ASTM E1202-87(2008)
(Guide)Standard Guide for Development of Micronucleus Assay Standards (Withdrawn 2013)
Standard Guide for Development of Micronucleus Assay Standards (Withdrawn 2013)
SIGNIFICANCE AND USE
Micronucleus assays for genetic damage have been developed in many types of eucaryotic cells, both in vitro and in vivo. The occurrence of micronuclei is indicative of chromosomal damage or mitotic spindle dysfunction.
SCOPE
1.1 This guide covers minimal criteria which should be met by a micronucleus assay system prior to the development of an ASTM Standard or Guide for the conduct of that assay.
1.2 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.
WITHDRAWN RATIONALE
Formerly under the jurisdiction of Committee F04 on Medical and Surgical Materials and Devices, this guide was withdrawn in October 2013. This standard is being withdrawn without replacement because more detailed methods have since been developed and approved.
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NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.
Contact ASTM International (www.astm.org) for the latest information
Designation: E1202 − 87(Reapproved 2008)
Standard Guide for
1
Development of Micronucleus Assay Standards
This standard is issued under the fixed designation E1202; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
1. Scope aberrations or chromosome loss or both, and not apoptosis or
any other mechanism.
1.1 This guide covers minimal criteria which should be met
3.2 Time Response:
by a micronucleus assay system prior to the development of an
3.2.1 The “expression time” for micronuclei should be
ASTM Standard or Guide for the conduct of that assay.
characterized for (a) direct-acting genotoxins and (b) genotox-
1.2 This standard does not purport to address all of the
ins requiring metabolic activation.
safety concerns, if any, associated with its use. It is the
3.3 Dose Response:
responsibility of the user of this standard to establish appro-
3.3.1 The dose response curves for several classes of
priate safety and health practices and determine the applica-
genotoxins, over a dose range including both toxic and
bility of regulatory limitations prior to use.
nontoxic doses, should be known. A rational method for
2. Significance and Use determining the upper and lower doses to be tested should be
available.
2.1 Micronucleus assays for genetic damage have been
3.4 Spontaneous Frequency:
developed in many types of eucaryotic cells, both in vitro and
3.4.1 The spontaneous frequency of micronuclei should be
in vivo. The occurrence of micronuclei is indicative of chro-
well characterized and should be stable under the test condi-
mosomal damage or mitotic spindle dysfunction.
tions employed. Major factors affecting the spontaneous inci-
3. Criteria dence of micronuclei should be defined.
3.5 Statistics:
3.1 Biology:
3.1.1 The biology of the system should be well understood 3.5.1 The following statistical criteria should be met:
3.5.1.1 There should be sufficient data to define the major
in terms of (a) cell cycle, (b ) metabolic capabilities, (c) culture
sources of experimental variability (for example, slide to slide,
or growth conditions, and (d) other factors of importance in
animal to animal), in order to permit rational experimental
maintaining a reproducible experimental situation. There
design,
should be evidence that micronuclei arise from chromosomal
3.5.1.2 Appropriate statistical methods for analyzing the
data should be available,
1
3.5.1.3 Sufficient data and adequate statistical methods
This guide is under the jurisdiction of ASTM Committee F04 on Medica
...
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Devising robust methods for measuring the propensity of cells to attach to different substrates is further complicated since either cell adhesion or detachment can be assessed. These processes that are not always similar or complementary.
Most studies of cell attachment focus on obtaining some measure of the time-dependent force required to detach, or de-adhere, cells that have already adhered to a surface (James et al, 2005) (7). More recently investigators have begun to measure the adhesive forces that develop between cells and the underlying surface during attachment (Lukas and Dvorak, 2004) (5). From a practical point of view, it is much easier to measure the force required to detach or de-adhere cells from a surface than to measure those that develop during attachment. However, in both cases, the experimental data should be interpreted with a degree of caution that depends on the intended use of the measurements. The methods of measuring cell adhesion described herein are measures of the force required to detach an...
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