natgillin/translations-raw huggingface dataset:
data for tidligere negative (opløsningsmiddel/bærestof) og positive kontrolprøver med angivelse af intervaller, gennemsnit og standardafvigelser
historical negative (solvent/vehicle) and positive control data with ranges, means and standard deviations,
mutanthyppighed
mutant frequency.
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Li, A.P., Carver, J.H., Choy, W.N., Hsie, A.W., Gupta, R.S., Loveday, K.S., O'Neill, J.P., Riddle, J.C., Stankowski, L.F.
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Yandell, D.W., Dryja, T.P. and Little, J.B., (1990) Molecular Genetic Analysis of Recessive Mutations at a Heterozygous Autosomal Locus in Human Cells.
(1990), Molecular Genetic Analysis of Recessive Mutations at a Heterozygous Autosomal Locus in Human Cells, Mutation Res., 229, pp. 89-102.
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Moore, M.M. and Doerr, C.L., (1990) Comparison of Chromosome Aberration Frequency and Small-Colony TK-Deficient Mutant Frequency in L5178Y/TK+/- - 3.7.2C Mouse Lymphoma Cells.
(1990), Comparison of Chromosome Aberration Frequency and Small-Colony TK-Deficient Mutant Frequency in L5178Y/TK+/- — 3.7.2C Mouse Lymphoma Cells, Mutagenesis 5, pp.609-614.
Mutagenesis, 5, p. 609-614.
Ved Unscheduled DNA Synthesis (UDS) test undersøges dna-reparationen efter bortskæring og fjernelse af skader, som er induceret af kemiske eller fysiske agentia.
The Unscheduled DNA Synthesis (UDS) test measures the DNA repair synthesis after excision and removal of a stretch of DNA containing the region of damage induced by chemical and physical agents.
Testen bygger på inkorporering af tritiummærket thymidin (3H-TdR) i pattedyrcellers dna, når disse celler ikke er i S-fase.
The test is based on the incorporation of tritium labelled thymidine (3H-TdR) into the DNA of mammalian cells, which are not in the S phase of the cell cycle.
Optagelsen af 3H-TdR kan måles ved autoradiografi eller væskescintillationstælling (LSC) af dna fra de eksponerede celler.
The uptake of 3H-TdR may be determined by autoradiography or by liquid scintillation counting (LSC) of DNA from the treated cells.
Medmindre der anvendes primærkulturer af rottehepatocytter, eksponeres dyrkede pattedyrceller for teststoffet med og uden et eksogen metabolisk aktiveringssystem.
Mammalian cells in culture, unless primary rat hepatocytes are used, are treated with the test agent with and without an exogenous metabolic activation system.
UDS-test kan også foretages i in vivo-systemer.
UDS may also be measured in in vivo systems.
Teststof samt kontrol- og referencestoffer tilsættes kulturmediet eller opløses eller suspenderes i egnede vehikler og tilsættes derefter kulturmediet inden testen.
Test chemicals and control or reference substances should be prepared in growth medium or dissolved or suspended in appropriate vehicles and then further diluted in growth medium for use in the assay.
Den derved opnåede vehikelkoncentration bør ikke påvirke cellernes levedygtighed.
The final concentration of the vehicle should not affect cell viability.
Der kan anvendes primærkulturer af rottehepatocytter, humane lymfocytter eller etablerede cellelinjer (f.eks. humane diploide fibroblaster).
Primary cultures of rat hepatocytes, human lymphocytes or established cell lines (e.g. human diploid fibroblasts) may be used in the assay.
Cellerne eksponeres for teststoffet med og uden et passende metabolisk aktiveringssystem.
Cells should be exposed to the test chemical both in the presence and absence of an appropriate metabolic activation system.
Antal kulturer
Number of cultures
Ved autoradiografisk påvisning af UDS anvendes mindst to og ved LSC seks kulturer (eller mindre hvis det er videnskabeligt begrundet) for hvert eksperimentelt punkt.
At least two cell cultures for autoradiography and six cultures (or less if scientifically justified) for LSC UDS determinations are necessary for each experimental point.
Der foretages sideløbende både positiv og negativ (ubehandlet og/eller vehikel) kontrol med og uden metabolisk aktivering i hvert forsøg.
Concurrent positive and negative (untreated and/or vehicle) controls with and without metabolic activation should be included in each experiment.
Som positiv kontrol ved anvendelse af rottehepatocytter kan f.eks. benyttes 7,12-DMBA (7,12-dimetylbenzanthracen) eller 2-AAF (2-acetylaminofluoren).
Examples of positive controls for the rat hepatocyte assay include 7,12- dimethylbenzathracene (7,12- DMBA) or 2-acetylaminofluorene (2-AAF).
Som positiv kontrol ved anvendelse af etablerede cellelinjer kan f.eks. benyttes 4-NQO (4-nitroquinolin-N-oxid) både i forbindelse med autoradiografisk registrering og LSC uden metabolisk aktivering. Når der anvendes metaboliske aktiveringssystemer kan f.eks. N-dimetylnitrosamin benyttes til positiv kontrol.
In the case of established cell lines 4-nitroquinoline-N-oxide (4-NQO) is an example of a positive control for both the autoradiographic and LSC assays performed without metabolic activation; N-dimethylnitrosamine is an example of a positive control compound when metabolic activation systems are used.
Der anvendes en række forskellige koncentrationer af teststoffet over et interval, som dækker alle påvirkninger.
Multiple concentrations of the test substance over a range adequate to define the response should be used.
Den højeste koncentration bør have en vis cytotoksisk virkning.
The highest concentration should elicit some cytotoxic effects.
Stoffer, som er relativt uopløselige i vand, testes op til opløselighedsgrænsen.
Relatively water-insoluble compounds should be tested up to the limit of solubility.
Den højeste koncentration af ikke-toksiske teststoffer, som er frit opløselige i vand, fastlægges fra test til test.
For freely water-soluble non-toxic chemicals, the upper test chemical concentration should be determined on a case-by-case basis.
Der benyttes passende vækstmedier, CO2-koncentration, temperatur og fugtighed til opretholdelse af kulturerne.
Appropriate growth media, CO2 concentration, temperature and humidity should be used in maintaining cultures.
Det undersøges regelmæssigt, om etablerede cellelinjer er kontamineret med mycoplasma.
Established cell lines should be periodically checked for Mycoplasma contamination.
Der anvendes ikke metaboliske aktiveringssystemer i forbindelse med primærkulturer af hepatocytter.
A metabolic activation system is not used with primary hepatocyte cultures.
Etablerede cellelinjer og lymfocytter eksponeres for teststoffer både med og uden et passende metabolisk aktiveringssystem.
Established cell lines and lymphocytes are exposed to test substance both in the presence and absence of an appropriate metabolic activation system.
Etablerede cellelinjer fremstilles på basis af stamkulturer (f.eks. ved trypsinering eller afrystning) og udsås med passende tæthed i dyrkningsskåle, hvorefter de inkuberes ved 37 oC.
Established cell lines are generated from stock cultures (e.g. by trypsinisation or by shaking off), seeded in culture vessels at appropriate density, and incubated at 37 oC.
Primære rottehepatocytkulturer etableres, når hepatocytter umiddelbart efter isolering anbringes i et passende medium og får lov til at hæfte sig til den voksende overflade.
Short-term cultures of rat hepatocytes are established by allowing freshly dissociated hepatocytes in an appropriate medium to attach themselves to the growing surface.
Humane lymfocytkulturer dyrkes under anvendelse af dertil egnede teknikker.
Human lymphocyte cultures are set up using appropriate techniques.
Eksponering af kulturerne for teststoffet
Treatment of the cultures with the test substance
Primærkulturer af rottehepatocytter
Primary rat hepatocytes
Rottehepatocytter eksponeres for teststoffet kort tid efter isolering i et passende tidsrum i et medium, som indeholder 3H-TdR.
Freshly isolated rat hepatocytes are treated with the test substance in a medium containing 3H-TdR for an appropriate length of time.
Efter eksponeringen fjernes cellerne fra mediet, hvorefter de vaskes, fikseres og tørres.
At the end of the treatment period, medium should be drained off the cells, which are then rinsed fixed and dried.
Pladerne dyppes i en autoradiografisk emulsion (alternativt kan »stripping« -film anvendes) og eksponeres, fremkaldes, farves og tælles.
Slides should be dipped in autoradiographic emulsion (alternative stripping film may be used), exposed, developed, stained and counted.
Etablerede cellelinjer og lymfocytter
Established cell lines and lymphocytes
Autoradiografisk teknik: Cellekulturerne eksponeres først for teststoffet i et passende tidsrum og derefter for 3H-TdR.
Autoradiographic techniques: cell cultures are exposed to the test substance for appropriate durations followed by treatment with 3H-TdR.
Eksponeringsperioderne afhænger af stofferne, de metaboliske aktiveringssystemer og celletyperne.
The times will be governed by the nature of the substance, the activity of metabolising systems and the type of cells.
Eksponeringen for 3H-TdR bør enten foregå samtidig med eksponeringen for teststoffet eller få minutter efter, således at UDS måles på det tidspunkt, hvor aktiviteten er størst.
To detect the peak of UDS, 3H-TdR should be added either simultaneously with the test subsrance or within a few minutes after exposure to the test substance.
Valget mellem de to fremgangsmåder afhænger af risikoen for interaktion mellem teststoffet og 3H-TdR.
The choice between these two procedures will be influenced by possible interactions between test substance and 3H-TdR.
Det er muligt at skelne mellem UDS og semi-konservativ dna replication, idet den sidstnævnte proces inhiberes ved anvendelse af f.eks. argininfattige medier, et lavt serumindhold eller tilsætning af hydroxyurinstof til kulturmediet.
In order to discriminate between UDS and semi-conservative DNA replication, the latter can be inhibited, for example, by the use of an arginine-deficient medium, low serum content or by hydroxyurea in the culture medium.
LSC-måling af UDS: Inden eksponering for teststoffet blokeres cellernes overgang til S-fasen som tidligere beskrevet. Derefter eksponeres cellerne på samme måde som ved den autoradiografiske teknik.
LSC measurements of UDS: prior to treatment with test substance, entry of cells into S-phase should be blocked as described above; cells should then be exposed to test chemical as described for autoradiography.
Umiddelbart efter inkubationen ekstraheres cellernes dna og det totale dna-indhold samt mængden af inkorporeret 3H-TdR måles.
At the end of the incubation period, DNA should be extracted from the cells and the total DNA content, and the extent of 3H-TdR, incorporation determined.
Når de nævnte teknikker anvendes på humane lymfocytter, er det unødvendigt at hæmme den semi-konservative dna replication, med mindre der er tale om stimulerede kulturer.
It should be noted that, where human lymphocytes are used in the above techniques, the suppression of semi-conservative DNA replication is unnecessary in unstimulated cultures.
Autoradiografisk måling
Autoradiographic determinations
Ved måling af UDS i dyrkede celler medregnes kerner i S-fasen ikke.
In determining UDS in cells in culture, S-phase nuclei are not counted.
Der tælles mindst 50 celler pr. koncentration.
At least 50 cells per concentration should be counted.
Objektglassene kodes før tællingen.
Slides should be coded before counting.
På hvert glas tælles en række forskellige tilfældigt valgte områder med stor indbyrdes afstand.
Several widely separated random fields should be counted on each slide.
Mængden af inkorporeret 3H-TdR i cytoplasmaet bestemmes ved tælling i tre områder på størrelse med kernen i hver optalt celles cytoplasma.
The amount of 3H-TdR incorporation in the cytoplasm should be determined by counting three nucleus-sized areas in the cyptoplasm of each cell counted.
LSC-måling
LSC determinations
Ved LSC-måling af UDS anvendes et passende antal kulturer pr. koncentration og pr. kontrolforsøg.
An adequate number of cultures should be used at each concentration and in the controls in LSC UDS determinations.
Data opstilles i tabelform.
Data should be presented in tabular form.
AUTORADIOGRAFISK MÅLING
AUTORADIOGRAPHIC DETERMINATIONS
Mængden af inkorporeret 3H-TdR i cytoplasmaet og antallet af korn, som registreres i cellekerneområdet, anføres separat.
The extent of 3H-TdR incorporation in the cytoplasm and the number of grains found over the cell nucleus should be recorded separately.
Fordelingen af mængden af inkorporeret 3H-TdR i cytoplasmaet og antallet af korn pr. kerne kan beskrives ved hjælp af middel, median og modus.
Mean, median and mode may be used to describe the distribution of the extent of 3H-TdR incorporation in the cytoplasm and the number of grains per nucleus.
LSC-MÅLING
LSC DETERMINATIONS
Ved LSC-måling angives 3H-TdR indlejringen som dpm/μg dna.
For LSC determinations, 3H-TdR incorporation should be reported as dpm/μg DNA.
Indlejringsfordelingen kan beskrives ved hjælp af middel dpm/μg dna med tilhørende standardafgivelse.
The mean dpm/μg DNA with standard deviation may be used to describe the distribution of incorporation.
Evalueringen af data baseres på passende statistiske metoder.
Data should be evaluated using appropriate statistical methods.
de anvendte celler, tæthed og antal passager på eksponeringstidspunktet, antal cellekulturer
cells used, density and passage number at time of treatment, number of cell cultures,
metoder til opretholdelse af cellekulturer, herunder medium, temperatur og CO2-koncentration
methods used for maintenance of cell cultures including medium, temperature and CO2 concentration,
teststof, vehikel, koncentrationer og begrundelse for valget af de anvendte koncentrationer
test substance, vehicle, concentrations and rationale for selection of concentrations used in the assay,
detaljerede oplysninger om de metaboliske aktiveringssystemer
details of metabolic activation systems,
eksponeringsplan
treatment schedule,
anvendt autoradiografiteknik
autoradiographic technique used,
fremgangsmåde ved blokering af cellernes overgang til S-fasen
procedures used to block entry of cells into S-phase,
fremgangsmåde ved ekstration af dna og bestemmelse af det totale dna-indhold ved LSC-målingen
procedures used for DNA extraction and determination of total DNA content in LSC determination,
om muligt dosis-responsforhold
dose/response relationship, where possible,
statistisk evaluering
statistical evaluation,
EVALUERING OG FORTOLKNING
VALUATION AND INTERPRETATION
Søsterkromatid ombytning (SCE) test er en korttidstest, som anvendes til påvisning af reciprok udveksling af DNA mellem de to søsterkromatider i et kromosom under replikation.
The Sister Chromatid Exchange (SCE) assay is a short-term test for the detection of reciprocal exchanges of DNA between two sister chromatids of a duplicating chromosome.
Ved SCE sker der en udveksling af dna replikationsprodukter ved tilsyneladende homologe loci.
SCEs represent the interchange of DNA replication products at apparently homologous loci.
Udvekslingsprocessen bygger antageligt på brud og genforening af dna-kæder, men dens molekylære grundlag er næsten ukendt.
The exchange process presumably involves DNA breakage and reunion, although little is known about its molecular basis.
For at kunne påvise SCE er det nødvendigt at differentialmærke søsterkromatiderne, hvilket kan gøres ved at inkorporere bromdeoxyuridin (BrdU) i kromosomernes dna gennem to cellecykler.
Detection of SCEs requires some means of differentially labelling sister chromatids and this can be achieved by incorporation of bromodeoxyuridine (BrdU) into chromosomal DNA for two cell cycles.
Pattedyrceller eksponeres in vitro for teststoffet med og uden et eksogent metabolisk aktiveringssystem fra pattedyr, hvis dette skønnes relevant, og dyrkes gennem to cellecykler i et medium, som indholder BrdU.
Mammalian cells in vitro are exposed to the test chemical with and without a mammalian exogenous metabolic activation system, if appropriate, and cultured for two rounds of replication in BrdU-containing medium.
Cellerne behandles med en tentrådsinhibitor (f.eks. colchicin) med henblik på at akkumulere celler på et metafaselignende trin i mitosen (c-metafase), hvorefter de høstes og præpareres til kromosomanalyse.
After treatment with a spindle inhibitor (e.g. colchicine) to accumulate cells in a metaphase-like stage of mitosis (c-metaphase), cells are harvested and chromosome preparations are made.