OBJECTIVE: To assess the value of non-invasive prenatal testing (NIPT) for detecting fetal chromosomal microdeletion/microduplication syndromes by carrying out prenatal diagnoses for two fetuses with Xp22.31 microdeletion indicated by NIPT. METHODS: Two pregnant women suspected for fetal Xp22.31 microdeletion syndrome who presented at Zaozhuang Maternal and Child Health Care Hospital on December 5, 2017 and October 15, 2020 were selected as the study subjects. Clinical data of the two women were collected, and peripheral venous blood samples were collected for NIPT testing. Amniotic fluid samples were taken for G-banding chromosomal karyotyping analysis and copy number variation sequencing (CNV-seq) for fetus 1, while G-banding chromosomal karyotyping and single nucleotide polymorphism microarray analysis (SNP array) were carried out for fetus 2. Peripheral venous blood samples of couple 1 were collected for CNV-seq to verify the origin of copy number variation . RESULTS: NIPT indicated that fetus 1 had harbored a 1.3 Mb deletion in the Xp22.31 region, while G-banding chromosomal karyotyping had found no abnormality. CNV-seq analysis verified the fetus to be seg[GRCh37]del(X)(p22.31)chrX:g.6800001_7940000del, with a 1.14 Mb deletion at Xp22.31, which was derived from its mother. NIPT indicated that fetus 2 had harbored a 1.54 Mb deletion in the Xp22.31 region, while G-banding chromosomal karyotyping had found no abnormality. SNP array analysis indicated arr[GRCh37]Xp22.31(6458940_8003247)×0, with a 1.54 Mb deletion in Xp22.31 region. CONCLUSION NIPT not only has a good performance for detecting fetal trisomies 21, 18 and 13, but also has the potential for detecting chromosomal microdeletion/microduplications. For high risk fetuses indicated by NIPT, prenatal diagnosis needs to be carry out to verify the chromosomal abnormalities.
Child ; Female ; Pregnancy ; Humans ; DNA Copy Number Variations ; Prenatal Diagnosis ; Down Syndrome/diagnosis* ; Chromosome Aberrations ; Fetus

Objective To screen and identify the in vivo-induced antigen Tp0462 of Treponema pallidum (Tp),and to evaluate its value for clinical serological diagnosis of syphilis.Methods Genomewide DNA was extracted from the Tp Nichols strain,and polymerase chain reaction (PCR) was performed to amplify the Tp0462 gene.A recombinant plasmid pET30a (+)-Tp0462 was constructed and transfected into the Escherichia coli (E.coli) Rosetta (DE3) strain.Recombinant protein Tp0462 was abundantly expressed,purified and identified.A total of 18 New Zealand rabbits were randomly and equally divided into 3 groups:viable Tp-incubating group incubated with viable Tp in the testes,inactived Tp-incubating group incubated with ultraviolet irradiation-killed Tp in the testes,and control group receiving no treatment.After incubation,blood samples were collected at different time points,and the sera were isolated for identification of characteristics of in vivo-induced antigen Tp0462.Enzyme-linked immunosorbent assay for Tp0462 (Tp0462-ELISA),Treponema pallidum particle agglutination assay (TPPA),preliminary syphilis screening ELISA and rapid plasma reagin (RPR) card test were applied in 336 clinical serum samples from patients with syphilis,so as to preliminarily evaluate the value of Tp0462 for the diagnosis of syphilis.Results The optimum conditions for expression of the recombinant plasmid Tp0462-pET30a(+) in E.coli Rosetta (DE3) strains were the treatment with 0.5 mmol/L isopropyl thiogalactoside (IPTG) on a shaker at 180 rpm for 4 hours.In the viable Tp-incubating group,the serum level of specific anti-Tp0462 antibody sharply increased from week 2,and went steady after week 5.However,the specific anti-Tp0462 antibody maintained a low level in the inactived Tp-incubating group and the control group.The viable Tp-incubating group showed a significantly higher level of specific anti-Tp0462 antibody compared with the inactived Tp-incubating group and the control group (both P ＜ 0.05),while no significant difference was observed between the inactived Tp-incubating group and the control group (P =0.256).The level of anti-Tp92 antibody was significantly higher in the viable Tp-incubating group and the inactived Tp-incubating group than in the control group (P ＜ 0.05),while there was no significant difference between the viable Tp-incubating group and the inactived Tp-incubating group (P =0.127).Compared with TPPA,the sensitivity,specificity,consistency rate and area under the curve (AUC) of Tp0462-ELISA for the diagnosis of syphilis were 91.7％,98.8％,95.2％ and 0.997 respectively.Tp0462-ELISA was consistent to preliminary syphilis screening ELISA and RPR with a Kappa coefficient of 0.846 and 0.293,respectively.Conclusion Tp0462-ELISA has shown evidently higher sensitivity and specificity in the serodiagnosis of syphilis,and Tp0462 can serve as promising antigens for the diagnosis of syphilis.

OBJECTIVE: To assess the value of non-invasive prenatal testing (NIPT) for trisomy 21 (T21), trisomy 18 (T18), trisomy 13 (T13), sex chromosome aneuploidies, chromosomal microdeletions and microduplications using cell-free fetal DNA from peripheral blood samples of pregnant women. METHODS: A total of 15 237 pregnant women who had undergone NIPT testing at the Maternity and Child Health Care Hospital of Zaozhuang from February 2015 to December 2021 were enrolled in this study. For those with a high risk by NIPT, amniotic fluid samples were collected for G-banding chromosomal karyotyping analysis and chromosomal microarray analysis to verify the consistency of NIPT with results of prenatal diagnosis. All of the women were followed up by telephone for pregnancy outcomes. RESULTS: Among the 15 237 pregnant women, 266 (1.75%) were detected with a high risk for fetal chromosomal abnormality were detected. Among these, 79 (29.7%) were at a high risk for T21, 26 (9.77%) were at a high risk for T18, 9 (3.38%) were at a high risk for T13, 74 (27.82%) were at a high risk for sex chromosome aneuploidies, 12 (4.51%) were at a high risk for other autosomal aneuploidies, and 66 (24.81%) were at a high risk for chromosomal microdeletions or microduplications. 217 women had accepted invasive prenatal diagnosis and respectively 50, 13, 1, 25, 1 and 18 were confirmed with T21, T18, T13, sex chromosome aneuploidies, autosomal aneuploidies and microdeletions/microduplications, and the positive predictive values were 75.76%, 68.42%, 11.11%, 40.32%, 10% and 35.29%, respectively. For 13 042 women (85.59%), the outcome of pregnancy were successfully followed up. During the follow-up, one false negative case of T21 was discovered. No false positive cases for T13 and T18 were found. CONCLUSION NIPT has a sound performance for screening T13, T18 and T21, and is also valuable for screening other autosomal aneuploidies, sex chromosome aneuploidies and chromosomal microdeletions/microduplications.
Child ; Female ; Pregnancy ; Humans ; Retrospective Studies ; Cell-Free Nucleic Acids ; Chromosome Disorders/genetics* ; Prenatal Diagnosis/methods* ; Down Syndrome/genetics* ; Sex Chromosome Aberrations ; Trisomy 18 Syndrome/genetics* ; Trisomy 13 Syndrome/diagnosis* ; Aneuploidy ; DNA/genetics* ; Trisomy/genetics*