Umbilical Hernia Incarceration: A Complication of Medical Therapy of Ascites

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/73352/1/j.1572-0241.1983.tb01875.x.pd

Blood flow and distribution in the canine pancreas

Because of a tripartite arterial inflow, accurate determination of canine pancreatic blood flow (Qp) in experimental studies remains problematic. Assessment of blood flow using a single electromagnetic flow probe on the anterior pancreaticoduodenal artery (APDA) was compared to the radiolabeled microsphere method. Distribution of Qp was based on microsphere density. Qp determined simultaneously with the flow probe technique and the microsphere method were 86 +/- 17 and 23 +/- 8 ml/min, respectively, (P Qp measured by the flow probe increased to 94 +/- 27 ml/min (NS) and decreased to 19 +/- 4 ml/min (NS) using microspheres. Intrapancreatic distribution of Qp was not significantly altered by occlusion of the SA and PPDA. Intrapancreatic arterial collateral is adequate to maintain blood flow to the entire pancreas even when arterial inflow is restricted to the APDA. Flow probe determinations of Qp are artifactually high because they include flow to the duodenum and may also be subject to methodologic error.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/26591/1/0000132.pd

The effect of various resuscitative regimens on hemorrhagic shock in puppies

Since shock secondary to hemorrhage is not infrequently encountered in the pediatric patient, a puppy model was devised to help measure and monitor cardiovascular and metabolic changes that occur before and after resuscitation from hypovolemic shock (mean arterial pressure of 50 mm Hg for 1 hr). Three resuscitation protocols were compared: whole blood (replacement: shed) 1:1, 5% albumin in Ringer's lactate 1:1, and Ringer's lactate 3:1. All dogs survived the experiment and responded similarly during the shock period. Thermal dilution cardiac output rose in all groups after resuscitation; however, in the Ringer's lactate and 5% albumin groups, cardiac output was statistically greater than that observed in the blood group. In all groups, pH and blood pressure approached but did not return completely to baseline levels after resuscitation. In addition, early resuscitation demonstrated a further decrease in pH ("hidden acidosis") before it began to return toward normal as resuscitation progressed. This study suggests that the infusion of large volumes of Ringer's lactate or 5% albumin in Ringer's lactate are equally efficacious in the treatment of hemorrhage. However, 5% albumin seems to be preferable because it allows infusion of a smaller quantity of electrolyte solution with equivalent physiologic benefits.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/22801/1/0000358.pd

Pancreatic response to crystalloid resuscitation in experimental pancreatitis

Restoration and maintenance of intravascular volume is crucial in acute pancreatitis to prevent hypotension and ensure normal organ perfusion. This study evaluated the hemodynamic and metabolic effects of adequate versus inadequate fluid replacement on the pancreas in a canine model of acute experimental pancreatitis. Bile-trypsin pancreatitis (BTP) was induced in 14 conditioned mongrel dogs. Lactated Ringer's solution was administered intravenously at high (HIR) and low (LIR) infusion rates (6.5 and 1.75 ml/kg/hr, respectively) to 7 dogs each for 4 h. Seven sham-operated controls (CON) received lactated Ringer's at 6.5 ml/kg/hr for 3 hr. Mean arterial pressure remained unchanged in all groups. Central venous pressure decreased in the LIR group (P P QP) decreased in the LIR group (73%) to a significantly greater extent than in the HIR (23%) and CON (8%) groups, and in the HIR group significantly more than in the CON group. The fall in pancreatic oxygen consumption (O2CP) in both the pancreatitis groups was significant compared to the rise in the CON group. Final changes in QP and O2CP from baseline were significant only in the LIR group. We conclude that inadequate crystalloid replacement after BTP results in a progressive fall in QP and O2CP. Vigorous fluid replacement incompletely prevents these effects.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/26524/1/0000063.pd

Differential effects of portal diversion on hepatocyte function (HF) and hepatic reticuloendothelial cell (HRES) activity in the dog

End-to-side portocaval shunts (PCS) were constructed in six dogs to evaluate the effect of complete portal blood flow diversion on hepatocellular structure and function, hepatic reticuloendothelial (RE) activity, and serum opsonic activity (OA). RE activity remained normal after PCS despite a 40% reduction in estimated hepatic blood flow. Tissue distribution of injected colloid shifted away from liver to spleen, lung, and bone marrow. OA decreased to 40% of baseline values 6 weeks after PCS and remained low. Postshunt changes in hepatic morphology primarily affected hepatocytes and included deglycogenation and loss of rough endoplasmic reticulum. Significant changes in Kupffer cell morphology were not observed. Complete portal flow diversion in the dog caused profound alterations in hepatocellular structure and function without compromising Kupffer cell phagocytic and metabolic activity. Kupffer cells may be less dependent than hepatocytes upon hepatotrophic factors contained in portal blood. OA did not correlate with changes in vascular lipid clearance, suggesting that either phagocytosis of RES test lipid in the dog is not dependent on prior opsonization, or that the assay used was neither sensitive nor specific enough to measure a critical opsonic threshold required for effective phagocytosis.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/23877/1/0000116.pd

Pseudolymphoma of colon

A case of pseudolymphoma of the colon is reported. Radiographically and endoscopically the lesion could not be conclusively distinguished from malignant neoplasm, particularly lymphoma or segmental colitis, thus necessitating right hemicolectomy. Careful histological examination established the diagnosis of pseudolymphoma with pathologic features identical to the focal form of pseudolymphoma more commonly observed in the stomach.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/48154/1/261_2005_Article_BF01948094.pd

Enterooxyntin release from isolated perfused canine jejunum

A humoral factor may mediate the intestinal phase of gastric acid secretion. An ex vivo perfused segment of canine jejunum maintained by an oxygenated asanguinous physiologic perfusate was used to test for release of an enterooxyntin (EO) in response to balloon distention at 30 mm Hg for 15 min. Gastric acid secretion in guinea pig fundic mucosa was determined indirectly by a quantitative cytochemical bioassay (CBA) of oxyntic cell hydroxyl ion production (HIP). An increase in the optical density (OD) caused by the cytochemical stain in the oxyntic cells reflects HIP, an index of acid secretion. Basal OD for segments with distention was 16.6 +/- 0.53 and for those without 15.5 +/- 0.68 (NS). Results are expressed as mean change of OD from basal (mean [Delta]OD +/- SEM). EO caused greater stimulation of HIP than gastrin or histamine. EO was heat stable. Trichloroacetic acid treatment decreased EO activity as did pronase digestion suggesting that EO is composed of one or more peptides. Conclusion: EO, an acid secretagogue, is a humoral agent probably composed of one or more peptides and is released by small bowel distention. Mechanical distention of the small bowel may be an important mechanism for the perpetuation of gastric acid secretion. The ex vivo perfused jejunal segment in conjunction with the CBA are ideal tools with which to study mechanisms of release of EO and the mechanism of action of EO on the oxyntic cell.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/25235/1/0000677.pd

Effects of portacaval shunt and portacaval transposition on hepatocellular and hepatic reticuloendothelial cell activity in the dog

Quantitative reduction of portal blood flow following a portacaval shunt (PCS) adversely affects hepatocyte function, but does not alter HRES activity[1.]. To determine whether similar changes occur after qualitative alteration of portal blood flow, portacaval transpositions (PCT) were constructed in six conditioned mongrel dogs. Estimated hepatic blood flow (EHBF) was determined scintigraphically by the rate of hepatic uptake of a 500-[mu]Ci dose of 99mTc-sulfur colloid (Tsc). Hepatic reticuloendothelial cell (RES) phagocytic (PI) and degradative (DI) indices were calculated from the half-time blood disappearance of 131I-labeled RES test lipid emulsion, and the half-time urine appearance of free 131I, respectively. Opsonic activity (OI) was determined by gelatin latex particle agglutination and normalized to control values. Hepatocellular function was assessed by serial determinations of albumin (Alb), and pyruvic and glutamic oxaloacetic transaminases (SGPT and SGOT). All studies were performed prior to and at 3, 6, and 9 weeks following PCS or PCT. Conclusions: In the dog, neither PCS nor PCT adversely affected HRES activity. Hepatocellular function and OI remained unchanged following PCT but deteriorated significantly after PCS. Observed changes in hepatocyte function and OI following PCS suggest that hepatocellular integrity and serum opsonic activity may be interrelated.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/24838/1/0000264.pd

MEN I pancreas: A histological and immunohistochemical study

The spectrum and extent of islet cell histopathological findings in patients with multiple endocrine neoplasia, type I (MEN I) syndrome has never been clearly defined. Although some patients have discreet tumors causing clinically evident syndromes, others may have no symptoms until metastatic islet cell carcinoma is apparent. Whether diffuse islet cell disease occurs in all patients with grossly apparent tumors is not known. This study is an attempt to define both the functional and anatomical extent of islet cell disease and its relationship with the clinical course of patients with MEN I syndrome. The resected specimens of pancreas from 14 patients with MEN I syndrome were evaluated for hyperplasia, nesidioblastosis, multiple tumors, and evidence of malignancy. In 12 cases, specimens consisted of distal pancreas and, in 2 cases, the entire pancreas was available. Multiple sections were taken from each specimen. Immunoperoxidase staining was done for gastrin, pancreatic polypeptide, glucagon, serotonin, VIP, somatostatin, and neuron-specific enolase in sections of 24 tumors from 10 patients. Five of the 10 patients with Zollinger-Ellison syndrome underwent total gastrectomy and 3 others underwent only pancreatic procedures to control their acid hypersecretion. The following is concluded. All MEN I patients with pancreatic neoplasms have diffuse islet cell involvement consisting of nesidioblastosis, micro- and macronodular hyperplasia. Some tumors produce multiple hormones and these patients are at risk to develop new tumors, but complete excision of grossly apparent tumors may result in long-term control of the endocrinopathy present. This is particularly true for patients with insulinoma and hypoglycemia. Selected patients with gastrinoma may also be considered for excision of their islet cell tumor(s) without concomitant gastrectomy, especially if transhepatic venous sampling demonstrates a single site of excess gastrin production. However, if transhepatic venous sampling demonstrates diffuse sources of hypergastrinemia, a local pancreatic procedure will invariably be unsuccessful. Total pancreatectomy in MEN I patients with disease localized to the pancreas is the only curative surgical procedure but is rarely indicated. L'histopathologie des cellules insulaires pancréatiques des malades qui présentent un syndrome MEN I n'a jamais été parfaitement définie. Si certains parmi eux sont porteurs de petites tumeurs qui se manifestent par des syndromes cliniques patents, d'autres n'accusent aucun symptôme avant que des métastases néoplasiques ne se manifestent. En particulier, on ne sait pas si les altérations des cellules insulaires sont diffuses quand les malades présentent des tumeurs évidentes. Cette étude a pour but de définir à la fois l'importance anatomique et l'importance fonctionnelle de la maladie insulaire par rapport à son expression clinique chez les sujets concernés par ce syndrome. Pour ce faire, des spécimens provenant de 14 malades atteints du syndrome MEN I ont été étudiés eu égard à l'hyperplasie, à la nésidioblastose, à la multiplicité des îlots tumoraux, à la malignité. Dans 12 cas, les spécimens répondaient au pancréas distal, dans 2 cas à la totalité du pancréas. De multiples coupes furent pratiquées au niveau de chaque pièce soumise à l'examen. L'imprégnation à l'immunoperoxidase concerna les coupes de 24 tumeurs provenant de 10 patients. Cinq des 10 malades qui présentaient un syndrome de Zollinger-Ellison avaient subi une gastrectomie totale et 3 une intervention pancréatique pour contrôler leur hypersécrétion acide. Les conclusions tirées de cette étude furent les suivantes: tous les malades accusant un syndrome MEN I et porteurs d'un néopolasme pancréatique présentaient des lésions insulaires diffuses répondant à une nésidioblastose, à une hyperplasie micronodulaire et macronodulaire. Quelques tumeurs produisaient de multiples hormones: gastrine, polypeptide pancréatique, glucagon, sérotonine, V.I.P., somatostatine, testées par la méthode. Il résulte de ces constatations que les risques de récidive tumorale après exérèse complète des tumeurs évidentes ne sont pas à écarter, encore que l'exérèse permette de contrôler longtemps l'endocrinopathie. Ceci est particulièrement vrai pour les insulinomes hypoglycémiants. En ce qui concerne les gastrinomes, leur exérèse peut être suffisante, en particulier lorsque les prélèvements veineux étagés montrent qu'ils sont uniques; la gastrectomie concomitante est alors inutile. En revanche, lorsque la gastrine est trouvée en excès au niveau de multiples échantillons veineux, l'exérèse tumorale est insuffisante et la pancréatectomie totale représente l'intervention indispensable; en fait, son indication est rare. La variedad del espectro de la histopatología de las células insulares en pacientes con sindrome de neoplasias endocrinas múltiples tipo I (NEM I) todavía no ha sido claramente definido. Aún cuando algunos pacientes poseen tumores discretos que causan síndromes clínicamente evidentes, otros pueden no exhibir sintomatología alguna hasta cuando se hace evidente un carcinoma metastásico de células insulares. No se sabe si hay enfermedad difusa de las células insulares en todo paciente con tumores macroscópicamente aparentes, ni además se conoce con qué frecuencia se desarrollan nuevos tumores en pacientes con síndrome NEM I después de resección local o de pancreatectomía parcial para tumores primarios de células insulares. El presente estudio intenta definir la extensión funcional y anatómica de la enfermedad de las células insulares y su relación con la evolución clínica en pacientes con el síndrome NEM I.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/41313/1/268_2005_Article_BF01654938.pd

Identification of Novel Clinical Factors Associated with Hepatic Fat Accumulation in Extreme Obesity

Objectives. The accumulation of lipids stored as excess triglycerides in the liver (steatosis) is highly prevalent in obesity and has been associated with several clinical characteristics, but most studies have been based on relatively small sample sizes using a limited set of variables. We sought to identify clinical factors associated with liver fat accumulation in a large cohort of patients with extreme obesity. Methods. We analyzed 2929 patients undergoing intraoperative liver biopsy during a primary bariatric surgery. Univariate and multivariate regression modeling was used to identify associations with over 200 clinical variables with the presence of any fat in the liver and with moderate to severe versus mild fat accumulation. Results. A total of 19 data elements were associated with the presence of liver fat and 11 with severity of liver fat including ALT and AST, plasma lipid, glucose, and iron metabolism variables, several medications and laboratory measures, and sleep apnea. The accuracy of a multiple logistic regression model for presence of liver fat was 81% and for severity of liver fat accumulation was 77%. Conclusions. A limited set of clinical factors can be used to model hepatic fat accumulation with moderate accuracy and may provide potential mechanistic insights in the setting of extreme obesity