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1.
Bioprocess Biosyst Eng ; 40(7): 989-1006, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28391378

RESUMO

A strategy for monitoring fermentation processes, specifically, simultaneous saccharification and fermentation (SSF) of corn mash, was developed. The strategy covered the development and use of first principles, semimechanistic and unstructured process model based on major kinetic phenomena, along with mass and energy balances. The model was then used as a reference model within an identification procedure capable of running on-line. The on-line identification procedure consists on updating the reference model through the estimation of corrective parameters for certain reaction rates using the most recent process measurements. The strategy makes use of standard laboratory measurements for sugars quantification and in situ temperature and liquid level data. The model, along with the on-line identification procedure, has been tested against real industrial data and have been able to accurately predict the main variables of operational interest, i.e., state variables and its dynamics, and key process indicators. The results demonstrate that the strategy is capable of monitoring, in real time, this complex industrial biomass fermentation. This new tool provides a great support for decision-making and opens a new range of opportunities for industrial optimization.


Assuntos
Fermentação , Biomassa , Carboidratos , Etanol , Saccharomyces cerevisiae , Zea mays
2.
Kyobu Geka ; 61(3): 238-41, 2008 Mar.
Artigo em Japonês | MEDLINE | ID: mdl-18323192

RESUMO

A 74-year-old man had pustulant bilateral arthritis complicated with sepsis and disseminated intravascular coagulation (DIC). Microbiologic study of blood sample showed Streptococcus and methicillin resistant Staphylococcus aureus (MRSA). He was complicated with postulant diskitis since then. Medical treatment for DIC and administration of antibiotics were performed. Preoperative echocardiography revealed massive aortic regurgitation and vegetation of aortic valve, moderate pulmonary regurgitation and vegetation of pulmonary valve, massive mitral regurgitation, massive tricuspid regurgitation. He was diagnosed as infective quadruple valve endocarditis. He received aortic valve replacement, pulmonary valve replacement, mitral valve repair and tricuspid valve repair. Postoperative echocardiography showed satisfactory function of bioprosthesis. Postoperative course was uneventful.


Assuntos
Endocardite/cirurgia , Doenças das Valvas Cardíacas/cirurgia , Valvas Cardíacas/cirurgia , Idoso , Endocardite/microbiologia , Doenças das Valvas Cardíacas/microbiologia , Implante de Prótese de Valva Cardíaca , Humanos , Masculino , Resistência a Meticilina , Índice de Gravidade de Doença , Infecções Estafilocócicas , Infecções Estreptocócicas , Resultado do Tratamento
3.
J Clin Invest ; 62(6): 1395-8, 1978 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-219030

RESUMO

To elucidate whether or not beta-endorphin exists in plasma of normal subjects, plasma extracts obtained before and after metyrapone administration were subjected to gel exclusion chromatography, and fractions obtained were assayed by a sensitive radioimmunoassay for beta-endorphin. The basal plasma level of beta-endorphin was 5.8 +/- 1.1 pg/ml (mean +/- SE, n = 5), which rose significantly to the level of 48.9 +/- 3.8 pg/ml after a single oral dose (30 mg/kg of body wt) of metyrapone administration (P less than 0.001). Plasma ACTH levels also increased from the mean basal level of 73 +/- 4 pg/ml to 269 +/- 41 pg/ml after metyrapone administration. These results indicate that beta-endorphin, distinct from beta-lipotropin, exists in normal human plasma and that it is released from the pituitary concomitantly with ACTH.


Assuntos
Endorfinas/sangue , Metirapona/farmacologia , Hormônio Adrenocorticotrópico/sangue , Hormônio Adrenocorticotrópico/metabolismo , Adulto , Endorfinas/metabolismo , Humanos , Masculino , Hipófise/efeitos dos fármacos , Hipófise/metabolismo , Radioimunoensaio , Fatores de Tempo , beta-Lipotropina/sangue
4.
J Clin Invest ; 66(6): 1383-90, 1980 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-6255011

RESUMO

To elucidate the significance of beta-endorphin in human cerebrospinal fluid (CSF), CSF levels of beta-endorphin-like immunoreactivity (beta-EP-LI) in various diseases were determined by a specific radioimmunoassay and compared with simultaneously determined ACTH-like immunoreactivity (ACTH-LI) levels in CSF. CSF beta-EP-LI and ACTH-LI in the control group, consisting of 5 normal subjects and 19 patients with nonendocrine diseases, were 22.2+/-1.3 and 14.6+/-0.4 fmol/ml, respectively. CSF levels of these peptides in patients with schizophrenia (n = 19) and acromegaly (n = 10) were not significantly different from those in the control group. Patients with Cushing's disease (n = 7) had significantly lower CSF beta-EP-LI and ACTH-LI levels than those in the control group. Four of them showed a parallel increase in CSF beta-EP-LI and CSF ACTH-LI levels after the complete removal of pituitary microadenomas (P < 0.05). Gel chromatography of CSF beta-EP-LI from a normal volunteer, a control patient, and one patient each with catatonia, Nelson's syndrome, Cushing's syndrome (adrenal adenoma), and acromegaly gave similar patterns consisting of three peaks with the elution positions comparable to those of authentic beta-endorphin, beta-lipotropin, and possibly their precursor molecule. Gel chromatographic patterns of CSF beta-EP-LI and ACTH-LI were compared in a normal volunteer. The first peaks of beta-EP-LI and ACTH-LI eluted at the same position and the second peak of ACTH-LI coincided with the elution position of authentic ACTH.CSF beta-EP-LI and ACTH-LI levels determined every 5 min over a period of 80 min in three normal volunteers did not show moment-to-moment variability.A significant correlation (r = 0.75, P < 0.001) was seen between CSF beta-EP-LI and ACTH-LI levels in normal subjects and patients studied (n = 73). This suggests that beta-endorphin and ACTH in human CSF share the common regulatory mechanism in normal and pathologic conditions.


Assuntos
Hormônio Adrenocorticotrópico/líquido cefalorraquidiano , Endorfinas/líquido cefalorraquidiano , Acromegalia/líquido cefalorraquidiano , Adulto , Síndrome de Cushing/líquido cefalorraquidiano , Feminino , Glucocorticoides/farmacologia , Humanos , Masculino , Pessoa de Meia-Idade , Radioimunoensaio , Esquizofrenia/líquido cefalorraquidiano
5.
Kyobu Geka ; 59(4): 319-23, 2006 Apr.
Artigo em Japonês | MEDLINE | ID: mdl-16613151

RESUMO

This study was aimed at determining the tolerable lower limit of the indexed effective orifice area (EOAI) to prevent patient-prosthesis mismatch (PPM). Echocardiography was performed in 87 consecutive patients who underwent aortic valve replacement (AVR). EOAI was estimated for each type and size of prosthesis and used to define PPM as moderate if >0.65 cm2/ m2 and < or = 0.85 cm2/m2, and severe if < or = 0.65 cm/m2. Aortic valve pressure gradients, left ventricular dimensions, and outcome (in-hospital and 1-year) were analyzed in the presence or absence of abnormal gradients (> or = 40 mmHg) to assess the influence of a small valve (19 mm or less labeled size). Severe PPM was found in 23% of all patients, and 50% of the severe PPM patients had an abnormal gradient. There was 1 death and 1 brain damage from ventricular fibrillation because of severe PPM in the abnormal gradient group with a small valve. In PPM patients with a small valve, EOAI (0.61 +/- 0.04 vs 0.69 +/- 0.07) and preoperative interventricular septal thickness (IVST : 16.4 +/- 2.6 mm vs 13.5 +/- 1.5 mm) were significantly different between abnormal and normal gradient groups. An EOAI > or = 0.69 appeared to be tolerable in patients with a lower level of hypertrophy (IVST < 16 mm).


Assuntos
Estenose da Valva Aórtica/cirurgia , Valva Aórtica/cirurgia , Implante de Prótese de Valva Cardíaca , Próteses Valvulares Cardíacas , Idoso , Estenose da Valva Aórtica/diagnóstico por imagem , Ecocardiografia , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Desenho de Prótese , Ajuste de Prótese
6.
Endocrinology ; 111(2): 418-24, 1982 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-6284479

RESUMO

gamma MSH, a putative hormone in the N-terminal region of the ACTH/beta-endorphin (beta-EP) precursor protein, was studied by RIA with an antiserum against gamma 3MSH in ACTH-producing mouse pituitary tumor cells, AtT-20/D16v. Serial dilution of the culture medium or the cell extract gave parallel lines to the standard curve in the RIA for gamma MSH. Rat median eminence extracts enhanced the release of gamma MSH-like immunoreactivity (gamma MSH-LI) concomitant with ACTH-like immunoreactivity (ACTH-LI) and beta-EP-like immunoreactivity (beta-EP-LI). Dexamethasone suppressed the release of gamma MSH-LI as well as ACTH-LI and beta-EP-LI. Gel exclusion chromatography of the culture medium and the cell extract has revealed that gamma MSH-LI consists of two peaks; one eluted near the elution position of beta-lipotropin and the other near the elution position of beta-EP. There was no peak corresponding to the elution position of synthetic gamma 3MSH. However, sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) has demonstrated that gamma MSH-LI migrated at five positions with molecular weights of 31K, 21-23K, 16-17K, 13-14K, and 3.8K, respectively. The 31K gamma MSH coincided with the migration position of 31K ACTH of 31K beta-EP, and 21-23K gamma MSH coincided with the position of 21-23K ACTH on SDS-PAGE. The 16-17K gamma MSH coincided with the mouse 16K fragment (reported by Eipper and Mains) of ACTH-beta-lipotropin precursor protein in the migration in SDS-PAGE and in immunoreactivity to anti-gamma MSH antiserum. [3H]Glucosamine was incorporated into 16K, 13K, and 3.8K gamma MSH. These results suggest that AtT-20/D16v cells produce gamma MSH-LIs with molecular weights of 31K, 21-23K, 16-17K, 13-14K, and 3.8K, and they are secreted concomitantly with ACTH-LI and beta-EP-LI.


Assuntos
Hormônio Adrenocorticotrópico/metabolismo , Hormônios Estimuladores de Melanócitos/metabolismo , Neoplasias Hipofisárias/metabolismo , Animais , Linhagem Celular , Cromatografia em Gel , Dexametasona/farmacologia , Eletroforese em Gel de Poliacrilamida , Endorfinas/metabolismo , Glucosamina/metabolismo , Eminência Mediana/análise , Camundongos , Neoplasias Hipofisárias/análise , Coelhos , Extratos de Tecidos/farmacologia , beta-Endorfina
7.
J Clin Endocrinol Metab ; 50(1): 194-7, 1980 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-6243130

RESUMO

To elucidate the regulation of secretion of beta-endorphin in Nelson's syndrome, both ACTH and beta-endorphin were measured using RIA. We found that beta-endorphin and ACTH were secreted concomitantly in responses to the administration of lysine-8-vasopressin and TRH. Conversely, the administration of somatostatin to this patient reduced the secretion of both beta-endorphin and ACTH. Thus, beta-endorphin is probably secreted cooredinately with ACTH in patients with Nelson's syndrome.


Assuntos
Endorfinas/sangue , Lipressina , Síndrome de Nelson/sangue , Neoplasias Hipofisárias/sangue , Somatostatina , Hormônio Liberador de Tireotropina , Hormônio Adrenocorticotrópico/sangue , Adulto , Feminino , Humanos , Técnicas In Vitro , Cinética
8.
J Clin Endocrinol Metab ; 51(5): 1205-7, 1980 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-6252236

RESUMO

Using a specific radioimmunoassay for gamma-melanotropin (gamma-MSH), one of the predicted fragments in the amino-terminal portion of the adrenocorticotropin(ACTH)-beta-lipotropin (beta-LPH) precursor, gamma-MSH-like immunoreactivity (gamma-MSH-LI) was detected in human plasma from 4 of 5 patients with Addison's disease and 2 of 3 patients with Nelson's syndrome. None of the normal subjects or patients with Cushing's disease showed detectable concentrations (more than 150 pg/ml) of gamma-MSH-LI. gamma-MSH-LI was secreted concomitantly with ACTH-like immunoreactivity (ACTH-LI) and beta-endorphin-like immunoreactivity (beta-endorphin-LI) in response to insulin-induced hypoglycemia and the administration of lysine-vasopressin. Conversely, intravenous injection of cortisol lowered plasma concentrations of gamma-MSH-LI concomitantly with those of ACTH-LI and beta-endorphin-LI. Gel chromatographic studies of the plasma extracts showed a single peak of gamma-MSH-LI near the elution position of human beta-LPH. These results suggest that gamma-MSH-LI in human plasma is present as a big form and that this big gamma-MSH is secreted concomitantly with ACTH and beta-endorphin.


Assuntos
Hormônio Adrenocorticotrópico/metabolismo , Endorfinas/metabolismo , Hormônios Estimuladores de Melanócitos/metabolismo , Doença de Addison/sangue , Síndrome de Cushing/sangue , Humanos , Hidrocortisona , Insulina , Lipressina , Síndrome de Nelson/sangue , Valores de Referência
9.
J Clin Endocrinol Metab ; 49(6): 838-41, 1979 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-229118

RESUMO

To elucidate whether insulin-induced hypoglycemia enhances the release of beta-endorphin in man, plasma extracts obtained from healthy subjects and patients with Graves' disease before and 45 min after insulin injection were subjected to gel chromatography, and the fractions obtained were measured by RIA for beta-endorphin. In four healthy subjects, basal plasma beta-endorphin levels were less than 3 to 3.1 pg/ml, and the levels rose substantially to 47.5 +/- 12.4 pg/ml (mean +/- SE) 45 min after insulin injection. Basal plasma beta-endorphin levels in three hyperthyroid patinets (less than 3 to 3.8 pg/ml) did not seem to be different from those in healthy subjects; however, the rise after insulin injection tended to be higher in cases of hyperthyroidism, with a peak value of 68.5 +/- 9.7 pg/ml. Plasma beta-lipotropin and ACTH levels also rose in parallel with beta-endorphin in response to insulin-induced hypoglycemia in both healthy subjects and hyperthyroid patients. It would thus appear that beta-endorphin, like ACTH or beta-lipotropin, is released in human subjects by hypoglycemic stress.


Assuntos
Endorfinas/sangue , Doença de Graves/sangue , Insulina , Hormônio Adrenocorticotrópico/sangue , Adulto , Feminino , Humanos , Hipoglicemia/induzido quimicamente , Masculino , Pessoa de Meia-Idade , beta-Lipotropina/sangue
10.
J Clin Endocrinol Metab ; 50(6): 1147-8, 1980 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-6246146

RESUMO

Using a specific radioimmunoassay for gamma-MSH, a predicted peptide in the cryptic N-terminal portion of the adrenocorticotropin-beta-lipotropin precursor, gamma-MSH-like immunoreactivity (gamma-MLI) was detected in two ectopic ACTH producing tumors. Gel chromatographic studies on Bio-Gel P-60 revealed one or two peaks of gamma-MLI; one was eluted near th elution position of beta-LPH, compatible with gamma-MLI in human pituitary and the other emerged near the position of beta-endorphin. These results indicate that ectopic ACTH-producing tumors eleborate not only ACTH, beta-endorphin but also gamma-MLI.


Assuntos
Hormônio Adrenocorticotrópico/metabolismo , Hormônios Estimuladores de Melanócitos/análise , Neoplasias da Glândula Tireoide/análise , Hormônio Adrenocorticotrópico/análise , Endorfinas/análise , Humanos , Radioimunoensaio , Neoplasias da Glândula Tireoide/metabolismo , beta-Lipotropina/análise
11.
J Clin Endocrinol Metab ; 53(1): 213-14, 1981 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-6113249

RESUMO

Using a highly specific and sensitive radioimmunoassay for dynorphin(1-13), dynorphin-like immunoreactivity (dynorphin-LI) was detected in two extramedullary pheochromocytomas and a medullary pheochromocytoma. The contents of dynorphin-LI of two extramedullary and a medullary tumors were 9.2, 2.2, and 34.0 pmole/g, respectively. Gel chromatographic studies of tumor extracts on Sephadex G-50 revealed a peak of dynorphin-LI eluting at the same position as dynorphin-LI contaminated in porcine ACTH extract (Sigma) and another portion of dynorphin-LI eluting in a range of molecular weights larger than that of dynorphin-LI in porcine ACTH extract. These results indicate the presence of dynorphin and possibly its precursor peptide(s) in pheochromocytoma.


Assuntos
Neoplasias das Glândulas Suprarrenais/metabolismo , Endorfinas/metabolismo , Feocromocitoma/metabolismo , Medula Suprarrenal , Hormônio Adrenocorticotrópico , Cromatografia em Gel , Dinorfinas , Humanos , Peso Molecular
12.
J Clin Endocrinol Metab ; 56(5): 1080-3, 1983 May.
Artigo em Inglês | MEDLINE | ID: mdl-6300175

RESUMO

gamma 1 MSH-like immunoreactivity in bovine pituitary glands, hypothalami, human pituitary glands, ectopic ACTH-producing tumors, and human gastric antral mucosa was investigated using a newly developed RIA for gamma 1 MSH. The minimum detectable quantity of gamma 1 MSH was 3 pg/tube, and the antibody did not cross-react with gamma 2 MSH, gamma 3 MSH, alpha MSH, beta MSH, ACTH, beta-lipotropin, or beta-endorphin. Bovine anterior pituitary, intermediate-posterior pituitary, and hypothalamus contained more than two molecular weight forms of gamma 1 MSH-like immunoreactivities. On the other hand, gamma 1 MSH-like immunoreactivity was not detected in human pituitary glands or human gastric antral mucosa, but was detected in one of seven ectopic ACTH-producing tumors. These results suggest a limited processing of the ACTH-beta-lipotropin precursor to gamma 1 MSH in human tissues, although a rapid degradation of gamma 1 MSH could not be ruled out completely.


Assuntos
Hormônio Adrenocorticotrópico/biossíntese , Mucosa Gástrica/análise , Hipotálamo/análise , Hormônios Estimuladores de Melanócitos/análise , Neoplasias/análise , Hipófise/análise , Animais , Carcinoma/análise , Bovinos , Cromatografia em Gel , Humanos , Hormônios Estimuladores de Melanócitos/imunologia , Neoplasias/metabolismo , Hormônios Adeno-Hipofisários/análise , Hormônios Adeno-Hipofisários/imunologia , Pró-Opiomelanocortina , Precursores de Proteínas/análise , Precursores de Proteínas/imunologia , Radioimunoensaio , Neoplasias da Glândula Tireoide/análise
13.
J Clin Endocrinol Metab ; 54(2): 392-6, 1982 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-6274902

RESUMO

gamma MSH-like, ACTH-like, and beta-endorphin-like immunoreactivities (gamma MSH-LI, ACTH-LI, and beta-endorphin-LI, respectively) were detected in water extracts of four human gastric antral mucosa. The concentrations of gamma MSH-LI, ACTH-LI, and beta-endorphin-LI in the boiling water extracts were 9.9 +/- 3.3, 6.2 +/- 1.8, and 3.9 +/- 1.3 ng/g (mean +/- SE), respectively. Gel exclusion chromatography on a Bio-Gel P-60 column showed that most ACTH-LI and beta-endorphin-LI were eluted at the elution positions of human ACTH and beta-endorphin, respectively. The major peak of gamma MSH-LI was eluted at the elution position of big gamma MSH-LI, but another peak was eluted at the elution position of small gamma MSH-LI, as in bovine intermediate pituitary. Concanavalin A-agarose affinity chromatography showed that 52% of gamma MSH-LI was specifically bound to the column, but only 8% of ACTH-LI and none of beta-endorphin-LI were specifically bound. These results suggest that there exists an ACTH/beta-lipotropin common precursor protein in human antral mucosa and that the processing of the precursor is accelerated as a bovine intermediate pituitary, indicating possible roles of these peptides in the function of the gastrointestinal tract.


Assuntos
Hormônio Adrenocorticotrópico/metabolismo , Endorfinas/metabolismo , Mucosa Gástrica/metabolismo , Hormônios Estimuladores de Melanócitos/metabolismo , Antro Pilórico/metabolismo , Cromatografia de Afinidade , Cromatografia em Gel , Humanos , Masculino , beta-Endorfina
14.
J Clin Endocrinol Metab ; 50(2): 230-3, 1980 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-7354109

RESUMO

To elucidate the nature of beta-endorphin-like immunoreactivity in human cerebrospinal fluid (CSF) and its relationship with plasma beta-endorphin, plasma and CSF specimens were obtained simultaneously. Gel chromatography revealed that beta-endorphin-like immunoreactivity in CSF consisted of two components with elution positions compatible to those of beta-endorphin and beta-lipotropin (beta-LPH), respectively, and an additional larger molecule. The beta-endorphin level in CSF obtained from four nonendocrine patients was 17.9 +/- 2.3 pg/ml (mean +/- SE) and corresponded to 20% of beta-endorphin-like immunoreactivity. The predominant componet in CSF was either beta-LPH or the larger molecule. beta-Endorphin levels in CSF were consistently higher than those in plasma, and there seemed to be no relationship between them. One patient with Nelson's syndrome had a CSF beta-endorphin level of 14.8 pg/ml, although the plasma level was 784 pg/ml. On the other hand, one patient under glucocorticoid treatment had a CSF beta-endorphin level of 13.0 pg/ml and an undetectably low plasma level. It is concluded that 1) beta-endorphin-like immunoreactivity consists of beta-endorphin, beta-LPH, and possibly the precursor molecule; and 2) there exists marked dissociation between plasma and CSF beta-endorphin levels, suggesting the possible central nervous system origin of beta-endorphin in CSF.


Assuntos
Endorfinas/líquido cefalorraquidiano , Adulto , Idoso , Cromatografia em Gel , Endorfinas/sangue , Endorfinas/isolamento & purificação , Humanos , Pessoa de Meia-Idade , Radioimunoensaio
15.
J Clin Endocrinol Metab ; 52(1): 42-9, 1981 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-6256404

RESUMO

Regulation of secretion of ACTH-, beta-endorphin-, and gamma-melanotropin-like immunoreactivities (ACTH-LI, beta-EP-LI, and gamma-MSH-LI, respectively) was studied by using a perfused Sephadex column containing dispersed pituitary tumor cells obtained from three patients with Cushing's disease. Serial dilution of the perfusion medium gave lines parallel to the standard curve in each RIA for ACTH, beta-EP and gamma-MSH, suggesting that immunoreactive materials in the medium are immunologically indistinguishable from the authentic peptides. Gel exclusion chromatography of the medium revealed the existence of ACTH, beta-lipotropin (beta-LPH), beta-EP, and their possible precursor protein. gamma-MSH-LI consists of a major peak of big gamma-MSH eluted near the elution position of beta-LPH, suggesting the entire or nearly entire N-terminal portion of the precursor molecule. The addition of lysine vasopressin and rat median eminence extracts (MEE) to the perfusion system concomitantly enhanced the release of ACTH-LI, beta-EP-LI, and gamma-MSH-LI, although the dose-response relationship was clear-cut only in the case of MEE. TRH and LRH also elicited the concomitant release of these peptides in one patient, in whom combined administration of TRH and LRH significantly augmented plasma cortisol levels when studied preoperatively. The molar ratio of ACTH-LI to beta-EP-LI was approximately 1.0, whereas gamma-MSH-LI was about one fourth of ACTH-LI when compared on a weight basis. These results indicate that 1) ACTH-producing human pituitary adenomas concomitantly secrete ACTH, beta-LPH, beta-EP, and big gamma-MSH, and 2) lysine vasopressin, MEE, TRH, and LRH act directly on pituitary cells to stimulate the release of these peptides.


Assuntos
Adenoma/metabolismo , Hormônio Liberador de Gonadotropina/farmacologia , Lipressina/farmacologia , Neoplasias Hipofisárias/metabolismo , Hormônio Liberador de Tireotropina/farmacologia , Hormônio Adrenocorticotrópico/metabolismo , Adulto , Animais , Síndrome de Cushing , Endorfinas/metabolismo , Feminino , Humanos , Técnicas In Vitro , Masculino , Eminência Mediana/fisiologia , Hormônios Estimuladores de Melanócitos/metabolismo , Perfusão , Ratos
16.
Virchows Arch ; 437(4): 388-95, 2000 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11097364

RESUMO

BUF/Mna rats spontaneously develop thymomas and cause muscle weakness of hind legs at an advanced age. This rat strain has been recognized as a suitable animal model for human myasthenia gravis or related myopathies. To characterize the structural changes of neuromuscular junctions (NMJs) in BUF/Mna rats, subneural apparatuses (SNAs) of extensor digitorum longus muscles of young-adult (4-month-old) and aged (22- to 25-month-old) male rats were examined using scanning and transmission electron microscopy. The SNAs of NMJs in young rats consist of complex labyrinthine gutters with numerous slit-like junctional folds. SNAs in aged BUF/Mna rats, however, are characterized by: (1) a group of cup-like depressions with very wide slit-like junctional folds in relatively large muscle fibers (the major type), (2) the presence of slit-like folds on the flat sarcoplasm outside the cup-like depressions or on the protruded sarcoplasm, and (3) winding gutters or a small number of round depressions with poorly developed synaptic folds in small and medium-sized muscle fibers (the minor type). Since similar structural changes have been reported in dystrophic mice or normally aged rats, it is suggested that both the slowly progressing muscle atrophy and age-dependent turnover of muscle fibers may occur in the aged BUF/Mna rats.


Assuntos
Envelhecimento/patologia , Fibras Musculares Esqueléticas/ultraestrutura , Junção Neuromuscular/ultraestrutura , Timoma/ultraestrutura , Neoplasias do Timo/ultraestrutura , Animais , Masculino , Microscopia Eletrônica , Ratos
17.
Peptides ; 5(5): 913-6, 1984.
Artigo em Inglês | MEDLINE | ID: mdl-6095219

RESUMO

Using a radioimmunoassay for gamma 3-melanotropin (gamma 3-MSH), gamma-melanotropin-like immunoreactivity (gamma-MSH-LI) was detected in plasma extracts of normal subjects before and after metyrapone administration. Plasma gamma-MSH-LI from four normal men rose significantly after a single oral administration of metyrapone (30 mg/kg of body weight). Gel chromatographic study of plasma extract after metyrapone administration showed a single peak of gamma-MSH-LI near the elution position of mouse 16K fragment, however smaller forms of gamma-MSH-LI were not detected.


Assuntos
Hormônios Estimuladores de Melanócitos/sangue , Hormônio Adrenocorticotrópico/sangue , Adulto , Animais , Cromatografia em Gel , Endorfinas/sangue , Humanos , Masculino , Metirapona , Camundongos , Peso Molecular , Radioimunoensaio/métodos , Valores de Referência , beta-Endorfina
18.
Regul Pept ; 2(3): 201-8, 1981 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-6114520

RESUMO

Using a highly specific and sensitive radioimmunoassay for dynorphin(1-13), dynorphin-like immunoreactivity (dynorphin-LI) was detected in rat pituitary and hypothalamus. Gel chromatographic studies on Sephadex G-50 revealed three components of dynorphin-LI with molecular weights of approximately 7500-9500 (big dynorphin), 3500-5500 (intermediate dynorphin) and 1600-1900 (small dynorphin), the latter of which eluted at the same position as authentic dynorphin contamination in porcine ACTH extracts (Sigma). Dynorphin-LI in rat anterior pituitary existed mainly as big dynorphin, whereas dynorphin-LI in rat intermediate-posterior pituitary and hypothalamus eluted mainly at the position of authentic small dynorphin.


Assuntos
Endorfinas/análise , Hipotálamo/análise , Hipófise/análise , Animais , Cromatografia em Gel , Dinorfinas , Masculino , Peso Molecular , Fragmentos de Peptídeos/análise , Adeno-Hipófise/análise , Neuro-Hipófise/análise , Radioimunoensaio , Ratos
19.
Eur J Pharmacol ; 64(2-3): 161-4, 1980 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-6249615

RESUMO

gamma-Melanotropin (gamma-MSH), a putative peptide residing in the cryptic N-terminal portion of ACTH-beta-LPH precursor, shares several amino acid residues with alpha-MSH or beta-MSH. The present study revealed that gamma-MSH and structurally related peptides had as potent an affinity for rat brain opiate receptors as did ACTH1-24 when 3H-naloxone was used as a ligand. Thus, gamma-MSH and structurally related peptides may have physiological significance in the activities of the CNS.


Assuntos
Hormônio Adrenocorticotrópico/metabolismo , Hormônios Estimuladores de Melanócitos/metabolismo , Receptores Opioides/metabolismo , beta-Lipotropina/metabolismo , Animais , Encéfalo/efeitos dos fármacos , Encefalinas/metabolismo , Técnicas In Vitro , Masculino , Hormônios Estimuladores de Melanócitos/farmacologia , Naloxona/metabolismo , Ratos , Sódio/farmacologia
20.
J Orthop Res ; 12(3): 447-9, 1994 May.
Artigo em Inglês | MEDLINE | ID: mdl-8207599

RESUMO

We used scanning electron microscopy to examine the microcirculation in the vertebral end-plates of rabbits. The arteriola arborizes and swells at the end-plate and then coils to make a microvessel loop. This loop is the structure we refer to as a vascular bud. We suggest that these loop structures of the capillaries play a major role in the nutrition of the intervertebral discs.


Assuntos
Coluna Vertebral/irrigação sanguínea , Animais , Vasos Sanguíneos/ultraestrutura , Microscopia Eletrônica de Varredura , Coelhos
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