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Citation Count: 102
A 1.6-mm, metal tube ultrasonic motor
(Ieee-inst Electrical Electronics Engineers inc, 2003) Cagatay, S; Koc, B; Uchino, K
A miniaturized metal tube ultrasonic motor, the dimensions of which are 1.6 mm in diameter and 6 rum in length, was developed. Two flattened surfaces with 90-degrees were ground on the outer surface of the stator. Two PZT-based piezoelectric ceramics were bonded onto these flat surfaces. The asymmetrical surface of the stator developed the split of the two degenerated orthogonal bending modes, resulting in a wobble motion. The working frequency of the 1.6-mm motor with 6 mm in length was 130 kHz. A torque of 0.5 mNm was reached at a maximum power of 45 mW with a speed of 45 rad/sec. The maximum efficiency was 16%.
Citation Count: 4
3D Bioprinting tissue analogs: Current development and translational implications
(Sage Publications inc, 2023) Liu, Suihong; Cheng, Lijia; Liu, Yakui; Zhang, Haiguang; Song, Yongteng; Park, Jeong-Hui; Ramalingam, Murugan
Three-dimensional (3D) bioprinting is a promising and rapidly evolving technology in the field of additive manufacturing. It enables the fabrication of living cellular constructs with complex architectures that are suitable for various biomedical applications, such as tissue engineering, disease modeling, drug screening, and precision regenerative medicine. The ultimate goal of bioprinting is to produce stable, anatomically-shaped, human-scale functional organs or tissue substitutes that can be implanted. Although various bioprinting techniques have emerged to develop customized tissue-engineering substitutes over the past decade, several challenges remain in fabricating volumetric tissue constructs with complex shapes and sizes and translating the printed products into clinical practice. Thus, it is crucial to develop a successful strategy for translating research outputs into clinical practice to address the current organ and tissue crises and improve patients' quality of life. This review article discusses the challenges of the existing bioprinting processes in preparing clinically relevant tissue substitutes. It further reviews various strategies and technical feasibility to overcome the challenges that limit the fabrication of volumetric biological constructs and their translational implications. Additionally, the article highlights exciting technological advances in the 3D bioprinting of anatomically shaped tissue substitutes and suggests future research and development directions. This review aims to provide readers with insight into the state-of-the-art 3D bioprinting techniques as powerful tools in engineering functional tissues and organs.
Citation Count: 33
Accuracy assessment of temperature trends from ERA5 and ERA5-Land
(Elsevier, 2023) Yilmaz, Meric; Civil Engineering
Many environmental processes and ecological systems are being affected by the warming temperatures as a result of climate change. To correctly identify and attribute the uncertainty estimates in these systems, an investigation of tem-perature trend signal existing in the datasets that are used to study such systems is necessary. In this study, the trend of widely used ERA5 and ERA5-Land temperature estimates between 1951 and 2020 were validated using temperature trends from ground station-based observations in Turkey. The investigation included datasets obtained over 540 stations, and the seasonality and spatio-temporal variability of the trend accuracy was also investigated. On average, the trends of observations over all stations were 0.82 degrees C/decade and 0.30 degrees C/decade for the periods 2001-2020 and 1951-2020, respectively, indicating strong evidence of climate change. When the model datasets used spatially and temporally continuous datasets, the trends identified were 0.91 degrees C/decade and 0.21 degrees C/decade over the entire Turkey for the years 2001-2020 and 1951-2020, respectively. The difference in the 70-year trends of the two esti-mates was attributed to the missing datasets in observations. The differences between the trends of model estimates and observations were higher for the first decade than for the last two decades, stressing the impact of improved model estimates over time. All products showed heavy seasonality, suggesting that winter trends (1.3 degrees C/decade on average) are much higher than the summer (0.3 degrees C/decade) between 2001 and 2020. The results indicated a high degree of consistency between the trends of ERA5/ERA5-Land and observations, implying they may be used as a replacement to observations.
Citation Count: 16
ACPA decreases non-small cell lung cancer line growth through Akt/PI3K and JNK pathways in vitro
(Springernature, 2021) Boyacioglu, OEzge; Bilgic, Elif; Varan, Cem; Bilensoy, Erem; Nemutlu, Emirhan; Sevim, Duygu; Korkusuz, Petek; Basic Sciences
Therapeutic agents used for non-small cell lung cancer (NSCLC) have limited curative efficacy and may trigger serious adverse effects. Cannabinoid ligands exert antiproliferative effect and induce apoptosis on numerous epithelial cancers. We confirmed that CB1 receptor (CB1R) is expressed in NSCLC cells in this study. Arachidonoylcyclopropylamide (ACPA) as a synthetic, CB1R-specific ligand decreased proliferation rate in NSCLC cells by WST-1 analysis and real-time proliferation assay (RTCA). The half-maximal inhibitory concentration (IC50) dose of ACPA was calculated as 1.39x10(-12)M. CB1 antagonist AM281 inhibited the antiproliferative effect of ACPA. Flow cytometry and ultrastructural analyzes revealed significant early and late apoptosis with diminished cell viability. Nano-immunoassay and metabolomics data on activation status of CB1R-mediated pro-apoptotic pathways found that ACPA inhibited Akt/PI3K pathway, glycolysis, TCA cycle, amino acid biosynthesis, and urea cycle and activated JNK pathway. ACPA lost its chemical stability after 24hours tested by liquid chromatography-mass spectrometry (LC-MS/MS) assay. A novel ACPA-PCL nanoparticle system was developed by nanoprecipitation method and characterized. Sustained release of ACPA-PCL nanoparticles also reduced proliferation of NSCLC cells. Our results demonstrated that low dose ACPA and ACPA-PCL nanoparticle system harbor opportunities to be developed as a novel therapy in NSCLC patients that require further in vivo studies beforehand to validate its anticancer effect.
Citation Count: 2
Adaptation of Food Craving Inventory to Turkish culture: a validity and reliability study
(Bmc, 2022) Ozel, Irem Cagla; Yabanci Ayhan, Nurcan; Cetiner, Ozlem; Nutrition and Dietetics
Plain English Summary This study was carried out to adapt the Food Craving Inventory to Turkish. The English version of inventory consists of 4 sub-factors that measure cravings for high-fat foods, carbohydrates/starches, sweets, and fast food fats, and creates a total score. The sample of the study consists of 621 individuals between the ages of 19-50 who voluntarily agree to participate in an online survey. This study revealed that FCI-TR is a valid instrument of specific food cravings in the Turkish adult population. Turkish version of the FCI also consist of 4 sub-factors. Women experienced more food craving for sweets than men. While the most craved food by women was chocolate, men scored significantly higher on bread than women. In addition, a relationship was found between food craving and body weight. Introduction The Food Craving Inventory is a 28-item self-report measure of specific food cravings. The inventory consists of 4 factors: high fats, sweets, carbohydrates/starches and fast-food fats. Purpose This study was carried out to evaluate the Turkish validity and reliability of the Food Craving Inventory, and to determine the psychometric properties and factor structure of the Turkish version. Methods The sample of the study consists of 621 individuals between the ages of 19-50 who voluntarily agree to participate in online survey. Validity and reliability analyses were performed for the Turkish version of Food Craving Inventory (FCI-TR). Confirmatory factor analysis was performed to evaluate the factor structure of the Turkish version of FCI. Results Confirmatory factor analysis yielded a four-factor structure as "sweets," "high-fats," "carbohydrates/starches" and "fast food fats". The Cronbach-alpha coefficient for the total score was 0.84; subfactors were calculated as 0.74 for "sweets", 0.64 for "high-fat foods", 0.65 for "carbohydrates/starches", and 0.66 for "fast-food fats". The scores of the FCI-TR factors and its total score significantly correlated with the sub-factors of Three Factor Eating Questionnaire (TFEQ). A significant correlation was found between body mass index (BMI) and high fats and fast-food fats factor score. Also total and factor scores of the FCI-TR were different between BMI groups. Conclusions This study demonstrates that the Turkish version of the FCI is a valid and reliable tool to measure food cravings in the Turkish population. FCI is also correlated with sub-factors of TFEQ.
Citation Count: 1
Adaptive Stimulus Design for Dynamic Recurrent Neural Network Models
(Frontiers Media Sa, 2019) Doruk, R. Ozgur; Zhang, Kechen; Electrical-Electronics Engineering
We present an adaptive stimulus design method for efficiently estimating the parameters of a dynamic recurrent network model with interacting excitatory and inhibitory neuronal populations. Although stimuli that are optimized for model parameter estimation should, in theory, have advantages over nonadaptive random stimuli, in practice it remains unclear in what way and to what extent an optimal design of time-varying stimuli may actually improve parameter estimation for this common type of recurrent network models. Here we specified the time course of each stimulus by a Fourier series whose amplitudes and phases were determined by maximizing a utility function based on the Fisher information matrix. To facilitate the optimization process, we have derived differential equations that govern the time evolution of the gradients of the utility function with respect to the stimulus parameters. The network parameters were estimated by maximum likelihood from the spike train data generated by an inhomogeneous Poisson process from the continuous network state. The adaptive design process was repeated in a closed loop, alternating between optimal stimulus design and parameter estimation from the updated stimulus-response data. Our results confirmed that, compared with random stimuli, optimally designed stimuli elicited responses with significantly better likelihood values for parameter estimation. Furthermore, all individual parameters, including the time constants and the connection weights, were recovered more accurately by the optimal design method. We also examined how the errors of different parameter estimates were correlated, and proposed heuristic formulas to account for the correlation patterns by an approximate parameter-confounding theory. Our results suggest that although adaptive optimal stimulus design incurs considerable computational cost even for the simplest excitatory-inhibitory recurrent network model, it may potentially help save time in experiments by reducing the number of stimuli needed for network parameter estimation.
Citation Count: 0
Akciğer kanserinde immünoterapi ve tedavide multidisipliner yaklaşım
(Turkish Assoc Tuberculosis & Thorax, 2020) Karadurmuş, Nuri; Kaya, Akın; Göksel, Tuncay; Yılmaz, Ülkü; Tülek, Necla; Basic Sciences
Akciğer kanseri dünya genelinde kanserle ilişkili ölümlerin başlıca nedeniolmaya devam etmektedir. Son 20 yılda kanser biyolojisi ve patogenezi hakkındaki bilgiler artmış, immün kontrol noktası inhibitörleri (İKNİ) kullanımasunulmuş ve böylece solid kanserlerin tedavisinde önemli bir dönem başlamıştır. Bu derlemede; tedavide yenilikler, immünoterapi ve tedavide multidisipliner yaklaşım çerçevesinde akciğer kanseri ele alınmıştır. Küçük hücreli dışıakciğer kanseri (KHDAK) en sık görülen ve özellikleri nedeniyle İKNİ tedavisinden ideal olarak yararlanabilecek akciğer kanseri türü olması nedeniyleyazının odak noktasını oluşturmuştur. Bu derleme, akciğer kanseri tedavisindeimmünoterapi yaklaşımının göğüs hastalıkları başta olmak üzere tüm branşlarda multidisipliner farkındalığını artırmayı ve yönetimi hakkında bilgi sağlamayıamaçlayan ilk Türkçe derlemedir. Ayrıca bu derleme, KHDAK tedavisinde İKNİkullanımına ilişkin son klinik çalışmaların dikkat çekici sonuçlarını sunmasıaçısından önem teşkil etmektedir. İmmünoterapi kanser tedavisinde yeni bir dönem başlatmıştır ve İKNİ tedavisinin kendine özgü etki mekanizması yeni bazı advers olay grubunun ortaya çıkmasına nedenolmuştur, bunlar arasında pnömonitis özellikle önemlidir ve advers olaylar konusunda gerektiğinde hastaların ilgili uzmanlık dalları ilekonsülte edilmesi gerekmektedir. Akciğer kanserinde tedavi, hastanın özellikleri, histolojik özellikler, genetik durum göz önünde bulundurularak her bir hastaya özel planlanmalı ve akciğer kanserli bir hastanın tanısal değerlendirilmesi ve en uygun şekilde tedavisi içingöğüs hastalıkları, göğüs cerrahisi, tıbbi onkoloji, radyasyon onkolojisi, patoloji ve radyoloji uzmanlık dalları arasında işbirliği sağlanmalıdır. Bununla birlikte, aile hekimleri de akciğer kanserinin erken tanınmasında ve ayrıca hastalarını tütün bırakmayı teşvik ederekkanserin önlenmesinde önemli rol oynayabilirler. Ayrıca, toplumda farkındalık yaratmak ve erken tanı için akciğer kanseri yönündentarama çalışmaları yapmak hedeflenmelidir
Citation Count: 10
Alkaline Hydrothermal Synthesis, Characterization, and Photocatalytic Activity of TiO₂ Nanostructures: The Effect of Initial TiO₂ Phase
(Amer Scientific Publishers, 2019) Erdogan, Nursev; Park, Jongee; Choi, Woohyuk; Kim, Soo Young; Ozturk, Abdullah; Metallurgical and Materials Engineering
One-dimensional (1D) titanate nanostructures were synthesized by hydrothermal route, using commercially available TiO2 (P25) and anatase powders as precursor materials and strong NaOH solution as catalyzer. The prepared titanates were calcined, followed by protonation to produce TiO2 nanostructures having enhanced photocatalytic and photovoltaic properties. The synthesized TiO2 1D nanostructures were characterized using field-emission scanning electron microscope, high-resolution electron microscope, X-ray diffraction analysis, and UV-Vis photospectroscopy to understand the effect of initial TiO2 phase on morphological and crystallographic features, and bandgap. Methylene blue degradation test was applied to evaluate the photoactivity of the products obtained after different stages of the process. The findings indicate that 1D TiO2 nanostructures form by different mechanisms from dissolved aggregates during hydrothermal process, depending on the crystal structure of the initial precursor used. Photocatalytic test results reveal that protonated titanates have considerable adsorption capability, while photocatalytic degradation depends on TiO2 transformation.
Citation Count: 78
Amine grafted silica supported CrAuPd alloy nanoparticles: superb heterogeneous catalysts for the room temperature dehydrogenation of formic acid
(Royal Soc Chemistry, 2015) Yurderi, Mehmet; Bulut, Ahmet; Caner, Nurdan; Celebi, Metin; Kaya, Murat; Zahmakiran, Mehmet; Chemical Engineering
Herein we show that a previously unappreciated combination of CrAuPd alloy nanoparticles and amine-grafted silica support facilitates the liberation of CO-free H-2 from dehydrogenation of formic acid with record activity in the absence of any additives at room temperature. Furthermore, their excellent catalytic stability makes them isolable and reusable heterogeneous catalysts in the formic acid dehydrogenation.
Citation Count: 58
Analysis of bakery products by laser-induced breakdown spectroscopy
(Elsevier Sci Ltd, 2015) Bilge, Gonca; Boyaci, Ismail Hakki; Eseller, Kemal Efe; Tamer, Ugur; Cakir, Serhat; Department of Electrical & Electronics Engineering
In this study, we focused on the detection of Na in bakery products by using laser-induced breakdown spectroscopy (LIBS) as a quick and simple method. LIBS experiments were performed to examine the Na at 589 nm to quantify NaCl. A series of standard bread sample pellets containing various concentrations of NaCl (0.025-3.5%) were used to construct the calibration curves and to determine the detection limits of the measurements. Calibration graphs were drawn to indicate functions of NaCl and Na concentrations, which showed good linearity in the range of 0.025-3.5% NaCl and 0.01-1.4% Na concentrations with correlation coefficients (R-2) values greater than 0.98 and 0.96. The obtained detection limits for NaCl and Na were 175 and 69 ppm, respectively. Performed experimental studies showed that LIBS is a convenient method for commercial bakery products to quantify NaCl concentrations as a rapid and in situ technique. (C) 2015 Elsevier Ltd. All rights reserved.
Citation Count: 23
Analysis of mirror neuron system activation during action observation alone and action observation with motor imagery tasks
(Springer, 2018) Cengiz, Bulent; Vuralli, Doga; Zinnuroglu, Murat; Bayer, Gozde; Golmohammadzadeh, Hassan; Gunendi, Zafer; Arikan, Kutluk Bilge; Department of Mechatronics Engineering
This study aimed to explore the relationship between action observation (AO)-related corticomotor excitability changes and phases of observed action and to explore the effects of pure AO and concurrent AO and motor imagery (MI) state on corticomotor excitability using TMS. It was also investigated whether the mirror neuron system activity is muscle-specific. Fourteen healthy volunteers were enrolled in the study. EMG recordings were taken from the right first dorsal interosseous and the abductor digiti minimi muscles. There was a significant main effect of TMS timing (after the beginning of the movement, at the beginning of motor output state, and during black screen) on the mean motor evoked potential (MEP) amplitude. Mean MEP amplitudes for AO combined with MI were significantly higher than pure AO session. There was a significant interaction between session and TMS timing. There was no significant main effect of muscle on MEP amplitude. The results indicate that corticomotor excitability is modulated by different phases of the observed motor movement and this modulation is not muscle-specific. Simultaneous MI and AO enhance corticomotor excitability significantly compared to pure AO.
Citation Count: 0
Analysis of Publications on Health Information Management Using the Science Mapping Method: A Holistic Perspective
(Mdpi, 2024) Tengilimoglu, Dilaver; Orhan, Fatih; Tekin, Perihan Senel; Younis, Mustafa; Business
Objective: In the age of digital transformation, there is a need for a sustainable information management vision in health. Understanding the accumulation of health information management (HIM) knowledge from the past to the present and building a new vision to meet this need reveals the importance of understanding the available scientific knowledge. With this research, it is aimed to examine the scientific documents of the last 40 years of HIM literature with a holistic approach using science mapping techniques and to guide future research. Methods: This study used a bibliometric analysis method for science mapping. Co-citation and co-occurrence document analyses were performed on 630 academic publications selected from the Web of Science core collection (WoSCC) database using the keyword "Health Information Management" and inclusion criteria. The analyses were performed using the R-based software Bibliometrix (Version 4.0; K-Synth Srl), Python (Version 3.12.1; The Python Software Foundation), and Microsoft (R) Excel (R) 2016. Results: Co-occurrence analyses revealed the themes of personal health records, clinical coding and data quality, and health information management. The HIM theme consisted of five subthemes: "electronic records", "medical informatics", "e-health and telemedicine", "health education and awareness", and "health information systems (HISs)". As a result of the co-citation analysis, the prominent themes were technology acceptance, standardized clinical coding, the success of HISs, types of electronic records, people with HIM, health informatics used by consumers, e-health, e-mobile health technologies, and countries' frameworks and standards for HISs. Conclusions: This comprehensive bibliometric study shows that structured information can be helpful in understanding research trends in HIM. This study identified critical issues in HIM, identified meaningful themes, and explained the topic from a holistic perspective for all health system actors and stakeholders who want to work in the field of HIM.
Citation Count: 6
Analysis of the Hall effect in TlGaTe₂ single crystals
(Iop Publishing Ltd, 2009) Qasrawi, A. F.; Gasanly, N. M.; Department of Electrical & Electronics Engineering
The electrical resistivity and Hall coefficient of p-type TlGaTe2 crystals were measured in the temperature range of 110-320 K. The electrical resistivity, charge carrier density and Hall mobility data for the crystals have been analyzed by means of existing theories and models to determine the extrinsic energy levels, the carrier effective mass, the donor and acceptor concentrations and the dominant scattering mechanism in the crystal as well. The analysis of the temperature-dependent electrical resistivity recorded parallel and perpendicular to the crystal's axis ( c-axis) reflected the existence of energy levels located at 0.26 and at 0.20 eV, respectively. The difference of these two energy levels is due to crystal anisotropy. The energy level at 0.26 eV was found to represent an acceptor level, as confirmed from Hall data analysis. The temperature dependence of the carrier density was analyzed by using the single-donor-single-acceptor model. The latter analysis revealed the carrier effective mass and the acceptor and donor concentrations as 0.73m(0), 4.10 x 10(17) cm(-3) and 1.20 x 10(17) cm(-3), respectively. The Hall mobility of TlGaTe2 is found to be limited by the scattering of hole-acoustic phonon interactions. The calculated theoretical mobility fits to the experimental one under the condition that the acoustic deformation potential is 11.0 eV, which is the energy position of the top of valence band maximum that is formed by the Te 5s states.
Citation Count: 1
Analyzing two decades of intimate partner femicide-suicides in T?rkiye*
(Elsevier Sci Ltd, 2023) Cavlak, Mehmet; Odabasi, Aysun Balseven; Mutlu, Niluefer Dilara Ar; Erbaydar, Nueket Paksoy
Intimate partner femicide-suicide (IPF-S) is an understudied subgroup of homicide-suicide deaths. Limited research has been conducted on IPF-Ss in the Eastern Mediterranean region. This study thus aimed to evaluate the characteristics of IPF-Ss that occurred in Turkiye between 2000 and 2019. IPF-Ss (n = 226) were extracted from electronic news stories. Data on victims, perpetrators, their relationships, and incidents of murder and suicide were collected. Descriptive statistics were calculated, and logistic regression analysis, mortality rates, and proportion of IPF-S in femicide calculations were conducted, showing that 13.3% of the femicides (n = 1699) were IPF-Ss. The IPF-Ss increased in 5-year intervals and were the highest during the 2015-2019 period (62.5%). Victims were married in 48.2% of the cases and 56% were aged <35 years, while 51.3% of the perpetrators were married and 52.6% were aged >40 years. In 42.0% of the cases, the perpetrator lived with the victim. Most (79.2%) of the cases took place in urban settlements, and the perpetrators used firearms in 84.1% of femicide cases. Firearm use was the most common method in cases where IPF-S was planned (OR = 2.98), when the IPF-S method was the same (OR = 29.6), and when the perpetrator committed suicide (OR = 7.82). In addition, it was found that firearm ownership is an important risk factor for IPF-S in Turkiye. Therefore, we recommend legislation to restrict firearms, as well as new measures to prevent illegal access to weapons.
Citation Count: 2
Angiogenic inhibition therapy, a sliding mode control adventure
(Elsevier Ireland Ltd, 2020) Doruk, Resat Ozgur; Electrical-Electronics Engineering
[No Abstract Available]
Citation Count: 2
Anti-Inflammatory, Antioxidant, and Anti-Atherosclerotic Effects of Natural Supplements on Patients with FMF-Related AA Amyloidosis: A Non-Randomized 24-Week Open-Label Interventional Study
(Mdpi, 2022) Romano, Micol; Garcia-Bournissen, Facundo; Piskin, David; Rodoplu, Ulkumen; Piskin, Lizzy; Elzagallaai, Abdelbaset A.; Demirkaya, Erkan
We aimed to evaluate the effect of a combination of natural products on parameters related to inflammation, endothelial dysfunction, and oxidative stress in a cohort of familial Mediterranean fever (FMF) patients with Serum Amyloid A amyloidosis, in a non-randomized, 24-week open-label interventional study. Morinda citrifolia (anti-atherosclerotic-AAL), omega-3 (anti-inflammatory-AIC), and extract with Alaskan blueberry (antioxidant-AOL) were given to patients with FMF-related biopsy-proven AA amyloidosis. Patients were >18 years and had proteinuria (>3500 mg/day) but a normal estimated glomerular filtration rate (eGFR). Arterial flow-mediated dilatation (FMD), carotid intima media thickness (CIMT), and serum biomarkers asymmetric dimethylarginine (ADMA), high sensitivity C-reactive protein (hs-CRP), pentraxin (PTX3), malondialdehyde (MDA), Cu/Zn-superoxide dismutase (Cu/Zn-SOD), and glutathione peroxidase (GSH-Px) were studied at baseline and after 24 weeks of treatment. A total of 67 FMF-related amyloidosis patients (52 male (77.6%); median age 36 years (range 21-66)) were enrolled. At the end of a 24-week treatment period with AAL, AIC, and AOL combination therapy, ADMA, MDA, PTX3, hsCRP, cholesterol, and proteinuria were significantly decreased compared to baseline, while CuZn-SOD, GSH-Px, and FMD levels were significantly increased. Changes in inflammatory markers PTX3, and hsCRP were negatively correlated with FMD change, and positively correlated with decreases in proteinuria, ADMA, MDA, cholesterol, and CIMT. Treatment with AAL, AIC and AOL combination for 24 weeks were significantly associated with reduction in inflammatory markers, improved endothelial functions, and oxidative state. Efficient control of these three mechanisms can have long term cardiovascular and renal benefits for patients with AA amyloidosis.
Citation Count: 19
Antibacterial Performance of PCL-Chitosan Core-Shell Scaffolds
(Amer Scientific Publishers, 2018) Ozkan, Ozan; Sasmazel, Hilal Turkoglu; Metallurgical and Materials Engineering
In this study, antibacterial performance of the coaxially electrospun Poly-epsilon-caprolactone (PCL)-chitosan core-shell scaffolds developed, optimized and identified physically and chemically in our previous study, were evaluated for the suitability in wound healing applications. The aim of utilizing a core-shell fibrous scaffold with PCL as core and chitosan as shell was to combine natural biocompatibility, biodegradability and antibacterial properties of chitosan with mechanical properties and resistance to enzymatic degradation of PCL. The scaffolds were prepared with the optimized parameters, obtained from our previous study. Thickness and contact angle measurements as well as Scanning Electron Microscopy (SEM) and Transmission Electron Microscopy (TEM) analyses confirmed repeated fabrication of PCL-chitosan core-shell scaffolds. In this study, assays specific to wound dressing materials, such as water vapor transmission rate (WVTR), in vitro degradability and antibacterial tests were carried out. WVTR value of PCL-chitosan core-shell scaffolds was higher (2315 +/- 3.4 g/m(2).day) compared to single PCL scaffolds (1654 +/- 3.2 g/m(2).day) due to the higher inter-fiber pore size. Additionally, in vitro degradability assays showed that the susceptibility of chitosan to enzymatic degradation can be significantly improved by hybridization with more resistant PCL while still keeping the scaffold to be considered as biodegradable. Finally, inhibition ratio and inhibition zone measurements showed that the PCL-chitosan core-shell polymeric scaffolds had significant antibacterial performance (52.860 +/- 2.298% and 49.333 +/- 0.719% inhibition ratios; 13.975 +/- 0.124 mm and 12.117 +/- 0.133 mm clear inhibition zones, against E. coli and S. aureus, respectively), close to the native chitosan. Therefore, the developed scaffolds can be considered as suitable candidates for biodegradable wound dressing applications.
Citation Count: 6
Antibiotic administration in targeted nanoparticles protects the faecal microbiota of mice
(Royal Soc Chemistry, 2021) Borsa, Baris A.; Sudagidan, Mert; Aldag, Mehmet E.; Baris, Isik I.; Acar, Elif E.; Acuner, Cagatay; Ozalp, Veli C.; Basic Sciences
Antibiotic therapy comes with disturbances on human microbiota, resulting in changes of bacterial communities and thus leading to well-established health problems. In this study, we demonstrated that targeted teicoplanin administration maintains the faecal microbiota composition undisturbed in a mouse model while reaching therapeutic improvements for S. aureus infection.
Citation Count: 0
Anticipatory 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, Bülent; Department of Mechatronics Engineering
Background/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.
Citation Count: 0
Antiproliferative activity of platinum(II) and copper(II) complexes containing novel biquinoxaline ligands
(Oxford Univ Press, 2024) El-Beshti, Hager Sadek; Gercek, Zuhal; Kayi, Hakan; Yildizhan, Yasemin; Cetin, Yuksel; Adiguzel, Zelal; Ozalp-Yaman, Seniz; Chemical Engineering
Nowadays, cancer represents one of the major causes of death in humans worldwide, which renders the quest for new and improved antineoplastic agents to become an urgent issue in the field of biomedicine and human health. The present research focuses on the synthesis of 2,3,2MODIFIER LETTER PRIME,3MODIFIER LETTER PRIME-tetra(pyridin-2-yl)-6,6MODIFIER LETTER PRIME-biquinoxaline) and (2,3,2MODIFIER LETTER PRIME,3MODIFIER LETTER PRIME-tetra(thiophen-2-yl)-6,6MODIFIER LETTER PRIME-biquinoxaline) containing copper(II) and platinum(II) compounds as prodrug candidates. The binding interaction of these compounds with calf thymus DNA (CT-DNA) and human serum albumin were assessed with UV titration, thermal decomposition, viscometric, and fluorometric methods. The thermodynamical parameters and the temperature-dependent binding constant (KMODIFIER LETTER PRIMEb) values point out to spontaneous interactions between the complexes and CT-DNA via the van der Waals interactions and/or hydrogen bonding, except Cu(ttbq)Cl2 for which electrostatic interaction was proposed. The antitumor activity of the complexes against several human glioblastomata, lung, breast, cervix, and prostate cell lines were investigated by examining cell viability, oxidative stress, apoptosis-terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling, in vitro migration and invasion, in vitro-comet DNA damage, and plasmid DNA interaction assays. The U87 and HeLa cells were investigated as the cancer cells most sensitive to our complexes. The exerted cytotoxic effect of complexes was attributed to the formation of the reactive oxygen species in vitro. It is clearly demonstrated that Cu(ttbq)Cl2, Pt(ttbq)Cl2, and Pt(tpbq)Cl2 have the highest DNA degradation potential and anticancer effect among the tested complexes by leading apoptosis. The wound healing and invasion analysis results also supported the higher anticancer activity of these two compounds. Graphical Abstract Antitumor activity of biqunoxaline complexes.

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