Retinal ganglion cell toxicity due to oxcarbazepine and valproic acid treatment in rat

PurposeTo evaluate and to compare the possible toxic effects of oxcarbazepine (OXC) and valproic acid (VPA) on retinal ganglion cells (RGCs) in rat.MethodsForty female Wistar rats (21–24 days old and weighted between 44.6 and 57.3 g) were divided equally into 4 experimental groups which were applied tap water (group 1), 300 mg/(kg day) VPA (group 2), 100 mg/(kg day) OXC (group 3), and both VPA and OXC (group 4) via gavage for 90 days. Enucleation was performed for histopathologic analysis. RGCs were counted under the light microscopic examination.ResultsRGC numbers in OXC and combined OXC-VPA groups were found to be lower than those of control group. On the other hand RGC number was comparable with those of control group in VPA group.ConclusionOXC seems to be toxic to RGCs at 100 mg/kg dose when it is been given as a monotherapy or combined with VPA. Single VPA treatment has no effect on RGC number.     

Comparison of iodine-125 plaque brachytherapy and gamma knife stereotactic radiosurgery treatment outcomes for uveal melanoma patients

Graefe's Archive for Clinical and Experimental Ophthalmology - To compare the efficacies of iodine-125 brachytherapy (IBT) and gamma knife stereotactic radiosurgery (GKRS) in the treatment of...     

From a branchial fistula to a branchiootorenal syndrome: a case report and review of the literature

Branchial abnormalities constitute 32% to 45% of all neck pathologies in children. They may be a part of branchiootorenal (BOR) syndrome, which is characterized by branchial arch anomalies, preauricular pits, hearing impairment, and renal malformations. Typically, the management of a branchial fistula does not necessarily require an extensive diagnostic workup. However, in patients with a branchial fistula associated with external ear anomalies on physical examination and/or a history of hearing loss and a similar history and findings in other family members, an additional workup should be performed to eliminate the possibility of BOR syndrome. The aim of this report is to make pediatric surgeons aware of the BOR syndrome in patients presenting with branchial arch anomalies.     

Comparison of pure tone audiometry and auditory steady-state responses in subjects with normal hearing and hearing loss

The objective of this study is to compare pure tone audiometry and auditory steady-state response (ASSR) thresholds in normal hearing (NH) subjects and subjects with hearing loss. This study involved 23 NH adults and 38 adults with hearing loss (HI). After detection of behavioral thresholds (BHT) with pure tone audiometry, each subject was tested for ASSR responses in the same day. Only one ear was tested for each subject. The mean pure tone average was 9 ± 4 dB for NH group and 57 ± 14 for HI group. There was a very strong correlation between BHT and ASSR measurements in HI group. However, the correlation was weaker in the NH group. The mean differences of pure tone average of four frequencies (0.5, 1, 2, and 4 kHz) and ASSR threshold average of same frequencies were 13 ± 6 dB in NH group and 7 ± 5 dB in HI group and the difference was significant (P = 0.01). It was found that 86% of threshold difference values were less than 20 dB in NH group and 92% of threshold difference values were less than 20 dB in HI group. In conclusion, ASSR thresholds can be used to predict the configuration of pure tone audiometry. Results are more accurate in HI group than NH group. Although ASSR can be used in cochlear implant decision-making process, findings do not permit the utilization of the test for medico-legal reasons.     

Evaluation of Dysphagia in Early Stroke Patients by Bedside, Endoscopic, and Electrophysiological Methods

We aimed in this study to evaluate dysphagia in early stroke patients using a bedside screening test and flexible fiberoptic endoscopic evaluation of swallowing (FFEES) and electrophysiological evaluation (EE) methods and to compare the effectiveness of these methods. Twenty-four patients who were hospitalized in our clinic within the first 3 months after stroke were included in this study. Patients were evaluated using a bedside screening test [including bedside dysphagia score (BDS), neurological examination dysphagia score (NEDS), and total dysphagia score (TDS)] and FFEES and EE methods. Patients were divided into normal-swallowing and dysphagia groups according to the results of the evaluation methods. Patients with dysphagia as determined by any of these methods were compared to the patients with normal swallowing based on the results of the other two methods. Based on the results of our study, a high BDS was positively correlated with dysphagia identified by FFEES and EE methods. Moreover, the FFEES and EE methods were positively correlated. There was no significant correlation between NEDS and TDS levels and either EE or FFEES method. Bedside screening tests should be used mainly as an initial screening test; then FFEES and EE methods should be combined in patients who show risks. This diagnostic algorithm may provide a practical and fast solution for selected stroke patients.     

Dose-dependent ultrastructural changes in rat cornea after oral methylphenidate administration

OBJECTIVE: To investigate dose-dependent ultrastructural changes in rat cornea after oral methylphenidate Ritalin administration. METHODS: This study was conducted in the Department of Anatomy, Gazi University Faculty of Medicine, Ankara, Turkey between March and May 2005, with a total of 27 female prepubertal Wistar albino rats, divided into 3 different dose groups 5mg/kg, 10 mg/kg, 20 mg/kg, and their control groups. They were treated orally with methylphenidate, and eye tissue was removed to process for electron microscopic studies. RESULTS: We observed that all cells, and prominently basal cells of the corneal epithelium show dose-dependent degenerative changes such as apoptotic bodies, chromatin condensation, and ondulation in their nuclei and crystolysis of the mitochondrion. In the stroma, the most evident finding was the increase of the collagen fiber. In addition to dose-dependent changes related to the apoptotic process, which is chromatin condensation in their nuclei, electron dense material accumulation, and pericellular edema in the cytoplasm were also seen. In the endothelial cell lines, disruption of the junctional complexes, vacuolization in the cell cytoplasms, and crystolysis of the mitochondrion's with rough endoplasmic reticulum cisternae activity were observed. CONCLUSION: Ritalin is inducing an evident degeneration, especially in epithelium cells with increasing doses. Ultrastructural cell organelle composition degeneration with stromal fibrosis has a negative effect on cornea dehydration. In light of these findings, we believe that the Ritalin treatment doses need to be kept to a minimum to maintain healthy cornea ultrastructure and related physiology.     

The treatment of segmental bone defects in rabbit tibiae with vascular endothelial growth factor (VEGF)-loaded gelatin/hydroxyapatite “cryogel” scaffold

The aim of this study was to investigate the effectiveness of a novel hydroxyapatite containing gelatin scaffold—with and without local vascular endothelial growth factor (VEGF) administration—as the synthetic graft material in treatment of critical-sized bone defects. An experimental nonunion model was established by creating critical-sized (10 mm. in length) bone defects in the proximal tibiae of 30 skeletally mature New Zealand white rabbits. Following tibial intramedullary fixation, the rabbits were grouped into three: The defects were left empty in the first (control) group, the defects were grafted with synthetic scaffolds in the second group, and synthetic scaffolds loaded with VEGF were administered at bone defects in the third group. Five rabbits in each group were killed on 6th and 12th weeks, and new bone growth was assessed radiologically, histologically and with dual-energy X-ray absorptiometry (DEXA). At 6 weeks, VEGF-administered group had significantly better scores than the other two groups. The second group also had significantly better scores than the control group. At 12 weeks, while no significant difference was noted between the second and third groups, these two groups both had significantly better scores in all criteria compared with the control group. There were no signs of complete fracture healing in the control group. The administration of hydroxyapatite containing gelatin scaffold yielded favorable results in grafting the critical-sized bone defects in this experimental model. The local administration of VEGF on the graft had a positive effect in the early phase of fracture healing.