Effects of dexmedetomidine and thymoquinone on erythrocyte deformability in lower limb ischemia reperfusion injury in streptozotocin-induced diabetic rats.

OBJECTIVE: In this study we aimed to evaluate the effect of dexmedetomidine and thymoquinone on erythrocyte deformability in lower limb ischaemia-reperfusion (IR) injury in streptozotocin-induced diabetic rats. MATERIAL AND METHODS: Thirty Wistar albino rats were equally divided into 5 groups (n = 6); randomized control group (Group C), diabetes control group (Group DC), DIR group (Group DIR), DIR group with thymoquinone 25 mg.kg‒1 intraperitoneally (Group DIRT) and Group DIR with dexmedetomidine 100 µg.kg‒1 intraperitoneally (Group DIRD). Erythrocyte packs were prepared from heparinized blood samples and deformability measurements were performed. RESULTS: IR significantly increased the relative resistance, a marker of erythrocyte deformability when compared to control group (p < 0.05). There were significant differences among the groups in comparisons with ANOVA test (p < 0.0001). Comparisons of the groups DIRD and DIRT revealed similar results (p = 0.824). The values of Group DIR were significantly higher than those of the control, DC, DIRD and DIRT groups (p < 0.0001, p = 0.001, p = 0.004, p = 0.002, respectively). The values of the DC, DIR, DIRD and DIRT groups were significantly higher than those of the control group (p < 0.0001, all). CONCLUSION: Erythrocyte deformability may cause more problems in microcirculation. Dexmedetomidine and thymoquinone may be useful in reducing the adverse effects of this type of injury (Fig. 1, Ref. 41).

Investigating the effects of two different pump heads (Centrifugal vs. Roller Pump) on hematological and immunological mechanisms.

BACKGROUND AND AIM: Technological developments and enhancement of knowledge level enable heart surgery with low mortality rates in most centers. On the other hand, increased systemic inflammatory response against cardiopulmonary bypass (CPB) plays a critical role in the development of postoperative complications. We aimed to compare the effects of centrifugal pump where it is claimed that blood is exposed to minimal trauma and roller pump techniques on inflammatory response and oxidant status during CPB. MATERIALS AND METHODS: : A total of 40 patients, who had coronary artery disease and underwent coronary artery bypass graft (CABG) surgery using either roller or centrifugal pump between June 2012 and June 2013 were enrolled in this study. Patients over 40 years old and without any known immunologic, infectious, or inflammatory incidents and hematological problems for the past 6 months were included in the study. Two study groups (Group R: roller pump group and Group C: centrifugal pump group) were created. During CABG surgery tumor necrosis factor (TNF) alpha, interleukin (IL)-6, IL-8, superoxide dismutase (SOD), catalase (CAT), and nitric oxide levels were measured before and after CPB. RESULTS: TNF alpha, IL-6, and IL-8 levels measured before and after CPB were found to be similar between groups. SOD, CAT and Nitric oxide levels were also similar between groups. After the CPB period, glutathione peroxidase enzyme activities in Group R measured after CPB were significantly lower than those measured in Group C. The platelet-activating factor (PAF) levels before CPB usage period were same in both groups, where PAF levels after CPB were found to be significantly higher in roller pump group than centrifugal pump group. At inter-group comparisons, the levels of PAF were same at each group before and after CPB. CONCLUSION: The study findings indicate that usage of the centrifugal pump does not have a clear superiority in terms of the effects on inflammatory response and oxidant status during CPB when compared to roller pump. Nevertheless, we believe that our results should be supported by further clinical and experimental studies.

Iloprost and vitamin C attenuates acute myocardial injury induced by suprarenal aortic ischemia-reperfusion in rabbits.

OBJECTIVE: The aim of this study was to evaluate antioxidant and cytoprotective effects of iloprost and Vitamin C in a distant organ after abdominal aorta ischemia-reperfusion injury. MATERIAL AND METHODS: Twenty-eight New Zealand rabbits weighing 2,400-2,800 g were used for this study. The rabbits were divided into four equal groups. These groups are control group, sham group, iloprost group, and iloprost+vitamin C group. Suprarenal aorta was occluded with a vascular clamp. Following 30 minutes of ischemia, the vascular clamp was removed. Rabbits in group 3 received 10 ng/kg/min iloprost and those in group 4 received 10 ng/kg/min iloprost and 10 mg/kg vitamin C. At the end of the reperfusion period, the rabbits were sacrificed by a high intraperitoneal dose of xylazine+ketamine injection. Myocardial tissue samples were taken for electron microscopic analysis. We evaluated SOD, MDA and catalase in myocardial tissue samples. RESULTS: Iloprost and iloprost+vitamin C groups significantly reduced the oxidative stress markers in tissue samples (p<0.05) and significantly decreased the myofibrillar injury and mitochondrial morphology changes in the myocardial tissue as shown with electron microscopy (p<0.05). Myocardial edema was significantly alleviated by iloprost and iloprost+vitamin C administration (p<0.05). CONCLUSIONS: This study clearly showed that myocardial injury and edema occurred after ischemia-reperfusion of abdominal aorta and that groups administered with iloprost and iloprost+vitamin C showed an attenuation of ischemia-reperfusion injury in distant organs (Tab. 3, Fig. 4, Ref. 30).

Effects of calcium dobesilate and diosmin-hesperidin on apoptosis of venous wall in primary varicose veins.

BACKGROUND: Evaluation of the therapeutic effects of calcium dobesilate and diosmin-hesperidin through regulation of apoptosis. PATIENTS AND METHODS: 56 Patients were divided into four groups; Group 1 consisted of patients (n = 18) with the recent diagnosis of primary varicose disorder who have never used medications, Group 2 consisted of patients (n = 14) who have used diosmin-hesperidin for at least six weeks prior to the operation, Group 3 consisted of patients (n = 14) who have used calcium dobesilate for at least six weeks prior to the operation and finally Group 4 (Control group) consisted of normal saphenous vein biopsies (n = 10). All biopsies were stained with Hematoxylin and Eosin. Tissue samples from 56 patients were immunohistochemically stained with antibodies of anti-bcl-2, anti-bax and anti-p53. Apoptosis was evaluated by TUNEL method. RESULTS: There were no statistically significant differences among the groups in respect to gender distribution and smoking status. Immunohistochemical evaluation of apoptosis related proteins revealed a statistically significant difference between Group 4 and the other groups with respect to the apoptag staining on venous wall (p = 0.026). There were significant differences in the presence of bcl-2 protein expression between groups 4 and Group 1 (p = 0.0002) and between Group 1 and Group 3 (p = 0.023). CONCLUSIONS: Our study highlights the significance of apoptosis in varicose disorders and suggests that calcium dobesilate, which is used in the treatment of varicose veins, could be of benefit by regulating apoptosis.

Long-term effects of combined iliac dilatation and distal arterial surgery.

PURPOSE: When standard aortofemoral surgical procedure is combined with lower extremity vascular surgery, problems related with the hospital stay, morbidity, mortality and the cost of treatment will exist. The number of reports relating to combined iliac artery PTA and distal bypass surgery is limited. After the development of stenting procedures, the results of arterial system plasty have much more improved. This report reviews our preliminary experience with iliac artery angioplasty with distal bypass procedures. PATIENTS AND METHODS: A total of 41 patients have undergone combined iliac artery dilatation and distal arterial revascularization. Angioplastic procedures were performed in the angiography suite and distal surgery was carried out at the same day or the day after. Of all patients, 29 underwent percutaneous transluminal angioplasty (PTA) and 12 underwent combined PTA and stent placement. Ipsilateral femoropopliteal bypass was performed as a distal revascularization procedure in all patients. RESULTS: Mean systolic iliac artery pressure gradients improved from 34.7+/-8.6 mmHg to 3.9+/-3.2 mmHg after angioplastic procedures (P < 0.0001). Six patients needed reangioplasty because of restenosis in the follow-up period. Thrombectomy was performed on 1 patient in the early postoperative period and re-do femoropopliteal bypass was performed on two patients in the 2nd and 23rd months. Three minor wound infections were successfully treated with antibiotics and local care. Mean follow-up was 21.4 months (range 1-48 months). By life-table analyses, the overall 4-year cumulative primary patency of combined procedures was 78.1%. CONCLUSION: The results show that the combined procedure is a suitable method for the treatment of patients with multiple stenotic lesions at the iliac and distal arterial levels. We believe that the combined use of PTA and distal vascular surgery by an experienced surgical team will give beneficial results and a highly satisfactory outcome in this group of patients.

Coronary artery bypass grafting (CABG) after successful percutaneous transluminal coronary angioplasty (PTCA): is PTCA a risk for CABG?

We studied patients who underwent a coronary artery bypass grafting (CABG) procedure with previous percutaneous transluminal coronary angioplasty (PTCA). Forty patients had undergone successful PTCA, and required subsequent CABG, between January 1993 and June 1996 (Group I). These patients were matched with 40 patients surgically revascularized without previous PTCA at the same term (Group II). There were no statistical differences among sex, diabetes mellitus, hypertension, family history, smoking, hypercholesterolemia and prior myocardial infarction within the groups. The mean ages were 50.7+/-9.4 and 54.7+/-7.7 years, respectively, in Group I and Group II (P = 0.02). Preoperative mean ejection fraction values were 59+/-5% in Group I and 56+/-7% in Group II (P = 0.01). The mean follow-up period was 21.0+/-9.8 months (1-38 months) for both groups. CABG operations were performed 11.4+/-6.0 months after PTCA. Number of grafts were 2.1+/-0.7 and 2.3+/-0.8 per patient in Group I and Group II, respectively. Mean aortic cross-clamping times were 18+/-3 and 17+/-4 min/graft (P = 0.01) and cardiopulmonary bypass (CPB) times were 34+/-7 and 29+/-7 min for Group I and Group II, respectively, (P = 0.0001). The duration of hospital stay were 9.1+/-2.5 days for Group I and 8.0+/-1.1 days for Group II (P = 0.008). Freedom from angina at the end of 3 years was 82.5% and 87.5% for Group I and Group II, respectively. One early and two late deaths occured in Group I. One early death and one late death occured in the other group. Survival rates for three years were 92.5% and 95% in Group I and in Group II, respectively. In conclusion, the method of initial revascularization procedure should be considered carefully, as markers of more severe disease may indicate primary CABG and avoidance of an initial PTCA. The initial PTCA may complicate the operation and may increase postoperative morbidity and mortality.

The dose-dependent effects of L-carnitine in myocardial protection in normothermic ischemia.

L-Carnitine has been shown to improve the post-ischemic recovery of myocardial function and metabolic measurements that are reduced in the course of ischemia and reperfusion of the heart. In this study we used 40 male guinea-pigs in order to determine if the effect of L-carnitine which is used in the protection of the post-ischemic reperfused heart, is dose-dependent or not. All harvested hearts were perfused for 30 min on modified Langendorf apparatus with oxygenized Krebs-Henseleit solution. After this period, in (n = 10), 5 mmol and 10 mmol (group B, n = 10) of L-carnitine were added into a Krebs-Henseleit solution. After 20 min, perfusion was complete and the hearts were then exposed to normothermic ischemia for 20 minutes. Following the ischemia, hearts were reperfused with the same solutions for 30 min. In group C (n = 10), 10 mmol of L-carnitine was added into the solution at the post-ischemic reperfusion step. In the control group, the same procedures were performed without using L-carnitine. Matching was done according to the contractile force of the heart rate and the levels of malondialdehyde and adenosine deaminase. When 10 mmol L-carnitine was added into the perfusion solutions at the pre-ischemic period, the best results were obtained and myocardial damage was much less than the control group. The protective effects of L-carnitine in normothermic ischemia is dose-dependent and it must be given at the pre-ischemic period.

Mitral and aortic valve replacement using fresh unstented pulmonary and aortic homografts.

The use of prosthetic valves carries a high incidence of complications including thromboembolism, hemolysis, infection, impaired hemodynamic function and mechanical failure. Unstented homograft valves provide a good quality of life, particularly in terms of a reasonable freedom from these complications. This paper presents the first simultaneous replacement of the mitral and aortic valves using fresh unstented pulmonary and aortic homografts collected from the same donor. We believe that this technique will be especially useful in developing countries facing financial difficulties and problems with patient education.