Browsing by Author "Kaya, A"

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    The effect of Electro Magnetic Fields on Cell Behaviour
    Tuglu, MI; Gülbagça, F; Sal, DH; Saygili, S; Sönmez, PK; Aydemir, I; Özkut, M; Öztürk, S; Gümüsay, M; Kaya, A; Keskin, N
    The biologic effects of electomagnetic fields application on medical field has been increased. Their effect on medical treatment depends on cell behaviour which can be observed by in vivo and in vitro studies. Their effect on the stem cells and the cell lines and the organs of experimental animals with morphological alterations are helpful to understand cell behaviour. The behaviour of the cells can be analyse at ultrastructial level by scaning electron microscopy. Application of electomagnetic fields cause increase of proliferation, migrationand improvement of wound healing with beneficial effects while they cause oxidative stress and cell daeth including apoptosis for cancer cells in different types of cell line. The minimal side effect with maximum beneficial treatment of these products suggest that they could be very useful for clinical trials.
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    Design of Pulsed Electromagnetic Field Generator and Applicator and the Effect of Wound Healing
    Kaya, A; Tuglu, MI; Kaya, D
    Today, biomedical devices have become an issue where system manufacturers are working intensively. At present, many domestic and foreign biomedical companies offer various EMA products. Electromagnetic fields (EMF) has a significant impact on our body. These fields are being used for bone problems, cartilage regeneration, and pain removal for physiotherapy purposes. Lately, EMFs are often used in in vitro and in vivo assays. In this study, in vivo test results of the applied pulsed electromagnetic fields (PEMF) with our designed Helmholtz coil array system are given. The skin wound healing conducted in rats as an experimental model provides important information for evaluating the efficacy and mechanism of these kind of treatments. For this purpose, effectiveness of PEMF compared to control groups on experimental skin healing effect was examined macroscopically. Compared with the control groups a faster wound healing process was followed by PEMF application at 75 Hz frequency.
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    Effects of Electromagnetic Fields Application on Experimental Varicocele Model in Rats
    Gülbagça, F; Sal, DH; Saygili, S; Sönmez, PK; Aydemir, I; Özkut, M; Öztürk, S; Gümüsay, M; Kaya, A; Tuglu, MI
    Varicocele is the most clinical condition which can be treated by surgery. The frequency in male is 20%. The half of infertile patient has this pathology which there is dilatation in plexus pampiniformis veins of testes. Varicocele causes increase of heat or increse of oxidative stres in seminifer tubules where they produce pathology for spermatogenesis. Low frequency magnetic fields are useful for the treatment of many area where they become important role. In this study the effect of low frequency magnetic fields on the experimental varicocele model of rat testes was investigated. The parameters for oxidative stres suggest eNOS and iNOS with apoptosis were evaluated by immunohistochemical staining. There was increaese in eNOS, iNOS and apoptosis by the varicocele experiment where there was testicular damage and low frequency magnetic fields caused decrease in oxidative stress and apoptosis. Application of magnetic fields can help the clinical varicocele pathologies either with treatment or supportive effect.
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    Effects of various electromagnetic field applications on the aggressiveness of breast cancer line
    Gümüsay, M; Saygili, S; Aydemir, I; Kaya, A; Tuglu, MI
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    Design of Coils Driven by Pulsed Electromagnetic Field Generator and the Effect of Wound Healing in Rats
    Gümüsay, M; Gülbagça, F; Saygili, S; Aydemir, I; Kaya, A; Tuglu, MI
    Chronic wound healing is an important problem especially in diabetic and the elderly which is needed development of the current treatment methods. Electromagnetic fields (EMF) has a significant impact on our body. These fields are being used for bone problems, cartilage regeneration, and pain removal for physiotherapy purposes. Lately, EMFs are often used in in vitro and in vivo assays. In this study, in vivo test results of the applied pulsed electromagnetic fields (PEMF) with our designed Helmholtz coil array system are given. The skin wound healing conducted in rats as an experimental model provides important information for evaluating the efficacy and mechanism of these kind of treatments. For this purpose, effectiveness of PEMF compared to control groups on experimental skin healing effect was examined macroscopically. Compared with the control groups a faster wound healing process was followed by PEMF application at 75 Hz frequency.
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    Design of Antenna-Applicator for Electromagnetic Field Applications and Excitation Model for Rat and Heat Transfer Analysis
    Gümüsay, M; Gülbagça, F; Aydemir, I; Saygili, S; Kaya, A; Tuglu, MI
    There has been only a few technical progress which contribute to wound healing in the last century. Despite these advances wound healing is very hard issue to study because of its subjectivity, diversity and complexity of the wound healing process and diversity of patients. Molecules are insufficient in the chronic wound and unlike other cells multiplying endothelial cells interrupt the healing process. To restart this process, cells can be excitated by pulsed electromagnetic fields stimulation method. When a suitable frequency and waveform electromagnetic field (EMF) signal is applied to the target tissue with the help of a coil or applicator physiological effects occurs at the cellular size. Low-frequency electromagnetic fields are non-ionizing part of the EM spectrum and they are used as adjunct therapy in soft tissue injuries. In this study, an antenna-applicator design was performed and the effect of non-thermal pulsed radio frequency energy (PRFE) system to the wound created rat skin was examined.
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    A rare case liver hydatid cyst containing multiple calculi
    Kaya, A; Sahin, ST; Coskun, T; Kaya, Y
    The hydatic cyst disease, caused by Echinococcus granulosus, is a potentially lethal, which can be found anywhere in the world, but especially in endemic areas such as the Mediterranean Basin, North Africa, Eastern Europe, the Balkans and Middle East. This parasite is mainly found in the liver (3/4 of the cases), being asymptomatic in most cases and discovered accidentally on a routine abdominal ultrasound or an ultrasound done for diagnosing other pathologies. Liver hydatid cyst threatment is multimodal, which includes medical, surgical, and interventional radiologic techniques.
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    Seawater effect on consistency limits and compressibility characteristics of clays
    Yukselen-Aksoy, Y; Kaya, A; Ören, AH
    The reported results in the literature indicate that there is a discrepancy regarding seawater effect on the consistency limits and compressibility properties of clayey soils having relatively low and high plasticity. To clarify this discrepancy, consistency limits including liquid, plastic and shrinkage limits, sediment volume and compressibility characteristics of ten soils were tested using distilled water and natural seawater from the Aegean Sea. The results indicate that the effect of seawater is negligible on the tested consistency limits and compressibility characteristics of soils when they have liquid limits up to 110%. The seawater effect is most noticed on the consistency limits and compressibility of Na-bentonites. The results of previous research were compiled and compared with those obtained in this study. All reported data were normalized by dividing the index values obtained using seawater by those obtained using distilled water. The comparison of data indicate that the compiled data and present study data are in good agreement, i.e. when the normalized values are plotted as function of liquid limit, all index properties plot along the unity line until the liquid limit of soils is about 110%; then, the normalized index values decrease almost linearly with liquid limit. (C) 2008 Elsevier B.V. All rights reserved.
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    Effects of various parameters on dynamic characteristics in adhesively bonded joints
    Kaya, A; Tekelioglu, MS; Findik, F
    Adhesively bonded lap joints are used extensively in various industries. Some disadvantages like holes, thermal effects occurring in the bolted, welded, riveted, and soldered joints are not in question in adhesively bonded joints. Strong adhesive materials used in bonding have been greatly developed in recent years, and then the properties of lightness, sealing, corrosion resistance, heat and sound isolation, damping, and quickly mounting facility have been highly improved. In this work, effects of various dynamic characteristics in the adhesively bonded joints subjected to dynamic forces are investigated using the finite element method. The investigation is conducted on a three-dimensional model. The finite element model of the joint is obtained using isoparametric three-dimensional elements having eight nodes with three degrees of freedom each. Mesh generation is accomplished automatically in a computer. The joint is modeled as a thin plate clamped from the left side. The in-plane vibration analysis is constructed. First, the natural frequencies and mode shapes are obtained, and then point and transfer receptances are extracted, employing structural damping. It is observed that the damping greatly decreased the resonance amplitudes. (C) 2004 Elsevier B.V. All rights reserved.
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    Comprassion of the Effect of Pulsed Electromagnetic Field and Pulsed Radio Frequency Energy on Wound Healing in Rats
    Gümüsay, M; Gülbagça, F; Saygili, S; Aydemir, I; Kaya, A; Tuglu, MI
    Delayed or not sufficiently good wound healing is a significant problem in medical treatment is needed to support in order to improve healing. Low frequency electromagnetic field (EMF) applications are seems to give this support. Disturbed vascularization, connective tissue formation, matrix exchange, and inflammation process in the wound environment are modified after EMF applications compared with control groups. Deteriorations in these factors which can be returned with the electrical impulses, DNA synthesis, transcription and transforms of protein synthesis, increasing of fibroblasts and endothelial cell proliferation indicate the presence of EMF mechanisms. Since the application and ambient conditions are kept constant but the type of the application has been changed in our study, it was provided that pulsed radio frequency energy (PRFE) is more effective and has more long-term improvement compared to pulsed electromagnetic fields (PEMF). The effects of these applications on cells and understanding of the mechanisms of the behavior will be much more significant and meaningful contribute to the treatment
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    Development of Electromagnetic Field System for Providing Wound Healing on Created Wound Model Rat Skin and Sensor Application
    Gümüsay, M; Gülbagça, F; Aydemir, I; Saygili, S; Kaya, A; Tuglu, MI
    Electromagnetic field (EMF) radiation are formed by the acceleration of electric charge. Electric charges produce electric and magnetic energy in space when they move. These waves have different frequencies and wavelengths and when they interact with an object they can be refracted, reflected or absorbed. When a suitable frequency and waveform EM signal is applied to the target tissue with the help of a coil or applicator physiological effects will occur at the cellular size. Today studies revealed significant molecular mechanisms occurring during wound healing. Nonionizing part of the EM spectrum is low-frequency electromagnetic fields are used as adjunct therapy in soft tissue injuries. In this study, the main goal is development of systems which will give better results compared with conventional treatment methods taking into account the effect on rat skin. To achieve this, some improvements in output power, increased gain, versatility, easy adjustments are provided for the spiral and planar antenna-applicator design.
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    Specific surface area effect on compressibility behaviour of clayey soils
    Yukselen-Aksoy, Y; Kaya, A
    In this study, the effect of specific surface area on compressibility and permeability characteristics of remoulded and intact clayey soils was investigated. Fifteen remoulded and 15 intact soils with a wide range of physicochemical properties were tested. The results indicate that specific surface area has a significant effect on compressibility and permeability behaviour of clayey soils. In addition to other soil index properties, specific surface area can be used for estimating these engineering properties. Significantly high correlation coefficient (r = 0.97) between compression index (C-c) and the specific surface area is observed for remoulded clayey soils with only methylene blue-spot specific surface area. There is no significant correlation between the BET-N-2 specific surface area and C-c: The effect of the remoulded water content on proposed specific surface area and C-c relationship is also investigated. The results show that as specific surface area of soils increases, c(v) decreases, indicating the importance of the diffuse double layer on the consolidation process. The results also reveal that permeability is controlled by the specific surface area of soils. In addition, the data obtained in this study indicate that there is a linear correlation between C-c/n(0) and C-c, which indicates the significance of initial void ratio on the compressibility characteristics of soils.
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    A study of factors affecting on the zeta potential of kaolinite and quartz powder
    Yukselen-Aksoy, Y; Kaya, A
    The purpose of this study was to determine the effects of pH, ion type (salt and metal cations), ionic strength, cation valence, hydrated ionic radius, and solid concentration on the zeta potential of kaolinite and quartz powder in the presence of NaCl, KCl, CaCl2, CuCl2, BaCl2, and AlCl3 solutions. The kaolinite and quartz powder have no isoelectric point (iep) within the entire pH range (3 < pH < 11). In the presence of hydrolysable metal ions, kaolinite and quartz powder have two ieps. As the cationic valence increases, the zeta potential of kaolinite and quartz powder becomes less negative. Monovalent cation, K+, yields more negative zeta potential values than the divalent cation Ba2+. As concentration of solid increases, the zeta potential of the minerals becomes more positive under acidic conditions; however, under alkaline conditions as solid concentration increases the zeta potential becomes more negative. Hydrated ionic radius also affects the zeta potential; the larger the ion, the thicker the layer and the more negative zeta potential for both kaolinite and quartz powder.
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    Synovial chondromatosis of the temporomandibular joint extending to temporalis, masticator, and parotid spaces
    Yildiz, ST; Demir, A; Kaya, A
    Synovial chondromatosis of the temporomandibular joint (TMJ) is very rare. We report a case of synovial chondromatosis of the TMJ with extraarticular extension that was diagnosed with MRI and CT. Histopathologic evaluation indicated that this case was synovial chondromatosis in intermediate phase.
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    Suitability of the methylene blue test for surface area, cation exchange capacity and swell potential determination of clayey soils
    Yukselen-Aksoy, Y; Kaya, A
    Application of the methylene blue test methods in determining soil properties, including specific surface area (SSA), cation exchange capacity (CEC), swell index, and swell potential are investigated on clayey soil samples with widely different mineralogy. The results indicate that the MB methods yield accurate prediction of some soil index properties, and they are easy to apply with simple test equipment. The results also show that the testing methods can be applied for soils that have widely different mineralogy. External and internal surface areas of soils can be measured by the MB adsorption methods. Effect of particle size on the MB surface area measurement accuracy was also studied using samples passing 0.425 mm (No. 40) and 0.075 mm (No. 200) sieves. The results show that there is no significant difference in the amount of absorbed methylene blue of the soil samples passing the No. 40 and No. 200 sieves. The test results also indicate that the MB-CEC values are generally lower than those obtained by the ammonium acetate method. The correlation coefficient between the MB-CEC and NH4-Na results is 0.88 indicating that MB can be used effectively to measure CEC of soils. The results also show that swell index and swell potential of the soils can be estimated with MB methods accurately, economically and readily. Significant relationship is observed between the swelling potential and MBV (methylene blue value) for a wide range of soils. A new classification for swelling soils is proposed using MBV. (C) 2008 Elsevier B.V. All rights reserved.
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    Method dependency of relationships between specific surface area and soil physicochemical properties
    Yukselen-Aksoy, Y; Kaya, A
    It is postulated that the behavior of fine-grained soils may be explained by the relationship between surface area and other geotechnical properties. To this end, there are several studies correlating geotechnical indexes with specific surface area (SSA). However, there is no universally accepted specific surface area determining method as several methods are available. Depending on the method employed, the measured specific surface area may show variations for a given soil. This is because the predictive power of each method depends on the type of minerals and organic matter that are present in the soil. Thus, different SSA determination methods yield widely different estimates of index properties and regression equations. To examine the role of method on SSA of soils, the SSAs of 32 soils with different mineralogies were determined using BET-N-2, EGME, MB-titration, and MB-spot test methods. The measured SSA of soils was correlated with their respective geotechnical index properties. Further, the data obtained in this study and those reported by previous researchers were compared. The results suggest that correlations between geotechnical index properties and SSA using different methods may not be comparable. Accurate prediction, however, is provided only if the relationship is calibrated using soils having similar physical and chemical characters. (c) 2010 Elsevier B.V. All rights reserved.
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    Predicting soil swelling behaviour from specific surface area
    Yukselen-Aksoy, Y; Kaya, A
    Some geotechnical index properties, such as the liquid limit, plasticity index, clay content and cation exchange capacity, have been used to predict the swelling potential of soils. However, a literature review indicates that prediction of the swelling potential of soils using these index properties is not completely successful. At the same time, the methods used to determine swelling potential are time-consuming. Thus researchers have been investigating other methods that can predict the swelling potential of soils readily and accurately. To this end, in this study the BET (Brunauer, Emmett and Teller equation)-N-2 adsorption, ethylene glycol monoethyl ether (EGME) and methylene blue (MB) measured specific surface areas (SSA) are correlated with the swell index and modified free swell index of soils. The SSA and swell index of 16 remoulded and 15 undisturbed soils consisting of a wide range of mineralogy were determined. Results indicate that the correlation between the SSA and the swelling behaviour of the clayey soils examined is significant. A linear relationship is observed between the swell index, C-s, and the MB SSA: the swell index of the soils increases as the SSA increases. The correlation coefficient between the SSA and the modified free swell index (MFSI) is 0.93, indicating that the MB SSA does exert a significant influence on the swelling behaviour of clayey soils. Based on the test results obtained, a new swelling potential classification is proposed.
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    Defeat, entrapment and suicidal ideation in a Turkish community sample of young adults: an examination of the Integrated Motivational-Volitional (IMV) model of suicidal behaviour
    Tuerk, N; Yasdiman, MB; Kaya, A
    The present study examines the relationships between defeat, entrapment, suicidal ideation, thwarted belongingness, and perceived burdensomeness through the Integrated Motivational-Volitional (IMV) Model of Suicidal Behaviour in a sample of Turkish young adults. The sample consisted of 451 individuals (72.5% females, Mage= 25.20). The correlation analyses revealed significant relationships between defeat, entrapment, suicidal ideation, thwarted belongingness, perceived burdensomeness in the expected directions. Mediation and moderation analyses partly confirmed the assumptions of the motivational phase of the IMV model; entrapment played a mediating role between defeat and suicidal ideation, and thwarted belongingness (but not perceived burdensomeness) had a moderating role in the pathway between entrapment and suicidal ideation. These findings add a new dimension to the understanding of suicide risk and potential protective factors through the IMV model, which was tested for the first time in the Turkish population. It is anticipated that this study will contribute to suicide prevention intervention strategies, especially for young adults, at-risk group for suicide in Turkey.
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    Impact of Obesity on the Metabolic Control of Type 2 Diabetes: Results of the Turkish Nationwide Survey of Glycemic and Other Metabolic Parameters of Patients with Diabetes Mellitus (TEMD Obesity Study)
    Sonmez, A; Yumuk, V; Haymana, C; Demirci, I; Barcin, C; Kiyici, S; Güldiken, S; Örük, G; Saydam, BO; Baldane, S; Kutlutürk, F; Küçükler, FK; Deyneli, O; Çetinarslan, B; Sabuncu, T; Bayram, F; Satman, I; Ayturk, S; Yilmaz, M; Asik, M; Dinccag, N; Cakmak, R; Turker, F; Idiz, C; Hacisahinogullari, H; Bagdemir, E; Yildiz, B; Haliloglu, O; Sancak, S; Ozsari, L; Cagiltay, E; Imre, E; Sait Gonen; Boysan, SN; Altuntas, Y; Ozturk, FY; Mert, M; Piskinpasa, H; Aydin, H; Imamoglu, S; Ersoy, C; Oz Gul, O; Selek, A; Dogru, T; Kirik, A; Kebapci, N; Efe, B; Kaya, A; Cordan, I; Kirac, CO; Capa, Z; Cesur, M; Yetkin, I; Corapcioglu, D; Canlar, S; Yildiz, OB; Sendur, SN; Cakir, B; Ozdemir, D; Corakci, A; Kutlu, M; Bascil Tutuncu, N; Bozkus, Y; Cakal, E; Demirbas, B; Ertek, S; Altay, M; Dagdeviren, M; Abedi, AH; Cetinkalp, S; Ozisik, H; Yener, S; Guney, E; Unubol, M; Yaylali, GF; Topsakal, S; Hekimsoy, Z; Akbaba, G; Aslan, I; Balci, MK; Dalkiran, S; Akbay, E; Gul, K; Agbaht, K; Yilmaz, MO; Bozkirli, E; Tetiker, BT; Cetinkaya Altuntas, S; Atmaca, A; Durmus, ET; Mete, T; Dikbas, O; Akin, S; Nuhoglu, I; Ersoz, HO; Bayraktaroglu, T; Sisman, P; Sahin, I; Cetin, S; Capoglu, I; Akbas, EM; Ucler, R; Eren, MA; Tuzcu, AK; Pekkolay, Z; Ozkaya, M; Araz, M; Salman, S; Dizdar, OS; Gurkan, E; Kargili Carlioglu, A
    Background: Obesity is the main obstacle for metabolic control in patients with type 2 diabetes. Turkey has the highest prevalence of obesity and type 2 diabetes in Europe. The effect of obesity on the metabolic control, and the macro-and microvascular complications of patients are not apparent. Objectives: This nationwide survey aimed to investigate the prevalence of overweight and obesity among patients with type 2 diabetes and to search for the impact of obesity on the metabolic control of these patients. We also investigated the independent associates of obesity in patients with type 2 diabetes. Methods: We consecutively enrolled patients who were under follow-up for at least 1 year in 69 tertiary healthcare units in 37 cities. The demographic, anthropometric, and clinical data including medications were recorded. Patients were excluded if they were pregnant, younger than 18 years, had decompensated liver disease, psychiatric disorders interfering with cognition or compliance, had bariatric surgery, or were undergoing renal replacement therapy. Results: Only 10% of patients with type 2 diabetes (n = 4,648) had normal body mass indexes (BMI), while the others were affected by overweight (31%) or obesity (59%). Women had a significantly higher prevalence of obesity (53.4 vs. 40%) and severe obesity (16.6 vs. 3.3%). Significant associations were present between high BMI levels and lower education levels, intake of insulin, antihypertensives and statins, poor metabolic control, or the presence of microvascular complications. Age, gender, level of education, smoking, and physical inactivity were the independent associates of obesity in patients with type 2 diabetes. Conclusion: The TEMD Obesity Study shows that obesity is a major determinant of the poor metabolic control in patients with type 2 diabetes. These results underline the importance of prevention and management of obesity to improve health care in patients with type 2 diabetes. Also, the results point out the independent sociodemographic and clinical associates of obesity, which should be the prior targets to overcome, in the national fight with obesity. (c) 2019 The Author(s) Published by S. Karger AG, Basel