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1.
Environ Toxicol ; 28(1): 21-30, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21384493

RESUMO

Chlorinated benz[a]anthracenes (Cl-BaA) are halogenated aromatic compounds (typified by dioxins) found in the environment at relatively high concentrations. Fischer 344 rats were intragastrically administered 0, 1, or 10 mg of Cl-BaA or its parent compound benz[a]anthracene (BaA) per kg of body weight for 14 consecutive days. Both chemicals at 10 mg/kg/day inhibited the gain in body weight, and consequent increase in relative liver weight. Hepatic gene expression of cytochrome P450 (CYP) 1A1, 1A2, and 1B1 was significantly stimulated by administration of BaA (10 mg/kg/day) compared with the control. After administration of Cl-BaA, only the CYP1A2 gene was significantly induced, even at the lower dosage; CYP1A1 and 1B1 mRNA levels remained unchanged in Cl-BaA-treated rats compared with controls. To elucidate the role of such Cl-BaA exposure and induced CYPs at toxicity onset, we investigated the mutagenicity of BaA and Cl-BaA using Salmonella typhimurium TA98 and TA100. BaA and Cl-BaA at 10 µg/plate produced positive results in both strains in the presence of rat S-9. Incubation of Cl-BaA with recombinant rat CYP1A2 produced a significantly higher number of revertant colonies in TA98 and TA100 than in controls, but no such change was observed for BaA. In conclusion, BaA changes its own physiological and toxicological actions by its chlorination; (1) daily exposure to Cl-BaA selectively induces hepatic CYP1A2 in rats and (2) Cl-BaA induces frameshift mutations in the presence of CYP1A2, although BaA does not exert mutagenicity. This indicates that CYP1A2 may metabolize Cl-BaA to active forms.


Assuntos
Benzo(a)Antracenos/toxicidade , Fígado/efeitos dos fármacos , Mutagênicos/toxicidade , Salmonella typhimurium/efeitos dos fármacos , Animais , Hidrocarboneto de Aril Hidroxilases/metabolismo , Citocromo P-450 CYP1A1/metabolismo , Citocromo P-450 CYP1A2 , Citocromo P-450 CYP1B1 , Citocromos/metabolismo , Mutação da Fase de Leitura , Regulação da Expressão Gênica/efeitos dos fármacos , Halogenação , Fígado/metabolismo , Masculino , Testes de Mutagenicidade , Ratos , Ratos Endogâmicos F344 , Salmonella typhimurium/metabolismo
2.
Sci Rep ; 13(1): 9514, 2023 06 12.
Artigo em Inglês | MEDLINE | ID: mdl-37308504

RESUMO

A major trade-off of land-use change is the potential for increased risk of infectious diseases, a.o. through impacting disease vector life-cycles. Evaluating the public health implications of land-use conversions requires spatially detailed modelling linking land-use to vector ecology. Here, we estimate the impact of deforestation for oil palm cultivation on the number of life-cycle completions of Aedes albopictus via its impact on local microclimates. We apply a recently developed mechanistic phenology model to a fine-scaled (50-m resolution) microclimate dataset that includes daily temperature, rainfall and evaporation. Results of this combined model indicate that the conversion from lowland rainforest to plantations increases suitability for A. albopictus development by 10.8%, moderated to 4.7% with oil palm growth to maturity. Deforestation followed by typical plantation planting-maturation-clearance-replanting cycles is predicted to create pulses of high development suitability. Our results highlight the need to explore sustainable land-use scenarios that resolve conflicts between agricultural and human health objectives.


Assuntos
Aedes , Humanos , Animais , Conservação dos Recursos Naturais , Microclima , Mosquitos Vetores , Vetores de Doenças
3.
Kyobu Geka ; 62(6): 500-3, 2009 Jun.
Artigo em Japonês | MEDLINE | ID: mdl-19522214

RESUMO

We report a 27-year-old woman who underwent off-pump coronary artery bypass grafting (OPCAB) for angina pectoris with coronary artery aneurysm due to Kawasaki disease. At the age of 3, she was diagnosed as Kawasaki disease with coronary artery aneurysms in the right coronary artery and the left anterior descending artery. She was medically followed-up since then Because an enlarged aneurysm and a stenotic lesion were recognized in the right coronary artery, operation was indicated. In operation, the right coronary artery was ligated at the inflow and the outflow of the aneurysm. OPCAB was also conducted with the right internal thoracic artery anastomosed to the right coronary artery. Postoperative course was uneventful, and she was discharged at the day 5 after operation. Revascularization using arterial grafts, especially the internal thoracic arteries, may be the choice for young patients to expect a good patency rate in the long-term.


Assuntos
Angina Pectoris/etiologia , Angina Pectoris/cirurgia , Ponte de Artéria Coronária sem Circulação Extracorpórea , Ponte de Artéria Coronária , Síndrome de Linfonodos Mucocutâneos/complicações , Adulto , Anastomose Cirúrgica , Aneurisma Coronário/etiologia , Aneurisma Coronário/cirurgia , Vasos Coronários/cirurgia , Feminino , Humanos , Artéria Torácica Interna/cirurgia
4.
Kyobu Geka ; 62(1): 19-23, 2009 Jan.
Artigo em Japonês | MEDLINE | ID: mdl-19195181

RESUMO

We report the clinical results of 799 cases of isolated coronary artery bypass grafting (CABG) performed during the recent 5 years. We performed off-pump CABG (OPCAB) as standard operation, in which arterial grafts were mainly used. The mean number of distal anastomoses was 3.6 +/- 1.4 per patient Four hundred and fifty-five cases (57.0%) were done only with arterial grafts. Bilateral internal thoracic arteries were used in 326 cases. The mean number of saphenous vein grafts was 1.6 +/- 0.8 per patient. Continuous hemodiafiltraion (CHDF) was performed in 22 cases (2.8%) postoperatively. Among the OPCAB cases, 10 cases (1.3%) were converted to on-pump CABG. There were 7 cases (0.9%) of hospital death. The mean length of postoperative hospital stay was 10.2 +/- 5.3 days. The ratio of the patients with left main trunk disease and that of the patients who required postoperative CHDF increased year by year. The mean length of postoperative hospital stay decreased every year, and the reduced length was 2.7 days in the 5 years (8.7+/- 3.6 days in 2007). It is expected that patients who have severe calcified lesions or who are on hemodialysis may increase in the near future. In such cases, CABG rather than percutaneous catheter intervention may be suitable for revascularization. Therefore, not only appropriate choice of treatment strategies, but also accurate surgical techniques may become more importance.


Assuntos
Ponte de Artéria Coronária sem Circulação Extracorpórea/métodos , Idoso , Ponte de Artéria Coronária , Feminino , Humanos , Masculino , Resultado do Tratamento
5.
Eur J Trauma Emerg Surg ; 43(4): 431-438, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28093623

RESUMO

PURPOSE: The diagnostic criteria for disseminated intravascular coagulation (DIC) established by the Japanese Association for Acute Medicine (JAAM) is able to diagnose DIC accurately and promptly. The aim of this retrospective study is to evaluate the degree of association between each parameter of JAAM DIC criteria and the diagnosis of trauma induced DIC (T-DIC) utilizing thromboelastometry (ROTEM). METHODS: Trauma patients transported to our hospital with ROTEM performed in the emergency department between January 2013 and December 2015 were enrolled in this study. We evaluated (1) the characteristics of T-DIC, (2) the relationships between T-DIC and each parameter of the JAAM DIC criteria and (3) the diagnostic accuracies of each parameter for T-DIC by statistical measurement. RESULTS: All 72 patients (21 T-DIC and 51 control) were included in primary analysis. T-DIC was significantly related to younger age, more severe trauma scores, more cases of massive transfusions, and remarkable coagulation abnormality detected by standard coagulation tests. In the cases of T-DIC, ROTEM showed longer clotting time, lower acceleration, lower clot firmness, and inhibited fibrinolysis in EXTEM/INTEM. Within the JAAM DIC score, PT-INR ≥1.2 was the most accurate factor for T-DIC diagnosis; sensitivity 60.0%, specificity 100.0%, and accuracy 88.7%. PT-INR ≥1.2 was statistically correlated with the JAAM DIC score (p < 0.001, r = 0.709). The univariate analysis based on 1.2 of PT-INR indicated statistical differences in most categories of ROTEM, which is similar to analysis performed for the presence and absence of T-DIC. CONCLUSIONS: Among JAAM DIC criteria, the PT-INR ≥1.2 was the most accurate factor for both the diagnosis of T-DIC and the evaluation of its severity.


Assuntos
Coagulação Intravascular Disseminada/diagnóstico , Traumatismo Múltiplo/complicações , Tromboelastografia , Adulto , Fatores Etários , Idoso , Estudos de Casos e Controles , Coagulação Intravascular Disseminada/etiologia , Feminino , Humanos , Japão , Masculino , Pessoa de Meia-Idade , Guias de Prática Clínica como Assunto , Valor Preditivo dos Testes , Estudos Retrospectivos , Índice de Gravidade de Doença
6.
Cancer Res ; 57(6): 1206-12, 1997 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-9067294

RESUMO

The human pancreatic tumor cell line SUIT-2 was derived from a metastatic lesion in the liver of a patient with pancreatic adenocarcinoma. SUIT-2 and clonal cell lines derived from it show spontaneous metastasis to lung and regional lymph nodes from s.c. nude mouse xenografts and were found to express P-selectin mRNA and protein. Surface expression of P-selectin protein was increased by exposure of the pancreatic tumor cells to thrombin, oxygen radicals, and trypsin, suggesting that common cellular mechanisms for regulating P-selectin surface expression exist among platelets, endothelial cells, and these pancreatic tumor cells. The finding that P-selectin is expressed by metastatic pancreatic tumor cells demonstrates that the range of cell types that express these adhesion molecules is broader than believed previously.


Assuntos
Adenocarcinoma/secundário , Regulação Neoplásica da Expressão Gênica , Neoplasias Hepáticas/secundário , Proteínas de Neoplasias/biossíntese , Selectina-P/biossíntese , Neoplasias Pancreáticas/patologia , Adenocarcinoma/genética , Adenocarcinoma/patologia , Animais , Clonagem Molecular , Eletroforese em Gel de Poliacrilamida , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Neoplasias Hepáticas/genética , Camundongos , Camundongos Nus , Proteínas de Neoplasias/genética , Selectina-P/genética , Neoplasias Pancreáticas/genética , Reação em Cadeia da Polimerase , Espécies Reativas de Oxigênio , Técnica de Subtração , Trombina/farmacologia , Tripsina/farmacologia , Células Tumorais Cultivadas/efeitos dos fármacos
7.
Cancer Res ; 60(10): 2602-6, 2000 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-10825129

RESUMO

We report the characterization of a novel serine protease of the chymotrypsin family, recently isolated by cDNA-representational difference analysis, as a gene overexpressed in pancreatic cancer. The 2.3-kb mRNA of the gene, named TMPRSS3, is strongly expressed in a subset of pancreatic cancer and various other cancer tissues, and its expression correlates with the metastatic potential of the clonal SUIT-2 pancreatic cancer cell lines. The deduced polypeptide sequence consists of 437 amino acids and exhibits all of the structural features characteristic of serine proteases with trypsin-like activity. TMPRSS3 is membrane bound with a NH2-terminal signal-anchor sequence and a glycosylated extracellular region containing the serine protease domain. Thus, TMPRSS3 is a novel membrane-bound serine protease overexpressed in cancer, which may be of importance for processes involved in metastasis formation and tumor invasion.


Assuntos
Proteínas de Membrana , Proteínas de Neoplasias , Neoplasias Pancreáticas/enzimologia , Serina Endopeptidases/biossíntese , Serina Endopeptidases/genética , Sequência de Aminoácidos , Sequência de Bases , Western Blotting , Mapeamento Cromossômico , Regulação Enzimológica da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Biblioteca Gênica , Humanos , Dados de Sequência Molecular , Neoplasias Pancreáticas/genética , Biblioteca de Peptídeos , Células Tumorais Cultivadas
8.
Cancer Res ; 57(21): 4744-8, 1997 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-9354435

RESUMO

The levels of mRNA expression of three UDP-N-acetyl-alpha-D-galactosamine:polypeptide GalNAc N-acetylgalactosaminyltransferases (GalNAc-transferases) were quantified for human adenocarcinoma cell lines from pancreas, colon, stomach, and breast. Two of the GalNAc-transferases, GalNAc-T1 and GalNAc-T2, were expressed constitutively and at low levels in most or all cell lines examined. A third GalNAc-transferase, GalNAc-T3, was differentially expressed. Well-differentiated adenocarcinoma cell lines expressed high levels and moderately differentiated cell lines expressed lower levels of GalNAc-T3. Cell lines classified as poorly differentiated failed to express GalNAc-T3 mRNA at levels that could be detected by Northern blot analysis. Differential expression of the GalNAc-T3 protein was confirmed in these cell lines by Western blotting. We propose that glycosylation in tumor cell lines may be regulated in part by differential expression of GalNAc-transferases, and we suggest that GalNAc-T3 gene expression may be a molecular indicator of differentiated adenocarcinoma.


Assuntos
Adenocarcinoma/enzimologia , N-Acetilgalactosaminiltransferases/metabolismo , Proteínas de Neoplasias/metabolismo , Actinas/metabolismo , Adenocarcinoma/patologia , Western Blotting , Neoplasias da Mama/enzimologia , Neoplasias do Colo/enzimologia , Humanos , N-Acetilgalactosaminiltransferases/genética , Proteínas de Neoplasias/genética , Neoplasias Pancreáticas/enzimologia , Neoplasias Pancreáticas/patologia , RNA Mensageiro/metabolismo , Células Tumorais Cultivadas
9.
Oncogene ; 18(4): 1073-80, 1999 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-10023684

RESUMO

CTGF is an immediate early growth responsive gene that has been shown to be a downstream mediator of TGFbeta actions in fibroblasts and vascular endothelial cells. In the present study hCTGF was isolated as immediate early target gene of EGF/TGFalpha in human pancreatic cancer cells by suppression hybridization. CTGF transcripts were found in 13/15 pancreatic cancer cell lines incubated with 10% serum. In 3/7 pancreatic cancer cell lines EGF/TGFalpha induced a significant rise of CTGF transcript levels peaking 1-2 h after the start of treatment. TGFbeta increased CTGF transcript levels in 2/7 pancreatic cancer cell lines after 4 h of treatment and this elevation was sustained after 24 h. Only treatment with TGFbeta was accompanied by a parallel induction of collagen type I transcription. 15/19 human pancreatic cancer tissues were shown to overexpress high levels of CTGF transcripts. CTGF transcript levels in pancreatic cancer tissues and nude mouse xenograft tumors showed a good correlation to the degree of fibrosis. In situ hybridization and the nude mouse experiments revealed that in pancreatic cancer tissues, fibroblasts are the predominant site of CTGF transcription, whereas the tumor cells appear to contribute to a lesser extent. We conclude that CTGF may be of paramount importance for the development of the characteristic desmoplastic reaction in pancreatic cancer tissues.


Assuntos
Substâncias de Crescimento/genética , Peptídeos e Proteínas de Sinalização Intercelular , Proteínas de Neoplasias/genética , Neoplasias Pancreáticas/genética , Animais , Colágeno/metabolismo , Fator de Crescimento do Tecido Conjuntivo , Fator de Crescimento Epidérmico/metabolismo , Fator de Crescimento Epidérmico/farmacologia , Fibroblastos/metabolismo , Substâncias de Crescimento/metabolismo , Humanos , Proteínas Imediatamente Precoces/genética , Proteínas Imediatamente Precoces/metabolismo , Hibridização In Situ , Camundongos , Camundongos Nus , Proteínas de Neoplasias/metabolismo , Fatores de Tempo , Transcrição Gênica , Fator de Crescimento Transformador alfa/metabolismo , Fator de Crescimento Transformador alfa/farmacologia , Fator de Crescimento Transformador beta/metabolismo , Fator de Crescimento Transformador beta/farmacologia , Transplante Heterólogo , Células Tumorais Cultivadas/efeitos dos fármacos
10.
J Exp Clin Cancer Res ; 24(1): 127-33, 2005 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15945132

RESUMO

We previously reported that most cancer cell lines constitutively express various cytokines including IL-8. But how IL-8 gene expression is regulated in cancer cells is still unclear. p53 tumor suppressor gene plays an important role in the regulation of transcription and is mutated in cancer cell lines. We investigated whether p53 status affects the constitutive expression of IL-8 in human cancer cells. SUIT-2 and RERF-LCOK cancer cells constitutively produced high levels of IL-8 in culture medium. Both cell lines were shown to carry a p53 mutation, and constitutive NF-kappaB transcriptional activity. To analyze whether p53 status mediates IL-8 expression, the effect of wild-type p53 (wt-p53) gene transfer on activation of NF-kappaB was determined in both cell lines. ELISA showed that the IL-8 concentration in medium decreased dose dependently by transient expression of wt-p53. Western-blot analysis showed no marked change in NF-kappaB protein levels in cell nuclei. EMSA showed no repression of NF-kappaB binding activity after transient expression of wt-p53. In contrast, luciferase reporter studies indicated that transcriptional activity of NF-kappaB is suppressed by transfection of wt-p53. These results show that wt-p53 gene transfer inhibits IL-8 production and NF-kappaB transcription activity in cancer cells and suggest that constitutive IL-8 production in cancer cells is associated with mutation of p53.


Assuntos
Regulação Neoplásica da Expressão Gênica , Interleucina-8/metabolismo , Mutação/genética , Neoplasias/genética , Neoplasias/metabolismo , Proteína Supressora de Tumor p53/genética , Linhagem Celular Tumoral , Regulação para Baixo , Humanos , Proteínas I-kappa B/metabolismo , Interleucina-8/biossíntese , Inibidor de NF-kappaB alfa , NF-kappa B/metabolismo , Neoplasias/patologia
11.
J Bone Miner Res ; 16(1): 57-62, 2001 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11149490

RESUMO

An accurate assay method of 25-hydroxyvitamin D3 24-hydroxylase (24-hydroxylase) was established. Kidney mitochondria prepared from vitamin D-replete rats were treated with polyoxyethylenesorbitan monolaurate. The solubilized suspension was ultracentrifuged at 100,000g for 60 minutes and an aliquot of the supernatant was incubated under the saturating concentrations of substrate NADPH and the mitochondrial-type electron transferring proteins, adrenodoxin and NADPH-adrenodoxin reductase. Products were analyzed by high-performance liquid chromatography (HPLC) monitoring effluents at a wavelength of 265 nm. The maximal velocity of the enzyme in vitamin D-replete rats was 400 pmol/minute per mg of protein, which was considerably higher than those reported by previous authors who used intact kidney mitochondria as the enzyme source. In applying the new assay method, an interesting property was found; Michaelis constant of 24-hydroxylase for 25-hydroxyvitamin D3 [25(OH)D3] was 0.6 microM, which was 35-fold lower than that for 1alpha,25-dihydroxyvitamin D3 [1alpha,25(OH)2D3] which was 20.9 microM. This fact indicates that affinity of the enzyme to 25(OH)D3 is 35-fold higher than that to 1alpha,25(OH)2D3. These data suggest that 25(OH)D3 is the preferred substrate to 1alpha,25(OH)2D3.


Assuntos
25-Hidroxivitamina D3 1-alfa-Hidroxilase/metabolismo , Calcifediol/metabolismo , Calcitriol/metabolismo , 25-Hidroxivitamina D3 1-alfa-Hidroxilase/análise , Adrenodoxina/metabolismo , Animais , Cromatografia Líquida de Alta Pressão , Ferredoxina-NADP Redutase/metabolismo , Concentração de Íons de Hidrogênio , Rim/enzimologia , Rim/metabolismo , Cinética , Masculino , Mitocôndrias/enzimologia , Mitocôndrias/metabolismo , Polissorbatos/farmacologia , Ratos , Ratos Sprague-Dawley , Temperatura
12.
Clin Exp Metastasis ; 10(4): 259-66, 1992 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-1319859

RESUMO

A human pancreatic cancer cell line (SUIT-2) and four sublines cloned in vitro (S2-007, S2-013, S2-020 and S2-028) were inoculated into nude mice for assessment of metastatic potentials. After 16 weeks of subcutaneous injection, the parent SUIT-2 line metastasized to the lungs and lymph nodes in three of six mice. S2-007 cells presented the highest metastatic potential in pulmonary (5/6) and lymph node (2/6) metastases among the four sublines. No metastasis was found in S2-028. The incidence of spontaneous pulmonary metastasis was correlated with that of pulmonary colonization after intravenous (i.v.) injection of cell clusters (r = 0.87, P = 0.056). Pulmonary colonization potential using single cells, however, did not always reflect a spontaneous metastatic ability. Type I collagenolytic activity in serum-free conditioned media of these cells was correlated effectively with the incidence of spontaneous pulmonary metastasis (r = 0.92, P = 0.026) and pulmonary colonization after i.v. injection of cell clusters (r = 0.95, P = 0.013). Thus, type I collagenolytic activity may possibly be essential to spontaneous cancer metastasis.


Assuntos
Colágeno/metabolismo , Metástase Neoplásica/patologia , Neoplasias Pancreáticas/patologia , Animais , Humanos , Injeções Subcutâneas , Neoplasias Pulmonares/secundário , Metástase Linfática , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Colagenase Microbiana/metabolismo , Transplante de Neoplasias , Neoplasias Pancreáticas/enzimologia , Neoplasias Pancreáticas/metabolismo , Transplante Heterólogo , Células Tumorais Cultivadas
13.
Clin Exp Metastasis ; 12(3): 238-44, 1994 May.
Artigo em Inglês | MEDLINE | ID: mdl-8194199

RESUMO

The present study extends our investigations into the metastatic heterogeneity among four clonal cell lines (S2-007:H, S2-013:M1, S2-020:M2, and S2-028:L) from a human pancreatic cancer cell line (SUIT-2), and extends our discussion the positive correlation between metastatic potential and the type I collagenase activity of the cells, focusing on their interaction with extracellular matrix. Ability to attach to the reconstituted basement membrane (Matrigel) was higher for clone H than clone L during an observation period of 30-60 min, whereas clones M1 and M2 were found to be intermediate in ability. In densitometric and radioactive studies, clone L exhibited the lowest collagenolytic activity against mouse and human type IV collagen, while clone H exhibited the highest activity in the densitometric study and clone M1 was the highest in the radioactive study. The production of urinary-type plasminogen activator was highest in clone L and lowest in clone H. On the other hand, tissue-type plasminogen activator was highest in clone M2 and low in both clones H and L. Clone M2 exhibited the highest chemotactic activity toward diluted Matrigel, whereas clone L had the lowest activity. On the whole, these clones showed heterogenous interactions with an extracellular matrix. It is suggested that the attachment activity to basement membrane and the type IV collagenolytic activity of the cells may be positively correlated with their metastatic potential, whereas the production of urinary-type plasminogen activator was negatively correlated, but confirmation of these findings awaits further study.


Assuntos
Endopeptidases/metabolismo , Metástase Neoplásica , Neoplasias Pancreáticas/patologia , Adesão Celular , Linhagem Celular , Quimiotaxia , Células Clonais , Colágeno , Colagenases/metabolismo , Combinação de Medicamentos , Humanos , Laminina , Metaloproteinase 9 da Matriz , Ativadores de Plasminogênio/metabolismo , Proteoglicanas , Células Tumorais Cultivadas
14.
Clin Exp Metastasis ; 18(7): 561-71, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-11688961

RESUMO

Cell lines with high metastatic capacity to the lung were established by sequential passage of a human pancreatic cancer cell line (SUIT-2) through the lung of a nude mouse, via the lateral tail vein and from a subcutaneous inoculum. Cells of the parental SUIT-2 and sublines S2-VPx (x-cycle selection from SUIT-2 cells, by Vein-Pulmonary metastasis-culture) and S2-CPx (x-cycle selection, by Cutis-Pulmonary metastasis-culture) were injected intravenously or subcutaneously into nude mice to produce experimental or spontaneous lung metastasis. The S2-VP10 cell line produced pulmonary metastases in 100% of the nude mice, when injected intravenously. It failed, however, to produce more lung colonies than its parent cell line, when injected subcutaneously. The S2-CP8 cell line produced extensive pulmonary metastases in 100% of the nude mice, when injected either intravenously or subcutaneously. This study indicates that the nude mouse provided a good model for in vivo selection of metastatic cells from SUIT-2 cells both experimentally and spontaneously, and that the SUIT-2, S2-VPx, and S2-CPx cell lines will be valuable in the study of human cancer metastasis. We previously reported high levels of ezrin expression in the S2-VP10 and S2-CP8 cell lines. Here we show that these cell lines exhibit a greater capacity to invade or attach to various extracellular matrix components than the parent SUIT-2 cells. The S2-CP8 cell lines also exhibit greater level of type-I and type-IV collagen-degrading activity than the parent SUIT-2 cell line and the S2-VP10 cell line, which shows similar collagen-degrading activity to the parent SUIT-2 cells. In RT-PCR studies, SUIT-2, S2-CP8 and S2-VP10 cell lines constitutively expressed many matrix metalloproteinases (MMP-1, MMP-2, MMP-3, MMP7, MMP-9, MMP-10 and MMP-14). These results suggest that some parameters that enhance adhesion and invasion are important to both experimental and spontaneous metastasis and the collagen degrading enzymes are predicted to play a key-role during spontaneous metastasis.


Assuntos
Colágeno/metabolismo , Neoplasias Pulmonares/secundário , Neoplasias Pancreáticas/enzimologia , Animais , Adesão Celular , Divisão Celular , Colágeno Tipo I/metabolismo , Colágeno Tipo IV/metabolismo , Feminino , Humanos , Cinética , Metaloproteinases da Matriz/biossíntese , Metaloproteinases da Matriz/genética , Camundongos , Camundongos Nus , Invasividade Neoplásica , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/patologia , Inibidores Teciduais de Metaloproteinases/biossíntese , Inibidores Teciduais de Metaloproteinases/genética , Células Tumorais Cultivadas
15.
J Biochem ; 97(4): 1101-10, 1985 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-2993258

RESUMO

In connection with the characterization of two DNA polymerases (DPols) of Chlorella, we have extensively surveyed the literature on inhibition studies on DPols in various eukaryotes. By applying Tamiya's plot (1), we have obtained two parameters for each of the inhibitors, phi- and n-values, which express the enzyme sensitivity to the drug and the number of inhibitor molecules present in the enzyme-inhibitor complex that is principally involved in the inhibition, respectively. By inspecting these parameters for the three mammalian DPols, alpha-, beta-, and gamma-pols, as well as other eukaryotic DPols, we have found that: [1] inhibitors commonly utilized for characterizing various DPols can be classified into two major groups, each having two subgroups, on the basis of a comparison of the phi values among alpha-, beta-, and gamma-pols. Moreover, the grouping seems not to be merely coincidental, but to be intrinsically related to facets of the enzyme reaction, which may be taken to reflect evolutionary differences in DPol structure and function among the three DPols; [2] the remarkable n value, n = 1/2, that has been found for the inhibitors competitive with dCTP in Chlorella DPols has also been detected widely in many other eukaryotic DPols. Based on the first finding as well as many other data on various DPols, we have proposed an evolutionary scenario for eukaryotic DPols. Based on the second finding, we have hypothesized a novel role for dCTP as a cofactor, probably an apparent allosteric effector, in the nucleotide transfer reaction mechanism.


Assuntos
Inibidores da Síntese de Ácido Nucleico , Afidicolina , Arabinofuranosilcitosina Trifosfato/farmacologia , Evolução Biológica , Cátions Bivalentes , Clorófitas , Nucleotídeos de Desoxicitosina/fisiologia , Didesoxinucleotídeos , Difosfatos/farmacologia , Diterpenos/farmacologia , Etídio/farmacologia , Etilmaleimida/farmacologia , Nucleotídeos de Timina/farmacologia
16.
J Biochem ; 96(2): 461-73, 1984 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-6501253

RESUMO

Previously, we reported two DNA polymerases (DPols), Pol I and Pol II, in the unicellular green alga, Chlorella (Aoshima, J., Nishimura, T., & Iwamura, T. (1982) Cell Struc. Funct. 7, 71-86). Changes in their activities during the cell cycle either in the normal and drug-inhibited courses indicated that Pol I and Pol II functioned to replicate nuclear and chloroplast DNAs, respectively. In the present work, we have examined their enzymic properties to characterize and distinguish them further. A number of inhibitors commonly used for such studies were also tested to determine their effects and the results were analyzed by use of the simple and useful "Tamiya plot." We have also analyzed the data obtained in inhibitor studies on various eukaryotic DPols in the literature using the Tamiya plot, and the results will be presented elsewhere (Iwamura, T. & Aoshima, J. (1984) J. Biochem. in press). Comparisons of the algal DPols with mammalian enzymes as regards enzymic properties and inhibition modes have led us to conclude that: [1] the algal two DPols are significantly different from each other, despite having many similarities to each other: [2] they are related in properties to any of the three mammalian DPols-alpha, -beta, and -gamma; Pol I (n-DPol) was a little more like alpha than Pol II (ch-DPol), which in turn more akin to gamma. This feature was quantitized by using vectors in a three-dimensional alpha-beta-gamma-space. Another peculiar feature derived from the Tamiya plot of the inhibitions by araCTP and aphidicolin (both being competitive with cCTP) has led us to propose a specific allosteric role of cCTP in the reaction mechanism besides its role as one of the substrates.


Assuntos
Chlorella/enzimologia , DNA Polimerase II/isolamento & purificação , DNA Polimerase I/isolamento & purificação , Cátions Bivalentes , DNA Polimerase I/metabolismo , DNA Polimerase II/metabolismo , DNA Polimerase III/metabolismo , Desoxirribonucleotídeos/metabolismo , Cinética
17.
J Biochem ; 128(2): 301-7, 2000 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10920266

RESUMO

Cellular genes including the type I interferon genes are activated in response to viral infection. We previously reported that IRF-3 (interferon regulatory factor 3) is specifically phosphorylated on serine residues and directly transmits a virus-induced signal from the cytoplasm to the nucleus, and then participates in the primary phase of gene induction. In this study, we analyzed the molecular mechanism of IRF-3 activation further. The formation of a stable homomeric complex of IRF-3 between the specifically phosphorylated IRF-3 molecules occurred. While virus-induced IRF-7 did not bind to p300, the phosphorylated IRF-3 complex formed a stable multimeric complex with p300 (active holocomplex). Competition using a synthetic phosphopeptide corresponding to the activated IRF-3 demonstrated that p300 directly recognizes the structure in the vicinity of the phosphorylated residues of IRF-3. These results indicated that the phosphorylation of serine residues at positions 385 and 386 is critical for the formation of the holocomplex, presumably through a conformational switch facilitating homodimer formation and the generation of the interaction interface with CBP/p300.


Assuntos
Proteínas de Ligação a DNA/metabolismo , Vírus da Doença de Newcastle/fisiologia , Proteínas Nucleares/metabolismo , Transativadores/metabolismo , Fatores de Transcrição/metabolismo , Animais , Ligação Competitiva , Linhagem Celular , Proteínas de Ligação a DNA/genética , Proteína p300 Associada a E1A , Fator Regulador 3 de Interferon , Fator Regulador 7 de Interferon , Camundongos , Fosfopeptídeos/metabolismo , Fosforilação , Mutação Puntual , Testes de Precipitina , Serina/genética , Fatores de Transcrição/genética
18.
Eur J Pharmacol ; 291(3): 367-73, 1995 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-8719422

RESUMO

We investigated the binding characteristics of dihydroetorphine, 7,8-dihydro-7 alpha-[1-(R)-hydroxy-1-methylbutyl]-6, 14-endoethanotetrahydro-oripavine, and its effect on the inhibitory system of cyclic AMP production using cloned mu-, delta- and kappa-opioid receptors expressed on Chinese hamster ovary cells. The Ki values of dihydroetorphine for the mu-, delta- and kappa-opioid receptors were 4.5 x 10(-10). 1.8 x 10(-9) and 5.7 x 10(-10) M, respectively. On the other hand, those of morphine were 1.9 x 10(-9), 1.4 x 10(-6) and 1.3 x 10(-7) M, respectively. Through all of these three types of opioid receptors, dihydroetorphine inhibited forskolin (10 microM)-stimulated cyclic AMP production via pertussis toxin-sensitive G protein(s), and the inhibitory effects were antagonized by co-application with opioid receptor antagonists. The IC50 values of dihydroetorphine for the inhibition of cyclic AMP production through the mu-, delta- and kappa-opioid receptors were 4.2 x 10(-11), 8.6 x 10(-10) and 4.3 x 10(-9) M. respectively. On the other hand, those of morphine were 2.6 x 10(-8), 2.6 x 10(-6) and 1.9 x 10(-6) M, respectively. These results indicate that dihydroetorphine, unlike morphine which preferentially binds the mu-opioid receptor, binds not only mu- but also delta- and kappa-opioid receptors with high affinity and acts as a more potent agonist than morphine for all of the three types of receptors.


Assuntos
Etorfina/análogos & derivados , Receptores Opioides delta/efeitos dos fármacos , Receptores Opioides kappa/efeitos dos fármacos , Receptores Opioides mu/efeitos dos fármacos , Animais , Células CHO , Clonagem Molecular , Colforsina/farmacologia , Cricetinae , Etorfina/farmacologia , Antagonistas de Entorpecentes/farmacologia , Entorpecentes/farmacologia , Toxina Pertussis , Receptores Opioides delta/metabolismo , Receptores Opioides kappa/metabolismo , Receptores Opioides mu/metabolismo , Proteínas Recombinantes/metabolismo , Fatores de Virulência de Bordetella/farmacologia
19.
Pancreas ; 21(4): 392-8, 2000 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11075994

RESUMO

We studied the effect of tumor necrosis factor alpha (TNFalpha), one of the major inflammatory cytokines, on the adhesive reaction of pancreatic cancer cells to human umbilical vein endothelial cells (HUVECs) and on the hepatic metastasis of cancer cells in vivo. After TNFalpha stimulation, the expression of E-selectin, an adhesion molecule to neutrophils on HUVECs, increased. In addition, the adhesion of pancreatic cancer cells to HUVECs increased after TNFalpha stimulation, as was observed with neutrophils. The TNFalpha-induced adhesive response depended on the extent of sialyl Lewis(a) expression on cancer cells. The hepatic metastasis in vivo was often observed when cancer cells expressing a high amount of sialyl Lewis(a) were inoculated intrasplenically after increase in plasma TNFalpha concentration by lipopolysaccharide administration. Because sialyl Lewis(a) on cancer cells is a ligand for E-selectin on HUVECs, as sialyl Lewis(x) on neutrophils, TNFalpha upregulated the adhesive interaction between sialyl Lewis(a) on cancer cells and E-selectin on HUVECs. These results suggest that production of TNFalpha after surgical trauma may stimulate the hematogenic metastasis of cancer cells with a high sialyl Lewis(a) expression.


Assuntos
Endotélio Vascular/efeitos dos fármacos , Neoplasias Pancreáticas/patologia , Fator de Necrose Tumoral alfa/farmacologia , Animais , Adesão Celular/efeitos dos fármacos , Células Cultivadas , Selectina E/análise , Endotélio Vascular/citologia , Humanos , Lipopolissacarídeos/farmacologia , Neoplasias Hepáticas/secundário , Camundongos , Camundongos SCID , Neutrófilos/efeitos dos fármacos , Neutrófilos/fisiologia , Fator de Necrose Tumoral alfa/análise
20.
Chem Commun (Camb) ; (19): 1958-9, 2001 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-12240238

RESUMO

The tandem Michael-aldol reaction of 1-[2-(methylsulfanyl)-phenyl]prop-2-en-1-one (1) or the seleno congener 4 with p-nitrobenzaldehyde in the presence of BF3.Et2O gave the Baylis-Hillman adduct 2 or 5 and onium salt 3 or 6, respectively, and selenochromanone 7 from 4.

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