Comet Assay: A genotoxicological technique for measuring DNA damage in an individual cell using single-cell gel electrophoresis. Cell DNA fragments assume a "comet with tail" formation on electrophoresis and are detected with an image analysis system. Alkaline assay conditions facilitate sensitive detection of single-strand damage.DNA Damage: Injuries to DNA that introduce deviations from its normal, intact structure and which may, if left unrepaired, result in a MUTATION or a block of DNA REPLICATION. These deviations may be caused by physical or chemical agents and occur by natural or unnatural, introduced circumstances. They include the introduction of illegitimate bases during replication or by deamination or other modification of bases; the loss of a base from the DNA backbone leaving an abasic site; single-strand breaks; double strand breaks; and intrastrand (PYRIMIDINE DIMERS) or interstrand crosslinking. Damage can often be repaired (DNA REPAIR). If the damage is extensive, it can induce APOPTOSIS.Micronucleus Tests: Induction and quantitative measurement of chromosomal damage leading to the formation of micronuclei (MICRONUCLEI, CHROMOSOME-DEFECTIVE) in cells which have been exposed to genotoxic agents or IONIZING RADIATION.Mutagens: Chemical agents that increase the rate of genetic mutation by interfering with the function of nucleic acids. A clastogen is a specific mutagen that causes breaks in chromosomes.Mutagenicity Tests: Tests of chemical substances and physical agents for mutagenic potential. They include microbial, insect, mammalian cell, and whole animal tests.DNA-Formamidopyrimidine Glycosylase: A DNA repair enzyme that is an N-glycosyl hydrolase with specificity for DNA-containing ring-opened N(7)-methylguanine residues.Meteoroids: Any solid objects moving in interplanetary space that are smaller than a planet or asteroid but larger than a molecule. Meteorites are any meteoroid that has fallen to a planetary surface. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)Antimutagenic Agents: Agents that reduce the frequency or rate of spontaneous or induced mutations independently of the mechanism involved.Cosmic Dust: Finely divided solid matter with particle sizes smaller than a micrometeorite, thus with diameters much smaller than a millimeter, moving in interplanetary space. (NASA Thesaurus, 1994)DNA Repair: The reconstruction of a continuous two-stranded DNA molecule without mismatch from a molecule which contained damaged regions. The major repair mechanisms are excision repair, in which defective regions in one strand are excised and resynthesized using the complementary base pairing information in the intact strand; photoreactivation repair, in which the lethal and mutagenic effects of ultraviolet light are eliminated; and post-replication repair, in which the primary lesions are not repaired, but the gaps in one daughter duplex are filled in by incorporation of portions of the other (undamaged) daughter duplex. Excision repair and post-replication repair are sometimes referred to as "dark repair" because they do not require light.DNA Breaks, Single-Stranded: Interruptions in one of the strands of the sugar-phosphate backbone of double-stranded DNA.Lymphocytes: White blood cells formed in the body's lymphoid tissue. The nucleus is round or ovoid with coarse, irregularly clumped chromatin while the cytoplasm is typically pale blue with azurophilic (if any) granules. Most lymphocytes can be classified as either T or B (with subpopulations of each), or NATURAL KILLER CELLS.DNA Breaks: Interruptions in the sugar-phosphate backbone of DNA.Micronuclei, Chromosome-Defective: Defective nuclei produced during the TELOPHASE of MITOSIS or MEIOSIS by lagging CHROMOSOMES or chromosome fragments derived from spontaneous or experimentally induced chromosomal structural changes.Neon: Neon. A noble gas with the atomic symbol Ne, atomic number 10, and atomic weight 20.18. It is found in the earth's crust and atmosphere as an inert, odorless gas and is used in vacuum tubes and incandescent lamps.Gamma Rays: Penetrating, high-energy electromagnetic radiation emitted from atomic nuclei during NUCLEAR DECAY. The range of wavelengths of emitted radiation is between 0.1 - 100 pm which overlaps the shorter, more energetic hard X-RAYS wavelengths. The distinction between gamma rays and X-rays is based on their radiation source.Ethyl Methanesulfonate: An antineoplastic agent with alkylating properties. It also acts as a mutagen by damaging DNA and is used experimentally for that effect.DNA Fragmentation: Splitting the DNA into shorter pieces by endonucleolytic DNA CLEAVAGE at multiple sites. It includes the internucleosomal DNA fragmentation, which along with chromatin condensation, are considered to be the hallmarks of APOPTOSIS.DNA: A deoxyribonucleotide polymer that is the primary genetic material of all cells. Eukaryotic and prokaryotic organisms normally contain DNA in a double-stranded state, yet several important biological processes transiently involve single-stranded regions. DNA, which consists of a polysugar-phosphate backbone possessing projections of purines (adenine and guanine) and pyrimidines (thymine and cytosine), forms a double helix that is held together by hydrogen bonds between these purines and pyrimidines (adenine to thymine and guanine to cytosine).Methyl Methanesulfonate: An alkylating agent in cancer therapy that may also act as a mutagen by interfering with and causing damage to DNA.Leukemia L5178: An experimental lymphocytic leukemia of mice.Dose-Response Relationship, Radiation: The relationship between the dose of administered radiation and the response of the organism or tissue to the radiation.Electrophoresis, Agar Gel: Electrophoresis in which agar or agarose gel is used as the diffusion medium.Oxidative Stress: A disturbance in the prooxidant-antioxidant balance in favor of the former, leading to potential damage. Indicators of oxidative stress include damaged DNA bases, protein oxidation products, and lipid peroxidation products (Sies, Oxidative Stress, 1991, pxv-xvi).DNA Breaks, Double-Stranded: Interruptions in the sugar-phosphate backbone of DNA, across both strands adjacently.Radiation: Emission or propagation of acoustic waves (SOUND), ELECTROMAGNETIC ENERGY waves (such as LIGHT; RADIO WAVES; GAMMA RAYS; or X-RAYS), or a stream of subatomic particles (such as ELECTRONS; NEUTRONS; PROTONS; or ALPHA PARTICLES).Spermatozoa: Mature male germ cells derived from SPERMATIDS. As spermatids move toward the lumen of the SEMINIFEROUS TUBULES, they undergo extensive structural changes including the loss of cytoplasm, condensation of CHROMATIN into the SPERM HEAD, formation of the ACROSOME cap, the SPERM MIDPIECE and the SPERM TAIL that provides motility.Radiation Tolerance: The ability of some cells or tissues to survive lethal doses of IONIZING RADIATION. Tolerance depends on the species, cell type, and physical and chemical variables, including RADIATION-PROTECTIVE AGENTS and RADIATION-SENSITIZING AGENTS.Casearia: A plant genus of the family FLACOURTIACEAE. Members contain casearins which are clerodane type DITERPENES.Hydrogen Peroxide: A strong oxidizing agent used in aqueous solution as a ripening agent, bleach, and topical anti-infective. It is relatively unstable and solutions deteriorate over time unless stabilized by the addition of acetanilide or similar organic materials.Melastomataceae: A plant family of the order Myrtales, subclass Rosidae, class Magnoliopsida composed of tropical plants with parallel-nerved leaves.Deoxyguanosine: A nucleoside consisting of the base guanine and the sugar deoxyribose.Occupational Exposure: The exposure to potentially harmful chemical, physical, or biological agents that occurs as a result of one's occupation.7,8-Dihydro-7,8-dihydroxybenzo(a)pyrene 9,10-oxide: 7,8,8a,9a-Tetrahydrobenzo(10,11)chryseno (3,4-b)oxirene-7,8-diol. A benzopyrene derivative with carcinogenic and mutagenic activity.Radiation, Ionizing: ELECTROMAGNETIC RADIATION or particle radiation (high energy ELEMENTARY PARTICLES) capable of directly or indirectly producing IONS in its passage through matter. The wavelengths of ionizing electromagnetic radiation are equal to or smaller than those of short (far) ultraviolet radiation and include gamma and X-rays.Struthioniformes: An order of flightless birds comprising the ostriches, which naturally inhabit open, low rainfall areas of Africa.Cell Survival: The span of viability of a cell characterized by the capacity to perform certain functions such as metabolism, growth, reproduction, some form of responsiveness, and adaptability.Ethylnitrosourea: A nitrosourea compound with alkylating, carcinogenic, and mutagenic properties.Agrochemicals: Chemicals used in agriculture. These include pesticides, fumigants, fertilizers, plant hormones, steroids, antibiotics, mycotoxins, etc.Antioxidants: Naturally occurring or synthetic substances that inhibit or retard the oxidation of a substance to which it is added. They counteract the harmful and damaging effects of oxidation in animal tissues.Dose-Response Relationship, Drug: The relationship between the dose of an administered drug and the response of the organism to the drug.Medical Secretaries: Individuals responsible for various duties pertaining to the medical office routine.Coke: A residue of coal, left after dry (destructive) distillation, used as a fuel.4-Nitroquinoline-1-oxide: A potent mutagen and carcinogen. This compound and its metabolite 4-HYDROXYAMINOQUINOLINE-1-OXIDE bind to nucleic acids. It inactivates bacteria but not bacteriophage.X-Rays: Penetrating electromagnetic radiation emitted when the inner orbital electrons of an atom are excited and release radiant energy. X-ray wavelengths range from 1 pm to 10 nm. Hard X-rays are the higher energy, shorter wavelength X-rays. Soft x-rays or Grenz rays are less energetic and longer in wavelength. The short wavelength end of the X-ray spectrum overlaps the GAMMA RAYS wavelength range. The distinction between gamma rays and X-rays is based on their radiation source.Particle Accelerators: Devices which accelerate electrically charged atomic or subatomic particles, such as electrons, protons or ions, to high velocities so they have high kinetic energy.Leukocytes: White blood cells. These include granular leukocytes (BASOPHILS; EOSINOPHILS; and NEUTROPHILS) as well as non-granular leukocytes (LYMPHOCYTES and MONOCYTES).Protons: Stable elementary particles having the smallest known positive charge, found in the nuclei of all elements. The proton mass is less than that of a neutron. A proton is the nucleus of the light hydrogen atom, i.e., the hydrogen ion.Proton Therapy: The use of an external beam of PROTONS as radiotherapy.Mouth Mucosa: Lining of the ORAL CAVITY, including mucosa on the GUMS; the PALATE; the LIP; the CHEEK; floor of the mouth; and other structures. The mucosa is generally a nonkeratinized stratified squamous EPITHELIUM covering muscle, bone, or glands but can show varying degree of keratinization at specific locations.Administration, Buccal: Administration of a soluble dosage form between the cheek and gingiva. It may involve direct application of a drug onto the buccal mucosa, as by painting or spraying.

Vitamin E supplementation and oxidative damage to DNA and plasma LDL in type 1 diabetes. (1/1075)

OBJECTIVE: To determine the effect of 400 IU/day of the antioxidant vitamin E on the susceptibility of plasma LDL and lymphocyte DNA to oxidative damage in type 1 diabetes. RESEARCH DESIGN AND METHODS: We studied 42 patients with type 1 diabetes and 31 age- and sex-matched control subjects in a randomized prospective double-blind placebo-controlled trial by using 400 IU/day of oral vitamin E for 8 weeks. Measurements were made of single-strand breaks in lymphocyte DNA at baseline and after hydrogen peroxide-induced stress (comet assay) and of copper-induced LDL oxidization and plasma antioxidant profiles. RESULTS: Plasma LDL and lymphocyte DNA were more resistant to induced oxidative change in the type 1 diabetes group than in control subjects. Vitamin E supplementation reduced LDL oxidizability in the control subjects but not in the type 1 diabetes group and had no effect on oxidative DNA damage in either group. The type 1 diabetes group had a significantly poorer plasma antioxidant profile with lower mean serum concentrations of alpha-tocopherol and most carotenoids than control subjects. CONCLUSIONS: Plasma LDL and lymphocyte DNA appear to be more resistant to oxidative change in type 1 diabetic subjects than in control subjects, and there was no evidence of oxidatively induced DNA or LDL change in type 1 diabetes. This study does not support the hypothesis of oxidative damage in these patients, and a dose of vitamin E (400 IU/day) that reduced LDL oxidative susceptibility in control subjects did not do so in patients with type 1 diabetes.  (+info)

Comet assay application in environmental monitoring: DNA damage in human leukocytes and plant cells in comparison with bacterial and yeast tests. (2/1075)

Urban airborne particulate is a complex mixture of air pollutants, many of which have not been identified. However, short-term mutagenesis tests together with chemicophysical parameter analysis are able to better assess air quality and genotoxic load. The findings of continuous monitoring (January 1991-August 1998) of urban air genotoxicity of a Po Valley town (Italy) on Salmonella typhimurium and Saccharomyces cerevisiae are reported. During this period, various measures (catalytic devices, unleaded fuels, annual vehicle overhaul, etc.) to improve air-dispersed pollutant control were enforced. However, a continuous presence of genotoxic compounds is shown and more qualitative than quantitative changes are evident. We also demonstrate the ability of the Comet assay to detect DNA-damaging agents in airborne particulate samples. We applied the test to human leukocytes and, with major improvements, to plant cells (Allium cepa roots and epigean tissues of Impatiens balsamina). The first findings on human leukocytes confirm the sensitivity of this assay, its peculiarity and its applicability in assessing genotoxicity in environmental samples. The capability of plants to show the response of multicellular organisms to environmental pollutants largely counterbalances a probable lowering in sensitivity. Moreover, application of the Comet test to epigean tissues could be useful in estimating the bioavailability of and genotoxic damage by air pollutants, including volatile compounds (ozone, benzene, nitrogen oxides, etc.) to higher plants.  (+info)

Comet assay of UV-induced DNA damage in retinal pigment epithelial cells. (3/1075)

PURPOSE: The molecular mechanisms mediating photic injury to the retinal pigment epithelial (RPE) cell are not clearly understood. This study examined qualitative and quantitative aspects of DNA damage caused by broadband UVA and UVB radiation in RPE cells. METHODS: Cultured bovine RPE cells were exposed to doses of between 0 and 0.9 J/cm2 UVA or 0 and 0.09 J/cm2 UVB, as either a suspension or as an attached monolayer. The damage to DNA resulting in single-strand breaks was assessed by means of the comet assay in which the damaged DNA migrates out of the nucleus forming a tail, and this was quantified using image analysis. Two measurements were taken: the mean percentage of tail DNA, which reflects the overall level of DNA damage in the group of cells, and the Olive tail moment, which represents the extent of migration and thus the pattern of DNA damage in individual cells. Cells were processed by the comet assay immediately after UV exposure in acute experiments. To study the occurrence of DNA repair, RPE cells were first exposed to UVB and then incubated at 37 degrees C for either 1 or 24 hours before processing for the comet assay. RESULTS: UVA- and UVB-exposed cells showed a mean percentage of tail DNA that was significantly greater than in unexposed cells. Olive tail moment was higher in cells exposed to larger doses of UVB. This parameter also showed a bimodal distribution when assessed 24 hours after exposure to UVB indicating the presence of two distinct subpopulations of cells with small and large tail moments. Cells with very large tail moments were not seen with doses below 0.045 J/cm2. CONCLUSIONS: Relatively low doses of UVA and UVB induce the formation of DNA strand breaks in cultured RPE. The tail moment profiles for cells incubated for 24 hours after UVB irradiation are consistent with the occurrence of DNA repair in most cells exposed to low doses and apoptosis in a subpopulation of the cells exposed to high doses.  (+info)

The bromodeoxyuridine comet assay: detection of maturation of recently replicated DNA in individual cells. (4/1075)

The single-cell gel electrophoresis (Comet) assay is a relatively simple method of measuring DNA single strand breaks and alkali-labile sites in individual cells. We have combined this with bromodeoxyuridine (BrdUrd) labeling of DNA and immunolocalization of the BrdUrd to assess DNA replicative integrity on a single-cell basis. We show that the existence of strand discontinuities in recently replicated domains of DNA, caused during semiconservative replication or exacerbated by the arrest of replicative polymerases at UV irradiation- or chemical-induced lesions, can be detected in individual cells. Data obtained from BrdUrd-Comets are consistent with biochemical data derived with a range of techniques showing that DNA replication involves the creation of strand breaks or gaps adjacent to recently replicated material, and that DNA damage prolongs the duration of such discontinuities where DNA polymerases are stalled opposite lesions (R. T. Johnson et al, The Legacy of Cell Fusion, pp. 50-67, Oxford: Science Publications, 1994; R. B. Painter, J. Mol. Biol., 143: 289-301, 1980.). Compared with standard biochemical techniques, the BrdUrd-Comet assay is simple and suitable for the accurate and automatable assessment of replicative integrity in very small numbers of mammalian cells, such as may be obtained by biopsy.  (+info)

Extremely low frequency pulsed DC electric fields promote neutrophil extension, metabolic resonance and DNA damage when phase-matched with metabolic oscillators. (5/1075)

Application of extremely low frequency pulsed DC electric fields that are frequency- and phase-matched with endogenous metabolic oscillations leads to greatly exaggerated neutrophil extension and metabolic resonance wherein oscillatory NAD(P)H amplitudes are increased. In the presence of a resonant field, migrating cell length grows from 10 to approximately 40 microm, as does the overall length of microfilament assemblies. In contrast, cells stop locomotion and become spherical when exposed to phase-mismatched fields. Although cellular effects were not found to be dependent on electrode type and buffer, they were sensitive to temporal constraints (phase and pulse length) and cell surface charge. We suggest an electromechanical coupling hypothesis wherein applied electric fields and cytoskeletal polymerization forces act together to overcome the surface/cortical tension of neutrophils, thus promoting net cytoskeletal assembly and heightened metabolic amplitudes. Metabolic resonance enhances reactive oxygen metabolic production by neutrophils. Furthermore, cellular DNA damage was observed after prolonged metabolic resonance using both single cell gel electrophoresis ('comet' assay) and 3'-OH DNA labeling using terminal deoxynucleotidyl transferase. These results provide insights into transmembrane signal processing and cell interactions with weak electric fields.  (+info)

DNA damage induced by 3,3'-dimethoxybenzidine in liver and urinary bladder cells of rats and humans. (6/1075)

3,3'-Dimethoxybenzidine (DMB), a congener of benzidine used in the dye industry and previously found to be carcinogenic in rats, was evaluated for its genotoxic activity in primary cultures of rat and human hepatocytes and of cells from human urinary bladder mucosa, as well as in liver and bladder mucosa of intact rats. A similar modest dose-dependent frequency of DNA fragmentation was revealed by the alkaline elution technique in metabolically competent primary cultures of both rat and human hepatocytes exposed for 20 h to subtoxic DMB concentrations ranging from 56 to 180 microM. Replicating rat hepatocytes displayed a modest increase in the frequency of micronucleated cells after a 48-h exposure to 100 and 180 microM concentrations. In primary cultures of human urinary bladder mucosa cells exposed for 20 h to 100 and 180 microM DMB, the Comet assay revealed a clear-cut increase of DNA fragmentation. In rats given one-half LD50 of DMB as a single oral dose, the GSH level was reduced in both the liver and urinary bladder mucosa, whereas DNA fragmentation was detected only in the bladder mucosa. Taken as a whole, these results suggest that DMB should be considered a potentially genotoxic chemical in both rats and humans; the selective effect on the rat urinary bladder might be the consequence of pharmacokinetic behavior.  (+info)

Induction of genotoxicity by cadmium chloride inhalation in several organs of CD-1 mice. (7/1075)

In recent years, the concentration of metals in the environment has increased significantly. Metal compounds, as a group, are among the best-documented human carcinogens, but the mechanisms by which they act are not completely understood. In the present study a cadmium inhalation model in mice was implemented in order to detect the induction of genotoxic damage as single-strand breaks and alkali-labile sites in several organs (nasal epithelial cells, lung, whole blood, liver, kidney, bone marrow, brain and testicle) using the single cell gel electrophoresis (SCGE) or Comet assay. We found differences among the studied organs after a single and subsequent inhalations: in the organs analyzed we observed that major DNA damage was induced after a single inhalation; in subsequent inhalations there was a tendency to maintain the same magnitude of damage or in some cases it decreased. A correlation between length of exposure, DNA damage and metal tissue concentration was found. These results suggest that cadmium chloride inhalation induces systemic DNA damage; some organs showed less damage than others (liver, brain, etc.) and this finding could be as a consequence of the capacity to remove the damage induced by long periods of exposure, possibly because of the induction of detoxifying mechanisms such as induction of metallothionein.  (+info)

Lymphocyte lycopene concentration and DNA protection from oxidative damage is increased in women after a short period of tomato consumption. (8/1075)

Several epidemiologic studies have suggested a role of tomato products in protecting against cancer and chronic diseases. In nine adult women, we evaluated whether the consumption of 25 g tomato puree (containing 7 mg lycopene and 0.3 mg beta-carotene) for 14 consecutive days increased plasma and lymphocyte carotenoid concentration and whether this was related to an improvement in lymphocyte resistance to an oxidative stress (500 micromol/L hydrogen peroxide for 5 min). Before and after the period of tomato intake, carotenoid concentrations were analyzed by HPLC and lymphocyte resistance to oxidative stress by the Comet assay, which detects DNA strand breaks. Intake of tomato puree increased plasma (P <0.001) and lymphocyte (P<0.005) lycopene concentration and reduced lymphocyte DNA damage by approximately 50% (P<0.0001). Beta-carotene concentration increased in plasma (P<0.05) but not in lymphocytes after tomato puree consumption. An inverse relationship was found between plasma lycopene concentration (r = -0.82, P<0.0001) and lymphocyte lycopene concentration (r = -0.62, P<0.01) and the oxidative DNA damage. In conclusion, small amounts of tomato puree added to the diet over a short period can increase carotenoid concentrations and the resistance of lymphocytes to oxidative stress.  (+info)

The Comet Assay, also called single cell gel electrophoresis (SCGE), is a sensitive and rapid technique for quantifying and analyzing DNA damage in individual cells.
Recently, investigators at Universität Ulm have been investigating the low molecular weight DNA diffusion assay (LMW assay) to measure cytotoxicity in comet assays.. The comet assay is a well-established in vitro and in vivo genotoxicity test. However, there has always been concern that the comet assay (as with all DNA strand break assays) may possibly detect exposure-related cytotoxicity rather than genotoxic effects. This is because DNA degradation is frequently involved in processes leading to cell death. Concurrent measures for cytotoxicity are required for standard genotoxicity testing to assess genotoxicity and to address possible effects of cytotoxicity in comet assay data interpretation.. Typically, histopathology has been accepted as a suitable cytotoxicity detection method when using the in vivo comet assay. By looking at the histology, levels of necrosis and apoptosis can be determined. However, there are other assays available for assessing cytotoxicity.. Here, the LMW assay has ...
Taking into account that there are controversial antioxidative effects of inhalational anesthetics isoflurane and sevoflurane and absence of comparison of genotoxicity of both anesthetics in animal model, the aim of this study was to compare DNA damage and antioxidant status in Wistar rats exposed to a single time to isoflurane or sevoflurane. The alkaline single-cell gel electrophoresis assay (comet assay) was performed in order to evaluate DNA damage in whole blood cells of control animals (unexposed; n = 6) and those exposed to 2% isoflurane (n = 6) or 4% sevoflurane (n = 6) for 120 min. Plasma antioxidant status was determined by 3( 4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. There was no statistically significant difference between isoflurane and sevoflurane groups regarding hemodynamic and temperature variables (P > 0.05). Sevoflurane significantly increased DNA damage compared to unexposed animals (P = 0.02). In addition, Wistar rats anesthetized with ...
Self-assembly systems (SAS) mainly consist of micelles, and liposomes are the classes of Nano Drug Delivery Systems with superior properties compared to traditional therapeutics in targeting cancer tumors. All commercially available nano-formulations of chemotherapeutics currently consist of SAS. According to our knowledge, a specific toxicity comparison based on material differences has not yet been performed. The purpose of this study was to evaluate and compare the toxicity of two SAS consisting of Sterically Stabilized Micelles (SSM) made of a lipid-based amphiphilic distearoyl-sn-glycero-phosphatidylethanolamine-polyethylene glycol (PEG)-2000 and a polymeric micelle (PM) consisting of Y-shape amphiphilic block copolymer, synthesized using poly ε-caprolactone and PEG. The mechanism of cytotoxicity and genotoxicity of micelles on L-929 healthy mouse fibroblast cells was assessed using Sulforhodamine-B, WST-1, Acridine Orange/Ethidium Bromide and alkaline single-cell gel electrophoresis assays.
Article Effects of proton beams from the folded tandem ion accelerator on DNA damage in mouse leukocytes using the comet assay. Single cell gel electrophoresis or the comet assay is a sensitive technique to quantify different types of DNA damage, e.g...
Human dermal fibroblasts (HDFs) are a potential source of somatic cells for genetic manipulation and tissue engineering. Confirmation of cytogenetic stability of these cells is an essential step for cell nuclear transfer and generation of a suitable and functional induced pluripotent stem cells line. HDF cells were isolated and cultured from human foreskin samples. Cytogenetic stability of these cells was evaluated in early (3-4) and late (10-15) passages using karyotype test and alkaline comet assay techniques. HDF cells in early and late passages showed normal karyotype but by comet assay abnormality and DNA damages in late passages of HDFs were observed. Also, the parameters of alkaline comet assay in early passages of HDFs compared with late passages and positive control groups more significantly were different (p , 0.05). These findings indicate that single-strand breaks or DNA damage after many passages may have occurred in HDF cells. Our results demonstrate that only early passages of HDF ...
Nitric oxide (NO) as well as its donors has been shown to generate mutation and DNA damage in in vitro assays. The objective of this study was to identify that DNA single-strand breaks (SSBs) could be elicited by NO, not only in vitro but also in vivo. The alkaline single-cell gel electrophoresis (SCGE) was performed to examine the DNA damage in g12 cells and the cells isolated from the organs of mice exposed to sodium nitroprusside (SNP). A modified method, in which neither collagenase nor trypsin was necessary, was used to prepare the single-cell suspension isolated from organs of mice. Results showed that the exposure of g12 cells to 0.13-0.5 mu mol/ml SNP with S9 for 1 h induced a concentration-dependent increase in DNA SSBs in g12 cells. The significant increase in DNA migration and comet frequency has appeared in the cells isolated from the spleen, thymus, and peritoneal macrophages of mice after injecting i.p. SNP in the dosage range of 0.67-6.0 mg/kg b.wt for 1 h. However, no obvious ...
The economy of the state of Tabasco is based on oil extraction. However, this imposes major effects to the environment and communities. Examples are the Polycyclic Aromatic Hydrocarbons (PAHs) that may be found in the soil, water and sediment of the region. Their volatility makes them available to living beings and results in genotoxic activity. The purpose of this study was to quantify the levels of PAHs in the air at several points in the state, and to analyze their relationship with possible damage to DNA on local inhabitants. Single Cell Gel Electrophoresis Assay (Comet Assay) was applied to peripheral blood lymphocytes of five groups of children between six and 15 years of age. PAH samples were analyzed following US/EPA TO-13-A method. Results indicated the presence in the air of most of the 16 PAHs considered as high priority by EPA, some of which have been reported with carcinogenic activity. Differences (p
This protocol details the experimental procedure for performing the comet assay, a very sensitive DNA break assay based on single cell gel electrophoresis.The analysis of DNA strand breaks, both single- and double-strand breaks (SSBs and DSBs, respectively), was performed in immune resp...
Morphological transformation of C3H/M2 mouse fibroblasts by, and genotoxicity of, extracts of human milk. Breast cancer may be initiated by environmental/dietary agents and human milk may act as an ex vivo indicator of in vivo exposure of mammary epithelial cells to genotoxins. Extracts of human milk from UK-resident women (n = 7) were tested for their abilities to morphologically transform C3H/M2 mouse fibroblasts. Genotoxicities were assessed in the Salmonella typhimurium reverse-mutation assay in the presence of S9 using strains TA1538 and YG1019, and in metabolically-competent human MCL-5 cells with the micronucleus and with the alkaline single cell gel electrophoresis (comet) assays. Two of the seven extracts were inactive in the transformation assay both in the presence or absence of S9, two appeared to be equally transforming either in the presence or absence of S9, and two other extracts induced increased transformation frequencies in the presence of S9. A seventh extract, tested only in ...
Pro-carcinogens, such as benzoapyrene (BaP), that are exogenous ligands of the aromatic hydrocarbon receptor may influence the susceptibility of target-cell populations through the up-regulation of cytochrome P450 (CYP) mixed function oxidases. We examined whether the growth kinetics of MCF-7 cells might determine the level of up-regulation of CYP1A1, CYP1A2 or CYP1B1 by BaP, and whether this could then influence subsequent levels of DNA damage. Cell cultures manipulated to be G0/G1-phase concentrated, S-phase concentrated or G2/M-phase concentrated were treated with BaP and the expression levels of CYP1A1, CYP1A2, CYP1B1, cyclin-dependent kinase inhibitor 1A CDKN1A (P21WAF1/CIP1), B-cell leukaemia/lymphoma-2 (BCL-2), and Bcl-2-associated X levels were determined. Levels of DNA damage were measured as DNA single-strand breaks (SSBs) by the alkaline single-cell gel electrophoresis (comet) assay or as DNA adducts by 32P-postlabelling analysis. BaP-induced up-regulation of CYP1A1 was ...
Ecology affects human organism by causing breaks in DNA and, therefore, induce mutations and malignant cell formation. Comet assay is a quantitative method that allows to measure DNA damage in eukaryotic cells (Liao, McNutt, & Zhu, 2009). This method is widely used in areas, such as human biomonitoring, genotoxicology, and ecology. Comet assay is also called a single-cell gel electrophoresis. Thus, the products of electrophoresis are analyzed under the fluorescent light, which makes it similar to comets. DNA strand breaks are detected by comparing the intensity of the comet tail relative to the head (Collins, 2004). Probiotics containing Lactobacillus rhamnosus were used, as Lactobacilli probiotics were found to be safe and effective against urogenital diseases, food hypersensitivity, and dental caries (Lebeer, Vanderleyden, & De Keersmaeckler, 2008). The aim of the research was to study DNA protector mechanism for three probiotic products, containing L. rhamnosus ...
Within the last decade, the comet assay has been used with increasing popularity to investigate the level of DNA damage in terms of strand breaks and alkaline labile sites in biomonitoring studies. The assay is easily performed on WBCs and has been included in a wide range of biomonitoring studies of occupational exposures encompassing styrene, vinyl chloride, 1,3-butadiene, pesticides, hair dyes, antineoplastic agents, organic solvents, sewage and waste materials, wood dust, and ionizing radiation. Eleven of the occupational studies were positive, whereas seven were negative. Notably, the negative studies appeared to have less power than the positive studies. Also, there were poor dose-response relationships in many of the biomonitoring studies. Many factors have been reported to produce effects by the comet assay, e.g., age, air pollution exposure, diet, exercise, gender, infection, residential radon exposure, smoking, and season. Until now, the use of the comet assay has been hampered by the ...
Comet Assay IV combines accurate, repeatable results with powerful data processing and comprehensive presentation. Once you have obtained your results, you can easily process them using the Spreadsheet Generator, which is included free with every Comet Assay IV system.. The Spreadsheet Generator is an application built in Excel for drawing graphs, tabulating data and calculating statistics from your Comet Assay IV results. Because it is built in Excel, it can easily be customised using any of Excels standard functions and features.. ...
Oxidatively damaged DNA is thought to be important in both the initiation and development of bladder carcinoma. Phytochemical compounds are thought to promote optimal health, partly via their antioxidant effects in protecting cellular components against damaging free radicals. The objective of this study is to assess the effect of a standardised bilberry extract, mirtoselect, on the level of endogenous and induced oxidatively damaged DNA in bladder cancer cells, as assessed by the Comet assay. The Comet assay, also known as single-cell gel electrophoresis, represents a simple method for measuring DNA strand break damage in eukaryotic cells. The sensitivity and specificity of the assay is greatly enhanced by the addition of bacterial repair endonucleases that recognise specific types of damage in the DNA and converts these lesions into additional DNA breaks. - Studies of mirtoselect against three bladder cancer cell lines (RT112, RT4 and HT1376) have shown significant antiproliferative activities ...
TY - JOUR. T1 - DNA damage and breast cancer risk. AU - Smith, Tasha R.. AU - Miller, Mark S.. AU - Lohman, Kurt K.. AU - Case, L. Douglas. AU - Hu, Jennifer H.. PY - 2003/5/1. Y1 - 2003/5/1. N2 - To evaluate whether deficient DNA repair contributes to elevated DNA damage and breast carcinogenesis, we used the comet assay (single-cell alkaline gel electrophoresis) to measure the levels of DNA damage in peripheral lymphocytes from 70 breast cancer cases and 70 controls. DNA damage, measured as the comet tail moment, was not influenced by age, family history (FH), age at menarche, age at first birth or parity. The results showed that cancer cases had significantly higher DNA damage compared with controls; the comet tail moments (mean ± SD) for cases and controls were: 10.78 ± 3.63 and 6.86 ± 2.76 (P , 0.001) for DNA damage at baseline (DB), 21.24 ± 4.88 and 14.97 ± 4.18 (P , 0.001) for DNA damage after exposure to 6 Gy of ionizing radiation (DIR), and 14.76 ± 5.35 and 9.75 ± 3.35 (P , ...
The in vivo genotoxic activity of two inorganic lead compounds was studied in Drosophila melanogaster by measurement of two different genetic endpoints. We used the wing-spot test and the comet assay. The comet assay was conducted with larval haemocytes. The results from the wing-spot test showed that neither lead chloride, PbCl2, nor lead nitrate, Pb(NO3)2, were able to induce significant increases in the frequency of mutant spots. In addition, the combined treatments with gamma-radiation and PbCl2 or Pb(NO3)2 did not show significant variations in the frequency of the three categories of mutant spots recorded, compared with the frequency induced by gamma-radiation alone. This seems to indicate that the lead compounds tested do not interact with the repair of the genetic damage induced by ionizing radiation. When the lead compounds were evaluated in the in vivo comet assay with haemocytes, Pb(NO3)2 was effective in inducing significant increases of DNA damage with a direct dose-response ...
Those who defend the planet ignore comets, and its due to wrong perception that comets cant be stopped. Its difficult to track the ice bodies as said by Nuth, but we can prevent it if we get prepared.. Get the Free Tracker App to find 2018 NES Classic in Stock. Comets are dangerous. The research reveals that its easy to deal with asteroids, because they are common. Its easy to detect NEAs, Near Earth Asteroids than comets, because NEAs are just like our planet. But, comets exist deep in the external solar system, so they are difficult to detect. According to scientists, the Halley comet revolves around sun once in every 75 years.. According to Nuth, comets suddenly appear from nowhere. He said that comet named Siding Spring appeared in 2013 and 2014 striking Mars, and both were dangerous. A space aircraft can destroy comet, but it takes 5 years to prepare a spacecraft, said by Nuth in AGU conference. Comet is larger than NEAs, so they strike the earth at high velocity.. On the contrary, NEA ...
Seven flavonoids were isolated from Eremosparton songoricum (Litv) Vass and their antioxidation actions were examined. To investigate protective ability against DNA damage induced by H2O2, human peripheral blood mononuclear cells (PBMCs) were incubated with 5-hydroxy-7,4′-dimethoxyflavone,5,7-dihydroxy-3′,4′-dimethoxyflavone, acacetin, chrysoeriol, pedalitin, flavogadorinin and 5,7,4′-trihydroxy-3′-methoxyflavone-4′-O-D-glucoside separately and then treated by H2O2. The percentage of damaged cells were determined by single-cell gel electrophoresis. To examine their inhibition of lipid peroxidation, the compounds were incubated with rat microsomes and the reaction was initiated by Fe2+/Vc. The lipid peroxidation product thiobarbituric acid reactive substances (TBARS) was determined. The result showed most of flavonoids had concentration-dependent antioxdative activities. The relationship of antioxidation and the structure is discussed.
Just download these files into the extras folder of Celestia and you are ready to go (despite the comet only being magnitude 10, Celestia exagerates the comets tail and brightness, it does this for all comets around perihelion, but it makes them easy to find). You can get a whole passel of comet orbitals from the Celestia motherlode comet section, but be aware that the 164P-Christensen obits here are the old, pre-recovery orbits (also, if you load in the full catalog of comets, they sky will be taken up by comet orbits, best to use that as a resource to extract comets as you need them ...
The genotoxic effects of 2.45 GHz microwave (MW) radiation on the testis and ovary of Sprague Dawley rats was investigated. The animals were exposed to varying levels of specific absorption rate (SAR) of 0 (control), 0.48, 0.95, 1.43, 1.91, 2.39, 2.90, 3.40, 3.80 and 4.30 Wkg-1 , for 10 min. The induction of DNA damages was assessed using DNA direct amplification of length polymorphisms (DALP) and validated with single cell gel electrophoresis (SCGE) comet assay for same cells at SAR 2.39 Wkg-1 . Potential damage at the organ level was assessed by histopathological study. The results show significant differences in the Olive moment and % DNA in the blood of the exposed animals when compared with the control (p , 0.05). Hyperchromasia was observed in the ovary of the animals exposed to MW radiation. Also, there was reduction in the number of germ cells and cell disorganization in the testis of exposed group with increasing SARs. These results suggest that MW radiation has the potential to affect ...
The genotoxic effects of 2.45 GHz microwave (MW) radiation on the testis and ovary of Sprague Dawley rats was investigated. The animals were exposed to varying levels of specific absorption rate (SAR) of 0 (control), 0.48, 0.95, 1.43, 1.91, 2.39, 2.90, 3.40, 3.80 and 4.30 Wkg-1 , for 10 min. The induction of DNA damages was assessed using DNA direct amplification of length polymorphisms (DALP) and validated with single cell gel electrophoresis (SCGE) comet assay for same cells at SAR 2.39 Wkg-1 . Potential damage at the organ level was assessed by histopathological study. The results show significant differences in the Olive moment and % DNA in the blood of the exposed animals when compared with the control (p , 0.05). Hyperchromasia was observed in the ovary of the animals exposed to MW radiation. Also, there was reduction in the number of germ cells and cell disorganization in the testis of exposed group with increasing SARs. These results suggest that MW radiation has the potential to affect ...
diversity among more than two dozen comets observed to date.. Tony Farnham (University of Maryland, College Park, Maryland) is an astronomer who studies the dynamics of cometary nuclei and the interrelationship between a comets nucleus and its coma. He was a member of the Science teams for the Deep Impact mission to comet Tempel 1, the extended mission (DIXI) to comet Hartley 2, and the Stardust-Next mission that returned to comet Tempel 1. He also led one of the teams that performed the analysis of the dust hazards posed by comet Siding Spring during its close approach to Mars.. Kelly Fast (NASA Headquarters) [Bio coming soon...] Yan Fernandez (University of Central Florida, Orlando, FL) is an astronomer who has been studying comets and asteroids since the mid-1990s. He has studied comets, asteroids, Trojans, Centaurs, and small moons at IR, visible, and radio wavelengths for over ten years with the goal of determining their physical and compositional properties. He is the PI of the Spitzer ...
The genotoxicity of jet propulsion fuel 8 (JP-8) was assessed in the leukocytes of archived blood specimens from U.S. Air Force personnel using the comet assay. No differences in mean comet assay measurements were found between low, moderate, and high exposure groups before or after a 4 hour work shift. Before the work shift, mean tail DNA and mean tail (Olive) moment increased as the concentratio
A comet is an icy small Solar System body that, when passing close to the Sun, warms and begins to release gases, a process called outgassing. This produces a visible atmosphere or coma, and sometimes also a tail. These phenomena are due to the effects of solar radiation and the solar wind acting upon the nucleus of the comet. Comet nuclei range from a few hundred metres to tens of kilometres across and are composed of loose collections of ice, dust, and small rocky particles. The coma may be up to 15 times the Earths diameter, while the tail may stretch one astronomical unit. If sufficiently bright, a comet may be seen from the Earth without the aid of a telescope and may subtend an arc of 30° (60 Moons) across the sky. Comets have been observed and recorded since ancient times by many cultures.. Comets usually have highly eccentric elliptical orbits, and they have a wide range of orbital periods, ranging from several years to potentially several millions of years. Short-period comets ...
879 Polycyclic aromatic hydrocarbons (PAHs) are environmental pollutants implicated in the causation of human lung cancer. One pathway of metabolic activation that yields reactive oxygen species (ROS) involves the oxidation of PAH trans-dihydrodiols by aldo-keto reductases (AKRs) to yield reactive and redox-active o-quinones, which can cause oxidative DNA damage (e.g. 8-oxo-dGuo). Evidence for this pathway in lung cells has been hampered by the difficulty in detecting 8-oxo-dGuo levels reliably in intact cells. We used the single cell gel electrophoresis (Comet) assay to detect DNA strand breaks in human lung adenocarcinoma (A549) cells (which express AKR1A1 and AKR1C isoforms) following treatment with BP-7,8-diol (AKR substrate), and BP-7,8-dione (AKR-product) and (+)-anti-BPDE. In the presence of DNA synthesis inhibitors (cytosine arabinoside and hydroxyurea) all three PAH metabolites produced significant DNA strand breaks in a concentration-dependent manner. Inclusion of ROS scavengers ...
The comet assay is a sensitive, well established technique for quantifying DNA damage in eukaryotic cells. Compatible with the detection of a wide range of DNA damaging agents, its principle consists in migration of fragmented DNA in an electrophoresis gel (damaged DNA forming the tail of the comet), while intact DNA moves at a slower rate (head of the comet). The percentage of fragmented DNA in the comet tail is a direct measure of DNA damage.. ...
These high cliffs occur on the surface of a comet. They were discovered to be part of the dark nucleus of Comet Churyumov-Gerasimenko (CG) by Rosetta, a robotic spacecraft launched by ESA which began orbiting the comet in early August. The ragged cliffs, as featured here, were imaged by Rosetta about two weeks ago. Although towering about one kilometer high, the low surface gravity of Comet CG would likely make a jump from the cliffs, by a human, survivable. At the foot of the cliffs is relatively smooth terrain dotted with boulders as large as 20 meters across. Data from Rosetta indicates that the ice in Comet CG has a significantly different deuterium fraction -- and hence likely a different origin -- than the water in Earths oceans. The Rosetta spacecraft is scheduled to continue to accompany the comet as it makes its closest approach to the Sun in 2015 August. via NASA http://ift.tt/ ...
Hydrogen, Lead, Ability, Alkaline Comet Assay, Alkylation, Alkylators, Blood, Cancer, Cell, Cells, Chromatography, Comet Assay, Concentration, Concentrations, DNA, DNA Damage, Epithelial Cells, Ethylene Oxide, Gas Chromatography, Human
The software applies state of the image processing methods to automatically locate and score comets to characterize and quantify the degree of DNA damage revealed by the comet assay. It is compatible with 4X images which allows for rapid screening of up to 300 comets in seconds when analyzing CometChip®. Trevigens Comet Analysis Software can rapidly evaluate large numbers of cells, related to each treatment group or screening target in a study, and generate summary statistics based on the corresponding numeric results.. ...
Molecular oxygen is two oxygen atoms joined together, and on Earth it is essential for life, where it is produced by photosynthesis. It has been previously detected around some of the icy moons of Jupiter, but it was not expected to be found around a comet. The Rosetta science team originally reported that the oxygen was most likely from the comets main body, or nucleus. This meant it was primordial - that it was already present when the comet itself formed at the beginning of the Solar System 4.6 billion years ago. One group of outside researchers however suggested there might be a different source for molecular oxygen at comets. They had discovered a new way to produce molecular oxygen in space triggered by energetic ions-electrically charged molecules. They proposed that reactions with energetic ions on the surface of comet 67P could instead be the source of the detected molecular oxygen. Now, members of the Rosetta team have analysed the data on 67Ps oxygen in light of the new theory. In ...
The SWAN data captured another surprise. On Sept. 30, the hydrogen jumped by a factor of two and a half in a single day. It dropped down again some six weeks later.. Standard models of how comets behave helped Combis team correlate the hydrogen signature to just how much of the comets surface should be giving off water, a process known as "sublimating," because the water turns directly from ice to a vapor without passing through a liquid phase. The amount of surface area predicted didnt jibe with what EPOXI itself saw - a comet that only gave off water from one half of its shape. But EPOXI also captured images of an extended halo of icy fragments that burst off the comet, most likely flung into space by carbon dioxide emissions on the comets surface. These ice chunks probably added sublimated water to the hydrogen cloud.. "The rate of water generation being so much higher in 1997 implies that the ice fragmentation was even more severe then," says solar physicist Joe Gurman, U.S. project ...
We present a sensitive 3 sigma upper limit of 1.1% for the HNC/HCN abundance ratio in comet 73P/SchwassmannWachmann (fragment B), obtained on 2006 May 10-11, using Caltech Submillimeter Observatory (CSO). This limit is a factor of ~7 lower than the values measured previously in moderately active comets at 1 AU from the Sun. Comet 73P/Schwassmann-Wachmann was depleted in most volatile species, except of HCN. The low HNC/HCN ratio thus argues against HNC production from polymers produced from HCN. However, thermal degradation of macromolecules, or polymers, produced from ammonia and carbon compounds, such as acetylene, methane, or ethane appears a plausible explanation for the observed variations of the HNC/HCN ratio in moderately active comets, including the very low ratio in comet 73P/Schwassmann-Wachmann reported here. Similar polymers have been invoked previously to explain anomalous N-14/N-15 ratios measured in cometary CN. ...
7. The scientific papers and popularized book by S. V. M. Clube and W. M. Napier [Nature, 282 (29 November, 1979), P. 45S; Q. JI. Asir. Soc. (1982),23, pp. 45-66; and The Cosmic Serpent (London and New York, 1982)] deserve comment in light of the present paper. Their statement to the astronomical community that Velikovsky was at least close to correct and that comets (and in particular a body named Venus) did play important roles in early civilizations is long overdue. They also recognize the irrational behavior with which scientists confronted Velikovsky, and the overwhelming data pointing towards worldwide catastrophism caused by comets. I maintain, however, that Clube and Napiers findings support the present paper more precisely than their own theory of terrestrial catastrophism. Both papers agree that comets are of interstellar origin, and that the primordial Oort cloud concept does not explain the observed comet flux in the solar system. They support the ice ball comet model, ...
Ever since its formation, the Earth has been bombarded by comets, and scientists think they now have evidence that these cosmic missiles could have carried the building blocks for life along with them when they impacted.. In 2009, NASAs Stardust mission rendezvoused with the comet Wild-2 and returned to Earth with a sample of an amino acid the probe had picked up from comets outgassing. Tests showed it had too much carbon-13 to have come from Earth, but skepticism remains that simple amino acids could have kick-started the development of life on the planet.. To test that hypothesis, a team of scientists at the University of California, Berkeley, and the University of Hawaii, Manoa, built a pseudo-comet in the lab - a snowball of carbon dioxide, ammonia, and various hydrocarbons such as methane, ethane, and propane - then chilled it in an ultra-high-vacuum chamber down to 10 degrees above absolute zero.. The comet was then zapped with high-energy electrons to simulate the cosmic rays it would ...
http://www.godlikeproductions.com/forum1/message3383800/pg1. People are talking about a "large" comet that is supposedly visible to the naked eye and will be passing on NYE. This is supposed to go down while partyers are out in the streets, waiting for the ball to drop. Some website forums are spelling doom for society and talking about elites taking to underground bunkers in anticipation of the comet slamming into Earth.. This all very closely resembles the plot of the classic 80s camp sci-fi classic Night of the Comet. 80s camp films have a lot of social criticisms embedded in them, which are poignant, and often overlooked. In that film, those who follow the crowd (and stand in the streets watching the comet) are turned into a pile of red dust. Only their sneakers and clothes remain. Just like holiday shoppers -even the survivors in the film would mostly rather go fashion shopping than worry about more practical type things. Meanwhile scientists are living in underground bunkers, aiming to ...
Reduction of comet tail artifacts using image restoration algorithms. Microspheres (15.4 μm diameter) were embedded in O.C.T phantom, imaged, and processed. MIPS of a sub volume are shown. The unprocessed image (a) shows the comet tail artifact extending to a depth of ≈100 μm. RL processing (b) removes comet tail artifacts and restores the shape of the bead both in-plane and along Z. Next-image processing (c) reduces the comet tail artifacts but in-plane spread persists. Wiener deconvolution (d) removes comet tail artifacts but the resultant image suffers from high frequency noise and in-plane restoration is not as effective as in RL. Parameters were: voxel size 4x4x5µm3, (RL, 20 iterations, damping factor of 3), and Wiener, NSR = 10−4. Scale bar corresponds to 50 µm ...
Smearing and smiling in GelRed™ or GelGreen™ precast gels most often caused by overloading of DNA. If you see band migration shifts or smearing and smiling, try reducing the amount of DNA loaded. The recommended loading amount for ladders and samples of known concentration is 50-200 ng/lane. For samples of unknown concentration, try loading one half or one third of the usual amount of DNA. This usually solves band migration problems.. Tip #2: Try the post-staining protocol. To avoid any interference the dye may have on DNA migration, we recommend using the post-staining protocol. If your application requires loading more than the recommended amount of DNA, use the post-staining protocol. While we recommend post-staining gels for 30 minutes, you may be able see bands in as little as five minutes, depending on how much DNA is present. Post-staining solutions can be reused. See the GelRed™ Product Information Sheet or GelGreen™ Product Information Sheet for detailed protocols.. Other tips ...
The comet assay is a sensitive, well established technique for quantifying DNA damage in eukaryotic cells. Compatible with the detection of a wide range of DNA damaging agents, its principle consists in migration of fragmented DNA in an electrophoresis gel (damaged DNA forming the tail of the comet), while intact DNA moves at a slower rate (head of the comet). The percentage of fragmented DNA in the comet tail is a direct measure of DNA damage.. ...
The Hapi region on the neck of Rosettas comet 67P/Churyumov-Gerasimenko reflects red light less effectively than most other regions on the comet. It thus appears slightly blueish. The Hapi region is located between the comets ...
The image shows a beautiful view of Imhotep on the comets large lobe, but with the resolution of NAVCAM at this distance it is not possible to make out the same level of detail as seen in the OSIRIS images depicting changes in the smooth, central portion that were observed in this region before perihelion.. Perhaps the most eye-catching features of the image are the two groups of jets fanning out from the comets top-right horizon. Less defined jets can also be seen all around the sunlit horizon. The silhouette of the comets small lobe is also visible against the background glow of activity towards the bottom left of the image.. The original 1024 x 1024 pixel image is provided below:. ...
Comet Elenin is passing across the STEREO H1B field of view fading as it goes. The comet is actually brighter on the 16th than the 17th, despite what it looks like in the image, as the corona was much brighter on the 16th, and washed out the comet when I increased the brightness. Ive made a little AVI animation of the August 17 images (1 Mb ...
DI-fusion, le Dépôt institutionnel numérique de lULB, est loutil de référencementde la production scientifique de lULB.Linterface de recherche DI-fusion permet de consulter les publications des chercheurs de lULB et les thèses qui y ont été défendues.
Svante Arrhenius väg 8, Stockholm. Arrheniuslaboratoriet, Svante Arrhenius väg 16, Stockholm (Unit for Analytical and Toxicological Chemistry). Mailing address: ...
ORCID: 0000-0001-8562-4944, Williams, J. A., Cole, Kathleen J., Muir, Gordon H., Grover, Philip L. and Phillips, David H. (2000) Susceptibility of primary cultures of human prostate epilthelial cells to chemical carcinogens as detected using the Comet assay. Mutagenesis, 15 (5). p. 447. ISSN 0267-8357 Full text not available from this repository.. Official URL: http://dx.doi.org/10.1093/mutage/15.5.431. ...
N. C. KANSIL & SONS - Exporter, Manufacturer, Supplier, Trading Company of Universe ll (Comets & Meteors) Chart based in New Delhi, India
How big is comet Elenin, then. Lots of people are claiming it is "big" for example "..when i look at the size of the orbit that this thing is huge, heavy…". Well, orbital radius has nothing to do with the size of a comet, lots of long period comets are quite small. In the case of Elenin, its around 3-4 km in size, a bit smaller than Halley (6x 16 Km). We have a reasonable idea of its size from its brightness. Roughly speaking, at a given distance from the sun, the bigger an object is, the brighter its is. Of course, this also depends on how dark it is as well. Comets mess things up a bit as they are brighter than you expect from their size alone, as they are surrounded by a coma of gas and dust reflecting the light of the Sun. Now, comet Elenin is currently roughly magnitude 14, if it were the size of say, the asteroid Vesta, with a diameter of 530 Km, it would be at least magnitude 7 at its current distance. So Elenin has to be fairly small ...
Comet MP30 Diaphragm Pump Repair Kit. We have your pumps, parts & repair kits in stock. We also carry all your other power sprayer components: reels, hose, spray guns, filters, fittings, valves, etc. Order now!
Kato died first. He had been tending the construction mechs - robots that were deploying girders on the thick black dust that overlay the comet ice. From Carls viewpoint, on a rise a kilometer away, Katos suit was a blob of orange amid the hulking gray worker drones. There was no sound, in spite of the clouds of dust and gas that puffed outward near man and machines. Only a little static interfered with a Vivaldi that helped Carl concentrate on his work.
The European Space Agency releases a shape model of Comet 67P/Churyumov-Gerasimenko, which, among other things, allows enthusiasts to print their own 3D version of the ice mountain.
I guess everybody wants to hear about how I almost got killed by a possibly supernatural being. This happened about a month ago, and I blame Comet Hyakutake.
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World-leading developers of image analysis and data processing solutions for the comet assay, Ames test, automatic colony counting and many other areas of scientific research and i
Before purchasing ZEISS COMET, Unika had to send the parts to an external service provider for inspection. Thanks to its optical measuring principle, the ZEISS COMET system perfectly complements the tactile measurements of the ZEISS CONTURA.
i really like your selections. i agree that more content would be appreciated. either way, thanks a lot for sharing these, and for visiting us over at ICOOYS. ...
Related, do you guys think theyll pull those Comet I cars out of storage and use them with an ACS-64? We have a good amount of Comet IIs and IIIs but definitely not enough for 13 engines. We have something like 40-50 of them, not counting the Is, right ...
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Plaques are about one millimeter in diameter. Every plaque is clear, no turbidity. Plaques towards the outside of the plate formed small comet tails towards the outside of the plate. The plaques on the inside were circular with fuzzy edges ...
Calls down a series of 7 icy comets on and around the target, each of which deals 9,136 Frost damage to all enemies within 6 yds of its impact ...
Calls down a series of 7 icy comets on and around the target, each of which deals 9,136 Frost damage to all enemies within 6 yds of its impact ...
... _[PDF]Screening Efficiency (CoMeT) 1 What does cabelcon dk technic terms screening efficiencyenglish pdfWhat does Screening Efficiency mean? Screening efficiency means the ability of the outer
The Australian avionics systems engineer who helped build the Rosetta space craft that successfully landed a probe on a comet will give a free public lecture at the University of Waikato this week.
So this is the problem: A comet is in an elliptical orbit around our Sun. At its point of closest approach, it is moving at 6.3x10^4 m/s and is 4.2x10^10m away from the sun. When it is at the farthest distance, 7.5x10^12m away, how fast is it going? This is what I did K1+U1=K2... Math ...
Petrol attendants are exposed to petrol volatile organic compounds (VOCs) which may have genotoxic and carcinogenic effects. The single-cell gel electrophoresis assay (comet assay) is a method highly sensitive to DNA damage induced by environmental and occupational exposure to carcinogenic and mutagenic agents. The aim of this study was to evaluate the level of exposure of petrol attendants to petrol VOCs and also to determine their effect on DNA damage and repair in lymphocytes of African petrol attendants. The exposed group consisted of 20 subjects, randomly selected from three petrol stations. A control group of 20 unexposed subjects was also chosen and matched for age and smoking habits with the exposed group. Sorbent tubes were used to assess personal exposure of petrol attendants. The comet assay was used to investigate the basal DNA damage and repair capacity in isolated lymphocytes of petrol attendants and unexposed subjects. Blood samples were taken from the petrol attendants at the end ...
Background: The neutral comet assay was devised to measure double-stranded DNA breaks, but it has also been used to measure apoptosis based on its characteristic DNA fragmentation patterns. There is still uncertainty about the reliability of this method. By comparing the comet assay with a flow cytometry method that uses Annexin V binding to apoptotic cells, we have provided further evidence for evaluating the usefulness of the comet assay for detecting apoptosis. Methods: Apoptosis was induced in human peripheral blood mononuclear cells (PBMC) by ionizing radiation and measured using the comet assay and a flow cytometry method that measures Annexin V and propidium iodide (PI) staining. Results: The Annexin V flow cytometry assay distinguished among early apoptosis, late apoptosis, and an apoptotic or necrotic phase in which the cells were labeled with both Annexin V and PI. The comet assay detected only the latter two phases of apoptosis. Conclusions: The comet assay is a useful tool for ...
In order to understand what are comets made of, we need to break down the three main parts of the comet: the nucleus, coma, and tail. Comet nuclei are known to range from about 100 meters to more than 40 kilometers across. They are composed of rock, dust, ice and frozen gases such as carbon monoxide, carbon dioxide, methane, and ammonia. Sometimes called dirty snowballs, recent studies have shown that the ice of a comet is covered by a crust. Comets also contain a variety of organic compounds as well as the gases already mentioned. Some of these are methanol, hydrogen cyanide, formaldehyde, ethanol, and ethane. More complex molecules such as long-chain hydrocarbons and amino acids may also be in comets. Because of their low mass, comets cannot become spherical under their own gravity, and will thus have irregular shapes. The coma is the the nebulous envelope around the nucleus of a comet. It is formed when the comet passes close to the Sun on a highly elliptical orbit. As the comet warms, parts ...
Abstract: Genotoxic Effect of Endosulfan at Sublethal Concentrations in Mori (Cirrhinus mrigala) Fish Using Single Cell Gel Electrophoresis (Comet) Assay
But on December 2, 2011, the discovery of a new Kreutz-family comet was announced. This comet was found the old-fashioned way: from the ground. Australian astronomer Terry Lovejoy spotted the comet, making this the first time a Kreutz comet has been found through a ground-based telescope since the 1970s. The comet has been designated C/2011 W3 (Lovejoy).. Discovering a comet before it moves into view of space-based telescopes, gives scientists the opportunity to prepare the telescopes for the best possible observations. Indeed, since comet Lovejoy was visible from the ground, scientists have high hopes that this might be an exceptionally bright comet, making it all the easier to view and study. (Some Kreutz comets -- such as Ikeya-Seki in 1965 -- are so bright they can be seen with the naked eye in the daytime, though this is extremely rare.). ...
Pic Alcohol is pretty essential to life here on Earth, but for the first time, scientists have found the blessed fluid venting in huge amounts from a comet flying through our Solar System.. Comet Lovejoy swung around our sun for the first time in 8,000 years back in January. Astronomers kept a close eye on it because the sunlight caused chemicals in the offgassing comet to glow at specific microwave frequencies, and the results were quite a shocker.. "We found that comet Lovejoy was releasing as much alcohol as in at least 500 bottles of wine every second during its peak activity," said Nicolas Biver of the Paris Observatory, France, lead author of a paper on the discovery published October 23 in Science Advances.. Lovejoy was shown to be shedding ethyl alcohol, but the team also spotted glycolaldehyde, a simple sugar, in the comets tail. Sadly, for those keen on trying a proper Pan Galactic Gargle Blaster, the bulk of the comet is water, but there are still serious amounts of booze and sugar ...
Previous in vivo studies showed the combination pentoxifylline (PTX) and a-tocopherol was highly efficient in reducing late radiation-induced skin damage. The present work aimed at investigating the molecular and cellular mechanisms involved in the effects of this combination. Primary cultures of confluent dermal fibroblasts were ?-irradiated in the presence of PTX and trolox (Tx), the water-soluble analogue of a-tocopherol. Drugs were added either before or after radiation exposure and were maintained over time. Their antioxidant capacity and their effect on radiation-induced ROS production was assessed together with cell viability and clonogenicity. DNA damage formation was assessed by the alkaline comet assay and by the micronucleus (MN) test. Cell cycle distribution was also determined. The combination of PTX/ Tx was shown to reduce both immediate and late ROS formation observed in cells after irradiation. Surprisingly, decrease in DNA strand breaks measured by the comet assay was observed ...
The European Space Agencys Rosetta probe travelled all the way to comet 67P/Churyumov-Gerasimenko to collect unprecedented cometary details. The space probe keeps sending unexpected particulars about the comet-particulars with implications far beyond the comet itself.. As Rosetta approached the comet in the fall of 2014, its instruments began detecting chemicals in space nearby the comet. The missions earliest discoveries included an unexpected fountain-like emission of over 6,000 gallons of water vapor per day.1 Similar to the plumes that eject material into space from Saturns moon Enceladus, this surprising level of activity points to a much younger comet than commonly asserted.. In December 2014, Rosettas researchers published more particulars. This time they revealed that the comets water has a deuterium-to-hydrogen ratio about three times higher than Earths water.2 Deuterium is similar to ordinary hydrogen but has a heavier, yet stable, nucleus. In the nature-only, billions-of-years ...
Comet C/2013 A1 Siding Spring will make a close flyby of Mars on Oct. 19, 2014. At a distance of only 87,000 miles - about 1/3 the distance between the Earth and moon - its a near miss of the Red Planet. Find out how NASAs Mars orbiters will evade dust from the comet. Transcript:. (Music). Don Yeomans:. This is going to be an opportunity to observe a brand new comet and we noted immediately that its going to make a very close approach to Mars on Oct. 19th.. Zurek:. When we first heard about the comet and that it was coming very close to Mars, we had so little tracking information that there was a possibility it could hit Mars.. Lock:. The accuracy of the trajectory started to improve and we realized it wasnt going to hit Mars but still might provide a threat to our spacecraft there.. (Music). Zurek:. This is a first time visitor from the outer solar system, from the Ort Cloud. Thats coming in close to where we can see it and close enough that its actually encountering Mars.. Lock:. Comets ...
What happens after Rosetta arrives at comet 67P/Churyumov-Gerasimenko? This animation describes the key dates for the next set of manoeuvres that will bring Rosetta even closer to the comet between August and October. After arriving on 6 August, Rosetta will follow a set of two, three-legged triangular trajectories that require a small thruster burn at each apex. The legs are about 100 km long and it will take Rosetta between three and four days to complete each one. The first triangle is conducted at a distance of about 100 km from the comet, the second at around 50 km. Then Rosetta will switch to a global mapping phase at an altitude of about 30 km. During this period, it will make a night excursion, whereby the ground track of the spacecraft will be on the night-side of the comet (with the spacecraft still fully illuminated the Sun). In October Rosetta will transfer to a close mapping phase to observe the comet from a distance of 10 km. The spacecraft will move even closer to dispatch ...
Within two years, my band The Foghorns had made our big debut in Seattle, then played almost monthly gigs, almost exclusively at the Comet. We developed our new sounds, wrote songs about life around booze with the ultimate critics-the locals- judging us extremely vocally. I remember having a stiff show, and hearing, at the beginning of three songs "Hey waiter!!" Positive quotes are slightly less memorable. Youd get the weird quiet, or youd get people singing along . . . even on new songs. (A key point: Ive played more than two dozen gigs at the Comet in various bands, and Ive never seen an ACTUAL CRITIC, that is, someone who writes about music for publication, at the Comet. Another key point: Ive been fortunate enough to be featured as a pick in publications- but NEVER for a Comet show.). For The Foghorns, we got our degrees from The Comet, playing constantly, moving from early weekday gigs to Thursdays to, finally, weekends. The experiences-nothing ever quite going right, but every gig ...
Increased level of DNA damage, but not FPG sensitive sites, in lung cells by the alkaline comet assay in guinea pigs after intratracheal instillation of diesel engine exhaust particles. / Pedersen, L.M.; Møller, Per; Danesvar, B.; Wallin, H.; Autrup, H.; Loft, S.; Dragsted, L.O.. In: Neoplasma, Vol. 46, No. Suppl. S, 1999, p. 85-85.. Publication: Research - peer-review › Conference abstract in journal - Annual report year: 1999 ...
Sigma-Aldrich offers abstracts and full-text articles by [Atul Katarkar, Sanjit Mukherjee, Masood H Khan, Jay G Ray, Keya Chaudhuri].
By Dr. Manish Sinha. Since time immemorial, scientists have been perplexed by an array of questions about the Earths past and the European Space Agencys Rosetta mission, launched on 2 March, 2004 attempted to elucidate one of our planets most ancient mysteries: just how was Earth seeded with water? Whilst Earth-based instruments have successfully decoded cosmic fingerprints emanating from the early solar system, certain information requires physical samples that can be obtained from interplanetary missions alone. Rosetta represents the nineteenth mission to explore comets and a paradigm shift from prior endeavours in terms of technological advancement and sheer audacity of its undertaking. Preceding missions amounted to mere fly-bys. Rosetta, by contrast, is the inaugural mission designed to orbit around and landing upon a comet blazing a trail at speeds of 85,000 mph as well as conduct the first in situ tests of material extracted directly from the comet surface. Additionally, it will travel ...
Gentronix is pleased to announce the introduction of its new early genotoxicity screening assay BlueScreen HC. BlueScreen HC is a human cell-based reporter assay that monitors expression of the GADD45a gene, a P53 target that is up-regulated in response to all types of genotoxic stress. To coincide with the expansion of cell-based screening services, Gentronix has also announced the introduction of its in vitro Comet assay service.
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Comet collisions on planets and moons could create the building blocks of life, scientists say. Comets are known to possess organic compounds.
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A European spacecraft orbiting a distant comet has finally answered a question we've all been wondering: What does a comet smell like? "It stinks
Proper Care of Comet Goldfish. Of the more than twenty varieties of goldfish that exist, Comet goldfish are one of the most common types. They look very similar
this video from NASA gives an idea of just how close to the sun comet ISON will pass! all comets have such elongated orbits, where they zoom in very close to the sun and then shoot way out to the farthest reaches of the solar system ...
Generation of Plp-null embryonic stem cells,neo, and rec mice. Three homologous recombinant embryonic stem cell (ES) clones were obtained from a Southern blot screen of 300 G418-resistant colonies. Chimeric male mice derived from clone 17 or clone 34 transmitted the Plp-nullallele (neo allele) through the germline, and the knock-out mice generated were phenotypically indistinguishable. Subsequent characterization and genetic manipulations were performed on mice derived from ES cell clone 34. Southern blots of tail DNA digested withPstI and electrophoresed on 0.8% agarose gels yielded 8.5 kb (wild-type allele) or 4.3 kb (knock-out allele) bands when hybridized with a 1.2 kb PstI-EcoRI fragment of intron 1 flanking the 5′ end of the targeting construct (Fig. 1). The presence of the PGKneo cassette was revealed as a 1.8 kb band using a 0.6kb PstI neomycin coding region to probe Southern blots of HindIII/XhoI-digested tail DNA. To generate rec (DM-20 only) mice, male neo(DM-20/PLP absent) mice ...
Abstract: We propose to determine if and how the rotation state of Comet 2P/Encke changes from orbit to orbit. Time series of photometry in 2005, while the comet is near aphelion, will indicate if the dominant periodicity has changed from that measured around the previous aphelion, in 2001-2002. While it is possible that the comet is in non-principal axis rotation, one phenomenon that could also be present in the data is a secular drift of the rotation period caused by outgassing torques. The comets emission of gas can provide a reaction force that could be spinning up the nucleus. Such a phenomenon must be taken into account if we are to understand P/Enckes rotation state. Furthermore this could be used to derive the comets mass and density, fundamental properties that are poorly constrained among cometary nuclei. Comparison of data from the 1980s and the early 2000s suggests that the dominant periodicity is decreasing by about 2.4 minutes per orbit, but we need much more detailed coverage ...
http://star.arm.ac.uk/preprints/2009/539.pdf. We know that about one bright comet (of absolute magnitude as bright as 7, comparable to Halleys Comet) arrives in the visibility zone (perihelion q,5AU, say) each year from the Oort cloud. It seems to be securely established that ~1-2% of these are captured into Halleytype (HT) orbits. The dynamical lifetime of a body in such an orbit can be estimated, from which the expected number of HT comets is perhaps ~3000. The actual number of active HT comets is ~25. This discrepancy of at least two powers of 10 in the expected impact rate from comets as deduced from this theoretical argument on the one hand, and observations on the other, is …. Read the full story » ...
Download assay protocols for a look at how to perform an assay on Celigo, or demonstration experiments for a detailed look at how we performed the assay with a customer
A Caltech chemical engineer who normally develops new ways to fabricate microprocessors in computers has figured out how to explain a nagging mystery in space -- why comets expel oxygen gas, the same gas we humans breathe.
It was clear and frosty. Over the dirty, half-dark streets, over the black roofs was a dark, starlit sky. It was only looking at the sky that Pierre forgot the mortifying meanness of all things earthly in comparison with the height his soul had risen to. As he drove into Arbatsky Square, the immense expanse of dark, starlit sky lay open before Pierres eyes. Almost in the centre of it above the Prechistensky Boulevard, surrounded on all sides by stars, but distinguished from all by its nearness to the earth, its white light and long, upturned tail, shone the huge, brilliant comet of 1812; the comet which betokened, it was said, all manner of horrors and the end of the world. But in Pierres heart that bright comet, with its long, luminous tail, aroused no feeling of dread. On the contrary, his eyes wet with tears, Pierre looked joyously at this bright comet, which seemed as though after flying with inconceivable swiftness through infinite space in a parabola, it had suddenly, like an arrow ...
Space probe confirms chemicals of life in comets halo - AP News: BERLIN (AP) - Scientists have found further evidence supporting the .12/14/2017 18:27:27PM EST.
The COMET Initiative brings together researchers interested in the development and application of agreed standardised sets of outcomes, known as a core outcome set.
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A comet strike may have triggered the rapid warming of Earth caused by an accumulation of atmospheric carbon dioxide 56 million years ago
DAY LEWIS, Cecil. Country Comets, London: Martin Hopkinson, 1928, 8°, FIRST EDITION, original green boards (spine faded); The Magnetic Mountain, London: Hogarth Press, 1933, 8°, original green pictorial boards (spine faded) [Woolmer 318b]; Noah and the Waters, London: Hogarth Press, 1936, 8°, FIRST EDITION, original yellow cloth, dust-jacket (a little soiled) [Woolmer 383b]. With 15 other works by the same author. (18) ...
The impact of comets crashing into Earths surface may have provided the energy to create simple molecules that formed the precursors to life, a new study suggests.
One thousand catalogued observations of the star Beta Pictoris over an eight-year period have shown the young system to have two families of comets surrounding it.
The 10-year journey of the Rosetta spacecraft reached a milestone with todays successful touchdown of the Philae lander on comet P67, and scientists will now begin to gather a wealth of information to analyze.
Read {MP3 ZIP} Download May All Be Dead by Cadaver Disposal from the story Comet by prefragrant1976 with 0 reads. child, drink, robot. Simple Way to Listen / D...
The protective effect of extract of Crataegus pinnatifida (Rosaceae) pollen (ECPP) on the DNA damage response to oxidative stress was investigated and assessed with an alkaline single-cell gel electrophoresis (SCGE) assay and pBR322 plasmid DNA breaks in site-specific and non-site-specific systems. Total phenolic content, total flavonoid content, individual phenolic compounds, antioxidant activities (1,1-diphenyl-2-picrylhydrazyl (DPPH), radical scavenging activity, FRAP, and chelating activity) were also determined. The results showed that ECPP possessed a strong ability to protect DNA from being damaged by hydroxyl radicals in both the site-specific system and the non-site-specific system. It also exhibited a cytoprotection effect in mouse lymphocytes against H2O2-induced DNA damage. These protective effects may be related to its high total phenolic content (17.65±0.97mgGAE/g), total flavonoid content (8.04±0.97mgrutin/g), strong free radical scavenging activity and considerable ferrous ion ...
Pollutants including insecticides have been recently reported to be a risk factor involved in various diseases. Permethrin, a member of the family of synthetic pyrethroids, is widely used as insecticide in agriculture and other domestic applications. To investigate possible cardiotoxicity, we had examined different concentrations of permethrin on the freshly isolated rat heart cells using the alkaline comet assay. A significant difference in % tail DNA between all concentrations of permethrin (5, 10, 20 μM) and vehicle (control) without enzymes and with Fpg-treated cells were measured. The results indicated that permethrin induced oxidative damage to purine bases in the heart cells. Pyrimidines oxidation was evaluated using Endonuclease III (Endo III), but the results did not reveal any significant changes. After permethrin exposure, cells were studied to evaluate their DNA repair capacity. A complete DNA repair at 10 and 20 μM was measured after 30 and 60 min of repair intervals. Significant ...
The effects of nicotinamide (NIC) and its natural plant metabolites nicotinic acid (NIA) and trigonelline (TRIG) were studied with respect to defense in plant cell cultures. NIC and NIA could protect against oxidative stress damage caused by 2,2′-azobis(2-amidinopropane) dihydrochloride (AAPH), which generates free radicals. Damage was analyzed as DNA strand breaks in cell cultures of Pisum sativum (garden pea), Daucus carota (carrot), Populus tremula L. × P. tremuloides (hybrid aspen) and Catharanthus roseus (Madagascar periwinkle), monitored by single cell gel electrophoresis (comet assay), and assays of cell leakage in C. roseus. The activities of aconitase and fumarase enzymes, which have key roles in energy metabolism, were analyzed in P. sativum cultures after treatment with NIC or NIA. Aconitase activity was increased by NIA, and fumarase activity was increased by both compounds. These compounds were shown to promote glutathione metabolism in P. sativum cultures, and NIC was shown to ...
JUNQUEIRA, Adriana Pereira Freire; PERAZZO, Fabio Ferreira; SOUZA, Gustavo Henrique Bianco and MAISTRO, Edson Luis. Clastogenicity of Piper cubeba (Piperaceae) seed extract in an in vivo mammalian cell system. Genet. Mol. Biol. [online]. 2007, vol.30, n.3, pp.656-663. ISSN 1415-4757. http://dx.doi.org/10.1590/S1415-47572007000400025.. The plant Piper cubeba is widely distributed in tropical and subtropical regions and is used medically for various purposes but has not yet been evaluated for genotoxicity. We used male and female Swiss mice and Wistar rats and the comet assay and micronucleus test to investigate the mutagenic potential of a crude extract of P. cubeba seeds. The rodents were administered 0.5 g kg-1, 1.0 g kg-1 and 1.5 g kg-1 of the extract by gavage. For the Swiss mice, peripheral blood was collected 24 h after treatment for the comet assay, and at 48 and 72 h for the micronucleus test. For the Wistar rats, peripheral blood and hepatic cells were collected for the comet assay and ...
Ethanolic extract of Casearia sylvestris is thought to be antimutagenic. In this study, we attempted to determine whether this extract and casearin X (a clerodane diterpene from C. sylvestris) are protective against the harmful effects of airborne pollutants from sugarcane burning. To that end, we used the Tradescantia micronucleus test in meiotic pollen cells of Tradescantia pallida, the micronucleus test in mouse bone marrow cells, and the comet assay in mouse blood cells. The mutagenic compound was total suspended particulate (TSP) from air. For the Tradescantia micronucleus test, T. pallida cuttings were treated with the extract at 0.13, 0.25, or 0.50 mg/ml. Subsequently, TSP was added at 0.3 mg/ml, and tetrads from the inflorescences were examined for micronuclei. For the micronucleus test in mouse bone marrow cells and the comet assay in mouse blood cells, Balb/c mice were treated for 15 days with the extract-3.9, 7.5, or 15.0 mg/kg body weight (BW)-or with casearin X-03, 0.25, or 12 mg/kg ...
The objective of this study was to evaluate the sub-lethal toxicity of hexabromocyclododecane (HBCDD) in fish. Adult Chinese rare minnows as in vivo models were exposed to waterborne HBCDD from 1 to 500 mu g/l for 14, 28 and 42 days. Hepatic CYP1A1 (ethoxyresorufin-O-deethylase, EROD) and CYP2B1 (pentaoxyresorufin-O-depentylase, PROD) activities were measured. At the same time, molecular biomarkers of oxidative stress were also assayed in the brain, including reactive oxygen species (ROS), lipid peroxidation products (thiobarbituric acid-reactive substances, TBARS), DNA damage and protein carbonyl, as well as superoxide dismutase (SOD) activity and glutathione (GSH) content. DNA damage was evaluated using the Comet assay on erythrocytes. Besides, the content of HBCDD in whole fish was determined after 42 days exposure. The results show that HBCDD could induce EROD and PROD at 500 mu g/l after 28 days exposure, and at 100 to 500 mu g/l after 42 days exposure (P < 0.05), respectively. ROS ...
Last time, I talked about the asteroid that hit the Earth about 65 million years ago, on the Mexican coast of the Gulf of Mexico. It was quite a show.. Amazingly, we have seen something very similar happen to Jupiter, the biggest planet in the solar system.. Back in 1992, a big comet (later called Shoemaker-Shoemaker-Levy-1993e) was zipping around inside the solar system.. As this comet swung past the planet Jupiter, it got broken into 21 smaller comets, because it had come too close. The biggest of these comets was about two kilometres across.. Between 16-22 July 1994, the 21 lumps smashed into Jupiter, impacting at about 60 kilometres per second.. Most of these comet fragments had about 100-times less energy than the asteroid that killed the non-avian dinosaurs on our planet, about 65 million years ago.. Even so, they threw up huge fountains of glowing-hot debris, hotter than the surface of the sun.. And as the debris landed, it covered areas on the gas surface of Jupiter much bigger than our ...
Air pollution, containing high-level of ultrafine particles (UFP) and benzene, is a prominent environmental health problem in many cities of the World. We investigated the level of oxidative DNA damage in mononuclear blood cells (MNBC) by the comet assay as DNA strand breaks (SB) and formamidopyrimidine DNA glycosylase (FPG) sensitive sites in residents from three urban locations in Cotonou, Benin (taxi-moto drivers, subjects living near roads with intense traffic and suburban residents) and rural residents. Exposure was characterized by urinary excretion of S-phenylmercapturic acid (S-PMA), a biomarker of benzene exposure, and by ambient UFP. There were clear stepwise gradients with respect to ambient UFP, S-PMA excretion and oxidative DNA damage with rural subjects , suburban subjects , residents living near highly trafficed roads,taxi-moto drivers. Polymorphisms in glutathione peroxidase (GPX), NAD(P)H:quinone oxidoreductase 1 (NQO1) and glutathione S-transferase (GST) genes were assessed for ...
Comet assayEdit. See also: Comet assay. Comet assays are one of the most common tests for genotoxicity. The technique involves ... As a consequence, many sophisticated techniques including Ames Assay, in vitro and in vivo Toxicology Tests, and Comet Assay ... Bacterial Reverse Mutation AssayEdit. See also: Ames test. The Bacterial Reverse Mutation Assay, also known as the Ames Assay, ... To assay for genotoxic molecules, researchers assay for DNA damage in cells exposed to the toxic substrates. This DNA damage ...
Møller, P (2005). "Genotoxicity of environmental agents assessed by the alkaline comet assay". Basic Clin Pharmacol Toxicol. 96 ...
February 2006). "A comet assay study reveals that aluminium induces DNA damage and inhibits the repair of radiation-induced ... Yiu G (December 2004). "Rapid Communications: Antiperspirant Induced DNA Damage in Canine Cells by Comet Assay". Toxicol. Mech ...
"Comparative investigation of multiple organs of mice and rats in the comet assay". Mutat. Res. 517 (1-2): 53-75. doi:10.1016/ ...
Koppen, G.; Verschaeve, L. (2001). "The alkaline single-cell gel electrophoresis/comet assay: a way to study DNA repair in ...
Simon L, Lutton D, McManus J, Lewis SE (2011). "Sperm DNA damage measured by the alkaline Comet assay as an independent ...
As a consequence, many sophisticated techniques including Ames Assay, in vitro and in vivo Toxicology Tests, and Comet Assay ... Comet assays are one of the most common tests for genotoxicity. The technique involves lysing cells using detergents and salts ... Tice, R.R. (2000). "Single Cell Gel/Comet Assay: Guidelines for In Vitro and In Vivo Genetic Toxicology Testing" (PDF). ... To assay for genotoxic molecules, researchers assay for DNA damage in cells exposed to the toxic substrates. This DNA damage ...
It can be measured by e.g. the Comet assay or by the TUNEL assay. Men with sperm motility defects often have high levels of ... Using bright-field microscopy, the SCD test appears to be more sensitive than the TUNEL assay. Its main units of measurement is ... comparison between sperm chromatin dispersion test and terminal uridine nick-end labeling assay". Fertil. Steril. 94 (3): 1027- ... and TUNEL assay are both effective in detecting sperm DNA damage. ...
The comet assay in eight mouse organs: results with 24 azo compounds. Mutation Research/Genetic Toxicology and Environmental ... Repeated-dose liver and gastrointestinal tract micronucleus assays with CI Solvent Yellow 14 (Sudan I) using young adult rats. ... Repeated-dose liver and gastrointestinal tract micronucleus assays with CI Solvent Yellow 14 (Sudan I) using young adult rats. ...
"DNA Damage Measured by the Comet Assay in Head and Neck Cancer Patients Treated with Tirapazamine1". Neoplasia.com. Retrieved ...
Electrophoretic preparations used in the case of comet assay can benefit from the use of water objectives. The refractive index ...
A Pilot Study with Alkaline Comet Assay". Archives of Industrial Hygiene and Toxicology. 62. doi:10.2478/10004-1254-62-2011- ...
Comet) assay". Env. Mol. Mut. 29 (3): 277-288. doi:10.1002/(SICI)1098-2280(1997)29:3. 3.0.CO;2-9. CS1 maint: Multiple names: ...
Determination of the effects of some artificial sweeteners on human peripheral lymphocytes using the comet assay. Journal of ...
The damage to the DNA was measured for individual cells using single-gel electrophoresis via the comet assay. Researchers have ...
Swain, U; Subba Rao, K (Aug 2011). "Study of DNA damage via the comet assay and base excision repair activities in rat brain ... link) Hashimoto, K; Takasaki, W; Sato, I; Tsuda, S (Aug 2007). "DNA damage measured by comet assay and 8-OH-dG formation ... January 1998). "DNA oxidation matters: the HPLC-electrochemical detection assay of 8-oxo-deoxyguanosine and 8-oxo-guanine". ... "Gene-specific oxidative lesions in aged rat brain detected by polymerase chain reaction inhibition assay". Free Radic Res. 41 ( ...
... in human cells evaluated with the comet assay". Mutat. Res. 629 (1): 7-13. doi:10.1016/j.mrgentox.2006.12.007. PMID 17317274. ...
... in human cells evaluated with the comet assay". Mutat. Res. 629 (1): 7-13. doi:10.1016/j.mrgentox.2006.12.007. PMID 17317274.. ... Cellulose acetate is degraded within 2-3 weeks under aerobic assay systems of in vitro enrichment cultivation techniques and an ... assays of Phillip Morris, Inc Date Milestones and documents. ...
February 2006). "A comet assay study reveals that aluminum induces DNA damage and inhibits the repair of radiation-induced ...
N. P. Singh of the "comet" assay for single cell DNA damage[3]. Schneider is the chairperson of the Advisory Committee to the ...
However, when human cell lines were tested and a Comet assay was conducted, BPF caused DNA fragmentation when introduced to the ... Audebert, Marc; Dolo, L.; Perdu, E.; Cravedi, J.-P.; Zalko, D. (2011-06-09). "Use of the γH2AX assay for assessing the ...
"Analysis of genotoxic potentiality of stevioside by comet assay". Food Chem Toxicol. 45 (4): 662-6. doi:10.1016/j.fct.2006.10. ... 1996). "Evaluation of the genotoxicity of stevioside and steviol using six in vitro and one in vivo mutagenicity assays". ...
The single cell gel electrophoresis assay (SCGE, also known as comet assay) is an uncomplicated and sensitive technique for the ... The comet assay is an extremely sensitive DNA damage assay. This sensitivity needs to be handled carefully as it is also ... The overall structure resembles a comet (hence "comet assay") with a circular head corresponding to the undamaged DNA that ... Comet) assay. I. Management of invasive transitional cell human bladder carcinoma. II. Fluorescent in situ hybridization Comets ...
... by comet assay, advanced maternal age and semen quality. A systematic meta-analysis of 24 estimates of DNA damage based on a ...
Level of DNA fragmentation[19] as measured e.g. by Comet assay, advanced maternal age and semen quality. ...
Comet plot : A two- or three-dimensional animated plot in which the data points are traced on the screen. Contour plot : A two- ... chemistry and biostatistics this plot is a method of data plotting used in analysing the agreement between two different assays ... Phase path of Duffing oscillator plotted as a comet plot Animated marker over a 2D plot Contour plot Funnel plot : This is a ...
... by comet assay, advanced maternal age and semen quality. A systematic meta-analysis of 24 estimates of DNA damage based on a ...
... art of assaying Dosiology - study of doses Dramaturgy - art of producing and staging dramatic works Dysgenics - study of racial ... study of comets Conchology - study of shells Coprology - study of pornography Cosmetology - study of cosmetics Cosmology - ...
The single cell gel electrophoresis assay (SCGE, also known as comet assay) is an uncomplicated and sensitive technique for the ... The comet assay is an extremely sensitive DNA damage assay. This sensitivity needs to be handled carefully as it is also ... The overall structure resembles a comet (hence "comet assay") with a circular head corresponding to the undamaged DNA that ... Comet) assay. I. Management of invasive transitional cell human bladder carcinoma. II. Fluorescent in situ hybridization Comets ...
... also called alkaline Comet Assay is a method measuring DNA strand breaks in eukaryotic cells.Each treated group is composed of ... Based on their size DNA fragments migrate away from the head to the tail, and the intensity of the comet tail relative to the ... This results in structures resembling comets which by using suitable fluorescent stain, can be observed by fluorescent ... The in vivo alkaline single cell gel electrophoresis assay, ... 489: In Vivo Mammalian Alkaline Comet Assay. In series:OECD ...
The PrimeFlow® RNA assay is a unique in situ hybridization assay that combines the power of branched-DNA technology with the ... Join us in a discussion about leveraging the PrimeFlow® RNA assay to answer unique research questions including:. *Delineating ... Essentially, the PrimeFlow® RNA assay combines the analysis of gene and protein expression in a single application. ...
The Comet Assay in Toxicology is the first book of its kind to be devoted exclusively to the Comet assay and its applications ... the Comet assay - in the field of modern toxicology. The assay is a simple, sensitive rapid and visual technique for the ... This is a unique reference book as it provides the scientific community with the advances in Comet assay as well as its ... This section sets the scene by explaining why the assay has become the most sensitive and sought after assay in modern ...
The Comet Assay, also called single cell gel electrophoresis (SCGE), is a sensitive and rapid technique for quantifying and ... The Comet Assay Interest Group website includes references and protocols for the Comet Assay and maintains a list of companies ... Review Articles and General References for Comet Assays. *Anderson D., et al., Comet assay responses as indicators of ... McKelvey-Martin, V.J., et al., The single cell gel electrophoresis assay (comet assay): A European review. (Review) Mutat. Res ...
The comet assay (single-cell gel electrophoresis) is a simple method for measuring deoxyribonucleic acid (DNA) strand breaks in ... Comet) assay. I. Management of invasive transitional cell human bladder carcinoma. II. Fluorescent in situ hybridization Comets ... 2003) Recommendations for conducting the in vivo alkaline comet assay. Mutagenesis 18, 45-51.PubMedCrossRefGoogle Scholar ... 1997) Comet assay in human biomonitoring studies: reliability, validation, and applications. Env. Mol. Mutagen. 30, 139-146. ...
Andors Komet software used to automatically score modified 3D Comet assay results. *Download PDF Copy ... According to Professor Anderson, The comet assay is a standard method for assessing DNA genomic damage, relying on the ... Andor Technology Ltd.. Andors Komet software used to automatically score modified 3D Comet assay results. News-Medical. 27 ... Andors Komet software used to automatically score modified 3D Comet assay results. News-Medical, viewed 27 May 2020, https ...
Comet Assay - Free download as Powerpoint Presentation (.ppt), PDF File (.pdf), Text File (.txt) or view presentation slides ... Comet assay. The Comet Assay, also called single cell gel electrophoresis (SCGE), is a sensitive and rapid technique for ... The extent of DNA liberated from the head of the comet is directly proportional to the amount of DNA damage. The Comet Assay ... as the Alkaline Comet Assay. The resulting image that is obtained resembles a comet with a distinct head and tail. The head ...
The comet assay is an efficient method to detect DNA damage including single and double-stranded DNA breaks. We describe ... Alkaline comet assay data plot. **p ,0.01. (B) Neutral comet assay data plot. **p ,0.01. (C) Comet assay analysis revealed the ... The toolbar of the comet assay software. (B) Alkaline comet assay as an example: the user interface of comet assay software ... Proceed to alkaline (step 3.2) or neutral (step 3.3) comet assay. *For alkaline comet assay *Gently remove slides from the LS, ...
Sperm Comet Assay (SCGE). * For permission to use this image or to obtain a higher quality please contact:. Dr.Philip Chan. ...
4.1%, P,0.001). BD exposure had no significant effects on formation of micronuclei and on comet assay parameters. Effect of ... Chromosomal aberrations, sister-chromatid exchanges, cells with high frequency of SCE, micronuclei and comet assay parameters ... comet assay parameters like tail length (TL) and percentage of DNA in tail [T (%)] and polymorphisms of GSTM1 and GSTT1 ...
The alkaline single cell gel electrophoresis assay (known as the comet assay) in individual cells was adapted for detecting ... DNA damage detected by the comet assay in the white blood cells of workers in a wooden furniture plant.. Palus J1, ... The level of DNA damage was determined as the percentage of cells with comets. It was assessed in cells before and after ...
Comet Assay / Standard Comet Assay (CometAssay®) / CometAssay® Reagent Kits / CometAssay® Kit (96 well, 1 slide). ... "Differences in quantification of DNA double-strand breaks assessed by 53BP1/ H2AX focus formation assays and the comet assay in ... CometAssay® Kit (96 well, 1 slide). $247.00. CometAssay® 96 Kit includes one specially treated CometSlide™ (96 Well) and ... CometAssay® Kit (96 well, 1 slide) quantity. Add to cart. Available Size(s): 96 Samples Catalog Number: 4253-096-K Category: ...
Comet assay, and preliminary trandescantia mic... by ggorjan in Types > School Work, Genotoxicity, and sciencebiology ... According to these results we can assume that the comet assay was the most sensitive assay, followed by the micronucleus test. ... Genotoxicity evaluation of water soil leachates by Ames test, comet assay, and preliminary Tradescantia micronucleus assay B. ... Genotoxicity evaluation of water soil leachates by Ames test, Comet assay, and preliminary trandescantia micronucleus assay. ...
Comet Assay / Standard Comet Assay (CometAssay®) / CometAssay® Reagent Kits / CometAssay® Kit (25 x 2 well slides). ... Differences in quantification of DNA double-strand breaks assessed by 53BP1/ H2AX focus formation assays and the comet assay in ... CometAssay® Kit (25 x 2 well slides). $247.00. CometAssay® Kit includes twenty-five specially treated CometSlides™ (2 Well) and ... CometAssay® Kit (25 x 2 well slides) quantity. Add to cart. Available Size(s): 50 samples Catalog Number: 4250-050-K Category: ...
Single cell gel electrophoresis or the comet assay is a sensitive technique to quantify different types of DNA damage, e.g... ... Article Effects of proton beams from the folded tandem ion accelerator on DNA damage in mouse leukocytes using the comet assay ... Daphnia magna acute toxicity assay, comet assay, cytokinesis-block micronucleus and E-screen assay were... ... Effects of proton beams from the folded tandem ion accelerator on DNA damage in mouse leukocytes using the comet assay. 0 ...
The Comet Assay as a Rapid Test in Biomonitoring Occupational Exposure to DNA-damaging Agents and Effect of Confounding Factors ... The Comet Assay as a Rapid Test in Biomonitoring Occupational Exposure to DNA-damaging Agents and Effect of Confounding Factors ... The Comet Assay as a Rapid Test in Biomonitoring Occupational Exposure to DNA-damaging Agents and Effect of Confounding Factors ... The Comet Assay as a Rapid Test in Biomonitoring Occupational Exposure to DNA-damaging Agents and Effect of Confounding Factors ...
For this, MN assay of exfoliated epithelial cells was compared with comet assay of peripheral blood leucocytes among 260 ... Thus, the extent of DNA damage evaluation by the comet assay in peripheral blood cells is perfectly reflected by the MN assay ... This study compares the micronucleus (MN) assay in oral buccal mucosa cells with the comet assay in peripheral blood cells in a ... Comparative evaluation of genotoxicity by micronucleus assay in the buccal mucosa over comet assay in peripheral blood in oral ...
Comet Assay Extension. Fully Automatic Comet Assay Analysis with Optional User Validation and Support of Virtual Slides. The ... Feel free to contact us to get further information about Aphelion Comet Assay Extension.. Link to download Aphelion Comet Assay ... The Comet Assay Extension supports many image formats (e.g., Tiff, Jpeg, Dib and CO1 format) with 8 and 12 bit images. ... Comet Assay is an extension for Aphelion Dev that performs image processing and image analysis on digital images captured with ...
The specificity of the Comet assay was improved by coupling the assay to 8-oxoguanine-glycosylase (hOGG1), which by catalyzing ... Agreement between the comet assay and LC/MS detection of 8-Oxo-2-deoxyguanosine (8-oxo-dGuo) in human lung adenocarcinoma ( ... Agreement between the comet assay and LC/MS detection of 8-Oxo-2-deoxyguanosine (8-oxo-dGuo) in human lung adenocarcinoma ( ... Agreement between the comet assay and LC/MS detection of 8-Oxo-2-deoxyguanosine (8-oxo-dGuo) in human lung adenocarcinoma ( ...
Variability between the CometChip assays are less than 10%, with no overlapping comets requiring manual editing. The well-to- ... The CometAssay Analysis Software has automated comet acquisition and scoring that can analyze more than half a million comets ... Additional CometAssay Resources. Choosing the Right Model System for Hepatotoxicity. DNA Damage and Repair Kits & Reagents. ... Learn more about R&D Systems CometAssay and CometChip. In this webinar, we demonstrate how CometChips versatility can be used ...
In this study, we evaluated DNA integrity using the comet as... ... KEY WORDS: comet assay, genotoxic damage, peripheral blood ... The comet assay could contribute to treatment decisions, especially by taking into account the patients basal DNA damage ... In this study, we evaluated DNA integrity using the comet assay in peripheral blood lymphocytes from breast cancer patients ... These results support the usefulness of the comet assay as a sensitive technique to evaluate basal DNA status and DNA damage ...
Comet assay. DNA single- and double-strand breaks were detected by alkaline and neutral comet assays, respectively, as ... Representative comet assay images showing single-strand breaks in DNA of ECT1/E6 E7 cells treated with vehicle, 0.2% DMSO (a), ... The comet assay. Principles, applications, and limitations. Methods Mol Biol. 2002;203:163-177. [PubMed] ... Cigarette smoke-induced DNA damage and repair detected by the comet assay in HPV-transformed cervical cells. Afsoon Moktar,1 ...
Gentronix has also announced the introduction of its in vitro Comet assay service. ... BlueScreen HC is a human cell-based reporter assay that monitors expression of the GADD45a gene, a P53 target that is up- ... Gentronix is pleased to announce the introduction of its new early genotoxicity screening assay BlueScreen HC. ... Gentronix has also announced the introduction of its in vitro Comet assay service. The in vitro Comet assay can provide insight ...
Comet) Assay. International Journal of Pharmacology, 12: 169-176.. DOI: 10.3923/ijp.2016.169.176 URL: https://scialert.net/ ...
  • In early 2018, The Oxford University Press, together with United Kingdom Environmental Mutagen Society, composed a special comet assay issue of the Mutagenesis journal. (scorecomets.com)
  • This book documents the latest research and showcases the versatile, state-of-the-art technique - the Comet assay - in the field of modern toxicology. (rsc.org)
  • The Comet Assay in Toxicology is the first book of its kind to be devoted exclusively to the Comet assay and its applications as an important tool in modern toxicology. (rsc.org)
  • This section sets the scene by explaining why the assay has become the most sensitive and sought after assay in modern toxicology. (rsc.org)
  • The third section puts together the specific applications of the assay in the diverse fields ranging from genetic toxicity testing to human monitoring, and environmental toxicology. (rsc.org)
  • Single cell gel/comet assay: guidelines for in vitro and in vivo genetic toxicology testing. (sigmaaldrich.com)
  • The purpose of this article is to summarize the in vivo genotoxicity in eight organs of the mouse of 208 chemicals selected from International Agency for Research on Cancer (IARC) Groups 1, 2A, 2B, 3, and 4, and from the U.S. National Toxicology Program (NTP) Carcinogenicity Database, and to discuss the utility of the comet assay in genetic toxicology. (nih.gov)
  • Zhong Y,Feng S L,Luo Y,Zhang G D,Kong Z M. Evaluating the genotoxicity of surface water of Yangzhong City,using the micronucleus test of Vicia faba and the comet assay [J].Bulletin of Environmental Contamination and Toxicology,2001,(02):217-224. (wanfangdata.com.cn)
  • Devaux A,Pesonen M,Monod G. Alkaline comet assay in rainbow trout hepatocytes [J].Toxicology in Vitro,1997.71-7910.1016/S0887-2333(97)00004-0. (wanfangdata.com.cn)
  • Cells were treated with cigarette smoke condensate (CSC) for 72 h to assess the formation of single- and double-strand DNA breaks, measured by alkaline and neutral single cell gel electrophoresis assays, respectively. (pubmedcentralcanada.ca)
  • The mutagenic∕ genotoxic activities were evaluated by the Ames test on Salmonella typhimurium strains TA98, TA97a, TA100 and TA102, and the comet assay, so as to assess the safe use of HK in the treatment of Chagas' disease. (biomedcentral.com)
  • In light of the good trypanosomicidal activity of HK and given that natural products are promising sources of novel potentially therapeutic agents, the aim of the present study was to investigate its mutagenic and genotoxic activities by the Ames and comet assays, respectively, to assess the safety of using HK in the treatment of Chagas' disease. (biomedcentral.com)
  • The two laboratories that reported discordant results (with another cell line having the highest level of DNA-repair activity) were those that reported to have little experience with the modified comet assay to assess DNA repair. (ku.dk)
  • The comet assay (single-cell gel electrophoresis) is a simple method for measuring deoxyribonucleic acid (DNA) strand breaks in eukaryotic cells. (wikipedia.org)
  • The specificity of the Comet assay was improved by coupling the assay to 8-oxoguanine-glycosylase (hOGG1), which by catalyzing the excision of 8-oxo-dGuo yields strand-breaks that are dependent upon this lesion. (aacrjournals.org)
  • This coupled-assay was validated by treating A549 cells with either the powerful oxidant (potassium bromate) or the methylating agent (MMS), as positive and negative controls, respectively and then measuring DNA-strand breaks or the amount of 8-oxo-dGuo formed. (aacrjournals.org)
  • DNA single strand breaks (SSBs) were detected using the single-cell gel assay (comet assay) with alkaline electrophoresis (pH 12.3) and quantified by measuring comet tail length (CTL) (microm). (oup.com)
  • The 99m Tc-MDP was not able to induce a significant DNA strand breaks increase in in vivo assays. (mdpi.com)
  • The Tissue Culture Core Facilty now offers Comet Assays for measuring DNA strand breaks in individual cells. (utmb.edu)
  • Perceptive Instruments Comet Assay IV image analysis systems have been sited within peer-reviewed publications hundreds of times. (scorecomets.com)
  • The tails were evaluated through Comet Assay IV analysis software ( Perceptive Instruments Ltd ) and Camera AVT smart view for, Fire Package version 1.6.2) to measure the total image fluorescence intensity, head intensity, tail intensity, head length and tail length. (scorecomets.com)
  • Images of 50 randomly selected nuclei per experimental point were analyzed with image analysis software Comet Assay IV ( Perceptive Instruments , UK). (scorecomets.com)
  • Scoring was performed on a platform consisting of a Nikon 50i fluorescent microscope (Nikon, USA) and Comet IV digital imaging software ( Perceptive Instruments , Wiltshire, UK). (scorecomets.com)
  • DNA migration was determined with a computer aided comet assay image analysis system ( Comet Assay IV, Perceptive Instruments , UK). (scorecomets.com)
  • Microscopic images of comets were scored using Comet IV Computer Software ( Perceptive Instruments , UK). (scorecomets.com)
  • This results in structures resembling comets which by using suitable fluorescent stain, can be observed by fluorescent microscopy. (oecd.org)
  • The new BlueScreen HC assay provides a simple alternative for those screeners, profilers and safety toxicologists for whom fluorescence reporter systems are either not appropriate or not accessible, or where there is a preference for a luminescent rather than a fluorescent assay. (selectscience.net)
  • The position of the fluorescent hybridization spots in the comet head or tail indicates whether the sequence of interest lies within or in the vicinity of a damaged region of DNA. (elsevier.com)
  • A simple, non-lytic assay that allows real-time monitoring of apoptosis progression, without the need for multiple plates or complicated processing. (fishersci.com)
  • Anti-cancer drug candidates failing to induce apoptosis are likely to have decreased clinical efficacy, making apoptosis assays important tools for high-throughput drug screening. (thermofisher.com)
  • The kit components, number of assays and assay principles are summarized in Molecular Probes apoptosis assay kits-Table 15.4 . (thermofisher.com)
  • The lysis solution often used in the comet assay consists of a highly concentrated aqueous salt (often, common table salt can be used) and a detergent (such as Triton X-100 or sarcosinate ). (wikipedia.org)
  • CometAssay ® 96 Kit includes one specially treated CometSlide™ (96 Well) and sufficient reagents (Lysis Solution, LMAgarose, and 200 mM EDTA pH 8) for 96 test samples. (trevigen.com)
  • Comet parameters were compared between the cases and controls using Unpaired 't' test using the statistical software SPSS version 19. (alliedacademies.org)
  • Methods: Seventy infertile men and 40 fertile controls were evaluated for the semen quality by conventional semen parameters and the sperms were also analyzed for DNA integrity by comet assay. (who.int)
  • There was no significant difference between smokers and non-smokers in comet parameters. (ac.ir)
  • There was no significant correlation between Comet parameters and workload. (ac.ir)
  • There was direct and significant correlation between all parameters of comet. (ac.ir)
  • In our Lymphocyte Genome Sensitivity (LGS) assay, lymphocyte samples are embedded at different depths within the agar gel and irradiated with UVA in vitro. (news-medical.net)
  • Sensitivity and specificity of the empirical lymphocyte genome sensitivity (LGS) assay: implications for improving cancer diagnostics," FASEB J. 2014 Oct;28(10):4563-70. (news-medical.net)
  • Essentially, the PrimeFlow® RNA assay combines the analysis of gene and protein expression in a single application. (utdallas.edu)
  • We have compared the antioxidant activities of extracts from six anthocyanin-rich edible plants (red cabbage, red lettuce, blueberries, pansies, purple sweetpotato skin, purple sweetpotato flesh and Maori potato flesh) using three chemical assays (DPPH, TRAP and ORAC), and the in vitro Comet assay. (mdpi.com)
  • The extracts showed differential effects in the chemical assays, suggesting that closely related structures have different affinities to scavenge different reactive species. (mdpi.com)
  • Extracts of A. keiskei and, to a lesser extent O. javanica , inhibited two of the major enzymes that play a role in the metabolic activation of heterocyclic amines, based on ethoxyresorufin- O -deethylase and methoxyresorufin- O -demethylase assays in vitro . (pubmedcentralcanada.ca)
  • All three plant extracts were highly effective in assays which measured ferric reducing/antioxidant power, oxygen radical absorbance capacity, and Fe 2+ /H 2 O 2 -mediated DNA nicking. (pubmedcentralcanada.ca)
  • We evaluated the genotoxic effect of various concentrations of extracts of B. gaudichaudii and C. ferrea using comet assay of erythrocytes from Astyanax sp. (geneticsmr.com)
  • IMSEAR at SEARO: Comet assay: A prognostic tool for DNA integrity assessment in infertile men opting for assisted reproduction. (who.int)
  • Shamsi M B, Venkatesh S, Tanwar M, Singh G, Mukherjee S, Malhotra N, Kumar R, Gupta N P, Mittal S, Dada R. Comet assay: A prognostic tool for DNA integrity assessment in infertile men opting for assisted reproduction. (who.int)
  • This study was conducted to evaluate the potential induction of genotoxic effects of white bean flour using the Comet assay . (bvsalud.org)
  • Here we describe not only the comet assay step-by-step protocol, but also some important aspects related to troubleshooting. (researchsquare.com)
  • This protocol of Dr. Andrew Collins is from the Comet Assay Interest Group web site at http://cometassay.com/ . (neb.com)
  • In this study a modified version of the alkaline comet assay was used to evaluate the DNA crosslinks induced by mitomycin C (MMC) by determining the reduction of DNA migration following 5Gy -irradiation. (ulster.ac.uk)
  • Maori potato extract, consistently the weakest antioxidant in all the chemical assays, was more effective in the Comet assays. (mdpi.com)