Recep Demir

Toward Changing of the Pathophysiologic Basis of Acute Hydrocephalus After Subarachnoid Hemorrhage: A Preliminary Experimental Study

BACKGROUND Acute hydrocephalus (ventricular enlargement within 72 hours) is a common complication in patients with aneurysmal subarachnoid hemorrhage (SAH). Cerebrospinal fluid (CSF) secretion may be increased in the early phases of SAH, but it has not been proved definitively. We studied the histologic features of choroid plexus (CP) in the early and late phases of SAH. METHODS This study was conducted on 20 rabbits, with 5 rabbits in the control group, 5 rabbits in the sham group, and 10 rabbits in the SAH group. In the SAH group, five of the animals were decapitated after 2 days of cisternal blood injections, and the other five animals were decapitated after 14 days of injections. The CP of lateral ventricles were obtained from coronary sections of brains at the level of the temporal horns of the lateral ventricles. Sections were stained with hematoxylin and eosin and Masson trichrome for SAH-related damage and examined stereologically to discern water-filled vesicles, which were counted. Sections were compared statistically. RESULTS The mean numbers of water vesicles were different after SAH between the early decapitated group (group III) and the late decapitated group (group IV). The mean numbers of water vesicles were 2.80 (± 0.05) in the control group (group I), 2.76 (± 0.02) in the sham group (group II), 14.68 (± 0.06) in the early decapitated group (group III), and 4.78 (± 0.13) in the late decapitated group (group IV). Total number of fluid-filled vesicles of CP was also assessed stereologically; the total numbers were 840 (± 16) in group I, 828 (± 7) in group II, 4404 (± 19) in group III, and 1434 (± 41) in group IV. The numbers of water-filled cisterns were significantly increased in the early phases of SAH (P < 0.05). CONCLUSIONS In SAH with aneurysm rupture, increased CSF secretion seems to be triggered by hemorrhage in the early phase, but it is not possible in the late phase because of CP degeneration. In the early phase of hemorrhage, CSF secretion may be stimulated by the irritant receptor glossopharyngeal and vagal nerve endings, which innervate the healthy CP epithelium and arteries. Our findings may be accepted as being causative. It is likewise possible that CSF blockage per se leads to hydrocephalus, and the morphologic changes are sequelae that occur later in the course of disease. This is the first study to show the water vesicles of CP as a causative factor in the development of acute hydrocephalus after SAH.

Changes in the anti-oxidant system in adult epilepsy patients receiving anti-epileptic drugs

Abstract Anti-epileptic drugs (AEDs) have been widely used in patients with epilepsy. This study evaluated the adverse effects of two commonly prescribed AED monotherapies, carbamazepine (CBZ) and valproic acid (VPA). The aim of this study was to evaluate the influence of these anti-epileptic drugs on paraoxonase-1 (PON-1), glutathione S-transferase (GST) and acetyl cholinesterase (AChE) activities in the serum of adult patients with epilepsy. Of the 56 epileptic adults, 28 were given valproate, and the remaining 28 were given carbamazepine. Glutathione (GSH) levels in epilepsy patients receiving anti-epileptic drug treatment were insignificantly higher compared with controls. GST activity in epilepsy patients receiving anti-epileptic drug treatment was insignificantly lower compared with controls. PON1 and AChE activity in epilepsy patients receiving anti-epileptic drug treatment was significantly lower compared with controls. PON1 and AChE activities in the serum of patients treated with carbamazepine monotherapy were lower than in patients treated with valproic acid monotherapy.

Sensitivities of conventional and new electrophysiological techniques in carpal tunnel syndrome and their relationship to body mass index

The purpose of this study is to evaluate prospectively the sensitivities of conventional and new electrophysiological techniques and to investigate their relationship with the body mass index (BMI) in a population of patients suspected of having carpal tunnel syndrome (CTS). In this study, 165 hands of 92 consecutive patients (81 female, 11 male) with clinical diagnosis of CTS were compared to reference population of 60 hands of 30 healthy subjects (26 female and 4 male). Extensive sensory and motor nerve conduction studies (NCSs) were performed in the diagnosis of subtle CTS patients. Also, the patients were divided into subgroups and sensitivities were determined according to BMI. The mean BMI was found to be significantly higher in the CTS than in the control group (p < 0.001). The sensitivity of the median sensory nerve latency (mSDL) and median motor distal latency (mMDL) were 75.8% and 68.5%, respectively. The most sensitive parameters of sensory and motor NCSs were the difference between median and ulnar sensory distal latencies to the fourth digit [(D4M-D4U), (77%)] and the median motor terminal latency index [(mTLI), (70.3%)], while the median-to-ulnar sensory action potential amplitude ratio (27%) and the median-thenar to ulnar-hypothenar motor action potential amplitude ratio (15%) were least sensitive tests. Sensory tests were more sensitive than motor NCSs. Combining mSDL with D4M-D4U, and mMDL with mTLI allowed for the detection of abnormalities in 150 (91%) and 132 (80%) hands, respectively. Measurements of all NCSs parameters were abnormal in obese than in non-obese patients when compared to the BMI. The newer nerve conduction techniques and combining different NCSs tests are more sensitive than single conventional NCS test for the diagnosis of suspected CTS. Meanwhile, CTS is associated with increasing BMI.

Relationship of Asymmetrical Dimethylarginine, Nitric Oxide, and Sustained Attention during Attack in Patients with Major Depressive Disorder

We investigated the relationship of serum nitric oxide (NO) and asymmetrical dimethylarginine (ADMA) levels with cognitive functioning in patients with major depressive disorder (MDD). 41 MDD patients (Beck depression scale scores >16) and 44 controls were included in the study. Rey verbal learning and memory test, auditory consonant trigram test, digit span test, Wisconsin card sorting test, continuous performance task (TOVA), and Stroop test scores were found to be impaired in patients with major depressive disorder when compared to healthy controls. There was no significant difference between patient and control groups in terms of serum NO and ADMA. Serum NO levels were correlated with TOVA test error scores and Stroop test time scores, whereas serum ADMA levels were negatively correlated with TOVA test error scores. Metabolic detriments especially in relation to NO metabolism in frontal cortex and hypothalamus, psychomotor retardation, or loss of motivation may explain these deficits.

Red cell distribution width identifies cerebral venous sinus thrombosis in patients with headache.

Background: Diagnosing cerebral venous sinus thrombosis (CVST) in patients referring to emergency service or neurology outpatient unit with complaints of headache is a challenging task. Magnetic resonance (MR) venography is the gold standard, but there are limitations regarding its use. Aim: To evaluate the validity of red cell distribution width (RDW) in CVST diagnosis in patients presenting with headache. Methods: A total of 138 patients comprising 37 patients with CVST and 101 control primer headache cases were included in this retrospective cross-sectional study. Control group consists of hospitalized patients with primary headache. Venous blood hemoglobin (Hb), platelet, mean corpuscular volume (MCV), RDW, fibrinogen, and vitamin B12 levels of the patients were recorded at the first referral. Diagnosis of CVST was established by MR venography. Results: The RDW ratio of patients with a diagnosis of CVST was significantly higher than that in patients with primary headache (15.3 ± 1.4 vs 13.3 ± 0.5; P <.0001). Fibrinogen and vitamin B12 levels were not significantly different between the 2 groups. In a total of 11 patients, there was more than 1 thrombosis. In 21 of the patients with CVST, gene mutation was detected. There was no significant difference between the patients with and without mutations regarding RDW values. Diagnostic validity of RDW was found to be excellent in differentiating patients with CVST and primary headache (area under the curve = 0.996; 95% CI: 0.990-1.000). Optimum RDW cutoff value was determined as 14.1% (sensitivity: 91.9%, specificity: 99%, positive predictive value: 92.8, negative predictive value: 0.082). Conclusion: We suppose that among patients presenting with the complaint of headache, RDW value may lead to diagnose CVST.

PROGNOSTIC VALUES OF LESION VOLUME AND BIOCHEMICAL MARKERS IN ISCHEMIC AND HEMORRHAGIC STROKE: A STEREOLOGICAL AND CLINICAL STUDY

Purpose: Our aim was to evaluate the relationship between lesion volume, serum level of biochemical markers, and clinical situation in ischemic and hemorrhagic stroke. Methods: MRI was obtained on 33 ischemic and 28 hemorrhagic strokes. The Cavalieri method was used to measure the volume. To evaluate neurological situation of the patients, we used the National Institutes of Health Stroke Scale (NIHSS) and Rankin Disability Scores at the first, third, seventh, and thirtieth days. We measured the level of leptin, high sensitivity C-reactive protein (hs-CRP), insulin, cortisol, fibrinogen, protein C, protein S, von Willebrand factor, D-dimer, Antitrombin III, and Factor VIII (F VIII) at the same time intervals. Results: In ischemic events, cortisol level at third and seventh days, and fibrinogen level at the first day were correlated with lesion volumes (r = 0.5, p = .02; r = 0.4, p = .02; r = 0.5, p = .005, respectively). In hemorrhagic events, only fibrinogen level was correlated with lesion volumes at third day (r = 0.6, p = .04). No significant differences were found among all these biochemical parameters, neurological situation (p > .05), and lesion volumes at all times. Conclusion: In the prediction of stroke prognosis, lesion volume and all of the evaluated biochemical parameters are not deterministic factors.

Investigation of the effect of telmisartan on experimentally induced peripheral nerve injury in rats

Aim: The aim of this study was to investigate the effects of telmisartan on nerve healing in a rat peripheral nerve injury model. Material and method: Thirty adult male Wistar albino rats were divided into five groups: healthy, axonotmesis, anastomosis, axonotmesis+10 mg/kg telmisartan and anastomosis+10 mg/kg telmisartan. Walking track analyses were performed 4 weeks after the surgery. The right sciatic nerves of all the animals were examined histopathologically, stereologically and molecularly. Results: Many badly damaged axons were detected in the axonotmesis group, in addition to enlarged spaces between the axons. In the anastomosis group, both ir-regular and degenerated axons at different severities were observed. The sections of the telmisartan group after the axonotmesis were similar to those of the healthy group. The sections of the telmisartan group after the anastomosis were similar to those of the healthy group and the telmisartan group after the axonotmesis. Interleukin-1 beta (IL-1β) gene expression increased in both the axonotmesis and the anastomosis groups when compared with the healthy group. Telmisartan had a significant down-regulatory effect on IL-1β expression. Caspase-3 mRNA expression was significantly increased in the anastomosis group, and the administration of telmisartan in this group significantly decreased this rise in caspase-3 mRNA expression. As a functional outcome, telmisartan also increased the walking distance of the rats after axonotmesis and anastomosis. Conclusion: The histopathological, stereological, functional and molecular data suggest that telmisartan improves nerve regeneration in peripheral nerve injuries by inhibiting inflammatory cytokine IL-1β and apoptotic caspase-3.

Does bosentan protect diabetic brain alterations in rats? The role of endothelin-1 in the diabetic brain.

Diabetes mellitus (DM) is a major problem all over the world, affecting more people in recent years. Individuals with diabetes are more prone to disease than non‐diabetics, especially vascular complications. The aim of this study was to examine the roles of the endothelin (ET)‐1 in brain damage formed in a streptozocin (STZ)‐induced diabetes model, and the effect of bosentan, which is the non‐specific ET1 receptor blocker in the prevention of the diabetes‐induced brain damage. To examine the effects of bosentan (50 mg/kg and 100 mg/kg) in this study, the rats were given the drug for 3 months. The rats were divided into four groups: the sham group (n = 10), the diabetic control group (n = 10), the group of diabetic rats given bosentan 50 mg/kg (n = 10) and the group of diabetic rats given bosentan 100 mg/kg (n = 10). Diabetes was induced in the rats by STZ (60 mg/kg i.p.). On day 91, all rats were killed. Brain tissues of the rats were measured by molecular, biochemical and histopathological methods. Antioxidant levels in the therapy groups were observed as quite near to the values in the healthy group. In this study, while the brain eNOS levels in the diabetic groups decreased, the ET1 and iNOS levels were found to be increased. However, in the diabetes group, hippocampus and cerebellum, pericellular oedema and a number of neuronal cytoretraction were increased in neuropiles, whereas these results were decreased in the therapy group. Based on all of these results, ET1 will not be ignored in diabetes‐induced cerebral complications.

Protective effects of alpha-lipoic acid on experimental sciatic nerve crush injury in rats: assessed with functional, molecular and electromicroscopic analyses

Aim: The present study aimed to demonstrate protective effects of alpha lipoic acid on experimental sciatic nerve crush injury model assessed with functional and electronmicroscopy analyses. Methods: In this study, groups were; Group 1; sham operated, Group 2; applied only sciatic nerve crush (Control), Group 3; Sciatic nerve crush + treated ALA 25 mg/kg (received orally) and Group 4; Sciatic nerve crush + treated ALA 50 mg/kg. Subsequently, sciatic nerves crush injury induced by forceps. At the second and fourth week, all animals were evaluated for sciatic functional index (SFI) and histomorphometric analyses with electronmicroscopy. Results: The SFI was significantly increased for both ALA-treated groups 30 days post-injury compared with control groups. The elecronmicroscopy results demonstrated that the axon diameter, the myelin diameter, the area of regenerating axon and miyelin were better in the treatment group than in the control group. Also ALA decreased IL-1β and Caspase 3 levels that increased in SNC group. Conclusions: These results suggest that ALA neuroprotective agent for peripheral nerve injury (PNI) and promoted peripheral nerve regeneration via its anti-inflammatory and antiapoptotic effects.

Karpal tünel sendromunda Novel metoduyla yapılan steroid enjeksiyonunun ağrı şiddeti ve elektrofizyolojik bulgular üzerine etkisi

Objective: The aim of the present study is to investigate the effects of local steroid injection therapy with the Novel method on subjective patient complaints and electrophysiological investigations at the end of 3 months. Methods: 101 hands of 59 subjects (5 men and 54 women) with mild carpal tunnel syndrome received steroid injection with the Novel technique. Visual Analogue Scale (VAS) was used to determine the severity of pain. Nerve conduction findings obtained prior to and 3 months after the injection were compared using the VAS. Results: According to the VAS, mean pain severity for the right hand (n:56) was 7.79±1.4 before the injection, and 3.29±1.9 at 3 months. Mean pain severity for the left hand (n=45) was 7.71±1.2 before the injection, and 3.16±2.0 at 3 months. Median motor nerve distal latency was statistically significant for both hands after the injec tion (p<0.001). Median motor velocity was statistically non-significant in both hands after the injection. After the injection, median sensory distal latency, amplitude and velocity were statistically significant for both hands. Conclusion: The present study showed the efficacy of local steroid injection therapy on subjective complaints and electrophysiological findings in mild carpal tunnel syndrome. Because the improvement is greater in the non-dominant hand compared to the other, splints should be used to keep the hand in neutral position and hand rest should be employed in addition to the local injection.