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)

It has recently been suggested that adenosine is a metabolic coupling factor responsible for an increased cerebral blood flow during hypoxia or increased functional activity. However, tissue adenosine concentrations have been reported to increase in situations previously shown to be unassociated with changes in tissue AMP concentrations. The present experiments were undertaken to assess cerebral cortex concentrations of adenosine under normal circumstances, and to relate changes in adenosine, AMP and cyclic AMP during shortlasting ischemia. Following freezing and extraction of tissue, adenosine was measured using high pressure liquid chromatography. In paralyzed and anaesthetized (70% N2O) rats, freezing of tissue through intact skull bone gave an adenosine concentration of 0.9 +/- 0.1 mumol-kg-1 (mean +/- S.E.M.). With freezing through the exposed dura the concentration was 3 times as high with a large scatter. When special precautions were taken to avoid tissue trauma during craniotomy, the adenosine concentration was 1.1 +/- 0.1 mumol-kg-1. It is concluded that previously reported values are erroneously high. During the first 60 s of total ischemia there was a linear correlation between increase in AMP and in adenosine concentration (as well as between adenosine and cyclic AMP concentrations). It is concluded that increases in tissue adenosine concentration only occur if AMP accumulates. However, since (relative) changes in adenosine concentrations are at least twice those of AMP, analyses of adenosine may provide sensitive measures of a change in phosphorylation state.
Acta Physiol Scand 1977 Sep
PMID:Adenosine in rat cerebral cortex: its determination, normal values, and correlation to AMP and cyclic AMP during shortlasting ischemia. 19 47

To clarify the value of serum enzymes in the detection of intraoperative and postoperative myocardial injury associated with coronary artery bypass grafting, we evaluated 70 consecutive patients (151 grafts). We used electrocardiograms and serial determinations of serum levels: serum glutamic oxaloacetic transaminase (SGOT), creatinine phosphokinase (CPK), lactic dehydrogenase (LDH), and LDH isoenzymes on Days zero, 1, 3, 5, 7, and 10. Patency of all grafts 1 week postoperatively was 92 per cent. Fourteen patients (20 per cent) had ECG evidence of acute myocardial infarction (AMI) or ischemia lasting longer than 48 hours. This incidence of AMI was attendant with no deaths or discernible changes in postoperative ventriculography. LDH-1 (cardiac fraction) was elevated in all patients with myocardial injury. Late elevation of LDH-1 occurred in 2 patients at the time of postoperative catheterization, 1 of whom had negative findings on ECG. Diagnostic correlation was not observed with total LDH, CPK, or SGOT. Predisposing factors to AMI included preinfarction angina (4 of 14 patients), occluded grafts (4 of 14), and a bypass time greater than 120 minutes.
J Thorac Cardiovasc Surg 1975 Sep
PMID:Myocardial injury and bypass grafting. Value of serum enzymes in diagnosis. 24 Sep 85

Fifteen patients were studied to detect unrecognized intraoperative ischemia or necrosis in perioperative myocardial infarction (MI) associated with coronary bypass. Simultaneous arterial and coronary sinus blood samples were analyzed for lactate and both total and MB-CPK. Coronary sinus flow measurements were done coincident with sampling in seven patients. Five had perioperative MI diagnosed by positive pyrophosphate scan and electrocardiogram. Although normal initially (mean 19 +/- 5.0%), lactate extraction after thoracotomy, before aortic cross-clamping, became abnormal in 12 patients with more pronounced abnormality in those with perioperative MI (-19 +/- 9.0%). Net efflux of lactate was higher in perioperative MI (mean 0.6 +/- 0.2 vs 0.016 +/- 0.04 mM/L) than in non-MI patients. All patients had detectable total and MB-CPK (mean 295 and 31 IU/L, respectively) and all those with coronary disease had a positive arterial-coronary sinus gradient for MB-CPK (mean 9 IU/L). Perioperative MI patients had a higher gradient than non-MI patients (mean 25 vs 2 IU/L) and with one exception that gradient exceeded 5-7 IU/L. It is concluded that severe ischemia before aortic cross-clamping precedes perioperative MI and may contribute to release of CPK into coronary sinus blood. Improvement in the techniques of anesthesia and intraoperative myocardial preservation are suggested.
Circulation 1977 Sep
PMID:Coronary sinus blood flow and sampling for detection of unrecognized myocardial ischemia and injury. 30 99

The relationship between long-term propranolol hydrochloride therapy and subsequent coronary bypass operation was prospectively investigated in 119 patients who were grouped three ways: propranolol therapy continued in full dosage to operation (group A), propranolol therapy discontinued or tapered 24 to 72 hours preoperatively (group B), and no preoperative propranolol therapy (control group). During preoperative hospitalization, one patient in each group A and the control group suffered an increase in anginal symptoms compared with 15 patients in group B, three of whom also had new ventricular arrhythmias. During anesthesia up to the period of cardiopulmonary bypass, 26% of group A patients showed signs of ischemia (eg, ST segment deviation or ventricular arrhythmias) as compared with 51% of the control group and 70% of group B. Hypotension and bradycardia were not more common in group A patients. No differences among groups were noted in case of emergence from bypass, need for cardiac stimulants, or mortality.
JAMA 1978 Sep 29
PMID:Preoperative propranolol therapy and aortocoronary bypass operation. 30 9

A comparison of the effectiveness of two renal preservation techniques was studied in 30 cannine renal pairs. In the absence of warm ischemia, 24-hr preservation by pulsatile perfusion was not significantly superior to hypothermic storage. When 15 min of warm ischemia was added as an additional insult, pulsatile perfusion afforded significantly better early function than cold storage. Combinations of pulsatile perfusion and hypothermic storage following 15 min of warm ischemia were superior to hypothermic storage alone, but inferior to pulsatile perfusion. Kidneys initially perfused for 6 hr and then cold-stored functioned slightly better than kidneys perfused for 18 hr after initial cold storage.
Transplant Proc 1977 Sep
PMID:Twenty-four hour canine renal preservation by pulsatile perfusion, hypothermic storage, and combinations of the two methods. 33 87

Evidence is mounting that three drugs that inhibit platelet function--aspirin, dipyridamole, and sulfinpyrazine--have an antithrombotic effect in humans. Particularly in men, aspirin is beneficial in controlling transient ischemic attacks and stroke, and there is evidence that it may be effective in preventing thrombotic and embolic complication of hip surgery. It abolishes symptoms in peripheral ischemia associated with thrombocytosis and spontaneous platelet aggregation and may prove effective in coronary artery disease. When combined with oral anticoagulants, aspirin is more effective than oral anticoagulants alone in preventing systemic embolism in patients with prosthetic heart valves. Dipyridamole in combination with oral anticoagulants reduces the incidence of systemic embolism after prosthetic heart valve replacement. Sulfinpyrazone reduces the incidence of sudden death in the first year after myocardial infarction, decreases the incidence of arteriovenous shunt thrombosis in patients undergoing chronic hemodialysis, and when combined with anticoagulants, may be effective in reducing the frequency of episodes in recurrent venous thrombosis.
Postgrad Med 1979 Sep
PMID:Antiplatelet drugs in thromboembolism. 38 46

A randomized, single-blind trial of repeated intravenous infusion of Brinase was carried out in 70 petients with severe chronic limb ischemia, who were candidates for lumbar sympathectomy or amputation. The enzyme caused s significant increase in calf and ankle pressure index. At six months follow-up, the clinical results were statistically significant in favour of Brinase when all patients were considered, but not if 10 patients with Buerger's disease were omitted from the analysis. Patients treated with a combination of Brinase and coumarins had a better clinical outcome than patients receiving either treatment on its own.
Eur J Clin Pharmacol 1979 Sep
PMID:Clinical trial of brinase and anticoagulants as a method of treatment for advanced limb ischemia. 38 20

Laser photocoagulation has changed the visual prognosis of diabetic patients affected by retinopathy. It aims to lower the risk of blindness of diabetic patients. The goal of photocoagulation is to reduce the tissue damage of microangiopathic origin expressed by nonperfusion areas and permeability abnormalities that are responsible for retinal ischemia and oedema respectively. Loss of visual acuity in the diabetic is due mainly to two causes : first, vitreous hemorrhage with its dramatic loss of vision; secondly, macular cystoid oedema, occuring more commonly and with progressive loss of central vision. The efficiency of pan-retinal photocoagulation in reducing the risk of vitreous hemorrhage and consequent blindness in patients with disc or preretinal newly formed vessels, has been ascertained by American and British randomised studies. The indications, technics and results of photocoagulation in non-proliferative diabetic retinopathy are the subject of many studies. Only photocoagulation for macular oedema due to intra-retinal microvascular abnormality has shown to be of benefit.
Diabete Metab 1979 Sep
PMID:[Treatment of diabetic retinopathy with laser photocoagulation (author's transl)]. 38 89

It is important to establish the diagnosis of temporal arteritis because the disease is treatable; treatment may prevent blindness and even death. Temporal arteritis usually occurs in people older than 51 years of age, although very rarely, histologically documented disease occurs in younger people. The onset may be occult, so that there are few findings. A multitude of signs and symptoms may occur such as fever, headaches, malaise, weight loss, anemia, stroke, cranial nerve palsies, polymyalgia rheumatica, aortitis and other large vessel involvement. The eye may suffer from ischemic optic neuropathy (anterior or posterior), central or cilio-retinal arterial occlusion, ophthalmic artery ischemia, or extraocular muscle palsies. An arterial biopsy showing giant cell arteritis establishes the diagnosis. However, a negative biopsy does not rule out the disease because of the occasional presence of skip areas. Arteriography has only rarely yielded a positive temporal artery biopsy when the initial biopsy done elsewhere was negative. As a diagnostic parameter, the erythrocyte sedimentation rate is nonspecific, being elevated in diseases other than temporal arteritis and sometimes being falsely lowered by technical factors. Furthermore, the temporal artery biopsy is occasionally positive despite a normal erythrocyte sedimentation rate. Treatment is aimed at relieving the patient's symptoms and normalizing the erythrocyte sedimentation rate. Because of the wide spectrum of clinical and laboratory finding in temporal arteritis, no one specific treatment regimen with systemic corticosteroids works for all patients. Temporal arteritis is a well known disease of the elderly which ir rarely fatal but results in significant visual morbidity (Hinzpeter & Naumann, 1976; Spencer & Hoyt, 1960). Since Hutchinson's (1890) description, more than a thousand articles have been written on the subject (Cohen & Smith, 1974). Despite this, many unanswered questions and controversies remain concerning the diagnosis, prognosis and treatment of temporal arteritis. My goal is to review these questions and areas of controversy.
Doc Ophthalmol 1979 Sep 17
PMID:Controversies regarding giant cell (temporal, cranial) arteritis. 39 20

The exposed left superior frontal gyrus of the anesthetized macaque brain was focally traumatized by a jet of compressed air. Focal blood flow in tissue around the lesion and total cerebral blood flow was determined before and during the 4 hours after trauma by the hydrogen clearance technique. Blood flow fell in tissue adjacent to the injured brain but the reduction was not statistically significant. Total cerebral blood flow, blood flow in the right superior-frontal gyrus, and oxygen consumption of the brain was unaffected by the trauma. The authors conclude that neither spreading ischemia within uninjured tissue surrounding focally traumatized brain nor posttraumatic diaschisis is readily provoked in the anesthetized brain of the monkey.
J Neurosurg 1977 Sep
PMID:Blood flow and oxygen consumption of the focally traumatized monkey brain. 40 66


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