Mustafa Serteser

Decreased total antioxidant status and increased oxidative stress in women with polycystic ovary syndrome may contribute to the risk of cardiovascular disease

OBJECTIVE To determine oxidative stress by the level of protein carbonyls and total antioxidant status (TAOS), and whether oxidative stress is associated with increased risk of cardiovascular disease in women with polycystic ovary syndrome (PCOS). DESIGN Controlled clinical study. SETTING University hospital. PATIENT(S) Thirty women with PCOS and 31 healthy control women. INTERVENTION(S) Biometric measures and blood samples collection. MAIN OUTCOME MEASURE(S) C-reactive protein (CRP), lipid fractions, glucose, protein carbonyls, insulin, and other hormone (gonadotropins, androgens) levels and TAOS were measured. The estimate of insulin resistance was calculated by homeostasis model assessment (HOMA-R). RESULT(S) The women with PCOS had significantly higher serum fasting insulin, CRP, protein carbonyl levels, HOMA-R, LH levels, and LH/FSH ratios than healthy women. However, TAOS was significantly lower in women with PCOS. TAOS was negatively correlated with fasting insulin, HOMA-R, CRP, and protein carbonyls. Fasting insulin was positively correlated with protein carbonyls. High density lipoprotein (HDL) was inversely associated with fasting insulin, HOMA-R, and protein carbonyls. CONCLUSION(S) Increased oxidative stress and decreased antioxidant capacity may contribute to the increased risk of cardiovascular disease in women with PCOS, in addition to known risk factors such as insulin resistance, hypertension, central obesity, and dyslipidemia.

The antioxidative and antihistaminic properties of quercetin in ethanol-induced gastric lesions

The role of reactive oxygen species in the pathogenesis of acute ethanol-induced gastric mucosal lesions and the effects of quercetin were evaluated in an experimental model. In addition, the effects of quercetin on gastric damage were evaluated histopathologically. Rats were divided into three groups as control rats, ethanol treated rats and ethanol+quercetin treated rats. Ethanol group was given a gastric gavage containing 1 ml of 80% ethanol (v/v) prepared in distilled water. Quercetin (200 mg/kg body wt.) was given by intragastric gavage 120 min before the administration of ethanol. Gastric tissue thiobarbituric acid reactive substance levels, carbonyl compounds, histamine levels and myeloperoxidase activities were found to be increased in ethanol treated rats and quercetin treatment reversed these increases. No statistically significant changes were found between all groups in catalase activity. The superoxide dismutase activity dropped significantly after ethanol treatment and quercetin treatment increased this enzyme activity. Gastric damage was confirmed histomorphometrically by significant increases in the number of mast cells and gastric erosions in ethanol treated rats. It was also confirmed that quercetin treatment significantly decreased the number of mast cells and reduced the area of gastric erosions. The results suggest that the gastroprotective effect of quercetin in this experimental model could be due to its antiperoxidative, antioxidant and antihistaminic effects.

The effect of different intraabdominal pressures on lipid peroxidation and protein oxidation status during laparoscopic cholecystectomy

Background: This prospective, randomized, and controlled study was designed to investigate the effects of different intraabdominal pressures (IAPs) on lipid peroxidation and protein oxidation status during laparoscopic cholecystectomy (LC). Methods: Twenty-four patients (12 men, 12 women) who underwent LC at either 10 or 15 mmHg of IAP were randomized into two groups. Repeated blood samples were collected to measure thiobarbituric acid reactive substances (TBARS) levels to assess lipid peroxidation and protein carbonyl content and protein sulfhydryl groups to assess protein oxidation status. Results: Serum protein carbonyls and TBARS levels were found to be increased immediately after desufflation in both study groups when compared to the preoperative levels. On the other hand, protein sulfhydryl levels were found to be decreased in both study groups. Although increases in protein carbonyls and TBARS levels were more prominent in patients who underwent LC at 15 mmHg of IAP, this difference was not statistically significant between both groups. Conclusions: The results suggest that both 15 and 10 mmHg of LAP could lead to an increased oxidative stress response during LC, but no difference was found between the groups.

Can preconditioning reduce laparoscopy-induced tissue injury?

Background: Pneumoperitoneum (P) created to facilitate laparoscopy (L) is associated with splanchnic perfusion, ischemia/reperfusion (I/R) injury, and oxidative stress. In this randomized controlled experimental study with blind outcome assessment, we evaluated the effect of preconditioning (PRE) on L-induced I/R injury. Methods: The subjects were 40 Sprague-Dawley male rats. P was created in all except controls, using carbondioxide (CO2) insufflation under a pressure of 15 mmHg. PRE consisted of 10 min of P, followed by 10 min of deflation (D). The rats were randomized to the following groups: Group P was subjected to 60 min of P. Group P/D was subjected to 60 min of P, followed by 45 min of D. Group PRE/P was subjected to PRE, followed by 60 min of P. Group PRE/P/D was subjected to PRE, followed by 60 min of P and 45 min of D. Group C (control) was subjected to a sham operation, without P. Its anesthesia time was equal to that for group PRE/P/D. At the end of the experiments, the rats were killed; blood, liver, and kidney samples were then obtained and coded. Plasma alanine aminotransferase (ALT) and malondialdehyde (MDA), as well as homogenized tissue MDA levels and glutathione (GSH) activities, were measured; tissue samples were assessed for histopathological evidence of injury; all assessments were done by investigators blinded to the study design. The results were decoded and analyzed statistically with the Kruskal-Wallis and Mann Whitney tests. A p < 0.05 was considered significant. Results: Plasma ALT as well as plasma, liver, and kidney MDA levels and liver and kidney injury scores were increased, whereas liver and kidney GSH values were decreased in groups P and P/D, as compared to group C. Rats subjected to PRE before P had plasma ALT, kidney MDA, and kidney and liver GSH levels comparable to controls; their kidney and liver injury scores were higher than controls but significantly lower than nonpreconditioned animals. PRE enabled decreased plasma, kidney, and liver MDA as well as increased kidney GSH if applied before P; its efficacy on oxidative stress was limited to providing decreased kidney MDA and increased kidney GSH if applied before P/D. However, PRE significantly attenuated kidney and liver injury after P as well as P/D. Conclusion: PRE consisting of 10 min of P followed by 10 min of D decreases the oxidative stress induced by sustained P in the plasma, liver, and kidney. PRE significantly limits liver and kidney injury after prolonged P and P/D. After further studies to define its ideal timing, PRE before L incorporating P may have clinical relevance, especially for elderly patients or those with impaired hepatic and/or renal function or perfusion.

Determination of cut-off values for leucocytes and bacteria for urine flow cytometer (UF-100) in urinary tract infections

Leucocytes and bacteria in urine are the important indices for diagnosing urinary tract infections. Urine specimens from 260 patientswere examined for leucocytes and bacteria with the UF-100 flow cytometer (Sysmex Corporation, Japan). The results obtained with the UF-100 were compared with those obtained by bacteriologic cultures of the same urine samples. Bacteriologic samples were found to be positive in 48 urine samples. The best detected cut-off value for bacteria is 3800/μL (senstivity = 73%, specificity = 78%) and 25/μL for leucocytes (sensitivity = 73%, specificity = 92%). In addition, comparison of leucocyte count by manually and with UF-100 shows good correlation (r = 0.91). A flow cytometric urinalysis analyzer operates in a time saving manner, increases throughput and decrease microscopy review rates. It also provides a reliable information to clinicians prior to bacteriologic culture results, in terms of leucocyte and bacteria count.

Oxidant-Antioxidant Status and Pulmonary Function in Welding Workers

Oxidant‐Antioxidant Status and Pulmonary Function in Welding Workers: Fatma Fidan, et al. Department of Pulmonary Diseases, Turkey—Welding is a process during which fumes, gases, electromagnetic radiation and noise are emitted as by‐products. Metal oxide particles are particularly hazardous components of welding fumes. Welding has been found to be associated with respiratory symptoms and our objective in the present study was to study the effects of welding on pulmonary function and serum oxidant‐antioxidant status. Fifty‐one welding workers and 31 control subjects were recruited. Face to face interviews were conducted using the respiratory illness questionnaire adapted from the American Thoracic Society with the addition of demographic characteristics, work history and working conditions. Additionally physical examinations and spirometric measurements were performed at workplaces. Thiobarbituric acid reactive substances (TBARS), protein carbonyls, protein sulfhydryls (SH) and erythrocyte reduced glutathione (GSH) levels were measured to evaluate oxidant‐antioxidant status in 34 welding workers and in 20 control subjects. No statistically significant differences were observed in age, height, weight, body mass index (BMI), smoking status and annual working durations between welding workers and controls. Coughing, sputing and wheezing were significantly higher in welding workers (p<0.05). When adjusted for age, BMI and smoking status in logistic regression, welding work showed a significant risk for chronic bronchitis (OR: 4.78, 95%CI: 1.30– 17.54). Forced expiratory volume in one second (FEV1)/forced vital capacity (FVC) and four parameters of forced expiratory flow (FEF: FEF25, FEF50, FEF75, FEF25–75) levels measured in the welding workers were significantly lower than those in the control group (p<0.05). Serum TBARS and protein carbonyl levels were higher in welding workers than those in controls (p<0.001, p<0.05, respectively). On the other hand, total protein SH groups and GSH levels were significantly lower in welders than those in controls (p<0.05, p<0.001, respectively). Pulmonary function tests and oxidant‐antioxidant status were found to be negatively affected in welding workers chronically exposed to welding fumes and gases. Preventive measures should be taken to improve the health status of these workers.

Changes in serum markers of oxidative stress with varying periods of haemodialysis

Background and Aims:  Oxidative stress possibly helps promote the progression and complications of chronic renal failure (CRF). Haemodialysis (HD) may aggravate oxidative stress. This controlled, cross‐sectional clinical study with blind outcome assessment evaluated the effect of prolonged HD treatment on oxidative stress.

A Comparison of the Oxidative Stress Response and Antioxidant Capacity of Open and Laparoscopic Hernia Repairs

BACKGROUND Free radical-induced lipid peroxidation that is associated with a decrease in the antioxidant status of plasma occurs in many kinds of surgical procedures. In this study, we aimed to investigate markers of oxidative stress--malondialdehyde (as thiobarbituric acid reactive substances), protein carbonyls, and protein sulfhydryls--in patients undergoing Lichtenstein tension-free hernioplasty (LH) or laparoscopic preperitoneal hernia (LPPH) repair. METHODS Seventeen patients with unilateral inguinal hernia and no complications or recurrence were included in this study. Ten were randomized to undergo LH and seven to LPPH repair. Heparinized blood samples were taken to measure the levels of oxidative stress markers in the patients undergoing hernia repair. Levels of malondialdehyde, protein carbonyls, and protein sulfhydryls were measured preoperatively and at 6 and 24 hours postoperatively in all patients. RESULTS Both types of hernia repair caused a significant increase in the oxidative stress response and a decrease in antioxidant activity. Plasma levels of malondialdehyde and carbonyls (indicators of oxidant activity) were significantly higher in the LH than in the LPPH repair group (P<.05), and plasma sulfhydryl levels (indicators of antioxidant activity) were significantly lower in the LH than in the LPPH group (P<.05). In both groups, significant differences were also found between the preoperative levels and the postoperative levels 6 and 24 hours (P<.05). CONCLUSIONS These data demonstrate that both LH and LPPH repair cause a significant increase in markers of oxidative stress; however, the oxidative stress response associated with LH is greater than that associated with LPPH repair.

Gastroprotective effect of leptin on gastric mucosal injury induced by ischemia-reperfusion is related to gastric histamine content in rats.

Leptin has cytoprotective effect to gastric mucosal injury in rats. We aimed to test the hypothesis that leptin induced histamine is involved in the prevention of ischemia-reperfusion (I/R) induced gastric mucosal injury in rats. At the end of the 30 min celiac artery occlusion and 12h reperfusion process, serum and gastric tissue samples were taken from three group of rats to measure oxidative status, histamine levels and for histological examinations. Leptin decreased ulcer and polymorphonuclear leukocyte (PMNL) index, and serum malondialdehyde (MDA) and protein carbonyl content but increased gastric tissue histamine levels. We concluded that leptin exerts a protective effect on gastric mucosa to I/R induced gastric injury probably through increasing tissue histamine content which, in turn, maintain the gastric mucosal blood flow.

Changes in tissue-oxidative stress markers in an experimental model of laparoscopic donor nephrectomy.

Background. Laparoscopic donor nephrectomy (LDN) is associated with prolonged warm ischemia, which could potentially increase oxidative stress in the graft. Because pneumoperitoneum (Pp) used to facilitate LDN impairs renal perfusion, it could augment the effects of warm ischemia. Our experimental, randomized, controlled study with blind outcome assessment is the first to address this possibility. Methods. Wistar-Albino rats were randomized to 4 groups. Controls were subjected to a sham operation; the remainder were subjected to Pp with or without warm ischemia of differing durations. The kidneys were removed at the end of each experiment. The concentrations of malondialdehyde (MDA), protein carbonyl, and sulfhydryl groups and the activities of superoxide dismutase (SOD) and catalase were measured in renal samples as markers of oxidative stress. Renal samples were also evaluated histopathologically using light microscopy. Results. Pp promoted oxidative stress in renal tissues, with an increase of MDA and protein carbonyls and a decrease in protein sulfhydryls and SOD activity. Warm ischemia exerted an additive effect on Pp-associated oxidative stress only when sustained for 10 minutes. These changes occurred in the absence of light-microscopic evidence of overt tissue damage. Conclusion. In an experimental model resembling LDN, Pp and 10 minutes of warm ischemia emerged as additive factors with respect to causing increased oxidative stress in the kidney. Because these effects imply subtle injury not only in the harvested kidneys of live donors but also in the kidneys the donors retain, avoiding Pp and warm ischemia above 5 minutes during LDN appears advisable.