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PubMed1999

Malignant lymphoma of the gastrointestinal tract.

AIMS: The gastrointestinal tract (GIT) is the most common site of extra-nodal lymphoma. Most of these lymphomas arise from mucosa associated lymphoid tissue (MALT). We attempt in this study to define the natural history and treatment outcome of this type of lymphoma. METHODS: We carried out a retrospective study of patients presenting at our centre with histopathological diagnosis of primary GIT lymphoma between 1990 and 1994. RESULTS: Equal numbers of cases of stomach and small bowel lymphoma were found. Vomiting and feeling of fullness were the two most common presenting symptoms. Large cell type and high grade tumours were found to be the commonest histological types. All the patients were treated with surgery followed by chemotherapy. A 5-year disease-free survival (DFS) rate of 73%) was observed with a confidence interval of 0.65-1.35. Survival in stomach cancer was 73.5% (95% CI 0.26-1.74) while it was 76.4% in small bowel tumours (95% CI 0.54-1.46). The difference in survival was not statistically significant. CONCLUSIONS: Although there is no consensus regarding treatment of primary GI lymphoma, surgery and adjuvant chemotherapy yield good survival.

Diagnosis, Differential↗
PubMed1994

CD34 expression by gastrointestinal tract stromal tumors.

Gastrointestinal stromal tumors (GISTs) are neoplasms arising in the wall of the gastrointestinal tract that frequently show evidence of smooth muscle differentiation, either by their appearance alone or by immunohistology. A significant number of these neoplasms fail to react with any markers of muscle differentiation, however. A subset of these neoplasms have epithelioid features, and the presence of these features can give rise to confusion with other neoplasms, such as carcinomas and melanomas. Here we show that the CD34 monoclonal antibody My10 reacts with 19 of 23 (83%) of these lesions, including both those with and without epithelioid features. Five of 10 epithelioid and one of 13 spindled neoplasms lacked detectable muscle-specific actin (MSA), smooth muscle actin (SMA), and desmin; all six were CD34 reactive. Immunoblotting experiments show that the antigen on these stromal neoplasms has a molecular weight identical to that found on hematopoietic cells. The frequency and intensity of the reactivity of GISTs with anti-CD34 antibodies are distinctly higher than those reported for smooth muscle neoplasms of soft tissue and myometrium. This reactivity can be a useful adjunct in the diagnosis of difficult cases, especially in those exhibiting epithelioid morphology.

Actins↗
PubMed2004

Reefs in experimental gastroenterology--cyclic activities of the gastrointestinal tract.

The activity of the upper gastrointestinal tract is periodic. It concerns the gastrointestinal and gallbladder motility, gastrointestinal blood flow, gastric, intestinal, pancreatic and biliary secretions, rate of nutrient absorption, and many other physiological events. Nowadays, the periodic activity of the gastrointestinal tract is considered as a basic physiological pattern in conscious animals and humans. Unfortunately, there are considerable species- and age-related as well as individual differences, therefore experimental protocols should consider first describing the individual periodic pattern in the examined animals. A lot of confusion may appear with data interpretation if the periodic activity is neglected, in particular when low physiological-like doses of test substances are used. For instance, the effect of CCK or VIP administration on the exocrine pancreas may differ from negligible effect to strong one depending of the phase of pancreatic secretion. The action of secretagogues on the gastrointestinal tract will also be discussed in terms of the ultradian and circadian cycles.

Animals↗
PubMed1999

Surgery for melanoma metastatic to the gastrointestinal tract.

BACKGROUND: Gastrointestinal (GI) metastasis from melanoma has a dismal prognosis with few long-term survivors. We evaluated the role of operative intervention for melanoma metastases to the GI tract and attempted to identify prognostic factors to improve selection of patients for surgery. METHODS: Between 1977 and 1997, 68 of the 7965 patients with melanoma admitted to Memorial Sloan-Kettering Cancer Center underwent surgical exploration for melanoma metastatic to the GI tract. Characteristics of the primary tumor, regional lymph nodes, and metastatic pattern were reviewed. Data concerning the presenting signs and symptoms, laboratory values, operative findings, extent of surgical resection, recurrence pattern, and survival were analyzed. RESULTS: The most common presenting clinical features included anemia (n = 41; 60%) or abdominal pain (n = 40; 59%). The most frequently involved portion of the GI tract was the small bowel (n = 62; 91%), and the most common operative procedure was small bowel resection (n = 54; 79%). Postoperative mortality and morbidity were 2.9% (n = 2) and 8.8% (n = 6), respectively. Presenting symptoms were relieved in 90% of patients (n = 61). Median survival for all 68 patients following operative intervention was 8.2 months, with 18% survival at 5 years. By multivariate analysis, complete resection rendering the patient free of all identifiable disease (n = 19, median survival 14.9 months, 38% survival at 5 years) and a low preoperative serum lactate dehydrogenase (LDH) (n = 28, median survival 13.6 months, 35% survival at 5 years) were identified as independent favorable prognostic factors for survival. CONCLUSIONS: Operative intervention for melanoma metastatic to the GI tract is recommended for palliative reasons and can be performed with low morbidity and mortality. It is associated with prolonged survival in patients rendered free of all identifiable disease following surgical resection and in those with a low preoperative serum LDH.

Abdominal Pain↗
PubMed1989

Immunoreactive atrial natriuretic peptide (ANP) in endoscopic biopsies of the human gastrointestinal tract.

The human gastrointestinal tract, important for body salt and water balance, was investigated by endoscopic biopsy for the presence of atrial natriuretic peptide (ANP). Using immunohistochemistry, ANP-immunoreactive cells were identified in the lamina epithelialis mucosae of stomach, duodenum, jejunum, colon, and rectum. The findings indicate that ANP plays a role in intestinal salt and water regulation in man. ANP measurements in tissue specimens reached by endoscopic biopsy may be of major interest for future investigations on (patho-)physiological and pharmacological aspects of ANP.

Adult↗
PubMed2002

Peripheral activity of a new NK1 receptor antagonist TAK-637 in the gastrointestinal tract.

Pathways controlling gastrointestinal function involve the activation of neurokinin NK1 receptors by substance P (SP) under normal and pathological conditions. Our aim was to pharmacologically characterize the effect of a nonpeptide NK1 receptor antagonist TAK-637 [(aR,9R)-7-[3,5-bis(trifluoromethyl)benzyl]-8,9,10,11-tetrahydro-9-methyl-5-(4-methylphenyl)-7H-[1,4]diazocino[2,1-g] [1,7]naphthyridine-6,13-dione] and determine key mechanisms of TAK-637 action in the gastrointestinal tract. Experiments were performed using intestinal preparations isolated from the guinea pig. The selective agonists of NK1 receptors, [Sar9,Met(O2)11]-SP and GR 73632 [H2N-(CH2)4-CO-Phe-Phe-Pro-NMe-Leu-Met-NH2], induced contractions in colonic longitudinal muscle pretreated with atropine. TAK-637 (1-100 nM) caused a rightward shift of the concentration-response curves showing nanomolar affinity against [Sar9,Met(O2)11]-SP (Kb = 4.7 nM) and GR 73632 (K(b) = 1.8 nM). This antagonist effect remained unchanged by tetrodotoxin. Furthermore, neither the contractions of colonic circular muscle induced by selective activation of NK2 receptors by GR 64349 (Lys-Asp-Ser-Phe-Val-Gly-R-gamma-lactam-Leu-Met-NH2) nor the responses of taenia coli induced by the selective NK3 receptor agonist senktide were affected by TAK-637 (100 nM). Studies of electrically induced neurogenic contractions showed that TAK-637 had no effect on cholinergic responses to single-pulse (0.5 ms) stimulation or stimulation with increasing frequency (1-16 Hz, 0.5 ms, 5-s train duration). In contrast, TAK-637 significantly reduced nonadrenergic, noncholinergic contractions of colonic longitudinal muscle evoked at frequencies of 8 to 16 Hz and prevented the development of capsaicin-induced contractions in isolated segments of terminal ileum. Our results indicate that TAK-637 is a selective antagonist of smooth muscle NK(1) receptors that activate intestinal muscle contraction. Additionally TAK-637 inhibits neuronal NK1 receptors involved in the "local" motor response to stimulation of capsaicin-sensitive primary afferents.

Animals↗
PubMed2005

Human defensin 5 expression in intestinal metaplasia of the upper gastrointestinal tract.

BACKGROUND: Upper gastrointestinal tract intestinal metaplasia (IM) is termed Barrett's oesophagus (BO) or gastric intestinal metaplasia (GIM), depending on its location. BO and GIM are associated with chemical exposure resulting from gastro-oesophageal reflux and chronic Helicobacter pylori infection, respectively. Paneth cells (PCs), characterised by cytoplasmic eosinophilic granules, are found in a subset of IM at these sites, but histology may not accurately detect them. AIM: To determine human defensin 5 (HD5; an antimicrobial peptide produced by PCs) expression in BO and GIM, and to investigate its association with H pylori infection. METHODS: Endoscopic biopsies from 33 patients with BO and 51 with GIM, and control tissues, were examined by routine histology and for H pylori infection and HD5 mRNA and protein expression. RESULTS: In normal tissues, HD5 expression was specific for PCs in the small intestine. Five patients with BE and 42 with GIM expressed HD5, but few HD5 expressing cells in IM had the characteristic histological features of PCs. Most HD5 positive specimens were H pylori infected and most HD5 negative specimens were not infected. CONCLUSIONS: HD5 immunohistochemistry was often positive in IM when PCs were absent by conventional histology. Thus, HD5 immunohistochemistry may be superior to histology for identifying metaplastic PCs and distinguishing GIM from BO. The higher frequency of HD5 expression in GIM than in BO is associated with a higher frequency of H pylori infection, suggesting that in IM PCs may form part of the mucosal antibacterial response.

Adult↗
PubMed2006

Interstitial cells of cajal as pacemakers in the gastrointestinal tract.

In the gastrointestinal tract, phasic contractions are caused by electrical activity termed slow waves. Slow waves are generated and actively propagated by interstitial cells of Cajal (ICC). The initiation of pacemaker activity in the ICC is caused by release of Ca2+ from inositol 1,4,5-trisphosphate (IP3) receptor-operated stores, uptake of Ca2+ into mitochondria, and the development of unitary currents. Summation of unitary currents causes depolarization and activation of a dihydropyridine-resistant Ca2+ conductance that entrains pacemaker activity in a network of ICC, resulting in the active propagation of slow waves. Slow wave frequency is regulated by a variety of physiological agonists and conditions, and shifts in pacemaker dominance can occur in response to both neural and nonneural inputs. Loss of ICC in many human motility disorders suggests exciting new hypotheses for the etiology of these disorders.

Animals↗
PubMed1996

Characterization of Prostaglandin G/H Synthase 1 and 2 in rat, dog, monkey, and human gastrointestinal tracts.

BACKGROUND & AIMS: In the gastrointestinal tract, prostaglandins are implicated as important mediators of normal physiological processes. Prostaglandin G/H synthase (PGHS) is the first enzyme leading to the formation of prostaglandins. Two forms exist: the constitutive PGHS-1 and the inducible PGHS-2 isoforms. The purpose of this study was to examine the expression of PGHS-1 and -2 in gastrointestinal tissues. METHODS: PGHS-1 and -2 expression and activity were examined in rat, dog, monkey, and human gastrointestinal tracts by immunoblot and biochemical assays. RESULTS: PGHS-1 but not PGHS-2 protein was identified in all gastrointestinal tissues. PGHS-1 protein varied throughout the gastrointestinal tracts; interspecies differences were also noted. Immunohistochemical studies showed PGHS-1 staining of rat endothelial cells in all gastrointestinal regions; PGHS-2-specific staining was noted in a subset of macrophages in 3 of 22 rats examined. Elevated activity was shown in tissues expressing greater concentrations of PGHS-1 protein. Indomethacin, a nonsteroidal anti-inflammatory drug that inhibits both isoforms, inhibited prostaglandin synthesis, whereas NS-398, a selective PGHS-2 inhibitor, showed little or no inhibition of prostaglandin synthesis in gastrointestinal tissues. CONCLUSIONS: These results indicate that prostaglandins produced in normal gastrointestinal tissue and required for normal physiological functioning are derived from the PGHS-1 isoform.

Amino Acid Sequence↗
PubMedDate not supplied

Effect of thermal injury and immunosuppression on the dissemination of Candida albicans from the mouse gastrointestinal tract.

Candida albicans dissemination through the gastrointestinal tract was examined in mice given a thermal injury, immunosuppressive therapy, or both. After gastrointestinal tract colonization with C. albicans, mice were initially subjected to a 20% total body surface area, full-thickness, dorsal scald burn. Only one mouse in the burned group (5%) had evidence of C. albicans in the liver at the time the mice were killed. No dissemination was observed in sham-burned animals. When mice were immunosuppressed with cyclophosphamide, an increased incidence of gastrointestinal tract dissemination was noted in burned (31%) and sham-burned (23%) mice; however, only 3 days after burn was there a significant difference in dissemination between burned and sham-burned mice (p less than 0.02). This corresponded to the day of severest neutropenia in response to cyclophosphamide treatment. The results of the study indicate that C. albicans can disseminate from the gastrointestinal tract in response to thermal injury, but a significant suppression of the immune response must occur for the event to be commonplace.

Animals↗
PubMed1985

Endoscopic laser treatment of vascular anomalies of the upper gastrointestinal tract.

Vascular anomalies of the gastrointestinal tract are an important source of both acute and chronic blood loss. They present difficult management problems as they are often multiple, involving more than one part of the gastrointestinal tract, and may give rise to bleeds of increasing frequency and severity over a period of many years. We present the results of endoscopic argon and Nd YAG laser treatment of 18 patients with documented recurrent, severe haemorrhage from vascular lesions of the upper gastrointestinal tract with follow up of up to five years. Four patients with hereditary haemorrhagic telangiectasia, five with single angiodysplasias and three with multiple angiodysplasias have had their transfusion requirements reduced to minimal levels after one or more courses of laser treatment. Two of these have required no blood for over two years despite previous total requirements of 52 and 129 units of blood. Four patients were submitted to surgery (two in whom the laser failed to control haemorrhage and two who did not have immediate access to laser therapy at the time of severe bleed). Two of these, however, bled again soon afterwards. Two patients are still undergoing courses of laser therapy although have already shown reductions in transfusion requirements. Both lasers were effective. The Nd YAG laser appears to produce better long term results as its greater penetration makes it possible to ablate the main areas of vascular ectasia in the submucosa, although it does have a slightly higher risk of causing haemorrhage in the first few days after treatment.

Adult↗
PubMed2004

Multiple lymphomatous polyposis of the gastrointestinal tract.

CONTEXT: Gastrointestinal multiple lymphomatous polyposis is a rare type of malignant lymphoma that has aggressive biological behavior, early systemic dissemination and poor prognosis. It is considered to be a manifestation of non-Hodgkin lymphoma and represents the gastrointestinal counterpart of mantle cell nodal lymphoma. OBJECTIVE: A case of gastrointestinal multiple lymphomatous polyposis is presented and the anatomopathological, clinical, diagnostic and treatment aspects of this unusual neoplasia are discussed. CASE REPORT: The patient was a 59-year-old white male with a complaint of asthenia, night sweating, alteration in intestinal habit and weight loss over the preceding two months. The physical examination showed pallid mucosa and a palpable mass in the epigastrium and mesogastrium. Endoscopy of the upper digestive tract showed the presence of gastric and duodenal polyps. An opaque enema showed multiple polypoid lesions, especially in the cecum. A rectal biopsy revealed infiltration of the mucosa and submucosa by diffuse lymphoma consisting of small cleaved cells. Immunohistochemical study showed lymphocytes that expressed the antibody CD20 (L-26) and light-chain kappa (k) immunoglobulin, but not light-chain lambda (l) immunoglobulin. The patient presented a condition of acute intestinal obstruction with the presence of a mesenteric mass formed by agglutinated lymph nodes that surrounded the proximal ileum, thereby obstructing its lumen. He was submitted to a segmental enterectomy and gastrotomy with excisional biopsies of the gastric polypoid lesions. After two cycles of chemotherapy there was a worsening of the general state, with an increase in the dimensions of the abdominal masses and sepsis, accompanied by progressive respiratory insufficiency, leading to death.

Diagnosis, Differential↗
PubMed1995

Late effects of radiation therapy on the gastrointestinal tract.

Late gastrointestinal complications of radiation therapy have been recognized but not extensively studied. In this paper, the late effects of radiation on three gastrointestinal sites, the esophagus, the stomach, and the bowel, are described. Esophageal dysmotility and benign stricture following esophageal irradiation are predominantly a result of damage to the esophageal wall, although mucosal ulcerations also may persist following high-dose radiation. The major late morbidity following gastric irradiation is gastric ulceration caused by mucosal destruction. Late radiation injury to the bowel, which may result in bleeding, frequency, fistula formation, and, particularly in small bowel, obstruction, is caused by damage to the entire thickness of the bowel wall, and predisposing factors have been identified. For each site a description of the pathogenesis, clinical findings, and present management is offered. Simple and reproducible endpoint scales for late toxicity measurement were developed and are presented for each of the three gastrointestinal organs. Factors important in analyzing late complications and future considerations in evaluation and management of radiation-related gastrointestinal injury are discussed.

Dose-Response Relationship, Radiation↗
PubMed2004

Optical coherence tomography in the gastrointestinal tract.

Conventional gastrointestinal endoscopic instruments have provided ready access to the mucosal surface of the esophagus, stomach,small intestinal, colon, bile duct, and pancreatic duct. The evolution of endoscopic ultrasonography has provided an additional dimension to the clinical application of modern endoscopy and imaging technology.

Endoscopy, Gastrointestinal↗
PubMed1995

Familial adenomatous polyposis: should patients undergo surveillance of the upper gastrointestinal tract?

Upper gastrointestinal (UGI) endoscopy was performed in 35 asymptomatic patients with familial adenomatous polyposis (FAP) to assess the prevalence of gastric and duodenal polyps and to demonstrate efficacy of endoscopic surveillance in patients with FAP. UGI polyps were found in 25 (71%) of 35 polyposis patients. Among these, gastric fundic gland polyps were involved in seven patients, and UGI adenomas in 18 patients; there were nine gastric adenomas and 14 duodenal adenomas, including six cases of duodenal cancer. UGI polyps were found in 13 of 15 patients with extracolonic manifestations (87%), but in only 12 of 20 patients (60%) without. The median follow-up interval was 8.7 years in growing duodenal adenomas, but 3.5 years in adenomas without changes in size and number. It was concluded that surveillance gastroduodenoscopy every 3-5 years might be enough to treat duodenal adenomas by endoscopic mucosal resection.

Adenomatous Polyposis Coli↗
PubMed1980

Primary lymphoma of the gastrointestinal tract.

Primary gastrointestinal lymphoma represents approximately 1% of all gastrointestinal neoplasms. Gastric involvement is more common than small or large intestine and carries a better prognosis. Abdominal pain and weight loss may be the only manifestations and may be present for months or years before the diagnosis is made. Perforation and obstruction occur infrequently. Multiple tumors constitute 8% of cases. Although barium studies and endoscopy reveal the lesion in a high percentage of cases, exploratory celiotomy is not infrequently required for diagnosis. Only one-third of lymphomas are confined to the bowel at laparotomy. Histologically one-third are reticulum cell sarcomas and the remainder lymphosarcoma or lymphocytic lymphoma. Five year survival overall was 38%. Curative resections yielded a survival of 60% regardless of site while palliative resections offered only a 17% chance of cure. As expected, survival was inversely proportional to extent of nodal spread. Postoperative radiotherapy is recommended for residual disease.

Adolescent↗
PubMed1991

Topography of efferent vagal innervation of the rat gastrointestinal tract.

The gastrointestinal territories innervated by the gastric, celiac, and hepatic abdominal vagi were identified in rats with selective branch vagotomies by means of 1) anterograde tracing with the carbocyanine dye DiI injected into the dorsal motor nucleus and 2) measurement of cervical vagal stimulation-induced motility responses throughout the gut axis. Presence of DiI-labeled vagal terminals in the myenteric plexus and evoked motility responses were well correlated across the sampled gastrointestinal (GI) sites. In animals with only the two gastric branches intact, the entire stomach and the most proximal duodenum showed significant motility responses and were densely innervated, having DiI-labeled vagal terminals in almost every ganglion. The hepatic branch was found to primarily innervate the duodenum, with minor projections to the distal antral stomach and the intestines. The two celiac branches were found to almost exclusively innervate the jejunum, ileum, cecum and entire colon, and, together with the other vagal branches, the duodenum. Therefore, while there is some degree of specific innervation by the abdominal vagal branches of the oral-to-anal gut axis, which could be called "viscerotopic," the considerably overlapping innervation of the duodenum does not satisfy a viscerotopy criterion and needs further functional analysis.

Animals↗