Aydemir Çoban, E. | Şahin, Fikrettin

Book Part | 2018 | Advances in Experimental Medicine and Biology1089 , pp.97 - 113

Tumors consists of subpopulation of cells in which each subtype has contributes to tumor progression. Specifically one subtype known as cancer stem cells are associated with the initiation, progression, resistance to conventional therapies and metastasis. Metastasis is leading cause of cancer related deaths. Overall it is important to consider cancer as a whole in which a mutated cell proliferating indefinitely and forming its hierarchy consisting of subgroups with different molecular signatures. To be able to target this disease we need to evaluate every step including initiation, progression, survival, angiogenesis and finally mig . . .ration and repopulation. Cancer stem cells do play vital roles in each step however when metastasis can be stopped or eliminated we talk about saving a life or improving its quality. Considering how deeply these cancer stem like cells affect the tumor life and metastasis it is crucial to develop effective strategies against them. Metastatic cascade can also be directed by membrane derived vesicles specifically exosomes. Several studies show the role of exosomes in mediating cellular migration and pre-metastatic niche formation. During this chapter we wanted to explain in detail how the metastasis occur in tumor and how cancer stem cells contribute into the development of metastatic cascade and possibly suggest therapeutic approaches against cancer stem cells. © Springer Nature Switzerland AG 2018 Daha fazlası Daha az

Başoğlu, İ. | Hörmann, W. | Sak, H.

Article | 2018 | Annals of Operations Research260 ( 01.02.2020 ) , pp.113 - 128

We consider the problem of calculating tail loss probability and conditional excess for the Bernoulli mixture model of credit risk. This is an important problem as all credit risk models proposed in literature can be represented as Bernoulli mixture models. Thus, we deviate from the efficient simulation of credit risk literature in that we propose an efficient simulation algorithm for this general Bernoulli mixture model in contrast to previous works that focus on specific credit risk models like CreditRisk+ or Credit Metrics. The algorithm we propose is a combination of stratification, importance sampling based on cross-entropy, an . . .d inner replications using the geometric shortcut method. We evaluate the efficiency of our general method considering three different examples: CreditRisk+ and two of the latent variable models, the Gaussian and the t-copula model. Numerical results suggest that the proposed general algorithm is more efficient than the benchmark methods for these specific models. © 2016, Springer Science+Business Media New York Daha fazlası Daha az

Demirci, S. | Doğan, A. | Apdik, H. | Tuysuz, E.C. | Gulluoglu, S. | Bayrak, O.F. | Şahin, Fikrettin

Article | 2018 | Molecular and Cellular Biochemistry437 ( 01.02.2020 ) , pp.133 - 142

Cell proliferation and migration are crucial in many physiological processes including development, cancer, tissue repair, and wound healing. Cell migration is regulated by several signaling molecules. Identification of genes related to cell migration is required to understand molecular mechanism of non-healing chronic wounds which is a major concern in clinics. In the current study, the role of cytoglobin (CYGB) gene in fıbroblast cell migration and proliferation was described. L929 mouse fibroblast cells were transduced with lentiviral particles for CYGB and GFP, and analyzed for cell proliferation and migration ability. Fibroblas . . .t cells overexpressing CYGB displayed decreased cell proliferation, colony formation capacity, and cell migration. Phosphorylation levels of mTOR and two downstream effectors S6 and 4E-BP1 which take part in PI3K/AKT/mTOR signaling declined in CYGB-overexpressing cells. Microarray analysis indicated that CYGB overexpression leads to downregulation of cell proliferation, migration, and tumor growth associated genes in L929 cell line. This study demonstrated the role of CYGB in fibroblast cell motility and proliferation. CYGB could be a promising candidate for further studies as a potential target for diseases related to cell migration such as cancer and chronic wound treatment. © 2017, Springer Science+Business Media, LLC Daha fazlası Daha az

Kucukay, F. | Topcuoglu, O.M. | Alpar, A. | Altay, Ç.M. | Kucukay, M.B. | Ozbulbul, N.I.

Article | 2018 | CardioVascular and Interventional Radiology41 ( 2 ) , pp.225 - 230

Purpose: To investigate the safety, efficacy and long-term results of bronchial artery embolization with microsphere particles (Embosphere® Microspheres, BioSphere Medical, Rockland, MA) 700–900 µm in size for massive hemoptysis. Methods: One hundred and seventy-four patients (94 female, 80 male; mean age 39.4 ± 5.7) who had bronchial artery embolization for massive hemoptysis between January 2010 and October 2015 were incorporated in the study. Patients had hemoptysis with a mean volume of 525 ± 150 mL (median 500 mL, range 300–1200 mL) over a 24-h period. Underlying pathologies included bronchial artery hypertrophy due to bronchie . . .ctasis (56.3% [98/174]), lung cancer (29.9% [52/174]), tuberculosis (10.3% [18/174]) and the rest remained idiopathic (3.4% [6/174]). Mean bronchial artery diameter before the intervention was 3.8 ± 1.5 mm (median 4 mm, range 3.1–7.5 mm). Median follow-up period was 56 months (range 10–82 months). Primary objectives were the technical and clinical success. Results: Technical success was 100%. Clinical success for preventing massive hemoptysis was 91.9% (160/174). There was no procedure-related mortality or morbidities. Minor complications such as chest pain were observed in nine patients (5.0%). Recurrent hemoptysis (8.1%) was observed within 6 months in 14 patients, ten of whom were treated with a second embolization session and the remaining four with a total of three embolization sessions. Conclusion: Bronchial artery embolization for massive hemoptysis with Embosphere particles 700–900 µm in size is a safe and effective method with high technical and clinical success rates. Long-term results are excellent. © 2017, Springer Science+Business Media, LLC and the Cardiovascular and Interventional Radiological Society of Europe (CIRSE) Daha fazlası Daha az

Ercal, P. | Pekozer, G.G. | Kose, G.T.

Book Part | 2018 | Advances in Experimental Medicine and Biology1107 , pp.113 - 127

The treatment of bone that is impaired due to disease, trauma or tumor resection creates a challenge for both clinicians and researchers. Critical size bone defects are conventionally treated with autografts which are associated with risks such as donor site morbidity and limitations like donor shortage. Bone tissue engineering has become a promising area for the management of critical size bone defects by the employment of biocompatible materials and the discovery of novel stem cell sources. Mesenchymal stem cells (MSCs) can be isolated with ease from various dental tissues including dental pulp stem cells, stem cells from apical p . . .apilla, dental follicle stem cells, stem cells from human exfoliated deciduous teeth, periodontal ligament stem cells, gingival stem cells and tooth germ derived stem cells. Outcomes of dental MSC mediated bone tissue engineering is explored in various in vivo and in vitro preclinical studies. However, there are still obscurities regarding the mechanisms underlying in MSC mediated bone regeneration and challenges in applications of dental stem cells. In this review, we summarized dental stem cell sources and their characterizations, along with currently used biomaterials for cell delivery and future perspectives for dental MSCs in the field of bone tissue engineering. Further efforts are necessary before moving to clinical trials for future applications. © Springer International Publishing AG 2018 Daha fazlası Daha az

Taşlı, P.N. | Bozkurt, B.T. | Kırbaş, O.K. | Deniz-Hızlı, A.A. | Şahin, Fikrettin

Book Part | 2018 | Advances in Experimental Medicine and Biology1119 , pp.73 - 84

The use of Mesenchymal Stem Cells (MSCs) in the treatment of diseases where immunomodulation impacts therapy is increasing steadily. Recent studies aim to achieve effective use of MSCs in treatment of Graft versus Host Disease (GvHD), Crohn’s disease and organ transplantations. The molecular mechanisms governing immunomodulatory properties of MSCs have not been fully understood, although current studies are indicating progress. Especially, in vitro studies and animal models provide a major contribution to our knowledge in clinical use of MSCs. The immunosuppressive and immune-enhancer properties of MSCs are –typically- determined wi . . .th respect to type and concentrations of soluble molecules found in their physiological environment. In mammals the immune system protects the organism -not only- from certain microorganisms, but also from any entity that it recognizes as foreign, including its own cells when it is received as a threat. This protection can sometimes occur by increasing the number of immune cells and sometimes by suppressing a pathologically hyper-induced immunological response. In particular, realization of the bi-directional effect of MSCs on immune cells has placed substantial emphasis on this area of research. This chapter focuses on the interaction of MSCs with the immune cells, the bilateral role of these interactions, and whether studies that aim to understand these interactions can yield promising results in terms of developing improved use of MSCs in treatment. © Springer International Publishing AG, part of Springer Nature 2018 Daha fazlası Daha az

Kalemci, M. | Bağçe, A. | Ince, A.T. | Arifoviç, N.

Article | 2018 | International Journal of Thermophysics39 ( 9 ) , pp.73 - 84

The Temperature Laboratory at TUBITAK UME initiated a study which focused on the construction of freezing point cells of ITS-90 as primary temperature standards. The first cell constructed within the scope of this study was an open tin freezing point cell and the results were in good agreement with the reference tin fixed point cell of UME. The second set of cells constructed was two open zinc freezing point cells. The design of these cells is similar to the tin freezing point cell. After construction, all the home-made cells were evaluated by analyzing their melting and freezing curves. Finally comparison measurements were performe . . .d between the current laboratory reference zinc cell and all newly constructed cells. © 2018, Springer Science+Business Media, LLC, part of Springer Nature Daha fazlası Daha az

Oguz Aytekin, S. | Ince, R.

Article | 2018 | International Journal of Thermophysics39 ( 10 ) , pp.73 - 84

In this work, a Raman spectroscopic study of nanoporous silicon sensor samples demonstrated its use as a method of gauging the sensor potential via quantitative data it provides on the sensor nanostructure dimensions. This special property of the Raman spectroscopy technique also showed its potential to determine mechanical stability of the samples over 3 months. This work also shows that the Raman spectroscopy technique is sensitive to step changes in relative humidity in all the sensor samples via its measurement of the strain-free crystalline silicon (c-Si) Raman peak. Since the Raman technique is non-destructive and senses remot . . .ely on the fragile nanoporous sensor samples it will be the ideal replacement of the presently used electrical capacitance techniques as the primary determination of relative humidity. © 2018, Springer Science+Business Media, LLC, part of Springer Nature Daha fazlası Daha az

Abali Cetin, S. | Aslan, E.

Article | 2018 | Sexuality and Culture22 ( 3 ) , pp.881 - 893

Although several validated sexual satisfaction scales are globally relevant, none has demonstrated sufficient validity and reliability for use in Turkish populations, particularly women. This study aimed to assess the psychometric properties of the Sexual Satisfaction Scale for Women (SSS-W) in the Turkish version. A descriptive study was conducted involving 300 women. The scale’s validity and reliability were analyzed in two phases: phase I involved the translation and adaptation of the scale into Turkish and pilot testing; and phase II involved psychometric assessment. Content validity index was calculated and confirmatory factor . . .analysis was conducted to test the scale’s validity. To establish reliability we calculated Cronbach’s alpha, item-total and subscale-total correlations, and test–retest reliability that indicated time invariance. The scale’s content validity was reviewed by eight experts. Construct validity was established via confirmatory factor analysis; item factor loadings ranged.71–.93. Item-total score correlations ranged.49–.82; item-subscale score correlations ranged.58–.88; and subscale-total score correlations ranged.55–.92. Statistically significant correlations were found between each of these results (p Daha fazlası Daha az

Yucel, D. | Kocabas, F.

Book Part | 2018 | Advances in Experimental Medicine and Biology1079 , pp.103 - 125

Hematopoietic stem cells (HSCs) are rare cells, which housed in the adult bone marrow. They maintain all types of differentiated blood cells throughout life. Due to limited availability of HSCs for transplantation, treatment of various inherited bone marrow disorders and anemia requires the development of HSC expansion and gene editing technologies. To this end, various studies addressed the use of cytokines and growth factors for HSC expansion. Major hurdle with these studies was found to be spontaneous differentiation of HSCs into different lineages during ex vivo procedure. In addition, cost efficient approaches were needed. Thus . . ., studies move on to the identification of small molecules and development of RNA interference technologies with potential to enhance cell cycle progression and block inhibitory signaling mechanisms during ex vivo HSC expansion as well as single cell expansion of HSCs following gene editing studies. This review aims to highlight developments in hematopoietic stem cells expansion and gene editing technologies. © Springer International Publishing AG 2017 Daha fazlası Daha az

Kizilcik, N. | Koner, O.

Article | 2018 | Obesity Surgery28 ( 9 ) , pp.2783 - 2788

Objective: The purpose of the study was to investigate the effect of magnesium sulfate on pain management for pain after sleeve gastrectomy operation. Design: A prospective, randomized, placebo-controlled clinical study. Setting: University hospital. Participants: Eighty patients undergoing sleeve gastrectomy. Measurements and Main Results: Visual analog scale for the evaluation of pain, sedation score, mean arterial pressure, heart rate, and total analgesic consumption was recorded. Serum magnesium levels were determined before the operation, at the end of the operation, and at 24 h. There were no significant differences between th . . .e groups with respect to demographics, and sedation scores. Cumulative morphine consumption and pain scores were found to be higher in the control group than the magnesium group. Conclusion: Perioperative use of magnesium sulfate reduced postoperative pain and opioid consumption in obese patients undergoing sleeve gastrectomy operations. © 2018, Springer Science+Business Media, LLC, part of Springer Nature Daha fazlası Daha az

Arbatlı, S. | Aslan, G.S. | Kocabaş, F.

Book Part | 2018 | Advances in Experimental Medicine and Biology1079 , pp.37 - 53

The common prevalence of heart failure and limitations in its treatment are leading cause of attention and interest towards the induction of cardiac regeneration with novel approaches. Recent studies provide growing evidence regarding bona fide cardiac regeneration post genetic manipulations, administration of stimulatory factors and myocardial injuries in animal models and human studies. To this end, stem cells of different sources have been tested to treat heart failure for the development of cellular therapies. Endogenous and exogenous stem cells sources used in regenerative cardiology have provided a proof of concept and applica . . .bility of cellular therapies in myocardial improvement. Recent clinical studies, especially, based on the endogenous cardiac progenitor and stem cells highlighted the possibility to regenerate lost cardiomyocytes in the myocardium. This review discusses emerging concepts in cardiac stem cell therapy, their sources and route of administration, and plausibility of de novo cardiomyocyte formation. © Springer International Publishing AG 2017 Daha fazlası Daha az