Objective:To explore the hypothesis of "pathogen storage pool" by analyzing the local microbial community of adenoids. Methods:Under the guidance of a 70° nasal endoscope, sterile swabs were used to collect secretions from the adenoid crypts of the subjects. The samples were sent to the laboratory for DNA extraction and standard bacterial 16S full-length sequencing analysis. Results:At the species level, the top three microbial communities in adenoid crypts were Bacillus subtilis（18.78%）, Fusobacterium pyogenes（11.42%）, and Streptococcus pneumoniae（9.38%）. Conclusion:The local microbial community of adenoids exhibits a high degree of diversity, including microbial communities from the oral cavity and gastrointestinal tract. Our research results support the hypothesis that adenoids act as a " pathogen reservoir".
Humans ; Adenoids/microbiology* ; RNA, Ribosomal, 16S/genetics* ; Microbiota/genetics* ; Streptococcus pneumoniae/isolation & purification* ; Bacillus subtilis/genetics* ; DNA, Bacterial/analysis*

OBJECTIVES: To detect prfA and hly toxin genes of Listeria monocytogenes using polymerase chain reaction (PCR) and colloidal gold technology. METHODS: L. monocytogenes DNA was extracted by boiling method. With prfA and hly of L. monocytogenes as the target genes, the 5' ends of upstream and downstream primers of prfA gene were labeled with 6-FAM and biotin, and the 5' ends of upstream and downstream primers of hly gene were labeled with digoxin and biotin, respectively, to establish the toxin gene detection method. Using cloning transformation, sequencing analysis, cloning of positive control products, the detection kid was developed and its specificity, sensitivity, reproducibility and stability were tested, followed by verification with sample testing. RESULTS: The concentration of L. monocytogenes DNA extracted by boiling method was 148.81±0.97 ng/μL, and the A₂₆₀/A₂₈₀ ratio ranged from 1.8 to 2.0. The PCR products showed a 100% homology with the gene sequences in GenBank database after cloning, transformation and sequencing. The colloidal gold strip yielded positive results only for L. monocytogenes samples without cross-reactions with Staphylococcus aureus, Escherichia coli or Bacillus cereus, and its minimum detection limit was 10^-2 ng/μL, demonstrating a 10-fold greater sensitivity of the test than agarose gel electrophoresis. The test also showed good reproducibility of the results when performed by different operators with good stability of the test strips after storage for 6 to 12 months. The test results showed that this kit could accurately and quickly detect L.monocytogenes in the test samples. CONCLUSIONS The detection kit developed in this study can simultaneously detect prfA and hly toxin genes of L. monocytogenes with good specificity, sensitivity, reproducibility and stability for use in food safety inspection.
Listeria monocytogenes/isolation & purification* ; Gold Colloid ; Bacterial Toxins/genetics* ; Polymerase Chain Reaction/methods* ; Hemolysin Proteins/genetics* ; Bacterial Proteins/genetics* ; DNA, Bacterial/genetics* ; Food Microbiology ; Heat-Shock Proteins

OBJECTIVES: To explore the possibility of using human skin and oral microorganisms to estimate the geographic origin of an individual through the sequencing analysis of bacterial 16S rRNA gene. METHODS: Microbial DNA was extracted from the palm and oral microorganisms of the Han population in Shanghai and Chifeng, Inner Mongolia, and the composition and diversity of the microbiota were analyzed by full-length 16S rRNA gene sequencing. Then, differential species were screened and a geographic location prediction model was constructed. RESULTS: The compositions of palm and oral microorganisms between Shanghai and Chifeng samples were both different. The abundance and uniformity of palm side skin microorganisms were higher in Chifeng samples than in Shanghai samples, while there was no significant difference in oral microorganisms. Permutational multivariate analysis of variance (PERMANOVA) confirmed that the β-diversity between the samples from the two places were statistically significant, and the coefficients of determination (R²) for skin and oral samples were 0.129 and 0.102, respectively. Through principal co-ordinates analysis (PCoA), the samples from the two places could be preliminarily distinguished. The predictive model had the accuracies of 0.90 and 0.83 for the geographic origin using the skin and oral samples, respectively. CONCLUSIONS There are differences in the compositions of palm and oral microbiota between Han populations in Shanghai and Chifeng. The prediction model constructed by the random forest algorithm can trace the unknown individuals from the above two places.
Humans ; China ; DNA, Bacterial/genetics* ; Microbiota/genetics* ; RNA, Ribosomal, 16S/genetics* ; Skin/microbiology* ; Forensic Genetics ; High-Throughput Nucleotide Sequencing ; Mouth/microbiology*

Objective: To explore the possibility that the intestinal flora profile in complex anal fistula patients is different to that of healthy controls. This was assessed by sequencing of 16S rDNA in fecal samples from cohorts representing these populations. Methods: Fecal samples were collected from 30 complex anal fistula patients and 30 matched healthy controls. Patients were included if they met the diagnostic criteria of cryptoglandular anal fistula and had exhibited symptoms for more than 3 months. Complex anal fistula is diagnosed under the following circumstances: if the fistula in question spans 2/3 or more of the diameter of the anal sphincter; if there are more than two external orifices or fistula tracks; or if recurrence is observed after previous anal fistula surgery. Patients were excluded if there were comorbities including inflammatory bowel disease (as assessed by colonoscopy), chronic diarrhea, chronic constipation, diabetes, gastrointestinal malignancies, liver/ kidney dysfunction, or cognitive impairment. Patients whose anal fistulas were caused by Crohn's disease, trauma, special infections (such as actinomycosis and tuberculosis) were also excluded, as were those who had used antibiotics, prebiotics, or probiotics that may affect intestinal microecology in the month prior to the study. Total bacterial genomic DNA was extracted by PCR amplification of the V4 hypervariable region of the 16S rRNA sequences. High-throughput sequencing and data analysis were performed on the Illumina Miseq platform. Finally, operational taxonomic unit (OTU) clustering, alpha diversity and LEfSE data analysis were carried out. The larger the Chao or ACE index is, the higher the species abundance of the microflora is expected to be. Similarly, a smaller value for the Simpson index or a larger value for the Shannon index indicates greater microflora diversity. There was no statistically significant difference in gender, age, body mass index (BMI), drinking history, or smoking history between the two groups (P>0.05), indicating that they were comparable. Results: The α-diversity analysis including ACE, Chao, Shannon and Simpson indexes indicated a richer diversity of intestinal microflora in complex anal fistula patients than in healthy controls. In both patients and controls, OUT cluster analysis demonstrated that 93.4%±32.0% and 87.4%±41.2% of sequences were from Firmicutes and Bacteroidetes spp., respectively. On a genus level, samples from anal fistula patients showed a greater abundance of Prevotella spp. (4.9%±7.4% vs. 0.1%±1.1%, P<0.001), Megamonas (3.9%±8.2% vs. 0.5%±4.2%, P<0.05) and Lachnospira (2.6%±5.7% vs. 0.1%±3.4%, P<0.05), while showing a lesser abundance of Proteobacteria spp. (0.02%±4.2% vs. 9.3%±14.4%, P<0.01), Enterococcus (0.02%±2.3% vs. 9.3%±19.6%, P<0.05), Bacteroides (24.7%±9.9% vs. 29.8%±9.1%, P<0.05) and Klebsiella (0.4%±4.2% vs. 3.9%±7.3%, P<0.05) compared with healthy controls. Intestinal flora diversity in the complex anal fistula group was richer than in controls, as indicated by a higher ACE index (293.30±44.00 vs. 218.75±33.83, t=102.069, P<0.001), a higher Chao index (318.40±41.99 vs. 250.00±46.38, t=77.818, P=0.028), a higher Shannon index (3.36±0.29 vs. 2.43±0.34, t=9.657, P=0.001), and a lower Simpson index (0.103±0.013 vs. 0.131±0.013, t=5.551, P=0.046). LDA effect size analysis suggests that the main strains of Veillonellaceae, Selenemondales and Negativicutes, which all belong to the phylum Firmicutes, have the greatest influence on the above difference (LDA>4). Conclusions: The diversity of intestinal flora in patients with complex anal fistula is greater than in healthy controls, suggesting that these bacteria or their metabolites may be involved in the occurrence and development of anal fistulas.
Anti-Bacterial Agents ; Bacteria/genetics* ; DNA, Ribosomal ; Gastrointestinal Microbiome ; Humans ; RNA, Ribosomal, 16S/genetics* ; Rectal Fistula/surgery*

OBJECTIVES: To study the difference in intestinal flora between children with focal epilepsy and healthy children and the change in intestinal flora after treatment in children with epilepsy. METHODS: A total of 10 children with newly diagnosed focal epilepsy were recruited as the case group and were all treated with oxcarbazepine alone. Their clinical data were recorded. Fecal specimens before treatment and after 3 months of treatment were collected. Fourteen aged-matched healthy children were recruited as the control group. Total bacterial DNA was extracted from the fecal specimens for 16S rDNA sequencing and bioinformatics analysis. RESULTS: After 3 months of carbamazepine treatment, the seizure frequency was reduced by >50% in the case group. At the phylum level, the abundance of Actinobacteria in the case group before treatment was significantly higher than that in the control group (P<0.05), and it was reduced after treatment (P<0.05). At the genus level, the abundances of Escherichia/Shigella, Streptococcus, Collinsella, and Megamonas in the case group before treatment were significantly higher than those in the control group (P<0.05), and the abundances of these bacteria decreased significantly after treatment (P<0.05). CONCLUSIONS There is a significant difference in intestinal flora between children with focal epilepsy and healthy children. Oxcarbazepine can significantly improve the symptoms and intestinal flora in children with epilepsy.
Aged ; Bacteria/genetics* ; Child ; DNA, Bacterial ; Epilepsies, Partial/drug therapy* ; Gastrointestinal Microbiome ; Humans ; RNA, Ribosomal, 16S/genetics*

The community structure and diversity of the gut microbiota are associated with human diseases. However, the analysis of different community structure might be influenced by experimental approaches such as the quality of DNA extraction. Therefore, evaluating the efficiency of different DNA extraction methods for specific intestinal species is a guideline for obtaining a comprehensive human gut microbial profile, which may assist the in-depth investigation into the structure of the gut microbial community. The aim of this study was to perform a comparative analysis of five different DNA extraction methods. With the aid of qPCR, the efficiency of five DNA extraction kits was evaluated in terms of the purity of the extracted DNA, the DNA concentration, and the abundance of genomic DNA extracted from specific intestinal species. The results showed that the kit Q gave the best extraction results, especially for Gram-positive bacteria such as Lactobacillus and Bifidobacterium. The average DNA concentration of the N kit was lower than that of the Q kit, but there was no significant difference between the two in terms of the purity. Compared to the other three commercial kits (M, PSP, TG), the efficiency of the N kit in extracting the genomic DNA of the specified microorganisms were the least different from those of the Q kit. In contrast, the DNA extracted by the M kit was of higher quality but of lower concentration, and was not very efficient for Gram-positive bacteria. The DNA extracted by the TG and PSP kits was inferior to the other validated kits in terms of the concentration, quality and bacterial abundance. These results provide a basis for the selection of genomic DNA extraction methods in microecological research experiments.
DNA/genetics* ; DNA, Bacterial/genetics* ; Feces/microbiology* ; Humans ; Microbiota/genetics* ; RNA, Ribosomal, 16S/genetics*

Objective: To evaluate multidrug resistant loop-mediated isothermal amplification (MDR-LAMP) assay for the early diagnosis of multidrug-resistant tuberculosis and to compare the mutation patterns associated with the Methods: MDR-LAMP assay was evaluated using 100 Results: The sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of MDR-LAMP were 85.5%, 93.6%, 96.7%, and 74.4% for the detection of resistance to isoniazid and rifampicin, respectively, and 80.5%, 92.3%, 98.6%, and 41.4% for the detection of Conclusion MDR-LAMP is a rapid and accessible assay for the laboratory identification of rifampicin and isoniazid resistance of
Antitubercular Agents ; Bacterial Proteins/genetics* ; Catalase/genetics* ; DNA, Bacterial/analysis* ; DNA-Directed RNA Polymerases/genetics* ; Drug Resistance, Multiple, Bacterial/genetics* ; Isoniazid ; Molecular Diagnostic Techniques/methods* ; Mutation ; Mycobacterium tuberculosis/isolation & purification* ; Nucleic Acid Amplification Techniques/methods* ; Oxidoreductases/genetics* ; Phenotype ; Rifampin ; Whole Genome Sequencing

The purpose of this study is to provide a simple and reliable genetic typing approach for molecular drug susceptibility test of Mycobacterium tuberculosis, through the developing of fluorescence molecular marker of rifampicin resistance gene rpoB. Eleven fluorescent molecular markers of the rpoB gene were established by using the sequence difference between the amino acid positions 531, 526, 516, 511 and 513 of rpoB gene of rifampicin-resistant strains and the alleles of rifampicin-sensitive strains, combined with the PARMS technique (Penta-primer amplification refractory mutation system). We used 104 clinical isolates of Mycobacterium tuberculosis to validate this marker and it was verified by sequencing as 100% correct. These samples were also tested with proportional drug sensitivity test. The coincidence rate was 94.23%. The molecular markers had high reliability for genotyping of rpoB gene. It can also detect low-concentration drug-resistant samples (511/533 unit point mutations) whose phenotypic susceptibility cannot be detected. The eleven sets of fluorescent molecular markers could cover 92%-96% of rpoB gene mutation types of rifampicin-resistant strains, and provide new idea for rapid detection of rifampin-resistant Mycobacterium tuberculosis.
Bacterial Proteins/genetics* ; DNA-Directed RNA Polymerases/genetics* ; Drug Resistance, Bacterial/genetics* ; Microbial Sensitivity Tests ; Mutation ; Mycobacterium tuberculosis/genetics* ; Reproducibility of Results ; Rifampin/pharmacology* ; Technology

Adolescent ; Adult ; Aged ; Aged, 80 and over ; Air Microbiology ; Bacteria/isolation & purification* ; Child ; Child, Preschool ; China/epidemiology* ; DNA, Bacterial/analysis* ; DNA, Ribosomal/analysis* ; Female ; Humans ; Infant ; Infant, Newborn ; Male ; Middle Aged ; Pneumonia, Bacterial/microbiology* ; Risk Assessment/methods* ; Young Adult

To rapidly and accurately manipulate genome such as gene deletion, insertion and site mutation, the whole genome of a very virulent strain Md5 of Marek's disease virus (MDV) was inserted into bacterial artificial chromosome (BAC) through homogeneous recombination. The recombinant DNA was electroporated into DH10B competent cells and identified by PCR and restriction fragment length polymorphism analysis. An infectious clone of Md5BAC was obtained following transfection into chicken embryo fibroblast (CEF) cells. Furthermore, a lorf10 deletion mutant was constructed by two step Red-mediated homologous recombination. To confirm the specific role of gene deletion, the lorf10 was reinserted into the original site of MDV genome to make a revertant strain. All the constructs were rescued by transfection into CEF cells, respectively. The successful packaging of recombinant viruses was confirmed by indirect immunofluorescence assay. The results of growth kinetics assay and plaques area measurement showed that the lorf10 is dispensable for MDV propagation in vitro. Overall, this study successfully constructed an infectious BAC clone of MDV and demonstrated its application in genome manipulation; the knowledge gained from our study could be further applied to other hepesviruses.
Animals ; Chick Embryo ; Chickens ; Chromosomes, Artificial, Bacterial ; DNA, Recombinant ; Herpesvirus 2, Gallid/genetics* ; Marek Disease