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Effects of DNA damage on oocyte meiotic maturation and early embryonic development

Shen YIN,Junyu MA,Wei SHEN

《农业科学与工程前沿（英文）》 2014年第1卷第3期页码 185-190 doi: 10.15302/J-FASE-2014035

摘要： DNA damage is one of the most common threats to meiotic cells. It has the potential to induce infertility and genetic abnormalities that may be passed to the embryo. Here, we reviewed exogenous factors which could induce DNA damage. Specially, we addressed the different effects of DNA damage on mouse oocytes and embryonic development. Complex DNA damage, double-strand breaks, represents a more difficult repair process and involves various repair pathways. Understanding the mechanisms involved in DNA damage responses may improve therapeutic strategies for ovarian cancer and fertility preservation.

关键词： DNA damage double-strand breaks (DSBs) oocyte embryo

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Development of the expressed immunoglobulin μ chain repertoire during maturation of mice B cells

Jingwen LIANG,Yingfeng LUO,Yi SUN,Meng LEI,Bing ZHANG,Songnian HU,Yaofeng ZHAO

《农业科学与工程前沿（英文）》 2014年第1卷第3期页码 201-213 doi: 10.15302/J-FASE-2014017

摘要： In the bone marrow and spleen, the developing B cell populations undergo both negative and positive selections to shape their B cell receptor repertoire. To gain insight into the shift of the immunoglobulin heavy (IgH) chain repertoire during B cell development, we undertook large scale Ig μ chain repertoire analysis of pre-B, immature B and spleen B cell populations. We found that the majority of V gene segments, V families, J and D gene segments, were observed to have significantly different usage frequencies when three B cell populations were compared, but the usage profile of the V D, and J genes between different B cell populations showed high correlations. In both productive and nonproductive rearrangements, the length of CDRH3 shortened significantly on average when B cells entered the periphery. However, the CDRH3 length distribution of nonproductive rearrangements did not follow a Gaussian distribution, but decreased successively in the order 3 -2, 3 -1 and 3 , suggesting a direct correlation between mRNA stability and CDRH3 length patterns of nonproductive rearrangements. Further analysis of the individual components comprising CDRH3 of productive rearrangements indicated that the decrease in CDRH3 length was largely due to the reduction of N addition at the 5′ and 3′ junctions. Moreover, with development, the amino acid content of CDRH3 progressed toward fewer positively charged and nonpolar residues but more polar residues. All these data indicated that the expressed Ig μ chain repertoire, especially the repertoire of CDRH3, was fine-tuned when B cells passed through several checkpoints of selection during the process of maturation.

关键词： repertoire complementarity determining region 3 of the IgH chain (CDRH3) immunoglobulin heavy chain variable region

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Reduction of rough set attribute based on immune clone selection

LIANG Lin, XU Guang-hua

《机械工程前沿（英文）》 2006年第1卷第4期页码 413-417 doi: 10.1007/s11465-006-0049-4

摘要： A novel attribute reduction approach of rough set based on immune clone selection is proposed. In this method, the approximation quality and attribute set were adopted as evolution object and antibody, respectively. On the basis of the inherent distribution within the immune response, the global optimization of the antibody was realized through parallel local optimization. Moreover, the diversity of the antibody population was maintained with the affinity maturation and renewal of the antibody. Thus, the stable multi-optimal solutions can be preserved. In addition, the machinery fault data were analyzed by this method, and the attribute reduction sets were obtained further to satisfy the demand of feature selection in machinery diagnosis.

关键词： inherent distribution maturation evolution diversity antibody