We developed a visual and rapid reverse transcription–loop-mediated isothermal amplification (RT-LAMP) assay targeting the S gene for SARS-CoV-2 infection. The strength of our study was that we validated the RT-LAMP assay using 481 clinical respiratory samples from two prospective cohorts of suspected COVID-19 patients and on the serial samples from an asymptomatic carrier. The developed RT-LAMP approach showed an increased sensitivity (88.89%) and high consistency (kappa, 0.92) compared with those of reverse transcription-quantitative PCR (RT-qPCR) for SARS-CoV-2 screening while requiring only constant-temperature heating and visual inspection, facilitating SARS-CoV-2 screening in well-equipped labs as well as in the field. The time required for RT-LAMP was less than 1 h from sample preparation to the result (more than 2 h for RT-qPCR). This study showed that the RT-LAMP assay was a simple, rapid, and sensitive approach for SARS-CoV-2 infection and can facilitate COVID-19 diagnosis, especially in resource-poor settings.

Background: Stomach adenocarcinoma (STAD) is associated with high morbidity and mortality rates. Ferroptosis is an iron-dependent form of cell death, which plays an important role in the development of many cancers. Tumor-associated competing endogenous RNAs (ceRNAs) regulate tumorigenesis and development. Our study aimed to construct ceRNA networks and explore the relationship between ferroptosis-related genes in the ceRNA network and immune infiltration in STAD. Methods: Based on the interactions among long noncoding RNAs (lncRNAs), microRNAs (miRNAs), and messenger RNAs (mRNAs), a ceRNA network was constructed to illustrate the relationships among lncRNAs, miRNAs, and mRNAs. Subsequently, gene ontology (GO) and Kyoto encyclopedia of genes and genomes (KEGG) functional enrichment analyses were carried out to explore the functions and interactions of the differentially expressed (DE) mRNAs related to the ceRNA network. Differential expression and prognostic analysis of ferroptosis-related genes in the ceRNA network were performed using the R package “limma” and “survminer.” The correlation between ferroptosis-related genes and tumor-infiltrating immune cells was analyzed using Spearman correlation analysis and CIBERSORT. Quantitative real-time PCR (qRT-PCR) was used to validate the expression of ferroptosis-related genes in STAD cells lines. Results: A ceRNA network consisting of 29 DElncRNAs, 31 DEmiRNAs, and 182 DEmRNAs was constructed. These DEmRNAs were significantly enriched in pathways related to the occurrence and development of STAD. The ferroptosis-related gene SLC1A5 was upregulated in STAD (P < 0.001) and was associated with better prognosis (P = 0.049). The CIBERSORT database and Spearman correlation analysis indicated that SLC1A5 was correlated with eight types of tumor-infiltrating immune cells and immune checkpoints, including PD-L1(CD-274) and PD-1(PDCD1). The SLC1A5 mRNA was found to be highly expressed in STAD cells lines. Conclusions: Our study provides insights into the function of ceRNAs in STAD and identifies biomarkers for the development of therapies for STAD. The ferroptosis-related gene SLC1A5 in the ceRNA network was associated with both tumor-infiltrating immune cells and immune checkpoints in the tumor microenvironment, suggesting that SLC1A5 may be a novel prognostic marker and a potential target for STAD immunotherapy in the future.

The speckle tracking ultrasound is an innovative technology enabling distinct assessment of diaphragmatic movement, yet the relative data are scarce. In this pilot study, we sought to evaluate the predictive value of the weaning outcome of automatic speckle tracking in assessing diaphragm excursion. This is a prospective, multicenter, observational study. A total of 160 critically ill subjects underwent speckle-tracking ultrasonography of the right/left hemidiaphragm before the spontaneous breathing trial. Meanwhile, the diaphragm excursion and velocity values were measured manually by M-mode ultrasound. Patients were divided into weaning-failure and weaning-success groups. The correlation was assessed between automatic and manual measurement, and the diagnostic efficacy of automatic measured excursion and velocity for predicting weaning outcome was analyzed. A total of 88 patients completed the follow-up of the weaning outcome. The overall incidence of weaning failure was 43.18%. There was a significant correlation between the automatic measurement of mean excursion and velocity assessed by speckle tracking imaging and manual measurement (R 0.69 and 0.65, respectively). Receiver operating characteristic (ROC) curve analysis showed that the mean excursion and diaphragmatic velocity exhibited high diagnostic values for prolonged weaning [area under the ROC curve (AUROC) 0.824 and 0.786, respectively]. The diaphragmatic excursion showed moderate diagnostic value for predicting both weaning failure and in-hospital death/withdrawal of treatment (AUROC 0.659 and 0.653, respectively). Automatic speckle tracking analysis of the diaphragm showed high consistency with conventional manual ultrasound measures. Diaphragmatic excursion and its excursion velocity helped predict mechanical ventilation weaning failure, prolonged weaning, as well as in-hospital adverse outcomes, which served as a reliable tool in guiding clinical weaning strategy.

Objectives: This study aimed to explore changes in carbapenem-resistant Klebsiella pneumoniae (CR-KP) isolates collected in Guangdong over the period of 2016–2020.Methods: Antibacterial susceptibility was quantified through VITEK 2 compact and K-B method. Carbapenemase phenotypes and genotypes were characterized by modified carbapenem inactivation method (mCIM), EDTA-carbapenem inactivation method (eCIM), and polymerase chain reaction (PCR). Molecular characteristics and evolutionary trends were analyzed by multilocus sequence typing and evolutionary tree.Results: Isolates (2,847) of K. pneumoniae were separated in 2016–2020, and the separate rate of CR-KP increased from 5.65 to 9.90% (p = 0.009). The top 3 wards were intensive care unit (ICU) (21.92%), neonatal wards (13.70%), and respiratory wards (12.33%). In 146 CR-KP strains, serine carbapenemase was the main phenotype, and KPC was the main genotype, and 57 contained two resistant genes, and 1 contained three resistant genes. Two polygenic strains were first found: IMP + GES and KPC + NDM + VIM, but all the phenotypes were metalloenzyme, which indicated that metalloenzyme was usually the first choice for CR-KP resistance. In addition, all the ST54 of metalloenzyme type contained IMP, and all the ST45, ST37, and ST76 contained OXA. ST11 was the most prevalent (42.47%); ST11 and its mutants proved the predominant sequence type making up 51.1% of the carbapenemase-producing isolates. A novel type of ST11 mutation, the rpoB was mutated from sequence 1 to sequence 146, was in an independent separate branch on the evolutionary tree and was resistant to all antibacterial agents. The other three mutants, rpoB 1–15, infB 3–148, and infB 3–80, are also resistant to all antibacteria. Of note, all the four mutants produced serine carbapenemase and contained KPC, and indicated that the prevalent strain in China, ST11, has serious consequences and potential outbreaks.Conclusion: The infection rate of CR-KP has increased, and ICU and neonatal wards have become the key infection areas. Producing serine enzyme, the KPC genotype, and ST11 are the predominant CR-KP. Polygenic strains and ST11 mutation made clinical treatment difficult and may become a potential threat.

Background: Approximately 10% of gastric cancers (GCs) are associated with strong familial clustering and can be attributed to genetic predisposition. Homologous recombination deficiency (HRD) leads to genomic instability and accumulation of genetic variations, playing an important role in the development and progression of cancer. We aimed to delineate the germline mutation characteristics of patients with HRD-mut GC in Chinese. Methods: We retrospectively reviewed the genomic sequencing data of 1135 patients with Chinese GC. Patients harbouring at least one loss of function (LoF) germline mutations in BRCA1, BRCA2, ATM, PALB2, BRIP1, CHEK1, CHEK2, FANCA and FANCL were selected for analysis. Results: 89 patients were identified with LoF germline mutations of HRD gene. Germline mutations occurred most commonly in ATM (30.33%), followed by BRIP1 (17.98%), BRCA2 (14.61%), BRCA1 (12.36%), FANCA (10.11%), PALB2 (10.11%), FANCL (6.74%), CHEK1 (3.37%) and CHEK2 (3.37%). 14 out of 89 patients with HRD-mut harboured double mutations in HRD and MMR genes, with the median age of 51.5 years. The decreasing median age would be attributed to five patients with HRD+MMR double-muts harbouring mutations in both HRD and MMR genes. The median age of onset of patients with HRD+MMR double-muts is 47, which is significantly earlier than that of Chinese patients with GC (p=0.0235). Conclusion: Our data suggest that carrying both HRD and MMR gene LoF germline mutations may cause early-onset GC. Germline mutations in the HRD gene should be of concern in the study of hereditary GC.