Chemistry / Kimya
Permanent URI for this collectionhttps://hdl.handle.net/11147/4072
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Review Citation - WoS: 116Citation - Scopus: 125Salivary Biomarkers: Novel Noninvasive Tools To Diagnose Chronic Inflammation(Springer, 2023) Dongiovanni, Paola; Meroni, Marica; Casati, Sara; Goldoni, Riccardo; Thomaz, Douglas Vieira; Kehr, Nermin Seda; Galimberti, DanielaSeveral chronic disorders including type 2 diabetes (T2D), obesity, heart disease and cancer are preceded by a state of chronic low-grade inflammation. Biomarkers for the early assessment of chronic disorders encompass acute phase proteins (APP), cytokines and chemokines, pro-inflammatory enzymes, lipids and oxidative stress mediators. These substances enter saliva through the blood flow and, in some cases, there is a close relation between their salivary and serum concentration. Saliva can be easily collected and stored with non-invasive and cost-saving procedures, and it is emerging the concept to use it for the detection of inflammatory biomarkers. To this purpose, the present review aims to discuss the advantages and challenges of using standard and cutting-edge techniques to discover salivary biomarkers which may be used in diagnosis/therapy of several chronic diseases with inflammatory consequences with the pursuit to possibly replace conventional paths with detectable soluble mediators in saliva. Specifically, the review describes the procedures used for saliva collection, the standard approaches for the measurement of salivary biomarkers and the novel methodological strategies such as biosensors to improve the quality of care for chronically affected patients.Article Citation - WoS: 7Citation - Scopus: 6Visceral Leishmaniasis Caused by Leishmania Tropica(Springer, 2023) Özbilgin, Ahmet; Tunalı, Varol; Çavuş, İbrahim; Vardarlı Tetik, Aslı; Dinç, Melike; Yalçın, Talat; Gündüz, Cumhur; Beyaz, Merve; Köse, ŞükranPurposeIn Turkey, the main causative agent of visceral leishmaniasis (VL) is Leishmania. infantum and the main causative agent of cutaneous leishmaniasis (CL) is Leishmania tropica. In this study, we aimed to discuss the possible mechanisms, clinical aspects, and threat of visceralizing L. tropica.MethodsThis study includes seven cases of VL caused by L. tropica.Five patients were male (71%) and four were adults (57%).ResultsAll the VL patients complained of fever and splenomegaly. Fatigue, pancytopenia, and hepatomegaly were present in six patients each (86%), while weight loss and gastrointestinal system (GIS) symptoms were present in 5 patients (71%).ConclusionsIn this study, we have evaluated seven cases of visceralized L. tropica (VLT) in the context of the changing leishmaniasis epidemiology in Turkey. We have evaluated the possible mechanisms of visceralization; inter- and intraspecies genetic exchange with all the old world leishmaniasis agents present in the region, stress induced by inappropriate use of drugs, and possible ongoing adaptation mechanisms of Leishmania spp. The threat posed by VLT is significant as L. tropica is the most widespread and most common cause of leishmaniasis in Turkey. We do not know the vectorial capacity of the sand flies for the transmission of VLT strains or if these strains are in circulation in Turkey. Future studies should be carried out to investigate these issues as the transition of L. tropica from a mild disease-causing agent to a mortal one poses a significant public health concern for Turkey and Europe.Article Citation - WoS: 2Citation - Scopus: 2Tuning the Solid Phase Fluorescence Emission From Long Wavelength Visible To Near-Infrared in Oxazol-5 Derivatives: Structure–property Relationship, Theoretical and Experimental Studies(Springer, 2023) Nazlı, İbrahim Hanif; Yakalı, Gül; Topkaya, Derya; İzmirli, Merve; Uzun, Sema Demirci; Alp, SerapMost of the fluorescent molecules among organic π-conjugated materials show blue or green emission in the solid phase but few of them emit red-shifted visible and near-infrared light in the material science. To create molecules emitting for this feature, two π-conjugated oxazol-5-one derivatives containing donor (OCH3) and acceptor groups (NO2) were synthesized. Their optical and charge-transport properties were investigated through experimental and theoretical methods including the single crystal X-ray crystallography, Hirshfeld Surface Analysis, photophysical studies and Density Functional Theory (DFT), respectively. In addition, FT-IR, 1H-NMR, 13C-NMR spectroscopy, cyclic voltammetry (CV) measurements were performed. According to our results, both molecules may provide the significant pathway of development of long wavelength visible and red emissive features in solid phase with the aggregation induced enhanced emission (AIEE) properties particularly in the fields of OLEDs, optical communication, defence and bioimaging.Article Citation - WoS: 11Citation - Scopus: 16Purification and Biochemical Characterization of a Novel Thermostable Serine Protease From Geobacillus Sp. Gs53(Springer, 2021) Şanlı Mohamed, Gülşah; Güracar Baykara, Seden; Sürmeli, YusufProteases account for approximately 60% of the enzyme market in the world, and they are used in various industrial applications including the detergent industry. In this study, production and characterization of a novel serine protease of thermophilic Geobacillus sp. GS53 from Balcova geothermal region, Izmir, Turkey, were performed. The thermostable protease was purified through ammonium sulfate precipitation and anion-exchange chromatography. The results showed that the protease had 137.8 U mg(-1) of specific activity and optimally worked at 55 C-o and pH 8. It was also active in a broad pH (4-10) and temperature (25-75 degrees C) ranges. The protease was highly stable at 85 degrees C and demonstrated relative stability at pH 4, 7, and 10. Also, the enzyme had high stability against organic solvents and surfactants; enzyme relative activity did not decrease below 81% upon preincubation for 10 min. Ca2+, Cu2+, and Zn2+ ions slightly induced protease activity. The protease was highly specific to casein, skim milk, Hammerstein casein, and BSA substrates. These results revealed that the protease might have a potential effect in a variety of industrial fields, especially the detergent industry, because of its high thermostability and stability to surfactants.Article Citation - WoS: 6Citation - Scopus: 5Charmm Force Field Generation for a Cationic Thiophene Oligomer With Fftk(Springer, 2021) Kıbrıs, Erman; Nalıncı Barbak, Nehir; Elmacı Irmak, NuranIn the present work, CHARMM force field parameters are generated for a cationic oligomer of N, N, N-trimethyl-3-(4-methylthiophen-3-yl) oxy) propan-1-aminium) which has the potential for sensing biological molecules such as nucleic acids, nucleobases. We have used ffTK (force field tool kit) to obtain potential parameters. MD simulations are performed for 20-mer and its complexes with AMP and ATP. The simulation results are analyzed to see the number of phosphates in adenosine nucleotides effects on the structure of the backbone of oligomer. The UV-VIS calculations for the conformers which possess the most probable radius of gyration are carried out and compared to the experimental ones to validate the generated force field. Recent studies have shown that, biologically important anions (ATP, AMP, vb.) change the spectroscopic properties of cationic polythiophenes (CPT) in the solutions. This work aims to generate CHARMM compatible force field parameters for a CPT to explain experimental studies. The type of interactions will be investigated deeply to lead new biosensor studies by examining the formation and the structure of complexes that consist of a oligothiophene and biological molecules, ATP, AMP by molecular dynamic simulations.Article Citation - WoS: 9Citation - Scopus: 9Tuning Photoinduced Intramolecular Electron Transfer by Electron Accepting and Donating Substituents in Oxazolones(Springer, 2013) Öztürk, Gülsiye; Karabıyık, Hasan; Aygün, Muhittin; Alp, Serap; Özçelik, SerdarThe solvatochromic and spectral properties of oxazolone derivatives in various solvents were reported. Fluorescence spectra clearly showed positive and negative solvatochromism depending on substituents. The solvatochromic plots and quantum chemical computations at DFT-B3LYP/6-31+G(d,p) level were used to assess dipole moment changes between the ground and the first excited singlet-states. The electron accepting nitro substituent at the para-position increased the π-electron mobility, however, the 3,5-dinitro substituent decreased the π-electron mobility as a result of inverse accumulation of the electronic density as compared with that of its ground state. Experimental and computational studies proved that the photoinduced intramo- lecular electron transfer (PIET) is responsible for the observed solvatochromic effects. We demonstrate that PIET can be finely tailored by the position of the electron accepting and donating substituents in the phenyl ring of the oxazolone de- rivatives.We propose that the photoactive CPO derivatives are new molecular class of conjugated push-pull structures using azlactone moiety as the π-conjugated linker and may find applications in photovoltaic cells and light emitting diodes.