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A Hirner

Publications and source records attributed to A Hirner.

123 records · Page 7Linked to original sources

Differential diagnosis of early opacification of the portal vein and its tributaries during arteriography.

Twenty-two cases with communication of an artery and the portal vein or one of its tributaries are discussed. Four conditions in which relatively significant arterio-portal shunts may exist can be differentiated: (1) angiodysplasias or arteriovenous malformations, (2) cirrhosis of the liver and inflammatory lesions, (3) traumatic and postoperative lesions, and (4) benign and malignant tumors. The significance of the portal vein's early opacification during arteriographic examinations of the abdominal organs is discussed, and the findings are compared to those reported in the literature.

Arteriovenous Fistula↗

[Giant cavernous hemangioma of the liver. Case report and review of the literature (author's transl)].

The cavernous hemangioma of the liver is frequently seen as small tumor without any symptoms, but only rarely its diameter is more than 4 cm (161 cases in world literature). We can report on an additional patient. The peculiarities in this case were the tumor size, the presence of numerous phleboliths and the contrasting of the tumor taking place mainly from the venous part of the vascular bed of the liver. The main indication for a surgical intervention is the danger of rupture, but disturbances of the coagulation as well as intestinal suppression symptoms have also to be taken into consideration. The intraoperative tactics ought to be a standardised resection of the liver. The cavernous hemangioma must be differentiated from the hemangioendothelium: this usually occurs in children, causes cardiac failure due to a. v. shunts, and responds to conservative therapy (corticosteroids, radio-therapy).

Adult↗

[Hyperkinetic portal hypertension. Arterioportal fistula: problems--case reports--review of the literature].

Hyperkinetic portal hypertension is caused by pathological arterioportal shunts. Clinical differentiation is necessary between extrahepatic fistulas, splenoportal hypertension (arteriovenous anastomoses at the level of the pre-penicilary arteries) and intrahepatic fistulas in "active" cirrhosis and malignant tumors. This paper reports the clinical and angiographic features of eight patients with this type of fistula. A review of the literature is also presented (144 cases). Because of the severity of this disease, surgical intervention is necessary. The surgical technique depends on the organ-related necessity of vascular preservation.

Adult↗

Acute rejection in allogeneic rodent small bowel transplantation causes smooth muscle dysfunction via an inflammatory response within the intestinal muscularis.

INTRODUCTION: Isogeneic intestinal transplantation elicits an inflammatory response within the intestinal muscularis that is associated with dysmotility. Usually the inflammation and the postoperative motor dysfunction resolve within a few days after small bowel transplantation (SBTx). However, the onset of acute rejection in allogeneic SBTx is again associated with dysmotility. We hypothesized that dysmotility during acute rejection is based on coexpression of kinetically active mediators by the alloreactive leucocyte infiltrate. MATERIALS AND METHODS: Rat SBTx (BN to Lew and BN to BN) was performed without immunosuppression. Animals were sacrificed at 1, 4, and 7 days after SBTx. Leukocyte infiltration was investigated in muscularis whole mounts by immunohistochemistry. Mediator mRNA expression was determined by reverse transcriptase polymerase chain reaction. Muscle contractility was assessed in a standard organ bath. RESULTS: Transplanted animals showed a significant inflammatory response within the muscularis at day 1 after SBTx. However, allogeneic transplanted animals exhibited a significant second inflammatory peak at day 7 (mRNA induction: iNOS 150-fold; tumor necrosis factor-alpha 18-fold; interferon-gamma 397-fold), parallel to the onset of rejection. This change was associated with a significant leukocyte infiltration. Compared to controls, allogeneic transplanted animals showed a 29% decrease in smooth muscle contractility on days 1 and 4 and a 71% decrease of contractility on postoperative day 7. CONCLUSIONS: The motor dysfunction of transplanted small bowel during acute rejection is associated with an inflammatory reaction in the intestinal muscularis. The initial unspecific inflammation process immediately after transplantation is reactivated and intensified during acute rejection.

Animals↗

Mechanism and impact of organ harvesting and ischemia-reperfusion injury within the graft muscularis in rat small bowel transplantation.

INTRODUCTION: Inflammatory events within the gut muscularis contribute to dysmotility. We hypothesized that manipulation during organ harvesting initiated an inflammatory response via muscularis macrophages and that this cascade was amplified during reperfusion. METHODS: Small bowel transplantation was performed in Lewis rats. To investigate the impact of organ harvesting on muscularis inflammation, cold whole-body perfusion was performed after versus prior to organ harvesting. The role of macrophages was investigated by transplantation of the macrophage-depleted gut. Leukocyte infiltration was investigated in muscularis whole mounts. Mediator mRNA expression was determined by real-time reverse transcriptase polymerase chain reaction. Contractility was assessed in a standard organ bath. RESULTS: Organ harvesting and ischemia-reperfusion induced leukocyte recruitment and mRNA upregulation in the muscularis: interleukin-6 12217-fold, monocyte chemoattractant protein-1 62-fold, ICAM-1 12-fold, cyclooxygenase-2: 8-fold, iNOS: 150-fold. Although organ harvesting with cold ischemia prevented early gene expression, peak expression at 3-hour reperfusion was not changed by modification of the harvesting technique. Compared to controls, transplanted animals showed a 63% decrease in smooth muscle contractility. In contrast, transplanted macrophage-depleted gut exhibited significantly fewer leukocytes and only a 16% decrease in contractility. CONCLUSIONS: Gut manipulation during organ harvesting initiates an inflammatory response within the muscularis that is massively intensified during reperfusion. This change contributes to muscular dysfunction. Furthermore, the results suggested that resident macrophages play a key role in initiating this process.

Animals↗

Fas receptor is upregulated in livers from non-heart-beating donors.

Cell injury in livers from non-heart-beating donors (NHBDs) is not only caused by necrosis, but it is increasingly being recognized that apoptotic transformation contributes to postischemic cell death. It remains unclear which pathways lead to apoptosis. We suggested that apoptosis in NHBD livers might be mediated by the Fas receptor. Therefore the aim of our study was the detection and quantification of the Fas receptor, Fas mRNA and apoptosis in NHBD livers. Livers of male Wistar rats were harvested either from heart-beating donors (control, n = 15) or 30 min after cardiac arrest from NHBDs (n = 15). All livers were stored in University of Wisconsin solution for 24 h at 4 degrees C, and reperfused using a recirculating model with oxygenated Krebs-Henseleit buffer for 120 min at 37 degrees C. Conventional signs of cell damage, such as enzyme release and bile production, showed an elevated nonspecific cell injury in NHBD livers. The immunohistochemical staining of Fas antigen expression revealed a 7% rate of Fas receptor-expressing hepatocytes in the control group, but a considerable increase up to 38% in the NHBD group. No Fas antigen expression was detected on sinusoidal endothelial cells. Real-time RT-PCR detected an approximately eightfold elevated concentration of Fas mRNA transcripts in NHBD livers. We conclude that upregulation of the Fas receptor on hepatocytes in NHBDs will prime these cells to eventually undergo apoptosis upon reperfusion in vivo. Therefore, therapeutic modulation of the Fas pathway must be considered as a new strategy in order to additionally protect NHBD livers which are otherwise prone to parenchymal apoptosis.

Animals↗

Lipid peroxidation as additional marker in patients with colorectal cancer. Results of a preliminary study.

BACKGROUND AND AIMS: Up to now, various tumor markers have been proposed for the detection of the onset of malignant cell transformation or the better follow-up of cancer patients. The aim of the present study is to investigate the diagnostic value of systemic lipid peroxidation as an additional evaluative tool in the follow-up of surgical patients with colorectal cancer in combination to the clinically routine tumor markers carcinoembryonic antigen (CEA) and carcinoantigen 19-9 (CA 19-9). PATIENTS AND METHODS: 36 patients with a colorectal carcinoma were included in this study. Blood samples were collected 1 day prior to the operation, 10 days and 1 year after the operation. Oxygen free radical mediated lipid peroxidation was determined by measurement of thiobarbituric acid-reactive substances in the same serum that were used for the determination of tumor markers. RESULTS: Compared to control values, a highly significant increase of lipid peroxidation was found in the serum of all colorectal carcinoma patients up to the first 10 postoperative days. Differentiation of the patients, according to the T-stage, showed a marked and more obvious tendency towards higher serum lipid peroxides with increased tumor stage when compared to the conventional tumor markers. One year postoperatively the serum levels of lipid peroxidation returned to nearly normal values. Also the conventional tumor markers CEA and CA 19-9 showed a relative rise in the levels with the respective tumor stage, but differences were only statistically significant in the highest T-categories. CONCLUSION: After curative resection of the tumor, the level of systemic lipid peroxides decreases to normal values. We conclude from these results that the tumor is the primary cause of the increased systemic lipid peroxides.

Adult↗

Indocyanine green fluorescence measurement of intestinal transit and gut perfusion after intestinal manipulation.

BACKGROUND AND AIMS: Postoperative ileus is a common and poorly understood problem of abdominal surgery. The aim of this study was to measure postoperative intestinal transit and to evaluate bowel wall perfusion by a novel in vivo indocyanine green (ICG)-fluorescence measurement following intestinal manipulation (IM). METHODS: Rats underwent a simple intestinal manipulation. Myeloperoxidase-positive cells in the muscularis were stained with the Hanker-Yates reaction and quantified histochemically. Bowel wall perfusion was determined directly and 24 h postoperatively using a laser-fluorescence detection unit. Intestinal transit was visualized 24 h after IM. RESULTS: IM resulted in a massive infiltration (155-fold) of neutrophils into the intestinal muscularis 24 h postoperatively. Bowel wall perfusion significantly decreased directly and 24 h following surgery (29 and 59%, respectively). Gastrointestinal transit was similarly impaired and showed a reduction to 40% of the control values 24 h after IM. CONCLUSION: IM of the rat small intestine caused an impairment in bowel wall perfusion and microcirculation and a significant decrease in gastrointestinal transit. The ICG fluorescence measurement using the described system proved to be a simple and reliable method to evaluate intestinal transit and bowel wall microcirculation in vivo.

Animals↗

Evaluation of cholesterol absorption in rats using markers labeled with stable isotopes. Effect of complete bile diversion.

BACKGROUND/AIMS: An easily performed method to measure cholesterol absorption with isotope labeled cholesterol and beta-sitostanol in humans is described. The first aim of the study was to show whether this method can also be used in rats. Secondly, to see whether complete bile diversion results in a complete loss of cholesterol absorption. METHODOLOGY: Cholesterol absorption was evaluated in rats by the constant isotope feeding method using [2H6]cholesterol and [2H4]sitostanol as markers. Fecal samples were analyzed by gas-chromatography/mass spectrometry. RESULTS: In 8 rats with intact enterohepatic circulation of bile acids, cholesterol absorption averaged 61 (3% (SD) (range: 54-69%)). Complete bile diversion was followed by an almost total loss of cholesterol absorption (5.5+/-0.6%, range: 2.4-6.9%, n=7). CONCLUSIONS: The results indicate that deuterated cholesterol and deuterated sitostanol are reliable markers for measurement of cholesterol absorption in rats and that bile acids are essential for cholesterol absorption.

Animals↗