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    Cytotoxicity and DNA interactions of some platinum(II) complexes with substituted benzimidazole ligands
    (Informa Healthcare, 2012) Ozcelik, Azime Berna; Utku, Semra; Gumus, Fatma; Keskin, Ayten Celebi; Acik, Leyla; Yilmaz, Sukran; Ozgungor, Adeviye
    In the present study, four Pt(II) complexes with 2-ethyl (1)/or benzyl (2)/or p-chlorobenzyl (3)/or 2-phenoxymethyl (4) benzimidazole carrier ligands were evaluated for their in vitro cytotoxic activities against the human HeLa cervix, oestrogen receptor-positive MCF-7 breast, and oestrogen receptor-negative MDA-MB 231 breast cancer cell lines. The plasmid DNA interactions and inhibition of the BamHI restriction enzyme activities of the complexes were also studied. Complex 3 was found to be more active than carboplatin for all examined cell lines and comparable with cisplatin, except for the HeLa cell line.
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    Genetic Differentiation of Lactobacillus delbrueckii subsp bulgaricus and Streptococcus thermophilus Strains Isolated from Raw Milk Samples Collected from Different Regions of Turkey
    (Taylor & Francis Inc, 2015) Yilmaz, Remziye; Temiz, Ayhan; Acik, Leyla; Keskin, Ayten Celebi
    Yogurt is a fermented milk product produced by two homofermentative lactic acid bacteria, Lactobacillus delbrueckii subsp. bulgaricus and Streptococcus thermophilus. It is consumed throughout the world as a healthy, nutritional food. In this study, the strains of Lactobacillus and Streptococcus were isolated from raw milk samples collected from different local geographical regions of Turkey. One hundred and thirty isolates were characterized to genus level by classical morphological, physiological and biochemical tests. Twenty six of all isolates were identified as L. delbrueckii subsp. bulgaricus and 47 isolates were identified as S. thermophilus using API 50 CHL system. RAPD-PCR was used to explain molecular characterization and genetic differentiation of a total of 73 strains. The whole cell protein profiles of these strains were tested by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). In this study, all strains were identified by the RAPD-PCR technique to species or strain level. SDS-PAGE was also shown to be an effective method for molecular differentiation all of the strains. Phenotypic identification, RAPD-PCR and SDS-PAGE proved to be informative methods suitable to explain molecular characterization and genetic differentiation of L. delbrueckii subsp. bulgaricus and S. thermophilus strains isolated from raw milk. In the present study, we described an identification system by using RAPD-PCR and SDS-PAGE techniques and used this system for genetic differentiation of L. delbrueckii subsp. bulgaricus and S. thermophilus strains isolated from raw milk. It is believed that these two molecular techniques allow researchers to fill the significant gaps present in our understanding of these organisms by providing a comprehensive view potentially involved in industrially relevant phenotypes from different geographical origin.
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    Genetic Identification For Some Fusarium Spp. Using Random Amplified Polymorphic Dna Polymerase Chain Reaction (Rapd-Pcr) Technique
    (Parlar Scientific Publications (P S P), 2016) Keskin, Ayten Celebi; Acnik, Leyla; Araz, Aydan; Guler, Perihan
    The Fusarium species that is the cause of the disease that we used in our study takes an important place among microfungi that cause disease in agricultural plant species and economic loss. The subgroups and races of this species especially cause diseases with various symptoms on cereals such as wheat, barley, corn and clover, on fruit trees, and garden and ornamental plants. The definition of these microfungi that are pathogens at the genetic material level is important in terms of determining the disease they cause. The aim of the present study was to determine the genetic relationship among twenty isolates of Fusarium spp. (18 Fusarium species) isolated from wheat, maize and clover in Turkey using RAPD technique. In the present study, Random Amplified Polymorphic DNA (RAPD) markers were used to assess the genetic diversity within 20 isolates of Fusarium. RAPD analysis was performed with 16 decamer primers selected from a total of 30 primers. A total of 408 reproducible fragments were amplified by 16 RAPD primers. All the fragments were polymorphic (100%). The size of these fragments ranged from 100 to 3000 bp. The number of bands per primer varied between 14 and 39. Similaritiy indexes were calculated to determine the genetic relationships among these populations and subsequently dendograms based on Unweighted Pair-Group Method using Arithmetic Averages (UPGMA) was derived. Based on DNA finger prints, all isolates of Fusarium were categorized into three major clusters. The results demonstrated that RAPD analysis can be used for assessing the genetic diversity and the relationships among the Fusarium species.
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    Genotoxicity of monosodium glutamate
    (Pergamon-Elsevier Science Ltd, 2016) Ataseven, Nazmiye; Yuzbasioglu, Deniz; Keskin, Ayten Celebi; Unal, Fatma
    Monosodium glutamate (MSG) is one of the most widely used flavor enhancers throughout the world. The aim of this study is to investigate the genotoxic potential of MSG by using chromosome aberrations (CM), sister-chromatid exchanges (SCEs), cytokinesis-blocked micronucleus (CBMN), and random amplified polymorphic DNA-polimerase chain reaction (RAPD-PCR) in cultured human lymphocytes and alkaline comet assays in isolated human lymphocytes, which were incubated with six concentrations (250, 500, 1000, 2000, 4000 and 8000 mu g/mL) of MSG. The result of this study indicated that MSG significantly and dose dependently increased the frequencies of CM, SCE and MN in all treatments and times, compared with control. However, the replication (RI) and nuclear division indices (NDI) were not affected. In this paper, in vitro genotoxic effects of the MSG was also investigated on human peripheral lymphocytes by analysing the RAPD-PCR with arbitrary 10-mer primers. The changes occurring in RAPD profiles after MSG treatment include increase or decrease in band intensity and gain or loss of bands. In the comet assay, this additive caused DNA damage at all concentrations in isolated human lymphocytes after 1-h in vitro exposure. Our results demonstrate that MSG is genotoxic to the human peripheral blood lymphocytes in vitro. (C) 2016 Published by Elsevier Ltd.
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    Synthesis and characterization of polyethyleneimine/silk fibroin/gold nanoparticle nanocomposites: Potential application as a gene carrier in breast cancer cell lines
    (Pergamon-Elsevier Science Ltd, 2023) Tunali, Beste Cagdas; Akturk, Omer; Sahingoz, Durukan; Turk, Mustafa; Keskin, Ayten Celebi
    There is a need in advancing the design of non-viral gene carriers, thus herein using the pulsed laser ablation in liquid (PLAL) technique, polyethyleneimine-capped gold nanoparticles (PEI-AuNPs) were synthesized and then combined with Bombyx mori silk fibroin (SF) to form the nanocomposites (PEI-SF-AuNPs). After the characterization analyses were carried out, PEI-AuNPs and PEI-SF-AuNPs were tested for their in vitro biocompatibility in MCF-7 and MDA-MB231 breast cancer cells. Finally, the transfection capability of the selected group was observed. PEI capping enabled the cationic modification of the AuNP surface and SF reduced the surface charge (from 35 to 4 mV). PEI-AuNPs were highly monodispersed in shape and size (8-9 nm). The nanoparticle group synthesized in 5% (w/v) PEI concentration (PEI-AuNP5) had increased cytotoxicity as compared to the group synthesized in 1% (w/v) PEI concentration (PEI-AuNP1), but the conjugation of SF with PEI-AuNPs alleviated this cytotoxic tendency significantly. The group (PEI-AuNP1) with the most negligible cytotoxicity proved to be successful in the transfection of siRNA analog, i.e., siGLO green transfection indicator. Overall, the PEI-AuNP1 nanocomposites could be suggested as potent siRNA carriers due to the above beneficial properties in genebased breast cancer therapies.
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    Synthesis, Characterization And Dna Interaction Of Novel Platinum(Ii) Complexes Contaning Substituted Benzimidazole Ligands
    (Editura Acad Romane, 2017) Nzeyimana, Abdoul; Utku, Semra; Acik, Leyla; Keskin, Ayten Celebi
    Eight novel Pt(II) complexes corresponding to the following general formula [PtCl2(L-1-L-4)(2)] (C1 -C4) and [PtI2((L1-L4))(2)] (C5-C8) in which 5(6)-chloro/or-methyl-2-H/or-methylbenzimidazole (L-1-L-4) played the key role as carrier ligands were synthesized and characterized by elemental analysis, IR and H-1 NMR. Considering leaving group functions, the anionic ligand iodido and chloro were utilized with the purpose of studying the interaction between the synthesized complexes and pBR322 plasmid DNA by using cisplatin as positive control throughout the Agarose Gel Electrophoresis method. Therefore, looking after plasmid DNA interacting outcomes, synthesized complexes modified the tertiary structure of pBR322 plasmid DNA, and the results showed that the complex C2 ([PtCl2(L-2)(2)]) was highly active compound regarding to all synthesized complexes.
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    Synthesis, in-vitro cytotoxic activity and DNA interactions of new dicarboxylatoplatinum(II) complexes with 2-hydroxymethylbenzimidazole as carrier ligands
    (Wiley, 2014) Utku, Semra; Ozcelik, Azime Berna; Gumus, Fatma; Yilmaz, Sukran; Arsoy, Taibe; Acik, Leyla; Keskin, Ayten Celebi
    ObjectivesThe aim of this study was to investigate the in-vitro cytotoxic activity of new platinum(II) complexes on the human HeLa (ER-), MCF-7 (ER+) and MDA-MB 231 (ER-) cell lines. Furthermore, we investigated plasmid DNA interactions and inhibition of BamHI and HindIII restriction enzyme activity of the complex 1-4,7. MethodsPlatinum(II) complexes were synthesised from precursor complexes of [PtL2Cl2] and [PtL2I2]. Their cytotoxic activity was tested by MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay. Their plasmid DNA interactions and restriction enzyme activities were also investigated using the agarose gel electrophoresis method. Key findingsThe growth inhibitory effect results showed that the cytotoxicity of complex 2 was found to be the most active complex among the synthesised complexes. ConclusionsThe MTT results showed that complex 2 was found to be cytotoxic equal to cisplatin and higher than carboplatin against the MCF-7 and MDA-MB-231 cell lines. Furthermore, the estrogen or progesterone co-treatment slightly increased the cytotoxicity of complex 2, the cisplatin and carboplatin compared with the complex 2 tested alone in 50m concentration. According to plasmid DNA interaction and the restriction studies, complexes 1-4,7 modified the tertiary structure of pBR322 plasmid DNA, and complexes 2-4 prevented enzyme digestion at high concentrations.