38 research outputs found

    CCD photometric search for peculiar stars in open clusters. VII. Berkeley 11, Berkeley 94, Haffner 15, Lynga 1, NGC 6031, NGC 6405, NGC 6834 and Ruprecht 130

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    The detection of magnetic chemically peculiar (CP2) stars in open clusters of the Milky Way can be used to study the influence of different galactic environments on the (non-)presence of peculiarities, which has to be taken into account in stellar evolution models. Furthermore it is still unknown if the CP2 phenomenon evolves, i.e. does the strength of the peculiarity feature at 5200A, increase or decrease with age. We have observed eight young to intermediate age open clusters in the Delta a photometric system. This intermediate band photometric system samples the depth of the 5200A, flux depression by comparing the flux at the center with the adjacent regions having bandwidths of 110A, to 230A. The Delta a photometric system is most suitable to detect CP2 stars with high efficiency, but is also capable of detecting a small percentage of non-magnetic CP objects. Also, the groups of (metal-weak) lambda Bootis, as well as classical Be/shell stars, can be successfully investigated. This photometric system allows one to determine the age, reddening and distance modulus by fitting isochrones. Among the presented sample of eight galactic clusters, we have detected twenty three CP2, eight Be/Ae and eight metal-weak stars. Another six objects show a peculiar behaviour which is most probably due to a non-membership,variability or duplicity. Fitting isochrones to Delta a photometry yields estimates of the age, reddening and distance that are in excellent agreement with published values

    The CFHT Open Star Cluster Survey. IV. Two Rich, Young Open Star Clusters: NGC 2168 (M35) and NGC 2323 (M50)

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    We continue our study of rich Galactic clusters by presenting deep CCD observations of both NGC 2168 (M35) and NGC 2323 (M50). Both clusters are found to be rich (NGC 2168 contains at least 1000 stars brighter than V = 22 and NGC 2323 contains approximately 2100 stars brighter than our photometric limit of V = 23) and young (age of NGC 2168 = 180 Myrs, age of NGC 2323 = 130 Myrs). The color-magnitude diagrams for the clusters exhibit clear main sequences stretching over 14 magnitudes in the V, B-V plane. Comparing these long main sequences with those of earlier clusters in the survey, as well as with the Hyades, has allowed for accurate distances to be established for each cluster (dist. of NGC 2168 = 912 +/- 70/65 pc, dist. of NGC 2323 = 1000 +/- 81/75 pc). Analysis of the luminosity and mass functions suggest that despite their young ages, both clusters are somewhat dynamically relaxed exhibiting signs of mass-segregation. This is especially interesting in the case of NGC 2323, which has an age of only 1.3 times the dynamical relaxation time. The present photometry is also deep enough to detect all of the white dwarfs in both clusters. We discuss some interesting candidates which may be the remnants of quite massive (M > 5 Mo) progenitor stars. The white dwarf cooling age of NGC 2168 is found to be in good agreement with the main-sequence turn-off age. These objects are potentially very important for setting constraints on the white dwarf initial-final mass relationship and upper mass limit for white dwarf production.Comment: 34 pages, including 12 diagrams and 5 tables. Accepted for publication in AJ. Minor typos correcte

    In vivo genotoxic effects of spiramycin in rat bone marrow cells

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    The aim of this study was to investigate the genotoxic effects of spiramycin which is an effective ingredient of the antibiotic rovamycine in bone marrow cells of rats (Rattus norvegicus var. albinos). The rats were treated with 100, 200, 400 mg/kg bwt/day of spiramycin. Animals were treated with the above concentrations for 7 days and the bone marrow preparations were prepared after 6 and 12 h from the last administration. In 100 mg/kg bwt/day, spiramycin increased the percentages of the abnormal cells and the chromosomal aberration per cell (CA/cell)in the bone marrow cells of rats that were sacrificed after 6 h from the last administration. It could not induce the abnormalities however at the other concentrations (200 and 400 mg/kg bwt/day). The mitotic index (MI) was not decreased by any treatment of spiramycin. Spiramycin did not increase neither the percentage of abnormal cells nor the CA/cell in bone marrow cells of rats which sacrificed after 12 h from the last administration, whereas it generally decreased the MI in this treatment. Spiramycin did not affect the formation of chromosomal gaps

    The in vitro genotoxic and cytotoxic effects of remeron on human peripheral blood lymphocytes

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    PubMedID: 25156279Remeron (Mirtazapine) is an antidepressant drug which exerts its action by blocking presynaptic ?-2-adrenergic receptors and postsynaptic serotonin types 2 and 3 receptors. In this in vitro analysis, human peripheral blood lymphocytes was treated by remeron (10, 25, 40 and 55 g/mL) for 24 hours and 48 hours periods, then it was attempted to study of genotoxic and cytotoxic effects of the substance on human peripheral blood lymphocytes by some tests such as sister chromatid exchange (SCE), chromosomal abnormalities (CA) and micronucleus (MN) tests. Also proliferating effect of the substance was investigated. Remeron didnt significantly cause chromosomal abnormalities and sister chromatid exchange while caused micronucleus at 40 g/mL concentration and 24 h periodic time and increased proliferation index of the both 24 and 48 hours treated cells was decreased in a concentration manner. Also, exposing to the remeron for 24 and 48 hours leaded to a decrease in mitotic index and nucleus division index in the cells by concentration dependent manner. These findings showed that remeron did not have significantly genotoxic effects on human peripheral blood lymphocytes while it showed cytotoxic effects on the cells, which is the first report on genotoxic and cytotoxic properties of remeron. © 2014 Informa Healthcare USA, Inc.FEF2012YL4This study was funded by Cukurova University Research Fund FEF2012YL4

    CHROMOSOMAL-ABERRATIONS IN CULTURED HUMAN-LYMPHOCYTES TREATED WITH MARSHAL AND ITS EFFECTIVE INGREDIENT CARBOSULFAN

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    WOS: A1993MB02300003PubMed ID: 7692285The aim of this study was to investigate the ability of Marshal (insecticide/nematocide) and its effective ingredient Carbosulfan to induce chromosomal aberrations (CA) and other chromosomal abnormalities in human peripheral lymphocytes. Carbosulfan induced the formation of CA at all concentrations (10(-6), 5 x 10(-6), 10(-5), 5 x 10(-5) v/v) and treatment times. Marshal significantly induced the formation of CA at the two highest concentrations 10(-5) and 5 x 10(-5) v/v) at all treatment times. The extent of damage was greatest with Carbosulfan

    Genotoxic effects of 4-methylimidazole on human peripheral lymphocytes in vitro

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    PubMedID: 281406884-Methylimidazole (4-MEI), a heterocyclic organic chemical compound, is widely found in many foods and consumed by people worldwide. In this research, we aimed to investigate the cytotoxic and genotoxic effects of 4-MEI on human lymphocytes. For this purpose, human peripheral blood lymphocytes were treated with four concentrations of 4-MEI (300, 450, 600 and 750 µg/ml) for 24 h and 48 h periods and in vitro sister chromatid exchange (SCE), chromosome aberration (CA) and micronucleus (MN) tests were used. 4-MEI induced SCE in human peripheral lymphocytes at three highest concentrations (450, 600 and 750 µg/ml) in 48 h treatment period. CA and MN were induced in human peripheral lymphocytes at two highest concentrations of 4-MEI (600 and 750 µg/ml) in 24 h and 48 h treatment periods. The highest concentration of 4-MEI (750 µg/ml) induced MN formation more than the positive control MMC in 24 h treatment period. In addition, 4-MEI led to a decrease in MI at the highest concentration (750 µg/ml) in 24 h treatment period and at all concentrations in 48 h treatment period. 4-MEI reduced PI at all concentrations in 24 h treatment period and at all concentrations (expect the lowest) for 48 h treatment period. 4-MEI reduced nuclear division index (NDI) at 24 and 48 h treatment periods, even at the highest two concentrations, decreased more than the positive control MMC. Our results showed that 4-MEI pose a genotoxic and cytotoxic effects for human peripheral lymphocytes. © 2017 Informa UK Limited, trading as Taylor & Francis Group.FEF2013YL5This study was funded by Cukurova University Research Fund (FEF2013YL5)

    The Assessment of Cytotoxicity and Genotoxicity of Mirtazapine in Human Blood Lymphocytes Using Micronucleus Test

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    Introduction: Tetracyclic antidepressants-mirtazapin is one of antidepressants drug that exhibits both noradrenergic and serotonergic activity. It is commonly used to treat major depressive disorder. The genotoxic effect of mirtazapine has not been examined previously. The purpose of this study was to investigate the genotoxic and cytotoxic effects of mirtazapine on human peripheral blood lymphocytes. Methods: The genotoxic and cytotoxic effects of mirtazapine on human peripheral lymphocytes were examined by micronucleus (MN) test. The human lymphocytes were treated with 10, 25, 40 and 55 μg/mL concentrations of mirtazapine for 24 and 48 hours treatment periods. Results: MN formation was not significantly induced at 24- and 48-h treatment periods when compared with control but Nuclear division index (NDI) significantly decreased at all concentrations for two treatment periods. Conclusion: Mirtazapine was not genetoxic but was cytotoxic in human peripheral blood lymphocytes. According to this study mirtazapine has cytotoxic effects on human's cells

    Genotoxic and cytotoxic effect of mirtazapine in human peripheral blood lymphocyte: in vitro study

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    Background and Objective: Mirtazapine is a norepinephrine and serotonergic antidepressant that is used in the theraphy of major depressive disorders. This study was carried out to determine the genotoxic and cytotoxic effect of mirtazapine using chromosome aberration and mitotic index tests in human peripheral blood lymphocytes. Methods: In this descriptive -analytic study genotoxic and cytotoxic effect of mirtazapine at 24 and 48 hours treatment periods on four concentration (10, 25, 40, and 55µg/ml) was performed on peripheral blood lymphocyte of four subjects. Results: Mirtazapine significantly reduced the mitotic index in the all concentrations but it non-significantly increased the chromosome aberration at 24-hours and 48-hours treatment periods. Conclusion: Mirtazapine has cytotoxic effect but it has no genotoxic effect on human lymphocyte

    Assessment of chromosomal aberration in the bone marrow cells of Swiss Albino mice treated by 4-methylimidazole

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    PubMedID: 266349524-Methylimidazole (4-MEI) is formed during the production of certain caramel coloring agents used in many food and drink products. It may also be formed during the cooking, roasting, or other processing of some foods and beverages. So it was unintentionally consumed in worldwide. This study was aimed to investigate the genotoxic and cytotoxic effects of 4-MEI using chromosome aberration (CA) and mitotic index (MI) in Swiss Albino mice. In this research, CA and MI of the mouse bone marrow cells were analyzed after treating the animals with 4-MEI (100, 130 and 160 mg/kg) for 12 h and 24 h treatment times. All data were analyzed using statistical methods. 4-MEI significantly increased the percentage of CAs at all concentrations for 12 h and at highest concentration for 24 h treatment periods. 4-MEI at highest concentration for 12 h and at all concentrations for 24 h decreased the MI in comparison with control. Genotoxic and cytotoxic effects of 4-MEI at 24 h treatment periods were concentration dependent. Consequently, it can be said that 4-MEI have genotoxic and cytotoxic effect in mouse. © 2016 Taylor & Francis
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