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)

Hydroxyethyl starch (HES) is often used for volume therapy. Since bleeding complications have been reported repeatedly, a strict dose limitation of a maximum of 1,500 ml 6% solution per day is recommended. However, many indications require higher dosages. Bleeding complications are known to be caused by an acquired von Willebrand syndrome. It has been shown that the accumulation of large molecules and their impairment in the coagulation system can be avoided by using HES preparations with a low in vivo molecular weight. However, the effects of a high-dose therapy have not been studied yet. We have investigated, how a 4-day high-dose therapy, using 3,000 ml 6% HES 70/0.5 on the 1st day and 1,500 ml on days 2-4, affects the coagulation system and hemorheological parameters of acute stroke patients. Thromboplastin time, activated partial thromboplastin time and thrombin time showed no significant changes, except for a slight, clinically irrelevant change due to dilution. The subunits of von Willebrand factor VIII showed no significant change. Hematocrit decreased from 42.3 +/- 4.6 to 37.4 +/- 3.9% (p < 0.05) after day 1, reaching 35.3 +/- 4.2% (p < 0.01) at the end of the therapy, demonstrating a substantial volume effect. Plasma viscosity and erythrocyte aggregation decreased slightly, however not significantly. Our study shows that even a high-dose therapy with 6% HES 70/0.5 has no influence on the coagulation system.
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PMID:No coagulation disorders under high-dose volume therapy with low-molecular-weight hydroxyethyl starch. 969 Apr 84

An increased incidence of cerebral thromboembolic events has been reported in young patients with inflammatory bowel disease (IBD). It has been suggested that a hypercoagulable state is associated with clinical activity of the disease, with elevation of factors V, VIII, fibrinogen and platelets and a lowering of anti-thrombin III. We present the case of a 35 y/o male with refractory Crohn's disease who complained of headaches, blurred vision and tonic-clonic seizures. The studies demonstrated an ischemic stroke of the left cerebral hemisphere, without vascular abnormalities. Elevation of factor VIII, platelets, and antithrombin III were found. The symptoms were relieved with medical treatment and the patient has continued in good health after resection of the diseased terminal ileum.
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PMID:Cerebral thrombosis associated with active Crohn's disease. 988 77

The room tilt illusion is a transient misperception of the visual image as tilted on its side or even upside down; in this case it has been termed acute upside down reversal of vision. We report on two cases of room tilt illusion as manifestation of VIII nerve neuritis (herpes-zoster infection) and cerebellar hemorrhage. Room tilt illusion has been reported in association with vertebrobasilar stroke, migraine, multiple sclerosis, epilepsy and labyrinthine disorders. The pathophysiology of this rare visual illusion has been related to a lesion of the visual or vestibulo-otolith pathways. In animals the neurones of the parieto-insular vestibular cortex areas are multisensory. So, they can respond to somatosensory, optokinetic and visual stimuli. In humans the knowledge about vestibular cortex function and localization is less precise than in animals. However, we propose a disorder of multisensorial vestibular cortex, resulting from a lession of vestibular pathways or association cortex, as mechanism of this phenomenon.
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PMID:[Room tilt illusion: Report of two cases and terminological review]. 2116 31

Historically, the leading cause of death among persons with haemophilia and other congenital coagulation disorders was uncontrolled bleeding. Mortality was associated with severe deficiency of coagulation factors VIII or IX and especially with high-titre antifactor neutralizing antibodies (inhibitors). The catastrophic contamination of plasma donor pools with human immunodeficiency virus (HIV) resulted in acquired immunodeficiency syndrome replacing haemorrhage as the leading cause of death among persons with haemophilia. Rather little has been written, however, about mortality among those not infected with HIV. The objective of this study was to identify conditions associated with all-cause mortality among HIV-uninfected patients who were followed for a mean of 8.8 years in the Multicentre Hemophilia Cohort Study. Among the 364 children (mean age 8 years), there were four deaths; two related to cancer, one to trauma, and the fourth to haemorrhage, end-stage liver disease and sepsis. Among the 387 HIV-uninfected adults (mean age 35 years) there were 29 deaths, with haemorrhage the leading cause of death, followed by hepatic, stroke and cancer deaths. Prognostic factors for all-cause mortality among the adults included haemophilia Type A with neutralizing antibodies [age-adjusted relative rate (RR) 3.1, 95% confidence interval (CI) 1.4-6.9] and serologic evidence of both hepatitis B and C virus (RR 4.1, 95% CI 0.97-17.6). Although hepatitis C viral load was slightly lower in patients with hepatitis B virus surface antigenaemia, it was unrelated to vital status. We conclude that causes of death and prognostic factors for current HIV-uninfected haemophilia patients are similar to those noted before the HIV epidemic. Better understanding, prevention and control of neutralizing antibodies and hepatitis infections may substantially improve longevity for people with haemophilia.
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PMID:Factors predictive of death among HIV-uninfected persons with haemophilia and other congenital coagulation disorders. 1219 76

Hypertension is the most common medical complication of pregnancy in South Africa and a major cause of maternal and perinatal morbidity and mortality worldwide. At King Edward VIII Hospital in Durban, 18% of all admissions to the obstetric unit have some degree of high blood pressure. Hypertension in its most severe form produces convulsions, proteinuria, and edema and may lead to fetal and maternal death. High-risk groups for preeclampsia are teenage mothers, primigravidas, and women with a history of elevated blood pressure, previous preeclampsia, molar pregnancies, multiple pregnancies, or hydrops fetalis. Methods used to prevent preeclampsia include a low-salt diet supplemented with calcium, magnesium, zinc, fish, and pharmacological manipulation. In developing countries, prevention and detection of preeclampsia is difficult since women seek antenatal care late in their pregnancies. In Durban, the average gestational age at first antenatal attendance is 28 weeks, and 80% of patients presenting with eclampsia have defaulted antenatal care. Treatment includes admission to hospital to establish the etiology of the hypertension and maternal renal function tests . Fetal condition is a sensitive index of hypertension and is judged by 1) clinical evidence of fetal growth, 2) weekly antepartum cardiotocography, and 3) ultrasonographic screening. Patients are managed according to three clinical groups: 1) those identified before 36 weeks, 2) those identified after 36 weeks, and 3) patients in hypertensive crisis. Dihydralazine is the drug of choice for imminent eclampsia. If the patients has a ripe cervix, delivery is induced with 6-8 hours. Steroid contraception use in the older hypertensive patient should be avoided because of possible development of atherosclerosis and stroke. Puerperal tubal ligations in the hypertensive patient ought to be avoided because of the risks of thromboembolic phenomena and pulmonary embolism. Methyldopa is the treatment of choice in cases of moderate to severe hypertension. Intravenous dihydralazine is relatively safe for the rapid reduction of high blood pressure.
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PMID:Coping with hypertension in pregnancy. 1234 38

This article discusses evidence for the role of pharmacological interventions such as the protease inhibitor aprotinin (Trasylol), lysine analogue anti-fibrinolytics [tranexamic acid (Cyclokapron) and epsilon aminocaproic acid (Amicar)], DDAVP (Desmopressin) and recombinant Factor VIIa (NovoSeven), in preventing the need for blood and blood-component therapies after major (cardiac, hepatic and orthopaedic/trauma) surgery. The data show that aprotinin is consistently effective in reducing globally the transfusion burden in cardiac and hepatic surgical procedures. However, there are little data to support its use in routine elective orthopaedic surgery. Multiple studies have failed to show an increased risk for myocardial ischaemia or infarction with aprotinin, and there may even be a reduced incidence of perioperative stroke in patients undergoing cardiac surgery. An increased probability of a hypersensitivity reaction when the drug is readministered within a 6-month period remains a significant issue. The data for the lysine analogue anti-fibrinolytics show no evidence of efficacy in reducing the transfusion burden for epsilon aminocaproic acid and inconsistent results with tranexamic acid in cardiac and hepatic surgery. As with aprotinin therapy, there is a paucity of data to support their use in routine elective orthopaedic surgery. There are no data to support the routine use of DDAVP to reduce the transfusion burden. Limited data suggest that this drug may be effective when a defect in platelet function is demonstrated. This aspect deserves further investigation. Recombinant activated Factor VII (rFVIIa) has proven benefit for its licensed indication to reduce bleeding in haemophiliacs with inhibitors to Factors VIII and IX. Reports of benefit in other instances are largely anecdotal. Hence, at this time it is therefore speculative and premature to suggest whether there is a place for this agent in routine clinical practice. No adequately powered, placebo-controlled prospective studies are available to investigate the safety of the lysine analogues, DDAVP or rFVIIa in cardiac, hepatic or orthopaedic surgery.
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PMID:Pharmacological approaches to reducing allogeneic blood exposure. 1254 28

The delta(2)- 1,2,3- triazoline anticonvulsants (TRs) may be considered as representing a unique class of "built-in" heterocyclic prodrugs where the active "structure element" is an integral part of the ring system and can be identified only by a knowledge of their chemical reactivity and metabolism. Investigations on the metabolism and pharmacology of a lead triazoline, ADD17014 suggest that the triazolines function as "prodrugs" and exert their anticonvulsant activity by impairing excitatory amino acid (EAA) L-Glutamate (L-Glu) neurotransmission via a unique "dual-action" mechanism. While an active primary beta-amino alcohol metabolite from the parent prodrug acts as an N-methyl-D-aspartate (NMDA)/MK -801 receptor antagonist, the parent triazoline impairs the presynaptic release of L-Glu. Various pieces of theoretical reasoning and experimental evidence have led to the clucidation of the dual-action mechanism. Based on the unique chemistry of the triazolines, and their metabolic pathways, biotransformation products of TRs were predicted to be the beta-amino alcohols V and VA, the alpha-amino acid VI, the triazole VII, the aziridine VIII and the ketimine IX. In vivo and in vitro pharmacological studies of the TR and potential metabolites, along with a full quantitative urinary metabolic profiling of TR indicated the primary beta-amino alcohol V as the active species. It was the only compound that inhibited the specific binding of [3H]MK-801 to the MK-801 site, 56% at 10 micro M drug concentration, but itself had no anticonvulsant activity, suggesting TR acted as a prodrug. Three metabolites were identified; V was the most predominant (45.7 +/- 7.6) % of administered drug, with lesser amounts of VA, (17.3 +/- 5.1) % and very minor amounts of aziridine VIII (4.0 +/- 0.02)%. Since only VIII can yield VA, its formation indicated that the biotransformation of TR occurred, at least in part, through aziridine. No amino acid metabolite was detected, which implied that no in vivo oxidation of V or oxidative biotransformation of TR or aziridine by hydroxylation at the methylene group occurred. While triazoline significantly decreased Ca(2+) -dependent, k(+)-evoked L-Glu release (83% at 100 micro M drug concentration ), some triazolines showed an augmentation of 50-63%, in the Cl(-) channel activity, a useful membrane action that reduces the excessive L-Glu release that occurs during epileptic seizures. The high anticonvulsant activity of TRs in a variety of seizure models including their effectiveness in the kindling model of complex partial seizures may be due to their unique dual-action mechanism whereby the TR and V together effectively impair both pre- and postsynaptic aspects of EAA neurotransmission; thus the TRs have clinical potential in the treatment of complex partial epilepsy which is refractory to currently available drugs. Since there is strong evidence that L-Glu plays an important role in human epilepsy as well as in brain ischemia/stroke, and since the TRs act by inhibiting EAA neurotransmission, it was logical to expect that the anticonvulsant TRs may evince beneficial therapeutic potential in cerebral ischemia resulting from stroke as well. And indeed, several TRs, when tested in the standard gerbil model of global ischemia did evince remarkable ability to prevent neuronal death.
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PMID:Rational drug design and the discovery of the delta2-1,2,3-triazolines, a unique class of anticonvulsant and antiischemic agents. 1287 Oct 87

Light to moderate drinking is associated with lower risk of coronary heart (CHD) than non-drinkers. We have examined the relationships between total alcohol intake and type of alcoholic beverage and several potential biological mechanisms. We carried out the study in 3158 men aged 60-79 years drawn from general practices in 24 British towns with no history of myocardial infarction, stroke or diabetes and who were not on warfarin. Total alcohol consumption showed a significant positive dose-response relationship with high density lipoprotein cholesterol (HDL-C), coagulation factor IX, haematocrit, blood viscosity, and tissue plasminogen (t-PA) antigen, and an inverse dose-response relationship with insulin, fibrinogen, von Willebrand factor (vWF) and triglycerides after adjustment for possible confounders. Total alcohol consumption showed weak associations with plasma viscosity and fibrin D-dimer, and no association with factors VII, VIII, or C-reactive protein (CRP). Wine was specifically associated with lower CRP, plasma viscosity, factor VIII and triglycerides. The findings are consistent with the suggestion that HDL-C in particular but also insulin and haemostatic factors may contribute to the beneficial effect of light to moderate drinking on risk of CHD. Wine has effects that may confer greater protection than other alcoholic beverages.
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PMID:The effects of different alcoholic drinks on lipids, insulin and haemostatic and inflammatory markers in older men. 1465 40

Cardiovascular diseases are still the main cause of morbidity and mortality in the world. Anti-platelet drugs have found clinical application in the secondary prevention of vascular events including acute myocardial infarction, stroke and cardiovascular death. In the present review, we have developed sixteen quantitative structure-activity relationships (QSAR) for different sets of compounds that are X-phenols (I), X-catechols (II), caffeic acid amides (III), X-alcohols (IV), 1,4-naphthoquinones (V), tetrahydronaphthalenes (VI), phenoxyacetaldehyde guanylhydrazones (VII), pyrrolobenzylisoquinolines (VIII) and phosphonic acids (IX) with respect to their anti-platelet activities. QSAR results have shown that the anti-platelet activities of these compounds are largely dependent not only on their hydrophobicity, but also on the influence of their molar refractivity.
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PMID:A classical QSAR study on some platelet aggregation inhibitors. 1661 84

Through a series of successive, cascade-like proteinase activation and amplification steps, any vascular injury triggers a rapid burst of alpha-thrombin, a trypsin-like serine proteinase. Thrombin, the main executioner of the coagulation cascade, has procoagulant as well as anticoagulant and antifibrinolytic properties. It exhibits quite diverse physiological functions, but also gives rise to several thrombotic disorders, such as thromboembolism, myocardial infarction, and stroke, thus making it an attractive target for antithrombotic agents. Thrombin interacts specifically with several protein substrates, receptors, cofactors, inhibitors, carbohydrates, and modulators. It cleaves fibrinogen, factors XI (FXI) and FXIII, cofactors V and VIII, and the thrombin receptors; uses thrombomodulin to activate protein C and thrombin-activatable-fibrinolysis inhibitor; is inhibited by heparin cofactor II and antithrombin III with the help of acidic carbohydrates; and its activity/specificity is modulated by sodium ions. A large number of crystal structures of alpha-thrombin in complexes with synthetic polypeptides and protein inhibitors, substrate fragments, cofactors, and carbohydrates have displayed extended recognition sites on the thrombin surface, reflecting the versatility and multifunctional specificity of this remarkable proteinase. These structures essentially show that the thrombin surface can be subdivided into several functional regions, which recognize different chemical moieties. By using different combinations of these surface elements, thrombin can interact with a variety of molecules with high specificity, accounting for its multifunctional properties.
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PMID:The structure of thrombin: a janus-headed proteinase. 1667 63


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