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Objective The impact of stent design on venous patency is not well studied. The purpose of this study was to investigate the effect of stent material burden on endothelial coverage of stented venous segments, which may contribute to vessel healing and patency. Methods Segmented self expanding bare nitinol stents (18 × 50 mm) comprising 5 mm long attached metallic rings separated by 2, 5, or 8 mm gaps were implanted in the inferior vena cava (IVC) of 10 sheep. These stents were designed and manufactured for the purposes of this study. At six, 12, and 24 weeks after implantation the animals were euthanised and the stented vessels harvested for histomorphometric analysis. Three sections from the metallic part as well as the gaps between the struts were reviewed for quantification of endothelialisation after six, 12, and 24 weeks. The intimal thickness over and between the stent struts was measured. The endothelialisation score (graded from 1 for complete luminal endothelialisation to 5 for absence of endothelial cells) was determined. Results All stents were successfully deployed and all 10 sheep survived until the time of harvesting. Macroscopic inspection after 24 weeks showed only partial endothelialisation over stents with 2 mm and 5 mm skipped segments, whereas the stents with 8 mm skipped segments were totally incorporated into the vein wall. After 24 weeks, the mean (SD) neointimal thicknesses over stent struts with 2 mm, 5 mm, and 8 mm skipped segments were 254.0 (51.6), 182.2 (98.1), and 194.6 (101.1) μm, respectively. Comparison of endothelialisation scores of stents over time showed statistically significantly better endothelialisation over stents with 8 mm gaps after 12 and 24 weeks. Conclusion Stent designs providing structural support to veins with larger gaps between the scaffold material appear to lead to faster and more complete endothelialisation as well as a thinner intimal layer.

International journal of molecular sciences 23(9), 5272 (2022). doi:10.3390/ijms23095272 special issue: "Special Issue "Molecular Frontiers in Transplantation-Induced Ischemia Reperfusion Injury" / Special Issue Editor: Dr. Raphaël Thuillier, Guest Editor", Published by Molecular Diversity Preservation International, Basel

ApoE abnormality represents a well-known risk factor for cardiovascular diseases. Beyond its role in lipid metabolism, novel studies demonstrate a complex involvement of apoE in membrane homeostasis and signaling as well as in nuclear transcription. Due to the large spread of apoE isoforms in the human population, there is a need to understand the apoE’s role in pathological processes. Our study aims to dissect the involvement of apoE in heart failure. We showed that apoE-deficient rats present multiple organ damages (kidney, liver, lung and spleen) besides the known predisposition for obesity and affected lipid metabolism (two-fold increase in tissular damages in liver and one-fold increase in kidney, lung and spleen). Heart tissue also showed significant morphological changes in apoE−/− rats, mostly after a high-fat diet. Interestingly, the right ventricle of apoE−/− rats fed a high-fat diet showed more damage and affected collagen content (~60% less total collagen content and double increase in collagen1/collagen3 ratio) compared with the left ventricle (no significant differences in total collagen content or collagen1/collagen3 ratio). In patients, we were able to find a correlation between the presence of ε4 allele and cardiomyopathy (χ2 = 10.244, p = 0.001), but also with right ventricle dysfunction with decreased TAPSE (15.3 ± 2.63 mm in ε4-allele-presenting patients vs. 19.8 ± 3.58 mm if the ε4 allele is absent, p &lt, 0.0001*) and increased in systolic pulmonary artery pressure (50.44 ± 16.47 mmHg in ε4-allele-presenting patients vs. 40.68 ± 15.94 mmHg if the ε4 allele is absent, p = 0.0019). Our results confirm that the presence of the ε4 allele is a lipid-metabolism-independent risk factor for heart failure. Moreover, we show for the first time that the presence of the ε4 allele is associated with right ventricle dysfunction, implying different regulatory mechanisms of fibroblasts and the extracellular matrix in both ventricles. This is essential to be considered and thoroughly investigated before the design of therapeutical strategies for patients with heart failure.

Hydraulic fracturing (fracking) chemicals are used to maximize the extraction of hard-to-reach underground energy resources. Large amounts of fracking fluid could escape to the surrounding environments, including underground and surface water resources, during the chemical mixing stage of the hydraulic fracturing water cycle due to equipment failure or human error. However, the impact of pollution resulting from operational discharges is difficult to assess in aquatic ecosystems. In this study, pathological investigations, chromosomal aberrations, DNA damage, and biochemical and hematological parameters were used to evaluate the effects of such chemicals on Nile tilapia. Chromosomal aberrations are considered very sensitive genetic markers of exposure to genotoxic chemicals and are used as indicators of DNA damage. The appearance of different types of chromosomal aberrations (gaps and breaks) due to chemical exposure was significantly reduced by treatment with spirulina. Various deleterious findings in Nile tilapia, in the current study, could attributed to the presence of fracking chemicals in the aquatic environment. However, the presence of spirulina in the diet reduced the hazards of such chemicals. In addition, cytogenetic studies in the current work revealed the importance of spirulina in ameliorating the genotoxic effects of a mixture of some chemicals used in fracking.

Gut microbes 13(1), 1-21 (2021). doi:10.1080/19490976.2020.1854008, Published by Landes Bioscience, Austin, Tex.

Upon the demand of a private fish farmer, this study was applied to assess the influence of electro-fishing adopted by some Egyptian fish farmers on the fish welfare and quality. Therefore, a total of 60 Nile tilapia (Oreochromis niloticus) were sampled; from which 30 were stunned by electrofishing and the remainders by conventional fishing. Biochemical analysis (oxidative stress and energy status), meat quality based on total bacterial count (TBC) and pathological alterations were assessed. Biochemical analysis in both liver and muscle tissue showed that electro-stunned fish exhibited low oxidative stress and high energy status. Meat of electro-stunned fish showed an acceptable limit of TBC (Max. limit 107) while the histopathological examination revealed various tissue reactions. These were in the form of congestion in branchial, hepatoportal, brain and splenic blood vessels with edema in brain and pericardium. In addition, there was mild inflammatory reaction together with the presence of eosinophilic granular cells and perivascular melanophores aggregation in both branchial and muscular tissue. As a consequence of this work, we recommend the use of electrofishing method in Egypt after modifying the current tool by reducing applied voltage. Further studies and more optimization are needed to cover both fish farmers and animal welfare issues, and take in consideration the human safety precautions.

The aim of this study was to compare two variants of a novel polycarbonate polyurethane prosthesis with polyethylene terephthalate (Dacron) prosthesis in an established sheep model of carotid patch angioplasty. Two variants of the polycarbonate polyurethane prosthesis were used: (1) Polycarbonate polyurethane equal (PCU-e) prosthesis consisted of a multilayered porous structure with equal internal and external layers; (2) Polycarbonate polyurethane with more porous inner layers (PCU-mp) prosthesis had more porous inner layers than external layers. Carotid patch angioplasty was performed in 12 sheep: in six sheep, the PCU-e variant and in the other six sheep, the PCU-mp variant was implanted. Dacron patches were implanted in the contralateral carotid artery of all sheep as a control. Half of the animals with each polycarbonate polyurethane variant were euthanized after two weeks and the other half after eight weeks. Cellular infiltration, endothelialization, and neointimal hyperplasia were examined. All grafts were patent, and no thrombus was seen in any of the harvested arteries. The pores of all the three patch materials allowed infiltration of inflammatory cells, capillaries, and connective tissue. After eight weeks, a nearly complete endothelialization was visible in all patch groups without an obvious difference between the three patch materials. The neointima was thinner in the PCU patches (PCU-e: 56 +/- 13 mu m, PCU-mp: 119 +/- 60 mu m) when compared to Dacron patches (156 +/- 64 mu m) after two weeks. After 8 weeks, a further neointimal growth was detectable, without any significant difference of neointimal thickness between the three patch materials (Dacron: 274 +/- 82 mu m, PCU-e: 324 +/- 98 mu m, PCU-mp: 235 +/- 59 mu m). With the novel polycarbonate polyurethane patch materials, we achieved promising functional and morphological results with 100% patency and nearly complete endothelialization. Our findings showed at least a non-inferiority of the novel polycarbonate polyurethane patch material compared to Dacron. There were no significant differences detected between the two polycarbonate polyurethane patch variants.

Background The long-term outcome of intestinal transplantations is still not favorable, which is partly due to the intestinal susceptibility to ischemia. There are several indications that the inflammatory response to ischemia-reperfusion injury is mediated by cyclooxygenases and that their inhibition may be associated with improved organ function. The aim of this study was to analyze if cyclooxygenase (COX) inhibitors could improve the early posttransplant outcome after orthotopic small bowel transplantation. Methods Small bowel transplantation was performed between rats to test the impact of nonselective (Piroxicam), preferential (Meloxicam), and selective COX-2 inhibitors (Parecoxib). The donor intestines were either perfused and stored with inhibitor or had inhibitor administered intravenously after transplantation. Results Using COX inhibitors, a sequential increase of posttransplantation intestinal integrity could be shown, with Parecoxib the least effective and Meloxicam the most effective treatment. These differences were in line with the downregulation of COX-2 activity by the inhibitors. Functionally, the same tendency could be seen in diminished expression of proinflammatory molecules, decreased leucocyte inflammation, and significantly improved graft microcirculation. In most cases, the intravenous administration was more effective. However, the COX inhibitors used were shown to cause relevant hepatotoxicity under nearly all conditions, but particularly under intravenous administration. Only Meloxicam in histidine-tryptophan-ketoglutarate was demonstrated to be a safe drug without hepatotoxic side effects. Conclusions The activity of COX contributes to ischemia-reperfusion injury after intestinal transplantation. In this comparative study, the administration of the preferential COX-2 inhibitor Meloxicam via histidine-tryptophan-ketoglutarate showed the best graft-protective attributes and the lowest hepatotoxic side effects.

The Pringle maneuver (PM) has been widely used to control blood loss during liver resection. However, hepatic inflow occlusion can also result in hepatic ischemia&ndash, reperfusion injury (IRI), especially in patients with a cholestatic, fibrotic, or cirrhotic liver. Here we investigate a nitric oxide synthase (NOS) inhibitor N-Nitroarginine methyl ester (L-NAME) on IRI after the PM and partial hepatectomy of cholestatic livers induced by bile duct ligation (BDL) in rats. Control group (non-BDL/no treatment), BDL + T group (BDL/L-NAME treatment) and BDL group (BDL/no treatment) were analyzed. Cholestasis was induced by BDL in the L-NAME and BDL group and a 50% partial hepatectomy with PM was performed. L-NAME was injected before PM in the BDL + T group. Hepatocellular damage, portal venous flow, microcirculation, endothelial lining, and eNOS, iNOS, interleukin (IL)-6, and transforming growth factor-&beta, (TGF-&beta, ) were evaluated. Microcirculation of the liver in the BDL + T group tended to be higher. Liver damage and apoptotic index were significantly lower and Ki-67 labeling index was higher in the BDL + T group while iNOS and TGF-&beta, expression was decreased. This was corroborated by a better preserved endothelial lining. L-NAME attenuated IRI following PM and improved proliferation/regeneration of cholestatic livers. These positive effects were considered as the result of improved hepatic microcirculation, prevention of iNOS formation, and TGF-&beta, mRNA upregulation.

Scientific reports 9, 18153 (2019). doi:10.1038/s41598-019-54541-z, Published by Macmillan Publishers Limited, part of Springer Nature, [London]

Background In vascular surgery, novel synthetic prosthesis materials for patch-angioplasties, interpositions, bypasses and shunts are continuously under development and optimization. The characteristics of an ideal vascular prosthesis would display long-term patency, biocompatibility, durability, low porosity, lack of stich hole bleeding, ease of handling, kink resistance, infection resistance and reasonable costs. The aim of this study was to establish and report a reliable sheep model including potential pitfalls where those parameters could be analyzed. Before surgery, sheep were acclimatized for 4–8 weeks, during which parasite infections were treated and blood and serum parameters monitored. Twenty-four sheep underwent surgery, and carotid patch-angioplasties (n = 12), graft interpositions (n = 6) or arteriovenous prosthetic shunts (n = 6) were implanted. Half of the animals in each group were sacrificed after 2 weeks and the other half after 8 weeks. The implants were analyzed for patency, endothelialization, thrombogenicity and biocompatibility by clinical observation, blood flow measurement and pathological and histopathological (H&E, EvG) as well as immunohistochemical (Ki67, CD31) evaluations. Results Health monitoring of the sheep revealed a parasitic burden with endoparasites in all animals. Some animals showed thereby infestations in the bile duct causing fibrotic cholangitis with calcifications in the liver. In addition, sarcosporidia were detected in histopathological specimen of the heart in all animals. Parasitic burden correlated with blood counts and serum bilirubin levels. Both were significantly reduced by albendazole treatment within the acclimatization time. Patches, interposition grafts, and straight shunts were successfully implanted bilaterally in all animals. The total average operation time was 136 ± 21 min. Most animals (23/24) showed good patency rates and general condition after implantation. Pathological and histopathological/immunohistochemical analyses were suitable to determine thrombogenicity, endothelialization, cellular/fibroblastic proliferation, biocompatibility, inflammatory cell infiltration, and thickness of neointima in the prosthesis material. Conclusions We have developed a suitable experimental protocol with standardized and successful anesthesia- and surgical-procedures for patch-angioplasty, graft interposition, and arteriovenous prosthetic shunts. This sheep model allows testing of new prosthetic materials for biocompatibility, thrombogenicity, and endothelialization.

Due to the shortage of suitable organs, the demand for partial liver transplantation from living donors has increased worldwide. N-acetylcysteine (NAC) has shown protective effects as a free radical scavenger during hypothermic preservation and warm ischemia-reperfusion liver injury; however, no study has reported the effects in partial liver transplantation. The aim of this study was to analyze the impact of NAC on liver graft microcirculation and graft function after partial liver transplantation in rats.Orthotopic partial liver transplantations were performed in 40 rats following cold storage in histidine-tryptophan-ketoglutarate solution for 3 h with 20 mM NAC (NAC group, n = 20) or without (control group, n = 20). We assessed portal circulation, graft microcirculation, and biochemical analyses of plasma at 1, 3, 24, and 168 h after portal reperfusion.(Control versus NAC, median and range): Portal venous pressure was significantly lower with NAC (P = 0.03). Microcirculation measured by laser Doppler was significantly improved with NAC throughout the time course (P = 0.003). Alanine aminotransferase levels were significantly lower in the NAC group (P0.05). Total antioxidative capacity was significantly higher in the NAC group at 1 h after reperfusion (Trolox equivalents: median, 3 μM; range, 2.9-6.7 versus median, 16.45 μM; range, 10.4-18.8). Lipid peroxidation was significantly abrogated in the NAC group (median, 177.6 nmol/mL; range, 75.9-398.1 versus median, 71.5 nmol/mL; range, 58.5-79 at 3 h).This study showed that NAC treatment during cold storage resulted in improved microcirculation and preservation quality of partial liver graft likely because of enhanced antioxidant capacity and reduced lipid peroxidation.

This paper introduces an improved physiological animal model with diabetic Gottingen minipigs, which focuses on the application of human therapy devices and metabolic system analysis. Based on measurement data-sets collected by metabolic test procedures, a new mathematical minipig model is developed. The model consists of 16 differential equations and describes the diabetic porcine glucose metabolism according to the human model published by Sorensen. In the future, the mathematical model will be used as a basis for controller design and the physiological model for experimental control performance evaluation.

Background Due to the drastic shortage of organ donors, clinicians are increasingly considering the use of deceased after cardiac death donors (DCD). Compatible solutes like Ectoine and Hydroxyectoine are produced by extremophilic bacteria as a cell protectant to survive in harsh environments. We hypothesized that the addition of Hydroxyectoine to Histidine-Tryptophan-Ketoglutarate solution (HTK) could ameliorate cold ischemic preservation injury of DCD livers. Material and methods Rat livers were harvested from male Wistar rats weighing 250-300 g. Three experimental groups (n=5 per group) were studied: (1) CONTROLS: cold static storage in HTK for 24 h, (2) DCD: 30-min warm ischemia time and 24-h cold static storage in HTK, and (3) DCD+Hydroxyectoine: like DCD, but with 24-h cold static storage in HTK+Hydroxyectoine. Viability of the livers was assessed after 24 h of preservation by isolated perfusion for 45 min with oxygenated Krebs-Henseleit buffer solution. Results (mean ±SEM, Control vs. DCD vs. DCD+Hydroxyectoine) Parenchymal enzyme release was significantly lower in DCD+Hydroxyectoine compared to DCD (AST: 9±0.54; 56.8±2.05; 32.2±7.25 U/L, ALT: 9.5±0.5; 37.75±9.6; 17.5±4.17 U/L). Bile production at the end of 45 min reperfusion was significantly higher in DCD+Hydroxyectoine (5.16±1.32; 1.36±0.34; 10.75±2.24 µL/g liver weight/45 min). Malondialdehyde values were significantly lower in DCD+Hydroxyectoine (0.8±0.09, 1.14±0.18, 0.77±0.08 nmol/mL). Intercellular adhesion molecule-1 showed significantly lower values in DCD+Hydroxyectoine (219.07±51.79, 431.9±35.70, 205.2±37.71 pg/mL) and the portal venous pressure at 45 min was lower compared to DCD (20.41±0.12, 27.47±0.45, 22.08±0.78 mmHg). Conclusions Our data provide evidence for the beneficial role of Hydroxyectoine-modified HTK solution for the preservation of DCD livers compared to HTK.

BACKGROUND Steatotic livers are associated with poor graft function after transplantation. We investigated the effects of venous-systemic oxygen persufflation with nitric oxide gas (VSOP-NO) on steatotic partial livers after transplantation. METHODS Steatotic livers induced by fasting for 2 days and subsequent refeeding for 3 days with a fat-free, carbohydrate-rich diet were reduced in size by 50% and transplanted into Lewis rats after 3 hr of cold storage in histidine-tryptophan-ketoglutarate solution. Gaseous oxygen with nitric oxide (40 ppm) was insufflated into the grafts through the suprahepatic vena cava during cold storage (VSOP-NO group; n=20). Transplantation of cold-static stored steatotic and normal grafts served as controls (Steatotic-Control and Normal-Control, respectively; n=20 for each group). RESULTS The graft microcirculation and portal venous flow were increased by VSOP-NO compared with Steatotic-Control (P

The prognosis for recipients of small liver grafts is poor. The aim of this study was to determine the impact of venous systemic oxygen persufflation (VSOP) with nitric oxide (NO) gas for 30% partial liver preservation and transplantation in rats. After we determined optimal NO concentration as 40 ppm in vitro with the isolated perfused rat liver model, we assessed liver injury and regeneration in vivo at 1, 3, 24 and 168 h after transplantation in the following three groups after 3 h-cold storage (n = 20 per group): control group = static storage; VSOP group = oxygen persufflation and VSOP+NO group = oxygen with NO persufflation. The liver graft persufflation was achieved with medical gas via the suprahepatic vena cava; In comparison with control group after transplantation, VSOP+NO preservation (1) increased portal circulation, (2) reduced AST and ALT release, (3) upregulated hepatic endothelial NO synthase, (4) reduced hepatocyte and bileductule damage and (5) improved liver regeneration. These results suggest that gaseous oxygen with NO persufflation is a novel and safe preservation method for small partial liver grafts, not only alleviating graft injury but also improve liver regeneration after transplantation.

Background: Chemotherapy with L-asparaginase is associated with hepatotoxicity resulting in organ dysfunction in patients with preexisting liver disorders. This study investigated the protective effect of L-carnitine during chemotherapy in a steatotic rat liver model. Methods: Livers from nonsteatotic and steatotic rats were tested in an isolated liver reperfusion model adding L-asparaginase and L-carnitine to the reperfusate. Portal venous pressure (PVP), hepatic oxygen consumption, aspartate aminotransferase, lactate dehydrogenase, glutamate dehydrogenase and α-glutathione S-transferase levels were assessed. Further histopathological analysis was performed and cytotoxicity was verified in vitro. Results:L-Asparaginase induced toxicity in fatty livers whereas low toxicity was observed in normal livers. L-Carnitine induced a decline in PVP and oxygen consumption, and reduced parenchymal and mitochondrial damage in fatty livers. Cytotoxicity of L-asparaginase was not impaired by the presence of L-carnitine. Conclusions: Our study emphasizes the potential of L-carnitine to reduce L-asparaginase-induced hepatotoxicity in patients with preexisting liver disorders.

Background Due to the severe shortage of deceased donors, demand for living-donor liver transplantation (LDLT) has increased worldwide. Here, we compared POLYSOL, a recently developed low-viscosity preservation solution, and histidine-tryptophan-ketoglutarate (HTK) for cold storage of partial liver graft in this study. Methods Partial liver transplantations with 30% of the native liver were performed in Lewis rats. The graft livers were flushed with either HTK or POLYSOL (n = 25, respectively) and stored in the respective solution for 3 h at 5°C. Graft function was evaluated regarding ischemia-reperfusion injury and regeneration at 1, 3, 24, and 168 h after reperfusion. Results POLYSOL preservation resulted in improvement of portal venous flow (HTK versus POLYSOL; mean ± SEM: 16.8 ± 2.2 versus 21.6 ± 2.1 mL/min; P = 0.005), microcirculation (383 ± 63 versus 532 ± 64 Flux; P = 0.045), ALT (310.2 ± 56.1 versus 181.8 ± 17.0 IU/L; P = 0.0262), LDH (4052.4 ± 764.4 versus 2494.1 ± 410.0 IU/L; P = 0.0215), total bilirubin (21.6 ± 14.2 versus 4.0 ± 0.6 IU/L; P = 0.0236), malondialdehyde (100.0 ± 4.3 versus 69.2 ± 4.0 nmol/mL; P = 0.0015), as well histologic findings at 24 h. Liver regeneration was improved in POLYSOL with regards to liver weight (4.0 ± 0.2 versus 4.3 ± 0.3 g; P = 0.038) and Ki-67 labeling index (9.67 ± 2.17 versus 1.10 ± 0.14%; P

Hepatitis monthly 16(8), e36821 (2016). doi:10.5812/hepatmon.36821, Published by Tehran

Background/Aim: Worldwide shortage of donor organs has increased the use of donation after cardiac death (DCD). The aim of this study was to analyze the best time point for venous systemic oxygen persufflation (VSOP) supplemented with nitric oxide (NO) gas during the 1st and 24th hour of cold storage (CS) in warm ischemia (WI)-damaged experimental liver grafts. Materials and Methods: Liver grafts (n = 5) were retrieved after 30 min of WI induced by cardiac arrest and CS in histidine-tryptophan-ketoglutarate solution at 4°C. The 1st hour group was immediately persufflated with a VSOP plus NO (VSOP+NO) mixture for 1 h followed by 23 h of static CS (DCD+NO 1st hour). The 24th hour group entailed CS for 23 h followed by 1 h of VSOP+NO persufflation (DCD+NO 24th hour). CS livers without WI but with VSOP served as controls. CS livers with WI represented the fourth group (DCD). Viability of the liver grafts was assessed by normothermic isolated reperfusion for 45 min with oxygenated Krebs-Henseleit buffer. Results: Data are presented as mean ± SEM (control vs. DCD vs. DCD+NO 1st hour vs. DCD+NO 24th hour). After 45 min of reperfusion, the DCD+NO 1st hour group showed significantly lower aspartate aminotransferase (13.4 ± 5.3, 63.2 ± 17.3, 25.6 ± 3.9, and 82.8 ± 27.3 U/l) and lactate dehydrogenase levels (289.4 ± 41.2, 2,139.4 ± 542.7, 577.2 ± 117.2, and 2,429 ± 221.6 U/l). Malondialdehyde levels were significantly abrogated (1.0 ± 0.3, 2.7 ± 1, 1.0 ± 0, and 3.9 ± 1.2 nmol/ml). Significantly higher levels of portal venous pressure were recorded in the DCD+NO 24th hour group (12.0 ± 1, 21.2 ± 3.1, 16.1 ± 1, and 23.2 ± 3.5 mm Hg). NO levels were recorded after 5 min of reperfusion (1.42 ± 0.17, 1.8 ± 0.2, 2.7 ± 0.2, and 2.6 ± 0.1 μmol/l). Bile production levels showed no statistical significance (23.2 ± 3.8, 27.3 ± 1.8, 43.5 ± 18, and 31 ± 2.5 μl/45 min). Conclusion: Our results present the beneficial effects of NO combined with VSOP during the 1st hour of CS of WI-damaged experimental liver grafts.

BACKGROUND Results in small bowel transplantation are inferior compared to other solid organ transplantations, among other reasons, due to a specific vulnerability to ischemia/reperfusion injury. New strategies are needed to improve organ storage. Here we compare static cold storage in University of Wisconsin solution to storage supplemented with molecular oxygen gas insufflation. MATERIAL AND METHODS Rat small bowel was retrieved and either stored unoxygenated (UW) or oxygenated (UW+O2) for 18 h at 4°C. Biochemical parameters, mucosal function, Toll-like receptor upregulation, and parameters of structural integrity were evaluated following isolated reperfusion in vitro for 30 min at 37°C. RESULTS Oxygenation showed: ATP concentration was 82 times higher; lactate dehydrogenase release was continuously lower over 30 min; malondialdehyde, a final product of lipid peroxidation (UW+O2 vs. UW; 2.7±0.92 nmol/mL vs. 17.22±10.1 nmol/mL; P0.05) and nitric oxide concentration (0.87±0.27 µmol/L vs. 2.17±0.29 µmol/L; P0.001) were significantly lower; whereas mucosal functional integrity (galactose uptake) was better preserved (0.47±0.18 mg/dL vs. 0.35±0.05 mg/dL). Amelioration of tissue damage could be demonstrated by reduced apoptosis (3.3±1.2 AU vs. 28.4±10 AU; P0.05), and preserved subcellular integrity. Toll-like receptors were significantly less upregulated (TLR2 0.32±0.1 vs. 2.1±1.5-fold and TLR4 1.53±1.14 vs. 11.79±5.4-fold; P0.05). CONCLUSIONS Oxygenated storage is superior to standard storage in University of Wisconsin solution in terms of energetics, tissue damage, and mucosal integrity.

Ten dogs suffering from discospondylitis were treated by percutaneous discectomy and local and systemic antibiotic therapy. With fluoroscopic guidance, a cylinder 5 mm in diameter was removed from the centre of the intervertebral space, yielding a fenestration and decompressing the disc without producing any spinal instability. The causative bacteria were identified in nine of the 10 biopsy specimens, but in only three urine cultures and four blood cultures. In two cases, the antibiotics used initially had to be changed owing to the organisms' antibiotic resistance. The clinical signs of the dogs improved markedly after two to nine days (mean 4.2 days) and had resolved completely after five to 14 days (mean 9.1 days). In all the cases the disease could be classified histologically as either acute or chronic, and the disease was classified as chronic in one dog. No side effects were observed.

Purpose Recently, Apoliprotein E deficient (ApoE-/-) rats have been generated by genetic manipulation, while the bench-to-bedside relevance of this novel model for coronary stenosis research has not been elucidated. Here, we seek to characterize vascular inflammation and in-stent cross-sectional stenosis (ICS) development in the abdominal aorta of ApoE-/- rats. Methods Trans-abdominal aorta bare-metal stent (Multi-LinkMini Vision, Abbott Vascular Inc., Santa Clara, CA; 2.5 x 8 mm; 12 atm) implantation was performed in ApoE-/- rats (Sigma Aldrich Genetic Engineering, Saint Louis, MO). At 7 and 28 days, quantification of ICS, neointimal (NI) area, injury score and inflammation score was conducted using image analysis software (DISKUS, Hilgers, Königswinter). Blood serum analysis for Interleukin (IL)-6, -8 and -10 and for cholesterol levels was performed. Results Serum cholesterol levels were elevated in ApoE-/- rats (8.63±1.73mmol/l vs. 1.98±0.55mmol/l; p Conclusions In ApoE-/- rats, cholesterol levels as well as pro-inflammatory IL-6 and -8 are upregulated, while anti-inflammatory IL-10 is downregulated. Concomitantly, ApoE-/- rats develop increased ICS after abdominal stent implantation. This novel small animal model enables the characterization of distinctive molecular and mechanical ICS mechanisms in an atherogenic milieu that, notably, renders disposable any miniaturization of tested stents as opposed to mouse models.

World journal of hepatology 9(24), 1030-1039(2017). doi:10.4254/wjh.v9.i24.1030, Published by Beijing Baishideng BioMed Scientific Co., Beijing

Chemotherapy with L-asparaginase is associated with hepatotoxicity resulting in organ dysfunction in patients with preexisting liver disorders. This study investigated the protective effect of L-carnitine during chemotherapy in a steatotic rat liver model.Livers from nonsteatotic and steatotic rats were tested in an isolated liver reperfusion model adding L-asparaginase and L-carnitine to the reperfusate. Portal venous pressure (PVP), hepatic oxygen consumption, aspartate aminotransferase, lactate dehydrogenase, glutamate dehydrogenase and α-glutathione S-transferase levels were assessed. Further histopathological analysis was performed and cytotoxicity was verified in vitro.L-Asparaginase induced toxicity in fatty livers whereas low toxicity was observed in normal livers. L-Carnitine induced a decline in PVP and oxygen consumption, and reduced parenchymal and mitochondrial damage in fatty livers. Cytotoxicity of L-asparaginase was not impaired by the presence of L-carnitine.Our study emphasizes the potential of L-carnitine to reduce L-asparaginase-induced hepatotoxicity in patients with preexisting liver disorders.

Energy-based technologies for tissue sealing and cutting are increasingly supplementing current standards used for haemostasis and dissection during laparoscopic surgery. For their safe and efficacious use in clinical practice, these instruments have to guarantee sufficient burst resistance and low thermal damage to adjacent tissue in combination with good cutting characteristics.The novel laparoscopic, bipolar electrosurgical sealing and cutting instrument BiCision® was compared to a commercially available laparoscopic device (EnSeal(™)) on visceral and peripheral arteries and veins in an animal model.For all parameters investigated (burst pressure, cut quality, tissue adhering to the instrument, time needed to seal and cut the vessel and thermal damage), BiCision® was at least as good as EnSeal(™). Regarding the burst pressure, BiCision® was superior over EnSeal(™) in arteries: 600 mmHg (±478) versus 241 (±269) mmHg, respectively (p0.0001*). In veins, almost equivalent burst pressures of 155 ± 134 mmHg (BiCision®) and 173 ± 139 mmHg (EnSeal(™)) were obtained.BiCision® appeared to be as good as or even superior to EnSeal(™). Since EnSeal(™) has already been shown to be safe and has been successfully used in clinical practice, BiCision® is assumed to be as efficient and reliable as EnSeal(™) under pre-clinical conditions.

Annals of intensive care 2, S17 (2012). doi:10.1186/2110-5820-2-S1-S17 special issue: "Diagnosis and management of intra-abdominal hypertension and abdominal compartment syndrome", Published by Springer, Heidelberg

The increasing shortage of donor organs has led to the increasing use of organs from non-heart-beating donors. We aimed to assess the impact of venous systemic oxygen persufflation (VSOP) supplemented with nitric oxide (NO) gas during the cold storage (CS) of warm ischemia (WI)-damaged experimental liver grafts. Rat livers (n = 5 per group) were retrieved after 30 minutes of WI induced by cardiac arrest (the WI group) and were thereafter preserved for 24 hours by CS in histidine tryptophan ketoglutarate solution. During CS, gaseous oxygen was insufflated via the caval vein with 40 ppm NO (the VSOP-NO group) or without NO (the VSOP group). Cold-stored livers without WI served as controls. Liver viability was assessed after the preservation period by normothermic isolated reperfusion for 45 minutes with oxygenated Krebs-Henseleit buffer. After 45 minutes of reperfusion, the VSOP-NO-treated livers showed significantly lower alanine aminotransferase values than the WI-damaged livers (10.2 ± 0.2 versus 78.2 ± 14.6 IU/L), whereas the control livers showed no differences from the VSOP-NO-treated livers. The mitochondrial enzyme release was lower in the VSOP-NO group (4.0 ± 0.7 IU/L) versus the WI group (18.2 ± 4.9 IU/L). An increased portal vein pressure was observed throughout reperfusion (45 minutes) in the WI group (21.7 ± 0.2 mm Hg) versus the VSOP-NO group (12.2 ± 0.8 mm Hg) and the control group (19.9 ± 0.4 mm Hg). Furthermore, the NO concentration in the perfusate after 5 minutes of reperfusion was highest in the VSOP-NO group. The release of malondialdehyde into the perfusate was significantly reduced in the VSOP-NO group (0.9 ± 0.1 nmol/mL) versus the WI group (31.3 ± 5.3 nmol/mL). In conclusion, the resuscitation of livers after 30 minutes of WI to a level comparable to that of nonischemically damaged livers is possible with VSOP supplemented with NO gas. Moreover, the application of VSOP with NO minimizes the extent of injuries caused by oxygen free radicals during preservation.

In order to reduce the number of animal experiments, the use of non-heart-beating donors (NHBDs) from a commercial abattoir has been proposed. Since the use of slaughterhouse organs is legally not defined as animal experiment, this would fulfil international standards as an alternative to animal experiments. The development of intravascular thrombosis after cardiac arrest negatively impacts organ preservation and thus viability during ischaemic storage and reperfusion. A fibrinolytic preflush with streptokinase might overcome these limitations. Therefore, the functional and histomorphological integrity of kidneys preserved immediately with intact circulation (control group A) and kidneys preserved after cardiac arrest with a 30 min period of warm ischaemia (WI) (group B) was compared with kidneys preflushed with 12.5 kU/L (group C) or 50 kU/L streptokinase (group D) after 30 min WI prior to preservation. We could demonstrate that kidneys preflushed with 12.5 kU/L streptokinase (group C) performed better than those without streptokinase pretreatment after WI (group B). Parameters like oxygen consumption, perfusion pressure, laboratory values, lactate dehydrogenase level and lipidperoxidation were closer to that of the control (group A) than in groups B and D. The higher streptokinase concentration of 50 kU/L (group D) resulted histologically in a more pronounced tissue damage and an attenuated renal function, indicating toxic effects. On the basis of our results we believe streptokinase preflushed slaughterhouse kidneys to be an adequate alternative to organs from laboratory animals with the potential to further reduce the number of animal experiments.

Intra-abdominal hypertension (IAH) and abdominal compartment syndrome are increasingly observed in patients with severe acute pancreatitis (SAP). The aim of this study was to investigate the effects of IAH on pancreatic histology and ultrastructure in a porcine model. We examined 16 intubated and anesthetized domestic pigs with a mean body weight of 50.6 (SD, 3.8) kg. Using a CO2 pneumoperitoneum, the intra-abdominal pressure was increased to 30 mmHg for an investigation period of 6 or 12 h (each study group n = 6). In the control group, the intra-abdominal pressure remained 3.9 (SD, 5.4) mmHg for 12 h. Additional Ringer's solution was infused to maintain cardiac output at the level of controls. After the observation period, specimens were taken for histological and ultrastructural analysis, and animals were killed. Cardiac output did not change when compared with control. Histologically, mild- to moderate-grade necrosis was observed after 12 h of IAH. In the ultrastructural analysis, leukocyte infiltration and swelling of endothelial cells were found. In the acinar cells of the exocrine pancreas, endoplasmic reticulum was dilated, and necrosis was noticed. Mitochondrial damage manifested as cisternal destruction with formation of large vacuoles. In this porcine model, 6 and 12 h of IAH resulted in light-microscopical and ultrastructural changes comparable to pancreatitis in humans. As SAP is often accompanied by IAH, the finding of the underlying study suggests a vicious cycle in which IAH may worsen pancreatitis. Ultimately, these findings are in favor of a decompression in patients with SAP and IAH.

Objectives: To determine retrospectively the prognosis and outcome for dogs diagnosed with thoracolumbar intervertebral disc disease treated with partial percutaneous discectomy (PPD). Methods: Three hundred and thirty-one dogs presenting with symptoms of thoracolumbar intervertebral disc disease from 1998 to 2003 were treated with PPD. Diagnosis and location of intervertebral disc disease was confirmed by clinical examination, radiography, myelography and magnetic resonance imaging. PPD was performed via fluoroscopy-guided removal of a 5 mm bore cylinder out of the central intervertebral space. Results: Clinical success after surgery was achieved in 159 (88·8 per cent) grade II to IV patients and 58 (38·2 per cent) grade V patients. The mean (sd) time from percutaneous discectomy to first improvement was 8·3 (13·2) days. Clinical Significance: The PPD approach to the thoracolumbar spine involves minor trauma (yielding rapid recovery) and less pain, and produces results comparable with open fenestration. Consequently, this simple minimal invasive technique can be recommended as an alternative to the technique of fenestration and can be easily performed in addition to open surgical decompression techniques or prophylactically. However, it is not a replacement for surgical treatment in dogs with thoracolumbar disc disease that require removal of disc fragments causing spinal cord or nerve root compression.

According to a previous study, a pathologically increased intraabdominal pressure (IAP) reduces cardiac output (CO) and results in medium- to high-grade organ damage in a porcine model of the abdominal compartment syndrome (ACS). The purpose of this study was to evaluate whether fluid resuscitation can preserve organ integrity together with CO. We examined 12 domestic pigs with a mean body weight of 48 kg. We used a CO2 pneumoperitoneum to increase the IAP to 30 mmHg in 6 animals, and the others served as control group. The investigation period was 24 h. In addition to a standard infusion regimen, Ringer's solution was infused to maintain CO at the level of control animals. Hemodynamic parameters (ITBV, EVLW, MAP, CVP), urine output, inspiratory pressure, as well as serum parameters (e.g., ALT, lipase, AP, lactate, creatinine) were recorded. In the end histological examination of liver, bowel, kidney, and lung was performed. CO, ITBV, EVLW, and urine output did not change when compared with control. Fluid intake was increased (P0.01) when compared with control (10,570 +/- 1,928 vs. 3,918 +/- 1,042 mL). CVP, MAP, and inspiratory pressure were increased. Serum parameters did not change. Acidosis occurred in the study group. Liver, bowel, kidney, and lung displayed mean- to high-grade damage (P0.01). Although extensive fluid resuscitation preserved CO, diuresis, and serum parameters in this previously described model of the ACS, organ damage occurred. In the clinical regard, these results support decompressive treatment in the presence of pathologically high IAP despite "normalized" parameters.

Laparoscopic techniques are increasingly applied for the treatment of diverse gastrointestinal diseases. With regard to reports of a pronounced decrease of intra-abdominal blood flow with increasing intra-abdominal pressure, the present study investigates the impact of pressure and gas type on ischemia in small bowel anastomoses in the rat model. Laparotomy and ileoileal anastomosis were performed in 39 male Sprague-Dawley rats. A CO2 or helium pneumoperitoneum of 3 mm Hg or of 6 mm Hg was maintained before and after anastomoses. Rats in the control group received no pneumoperitoneum. Animals were sacrificed after 5 d, and the anastomotic region was explanted for subsequent histopathological examinations. In hematoxylin and eosin (HE)-stained sections, the Chiu score, villi configuration, and number of goblet cells were analyzed. Proliferation (Ki67) and expression of a matrix metalloproteinase (MMP-8) were examined by immunohistochemistry. Mucosal damage according to the scoring system by Chiu, the number of goblet cells, the villus length, the proliferation (Ki67), and the submucosal expression of MMP-8 was similar in all groups. Our results suggest that within a certain range of pressures and time, laparoscopic assisted surgery using CO2 pneumoperitoneum can be performed safely. Helium gas offers no advantages over CO2.

We report our results of partial lumbosacral laminectomy for treatment of canine Cauda equina Compression Syndrome due to a lumbosacral stenosis. Opposite to conventional techniques of dorsal laminectomy, only widening of the Spatium interarcuale is performed. This is achieved by exstirpation of the Lig. flavum and partial dorsal laminectomy of the first sacral segment. The Proc. spinosi and integrity of facet joints are fully maintained by this technique. In 96.5% of 86 dogs treated with this method relief of dorsal pressure and permanent rapid regression of clinical symptoms was achieved. In two cases recurrence of clinical symptoms was observed during follow up and one case showed no improvement at all. In conclusion partial dorsal laminectomy is a minimal invasive technique for treatment of Cauda equina compression syndrome expressed by pain reaction accompanied by minor neurological deficits caused by lumbosacral stenosis. Maintained spinal stability allows short reconvalescence and the unrestricted use of dogs immediately post operation.

Background Trauma, vascular lesions or peritonitis can cause an increase of the intra-abdominal pressure (IAP) or an abdominal compartment syndrome (ACS). Maintaining the cardiac output (CO) cannot prevent impairment of organ function. However, it is unknown, whether an IAP of 30 mmHg can lead to oragn damage within 6 an 12 h despite unchanged CO. Methods We examined 16 male pigs (50 kg, SD 1,8). Animals were ventilated volume controlled and analogue-sedated using ketamine and pentobarbital. Via CO2-pneumoperitoneum, IAD was increased to 30 mmHg for 6 and 12 h (each n = 6). In the control (n = 4) the IAP remained unchanged. Heartrate (HR), mean arterial pressure (MAP), central venous pressure (CVP), CO and peak inspiratory pressure (PIP) were continuously recorded. Additional to basic fluid replacement (2 ml/kg/h) crystalloid volume was given whenever continuously monitored CO was below control values. In the end, animals were given an overdose of pentobarbital and specimen were taken from lung, heart, kidney, liver stomach as well as small and large bowel. Damage of bowel specimen was classified according to Park whereas damage to other organs was classified as none, low, intermediate and high. Statistic analysis was performed using ANOVA and post-hoc analysis together with paired tests. A p Results A significant increase of CVP and PIP was found whereas the other haemodynamic data was not changed. Compared to control, an increased morphologic damage was found in lung, stomach (12 h), liver, bowel and kidney. The myocardium was statistically unchanged. Conclusion Even a short-termed increase of the IAP for 6 h results in morphologic organ impairment despite an unchanged CO. In the clinical regard, these results imply an immediate decompression in the presence of a critically increased IAP.

Anesthesia of the pig poses great problems for experimental animal-based research and particularly in shock research. In this study, five mechanically ventilated domestic pigs were given long-term anesthesia with a combination of ketamine plus pentobarbital. Circulatory parameters were recorded every 2 h via an arterial catheter placed in the right common carotid artery, a Swan-Gans thermodilution catheter (7F), that was placed in the pulmonary artery of the right middle-lobe in a wedge position through the external jugular vein, and another catheter in the internal jugular vein for measuring central venous pressure. Moreover, body weight, blood gases, pH, blood cells, electrolytes and serum enzymes were measured. Further serum traits as total protein and glucose and pathological alterations in different organs were recorded. The animals were observed for a period of 96 h and then killed painlessly. It was shown that pigs can survive 96-h anesthesia with the combination of ketamine and pentobarbital. Optimum, carefully controlled anesthesia did not impair the integrity of the regulatory mechanisms of circulation.

To investigate the effect of meloxicam on the gut-liver axis after cirrhotic liver resection.Forty-four male Wistar rats were assigned to three groups: (1) control group (CG); (2) bile duct ligation with meloxicam treatment (BDL + M); and (3) bile duct ligation without meloxicam treatment (BDL). Secondary biliary liver cirrhosis was induced via ligature of the bile duct in the BDL + M and BDL groups. After 2 wk, the animals underwent a 50% hepatectomy. In the BDL + M group 15 min prior to the hepatectomy, one single dose of meloxicam was administered. Parameters measured included: microcirculation of the liver and small bowel; portal venous flow (PVF); gastrointestinal (GI) transit; alanine aminotransferase (ALT); malondialdehyde; interleukin 6 (IL-6), transforming growth factor beta 1 (TGF-β1) and hypoxia-inducible factor 1 alpha (HIF-1α) levels; mRNA expression of cyclooxigenase-2 (COX-2), IL-6 and TGF-β1; liver and small bowel histology; immunohistochemical evaluation of hepatocyte and enterocyte proliferation with Ki-67 and COX-2 liver expression.Proliferative activity of hepatocytes after liver resection, liver flow and PVF were significantly higher in CG vs BDL + M and CG vs BDL group (P0.05), whereas one single dose of meloxicam ameliorated liver flow and proliferative activity of hepatocytes in BDL + M vs BDL group. COX-2 liver expression at 24 h observation time (OT), IL-6 concentration and mRNA IL-6 expression in the liver especially at 3 h OT, were significantly higher in BDL group when compared with the BDL + M and CG groups (P0.01, P0.001, P0.01, respectively). Liver and small bowel histology, according to a semi quantitative scoring system, showed better integrity in BDL + M and CG as compared to BDL group. ALT release and HIF-1α levels at 1 h OT were significantly higher in BDL + M compared to CG and BDL group (P0.001 and P0.01, respectively). Moreover, ALT release levels at 3 and 24 h OT were significantly higher in BDL group compared to CG, P0.01. GI transit, enterocyte proliferative activity and number of goblet cells were in favor of meloxicam treatment vs BDL group (P0.05, P0.001, P0.01, respectively). Additionally, villus length were higher in BDL + M as compared to BDL group.One single dose of meloxicam administered after cirrhotic liver resection was able to cause better function and integrity of the remaining liver and small bowel.