Yeşim Erbil

The effect of selenium and/or vitamin E treatments on radiation-induced intestinal injury in rats.

Cytotoxic effects of ionizing radiation on gastrointestinal epithelium may be related to oxidative stress. In this study, we wanted to investigate the effects of selenium, vitamin E and selenium plus vitamin E pretreatments prior to whole abdominal irradiation on intestinal injury. Irradiation caused increased lipid peroxide and decreased GSH levels in the intestine. Intestinal superoxide dismutase and glutathione peroxidase activities were increased, but glutathione transferase activity decreased following irradiation. Selenium and/or vitamin E pretreatments ameliorated these disturbances in prooxidant-antioxidant balance. This amelioriation has been verified with histopathological findings. These results indicate that antioxidant pretreatments prior to irradiation may have some beneficial effects against irradiation-induced intestinal injury.

Evaluation of the Cardiovascular Risk in Patients with Subclinical Cushing Syndrome Before and After Surgery

BackgroundThe widespread use of ultrasound, computerized tomography, and magnetic resonance imaging has led to an increase in the number of incidental adrenal masses identified. Asymptomatic incidentally discovered adrenal masses may indicate that subclinical Cushing syndrome (SCS) is not uncommon. We aimed to evaluate the cardiovascular risk of patients with SCS before and after surgery.MethodsAn autonomous cortisol-producing tumor was detected in 11 of 94 patients with adrenal incidentaloma between 1995 and 2005. Twenty-eight patients suffering from classical Cushing syndrome (CS) associated with unilateral adrenocortical adenoma, who were treated at our department in the same period, served as a control group. Cardiovascular risk factors such as blood pressure, body mass index, and lipid profile were evaluated before and 1 year after surgery.ResultsThe frequency of hypertension (61% versus 63%), obesity (46% versus 55%), diabetes mellitus (50% versus 36%), hypercholesterolemia (39% versus 36%), and low HDL cholesterol (28% versus 36%) were not significantly different between CS and SCS patients, respectively. Adverse cardiovascular risk profile improved 1 year after adrenalectomy in both groups, although the changes were not significant with respect to body mass index, frequency of diabetes, and hyperlipidemia in SCS patients. But frequency of systolic/diastolic hypertension decreased significantly in this group.ConclusionsThese findings indicate that the increased incidence of cardiovascular risk factors commonly observed in classical CS, is also present in SCS. Unilateral adrenalectomy does not always lead to significant improvements in cardiovascular risk profile in SCS.

Impact of Gland Morphology and Concomitant Thyroid Nodules on Preoperative Localization of Parathyroid Adenomas

Objectives: Primary hyperparathyroidism (pHPT) is a common endocrine disease. The aim of this study was to assess the effect of the presence of thyroid nodules, adenoma weight, and ectopic localization on the sensitivity of different imaging studies in patients with hyperparathyroidism.

The impact of age, vitamin D3 level, and incidental parathyroidectomy on postoperative hypocalcemia after total or near total thyroidectomy

BACKGROUND Hypocalcemia caused by transient or definitive hypoparathyroidism is the most frequent complication after thyroidectomy. We aimed to compare the impact of incidental parathyroidectomy and serum vitamin D(3) level on postoperative hypocalcemia after total thyroidectomy (TT) or near total thyroidectomy (NTT). PATIENTS Two hundred consecutive patients with nontoxic multinodular goiter treated by TT and NTT were included prospectively in the present study. Group 1 (n = 49) consisted of patients with a postoperative serum calcium level < or =8 mg/dL, and group 2 (n = 151) had a postoperative serum calcium level greater than 8 mg/dL. Patients were evaluated according to age, preoperative serum 25-hydroxy vitamin D (25-OHD) levels, postoperative serum calcium levels, incidental parathyroidectomy, and the type of thyroidectomy. RESULTS Patients in group 1 (n = 49) were hypocalcemic, whereas patients in group 2 (n = 151) were normocalcemic. Preoperative serum 25-OHD levels in group 1 were significantly lower than in group 2 (P < .001). The incidence of hypoparathyroidism was significantly higher following TT (13.5%) than following NTT (2.5%) (P < .05). The risk for postoperative hypocalcemia was increased 25-fold for patients older than 50 years, 28-fold for patients with a preoperative serum 25-OHD level less than 15 ng/mL, and 71-fold for patients who underwent TT. Incidental parathyroidectomy did not have an impact on postoperative hypocalcemia. The highest risk of postoperative hypocalcemia was found in the patients with all of the above variables. CONCLUSIONS Age, preoperative low serum 25-OHD, and TT are significantly associated with postoperative hypocalcemia. Patients with advanced age and low preoperative serum 25-OHD levels should be placed on calcium or vitamin D supplementation after TT to avoid postoperative hypocalcemia and decrease hospital stay.

Correlations between Vitamin D Status and Biochemical/Clinical and Pathological Parameters in Primary Hyperparathyroidism

BackgroundTo determine the prevalence of vitamin D deficiency and the effects of vitamin D status on parathyroid adenoma weight, clinical and biochemical indices in patients with primary hyperparathyroidism (pHPT) were studied.MethodsEighty patients with pHPT who underwent surgical treatment and in whom the presence of parathyroid adenoma were confirmed histopathologically were studied retrospectively from recorded data files. Patients were divided into three groups: patients with 25-hydroxyvitamin D (25-OHD) concentrations < 15 ng/ml (group 1, n = 44), patients with 25-OHD concentrations > 15–25 ng/ml (group 2, n = 9), and patients with 25-OHD concentrations > 26 ng/ml (group 3, n = 27). Serum calcium, phosphate, alkaline phosphatase, creatinine, and albumin levels and urinary calcium excretion were determined by auto-analyzer. Plasma 25-OHD and parathyroid hormone (PTH) levels were determined by immunoradiometric assay using commercially available kits.ResultsNo statistically significant differences were observed with respect to serum calcium, phosphorus, albumin, and creatinine concentrations between these groups. Serum PTH, alkaline phosphatase concentrations, urinary calcium excretion, parathyroid adenoma weight, and postoperative sixth month PTH concentrations were significantly higher in group 1 patients than in group 2 and group 3 patients. Significant correlations were observed between parathyroid adenoma weight and serum 25-OHD concentrations (r = −0.348, P = 0.020); parathyroid adenoma weight and urinary calcium excretion (r = 0.348, P = 0.021). Multiple regression analysis revealed that parathyroid adenoma weight, serum 25-OHD, and preoperative PTH concentrations correlated independently and significantly with postoperative sixth month PTH concentrations.ConclusionsVitamin D deficiency leads to more severe bone disease, increased parathyroid tumor growth, and delayed postoperative recovery of parathyroid function in patients with primary hyperparathyroidism.

Surgical Management of Substernal Goiters: Clinical Experience of 170 Cases

PurposeTo discuss the presentation, diagnosis, treatment, histopathological findings, and complications of patients who underwent thyroidectomy for substernal goiter in our surgical clinic.MethodsWe retrospectively analyzed 170 patients with substernal goiters among 2650 patients undergoing surgical treatment for various thyroid diseases between 1990 and 2003. We evaluated the clinical data, preoperative diagnostic findings, surgical treatments, histopathological results, and postoperative complications.ResultsThe most common symptoms were a cervical mass (88%) and dyspnea (35%), but 26% of the patients were asymptomatic. Chest radiography provided the first evidence of a substernal goiter in 77% of the patients. We performed total or near total thyroidectomy and operated through a cervical incision in all but 12 of the patients. There was no operative mortality but 12 (7%) patients suffered temporary hypoparathyroidism and 4 suffered transient vocal cord paralysis (2%). Malignancy was diagnosed by histopathological examination in 22 (13%) patients.ConclusionWe think that the diagnosis of a substernal goiter is an indication for thyroidectomy, which is associated with very low postoperative morbidity.

Evaluation of recurrent laryngeal nerve monitoring in thyroid surgery

AIM Thyroidectomy creates a potential risk for all parathyroid glands and nerves. Nerve identification has decreased the rates of nerve injury during thyroidectomy. Intraoperative nerve monitoring (IONM) has been used as an adjunct to the visual identification of the nerve. The aim of this clinical trial is to evaluate the effect of the identification time of RLN during thyroidectomy using IONM. METHOD Two hundred and thirty seven patients and 409 nerves at risk were enrolled in this prospective study. The nerves in Group 1 (n=210) were identified with IONM, whereas the nerves in Group 2 (n=199) were identified without IONM. RESULT The identification time of RLN and the operating time in patients of Group 1 were significantly lower than patients of Group 2. There was not any significant difference between postoperative complications of the groups. According to logistic regression analysis, the use of IONM was found to be the only determinant of the decrease of identification time of RLN. CONCLUSION Although the operating time was lower with IONM than with visualization alone, the shortened surgical time may not seem to have great clinical relevance. However, the shorter the nerve is identified the lower is the surgeons level of stress. We think that it is important to use IONM to decrease the identification time of RLN in the course of thyroidectomy.

Do Vitamin E and Selenium Have Beneficial Effects on Trinitrobenzenesulfonic Acid-Induced Experimental Colitis

The balance between oxidant and antioxidant systems may be important in the pathogenesis and/or maintenance of tissue injury in ulcerative colitis. This study was designed to evaluate the effects of vitamin E and selenium supplementations on tissue injury and oxidative stress in trinitrobenzenesulfonic acid-induced ulcerative colitis in rats. Trinitrobenzenesulfonic acid administration severely changed the normal architecture of the colon and significantly increased the levels of malondialdehyde, protein carbonyl, and xantine oxidase (P < 0.001) in the colon homogenates of these rats. Supplementation of selenium to the trinitrobenzenesulfonic acid-treated rats neither improved the histopathological findings nor decreased the levels of malondialdehyde and protein carbonyl. Vitamin E supplementation reduced the levels of malondialdehyde and protein carbonyl but did not improve the colonic lesions. Supplementation of vitamin E+selenium significantly reduced both the severity of colonic lesions and the levels of malondialdehyde and protein carbonyl. In conclusion, we suggest that antioxidants and specific micronutrients may have beneficial effects in the treatment of ulcerative colitis.

Determinants of postoperative hypocalcemia in vitamin D–deficient Graves’ patients after total thyroidectomy

BACKGROUND The etiology of postoperative hypocalcemia after total thyroidectomy appears to be multifactorial, that is, postoperative transient hypoparathyroidism, low 25-hydroxy vitamin D (25-OHD) concentrations, aging, and hyperthyroidism with increased bone turnover. Our aim was to evaluate the factors responsible for postoperative hypocalcemia in euthyroid vitamin D-deficient/insufficient Graves patients who underwent total thyroidectomy at our institution. METHODS Thirty-five consecutive patients with Graves disease treated by total thyroidectomy were included in the present study. All patients were vitamin D deficient/insufficient (ie, 25-OHD concentrations of <20/<30 ng/mL, respectively). Patients were divided into 2 groups according to postoperative serum albumin corrected calcium concentrations: group 1 (n = 13) patients had postoperative serum calcium concentrations of 8 mg/dL or less; group 2 (n = 22) patients had serum calcium concentrations greater than 8 mg/dL. Bone turnover markers (deoxypiridinoline, bone-specific alkaline phosphatase) and 25-OHD were determined the day before surgery. RESULTS In group 1 patients, disease duration was significantly longer, 25-OHD and postoperative parathyroid hormone concentrations were significantly lower, and bone turnover markers were significantly higher. Logistic regression analysis revealed that a postoperative parathyroid hormone concentration less than 10 pg/mL was the most powerful parameter to predict postoperative hypocalcemia (odds ratio, 23; 95% confidence interval, 3.3-156). CONCLUSIONS In Graves patients with vitamin D deficiency/insufficiency, postoperative (transient) hypoparathyroidism is the most significant parameter to determine the development of postoperative hypocalcemia.

Lipid Peroxidation and Antioxidant State after Laparoscopic and Open Cholecystectomy

OBJECTIVE To measure the amount of lipid peroxidation and erythrocyte antioxidation in patients undergoing laparoscopic and open cholecystectomy and healthy controls. DESIGN Non-randomised study. SETTING University hospital, Istanbul. SUBJECTS 31 patients, of whom 14 underwent open and 17 laparoscopic cholecystectomy, and 15 healthy controls. INTERVENTIONS Heparinised blood samples were taken from the patients immediately after operation and from the healthy controls. MAIN OUTCOME MEASURES Lipid peroxidation index as expressed by thiobarbituric-acid-reactive substances (TBARS) and components of the erythrocyte antioxidant defence system, namely reduced glutathione, reduced glutathione peroxidase (glutathione-Px) and CuZn superoxide dismutase (CuZn SOD) in patients undergoing open or laparoscopic cholecystectomy and healthy controls. RESULTS All 4 variables were significantly higher in the cholecystectomy groups than in controls (p < 0.001), and laparoscopic cholecystectomy caused significantly less oxidative stress than the open operation (p < 0.001). CONCLUSION Both types of cholecystectomy cause oxidative stress and lead to an adaptive antioxidant response in the body. However; both oxidative stress and the antioxidant response are more pronounced after traditional open cholecystectomy.