Scopus İndeksli Yayınlar Koleksiyonu / Scopus Indexed Publications Collection
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Article Citation - WoS: 6Citation - Scopus: 72db: a Proteomics Database for Storage, Analysis, Presentation, and Retrieval of Information From Mass Spectrometric Experiments(Biomed Central Ltd, 2008) Allmer, Jens; Kuhlgert, Sebastian; Hippler, MichaelBackground: The amount of information stemming from proteomics experiments involving (multi dimensional) separation techniques, mass spectrometric analysis, and computational analysis is ever-increasing. Data from such an experimental workflow needs to be captured, related and analyzed. Biological experiments within this scope produce heterogenic data ranging from pictures of one or two-dimensional protein maps and spectra recorded by tandem mass spectrometry to text-based identifications made by algorithms which analyze these spectra. Additionally, peptide and corresponding protein information needs to be displayed. Results: In order to handle the large amount of data from computational processing of mass spectrometric experiments, automatic import scripts are available and the necessity for manual input to the database has been minimized. Information is in a generic format which abstracts from specific software tools typically used in such an experimental workflow. The software is therefore capable of storing and cross analysing results from many algorithms. A novel feature and a focus of this database is to facilitate protein identification by using peptides identified from mass spectrometry and link this information directly to respective protein maps. Additionally, our application employs spectral counting for quantitative presentation of the data. All information can be linked to hot spots on images to place the results into an experimental context. A summary of identified proteins, containing all relevant information per hot spot, is automatically generated, usually upon either a change in the underlying protein models or due to newly imported identifications. The supporting information for this report can be accessed in multiple ways using the user interface provided by the application. Conclusion: We present a proteomics database which aims to greatly reduce evaluation time of results from mass spectrometric experiments and enhance result quality by allowing consistent data handling. Import functionality, automatic protein detection, and summary creation act together to facilitate data analysis. In addition, supporting information for these findings is readily accessible via the graphical user interface provided. The database schema and the implementation, which can easily be installed on virtually any server, can be downloaded in the form of a compressed file from our project webpage.Article Citation - Scopus: 1Ablation of Atrioventricular Nodal Reentrant Tachycardia With Focal Cryoablation, Compared With Radiofrequency Ablation: Single-Center Experience(2024) Topaloğlu, C.; Fici, F.; Borne, P.V.; Taşkin, U.; Dogdus, M.; Saygi, S.; Tengiz, I.BACKGROUND: The ablation of atrioventricular nodal reentrant tachycardia (AVNRT) with cryoablation is an alternative to radiofrequency (RF) ablation in patients due to the low risk of total atrioventricular block. An increase in early-late recurrences after cryoablation is reported as an important disadvantage. OBJECTIVES: In this study, we aimed to compare the acute procedural success and the long-term recurrence rates of patients, with AVNRT who underwent methods. METHODS: 73 patients with AVNRT were included in the study: 32 with cryoablation and 41 with RF ablation. There was no statistically significant difference between acute procedural success in methods. The ablation procedure was performed by an operator experienced in arrhythmology. The choice of RF or cryoablation was made in the electrophysiology laboratory based on the material already available during the procedure. After the procedure, the patients were evaluated every 3 months for 2 years in polyclinic control. The significance level adopted in the statistical analysis was 5%. RESULTS: The 2 groups of patients were homogeneous.Article Citation - WoS: 9Citation - Scopus: 8Abnormal Cross Frequency Coupling of Brain Electroencephalographic Oscillations Related To Visual Oddball Task in Parkinson's Disease With Mild Cognitive Impairment(Sage Publications Inc, 2023) Bayraktaroglu, Zubeyir; Akturk, Tuba; Yener, Görsev; de Graaf, Tom A.; Hanoglu, Lutfu; Yildirim, Ebru; Gunduz, Duygu HunerliParkinson's disease (PD) is a movement disorder caused by degeneration in dopaminergic neurons. During the disease course, most of PD patients develop mild cognitive impairment (PDMCI) and dementia, especially affecting frontal executive functions. In this study, we tested the hypothesis that PDMCI patients may be characterized by abnormal neurophysiological oscillatory mechanisms coupling frontal and posterior cortical areas during cognitive information processing. To test this hypothesis, event-related EEG oscillations (EROs) during counting visual target (rare) stimuli in an oddball task were recorded in healthy controls (HC; N = 51), cognitively unimpaired PD patients (N = 48), and PDMCI patients (N = 53). Hilbert transform served to estimate instantaneous phase and amplitude of EROs from delta to gamma frequency bands, while modulation index computed ERO phase-amplitude coupling (PAC) at electrode pairs. As compared to the HC and PD groups, the PDMCI group was characterized by (1) more posterior topography of the delta-theta PAC and (2) reversed delta-low frequency alpha PAC direction, ie, posterior-to-anterior rather than anterior-to-posterior. These results suggest that during cognitive demands, PDMCI patients are characterized by abnormal neurophysiological oscillatory mechanisms mainly led by delta frequencies underpinning functional connectivity from frontal to parietal cortical areas.Article Citation - WoS: 1Citation - Scopus: 1Abstinence-Related Motivational Engagement Scale: Validity and Reliability in Turkish People(Bilimsel Tip Publishing House, 2018) Yavan, Tulay; Gulesen, Asli; Bebis, HaticeOBJECTIVES: This research aimed to conduct a validity and reliability study of the Turkish version of the abstinence-related motivational engagement (ARME) scale. MATERIALS AND METHODS: This study included 122 people and was administered in a smoking cessation clinic. The sociodemographic-smoking status characteristics questionnaire and the ARME scale were used for data collection. A psycholinguistic language adaptation was performed. In the validity, analyses, content, construct, and criterion-related validities were used. For content validity, expert evaluation was performed. For construct validity, principal component analyses (exploratory factor analyses) were performed. Orthogonal (Varimax) rotation was used to explore multiple factors. The Kaiser-Meyer-Olkin test was used to assess the adequacy of the sample size. For criterion-related validity, we compared the ARME scale points of people who were abstinent and had relapse for smoking at the end of the sixth month. In the reliability analysis, standard deviation (SD) and item analysis, internal consistency, and test-retest methods were used. RESULTS: The four factors explain 58% of the total variance. Items have factor loading between 0.409 and 0.805. When the factor structure of the scale was assessed, the items in each factor group have a factor load of at least 0.40. Due to one-dimensional use of the original scale, it has been decided to maintain this scale in its original form. The ARME scale points of people who quit smoking were statistically higher than the points of people who had relapse at the end of the sixth month. Cronbach's alpha coefficients were between 0.846 and 0.763. Significant and positive correlation was found between the test-retest scale scores. CONCLUSION: The Turkish adaptation of the ARME scale, which was developed for adults who quitted smoking, is an adequately valid and reliable measurement instrument. It is considered that the scale might be used reliably in different cultures as well.Article Citation - WoS: 5Citation - Scopus: 6Adaptation of Quality of Life Measure for Limb Lymphedema-Arm in Turkish Women With Breast Cancer-Related Lymphedema(Lippincott Williams & Wilkins, 2021) Karayurt, Ozgul; Deveci, Zeynep; Eyigor, Sibel; Inbat, Menekse OzgurBackground Quality-of-life measures are needed for clinicians and researchers to identify quality of women's life with breast cancer-related lymphedema (BCRL). Objective To adapt Quality of Life Measure for Limb Lymphedema-Arm into Turkish (TR) and to test its validity and reliability. Methods This is a methodological and cross-sectional study and was conducted in the lymphedema outpatient clinic of a university hospital. The study included 109 women with BCRL. After linguistic validity of the scale was achieved, confirmatory factor analyses and known group validity were used to test its construct validity. Reliability of the scale was tested with Cronbach's alpha, item-total correlations, and Spearman-Brown coefficient. Results After linguistic validity was achieved, opinions requested from 5 experts specializing in lymphedema showed that item and content validity indexes of the scale were 1. Fit indexes of confirmatory factor analysis were as follows: chi(2)/df = 1.86, root mean square error of approximation = 0.089, standardized root mean square residual = 0.09, and comparative fit index = 0.81. Known group validity analysis showed a significant difference in the mean scores for the subscales of Quality of Life Measure for Limb Lymphedema-Arm-TR, symptom, function, and body image/appearance in terms of lymphedema stages (P < .05). The internal reliability coefficients for the subscales ranged from 0.78 and 0.86. The item-total correlation coefficients ranged between 0.36 and 0.73. Conclusion Quality of Life Measure for Limb Lymphedema-Arm-TR was found to be valid and reliable in the TR population. It could be used in research to evaluate the quality of life in patients with BCRL. Implications for Practice The scale can be used to evaluate effectiveness of nursing interventions directed toward patients developing breast cancer-related lymphedema in clinical settings and studies.Article Citation - WoS: 2Citation - Scopus: 2Adjuvant Action of Needle-Shaped Bc Microfibrils(Springer, 2023) Sür, Özge; Gül, Aytul; Hames, Elif EsinBacterial cellulose (BC) is an unbranched biopolymer produced by microorganisms and composed of glucopyranose units linked by beta-1,4 bonds. This study investigates the adjuvant action of needle-shaped BC microfibrils (BCmFs) in vitro using bovine serum albumin (BSA) as a model antigen. BC produced by the static culture of Komagataibacter xylinus was then microparticled (1-5 mu m) by acid hydrolysis and characterized using Dynamic Light Scattering and Scanning Electron Microscopy. Subsequently, Attenuated Total Reflectance-Fourier-Transform Infrared Spectroscopy, cytotoxicity, TNF-alpha (tumour necrosis factor-alpha) and IL-6 (interleukin-6) cytokine secretion, and cellular uptake of the BCmFs-BSA conjugate on the human monocyte cell line (U937) differentiated into macrophages were performed. The microfibrils were determined to be 1-5 mu m in size, needle-shaped, with a zeta potential of - 32 mV. Their conjugation with the model antigen, BSA, was demonstrated by FTIR analysis. In the cytotoxicity assay, BCmFs-BSA in macrophage cells showed high viability (over 70%). Although the highest TNF-alpha cytokine level (113 pg/ml) was obtained with BCmFs-BSA (Bovine serum albumin) conjugate (500 mu g/ml) and was statistically significant (p = 0.0001) compared to the positive control group (BSA-aluminium hydroxide), IL-6 cytokine levels were not statistically different from those in the control group as desired. It has been shown in macrophage-differentiated U937 cells that microbially synthesized BC in the form of needle-shaped microfibrils (BCmFs) has a high cellular uptake capacity and increases the immunogenicity of the antigen. These results demonstrate for the first time that BCmFs have the potential to serve as a vaccine adjuvant.Article Citation - WoS: 2Citation - Scopus: 1Adjuvant Effects of Chemotherapeutics and Metformin on Mfe-319 Endometrial Carcinoma Cell Line(Editura Acad Romane, 2020) Aydemir, Isil; Uluer, Elgin Turkoz; Korkmaz, Oya; Tuglu, Mehmet Ibrahim; Inan, SevincWe aimed to investigate the cytotoxicity of Metformin, Cisplatin, and Paclitaxel on MFE-319 endometrial carcinoma cell line using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) and immunocytochemistry assays. Half maximal inhibitory concentration (IC50) doses of three drugs alone and in the dual combinations were applied to the cells. Immunocytochemical method was performed for the cell survival and for phosphatidylinositol 3-kinase (PI3K), phosphorylated extracellular regulated kinases (pErk)-1/2, Akt-1, phosphorylated Akt (pAkt)-1/2/3 cell growth markers and angiogenic vascular endothelial growth factor (VEGF). Immunoreactivities were evaluated using H-score and analyzed using the one-way analysis of variance (ANOVA) test for statistics. It was found that these drugs caused a decrease in the immunoreactivities of these markers. Particularly, dual combination of Paclitaxel and Cisplatin decreased the immunoreactivities of PI3K, pErk-1/2, Akt-1, and pAkt-1/2/3. Cisplatin and Paclitaxel were more effective than Metformin; on the other hand, Metformin has been shown to enhance the efficacy of these two drugs. In vitro or in vivo further studies are needed to investigate the efficacy of these three drugs via PI3K/Akt signal pathway.Article Citation - WoS: 2Citation - Scopus: 2Adrenomedullin Has No Effect on Segmental Bone Defect Healing but Increases Bone Mineral Density in Rat Model(AVES, 2023) Kaymakoğlu, Mehmet; Ciftci, E.; Korkusuz, P.; Ozdemir, E.; Erden, M.E.; Turhan, E.Objective: This study aimed to investigate the effect of adrenomedullin on the healing of the segmental bone defect in a rat model. Methods: Thirty-six Wistar rats were randomly divided into 6 groups based on follow-up periods and administered a dose of adreno-medullin hormone. In each group, bilaterally, a 2-mm bone defect was created at the diaphysis of the radius. Sodium chloride solution was administered to sham groups 3 times a week for 4 and 8 weeks intraperitoneally. Adrenomedullin was administered to the study groups 3 times a week: 15 μg—4 weeks, 15 μg—8 weeks, 30 μg—4 weeks, and 30 μg—8 weeks, respectively. After euthanasia, the segmental defects were evaluated by histomorphometric [new bone area (NBA)] and microtomographic [bone volume (BV), bone surface (BS), and bone mineral density (BMD)] analyses. Results: Although the 4-and 8-week 15 μg administered study groups had higher NBA values than the other study and control groups, the histomorphometric analysis did not reveal any statistical difference between the control and study groups regarding NBA (P >.05). In microtomographic analysis, BV was higher in the 15 μg 4-week group than 30 μg 4-week group (296.9 vs. 208.5, P =.003), and BS was lower in the 30 μg 4-week group than in the 4-week control group (695.5 vs. 1334.7, P =.005), but overall, no significant difference was found between the control and study groups (P >.05). Despite these minor differences in histomorphometric and microtomographic criteria indicating new bone formation, the BMD values of the 15 μg 8-week study group showed a significant increase compared with the control group (P =.001, respectively). Conclusion: Adrenomedullin positively affected BMD at 15 μg, but this study could not show healing in the segmental defect site at different dose regimens. Further studies are needed to assess its effects on bone tissue trauma. © 2023, AVES. All rights reserved.Article Citation - WoS: 7Citation - Scopus: 9Adults' Visual Cue Preferences and Wayfinding Abilities in Healthcare Centers(Sage Publications Inc, 2023) Asli, Afsaneh Alizadeh; Moshfeghifar, Samaneh; Mousighichi, Pouya; Samimi, Paniz MousaviObjectives: Physical and visual elements that help people find their way around an environment are called visual cues (VCs). The current study aims to evaluate adults' wayfinding abilities (navigation, orientation, spatial anxiety, and distance estimation) and VC (navigational color coding) preferences in terms of color and position; additionally, investigates their differences in adults' life span phases (young adults, early middle-aged adults, and late middle-aged adults). Background: Wayfinding in complex environments such as healthcare centers has been challenging for most people. Although VCs are being used increasingly to facilitate wayfinding, considering people's preferences regarding VCs, especially navigational color coding, are neglected. Methods: Obtained data from a survey of 375 healthcare center visitors with textual and photo questionnaires were analyzed by descriptive statics and one-way analysis of variance. Results: Young adults preferred VCs with mixed colors and positioned in the middle of the floor, early middle-aged adults preferred warm color VCs in the middle of the wall, and late middle-aged adults preferred warm color VCs at the bottom of the wall. Additionally, the results demonstrated that with aging, navigation and distance estimation abilities deteriorate, and spatial anxiety increases. Conclusions: The outcomes of the present study increase our knowledge regarding the impact of adults' life span phases on their wayfinding abilities and VC preferences and offer suggestions for architects and healthcare center stakeholders to provide environments that improve adults' wayfinding.Article Citation - WoS: 4Citation - Scopus: 5Advanced Nurse-Patient Communication System(Springer, 2012) Unluturk, Mehmet S.Effective communication is the most important part of any healthcare organization. For many years, hospital nurse call solutions had been stand-alone systems with occasional integration to pocket paging for outputting patient call alerts to mobile staff. In the late 1990's, technology enabled in-building wireless phones to supplement or replace paging systems as a means of not only sending alerts, but also enabling voice communication between mobile staff and patients. Today's nurse call market requires integration of additional information from location and ADT (admit, discharge, transfer) systems into what have traditionally been nurse call applications. This system information is required not only at the nursing station, pagers, and phones, but also at PC's placed on each patient care floor in hallways, nurse stations, and offices, and at areas away from the patients, including administrator and clinical engineering offices. It is crucial that nurses have the latest patient information in their hand wherever they go in the hospital. In this paper, MatchMaker.NET has been developed to integrate all these technologies into the hospital's LAN to improve nurse-patient communication.Review Citation - WoS: 10Citation - Scopus: 9Advancements in Platinum Chemotherapy for Metastatic Castration-Resistant Prostate Cancer: Insights and Perspectives(ELSEVIER SCI LTD, 2024) Akkuş, Erman; Arslan, Çağatay; Ürün, YükselDespite improvements in survival, metastatic castration-resistant prostate cancer (mCRPC) remains a significant clinical challenge. While taxanes, new hormonal agents, radiopharmaceuticals, and PARP inhibitors offer valuable treatment options, this review explores the potential of platinum chemotherapies (carboplatin, cisplatin, and oxaliplatin) as alternative choices. Existing research demonstrates promising preliminary results for platinum-based therapies in mCRPC showing PSA response rates (7.7-95 %) and improved overall survival (8-26.6 months). However, chemotherapy-related cytopenias are a frequent side effect. Further research is underway to evaluate the efficacy of platinum regimens against specific mCRPC histopathological variants, particularly aggressive subtypes where the carboplatin and cabazitaxel combination is already recommended. The unique DNA-targeting action of platinum therapy holds promise for patients with deficient DNA repair (dDDR), especially those with BRCA mutations. This potential is supported by both preclinical and ongoing clinical research. Given the limited success of immunotherapy in mCRPC, researchers are exploring the potential for platinum therapies to enhance its efficacy. Additionally, trials are investigating the synergy of combining platinum therapy with both immunotherapy and PARP inhibitors. Further exploration into the effectiveness of platinum therapies in specific mCRPC subpopulations, particularly those with dDDR, is crucial for optimizing their future use. In conclusion, this review highlights the promising potential of platinum-based chemotherapy as a valuable treatment option for mCRPC. While current evidence is encouraging, ongoing research is essential to further optimize its efficacy, identify optimal combinations with other therapies, and better understand its impact on specific mCRPC subpopulations.Article Citation - WoS: 94Citation - Scopus: 103Affective Interpersonal Touch in Close Relationships: a Cross-Cultural Perspective(Sage Publications Inc, 2021) Sorokowska, Agnieszka; Saluja, Supreet; Sorokowski, Piotr; Frackowiak, Tomasz; Karwowski, Maciej; Aavik, Toivo; Akello, Grace; Can, SedaInterpersonal touch behavior differs across cultures, yet no study to date has systematically tested for cultural variation in affective touch, nor examined the factors that might account for this variability. Here, over 14,000 individuals from 45 countries were asked whether they embraced, stroked, kissed, or hugged their partner, friends, and youngest child during the week preceding the study. We then examined a range of hypothesized individual-level factors (sex, age, parasitic history, conservatism, religiosity, and preferred interpersonal distance) and cultural-level factors (regional temperature, parasite stress, regional conservatism, collectivism, and religiosity) in predicting these affective-touching behaviors. Our results indicate that affective touch was most prevalent in relationships with partners and children, and its diversity was relatively higher in warmer, less conservative, and religious countries, and among younger, female, and liberal people. This research allows for a broad and integrated view of the bases of cross-cultural variability in affective touch.Article Citation - WoS: 2Citation - Scopus: 2Age-Related Aspects of Sex Differences in Event-Related Brain Oscillatory Responses: a Turkish Study(Mdpi, 2024) Yener, Görsev; Kıyı, İlayda; Düzenli-Öztürk, Seren; Yerlikaya, DenizEarlier research has suggested gender differences in event-related potentials/oscillations (ERPs/EROs). Yet, the alteration in event-related oscillations (EROs) in the delta and theta frequency bands have not been explored between genders across the three age groups of adulthood, i.e., 18-50, 51-65, and >65 years. Data from 155 healthy elderly participants who underwent a neurological examination, comprehensive neuropsychological assessment (including attention, memory, executive function, language, and visuospatial skills), and magnetic resonance imaging (MRI) from past studies were used. The delta and theta ERO powers across the age groups and between genders were compared and correlational analyses among the ERO power, age, and neuropsychological tests were performed. The results indicated that females displayed higher theta ERO responses than males in the frontal, central, and parietal regions but not in the occipital location between 18 and 50 years of adulthood. The declining theta power of EROs in women reached that of men after the age of 50 while the theta ERO power was more stable across the age groups in men. Our results imply that the cohorts must be recruited at specified age ranges across genders, and clinical trials using neurophysiological biomarkers as an intervention endpoint should take gender into account in the future.Article Citation - WoS: 2Citation - Scopus: 2Aging Attenuated Theta Response During Multistable Perception(Wiley, 2023) Küçük, Kurtulus Mert; Mathes, Birgit; Schmiedt-Fehr, Christina; Başar Eroğlu, CananMultistable stimuli are physically unchanging, but elicit spontaneous perceptual reversals between multiple internally generated perceptual alternatives. Perceptual reversal rates seem to decrease in older adults; however, there is no literature on the electrophysiological correlates of this performance decrease. Here, we aimed to identify age-related changes in theta activity that relate to decreased reversal rates of older adults. Electroencephalography (EEG) of young (n = 15) and older adults (n = 15) was recorded during presentation of stroboscopic alternative motion (SAM) and a control stimulus. Time-frequency amplitudes were extracted in 4-8 Hz via Morlet wavelet convolution. Older adults had lower SAM reversals as well as decreased accuracy, increased reaction time (RT) and increased RT variability in the control task. In older adults, reversal-related frontal theta response was diminished, yet parietal theta was intact. In the parietal area, the relationship between theta response and reversal rates was robust, but in the frontal area, was dependent on age-related variance. Result indicated that, in older adults, top-down facilitation of perceptual reversals was impaired. This appears to result in a predominantly bottom-up resolution of perceptual multistability. Age-related degradation of sensory areas in this bottom-up-driven resolution process might have slowed reversals. This study presents the first electrophysiological correlates of age-related impairment in multistable perceptual integration.Article Citation - WoS: 6Citation - Scopus: 6Agreement Between Tele-Assessment and Face-To Assessment of 30-S Sit-To Test in Patients With Type 2 Diabetes Mellitus(Springer London Ltd, 2023) Aktan, Ridvan; Yilmaz, Hayriye; Demir, Ismail; Ozalevli, SevgiBackground The globalization of healthcare systems, and the aim to lower healthcare costs have all contributed to the growth of telehealth technology in recent years. However, before these systems are put into use, their efficacy should be verified. To the best of our knowledge, this is the first study focusing on the evaluation of functional exercise capacity using the 30-s sit-to-stand (30-s STS) test as a tele-assessment method in patients with type 2 diabetes mellitus (T2DM). Aims The purpose of the study is to investigate the level of agreement between tele-assessment and face-to-face assessment of 30-s STS test in patients with T2DM. Methods Fifty participants performed two times 30-s STS tests separated by 1 h: a face-to-face and an Internet-connected video call examination (tele-assessment). Two physiotherapists conduct these evaluations; each was blinded to the other. The order of the evaluations was designated at random for each participant and physiotherapist. Results There was a good level of agreement between tele-assessment and face-to-face assessment of the 30-s STS test (mean differences = 0.20 +/- 0.88, limits of agreement =1.93 to - 1.53). Excellent interrater reliability was found for scores of the 30-s STS test [ICC = 0.93 (95% CI: 0.88; 0.96)]. In addition, all before and after test parameters show that there was a very good interrater reliability (rho >= 0.75). Conclusions This study shows a good level of agreement between tele-assessment and face-to-face assessment of the 30-s STS test. Our study's findings indicate that tele-assessment is a potential application to determine the level of physical capacity remotely in patients with T2DM.Article Citation - WoS: 36Citation - Scopus: 39Alteration of Mirnas in Small Neuron-Derived Extracellular Vesicles of Alzheimer's Disease Patients and the Effect of Extracellular Vesicles on Microglial Immune Responses(Springernature, 2022) Durur, Devrim Yagmur; Tastan, Bora; Tufekci, Kemal Ugur; Olcum, Melis; Uzuner, Hamdiye; Karakulah, Gokhan; Yener, GörsevAlzheimer's disease (AD) is one of the most severe neurodegenerative diseases observed in the elderly population. Although the hallmarks of AD have been identified, the methods for its definitive diagnosis and treatment are still lacking. Extracellular vesicles (EVs) have become a promising source for biomarkers since the identification of their content. EVs are released from multiple cell types and, when released from neurons, they pass from the brain to the blood with their cargo molecules. Hence, neuron-specific EV-resident microRNAs (miRNAs) are promising biomarkers for diagnosis of AD. This study aimed to identify altered miRNA content in small neuron-derived extracellular vesicles (sNDEVs) isolated from AD patients and healthy individuals. Furthermore, we examined the role of sNDEV-resident miRNAs in neuron-glia cellular interaction to understand their role in AD propagation. We identified 10 differentially expressed miRNAs in the sNDEVs of patients via next-generation sequencing and validated the most dysregulated miRNA, let-7e, with qRT-PCR. Let-7e was significantly increased in the sNDEVs of AD patients compared with those of healthy controls in a larger cohort. First, we evaluated the diagnostic utility of let-7e via ROC curve analysis, which revealed an AUC value of 0.9214. We found that IL-6 gene expression was increased in human microglia after treatment with sNDEVs of AD patients with a high amount of let-7e. Our study suggests that sNDEV-resident let-7e is a potential biomarker for AD diagnosis, and that AD patient-derived sNDEVs induce a neuroinflammatory response in microglia.Article Citation - WoS: 25Citation - Scopus: 29Alterations in Levels of 8-Oxo '-deoxyguanosine and 8-Oxoguanine Dna Glycosylase 1 During a Current Episode and After Remission in Unipolar and Bipolar Depression(Pergamon-Elsevier Science Ltd, 2020) Ceylan, Deniz; Yilmaz, Selda; Tuna, Gamze; Kant, Melis; Er, Ayse; Ildiz, Aysegul; Verim, BurcuIntroduction: Previous studies showed significant increases in DNA base damage markers and significant alterations in base excision repair enzymes in patients with unipolar and bipolar depression. We aimed to investigate changes in urine 8-Oxo-2'-deoxyguanosine (8-oxo-dG) and gene expression levels of 8-Oxoguanine DNA glycosylase 1 (OGG1) during a current depressive episode and after remission in bipolar and unipolar disorders. Methods: Twenty-four acutely depressed bipolar (BD), 33 unipolar depression (UD) patients and 61 healthy controls were included in the study. Clinical evaluations, blood and urine sampling were completed at baseline and at remission after eight weeks. The urine 8-oxo-dG levels were assessed by liquid chromatography tandem mass spectrometry and adjusted for urine creatinine levels. The gene expression levels of OGG1 were determined from cDNA extracted from blood samples, using real time-polymerase chain reaction. Results: At baseline, patients presented significantly higher levels of 8-oxo-dG (p = 0.008), and lower gene expression of OGG1 (p = 0.024) compared to controls. Levels of either 8-oxo-dG or OGG1 expression did not differ between BD and UD. In patients who remitted by the 8th week (n = 30), 8-oxo-dG decreased significantly (p = 0.001), and gene expression levels of OGG1 increased by 2.95 times compared to baseline levels (p = 0.001). All comparisons were adjusted for age, sex, smoking status and body mass index. Conclusion: Our results suggest that patients with bipolar and unipolar mood disorders present increased 8-oxo-dG and decreased gene expression levels of OGG1 in current depressive episodes, and that these changes might be reversed by the resolution of depressive symptoms. The causal relationship between DNA damage and repair requires further exploration.Article Citation - WoS: 1Citation - Scopus: 1Alterations of Store-Operated Calcium Entry and Cyclopiazonic Acid-Induced Endothelium-Derived Relaxations in Aging Rat Thoracic Aorta(Akademiai Kiado Zrt, 2016) Erac, Y.; Selli, C.; Tosun, MetinerThe purpose of our study was to investigate whether endothelium-derived relaxations induced by store depletion are altered in aging rat thoracic aorta. Vascular responses were measured in aortic segments isolated from young (2-4 month) and old (20-24 month) male Sprague-Dawley rats. In phenylephrine-contracted intact tissues, receptor-mediated and receptor-independent endothelium-derived relaxations were induced by acetylcholine (ACh) and sarcoplasmic/endoplasmic reticulum Ca2+ ATPase (SERCA) blocker cyclopiazonic acid (CPA), respectively. In addition, CPA-induced changes in intracellular calcium levels were monitored in fura-2-loaded endothelium-denuded tissues. Real-time quantitative reverse transcription polymerase chain reaction and western blot analysis were performed to determine the transient receptor potential canonical (TRPC) 4 mRNA and protein levels. Endothelial TRPC4 mRNA levels were apparently decreased in aging rats. Immunoblot analysis showed that TRPC4 protein levels significantly decreased in intact aorta from 20- to 24-month-old rats compared to that from 2- to 4-month-old rats. ACh- and CPA-induced endothelium-dependent relaxations decreased in old rat aorta without any change in direct vasodilation induced by sodium nitroprusside. Store-operated Ca2+ entry (SOCE) induced by CPA was significantly decreased, whereas sarcoplasmic reticulum Ca2+ release was unaffected in endothelium-denuded aging rat aorta. In conclusion, TRPC4 downregulation could be associated with decreased endothelium-dependent vasorelaxations. As endothelial nitric oxide synthase is activated by SOCE-induced caveolar internalization, tracking the expression levels of SERCA, ion channels, and/or associated proteins involved in SOCE would lead to the development of novel therapeutics for age-related vasospastic disorders with dysfunctional endothelium.Article Citation - WoS: 18Citation - Scopus: 18Altered Gamma and Theta Oscillations During Multistable Perception in Schizophrenia(Elsevier, 2020) Rurup, Linda; Mathes, Birgit; Schmiedt-Fehr, Christina; Wienke, Annika Susann; Ozerdem, Aysegul; Brand, Andreas; Başar Eroğlu, CananObjective: Coherent object perception in patients with schizophrenia is known to be impaired. Oscillatory brain dynamics constitute a fundamental mechanism for the coordinated communication of neural circuits. Such dynamics have been proposed to reflect impaired spatio-temporal integration of sensory and cognitive processes during object perception in schizophrenia. Method: EEG recordings of patients with schizophrenia (n = 23) and control participants (n = 23) were examined. Presented were either an ambiguous (multistable) stimulus, endogenously inducing switching between two perceptual alternatives, or a slightly modified unambiguous control stimulus, during which perceptual reversals were triggered by a minor change in the stimulus configuration. Event-related amplitude modulation induced by perceptual reversals was analyzed for theta (3-8 Hz) and gamma band oscillations (28-48 Hz). Results: Patients displayed increased reaction times and more errors when indicating unambiguous reversals. The patients ' amplitude enhancement of theta oscillations was diminished in both task conditions. During the control task were gamma amplitudes larger in patients than in healthy participants. Conclusion: The results indicate that impairments in generating coherent percepts are reflected in alterations of multiple frequency bands and time windows. Changes in gamma band oscillations may reflect the patients' impairments in perceptuo-cognitive integration processes. Diminished theta amplitude modulation in patients further emphasize diminished top-down cognitive control during perceptual reversals. Significance: This study provides insight into how theta and gamma oscillations underlie changes in object perception, and thereby possibly the generation of core symptoms, in schizophrenia. This paper is dedicated to Prof. Dr. Erol Basar, a pioneer in research on oscillatory braindynamics. He was tireless in his effort to understand brain functions and integratedphilosophy, physics, biology and psychology in his research. His vision on how informationis coded in brain networks inspired many researchers in the last 40 years. With him, we not only lose an exceptional researcher, but also a supportive academic teacher and mentor with a persistent, prolific enthusiasm for international and collaborative projects.Review Article Citation - WoS: 10Citation - Scopus: 11Alzheimer's Disease Research Progress in the Mediterranean Region: the Alzheimer's Association International Conference Satellite Symposium(Wiley, 2022) Sexton, Claire; Solis, Michele; Aharon-Peretz, Judith; Alexopoulos, Panagiotis; Yener, Görsev; Bayen, Eleonore; Birkenhager, BettyAs research and services in the Mediterranean region continue to increase, so do opportunities for global collaboration. To support such collaborations, the Alzheimer's Association was due to hold its seventh Alzheimer's Association International Conference Satellite Symposium in Athens, Greece in 2021. Due to the COVID-19 pandemic, the meeting was held virtually, which enabled attendees from around the world to hear about research efforts in Greece and the surrounding Mediterranean countries. Research updates spanned understanding the biology of, treatments for, and care of people with Alzheimer's disease (AD_ and other dementias. Researchers in the Mediterranean region have outlined the local epidemiology of AD and dementia, and have identified regional populations that may expedite genetic studies. Development of biomarkers is expected to aid early and accurate diagnosis. Numerous efforts have been made to develop culturally specific interventions to both reduce risk of dementia, and to improve quality of life for people living with dementia.
