Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Resultados 1 - 8 de 8
Filtrar
1.
Reprod Biomed Online ; 24(3): 364-74, 2012 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-22285243

RESUMEN

Follistatin, an inhibitor of activin A, has key regulatory roles in the female reproductive tract. Follistatin has two splice variants: FST288, largely associated with cell surfaces, and FST315, the predominant circulating form. The mechanism regulating uterine expression of these variants is unknown. Quantitative RT-PCR was used to measure expression of follistatin splice variants (Fst288, Fst315), the activin bA subunit (Inhba) and the inhibin a subunit (Inha) in uterine tissues during early pregnancy (days 1­4, preimplantation) and in response to exogenous 17b-oestradiol (single s.c. injection) and progesterone (three daily s.c. injections) in ovariectomized mice. Uterine Fst288, Fst315 and Inhba expression increased during early pregnancy, with greater increases in Fst315 relative to Fst288 suggesting differential regulation of these variants. Fst288, Fst315, Inhba and Inha all increased in response to progesterone treatment. Fst288, but not Fst315, mRNA decreased in response to 17b-oestradiol treatment, whereas Inhba increased. A comparison of the absolute concentrations of uterine follistatin mRNA using crossing thresholds indicated that both variants were more highly expressed in early pregnancy in contrast to the hormone treatment models. It is concluded that progesterone regulates uterine expression of both follistatin variants, as well as activin A, during early pregnancy in the mouse uterus


Asunto(s)
Folistatina/metabolismo , Regulación de la Expresión Génica/efectos de los fármacos , Progesterona/farmacología , Útero/efectos de los fármacos , Animales , Estradiol/farmacología , Femenino , Folistatina/química , Folistatina/genética , Subunidades beta de Inhibinas/genética , Subunidades beta de Inhibinas/metabolismo , Inhibinas/genética , Inhibinas/metabolismo , Ratones , Embarazo , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , ARN Mensajero/metabolismo , Reacción en Cadena en Tiempo Real de la Polimerasa , Útero/metabolismo
2.
J Clin Oncol ; 1(10): 627-34, 1983 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-6583316

RESUMEN

Marrow cytogenetic and granulocyte-macrophage colony formation (CFU-GM) studies were performed on 34 previously untreated patients with documented myelodysplastic syndromes seen between January 1978 and June 1982. All patients were managed without chemotherapy until progression to acute leukemia was observed. All 10 patients with exclusively abnormal marrow metaphases developed acute leukemia (100%) while only one (7%) of 14 patients with solely normal marrow metaphases subsequently developed leukemia (p less than 0.001). Three (42%) of the seven patients with both normal and abnormal marrow metaphases developed acute leukemia. Fifteen (86%) of the 19 patients with either large cluster or no growth patterns developed acute leukemia while only two (13%) of 15 patients with either small cluster or colony forming growth patterns developed acute leukemia (p less than 0.001). Abnormal marrow cytogenetic status correlated with abnormal marrow CFU-GM growth pattern (p less than 0.05). Analysis of CFU-GM sensitivity to inhibition by prostaglandin E was performed in 12 patients. Nine patients showed CFU-GM refractoriness to inhibition by prostaglandin E. Seven of these patients eventually developed leukemia. Three patients had CFU-GMs which were initially sensitive to prostaglandin E inhibition. In these three patients, a loss of CFU-GM sensitivity to prostaglandin E was observed prior to their progression to morphologically identifiable acute leukemia.


Asunto(s)
Médula Ósea/ultraestructura , Aberraciones Cromosómicas , Ensayo de Unidades Formadoras de Colonias , Preleucemia/diagnóstico , Enfermedad Aguda , Médula Ósea/fisiopatología , Dinoprostona , Femenino , Humanos , Cariotipificación , Leucemia/diagnóstico , Masculino , Persona de Mediana Edad , Preleucemia/patología , Preleucemia/fisiopatología , Prostaglandinas E/farmacología , Síndrome
3.
J Mol Endocrinol ; 34(2): 505-15, 2005 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-15821113

RESUMEN

The mRNA expression of two activin growth factor subunits (betaA- and betaC-activin), activin receptor subunits (ActRIIA, ActRIIB) and the activin-binding protein follistatin, and peptide expression of betaA-activin and betaC-activin subunits, were examined in regenerating rat liver after partial hepatectomy (PHx). Liver samples were collected from adult, male Sprague-Dawley rats, 12-240 h (n=3-5 rats per time point) after PHx or from sham-operated controls at the same time points. Hepatocyte mitosis and apoptosis were assessed histologically and by in situ cell death detection. RT and PCR were used to assess relative gene expression. betaA- and betaC-activin peptide immunoreactivity was assessed in liver and serum samples by western blotting, whereas cellular expression was investigated by immunohistochemistry, using specific monoclonal antibodies. betaA- and betaC-activin mRNA dropped to < 50% of sham control values 12 h after PHx and remained at this level until 168 h post-PHx, when betaA-activin expression increased to three times sham control values and betaC-activin mRNA returned to pre-PHx levels. A peak in follistatin expression was observed 24-48 h post-PHx, coincident with an increase in hepatocyte mitosis. No changes were observed in ActRIIA mRNA, whereas ActRIIB expression paralleled that of betaA-activin mRNA. betaC-activin immunoreactive homo- and heterodimers were observed in regenerating liver and serum. Mitotic hepatocytes frequently contained betaC-activin immunoreactivity, whereas apoptotic hepatocytes were often immunoreactive for betaA-activin. We conclude that betaA- and betaC-activin subunit proteins are autocrine growth regulators in regenerating liver and when expressed independently lead to hepatocyte apoptosis or mitosis in a subset of hepatocytes.


Asunto(s)
Receptores de Activinas/genética , Folistatina/metabolismo , Subunidades beta de Inhibinas/metabolismo , Regeneración Hepática/fisiología , Péptidos/metabolismo , Isoformas de Proteínas/metabolismo , Subunidades de Proteína/metabolismo , Receptores de Activinas/metabolismo , Animales , Apoptosis , Peso Corporal , Hepatocitos/citología , Hepatocitos/fisiología , Subunidades beta de Inhibinas/genética , Masculino , Mitosis , Péptidos/genética , Isoformas de Proteínas/genética , Subunidades de Proteína/genética , Distribución Aleatoria , Ratas , Ratas Sprague-Dawley , Factores de Tiempo
4.
J Bone Miner Res ; 13(1): 143-8, 1998 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-9443800

RESUMEN

In childhood, the most common site of fracture is the distal forearm. To determine whether young girls with these fractures have low bone density more commonly than fracture-free controls, we measured bone density at the radius, spine, hip, and whole body and total body bone mineral content, lean tissue mass, and fat mass by dual-energy X-ray absorptiometry in 100 Caucasian girls aged 3-15 years with recent distal forearm fractures and 100 age- and gender-matched controls. Bone density (age-adjusted ratios of all cases:controls with 95% confidence intervals) was lower in cases at the ultradistal radius 0.963 (0.930-0.996), 33% radius 0.972 (0.945-0.999), lumbar spine 0.945 (0.911-0.980), hip trochanter 0.952 (0.918-0.988), and total body 0.978 (0.961-0.995). Moreover, osteopenia (defined as Z score below -1), was more common in cases than controls (p < 0.05) in the forearm, spine, and hip, with one third of fracture cases having low spinal density. Odds ratios (95% confidence intervals) for low bone density were: ultradistal radius, 2.2 (1.1-4.6); lumbar spine, L2-L4, 2.6 (1.3-4.9); and femur trochanter, 2.0 (1.0-3.9). Fracture patients aged 8-10 years weighed more (mean +/- SD) than age-matched controls (37.2+/-8.0 kg vs. 32.5+/-6.6 kg, p < 0.01) while older patients reported lower current and past calcium intakes than matched controls (p < 0.05). We conclude that low bone density is more common throughout the skeleton in girls with forearm fractures than in those who have never broken a bone, supporting the view that low bone density may contribute to fracture risk in childhood.


Asunto(s)
Densidad Ósea , Fracturas del Radio/diagnóstico por imagen , Fracturas del Radio/fisiopatología , Fracturas del Cúbito/diagnóstico por imagen , Fracturas del Cúbito/fisiopatología , Adolescente , Niño , Preescolar , Femenino , Fémur/diagnóstico por imagen , Fémur/fisiología , Estado de Salud , Humanos , Pubertad , Radiografía , Radio (Anatomía)/diagnóstico por imagen , Radio (Anatomía)/fisiopatología
5.
Am J Clin Nutr ; 67(1): 44-9, 1998 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-9440374

RESUMEN

Receiver operating characteristic (ROC) curves were constructed to assess the value of body mass index (BMI) as a screening measure for total adiposity and to examine waist-to-hip ratio (WHR) and waist circumference as measures of central fat distribution. Body fat reference measurements were determined by dual-energy X-ray absorptiometry (DXA). The study population comprised 96 healthy white women aged 16-80 y. A positive reference test was defined as a result at or above the 75th percentile for our study population for all DXA measurements. Sensitivity and specificity were calculated at several percentile cutoffs for BMI, WHR, and waist girth. The areas under the ROC curves were calculated to compare the relative ability of each anthropometric technique to correctly classify subjects according to the reference measurement for that technique. BMI (our 75th percentile = 27.3) performed well as a screening measure of total adiposity, correctly identifying 83% of subjects with a high body fat mass while misclassifying only eight subjects [four false-negatives (subjects with high fat mass who were in the low BMI category) and four false-positives (subjects with a low fat mass who were in the high BMI category)]. The screening performance of WHR (our 75th percentile = 0.81) was lower, accurately categorizing 58% of subjects while misclassifying 28 subjects. By contrast, waist circumference (our 75th percentile = 86.9 cm) was significantly better than WHR at screening for regional fat distribution, accurately classifying 83% of subjects and misclassifying eight subjects (P < 0.05). We conclude that BMI and waist circumference provide simple yet sensitive methods for the estimation of total and central adiposity in groups of adult women.


Asunto(s)
Tejido Adiposo/patología , Constitución Corporal , Índice de Masa Corporal , Absorciometría de Fotón , Tejido Adiposo/diagnóstico por imagen , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Envejecimiento/fisiología , Femenino , Humanos , Persona de Mediana Edad , Curva ROC , Sensibilidad y Especificidad , Población Blanca
6.
Blood ; 62(1): 107-11, 1983 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-6407543

RESUMEN

As part of a larger study to determine the prognostic significance of cell marker phenotype in diffuse lymphomas, 51 patients with monoclonal B-cell lymphoma were further characterized by receptors for C3 (EAC rosettes) as well as heavy and light chain phenotypes. Patients with greater than 10% EAC rosette-forming cells were found to have a statistically significant longer survival than those with less than 10% EAC rosettes (p = 0.005). A similar trend in survival duration was found for patients whose cells expressed mu heavy chain on their surfaces when compared to those with gamma heavy chain on their cell surfaces (p = 0.05). No difference was observed for light chain phenotype. No correlation was observed between these prognostic groups and any of the three most frequently used histologic classifications (i.e., Rappaport, Lukes, Kiel).


Asunto(s)
Cadenas Pesadas de Inmunoglobulina/genética , Linfoma/diagnóstico , Receptores de Complemento/fisiología , Adulto , Anciano , Linfocitos B/inmunología , Femenino , Humanos , Inmunoglobulina G/análisis , Inmunoglobulina M/análisis , Linfoma/genética , Antígeno de Macrófago-1 , Masculino , Persona de Mediana Edad , Fenotipo , Pronóstico , Formación de Roseta
7.
Cancer Treat Rep ; 67(11): 981-6, 1983 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-6580071

RESUMEN

13-cis-Retinoic acid (13-cRA) induces maturation and differentiation of neoplastic myeloid cell lines in vitro. We conducted a phase I clinical trial of 13-cRA in patients with myelodysplastic syndromes (MDS), using a single daily oral dose schedule. Seventeen patients with MDS and one each with acute nonlymphoblastic leukemia and chronic myelogenous leukemia in blast crisis were treated with 13-cRA at doses ranging from 20 to 125 mg/m2/day. Hepatotoxicity was dose-limiting and was manifested by hyperbilirubinemia and increased SGOT levels. This effect was seen only at the highest dose level of 125 mg/m2/day and was completely reversible upon cessation of the drug. Other toxic effects were mild, and included cheilosis, hyperkeratosis, stomatitis, and elevation of serum triglyceride levels. Fifteen patients with MDS were evaluable for therapeutic response. Five patients showed improvement in hematologic parameters. These responses included normalization of bone marrow blast count and increases in leukocyte count, platelet count, and/or hemoglobin concentration. Responses were generally not seen until at least 3 weeks of therapy were completed. We conclude that further study of 13-cRA in myelodysplastic syndromes is warranted and recommend that future studies utilize a starting dose of 100 mg/m2.


Asunto(s)
Leucemia Mieloide/tratamiento farmacológico , Trastornos Mieloproliferativos/tratamiento farmacológico , Preleucemia/tratamiento farmacológico , Tretinoina/administración & dosificación , Administración Oral , Adulto , Anciano , Recuento de Células Sanguíneas , Relación Dosis-Respuesta a Droga , Evaluación de Medicamentos , Femenino , Humanos , Isotretinoína , Hígado/efectos de los fármacos , Masculino , Persona de Mediana Edad , Trastornos Mieloproliferativos/sangre , Preleucemia/sangre , Tretinoina/efectos adversos
SELECCIÓN DE REFERENCIAS
Detalles de la búsqueda