30 results on '"Velioglu HA"'
Search Results
2. Hippocampal connectivity dynamics and volumetric alterations predict cognitive status in migraine: A resting-state fMRI study.
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Cankaya S, Ayyildiz B, Sayman D, Duran U, Ucak D, Karaca R, Ayyildiz S, Oktem EO, Lakadamyalı H, Sayman C, Ozsimsek A, Yalçınkaya A, Hanoglu L, Velioglu HA, and Yulug B
- Abstract
The etiology of cognitive decline linked to migraine remains unclear, with a growing recurrence rate and potential increased dementia risk among sufferers. Cognitive dysfunction has recently gained attention as a significant problem among migraine sufferers that can be related to alterations in hippocampal function and structure. This study explores hippocampal subfield connectivity and volume changes in migraine patients. We recruited 90 individuals from Alanya University's Neurology Department, including 49 migraine patients and 41 controls, for functional and anatomical imaging. Using the CONN toolbox and FreeSurfer, we assessed functional connectivity and subfield volumes, respectively. Montreal Cognitive Assessment (MOCA) was used to assess cognition in the entire sample. As a result, migraine patients exhibited significantly lower MOCA scores compared to controls (p<.001). Also, we found significant differences in hippocampal subfields between migraine patients and control groups in terms of functional connectivity after adjusting for years of education; here we showed that the left CA3 showed higher connectivity with right MFG and right occipitolateral cortex. Furthermore, the connectivity of left fimbria with the left temporal lobe and hippocampus and the connectivity of the right hippocampal-tail with right insula, heschl's gyrus, and frontorbital cortex were lower in the migraineurs. Additionally, volumes of specific hippocampal subfields were significantly lower in the migraineurs (whole hippocampus p = 0.004, whole hippocampus head p = 0.003, right CA1 head p = 0.006, and right HATA p = 0.005) compared to controls. In conclusion, these findings indicate that migraine-associated cognitive impairment involves significant functional and structural brain changes, particularly in the hippocampus, which may heighten dementia risk. This pioneering study unveils critical hippocampal alterations linked to cognitive function in migraine sufferers, underscoring the potential for these changes to impact dementia development., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier Inc.)
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- 2024
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3. Parietal memory network and memory encoding versus retrieval impairments in PD-MCI patients: A hippocampal volume and cortical thickness study.
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Sahin S, Velioglu HA, Yulug B, Bayraktaroglu Z, Yildirim S, and Hanoglu L
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- Humans, Male, Female, Aged, Middle Aged, Parietal Lobe pathology, Parietal Lobe diagnostic imaging, Atrophy pathology, Cerebral Cortex diagnostic imaging, Cerebral Cortex pathology, Brain Cortical Thickness, Hippocampus pathology, Hippocampus diagnostic imaging, Parkinson Disease pathology, Parkinson Disease diagnostic imaging, Parkinson Disease complications, Cognitive Dysfunction pathology, Cognitive Dysfunction diagnostic imaging, Cognitive Dysfunction physiopathology, Cognitive Dysfunction etiology, Mental Recall physiology, Memory Disorders etiology, Memory Disorders pathology, Memory Disorders diagnostic imaging, Magnetic Resonance Imaging
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Objective: The pathophysiology behind memory impairment in Parkinson's Disease Mild Cognitive Impairment (PD-MCI) is unclear. This study aims to investigate the hippocampal and cortical atrophy patterns in PD-MCI patients with different types of memory impairments, categorized as Retrieval Failure (RF) and Encoding Failure (EF)., Methods: The study included 16 healthy controls (HC) and 34 PD-MCI patients, divided into RF (N = 18) and EF (N = 16) groups based on their Verbal Memory Processes Test (VMPT) scores, including spontaneous recall, recognition, and Index of Sensitivity to Cueing (ISC). Hippocampal subfields and cortical thicknesses were measured using the FreeSurfer software for automatic segmentation., Results: Compared to the HC group, the EF group exhibited significant atrophy in the left lateral occipital region and the right caudal middle frontal, superior temporal, and inferior temporal regions (p⟨0.05). The RF group displayed significant atrophy in the left lateral occipital, middle temporal, and precentral regions, as well as the right pars orbitalis and superior frontal regions (p⟨0.05). Hippocampal subfield analysis revealed distinct volume differences between HC-EF and RF-EF groups, with significant reductions in the CA1, CA3, and CA4 subregions in the EF group, but no differences between HC and RF groups (p > 0.05)., Conclusion: Gray matter atrophy patterns differ in PD-MCI patients with encoding and retrieval memory impairments. The significant hippocampal atrophy in the EF group, particularly in the CA subregions, highlights its potential role in disease progression and memory decline. Additionally, the convergence of atrophy in the lateral occipital cortex across both RF and EF groups suggests the involvement of the Parietal Memory Network (PMN) in PD-related memory impairment., (© 2024 The Author(s). CNS Neuroscience & Therapeutics published by John Wiley & Sons Ltd.)
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- 2024
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4. Smoking affects global and regional brain entropy in depression patients regardless of depression: Preliminary findings.
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Velioglu HA, Yıldız S, Ozdemir-Oktem E, Cankaya S, Lundmark AK, Ozsimsek A, Hanoglu L, and Yulug B
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- Humans, Male, Female, Adult, Middle Aged, Entropy, Nerve Net diagnostic imaging, Nerve Net physiopathology, Young Adult, Depressive Disorder, Major physiopathology, Depressive Disorder, Major diagnostic imaging, Magnetic Resonance Imaging, Smoking epidemiology, Brain diagnostic imaging, Brain physiopathology
- Abstract
Objective: This study examines the effect of smoking on global and regional brain entropy in patients with Major Depressive Disorder (MDD), aiming to elucidate the relationship between smoking habits and brain network complexity in depression., Methods: The study enrolled 24 MDD patients, divided into smokers and non-smokers, from Alanya Alaaddin Keykubat University and Istanbul Medipol University. Resting-state fMRI data were acquired and processed. The complexity of neuronal activity was assessed using dispersion entropy, with statistical significance determined by a suite of tests including Kolmogorov-Smirnov, Student's t-test, and Mann-Whitney U test., Results: The smoking cohort exhibited higher global brain entropy compared to the non-smoking group (p = 0.033), with significant differences in various brain networks, indicating that smoking may alter global brain activity and network dynamics in individuals with MDD., Conclusion: The study provides evidence that smoking is associated with increased brain entropy in MDD patients, suggesting that chronic smoking may influence cognitive and emotional networks. This underscores the importance of considering smoking history in the treatment and prognosis of MDD. The findings call for further research to understand the mechanistic links between smoking, brain entropy, and depression., Competing Interests: Declaration of competing interest All contributing authors have declared no potential conflicts of interest., (Copyright © 2024. Published by Elsevier Ltd.)
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- 2024
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5. Retraction notice to "Combined metabolic activators improve metabolic functions in the animal models of neurodegenerative diseases" [Life Sci. 314 (2023) 121325].
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Turkez H, Altay O, Yildirim S, Li X, Yang H, Bayram C, Bolat I, Oner S, Tozlu OO, Arslan ME, Arif M, Yulug B, Hanoglu L, Cankaya S, Lam S, Velioglu HA, Coskun E, Idil E, Nogaylar R, Ozsimsek A, Hacimuftuoglu A, Shoaie S, Zhang C, Nielsen J, Borén J, Uhlén M, and Mardinoglu A
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- 2024
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6. Correction: Altered blood parameters in "major depression" patients receiving repetitive transcranial magnetic stimulation (rTMS) therapy: a randomized case-control study.
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Ozkan BN, Bozali K, Boylu ME, Velioglu HA, Aktas S, Kirpinar I, and Guler EM
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- 2024
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7. Altered blood parameters in "major depression" patients receiving repetitive transcranial magnetic stimulation (rTMS) therapy: a randomized case-control study.
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Ozkan BN, Bozali K, Boylu ME, Velioglu HA, Aktas S, Kirpinar I, and Guler EM
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- Humans, Male, Female, Adult, Case-Control Studies, Middle Aged, S100 Calcium Binding Protein beta Subunit blood, Glial Cell Line-Derived Neurotrophic Factor blood, Antioxidants metabolism, Sulfhydryl Compounds blood, Depressive Disorder, Major therapy, Depressive Disorder, Major blood, Transcranial Magnetic Stimulation methods, Oxidative Stress, Brain-Derived Neurotrophic Factor blood
- Abstract
Major depressive disorder (MDD) is a debilitating illness that includes depressive mood. Repetitive Transcranial Magnetic Stimulation (rTMS) is a therapy method used in the treatment of MDD. The purpose of this study was to assess neurotrophic factors, and oxidative stress levels in MDD patients and evaluate the changes in these parameters as a result of rTMS therapy. Twenty-five patients with MDD and twenty-six healthy volunteers with the same demographic characteristics were included in the study. Brain-derived neurotrophic factors were measured photometrically with commercial kits. Oxidative stress parameters were measured by the photometric method. Oxidative stress index (OSI) and disulfide (DIS) levels were calculated with mathematical formulas. In this study, total antioxidant status (TAS), total thiol (TT), and native thiol (NT) antioxidant parameters and brain-derived neurotrophic factor (BDNF), glial cell line-derived neurotrophic factor (GDNF), and allopregnanolone (ALLO) levels were reduced in pre-rTMS with regard to the healthy control group; TOS, OSI, DIS, and S100 calcium-binding protein B (S100B) levels were increased statistically significantly (p < 0.01). Moreover, owing to TMS treatment; TAS, TT, NT, BDNF, GDNF, and ALLO levels were increased compared to pre-rTMS, while DIS, TOS, OSI, and S100B levels were decreased significantly (p < 0.01). The rTMS treatment reduces oxidative stress and restores thiol-disulfide balance in MDD patients. Additionally, rTMS modulates neurotrophic factors and neuroactive steroids, suggesting its potential as an antidepressant therapy. The changes in the biomarkers evaluated may help determine a more specific approach to treating MDD with rTMS therapy., (© 2024. The Author(s).)
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- 2024
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8. Diabetes-related clinical and microstructural white matter changes in patients with Alzheimer's disease.
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Sumbul-Sekerci B, Velioglu HA, and Sekerci A
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- Humans, Male, Female, Aged, Retrospective Studies, Brain diagnostic imaging, Brain pathology, Middle Aged, Aged, 80 and over, Creatine metabolism, Alzheimer Disease pathology, Alzheimer Disease diagnostic imaging, White Matter diagnostic imaging, White Matter pathology, Diabetes Mellitus, Type 2 pathology, Diabetes Mellitus, Type 2 complications, Diabetes Mellitus, Type 2 diagnostic imaging, Diffusion Tensor Imaging
- Abstract
Aim: Although there exists substantial epidemiological evidence indicating an elevated risk of dementia in individuals with diabetes, our understanding of the neuropathological underpinnings of the association between Type-2 diabetes mellitus (T2DM) and Alzheimer's disease (AD) remains unclear. This study aims to unveil the microstructural brain changes associated with T2DM in AD and identify the clinical variables contributing to these changes., Methods: In this retrospective study involving 64 patients with AD, 31 individuals had concurrent T2DM. The study involved a comparative analysis of diffusion tensor imaging (DTI) images and clinical features between patients with and without T2DM. The FSL FMRIB software library was used for comprehensive preprocessing and tractography analysis of DTI data. After eddy current correction, the "bedpost" model was utilized to model diffusion parameters. Linear regression analysis with a stepwise method was used to predict the clinical variables that could lead to microstructural white matter changes., Results: We observed a significant impairment in the left superior longitudinal fasciculus (SLF) among patients with AD who also had T2DM. This impairment in patients with AD and T2DM was associated with an elevation in creatine levels., Conclusion: The white matter microstructure in the left SLF appears to be sensitive to the impairment of kidney function associated with T2DM in patients with AD. The emergence of AD in association with T2DM may be driven by mechanisms distinct from the typical AD pathology. Compromised renal function in AD could potentially contribute to impaired white matter integrity., (© 2024 The Authors. Brain and Behavior published by Wiley Periodicals LLC.)
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- 2024
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9. The functional role of the pulvinar in discriminating between objective and subjective cognitive impairment in major depressive disorder.
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Yulug B, Ayyildiz S, Sayman D, Karaca R, Ipek L, Cankaya S, Salar AB, Ayyildiz B, Mikuta C, Yagci N, Oktem EO, Ozsimsek A, Velioglu HA, and Hanoglu L
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Introduction: Emotionally driven cognitive complaints represent a major diagnostic challenge for clinicians and indicate the importance of objective confirmation of the accuracy of depressive patients' descriptions of their cognitive symptoms., Methods: We compared cognitive status and structural and functional brain connectivity changes in the pulvinar and hippocampus between patients with total depression and healthy controls. The depressive group was also classified as "amnestic" or "nonamnestic," based on the members' subjective reports concerning their forgetfulness. We then sought to determine whether these patients would differ in terms of objective neuroimaging and cognitive findings., Results: The right pulvinar exhibited altered connectivity in individuals with depression with objective cognitive impairment, a finding which was not apparent in depressive patients with subjective cognitive impairment., Discussion: The pulvinar may play a role in depression-related cognitive impairments. Connectivity network changes may differ between objective and subjective cognitive impairment in depression and may play a role in the increased risk of dementia in patients with depression., Competing Interests: The authors declare no conflicts of interest. Author disclosures are available in the Supporting information., (© 2024 The Authors. Alzheimer's & Dementia: Translational Research & Clinical Interventions published by Wiley Periodicals LLC on behalf of Alzheimer's Association.)
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- 2024
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10. rTMS reduces delta and increases theta oscillations in Alzheimer's disease: A visual-evoked and event-related potentials study.
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Velioglu HA, Dudukcu EZ, Hanoglu L, Guntekin B, Akturk T, and Yulug B
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- Humans, Longitudinal Studies, Evoked Potentials physiology, Electroencephalography, Transcranial Magnetic Stimulation, Alzheimer Disease therapy
- Abstract
Background: Repetitive transcranial magnetic stimulation (rTMS) has emerged as a promising alternative therapy for Alzheimer's disease (AD) due to its ability to modulate neural networks and enhance cognitive function. This treatment offers the unique advantage of enabling real-time monitoring of immediate cognitive effects and dynamic brain changes through electroencephalography (EEG)., Objective: This study focused on exploring the effects of left parietal rTMS stimulation on visual-evoked potentials (VEP) and visual event-related potentials (VERP) in AD patients., Methods: Sixteen AD patients were recruited for this longitudinal study. EEG data were collected within a Faraday cage both pre- and post-rTMS to evaluate its impact on potentials., Results: Significant alterations were found in both VEP and VERP oscillations. Specifically, delta power in VEP decreased, while theta power in VERP increased post-rTMS, indicating a modulation of brain activities., Discussion: These findings confirm the positive modulatory impact of rTMS on brain activities in AD, evidenced by improved cognitive scores. They align with previous studies highlighting the potential of rTMS in managing hyperexcitability and oscillatory disturbances in the AD cortex., Conclusion: Cognitive improvements post-rTMS endorse its potential as a promising neuromodulatory treatment for cognitive enhancement in AD, thereby providing critical insights into the neurophysiological anomalies in AD and possible therapeutic avenues., (© 2024 The Authors. CNS Neuroscience & Therapeutics published by John Wiley & Sons Ltd.)
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- 2024
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11. EGb 761 reduces Ca 2+ influx and apoptosis after pentylenetetrazole treatment in a neuroblastoma cell line.
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Ovey IS, Ozsimsek A, Velioglu HA, Altay O, Mardinoglu A, and Yulug B
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Background: Transient receptor potential (TRP) channels have been found to have significant implications in neuronal outgrowth, survival, inflammatory neurogenic pain, and various epileptogenic processes. Moreover, there is a growing body of evidence indicating that transient receptor potential (TRP) channels have a significant impact on epilepsy and its drug-resistant subtypes., Objective: We postulated that E Gb 761 would modulate TRPA1 channels, thereby exhibiting anti-inflammatory and neuroprotective effects in a neuroblastoma cell line. Our rationale was to investigate the impact of EGb 761 in a controlled model of pentylenetetrazole-induced generalized epilepsy., Methodology: We evaluated the neuroprotective, antioxidant and anti-apoptotic effects of E Gb 761 both before and after the pentylenetetrazole application in a neuroblastoma cell line. Specifically, we focused on the effects of EGB 761 on the activity of Transient receptor potential (TRP) channels., Results: EGb 761 applications both before and after the pentylenetetrazole incubation period reduced Ca release and restored apoptosis, ROS changes, mitochondrial depolarization and caspase levels, suggesting a prominent prophylactic and therapeutic effect of E Gb 761 in the pentylenetetrazole-induced epileptogenesis process., Conclusion: Our basic mechanistic framework for elucidating the pathophysiological significance of fundamental ion mechanisms in a pentylenetetrazole treated neuroblastoma cell line provided compelling evidence for the favorable efficacy and safety profile of Egb 761 in human-relevant in vitro model of epilepsy. To the best of our knowledge, this is the first study to investigate the combined effects of EGb 761 and pentylenetetrazole on TRP channels and measure their activation level in a relevant model of human epileptic diseases., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Ovey, Ozsimsek, Velioglu, Altay, Mardinoglu and Yulug.)
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- 2023
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12. Infection with COVID-19 is no longer a public emergency: But what about degenerative dementia?
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Yulug B, Ayyıldız B, Ayyıldız S, Sayman D, Salar AB, Cankaya S, Ozdemir Oktem E, Ozsimsek A, Kurt CC, Lakadamyalı H, Akturk A, Altay Ö, Hanoglu L, Velioglu HA, and Mardinoglu A
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- Humans, Hippocampus, Public Health, COVID-19 complications, Alzheimer Disease epidemiology, Cognition Disorders
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Although no longer considered a public health threat, post-COVID cognitive syndrome continues to impact on a considerable proportion of individuals who were infected with COVID-19. Recent studies have also suggested that COVID may be represent a critical risk factor for the development of Alzheimer's disease (AD). We compared 17 COVID patients with 20 controls and evaluated the effects of COVID-19 on general cognitive performance, hippocampal volume, and connections using structural and seed-based connectivity analysis. We showed that COVID patients exhibited considerably worse cognitive functioning and increased hippocampal connectivity supported by the strong correlation between hippocampal connectivity and cognitive scores. Our findings of higher hippocampal connectivity with no observable hippocampal morphological changes even in mild COVID cases may be represent evidence of a prestructural compensatory mechanism for stimulating additional neuronal resources to combat cognitive dysfunction as recently shown for the prodromal stages of degenerative cognitive disorders. Our findings may be also important in light of recent data showing that other viral infections as well as COVID may constitute a critical risk factor for the development of AD. To our knowledge, this is the first study that investigated network differences in COVID patients, with a particular focus on compensatory hippocampal connectivity., (© 2023 Wiley Periodicals LLC.)
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- 2023
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13. A structural and resting-state functional connectivity investigation of the pulvinar in elderly individuals and Alzheimer's disease patients.
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Velioglu HA, Ayyildiz B, Ayyildiz S, Sutcubasi B, Hanoglu L, Bayraktaroglu Z, and Yulug B
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- Humans, Aged, Brain, Gray Matter, Magnetic Resonance Imaging, Alzheimer Disease, Pulvinar diagnostic imaging, Cognition Disorders, Cognitive Dysfunction
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In Alzheimer's disease (AD), structural and functional changes in the brain may give rise to disruption of specific cognitive functions. The aim of this study is to investigate the functional connectivity alterations in the pulvinar's subdivisions and total pulvinar voxel-based morphometry (VBM) changes in individuals with AD and healthy controls. A seed-based functional connectivity analysis was applied to the anterior, inferior, lateral, and medial pulvinar in each hemisphere. Furthermore, VBM analysis was carried out to compare gray matter (GM) volume differences in the pulvinar and thalamus between the two groups. Connectivity analysis revealed that the pulvinar subdivisions had decreased connectivity in individuals with AD. In addition, the pulvinar and thalamus in each hemisphere were significantly smaller in the AD group. The pulvinar may have a role in AD-related cognitive impairments and the intrinsic connectivity network changes and GM loss in pulvinar subdivisions suggest the cognitive deterioration occurring in those with AD. HIGHLIGHTS: The pulvinar may play a role in pathophysiology of cognitive impairments in those with Alzheimer's disease (AD). Decreased structural volume and functional connectivity were found in patients with AD. The inferior pulvinar is functionally the most affected subdivision by AD compared to the others., (© 2022 the Alzheimer's Association.)
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- 2023
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14. Decreased frontal and orbital volumes and increased cerebellar volumes in patients with anosmia Of Unknown origin: A subtle connection?
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Avnioglu S, Sahin C, Cankaya S, Ozen O, Dikici R, Yilmaz H, Velioglu HA, and Yulug B
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- Male, Humans, Female, Adult, Middle Aged, Young Adult, Retrospective Studies, Gray Matter pathology, Cerebellum, Magnetic Resonance Imaging methods, Anosmia pathology, Brain pathology
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Purpose: Neuroimaging studies have shown that anosmia is accompanied by a decreased olfactory bulb volume, yet little is known about alterations in cerebral and cerebellar lobule volumes. The purpose of this study was to investigate structural brain alterations in anosmic patients., Methods: Sixteen anosmic patients (mean age 42.62 ± 16.57 years; 6 women and 10 men) and 16 healthy controls (mean age 43.37 ± 18.98 years; 9 women and 7 men) were included in this retrospective study. All subjects who underwent magnetic resonance imaging scans were analyzed using VolBrain and voxel-based morphometry after olfactory testing., Results: Despite being statistically insignificant, analysis using VBM revealed greater gray matter (GM) and white matter in the anosmia group compared to the healthy subjects. However, decreased GM (p < 0.001) and increased cerebellar (p = 0.046) volumes were observed in the anosmic patients., Conclusions: The study revealed structural brain alterations in specific areas beyond the olfactory bulb. Our results indicate that the cerebellum may play an exceptional role in the olfactory process and that this will be worth evaluating with further dynamic neuroimaging studies., Competing Interests: Declaration of competing interest The authors have no conflict of interest to declare regarding the materials or methods used in this study or the findings presented in this paper., (Copyright © 2023. Published by Elsevier Ltd.)
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- 2023
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15. Brain temperature in healthy and diseased conditions: A review on the special implications of MRS for monitoring brain temperature.
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Yulug B, Velioglu HA, Sayman D, Cankaya S, and Hanoglu L
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- Humans, Temperature, Brain metabolism, Cognition, Amyloid beta-Peptides metabolism, Alzheimer Disease
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Brain temperature determines not only an individual's cognitive functionality but also the prognosis and mortality rates of many brain diseases. More specifically, brain temperature not only changes in response to different physiological events like yawning and stretching, but also plays a significant pathophysiological role in a number of neurological and neuropsychiatric illnesses. Here, we have outlined the function of brain hyperthermia in both diseased and healthy states, focusing particularly on the amyloid beta aggregation in Alzheimer's disease., Competing Interests: Conflict of interest statement We declare that we have no known financial interest or any relationships that could have to affect the work reported in this paper., (Copyright © 2023. Published by Elsevier Masson SAS.)
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- 2023
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16. Exosomes: A missing link between chronic systemic inflammation and Alzheimer's disease?
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Ozansoy M, Mikati H, Velioglu HA, and Yulug B
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- Humans, Neuroinflammatory Diseases, Inflammation metabolism, Alzheimer Disease metabolism, Exosomes metabolism, MicroRNAs genetics, MicroRNAs metabolism
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Exosomes are potent mediators of physiological and pathological processes. In Alzheimer's disease and inflammatory disorders, due to exosomes' distinctive ability to cross the blood-brain barrier, a bidirectional communication between the periphery and the central nervous system exists. Since exosomes can carry various biochemical molecules, this review investigates the role of exosomes as possible mediators between chronic systemic inflammatory diseases and Alzheimer's disease. Exosomes carry pro-inflammatory molecules generated in the periphery, travel to the central nervous system, and target glial and neuronal cells. Microglia and astrocytes then become activated, initiating chronic neuroinflammation. As the aging brain is more susceptible to such changes, this state of neuroinflammation can stimulate neuropathologies, impair amyloid-beta clearance capabilities, and generate dysregulated microRNAs that alter the expression of genes critical in Alzheimer's disease pathology. These processes, individually and collectively, become significant risk factors for the development of Alzheimer's disease., Competing Interests: Conflict of interest statement The authors declare that they have no conflict of interest., (Copyright © 2023. Published by Elsevier Masson SAS.)
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- 2023
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17. Differentiation of claustrum resting-state functional connectivity in healthy aging, Alzheimer's disease, and Parkinson's disease.
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Ayyildiz S, Velioglu HA, Ayyildiz B, Sutcubasi B, Hanoglu L, Bayraktaroglu Z, Yildirim S, Atasever A, and Yulug B
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- Humans, Aged, Gray Matter diagnostic imaging, Magnetic Resonance Imaging methods, Alzheimer Disease, Parkinson Disease, Claustrum, Healthy Aging
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The claustrum is a sheet-like of telencephalic gray matter structure whose function is poorly understood. The claustrum is considered a multimodal computing network due to its reciprocal connections with almost all cortical areas as well as subcortical structures. Although the claustrum has been involved in several neurodegenerative diseases, specific changes in connections of the claustrum remain unclear in Alzheimer's disease (AD), and Parkinson's disease (PD). Resting-state fMRI and T1-weighted structural 3D images from healthy elderly (n = 15), AD (n = 16), and PD (n = 12) subjects were analyzed. Seed-based FC analysis was performed using CONN FC toolbox and T1-weighted images were analyzed with the Computational Anatomy Toolbox for voxel-based morphometry analysis. While we observed a decreased FC between the left claustrum and sensorimotor cortex, auditory association cortex, and cortical regions associated with social cognition in PD compared with the healthy control group (HC), no significant difference was found in alterations in the FC of both claustrum comparing the HC and AD groups. In the AD group, high FC of claustrum with regions of sensorimotor cortex and cortical regions related to cognitive control, including cingulate gyrus, supramarginal gyrus, and insular cortex were demonstrated. In addition, the structural results show significantly decreased volume in bilateral claustrum in AD and PD compared with HC. There were no significant differences in the claustrum volumes between PD and AD groups so the FC may offer more precise findings in distinguishing changes for claustrum in AD and PD., (© 2022 The Authors. Human Brain Mapping published by Wiley Periodicals LLC.)
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- 2023
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18. Combined metabolic activators improve metabolic functions in the animal models of neurodegenerative diseases.
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Turkez H, Altay O, Yildirim S, Li X, Yang H, Bayram C, Bolat I, Oner S, Tozlu OO, Arslan ME, Arif M, Yulug B, Hanoglu L, Cankaya S, Lam S, Velioglu HA, Coskun E, Idil E, Nogaylar R, Ozsimsek A, Hacimuftuoglu A, Shoaie S, Zhang C, Nielsen J, Borén J, Uhlén M, and Mardinoglu A
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- Humans, Animals, Rats, Mitochondria metabolism, Models, Animal, Disease Models, Animal, Neurodegenerative Diseases metabolism, Parkinson Disease metabolism, Alzheimer Disease metabolism
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Background: Neurodegenerative diseases (NDDs), including Alzheimer's disease (AD) and Parkinson's disease (PD), are associated with metabolic abnormalities. Integrative analysis of human clinical data and animal studies have contributed to a better understanding of the molecular and cellular pathways involved in the progression of NDDs. Previously, we have reported that the combined metabolic activators (CMA), which include the precursors of nicotinamide adenine dinucleotide and glutathione can be utilized to alleviate metabolic disorders by activating mitochondrial metabolism., Methods: We first analysed the brain transcriptomics data from AD patients and controls using a brain-specific genome-scale metabolic model (GEM). Then, we investigated the effect of CMA administration in animal models of AD and PD. We evaluated pathological and immunohistochemical findings of brain and liver tissues. Moreover, PD rats were tested for locomotor activity and apomorphine-induced rotation., Findings: Analysis of transcriptomics data with GEM revealed that mitochondrial dysfunction is involved in the underlying molecular pathways of AD. In animal models of AD and PD, we showed significant damage in the high-fat diet groups' brain and liver tissues compared to the chow diet. The histological analyses revealed that hyperemia, degeneration and necrosis in neurons were improved by CMA administration in both AD and PD animal models. These findings were supported by immunohistochemical evidence of decreased immunoreactivity in neurons. In parallel to the improvement in the brain, we also observed dramatic metabolic improvement in the liver tissue. CMA administration also showed a beneficial effect on behavioural functions in PD rats., Interpretation: Overall, we showed that CMA administration significantly improved behavioural scores in parallel with the neurohistological outcomes in the AD and PD animal models and is a promising treatment for improving the metabolic parameters and brain functions in NDDs., Competing Interests: Declaration of competing interest AM, JB and MU are the founder and shareholders of ScandiBio Therapeutics. The other authors declare no competing interests., (Copyright © 2022 The Authors. Published by Elsevier Inc. All rights reserved.)
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- 2023
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19. Combined metabolic activators improve cognitive functions in Alzheimer's disease patients: a randomised, double-blinded, placebo-controlled phase-II trial.
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Yulug B, Altay O, Li X, Hanoglu L, Cankaya S, Lam S, Velioglu HA, Yang H, Coskun E, Idil E, Nogaylar R, Ozsimsek A, Bayram C, Bolat I, Oner S, Tozlu OO, Arslan ME, Hacimuftuoglu A, Yildirim S, Arif M, Shoaie S, Zhang C, Nielsen J, Turkez H, Borén J, Uhlén M, and Mardinoglu A
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- Animals, Rats, Treatment Outcome, Cognition, Double-Blind Method, Alzheimer Disease metabolism
- Abstract
Background: Alzheimer's disease (AD) is associated with metabolic abnormalities linked to critical elements of neurodegeneration. We recently administered combined metabolic activators (CMA) to the AD rat model and observed that CMA improves the AD-associated histological parameters in the animals. CMA promotes mitochondrial fatty acid uptake from the cytosol, facilitates fatty acid oxidation in the mitochondria, and alleviates oxidative stress., Methods: Here, we designed a randomised, double-blinded, placebo-controlled phase-II clinical trial and studied the effect of CMA administration on the global metabolism of AD patients. One-dose CMA included 12.35 g L-serine (61.75%), 1 g nicotinamide riboside (5%), 2.55 g N-acetyl-L-cysteine (12.75%), and 3.73 g L-carnitine tartrate (18.65%). AD patients received one dose of CMA or placebo daily during the first 28 days and twice daily between day 28 and day 84. The primary endpoint was the difference in the cognitive function and daily living activity scores between the placebo and the treatment arms. The secondary aim of this study was to evaluate the safety and tolerability of CMA. A comprehensive plasma metabolome and proteome analysis was also performed to evaluate the efficacy of the CMA in AD patients., Results: We showed a significant decrease of AD Assessment Scale-cognitive subscale (ADAS-Cog) score on day 84 vs day 0 (P = 0.00001, 29% improvement) in the CMA group. Moreover, there was a significant decline (P = 0.0073) in ADAS-Cog scores (improvement of cognitive functions) in the CMA compared to the placebo group in patients with higher ADAS-Cog scores. Improved cognitive functions in AD patients were supported by the relevant alterations in the hippocampal volumes and cortical thickness based on imaging analysis. Moreover, the plasma levels of proteins and metabolites associated with NAD + and glutathione metabolism were significantly improved after CMA treatment., Conclusion: Our results indicate that treatment of AD patients with CMA can lead to enhanced cognitive functions and improved clinical parameters associated with phenomics, metabolomics, proteomics and imaging analysis. Trial registration ClinicalTrials.gov NCT04044131 Registered 17 July 2019, https://clinicaltrials.gov/ct2/show/NCT04044131., (© 2023. The Author(s).)
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- 2023
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20. Neuroimaging-Guided Transcranial Magnetic and Direct Current Stimulation in MCI: Toward an Individual, Effective and Disease-Modifying Treatment.
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Hanoglu L, Velioglu HA, Hanoglu T, and Yulug B
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- Humans, Electroencephalography, Neuroimaging, Magnetic Phenomena, Transcranial Magnetic Stimulation methods, Cognitive Dysfunction therapy
- Abstract
The therapeutic approaches currently applied in Alzheimer's disease (AD) and similar neurodegenerative diseases are essentially based on pharmacological strategies. However, despite intensive research, the effectiveness of these treatments is limited to transient symptomatic effects, and they are still far from exhibiting a true therapeutic effect capable of altering prognosis. The lack of success of such pharmacotherapy-based protocols may be derived from the cases in the majority of trials being too advanced to benefit significantly in therapeutic terms at the clinical level. For neurodegenerative diseases, mild cognitive impairment (MCI) may be an early stage of the disease continuum, including Alzheimer's. Noninvasive brain stimulation (NIBS) techniques have been developed to modulate plasticity in the human cortex in the last few decades. NIBS techniques have made it possible to obtain unique findings concerning brain functions, and design novel approaches to treat various neurological and psychiatric conditions. In addition, its synaptic and cellular neurobiological effects, NIBS is an attractive treatment option in the early phases of neurodegenerative diseases, such as MCI, with its beneficial modifying effects on cellular neuroplasticity. However, there is still insufficient evidence about the potential positive clinical effects of NIBS on MCI. Furthermore, the huge variability of the clinical effects of NIBS limits its use. In this article, we reviewed the combined approach of NIBS with various neuroimaging and electrophysiological methods. Such methodologies may provide a new horizon to the path for personalized treatment, including a more individualized pathophysiology approach which might even define new specific targets for specific symptoms of neurodegenerations.
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- 2023
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21. Evaluating the Clinical Significance of Diazepam Binding Inhibitor in Alzheimer's Disease: A Comparison with Inflammatory, Oxidative, and Neurodegenerative Biomarkers.
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Gokce M, Velioglu HA, Bektay MY, and Guler EM
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- Humans, Diazepam Binding Inhibitor, Biomarkers, Oxidative Stress, Clinical Relevance, Alzheimer Disease diagnosis, Alzheimer Disease drug therapy
- Abstract
Introduction: Alzheimer's disease (AD) is one of the pathologies that the scientific world is still desperate for. The aim of this study was the investigation of diazepam binding inhibitor (DBI) as a prognostic factor for AD prognosis., Methods: A total of 120 participants were divided into 3 groups. Forty new diagnosed Alzheimer patients (NDG) who have been diagnosed but have not started AD treatment, 40 patients who diagnosed 5 years ago (D5YG), and 40 healthy control groups (CG) were included in the study. Levels of DBI, oxidative stress, inflammatory, and neurodegenerative biomarkers were compared between 3 groups., Results: Plasma levels of DBI, oligomeric Aβ, total tau, glial fibrillary acidic protein, α-synuclein, interleukin (IL) 1β, IL6, tumor necrosis factor α, oxidative stress index, high-sensitive C-reactive protein, and DNA damage were found higher in D5YG and NDG as compared to CG (p < 0.001). On the contrary, plasma levels of total thiol, native thiol, vitamin D and vitamin B12 were lower in D5YG and NDG as compared to CG (p < 0.001)., Discussion: DBI may be a potential plasma biomarker and promising drug target for AD. It could help physicians make a comprehensive evaluation with cognitive and neurodegenerative tests., (© 2023 S. Karger AG, Basel.)
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- 2023
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22. Chemogenetic inhibition of MCH neurons does not alter memory performance in mice.
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Mutlu-Burnaz O, Yulug B, Oncul M, Celik E, Atasoy NS, Cankaya S, Hanoglu L, and Velioglu HA
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- Animals, Mice, Pituitary Hormones physiology, Sleep, REM, Melanins, Neurons physiology, Hypothalamic Hormones physiology
- Abstract
Memory storage in the brain is one of the most extensively studied subjects in neuroscience. However, due to the highly complex structure of the memory-related systems in the brain, the mystery remains unsolved. Consolidation is one of the most important parts of the memory process, and one that can be affected by numerous neurodegenerative diseases. Hypothalamic melanin-concentrating hormone (MCH) neuronal activity has been of particular interest to researchers in terms of the association between sleep, neurodegenerative diseases, and memory consolidation. We used Pmch-Cre animals to investigate the role of MCH neuronal activity in memory consolidation. In order to observe the differences in memory consolidation, we chemogenetically inhibited MCH neurons using the DREADD method and measured hippocampus-dependent memory performance with a novel object recognition test applicable to early memory impairment in Alzheimer's disease. Our results revealed no significant improvement or worsening with MCH inhibition, suggesting that the role of MCH should now be evaluated in a wider setting., Competing Interests: Conflict of interest statement None., (Copyright © 2022 The Authors. Published by Elsevier Masson SAS.. All rights reserved.)
- Published
- 2022
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23. Predicting the Effects of Repetitive Transcranial Magnetic Stimulation on Cognitive Functions in Patients With Alzheimer's Disease by Automated EEG Analysis.
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Kayasandik CB, Velioglu HA, and Hanoglu L
- Abstract
Alzheimer's disease (AD) is a progressive, neurodegenerative brain disorder that generally affects the elderly. Today, after the limited benefit of the pharmacological treatment strategies, numerous noninvasive brain stimulation techniques have been developed. Transcranial magnetic stimulation (TMS), based on electromagnetic stimulation, is one of the most widely used methods. The main problem in the use of TMS is the existence of large individual variability in the results. This causes a waste of money, time, and more importantly, a burden for delicate patients. Hence, it is a necessity to form an efficient and personalized TMS application protocol. In this paper, we performed a machine-learning analysis to see whether it is possible to predict the responses of patients with AD to TMS by analyzing their electroencephalography (EEG) signals. For that purpose, we analyzed both the EEG signals collected before and after the TMS application (EEG1 and EEG2, respectively). Through correlating EEG1 and repetitive transcranial magnetic stimulation (rTMS) outcomes, we tried to see whether it is possible to predict patients' responses before the treatment application. On the other hand, by EEG2 analysis, we investigated TMS impacts on EEG, more importantly if this impact is correlated with patients' response to the treatment. We used the support vector machine (SVM) classifier due to its multiple advantages for the current task with feature selection processes by stepwise linear discriminant analysis (SWLDA) and SVM. However, to justify our numerical analysis framework, we examined and compared the performances of different feature selection and classification techniques. Since we have a limited sample number, we used the leave-one-out method for the validation with the Monte Carlo technique to eliminate bias by a small sample size. In the conclusion, we observed that the correlation between rTMS outcomes and EEG2 is stronger than EEG1, since we observed, respectively, 93 and 79% of accuracies during our data analysis. Besides the informative features of EEG2 are focused on theta band, it indicates that TMS is characterizing the theta band signals in patients with AD in direct relation to patients' response to rTMS. This shows that it is more possible to determine patients' benefit from the TMS at the early stages of the treatment, which would increase the efficiency of rTMS applications in patients with Alzheimer's disease., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Kayasandik, Velioglu and Hanoglu.)
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- 2022
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24. Clinical evaluation and resting state fMRI analysis of virtual reality based training in Parkinson's disease through a randomized controlled trial.
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Hajebrahimi F, Velioglu HA, Bayraktaroglu Z, Helvaci Yilmaz N, and Hanoglu L
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- Exercise Therapy methods, Humans, Magnetic Resonance Imaging, Neuropsychological Tests, Parkinson Disease diagnostic imaging, Parkinson Disease therapy, Virtual Reality
- Abstract
There are few studies investigating the short-term effects of Virtual Reality based Exergaming (EG) on motor and cognition simultaneously and pursue the brain functional activity changes after these interventions in patients with Parkinson's Disease (PD). The purpose of this study was to investigate the synergistic therapeutic effects of Virtual Reality based EG on motor and cognitive symptoms in PD and its possible effects on neuroplasticity. Eligible patients with the diagnosis of PD were randomly assigned to one of the two study groups: (1) an experimental EG group, (2) an active control Exercise Therapy (ET) group. All patients participated in a 4-week exercise program consisting of 12 treatment sessions. Every session lasted 60 min. Participants underwent a motor evaluation, extensive neuropsychological assessment battery and rs-fMRI before and after the interventions. Thirty patients fulfilled the inclusion criteria and were randomly assigned to the EG and ET groups. After the dropouts, 23 patients completed the assessments and interventions (11 in EG, 13 in ET). Within group analysis showed significant improvements in both groups. Between group comparisons considering the interaction of group × time effect, showed superiority of EG in terms of general cognition, delayed visual recall memory and Boston Naming Test. These results were consistent in the within-group and between-group analysis. Finally, rs-fMRI analysis showed increased activity in the precuneus region in the time × group interaction in the favor of EG group. EG can be an effective alternative in terms of motor and cognitive outcomes in patients with PD. Compared to ET, EG may affect brain functional connectivity and can have beneficial effects on patients' cognitive functions and motor symptoms. Whenever possible, using EG and ET in combination, may have the better effects on patients daily living and patients can benefit from the advantages of both interventions., (© 2022. The Author(s).)
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- 2022
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25. Therapeutic Role of Repetitive Transcranial Magnetic Stimulation in Alzheimer's and Parkinson's Disease: Electroencephalography Microstate Correlates.
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Hanoglu L, Toplutas E, Saricaoglu M, Velioglu HA, Yildiz S, and Yulug B
- Abstract
Introduction: The microstate analysis is a method to convert the electrical potentials on the multi-channel electrode array to topographical electroencephalography (EEG) data. Repetitive transcranial magnetic stimulation (rTMS) is a non-invasive method that can modulate brain networks. This study explores the pathophysiological changes through microstate analysis in two different neurodegenerative diseases, Alzheimer's (AD) and Parkinson's disease (PD), characterized by motor and cognitive symptoms and analysis the effect of rTMS on the impaired cognitive and motor functions., Materials and Methods: We included 18 AD, 8 PD patients, and 13 age-matched controls. For both groups, we applied 5 Hz rTMS on the left pre-SMA in PD patients while 20 Hz rTMS on the left lateral parietal region in AD patients. Each patient was re-evaluated 1 week after the end of the sessions, which included a detailed clinical evaluation and measurement of EEG microstates., Results: At the baseline, the common findings between our AD and PD patients were altered microstate (MS) B, MS D durations and transition frequencies between MS A-MS B, MS C-MS D while global explained variance (GEV) ratio and the extent and frequency of occurrence of MS A, MS B, and MS D were separately altered in AD patients. Although no specific microstate parameter adequately differentiated between AD and PD patients, we observed significant changes in MS B and MS D parameters in PD patients. Further, we observed that Mini-Mental State Examination (MMSE) performances were associated with the transition frequencies between MS A-MS B and MS C-MS D and GEV ratio. After left parietal rTMS application, we have observed significantly increased visual memory recognition and clock drawing scores after left parietal rTMS application associated with improved microstate conditions prominent, especially in the mean duration of MS C in AD patients. Also, pre-SMA rTMS resulted in significant improvement in motor scores and frequency of transitions from MS D to MS C in PD patients., Conclusion: This study shows that PD and AD can cause different and similar microstate changes that can be modulated through rTMS, suggesting the role of MS parameters and rTMS as a possible combination in monitoring the treatment effect in neurodegenerative diseases., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Hanoglu, Toplutas, Saricaoglu, Velioglu, Yildiz and Yulug.)
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- 2022
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26. DLPF Targeted Repetitive Transcranial Magnetic Stimulation Improves Brain Glucose Metabolism Along with the Clinical and Electrophysiological Parameters in CBD Patients.
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Toprak G, Hanoglu L, Cakir T, Guntekin B, Velioglu HA, and Yulug B
- Subjects
- Brain pathology, Female, Glucose, Humans, Male, Transcranial Magnetic Stimulation methods, Corticobasal Degeneration, Neurodegenerative Diseases pathology
- Abstract
Background: Corticobasal Degeneration (CBD) is a rare neurological disease caused by the pathological accumulation of tau protein. The primary pathological features of CBD include progressive neurodegenerative processes resulting in remarkable frontoparietal and basal ganglia atrophy., Objective: Like in many other neurodegenerative disorders, there is still no effective disease-modifying drug therapy in CBD. Therefore, the development of new treatment methods is of great importance. In this study, we aimed to assess the stimulating effects of high-frequency DLPFC rTMS on the motor, cognitive and behavioral disturbances in four CBD patients., Methods: Four (three females, one male) CBD patients who had been diagnosed as CBD were enrolled in this study. Patients were evaluated before and after the rTMS procedure regarding the motor, neuropsychometric and behavioral tests. The results of statistical analysis of behavioral and neuropsychometric evaluation were assessed via SPSS 18.0 package program. Data are expressed as mean, standard deviation. Before and after values of the groups were compared with the Wilcoxon sign rank test, and p<0.05 was considered significant., Results: We have provided strong preliminary evidence that the improvement in clinical parameters was associated with the normalizations of the theta activity and glucose metabolism., Conclusion: Our current results are consistent with some previous trials showing a strong association between DLPFC targeted rTMS and electrophysiological normalizations in the left DLPFC., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.net.)
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- 2022
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27. Quantitative evaluation of brain volumes in drug-free major depressive disorder using MRI-Cloud method.
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Avnioglu S, Velioglu HA, Cankaya S, and Yulug B
- Subjects
- Adult, Anxiety epidemiology, Case-Control Studies, Depressive Disorder, Major epidemiology, Female, Humans, Magnetic Resonance Imaging methods, Male, Organ Size, Smoking adverse effects, Smoking epidemiology, Young Adult, Anxiety diagnostic imaging, Brain diagnostic imaging, Depressive Disorder, Major diagnostic imaging, Magnetic Resonance Imaging standards
- Abstract
Background: Quantitative analysis of the high-resolution T1-weighted images provides useful markers to measure anatomical changes during brain degeneration related to major depressive disorder (MDD). However, there are controversial findings regarding these volume alterations in MDD indicating even to increased volumes in some specific regions in MDD patients., Methods: This study is a case-controlled study including 23 depression patients and 15 healthy subject person and 20-38 years of age, who have been treated at the Neurology and Psychiatry Department here. We compared specific anatomic regions between drug-free MDD patients and control group through MRI-Cloud, which is a novel brain imaging method that enables to analyze multiple brain regions simultaneously., Results: We have found that frontal, temporal, and parietal hemispheric volumes and middle frontal gyrus, inferior frontal gyrus, superior parietal gyrus, cingulum-hippocampus, lateral fronto-orbital gyrus, superior temporal gyrus, superior temporal white matter, middle temporal gyrus subanatomic regions were significantly reduced bilaterally in MDD patients compared to the control group, while striatum, amygdala, putamen, and nucleus accumbens bilaterally increased in MDD group compared to the control group suggesting that besides the heterogeneity among studies, also comorbid factors such as anxiety and different personal traits could be responsible for these discrepant results., Conclusion: Our study gives a strong message that depression is associated with altered structural brain volumes, especially, in drug-free and first-episode MDD patients who present with similar duration and severity of depression while the role of demographic and comorbid risk factors should not be neglected., (Copyright © 2021 Wolters Kluwer Health, Inc. All rights reserved.)
- Published
- 2021
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28. Left lateral parietal rTMS improves cognition and modulates resting brain connectivity in patients with Alzheimer's disease: Possible role of BDNF and oxidative stress.
- Author
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Velioglu HA, Hanoglu L, Bayraktaroglu Z, Toprak G, Guler EM, Bektay MY, Mutlu-Burnaz O, and Yulug B
- Subjects
- Aged, Alzheimer Disease physiopathology, Brain physiopathology, Female, Functional Neuroimaging, Humans, Magnetic Resonance Imaging, Male, Middle Aged, Neural Pathways diagnostic imaging, Neural Pathways physiopathology, Sulfhydryl Compounds blood, Alzheimer Disease diagnostic imaging, Brain diagnostic imaging, Brain-Derived Neurotrophic Factor blood, Oxidative Stress, Parietal Lobe, Transcranial Magnetic Stimulation methods
- Abstract
Repetitive Transcranial Magnetic Stimulation (rTMS) is a non-invasive neuromodulation technique which is increasingly used for cognitive impairment in Alzheimer's Disease (AD). Although rTMS has been shown to modify Brain-Derived Neurotrophic Factor (BDNF) and oxidative stress levels in many neurological and psychiatric diseases, there is still no study evaluating the relationship between memory performance, BDNF, oxidative stress, and resting brain connectivity following rTMS in Alzheimer's patients. Furthermore, there are increasing clinical data showing that the stimulation of strategic brain regions may lead to more robust improvements in memory functions compared to conventional rTMS. In this study, we aimed to evaluate the possible disease-modifying effects of rTMS on the lateral parietal cortex in AD patients who have the highest connectivity with the hippocampus. To fill the mentioned research gaps, we have evaluated the relationships between resting-state Functional Magnetic Resonance Imaging (fMRI), cognitive scores, blood BDNF levels, and total oxidative/antioxidant status to explain the therapeutic and potential disease-modifying effects of rTMS which has been applied at 20 Hz frequencies for two weeks. Our results showed significantly increased visual recognition memory functions and clock drawing test scores which were associated with elevated peripheral BDNF levels, and decreased oxidant status after two weeks of left lateral parietal TMS stimulation. Clinically our findings suggest that the left parietal region targeted rTMS application leads to significant improvement in familiarity-based cognition associated with the network connections between the left parietal region and the hippocampus., (Copyright © 2021 Elsevier Inc. All rights reserved.)
- Published
- 2021
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29. Topological network mechanisms of clinical response to antidepressant treatment in drug-naive major depressive disorder.
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Uykur AB, Yıldız S, Velioglu HA, Ozsimsek A, Oktem EO, Bayraktaroglu Z, Ergun T, Lakadamyali H, Hanoglu L, Cankaya S, Saatçi Ö, and Yulug B
- Subjects
- Adult, Brain physiopathology, Citalopram therapeutic use, Cross-Sectional Studies, Duloxetine Hydrochloride pharmacology, Duloxetine Hydrochloride therapeutic use, Female, Humans, Image Interpretation, Computer-Assisted methods, Magnetic Resonance Imaging methods, Male, Nerve Net physiopathology, Antidepressive Agents therapeutic use, Brain drug effects, Depressive Disorder, Major drug therapy, Depressive Disorder, Major physiopathology, Nerve Net drug effects
- Abstract
Aim: There is rapidly increasing evidence that remission of MDD is associated with substantial changes in functional brain connectivity. These New data have provided a holistic view on the mechanism of antidepressants on multiple levels that goes beyond their conventional effects on neurotransmitters., Method: The study was approved by the Local Ethics Committee of Istanbul Medipol University (10840098-604.01.01-E.65129) and followed the Helsinki Declaration principles. In our study, we have evaluated the effect of six weeks of treatment with antidepressants (escitalopram and duloxetine), and tested the underlying brain functional connectivity through a Graph analysis approach in a well-defined first-episode, drug-naive, and non-comorbid population with MDD., Results: Beyond indicating that there was a significant correlation between the antidepressant response and topological characteristics of the brain, our results suggested that global rather than regional network alterations may be implicated in the antidepressant effect., Conclusion: Despite the small-sample size and non-controlled study design, our study provides important and relevant clinical data regarding the underlying mechanisms of the antidepressants on topological dynamics in the human brain., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier Ltd. All rights reserved.)
- Published
- 2021
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30. Paracetamol alters empathy scores in healthy and headache subjects: Functional MRI correlates.
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Cankaya S, Oktem EO, Saatci O, Velioglu HA, Uygur AB, Ozsimsek A, Hanoglu L, and Yulug B
- Subjects
- Adult, Brain physiopathology, Female, Humans, Magnetic Resonance Imaging, Male, Middle Aged, Pain Measurement, Tension-Type Headache, Acetaminophen pharmacology, Empathy, Headache physiopathology, Headache psychology
- Abstract
Introduction: Although previous evidence suggest that paracetamol decreases psychological reactivity in healthy subjects, there is still no confirmed correlation between the empathy scores and brain activity in healthy and headache patients after paracetamol treatment., Material and Methods: The study group included 16 patients with tension-type headache, and 12 healthy age-and sex-matched controls. After a detailed neurological examination Positive and Negative Affect Schedule (PANAS) and Empathy for Pain Scale (EPS) were applied to all subjects. Next, 1000 mg paracetamol tablet was administered orally, after administration of paracetamol, EPS were repeated, and fMRI was performed to all subjects., Results: We have revealed increased empathy scores in the headache group after the paracetamol treatment which were associated with significant alterations in brain regions which play a critical role in the processing of empathy., Discussion: The observed neuroimaging and clinical difference between healthy and headache subjects could be related to the fact that pain perception in healthy subjects might differ in some aspects from the mechanisms of empathy in headache-experienced patients., Conclusion: To the best of our knowledge, this is the first study that evaluated the paracetamol treatment and neural networks' correlation with pain empathy in healthy and headache individuals., (Copyright © 2020 Elsevier Ltd. All rights reserved.)
- Published
- 2020
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