Search Results
Results 401 - 450 of 1271
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Guha Bibhas - - 2003
Genotoxic effects have been assessed in the fish Oreochromis mossambicus treated separately and conjointly with 0.2% ethylmethane sulphonate (EMS) and 0.05% beta-carotene (BC) during five different time periods (6, 24, 48, 72 and 96 h) by analysis of endpoints such as chromosome aberrations, abnormal red blood cell nuclei, abnormal sperm ...
Adler I-D - - 2003
Nicotine has been tested in the conventional mouse bone marrow assay. Single doses of 1mg/kg bw or 2mg/kg bw were given by oral intubations and bone marrow was sampled at 24h (1mg/kg) or at 6, 12 and 18 h after treatment (2mg/kg). Nicotine treatment did not increase the micronucleus frequencies ...
Kuo Yu-Min - - 2003
The present study was undertaken to assess the ability of 4-hydroxytamoxifen (4-OHT) to alter methamphetamine-induced nigrostriatal dopaminergic toxicity. Three daily doses of 4-OHT (6 micro g/day) effectively attenuated methamphetamine-induced nigrostriatal dopamine depletions in both sexes of intact and gonadectomized C57BL/6 J mice. 4-OHT alone did not alter the dopamine content ...
Otoidobiga Lenli C - - 2003
Bioassays were conducted in 2001 and 2002 to estimate toxicities and dose-response relationships of 24 Bemisica tabaci Gennadius populations to pyriproxifen, acemitaprid, and diafenthiuron. LC50s ranging from 0.014 to 0.096 mgL(-1), 0.60 to 1.3 mgL(-1), and 3.5 to 6.7 mgL(-1) were observed respectively for pyriproxifen, acemitaprid, and diafenthiuron. These LC50s ...
Topashka-Ancheva Margarita - - 2003
The clastogenic effect of total dichloromethane, methanol and water extracts, four bioactive fractions and three individual constituents from Carthamus lanatus aerial parts were evaluated in mice by bone marrow chromosome aberration assay with mitomycin C as positive control. Significant differences in the percentage of aberrant mitosis of the extracts were ...
Arivazhagan S - - 2003
We evaluated the modifying effects of aqueous neem leaf extract on the in vivo clastogenicity of N-methyl-N'-nitro-N-nitrosoguanidine (MNNG), a potent gastric carcinogen by quantitation of micronuclei and chromosomal aberrations in metaphase cells from the bone marrow of male Wistar rats. Intraperitoneal injection of MNNG (40 mg/kg body weight) induced a ...
Roza L - - 2003
Hydroquinone (HQ) occurs in the environment as a result of manmade processes as well as in natural products from plants and animals. The compound has been reported to produce chromosomal effects in some in vivo and in vitro animal models. However, its potential to produce similar effects in human lymphocytes ...
Tomita-Mitchell Aoy - - 2003
The preponderance of G:C to A:T transitions in inherited and somatic human mutations has led to the hypothesis that some of these mutations arise as a result of formation of O(6)-methylguanine in DNA. To test this hypothesis, the fine structure map of N-methyl-N'-nitro-N-nitrosoguanidine (MNNG)-induced mutations was determined in human lymphoblastoid ...
do Céu Silva Maria - - 2003
Phenolic molecules are widely present in the environment and some of them are well known carcinogens. Some phenolic molecules are also genotoxic but the mechanisms involved in this process are not fully understood. We have studied the induction of chromosomal aberrations by phenol, catechol and pyrogallol in V79 cells at ...
Vieira G G - - 2003
The croton oil-induced mouse ear oedema test, acetic acid-induced abdominal writhing, and carrageenan-induced peritonitis were used to study the anti-inflammatory effects of the crude ethanol extract and its alkaloid fraction from Solanum lycocarpum fruits. The alkaloid fraction induced a dose-dependent reduction in ear oedema formation and leukocyte migration, suggesting that ...
Khan P K - - 2003
The genotoxic potentiality of nimesulide was evaluated in vivo in murine bone marrow cells. The human equivalent prophylactic dose of nimesulide (5 mg/kg body wt/day) was given to animals orally, once daily for seven consecutive days. Metaphase chromosome analyses revealed the significant increase in the incidence of chromosomal aberrations with ...
Wang Yunfei - - 2003
This study correlated the extent of induced in vitro chromosomal damage, assessed by the mutagen sensitivity assay, with genotypes of the X-ray repair cross complementing group 1 (XRCC1) gene, which encodes for a base excision repair protein. There are two common polymorphisms that cause amino acid substitutions in XRCC1, one ...
Itoh Toshiaki - - 2003
Transgenic mouse assays have revealed that the mouse intestine, despite its resistance to carcinogenesis, is sensitive to the mutagenicity of some heterocyclic amines (HCAs). Little is known, however, about the level and localization of that sensitivity. We assessed the mutagenicity of four orally administered (20 mg/kg per day for 5 ...
Lehmann Mauricio - - 2003
The genotoxic effects of the anthracycline doxorubicin (DOX) and two of its analogues, epirubicin (EPI) and pirarubicin (THP) were studied using the wing Somatic Mutation and Recombination Test (SMART) in Drosophila melanogaster. These compounds are classified as topoisomerase II (topo II) poisons, acting by stabilizing a topoisomerase II-cleaved DNA complex. ...
Nesina I P - - 2003
We studied changes in the karyotype of transplanted Namalwa cells induced by DNA-damaging antitumor preparations etoposide and fludarabine in subtoxic doses. The relative number of cells containing increased number of chromosomes and the incidence of chromatid aberrations with primary damage to chromosomes 2, 5, 11, 16, and 17 increased. Cytogenetic ...
Degitz Sigmund J - - 2003
Methoprene is an insect juvenile growth hormone mimic, which inhibits pupation and is used for the control of emergent insect pests such as mosquitoes. Researchers have hypothesized that methoprene use in US may be a contributing factor to the recent increase in malformed amphibians. However, little is known concerning the ...
Vernole Patrizia - - 2003
PURPOSE: The mismatch repair (MMR) system plays a major role in mediating the cytotoxicity and clastogenicity of agents generating O(6)-methylguanine in DNA. Loss of MMR has also been associated with tumor cell resistance to the cytotoxic effects of 6-thioguanine and cisplatin and with hypersensitivity to N-(2-chloroethyl)- N'-cyclohexyl- N-nitrosourea (CCNU). The ...
Kirkland David - - 2003
2-Hydroxy-1,4-naphthoquinone (HNQ; Lawsone; CAS 83-72-7) is the principal natural dye ingredient contained in the leaves of Henna (Lawsonia inermis). Published genotoxicity studies on HNQ suggested it was a weak bacterial mutagen for Salmonella typhimurium strain TA98 or was more clearly mutagenic for strain TA 2637, both in the presence of ...
El-Ghamery A A - - 2003
The effects of different treatments with zinc sulfate (Zn(2+)) on the cytology and growth of Nigella sativa and Triticum aestivum were investigated. Five concentrations of zinc sulfate ranging from 5 to 25mg/l were applied for 6, 12, 18, and 24h. The treatments reduced the germination percentages of N. sativa seeds ...
Aydemir Nilüfer - - 2003
In this study, the genotoxic effects of gemcitabine and topotecan were investigated in mouse bone marrow cells using the micronucleus and chromosomal aberration test systems. Gemcitabine increased the frequency of micronuclei, particularly at the median dose for the 24-, 36-, and 48-h sampling intervals. It had cytotoxic effects on the ...
Norppa Hannu - - 2003
As micronuclei (MN) derive from chromosomal fragments and whole chromosomes lagging behind in anaphase, the MN assay can be used to show both clastogenic and aneugenic effects. The distinction between these phenomena is important, since the exposure studied often induces only one type of MN. This particularly concerns the use ...
Jones Eryl - - 2003
Aniline has been reported to be positive in the mouse bone marrow micronucleus test. This finding is inconsistent with its lack of carcinogenicity in this species. Micronuclei can arise by mechanisms that do not involve direct interaction with DNA, e.g. induction of aneuploidy or stimulation of erythropoiesis. However, clastogenic materials ...
Schuler M - - 2003
The cytokinesis block in vitro micronucleus (MN) assay in combination with CREST staining and fluorescence in situ hybridization (FISH) with chromosome-specific DNA probes allows mechanistic information on the induction of numerical chromosomal aberrations to be obtained through a rapid and simple microscopic analysis. These techniques can now be used to ...
Piubelli Giorla Carla - - 2003
The ability of the stink bug (Nezara viridula) to induce and/or increase production of chemical defenses, i.e., flavonoids, in immature seeds of five genotypes of soybean (BR-16, IAC-100, PI 227687, PI 229358, and PI 274454) was investigated under greenhouse and laboratory conditions. Samples from pods of each genotype damaged by ...
Krishnamurthi K - - 2003
OBJECTIVE: Many studies have been conducted in order to evaluate the genotoxicity of chemicals and waste materials, which utilized in vivo test protocols. The use of animals for routine toxicity testing is now questioned by a growing segment of society. METHODS: Keeping the above fact in mind, we have conducted ...
Kim Jong-Gyu - - 2003
A bacterial reverse-mutation assay with Salmonella Typhimurium TA1535, TA1537, TA98, TA100, and TA102 and an in vitro chromosome aberration assay with Chinese hamster lung (CHL) cells were used to investigate the genotoxicity of the methanol extract of Korean soybean paste (doen-jang [dwen-jahng]) and its antigenotoxic activity against aflatoxin B1. The ...
Orsière T - - 2003
The mutagenic (MUT) and chromosome-damaging (CHR) activities of 22 potential antimalarial drugs (5-nitroisoquinoline derivatives) were evaluated by the Salmonella test and the cytokinesis-blocked micronucleus assay (CBMN). The Salmonella mutagenicity test was performed with and without metabolic activation (S9 mix) in S. typhimurium strains TA100 and YG1042 (an overproducing nitroreductase and ...
Weaver Robert P - - 2003
The am3 revertant frequencies (RF) in spleens from male mice transgenic for phiX174 am3, cs70 were analyzed 14 weeks after ethylnitrosourea (ENU) treatment, both by the single burst assay (SBA) and the mixed burst assay (MBA). The mean in vivo (burst size >30/assay plate) revertant frequency (MRF) for the vehicle ...
Shukla Yogeshwer - - 2003
The human diet contains a variety of compounds that exhibit chemopreventive effects towards an array of xenobiotics. In the present study, the antigenotoxic potential of selected dietary constituents including Diallyl sulfide (DAS), Indole-3-carbinol (I3C), Curcumin (CUR), and Black tea polyphenols (BTP) has been evaluated in the Salmonella typhimurium reverse mutation ...
de Lima Patrícia Danielle Lima - - 2003
Hydroxyurea is considered an antineoplastic drug, which also plays an important role in the treatment of sickle cell anemia patients. We evaluated and compared the clastogenic and cytotoxic effects of hydroxyurea, using chromosomal aberrations and mitotic index, respectively, as endpoints. In vitro short-term cultures of lymphocytes were exposed to several ...
Seligmann Igor C - - 2003
The Canova Method (CM) is a homeopathic medicine indicated for the treatment of patients with cancer and for pathologies that involve a depressed immune system, such as AIDS. This product is composed of homeopathic dilutions of Aconitum napellus, Arsenicum album (arsenic trioxide), Bryonia alba, Lachesis muta venom and Thuya occidentalis. ...
Evandri Maria G - - 2003
Polybrominated diphenyl ethers (PBDEs), which are widely used as flame retardants, are considered persistent organic pollutants. To date, the available toxicological data on PBDEs are limited and were primarily obtained by studying technical blends. The present study was undertaken to investigate the genotoxicity of the pure congener 2,2',4,4',5-brominated diphenyl ether ...
Kligerman Andrew D - - 2003
Arsenic is a prevalent human carcinogen whose mutagenicity has not been characterized fully. Exposure to either form of inorganic arsenic, As(III) or As(V), can result in the formation of at least four organic metabolites: monomethylarsonic acid, monomethylarsonous acid (MMA(III)), dimethylarsinic acid, and dimethylarsinous acid (DMA(III)). The methylated trivalent species, as ...
Fortunato Elizabeth A - - 2003
The advent of advanced cell culture and cytogenetics techniques in the 1950s opened a new avenue for research on the pathogenic interactions between animal viruses and their hosts. Studies of many viruses revealed their ability to nonspecifically induce cytogenetic damage to their host cell's chromosomes. However, only three viruses, the ...
Möller Marianne - - 2002
The cytotoxicity and genotoxicity of the antifungal and antimicrobial agent Omadine, i.e. N-hydroxypyridine-2-thione (HOPT), has been investigated in L5178Y mouse lymphoma cells in the dark and under UVA irradiation. Omadine inhibits cell growth and induces micronuclei at concentrations >0.5 microM in the absence of light. At a 0.5-microM concentration, an ...
Lohani M - - 2002
Several experimental and epidermological studies have indicated augmentation of asbestos induced diseases by cigarette smoke by the mechanisms, which are still unknown. To determine whether smoking affects genetic system of the cells and further modifies asbestos induced genotoxicity, whole blood from non-smokers and smokers was exposed to asbestos fibres separately ...
Fach Estelle - - 2002
Environmental and/or occupational exposure to minerals, metals, and fibers can cause lung diseases that may develop years after exposure to the agents. The presence of toxic fibers such as asbestos in the environment plus the continuing development of new mineral or vitreous fibers requires a better understanding of the specific ...
Parry E M - - 2002
A comprehensive evaluation of the genotoxic potential of chemicals requires the assessment of the ability to induce gene mutations and structural chromosome (clastogenic activity) and numerical chromosome (aneugenic activity) aberrations. Aneuploidy is a major cause of human reproductive failure and an important contributor to cancer and it is therefore important ...
Dixon David R - - 2002
The last 25 years have seen major advances in the field of mammalian genotoxicology, particularly with the advent of molecular methods, some of which have spilled over into the relatively new field of eco-genotoxicology, which aims to evaluate the impact of contaminants on the natural biota. Unlike mammalian genotoxicology, where ...
Engelhardt Günter - - 2003
To date, a number of in vivo cytogenetic assays have studied the clastogenicity (chromosome aberrations, micronuclei formation) in bone marrow of rodents exposed to styrene by various routes. The majority of all these cytogenetic experiments yielded negative findings (Scott and Preston, Mutat Res 318:175-203, 1994). Recently published data from a ...
Baciuchka-Palmaro M - - 2002
Increased micronucleated cell rates, dicentric chromosomes, and other chromosomal damages have been reported in lymphocytes of cancer patients prior to the initiation of chemotherapy, and/or radiotherapy. The cause of these chromosomal damages in these lymphocytes remains unclear. In the present work, we investigated whether these micronuclei mainly reflect structural or ...
Ren Zhumei - - 2002
Chromosome aberrations induced by an anti-neoplastic drug, cyclophosphamide (CP) and a bioinsecticide, Bacillus thuringiensis (B.t.) were examined using grasshoppers as an animal model, with injection as the route of exposure. Oxya chinensis (Thunberg), having a small number (2n male symbol =23) of large-sized chromosomes in males, was used for this ...
Kouchi Yasuhide - - 2002
Potassium oxonate (Oxo) is one of three components of S-1, an anticancer drug developed to improve the selective toxicity of 5-fluorouracil (5-FU). Oxo has been shown to reduce gastrointestinal toxicity. In this study, using murine and human granulocyte/macrophage colony forming (mCFU-GM, hCFU-GM) assays, we investigated whether Oxo can reduce 5-FU-induced ...
Hamurcu Zuhal - - 2002
PUVA describes the treatment of patients with psoralens plus an exposure to a source of UV light of 320-400 nm (UVA). Contradictory results have been reported on the chromosomal damage of PUVA when assayed by sister chromatid exchange (SCE) method. Micronucleus (MN) test is used to detect both clastogenic (breaking) ...
Kirsch-Volders Micheline - - 2002
The aim is to review briefly the key questions related to aneuploidy/polyploidy and to compare the advantages and disadvantages of the in vitro micronucleus test to assess aneuploidy/polyploidy in vitro. The key questions that will be addressed, concern the importance of polyploidy for health, and cancer in particular, the mechanisms ...
Fenech Michael - - 2002
We have validated the analysis of nucleoplasmic bridges (NPBs) and nuclear buds as biomarkers of genomic instability within the cytokinesis-block micronucleus assay in long-term lymphocyte cultures. Lymphocytes from 20 subjects were cultured in medium containing 12-120 nM folic acid for 9 days. Binucleate cells were scored for micronuclei (MN), NPBs ...
Sugisawa Ayako - - 2002
We investigated the effects of (-)-epigallocatechin-3-O-gallate (EGCg) on chromosomal damage, which was evaluated by a cytokinesis-block micronucleus (CBMN) assay using WIL2-NS cells. EGCg itself induced chromosomal damage at 100 micromol/L. This damage was due to the production of H(2)O(2) by EGCg. In contrast, EGCg at < 10 micromol/L did not ...
Garaj-Vrhovac Vera - - 2002
The widespread use of pesticides suggests that the evaluation of their genotoxicity should be extended using the different assays available. In the present study we used two standard cytogenetic methods (chromosomal aberration analysis and micronucleus assay) and the Comet assay as a relatively new and powerful technique. The study included ...
Decordier Ilse - - 2002
Two major mechanisms responsible for chromosome segregation errors are non-disjunction and chromosome loss, both leading to aneuploidy. Previous studies in our laboratory showed the existence of thresholds for the induction of chromosome non-disjunction and chromosome loss and the induction of apoptosis by microtubule inhibitors. From a mechanistic point of view ...
Hagger Josephine A - - 2002
The genotoxic, cytotoxic and ontogenetic (embryo-larval) or developmental effects of tri-n-butyltin (TBT), were investigated in Platynereis dumerilii. Following the determination of maximum tolerated dose with regard to ontogenetic effects and mortality, early life stages of P. dumerilii were exposed to a range of TBT concentrations. Subsequently, the embryo-larvae were analysed ...
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