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 article discusses the results of experiments on 16 dogs in which acute myocardial ischemia was reproduced with intravenous infusion of baksacor and without the infusion of the drug; control experiments were also performed on an intact heart with baksacor infusion. Hemodynamics and myocardial contractility were studied throughout the entire experiment. It was found that baksacor had practically no effect on an intact heart. In acute ischemia the maximum effect of the drug was manifested on the 5th-25th minutes. An increase of the stroke volume and normalization of the rate of shortening of the contraction component were observed. An anti-arrhythmic effect of baksacor was noted.
 ...
PMID:[Effect of baxacor on the hemodynamics and contractile function of the myocardium in acute ischemia (an experimental study)]. 64 42

Hypoxia is well known to cause an increase in brain anaerobic glycolysis. Ornithine alpha ketoglutarate (OAKG) given to six dogs was shown to attenuate these metabolic disturbances caused by hypoxia. Brain oxygen utilization was higher after ornithine alpha ketoglutarate during hypoxia than during a period of hypoxia alone. It is suggested that the clinical usefulness of OAKG should be explored in those situations where there is cerebral hypoxia or ischemia.
Stroke
PMID:Effect of ornithine alpha ketoglutarate (OAKG) on the response of brain metabolism to hypoxia in the dog. 64 19

Ischemic brain damage can be partially ameliorated by barbiturate therapy applied postinsult. Catabolism-induced brain hyperosmolality during ischemia may contribute to the development of brain edema after restoration of circulation. To determine changes in brain osmolality during ischemia and the effect of barbiturate anesthetics in altering its course, we measured whole and regional (cerebral cortex, diencephalon-midbrain, and cerebellum) brain osmolality for up to 2 hours after decapitation ischemia in unanesthetized and pentobarbital anesthetized rats. Normal (nonischemic) brain osmolality in pentobarbital anesthetized rats was 319 +/- 2 mOsm/1 (mean +/- SEM) and higher than in unanesthetized rats (307 +/- 6 mOsm/1). The rate of increase in whole brain osmolality was 60% slower in pentobarbital anesthetized rats in the first 60 minutes of ischemia and regional brain osmolality increased by a maximum of 32 mOsm/1 compared to 45 mOsm/1 in unanesthetized rats. The potential for edema based on percent change in brain osmolality as well as the rapidity of the change was greater in unanesthetized rats. The significance of the increase in brain osmolality with barbiturate anesthesia and its attenuation of the rate and magnitude of increase during ischemia is discussed.
Stroke
PMID:Rat brain osmolality during barbiturate anesthesia and global brain ischemia. 64 23

Seizure activity as a component of the ischemic process possibly responsible for monoamine changes described in the gerbil stroke model was the subject of this study. Abnormal motor activity suggestive of seizures developed one to three hours after unilateral ligation of the common carotid artery in approximately 50% of gerbils that exhibited signs of stroke. Reduction of cortical levels of dopamine and norepinephrine was observed only when seizures occurred in association with stroke. The levels of 5-hydroxytryptamine were reduced bilaterally in animals with and without signs of stroke and were reduced further in animals with stroke plus seizures. Further study is needed to establish whether the catecholamine changes associated with ischemia-induced seizures are primary and causative or secondary to seizure activity itself. In the ischemic brain, 5-hydroxytryptamine metabolism appears disordered independent of seizure activity. Seizure activity must be taken into account when the mechanisms of disordered monoamine metabolism are being examined in the gerbil stroke model.
 ...
PMID:Ischemia-induced seizures and cortical monoamine levels. 65 65

We evaluated the effects of methylprednisolone sodium succinate (MPSS) on 60 minutes of myocardial ischemia during profound (5 degrees C) topical cardiac hypothermia (ice chips) in a canine right heart bypass preparation. The ventricular function curve shifted to the right and downward, but not significantly, after ischemia, and stroke work declined significantly for both control and treated dogs. Contractility (rate of rise of left ventricular pressure and maximum velocity of the contractile element) declined for both groups but not significantly. Total coronary flow, oxygen consumption, and metabolism of lactate and pyruvate were not different for control and treated dogs. Ultrastructure of the outer and inner myocardium did not demonstrate benefit from MPSS. Intracellular and extracellular edema of moderate severity was slightly worse in the subendocardium, and reversible mitochondrial injury of a mild to moderate degreee was symmetrically present. Ice-related injury was not noted. We were unable to deomonstrate that pretreatment with MPSS favorably alters cardiodynamics or ultrastructure after 60 minutes of profound topical cardiac hypothermia.
 ...
PMID:Topical cardiac hypothermia: the effect of methylprednisolone sodium succinate. 65 47

We compared ejection fraction, left ventricular end-diastolic pressure, cardiac index and the relation of left ventricular stroke work index to left ventricular end-diastolic pressure during rest and exercise in 60 patients with coronary artery disease. Left ventricular end-diastolic pressure was usually normal at rest (48/60) and abnormal during exercise (46/60) and did not correlate with ejection fraction. Cardiac index was insensitive, usually remaining normal until ejection fraction was less than 0.40. Patients with a normal left ventricular stroke work index response to exercise had higher ejection fractions than those with an abnormal response (p is less than 0.05). However, 9 patients with normal ejection fractions had an abnormal exercise response. This may reflect loss of left ventricular reserve, abnormal compliance or clinically silent ischemia during exercise. Different indices of left ventricular performance may be widely disparate in coronary artery disease, and abnormalities are frequently apparent only during exercise.
 ...
PMID:A comparison of hemodynamic and angiographic indices of left ventricular performance in patients with coronary artery disease. 65 74

The changes in left ventricular (LV) dynamics induced by brief periods of ischemia (100 seconds) and subsequent reperfusion were analyzed in conscious dogs. Global LV ischemia, induced by partially occluding the left main coronary artery, reduced LV flow homogeneously and impaired LV function as reflected by decreases in LV stroke "work" (89 +/- 4% M +/- SE), systolic shortening (72 +/- 4%), velocity of shortening (56 +/- 6%), LV systolic pressure (34 +/- 5%), and dP/dt (59 +/- 6%). Regional LV ischemia, induced by occluding either the left circumflex or anterior descending coronary artery completely, reduced flow to the ischemic segment (82 +/- 3%) while decreasing segment work (96 +/- 5%), shortening (82 +/- 3%), and velocity of shortening (70 +/- 5%), with minimal depression of overall LV function. In both groups the extent of shortening was reduced more rapidly and greater (P less than 0.01) than shortening velocity. Moreover, with localized ischemia, segment work was reduced more (P less than 0.01) than shortening. With reperfusion, a transient overshoot in function above preischemic control levels was observed in both groups (global work increased by 60 +/- 12% and regional work by 28 +/- 4% above control). This overshoot was not dependent on adrenergic mechanisms, but was prevented by inhibiting reactive hyperemia. Thus myocardial ischemia induces a dissociation between extent and rate of myocardial shortening. A further dissociation between shortening and work is apparent with regional ischemia. After reperfusion there is a transient overshoot in function which appears to be dependent upon the associated reactive hyperemia.
 ...
PMID:Initial myocardial adjustments to brief periods of ischemia and reperfusion in the conscious dog. 65 61

To evaluate the influence of glucose infusate administered with insulin and potassium on left ventricular function during 4 h of ischemia, as well as mechanism of action, four groups of intact anesthetized dogs were studied. Acute regional ischemia was induced with a balloon tip catheter in the left anterior descending artery and infusates were begun after 20 min of ischemia. A threefold increase of plasma glucose concentration was associated with improved left ventricular function during ischemia, compared to animals receiving isovolumic saline. There was a significant decline of left ventricular end-diastolic pressure associated with elevation of stroke volume and ejection fraction to control levels, as determined by indicator dilution. In a separate subgroup studied by cineangiography, shortening of the ischemic anterior wall, after an initial decline, was increased in response to glucose but there was no evidence of extension of injury. Ischemic tissue exhibited a smaller gain of water as well as Na+ per gram dry weight as compared to ischemic controls. On precordial electrocardiogram mapping there was a significant decrease in the sigmaST (sum of ST elevation) as well as NST (number of ST segment elevations), but the reduction of R wave amplitude was not different from controls. To further evaluate long-term effects, eight controls and six treated animals underwent myocardial ischemia and were sacrificed after 4 mo. Calculated area and weight of scar, as well as degree of wall thinning, were similar in both groups. The glucose-treated animals had a significant decrease of plasma FFA in contrast to controls which manifested a significant rise. To examine the postulate that the decrease in FFA was important to therapeutic action, a third group was infused with Intralipid (Cutter Laboratories, Inc., Berkeley, Calif.) and heparin, simultaneously with the glucose infusate, to effect an elevation of plasma FFA during ischemia. Changes in myocardial function and electrolyte composition, as well as precordial electrocardiogram mapping, were similar to that of animals receiving glucose alone. Because serum osmolality was increased approximately 40 mosmol during the glucose infusion, the potential role of hyperosmolality was assessed by infusion of 20% mannitol during acute ischemia in a fourth group. After a transient small increase, there was a moderate decline in function by 4 h, suggesting that the response to glucose is not dependent upon extracellular osmolality. Thus, it is concluded that during the initial hours after the onset of myocardial ischemia the glucose infusate improves ventricular performance without evidence of arrhythmia induction or intensification of ischemic injury. Evolution of irreversible necrosis appears to be delayed rather than prevented under the circumstances of this study.
 ...
PMID:Sustained effect of glucose-insulin-potassium on myocardial performance during regional ischemia. Role of free fatty acid and osmolality. 65 87

The clinical features of 102 cases with transient attacks due to cerebral ischemia were evaluated, and 94 out of 102 cases were followed for an average of 6 years. 1) The clinical study makes comparisons between two groups of patients grouped under the somewhat new definition of Reversible Ischemic Attacks (RIA): classical Transient Ischemic Attacks (TIA) and Stroke with Full Recovery (SFR), in which a complete recovery took place over a longer period, on the average 3 weeks. 2) SFR constitutes the 34.31% of the total cases with transient ischemic episodes. In the carotid district the onset was more frequently gradual in SFR than in TIA and aphasia more frequent in TIA than in SFR. Multiple attacks prevailed in TIA over the SFR group. The definition of transient attack due to ischemia is discussed. 3) Completed strokes occurred in 11 cases (11.7%) with RIA. Hypertension and cardiac disease were significantly frequent in cases with subsequent stroke. The conclusion was reached that TIA is a symptom, not a pathological state, and TIA should be considered an important symptom but not a specific harbinger of completed stroke.
 ...
PMID:Clinical features and long-term follow-up of patients with reversible ischemic attacks (RIA). 69 35

A series of 9 patients have experienced hemisphere and retinal ischemia at an interval after occlusion of appropriate internal carotid arteries. All had radiological evidence of a persisting proximal stump to the occluded artery and, in most, pathological evidence of thrombotic material attached to atheromatous lesions within the stump. Thromboembolism from the stump via the anastomotic supply through ipsilateral common and external carotid arteries is thought to be responsible for the ischemic events to the brain or retina despite absence of flow through the internal carotid artery. Seven of the 9 were treated by surgical excision or obliteration of the stump and, when indicated, common and external carotid endarterectomy. Turbulence in the stump contributed to progressive atherosclerotic changes and probably aggravated thrombogenesis in this location with subsequent embolization into the anastomotic arteries.
Stroke
PMID:"Stump" on internal carotid artery--a source for further cerebral embolic ischemia. 70 25


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