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1.
Public Health ; 224: 98-105, 2023 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-37742586

RESUMO

OBJECTIVES: Lifestyle behaviours associated with the incidence of type 2 diabetes mellitus (T2DM) need further clarification using health insurance data. STUDY DESIGN: This is a cohort study. METHODS: In 2015, 193,246 participants aged 40-74 years attended the specific health checkups and were observed up to 2020 in Fukushima, Japan. Using the principal component analysis, we identified two patterns from ten lifestyle behaviour questions, namely, the "diet-smoking" pattern (including smoking, alcohol drinking, skipping breakfast, eating fast, late dinner, and snacking) and the "physical activity-sleep" pattern (including physical exercise, walking equivalent activity, walking fast, and sufficient sleep). Then, individual pattern scores were calculated; the higher the scores, the healthier the behaviours. RESULTS: The accumulative incidence rate of T2DM was 630.5 in men and 391.9 in women per 100,000 person-years in an average of 4 years of follow-up. Adjusted for the demographic and cardiometabolic factors at the baseline, the hazard ratio (95% confidence interval) of the highest versus lowest quartile scores of the "diet-smoking" pattern for T2DM risk was 0.82 (0.72, 0.92; P for trend = 0.002) in men and 0.87 (0.76, 1·00; P for trend = 0.034) in women; that of the "physical activity-sleep" pattern was 0.92 (0.82, 1·04; P for trend = 0.0996) in men and 0.92 (0.80, 1·06; P for trend = 0.372) in women. The "physical activity-sleep" pattern showed a significant inverse association in non-overweight men. CONCLUSIONS: Lifestyle behaviour associated with a healthy diet and lack of smoking may significantly lower the risk of T2DM in middle-aged Japanese adults.

2.
J Neonatal Perinatal Med ; 10(2): 147-155, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28409755

RESUMO

OBJECTIVE: To investigate the relationships between serum cytokine concentrations and chorioamnionitis (CAM) and CAM-related bronchopulmonary dysplasia (BPD) in premature infants. METHODS: Serum was collected at 0 and 7 days after birth from 36 premature infants born at <32 weeks of gestation. We examined the relationships between 30 cytokine concentrations and CAM, BPD, and other perinatal factors. RESULTS: On day 0, GM-CSF, IL-15, IL-17, IL-2, IL-2R, VEGF, and MIG concentrations were significantly higher in the CAM group (n = 17) than in the non-CAM group (n = 19). These concentrations had decreased by day 7 and were similar in both groups. The IL-12p70 concentration on day 0 was significantly lower in the BPD group (n = 16) than in the non-BPD group (n = 15). BPD incidence was similar between the CAM and non-CAM groups. CONCLUSIONS: These data support the hypothesis that intrauterine inflammation is not a primary risk factor for BPD. The immunological environment at birth or soon after, rather than intrauterine fetal inflammation (e.g., CAM), is a primary risk factor for BPD onset in preterm infants. Decreased inflammatory responses are particularly relevant, as indicated by the relationship between BPD and low serum IL-12p70 concentrations on day 0.


Assuntos
Displasia Broncopulmonar/sangue , Corioamnionite/sangue , Citocinas/sangue , Doenças do Recém-Nascido/sangue , Biomarcadores , Displasia Broncopulmonar/imunologia , Displasia Broncopulmonar/fisiopatologia , Corioamnionite/imunologia , Corioamnionite/fisiopatologia , Feminino , Humanos , Imunidade Inata , Recém-Nascido , Doenças do Recém-Nascido/imunologia , Doenças do Recém-Nascido/fisiopatologia , Recém-Nascido Prematuro/sangue , Masculino , Valor Preditivo dos Testes , Gravidez , Estudos Retrospectivos , Fatores de Risco
3.
Transfus Med ; 24(5): 305-10, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25224311

RESUMO

BACKGROUND: Despite improvements in first-line therapies, the outcomes of relapsed or refractory childhood acute leukaemia that has not achieved complete remission after relapse, has relapsed after stem cell transplantation (SCT), has primary induction failure and has relapsed with a very unfavourable cytogenetic risk profile, are dismal. OBJECTIVES AND METHODS: We evaluated the feasibility and efficacy of T-cell-replete haploidentical peripheral blood stem cell transplantation (haplo-SCT) with low-dose anti-human thymocyte immunoglobulin (ATG), tacrolimus, methotrexate and prednisolone (PSL) in 14 paediatric patients with high-risk childhood acute leukaemia. RESULTS: All patients achieved complete engraftment. The median time to reaching an absolute neutrophil count of more than 0.5 × 10(9) L(-1) was 14 days. Acute graft-vs-host disease (aGVHD) of grades II-IV and III-IV developed in 10 (71%) and 2 (14%) patients, respectively. Treatment-related mortality and relapse occurred in one (7%) patient and six (43%) patients, respectively. Eleven patients were alive and seven of them were disease-free with a median follow-up of 36 months (range: 30-159 months). The probability of event-free survival after 2 years was 50%. CONCLUSION: These findings indicate that T-cell-replete haplo-SCT, with low-dose ATG and PSL, provides sustained remission with an acceptable risk of GVHD in paediatric patients with advanced haematologic malignancies.


Assuntos
Leucemia/terapia , Transfusão de Linfócitos , Transplante de Células-Tronco , Linfócitos T/transplante , Doença Aguda , Adolescente , Aloenxertos , Criança , Pré-Escolar , Intervalo Livre de Doença , Feminino , Doença Enxerto-Hospedeiro/sangue , Doença Enxerto-Hospedeiro/mortalidade , Doença Enxerto-Hospedeiro/terapia , Humanos , Lactente , Leucemia/sangue , Leucemia/mortalidade , Contagem de Leucócitos , Masculino , Recidiva , Taxa de Sobrevida
4.
Clin Nephrol ; 74(5): 399-402, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20979950

RESUMO

Fibromuscular dysplasia (FMD) is a non-atheromatous, non-inflammatory, multifocal segmental angiopathy. FMD is the most common cause of pediatric renovascular hypertension. Aneurysmal formation of the main renal artery and distal branches is a rare complication of FMD in infancy. We report an 8-month-old boy with FMD presenting with shock caused by sudden renal hemorrhage that necessitated removal of one kidney. A diagnosis of renovascular hypertension resulting from intimal type FMD with aneurysmal formation was made on the basis of the presence of hypertension, elevation of PRA and aldosterone activity, pathological findings and the results of renal angiography. Our findings suggest that it is therefore necessary to consider FMD with aneurysmal formation as a possible cause of hypertension and renal hemorrhage in infants.


Assuntos
Aneurisma/etiologia , Displasia Fibromuscular/congênito , Hemorragia/etiologia , Hipertensão Renovascular/etiologia , Nefropatias/etiologia , Rim/irrigação sanguínea , Choque Hemorrágico/etiologia , Aldosterona/sangue , Aneurisma/diagnóstico por imagem , Aneurisma/terapia , Anti-Hipertensivos/uso terapêutico , Biomarcadores/sangue , Displasia Fibromuscular/diagnóstico por imagem , Displasia Fibromuscular/terapia , Hemorragia/diagnóstico por imagem , Hemorragia/terapia , Humanos , Hipertensão Renovascular/diagnóstico por imagem , Hipertensão Renovascular/terapia , Lactente , Rim/patologia , Rim/cirurgia , Nefropatias/diagnóstico por imagem , Nefropatias/terapia , Masculino , Nefrectomia , Radiografia , Renina/sangue , Choque Hemorrágico/diagnóstico por imagem , Choque Hemorrágico/terapia , Resultado do Tratamento , Regulação para Cima
5.
Arch Dis Child ; 91(6): 469-72, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16443616

RESUMO

AIMS: To evaluate the prognostic predictive values of cytochrome c, cytokines, and other laboratory measurements in serum collected during neurological onset in acute encephalopathy with multiple organ failure. METHODS: In addition to general laboratory examinations, the concentrations of cytochrome c (apoptosis marker) and cytokines (inflammatory markers) were measured in serum samples collected at the initial phase in 29 patients with acute encephalopathy. The obtained values were evaluated as predictors for the development of severe encephalopathy. RESULTS: Cytochrome c, tumour necrosis factor alpha (TNF-alpha), interleukin 6 (IL-6), soluble TNF-receptor 1 (sTNF-R1), and aspartate aminotransferase (AST) concentrations at the initial phase were high and correlated well with patient outcome. High concentrations of serum cytochrome c (>45 ng/ml), sTNF-R1 (>2000 pg/ml), AST (>58 IU/dl), IL-6 (>60 pg/ml), and TNF-alpha (>15 pg/ml) predicted an unfavourable prognosis (sequelae and death) at 93%, 79%, 82%, 77%, and 60%, respectively. The specificity of those markers was 100%, 89%, 83%, 100%, and 100%, respectively. CONCLUSIONS: Serum cytochrome c is the most sensitive and specific predictor for the development of severe encephalopathy at the initial phase. Results suggest that this marker might be used to guide decisions regarding the start of the initial treatment and further intensive care.


Assuntos
Citocromos c/sangue , Citocinas/sangue , Encefalite/sangue , Insuficiência de Múltiplos Órgãos/sangue , Doença Aguda , Área Sob a Curva , Aspartato Aminotransferases/sangue , Biomarcadores/sangue , Edema Encefálico/sangue , Criança , Pré-Escolar , Cuidados Críticos , Encefalite/mortalidade , Encefalite/terapia , Feminino , Humanos , Lactente , Interleucina-6/sangue , Masculino , Insuficiência de Múltiplos Órgãos/mortalidade , Insuficiência de Múltiplos Órgãos/terapia , Prognóstico , Curva ROC , Receptores do Fator de Necrose Tumoral/sangue , Sensibilidade e Especificidade , Fator de Necrose Tumoral alfa/análise
6.
J Dent Res ; 82(8): 581-4, 2003 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-12885839

RESUMO

Here we report that successful bone formation with a vascular flap inside a cylindrical mold was induced from fat tissue with the use of recombinant human bone morphogenetic protein-2 in rats. Fat tissue connected to blood vessels was prepared to fit into the mold and implanted intramuscularly into the hind leg in Wistar rats. RhBMP-2 (20 micro g) was applied in a collagen sheet previously placed on the inside surface of the mold. Bone formation was confirmed radiologically and morphologically at 2, 4, and 8 weeks after the surgery. In the control group without rhBMP-2 or the group with ligation of the blood vessels before the implantation, bone formation was not observed. Our success in bone formation having a definite size, shape, and blood supply may lead to a therapeutic approach to effective bone reconstitution. The present study is the first report on bone induction from fat tissue by rhBMP-2 in vivo.


Assuntos
Tecido Adiposo/irrigação sanguínea , Proteínas Morfogenéticas Ósseas/farmacologia , Osteogênese/efeitos dos fármacos , Retalhos Cirúrgicos/irrigação sanguínea , Fator de Crescimento Transformador beta/farmacologia , Adipócitos/patologia , Tecido Adiposo/transplante , Animais , Proteína Morfogenética Óssea 2 , Osso e Ossos/diagnóstico por imagem , Osso e Ossos/patologia , Colágeno , Humanos , Ligadura , Masculino , Membranas Artificiais , Músculo Esquelético/cirurgia , Osteoblastos/patologia , Radiografia , Ratos , Ratos Wistar , Proteínas Recombinantes , Coxa da Perna/cirurgia
7.
Vet Res Commun ; 26(5): 347-52, 2002 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-12212724

RESUMO

Changes in the activities of enzymes related to energy metabolism in the testicular tissues of dogs with seminoma were investigated. The testis was removed surgically from animals anaesthetized with halothane. Cytosolic and mitochondrial fractions were isolated and the total RNA was extracted from testicular homogenates. The activities of enzymes related to energy metabolism were measured and the mRNA of cytosolic malate dehydrogenase (MDH) was investigated by the reverse transcriptase-polymerase chain reaction (RT-PCR). The activities of the glycolytic enzymes glucose-6-phosphate dehydrogenase (G6PD) for the pentose phosphate pathway and malate dehydrogenase (MDH) for the malate-aspartate shuttle, and the expression of the mRNA of cytosolic MDH were significantly increased in the testicular tissues of dogs with seminoma. These enzymatic activities may be useful indicators with which to evaluate changes in the metabolic conditions in testicular tissues of dogs with seminoma.


Assuntos
Doenças do Cão/enzimologia , Metabolismo Energético , Seminoma/enzimologia , Testículo/enzimologia , Animais , Doenças do Cão/genética , Cães , Ativação Enzimática , Indução Enzimática , Enzimas/genética , Masculino , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Seminoma/genética
8.
Biochim Biophys Acta ; 1538(2-3): 162-71, 2001 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-11336787

RESUMO

We analyzed the tissue distribution of apelin mRNA in rats by a quantitative reverse transcription-polymerase chain reaction and that of immunoreactive apelin (ir-apelin) by an enzyme immunoassay (EIA) using a monoclonal antibody. The expression levels of apelin mRNA and ir-apelin seemed to be consistent among tissues: they were highly expressed in the lung and mammary gland. By the combination of gel filtration and EIA, we found that the molecular forms of apelin differ among respective tissues: apelin molecules with sizes close to apelin-36 (long forms) were major components in the lung, testis, and uterus, but both long and short (whose sizes were close to [

Assuntos
Proteínas de Transporte/análise , Receptores Acoplados a Proteínas G , Sequência de Aminoácidos , Animais , Apelina , Receptores de Apelina , Proteínas de Transporte/síntese química , Proteínas de Transporte/metabolismo , Cromatografia em Gel , Feminino , Técnicas Imunoenzimáticas , Peptídeos e Proteínas de Sinalização Intercelular , Pulmão/metabolismo , Masculino , Glândulas Mamárias Animais/metabolismo , Dados de Sequência Molecular , Peso Molecular , RNA Mensageiro/análise , Ratos , Ratos Wistar , Receptores de Dopamina D2 , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Testículo/metabolismo , Útero/metabolismo
9.
Endocrine ; 12(3): 215-21, 2000 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10963040

RESUMO

We validated the effect of prolactin-releasing peptide (PrRP) on prolactin (PRL) secretion from rat anterior pituitary cells in in vitro culture. We found that culture conditions considerably influenced the response of the anterior pituitary cells to PrRP. Longer culture term (4 d) was required to obtain better responses of the anterior pituitary cells to PrRP in comparison to thyrotropin-releasing hormone (TRH). Under the culture conditions employed here, PrRP was comparable to TRH in the potency promoting PRL secretion, and the action of PrRP was very specific for PRL secretion. The susceptibility of the anterior pituitary cells to PrRP varied in female rats depending on the process of reproduction: the cells prepared from lactating rats were the most sensitive to PrRP compared with those from random-cycle and pregnant rats. Because the expression levels of PrRP receptor mRNA in the pituitary varied during the reproductive process, we speculated that the susceptibility of the anterior pituitary cells would reflect cellular changes including the expression level of PrRP receptors. In addition, treatment with estrogen in vivo enhanced the susceptibility of the cultured anterior pituitary cells in male rats. Our results indicate that the susceptibility of the rat anterior pituitary cells to PrRP is regulated by physiological mechanisms.


Assuntos
Hormônios Hipotalâmicos/farmacologia , Neuropeptídeos/farmacologia , Adeno-Hipófise/efeitos dos fármacos , Prolactina/metabolismo , Animais , Células Cultivadas , Hormônio Liberador da Corticotropina/farmacologia , Feminino , Expressão Gênica , Hormônio Liberador de Gonadotropina/farmacologia , Hormônio Liberador de Hormônio do Crescimento/farmacologia , Cinética , Lactação , Masculino , Adeno-Hipófise/química , Adeno-Hipófise/metabolismo , Gravidez , Hormônio Liberador de Prolactina , RNA Mensageiro/análise , Ratos , Ratos Endogâmicos F344 , Receptores de Neuropeptídeos/genética , Receptores de Neuropeptídeos/fisiologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Hormônio Liberador de Tireotropina/farmacologia , Fatores de Tempo
10.
Brain Dev ; 21(8): 544-7, 1999 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-10598056

RESUMO

In tuberous sclerosis (TS), brain CT reveals subependymal nodules, cortical tubers and white matter lesions. This study is a retrospective analysis of the relationship between the variations over time in the number of subependymal nodules and the clinical course in cases of tuberous sclerosis. Twenty-four children with tuberous sclerosis, who attended the National Children's Hospital as outpatients, were followed by means of brain CT examinations for 7 years and 1 month on average. Cranial MRI was also performed in 22 cases. Brain CT disclosed subependymal nodules already in early infancy. In almost all cases, the number of subependymal nodules gradually increased with age, especially around the frontal horn of the lateral ventricle. The increase stopped at around age 10. The cases with five or more subependymal nodules at the initial or subsequent CT examination ( 17 patients; Group A) exhibited a significantly greater number of cortical tubers than those with less than five (five patients; Group B) and had white matter lesions unlike Group B. In addition, the number of cases with either infantile spasms or mental retardation was significantly higher in Group A than Group B (P < 0.005). In conclusion, the number of ventricular subependymal nodules may allow prediction of the severity of the cerebral dysfunction in TS. Our results suggest that its variation may reflect the degree of the embryologic disorder when neuronal cells grow in the early gestational period.


Assuntos
Neoplasias do Ventrículo Cerebral/fisiopatologia , Epêndima/fisiopatologia , Esclerose Tuberosa/fisiopatologia , Adolescente , Fatores Etários , Criança , Pré-Escolar , Progressão da Doença , Feminino , Humanos , Lactente , Masculino , Prognóstico
11.
Biochim Biophys Acta ; 1452(1): 25-35, 1999 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-10525157

RESUMO

By using a strategy that we have developed to search for the ligands of orphan seven-transmembrane-domain receptors [S. Hinuma et al., Nature 393 (1998) 272-276], we have recently identified a natural ligand, apelin, for the orphan 7TMR, APJ [K. Tatemoto et al., Biochem. Biophys. Res. Commun. 251 (1998) 471-476]. In this paper, we isolated rat and mouse apelin cDNAs, and analyzed the tissue distribution of apelin mRNA in rats. Although apelin mRNA was widely detected in a variety of tissues, the highest expression of apelin mRNA was detected in the mammary gland of pregnant rats. In the mammary gland, biologically active apelin and its mRNA considerably increased during pregnancy and lactation, and reached a maximal level around parturition. Moreover, a large amount of apelin (14-93 pmol/ml) was found to be secreted in the bovine colostrum, and it was still detectable even in commercial bovine milk. Since apelin partially suppressed cytokine production by mouse spleen cells in response to T cell receptor/CD3 cross-linking, the oral intake of apelin in the colostrum and milk might modulate immune responses in neonates.


Assuntos
Proteínas de Transporte/metabolismo , Colostro/metabolismo , Receptores Acoplados a Proteínas G , Adipocinas , Sequência de Aminoácidos , Animais , Apelina , Receptores de Apelina , Células CHO , Proteínas de Transporte/síntese química , Proteínas de Transporte/genética , Bovinos , Colforsina , Cricetinae , AMP Cíclico/metabolismo , DNA Complementar/isolamento & purificação , Feminino , Peptídeos e Proteínas de Sinalização Intercelular , Lactação/metabolismo , Ligantes , Masculino , Glândulas Mamárias Animais/metabolismo , Camundongos , Leite/química , Dados de Sequência Molecular , Gravidez/metabolismo , RNA Mensageiro/análise , Ratos , Ratos Wistar , Receptores de Dopamina D2/química , Receptores de Dopamina D2/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa
12.
Nature ; 393(6682): 272-6, 1998 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-9607765

RESUMO

Hypothalamic peptide hormones regulate the secretion of most of the anterior pituitary hormones, that is, growth hormone, follicle-stimulating hormone, luteinizing hormone, thyroid-stimulating hormone and adrenocorticotropin. These peptides do not regulate the secretion of prolactin, at least in a specific manner, however. The peptides act through specific receptors, which are referred to as seven-transmembrane-domain receptors or G-protein-coupled receptors. Although prolactin is important in pregnancy and lactation in mammals, and is involved in the development of the mammary glands and the promotion of milk synthesis, a specific prolactin-releasing hormone has remained unknown. Here we identify a potent candidate for such a hormone. We first proposed that there may still be unknown peptide hormone factors that control pituitary function through seven-transmembrane-domain receptors. We isolated the complementary DNA encoding an 'orphan' receptor (that is, one for which the ligand is unknown). This receptor, hGR3, is specifically expressed in the human pituitary. We then searched for the hGR3 ligand in the hypothalamus and identified a new peptide, which shares no sequence similarity with known peptides and proteins, as an endogenous ligand. We show that this ligand is a potent prolactin-releasing factor for rat anterior pituitary cells; we have therefore named this peptide prolactin-releasing peptide.


Assuntos
Hormônios Hipotalâmicos/fisiologia , Neuropeptídeos/fisiologia , Prolactina/metabolismo , Receptores Acoplados a Proteínas G , Sequência de Aminoácidos , Animais , Ácido Araquidônico/metabolismo , Células CHO , Bovinos , Cricetinae , Feminino , Humanos , Hormônios Hipotalâmicos/genética , Hormônios Hipotalâmicos/isolamento & purificação , Lactação , Ligantes , Dados de Sequência Molecular , Neuropeptídeos/genética , Neuropeptídeos/isolamento & purificação , Adeno-Hipófise/metabolismo , Hormônio Liberador de Prolactina , Precursores de Proteínas/genética , Precursores de Proteínas/isolamento & purificação , Ratos , Ratos Endogâmicos F344 , Receptores de Superfície Celular/metabolismo , Homologia de Sequência de Aminoácidos , Transdução de Sinais , Células Tumorais Cultivadas
13.
Bone Marrow Transplant ; 19(1): 49-53, 1997 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-9012931

RESUMO

From 1992 to 1995, 105 patients received PBSCT in our hospitals and we observed no incidence of CMV-pneumonia. To clarify whether activation of CMV occurs in these patients shell vial cultures, CMV antigenemia and PCR (DNA-PCR and RT-PCR) were used as detection methods for CMV. Bronchoalveolar lavage (BAL) samples, MNC and PMN samples from peripheral blood leukocytes, and urine samples were taken from 17 patients on day 35 after PBSCT. CMV was detected in one urine specimen but not detected in any of the BAL, MNC or PMN specimens by shell vial culture. CMV antigenemia provided no positive data. Nine of the 74 samples taken from the 17 patients proved positive by DNA-PCR, but all CMV-mRNA results were negative by RT-PCR. We performed CMV antigenemia and PCR on MNC and PMN specimens from six patients every 1 to 2 weeks after transplantation to determine whether and when CMV was activated. Two patients tested positive transiently by DNA-PCR but negative throughout by both antigenemia and RT-PCR. These results suggest that the risk of CMV infection is low because the incidence of CMV activation in patients receiving PBSCT is low.


Assuntos
Infecções por Citomegalovirus/etiologia , Citomegalovirus/isolamento & purificação , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Pneumonia Viral/etiologia , Adolescente , Antígenos Virais/análise , Criança , Pré-Escolar , Citomegalovirus/imunologia , Feminino , Humanos , Masculino , Pneumonia Viral/virologia , Reação em Cadeia da Polimerase , Estudos Prospectivos , Risco , Transplante Homólogo
14.
Biochem Pharmacol ; 52(8): 1279-85, 1996 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-8937436

RESUMO

The cytotoxic properties of 1-(2-deoxy-2-methylene-beta-D-erythro-pentofuranosyl)cytosine (DMDC) were compared with those of 1-beta-D-arabinofuranosylcytosine (ara-C), using SK-MEL-28(P-36) human melanoma cells. DMDC and ara-C were most cytotoxic to cells in the S phase of the cell cycle. Cell cycle progression in S phase was blocked by both compounds. Treatment with DMDC (1 microgram/mL) or ara-C (1 and 30 micrograms/mL) did not increase cytotoxicity against asynchronous cells when the exposure time was prolonged from 1 to 6 hr, but did increase cytotoxicity thereafter. These findings suggest that cells in S phase are rapidly killed by the treatment but are temporarily prevented or delayed entry into the drug-sensitive S phase. On the other hand, DMDC treatment at a higher concentration (30 micrograms/mL) increased cytotoxicity in a time-dependent manner. Intracellular DMDC 5'-triphosphate (DMDCTP) increased in proportion to exogenous DMDC concentration, which was not saturated by treatment with a maximum concentration of the compound at 80 micrograms/mL. In contrast, intracellular ara-C 5'-triphosphate reached peak level when the cells were treated with ara-C at 8 micrograms/mL. The cytotoxicity of DMDC treatment for 4 hr increased relative to the intracellular DMDCTP accumulated during the period. These findings suggest that in cells treated with DMDC at a high concentration, an effective DMDCTP level is maintained for an extended period after washing out the compound from the medium. Consequently, the cells would be killed in the same way as in the case of extended exposures over 6 hr to DMDC at low concentration or to ara-C, in addition to acute S-phase-specific cytotoxicity.


Assuntos
Antineoplásicos/farmacologia , Morte Celular/efeitos dos fármacos , Desoxicitidina/análogos & derivados , Antineoplásicos/metabolismo , Ciclo Celular/efeitos dos fármacos , Citarabina/farmacologia , Desoxicitidina/metabolismo , Desoxicitidina/farmacologia , Nucleotídeos de Desoxicitosina/metabolismo , Humanos , Cinética , Fosforilação , Fase S/efeitos dos fármacos , Células Tumorais Cultivadas
15.
Biochim Biophys Acta ; 1219(2): 251-9, 1994 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-7918619

RESUMO

In this study, we isolated genomic DNA fragments coding for the human thyrotropin-releasing hormone (TRH) receptor. Analysis of the nucleotide sequence revealed that the human TRH receptor gene had an exon-intron structure comprising at least two exons. A polypeptide encoded by the gene consisted of 398 amino acid residues with putative seven transmembrane domains. It showed high homology as a whole amino acid sequence with the rat and mouse TRH receptors except for considerable variation in the C-terminal region. Chromosomal mapping study indicated that the human TRH receptor gene was assigned to chromosome 8. Chinese hamster ovary (CHO) cells transfected with a DNA fragment containing the coding regions of the human TRH receptor bound with [3H]TRH. This binding was inhibited by adding unlabeled TRH in a dose-dependent fashion. Scatchard analysis indicated that the transfected CHO cells expressed a single class of high affinity binding sites at a dissociation constant (Kd) of approximately 1 nM. These results demonstrated that the isolated gene encoded a specific TRH receptor with high affinity.


Assuntos
Receptores do Hormônio Liberador da Tireotropina/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , Células CHO , Cromossomos Humanos Par 8 , Clonagem Molecular , Cricetinae , Primers do DNA/química , DNA Complementar/genética , Genes , Humanos , Ligantes , Dados de Sequência Molecular , Receptores do Hormônio Liberador da Tireotropina/metabolismo , Mapeamento por Restrição , Hormônio Liberador de Tireotropina/metabolismo
16.
Eur J Biochem ; 223(1): 147-53, 1994 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-7913440

RESUMO

We investigated a regulatory mechanism for the production of pituitary adenylate-cyclase-activating polypeptide (PACAP) using the human neuroblastoma cell line, IMR-32. Although immunoreactive (ir-) PACAP38 was produced by these cells, it was not accumulated in the culture medium. To overcome this problem, we cultured the cells in the presence of a biotinylated monoclonal antibody to PACAP38 in order to trap ir-PACAP38 in the medium. Then, the trapped ir-PACAP38 was measured with a two-site enzyme immunoassay based on the biotin-avidin interaction. These studies showed that confluent IMR-32 cells constitutively secreted at least 130 pg/10(6) cells per day of ir-PACAP38. Treatment of the cells with 1 mM 1, N6-dibutyryladenosine 3',5'-monophosphate (Bt2cAMP) or 0.1 microM phorbol 12-myristate 13-acetate stimulated ir-PACAP38 production at almost twice the basal level in IMR-32 cells, and these two reagents additively stimulated ir-PACAP38 production. Northern blot analysis indicated that treatment of the cells with both Bt2cAMP and the phorbol ester increased the intensity of several mRNA bands that hybridized with a cDNA probe for human PACAP precursor. We also found that IMR-32 cells possessed high-affinity type-I PACAP receptors (Kd = 230 pM, binding sites: 8.6 x 10(4) sites/cell), which had a 1000-fold higher affinity for PACAP38 and PACAP27 than for vasoactive intestinal polypeptide. The treatment of IMR-32 cells with PACAP and vasoactive intestinal polypeptide increased intracellular cAMP levels, and also increased ir-PACAP production. Northern blot analysis revealed that PACAP at 10 nM markedly stimulated the expression of a 3.7-kb mRNA band that hybridized with PACAP precursor cDNA. These results indicate that IMR-32 cells produce ir-PACAP38, and that PACAP stimulates the synthesis of PACAP mRNA and peptides by increasing intracellular cAMP. Although it remains to be investigated whether PACAP secreted by IMR-32 cells really acts in an autocrine fashion, the present study provides a useful model for further studies of the biological role of PACAP in neuronal cells that produce PACAP and also respond to PACAP.


Assuntos
Bucladesina/farmacologia , Neuropeptídeos/biossíntese , Hipófise/metabolismo , Acetato de Tetradecanoilforbol/farmacologia , Humanos , Neuropeptídeos/farmacologia , Neurotransmissores/biossíntese , Neurotransmissores/farmacologia , Polipeptídeo Hipofisário Ativador de Adenilato Ciclase , Receptores de Polipeptídeo Hipofisário Ativador de Adenilato Ciclase , Receptores de Polipeptídeo Hipofisário Ativador de Adenilato Ciclase , Receptores do Hormônio Hipofisário/metabolismo , Células Tumorais Cultivadas , Peptídeo Intestinal Vasoativo/farmacologia
17.
Biochem Biophys Res Commun ; 196(3): 1511-21, 1993 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-7902709

RESUMO

A functional cDNA clone for a human pituitary adenylate cyclase activating polypeptide (PACAP) receptor was isolated from a human pituitary cDNA library. The cDNA encoded a polypeptide consisting of 525 amino acids with putative seven hydrophobic domains. Chinese hamster ovary (CHO)-K1 cells transfected with the cDNA specifically bound PACAP and mediated PACAP-triggered intracellular accumulation of cAMP, indicating that this cDNA encoded a functional human PACAP Type I receptor. This receptor was structurally related to the vasoactive intestinal peptide (VIP), secretin, calcitonin and parathyroid hormone receptors and is much more homologous to a rat PACAP receptor. Northern blot analysis revealed that PACAP receptor mRNAs were expressed mainly in the brain and widely distributed in the central nervous system.


Assuntos
Hipófise/metabolismo , Receptores do Hormônio Hipofisário/biossíntese , Sequência de Aminoácidos , Animais , Sequência de Bases , Northern Blotting , Southern Blotting , Células CHO , Membrana Celular/metabolismo , Clonagem Molecular , Cricetinae , AMP Cíclico/metabolismo , DNA Complementar/metabolismo , Expressão Gênica , Biblioteca Gênica , Humanos , Cinética , Dados de Sequência Molecular , Neuropeptídeos/metabolismo , Neurotransmissores/metabolismo , Sondas de Oligonucleotídeos , Polipeptídeo Hipofisário Ativador de Adenilato Ciclase , Conformação Proteica , Ratos , Receptores de Polipeptídeo Hipofisário Ativador de Adenilato Ciclase , Receptores de Polipeptídeo Hipofisário Ativador de Adenilato Ciclase , Receptores do Hormônio Hipofisário/genética , Receptores do Hormônio Hipofisário/metabolismo , Homologia de Sequência de Aminoácidos , Transfecção , Peptídeo Intestinal Vasoativo/farmacologia
18.
J Infect Dis ; 168(3): 641-6, 1993 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-8354905

RESUMO

Six nucleoside analogues, two sulfated polysaccharides, and four protease inhibitors were evaluated in vitro as inhibitors of influenza virus replication. Four guanosine analogues (mizoribine, ribavirin, pyrazofurin, and 5-ethynyl-1-beta-D-ribofuranosylimidazole-4-carboxamide), the sulfated polysaccharide dextran sulfate (molecular weight 500,000), and two protease inhibitors (camostat mesilate and nafamostat mesilate) were inhibitory to the replication of strains of influenza virus types A and B at concentrations down to 0.3 micrograms/mL. Of these seven compounds, ribavirin, camostat mesilate, and nafamostat mesilate were efficacious in both reducing the virus titer and increasing the survival rate of influenza virus-infected chick embryos. For camostat mesilate, the ED50 (required to improve the survival rate of influenza virus-infected chick embryos by 50%) was 0.80 micrograms/g, and its selectivity index, based on the ratio of the 50% toxic dose (required to reduce the viability of chick embryos by 50%) to ED50, was 280. Camostat mesilate deserves further exploration for its potential in the treatment of influenza virus infection.


Assuntos
Sulfato de Dextrana/farmacologia , Gabexato/análogos & derivados , Vírus da Influenza A/efeitos dos fármacos , Vírus da Influenza B/efeitos dos fármacos , Nucleosídeos/farmacologia , Inibidores de Proteases/farmacologia , Adenosina/análogos & derivados , Animais , Antivirais/farmacologia , Benzamidinas , Células Cultivadas , Embrião de Galinha , Relação Dose-Resposta a Droga , Ésteres , Guanidinas/farmacologia , Guanosina/análogos & derivados , Vírus da Influenza A/crescimento & desenvolvimento , Vírus da Influenza B/crescimento & desenvolvimento , Ribavirina/farmacologia , Replicação Viral/efeitos dos fármacos
19.
Biochem Biophys Res Commun ; 194(1): 133-43, 1993 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-7687425

RESUMO

Two types of cDNA encoding PACAP receptors were isolated from the rat brain cDNA library by homology screening with a cDNA probe for VIP receptor. Nucleotide sequence analysis indicated that these two types of receptor mRNA were generated by alternative splicing mechanisms. These two cloned cDNAs were introduced into CHO cells respectively. Resultant transformants showed specific binding to [125I]PACAP27 which was displaced by unlabeled PACAP27 but not by VIP. Thus, these receptors are two subtypes of Type I PACAP receptor (Type I-A and Type I-B). The amino acid sequences of rat PACAP receptors deduced by the cDNAs showed a remarkable similarity with rat receptors for VIP, secretin, glucagon, and GHRH. A 6.5 kb significant hybridizing signal of the PACAP receptor mRNA was detected in the rat brain, and slight signal was also detected in the lung and the liver.


Assuntos
Processamento Alternativo , Encéfalo/metabolismo , Expressão Gênica , Hipófise/metabolismo , RNA Mensageiro/biossíntese , Receptores de Superfície Celular/biossíntese , Receptores do Hormônio Hipofisário , Sequência de Aminoácidos , Animais , Sequência de Bases , Clonagem Molecular/métodos , DNA , Biblioteca Gênica , Masculino , Dados de Sequência Molecular , Especificidade de Órgãos , Poli A/genética , Poli A/isolamento & purificação , Estrutura Secundária de Proteína , RNA/genética , RNA/isolamento & purificação , RNA Mensageiro/metabolismo , Ratos , Receptores de Superfície Celular/genética , Receptores de Superfície Celular/metabolismo , Receptores dos Hormônios Gastrointestinais/genética , Receptores dos Hormônios Gastrointestinais/metabolismo , Receptores de Polipeptídeo Hipofisário Ativador de Adenilato Ciclase , Receptores de Polipeptídeo Hipofisário Ativador de Adenilato Ciclase , Receptores de Peptídeo Intestinal Vasoativo , Homologia de Sequência de Aminoácidos , Peptídeo Intestinal Vasoativo/metabolismo
20.
Mol Pharmacol ; 42(6): 1109-17, 1992 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-1282664

RESUMO

Various polyoxometalates proved inhibitory to the replication of a number of enveloped DNA and RNA viruses, i.e., herpesviruses (herpes simplex and cytomegalo), togaviruses (Sindbis), paramyxoviruses (respiratory syncytial), rhabdoviruses (vesicular stomatitis), arenaviruses (Junin and Tacaribe), and retroviruses [human immunodeficiency virus type 1 (HIV-1) and type 2 (HIV-2), simian immunodeficiency virus, and murine sarcoma virus]. The most potent compounds, i.e., JM1590 [K13[Ce(SiW11O39)2]. 26H2O] and JM2766 [K6[BGa(H2O)W11O39]. 15H2O], inhibited HIV-1 and simian immunodeficiency virus at concentrations as low as 0.008-0.8 microM. The polyoxometalates also inhibited giant cell formation in co-cultures of HIV-infected HUT-78 cells and uninfected MOLT-4 cells. Studies designed to unravel the mechanism of action of these compounds revealed that they inhibit the reverse transcriptase activity associated with HIV. The polyoxometalates also proved inhibitory to the binding of HIV-1 virions to the cells. From "time of addition" experiments, whereby the polyoxometalates were added at different times after virus infection, their mechanism of anti-HIV action could be attributed to inhibition of virus-cell binding. There was a good correlation (r = 0.84) between the inhibitory effects of the compounds on HIV-1-induced cytopathicity and their inhibitory effects on syncytium formation and a close correlation (r = 0.902) between their inhibitory effects on syncytium formation and their interaction with gp120, whereas there was no correlation between their anti-HIV-1 activity and their inhibitory effects on HIV-1 reverse transcriptase. In flow cytometric studies, the compounds did not interfere with the binding of OKT4A/Leu-3a monoclonal antibody to the CD4 receptor of uninfected cells, but they inhibited binding of anti-gp120 monoclonal antibody to HIV-1-infected cells. Thus, the binding of the polyoxometalates to the viral envelope glycoprotein gp120 is responsible for their anti-HIV activity.


Assuntos
Antivirais/farmacologia , HIV-1/efeitos dos fármacos , HIV-2/efeitos dos fármacos , Compostos Organometálicos/farmacologia , Adesão Celular/efeitos dos fármacos , Células Cultivadas , Vírus de DNA/efeitos dos fármacos , Imunofluorescência , Células Gigantes/efeitos dos fármacos , Transcriptase Reversa do HIV , HIV-1/enzimologia , HIV-1/fisiologia , HIV-2/fisiologia , Vírus de RNA/efeitos dos fármacos , DNA Polimerase Dirigida por RNA/metabolismo , Inibidores da Transcriptase Reversa , Tungstênio , Replicação Viral/efeitos dos fármacos
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