Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:2.3.1.109 (AST)
 6,066 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Increased morbidity and mortality following transplantation surgery due to the primary nonfunction and dysfunction of the liver poses a great challenge and has increased the crescendo of research work in this field. In this study, we have tried to address the issue concerning the changes in Ca2+ homeostasis and hepatic microcirculation in 90 min of ischemia followed by reperfusion of the liver after FK506 pretreatment. Twenty dogs divided into two groups; group I (0.15 mg/kg/day FK506 for 3 days, im) and group II (control) were used for the measurement of mitochondrial (mit) and total cellular Ca2+ by atomic absorption spectrophotometer and hepatic microcirculation with laser Doppler flowmeter. Serum AST leakage was significantly (P < 0.05) suppressed in group I at 6 hr after reperfusion. The percentage gain in mit Ca2+ in group I was significantly (P < 0.05) inhibited compared to that in group II at 15 min after reperfusion and also when compared with the preischemic value it was significantly (P < 0.05) elevated at 30 min after reperfusion in group II only. FK pretreatment significantly (P < 0.05) inhibited the overload in total cellular Ca2+ at 15 and 30 min after reperfusion. Moreover, hepatic microcirculation was significantly (P < 0.001) better in group I between 2 and 6 hr after reperfusion. In conclusion, the ameliorating property of FK in ischemia-reperfusion may be explained by prevention of the cellular Ca2+ overload during the perireperfusion period.
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PMID:FK506 maintains cellular calcium homeostasis in ischemia-reperfusion injury of the canine liver. 859 5

The purpose of the study reported here was to explore a new strategy for the aerobic preservation of transplants using stable concentrated fluorocarbon emulsions as an oxygen delivery system. Fluorocarbons (FCs) are synthetic molecules, chemically and biologically inert, with a high oxygen-dissolving capacity. As they do not mix with water, it is necessary to emulsify them for intra-vascular use. Perfluorooctyl bromide (or perflubron) can be emulsifled with egg-yolk phospholipid (EYP), a nontoxic emulsifiant. The recent adjunction of amphiphilic fluorocarbon-hydrocarbon diblock molecules allows the obtaining of stable emulsions. By contrast with hemoglobin, fluorocarbons release oxygen following Henry's linear law rather than Barcroft's sigmoid curve. Release of oxygen by the FCs is only slightly influenced by temperature, which is an advantage for the preservation of organs. We tested a new 90% w/v fluorocarbon stem emulsion (perflubron/EYL/F6H10) diluted to 36% w/v with a hydroelectrolytic solution containing albumin, on four multiple organ blocks (MOBs; heart-lungs, liver, pancreas, kidneys, small intestine) of rats (EMOBs). Five control MOBs were perfused with a 50% v/v mixture of rat-blood and Krebs solution (KBMOBs). The lungs were ventilated with a FiO2 = 100%. In all cases the survival of the MOBs was greater than 210 min, with stable hemodynamics and preserved hydroelectrolytic and acid-base balances. The levels of lactate, amylase, and CK of the EMOBs were inferior (P < 0.05) to those of the KBMOBs between the first and the second hour. The diuresis of the EMOBs was higher (P < 0.05) than that of the KBMOBs (5.65 +/- 1.76 vs 1.21 +/- 0.28 mg/min). The production of bile, and the AST and ALT levels, were not significantly different. The PaO2 of the EMOBs was higher (P < 0.01) than for the KBMOBs. In normothermy, the maintenance of an aerobic metabolism using the FC emulsion caused less damage to the organs. Aerobic preservation of organs using FC emulsions therefore appears to be an attractive alternative to the presently used cold ischemia.
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PMID:Aerobic preservation of organs using a new perflubron/lecithin emulsion stabilized by molecular dowels. 866 Dec 39

We investigated whether anticoagulation would diminish ischemia-reperfusion injury of the liver. Liver ischemia was induced in rats by occluding the portal vein for 30 min. Anticoagulant was injected intravenously 10 min before occlusion. Serum concentrations of cytokine-induced neutrophil chemoattractant (CINC) in untreated rats increased following reperfusion, reaching a peak at 6 hr, then decreasing gradually to control levels by 24 hr. CINC levels in rats pretreated with heparin (50 units/kg), AT-III (250 units/kg), or DEGR-Xa (10 mg/kg) peaked at 3 hr after reperfusion and declined to baseline within 12 hr; peak CINC values were significantly lower than in untreated control rats. Expression of CINC mRNA in liver tissue paralleled the CINC serum levels. Both myeloperoxidase activity and the number of neutrophils in the liver were decreased in the anticoagulant groups. In addition, significant correlations were observed between the maximum values of AST, ALT, and LDH versus the peak CINC levels following ischemia-reperfusion. These results indicate that the release of CINC after ischemia-reperfusion of the liver is mediated by activation of coagulation within the hepatic microcirculation.
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PMID:Anticoagulant pretreatment attenuates production of cytokine-induced neutrophil chemoattractant following ischemia-reperfusion of rat liver. 868 28

Advances in liver surgery and transplantation have lead to a steady increase in the number of these interventions. Prompt quantitative assessment of hepatic of hepatic function and a patient's subsequent morbidity and mortality following surgery remain difficult despite the currently utilized historic markers of hepatic parenchymal injury (e.g., aspartate transaminase [AST], lactate dehydrogenase [LDH] gamma-glutamyl transpeptidase [GGT]). Increases in serum glycohydrolase activities appear to provide sensitive and quantitative markers of hepatic ischemia/reperfusion injury. In 10 male swine (25 to 35 kg body weight) following 30, 45, and 90 minutes of acute hepatic ischemia, the systemic release of eight different glycohydrolases and lipid peroxides into serum were determined and compared with pre- and postischemic serum levels of LDH, GGT, and AST. The rapid release of glycohydrolases into serum was directly proportional to the length of the ischemic period from 30 to 90 minutes; e.g., beta-glucosidase, mean 1.9-fold increase at 30 minutes; 8.3-fold at 45 minutes; and 22.8-fold at 90 minutes; P < .002) and the activities peaked within the first 3 hours postischemia. In constrast, AST, LDH, and GGT were released slowly and peaked 20 to 30 hours after hepatic blood flow was restored. In swine with fatal outcomes (90 minutes of ischemia), all enzyme levels increased continuously during the final hours of life. However, in swine that survived hepatic ischemia/reperfusion injury (45 minutes of ischemia) the glycohydrolases, but not AST, LDH, and GGT, declined after 2 to 3 hours' postischemia and the serum lipid peroxide levels followed the same pattern. Serum beta-galactosidase and beta-glucosidase levels are sensitive markers that rise as quickly as traditional enzyme markers (AST, LDH, GGT) following hepatic ischemic injury; moreover, the glycohydrolases have the added value of serving as predictors of survival.
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PMID:Glycohydrolases as markers of hepatic ischemia-reperfusion injury and recovery. 870 56

Eighty liver allografts were studied to determine the predictive value of intraoperative biopsies and postoperative liver function tests for the development of preservation injury (PI). Peak transaminase (aspartate transaminase [AST] and alanine transaminase [ALT]) and prothrombin time (PT) values achieved by each patient during postoperative days (POD) 1 through 7 were determined. PI in day 0 preperfusion biopsies (0Pre) (obtained immediately before implantation) and postperfusion biopsies (0Post) (obtained immediately after revascularization) was categorized by histological criteria as present or absent. PI in biopsies taken during POD 2 through 14 was histologically graded as either moderate-to-severe, mild, or absent. Of the 80 allografts, 8 were omitted because of primary nonfunction or postoperative complications. 0Pre and 0Post biopsies were available on 25 of 72 (35%) and 69 of 72 (96%) allografts, respectively. Only 2 (8%) of the 0Pre biopsies showed histological PI compared with 48 (70%) of the 0Post biopsies. Fifty-nine patients were biopsied between POD 2 through 14. Of these, 15, 28, and 16 patients developed moderate-to-severe, mild, or no evidence of PI, respectively. The presence of PI in the 0Post biopsy strongly correlated with the development of PI during POD 2 through 14 (P < .0005). Peak AST and ALT values in patients with moderate-to-severe PI on POD 2 through 14 were significantly elevated compared with those patients with either mild (P = .01 and .03) or no PI (P = .02 and .006). Because of extensive overlap in AST and ALT values between the three groups, however, transaminase values were not useful in predicting the presence or absence of PI in the individual case. The development of PI during POD 2 through 14 correlated with advanced donor age (P = .06) but was unassociated with 0Pre biopsy findings, cold ischemia time, or peak PT values. We conclude that the 0Post biopsy is a valuable tool for the prediction of subsequent PI in the early postoperative period. In contrast, 0Pre biopsy findings and peak AST and ALT values are not useful in the assessment of PI.
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PMID:Predictive value of intraoperative biopsies and liver function tests for preservation injury in orthotopic liver transplantation. 898 88

Angiotensin-converting enzyme (ACE) inhibitors have proven to be effective in the reduction of ischemia/reperfusion damage after myocardial ischemia. Whether this favorable effect can be related to other models of ischemia and reperfusion has not yet been investigated. Therefore, we studied in a model of syngeneic liver transplantation in the rat the effect of recipient enalapril treatment on postischemic liver injury. Untreated animals served as the control group. Treatment with enalapril was started 5 minutes before reperfusion by intravenous infusion of enalapril at a dosage of 5 mg/kg/h. By means of in vivo microscopy, the sinusoidal perfusion rate and leukocyte adherence in sinusoids and postsinusoidal venules were analyzed during 45 to 60 minutes of reperfusion. Liver function was monitored by measuring bile output over a period of 60 minutes. Analysis of coagulation factors (prothrombin time, factor V, fibrinogen) and liver enzymes (alanine transaminase [ALT], aspartate transaminase [AST]) served for the evaluation of organ dysfunction and damage secondary to ischemia/reperfusion injury. The sinusoidal perfusion rate was significantly improved by enalapril treatment (94.7% [1.0] vs. 75.3% [3.8]; mean [SEM]; P = .005). In addition, leukocyte-sticking in both liver sinusoids and postsinusoidal venules was remarkably reduced in enalapril-treated animals as compared with controls (stickers/lobule: 21.0 [3.3] vs. 59.2 [2.1]; P = .0004; stickers/mm2 venular surface: 20.5 [4.7] vs. 110.3 [18.1]; P = .0004). Moreover, bile output was increased (1.13 [0.35] vs. 0.43 [0.18] g bile/60 min x 100 g liver; P = .06). Values for PT (22.5% [2.1] vs. 9.7% [1.8]; P = .005), factor V 99.4% [9.5] vs. 49.5% [8.5]; P = .007), and fibrinogen (64.1% [7.7] vs. 12.8% [3.2]; P = .001) were significantly improved, paralleled by a remarkable reduction in serum ALT (1,428 U/L [190] vs. 2,315 [248]; P = .02). Our data show for the first time that ACE inhibition in the liver recipient by enalapril attenuates hepatic ischemia/reperfusion damage after experimental liver transplantation. Our results may offer a novel approach to reduce ischemia/reperfusion injury in clinical liver transplantation.
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PMID:Angiotensin-converting enzyme inhibition by enalapril: a novel approach to reduce ischemia/reperfusion damage after experimental liver transplantation. 904 13

The article presents an analysis of investigations performed for determining activity of certain enzymatic systems in the general and regional blood flow in 55 patients with the syndrome of acute ischemia of the upper and lower extremities caused by embolism and arterial thrombosis. The dynamics of fermentemia depending on the degree of ischemia and adequacy of restoration of the blood circulation in the extremity involved was established. The levels of CK, LDH, AST and ALT in the blood serum of patients with regional ischemia was shown to be of great prognostic value.
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PMID:[The dynamics of the enzyme system indices in the blood serum of patients with acute ischemia of the extremities]. 916

To evaluate the safety of temporary hepatic inflow occlusion during major liver resection, we reviewed 71 consecutive noncirrhotic patients who underwent elective liver resection using this technique. There were 27 males and 44 females (mean age, 54.4 years), the majority of whom had hepatic malignancies. There were 31 right hepatectomies, 21 left hepatectomies, and 19 extended right hepatectomies. Ischemic injury of the liver was assessed using changes in postoperative liver function tests and patient outcome was assessed using morbidity and mortality rates. After preliminary ligation of the blood supply to the lobe to be removed, global hepatic ischemia was produced by temporary occlusion of the main portal vein and hepatic artery proper while the liver parenchyma was divided. The average duration of inflow occlusion was 59 minutes (range, 25 to 90 minutes). There was no operative mortality, and no patient developed liver failure. The liver enzymes reached their peak on the first postoperative day (mean aspartate aminotransferase [AST] level, 283 +/- 227 IU/L; mean alanine aminotransferase [ALT] level, 269 +/- 238 IU/L) and they returned to normal by 7 days. The most common postoperative complications were related to the chest, wound, and urinary tract. The mean intraoperative transfusion was 3.4 +/- 2.6 U of packed red blood cells, and 0.94 +/- 2.13 U of fresh frozen plasma. We conclude that continuous hepatic inflow occlusion for periods of 1 hour during major liver resection is safe and well-tolerated when there is no underlying parenchymal liver disease.
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PMID:The safety of continuous hepatic inflow occlusion during major liver resection. 934 33

Pretransplant rinse solutions have been shown to reduce reperfusion injury in cold-stored liver grafts, especially at the nonparenchymal level in sinusoidal endothelial cells (SEC). In this study, different rinse temperatures were tested in a rat liver preservation model. Livers were washed out in situ via the portal vein with cold (4 degrees C) University of Wisconsin (UW) solution, and after hepatectomy (t0), were stored for 8, 16, or 24 h of cold ischemia time (CIT). After storage, livers were flushed with UW solution at either 4 degrees C, 20 degrees C, or 37 degrees C and reperfused for 90 min (37 degrees C). Control livers were reperfused at t0 without preflush. Levels of hyaluronic acid (HA), purine nucleoside phosphorylase (PNP), AST, and LDH were measured in the reperfusion medium. Bile production was monitored during reperfusion. At the end of reperfusion, liver biopsies were taken for enzyme hystochemistry (5'-nucleotidase and LDH). After 8-h CIT and a flush at 4 degrees C, a release of endogenous HA (-7%) was observed, whereas uptake of exogenous HA occurred after the 20 degrees C flush (2%, P = NS) and after the 37 degrees C flush (24%, p < 0.001). HA release occurred at all three preflush temperatures after the 16-h CIT but was significantly lower when flushed at 37 degrees C (-10%) that at 4 degrees C and 20 degrees C (-64% and -17%, respectively, p = 0.05). After the 24-h CIT, the release of endogenous HA increased in the 4 degrees C and 20 degrees C preflush groups, but not in the 37 degrees C group. Levels of PNP and AST increased until the 24-h CIT in all groups but were significantly lower after preflush at 37 degrees C. Release of LDH did not increase with increasing periods of cold storage in any of the flush series. Compared to control livers, mean bile production during reperfusion was significantly decreased following preflush at 4 degrees C or 37 degrees C after all periods of CIT. No differences in mean bile production could be demonstrated in the three preflush groups after any period of CIT. LDH activity in liver tissue was best preserved after the 8 and 16-h CIT in combination with the 37 degrees C preflush, indicating less hepatocellular damage. In conclusion, in cold stored rat livers flushed at 37 degrees C before reperfusion, SEC and hepatocellular damage is attenuated.
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PMID:Warm flush at 37 degrees C following cold storage attenuates reperfusion injury in preserved rat livers. 950 53

In situ splitting of cadaver livers has been reported to reduce cold ischemic damage, to avoid biliary complications, and to result in improved graft survival. In this study, which involved a wider application of split liver transplantation (SLT), we examined the effects of a technique combining both ex situ and in situ splittings in triple SLT in pigs and compared it to ex situ splitting alone. In the combination splitting group, the splitting between the right and left lobes was done in situ with perfusion of the left lobe with cold, lactated Ringer's solution; that between the lateral and medical right lobes was done ex situ in backtable surgery. The time required for in situ splitting was 28 +/- 5 min. The time for backtable surgery and the total ischemia time were significantly shorter in the combination splitting group than that in the ex situ splitting group (P < 0.05). One day after triple SLT, the elevations in both serum AST and LDH in the ex situ splitting group were significantly greater than those in the combination splitting group (P < 0.05). We conclude that combination splitting may provide a technical improvement and have a beneficial effect on the clinical application of triple SLT.
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PMID:Combination splitting using both in situ and ex situ techniques in triple split liver transplantation in pigs. 987 Feb 68


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