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Biomedical subjects

Cemal Ozcan

Publications and source records attributed to Cemal Ozcan.

16 recordsLinked to original sources

Reduced P50 auditory sensory gating response in professional musicians.

Evoked potential studies have demonstrated that musicians have the ability to distinguish musical sounds preattentively and automatically at the temporal, spectral, and spatial levels in more detail. It is however not known whether there is a difference in the early processes of auditory data processing of musicians. The most emphasized and studied early process, especially for neuropsychiatric purposes, is sensory gating. The suppression percentage of the midlatency auditory evoked potential P50, and rarely the N100, wave is used for sensory gating studies. Our aim in this study was to investigate whether there was a difference in the auditory P50 and N100 suppression of control subjects who were professional musicians with no psychiatric problems. 34 professional musicians and 19 non-musicians (the control group) were included in this study. P50 and N100 measurements were taken, the suppression percentage of P50 and N100 was calculated and the results compared. Musicians showed significantly less P50 suppression when compared to non-musicians. There was no significant difference for N100 suppression. What the decreased P50 suppression in musicians when compared to non-musician subjects means, when we also take into account that N100 suppression is not decreased, and how it may contribute to the music perception and production processes of these persons is discussed.

Adult↗

Caffeic acid phenethyl ester (CAPE) attenuates cerebral vasospasm after experimental subarachnoidal haemorrhage by increasing brain nitric oxide levels.

BACKGROUND: Cerebral vasospasm, a medical complication of aneurysmal subarachnoid hemorrhage (SAH), is associated with high morbidity and mortality rates, even after the aneurysm has been secured surgically or endovascularly. Evidence accumulated during the last decade suggest that scavenging a vasodilator, nitric oxide (NO), by superoxide anions (O(2)(-)), and activating a strong vasoconstructor, protein kinase C (PKC), are the two most important mechanisms in the pathogenesis of vasospasm. Our aim in this study was to determine whether caffeic acid phenethyl ester (CAPE), a non-toxic oxygen free radical scavenger, prevents vasospasm in an experimental rat model of SAH. METHODS: Twenty eight rats (225-250 g) were divided into four groups equally: group 1, control group; group 2, SAH group; group 3, SAH plus placebo group; and group 4, SAH plus CAPE group. We used double haemorrhage method for SAH groups. Starting 6h after SAH, 10 micromol/kg CAPE or an equal volume of 0.9% saline were administered by intraperitoneal injection twice daily for 5 days to SAH plus CAPE and SAH plus placebo groups, respectively. CAPE or 0.9% saline injections were continued up to 5th day after SAH. Rats were sacrificed on the 5th day. Brain sections at the level of the pons were examined by light microscopy. Measurements were made for the cross-sectional areas of the lumen and the vessel wall (intimae plus media) of basilar artery by a micrometer. The levels of malondialdehyde (MDA), reduced glutathione (GSH), and nitric oxide (NO) were measured in rat brain tissue. RESULTS: Administration of CAPE significantly attenuated the vasoconstriction of the basilar artery. There were marked narrowing in the lumens of and thickening in the walls of basilar arteries in the SAH, and the SAH plus placebo compared with CAPE group (p < 0.001). We also observed that CAPE administration significantly decreased the tissue level of MDA, while significantly increased the tissue levels of GSH, NO in the SAH plus CAPE group compared to only SAH group, p < 0.05. CONCLUSIONS: Our results indicate that CAPE is effective in attenuating delayed cerebral vasoconstriction following experimental SAH. Our findings also suggest that the elevation of lipid peroxidation and reduction of NO bioavailability, resulting from the generation and the interaction of free radicals, have a significant role in the pathogenesis of vasospasm after SAH.

Animals↗

Sympathetic skin responses in Type-1 diabetic children: relationship to urodynamic findings.

AIMS: Cystopathy is an important problem in diabetes mellitus (DM) when diabetes is not well-controlled. In most cases of diabetic csytopathy, autonomic involvement is responsible, which develops insidiously over a long time. We investigated the hand and genital sympathetic skin responses (SSRs) and its relation to urodynamic abnormalities in this group of patients. METHODS: We performed hand and genital SSRs in 24 children with Type-1 DM, whose hemoglobin A1C values were above normal limits. We also recruited 19 healthy children for SSRs measurements. Cystometry was performed in 24 children with Type-1 DM. Based on cystometry findings, these children were classified into two groups as normal (n:6) and abnormal (n:18). The amplitude and latency of hand and genital SSRs of 24 children with Type-1 DM and 19 healthy children were compared. RESULTS: Hand and genital SSRs were obtained from all of the diabetic and healthy children. The mean genital SSRs amplitude in diabetic children was significantly lower than the controls. There was no difference in the mean values of all investigated parameters between the normal group and controls. When compared to the controls, there was prolonged latency and decreased amplitude of genital SSRs and decreased hand SSRs amplitude in abnormal group. CONCLUSIONS: SSR is a non-invasive test for the evaluation of autonomic sympathetic involvement. Our study revealed differences in genital SSR before the manifestations of cystopathy. Children with abnormal urodynamic findings had changes in both hand and genital SSRs. These findings suggest that SSR tests may have a place in the evaluation of diabetic cystopathy in the early asymptomatic period.

Adolescent↗

Decreased endothelium-dependent vasodilatation in patients with migraine: a new aspect to vascular pathophysiology of migraine.

BACKGROUND: Migraine is a common neurovascular disorder characterized by attacks of severe headache, autonomic and neurological symptoms. We hypothesized that patients with migraine had abnormal endothelial function. The vascular theory of migraine assumes that the major pathophysiological events that initiate the migraine attack occur in the perivascular nerves of the major cerebral vessels. Accordingly, we aimed to measure endothelium-dependent vasodilatation in migraineurs by means of flow-mediated dilatation, which reflects endothelium-dependent vasodilatation capacity. MATERIALS AND METHODS: Forty-five patients who fulfilled the diagnostic criteria for migraine and 45 age and sex-matched healthy participants were enrolled in the study. Flow-mediated dilatation of the brachial artery was determined using a high-resolution B-mode ultrasonographic system. Flow-mediated vasodilatation was expressed as the change in post-stimulus diameter as a percentage of the baseline diameter. RESULTS: Mean ages of the patients were 33+/-10 years in migraineurs (range: 18-52 years, 36 female, 9 male) and 33+/-9 years in non-migraineurs (range: 17-50 years, 36 female and 9 male). Flow-mediated dilatation of patients with migraine is significantly lower than that of the controls (8.02+/-4.095% vs. 10.72+/-3.52%, respectively, P=0.001). CONCLUSION: We have shown that migraineurs have decreased endothelium-dependent vasodilatation capacity compared with non-migraineurs. Migraine may be a local manifestation of systemic vascular vasomotion abnormalities.

Adolescent↗

Sympathetic skin response in premenstrual syndrome.

Premenstrual syndrome is a term which includes a broad group of emotional, behavioral and physical symptoms that occur for several days before menses and subside following the menstrual period. Many women experience premenstrual syndrome symptoms, particularly physical ones such as breast tenderness and swelling. Approximately 5-10% women suffer from severe premenstrual syndrome and another 30-40% have moderate symptoms. Premenstrual syndrome continues to be an unsolved problem. In this study, we evaluated 24 premenstrual syndrome patients and 20 healthy women in the control group. The ages of the women were 22-34 years (mean +/- SD: 25+/-3) for the premenstrual syndrome group and 23-34 (25+/-3) for the control group. The sympathetic skin response was recorded from the palms, soles and genital regions by using electrical stimuli to the median nerve at the wrist. The sympathetic skin response was recorded twice, in the follicular and late luteal phases of menstruation. The follicular and late luteal phase sympathetic skin response of the two groups were compared. The amplitudes and latency values of the late luteal and follicular phase sympathetic skin response from the premenstrual syndrome group and control group women were statistically similar. We also did not find any latency or amplitude difference in the sympathetic skin response obtained from the three regions of the premenstrual syndrome patients and the control group. We checked sympathetic skin response in the symptomatic (late luteal phase) and asymptomatic (follicular phase) periods of patients with premenstrual syndrome, a disorder known to have many autonomic symptoms, to determine whether there was sudomotor sympathetic involvement. The results of our PMS patients indicate at the very least that there is no difference with the control subjects as regards peripheral sudomotor functions.

Adult↗

Cerebral artery hemodynamics in polycystic ovary syndrome.

OBJECTIVE: The aim of the present study was to investigate hemodynamic changes in the medial cerebral artery and also the internal carotid artery in young women with polycystic ovary syndrome (PCOS) and polycystic ovaries (PCO). METHODS: Twenty-eight patients with PCOS, 16 patients with PCO and 24 healthy control subjects were included in the study. Blood flow rate, pulsatility index and back pressure of both the medial cerebral artery and the internal carotid artery were determined by transcranial Doppler ultrasonography and the results compared between groups. RESULTS: There were no significant differences between the groups in bilateral medial cerebral artery and internal carotid artery blood flow rate, pulsatility index and back pressure. CONCLUSION: Our results do not indicate whether the risk of cerebrovascular events will increase for PCOS patients in middle and advanced age, but do show that changes in cerebral hemodynamics are not likely in PCOS at an early stage.

Adolescent↗

Cognitive event-related potential and neuropsychological findings in Behcet's disease without neurological manifestations.

Behcet's disease (BD) is a multisystem inflammatory disorder characterized by recurrent oral and genital ulcers and uveitis. BD patients without neurological involvement frequently have mild neurological symptoms. The aim of this study was to evaluate whether BD patients without neurological involvement have any changes in cognitive functions. Twenty BD patients without neurological involvement and 13 control subjects were included in the study and were analyzed by neurophysiological and neuropsychological examinations. The cognitive event-related potentials (P300) were recorded from the frontal, central and parietal areas of the right and left hemispheres of the patients and control subjects. Likewise, all individuals were evaluated with neuropsychological tests. In contrast to a study with similar design, we did not find any difference between the cognitive event-related potentials values of BD patients without neurological involvement and the control subjects. All BD patients without neurological involvement exhibit normal results of the neuropsychological test. In conclusion, the results of neuropsychological tests and cognitive event-related potentials values in BD patients without neurological involvement are indistinguishable from those in control subjects and no alteration of cognitive functions is present.

Adolescent↗

Topographic abnormalities in event-related potentials in children with monosymptomatic nocturnal enuresis.

AIMS: A functional maturational delay in the central nervous system is dwelled upon in the pathogenesis of monosymptomatic nocturnal enuresis (MNE). In this study we studied whether according to controls N200 and P300, components of the event-related potential (ERP), which is related to aspects of cognitive processing, showed any difference in its topographic distribution in children within the age group 10-13 with monosymptomatic nocturnal enuresis and discussed its relation to the pathogenesis of MNE. METHODS: We performed P300 in 18 patients with MNE and in 16 age-matched healthy subjects. P300 were evoked by an auditory oddball paradigm consisting of 150 tone bursts (80% 1 kHz; 20% 2 kHz). The latencies of the N200 and the P300 waves and the amplitude of the P300 wave were measured. RESULTS: There was no statistical difference between the enuretic group and the controls in N200 and P300 latency and amplitude in the midline frontal (Fz), central (Cz), and parietal (Pz) recording site of the 10-20 International System. In the enuretic group while P300 amplitude in the Fz site was significantly less than the P300 amplitude in the Cz site, there was no statistical difference between the Fz and Pz P300 amplitude values. CONCLUSIONS: When different levels of maturational delay are considered in MNE, it may be claimed that maturational delay in children whose enuresis lasts until older ages will be different from those whose enuresis ends at an early age. The determination of P300 amplitude in parietal records being less in enuretics when compared to the controls may show that there are regional differences in stimuli processing rate/quality.

Acoustic Stimulation↗

Isolated intracranial hypertension: a rare presentation of neurobrucellosis.

Brucella melitensis infection is endemic in the eastern and south-eastern Anatolia regions of Turkey. We report an unusual case of brucella meningitis presenting with bilateral papilla stasis, diplopia and absence of other neurological involvement. Diagnosis was made by positive culture of Brucella spp. with a BACTEC 9120 system with inoculation of the patient's cerebrospinal fluid (CSF). This is the first report of isolation of Brucella spp. from CSF on a BACTEC 9120 system for diagnosis of meningitis. This case demonstrated that brucella meningitis may present with very slight symptoms, and inoculation of CSF into BACTEC bottle besides conventional cultures improves the detection of Brucella in endemic areas such as Turkey.

Adult↗

Occupational prolonged organic solvent exposure in shoemakers: brain MR spectroscopy findings.

Our purpose was to investigate, by magnetic resonance (MR) spectroscopy, the metabolite changes in the brains of subjects in the shoemaking industry who had been chronically exposed to organic solvents. A total of 49 male subjects and 30 age-matched healthy volunteers underwent detailed neurological and psychiatric examinations. All subjects had long-echo [repetition time (TR) 2000 ms, echo time (TE) 136 ms] single-voxel MR spectroscopy. Voxels (15 x 15 x 15 mm(3)) were placed in the parietal white matter, thalamus, and basal ganglia. N-acetylaspartate (NAA)/creatine (Cr) and choline (Cho)/Cr ratios were calculated. There was no significant difference between the study subjects and the control group in NAA/Cr ratios obtained from thalamus, basal ganglia, and parietal white matter. Cho/Cr ratios in thalamus, basal ganglia, and parietal white matter were found to be significantly increased compared to controls. There was a positive correlation between basal ganglia Cho/Cr ratio and duration of exposure (r = 0.63). MR spectroscopy should be performed to reveal metabolite changes and determine the degree of brain involvement in solvent-related industry workers.

Adolescent↗

Clitoral electromyography.

PURPOSE: The clitoris has several histomorphological and functional similarities to the penis. In this study we evaluated spontaneous and evoked electromyography activity in the clitoris. MATERIALS AND METHODS: We evaluated 11 healthy female volunteers with clitoral electromyography using a concentric needle electrode placed intracorporeally. The hand, foot and genital sympathetic skin responses, and spontaneous electrodermal activity were simultaneously recorded with silver surface electrodes. Another concentric needle electrode was placed subdermally on the mons pubis to differentiate clitoral activity from possible artifact. After recording spontaneous electromyography and electrodermal activity the left median nerve was stimulated to record evoked clitoral activity, and the sympathetic skin response in the hand, foot and genital regions. RESULTS: There was spontaneous electromyography activity in the corpus clitoris. All dermal sites, including the hand, foot and genital regions, showed spontaneous electrodermal activity. No spontaneous activity was recorded from the subdermal needle electrode. Distraction of attention and coughing increased the amplitude and frequency of spontaneous clitoral electromyography and electrodermal activity at all sites. After stimulating the left median nerve all sites except that of the subdermal needle electrode showed evoked activity. CONCLUSIONS: The demonstrated evoked and spontaneous clitoral electromyography activity seems to indicate a sympathetic tonus of the corpus clitoris, as recorded from the corpus cavernosum of the penis in human males. Clitoral electromyography may be a useful objective assessment tool for evaluating female sexual dysfunction as well as genital autonomic innervation.

Adult↗

Evoked cavernous activity.

PURPOSE: Corpus cavernosum electromyography has been widely done to evaluate autonomic dysfunction in patients with erectile dysfunction. We assessed the value of corpus cavernosum electromyography, evoked cavernous activity and penile sympathetic skin responses for their accuracy in determining autonomic involvement in cases of erectile dysfunction. MATERIALS AND METHOD: We evaluated 75 men with erectile dysfunction by corpus cavernosum electromyography, evoked cavernous activity and penile sympathetic skin response tests at our neurourology laboratory. The etiology of dysfunction was vascular, neurogenic, psychogenic or mixed based on a detailed medical and sexual history, physical examination, electrophysiological and laboratory studies, penile color Doppler ultrasonography, and cavernosography and/or cavernosometry. Autonomic involvement was clinically assessed by systemic findings, such as orthostatic hypotension, impaired gastrointestinal motility, sinus dysrhythmia and secretomotor changes. A concentric electromyography needle placed in the right cavernous body was used to record corpus cavernosum electromyography and evoked cavernous activity. The right median nerve was stimulated electrically with 13 to 16 mA. to determine evoked cavernous activity and the penile sympathetic skin response. The latter response was recorded with silver disc electrodes placed on the left cavernous body. All tests were performed using an electromyography/evoked potential machine. We determined the relationships among corpus cavernosum electromyography, evoked cavernous activity and penile sympathetic skin response tests in respect to etiological factors. RESULTS: The 56 patients with normal corpus cavernosum electromyography activity had also evoked cavernous activity and a penile sympathetic skin response except for 1 with no penile sympathetic skin response but evoked cavernous activity. None of these patients had autonomic neuropathy. Of the 19 patients without corpus cavernosum electromyography activity 11 had evoked cavernous activity, including 10 with no autonomic neuropathy. The remaining 8 patients had no evoked cavernous activity, of whom 7 had autonomic neuropathy. A penile sympathetic skin response was recorded in 18 men with absent corpus cavernosum electromyography. CONCLUSIONS: Due to false-negative results on corpus cavernosum electromyography and penile sympathetic skin response testing evoked cavernous activity seems more reliable for determining autonomic involvement in the pathophysiology of erectile dysfunction.

Adult↗

Cervical hematomyelia: a rare entity in a neonate with cesarean section and surgical recovery.

Spinal cord injury with or without trauma has been reported in the perinatal period. The prognosis depends primarily on diagnosis of the level, extent and nature of the lesion, established by correlations between clinical, imaging and electrophysiological data. A 25-day-old boy with normal birth weight delivered at term by cesarean section was transferred to Inönü University Turgut Ozal Medical Center because of respiratory distress and brachial diplegia. A suspicious medullary lesion on cervical computerized tomography was confirmed as an intramedullary lesion extending from C3 to D1 on magnetic resonance imaging (MRI). Emergent surgery consisting of exposure of the lesion site and interlaminar direct puncture of the lesion under fluoroscopy revealed that the pathology was an intramedullary hematoma. The partial evacuation of the lesion with direct puncture, the patient's neurological improvement and close follow-up of the patient with ultrasonography, electrophysiology and MRI are discussed in the light of recent literature.

Birth Injuries↗

The role of oxidative stress in postoperative delirium.

AIM: This study aimed to determine a marker that predicts delirium using preoperative oxidative processes in patients undergoing cardiopulmonary bypass surgery. METHOD: Twelve of the 50 patients included in the study showed signs of delirium during postoperative follow-up. The Delirium Rating Scale was used in patients with delirium according to DSM-IV-TR in the postoperative period. Venous blood samples were obtained from the patients the day before and the day after the surgery to determine plasma antioxidant enzyme levels. RESULTS: While there were no differences in preoperative superoxide dismutase (SOD), glutathione peroxidase (GSH-Px) and malondialdehyde (MDA) levels in both groups, catalase (CAT) levels were significantly lower in the delirium group. Postoperative SOD and MDA levels were also higher in the delirium group, while the GSH-Px levels were found to be lower when compared with those during the preoperative period. In the nondelirium group, the postoperative MDA and GSH-Px levels were found to be lower than preoperative levels, and postoperative SOD levels were found to be higher than preoperative levels. CAT levels were lower in the delirium group when the pre- and postoperative levels were compared in both groups. The postoperative levels of SOD, GSH-Px and CAT in the nondelirium group and MDA in the delirium group were significantly higher than preoperative levels. CONCLUSION: Patients with low preoperative CAT levels appeared to be more susceptible to delirium than patients with higher CAT levels.

Aged↗

Crocodile tears syndrome: botulinum toxin treatment under EMG guidance.

Crocodile tears syndrome is one of the rare complications of facial paralysis. There have been several reports of cases in which botulinum toxin was found to be useful in the treatment of crocodile tears syndrome. The adverse effects, due to the paralytic action of botulinum toxin, have been reported to involve the palpebral muscle, lateral rectus and superior rectus. Therefore, we considered that it might be more appropriate to carry out the injection procedure under electromyographic guidance in order to inject botulinum toxin selectively into the lacrimal gland and protect the above-mentioned muscles. In conclusion, we recommend EMG guidance in the treatment of crocodile tears syndrome with botulinum toxin.

Adult↗