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)

The purpose of the study was to determine the relevance of protein S deficiency in HIV infected patients with ischaemic stroke. In total, 33 HIV positive patients with ischaemic stroke, previously described by us, were prospectively compared with control groups for occurrence of protein S deficiency. The control groups comprised an equal number of consecutive matched HIV positive and negative patients without and with stroke respectively. Data were analysed in contingency tables using Fisher's exact test. Protein S deficiency occurred significantly more frequently in HIV positive compared with HIV negative stroke patients (p < 0.001). However, by including HIV positive patients without stroke as a control group and comparing this group with the HIV positive stroke group we found that protein S deficiency is statistically related to HIV infection and not stroke occurrence. Our data indicate that the presence of protein S deficiency in HIV positive patients with stroke is an epiphenomenon of HIV infection.
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PMID:Protein S deficiency in HIV associated ischaemic stroke: an epiphenomenon of HIV infection. 1617 70

Moyamoya disease (MMD) is a vascular abnormality characterized by progressive narrowing of the internal carotid, middle, anterior and posterior cerebral arteries and the development of basal collaterals forming the classic angiographic appearance-moyamoya. Protein C (PC) and its cofactor, protein S (PS), which are vitamin-K dependent, act as inhibitors of coagulation cascade by inactivating factor Va and factor VIIIa and facilitating thrombolysis. Deficiencies of these proteins leading to a prothrombotic state increase the risk of ischemic cerebrovascular accident. Herein we report a 3-year-old girl, who had an acute onset of right-side hemiparesis during an episode of herpetic gingivostomatitis. She was noted to have moyamoya syndrome in the angiographic examination and was later proved to have inherited deficiencies of both PC and PS. She received warfarin medical treatment and then bilateral encephalo-duro-arterio-synangiosis (EDAS) and encephalo-myo-synangiosis (EMS) due to neurological deterioration and is now under the use of low molecular weight heparin for preventing further ischemic stroke. The motor deterioration improved after medical and surgical intervention. We conclude that coagulopathy like PC or PS deficiency should be considered in children presenting with moyamoya syndrome.
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PMID:Moyamoya syndrome with inherited proteins C and S deficiency: report of one case. 1630 75

Thrombophilia by definition represents acquired and/or genetic conditions that predispose patients to both venous and arterial thromboembolic events. Thrombosis is the most common cause of death worldwide. On the arterial side, myocardial infarction and stroke result in significant morbidity and mortality. Venous thromboembolic events most commonly involve the deep veins of the lower extremity with potential complications of pulmonary emboli. Pregnancy is a hypercoagulable state, and thromboembolism is the leading cause of antepartum and postpartum maternal mortality. With the description by Dahlback in 1993 of a condition initially labeled activated protein C resistance, significant advances have rapidly followed. Activated protein C resistance was linked to an underlying point mutation resulting in coagulation factor V (factor V Leiden). Recent attention has focused on certain inherited thrombophilic factors that may predispose to arterial and/or venous thromboses and their possible association with pregnancy complications, including early pregnancy loss. These include a group of mostly autosomal dominant, inherited gene mutations leading to a hypercoagulable state, such as factor V Leiden G1691A, factor II or prothrombin G20210A, and hyperhomocysteinemia associated with methylenetetrahydrofolate reductase C677T mutation. In addition, deficiencies in protein S, protein C, and antithrombin can lead to a hypercoagulable state. Although some studies of recurrent pregnancy loss patients with a positive test for an inherited thrombophilia are conflicting, a case-control study of untreated recurrent miscarriage patients who were heterozygous for the factor V Leiden mutation revealed a lower success rate than the controls who had a history of idiopathic recurrent miscarriage. With the identification of genetic risk factors, there has been synergistic amplification of thrombotic risk when one has an abnormal gene (e.g., factor V Leiden) plus environmental issues (e.g., pregnancy). Current understanding indicates that a combination of risk factors, including multiple inherited thrombophilic defects associated with secondary hypercoagulable states, have a particularly strong association with adverse pregnancy outcome.
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PMID:Thrombophilias and recurrent pregnancy loss. 1641 78

Protein C (PC), protein S (PS), antithrombin III, and plasminogen are four important anticoagulants in blood plasma. Deficiency of any of these biomolecules may lead to thrombo-embolic complications including lung embolism, heart attack, and stroke. A multi-factor sensing system is beneficial for identifying the cause of abnormal blood clotting more effectively, rapidly, and cost-effectively. As an initial effort toward simultaneous multi-anticoagulant detection, a PC and PS dual-sensing system has been under development in our research group. A fiberoptic PC biosensor utilizing fluorophore-mediated sandwich immunoassay was already developed for rapid (-5 minutes) PC deficiency diagnosis. After a single PS sensor was developed for the PS deficiency diagnosis, the two sensors were connected in series to form a dual-sensing system. The cross-reactivity between the analytes and the sensors was found to be minimal. For easier sensing operation, a mixture of fluorophore-linked anti-PC and anti-PS was applied. The results showed that the mixture can be used with a slight signal reduction. When PC and PS was mixed in a sample, the signal intensity was decreased by approximately 5% for both sensors. A study is currently being performed to overcome the signal reduction by increasing the flow velocity and incubation time.
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PMID:Preliminary study of simultaneous multi-anticoagulant deficiency diagnosis by fiber optic multi-analyte biosensor. 1659 66

Cardiopulmonary bypass (CPB) poses great risks for hypercoagulable patients and requires management techniques to ensure an optimal outcome free from thrombotic events. This case report reviews perfusion management techniques that may contribute to a safer CPB experience for a patient deficient in both protein C and protein S. A patient with heterozygous protein C deficiency is at increased risk of thrombosis, especially in the venous circulation. Since it is an essential cofactor for activated protein C, deficiency of free protein S is also linked to a hypercoagulable condition. A 52-year-old male presented to our institution with a past medical history of hypercoagulable state, multiple deep vein thromboses, pulmonary embolisms, and stroke. He was scheduled for two-vessel coronary artery bypass graft surgery to be followed by right carotid endarterectomy (RCEA) before discharge. The anesthesia and perfusion teams worked closely together to ensure that fresh frozen plasma (FFP) was given intraoperatively at appropriate times. Heparin dose response and protamine dosage was determined with hemostasis management system (HMS) analysis. The closed CPB circuit and cannulae were Carmeda bonded. Rapid autologous priming, along with the use of a hemoconcentrator, kept the hematocrit above 21 during CPB. Zero-balance ultrafiltration and leukocyte depletion were initiated during rewarming to aid in attenuation of the inflammatory response. To conserve coagulation factors, all pump blood was ultrafiltrated post-CPB and returned to the patient. Laboratory samples drawn on postoperative day (POD) one measured normal protein C activity with subnormal protein S activity. On POD six, the patient underwent RCEA and he was discharged on POD eight without complications.
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PMID:Cardiopulmonary bypass for a coronary artery bypass graft patient with heterozygous protein C deficiency and protein S deficiency. 1661 90

Since the introduction of echocardiography the diagnosis of papillary fibroelastomas (PFEs) in living patients has increased. They are second most common after myxomas representing 10% of cardiac tumors. The present case is of a patient with recurrent cerebrovascular accidents and documented protein S deficiency who continued to stroke despite adequate anticoagulation. Mitral valve PFE was suspected on echocardiography and confirmed at surgical excision. Two large studies published in the last decade describe the echocardiographic and clinical characteristics of PFEs which although are histologically benign, may present with a clinical course of devastating consequences owing to its strategic location within the cardiac structures. Echocardiography, particularly transesophageal echocardiography (TEE), provides the necessary anatomical resolution and detail to ascertain location, extent of involvement, and hemodynamic implications. Tissue diagnosis is based on characteristic histopathological features of avascular fronds lined by endothelial cells, containing varying amounts of elastin. The echocardiographic characteristics along with treatment options are reviewed.
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PMID:Recurrent strokes in a young patient with papillary fibroelastoma: a case report and literature review. 1691 35

S-100 protein, described initially by Moore, constitutes a large family of at least 20 proteins with calcium binding ability. It is found as homo- or hetero-dimers of two different subunits (A and B). Types S-100AB and S-100BB are described as S-100B protein and are shown to be highly specific for nervous tissue. It is present in the cytosol of glial and Schwann cells, and also in adipocytes and chondrocytes, although in very low concentrations in the latter two. The role of protein S-100B is not yet fully understood. It is suggested that it has intracellular and extracellular neurotropic as well as neurotoxic function. At nanomolar levels, S-100B stimulates neurite outgrowth and enhances survival of neurons. However, at micromolar levels it stimulates the expression of inflammatory cytokines and induces apoptosis. Recently, serum S-100B protein has been proved to be an attractive surrogate marker of primary severe brain injury and secondary insults. It can be measured in the arterial and venous serum; it is not affected by haemolysis and remains stable for several hours without the need for immediate analysis. Its short half-life makes measurements crucial in the emergency and intensive care settings. This review summarises published findings on S-100B regarding its role as a serum biochemical marker of brain injury, i.e., after severe, moderate or mild neuro-trauma, subarachnoid haemorrhage, thrombo-embolic stroke, cerebral ischaemia and brain tumours, as well as extracranial trauma, neurodegenerative and psychiatric disorders.
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PMID:Serum S-100B protein as a biochemical marker of brain injury: a review of current concepts. 1716 33

Cerebral venous thrombosis (CVT) is rare compared to arterial causes of stroke. It is often encountered in young patients and may occur in children and neonates. Predisposition to CVT also has a genetic basis and inherited thrombophilias are known to cause 22.4% of the CVT cases. Inherited thrombophilias should be suspected if a patient has recurrent CVT, is less than 45 years age, has a family history of venous thrombosis or has no apparent acquired risk factor. Factor V Leiden (FVL) is the most common genetic risk factor, followed by the prothrombin gene mutation G20210A. Other less common inherited venous thrombophilias include deficiencies of Protein S, Protein C and antithrombin III. FVL, the G20210A prothrombin gene mutation and a deficiency of protein S and C, cause a reduction in the control of thrombin generation. Deficiency of antithrombin causes a decreased neutralization of thrombin. Both these mechanisms are responsible for venous thrombosis. Inherited thrombophilias with concomitant acquired risk factors like surgery, trauma, prolonged immobilization, pregnancy and puerperium, oral contraceptives, antiphospholipid antibodies and hyperhomocysteinemia may increase the risk of CVT manifold. Similarly the co-inheritance of two or more known mutations also increases the risk markedly. FVL, prothrombin G20210A mutation, increased factor VIIIc, protein C & S deficiency and antithrombin III deficiency have all been reported to cause neonatal stroke due to CVT. Maternal and foetal testing is suggested when CVT occurs in neonates.
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PMID:Genetics of cerebral venous thrombosis. 1718 72

This review focuses on the several coagulation disorders (the so called hypercoagulable states) that are associated with cerebral venous thrombosis. Hypercoagulable states likely explain the high percentage of cases of cryptogenic cerebral infarction in young people. The most common of the hereditary defects appear to be deficiency of antithrombin III, protein C or protein S, activated protein C resistance and prothrombin 20211A mutation. In a large majority of cases activated protein C resistance is due to the presence of factor V Leiden. Antiphospholipid antibodies (lupus anticoagulant and anticardiolipin antibodies) represent an acquired disorder of coagulation. Rare defects include heparin cofactor II (HC II), plasminogen or tissue plasminogen activator deficiency (TPA), elevated plasminogen activator inhibitor-1 (PAI-1) and dysfibrinogenemia. Hyperhomocystinemia is responsible for both arterial and venous thrombosis. A work-up to identify one of the recognizable hypercoagulable states is indicated, especially in younger patients with stroke. Laboratory evaluation for hypercoagulable states may also often be indicated in those patients who do not have other obvious risk factors for their stroke. If from clinical history, family history and/or laboratory studies, a patient is felt to have a hypercoagulable state, the decision for long term chronic anticoagulation needs to be individualized. If a hereditary hypercoagulable state is found, it also may be appropriate to recommend screening of other family members.
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PMID:Haematologic disorders and cerebral venous thrombosis. 1718 75

We present the first reported case of antiphospholipid syndrome with stroke in an Iranian boy (7-month-old) who had two ischemic strokes within a period of 2 months. Serum anticardiolipid antibody was positive and the patient had low levels of protein S and C. This case emphasizes the importance of antiphospholipid antibody in children with unexplained ischemic stroke.
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PMID:Stroke in an infant; its association with antiphospholipid antibody and acquired protein C and s deficiencies. 1730 99


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