentos/epidemiologia , Adulto Jovem
4.
Diagn Cytopathol ; 44(5): 363-8, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26853711

RESUMO

BACKGROUND: Liquid-based cytology (LBC) and rapid on-site evaluation (ROSE) are proposed to improve the quality of fine needle aspirates (FNA) and their diagnostic yield compared with conventional smear cytology (CSC). This prospective study directly compared outcomes of sonar-guided FNA of thoracic tumors supported by LBC, CSC, or CSC with ROSE. METHODS: Three aspirates each for both LBC and CSC with separate 22G spinal needles in a randomized, alternating sequence during 64 transthoracic FNA of thoracic tumors were collected. Smears were prepared by cytology staff on site but evaluated with ROSE only when all six samples had been collected. If no diagnostic material was found on the first three CSC additional needle passes guided by ROSE were performed. RESULTS: Final diagnoses were non-small cell lung cancer in 50 (78.1%), small cell lung cancer in 11 (17.2%), mesothelioma in 1 (1.6%), and inflammation in 2 cases (3.1%), respectively. LBC and CSC were diagnostic in 42 (65.6%) and 49 (76.6%) cases, respectively (P = 0.039), with both methods diagnostic in 41 cases (64.1%). Fifteen cases (23.4%) remained undiagnosed following three passes for CSC but 9 (14.1%) of these were diagnosed using FNA and ROSE with a total yield of 58 cases (90.6%; P < 0.001). CONCLUSION: The diagnostic yield of transthoracic FNA submitted for LBC is significantly lower than with CSC when slides are prepared professionally. ROSE significantly increases the yield of transthoracic FNA.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/patologia , Carcinoma de Células Pequenas/patologia , Neoplasias Pulmonares/patologia , Mesotelioma/patologia , Biópsia por Agulha Fina/métodos , Humanos , Distribuição Aleatória , Sensibilidade e Especificidade
5.
S Afr Med J ; 105(12): 1049-52, 2015 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-26792164

RESUMO

BACKGROUND: Integrated positron emission tomography/computed tomography (PET-CT) is a well-validated modality for assessing pulmonary mass lesions and specifically for estimating risk of malignancy. Tuberculosis (TB) is known to cause false-positive PET-CT findings. OBJECTIVE: To investigate the utility of PET-CT in the evaluation of pulmonary mass lesions and nodules in a high TB prevalence setting. METHODS: All patients referred for the evaluation of a solitary pulmonary nodule or mass and who underwent PET-CT scanning over a 3-year period were included. The PET-CT findings, including maximum standardised uptake value (SUVmax), were compared with the gold standard (tissue or microbiological diagnosis). The sensitivity, specificity, positive and negative predictive values and diagnostic accuracy for malignant disease were calculated according to the SUVmax cut-off of 2.5 and a proposed cut-off obtained from a receiver operating characteristic (ROC) curve. RESULTS: Forty-nine patients (mean (standard deviation) age 60.1 (10.2) years; 29 males) were included, of whom 30 had malignancy. Using an SUVmax cut-off of 2.5, PET-CT had a sensitivity, specificity, positive and negative predictive value and diagnostic accuracy for malignancy of 93.3%, 36.8%, 70.0%, 77.8% and 71.4%, respectively. After a ROC curve analysis, a suggested SUVmax cut-off of 5.0 improved the specificity to 78.9% and the diagnostic accuracy to 86.7%, with a small reduction in sensitivity to 90.0%. CONCLUSIONS: The diagnostic accuracy of PET-CT in the evaluation of pulmonary mass lesions using the conventional SUVmax cut-off of 2.5 was reduced in a TB-endemic area. An SUVmax cut-off of 5.0 has a higher specificity and diagnostic accuracy for malignancy, with a comparable sensitivity.

6.
J Invest Dermatol ; 78(3): 253-5, 1982 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-7199067

RESUMO

In the animal model of the Syrian hamster the antiandrogenic action of spironolactone on the sebaceous glands of the ventral side of the pinna was examined. Spironolactone reduces both labeling index and cross-sectional surface area of sebaceous glands significantly in a dose-dependent manner. Equally there was a significant decrease in serum testosterone levels in spironolactone treated animals. Our results seem to justify clinical studies with spironolactone in patients with hirsutism, seborrhea, and possibly acne vulgaris.


Assuntos
Glândulas Sebáceas/efeitos dos fármacos , Espironolactona/farmacologia , Animais , Divisão Celular/efeitos dos fármacos , Ritmo Circadiano , Cricetinae , Relação Dose-Resposta a Droga , Masculino , Mesocricetus , Glândulas Sebáceas/citologia , Espironolactona/administração & dosagem , Testosterona/antagonistas & inibidores , Testosterona/sangue
7.
J Invest Dermatol ; 83(3): 157-60, 1984 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-6540791

RESUMO

The photoperiod (i.e., the daylight fraction of the 24-h day and its seasonal changes) influences the annual cycle of many mammalian species. Especially the Syrian hamster (Mesocricetus auratus), which is an appropriate animal model to investigate the sebaceous gland activity, shows a strong photoperiodism controlling the sexual development as well as the function of androgen-controlled organs such as sebaceous glands. Short photoperiods with accompanying long dark periods lead to a sexual regression while long photoperiods stimulate the recrudescence. In light-physiologic studies Syrian hamsters were exposed to different light schedules. The daily light exposure was increased from 8 to 12, 13, 14, and 16 h. Sebaceous gland areas, weight of testes and accessory glands, tubular areas, and plasma levels of testosterone were determined. Syrian hamsters are sexually stimulated at a daily light exposure of 14 h. Below this light threshold the sexual regression begins. At a light schedule of 8 h the testes shrink, plasma testosterone levels and sebaceous gland areas show a significant reduction ("photoperiodic castration"). Therefore, in experiments of androgen-controlled organs of the Syrian hamster a minimum daily light period of 14 or 16 h is necessary for a sufficient testicular function and therefore for an effective stimulation of the sebaceous gland activity. Control animals of the same age and the same light schedule should be required to avoid pitfalls of photoperiodic effects.


Assuntos
Ritmo Circadiano , Glândulas Sebáceas/fisiologia , Espermatogênese , Testículo/fisiologia , Animais , Cricetinae , Masculino , Mesocricetus , Tamanho do Órgão , Glândulas Sebáceas/anatomia & histologia , Túbulos Seminíferos/anatomia & histologia , Testículo/anatomia & histologia , Testosterona/sangue
8.
J Clin Endocrinol Metab ; 57(2): 311-5, 1983 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-6863478

RESUMO

Testosterone and androstenedione were measured in testicular and epididymal tissue of 37 previously healthy infants between 1 and 24 months of age who died suddenly. In half of the patients elevated plasma levels of cortisol and androstenedione suggested preterminal stress. Plasma testosterone levels, however, did not differ from those in healthy infants. Testicular testosterone concentrations were maximal in boys from 1-3 months of age (median, 36.6 ng/g; range, 7-380 ng/g) with peak values similar to those found in pubertal or even adult testes. Thereafter testicular testosterone concentrations decreased and after the age of 6 months all values were below 12.5 ng/g, which corresponds to the low normal range of older prepubertal boys. Plasma testosterone and testicular testosterone correlated significantly (P less than 0.001). On average the testicular concentrations were 36.4 times higher than the corresponding plasma concentrations. Testicular androstenedione was low but correlated significantly with testicular testosterone (P less than 0.001). Epididymal testosterone concentrations were surprisingly high (1-3 months: median, 10.3 ng/g; range, 4-42.7 ng/g) and averaged 30% of the testicular testosterone concentration. Thus, epididymal testosterone concentrations were significantly higher than the circulating plasma testosterone levels, indicating the capacity of the infant epididymis to accumulate androgens. These findings suggest that high local testosterone concentrations during early infancy are important not only for the testis itself but particularly for the developing epididymis.


Assuntos
Envelhecimento , Androstenodiona/metabolismo , Epididimo/metabolismo , Testículo/metabolismo , Testosterona/metabolismo , Androstenodiona/sangue , Pré-Escolar , Humanos , Hidrocortisona/sangue , Lactente , Masculino , Testosterona/sangue
9.
J Clin Endocrinol Metab ; 62(2): 331-5, 1986 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-3941161

RESUMO

Androstenedione and testosterone were measured in whole adrenal glands of 56 previously healthy boys who died suddenly between birth and 2 yr of age. In each adrenal gland, the concentration of androstenedione considerably exceeded that of testosterone. The highest concentrations were found during the first week of life (median, 295 ng/g; range, 98-320 ng/g). Thereafter, values decreased rapidly until the end of the first year of life (median, 10 ng/g; range, 4.4-22.7 ng/g). Adrenal testosterone concentrations averaged 15% of those of androstenedione in the same gland and similarly decreased until the end of the first year. The decrease of adrenal androgen concentrations paralleled the involution of the fetal adrenal zone. A close correlation existed between the concentration of androstenedione in adrenal tissue and plasma. However, no correlation existed between adrenal and plasma testosterone. When the adrenals and testes of the same infant were compared, there was 10 times more androstenedione in the adrenals than in the testes during the first 2 yr of life. The testes contained more testosterone than the adrenals only during the first 4 months. Thus, in infant boys the adrenals are the main source of androstenedione during the first 2 yr. After the sixth month of life, they also are the main source of testosterone.


Assuntos
Glândulas Suprarrenais/metabolismo , Androstenodiona/biossíntese , Testosterona/biossíntese , Envelhecimento , Androstenodiona/sangue , Pré-Escolar , Humanos , Hidrocortisona/sangue , Lactente , Recém-Nascido , Masculino , Tamanho do Órgão , Testículo/metabolismo , Testosterona/sangue
10.
J Clin Endocrinol Metab ; 60(4): 757-63, 1985 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-2982907

RESUMO

Human leukocyte antigen (HLA) alleles and plasma 17-hydroxyprogesterone levels after ACTH stimulation were studied in 134 German families of patients with the salt-wasting (SW), simple virilizing (SV), or nonclassical (NC) late-onset form of congenital adrenal hyperplasia (CAH). Unexpected hormonal evidence for CAH was found in 6 otherwise healthy members of the relatives' group, who, therefore, were considered to be NC cryptic cases. HLA typing revealed a genetic difference between the 2 classical disease forms; SW CAH was strongly associated with Bw47, whereas SV CAH was closely linked to B5(w51). It also confirmed the nearly complete connection of NC CAH with B14. These alleles, especially Bw47 and B14, are mostly components of normally rare haplotypes: A3,Bw47,DR7 and Aw33,B14,DR1, respectively. They do not occur in the families' disease-unaffected haplotypes. Thus, it may be that all or almost all individuals from the general population bearing 1 of them are in fact CAH heterozygotes. Moreover, it seems possible to predict the severity of an infant's disease from his genomic type. The HLA linkage data were consistent with those obtained from ACTH testing, which showed significantly higher 17-hydroxyprogesterone increases in the genetically defined heterozygous relatives of SW patients than in the respective members of SV families. Of the families, 2 were also informative for mapping of the CAH disease gene(s) within the HLA-B to Glo interval.


Assuntos
Hiperplasia Suprarrenal Congênita/genética , Virilismo/genética , 17-alfa-Hidroxiprogesterona , Hiperplasia Suprarrenal Congênita/classificação , Hiperplasia Suprarrenal Congênita/complicações , Hormônio Adrenocorticotrópico , Cromossomos Humanos 6-12 e X , Feminino , Marcadores Genéticos , Genótipo , Haploidia , Heterozigoto , Humanos , Hidroxiprogesteronas/sangue , Masculino , Fenótipo , Virilismo/classificação , Virilismo/etiologia
11.
J Clin Endocrinol Metab ; 46(6): 971-85, 1978 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-263476

RESUMO

In order to obtain the still lacking reference data of individual plasma steroids in the immediate postnatal period needed for the assessment of adrenocortical function in various neonatal maladaptation syndromes, aldosterone (A), corticosterone, deoxycorticosterone (DOC), progesterone (P), 17-hydroxyprogesterone (17-OHP), cortisol, and cortisone were simultaneously followed in the same human newborn in a single 250-500 microliters peripheral plasma sample obtained at constant times during the first week of life using a mechanized Sephadex LH-20 multicolumn chromatography and standardized RIAs. Mean concentrations in 12 spontaneously delivered full term newborns of either sex and in paired umbilical (UV) and peripheral maternal (MV) venous plasma are given in the table. Besides significant maternoumbilical gradients in each steroid, DOC, P, 17-OHP, and cortisone, originating predominantly from the fetoplacental unit, disappear rapidly with steadily increasing half-lives. A, corticosterone, and cortisol, however, remain elevated in comparison with later infancy, with the exception of a marked "glucocorticoid dip" in cortisol and corticosterone levels between 2 and 12 h after birth.


Assuntos
Corticosteroides/sangue , Parto Obstétrico , Progesterona/sangue , 17-alfa-Hidroxiprogesterona , Adulto , Aldosterona/sangue , Corticosterona/sangue , Cortisona/sangue , Desoxicorticosterona/sangue , Feminino , Sangue Fetal/análise , Humanos , Hidrocortisona/sangue , Hidroxiprogesteronas/sangue , Recém-Nascido , Gravidez , Radioimunoensaio , Fatores de Tempo
12.
J Clin Endocrinol Metab ; 52(3): 385-92, 1981 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-7462398

RESUMO

Corticosteroids (CS) are essential for fetal organ maturation; yet, knowledge of endogeneous CS and precursor levels throughout fetal life is limited. Therefore, unconjugated aldosterone (Aldo), corticosterone (B), 11-deoxycorticosterone (DOC), progesterone (P), 17 alpha-hydroxyprogesterone (17-OHP), 11-deoxycortisol (S), cortisol (F), and cortisone (E) were simultaneously determined by RIA after automated Sephadex LH-20 chromatography in 70 control samples of amniotic fluid (AF) obtained at all gestational ages between 14-42 weeks. Levels of the progestins P and 17-OHP slowly increased from means (+/- SE) of 14.7 +/- 2.8 and 1.63 +/- 0.21 ng/ml, respectively, in early gestation to maximum levels of 32.4 +/- 3.5 and 3.80 +/- 0.74 ng/ml at 36-38 weeks (P less than 0.005), then dropped significantly (P less than 0.01) to 19.2 +/- 2.2 and 1.58 +/- 0.22 ng/ml at term. All CS levels except E rose very markedly by 3- to 12-fold (P less than 0.0001) from the weeks 14-16 (DOC, 0.44 +/- 0.08; B, 1.49 +/- 0.23; Aldo, 0.043 +/- 0.012; S, 0.51 +/- 0.10; F, 5.96 +/- 0.93 ng/ml) until the 36-38th weeks (DOC, 3.50 +/- 0.66; B, 4.60 +/- 0.78; Aldo, 0.530 +/- 0.109; S, 6.00 +/- 0.75; F, 60.8 +/- 8.9 ng/ml). Term levels were significantly reduced (P less than 0.01) in the less active CS DOC (0.51 +/- 0.07 ng/ml), B (2.35 +/- 0.35 ng/ml), and S (1.14 +/- 0.14 ng/ml), whereas those of the biologically most potent CS Aldo and F declined less markedly (0.272 +/- 0.053 and 23.0 +/- 0.75 ng/ml, respectively, at 39-42 weeks). Levels of the inactive glucocorticoid E rose from 8.83 +/- 1.08 ng/ml at 14-16 weeks to 16.8 +/- 2.6 ng/ml at 31-35 weeks (P less than 0.01), then remained rather constant around 11.5 ng/ml until term. It is concluded that after the 25th week, large amounts of biologically active CS are available in AF which probably directly induce the final epithelial maturation of fetal lungs and intestinal tract.


Assuntos
Corticosteroides/análise , Líquido Amniótico/análise , Gravidez , Aldosterona/análise , Corticosterona/análise , Cortisona/análise , Cortodoxona/análise , Desoxicorticosterona/análise , Feminino , Humanos , Hidrocortisona/análise , Hidroxiprogesteronas/análise , Progesterona/análise , Fatores de Tempo
13.
J Clin Endocrinol Metab ; 65(5): 862-7, 1987 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-3667883

RESUMO

To determine the origin of estrogens in infant blood, we measured estrone (E1) and estradiol (E2) in the gonads of 50 girls and 64 boys who died suddenly between birth and 2 yr of age as well as in the adrenals of 18 of these infant girls and 16 of the boys. In the adrenals, E1 [median, 2.8 ng/g (10.4 pmol/g); range, 1.1-4.8 ng/g (4.1-17.8 pmol/g)] and E2 [median, 3.0 ng/g (10.9 pmol/g); range, 1.2-5.3 ng/g (4.4-19.5 pmol/g)] were found in similar concentrations and were independent of age and sex. In the gonads, E2 was the major estrogen, but the concentrations differed markedly between the sexes; E2 exceeded E1 almost 10-fold in the ovaries and 2-fold in the testes. On the average, the gonads of the infant girls had 5 times more E2 and 2 times more E1 than those of the boys. As in plasma, E2 concentrations were highest in the ovaries of 1- to 6-month-old girls [median, 10.5 ng/g (38.5 pmol/g); range, 1.1-55.1 ng/g (4.0-202.0 pmol/g)] and in testes of 1- to 3-month-old boys [median, 1.8 ng/g (6.6 pmol/g); range, 0.6-6.4 ng/g (2.3-23.5 pmol/g)]. Ovarian E2 concentrations declined to less than 3.0 ng/g (11.0 pmol/g) by the end of the first year of life, and testicular E2 declined to less than 1.0 ng/g (3.7 pmol/g) after only 6 months of age. Gonadal estrogen concentrations paralleled changes in gonadal morphology. Ovarian weights varied in a pattern of rise and fall similar to that of ovarian E2 concentrations; the biggest ovaries contained multiple macroscopic cysts. Testicular E2 closely correlated with Leydig cell development and testicular testosterone concentrations. We infer, therefore, that the surge of plasma E2 in infant girls originates from ovarian follicles and that of boys from testicular Leydig cells, and that these both occur as a result of the postnatal surge in gonadotropin secretion. The basal plasma E1 and E2 pool, however, is derived from the adrenals and remains at a comparatively constant level in both sexes.


Assuntos
Glândulas Suprarrenais/metabolismo , Estradiol/metabolismo , Estrona/metabolismo , Ovário/metabolismo , Testículo/metabolismo , Glândulas Suprarrenais/crescimento & desenvolvimento , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Concentração Osmolar , Ovário/crescimento & desenvolvimento , Testículo/crescimento & desenvolvimento
14.
J Clin Endocrinol Metab ; 85(1): 134-8, 2000 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-10634376

RESUMO

During childhood, the quiescent phase of testicular activity, the hCG stimulation test is widely used to evaluate testicular function. Inhibin B, a gonadal peptide regulating FSH secretion, is an established marker of Sertoli cell function and spermatogenesis in adults. In contrast to the other hormones of the hypothalamo-pituitary-gonadal axis, inhibin B is also secreted in detectable amounts during childhood. The aim of this study was to determine whether basal inhibin B levels are able to predict prepubertal testicular function, so as to avoid a stimulation test. Inhibin B and testosterone before and after hCG stimulation were measured in 54 male children with various testicular disorders by an immunoassay specific for inhibin B. Basal inhibin B was compared to the testosterone increase after hCG. Inhibin B and the hCG-induced testosterone increment correlated strongly (r = 0.84; P<0.0001). Patients with anorchia were clearly distinguishable from those with abdominal testes, having undetectable (inhibin B, <15 pg/mL) respective normal inhibin B levels for age. Inhibin B and the testosterone response to hCG were low in boys with testicular damage (delayed diagnosis of cryptorchidism; after testicular torsion) and in patients with gonadal dysgenesis, but were normal or increased in children with androgen insensitivity syndrome. We conclude that basal inhibin B predicts the testosterone response to hCG in boys and therefore gives reliable information about both the presence and function of the testes. The diagnostic procedure in cryptorchidism may be reduced to a single inhibin B measurement. Furthermore, inhibin B levels show specific alterations in patients with sexual ambiguity, adding a valuable diagnostic tool to the complex differential diagnosis of male pseudohermaphroditism.


Assuntos
Gonadotropina Coriônica/farmacologia , Inibinas/sangue , Inibinas/metabolismo , Testosterona/sangue , Adolescente , Adulto , Envelhecimento/metabolismo , Criança , Pré-Escolar , Humanos , Lactente , Masculino , Valores de Referência , Estimulação Química , Doenças Testiculares/metabolismo , Testículo/crescimento & desenvolvimento
15.
J Clin Endocrinol Metab ; 65(1): 208-10, 1987 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-3584398

RESUMO

We reported previously reference values for seven corticosteroids in the plasma of term neonates and their mothers, including values for aldosterone (Aldo) that appeared high compared to the values in the literature. Plasma 11-deoxycortisol (S) was not measured in that longitudinal study. Using an improved technique of chromatographic separation of Aldo and S, the Aldo levels were measured again, and S levels were newly determined in stored plasma samples of the 12 newborn infants of our original report. The mean concentrations were: (Formula: see text). These plasma Aldo values should replace those of our original report. Thus, both plasma Aldo and S levels decline in the first week of life in normal infants.


Assuntos
17-Hidroxicorticosteroides/sangue , Aldosterona/sangue , Cortodoxona/sangue , Recém-Nascido/sangue , Cromatografia em Gel , Feminino , Humanos , Gravidez
16.
J Clin Endocrinol Metab ; 58(3): 574-7, 1984 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-6607266

RESUMO

The characteristic excess production of androgens in the cortisol 21-hydroxylase defect is generally considered to be secondary to ACTH stimulation of alternate pathways. Whenever a morphological examination of the adrenals has been possible in this disorder, adrenocortical hyperplasia was a constant finding. The availability of methods for the prenatal diagnosis of the 21-hydroxylase defect has made it possible to examine some of the manifestations of this disorder during fetal life. We studied a severely virilized 20-week-old aborted female fetus with the 21-hydroxylase defect whose adrenals were neither grossly enlarged nor microscopically hyperplastic. In a pregnancy at risk for congenital adrenal hyperplasia due to a 21-hydroxylase deficiency, amniocentesis was performed in the 18th week of gestation. The 21-hydroxylase defect was established by HLA typing and highly elevated levels of 17-hydroxyprogesterone, testosterone, and androstendione in amniotic fluid. After counselling, the parents, who already had a girl with the salt-wasting form of 21-hydroxylase deficiency, wished termination of the pregnancy. The aborted 20-week-old fetus was within the normal range for gestational age in weight and height. The external genitalia were ambiguous and extremely virilized, with an enlarged clitoris and fused labioscrotal folds. A urogenital sinus opened at the base of the clitoris. The internal organs were female, with a normal uterus and ovaries. Both adrenals were normal in size and weight for their gestational age. Histological examination of the adrenals revealed no abnormalities, and no hyperplasia was detectable. Thus, the adrenals in the 21-hydroxylase defect during fetal life secrete excessive amounts of androgens and cause virilization in the absence of adrenocortical hyperplasia.


Assuntos
Hiperplasia Suprarrenal Congênita/complicações , Doenças Fetais/enzimologia , Esteroide Hidroxilases/deficiência , Virilismo/enzimologia , Feminino , Doenças Fetais/genética , Doenças Fetais/patologia , Antígenos HLA/análise , Humanos , Cariotipagem , Gravidez , Virilismo/embriologia , Virilismo/patologia
17.
J Clin Endocrinol Metab ; 84(8): 2795-801, 1999 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10443682

RESUMO

Local aromatase-mediated conversion of androgens plays an important role in androgen action on the brain. To characterize estrogen formation in the human brain, we measured the microsomal aromatase activity of temporal lobe biopsies and compared it to that of human placenta using a highly sensitive 3H2O assay with [1beta-3H]androstenedione as substrate. Brain tissue was removed neurosurgically from 23 patients with epilepsy. Data of kinetic studies were analyzed with a computer-assisted, nonlinear, curve-fitting method using the Michaelis-Menten plus a nonspecific metabolism model. In contrast to data for placental aromatase activity, that for brain always had to be corrected for nonspecific tritium release. The mean K, values were 22.2 nmol/L in brain and 49.6 nmol/L in placenta. Inhibition experiments with atamestane, an inhibitor of aromatase cytochrome P450, revealed specific, dose-responsive, and competitive inhibition of both brain and placental aromatase activities. Placental aromatase activity was completely suppressible by atamestane, whereas in brain tissue there remained a residue of nonspecific tritium release. Subsequent experiments with cerebral cortex and subcortical white matter specimens of children and adults revealed a significantly higher aromatase activity in cerebral cortex than in subcortical white matter, but no sex or age differences were found.


Assuntos
Aromatase/metabolismo , Lobo Temporal/enzimologia , Adolescente , Adulto , Fatores Etários , Androstenodiona/análogos & derivados , Androstenodiona/metabolismo , Androstenodiona/farmacologia , Azasteroides/farmacologia , Criança , Relação Dose-Resposta a Droga , Feminino , Finasterida/farmacologia , Humanos , Cinética , Masculino , Pessoa de Meia-Idade , Especificidade de Órgãos , Placenta/enzimologia , Fatores Sexuais
18.
J Clin Endocrinol Metab ; 86(3): 1324-31, 2001 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11238528

RESUMO

Although androgen metabolism in the human brain was discovered almost 30 yr ago, conclusive studies on the enzymes involved are still lacking. We therefore investigated 5alpha-reductase and colocalized 3alpha-hydroxysteroid dehydrogenase (3alpha-HSD) activity in cerebral neocortex (CX) and subcortical white matter (SC) specimens neurosurgically removed from 44 patients suffering from epilepsy. We could demonstrate the presence of the 5alpha-reductase-3alpha-HSD complex in the biopsies of all patients under investigation. Inhibition experiments with specific inhibitors for 5alpha-reductase type 1 and type 2 revealed strong evidence for the exclusive activity of the type 1 isoform. We detected a significantly higher 5alpha-reductase activity in CX than in SC (P< 0.0001), but no sex-specific differences were observed. Furthermore, we found that, in contrast to liver, only 3alpha-HSD type 2 messenger RNA is expressed in the brain and that its expression is significantly higher in SC than in CX without sex-specific differences. The present study is the first to systematically characterize the 5alpha-reductase-3alpha-HSD complex in the human brain. The lack of sex-specific differences and also the colocalization of both enzymes at all life stages suggest a more general purpose of the complex, e.g. the synthesis of neuroactive steroids or the catabolism of neurotoxic steroids, rather than control of reproductive functions.


Assuntos
3-Hidroxiesteroide Desidrogenases/metabolismo , 3-Oxo-5-alfa-Esteroide 4-Desidrogenase/metabolismo , Encéfalo/enzimologia , Isoenzimas/metabolismo , 3-Hidroxiesteroide Desidrogenases/genética , 3-Oxo-5-alfa-Esteroide 4-Desidrogenase/genética , 3-alfa-Hidroxiesteroide Desidrogenase (B-Específica) , Inibidores de 5-alfa Redutase , Adolescente , Adulto , Idoso , Azasteroides/farmacologia , Criança , Pré-Escolar , Inibidores Enzimáticos/farmacologia , Epilepsia/enzimologia , Epilepsia/cirurgia , Feminino , Finasterida/farmacologia , Humanos , Concentração de Íons de Hidrogênio , Lactente , Isoenzimas/genética , Masculino , Microssomos/enzimologia , Pessoa de Meia-Idade , Neocórtex/enzimologia , RNA Mensageiro/análise , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Caracteres Sexuais , Lobo Temporal/enzimologia , Lobo Temporal/ultraestrutura , Distribuição Tecidual
19.
J Clin Endocrinol Metab ; 68(5): 863-8, 1989 May.
Artigo em Inglês | MEDLINE | ID: mdl-2715289

RESUMO

The maternal adrenal cortex seems to be involved in the adaptation to pregnancy. To study in detail adrenocortical secretion during pregnancy, we measured plasma aldosterone, corticosterone, 11-deoxycorticosterone, progesterone, 17-hydroxyprogesterone, 11-deoxycortisol, cortisol, and cortisone simultaneously by RIA after extraction and automated Sephadex LH-20 chromatography of 10 normal pregnant women longitudinally throughout pregnancy at weeks 8-10, 14-17, 21-24, 28-32, and 38 as well as at the time of admission to the delivery room. The mean plasma progesterone and 17-hydroxy-progesterone concentrations increased from 37.2 +/- 6.5 (+/- SE) and 8.2 +/- 1.0 nmol/L, respectively, in early gestation to maximum levels of 138.0 +/- 25.7 and 22.8 +/- 2.2 nmol/L at week 38 (P less than 0.01). Plasma glucocorticoid levels rose 2- to 3-fold (P less than 0.01) from weeks 8-10 (corticosterone, 18.5 +/- 5.4; 11-deoxycortisol, 1.9 +/- 0.2; cortisone, 24.2 +/- 4.2; cortisol, 195.5 +/- 37.6 nmol/L) to week 38 (corticosterone, 42.9 +/- 11.2; 11-deoxycortisol, 4.6 +/- 0.5; cortisone, 71.5 +/- 13.6; cortisol, 420 +/- 63 nmol/L). Similarly, plasma mineralocorticoid levels increased 5- to 7-fold (P less than 0.01) from weeks 8-10 (11-deoxycorticosterone, 0.69 +/- 0.12; aldosterone, 0.41 +/- 0.08 nmol/L) to maximum levels at week 38 (5.3 +/- 0.9 and 2.1 +/- 0.3 nmol/L, respectively). At the time of admission to the delivery room, plasma 11-deoxycortisol, corticosterone, and cortisol concentrations were higher (P less than 0.02) than at 38 weeks, but plasma progestin and mineralocorticoid concentrations were not. We conclude that the source of the elevated maternal corticosteroid levels in pregnancy in addition to the estrogen-mediated rise in corticosteroid-binding globulin is the maternal adrenal cortex itself. The peak glucocorticoid levels at admission to the delivery room reflect increased maternal and fetal stress with the onset of labor.


Assuntos
Córtex Suprarrenal/metabolismo , Glucocorticoides/sangue , Mineralocorticoides/sangue , Gravidez/sangue , Progestinas/sangue , 17-alfa-Hidroxiprogesterona , Córtex Suprarrenal/fisiologia , Adulto , Aldosterona/sangue , Corticosterona/sangue , Cortisona/sangue , Cortodoxona/sangue , Desoxicorticosterona/sangue , Feminino , Humanos , Hidrocortisona/sangue , Hidroxiprogesteronas/sangue , Estudos Longitudinais , Progesterona/sangue
20.
Neurology ; 55(6): 820-4, 2000 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-10994003

RESUMO

BACKGROUND: Epileptic discharges from the temporal lobe may influence the release of hormones from the hypothalamic-pituitary axis. If epilepsy surgery influences the underlying epileptic disorder one might expect serum hormone concentrations to return to normal following surgery. PATIENTS: Twenty-two men with epilepsy aged 25 to 48 years (mean, 34.9 years) were investigated before surgery and at 3, 6, and 12 months after surgery. Medication (all patients received carbamazepine) was maintained following surgery. METHODS: Hormone measurements included luteinizing hormone, follicle stimulating hormone, estradiol, testosterone, free testosterone, androstenedione, prolactin, dehydroepiandrosterone sulfate, cortisol, growth hormone, and sex hormone-binding globulin. These hormone levels were compared with those of 105 healthy men (mean age, 33.9 years). RESULTS: Fourteen of the 22 patients (63.6%) achieved total seizure control following epilepsy surgery. The 14 patients with successful seizure control entered further analysis. Before surgery these patients' free testosterone and androstenedione concentrations were significantly lower compared with healthy men. In seven of the 14 patients a significant increase of hormone serum concentrations could be demonstrated for testosterone, free testosterone, and androstenedione. Laterality of epileptic focus, enzyme-inducing medication, stress, and the decreasing number of patients during the follow-up did not correlate with the finding of a normalization of serum androgens. PATIENTS without complete seizure control did not show an increase in serum androgen concentrations. CONCLUSION: Successful temporal lobe epilepsy surgery may lead to a normalization of serum androgen concentrations in men with epilepsy.


Assuntos
Androgênios/sangue , Epilepsia do Lobo Temporal/sangue , Epilepsia do Lobo Temporal/cirurgia , Adulto , Humanos , Masculino , Pessoa de Meia-Idade , Valores de Referência , Fatores de Tempo
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