Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0022116 (ischemia)
 91,303 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

This study identifies the major risk factors associated with outcome after liver transplantation, showing that candidates for this surgery can be stratified into differential risk categories at the time of the actual surgery. All the livers used were flushed with University of Wisconsin solution. The study is a retrospective multivariate analysis of 2376 consecutive transplantations performed on 2019 recipients between November 1, 1987, and December 31, 1993. Donor variables studied were age, sex, blood type, cause of death, intensive care unit length of stay, body mass index, use of pressors (dopamine infusion > 10 micrograms/kg/min or continuous infusion of epinephrine or norepinephrine), use of pitressin, cardiopulmonary resuscitation, terminal transaminase levels, serum sodium level at procurement, and total ischemia time. Recipient variables studied were age; sex; blood type; indication for liver transplantation; history of liver transplantation or upper abdominal surgery; United Network for Organ Sharing urgency status; need for mechanical ventilation; primary immunosuppression; and preoperative bilirubin level, prothrombin time, and creatinine level. The variables independently associated with outcome were donor age, female donor sex, ischemia time, recipient age, prior liver transplant, preoperative mechanical ventilation, preoperative bilirubin level, preoperative creatine level, indication for transplantation and primary immunosuppression used. The results of this study not only give us insight into the probable outcomes of individual patients, but also show that this stratification can be useful when comparing results across different groups or in helping to choose the best donor-recipient combination based on the calculated probability of a favorable outcome.
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PMID:Matching donors and recipients. 974 4

The HELLP syndrome is a dangerously severe form of preeclampsia associated with multiorgan system damage and occurs in 0.2-0.6% of all pregnancies. It usually presents with abdominal pain, often in the setting of preeclampsia. In most cases, HELLP is initiated by inadequate placental vessel development with subsequent placental ischemia, leading to the release of circulating vasoconstrictors. These powerful vasoconstrictors include thromboxane A2, angiotensin, prostaglandin F2, and endothelin-1. The ischemic placenta also produces fewer vasodilators, such as prostacyclin, prostaglandin, E2, and nitric oxide. The ensuing imbalance in vasoactive substances causes intense systemic vasospasm and multiorgan endothelial damage. Multiple genetic, coagulation, and immunologic disorders also appear to contribute to the endothelial damage. Fibrin and platelets are then deposited on the endothelial surfaces leading to the hemolytic anemia, elevated liver enzymes, and low platelets of the HELLP syndrome. The most reliable laboratory tests for the diagnosis of HELLP are a complete blood count with peripheral smear, lactate dehydrogenase, serum transaminases, and urinalysis. Supportive tests include serum haptoglobin, D-dimer fragment levels, lactate dehydrogenase isoenzymes, total bilirubin, prothrombin times, and activated partial thromboplastin times. Lactate dehydrogenase and the platelet count are the two best tests to monitor the course of the disease. Prompt delivery is the treatment of choice. The intensity of the HELLP syndrome peaks 24 hours after delivery. Extended atypical HELLP has been successfully treated with plasma exchange. The clinical laboratory professional plays an important role in the diagnosis, follow-up, and treatment of patients with the HELLP syndrome.
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PMID:HELLP! A cry for laboratory assistance: a comprehensive review of the HELLP syndrome highlighting the role of the laboratory. 984 23

To evaluate the involvement of tissue factor (TF) in blood coagulation reflecting injury of the blood vessels induced by reperfusion following ischemic treatment in rat abdominal blood vessels in vivo, both TF expression and prothrombin time (PTT), which is used as a marker of coagulation, were measured after ischemic-reperfusion treatment. TF expression was significantly increased at 0 and 5 min after reperfusion following a 30 min period of vessel ligation, while the PTT was significantly shortened at 5 and 10 min. On the other hand, the change of TF expression and PTT were not detected in the animals ligated vessel for 15 min. These results suggest that TF plays an important role in the injury after reperfusion following ischemia.
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PMID:Enhancement of tissue factor following ischemic-reperfusion injury in rats. 1010 May 7

In this study, we evaluated the role of proteolytic enzymes belonging to the coagulation, fibrinolytic, and plasma contact systems in the early postoperative phase after orthotopic liver transplantation (OLT). Twenty-nine patients were studied at the time of OLT and during the first 2 postoperative weeks. Blood samples were collected daily after OLT and analyzed for kallikrein-like activity (KK), functional kallikrein inhibition (KKI), plasmin-like activity (PL), and alpha2-antiplasmin (AP). In addition, prekallikrein (PKK), prothrombin (PTH), antithrombin III (AT III), plasminogen (PLG), prothrombin/antithrombin III complexes (TAT), prothrombin fragment 1 + 2 (F1 + 2), and plasmin/alpha2-antiplasmin complexes (PAP) were measured. Nineteen patients experienced biopsy-verified acute rejections (AR) and ten patients had uneventful courses and served as controls. Plasma analyses showed that the contact, coagulation, and fibrinolytic systems were activated during OLT. Following OLT, continuous thrombin and plasmin generation was observed, and these effects were more pronounced in the group having an uneventful course than in patients with AR. Factors that could possibly affect plasma proteolytic activity, such as blood product usage during and after OLT and cold ischemia time of the liver graft, did not differ between the groups, nor did the routine liver function tests, alanine aminotransferase (ALT) and aspartate aminotransferase (AST).
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PMID:Plasma proteolytic activity in liver transplant rejection. 1036 91

Serum levels of the actin scavenger Gc-globulin (group-specific component, vitamin D-binding protein), a member of the albumin multigene family, are decreased in severe liver disease but have not been evaluated in relation to liver transplantation. We measured Gc-globulin and Gc-globulin-actin complex ratio daily for 2 weeks after transplantation in 17 patients with end-stage liver disease. Before transplantation, Gc-globulin levels were significantly less in the patients than in healthy controls (235 +/- 106 v 340 +/- 35 mg/L, respectively; P<.001), whereas complex ratio level was in the normal range. Five patients (group N) had pretransplantation Gc-globulin values within the normal range (mean +/- 2 SD), and 12 patients had subnormal values (group S). In group N, mean Gc-globulin levels posttransplantation remained stable at a lower level than before transplantation but still within normal range. In this group, cold ischemia time correlated inversely with Gc-globulin levels on day 2 (r = -0.88; P <.05). In group S, normal mean levels were reached at a mean of 11 days after transplantation. However, almost half these patients had subnormal Gc-globulin levels at day 14. Complex ratio levels remained normal in the study period in both groups. Prothrombin index levels (plasma coagulation factors II, VII, and X) were identical in both groups and returned to normal 7 days posttransplantation, whereas plasma albumin levels were less than normal in both groups and further decreased after transplantation. In conclusion, the maintenance (group N) or reestablishment (group S) of serum Gc-globulin to normal levels occurred in the early posttransplantation course in the same time frame as the prothrombin index. Gc-globulin synthesis seems unrelated to albumin synthesis. A prolonged cold ischemia time may cause reduced Gc-globulin levels early after transplantation.
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PMID:Reconstitution of the actin-scavenger system after orthotopic liver transplantation for end-stage liver disease: a prospective and longitudinal study. 1038 4

Prothrombin gene G20210A polymorphism has been recently identified as a cause of venous thrombosis. However the association between this mutation and arterial thrombosis remains uncertain. Some authors have suggested that the polymorphism in the 3' region of the prothrombin gene may precipitate cerebral arterial thrombosis in young patients with prothrombotic conditions. We report a case of post-traumatic basilar artery thrombosis in a young patient carrier of the prothrombin gene G20210A polymorphism. Thirty-six hours after sustaining a head injury in the occipital region, a young man developed vomiting, headache, dizziness and truncal ataxia, without signs of focal impairment. Magnetic resonance imaging and selective angiography carried out 2 days later showed an obstruction of the basilar artery, with infarction of the right cerebellar region. A transthoracic echocardiogram showed a patent foramen ovale with little left-to-right shunt and an aneurysm of the interatrial septum. Blood examination showed a heterozygous status for prothrombin gene G20210A polymorphism. We conclude that this prothrombin gene mutation and the coexisting particular head injury and interatrial septal aneurysm could have contributed simultaneously to the development of basilar artery occlusion and cerebellar infarction. We suggest that in selected cases of cerebellar ischemia a prothrombin gene G20210A polymorphism should be considered.
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PMID:Post-traumatic basilar artery thrombosis in a young man with atrial septum aneurysm and prothrombin gene G20210A polymorphism. 1049 21

Primary cases of splanchnic vein thrombosis are now less common since a systematic screening for hypercoagulability is performed. In 1996, a sequence variation in the 3'-untranslated region of the prothrombin gene (F.II 20210G/A mutation) has been linked to a threefold increased risk for venous thrombosis. The role of this thrombophilic disorder is not documented in patients with thrombosis of the splanchnic veins. This report presents two patients with a mesenteric ischemia associated with a heterozygous state for the F.II 20210G/A mutation. The first patient developed an ischemic colitis and the second one an ischemic necrosis of the terminal ileum related to a thrombosis of the superior mesenteric vein. In both cases, another thrombotic risk factor was associated: either a general prothrombic state (primary antiphospholipid syndrome) or a focal factor (abnormal hemodynamic conditions related to a liver cirrhosis). It has recently been proposed that several conditions need to be combined for deep vein thrombosis to develop. Screening for the combination of multiple underlying prothrombotic conditions thus appears justified in patients with splanchnic thrombosis. The role of the F.II 20210G/A mutation as a predisposing factor for thrombosis of the digestive vessels should be considered and needs further investigation.
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PMID:Prothrombin 20210G/A mutation in two patients with mesenteric ischemia. 1050 34

Thrombin activity has been implicated as a mechanism for failed reperfusion and reocclusion following thrombolysis. Aggregating platelets provide a phospholipid surface on which prothrombin is cleaved to form thrombin. We examined markers of thrombin generation and activity in patients enrolled in a randomized, placebo-controlled, dose escalating trial of the platelet glycoprotein IIb-IIIa inhibitor eptifibatide (Integrilintrade mark) administered concomitantly with tissue plasminogen activator for the treatment of myocardial infarction. Measurements were obtained at baseline, at 90 minutes, and at 6, 12, and 24 hours after starting therapy. Eptifibatide inhibited platelet aggregation in response to 20 microM ADP. Levels of fibrinopeptide A (FPA), thrombin-antithrombin complexes (TAT), and prothrombin fragment 1.2 (F1.2) were not lower in patients treated with eptifibatide than in the control group. In the course of dose escalation, two groups of patients received the same 135 microg/kg bolus of eptifibatide, one with and one without a heparin bolus. FPA levels were dramatically lower in the heparin-treated patients. Levels of FPA, TAT, and F1.2 were not higher in patients with than in those without recurrent ischemia, or in patients without than in those with Thrombolysis in Myocardial Infarction (TIMI) grade 3 angiographic flow at 90 minutes. These data suggest that thrombin generation and activity persist following thrombolysis, despite inhibition of platelet aggregation, and that treatment with inhibitors of thrombin activity may be required even when glycoprotein IIb-IIIa inhibitors are used.
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PMID:Inhibition of platelet aggregation with a glycoprotein IIb-IIIa antagonist does not prevent thrombin generation in patients undergoing thrombolysis for acute myocardial infarction. 1059 Jan 83

Sudden infant death syndrome or "cot death" has until the late eighties been a significant cause of death in children between the ages of 1 month and 1 year. Approximately two per 1000 children born alive dies of sudden infant death syndrome each year in Western Europe, North America, and Australia. The vulnerability of the infant brain stem to ischemia has been suggested to be a conceivable cause of sudden infant death syndrome. This is compatible with a hypothesis that genetic risk factors for cerebral thrombosis could cause microinfarction in the brain stem during the first month of life, affecting vital centers or their blood supply. The presence of three common point mutations seen in families with thrombophilia (1691G-->A in the coagulation factor V gene, 677C-->T in the methylenetetrahydrofolate reductase gene, and the 20210G-->A mutation in the prothrombin gene) could increase the risk for thrombosis in the child. This prompted us to investigate these genetic markers of thromboembolic disease in 121 cases of sudden infant death syndrome and in relevant controls, in the expectation of a more frequent occurrence of these markers if thrombosis is an etiological factor in sudden infant death syndrome. The frequency of homozygous 1691G-->A mutation in SIDS cases was higher than expected (odds ratio: 7.3, 95% confidence interval, 1.2-45.8). The allele frequencies (theta;) in cases of sudden infant death syndrome of the 1691G-->A, 677C-->T, and 20210G-->A alleles was 2.6% (1.0-5.5), 32.6% (26.8-38.9), and 0.9% (0.1-3.4), respectively. None of the allele frequencies found in the background population (3.4% for the 1691G-->A allele, 29% for the 677C-->T allele, and 1% for the 20210G-->A allele) differed significantly from that in cases of sudden infant death syndrome. In 5,251,027 inhabitants in Denmark, the incidence of venous thromboembolism was 0.9 per 1000 per year in the background population, and less than one-thousandth of these were children. Consequently it is not likely that venous thrombosis is a major cause of sudden infant death syndrome. On the other hand, this does not exclude other known or unknown risk factors for thrombosis as possible etiological factors for sudden infant death syndrome. It is likely that we must continuously employ the exclusion principle on possible etiological causes in genetic material from a large group of victims of sudden infant death syndrome if the phenomenon of sudden infant death syndrome is to be ascribed to a specific hereditary disorder.
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PMID:Sudden infant death syndrome, childhood thrombosis, and presence of genetic risk factors for thrombosis. 1082 69

The most recently characterized genetic defect contributing to venous thrombophilia is the 20210 A prothrombin gene mutation. We describe a patient with this defect who had arterial thrombosis resulting in considerable mesenteric ischemia. Several environmental factors, which might otherwise be considered of low thrombotic risk, may also have contributed to her condition. The recognition of the potential for novel presentations of hypercoagulable states may contribute to a reduction in the morbidity associated with acute mesenteric ischemia.
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PMID:Multiple arterial thromboembolisms in a patient with the 20210 A prothrombin gene mutation. 1084 73


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