Exonuclease combinations reduce noises in 3D genomics technologies.

Chromosome conformation-capture technologies are widely used in 3D genomics; however, experimentally, such methods have high-noise limitations and, therefore, require significant bioinformatics efforts to extract reliable distal interactions. Miscellaneous undesired linear DNAs, present during proximity-ligation, represent a main noise source, which needs to be minimized or eliminated. In this study, different exonuclease combinations were tested to remove linear DNA fragments from a circularized DNA preparation. This method efficiently removed linear DNAs, raised the proportion of annulation and increased the valid-pairs ratio from ∼40% to ∼80% for enhanced interaction detection in standard Hi-C. This strategy is applicable for development of various 3D genomics technologies, or optimization of Hi-C sequencing efficiency.

[Effects of serums containing Buzhong Yiqi decoction with Astragalus Radix or Hedysari Radix on anti-immunosenescence in spleen lymphocytes of SAMP8 mice].

This paper was aimed to compare the effect of Buzhong Yiqi decoction containing Hedysari Radix or Astragali Radix on anti-immunosenescence effects in spleen lymphocytes of senescence accelerated mouse 8 (SAMP8). The effect of the serums on the proliferation of spleen T lymphocytes in SAMP8 mice induced by ConA was tested by MTT. The effect of the serums on the T lymphocytes subsets of SAMP8 mice was measured by flow cytometry. ELISA was used to detect the level of IL-2 and IFN-γ in the culture supernatants of spleen lymphocytes. The effect of the serums on the expression of CD28 mRNA in spleen T lymphocytes was detected by fluorescent quantitative PCR. Western blot was used to detect the expression of CD28 protein in spleen T lymphocytes of SAMP8 mice. Both the serums of Buzhong Yiqi decoctions containing Hedysari Radix or Astragali Radix improved the proliferation of T lymphocytes in SAMP8 mice. Both the serums had no obvious effect on the differentiation of spleen T lymphocytes'subsets in SAMP8 mice. Both the serums increased the content of IL-2 and INF-γ in the culture supernatants of spleen lymphocytes. And for the content of IL-2, the serum of Buzhong Yiqi decoction with Hedysari Radix was better（P<0.05）. Both the serums improved the expression of CD28 mRNA in spleen T lymphocytes of SAMP8 mice. And the effect of Hedysari Radix group was better than that of Astragalus Radix group（P<0.05）. Both the serums improved the expression of CD28 protein in spleen T lymphocytes of SAMP8 mice. The role of the serums containing Buzhong Yiqi decoction with Astragalus Radix and the decoction with Hedysari Radix in anti-immunosenescence was through the effect of the CD28. And the effect of Hedysari Radix group was better than that of Astragalus Radix group on improved the expression of CD28 mRNA in T lymphocytes of SAMP8 mice. Astragalus Radix and Hedysari Radix could swap in the aspect of anti-immunosenescence.