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)

Biliary stricture and duodenal obstruction have been increasingly recognized as complications of chronic pancreatitis. The anatomical relationship of the distal common bile duct and the duodenum with the head of the pancreas is the main factor for their involvement in chronic pancreatitis. In hospitalized patients with pancreatitis, the incidence of biliary stricture and duodenal obstruction is reported to be about 6% and 1.2%, respectively. For patients requiring an operation for chronic pancreatitis the incidence increases to 35% for biliary stricture and 12% for duodenal obstruction. Fibrosis around the distal common bile duct can cause stenosis with obstruction of bile flow. Clinically, the presentation of these patients ranges from being asymptomatic with elevated alkaline phosphatase or bilirubin, or both, to being septic with cholangitis. Jaundice, cholangitis, hyperbilirubinemia, and persistent elevation of serum alkaline phosphatase occur more frequently in patients with pancreatitis with a biliary stricture. A twofold elevation of alkaline phosphatase is a marker of possible common duct stenosis in patients with chronic pancreatitis. The incidence of both biliary cirrhosis and cholangitis in these patients is about 10%. ERCP reveals a characteristic long, smoothly tapered stricture of the intrapancreatic common bile duct. In duodenal obstruction, the factors that convert self-limiting edema to chronic fibrosis and stricture formation are unknown, but ischemia superimposed on inflammation may be the major cause. These patients present with a prolonged history of nausea and vomiting. Barium studies typically show a long constricting lesion of the duodenum, and endoscopy reveals reactive inflammatory changes in a narrowed duodenum. Operation is indicated in patients with common bile duct strictures secondary to chronic pancreatitis when there is evidence of cholangitis, biliary cirrhosis, common duct stones, progression of stricture, elevation of alkaline phophatase and/or bilirubin for over a month, and an inability to rule out cancer. The operation of choice is either choledochoduodenostomy or choledochojejunostomy. A cholecystoenterostomy is less favored because of its higher failure rate (23%). Endoscopic stenting plays a role in patients who are unfit for surgery, but it is not recommended as definitive therapy. For duodenal obstruction, failure to resolve the obstruction with 1-2 weeks of conservative therapy is an indication for bypass. The operation of choice is a gastrojejunostomy. Not uncommonly, combined obstruction of the pancreatic duct, common bile duct, and duodenum will develop. Combined drainage procedures or resection are used to manage these problems.
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PMID:Management of biliary and duodenal complications of chronic pancreatitis. 1453 24

The aim of this work was to investigate the role of the inward rectifying (K1) and the sarcolemmal ATP-sensitive K+ (K-ATP) channels in the electrical response to regional ischemia and the subsequent development of ventricular tachyarrhythmias on reflow (RA). Surface electrograms (ECG) and the transmembrane potential from subepicardial left ventricular cells were recorded in spontaneously beating rat hearts perfused with buffer alone (controls) or exposed to 100 microM BaCl2 or 100 microM 5-hydroxydecanoate (5-HD) to block either K1 or K-ATP channels respectively. After 20 min of equilibration and 10 min of control recordings, the left anterior descending coronary artery was occluded for 10 min. This was followed by reperfusion. The effects of regional ischemia as well as those of reperfusion (10 min) were recorded throughout. In the three groups, ischemia induced a modest decrease in heart rate and a sharp reduction in resting potential within 3 min. The latter as well as the accompanying depression of propagated electrical activity were enhanced by Ba2+. A partial recovery of the resting potential was observed in all groups during the last 2 min of coronary occlusion. Concomitantly, a slight reduction in the action potential duration was found in the control hearts. This effect was blocked by 5-HD. Under Barium the action potential duration increased by a factor of 3 and its ischemic variations were minimized. Severe sustained ventricular tachyarrhythmias developed on reflow in the controls and in the 5-HD exposed hearts. Barium limited the duration of arrhythmic episodes to a few seconds. Our data indicate that the initial electrical effects of ischemia are unrelated to activation of ATP sensitive K+ channels and that gK1 dominates the K+ membrane conductance at this stage. Furthermore, they show that action potential lengthening limits the duration of arrhythmic episodes triggered by reperfusion. This suggests that electrical heterogeneity plays an important role in the perpetuation of reperfusion arrhythmias.
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PMID:Effects of barium and 5-hydroxydecanoate on the electrophysiologic response to acute regional ischemia and reperfusion in rat hearts. 1467 97

Midgut malrotation is an anomaly of fetal intestinal rotation that usually presents in the first month of life. It is rare for malrotation to present in adulthood. Symptomatic patients present either acutely with bowel obstruction and intestinal ischemia with a midgut or cecal volvulus, or chronically with vague abdominal pain. Chronic symptoms can often make the diagnosis difficult. Findings diagnostic of malrotation are described using several modalities such as barium studies, computed tomography (CT) scans, angiography, and often emergent laparotomy. Treatment remains the Ladd procedure originally described by Dr. Ladd in 1936. Complete resolution of acute obstruction or chronic abdominal pain is the result of a high index of suspicion for malrotation, appropriate diagnostic studies, and aggressive definitive surgical treatment. We present a case of malrotation in an adult who presented with chronic abdominal pain. Midgut malrotation is a congenital anomaly referring to either lack of or incomplete rotation of the fetal intestines around the axis of the superior mesenteric artery during fetal development. Most patients present with bilious vomiting in the first month of life because of duodenal obstruction or a volvulus. It is rare for this condition to present in adulthood. The true incidence in adults is difficult to estimate because most patients who remain are asymptomatic and their conditions are, therefore, never diagnosed. A literature review by von Flue et al cites 40 cases from 1923 to 1992. Patients who are symptomatic often present either acutely with bowel obstruction and intestinal ischemia with a midgut or cecal volvulus or chronically with vague abdominal pain. These symptoms are caused by peritoneal bands first described by Ladd in 1932. These bands run from the cecum to the right lateral abdominal wall. We present a case of malrotation in an adult who presented with chronic abdominal pain.
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PMID:Adult malrotation: a case report and review of the literature. 1497 16

The aim of the study was analysing of the diagnostic value of different imaging modalities in evaluation patients with bowel obstruction. The material comprises a group of 47 patients with diagnosed acute abdomen. Erect radiography, and radiographs in supine and left lateral patients' positions, US and CT examination were performed in those patients. CT examination was performed in 5 mm--and 10-mm thick axial sections before and after administering the contrast agent. In 6 patients small barium enema was performed. In 5 cases water-soluble contrast was administered orally. In 6 cases on plane radiographs the presence of high small bowel obstruction was found. In 3 cases the level of small bowel obstruction was in the distal ileum. In 12 patients the obstruction of large bowel was seen on plain radiographs. In 3 patients intussusception of sigmoid bowel was found. The mesenteric ischemia was found to be a reason of bowel obstruction in 5 cases. On CT section soft tissue mass with irregular contrast enhancement was found, reflecting ischemic intestinal loops. In 2 patients the gall stone small bowel obstruction was found. In one of them the presence of gas in the biliary tree was seen on CT images. The determining of the level of the obstruction is facilitated on plain radiographs, erect and in supine and left lateral patients' position. In small bowel obstruction, normal or equivocal initial radiographs may result in a delayed diagnosis. As the bowel diameter cannot be assessed the plain radiographic diagnosis is difficult or impossible. If there is persistent diagnostic difficulty, follow-up plain radiographs taken a few hours later will often resolve the problem and, if not, a barium study or CT may be performed. Orally administering of water-soluble contrast agent, diluted barium, barium enema are also helpful in differentiating the character and etiology of obstruction.
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PMID:The diagnostic value of different imaging modalities in evaluation of bowel obstruction. 1614 91

Among the electrophysiological properties differentiating stratum oriens horizontal interneurons from pyramidal neurons of the CA1 hippocampal subfield are the more depolarized resting potential and the higher input resistance; additionally, these interneurons are also less sensitive to ischemic damage than pyramidal cells. A differential expression of pH-sensitive leakage potassium channels (TASK) could contribute to all of these differences. To test this hypothesis, we studied the expression and properties of TASK channels in the two cell types. Electrophysiological recordings from acute slices showed that barium- and bupivacaine-sensitive TASK currents were detectable in pyramidal cells but not in interneurons and that extracellular acidification caused a much stronger depolarization in pyramidal cells than in interneurons. This pyramidal cell depolarization was paralleled by an increase of the input resistance, suggesting the blockade of a background conductance. Single-cell reverse transcription-PCR experiments showed that the expression profile of TASK channels differ between the two cell types and suggested that these channels mediate an important share of the leakage current of pyramidal cells. We suggest that the different expression of TASK channels in these cell types contribute to their electrophysiological differences and may result in cell-specific sensitivity to extracellular acidification in conditions such as epilepsy and ischemia.
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PMID:Differential expression of TASK channels between horizontal interneurons and pyramidal cells of rat hippocampus. 1620 75

The most significant advances in the management of small-bowel obstruction are developments in imaging modalities available to assist in the diagnosis itself, as well as to possibly assist in the early identification of those cases requiring urgent operative decompression. The most marked of these have been in the use and interpretation of contrast-enhanced CT. This has decreased the use of barium studies and has largely supplanted ultrasound and magnetic resonance imaging in the management of these patients. Diagnostic and therapeutic laparoscopic techniques are also growing in both capability and popularity. Laparoscopic adhesiolysis and the adjuvant of bioresorbable membranes each hold promise but have yet to become established as standard treatment. Further progress is needed in the detection of early, reversible strangulation. As a consequence, the fundamentals of the surgical management of small-bowel obstruction have evolved little over the past 15 years. With our persistent inability to detect reversible ischemia, a substantial risk of progression to irreversible ischemia remains when surgery is delayed, particularly in the setting of suspected complete obstruction.
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PMID:Current management of small-bowel obstruction. 1625 May 44

1. We evaluated changes in contractility of the guinea-pig isolated ileum, using intact segments and myenteric plexus-longitudinal muscle (MPLM) preparations, after several times (5-160 min) of ischemia in situ. 2. Intestinal ischemia was produced by clamping the superior mesenteric artery. Ischemic and nonischemic segments, obtained from the same guinea-pig, were mounted in organ baths containing Krebs-bicarbonate (K-B) solution, maintained at 37 degrees C and gassed with 95% O2/5% CO2. The preparations were allowed to equilibrate for 60 min under continuous superfusion of warm K-B solution and then electrically stimulated at 40 V (0.3 Hz, 3.0 ms). Thereafter, complete noncumulative concentration-response curves were constructed for acetylcholine (ACh), histamine (HIS), potassium chloride (KCl), and barium chloride (BaCl2). Mean Emax (maximal response) values were calculated for each drug. 3. Our study shows that alterations of chemically and electrically evoked contractions are dependent on ischemic periods. It also demonstrates that contractile responses of ischemic tissues to neurogenic stimulation decreases earlier and to a significantly greater extent than the non-nerve mediated responses of the intestinal smooth muscle. Contractile responses to smooth muscle stimulants were all similarly affected by ischemia. Electron microscopy images indicated necrotic neuronal death. The decrease in reactivity of ischemic tissues to electrical stimulation was ameliorated by dexrazoxane, an antioxidant agent. 4. We consider the guinea-pig isolated ileum as a useful model system to study the processes involved in neuronal ischemia, and we propose that the reduction in maximal responses to electrical stimulation is a useful parameter to study neuroprotection.
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PMID:Altered responsiveness of the guinea-pig isolated ileum to smooth muscle stimulants and to electrical stimulation after in situ ischemia. 1634 Dec 32

Ever since its earliest reports, portal venous gas (PVG) has been associated with numerous intraabdominal catastrophes and has served as an indication for urgent surgical exploration. It is traditionally regarded to be an ominous finding of impending death, with highest mortality reported in patients with underlying bowel ischemia. Today, computed tomography has demonstrated a wider range of clinical conditions associated with PVG, some of which are "benign" and do not necessarily require surgery, unless when there are signs of intraabdominal catastrophe or systemic toxicity. One of these "benign" conditions is Crohn's disease. The present report describes a 19-year-old Chinese boy with Crohn's pancolitis who presented with septic shock associated with PVG and portal vein thrombosis, and was successfully managed surgically. To our knowledge, this is the first report of PVG and portal vein thrombosis associated with Crohn's disease in a Chinese patient. In addition, we have also reviewed the reports of another 18 Crohn's patients with PVG previously described in the English literature. Specific predisposing factors for PVG were identified in 8 patients, including barium enema, colonoscopy, blunt abdominal trauma, and enterovenous fistula. The patients who developed PVG following barium enema and blunt trauma were all asymptomatic and no specific treatment was necessary. Eleven patients (58%) who presented with signs of intraabdominal catastrophe or systemic toxicity required either immediate or eventual surgery. The overall mortality rate among the 19 patients was only 11%. The present literature review has shown that the finding of PVG associated with Crohn's disease does not always mandate surgical intervention. It is the clinical features and the related complications that ultimately determine the treatment approaches. The overall outcome of PVG associated with Crohn's disease has been favourable.
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PMID:Portal venous gas and thrombosis in a Chinese patient with fulminant Crohn's colitis: a case report with literature review. 1700 7

We report a case of inferior mesenteric arteriovenous fistula without portal hypertension or mesenteric ischemia. A 64-year-old man had developed frequent mucous diarrhea during the previous month. Colonoscopy showed highly edematous mucosa of the rectum. Barium enema demonstrated localized stricture of the same part but no evidence of malignancy. Finally we established a diagnosis by 3D-CT and selective abdominal angiography. Transcatheter arterial embolization was successfully performed. After that, his symptoms gradually improved as all abnormal findings on colonoscopy, barium enema and abdominal CT disappeared.
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PMID:[Transcatheter embolization of an inferior mesenteric arteriovenous fistula with frequent mucous diarrhea]. 1728 13

Gastric volvulus is defined as an abnormal rotation of all or part of the stomach around one of its axes. It is a diagnostic emergency and therapeutic challenge because in acute forms it may lead to gastric strangulation with a high risk of ischemia and necrosis. Organoaxial and mesentericoaxial volvulus are distinguished according to the direction of rotation. The most common cause of gastric volvulus is hiatal hernia, but the principal predisposing factor is ligamentous laxity. The diagnosis is suspected when erect chest radiograph images show a high air-fluid level in the chest. Moreover a barium swallow is essential to confirm the diagnosis. Nonetheless, a computed tomography (CT) scan now provides a comprehensive description of the thoracic lesion, including stomach vitality. Gastric volvulus requires surgical treatment, specifically volvulus reduction, reintegration of the stomach into the abdominal cavity in cases of intrathoracic migration, and correction of causal factors. Resection of the hernial sac and the role of gastropexy for preventing recurrence remain controversial. Advances in laparoscopic surgery have made possible a laparoscopic approach to most cases of chronic gastric volvulus.
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PMID:[Gastric volvulus: diagnosis and management]. 1758 36


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