natgillin/translations-raw huggingface dataset:
Sideløbende positive kontroller eller scoringskontroller bør fremkalde responser, der er forenelige med responserne i den historiske positive kontroldatabase, og medføre en statistisk set signifikant stigning sammenlignet med den negative kontrol (jf. punkt 20-21).
The micronucleus test (test method B.12) should be viewed as the in vivo test of choice for chromosomal aberrations when integration with other studies is desired.
Der er analyseret et passende antal doser og celler.
Bone marrow samples should be taken at two separate times following single treatments.
Kriterierne for valg af højeste dosis er i overensstemmelse med kriterierne i punkt 25-28.
For rodents, the first sampling interval should be the time necessary to complete 1,5 normal cell cycle lengths (the latter being normally 12-18 hours following the treatment period).
Evaluering og fortolkning af resultater
Since the time required for uptake and metabolism of the test chemical(s) as well as its effect on cell cycle kinetics can affect the optimum time for chromosomal aberration detection, a later sample collection 24 hours after the first sampling time is recommended.
Såfremt alle acceptkriterier er opfyldt, anses et testkemikalie for at være klart positivt, hvis:
At the first sampling time, all dose groups should be treated and samples collected for analysis; however, at the later sampling time(s), only the highest dose needs to be administered.
Mindst en af behandlingsgrupperne viser en statistisk signifikant stigning i frekvensen af celler med strukturelle kromosomaberrationer (uden gaps) sammenlignet med den sideløbende negative kontrol.
If dose regimens of more than one day are used based on scientific justification, one sampling time at up to approximately 1,5 normal cell cycle lengths after the final treatment should generally be used.
b. Denne stigning er dosisafhængig på mindst et prøveudtagningstidspunkt, når den evalueres med en passende trend test.
Following treatment and prior to sample collection, animals are injected intraperitoneally with an appropriate dose of a metaphase-arresting agent (e.g. colcemid or colchicine), and samples are collected at an appropriate interval thereafter.
c. Et hvilken som helst af disse resultater ligger uden for fordelingen af de historiske negative kontroldata (f.eks. Poisson-baserede kontrolgrænser på 95 %).
For mice this interval is approximately 3-5 hours prior to collection and for rats it is 2-5 hours.
Hvis det kun er den højeste dosis, der undersøges på et bestemt prøveudtagningstidspunkt, anses et testkemikalie for at være klart positivt, hvis der er en statistisk signifikant stigning sammenlignet med den sideløbende negative kontrol, og resultaterne ligger uden for fordelingen af de historiske negative kontroldata (f.eks. Poisson-baserede kontrolgrænser på 95 %).
Cells are harvested from the bone marrow, swollen, fixed and stained, and analysed for chromosomal aberrations (12).
Anbefalinger til hensigtsmæssige statistiske metoder kan findes i litteraturen (13).
Observations
Ved en dosis/respons-analyse bør mindst tre behandlede dosisgrupper analyseres.
General clinical observations of the test animals should be made and clinical signs recorded at least once a day, preferably at the same time(s) each day and considering the peak period of anticipated effects after dosing.
I de statistiske test bør dyret anvendes som forsøgsenhed.
At least twice daily during the dosing period, all animals should be observed for morbidity and mortality.
Positive resultater i testen for kromosomaberrationer viser, at testkemikaliet fremkalder strukturelle kromosomaberrationer i den testede arts knoglemarv.
All animals should be weighed at study initiation, at least once a week during repeated-dose studies, and at euthanasia.
Såfremt alle acceptkriterier er opfyldt, anses et testkemikalie for at være klart negativt, hvis følgende er opfyldt i alle de undersøgte forsøgsbetingelser:
In studies of at least one-week duration, measurements of food consumption should be made at least weekly.
Ingen af behandlingsgrupperne viser en statistisk signifikant stigning i frekvensen af celler med strukturelle kromosomaberrationer (uden gaps) sammenlignet med den sideløbende negative kontrol.
If the test chemical is administered via the drinking water, water consumption should be measured at each change of water and at least weekly.
b. Der er ingen dosisrelateret stigning på noget prøveudtagningstidspunkt, når dette vurderes i en egnet trend test.
Animals exhibiting non-lethal indicators of excessive toxicity should be humanely euthanised prior to completion of the test period (11).
c. Alle resultaterne ligger inden for fordelingen af de historiske negative kontroldata (f.eks. Poisson-baserede kontrolgrænser på 95 %).
Target tissue exposure
d. Knoglemarven blev eksponeret for testkemikaliet.
A blood sample should be taken at appropriate time(s) in order to permit investigation of the plasma levels of the test chemicals for the purposes of demonstrating that exposure of the bone marrow occurred, where warranted and where other exposure data do not exist (see paragraph 44).
Anbefalinger til de mest hensigtsmæssige statistiske metoder kan findes i litteraturen (13).
Bone marrow and chromosome preparations
Dokumentation for knoglemarvens eksponering for et testkemikalie kan omfatte et fald i mitoseindekset eller måling af plasma eller blodniveauer for testkemikaliet eller testkemikalierne.
Immediately after humane euthanasia, bone marrow cells are obtained from the femurs or tibias of the animals, exposed to hypotonic solution and fixed.
I tilfælde af intravenøs indgivelse er der ikke behov for dokumentation for eksponering.
The metaphase cells are then spread on slides and stained using established methods (see (3) (12)).
Alternativt kan der anvendes ADME-data indsamlet i en uafhængig undersøgelse under anvendelse af den samme metode og de samme arter til påvise knoglemarvseksponering.
All slides, including those of positive and negative controls, should be independently coded before analysis and should be randomised so the scorer is unaware of the treatment condition.
Negative resultater viser, at testkemikaliet under testbetingelserne ikke fremkalder strukturelle kromosomaberrationer i den testede arts knoglemarv.
The mitotic index should be determined as a measure of cytotoxicity in at least 1000 cells per animal for all treated animals (including positive controls), untreated or vehicle/solvent negative control animals.
Der er ikke krav om verifikation af en klart positiv eller negativ respons.
At least 200 metaphases should be analysed for each animal for structural chromosomal aberrations including and excluding gaps (6).
Hvis responsen hverken er klart negativ eller positiv og for at bidrage til at fastslå den biologiske relevans af et resultat (f.eks. en svag eller usikker stigning), bør dataene evalueres af eksperter, og/eller der bør foretages yderligere undersøgelser af de afsluttede forsøg.
However, if the historical negative control database indicates the mean background structural chromosomal aberration frequency is < 1 % in the testing laboratory, consideration should be given to scoring additional cells.
I nogle tilfælde kan det være nyttigt at analysere flere celler eller foretage en ny undersøgelse under anvendelse af modificerede forsøgsbetingelser.
Chromatid and chromosome-type aberrations should be recorded separately and classified by sub-types (breaks, exchanges).
I sjældne tilfælde, selv efter yderligere undersøgelser, giver dataene ikke mulighed for at konkludere, om testkemikaliet fremkalder enten positive eller negative resultater, og konklusionen er derfor, at undersøgelsen er tvetydig.
Recognising that slide preparation procedures often result in the breakage of a proportion of metaphases with a resulting loss of chromosomes, the cells scored should, therefore, contain a number of centromeres not less than 2n ± 2, where n is the haploid number of chromosomes for that species.
Hyppigheden af polyploide og endofordoblede metafaser blandt de samlede metafaser bør registreres særskilt.
Treatment of Results
En forøgelse af antallet af polyploide/endofordoblede celler kan være tegn på, at testkemikaliet kan inhibere mitotiske processer eller cellecyklussens forløb (jf. punkt 3).
Individual animal data should be presented in tabular form.
Testrapport
The mitotic index, the number of metaphase cells scored, the number of aberrations per metaphase cell and the percentage of cells with structural chromosomal aberration(s) should be evaluated for each animal.
Resumé
Different types of structural chromosomal aberrations should be listed with their numbers and frequencies for treated and control groups.
oprindelse, batchnummer, frist for anvendelse, hvis dette foreligger
Gaps, as well as polyploid cells and cells with endoreduplicated chromosomes are recorded separately.
testkemikaliets stabilitet, hvis kendt.
The frequency of gaps is reported but generally not included in the analysis of the total structural aberration frequency.
Præparering af testkemikaliet:
If there is no evidence for a difference in response between the sexes, the data may be combined for statistical analysis.
begrundelse for valg af bærestof
Data on animal toxicity and clinical signs should also be reported.
testkemikaliets opløselighed og stabilitet i opløsningsmidlet/bærestoffet, hvis dette er kendt
The following criteria determine the acceptability of the test:
fastlæggelse af sammensætning af føde, drikkevand eller inhalationsformulering
The concurrent negative control data are considered acceptable for addition to the laboratory historical control database (see paragraphs 11-14);
analytiske bestemmelser af formuleringer (f.eks. stabilitet, homogenitet og nominel koncentration), når disse foretages.
The concurrent positive controls or scoring controls should induce responses that are compatible with those generated in the historical positive control database and produce a statistically significant increase compared with the negative control (see paragraphs 20-21);
anvendt art/stamme og begrundelse herfor
The appropriate number of doses and cells has been analysed;
dyrenes antal, alder og køn
The criteria for the selection of highest dose are consistent with those described in paragraphs 25-28.
kilde, miljøbetingelser, føde mv.
Evaluation and Interpretation of Results
metode til entydig identifikation af dyr
Providing that all acceptability criteria are fulfilled, a test chemical is considered clearly positive if:
positive og negative (bærestof/opløsningsmiddel) kontrolgrupper
At least one of the treatment groups exhibits a statistically significant increase in the frequency of cells with structural chromosomal aberrations (excluding gaps) compared with the concurrent negative control,
data fra en eventuel forprøve til bestemmelse af dosisinterval
This increase is dose-related at least at one sampling time when evaluated with an appropriate trend test, and
begrundelse for valg af dosisniveau
Any of these results are outside the distribution of the historical negative control data (e.g. Poisson-based 95 % control limits).
oplysninger om præparering af testkemikaliet
If only the highest dose is examined at a particular sampling time, a test chemical is considered clearly positive if there is a statistically significant increase compared with the concurrent negative control and the results are outside the distribution of the historical negative control data (e.g. Poisson-based 95 % control limits).
oplysninger om indgivelse af testkemikaliet
Recommendations for appropriate statistical methods can be found in the literature (13).
begrundelse for indgivelsesvej og -varighed
When conducting a dose-response analysis, at least three treated dose groups should be analysed.
metoder til kontrol af, at testkemikaliet eller testkemikalierne er nået frem til det almindelige kredsløb eller knoglemarven
Statistical tests should use the animal as the experimental unit.
faktisk dosis (mg/kg kropsvægt/dag) beregnet på baggrund af testkemikaliets koncentration i føde/drikkevand (ppm) og fødeoptagelse, hvis dette er relevant
Positive results in the chromosomal aberration test indicate that a test chemical induces structural chromosomal aberrations in the bone marrow of the species tested.
oplysninger om foder og vandkvalitet
Providing that all acceptability criteria are fulfilled, a test chemical is considered clearly negative if in all experimental conditions examined:
aflivningsmetode
None of the treatment groups exhibits a statistically significant increase in the frequency of cells with structural chromosomal aberrations (excluding gaps) compared with the concurrent negative control,
analgesimetode (hvis anvendt)
There is no dose-related increase at any sampling time when evaluated by an appropriate trend test,
detaljeret beskrivelse af behandling og prøveudtagningsplaner samt begrundelser for valg
All results are inside the distribution of the historical negative control data (e.g. Poisson-based 95 % control limits), and
metoder til præparering af objektglas
Bone marrow exposure to the test chemical(s) occurred.
metoder til måling af toksicitet
Recommendations for the most appropriate statistical methods can be found in the literature (13).
det metafasestandsende kemikalies identitet, koncentration, dosis og tidspunkt for indgivelse før prøveudtagning
Evidence of exposure of the bone marrow to a test chemical may include a depression of the mitotic index or measurement of the plasma or blood levels of the test chemical(s).
procedurer for isolering og bevaring af prøver
In the case of intravenous administration, evidence of exposure is not needed.
antal analyserede metafaseceller pr. dyr og antal analyserede celler med henblik på mitoseindeksbestemmelse
Alternatively, ADME data, obtained in an independent study using the same route and same species can be used to demonstrate bone marrow exposure.
kriterier for accept af undersøgelsen
Negative results indicate that, under the test conditions, the test chemical does not induce structural chromosomal aberrations in the bone marrow of the species tested.
kriterier for bedømmelse af undersøgelsen som positiv, negativ eller usikker.
There is no requirement for verification of a clear positive or clear negative response.
dyrenes tilstand før og i løbet af testperioden, herunder tegn på toksicitet
In cases where the response is not clearly negative or positive and in order to assist in establishing the biological relevance of a result (e.g. a weak or borderline increase), the data should be evaluated by expert judgement and/or further investigations of the existing experiments completed.
mitoseindeks, anført særskilt for hvert dyr
In some cases, analysing more cells or performing a repeat experiment using modified experimental conditions could be useful.
antal aberrationer og aberrationsceller og type, anført særskilt for hvert dyr
In rare cases, even after further investigations, the data will preclude making a conclusion that the test chemical produces either positive or negative results, and the study will therefore be concluded as equivocal.
antal celler med aberrationer pr. gruppe med gennemsnit og standardafvigelse
An increase in the number of polyploid/endoreduplicated cells may indicate that the test chemical has the potential to inhibit mitotic processes or cell cycle progression (see paragraph 3).
eventuelt observerede ploidiændringer, herunder frekvenser for polyploide og/eller endofordoblede celler
Test Report
dosis/respons-forhold, hvor muligt
Summary
statistiske analyser og anvendt metode
source, lot number, limit date for use if available;
data for, at eksponering af knoglemarven fandt sted
stability of the test chemical, if known.
sideløbende negative og positive kontroldata med angivelse af intervaller, gennemsnit og standardafvigelser
Test chemical preparation:
historisk negative og positive kontroldata med angivelse af intervaller, gennemsnit og standardafvigelser og kontrolgrænser på 95 % for fordelingen, samt tidsperiode og antal observationer
justification for choice of vehicle;
opfyldte kriterier for en positiv eller negativ respons.
solubility and stability of the test chemical in solvent/vehicle, if known;
Konklusion.
preparation of dietary, drinking water or inhalation formulations;
Referencer.
analytical determinations on formulations (e.g. stability, homogeneity, nominal concentrations), when conducted.
, “Cytogenetic Tests in Mammals”, in Mutagenicity Testing: A Practical Approach, Venittand, S., J.M. Parry (eds.), IRL Press, Washington, DC, pp.
species/strain used and justification for use;
275-306.
number, age and sex of animals;
Part I revised, Kirkland, D.J. (ed.), Cambridge University Press, Cambridge, pp.
source, housing conditions, diet, etc.;
115-141.
method for uniquely identifying the animals;
UKEMS SubCommittee on Guidelines for Mutagenicity Testing, Report, Part III, Kirkland, D.J. (ed.), Cambridge University Press, Cambridge, pp.
for short-term studies: individual weight of the animals at the start and end of the test; for studies longer than one week: individual body weights during the study and food consumption.
184-232.
Body weight range, mean and standard deviation for each group should be included.
Enhver afvigelse fra det normale diploide (eller haploide) kromosomtal af et eller flere kromosomer, men ikke af et eller flere komplette kromosomsæt (jf. polyploidi)
positive and negative (vehicle/solvent) controls;
Centromer
data from range-finding study, if conducted;
Region(er) af et kromosom, hvortil tentrådene er påhæftet under celledeling, således at datterkromosomerne kan ordnes i forhold til dattercellernes poler.
rationale for dose level selection;
Beskadigelse af kromosomstrukturen i form af brud på enkeltkromatider eller brud på og sammenføjning af kromatider.
details of test chemical preparation;
Beskadigelse af kromosomstrukturen i form af brud på — eller brud på og sammenføjning af — begge kromatider på samme sted.
details of the administration of the test chemical;
En proces, hvorved cellekernen efter en S-fase i DNA-replikationen ikke fortsætter over i mitosen, men påbegynder endnu en S-fase.
rationale for route and duration of administration;
Resultatet er kromosomer med 4, 8, 16, ... kromatider.
methods for verifying that the test chemical(s) reached the general circulation or bone marrow;
En kromatisk beskadigelse, som er mindre end bredden af et kromatid, og hvor forskydningen af kromatiderne er minimal.
actual dose (mg/kg body weight/day) calculated from diet/drinking water test chemical concentration (ppm) and consumption, if applicable;
Mitoseindeks (MI)
details of food and water quality;
Forholdet mellem antallet af celler i mitose og det samlede antal celler i en population, som er et mål for cellepopulationens spredning.
method of euthanasia;
Ændring i kromosomtallet i forhold til det for de pågældende dyr normale antal (aneuploidi).
method of analgesia (where used);
Antalsmæssige kromosomaberrationer, der indebærer en ændring i antallet af det samlede kromosomsæt, i modsætning til en antalsmæssig ændring i en del af kromosomsættet (jf. aneuploidi).
detailed description of treatment and sampling schedules and justifications for the choices;
Strukturel kromosomaberration
methods of slide preparation;
Ændring i kromosomstrukturen, som kan iagttages ved mikroskopi i celledelingens metafase i form af deletioner og fragmenter, intrachange og interchange.
methods for measurement of toxicity;
FAKTORMODEL TIL IDENTIFIKATION AF KØNSBETINGEDE FORSKELLE I IN VIVO-KROMOSOMABERRATIONASSAYET
identity of metaphase arresting chemical, its concentration, dose and time of administration before sampling;
Faktormodellen og dens analyse
procedures for isolating and preserving samples;
I denne model testes mindst fem hanner og fem hunner på hvert koncentrationsniveau, hvilket betyder, at der med denne model anvendes mindst 40 dyr (20 hanner og 20 hunner plus relevante positive kontroller).
number of metaphase cells analysed per animal and the number of cells analysed for mitotic index determination;
Modellen, som er en af de enklere faktormodeller, svarer til en tovejsanalyse af varians med køn og koncentration som de primære virkninger.
criteria for acceptability of the study;
Dataene kan analyseres ved hjælp af mange statistiske standardsoftwarepakker som SPSS, SAS, STATA, Genstat, samt under anvendelse af R.
criteria for considering studies as positive, negative or inconclusive.
Hvert forhold testes mod et estimat af variationen mellem replikate dyr inden for grupper af dyr af samme køn ved samme koncentration.
mitotic index, given separately for each animal;
Fuldstændige oplysninger om den underliggende metode fås i mange statistiske standardlærebøger (jf. referencer) og i hjælpefunktionerne i de statistiske pakker.
type and number of aberrations and of aberrant cells, given separately for each animal;
Analysen fortsætter med at opdele skønnet af variationen mellem koncentrationer i kontraster, som giver en test for lineære og kvadratiske kontraster mellem respons på tværs af koncentrationsniveauerne.
changes in ploidy, if seen, including frequencies of polyploid and/or endoreduplicated cells;
Hvis der er en betydelig interaktion mellem køn og koncentration, kan denne interaktion også inddeles i lineære kontraster x køn og kvadratiske kontraster x køn.
dose-response relationship, where possible;
Dette giver test af, om koncentrationsresponserne er parallelle for de to køn, eller om der er en differentieret respons mellem dem.
statistical analyses and method applied;
Skønnet over den samlede variation i gruppen kan bruges til parvise test af forskellen mellem medianer.
data supporting that exposure of the bone marrow occurred;
Disse sammenligninger kan foretages mellem medianerne for de to køn og mellem medianerne for de forskellige koncentrationsniveauer såsom for sammenligninger med de negative kontrolniveauer.
concurrent negative control and positive control data with ranges, means and standard deviations;
I de tilfælde hvor der er en væsentlig interaktion, kan der foretages sammenligninger mellem medianerne for de forskellige koncentrationer inden for samme køn eller medianerne for de to køn ved samme koncentration.
historical negative and positive control data with ranges, means, standard deviations, and 95 % control limits for the distribution, as well as the time period covered and number of observations;
Referencer
criteria met for a positive or negative response.
Der findes mange statistiske lærebøger, som diskuterer teori, model, metode, analyse og fortolkning af faktormodeller, lige fra enkle to-faktor-analyser til de mere komplekse modeller, som anvendes ved Design of Experiment-metoder.
Conclusion.
Her følger en ikke-udtømmende liste.
References.
Statistikere, der anvender en modelleringsmetode såsom f.eks. lineære normale modeller (General Linear Models, GLM) kan have en anden, men sammenlignelig tilgang til analysen, men når ikke nødvendigvis frem til den traditionelle ANOVA-tabel, der er baseret på algoritmiske metoder til beregning af statistik udviklet før computerens indtog.
Parry (eds.), IRL Press, Washington, DC, pp. 275-306.
Del B, kapitel B.12, affattes således:
, “In Vivo Cytogenetics Assays”, in Basic Mutagenicity Tests, UKEMS Recommended Procedures.
Test for mikrokerner i erythrocytter hos pattedyr
Part I revised, Kirkland, D.J.
Denne forsøgsmetode svarer til OECD-testvejledning (Test Guideline) 474 (2016).
(ed.), Cambridge University Press, Cambridge, pp. 115-141.
En in vivo-test for mikrokerner hos pattedyr anvendes til at påvise beskadigelse af kromosomerne eller mitoseapparatet hos erythroblaster forårsaget af testkemikaliet.
OECD (2000), “Guidance Document on the Recognition, Assessment and Use of Clinical Signs as Humane Endpoints for Experimental Animals Used in Safety Evaluation”, OECD Environment, Health and Safety Publications (EHS), Series on Testing and Assessment, No19, OECD Publishing, Paris.
Testen vurderer dannelsen af mikrokerner i de udtagne erythrocytter, enten i knoglemarven eller det perifere blod hos dyr, sædvanligvis gnavere.
, “Statistical Analysis of in vivo Cytogenetic Assays”, in Statistical Evaluation of Mutagenicity Test Data.