Göksemin Acar

Influence of Tribulus terrestris extract on lipid profile and endothelial structure in developing atherosclerotic lesions in the aorta of rabbits on a high-cholesterol diet☆

The aim of this study was to investigate the pleotropic effects of an extract of a traditional herb, Tribulus terrestris (TT), on the lipid profile and vascular endothelium of the abdominal aorta in New Zealand rabbits fed a cholesterol-rich diet. Eighteen rabbits were randomly divided into three groups (n=6 for each). One experimental group (EG-I) was given a cholesterol-rich diet, a second experimental group (EG-II) was treated with TT following a cholesterol-rich diet, and a control group (CG) was fed a standard diet. Blood samples were collected on day 0 and then at weeks 4 and 12 to determine total serum cholesterol (TC), high density lipid-cholesterol (HDL-C), low density lipid-cholesterol (LDL-C) and triglyceride (TG) levels. Tissues were collected from the abdominal aorta for immunohistochemistry and transmission and scanning electron microscopy. In EG-II, the serum lipid profile was significantly lower than that of EG-I at week 12 with a reduction of TC: 65%; LDL-C: 66%; HDL-C: 64%; TG: 55%. Ultrastructural analysis revealed that endothelial damage was more prominent in EG-I compared to EG-II. The ruptured endothelial linings and damaged cellular surfaces increased in EG-I compared to EG-II. Our data indicate that dietary intake of TT can significantly lower serum lipid profiles, decrease endothelial cellular surface damage and rupture and may partially repair the endothelial dysfunction resulting from hyperlipidemia.

Seizure Outcome following Transcortical Selective Amygdalohippocampectomy in Mesial Temporal Lobe Epilepsy

The aim of this study was to retrospectively determine if patients with medically refractory epilepsy, due to hippocampal sclerosis, who underwent selective amygdalohippocampectomy (SAH) with a transcortical approach experienced improved seizure outcome. Thirty-nine patients with mesial temporal lobe epilepsy and hippocampal sclerosis were included in the study. The mean follow-up was 25.88 ± 17.69 months. Antiepileptic medication use and seizure frequency were significantly reduced after SAH. After surgery, 32 patients (82.05%) were completely seizure free (Engel class IA), and 2 patients experienced transient memory difficulty. In conclusion, SAH with a transcortical approach can lead to favorable seizure control with a low irreversible complication risk.

Effects of the hippocampal deep brain stimulation on cortical epileptic discharges in penicillin - induced epilepsy model in rats.

AIM Experimental and clinical studies have revealed that hippocampal DBS can control epileptic activity, but the mechanism of action is obscure and optimal stimulation parameters are not clearly defined. The aim was to evaluate the effects of high frequency hippocampal stimulation on cortical epileptic activity in penicillin-induced epilepsy model. MATERIAL AND METHODS Twenty-five Sprague-Dawley rats were implanted DBS electrodes. In group-1 (n=10) hippocampal DBS was off and in the group-2 (n=10) hippocampal DBS was on (185 Hz, 0.5V, 1V, 2V, and 5V for 60 sec) following penicillin G injection intracortically. In the control group hippocampal DBS was on following 8 μl saline injection intracortically. EEG recordings were obtained before and 15 minutes following penicillin-G injection, and at 10th minutes following each stimulus for analysis in terms of frequency, amplitude, and power spectrum. RESULTS High frequency hippocampal DBS suppressed the acute penicillin-induced cortical epileptic activity independent from stimulus intensity. In the control group, hippocampal stimulation alone lead only to diffuse slowing of cerebral bioelectrical activity at 5V stimulation. CONCLUSION Our results revealed that continuous high frequency stimulation of the hippocampus suppressed acute cortical epileptic activity effectively without causing secondary epileptic discharges. These results are important in terms of defining the optimal parameters of hippocampal DBS in patients with epilepsy.

Deep Brain Stimulation of the Pedunculopontine Nucleus in a Patient with Freezing of Gait

Case Presentation: A 54-year-old male patient presenting probable multiple system atrophy with predominant parkinsonism who underwent bilateral deep brain stimulation (DBS) of the pedunculopontine nucleus (PPN) is presented. The patient had dominant freezing of gait (FOG), levodopa-resistant bradykinesia, and autonomic disturbances, but with a good cognitive condition. Methods: The patient underwent bilateral DBS of the PPN, which ended with modest benefits. Results and Conclusion: Although he had a short postoperative follow-up (6 months), his neurological status remained stable and PPN DBS provided modest improvements in the gait disorder and freezing episodes. This unusual case suggests that the mesencephalic pedunculopontine region may have a role in locomotor symptoms and the potential to provide a limited improvement in FOG.

Manic episode following deep brain stimulation of the subthalamic nucleus for Parkinson's disease: a case report.

AIM Deep brain stimulation (DBS) of the subthalamic nucleus (STN) is an established therapy for patients with Parkinsons disease (PD) associated with motor complications of long term L-dopa treatment. MATERIAL AND METHODS Here we report two cases with DBS- induced manic episode, focusing on the functional and anatomic correlates of psychiatric adverse effects of STN stimulation. RESULTS We present two cases of PD with motor complications due to long term L-dopa treatment that developed their first episodes of mania with psychotic symptoms after bilateral STN-DBS implantation. DBS-induced psychiatric adverse effects may be attributable either to limbic connections and STN-specific oscillations or stimulation of the medial forebrain bundle.

Effect of Subthalamic Nucleus Stimulation on Pedunculopontine Nucleus Neural Activity

Background: The pedunculopontine nucleus has recently been proposed as an alternative target for deep brain stimulation for the treatment of medically intractable Parkinsons disease. The suggested indication for pedunculopontine nucleus deep brain stimulation is severe and medically intractable axial symptoms such as gait and postural impairment. Objective: Our goal in this study was to describe the effects of subthalamic nucleus stimulation on pedunculopontine nucleus electrophysiological activity. Methods: Fourteen male Wistar rats were divided into a sham stimulation group and an experimental group. In both groups, electrodes were implanted bilaterally into the subthalamic nucleus and into the right pedunculopontine nucleus. Microelectrode recordings were carried out in both groups prior to and during subthalamic nucleus stimulation. Results: Subthalamic nucleus stimulation produced no clear inhibition of neuronal firing in the pedunculopontine nucleus. However, we found that stimulation of the subthalamic nucleus at 60 Hz produces some entrainment of pedunculopontine nucleus neuronal firing and a shift of subthalamic nucleus firing patterns to more tonic and random patterns. These results are consistent with the effects of deep brain stimulation on neuronal activity in the subthalamic nucleus and globus pallidus internus. Conclusion: The result of this study provides additional evidence to improve our understanding of the mechanism of subthalamic nucleus-deep brain stimulation, and its physiological consequences.

A case report of surgically treated drug resistant epilepsy associated with subependymal nodular heterotopia

Subependymal nodular heterotopia (SNH) is a cortical development malformation that is commonly associated with medically resistant epilepsy. Cases of SNH are challenging to treat surgically because there are typically multiple nodules, which may be involved in epileptogenesis. Moreover, dual pathology may exist in these patients. Here, we present a case with unilateral subependymal heterotopic nodules associated with ipsilateral hippocampal atrophy. Invasive and non-invasive work-ups revealed that the hippocampus was the actual ictal onset zone and that the SNH was not involved. An anterior temporal lobectomy was carried out, and postoperative seizure outcome was class Ia at the end of 2 years. The case demonstrates that SNH may not play a major role in patients with dual pathology. However, direct electroencephalography (EEG) recording from areas of SNH and other possible epileptogenic regions is indispensable in defining the ictal onset zone and avoiding poor surgical outcomes.

Demographic and historical backgrounds of the elderly with nonepileptic seizures: A comparative study

BACKGROUND Non-epileptic seizures (NES) are not infrequent in the elderly. However, the data on NES in the elderly is likited. AIM To study the demographic and historical background of eldely patients with NES and compare the same with the data in the younger patients with NES. MATERIALS AND METHODS Patients with NES over 55 years of age and the next two consecutive patients with NES between ages 18 and 45 were compared in terms of demographic and historical features, psychiatric evaluation and MMPI testing. RESULTS Of all the 128 patients with NES, 13 (10.6%) were over 55 years of age. History of physical/sexual abuse was high in both the groups. The mean length of time for NES diagnosis was longer in the elderly (13.38 +/- 15.33 vs. 6.15 +/- 8.04 years; P < 0.05). Majority of the patients with NES were on AEDs without evidence of epilepsy and almost half in both the groups were using benzodiazepines. CONCLUSION In demographic and historical aspects old and young patients do not display major differences; however, the diagnosis is significantly delayed in the elderly. Early diagnosis with video EEG is recommended to avoid potential long-term risks associated with inappropriate treatments.

Angiogenesis in neurological disorders: a review.

Abstract Angiogenesis, recruitment of new blood vessels, is an essential component of the metastatic pathway. These vessels provide the principal route by which tumor cells exit the primary tumor site and enter the circulation. For many tumors, the vascular density can provide a prognostic indicator of metastatic potential, with the highly vascular primary tumors having a higher incidence of metastasis than poorly vascular tumors. The discovery and characterization of tumor-derived angiogenesis modulators greatly contributed to our understanding of how tumors regulate angiogenesis. However, although angiogenesis appears to be a rate-limiting event in tumor growth and metastatic dissemination, a direct connection between the induction of angiogenesis and the progression to tumor malignancy is less well understood. In this review, we discuss the observations concerning the modulation of angiogenesis and their implications in various neurological disorders, as well as their potential impact on cancer therapy.

The effects of brain stimulation of subthalamic nucleus surgery on gait and balance performance in Parkinson disease. A pilot study

Introduction Parkinsons disease (PD) is a progressive neurodegenerative disorder characterized by tremor, rigidity and bradykinesia. Gait and postural difficulties supersede tremor, rigidity and bradykinesia as drivers of disease burden in patients with advanced PD. The aim of this study was to describe the effects of deep brain stimulation of the subthalamic nucleus on gait ability and balance performance in patients with PD. Material and methods We studied 19 consecutive patients who underwent bilateral stimulation of the subthalamic nucleus. Patients were evaluated preoperatively and at the 5th day and 6th month after surgery. Timed Up and Go Test, 12 m Walking Test, Chair Stand Test and Berg Balance Scale (BBS) were used to assess mobility and balance performance. Unified Parkinsons Disease Rating Scale (UPDRS III) and Hoehn and Yahr Scale were also used. Results All the patients’ mobility ability and balance performance improved after surgery (p < 0.05). At the 6th month after surgery, the Timed Up and Go Test scores were decreased from 56.05 ±42.52 to 21.47 ±20.36, the 12 m Walking Test scores were decreased from 100.44 ±66.44 to 28.84 ±19.79, the Chair Stand Test scores were increased from 4.00 ±4.66 to 11.68 ±4.43 and the BBS score was increased from 12.84 ±6.89 to 38.89 ±8.79. UPDRS total scores were significantly improved 6 months after surgery (p < 0.001). UPDRS total scores were decreased from 98.26 ±37.69 to 39.36 ±18.85. The Hoehn and Yahr Scale score was significantly decreased after surgery (p < 0.05). Conclusions Surgical therapy is an effective treatment to improve gait ability and balance performance in Parkinsons patients.