Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 29
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
Phys Rev Lett ; 115(16): 168301, 2015 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-26550905

RESUMO

The chain-folding mechanism and structure of semicrystalline polymers have long been controversial. Solid-state NMR was applied to determine the chain trajectory of (13)C CH3-labeled isotactic poly(1-butene) (iPB1) in form III chiral single crystals blended with nonlabeled iPB1 crystallized in dilute solutions under low supercooling. An advanced (13)C-(13)C double-quantum NMR technique probing the spatial proximity pattern of labeled (13)C nuclei revealed that the chains adopt a three-dimensional (3D) conformation in single crystals. The determined results indicate a two-step crystallization process of (i) cluster formation via self-folding in the precrystallization stage and (ii) deposition of the nanoclusters as a building block at the growth front in single crystals.

2.
J Dermatol ; 40(1): 2-14, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22900999

RESUMO

In 2010, the first Japanese edition of guidelines for the management of cutaneous lymphoma was published jointly by the Japanese Dermatological Association (JDA) and the Japanese Skin Cancer Society (JSCS) - Lymphoma Study Group. Because the guidelines were revised in 2011 based on the most recent data, we summarized the revised guidelines in English for two reasons: (i) to inform overseas clinicians about our way of managing common types of cutaneous lymphomas such as mycosis fungoides/Sézary syndrome; and (ii) to introduce Japanese guidelines for lymphomas peculiar to Asia, such as adult T-cell leukemia/lymphoma and extranodal natural killer/T-cell lymphoma, nasal type. References that provide scientific evidence for these guidelines have been selected by the JSCS - Lymphoma Study Group. These guidelines, together with the degrees of recommendation, have been made in the context of limited medical treatment resources, and standard medical practice within the framework of the Japanese National Health Insurance system.


Assuntos
Linfoma Cutâneo de Células T/terapia , Neoplasias Cutâneas/terapia , Humanos , Japão , Linfoma Cutâneo de Células T/patologia , Estadiamento de Neoplasias , Neoplasias Cutâneas/patologia , Sociedades Médicas
3.
Hum Pathol ; 44(5): 734-42, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23084584

RESUMO

Upper gastrointestinal neoplasia in the esophagus, stomach, and pancreas is associated with the formation of preneoplastic metaplasias. We have previously reported the up-regulation of human epididymis protein 4 (HE4) in all metaplasias in the stomach of humans and mice. We have now sought to evaluate the expression of HE4 in metaplasias/preneoplastic precursors and cancers of the human stomach, pancreas, and esophagus. Tissue microarrays for gastric cancers, pancreatic cancers, and esophageal adenocarcinoma were stained with antibodies against HE4. Immunostaining was quantified by digital imaging, and the results were evaluated to assess the expression in metaplasias, the expression in cancer pathological subtypes, and the effects of expression on survival in patients with cancer. In patients with gastric cancer from Korea, HE4 was detected in 74% of intestinal and 90% of diffuse cancers, whereas in a gastric cancer cohort from Johns Hopkins, HE4 was detected in 74% of intestinal-type and 92% of diffuse cancers. Nevertheless, in both cohorts, there was no impact of HE4 expression on overall survival. In the esophagus, we observed the expression of HE4 in scattered endocrine cells within Barrett esophagus samples, but Barrett columnar metaplasias and HE4 were detected in only 2% of esophageal adenocarcinomas. Finally, in the pancreas, HE4 expression was not observed in pancreatic intraepithelial neoplasia lesions, but 46.8% of pancreatic adenocarcinomas expressed HE4. Still, we did not observe any influence of HE4 expression on survival. The results suggest that HE4 is up-regulated during gastric and pancreatic carcinogenesis.


Assuntos
Adenocarcinoma/genética , Biomarcadores Tumorais/metabolismo , Neoplasias Pancreáticas/genética , Proteínas/metabolismo , Neoplasias Gástricas/genética , Adenocarcinoma/patologia , Biomarcadores Tumorais/genética , Neoplasias Esofágicas/genética , Neoplasias Esofágicas/patologia , Esôfago/metabolismo , Mucosa Gástrica/metabolismo , Humanos , Metaplasia/metabolismo , Pâncreas/metabolismo , Neoplasias Pancreáticas/patologia , Neoplasias Gástricas/mortalidade , Neoplasias Gástricas/patologia , Regulação para Cima , Proteína 2 do Domínio Central WAP de Quatro Dissulfetos
4.
Dig Dis Sci ; 54(8): 1625-35, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19507031

RESUMO

Spasmolytic polypeptide (SP/TFF2)-expressing metaplasia (SPEM) is induced by oxyntic atrophy and is known as a precancerous or paracancerous lesion. We seek to determine whether the gastrin receptor or H(2) histamine receptor influence the development of SPEM. DMP-777 was administered to gastrin receptor and/or H(2) receptor-deficient mice and wild-type mice. Gastric mucosal lineage changes were analyzed. The mucosa from double knockout mice and H(2) receptor knockout mice contained elevated numbers of dual TFF2 and intrinsic factor immunoreactive cells even before DMP-777 treatment. All genotypes of mice showed SPEM after 7-day treatment. In all types of knockout mice, the number of TFF2 immunoreactive cells remained elevated after cessation of treatment. The H(2) receptor and gastrin receptor do not affect emergence of SPEM. However, it is suggested that the absence of H(2) receptor signaling causes a delay in the maturation of chief cells from mucous neck cells.


Assuntos
Linhagem da Célula , Mucosa Gástrica/citologia , Células Parietais Gástricas/patologia , Receptor de Colecistocinina B/metabolismo , Receptores Histamínicos H2/metabolismo , Animais , Atrofia/induzido quimicamente , Atrofia/patologia , Azetidinas/efeitos adversos , Azetidinas/farmacologia , Diferenciação Celular/efeitos dos fármacos , Linhagem da Célula/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Mucosa Gástrica/metabolismo , Gastrinas/sangue , Fator Intrínseco/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Mucinas/metabolismo , Proteínas Musculares/metabolismo , Células Parietais Gástricas/metabolismo , Peptídeos/metabolismo , Piperazinas/efeitos adversos , Piperazinas/farmacologia , Receptor de Colecistocinina B/genética , Receptores Histamínicos H2/genética , Fator Trefoil-2
5.
Anal Sci ; 25(5): 723-6, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-19430160

RESUMO

Anionic surfactant solutions of sodium dodecylbenzenesulfonate (SDBS) and sodium dodecylsulfate (SDS) separate into two phases through cooling of the solution and the addition of salts. Thiourea (TU) reacts with many metals to form cationic complexes of [M(TU)(n)](m+); some of them extract into the SDBS phase. The separation was examined for lead and tin in commercially purchased solders. More than 95% lead was extracted into the SDBS phase, while tin remained in the aqueous phase. An abnormal decrease in extractability was observed for the [M(TU)(n)](m+) of noble metal complexes at low metal concentrations. The surfactant phases of SDBS and SDS were confirmed as lamellar structures using small angle X-ray scattering (SAXS), and the stability and rigidity of this structure influenced the extractability of the [Au(TU)(n)](3+) complex. The separation of gold(III) and palladium(II) was examined for the SDS system.

6.
Am J Physiol Gastrointest Liver Physiol ; 296(6): G1211-20, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19359424

RESUMO

The orderly differentiation of cell lineages within gastric glands is regulated by a complicated interplay of local mucosal growth factors and hormones. Histamine secreted from enterochromaffin-like cells plays an important role in not only stimulated gastric acid secretion but also coordination of intramucosal growth and lineage differentiation. We have examined histidine-decarboxylase (HDC)-deficient mice, which lack endogenous histamine synthesis, to evaluate the influence of histamine on differentiation of fundic mucosal lineages and the development of metaplasia following induction of acute oxyntic atrophy. Stomachs from HDC-deficient mice and wild-type mice were evaluated at 8 wk and 12 mo of age. DMP-777 was administrated orally to 6-wk-old mice for 1 to 14 days. Sections of gastric mucosa were stained with antibodies against Mist1, intrinsic factor, H/K-ATPase, trefoil factor 2 (TFF2), chromogranin A, and Ext1 and for the cell cycle marker phospho-histone H3. HDC-deficient mice at 8 wk of age demonstrated a prominent increase in chief cells expressing Mist1 and intrinsic factor. Importantly Mist1-positive mature chief cells were present in the midgland region as well as at the bases of fundic glands, indicating a premature differentiation of chief cells. Mice dually deficient for both HDC and gastrin showed a normal distribution of chief cells in fundic glands. Treatment of HDC-deficient mice with DMP-777 led to loss of parietal cells and an accelerated and exaggerated emergence of mucous cell metaplasia with the presence of dual intrinsic factor and TFF2-expressing cells throughout the gland length, indicative of the emergence of spasmolytic polypeptide-expressing metaplasia (SPEM) from chief cells. These findings indicate that histamine, in concert with gastrin, regulates the appropriate differentiation of chief cells from mucous neck cells as they migrate toward the bases of fundic glands. Nevertheless, histamine is not required for emergence of SPEM following acute oxyntic atrophy.


Assuntos
Diferenciação Celular , Celulas Principais Gástricas/patologia , Histamina/deficiência , Fatores Etários , Animais , Azetidinas/farmacologia , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Contagem de Células , Diferenciação Celular/efeitos dos fármacos , Celulas Principais Gástricas/metabolismo , Cromogranina A/metabolismo , Celulas Tipo Enterocromafim/metabolismo , Celulas Tipo Enterocromafim/patologia , Inibidores Enzimáticos/farmacologia , Fundo Gástrico/patologia , Mucosa Gástrica/patologia , Gastrinas/genética , Histidina Descarboxilase/deficiência , Histidina Descarboxilase/genética , Hiperplasia/patologia , Hipertrofia/patologia , Fator Intrínseco/metabolismo , Metaplasia/induzido quimicamente , Metaplasia/patologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Knockout , Mucinas/metabolismo , Proteínas Musculares/metabolismo , N-Acetilglucosaminiltransferases/metabolismo , Células Parietais Gástricas/patologia , Peptídeos/metabolismo , Piperazinas/farmacologia , Fator Trefoil-2
7.
Asian Pac J Cancer Prev ; 9(1): 25-30, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18439067

RESUMO

The relation between Helicobacter pylori (Hp) eradication and prevention of stomach carcinoid development has hitherto remained unclear. We therefore examined this problem using an Hp-infected and Hp-eradicated Mongolian gerbil (MG) model. Enterochromaffin-like (ECL) lesions (hyperplasia/dysplasia and carcinoid) were histopathologically evaluated in the glandular stomachs of Hp-infected and Hp-eradicated MGs. In addition, serum gastrin levels were analyzed. Hp infection induced significant increase in the development of ECL lesions in the glandular stomach, as well as serum gastrin levels as compared with non-infected MGs, while Hp eradication was associated with significant alleviation. The development of ECL lesions in the glandular stomach strongly correlated with titers of anti-Hp antibodies and serum gastrin levels in MGs. In conclusion, Hp infection induces carcinoid development, and Hp eradication prevents its occurrence in the glandular MG stomach, this being strongly linked with reduction in serum gastrin levels.


Assuntos
Tumor Carcinoide/etiologia , Infecções por Helicobacter/complicações , Infecções por Helicobacter/tratamento farmacológico , Helicobacter pylori/patogenicidade , Neoplasias Gástricas/etiologia , Animais , Antibacterianos/farmacologia , Tumor Carcinoide/patologia , Tumor Carcinoide/prevenção & controle , Celulas Tipo Enterocromafim/patologia , Gastrinas/sangue , Gerbillinae , Helicobacter pylori/efeitos dos fármacos , Hiperplasia , Masculino , Neoplasias Gástricas/patologia , Neoplasias Gástricas/prevenção & controle
8.
Gastroenterology ; 134(2): 511-22, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18242217

RESUMO

BACKGROUND & AIMS: Loss of gastric parietal cells is a critical precursor to gastric metaplasia and neoplasia. However, the origin of metaplasia remains obscure. Acute parietal cell loss in gastrin-deficient mice treated with DMP-777 leads to the rapid emergence of spasmolytic polypeptide/trefoil factor family 2 (TFF2)-expressing metaplasia (SPEM) from the bases of fundic glands. We now sought to characterize more definitively the pathway for emergence of SPEM. METHODS: Emerging SPEM lineages in gastrin-deficient mice treated with DMP-777 were examined for immunolocalization of TFF2, intrinsic factor, and Mist1, and morphologically with electron microscopy. Emerging SPEM was isolated with laser-capture microdissection and RNA was analyzed using gene microarrays. Immunohistochemistry in mouse and human samples was used to confirm up-regulated transcripts. RESULTS: DMP-777-induced SPEM was immunoreactive for TFF2 and the differentiated chief cell markers, Mist1 and intrinsic factor, suggesting that SPEM derived from transdifferentiation of chief cells. Microarray analysis of microdissected SPEM lineages induced by DMP-777 showed up-regulation of transcripts associated with G1/S cell-cycle transition including minichromosome maintenance deficient proteins, as well as a number of secreted factors, including human epididymis 4 (HE4). HE4, which was absent in the normal stomach, was expressed in SPEM of human and mouse and in intestinal metaplasia and gastric cancer in human beings. CONCLUSIONS: Although traditionally metaplasia was thought to originate from normal mucosal progenitor cells, these studies indicate that SPEM evolves through either transdifferentiation of chief cells or activation of a basal cryptic progenitor. In addition, induction of metaplasia elicits the expression of secreted factors, such as HE4, relevant to gastric preneoplasia.


Assuntos
Fundo Gástrico/metabolismo , Fundo Gástrico/patologia , Mucosa Gástrica/metabolismo , Mucosa Gástrica/patologia , Mucinas/metabolismo , Proteínas Musculares/metabolismo , Células Parietais Gástricas/patologia , Peptídeos/metabolismo , Animais , Atrofia , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Proteínas de Transporte/metabolismo , Proteínas de Ciclo Celular/metabolismo , Transformação Celular Neoplásica/metabolismo , Transformação Celular Neoplásica/patologia , Celulas Principais Gástricas/metabolismo , Celulas Principais Gástricas/patologia , Proteínas de Ligação a DNA/metabolismo , Proteínas Secretadas pelo Epidídimo/metabolismo , Proteínas Fetais/metabolismo , Gastrinas/metabolismo , Humanos , Peptídeos e Proteínas de Sinalização Intercelular , Fator Intrínseco/metabolismo , Metaplasia/metabolismo , Metaplasia/patologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Proteínas Associadas aos Microtúbulos , Componente 3 do Complexo de Manutenção de Minicromossomo , Proteínas Nucleares/metabolismo , Células Parietais Gástricas/metabolismo , Lesões Pré-Cancerosas/metabolismo , Lesões Pré-Cancerosas/patologia , Neoplasias Gástricas/metabolismo , Neoplasias Gástricas/patologia , Neoplasias Gástricas/fisiopatologia , Fator Trefoil-2 , beta-Defensinas
10.
J Chem Phys ; 127(15): 154704, 2007 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-17949188

RESUMO

Crystallization in n-alkane ultrathin films supported by solid substrates is investigated by molecular dynamics simulation. We consider a relatively short n-alkane, undecane C11H24, on a flat substrate of varied degree of attraction. By the use of the united atom model for n-alkane, we reveal several characteristics of the thin film crystallization. It is found that the crystalline films consist of thin crystalline lamellae where chains are either parallel or perpendicular to the substrate. The relative amount of both types of lamellae changes systematically with film thickness, substrate attraction, and crystallization temperature; thicker films on substrates of higher attraction comprise dominant parallel lamellae, while thinner films on substrates of weaker attraction prefer the perpendicular lamellae. A clue to the morphogenesis is suggested to be the marked preference of the chain ends to locate on the free surface and on the effectively repulsive substrate. It is also shown that the perpendicular crystals, both on the free surface and on the solid substrate, have melting points higher than that of the bulk.


Assuntos
Alcanos/química , Físico-Química/métodos , Simulação por Computador , Cristalização , Modelos Estatísticos , Estrutura Molecular , Transição de Fase , Especificidade por Substrato , Propriedades de Superfície , Temperatura , Fatores de Tempo
11.
Asian Pac J Cancer Prev ; 8(2): 267-71, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17696744

RESUMO

AIMS: We have previously demonstrated the importance of gastric and intestinal phenotypic expression for the histogenesis of stomach cancer. However, the phenotypes of stomach cancers arising after Helicobacter pylori (Hp) eradication have hitherto remained unclear. We therefore examined a series of lesions occurring after Hp eradication in the Mongolian gerbil (MG) model. METHODS: Totals of 6 and 20 advanced glandular stomach cancers were evaluated in Hp-eradicated and Hp-infected MGs treated with N-methyl-N-nitrosourea (MNU-MGs), using several gastrointestinal epithelial phenotypic markers. The lesions were divided phenotypically into gastric (G type), gastric-and-intestinal mixed (GI type), intestinal (I type), and null (N type) phenotypes. RESULTS: All 4 differentiated type lesions in Hp-eradicated MNU-MGs were classified as G type, while both of the undifferentiated lesions exhibit the GI type. In Hp-infected MNU-MGs, the lesions were classified as 10 G, 8 GI, and 2 I types, with undifferentiated type lesions having more intestinal phenotypic expression than their differentiated counterparts (P< 0.01). CONCLUSIONS: Our data suggest that the differentiated stomach cancers exhibit the G type in Hp-eradicated MNU-MGs, suggesting that a kind of non-neoplastic G type gland may be precancerous. Intestinalization may still occur, especially in undifferentiated stomach cancers, even if Hp eradication is successful.


Assuntos
Adenocarcinoma/genética , Infecções por Helicobacter/tratamento farmacológico , Helicobacter pylori/isolamento & purificação , Neoplasias Gástricas/genética , Neoplasias Gástricas/microbiologia , Adenocarcinoma/microbiologia , Adenocarcinoma/patologia , Animais , Carcinógenos , Modelos Animais de Doenças , Gerbillinae , Infecções por Helicobacter/complicações , Metilnitrosoureia/uso terapêutico , Fenótipo , Neoplasias Gástricas/patologia
13.
Cancer Sci ; 98(4): 478-83, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17284248

RESUMO

Helicobacter pylori (H. pylori) infection causes chronic gastritis and is also related to gastric carcinoma. The present study focused on severity of H. pylori-induced gastritis as a determinant of carcinogenesis. Seven-week-old male Mongolian gerbils were inoculated with H. pylori at experimental weeks 0, 12, or 18, then given N-methyl-N-nitorosourea (MNU) from weeks 20-40. At week 70, stomachs were then excised for histological examination 70, 58, or 52 weeks after H. pylori inoculation, respectively (Groups A, B, and C for long-, middle-, and short-term). The respective incidences of glandular stomach adenocarcinomas were 65.0% (13/20), 20.0% (2/10), and 23.0% (3/13) (P<0.05). Higher scores of infiltration of inflammatory cells, hyperplasia, intestinal metaplasia and mucosal bromodeoxyuridine (BrdU) labeling index in antrum and corpus mucosa, were seen in group A than B or C (P<0.05) and serum anti-H. pylori IgG titer and gastrin levels were also significantly higher, along with mRNA levels for mucosal interleukin-1beta (IL-1beta), tumor necrosis factor-alpha (TNF-alpha), cyclooxygenase-2 (COX-2), and inducible nitric oxide synthase (iNOS). The results demonstrated the term and severity of H. pylori infection to play important roles in gastric carcinogenesis, with essential involvement of chronic inflammation, especially increased rates of cell proliferation, in H. pylori-associated carcinogenesis.


Assuntos
Adenocarcinoma/microbiologia , Mucosa Gástrica/microbiologia , Gastrite/complicações , Infecções por Helicobacter/complicações , Helicobacter pylori , Neoplasias Gástricas/microbiologia , Adenocarcinoma/metabolismo , Animais , Mucosa Gástrica/metabolismo , Gastrite/microbiologia , Gerbillinae , Interleucina-1beta/metabolismo , Masculino , Fator de Necrose Tumoral alfa/metabolismo
14.
Gastric Cancer ; 9(3): 229-34, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16952043

RESUMO

A 71-year-old man with a Helicobacter pylori infection-negative and API2-MALT1 translocation-negative extranodal marginal-zone B-cell lymphoma of mucosa-associated lymphoid tissue (MALT) type of the stomach has been followed conservatively for over 5 years. The lesion has shown no major morphological changes or malignant progression into a diffuse large-cell type during the time course. The absence of genetic translocation of API2-MALT1 was confirmed with fluorescence in situ hybridization (FISH). The prognosis of H. pylori-negative and API2-MALT1 translocation-negative low-grade MALT lymphoma is unknown, and a standard treatment for such lymphoma has yet to be defined. The case of MALT lymphoma negative for both of the above factors that we report has shown no obvious rapid progression or malignant change over the long-term course. Although curative operation and/or chemoradiotherapy should still be discussed as the treatment of choice, the treatment of this type of lymphoma must be carefully determined on a case-by-case basis, according to its biological status and prognosis.


Assuntos
Helicobacter pylori/isolamento & purificação , Linfoma de Zona Marginal Tipo Células B/diagnóstico , Linfoma de Zona Marginal Tipo Células B/microbiologia , Linfoma não Hodgkin/diagnóstico , Proteínas de Fusão Oncogênica/genética , Neoplasias Gástricas/diagnóstico , Translocação Genética , Idoso , Gastroscopia/métodos , Humanos , Linfoma de Zona Marginal Tipo Células B/metabolismo , Linfoma não Hodgkin/genética , Linfoma não Hodgkin/microbiologia , Masculino , Neoplasias Gástricas/metabolismo , Neoplasias Gástricas/microbiologia
15.
Dig Dis Sci ; 50(5): 842-6, 2005 May.
Artigo em Inglês | MEDLINE | ID: mdl-15906755

RESUMO

In the present study, we aimed to establish an additional standardized protocol with a higher H. pylori eradication rate in the remnant stomach. Fifty-five H. pylori-positive patients were randomly allocated to one of three regimens: LAC--lansoprazole, amoxicillin, and clarithromycin b.i.d. for 7 days (n = 17); LAC+CET--LAC b.i.d. plus cetraxate q.i.d. for 7 days (n = 20); and LEFT--LAC for 7 days in a horizontal body position on the left side for 30 min (n = 18). Patient compliance and side effects were checked via interviews. H. pylori eradication was successful in 75, 72, and 41% in LAC+CET, LEFT, and LAC, respectively. The eradication rate was significantly higher in LAC+CET than in LAC (P = 0.024) but not in LEFT (P = 0.058). Adverse events that occurred in each group were almost all mild ones. Cetraxate plus LAC for 1 week is a safe and effective regime for the eradication of H. pylori in patients after partial gastrectomy.


Assuntos
Anti-Infecciosos/administração & dosagem , Antiulcerosos/administração & dosagem , Coto Gástrico , Infecções por Helicobacter/tratamento farmacológico , Helicobacter pylori , Omeprazol/análogos & derivados , Omeprazol/administração & dosagem , Ácido Tranexâmico/análogos & derivados , Ácido Tranexâmico/administração & dosagem , 2-Piridinilmetilsulfinilbenzimidazóis , Adulto , Idoso , Esquema de Medicação , Quimioterapia Combinada , Feminino , Gastrectomia/efeitos adversos , Infecções por Helicobacter/etiologia , Humanos , Lansoprazol , Masculino , Pessoa de Meia-Idade , Postura , Resultado do Tratamento
16.
Cancer Sci ; 96(3): 170-5, 2005 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15771620

RESUMO

Mongolian gerbils are an ideal animal model to explore the role of H. pylori on cancer development. However, there have been no established adenocarcinoma cell lines from this model animal. In the present study, we have established cancer cell lines from a primary gastric cancer tissue of a Mongolian gerbil. The derived cells could be stably attached with H. pylori, revealed under a scanning electron microscope, and easily transplanted to the nude mice. Rapid phosphorylation of IkappaB, Erk1/2, and AKT of these cells was observed by Interleukin-1 beta stimulation, and luciferase reporter gene assay on transcriptional activation of Nuclear Factor kappa B after challenging with either H. pylori NCTC11637 or its isogenic cagE-knockout mutant, H. pylori revealed the cagE-dependent NF-kappaB transcriptional activation. The newly established cancer cell lines from the in vivo gastric carcinogenesis model animal, the Mongolian gerbil, can be used to develop effective therapeutic strategies against gastric cancer, especially in exploring the effect of H. pylori, and thus might greatly contribute to gastric cancer prevention and treatment in humans.


Assuntos
Modelos Animais de Doenças , Infecções por Helicobacter/complicações , Helicobacter pylori/patogenicidade , NF-kappa B/biossíntese , Neoplasias Gástricas/microbiologia , Neoplasias Gástricas/patologia , Animais , Regulação da Expressão Gênica , Gerbillinae , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , NF-kappa B/genética , Invasividade Neoplásica , Neoplasias Gástricas/veterinária , Células Tumorais Cultivadas
17.
Biotechnol Lett ; 27(4): 259-63, 2005 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-15742147

RESUMO

To confer the ability to ferment cello-oligosaccharides on the ethanol-producing bacterium, Zymomonas mobilis, the beta-glucosidase gene from Ruminococcus albus, tagged at its N-terminal with the 53-amino acid Tat signal peptide from the periplasmic enzyme glucose-fructose oxidoreductase from Z. mobilis, was introduced into the strain. The tag enabled 61% of the beta-glucosidase activity to be transported through the cytoplasmic membrane of the recombinant strain which then produced 0.49 g ethanol/g cellobiose.


Assuntos
Celobiose/metabolismo , Etanol/metabolismo , Melhoramento Genético/métodos , Engenharia de Proteínas/métodos , Ruminococcus/metabolismo , Zymomonas/metabolismo , beta-Glucosidase/genética , beta-Glucosidase/metabolismo , Celulose/metabolismo , Proteínas Recombinantes de Fusão/metabolismo , Ruminococcus/genética , Zymomonas/genética
18.
Cancer Sci ; 95(11): 872-7, 2004 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-15546504

RESUMO

Mongolian gerbils infected with Helicobacter pylori (H. pylori ) develop heterotopic proliferative glands (HPGs) in the glandular stomach submucosa. To investigate the effects of H. pylori eradication on cell turnover in HPGs, three antibiotics, lansoprazole, amoxicillin and clarithromycin, were administered at 50 or 75 weeks after inoculation of H. pylori, and the stomachs were excised for histological examination at 1, 2, 4, 8 or 25 weeks thereafter. The HPGs were classified into gastric type (G-type) and others (GI + I-type), which included both pure intestinal (I-type) and gastric-and-intestinal mixed type (GI-type). Apoptosis and cell proliferation were evaluated by means of TUNEL assay and BrdU labeling, respectively. At 8 weeks post-eradication, apoptotic indices were significantly increased in the eradication group (G-type: 2.5%; GI + I-type: 7.2%) compared to the non-eradication group (G-type: 0.6%; GI + I-type: 2.1%: P < 0.01), while BrdU labeling indices were significantly decreased (G-type: 1.9%; GI + I-type: 6.8% as compared with 4.3% and 13.2%, respectively, P < 0.01 for both). At 25 weeks, the apoptotic indices were similarly higher [G-type: 0.4 (eradication group) vs. 0.2% (non-eradication group); GI + I-type: 5.8 vs. 1.1%, both P < 0.01], and the BrdU labeling indices (G-type: 0.8 vs. 2.2%, P < 0.01; GI + I-type: 5.1 vs. 11%, P < 0.05) continued to be lower in HPGs. Furthermore, there were highly significant reductions in the areas of HPGs at 8 and 25 weeks post-eradication. These findings demonstrated that eradication results in apoptosis and reduction of proliferation of HPGs in H. pylori-infected gerbils, these lesions thus being apparently reversible through regulation of cell kinetics.


Assuntos
Amoxicilina/uso terapêutico , Antibacterianos/uso terapêutico , Coristoma/tratamento farmacológico , Mucosa Gástrica , Infecções por Helicobacter/patologia , Helicobacter pylori , Omeprazol/análogos & derivados , 2-Piridinilmetilsulfinilbenzimidazóis , Animais , Apoptose , Proliferação de Células , Claritromicina/uso terapêutico , Gerbillinae , Infecções por Helicobacter/tratamento farmacológico , Intestinos , Lansoprazol , Omeprazol/uso terapêutico , Estômago
19.
Cancer Sci ; 95(6): 487-90, 2004 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15182428

RESUMO

The goal of this study was to elucidate whether beta-catenin gene mutations might contribute to glandular stomach carcinogenesis in Helicobacter pylori (H.pylori)-infected Mongolian gerbils. Firstly, exon 3 of gerbil beta-catenin cDNA, a mutation hot spot, was cloned and sequenced and found to have 89.3% homology with the human form and 95.5% with the rat and mouse forms. Peptide sequence in this region was shown to be 100% conserved in these mammals. Then, 45 stomach adenocarcinomas induced with N-methyl-N-nitrosourea (MNU) plus H. pylori infection and 7 induced with MNU alone were examined for beta-catenin expression by immunohistochemistry and for DNA mutations using a combination of microdissection and PCR-single strand conformation polymorphism analysis. One gastric cancer in the MNU + H. pylori group (2.2%) displayed nuclear (N) beta-catenin localization, 3 (6.7%) showed cytoplasmic (C) distribution in local regions, and 41 (91.1%) demonstrated cell membrane (M) localization. Tumors induced by MNU alone showed only membranous beta-catenin localization (7/7). Analysis of exon 3 of the beta-catenin gene dem-onstrated all tumors with membrane or cytoplasmic staining as well as surrounding normal mucosa (S) to feature wild-type beta-catenin. In contrast, the lesion with nuclear staining had a missense mutation at codon 34 [GAC (Gly) --> GAA (Glu)] in exon 3 (1/1 = 100%, N vs. M, P < 0.05; and N vs. S, P < 0.05). In conclusion, these results suggest that beta-catenin may not be a frequent target for mutation in stomach carcinogenesis in MNU + H. pylori-treated gerbils.


Assuntos
Adenocarcinoma/genética , Proteínas do Citoesqueleto/genética , Infecções por Helicobacter/complicações , Helicobacter pylori , Mutação , Neoplasias Gástricas/genética , Transativadores/genética , Adenocarcinoma/etiologia , Sequência de Aminoácidos , Animais , Sequência de Bases , Proteínas do Citoesqueleto/química , Éxons , Gerbillinae , Masculino , Metilnitrosoureia , Dados de Sequência Molecular , Neoplasias Gástricas/etiologia , Transativadores/química , beta Catenina
20.
J Cancer Res Clin Oncol ; 130(1): 29-36, 2004 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-14615935

RESUMO

PURPOSE: It is well known that gastric cancers (GCs) at early stages, independent of the histological type, mainly consist of gastric phenotype malignant cells, while those at advanced stage tend to have a more intestinal phenotype with progression. However, the connection between this shift and expression of homeobox genes, which are important factors to maintain tissue character, has remained unclear. We therefore evaluated the expression of Cdx1/2 in relation to the phenotype of GCs. METHODS: We analyzed the expression of Cdx1/2 mRNAs by Northern blotting and Cdx2 protein by immunohistochemistry in seventy advanced GCs, and evaluated phenotypically using mucin- and immunohistochemistry. RESULTS: Seventy GCs were divided phenotypically into 16 gastric (G type), 18 gastric and intestinal mixed (GI type), 18 intestinal (I type), and 18 null (N type) phenotypes, independent of the histological classification. Cdx1 and Cdx2 mRNAs statistically demonstrated an increase with shift from G to I ( P=0.042 and P=0.0082, respectively). Cdx2 nuclear staining was observed immunohistochemically in the intestinal phenotypic cancer cells, but could not be detected in those with only the gastric phenotype. CONCLUSIONS: These results show that Cdx1 and Cdx2 might be indispensable for intestinal phenotypic expression even in gastric cancer cells.


Assuntos
Biomarcadores Tumorais/análise , Proteínas de Homeodomínio/análise , Intestinos , Neoplasias Gástricas/química , Fatores de Transcrição/análise , Biomarcadores Tumorais/genética , Northern Blotting , Fator de Transcrição CDX2 , Regulação Neoplásica da Expressão Gênica , Proteínas de Homeodomínio/genética , Humanos , Imuno-Histoquímica , Fenótipo , RNA Mensageiro/análise , Transativadores , Células Tumorais Cultivadas
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...