953 resultados para Hepatic Ischaemia Reperfusion
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Background/Aims: Specific treatment of chronic hepatitis C is effective in 50% of patients, improving the]liver`s fibrosis, necroinflammatory changes and steatosis. However, in patients still viremic after treatment the extension of these benefits remains doubtful. The evolution of the disease in this group and its relationship to demographic data, biometric indices and time lapse between biopsies was evaluated. Methodology: In 141 patients, paired biopsies were classified and compared according to fibrosis grading. Necroinflammation, steatosis, demographic data (age and gender), body mass index (BMI) and time lapse between biopsies were compared with fibrosis grading. Results: The grade of fibrosis of the patients, after approximately 3.5 years time lapse between biopsies, could be classified into 4 groups; Improved: 29(20.0%), Unaltered: 64(45.0%), Worsened: 48(34%) and Cirrhotic: 14(9.93%). For necroinflammation, the Improved/Unaltered groups were statistically similar but different from the Worsened and Cirrhotic. The mean age, BMI and time lapse between biopsies were statistically similar in all groups. Steatosis occurred in 35 (24.82%) between biopsies and its incidence was reduced in the Worsened and Cirrhotic groups. Conclusions: Fibrosis turned into cirrhosis in a significant number of patients, after a short time lapse. The reverse correlation of steatosis to fibrosis and its occurrence during the time lapse between biopsies suggests it might induce hepatic necrosis and contribute to fibrogenesis.
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Background: Endoscopic sclerotherapy (ES) has been the standard treatment for children with idiopathic extrahepatic portal vein obstruction (EHPVO). Portosystemic shunts are indicated when variceal bleeding cannot be controlled by ES. Recently, mesenteric left portal vein bypass was indicated as a surgical intervention and preventative measure for hepatic dysfunction in children with long-term EHPVO. Nevertheless, there is a lack Of published data confirming the extent of hepatic dysfunction, hypersplenism, and physical development in children with long-term follow-up. Method: We retrospectively verified the long-term outcomes in 82 children with EHPVO treated with ES protocol, focusing on mortality, control of bleeding, hypersplenism, and consequent hepatic dysfunction. Results: Of the children, 56% were free from bleeding after the initiation of ES. The most frequent cause of rebleeding was gastric varices (30%). Four patients had recurrent bleeding from esophageal varices (4.6%). Four patients underwent surgery as a consequence of uncontrolled gastric varices. There were no deaths. Most patients showed good physical development. We observed a mild but statistically significant drop in factor V motion, as well as leukocyte and platelet count. Conclusion: Endoscopic sclerotherapy is an efficient treatment for children with EHPVO. The incidence of rebleeding is low, and there was no mortality. Children develop mild liver dysfunction and hypersplenism with long-term follow-up. Only a few patients manifest symptoms of hypersplenism, portal biliopathy, or liver dysfunction before adolescence. (C) 2009 Elsevier Inc. All rights reserved.
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The liver involvement in the human visceral leishmaniasis (VL) has been related to parasitism and activated Kupffer cells with further occasional fibrotic alterations, especially after long-term disease without treatment. However, fibrotic alterations have been reported after therapy, whose clinical finding is the persistence of hepatomegaly. Fibrotic involvement of the liver after therapy was never well understood, and the aim of this study was to evaluate this finding through ultrastructural and morphometric analysis. A case-control study was performed with 20 patients (15 cases and five controls). Cases included patients with persistent hepatomegaly (residual) after treatment of VL submitted to liver biopsy to exclude other causes of liver enlargement, including serum tests of viral hepatitis. The material was evaluated by electron microcopy allowing ultrastructural with morphometric analysis of medium portion of hepatic lobule. Narrow sinusoidal lumen and prominent Kupffer cells were found with insignificant alterations of hepatocytes, pit, and endothelial cells. On ultrastructural analysis, the enlargement of the space of Disse was due to fibrous collagen, increase of number of Ito cells, and nonfibrous extracellular matrix that were associated with Kupffer cells enlargement. Immunohistochemistry showed an intense expression of TGF-beta in patients with VL. These findings suggest a production of TGF-beta by Kupffer cells that resulted in the characteristic fibrotic involvement of the liver. Residual hepatomegaly in visceral leishmaniasis could result from sustained Kupffer cell activation with perihepatocytic fibrosis.
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Background: Androgenic anabolic steroids (AAS) are synthetic hormone derivatives of testosterone and are mainly used to enhance athletic performance and muscle mass, but medical applications also have been described. Short- and long-term side effects have been demonstrated in many organs, but the liver adverse effects are the most common and serious ones associated with AAS use. However, these effects have been supported by few clinical and experimental studies. Objective: To evaluate the hepatic function and structure after 5 wk of nandrolone decanoate administration at three different doses. Methods: Twenty-seven adult male Wistar rats were randomly assigned to the following groups: control, clinical, intermediate, and suprapharmacological doses of nandrolone decanoate during 5 wk. Results: The biochemical studies showed that nandrolone decanoate administration leads to a dose-dependent increase in serum levels of the aspartate aminotransferase (AST) (P < 0.05), alanine aminotransferase (ALT) (P < 0.01), and alkaline phosphatase (ALP) (P < 0.001), as well as a significant decrease in total proteins (P < 0.01), bilirubin (P < 0.05), total cholesterol and fractions (P < 0.05), and triglycerides (P < 0.05). Although a significant statistical difference was found for AST, ALT, and ALP when compared with the control group, their values remained within the normal range. The number of Kupffer cells was increased in the liver parenchyma (P < 0.05), and the content of collagen was increased in the central lobular vein wall, in the hepatic parenchyma, and in the portal space (P < 0.05). Conclusions: These results suggest that subchronic treatment with nandrolone decanoate, mainly administered at higher-than-clinical doses, are potentially deleterious to the liver, leading to incipient fibrosis.
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Hepatic progenitor cells (HPCs) are bipotential stem cells residing in human and animal livers that are able to differentiate towards the hepatocytic or cholangiocytic lineages. HPCs are present in both hepatocellular (HCC) and cholangiocellular carcinoma (CC) in humans; and a small percentage of HCC can originate from cancer stem cells. However, its distribution in canine liver tumour has not been studied. Herein, we searched for stem/progenitor cells in 13 HCC and 7 CC archived samples by immunohistochemical analysis. We found that both liver tumours presented a higher amount of K19-positive HPCs. Besides, 61.6% of HCC cases presented immature CD44-positive hepatocytes. Nevertheless, only two cases presented CD133-positive cells. As observed in humans, hepatic canine tumours presented activated HPCs, with important differentiation onto hepatocytes-like cells and minimal role of cancer stem cells on HCC. These findings reiterate the applicability of canine model in the search for new therapies before application in humans.
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Background. Sensitized patients (pts) may develop acute antibody-mediated rejection (AMR) due to preformed donor-specific antibodies, undetected by pre-transplant complement-dependent cytotoxicity (CDC) crossmatch (XM). We hypothesized that C4d staining in 1-h post-reperfusion biopsies (1-h Bx) could detect early complement activation in the renal allograft due to preformed donor-specific antibodies. Methods. To test this hypothesis, renal transplants (n = 229) performed between June 2005 and December 2007 were entered into a prospective study of 1-h Bx and stained for C4d by immunofluorescence. Transplants were performed against a negative T-cell CDC-XM with the exception of three cases with a positive B-cell XM. Results. All 229 1-h Bx stained negative for C4d. Fourteen pts (6%) developed AMR. None of the 14 protocol 1-h Bx stained positive for C4d in peritubular capillaries (PTC). However, all indication biopsies-that diagnosed AMR-performed at a median of 8 days after transplantation stained for C4d in PTC. Conclusions. These data show that C4d staining in 1-h Bx is, in general, not useful for the early detection of AMR when CDC-XM is negative.
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Introduction. The use of arterial grafts (AG) in pediatric orthotopic liver transplantation (OLT) is an alternative in cases of poor hepatic arterial inflow, small or anomalous recipient hepatic arteries, and retransplantations (re-OLT) due to hepatic artery thrombosis (HAT). AG have been crucial to the success of the procedure among younger children. Herein we have reported our experience with AG. Methods. We retrospectively reviewed data from June 1989 to June 2010 among OLT in which we used AG, analyzing indications, short-term complications, and long-term outcomes. Results. Among 437 pediatric OLT, 58 children required an AG. A common iliac artery interposition graft was used in 57 cases and a donor carotid artery in 1 case. In 38 children the graft was used primarily, including 94% (36/38) in which it was due to poor hepatic arterial inflow. Ductopenia syndromes (n = 14), biliary atresia (BA; n = 11), and fulminant hepatitis (n = 8) were the main preoperative diagnoses among these children. Their mean weight was 18.4 kg and mean age was 68 months. At the mean follow-up of 27 months, multiple-organ failure and primary graft nonfunction (PNF) were the short-term causes of death in 9 children (26.5%). Among the remaining 29 patients, 2 (6,8%) developed early graft thrombosis requiring re-OLT; 5 (17%) developed biliary complications, and 1 (3.4%) had asymptomatic arterial stenosis. In 20 children, a graft was used during retransplantation. The main indication was HAT (75%). BA (n = 15), ductopenia syndromes (n = 2), and primary sclerosing cholangitis (n = 2) were the main diagnoses. Their mean weight was 16.7 kg and age was 65 months. At a mean follow-up of 53 months, 7 children died due to multiple-organ failure or PNF. Among the remaining 13 patients, 3 developed biliary complications and 1 had arterial stenosis. No thrombosis was observed. Conclusion. The data suggested that use of an AG is useful alternative in pediatric OLT. The technique is safe with a low risk of thrombosis.
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We report the case of a 9-year-old boy with portal hypertension, due to Budd-Chiari syndrome, and retrohepatic inferior vena cava thrombosis, submitted to a transjugular intrahepatic portosystemic shunt (TIPS) by connecting the suprahepatic segment of the inferior vena cava directly to the portal vein. After 3 months, the withdrawal of anticoagulants promoted the thrombosis of the TIPS. At TIPS revision, thrombosis of the TIPS and the main portal vein and clots at the splenic and the superior mesenteric veins were found. Successful angiography treatment was performed by thrombolysis and balloon angioplasty of a severe stenosis at the distal edge of the stent.
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Background. Subsequent ischaemic episodes may induce renal resistance. P21 is a cell cycle inhibitor that may be induced by oxygen-free radicals and may have a protective effect in ischaemic acute kidney injury (AKI). This study aimed at evaluating the role of oxidative stress and p21 on tubular resistance in a model of acquired resistance after renal ischaemia and in isolated renal tubules. Methods. Wistar rats were divided into: Group 1-sham; Group 2-sham operated and after 2 days submitted to 45-min ischaemia; and Group 3-45-min ischaemia followed after 2 days by a second 45-min ischaemia. Plasma urea was evaluated on Days 0, 2 and 4. Serum creatinine, creatinine clearance and oxidants (thiobarbituric acid-reactive substances) were determined 48 h after the second procedure (Day 4). Histology, immunohistochemistry for lymphocytes (CD3), macrophages (ED1), proliferation (PCNA) and apoptosis (TUNEL) were also evaluated. Rat proximal tubules (PTs) were isolated by collagenase digestion and Percoll gradient from control rats and rats previously subjected to 35 min of ischaemia. PTs were submitted to 15-min hypoxia followed by 45-min reoxygenation. Cell injury was assessed by lactate dehydrogenase release and hydroperoxide production (xylenol orange). Results. Ischaemia induced AKI in Group 2 and 3 rats. Subsequent ischaemia did not aggravate renal injury, demonstrating renal resistance (Group 3). Renal function recovery was similar in Group 2 and 3. Plasma and urine oxidants were similar among in Group 2 and 3. Histology disclosed acute tubular necrosis in Group 2 and 3. Lymphocyte infiltrates were similar among all groups whereas macrophages infiltrate was greater in Group 3. Cell proliferation was greater in Group 2 compared with Group 3. Apoptosis was similar in groups 2 and 3. The p21 expression was increased only in Group 3 whereas it was similar in groups 1 and 2. PTs from the ischaemia group were sensitive to hypoxia but resistant to reoxygenation injury which was followed by lower hydroperoxide production compared to control PT. Conclusion. Renal resistance induced by ischaemia was associated with cell mechanism mediators involving oxidative stress and increased p21 expression.
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Background/purpose: The introduction of the piggyback technique for reconstruction of the liver outflow in reduced-size liver transplants for pediatric patients has increased the incidence of hepatic venous outflow block (HVOB). Here, we proposed a new technique for hepatic venous reconstruction in pediatric living-donor liver transplantation. Methods: Three techniques were used: direct anastomosis of the orifice of the donor hepatic veins and the orifice of the recipient hepatic veins (group 1); triangular anastomosis after creating a wide triangular orifice in the recipient inferior vena cava at the confluence of all the hepatic veins (group 2); and a new technique, which is a wide longitudinal anastomosis performed at the anterior wall of the inferior vena cava (group 3). Results: In groups 1 and 2, the incidences of HVOB were 27.7% and 5.7%, respectively. In group 3, no patient presented HVOB (P = .001). No difference was noted between groups 2 and 3. Conclusions: Hepatic venous reconstruction in pediatric living-donor liver transplantation must be preferentially performed by using a wide longitudinal incision at the anterior wall of the recipient inferior vena cava. As an alternative technique, triangulation of the recipient inferior vena cava, including the orifices of the 3 hepatic veins, may be used. Published by Elsevier Inc.
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Mutations in PKD1 cause the majority of cases of autosomal dominant polycystic kidney disease (ADPKD). Because polycystin 1 modulates cell proliferation, cell differentiation, and apoptosis, its lower biologic activity observed in ADPKD might influence the degree of injury after renal ischemia/reperfusion. We induced renal ischemia/reperfusion in 10- to 12-wk-old male noncystic Pkd1(+/-) and wild-type mice. Compared with wild-type mice, heterozygous mice had higher fractional excretions of sodium and potassium and higher serum creatinine after 48 h. In addition, in heterozygous mice, also cortical damage, rates of apoptosis, and inflammatory infiltration into the interstitium at time points out to 14 d after injury all increased, as well as cell proliferation at 48 h and 7 d. The mRNA and protein expression of p21 was lower in heterozygous mice than wild-type mice at 48 h. After 6 wk, we observed dilated tubules, microcysts, and increased renal fibrosis in heterozygotes. The early mortality of heterozygotes was significantly higher than that of wild-type mice when we extended the duration of ischemia from 32 to 35 min. In conclusion, ischemia/reperfusion induces a more severe injury in kidneys of Pkd1-haploin-sufficient mice, a process that apparently depends on a relative deficiency of p2l activity, tubular dilation, and microcyst formation. These data suggest the possibility that humans with ADPKD from PKD1 mutations may be at greater risk for damage from renal ischemia/reperfusion injury.
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Involvement of the celiac trunk and common hepatic artery are two of the most common forms of vascular invasion by tumours of the distal pancreas, and until recently this finding was considered a contra-indication to resection. We described a modified Appleby operation for locally advanced distal pancreatic cancer with compromised hepatic collateral flow that needed hepatic arterial revascularization, successfully accomplished by left external iliac-hepatic arterial bypass with Dacron prosthesis. Patient recovery was uneventful and he was discharged on the 10th postoperative day. Postoperative angio-CT disclosed a patent arterial bypass. Patient is well and asymptomatic 13 months after operation. At the time of this writing, postoperative CT scan showed no evidence of disease and CA 19-9 level is normal. There is a well established rationale to perform extended resection of pancreatic carcinomas that compromise vascular structures. Modified Appleby procedure can safely be performed, has oncological advantages to palliative procedures and provides relief of pain but is reserved for selected patients. Preservation of hepatic arterial flow has utmost importance to avoid hepatobiliary complications as liver necrosis, liver abscess, gallbladder necrosis or cholecystitis. In this case, hepatic revascularization was particularly challenging, but was successfully accomplished by left external iliac-hepatic arterial bypass. To our knowledge this type of arterial bypass has never been described so far in the English literature and its description may be important for surgeons dealing with advanced pancreatic cancer. (C) 2009 Elsevier Ltd. All rights reserved.
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Excessive free-radical production due to various bacterial components released during bacterial infection has been linked to cell death and tissue injury. Peroxynitrite is a highly reactive oxidant produced by the combination of nitric oxide (NO) and superoxide anion, which has been implicated in cell death and tissue injury in various forms of critical illness. Pharmacological decomposition of peroxynitrite may represent a potential therapeutic approach in diseases associated with the overproduction of NO and superoxide. In the present study, we tested the effect of a potent peroxynitrite decomposition catalyst in murine models of endotoxemia and sepsis. Mice were injected i.p. with LPS 40 mg/kg with or without FP15 [Fe(III) tetrakis-2-(N-triethylene glycol monomethyl ether) pyridyl porphyrin] (0.1, 0.3, 1, 3, or 10 mg/kg per hour). Mice were killed 12 h later, followed by the harvesting of samples from the lung, liver, and gut for malondialdehyde and myeloperoxidase measurements. In other subsets of animals, blood samples were obtained by cardiac puncture at 1.5, 4, and 8 h after LPS administration for cytokine (TNF-alpha, IL-1 beta, and IL-10), nitrite/nitrate, alanine aminotransferase, and blood urea nitrogen measurements. Endotoxemic animals showed an increase in survival from 25% to 80% at the FP15 doses of 0.3 and 1 mg/kg per hour. The same dose of FP15 had no effect on plasma levels of nitrite/nitrate. There was a reduction in liver and lung malondialdehyde in the endotoxemic animals pretreated with FP15, as well as in hepatic myeloperoxidase and biochemical markers of liver and kidney damage (alanine aminotransferase and blood urea nitrogen). In a bacterial model of sepsis induced by cecal ligation and puncture, FP15 treatment (0.3 mg/kg per day) significantly protected against mortality. The current data support the view that peroxynitrite is a critical factor mediating liver, gut, and lung injury in endotoxemia and septic shock: its pharmacological neutralization may be of therapeutic benefit.
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Background. Bilioduodenal (BD) and biliojejunal (BJ) derivation induce enterobiliary reflux and bile stasis. Decompression of the excluded loop of the Roux-en-Y (BJD) was proposed to minimize these effects. The aim of this study was to compare the influence of these three modalities of biliary bypass on hepatic lesion repair in rats with secondary biliary fibrosis. Materials and Methods. Rats with 15 d of biliary obstruction underwent BD, BJ, and BJD drainage and were compared with a group submitted to simulated operation (SO) and biliary obstruction (CBO). The serum values of total and fractional bilirubin, alkaline phosphatase (ALP), and aminotransferases (AST and ALT), as well as hepatobiliointestinal excretion determined with (99m)Tc-Disida, were used for comparison. In addition, we used morphometric analyses to estimate the mass of the hepatocytes, bile ducts, and liver fibrosis. We also counted hepatic stellate cells (SC). Results. For each of the three modalities of biliary drainage, there were significant reductions in bilirubin, AST, ALP, and the number of SCs. The recovery of the estimated mass of all histologic components occurred only after BJ and BJD; in the BD group, the estimated hepatocyte mass was reduced compared with the SO group. The residual hepatic radioactivity of (99m)Tc-Disida was greater in the BJD group than in the SO group. Conclusions. The interposition of the jejunal loop between the biliary tree and the intestine may slow hepatobiliary clearance of radioactivity, even though it provides the resolution of cholestasis and is effective in recovering from hepatic lesions. (C) 2011 Elsevier Inc. All rights reserved.
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Background. Ischemia-reperfusion injury is believed to be a major cause of transferred skin flap failure. Cigarette smoking is known to be associated with endogenous antioxidant depletion, hypercoagulability, and cutaneous vasoconstriction. This investigation was carried out to study possible effects of pentoxyfilline or heparin on rat skin reperfusion injury under tobacco exposure. Materials and Methods. Thirty-six rats were randomized into two major groups: 18 were exposed to cigarette smoke during a 4 wk period prior to surgery; the remaining 18 underwent a sham smoking procedure. Each group was further divided into three equal subgroups: heparin, pentoxyfilline, and saline solution. One identical skin flap was raised in each animal. The vasculature of the flap was clamped for 3 h and reperfused for 5 min. A venous blood sample was obtained from the flap after reperfusion for serum malondialdehyde (MDA) and myeloperoxidase (MPO) analysis. Flap survival was assessed 7 d after the procedure. Results. The lipid peroxidation levels and flap necrosis were significantly higher in the cigarette-smoking group skin flaps. There was also a decrease of MPO activity in this group compared with the nonsmoking group. Heparin-treated rats had significantly lower MDA levels and showed the most viable percent area among smoking rats. Conclusions. These data suggest that heparin had a significant beneficial effect both on flap survival and on the lipid peroxidation reduction after smoke exposure in the rat axial-pattern skin flap subjected to ischemia and reperfusion injury. Pharmacologic therapy may represent an alternative way to counteract tobacco effects in flap surgery in emergency situations. (C) 2010 Elsevier Inc. All rights reserved.