Analysis of cytogenetic indexes in interventional radiology workers exposed to low dose long-term chronic irradiation / 中国职业医学

OBJECTIVE: To observe the effect of low dose long-term chronic irradiation on chromosome aberration and micronucleus in peripheral blood lymphocytes of interventional radiology workers.METHODS: A total of 100 interventional radiology workers in a grade A tertiary hospital of Henan Province were selected as the interventional group using a convenient sampling method, and 78 healthy individuals without radiation exposure were selected as the control group. The incidence of chromosomal aberration and micronucleus of peripheral blood lymphocytes in individuals of these two groups were investigated. RESULTS: The frequencies of cells with acentric fragment(ace), dicentric chromosome(dic), reciprocal translocation(t), chromosome type aberration and total aberration in the interventional group were higher than those in the control group, and the differences were statistically significant(0.55% vs 0.30%, 0.25% vs 0.03%, 0.38% vs 0.01%, 1.21% vs 0.34%, 1.37% vs 0.54%, all P<0.01). In the interventional group, the frequency of cell with chromosome type aberration was higher than that of chromatid type aberration(1.21% vs 0.16%, P<0.01).The frequency of cell with unstable chromosome aberration was higher than that of stable chromosome aberration(0.80% vs 0.41%, P<0.01), and the frequency of cell with chromosomal type aberrant in the interventional group ranked from high to low in order of ace, t, dic and deletion(P<0.01). The incidence of micronuclear cells and micronucleus in the interventional group were higher than those in the control group(0.86‰ vs 0.40‰, 0.89‰ vs 0.41‰, all P<0.01). The incidence of micronuclear cells and micronucleus of female interventional radiology workers were higher than those of male workers(1.12‰ vs 0.62‰, 1.19‰ vs 0.62‰, all P<0.01).CONCLUSION: Low dose and long-term chronic irradiation exposure can affect both chromosome aberration and micronucleus of interventional radiology workers. The main chromosomal aberrations were non-stable chromosomal aberrations ace, dic and stable chromosomal aberrations t.

Identification and Validation of Candidate Radiation-responsive Genes for Human Biodosimetr / 生物医学与环境科学（英文）

The aim of the present study is to analyze the global research trend of radiation-responsive genes and identify the highly reproducible radiation-responsive genes. Bibliometric methods were applied to analyze the global research trend of radiation-responsive genes. We found 79 publications on radiation-responsive genes from 2000 to 2017. A total of 35 highly reproducible radiation-responsive genes were identified. Most genes are involved in response to DNA damage, cell proliferation, cell cycle regulation, and DNA repair. The p53 signal pathway was the top enriched pathway. The expression levels of 18 genes in human B lymphoblastoid cell line (AHH-1) cells were significantly up-regulated in a dose-dependent manner at 24 h after exposure to 0-5 Gy 60Co γ-ray irradiation. Our results indicate that developing a gene expression panel with the 35 high reproducibility radiation-responsive genes may be necessary for qualitative and quantitative assessment after exposure.

Identification of two novel mitochondrial DNA deletions induced by ionizing radiation / 生物医学与环境科学（英文）

<p><b>OBJECTIVE</b>We identify ionizing radiation-induced mitochondrial DNA (mtDNA) deletions in human lymphocytes and their distribution in normal populations.</p><p><b>METHODS</b>Long-range polymerase chain reactions (PCR) using two pairs of primers specific for the human mitochondrial genome were used to analyze the lymphoblastoid cell line following exposure to 10 Gy (60)Co γ-rays. Limited-condition PCR, cloning and sequencing techniques were applied to verify the mtDNA deletions detected with long-range PCR. Human peripheral blood samples were irradiated with 0, 2 and 6 Gy (60)Co γ-rays, and real-time PCR analysis was performed to validate the mtDNA deletions. In order to know the distribution of mtDNA deletions in normal population, 222 healthy Chinese adults were also investigated.</p><p><b>RESULTS</b>Two mtDNA deletions, a 7455-bp deletion (nt475-nt7929 in heavy strand) and a 9225-bp deletion (nt7714 -nt369 in heavy strand), occurring between two 8-bp direct repeats, were identified in lymphoblastoid cells using long-range PCR, limited-condition PCR and sequencing. These results were also observed for (60)Co γ-rays irradiated human peripheral blood cells.</p><p><b>CONCLUSION</b>Two novel mtDNA deletions, a 7455-bp deletion and a 9225-bp deletion, were induced by ionizing radiation. The rate of the mtDNA deletions within a normal population was related to the donors' age, but was independent of gender.</p>

Detection of chromosome aberrations in Chinese children with autism using G-banding and BAC FISH / 中华医学遗传学杂志

<p><b>OBJECTIVE</b>To detect the characteristic chromosomal changes in Chinese children with infantile autism.</p><p><b>METHODS</b>Chromosome aberrations in 68 cases of infantile autism were analyzed by high-resolution G-banding and fluorescence in situ hybridization (FISH) with bacterial artificial chromosome (BAC) clones.</p><p><b>RESULTS</b>Chromosomal changes were detected in 4 cases by high-resolution G-banding: one case with t(4;6)(q23-24;p21), one case with longer p arm of chromosome 21 (21p+), and two cases with pericentric inversion of chromosome 9 (inv(9)) which was confirmed by C-banding. BAC FISH analysis was performed to confirm these observations and changes in chromosomes 2, 7 and 15, which are often found in autistic children. There could exist the translocation of t(4;6) (q25-26;p21.1). Chromosome changes often reported previously in chromosomes 2, 7 and 15 were not detected in this study. Inv(9) and 21p+ were not confirmed with present BAC clones.</p><p><b>CONCLUSION</b>Chromosomal changes were detected in four cases of infantile autism, with a detectability of 5.9% , far lower than that (10% to 48%) reported in literature. The breakpoint of translocation could be detected more accurately using BAC FISH method.</p>