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

The spectrum of disorders associated with an elevated blood pressure (BP) encompasses chronic uncomplicated hypertension and the hypertensive crises, including hypertensive urgencies and emergencies. Although these syndromes vary widely in their presentations, clinical courses, and outcomes they share pathophysiologic mechanisms and, consequently, therapeutic responses to specifically targeted antihypertensive drug types. Nevertheless, hypertensive crises are often treated with drugs which, in that setting are either unsafe or are of unsubstantiated efficacy. The purpose of this review is to examine the pathophysiology of commonly encountered hypertensive crises, including stroke, hypertensive encephalopathy, aortic dissection, acute pulmonary edema, and preeclampsia-eclampsia and to provide a rational approach to their treatment based upon relevant pathophysiologic and pharmacologic principles. Measurement of plasma renin activity (PRA) level often provides insight regarding pathophysiology and predicts efficacy of antihypertensive treatments in the individual patient. However, in hypertensive crises, drug therapy is initiated before the PRA level is known. Nevertheless, the renin-angiotensin dependence (R-type) or volume dependence (V-type) of hypertension can often be deduced by the BP response to drugs that interrupt the renin system (R-drugs) or that decrease body volume (V-drugs). Based upon these considerations, a treatment algorithm is provided to guide drug selection in patients presenting with a hypertensive crisis.
 ...
PMID:Management of hypertensive crises: the scientific basis for treatment decisions. 1172 16

Magnesium exhibits a range of neuronal and vascular actions that may ameliorate ischaemic CNS insults, including stroke. Significant neuroprotection with magnesium has been observed in different models of focal cerebral ischaemia in many laboratories, with infarct volume reductions between 25 and 61%. Maximal neuroprotection is evident at readily attainable serum concentrations, and neuroprotection is still seen when administration is delayed up to 6 hours after onset of ischaemia. Clinical use of magnesium in pre-eclampsia and acute myocardial infarction confirms its safety and tolerability. Five small trials in acute stroke have reported reduced odds of death or dependence with administration of magnesium, but confidence intervals are wide, and definitive data from ongoing large trials are awaited.
 ...
PMID:Magnesium for neuroprotection in ischaemic stroke: rationale for use and evidence of effectiveness. 1173 12

Glucocorticoid remediable hyperaldosteronism (GRA) is a monogenic form of inherited hypertension caused by a chimeric gene originating from an unequal cross-over between the 11 beta-hydroxylase (CYP11B1) and aldosterone synthase (CYP11B2) genes. GRA is characterized by high plasma levels of aldosterone (regulated by ACTH) with suppressed plasma renin activity and the production of two rare steroids, 18hydroxycortisol and 18oxocortisol. Affected patients usually show severe hypertension and an elevated frequency of stroke at a young age. Affected women have a high risk of developing preeclampsia during pregnancy. Here, we describe a 5-generation pedigree from Sardinia in which the presence of the chimeric gene is demonstrated in 4 generations. This family displays a mild phenotype with average blood pressure levels of 131/86 mm Hg for GRA+ patients. The occurrence of stroke is very low, and preeclampsia was not observed in 29 pregnancies from 8 GRA+ mothers. We investigated whether the cross-over site (between the CYP11B1 and CYP11B2 genes) or biochemical characteristics could explain this phenotype. The cross-over site was located at the end of intron 3, in the same region as described in other families. We found a significant correlation between blood pressure and 18hydroxycortisol, 18oxocortisol, and plasma aldosterone levels, but not with kallikrein. However, none of the biochemical or genetic parameters investigated could explain the mild phenotype of the family.
 ...
PMID:Glucocorticoid remediable aldosteronism: low morbidity and mortality in a four-generation italian pedigree. 1210 22

In both developed and developing countries, women with high blood pressure who use oral contraceptives (OCs) face at least three times the relative risk of heart attack or ischemic stroke and 10 times the risk of hemorrhagic stroke than OC users without hypertension. A hypertensive OC user who smokes is at even greater risk. In general, combined OC use is contraindicated in women with severe hypertension (180/110 mm Hg or greater), hypertension with related vascular disease, or moderate hypertension (160-179/100-109 mm Hg). However, any contraception-related risks in hypertensive women must be weighed against those of pregnancy. Hypertensive pregnancies are associated with increased risks of pre-eclampsia, intrauterine growth retardation, premature delivery, and fetal death.
 ...
PMID:Hypertension raises method choice cautions. 1229 62

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.
 ...
PMID:Coping with hypertension in pregnancy. 1234 38

Hyperhomocysteinemia (HHCY) is a consequence of disturbed methionine metabolism. It results from enzyme and/or vitamin deficiency. Epidemiological and clinical studies have proven HHCY to be an independent risk factor for atherosclerotic cardiovascular diseases, stroke, peripheral arterial occlusive disease and venous thrombosis. Trials in progress may clarify the "causality" of high homocysteine (HCY) concentrations and will assess the value of HCY lowering therapy. HHCY is also seen as a risk factor for neurodegenerative diseases such as cognitive impairment, dementia, Alzheimer's disease, and also for depression. There is a high prevalence of HHCY as a syndrome of vitamin shortage in elderly subjects, which strongly increases with advancing age. Elderly people have a high frequency of vitamin B12 deficiency which is more reliably diagnosed by measurement of serum methylmalonic acid and holotranscobalamin II, the metabolically active B12 fraction, than by total serum vitamin B12. Subjects who follow a strict vegetarian diet also have a high prevalence of HHCY caused by vitamin B12 deficiency. For prevention of neurological damages an early diagnosis of vitamin B12 deficiency is important. Furthermore, HHCY is a factor in the pathogenesis of neural tube defects and preeclampsia. HCY should be measured in patients with a history of atherothrombotic vessel diseases, in patients with diabetes or hyperlipidemia, in renal patients, in adipose subjects, in elderly people, in vegetarians, in postmenopausal women, and in early pregnancy.
 ...
PMID:Hyperhomocysteinemia: a new risk factor for degenerative diseases. 1238 6

Hypertension is the most common medical disorder during pregnancy. Chronic hypertension is a serious medical complication in pregnancy with increased maternal and perinatal morbidity and mortality. Those who develop uncontrolled severe hypertension, those with target organ damage, and those who are poorly compliant with prenatal visits are at high risk for poor perinatal outcome. Maternal complications include abruptio placenta, stroke, and superimposed pre-eclampsia. Fetal complications include prematurity, low birth weight, and perinatal death. Careful antepartum, intrapartum and postpartum management of women with high-risk chronic hypertension in pregnancies may reduce morbidity and mortality.
 ...
PMID:Chronic hypertension in pregnancy. 1259 38

We investigated the distribution of the prothrombin variant G20210A (PT20210A) in a sample of 103 patients (mean age: 34.5 years) living in the French Basque Country and presenting with conditions known to be significantly associated with this peculiar mutation according to a literature review. These patients suffered from repeated personal or familial venous thromboses, stroke at young age, or repetitive maternal-fetal disorders (abortions, preeclampsia, fetal growth retardation). Five patients (4.8%) were found to be carriers: two homozygotes and three heterozygotes (one also heterozygote for factor V Leiden). Of note, two presented with mesenteric venous thrombosis. The distribution of PT20210A among our sample was comparable to data from Western European series albeit a tendency for lower mutation prevalence was observed in our subgroup with obstetrical disorders. In addition, no significant difference in PT20210A frequency was evidenced between autochthonous Basques and individuals from other origins.
 ...
PMID:Assessment of the 20210 G to A prothrombin variant in a sample of patients from the French Basque Country with various thrombophilic conditions. 1273 76

The classical clinical picture of the antiphospholipid syndrome (APS) is characterized by venous and arterial thromboses, fetal losses and thrombocytopenia, in the presence of antiphospholipid antibodies (aPL), namely lupus anticoagulant (LA), anticardiolipin antibodies (aCL), or antibodies to the protein "cofactor" b2 glycoprotein I. Single vessel involvement or multiple vascular occlusions may give rise to a wide variety of presentations. Any combination of vascular occlusive events may occur in the same individual and the time interval between them also varies considerably from weeks to months or even years. Deep vein thrombosis, sometimes accompanied by pulmonary embolism, is the most frequently reported manifestation in this syndrome. Cerebrovascular accidents-either stroke or transient ischemic attacks-are the most common arterial thrombotic manifestations. Early and late fetal losses, premature births and pre-eclampsia are the most frequent fetal and obstetric manifestations. Additionally, several other clinical features are relatively common in these patients, i.e., thrombocytopenia, livedo reticularis, heart valve lesions, hemolytic anemia, epilepsy, myocardial infarction, leg ulcers, and amaurosis fugax. However, a large variety of other clinical manifestations have been less frequently described in patients with the APS, with prevalences lower than 5%. These include, among others, large peripheral or aortic artery occlusions, Sneddon's syndrome, chorea, transverse myelopathy, intracardiac thrombus, adult respiratory distress syndrome, renal thrombotic microangiopathy, Addison's syndrome, Budd-Chiari syndrome, nodular regenerative hyperplasia of the liver, avascular necrosis of the bone, cutaneous necrosis or subungual splinter hemorrhages. In this article, some of these "unusual" manifestations are reviewed.
 ...
PMID:Unusual manifestations of the antiphospholipid syndrome. 1279 62

Prothrombotic disorders are believed to be important contributors to the etiology of peri- and neonatal arterial ischemic stroke and sinovenous thrombosis, which may lead to life-long disability. This article reviews hematological issues unique to the perinatal period, including: the significance of the placenta as the interface between maternal and fetal circulations; normal changes in the coagulation system of mothers during and just after gestation; and the significance of prothrombotic disorders in the mother and/or fetus. Other possible maternal and neonatal contributors to peri- and neonatal stroke are discussed, including: infection, pre-eclampsia, diabetes, and drug use in the mother; and infection, dehydration, complex congenital heart disease, extracorporeal membrane oxygenation, and catheter placement in the neonate. Possible approaches to preventing and treating perinatal and neonatal stroke are presented.
 ...
PMID:The contribution of prothrombotic disorders to peri- and neonatal ischemic stroke. 1451 53


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