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Öğe Antimicrobial activity of phytic acid, citric acid, and EDTA with and without propolis against Enterococcus Faecalis and Candida Albicans(Mashhad University of Medical Sciences, 2022) Özata, Merve Yeniçeri; Acer, Ömer; Demirci, Özlem; Çolak, Mehmet; Tartuk, Gizem AkınIntroduction: This study aimed to investigate the antimicrobial efficacy of chelation agents on Enterococcus faecalis (E. faecalis) and Candida albicans (C. albicans) when used alone or in combination with propolis. Methods: One hundred fifty mandibular premolar teeth were selected. Each canal was prepared with Reciproc R25. The roots were then divided into two parts along their long axis (n=300). For E. faecalis and C. albicans, the samples were divided into 16 groups (14 experimental and 2 control) as follows: Group 1A-1B [17% Ethylenediaminetetraacetic acid (EDTA)], Group 2A-2B [10% Citric Acid (CA)], Group 3A-3B [1% phytic acid/inositol hexaphosphate (IP6)], Group 4A-4B (17% EDTA+8 mg/mL propolis), Group 5A-5B (10% CA+8 mg/mL propolis), Group 6A-6B (1% IP6+8mg/mL propolis), Group 7A-7B (8 mg/mL propolis), Control A-B (Dimethyl Sulfoxide). Each tooth was randomly irrigated with 2 mL of one of the group solutions or dispersions for 5 min, and the solutions were examined for the bactericidal effect. Results: For C. albicans, all groups showed less optical density (OD) than the control group (P<0.05). The propolis group and the IP6 group had higher OD values than the CA group (P<0.05). For E. faecalis, on the other hand, significantly lower OD values were observed in the propolis+ CA group, compared to the CA and propolis groups (P<0.05). There was no significant difference between microbial growth among IP6, EDTA, propolis+ CA, propolis+IP6, and propolis+ EDTA groups (P>0.05). Conclusion: CA and IP6 showed promising results in eliminating E. faecalis, one of the collective organisms responsible for failed root canals.Öğe Antioxidant responses in Phanerochaete chrysosporium exposed to Astrazone Red FBL textile dye(Wiley, 2013) Demirci, Özlem; Hamamcı, Dilek Asma; 0000-0001-9511-2010; 0000-0002-3866-3016Interest in environmental-pollutant-induced oxidative stress and knowledge of the interactions between reactive oxygen species and cellular systems have increased in toxicology and microbial ecology considerably in recent decades. These reactive oxidants are produced by a variety of environmental sources: ionizing radiations, ultraviolet light, redox cycling drugs, hyperoxia, ischemia and redox-active xenobiotics or during metabolism of environmental pollutants, such as heavy metals in mining industries, dyes in wastewater of textile industries, pesticides and polycyclic hydrocarbons, i.e. foreign materials. In this study, the effect of dye on the antioxidative defence system of Phanerochaete chrysosporium was investigated, and we showed the ability of Phanerochaete chrysosporium to antioxidative response and defence system exposed to Astrazone Red FBL. Catalase, glutathione reductase, glutathione s-transferase activities and level of glutathione decreased, depending on the period of growth in each exposure to low and high concentration group (20 and 50?ppm) compared with the control group. Copyright (c) 2012 John Wiley & Sons, Ltd.Öğe Aroclor 1254’e maruz kalan elastinin yapısında meydana gelen değişikliklerin incelenmesi(Dicle Üniversitesi Fen Bilimleri Enstitüsü, 2020) Demirci, Özlem; Uğurlu, Pelin; Bingölbalı, Nurcan Doğan; Acer, Ömer; Kılınç, ErsinElastin prolin, valin ve glisin aminoasitlerinin yoğun olarak yer aldığı hidrofobik bölge ve alanin aminoasitinin yer aldığı çapraz bağlanma bölgesinden oluşan ve omurgalı canlıların dokularına esneklik ve hareketlilik sağlayan bir protein çeşididir. Elastinde meydana gelecek hasarlar pek çok hastalığa neden olduğundan elastin proteini üzerine çok sayıda araştırma yapılmıştır. Fakat toksik bir maddeye maruz kalan elastinde oluşacak hasarla ilgili çalışmalar literatürde sınırlı sayıdadır. Bu amaçla önemli kalıcı organik kirleticilerden biri olan Aroclor 1254’e maruz kalan elastin proteininin yapısında meydana gelen değişiklikler histopatolojik olarak incelenmiş ve oluşan hasarın konsantrasyona bağlı olduğu tespit edilmiştir.Öğe Çeşitli pestisitlerin "Gammarus kischineffensis"in antioksidan enzim sistemi ve bazı biyobelirteçler üzerine etkisi(2016) Demirci, Özlem; Güven, KemalDünyada en fazla kullanılan tarımsal mücadele yöntemleri, kimyasal yöntemlerdir. Kimyasal mücadelenin temelinde pestisit denilen sentetik zirai maddeler vardır. Pestisitler tarımda kullanılan, ürün kaybına yol açan böcek, hayvan ve bitkilerin gelişimini önlemek, bu zararlı canlıları yok etmek, geri püskürtmek veya bu canlıların sayısını azaltmak için üretilmiş kimyasal maddeler ya da biyolojik ajanlardır (virüs, bakteri). Bilinçsiz pestisit kullanımı sonucunda insan, hava, su, toprak ve yabani hayat olumsuz etkilenmekte, hedef alınan canlılarda direnç oluşmakta, doğal hayatın ve yararlı canlıların öldürülmesiyle doğal denge bozulmakta ve bitkilerde fitotoksisite görülmektedir. Yüzey suları ve içerdikleri doğal kommünite, pek çok antropojenik toksik kimyasalla kontamine olmuştur. Sucul ekosistemlerin korunabilmesi için bu kimyasalların etkilerinin değerlendirilmesi gerekmektedir. Bu antropojenik kimyasallardan en ciddi problem yaratanlar pestisitlerdir. Çünkü pestisitler canlıları (hem hedef hem de hedef olmayan organizmaları) öldürmek için özel olarak tasarlanmış ve çoğunlukla kasıtlı olarak doğaya bırakılan kimyasallardır. Yoğun tarım, hava ve yüzey sularının kirlenmesine, su sistemlerinin ötrifikasyonuna, sera gazları emisyonlarına ve asit yağmurlarına neden olmaktadır. Uzun zamandır tarımsal alanlarda zararlılarla mücadele etmek, dolayısı ile verimi artırmak için kullanılan pestisitler insan sağlığını ve çevreyi ciddi anlamda tehdit etmektedir. Çalışmamızda kullandığımız Gammarus kischineffensis, Crustacea sınıfına ait bir türdür. Crustacea sınıfına ait türler genelde su sistemlerindeki kirliliği belirlerken biyoindikatör olarak kullanılmaktadır. Ayrıca Gammarus kischineffensis balıklar için besin kaynağıdır bu nedenle besin piramidinin temel basamaklarından birini oluşturmaktadır ve biyolojik birikimdeki yeri nedeniyle önem arz etmektedir. Bu araştırma kapsamında, endosulfan, indoxacarb, thiomethoxam ve atrazinin ve bu pestisitlerin kombine kullanımlarının, Gammarus kischineffensis?in antioxidan ve detoksifikasyon enzimleri üzerine etkilerinin incelenmesi ve bu organizmalarda bıraktığı kalıntı düzeyleri araştırılmıştır. Sonuç olarak, pestisitlerin tek ve kombine kullanımlarının Gammarus kischineffensis'in antioksidan ve detoksifikasyon enzimleri üzerinde etkili olduğu gözlenmişir. Endosulfan dışındaki tüm pestisitler için kalıntı tespit edilmiştir ve sonuçların enzim cevapları ile uyumlu olduğu belirlenmiştir. Anahtar Kelimeler: Gammarus kischineffensis, antioksidan enzimler, asetilkolinesteraz, pestisit kalıntısı.Öğe EDI3 knockdown in ER-HER2+ breast cancer cells reduces tumor burden and improves survival in two mouse models of experimental metastasis(BioMed Central Ltd., 2024) Glotzbach, Annika; Rohlf, Katharina; Gonscharow, Anastasia; Lüke, Simon; Demirci, Özlem; Overbeck, Nina; Tibbe, Brigitte BegherBackground: Despite progress understanding the mechanisms underlying tumor spread, metastasis remains a clinical challenge. We identified the choline-producing glycerophosphodiesterase, EDI3 and reported its association with metastasis-free survival in endometrial cancer. We also observed that silencing EDI3 slowed cell migration and other cancer-relevant phenotypes in vitro. Recent work demonstrated high EDI3 expression in ER-HER2+ breast cancer compared to the other molecular subtypes. Silencing EDI3 in ER-HER2+ cells significantly reduced cell survival in vitro and decreased tumor growth in vivo. However, a role for EDI3 in tumor metastasis in this breast cancer subtype was not explored. Therefore, in the present work we investigate whether silencing EDI3 in ER-HER2+ breast cancer cell lines alters phenotypes linked to metastasis in vitro, and metastasis formation in vivo using mouse models of experimental metastasis. Methods: To inducibly silence EDI3, luciferase-expressing HCC1954 cells were transduced with lentiviral particles containing shRNA oligos targeting EDI3 under the control of doxycycline. The effect on cell migration, adhesion, colony formation and anoikis was determined in vitro, and significant findings were confirmed in a second ER-HER2+ cell line, SUM190PT. Doxycycline-induced HCC1954-luc shEDI3 cells were injected into the tail vein or peritoneum of immunodeficient mice to generate lung and peritoneal metastases, respectively and monitored using non-invasive bioluminescence imaging. Metabolite levels in cells and tumor tissue were analyzed using targeted mass spectrometry and MALDI mass spectrometry imaging (MALDI-MSI), respectively. Results: Inducibly silencing EDI3 reduced cell adhesion and colony formation, as well as increased susceptibility to anoikis in HCC1954-luc cells, which was confirmed in SUM190PT cells. No influence on cell migration was observed. Reduced luminescence was seen in lungs and peritoneum of mice injected with cells expressing less EDI3 after tail vein and intraperitoneal injection, respectively, indicative of reduced metastasis. Importantly, mice injected with EDI3-silenced cells survived longer. Closer analysis of the peritoneal organs revealed that silencing EDI3 had no effect on metastatic organotropism but instead reduced metastatic burden. Finally, metabolic analyses revealed significant changes in choline and glycerophospholipid metabolites in cells and in pancreatic metastases in vivo. Conclusions: Reduced metastasis upon silencing supports EDI3’s potential as a treatment target in metastasizing ER-HER2+ breast cancer.Öğe Evaluation of genotoxic effects of C60 fullerene-?-Fe2O3 and multiWall carbon nanotubes-?-Fe2O3 nanoparticles(Kafkas Üniversitesi Veteriner Fakültesi, 2018) Demirci, Özlem; Haşimi, Nesrin; Kılınç, Ersin; Tolan, VeyselThe use of magnetic nanoparticles in nanomedicine applications has increased significantly in recent years. Genotoxic evaluation ofthe nanomaterials used for this purpose is therefore very important. In our study, the genotoxic effect of C60 fullerene-γ-Fe2O3 andmulti-wall carbon nanotubes-γ-Fe2O3 magnetic nanoparticles over a wide concentration range (0.1, 1.0, 5.0, 10.0, 25.0, 50.0, and 100.0µg/plate) was investigated using the Bacterial Reverse Mutation Test. These magnetic nanoparticles did not cause genetic damage toSalmonella typhimurium TA100 and TA98 in the presence and absence of metabolic activation. Due to the rapid increase in the presenceof nanoparticles in our daily lives, mutagenicity and toxicity data related to nanoparticles are quite valuable. For this reason, in vivo andin vitro studies that allow for effective evaluation of these compounds is of the utmost importance.Öğe İmidakloprit ve asetamiprit’in gammarus kischineffensis (Amphipoda:Crustacea) üzerine akut toksik etkisinin değerlendirilmesi(Iğdır Üniversitesi Fen Bilimleri Enstitüsü, 2018) Demirci, ÖzlemBu çalışmada, önemli bir organik ksenobiyotik sınıfı olan neonikotinoit pestisitlerden asetamiprit veimidakloprit’in Gammarus kischineffensis üzerine akut toksik etkisini araştırmak üzere, 48, 72 ve 96 saatlik LC50değerleri belirlenmeye çalışılmıştır. Kullanılan doz aralığında; asetamiprit için LC50 değeri 72 ve 96 saat içinsırasıyla 1.687 ve 0.517 µg L-1; imdakloprit için 48, 72 ve 96 saatteki LC50 değeri 9764.4, 4546.7 ve 1560.9 µg L-1olarak belirlenmiştir.Öğe Investigation of Biological Activities of Some Microalgae Extract Isolated from Kabakli Pond (Diyarbakır) Turkey(Adiyaman University, 2024) Çakmak, Feysel; Özkan, Ahmet İsmail; Haşimi, Nesrin; Demirci, Özlem; Ciniviz, Melike; Varişli, Lokman; Kilinç, ErsinThe antimicrobial, antioxidant and mutagenic activities of methanolic extracts of microalgae species isolated from Kabakli Pond (37° 55' 23N, 40°17' 40E, Diyarbakır) and identified as Chlorella vulgaris Beyerinck and Chroococcus limneticus Lemmermann were investigated. The highest antioxidant activity was observed in the ABTS•+ assay of C. vulgaris (36.63%) and C. limneticus (28.48%) at a concentration of 100 µg/ml concentration. The DPPH and CUPRAC assays showed weak activity. The antioxidant activity did not appear to be significant for either species when compared with the positive controls. C. vulgaris showed high antimicrobial activity with inhibition zone and MIC value against S. aureus. There seemed to be no mutagenic activities; however, C. limneticus showed an effect on the colony structure of S. typhimurium strain TA98. C. vulgaris has a good antimicrobial potential, whereas C. limneticus has relatively weak potential. C. limneticus a relatively has a higher antioxidant activity compared to C. vulgaris, but the activities of both extracts are weak compared to the controls. None of the tested extracts showed mutagenic activity against S. typhimurium TA98 at any of the concentrations. These organisms via different solvents or extraction systems since they may affect various biological systems. © 2024, Adiyaman University. All rights reserved.Öğe Investigation of Biological Activities of Some Microalgae Extract Isolated from Kabakli Pond (Diyarbakır) Turkey(Adıyaman University, 2024) Çakmak, Feysel; Özkan, A. İsmail; Haşimi, Nesrin; Demirci, Özlem; Ciniviz, Melike; Varışlı, Lokman; Kılınç, ErsinThe antimicrobial, antioxidant and mutagenic activities of methanolic extracts of microalgae species isolated from Kabakli Pond (37° 55' 23N, 40°17' 40E, Diyarbakır) and identified as Chlorella vulgaris Beyerinck and Chroococcus limneticus Lemmermann were investigated. The highest antioxidant activity was observed in the ABTS•+ assay of C. vulgaris (36.63%) and C. limneticus (28.48%) at a concentration of 100 µg/ml concentration. The DPPH and CUPRAC assays showed weak activity. The antioxidant activity did not appear to be significant for either species when compared with the positive controls. C. vulgaris showed high antimicrobial activity with inhibition zone and MIC value against S. aureus. There seemed to be no mutagenic activities; however, C. limneticus showed an effect on the colony structure of S. typhimurium strain TA98. C. vulgaris has a good antimicrobial potential, whereas C. limneticus has relatively weak potential. C. limneticus a relatively has a higher antioxidant activity compared to C. vulgaris, but the activities of both extracts are weak compared to the controls. None of the tested extracts showed mutagenic activity against S. typhimurium TA98 at any of the concentrations. These organisms via different solvents or extraction systems since they may affect various biological systems.Öğe Investigation of genotoxic, antimicrobial and antioxidant activities of leaf and flower extracts of Cynara syriaca boiss(Ankara University, 2019) Karaşın, Nurhüda; Tolan, Veysel; Haşimi, Nesrin; Demirci, ÖzlemThe mutagenicity and antimutagenicity of leaves and flower extract of Cynara syriaca Boiss were studied with Ames assay in Salmonella typhimurium TA98 and TA100 strains. While leaves extract did not show any mutagenic effects against all the tester strains with or without metabolic activation, the flower extract showed mutagenic effect against TA98 strain without metabolic activation. On the other hand, it has been observed that the extracts have antimutagenic activity against mutations induced by sodium azide and daunomycin. The antimicrobial activity of extracts was determined by disc diffusion and MIC value. Both of the extracts possess weak antimicrobial activity. Cupric reducing antioxidant capacity (CUPRAC), DPPH free radical scavenging activity, and ABTS radical cation decolorization methods were carried out to determine the antioxidant activity. Among the tested antioxidant methods, the highest antioxidant capacity was determined in ABTS radical cation decolorization assay in which both of the extracts exhibited the best effect. Flower extract exhibited higher activity also in DPPH free radical scavenging.Öğe Response of lettuce to silver nanoparticles under drought conditions(Springer, 2022) Akhoundnejad, Yelderem; Karakaş, Özgür; Demirci, ÖzlemNano-fertilization is an emerging technology to improve agricultural productivity under diverse ecosystems. Our study was conducted to investigate the effects of foliar fertilization of silver nanoparticles (AgNPs) on the growth, enzyme activities and water use efficiency (WUE) of lettuce (Lactuca sativa, L.) under drought conditions. A pot culture study with 4 AgNPs rates x 2 stress levels in a factorial combination of randomized complete block (RCB) design was conducted. The AgNPs levels were 0 (control), 25, 50, 75 and 100 mg/L) were imposed on lettuce seedlings under ambient and simulated drought (similar to 50% field moisture capacity of soil) conditions. Lettuce plant height, total yields, leaf relative water content (RWC), chlorophyll content, membrane injury (MII), glutathione S-transferase (GST), glutathione reductase (GR), carboxylesterase (CaE), total phenolics and flavonoids and WUE were determined and/or calculated. The results showed that GST activity reduced in treatments of AgNPs + stress compared to stressed plants. In treatment of 100 mg L-1 AgNPs + stress, GR activity increased in treatments of 25, 50 and 75 mg L-1 AgNPs, but showed a significant decrease in 100 mg L-1 AgNPs + stress. CaE activity enhanced in 100 mg L(-1 )AgNPs + stress (about 1.55-fold) compared to stressed plants. Total flavonoid and phenolic contents were the highest in 50 mg L-1 AgNPs + stress. It was not obtained significant effects in the WUE rates. In 100 mg L-1 AgNPs, MII rates were the highest, and RWC rates were the lowest. Leaf width, plant height and total yield decreased at doses of AgNPs.Öğe Synthesis and characterization of a polydioxanone-coated dipeptide-functionalized magnetic ?-Fe2O3 nanoparticles-modified PES membrane and its biological applications(MDPI, 2022) Demirci, Özlem; Gonca, Serpil; Tolan, Veysel; Özdemir, Sadin; Dizge, Nadir; Kılınç, ErsinThis work is focused on the synthesis of leucyl-glycine-functionalized γ-Fe2O3 magnetic nanoparticles coated by polydioxanone (γ-Fe2O3-CA-Leu-Gly-PDX) as a polyethersulphone (PES) membrane for biotechnological applications. The physicochemical characteristics were investigated by FT-IR, SEM, XRD, a vibrating sample magnetometer (VSM), and ICP-OES. The present investigation also centered on the several biological activities of γ-Fe2O3-CA-Leu-Gly-PDX. The 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging and metal chelating activity was studied for evaluation of its antioxidant activity potential. It exhibited 100% DPPH radical scavenging and 93.33% metal chelating activity. With applicability to antimicrobial photodynamic therapy, DNA cleavage and antimicrobial activity, the cell viability of γ-Fe2O3-CA-Leu-Gly-PDX was investigated in detail. The γ-Fe2O3-CA-Leu-Gly-PDX demonstrated the significant biofilm inhibition activity as being 81.54% and 86.34% for P. aeruginosa and S. aureus, respectively. Moreover, a novel polyethersulphone nanocomposite membrane incorporated with γ-Fe2O3-CA-Leu-Gly-PDX was prepared. The performance of the γ-Fe2O3-CA-Leu-Gly-PDX-blended polyethersulphone (PES) membrane was investigated by measuring the antifouling and E. coli rejection. The nanocomposite membranes demonstrated remarkable antifouling properties in contrast with the pristine PES when BSA (bovine serum albumin) and E. coli were filtrated. A complete rejection was obtained by the composite membrane. After an application of the membrane study, the modified polyethersulphone (PES) membrane blended with γ-Fe2O3-CA-Leu-Gly-PDX removed 100% of the E. coli.Öğe Toxic effects of glyphosate-based herbicide on melanopsis praemorsa(Adıyaman Üniversitesi, 2020) Demirci, Özlem; Çakmak, Feysel; Özkan, Ahmet İsmailIn the present study, we determined the 24, 48, 72, and 96 h LC50 values for a glyphosatebased commercial herbicide (GBH) for the aquatic snail Melanopsis praemorsa. We examined subacute toxicity responses from M. praemorsa after 30-day exposure to 1/10, 1/5, and 1/2 of the 96 h LC50 value using several biochemical markers. Glutathione reductase (GR) and glutathione S-transferase (GST) activities were significantly inhibited when compared to control after 4 days of GBH exposure. On the twentieth day of exposure, GST and GR activities were inhibited in organisms exposed to both LC50/10 and LC50/5 compared to control. These results showed that chronic GBH exposure inhibited GST, an important detoxifying enzyme. GR, an important oxidative stress marker, was likely inhibited as a result of inhibition of the detoxification mechanism. Keywords: Melanopsis praemorsa; Biomarkers; Glyphosate-based herbicide.
