Yazar "Yologlu, Ertan" seçeneğine göre listele

Listeleniyor 1 - 4 / 4
  • Küçük Resim Yok
    Öğe
    EFFECTS OF METHYL PARATHION AND COPPER OXYCHLORIDE APPLICATION ON EARTHWORMS (LUMBRICUS TERRESTRIS) IN AN APRICOT ORCHARD
    (Parlar Scientific Publications (P S P), 2013) Yologlu, Ertan; Ozmen, Murat
    In this study, the effects of methyl parathion and copper oxychloride on earthworms were determined using Lumbricus terrestris due to routine pesticide application in an apricot orchard. The study area was divided into three regions. 250 g Folidol M500 (containing methyl parathion) and 1000 g Oxi-cup 50WG (containing copper oxychloride) were separately dissolved in 250 L of water. These solutions were sprayed over apricot trees in the application areas. In these areas, earthworm samples were collected before (control) and at selected days after pesticide application. The collected earthworm samples were used to determine ethoxyresorufin-O-deethylase (EROD), glutathion-S-transferase (GST), carboxylesterase (CaE), and acetylcholinesterase (AChE) activities. The pesticides used in this study adversely affected non-target organisms in the ecosystem. Due to these adverse effects, some enzyme activities were changed in all application areas on the 1st day after applications. It was also decided that the selected biomarkers, EROD, AChE and CaE, are the suitable enzymes to determine the effects of this kind of pesticide exposure.
  • Küçük Resim Yok
    Öğe
    Integrated assessment of biochemical markers in premetamorphic tadpoles of three amphibian species exposed to glyphosate- and methidathion-based pesticides in single and combination forms
    (Pergamon-Elsevier Science Ltd, 2016) Gungordu, Abbas; Uckun, Mirac; Yologlu, Ertan
    In this study, we evaluated the toxic effects of a glyphosate-based herbicide (GBH) and a methidathion-based insecticide (MBI), individually and in combination, on premetamorphic tadpoles of three anuran species: Pelophylax ridibundus, Xenopus laevis, and Bufotes viridis. Based on the determined 96-h LC50 values of each species, the effects of a series of sublethal concentrations of single pesticides and their mixtures after 96-h exposure and also the time-related effects of a high sublethal concentration of each pesticide were evaluated, with determination of changes in selected biomarkers: glutathione S-transferase (GST), glutathione reductase (GR), acetylcholinesterase (AChE), carboxylesterase (CaE), aspartate aminotransferase (AST), and lactate dehydrogenase (LDH). Also, the integrated biomarker response (IBR) was used to assess biomarker responses and quantitatively evaluate toxicological effects. Isozyme differences in CaE inhibition were assessed using native page electrophoresis; results showed that GBH to cause structural changes in the enzyme but not CaE inhibition in P. ridibundus. In general, single MBI and pesticide mixture exposures increased GST activity, while single GBH exposures decreased GST activity in exposed tadpoles. The AChE and CaE activities were inhibited after exposure to all single MBI and pesticide mixtures. Also, higher IBR values and GST, GR, AST, and LDH activities were determined for pesticide mixtures compared with single-pesticide exposure. This situation may be indicative of a synergistic interaction between pesticides and a sign of a more stressful condition. (C) 2015 Elsevier Ltd. All rights reserved.
  • Küçük Resim Yok
    Öğe
    Low concentrations of metal mixture exposures have adverse effects on selected biomarkers of Xenopus laevis tadpoles
    (Elsevier Science Bv, 2015) Yologlu, Ertan; Ozmen, Murat
    Polluted ecosystems may contain mixtures of metals, such that the combinations of metals, even in low concentrations, may cause adverse effects. In the present study, we focused on toxic effects of mixtures of selected metals, the LC50 values, and also their safety limit in aquatic systems imposed by the European legislation using a model organism. Xenopus laevis tadpoles were used as test organisms. They were exposed to metals or their combinations due to 96-h LC50 values. Glutathione S-transferase (GST), glutathione reductase (GR), acetylcholinesterase (AChE), carboxylesterase (CaE), glutathione peroxidase (GPx), and catalase (CAT) levels were evaluated. Metallothionein concentrations were also determined. The LC(50)s for Cd, Pb, and Cu were calculated as 5.81 mg AI/L, 123.05 mg AI/L, and 0.85 mg AI/L, respectively. Low lethality ratios were observed with unary exposure of each metal in lower concentrations. Double or triple combinations of LC50 and LC50/2 concentrations caused 100% lethality with Cd + Cu and Pb + Cd + Cu mixtures, while the Pb + Cu mixture also caused high lethal ratios. The selected enzyme activities were significantly affected by metals or mixtures, and dose-related effects were determined. The metallothionein levels generally increased as related to concentration in unary metals and mixtures. Acceptable limit values of unary metals and mixtures did not significantly change metallothionein levels. The results suggest that oxidative stress-related mechanisms are involved in the toxicity induced by selected metals with combinations of very low concentrations. (C) 2015 Elsevier B.V. All rights reserved.
  • Küçük Resim Yok
    Öğe
    The protective effects of pomegranate juice on lead acetate-induced neurotoxicity in the male rat: A histomorphometric and biochemical study
    (Wiley, 2022) Annac, Ebru; Uckun, Mirac; Ozkaya, Ahmet; Yologlu, Ertan; Pekmez, Hidir; Bulmus, Ozgur; Aydin, Ali
    The purpose of this study was to investigate the potential side-effects of lead acetate (LA), which is toxic to the nerves, blood and muscles, in the rat brain. The neuroprotective effects of pomegranate juice (PJ) against LA exposure were also observed. The experiment involved 28 male Wistar albino rats aged 12 weeks. These were divided into four groups: Control, PJ, LA and LA+PJ. Stereological techniques were employed to determine hippocampal volume in each rat brain. Biochemical investigations and histopathological examinations were also performed. Analysis demonstrated a significant decrease in hippocampal volume in the LA group compared to the control group (p < .05). The stereology results also indicated that PJ has protective effects when compared with the LA and LA+PJ groups. A significant increase was also determined in malondialdehyde (MDA) levels and glutathione S-transferase (GST) activity in the LA group compared to the control group, in contrast to glutathione (GSH) levels and carboxylesterase (CaE) and acetylcholinesterase (AchE) activities. MDA and GST activity decreased significantly in the LA+PJ group compared to the LA group in contrast to GSH levels and CaE and AchE activities. Histopathological examination revealed a number of degenerative changes in the LA group. Exposure to LA adversely affects the hippocampus on the male rat brain. It might also be suggested that PJ may ameliorate these deleterious effects.