Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0022116 (ischemia)
 91,303 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Leukocyte activation, adhesion, and emigration serve a protective role during a well-contained inflammatory response. However, under certain pathologic conditions such as endotoxemia, inflammatory bowel disease, and ischemia-reperfusion injury, leukocytes may turn against the host and aggravate--rather than prevent--tissue damage. Numerous experimental studies have been performed during the last decade to investigate the pathophysiologic role of leukocyte accumulation and adhesion during ischemia/reperfusion injury of various organs, in particular of the myocardium. Most of the latter studies investigated whether the consequences of experimental myocardial infarction could be attenuated by interventions aimed at the inhibition of chemotactic leukocyte infiltration or adhesion (or both) to microvascular endothelial cells. Although many promising results were reported, the consequent step towards an introduction of these strategies into experimental or even routine clinical management of patients with myocardial infarction has so far not been undertaken. In this manuscript, the authors try to give an overview on the state of the art of "antileukocyte" strategies in myocardial ischemia-reperfusion injury and to offer explanations for incongruent data obtained with diverse experimental approaches (animal species, treatment modalities, surgical and anesthesiologic artifacts, techniques for morphologic and functional evaluation of tissue damage). The authors conclude that long-term preclinical studies on suitable animal models, thoroughly investigating the positive and negative effects of antileukocyte interventions on the functional consequences of myocardial ischemia-reperfusion injury, are mandatory before the first clinical trial can be advocated.
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PMID:Impact of leukocyte adhesion on myocardial ischemia/reperfusion injury: conceivable mechanisms and proven facts. 845 35

The 21-aminosteroid tirilazad mesylate (U74006F) is a lipophilic antioxidant and free radical scavenger that has been reported to attenuate brain or spinal cord injury caused by trauma, stroke, ischemia and reperfusion injury. In this study, we have examined the effect of U74006F in reducing the inflammatory parameters of trinitrobenzene sulfonic acid (TNBS)-induced inflammatory bowel disease (IBD) in rats. To induce IBD, rats were given ethanolic TNBS intracolonically. Rats received either 1) TNBS and U74006F 2) TNBS and vehicle or 3) saline and vehicle. Rats were sacrificed 1, 2 and 3 weeks after IBD induction. Colon to body weight ratio (an index of tissue edema) was markedly increased in the vehicle-treated IBD rats after 1 week of administration of TNBS. The ratio was significantly lower after U74006F treatment and the trend remained even after 3 weeks of chronic inflammation. Myeloperoxidase (MPO) activity in vehicle-treated IBD rats was substantially increased compared with controls during the entire 3 weeks of the experiment. U74006F-treated animals had significantly reduced MPO activity (60% lower) when compared with vehicle-treated animals at the end of the second and third weeks. These observations were confirmed by histopathology studies showing reduced granulocyte infiltration after drug treatment. U74006F treatment decreased basal (by 70%) and fMLP stimulated (by 75%) superoxide generation from colonic tissue from IBD rats compared with vehicle treatment after 2 weeks, but there was no apparent difference in superoxide generation among all three groups after 3 weeks. The results of this study suggested that administration of U74006F effectively reduces the inflammatory parameters in this chronic rat model of IBD. As such, U74006F may be therapeutically beneficial for the treatment of IBD in humans.
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PMID:The 21-aminosteroid tirilazad mesylate can ameliorate inflammatory bowel disease in rats. 855 41

Obstructive colitis is an ulcero-inflammatory and necrotizing condition that occurs in the colon proximal to benign or malignant stenosing lesions. it is the result of ischemia due to impairment of blood supply secondary to elevation of the endoluminal pressure, distension of the colonic wall and other factors which impair adequate perfusion. The incidence among patients with colonic obstruction is reported at between 1 and 7%. Of 50 patients with this condition in this series, 30 female and 20 male, 2/3rds were well over 70 yrs of age. Obstruction was most common in the rectosigmoid. In half the patients this was due to adenocarcinoma, 24 were due to benign obstruction and 15 were caused by diverticular disease. Type, extent and depth of ischemic lesions were highly variable and comprised early mucosal hemorrhage and edema, ulcero-hemorrhagic lesions and transmural necrosis. There was always an abrupt transition between affected and normal bowel. A segment of preserved mucosa was usually present on the proximal side of the stenosis. In 16 patients massive dilatation with stretching and thinning of the bowel wall, associated with a blow-out type of perforation or with transmural necrosis, was observed and was considered to have resulted from a rapid rise of endoluminal pressure to high levels. The microscopic and macroscopic features are described in detail and histological factors discussed in relation to the pathological lesions encountered. Emphasis is placed upon the range of appearances and similarities are shared with other inflammatory colonic diseases, particularly idiopathic inflammatory bowel disease. The importance of recognition of this disease entity, not only by pathologists but by surgeons dealing with the disease at operation, is stressed.
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PMID:Obstructive colitis: an analysis of 50 cases and a review of the literature. 877 Nov 49

Idiopathic myointimal hyperplasia of the mesenteric veins (IMHMV) is a rare cause of intestinal ischemia secondary to venous compromise. A patient with this condition who presented with crampy abdominal pain, diarrhea, and rectal bleeding initially attributed to inflammatory bowel disease had several colonoscopies and ultimately a sigmoid colectomy. The colonic mucosa in biopsies performed at initial presentation and subsequently and in the resection specimen contained numerous hyperplastic, thick-walled, hyalinized vessels in the lamina propria, which have not been described in this entity previously. Examination of the mucosa in 27 resection specimens of ischemic enterocolitis of various etiologies, in five resections of prolapsed rectum, and in seven colostomy specimens revealed no instance in which there were similar histologic abnormalities. When seen on biopsy, therefore, these features should lead to inclusion of IMHMV in the differential diagnosis. Furthermore, the characteristic lesions of the submucosal and extramural veins in IMHMV were compared with those of 14 examples, from several organs, of veins subjected to arterial pressure and 21 cases of venous hypertension. The marked similarity of the arterialized veins to the mural veins of IMHMV suggests a role for arteriovenous fistulization in the pathogenesis of IMHMV, and a mechanism by which this might occur is proposed.
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PMID:Mucosal biopsy findings and venous abnormalities in idiopathic myointimal hyperplasia of the mesenteric veins. 882 35

180 ileoanal pouches constructed over 10 years and followed for at least 2 years (154 for Inflammatory Bowel Disease (IBD) and 26 for Familial Adenomatous Polyposis (FAP)) were reviewed. 23 pouches have been excised to date, 8 remain defunctioned (pouch failure FAP 7.7%, IBD 18.8%). The reasons for excision were: ischemia (n = 6), pelvic sepsis (n = 5), severe stenosis (n = 3), underlying Crohn's disease (n = 3), poor function (n = 5) and fistula (n = 1). The reasons for defunction were: Crohn's disease (n = 1), pelvic sepsis (n = 5) and ileoanal stenosis (n = 2). The projected overall pouch survival rate (Life table analysis) at 5 years was 81% (confidence interval 74-87%). Beyond 7 years, the figures to calculate survival became unreliable (small numbers). There was a significant association between pouch failure and pelvic sepsis (Fisher's exact test P < 0.0001) and between failure and fistula formation (P < 0.02). Multiple regression analysis showed pelvic sepsis and recurrent pouchitis to be independent factors of pouch failure. Pouch failure can occur many years after initial operation. Long-term follow up is recommended.
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PMID:Causes of failure and life expectancy of the ileoanal pouch. 911 42

Focal crypt injury by neutrophils (cryptitis/crypt abscesses), or focal active colitis (FAC), is a common isolated finding in endoscopic colorectal biopsies. Focal active colitis is often thought of as a feature of Crohn's disease, but may also be seen in ischemia, infections, partially treated ulcerative colitis, and as an isolated finding in patients undergoing endoscopy to exclude neoplasia. Clinical, endoscopic, and pathological data were retrospectively reviewed from 49 patients with focal active colitis, who had no other diagnostic findings on colorectal biopsy and no history of chronic inflammatory bowel disease. The histological findings were correlated with clinical diagnoses. Follow-up information was available for 42 of 49 focal active colitis patients. None developed inflammatory bowel disease; however, 19 patients had an acute self-limited colitis-like diarrheal illness, 11 had incidental focal active colitis (patients without diarrhea that were endoscoped to exclude colonic neoplasia and found to have asymptomatic FAC), 6 had irritable bowel syndrome, 4 had antibiotic-associated colitis, and 2 had ischemic colitis. Twenty patients were immunosuppressed, and 19 were taking nonsteroidal anti-inflammatory drugs. No histological features predicted final diagnoses. FAC did not predict the development of chronic colitis, even when mild crypt distortion or slight basal plasmacytosis was present. The preponderance of acute self-limited colitis and antibiotic-associated colitis among the FAC patients, along with the high number of immunosuppressed patients, support the conclusion that most FAC cases are infectious. The incidental detection of FAC in patients undergoing endoscopy to exclude colonic neoplasia was not clinically significant. The role of nonsteroidal anti-inflammatory drugs in FAC deserves further study.
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PMID:The clinical significance of focal active colitis. 971 35

The following article contains a short review on gastrointestinal problems of the elderly. The diseases of the esophagus occurring in the elderly are not much different from those in younger patients. Clinically relevant in the stomach are above all bleeding ulcerations and the gastric carcinoma occurring more frequently in advanced age. The pyogenic liver abscess is diagnosed primarily in the elderly and is at a rule the consequence of an infection of the gall bladder and other abdominal sites. The hepatocellular carcinoma does not grow rapidly in the elderly, but its accompanying unfavourable survival rate at five years is also approximately 5 per cent. In the case of symptomatic cholelithiasis, older high risk patients do especially profit from minimally invasive laparoscopic surgical procedures. Today, bile duct calculi are preferably treated by endoscopic papillotomy and following extraction of the calculi. The pancreas is subjected to atrophy, lipomatosis and fibrosis at the advanced age. However, these changes are rarely of clinical relevance. A frequent problem in clinical practice is that of constipation, from which 35% of patients suffer above the age of 65 years. Another typical symptom of the elderly is the incontinence, the different causes are being discussed. In advanced age, gastrointestinal hemorrhages are mostly occurring above the Treitz's ligament. Hemorrhages of the lower gastrointestinal tract occur mostly in the form of diverticle bleedings and those of angiodysplasias in the elderly. The diverticulosis is also a disease observed in over 50 per cent of patients above 70 years, but it is symptomatic in only part of the patients. When suspecting an inflammatory bowel disease in the elderly, the possibility of a mesenterial ischemia must always be considered as differential diagnosis. The classical chronic inflammatory bowel diseases can, however, also occur at advanced age. The colon carcinoma is one of the most frequent lethal causes in the Western countries 90 per cent of the cases of colon carcinoma are found in patients older than 50 years of age. Intensive attention is therefore required in this age group.
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PMID:[Gastrointestinal problems in elderly patients]. 933 52

Leukocyte-endothelial cell adhesion is now recognized to represent an early and rate-limiting step in the leukocyte infiltration and accompanying tissue injury that is associated with acute and chronic inflammatory diseases of the gastrointestinal tract. Adhesive interactions such as leukocyte rolling, adherence, and transendothelial migration are influenced by a variety of physical, chemical, and molecular factors that ultimately result in a net up-regulation or down-regulation of the inflammatory response. Coordination of this process is made possible by the mediator-specific, time-sensitive expression of adhesion glycoproteins on the surface of leukocytes and/or vascular endothelial cells. In this review, the different families of relevant adhesion molecules that participate in the coordinated recruitment of leukocytes into inflamed tissue are described and then discussed in terms of the pathophysiological alterations observed in selected experimental models of gastrointestinal disease. These include ischemia/reperfusion injury, radiation enteritis, inflammatory bowel disease, and the inflammatory responses to substances liberated by Helicobacter pylori and Clostridium difficile.
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PMID:Leukocyte-endothelial cell interactions: molecular mechanisms and implications in gastrointestinal disease. 955 98

Oxidative injury caused by free radicals is an important cause of tissue injury now recognized to occur in inflammation, ischemia and by the action of xenobiotics. It is also recognized to induce gene mutation and promote carcinogenesis. In this review the general concept of nett free radical injury counterbalanced by antioxidants is discussed as oxidative stress. The role of oxidative stress in intestinal ischemia, radiation enteritis, inflammatory bowel disease and the promotion of gastric and colorectal cancer is discussed. The data for the role of oxidative stress in the pathogenesis of ischemic, inflammatory and radiation induced disease are strong, but interventional studies with antioxidants have shown only weak beneficial effects in the above diseases. Therefore the role of antioxidants in the therapy of gastrointestinal diseases remains controversial and should be the subject of controlled trials.
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PMID:Oxidative stress and antioxidants in intestinal disease. 961 34

The antiinflammatory effects of alpha-melanocyte-stimulating hormone (alpha-MSH) molecules, specifically alpha-MSH(1-13) and its COOH-terminal tripeptide alpha-MSH(11-13), are well established. The peptides have been effective in tests of all major models of inflammation, and more recent tests have been extended to include experimental inflammatory bowel disease, CNS ischemia/reperfusion injury, and bacterial endotoxin-induced inflammation within the brain. The broad effectiveness of alpha-MSH molecules in all major types of inflammation indicates that the peptides exert actions that are very basic to the inflammatory process. Three general mechanisms of antiinflammatory action of alpha-MSH molecules have been identified: inhibition of production of inflammatory mediators by, or inhibition of inflammatory actions of, peripheral host cells; inhibition of peripheral inflammation induced by actions on melanocortin receptors within the brain; inhibition of CNS inflammation by local action of the peptides. It appears that alpha-MSH molecules have multiple actions that modulate the primitive inflammatory response.
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PMID:Mechanisms of antiinflammatory action of the neuroimmunomodulatory peptide alpha-MSH. 962 64


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