Archives

  • 2018-07
  • 2018-10
  • 2018-11
  • 2019-04
  • 2019-05
  • 2019-06
  • 2019-07
  • 2019-08
  • 2019-09
  • 2019-10
  • 2019-11
  • 2019-12
  • 2020-01
  • 2020-02
  • 2020-03
  • 2020-04
  • 2020-05
  • 2020-06
  • 2020-07
  • 2020-08
  • 2020-09
  • 2020-10
  • 2020-11
  • 2020-12
  • 2021-01
  • 2021-02
  • 2021-03
  • 2021-04
  • 2021-05
  • 2021-06
  • 2021-07
  • 2021-08
  • 2021-09
  • 2021-10
  • 2021-11
  • 2021-12
  • 2022-01
  • 2022-02
  • 2022-03
  • 2022-04
  • 2022-05
  • 2022-06
  • 2022-07
  • 2022-08
  • 2022-09
  • 2022-10
  • 2022-11
  • 2022-12
  • 2023-01
  • 2023-02
  • 2023-03
  • 2023-04
  • 2023-05
  • 2023-06
  • 2023-07
  • 2023-08
  • 2023-09
  • 2023-10
  • 2023-11
  • 2023-12
  • 2024-01
  • 2024-02
  • 2024-03
  • Then we explored the MCLEIA

    2019-07-18

    Then, we explored the MCLEIA methodology parameters including precision, accuracy and specificity. In the 0.5–128 ng/mL, the standard curve equation was  = 0.5014 + 1.769 ( was log, was RLU/RLU with a correlation coefficient of 0.9907) (). On the one hand, same sample (0.5, 4.0, 32.0 ng/mL) detected six times to value the inter-assay precision. To value the intra-assay precision, comparing data from two microplates. The RSD of intra- and inter-assays were 15.8%–16.9% and 14.3%–18.1%, respectively. The recoveries of the method were 70%–106.2% (). Because of the complexity of the components in serum sample, the established MCLEIA method is required to have high specificity for DNMT1. Therefore, DNMT3A and DNMT3B with similar structure were selected. Their cross-reactivity rates were 0.31% and 0.34%, respectively. The low cross-reaction rate indicated that McAb had no specific reaction to other DNMTs. Therefore, the established MCLEIA method had good specificity and could be used to detect DNMT1 in samples. Although there are several ways to detect DNMT1 concentration, the only commercial kits are ELISA. Thus, the results obtained using the proposed MCLEIA in the quantity of DNMT1 in serum samples were compared with the commercial ELISA kit. The correlation between the two groups of data was analyzed. The results showed that there was a good correlation between the two groups (correlation coefficient  = 0.9889,  <  0.01) (). The result suggests that the MCLEIA displays stable performance for determination of DNMT1 and is appropriate for high-throughput detection in clinical diagnosis. In summary, a simple, sensitive and selective enhanced chemiluminescence system was composed of HRP, luminal, HO and BIP was developed for the detection of DNMT1. The proposed MCLEIA method was finally applied to determine DNMT1 in 36 samples of lung cancer serum. Results obtained using the method showed high correlation with the purchasable ELISA kit. Thus, the MCLEIA established in this apexbt chemicals study could be used for the sensitive quantitative detection of DNMT1 in serum and presented a promising application potential. Acknowledgments This work was supported by the National Natural Science Foundation of China (Nos. 81402721, 81573203, 21605131) and Science and Technology Department of Henan Province (No. 22170004).
    Introduction DNA methylation is one of the epigenetic marks and plays critical roles in transcriptional activation or repression of development-related genes, genomic imprinting and X-chromosome inactivation (Jones, Liang, 2009, Kaneda et al, 2004). Mammals have two copies of every gene, and both maternal and paternal genes have the same function so only one of the parental alleles must be expressed. Control of this expression is known as genomic imprinting (Barlow and Bartolomei, 2014). In this process, DNA methylation plays an important role in the repression or activation of imprinting genes such as H19 (Bartolomei et al., 1993) and IGF2 (Stoger et al., 1993). In X-chromosome inactivation, a widespread DNA methylation at cytosine-phosphate-guanine (CpG) sites occurs to inactivate one of the X-chromosomes in females (Heard et al., 1997), and DNA methylation provides maintenance of the inactivation during the lifespan of female cells (Hansen et al., 1996). In DNA methylation, a methyl group is added to the fifth carbon atom of the cytosine residues using S-adenosyl-l-methionine (SAM) as a methyl donor (Chen, Li, 2004, Portela, Esteller, 2010). DNA methylation generally occurs in CpG dinucleotide sites, but rarely appears in non-CpG sites such as cytosine-phosphate-thymine (CpT), cytosine-phosphate-adenine (CpA) and cytosine-phosphate-cytosine (CpC) (Chen, Li, 2004, Reik, Dean, 2001) except for CpA islands which are highly methylated in embryonic stem cells (Ramsahoye et al., 2000). To date, two different DNA methylation mechanisms have been identified: de novo and maintenance. While maintenance methylation primarily functions in maintaining the previously methylated genomic sites during DNA replication, the de novo methylation process creates new marks on DNA. Moreover, de apexbt chemicals novo methylation plays crucial roles in re-establishing genomic imprints following global DNA demethylation in germ cells (Law and Jacobsen, 2010). In both mechanisms, DNA methylation is catalysed by specific DNA methyltransferase (DNMT) enzymes. To date, five structurally distinct DNMT have been characterized: DNMT1, DNMT2, DNMT3A, DNMT3B and DNMT3L (Bestor, 2000).