Search

Objective: To investigate the role of oxygen free radicals in the induction of apoptosis in non-heart-beating donor (NHBD) livers, and if superoxide dismutase (SOD) ameliorates these alterations. Methods: Rat livers were perfused via the portal vein with histidine/tryptophan/α-ketoglutarate solution from heart-beating donors (HBD) or 60-min warm ischemia from NHBD, with or without the addition of SOD. After 24 h, cold storage livers were evaluated by isolated reperfusion. Results: NHBD showed significantly higher enzyme leakage and elevated portal venous pressure (PVP) versus HBD. Bile and total adenine nucleotides (TAN) were significantly decreased. Apoptosis was prominent in sinusoidal lining cells, coupled with strong nitrotyrosine staining (NTR). The concentrations of nitric oxide and lipoperoxides were largely increased. SOD medication reduced hepatic enzyme release by 30% and lipoperoxides by nearly 50%. Apoptosis and NTR were significantly decreased, and PVP was strikingly reduced to normal values. A 3-fold enhancement in bile production and 1.5-fold increase in TAN of the liver tissue were also observed. Conclusion: NHBD livers are prone to severe reoxygenation injury promoted by oxygen free radicals, massive nitrite oxide production and peroxynitrite-induced apoptosis within the sinusoids. Antioxidant medication with SOD should be considered as a useful means of preserving NHBD livers. Copyright © 2008 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Background and Aims: The aim of this study was to analyze intestinal integrity after temporary abdominal wall repair with absorbable mesh. Methods: Rats underwent abdominal wall repair with absorbable mesh or sham operation. Myeloperoxidase-positive cells in the intestinal muscularis were histochemically quantified. Intestinal transit was visualized 48 h after surgery. Local and systemic inflammatory response was measured with TNF-α and IL-6 ELISA as well as malondialdehyde (MDA) expression in serum and peritoneal fluid. Results: Neutrophil count of the intestinal muscularis revealed that infiltration in the mesh-implanted and in the mesh-free animals 48 h postoperatively was similar. Gastrointestinal transit was similarly unaffected 48 h after surgery, with or without mesh implantation. TNF-α, IL-6 and MDA concentration in serum and peritoneal fluid showed no significant differences between the two groups. Conclusion: Intestinal contractility and local and systemic inflammatory response remained unaffected. Therefore, absorbable mesh augmentation is a safe and reliable method for temporary repair of the abdominal wall without affecting the intestinal integrity. Copyright © 2008 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Purpose: The purpose of this study was to investigate the presence of lymphatic invasion detected by D2-40 immunostaining compared to conventional hematoxylin-eosin (HE) staining in primary colorectal cancer (CRC) and the development of focal new lymphangiogenesis and peritumoral lymphatic proliferation in relation to the tumor stages. Additionally, we analyzed the relation of peritumoral inflammatory reaction (PIR) to tumor stages in CRC. The identification of new categories of patients with high-risk CRC would be very helpful in improving treatment strategies and patient outcome especially in early CRC. Patients and Method: Biopsies were taken from 41 patients with colorectal adenocarcinomas at different stages of disease. Immunohistochemistry was performed on paraffin-embedded sections. First, the whole section was screened for the presence of lymphatic invasion and PIR with routine HE staining. After analysis of the HE-stained slides, the slides were destained and reused for immunohistochemistry with the D2-40 monoclonal antibody. D2-40-immunostained sections were screened for the presence of lymphatic invasion, the proliferation of lymphatic vessels and focally newly developed lymph vessels. Results: Using the D2-40 antibody for immunostaining, our results demonstrate a significantly higher detection (p < 0.05) of lymphatic vessel invasion compared to routine HE staining in primary CRC. 22% more patients with lymphatic vessel invasion could be identified compared to routine HE staining, especially in node-negative tumor stage (UICC II). The positive predictive value of lymphatic invasion evaluated by D2-40 immunostaining to predict lymph node metastasis is 92% (negative predictive value 81%). High PIR was shown in UICC stage I and II. These infiltrations were rarely seen in UICC stage III and were absent in UICC stage IV. Higher UICC tumor stage is associated with a higher rate of focally newly developed lymphatic vessels. In UICC stage I we found peritumoral lymphatic vessel proliferation only in one case (14%) and in UICC stage II no case was found. 47% of the cases in UICC stage III and 50% of the cases in UICC stage IV showed focal peritumoral lymphatic vessel proliferation. Conclusions: Immunostaining with D2-40 significantly increased the detection rate of lymphatic invasion compared to conventional HE staining in primary CRC. The D2-40 antibody specific for lymphatic endothelium cells has the potential for a prognostic marker in early stage CRC. Further prospective studies are necessary to evaluate the prognostic value of lymphatic invasion and the induction of tumor lymphangiogenesis and its role in human cancer progression. Copyright © 2006 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Background/Aims: In an ovine meniscal repair model, the patellofemoral (PF) osteoarthritis due to a non-sutured tear or failed repair was investigated. Methods: A radial meniscus tear was either sutured with polydioxanone (PDS), with a slow degrading polylactide long-term suture(LTS) or left without treatment. Knee joint cartilage in the PF and medial compartment was evaluated compared to normal knees (healthy controls). Results: Retropatellar osteoarthritis in the non-sutured and sutured animals was intense in contrast to the control knees after 6 months in all groups (p < 0.001), and after 12 months in the PDS group (p < 0.001), LTS group and non-sutured animals (p < 0.05). Conclusion: Non-sutured meniscus tears and failed repair lead fast to intense PF osteoarthritis corresponding with tibial damage of the injured compartment. Copyright © 2006 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

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. Copyright © 2004 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Carnitine is an essential cofactor in the fatty acid transfer to the mitochondria. Recently it has been applied to ameliorate ischemia-reperfusion (I/R) injury of several organs. frequently reported. The aim of this study was to elucidate the effect of exogenous carnitine to protect the liver tissue from warm ischemia-reperfusion injury. Although carnitine administration ameliorated hepatic blood flow during reperfusion period, researchers could not prove a protective effect to the normal livers against warm I/R injury.

Organ donor shortage has led to reconsideration for the use of non heart beating donors (NHBDs). The present study was aimed at investigating the putative role of the adenosine A2 receptor for graft viability after cold preservation of NHBD livers in a preclinical large animal model. Cardiac arrest was electrically induced in German Landrace pigs. After 30 minutes the livers were perfused by gravity via the portal vein with 3L of HTK at 4 degree Celsius to which the selective adenosine A2 receptor agonist CGS 21680 was added in half of the experiments. All livers were then stored in HTK for 4-5 hours at 4 degree Celsius and transplanted orthotopically into weight matched litter mates.