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Abstrak :
In general, it was assumed that the chromosome aberration induced by ionizing radiation is proportional to the chromosome size. From this viewpoint, the higher chromosome size, the more resistant to radiation. However, different opinions, in which chromosomes are particularly sensitive or resistant to radiation, are also still followed until now. Here in this research, we compared the chromosome sensitivity between chromosomes number 1, 2, and 4 using the FISH (fluorescence in situ hybridization) technique. From this research, we expect that the information obtained could show clearly whether a longer chromosome is more frequently involved in translocations and also more resistant to radiation than a shorter one. The type of chromosome aberration considered was limited only to translocation and we used one sample donor in order to avoid donor variability. The whole blood from a healthy female was irradiated with γ-rays with doses of 1, 3 and 5 Gy, respectively. Isolated lymphocytes from the whole blood were then cultured for 48 hours. After the culture process was completed, preparations of harvest and metaphase chromosomes were carried out. Chromosomes 1, 2, and 4 were stained with different fluorochromes. The translocation of each chromosome at each dose point was subsequently evaluated from 50 images obtained from an automated metaphase finder and capturing system. An additional analysis was performed to identify which chromosome arm was more frequently involved in translocation. Further analyses were also conducted with the aim of determining which chromosome band had a higher frequency of radiation-induced breakage. The experimental results showed that chromosome number 4 was more frequently involved in translocations compared to chromosomes 1 and 2 at 5 Gy. In contrast, at doses of 1 and 3 Gy translocations involving chromosomes number 1 and 2 were more numerous compared to the ones involving chromosome 4. However, if the number of translocation was accumulated for all the doses applied, the chromosome number 4 was the chromosome most frequently involved in translocations. Breakpoint analysis revealed that in chromosome 1, chromosome 2, and chromosome 4, the highest chromosome bands as break position were in band q32, p13, and q21, respectively. It can be concluded that chromosome 4 is more sensitive to radiation in all doses point, despite having less DNA content than chromosomes 1 and 2. Thus, it was showed that our research cannot support the general assumption about chromosome aberration induced by radiation being proportional to DNA content.

Abstrak :
ABSTRAK
In vivo apoptosis of fibroblast pulp cells by ionizing radiation from radiotherapy of the head and neck area has not yet been demonstrated. The study aimed to show in vivo the effect of a single dose of ionizing radiation on apoptosis of fibroblast pulp cells. The sample group consisted of 24 healthy male Wistar rats that were 3-4 months old and 150- 200 g in weight. The rats were divided into 4 groups of 6 rats that were subjected to Cobalt 60 radiation to the head at the levels of 0, 100, 200 or 400 rad. The rats were sacrificed 24 hours after radiation exposure, and the lower incivus were taken for histopatological processing. Apoptosis was detected by using the TUNEL Assay method. The apoptotic fibroblast pulp cells were counted under light microscope by multiple observers using the blind test approach. The fraction of apoptotic cells was counted as mean of labial and palatal sides of the teeth below odontogenic and free-cell zone. The data were statistically analyzed using one-way anova. The results showed the percentage of apoptotic of fibroblast pulp cells was 6.4, 23.7, 34.5 and 17.8% after 0, 100, 200 and 400 rad doses, respectively. There were significant differences in the apoptotic percentages between the four groups (p<0.05). In conclusion, the highest fraction of apoptotic fibroblast pulp cells was found after a single 200 rad dose, and this fraction decreased after a single dose of 400 rad.

Abstrak :
Dalam penelitian ini, telah dilakukan pengukuran dosis ekuivalen di titik organ tiroid, sumsum tulang belakang, gonad dan jari tangan pada dua pekerja Instalasi Kedokteran Nuklir MRCCC Siloam serta pada dua pekerja RSPP. Hasilnya menunjukkan bahwa pengukuran telah berada di bawah nilai batas dosis (NBD) yang telah ditetapkan oleh IAEA dan BAPETEN dan penelitian ini dilakukan untuk mengetahui laju dosis serta aktivitas radiasi pengion untuk setiap kegiatan dari pekerja di Instalasi Kedokteran Nuklir MRCCC Siloam dan RSPP. Evaluasi dosis ekuivalen kumulatif selama 3 bulan pada setiap organ 4 pekerja memiliki range dosis 0.05 mSv hingga 0.11 mSv pada tiroid, 0.1 mSv hingga 0.19 mSv pada sumsum tulang belakang, 0.08 mSv hingga 0.14 mSv pada gonad dan 0.05 mSv hingga 0.24 mSv pada jari tangan. Hasil penelitian ini menunjukkan bahwa dosis ekuivalen yang diterima pekerja di Instalasi Kedokteran Nuklir MRCCC Siloam dan RSPP tidak melewati batasan dosis untuk pekerja radiasi yaitu 20 mSv/tahun. Pengukuran laju dosis sesaat radiasi pengion paling besar dari setiap kegiatan pekerja ketika menginjeksi radiofarmaka kepada pasien sebesar (25.03±26.57) μGy/hr. ...... Within this research, measurement of equivalent doses have been conducted on the thyroid points, bone marrow, gonads and fingers for two employees at Nuclear Installation of MRCCC Siloam and two employees at RSPP. The result show that it has been below of the dose limit value (NBD) as determined by IAEA and BAPETEN and the purpose of this reasearch is to determine the dose rate of ionizing radiation in all of the activities every day of employees in Nuclear Installation of MRCCC Siloam and RSPP. The evaluation for cumulative equivalent dose of employees for 3 months on organ at risk of 4 employees have range dose 0.05 mSv to 0.11 mSv on thyroid, 0.1 mSv to 0.19 mSv on bone marrow, 0.08 mSv to 0.14 mSv on gonads dan 0.05 mSv to 0.24 mSv on fingers. This results show that radiation dose evaluation for the radiation employees in Nuclear Installation of MRCCC Siloam and RSPP is not exceed of the dose limit from BAPETEN for the radiation employee that is 20 mSv/ year. Measurement of highest dose rate in all of the employee activities is on the employee injection of radiopharmaceutical to patient that is (25.03±26.57) μGy/hr.