Engin Yenilmez

Effects of Early Versus Delayed Nutrition on Intestinal Mucosal Apoptosis and Atrophy After Traumatic Brain Injury

PurposeTo determine the optimal time to start nutritional support after traumatic brain injury (TBI).MethodsRats were divided into six groups of seven. All but one of these groups were subjected to moderate closed head trauma under general anesthesia. Groups Ia and Ib were commenced on immunonutrition and standard enteral nutrition, respectively, 8 h later; groups IIa and IIb were commenced on immunonutrition and standard enteral nutrition, respectively, 72 h later; and group III was commenced on a parenteral saline infusion 8 h later. Group IV was a control group fed a laboratory diet and not subjected to trauma. The rats were killed 7 days later, and ileal segments were examined using light and electron microscopy. We used the deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick end labeling (TUNEL) technique to detect intestinal mucosal apoptosis.ResultsGroup III had a lower body weight than the other groups (P < 0.005). The mean villous height was highest in groups Ia and IV and lowest in group III. The villi count was lower in groups Ib, IIa, IIb, and III than in group IV (P < 0.005). The apoptotic index counts were higher in groups IIa, IIb, and III than in group IV (P < 0.005).ConclusionsThe addition of enriching immunonutrients to early enteral feeding helps preserve an almost normal gut mucosa.

Apoptotic and morphological features of the umbilical artery endothelium in mild and severe pre-eclampsia

Background. The pathology of the umbilical arterial endothelium in normal pregnancy and in pregnancy complicated with pre‐eclampsia remains unclear. In this study the changes that occur in the umbilical artery endothelial cells were examined and endothelial cell morphology and apoptosis were compared among control, mild, and severe pre‐eclamptic subjects. Methods. Umbilical cords with a gestational age of between 35 and 40 weeks were collected from women with normal pregnancies (n=17), mild pre‐eclampsia (n=10), and severe pre‐eclampsia (n=12). We studied the umbilical artery endothelial cells using flow cytometry, and light and electron microscopy. Apoptosis was measured using flow cytometry and the terminal deoxynucleotidyl transferase deoxyuridine triphosphate nick end labeling technique. The Kruskall–Wallis variance analysis and Mann–Whitney U‐tests as post hoc were applied. Results. In mild pre‐eclamptics, the endothelial cells appeared ultrastructurally separated. A dilated endoplasmic reticulum, swollen mitochondria, and vanished mitochondrial cristae were observed. In severe pre‐eclamptics, the cells were disorganized, highly contracted and vacuolated, separated from each other, and protruding prominently into the lumen. The percentages of endothelial cells that underwent apoptosis in mild (p<0.017) and severe pre‐eclamptics (p<0.017) were higher than those in the controls. These apoptosis values were highest in severe pre‐eclamptics (p<0.0001). Conclusion. Apoptosis and structural disruptions in the arterial endothelium of severe pre‐eclamptics were prominent in all subjects. Increased endothelial apoptosis and structural disruptions are clinically related to intensity of pre‐eclampsia, and may be associated with adaptation of the endothelial cells to pre‐eclampsia.

The effects of dabigatran etexilate on fracture healing in rats: An experimental study.

Background: Deep vein thrombosis leading to pulmonary embolism is one of the major complication after fracture. After a fracture occurs, the coagulation cascade activates thrombin, a protease that finally generates clotting. Dabigatran etexilate reduce clot formation by inhibiting thrombin. Dabigatran etexilate is a widely used drug for thromboprophylaxis. There is no study of the effects of dabigatran etexilate on fracture healing in the literature, so we aimed to evaluate the effects of dabigatran etexilate on fracture healing. Materials and Methods: Thirty-six female Sprague Dawley rats were divided into 6 groups, each consisting of 6 rats. In all rats, right tibias were used for the fracture model. An oral regimen of dabigatran etexilate suspension in 0.5% hydroxyethylcellulose was administered to the rats. Although the first and second groups received 10 mg/kg daily doses, the third and fourth groups received 50 mg/kg daily doses. The fifth and sixth groups were assigned as sham groups and only hydroxyethylcellulose solution was administered. The first, third and fifth groups were sacrificed on 14th days; whereas the second, fourth and sixth groups were sacrificed on 28th days. Results were evaluated radiologically and histologically. Results: Radiologically and histologically no statistically significant differences were observed on the 14th day between the first, third and fifth groups; and on the 28th days between the second, fourth and sixth groups. Conclusion: Radiological and histological evaluations revealed that fracture healing was not affected by dabigatran etexilate. We think that dabigatran etexilate can be used for the prophylaxis of thromboembolism in patients with fractures, but further clinical studies are mandatory.