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1.
Ann Oncol ; 28(9): 2256-2263, 2017 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-28633409

RESUMEN

BACKGROUND: Immune checkpoint inhibitors improve outcomes compared with chemotherapy in lung cancer. Tumor PD-L1 receptor expression is being studied as a predictive biomarker. The objective of this study was to assess the cost-effectiveness and economic impact of second-line treatment with nivolumab, pembrolizumab, and atezolizumab with and without the use of PD-L1 testing for patient selection. DESIGN: We developed a decision-analytic model to determine the cost-effectiveness of PD-L1 assessment and second-line immunotherapy versus docetaxel. The model used outcomes data from randomized clinical trials (RCTs) and drug acquisition costs from the United States. Thereafter, we used epidemiologic data to estimate the economic impact of the treatment. RESULTS: We included four RCTs (2 with nivolumab, 1 with pembrolizumab, and 1 with atezolizumab). The incremental quality-adjusted life year (QALY) for nivolumab was 0.417 among squamous tumors and 0.287 among non-squamous tumors and the incremental cost-effectiveness ratio (ICER) were $155 605 and $187 685, respectively. The QALY gain in the base case for atezolizumab was 0.354 and the ICER was $215 802. Compared with treating all patients, the selection of patients by PD-L1 expression improved incremental QALY by up to 183% and decreased the ICER by up to 65%. Pembrolizumab was studied only in patients whose tumors expressed PD-L1. The QALY gain was 0.346 and the ICER was $98 421. Patient selection also reduced the budget impact of immunotherapy. CONCLUSION: The use of PD-L1 expression as a biomarker increases cost-effectiveness of immunotherapy but also diminishes the number of potential life-years saved.


Asunto(s)
Antineoplásicos Inmunológicos/uso terapéutico , Antígeno B7-H1/metabolismo , Biomarcadores de Tumor/metabolismo , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Carcinoma de Pulmón de Células no Pequeñas/metabolismo , Análisis Costo-Beneficio , Inmunoterapia/métodos , Neoplasias Pulmonares/tratamiento farmacológico , Antineoplásicos Inmunológicos/economía , Presupuestos , Carcinoma de Pulmón de Células no Pequeñas/fisiopatología , Costos de los Medicamentos , Humanos , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/fisiopatología , Años de Vida Ajustados por Calidad de Vida , Análisis de Supervivencia , Resultado del Tratamiento
3.
Clin Exp Med ; 23(2): 333-346, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35377095

RESUMEN

The role of platelet function indices-platelet count (PLT), mean platelet volume (MPV), platelet distribution width (PDW), plateletcrit (PCT), immature platelet fraction (IPF), and platelet mass index (PMI)-in psoriasis is uncertain. This systematic review and meta-analysis aimed to evaluate the association of these platelet biomarkers with both presence and severity of psoriasis. We searched MEDLINE (Ovid), Embase (Ovid), and the Cochrane Library from inception to November 2021. To evaluate the association of platelet function indices and psoriasis, we recorded mean differences (MD) and 95% confidence intervals (CI) as well as correlation coefficients (r) for each included study, and generated summary estimates using random-effects inverse-variance modelling. We screened 1,079 unique studies, and included 33 studies with 6724 patients in the quantitative analyses. Compared with controls, patients with psoriasis had higher PLT (MD 12.86 × 109/L, 95% CI 6.34-19.39, p < 0.001), MPV (MD 0.61fL, 95% CI 0.31-0.92, p < 0.001), and PCT (MD 0.05%, 95% CI 0.01-0.09, p = 0.010), but similar PDW (MD 0.16%, 95% CI -0.46-0.79, p = 0.610). Psoriasis Area and Severity Index (PASI) was weakly correlated with PLT (r 0.17, 95% CI 0.06-0.28, p = 0.003), MPV (r 0.36, 95% CI 0.22-0.49, p < 0.001), and PDW (r 0.17, 95% CI 0.08-0.26, p < 0.001). Study numbers were insufficient to judge the relationship of IPF and PMI with psoriasis presence, or PCT, IPF, and PMI with psoriasis severity. In summary, PLT, MPV, and PCT are significantly elevated in patients with psoriasis, and PLT, MPV, and PDW are weakly correlated with PASI. Future studies are needed to evaluate the independent diagnostic and prognostic potentials of these biomarkers in patients with psoriasis.


Asunto(s)
Plaquetas , Volúmen Plaquetario Medio , Humanos , Recuento de Plaquetas , Pronóstico , Biomarcadores
6.
J Endocrinol Invest ; 34(4): 296-9, 2011 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-20585202

RESUMEN

Fifteen children and adolescents (4 male) with a median age of 5.4 yr (range 1.2 -13.6 yr) were entered into a screening protocol to identify lesions of von Hippel-Lindau (VHL) disease. Fourteen had an affected first-degree relative and one had a previous VHL lesion. Screening during the period of 2000 to 2008 followed published guidelines and consisted of measurement of urinary catecholamines, adrenal and renal imaging and ophthalmological and central nervous system examinations and imaging. Screening identified 8 VHL lesions in 6 asymptomatic patients with confirmed genetic mutations. Five patients had elevated urinary noradrenaline excretion and in each case the presence of a pheochromocytoma was identified on adrenal magnetic resonance imagin scan. In one patient a left-sided tumor was identified 1 yr after a right-sided tumor had been removed. In a sixth patient a retinal capillary hemangioma and a cerebellar hemangioblastoma were identified. Patient compliance with the screening protocol was variable reflecting its time-intensive nature. A formal screening programme for this at-risk population of pediatric patients, despite being intensive, can identify VHL lesions during a pre-morbid phase and may thus have a beneficial impact on prognosis in this serious disorder.


Asunto(s)
Tamizaje Masivo , Cooperación del Paciente , Enfermedad de von Hippel-Lindau/diagnóstico , Enfermedad de von Hippel-Lindau/patología , Adolescente , Neoplasias de las Glándulas Suprarrenales/diagnóstico , Neoplasias de las Glándulas Suprarrenales/genética , Neoplasias de las Glándulas Suprarrenales/patología , Neoplasias de las Glándulas Suprarrenales/cirugía , Catecolaminas/orina , Neoplasias Cerebelosas/diagnóstico , Neoplasias Cerebelosas/genética , Neoplasias Cerebelosas/patología , Neoplasias Cerebelosas/cirugía , Niño , Preescolar , Femenino , Hemangioma/diagnóstico , Hemangioma/genética , Hemangioma/patología , Hemangioma/cirugía , Humanos , Lactante , Neoplasias Renales/diagnóstico , Neoplasias Renales/genética , Neoplasias Renales/patología , Neoplasias Renales/cirugía , Masculino , Feocromocitoma/diagnóstico , Feocromocitoma/genética , Feocromocitoma/patología , Feocromocitoma/cirugía , Neoplasias de la Retina/diagnóstico , Neoplasias de la Retina/genética , Neoplasias de la Retina/patología , Neoplasias de la Retina/cirugía , Estudios Retrospectivos , Resultado del Tratamiento , Enfermedad de von Hippel-Lindau/genética , Enfermedad de von Hippel-Lindau/cirugía
7.
Eur J Endocrinol ; 156(4): 477-82, 2007 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-17389463

RESUMEN

BACKGROUND/OBJECTIVE: Pituitary radiotherapy (RT) is an effective second-line treatment for paediatric Cushing's disease (CD). Although the short-term effects of pituitary RT are well documented, there are less data on possible long-term sequelae. We report the long-term anterior pituitary function in a cohort of paediatric CD patients treated with pituitary RT. PATIENTS AND METHODS: Between 1983 and 2006, 12 paediatric CD patients (10 males and 2 females) of mean age 11.4 years at diagnosis (range 6.4-17.4) underwent second-line pituitary RT (45 Gy in 25 fractions), following unsuccessful transsphenoidal surgery. Out of 12, 11 patients were cured by RT (cure interval 0.13-2.86 years) defined by mean serum cortisol of <150 nmol/l on 5-point day curve and midnight sleeping cortisol of <50 nmol/l. Long-term data are available for six male patients, who received RT at the age of 7.0-17.6 years. The mean follow-up from the completion of RT was 10.5 years (6.6-16.5). RESULTS: At a mean of 1.0 year (0.11-2.54) following RT, GH deficiency (peak GH <1-17.9 mU/l) was present in five out of six patients. On retesting at a mean of 9.3 years (7.6-11.3) after RT, three out of four patients were GH sufficient (peak GH 19.2-50.4 mU/l). Other anterior pituitary functions including serum prolactin in five out of six patients were normal on follow-up. All the six patients had testicular volumes of 20-25 ml at the age of 14.5-28.5 years. CONCLUSION: This series of patients illustrates the absence of serious long-term pituitary deficiency after RT and emphasises the importance of continued surveillance.


Asunto(s)
Hipersecreción de la Hormona Adrenocorticotrópica Pituitaria (HACT)/metabolismo , Hipersecreción de la Hormona Adrenocorticotrópica Pituitaria (HACT)/radioterapia , Adenohipófisis/metabolismo , Irradiación Hipofisaria , Adolescente , Hormona Adrenocorticotrópica/sangre , Niño , Estudios de Seguimiento , Gonadotropinas/sangre , Hormona de Crecimiento Humana/deficiencia , Hormona de Crecimiento Humana/metabolismo , Humanos , Hidrocortisona/sangre , Masculino , Hipersecreción de la Hormona Adrenocorticotrópica Pituitaria (HACT)/sangre , Hipersecreción de la Hormona Adrenocorticotrópica Pituitaria (HACT)/fisiopatología , Neurohipófisis/metabolismo , Pubertad , Testículo/crecimiento & desarrollo , Tirotropina/sangre
8.
J Endocrinol Invest ; 30(5): 388-92, 2007 May.
Artículo en Inglés | MEDLINE | ID: mdl-17598970

RESUMEN

Hyperthyroidism is rare in early childhood and most commonly caused by Graves' disease. We report 14 children (4 boys, 10 girls) aged 3.4-7.5 yr. At diagnosis, all patients had weight loss, hyperkinetic activity, tachycardia, difficulty sleeping, and poor concentration and 11 presented with proptosis. Four patients developed long-term neuropsychological problems. There was a family history in 7 cases. All patients had goiters, clinically assessed to be large and diffuse in 21%, medium-sized in 43%, and small in 36%. At diagnosis, height was increased with median (range) height; 1.25 standard deviation score (SDS) (-0.2-5.24) and body mass index (BMI) was decreased; -0.48 SDS (-1.65-1.26). Height and BMI SDS values were statistically different (p<0.032) Bone age was advanced in 4 of 5 children, who had assessments. Total or free T4 levels were elevated and TSH was undetectable. Ninety percent of patients (12/14) had positive thyroid peroxidase autoantibodies, mean level 680 IU/ml (range 50-1347). Initial treatment was with antithyroid medication using carbimazole; median dose 0.75 mg/kg/day (no.=13) or propylthiouracyl 15 mg/kg/day (no.=1). T4 was added in 6 patients. Normalisation of serum T4 occurred at 4 months (1- 9) and TSH at 7 months (3-24) after start of therapy. Treatment was discontinued after a minimum of 2 yr in 11 patients, relapse occurring in 9. Median duration of total therapy was 58 months (18-132). During adolescence, 4 patients had curative therapy by surgery (no.=2) or radioiodine (no.=2). In conclusion, disturbance of growth, behavioral difficulties and infrequent spontaneous remission are key features of Graves' disease in early childhood.


Asunto(s)
Enfermedad de Graves/complicaciones , Enfermedad de Graves/fisiopatología , Edad de Inicio , Antitiroideos/administración & dosificación , Trastorno por Déficit de Atención con Hiperactividad/etiología , Carbimazol/administración & dosificación , Niño , Preescolar , Exoftalmia/etiología , Femenino , Enfermedad de Graves/tratamiento farmacológico , Enfermedad de Graves/inmunología , Trastornos del Crecimiento/etiología , Humanos , Hipercinesia/etiología , Yoduro Peroxidasa/inmunología , Masculino , Propiltiouracilo/administración & dosificación , Recurrencia , Estudios Retrospectivos , Trastornos del Sueño-Vigilia/etiología , Taquicardia/etiología , Tirotropina/sangre , Tiroxina/sangre , Pérdida de Peso
9.
J Clin Endocrinol Metab ; 70(5): 1280-4, 1990 May.
Artículo en Inglés | MEDLINE | ID: mdl-2186056

RESUMEN

A 15-yr-old, apparently male, patient presented with a 2-yr history of gynecomastia and poor genital development. A normally formed, but small, penis with a phallic urethra was present, and testes were impalpable. The karyotype was 46,XX, and at laparotomy a uterus, Fallopian tubes, and ovaries were found, but there was no testicular tissue. The mother had had regular periods ever since menarche at 14 yr. She had complained of hirsutism since the birth of the child, and on examination 15 yr later had marked clitoromegaly. Serum androgens were elevated: testosterone, 4.5 nmol/L (normal, 0.5-3); dehydroepiandrosterone sulfate, 18 mumol/L (normal, 3-12); and androstenedione, 35 nmol/L (normal, 3-8). All failed to suppress with dexamethasone. Abdominal computed tomographic scan revealed a 9 X 6-cm mass in the position of the left adrenal gland. This was removed at laparotomy and found to be an adrenocortical tumor. Postoperatively, the androgens returned to normal. Virilization of a female fetus due to androgens secreted by a maternal adrenal tumor has only been described three times previously, and the presentation has never been delayed so long.


Asunto(s)
Neoplasias de las Glándulas Suprarrenales/complicaciones , Trastornos del Desarrollo Sexual/etiología , Síndromes Paraneoplásicos Endocrinos/complicaciones , Complicaciones Neoplásicas del Embarazo/sangre , 17-alfa-Hidroxiprogesterona , Adolescente , Neoplasias de las Glándulas Suprarrenales/sangre , Adulto , Andrógenos/sangre , Trastornos del Desarrollo Sexual/sangre , Femenino , Humanos , Hidroxiprogesteronas/sangre , Masculino , Intercambio Materno-Fetal/fisiología , Síndromes Paraneoplásicos Endocrinos/sangre , Embarazo
10.
J Clin Endocrinol Metab ; 86(7): 2989-92, 2001 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-11443156

RESUMEN

Pegvisomant is a GH receptor antagonist and highly efficacious new treatment for acromegaly. The two isoenzymes of 11beta-hydroxysteroid dehydrogenase are responsible for the interconversion of cortisol and its inactive metabolite cortisone. We demonstrated previously that the type I isoform, which is principally responsible for conversion of cortisone to cortisol, is partially inhibited by GH. The net activity of the enzyme can be measured by analysis of the urinary ratio of 11-hydroxy/11-oxo cortisol metabolites or of the urinary ratio of tetrahydrocortisol/tetrahydrocortisone [(tetrahydrocortisol + 5alpha-tetrahydrocortisol)/tetrahydrocortisone]. We studied the influence of pegvisomant on cortisol metabolism in patients with active acromegaly. Seven patients (four women and three men; median age, 58 yr; range, 39-72) were studied at baseline and again after a mean of 46 weeks of treatment. The mean insulin-like growth factor I (IGF-I) level at baseline fell from 939.7 +/- 271.1 to 346.9 +/- 379.0 ng/mL on 20 mg/day pegvisomant. The 11-hydroxy/11-oxo ratio increased from a pretreatment mean value of 0.61 +/- 0.18 to 0.88 +/- 0.20 (P < 0.02) and when the six patients in whom serum IGF-I normalized were considered separately, the change was from 0.62 +/- 0.19 to 0.90 +/- 0.21 (P < 0.04). The tetrahydrocortisols/tetrahydrocortisone ratio increased from a pretreatment mean value of 0.64 +/- 0.21 to 0.98 +/- 0.26 (P < 0.02) and in the six patients in whom serum IGF-I normalized, the ratio rose from 0.66 +/- 0.23 to 1.01 +/- 0.26 (P < 0.04). These data 1) indicate that blockade of GH action with pegvisomant in patients with acromegaly is associated with reversal of the inhibition of 11beta-hydroxysteroid dehydrogenase and correction of cortisol metabolism, and 2) suggest that in active acromegaly, cortisol clearance is accelerated and that this is reversed by successful treatment. This is further evidence of the efficacy of pegvisomant in the management of acromegaly and has important implications for determining optimum glucocorticoid replacement.


Asunto(s)
Acromegalia/tratamiento farmacológico , Acromegalia/metabolismo , Hormona de Crecimiento Humana/análogos & derivados , Hormona de Crecimiento Humana/uso terapéutico , Hidrocortisona/metabolismo , Receptores de Somatotropina/antagonistas & inhibidores , 11-beta-Hidroxiesteroide Deshidrogenasas , Adulto , Anciano , Método Doble Ciego , Femenino , Humanos , Hidrocortisona/orina , Hidroxiesteroide Deshidrogenasas/antagonistas & inhibidores , Factor I del Crecimiento Similar a la Insulina/análisis , Masculino , Persona de Mediana Edad , Tetrahidrocortisol/orina , Tetrahidrocortisona/orina
11.
J Clin Endocrinol Metab ; 68(5): 932-7, 1989 May.
Artículo en Inglés | MEDLINE | ID: mdl-2523898

RESUMEN

The relationships between plasma insulin, insulin-like growth factor I (IGF-I) and dehydroepiandrosterone sulfate (DHEAS) concentrations in normal subjects have not been defined. We performed iv glucose tolerance tests on 102 normal subjects, aged 5-20 yr. The subjects were divided into 4 groups according to pubertal stage (Tanner): A, stage 1 (n = 22); B, stages 2 and 3 (n = 17); C, stages 4 and 5 (n = 20); and D, adult, greater than 17 yr (n = 43). The basal plasma IGF-I and insulin concentrations and incremental 0-60 min insulin areas in response to glucose rose significantly throughout puberty (P less than 0.001 for all parameters) and declined to prepubertal levels by the third decade of life. There was a strong positive correlation between log fasting plasma insulin vs. log plasma IGF-I (r = 0.625; P less than 0.001) and log incremental 0-60 min insulin areas vs. log plasma IGF-I (r = 0.572; P less than 0.001). Plasma DHEAS concentrations were measured in groups A-C (n = 59); these also rose throughout puberty. There was strong correlations between log plasma DHEAS and log basal or stimulated (incremental 0-60 min areas) insulin responses (P less than 0.001). To assess the relationship between plasma DHEAS and insulin before puberty, we analyzed the data from group A separately. Plasma DHEAS concentrations tended to be higher in children 9 yr of age or older than in those less than 9 yr old, whereas basal and stimulated plasma insulin levels were similar. We found no correlation between log plasma insulin (fasting or stimulated responses) and log plasma DHEAS concentrations in group A (P greater than 0.05). In conclusion, we found a strong relationship between plasma insulin and IGF-I throughout childhood and puberty and during adult life. This finding suggests that insulin may be important for normal growth during childhood. There was no correlation between plasma insulin and DHEAS concentrations in prepubertal children, which suggests that adrenarche does not influence insulin levels.


Asunto(s)
Envejecimiento/sangre , Deshidroepiandrosterona/análogos & derivados , Factor I del Crecimiento Similar a la Insulina/sangre , Insulina/sangre , Somatomedinas/sangre , Adolescente , Adulto , Factores de Edad , Niño , Preescolar , Deshidroepiandrosterona/sangre , Sulfato de Deshidroepiandrosterona , Femenino , Prueba de Tolerancia a la Glucosa , Humanos , Masculino , Persona de Mediana Edad
12.
J Clin Endocrinol Metab ; 83(10): 3542-4, 1998 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-9768661

RESUMEN

We report the emergency and prolonged use of etomidate to control circulating cortisol levels in a patient with Cushing's syndrome secondary to ectopic ACTH production from a pancreatic islet cell tumor. Duodenal perforation and peritonitis complicated an episode of salmonella septicemia, precluding the use of conventional oral medical adrenolytic therapy. Endogenous cortisol secretion was abolished by parenteral etomidate, allowing serum cortisol levels to be controlled with an iv infusion of hydrocortisone over an 8-week period in intensive care before definitive pancreatic surgery.


Asunto(s)
Síndrome de Cushing/sangre , Servicios Médicos de Urgencia , Etomidato/administración & dosificación , Hidrocortisona/sangre , Peritonitis/complicaciones , Adenoma de Células de los Islotes Pancreáticos/metabolismo , Adenoma de Células de los Islotes Pancreáticos/cirugía , Hormona Adrenocorticotrópica/metabolismo , Adulto , Síndrome de Cushing/complicaciones , Síndrome de Cushing/etiología , Etomidato/uso terapéutico , Humanos , Hidrocortisona/antagonistas & inhibidores , Hidrocortisona/uso terapéutico , Inyecciones Intravenosas , Masculino , Neoplasias Pancreáticas/metabolismo , Neoplasias Pancreáticas/cirugía , Cuidados Preoperatorios
13.
J Clin Endocrinol Metab ; 83(9): 3083-8, 1998 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-9745407

RESUMEN

Menstrual irregularity is a common complaint at presentation in women with Cushing's syndrome, although the etiology has been little studied. We have assessed 45 female patients (median age, 32 yr; range, 16-41 yr) with newly diagnosed pituitary-dependent Cushing's syndrome. Patients were subdivided into 4 groups according to the duration of their menstrual cycle: normal cycles (NC; 26-30 days), oligomenorrhea (OL; 31-120 days), amenorrhea (AM; > 120 days), and polymenorrhea (PM; < 26 days). Blood was taken at 0900 h for measurement of LH, FSH, PRL, testosterone, androstenedione, dehydroepiandrosterone sulfate, estradiol (E2), sex hormone-binding globulin (SHBG), and ACTH; cortisol was sampled at 0900, 1800, and 2400 h. The LH and FSH responses to 100 micrograms GnRH were analyzed in 23 patients. Statistical analysis was performed using the nonparametric Mann-Whitney U and Spearman tests. Only 9 patients had NC (20%), 14 had OL (31.1%), 15 had AM (33.3%), and 4 had PM (8.8%), whereas 3 had variable cycles (6.7%). By group, AM patients had lower serum E2 levels (median, 110 pmol/L) than OL patients (225 pmol/L; P < 0.05) or NC patients (279 pmol/L; P < 0.05), and higher serum cortisol levels at 0900 h (800 vs. 602 and 580 nmol/L, respectively; P < 0.05) and 1800 h (816 vs. 557 and 523 nmol/L, respectively; P < 0.05) and higher mean values from 6 samples obtained through the day (753 vs. 491 and 459 nmol/L, respectively; P < 0.05). For the whole group of patients there was a negative correlation between serum E2 and cortisol at 0900 h (r = -0.50; P < 0.01) and 1800 h (r = -0.56; P < 0.01) and with mean cortisol (r = -0.46; P < 0.05). No significant correlation was found between any serum androgen and E2 or cortisol. The LH response to GnRH was normal in 43.5% of the patients, exaggerated in 52.1%, and decreased in 4.4%, but there were no significant differences among the menstrual groups. No differences were found in any other parameter. In summary, in our study 80% of patients with Cushing's syndrome had menstrual irregularity, and this was most closely related to serum cortisol rather than to circulating androgens. Patients with AM had higher levels of cortisol and lower levels of E2, while the GnRH response was either normal or exaggerated. Our data suggest that the menstrual irregularity in Cushing's disease appears to be the result of hypercortisolemic inhibition of gonadotropin release acting at a hypothalamic level, rather than raised circulating androgen levels.


Asunto(s)
Andrógenos/sangre , Síndrome de Cushing/complicaciones , Hidrocortisona/sangre , Trastornos de la Menstruación/etiología , Adolescente , Adulto , Androstenodiona/sangre , Síndrome de Cushing/sangre , Sulfato de Deshidroepiandrosterona/sangre , Estradiol/sangre , Femenino , Hormona Folículo Estimulante/sangre , Humanos , Hormona Luteinizante/sangre , Prolactina/sangre , Valores de Referencia , Globulina de Unión a Hormona Sexual/análisis , Testosterona/sangre
14.
J Clin Endocrinol Metab ; 84(7): 2489-95, 1999 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-10404825

RESUMEN

GH secretagogues (GHSs) act via specific receptors in the hypothalamus and the pituitary gland to release GH. GHSs also stimulate the hypothalamo-pituitary-adrenal (HPA) axis via central mechanisms probably involving CRH or arginine vasopressin (AVP). We studied the effects of hexarelin, CRH, and desmopressin, an AVP analog, on the stimulation of the HPA axis in 15 healthy young male volunteers. Circulating ACTH, cortisol, GH and PRL concentrations were measured for 2 h after the injection of hexarelin, CRH, or desmopressin alone and the combination of hexarelin plus CRH or hexarelin plus desmopressin. Symptoms during the tests were assessed by visual analog scales. Hexarelin significantly increased ACTH and cortisol release (area under the curve, 3,444+/-696 ng/L x 125 min and 45,844+/-2,925 nmol/L x 125 min, respectively), and this effect was augmented by the addition of CRH in a dose that on its own produces maximal stimulation (6,580+/-1,572 ng/mL x 125 min and 63,170+/-2,616 nmol/L x 125 min; P = 0.01 and 0.001, respectively), but was not influenced by the addition of desmopressin (3,540+/-852 ng/mL x 125 min and 35,319+/-3,252 nmol/L x 125 min; not significant). CRH on its own caused similar or slightly higher ACTH and cortisol release than hexarelin alone. Desmopressin given alone elicited a rapid rise in circulating ACTH and cortisol, but its effects were less than those of any other treatment and were not augmented by hexarelin. Hexarelin also caused significant GH and PRL release, but these effects were not influenced by the coadministration of CRH or desmopressin. Visual analog scales showed an acute small increment in appetite with hexarelin. Our data suggest that the effect of GHSs on the HPA axis involve at least in part the stimulation of AVP release. In summary, we have shown that in healthy male volunteers, the effect of hexarelin on the HPA axis does not involve CRH, but may occur through the stimulation of AVP release.


Asunto(s)
Glándulas Suprarrenales/efectos de los fármacos , Arginina Vasopresina/metabolismo , Sustancias de Crecimiento/farmacología , Hipotálamo/efectos de los fármacos , Oligopéptidos/farmacología , Hipófisis/efectos de los fármacos , Glándulas Suprarrenales/metabolismo , Hormona Adrenocorticotrópica/metabolismo , Adulto , Hormona Liberadora de Corticotropina/farmacología , Desamino Arginina Vasopresina/farmacología , Método Doble Ciego , Hormona de Crecimiento Humana/metabolismo , Humanos , Hidrocortisona/metabolismo , Hipotálamo/metabolismo , Masculino , Hipófisis/metabolismo , Prolactina/metabolismo
15.
J Endocrinol ; 118(1): 161-5, 1988 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-3411281

RESUMEN

Blood was taken from three healthy female and three healthy male volunteers every 20 s for 15 min. The serum level of oestradiol was measured and the pattern of variation assessed by a cusum plot of the sequential data, by autocorrelation of the detrended serial data, and by looking for pulses. In two cases the variation in oestradiol values was greater than that which could be attributed to variation in the assay. Both these subjects showed a significant overall change in values during the sampling period (an increase and a decrease). There was no trend in the remaining four subjects. In two of the six subjects there was significant autocorrelation of detrended sequential levels. Defining a 'pulse' as three times the assay coefficient of variation no more pulses were identified than was expected from random fluctuations. By frequency analysis the two subjects with significant autocorrelation showed periodic fluctuations of approximately 70/h and 9/h respectively. It is apparent that both the rate of sampling and the method of analysis greatly influence the evaluation of pulsatile release of oestradiol.


Asunto(s)
Recolección de Muestras de Sangre/métodos , Estradiol/sangre , Adulto , Femenino , Humanos , Masculino , Tasa de Secreción
16.
J Endocrinol ; 128(1): 161-8, 1991 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-1705572

RESUMEN

Insulin-like growth factor-binding protein-1 (IGFBP-1) has been purified from amniotic fluid by anion exchange, hydrophobic interaction and gel filtration chromatography. The overall recovery of the purification process was 12.2%. The purified IGFBP-1 yielded a single band on SDS-PAGE gel but showed two bands (34 kDa and 68 kDa) on Western blot under non-reducing conditions. Polyclonal antisera were raised by immunization of sheep using the purified IGFBP-1. The best antiserum bound 50% of 125I-labelled IGFBP-1 at a final dilution of 1:500,000. A radioimmunoassay for IGFBP-1 was developed. This assay had a minimum detection limit of 5 micrograms/l, and was used to determine serum levels in non-pregnant and pregnant women. There was no cross-reaction with a wide variety of materials tested. Serum IGFBP-1 levels in non-pregnant individuals (33 +/- 16 (S.D.) micrograms/l) were found to be significantly lower than those in the second (96 +/- 64 micrograms/l) and third trimesters (95 +/- 60 micrograms/l) of pregnant women. During pregnancy, circulating IGFBP-1 levels increased rapidly in the first trimester and reached a peak at 12-13 weeks of gestation (107 +/- 75 micrograms/l). The level then remained at 80 +/- 53 to 103 +/- 70 micrograms/l until term.


Asunto(s)
Proteínas Portadoras/aislamiento & purificación , Embarazo/sangre , Somatomedinas/aislamiento & purificación , Adolescente , Adulto , Líquido Amniótico/química , Proteínas Portadoras/sangre , Cromatografía en Gel , Cromatografía por Intercambio Iónico , Electroforesis en Gel de Poliacrilamida , Femenino , Humanos , Proteínas de Unión a Factor de Crecimiento Similar a la Insulina , Segundo Trimestre del Embarazo , Tercer Trimestre del Embarazo , Radioinmunoensayo , Somatomedinas/metabolismo
17.
J Endocrinol ; 162(1): 155-61, 1999 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-10396032

RESUMEN

Early descriptions of in vitro ACTH bioassays all emphasised the need to use extracted plasma samples due to interference by an unidentified component. The aim of these studies was to elucidate the effects of whole plasma on ACTH steroidogenic activity in vitro and to identify the responsible factor. A sensitive in vitro dispersed bovine adrenocortical cell bioassay was established. The addition of 10% ACTH-depleted human pooled plasma to the incubation media resulted in basal steroidogenesis equivalent to that achieved with 10(-9) M ACTH1-24 and potentiated the steroidogenic activity of 10(-9) M ACTH1-24 by 7.8-fold. This potentiation was dependent on the concentration of both ACTH and plasma in the media, but did not result from the mitogenic effect of plasma. A pituitary source was excluded and the potentiating activity was not extractable by Vycor glass. Column chromatography demonstrated two peaks of activity corresponding to molecular weights of 650 and 220x10(3) Da. These peaks did not correspond to the plasma binding of 125I-ACTH which resulted from non-specific binding to albumin. Lipoprotein-deficient serum had no effect on either basal or ACTH-stimulated steroidogenesis, but both were restored by the addition of purified lipoproteins. However, novel findings demonstrated a differential effect of low (LDL) and high (HDL) density lipoproteins on basal and ACTH-stimulated steroid production; thus, LDL exerted a greater effect on the former, whilst HDL potentiated the steroidogenic activity of added ACTH more than LDL. The addition of the lipoproteins to lipoprotein-deficient serum restored its basal and ACTH potentiating effects, the cholesterol concentrations of the chromatographic fractions exactly paralleling their ACTH potentiating effect. These findings suggest that not only are lipoproteins the plasma factor(s) which potentiates ACTH steroidogenic activity in in vitro bioassays, but also that they exert differential effects on basal and ACTH-stimulated steroid production.


Asunto(s)
Hormona Adrenocorticotrópica/farmacología , Plasma/fisiología , Esteroides/biosíntesis , Animales , Bovinos , HDL-Colesterol/farmacología , LDL-Colesterol/farmacología , Sinergismo Farmacológico , Humanos , Peso Molecular
18.
Dis Markers ; 6(2): 119-25, 1988 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-3402176

RESUMEN

An analysis of 89 male sibling pairs from multicase rheumatoid arthritis families demonstrated an association between HLA and serum testosterone levels. In sibling pairs that were haplotype identical, the mean inter-pair difference in testosterone level expressed as a log ratio was significantly less than sibling pairs sharing neither haplotype (p = 0.03). This difference was independent of the RA status of the pairs. These results suggest the presence of a gene(s) controlling testosterone levels linked to the Major Histocompatibility Complex (MHC) on chromosome 6. These findings may aid understanding of the roles of HLA antigens and sex hormones in the susceptibility to RA and other autoimmune disease.


Asunto(s)
Antígenos HLA/genética , Haplotipos , Testosterona/genética , Artritis Reumatoide/sangre , Artritis Reumatoide/genética , Ligamiento Genético , Antígenos HLA/análisis , Humanos , Masculino , Testosterona/sangre
19.
J Clin Pathol ; 50(5): 379-83, 1997 May.
Artículo en Inglés | MEDLINE | ID: mdl-9215119

RESUMEN

AIM: To analyse critically a protocol for the investigation of girls presenting with virilisation in childhood. METHODS: Twenty five girls aged 1.6-8.7 years with features of virilisation were evaluated. Twenty four had presented with pubic hair, eight with auxilliary hair, seven with facial acne, four with clitoromegaly, and 10 with tall stature. They underwent clinical assessment (height, weight, height velocity, staging of puberty, physical examination for acne, body odour, and clitoromegaly) and laboratory assessment comprising basal concentrations of cortisol, 17 OH-progesterone (17 OHP), androstenedione, dehydroepiandrosteronesulphate (DHEAS), testosterone, and oestradiol. The above steroids were also measured during the short synacthen test (0.25 mg intramuscularly) in 16 subjects and low dose dexamethasone suppression tests (0.5 mg at six hourly intervals over 48 hours). Pelvic ultrasound, computed tomography and magnetic resonance imaging of adrenals were carried out when the biochemical findings suggested that there might be an autonomous source of androgen secretion. RESULTS: Clinical and laboratory assessments differentiated the patients into three diagnostic categories: adrenarche (18 cases), congenital adrenal hyperplasia (five cases), and adrenocortical tumour (two cases). The last had elevated concentrations of DHEAS, 1.5 and 19.1 mumol/l (normal value < 0.5 mumol/l), androstenedione, 24.6 and 21.8 nmol/l (normal < 1 nmol/l), and testosterone, 4.5 and 2.4 nmol/l (normal < 0.8 nmol/l), with none suppressing on dexamethasone suppression. Congenital adrenal hyperplasia subjects had elevated basal serum concentrations of 17 OHP (n = 4): 250, 140, 14, and 14.1 nmol/l (normal < 10 nmol/l) and elevated peak values of 17 OHP after synacthen (n = 3): 76, 179.5, and 175 nmol/l. Adrenarche patients had elevated basal concentrations of DHEAS (median: 2.3 mumol/l; n = 17) and androstenedione (median 2.6 nmol/l; n = 17). Nine patients also had elevated basal serum testosterone concentrations (median 0.9 nmol/l). Peak values of 17 OHP after synacthen were significantly different from baseline (n = 12) and were < 50% of the lowest value in congenital adrenal hyperplasia. Serum DHEAS, androstenedione, and testosterone suppressed following dexamethasone suppression (n = 16), thereby distinguishing adrenarche patients from adrenal tumour patients. Clinical details did not distinguish patients, except for clitoromegaly which was present only in the tumour and congenital adrenal hyperplasia patients. CONCLUSIONS: This protocol proved useful and practical in cases of virilisation presenting particular diagnostic difficulty.


Asunto(s)
Virilismo/etiología , Neoplasias de la Corteza Suprarrenal/sangre , Neoplasias de la Corteza Suprarrenal/complicaciones , Neoplasias de la Corteza Suprarrenal/diagnóstico , Hiperplasia Suprarrenal Congénita/sangre , Hiperplasia Suprarrenal Congénita/complicaciones , Hiperplasia Suprarrenal Congénita/diagnóstico , Andrógenos/sangre , Niño , Preescolar , Protocolos Clínicos , Cosintropina , Deshidroepiandrosterona/sangre , Dexametasona , Diagnóstico Diferencial , Femenino , Humanos , Lactante , Virilismo/sangre
20.
Obstet Gynecol ; 57(2): 215-9, 1981 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-7465127

RESUMEN

Non-protein-bound (free) cortisol in plasma is that fraction of the total plasma cortisol concentration that is generally regarded as biologically active. The concentration of free cortisol in cord vein plasma obtained at delivery was found to be related closely to the total cortisol concentration. After vaginal delivery following spontaneous onset of labor the free cortisol concentration in cord blood was not significantly different from that measured following induced onset of labor. The free cortisol concentration in the cord blood correlated significantly with the duration of the second stage of labor. These changes in the free cortisol concentration in cord plasma, rather than constituting a primary event in the onset of labor, may reflect the stress of vaginal delivery on the fetus.


Asunto(s)
Parto Obstétrico , Sangre Fetal/análisis , Hidrocortisona/sangre , Cesárea , Femenino , Humanos , Trabajo de Parto Inducido , Trabajo de Parto , Embarazo
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