Increased intrapancreatic trypsinogen activation in ischemia-induced experimental pancreatitis.

OBJECTIVE: The potential of pancreatic ischemia to cause acute pancreatitis as indicated by morphologic changes and ectopic trypsinogen activation was investigated. BACKGROUND: Experimental evidence has shown that pancreatic ischemia is important in the evolution of severe pancreatitis, but whether ischemia can initiate pancreatitis has been disputed. METHODS: Pancreatic ischemia was induced in rats by hemorrhagic hypotension (30 mm Hg for 30 min; n = 64). Changes of pancreatic microcirculatory perfusion were studied using diffuse reflectance spectroscopy. Serum amylase, trypsinogen activation peptide (TAP) in serum and pancreatic tissue, wet/dry weight ratio, and histology were determined over 24 hours and compared with sham-operated control subjects (n = 35). RESULTS: In control animals, serum amylase (47.9 +/- 2.1 units/L), serum (7.9 +/- 0.7 nmol/L) and tissue TAP (63.0 +/- 5.4 nmol/L x g), wet/dry weight ratio (2.8 +/- 0.1), and histology remained unchanged. Temporary hypotension markedly decreased pancreatic perfusion with incomplete recovery after reperfusion. Pancreatic isoamylase activity increased within 1 hour (110 +/- 5 units/L, p < 0.05) and further to 151 +/- 18 units/L at 24 hours. Tissue TAP was elevated at 1 hour (134 +/- 16 nmol/L x g, p < 0.05) and increased to 341 +/- 43 nmol/L x g (p < 0.001) after 24 hours, whereas serum TAP remained unchanged (8.3 +/- 0.5 nmol/L). Morphologic alterations included elevated wet/dry weight ratio (4.1 +/- 0.3, p < 0.01) and increased histologic scores for edema (p < 0.05) and acinar necrosis (p < 0.05) at 24 hours. Trypsinogen activation preceded the development of pancreatic necrosis. CONCLUSIONS: In addition to its potentiating role, severe pancreatic ischemia can play a pathogenetic role in the initiation of acute pancreatitis.

Failure of pentoxifylline to ameliorate severe acute pancreatitis in the rat: results of a prospective, randomized, controlled study.

OBJECTIVE: To investigate the benefit of pentoxifylline in severe experimental pancreatitis. DESIGN: Prospective, randomized, controlled study. SETTING: Experimental animal laboratory in a University hospital. SUBJECTS: Forty-two adult male Sprague-Dawley rats. INTERVENTIONS: Acute pancreatitis was induced by supramaximal stimulation with cerulein plus a pressure and volume controlled 10 min intraductal infusion of 10-mM glycodeoxycholic acid. Thirty minutes after pancreatitis was induced, animals were randomized to receive pentoxifylline (60 mg/kg over 2.5 hrs), or saline. All animals received fluid resuscitation with lactated Ringer's solution (8 mL/kg/hr), and surviving animals were killed at 24 hrs. MEASUREMENTS AND MAIN RESULTS: There was a progressively significant decrease in mean arterial pressure after pancreatitis was induced, with no difference between pentoxifylline-treated rats and controls. Hematocrit increased significantly in both groups at 6 hrs, and returned to baseline values at 24 hrs. Ascites volume and levels of trypsinogen activation peptide in plasma and ascites were similar in both groups. Twenty-four hour mortality was 47% for the pentoxifylline group and 52% for the control group. Histologic scores for necrosis, edema, inflammation, and hemorrhage showed no significant differences between the two groups. CONCLUSION: Treatment with pentoxifylline failed to improve outcome in a model of severe acute pancreatitis in the rat.

Intravenous contrast medium impairs oxygenation of the pancreas in acute necrotizing pancreatitis in the rat.

OBJECTIVE: Contrast-enhanced computed tomography is widely used to evaluate severe acute necrotizing pancreatitis (ANP) by demonstrating areas of malperfusion, which might indicate irreversible necrosis. Because of our prior finding that the intravenous contrast medium (CM) accentuates the severity of ANP by promoting further necrosis and higher mortality, we sought to investigate the mechanism by which this injury is mediated. DESIGN: Mild acute pancreatitis was induced in Sprague-Dawley rats with intravenous caerulein hyperstimulation; and severe ANP, with intravenous caerulein plus intraductal glycodeoxycholic acid. Control animals and rats with pancreatitis were randomized to be given intravenous CM or saline. MAIN OUTCOME MEASURE: Diffuse reflectance spectroscopy was used to measure the index of hemoglobin content and oxygen saturation in pancreatic tissues in vivo. RESULTS: Oxygen saturation of hemoglobin was increased in animals with mild acute pancreatitis (AP) (mean [+/- SEM], 58.7% +/- 1.2% vs 55.2% +/- 1.5% in control animals; P < .05) and was decreased in animals with ANP (51.2% +/- 1.2% vs 55.2% +/- 1.5%; P < .05). Fifteen minutes after the infusion of CM, oxygen saturation of hemoglobin significantly decreased further in animals with ANP (51.4% +/- 1.8% before infusion of CM vs 46.1% +/- 1.7% at 15 minutes; P < .05) and remained significantly below the comparable group receiving intravenous saline for the entire 60-minute test. This decrement was not observed in animals with ANP given saline or in animals with mild AP or in control animals after infusion of saline or CM. The index of hemoglobin content remained unchanged throughout the experiment in all groups. CONCLUSIONS: The prolonged reduction of oxygen saturation of hemoglobin in the pancreas following the administration of intravenous CM in rats with severe ANP indicates that CM impairs the pancreatic microcirculation in necrotizing forms of AP. This may explain our previous finding that CM increases pancreatic injury and mortality in rodents with ANP, and it underlines our concern that the use of contrast-enhanced computed tomography early in human AP may promote the evolution of pancreatic necrosis.

Intravenous contrast medium accentuates the severity of acute necrotizing pancreatitis in the rat.

BACKGROUND/AIMS: Contrast-enhanced computed tomography (CECT) is used to show areas of decreased pancreatic perfusion in severe acute pancreatitis (AP). To evaluate possible adverse effects of the contrast medium (CM) on the course of AP, the impact of intravenous CM in AP of graded severity in the rat was studied. METHODS: Pancreatitis of three levels of severity was induced in Sprague-Dawley rats with intravenous cerulein hyperstimulation plus time- and pressure-controlled intraductal infusion of saline or glycodeoxycholic acid. At 7 hours, control and pancreatitis animals received intravenous ionic CM, nonionic CM, or saline. The principal outcome measures were 24-hour survival, trypsinogen activation peptides (TAP) in ascites, and histological acinar necrosis score. RESULTS: There was no measurable effect of CM on the index features in control animals or animals with mild or moderate AP. In severe AP, CM caused a significant increase in mortality, ascites TAP, and necrosis score. CONCLUSIONS: Intravenous CM increases pancreatic injury when administered early in the course of severe experimental AP. Because CM may convert borderline ischemia to irreversible necrosis, CECT performed early in pancreatitis to show poor perfusion and predict areas of necrosis may depict a self-fulfilling prophecy. Early CECT should be reconsidered and perhaps avoided.

Bacteriology of the anal wound after open hemorrhoidectomy. Qualitative and quantitative analysis.

The purpose of this study is to analyze the size of the bacterial colonies in anal wounds after open hemorrhoidectomy. Twenty patients were studied during predetermined postoperative time periods. Material was collected from the surface and from within the tissue of each patient's three open wounds, intraoperatively, on the 6th, 13th and 20th postoperative days for bacteriologic examination in aerobic, microaerophilic, and anaerobic media. The bacterium most commonly identified was Escherichia coli, followed by Staphylococcus aureus and Staphylococcus epidermidis. Pseudomonas aeruginosa, Enterococcus faecalis, Klebsiella pneumoniae, Proteus vulgaris, and Proteus mirabilis were also identified. Critical indexes of colonization were present since the intraoperative stage (greater than 10(5) bacteria/g of tissue and greater than 10(6) bacteria/ml); obligate anaerobic bacteria were not identified; neither the species nor the number of bacteria, even when critical indexes were present, prevented proper healing. The same bacteria were not necessarily present on the surface and in the tissue; the bacterial load observed among the three wounds (left lateral, right posterior, and right anterior), was the same.

[Chilaiditi syndrome associated the volvulus of the transverse colon]. / Síndrome de Chilaiditi associada a volvo do colo transverso.

The hepatodiaphragmatic interposition of the colon (Chilaiditi's Syndrome) and associated volvulus of the transverse colon is a rare cause of mechanical intestinal obstruction. The preoperative diagnosis is extremely difficult. We report a 26-year-old- male case, symptomatic since childhood, whose diagnosis by barium enema was confirmed surgically in Hospital Universitário de Taubaté. He underwent a transversectomy, and presented an intestinal obstruction in the post-operative period. Two reoperations were required. He has remained well, with outpatient supervision.

Efficacy of various Bacillus thuringiensis var. israelensis formulations against Psorophora columbiae larvae as assessed in small rice plots, 1984-88.

Granular, liquid and briquette formulations of Bacillus thuringiensis var. israelensis were tested in small rice plots during 1984-88 against Psorophora columbiae larvae. Vectobac AS, Skeetal G, Teknar HPD, ABG 6172, ABG 6188, ABG 6193, ABG 6197, ABG 6199, ABG 6138F and ABG 6221 provided excellent control at high dosages and good control (generally greater than 85%) at relatively low concentrations. ABG 6221 and ABG 6172 provided excellent control at low concentrations. Additional testing of these formulations will be required to ascertain specific lower limits such that more economical larval mosquito control can be obtained.

Activities of four insect growth regulator formulations of fenoxycarb against Psorophora columbiae larvae.

Four formulations of fenoxycarb were evaluated at dosages of 0.022 and 0.011 kg ai/ha against Psorophora columbiae larvae in rice plots. Granular formulations, at both rates, provided moderate to excellent control of larvae introduced within 24 h posttreatment. A 1.0% fenoxycarb/200 ITU B.t.i. granule provided 86.2% reduction of emergence from larvae introduced at 120 h posttreatment. Aside from this formulation residual activity was lacking. The liquid formulation performed moderately well at the high rate against larvae introduced within 24 h; however, residual activity rapidly diminished.

Efficacy of fenoxycarb (Pictyl) against Psorophora columbiae in Arkansas ricefields.

The IGR, fenoxycarb was effective against mosquitoes in both small rice plots and commercial ricefields in southeast Arkansas at the rate of 10 g AI/ha. It adequately controlled Psorophora columbiae populations. This compound shows excellent promise as a tool in effective IPM schemes against Ps. columbiae larvae in Arkansas rice fields by acting as a direct control, and possibly by indirectly increasing their vulnerability to natural controls.

[Cystadenoma of the pancreas. Various aspects of the diagnosis and surgical management adopted in 3 cases]. / Cistoadenoma do pâncreas. Aspectos do diagnóstico e da conduta cirúrgica adotados em três casos.

The authors report three cases of cystadenoma of the pancreas. Two cases were serouscystadenoma and one case was mucouscystadenoma. The best diagnostic procedures were computed axial tomography and ultrasonography. Decisions regarding operation depend on three factors: the patient's general conditions, site of the tumor and hystologic pattern. In the first case the elderly patient had the tumor in the head of the pancreas which had led to biliary obstruction. To establish satisfactory biliary drainage a biliodigestive anastomosis was used. The other two cases were younger patients with large protruding abdominal mass in the epigastrium and mesogastrium by a tumor of the body and tail of the pancreas. In these cases we opted for body pancreatectomy and splenectomy. Since the serouscystadenoma doesn't have the malignant potential that the mucouscystadenoma has, the surgical procedure can be different from the surgical resection used for the treatment of pancreatic cystadenoma.