İstanbul Sağlık ve Teknoloji Üniversitesi Kurumsal Akademik Arşivi
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A pioneer Turkish urologist-medical historian (Saim Erkun 1901–1949) and his one-century-old review about prostate
No full textSaim Erkun (1901–1949) was born in Manisa at Aegean region of Anatolia as an Ottoman citizen. While his early life was spent in late Ottoman times at military actions including military prison camp in British colony; India, his active professional productive period was in early Turkish republic period (Est. 1923, centenary). He had a good education period for medicine with the help of his good level of all main World scientific languages such as French, German, and English. Besides his main profession, he was also interested in Ottoman urological medicine around the conquer of Istanbul and allocated them a space in his books in 1930s. He was one of the earliest urology resident (1929–1933, Istanbul) of modern medicine in Turkey. He performed many urological procedures and published the outcomes following modern scientific algorithms, furthermore, there have been urological books including “history” partly referring to antique Ottoman literature among his publications. In this manuscript we focused on the magic word of Urology forever; “Prostate,” among his essays. Turkish medicine, particularly urology, renewed itself by some intelligent hard working young clinicians such as Saim Erkun, immediately after the short struggling by means of establishment process of modern Turkiye after World War I by the collapsing of old Ottoman Empire. Furthermore, we think that the stunning special word of urology, “prostate,” should especially be mentioned to emphasize the importance of this beginning
Shaping ability of novel nickel-titanium rotary ınstruments manufactured with different thermal treatments
No full textGİRİŞ ve AMAÇ: Bu çalışmanın amacı farklı termomekanik teknolojiler kullanılarak üretilmiş 4 adet Nikel-titanyum esaslı döner alet sisteminin; ProTaper NEXT (Dentsply Maillefer, Ballaigues, İsviçre), BT-RaCe (FKG, La Chaux-de-Fonds, İsviçre), K3XF (SybronEndo, West Collins, Kaliforniya, ABD) ve HyFlex CM (Coltène-Whaledent, Altstatten, İsviçre), şekillendirme etkinliklerini karşılaştırmaktır. YÖNTEM ve GEREÇLER: S-şekilli kanal içeren reçine bloklardan (n=20) işlem öncesi ve sonrası dijital fotoğraflar; ileri derecede eğimli kanala sahip çekilmiş dişlerden (n=20) şekillendirme öncesi ve sonrası standart yöntemle dijital radyografiler alınmıştır. Alınan fotoğraf ve radyografiler bilgisayar yazılım programı yardımı ile çakıştırılarak ölçümler yapılmış ve transportasyon miktarı ile merkezde kalma oranları hesaplanmıştır. İstatistiksel değerlendirmede varyans analizi ve Kruskal Wallis testi ve post-hoc Tukey ve Dunn’s çoklu karşılaştırma testleri kullanılmıştır. Sonuçlar anlamlılık p0,05). BT-RaCe sistemi her iki eğimde de en fazla transportasyon oluşturan (p<0,05) sistem olmuştur. Çekilmiş dişlerde, en az transportasyonu K3XF ve HyFlex CM sistemleri oluşturmuştur (p<0,05). Çalışma uzunluğunda en fazla transportasyona BT-RaCe sistemi neden olmuştur. ProTaper NEXT sisteminin kanal düzleşmesi meydana getirdiği saptanmıştır. TARTIŞMA ve SONUÇ: İleri derecede eğimli ve birden fazla eğime sahip kök kanalların şekillendirilmesinde K3XF en uygun sistem gibi görünmektedir. HyFlex CM sisteminin de güvenle kullanılabileceği sonucuna varılmıştır. Esnekliği arttırılmış alaşımlardan üretilen aletlerin zorlu vakaların şekillendirilmesinde daha başarılı sonuçlar verdiği gözlemlenmiştir.INTRODUCTION: To compare the shaping efficacy of 4 rotary instrumentation systems (ProTaper NEXT (Dentsply Maillefer, Ballaigues, Switzerland), BT-RaCe (FKG, La Chaux-de-Fonds, Switzerland), K3XF (SybronEndo, West Collins, CA, USA) ve HyFlex CM (Coltène-Whaledent, Altstatten, Switzerland) manufactured with different processing technologies of nickel-titanium wire. METHODS: Superimposed pre- and postoperative images of simulated S-shaped canals (n=20) and digital radiographs of severely curved root canals (n=20) were used to determine amount of transportation and centering ratio. The data were analyzed using analysis of variance and Kruskal Wallis test and post-hoc Tukey and Dunn’s multiple comparison tests and significance was set at P<0.05. RESULTS: In simulated S-shaped canals, K3XF gave the best results with respect to amount of transportation and centering ratio at the coronal curvature (P<0.05) followed by HyFlex CM and ProTaper NEXT with no significant differences between them. At the apical curvature, K3XF and HyFlex CM presented significantly better centering ratio results than ProTaper NEXT (P<0.05). BT-RaCe showed significantly higher transportation values than the other systems in both curvatures (P<0.05) In extracted teeth, K3XF and HyFlex CM resulted in the least mean canal transportation (P<0.05) BT-RaCe produced the highest amount of transportation at the apical end point of instrumentation. ProTaper NEXT exhibited pronounced canal straightening. DISCUSSION AND CONCLUSION: Under the conditions of this study, K3XF appears to be more suitable to shape multi-curved and severely curved root canals. HyFlex CM showed adequate canal preparation and was also safe. Alloy types with greater flexibility seem to result in better shaping outcome in complex canals
Energy, exergy, exergoenvironmental, and exergoenviroeconomic assessment of a two stroke UAV small engine using JP5 aviation fuel and hydroxy (HHO) gas
No full textHydroxy gas (HHO) is a gas produced by the electrolysis of water, which involves breaking down water molecules (H2O) into hydrogen (H2) and oxygen (O2) gases. When the electricity used for electrolysis comes from renewable energy sources, the resulting hydrogen can be classified as 'green hydrogen.' Therefore, by using renewable green energy sources to produce HHO gas, its application in internal combustion engines can promote clean combustion and enhance sustainability. This study explores the enhancement of performance and emission characteristics in a two-stroke Unmanned Aerial Vehicle (UAV) engine using Hydroxy gas (HHO), a green energy source produced via water electrolysis. The primary objective is to improve engine efficiency and reduce environmental impacts by employing HHO in dual-fuel mode with JP5 aviation fuel. Addressing a clear research gap in the literature, this study is the first to evaluate the energy, exergy, exergoenvironmental, and exergoeconomic aspects of a two-stroke, air-cooled UAV engine using the JP5+HHO fuel blend. Experiments were conducted at five shaft speeds (3250, 3750, 4500, 5250, 6250 rpm) and four HHO flow rates (1.0, 1.5, 2.0, 4.0 lpm). The results demonstrate that incorporating HHO gas leads to a significant improvement in engine performance, with a 10% average reduction in Brake Specific Fuel Consumption (BSFC) and a 10% increase in exergy efficiency. Additionally, the JP5+HHO 4 lpm mixture reduces exergy destruction by approximately 10% and increases heat transfer exergy by 3–10%. On the environmental front, while HHO slightly increases CO2 emissions, the exergoenvironmental impact rises by a manageable 4%. Importantly, the high HHO flow rate (4 lpm) achieves a 2% average reduction in both exergoenvironmental and exergoeconomic impacts. These findings underscore the potential of HHO as a sustainable fuel source, offering both performance gains and reduced environmental and economic costs
Pd(II) and Pt(II) saccharinate complexes with two phosphine derivatives: Synthesis, anticancer and antiangiogenic activities
No full textAs clinically used anticancer Pt(II) drugs have severe side effects, there is a growing interest for new metal complexes with great potential for cancer therapy. The current work aimed to prepare and characterize new Pd(II) and Pt(II) saccharinate (sac) complexes bearing pyridyl- and benzyldiphenylphosphines (PPh2Py and PPh2Bz, respectively), cis-[Pd(sac)2(PPh2Py)2] (1), cis-[PtCl(sac)(PPh2Py)2]·0.5DMF (2), cis-[Pd(sac)2(PPh2Bz)2]·DMF (3) and trans-[PtCl(sac)(PPh2Bz)2] (4) as promising anticancer and antiangiogenic drugs. The anticancer activity of the complexes was screened against seven cancer cell lines including HCT116 (colon), HepG2 (liver), MDA-MB-231 (breast), PANC-1 (pancreatic), A549 (lung), C6 (glioma), DU145 (prostate) and normal human lung epithelial cells (BEAS-2B). 1 and 2 did not show biological activity below 20 μM at 48 h, whereas 3 and 4 displayed significant cytotoxic effect on the cancer cells. 4 was the most potent complex (IC50 = 2.2–12.1 μM) and displayed much greater cytotoxicity than cisplatin in all the cancer cell lines. 4 caused apoptosis in HCT116 cells as evidenced by annexin V positivity and caspase 3/7 activity assays. Furthermore, the inhibition of antiapoptotic Bcl-2 proteins by the complex suggested the intrinsic apoptosis. In addition, 4 greatly enhanced generation of intracellular reactive oxygen species (ROS) and consequently caused remarkable DNA double-strand breaks in HCT116 cells. Moreover, the chick chorioallantoic membrane (CAM) assay was used to evaluate antiangiogenic potential of 4. The complex effectively inhibited angiogenesis at a dose of 50 ng, suggesting it as a promising multi-targeted agent for antiangiogenic cancer treatment
Nutritional analysis of vegan recipes: From social media to plate
No full textThe study aimed to determine the nutritional composition of vegan recipes shared on the Instagram social media platform and to compare these ingredients with their non-vegan/omnivorous versions. Turkish and English vegan recipes of meatballs (n = 53), burgers (n = 12), pizza (n = 15), pasta (n = 38), cake (n = 58), and cookies (n = 52) were obtained from Instagram. They all met the criteria of being shared as #vegan labeled, presented detailed information about ingredients, and only included plant-based ingredients. Afterward, non-vegan/omnivorous recipes (n = 228) were determined as equivalent to the vegan recipes in each food group, and a total of 456 recipes were evaluated. The amounts of macro- and micronutrients per 100-gram serving were obtained by the Nutritional Data System (BeBiS). According to the outcomes, the most significant differences in nutritional composition were found between vegan and non-vegan meatball recipes. The levels of cholesterol and B12 were significantly lower in English vegan recipes of meatballs, pasta, cake, and cookies compared to their non-vegan versions (p < .05). Consuming different vegan foods throughout the day could provide complementary nutrient intake and sustainable optimal health. Nevertheless, recipe-based updates could be an innovative approach in future vegan studies. In addition, analysis of vegan recipes could be considered to modulate vegan supplementation programs
Antibiotic adjuvant activities of quorum sensing signal molecules DSF and BDSF against mature biofilms of Staphylococci
No full textAmong promising antibiofilm compounds, quorum-sensing (QS) molecules that regulate biological processes such as biofilm formation and intra- or interspecies communication appear to be good candidates. The invitro antibiotic-adjuvant effects of QS molecules diffusible signal factor (DSF) and B. cenocepacia producing-DSF (BDSF) were investigated against mature Staphylococcal biofilms. Broth microdilution methods were used for the determinations of MIC, MBC, MBIC, and MBEC, and bactericidal activities were determined by TKC method. The lowest MICs were obtained with ciprofloxacin and gentamicin, and MBECs with ciprofloxacin. DSF and BDSF at 0.5 µM decreased the MICs as 2–8, and 2–32 fold, respectively. In TKC studies, –cidal activities were achieved by BDSF + gentamycin, or ciprofloxacin, and DSF + daptomycin, vancomycin, meropenem or gentamycin combinations. Synergistic effects were generally obtained with BDSF + gentamicin combinations, followed by DSF + daptomycin against most S. aureus; while BDSF + gentamicin or ciprofloxacin, and DSF + vancomycin or meropenem were synergist against some S. epidermidis biofilms. Also, the antagonist effects were observed with BDSF + meropenem or ciprofloxacin against each MSSE and MSSA. It is estimated that these QS molecules, although it was strain dependent, generally enhanced the antibiotic activity, and would be a new and effective treatment strategy for biofilm control, either alone or as an antibiotic adjuvant.Istanbul University -- 5440
Electrochemical aptamer-based biosensors for disease biomarkers
No full textThe increasing prevalence of diseases such as neurodegenerative conditions, cardiovascular dis orders, and cancer represents a significant public health challenge. Timely diagnosis plays a crucial role in improving patient outcomes and alleviating the overall societal burden posed by these disorders. Recently, there has been increasing interest in using electrochemical aptasensors in diagnosing and prognosis neurodegenerative diseases, cardiovascular disorders and cancer. This comprehensive review categorizes and examines the latest advances in electrochemical aptasen sors for evaluating these diseases. The aptasensors under investigation target specific analytes appropriate for each disease group. For cardiovascular diseases, analytes such as Cardiac troponins (cTns), myoglobin (Mb), C-reactive protein (CRP), creatine kinase-MB (CK-MB) and B-type natriuretic peptide (BNP) have been in focus. AβO, Tau, Prion protein and Alpha-synuclein (α-synuclein) were examined in neurodegenerative diseases. Carcinoembryonic antigen (CEA) and Prostate-specific antigen (PSA) biomarkers are of particular interest in the context of cancer. The review includes a comprehensive analysis of the development of these aptasensors over the last 5 years under three main headings, taking into account the advantages and disadvantages of these diagnostic tools and issues such as linear ranges, detection limits and preferred nanomaterials. In addition, this review focuses on an overview of the current problems and achievable solutions of aptasensors in detecting common diseases, and future trends are also predicted
Material selection for artificial femur bone using PROMETHEE-GAIA method
No full textWhen replacing bones and implants, choosing the right materials for the artificial bone and orthopedic implants is crucial to the procedure’s success. In this work, a thorough assessment of the literature was followed by a thorough and rigorous evaluation of prospective materials for prosthetic femurs using a multicriteria decision-making process known as PROMETHEE-GAIA (Preference Ranking Organization METHod for Enrichment Evaluation and Geometric Analysis for Interactive Assistance). The proposed approach was validated using a total of 12 assessment parameters, including density, tensile strength, and ultimate tensile strength, and 17 candidate materials. The significance of the chosen criteria is well described. These 17 candidate implant materials and the 12 assessment criteria were used to develop a choice matrix. Rankings over the prepared matrix were produced using the PROMETHEE-GAIA program. Ti-6Al-7Nb, Ti-6Al-4V, and ASTM F1537, Standard Specification for Wrought Cobalt-28Chromium-6Molybdenum Alloys for Surgical Implants (UNS R31537, UNS R31538, and UNS R31539), Co-Cr-W emerged as the top contenders and were demonstrated as possible materials for effective artificial femur materials because of the assessment. With a large number of pertinent criteria and a wide range of materials, this study offers a framework for the selection of implant materials. It also emphasizes how choosing materials carefully may increase the durability and efficiency of orthopedic implants
The image of the Turk and oriental discourse in panait istrati’s Kyra Kyralina and Ivo Andrić’s the bridge on the drina
No full textIn its historical context, the image of the Turk—which presents itself along with the histories, memories and stories throughout Central Europe as well as the Balkans— evolved significantly, owing much to the fact that these regions were and still are inhabited by people of various ethnicities, religions, and cultural structures, and were often focal points of crucial political changes and social developments, including the emergence of the Muslim population amongst the native Orthodox population of the Balkans. Kyra Kyralina and The Bridge on the Drina are works that focus on the condi tion of the Balkans, a region ruled by numerous empires, while using the both histori cal and mythological image of the Turk. This chapter aims to analyze and criticize the stories and memories in these works, specifically in the light of Andre Gingrich’s theory of frontier Orientalism, which largely focuses on the Orientalism observed and understood by the people who are/ were members of the nations placed between and on the borders of the Occident and the Orient. Additionally, this chapter will compare and contrast the different perspec tives on and ideas of the image of the Turk in the novels while analyzing the frontier condition represented by the themes and characters of the works. This image (and the differences between its variations) is emphasized and underlined within the scope of Joep Leerssen’s Imagology and MacMillan’s Images of the Turk in Europe. As is the case with most cultural images, the image of the Turk varies significantly, both in Kyra Kyralina and The Bridge on the Drina
Efficient removal of estrone and 17β‑estradiol from aqueous medium using UV irradiation‑assisted fenton process
No full textThe endocrine-disrupting compounds (EDCs) have high-risk implications for public health and the environment due to their potential to interfere with endocrine system functions. This study is based on an evaluation of the applying the UV-assisted Fenton process for the removal and degradation of 17β-estradiol and estrone in aqueous medium. The simple and affordable UV irradiation system was developed and applied to accelerate the Fenton reaction. High performance liquid chromatography (HPLC) was employed for the quantitative measurements of estrogenic hormones at 230 nm, which is highly sensitive and capable of accurately measuring hormones within 15 min. The LOD/LOQ values of HPLC system were recorded to be 0.03/0.11 mg/kg and 0.05 /0.15 mg/kg for estrone and 17β-estradiol, respectively. Fe3O4 magnetic nanoparticles and iron (II) sulfate solution were evaluated as appropriate iron sources under fixed UV irradiation to assess the Fenton process. The main parameters, namely hydrogen peroxide (H2O2) amount, iron (II) sulfate amount, pH, and UV irradiation period, were optimized univariately for determining the optimum conditions. The optimum conditions were recorded to be: 0.70 mL of pH 3.0 buffer solution, 1.25 mL of H2O2, 0.80 mL of 100 mg/L Fe2+ solution, and an irradiation time of 60 min. The removal experiments were also carried out on domestic wastewater to validate the system’s applicability. The percent removal efficiencies of both estrogenic hormones were calculated at higher than 99%. These results showed that high efficiency was achieved within the detection limits of the HPLC system. This proves the possibility of complete degradation of the analytes and their efficiency and practicality for pollution control and water quality improvement in future studies