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Investigation of the inhibition effect of some plant extracts on aldose reductase activity
No full textLisansüstü Eğitim Enstitüsü, Kimya Ana Bilim DalıDiabetik komplikasyonların gelişiminde ve önlenmesinde, önemli bir rolü olan poliyol yolağı enzimlerinden Aldoz redüktaz (AR) (Alditol: NADP+ 1- oksidoredüktaz, E.C. 1.1.1.21) koyun böbreğinden kısmi olarak saflaştrıldı, Etanol, metanol ve su çözgenleri kullanılarak hazırlanan Viscum Album L. (ökse otu)'nun meyve, yaprak ve gövde kısımlarından hazırlanan ekstraktların enzim aktivitesi üzerine etkileri incelendi. AR enziminin kısmi saflaştırması homojenatın hazırlanması, amonyum sülfat çöktürmesi ve diyaliz basamakları ile gerçekleştirildi. 0,486 EÜ/mg protein spesifik aktivitesine sahip olan AR enzimi %44,43 verimle, yaklaşık 1,09 kat saflaştırıldı. Viscum Album L. bitki ekstraktlarının aldoz redüktaz (AR) enzimi üzerine in vitro ve in siliko inhibisyon etkileri araştırıldı. In vitro inhibisyon etkileri spektrofotometrik yöntemle belirlendikten sonra, moleküler docking yöntemi ile bağlanma enerjisi ve bağlanma modları belirlendi. Viscum Album L. bitkisinin gövde kısmının methanol çözgeni kullanılarak hazırlanan ekstraktın AR enzimine karşı, 0.156 µM IC50 değeri ile en güçlü inhibisyon etki gösteren ekstarkt olduğu belirlenmiştir. Viscum Album L bitkisinin meyve kısımlarının etanol, methanol ve su çözgenleri kullanılarak hazırlanan ekstraktların IC50 değerleri sırasıyla 1.174 ?M, 0.860 ?M,1.560 ?M, bitkinin yaprak kısımlarının etanol, methanol ve su çözgenleri kullanılarak hazırlanan ekstraktların IC50 değerleri sırasıyla 1.090 ?M, 0.190 ?M, 9.260 ?M ve bitkinin gövde kısımlarının etanol, methanol ve su çözgenleri kullanılarak hazırlanan ekstraktların IC50 değerleri sırasıyla 0.700 ?M, 0.153 ?M, ve 0.906 ?M olarak belirlenmiştir. Bu çalışmanın sonuçları, Viscum Album L bitki ekstraktlarının etkili birer AR inhibitor olabileceğini göstermiştir. AR enzimine karşı in vitro inhibisyon etkisi gösteren ekstraktlarda yapılan moleküler docking sonuçları da edinilen verileri desteklemektedir.Aldose reductase (AR) (Alditol: NADP+ 1-oxidoreductase, E.C. 1.1.1.21), one of the polyol pathway enzymes that has an important role in the development and prevention of diabetic complications, was partially purified from sheep kidney. Viscum Album L. (The effects of extracts prepared from fruit, leaf and stem parts of mistletoe) on enzyme activity were investigated. Partial purification of AR enzyme was performed by preparation of homogenate, ammonium sulfate precipitation and dialysis steps. The AR enzyme, which has a protein specific activity of 0.486 EU/mg, was purified approximately 1.09-fold, with a yield of 44.43%. In vitro and in silico inhibition effects of Viscum Album L. plant extracts on aldose reductase (AR) enzyme were investigated. After the in vitro inhibition effects were determined by spectrophotometric method, the binding energy and binding modes were determined by molecular docking method. It was determined that the extract prepared by using the methanol solvent of the stem part of the Viscum Album L plant has the strongest inhibitory effect against the AR enzyme with an IC50 value of 0.156 µM. The IC50 values of the extracts prepared using ethanol, methanol and water solvents of the fruit parts of the Viscum Album L plant are 1.174 ?M, 0.860 ?M, 1.560 ?M, respectively, and the IC50 values of the extracts prepared using the ethanol, methanol and water solvents of the leaf parts of the plant are 1.090 ?M, 0.190 ?M, 9.260 ?M, respectively. and the IC50 values of the extracts prepared using ethanol, methanol and water solvents of the stem parts of the plant were determined as 0.700 ?M, 0.153 ?M, and 0.906 ?M, respectively. The results of this study showed that Viscum Album L plant extracts can be effective AR inhibitors. The results of molecular docking of the extracts showing an in vitro inhibition effect against the AR enzyme also support the data obtained
Türkiye Florası İçin Yeni Bir İstilacı Bitki Kaydı: Grindelia hirsutula Hook. & Arn.
No full textTürkiye’de son yıllarda birçok istilacı bitki kaydı verilmiştir. Bunların bazıları tıbbi ve ekonomik öneme sahip olduğundan bahçe veya tarla kaçkını olarak değerlendirilmektedir. Bahçe kaçkını olduğu düşünülen ve tıbbi kullanımı (üst solunum yolları enfeksiyonlarının tedavisi) olan Grindelia hirsutula stilacı bir bitki olarak Kütahya ilimizde tespit edilmiştir. Bu istilacı bitki kaydı aynı zamanda ülkemiz florası için yeni bir cins kaydı (Grindelia) niteliğindedir. Bitkiye ait betimlemelerin yanı sıra fotoğraflar ve ayırt edici karakterler (papus kılçıkları, glandular tüyler ve yaprak özellikleri gibi) makalede sunulmuştur. Grindelia hirsutula’nın ülkemiz florasında yer alan Inula cinsinden farklılıkları belirlenmiştir. Bitkinin Kew Herbaryumu’nda bulunan isotip örneğine ait bilgilere ve dünya üzerindeki yayılışına yer verilmiştir
Determination of radiation shielding characteristics of some essential nickel-based alloys that can be used in nuclear energy applications
No full textLisansüstü Eğitim Enstitüsü, Fizik Ana Bilim Dalı, Fizik Bilim DalıBu tez çalışmasında, geleneksel radyasyon zırhlama malzemelerinin yetersizliğinden dolayı nükleer enerji uygulamalarına entegre edilebilmek için optimal koşulları sağlayan yeni malzemelerin keşfine odaklanılmıştır. Bu kapsamda, Evanohm, Alloy 825, Haynes 230, Monel K-500 ve Monel 400 olarak adlandırılan beş farklı Ni-tabanlı alaşımın radyasyon zırhlama performansları ve karakteristik özellikleri araştırılmıştır. Bu alaşımların radyasyon zırhlama performanslarını belirlemek için, ilk olarak, foton-madde etkileşim parametreleri (MAC, LAC, HVL, MFP, ACS, ECS, Zeff, Neff, ?eff ve RPE) 30-1333 keV enerji aralığında EDXRF tekniği kullanılarak deneysel olarak belirlenmiştir. Aynı zamanda, deneysel hataların belirlenmesi için bu parametreler Phy-X/PSD yazılımı kullanılarak teorik olarak da hesaplanmıştır. İkinci olarak, malzemelerin foton saçılma özellikleri hakkında bilgi veren Rinc/toplam, Zeq, EBF ve EABF parametreleri 0,015-15 MeV geniş enerji aralığında hesaplanmıştır. İncelenen alaşımların radyasyon zırhlama yetenekleri çelik-manyetit (SM) betonu ve Cupero-Nikel (CN) alaşımı ile karşılaştırılmıştır. Son olarak, elde edilen sonuçlara dayanılarak alaşımların fiziksel, kimyasal, mekanik, termal ve radyasyon zırhlama özellikleri birlikte değerlendirilerek nükleer enerji uygulamalarında kullanılabilecek en uygun alaşımın seçimi yapılmıştır. Araştırma sonucunda, incelenen malzemelerin radyasyon zırhlama performans sıralamaları Haynes 230>CN>Monel 400>Monel K-500>Evanohm>Alloy 825>SM olarak belirlenmiştir. Ayrıca, Haynes 230 alaşımın diğer alaşımlardan yaklaşık %40 daha fazla zırhlama performansı gösterdiği saptanmıştır. Bu sonuca ek olarak, Haynes 230 alaşımının incelenen diğer Ni-tabanlı alaşımlara göre daha iyi kırılma direncine (%CN>Monel 400>Monel K-500>Evanohm>Alloy 825>SM. Moreover, it was determined that Haynes 230 alloy showed approximately 40% more shielding performance than other alloys. In addition to this result, it was determined that Haynes 230 alloy has better elongation at break (%<50), better tensile strength (860 MPa), better elastic modulus (211 GPa), lower thermal conductivity (8.9 W.m-1.K-1 at 23 0C), lower specific heat (397 J.K-1.kg-1 at 23 0C), greater density (8.97 g/cm3), low thermal expansion coefficient (13x10-6 K-1 at 20-150 0C) and high melting point (~1350 0C) than other investigated Ni-based alloys. Thus, it was observed that the Haynes 230 alloy meets the optimal properties that can be used in nuclear applications with these superior characteristics. Consequently, it has been concluded that this alloy can be used as a building material in reactor design in nuclear applications and as a shielding material in nuclear power plants and other ionizing radiation applications
Ultrasonic extraction conditions using response surface methodology: total phenolic content of bee pollen
No full textBee pollen plays a significant role in bee nutrition, bee population sustainability, pollination processes, and its health and nutritional benefits for humans. It contains protein, vitamins, minerals, and antioxidants, offering valuable nutritional properties. The total phenolic content (TPC) is an important parameter in determining the nutritional and health value of pollen. The presence of high levels of phenolic compounds in pollen enhances their health benefits and can provide protective effects against diseases by combating oxidative stress. In the study, ultrasonic extraction conditions for pollen were optimized using the Response Surface Method to maximize TPC. The experimental study was designed according to Box-Behnken design: 30–70% ethanol ratio, 5–15 min of extraction time, and 10–20% ultrasonic amplitude modulation (AM). The TPC of the obtained extracts were determined using the Folin-Ciocalteu procedure. The optimal extraction conditions were predicted as 60.012% ethanol ratio, 11.054 min, and 19.160% AM for reaching 9.572 mg/GAE g extract
The Effect of Different Drying Methods on Bioactive and Nutrition Contents of Bee Bread and Mathematical Modeling of Drying Characteristics
No full textIn this study, the aim was to determine the effect of different drying methods (with microwave and hot air) on the color, nutrient and bioactive contents of fresh bee bread. Drying characteristics were also investigated. Microwave and hot air drying were applied at different microwave powers and temperatures, respectively. Lower moisture ratios and highest effective diffusion coefficients were obtained with microwave drying in a shorter time. The Midilli model was found to be the most suitable thin-layer drying model for both methods. Regardless of the drying conditions, moisture, ash, protein, carbohydrate, and lipid proportions were observed to vary in the ranges of 4.9-8.2 %, 1.61-2.67 %, 17.47-32.54 %, 39.92-60.84 %, and 7.10-8.89 %, respectively. The lowest color difference was obtained for the sample dried at 210 W. As a result, it was determined that microwave drying is more suitable for preserving the nutritional and bioactive content of bee bread during drying
Analysis of telomere length in patients with COVID-19 and investigation into its relationship with clinical- demographic data
No full textPurpose: Novel coronavirus disease 2019 (COVID-19) is an infectious disease unknown before the 2019 outbreak in Wuhan. This study evaluated telomere length in COVID-19 (+) and (-) samples with clinical-demographic parameters.Materials and Methods: DNA was isolated from COVID-19 (+) (n=70) and (-) (n=70) patients. Telomere length was determined by real-time-PCR (RT-PCR). The 2- increment increment Ct method was used to analyze the telomere length of the samples.Results: There were significant differences in creatinine, LDH, ferritin, WBC, NEU and CRP in COVID-19 (+) patients compared to COVID-19 (-) patients. The NEU/LYM (or N/L) ratio was found higher in the patients with COVID-19 (+), than in COVID-19 (-). On the other hand, our COVID-19 (+) patients (mean +/- std:0.93 +/- 0.58) had significantly shorter telomere lengths than the COVID-19 (-) (mean +/- std:1.26 +/- 0.76). Moreover, COVID-19 (+) male patients (mean +/- std:1.06 +/- 0.50) had longer telomere length than female patients (mean +/- std:0.76 +/- 0.54). Telomere length was significantly shorter in patients with COVID-19 (+) with high blood urea nitrogen (BUN), high creatinine, high hematocrit, high NEU levels, normal platelets (PLT), and low WBC levels.Conclusion: Our findings suggest that telomere length and blood parameter levels influence the severity of COVID-19. Blood parameters differed in patients with COVID-19 (+) and COVID-19 (-). As a result, increasing the number of similar studies in the future can demonstrate the significance of our findings
A Cross-Cultural Analysis of a Turkish EFL Textbook: Hu and McKay's Analytic Framework
No full textDue to rapid globalization, culture is an essential element of foreign language pedagogy. Cross-cultural communication and foreign language learning have become increasingly important since it provides the common basis for intercultural contact. Textbooks are crucial pedagogical resources in the EFL context since they are the primary sources of building intercultural understanding. The main purpose of this study was to explore how a local Turkish EFL textbook presented interlingual and intercultural diversity in Turkish EFL classrooms. Hu and McKay's (2014) analytic framework was adopted to investigate the linguistic and cultural contents of the textbook. The findings revealed that the textbook needed more group work activities, which does not promote communication enough. In addition, the cultural content was dominated by the native culture (Turkish). In the textbook, mainstream contexts (i.e., family, school, holidays) along with local Turkish cultural elements formed the majority of the settings. In addition, places, names, and events were mainly from Turkiye, while these elements from other cultures, including Anglo-American, were limited. Finally, cross-cultural conversations were included; however, the topics chosen were about Turkiye and popular culture. These findings were discussed regarding cross-cultural communication, EIL and practical ELT pedagogy
Designing New Model-Based Adaptive Sliding Mode Controllers for Trajectory Tracking Control of an Unmanned Ground Vehicle
No full textThis paper proposes three new dynamic model-based adaptive sliding mode controllers (ASMC) for trajectory tracking control of unmanned ground vehicles (UGV). The controllers combine kinematic and dynamic control to achieve asymptotic stability and finite-time convergence and their stability is verified using the Lyapunov stability theory. The controllers are designed to address the challenges posed by uncertainties in vehicle dynamic parameters and outperform the sliding mode control (SMC) method in trajectory tracking control. The simulation results of the proposed controllers are also discussed in terms of performance metrics. The simulation results show that the controller proposed in rule 1 shows the better performance in terms of trajectory tracking, and then the controllers proposed in rules 2 and 3 have good performances, respectively. In addition, when the simulation results are compared, it is seen that the performance of all three proposed controllers is better than the SMC
Physicochemical Characterization of Dextran HE29 Produced by the Leuconostoc citreum HE29 Isolated from Traditional Fermented Pickle
No full textIn this study, lactic acid bacteria (LAB) strains were isolated from traditional fermented pickles, and among the identified strains, Leuconostoc citreum HE29 with a strong slimy colony profile was further selected to determine the physicochemical and techno-functional properties of its exopolysaccharide (EPS). Glucose was the only sugar monomer in the core unit of EPS HE29 detected by HPLC analysis, and glucan HE29 revealed 7.3 kDa of molecular weight. Structural characterization of glucan HE29 by H-1 and C-13 NMR spectroscopy analysis demonstrated that EPS HE29 was a dextran-type EPS containing 5.3% levels of (1 -> 3)-linked alpha-D-glucose units. This structural configuration was also supported by FT-IR analysis, which also demonstrated the functional groups within the dextran HE29 structure. In terms of thermal properties detected by TGA and DSC analysis, dextran HE29 demonstrated a degradation temperature of around 280 degrees C, showing its strong thermal features. A semi-crystalline nature was observed for dextran HE29 detected by XRD analysis. Finally, AFM and SEM analysis revealed tangled network-like properties and web-like branched structures for dextran HE29, respectively. These findings suggest the importance of plant-based fermented products as LAB sources in obtaining novel EPS structures with potential techno-functional roles
The Blockchain Usage and Current Trends in the Tourism Sector: A Conceptual Research
No full textToday, with changes and developments in technology, there are changes in concepts, uses, and even in daily life, and it is seen that this situation permeates all areas of life. In this context, many new types of technology have emerged. Blockchain is one of these technologies and is one of the applications in the tourism sector in human life. Therefore, it is necessary to examine this phenomenon by focusing on the studies carried out to perceive the possible results of both software and hardware applications realized with technologies developed on blockchain, and to understand the opportunities that may arise in the tourism sector. Accordingly, in this study, particularly studies on the areas where tourism and blockchain intersect are examined and a conceptual analysis is conducted on these topics by determining the topics of blockchain use in Europe and the USA from the perspective of basic accommodation services, tourist data, medical tourism, and global application areas. Based on this academic framework, an application suggestion for Türkiye is also provided