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1.
BJS Open ; 4(2): 241-251, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32012492

RESUMO

BACKGROUND: Hepatocellular carcinoma (HCC) with tumour thrombus (TT) in the inferior vena cava (IVC) or right atrium (RA) is a rare advanced disease state with a poor prognosis. The aim of this study was to examine survival after surgical resection. METHODS: Patients with HCC and TT of either the IVC or RA, who underwent liver resection between February 1997 and July 2017, were included. Their short- and long-term outcomes and surgical details were analysed retrospectively. RESULTS: Thirty-seven patients were included; 16 patients had TT in the IVC below the diaphragm, eight had TT in the IVC above the diaphragm, and 13 had TT entering the RA. Twelve patients had advanced portal vein TT (portal vein invasion (Vp) greater than Vp3 and Vp4), ten had bilobar disease, and 12 had extrahepatic disease. There were no in-hospital deaths, although two patients died within 90 days. Median survival did not differ between patients who had resection with curative intent (18·7 months) and those with residual tumour in the lung only (20·7 months), but survival was poor for patients with residual tumour in the liver (8·3 months). CONCLUSION: Liver resection with thrombectomy for advanced HCC with TT in the IVC or RA is safe and feasible, leading to moderate survival.


ANTECEDENTES: El carcinoma hepatocelular con trombo tumoral (TT) en la vena cava inferior (inferior vena cava, IVC) o en la aurícula derecha (right atrium, RA) es un estado avanzado de la enfermedad raro, con un pronóstico desfavorable. En este estudio analizamos la supervivencia después de la resección quirúrgica. MÉTODOS: Se incluyeron pacientes con carcinoma hepatocelular con TT en la IVC o en la RA, que se sometieron a resección hepática entre febrero de 1997 y julio de 2017. Los resultados a corto y a largo plazo de estos pacientes y los detalles quirúrgicos se analizaron retrospectivamente. RESULTADOS: Se incluyeron 37 pacientes. Entre estos pacientes, se identificaron 16 pacientes con TT en la IVC infradiafragmática, 8 pacientes con TT en la IVC supradiafragmática y 13 pacientes con TT entrando en la AR. Doce pacientes asociaron TT avanzado en la vena porta más allá de vp 3 y 4, 10 pacientes tenían enfermedad bilobar y 12 pacientes tenían enfermedad extrahepática. A pesar de que la tasa de mortalidad hospitalaria fue cero, dos pacientes fallecieron a los 90 días. Aunque la mediana del tiempo de supervivencia no fue diferente entre el grupo al que se le realizó resección con intención curativa (18,7 meses) y aquellos con tumor residual solo en el pulmón (20,7 meses), la supervivencia fue extremadamente pobre para los pacientes con tumor residual en el hígado (8,3 meses). CONCLUSIÓN: La resección hepática con trombectomía para el carcinoma hepatocelular avanzado con trombo tumoral en la vena cava inferior o en la aurícula derecha es segura y factible, asociándose a una supervivencia moderada.


Assuntos
Carcinoma Hepatocelular/cirurgia , Átrios do Coração/cirurgia , Hepatectomia/métodos , Neoplasias Hepáticas/cirurgia , Trombectomia/métodos , Veia Cava Inferior/cirurgia , Idoso , Carcinoma Hepatocelular/mortalidade , Feminino , Humanos , Japão , Neoplasias Hepáticas/mortalidade , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Retrospectivos , Análise de Sobrevida
2.
Endocrinology ; 142(8): 3563-9, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11459804

RESUMO

It has been demonstrated that calcitonin-binding sites are present in a variety of tissue types, including in the pituitary gland. Interleukin-6 (IL-6) is also produced in the pituitary and it regulates the secretion of various hormones. In this study, we examined the expression of the calcitonin receptor and the mechanism of IL-6 production induced by calcitonin in the pituitary folliculo-stellate cell line (TtT/GF). The mRNA of calcitonin receptor subtype C1a, but not that of C1b, was detected by RT-PCR in TtT/GF cells and in the normal mouse pituitary. Calcitonin increased cAMP accumulation and IL-6 production in a concentration-dependent manner in TtT/GF cells. As calcitonin activates the PKA and PKC pathways, we investigated the contributions of PKA and PKC to IL-6 production. IL-6 production was only slightly increased by either 8-bromo-cAMP (1 mM) or phorbol 12-myristate 13-acetate (100 nM) alone. However, IL-6 was synergistically induced in the presence of both 8-bromo-cAMP (1 mM) and phorbol 12myristate 13-acetate (100 nM). Furthermore, calcitonin-induced IL-6 production was completely suppressed by H-89 (PKA inhibitor) or GF109203X (PKC inhibitor), indicating that the activation of both PKA and PKC is necessary for calcitonin-induced IL-6 production. On the other hand, pertussis toxin (G(i)/G(o) signaling inhibitor) treatment achieved an approximately 9-fold increase in calcitonin-induced IL-6 production. These results show that calcitonin-stimulated IL-6 production is mediated via both PKA- and PKC-signaling pathways, whereas calcitonin also suppresses IL-6 production by activating G(i)/G(o) proteins in folliculo-stellate cells.


Assuntos
Calcitonina/farmacologia , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Interleucina-6/biossíntese , Hipófise/efeitos dos fármacos , Hipófise/metabolismo , Proteína Quinase C/metabolismo , Animais , Linhagem Celular , AMP Cíclico/metabolismo , Inibidores Enzimáticos/farmacologia , Proteínas de Ligação ao GTP/fisiologia , Interleucina-6/antagonistas & inibidores , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Hipófise/citologia , RNA Mensageiro/metabolismo , Receptores da Calcitonina/genética , Transdução de Sinais/efeitos dos fármacos
3.
J Cell Physiol ; 183(2): 221-7, 2000 May.
Artigo em Inglês | MEDLINE | ID: mdl-10737897

RESUMO

Although Src transformation of NIH3T3 mouse fibroblasts has been shown to be dependent on Ras function, the signaling mechanism whereby Src induces malignant transformation of human epithelial cells still remains unclear. In the present study, we analyzed the functional role of Ras, which acts downstream of Src in intracellular signaling, in the acquisition of fully neoplastic potentials by v-Src-transformed human gallbladder epithelial cells (HAG/src3-1) by infecting these cells with replication-defective adenovirus vector expressing dominant negative H-Ras (AdCARasY57). High efficiency of gene transduction was demonstrated with the adenovirus vector containing beta-gal gene insert (AdCALacZ). On infection with AdCARasY57, the activity of mitogen-activated protein (MAP) kinase, a major downstream event triggered by Ras, was markedly inhibited over 7 days, indicating that the inhibition of Ras function by AdCARasY57 remains active during this period. AdCARasY57 did not inhibit the monolayer growth of HAG-1 cells transfected with activated H-ras, but inhibited the HAG/src3-1 cells by 30%, as compared with cells infected with AdCALacZ as a control. This growth inhibition by AdCARasY57 was strengthened nearly twofold on surfaces coated with an antiadhesive polymer (poly 2-hydroxyethylmethacrylate) that can quantitate anchorage-independent growth, and was much more pronounced up to 95% when assayed in soft agar. The HAG/src3-1 cells transfected with beta-gal gene produced tumors in nude mice within 4 weeks after implantation, whereas cells infected with AdCARasY57 failed to form tumors during this period. These findings show that Ras function is essential for v-Src-induced anchorage-independent growth in vitro as well as tumorigenesis in vivo, and that mitogenic activity driven by v-Src is not solely dependent on MAP kinase pathway. Because anchorage-independent growth correlates with tumor growth in vivo as well as metastatic potential, targeting Ras would be potentially useful for the treatment of human tumors with elevated Src tyrosine kinase activity.


Assuntos
Transformação Celular Neoplásica/genética , Genes ras , Genes src , Adenoviridae/genética , Animais , Linhagem Celular Transformada , Ativação Enzimática , Células Epiteliais/citologia , Células Epiteliais/metabolismo , Vesícula Biliar/citologia , Vesícula Biliar/metabolismo , Expressão Gênica , Vetores Genéticos , Humanos , Óperon Lac , Camundongos , Camundongos Nus , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Mutação , Neoplasias Experimentais/genética , Neoplasias Experimentais/metabolismo , Neoplasias Experimentais/patologia , Transdução de Sinais
4.
Biochem Pharmacol ; 58(9): 1497-500, 1999 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-10513993

RESUMO

To elucidate the intracellular function and localization of the heterotrimeric G-protein beta3 subunit (Gbeta3) in the heart, we studied the effects of subtype-specific beta-adrenergic receptor (beta-AR) stimulation on Gbeta3 localization using isoform-specific antibodies. The amount of Gbeta3 in the cytosol dramatically decreased in hearts perfused with isoproterenol (ISO) alone or ISO with ICI 118551, a beta2-AR antagonist. Propranolol or CGP 20712A, a beta1-AR antagonist, blocked the ISO-induced decrease in the Gbeta3 content of the cytosol. In contrast, Gbeta3 content of the membrane fraction significantly increased in hearts perfused with ISO alone or ISO with ICI 118551. We conclude that stimulation of the beta1-AR induces isoform-specific translocation of Gbeta3 from the cytosol to the membrane fraction in rat hearts.


Assuntos
Proteínas de Ligação ao GTP/metabolismo , Miocárdio/metabolismo , Receptores Adrenérgicos beta 1/metabolismo , Animais , Transporte Biológico , Membrana Celular/metabolismo , Citosol/metabolismo , Técnicas In Vitro , Masculino , Perfusão , Ratos , Ratos Sprague-Dawley , Frações Subcelulares
5.
Int J Oncol ; 15(4): 687-92, 1999 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-10493949

RESUMO

PLK (polo-like kinase), which belongs to a family of serine/threonine kinases and represents the human counterpart of structurally related protein kinases, polo of Drosophila melanogaster and CDC5 of Saccharomyces cerevisiae, may be implicated in spindle formation and chromosome segregation during mitosis. There are, however, few reports on the significance of PLK gene expression in human carcinomas. In order to evaluate its clinical significance, we examined the expression of the PLK mRNA in 49 esophageal and 75 gastric carcinomas, using reverse transcription-polymerase chain reaction analysis. In esophageal carcinomas, PLK overexpression was detected in 47 carcinomas (97%) when compared to the corresponding normal tissues. It is noteworthy that the patients with high-grade PLK overexpression represented a significantly poorer prognosis group than those with low-grade PLK overexpression (3-year survival rate: 54.9% vs 24.8%, p<0.05). A multivariate analysis demonstrated that the PLK mRNA expression status was an independent prognostic factor for patients with esophageal carcinoma. On the other hand, 55 gastric carcinomas (73%) were revealed to overexpress PLK mRNA, but the expression status showed no correlation with prognosis. This study demonstrated that the PLK overexpression was frequently observed in esophageal and gastric carcinomas, and appeared to be an independent prognostic factor for patients with esophageal carcinoma.


Assuntos
Neoplasias Esofágicas/metabolismo , Proteínas Quinases/biossíntese , Neoplasias Gástricas/metabolismo , Adenocarcinoma/diagnóstico , Adenocarcinoma/metabolismo , Carcinoma Basocelular/diagnóstico , Carcinoma Basocelular/metabolismo , Carcinoma de Células Pequenas/diagnóstico , Carcinoma de Células Pequenas/metabolismo , Carcinoma de Células Escamosas/diagnóstico , Carcinoma de Células Escamosas/metabolismo , Carcinossarcoma/diagnóstico , Carcinossarcoma/metabolismo , Proteínas de Ciclo Celular , Neoplasias Esofágicas/diagnóstico , Humanos , Mucosa/metabolismo , Análise Multivariada , Prognóstico , Proteínas Serina-Treonina Quinases , Proteínas Proto-Oncogênicas , RNA Mensageiro/biossíntese , Neoplasias Gástricas/diagnóstico , Taxa de Sobrevida , Quinase 1 Polo-Like
6.
Biochem Biophys Res Commun ; 261(3): 833-7, 1999 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-10441511

RESUMO

In a human eosinophilic leukemia cell line, EoL-1, cell proliferation was suppressed by 2-day treatment with troglitazone. EoL-1 cells treated with troglitazone were arrested and maintained in the G0/G1 phase in the cell cycle. This suppression correlated with the up-regulation of mRNA for p21WAF1/CIP1 cyclin-dependent kinase (Cdk) inhibitor. The inhibitory effects of troglitazone on cell proliferation and expression of p21 mRNA were observed in a human myelomonocytic cell line, U937, and a human myelomonoblastic cell line, KPB-M15. In addition, in EoL-1 cells, p21 protein was induced by troglitazone treatment and the induction was inhibited by protein synthesis inhibitor, cycloheximide. These data suggest that troglitazone inhibits cell proliferation in myeloid leukemia cell lines at least in part by induction of p21 Cdk inhibitor.


Assuntos
Antineoplásicos/farmacologia , Divisão Celular/efeitos dos fármacos , Cromanos/farmacologia , Ciclinas/biossíntese , Inibidores Enzimáticos , Leucemia Mieloide/patologia , Tiazóis/farmacologia , Tiazolidinedionas , Ciclo Celular , Inibidor de Quinase Dependente de Ciclina p21 , Ciclinas/genética , DNA/análise , Citometria de Fluxo , Expressão Gênica/efeitos dos fármacos , Humanos , Síndrome Hipereosinofílica/metabolismo , Síndrome Hipereosinofílica/patologia , Leucemia Mieloide/metabolismo , Leucemia Mielomonocítica Aguda/metabolismo , Leucemia Mielomonocítica Aguda/patologia , Leucemia Mielomonocítica Crônica/metabolismo , Leucemia Mielomonocítica Crônica/patologia , RNA Mensageiro/biossíntese , Troglitazona , Células Tumorais Cultivadas
7.
Brain Res ; 823(1-2): 161-8, 1999 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-10095022

RESUMO

The mechanisms involved in pheromone-induced responses in the vomeronasal neurons, especially in mammals, are still unclear. In the present study, we examined the effects of rat urine samples containing various types of pheromones regulating gonadal functions on the accumulation of cAMP and inositol 1,4,5-trisphosphate (IP3) in a vomeronasal membrane preparation from the female Wistar rat. Stimulation of the preparation with forskolin induced cAMP accumulation, but stimulation with urine samples excreted from the male Wistar rat, the female Wistar rat, and the male Donryu rat did not change cAMP levels. These results were consistent with the electrophysiological results showing that dialysis of a high concentration of cAMP into the vomeronasal neuron does not induce currents. Stimulation with the three urine samples induced the accumulation of IP3 in the membrane preparation. These results are consistent with previous electrophysiological results [K. Inamura, M. Kashiwayanagi, K. Kurihara, Inositol-1,4,5-trisphosphate induces responses in receptor neurons in rat vomeronasal sensory slices, Chem. Senses 22 (1997) 93-103; K. Inamura, M. Kashiwayanagi, K. Kurihara, Blockage of urinary responses by inhibitors for IP3-mediated pathway in rat vomeronasal sensory neurons, Neurosci. Lett. 233 (1997) 129-132]. After the treatment with Pertussis toxin (PTX), the male Wistar urine did not induce IP3 accumulation significantly. Application of the male Wistar urine decreased ADP-ribosylation of Gi with PTX, while that of the male Donryu urine decreased ADP-ribosylation of Go. Thus, the present results support a mechanism by which the responses of the rat vomeronasal neurons to urinary pheromones are mediated by IP3, Gi and/or Go.


Assuntos
Inositol 1,4,5-Trifosfato/metabolismo , Mucosa Nasal/metabolismo , Septo Nasal/metabolismo , Feromônios/fisiologia , Feromônios/urina , Caracteres Sexuais , Animais , Colforsina/farmacologia , AMP Cíclico/metabolismo , Feminino , Técnicas In Vitro , Inositol 1,4,5-Trifosfato/antagonistas & inibidores , Masculino , Mucosa Nasal/inervação , Septo Nasal/inervação , Neurônios/fisiologia , Toxina Pertussis , Ratos , Ratos Endogâmicos , Ratos Wistar , Fatores de Virulência de Bordetella/farmacologia
8.
Eur J Biochem ; 259(3): 801-8, 1999 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10092867

RESUMO

We have previously reported that pertussis toxin (PTX)-sensitive GTP binding protein (G-protein) and phosphatidylinositol 3-kinase (PI 3-K) are involved in adipocyte differentiation of 3T3-L1 cells induced by insulin/dexamethasone/methylisobutyl xanthine. The aim of this study was to examine the effect of PTX on the tyrosine kinase cascade stimulated by insulin acting through insulin-like growth factor-I (IGF-I) receptors in undifferentiated 3T3-L1 cells. A high level of mitogen-activated protein kinase (MAPK) activation was sustained for up to 4 h after insulin treatment, and mobility shifted and tyrosine phosphorylated MAPK was also detected. MAPK kinase activity measured by the incorporation of 32P into kinase-negative recombinant MAPK was enhanced by insulin treatment. We previously discovered that insulin activates Ras and that this is mediated by wortmannin-sensitive PI 3-K. Tyrosine-phosphorylation of IRS-1 and Shc also occurred in response to insulin. Subsequently, we investigated the effects of PTX on the activation of these proteins by insulin. Interestingly, treating 3T3-L1 cells with PTX attenuates the activation by insulin of both the Ras-MAPK cascade and PI 3-K. In contrast, neither tyrosine-phosphorylation of IRS-1 and Shc nor the interaction between IRS-1 and PI 3-K is sensitive to PTX. However, activation of the Ras-MAPK cascade and tyrosine-phosphorylation of Shc by epidermal growth factor are insensitive to PTX. These results indicate that there is another pathway which regulates PI 3-K and Ras-MAPK, independent of the pathway mediated by IGF-I receptor kinase. These findings suggest that in 3T3-L1 fibroblasts, PTX-sensitive G-proteins cross-talk with the Ras-MAPK pathway via PI 3-K by insulin acting via IGF-I receptors.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal , Proteínas Adaptadoras de Transporte Vesicular , Proteínas Quinases Dependentes de Cálcio-Calmodulina/metabolismo , Proteínas de Ligação ao GTP/metabolismo , Insulina/farmacologia , Toxina Pertussis , Fosfatidilinositol 3-Quinases/metabolismo , Transdução de Sinais/fisiologia , Fatores de Virulência de Bordetella/farmacologia , Proteínas ras/metabolismo , Células 3T3 , Animais , Ativação Enzimática , Proteína Adaptadora GRB2 , Proteínas Substratos do Receptor de Insulina , Camundongos , Quinases de Proteína Quinase Ativadas por Mitógeno , Fosfatos de Fosfatidilinositol/metabolismo , Fosfoproteínas/metabolismo , Fosforilação , Proteínas Quinases/metabolismo , Proteínas/metabolismo , Proteínas Adaptadoras da Sinalização Shc , Transdução de Sinais/efeitos dos fármacos , Proteína 1 de Transformação que Contém Domínio 2 de Homologia de Src , Tirosina/metabolismo
9.
Biochem J ; 336 ( Pt 2): 491-500, 1998 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-9820828

RESUMO

We examined the mechanism of action of lysophosphatidylcholine (LPC), which is suggested to be involved in the pathogenesis of atherosclerosis and inflammatory disorders, in HL-60 leukaemia cells. Extracellular 1-palmitoyl LPC increased the intracellular Ca2+ concentration in association with production of inositol phosphate. These actions of LPC were markedly inhibited by treatment of the cells with pertussis toxin and U73122, a phospholipase C inhibitor. The lipid-induced stimulation of the phospholipase C/Ca2+ system was also attenuated in the dibutyryl cAMP-induced differentiated (neutrophil-like) cells, in which phospholipase C activation induced by NaF or formyl-Met-Leu-Phe was enhanced. In contrast with the stimulatory action of 1-palmitoyl LPC, 1-stearoyl LPC was inhibitory for the phospholipase C/Ca2+ system stimulated by NaF as well as by 1-palmitoyl LPC or other Ca2+-mobilizing agonists. In a cell-free system, only an inhibitory effect on phospholipase C activity was observed even by 1-palmitoyl LPC; 1-stearoyl LPC was more inhibitive than 1-palmitoyl LPC. Taken together, these results suggest that atherogenic and inflammatory LPC exerts both stimulatory and inhibitory actions on the phospholipase C/Ca2+ system depending on the species of fatty acid residue of the lipid; the stimulatory effect is possibly mediated through G-protein-coupled receptors; the inhibitory effect might be caused by dysfunction of the components involved in the enzyme system owing to the amphiphilic nature of the lipid. 1-Palmitoyl LPC prefers the former receptor stimulation at least in intact cells, but 1-stearoyl LPC preferentially exerts the latter inhibitory action.


Assuntos
Cálcio/metabolismo , Células HL-60/efeitos dos fármacos , Lisofosfatidilcolinas/química , Lisofosfatidilcolinas/farmacologia , Fosfolipases Tipo C/efeitos dos fármacos , Bucladesina/farmacologia , Diferenciação Celular/efeitos dos fármacos , Sistema Livre de Células , Ativação Enzimática/efeitos dos fármacos , Células HL-60/metabolismo , Humanos , Ácidos Oleicos/química , Ácidos Palmíticos/química , Toxina Pertussis , Ácidos Esteáricos/química , Relação Estrutura-Atividade , Fosfolipases Tipo C/antagonistas & inibidores , Fatores de Virulência de Bordetella/farmacologia
10.
Am J Gastroenterol ; 93(10): 1956-9, 1998 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-9772064

RESUMO

We herein report a case of hemophagocytic syndrome that developed in a 25-yr-old man with fulminant ulcerative colitis and presumed acute pancreatitis. Physical examination on admission showed a chronically ill, delirious patient with an upper abdominal mass. Peripheral blood showed progressive pancytopenia and bone marrow aspirate smears revealed hypocellular bone marrow with an increase of histiocytes showing prominent hemophagocytosis. Plain abdominal radiography revealed toxic megacolon. Both ultrasound and computed tomography showed the enlargement of the pancreas, thus indicating presumed acute pancreatitis. No apparent neoplasms or viral or bacterial infections, which are normally reported to be the cause of hemophagocytic syndrome, were detected. The patient was successfully treated with high doses of prednisolone and gamma-globulin.


Assuntos
Colite Ulcerativa/complicações , Histiocitose de Células não Langerhans/complicações , Pancreatite/complicações , Doença Aguda , Adulto , Anti-Inflamatórios/uso terapêutico , Anti-Inflamatórios não Esteroides/uso terapêutico , Colite Ulcerativa/terapia , Histiocitose de Células não Langerhans/terapia , Humanos , Imunização Passiva , Masculino , Prednisolona/uso terapêutico
11.
Jpn J Pharmacol ; 77(1): 41-51, 1998 May.
Artigo em Inglês | MEDLINE | ID: mdl-9639059

RESUMO

The metabolic activities of four types of beta3-adrenoceptor (AR) agonists, BRL35135A, BRL28410, ICI215001 and CL316243, were compared with those of other beta1- and beta2-AR agonists in rat white adipocytes. All the beta3-AR agonists caused cAMP formation, free fatty acid release and 2-deoxyglucose uptake; the maximum activity levels were similar except for ICI215001, which was lower. However, the magnitude of potency and selectivity of these agonists differed. The most potent and selective beta3-agonist was CL316243. Metabolic activities and Northern blotting showed that there were three beta-AR subtypes that were coupled to adenylyl cyclase and contributed to the induction of lipolysis and glucose uptake. The rank order of the amounts of beta-AR subtypes was beta3 >>beta1> beta2. However, the physiological functions of beta-AR subtypes were essentially similar in rat white adipocytes. On the other hand, cAMP accumulation and Northern blotting showed that human adipocytes predominantly contained beta2-AR, with far lower levels of beta1- and beta3-ARs. These findings suggested that the beta3-AR plays an important role in energy metabolism and thermogenesis in which cross talk exists between beta1- and beta3-ARs in rat adipocytes, while beta2-AR is the most important for the lipolysis regulation in human subcutaneous adipocytes.


Assuntos
Adipócitos/efeitos dos fármacos , Receptores Adrenérgicos beta/efeitos dos fármacos , Adenilil Ciclases/metabolismo , Adipócitos/enzimologia , Adipócitos/metabolismo , Agonistas Adrenérgicos beta/farmacologia , Animais , AMP Cíclico/biossíntese , Desoxiglucose/metabolismo , Cães , Ácidos Graxos não Esterificados/metabolismo , Humanos , Masculino , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ratos , Ratos Wistar , Receptores Adrenérgicos beta/genética , Receptores Adrenérgicos beta 3
12.
Chem Senses ; 23(2): 207-12, 1998 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-9589168

RESUMO

Mechanisms of the amazing ability of salmon to migrate a long distance from open water to natal streams for spawning are still unknown. Lacustrine sockeye salmon (Oncorhynchus nerka) in Lake Toya offers an excellent model system for studying the orientation mechanism in open water, because mature fish return to the natal area with a high degree of accuracy. First we examined the percentage of fish returning to the natal area after they were released 7 km south of the natal area. Forty percent of control male mature fish and 25% of the fish blinded by injection of a mixture of carbon toner and corn oil into the eyeball were captured in the natal area within 5 days. Forty-four percent of fish with brass rings (control) and 31% of fish with NdFe magnetic rings which interfere with the magnetic cue were captured in the natal area within 3 days. These experiments suggested that, although the number of blinded fish captured in the natal area was less than that of the controls, the difference was not statistically significant. In the fish captured in the natal area within 3 or 5 days, fish which found the natal area using their olfactory cue after random swimming for a long time and returned to that area may be included. Hence we tracked fish telemetrically using an ultrasonic tracking system, and found that mature males released at a long distance (3.6 or 6.8 km) from the natal area swam straight to the vicinity of the natal area. Interference of the magnetic cue by the attachment of a magnetic ring did not affect their direct return. Blockage of the visual cue caused them to move randomly. These data suggest that lacustrine sockeye salmon return straight to the vicinity of the natal area using their visual cue and finally reach the exact homing point using their olfactory cue.


Assuntos
Salmão/fisiologia , Comportamento Sexual Animal/fisiologia , Olfato , Visão Ocular , Animais , Masculino , Estimulação Física
13.
Biochem Biophys Res Commun ; 253(2): 253-6, 1998 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-9878524

RESUMO

We measured the mRNA expression of the recently identified putative sphingosine 1-phosphate (S1P) receptors, i.e., Edg-1, AGR16/H218, and Edg-3, in HL-60 leukemia cells. Of these putative receptors, Edg-3 mRNA was abundantly expressed in undifferentiated HL-60 cells. Further, its mRNA expression was markedly downregulated by inducers of cell differentiation such as dibutyryl cAMP, retinoic acid, and 1alpha, 25-dihydroxyvitamin D3. The reduction of mRNA expression was associated with the attenuation of an S1P-induced increase in cytoplasmic free Ca2+ concentration. Thus, Edg-3, whose mRNA expression is downregulated during cell differentiation, may be responsible for the S1P-induced Ca2+ response in HL-60 leukemia cells.


Assuntos
Sinalização do Cálcio , Proteínas de Ligação a DNA/genética , Regulação para Baixo/genética , Células HL-60/metabolismo , Proteínas I-kappa B , Lisofosfolipídeos , RNA Mensageiro/biossíntese , Receptores de Superfície Celular/fisiologia , Receptores Acoplados a Proteínas G , Esfingosina/análogos & derivados , Células 3T3 , Animais , Northern Blotting , Cálcio/metabolismo , Diferenciação Celular/genética , Proteínas de Ligação a DNA/antagonistas & inibidores , Proteínas de Ligação a DNA/biossíntese , Células HL-60/patologia , Humanos , Camundongos , Inibidor de NF-kappaB alfa , RNA Mensageiro/antagonistas & inibidores , Receptores de Lisofosfolipídeos , Esfingosina/metabolismo
14.
J Neuroimmunol ; 76(1-2): 139-44, 1997 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-9184643

RESUMO

In human glioblastoma A172 cells, interleukin-6 (IL-6) production was induced by interleukin-1 beta (IL-1 beta) and dibutyryl cyclic AMP. These cells have been shown to induce IL-6 production via a cAMP-protein kinase A system. Since calcitonin (CT) and calcitonin gene-related peptide (CGRP) are known to increase cAMP accumulation in murine and rat astrocytes, we examined whether these neuropeptides induced IL-6 production in A172 cells. Human CT and human CGRP increased IL-6 production and cAMP accumulation in a dose-dependent manner. A specific protein kinase A inhibitor, H-89, inhibited both CT- and CGRP-induced IL-6 production. CT and CGRP have been shown to cross-react with each other. To exclude the possibility of this cross-reactivity, we studied the additive effects of CT and CGRP and the inhibitory effects of specific inhibitors. When 100 nM CT was added, cAMP accumulation stimulated by 10 nM CGRP (the maximal dose) was increased. CGRP (8-37), a specific CGRP receptor inhibitor, inhibited cAMP accumulation and IL-6 production induced by CGRP, but did not inhibit these effects when they were induced by CT. Salmon CT (8-32), a specific inhibitor of the CT receptor, inhibited cAMP accumulation induced by CT, but did not inhibit the effect induced by CGRP. These results demonstrated that CT can induce IL-6 production via cAMP accumulation and the effects of CT are mediated via its own receptors.


Assuntos
Calcitonina/farmacologia , Proteínas Quinases Dependentes de AMP Cíclico/fisiologia , Glioblastoma/imunologia , Interleucina-6/biossíntese , Sulfonamidas , Peptídeo Relacionado com Gene de Calcitonina/farmacologia , AMP Cíclico/metabolismo , Humanos , Isoquinolinas/farmacologia , Células Tumorais Cultivadas
15.
Am J Surg Pathol ; 21(4): 417-23, 1997 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-9130988

RESUMO

To investigate epithelial cell proliferation and oncoprotein expression of the serrated adenoma, a term that has been used synonymously with mixed hyperplastic and adenomatous polyp, immunohistochemical staining using polyclonal antibodies against Ki-67 and p53, and a Bcl-2 monoclonal antibody, was performed and the results compared with those in hyperplastic polyps and tubular adenomas. A total of 20 serrated adenomas all characterized by a serrated glandular pattern, contained immature goblet cells, upper crypt zone mitotic figures, and a few nucleoli within the epithelial cells. Twenty hyperplastic polyps and 20 tubular adenomas (all with low-grade dysplasia) were examined, and lesions that contained separate areas of hyperplastic and adenomatous glands were excluded. The Ki-67-positive rate in the middle zone of the crypts in serrated adenomas was significantly higher than in hyperplastic polyps but lower than in tubular adenomas; a similar tendency was also noted for the upper zone. Both serrated adenomas and hyperplastic polyps demonstrated Bcl-2-positive reactivity that was essentially limited to the lower crypt zone, while in contrast, involvement in tubular adenomas often extended to the middle zone. No p53 overexpression was found in any category. These results suggest that serrated adenomas may be committed to independent growth.


Assuntos
Adenoma/química , Neoplasias do Colo/química , Pólipos do Colo/química , Antígeno Ki-67/biossíntese , Proteínas Proto-Oncogênicas c-bcl-2/biossíntese , Proteína Supressora de Tumor p53/biossíntese , Adenoma/patologia , Neoplasias do Colo/patologia , Pólipos do Colo/patologia , Humanos , Coloração e Rotulagem
16.
FEBS Lett ; 402(2-3): 246-50, 1997 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-9037204

RESUMO

Insulin increased 2-deoxyglucose (2-DG) uptake via the translocation of glucose transporter (GLUT) 4 to the plasma membrane fraction in rat adipocytes. The stimulatory actions of insulin were accompanied by both an increase in the immunoreactive p85 subunit of phosphatidylinositol (PI) 3-kinase in the plasma membrane fractions and PI 3-kinase activation by tyrosine phosphorylation of the p85 subunit. The beta3-adrenoceptor agonist CL316243 (CL) suppressed all the insulin actions in adenosine deaminase (ADA)-treated cells, but was without effect in non-ADA-treated cells. The inhibitory effects of CL on GLUT 4 translocation and PI 3-kinase activation were abolished by the addition of N6-phenylisopropyl adenosine. Cholera toxin treatment, which markedly increased intracellular cAMP levels, suppressed increases in the levels of GLUT 4 and PI 3-kinase in the plasma membrane fractions in response to insulin. In addition, dibutyryl (Bt2) cAMP also impaired the activation of PI 3-kinase by insulin. These results indicated that CL suppressed insulin-stimulated glucose transport under conditions where cAMP levels were markedly increased (approximately 12-fold). The inhibitory actions of PI 3-kinase activation by insulin were exerted even when cAMP, 8-bromo-cAMP, or Bt2 cAMP was added to immunoprecipitates of the p85 subunit of PI 3-kinase, after treating the cells with insulin. These results suggest that CL suppressed insulin-stimulated PI 3-kinase activity via a cAMP-dependent mechanism, at least in part, direct cAMP action in ADA-treated adipocytes, by which PI 3-kinase activation was inhibited, resulting in the decrease in GLUT 4 translocation and subsequent 2-DG uptake in response to insulin.


Assuntos
Adipócitos/metabolismo , Tecido Adiposo/metabolismo , Agonistas Adrenérgicos beta/farmacologia , Dioxóis/farmacologia , Hipoglicemiantes/farmacologia , Insulina/farmacologia , Proteínas Musculares , Fosfotransferases (Aceptor do Grupo Álcool)/metabolismo , Receptores Adrenérgicos beta/fisiologia , Adenosina Desaminase/farmacologia , Animais , Bucladesina/farmacologia , Células Cultivadas , Toxina da Cólera/farmacologia , AMP Cíclico/metabolismo , Epididimo , Transportador de Glucose Tipo 4 , Cinética , Masculino , Proteínas de Transporte de Monossacarídeos/metabolismo , Fenilisopropiladenosina/farmacologia , Fosfatidilinositol 3-Quinases , Fosfotransferases (Aceptor do Grupo Álcool)/antagonistas & inibidores , Ratos , Ratos Wistar , Receptores Adrenérgicos beta 3
17.
Biochem Biophys Res Commun ; 220(1): 98-101, 1996 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-8602865

RESUMO

Many vertebrates have two olfactory systems such as the main olfactory organ and the vomeronasal organ. To compare the transduction mechanism in both systems, we measured adenylyl cyclase activity in turtle vomeronasal and olfactory epithelium preparations. Whereas forskolin and GTP induced cAMP accumulation in vomeronasal preparations, common odorants, which induced cAMP accumulation in olfactory preparations and electrophysiological responses in vomeronasal organs, did not induce cAMP accumulation in vomeronasal preparations. The present results suggest that the cAMP-mediated transduction pathway in the vomeronasal organ is not involved in transduction for common odorants and probably plays a role in perception of specific chemosignals.


Assuntos
Adenilil Ciclases/metabolismo , Nariz/enzimologia , Tartarugas/metabolismo , Animais , Colforsina/farmacologia , AMP Cíclico/metabolismo , Epitélio/efeitos dos fármacos , Epitélio/enzimologia , Epitélio/inervação , Guanosina 5'-O-(3-Tiotrifosfato)/farmacologia , Guanosina Trifosfato/farmacologia , Técnicas In Vitro , Nariz/efeitos dos fármacos , Nariz/inervação , Odorantes , Receptores Odorantes/efeitos dos fármacos , Receptores Odorantes/metabolismo , Transdução de Sinais , Olfato/fisiologia
18.
J Affect Disord ; 37(1): 13-21, 1996 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-8682974

RESUMO

We examined 36 patients with major depression diagnosed by DSM-III-R to find and qualify disturbances in brain oxygenation and hemodynamics during a psychological task. A group of 36 age- and sex-matched healthy volunteers were monitored as controls. Multichannel near-IR spectrophotometry (NIRS) was used to observe real-time alterations in the oxygenation in corresponding areas of the hemispheres at the forehead during the mirror drawing task (MDT). Nearly half of the patients (12 of 24 males and 4 of 12 females) showed a 'nondominant hemisphere response pattern', which was never observed in normal volunteers during the MDT. The other half of the patients showed a 'bilateral response pattern'. There was no 'dominant hemisphere response pattern', the pattern observed in most normal males. When re-examined after recovery from depression, the response pattern of the two patients who had shown the 'nondominant hemisphere response pattern' during the course of the illness had changed to the 'bilateral response pattern'. The response pattern of the three patients with refractory depression who first showed the 'bilateral response pattern' changed to the 'nondominant response pattern' after several months. The nominally 'nondominant' hemisphere may become dominant during the course of depression.


Assuntos
Transtorno Depressivo/fisiopatologia , Dominância Cerebral/fisiologia , Adulto , Mapeamento Encefálico , Córtex Cerebral/irrigação sanguínea , Córtex Cerebral/fisiopatologia , Transtorno Depressivo/diagnóstico , Transtorno Depressivo/psicologia , Feminino , Humanos , Masculino , Testes Neuropsicológicos , Orientação/fisiologia , Consumo de Oxigênio/fisiologia , Resolução de Problemas/fisiologia , Desempenho Psicomotor/fisiologia , Fluxo Sanguíneo Regional/fisiologia , Espectrofotometria Infravermelho
19.
Neurochem Int ; 28(2): 161-8, 1996 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-8719704

RESUMO

We have investigated the response of adenylate cyclase to GTP and to dopamine (DA) in striatal membranes of rats treated for 3 weeks with chlorpromazine or haloperidol, and further measured the level of Gi (an inhibitory GTP-binding protein) or Go (a similar GTP-binding protein of unknown function) in 3 areas (cerebral cortex, striatum and hippocampus) utilizing pertussis toxin-catalyzed ADP ribosylation. In saline-treated control membranes, GTP exerted a biphasic effect on basal and DA-stimulated enzyme activity--peak levels of stimulation by DA plus GTP were observed at 1 microM GTP. Conversely, dopaminergic inhibitory effects at 10-100 microM GTP were completely attenuated in chlorpromazine or haloperidol-treated membranes. D2 inhibition of adenylate cyclase by the selective D2 agonist PPHT was also attenuated due to these neuroleptic treatments, while an increase in D2 receptor binding was observed. The pertussis toxin ADP-ribosylation of G-proteins (Gi/Go) did not differ significantly in any area. This indicates that long-term neuroleptic treatments increased D2 receptor binding, but attenuated D2 inhibition of adenylate cyclase, and exercised no influence on pertussis toxin ADP-ribosylation.


Assuntos
Adenosina Difosfato Ribose/metabolismo , Inibidores de Adenilil Ciclases , Antipsicóticos/farmacologia , Química Encefálica/efeitos dos fármacos , Agonistas de Dopamina/farmacologia , Receptores de Dopamina D2/agonistas , Toxina Adenilato Ciclase , Animais , Benzazepinas/metabolismo , Encéfalo/enzimologia , Clorpromazina/farmacologia , Antagonistas de Dopamina/metabolismo , Haloperidol/farmacologia , Masculino , Neostriado/efeitos dos fármacos , Neostriado/metabolismo , Toxina Pertussis , Ratos , Ratos Wistar , Espiperona/metabolismo , Fatores de Virulência de Bordetella/farmacologia
20.
Brain Res Cogn Brain Res ; 2(3): 215-9, 1995 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-7580403

RESUMO

The present paper demonstrates region-dependent variations in the oxygenation and hemodynamics of the brain hemispheres due to three different types of mental stimulation. The variations were observed with a four-channel optical imaging system using tissue-transparent near-infrared light and described changes from baseline of both the hemoglobin oxygenation state and blood volume during three kinds of psychological or mental tasks. During the mirror drawing task, a lateralized hemisphere response (the dominant hemisphere response pattern) was observed in 57% of 14 right handed volunteers in the frontal region (Brodmann's area 10), while in the temporal region (area 38), 80% showed the bilateral response pattern. A large majority of the subjects showed the bilateral response pattern in the frontal and temporal regions while calculating. A smaller majority showed this while looking at anatomical charts, though 30% did not show any response at all in the temporal region. This showed that there were region-dependent asymmetrical or symmetrical variations of the oxygen delivery-oxygen utilization relationship due to different types of mental stimuli.


Assuntos
Química Encefálica/fisiologia , Circulação Cerebrovascular/fisiologia , Processos Mentais/fisiologia , Consumo de Oxigênio/fisiologia , Adulto , Lateralidade Funcional/fisiologia , Hemoglobinometria , Humanos , Masculino , Espectrofotometria Infravermelho
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