Mehmet Guzeloglu

The Beneficial Effects of Tadalafil on Renal Ischemia-Reperfusion Injury in Rats

Acute renal failure due to ischemia-reperfusion (I/R) injury is a common complication in cardiovascular surgery. We determined the influence of tadalafil on renal injury in a renal I/R model in rats. For this purpose, 21 male Wistar albino rats were separated into 3 groups: sham, placebo and tadalafil. A right nephrectomy was performed, and the left renal pedicles were occluded for 60 min and reperfused for 60 min in the placebo and tadalafil groups. A single dose of tadalafil (10 mg/kg) through an orogastric tube was administered to the tadalafil group. Tubular atrophy with acute inflammation in renal histology, total oxidant status (TOS) and total antioxidant status (TAS) were determined in tissue homogenates. Compared to the tadalafil group, tubular atrophy and acute inflammation was significant in the placebo group. TAS levels were significantly higher in the tadalafil group compared to the placebo (p = 0.01) and sham groups (p = 0.04). While TOS levels were significantly higher in the placebo group (p = 0.03), tadalafil did not significantly alter the TOS levels. The beneficial effects of tadalafil can be attributed to its protective effects on renal tubular cells and inhibition of leukocyte infiltration in renal tissue. We think that tadalafil treatment has an important role in reducing renal injury resulting from renal I/R.

The effects of zoledronic acid on neointimal hyperplasia: a rabbit carotid anastomosis model.

OBJECTIVE The aim of the present study was to investigate the effect of zoledronic acid (ZA), as a matrix metalloproteinase inhibitor, on neointimal hyperplasia in rabbit carotid anastomosis model. METHODS New Zealand male rabbits were divided into two groups as placebo and treatment groups in this experimental study. After anesthesia, the right carotid artery of each rabbit was end-to-end anastomosed with an 8/0 polypropylene suture. Left carotid artery was kept as control without any operation. Placebo group (n=6) received phosphate buffered saline (PBS) (0.5mL/kg/day/s.c.) for 28 days postoperatively, whereas ZA group (n=6) received ZA (100 µg/kg/day/s.c.) for the same period. After sacrification, the anastomosed and control arteries were isolated. Morphometric and immunohistochemical examinations were performed. Statistical analyses of morphometric and immunohistochemical data were performed using two-way ANOVA and Chi-square test respectively. RESULTS In PBS group, vascular injury in the anastomosed artery significantly increased the intimal area (anastomosed: 112.51±61.18 µm(2)*1000 vs. control: 22.62±4.26 µm(2)*1000, p<0.01) and intima/media index (anastomosed: 0.347±0.29 vs. control: 0.075±0.01, p<0.05) compared to control artery. ZA significantly reduced the intimal area (39.29±18.21 µm(2)*1000 , p<0.01) and intima/media index (0.112±0.07, p<0.05) compared to PBS group. Additionally, α-smooth muscle actin immunopositivity was found significantly decreased in anastomosed arteries from ZA group (ZA: 2.33±0.52 vs. PBS: 3.50±0.5, p<0.05). Moreover, intensive gelatinase (MMP-2 and MMP-9) immunoreactivities were clearly seen in anastomosed arteries compared to control arteries from PBS group. ZA apparently decreased immunopositivities for gelatinases in anastomosed arteries. CONCLUSION ZA might be a promising agent for prevention of neointimal hyperplasia, which is the most significant cause of graft failures in late postoperative period.

Bedside Surgery to Treat Patent Ductus Arteriosus in Low-Birth-Weight Premature Infants

Background Patent ductus arteriosus (PDA) is commonly seen in premature infants with low birth weights (LBW). It is a condition that has high mortality and morbidity rates. Early closure of the ductus arteriosus may require surgery or medical treatment. However, the decision of first medical approach for symptomatic PDA closure is still debated. In this study, we compared the surgical and medical treatments for the closure of PDA in premature LBW infants. Methods This study included 27 premature infants whose birth weights were lower than 1500 g, who were born in the period between 2011 and 2013 and had symptomatic PDA. Patients were separated into two groups: groups A and B. Group A included patients whose PDAs were closed with medical treatment (n = 16), and group B included patients who had undergone surgical operations for PDA closure (n = 11). Results There were no statistically significant differences between groups A and B when the groups were compared in terms of birth weight, gestational age, respiratory distress syndrome (RDS), necrotizing enterocolitis (NEC), sepsis, intraventricular hemorrhage (IVH), retinopathy of prematurity (ROP), and pneumothorax. Although the mortality rate was determined to be lower in group B (2 out of 11, 18.1%) than in group A (7 out of 16, 43.7%), no statistically significant difference was found between the two groups. A statistically significant increase was determined in the incidence of kidney function loss in patient group that received Ibuprofen, a medical treatment, in comparison to the patients who had surgery. Conclusion In conclusion, surgery is a safe method to repair PDA in premature LBW infants. Although there is no remarkable difference between surgery and medical treatment, we suggest that a surgical approach may be used as a first choice to repair PDA considering the lower rate of mortality and morbidity and higher rate of closure compared to medical treatment.