Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0038454 (stroke)
 147,016 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

In 30 patients with congenital or acquired heart disease the haemodynamic effects of diazepam (Valium) 0.3 mg/kg were investigated during surgical procedures under neuroleptanalgesia. The following parameters were measured or calculated: Heart rate (HR), arterial pressure (-Part, Psyst, Pdiast), pulmonary artery pressure (-PAP), right (-PRA) and left atrial pressure (-PLA), left ventricular pressure (PLV), left ventricular enddiastolic pressure (PLVED), left ventricular peak dp/dt (dp/dtmax), cardiac output (CO), cardiac index (CI), stroke volume (SV), stroke index (SI), total systemic resistance (TSR), total pulmonary resistance (TPR), work index of the right (RVWI) and left ventricle (LVWI). In comparison with a control group (n = 36) diazepam caused a decrease in arterial pressure cardiac index, stroke index, right and left atrial pressure and dp/dtmax. This, however, was mainly attributable to vasodilatation and not to a negative inotropic effect, which is of only minor importance with diazepam. These haemodynamic changes resulted in a reduction in myocardial oxygen consumption. Diazepam is a valuable drug in neuroleptanalgesia, when an increase in blood pressure can not be controlled by fentanyl or droperidol.
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PMID:[Diazepam (valium). Changes in haemodynamics, myocardial oxygen consumption and vascular tone (author's transl)]. 69 81

In 52 patients with acquired heart disease haemodynamic effects of 0,2 mg/kg and 1,0 mg/kg morphine were investigated during surgical procedures under neuroleptanalgesia. The following parameters were measured or calculated: heart rate (HR), arterial pressure (Part, Psyst, Pdiast), pulmonary artery pressure (PAP), right (PRA) and left atrial pressure (PLA), left ventricular pressure (PLV), left ventricular end-diastolic pressure (PLVED), left ventricular peak dp/dt (dp/dtmax), cardiac output (CO), cardiac index (CI), stroke volume (SV), stroke index (SI), total systemic resistance (TSR), total pulmonary resistance (TPR), work index of the right (RVWI) and left ventricle (LVWI). Myocardial oxygen consumption (EG) was calculated according to the method of Bretschneider. There was almost no change in cardiac index and stroke index. In comparison to a control group (n=36) morphine caused a dose-dependent decrease in arterial pressure and in arterial perfusion pressure during extracorporeal circulation. This, however, was mainly attributable to vasodilatation and not to a negative inotropic effect. In accordance with the changes in haemodynamics there was a remarkable decrease in myocardial oxygen consumption (EG: -21.1%; 1,0 mg/kg morphine).
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PMID:[Haemodynamic effects of morphine in man (author's transl)]. 728 4

This is the first Hungarian paper on the platelet glycoprotein IIb/IIIa (LeuPro 33) polymorphism in stroke patients. There are conflicting data about the role of this polymorphism in the pathogenesis of arterial thrombosis. The aim of our study was to describe the prevalence of PLA1/PLA2 in healthy persons and in stroke patients. From the same study population other polymorphism (prothrombin gene 20210 G/A) also has been determined. Blood sample was investigated by polymerase chain reaction in 173 unrelated healthy donors and 234 stroke patients. Stroke was documented by CT and MRI. We used a rutin questionnaire to study previous vascular events and conventional risk factors of patients. Prevalence of PLA1/PLA2 was 23.5% among healthy persons. That is higher than in other European countries (15%). It was 30.4% in stroke patients (OR: 1.42, 95%; CI: 0.87-2.31; p = 0.15). Heterozigous PLA was found in patients older than 50 by 33.6% (OR: 1.65, 95%; CI: 0.94-2.87; p = 0.09). Previous vascular events and conventional risk profil were not significantly different between PLA1/PLA1 and PLA1/PLA2 groups of patients. In patients under 50 having 20-85% stenosis of internal carotid artery there was a higher prevalence (p = 0.09). Comparing stroke patients to control population there was a slight increase (OR: 7.0; p = 0.06) in the frequency of two polymorphisms (PLA and factor II) together in the stroke cases. Polymorphism of GP IIb/IIIa LeuPro 33 seemed to be increased in stroke patients above 50 years. Carotid stenosis with polymorphism is a risk factor for young patients. PLA variant together with prothrombin gene polymorphism results very high risk for stroke.
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PMID:[Platelet glycoprotein IIb/IIIa (LeuPro 33) polymorphism in stroke patients]. 1136 63

Citicoline, an intermediate in the biosynthesis of phosphatidylcholine (PtdCho), has shown beneficial effects in various CNS injury models and neurodegenerative diseases. PtdCho hydrolysis by phospholipase A(2) (PLA(2)) after cerebral ischemia and reperfusion yields arachidonic acid (ArAc) and lyso-PtdCho. ArAc oxidative metabolism results in formation of reactive oxygen species and lipid peroxides. Lyso-PtdCho could inhibit activity of cytidine triphosphate-phosphocholine cytidylyltransferase (the rate-limiting enzyme in PtdCho biosynthesis), resulting in impaired PtdCho synthesis. Citicoline significantly increased glutathione levels and attenuated release of ArAc and the loss of PtdCho, cardiolipin, and sphingomyelin following transient cerebral ischemia. These effects could be explained by an effect of citicoline on PLA(2). Based on these observations, a mechanism has been hypothesized. This Mini-Review summarizes recent experimental data on the effects of citicoline in cerebral ischemia and evaluates several factors that might have hindered efficacy of citicoline in stroke clinical trials in the United States. Clinical stroke trials of citicoline in Europe and Japan have demonstrated beneficial effects. U.S. trials shown only marginal effects, which might be due to the 24 hr time window, the dose and route of administration, and the stringency of the primary outcome parameters. Recent evaluation of U.S. clinical data suggests that reduction of infarct growth may be a more sensitive measure of the citicoline effect than improvement on the NIH Stroke Scale (NIHSS) by > or =7 points. The citicoline neuroprotective mechanism has not been clearly identified, and its potential in stroke treatment might still be fully recognized in the United States. The clinical efficacy of citicoline should be examined further in light of the recent phase III stroke clinical trials and experimental data for cerebral ischemia.
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PMID:Citicoline mechanisms and clinical efficacy in cerebral ischemia. 1227 62

Neuroprotection by citicoline (CDP-choline) in transient cerebral ischemia has been demonstrated previously. Citicoline has undergone several Phase III clinical trials for stroke, and is being evaluated for treatment of Alzheimer's and Parkinson's diseases. Phospholipid degradation and generation of reactive oxygen species (ROS) are major factors causing neuronal injury in CNS trauma and neurodegenerative diseases. Oxidative metabolism of arachidonic acid (released by the action of phospholipases) contributes to ROS generation. We examined the effect of citicoline on phospholipase A(2) (PLA(2)) activity in relation to the attenuation of hydroxyl radical (OH.) generation after transient forebrain ischemia of gerbil. PLA(2) activity (requires mM Ca(2+)) increased significantly (P < 0.05) in both membrane (50.2 +/- 2.2 pmol/min/mg protein compared to sham 35.9 +/- 3.2) and mitochondrial fractions (77.0 +/- 1.2 pmol/min/mg protein compared to sham 33.9 +/- 1.2) after cerebral ischemia and 2 hr reperfusion in gerbil, which was significantly attenuated (P < 0.01) by citicoline (membrane, 39.9. +/- 2.2 and mitochondria, 41.9 +/- 3.2 pmol/min/mg protein). In vitro, citicoline and its components cytidine and choline had no effect on PLA(2) activity, and thus citicoline as such is not a PLA(2) inhibitor. Ischemia/reperfusion resulted in significant OH. generation (P < 0.01) and citicoline significantly (P < 0.01) attenuated their formation (expressed as 2,3-dihydroxybenzoic acid/salicylate ratio; ischemia/24 hr reperfusion, 6.30 +/- 0.23; sham, 2.56 +/- 0.27; ischemia/24 hr reperfusion + citicoline, 4.85 +/- 0.35). These results suggest that citicoline affects PLA(2) stimulation and decreases OH. generation after transient cerebral ischemia.
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PMID:Citicoline decreases phospholipase A2 stimulation and hydroxyl radical generation in transient cerebral ischemia. 1286 64

Brain phosphatidylcholine (PC) levels are regulated by a balance between synthesis and hydrolysis. Pro-inflammatory cytokines such as tumor necrosis factor-alpha (TNF-alpha) and interleukin-1 (IL-1alpha/beta) activate phospholipase A(2) (PLA(2)) and PC-phospholipase C (PC-PLC) to hydrolyze PC. PC hydrolysis by PLA(2) releases free fatty acids including arachidonic acid, and lyso-PC, an inhibitor of CTP-phosphocholine cytidylyltransferase (CCT). Arachidonic acid metabolism by cyclooxygenases/lipoxygenases is a significant source of reactive oxygen species. CDP-choline might increase the PC levels by attenuating PLA(2) stimulation and loss of CCT activity. TNF-alpha also stimulates proteolysis of CCT. TNF-alpha and IL-1beta are induced in brain ischemia and may disrupt PC homeostasis by increasing its hydrolysis (increase PLA(2) and PC-PLC activities) and inhibiting its synthesis (decrease CCT activity). The beneficial effects of CDP-choline may result by counteracting TNF-alpha and/or IL-1 mediated events, integrating cytokine biology and lipid metabolism. Re-evaluation of CDP-choline phase III stroke clinical trial data is encouraging and future trails are warranted. CDP-choline is non-xenobiotic, safe, well tolerated, and can be considered as one of the agents in multi-drug treatment of stroke.
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PMID:Cytidine 5'-diphosphocholine (CDP-choline) in stroke and other CNS disorders. 1575 28

Lipoprotein-associated phospholipase A(2) (Lp-PLA(2)), also known as platelet-activating factor acetylhydrolase, is a plasma enzyme that circulates bound to lipoproteins. The association between Lp-PLA(2) and atherosclerosis is ambiguous, as it can both degrade and generate potentially damaging vasoactive molecules. In this article, we speculate that Lp-PLA(2) associated with HDL might have cardioprotective properties, whereas the same enzyme bound to LDL might contribute directly to atherosclerosis at all stages, from lipoprotein oxidation to endothelial dysfunction, and plaque initiation and growth. Genetic and animal model studies give varying indications as to the contribution of Lp-PLA(2) to atherogenesis and tend to support the view that higher Lp-PLA(2) levels are cardioprotective. By contrast, a series of population studies point clearly to a positive association between plasma Lp-PLA(2) levels or activity levels and risk of coronary heart disease or stroke. Typically, people with Lp-PLA(2) levels in the highest quintile of the population have about a twofold greater risk than those in the lowest quintile. It is, perhaps, too early to introduce Lp-PLA(2) as a population-wide biomarker for coronary heart disease risk; however, with accumulating evidence, it might find a place in a stepwise risk assessment of individuals who require more aggressive intervention to prevent vascular disease.
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PMID:Lipoprotein-associated phospholipase A2 as a biomarker for coronary disease and stroke. 1618 51

The prevalence rates of the platelet glycoprotein IIb/IIIa Leu33Pro allele (PLA2), and factor V G1691A Leiden mutation were determined in 109 appropriate for gestational age neonates with grade I intraventricular haemorrhage (IVH) and in 118 IVH-free control infants. The PLA2 allele frequency was 16.4 % in the group of full-term infants with grade I IVH, while it was 9.5 % in the relevant controls (p < 0.005); there was no difference in the PLA allele frequencies on comparing the IVH affected (8.34 %) and unaffected (9.2 %) premature infants. By contrast, the factor V Leiden allele frequency was increased only in the subgroup of premature infants with grade I IVH as compared with the appropriate premature controls (9.25 % vs. 3.34 %, respectively, p < 0.005). These data suggest that besides the factor V Leiden mutation, the PLA2 allele, which has already been suggested to have a role in neonatal alloimmune thrombocytopenia and certain subtypes of adult stroke, can have significance in the development of the events of IVH.
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PMID:Increased prevalence of glycoprotein IIb/IIIa Leu33Pro polymorphism in term infants with grade I intracranial haemorrhage. 1677 3

The neural membranes contain phospholipids, sphingolipids, cholesterol, and proteins. Glycerophospholipids and sphingolipids are precursors for lipid mediators involved in signal transduction processes. Degradation of glycerophospholipids by phospholipase A(2) (PLA(2)) generates arachidonic acid (AA) and docosahexaenoic acids (DHA). Arachidonic acid is metabolized to eicosanoids and DHA is metabolized to docosanoids. The catabolism of glycosphingolipids generates ceramide, ceramide 1-phosphate, sphingosine, and sphingosine 1-phosphate. These metabolites modulate PLA(2) activity. Arachidonic acid, a product derived from glycerophospholipid catabolism by PLA(2), modulates sphingomyelinase (SMase), the enzyme that generates ceramide and phosphocholine. Furthermore, sphingosine 1-phosphate modulates cyclooxygenase, an enzyme responsible for eicosanoid production in brain. This suggests that an interplay and cross talk occurs between lipid mediators of glycerophospholipid and glycosphingolipid metabolism in brain tissue. This interplay between metabolites of glycerophospholipid and sphingolipid metabolism may play an important role in initiation and maintenance of oxidative stress associated with neurologic disorders as well as in neural cell proliferation, differentiation, and apoptosis. Recent studies indicate that PLA(2) and SMase inhibitors can be used as neuroprotective and anti-apoptotic agents. Development of novel inhibitors of PLA(2) and SMase may be useful for the treatment of oxidative stress, and apoptosis associated with neurologic disorders such as stroke, Alzheimer disease, Parkinson disease, and head and spinal cord injuries.
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PMID:Interactions between neural membrane glycerophospholipid and sphingolipid mediators: a recipe for neural cell survival or suicide. 1739 91

Phospholipase A(2) (E.C. 3.1.1.4, PLA(2)) plays an essential role in metabolism of membrane phospholipids, it is related to inflammatory reactions, secretion of amyloid precursor protein and activation of NMDA receptor after ischemia. In the present study we investigated PLA(2) activity in platelets from 37 Alzheimer's disease (AD) patients, 32 vascular dementia (VaD) patients and 32 individuals with ischemic stroke as compared to 27 healthy elderly controls. PLA(2) activity was determined using radiometric assay. Mean platelet PLA(2) activity was increased in individuals with Alzheimer's disease (p < 0.001). In VaD group the enzyme activity was between the values in AD and controls, these differences being significant from both groups. In the group of patients with ischemic stroke mean PLA(2) activity was higher either 48 h after the stroke or 7 days later (in both cases p < 0.001). The results may be particularly interesting in light of the fact, that inhibitors of PLA(2) activity are known.
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PMID:Platelet phospholipase A2 activity in patients with Alzheimer's disease, vascular dementia and ischemic stroke. 1744 2


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