A paradigm shift in noninvasive prenatal screening has been made with the discovery of cell-free fetal DNA in maternal plasma. Noninvasive prenatal screening is primarily used to screen for fetal aneuploidies, and has been used globally. Fetal fraction, an important parameter in the analysis of noninvasive prenatal screening results, is the proportion of fetal cell-free DNA present in the total maternal plasma cell-free DNA. It combines biological factors and bioinformatics algorithms to interpret noninvasive prenatal screening results and is an integral part of quality control. Maternal and fetal factors may influence fetal fraction. To date, there is no broad consensus on the factors that affect fetal fraction. There are many different approaches to evaluate this parameter, each with its advantages and disadvantages. Different fetal fraction calculation methods may be used in different testing platforms or laboratories. This review includes numerous publications that focused on the understanding of the significance, influencing factors, and interpretation of fetal fraction to provide a deeper understanding of this parameter.
Objective. To assess the clinical value of prenatal diagnosis using quantitative fluorescent polymerase chain reaction (QF-PCR) and chromosomal microarray analysis (CMA) for the examination of genomic imbalances in prenatal amniotic fluid samples from fetuses with a nuchal translucency (NT) greater than or equal to 2.5 mm. Materials and Methods. A total of 494 amniotic fluid samples and 5 chorionic villus samples were included in this study, with a fetal NT ≥ 2.5 mm at 11–13+6 weeks of gestation from November 2015 to December 2018. All cases were examined with QF-PCR, and those with normal QF-PCR results were then analyzed by CMA. Results. Of the 499 cases, common aneuploidies were detected by QF-PCR in 61 (12.2%) cases. One case of triploidy, one case of trisomy 21 mosaicism, and two cases of X/XX mosaicism were further confirmed by fluorescence in situ hybridization (FISH). Among the 434 cases with normal QF-PCR results, microarray detected additional pathogenic copy number variants (CNVs) in 4.8% (21/434) of cases. Six cases would have been expected to be detectable by conventional karyotyping because of large deletions/duplications (>10 Mb), leaving fifteen (3.5%, 15/428) cases with pathogenic CNVs only detectable by CMA. Pathogenic CNVs, especially those <10 Mb, were centralized in cases with an NT < 4.5 mm, including 5 pathogenic CNVs in cases with an NT of 2.5–3.5 mm and 7 pathogenic CNVs in cases with an NT of 3.5–4.5 mm. Conclusions. It is rational to use a diagnostic strategy in which CMA is preceded by a less-expensive, rapid method, namely, QF-PCR, to detect common aneuploidies. CMA allows for the detection of a number of pathogenic chromosomal aberrations in fetuses with an NT ≥ 2.5 mm.
Background: Ubiquitination is a reversible process of posttranslational protein modification through the action of the family of deubiquitylating enzymes which contain ubiquitin-specific protease 9x (USP9X). Recent evidence indicates that USP9X is involved in the progression of various human cancers. The aim was to detect the expression of USP9X in the progression from normal epithelium to invasive esophageal squamous cell cancer (ESCC) and evaluate the relevance of USP9X expression to the tumor progression and prognosis.Methods: In this study, USP9X immunohistochemical analysis was performed on tissues constructed from ESCC combined with either normal epithelium or adjacent precursor tissues of 102 patients. All analyses were performed by SPSS 13.0 software.Results: We observed that the level of high USP9X expression increased gradually in the transformation from normal epithelium (4.0%), to low grade intraepithelial neoplasia (10.5%), then to high grade intraepithelial neoplasia (28.6%), and finally to invasive ESCC (40.2%). The expression of USP9X was found to be significantly different between the normal mucosa and ESCC (P < 0.001), and between low grade intraepithelial neoplasia and high grade intraepithelial neoplasia (p = 0.012). However, no difference was observed between the high expression of USP9X in normal mucosa and low grade intraepithelial neoplasia (P = 0.369), nor between high grade intraepithelial neoplasia and ESCC (p = 0.115). Interestingly, the most intensive staining for USP9X was usually observed in the basal and lower spinous layers of the esophageal epithelium with precursor lesions which often resulted in the earliest malignant lesion. USP9X expression status was positively associated with both depth of invasion (p = 0.046) and lymph node metastasis (p = 0.032). Increased USP9X expression was significantly correlated to poorer survival rate in ESCC patients (p = 0.001). When adjusted by multivariate analysis, USP9X expression (HR 2.066, P = 0.005), together with TNM stage (HR 1.702, P = 0.042) was an independent predictor for overall survival.Conclusions: Up-regulation of USP9X plays an important role in formation and progression of precancerous lesions in ESCC and USP9X expression levels were significantly correlated with the survival of ESCC patients. Thus, USP9X could be considered as a potential biomarker and prognostic predictor for ESCC.Virtual slides: The virtual slides for this article can be found here:http://www.diagnosticpathology.diagnomx.eu/vs/1945302932102737
Vulvovaginal candidiasis (VVC) is a common vaginitis caused by Candida species,a frequently recurring condition. Fungal azole-resistant strains with azole-resistance have developed for long and wide explosion to the first-line antifungal azole agent. Bovine lactoferrin (BLF) is a protein from transferrin family secreted by the bovine mammary tissue. Its various biological functions are well known, especially the pronounced antifungal activity. In the current study, we constructed a Lactobacillus casei strain (L.casei/pPG612.1-BLF), which secreted BLF encoded by a mature secretion vector plasmid pPG612.1, and evaluated its antifungal activity in vitro and in vivo. In a two-layer agar plate in vitro assay, the number of C. albicans CFUs decreased and the average colony size shrunk upon exposure to L. casei/pPG612.1-BLF. In a murine VVC model, the infection burden of mice intra-vaginally pre-inoculated with L. casei/pPG612.1-BLF was lower than in control groups. Furthermore, the infection burden in mice with VVC was reduced when the animals were continually given L. casei/pPG612.1-BLF as a topical treatment for 5 days. Combined, these results suggested that the L. casei/pPG612.1-BLF strain is a promising preventative and therapeutic anti-VVC agent, highlighting the possibility of employing the probiotic L. casei as a vehicle for biotherapy in the female genital tract and exploiting the natural antibiotic antimicrobial peptides for other applications.
Thalassemia is a group of common hereditary anemias that cause significant morbidity and mortality worldwide. However, precisely diagnosing thalassemia, especially rare thalassemia variants, is still challenging. Long-range PCR and long-molecule sequencing on the PacBio Sequel II platform utilized in this study could cover the entire HBA1, HBA2 and HBB genes, enabling the diagnosis of most of the common and rare types of thalassemia variants. In this study, 100 cases of suspected thalassemia were subjected to traditional thalassemia testing and third-generation sequencing for thalassemia genetic diagnosis. Compared with traditional diagnostic methods, an additional 10 cases of rare clinically significant variants, including 3 cases of structure variants and 7 cases of single nucleotide variations (SNVs) were identified, of which a case with − α3.7 subtype III (− α3.7III) was first identified and validated in the Chinese population. Other rare variants of 11.1 kb deletions (− 11.1/αα), triplicate α-globin genes (aaa3.7/αα) and rare SNVs have also been thoroughly detected. The results showed that rare thalassemia variants are not rare but have been misdiagnosed by conventional methods. The results further validated third-generation sequencing as a promising method for rare thalassemia genetic testing.