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Biomedical subjects

S F Katircioğlu

Publications and source records attributed to S F Katircioğlu.

At least 19 recordsLinked to original sources
PubMed2000

Prevention of intimal hyperplasia by single-dose pre-insertion external radiation in canine-vein interposition grafts.

OBJECTIVES: to evaluate the efficacy of single-dose pre-insertion gamma radiation of vein grafts in the prevention of intimal hyperplasia. METHODS: femoral artery interposition grafts with internal jugular vein were inserted in 12 mongrel dogs. The animals were randomly divided into two groups. Immediately before graft replacement, jugular veins were treated with a single dose of cobalt-60 radiation at 14 Gy or received no radiation (control group). Six weeks after graft insertion, the vein grafts were pressure-perfusion fixed and harvested for the histomorphometric analysis. Quantitative data on anastomotic stenosis were calculated from Gilman parameters after cross-sectional image analysis. RESULTS: vein grafts treated with radiation demonstrated significantly decreased neointima formation compared with grafts in the control group. The mean Gilman parameter for the control group was 1.09 S.E.M. 0.34 mm and for the radiotherapy group was 0.65 S.E. M. 0.23 mm (p<0.05). All vein grafts in the radiotherapy group had a decreased amount of intimal and cellular infiltration. CONCLUSION: single-dose external pre-insertion gamma radiation of vein grafts reduced the amount of intimal hyperplasia in this animal model.

Animals↗
PubMed2000

Beneficial effects of iloprost during experimentally induced hemorrhagic shock.

BACKGROUND: The aim of the study was to evaluate the efficacy of iloprost on myocardial insufficiency associated with hypovolemic shock in dogs. We designed the study as a controlled randomized study. METHODS: Sixteen mixed-breed dogs were included into the study and divided into two equal groups as the control and iloprost groups. Mean arterial pressure was reduced to 45 mmHg by withdrawing the arterial blood into citrated bags. The control group did not receive any drug but the other group received iloprost at a rate of 20 ng/kg/min by an infusion pump. Iloprost infusion was started 30 min after the blood pressure was reduced to 45 mmHg. All measurements were made before removal of blood, 45 min after exsanguination and at 1 hour intervals for 3 hours. Left ventricular stroke work index was measured 72 hours after the study. The hemodynamic and biochemical parameters and blood gas analysis were obtained. RESULTS: After hemorrhage, cardiac index (CI) decreased significantly from 132 +/- 14 to 51 +/- 8 ml/kg/min in the control group and from 128 +/- 11 ml/kg/min to 47 +/- 13 ml/kg/min in the iloprost group, respectively but at the end of the third hour it was 81 +/- 8 ml/kg/min in the control group and 105 +/- 6 ml/kg/min in the iloprost group (p < 0.05). Tumor necrosis factor-alpha (TNF alpha) was 41 +/- 8 pg/ml in the control group and 18 +/- 6 in the iloprost group 3 hours after bleeding (p < 0.05). Tumor necrosis factor-alpha concentration was significantly higher in the control group than in the iloprost group. There was no significant difference in pH between the groups but actual bicarbonate concentrations were different between the groups (p < 0.05). At the end of the third hour total body oxygen consumption was 105 +/- 11 ml/min in the control group and 132 +/- 12 ml/min in the iloprost group (p < 0.05). Oxygen delivery 3 hours after hemorrhage was 201 +/- 19 ml/min in the control group and 252 +/- 24 ml/min in the iloprost group (p > 0.05). Left ventricular stroke work index was higher in the iloprost group (p < 0.05). CONCLUSIONS: Hemorrhagic shock causes tumor necrosis factor-alpha release which may lead to multiple organ failure. Organ dysfunction still persists even after the appropriate treatment. Iloprost attenuates the release of tumor necrosis factor-alpha which may improve the adverse effects of hemorrhagic shock.

Animals↗
PubMed2000

ATP-MgCl2 treatment after experimental acute myocardial ischemia and reperfusion.

BACKGROUND: The effect of ATP-MgCl2 on myocardial metabolism and hemodynamics was investigated in this study. METHODS: Twelve dogs were entered in this research. Six dogs received ATP-MgCl2 and the remaining dogs were considered as controls. The amount of ATP and MgCl2 concentration of this solution is 100 mumol/ml each. The volume administered to the animals during the aortic occlusion is 0.25 ml/kg/hour; in the solution are 100 mumol/ml dose each. The volume administered to the animals during reperfusion is 0.25 ml/kg/hour. The left anterior descending artery was occluded for a period of one hour and the drug was administered during reperfusion. RESULTS: Three hours after reperfusion, cardiac output was 1524 +/- 26 ml/min in the control group and 1638 +/- 47 ml/min in the ATP-MgCl2 group (p < 0.05), pulmonary capillary wedge pressure was 14 +/- 3 in the control group and 8 +/- 2 in the ATP-MgCl2 group. At the same time interval tissue ATP and lactate level was 7 +/- 3, 1.3 +/- 0.4 in the control group and 14 +/- 2, 0.0 +/- 0.2 in the ATP-MgCl2 group respectively (p < 0.05). CONCLUSIONS: In this study we demonstrated that ATP-MgCl2 usage after one hour of arterial occlusion protects the heart from the adverse effects of ischemia/reperfusion.

Adenosine Triphosphate↗
PubMed2000

Preservation of myocardial functions by pentoxyphylline cardioplegia during and after cardiopulmonary bypass.

BACKGROUND: The aim of the presented study was to evaluate the preservation effect of the pentoxyphylline-blood cardioplegia on myocardial functions during and after the cardiopulmonary bypass in an experimental dog model. METHODS: Central hemodynamics and metabolic variables such as creatine phosphokinase, myocardial oxygen extraction and myocardial lactate extraction were obtained during and following 4 hours after the cardiopulmonary bypass after the baseline scores were recorded. Twelve mongrel dogs were divided into two equal groups. The first group of animals served as controls. The second group of animals was treated with pentoxyphylline cardioplegia that was added to each blood cardioplegia as 15 mg/100 ml. RESULTS: After bypass, the hemodynamic parameters were better in the pentoxyphylline group. Cardiac index fell in all animals, but it was significantly less in the control group. Pulmonary capillary wedge pressure was lower in the pentoxyphylline group as an index of better preservation of ventricular filling pressure. CPK-MB was significantly higher in the control group both at 2 and 4 hours after the bypass. It was 79 +/- 13 iu/L in the control group and 41 +/- 9 iu/L in the pentoxyphylline group 4 hours after cardiopulmonary bypass. MLE was also higher both on bypass and following bypass in the control group. CONCLUSIONS: In conclusion, pentoxyphylline usage may reduce the risks of ischemic-reperfusion injury during and following cardiopulmonary bypass and aortic cross-clamping. It can be an administered drug during cardioplegia.

Animals↗
PubMed1999

Comparison of reoperation findings of the Carpentier-Edwards (standard) bioprosthesis and the St Jude bioimplant (formerly Liotta) in the mitral position.

Between 1986 and 1996, 50 patients with Carpentier-Edwards porcine bioprostheses and 211 with a St Jude bioprosthesis underwent reoperation because of structural valve deterioration. Structural valve deterioration was defined as an intrinsic abnormality of the prosthesis (leaflet disruption, calcification, leaflet thickening, etc.) that caused stenosis or regurgitation found on physical examination and echocardiography. Fifteen of the Carpentier-Edwards bioprosthesis group were male and 35 were female. Eighty-two of the St Jude group were male and 129 female. The mean age at reoperation was 33.88 +/- 10.31 years (range 19-70) for the Carpentier-Edwards group and 39.03 +/- 9.97 years (range 20-70) for the St Jude group. The average duration was 94.32 +/- 3.83 months for the Carpentier-Edwards group and 73.76 +/- 1.44 months for the St Jude group (P < 0.001). The mean aortic cross-clamp time was 67.4 min (minimum 32, maximum 210) for the St Jude group and 63.21 min (minimum 36, maximum 230) for the Carpentier-Edwards group. Reoperative hospital mortality was 10% (5/50) in the Carpentier-Edwards group and 7.1% (15/211) in the St Jude group (P > 0.05). Late failure modes of the bioprostheses were defined for the purposes of this study as calcification, stenosis and torn leaflets. Of the Carpentier-Edwards group, seven patients (14%) developed calcification, six patients (12%) developed stenosis and 13 patients (26%) developed leaflet tears. Of the St Jude group, the incidences were 22 patients (10%), 67 patients (31.8%) and 87 patients (41%), respectively. This study indicates that the Carpentier-Edwards bioprosthesis is more durable than the St Jude. The St Jude bioprosthesis tended to develop leaflet tears and linear calcification in female patients, and nodular calcification in male patients.

Adult↗
PubMed1999

Experimental inhibition of protamine cardiotoxicity by prostacyclin.

Twelve animals (26+/-5 kg) were subjected to the study. In this experimental study, the authors used prostacyclin to inhibit the toxic metabolite release during protamine administration. Animals were divided into two equal groups. Six animals received prostacyclin (the prostacyclin group), and the other six animals did not receive any additional treatment (the control group). All cardiac output and biochemical measurements were evaluated at baseline; before cardiopulmonary bypass; and at 5, 30, and 60 minutes after protamine administration. The measured cardiac index showed that the hearts treated with prostacyclin had satisfactory preservation of left ventricular function. Metabolic and biochemical data showed that the tumor necrosis factor level was raised significantly in the control group (20.75+/-2.2 in the control group and 13.75+/-2.5 pg/mL in the prostacyclin group). Also, E and P selectin levels were elevated in the control group, but this change was less marked in the prostacyclin group. In addition, the intracellular adhesion molecule-1 (ICAM-1) level was significantly higher in the control group than in the prostacyclin group (9.26+/-2.13 in the control group and 5.13+/-1.66 ng/mL in the prostacyclin group). The authors observed that prostacyclin inhibited the toxic mediator release during heparin reversal with protamine. This inhibition is one way of protecting the myocardium reserves from protamine cardiotoxicity.

Animals↗
PubMed1999

Coronary sinus retroperfusion during acute experimental coronary artery occlusion.

BACKGROUND: This study was planned to show the effect of retroperfusion and cardiopulmonary bypass on myocardial hemodynamic recovery. METHODS: Eighteen dogs entered this study. After, left anterior descending artery (LAD) was dissected and occluded, the animals were divided into three equal groups; Group I: retrograde coronary sinus perfusion, group II: cardiopulmonary bypass and retrograde coronary sinus perfusion, Group III: control group, left anterior descending artery occlusion only. RESULTS: In Group III, deterioration of the hemodynamic values progressed parallel with the degree of ischemic damage but in Group I, hemodynamic parameters were better because of the retrograde coronary sinus perfusion and minimally affected by the reperfusion. In Group II, at the end of the cardiopulmonary bypass minimal myocardial damage was observed. CONCLUSIONS: There is no statistical difference between Group I and II if we examine the data that was taken after reperfusion although myocardial performance was better in Group II.

Animals↗
PubMed1999

Effects of ATP-MgCl2 administration in hypovolemic dogs.

BACKGROUND: The aim of the study was to evaluate the efficacy of ATP-MgCl2 on myocardial insufficiency associated with hypovolemic shock in dogs. We designed the study as a controlled randomized study. METHODS: Six mixed-breed dogs weighing 22 +/- 3 kg were included in the control group and 20 +/- 3 kg in the ATP-MgCl2 group. After the animals were anesthetized 40 ml/kg of blood was withdrawn in 15 minutes. Animals were observed for 45 minutes after removal of blood. Six animals received 45 ml/kg of lactated Ringer's solution and the other animals were treated with 45 ml/kg of lactated Ringer's solution and ATP-MgCl2. All measurements were made before removal of blood, 45 min after exsanguination and at 1 hour intervals for 3 hours. The following parameters were measured; systemic and pulmonary arterial pressures, pulmonary capillary wedge pressure, central venous pressure, cardiac output, rectal temperature, arterial pH, PCO2 and PO2 and mixed venous hemoglobin oxygen saturation. In addition blood samples were collected for the analysis of lactate and tumor necrosis factor (TNF) concentrations. RESULTS: After hemorrhage, cardiac index (CI) decreased significantly from 122 +/- 9 to 52 +/- 9 ml/kg/min in the control group (p < 0.0001) and from 124 +/- 11 ml/kg/min to 50 +/- 6 ml/kg/min in the ATP-MgCl2 group, respectively (p < 0.0001). After volume replacement, Cl was 93 +/- 6 ml/kg/min in the control group and 111 +/- 4 ml/kg/min in the ATP-MgCl2 group 3 hours after the onset of reinfusion, respectively (p < 0.05). TNF was 36 +/- 5 pg/ml in the control group and 21 +/- 3 pg/ml in the ATP-MgCl2 group (p < 0.05). Three hours after the onset of hemorrhagic shock, oxygen consumption and delivery were 126 +/- 14 and 206 +/- 19 ml/min in the control group and 198 +/- 16 and 305 +/- 27 ml/min in the ATP-MgCl2 group, respectively. At the same time point the oxygen extraction ratio was 0.49 +/- 0.04 in the control group and 0.61 +/- 0.03 in the ATP-MgCl2 group (p < 0.01). CONCLUSIONS: Hemorrhagic shock causes TNF release which may cause multiple organ failure. Organ dysfunction still persists even after the appropriate treatment. ATP-MgCl2 attenuates the release of TNF which may improve the adverse effects of hemorrhagic shock.

Adenosine Triphosphate↗
PubMed1998

Iloprost added to the cardioplegic solutions improves myocardial performance.

A total of 12 mongrel dogs were divided into two equal groups. Six animals received IIoprost and the other 6 animals did not receive any additional treatment. In the Iloprost group, Iloprost was added to the cardioplegic solution (25 ng). Also, Iloprost was used (10 ng/kg/min.) 5 min. before and after cross-clamping. All cardiac output and biochemical measurements were evaluated before cross-clamp and 15 min., 1 h, and 4 h after cross-clamp. The measured dp/dt shows that the hearts treated with Iloprost preserved left ventricular function. Comparison of contractility indices between the groups revealed that contractile recovery was 59% in the control group and 71% in the Iloprost group (p < 0.05). Tumor necrosis factor (TNF) alpha level was significantly elevated in the control group (p < 0.001). Its level was 22.2 +/- 2.2 pg/mL in the control group and 13.8 +/- 1.0 pg/mL in the Iloprost group. E- and P-selectin levels were elevated in the control group (p < 0.001). ICAM-1 level was also elevated in the control group. ICAM-1 level was 17.7 +/- 1.8 ng/mL in the control group and 8.5 +/- 1.8 ng/mL in the Iloprost group. The Iloprost that was added to the cardioplegic solution and low dose administration during the pre- and post-ischemic period inhibits the toxic mediator release from endothelium-leukocyte interaction and reduces the severity of ischemia-reperfusion injury.

Adenosine Diphosphate↗
PubMed1998

Preservation of myocardial metabolism in acute coronary artery occlusions with retrograde coronary sinus perfusion and iloprost.

A total of 12 healthy mongrel dogs were subjected to the study. The left anterior descending artery was occluded. The occlusion was done for 15 min. At the end of this period, without removing the occlusion, the heart was retroperfused for 3 h. Then, occlusion was removed and reperfusion was supplied. Animals were divided into two equal groups. Six animals received iloprost and the other six control did not receive any additional treatment. In the iloprost group, the drug was administered into the coronary sinus. After 15 min following occlusion, iloprost was infused at a rate of 50 microg/min continuously. Cardiac output (CO), mean arterial pressure (MAP), mean pulmonary arterial pressure (MPAP), heart rate (HR), pulmonary capillary wedge pressure (PCWP), right atrium pressure (RAP), myocardial oxygen extraction (MOE) and myocardial lactate extraction (MLE) parameters were examined in the two groups, before and during retroperfusion and during the reperfusion (1-4 h). Iloprost retroperfusion (50 microg/min) was started at the fifteenth minute of occlusion and continued till the end of the observation period (3 h). The measured hemodynamic data showed that the hearts treated with iloprost had satisfactory preservation of cardiac function. At the end of the reperfusion period cardiac output was 1.5 +/- 0.06 L/min in the control and 1.7 +/- 0.04 L/min in the iloprost group (P < 0.05). At the end of the reperfusion period, tumor necrosis factor level was raised significantly in the control group (P < 0.05). Myocardial lactate release was also high in the control group (P < 0.05). CPK-MB release was low in the iloprost group (P < 0.05). We conclude that retrogradely administered iloprost reduced the risk of myocardial injury and it is probable that this drug effectively distributes to the area of myocardium at risk.

Animals↗
PubMed1998

Simplified retroperfusion system preserves the myocardial function during acute coronary artery occlusion.

It is known that coronary venous retroperfusion restores the blood flow to the ischemic myocardium, resulting in reduction of infarct size and improvement in left-ventricular pump function. In this study, we used an animal model to investigate the effects of a simplified coronary venous retroperfusion system on myocardial hemodynamics. Twenty dogs were entered in this study. All dogs underwent fifteen minutes occlusion of the left anterior descending artery. For the rest of the experiment the dogs were randomized into two groups: the control group (n = 10) underwent a further 2 hours left anterior descending artery occlusion, then clamps were released and the animals were observed for 6 hours. In the retroperfusion group (n = 10) a simple aortocoronary sinus connection was made and retrograde perfusion achieved with an outflow of 43 +/- 6 ml/min. Retrograde coronary sinus perfusion was maintained for three hours and then the dogs were observed for six hours. Tissue adenosine triphosphate levels were 6 +/- 3 mumol/g in the control group and 12 +/- 2 mumol/g in the retroperfusion group (p < 0.05) 6 hours after reperfusion. Creatine phosphokinase levels were 99 +/- 11 IU/L in the control group and 42 +/- 8 IU/L in the retroperfusion group 6 hours after reperfusion (p < 0.05). Cardiac index was 63 +/- 4 ml/kg/min in the control group and 79 +/- 2 ml/kg/min in the retroperfusion group 6 hours after retroperfusion (p < 0.05). Left-ventricular stroke-work index at a pulmonary capillary artery wedge pressure of 20 mmHg was 0.54 +/- 0.06 g.m/kg in the retroperfusion group and 0.29 +/- 0.03 g.m/kg in the control group 6 hours after reperfusion (p < 0.05). It is concluded that myocardial hemodynamic and biochemical function can be preserved by simplified coronary sinus retroperfusion.

Animals↗
PubMed1996

Spinal cord protection with the use of prostacyclin during aortic occlusion.

This study was planned to investigate if prostacyclin (PGI2) would reduce spinal cord injury following aortic occlusion. Twelve dogs underwent 90 min of aortic occlusion. Six dogs received PGI2 and the remaining animals did not. PGI2 was administered at a dose of 25 ng/kg/min during occlusion of the aorta. There were five paraplegic animals in the control group and one in the PGI2 group 72 hr after aortic occlusion. Neurological recovery was better in the PGI2 group than in the control group (P < 0.05). Malondialdehyde level was 3.55 +/- 0.58 nmole/ml in the PGI2 group and 6.35 +/- 1.27 nmole/ml in the control group 60 min after aortic cross-clamp removal (P < 0.05). At the same time interval, protein thiol groups were 629 +/- 50 micromole/L in the PGI2 group and 376 +/- 69 micromole/L in the control group (P < 0.05). Distal arterial pressure and central venous pressure were 15 +/- 4 and 12 +/- 3 mm Hg in the control group and 33 +/- 5 and 7 +/- 1.6 mm Hg in the PGI2 group, respectively (P < 0.05). In this study exogenously administered PGI2 protected the spinal cord from the hazardous effects of aortic occlusion lasting 90 min.

Animals↗
PubMed1996

Enoximone usage for experimental spinal cord protection during aortic cross-clamping.

Spinal cord preservation during aortic cross-clamping is of vital importance. Maintenance of spinal cord blood supply is one of the key points for spinal cord preservation. In this study enoximone was selected as an agent to reduce the risk of spinal cord injury because of its inotropic and vasodilator actions. Ten dogs underwent sixty minutes aortic occlusion. Five animals received enoximone and the others did not (the control group). Enoximone dosage was 10 microgram/kg/min. Four dogs in the control group suffered paraplegia. There were no paraplegic events in the enoximone group. Cerebrospinal fluid pressure was 17 +/- 3 mmHg in the control group, 15 +/- 4 mmHg in the enoxirmone group. Distal aortic pressure was 15 +/- 4 mmHg in the control group, 47 +/- 6 in the enoximone group (p < 0.001). In this study we conclude that enoximone is an effective agent to reduce the risk of spinal cord injury.

Animals↗
PubMed1995

Beneficial effects of prostacyclin treatment on reperfusion of the myocardium.

A total of 20 patients with coronary artery disease were studied in order to assess the benefits of prostacyclin administration on reperfusion of the ischaemic myocardium after cardiopulmonary bypass. Ten received prostacyclin (25 ng/kg per min) while ten were untreated controls. There was no difference between groups with regard to age, preoperative ejection fraction and aortic cross-clamping times. There were no in-hospital deaths in either group. The administration of prostacyclin significantly altered the metabolic side effects of reperfusion followed by hypothermic cardioplegic arrest. Myocardial oxygen consumption after cardiopulmonary bypass was significantly higher in the prostacyclin-treated group than in controls (18.5 ml versus 13 ml; P < 0.01). Prostacyclin treatment significantly reduced the leucocyte activity: leukotriene B4 concentrations were 58 pmol/l in prostacyclin-treated patients compared with 93 pmol/l in controls (P < 0.01). Such recovery of metabolic status during reperfusion resulted in better haemodynamic function in patients receiving prostacyclin.

Coronary Artery Bypass↗