Showing papers by "Zonguldak Karaelmas University published in 2004"

Increased oxidative stress and altered activities of erythrocyte free radical scavenging enzymes in autism.

Abstract: There is great evidence in recent years that oxygen free radicals play an important role in the pathophysiology of many neuropsychiatric disorders. The present study was performed to assess the changes in red blood cells thiobarbituric acid-reactive substances (TBARS) levels, and superoxide dismutase (SOD), catalase (CAT), adenosine deaminase (ADA) and xanthine oxidase (XO) activities in patients with autism (n = 27) compared to age- and sex-matched normal controls (n = 26). In the autistic group, increased TBARS levels (p < 0.001) and XO (p < 0.001) and SOD (p < 0.001) activity, decreased CAT (p < 0.001) activity and unchanged ADA activity were detected. It is proposed that antioxidant status may be changed in autism and this new situation may induce lipid peroxidation. These findings indicated a possible role of increased oxidative stress and altered enzymatic antioxidants, both of which may be relevant to the pathophysiology of autism.

Effects of Nigella sativa on oxidative stress and β-cell damage in streptozotocin-induced diabetic rats

Abstract: The aim of the present study was to evaluate the possible protective effects of Nigella sativa L. (NS) against beta-cell damage from streptozotocin (STZ)-induced diabetes in rats. STZ was injected intraperitoneally at a single dose of 50 mg/kg to induce diabetes. NS (0.2 ml/kg/day, i.p.) was injected for 3 days prior to STZ administration, and these injections were continued throughout the 4-week study. Oxidative stress is believed to play a role in the pathogenesis of diabetes mellitus (DM). To assess changes in the cellular antioxidant defense system, we measured the activities of antioxidant enzymes (such as glutathione peroxidase (GSHPx), superoxide dismutase (SOD), and catalase (CAT)) in pancreatic homogenates. We also measured serum nitric oxide (NO) and erythrocyte and pancreatic tissue malondialdehyde (MDA) levels, a marker of lipid peroxidation, to determine whether there is an imbalance between oxidant and antioxidant status. Pancreatic beta-cells were examined by immunohistochemical methods. STZ induced a significant increase in lipid peroxidation and serum NO concentrations, and decreased antioxidant enzyme activity. NS treatment has been shown to provide a protective effect by decreasing lipid peroxidation and serum NO, and increasing antioxidant enzyme activity. Islet cell degeneration and weak insulin immunohistochemical staining was observed in rats with STZ-induced diabetes. Increased intensity of staining for insulin, and preservation of beta-cell numbers were apparent in the NS-treated diabetic rats. These findings suggest that NS treatment exerts a therapeutic protective effect in diabetes by decreasing oxidative stress and preserving pancreatic beta-cell integrity. Consequently, NS may be clinically useful for protecting beta-cells against oxidative stress.

Intramedullary spinal cord metastases: diagnosis and treatment - an illustrated review.

Abstract: Background. Intramedullary spinal cord metastases (ISCM) are rare but, with increasing use of magnetic resonance imaging (MRI) are being encountered with increasing frequency. Optimum treatment remains controversial. On the basis of a review of previous reports and experience with a patient with an ISCM from a large cell lung cancer, we propose practical diagnostic and therapeutic approaches.

Exercise Training Prevents and Protects Streptozotocin- Induced Oxidative Stress and β -Cell Damage in Rat Pancreas

Abstract: The aim of the present study was the evaluation of possible protective effects of exercise against β-cell damage in streptozotocin (STZ)-induced diabetes in rats. The animals were divided into five groups: the control group, the STZ-induced diabetes group, the STZ-induced diabetes and light-intensity exercise group, the STZ-induced diabetes and moderate-intensity exercise group, and the STZ-induced diabetes and heavy-intensity exercise group. Animals in the exercise groups were made to swim one of three exercise protocols once a day for 12 consecutive weeks. STZ was injected intraperitoneally at a single dose of 50 mg/kg for diabetes induction. Exercise training was continued for 4 weeks prior to STZ administration; these applications were continued end of the study (for 12 weeks). Erythrocyte and pancreatic tissue malondialdehyde (MDA) levels and serum nitric oxide (NO) concentration were measured. Moreover glutathione peroxidase (GSHPx), superoxide dismutase (SOD) and catalase (CAT) were also measured in pancreatic homogenates. Pancreatic β-cells were examined by immunohistochemical methods. STZ increased lipid peroxidation and decreased the antioxidant enzyme activity significantly. Exercise, especially moderate-intensity exercise has shown protective effect probably through decreasing lipid peroxidation and increasing antioxidant enzyme activity. Islet cell degeneration and weak insulin immunohistochemical staining were observed in STZ induced diabetic rats. Increased intensity of staining for insulin and preservation of β-cell numbers were apparent in the exercise-applied diabetic rats. Interestingly, the best result was obtained from moderate-intensity exercise. These findings suggest that exercise has a therapeutic and/or protective effect in diabetes by decreasing oxidative stress and preservation of pancreatic β-cell integrity.

The postoperative analgesic effect of tramadol when used as subcutaneous local anesthetic.

Abstract: Recently, it has been shown that tramadol was an effective local anesthetic in minor surgery. In this study, its efficacy for relieving postoperative pain was evaluated. Forty patients undergoing minor surgery (lipoma excision and scar revision) under local anesthesia were included. The patients were randomly allocated into two groups: In group T (n = 20), 2 mg/kg tramadol, and in group L (n = 20), 1 mg/kg lidocaine were given subcutaneously. In both groups, the injection volume was 5 mL containing 1/200,000 adrenalin. The degree of the erythema, burning sensation, and pain at the injection site were recorded. Incision response, which is a degree of the pain sensation during incision, was recorded and graded with the visual analog scale (VAS) 0-10. After incision, VAS values were recorded at 15-min intervals. When the VAS score of the pain during surgery exceeded 4, an additional 0.5 mg/kg of the study drug was injected and this dosage was added to the total amount. Patients were discharged on the same day. Subjects with VAS > or =4 were advised to take paracetamol as needed. No side effects were recorded in either group except for 1 patient complaining of nausea in group T at the 30th min of operation. After 24 h, patients were called and the time of first analgesic use and total analgesic dose taken during the postoperative period were recorded. During the 24 postoperative hours, 18 of 20 (90%) subjects did not need any type of analgesia in group T, whereas this number was 10 (50%) in group L (P < 0.05). The time span before taking first analgesic medication was longer (4.9 +/- 0.3 h) in group T than that of group L (4.4 +/- 0.7 h) (P < 0.05). We propose that tramadol can be used as an alternative drug to lidocaine for minor surgeries because of its ability to decrease the demand for postoperative analgesia.

Oxidant-antioxidant enzymes and lipid peroxidation in generalized vitiligo

Abstract: Vitiligo is a common pigmentary disorder of the skin with selective destruction of melanocytes. The pathogenetic mechanisms in vitiligo have not been completely clarified. The aim of our investigation was to evaluate the oxidative stress in the pathogenesis of generalized vitiligo. Twenty-seven patients with generalized vitiligo and 24 phototype-, age-, and sex-matched healthy controls were included in this study. We analysed serum levels of malondialdehyde (MDA), nitric oxide (NO), and serum activities of superoxide dismutase (SOD) and xanthine oxidase (XO) in the patients with vitiligo and in the controls. We found significantly higher levels of MDA and XO activity (P 0.05). These results suggest that lipid peroxidation of cellular membrane of melanocytes by free radicals may have a significant role in the pathogenesis of generalized vitiligo.

Alterations in plasma essential trace elements selenium, manganese, zinc, copper, and iron concentrations and the possible role of these elements on oxidative status in patients with childhood asthma.

Abstract: The aim of the present study is to evaluate the status of plasma essential trace element selenium (Se), manganese (Mn), copper (Cu), zinc (Zn), and iron (Fe) concentrations and the effect of these elements on oxidative status in patients with childhood asthma. Plasma Se, Mn, Cu, and Zn concentrations were determined by atomic absorption spectrophotometry (AAS) and Fe concentrations, malondialdehyde (MDA), and total antioxidant capacity (TAC) were determined by the colorimetric method. The plasma MDA/TAC ratio was calculated as an index of oxidative status. Plasma albumin levels were measured to determine nutritional status. Plasma Fe concentrations, MDA levels and the MDA/TAC ratio were significantly higher (p 0.05). There were positive relationships between plasma MDA and Fe (r=0.545, p<0.001) and TAC and Se (r= 0.485, p<0.021), and a negative correlation between TAC and MDA values (r= -0.337, p<0.031) in patients with childhood asthma. However, there was no correlation between these trace elements and albumin content in patient groups. These observations suggest that increased Fe and decreased Se concentrations in patients with childhood asthma may be responsible for the oxidant/antioxidant imbalance.

Modified Limberg flap reconstruction compares favourably with primary repair for pilonidal sinus surgery.

Abstract: Background: The present study analyses the results of wide excision with primary closure (PC), wide excision with classical Limberg flap reconstruction (LF) and wide excision with modified Limberg flap reconstruction (MLF) in the surgical treatment of sacrococcygeal pilonidal disease. Methods: One hundred and sixty-two well-documented patients who were operated on for pilonidal disease and followed for more than 1 year were analysed retrospectively. Group 1 was composed of patients with excision plus PC (n = 78) while group 2 included those with excision plus a LF reconstruction (n = 40), and group 3 included those with excision plus a MLF reconstruction (n = 44). Results: There were no significant differences among the three groups with respect to age, sex distribution, frequency of recurrent disease, or follow-up periods (P > 0.05 for all comparisons). Significant disadvantages regarding postoperative infection rate, mobilization time, discharge from hospital, and time off work were noted for primary closure, compared with both LF and MLF reconstructions. Following a median follow-up period of 4.2 years, 14 recurrences (17.9%) developed in the PC group, three (7.5%) in the LF group, and none (0%) in the MLF group. The zero recurrence rate in the MLF group was significantly lower than that in the PC group (P = 0.003). On the other hand, the recurrence rate in the LF was not found to differ significantly from that in the PC group (P = 0.126). Comparing the LF and MLF groups, none of the surgical end points reached a statistically significant difference (P > 0.05 for all comparisons). Conclusions: For the surgical treatment of sacrococcygeal pilonidal disease, excision plus a classical or modified Limberg flap reconstruction proved to be superior to excision plus primary closure in terms of infection, mobilization time, discharge from hospital and time off work. Additionally, MLF reconstruction resulted in a statistically lower recurrence rate when compared with PC.

Craniofacial differences according to AHI scores of children with obstructive sleep apnoea syndrome: cephalometric study in 39 patients

Abstract: Background Cephalometry is useful as a screening test for anatomical abnormalities in patients with obstructive sleep apnoea syndrome (OSAS).

Synthesis and characterization of polymeric linseed oil grafted methyl methacrylate or styrene

Abstract: Syntheses of wholly natural polymeric linseed oil (PLO) containing peroxide groups have been reported. Peroxidation, epoxidation and/or perepoxidation reactions of linseed oil, either under air or under oxygen flow at room temperature, resulted in polymeric peroxides, PLO-air and PLO-ofl, containing 1.3 and 3.5 wt.-% of peroxide, with molecular weights of 2 100 and 3 780 Da, respectively. PLO-air contained cross-linked film up to 46.1 wt.-% after a reaction time of 60 d, associated with a waxy, soluble part (PLO-air-s) that was isolated with chloroform extraction. PLO-ofl was obtained as a waxy, viscous liquid without any cross-linked part at the end of 24 d under visible irradiation and oxygen flow. Polymeric peroxides, PLO-air-s and PLO-ofl initiated the free radical polymerization of both methyl methacrylate (MMA) and styrene (S) to give PMMA-graft-PLO and PS-graft-PLO graft copolymers in high yields with Mw varying from 37 to 470 kDa. The polymers obtained were characterized by FT-IR, (1)H NMR, TGA, DSC and GPC techniques. Cross-linked polymers were also studied by means of swelling measurements. PMMA-graft-PLO graft copolymer film samples were also used in cell-culture studies. Fibroblast cells were well adhered and proliferated on the copolymer film surfaces, which is important in tissue engineering.

A randomized prospective study of complications between general surgery residents and attending surgeons in near-total thyroidectomies.

Abstract: Purpose Recurrent laryngeal nerve palsy and hypoparathyroidism are the most common and serious complications after thyroid operations. Surgeon experience has been defined as a significant factor in the number of complications occurring in thyroid surgery. There has so far been no prospective randomized study that compares the complication rates between residents and the attending surgeon in statistically similar patient groups in which all of the patients undergo the same type of thyroid surgery by the same surgical team. In this prospective study the performances of residents and attending surgeons were evaluated and compared according to the complication rates in near-total thyroidectomies.

Protective effects of quercetin, a flavonoid antioxidant, in absolute ethanol-induced acut gastric ulcer

Abstract: Free radicals have been reported to be responsible for many ailments including gastroduodenal ulcers. Recent studies demonstrated that quercetin (QE) has an antioxidant effects on injuries caused by various toxic agents in different experimental models. In our study, we examined anti-ulcerogen and antioxidant effects of quercetin on ethanol-induced gastric lesions in rats. QE was administered intraperitoneally (i.p.) 50 mg/kg. It was found that pretreatment with QE significantly reduced ethanol-induced gastric damage and malondialdehyde levels, and significantly increased antioxidant enzyme activities. We conclude that QE clearly has antioxidant properties and that the protective effect of QE against ethanol-induced gastric mucosal lesion, at least in part, depends upon the reduction in the lipid peroxidation and an increase in the activity of antioxidant enzymes.

T2-weighted MRI in Parkinson's disease; substantia nigra pars compacta hypointensity correlates with the clinical scores.

Abstract: Background: Iron accumulation in substantia nigra pars compacta (SNpc) and related intensity and volumetric changes in patients with idiopathic Parkinson’s disease (PD) has been reported previously. There are only a few studies evaluating the relation between neuroradiological findings and clinical scores, with contradictory results. Aims: In this study we aimed to measure the iron-rich brain areas of PD patients and healthy subjects with T2-weighted magnetic resonance imaging (MRI) and to evaluate the relation between the clinical scores of PD patients and these imaging results. Methods and Materials: T2-weighted MRI findings were studied in 20 patients with PD and 16 healthy controls. The width of SNpc, putamen volume, and the intensity of the basal ganglia were measured. Unified Parkinson’s Disease Rating Scale (UPDRS) was used for evaluating the clinical status. Statistical Analyses: Mann Whitney U test for group comparisons, Wilcoxon sign rank test for comparisons within the patient group, and Spearman’s rank correlation coefficient for analyses of correlations were used. Results: Mean SNpc and dentate nucleus intensities were lower in PD patients than healthy subjects. Mean SNpc width and putamen volumes were lower in patients. Decrease in the intensity of mean SNpc correlated with high UPDRS and rigidity scores. Conclusion: The results of our study reflect the increase in iron accumulation and oxidative stress in the SNpc in Parkinson’s disease. The decrease in the intensity of SNpc correlates with poor clinical scores.

Epinephrine in digital block: color Doppler flow imaging.

Abstract: Background. Epinephrine is currently added to local anesthetics for its advantageous vasoconstrictive effects. Traditionally, however, its use is not advised for digital block anesthesia due to the risk of digital gangrene. Objective. To observe vasoconstrictive effect of epinephrine in digital block anesthesia. Methods. Digital blocking with epinephrine containing lidocaine was performed in 24 subjects undergoing surgical procedure of their finger and toes. Digital artery blood flows were studied with color Doppler ultrasonography before digital blocking and at 10th, 60th, and if needed 90th minutes after blocking. Doppler parameters such as peak systolic velocity, end diastolic velocity, and resistive index values were studied. Results. There were statistically significant decrease of blood flow rates and an increase of resistive index in all patients within 10 minutes. At the 10th minute of digital block, four patients had no measurable blood flow, which was restored within 60 or 90 minutes. Others showed diminished but persistent blood flow, which returned to normal within 60 minutes. No systemic or local complication related with epinephrine usage was observed. Conclusion. Vasoconstrictive effect of epinephrine in local anesthetics is not persistent and resolves within 60 or 90 minutes. Its use seems to be safe in selected patients.

The protective effect of nebivolol on ischemia/reperfusion injury in rabbit spinal cord.

Abstract: The aim of this experimental study was to investigate whether nebivolol has protective effects against neuronal damage induced by spinal cord ischemia/reperfusion (I/R). Twenty-one rabbits were divided into three groups: group I (control, no I/R), group II (only I/R) and group III (I/R+nebivolol). Spinal cord ischemia was induced by clamping the aorta both below the left renal artery and above the aortic bifurcation. Seventy-two hours postoperatively, the motor function of the lower limbs was evaluated in each animal. The animals were sacrificed at 72 h, and histopathological and biochemical analyses were carried out in the lumbar spinal cords. The motor deficit scores in nebivolol group were different from I/R group at 72 h (3.25±0.70 vs. 1.75±1.28, p=0.01). I/R produced a significant increase in the superoxide dismutase (SOD), xanthine oxidase (XO), adenosine deaminase (ADA) and myeloperoxidase (MPO) activities in spinal cord tissue when compared with control group. Nebivolol treatment prevented the increase of all those enzymes activities produced by I/R. A significant decrease in spinal cord glutathione peroxidase (GSH-Px) level was seen in I/R group and nebivolol treatment prevented the decrement in the spinal cord tissue GSH-Px contents. On the other hand, I/R produced a significant increase in the spinal cord tissue malondialdehyde (MDA) and nitric oxide (NO) contents, this was prevented by nebivolol treatment. In conclusion, this study demonstrates a considerable neuroprotective effect of nebivolol on neurological, biochemical and histopathological status during periods of spinal cord I/R in rabbits.

Effect of chronic fluorosis on lipid peroxidation and histology of kidney tissues in first- and second-generation rats.

Abstract: This experiment was designed to investigate the lipid peroxidation and histological effects of chronic fluorosis on first- and second-generation rat kidney tissues. Sixteen virgin female Wistar rats were mated with eight males (2: 1) for approx 12 h to obtain first-generation rats. Mating was confirmed by the presence of sperm in vaginal smears. Sperm in vaginal smears was observed in 10 of 16 rats (d 0). These rats were identified as pregnant and included in this experiment. Pregnant rats were divided into two experimental groups (control and fluoride-supplemented), each containing five rats. The pregnant rats in the fluoride-supplemented group were exposed to 30 mg/L sodium fluoride (NaF) in commercial drinking water containing 0.07 mg/L NaF throughout the gestation and the lactation periods. After the lactation period, young animals (first generation [F1]) were exposed to the same amount of NaF in drinking water for 4 mo. At the end of the 4-mo experimental period, nine randomly chosen male rats (F1) were sacrificed, and the kidneys were removed for the histological and lipid peroxidation examinations. The remaining eight female rats were mated with four males (2: 1) for approx 12 h to obtain second-generation rats. Six female were identified as pregnant, and treated similarly throughout the gestation and the lactation periods. After the lactation period, the young male rats (second-generation male rats [F2]) were also treated similarly for 4 mo. At the end of the 4-mo experimental period, nine randomly chosen male rats (F2) were sacrificed, and the kidneys were removed for the histological and lipid peroxidation examinations. The rats in the control groups underwent the same procedure without NaF supplementation. It was found that the plasma fluoride and kidney TBARS levels of fluoride-supplemented F1 and F2 rats were higher than controls. Hydropic epithelial cell degenerations and moderate tubular dilatation were observed in some proximal and distal tubules. There were markedly focal mononuclear cell infiltrations and hemorrhage at some areas of the interstitium, especially at the corticomedullar junction. Mononuclear cell infiltrations were also evident in some peritubular and perivascular areas. Most of the vascular structures were congestive. Many Bowman capsules were narrowed. The severe degenerative changes in most of the shrunken glomerules and vascular congestion were also observed.

The effects of peritoneal dialysis and hemodialysis on serum tumor necrosis factor-alpha, interleukin-6, interleukin-10 and C-reactive-protein levels.

Abstract: BACKGROUND: Markers of an acute phase reaction, such as C-reactive protein (CRP) or tumor necrosis factor-alpha (TNF-alpha) and interleukin (IL)-6, are predictive for cardiovascular morbidity and mortality in normal subjects and in chronic renal failure patients. In this study, we aimed to investigate serum TNF-alpha, IL-6, IL-10 and CRP levels in continuous ambulatory peritoneal dialysis (CAPD) and hemodialysis (HD) patients. MATERIALS AND METHODS: Serum levels of TNF-alpha, IL-6, IL-10 and CRP levels were measured in 30 patients who were just diagnosed with end-stage renal failure and treated, with 16 CAPD (nine female, seven male) and 14 HD (eight female, six male) patients, before CAPD or HD treatment and after 3 months from the beginning of CAPD or HD in patients with no clinical signs of infection. The control groups were 20 healthy persons of similar age and sex. Serum levels of TNF-alpha, IL-6, IL-10 and CRP were measured by enzyme-linked immunosorbent assay in stable CAPD and HD patients and in healthy persons. RESULTS: The mean serum levels of TNF-alpha, IL-6, IL-10 and CRP showed no significant differences between the CAPD and HD patients for the beginning values and the third month of treatment. However, serum TNF-alpha, IL-6, IL-10 and CRP levels were higher than the control group in the CAPD and HD patients regarding the beginning values and the third month of treatment (p < 0.001). CONCLUSIONS: CAPD and HD of the renal replacement therapy have no effects on serum CRP and cytokines.

Significance of Asymptomatic Tonsil Asymmetry

Abstract: OBJECTIVE: Asymmetry of tonsils that arouses suspicion for malignancy is one of the indications for tonsillectomy. The purpose of this study was to evaluate the incidence of occult malignancy in pa...

Serum levels of tumor necrosis factor-alpha, interleukin-6 and interleukin-8 are not increased in dyspeptic patients with Helicobacter pylori-associated gastritis

Abstract: Introduction: Helicobacter pylori (H. pylori) is a non-invasive microorganism causing intense gastric mucosal inflammatory and immune reaction. H. pylori-induced gastric mucosal cytokine overproduction has been clearly documented previously. The stomach has a large surface area and continuous spill-over of locally produced cytokines into the blood stream is a possibility. There are few and conflicting data on circulatory proinflammatory cytokine levels in patients with H. pylori infection.

Near-total thyroidectomy could be the best treatment for thyroid disease in endemic regions.

Abstract: Hypothesis Near-total thyroidectomy, on the basis of its low morbidity rate, is an appropriate treatment option in the surgical management of various thyroid diseases in an endemic region in Turkey. Design Single-institution study of patients with various thyroid diseases treated by means of near-total thyroidectomy within 2 years in an endemic region, with comparison of the results vs the complication rates of bilateral subtotal and total thyroidectomy reported in the literature. Setting Tertiary academic referral center. Patients One hundred fifty-two patients who underwent near-total thyroidectomy for various thyroid diseases. Main Outcome Measures Surgical treatments of various benign thyroid diseases were compared according to the complication rates and the achievable benefits of the procedures. Results In our clinic, near-total thyroidectomy was the principal surgical procedure performed for benign thyroid disease. The temporary recurrent laryngeal nerve palsy rate with respect to the nerves at risk was 3.3% (10 of 304 nerves), whereas temporary hypoparathyroidism was 7.2% (11 of 152 patients). Neither permanent recurrent laryngeal nerve palsy nor permanent hypoparathyroidism occurred. In 1 patient, wound hematoma developed and required re-exploration. Seroma in another patient needed no medical or surgical intervention. Neither wound infection nor mortality were noted. Conclusions Near-total thyroidectomy achieves a lower complication rate of hypoparathyroidism and a similar complication rate of recurrent laryngeal nerve palsy and recurrence when compared with the rates reported in the literature for total thyroidectomy. It is an effective and safe surgical treatment option for various benign thyroid diseases.