Research progress of MSI-CRC on anti-PD-1 therapy / 国际外科学杂志

The programmed cell death receptor 1 (PD-1) antibody has been used in the treatment of a variety of malignant tumors, in which colorectal cancer is considered immune " cold" tumor and is not sensitive to anti-PD-1 therapy. The molecular characteristics of mismatch repair deficient (dMMR)/high microsatellite instability (MSI-H) are important molecular markers for screening patients with immune checkpoint inhibitors therapy (ICIs). However, only some patients can benefit from ICIs treatment, and some patients even have disease progression. This article summarizes the research progress of anti-PD-1 immunotherapy of MSI-CRC in recent years, including the mechanisms of resistance, new efficacy biomarkers and treatment options, so as to provide ideas for expanding the application of immunotherapy in colorectal cancer.

Determination of perchlorate in food by ultra performance liquid chromatography-tandem mass spectrometry / 中国食品卫生杂志

Objective To establish a method for the determination of perchlorate in food by ultra performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS).Methods The perchlorate residue in spices and condiments was extracted with water,that in vegetables and fruits was extracted with acetonitrile-water (1∶ 1,V/V),and that in meat,poultry,eggs,milk and aquatic products was extracted with acetonitrile-water (2∶ 1,V/V).The supernatant was cleaned up with C18 SPE (3 ml,200 mg),and the detection was carried out by UPLC-MS/MS with internal standardmethod for quantification.Results The calibration curve was linear in the concentration range of 0.3-20.0 pg/L (R2 ≥0.999),the recovery was in the range of 82.6％-108.6％,the relative standard deviation (RSD) was in the range of 1.0％-9.9％,and the limit of detection was 2.0 μg/kg for milk,and 10.0 μg/kg for other food.Conclusion The method was simple,accurate and highly sensitive,and suitable for the determination of perchlorate in food.

Non-invasive prenatal test in 2 949 intermediate risk women after traditional Down syndrome screening / 天津医药

Objective To explore the value of non-invasive prenatal test (NIPT) in pregnant women with intermediate risk after traditional Down syndrome screening. Methods From March 1 2015 to March 31 2016, a total of 2 949 pregnant women with intermediate risk after traditional Down syndrome screening who received NIPT as the second-line screening method at Shenzhen Maternity and Child Healthcare Hospital after informed consent were recruited for this study. Retrospective data analysis including the results of traditional Down syndrome screening, ultrasound, NIPT and invasive amniocentesis to fetal karyotype analysis were conducted, and pregnant outcomes were followed up. Results NIPT results were all obtained in 2 949 pregnant women with intermediate risk after traditional Down syndrome screening. Of 25 NIPT-positive cases, 24 cases received invasive amniocentesis to fetal karyotype analysis. Thirteen cases were confirmed with fetal chromosomal abnormalities including 5 cases of trisomy 21, 2 cases of trisomy 13, 4 cases of sex chromosomal abnormalities and 2 cases of other chromosomal abnormalities. In addition, 1 NIPT-positive case refused prenatal diagnosis was confirmed normal result after birth. The postnatal follow-up in NIPT-negative women did not find any newborn with chromosomal abnormality. The incidence of fetal chromosomal abnormalities in women with intermediate risk was 0.44% (13/2 949). Conclusion NIPT can be used as second-line screening method in pregnant women with intermediate risk after Down syndrome screening, which could lead to the prenatal detection of a higher proportion of fetal chromosomal abnormalities and a lower invasive-testing rate.

Differential expression and function of chitinase 3-like-1 in macrophage stimulated by Sporothrix schenckii / 中国人兽共患病学报

We evaluated the differential expression and function of chitinase 3‐like‐1 in macrophage stimulated by Sporothrix schenckii and Candida albicans fungicidal ability of macrophage after stimulation with Sporothrix schenckii and Candida albi‐cans separately was detected .The expression of CHI3L1 gene in macrophage stimulated by Sporothrix Schenckii and Candida albicans was evaluated with real‐time PCR .The function of CHI3L1 protein in macrophages against the reproduction of Sporo‐thrix schenckii and Candida albicans was detected in vitro .Results showed that macrophages could engulf and kill Sporothrix Schenckii and Candida albicans in vitro .The expression of CHI3L1 gene in macrophage stimulated by Candida albicans was increased obviously .At the same time ,CHI3L1 protein can damper the reproduction of Candida albicans .However ,the ex‐pression of CHI3L1 gene was not elevated when macrophage was stimulated by Sporothrix schenckii and CHI3L1 protein played little role in reproduction of Sporothrix schenckii .The expression of CHI3L1 gene in macrophage was elevated after stimulation with Candida albicans ,but was not elevated with Sporothrix Schenckii .In correspondence with differential ex‐pression ,CHI3L1 in macrophages could impair the reproduction of Candida albicans but had a weak function on Sporothrix schenckii which might contribute to the pathogenesis of spo‐rotricosis .

Cloning and expression of cyclophilin A gene from Echinoccocus granulosus / 中华检验医学杂志

Objective In order to assess the value of Echinoccocus granulosus cyclophilin A (EgypA) in immune diagnosis,this novel gene was cloned and expressed.Methods By screening the EST library,the coding region of EgCypA was identified,and the PCR primers were designed based on this sequence.Bioinformatic tools were used to deduce the amino acid sequence of EgCypA and analyzed its biological characteristics.EgCypA was amplified from E.granulosus cDNA library by using PCR.Then,it was cloned into the prokaryotic expression vector pET28a and transformed into E.coli BL21.The recombinant protein was expressed in E.coli BL21 after IPTG induction.The immunogenicity of EgCypA was evaluated by Western blot using the Echinoccocus granulosus and other parasites infected animals' sera.Results Results of SDS-PAGE electrophoresis show that the recombinant BL21 expressed 18 400-25 000 protein,which was identical with the molecular weight calculated by bioinformatic analysis.Western blot shows that the recombinant protein only reacted with its immune serum and E.granulosus cystic fluid immune serum,and EgCypA immune serum could react with the excretion and secretion antigen from E.granulosus protoscolexes,and no cross-reaction between EgCypA and sera from other parasites infected animals.Conclusions Cloning and expression of EgCypA are successful.EgCypA has good immunologic activity and could be a candidate molecular for immune diagnosis of echinococcosis in early stage.