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Öğe Bacterial metagenome analysis of Mytilus galloprovincialis collected from Istanbul and Izmir coastal stations of Turkey(Springer, 2020) Bozcal, Elif; Dagdeviren, MelihMytilus galloprovincialis is a marine mollusk belonging to the Bivalvia class. It has been distributed largely in Turkish shores and worldwide aquatic environments. Besides being known as an environmental pollution indicator, it is highly consumed as a food and has a high economic value. Due to their nutritional mechanisms by filtering water, they are affected by pollution in seawater and mussels can host-microbial diversity of environmental origin as well as pathogenic bacteria. Therefore, in this study, bacterial species found in Mediterranean mussels collected from the coastal stations of Istanbul [Rumeli Kavagi (RK), Kucukcekmece (KC)], and Izmir [(Foca (MF), Urla (MU)] were investigated and compared with microbiological and metagenomic analyses. According to microbiological analysis results, 34 mussel-associated Enterobacteriaceae and Vibrionaceae family members were identified. As a result of the culture-independent metagenomic analysis, taxonomic groups for each station were identified and compared based on Operational Taxonomic Unit data. For all stations, the most abundant bacterial genera were the unclassified bacterial genera. the total number of mussel-related total richness identified in all groups was 4889 (RK = 1605; KC = 1930; MF = 1508; and MU = 1125). According to the metagenomic data obtained in this study, different relative amounts of Lachnospiraceae and Bacteroidetes taxa groups were reported for all stations. the pathogenic bacterial genera identified by metagenomic analyses which may be significant for the public health are Arcobacter, Clostridium, Aeromonas, Vibrio, Escherichia_Shigella, Klebsiella, Campylobacter, Helicobacter, Pseudomonas, Morganella, Serratia, Corynebacterium, Enterococcus, Staphylococcus, Yersinia, Mycoplasma, Brucellaceae_unclassified, Pantoea, and Proteus.Öğe Effects of Restraint Stress and Nitric Oxide Synthase Inhibition on Learning and Strategy Preference in Young Adult Male Rats(Aves Yayincilik, 2012) Dagdeviren, Melih; Dogan, Yusuf Hakan; Kanit, LutfiyeObjective: The aim of this study was to investigate the effects of restraint stress and nitric oxide synthase (NOS) inhibition by N omega Nitro-L-Arginine (LNA) on learning and strategy preference. Material and Methods: Rats were randomly divided into four groups (Saline, Saline+Stress, LNA, LNA+Stress). Stress was applied for one hour in glass cylinders during 13 days. One hour after this stress application, water maze experiments were started. Injections (saline 1 ml/kg or 50 mg/kg LNA) were given 10 minutes before each experiment. The platform was kept visible or hidden (on the 4th, 8th, 12th days) at the same position. On the 13th day the platform was located on the opposite quadrant. Results: Saline groups exhibited significantly better performances (F-(1.31)=174.038 p<0.05) at the beginning compared to the NOS inhibited groups. For initial hidden platform days; stress was determined as an impairment factor (F-(1.31)=5.190 p=0.012). At the end, acquisition occurred on both visible and hidden platform days for all groups. There was no significant strategy preference difference between the groups.Development of the stress and NOS inhibition impairments were seen, particularly at different periods of the acquisition. Conclusion: NOS inhibition did not worsen restraint stress-induced learning impairments in rats. Lack of effect may be explained by the antidepressive consequences of NOS inhibition.Öğe Fluvastatin attenuates doxorubicin-induced testicular toxicity in rats by reducing oxidative stress and regulating the blood-testis barrier via mTOR signaling pathway(Sage Publications Ltd, 2019) Gurel, Cevik; Kuscu, Gokce Ceren; Buhur, Aylin; Dagdeviren, Melih; Oltulu, Fatih; Yavasogiu, Nefise Ulku Karabay; Yavasoglu, AltugDoxorubicin (DOX) is an anthracycline derivative antibiotic that still frequently used in the treatment of solid tumors and hematological malignancies. The clinical use of DOX is largely restricted due to acute and chronic renal, cardiac, hematological, and testicular toxicities. Previous studies have indicated that oxidative stress, lipid peroxidation, and apoptosis in germ cells are the main factors in DOX-induced testicular toxicity, but the entire molecular mechanisms that responsible for DOX-induced testicular damage are not yet fully understood. Fluvastatin is a cholesterol-lowering agent that acts by inhibiting hydroxylmethyl glutaryl coenzyme A, the key enzyme for cholesterol biosynthesis. In addition to its cholesterol-lowering effect, fluvastatin showed an antioxidant effect by cleaning hydroxyl and superoxide radicals and this drug could have a protective effect by acting on the mammalian target of rapamycin (mTOR) signal pathway in testicular damage caused by obesity. This study aimed to investigate the possible protective and therapeutic effects of fluvastatin on the DOX-induced testicular toxicity model by histochemical, immunohistochemical, biochemical, and real-time polymerase chain reaction analyses. The present study indicates that fluvastatin may have a protective and therapeutic effect by removing reactive oxygen species and by regulating the mTOR, connexin 43, and matrix metalloproteinase 9 protein and messenger ribonucleic acid expressions, which play an important role in regulating the blood-testis barrier. On the other hand, the use of fluvastatin as a protective/prophylactic agent was found to be more effective than the use of this drug for treatment. In light of this information, fluvastatin may be a candidate agent that can be used to prevent testicular toxicity observed in men receiving DOX treatment.Öğe Induction of Oxidative Stress and Histological Changes in Liver by Subacute Doses of Butyl Cyclohexyl Phthalate(Wiley-Blackwell, 2014) Yavasoglu, N. Ulku Karabay; Koksal, Cinel; Dagdeviren, Melih; Aktug, Huseyin; Yavasoglu, AltugÖğe LuxCDE-luxAB-based promoter reporter system to monitor the Yersinia enterocolitica O:3 gene expression in vivo(Public Library Science, 2017) Bozcal, Elif; Dagdeviren, Melih; Uzel, Atac; Skurnik, MikaelIt is crucial to understand the in vitro and in vivo regulation of the virulence factor genes of bacterial pathogens. In this study, we describe the construction of a versatile reporter system for Yersinia enterocolitica serotype O:3 (YeO3) based on the luxCDABE operon. In strain YeO3-luxCDE we integrated the luciferase substrate biosynthetic genes, luxCDE, into the genome of the bacterium so that the substrate is constitutively produced. The luxAB genes that encode the luciferase enzyme were cloned into a suicide vector to allow cloning of any promoter-containing fragment upstream the genes. When the obtained suicide-construct is mobilized into YeO3-luxCDE bacteria, it integrates into the recipient genome via homologous recombination between the cloned promoter fragment and the genomic promoter sequence and thereby generates a single-copy and stable promoter reporter. Lipopolysaccharide (LPS) O-antigen (O-ag) and outer core hexasaccharide (OC) of YeO3 are virulence factors necessary to colonization of the intestine and establishment of infection. To monitor the activities of the OC and O-ag gene cluster promoters we constructed the reporter strains YeO3-P-ocÖğe Multi-Biomarker Responses After Exposure to Pollution in the Mediterranean Mussels (Mytilus galloprovincialis L.) in the Aegean Coast of Turkey(Springer, 2017) Ozkan, Dilara; Dagdeviren, Melih; Katalay, Selma; Guner, Adem; Yavasoglu, N. Ulku KarabayIn this study, sublethal effects on the Mediterranean mussels (Mytilus galloprovincialis L.) collected from the Aegean coast of Turkey were determined. Enzymes such as glutathione-S-transferase (GST), superoxide dismutase (SOD), catalase (CAT), and acetylcholinesterase (AChE), metallothionein (MT) mRNA expressions, thiobarbituric acid reactive substances (TBARS) contents, determination of 14 heavy metals and micronucleus frequency were selected as multibiomarkers. Results show that heavy metals and an increase in the level of MT gene expression have been determined in tissues of mussels collected from all stations. The GST, SOD and CAT enzymes were increased in mussels of Aliaga and Old Foca, compared to the mussels of Urla, while it was showed inhibition at AChE levels. Extensive LP is determined on mussels of Aliaga. It was determined that mussels in Aliaga region have exposed more oxidative stress than Old Foca and Urla. These biomarkers were carried out for the first time in these stations to assess environmental quality.Öğe Oxidative stress and inflammatory markers in streptozotocin-induced acute and subacute toxicity response(Taylor & Francis Ltd, 2024) Sanci, Ebru; Koksal Karayildirim, Cinel; Dagdeviren, Melih; Yigitturk, Gurkan; Buhur, Aylin; Erbas, Oytun; Yavasoglu, AltugStreptozotocin (STZ) is used as a diabetes-inducing agent in experimental animal studies. However, it is known that STZ-induced diabetic animals show significant increases in oxidative stress parameters and neurodegeneration besides their blood glucose level. In this study, the acute and subacute toxic effects of STZ on the liver, sciatic nerve, and brain tissues were investigated in vivo rat model. Sprague-Dawley rats were divided into two groups; while 50 mg/kg STZ was administered ip to the STZ group, only saline was administered to the control group. After STZ administration, three units (100 U/mL) of subcutaneous insulin glargine were applied daily to prevent the formation of diabetes. At 24 h, 1,2, and 4 weeks after applications, rats from each group were sacrificed and tissues were removed under anesthesia. At the end of the study, compared to the control, a significant decrease in SOD and GST activity and an increase in lipid peroxidation were detected in the liver and sciatic tissues of rats in the STZ-treated group in the first 24h. Considering the TUNEL, NF kappa B, and NOS2 expressions, it was noted that while the effects of STZ on the liver were observed in the acute stage (24h), it had subacute effects on the brain. When apoptosis-related gene expression (Bcl-2, Bax, CASP3, CASP8, CASP9, TNF-alpha) and immunohistochemistry were evaluated, the apoptotic effect of STZ was observed mostly in sciatic nerve tissues. Within the scope of the study, it was revealed that STZ did not only show selective toxicity to pancreatic beta cells but also very toxic to other tissues and organs.Öğe Oxidative stress-induced apoptotic changes after acute exposure to antifouling agent zinc pyrithione (ZnPT) in Mytilus galloprovincialis Lamark (Mediterranean mussels) tissues(Taylor & Francis Ltd, 2022) Katalay, Selma; Guner, Adem; Dagdeviren, Melih; Yigitturk, Gurkan; Yavasoglu, Altug; Gunal, A. Caglan; Yavasoglu, N. Ulku KarabayZinc pyrithione (ZnPT) is one of the components used in antifouling paints and can be an alternative to classical toxic chemicals such as organotin. However, there is still remarkable concern about the environmental safeness of ZnPT due to rapid transchelation and degradation into several metabolites that have their own toxicity. The effect after acute exposure of ZnPT is investigated on Mediterranean mussels exposed to 20 and 40 mu g/L concentrations for 48 and 96 h and antioxidant responses [superoxide dismutase (SOD), and reduced glutathione (GSH)], genotoxicity [micronuclei (MN) frequency], apoptotic and histological changes were determined. Severe histological changes in hepatopancreas and gill tissues of mussels were observed in ZnPT exposed groups due to dose-dependent increase. ZnPT also caused a dose-dependent increase of TUNEL-positive cell count in the mussel tissues, especially in the hepatopancreas. Increasing in SOD activities and decreasing in GSH levels in both ZnPT concentrations compared to the control were observed. MN and binuclei numbers in all exposure groups were significantly increased. The results of the present study demonstrate that acute exposure to ZnPT could cause an adverse effect on mussel tissues at especially higher concentrations.Öğe Synthesis, characterization, toxicity and in vivo imaging of lysine graft polymeric nanoparticles(Springer, 2019) Bakan, Buket; Kayhan, Ceren Turkcan; Karayildirim, Cinel Koksal; Dagdeviren, Melih; Gulcemal, Suleyman; Yildirim, Yeliz; Akgol, Sinan; Yavasoglu, N. Ulku KarabayPolymeric nanoparticles are commonly used in several biological applications. There are limited number of studies on the toxicity and potential effectiveness of polymeric nanoparticles to need for further study on polymer science. The aim of the study was to investigate characterization, in vitro, in vivo toxicity and biological distribution of Lys-graft-p(HEMA) polymeric nanoparticle. The characterization analyses showed that Lys-graft-p(HEMA) had an average size of around 171 nm and zeta potential was -22.6 mV. The sample was recorded from 750 to 4000 cm(-1) in FTIR spectroscopy and the characteristic peaks of stretching band were observed in the spectrum. The polymeric nanoparticle did not show any cytotoxic effect on human embryonic kidney 293 healthy cell line (HEK 293, ATCC-CRL-1573) after 24 and 48 h of exposure. The nanoparticle did not cause mutation effects on Salmonella typhimurium TA 98, TA 100, TA 1535 and TA 1537 strains. In addition, it has not hemolitic activity on rabbit erythrocytes at applied concentration and no lethality was observed with single oral dose toxicity test. FITC-Lys-graft-p(HEMA) were observed on different organs such as liver, kidney, heart, lung and large intestine at 6. hours by in vivo imaging system. These results reveal that Lys-graft-p(HEMA) polymeric nanoparticles can be used as a potential drug carrier system because of its biocompatibility.
