Based on the concept that ischemia is an important factor in the pathogenesis of acute pancreatitis, we developed a new model of complete ischemia/reperfusion of the pancreas in the rat. The aim of this study was to investigate the microcirculation of the pancreas after complete and reversible ischemia at different times after reperfusion by using intravital fluorescence microscopy. In addition, the effect of ischemia/reperfusion on the pancreas was assessed by means of light and electron microscopy and measurement of serum pancreas amylase concentration. In 35 adult Sprague-Dawley rats ischemia of the pancreas was induced by temporary occlusion of the four supplying arteries. Sham-operated animals served as controls (group A). After periods of 30 min (group B), 60 min (group C) or 120 min (group D) of ischemia the organ was reperfused. To exclude the influence of hypovolemia on microcirculation in group E (120 min ischemia) hydroxyethylstarch (HES) was given i.v. to maintain central venous pressure at baseline values. For intravital fluorescence microscopy the pancreas was exteriorized on a stage and quantitative analysis of microcirculation, including functional capillary density and leukocyte-endothelium interaction, was performed after 30 min, 1 h and 2 h of reperfusion. Serum pancreas-amylase was measured at control (prior ischemia) and at 2 h after reperfusion. Tissue samples for light and electron microscopy were taken 2 h after reperfusion. In sham-operated animals, functional capillary density (FCD) remained within baseline values (FCD 407.7 +/- 9 cm-1) during reperfusion. Dependent on the time of ischemia and time of reperfusion a gradual reduction in functional capillary density was observed; after 2 h of ischemia only 35% of capillaries were perfused (FCD 140.9 +/- 28.3 cm-1). Reduced functional capillary density was associated with an increase of perfusion heterogeneity to a maximum of 0.65 +/- 0.12, as against 0.13 +/- 0.02 in control animals. With a 2 h ischemia leukocyte-endothelium interaction was enhanced after 0.5 h of reperfusion (8-fold increase of adherent leukocytes in comparison to control) followed by a further significant increase until 2 h after the beginning of reperfusion. Amylase concentration after ischemia of 2 h (2967 +/- 289 U/l) was significantly higher as compared to controls (1857 +/- 99 U/l). Differences between group E and D were not observed. Pancreatic tissue injury was ascertained by histopathological studies. These results indicate that complete ischemia/reperfusion of the pancreas induces pancreatic microvascular failure. The severity of changes depends on duration of ischemia and duration of reperfusion. The morphological and biochemical changes suggest that ischemia/reperfusion causes an inflammatory reaction as observed in acute pancreatitis.

A small-colony variant (SCV) of Staphylococcus aureus was cultured from a patient with a persistent wound infection (abscess and fistula) 13 months after herniotomy. The strain was nonhemolytic, nonpigmented and grew only anaerobically on Schaedler agar. As it was coagulase-negative, it was initially misidentified as a coagulase-negative Staphylococcus. In further analysis, however, the microorganism was shown to be an auxotroph that reverted to normal growth and morphology in the presence of menadione and hemin (Schaedler agar) and could be identified as a SCV of Staphylococcus aureus. Surgery and antibiotic treatment of the patient with flucloxacillin and rifampicin for 4 weeks resulted in healing of the chronic wound infection.

DL offers an important diagnostic tool in excluding peritoneal penetration in ASW, hence lowering the rate of unnecessary laparotomies. Given experience and skills, laparoscopy may be used therapeutically in selected cases of ASW.

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The object of this investigation was to compare the effects of volatile anesthetics and of hemorrhage at comparable arterial blood pressures on splanchnic blood flow (radioactive microspheres) and tissue oxygenation of the liver and pancreas (surface PO2 [PSO2] electrodes). In contrast to earlier studies, we did not use identical minimum alveolar anesthetic concentration multiples as a reference to compare volatile anesthetics; rather, we used the splanchnic perfusion pressure. Under general anesthesia (intravenous chloralose) and controlled ventilation, 12 Sprague-Dawley rats underwent laparotomy to allow access to abdominal organs. Mean arterial pressure was decreased from 84 +/- 3 mm Hg (mean +/- SEM) at control to 50 mm Hg by 1.0 +/- 0.1 vol% halothane, 2.2 +/- 0.2 vol% enflurane, and 2.3 +/- 0.1 vol% isoflurane in a randomized sequence. For hemorrhagic hypotension, blood was withdrawn gradually until a mean arterial pressure of 50 mm Hg was attained. Volatile anesthetics and hemorrhage reduced cardiac output, and hepatic arterial, portal venous, and total hepatic blood flows by comparable degrees. Mean hepatic PSO2 decreased significantly from 30.7 +/- 2.6 mm Hg at control to 17.4 +/- 2 and 17.5 +/- 2 mm Hg during enflurane and isoflurane (each P less than 0.05) anesthesia, respectively. The decrease to 11.5 +/- 2.5 mm Hg was more pronounced during halothane anesthesia. Hemorrhagic hypotension was associated with the lowest hepatic PSO2 (3.4 +/- 1.3 mm Hg) and the highest number of hypoxic (0-5 mm Hg 86%) and anoxic PSO2 values (0 mm Hg 46%). Pancreatic blood flow and oxygenation remained unchanged from control during halothane and enflurane administration, whereas isoflurane increased both variables. Hemorrhagic hypotension slightly reduced pancreatic flow (-8%) but significantly decreased PSO2 from 58 +/- 5 mm Hg at control to 36 +/- 3 mm Hg, with 7% of all measured values in the hypoxic range. Thus, volatile anesthetics preserved pancreatic but not hepatic blood flow and tissue oxygenation in this rat model. Despite comparable effects on perfusion, the PSO2 of the liver and pancreas was the least during hemorrhagic hypotension compared to that with the anesthetics. Because the volative anesthetic-induced hypotension has such a different effect on splanchnic tissue oxygenation compared with hemorrhagic-induced hypotension, the authors conclude that the method of inducing hypotension may have different effects on oxygenation of various tissues.

Vascular mechanisms are not standard tools to induce acute pancreatitis. They are used for special purposes to investigate the pathophysiologic significance of circulatory changes in acute pancreatitis. Because of the rich collateral network, occlusion of the main pancreatic arteries induces no pathological change. Complete occlusion of the venous outflow induces hemorrhagic necrosis of the pancreas, disturbances of the microcirculation, edema and focal parenchymal necrosis as in acute pancreatitis. In the last model, pancreatic and systemic alterations can be examined.

We examined the influence of electrophoretic conditions on the detectability of small sequence alterations in DNA fragments by single strand conformation polymorphism (SSCP) analysis. Three acrylamide concentrations, 7.5, 14 and 20%, were selected, and all three gel types were prepared with four different Tris/borate/EDTA buffer concentrations. In addition, all these twelve gels were prepared both with and without 10% glycerol. All electrophoretic runs were performed at ambient temperature of 20-24 °C. The resulting 24 different electrophoretic conditions were used for the SSCP analysis of DNA fragments of exons 5, 7 and 8 of the human p53 gene; the results were evaluated primarily in relation to detectability of mutants. Six out of the 24 conditions permitted the detection of all mutants. For practical reasons, 14% acrylamide, 44.5 mmol/1 Tris, 44.5 mmol/1 boric acid, 1 mmol/1 EDTA, pH 8.0, with and without addition of glycerol was chosen as the most suitable. These "selected conditions" were applied in the SSCP analysis of an arbitrarily chosen set of mutant DNA fragments with single base exchanges, and all but one of seven mutants were detected in the gel system containing glycerol.Our results indicate that the set of "selected conditions" is of broad applicability, permitting the detection of even small sequence differences like single base exchanges with high reliability. It should prove especially useful in screening for unknown mutations.