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Background We aimed to evaluate the analytical performance of five commercial RT‐PCR kits (Genekey, Daan, BioGerm, Liferiver, and Yaneng) commonly used in China, since such comparison data are lacking. Methods A total of 20 COVID‐19 confirmed patients and 30 negative nasopharyngeal swab specimens were analyzed by five kits. The detection ability of five RT‐PCR kits was evaluated with 5 concentration gradients diluted by a single positive sample. The limit of detection was evaluated by N gene fragment solid standard. Two positive clinical specimens were used to evaluate the repeatability and imprecision. Finally, we used six human coronaviruses plasmid and four respiratory pathogens plasmid to check for cross‐reactivity. Results The positive detection rate was 100% for Genekey, Daan, and BioGerm,and 90% for Liferiver and Yaneng in 20 clinical SARS‐CoV‐2 infection. The coincidence rate of five kits in 10 negative samples was 100%. The detection rate of target genes for Daan, BioGerm, Liferiver, and Yaneng was 100% from Level 1 to Level 3. In Level 4, only Daan detection rate was 100%. In Level 5, five kits presented poor positive rate. The limit of detection declared by each manufacturer was verified. The repeatability for target genes was less than 5% and so did the total imprecision. There is no cross‐reactivity of five kits with six human coronaviruses and four respiratory pathogens for ORF1ab and N gene. Conclusions Five RT‐PCR kits assessed in this study showed acceptable analytical performance characteristics and are useful tools for the routine diagnosis of SARS‐CoV‐2.

Background Head and neck squamous cell carcinoma (HNSCC) is a malignant tumor with a strong tendency for metastasis and recurrence. Finding effective biomarkers for the early diagnosis of HNSCC is critical for the early treatment and prognosis of patients. Methods RNA sequencing data including long non-coding RNAs (lncRNAs), messenger RNA (mRNAs) and microRNAs (miRNAs) of 141 HNSCC and 44 adjacent normal tissues were obtained from the TCGA. Differentially expressed genes were analyzed using the R package DESeq. GO terms and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses were conducted. A competing endogenous RNAs (ceRNA) network was constructed. The most differentially expressed genes in the main ceRNA network were chosen for nasopharyngeal carcinoma (NPC) cell lines and NPEC2 Bmi-1 cell line verification. A receiver operating characteristic (ROC) curve was constructed for 141 specimens of HNSCC tissues from 44 control samples. Results In our study, 79 HNSCC-associated abnormally expressed lncRNAs , 86 abnormally expressed miRNAs and 324 abnormally expressed mRNAs were identified. The public microarray results showed that LINC00958 and HOXC13-AS expression levels were upregulated in HNSCC tissues compared with the adjacent normal tissues in this study (p < 0.0001). LINC00958 and HOXC13-AS expression levels in NPC cell lines were higher than those in the NPEC2 Bmi-1 cell line (p < 0.05). The results showed that the area under the ROC curve (AUC) of LINC00958 reached up to 0.906 at a cutoff value of 7.96, with a sensitivity and specificity of 80.85% and 90.91%, respectively. The AUC of HOXC13-AS reached up to 0.898 at a cutoff value of 0.695, with sensitivity and specificity values of 86.23% and 83.78%, respectively. Conclusion The current study indicates that LINC00958 and HOXC13-AS are new candidate diagnostic biomarkers for HNSCC patients.

Background Seldom performance evaluation and diagnosis comparison studies were reported for different chemiluminescent immunoassay (CLIA) kits approved under an emergency approval program for SARS‐CoV‐2 infection. Methods A total of 100 and 105 serum separately from non‐infected populations and COVID‐19 patients were detected with SARS‐CoV‐2 IgM and IgG kits. The characteristics including precision, functional sensitivity, linearity, and accuracy were evaluated for Axceed, iFlash, and Maglumi CLIA kits. Results Maglumi and iFlash had the best analytical sensitivity for IgM and IgG, respectively. Axceed kits had a linearity response in the detected concentration. The clinical sensitivity of Axceed, iFlash, and Maglumi was 68.0%, 64.9%, and 63.9% with a specificity of 99.0%, 96.0%, and 100% for IgM, 85.6%, 97.9%, and 94.8% with a specificity of 97.0% for IgG. ROC analysis indicated all kits had a diagnostic power greater than 0.9. Notably, either IgM or IgG kits obtained a poor agreement (Kappa value from 0.397 to 0.713) with others. Among 38 recovered patients, 94.7% had an effective immune response, and both seropositive IgM and IgG accounted for the biggest proportion (medium, 42 days onset), then followed by the single seropositive IgG (medium, 50 days onset) in Ab profile. Conclusion The performance of CLIA kits satisfied the diagnosis of SARS‐CoV‐2 infection. Both positive of IgG and IgM contributes to improve the specificity, and a positive one will enhance the sensitivity.