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Background: The aim of the study was to obtain stable radioresistant sub-lines from the human cervical cancer cell line HeLa by prolonged exposure to 252Cf neutron and X-rays. Radioresistance mechanisms were investigated in the resulting cells using microarray analysis of DNA damage repair genes.Methods: HeLa cells were treated with fractionated 252Cf neutron and X-rays, with a cumulative dose of 75 Gy each, over 8 months, yielding the sub-lines HeLaNR and HeLaXR. Radioresistant characteristics were detected by clone formation assay, ultrastructural observations, cell doubling time, cell cycle distribution, and apoptosis assay. Gene expression patterns of the radioresistant sub-lines were studied through microarray analysis and verified by Western blotting and real-time PCR.Results: The radioresistant sub-lines HeLaNR and HeLaXR were more radioresisitant to 252Cf neutron and X-rays than parental HeLa cells by detecting their radioresistant characteristics, respectively. Compared to HeLa cells, the expression of 24 genes was significantly altered by at least 2-fold in HeLaNR cells. Of these, 19 genes were up-regulated and 5 down-regulated. In HeLaXR cells, 41 genes were significantly altered by at least 2-fold; 38 genes were up-regulated and 3 down-regulated.Conclusions: Chronic exposure of cells to ionizing radiation induces adaptive responses that enhance tolerance of ionizing radiation and allow investigations of cellular radioresistance mechanisms. The insights gained into the molecular mechanisms activated by these "radioresistance" genes will lead to new therapeutic targets for cervical cancer. [ABSTRACT FROM AUTHOR]

While studying caesarean decision-making in China, the increasing popularity of 'zuoyuezi' emerged. This paper addresses this development, the reasons and implications.We tape-recorded semi-structured interviews in three industrial cities in China. The three groups of informants comprised women in the first-week after caesarean, women eight months after caesarean and health-workers/others. Mandarin or local dialects were used.The data were transcribed and analysed in Chinese and then selected quotes were translated into English.We found that the re-emergence and social modification of zuoyuezi is closely associated with the rising caesarean rate. This custom has been regarded as a crucial rite-of-passage for the woman's recovery and transition to motherhood after childbirth. Its particular importance after caesarean became apparent in this study. Conclusions are drawn about the place of ritual and tradition in 21st century China. [ABSTRACT FROM AUTHOR]