Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0022116 (ischemia)
 91,303 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Nitrates are old drugs, introduced into medical treatment more than 100 years ago, initially as a homeopathic remedy against headache (1850), and only later against angina pectoris (1867). Their typical hemodynamic, antiischemic effects were described in man in the 1950s and 1960s. They include: a reduction in venous return, lowering of the abnormally increased left ventricular enddiastolic pressure during ischemia, a decrease in left ventricular systolic wall stress, and changes in left ventricular geometry resulting in a decrease of myocardial oxygen consumption. The vasodilatory effect on large epicardial coronary arteries, especially on eccentric stenoses through relaxation of vascular smooth muscle tone was described even more recently (1980). This effect proved to be of considerable clinical importance both in angina at rest, that is during a primary increase in vasomotor tone (coronary artery spasm) as well as in angina provoked by exercise, where the increase in vasomotor tone and in the degree of stenosis is often due to a rise in alpha-sympathetic tone. The relaxing effect on the large coronary arteries is regarded as additive to the one on venous tone. The real clinical importance of nitrates became, however, evident only in the last decade with the discovery of EDRF, the so-called endothelial-derived relaxing factor, an endogenous compound of endothelial origin at least partly consisting of nitrous oxide and therefore, like nitrates, it exerts its effect through the stimulation of cGMP. The tendency for coronary arteries to constrict in presence of atherosclerosis is explained by the lack of EDRF, especially in the region of atherosclerotic plaques where the endothelium is often absent or has lost its endocrine function.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:[The mechanism of action of nitrates, 1988 status]. 251 90

Transient global amnesia (TGA) is an unusual form of the amnestic syndrome, clinically characterized by profound disturbance of short-term memory with preservation of immediate recall and long-term memory. Spontaneous recovery is the rule and is usually complete within several hours. The etiology of TGA is not clear. It is considered to be caused by transient ischemia confined to the medial temporal lobe, an area supplied by branches of the vertebrobasilar system. Basilar artery migraine is a well-known syndrome, first described by Bickerstaff. Besides pulsating headache, the dominant symptoms are vertigo, ataxic gait, tinnitus, dysarthria, paraeshesia in the hands, homonymous hemianopsia and sometimes drop-attacks. These symptoms are associated with vertebrobasilar system dysfunction. In this paper, three migraine patients, suffering from one episode of TGA, were reported. All patients were women. Case 1 was a 48-year-old woman with a history of common migraine. Case 2 was a 48-year-old woman with a history of classic migraine. Case 3 was a 59-year-old woman with a common migraine. Family history of migraine exists in case 1 and case 3. Their migrainous attacks began in their twenties and thirties. They suddenly suffered migraine with the symptoms of vertebrobasilar dysfunction. These symptoms are ataxic gait (Case 1, 2, 3), dysarthria (Case 1, 2), vertigo (Case 1, 3) and homonymous hemianopsia (Case 1, 3). Simultaneously three patients had TGA. Duration of retrograde amnesia were about twenty-four hours (Case 1), about thirty minutes (Case 2) and about three hours (Case 3).(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:[Basilar artery migraine associated with transient global amnesia]. 262 11

Eighteen patients suffering from true menstrual migraine and 12 control subjects were studied. We evaluated in different phases of the menstrual cycle and during the migraine crisis the peripheral plasma concentrations of 6-keto-PGF1 alpha (the stable metabolite of PGI2), thromboxane B2 (the stable metabolite of thromboxane A2), PGF2 alpha and PGE2. The mean values of 6-keto-PGF1 alpha in menstrual migraine sufferers are lower than in normal women throughout the whole cycle. The difference between the trends observed in the two groups is statistically significant (p less than 0.05). The plasma levels of TXB2 and of PGF2 alpha are similar in the two groups investigated, both in basal conditions and during the attack. The plasma concentrations of PGE2 are slightly lower in migraineurs in basal conditions than in normals. However, during the crisis they increase significantly (p less than 0.05). In conclusion, among all the parameters considered, PGE2 seems to play the most important role during the pain phase of the attack. The results of the present study suggest that a deficit of PGI2, one of the most important protecting agents against ischemia, might be a typical feature of menstrual migraine and might cause in these patients a vascular hypersensitivity to different ischemic stimuli.
Headache 1989 Apr
PMID:Relevance of prostaglandins in true menstrual migraine. 271 74

This paper contains a review of the signs and symptoms of giant cell arteritis, especially speech and respiratory manifestations of the disease, which are demonstrated by a new case history. An elderly woman presented with speech that was falsetto, breathy, and marked by downward pitch breaks and phonation breaks. In addition, she had visual loss, headache, edema along the scalp and pharyngeal arteries, polymyalgia rheumatica, elevation of Westergren erythrocyte sedimentation rates, and positive arterial biopsy results. Her speech disorder recurred during an exacerbation. A vascular mechanism is proposed to explain her unusual speech, acute recurrence, and rapid recovery. This explanation (reversible ischemia of the laryngeal musculature) has been proposed by other authors in previous studies.
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PMID:Speech pathology in giant cell arteritis. Review and case report. 281 76

Although decreased CBF has now been reported during the prodrome of migraine, the cause of the decreased flow is still unknown. It is particularly unclear whether these phenomena are related to vasospasm and "steal" between the extracranial and intracranial circulation or to the spreading depression of Leao and the accompanying metabolic depression. In the present paper, metabolic changes in the brain during ischemia and reperfusion are reviewed and compared with CNS biochemical changes during migraine attack. In addition, the technique of Topical Magnetic Resonance (TMR) as applied to the in vivo study of energy phosphate metabolism in extracranial tissues and brain is described and the potential of this technique to evaluate shifts in energy metabolism and pH in stroke and migraine is discussed.
Cephalalgia 1985 May
PMID:Biochemical effects of cerebral ischemia: relevance to migraine. 286 8

The present study reports cerebral blood flow (CBF) measurements in 11 patients during attacks of classic migraine (CM)--migraine with aura. In 6 and 7 patients, respectively, cerebral vascular reactivity to increased blood pressure and to hypocapnia was also investigated during the CM attacks. The Xenon-133 intraarterial injection technique was used to measure CBF. In this study, based in part on previously published data, methodological limitations, in particular caused by scattered radiation (Compton scatter), are critically analysed. Based on this analysis and the results of the CBF studies it is concluded: During CM attacks CBF appears to decrease focally in the posterior part of the brain to a level around 20 ml/100 g/min which is consistent with a mild degree of ischemia. Changes of CBF in focal low flow areas are difficult to evaluate accurately with the Xe-133 technique. In most cases true CBF may change 50% or more in the low flow areas without giving rise to significantly measurable changes of CBF. This analysis suggests that the autoregulation response cannot be evaluated in the low flow areas with the technique used while the observations are compatible with the concept that a vasoconstrictive state, unresponsive to hypocapnia, prevails in the low flow areas during CM attacks. The gradual increase in size of the low flow area seen in several cases may be interpreted in two different ways. A spreading process may actually exist. However, due to Compton scatter, a gradual decrease of CBF in a territory that does not increase in size will also appear as a gradually spreading low flow area when studied with the Xe-133 intracarotid technique.
Headache 1989 Jan
PMID:Blood flow and vascular reactivity during attacks of classic migraine--limitations of the Xe-133 intraarterial technique. 201 68

The intracranial pressure, systemic blood pressure and compressed spectral array in EEG monitoring were studied in three patients with typical plateau waves in continuous intracranial pressure recordings. Two patients with brain-tumor and one patient with aqueductal stenosis were included. The intracranial pressure was recorded through an indwelling ventricular catheter attached to a pressure transducer. The systemic blood pressure was recorded through an intraarterial catheter placed in the femoral artery or the dorsalis pedis artery. To obtain continuous and compressed spectral array in the EEG, Berg-Fourier Analyzer by the OET-Biomedica Company of Italy was used. Simultaneous recordings of the intracranial pressure, systemic blood pressure and EEG spectral analysis were made for 180 minutes in each patient. During the plateau waves, the systemic blood pressure did not rise in spite of a marked increase in intracranial pressure, resulting in a marked decrease in the cerebral perfusion pressure. The patients, however, showed no clinical symptoms resulting from ischemia of the brain, such as vasopressor response and impairment of consciousness, but complained only headache. The spectrograms in these patients were characterized by a constant and predominant activity in the alpha or high frequencies. This structural aspect was retained throughout the continuation of plateau waves. The power of low frequencies only appeared transiently. The results suggest that some mechanisms producing and maintaining the fast and/or alpha wave activity may participate in the recurrent appearance of plateau waves.
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PMID:[Brain function in patients with plateau waves studied by compressed spectral array in long-term EEG monitoring]. 300 Apr 13

Vestibular symptoms commonly occur in migraine, and episodic vertigo is most frequently seen. Auditory symptoms also occur, but are less common. When Bickerstaff described basilar artery migraine in 1961, he postulated that the many different symptoms were caused by basilar artery ischemia. He documented that neuro-otologic and other symptoms could occur before or during a migraine headache; others later established that these symptoms could also occur during the headache-free period. Case histories of eleven patients with basilar artery migraine are presented in detail. All met the diagnostic criteria for migraine and experienced vertigo before or during episodic headaches--sometimes with other symptoms of transient brainstem dysfunction. Cases represented both typical and unusual manifestations of migraine with vestibular symptoms: four patients were adolescents, three were more than 45 years old and had previously diagnosed migraine headaches, and four were young adults not previously known to have migraine. Many of the patients were thought to have disorders of the vestibular end organ (sometimes in addition to migraine) and three had undergone previous endolymphatic sac decompressions or perilymph fistula repairs. Diagnostic criteria are reviewed, in order that patients with basilar artery migraine can be distinguished from those with peripheral labyrinthine disease, to allow initiation of appropriate antimigraine therapy and avoidance of unnecessary medical and surgical therapy for end-organ disorders.
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PMID:Episodic vertigo in basilar artery migraine. 310 6

The hemorheologic changes in three groups of patients suffering from acute and chronic cerebrovascular diseases were studied. Firstly, a horizontal study on 57 patients with definite stroke and on 49 patients with TIA was made. Plasma viscosity, whole blood filtration rate, fibrinogen concentration and hematocrit were evaluated as markers of the rheological property of blood. Blood samples were drawn within 6 h from the onset of vascular syndrome. The findings were compared with values obtained in 112 as controls. At the same time, washed red cell filtration rate, together with lactoferrin, betaglucuronidase and beta-thromboglobulin plasma level were assayed. In both groups the onset of the vascular storm was associated with a marked increase of plasma fibrinogen and of blood and plasma viscosity and a significant decrease of whole blood filterability. Lactoferrin, betaglucuronidase and beta-thromboglobulin levels were also significantly increased. Following this, a longitudinal study was performed on 27 patients with definite stroke and 32 patients with TIA. The clinical regression of acute stroke was associated with the progressive reduction of rheological abnormalities. Finally, 81 patients with clinical diagnosis of cerebrovascular disease due to previous stroke or repeated TIA were studied together. An increase of blood viscosity, of fibrinogen concentration and of hematocrit and a decrease of blood filtration rate together with higher levels of beta-thromboglobulin were registered. These results confirm the existence of an association between CVD and hemorheological alterations and suggest more in depth research directed towards identifying the significance of these alterations in the pathogenesis of tissue ischemia.(ABSTRACT TRUNCATED AT 250 WORDS)
Cephalalgia 1985 May
PMID:Hemorheological factors in the pathophysiology of acute and chronic cerebrovascular disease. 316 Apr 74

Careful interpretation of the vascular pathology is important in cases of intestinal ischemia caused by primary mesenteric vein thrombosis because it suggests antithrombin III (AT III) deficiency. This deficiency, an autosomal dominant hereditary disorder, predisposes the patient to venous thrombosis. Similar or acquired deficiencies may also predispose the patient to thrombosis. In hereditary AT III deficiency, 90% of the cases have thrombosis of the leg or iliac veins; 8.3% of the cases, thrombosis of the mesenteric veins. Additionally, some families have a tendency to develop mesenteric vein thrombosis specifically. In this case report, a daughter with probable AT III deficiency had a history of 3 episodes of deep vein thrombosis in the previous 5 years while taking oral contraceptives. Her father, with the same deficiency, died from massive intestinal infarction resulting from portal and mesenteric vein thrombosis. The 19-year old woman developed gradually worsening abdominal pain, signs of peritonitis, and hematemesis. A laparotomy revealed peritonitis that was due to segmental small-bowel infarction; the underlying pathologic condition was mesenteric vein thrombosis. Coagulation study results revealed AT III activity by chromogenic assay, 0.48 u/mL; AT III antigen, 0.5 u/mL; and protein C antigen, 1.15 u/mL. 10 days after discharge, she developed a hemicranial headache with nausea, vomiting, neck tenderness, and photophobia; she was readmitted. A CT scan showed a left posterior parietal cerebral infarct. Repeat AT III activity by chromogenic assay was 0.51 u/mL and AT III antigen level was 0.50 u/mL. Before anticoagulant therapy could be initiated, the patient died 7 days after readmission. The combined lowering of AT III activity and antigen levels to half of normal suggests AT III deficiency. Earlier diagnosis of this deficiency could have been made in light of the patient's own history of thrombosis and the paternal history.
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PMID:Mesenteric venous thrombosis due to antithrombin III deficiency. 333 17


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