Investigation of the role of KATP channels in the cytotoxic effect of cypermethrin on rat-derived aortic smooth muscle cells.

We investigate role of ATP sensitive potassium (KATP) channel in cytotoxic effect of cypermethrin on rat aortic smooth muscle cells. Cytotoxicity analysis was performed at 0, 0.1, 0.5, 10, 50, and 100 µM concentrations of cypermethrin and the cell index (CI) was calculated. KATP currents were recorded using patch clamp technique for 50 and 100 µM concentrations and channel conductivity was determined by obtaining current-voltage characteristics. No cytotoxic effect was observed in the first 72 hours. At the 96th hour, only at 100 µM concentration, the CI value decreased significantly compared to control group and at 120 and 144th hours, it was observed that the CI value decreased significantly at all concentrations. Currents and conductivities were significantly decreased at 50 and 100 µM concentrations. Results gave clues that cypermethrin causes a cytotoxic effect on vascular smooth muscles and that KATP channels may have a role in the emergence of this effect.

Protective effect of paricalcitol in rat testicular damage induced by subchronic 1800 MHz radiofrequency radiation.

In the present study, the possible protective effects of paricalcitol (P) were investigated in testicular damage because of 1800 MHz radiofrequency radiation (RFR) exposure. Male Sprague Dawley rats 8-10 weeks old (n = 28) were randomly divided into four groups as control (C) (n = 7), RFR (n = 7, 1800 MHz RFR 1 h/day for 30 days), P (n = 7, 0.2 µg/kg paricalcitol, 3 times a week for 30 days), and RFR + P (n = 7, 1800 MHz RFR 1 h/day for 30 days +0.2 µg/kg paricalcitol, 3 times a week for 30 days). Testicular tissue was evaluated with histological and biochemical methods. No statistically significant differences were detected between the groups in seminiferous tubule diameters and germinal epithelial thicknesses. While ultrastructural changes were observed in the seminiferous tubule and Leydig cells in the RFR group, these changes were decreased in the RFR + P group. It was found that the Johnsen Score, Ki67, and p63 immunoreactivity scores (IRS), superoxide dismutase (SOD), and catalase (CAT) activities in the RFR + P group were statistically increased as compared to the RFR group and the malondialdehyde (MDA) levels were decreased statistically and significantly. These results show that paricalcitol administration may have an ameliorative effect on testicular damage occurring because of 1800 MHz RFR exposure.

Cytotoxic effect of silica nanoparticles on human retinal pigment epithelial cells.

In recent years, the use of nanotechnology-based methods has become widespread in the treatment of ocular diseases. Silica nanoparticles (SiO2 NPs) are most common used NPs in medical field due to their physicochemical properties. SiO2 NPs can easily cross biological membranes and interact with basic biological structures, causing structural and functional changes in cells. In this study, it was aimed to investigate the dose dependent effect of SiO2 NPs on retinal pigment epithelium (RPE) in vitro using electrobiophysical, biochemical and histological methods. A commercially purchased human RPE (hARPE-19) cell line was used in this study. Cells were divided into four groups as control, 50 µg/mL SiO2, 100 µg/mL SiO2 and 150 µg/mL SiO2 groups. Cell index, apoptotic activity, cell cycle and oxidative stress markers were measured in all groups. Findings in the present study showed that SiO2 nanoparticles reduced cell proliferation, increased oxidative stress, apoptosis and arrest in the G0/G1 phase of the cell cycle as dose dependent manner in ARPE-19 cells. In conclusion, SiO2 exposure can induce cytotoxic effects in RPE cell line. The results of this study provide clues that exposure to SiO2 nanoparticles may impair visual function and reduce quality of life. However, further studies are needed in this regard.

Effect of imipramine on ether à-go-go potassium channel (Kv1.10) expression in DU145 prostate cancer cells.

In recent studies, it has been reported that ion channels play an important role in cancer formation. Therefore, it is possible that the use of pharmacological agents targeting ion channels will allow the development of new strategies for cancer treatment. In this study, we investigate the effect of imipramine on Eag1 channel expression in DU145 prostate cancer cells. Culture cells were divided into 4 groups as the control, 10, 50 and 75 µM imipramine. Eag1 channel currents and conductivity were determined by whole-cell patch-clamp technique and gene expression by real time-polymerase chain reaction (RT-PCR). Current records were taken before (at 0th minute, as control) and 10 min after imipramine administration to the cells. It was observed that all three doses of imipramine significantly reduced Eag1 currents and conductivity compared with the control. However, the differences between dose groups were not significant. Similarly, Eag1 channel protein expression was found to be significantly reduced for all three doses of imipramine compared with the control group, but there was no significant difference in gene expression between dose groups. Obtained results suggested that imipramine has the potential to be used as a pharmacological agent targeting the Eag1 channel in the treatment of prostate cancer.

The effect of 4.5 G (LTE Advanced-Pro network) mobile phone radiation on the optic nerve.

PURPOSE: Rapid development in mobile phone technologies increase the average mobile phone usage duration. This increase also triggers exposure to radiofrequency radiation (RF), which is a risk factor for the health. In this study, it was aimed to investigate the effect of mobile phone working with LTE-Advanced Pro (4.5 G) mobile network on the optic nerve, which is responsible for the transmission of visual information. MATERIAL AND METHODS: Thirty-two rats divided into two groups as control (no RF, sham exposure) and experimental (RF exposure using a mobile phone with LTE-Advanced Pro network; 2 hours/day, 6 weeks). The visual evoked potential (VEP) was recorded and determined amplitudes and latencies of VEP waves. Optic nerve malondialdehyde level, catalase and superoxide dismutase activities were determined. Furthermore, ultrastructural and morphometric changes of optic nerve were evaluated. RESULTS: In VEP recordings, the mean VEP amplitudes of experimental group were significantly lower than control group. In ultrastructural evaluation, myelinated nerve fibres and glial cells were observed in normal histologic appearance both in sham and experimental group. However, by performing morphometric analysis, in the experimental group, axonal diameter and myelin thickness were shown to be lower and the G-ratio was higher than in the sham group. In the experimental group, malondialdehyde level was significantly higher and superoxide dismutase and catalase activities were significantly lower than sham group. There was a high correlation between VEP wave amplitudes and oxidative stress markers. CONCLUSION: Findings obtained in this study support optic nerve damage. These results point out an important risk that may decrease the quality of life.

Effect of Imipramine on radiosensitivity of Prostate Cancer: An In Vitro Study.

Prostate cancer is the most common cancer and leading cause of cancer death for males. Imipramine (IMI), which is a tricyclic antidepressant, has also been shown to has antineoplastic effect. This study was performed to investigate the radiosensitizing effect of IMI on DU145 prostate cancer cell. Cells were divided into 4 groups. Cell index, apoptotic activity, cell cycle arrest, oxidative stress and EAG1 channel currents were determined in all groups. Our findings showed that combined treatment with IMI and radiotherapy (RAD) did not enhance radiosensitivity of DU145 cells but as unexpected finding, treatment of IMI alone was more effective in DU145 cells.

Toxic effect of acetamiprid on Rana ridibunda sciatic nerve (electrophysiological and histopathological potential).

In this study, the effects of a neonicotinoid insecticide acetamiprid on the sciatic nerve of Rana ridibunda were investigated by using electrophysiological and histological methods. A total of 35 preparations of sciatic nerve isolated from 35 frogs (Nervus ischiadicus) were used in the experiments. Experiments were designed as four different dose groups (n = 8 per group). Acetamiprid solutions of 1 (group 1), 10 (group 2), 100 (group 3), and 1000 µM (group 4) were applied to the nerves in dose groups. In each group, action potentials were recorded before application of acetamiprid which served as control data. The extracellular action potentials were recorded for each group of 30th, 60th, 90th and 120th min of application time. Action potential amplitude and area were measured from recordings. Histological evaluation was performed by transmission electron microscopy. In electrophysiological examination, all doses in which acetamiprid applied have shown the effect from the 30th min and suppressed the sciatic nerve action potential. Acetamiprid significantly reduced the amplitude at the rate of 78-96% and the area at the rate of 79-98% (p < 0.05). In electron microscopic examination, the control nerves were in normal appearance. Disorganization, irregularity, dense ovoid body formation, fragmentation of the myelin sheath, and loss on some axoplasm of the nerves in the dose group have been observed. Our findings showed that acetamiprid can cause neuropathic changes in sciatic nerve at all applied doses. These results indicate that acetamiprid as other insecticides can have harmful effects on non-target organisms.

Analyzing the effect of laparoscopy duration time on peroperative gastroesophageal reflux

Background/aim: Intraabdominal pressure (IAP) is one of the main reasons for gastroesophageal reflux (GER). This study investigates whether IAP during laparoscopic surgery leads to GER in a time-dependent manner. Materials and methods: In a laparoscopy model, 15 mmHg IAP was created in 8 Wistar albino rats in the Trendelenburg position (TP). A 5 mm laparotomy was performed in the left lower abdominal region, and a 6 Fr catheter was placed intraabdominally. Air was insufflated into the abdominal cavity, and the pressure was kept constant at 15 mmHg. Esophageal pH alterations were measured by pH sticks for 4 h every 30 min. Results: The basal median esophageal pH value was 9 (8­10), the value after placing the catheter was 9 (7­10) (P = 0.47), and the median pH value after placing the subjects in TP was 9 (8­10) (P = 0.70). In our experimental model, esophageal pH values were found to decrease significantly at the 150th minute in TP and at 15 mmHg IAP (P < 0.05). Two rats died: one at the 120th minute and the other at the 240th minute (P > 0.05) Conclusion: Esophageal pH values decreased and continued to remain low following IAP increase and TP in this experimental rat model. Prolonged laparoscopic procedures can particularly lead to GER that requires instant recognition and rapid and appropriate intervention.

Effect of low-level 1800 MHz radiofrequency radiation on the rat sciatic nerve and the protective role of paricalcitol.

The nervous system is an important target of radiofrequency (RF) radiation exposure since it is the excitable component that is potentially able to interact with electromagnetic fields. The present study was designed to investigate the effects of 1,800 MHz RF radiation and the protective role of paricalcitol on the rat sciatic nerve. Rats were divided into four groups as control, paricalcitol, RF, and RF + paricalcitol. In RF groups, the rats were exposed to 1,800 MHz RF for 1 h per day for 4 weeks. Control and paricalcitol rats were kept under the same conditions without RF application. In paricalcitol groups, the rats were given 0.2 µg/kg/day paricalcitol, three times per week for 4 weeks. Amplitude and latency of nerve compound action potentials, catalase activities, malondialdehyde (MDA) levels, and ultrastructural changes of sciatic nerve were evaluated. In the RF group, a significant reduction in amplitude, prolongation in latency, an increase in the MDA level, and an increase in catalase activity and degeneration in the myelinated nerve fibers were observed. The electrophysiological and histological findings were consistent with neuropathy, and the neuropathic changes were partially ameliorated with paricalcitol administration. Bioelectromagnetics. 39:631-643, 2018. © 2018 Wiley Periodicals, Inc.

Effects of silica nanoparticles on isolated rat uterine smooth muscle.

In spite of their widespread use, toxicity of silica nanoparticles (SiO2 NPs) to mammalian has not been extensively investigated. In the present study, it is aimed to investigate the effects and the mechanism of action of 20 nm sized SiO2 NPs on isolated uterine smooth muscle. A total number of 84 preparations of uterine strips were used in the experiments. Study was designed as four groups: group I (control), group II (0.2 mM SiO2 NPs), group III (0.4 mM SiO2 NPs) and group IV (0.8 mM SiO2 NPs). Spontaneous contractions were recorded using mechanical activity recording system. Superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) activities and malondialdehyde (MDA) levels were measured using the spectrophotometric methods. Apoptosis of the cells was detected using immunofluorescence staining assay. SiO2 NP distribution and ultrastructural changes were determined by transmission electron microscopy. In groups II-IV, the frequency of contraction was significantly lower than that of the group I, whereas the contraction energy significantly decreased only in group IV. SOD and GSH-Px activities were significantly lower in experimental groups compared to the control group. MDA level and apoptotic cells were significantly higher in all SiO2 groups compared to the control group. Numerous SiO2 NPs in cytoplasm and connective tissue were observed in all dose groups. These findings showed that 20 nm sized SiO2 NPs enter the connective tissue and cytoplasm of uterine muscle cells and cause oxidative stress and apoptosis leading to impaired uterine contractile activity.

Is mycophenolate mofetil an alternative agent to corticosteroids in traumatic nerve paralysis?

OBJECTIVE: The effects of an immunosuppressive agent, mycophenolate mofetil (MM), were investigated and compared with those of methylprednisolone (MP) and dexamethasone (DXM) on the traumatic nerve function. STUDY DESIGN: This is a randomized controlled animal study. MATERIALS AND METHODS: This experimental study was performed on 84 male Wistar albino rats. The rats were assigned to 12 groups each consisting of 7 animals. The groups were formed according to application of normal-dose DXM (group 1A-B), high-dose MP (group 2A-B), normal-dose MP (group 3A-B), MM (group 4A-B), and MM with high-dose MP combination therapies (group VA-B). Right sciatic nerve dissection was performed, and compound muscle action potential thresholds were recorded. The nerve was traumatized with the compression of a Jeweller forceps for 20 seconds. Posttraumatic thresholds were also recorded. The compound muscle action potential thresholds were recorded in the first and fourth weeks for the assigned groups. Then, the nerve was transected and prepared for electron microscopic and histopathologic examinations. Nitric oxide and malondialdehyde assessments were performed on both tissue and blood samples. RESULTS: Only the MM and MP+MM groups had satisfactory electron microscopic findings and were about to reach the tissue characteristics of the control animals. Despite the electrophysiologic recovery, the DXM group was found to have poor electron microscopic scoring. CONCLUSIONS: Mycophenolate mofetil has been found to be beneficial in the treatment of traumatic nerve paralysis. Although a complementary investigation is needed, this immunosuppressive agent may be an alternative to corticosteroids for the selected cases where steroid therapy is contraindicated.

Pressure applied during surgery alters the biomechanical properties of human saphenous vein graft.

Pressure applied during harvesting of the saphenous vein (SV) graft in coronary artery bypass surgery might change its mechanical properties and thereby decrease the patency. This study was performed to assess the mechanical properties of the SV graft distended manually with different levels of pressure and to determine the pressure level that induces changes in its structure and mechanics. Saphenous vein graft segments, collected from 36 patients undergoing coronary artery bypass surgery, were distended with pressures of either 50-60, 75-100, or 130-150 mmHg. Grafts were tested for the stress-strain relationship; the Young's moduli at the low- and high-strain regions were calculated, and their structures were examined by light and electron microscopy. Pressures of 50-60 mmHg did not influence the mechanics of the vein graft, whereas pressures of 75-100 mmHg elevated the elastic modulus of the vein at the low-strain region while pressures above 130 mmHg increased the elastic moduli at both low- and high-strain regions. There was a prominent loss of microfibrils at all distending pressure levels. The mechanical results suggest that distending pressures above 75 mmHg might play a role in graft failure. Furthermore, the absence of microfibrils surrounding elastin suggests that application of distending pressures, even as low as 50 mmHg, can cause degeneration of the elastic fibers following implantation, increasing the stiffness of the graft and thus impairing the graft's function under its new hemodynamic conditions.

The effect of trapidil and bevacizumab on tracheal anastomotic wound healing.

BACKGROUND: Although bevacizumab has deleterious effects on the healing of colonic anastomoses, trapidil improves wound healing of colonic and tracheal anastomoses. OBJECTIVE: We aimed to assess the effects of bevacizumab and trapidil on wound healing after tracheal transection. MATERIALS AND METHODS: We evaluated 35 rats divided in 5 groups: bevacizumab (Group I, n = 7), trapidil (Group II, n = 7), trapidil + bevacizumab (Group III, n = 7), controls (Group IV, n = 7), and sham (Group V, n = 7). Anastomotic healing was assessed by measurement of bursting pressure and inflammation score at the anastomotic region on the seventh day. RESULTS: The bursting pressures of Group II, Group III, and Group V were significantly higher than controls (P = 0.001, P = 0.033, and P = 0.035, respectively). Fibrosis was significantly high in the sham group when compared with the other four groups (P = 0.047). CONCLUSIONS: Although bevacizumab seems to impair anastomotic healing, trapidil can be suggested to improve tracheal anastomoses.

[Effects of abdominal adhesion-preventing 4% icodextrin solution on healing of bowel anastomoses]. / Karin içi adezyon önleyici %4'lük ikodekstrin solüsyonunun gastrointestinal sistem anastomozlari üzerine etkisi.

BACKGROUND: We aimed to introduce the efficiency of 4% icodextrin solution on preventing adhesions and its effect on anastomotic healing, together with biochemical parameters. METHODS: In total, 40 rats were divided into four groups of 10 rats each as Group A (abrasion+icodextrin), Group B (abrasion), Group C (anastomosis+icodextrin), and Group D (anastomosis). Adhesion grade, anastomotic bursting pressure, histopathological analysis, tissue hydroxyproline level, and serum myeloperoxidase (MPO), nitric oxide (NO), and malondialdehyde (MDA) values were examined. RESULTS: Adhesion score was significantly lower in Group A than in Group B and significantly lower in Group C than in Group D (p=0.003577, p=0.001612). No difference in anastomoses healing was determined between Group C and Group D (p=0.816). Hydroxyproline level was significantly higher in Group A than in Group B and significantly higher in Group C than in Group D (p=0.001, p=0.0001). There were no differences in NO and MDA levels between Group A and Group B, but values were significantly lower in Group C than in Group D (p=0.434, p=0.001, p=0.116, p=0.018). MPO level was significantly lower in Group A than in Group B and significantly lower in Group C than in Group D (p=0.0001, p=0.0001). CONCLUSION: Based on our results, 4% icodextrin solution evidently decreased the formation of adhesion without negatively affecting the anastomotic healing. We also reported herein the biochemical and histopathological results and adhesion scores.

Comparison of the effects of different electrocautery applications to peripheral nerves: an experimental study.

BACKGROUND: This study was designed to investigate the effects of bipolar and mononopolar electrocauterization on peripheral nerve tissue. The comparison on the deleterious effects of the different cautery modalities and the importance of probe tip placement are evaluated using electrophysiological, electron microscopic and biochemical assessment parameters. METHODS: Ninety-eight male Wistar albino rats, each weighing 250-275 g, were randomly divided into 14 groups. Each group consisted of seven animals. Monopolar and bipolar electrocautery were performed at 15 watts. The application was performed either directly on the nerve or 1 mm lateral to the longitudinal axis of the nerve for 'near the nerve groups', respectively. RESULTS: The electrophysiological findings showed that the mean amplitudes were at the lowest value in the first day for all the groups. At the end of the 3rd week, we recognised that the electrophysiological recovery continued. Electron microscopic evaluation showed myelin disruption in all groups. Myelin disruption of healthy neurons was at the highest level in the 1st day of application in accordance with the electrophysiological findings. Biochemical evaluation revealed statistical significance between the control and the two of the 'near the nerve groups' (GIII and GV) for NO (nitrite and nitrate) serum level. CONCLUSION: The data of the present study might suggest that electrocautery, independent of the type and form of application, may result in significant damage in histological and electrophysological basis. Although the relative proportions cannot be ascertained, the time course of recovery suggests that both axon and myelin damage have occurred. The probable electrocautery damage may be of substantial importance for the situation that the nerves are displaced by tumor masses or atypical neural traces.

An insight to tympanic membrane perforation pressure through morphometry: A cadaver study.

INTRODUCTION: A cadaveric experimental investigation aimed to show the rupture pressure of the tympanic membrane (TM) for otologists to evaluate its tensile strength. METHODS: Twenty adult ears in 10 fresh frozen whole cadaveric heads (four males, six females) mean age 72.8 (SD 13.8) years (range 40-86) were studied. The tensile strength of the TM was evaluated with bursting pressure of the membrane. The dimensions of the membranes and perforations were measured with digital imaging software. RESULTS: The mean bursting pressure of the TM was 97.71 (SD 36.20) kPa. The mean area, vertical and horizontal diameters of the TM were 57.46 (16.23) mm2, 9.54 (1.27) mm, 7.99 (1.08) mm respectively. The mean area, length and width of the perforations were 0.55 (0.25) mm2, 1.37 (0.50) mm, and 0.52 (0.22) mm, respectively. Comparisons of TM dimension, bursting pressure, and perforation size by laterality and gender showed no significant differences. The bursting pressure did not correlate (positively or negatively) with the TM or perforation sizes. CONCLUSIONS: The TM can rupture during activities such as freediving or scuba diving, potentially leading to serious problems including brain injuries. Studying such events via cadaveric studies and data from case studies is of fundamental importance. The minimum experimental bursting pressures might better be taken into consideration rather than average values as the danger threshold for prevention of TM damage (and complications thereof) by barotrauma.

Enzyme activity and genetic polymorphisms in patients with type II diabetes mellitus.

BACKGROUND: Diabetes mellitus (DM) has become more and more common and has a high morbidity and mortality rate worldwide. It is a multifactorial chronic disease affected by both genetic and environmental factors. OBJECTIVES: To evaluate the association between antioxidant enzyme activities and their genetic variations and the level of malondialdehyde (MDA) in type II diabetes patients living in the Adiyaman province in the southeast part of Turkey. MATERIAL AND METHODS: One hundred patients diagnosed with type II DM (T2DM) and 100 healthy controls were included in the study. Malondialdehyde levels and antioxidant enzyme activities were measured spectrophometrically. DNA isolation was performed and genotyping was carried out using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). RESULTS: Our results revealed no significant differences in genotype distributions and allele frequencies of all polymorphisms between groups (p > 0.05). Significantly elevated MDA levels and a significant reduction in catalase (CAT) and paraoxonase (PON) enzyme activities were observed in patients compared to the control group in terms of study groups and genetic variations (p < 0.05). Moreover, CAT activity was reduced in TT genotype in terms of CAT -262 C/T polymorphism in patients (p < 0.05). Paraoxonase activity was observed to be lower in MM genotype in both groups (p < 0.05). CONCLUSIONS: CAT -262 C/T polymorphism may be one of the factors that lead to severe clinical situation in DM. Our results suggest that TT genotype may be more prone to lipid peroxidation.

Protective effect of N-acetyl cysteine against radiotherapy-induced cardiac damage.

Purpose: Although radiotherapy (RT) is an important component of cancer treatment, it induces adverse tissue reactions in the around of cancer tissue. Therefore, radioprotectives are needed to protect normal tissues. The aim of this study was to investigate the radioprotective effect of N-acetylcysteine (NAC) on RT-induced cardiac damage in rats for the acute term.Materials and methods: The animals were divided into four groups. The rats in control group were injected with saline for 7 d; the rats in NAC group were injected NAC at dose of 240 mg/kg d for 7 d; the rats in RT group were injected with saline for 7 d plus was irradiated 1 h after the last injection and the rats in NAC + RT group were injected with NAC for 7 d and irradiated 1 h after the last NAC dose. The electrocardiogram was recorded and evaluated PR interval, QRS duration, QT interval, T wave alterations and heart rate. Serum interleukin-4, interleukin-6, tumor necrosis factor-alpha, interleukin 1 beta, galectin-3 levels and creatine kinase and creatine kinase isoenzyme-MB activities were determined in all groups. Also, tissue malondialdehyde (MDA) and nitric oxide levels, superoxide dismutase, catalase and glutathione peroxidase activities were determined. In addition, histological changes of heart were evaluated. All measurements were performed 24 h after RT.Results: In the RT group, findings supporting cardiac injury were observed in the electrocardiogram. Also, cytokine levels and oxidative stress were significantly increased. Pretreatment of rats with NAC ameliorated cardiac injury induced by RT.Conclusions: Our findings suggested that NAC may be a potential radioprotector which is capable of preventing cardiac damage.

The effect of Rheum ribes L. on oxidative stress in diabetic rats.

Objectives Rheum ribes L. is a perennial plant that belongs to the family of Polygonaceae, which is often used in traditional therapy because it possesses many bioactivities, such as antioxidant and antibacterial ones. Here we examined the effect of different R. ribes L. extracts on oxidative stress in experimental diabetic rats. Methods Thirty-six rats were divided into six groups as follows: group I, control group; group II, diabetic rats; group III, diabetic rats treated with the aqueous extract of R. ribes L. by gavage at 50 mg/kg for 15 days; group IV, diabetic rats treated by gavage with the ethanolic extract of R. ribes L. at 50 mg/kg for 15 days; group V, nondiabetic rats treated by gavage with the aqueous extract of R. ribes L. at 50 mg/kg for 15 days; group VI, nondiabetic rats treated by gavage with the ethanol extract of R. ribes L. at 50 mg/kg for 15 days. After 15 days, the animals were sacrificed and the liver and kidney tissues of each animal were isolated. Superoxide dismutase (SOD), catalase (CAT), malondialdehyde (MDA) and glutathione peroxidase (GSH-Px) activities in the tissue samples were measured, and histopathologic examination was carried out. Results R. ribes L. was effective in reducing the oxidative stress and increasing the levels of the antioxidant enzymes. Increased levels of MDA and decreased levels of SOD, CAT and GSH-Px were observed in both the liver and kidney tissues in group II. Decreased levels of MDA and increased levels of SOD, CAT and GSH-Px were observed in group III compared with group II. In group IV, decreased levels of MDA and increased levels of SOD, CAT and GSH-Px were observed in comparison with group II. Conclusions Diabetes increases oxidative stress and causes a decrease in antioxidant enzyme levels. Both aqueous and ethanolic extracts of R. ribes L. decrease oxidative stress activity and increase the levels of antioxidant enzymes. The ethanol extract of R. ribes L. has a higher antioxidant effect than the aqueous extract.

Exposure to gamma rays induces early alterations in skin in rodents: Mechanical, biochemical and structural responses.

In this study, the effect of gamma rays has been investigated on the normal rat skin using biomechanical, biochemical and histological techniques. Seventeen male Wistar albino rats were divided into two groups (control (n=7) and irradiated (n=10)). The irradiated group was treated with a (60)Co gamma source at a dose of 10Gy at room temperature. Skin biomechanics were measured with tensile test using biomaterial testing machine and maximum load, stiffness, energy absorption capacity, ultimate stress, ultimate strain and elastic modulus were calculated. In the irradiated group, energy, strain and toughness were significantly lower than in the control group (p<0.05). However, strength, displacement, stiffness, stress and elastic modulus were similar to that of the control group (p>0.05). Catalase (CAT) activities and the levels of malondialdehyde (MDA) in the skin of rats were measured using the biochemical methods. MDA levels significantly increased whereas CAT activities decreased in the irradiated group as compared with the control group (p<0.05). Diameters of collagen fibers were measured by transmission electron microscopy. There was no significant difference (p>0.05) between control and irradiated groups for collagen fiber diameter. Thickness of epidermis was significantly lower than the control group. There were no changes in the epidermis between the irradiated group and the control group ultrastructurally. The results of this study show that the gamma irradiation has a significant effect on normal healthy skin.