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)

The ability of an oxygenated perfluorochemical (Fluosol) to limit myocardial reperfusion injury following global hypothermic ischemic insult was investigated. Neonatal piglet hearts were arrested with cold crystalloid cardioplegia and stored for 12 hours in 2 degrees C saline. Reperfusion was carried out using an isolated, blood-perfused, working heart preparation. Hearts were initially reperfused (10 minutes) with either whole blood (WB, n = 6), unmodified perfluorochemical (PFC, n = 8), or aspartate/glutamate-enriched perfluorochemical cardioplegia (PFC+, n = 6), prior to institution of whole blood perfusion, functional evaluation and left ventricular biopsy. A control group (C, n = 7) was evaluated without an intervening period of ischemia. At a left ventricular diastolic pressure of 9 mm Hg WB hearts developed a left-ventricular stroke work index (SWI) of 3.8 +/- 2.3 x 10(3) erg/g (mean +/- standard error of the mean). Under similar conditions, PFC-reperfused hearts achieved a SWI of 14.6 +/- 1.3 x 10(3), significantly greater than that of WB (p less than 0.001). SWI for PFC+ hearts was 19.8 +/- 1.6 x 10(3), significantly increased over that of PFC (p less than 0.01), and not different from values obtained for C (19.2 +/- 0.8 x 10(3)). In addition, PFC-reperfused hearts demonstrated superior maintenance (p less than 0.05) of ATP (2.08 +/- 0.16 umole/g), compared to WB (1.50 +/- 0.19), while preservation of ATP in PFC+ hearts (2.99 +/- 0.12), was significantly increased over that of PFC (p less than 0.001), and not significantly different from that for C (2.68 +/- 0.17).(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Perfluorochemical reperfusion limits myocardial reperfusion injury after prolonged hypothermic global ischemia. 139 43

On the 60th minute after inducing the acute ischemia in the canine myocardium by the occlusion of the left anterior descending coronary artery, the animals were intravenously infused with perfluorochemical emulsion (PFCE), its salt composition (SC) or 4% surface-active substance (SAS), proxanol, at a dose of 10 ml/kg. Two hours after infusion, the occlusion was removed (reperfusion). The arterial pO2 was maintained at 120 mm Hg. Analysis of the blood flow, oxygen supply, acid-alkali balance, ECG, as well as creatine phosphokinase activity, measured in the ischemic area, has shown that PFC emulsion is capable of reducing ischemic damage and preventing reperfusion-induced myocardium injury. Thus, the presence of perfluorochemicals in the PFC emulsion is an essential factor in its ischemia-protective effect.
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PMID:[The anti-ischemic action of a perfluorocarbon emulsion (PFCE) on the canine myocardium]. 190 59

The effect of perfluorochemical as cardioplegic solution was studied with isolated canine hearts. They were divided into two groups as follows each consisting of ten, and cardioplegia was made every 30 minutes during 3 hours of ischemia. Group I: The solution was oxygenated to PaO2 of 542 +/- 67 mmHg (mean +/- SD). Group II: The solution was deoxygenated to PaO2 of 55 +/- 12 mmHg. Both temperature were 20 degrees C. After 3 hours cardiac arrest, the hearts were fixed to the perfusion unit filled up with the diluted blood. Then hemodynamic and biochemical variables were measured every 30 minutes. There were some significant differences between the groups. Hemodynamic indices especially negative LV max dp/dt were recovered excellently in Group I but not so much in Group II. Negative LV max dp/dt, which was the distinction of the diastole, showed significant difference more than positive LV max dp/dt, which was the distinction of the systole. It was considered that under the same condition, negative LV max dp/dt reflected not only compliance but also preparatory ability of the left ventricle, and it could be one of the important indices evaluating cardiac function. As regarding metabolism, delivery of oxygen with cardioplegic solution was good for the aerobic metabolism also after reperfusion, and in these circumstances, catecholamine was available effectively to the hearts. The conclusion is as follows. It is important for myocardial preservation to suppress the anaerobic metabolism and to keep the circumstances in which catecholamine was available effectively. And oxygenated PFC is good to preserve myocardium and useful as cardioplegic solution.
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PMID:[Experimental study on myocardial preservation with perfluorochemical]. 260 Apr 60

We have previously reported that the combined administration of mannitol and perfluorochemical blood substitutes is evidently effective in protecting the brain from cerebral ischemia. This experimental study was designed to develop more effective method in suppressing brain infarction than the combined treatment of mannitol and PFC. Using the "Canine model of complete ischemic brain regulated with a perfusion method" in which it is possible to control the degree of blood flow to a cerebral hemisphere via a perfusion pump, the effect of eight agents including six kinds as the free radical scavenger on cerebral ischemia was investigated. Eight agents were mannitol, vitamin E (Vit. E), dimethyl sulfoxide (DMSO), vitamin C, glycerol, nizofenone (Y-9179), dexamethasone (Dexa.) and suloctidil (MY-103). After pretreatment with each agent, blood flow was reduced via the pump to 1/10 of the normal state and 1 hour later, return to the normal state was allowed. Subsequent changes in EEG were observed and the effects of the drugs evaluated. In the control group, no recovery of electrical activity was seen, but in six groups among eight treated groups, i.e., treated with mannitol, Vit. E, DMSO, MY-103, Y-9179 and Dexa, gradual emergence of slow waves was observed. And more favorable effects were found when the combined administration of mannitol, Vit. E and Dexa was made in the same experimental schedule as compared with the single administration of each of these drugs. Furthermore in the animals administered with PFC in combination with mannitol, Vit. E and Dexa, flattening of electrical activity could not be seen throughout the period of severe ischemia. Moreover, the power of electrical activity recovered nearly to the preischemic state immediately after recirculation. Although the possible mechanisms are not yet completely clarified, the present results are thought to indicate that this new combination therapy utilizing PFC with mannitol, Vit. E and Dexa may be useful in the treatment of cerebral ischemia.
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PMID:[Experimental study of cerebral protective effect on cerebral ischemia of various antioxidants and other agents. With special reference to the combined treatment of mannitol, vitamin E, dexamethasone and perfluorochemicals]. 632 77

The Hypoxic-Ischemic Encephalopathy (HIE) is a severe illness of the unborn, respectively of the newborn. About 90 percent of the causes occur in utero, about 10 percent after birth. The risk for HIE arises from anatomical and pathophysiological particularities: little overlapping between the great cerebral arteries, poor periventricular vascularisation, and a loss of the autoregulation of cerebral blood flow during asphyxia. Most important is the early detection of intrauterine asphyxia. After birth the general measures include: thermoneutral temperature, oxygenation, normal pCO2, regular blood pressure monitoring, glucose infusion, therapy of convulsions and of an inherent brain edema. After birth the five most common clinical settings in which HIE occurs, are: postpartum asphyxia, PFC, septic shock, pneumothorax and apneas. Therapeutic measures (e.g. volume therapy) have to be prompt but subtle, to prevent ischemia, avoiding overtherapy with its risk of intracranial hemorrhage.
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PMID:[Hypoxic-ischemic encephalopathy. Clinical considerations]. 643 98

Rewarming ischemic injury during vascular anastomosis severely compromises posttransplant pancreas graft survival because the graft has already been subjected to warm and cold ischemia before vascular anastomosis. We examined whether preservation of the pancreas graft by the two-layer method ameliorates rewarming ischemic injury of the graft during vascular anastomosis and also investigated the energy metabolism of the pancreas graft before, during and after rewarming ischemic period. After flushing with cold University of Wisconsin solution (UW), the pancreas grafts were preserved by the two-layer (UW/perfluorochemical [PFC]) method (group 1) or simple cold storage in UW (group 2) for 24-hr and then autotransplanted. In control, the pancreas grafts were flushed out with cold UW and immediately autotransplanted without preservation (group 3). After completion of vascular anastomosis, vascular clamp was not released until 90, 120, or 150 min of rewarming ischemia, including anastomosis time, has elapsed. After 90 min of rewarming ischemia, graft survival rates were 5/5, 100%, 5/5, 100%, and 5/5, 100% in groups 1, 2 and 3, respectively. After 120 min, all the grafts in groups 2 and 3 failed (0/5, 0%, and 0/5, 0%, respectively), however, all the grafts in group 1 survived (5/5, 100%). Even after 150 min, 1 of 3 grafts in group 1 survived (1/3, 33%). After 24 hr preservation, tissue adenosine triphosphate (ATP) and total adenine nucleotides (TAN) levels of the grafts in group 1 were about 2-fold the reference values before harvesting and significantly higher compared with group 2(p < 0.05; p < 0.05). After 120 min of rewarming ischemia, tissue ATP levels in group 1 were 84% of the reference values and significantly higher compared with group 2(p < 0.05). TAN levels of group 1 were also significantly higher compared with group 2(p < 0.05). Two hours after reperfusion, ATP and TAN levels in group 1 were significantly higher than group 2(p < 0.05). There were no remarkable difference between group 1 and group 2 concerning adenosine diphosphate (ADP), adenosine monophosphate (AMP) levels. We conclude that the two-layer (UW/PFC) method ameliorates rewarming ischemic injury of the pancreas graft during vascular anastomosis by increasing tissue ATP concentration and TAN levels during preservation and maintaining tissue ATP and TAN levels during vascular anastomosis. Consequently, ATP levels are rapidly recovered after reperfusion and the graft survives.
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PMID:Amelioration of rewarming ischemic injury of the pancreas graft during vascular anastomosis by increasing tissue ATP contents during preservation by the two-layer cold storage method. 761 35

Leukocyte adherence to the endothelium after ischemia and reperfusion contributes to microvascular injury in most organs. The purpose of this study was to evaluate the leukocyte and endothelial cell adhesion molecules involved with ischemia-reperfusion (I/R)-induced pulmonary microvascular injury in the isolated rat lung. After 45 min of ischemia and 30 min of reperfusion, microvascular permeability was significantly increased and lung retention of leukocytes occurred. Pretreatment with monoclonal antibodies against the leukocyte adhesion molecule CD18 or the endothelial cell adhesion molecules intercellular adhesion molecule 1 and P-selectin significantly attenuated the I/R-induced permeability increase and lung sequestration of neutrophils, mononuclear leukocytes, and eosinophils. In contrast, immunoneutralization of the rat leukocyte adhesion molecule L-selectin neither protected against the I/R-induced permeability increase nor prevented lung sequestration of neutrophils and eosinophils. We conclude that leukocyte adherence in the pulmonary, microvasculature and subsequent permeability increase after I/R is dependent on the integrin CD18, its endothelial cell ligand intercellular adhesion molecule 1, and the endothelial cell rolling factor P-selectin but not the leukocyte rolling factor L-selectin.
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PMID:Adhesion molecules contribute to ischemia and reperfusion-induced injury in the isolated rat lung. 766 25

Rewarming ischemia during implantation severely compromises posttransplant pancreas graft survival because the graft has already been subjected to warm and cold ischemia before implantation. The purpose of this study was to examine whether preservation of the pancreas graft by the two-layer method ameliorates rewarming ischemic injury of the graft during implantation using a canine model. After flushing with cold University of Wisconsin solution (UW), the pancreas grafts were preserved by the two-layer (UW/perfluorochemical [PFC]) method (group 1) or simple cold storage in UW (group 2) for 24 hr and then autotransplanted. In control, the pancreas grafts were flushed out with cold UW and immediately autotransplanted without preservation (group 3). After completion of vascular anastomosis, vascular clamp was not released until 90, 120, or 150 min of rewarming ischemia, including anastomosis time, had elapsed. After 90 min of rewarming ischemia, graft survival rates were 5/5, 100%, 5/5, 100%, and 5/5, 100%, in groups 1, 2, and 3, respectively. After 120 min, all the grafts in groups 2 and 3 failed (0/5, 0%, and 0/5, 0%, respectively); however, all the grafts in group 1 survived (5/5, 100%). Even after 150 min, 1 of 3 grafts in group 1 survived (1/3, 33%). After 24 hr preservation, tissue ATP levels of the grafts in group 1 were about 2-fold the reference values before harvesting (8.23 +/- 0.72 vs. 4.44 +/- 0.49 mumol/g dry weight, P < 0.05) and significantly higher compared with group 2 (8.23 +/- 0.72 vs. 1.76 +/- 0.52 mumol/g dry weight, P < 0.01). After 120 min of rewarming ischemia, tissue ATP levels in group 1 were 84% of the reference values and significantly higher compared with group 2 (3.75 +/- 0.25 vs. 1.57 +/- 0.48 mumol/g dry weight, P < 0.05). Two hours after reperfusion, ATP levels in group 1 were 42% of reference values but significantly higher compared with group 2 (1.86 +/- 0.36 vs. 1.03 +/- 0.18 mumol/g dry weight, P < 0.05). We conclude that the two-layer (UW/PFC) method ameliorates rewarming ischemic injury of the pancreas graft during implantation by increasing tissue ATP contents during preservation and consequently maintaining tissue ATP levels during implantation.
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PMID:Protective effect of preservation of canine pancreas by the two-layer (University of Wisconsin solution/perfluorochemical) method against rewarming ischemic injury during implantation. 814 Jun 27

The purpose of this study was to clarify the role of adenosine in preservation of ischemically damaged pancreas by the two-layer (Euro-Collins solution [EC]/perfluorochemical [PFC]) method using a canine model. Twenty-four-hour preservation of the pancreas graft subjected to 60-min warm ischemia was successful by the two-layer (EC with adenosine/PFC) method (4/5, 80%), but neither simple cold storage in EC (0/5, 0%), nor EC with adenosine (1/5, 20%), nor the two-layer (EC/PFC) method (0/3, 0%) was successful. Tissue ATP concentrations at the end of preservation by the two-layer (EC with adenosine/PFC) method were significantly higher compared with the two-layer (EC/PFC) method (7.23 +/- 2.17 vs. 1.56 +/- 0.40 mumol/g dry weight, P < 0.01). Studies with [2-3H]adenosine demonstrated that only part of adenosine was converted to inosine, hypoxanthine, and adenine, whereas the remainder was incorporated into adenine nucleotides in the pancreas graft. In addition, hypoxanthine, inosine, and adenine did not substitute for adenosine. We conclude that provision of adenosine to ischemically damaged pancreas during preservation by the two-layer (EC/PFC) method allows ATP synthesis within the graft via direct phosphorylation of adenosine. Metabolic processes vital to repair damaged cells and maintain cellular integrity can be maintained, which makes it possible to preserve ischemically damaged pancreas.
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PMID:Role of adenosine in preservation by the two-layer method of ischemically damaged canine pancreas. 816 97

We have demonstrated a direct correlation between a high ATP level in a canine pancreas graft after preservation by the two-layer method and good posttransplant outcome. The purpose of this study was to examine the effect of fasting and exogenous adenosine on the ATP tissue level and viability of the canine pancreas graft during preservation by the two-layer method. Graft viability was judged by graft survival following autotransplantation. Maintenance of normoglycemia for 5 days post-transplant was considered graft survival. The pancreas was harvested from either 72-hr-fated (n = 3) or -fed dogs (n = 4) and preserved by the two-layer (Euro-Collins' solution [EC]/perfluorochemical [PFC]) method for 24 hr. Graft survival rates in fed and fasted groups were 4/4 (100%) and 3/3 (100%), respectively. There was no significant difference in ATP tissue concentrations between the two groups (7.48 +/- 0.55 vs. 7.03 +/- 0.74 mumol/g dry wt, NS). The pancreas was subjected to 60 min warm ischemia and then was preserved by the two-layer method using EC or EC containing 5 mM adenosine for 24 hr. Without adenosine, graft survival rate was 0/3 (0%) and ATP tissue levels were not changed during preservation (1.62 +/- 0.26 vs. 1.56 +/- 0.40 mumol/g dry wt, NS). However, provision of adenosine to the graft during preservation led to the restoration of ATP tissue levels (1.90 +/- 0.54 vs. 8.13 +/- 0.98 mumol/g dry wt, P < 0.01) in 4 of 5 grafts, and these grafts functioned immediately and maintained normoglycemia after transplantation. Graft survival rate was 4/5 (80%). One of 5 grafts, however, did not survive, and the ATP tissue level was not adequately recovered during preservation compared with viable grafts (3.67 vs. 8.13 +/- 0.98 mumol/g dry wt). This study clearly demonstrates that the nutritional state of the donor has no influence on the ATP tissue level and viability of the graft during 24-hr preservation by the two-layer method. On the other hand, provision of adenosine to the graft during preservation stimulates ATP synthesis and improves the viability of the ischemically damaged pancreas.
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PMID:The effect of fasting and exogenous adenosine on ATP tissue concentration and viability of canine pancreas grafts during preservation by the two-layer method. 824 4


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