Objective:To explore the genetic diversity of Mycobacterium tuberculosis (MTB) in different types of tuberculosis and its association with clinical features, providing evidence for precise diagnosis and treatment of tuberculosis. Methods:This cross-sectional study included 103 cases of tuberculosis (38 with simple pulmonary tuberculosis, 43 with tuberculous pleurisy, and 22 with pulmonary combined with extrapulmonary tuberculosis) from Shenzhen Third People′s Hospital from 2015 to 2018. Paired bacterial strains from lung and pleural effusion/extrapulmonary sites were collected. Whole-genome sequencing (WGS) was used for drug resistance prediction, and genetic diversity (π value) was calculated as well as differential genes screening. Statistical analysis included paired t-tests and χ2 tests to compare clinical, bacteriological and genetic diversity features among groups.Results:The simple pulmonary tuberculosis group exhibited significantly higher rates of retreatment (71.7%, 27/38), cavitation (70.4%, 19/27), and multidrug-resistant or rifampicin-resistant (MDR/RR) (60.5%, 23/38) compared to the tuberculous pleurisy group (retreatment 11.9%, 5/42; cavitation 11.9%, 5/42; MDR/RR 16.3%, 7/43) and extrapulmonary tuberculosis group (retreatment 9.1%, 2/22; cavitation 18.2%, 4/22; MDR/RR 13.6%, 3/22) ( P<0.05). The overall π values of the MTB strain genomes in lung [(5.94±3.93)×10 ?5], pleural effusion[(6.22±3.51)×10 ?5], and extrapulmonary tissues [(5.83±3.54)×10 ?5] showed no significant differences ( H=0.10, P=0.94). Differential gene diversity analysis revealed that π value alternating genes related to respiration and intermediate metabolism were prominently high [tuberculous pleurisy 32.4% (11/34) and extrapulmonary tuberculosis groups 31.4% (32/102)], while cell wall-associated genes dominated in the simple pulmonary tuberculosis group (42.9%, 6/14). Drug resistance profiles and mutation spectra were identical across isolates from different sites within the same patient. Conclusion:WGS revealed the MTB diversity among different types of tuberculosis. Difference between pulmonary and extrapulmonary environments may impel the adaptive alternations of the bacterial strains to maintain survival with higher overall genome stability. Drug resistance testing of lung-derived isolates may provide references on extrapulmonary tuberculosis treatment.

Objective:To explore the genetic diversity of Mycobacterium tuberculosis (MTB) in different types of tuberculosis and its association with clinical features, providing evidence for precise diagnosis and treatment of tuberculosis. Methods:This cross-sectional study included 103 cases of tuberculosis (38 with simple pulmonary tuberculosis, 43 with tuberculous pleurisy, and 22 with pulmonary combined with extrapulmonary tuberculosis) from Shenzhen Third People′s Hospital from 2015 to 2018. Paired bacterial strains from lung and pleural effusion/extrapulmonary sites were collected. Whole-genome sequencing (WGS) was used for drug resistance prediction, and genetic diversity (π value) was calculated as well as differential genes screening. Statistical analysis included paired t-tests and χ2 tests to compare clinical, bacteriological and genetic diversity features among groups.Results:The simple pulmonary tuberculosis group exhibited significantly higher rates of retreatment (71.7%, 27/38), cavitation (70.4%, 19/27), and multidrug-resistant or rifampicin-resistant (MDR/RR) (60.5%, 23/38) compared to the tuberculous pleurisy group (retreatment 11.9%, 5/42; cavitation 11.9%, 5/42; MDR/RR 16.3%, 7/43) and extrapulmonary tuberculosis group (retreatment 9.1%, 2/22; cavitation 18.2%, 4/22; MDR/RR 13.6%, 3/22) ( P<0.05). The overall π values of the MTB strain genomes in lung [(5.94±3.93)×10 ?5], pleural effusion[(6.22±3.51)×10 ?5], and extrapulmonary tissues [(5.83±3.54)×10 ?5] showed no significant differences ( H=0.10, P=0.94). Differential gene diversity analysis revealed that π value alternating genes related to respiration and intermediate metabolism were prominently high [tuberculous pleurisy 32.4% (11/34) and extrapulmonary tuberculosis groups 31.4% (32/102)], while cell wall-associated genes dominated in the simple pulmonary tuberculosis group (42.9%, 6/14). Drug resistance profiles and mutation spectra were identical across isolates from different sites within the same patient. Conclusion:WGS revealed the MTB diversity among different types of tuberculosis. Difference between pulmonary and extrapulmonary environments may impel the adaptive alternations of the bacterial strains to maintain survival with higher overall genome stability. Drug resistance testing of lung-derived isolates may provide references on extrapulmonary tuberculosis treatment.

Objective:To isolate and identify SARS-CoV-2 epidemic strains and analyze the sequence characteristics of the virus strains following serial passages.Methods:Eleven nasopharyngeal swabs positive for SARS-CoV-2 antigen were collected from December 2022. Quantitative real-time PCR was used to detect SARS-CoV-2 nucleic acid, and positive specimens were inoculated onto Vero cells for virus isolation. The isolated strains were identified by Western blot and indirect immunofluorescence assay. The morphology of the isolated strains was observed using transmission electron microscopy. Nucleic acid was extracted from the isolates and passaged viruses for further sequencing and analysis.Results:All 11 specimens tested positive for SARS-CoV-2 using quantitative real-time PCR. SARS-CoV-2 strains were successfully isolated from seven specimens, and could be adaptively cultured, passaged, and expanded on Vero cells, achieving a peak titer exceeding 10 6.25 50% cell culture infectious dose (CCID 50)/ml. Western blot and indirect immunofluorescence results showed that the isolates could be specifically recognized by monoclonal antibodies and convalescent serum against SARS-CoV-2. Transmission electron microscopy revealed oval-shaped viral particles with diameters of approximately 100 nm. Next-generation sequencing of the viral isolates demonstrated a sequence homology greater than 99.50% with the Wuhan-Hu-1 reference strain (NC_045512) and 99.98% among the seven isolated strains, and all of the isolates belonged to the Omicron BF.7 variant. Sequence analysis after continuous passage and plaque purification of the BJ-NVSI-20230005 isolate showed that compared with passages 1-3, passages 4-6 had one nucleotide site mutation (C→T) in the ORF1ab gene and a deletion of 3 bp in the E gene, which resulted in a change from leucine to phenylalanine and the deletion of valine, respectively. Polymorphisms were observed in the sequences of plaque-purified clones. Conclusions:The seven successfully isolated SARS-CoV-2 strains all belong to the SARS-CoV-2 BF.7 variant, which is consistent with the prevalence trend in mainland China in December 2022.

Objective To investigate the bacterial community diversity in human Demodex mites, so as to provide insights into unraveling the role of human Demodex mites in them caused infectious diseases. Methods From June to July 2023, Demodex mites were collected from the faces of college students in a university in Wuhu City using the adhesive tape method, and the V4 region of 16S ribosomal RNA (16S rRNA) gene and the internal transcribed spacer (ITS) gene of nuclear ribosomal DNA were amplified on an Illumina PE250 high-throughput sequencing platform. Sequencing data were spliced according to the overlapping relations and filtered to yield effective sequences, and operational taxonomic units (OTUs) was clustered. The diversity index of obtained OUTs was analyzed, and the structure of the bacterial community was analyzed at various taxonomic levels. Results A total of 57 483 valid sequences were obtained using 16S rRNA gene sequencing, and 159 OUTs were classified according to similarity. Then, OUTs at a 97% similarity were included for taxonomic analyses, and the bacteria in Demodex mites belonged to 14 phyla, 20 classes, 51 orders, 72 families, and 94 genera. Proteobacteria was the dominant phylum, and Vibrio, Bradyrhizobium and Variovorax were dominant genera. A total of 56 362 valid sequences were obtained using ITS gene sequencing, and 147 OTUs were obtained, which belonged to 5 phyla, 17 classes, 34 orders, 68 families, and 93 genera and were annotated to Ascomycota, Basidiomycota and Chytridiomycota, with Ascomycota as the dominant phylum, and Alternaria alternata, Epicoccum, Penicillium, and Sarocladium as dominant genera. Conclusions There is a high diversity in the composition of bacterial communities in human Demodex mites, with multiple types of microorganisms and high species abundance.

To observe whether PCSK9 inhibitor combined with statin therapy can bring additional benefits on near-term clinical prognosis in patients with acute cerebral infarction，in order to provide clinical data on the effects of PCSK9 inhibitors in the early treatment of patients with cerebral infarction. Methods124 patients with acute cerebral infarction admitted to the neurology ward of our hospital from December 2020 to July 2021 were included as study subjects. A 90-day clinical follow-up was used to compare the differences in hematological indices，clinical neurological function scores，documentation of recurrent cerebral infarction and other thrombotic events during the follow-up period and differenses in the time to recurrence between the PCSK9 inhibitor combined with statin treatment and standard statin treatment groups. ResultsThe levels of hs-CRP，IL-6，Lp-PLA2，HCY，TC and LDL-C，NIHSS score and mRS score in the PCSK9 inhibitor combined with statin treatment group and the standard statin treatment group were all decreased before and after treatment（P<0.05），and there was a statistically significant difference in the combined treatment group（P<0.05），and lowered TG（P<0.05），while the level of HDL-C was improved（P<0.05）. There was no statistical significance in fasting plasma glucose of both groups before and after treatment（P>0.05）. Compared with the combined treatment group，the recurrence rate of cerebral infarction in the standard treatment group was obviously high（χ2=7.694，P=0.006），while the time to cerebral infarction recurrence was significantly longer in the combined treatment group（P<0.05）. ConclusionPCSK9 inhibitors can effectively reduce peripheral inflammatory response，promote neurological function recovery，significantly reduce stroke recurrence rate，and significantly prolong the recurrence time.