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8. Discovery of Plastics-degrading Enzymes

Author

Mervan Çakar, Mehmet, Vuković Domanovac, Marija, Findrik Blažević, Zvjezdana, Mervan Çakar, Mehmet, Vuković Domanovac, Marija, and Findrik Blažević, Zvjezdana

Abstract

Plastics are highly advanced materials that have a vast array of applications and are produced globally in an approximate amount of 350 to 400 million tons every year. Nevertheless, there are serious concerns about plastic waste and pollution as a result of the misuse and lack of control of their use in industries, including packaging, transportation, manufacturing, and agriculture. Approximately 1,000 years are required for plastic bags to decompose efficiently. Additionally, CO2 and dioxins are released into the atmosphere by burning plastics, and they contribute to global warming. The Earth’s environment is overwhelmed with waste, mostly from poor recycling practices and low circular usage, resulting in millions of tons of waste generated annually. To combat this, new technologies for recycling post-consumer plastics are desperately needed to decrease plastic waste and improve the environment, while also finding ways to utilise these materials. Due to the inadequate disposal methods currently available for plastic waste, there has been increased interest in the use of microorganisms and enzymes designed for the biodegradation of non-degradable synthetic polymers via biocatalytic depolymerisation indicating that plastics treatment and recycling can be more efficient and sustainable., Plastika je daleko najnapredniji materijal kad je riječ o primjeni i svojstvima, a procjenjuje se da se svake godine globalno proizvede 350 do 400 milijuna tona. Ona je postala ozbiljan problem s obzirom na odlaganje plastičnog otpada i onečišćenje, zbog njezine nekontrolirane upotrebe u različite svrhe tijekom posljednjih desetljeća, kao što su pakiranje, transport, industrija i poljoprivreda. Za učinkovitu razgradnju plastičnih vrećica potrebno je otprilike 1000 godina. Osim toga, izgaranjem plastike u atmosferu se ispuštaju CO2 i dioksini koji doprinose globalnom zatopljenju. Zemaljski kopneni ili morski okoliš akumulira milijune tona otpada svake godine zbog lošeg recikliranja i niske kružne upotrebe. Inovativne tehnologije za recikliranje otpadne plastike prijeko su potrebne za smanjenje plastičnog otpada i postizanje ciljeva kvalitete okoliša uz valorizaciju potrošne plastike. Zbog trenutačno neadekvatnih metoda zbrinjavanja plastičnog otpada povećan je fokus na upotrebu mikroorganizama i enzima dizajniranih za biorazgradnju nerazgradivih sintetičkih polimera putem biokatalitičke depolimerizacije, što ukazuje na to da obrada plastike i recikliranje mogu biti učinkovitiji i održivi.

Published
2023

10. Slatke tajne enzima

Author

Milčić, Nevena, Sudar, Martina, Findrik Blažević, Zvjezdana, Bošnjak, Ivana, Çakar, Mehmet Mervan, Leaković, Emerik, Mateša, Lorena, Skendrović, Dino, Bolješić, Leo, Kos, Krešimir, and Petrić, Ivana

Subjects
enzimi, primjena enzima, razgradnja šećera
Abstract

Na ovoj radionici upoznat ćemo sudionike s dva enzima koji su vrlo zastupljeni u prehrambenoj industriji, a funkcija im je razgradnja kompleksnih šećera na one jednostavnije. U prvoj aktivnosti će se koristiti enzim laktaza za razgradnju laktoze u mlijeku na glukozu te galaktozu te određivati sadržaj nastale glukoze. U drugoj aktivnosti će se pratiti bistrenje voćnog soka te promjene na kriškama voća koje nastaju uslijed djelovanja enzima pektinaze.

Published
2023

15. Türkiye’de Tüketicilere Yönelik Uzaktan Programlanabilir SIM Ekosistemi

Author

ÇAKAR, Mehmet Akif

Subjects
Computer Science, Information System, e-SIM,gömülü-SIM,SM-DP+,SM-DS,LPA, e-SIM,embedded-SIM,SM-DP+,SM-DS,LPA, Bilgisayar Bilimleri, Bilgi Sistemleri
Abstract

Tüketicilere yönelik Uzaktan Programlanabilir SIM (e-SIM) standartları GSMA tarafından belirlenmektedir . 12.02.2019 tarihinde yayınlanan Bilgi Teknolojileri ve İletişim Kurulu kararında e-SIM teknolojilerinin Türkiye’de tabi olacağı mevzuat şekillenmiştir. Bu çalışmada son kullanıcıya yönelik e-SIM ekosisteminin temel bileşenlerinden SM-DP+, SM-DS ve LPA’a ait teknik detaylar, uluslararası standartlar ve yerel mevzuat ışığında ele alınmıştır. Tespit edilen olası problemlere yönelik çözüm önerileri sonuç bölümünde ele alınmıştır., The e-Sim requirements for the end user (Consumer) are defined by GSMA. Information Technology and Communications Committee of Turkey has published local legislation about e-SIM requirements on 02.12.2019. In this study, the technical details of SM-DP+, SM-DS and LPA, which are the main components of the e-Sim ecosystem for the end user, have been handled within the framework of international standards and local legislation. Solution suggestions for possible problems identified are discussed in the results section.

Published
2021

16. Understanding women's provider choice for induced abortion in Turkey

Author

Çakar, Mehmet, Pekkurnaz, Didem, Ökem, Zeynep Güldem, Çakar, Mehmet, Pekkurnaz, Didem, and Ökem, Zeynep Güldem

Abstract

In Turkey, women gained free access to induced abortion from public facilities through the legalization of abortion in 1983. However, due to unmet need and abortion stigma, women use predominantly private services. The political discourse on anti-abortion in the past decade has triggered a diminishing trend in public provision. This runs against both the 1983 Law and the healthcare reforms initiated in 2003, which aimed at universal access to health services. This study investigates the socioeconomic characteristics of women affecting the utilization of public services for induced abortion. Using Turkey Demographic and Health Survey 2013, the results of Probit models indicate that women who were young, unmarried, wealthier and whose abortion decisions were made by themselves or their spouses were less likely to choose the public services for induced abortion. Regional differences in the utilization of public sector were also observed. Findings indicate a need to ensure and widen women's access to abortion nationwide; both at the hospital and outpatient level. Health education programs including family planning should give special emphasis to young, single and socioeconomically disadvantaged women who are more prone to apply for unsafe abortion when access to public and/or private sector is limited. A transparent referral system should be designed to timely direct women to abortion services. 0 2021 Elsevier B.V. All rights reserved.

Published
2022

17. Clinical characteristics and prognostic factors of patients with COVID-19

Author

KARABAY, Oğuz, primary, AYDIN, Abdülkadir, additional, ÖĞÜTLÜ, Aziz, additional, YAYLACI, Selçuk, additional, DHEİR, Hamad, additional, GÜÇLÜ, Ertuğrul, additional, YILMAZ, Emel, additional, TOPTAN, Hande, additional, KÖROĞLU, Mehmet, additional, GÜNEYSU, Fatih, additional, GENÇ, Ahmed Bilal, additional, ÖZMEN SÜNER, Kezban, additional, KOCAYİGİT, Havva, additional, KARABAY, Meltem, additional, FUAT, Ali, additional, EKERBİÇER, Hasan, additional, AYDEMİR, Yusuf, additional, YURUMEZ, Yusuf, additional, TOMAK, Yakup, additional, GÜNDÜZ, Yasemin, additional, ÖZTÜRK, Mehmet Halil, additional, and ÇAKAR, Mehmet Akif, additional

Published
2022
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20. Clinical Characteristics and Prognostic Factors of Patients with COVID-19

Author

KARABAY, Oğuz, AYDIN, Abdülkadir, ÖĞÜTLÜ, Aziz, YAYLACI, Selçuk, DHEİR, Hamad, GÜÇLÜ, Ertuğrul, YILMAZ, Emel, TOPTAN, Hande, KÖROĞLU, Mehmet, GÜNEYSU, Fatih, GENÇ, Ahmed Bilal, ÖZMEN SÜNER, Kezban, KOCAYİGİT, Havva, KARABAY, Meltem, FUAT, Ali, EKERBİÇER, Hasan, AYDEMİR, Yusuf, YURUMEZ, Yusuf, TOMAK, Yakup, GÜNDÜZ, Yasemin, ÖZTÜRK, Mehmet Halil, and ÇAKAR, Mehmet Akif

Subjects
COVID-19, Mortalite, Prognoz, Health Care Sciences and Services, Sağlık Bilimleri ve Hizmetleri, Mortality, Prognosis
Abstract

Objective: We aimed to determine the main demographic features of COVID-19, reveal the clinical differences to patients in other countries, evaluate severe adverse effects in terms of number and types of comorbidities, and provide information about prognosis possibilities.Materials and Methods: Patients’ records, followed at Sakarya University Hospital between late March 2020 and late April 2020 with a diagnosis of COVID-19, were evaluated for this study. Demographic features were noted retrospectively with records, and data were recorded in the MS Excel program for analysis with SPSS. Statistical significance was set at p < 0.05.Results: The records of 1443 cases, 704 (48.8%) women and 739 (51.2%) men, a mean age of 44.98 ± 18.72, were examined retrospectively. Among them, 9.9% were medical staff, 1.8% had a history of travel abroad, and 1.1% were pregnant. Radiological findings of 59.4% of our polymerase chain reaction (PCR) positive patients were compatible with COVID. The mean length of hospital stay was 4.5 days. Frequent comorbidities were hypertension, diabetes (DM), and ischemic heart disease. Eighty (5.5%) patients treated in intensive care (ICU) died.Conclusion: Based on the data of 1443 patients, the mean length of hospitalization of COVID-19 patients was 4.5 days, or followed up in intensive care, having DM and a long period of hospitalization, which increased mortality risk. None of the outpatients died., Amaç: COVID-19 için başlıca demografik özelliklerin belirlenmesini, diğer ülkelerdeki hastalara göre klinik farkları ortaya koymayı, ciddi yan etki riskinin komorbidite sayısı ve tipine göre değerlendirilmeyi ve olası prognozla ilgili bilgileri ortaya çıkarmayı amaçladık.Gereç ve Yöntemler: Bu araştırma Sakarya Üniversitesi hastanesinde 27 Mart 2020- 27 Nisan 2020 tarihleri arasında COVID-19 enfeksiyonu tanısıyla izlenen hastaların kayıtlarından elde edilmiştir. Hastalara ait demografik özellikler hasta kayıtlarından retrospektif olarak elde edilmiş, elde edilen veriler MS Excell programına kayıt edilmiştir. Elde edilen veriler SPSS programıyla analiz edilerek karşılaştırılmış ve p

Published
2021

23. Paraoxonase1, Arylesterase and Total Thiol Investigation in Angiography Patient Plasmas

Author

YAZAR, Hayrullah, KUŞÇU GÜNAY, Güler, İNCİ, Mustafa Baran, KALELİ, Süleyman, and ÇAKAR, Mehmet

Subjects
Arylesterase,paraoxonase 1,renal anjiyografi,total tiyol, Health Care Sciences and Services, Arylesterase,paraoxonase 1,renal angiography,total thiol, Sağlık Bilimleri ve Hizmetleri
Abstract

Amaç: Radyal koroner anjiyografi uygulanan erişkin hastalarda; Paraoxonase-1 (PON 1), Arilesteraz (ARE) ve Total tiyol (TTL) değerlerinin, kan plazmasında tespit edilmesi amaçlandı. Materyal ve Metot: Çalışmanın katılımcı sayısı, birisi kontrol diğeri hasta grubu olmak üzere, iki grupta toplam 68 oldu. Kontrol grubu 34 sağlıklı bireyden oluşurken, hasta gurubu ise 34 radyal koroner anjiyografi hastasından oluştu. Kan numuneleri lityum heparinli tüplere alındıktan sonra laboratuvara transfer edildi ve burada santrifüj işleminden sonra ayrılan plazmaları, çalışma gününe kadar kapaklı ependorf tüplerde -80C0 de saklandı. Test parametreleri tam otomatik analizörde spektrofotometrik metot ile incelendi. Çalışmada elde edilen veriler SPSS 23 paket programı ile istatistiksel olarak analiz edildi. Anlamlılık düzeyi, p, Objective: In adult patients undergoing radial coronary angiography; It was aimed to determine the values ​​of paraoxonase-1, Arylesterase and Total thiol in blood plasma. Materials and Methods: The number of participants in the study was 68 in two groups, one for the control group and the other for the patient group. While the control group consisted of 34 healthy individuals, the patient group consisted of 34 radial coronary angiography patients. After blood samples were taken into lithium heparin tubes, they were transferred to the laboratory and the plasma separated after centrifugation was stored at -80 °C in capped eppendorf tubes until the working day. Test parameters were analyzed by spectrophotometry method on a fully automated analyzer. The data obtained in the study were statistically analyzed with the SPSS 23 package program. Significance level was accepted as p

Published
2021

24. MACHINE-TO-MACHINE E-SIM ECOSYSTEM IN TURKEY

Author

ÇAKAR, Mehmet Akif

Subjects
e-SIM,gömülü-SIM,SM-DP,SM-SR, e-SIM,embedded-SIM,SM-DP,SM-SR
Abstract

Makineler arası ağlara yönelik Uzaktan Programlanabilir gömülü SIM (e-SIM) standartları GSMA tarafından belirlenmektedir (GSMA, 2018). İlk kararlı e-SIM standardının GSMA tarafından 2016 yılında yayımlanmasının ardından 12.02.2019 tarihinde Bilgi Teknolojileri ve İletişim Kurulu tarafından e-SIM teknolojilerinin Türkiye’de tabi olacağı mevzuat belirlenmiştir. GSMA tarafından tanımlanan e-SIM ekosistemi; tüketicilere yönelik ve makineler arası ağlara yönelik olmak üzere ikiye ayrılmaktadır. Bu çalışmada makineler arası ağlara yönelik e-SIM ekosistemi ele alınmış olup tüketicilere yönelik e-SIM ekosistemi çalışma kapsamının dışında tutulmuştur. Makineler arası ağlara (M2M) yönelik e-SIM ekosisteminin temel bileşenleri; mobil ağ operatörleri, veri hazırlama hizmeti, güvenli yönlendirme hizmeti, gömülü evrensel entegre devre kartı barındıran e-SIM uyumlu cihazlar, üreticiler ve sertifika otoritesidir. Çalışma içerisinde ekosisteminin temel bileşenlerinden olan veri hazırlama hizmeti (ing. Subscription Manager Data Preparation – SM-DP) ve güvenli yönlendirme hizmetine (ing. ing. Subscription Manager Secure Routing – SM-SR) ait teknik detaylar, uluslararası standartlar ve yerel mevzuat ışığında ele alınmıştır. Kurul kararları çerçevesinde yerelde şekillenecek olan e-SIM ekosistemine dair değerlendirmelere sonuç bölümünde yer verilmiştir., The e-Sim requirements for the machine-to-machine (M2M) ecosystem are defined by GSMA (GSMA, 2018). After the initial e-SIM standard was published by GSMA in 2016, the local legislation about e-SIM technologies will be subject to in Turkey was published by the Information Technology and Communication Committee on 12.02.2019. e-SIM ecosystems defined by GSMA; it is divided into two for consumers and for machine-to-machine networks. In this study, the e-SIM ecosystem for machine-to-machine networks is discussed and the e-SIM ecosystem for consumers is excluded from the scope. Key components of the e-SIM ecosystem for machine-to-machine networks are mobile network operators, data preparation service, secure routing service, e-SIM compatible devices, certification authority and device manufacturers. In this study, the technical details of SM-DP and SM-SR, which are the main components of the e-Sim ecosystem for the M2M, have been handled within the framework of international standards and local legislation. Evaluations for the Turkish e-SIM ecosystem, which will be shaped in line with the decisions of the ITC Committee, are discussed.

Published
2020

25. RELATIONSHIP BETWEEN CAROTID ARTERY DOPPLER FLOW VELOCITY AND EXTENT OF CORONARY ARTERY DISEASE

Author

Gündüz, Yasemin, Akdemir, Ramazan, Gündüz, Hüseyin, Perihan Varim, Lacin Tatli Ayhan, Çakar, Mehmet Akif, Vatan, Mehmet Bülent, Kılıç, Harun, Gunduz, Y, Akdemir, R, Gunduz, H, Varim, P, Ayhan, LT, Cakar, MA, Vatan, MB, Kilic, H, Sakarya Üniversitesi/Tıp Fakültesi/Dahili Tıp Bilimleri Bölümü, Gündüz, Yasemin, Akdemir, Ramazan, Gündüz, Hüseyin, Çakar, Mehmet Akif, Vatan, Mehmet Bülent, and Kılıç, Harun

Subjects
cardiovascular system, Cardiovascular System & Cardiology, cardiovascular diseases
Abstract

Conclusion: To Patients with carotid artery disease have a high incidence of concomitant coronary artery disease, which is not different between the patients treated conservatively and stenting. In addition, the extension of coronary artery disease (not the presence) were associated with these two Doppler parameters.

Published
2019

26. Budget impact of incorporating non-invasive prenatal testing in prenatal screening for Down syndrome in Turkey

Author

Ökem, Zeynep Güldem, Örgül, Gökçen, Çakar, Mehmet, Beksaç, Mehmet Sinan, Tarı Kasnakoğlu, Berna, Ökem, Zeynep Güldem, Örgül, Gökçen, Çakar, Mehmet, Beksaç, Mehmet Sinan, and Tarı Kasnakoğlu, Berna

Abstract

Objectives: To provide information to the government about the budget impact of implementing non-invasive prenatal testing (NIPT) into prenatal screening strategies to detect Down syndrome (DS) in singleton pregnancies in Turkey; the likely costs or savings associated with NIPT in comparison to the current practice were calculated. Methods: A decision-analytic model was developed to calculate the cost estimates for 1,309,771 women who gave birth in 2016; 84.8% of whom were 35-years-of-age. The superior combined test (CT) among current strategies is compared with contingent NIPT for women 35-years-of-age; and usual practice of amniocentesis (AC) for women ? 35 years-of-age was replaced with universal NIPT. Results: When the market price of NIPT (1,077 PPPUS$) is used, contingent NIPT offered to high-risk women 35-years-of-age adds 34,907,225 PPPUS$; and for women-35 ? years-of-age the universal NIPT leads to 142,785,818 PPPUS$ more cost to the government compared to current strategies. The additional costs with NIPT are partially compensated by the cost-savings due to reduction of the number of invasive tests and procedure related losses (17,826,476 PPPUS$ for women 35-years-of-age and 37,070 PPPUS$ for women ? 35-years-of-age). Results are sensitive to the NIPT costs; with a lower cost of NIPT, a total saving would be 33,116,046 PPPUS$ with new strategies. Conclusions: NIPT might be the choice of prenatal screening strategies if its price is lowered to economically acceptable levels. Until that time, currently accepted protocols seem to be more realistic. On the other hand, decision makers should also consider possible savings and the women's quality of life that can be improved with the new technology.

Published
2020

27. Concerns of Pregnant Women in Prenatal Screening/Diagnosis Practice and Termination of Pregnancy

Author

Fadıloğlu, Erdem, Tanacan, Atakan, Çakar, Mehmet, Ökem, Zeynep Güldem, Tarı Kasnakoğlu, Berna, Beksaç, Mehmet Sinan, Örgül, Gökçen, Fadıloğlu, Erdem, Tanacan, Atakan, Çakar, Mehmet, Ökem, Zeynep Güldem, Tarı Kasnakoğlu, Berna, Beksaç, Mehmet Sinan, and Örgül, Gökçen

Abstract

Objective To investigate the reasons for decision-making and concerns of patients in the field of prenatal screening, invasive prenatal diagnostic testing (IPDT), and termination of pregnancy (TOP). Study Design This questionnaire-based study consisted of 107 pregnant women who were referred for prenatal screening to the Hacettepe University Hospital. The questionnaire given to patients was prepared from scratch since there is no standard set of questions measuring patients' feelings and concerns regarding prenatal screening/diagnosis, IPDT, and TOP. Results Our questionnaire results showed that it is possible to classify decision-making factors into 6 groups: psychological, social, fear, religious/faith, support, and trust. The majority of patients were undecided (48.6%) about IPDT if prenatal screening test results were risky. Only 23.4% of patients were willing to accept IPDT. On the other hand, 55.1% of patients were not willing to undergo TOP if the fetal karyotyping results were abnormal. Religious factors seem to be important in refusing IPDT and TOP. Conclusion Physicians should re-evaluate their practice in the field of prenatal screening and diagnosis in light of the high refusal rates of IPDT and TOP. Understanding factors influencing women's decision-making processes provides insight for service providers to help women at high risk of having foetal anomalies to make better-informed choices.

Published
2020

28. Budget impact of incorporating non-invasive prenatal testing in prenatal screening for Down syndrome in Turkey

Author

Tarı Kasnakoğlu, Berna, Beksaç, Mehmet Sinan, Çakar, Mehmet, Ökem, Zeynep Güldem, Örgül, Gökçen, Tarı Kasnakoğlu, Berna, Beksaç, Mehmet Sinan, Çakar, Mehmet, Ökem, Zeynep Güldem, and Örgül, Gökçen

Abstract

Objectives: To provide information to the government about the budget impact of implementing non-invasive prenatal testing (NIPT) into prenatal screening strategies to detect Down syndrome (DS) in singleton pregnancies in Turkey; the likely costs or savings associated with NIPT in comparison to the current practice were calculated. Methods: A decision-analytic model was developed to calculate the cost estimates for 1,309,771 women who gave birth in 2016; 84.8% of whom were 35-years-of-age. The superior combined test (CT) among current strategies is compared with contingent NIPT for women 35-years-of-age; and usual practice of amniocentesis (AC) for women ? 35 years-of-age was replaced with universal NIPT. Results: When the market price of NIPT (1,077 PPPUS$) is used, contingent NIPT offered to high-risk women 35-years-of-age adds 34,907,225 PPPUS$; and for women-35 ? years-of-age the universal NIPT leads to 142,785,818 PPPUS$ more cost to the government compared to current strategies. The additional costs with NIPT are partially compensated by the cost-savings due to reduction of the number of invasive tests and procedure related losses (17,826,476 PPPUS$ for women 35-years-of-age and 37,070 PPPUS$ for women ? 35-years-of-age). Results are sensitive to the NIPT costs; with a lower cost of NIPT, a total saving would be 33,116,046 PPPUS$ with new strategies. Conclusions: NIPT might be the choice of prenatal screening strategies if its price is lowered to economically acceptable levels. Until that time, currently accepted protocols seem to be more realistic. On the other hand, decision makers should also consider possible savings and the women's quality of life that can be improved with the new technology.

Published
2020

34. Anjiyografi Hasta Plazmalarında, Paraoxonase 1, Arylesterase ve Total Thiol İncelemesi.

Author

YAZAR, Hayrullah, GÜNAY, Güler Kuşçu, İNCİ, Mustafa Baran, KALELİ, Süleyman, and ÇAKAR, Mehmet Akif

Abstract

Copyright of Online Turkish Journal of Health Sciences (OTJHS) / Online Türk Sağlık Bilimleri Dergisi is the property of Oguz KARABAY and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Published
2022
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37. Percutaneous Coronary Intervention for Chronic Total Occlusion versus Percutaneous Coronary Intervention for Non-Complex Coronary Lesions: Is There a Different Impact on Thyroid Function?

Author

Üreyen, Çağın Mustafa, Coşansu, Kahraman, Vural, Mustafa Gökhan, Şahin, Sait Emir, Çakar, Mehmet Akif, Kılıç, Harun, Ağaç, Mustafa Tarık, Gündüz, Hüseyin, Akdemir, Ramazan, Tatlı, Ersan, Üreyen, Çağın Mustafa, Vural, Mustafa Gökhan, Şahin, Sait Emir, Çakar, Mehmet Akif, and Ağaç, Mustafa Tarık

Subjects
PERCUTANEOUS coronary intervention, CONTRAST media, ENDARTERECTOMY
Abstract

Objective: This study assessed whether high levels of iodide administered during percutaneous coronary intervention (PCI) for chronic total occlusion (CTO) differentially influenced thyroid function compared to PCI for non-complex coronary lesions.Subjects and Methods: A total of 615 patients were enrolled in the study; 205 underwent elective PCI for CTO lesions (Group I) and 410 underwent elective PCI for non-complex lesions including non-CTO, non-bifurcation, non-calcified, and non-tortuous lesions (Group II). Patients were monitored for development of incidental thyroid dysfunction between 1 and 6 months after PCI.Results: The patients in Group I were administered a median of 255 mL of contrast medium during PCI for CTO; a median of 80 mL was administered to the patients in Group II during non-complex PCI (p =0.001). Ten (5.4%) of the 186 euthyroid patients in Group I and 19 (5%) of the 379 eu-thyroid patients in Group II developed subclinical hyper-thyroidism (p = 0.854). However, 7 (50%) of the 14 subclinical hyperthyroid patients in Group I and only 3 (12%) of the 25 subclinical hyperthyroid patients in Group II developed overt hyperthyroidism (p = 0.019).Conclusion: In euthyroid patients, PCI for coronary CTO lesions did not increase the risk for subclinical hyperthyroidism when compared to PCI for non-complex coronary lesions. However, in patients with subclinical hyperthyroidism at baseline, PCI for coronary CTO lesions significantly increased the development of overt hyperthyroidism when compared to PCI for non-complex coronary lesions. [ABSTRACT FROM AUTHOR]

Published
2020
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38. Stabil Angina Pektoris Hastalarında Tiyol/Disülfid Homeostazı Analizi

Author

YAZAR, Hayrullah, YILDIZ, Esra, İNCİ, Mustafa Baran, ÇAKAR, Mehmet Akif, ÖZBEK, Betül, BAL, Ceylan, and EREL, Özcan

Subjects
Native thiol,total thiol,disulphide,thiol/disulphide,stable angina pectoris, Health Care Sciences and Services, Sağlık Bilimleri ve Hizmetleri, Serbest tiyol,total tiyol,tiyol/disülfid,disülfid,stabil angina
Abstract

Objective: To investigate thiol/disulfide homeostasis in patients with stable angina pectoris.Materials and Methods: The study population consisted of 85 stable angina pectoris patients and 31 healthy volunteers. To compare the thiol/disulfide values of the patients and controls, the newly developed analysis method was used by Erel and Neselioglu. Disulfide/total thiol, free thiol/total thiol and disulfide/free thiol values were calculated for both groups.Results: Disulfide, free thiol and total thiol values obtained in the study were; 18.00 µmol/L, 365.08 µmol/L, 401.10 µmol/L for the patient group and 9.67 µmol/L for the control group, 372.51 µmol/L, 391.85 µmol/L for the control group. It is the first time thiol/disulphide homeostasis in plasma was examined by new developed method in stable angina pectoris patients with this study. Disulfide, disulfide/free thiol and disulfide/total thiol values were significantly higher in the patient group compared to the control group. free thiol/total thiol levels were significantly lower in patients (p, Amaç: Stabil angina pektoris tanılı hastaların tiyol/disülfid homeostazını incelemektir.Materyal ve Metot: Çalışma populasyonu 85 stabil angina pektoris hastası ile, 31 sağlıklı gönüllüden oluşmaktadır. Hasta ve kontrollerin tiyol/disülfid değerlerini karşılaştırmak için Erel ve Neşelioğlu tarafından yeni geliştirilen analiz metodu kullanılmıştır. Her iki grup için disülfid /total tiyol, serbest tiyol/total tiyol ve disülfid/serbest tiyol değerleri hesaplanmıştır. Bulgular: Çalışmada elde edilen disülfid, serbest tiyol ve total tiyol değerleri sırasıyla; hasta grubu için 18.00 µmol/L, 365,08 µmol/L, 401,10 µmol/L ve kontrol grubu için 9,67 µmol/L, 372,51 µmol/L, 391,85 µmol/L şeklinde bulunmuştur. Bu çalışma ile, stabil angina pektoris hastalarının tiyol/disulfid plazma değerleri yeni geliştirilen metot ile ilk defa belirlenmiştir. Disülfid, disülfid/serbest tiyol ve disülfid/total tiyol değerleri kontrole göre hasta grubunda anlamlı şekilde yüksek çıkarken; serbest tiyol/total tiyol değeri hastalarda anlamlı şekilde düşük çıkmıştır (p

Published
2019

41. What have health care reforms achieved in Turkey? An appraisal of the 'Health Transformation Programme'

Author

Çakar, Mehmet, Ökem, Zeynep Güldem, Çakar, Mehmet, and Ökem, Zeynep Güldem

Abstract

Poor health status indicators, low quality care, inequity in the access to health services and inefficiency due to fragmented health financing and provision have long been problems in Turkey's health system. To address these problems a radical reform process known as the Health Transformation Programme (HTP) was initiated in 2003. The health sector reforms in Turkey are considered to have been among the most successful of middle-income countries undergoing reform. Numerous articles have been published that review these reforms in terms of, variously, financial sustainability, efficiency, equity and quality. Evidence suggests that Turkey has indeed made significant progress, yet these achievements are uneven among its regions, and their long-term financial sustainability is unresolved due to structural problems in employment. As yet, there is no comprehensive evidence-based analysis of how far the stated reform objectives have been achieved. This article reviews the empirical evidence regarding the outcomes of the HTP during 10 years of its implementation. Strengthening the strategic purchasing function of the Social Security Institution (SSI) should be a priority. Overall performance can be improved by linking resource allocation to provider performance. More emphasis on prevention rather than treatment, with an effective referral chain, can also bring better outcomes, greater efficiency gains and contribute to sustainability. (C) 2015 Elsevier Ireland Ltd. All rights reserved.

Published
2019

42. Investigation new positions for catalytic activity of Chaetomium thermophilum and Ceriporiopsis subvermispora formate dehydrogenases.

Author

Koçdemir, Kübra, Şen, Fatma, Wedajo, Yasin Adem, Bilgici, Muazzez Çağla, Bayram, Mustafa, Selçuk, İlke, Yılmazer, Berin, Çakar, Mehmet Mervan, Aslan, Elif Sibel, and Binay, Barış

Subjects
DEHYDROGENASES, CHAETOMIUM, CATALYTIC activity, THERMAL stability, COFACTORS (Biochemistry), THERMAL properties
Abstract

NAD+-dependent formate dehydrogenases (FDHs, E.C 1.2.1.2) catalyse the reversible reaction of CO2 to formate ion (HCOO−) and reduces NAD+ molecule to NADH. Previously described FDHs from Chaetomium thermophilum (CtFDH) and Ceriporiopsis subvermispora (CsFDH) are active against formate and HCO3–. In this study, we examined the functional effects of active site mutations in Ct and Cs NAD+-dependent FDHs. The residues Ile94, Asn120, Val310, His312 at CtFDH and Asn312, Val313, Val331 at CsFDH are located in the active site. The effects of amino acid changes on catalytic properties and thermal stability of CtFDH and CsFDH revealed some interesting results compared with structurally equivalent positions that have been studied in the literature. The strongest effect was observed in CsFDH Val313Pro against HCO3–. The KM value of the CsFDH Val313 enzyme for HCO3– substrate dramatically decreased, and enzyme activity increased. In CtFDH mutants, all enzymes except Val310Asn showed an increased kcat value when KM values increase. Analyses of results of mutant CtFDHs and CsFDHs give some promising results for CO2 reduction as compared to the literature. Structural analyses of the substrate-binding site were done by homology modelling. [ABSTRACT FROM AUTHOR]

Published
2021
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43. Letter to the Editor

Author

Kahraman Cosansu, Vural, Mustafa Gökhan, Çakar, Mehmet Akif, Cosansu, K, Vural, MG, Cakar, MA, Sakarya Üniversitesi/Tıp Fakültesi/Temel Tıp Bilimleri Bölümü, Vural, Mustafa Gökhan, and Çakar, Mehmet Akif

Subjects
Cardiovascular System & Cardiology
Published
2017

45. Molecular characterization of NAD+-dependent formate dehydrogenase from Clostridium ljungdahlii

Author

Çakar, Mehmet Mervan, Binay, Barış, and Kimya Anabilim Dalı

Subjects
Biyokimya, Biyoteknoloji, Biochemistry, Biology, Biyoloji, Biotechnology
Abstract

NAD+-bağımlı format dehidrogenazlar, formatın CO2'ye dönüşümünü katalizleyen NAD(P)H'ye bağımlı oksidoredüktazlardır. Bu nedenle, kemoenzimatik işlemlerde kofaktör geri dönüşümü için yaygın şekilde kullanılırlar. Atmosferik karbondioksit seviyelerinin gittikçe artmasının yarattığı kaygı nedeniyle bu seviyenin azaltılması için yöntemlerin geliştirilmesine yönelik araştırmaların önemi yüksektir. Son zamanlarda ortaya çıkmış olan olasılıklardan biri, CO2'nin biyolojik açıdan faydalı karbon kaynaklarına enzimatik olarak dönüştürülmesidir. Bununla birlikte, yakın zamanda FDH enziminin ters yönde CO2'nin formata indirgenmesi için yüksek aktiviteye sahip olduğu keşfedilmiştir. Bu nedenle, bu çalışmada, aneorobik Clostridium ljungdahlii organizmasından fdh geni, E. coli'de ifade edilmek için klonlanmıştır. Proteinin yüksek miktarlarda ifadesini sağlayabilmek adına optimizasyon çalışmaları yapılmıştır ve optimum koşullar belirlenmiştir. Saf enzim, TAGzyme saflaştırma sistemi kullanılarak elde edimiştir. Metal bağımlı FDH'ler aktif bölgelerinde metal kümelerine sahip olabildikleri için, metallerin, ClFDH aktivitesi üzerindeki etkisi araştırılmıştır. Optimum pH aralığının belirlenmesinin ardından, ClFDH'nin termostabilitesini saptamak amacıyla sıcaklığın ClDH aktivitesi üzerine etkisi araştırılmıştır. Saflaştırılmış enzimin farklı sıcaklıklarda depolanmasının ardından aktivite ölçümleri yapılarak en iyi saklama koşulu ve kinetik analizlerle enzimin substratlarına karşı ilgisi belirlenmiştir.. Ayrıca, homoloji modellemesi çalışması ile enzimin yapısal analizi de sunulmuştur. ClFDH'nin biyokimyasal ve kinetik karakterizasyonu, enzimin ters yöndeki reaksiyonda, CO2'nin formata çevriminde de etkinliğe sahip olduğu göstermiştir. Biyoinformatik çalışmalar, ClFDH'nin CO2 indirgenmesinde iyi bir şablon olarak kullanılabileceğini göstermiştir. NAD+-dependent formate dehydrogenases (FDHs) are oxidoreductases catalysing the conversion of formate into CO2. Therefore they have been extensively used for cofactor recycling in different chemoenzymatic processes. With the growing concern of rising atmospheric CO2 levels, the importance of investigating all methods for its reduction is at an all-time high. One such possibility that has recently emerged is in the enzymatic conversion of CO2 into a biologically useful carbon source. It has been recently discovered that the FDHs enzymes also have high activity in the reverse direction, the reduction of aqueous CO2 to formate. Therefore, the fdh gene from aneorobic Clostridium ljungdahlii (Cl) was cloned for the expression in E. coli. Experimental studies were done to determine the optimum conditions for overexpression. Pure enzyme was obtained by using the TAGzyme purification system and effect of metals on the activity of ClFDH was investigated according to the metal centers presence in the active site of the enzyme. Effect of pH on the activity of ClFDH was studied to determine the optimum pH range. The effect of temperature on the activity was detected to determine the thermostability of the enzyme. Purified enzyme was stored at different temperatures in order to determine the best storage condition. Kinetic analysis of ClFDH activity were done to detect enzyme's affinity. Structural analysis of the enzyme via homology modeling is also presented. Biochemical and kinetic characterization of FDH from Clostridium ljungdahlii (ClFDH) has been shown to possess activity in the reverse reaction: the conversion of CO2 into formate. The obtained results show that ClFDH is a good template to engineer the enzyme to increase the activity for CO2 reduction. 50

Published
2018

46. Percutaneous Coronary Intervention for Chronic Total Occlusion versus Percutaneous Coronary Intervention for Non-Complex Coronary Lesions: Is There a Different Impact on Thyroid Function?

Author

Üreyen, Çağın Mustafa, primary, Coşansu, Kahraman, additional, Vural, Mustafa Gökhan, additional, Şahin, Sait Emir, additional, Çakar, Mehmet Akif, additional, Kılıç, Harun, additional, Ağaç, Mustafa Tarık, additional, Gündüz, Hüseyin, additional, Akdemir, Ramazan, additional, and Tatlı, Ersan, additional

Published
2019
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49. TÜRKİYE'DE MAKİNELER ARASI AĞLARA YÖNELİK UZAKTAN PROGRAMLANABİLİR GÖMÜLÜ SIM EKOSİSTEMİ.

Author

Çakar, Mehmet Akif

Subjects
INFORMATION & communication technologies, STANDARDS, ECOSYSTEMS, VEHICLE routing problem
Abstract

Copyright of SDU Journal of Engineering Sciences & Design / Mühendislik Bilimleri ve Tasarım Dergisi is the property of Journal of Engineering Sciences & Design and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Published
2020
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50. Engineered formate dehydrogenase from Chaetomium thermophilum, a promising enzymatic solution for biotechnical CO2 fixation.

Author

Çakar, Mehmet M., Ruupunen, Jouni, Mangas-Sanchez, Juan, Birmingham, William R., Yildirim, Deniz, Turunen, Ossi, Turner, Nicholas J., Valjakka, Jarkko, and Binay, Barış

Subjects
CHAETOMIUM, ALCOHOL dehydrogenase, STREPTOMYCES coelicolor, FORMIC acid, BIOCATALYSIS, DEHYDROGENASES, COFACTORS (Biochemistry)
Abstract

Objectives: Formate dehydrogenases (FDHs) are NAD(P)H-dependent enzymes that catalyse the reversible oxidation of formate to CO2. The main goal was to use directed evolution to obtain variants of the FDH from Chaetomium thermophilum (CtFDH) with enhanced reduction activity in the conversion of CO2 into formic acid. Results: Four libraries were constructed targeting five residues in the active site. We identified two variants (G93H/I94Y and R259C) with enhanced reduction activity which were characterised in the presence of both aqueous CO2(g) and HCO3−. The A1 variant (G93H/I94Y) showed a 5.4-fold increase in catalytic efficiency (kcat/KM) compared to that of the wild-type for HCO3− reduction. The improved biocatalysts were also applied as a coupled cofactor recycling system in the enantioselective oxidation of 4-phenyl-2-propanol catalysed by the alcohol dehydrogenase from Streptomyces coelicolor A3 (ScADH). Conversions in these reactions increased from 56 to 91% when the A1 variant was used instead of wild-type CtFDH. Conclusions: Two variants presenting up to five-fold increase in catalytic efficiency and kcat were obtained and characterised. They constitute a promising enzymatic alternative for CO2 utilization and will serve as scaffolds to be further developed in order to meet industrial requirements. [ABSTRACT FROM AUTHOR]

Published
2020
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