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1.
Ann Gen Psychiatry ; 22(1): 38, 2023 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-37814328

RESUMO

BACKGROUND: The coronavirus disease 2019 (COVID-19) pandemic was reported to have increased depression among university students which was associated with impairments in their campus lives. This study examined changes in depressive states among Japanese university students during the COVID-19 pandemic. METHODS: A secondary data analysis from a factorial randomized controlled trial involving smartphone-based cognitive-behavioral therapy was performed. Six cohorts (N = 1626) underwent an 8-week intervention during the spring or autumn of 2019-2021, with a 9-month follow-up. We evaluated participants' depressive states weekly using the Patient Health Questionnaire-9 (PHQ-9) during the intervention, with monthly evaluations thereafter. The follow-up periods included Japan's four states of emergency (SOEs) to control COVID-19. Hypothesizing that SOEs caused a sudden worsening of depressive states, Study 1 compared the cohorts' PHQ-9 scores, and Study 2 employed time series analysis with a mixed-effects model to estimate identified changes in PHQ-9 scores. RESULTS: Although no changes in depressive states were observed in relation to the SOEs, Study 1 identified sudden increases in PHQ-9 scores at the 28-week evaluation point, which corresponded to the beginning of the new academic year for the three autumn cohorts. In contrast, the three spring cohorts did not exhibit similar changes. Study 2 showed that, for all three autumn cohorts (n = 522), the 0.60-point change was significant (95% CI 0.42-0.78; p < .001) at 28 weeks; that is, when their timeline was interrupted. CONCLUSIONS: While the results do not indicate any notable impact of the SOEs, they highlight the influence of the new academic year on university students' mental health during COVID-19. Trial registration UMIN, CTR-000031307. Registered on February 14, 2018.

2.
Br J Cancer ; 109(7): 1899-903, 2013 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-24002606

RESUMO

BACKGROUND: An increased body mass index (BMI) is significantly associated with favourable prognosis in renal cell carcinoma (RCC). This study investigated the associations among sex, BMI, and prognosis in clear cell RCC patients. METHODS: We retrospectively analysed 435 patients with clear cell RCC who underwent a nephrectomy. The associations among sex, BMI, clinicopathologic factors, and cancer-specific survival (CSS) were analysed. RESULTS: As a continuous variable, increased BMI was associated with higher CSS rate by univariate analysis in the whole population (hazard ratio, 0.888 per kg m(-2); 95% confidence interval, 0.803-0.982; P=0.021). A sub-population analysis by sex demonstrated that BMI was significantly associated with CSS in men (P=0.004) but not in women (P=0.725). Multivariate analysis revealed BMI to be an independent predictor of CSS in only men. CONCLUSION: Body mass index was significantly associated with clear cell RCC prognosis. However, the clinical value of BMI may be different between men and women.


Assuntos
Fatores Etários , Índice de Massa Corporal , Carcinoma de Células Renais/mortalidade , Neoplasias Renais/mortalidade , Caracteres Sexuais , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma de Células Renais/metabolismo , Carcinoma de Células Renais/cirurgia , Feminino , Humanos , Neoplasias Renais/metabolismo , Neoplasias Renais/cirurgia , Masculino , Pessoa de Meia-Idade , Nefrectomia , Prognóstico , Estudos Retrospectivos , Taxa de Sobrevida , Resultado do Tratamento
4.
J Clin Invest ; 82(1): 110-4, 1988 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-2839542

RESUMO

The effects of corticotropin-releasing hormone (CRH) and dexamethasone on proopiomelanocortin (POMC) mRNA levels in cultured pituitary adenoma cells were studied in 10 patients with Cushing's disease. As a control, POMC mRNA levels in cells from nonadenomatous tissues were examined in four patients. Human POMC mRNA in the cells was analyzed by Northern blot hybridization. Human POMC DNA probe hybridized with only a single size class of RNA (approximately 1,200 nucleotides) from the adenoma and nonadenoma cells of each patient. The size of POMC mRNA did not change through the culture or after incubation with CRH or dexamethasone. CRH increased POMC mRNA levels in these cells in a dose- and time-dependent manner. The minimum concentration of CRH required to elevate POMC mRNA levels in these cells exposed for 15 h was 0.1 nM. The minimum duration of 1 nM CRH treatment required to increase these levels was 3 h under our conditions. Inhibitory effects of 1 and 10 micrograms/dl dexamethasone on ACTH release and POMC mRNA levels in nonadenoma cells were greater than those in adenoma cells. These results suggest the following: (a) that the mRNA in cultured pituitary adenoma cells is qualitatively the same as that in vivo; (b) that responses of mRNA levels to CRH are time- and dose-dependent; and (c) that adenoma cells resist the inhibitory effect of dexamethasone on POMC mRNA levels and ACTH release.


Assuntos
Adenoma/metabolismo , Hormônio Liberador da Corticotropina/farmacologia , Dexametasona/farmacologia , Neoplasias Hipofisárias/metabolismo , Pró-Opiomelanocortina/metabolismo , RNA Mensageiro/metabolismo , Hormônio Adrenocorticotrópico/metabolismo , Humanos , Hibridização de Ácido Nucleico , Adeno-Hipófise , RNA Mensageiro/isolamento & purificação , Fatores de Tempo , Células Tumorais Cultivadas
5.
J Clin Invest ; 76(5): 2026-9, 1985 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-2997301

RESUMO

Plasma immunoreactive corticotropin-releasing factor (I-CRF) levels were determined by using a human CRF radioimmunoassay and an immunoaffinity procedure. The basal plasma I-CRF level in normal subjects was 6 +/- 0.5 pg/ml (mean +/- SD). We found that most plasma I-CRF levels were affected by stress, negative feedback, and circadian rhythm. Basal I-CRF levels were high in patients with Addison's disease, Nelson's syndrome, hypopituitarism stemming from pituitary macroadenoma, and CRF- and adrenocorticotropic hormone-producing tumors. A very low, but significant, amount of I-CRF was detected (1-3 pg/ml) in patients with Cushing's syndrome, in corticosteroid-treated patients, and in a patient with hypothalamic hypopituitarism. These results suggest that a major component of plasma I-CRF is of hypothalamic origin, however, other extrahypothalamic tissues cannot be ruled out as a minor source of plasma I-CRF.


Assuntos
Doenças das Glândulas Suprarrenais/sangue , Hormônio Liberador da Corticotropina/sangue , Doenças Hipotalâmicas/sangue , Doenças da Hipófise/sangue , Hormônio Adrenocorticotrópico/sangue , Adulto , Cromatografia Líquida de Alta Pressão , Síndrome de Cushing/sangue , Humanos , Hidrocortisona/sangue , Insulina/farmacologia , Metirapona , Radioimunoensaio
6.
Oncogene ; 19(51): 5842-50, 2000 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-11127814

RESUMO

Meltrin alpha/ADAM12 is a member of the ADAM/MDC family proteins characterized by the presence of metalloprotease and disintegrin domains. This protein also contains a single transmembrane domain and a relatively long cytoplasmic domain containing several proline-rich sequences. These sequences are compatible with the consensus sequences for binding the Src homology 3 (SH3) domains. To determine whether the proline-rich sequences interact with SH3 domains in several proteins, binding of recombinant SH3 domains to the meltrin alpha cytoplasmic domain was analysed by pull-down assays. The SH3 domains of Src and Yes bound strongly, but that of Abl or phosphatidylinositol 3-kinase p85 subunit did not. Full-length Grb2/Ash bound strongly, whereas its N-terminal SH3 domain alone did less strongly. Src and Grb2 in bovine brain extracts also bound to meltrin alpha cytoplasmic domain on affinity resin. Furthermore, immunoprecipitation with a monoclonal antibody to meltrin alpha resulted in coprecipitation of Src and Grb2 with meltrin alpha in cell extracts, suggesting that Src and Grb2 are associated in vivo with meltrin alpha cytoplasmic domain. This notion was also supported by the findings that exogenously expressed meltrin cytoplasmic domain coexisted with Src and Grb2 on the membrane ruffles. The C-terminal Tyr901 of meltrin alpha was phosphorylated both in vitro and in cultured cells by v-Src. These results may imply that meltrin alpha cytoplasmic domain is involved in a signal transduction for some biological function through the interaction with SH3-containing proteins.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal , Proteínas de Membrana/metabolismo , Proteínas Musculares/metabolismo , Proteína Oncogênica pp60(v-src)/metabolismo , Proteínas/metabolismo , Domínios de Homologia de src/fisiologia , Proteínas ADAM , Proteína ADAM12 , Sequência de Aminoácidos , Animais , Sítios de Ligação , Encéfalo/metabolismo , Bovinos , Células Cultivadas , Galinhas , Citoplasma/metabolismo , Proteína Adaptadora GRB2 , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C3H , Dados de Sequência Molecular , Fragmentos de Peptídeos/metabolismo , Fosforilação , Testes de Precipitina , Estrutura Terciária de Proteína , Proteínas Proto-Oncogênicas c-yes , Coelhos , Ratos , Extratos de Tecidos/química , Extratos de Tecidos/metabolismo , Tirosina/metabolismo , Quinases da Família src/metabolismo
7.
J Neurosci ; 20(5): 2003-10, 2000 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-10684901

RESUMO

Plasmin is converted from its zymogen plasminogen by tissue type or urokinase type plasminogen activator (PA) and degrades many components of the extracellular matrix (ECM). To explore the possibility that the PA-plasmin system regulates synaptic plasticity, we investigated the effect of plasmin on degradation of ECM and synaptic plasticity by using organotypic hippocampal cultures. High-frequency stimulation produced long-term potentiation (LTP) in control slices, whereas the potentiation was induced but not maintained in slices pretreated with 100 nM plasmin for 6 hr. The baseline synaptic responses were not affected by pretreatment with plasmin. The impairment of LTP maintenance was not observed in slices pretreated with 100 nM plasmin for 6 hr, washed, and then cultured for 24-48 hr in the absence of plasmin. To identify substrates of plasmin, the expression of three major components of ECM, laminin, fibronectin, and type IV collagen, was investigated by immunofluorescence imaging. The three ECM components were widely distributed in the hippocampus, and only laminin was degraded by plasmin pretreatment. The expression level of laminin returned to normal levels when the slices were cultured for 24-48 hr after washout of plasmin. Furthermore, preincubation with anti-laminin antibodies prevented both the degradation of laminin and the impairment of LTP maintenance by plasmin. These results suggest that the laminin-mediated cell-ECM interaction may be necessary for the maintenance of LTP.


Assuntos
Fibrinolisina/farmacologia , Hipocampo/metabolismo , Laminina/metabolismo , Potenciação de Longa Duração/fisiologia , Animais , Potenciais Pós-Sinápticos Excitadores/efeitos dos fármacos , Potenciais Pós-Sinápticos Excitadores/fisiologia , Matriz Extracelular/metabolismo , Imunofluorescência , Hipocampo/citologia , Laminina/análise , Potenciação de Longa Duração/efeitos dos fármacos , Plasticidade Neuronal/fisiologia , Neurônios/química , Neurônios/citologia , Neurônios/enzimologia , Técnicas de Cultura de Órgãos , Ratos , Ratos Wistar , Ativador de Plasminogênio Tipo Uroquinase/metabolismo
8.
Endocrinology ; 118(1): 459-61, 1986 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-3000747

RESUMO

Effects of ACTH and ACTH fragments on immunoreactive corticotropin-releasing factor (I-CRF) release were examined by utilizing rat hypothalamic perifusion system and a rat CRF RIA. ACTH-(1-39) had a dose-related inhibitory effect on I-CRF release. Mean percent inhibition of I-CRF release was 52, 55, 49, 30 and less than 5 percent by ACTH-(1-39), ACTH-(1-24), alpha-MSH and ACTH-(18-39) at 2.2 nM concentrations, respectively. These results suggest the presence of a negative short-loop feedback mechanism, and also that the active core is contained within the ACTH-(1-17) structure.


Assuntos
Hormônio Adrenocorticotrópico/farmacologia , Hormônio Liberador da Corticotropina/metabolismo , Hipotálamo/metabolismo , Animais , Peptídeo da Parte Intermédia da Adeno-Hipófise Semelhante à Corticotropina , Cosintropina/farmacologia , Hipotálamo/efeitos dos fármacos , Técnicas In Vitro , Cinética , Masculino , Hormônios Estimuladores de Melanócitos/farmacologia , Fragmentos de Peptídeos/farmacologia , Ratos
9.
Endocrinology ; 120(4): 1391-6, 1987 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-3030699

RESUMO

Immunoreactive ACTH (I-ACTH) levels in the rat anterior pituitary and plasma, and immunoreactive corticotropin-releasing factor (I-CRF) concentrations in the median eminence (ME) and plasma were determined after adrenalectomy and in insulin-induced hypoglycemia. I-CRF was detected in plasma from normal rats (mean +/- SD, 5.6 +/- 0.9 pg/ml; n = 6). Gel filtration chromatography of I-CRF from pooled plasma of these rats revealed a single peak which eluted in the position of authentic rat CRF. I-CRF levels in ME and I-ACTH levels in anterior pituitary decreased immediately after adrenalectomy, then gradually increased to high levels 14 days after surgery. Plasma I-CRF and I-ACTH concentrations increased immediately after surgery, slightly decreased to near the control levels at 24 h, and then increased to high concentrations 14 days after surgery. Plasma and ME I-CRF levels 14 days after adrenalectomy, followed by daily dexamethasone replacement, were almost the same as control levels. In insulin-induced hypoglycemia, plasma I-ACTH and I-CRF concentrations increased and ME I-CRF content decreased at 30 and 60 min. These results suggest that plasma I-CRF levels reflect changes in hypothalamic CRF levels.


Assuntos
Hormônio Liberador da Corticotropina/sangue , Adrenalectomia , Hormônio Adrenocorticotrópico/sangue , Hormônio Adrenocorticotrópico/metabolismo , Animais , Cromatografia em Gel , Hormônio Liberador da Corticotropina/metabolismo , Hipoglicemia/induzido quimicamente , Hipoglicemia/metabolismo , Hipotálamo/metabolismo , Insulina , Masculino , Eminência Mediana/metabolismo , Adeno-Hipófise/metabolismo , Radioimunoensaio , Ratos , Ratos Endogâmicos
10.
Endocrinology ; 123(3): 1371-5, 1988 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-2841092

RESUMO

To study the effect of acute stress on CRF release and synthesis in rat hypothalamus, ACTH levels in plasma, CRF contents in the median eminence (ME), and CRF mRNA levels in the hypothalamus without ME and cerebral cortex were determined after insulin-induced hypoglycemia. Plasma ACTH levels increased at 30 and 60 min, while ME CRF content decreased at 30 and 60 min, then returned to the control level at 90 min. Hybridization with a cRNA probe revealed a single size class of CRF mRNA in the hypothalamus and cerebral cortex (approximately 1300 nucleotides), and the size of CRF mRNA in these tissues did not change during the experimental period. CRF mRNA levels in the hypothalamus increased to 130% of the control value at 30 min and reached a peak (186% of the control value) at 120 min, but these levels in the cerebral cortex did not change. These results suggest that insulin-induced hypoglycemia stimulates CRF synthesis by increasing CRF mRNA levels in the hypothalamus as well as CRF release, and that release and synthesis of CRF in the cerebral cortex are independent of those in the hypothalamus.


Assuntos
Hormônio Adrenocorticotrópico/sangue , Hormônio Liberador da Corticotropina/genética , Hipoglicemia/metabolismo , Hipotálamo/metabolismo , Insulina/farmacologia , RNA Mensageiro/metabolismo , Animais , Hipoglicemia/induzido quimicamente , Hipotálamo/efeitos dos fármacos , Masculino , Eminência Mediana/efeitos dos fármacos , Eminência Mediana/metabolismo , Plasmídeos , RNA Mensageiro/efeitos dos fármacos , RNA Mensageiro/genética , Ratos , Ratos Endogâmicos
11.
Endocrinology ; 124(3): 1444-9, 1989 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-2537181

RESUMO

To examine the effects of the cAMP-independent protein kinase-C system and interleukin-1 (IL-1) on secretion of ACTH and POMC gene expression in cultured rat anterior pituitary (AP) cells, AP cells were incubated with CRF, 8-bromo-cAMP, arginine vasopressin, angiotensin II, norepinephrine, and phorbol 12-myristate 13-acetate. After 15 h of incubation, CRF and 8-bromo-cAMP increased both ACTH release and the POMC mRNA level. Arginine vasopressin, angiotensin II, norepinephrine, or phorbol 12-myristate 13-acetate stimulated ACTH release but failed to increase basal or CRF-stimulated POMC mRNA levels. Human recombinant IL-1 alpha and -beta increased neither ACTH release nor POMC mRNA levels after 3 h of incubation. After 15 h of incubation, 100 pM to 10 nM IL-1 alpha and -beta increased ACTH release. However, POMC mRNA levels were significantly elevated only by 10 pM IL-1 beta. These results suggest that the CRF-cAMP system plays a major role in both ACTH release and expression of the POMC gene in AP cells, but the cAMP-independent protein kinase-C system contributes only to ACTH release; that acute stimulation of ACTH release from AP with IL-1 administration is not due to direct action of IL-1 at the pituitary level; that chronic exposure of AP cells to IL-1 alpha or -beta can stimulate ACTH release; and that the direct effects of IL-1 alpha and -beta on POMC gene expression, if any, seem to be minimal.


Assuntos
Hormônio Adrenocorticotrópico/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Interleucina-1/farmacologia , Adeno-Hipófise/metabolismo , Pró-Opiomelanocortina/genética , Proteína Quinase C/metabolismo , 8-Bromo Monofosfato de Adenosina Cíclica/farmacologia , Angiotensina II/farmacologia , Animais , Arginina Vasopressina/farmacologia , Hormônio Liberador da Corticotropina/farmacologia , Norepinefrina/farmacologia , Adeno-Hipófise/efeitos dos fármacos , RNA Mensageiro/biossíntese , Ratos , Acetato de Tetradecanoilforbol/farmacologia
12.
Endocrinology ; 122(4): 1231-5, 1988 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-2831025

RESUMO

To study the effect of acute stress on ACTH secretion and synthesis in rat pituitary and hypothalamus, ACTH content and POMC mRNA levels (measured by use of Northern blot analysis) in these tissues as well as the levels of ACTH in plasma and those of CRF in the hypothalamus were determined after insulin-induced hypoglycemia. Plasma ACTH levels increased at 30 and 60 min. ACTH levels in the anterior pituitary lobe (AP) decreased at 30 min, and then returned to control levels at 60 min. No change was seen in the intermediate-posterior pituitary (IP) or the hypothalamus after insulin injection. CRF levels decreased at 30 and 60 min, then returned to control levels at 90 min in the medial basal hypothalamus, including the median eminence. Hybridization with a cDNA probe revealed a single size class of POMC mRNA in AP, IP, and hypothalamus, and the size of POMC mRNA in these tissues did not change during the experimental period. POMC mRNA levels in AP increased at 60 min and reached a peak at 120 min, but those in IP and hypothalamus did not change. These results suggest that 1) insulin-induced hypoglycemia stimulates both secretion and synthesis of ACTH (at least by increasing POMC mRNA levels) in the AP, and 2) the levels of ACTH and POMC mRNA in the IP and hypothalamus are not affected by insulin-induced hypoglycemia.


Assuntos
Hipoglicemia/metabolismo , Insulina/farmacologia , Adeno-Hipófise/análise , Pró-Opiomelanocortina/genética , RNA Mensageiro/análise , Hormônio Adrenocorticotrópico/sangue , Animais , Glicemia/análise , Hormônio Liberador da Corticotropina/análise , Hipotálamo/análise , Masculino , Ratos , Ratos Endogâmicos
13.
J Clin Endocrinol Metab ; 68(1): 87-93, 1989 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-2535853

RESUMO

To study possible adrenergic modulation of pituitary-adrenal responses to insulin-induced hypoglycemia and CRH we examined the effect of nonselective alpha-blockade (phentolamine) and nonselective beta-blockade (propranolol) on plasma ACTH, cortisol, and vasopressin (AVP) responses to hypoglycemia and CRH in five normal men. Infusion of propranolol or phentolamine did not alter basal plasma ACTH or cortisol levels. The propranolol infusion enhanced the stimulatory effect of hypoglycemia on ACTH, cortisol, and AVP secretion and also enhanced the stimulatory effect of CRH on ACTH and cortisol secretion. Infusion of phentolamine inhibited hypoglycemia-induced ACTH and AVP secretion, but had no effect on the stimulatory effect of CRH on ACTH and cortisol secretion. The increments of plasma ACTH and cortisol induced by an almost maximal dose of CRH (1 microgram/kg) were smaller than those induced by hypoglycemia. The propranolol-induced enhancement of the ACTH response to hypoglycemia was almost the same as the ACTH response to CRH alone. From these results we conclude that propranolol may act at the pituitary level to enhance CRH action, rather than AVP action, and that the ACTH response to hypoglycemia may be mediated by hypothalamic alpha-adrenergic activation.


Assuntos
Hormônio Adrenocorticotrópico/sangue , Hormônio Liberador da Corticotropina/farmacologia , Hipoglicemia/fisiopatologia , Insulina/farmacologia , Fentolamina/farmacologia , Propranolol/farmacologia , Glicemia/análise , Feminino , Hemodinâmica/efeitos dos fármacos , Humanos , Hidrocortisona/sangue , Insulina/sangue , Vasopressinas/sangue
14.
J Clin Endocrinol Metab ; 69(1): 38-42, 1989 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-2543693

RESUMO

Plasma CRH levels are considerably higher in women during the third trimester of pregnancy than in non-pregnant women. Most of plasma CRH in pregnant women is bound to CRH-binding protein (CRH-BP). To gain further insight into CRH physiology during pregnancy, we measured the responses of plasma ACTH and cortisol and the changes in bound and free forms of CRH in plasma after human CRH administration (2 micrograms/kg) in five pregnant (39-40 weeks of pregnancy) and five nonpregnant women. The mean basal plasma ACTH and cortisol levels in the pregnant women were higher than those in the nonpregnant women. However, the maximum increments in plasma ACTH and cortisol levels and the integrated ACTH and cortisol responses, after subtraction of the basal levels after CRH administration, were similar in the two groups. The plasma CRH half-time in the pregnant group was similar to that in the nonpregnant group. The mean basal plasma CRH level in the nonpregnant women was 1.5 +/- 0.2 (+/- SE) pmol/L, and that in the pregnant women was 360 +/- 35 pmol/L. On gel filtration chromatography, almost all of the CRH in the plasma was protein bound (320 +/- 30 pmol/L) in the pregnant women; no CRH peaks were detected in nonpregnant women because of the low plasma CRH levels. After CRH administration, the level of the bound form of plasma CRH was highest at 5 min, and then declined to a plateau at 15 min and 30 min in the pregnant women. In the nonpregnant women, protein-bound CRH also was highest at 5 min, but it progressively declined thereafter. The disappearance rate of the bound CRH in plasma from the nonpregnant women was similar to that of the second compartment of the plasma decay curves of the free CRH from both groups. We conclude that the plasma ACTH and cortisol responses to exogenous CRH are similar in pregnant and nonpregnant women, the effect of CRH-BP on the disappearance of plasma CRH is minimal, and plasma CRH-BP in pregnant women has the capacity to bind additional CRH.


Assuntos
Hormônio Adrenocorticotrópico/sangue , Hormônio Liberador da Corticotropina/farmacocinética , Hidrocortisona/sangue , Gravidez/sangue , Adulto , Sítios de Ligação , Cromatografia em Gel , Hormônio Liberador da Corticotropina/sangue , Feminino , Humanos , Radioimunoensaio
15.
J Clin Endocrinol Metab ; 64(5): 909-13, 1987 May.
Artigo em Inglês | MEDLINE | ID: mdl-3031120

RESUMO

The effect of ACTH administration on plasma CRH levels was studied. In five patients with Addison's disease and three patients with hypopituitarism, bolus iv injection of 0.25 and 0.5 mg ACTH-(1-24) reduced plasma CRH levels (that had become elevated 48 h after discontinuation of corticosteroid replacement) to near-normal levels at 30-60 min in a dose-dependent manner. Plasma immunoreactive beta-endorphin levels were similarly decreased in patients with Addison's disease. ACTH-(1-24) (0.25 and 0.5 mg) injection failed to inhibit plasma CRH levels in five normal subjects. Basal CRH release from the rat hypothalamic median eminence in vitro was inhibited by 0.22 and 2.2 nM ACTH-(1-24) and ACTH-(1-39) in a dose-dependent manner. These results suggest that in the absence of negative feedback control of ACTH secretion by glucocorticoids, ACTH can regulate its secretion by inhibition of hypothalamic CRH release.


Assuntos
Doença de Addison/fisiopatologia , Hormônio Adrenocorticotrópico/fisiologia , Hormônio Liberador da Corticotropina/metabolismo , Hipopituitarismo/fisiopatologia , Hormônio Adrenocorticotrópico/farmacologia , Adulto , Idoso , Animais , Cosintropina/sangue , Cosintropina/farmacologia , Retroalimentação , Feminino , Humanos , Hipotálamo/efeitos dos fármacos , Hipotálamo/metabolismo , Cinética , Masculino , Eminência Mediana/efeitos dos fármacos , Eminência Mediana/metabolismo , Pessoa de Meia-Idade , Ratos
16.
J Clin Endocrinol Metab ; 67(6): 1278-83, 1988 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-2848056

RESUMO

A human plasma CRH-binding protein (CRH-BP) was identified and characterized by chemical cross-linking of 125I-Tyr-hCRH to human plasma using disuccinimidyl suberate. The apparent mol wt of the cross-linked complex determined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis followed by autoradiography was approximately 43,000. The mol wt was slightly lower in the nonreduced state, suggesting the presence of intramolecular disulfide bonds. Subtracting the mol wt of 125I-Tyr-CRH, the BP appeared to have a mol wt of approximately 38,000. Binding was specific since the appearance of the 43,000 dalton band was not affected by unlabeled ACTH, vasopressin, serum albumin, or gamma-globulin, but was inhibited by unlabeled hCRH dose dependently. Pretreatment of plasma with 0.1 mol/L HCl, 0.01 mol/L NaOH, 10 mmol/L dithiothreitol, or trypsin before cross-linking abolished its ability to bind 125I-Tyr-hCRH. Rat, rabbit, or goat plasma or human cerebrospinal fluid did not bind 125I-Tyr-CRH. It is unlikely that CRH-BP is a CRH receptor, because the estimated mol wt of the CRH-BP is smaller than the reported size of CRH receptors, and the CRH-BP did not bind to ovine CRH. The binding of 125I-Tyr-CRH to CRH-BP decreased in the third trimester of pregnancy, when plasma CRH levels were markedly elevated. However, after dissociating endogenous CRH from the CRH-BP, the binding was almost the same as in nonpregnant subjects. In addition, CRH-BP inhibited CRH-induced ACTH secretion from cultured rat anterior pituitary cells. We conclude that most of the increased plasma CRH found in pregnant women is bound to CRH-BP, and so is inactive, therefore plasma ACTH levels do not increase to above the normal range.


Assuntos
Proteínas de Transporte/sangue , Hormônio Liberador da Corticotropina/sangue , Gravidez/sangue , Hormônio Adrenocorticotrópico/metabolismo , Adulto , Animais , Ligação Competitiva , Proteínas Sanguíneas/metabolismo , Proteínas de Transporte/fisiologia , Células Cultivadas , Reagentes de Ligações Cruzadas , Eletroforese em Gel de Poliacrilamida , Feminino , Humanos , Masculino , Adeno-Hipófise/metabolismo , Ligação Proteica , Radioimunoensaio , Ratos
17.
Am J Surg Pathol ; 12(7): 559-66, 1988 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-3389453

RESUMO

Neoplasms of all the adrenal parenchymatous elements [i.e., a compound adrenal medullary tumor (MT) consisting of pheochromocytoma (Pheo) and ganglioneuroma (GN) and a cortical adenoma] were found in the right adrenal gland of a 53-year-old man. A mature GN element was predominant in the MT, and nodules of small polygonal Pheo cells were scattered in GN. No neuroblastomatous element or malignant Pheo was found. The cortical adenoma consisted of compact cells and clear cells; it showed 3 beta hydroxysteroid dehydrogenase, glucose-6-phosphate dehydrogenase, and succinate dehydrogenase activity. The nonneoplastic cortex was slightly atrophic and showed weaker activity of the enzymes, suggesting that the adenoma was cortisol-producing. The cortex surrounding the MT was invaded and replaced by either GN or Pheo. In some places, however, hypertrophic compact cells constituted the cortex and were in contact with ACTH-immunoreactive chromaffin cells. A few of the latter were also positive for other proopiomelanocortin (POMC)-derived peptides. Pheo cells in the other parts were negative for POMC-derived peptides.


Assuntos
Adenoma/diagnóstico , Neoplasias do Córtex Suprarrenal/diagnóstico , Neoplasias das Glândulas Suprarrenais/diagnóstico , Medula Suprarrenal , Ganglioneuroma/diagnóstico , Feocromocitoma/diagnóstico , Histocitoquímica , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade
18.
Neuroscience ; 81(1): 1-8, 1997 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-9300395

RESUMO

Changes in membrane potentials were recorded from rat hippocampal slices with a voltage-sensitive dye using a real-time optical recording system, which had high spatial resolution of 128 x 128 points with a high time resolution of 0.6 ms. Serial excitatory propagation was recorded in the dentate gyrus. CA3 and CA1 after stimulation of the perforant pathway, and the optical signals were clearly divided into two components in the dentate gyrus adjacent to the stimulus site. The slow component was suppressed in Ca(2+)-free solution, but the fast component in the molecular layer was not affected. However, the application of 1 microM tetrodotoxin fully abolished both components. These results suggest that the fast and slow components mainly reflect Na(+)-dependent action potentials and excitatory postsynaptic potentials, respectively. The excitatory response duration in the stratum radiatum of CA3 was significantly longer than that in other hippocampal areas. The long-lasting excitation in CA3 is probably related to the CA3 associational projections, because direct stimulation of CA3 pyramidal cell layer also produced similar results. The long-lasting dendritic excitation is probably important to integrate synaptic transmission and may be related to epileptogenesis. When long-term potentiation was induced by a tetanic stimulation (100 Hz for 1 s), the onset latency in the stratum radiatum of CA1 was reduced to as much as 65%, suggesting an increase of excitatory propagation. The analysis of the spatial-temporal optical signals contributes to understanding information processes in the hippocampus, related to learning and memory including long-term potentiation.


Assuntos
Hipocampo/citologia , Hipocampo/fisiologia , Sinapses/fisiologia , Animais , Cálcio/farmacologia , Corantes , Estimulação Elétrica , Ativação do Canal Iônico/fisiologia , Aprendizagem/fisiologia , Potenciação de Longa Duração/fisiologia , Masculino , Potenciais da Membrana/efeitos dos fármacos , Potenciais da Membrana/fisiologia , Memória/fisiologia , Vias Neurais , Plasticidade Neuronal/fisiologia , Dispositivos de Armazenamento Óptico , Técnicas de Cultura de Órgãos , Ratos , Ratos Wistar , Tetrodotoxina/farmacologia
19.
J Biochem ; 128(6): 941-9, 2000 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11098136

RESUMO

Meltrin alpha (ADAM12) is a member of the ADAM (MDC) protein family characterized by the presence of metalloprotease and disintegrin domains. ADAM proteins contain single transmembrane domains, and the processed mature proteins are postulated to span the plasma membrane. It has been reported that transfection of a truncated meltrin alpha cDNA lacking the prodomain and metalloprotease domain promotes skeletal muscle cell fusion. We show here that meltrin alpha was constitutively expressed in both undifferentiated and differentiated C2 skeletal muscle cells and also in fibroblasts. Both its precursor and processed mature forms were present in these cells. Thus, meltrin alpha may play general roles in addition to its roles in myogenesis. Since endogenous meltrin alpha cannot be detected by immunofluorescence microscopy, we examined the location of the exogenously expressed protein by transfection. Unexpectedly, the exogenously expressed meltrin alpha was located to a network structure of the endoplasmic reticulum (ER) but not to the plasma membrane. Cell fractionation revealed that the intrinsic mature protein was associated with the plasma membrane. However, the exogenously expressed protein remained unprocessed. These results seem to imply that the exogenously expressed meltrin alpha is not translocated from the ER to the trans-Golgi network, where a processing enzyme resides, and that it is consequently not converted to the mature form. Thus, the transfected meltrin alpha is unlikely to exert its physiological functions. Conversely, the ER may serve as a reservoir of the latent form of intrinsic meltrin alpha.


Assuntos
Retículo Endoplasmático/metabolismo , Proteínas de Membrana/metabolismo , Proteínas Musculares/metabolismo , Proteínas ADAM , Proteína ADAM12 , Animais , Sequência de Bases , Diferenciação Celular , Linhagem Celular , Membrana Celular/metabolismo , Primers do DNA , Fibroblastos/metabolismo , Camundongos
20.
Cancer Chemother Pharmacol ; 11 Suppl: S47-50, 1983.
Artigo em Inglês | MEDLINE | ID: mdl-6605813

RESUMO

The relapse rate of bladder cancer (transitional cell Ca) is said to be about 45%-80% even after tumor resection. Multidisciplinary treatment was designed and studied to prevent such recurrence. This treatment was designed to have three steps: induction, consolidation, and maintenance therapy. Following surgical tumor removal, OK-432 and Adriamycin (ADM) were administered as consolidation therapy, followed by administration of PSK and carboquone (CQ) in small amounts as maintenance therapy continuously for about 3 years, and the course was observed. In both consolidation and maintenance groups various non-specific immunoparameters were superior in groups receiving combined immunotherapeutic agents. Thus, the use of immunotherapeutic agents in combination with chemotherapeutic agents was considered to be effective. The 3-year recurrence rate was only 8% in the multidisciplinary treatment group, while that in the non-multidisciplinary treatment group was 61%. This approach, especially with chemoimmunotherapy (ADM and OK-432) as a consolidation therapeutic mode, is therefore considered to be useful for the prevention of recurrence.


Assuntos
Produtos Biológicos/administração & dosagem , Carcinoma de Células de Transição/tratamento farmacológico , Doxorrubicina/administração & dosagem , Recidiva Local de Neoplasia/prevenção & controle , Picibanil/administração & dosagem , Neoplasias da Bexiga Urinária/tratamento farmacológico , Adjuvantes Imunológicos/administração & dosagem , Idoso , Alopecia/induzido quimicamente , Carbazilquinona/administração & dosagem , Antígeno Carcinoembrionário/análise , Carcinoma de Células de Transição/imunologia , Carcinoma de Células de Transição/mortalidade , Terapia Combinada , Doxorrubicina/efeitos adversos , Feminino , Seguimentos , Humanos , Imunidade Celular , Imunoglobulina G/análise , Masculino , Pessoa de Meia-Idade , Proteoglicanas/administração & dosagem , Linfócitos T/imunologia , Neoplasias da Bexiga Urinária/imunologia , Neoplasias da Bexiga Urinária/mortalidade
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