Ismail Malkoc

The Effects of Testosterone on Intestinal Ischemia/Reperfusion in Rats

ABSTRACT Ischemic injury to the gut is believed to occur in many serious clinical conditions. Our aim was to investigate the postischemia/reperfusion (I/R) effects of exogenously administered testosterone on the intestines of normal and orchiectomized rats.Forty-eight rats were divided into eight groups of six animals: (1) Sham-operated control group; (2) Sham-operated + testosterone-treated group; (3) I/R group: Rats were subjected to the surgical procedures and underwent intestinal ischemia for 60 min followed by reperfusion for 60 min; (4) I/R + testosterone-treated group: Rats were subjected to the surgical procedures and received testosterone 100 mg/kg (i.p.); (5) I/R + orchiectomy group: Rats were subjected to the surgical procedures as well as orchiectomy; (6) orchiectomy group: Rats were subjected to the surgical procedures as well as orchiectomy; (7) orchiectomy + testosterone-treated group: Rats were subjected to the surgical procedures as well as orchiectomy and received testosterone 100 mg/kg (i.p.); and (8) I/R + orchiectomy + testosterone-treated group. The histological findings of this study paralleled the observed degree of lipid peroxidation (LPO) and protein oxidation. Intestinal mucosal injury was extensive in the I/R, I/R + orchiectomy, and I/R + orchiectomy + testosterone groups, but was less in the I/R + testosterone group. Histopathological injury also paralleled the degree of oxidative stress. Apoptotic enterocytes were more numerous in the I/R, I/R + orchiectomy, and I/R + orchiectomy + testosterone groups. Administration of testosterone in the presence of testes significantly protected intestinal tissue against I/R mucosal injuries, while administration of testosterone in the absence of testes did not significantly protect intestinal tissue against I/R mucosal injuries.

The protective effects of beta-carotene against ischemia/reperfusion injury in rat ovarian tissue

INTRODUCTION Beta-carotene is a well-known antioxidant and precursor of Vitamin A that has a preventative role in the oxidative damage process. Our aim was to investigate the possible preventive effects of beta-carotene on oxidative damage via experimental ischemia and ischemia-reperfusion models in rat ovaries. MATERIALS AND METHODS A traumatic vascular clamps were used for 3h to induce ischemia (Group 2, 3, 4, 5, 6, 7). The clamps were then removed to allow reperfusion for 3h (Group 3, 6, 7). Sham-operated rats (Group 1) underwent laparotomy without the induction of ischemia/reperfusion injury. Real-Time-PCR was performed to determine IL-1-beta, IL-6 and iNOS expression levels. Histopathological (H&E) and immunohistochemical staining (NF-kβ p65) processes were then performed. Finally, SOD, GSH, and MDA levels were determined. RESULTS Intense hemorrhagic areas were observed in both the ischemia and ischemia/reperfusion groups, whereas minimal hemorrhage was observed in the treatment groups. The ischemia and ischemia/reperfusion groups exhibited extreme immunoreactivity, detected by NF-kβ p65 staining; this reactivity decreased after the application of beta-carotene. The expression of IL-1-beta, IL-6, and iNOS in the injury groups increased significantly, whereas a dose-dependent improvement was observed in the treatment groups. Finally, MDA levels increased significantly and SOD and GSH levels decreased drastically in the injury groups. However, these values obtained from I/R groups were normalized after beta-carotene treatment. DISCUSSION In this study, we demonstrated via molecular and biochemical parameters the protective effect of beta-carotene, which is a potent antioxidant, on the experimental ischemia-reperfusion model.

Should orthopedic surgeons consider the effects of gabapentin administration on bone healing while treating a long bone fracture: experimental study in a rat model

Objective: The main purpose of the present study was to assess the radiographic, histological, and mechanical effects of gabapentin on fracture healing in a rat model of femur fracture. Materials and methods: A standard transverse fracture of the mid-diaphysis was created. A total of 60 female Wistar-Albino rats with the mean age of 13.5 ± 1.2 weeks were used for this experimental trial. The rats were randomized into four groups with 15 animals included in each group. Group A and B were the control groups whereas C and D were the treatment groups. Drugs were delivered by oral gavage twice a day with the daily dosage calculated according to body surface area conversion to the human equivalent dosing regimen of 1200 mg/day. Radiographic, histological, and biomechanical evaluation was performed. Results: We could not detect any statistically significant difference between the control and gabapentin treatment groups according to the comparative assessment of radiographic scores on the 15th and 30th days. Although no significant differences were found between the groups on the 15th day, histological scores were better in the control group on the 30th day. According to the results of biomechanical testing, the fractured femurs resected from the control group exhibited significantly more strength on the 30th day. Conclusions: According to the data we acquired during the present study, administration of gabapentin negatively affects the fracture healing process especially in the aspects of histological progression as well as the biomechanical strength of the callus in a rat model.

Effect of Kineret® on ovarian ischemia reperfusion injury in a rat model.

To investigate the effect of Kineret® on ischemia reperfusion (IR) injury in rat ovaries.

The effect of thiamine and its metabolites on peripheral neuropathic pain Induced by cisplatin in rats

Thiamine pyrophosphate (TPP) is the active metabolite of thiamine. This study aimed to investigate the effects of thiamine and TPP on cisplatin-induced peripheral neuropathic pain (PNP). Male albino Wistar type Rattus norvegicus were divided into six groups (n=6) that received 2 mg/kg cisplatin (CIS), 25 mg/kg thiamine (TM), 2 mg/kg cisplatin+25 mg/kg thiamine (CTM), 25 mg/kg TPP (TPP), 2 mg/kg cisplatin+25 mg/kg TPP (CTPP), or distilled water (healthy group; HG) for 8 days intraperitoneally. Analgesic effect was measured with a Basile Algesimeter. IL-1β, malondialdehyde (MDA), total glutathione (tGSH), thiamine, and TPP were determined in blood samples. Histopathological examinations were performed on removed sciatic nerves. The percent analgesic effects of the CTM and CTPP groups were calculated to be 21.3% and 82.9%, respectively. Increased production of IL-1β and MDA by cisplatin was inhibited by TPP, while it was not inhibited by thiamine. Conversion of thiamine to TPP significantly decreased in the CIS group. Histopathological and biochemical investigations demonstrated that hyperalgesia and sciatic nerve damage developed in the CIS and CTM groups with low TPP levels. These results indicate that cisplatin inhibits the formation of TPP from thiamine, leading to severe PNP. This finding suggests that TPP may be more beneficial than thiamine for the treatment of cisplatin-induced PNP.

Effect of Hippophae rhamnoides Extract on Oxidative Oropharyngeal Mucosal Damage Induced in Rats Using Methotrexate

Objectives The objective of this study is to investigate and evaluate the effect of Hippophae rhamnoides extract (HRE) on oropharyngeal mucositis induced in rats with methotrexate (MTX) through biochemical, gene expression, and histopathological examinations. Methods Experimental animals were divided into a healthy group (HG), a HRE+MTX (HREM) group, HRE group (HREG), and a control group that received MTX (MTXG). The HREM and HREG groups of rats was administered 50 mg/kg HRE, while the MTXG and HG groups were given an equal volume distilled water with gavage. Then, the HREM and MTXG rat groups were given oral MTX at a dose of 5 mg/kg 1 hour after HRE and distilled water was administered. This procedure was repeated for 1 month. At the end of this period, all of the animals were sacrificed with a high dose of anesthesia. Then, the amounts of malondialdehyde (MDA) and total glutathione (tGSH) were determined in the removed oropharyngeal tissues. Interleukin-1β (IL-1β) and tumor necrosis factor-α (TNF-α) gene expressions were measured, and all the tissues were studied histopathologically. Results The amount of MDA was significantly increased in the MTXG group compared to the HREM, HREG, and HG groups (P<0.001). MTX significantly decreased the amount of tGSH in the MTXG group compared to the HREM, HREG, and HG groups (P<0.001). In this study, there were no visible ulcers in the animal group in which the levels of MDA, IL-1β, and TNF-α were high and the level of tGSH was low. However, histopathologic examination revealed mucin pools in wide areas due to ruptured oropharynx glands, and proliferated, dilated, and congested blood vessels and dilated ductal structures in some areas. Conclusion HRE protected oropharyngeal oxidative damage induced by MTX. As an inexpensive and natural product, HRE has important advantages in the prevention of oropharyngeal damage induced by MTX.

Are New Generations Getting Bigger in Size? Anthropometric Measurements in Erzurum

OBJECTIVE When the dimensional measurements of the students who spend most of their time at school are taken into consideration, inappropriate dimensions of school equipment may affect their body and psychological improvements negatively. Anthropometric measurements are necessary for designing the educational equipment of the children at school. It is emphasized that anthropometric measurements of the people living in different climate and altitude conditions will be different. It is mentioned that anthropometric data available for a certain region will be able to change as a result of changing socio-economical conditions and therefore, anthropometric data update is necessary at certain periods. MATERIALS AND METHODS In 2000 anthropometric data obtained from the children between the age of seven and fifteen, who were in sitting and standing positions, were measured with a repeated measurement in the same schools in 2007. RESULTS Mean values of the heights of elbow at standing position of the female students, 8 years old, increased from 72.38 cm in 2000 to 74.67 cm in 2007 (p<0.001). Most of the other measurements in 2007 were larger than those in 2000, giving the impression that new generation children are getting larger in size. CONCLUSION As reported in the literature, anthropometric data should be updated at certain period of times.