OBJECTIVES: To investigate the efficacy of Ag₂Se nanoparticles for eliminating intracellular Porphyromonas gingivalis (P. gingivalis) in esophageal cancer and examine the effect of P. gingivalis clearance on progression of esophageal cancer. METHODS: Ag₂Se nanoparticles were synthesized via a chemical synthesis method. The effects of Ag₂Se nanoparticles on P. gingivalis viability and colony-forming ability were assessed using fluorescence staining and colony formation assays. In a mouse model bearing subcutaneous murine esophageal cancer cell allograft with P. gingivalis infection, the effect of treatment with Ag₂Se nanoparticles on the abundance of P. gingivalis in the tumor tissues was quantified using RNAscope in situ hybridization and quantitative polymerase chain reaction (qPCR), and the changes in tumor volume were monitored. The biosafety of Ag₂Se nanoparticles was assessed by examining liver and kidney functions and pathological changes in the major organs of the mice. RESULTS: Transmission electron microscopy revealed that the synthesized Ag₂Se nanoparticles were uniformly dispersed spherical particles with a diameter around 50 nm. In vitro experiments demonstrated that exposure to Ag₂Se nanoparticles significantly reduced the viability and clonal proliferation capacity of P. gingivalis in a dose-dependent manner. In the tumor-bearing mice, treatment with Ag₂Se nanoparticles significantly reduced the abundance of P. gingivalis in tumor tissues and suppressed tumor cell proliferation. No significant damages to the liver and kidney functions or the major organs were observed in Ag₂Se nanoparticle-treated mice, demonstrating good biocompatibility of Ag₂Se nanoparticles. CONCLUSIONS Ag₂Se nanoparticles exhibit significant bactericidal and inhibitory effects against P. gingivalis, and can effectively eliminate intracellular P. gingivalis to suppress the growth of esophageal cancer allograft in mice, suggesting the potential of Ag₂Se nanoparticles in the treatment of esophageal cancer.
Animals ; Porphyromonas gingivalis/drug effects* ; Mice ; Esophageal Neoplasms/pathology* ; Nanoparticles ; Metal Nanoparticles ; Bacteroidaceae Infections ; Cell Line, Tumor

Objective: To understand the possible transmission route of a family cluster of COVID-19 in Zhengzhou and the potential infectivity of COVID-19 in incubation period, and provide scientific evidence for the timely control of infectious source and curb the spread of the epidemic. Methods: Epidemiological investigation was conducted for a family cluster of COVID-19 (8 cases) with descriptive epidemiological method, and respiratory tract samples of the cases were collected for the nucleic acid detection of 2019-nCoV by RT-PCR. Results: Two primary cases, which occurred on 31 January and 1 February, 2020, respectively, had a common exposure history in Wuhan. The other six family members had onsets on 30 January, 31 January, 1 February (three cases) and 3 February, 2020. Conclusions In this family cluster of COVID-19, six family members were infected through common family exposure to the 2 primary cases. Five secondary cases had onsets earlier than or on the same day as the primary cases, indicating that COVID-19 is contagious in incubation period, and the home isolation in the early phase of the epidemic might lead to the risk of family cluster of COVID-19.

Objective: To isolate and identify Prevotella nigrescens (P.nigrescens) in gingival crevicular fluid of patients with chronic periodontitis and to analyze its tumor-promoting role in esophageal squamous cell carcinoma (ESCC). Methods: Samples of gingival crevicular fluid were collected from patients with chronic periodontitis and cultured on GAM agar medium under anaerobic conditions. Black colonies on GAM agar plates were picked for subculture, and then the bacteria were isolated and purified. Bacterial identification was conducted using Gram staining and 16S rDNA sequencing analysis. The isolated bacterial species was used to infect ESCC NE6-T cells and the changes in biological characteristics of the infected cells were evaluated. Results: Multiple bacterial colonies were observed after anaerobic culturing of gingival crevicular fluid samples for 120 h on GAM agar plates. A single bacterial colony with pure black and smooth appearance was obtained from grey black bacterial colonies with streak method. It was a Gram-negative bacterium with bead-like shape. It showed 99.78% 16S rDNA sequence identity with P. nigrescens F0103 and was named P. nigrescens LY01. P. nigrescens LY01 infection promoted the in vitro proliferation, migration and invasion of NE6-T cells and the growth of subcutaneous xenograft in nude mice. In addition, it could also induce the upregulation of Ki67 and activation of p-STAT3. Conclusions P. nigrescens inhabiting in gingival sulcus might promote the progression of ESCC in human with chronic periodontitis.

Objective To develop and validate a method for detecting factor 8 gene (F8) mutations in hemophilia A patients by Ion Torrent semiconductor sequencing .Methods Intron 22 and intron 1 inversions of F8 gene were identified by long distance PCR (LD-PCR), other mutations in the F8 gene were identified by Ion Torrent sequencing.Candidate variants were validated by Sanger sequencing .Sanger sequencing was applied to screen HA carriers from 11 female family members in the 8 pedigrees.One pregnant woman was offered prenatal diagnosis via analyzing the fetal DNA obtained through amniocentesis . Results Four missense mutations ( c.1331A >C, 1648C >T, c.6506G >A, c.6544C >T), two frameshift mutations ( c.2393 _2394insT, c.6320delG), one splicing mutation ( IVS5 +5G >A), one nonsense mutation (c.43C >T) and one Inv22 mutation were identified in all nine probands respectively . Among 11 female family members, 10 females were identified to be HA carriers, and one didn′t carry the maternal pathogenic mutation.Prenatal diagnosis result showed that the fetus inherited the wild -type maternal allele and was predicted to be unaffected by HA .Conclusion The targeted Ion Torrent sequencing is a reliable and efficient method to detect F8 mutations in patients with Hemophilia A disease .