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1.
MRS Bull ; 47(11): 1092-1102, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36349118

RESUMO

Abstract: The grand challenge of "net-zero carbon" emission calls for technological breakthroughs in energy production. The traveling wave reactor (TWR) is designed to provide economical and safe nuclear power and solve imminent problems, including limited uranium resources and radiotoxicity burdens from back-end fuel reprocessing/disposal. However, qualification of fuels and materials for TWR remains challenging and it sets an "end of the road" mark on the route of R&D of this technology. In this article, a novel approach is proposed to maneuver reactor operations and utilize high-temperature transients to mitigate the challenges raised by envisioned TWR service environment. Annular U-50Zr fuel and oxidation dispersion strengthened (ODS) steels are proposed to be used instead of the current U-10Zr and HT-9 ferritic/martensitic steels. In addition, irradiation-accelerated transport of Mn and Cr to the cladding surface to form a protective oxide layer as a self-repairing mechanism was discovered and is believed capable of mitigating long-term corrosion. This work represents an attempt to disruptively overcome current technological limits in the TWR fuels. Impact statement: After the Fukushima accident in 2011, the entire nuclear industry calls for a major technological breakthrough that addresses the following three fundamental issues: (1) Reducing spent nuclear fuel reprocessing demands, (2) reducing the probability of a severe accident, and (3) reducing the energy production cost per kilowatt-hour. An inherently safe and ultralong life fast neutron reactor fuel form can be such one stone that kills the three birds. In light of the recent development findings on U-50Zr fuels, we hereby propose a disruptive, conceptual metallic fuel design that can serve the following purposes at the same time: (1) Reaching ultrahigh burnup of above 40% FIMA, (2) possessing strong inherent safety features, and (3) extending current limits on fast neutron irradiation dose to be far beyond 200 dpa. We believe that this technology will be able to bring about revolutionary changes to the nuclear industry by significantly lowering the operational costs as well as improving the reactor system safety to a large extent. Supplementary information: The online version contains supplementary material available at 10.1557/s43577-022-00420-4.

2.
Yi Chuan ; 31(8): 849-54, 2009 Aug.
Artigo em Zh | MEDLINE | ID: mdl-19689947

RESUMO

Hybrid rice breeding is the combining ability breeding. Screening hybrid rice combinations with high special combining ability (SCA) is able to breed strong superiority combinations with practical values. In this study, the genetic distances (GD) of nine three-line hybrid rice (5 CMS lines and 4 restorer lines) were examined using SSR markers. Based on yield performances of 20 hybrid crosses (5 x 4 NCII), the relationships between SCA, heterosis and GD were studied. The correlations of yield SCA with the control heterosis (r1=0.5609) and the average heterosis (r2=0.541) were significant, but not significant with GD (r=0.2143). Thus, the heterosis can be reflected by SCA; the hybrid parents selected in this study can be used to develop strong superiority combinations; but the SCA cannot be reflected by GD, which needs further study.


Assuntos
Quimera/genética , Vigor Híbrido , Oryza/genética , Cruzamento , Quimera/classificação , Quimera/crescimento & desenvolvimento , Oryza/classificação , Oryza/crescimento & desenvolvimento , Fenótipo , Filogenia
3.
World J Gastroenterol ; 13(11): 1752-4, 2007 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-17461483

RESUMO

A 62-year-old man presented with upper abdominal discomfort underwent upper gastrointestinal endoscopy. Gastroscopy and endoscopic ultrasonography revealed a submucosal tumor (SMT) with homogenous echogenicity originated from extragastric organs. An abdominal contrast-enhanced computed tomography (CT) showed that the well-marginated ovoid mass, approximately 6 cm in diameter, enhanced homogenously to a similar degree as splenic parenchyma. (99m)Technetium sulfur colloid scintigraphy revealed the splenic nature of the mass. A diagnosis of accessory spleen mimicking gastric SMT was made. Subsequent follow-up was uneventful without performing splenectomy.


Assuntos
Baço/anormalidades , Baço/diagnóstico por imagem , Neoplasias Gástricas/diagnóstico por imagem , Diagnóstico Diferencial , Endoscopia Gastrointestinal , Endossonografia , Mucosa Gástrica/diagnóstico por imagem , Mucosa Gástrica/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Baço/cirurgia , Esplenectomia , Neoplasias Gástricas/patologia , Tomografia Computadorizada de Emissão
4.
World J Gastroenterol ; 13(33): 4473-9, 2007 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-17724803

RESUMO

AIM: To investigate the role of angiopoietin (Ang) -1, -2 and -4 and its receptors, Tie-1 and -2, in the growth and differentiation of gastrointestinal stromal tumors (GISTs). METHODS: Thirty GISTs, seventeen leiomyomas and six schwannomas were examined by immunohistochemistry in this study. RESULTS: Ang-1, -2 and -4 proteins were expressed in the cytoplasm of tumor cells, and Tie-1 and -2 were expressed both in the cytoplasm and on the membrane of all tumors. Immunohistochemical staining revealed that 66.7% of GISTs (20 of 30), 76.5% of leiomyomas (13 of 17) and 83.3% of schwannomas (5 of 6) were positive for Ang-1. 83.3% of GISTs (25 of 30), 82.4% of leiomyomas (14 of 17) and 100% of schwannomas (6 of 6) were positive for Ang-2. 36.7% of GISTs (11 of 30), 58.8% of leiomyomas (10 of 17) and 83.3% of schwannomas (5 of 6) were positive for Ang-4. 60.0% of GISTs (18 of 30), 82.4% of leiomyomas and 100% of schwannomas (6 of 6) were positive for Tie-1. 10.0% of GISTs (3 of 30), 94.1% of leiomyomas (16 of 17) and 33.3% of schwannomas (2 of 6) were positive for Tie-2. Tie-2 expression was statistically different between GISTs and leiomyomas (P < 0.001). However, there was no correlation between expression of angiopoietin pathway components and clinical risk categories. CONCLUSION: Our results suggest that the angiopoietin pathway plays an important role in the differentiation of GISTs, leiomyomas and schwannomas.


Assuntos
Angiopoietina-1/análise , Angiopoietina-2/análise , Angiopoietinas/análise , Tumores do Estroma Gastrointestinal/química , Leiomioma/química , Neurilemoma/química , Receptor de TIE-1/análise , Receptor TIE-2/análise , Neoplasias Gastrointestinais/química , Neoplasias Gastrointestinais/classificação , Neoplasias Gastrointestinais/patologia , Tumores do Estroma Gastrointestinal/patologia , Trato Gastrointestinal/química , Trato Gastrointestinal/patologia , Humanos , Leiomioma/patologia , Neurilemoma/patologia , Transdução de Sinais , Estatística como Assunto
5.
World J Gastroenterol ; 13(45): 6003-8, 2007 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-18023090

RESUMO

AIM: To investigate an association between N-acetyltransferase 2 (NAT2)-haplotypes/diplotypes and adverse effects in Japanese pulmonary tuberculosis patients. METHODS: We studied 100 patients with pulmonary TB treated with anti-TB drugs including INH. The frequencies and distributions of single nucleotide polymorphisms, haplotypes, and diplotypes of NAT2 were determined by the PCR-restriction fragment length polymorphism method, and the results were compared between TB patients with and without adverse effect, using multivariate logistic regression analysis. RESULTS: Statistical analysis revealed that the frequency of a variant haplotype, NAT2 6A, was significantly increased in TB patients with hepatotoxicity, compared with those without hepatotoxicity [P = 0.001, odds ratio (OR) = 3.535]. By contrast, the frequency of a wild-type (major) haplotype, "NAT2 4", was significantly lower in TB patients with hepatotoxicity than those without hepatotoxicity (P < 0.001, OR = 0.265). There was no association between NAT2-haplotypes and skin rash or eosinophilia. CONCLUSION: The present study shows that NAT2 is one of the determinants of anti-TB drug-induced hepatotoxicity. Moreover, the haplotypes, NAT2 4 and NAT2 6A, are useful new biomarkers for predicting anti-TB drug-induced hepatotoxicity.


Assuntos
Antituberculosos/efeitos adversos , Arilamina N-Acetiltransferase/genética , Doença Hepática Induzida por Substâncias e Drogas/genética , Tuberculose/tratamento farmacológico , Adulto , Idoso , Idoso de 80 Anos ou mais , Povo Asiático , Feminino , Haplótipos , Humanos , Japão , Masculino , Pessoa de Meia-Idade , Polimorfismo de Fragmento de Restrição , Polimorfismo de Nucleotídeo Único
6.
World J Gastroenterol ; 12(35): 5687-91, 2006 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-17007023

RESUMO

AIM: To investigate the role that the hedgehog (Hh) signaling pathway, which includes sonic hedgehog (Shh), Patched (Ptc), Smoothened (Smo) and Gli-1, plays in human gastrointestinal stromal tumors (GISTs). METHODS: Surgically resected specimens from patients with GISTs, leiomyomas and schwannomas were examined by immunohistochemical staining for aberrant expression of hedgehog signaling components, Shh, Ptc, Smo and Gli-1, respectively. RESULTS: In GISTs, 58.1% (18 of 31), 77.4% (24 of 31), 80.6% (25 of 31) and 58.1% (18 of 31) of the specimens stained positive for Shh, Ptc, Smo and Gli-1, respectively. In leiomyomas, 92.3% (12 of 13), 92.3% (12 of 13), 69.2% (9 of 13) and 92.3% (12 of 13) stained positive for Shh, Ptc, Smo and Gli-1, respectively. In schwannomas, 83.3% (5 of 6), 83.3% (5 of 6), 83.3% (5 of 6) and 100% (6 of 6) stained positive for Shh, Ptc, Smo and Gli-1, respectively. Immunohistochemistry revealed that the expressions of Shh and Gli-1 were significantly higher in leiomyomas than in GISTs (P < 0.05, respectively). Shh expression strongly correlated with the grade of tumor risk category and with tumor size (P < 0.05, respectively). However, the expressions of Ptc and Smo did not correlate with histopathological differentiation. CONCLUSION: These results suggest that the Hh signaling pathway may play an important role in myogenic differentiation and the malignant potential of human intestinal stromal tumors.


Assuntos
Tumores do Estroma Gastrointestinal/metabolismo , Proteínas Hedgehog/metabolismo , Neoplasias Intestinais/metabolismo , Receptores de Superfície Celular/metabolismo , Receptores Acoplados a Proteínas G/metabolismo , Fatores de Transcrição/metabolismo , Transformação Celular Neoplásica , Fator de Crescimento Epidérmico/genética , Fator de Crescimento Epidérmico/metabolismo , Tumores do Estroma Gastrointestinal/diagnóstico , Tumores do Estroma Gastrointestinal/genética , Tumores do Estroma Gastrointestinal/patologia , Regulação Neoplásica da Expressão Gênica/genética , Proteínas Hedgehog/genética , Humanos , Neoplasias Intestinais/diagnóstico , Neoplasias Intestinais/genética , Neoplasias Intestinais/patologia , Leiomioma/diagnóstico , Leiomioma/genética , Leiomioma/metabolismo , Leiomioma/patologia , Neurilemoma/diagnóstico , Neurilemoma/genética , Neurilemoma/metabolismo , Neurilemoma/patologia , Receptores Patched , Prognóstico , Proteínas Tirosina Quinases/genética , Proteínas Tirosina Quinases/metabolismo , Receptores de Superfície Celular/genética , Receptores Acoplados a Proteínas G/genética , Transdução de Sinais/genética , Receptor Smoothened , Fatores de Transcrição/genética , Proteína GLI1 em Dedos de Zinco
7.
World J Gastroenterol ; 12(11): 1743-6, 2006 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-16586544

RESUMO

AIM: Gastrointestinal stromal tumors (GISTs) are rare. GISTs differ from other mesenchymal tumors of the gastrointestinal tract (e.g. leiomyomas and schwannomas). The purpose of this study was to investigate the role of Ets-1 in the growth and differentiation of GISTs. METHODS: Twenty-eight GISTs, nine leiomyomas and six schwannomas were examined by immunohistochemical staining method for Ets-1 in this study. Specimens were selected from surgical pathology archival tissues at Nagasaki University Hospital. RESULTS: Ets-1 protein was expressed in the cytoplasm of cells in all of these tumors. Immunohistochemical staining revealed that 27 GISTs (96.4%), six leiomyomas (66.7%), and five schwannomas (83.3%) were positive for Ets-1. Ets-1 expression was statistically different between GISTs and leiomyomas (P<0.005). However, there was no correlation between Ets-1 expression and clinical risk categories. CONCLUSION: Ets-1 plays an important role in the growth and differentiation of GISTs, leiomyomas and schwannomas.


Assuntos
Neoplasias Gastrointestinais/metabolismo , Tumores do Estroma Gastrointestinal/metabolismo , Leiomioma/metabolismo , Neurilemoma/metabolismo , Proteína Proto-Oncogênica c-ets-1/metabolismo , Biomarcadores Tumorais/metabolismo , Proliferação de Células , Transformação Celular Neoplásica , Neoplasias Gastrointestinais/patologia , Tumores do Estroma Gastrointestinal/patologia , Humanos , Imuno-Histoquímica , Leiomioma/patologia , Neurilemoma/patologia
8.
World J Gastroenterol ; 12(38): 6182-7, 2006 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-17036392

RESUMO

AIM: To investigate the role of vascular endothelial growth factor (VEGF) and its receptors VEGFR-1 and 2 in the growth and differentiation of gastrointestinal stromal tumors (GISTs). METHODS: Thirty-three GISTs, 15 leiomyomas and 6 schwannomas were examined by immunohistochemistry in this study. RESULTS: VEGF protein was expressed in the cytoplasm of tumor cells, and VEGFR-1 and 2 were expressed both in the cytoplasm and on the membrane of all tumors. Immunohistochemical staining revealed that 26 GISTs (78.8%), 9 leiomyomas (60.0%) and 3 schwannomas (50.0%) were positive for VEGF; 24 GISTs (72.7%), 12 leiomyomas (80.0%) and 4 schwannomas (66.7%) were positive for VEGFR-1; 30 GISTs (90.9%), 5 leiomyomas (33.3%) and 4 schwannomas (66.7%) were positive for VEGFR-2. VEGFR-2 expression was statistically different between GISTs and leiomyomas (P < 0.0001). However, there was no correlation between the expression of VEGF pathway componenets and the clinical risk categories. CONCLUSION: Our results suggest that the VEGF pathway may play an important role in the differentiation of GISTs, leiomyomas and schwannomas.


Assuntos
Neoplasias Gastrointestinais/fisiopatologia , Tumores do Estroma Gastrointestinal/fisiopatologia , Leiomioma/fisiopatologia , Neurilemoma/fisiopatologia , Fator A de Crescimento do Endotélio Vascular/fisiologia , Receptor 1 de Fatores de Crescimento do Endotélio Vascular/fisiologia , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/fisiologia , Proliferação de Células , Regulação Neoplásica da Expressão Gênica , Humanos
9.
World J Gastroenterol ; 11(12): 1793-7, 2005 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-15793866

RESUMO

AIM: Interleukin 8 (IL-8) mediates neutrophil trafficking via its receptors. Recent studies have shown that IL-8 is likely involved in the development and progression of erosive reflux esophagitis (RE), yet little is known about the two distinct receptors, CXC receptor (CXCR)-1 and -2. The purpose of this study was to determine CXCR-1 and -2 messenger RNA expression levels in RE. METHODS: We studied 26 patients with RE and 15 asymptomatic controls. Paired biopsy samples were taken from the esophagus 3 cm above the gastroesophageal junction; one biopsy was snap frozen for measurement of CXCR-1 and -2 mRNA levels by semiquantitative reverse transcriptase polymerase chain reaction (RT-PCR), and another was formalin-fixed for histopathological evaluation. We also examined the association of the expression levels of CXCR-1 and -2 mRNA with histopathological hallmarks of RE. RESULTS: The relative CXCR-1 and -2 mRNA expression levels were rather decreased in esophageal mucosa of patients with RE, compared to those in normal esophagus of controls. There were no significant difference in the relative mRNA expression levels of CXCR-1 and -2 among endoscopic grades of RE based on the Los Angeles classification. Each histopathological hallmark of GERD was not associated with the expression levels of CXCR-1 and -2 mRNA. CONCLUSION: Apart from overexpression of IL-8, the relative expression levels of CXCR-1 and -2 mRNA were rather lower than expected in the affected esophageal mucosa of patients with RE.


Assuntos
Esofagite Péptica/fisiopatologia , Esôfago/metabolismo , Receptores de Interleucina-8A/genética , Receptores de Interleucina-8B/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Biópsia , Esofagite Péptica/metabolismo , Esofagite Péptica/patologia , Esôfago/patologia , Feminino , Expressão Gênica , Humanos , Masculino , Pessoa de Meia-Idade , Mucosa/metabolismo , Mucosa/patologia , RNA Mensageiro/análise , Receptores de Interleucina-8A/metabolismo , Receptores de Interleucina-8B/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa
10.
World J Gastroenterol ; 11(11): 1629-33, 2005 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-15786539

RESUMO

AIM: The mucoprotective agents, sofalcone and polaprezinc have anti-Helicobacter pylori (H pylori) activities. We determined the therapeutic effects of sofalcone and polaprezinc when combined with rabeprazole, amoxicillin and clarithromycin for Helicobacter pylori infection. METHODS: One hundred and sixty-five consecutive outpatients with peptic ulcer and H pylori infection were randomly assigned to one of the following three groups and medicated for 7 d. Group A: triple therapy with rabeprazole (10 mg twice daily), clarithromycin (200 mg twice daily) and amoxicillin (750 mg twice daily). Group B: sofalcone (100 mg thrice daily) plus the triple therapy. Group C: polaprezinc (150 mg twice daily) plus the triple therapy. Eradication was considered successful if (13)C-urea breath test was negative at least 4 wk after cessation of eradication regimens or successive famotidine in the cases of active peptic ulcer. RESULTS: On intention-to-treat basis, H pylori cure was achieved in 43 of 55 (78.2%) patients, 47 of 54 (87.0%) and 45 of 56 (80.4%) for the groups A, B and C respectively. Using per protocol analysis, the eradication rates were 81.1% (43/53), 94.0% (47/50) and 84.9% (45/53) respectively. There was a significant difference in the cure rates between group A and B. Adverse events occurred in 10, 12 and 11 patients, from groups A, B and C respectively, but the events were generally mild. CONCLUSION: The addition of sofalcone, but not polaprezinc, significantly increased the cure rate of H pylori infection when combined with the rabeprazole-amoxicillin-clarithromycin regimen.


Assuntos
Amoxicilina/administração & dosagem , Antibacterianos/administração & dosagem , Antiulcerosos/administração & dosagem , Chalcona/análogos & derivados , Chalcona/administração & dosagem , Infecções por Helicobacter/tratamento farmacológico , Helicobacter pylori , Omeprazol/análogos & derivados , 2-Piridinilmetilsulfinilbenzimidazóis , Adulto , Idoso , Benzimidazóis/administração & dosagem , Chalconas , Claritromicina/administração & dosagem , Quimioterapia Combinada , Feminino , Mucosa Gástrica/efeitos dos fármacos , Mucosa Gástrica/microbiologia , Humanos , Masculino , Pessoa de Meia-Idade , Omeprazol/administração & dosagem , Úlcera Péptica/tratamento farmacológico , Úlcera Péptica/microbiologia , Rabeprazol
11.
World J Gastroenterol ; 11(11): 1644-8, 2005 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-15786542

RESUMO

AIM: Ghrelin, an endogenous ligand for growth hormone secretagogue receptor, influences appetite, energy balance, gastric motility and acid secretion. The stomach is the main source of circulating ghrelin. There are inconsistent reports on the influence of Helicobacter pylori (H pylori) infection on circulating ghrelin levels. We sought to elucidate the relationship between ghrelin and various peptides in plasma, with special reference to H pylori. METHODS: Plasma ghrelin levels were measured by radioimmunoassay in 89 subjects who were referred for upper gastrointestinal endoscopy, consisting of 42 H pylori infected and 47 uninfected ones. Plasma gastrin, somatostatin, leptin, insulin-like growth hormone 1 (IGF-1) and chromogranin A concentrations were also measured. Twelve patients were treated with anti- H pylori regimen. RESULTS: Ghrelin circulating levels were greatly decreased in H pylori-positive than negative individuals (194.2+/-90.2 fmol/mL and 250.4+/-84.1 respectively, P<0.05), but did not significantly alter following the cure of infection (176.5+/-79.5 vs 191.3+/-120.4). There was a significant negative correlation between circulating ghrelin and leptin levels, as well as body mass index, for the whole and uninfected population, but not in H pylori-infected patients. Plasma ghrelin concentrations correlated positively with IGF-1 in H pylori-negative group and negatively with chromogranin A in the infected group. There were no significant correlations among circulating levels of ghrelin, gastrin and somatostatin irrespective of H pylori status. CONCLUSION: H pylori infection influences plasma ghrelin dynamics and its interaction with diverse bioactive peptides involved in energy balance, growth and neuroendocrine function.


Assuntos
Infecções por Helicobacter/metabolismo , Helicobacter pylori , Sistemas Neurossecretores/metabolismo , Hormônios Peptídicos/sangue , Adulto , Idoso , Metabolismo Energético , Feminino , Gastrinas/sangue , Grelina , Humanos , Fator de Crescimento Insulin-Like I/metabolismo , Leptina/sangue , Masculino , Pessoa de Meia-Idade
12.
World J Gastroenterol ; 11(10): 1567-9, 2005 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-15770740

RESUMO

A 21-year-old woman with complaints of hematochezia was diagnosed as having Cowden's disease (CD), an autosomal dominant condition characterized by multiple hamartomas, since facial papules and gingival papillomas were identified. On endoscopy, multiple hyperplastic polyps were seen in the rectum and left-side colon. There were also esophageal glycogenic acanthosis and hyperplastic polyposis in the antrum accompanied by Helicobacter pylori-related gastritis. Although gastric hyperplastic polyposis had by no means regressed with unsuccessful first-line eradication therapy for H pylori, following cure of the infection with salvage therapy consisting of rabeprazole, amoxicillin and metronidazole, the polyposis lesions almost disappeared. Follow-up gastroscopy 2 and 3 years after cessation of the second-line eradication therapy revealed almost complete regression of the polyposis lesions with no evidence of H pylori infection. We recommend eradication treatment for CD patients with gastric hyperplastic polyps and the infection, as the occurrence of gastric carcinoma among hyperplastic polyps has been described.


Assuntos
Antibacterianos , Quimioterapia Combinada/uso terapêutico , Síndrome do Hamartoma Múltiplo/complicações , Infecções por Helicobacter/complicações , Helicobacter pylori , Pólipos/etiologia , Pólipos/microbiologia , Gastropatias/etiologia , Adulto , Feminino , Infecções por Helicobacter/tratamento farmacológico , Humanos , Hiperplasia , Pólipos/patologia , Gastropatias/microbiologia
13.
World J Gastroenterol ; 11(7): 964-9, 2005 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-15742397

RESUMO

AIM: There is strong evidence that tyrosine kinases are involved in the regulation of tumor progression, cellular growth and differentiation. Recently, many kinds of tyrosine kinase receptors have been reported, among them Tie-1 and Tie-2 receptors constitute a major class. Angiopoietin (Ang)-1 is known as a ligand of Tie-2 tyrosine kinase receptor. The objective of this study was to establish a comprehensive Tie-1 and Tie-2 and Ang-1, 2 and 4 expression profile in human colorectal adenocarcinomas. METHODS: We examined 96 cases of surgically resected human colorectal adenocarcinoma by immunohistochemistry and investigated the statistical correlation between the expressions of Ties and Angs and clinicopathological factors. RESULTS: Among the 96 cases of adenocarcinoma, 87 (90.6%), 92 (95.8%), 83 (86.5%), 89 (92.7%), and 76 cases (79.2%) showed positive staining in the cytoplasm of carcinoma cells for the Tie-1 and Tie-2 and Ang-1, 2 and 4 proteins, respectively. Histologically, the expressions of Ties and Angs were variable. The expressions of Ties and Angs were correlated with several clinicopathological factors, but did not correlate with the presence of lymph node metastasis. Ties and Angs were highly expressed in human colorectal adenocarcinoma cells. CONCLUSION: These findings suggest that the Tie-Ang receptor-ligand complex is one of the factors involved in the cellular differentiation and progression of human colorectal adenocarcinoma.


Assuntos
Adenocarcinoma/metabolismo , Angiopoietina-1/metabolismo , Angiopoietina-2/metabolismo , Neoplasias Colorretais/metabolismo , Receptor de TIE-1/metabolismo , Receptor TIE-2/metabolismo , Adenocarcinoma/patologia , Angiopoietinas/metabolismo , Diferenciação Celular , Neoplasias Colorretais/patologia , Progressão da Doença , Humanos , Imuno-Histoquímica , Ligantes
14.
World J Gastroenterol ; 11(1): 27-30, 2005 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-15609391

RESUMO

AIM: To investigate the incidence of Epstein-Barr virus-associated gastric cancer (EBV-GC) in Kazakhstan and to compare it with that in Russia, Western and Asian countries in order to evaluate the significance of epidemiopathologic and ethnic factors. METHODS: In situ hybridization (ISH) of EBV-encoded small RNA-1 (EBER-1) was used to identify the presence of EBER-1 signal in 139 formalin-fixed and paraffin-embedded GC tissues from Kazakhstan. RESULTS: EBER-1 expression was observed in the nuclei of 10% of the cases of GC (14/139), but not in the surrounding normal mucosa. The incidence of the diffuse type of EBV-GC was significantly higher in Kazakhstan (14%, 13/91) than that of the intestinal type (2%, 1/48). Furthermore, the incidence was significantly higher in males (14%, 12/89) than in females (3.7%, 2/53) from all countries. The overall incidence of EBV-GC increased from 6.7% in Asian countries to 8.7% in Russia, 10.1% in Kazakhstan and 16% in Western countries. CONCLUSION: Geographical differences in the incidence of EBV-GC may reflect the epidemiologic factors and/or dietary habits independent of histological type and sex.


Assuntos
Adenocarcinoma Mucinoso/etnologia , Carcinoma de Células em Anel de Sinete/etnologia , Infecções por Vírus Epstein-Barr/etnologia , Herpesvirus Humano 4/isolamento & purificação , Neoplasias Gástricas/etnologia , Adenocarcinoma Mucinoso/patologia , Adulto , Distribuição por Idade , Povo Asiático/estatística & dados numéricos , Carcinoma de Células em Anel de Sinete/patologia , Infecções por Vírus Epstein-Barr/patologia , Feminino , Herpesvirus Humano 4/genética , Humanos , Incidência , Cazaquistão/epidemiologia , Masculino , Pessoa de Meia-Idade , Prognóstico , RNA Viral/análise , Distribuição por Sexo , Neoplasias Gástricas/patologia , População Branca/estatística & dados numéricos
15.
World J Gastroenterol ; 11(1): 99-103, 2005 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-15609405

RESUMO

AIM: To determine the concentration of alpha- and beta-defensins in gastric juice of patients with various gastroduodenal diseases. METHODS: Concentrations of human neutrophil peptides (HNPs) 1-3, the major forms of alpha-defensins, and human beta-defensin (HBD)-1 and HBD-2 were measured by radioimmunoassay in plasma and gastric juice of 84 subjects, consisting of 54 Helicobacter pylori-infected and 30 uninfected subjects. They included 33 patients with chronic gastritis (CG), 12 with gastric ulcer (GU), 11 with duodenal ulcer (DU), 11 with benign gastric polyp (BGP) and 16 with normal mucosa (N group) on upper endoscopy. Plasma pepsinogen I and II levels, biomarkers for gastric mucosal inflammation and atrophy, were also measured. RESULTS: Gastric juice HNPs 1-3 levels in patients with CG, GU and BGP were significantly higher than those in patients with DU and N. Gastric juice HBD-2 concentrations in patients with CG and GU were significantly higher than those in the N group, but were significantly lower in DU patients than in GU patients. Gastric juice HBD-1 levels and plasma levels of these peptides were similar in the patient groups. Concentrations of gastric juice HNPs 1-3 and HBD-2 of in H pylori-infected patients were significantly different from those in uninfected subjects. HNPs 1-3 concentrations in gastric juice correlated negatively with plasma pepsinogen I levels and I/II ratios. HBD-2 levels in gastric juice correlated positively and negatively with plasma pepsinogen II concentrations and I/II ratios, respectively. CONCLUSION: HNPs 1-3 and HBD-2 levels in gastric juice are diverse among various gastrointestinal diseases, reflecting the inflammatory and atrophic events of the background gastric mucosa affected by H pylori.


Assuntos
Duodenopatias/metabolismo , Suco Gástrico/metabolismo , Gastropatias/metabolismo , alfa-Defensinas/metabolismo , beta-Defensinas/metabolismo , Gastrinas/sangue , Infecções por Helicobacter/metabolismo , Helicobacter pylori , Humanos , Pepsinogênio A/sangue
16.
World J Gastroenterol ; 11(5): 695-9, 2005 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-15655824

RESUMO

AIM: To determine the concentrations of leptin in plasma and gastric fundic mucosa in humans, with reference to Helicobacter pylori (H pylori) infection, and their association with gastric mucosal levels of interleukin (IL)-1beta, IL-6 and IL-8. METHODS: Plasma leptin concentrations were determined in 135 outpatients with non-ulcer dyspepsia, consisting of 95 H pylori-infected and 40 uninfected subjects, and 13 patients before and after cure of the infection with anti-H pylori regimen. Using biopsy samples that were endoscopically obtained from the middle corpus along the greater curvature, gastric leptin contents were measured by radioimmunoassay and the mucosal concentrations of IL-1beta, IL-6 and IL-8 were measured by enzyme linked immunosorbent assay. We also analysed the expression of leptin in the fundic mucosa by reverse transcriptase-polymerase chain reaction (RT-PCR) and immunohistochemistry. RESULTS: The mucosal levels of leptin in the fundic mucosa of H pylori-infected patients were significantly higher than those of uninfected patients. The amount of gastric leptin correlated positively with the mucosal levels of IL-1beta and IL-6, but not IL-8. Circulating leptin correlated with body mass index, but not with H pylori status, and there was no change in plasma leptin levels following cure of the infection. Leptin immunoreactive cells were noted in the lower half of the fundic glands, and its expression of messenger ribonucleic acid in the oxyntic mucosa was detected by RT-PCR. CONCLUSION: Leptin production is enhanced in H pylori-infected gastric mucosa. Gastric leptin may be involved in immune and inflammatory response during H pylori infection, through interaction with proinflammatory cytokines.


Assuntos
Fundo Gástrico/metabolismo , Mucosa Gástrica/metabolismo , Infecções por Helicobacter/metabolismo , Helicobacter pylori , Leptina/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Fundo Gástrico/imunologia , Mucosa Gástrica/imunologia , Gastrite/imunologia , Gastrite/metabolismo , Gastrite/microbiologia , Infecções por Helicobacter/imunologia , Infecções por Helicobacter/fisiopatologia , Humanos , Interleucina-1/metabolismo , Interleucina-6/metabolismo , Interleucina-8/metabolismo , Leptina/sangue , Masculino , Pessoa de Meia-Idade , RNA Mensageiro/análise
17.
World J Gastroenterol ; 11(29): 4505-10, 2005 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-16052679

RESUMO

AIM: To produce an antibody against rat eosinophil cationic protein (ECP) and to examine the effects of the antibody in rats with dextran sulfate sodium (DSS)-induced colitis. METHODS: An antibody was raised against rat ECP. Rats were treated with 3% DSS in drinking water for 7 d and received the antibody or normal serum. The colons were examined histologically and correlated with clinical symptoms. Immunohistochemistry and Western blot analysis were estimated as a grade of inflammation. RESULTS: The ECP antibody stained the activated eosinophils around the injured crypts in the colonic mucosa. Antibody treatment reduced the severity of colonic ulceration and acute clinical symptoms (diarrhea and/or blood-stained stool). Body weight gain was significantly greater and the colon length was significantly longer in anti-ECP-treated rats than in normal serum-treated rats. Expression of ECP in activated eosinophils was associated with the presence of erosions and inflammation. The number of Ki-67-positive cells in the regenerated surface epithelium increased in anti-ECP-treated rats compared with normal serum-treated rats. Western blot analysis revealed reduced expression of macrophage migration inhibitory factor (MIF) in anti-ECP-treated rats. CONCLUSION: Our results indicate that treatment with ECP antibody, improved DSS-induced colitis in rats, possibly by increasing the regenerative activity of the colonic epithelium and downregulation of the immune response, and suggest that anti-ECP may promote intestinal wound healing in patients with ulcerative colitis (UC).


Assuntos
Anticorpos/farmacologia , Colite Ulcerativa/prevenção & controle , Colite Ulcerativa/terapia , Proteína Catiônica de Eosinófilo/imunologia , Imunoterapia/métodos , Sequência de Aminoácidos , Animais , Anticoagulantes , Colite Ulcerativa/induzido quimicamente , Sulfato de Dextrana , Proteína Catiônica de Eosinófilo/química , Masculino , Dados de Sequência Molecular , Ratos , Ratos Wistar
18.
World J Gastroenterol ; 11(27): 4188-93, 2005 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-16015687

RESUMO

AIM: To examine an association between the cytotoxic T-lymphocyte antigen 4 (CTLA4) gene that plays a role in downregulation of T-cell activation and inflammatory bowel disease consisting of ulcerative colitis (UC) and Crohn's disease (CD) in the Japanese. METHODS: We studied 108 patients with UC, 79 patients with CD, and 200 sex-matched healthy controls, with respect to three single nucleotide polymorphisms (SNPs) in CTLA4, such as C-318T in the promoter region, A+49G in exon 1 and G+6230A in the 3' untranslated region (3'-UTR) by a PCR-restriction fragment length polymorphism method, and to an (AT)(n) repeat polymorphism in 3'-UTR by fragment analysis with fluorescence-labeling on denaturing sequence gels. Frequency of alleles and genotypes and their distribution were compared statistically between patients and controls and among subgroups of patients, using chi (2) and Fisher exact tests. RESULTS: The frequency of "A/A" genotype at the G+6230A SNP site was statistically lower in UC patients than in controls (3.7% vs 11.0%, P = 0.047, odds ratio (OR) = 0.311). Moreover, the frequency of "G/G" genotype at the A+49G SNP site was significantly higher in CD patients with fistula (48.6%) than those without it (26.2%) (P = 0.0388, OR=2.67). CONCLUSION: The results suggest that CTLA4 located at 2q33 is a determinant of UC and responsible for fistula formation in CD in the Japanese.


Assuntos
Antígenos de Diferenciação/genética , Colite Ulcerativa/genética , Doença de Crohn/genética , Polimorfismo de Nucleotídeo Único , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Antígenos CD , Antígeno CTLA-4 , Feminino , Frequência do Gene , Genótipo , Humanos , Japão , Masculino , Pessoa de Meia-Idade
19.
World J Gastroenterol ; 11(31): 4782-7, 2005 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-16097044

RESUMO

AIM: Human beta-defensin (HBD)-1 and HBD-2 are endogenous antimicrobial peptides. Unlike HBD-1, the HBD-2 expression is augmented by Helicobacter pylori (H pylori). We sought to determine HBD-1 and HBD-2 concentrations in gastric juice during H pylori infection. METHODS: HBD-1 and HBD-2 concentrations were measured by radioimmunoassay in plasma and gastric juice of 49 H pylori-infected and 33 uninfected subjects and before and after anti-H pylori treatment in 13 patients with H pylori-associated gastritis. Interleukin (IL)-1beta and IL-8 concentrations in gastric juice were measured by enzyme-linked immunosorbent assay (ELISA). Histological grades of gastritis were determined using two biopsy specimens taken from the antrum and corpus. Reverse phase high performance liquid chromatography (RP-HPLC) was used to identify HBD-2. RESULTS: HBD-2 concentrations in gastric juice, but not in plasma, were significantly higher in H pylori-positive than -negative subjects, albeit the post-treatment levels were unchanged. Immunoreactivity for HBD-2 was exclusively identified in H pylori-infected mucosa by RP-HPLC. HBD-2 concentrations in gastric juice correlated with histological degree of neutrophil and mononuclear cell infiltration in the corpus. IL-1beta levels correlated with those of IL-8, but not HBD-2. Plasma and gastric juice HBD-1 concentrations were similar in H pylori-infected and uninfected subjects. CONCLUSION: Our results place the beta-defensins, especially HBD-2, in the front line of innate immune defence. Moreover, HBD-2 may be involved in the pathogenesis of H pylori-associated gastritis, possibly through its function as immune and inflammatory mediator.


Assuntos
Suco Gástrico/química , Infecções por Helicobacter/metabolismo , Helicobacter pylori , beta-Defensinas/metabolismo , Anti-Infecciosos/análise , Infecções por Helicobacter/patologia , Humanos , beta-Defensinas/sangue
20.
World J Gastroenterol ; 11(31): 4833-7, 2005 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-16097053

RESUMO

AIM: To investigate the frequency and distribution of N-acetyltransferase 2 (NAT2) and uridine 5'-diphosphate (UDP)-glucuronosyltransferase 1A7 (UGT1A7) genes in patients with ulcerative colitis (UC) and Crohn's disease (CD). METHODS: Frequencies and distributions of NAT2 and UGT1A7 SNPs as well as their haplotypes were investigated in 95 patients with UC, 60 patients with CD, and 200 gender-matched, unrelated, healthy, control volunteers by PCR-restriction fragment length polymorphism (RFLP), PCR-denaturing high-performance liquid chromatography (DHPLC), and direct DNA sequencing. RESULTS: Multiple logistic regression analysis revealed that the frequency of haplotype, NAT2*7B, significantly increased in CD patients, compared to that in controls (P = 0.0130, OR = 2.802, 95%CI = 1.243-6.316). However, there was no association between NAT2 haplotypes and UC, or between any UGT1A7 haplotypes and inflammatory bowel disease (IBD). CONCLUSION: It is likely that the NAT2 gene is one of the determinants for CD in Japanese. Alternatively, a new CD determinant may exist in the 8p22 region, where NAT2 is located.


Assuntos
Arilamina N-Acetiltransferase/genética , Colite Ulcerativa/enzimologia , Doença de Crohn/enzimologia , Doença de Crohn/genética , Polimorfismo de Nucleotídeo Único , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Frequência do Gene , Humanos , Pessoa de Meia-Idade , Valores de Referência
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