High-density lipoprotein dysfunction in carotid artery stenosis.

Background: High density lipoprotein (HDL) is well established to have an athero-protective role under normal conditions; however, pro-inflammatory alteration of HDL proteins may transform the HDL particle into a dysfunctional molecule. Our aim was to investigate HDL dysfunction by measuring enzyme-based markers in carotid artery stenosis (CAS). Patients and methods: All participants underwent duplex ultrasound and 52 subjects diagnosed with CAS and 51 subjects who had no significant stenosis (as controls) were enrolled in this study. Serum lipid profiles and serum parameters associated with dysfunctional HDL including myeloperoxidase (MPO), paraoxonase 1 (PON1), arylesterase (ARE) activity, and lipid hydroperoxide (LOOH) levels were measured. Results: It was found that the patients with CAS had increased levels of MPO and LOOH while PON1 activity was decreased. There was no significant difference between the CAS and non-CAS groups in terms of HDL levels. MPO/PON1, MPO/ARE, and LOOH/PON1 ratios were significantly increased in the CAS group. MPO/PON1 and MPO/ARE ratios both demonstrated significant correlations with degree of stenosis (%). Conclusions: The MPO/PON1 and MPO/ARE ratios may be potential serum markers that can enable the monitoring of HDL functionality and the assessment of atherosclerotic disease risks. Additionally, monitoring the oxidative balance of lipids on HDL molecules by LOOH/PON1 ratio may have value in the early detection of pro-atherosclerotic transformation of the HDL particle.

The Relationship between Visual-Evoked Potential and Optic Coherence Tomography and Clinical Findings in Parkinson Patients.

Background: In Parkinson's disease (PD), dopamine deficiency is present not only in the nigrostriatal pathway but also in the retinal and visual pathways. Optic coherence tomography (OCT) can be used as morphological evidence of visual influence from early nonmotor symptoms. The aim of this study was to investigate the relationship of OCT and visual evoked potentials (VEPs) of eyes with the severity of clinical findings and ocular findings in PD. Methods: A group of 42 patients diagnosed with idiopathic PD and a control group of 29 people between the ages of 45-85 were included in our study. VEP was recorded in the patient and control groups. OCT measurement was made with the Optovue spectral-domain device. Foveal thickness and macular volume were measured in the foveal region and in the parafoveal and perifoveal regions in the temporal, superior, nasal, and inferior quadrants. RNFL (retinal nerve fiber layer) was measured in temporal, superior, nasal, and inferior quadrants. Ganglion cell complex (GCC) was evaluated in the superior and inferior quadrants. Using the UPDRS clinical scale, the relationship between measurements and the differences between the control group and the patient group were evaluated. Results: Among the OCT values in our study, foveal, parafoveal, perifoveal thickness, macular volume, RNFL, and GCC measurements were performed for the right and left eyes, and no difference was found between the patient group and the control group. There was no difference in VEP amplitude and latency values between the patient and control groups. The relationships between UPDRS and modified Hoehn Yahr staging and OCT and VEP measurements in the patient revealed no correlation. Conclusions: Studies on whether OCT measurements can functionally be a marker or which segments are more valuable for disease progression in patients with PD are needed. Visual dysfunction in PD cannot be attributed only to retinal pathology; however, the retina may provide monitoring of the status of dopaminergic neurodegeneration and axonal loss in PD.

Sunitinib induced colitis manifesting as invasive diarrhea in a patient with renal cell carcinoma.

INTRODUCTION: Sunitinib is a tyrosine kinase inhibitor that binds to vascular endothelial factor receptor currently used for the treatment of renal cell carcinoma, as well as for several other conditions such as gastrointestinal stromal tumors and pancreatic neuroendocrine tumors. We present a patient with invasive diarrhea who was treated with sunitinib for metastatic renal cell carcinoma. CASE REPORT: Drug induced colitis was confirmed with colonoscopy from histopathological specimens. Clinical recovery of diarrhea was achieved with oral budesonide. Remarkably, the pathologic findings were observed in both the macroscopically normal mucosa and the mucosa with aphthous ulcers in the colon. MANAGEMENT & OUTCOME: The patient was treated for sunitinib associated diarrhea, after exclusion of the other reasons. Metronidazole and piperacillin/tazobactam treatment were prescribed. DISCUSSION: Diarrhea is a frequent symptom in patients treated with tyrosine kinase inhibitors, however the described pathologic findings have rarely been reported. Our aim is to emphasize the importance of close follow-up in patients treated with tyrosine kinase inhibitors, and to raise awareness on the management of sunitinib induced colitis.

Event-Related Potentials Elicited by Face and Face Pareidolia in Parkinson's Disease.

BACKGROUND: Parkinson's disease is associated with impaired ability to recognize emotional facial expressions. In addition to a visual processing disorder, a visual recognition disorder may be involved in these patients. Pareidolia is a type of complex visual illusion that permits the interpretation of a vague stimulus as something known to the observer. Parkinson's patients experience pareidolic illusions. N170 and N250 waveforms are two event-related potentials (ERPs) involved in emotional facial expression recognition. OBJECTIVE: In this study, we investigated how Parkinson's patients process face and face-pareidolia stimuli at the neural level using N170, vertex positive potential (VPP), and N250 components of event-related potentials. METHODS: To examine the response of face and face-pareidolia processing in Parkinson's patients, we measured the N170, VPP, and N250 components of the event-related brain potentials in a group of 21 participants with Parkinson's disease and 26 control participants. RESULTS: We found that the latencies of N170 and VPP responses to both face and face-pareidolia stimuli were increased along with their amplitudes, and the amplitude of N250 responses decreased in Parkinson's patients compared to the control group. In both control and Parkinson's patients, face stimuli generated greater ERP amplitude and shorter latency in responses than did face-pareidolia stimuli. CONCLUSION: The results of our study showed that ERPs associated with face and also face-pareidolia stimuli processing are changed in early-stage neurophysiological activity in the temporoparietal cortex of Parkinson's patients.

Changes in face and face pareidolia processing in patients with migraine: an ERP study.

Migraine is a multifactorial brain disorder characterized by recurrent disabling headache attacks. One of the possible mechanisms in the pathogenesis of migraine may be a decrease in inhibitory cortical stimuli in the primary visual cortex attributable to cortical hyperexcitability. The aim of this study was to investigate the neural correlates underlying face and face pareidolia processing in terms of the event-related potential (ERP) components, N170, vertex positive potential (VPP), and N250, in patients with migraine. In total, 40 patients with migraine without aura, 23 patients with migraine and aura, and 30 healthy controls were enrolled. We recorded ERPs during the presentation of face and face pareidolia images. N170, VPP, and N250 mean amplitudes and latencies were examined. N170 was significantly greater in patients with migraine with aura than in healthy controls. VPP amplitude was significantly greater in patients with migraine without aura than in healthy controls. The face stimuli evoked significantly earlier VPP responses to faces (168.7 ms, SE = 1.46) than pareidolias (173.4 ms, SE = 1.41) in patients with migraine with aura. We did not find a significant difference between N250 amplitude for face and face pareidolia processing. A significant difference was observed between the groups for pareidolia in terms of N170 [F(2,86) = 14,75, P < 0.001] and VPP [F(2,86) = 16.43, P < 0.001] amplitudes. Early ERPs are a valuable tool to study the neural processing of face processing in patients with migraine to demonstrate visual cortical hyperexcitability.NEW & NOTEWORTHY Event-related potentials (ERPs) are important for understanding face and face pareidolia processing in patients with migraine. N170, vertex positive potential (VPP), and N250 ERPs were investigated. N170 was revealed as a potential component of cortical excitability for face and face pareidolia processing in patients with migraine.

Dynamic thiol-disulphide homeostasis in patients with Guillain-Barre Syndrome.

OBJECTIVE: The aim of this study was to evaluate dynamic thiol-disulphide homeostasis as a novel oxidative stress parameter in patients with Guillain-Barre syndrome (GBS). METHODS: A total of 130 participants were included in this study, 70 of whom were diagnosed with GBS. Total thiol (-SH+-S-S-) and native thiol (-SH) levels in serum were measured in all patients and healthy individuals. Amount of dynamic disulphide bond were calculated from these values. In the GBS patients, disability status was determined by the Hughes and Medical Research Center (MRC) sum scores at the time of admission and 3 months thereafter. RESULTS: Total and native thiol levels were significantly lower in patients with GBS compared with healthy individuals. There was no statistically significant difference in the number of dynamic disulphide bonds between groups. There was a negative correlation between total thiol levels in patients with GBS and Hughes scores at month 3. DISCUSSION: Oxidative stress is among the molecular changes underlying the pathogenesis of GBS. In this study, we have investigated the dynamic thiol-disulfide homeostasis in patients with epilepsy using a new method in the literature. Also, functional recovery in Guillain-Barré syndrome patients could be promoted by increasing antioxidant activity.

Relationship between thiol-disulphide homeostasis and visual evoked potentials in patients with multiple sclerosis.

PURPOSE: To examine the thiol-disulphide homeostasis during an optic neuritis episode in patients with multiple sclerosis and the relationship between this homeostasis and P100 wave latency. MATERIALS AND METHOD: Visual evoked potential reviews of multiple sclerosis patients who presented with an optic neuritis episode were conducted and P100 latencies were measured. Peripheral blood samples were collected from all patients. Native thiol and total thiol concentrations were measured with the automated method that was recently developed. Their amount of disulphide bonds, disulphide/native thiol, disulphide/total thiol and native thiol/total thiol ratios were calculated. The relationship between P100 latency and thiol-disulphide homeostasis was investigated. RESULTS: A significant positive correlation was determined between the disulphide/native thiol ratio and both mean P100 latency and maximum P100 latency (p = 0.021, r = 0.136; p = 0.030, r = 0.177, respectively). DISCUSSION: As the balance of the plasma dominated by antioxidants moves towards the oxidant side, in other words as a higher rate of thiol is oxidised from the thiol pool, P100 latency is extended. N-acetylcysteine and alpha lipoic acid as well as thiol supplements can improve the thiol-disulphide balance, reinforce antioxidant defence and it can help in slowing down the demyelinating damage.

Thiol-Disulfide Homeostasis in Cerebral Venous Sinus Thrombosis.

BACKGROUND: The objective of this study is to examine thiol-disulfide homeostasis in patients with cerebral venous sinus thrombosis. METHODS: Fifty-three patients diagnosed with cerebral venous sinus thrombosis and 80 healthy volunteers were included in the study. The native thiol and total thiol concentrations were measured with the newly developed automated method. In addition, their amount of disulfide bonds was calculated. RESULTS: The total thiol and native thiol levels of the patients with cerebral venous sinus thrombosis were significantly lower than the healthy volunteers (p = 0.001, p = 0.001, respectively). In terms of dynamic disulfide bond formation, there was no statistically significant difference between the groups (p > 0.05). A significant negative correlation was determined between native thiol and total thiol levels and the number of sinuses that had thrombosis (r = -0.136, p = 0.033; r = -0.141, p = 0.015, respectively). There was no correlation between National Institutes of Health Stroke Scale score and thiol-disulfide homeostasis parameters. CONCLUSIONS: This study is the first study to examine thiol-disulfide homeostasis in patients with cerebral venous sinus thrombosis. The thiol-disulfide balance is impaired under oxidative stress. This study revealed that this balance is disrupted in correlation with widespread thrombosis in patients with cerebral venous sinus thrombosis. Therefore, fortification of thiol deficiency with N-acetyl cysteine or alpha-lipoic acid can prevent the progress of thrombosis and can be beneficial in cerebral venous sinus thrombosis treatment.

Impaired thiol-disulphide homeostasis in patients with axonal polyneuropathy.

OBJECTIVE: The objective of this study is to examine thiol-disulphide homeostasis in patients with polyneuropathy dominated by diabetic or non-diabetic axonal degeneration. MATERIALS-METHODS: Fifty-four patients diagnosed with polyneuropathy dominated by axonal damage and 41 healthy subjects were included in the study. The patients were grouped into two groups according to whether or not they had diabetes. The native thiol and total thiol concentrations were measured with the newly developed automated method. RESULTS: While there was no significant difference between the patients with diabetic and non-diabetic polyneuropathy in terms of native thiol and total thiol levels (p > 0.05), the native thiol and total thiol levels of the groups with both diabetic polyneuropathy and non-diabetic polyneuropathy were significantly low compared to the control group (p < 0.01). The level of disulphides in the patients with diabetic polyneuropathy was significantly higher than that of the patients with non-diabetic polyneuropathy and the healthy individuals (p < 0.05). The loss in the sural nerve sensory neural action potential amplitude was positively correlated with the decrease in the levels of both native thiol and total thiol (p < 0.05). DISCUSSION: In our study, we observed that the thiol-disulphide balance was also impaired in patients with non-diabetic polyneuropathy similar to patients with diabetic polyneuropathy, and we therefore considered that impaired the thiol-disulphide homeostasis could be the last common path in patients with polyneuropathy with axonal damage, regardless of the aetiology. Therefore, fortification of thiol deficiency with N-acetyl cysteine or alpha-lipoic acid can fix the thiol-disulphide balance and help decelerate the axonal damage.

Impairment of dynamic thiol-disulphide homeostasis in patients with idiopathic Parkinson's disease and its relationship with clinical stage of disease.

OBJECTIVE: The aim of this study was to investigate dynamic thiol-disulphide homeostasis in patients with idiopathic Parkinson's disease and to determine its relationship with the clinical stage as assessed by the modified Hoehn and Yahr scale. DESIGN AND METHODS: Fifty-two patients with Parkinson's disease (PD), diagnosed according to the United Kingdom Brain Bank Criteria for idiopathic PD, and 41 healthy individuals were included in the study. Clinical staging of patients was performed according to the Hoehn and Yahr scale. Peripheral blood samples were taken from all participants, and their native thiol and total thiol concentrations were measured using the newly developed automated method. In addition, their amount of disulphide bonds, disulphide/native thiol, disulphide/total thiol and native thiol/total thiol ratios were calculated. RESULTS: Considering the data obtained from Parkinson's patients and the control group, both native thiol (-SH) and total thiol (-SH+-S-S) levels were found significantly lower in patients with Parkinson's disease. A negative and statistically significant relationship was found between both disease duration and disease stage and native thiol (-SH), total thiol (-SH+-S-S) levels and -SH/(-SH+-S-S-) ratio. A positive and statistically significant relationship was found between both disease duration and stage and -S-S-/-SH and -S-S-/(-SH+-S-S-) ratios. CONCLUSION: In patients with Parkinson's disease, dynamic thiol-disulphide homeostasis is disrupted, according to disease stage and duration. This balance, easily measured by using the newly developed automated method, can be used in monitoring disease progression. To our knowledge, our study will be the first report in the literature.

The Prevalence of Dry Eye and Sjögren Syndrome in Patients with Migraine.

PURPOSE: To evaluate the presence of dry eye and primary Sjögren syndrome (SS) in patients with migraine. METHODS: In total, 46 eyes of 46 patients with migraine (group 1) and 50 eyes of 50 healthy subjects (group 2) were included in this study. Detailed ophthalmologic, neurologic and rheumatologic examination were performed on all participants. Ocular surface disease index questionnaire, tear function tests, visual analog scale for pain, serologic analysis were also performed. RESULTS: Dry eye symptoms and findings were significantly higher and more severe in group 1 when compared with group 2. Primary SS was not found in any of the participants. The migraine lifetime duration was negatively correlated with the tear function tests while it was positively correlated with the ocular surface disease index scores. CONCLUSIONS: Dry eye symptoms and findings are higher in migraine patients when compared with the healthy subjects without the presence of Sjögren syndrome.

A novel oxidative stress marker in migraine patients: dynamic thiol-disulphide homeostasis.

The aim of this study was to investigate dynamic thiol-disulphide homeostasis as a novel oxidative stress parameter in migraine patients. A total of 115 participants were included in the study, and 63 of whom were diagnosed with migraine. The total thiol (-SH+-S-S-) and native thiol (-SH) levels in the serum were measured in all patients and healthy individuals. The dynamic disulphide bond (-S-S-) and (-S-S-) × 100/(-SH), (-S-S-) × 100/(-SH+-S-S-), and -SH × 100/(-SH+-S-S-) ratios were calculated from these values. The total and native thiol levels of migraine patients participating in the study were found to be significantly higher than the total and native thiol levels of healthy individuals. No statistically significant difference was determined in terms of the dynamic disulphide bond amounts or (-S-S-) × 100/(-SH), (-S-S-) × 100/(-SH+-S-S-), and -SH × 100/(-SH+-S-S-) ratios. The total thiol, native thiol, and dynamic disulphide bond levels, and (-S-S-) × 100/(-SH), (-S-S-) × 100/(-SH+-S-S-), and -SH × 100/(-SH+-S-S-) ratios were not correlated with attack frequency, pain intensity, or migraine type. Oxidative stress is considered to be one of the molecular changes underlying the pathogenesis of migraine.

A novel oxidative stress marker in patients with Alzheimer's disease: dynamic thiol-disulphide homeostasis.

OBJECTIVE: The aim of this study was to evaluate the dynamic thiol-disulphide homeostasis as an oxidative stress parameter, using a newly proposed method, in patients with Alzheimer's disease. METHODS: In total, 97 participants were included in the study. Among them, 51 had been diagnosed with Alzheimer's disease, and the remaining 46 were healthy individuals. Total thiol (-SH+-S-S-) levels and native thiol (-SH) levels in serum of each participant were measured. The amount of dynamic disulphide bonds (-S-S-) and (-S-S-) ×100/(-SH), (-S-S-) ×100/(-SH+-S-S-), and -SH×100/(-SH+-S-S-) ratios were calculated from these values. The obtained data were used to compare Alzheimer's disease patients with healthy individuals. RESULTS: The average total thiol and native thiol levels of patient with Alzheimer's disease in the study were found to be significantly lower than those levels of healthy individuals. In addition, in the patient group, the -S-S-×100/-S-S+-SH ratio was found to be significantly higher, whereas the -SH×100/-S-S+-SH ratio was found to be significantly lower compared with healthy individuals. Total thiol and native thiol levels, dynamic disulphide bond amount, and -S-S-×100/-SH, -S-S-×100/-S-S+-SH, and -SH×100/-S-S+-SH ratios were not found to be correlated with mini mental state examination score or duration of disease. CONCLUSION: Recent studies have shown that oxidative stress is the one of the molecular changes underlying the pathogenesis of Alzheimer's disease. In this study, we have investigated the dynamic thiol-disulphide homeostasis in patients with Alzheimer's disease, using a novel method.

Dynamic thiol-disulfide homeostasis in acute ischemic stroke patients.

Dynamic thiol-disulfide homeostasis plays a critical role in the cellular protection provided by antioxidation. The aim of this study was to investigate whether there is a change in thiol-disulfide homeostasis in acute ischemic stroke patients. Patients diagnosed with acute ischemic stroke that had undergone magnetic resonance diffusion-weighted imaging within the first 24 h were prospectively included in this study. The thiol, disulfide, and total thiol levels were measured during the first 24 and 72 h, and the National Institutes of Health Stroke Scale (NIHSS), modified Rankin Scale (mRS), and Barthel Index (BI) of the patients were recorded. Overall, the relationships between the thiol-disulfide levels of the patients and the infarct volumes, NIHSS, mRS, and BI scores were investigated. In this study, 54 patients and 53 healthy controls were included. The mean of the native thiol levels in the stroke group was 356.572 ± 61.659 µmol/L (min/max 228.00/546.40), while it was 415.453 ± 39.436 µmol/L (min/max 323.50/488.70) in the control group (p < 0.001). A negative, significant correlation was observed between the infarct volumes and native thiol levels (ρ = -0.378; p = 0.005), and the disulfide levels were similar between the groups (Z = 0.774; p = 0.439). Significant difference was found between the thiol levels of the mild and moderate-severe NIHSS groups (p = 0.026). The changes in the thiol levels under oxidative stress may be associated with the severity of the stroke. Substitution of thiol deficiency and correction of thiol-disulfide imbalance may be beneficial in ischemic stroke.

Rhabdomyolysis related to dyskinesia in Parkinson's disease.

Rhabdomyolysis is a life threatening syndrome. It accounts for an estimated 8% to 15% of cases of acute renal failure and is associated with a mortality rate of 5%. In movement disorders, various causes of rhabdomyolysis have been reported including status dystonicus, myoclonus, generalized chorea and parkinsonism-hyperprexia syndrome in Parkinson's disease (PD). Levodopa-induced dyskinesia leading to rhabdomyolysis is a very rare phenomenon in PD. We report a case of 76 years old PD patient with dyskinesia and rhabdomyolysis.

Acute cerebral ischaemia: relationship between serum and cerebrospinal fluid orexin-A concentration and infarct volume.

OBJECTIVE: Orexins are hypothalamic neuropeptides that are involved in feeding, neuroendocrine regulation, sleep-wakefulness and sleep disorders (such as narcolepsy). This study investigated the relationship between serum and cerebrospinal fluid (CSF) orexin-A concentrations and infarct volume, in patients with ischaemic stroke. METHODS: Serum and CSF concentrations of orexin-A were determined 48-72 h after the onset of ischaemic stroke in patients, then compared with those of healthy control subjects of comparable age. Infarct volumes were measured using computerized tomography, 48-72 h after hospitalization. RESULTS: Mean serum and CSF orexin-A concentrations were significantly lower among ischaemic stroke patients (n = 29) compared with control subjects (n = 13). There was a significant inverse correlation between infarct volumes and CSF orexin-A concentrations in patients with ischaemic stroke. CONCLUSION: These data show that serum and CSF orexin-A concentrations decrease after cerebral ischaemia and may play a role in the development of brain injury. The orexin-A concentration in the CSF might be a useful biomarker for the assessment of progression of brain tissue damage during the early stages of ischaemic stroke.

The effect of local corticosteroid injection on F-wave conduction velocity and sympathetic skin response in carpal tunnel syndrome.

The aim of this study was to evaluate the efficacy of steroid injection for the treatment of the carpal tunnel syndrome (CTS), with F-wave parameters and sympathetic skin response (SSR). Seventeen hands of 10 women patients were treated with local steroid injection with 2-month follow-up. All patients underwent single injection into the carpal tunnel. Response to injection was measured nerve conduction studies (NCSs), median nerve F waves, and SSR before and after treatment. To determine the normal values, 42 hands of 21 healthy women were also studied. There was a significant improvement of sensory and motor nerve conduction values when compared to baseline values (P < 0.01). At the end of follow-up period, the median sensory distal latency and the sensory latency differences between the median and the ulnar nerve were improved 35 and 65%, respectively. The maximum, mean F-wave amplitudes and chronodispersion showed a slight improvement with respect to baseline values and controls, but statistical significance was not achieved after treatment. Although no statistically significant improvements were observed in SSR parameters, slightly decreased amplitudes and increased habituation of SSR were noted at the end of the treatment. The present study shows that the local steroid injection results in improvement in NCSs values, but the F-wave parameters were not effectual in short-term outcome of CTS treatment. These findings suggest that the sensory latency differences between the median and the ulnar wrist-to-digit 4 are better parameters in the median nerve recovery after treatment than the median sensory distal latency. Furthermore, the SSR does not seem to be a sensitive method in follow-up of CTS treatment.