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Rapid detection of bloodstream pathogens would greatly facilitate clinicians to make precise antimicrobial treatment in patients with bacteremia. In this study, 114 plasma samples were collected from patients with identified or suspected bacteremia, and pathogens were detected by the conventional blood culture (BC) and cell-free DNA metagenomics next-generation sequencing (cfDNA mNGS). The present study indicated that 76% (38/50) of positive conventional blood culture (BC+ group) patients were positively detected by cfDNA mNGS, and only 4% were mismatched between cfDNA mNGS and conventional bacteria culture. Pathogens in 32.8% of suspected bacteremia patients with negative conventional blood culture (BC– group) were determined accurately by cfDNA mNGS combined with analyzing the patients’ clinical manifestations. Escherichia coli and Klebsiella pneumoniae were the most detected pathogens in identified bacteremia patients by cfDNA mNGS. 76.2% (16/21) of E. coli and 92.3% (12/13) of K. pneumoniae in bacteremia patients were identified by conventional blood cultures that were also detected by cfDNA mNGS. This study demonstrated that genomic coverage of E. coli and K. pneumoniae were more often detected in BC+ group patients and genomic coverage of Acinetobacter johnsonii and Paucibacter sp. KCTC 42545 was more often detected in BC– group patients. In conclusion, cfDNA mNGS could rapidly and precisely provide an alternative detection method for the diagnosis of bacteremia.

Coronavirus disease 2019 (COVID-19) has become a global pandemic with a high rate of transmission. Currently, there is a lack of vaccines and specific drugs for this newly-emerged virus. Timely diagnosis and treatment, as well as isolation of patients and virus carriers, contribute to the effective prevention and control of this epidemic. This review focuses on early stage COVID-19 diagnosis methods and strategies, highlighting the guiding role of laboratory indicators on treatment strategy formulation, and prognosis assessments.

In order to find out the reason of large area roof cutting and caving in abandoned roadway during the mode of mining one side pillar and three-roadway arrangement of 202 working face in Daning Coal Mine, based on the field observation and theoretical analysis of mine pressure, the mechanical model of the overlying strata in the abandoned roadway is established, and the mechanism and countermeasures of roof cutting and caving are analyzed and practiced. The research results and field practice show that unreasonable support causes the basic roof above the roadway to break in advance, and the sliding of the “long key block” is unstable, which is the root reason of the basic roof cutting and caving. When the back-filling measures are taken and back-filling strength of the abandoned roadway is 1 MPa to 1.2 MPa, it can control the coal wall and roof subsidence effectively and the stress state around the abandoned roadway can be greatly improved to form a situation that is conducive to passing through the abandoned roadway, ensuring the mining succeed.

The pandemic spread of African swine fever (ASF) has caused serious effects on the global pig industry. Virus genome sequencing and genomic epidemiology analysis play an important role in tracking the outbreaks of the disease and tracing the transmission of the virus. Here we obtained the full-length genome sequence of African swine fever virus (ASFV) in the first outbreak of ASF in China on August 3rd, 2018 and compared it with other published genotype II ASFV genomes including 9 genomes collected in China from September 2018 to October 2020. Phylogenetic analysis on genomic sequences revealed that genotype II ASFV has evolved into different genetic clusters with temporal and spatial correlation since being introduced into Europe and then Asia. There was a strong support for the monophyletic grouping of all the ASFV genome sequences from China and other Asian countries, which shared a common ancestor with those from the Central or Eastern Europe. An evolutionary rate of 1.312 × 10−5 nucleotide substitutions per site per year was estimated for genotype II ASFV genomes. Eight single nucleotide variations which located in MGF110-1L, MGF110-7L, MGF360-10L, MGF505-5R, MGF505-9R, K145R, NP419L, and I267L were identified as anchor mutations that defined genetic clusters of genotype II ASFV in Europe and Asia. This study expanded our knowledge of the molecular epidemiology of ASFV and provided valuable information for effective control of the disease. [ABSTRACT FROM AUTHOR]

This study was conducted to investigate oropharyngeal microbiota alterations during the progression of coronavirus disease 2019 (COVID-19) by analyzing these alterations during the infection and clearance processes of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The diagnosis of COVID-19 was confirmed by using positive SARS-CoV-2 quantitative reverse transcription polymerase chain reaction (RT-qPCR). The alterations in abundance, diversity, and potential function of the oropharyngeal microbiome were identified using metatranscriptomic sequencing analyses of oropharyngeal swab specimens from 47 patients with COVID-19 (within a week after diagnosis and within two months after recovery from COVID-19) and 40 healthy individuals. As a result, in the infection process of SARS-CoV-2, compared to the healthy individuals, the relative abundances of Prevotella, Aspergillus, and Epstein–Barr virus were elevated; the alpha diversity was decreased; the beta diversity was disordered; the relative abundance of Gram-negative bacteria was increased; and the relative abundance of Gram-positive bacteria was decreased. After the clearance of SARS-CoV-2, compared to the healthy individuals and patients with COVID-19, the above disordered alterations persisted in the patients who had recovered from COVID-19 and did not return to the normal level observed in the healthy individuals. Additionally, the expressions of several antibiotic resistance genes (especially multi-drug resistance, glycopeptide, and tetracycline) in the patients with COVID-19 were higher than those in the healthy individuals. After SARS-CoV-2 was cleared, the expressions of these genes in the patients who had recovered from COVID-19 were lower than those in the patients with COVID-19, and they were different from those in the healthy individuals. In conclusion, our findings provide evidence that potential secondary infections with oropharyngeal bacteria, fungi, and viruses in patients who have recovered from COVID-19 should not be ignored; this evidence also highlights the clinical significance of the oropharyngeal microbiome in the early prevention of potential secondary infections of COVID-19 and suggests that it is imperative to choose appropriate antibiotics for subsequent bacterial secondary infection in patients with COVID-19. [ABSTRACT FROM AUTHOR]

To identify viral pathogens in patients with secondary glaucoma associated with anterior segment uveitis and compare metagenomic deep sequencing (MDS) with enzyme-linked immunosorbent assay (ELISA) combined with Witmer-Desmonts coefficient (WDC) evaluation and real-time quantitative polymerase chain reaction (qPCR) on investigating pathogens in aqueous humor. Aqueous humor from 31 patients, including 22 Posner-Schlossman Syndrome and 9 other anterior uveitis, was assessed pathogens by ELISA combined with WDC evaluation, virus deoxyribonucleic acid (DNA) detection by real-time qPCR and MDS. Viral pathogens (HCMV or VZV or RV) were detected in 19 out of 31 eyes (61.3%) by real-time qPCR or WDC evaluation. MDS revealed the presence of HCMV DNA sequences in three PSS patients. Virus is an important pathogen in secondary glaucoma associated with anterior segment uveitis. MDS is a potential etiologic diagnosis tool to seek intraocular viral pathogens for secondary glaucoma associated anterior segment uveitis. [ABSTRACT FROM AUTHOR]