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G Otto

Publications and source records attributed to G Otto.

At least 181 records · Page 10Linked to original sources
PubMed1992

[Liver transplantation after trans-jugular intrahepatic portosystemic stent shunt].

Every third patient with parenchymal liver disease bleeds from esophageal varices. Treatment of this complication is of special interest with regard to liver transplantation which may become necessary later on. The mesocaval H-shunt excluded, surgical shunting results in technical and hemodynamic problems during transplantation. They may be avoided by the new approach of transjugular intrahepatic portosystemic stent shunt (TIPSS). We report our experience with liver transplantation in two patients after TIPSS.

Adult↗
PubMed1992

[Acute jugular engorgement in liver transplantation].

A 56-year-old patient with chronic liver failure underwent liver transplantation; a Denver shunt had been placed 6 months previously. Following an initially uneventful operative course, during fashioning of the proximal caval anastomosis in the anhepatic phase, the patient developed very marked jugular engorgement. The central venous pressure rose to 45 mmHg and this lasted some 15 min. With the opening of the venous anastomosis and placement of the liver in its anatomical site, the central venous pressure returned to normal values once again. It can be concluded that during fashioning of the anastomosis, both the right atrium and distal superior vena cava were obstructed. While normally not haemodynamically significant, in this case, however, the superior vena cava became more narrow by the routinely placed venous lines and the Denver shunt. This in turn, gave rise to this particular clinical manifestation.

Acute Disease↗
PubMed1991

Arterial steal: an unusual cause for hepatic hypoperfusion after liver transplantation.

Case reports of two patients with an unusual cause for a rapid increase in transaminases following liver transplantation are described. In the postoperative course, angiography revealed an arterial hypoperfusion of the liver due to a steal phenomenon with blood shunting from the hepatic to the splenic artery. In one case, the underlying pathophysiology was a pre-existing filiform stenosis of the celiac trunk with insufficient recruitment of arterial blood from the superior mesenteric artery via the pancreatic arcade. Adequate liver perfusion was restored by simple ligation of the common hepatic artery. In the other case, angiography showed an arteriovenous fistula formation of the splenic vessels and minimal blood flow through the hepatic vessels. This was successfully corrected by angiographic embolization of the splenic artery with metal coils. After therapeutic intervention, both patients rapidly recovered with excellent liver function.

Adult↗
PubMed1991

Transmission of Helicobacter spp. A challenge to the dogma of faecal-oral spread.

Faecal oral spread is claimed by many to be the mode of transmission of the gastric pathogen Helicobacter pylori. This idea is based not on experimental data but because the epidemiology of H. pylori infection resembles that of other pathogens known to be spread by the faecal-oral route. This is in spite of the observation that no-one has been successful in culturing H. pylori from human stool. In this study, a series of transmission experiments are reported on animals infected with the gastric spirilla, Helicobacter felis and 'Gastrospirillum hominis'. Germfree mice and rats infected with H. felis did not transmit their infection to uninoculated mice despite prolonged contact in the same cage nor could the bacterium be isolated from their intestinal contents. This was confirmed in specific pathogen free mice where infected dams did not pass the helicobacter to their progeny. Similarly, mice infected with a human isolate of 'Gastrospirillum hominis' did not transmit the infection while in close contact with uninoculated mice. In contrast, in a limited series of experiments, both H. pylori and H. felis were transmitted from infected gnotobiotic Beagle puppies to uninfected animals in the same enclosure. In addition, the gastric mucus from a cat with indigenous 'Gastrospirillum'-like organisms was infectious for mice, whereas faecal content from the same animal was not. It is suggested that the difference between the murine and canine experiments is that the dogs are more likely to have oral-oral contact than rodents. Unlike dogs, mice and rats do not vomit and are coprophagous. It is concluded that the case for faecal-oral spread of Helicobacter species is 'not proven' and that the inter-oral route is more likely.

Animals↗
PubMed1991

Rapid increase in the activity of enzymes of eicosanoid synthesis in hepatic and extrahepatic tissues after experimental liver transplantation.

Previous studies have demonstrated a marked release of prostanoids from hepatic tissue after liver grafting. In addition, eicosanoid synthesis was shown to be regulated at the level of key enzymes. The present study addressed changes of the local availability of these enzymes during and after porcine orthotopic liver transplantation. We determined kinetic parameters of cyclooxygenase (CO), the initial enzyme of prostaglandin synthesis, of prostacyclin and thromboxane synthase (PCS, TXS), two more peripheral enzymes, in microsomal preparations of hepatic and gluteal muscle biopsies, and the activity of 5-lipoxygenase (5-LO), the key enzyme of leukotriene synthesis. Maximal velocity (Vmax) of CO and PCS showed a 4-fold increase both in liver and gluteal muscle tissue 1 hr after reperfusion of the grafted liver and a more than 20-fold increase after 24 hr (P less than 0.001), whereas apparent affinities (Km) remained unchanged. In contrast, Vmax of TXS and the activity of 5-LO disclosed a striking increase only within the hepatic graft (P less than 0.001). No changes of enzymatic activity could be observed during donor operation, cold storage, and 5 min after reperfusion. Results were independent of the duration of preservation (3 hr and 20 hr with Euro-Collins) and the addition of Iloprost, a prostacyclin-analogue. These results suggest that after liver grafting, abnormalities at the level of local enzyme expression in hepatic and extrahepatic tissues might contribute to preservation damage and systemic injury of the host.

6-Ketoprostaglandin F1 alpha↗
PubMed1991

Biliary secretion of bile acids, lipids, and bilirubin by the transplanted liver. A quantitative study in patients on cyclosporine.

To investigate biliary secretion in liver-transplanted patients on cyclosporine treatment we used duodenal perfusion with a nonabsorbable marker. After an overnight fast, 4 women and 5 men were studied for 6 hr at least 6 weeks after orthotopic liver transplantation. The data were compared with those obtained in 6 healthy controls. All transplanted patients received immunosuppressive therapy (corticosteroids, azathioprine, and cyclosporine). Biliary secretion rates of healthy controls were: bile acids 1.58 +/- 0.67 mmol/hr, phospholipids 0.27 +/- 0.11 mmol/hr, cholesterol 0.11 +/- 0.01 mmol/hr, and bilirubin 18 +/- 0.7 mumol/hr (mean +/- SEM). Liver-transplanted patients excreted 2.60 +/- 0.4 mmol/hr bile acids, 0.56 +/- 0.08 mmol/hr phospholipids, 0.18 +/- 0.04 mmol/hr cholesterol, and 22.0 +/- 4.5 mumol/hr bilirubin. Analysis of individual bile acids revealed that in the bile of liver transplant patients the percentage of cholic acid was elevated, whereas that of deoxycholic acid was reduced as compared with controls. These findings indicate that in the transplanted liver under immunosuppressive therapy with cyclosporine biliary secretion of bile acids, lipids, and bilirubin is not reduced.

Adult↗
PubMed1991

Helicobacter felis gastritis in gnotobiotic rats: an animal model of Helicobacter pylori gastritis.

The gastric spirillum Helicobacter felis, originally isolated from the cat stomach, colonizes the stomachs of germfree rats. Studies were designed to examine the pathological and serological responses of germfree rats inoculated orally with H. felis. At 2 weeks postinoculation, the gastric mucosa of germfree rats had lymphocytes and eosinophils scattered in small foci throughout the subglandular region of the antrum. Small numbers of lymphocytes were present in the subglandular portion of the antral mucosa that focally extended through the lamina propria towards the luminal surface. Eight weeks postinoculation, the inflammation was confined to the antrum. It was characterized by increased numbers of lymphocytes and eosinophils in the subglandular areas, with focal aggregates of lymphocytes in the submucosa. Some lymphoid aggregates extended from the submucosa through the muscularis mucosa and lamina propria to the luminal surface. H. felis was demonstrated with the Warthin-Starry stain, bacterial culture, and urease assay, particularly in the antrum. H. felis also produced a significant immunoglobulin G antibody titer at 2, 4, and 8 weeks postinoculation as well as a transitory immunoglobulin M response at 2 to 4 weeks postinoculation. Contact control rats were not infected, inferring that fecal-oral spread of H. felis did not occur.

Animals↗
PubMed1991

Helicobacter mustelae-induced gastritis and elevated gastric pH in the ferret (Mustela putorius furo).

Helicobacter mustelae has been cultured from the stomachs of ferrets with chronic gastritis; the lesions in the stomach have many of the same histological features seen in H. pylori gastritis in humans. To determine whether H. mustelae-negative ferrets with normal gastric mucosa were susceptible to colonization and whether gastritis developed after infection, four H. mustelae-negative ferrets treated with cimetidine were inoculated orally on two successive days with 3 ml (1.5 x 10(8) CFU) of H. mustelae; eight age-matched H. mustelae-negative ferrets served as controls. All four ferrets became colonized; H. mustelae persisted through week 24 of the study, as determined by positive gastric culture, tissue urease, and Warthin-Starry staining of gastric tissue. Superficial gastritis developed in the oxyntic gastric mucosa, and a full-thickness gastritis, composed primarily of lymphocytes and plasma cells plus small numbers of neutrophils and eosinophils, was present in the antrum. The inflammation was accompanied by an elevation of immunoglobulin G antibody to H. mustelae. At 4 weeks post-inoculation, the four infected (experimental) ferrets developed an elevated gastric pH (4.0 to 5.2) for 2 weeks. The eight control ferrets did not have gastritis; H. mustelae could not be demonstrated in gastric tissue via culture, nor was there an immune response to the bacteria. In ferrets, H. mustelae readily colonizes the stomach and produces a gastritis, a significant immune response, and, like H. pylori infection in humans, a transient elevated gastric pH after Helicobacter infection.

Animals↗