Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0020538 (hypertension)
 170,190 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Risk factors for intracerebral hemorrhage (ICH) and cerebral infarction (CI), were studied by a prospective study of 7,390 men and women aged 40-69 without a history of stroke living in three rural populations in Japan. Baseline examinations were done for populations in Akita-Ikawa and Akita-Ishizawa in 1975-1979, and for Ibaraki-Kyowa in 1981-1987, and followed until 1989 for Akita-Ikawa and Ibaraki-Kyowa and 1987 Akita-Ishizawa. There were 246 stroke cases diagnosed by clinical criteria during the follow-up period in which 74 percent (n = 181) had data from computed tomography (CT) performed within three weeks of the onset. According to these CT-findings, 181 stroke were classified as 48 with ICH, 50 with CI in penetrating artery regions (penetrating artery infarction), 33 with CI in cortical artery regions (cortical artery infarction), and 31 with subarachnoid hemorrhage while there were 19 with stroke without any evident CT abnormality. Cortical artery infarction was further classified as embolic type (n = 17) and thrombotic type (n = 9) according to clinical findings of the onset and presence of possible embolic sources such as atrial fibrillation, congenital heart disease, myocardial infarction and heart valve diseases. Using a nested case-control design, risk variables at baseline examination were compared between 131 stroke cases, 48 ICH and 83 CI, with 655 controls matched for sex, age (+/- 3), and the follow-up year. Univariate analysis showed that high blood pressure was associated with all types of stroke. From conditional logistic regression analysis significant risk variables were found to be high blood pressure for ICH and penetrating artery infarction, while atrial fibrillation and ST-T abnormality in electrocardiogram (ECG) were risk variables for cortical artery infarction. Associations with hypertensive or arteriosclerotic changes in ocular fundus were stronger for penetrating artery infarction than ICH and cortical artery infarction. ST-T abnormality in ECG was associated with embolic type cortical artery infarction and high blood pressure was associated with the thrombotic type, although the number of cases were small. Compared to controls, cortical artery infarction showed a higher mean value of serum total cholesterol for thrombotic type cortical infarction, and lower mean values for embolic type and ICH, but none of them reached statistical significance. The present study also suggests that duration of hypertension varied with type of stroke. ICH may develop due to acute effects of hypertension, while penetrating artery infarction and cortical artery infarction develop by chronic effects of hypertension.
 ...
PMID:[A nested case-control study of risk factors for intracerebral hemorrhage and cerebral infarction classified by computed tomographic findings]. 150 35

The goal of the current study was to determine whether treatment of hypertension reduces cerebral infarction after occlusion of the middle cerebral artery in stroke-prone spontaneously hypertensive rats (SHRSPs). Three-month-old SHRSPs received untreated drinking water or drinking water containing cilazapril, an angiotensin converting enzyme inhibitor, or hydralazine and hydrochlorothiazide. After 3 months of treatment, the left middle cerebral artery was occluded and neurological deficit was evaluated. Infarct volume was measured 3 days after occlusion using computer imaging techniques from brain slices. Cilazapril and hydralazine with hydrochlorothiazide were equally effective in reducing systolic blood pressure in SHRSPs. One day after occlusion of the middle cerebral artery, neurological deficit was decreased by both cilazapril and hydralazine with hydrochlorothiazide compared with untreated SHRSPs, and the deficit 3 days after occlusion was decreased significantly only by cilazapril. Infarct volume was 178 +/- 7 mm3 (mean +/- SEM) in untreated SHRSPs, and it was significantly reduced to 117 +/- 15 mm3 by hydralazine with hydrochlorothiazide and to 101 +/- 17 mm3 by cilazapril. Infarct volume in Wistar-Kyoto rats was 27 +/- 16 mm3. Thus, reduction in arterial pressure by hydralazine with hydrochlorothiazide or an angiotensin converting enzyme inhibitor is protective against focal cerebral ischemia in SHRSPs.
Hypertension 1992 Jun
PMID:Effect of antihypertensive treatment on focal cerebral infarction. 153 16

Prenatal cocaine use has become an increasingly important public health problem in the last decade. Interpretation of epidemiologic studies designed to assess the association between cocaine use and adverse pregnancy outcomes is limited by inaccurate measurement of cocaine use, misclassification of users as non-users, confounding by socioeconomic factors, and reporting bias. Studies have consistently documented placental abruption as a maternal reproductive risk associated with cocaine use. Although suggested, less evidence is available to link cocaine use with premature rupture of membranes, spontaneous abortion, pregnancy-induced hypertension, precipitate delivery, or fetal death. Infant outcomes consistently associated with prenatal cocaine use include decreased birth weight, prematurity, and decreased fetal growth. Data on the relationship between prenatal cocaine use and congenital anomalies are limited, but one large retrospective study has documented an association between maternal cocaine use and congenital abnormalities of the urinary tract. Evidence linking prenatal cocaine use and an increased incidence of perinatal cerebral infarction or sudden infant death syndrome is lacking. Future studies should focus on the effect of maternal cocaine use on pregnancy outcome in diverse socioeconomic groups, longitudinal follow-up of exposed children, and the relationship between cocaine use and maternal behaviors that may affect access to prenatal care.
 ...
PMID:Risks associated with cocaine use during pregnancy. 156 65

Neurogenic mechanisms are important in the maintenance of most forms of hypertension, yet the brain is highly vulnerable to the deleterious effects of elevated blood pressure. Hypertensive encephalopathy results from a sudden, sustained rise in blood pressure sufficient to exceed the upper limit of cerebral blood flow autoregulation. The cerebral circulation adapts to chronic less severe hypertension but at the expense of changes that predispose to stroke due to arterial occlusion or rupture. Stroke is a generic term for a clinical syndrome that includes focal infarction or hemorrhage in the brain, or subarachnoid hemorrhage. Atherothromboembolism and thrombotic occlusion of lipohyalinotic small-diameter end arteries are the principal causes of cerebral infarction. Microaneurysm rupture is the usual cause of hypertension-associated intracerebral hemorrhage. Rupture of aneurysms on the circle of Willis is the most common cause of nontraumatic subarachnoid hemorrhage. Stroke is a major cause of morbidity and mortality, particularly among persons aged 65 years or older. Treatment of diastolic hypertension reduces the incidence of stroke by about 40%. Treatment of isolated systolic hypertension in persons aged 60 years and older reduces the incidence of stroke by more than one third. Blood pressure management in the setting of acute stroke and the role of antihypertensive therapy in the prevention of multi-infarct dementia require further study.
 ...
PMID:Hypertension and the brain. The National High Blood Pressure Education Program. 158 Jul 19

We studied 925 consecutive patients hospitalised with acute stroke to determine how stroke type, age, gender and risk factors influence acute, in-hospital outcome. Stroke types included carotid territory cortical or large subcortical infarction (52%), vertebrobasilar infarction (12%), lacunar infarction (11%), intracerebral haemorrhage (16%), and subarachnoid haemorrhage (9%). Mean age (mean +/- 1 SD) was 66 +/- 15 years, but patients with cerebral infarction were older than those with cerebral haemorrhage. The prevalence of hypertension, diabetes mellitus and cardiac disease increased with age across all stroke types, while the prevalence of smoking decreased with age. Mortality was 19% overall, but varied significantly between stroke types, highest in intracerebral haemorrhage (34%), and lowest in lacunar infarction (1%). Age had a marked adverse effect on mortality, independent of stroke type, the probability of death increasing by 3 +/- 0.5% per year from 20-92 years, whereas gender had no effect. Cardiac disease and diabetes were independent adverse prognostic factors (Odds Ratios 1.6 and 1.5 respectively). Cerebral haemorrhage, age, cardiac disease and diabetes all independently worsen acute stroke outcome.
 ...
PMID:Acute stroke outcome: effects of stroke type and risk factors. 158 Aug 59

Clonidine, idazoxan, rilmenidine, and comparable agents bind to imidazol(in)e (IR), as well as alpha 2-adrenergic, receptors. Interaction with IRs mediates the hypotension elicited by these drugs at their site of action in the rostral ventrolateral medulla oblongata (RVL) and probably the neuroprotection in focal ischemic cerebral infarction. Unlike alpha 2-adrenergic receptors, IRs are not coupled to G-proteins. Their native ligand may be clonidine-displacing substance (CDS), a potent, partially purified adrenomedullary secretagogue, distributed regionally in brain and some peripheral organs. IRs and CDS may be important in the genesis, expression, and/or therapy of hypertension and stroke.
 ...
PMID:Imidazole receptors and clonidine-displacing substance in relationship to control of blood pressure, neuroprotection, and adrenomedullary secretion. 159 95

11 cases of cerebral venous thrombosis in adults are reported. Main clinical signs are: intracranial hypertension (headache, nausea, papilledema in 7 cases, loss of consciousness in 6 cases, neurological deficit in 6 cases, seizure in 4 cases. 1 patient is dead, who did not receive heparin treatment. Delay before diagnosis is between 2 and 20 days, and is shortened when arteriography or MRI are available and prescribed. At least one (or several) CT examination was performed in 10 patients. Direct signs of thrombosis are uneasily detected without contrast injection, seen here in 4 cases. Empty delta sign is observed in 7 patients, lately in 4 cases, and once only afterwards. Cerebral infarction is visualized in 7 cases over 10. Its features frequently seem evocative for cerebral venous thrombosis: triangularin 4 cases or nodular shape in 3 cases with hemorragic infarct in 7 cases, with bilateral topography in 6 cases, in frontal or central areas in 7 cases. 6 patients had a MRI examination. All cerebral infarctions appeared haemorragical, even at early stages. During subacute period, venous thrombosis is constantly and easily detected by the mean of methemoglobin high signal intensity on T1 weighted images. The prediagnosis delay is short, without necessity of arteriography. MRI should take the place of CT and arteriography in investigation of a clinically suspected cerebral venous thrombosis.
 ...
PMID:[Thrombosis of the cerebral veins. X-ray computed tomography and MRI imaging. 11 cases]. 160 50

During carotid endarterectomy (CEA), phenylephrine infusions are commonly used to induce hypertension during carotid clamping in an attempt to increase collateral cerebral blood flow and prevent cerebral ischemia. Although this practice appears to increase the incidence of intraoperative myocardial ischemia during CEA when general anesthesia is employed, whether the limited use of phenylephrine infusions in specific instances of cerebral ischemia, as shown on an electro-encephalogram, results in low perioperative rates of both myocardial infarction (MI) and cerebral infarction remains unclear. We studied 171 CEAs done under general anesthesia performed with selective shunting based on the identification of cerebral ischemia by a two-channel computerized electroencephalographic monitor. The use of a phenylephrine infusion was restricted to the following instances of cerebral ischemia: 1) ischemia associated with hypotension that did not resolve within 2 minutes of decreases in anesthetic administration and treatment with fluid and/or colloid; 2) ischemia poorly or slowly responsive to shunt placement, accompanied by either hypo- or normotension; and 3) ischemia poorly or slowly responsive to removal of the carotid clamp, accompanied by either hypo- or normotension. Two non-Q wave MIs (1.2%) occurred, both nonfatal. There were two cerebral infarctions (1.2%) and three deaths not related to MI (1.8%). Based on these findings, in order to decrease the incidence of both MI and cerebral infarction after general anesthesia for CEA, we recommend the restrictive use of phenylephrine-induced hypertension for specific instances of slowly or poorly reversible cerebral ischemia, as shown on the electroencephalogram.
 ...
PMID:Computerized electroencephalographic monitoring and selective shunting: influence on intraoperative administration of phenylephrine and myocardial infarction after general anesthesia for carotid endarterectomy. 161 84

To characterise the pathogenetic and prognostic features of lacunar infarcts, 88 patients with these infarcts were compared with 103 patients with non-lacunar infarcts. Potential cardioembolic sources were significantly more frequent among patients with non-lacunar infarcts (p = 0.0025). Although the prevalence of hypertension was higher among lacunar infarcts, this difference was not statistically significant. However, the distribution of hypertensive patients in the two groups of lacunar and non-lacunar infarcts was influenced by the presence or absence of cardioembolic sources: hypertension was significantly associated with the presence of cardioembolic sources among non-lacunar infarcts, whereas among lacunar infarcts it was significantly more frequent in patients without a cardioembolic source. This indicates that cardioembolism may exert a confounding effect by suppressing the relation between hypertension and lacunar infarcts. In a mean follow up period of 28.1 months, lacunar infarcts had a significantly lower incidence of stroke recurrence and of myocardial infarction (age-adjusted survival analysis: p = 0.0008); mortality from all causes was also lower in patients with lacunar infarct (age-adjusted survival analysis: 0.04 less than p less than 0.05). In a multivariate regression analysis, stroke subtype was an independent predictor of new major vascular events. These findings support the lacunar hypothesis and should be considered in the planning of epidemiological and therapeutic studies in patients with cerebral infarction.
 ...
PMID:Lacunar versus non-lacunar infarcts: pathogenetic and prognostic differences. 161 8

The role of alcohol as a risk factor for cerebral infarction and hemorrhage has been assesed in 200 middle-aged and elderly stroke patients and 200 controls matched for age, sex and hospital admission date. Computed tomographic brain scans were done in all but 10 of the stroke patients. Alcohol intake was reckoned on the 12 months preceding hospitalization and expressed in grams daily according to a standard nomogram. The Michigan Alcoholism Screening Test was used for the diagnosis of alcoholism. Cerebral infarction was present in 59% of the stroke patients and cerebral hemorrhage in 9%. The role of alcohol as risk factor for stroke proved to be small (Odds Ratio 1.86) and was practically lost after adjustment for the most common risk factors for cerebrovascular disorders (previous strokes, arterial hypertension, diabetes, obesity and hyperlipidemia). Our findings seem to suggest that alcohol is not an independent risk factor for stroke in the middle-aged and elderly. The data are, however, preliminary and are discussed in the light of methological problems.
 ...
PMID:Cerebrovascular disorders and alcohol intake: preliminary results of a case-control study. 162 76


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