1.Research progress in the relationship between loss of heterozygosity events and antifungal drug resistance in Candida albicans
Rongchen DAI ; Xin FAN ; Canran JIANG ; Jie GONG ; Meng XIAO ; Conghua JI
Chinese Journal of Microbiology and Immunology 2023;43(4):309-315
Candida albicans as a pathogen of great clinical significance can widely colonize in many ecological niches of human body, especially in the immunocompromised population. Currently, antifungal drugs that can be used in clinical treatment are very limited. However, the genome of Candida albicans has a high rate of mutation, which can help it quickly develop resistance to antifungal drugs. Therefore, drug resistance in Candida albicans remains a great threat to clinical practice. This article focused on the frequent loss of heterozygosity (LOH) events in Candida albicans, summarized the association between LOH and other genomic variants and discussed the relationship of the frequency of de novo mutations, heterozygous status of key drug resistance genes and reproductive pattern with antifungal drug resistance.
2.Analysis of genomic copy number variations in two sisters with primary amenorrhea and hyperandrogenism.
Yanliang ZHANG ; Qiuyue XU ; Xuemei CAI ; Yixun LI ; Guibo SONG ; Juan WANG ; Rongchen ZHANG ; Yong DAI ; Yong DUAN
Chinese Journal of Medical Genetics 2015;32(6):814-818
OBJECTIVETo analyze genomic copy number variations (CNVs) in two sisters with primary amenorrhea and hyperandrogenism.
METHODSG-banding was performed for karyotype analysis. The whole genome of the two sisters were scanned and analyzed by array-based comparative genomic hybridization (array-CGH). The results were confirmed with real-time quantitative PCR (RT-qPCR).
RESULTSNo abnormality was found by conventional G-banded chromosome analysis. Array-CGH has identified 11 identical CNVs from the sisters which, however, overlapped with CNVs reported by the Database of Genomic Variants (http://projects.tcag.ca/variation/). Therefore, they are likely to be benign. In addition, a -8.44 Mb 9p11.1-p13.1 duplication (38,561,587-47,002,387 bp, hg18) and a -80.9 kb 4q13.2 deletion (70,183,990-70,264,889 bp, hg18) were also detected in the elder and younger sister, respectively. The relationship between such CNVs and primary amenorrhea and hyperandrogenism was however uncertain. RT-qPCR results were in accordance with array-CGH.
CONCLUSIONTwo CNVs were detected in two sisters by array-CGH, for which further studies are needed to clarify their correlation with primary amenorrhea and hyperandrogenism.
Amenorrhea ; diagnosis ; genetics ; Chromosomes, Human, Pair 4 ; genetics ; Chromosomes, Human, Pair 9 ; genetics ; Comparative Genomic Hybridization ; methods ; DNA Copy Number Variations ; genetics ; Female ; Humans ; Hyperandrogenism ; diagnosis ; genetics ; Karyotyping ; Reverse Transcriptase Polymerase Chain Reaction ; Siblings ; Young Adult
3.Evaluation of chemiluminescence immunoassay kit for detection of hepatitis D virus IgG antibody
Rongchen YUAN ; Fangming CHENG ; Kuanhui XIANG ; Yongcong LI ; Tianxun HUANG ; Zhenchao TIAN ; Xiongwei LIU ; Xiaozhong WANG ; Zhuanguo WANG ; Yahong MA ; Jing ZHOU ; Erhei DAI ; Chungen QIAN ; Tong LI ; Tao SHEN ; Bangning CHENG
Chinese Journal of Laboratory Medicine 2024;47(3):234-238
Objective:This study evaluates the performance of chemiluminescence assay, which is designed to detect Hepatitis D Virus (HDV) Immunoglobulin G (IgG) antibodies.Methods:A comparative analysis was conducted among chemiluminescence anti-HDV IgG reagent, the magnetic particle-based domestic reagent A and domestic reagent B, and the Robo Gene HDV RNA kit, using 1909 HBsAg-positive plasma samples. This comparison aimed to delineate clinical specificity and detection accuracy. The anti-HDV IgG reagent precision was assessed at three different concentration levels following the Clinical Laboratory Standards Institute EP5-A2 guidelines. The specificity of the assay was validated using 200 HAV IgM positive, 545 HBsAg-positive but anti-HDV IgG-negative, 350 anti HCV positive plasma samples and 200 healthy human blood samples. Additionally, a concordance study was conducted with 545 HBsAg-positive and 37 anti-HDV IgG-positive plasma samples, comparing the anti-HDV IgG reagent against reagent A.Results:1 909 HBsAg-positive plasma samples were tested using 3 anti HDV IgG reagent and 1 HDV RNA reagent, 19 samples were identified as anti-HDV IgG-positive. The anti-HDV IgG demonstrated superior accuracy and specificity. The assay exhibited excellent precision, with intra-assay coefficient of variation (CV) values ranging from 1.57% to 4.30%, and inter-assay CV values between 1.71% and 4.67% for detecting samples at high, medium, and low concentration levels. Concordance with Reagent A showed consistent results in both positive and negative detections.Conclusion:In this study, the anti-HDV IgG reagent (chemiluminescence method) displayed outstanding specificity in detecting clinical samples and exhibited a high conformity rate with commercialized reagents, making it potentially suitable for screening anti-HDV IgG in HBsAg-positive samples.
4.Assessment and preliminary clinical application of a domestic nucleic acid detection reagent for hepatitis D virus
Yongcong LI ; Rongchen YUAN ; Kuanhui XIANG ; Guomin OU ; Tianxun HUANG ; Fangming CHENG ; Zhenchao TIAN ; Xiongwei LIU ; Xiaozhong WANG ; Feng GUO ; Yahong MA ; Jing ZHOU ; Erhei DAI ; Bangning CHENG ; Tong LI ; Tao SHEN ; Chungen QIAN
Chinese Journal of Laboratory Medicine 2024;47(3):239-244
Objective:This study aims to evaluate the quality and explore the preliminary clinical applications of a domestically developed hepatitis D virus nucleic acid quantification reagent (abbreviated as"domestic HDV RNA reagent").Methods:The sensitivity and accuracy of the reagent were evaluated in accordance with the WHO HDV RNA international standard, employing the Bio-Rad CFX Opus 96 real-time fluorescence quantitative PCR analysis system. Serial dilutions of pseudo-viruses or cell culture-derived virus were used to determine the linear range of the domestic HDV RNA reagent. Specificity was assessed using positive samples of HAV, HBV, HCV infection, and HEV national reference materials. Precision was evaluated with samples at both high and low concentrations. In a comparative analysis, 30 HDV IgG positive samples were tested using both the domestic HDV RNA reagent and the RoboGene HDV RNA kit based on the ABI 7500 FAST DX system. The Pearson correlation coefficient (r) was used to examine the correlation between the two reagents.Results:The domestic HDV RNA reagent demonstrated a high sensitivity of up to 6 IU/ml, consistent with that of the comparator reagent. The calibration curve for WHO HDV RNA standards had a slope of -3.286, with an amplification efficiency of 101.6%. The linear detection range spanned from 10 to 10 8 IU/ml for eight HDV genotypes. The domestic HDV RNA reagent exhibited exceptional specificity, without cross-reactivity observed with HAV, HBV, HCV, or HEV. Accuracy assessments at five concentration levels met the required standards, with intra-assay precision coefficient of variation ( CV) ranging from 1.20% to 4.20%, and inter-assay precision CV from 1.20% to 7.90%. The detection results for HDV IgG positive samples were highly correlated with the comparator reagent ( r=0.984, P<0.001), achieving a diagnostic accuracy of 100% compared to sequencing results. Conclusion:In this study, the domestic HDV RNA reagent possesses excellent specificity, accuracy, precision, and a broad linear range, attaining a sensitivity level on par with international reagents of the same type.