No abstract available

No abstract available

[en] Chromosome aberrations are used to estimate the doses of radiation received from occupational or accidental exposure. Dicentric Chromosome Assay (DCA) is used to determine the dose by count the number of unstable Chromosome Aberration. The type of unstable chromosome was count in this study are dicentric, ring and fragment. Slides with doses 0.1 Gy, 0.5 Gy, 2.0 Gy and 3.0 Gy were choose. Each slide scanned to find the aberration in low and high dose. Type of aberration were classified, count and recorded. Result in this study show which type of aberration found most in lower and high dose. Dicentric and centric ring found in most high dose, meanwhile fragment found in every dose studied. Dicentric with fragment or ring with fragment, count as one set. (author)

No abstract available

[en] Full-text:Cytokinesis Block Micronucleus (CBMN) Assay is a simple and an alternative way for indicator of chromosome damage. In a large radiation accident, CBMN Assay can be early detect for chromosome damage before we do aberration chromosome assay. After completing 72 hours incubation, cell was harvest and dropped into the slide and will do pre- treatment with RNase A. RNase as an agent to remove residual stainable cytoplasmic material, which will be background of the cell clear. Clear background help to easier in analysis of micronuclei (MN). The diameter of MN usually between 1/16th and 1/3rd of the mean diameter of the main nuclei. The clear image of background useful for slides assessed with automatic image analysis system. (author)

[en] The International Atomic Energy Agency (IAEA) has recommended that incubation time for the hypotonic treatment of lymphocytes in dicentric assay technique to be between 15 to 20 minutes. Incubation time will effect the hypotonic treatment of lymphocytes and thus, the breakage of cytoplasmic membrane. The objective of this study is to examine the effect of varying incubation times for hypotonic treatment of lymphocytes in dicentric assay technique. In this study, we choose to use our standard protocol for dicentric assay technique. However, for the hypotonic treatment of lymphocytes, the incubation times were varied from 10, 15, 20, 25 and 30 minutes respectively. Lymphocytes were then fixed and stained with Giemsa. The cells were then analyzed for clear background that indicates good metaphases. We found that incubation time of 30 minutes gives the best metaphase images. This incubation time is longer than what has been recommended by the IAEA. This maybe explained by the fact that our country's climate is of higher humidity compared with the European countries. (author)

[en] Autoclave is a common equipment found in most microbiology laboratories in hospitals, universities, research institutes as well as food, dairy and pharmaceutical product manufacturing facilities. The main function of this equipment is to sterilize glass apparatus, biological media and medical devices. In addition, it is also used for decontamination of biological wastes. Autoclave validation is a quality assurance procedure used to ensure that the autoclave has reached a sufficient temperature for an adequate amount of holding time to sterilize biological agents and wastes. To ensure that this sterilization process is successful, several steps can be taken either by using a datalogger, biological indicator or chemical indicator. In this experiment, the sterilization process was carried out on several types of samples using biological indicators containing Geobacillus stearothermophilus bacteria ATCC 7953. The results of this experiment are very important because they provide information on whether the selected parameters are suitable for the capacity of the product which indirectly affects the overall sterilization process. The autoclave validation process is also one of the procedures that must be done to comply with Good Manufacturing Practices (GMP) guidelines. (author)

[en] Dicentric assay is the international gold standard for cytogenetic biodosimetry after radiation exposure. This technique required time consuming, labour-intensive and highly expertise-dependent. It involves the identification of centromeres and structure of solid-stained chromosomes and the enumeration of dicentric chromosomes in metaphase cells of cultured lymphocytes. The dicentric yield is used to estimate the radiation exposure dosage according to a statistically derived and predetermined dose-response curve. Aim of the study is to analyze the dicentric chromosome using automated microscope integrated with metaphase finder software. Cells obtained after a dicentric technique process, are color using Giemsa stained. Slides were placed on automated stage and scanning under 10x objective lens. Cells with 46 of chromosome are selected and then captured under 63x objective lens. The software identifies and counts dicentric chromosomes automatically. Identification of dicentric chromosomes is done based on morphology criteria. All detected dicentric chromosomes are highlighted in the metaphase and recorded in scoring sheet. Enumeration of dicentric chromosome using automated microscope and metaphase finder is simple, fast and the results are highly reproducible. Therefore, this equipment is very helpful to estimate the radiation dose and suitable for a mass casualty event. (author)

[en] This study aims at establishing an in-vitro ⁶⁰Co dose calibration curve using Fluorescent In-Situ Hybridization assay technique for the Malaysian National Bio dosimetry Laboratory. Blood samples collected from a female healthy donor were irradiated with several doses of ⁶⁰Co radiation. Following culturing of lymphocytes, microscopic slides are prepared, denatured and hybridized. The frequencies of translocation are estimated in the metaphases. A calibration curve was then generated using a regression technique. It shows a good fit to a linear-quadratic model. The results of this study might be useful in estimating absorbed dose for the individual exposed to ionizing radiation retrospectively. This information may be useful as a guide for medical treatment for the assessment of possible health consequences. (author)

[en] Detection of chromosome at metaphase of the cell cycle is performed either manually or automatically. Procedure for slide preparation published by the IAEA does not guarantee that the quality of slide is suitable for automatic detection. The detection efficiency reduces if there is cells debris on slides. This paper describes the modifications made to the standard procedure. The period of hypotonic treatment to the cell was lengthened; the slides were pre-treated with RNase and the frequency of rinsing during the chromosomal coloring process was increased. Results show the metaphase images were better and clearer, and numbers of metaphase that can be detected automatically were also increased. In conclusion, modification to the current standard protocol helps to easy the process of chromosome aberration analysis at Nuclear Malaysia. (author)