Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound   Target Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound

---

Query: EC:2.6.1.1 (aspartate aminotransferase)
21,665 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

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.
...
PMID:Warm flush at 37 degrees C following cold storage attenuates reperfusion injury in preserved rat livers. 950 53

Continuous warm blood cardioplegia was widely used, as an effective means of myocardial preservation, in open heart surgery. The comparisons of myocardial protective effects between traditional cold crystalloid and warm blood cardioplegia, however, have been based mainly on hemodynamics, cardiac function and myocardial metabolism, other than clinical outcome. The present study was designed to examine myocardial protective effects by assessing clinical outcome, enzyme levels and myocardial cytochemistry. Twenty patients undergoing heart valve replacement were divided randomly into two groups: Group I was given intermittent perfusion of cold crystalloid (St. Thomas Hospital solution) with hypothermic cardiopulmonary bypass (CPB) and Group II was given continuous administration of warm blood cardioplegia with normothermic CPB. The groups were similar with respect to sex, age, body surface area and preoperative ventricular function. Blood samples were obtained from an indwelling radial arterial catheter or from the arterial end of the oxygenator. Biopsy specimens from the right atrium were obtained immediately before aortic declamping (ischemic period) and 30 minutes after crossclamp removal (reperfusion period). Serum enzymes, including alanine transaminase (ALT), aspartate aminotransferase (AST), lactate dehydrogenase (LDH) and its isoenzymes and creatine phosphokinase (CK) and its isoenzyme, were determined. Myocardial cytochemistry were chiefly assessed by grey-scale image processing of adenosine triphosphatase (ATPase), succinate dehydrogenase (SDH) and cytochrome oxidase (CCO) examinations. Relations among the results were discussed. Reperfusion time was reduced and ventilation support time decreased in Group II (33.50 +/- 3.78 min vs. 25.00 +/- 4.46 min, p < 0.05; 38.98 +/- 16.55 h vs. 19.84 +/- 1.11 h, p < 0.05). Rates of atrial beating during aortic crossclamp and spontaneous recovery to normal sinus rhythm were much higher in Group II than in Group I (80% vs. 20%, p < 0.05; 70% vs. 10%, p < 0.05). Differences in hospital morbidity and mortality between groups were nonsignificant. Serum AST, ALT, LDH and LDH1 + LDH2 all showed no significant intergroup differences. There was a higher serum CK-MB level with a delayed peak in Group II. The cytochemistry activities of ATPase was not different between groups and periods and SDH was the highest during reperfusion period in Group I and of CCO significantly much promoted in Group II in both periods. Continuous warm blood cardioplegia resulted in higher spontaneous recovery to sinus rhythm, shorter reperfusion and ventilation support time. Damage to the myocardium, skeletal muscle and liver always occur in warm blood cardioplegic patients. However, warm blood cardioplegia is still a practical method for myocardial preservation in open heart surgery.
...
PMID:A generalized consideration of myocardial preservation with cold crystalloid versus warm blood cardioplegia in heart valve replacement. 961 11

The isolated perfused rat liver model was used to assess graft viability after 24 h of cold preservation. Two solutions were compared for liver preservation: Belzer's original UW solution (high-K+ UW) and a solution containing the same components but with inverted concentrations of sodium and potassium (high-Na+ UW). During the 120 min of normothermic reperfusion, livers preserved in the high-Na+ UW solution released lower levels of creatine kinase-BB isoenzyme, transaminases (ALT and AST), and potassium than those preserved in the high-K+ UW solution. Bile flow and biliary excretion of indocyanine green increased when livers were preserved in the high-Na+ UW solution. We found no statistical differences for oxygen consumption and tissue ATP concentration. The results of this study support the concept that a high-Na+ UW solution is a more effective means of preserving rat livers, at least after 24 h of cold-storage and 120 min of reperfusion in the isolated perfused model, than the original high-K+ UW solution. Liver preservation in the high-Na+ UW solution reduces damage to sinusoidal endothelial and hepatocellular cells. The use of an extracellular-like Belzer cold storage solution eliminates potassium-related problems in cold preservation and subsequent normothermic reperfusion while keeping all the qualities of the original UW solution.
...
PMID:High-Na+ low-K+ UW cold storage solution reduces reperfusion injuries of the rat liver graft. 963 53

Liver transplantation (Ltx) has become a routine procedure for patients with end-stage liver disease. Despite ongoing progress on short- and long-term graft survival, primary dysfunction (PDF) remains a major problem. PDF is significantly associated with the duration of cold ischemia- and, possibly, with reperfusion-related injury. Nitric oxide (NO) has many physiological functions and plays an important role in modulating tissue injury. However, the mechanism of NO action in ischemia/reperfusion injury after Ltx is thus far unknown. In this study we investigated the role of inducable NO synthase (iNOS) in the liver after preservation with UW solution using the orthotopic Ltx model in the rat. Male Brown Norway rats were used for the Ltx procedure. After donor hepatectomy, livers were stored on ice-cold UW solution for 24 or 40 h and subsequently transplanted. A control group consisted of rats with Ltx after less than 1 h storage. Post-transplant blood samples were taken at 48 h to determine standard parameters for liver injury (aspartate transaminase, lactate dehydrogenase). Liver biopsies were obtained for detection of expression of iNOS (western blot) 24 and 48 h post-transplant. We observed that a preservation time of 24 h in UW solution presents no problem for graft survival after Ltx in rats with some brain function and in healthy animals. After 40 h preservation, liver damage is obvious and graft survival reduced, indicating the limits of cold storage may be within reach. With longer preservation times, more NOs was detected in liver tissue. This finding suggests that NO has a role in ischemia/reperfusion-related injury. Current intervention with NOS inhibitors will reveal whether NO has a negative or a positive effect on graft survival after Ltx.
...
PMID:Extended preservation and effect of nitric oxide production in liver transplantation. 966 72

Hepatic allograft rejection remains an important problem following liver transplantation, and, indeed, complications related to the administration of immunosuppressive therapy remain a predominant cause of posttransplantation morbidity and mortality. The Liver Transplantation Database (LTD) was used to study a cohort of 762 consecutive adult liver transplantation recipients and determined the incidence, timing, and risk factors for acute rejection. We also evaluated the impact of histological severity of rejection on the need for additional immunosuppressive therapy and on patient and graft survival. Four hundred ninety (64%) of the 762 adult liver transplantation recipients developed at least one episode of rejection during a median follow-up period of 1,042 days (range, 336-1,896 days), most of which occurred during the first 6 weeks after transplantation. Multivariate analysis revealed that recipient age, serum creatinine, aspartate transaminase (AST) level, presence of edema, donor/recipient HLA-DR mismatch, cold ischemic time, and donor age were independently associated with the time to acute rejection. An interesting observation was that the histological severity of rejection was an important prognosticator: the use of antilymphocyte preparations was higher, and the time to death or retransplantation was shorter, for patients with severe rejection. Findings from this study will assist in decision-making for the use of immunosuppressive regimens and call into question whether complete elimination of all rejection or alloreactivity is a desirable goal in liver transplantation.
...
PMID:Acute hepatic allograft rejection: incidence, risk factors, and impact on outcome. 973 52

Intracellular-type electrolyte solutions were introduced into organ preservation to prevent K+ efflux and Na+ and Cl- influx into cells and cell swelling during cold ischemia. We studied cation accumulation in the interstitial space by microdialysis, during rat liver cold storage and after flush-out with high-K+ and low-K+ solutions. The effect of Na+ and K+ on graft function and survival was studied in an isolated perfused liver model and an orthotopic transplantation model after rat liver storage in iso-osmolar high-K+ and low-K+ solutions. After 24 hours of cold ischemia [Na+]o dropped from 136 +/- 2 mmol/L to 91.8 +/- 1.1 mmol/L, and [K+]o increased from 5.9 +/- 0.1 mmol/L to 12.2 +/- 1.6 mmol/L (P < .001 vs. control). [Na+]o and [K+]o after flush-out did not equilibrate with [Na+]sol and [K+]sol after 24 hours of cold storage. Rat livers preserved in low-K+ solutions produced significantly more bile during isolated reperfusion and released less alanine transaminase, aspartate transaminase, and lactate dehydrogenase into the reperfusion medium than high-K+ solutions. Rat liver survival after 14 hours of preservation was higher in low-K+ solutions (13 of 13) than in high-K+ solutions (7 of 13). Those studies indicate that during cold storage of rat livers, transmembraneous Na+-K+ sodium-potassium exchange might not follow the 3:2 stochiometry of a sole sodium-potassium exchange via Na+-K+ sodium-potassium adenosine triphosphatase (ATPase), and that low-K+ solutions might improve graft function and survival after rat liver preservation.
...
PMID:Interstitial accumulation of Na+ and K+ during flush-out and cold storage of rat livers: implications for graft survival. 979 18

The purpose of this paper was to assess the role of continuous warm blood cardioplegia in heart valve replacement in comparison with standard intermittent cold crystalloid cardioplegia. Twenty patients undergoing open heart valve replacement were divided arbitrarily into two groups in this study; Group I was given intermittent perfusion of cold crystalloid (St. Thomas Hospital solution) with hypothermic cardiopulmonary bypass (CPB) (10 patients) and Group II was given continuous administration of warm blood cardioplegia with normothermic CPB (10 patients). The groups were similar with respect to sex, age, body surface area and preoperative ventricular function. Bypass conditions as well as perioperative complications were evaluated in the respective groups. Peak values of the serum enzyme levels within 120 hours of postoperation including alanine transaminase, aspartate aminotransferase, lactate dehydrogenase (LDH) and its isoenzymes LDH1 + LDH2, phosphokinase (CK) and its isoenzyme CK-MB, superoxide dismutase, and malondialdehyde in the two groups were also assessed. Biopsies from the right atrium were obtained immediately before aortic cross clamp removal (ischemic period), and 30 minutes after cross clamp removal (reperfusion period). Myocardial structures were observed and scored. No significant intergroup differences were found in the bypass conditions except for the perfusion flow, systemic temperature and central venous pressure. There were no significant differences in the intergroup perioperative complications, either. Serum enzymes except CK which reached peak values in Group I appeared prior to or consistent with Group II. There were no significant intergroup differences in peak levels of the serum enzymes except CK (307.44 +/- 38.56 U/L vs. 466.29 +/- 52.03 U/L, p = 0.039 for CK). From the pathological assessment, the structural alterations were the most severe during the reperfusion period in group I. Myocardial damage showed more severely in reperfusion than in ischemia in both. Warm blood cardioplegic technique, raising potential hazards, is still a practical method for myocardial protection in open heart surgery, but might be less effective in protecting the tissues beyond myocardium.
...
PMID:Benefits and pitfalls of warm blood cardioplegia in heart valve replacement: systemic protective effects. 981 3

In this study we investigated the effect of calcium addition to the UW solution on the quality of the preserved rat liver as judged by normothermic isolated perfusion. Rat livers were cold stored in UW solution containing varying concentrations of calcium chloride (0, 0.5, 1.5, 5.0 mM) for periods of 0, 24 and 48 hours. At the end of the preservation period the livers were reperfused for 90 minutes at 37 degrees C with Krebs Henseleit Buffer. The quality of preservation was assessed by quantification of enzyme release, bile production and protein synthesis. The addition of 1.5 mM calcium to the UW solution suppressed the incidence of damage in the 24 hour cold stored liver similar to control livers (0 hours preserved). LDH release were significantly reduced from 22.1 +/- 7.3 (units/hr/g) in regular UW to 9.4 +/- 0.8 (units/hr/g) in UW plus 1.5 mM calcium. AST release also was suppressed by the addition of calcium to the UW. Bile production was enhanced by the addition of calcium; from 21.3 +/- 0.6 (mg/hr/g) in regular UW to 46.3 +/- 5.9 (mg/hr/g) in UW plus 1.5 mM calcium. Protein synthesis was reduced to 38% of control after 24 hr cold storage and was unchanged by the addition of calcium to the preservation solution. Although the addition of calcium to the UW solution improved the preservation of the 24 hour cold stored liver it did not offer the same degree of protection to the 48 hour preserved liver. Therefore, calcium addition may be one agent for improving preservation for short term cold storage of the liver but longer term storage will require other modifications as well.
...
PMID:The effect of calcium in the UW solution on preservation of the rat liver. 986 39

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.
...
PMID:Combination splitting using both in situ and ex situ techniques in triple split liver transplantation in pigs. 987 Feb 68

We investigated the protective effect of urinary trypsin inhibitor (ulinastatin: UTI) in vitro, in relation to the neutrophil activity in hepatic ischemia/reperfusion (I/R) injury. The rat liver was removed and preserved in cold Ringer's lactate solution for 60 min, followed by 120 min of reperfusion with oxygenated perfusate. The rats were divided into four groups (n = 8 in each group). The livers were perfused with Krebs-Henseleit (K-H) solution containing no additives in group 1, 50,000 U/kg of UTI in group 2, 3.5 x 10(6) of neutrophils in group 3, and both neutrophils and UTI in group 4. In group 3, the AST and ALT levels were always higher than those in other three groups at any point evaluated (P < 0.01) and the LDH levels were observed to be significantly higher than those in other three groups at 0, 5, 10, 60, and 90 min after reperfusion (P < 0. 01). These increase were suppressed by additional pretreatment with UTI in group 4. The bile flow during reperfusion was significantly suppressed in group 3 compared to that of group 4, at both 30 (P < 0. 01) and 60 (P < 0.05) min after reperfusion. The MPO activity after reperfusion in group 3 also significantly increased compared to other three groups (P < 0.01). These data thus suggest that UTI ameliorated the ischemia/reperfusion injury in vitro by inhibiting of neutrophil accumulation in the postischemic liver.
...
PMID:Protective effects of ulinastatin against ischemia-reperfusion injury. 1006 23


<< Previous 1 2 3 4 5 6 7 8 9 10 Next >>

---