Effects of the Experiment Conditions on the Nerve Action Potential: A Model Study

Like electrical wires, neurons were recognized to convey information from one part of the body to another in the form of electricity. Due to its electrical nature, this transmission is very much dependent on the ions around their membranes. As in the case of all electrical messages of the nervous system, the action potential is a membrane potential change caused by the flow of ions through ionic channels in the membrane. With the help of the action potential simulation we test the effect of extracellular ion concentrations on the myelinated single nerve fiber action potential. Tests were designed to mimic the hypo/hyperkalemic and hypo/hypernatremic conditions. Our simulation results have shown that sodium ion channel conductivity is much more susceptible to the changes in the extracellular ion concentrations. Due to more susceptible nature of the sodium channel conductivity –with respect to potassium-, hypo/hyperkalemic conditions are much more dangerous for patients at least for neuronal conduction

The Cervical Epidural Space Metastasis of Ewing's Sarcoma

Ewing's sarcoma is a primary bone malignancy with the highest incidence in the first to third decades of life. That in both locations follow a rapid course with metastasis to lung and bone. Ewing's sarcoma of the spine is a rare condition that appears with a clinical triad of local pain, neurological deficit and a palpable mass. The definitive management of Ewing's sarcoma of the spine, as in other locations, could include three main modalities: surgery, radiotherapy, and chemotherapy. In the presence of acute neurological decompensation, decompressive surgery via an appropriate approach should be performed. In this study; a 32-year-old male with a sudden progressive severe upper extremity spastic paresis and paraplegy has been presented. We wanted to discuss the preoperative process and treatment modalities

Currarino syndrome: report of five consecutive patients

WOS: 000332319200024PubMed ID: 24013264The Currarino syndrome is regarded as a developmental disorder based on its recognized etiological heterogeneity. This syndrome is thought to result from abnormal separation of the neuroectoderm from the endoderm. Our aim was to report the neurosurgical management of Currarino syndrome in children and adults and to describe what clinician could do if the Currarino triad was suspected. We present five cases of Currarino triad who underwent surgical intervention. All patients had sacral bony deformity, anorectal malformations, and anterior sacral meningocele. A 40-year-old-male had chronic constipation. He was incidentally diagnosed with Currarino syndrome. A 19-year-old-female suffered from a slight weakness in lower extremities and urinary incontinence. Her past medical history was remarkable for anal atresia. The other three cases were children. When an anterior sacral meningocele is encountered, Currarino syndrome should be taken into consideration. Although it is rarity, the Currarino syndrome might be one of the causes of chronic constipation. Endoscopic or endoscope-assisted surgery via a posterior sacral route can be feasible for treatment of some of the patients with anterior sacral meningocele. Anterior meningocele pouch associated with Currarino syndrome will regresses over time following transdural ligation of its neck

Clinical Features, Treatment and Outcome of Childhood Glial Tumors.

AIM: To evaluate the clinical features, treatment approaches, and outcomes of glial tumors in children. MATERIAL and METHODS: Files (2006 to 2020) of children diagnosed with glial tumors and followed-up were reviewed retrospectively. Information regarding demographic and clinical characteristics, treatment approaches, and outcomes were retrieved from the patients' files. RESULTS: Of the total of 180 pediatric patients diagnosed with brain tumors, 73 (40.6%) had glial tumors. The children with astrocytoma were in the age range of 2-18 years (median age: 8.7 years), while the ages of children with ependymoma ranged from three months to 10 years (median age: 3 years). This difference was statistically significant (p<0.0001). The male to female ratio was 1.6. The most common symptoms or signs were headaches (n=34, 46.6%), abnormal gait or coordination (n=22, 30.2%), vomiting (n=21, 28.8%), and cranial nerve palsies (n=20, 27.4%). The pathological diagnoses were astrocytomas (n=53, 72.6%), oligodendroglial tumors (n=2, 2.7%), ependymoma (n=15, 20.7%), and other glial tumors (n=3, 4.1%). The most common tumor location was supratentorial (n=42, 57.5%), while midline glioma was detected in seven patients. The 5-year overall survival (OS) rate of all glial tumors, astrocytoma, and ependymoma was 42%, 40%, and 55%, respectively. The 5-year OS rate of the tumor Grade I, II, III, and IV was 77.2%, 45%, 32%, and 0%, respectively (p<0.0001). The 5-year OS rate of supratentorial, infratentorial, and spinal tumors was 25.6%, 63.6%, and 50%, respectively (p=0.021). In Cox regression analysis, it was found that the tumor resection and grade had an effect on the tumor prognosis. CONCLUSION: Treatment results are not satisfactory in high-grade astrocytomas. There is a need for new treatment approaches that would take cognizance of molecular features and adopt multidisciplinary approaches

Controlled Trial of Efficacy of Dexketoprofen in Sciatic Nerve Crush Injury in Rats

WOS: 000343369500014Object: Local applications of Dexketoprofen trometamol (dex) have been shown to increase in the sciatic nerve functional tests following the nerve injuries. The aim of the current study was to compare the efficacy of dex application for 1 and 5 days following nerve injury rat model. Possible effects of dex were checked by means of the Sciatic Function Index (SFI), Withdrawal of the Reflex Leg (WRL), number of axons, axon diameter, and nerve diameters. Material Methods: The animal crushed model was done through Aesculap -Yasargil aneurysm method on Wistar albino (N=21) right sciatic nerves. In order to achieve desired purpose 3 experimental groups were organized: Group 1: control (injured and no drug); Group2: dexketoprofen 1 days (injured and single dose of drug); Group3: dexketoprofen 5 days (injured and single dose of 5 times drug applications). Injections were done through the tissue expander's injection port with a connecting tube directed at the crush-injured site. Functional recovery of the sciatic nerves was evaluated with the improvement in the SFI values. Additionally, recovery of sensory function was assessed through WRL results and histopathological examination was performed 6 week following the injury. Results: At the end of the experimental periods there was no significant differences were found between the experimental group of animals on the bases of the number of axons, axon diameter, and nerve diameter. Moreover, up 30th day of the experimental period our functional test results have shown that there was no difference between the groups. But following the induction of the injury, the statistical significances were seen on the functional tests. This effect was seen only if the multi-dose application of the dex. Conclusions: This study suggests that; dexketoprofen trometamol of 5 consecutive days, has revealed positive significant changes in the sciatic nerve injury through analgesic effect of it

Protective Effects of Methotrexate and Tenoxicam in Peridural Fibrosis in Rat Laminectomy Model

WOS: 000365428100007Objective: Peridural fibrosis after laminectomy is an important surgical problem. Tenoxicam is a nonsteroidal antiinflammatory drug and an oxicam derivative acting by inhibiting the formation of prostaglandin and eicosanoids. Low dose methotrexate which has been used as an antiinflammatory agent rhomatoid arthritis inhibits the synthesis of potentially toxic compounds those accumulate in inflamed tissues. The aim of this study was to evaluate and compare the efficacy of these two independent pharmacological agents in the inhibition of peridural fibrosis. Methods: L3-4-5 bilateral laminectomy with sparing the dura mater integrity was perfomed to 30 male Wistar albino rats. Except the SHAM group, low dose methotraxate (0.2 mg/kg) or tenoxicam (0.5 mg/kg) was administered on the dura mater before the surgical closure. After 42 days, all rats were euthanized and their spinal columns performed laminectomy were removed for the histopathological evaluation. Results: The peridural fibrosis grades of the groups administered low dose methotrexate or tenoxicam were lower than SHAM group grades. They have lower fibroblast counts than SHAM group numerically, although there was no statistically significant difference among groups. Conclusion: Local usage of low dose methotrexate and tenoxicam may be helpful option for prevention of peridural fibrosis after laminectomy procedures in future

Congenital supratentorial cystic hemangioblastoma

PubMed ID: 18154025Supratentorial hemangioblastomas are rarely encountered tumors even in the pediatric population; an extensive review of the literature has revealed approximately 118 cases. However, only five of these occurred in infants, and three occurred during the first 2 months of life. A 5-week-old boy presented with emesis, irritability, a bulging anterior fontanelle, and a head circumference that had gradually expanded since birth. His medical and family histories were uninformative in terms of cancer or inherited diseases. Magnetic resonance imaging demonstrated a large loculated cyst with a heterogeneous contrast-enhancing 3-cm nodule, first pushing the left frontal and parietal lobes and then displacing into this region. After being exposed via a left frontoparietal craniotomy, the cyst was evacuated by a soft drain, and then the mass was totally excised. The histopathological diagnosis was a reticular variant of hemangioblastoma. Given that von Hippel-Lindau (VHL) gene mutations may be associated with hemangioblastomas, sequencing analysis of the VHL gene was performed; sequencing of the three exons of the VHL gene showed no exonic mutations. Clinical and neuroimaging follow-up of the patient have revealed an improved health status during the last 23 months. The authors reviewed the literature concerning congenital supratentorial hemangioblastomas, and they discuss the clinical and histopathological characteristics and differential diagnosis associated with such lesions