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1.
Gut ; 66(1): 6-30, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27707777

RESUMO

Important progress has been made in the management of Helicobacter pylori infection and in this fifth edition of the Maastricht Consensus Report, key aspects related to the clinical role of H. pylori were re-evaluated in 2015. In the Maastricht V/Florence Consensus Conference, 43 experts from 24 countries examined new data related to H. pylori in five subdivided workshops: (1) Indications/Associations, (2) Diagnosis, (3) Treatment, (4) Prevention/Public Health, (5) H. pylori and the Gastric Microbiota. The results of the individual workshops were presented to a final consensus voting that included all participants. Recommendations are provided on the basis of the best available evidence and relevance to the management of H. pylori infection in the various clinical scenarios.


Assuntos
Antibacterianos/uso terapêutico , Infecções por Helicobacter/diagnóstico , Infecções por Helicobacter/tratamento farmacológico , Helicobacter pylori , Inibidores da Bomba de Prótons/uso terapêutico , Neoplasias Gástricas/diagnóstico , Amoxicilina/uso terapêutico , Bismuto/uso terapêutico , Claritromicina/uso terapêutico , Farmacorresistência Bacteriana , Quimioterapia Combinada , Dispepsia/microbiologia , Detecção Precoce de Câncer , Medicina Baseada em Evidências , Fluoroquinolonas/uso terapêutico , Gastrite/microbiologia , Microbioma Gastrointestinal , Gastroscopia , Infecções por Helicobacter/complicações , Infecções por Helicobacter/prevenção & controle , Humanos , Testes de Sensibilidade Microbiana , Nitroimidazóis/uso terapêutico , Guias de Prática Clínica como Assunto , Fatores de Risco , Estômago/microbiologia , Neoplasias Gástricas/microbiologia
2.
Gut ; 64(10): 1650-68, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26342014

RESUMO

The stomach is traditionally regarded as a hollow muscular sac that initiates the second phase of digestion. Yet this simple view ignores the fact that it is the most sophisticated endocrine organ with unique physiology, biochemistry, immunology and microbiology. All ingested materials, including our nutrition, have to negotiate this organ first, and as such, the stomach is arguably the most important segment within the GI tract. The unique biological function of gastric acid secretion not only initiates the digestive process but also acts as a first line of defence against food-borne microbes. Normal gastric physiology and morphology may be disrupted by Helicobacter pylori infection, the most common chronic bacterial infection in the world and the aetiological agent for most peptic ulcers and gastric cancer. In this state-of-the-art review, the most relevant new aspects of the stomach in health and disease are addressed. Topics include gastric physiology and the role of gastric dysmotility in dyspepsia and gastroparesis; the stomach in appetite control and obesity; there is an update on the immunology of the stomach and the emerging field of the gastric microbiome. H. pylori-induced gastritis and its associated diseases including peptic ulcers and gastric cancer are addressed together with advances in diagnosis. The conclusions provide a future approach to gastric diseases underpinned by the concept that a healthy stomach is the gateway to a healthy and balanced host. This philosophy should reinforce any public health efforts designed to eradicate major gastric diseases, including stomach cancer.


Assuntos
Gastropatias/diagnóstico , Gastropatias/metabolismo , Estômago/anatomia & histologia , Estômago/fisiologia , Mucosa Gástrica/metabolismo , Humanos
3.
Eur J Pharm Sci ; 168: 106043, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34662708

RESUMO

An important goal of the European Cooperation in Science and Technology (COST) Action UNGAP (UNderstanding Gastrointestinal Absorption-related Processes, www.ungap.eu) is to improve standardization of methods relating to the study of oral drug absorption. Solubility is a general term that refers to the maximum achievable concentration of a compound dissolved in a liquid medium. For orally administered drugs, relevant information on drug properties is crucial during drug (product) development and at the regulatory level. Collection of reliable and reproducible solubility data requires careful application and understanding of the limitations of the selected experimental method. In addition, the purity of a compound and its solid state form, as well as experimental parameters such as temperature of experimentation, media related factors, and sample handling procedures can affect data quality. In this paper, an international consensus developed by the COST UNGAP network on recommendations for collecting high quality solubility data for the development of orally administered drugs is proposed.


Assuntos
Confiabilidade dos Dados , Preparações Farmacêuticas , Administração Oral , Absorção Intestinal , Solubilidade
4.
Cancer Sci ; 99(9): 1715-9, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18624996

RESUMO

Recently, a high rate of endometrial cancer has been reported in women with hereditary non-polyposis colorectal cancer (HNPCC), suggesting a relationship between familial endometrial cancers and HNPCC. Familial endometrial cancers constitute only about 0.5% of all endometrial carcinomas and it is essential to examine family histories in detail. A mutational analysis of three DNA mismatch repair (MMR) genes (hMLH1, hMSH2 and hMSH6) in patients with endometrial cancer who meet our criteria for familial predisposition to HNPCC-associated endometrial cancers was performed. Mutations were detected in 18 of the 120 patients (15.0%). Most HNPCC-related endometrial cancers do not meet the New Amsterdam Criteria for HNPCC. These clinical criteria may identify only some HNPCC-associated endometrial cancers. Establishing the correct family history for endometrial cancer patients is important for diagnosing familial endometrial carcinomas. An analysis of MMR genes may be useful for patients with endometrial cancer showing familial aggregation. In addition, gynecologists must be accurately informed, and it is important to perform large-scale, multicenter studies both nationwide and internationally.


Assuntos
Neoplasias Colorretais Hereditárias sem Polipose/genética , Reparo de Erro de Pareamento de DNA , Neoplasias do Endométrio/genética , Predisposição Genética para Doença , Adulto , Idoso , Neoplasias Colorretais Hereditárias sem Polipose/complicações , Análise Mutacional de DNA , Neoplasias do Endométrio/complicações , Feminino , Humanos , Pessoa de Meia-Idade
5.
J Clin Invest ; 79(3): 935-42, 1987 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-2880870

RESUMO

Bombesin, a polypeptide derived from frog skin, has been shown to stimulate gastrin release from the gastric antrum in vivo and in vitro. To elucidate the mechanisms of this effect, we developed a method to culture isolated and enriched G cells from canine stomach. After digestion of antral mucosa with collagenase and EDTA, dispersed cells were fractionated by counterflow elutriation then cultured on a collagen support. Bombesin and three molecular forms of canine gastrin-releasing peptides all stimulated gastrin release from G cells in a dose-dependent manner. The effect of bombesin was suppressed by somatostatin and potentiated by dibutyryl cyclic AMP (10(-3) M) but not by carbachol (10(-6) M). Extracellular calcium depletion attenuated the stimulation of gastrin release by bombesin but not by forskolin. These findings suggest that the bombesin family peptides directly activate G cells through calcium-dependent mechanisms to cause gastrin release.


Assuntos
Bombesina/farmacologia , Mucosa Gástrica/metabolismo , Gastrinas/metabolismo , Peptídeos/farmacologia , Animais , Bucladesina/farmacologia , Cálcio/fisiologia , Células Cultivadas , Colforsina/farmacologia , Cães , Mucosa Gástrica/efeitos dos fármacos , Peptídeo Liberador de Gastrina , Antro Pilórico/metabolismo , Somatostatina/farmacologia
8.
Cancer Res ; 58(3): 512-8, 1998 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-9458099

RESUMO

The effect of doses of the secretor (Se) and Lewis (Le) genes on the serum levels of CA19-9 and DU-PAN-2 was investigated in 400 normal individuals. It was clearly demonstrated that the Se gene dosage negatively affected both the CA19-9 and DU-PAN-2 values, whereas the Le gene dosage positively affected the CA19-9 value and negatively affected the DU-PAN-2 value. The 400 normal individuals were separated into nine groups by their Le and Se genotypes, as follows: group 1, Le/Le and se/se; group 2, Le/le and se/se; group 3, Le/Le and Se/se; group 4, Le/le and Se/se; group 5, Le/Le and Se/Se; group 6, Le/le and Se/Se; group 7, le/le and se/se; group 8, le/le and Se/se; and group 9, le/le and Se/Se. The group 1 individuals, having homozygous inactive Se alleles (se/se) and homozygous active Le alleles (Le/Le), exhibited the highest mean CA19-9 value. The CA19-9 value clearly ranged from a high in group 1 to a low in group 9. All of the Le-negative individuals who had the le/le genotype (groups 7, 8, and 9) had completely negative CA19-9 values, i.e., under 1.0 unit/ml, irrespective of the Se genotype. Group 7 individuals (le/le and se/se) showed a higher mean DU-PAN-2 value than did individuals in other groups. The Le-negative individuals in groups 8 and 9 also showed a higher mean DU-PAN-2 value than did the Le-positive individuals in groups 1-6. We recommend that the revised Le and Se genotype-dependent positive/negative cutoff values for CA19-9 and DU-PAN-2, determined in this study, be applied for more accurate cancer diagnoses. The Le and Se genotypes of 168 patients with colorectal cancer were also examined, and the CA19-9 and DU-PAN-2 values were measured before surgical resection. All 15 Le-negative patients (le/le) with colorectal cancer again showed undetectable CA19-9 values, i.e., under 1.0 unit/ml, but many of them exhibited highly positive DU-PAN-2 values. In contrast, many of the Le-positive patients (Le/Le or Le/le) had positive CA19-9 values, whereas very few of them exhibited positive DU-PAN-2 values. CA19-9 measurement is more useful than is DU-PAN-2 measurement for Le-positive patients, but it is not useful for Le-negative ones. DU-PAN-2 measurement should be performed in Le-negative patients for cancer diagnosis.


Assuntos
Antígenos de Neoplasias/sangue , Biomarcadores Tumorais/sangue , Antígeno CA-19-9/sangue , Neoplasias Colorretais/sangue , Fucosiltransferases/genética , Proteínas de Neoplasias/sangue , Processamento de Proteína Pós-Traducional/genética , Alelos , Antígenos de Neoplasias/metabolismo , Biomarcadores Tumorais/metabolismo , Antígeno CA-19-9/metabolismo , Sequência de Carboidratos , Neoplasias Colorretais/genética , Epitopos/genética , Epitopos/metabolismo , Dosagem de Genes , Genótipo , Glicosilação , Humanos , Dados de Sequência Molecular , Proteínas de Neoplasias/metabolismo , Fenótipo , Galactosídeo 2-alfa-L-Fucosiltransferase
9.
Oncogene ; 19(12): 1564-71, 2000 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-10734316

RESUMO

High-frequent microsatellite instability (MSI-H) was detected in two of the 80 gliomas examined, whlie the other 78 gliomas showed microsatellite stable (MSS) phenotype. Both of the two MSI-H tumors were glioblastomas which developed in teenage patients. One of the patient was diagnosed as having Turcot's syndrome and had a germline mutation in the hMLH1 gene. Loss of expression due to promoter methylation was selectively observed in the wild type allele of the hMLH1 gene in the tumor of this patient. The other patient had neither a family history nor a past personal history of malignancy. Although no mutation in the mismatch repair genes was detected in the tumor of this patient, the level of expression of the hMLH1 gene was markedly decreased and the promoter sequence of the gene was highly methylated. In the tumor of this patient, the PTEN1 gene, one of the genes carrying microsatellite sequences in their coding regions, was altered by a slippage mutation within five adenine repeat sequences. These findings indicate that the genetic or epigenentic inactivation of the hMLH1 gene is involved in a subset of early-onset gliomas and the PTEN1 gene could be a downstream target for mutation as observed in glioblastoma without MSI.


Assuntos
Glioma/genética , Mutação , Proteínas de Neoplasias/genética , Neoplasias do Sistema Nervoso/genética , Proteínas Adaptadoras de Transdução de Sinal , Idade de Início , Proteínas de Transporte , Metilação de DNA , Inativação Gênica , Mutação em Linhagem Germinativa , Humanos , Repetições de Microssatélites , Proteína 1 Homóloga a MutL , Proteínas Nucleares , Regiões Promotoras Genéticas
10.
Biochim Biophys Acta ; 961(2): 213-22, 1988 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-3390457

RESUMO

Neutral and acidic glycosphingolipids from various regions of the rabbit gastrointestinal tract showed different but characteristic patterns. In particular, sulfatides were found to be present in high concentrations in the mucosal regions frequently exposed to gastric acid, such as the gastric mucosa and proximal intestinal mucosa (duodenum and jejunum). The majority of sulfatides in these tissues have been identified as GalCer-I3-sulfate, with alpha-hydroxy long-chain fatty acids, by chemical procedures including analysis by negative ion fast atom bombardment mass spectrometry. The concentrations of GalCer-I3-sulfate in the fundic mucosa, antral mucosa, duodenum, and jejunum were 394.0, 356.9, 829.3, and 378.1 nmol/g of dry weight, respectively. These concentrations exceed those in the kidney, which has been reported to contain the highest concentration of sulfatides, with the exception of the nervous system, also, especially in the fundic mucosa, gangliosides were drastically reduced, in contrast to sulfatides: the molar ratio of sulfatides to GM3, the major ganglioside, was about 11:1. In addition, in the acid hydrolysis experiment, using the same concentration of HCl as that present in the gastric juices, sulfatide proved to be much more resistant to acid than GM3. Therefore, the preferential distribution of sulfatides in the mucosal regions exposed to acid may be related to mucosal functions, such as acid secretion and protection from acidic environments.


Assuntos
Mucosa Gástrica/análise , Glicoesfingolipídeos/análise , Mucosa Intestinal/análise , Sulfoglicoesfingolipídeos/análise , Animais , Cromatografia em Camada Fina , Gangliosídeo G(M3)/metabolismo , Ácido Gástrico , Coelhos , Sulfoglicoesfingolipídeos/metabolismo
11.
Aliment Pharmacol Ther ; 21 Suppl 2: 92-8, 2005 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15943854

RESUMO

BACKGROUND: Helicobacter pylori infection prevents the occurrence of the tolerance phenomenon of Histamine-2 (H2) receptor antagonists. Gastro-esophageal reflux disease develops in some cases with the restoration of acid secretion after H. pylori eradication therapy. AIM: To clarify the mechanisms of H2 receptor restoration after the eradication of H. pylori on parietal cells. METHODS: We enrolled 80 consecutive asymptomatic male patients with H. pylori infection, having chronic gastritis with or without the presence of peptic ulcers. Biopsy specimens from the greater curvatures at the mid-corpus of the stomach were obtained endoscopically from all subjects before and 12 weeks after the eradication of H. pylori. Degrees of gastric atrophy were evaluated by serum pepsinogen levels. The amounts of mRNA expression of H2 receptor were evaluated in each subject's gastric mucosa by real time reverse transcriptase-polymerase chain reaction (RT-PCR). RESULTS: H2 receptor mRNA expression levels significantly correlated with serum pepsinogens I and II ratios. The expression level of H2 receptor mRNA was lower in subjects with hypergastrinemia. The median expression level of H2 receptor after H. pylori eradication was threefold greater than prior to treatment. In addition, its restoration became more pronounced in subjects with severe gastric atrophy. However, a comparatively low restoration of H2 receptor mRNA was found in subjects with hypergastrinemia. CONCLUSIONS: H2 receptor mRNA levels decrease with the progression of gastric atrophy induced by H. pylori infection, and are restored after H. pylori eradication. Such expression levels of H2 receptor may explain a part of the tolerance phenomenon to H2 receptor antagonists.


Assuntos
Antibacterianos , Quimioterapia Combinada/uso terapêutico , Infecções por Helicobacter/tratamento farmacológico , Helicobacter pylori , Receptores Histamínicos H2/metabolismo , Ácido Gástrico/metabolismo , Mucosa Gástrica/metabolismo , Mucosa Gástrica/microbiologia , Infecções por Helicobacter/metabolismo , Humanos , Masculino , Pessoa de Meia-Idade , RNA Mensageiro/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa
12.
Aliment Pharmacol Ther ; 21 Suppl 2: 105-10, 2005 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15943856

RESUMO

BACKGROUND: To date, there has not been an in-depth investigation to identify differences in the effects of bleeding prevention among different routes of administration of H2 receptor antagonists to treat gastric ulcers following endoscopic mucosal resection (EMR). AIM: To prospectively compare the frequency of bleeding following EMR between patients treated with intravenous (IV) famotidine and those with oral famotidine. METHODS: Fifty-three patients with neoplastic gastric lesions (33 carcinoma and 20 adenoma) treated by EMR were included. Subjects underwent EMR with circumferential mucosal incision assisted by submucosal injection of sodium hyaluronate (EMRSH), followed by IV or oral (PO) administration of famotidine at a dosage of 40 mg/day for 2 days. Patients with odd ID numbers were assigned to IV therapy (30 cases) while even numbers were given PO therapy (23 cases). Frequencies and endoscopic findings of bleeding during the first 2 days after EMR were examined. RESULTS: Frequency of bleeding within 2 days after EMR was 3 and 4% in IV and PO patients, respectively, showing no significant difference. No significant difference was seen in the endoscopic findings of bleeding and therapy, either, with respective IV and PO findings at 23 and 26%. CONCLUSIONS: No significant difference was observed in frequency of bleeding within 2 days after gastric EMR between IV and oral administrations of famotidine.


Assuntos
Adenocarcinoma/tratamento farmacológico , Famotidina/administração & dosagem , Hemorragia Gastrointestinal/prevenção & controle , Antagonistas dos Receptores H2 da Histamina/administração & dosagem , Hemorragia Pós-Operatória/prevenção & controle , Neoplasias Gástricas/tratamento farmacológico , Adenocarcinoma/cirurgia , Adjuvantes Imunológicos/administração & dosagem , Administração Oral , Idoso , Endoscopia Gastrointestinal/efeitos adversos , Feminino , Hemorragia Gastrointestinal/etiologia , Hemostase Endoscópica/efeitos adversos , Humanos , Ácido Hialurônico/administração & dosagem , Infusões Intravenosas , Mucosa Intestinal/cirurgia , Masculino , Pessoa de Meia-Idade , Hemorragia Pós-Operatória/etiologia , Estudos Prospectivos , Recidiva , Neoplasias Gástricas/cirurgia
13.
Clin Cancer Res ; 3(11): 2143-9, 1997 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-9815608

RESUMO

K-ras point mutations have been observed in approximately 90% of pancreatic carcinomas. We genetically analyzed cases of pancreatic regional lymph nodal and plexus micrometastases in invasive ductal carcinoma of the pancreas who were node negative or had metastases limited histopathologically to pancreaticoduodenal lymph nodes. These cases underwent curative resection in our institute. The utility of genetic analysis was compared with that of histopathological study, in terms of postoperative clinical outcome, as a predictive factor for recurrent pancreatic carcinoma. Samples for DNA extraction were obtained from formalin-fixed, paraffin-embedded specimens. A 0.5-microg quantity of DNA was subjected to enriched PCR and nonradioisotopic single-strand conformation polymorphism analysis. K-ras codon 12 mutations were detected in 83% (10 of 12) of invasive ductal carcinomas. In four cases, the genetic analysis of regional lymph nodal metastases and pancreatic plexus invasion of the pancreatic carcinoma yielded results concordant with those of histopathological analysis. In six cases, however, the metastases detected by genetic analysis were more advanced than was indicated by the histopathological examination. The survival rate of cases with metastases beyond the pancreaticoduodenal lymph nodes was significantly lower than that of cases with metastases limited to the pancreaticoduodenal lymph nodes or with no nodal involvement based on genetic analysis (P < 0.05). Intraoperative analysis of point mutations at K-ras codon 12 in the regional lymph nodes and the pancreatic plexus by enriched PCR/nonradioisotopic single-strand conformation polymorphism analysis is a highly accurate predictive factor for recurrent pancreatic carcinoma.


Assuntos
Carcinoma Intraductal não Infiltrante/genética , Carcinoma Intraductal não Infiltrante/patologia , Genes ras , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/patologia , Mutação Puntual , Polimorfismo Conformacional de Fita Simples , Adulto , Idoso , Carcinoma Intraductal não Infiltrante/mortalidade , Carcinoma Intraductal não Infiltrante/cirurgia , Códon , DNA de Neoplasias/genética , DNA de Neoplasias/isolamento & purificação , Intervalo Livre de Doença , Feminino , Humanos , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Invasividade Neoplásica , Metástase Neoplásica , Neoplasias Pancreáticas/mortalidade , Neoplasias Pancreáticas/cirurgia , Reação em Cadeia da Polimerase/métodos , Valor Preditivo dos Testes , Recidiva , Análise de Sobrevida , Resultado do Tratamento
14.
FEBS Lett ; 337(1): 27-32, 1994 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-8276107

RESUMO

We made a mutated progastrin cDNA construct that contains a cleavage site (-Arg(-4)-Arg(-3)-Lys(-2)-Arg-1) specific for the Kex2-like endoprotease furin, located ahead of the bioactive gastrin. For expressing the mutated progastrin cDNA, we used two non-endocrine cell lines, CHO and COS-7. CHO cells exhibit amidating enzyme activity and levels of amidation enzyme mRNA as high as those in the pituitary-derived endocrine cell line GH3, whereas COS-7 cells have far less amidating activity and lower amounts of mRNA. Mutant progastrin-expressing CHO cells produced mostly amidated gastrin. Gel filtration showed the size of this gastrin corresponded to that of the synthetic human gastrin-17. In contrast, COS-7 cells produced glycine-extended gastrin and only a small amount of amidated gastrin. The difference in the amount of amidated gastrin products produced by the two non-endocrine cell lines is due to differing amounts of the amidation enzyme contained in each cell line.


Assuntos
Gastrinas/biossíntese , Complexos Multienzimáticos , Sequência de Aminoácidos , Animais , Sítios de Ligação , Células CHO/metabolismo , Linhagem Celular , Chlorocebus aethiops , Cromatografia em Gel , Cricetinae , DNA Complementar/genética , Furina , Gastrinas/genética , Expressão Gênica , Humanos , Rim , Oxigenases de Função Mista/metabolismo , Dados de Sequência Molecular , Mutagênese , Precursores de Proteínas/genética , RNA Mensageiro/metabolismo , Ratos , Subtilisinas/metabolismo , Transfecção
15.
FEBS Lett ; 282(2): 385-7, 1991 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-2037054

RESUMO

Helicobacter pylori has been identified as a causative agent in active chronic gastritis. The receptor for this bacteria, however, is not known. It is likely that the receptor molecules may be glycosphingolipids as shown in the cases of other bacteria. We explored this possibility by a thin-layer chromatography (TLC)-immunostaining method. Among glycosphingolipids extracted from human gastric mucosa, intact Helicobacter pylori specifically bound to I3SO3-GalCer and II3NeuAc-LacCer, whereas no specific binding to neutral glycosphingolipids, which share the same ceramide moiety with I3SO3-GalCer or II3NeuAc-LacCer, was demonstrated. Sonicated bacteria could still bind to II3NeuAc-LacCer with comparable affinity. In contrast, the binding of bacteria to I3SO3-GalCer was greatly diminished upon sonication. These results suggest that each of the oligosaccharide moieties of II3NeuAc-LacCer and I3SO3-GalCer may be specifically recognized by different ligand molecules of Helicobacter pylori.


Assuntos
Mucosa Gástrica/química , Gastrite/microbiologia , Glicolipídeos/metabolismo , Helicobacter pylori/metabolismo , Aderência Bacteriana , Mucosa Gástrica/metabolismo , Mucosa Gástrica/microbiologia , Humanos , Técnicas In Vitro
16.
FEBS Lett ; 409(2): 283-6, 1997 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-9202162

RESUMO

A histamine H2 receptor, which had been mutated at its glycosylation site and tagged at its N-terminus with an HA tag (HA-H2 receptor), was expressed in Sf9 cells and COS7 cells. Immunoprecipitation and immunoblotting of HA-H2 receptors with alphaHA antibody revealed four bands of 31.5 +/- 2.5 kDa, 59.0 +/- 6.0 kDa, 80.5 +/- 4.5 kDa and 120 kDa. These bands were also detected by immunoblot using anti-H2 receptor serum (C-terminus). In addition, H2 receptors without the HA-tag coimmunoprecipitated with HA-tagged H2 receptors devoid of the 51 C-terminal amino acids, via immunoprecipitation with alphaHA antibody, when the two receptors were coexpressed. These results suggest that H2 receptors are present as receptor oligomers and that the C-terminal portion is not involved in the formation of these oligomers.


Assuntos
Receptores Histamínicos H2/biossíntese , Receptores Histamínicos H2/química , Animais , Células COS , Clonagem Molecular , Hemaglutininas/genética , Immunoblotting , Peso Molecular , Testes de Precipitina , Receptores Histamínicos H2/genética , Spodoptera/citologia , Spodoptera/genética , Spodoptera/metabolismo
17.
J Histochem Cytochem ; 37(3): 287-92, 1989 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-2918220

RESUMO

To identify and characterize the subcellular topography of glycine-extended pro-gastrin-processing intermediates (G-Gly) in human antral mucosa, we performed an electron microscopic immunocytochemical study using region-specific antisera generated against the synthetic peptide, Tyr-Gly-Trp-Met-Asp-Phe-Gly (GL7), and C-terminal-specific anti-gastrin antisera. As has been previously reported, G-cells contained both electron-dense and electron-lucent granules, with a range of intermediate forms. Gastrin immunoreactivity was demonstrated in almost all granules of each type, whereas anti-GL7 antisera immunostained chiefly electron-dense granules. The relative ratio of GL7/gastrin granules varied among different cells but was approximately 1:10 on average. Other cytoplasmic organelles were devoid of specific labeling for GL7 or gastrin. As we have assumed that G-Gly serves as the immediate precursor for each molecular form of gastrin, electron-dense granules with high labeling for GL7 are regarded as the principal site for conversion of G-Gly to gastrin. This speculation supports many previous reports that electron-dense granules are immature and that the granules become less electron-dense with maturation.


Assuntos
Mucosa Gástrica/análise , Gastrinas/análise , Imuno-Histoquímica , Adulto , Sequência de Aminoácidos , Grânulos Citoplasmáticos/análise , Feminino , Mucosa Gástrica/ultraestrutura , Humanos , Masculino , Microscopia Eletrônica , Pessoa de Meia-Idade , Dados de Sequência Molecular , Organelas/análise , Antro Pilórico
18.
J Biomol Screen ; 6(3): 189-96, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11689115

RESUMO

The purpose of the present study was to improve the composition of the lipid solution used in parallel artificial membrane permeation assay for the precise prediction of oral absorption. We modified the composition of lipid solution, which was used to make a lipid membrane on the filter support. First, we changed the chain length of organic solvent (PC/alkyldienes [C7-C10]). A negative charge was then added to the membrane to mimic the intestinal membrane (PC/stearic acid/1,7-octadiene and PC/PE/PS/PI/cholesterol/1,7-octadiene). Finally, we examined the predictability of the PC/PE/PS/PI/CHO/1,7-octadiene membrane using structurally diverse compounds. Permeability coefficients of tested compounds were increased as the chain length of alkyldiene became shorter. The addition of a negative charge to the membrane increased the permeability of the basic compounds. However, the negatively charged membrane with stearic acid showed different permeability profiles from PC/PE/PS/PI/CHO. The predictability of the PC/PE/PS/PI/CHO/1,7-octadiene membrane was adequate (r = 0.858, n = 31) for use during the early stages of the drug discovery/development process.


Assuntos
Permeabilidade da Membrana Celular , Lipídeos de Membrana/metabolismo , Membranas Artificiais , Preparações Farmacêuticas/química , Preparações Farmacêuticas/metabolismo , Absorção , Administração Oral , Química Farmacêutica , Modelos Biológicos , Compostos Orgânicos/química , Solubilidade , Soluções , Solventes/química , Termodinâmica
19.
Cancer Lett ; 142(1): 105-10, 1999 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-10424788

RESUMO

Germline MEN1 gene mutations are responsible for multiple endocrine neoplasia type 1 (MEN1), a dominantly inherited cancer syndrome. We identified a MEN1 germline mutation 894-9 G --> A in three MEN1 patients from two unrelated families. This mutation was not present in any of the 100 blood samples from normal volunteers. The wild type MEN1 sequence was lost in the patient's pancreatic tumor. Abnormal mRNA was identified in the tumor, which retained an intronic sequence indicating aberrant mRNA splicing at a newly created splicing acceptor site. These findings indicate that this nucleotide substitution is, though previously reported to be a polymorphism, a causative splicing mutation.


Assuntos
Neoplasia Endócrina Múltipla Tipo 1/genética , Mutação , Proteínas de Neoplasias/genética , Proteínas Proto-Oncogênicas , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Polimorfismo Genético , Splicing de RNA
20.
Aliment Pharmacol Ther ; 14(8): 1083-7, 2000 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10930904

RESUMO

BACKGROUND: Rabeprazole sodium is a proton pump inhibitor. AIM: To evaluate the efficacy and safety of 1-week triple therapy with rabeprazole, amoxycillin and clarithromycin for the eradication of Helicobacter pylori. METHODS: A total of 100 subjects with H. pylori were randomly divided into two groups of 1-week triple therapy with rabeprazole 10 mg b.d., amoxycillin 750 mg b.d. and either clarithromycin 200 mg b.d. (RAC400, n=50) or clarithromycin 400 mg b. d. (RAC800, n=50). Endoscopic examination with four biopsies (two specimens from the antrum and two from the gastric body) was performed. The status of H. pylori infection was determined using culture and histology (Giemsa stain) of the biopsy specimens. Sensitivity to clarithromycin was determined using the E-test: MIC > 8 g/mL was considered to be resistant, whereas MIC < 2 g/mL was considered to be sensitive. Cure was defined as no evidence of H. pylori infection 1 month after completion of treatment. RESULTS: There were no significant differences in the clinical characteristics of the two groups. Eradication rates (intention-to-treat and per protocol, respectively) were: RAC400: 86% (95% CI: 76-95%) and 89% (95% CI: 80-97%); RAC800: 94% (95% CI: 87-100%) and 97% (95% CI: 94-100%). There was no significant difference between the eradication rates of either regimen. Three subjects with failed eradication in the RAC400 group were all infected with a clarithromycin-resistant strain before beginning the therapy. Haemorrhagic colitis was the only severe adverse event, which was observed in one patient in the RAC800 group. CONCLUSION: One-week triple therapy with rabeprazole, amoxycillin and low-dose clarithromycin is effective for the eradication of H. pylori infection.


Assuntos
Amoxicilina/administração & dosagem , Antibacterianos/administração & dosagem , Antiulcerosos/administração & dosagem , Benzimidazóis/administração & dosagem , Claritromicina/administração & dosagem , Infecções por Helicobacter/tratamento farmacológico , Helicobacter pylori/efeitos dos fármacos , Penicilinas/administração & dosagem , 2-Piridinilmetilsulfinilbenzimidazóis , Adulto , Idoso , Amoxicilina/uso terapêutico , Antibacterianos/uso terapêutico , Antiulcerosos/uso terapêutico , Benzimidazóis/uso terapêutico , Claritromicina/uso terapêutico , Relação Dose-Resposta a Droga , Quimioterapia Combinada , Feminino , Infecções por Helicobacter/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Omeprazol/análogos & derivados , Penicilinas/uso terapêutico , Rabeprazol , Resultado do Tratamento
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