RESUMO
Gastric nitrite content was studied in relation to precancerous lesions of the stomach in a case-control study conducted in a high-risk Colombian population. The proportion of detectable nitrite in gastric juice and the mean pH were significantly higher among those with precancerous lesions (chronic atrophic gastritis, intestinal metaplasia, and dysplasia) than among the controls (normal and superficial gastritis); the proportion and mean pH increased with the progression of histological changes from normal to dysplasia. Nitrite was not detectable in gastric juice with a pH less than 5.0. A positive association was found between the proportion of detectable nitrite and the risk of gastric precancerous lesions. Odds ratios of 4.39 for intestinal metaplasia and 24.72 for dysplasia remained significant after controlling for confounders. This finding suggests that nitrite may be a precursor of a mutagen that targets gastric epithelial cells.
Assuntos
Nitratos/efeitos adversos , Nitritos/análise , Lesões Pré-Cancerosas/etiologia , Neoplasias Gástricas/etiologia , Estudos de Casos e Controles , Estudos de Coortes , Colômbia/epidemiologia , Feminino , Suco Gástrico/análise , Gastrite/metabolismo , Humanos , Masculino , Fatores de Risco , Neoplasias Gástricas/epidemiologiaRESUMO
Sucrogel H-70, a recently synthesized polyester of sucrose, was investigated as a potential drug delivery matrix. In this study, the release of sodium salicylate was examined from a reservoir-controlled release device. It is shown that sodium salicylate release follows zero-order kinetics in the three media studied (i.e., water and simulated gastric and intestinal fluids).
Assuntos
Salicilatos/análise , Líquidos Corporais/análise , Química Farmacêutica , Preparações de Ação Retardada , Suco Gástrico/análise , Géis , Intestinos/análise , Polímeros , Salicilatos/administração & dosagem , Ácido Salicílico , SacaroseRESUMO
Increased duodenogastric reflux has been recognized as a cause of gastric mucosa damage. The frequent finding of bile-stained gastric juice and a suggested higher frequency of lesions of the gastric mucosa in patients with Chagas' disease, which is characterized by a marked reduction of myenteric neurons, suggest that impairment of intrinsic innervation of the gut might be associated with increased duodenogastric reflux. Duodenogastric bile reflux was quantified after intravenous injection of 99mtechnetium-HIDA, in 18 patients with chronic Chagas' disease, 12 controls, and 7 patients with Billroth II gastrectomy. All but one of the chagasic patients were submitted to upper digestive tract endoscopy. High reflux values (greater than or equal to 10%) were detected both in chagasic patients and in the controls, but the values for both groups were significantly lower (P less than 0.01) than those obtained for Billroth II patients (median: 55.79%; range: 12.58-87.22%). Reflux values tended to be higher in the Chagas' disease group (median: 8.20%; range: 0.0-29.40%) than in the control group (median: 3.20%; range: 0.0-30.64%), with no statistical difference between the two groups (P greater than 0.10). Chronic gastritis was detected by endoscopy in 12 chagasic patients, benign gastric ulcer in 2 patients, and a pool of bile in the stomach in 11 patients. However, neither the occurrence of gastric lesions nor the finding of bile-stained gastric juice was associated with high reflux values after [99mTc]HIDA injection. This study suggests that lesions of the intramural nervous system of the gut in Chagas' disease do not appear to be associated with abnormally increased duodenogastric reflux.
Assuntos
Doença de Chagas/complicações , Refluxo Duodenogástrico/complicações , Adulto , Bile/análise , Feminino , Gastrectomia/efeitos adversos , Suco Gástrico/análise , Gastroscopia , Humanos , Iminoácidos , Masculino , Pessoa de Meia-Idade , Gastropatias/etiologia , TecnécioRESUMO
The effects of chronic alcoholism upon the parietal cells of the stomach of rats were studied providing to a group of animals, only sugar cane brandy "ad libitum" as liquid food. A group of control animals received tap water and to both groups it was provided a balanced solid diet. During the experiment the body weight as well as liquid and solid food consumption were rated each other day. The animals were sacrificed after 45, 90 or 180 d and the effects of alcoholism evaluated at the day of sacrifice through morphological and morphometric techniques. Our results allowed us to conclude that: 1) the body weight of alcohol-treated animals increased at much slower rates when compared to controls. (2) The treated animals ingested less liquid and solid food than controls. 3) The volume of gastric secretion (ml/h/100 g of body weight) was not affected but its HCl content (mEq/l) was smaller in alcoholic rats. 4) Discrete morphological disturbance of the gastric mucosa was observed only in animals that ingested alcohol for 45 d. In the longer treatments the appearance of the mucosa was quite similar to controls. 5) The secreting mass of parietal cells decreased in alcohol treated rats. This decrease was attributed to a reduction in number of these cells.
Assuntos
Alcoolismo/patologia , Células Parietais Gástricas/patologia , Animais , Peso Corporal , Ingestão de Líquidos , Ingestão de Alimentos , Suco Gástrico/análise , Suco Gástrico/metabolismo , Mucosa Gástrica/metabolismo , Mucosa Gástrica/patologia , Ácido Clorídrico/análise , Masculino , Microscopia Eletrônica , Células Parietais Gástricas/ultraestrutura , Ratos , Ratos EndogâmicosRESUMO
The etiological model of gastric carcinogenesis is discussed. Its complexity and flexibility may be more applicable to human situations than experimental models utilizing high doses of carcinogens in homogeneous animal populations. The limitations of the epidemiological method and the use of a collaborative approach by epidemiologists and experimentalists are described. The need for markers of exposure to N-nitroso compounds is stressed.
Assuntos
Compostos Nitrosos , Neoplasias Gástricas/induzido quimicamente , Animais , Biotransformação , Colômbia , Dieta/efeitos adversos , Métodos Epidemiológicos , Determinação da Acidez Gástrica , Suco Gástrico/análise , Mucosa Gástrica/efeitos dos fármacos , Mucosa Gástrica/patologia , Humanos , Louisiana , Nitratos/análise , Nitritos/análise , Compostos Nitrosos/análise , Neoplasias Gástricas/etiologiaRESUMO
Em 50 pacientes determinou-se o pH do suco gástrico após doses seqüenciais de cimetidine, administrada por via intramuscular e intravenosa. Os valores obtidos demonstram que a droga, administrada por essas vias, näo atinge níveis terapêuticos, sendo a via intravenosa a única realmente eficaz. Esta eficácia, todavia, só é uniforme entre a segunda e a quarta horas após o estímulo. Dois pacientes näo tiveram seu pH intragástrico aumentado mesmo após o emprego de doses elevadas. A administraçäo a intervalos de seis horas produz com freqüência uma curva de pH em "S" e deve ser usada somente em casos selecionados, com monitoraçäo da acidez gástrica. O emprego a intervalos de quatro horas provavelmente oferece melhor proteçäo contra lesöes agudas da mucosa gástrica, pépticas ou näo pépticas
Assuntos
Lactente , Pré-Escolar , Criança , Adolescente , Humanos , Masculino , Feminino , Cimetidina/administração & dosagem , Suco Gástrico/análise , Concentração de Íons de HidrogênioRESUMO
Em 30 pacientes, submetidos à anestesia raquídica, para cirurgias eletivas, foi colhida, previamente, amostra de líquor, para a verificaçäo do pH e valor da glicose, além da amostra de sangue arterial, com idêntica finalidade. Também foi colhida amostra de suco gástrico, em todos os pacientes, a fim de se verificar o valor do pH. Os valores obtidos, para o pH e glicose do líquor e sangue arterial, foram agrupados em tabelas e submetidos à análise estatística, com base no teste "t" de Student, adotando-se, como nível de significância, p < 0,05. As médias globais foram para o líquor: pH = 7,38 (7,13 a 8,50) e glicose = 62,60 (42 a 89) mg%; para o sangue arterial: pH = 7,34 (7,20 a 7,42) e glicose = 86 (68) a 130) mg% e para o suco gástrico: pH = 2,03 (1 a 5). O valor médio da relaçäo glicorraquia/glicemia foi 0,73 (0,46 a 0,92). Considerando que, em pacientes pediátricos, os valores médios dos parâmetros estudados säo escassos na literatura médica, achamos importante um trabalho desta natureza
Assuntos
Recém-Nascido , Lactente , Pré-Escolar , Criança , Humanos , Raquianestesia , Glucose/líquido cefalorraquidiano , Concentração de Íons de Hidrogênio , Suco Gástrico/análiseRESUMO
We designed an in vitro assay to detect the presence of lactose in the tracheal aspirates of premature, ventilator-dependent infants. This method was employed to identify recurrent, unrecognized aspiration, which could prolong the requirements for ventilator support and contribute to the development of chronic lung disease. One hundred five determinations of lactose were performed on the tracheal fluid obtained from 42 ventilator-dependent infants who were receiving enteral feedings. There was a wide range of lactose levels (0 to 3,270 nmol lactose/ml tracheal aspirate). Six infants had samples that were highly suggestive of aspiration (greater than 200 nmol lactose/ml tracheal aspirate). Twenty infants had questionably positive samples (25 to 200 nmol lactose/ml tracheal aspirate), and 16 infants had samples that were considered negative for aspiration (less than 25 nmol lactose/ml tracheal aspirate).