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1.
Transpl Int ; 8(5): 346-52, 1995.
Artigo em Inglês | MEDLINE | ID: mdl-7576015

RESUMO

Histology of liver allografts is the gold standard for diagnosis of acute cellular rejection. However, scoring the severity of rejection and distinguishing it from other infiltrations is not easy. Only one group has evaluated biopsies morphometrically and also suggested that eosinophils are a specific diagnostic feature. We quantitated eosinophil count in 92 biopsies in a group of 25 patients and, in another group of 30 patients, used morphometric image analysis to measure the cross-sectional area and cell density in each portal tract in day 5 protocol liver biopsies. Rejection was diagnosed by pathological evaluation confirmed with clinical and biochemical graft dysfunction graded histologically into mild or moderate-to-severe. The control groups were five patients with no rejection, nine patients with CMV infection, and eight biopsies in eight patients for whom the cause of the liver dysfunction was obscure. The cross-sectional area, the inflammatory cell count of each portal tract and the mean portal tract inflammatory cell density (cells/mm2) increased with the severity of rejection. In each case the regression coefficient was statistically significant. Correlating the mean of the total inflammatory cell count with the mean of the portal inflammatory cell density (cell/mm2) gave far better separation of the mild rejection and moderate-to-severe rejection groups. Eosinophils were specific for the presence of acute cellular rejection and increased with the severity of rejection. They were absent in the no rejection group, in the CMV group and in those with obscure liver dysfunction. The eosinophil count fell markedly following treatment of rejection.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Eosinófilos , Transplante de Fígado , Fígado/patologia , Rejeição de Enxerto , Humanos , Contagem de Leucócitos , Estudos Retrospectivos , Transplante Homólogo
2.
Med Hypotheses ; 40(3): 165-8, 1993 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-8502195

RESUMO

Localized Hodgkin's disease (HD) is curable in the great majority of patients. However, common programs of chemotherapy for this disease render most men permanently azoospermic. In studies of seminal cryopreservation prior to treatment, it has been recognized that many men with HD are dyspermic at diagnosis. It is hypothesized that this abnormality reflects a change in the cellular regulation of spermatogenesis; specifically an alteration in the balance between distinct sub-populations of lymphocytes which normally either inhibit or stimulate the production of sperm. This change in regulation within the testes is believed to be part of a systemic perturbation which is unrelated to the extent of HD but is potentially reversible with effective treatment of the primary disease. Recognizing the distinction between sperm analyses and fertility status, it is proposed that radiotherapy of localized HD, delivered in a manner that is not toxic to the male gonad, will restore useful spermatogenesis in patients who are dyspermic (and probably subfertile) before treatment is initiated.


Assuntos
Doença de Hodgkin/imunologia , Oligospermia/imunologia , Linfócitos T/imunologia , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Fertilidade , Doença de Hodgkin/complicações , Doença de Hodgkin/tratamento farmacológico , Doença de Hodgkin/fisiopatologia , Humanos , Imunidade Celular , Linfonodos/imunologia , Masculino , Oligospermia/etiologia , Oligospermia/fisiopatologia
3.
Dig Dis Sci ; 37(5): 751-6, 1992 May.
Artigo em Inglês | MEDLINE | ID: mdl-1563319

RESUMO

The effects of 48 days of streptozotocin-induced diabetes mellitus in rats on plasma concentrations of gastrin, somatostatin, pancreatic glucagon, and enteroglucagon have been assessed. In addition, neuroendocrine changes in sections of gastric mucosa were quantified using a computer-assisted morphometric system following immunohistochemical staining with polyclonal antibodies directed against gastrin, PGP 9.5 (a neural protein), and somatostatin. Diabetes resulted in significantly increased fasting plasma concentrations of somatostatin, and entero- and pancreatic glucagon. In contrast, lower plasma gastrin concentrations and decreased antral G-cell density were noted in diabetic rats. Gastric somatostatin and neuronal PGP 9.5 stain densities were unaltered by diabetes. Stomachs of diabetic rats weighed less, but both the jejunum and ileum showed evidence of mucosal hyperplasia. The gastric neuroendocrine atrophy observed in diabetes may be a consequence of elevated plasma somatostatin derived from nongastric sources. The enhanced growth of the intestinal mucosa may be related, directly or indirectly, to raised intraluminal glucose concentration in diabetes.


Assuntos
Diabetes Mellitus Experimental/fisiopatologia , Mucosa Gástrica/metabolismo , Sistemas Neurossecretores/fisiologia , Animais , Glicemia/análise , Diabetes Mellitus Experimental/sangue , Jejum/sangue , Mucosa Gástrica/patologia , Hormônios Gastrointestinais/sangue , Hormônios Gastrointestinais/metabolismo , Imuno-Histoquímica , Intestino Delgado/patologia , Masculino , Sistemas Neurossecretores/patologia , Ratos , Ratos Endogâmicos
4.
J Clin Endocrinol Metab ; 74(5): 1068-74, 1992 May.
Artigo em Inglês | MEDLINE | ID: mdl-1569154

RESUMO

Environmental lighting, which regulates seasonal breeding in many animal species, has not been examined as a regulator of reproduction or puberty in man or nonhuman primates. In this study we examined the effects of controlled alternating long and short daily photoperiods, independent of other environmental variables, on testicular size and function in rhesus monkeys. Sixteen animals, some pubertal, others prepubertal, were individually caged indoors in light-controlled rooms. They were subjected to a 32-week "year" with alternating 16-week cycles of long (16 h of light and 8 h of darkness) or short (8 h of light and 16 h of darkness) days. Animals were examined every 2 weeks over four 32-week "years". Body weight, testicular diameter, and testicular volume were measured, and blood was collected for testosterone and PRL determinations. We found that although short days did not trigger testicular development in prepubertal animals, testicular growth was markedly enhanced by short days in postpubertal animals, accompanied by increased plasma testosterone levels and reduced PRL levels. In long days, testes regressed, testosterone levels fell, and PRL levels rose. The periodicity of testicular size, as determined by spectral analysis, showed a strong signal at a cycle length of 31 +/- 13 weeks, but no signal at intervals close to the natural 52-week year, indicating that the observed periodicity is induced by the changes in lighting, rather than by circannual changes in other variables. These studies establish that changes in photo-period alone can modulate reproductive function in a higher primate and suggest that the onset of puberty is not directly driven by seasonal fluctuations in day length.


Assuntos
Luz , Macaca mulatta/fisiologia , Reprodução , Animais , Peso Corporal , Masculino , Prolactina/sangue , Maturidade Sexual , Testículo/anatomia & histologia , Testosterona/sangue
5.
J Clin Endocrinol Metab ; 72(1): 39-45, 1991 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-1986026

RESUMO

Growth retardation as well as the development of Cushingoid features in adrenally insufficient patients treated with the currently accepted replacement dose of cortisol (33-41 mumol/day.m2; 12-15 mg/m2.day) prompted us to reevaluate the cortisol production rate (FPR) in normal subjects and patients with Cushing's syndrome, using a recently developed thermospray liquid chromatography-mass spectrometry method. The stable isotope [9,12,12-2H3]cortisol was infused continuously for 31 h at about 5% of the anticipated FPR. Blood samples were obtained at 20-min intervals for 24 h, spun, and pooled in 4-h groups. Tracer dilution in plasma was determined by liquid chromatography/mass spectrometry. The method was validated with controlled infusions in 6 patients with adrenal insufficiency. Results from 12 normal volunteers revealed a FPR of 27.3 +/- 7.5 mumol/day (9.9 +/- 2.7 mg/day) or 15.7 mumol/day.m2; 5.7 mg/m2. day). A previously unreported circadian variation in FPR was observed. Patients with Cushing's syndrome demonstrated unequivocal elevation of FPR and cortisol concentration correlated during each sample period in normal volunteers, indicating that cortisol secretion, rather than metabolism, is mainly responsible for changes in plasma cortisol. Our data suggest that the FPR in normal subjects may be lower than previously believed.


Assuntos
Síndrome de Cushing/metabolismo , Hidrocortisona/biossíntese , Cromatografia Líquida , Ritmo Circadiano , Deutério , Humanos , Hidrocortisona/sangue , Hidrocortisona/metabolismo , Técnicas de Diluição do Indicador , Cinética , Espectrometria de Massas , Valores de Referência
7.
J Gen Virol ; 68 ( Pt 7): 1835-48, 1987 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-3037008

RESUMO

The genome of the prototype stain of coxsackievirus B4 (J.V.B. Benschoten) has been cloned in Escherichia coli and its complete nucleotide sequence determined. Excluding the poly(A) tract, the RNA genome is 7395 nucleotides in length and appears to encode a single polyprotein of 2183 amino acids. The predicted amino acid sequence of the polyprotein shows close homology (88%) to that of the previously sequenced coxsackievirus B3 and to certain regions of the polyproteins of the polioviruses and human rhinovirus 14. This allows identification of putative polyprotein cleavage signals, antigenic domains and other structural features likely to be important to the biological integrity of the virus.


Assuntos
Enterovirus Humano B/genética , Genes Virais , RNA Viral/genética , Sequência de Aminoácidos , Sequência de Bases , Genes , Picornaviridae/genética , Precursores de Proteínas/genética , Processamento de Proteína Pós-Traducional , Homologia de Sequência do Ácido Nucleico , Especificidade da Espécie , Proteínas Virais/biossíntese , Proteínas Virais/genética
8.
J Clin Endocrinol Metab ; 64(6): 1194-8, 1987 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-3106397

RESUMO

Recent studies in acutely castrated males of several species have demonstrated that testosterone (T) alone, given in doses that produce normal plasma T levels, can maintain normal plasma FSH and LH levels. This suggests that a nonsteroidal factor from the seminiferous tubule is not required to regulate FSH release, and raises the possibility that Leydig cell function may not be fully normal in oligo- or azoospermic men with increased plasma FSH levels. To clarify this, we studied T production rates in 11 sexually mature, infertile, but otherwise healthy men who had increased plasma FSH and normal plasma LH, T, and estradiol levels and in 9 normal men. Although individual plasma T and LH levels in the infertile men were within the normal ranges, the mean plasma T level of the infertile men was significantly lower (P less than 0.002), and the mean plasma LH level was significantly higher (P less than 0.002) than values in the normal men. The infertile men also had significantly lower plasma free T concentrations (P less than 0.005), while sex hormone-binding globulin and estradiol levels were similar to those of the normal men. The production rate of T in the infertile men was half that in the normal men (P less than 0.001). We conclude that T production is significantly reduced in infertile men who have a selective increase in plasma FSH. Because of the known role of Leydig cell sex steroids in the negative feedback control of FSH, this finding may explain the elevated plasma FSH concentrations characteristic of men with germ cell loss without the need to postulate a deficiency of a separate seminiferous tubule factor.


Assuntos
Hormônio Foliculoestimulante/sangue , Infertilidade Masculina/fisiopatologia , Células Intersticiais do Testículo/fisiologia , Adolescente , Adulto , Estradiol/sangue , Humanos , Infertilidade Masculina/sangue , Infertilidade Masculina/patologia , Hormônio Luteinizante/sangue , Masculino , Valores de Referência , Testosterona/sangue
9.
J Clin Invest ; 75(6): 1781-5, 1985 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-2989331

RESUMO

The continuous 24-h infusion of a maximally stimulating dose (1 micrograms/kg per h) of ovine corticotropin-releasing factor (CRF) in man caused a modest elevation of plasma cortisol (17.2 +/- 1.4 micrograms/dl) and urinary-free cortisol (173 +/- 43 micrograms/24 h) concentrations, which was far less than that seen with a maximally stimulating dose of ACTH (50.4 +/- 2.2 micrograms/dl and 1,200 +/- 94 micrograms/24 h, respectively). The circadian rhythms of plasma ACTH and cortisol were preserved during CRF administration. An intravenous bolus injection of 1 microgram/kg of ovine CRF given to normal volunteers under basal conditions resulted in elevated plasma ACTH and cortisol peak levels (28 +/- 6 pg/ml and 15.0 +/- 1.0 micrograms/dl, respectively). However, no plasma ACTH and cortisol responses were observed when an identical CRF stimulation test was given at the end of the continuous infusion. These findings suggest that the stimulatory activity of exogenous CRF on the ACTH-secreting cells of the pituitary gland is restrained by the negative feedback of cortisol. The persistent circadian rhythm of ACTH, despite a constant level of plasma CRF during the infusion, suggests that the circadian variation in the activity of the hypothalamic-pituitary-adrenal axis cannot be explained solely by circadian periodicity of the endogenous CRF stimulus.


Assuntos
Hormônio Liberador da Corticotropina/farmacologia , Hidrocortisona/metabolismo , Glândulas Suprarrenais/fisiologia , Hormônio Adrenocorticotrópico/sangue , Hormônio Adrenocorticotrópico/farmacologia , Adulto , Animais , Ritmo Circadiano/efeitos dos fármacos , Síndrome de Cushing/fisiopatologia , Feminino , Hormônios/farmacologia , Humanos , Hidrocortisona/urina , Sistema Hipotálamo-Hipofisário/fisiologia , Masculino , Pessoa de Meia-Idade , Taxa Secretória/efeitos dos fármacos , Ovinos
10.
Horm Metab Res ; 17(2): 110-1, 1985 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-3988237

RESUMO

The male infant rhesus monkey (Macaca mulatta) undergoes a period of testicular activation similar to that seen in the human infant. Plasma testosterone (T) concentrations rise after birth, reaching levels of about 500 ng/dl at 1-3 mo of age and then fall to approximately 50 ng/dl at 60 mo. The plasma T metabolic clearance rates (MCRT) and production rates (PRT) were measured in two rhesus infants at 1 and 6 mo of age to determine the mechanism of the observed increase in plasma T. While there was little change in the MCRT between 1 and 6 mo, PRT was much higher at 1 mo than at 60 mo of age. These observations are consistent with the hypothesis that the increased plasma testosterone levels in infant rhesus monkeys reflect an increased production of testosterone rather than an altered metabolic disposition of the hormone.


Assuntos
Macaca mulatta/sangue , Macaca/sangue , Testosterona/sangue , Fatores Etários , Animais , Masculino , Taxa de Depuração Metabólica
11.
J Clin Endocrinol Metab ; 58(1): 192-6, 1984 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-6605972

RESUMO

Corticotropin-releasing factor (CRF), a 41-amino acid peptide isolated and sequenced from ovine hypothalami, has potential clinical application as a provocative test of the hypothalamic-pituitary-adrenal axis. To define its pharmacokinetic parameters in man, we measured the MCR and plasma half-life of immunoreactive CRF (IR-CRF) by the pulse injection and continuous infusion methods. Synthetic ovine CRF was given to 12 normal men as a bolus injection (1 microgram/kg; n = 6) or as a continuous infusion (0.51 +/- 0.05 micrograms/kg X h; n = 6) over 8 h. The disappearance curve of IR-CRF from plasma was biexponential. The plasma half-life of IR-CRF was 11.6 +/- 1.5 min (mean +/- SE) for the fast component and 73 +/- 8 min for the slow component. The MCR using the pulse injection technique was 95 +/- 11 liters/m2 X day, and the volume of distribution was 6.2 +/- 0.5 liters. Continuous infusion of CRF gave approximately the same MCR (88 +/- 7 liters/m2 X day). A small percentage of IR-CRF (approximately 0.03%) was found in the urine at the end of the continuous infusion. The relatively low MCR of CRF may explain its prolonged biological action in primates and man.


Assuntos
Hormônio Liberador da Corticotropina/metabolismo , Adulto , Cromatografia em Gel , Hormônio Liberador da Corticotropina/sangue , Meia-Vida , Humanos , Infusões Parenterais , Injeções Intravenosas , Cinética , Masculino , Taxa de Depuração Metabólica , Radioimunoensaio
12.
J Endocrinol Invest ; 6(6): 473-8, 1983 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-6672071

RESUMO

A 31 year old Chinese man was found to have a large basal encephalocele extending into the nasopharynx associated with a cleft palate and chiasmal damage producing visual field defects. He was found to have marked hypothalamic-pituitary dysfunction including deficiencies of growth hormone, thyrotropin, adrenocorticotropic hormone and gonadotropins, diabetes insipidus, adipsia with essential hypernatremia and poikilothermia. This man illustrates the importance of careful assessment of patients with craniofacial anomalies and outlines a simple investigational protocol.


Assuntos
Encefalocele/fisiopatologia , Sistema Hipotálamo-Hipofisário/fisiopatologia , Adulto , Glicemia/metabolismo , Regulação da Temperatura Corporal , Humanos , Masculino
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