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1.
Aliment Pharmacol Ther ; 14(11): 1495-502, 2000 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11069321

RESUMO

BACKGROUND: The polymorphic enzyme CYP2C19 is of importance for the metabolism and effects of omeprazole during short-term treatment. AIM: To investigate the relationship between CYP2C19 genotype and the effects of long-term omeprazole treatment. MATERIAL AND METHODS: A total of 180 patients with acid related disorders were genotyped for wild type and mutated CYP2C19 alleles by allele-specific PCR amplification. Gastrin and chromogranin A were assessed by radioimmunoassays, and pepsinogen I and H. pylori serology were assessed by ELISA methods. RESULTS: In 108 of the patients, who received a single dose of 20 mg omeprazole, there was no difference in gastrin and chromogranin A concentrations between the three CYP2C19 genotypes. In 72 patients on long-term treatment (> 1 year) with 20 mg omeprazole daily, serum gastrin as well as plasma chromogranin A concentrations (mean +/- s.e.) were both about threefold higher in the wild type/mutated (52.1 +/- 7.6 pM and 7.3 +/- 1.3 nM (n=19), respectively) compared to wild type/wild type (14. 7 +/- 0.9 pM and 2.5 +/- 0.1 nM (n=52), respectively; both comparisons P=0.0001). In a single mutated/mutated patient on long-term treatment, both gastrin and chromogranin A were high (88 pM and 13.7 nM, respectively). Serum pepsinogen I concentration was significantly lower in wild type/mutated (n=19) patients on long-term treatment, compared with the corresponding wild type/wild type (n=49) group (147 +/- 19 microg/L vs. 193 +/- 12 microg/L, P=0. 04). CONCLUSION: Patients with one (and probably also with two) mutated CYP2C19 allele(s) on long-term treatment with omeprazole had significantly affected serum gastrin and pepsinogen I and plasma chromogranin A concentrations compared with patients with two normal alleles. This indicates that changes in gastric mucosal morphology during omeprazole treatment might be dependent upon the degree of the individual's capacity to metabolize omeprazole.


Assuntos
Antiulcerosos/uso terapêutico , Hidrocarboneto de Aril Hidroxilases , Biomarcadores Tumorais/sangue , Cromograninas/sangue , Sistema Enzimático do Citocromo P-450/genética , Gastrinas/sangue , Refluxo Gastroesofágico/tratamento farmacológico , Oxigenases de Função Mista/genética , Omeprazol/uso terapêutico , Pepsinogênio A/sangue , Cromogranina A , Citocromo P-450 CYP2C19 , Ensaio de Imunoadsorção Enzimática , Feminino , Mucosa Gástrica/efeitos dos fármacos , Mucosa Gástrica/metabolismo , Genótipo , Helicobacter pylori/isolamento & purificação , Humanos , Masculino , Pessoa de Meia-Idade , Úlcera Péptica/sangue , Úlcera Péptica/tratamento farmacológico , Polimorfismo Genético , Radioimunoensaio
2.
Gastroenterology ; 119(3): 670-6, 2000 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-10982760

RESUMO

BACKGROUND & AIMS: Omeprazole is metabolized by cytochrome P450 (CYP2C19). The activity of this enzyme is polymorphic, with incidences of poor metabolizers (PMs), heterozygous extensive metabolizers (EMs), and homozygous EMs in white populations of 3%, 30%, and 67%, respectively. The importance of the CYP2C19 polymorphism for the effects of omeprazole on intragastric pH and plasma gastrin concentrations has been investigated. METHODS: Twenty-five white patients were genotyped for CYP2C19 by allele-specific polymerase chain reaction amplification, and their Helicobacter pylori status was assessed by serology and with immunoblot analysis. Intragastric pH was monitored over 24 hours, and meal-stimulated plasma gastrin concentration was measured over 4 hours (AUC 4h) before (day 0) and during (day 8) treatment with 20 mg omeprazole once daily. RESULTS: Eleven patients were homozygous for the wild-type allele (wt/wt), 12 were heterozygous EMs (wt/mut), and 2 were PMs (mut/mut). Median (95% confidence interval) 24-hour intragastric pH in the heterozygous EM group was 5.5 (range, 5.1-5. 9) compared with 3.1 (range, 2.7-3.6) in homozygous EMs (P < 0.0001) at day 8. The percentage of time with intragastric pH > 4 at day 8 was significantly higher in the wt/mut than wt/wt group (72.4% vs. 37.1%; P < 0.0001). H. pylori status had less influence than CYP2C19 on intragastric acidity. Omeprazole treatment increased meal-stimulated plasma gastrin concentrations from day 0 to day 8 in the homozygous EMs and heterozygous EMs by 16% (NS) and 157% (P = 0. 002), respectively. In heterozygous EMs, the gastrin increase was more pronounced in the H. pylori-positive group (226%) than H. pylori-negative group (80%; P = 0.02). CONCLUSIONS: The effects of omeprazole on intragastric pH and plasma gastrin are dependent on the CYP2C19 polymorphism in patients with acid-related disorders.


Assuntos
Antiulcerosos/uso terapêutico , Hidrocarboneto de Aril Hidroxilases , Sistema Enzimático do Citocromo P-450/genética , Ácido Gástrico/metabolismo , Gastrinas/sangue , Oxigenases de Função Mista/genética , Omeprazol/uso terapêutico , Polimorfismo Genético/fisiologia , Idoso , Alelos , Citocromo P-450 CYP2C19 , Feminino , Genótipo , Helicobacter pylori/isolamento & purificação , Heterozigoto , Homozigoto , Humanos , Concentração de Íons de Hidrogênio , Masculino , Pessoa de Meia-Idade , Concentração Osmolar , Fenótipo , Gastropatias/tratamento farmacológico , Gastropatias/genética , Gastropatias/metabolismo , Gastropatias/microbiologia
4.
J Clin Endocrinol Metab ; 84(8): 2712-7, 1999 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10443665

RESUMO

Plasma chromogranin A (CgA) has been claimed to be a sensitive marker for neuroendocrine tumors, but its role in the early diagnosis of multiple endocrine neoplasia type 1 (MEN 1) pancreatic endocrine tumors has not been evaluated. We measured CgA in 36 patients with MEN 1, of whom 9 lacked pancreatic involvement, 20 had biochemical evidence of pancreatic endocrine tumors, and 7 displayed radiologically detectable pancreatic tumors. CgA was also analyzed in 25 patients with sporadic pancreatic endocrine tumors, 39 subjects with inflammatory bowel disease, 7 patients harboring nonendocrine pancreatic disease, and 19 healthy controls. Four of 9 of the MEN 1 patients without pancreatic involvement had elevated CgA. Furthermore, 60% with biochemically unequivocal tumors and all with a radiologically visible tumor showed elevations. All 25 patients with sporadic pancreatic endocrine tumor had increased CgA, as had 28% of patients with inflammatory bowel disease and 57% with nonendocrine pancreatic disease. Mean day to day CgA variation was 29% (range, 0-113%) in the neuroendocrine tumor patients and 21.0% (range, 0.0-47%, within reference range) among healthy controls. In summary, nonendocrine diseases may cause elevation of CgA, and its spontaneous variation can be considerable. Plasma chromogranin A is the most sensitive of the basal markers for neuroendocrine tumors, but cannot replace other established measures when screening for early pancreatic involvement in MEN 1.


Assuntos
Cromograninas/sangue , Neoplasia Endócrina Múltipla Tipo 1/sangue , Neoplasias Pancreáticas/sangue , Adulto , Idoso , Cromogranina A , Feminino , Humanos , Doenças Inflamatórias Intestinais/sangue , Masculino , Pessoa de Meia-Idade , Pancreatite/sangue
5.
Aliment Pharmacol Ther ; 13(4): 453-8, 1999 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10215728

RESUMO

BACKGROUND: The S-mephenytoin hydroxylase is a polymorphic cytochrome P450 (CYP) enzyme, identified as CYP2C19, which catalyses the metabolism of omeprazole and some other drugs. AIM: To determine whether long-term treatment with omeprazole affects serum vitamin B12 levels, and if so to what extent it depends on CYP2C19 activity. METHODS: Serum vitamin B12 levels (pmol/L) were assessed in 179 patients. Genotyping for wild-type (wt) and mutated (mut) CYP2C19 alleles was performed by allele-specific PCR amplification. RESULTS: One-hundred and eleven of the patients received one dose of 20 mg omeprazole. No difference in B12 levels were found between heterozygous (wt/mut) (n = 23) and homozygous (wt/wt) (n = 85) patients (mean +/- s.d., 350 +/- 82 vs. 315 +/- 87 pmol/L, respectively). Three patients were mut/mut, with serum vitamin B12 levels of 303 +/- 50 pmol/L. In the 68 patients on long-term (>1 year) therapy with 20 mg omeprazole daily, serum vitamin B12 levels were lower in the heterozygous (wt/mut) (n = 19) compared to homozygous wt/wt (n = 49) (246 +/- 71 vs. 305 +/- 98 pmol/L, P = 0. 01, respectively). In one patient (mut/mut) who was studied both after a single dose and after long-term (15 months) treatment with omeprazole, serum vitamin B12 decreased from 360 to 178 pmol/L. In the wt/mut, but not in the wt/wt group, serum vitamin B12 levels were significantly lower in patients on long-term therapy compared with those receiving one dose (246 +/- 71 vs. 350 +/- 82 pmol/L, P < 0.0001, respectively). CONCLUSIONS: CYP2C19 polymorphism significantly affected serum vitamin B12 levels in patients on long-term therapy with omeprazole. In the future, genotyping of CYP2C19 may be useful for patients in need of long-term treatment with omeprazole or other proton pump inhibitors.


Assuntos
Hidrocarboneto de Aril Hidroxilases , Inibidores das Enzimas do Citocromo P-450 , Inibidores Enzimáticos/farmacologia , Oxigenases de Função Mista/antagonistas & inibidores , Omeprazol/farmacologia , Vitamina B 12/sangue , Antiulcerosos/farmacologia , Antiulcerosos/uso terapêutico , Citocromo P-450 CYP2C19 , Sistema Enzimático do Citocromo P-450/genética , Sistema Enzimático do Citocromo P-450/metabolismo , Inibidores Enzimáticos/uso terapêutico , Esofagite/tratamento farmacológico , Esofagite/enzimologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Oxigenases de Função Mista/genética , Oxigenases de Função Mista/metabolismo , Omeprazol/uso terapêutico , Úlcera Péptica/tratamento farmacológico , Úlcera Péptica/enzimologia , Polimorfismo Genético
6.
Scand J Gastroenterol ; 34(2): 121-8, 1999 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10192187

RESUMO

BACKGROUND: Our aim was to evaluate which specific factors are of importance for the gastroesophageal reflux seen in presumably healthy subjects. METHODS: We investigated 57 healthy, asymptomatic volunteers with computer-aided medical history interrogation, endoscopy, biopsy specimens from the distal esophagus, manometry, and 24-h ambulatory pH-monitoring. RESULTS: Eight subjects (14%) claimed intermittent reflux symptoms at the computer interview, but they did not have more acid reflux at pH-monitoring than asymptomatic volunteers. Thirteen subjects (23%) had abnormalities at endoscopy, 3 of whom had an erosion in the distal esophagus, and 12 had hiatus hernia. Subjects with hiatus hernia had increased acid reflux at 24-h pH-monitoring compared with those without hernia. If subjects with hernia were excluded, the degree of acid reflux was similar in all age groups. Men had more acid reflux than women, and these differences persisted if subjects with hernia were excluded. There was no correlation of histologic signs of esophagitis in the distal esophagus, lower esophageal sphincter pressure, smoking habit, or body mass index with reflux of acid to the esophagus. CONCLUSION: Hiatus hernia is a common finding in healthy subjects, and it predisposes to gastroesophageal acid reflux. Histologic abnormalities are poorly related to acid reflux in healthy volunteers. We found increased acid reflux in healthy men compared with women, but larger studies are needed to confirm these findings. Symptom evaluation is not sufficient to exclude significant gastroesophageal reflux in healthy volunteers, and we suggest that the possibility of esophageal abnormalities should be excluded by endoscopy in comparative studies of gastroesophageal reflux disease.


Assuntos
Refluxo Gastroesofágico , Adulto , Biópsia , Esofagoscopia , Feminino , Refluxo Gastroesofágico/diagnóstico , Refluxo Gastroesofágico/patologia , Refluxo Gastroesofágico/fisiopatologia , Hérnia Hiatal , Humanos , Concentração de Íons de Hidrogênio , Masculino , Manometria , Pessoa de Meia-Idade , Monitorização Fisiológica , Fatores Sexuais , Estatísticas não Paramétricas
7.
Gastrointest Endosc Clin N Am ; 9(1): 37-59, 1999 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-9834316

RESUMO

Sonde-type enteroscopy has made it possible to potentially examine the entire depths of the small intestine. A relatively high diagnostic yield has been obtained by the sonde method in patients with obscure gastrointestinal bleeding. These features have made sonde enteroscopy a clinically accepted method. However, sonde-type enteroscopy has also some disadvantages making it less then a perfect endoscopy method. This article focuses on the technical aspects of sonde enteroscopy, but also summarizes the indications and the outcome of clinical studies.


Assuntos
Endoscopia Gastrointestinal , Enteropatias/diagnóstico , Intestino Delgado/patologia , Endoscópios Gastrointestinais , Tecnologia de Fibra Óptica , Humanos , Intubação Gastrointestinal/métodos
9.
Scand J Gastroenterol ; 33(10): 1034-8, 1998 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-9829356

RESUMO

BACKGROUND: Omeprazole is to a major extent metabolized by cytochrome P450 isozyme CYP2C19. The aims of this study were to compare the phenotype of CYP2C19 determined by omeprazole with the genotype and to determine the effect of Helicobacter pylori infection on the metabolism of omeprazole. METHODS: One-hundred and forty-three Caucasian patients with acid-related disorders assessed with a combination of gastrointestinal symptoms and upper endoscopic findings were given 20 mg omeprazole orally. Three hours after intake, omeprazole and 5-hydroxyomeprazole plasma concentrations were determined with high-performance liquid chromatography, and the phenotype for metabolic capacity was expressed as metabolic ratio (MR). Genotyping of defect alleles (CYP2C19*2 and *3) was performed by polymerase chain reaction amplification. One hundred eleven patients were tested after the first dose of omeprazole and 32 patients after repetitive administration (median time, 30 days). H. pylori serology was determined with enzyme-linked immunosorbent assay at the time of phenotyping. RESULTS: Genotypically, 2.8% had two mutated alleles and were poor metabolizers (PM), and 22.4% were heterozygous extensive metabolizers (EM). Among the 111 patients who received the first omeprazole dose, 4 patients had MR >5--that is, belonged to the PM phenotype. Two of these had PM genotype (both CYP2C19*2/*2), and two had an EM genotype (CYP2C19*11*1 and *1/*3), indicating that they have still unidentified mutations. In the heterozygous EM group the mean MR was higher in patients who had been on continued omeprazole treatment than in those given the first dose (5.7 versus 2.5, P = 0.02). There were no significant differences in MR and omeprazole concentrations between H. pylori-negative (43%) and -positive (57%) patients. CONCLUSION: In all but two patients with probable unidentified mutations there was agreement between the CYP2C19 phenotype determined by omeprazole and the genotype. The metabolism of omeprazole in patients with acid-related disorders is genetically determined and without relation to H. pylori infection.


Assuntos
Antiulcerosos/metabolismo , Hidrocarboneto de Aril Hidroxilases , Sistema Enzimático do Citocromo P-450/genética , Refluxo Gastroesofágico/enzimologia , Infecções por Helicobacter/enzimologia , Helicobacter pylori , Oxigenases de Função Mista/genética , Omeprazol/metabolismo , Úlcera Péptica/enzimologia , Antiulcerosos/uso terapêutico , Cromatografia Líquida de Alta Pressão , Citocromo P-450 CYP2C19 , Ensaio de Imunoadsorção Enzimática , Feminino , Refluxo Gastroesofágico/tratamento farmacológico , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Mutação , Omeprazol/uso terapêutico , Úlcera Péptica/tratamento farmacológico , Fenótipo , Reação em Cadeia da Polimerase
10.
J Clin Gastroenterol ; 27(2): 138-42, 1998 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-9754775

RESUMO

It has been suggested that profound acid inhibition by proton pump inhibitors affects the accuracy of H. pylori detection. This report aims to evaluate H. pylori status during treatment with four different invasive detection methods and to investigate if histopathological alterations during treatment can be used as an early marker for H. pylori eradication. Twenty-eight H. pylori-positive patients were studied randomized into two treatment groups: 14 patients received omeprazole, 20 mg plus amoxicillin 1,000 mg b.i.d (OA), and 14 patients received omeprazole, 20 mg and placebo b.i.d (OP) for 14 days. Biopsies from antrum and corpus of the stomach were collected on days 0, 10 and 42. H. pylori status was based on rapid urease test, cultivation, histology, and polymerase chain reaction (PCR). The biopsies were also graded according to the Sidney classification. In the OP and the OA group, 17% (2/12) and 92% (12/13) of the patients were H. pylori negative when tested during treatment (day 10). Four weeks after treatment none of the patients (0%) in the OP group and 61% (8/13) in the OA group had their H. pylori infection eradicated. PCR was up to 34% more sensitive than the other tests to detect H. pylori during treatment. There was a decrease in histological inflammation and activity in the antrum already during treatment in the OA group, but the decrease did not discriminate for successful treatment. During treatment with omeprazole alone or in combination with amoxicillin, H. pylori detection is impaired regardless of the detection method used. However, PCR appears to be more sensitive than other tests. Early changes in the histological appearance of the gastric mucosa do not predict H. pylori treatment outcome.


Assuntos
Gastrite/tratamento farmacológico , Infecções por Helicobacter/tratamento farmacológico , Helicobacter pylori/efeitos dos fármacos , Adulto , Idoso , Idoso de 80 Anos ou mais , Amoxicilina/administração & dosagem , Amoxicilina/efeitos adversos , Técnicas Bacteriológicas , Biópsia , Esquema de Medicação , Quimioterapia Combinada , Feminino , Seguimentos , Mucosa Gástrica/microbiologia , Mucosa Gástrica/patologia , Gastrite/microbiologia , Gastrite/patologia , Infecções por Helicobacter/microbiologia , Helicobacter pylori/isolamento & purificação , Humanos , Masculino , Pessoa de Meia-Idade , Omeprazol/administração & dosagem , Omeprazol/efeitos adversos , Reação em Cadeia da Polimerase , Valor Preditivo dos Testes
11.
Am J Physiol ; 274(6): G992-6, 1998 06.
Artigo em Inglês | MEDLINE | ID: mdl-9696722

RESUMO

Patients chronically infected with Helicobacter pylori are known to have hypergastrinemia. Previous studies have demonstrated the stimulation of gastrin from isolated G cells by monocytes and cytokines. The aim of this study was to determine if H. pylori can directly stimulate gastrin secretion. The secretion of gastrin from canine G cells in 48-h primary cultures was investigated using either live H. pylori bacteria or various bacterial extracts from three well-characterized strains. Whole bacterial sonic extracts and water-extracted surface proteins, but not PBS extracts, from strains 43579 (CagA+/VacA+), 60190 (CagA+/VacA+), and 60190:v1 (CagA+/VacA-) significantly stimulated gastrin release. Controls demonstrated that gastrin stimulation by the sonic extracts was not due to a direct toxic effect on G cells. We conclude that H. pylori produces a soluble factor(s), which can directly stimulate gastrin release in enriched canine G cell cultures. This stimulatory effect may play an important role in the H. pylori-associated hypergastrinemia and subsequent development of peptic ulcer disease.


Assuntos
Gastrinas/metabolismo , Helicobacter pylori/fisiologia , Antro Pilórico/metabolismo , Antro Pilórico/microbiologia , Animais , Proteínas de Bactérias/farmacologia , Células Cultivadas , Cães , Sonicação
12.
Eur J Surg ; 164(5): 345-52, 1998 May.
Artigo em Inglês | MEDLINE | ID: mdl-9667468

RESUMO

DESIGN: Retrospective study. SETTING: Teaching hospital, Sweden. OBJECTIVE: To find out if various diagnostic criteria could distinguish organic from non-organic causes of dyspepsia. SUBJECTS: 635 patients previously interviewed by computer questionnaire. INTERVENTIONS: Upper gastrointestinal endoscopy, laboratory tests, clinical examination. MAIN OUTCOME MEASURE: Differentiation between organic and functional dyspepsia. RESULTS: 106 patients had functional dyspepsia. Of these 83 had ulcer-like dyspepsia, 76 motility-like dyspepsia, and 50 reflux-like dyspepsia. Eight patients had unspecified dyspepsia. CONCLUSIONS: There was a considerable overlap between different subgroups, and the criteria did not differentiate between organic and non-organic causes of dyspepsia though the symptom criteria in most cases showed an independent value in discriminating between different subgroups. The clinical usefulness of the criteria remains to be shown.


Assuntos
Dispepsia/etiologia , Adulto , Diagnóstico por Computador , Diagnóstico Diferencial , Dispepsia/diagnóstico , Dispepsia/epidemiologia , Endoscopia Gastrointestinal , Feminino , Refluxo Gastroesofágico/complicações , Refluxo Gastroesofágico/diagnóstico , Motilidade Gastrointestinal , Humanos , Masculino , Úlcera Péptica/complicações , Úlcera Péptica/diagnóstico , Estudos Retrospectivos
13.
Scand J Gastroenterol ; 33(1): 39-43, 1998 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-9489906

RESUMO

BACKGROUND: The aim was to investigate whether intragastric pH, meal-stimulated gastrin release, or demographic factors predict the outcome of Helicobacter pylori treatment. METHODS: Thirty-six patients with H. pylori infection were investigated with 24-h intragastric pH registration and meal-stimulated gastrin release before and during treatment with 20 mg omeprazole twice daily and 750 mg amoxicillin twice daily for 14 days. The influence of age, sex, smoking, ethnic origin, pH, and gastrin on treatment outcome were analysed with logistic regression. RESULTS: Eradication of H. pylori was achieved in 18 of 34 (53%) patients. The univariate analysis showed that age, ethnic origin, more than 84.2% of the time with pH above 4, and continuous periods longer than 156 min with intragastric pH above 6 were significantly associated with successful treatment of H. pylori. In the multivariate analysis only the two pH variables were found to be independent factors for predicting treatment outcome. CONCLUSION: The outcome of H. pylori treatment with omeprazole and amoxicillin may depend on several factors, such as age, ethnic origin, and a pronounced acid suppression. However, the only factor of independent importance in this study was prolonged and profound acid inhibition.


Assuntos
Amoxicilina/uso terapêutico , Antiulcerosos/uso terapêutico , Infecções por Helicobacter/tratamento farmacológico , Helicobacter pylori , Omeprazol/uso terapêutico , Penicilinas/uso terapêutico , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Quimioterapia Combinada , Feminino , Infecções por Helicobacter/etnologia , Infecções por Helicobacter/microbiologia , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Bombas de Próton , Fatores Sexuais , Resultado do Tratamento
14.
Scand J Gastroenterol ; 33(12): 1239-43, 1998 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-9930385

RESUMO

BACKGROUND: Lansoprazole (LAN) and omeprazole (OME) heal esophagitis effectively and to similar extents, but LAN has a faster effect on the relief of symptoms of gastroesophageal reflux. However, no strict comparison of the two proton pump inhibitors' effect on acid reflux and gastric acidity has been published. The aim of this study was to compare the effects of LAN and OME on gastroesophageal reflux with simultaneous measurements of gastric acidity in patients with established gastroesophageal reflux disease (GERD) and esophagitis. METHODS: Fourteen patients with endoscopically verified erosive esophagitis and with a pretreatment esophageal 24-h pH measurement showing acid reflux to the esophagus participated in the study. This was a double-blind, randomized study with crossover design. Before (day 0) and on the last day (day 5) of each treatment period with encapsulated 30 mg LAN or 20 mg OME daily, 24-h intraesophageal and intragastric acidity were measured with antimony electrodes connected to an ambulatory pH recording system. RESULTS: Ten of 14 patients completed the study. There were no differences in intragastric or intraesophageal acidity or the number of reflux episodes on day 0 between the two treatments. Both LAN and OME treatments increased the median and nocturnal intragastric pH and decreased the 24-h area under the time curve for intragastric acidity significantly and to about the same extent (79% and 69% acid inhibition by LAN and OME, respectively) (NS). However, the percentage of time with pH below 4 in the esophagus was significantly less during LAN treatment (1.92% +/- 2.29; mean +/- standard deviation) than during OME treatment (4.76% +/- 2.88%) on day 5 (P = 0.002). There were also significantly fewer reflux episodes >5 min during treatment with LAN (1.00 +/- 1.33) than with OME (2.90 +/- 2.42) at the end of the treatment period (P = 0.031). CONCLUSIONS: In this study lansoprazole and omeprazole had a comparable effect on gastric acidity in patients with established GERD with esophagitis. However, 30 mg lansoprazole daily reduced the acidity in the oesophagus and the number of refluxes more effectively than 20 mg omeprazole daily. This might indicate that proton pump inhibitors affect the esophageal clearance and/or influence the lower esophageal sphincter differently.


Assuntos
Refluxo Gastroesofágico/tratamento farmacológico , Fármacos Gastrointestinais/uso terapêutico , Omeprazol/análogos & derivados , Omeprazol/uso terapêutico , Inibidores da Bomba de Prótons , 2-Piridinilmetilsulfinilbenzimidazóis , Adulto , Idoso , Estudos Cross-Over , Método Duplo-Cego , Esofagite/tratamento farmacológico , Esofagite/metabolismo , Feminino , Ácido Gástrico/metabolismo , Refluxo Gastroesofágico/metabolismo , Humanos , Concentração de Íons de Hidrogênio , Lansoprazol , Masculino , Pessoa de Meia-Idade
15.
J Clin Invest ; 100(5): 1037-46, 1997 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-9276720

RESUMO

Isolated canine G cells in primary culture have been used to study calcium, protein kinase C (PKC), and rho/cytoskeletal-dependent intracellular pathways involved in bombesin- stimulated gastrin release. A method to obtain highly purified G cells by culture (64% G cells) after flow cytometry on elutriated fractions of cells from digested canine gastric antral mucosa has been developed. Pretreatment of G cells with thapsigargin (10(-8)-10(-6) M) and release experiments in Ca2+-containing or -depleted media showed that influx of Ca2+ into the cells and not acute release from intracellular stores plays an important role in bombesin-stimulated gastrin release. Inhibition of PKC by the specific inhibitor GF 109 203X did not affect bombesin-stimulated release. Rho, a small GTP-binding protein that regulates the actin cytoskeleton, is specifically antagonized by Clostridium botulinum C3 exoenzyme. C3 (10 microg/ml) enhanced basal and bombesin-stimulated gastrin release by 315 and 266%, respectively. The importance of the cytoskeleton for regulation of gastrin release was emphasized by a more pronounced release of gastrin when the organization of the actin cytoskeleton was disrupted by cytochalasin D (5 x 10(-)7 and 10(-)6 M). Wortmannin, a potent inhibitor of phosphoinositide-3-kinase, did not alter bombesin-stimulated gastrin release. Thus, it is concluded that bombesin-induced gastrin release from canine G cells is stimulated by Ca2+ but not by PKC, and is enhanced by disruption of rho/cytoskeletal pathways.


Assuntos
Bombesina/farmacologia , Toxinas Botulínicas , Cálcio/fisiologia , Citoesqueleto/fisiologia , Mucosa Gástrica/efeitos dos fármacos , Gastrinas/metabolismo , Proteína Quinase C/fisiologia , Fator Rho/fisiologia , ADP Ribose Transferases/farmacologia , Animais , Citocalasina D/farmacologia , Cães , Citometria de Fluxo , Mucosa Gástrica/metabolismo , Acetato de Tetradecanoilforbol/farmacologia
16.
Scand J Gastroenterol ; 32(7): 669-75, 1997 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-9246706

RESUMO

BACKGROUND: Studies in different species have suggested, but not established, that sex hormones influence gastric acid secretion. We studied how acid output is affected by the sex hormones estradiol or testosterone in vivo and in vitro. METHODS: In gastric fistula rats that were normal, sham-operated, neonatally gonadectomized, or treated with estradiol or testosterone, 24-h basal and pentagastrin-stimulated acid secretion was measured. The in vitro effects of estradiol and testosterone on histamine-induced aminopyrine accumulation in isolated parietal cells were also determined. RESULTS: Basal acid output was similar in the two sexes, but stimulated secretion was significantly higher (34%; P < 0.01) in males. Ovariectomy did not influence acid output, whereas orchidectomy reduced basal (18%; NS) and stimulated 24-h secretion (P < 0.01). Estradiol decreased (23%; NS) the 24-h basal output in females but not in males. Estradiol suppressed stimulated secretion in females (29%, P < 0.01) and males (42%, P < 0.01) during the day. At night the stimulated secretion increased in both females (17%, NS) and males (32%, P < 0.05). A similar pattern was found when rats were treated with testosterone. In vitro, estradiol and testosterone reduced histamine-stimulated aminopyrine accumulation in both female and male isolated parietal cells. CONCLUSIONS: Estradiol and testosterone both appear to influence gastric secretion in rats, and their action differs between day and night, between the sexes, and between basal and stimulated secretion.


Assuntos
Estradiol/fisiologia , Ácido Gástrico/metabolismo , Testosterona/farmacologia , Aminopirina , Animais , Castração , Ritmo Circadiano/fisiologia , Estradiol/farmacologia , Feminino , Fístula Gástrica/fisiopatologia , Masculino , Células Parietais Gástricas/fisiologia , Pentagastrina , Ratos , Ratos Sprague-Dawley , Caracteres Sexuais , Fatores de Tempo
17.
J Biol Chem ; 272(14): 9037-42, 1997 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-9083028

RESUMO

Cholecystokinin (CCK)-A and CCK-B receptors are highly homologous members of the seven transmembrane domain G-protein-coupled receptor superfamily. Genes of both receptors contain five exons and share a similar exon-intron organization. To determine the structural basis of CCK-A receptor (CCK-AR) functionally coupled to Gs, a series of chimeric mutants were constructed by replacing exons of human CCK-B receptor (CCK-BR), from the second to the fifth (last) exon, with human CCK-AR counterparts. Binding and signal transduction properties of wild-type and chimeric receptors were examined in stably transfected HEK-293 cells. Chimeric receptors that maintained high affinity binding to CCK exhibited dose-dependent increases in intracellular calcium mobilization similar to both wild-type receptors. However, only the wild-type CCK-AR and chimeric mutants containing the second exon of CCK-AR were able to mediate significantly greater increases in intracellular cAMP content and adenylyl cyclase activity compared with wild-type CCK-BR. A CCK-BR mutant was further constructed by replacing five amino acids, Gly-Leu-Ser-Arg-(Arg)-Leu, in the first intracellular loop with the corresponding five CCK-AR specific amino acids, Ile-Arg-Asn-Lys-(Arg)-Met. The resultant receptor maintained high affinity binding to both CCK and gastrin and dose-dependent calcium responses similar to wild-type CCK-BR. However, this first intracellular loop mutant also gained positive cAMP responses to both sulfated CCK-8 and gastrin-17 with EC50 values of 8.5 +/- 1 nM and 23 +/- 7 nM, respectively. These data suggest that the first intracellular loop of CCK-AR is essential for coupling to Gs and activation of adenylyl cyclase signal transduction cascade.


Assuntos
AMP Cíclico/metabolismo , Subunidades alfa Gs de Proteínas de Ligação ao GTP/metabolismo , Receptores da Colecistocinina/metabolismo , Transdução de Sinais , Adenilil Ciclases/metabolismo , Linhagem Celular , Relação Dose-Resposta a Droga , Ativação Enzimática , Gastrinas/administração & dosagem , Gastrinas/metabolismo , Humanos , Cinética , Conformação Proteica , Receptor de Colecistocinina A , Receptores da Colecistocinina/química , Proteínas Recombinantes de Fusão/química , Proteínas Recombinantes de Fusão/metabolismo , Sincalida/administração & dosagem , Sincalida/metabolismo , Relação Estrutura-Atividade , Transfecção
18.
Scand J Clin Lab Invest ; 57(8): 689-94, 1997 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-9458491

RESUMO

The urea breath test (UBT) has been shown to be a reliable non-invasive method for detection of H. pylori infection. There is widespread use of a test meal in the 13C UBT, but to what extent exclusion of the test meal actually influences the accuracy of the test has been poorly investigated. In addition, there is variability between test protocols in breath sampling frequency. In this evaluation, 91 patients with dyspeptic symptoms were investigated in an out-patient endoscopy ward, using a simplified 13C UBT without a test meal, and a single point breath evaluation after ingestion of 13C-labelled urea. Helicobacter pylori infection was diagnosed on upper endoscopy by histology and rapid urease tests on biopsies from the antrum and corpus mucosa of the stomach. Fifty-four percent of the patients had H. pylori infection. With the chosen cut-off level, the sensitivity and specificity of the 13C UBT were 92% and 95%, respectively. We conclude that this simplified 13C UBT is easy to perform and a very reliable test for detecting H. pylori infection, making it a suitable test in routine clinical work.


Assuntos
Testes Respiratórios , Infecções por Helicobacter/diagnóstico , Helicobacter pylori , Ureia/análise , Adulto , Idoso , Idoso de 80 Anos ou mais , Isótopos de Carbono , Dispepsia/microbiologia , Alimentos , Mucosa Gástrica/microbiologia , Helicobacter pylori/isolamento & purificação , Humanos , Pessoa de Meia-Idade , Úlcera Péptica/microbiologia , Sensibilidade e Especificidade , Urease
19.
J Antimicrob Chemother ; 38(6): 927-39, 1996 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-9023640

RESUMO

Fourteen patients with Helicobacter pylori infection were treated with omeprazole capsules 20 mg and amoxycillin capsules 1000 mg twice daily for 14 days and 14 patients with omeprazole capsules 20 mg and placebo twice daily for 14 days. Samples from saliva, dental plaque and faeces and biopsies from antrum and corpus were analysed in order to determine the ecological changes in the normal microflora. Several microorganisms were affected by both treatment regimens. Two patients were colonised with enterobacteria in the oral cavity and stomach during the omeprazole plus amoxycillin treatment. A general increase in the number of microorganisms from gastric mucosa was observed in both treatment groups. A selection of resistant enterobacteria and an increase in beta-lactamase production was observed in the faecal samples during the omeprazole plus amoxycillin treatment. Eradication of H. pylori in the omeprazole-amoxycillin group was 50% and in the omeprazole placebo group 0% four weeks after treatment. No viable H. pylori were cultivated in the saliva, dental plaque or faecal samples. Treatment with omeprazole 20 mg and amoxycillin 1000 mg twice daily for 14 days altered the normal microflora in the oral, gastric and intestinal tract and antibiotic resistant microorganisms increased in numbers in the intestinal microflora.


Assuntos
Amoxicilina/farmacologia , Antiulcerosos/farmacologia , Infecções por Helicobacter/tratamento farmacológico , Infecções por Helicobacter/microbiologia , Helicobacter pylori , Intestinos/efeitos dos fármacos , Intestinos/microbiologia , Boca/efeitos dos fármacos , Boca/microbiologia , Omeprazol/farmacologia , Penicilinas/farmacologia , Estômago/efeitos dos fármacos , Estômago/microbiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Biópsia , Placa Dentária/microbiologia , Método Duplo-Cego , Quimioterapia Combinada , Fezes , Feminino , Mucosa Gástrica/efeitos dos fármacos , Mucosa Gástrica/microbiologia , Humanos , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Placebos , Reação em Cadeia da Polimerase , Saliva/efeitos dos fármacos , Saliva/microbiologia , beta-Lactamases/metabolismo
20.
J Clin Gastroenterol ; 23(2): 145-51, 1996 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-8877646

RESUMO

Malignant transformation in bile duct hamartomas has been previously reported in very rare instances. Here, we describe a unique case of a neuroendocrine tumor of the liver arising within an area of unusually large hamartoma with predominant bile duct component, hitherto unreported and distinct from the conventional von Meyenburg complex. The tumor was apparently secreting gastrin and chromogranin, with associated gastrinoma syndrome over several years. The histologic picture was reminiscent of a moderately differentiated adenocarcinoid, with positive mucin staining in a signet ring pattern. Tumor cells showed positive staining for neuron-specific enolase, chromogranin A, gastrin, and serotonin. Staining for pancreatic hormone peptides was negative. Resection of the tumor was apparently curative, with complete resolution of the patient's symptoms.


Assuntos
Doenças dos Ductos Biliares/complicações , Doenças dos Ductos Biliares/patologia , Tumor Carcinoide/diagnóstico por imagem , Hamartoma/complicações , Hamartoma/patologia , Hepatopatias/complicações , Hepatopatias/patologia , Neoplasias Hepáticas/etiologia , Neoplasias Hepáticas/patologia , Doenças dos Ductos Biliares/diagnóstico por imagem , Tumor Carcinoide/química , Tumor Carcinoide/patologia , Cromogranina A , Cromograninas/análise , Feminino , Gastrinas/análise , Hamartoma/química , Hamartoma/diagnóstico por imagem , Humanos , Imuno-Histoquímica , Hepatopatias/diagnóstico por imagem , Neoplasias Hepáticas/química , Neoplasias Hepáticas/diagnóstico por imagem , Imageamento por Ressonância Magnética , Pessoa de Meia-Idade , Cintilografia , Tomografia Computadorizada por Raios X
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