Ozlem Gulbahar

Evaluation of Bone Turnover in Epileptic Children Using Oxcarbazepine

This study evaluated the effects of oxcarbazepine monotherapy on bone turnover in prepubertal and pubertal children. Thirty-four newly diagnosed pediatric patients with normal bone mineral density, serum biochemical markers of bone formation, and hormonal markers participated. Levels of 25-hydroxyvitamin D were significantly decreased after therapy compared with baseline values. Levels of gamma-glutamyl transferase, phosphorus, alkaline phosphatase, osteocalcin, parathyroid hormone, and calcitonin had increased. However, only changes in osteocalcin and gamma-glutamyl transferase levels were statistically significant compared with baseline values. Drug-induced osteopenia was evident in 3 patients with z scores of bone-mineral density less than -2.0, whereas these patients had z scores of less than -1.5 before treatment. Although 18 months of oxcarbazepine treatment exerted slightly adverse effects on bone metabolism, the effect seems insignificant in children with normal bone-mineral density. Although alterations in bone metabolism do not always suffice to explain the decrease in bone-mineral metabolism, we think that patients with osteopenia before the initiation of oxcarbazepine therapy should be followed carefully, especially in long-term treatment.

Neuroprotective effects of infliximab in experimental spinal cord injury

BACKGROUND The aim of the study is to assess the effects of infliximab, a TNF-alpha receptor blocker, in a spinal cord clip compression injury model. METHODS Clip compression injury model was used for producing spinal cord injury on 32 adult, male Wistar rats (Gazi University Animal Research Laboratory, Ankara, Turkey). After exposing the vertebral column between T7 and T10, total laminectomy was performed with the assistance of a high-speed drill and a surgical microscope. The dura was left intact. Spinal cord injury was performed on all rats with application of a 70-g closing force aneurysm clip for 1 minute. The rats were randomly allocated into 4 groups. Control group received no further therapy, whereas the other 3 groups received methylprednisolone (30 mg/kg intraperitoneal), infliximab (5 mg/kg subcutaneous), and a mixture of these 2 agents. All rats were killed 72 hours later, and the level of lipid peroxides in traumatized spinal cord tissue were measured as thiobarbituric acid-reactive material and determined using the method of Mihara and Uchiyama (Determination of malonaldehyde precursor in tissue by thiobarbituric acid test. Anal Biochem 1978;86(1):271-8). RESULTS Treatment with infliximab and methylprednisolone decreased MDA levels in rats with spinal cord injury with a statistically significant difference. In addition, combined therapy achieved a more profound decrease in tissue MDA levels, which was also statistically significant. CONCLUSIONS Infliximab is found as effective as methylprednisolone on spinal cord clip compression injury. Moreover, the combination of these 2 agents demonstrated higher efficacy suggesting a synergistic effect between these 2 agents. However, further studies regarding functional and behavioral analyses as well as biochemical markers are required.

A comparison of epidural and paravertebral catheterisation techniques in post-thoracotomy pain management

BACKGROUND Thoracotomy is a surgical procedure associated with severe pain. Operative morbidity rates reduce by effective postoperative pain control. The aim of this study is to compare the effectiveness of the thoracic epidural blockade (TEB) and the paravertebral blockade (PVB) methods in relieving the pain caused by a thoracotomy incision. MATERIALS AND METHODS We studied 44 consecutive patients who underwent elective posterolateral thoracotomy. The patients were classed into two groups: TEB (n=19) and PVB (n=25). Patients in both the groups could self-control the infusion of bupivacaine infusion and diclofenac sodium. The groups were compared according to the parameters such as analgesic efficacy (VAS), respiratory function tests (forced expiratory volume in 1s (FEV(1)), peak expiratory flow rate (PEFR) and arterial blood gases), stress response (serum cortisol and glucose levels), adverse effects, necessity for additional analgesia, duration of catheter application procedure, mean hospital stay and postoperative follow-up. Results are analysed statistically by Mann-Whitney U, Wilcoxon, chi-square and Fishers exact tests, and a p-value of <0.05 was accepted to be statistically significant. RESULTS There was no significant difference between the two groups with regard to age, gender, VAS, FEV(1), PEFR, serum cortisol and glucose levels, necessity for additional analgesia and hospital staying days. In contrast, adverse effects and duration of catheterisation were statistically significantly lower in group PVB (p=0.001 and p<0.001, respectively). CONCLUSION PVB catheterisation can be easily performed and placed in a short span perioperatively. Therefore, it might be the preferred method over TEB which has a high incidence of adverse effects and complication rates.

Mitomycin C decreases the rate of stricture formation in caustic esophageal burns in rats

BACKGROUND Although the incidence of caustic ingestion is declining, the management of caustic esophageal strictures remains a challenge. Although many agents have been tried experimentally to treat strictures, few have gained clinical application. The aim of this study was to investigate the influence of mitomycin C (MMC), which inhibits fibroblastic proliferation in treating delayed caustic esophageal strictures. METHODS Forty-two rats were allocated into 3 groups. Caustic esophageal burns were created as described by Gehanno. Group A was instilled only with saline. Group B was injured with 10% NaOH and left untreated. Group C was injured and received topical MMC at 0.04% concentration in the fourth week. At 56 days, stenosis index (SI), collagen deposition, and hydroxyproline content (HP) were determined in distal esophageal segments. Statistical analyses were performed. RESULTS The mean SI in group B was significantly higher than others (SI: 1.15 +/- 0.37 d/lum, P < .05). Collagen accumulation was highest in group B, followed by groups C and A, respectively. Collagen deposition in group C was statistically lower than group B (P < .018). The mean HP in group B was statistically higher than others (5.07 +/- 1.30 microg/mg tissue, P < .05), and similar between groups A and C (1.20 +/- 0.20, 1.91+/- 0.79, respectively, P = .73). CONCLUSION In the current study, MMC treatment ameliorated caustic esophageal stricture as reflected in the significantly lower SI. We conclude that MMC application is effective in the treatment of caustic esophageal strictures.

Consequences of hypoxia-reoxygenation phenomena in patients with obstructive sleep apnea syndrome.

Background and Objectives : Obstructive sleep apnea syndrome (OSAS) is a common disorder characterized by numerous episodes of absence of respiratory flow during sleep, which can be followed by a decrease in SaO2 , which is rapidly normalized when ventilation resumes. We hypothesize that this hypoxia-reoxygenation phenomena may affect the generation of vascular endothelial growth factor (VEGF), erythropoietin (EPO), endothelin-1 (ENDO-1), and inducible nitric oxide synthase (iNOS). Design and Setting : Prospective, patients referred to sleep disorders center. Patients and Methods : The presence and severity of OSAS were determined using the standard overnight polysomnography. Diagnosis of OSAS was made when the apnea-hypopnea index (AHI) was ≥15, independent of the appearance of symptoms. Serum levels of VEGF, EPO, ENDO-1, and nitrite-nitrate were measured after overnight fasting in 69 patients with OSAS and in 17 healthy control subjects. Serum levels of VEGF and nitrite-nitrate were measured again after 12 weeks of treatment with continuous positive airway pressure (CPAP) in OSAS patients. Results : Serum VEGF levels were found to be significantly higher and nitrite-nitrate levels were found to be significantly lower in OSAS patients than in controls (P=.003, .008, respectively), but no differences in EPO and ENDO-1 levels were found between the groups. We demonstrated that in OSAS patients, the serum VEGF levels were decreased and nitrate levels were increased after 12 weeks of CPAP treatment (P=.001, .002, respectively). Conclusion : According to our data, it is likely that hypoxia-reoxygenation phenomena affect the VEGF and nitrite-nitrate levels, which may be pathogenic factors in generating cardiovascular complications in OSAS.

A Case With Immunoassay Interferences in the Measurement of Multiple Hormones

CONTEXT Commonly used immunoassays are not free from interference, which can be a confounder in the interpretation of test results. We present a case with extremely high multiple hormone levels due to such interference. CASE DESCRIPTION A 33-year-old woman with no specific symptoms had markedly elevated TSH with normal free T4 and free T3 levels. Repeated measurements revealed discordantly high TSH, ACTH, FSH, PTH, IGF-1, prolactin, β-human chorionic gonadotropin, and calcitonin levels without the associated clinical pictures. The measurements were repeated with the same patient sample on four different analytical platforms using chemiluminescence immunoassays/electrochemiluminescence immunoassays, and the results were divergent on each platform. Serial dilutions of serum samples revealed nonlinearity, suggesting assay interference. All hormonal measurements were in the normal range when heterophile antibody blocking tubes were used. The serum of the patient was then subjected to polyethylene glycol precipitation. The post-polyethylene glycol recovery resulted in hormone levels in the normal range. The patient did not receive any medications and has been under follow-up without any signs and symptoms for 24 months. CONCLUSIONS This report illustrates a rare case of falsely elevated hormone levels due to assay interference caused by heterophile antibodies. We point out the importance of a close collaboration between clinicians and the laboratory to avoid unnecessary clinical investigations as well as inappropriate treatments.

Prophylactic Drugs and Cytokine and Leptin Levels in Children With Migraine

The study objective was to evaluate levels of the cytokines tumor necrosis factor alpha, interleukin-1beta, and interleukin-6 and of leptin, and then to determine the relationship between these levels and clinical responses in children with migraine after prophylactic therapy with one of four drugs. In all, 77 children who needed prophylactic drugs were treated with cyproheptadine, amitriptyline, propranolol, or flunarizine. Serum levels of the cytokines and leptin were measured before and 4 months after the treatment. Results were compared by drug for headache frequency, severity, and duration, the PedMIDAS score, and levels of each cytokine and of leptin. Each of the four drugs not only decreased the frequency and duration but also the severity of headache, and the PedMIDAS score. None of the drugs was found to be superior to others in terms of reduction in cytokine levels (P > 0.05). Both cyproheptadine and flunarizine (but not amitriptyline and propranolol) caused an increase in leptin levels (P < 0.05). These data suggest that cytokine levels are related to clinical responses, and might help in objective evaluation of clinical response in migraine. To our knowledge, the present study is the first trial to compare the effects of prophylactic drugs, cytokine levels, and leptin levels in children with migraine.

The effects of iloprost, a prostacyclin analogue, in experimental ischaemia/reperfusion injury in rat ovaries

Ovarian torsion is a surgical emergency affecting not only the ipsilateral ovary but also contralateral ovary. Although the conventional treatment is salpingo-oophorectomy, recent studies advocate detorsion. We hypothesized that iloprost, an analogue of prostacyclin with cytoprotective properties, may prevent the harmful effects of ischaemia-reperfusion injury in bilateral ovaries after unilateral ovarian torsion-detorsion in rat. In this study, 24 female Wistar-albino female rats were divided into four groups. Ovarian torsion was produced by applying vascular clamps to right ovaries. In Group I, bilateral oophorectomy was performed. In group II, bilateral oophorectomy was performed after a unilateral torsion period of 4h. In group III, bilateral ovaries were removed, following unilateral torsion-detorsion periods each lasted for 4h. Saline was injected i.p. 30 min before detorsion. In group IV, same experimental protocol, which was conducted in group III, was repeated. Iloprost was injected i.p. 30 min before detorsion instead of saline in group IV. Tissue levels of malondialdehyde (MDA) and nitric oxide (NO), which are the indicators for oxidative stress were determined and histopathological evaluation was performed in bilateral ovaries in all groups. The MDA and NO levels for ipsilateral ovaries of four groups were compared and no significant difference was found (p>0.05). The same comparison were done for the contralateral sides and no difference was seen either (p>0.05). In histological examination, iloprost produced improvement in I/R-induced alterations in ipsilateral and contralateral ovaries. In conclusion, these results showed that iloprost has beneficial effect on the histological appearances in both the ipsilateral and contralateral rat ovaries after unilateral torsion-detorsion.

Maternal cardiac risks in pre-eclamptic patients

Objective: To investigate the relationship between pre-eclampsia (PE) and maternal cardiac risk factors. Material-methods: A total of 41 pregnant women were included in this study. Patient groups consisted of 25 PE patients and 16 normal pregnant women as a control group. We measured the serum total cholesterol, high-density lipoprotein cholesterol (HDL-C), triglyceride (TG), homocystein, apoprotein A1, apoprotein B100, lipoprotein (a), high sensitivity C-reactive protein (hsCRP), cystatin C levels as cardiac risk factors. Serum low-density lipoprotein (LDL) and very low density lipoprotein (VLDL) cholesterol levels were calculated using Friedwald equation. Results: The levels of TG, LDL-C, homocysteine, apoprotein B100 and cystatine C were higher in the PE patients than those in the control group (p < 0.05). HDL-C and apolipoprotein’s AI levels were lower than those of normotensive pregnants (p < 0.05). HsCRP levels were also higher in the patient group but the difference was not statistically significant. Conclusion: PE is an important and as yet, incompletely understood disorder of pregnancy. Our study showed that the blood levels for some cardiac risk factors were increased in women with PE, which may contribute to its multisystem pathology. Consideration should be given to monitoring women with PE for these cardiac risk factors in pre-eclamptic women both during pregnancy, as well as later in life.

Neuroprotective effects of gabapentin in experimental spinal cord injury.

BACKGROUND Extensive research has focused on neuroprotection after spinal cord trauma to alleviate the effects of secondary injury. This study aims to investigate the neuroprotective effects of gabapentin in experimental spinal cord injury. METHODS Thirty-six adult, male Wistar rats received spinal cord injury using the clip compression method. Animals were divided into five groups. High (200 mg/kg) and low doses (30 mg/kg) of gabapentin were administered to the animals in the treatment groups after spinal cord trauma and ultrastructural findings and lipid peroxidation levels of these two groups were compared with the animals that received only laminectomy, only trauma, and trauma and 30 mg/kg methylprednisolone. RESULTS Regarding tissue lipid peroxidation levels after trauma, animals in gabapentin groups demonstrated better results than the trauma group. However, these results were no better than the methylprednisolone group. The results regarding the ultrastructural findings were similar. Treatment groups demonstrated better ultrastructural findings than the trauma group. In addition, the results of the high dose gabapentin group were significantly better than the low dose gabapentin group. CONCLUSIONS Gabapentin demonstrated similar neuroprotective effects as methylprednisolone in early phase of spinal cord injury. Further studies with different experimental settings including neurological outcome are required to achieve conclusive results.