Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 150
Filtrar
1.
Toxicol In Vitro ; 28(5): 961-7, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24727680

RESUMO

Uterine bacterial infection perturbs uterine and ovarian functions in postpartum dairy cows. Peptidoglycan (PGN) produced by gram-positive bacteria has been shown to disrupt the ovarian function in ewes. The aim of this study was to determine the effect of PGN on steroid production in bovine theca cells at different stages of follicular development. Bovine theca cells isolated from pre- and post-selection ovarian follicles (<8.5mm and >8.5mm in diameter, respectively) were cultured in vitro and challenged with PGN. Steroid production was evaluated by measuring progesterone (P4) and androstenedione (A4) concentration in culture media after 48 h or 96 h of culture. Bovine theca cells expressed PGN receptors including Toll-like receptor 2 and nucleotide-binding oligomerization domain 1 and 2. Treatment with PGN (1, 10, or 50 µg/ml) led to a decrease in P4 and A4 production by theca cells in both pre- and post-selection follicles. The mRNA expression of steroidogenic enzymes were decreased by PGN treatment. Moreover, A4 production was further suppressed when theca cells of post-selection follicles were simultaneously treated by PGN and lipopolysaccharide (0.1, 1, or 10 µg/ml). These findings indicate that bacterial toxins may act locally on ovarian steroidogenic cells and compromise follicular development in postpartum dairy cows.


Assuntos
Androstenodiona/antagonistas & inibidores , Toxinas Bacterianas/toxicidade , Peptidoglicano/toxicidade , Progesterona/antagonistas & inibidores , Células Tecais/efeitos dos fármacos , Androstenodiona/metabolismo , Animais , Bovinos , Células Cultivadas , Feminino , Lipopolissacarídeos/farmacologia , Proteína Adaptadora de Sinalização NOD1/genética , Proteína Adaptadora de Sinalização NOD2/genética , Fosfoproteínas/genética , Progesterona/metabolismo , RNA Mensageiro/metabolismo , Receptores do LH/genética , Staphylococcus aureus , Esteroide 17-alfa-Hidroxilase/genética , Células Tecais/metabolismo , Receptor 2 Toll-Like/genética
2.
Int J Gynecol Cancer ; 16(1): 409-15, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16445667

RESUMO

This study investigated the value of the in vitro histoculture drug response assay (HDRA) for predicting the efficacy of chemotherapy in patients with endometrial cancer. Specimens were obtained from 115 patients with endometrial cancer treated at Keio University Hospital between 1994 and 2002. Tumor fragments were cultured on collagen sponge gel with cisplatin for 7 days, and cell viability was assessed. The cutoff value of the 50% inhibitory concentration of cisplatin was set at 23 microg/mL. Sensitivity of stage III or IV disease to chemotherapy was investigated, and differences of 5-year progression-free survival between patients with sensitive and resistant tumors were evaluated by the Kaplan-Meier method. Tumors were evaluable in 93.0% of patients (107/115). Among 38 patients in stages III or IV, 23 received chemotherapy containing cisplatin. Seven sensitive tumors did not recur, while recurrence/progression occurred within 6 months in 8/16 patients with tumors showing low sensitivity. Among stages III and IV patients, there was a significant difference of 5-year progression-free survival (P < 0.05) between those with tumors showing high or low sensitivity. Accordingly, the HDRA may predict the efficacy of chemotherapy for endometrial cancer.


Assuntos
Cisplatino/farmacologia , Resistencia a Medicamentos Antineoplásicos , Ensaios de Seleção de Medicamentos Antitumorais , Neoplasias do Endométrio/tratamento farmacológico , Neoplasias do Endométrio/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Biópsia por Agulha , Cisplatino/administração & dosagem , Feminino , Humanos , Imuno-Histoquímica , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Valor Preditivo dos Testes , Probabilidade , Prognóstico , Estudos Retrospectivos , Estudos de Amostragem , Sensibilidade e Especificidade , Técnicas de Cultura de Tecidos , Resultado do Tratamento
3.
Int J Gynecol Cancer ; 15(3): 445-52, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-15882168

RESUMO

Despite cytoreductive surgery and chemotherapy, the prognosis of advanced ovarian cancer is still poor. Predicting the chemosensitivity of tumors might improve the outcome. Therefore, we investigated the clinical value of the histoculture drug response assay for ovarian cancer. Tumor specimens were cultured for 7 days on collagen gel sponge in medium containing cisplatin, and the 50% inhibitory concentration was determined by the 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyltetrazolium bromide assay. Then the in vitro sensitivity to cisplatin was compared with the clinical response and survival. Apoptosis of tumor cells was also investigated. Among 173 ovarian cancer patients, 164 were evaluable by the assay, and 29 patients had measurable lesions for which the clinical response could be determined. The 5-year survival rate was significantly higher in patients with chemosensitive tumors than in those with chemoresistant tumors when the cutoff value was set at a 50% inhibitory concentration of 25 microg/mL and the accuracy of the assay was 82.8% (24/29). As chemosensitivity to cisplatin became greater, the number of apoptotic cells also increased. This chemosensitivity assay may help predict the clinical response to cisplatin-based chemotherapy, thus improving the survival of ovarian cancer patients.


Assuntos
Antineoplásicos/farmacologia , Cisplatino/farmacologia , Neoplasias Ovarianas/tratamento farmacológico , Neoplasias Ovarianas/patologia , Adulto , Idoso , Apoptose , Sobrevivência Celular , Resistencia a Medicamentos Antineoplásicos , Ensaios de Seleção de Medicamentos Antitumorais , Feminino , Humanos , Pessoa de Meia-Idade , Prognóstico , Sensibilidade e Especificidade , Análise de Sobrevida , Células Tumorais Cultivadas
4.
Reprod Domest Anim ; 40(2): 184-9, 2005 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15819972

RESUMO

It has been reported that the posterior pituitary (PP) gland contains a potent, unknown prolactin (PRL)-releasing factor (PRF) in rats. PRFs are assumed to be produced in neurones located within the hypothalamus, and to be peptidergic in nature. However, little is known about PRFs in domestic animals. To characterize the PRF in the PP of domestic animals, the present study examined the PRL-releasing activity of an acidic extract from bovine PP (bPP) in vitro and in vivo in cattle. First, the PRL-releasing effect of bPP extract was compared with that of PRL-releasing peptide (PrRP), and thyrotropin-releasing hormone (TRH) from cultured bovine anterior pituitary cells. The extract significantly increased PRL concentrations in the culture medium, at doses of 0.002 and 0.02 eq./ml (one eq. is the PP extract from one animal), compared with the control (p < 0.05). PrRP failed to stimulate the release of PRL. TRH significantly increased PRL concentrations in the culture medium, at doses from 10(-9) to 10(-7) M, compared with the control (p < 0.05). The rate of increase in the PRL concentration, by 0.02 eq./ml bPP extract, was significantly greater than that in TRH (p < 0.05). Secondly, plasma PRL responses to the intravenous (i.v.) injection of bPP extract (0.5 eq./head), PrRP [3.59 mug/kg body weight (BW)], TRH (1 mug/kg BW), and a dopamine receptor antagonist (sulpiride, 0.1 mg/kg BW), were examined in calves. PrRP failed to stimulate PRL release; however, plasma PRL increased immediately following the injection of bPP extract, TRH and sulpiride. The PRL-releasing effect of i.v. injections of TRH and sulpiride was more potent than that of bPP extract. Finally, plasma PRL responses to the intra-hypothalamic injection of bPP extract were examined in calves. The intra-hypothalamic infusion (arcuate nucleus) of 0.0625 eq./head of bPP extract strongly stimulated PRL release in calves (p < 0.05). The present results show that PP contains a physiologically potent PRF in cattle.


Assuntos
Bovinos/fisiologia , Adeno-Hipófise/metabolismo , Neuro-Hipófise/metabolismo , Prolactina/metabolismo , Hormônio Liberador de Tireotropina/metabolismo , Extratos de Tecidos/farmacologia , Animais , Relação Dose-Resposta a Droga , Radioimunoensaio/veterinária , Sulpirida/metabolismo , Sulpirida/farmacologia , Tireotropina/metabolismo , Tireotropina/farmacologia , Hormônio Liberador de Tireotropina/farmacologia
5.
Domest Anim Endocrinol ; 24(3): 209-18, 2003 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-12642161

RESUMO

To clarify the direct effects of Ghrelin on growth hormone (GH) release from anterior pituitary (AP) cells in pigs, GH-releasing effects of human Ghrelin (hGhrelin) and rat Ghrelin (rGhrelin) on porcine AP cells were compared with GHRH in vitro. The AP cells were obtained from 6-month-old pigs and the cells (2 x 10(5) cells per well) were incubated for 2 h with the peptides after incubating in DMEM for 3 days. hGhrelin and rGhrelin significantly stimulated GH release from the cultured cells at doses of 10(-8) and 10(-7)M (P < 0.05). The rates of increase in GH at 10(-8) and 10(-7)M of hGhrelin were 82.7 and 131.9%, while those with rGhrelin were 43.9 and 79.5%, respectively. GHRH significantly stimulated GH release from the cells at a dose as low as 10(-11)M (P < 0.05), and the response to GHRH was greater than that induced by Ghrelins. In time-course experiments, GHRH continued to increase GH concentrations in media until 120 min after incubation; however, those in media treated with hGhrelin reached a plateau 60 min after incubation, and the maximal value was approximately one third that obtained with GHRH. When hGhrelin (10(-8)M) and GHRH (10(-8)M) were added together, additive effects of both peptides on the release of GH were observed (P < 0.05). Somatostatin (SS, 10(-7)M) significantly blunted GH release induced by hGhrelin (10(-8)M) and GHRH (10(-8)M) (P < 0.05). In the presence of SS, additive effects of hGhrelin and GHRH on the release of GH were observed (P < 0.05). These results show that Ghrelin directly stimulates GH release from anterior pituitary cells in pigs; however, the GH-releasing effect is weaker than that of GHRH in vitro. The present results also show that Ghrelin interacts with GHRH and SS to in the release of GH from porcine adenohypophysial cells.


Assuntos
Hormônio do Crescimento/metabolismo , Hormônios Peptídicos/farmacologia , Adeno-Hipófise/efeitos dos fármacos , Adeno-Hipófise/metabolismo , Suínos/fisiologia , Animais , Células Cultivadas , Feminino , Grelina , Hormônio Liberador de Hormônio do Crescimento/farmacologia , Cinética , Masculino , Somatostatina/farmacologia
6.
J Hepatobiliary Pancreat Surg ; 8(5): 479-84, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11702260

RESUMO

Resection of a pancreatic head tumor and partial resection of the liver for metastatic lesions were carried out simultaneously in a 72-year-old woman. The patient had a history of two previous operations, right nephrectomy for renal cell carcinoma (clear cell type), done 14 years previously, and an Autincloss procedure for cancer of the left breast (solid tubular carcinoma); (T1N0M0; stage I) done 7 years previously. At the current presentation, preoperative radiographic examination showed a hypervascular tumor in each of the pancreatic and hepatic lesions, but with different patterns. On the basis of histological findings in the two resected specimens, it was difficult to establish whether the hepatic tumor originated from the renal cell carcinoma or the breast cancer, but postoperative immunohistochemical studies for carcinoembryonic antigen (CEA), estrogen receptors, and gross cystic disease fluid protein (GCDFP)-15 showed that the pancreatic tumor had metastasized from the renal cell carcinoma, and the liver tumor from the breast cancer. The immunohistochemical investigation of different markers thus proved to be useful in making the final diagnosis of metastatic lesions from different and metachronous cancers.


Assuntos
Neoplasias da Mama/patologia , Carcinoma de Células Renais/patologia , Neoplasias Renais/patologia , Neoplasias Hepáticas/cirurgia , Neoplasias Pancreáticas/cirurgia , Idoso , Feminino , Humanos , Imuno-Histoquímica , Neoplasias Hepáticas/secundário , Neoplasias Pancreáticas/secundário
7.
Circulation ; 104(22): 2716-21, 2001 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-11723025

RESUMO

BACKGROUND: To investigate the effect of angiotensin (Ang) II type 1 receptor (AT(1)) blocker on vascular remodeling and explore the possibility of the involvement of Ang II type 2 receptor (AT(2)) stimulation in this process, we examined the effects of the selective AT(1) blocker valsartan on the vascular injury in wild-type (Agtr2+) and AT(2)-null (Agtr2-) mice. METHODS AND RESULTS: Neointima formation and the proliferation of vascular smooth muscle cells (VSMCs) induced by cuff placement on the femoral artery were greater in Agtr2- mice than those in Agtr2+ mice. Treatment of mice with valsartan at a dose of 1 mg. kg(-1). d(-1), which did not influence systolic blood pressure, significantly decreased neointima formation and the proliferation of VSMCs, whereas the valsartan was less effective in Agtr2- mice. Moreover, cuff placement increased the expression of monocyte chemoattractant protein-1 (MCP-1); inflammatory cytokines such as tumor necrosis factor (TNF)-alpha, interleukin (IL)-6, and IL-1beta; and infiltration of CD45-positive leukocytes and macrophages in the injured arteries and further enhanced them in Agtr2- mice, suggesting the antagonistic effects of AT(1) and AT(2) for vascular inflammation. Valsartan attenuated the expression of MCP-1, TNF-alpha, IL-6, IL-1beta, and infiltration of leukocytes and macrophages in the injured arteries; however, these effects of valsartan were less prominent in Agtr2- mice. CONCLUSIONS: These results suggest that the stimulation of the AT(2) receptor after AT(1) blockade is important in the improvement of the inflammatory vascular injury.


Assuntos
Antagonistas de Receptores de Angiotensina , Artéria Femoral/metabolismo , Inflamação/metabolismo , Receptores de Angiotensina/metabolismo , Tetrazóis/farmacologia , Valina/farmacologia , Angiotensina I/genética , Angiotensina I/metabolismo , Angiotensina II/genética , Angiotensina II/metabolismo , Animais , Anti-Hipertensivos/farmacologia , Pressão Sanguínea/efeitos dos fármacos , Divisão Celular/efeitos dos fármacos , Quimiocina CCL2/metabolismo , Artéria Femoral/efeitos dos fármacos , Artéria Femoral/patologia , Inflamação/tratamento farmacológico , Inflamação/patologia , Interleucina-1/metabolismo , Interleucina-6/metabolismo , Antígenos Comuns de Leucócito/metabolismo , Leucócitos/metabolismo , Leucócitos/patologia , Macrófagos/metabolismo , Macrófagos/patologia , Masculino , Camundongos , Camundongos Knockout , Músculo Liso Vascular/efeitos dos fármacos , Músculo Liso Vascular/metabolismo , Músculo Liso Vascular/patologia , Proteína Tirosina Fosfatase não Receptora Tipo 1 , RNA Mensageiro/metabolismo , Receptor Tipo 1 de Angiotensina , Receptor Tipo 2 de Angiotensina , Receptores de Angiotensina/deficiência , Receptores de Angiotensina/genética , Fator de Necrose Tumoral alfa/metabolismo , Túnica Íntima/efeitos dos fármacos , Túnica Íntima/metabolismo , Túnica Íntima/patologia , Valina/análogos & derivados , Valsartana
8.
J Pept Sci ; 7(9): 474-87, 2001 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11587186

RESUMO

An expressed peptide proved to be useful as a building block for the synthesis of a polypeptide via the thioester method. A partially protected peptide segment, for use as a C-terminal building block, could be prepared from a recombinant protein; its N-terminal amino acid residue was transaminated to an alpha-oxoacyl group, the side-chain amino groups were then protected with t-butoxycarbonyl (Boc) groups, and. finally, the alpha-oxoacyl group was removed. On the other hand, an O-phosphoserine-containing peptide thioester was synthesized via a solid-phase method using Boc chemistry. These building blocks were then condensed in the presence of silver ions and an active ester component. During the condensation, epimerization at the condensation site could be suppressed by the use of N,N-dimthylformamide (DMF) as a solvent. Using this strategy, a phosphorylated partial peptide of the p21Max protein, [Ser(PO3H2)2.11]-p21Max(1-101), was successfully synthesized.


Assuntos
Proteínas de Ligação a DNA/química , Biossíntese Peptídica , Peptídeos/química , Fatores de Transcrição , Fatores de Transcrição de Zíper de Leucina Básica , Cromatografia Líquida de Alta Pressão , Proteínas de Ligação a DNA/metabolismo , Dimetilformamida/farmacologia , Modelos Químicos , Fosforilação , Fosfosserina/química , Ligação Proteica , Estrutura Terciária de Proteína , Solventes/farmacologia , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Fatores de Tempo
9.
Hypertension ; 38(3): 367-72, 2001 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11566906

RESUMO

Angiotensin (Ang) II has 2 major receptor isoforms, Ang type 1 (AT(1)) and Ang type (AT(2)). AT(1) transphosphorylates epidermal growth factor receptor (EGFR) to activate extracellular signal-regulated kinase (ERK). Although AT(2) was shown to inactivate ERK, the action of AT(2) on EGFR activation remains undefined. Using AT(2)-overexpressing vascular smooth muscle cells from AT(2) transgenic mice, we studied these undefined actions of AT(2). Maximal ERK activity induced by Ang II was increased 1.9- and 2.2-fold by AT(2) inhibition, which was abolished by orthovanadate but not okadaic acid or pertussis toxin. AT(2) inhibited AT(1)-mediated EGFR tyrosine phosphorylation by 63%. The activity of SHP-1 tyrosine phosphatase was significantly upregulated 1 minute after AT(2) stimulation and association of SHP-1 with EGFR was increased, whereas AT(2) failed to tyrosine phosphorylate SHP-1. Stable overexpression of SHP-1-dominant negative mutant completely abolished AT(2)-mediated inhibition of EGFR and ERK activation. AT(1)-mediated c-fos mRNA accumulation was attenuated by 48% by AT(2) stimulation. Induction of fibronectin gene containing an AP-1 responsive element in its 5'-flanking region was decreased by 37% after AT(2) stimulation, corresponding to the results of gel mobility assay with the AP-1 sequence of fibronectin as a probe. These findings suggested that AT(2) inhibits ERK activity by inducing SHP-1 activity, leading to decreases in AP-1 activity and AP-1-regulated gene expression, in which EGFR dephosphorylation plays an important role via association of SHP-1.


Assuntos
Receptores ErbB/metabolismo , Proteínas Tirosina Fosfatases/metabolismo , Receptores de Angiotensina/fisiologia , Angiotensina II/farmacologia , Animais , Células Cultivadas , Fibronectinas/genética , Regulação da Expressão Gênica/efeitos dos fármacos , Imidazóis/farmacologia , Peptídeos e Proteínas de Sinalização Intracelular , Camundongos , Camundongos Transgênicos , Proteínas Quinases Ativadas por Mitógeno/efeitos dos fármacos , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Músculo Liso Vascular/citologia , Músculo Liso Vascular/efeitos dos fármacos , Músculo Liso Vascular/metabolismo , Fosforilação/efeitos dos fármacos , Fosfotirosina/efeitos dos fármacos , Fosfotirosina/metabolismo , Ligação Proteica/efeitos dos fármacos , Proteína Tirosina Fosfatase não Receptora Tipo 1 , Proteína Tirosina Fosfatase não Receptora Tipo 11 , Proteína Tirosina Fosfatase não Receptora Tipo 6 , Proteínas Proto-Oncogênicas c-fos/genética , Piridinas/farmacologia , RNA Mensageiro/efeitos dos fármacos , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Receptor Tipo 1 de Angiotensina , Receptor Tipo 2 de Angiotensina , Receptores de Angiotensina/genética , Fator de Transcrição AP-1/efeitos dos fármacos , Fator de Transcrição AP-1/metabolismo
10.
Life Sci ; 69(5): 509-16, 2001 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-11510946

RESUMO

The recently cloned angiotensin II type 2 (AT2) receptor is a member of the seven transmembrane G-protein coupled receptor superfamily with a relatively low sequence homology with the angiotensin II type 1 (AT1) receptor subtype and counteracts the growth action of AT1 receptor. Intracellular third loops are known to be involved in interactions with various G proteins. We hypothesized that the intracellular third loop plays critical roles in determining the specificity of opposite functions of AT1 and AT2 receptor subtypes and examined this possibility using chimeric AT1 receptor, of which intracellular third loop is replaced with that of AT2 receptor. We transfected this chimeric receptor into PC 12 cells and observed that stimulation of this receptor inhibited extracellular signal-regulated kinase (ERK) activation and induces apoptosis, whereas the binding characteristics of this receptor remained those of ATI receptor. Taken together, these results support the notion that intracellular third loop is the critical determinant for mutually antagonistic AT1 and AT2 receptors' signaling pathways.


Assuntos
Apoptose , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Receptores de Angiotensina/metabolismo , Animais , Técnicas de Transferência de Genes , Proteínas de Membrana/química , Proteínas de Membrana/metabolismo , Células PC12 , Estrutura Terciária de Proteína , Ratos , Receptor Tipo 1 de Angiotensina , Receptor Tipo 2 de Angiotensina , Receptores de Angiotensina/química , Proteínas Recombinantes de Fusão/química , Proteínas Recombinantes de Fusão/metabolismo
11.
Nihon Kokyuki Gakkai Zasshi ; 39(3): 205-9, 2001 Mar.
Artigo em Japonês | MEDLINE | ID: mdl-11431916

RESUMO

The patient, a 39-year-old man, presented in May 1997 with an untreated persistent cough with excessive sputum of 5 years' duration. He was admitted to hospital because of the severity of the symptoms and the presence of acid-fast bacilli in his sputum. These bacilli were identified as Mycobacterium tuberculosis by the polymerase chain reaction method. After treatment with antituberculous drugs was initiated, his symptoms and the patchy infiltrative shadows on his chest radiographs gradually resolved. However, the patient continued to expectorate a purulent sputum, showed diffuse micronodular shadows on chest radiographs, and had hypoxemia as well as mixed ventilatory and small airway disturbances on pulmonary function tests. We performed a video-assisted thoracoscopic biopsy of the lung, which revealed follicular bronchiolitis.


Assuntos
Bronquiolite/complicações , Tuberculose Pulmonar/complicações , Adulto , Bronquiolite/patologia , Humanos , Masculino , Tuberculose Pulmonar/patologia
12.
EMBO J ; 20(12): 2995-3007, 2001 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-11406576

RESUMO

Vav is a guanine nucleotide exchange factor for the Rho/Rac family that is expressed exclusively in hematopoietic cells. Growth factor receptor-bound protein 2 (Grb2) has been proposed to play important roles in the membrane localization and activation of Vav through dimerization of its C-terminal Src-homology 3 (SH3) domain (GrbS) and the N-terminal SH3 domain of Vav (VavS). The crystal structure of VavS complexed with GrbS has been solved. VavS is distinct from other SH3 domain proteins in that its binding site for proline-rich peptides is blocked by its own RT loop. One of the ends of the VavS beta-barrel forms a concave hydrophobic surface. The GrbS components make a contiguous complementary interface with the VavS surface. The binding site of GrbS for VavS partially overlaps with the canonical binding site for proline-rich peptides, but is definitely different. Mutations at the interface caused a decrease in the binding affinity of VavS for GrbS by 4- to 40-fold. The structure reveals how GrbS discriminates VavS specifically from other signaling molecules without binding to the proline-rich motif.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal , Proteínas de Ciclo Celular , Receptores ErbB/química , Fatores de Troca do Nucleotídeo Guanina/química , Proteínas/química , Proteínas Proto-Oncogênicas/química , Domínios de Homologia de src , Sequência de Aminoácidos , Animais , Cristalografia por Raios X , Receptores ErbB/genética , Proteína Adaptadora GRB2 , Fatores de Troca do Nucleotídeo Guanina/genética , Humanos , Camundongos , Modelos Moleculares , Dados de Sequência Molecular , Mutagênese , Peptídeos/química , Prolina/química , Prolina/genética , Estrutura Secundária de Proteína , Proteínas/genética , Proteínas Proto-Oncogênicas/genética , Proteínas Proto-Oncogênicas c-vav , Proteínas Recombinantes de Fusão/química , Proteínas Recombinantes de Fusão/genética
13.
Exp Nephrol ; 9(3): 181-90, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11340302

RESUMO

Activation of certain cytokines and adhesion molecules has been postulated being involved in the pathogenesis of experimental and human glomerulonephritis. In this study, we examined whether the transcription factor, nuclear factor kappaB (NFkappaB), mediated the expression of these genes involved with the inflammatory response of mesangial cells by using transcription factor decoy oligodeoxynucleotides (ODN) to block NFkappaB binding to the promoter site of its target genes. We hypothesized that the NFkappaB decoy ODN can inhibit the coordinated activation of cytokines and adhesion molecules induced by TNF-alpha. Increased binding activity of NFkappaB induced by TNF-alpha was effectively blocked by the NFkappaB decoy ODN. TNF-alpha stimulated CAT expression, which was significantly inhibited by transfection of NFkappaB, but not by scrambled decoy ODN. Of importance, NFkappaB, but not scrambled decoy ODN, significantly attenuated the increase in RNA and protein levels of IL-1alpha, IL-1beta, IL-6, ICAM-1 and VCAM-1 induced by TNF-alpha assessed by RT-PCR. Moreover, in vivo transfection of NFkappaB decoy ODN inhibited expressions of these cytokines and adhesion molecules induced by TNF-alpha injection. These results suggest a novel therapeutic strategy for the treatment of glomerulonephritis using decoy ODN to block the binding of NFkappaB, inhibiting the coordinated transactivation of the key cytokines and adhesion molecules, and thereby suppressing the inflammatory process.


Assuntos
Moléculas de Adesão Celular/biossíntese , Citocinas/biossíntese , Mesângio Glomerular/metabolismo , NF-kappa B/antagonistas & inibidores , Fator de Necrose Tumoral alfa/farmacologia , Animais , Sítios de Ligação , Linhagem Celular Transformada , Ensaio de Imunoadsorção Enzimática , Técnicas In Vitro , Molécula 1 de Adesão Intercelular/metabolismo , Lipossomos , Camundongos , Camundongos Endogâmicos C57BL , Microscopia de Fluorescência , NF-kappa B/biossíntese , NF-kappa B/genética , Oligonucleotídeos/genética , Respirovirus/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transfecção , Molécula 1 de Adesão de Célula Vascular/metabolismo
14.
Biochem Biophys Res Commun ; 282(5): 1085-91, 2001 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-11302725

RESUMO

Angiotensin II (Ang II) has two major receptor isoforms, AT1 and AT2. AT1 transphosphorylates Ca(2+)-sensitive tyrosine kinase Pyk2 to activate c-Jun NH2-terminal kinase (JNK). Although AT2 inactivates extracellular signal-regulated kinase (ERK) via tyrosine phosphatases (PTP), the action of AT2 on Pyk2 and JNK remains undefined. Using AT2-overexpressing vascular smooth muscle cells (AT2-VSMC) from AT2-transgenic mice, we studied these undefined actions of AT2. AT1-mediated JNK activity was increased 2.2-fold by AT2 inhibition, which was abolished by orthovanadate. AT2 did not affect AT1-mediated Pyk2 phosphorylation, but attenuated c-Jun mRNA accumulation by 32%. The activity of src-homology 2 domain-containing PTP (SHP-1) was significantly upregulated 1 min after AT2 stimulation. Stable overexpression of SHP-1 dominant negative mutant in AT2-VSMC completely abolished AT2-mediated inhibition of JNK activation and c-Jun expression. These findings suggest that AT2 inhibits JNK activity by affecting the downstream signal of Pyk2 in a SHP-1-dependent manner, leading to a decrease in c-Jun expression.


Assuntos
Proteínas Quinases Ativadas por Mitógeno/metabolismo , Músculo Liso Vascular/metabolismo , Proteínas Tirosina Fosfatases/metabolismo , Proteínas Tirosina Quinases/metabolismo , Receptores de Angiotensina/metabolismo , Antagonistas de Receptores de Angiotensina , Animais , Cálcio/metabolismo , Células Cultivadas , Inibidores Enzimáticos/farmacologia , Quinase 2 de Adesão Focal , Genes Dominantes , Líquido Intracelular/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular , Proteínas Quinases JNK Ativadas por Mitógeno , Camundongos , Camundongos Transgênicos , Proteínas Quinases Ativadas por Mitógeno/antagonistas & inibidores , Proteínas Quinases Ativadas por Mitógeno/genética , Músculo Liso Vascular/citologia , Fosforilação/efeitos dos fármacos , Proteína Tirosina Fosfatase não Receptora Tipo 1 , Proteína Tirosina Fosfatase não Receptora Tipo 6 , Proteínas Tirosina Fosfatases/antagonistas & inibidores , Proteínas Tirosina Fosfatases/genética , RNA Mensageiro/metabolismo , Receptor Tipo 1 de Angiotensina , Receptor Tipo 2 de Angiotensina , Receptores de Angiotensina/genética , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/genética , Vanadatos/farmacologia
15.
Exp Lung Res ; 27(2): 157-71, 2001 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11258803

RESUMO

An association between Epstein-Barr virus (EBV) infection and fibroblast proliferation in the interstitial spaces of the lung has been suggested in idiopathic interstitial pneumonia. In this study we show that EBV can infect human lung fibroblasts in vitro. A primary-cultured human lung fibroblast cell line, designated CCD-32Lu, expressed EBV nuclear antigen 1 after coculture with lethally irradiated EBV producing cells. The infection further induced CCD-32Lu cells to produce the fibrogenic cytokines basic fibroblast growth factor (bFGF) and interleukin-1beta. These findings indicate that lung fibroblasts may be a target for EBV infection and suggest that EBV may play a role in increased production of these cytokines and induce fibroblast proliferation in idiopathic interstitial pneumonia.


Assuntos
Infecções por Vírus Epstein-Barr/metabolismo , Fator 2 de Crescimento de Fibroblastos/biossíntese , Fibroblastos/virologia , Herpesvirus Humano 4/fisiologia , Interleucina-1/biossíntese , Anticorpos Bloqueadores/farmacologia , Anticorpos Antivirais/imunologia , Western Blotting , Divisão Celular , Linhagem Celular , Técnicas de Cocultura , Ensaio de Imunoadsorção Enzimática , Antígenos Nucleares do Vírus Epstein-Barr/análise , Antígenos Nucleares do Vírus Epstein-Barr/metabolismo , Citometria de Fluxo , Imunofluorescência , Humanos , Pulmão/citologia , Doenças Pulmonares Intersticiais/etiologia , Doenças Pulmonares Intersticiais/metabolismo , Doenças Pulmonares Intersticiais/virologia , Testes de Neutralização , Fator de Crescimento Transformador beta/biossíntese , Fator de Crescimento Transformador beta1
16.
Hypertension ; 37(2 Pt 2): 581-6, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11230338

RESUMO

Hepatocyte growth factor (HGF), a member of the angiogenic growth factors, may play a pivotal role in the regulation of endothelial cells, inasmuch as HGF shows mitogenic and antiapoptotic actions in endothelial cells. Because the mechanism of these actions is still unclear, we examined the signal transduction system of HGF in human aortic endothelial cells. Treatment of endothelial cells with recombinant HGF (rHGF) resulted in a significant increase in DNA synthesis as assessed by thymidine incorporation. Importantly, phosphorylation of extracellular signal-related kinase (ERK) and Akt by rHGF was clearly observed. Thus, we further examined the effects of specific inhibitors of ERK or Akt on cell proliferation. Pretreatment with PD98059, a mitogen-activated protein kinase kinase inhibitor, significantly attenuated cell proliferation induced by rHGF, whereas inhibitors of phosphatidylinositol-3-OH kinase, wortmannin, and LY-294002, did not. Interestingly, treatment with rHGF significantly increased the phosphorylation of the signal transducers and activators of transcription (STAT)3 (Ser727), whereas PD98059 attenuated the phosphorylation of Ser727 induced by rHGF. In addition, treatment with rHGF significantly increased the promoter activity of c-fos, which includes the sis-inducible element and serum response element, whereas PD98059 completely attenuated the activation of the c-fos promoter induced by rHGF. In contrast, inhibition of Akt by wortmannin and LY-294002 failed to inhibit the phosphorylation of STAT3 and c-fos activation. On the other hand, treatment with rHGF attenuated the increase in LDH release and caspase-3 activity induced by tumor necrosis factor-alpha stimulation. In contrast to DNA synthesis, wortmannin and LY-294002 markedly attenuated the decrease in caspase-3 activity mediated by rHGF, whereas PD98059 did not. Overall, the present study demonstrated that HGF stimulated cell proliferation through the ERK-STAT3 (Ser727) pathway and had an antiapoptotic action through the phosphatidylinositol-3-OH kinase-Akt pathway in human aortic endothelial cells. These findings provide new perspectives in the role of HGF in cardiovascular disease.


Assuntos
Proteínas de Ligação a DNA/metabolismo , Endotélio Vascular/efeitos dos fármacos , Fator de Crescimento de Hepatócito/farmacologia , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Proto-Oncogênicas , Transativadores/metabolismo , Androstadienos/farmacologia , Apoptose/efeitos dos fármacos , Caspase 3 , Inibidores de Caspase , Caspases/metabolismo , Divisão Celular/efeitos dos fármacos , Células Cultivadas , Cromonas/farmacologia , Endotélio Vascular/metabolismo , Inibidores Enzimáticos/farmacologia , Flavonoides/farmacologia , Humanos , Proteínas Quinases Ativadas por Mitógeno/antagonistas & inibidores , Morfolinas/farmacologia , Fosforilação/efeitos dos fármacos , Regiões Promotoras Genéticas , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Proteínas Proto-Oncogênicas c-akt , Proteínas Proto-Oncogênicas c-fos/genética , Proteínas Recombinantes/farmacologia , Fator de Transcrição STAT3 , Transdução de Sinais , Fator de Necrose Tumoral alfa , Wortmanina
17.
Cardiovasc Res ; 49(4): 863-71, 2001 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11230986

RESUMO

OBJECTIVE: To examine the possible crosstalk and the roles of angiotensin (Ang) II type 1 (AT1) and type 2 (AT2) receptors in the control of apoptosis in fetal vascular smooth muscle cells (VSMCs). METHODS: Fetal VSMCs were prepared from rat fetal aorta at embryonic day 20. Expression of Ang II receptors was measured by a radioligand binding assay. Apoptotic changes were assessed by caspase 3 activity and chromatin dye staining. Regulation of extracellular signal-regulated kinase (ERK) activity via Ang II receptors was analysed by determining phosphorylated ERK with Western blot. Ang II receptor-mediated activation of tyrosine phosphatase SHP-1 was assessed by protein tyrosine phosphatase assay. RESULTS: The expression of AT1 and AT2 receptors was approximately 70%: 30% per cell. Serum depletion induced apoptosis in fetal VSMCs and selective AT1 receptor stimulation attenuated the apoptotic changes, whereas selective AT2 receptor activation enhanced apoptosis. Ang II increased ERK phosphorylation, which was inhibited by addition of the AT1 receptor-specific antagonist CV11974, but enhanced by addition of the AT2 receptor-specific antagonist PD123319, suggesting that activation of AT2 receptor attenuated the AT1 receptor-mediated ERK phosphorylation. Moreover, we demonstrated that AT2 receptor stimulation activated SHP-1 in fetal VSMCs, whereas AT1 receptor stimulation did not. Transient transfection of a dominant-negative SHP-1 mutant into rat fetal VSMCs resulted in a significant decrease of the AT2 receptor-mediated inhibition of ERK phosphorylation and attenuated the proapoptotic effect of AT2 receptor. CONCLUSION: These results indicate that a crosstalk between AT1 and AT2 receptors regulates the survival of fetal VSMCs and substantiate SHP-1 as a key molecule in AT2 receptor signaling.


Assuntos
Angiotensina II/metabolismo , Apoptose , Músculo Liso Vascular/embriologia , Proteínas Tirosina Fosfatases/metabolismo , Receptor Cross-Talk , Receptores de Angiotensina/metabolismo , Análise de Variância , Animais , Células Cultivadas , Ativação Enzimática , Immunoblotting , Peptídeos e Proteínas de Sinalização Intracelular , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Músculo Liso Vascular/enzimologia , Fosforilação , Proteína Tirosina Fosfatase não Receptora Tipo 1 , Proteína Tirosina Fosfatase não Receptora Tipo 6 , Ratos , Ratos Sprague-Dawley , Receptor Tipo 1 de Angiotensina , Receptor Tipo 2 de Angiotensina
18.
EMBO J ; 20(3): 377-86, 2001 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-11157745

RESUMO

A conformational conversion of the normal, protease- sensitive prion protein (PrP-sen or PrP(C)) to a protease-resistant form (PrP-res or PrP(Sc)) is commonly thought to be required in transmissible spongiform encephalopathies (TSEs). Endogenous sulfated glycosaminoglycans are associated with PrP-res deposits in vivo, suggesting that they may facilitate PrP-res formation. On the other hand, certain exogenous sulfated glycans can profoundly inhibit PrP-res accumulation and serve as prophylactic anti-TSE compounds in vivo. To investigate the seemingly paradoxical effects of sulfated glycans on PrP-res formation, we have assayed their direct effects on PrP conversion under physiologically compatible cell-free conditions. Heparan sulfate and pentosan polysulfate stimulated PrP-res formation. Conversion was stimulated further by increased temperature. Both elevated temperature and pentosan polysulfate promoted interspecies PrP conversion. Circular dichroism spectropolarimetry measurements showed that pentosan polysulfate induced a conformational change in PrP-sen that may potentiate its PrP-res-induced conversion. These results show that certain sulfated glycosaminoglycans can directly affect the PrP conversion reaction. Therefore, depending upon the circumstances, sulfated glycans may be either cofactors or inhibitors of this apparently pathogenic process.


Assuntos
Proteínas PrPC/química , Proteínas PrPC/metabolismo , Proteínas PrPSc/química , Proteínas PrPSc/metabolismo , Animais , Sistema Livre de Células , Dicroísmo Circular , Cricetinae , Endopeptidases/metabolismo , Temperatura Alta , Técnicas In Vitro , Camundongos , Poliéster Sulfúrico de Pentosana/farmacologia , Doenças Priônicas/etiologia , Doenças Priônicas/metabolismo , Doenças Priônicas/prevenção & controle , Conformação Proteica/efeitos dos fármacos
19.
Neuropathology ; 21(4): 278-87, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11837534

RESUMO

A 68-year-old man was admitted to St Marianna University Hospital on account of loss of consciousness with left hemiplegia. During the hospital recovery course with a rehabilitation procedure, the patient's blood pressure was very unstable, fluctuating between high (210/110 mmHg) and low (110/70 mmHg) values accompanied by a fainting sensation. A second stroke of left hemiplegia took place 1 month later. Afterwards, his condition worsened to tetraplegia with dysarthria. Three months later, lung cancer with multiple metastasis including his left neck was found and he died from adynamic ileus 6 months after the onset of the present illness. Autopsy revealed nearly complete atheromatous obstruction and more than 50% stenosis, respectively, of his right common and internal/external carotid arteries. His intracranial arterial trunks and main branches were all patent with localized atherosclerosis of only moderate degree. The pathology of the brain existed predominantly in the right hemisphere in the border zone area between the anterior and middle cerebral arteries systematically with numerous disseminated foci of complete or incomplete necrosis, white matter and gray matter being involved independently. Involvement of centrum semiovale white matter is more extensive and intensive than that of gray matter. Of the gray matter, cerebral cortex as well as striatum, periventricular (the third ventricle) gray and cerebellar cortex was involved. The specific characteristic topography and distribution of the lesions together with their histopathology are described in detail with illustration. It is concluded that this case represents an outstanding example of hemodynamic cerebral circulatory insufficiency doubly caused by hemilateral carotid artery stenosis and repeated episodes of systemic hypotension.


Assuntos
Doenças das Artérias Carótidas/patologia , Infarto Cerebral/patologia , Lateralidade Funcional , Hipotensão/patologia , Idoso , Artéria Carótida Primitiva/patologia , Artéria Carótida Externa/patologia , Artéria Carótida Interna/patologia , Infarto Cerebral/etiologia , Evolução Fatal , Humanos , Masculino , Necrose
20.
Gan To Kagaku Ryoho ; 28 Suppl 1: 154-7, 2001 Dec.
Artigo em Japonês | MEDLINE | ID: mdl-11787285

RESUMO

The patient, who is received home enteral nutrition (HEN) for a long time in a day, has problems on moving all days. Now, we tried Portermate, which is new portable devices for HEN, in his clinical care. The patient is chronic pancreatitis, and his clinical problems becomes to be worse after he ate. He was under total enteral nutrition via jejunostomy. His clinical complications were almost controlled after HEN, but he has a few complains receiving enteral nutrition. He would not move easily, for an old HEN system was not compact to move. Portermate made him go everywhere he wanted any time. It extremely improved his QOL under HEN. He continues to use Portermate.


Assuntos
Nutrição Enteral/instrumentação , Serviços de Assistência Domiciliar , Pancreatite/terapia , Qualidade de Vida , Atividades Cotidianas , Adulto , Doença Crônica , Humanos , Masculino
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA