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PubMed2004

[Clinical analysis of 61 patients with antiphospholipid syndrome].

OBJECTIVE: To investigate the clinical manifestations, diagnosis and treatment of anti-phospholipid syndrome (APS). METHODS: 61 patients with defined APS admitted from Jan 1986 to Dec 2002 were analyzed retrospectively. RESULTS: 10 patients with primary APS and 51 patients with secondary APS were analyzed. Women were affected 3.1 times as that of men. 48 of the 51 (94.1%) patients with secondary APS were complicated with other autoimmune diseases, including 33 cases (64.7%) of systemic lupus erythematosus. Vascular thrombosis was presented in around 80.3% of the patients in this study. Thrombosis frequently involved the gastrointestinal system (21 cases, 22.6%), pulmonary system (19 cases, 20.4%), the cerebral vascular system (17 cases, 18.3%), lower limb deep venous system (16 cases, 17.2%), and infrequently coronary arteries or adrenal glands. The abnormal pregnancy rate in the 37 married women was 45.9%. The prevalence of anticardiolipin antibody (ACL) and lupus anticoagulant (LA) was 77.0% and 62.3% respectively. LA was associated with ACL. CONCLUSION: APS occurs most commonly among young women, is a disorder characterized by recurrent venous or arterial thrombosis and/or fetal losses associated with positive ACL or LA. Thrombosis frequently occurs in gastrointestinal system, pulmonary system, cerebral vascular system and deep venous system. The association between clinical features of APS and antiphospholipid antibody is significant. LA is a stronger risk factor for thrombosis and abnormal pregnancy than ACL. Antiplatelet with low-dosage aspirin and long-term anticoagulation are main therapeutics.

Adult↗
PubMed2003

Gastrointestinal and systemic uptake of bismuth in mice after oral exposure.

Bismuth compounds have been used in medicine for more than 200 years. In recent years, bismuth has gained renewed interest as a remedy for eradication of gastrointestinal pathogens, especially Helicobacter pylori. In this study we describe the anatomical distribution of bismuth in the gastrointestinal tract and other organs after oral exposure in a mouse model. After exposure of the experimental animals to ranitidine bismuth citrate or bismuth citrate, we used the autometallographic silver enhancement technique to demonstrate the presence of bismuth in tissue samples from the gastrointestinal tract, liver, spleen, thymus, kidney and lymph nodes. We exposed cultured murine peritoneal macrophages to bismuth citrate and examined the bismuth accumulation over time. We found that in the mouse bismuth is absorbed systemically after a single dose of either compound, ranitidine bismuth more easily than bismuth citrate. Uptake could be shown in the stomach, duodenum, ileum and kidney for hours after exposure. Weeks after the exposure, deposits of bismuth were found in lymph nodes, liver, spleen and kidney as well as in macrophages in the gastrointestinal lamina propria. At the subcellular level, bismuth was found exclusively in lysosomes, primarily in macrophages and dendritic cells. Subsequent analyses of macrophage cultures showed lysosomal accumulations to be time and dose dependent.

Absorption↗
PubMed2004

Regulation of the cellular and physiological effects of glutamine.

Glutamine is the most abundant amino acid in humans and possesses many functions in the body. It is the major transporter of amino-nitrogen between cells and an important fuel source for rapidly dividing cells such as cells of the immune and gastrointestinal systems. It is important in the synthesis of nucleic acids, glutathione, citrulline, arginine, gamma aminobutyric acid, and glucose. It is important for growth, gastrointestinal integrity, acid-base homeostasis, and optimal immune function. The regulation of glutamine levels in cells via glutaminase and glutamine synthetase is discussed. The cellular and physiologic effects of glutamine upon the central nervous system, gastrointestinal function, during metabolic support, and following tissue injury and critical illness is also discussed.

Animals↗
PubMed1999

Cell proliferation in gastrointestinal mucosa.

Gastrointestinal cell proliferation plays an important role in the maintenance of the integrity of the gastrointestinal system. The study of gastrointestinal proliferation kinetics allows a better understanding of the complexity of the system, and also has important implications for the study of gastrointestinal carcinogenesis. Gastrointestinal stem cells are shown to be pluripotential and to give rise to all cell lineages in the epithelium. Carcinogenesis in the colon occurs through sequential mutations, possibly occurring in a single cell--the stem cell.

Cell Division↗
PubMed2004

Minireview: Diversity and complexity of signaling through peptidergic G protein-coupled receptors.

The transmission of signals by G protein-coupled receptors (GPCRs) that use peptides as ligands is critical for function of the gastrointestinal system. Molecular cloning has indicated that GPCRs constitute the most diverse transmembrane receptor family with many of these genes expressed in the gastrointestinal system. In addition to this molecular diversity, it has become clear that signaling through GPCRs is highly complex, with a wide variety of mechanisms that underlie different signaling responses and pathways through the same receptor. This minireview will summarize some of the emerging concepts of peptidergic GPCRs: signaling diversity including coupling to different G proteins, multiple endogenous ligands that can mediate different effects through binding to their cognate receptors, and homo- and hetero-oligomerization of receptors to enable cross talk or to produce novel signaling units.

Animals↗
PubMed2006

Biocompatibility of a lab-on-a-pill sensor in artificial gastrointestinal environments.

In this paper, we present a radiotelemetry sensor, designed as a lab-in-a-pill, which incorporates a two-channel microfabricated sensor platform for real-time measurements of temperature and pH. These two parameters have potential application for use in remote biological sensing (for example they may be used as markers that reflect the physiological environment or as indicators for disease, within the gastrointestinal tract). We have investigated the effects of biofouling on these sensors, by exploring their response time and sensitivity in a model in vitro gastrointestinal system. The artificial gastric and intestinal solutions used represent a model both for fasting, as well as for the ingestion of food and subsequent digestion to gastrointestinal chyme. The results showed a decrease in pH sensitivity after exposure of the sensors for 3 h. The response time also increased from an initial measurement time of 10 s in pure GI juice, to ca. 25 s following the ingestion of food and 80 s in simulated chyme. These in vitro results indicate that changes in viscosity in our model gastrointestinal system had a pronounced effect on the unmodified sensor.

Biocompatible Materials↗
PubMed1999

Stress-induced changes in the gastrointestinal motor system.

Several autonomic, hormonal, behavioural and neuropeptidergic bodily responses to stressful stimuli have been described over the past few decades. Both animal models and human paradigms have been explored. It is acknowledged that stress modulates gastrointestinal (GI) motility through central mechanisms including corticotropin-releasing-factor. This process requires the integrity of autonomic neural pathways. It has become evident that the effects of stress on GI motility vary according to the stressful stimulus, its intensity, the animal species under study and the time course of the study. Recent evidence suggests that chronic or possibly permanent changes develop in enteric smooth muscle properties in response to stress. In animals, the most consistent findings include retardation of gastric emptying in response to various stressors; acceleration of gastric emptying upon cold stress, presumably through the secretion of brain thyroglobulin-hormone; acceleration of intestinal transit; and stimulation of colonic transit and fecal output. In humans, the cold water immersion test has been associated with an inhibition of gastric emptying, while labyrinthine stimulation induces the transition from postprandial to fasting motor patterns in the stomach and the small bowel. Psychological stress has been shown to induce a reduction in the number and amplitude of intestinal migrating motor complexes and to neither affect nor stimulate colonic motility. These various responses to stress are presumably attributed to the preferential activation of specific neuronal pathways under the influence of a given stimulus or its intensity. The significance of these findings and the directions of further studies are discussed.

Animals↗
PubMed2002

Deterioration of drinking water quality in the distribution system and gastrointestinal morbidity in a Russian city.

Few studies have been conducted in Russia to assess the relationship between drinking water quality and gastrointestinal (GI) infections. In the city of Cherepovets, effluent water at the treatment plant usually meets the country's hygienic standards. To provide protection against secondary water contamination in the distribution system, concentrations of total residual chlorine in effluent water are maintained#10; at levels from 1 to 2 mg x l(-1). However, residual chlorine concentrations rapidly decline in the distribution system and rechlorination is not practiced. Some areas of the city routinely have very low residual chlorine at taps and little protection against secondary microbiological contamination of water in pipelines. A cross-sectional epidemiological study was conducted in Cherepovets to assess an association between decline in residual chlorine concentrations and risk of GI illness. This study included water quality monitoring and an extensive questionnaire survey of city residents. The results demonstrated a consistent spatial pattern of free chlorine decline in the distribution system. An interquartile range variability in free residual chlorine decline (0.22 mg x l(-1)) was associated with 1.42 (95% confidence interval (CI) = 1.05, 1.91) relative risk of self-reported gastrointestinal illness after control for socioeconomic, hygienic and demographic parameters.

Adolescent↗
PubMed2003

Chemical coding of the human gastrointestinal nervous system: cholinergic, VIPergic, and catecholaminergic phenotypes.

The aim of this investigation was to identify the proportional neurochemical codes of enteric neurons and to determine the specific terminal fields of chemically defined nerve fibers in all parts of the human gastrointestinal (GI) tract. For this purpose, antibodies against the vesicular monoamine transporters (VMAT1/2), the vesicular acetylcholine transporter (VAChT), tyrosine hydroxylase (TH), dopamine beta-hydroxylase (DBH), serotonin (5-HT), vasoactive intestinal peptide (VIP), and protein gene product 9.5 (PGP 9.5) were used. For in situ hybridization (35)S-labeled VMAT1, VMAT2, and VAChT riboprobes were used. In all regions of the human GI tract, 50-70% of the neurons were cholinergic, as judged by staining for VAChT. The human gut unlike the rodent gut exhibits a cholinergic innervation, which is characterized by an extensive overlap with VIPergic innervation. Neurons containing VMAT2 constituted 14-20% of all intrinsic neurons in the upper GI tract, and there was an equal number of TH-positive neurons. In contrast, DBH was absent from intrinsic neurons. Cholinergic and monoaminergic phenotypes proved to be completely distinct phenotypes. In conclusion, the chemical coding of human enteric neurons reveals some similarities with that of other mammalian species, but also significant differences. VIP is a cholinergic cotransmitter in the intrinsic innervation of the human gut. The substantial overlap between VMAT2 and TH in enteric neurons indicates that the intrinsic catecholaminergic innervation is a stable component of the human GI tract throughout life. The absence of DBH from intrinsic catecholaminergic neurons indicates that these neurons have a dopaminergic phenotype.

Acetylcholine↗
PubMed1980

Gastrointestinal metabolism and transport of pesticidal carbamates.

Published evidence pertaining to gastrointestinal absorption and metabolism of pesticidal carbamates will be reviewed. The major body of evidence will come form investigations conducted by the author on N-methylcarbamate pesticides with rats; few investigations directly involving the gastrointestinal system have been reported by other research groups. Results derived from in vitro and isolated in vivo preparations show that pesticidal carbamates are absorbed and metabolized by gastrointestinal tissues. Numerous gastrointestinal metabolites have been separated; some have been identified and their behavior in the gut characterized; these data will be included in the review to the extent they have been published. The absorptive and metabolic capacities of the gastrointestinal system vary from one region to another. The author draws from evidence obtained from in vitro and in vivo studies and proposes the events that occur between carbamate ingestion and the appearance of the compound and/or its metabolites in the portal blood or mesenteric lymph. In this endeavor, the author acknowledges that superimposition of the metabolic precursory substrate-product sequence on the sequential physiologic steps from ingestion to defecation produces a complex situation which is difficult if not impossible to study meaningfully by investigation of one tissue component at a time (i.e., epithelial uptake, epithelial metabolism, mucosal to serosal transport, etc.).

Animals↗
PubMed1994

Gastrointestinal hemorrhage complicating systemic neurofibromatosis.

A case of gastrointestinal hemorrhage caused by small bowel neurofibromas in a gentleman with systemic neurofibromatosis is presented. The multiple presentations of gastrointestinal system involvement by neurofibromatosis are reviewed. Early diagnosis and localization of small bowel tumors remains a dilemma. Mesenteric angiography and early surgical intervention are recommended.

Gastrointestinal Hemorrhage↗
PubMed2004

Gastrointestinal absorption of metallic mercury.

The absorption of mercury from the gastrointestinal systems of 7 subjects, of whom none had any amalgam fillings, was examined in this study. The authors obtained quantitative information about mercury concentration in plasma and duodenal fluid after the gastrointestinal systems of the subjects were exposed to liquid elemental mercury enclosed in rubber balloons (i.e., approximately 20 g of mercury), using a standard procedure followed for the sampling of bile. Plasma samples were collected prior to exposure, as well as up to 10 d following exposure, and duodenal fluid was collected 1 h, 2 h, 4 h, and 6 h during the intubation process. The authors studied the kinetics of dissolution in vitro by leaching elemental liquid mercury and mercuric chloride. The results of this study supported the hypothesis that metallic mercury is oxidized in the gastrointestinal tract. In addition, the authors determined that duodenal intubation, while using liquid metallic mercury in rubber bags, resulted in the diffusion of minor amounts of atomic elemental mercury through the rubber walls. The absorbed amount of mercury that reached the central circulation was comparable to a daily dose of mercury from dental amalgam in the amalgam-bearing population.

Absorption↗
PubMed1988

Monoclonal antibody assays for measuring ovarian tumor antigen in blood. Detection of NB/70K in patients with ovarian cancer and nongynecologic diseases.

Blood levels of human ovarian tumor antigen NB/70K were measured using four different monoclonal anti-NB/70K antibody radioimmunoassays (NB12123, NB12913, NB13834, and NB13831 assays). Four hundred thirty-two blood samples were obtained from apparently disease-free controls, from patients with benign and malignant ovarian tumors, and from patients with benign nontumorous and malignant diseases of the breast, lung, and gastrointestinal systems. The means, medians, and percent of samples that had elevated levels of NB/70K were calculated for each group of patients or controls for each assay. For all control versus malignant disease comparisons, there were statistically significant differences in all assays. For all benign versus malignant disease comparisons in the ovary, breast, lung, and gastrointestinal systems, there were statistically significant differences in all assays with the exception of the benign versus malignant gastrointestinal disease comparison in the NB12123 assay. Elevated NB/70K levels were detected in blood from ovarian cancer patients, almost all of whom had adenocarcinomas. Elevated NB/70K levels were also detected in blood samples from patients with adenocarcinoma, squamous, and clear cell carcinomas of the lung as well as in adenocarcinoma and ductal carcinoma of the breast. These results indicate that NB/70K is a marker for different pathologic types of malignancies.

Antibodies, Monoclonal↗
PubMed2002

[Massive lower gastrointestinal bleeding in the elderly].

BACKGROUND: This study was performed to evaluate the results of massive lower gastrointestinal bleeding in the elderly patients. METHODS: The data of patients older than 60 years with massive lower gastrointestinal bleeding were retrospectively analyzed between January 1999 and March 2002. RESULTS: There were 14 (52%) males and 13 (48%), females with mean age of 70.2 years (range 60 to 88). Twenty patients were diagnosed with colonoscopy. Angiography was employed in six, scintigraphy in three and r- enteroclysis in two patients. Colonic diverticulosis was the leading etiologic factor (48%). Mean comorbidity and hospital stay were 1.59 and 6.7 days, respectively. Conservative treatment were performed in eighteen, band JCC, ligation in three, surgery in five and embolization in two patients. Mortality rate was 26%. Mortality was high it in patients who had a lower initial diastolic pressure and required more transfusions (p:0.006 and p:0.025, respectively ) CONCLUSION: Massive lower gastrointestinal system bleeding in the elderly with comorbidities is associated with higher rate of mortality. Surgery in these patients has high mortality rates. Endoscopic and conservative diagnosis and treatment methods should be the first choice in the elderly. Key words: Bleeding, lower gastrointestinal system, elderly.

Aged↗
PubMed2003

Does the cholinergic system modulate gastrointestinal slow waves during less active phases of migrating myoelectric complex in healthy rams?

In six healthy rams possessing seven bipolar electrodes sewn onto the antrum and entire small intestine, the myoelectric activity recordings were performed in order to further elucidate the problem of possible contribution of cholinergic system in the control of slow wave amplitude and frequency. Experiments were carried out in fasted and non-fasted animals before and after feeding and intravenous cholinergic drug administration during phase 2b of the migrating myoelectric complex (MMC) (carbachol) and during phase 1-2a MMC (hexamethonium, atropine and pirenzepine). Antral slow wave amplitude was unaltered by cholinergic drugs with some exceptions. Small intestinal slow wave amplitude (principally examined in the jejunum) was also unchanged. Antral slow wave frequency was mostly unchanged with an increasing tendency but in some of experimental groups the results were statistically significant. Small intestinal slow wave frequency was diminished by carbachol and was partially increased (mostly increasing tendency) by the anticholinergic drugs. Thus, it is concluded that the cholinergic system can affect slow wave frequency in ovine antrum as well as in the small intestine in various phases of the MMC.

Acetylcholine↗