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Article Alzheimer Hastalığında Kallikrein-6, 7 ve Potasyum Kanal Proteinlerinin Olası Rolü(2021) Bulduk, Erkut Baha; Yıldırım, Zuhal; Yıldırım, FilizObjective: Although the formation mechanism of Alzheimer’s Disease (AD) is not known with certainty, two major proteins, beta amyloid of senile plaques and tau protein of neurofibrillary tangels are responsible for AD. One of the major factors in the development of the disease is the formation of in soluble amyloid deposits, and the other one is the increased tau phosphorylation. Kallikreins (KLK’s) are a sub-family of serine proteases that play a role in the etiology of AD which is characterized by neuronal damage and loss of function.Kallikrein (KLK)-6 and KLK-7 are known to be age-related protease and are found at high levels in the central nervous system (CNS). It was previously shown to be involved in proteolysis of extracellular proteins implicated in neurodegenerative diseases such as AD. In this study, we aimed to investigate the possible role of KLK-6 and KLK-7 in the pathogenesis of AD and the relationship between potassium channel proteins. Methods: A total of 35 Alzheimer’s patients over the age 65 years, followed-up by Polatlı Duatepe Government Hospital and 35 healthy individuals (control group) admitted to the neurology clinic for routine screening with cognitive status considered normal were included in this study. After a 12-hour hunger, KLK-6 and KLK-7 were measured with inwardly rectifying potassium channel protein (KCNJ3), and two-pore potassium channel protein (KCNK9) levels were measured by the Enzyme-Linked Immuno Sorbent Assay (ELISA) in the serum of the blood samples which were taken from the antecubital vein after centrifuging for 10 minutes at 2500xg. The differences between the two groups were tested by T- test. A value of p<0.05 was considered statistically significant. Results: All the groups were matched for age and gender, but not statistically significant difference was observed (p>0.05). According to our findings, serum KLK- 6 and KLK-7 levels of Alzheimer’s group were significantly increased (p<0.05). A significant difference was not detected when the levels of serum KCNJ3 and KCNK9 of the Alzheimer’s group compared with the control group (p>0.05). Conclusion: It is thought that the failure in preventing the abnormal protein folding and accumulation leads to AD in the brain. According to the findings of the present study, a positive correlation was detected between the levels of KLK-6 and KLK-7 and AD’s pathology.Article Neuron Modeling: Estimating the Parameters of a Neuron Model From Neural Spiking Data(Tubitak Scientific & Technological Research Council Turkey, 2018) Doruk, Resat Ozgur; Doruk, OzgurWe present a modeling study aiming at the estimation of the parameters of a single neuron model from neural spiking data. The model receives a stimulus as input and provides the firing rate of the neuron as output. The neural spiking data will be obtained from point process simulation. The resultant data will be used in parameter estimation based on the inhomogeneous Poisson maximum likelihood method. The model will be stimulated by various forms of stimuli, which are modeled by a Fourier series (FS), exponential functions, and radial basis functions (RBFs). Tabulated results presenting cases with different sample sizes (# of repeated trials), stimulus component sizes (FS and RBF), amplitudes, and frequency ranges (FS) will be presented to validate the approach and provide a means of comparison. The results showed that regardless of the stimulus type, the most effective parameter on the estimation performance appears to be the sample size. In addition, the lowest variance of the estimates is obtained when a Fourier series stimulus is applied in the estimation.Article Citation - WoS: 8Citation - Scopus: 10Nöromüsküler Hastalarda Gövde Kontrolünün Değerlendirilmesi: Gövde Bozukluk Ölçeği’nin Geçerlik ve Güvenirliği(Turkish Neurological Soc, 2018) Demir, Yasemin Parlak; Yıldırım, Sibel AksuAmaç: Çalışmamızın amacı Gövde Bozukluk Ölçeği’nin (GBÖ) erişkin nöromüsküler hastalıklarda geçerlik ve güvenirliğini araştırmaktır. Gereç ve Yöntem: Çalışmaya 66 nöromüsküler hastalık tanısı olan birey alındı. Çalışmaya dahil edilen olgulara GBÖ, Manuel Kas Testi (gövde, üst ve alt ekstremite), Motor Fonksiyon Değerlendirme Ölçeği (MFM), Fonksiyonel Bağımsızlık Ölçeği (FIM), Rivermead Mobilite İndeksi (RMI) yapıldı. Bulgular: GBÖ’nün test tekrar test, ICC güvenirlikleri mükemmel bulundu (GBÖ: 0,96 ve 0,98). Cronbach alfa katsayısı 0,82 bulundu. Yapı geçerliği için GBÖ ile MFM (r=0,29), MFM gövde (r=0,31), toplam gövde kas kuvveti (r=0,34), toplam alt ekstremite kas kuvveti (r=0,34, p<0,05), toplam kas kuvveti (gövde, alt ve üst ekstremite) (r=0,52, p<0,05) arasında anlamlı ilişki bulundu. GBÖ uyum geçerliği için FIM (r=0,32, p<0,05) ve RMI (r=0,39, p<0,05) ile ilişkili bulundu. Sonuç: Çalışmanın sonucunda GBÖ’nün erişkin kas hastalıklarında yapı ve uyum geçerliliğinin olduğu ve mükemmel güvenirliğe sahip olduğu bulundu. GBÖ rehabilitasyon kliniklerinde uygulaması kolay ve kısa zaman alan bir ölçektirArticle Citation - WoS: 1Citation - Scopus: 1Anticipatory Effect of Execution on Observation: an Approach Using Exopinch Finger Robot(Tubitak Scientific & Technological Research Council Turkey, 2019) Arıkan, Kutluk Bilge; Zadeh, Hassan Gol Mohammad; Turgut, Ali Emre; Zinnuroğlu, Murat; Bayer, Gözde; Günendi, Zafer; Cengiz, BülentBackground/aim: This study aims to explore the mirror neuron system (MNS) involvement using mu (8–12 Hz)/beta (15–25 Hz) bandsuppression in an action observation-execution paradigm.Materials and methods: Electrophysiological (EEG) data from 16 electrodes were recorded while 8 participants observed video clips ofa hand squeezing a spring. Specifically, the effect of anticipated execution on observation was studied. For this purpose, a fully actuatedfinger exoskeleton robot was utilized to synchronize observation and execution and to control the execution condition for the participants. Anticipatory effect was created with a randomized robot accompany session.Results: The results showed that the observational condition (with or without anticipation) interacted with hemisphere at central channels near somatosensory cortex. Additionally, we explored the response of MNS on the kinetics features of visual stimuli (hard or softspring).Conclusion: The results showed an interaction effect of kinetics features and hemisphere at frontal channels corresponding nearly tothe ventral premotor cortex area of the brain. The activation of mirror neurons in this area plays a crucial role in observational learning.Based on our results, we propose that specific type of visual stimuli can be combined with the functional abilities of the MNS in the action observation based treatment of hand motor dysfunction of stroke patients to have a positive additional impact.Article Citation - WoS: 4Citation - Scopus: 4Neuroprotective effects of adrenomedullin in experimental traumatic brain injury model in rats(Turkish Assoc Trauma Emergency Surgery, 2022) Emmez, Gokcen; Bulduk, Erkut Baha; Yildirim, ZuhalBACKGROUND: Traumatic brain injuries cause damages in the brain in several ways, which include cell death because of edema, disruption of the blood-brain barrier, shear stress, and ischemia. In this study, we investigated the effects of adrenomedullin (AM) on oxidative stress and inflammation after head traumas in a rat model. METHODS: Eighteen male adult Wistar albino rats were randomized into three groups (n=6). No traumas were applied to the control (C) group. Traumas were applied in line with Marmarau trauma model in the trauma group. The rats in the AM treatment group were treated with post-traumatic 12 mu g/kg i.p. AM in addition to the trauma group. The rats were followed for 7 days in all groups and were then sacrificed. Brain tissues and blood samples were taken. RESULTS: In the trauma group, both tissue and serum MDA, TNF-alpha, and IL-6 levels were significantly increased compared to the control group (p<0.05). In the AM-treated group, serum TNF-alpha levels were significantly decreased compared to the trauma group (p<0.05). In the trauma group, both tissue and serum GSH levels were significantly decreased compared to the control group (p<0.05). In the trauma group, serum Vitamin D3 levels were significantly decreased compared to the control group (p<0.05). In the AM-treated group, both tissue and serum GSH levels were significantly increased compared to the trauma group (p<0.05). CONCLUSION: These results indicate that AM has neuroprotective effects on traumatic brain injury in a rat model.Article Early Impairment of Right Ventricular Functions in Patients With Moderate Asthma and the Role of Isovolumic Acceleration(2022) Karasu, Betül Banu; Ayhan, Hüseyin; Ayhan, Hüseyin; Ayhan, HüseyinIntroduction: Asthma is a common chronic lung disease that affects people all over the world. Pulmonary hyper- tension and right ventricular (RV) dysfunction are possible complications that may develop in the advanced stages of asthma. However, the number of studies investigating asthma and its implications on new RV parameters are very rare. This study aims to evaluate the RV functions in patients with moderate asthma before the development of pulmonary hypertension. Patients and Methods: Forty-one patients with moderate asthma and 40 healthy individuals were enrolled in this case-control study. All participants underwent a detailed two-dimensional echocardiographic examina- tion. RV functions were measured through RV isovolumic acceleration (IVA) index in addition to conven- tional parameters. RV IVA, a tissue doppler derived parameter, was calculated as the ratio between maximum isovolumic myocardial velocity during isovolumic contraction and the time interval from the onset of this wave to the time at its maximum velocity. Results: There were no significant differences between the two groups in terms of baseline clinical character- istics, laboratory findings and echocardiographic parameters measuring left ventricular functions (p> 0.05). In asthmatic patients, RV isovolumic relaxation time and RV myocardial performance index were higher (p= 0.027 and p< 0.001 respectively), while RV fractional area change, tricuspid annular plane systolic excur- sion (TAPSE) and RV IVA values were all lower (p< 0.001). RV IVA was found to be inversely proportional to asthma duration. TAPSE [β= 0.632, 95% CI= (0.121) - (0.225), p< 0.001] and pulmonary artery systolic pressure [β= -0.188, 95% CI= (-0.057) - (-0.003), p= 0.032] were shown as independent predictors of RV IVA. Conclusion: Asthma is an important disease that may result in subclinical RV dysfunction even before the development of pulmonary hypertension. RV IVA, an easily obtained and load-independent parameter, may be a useful and reliable index that sensitively analyzes subtle deteriorations in the contractile function of RV in asthmatic patients. RV IVA may also correlate with asthma duration.
