ABSTRACT
Objective: To explore the composition of bacteria in lower respiratory tract of patients with pneumoconiosis and dust exposure, and to compare and analyze the difference and correlation between them. Methods: From May 2020 to January 2021, a prospective multicenter cross-sectional study was conducted to select patients with pneumoconiosis who underwent bronchoalveolar lavage treatment at the Respiratory and Critical Care Medical Department of the 920th Hospital of the Joint Support Force and the Respiratory Department of Tongren Hospital in Kunming, as well as the population of dust recipients. A total of 24 patients with pneumoconiosis (pneumoconiosis group) were included, and 16 dust exposed individuals (dust exposed group) were used as controls. Two groups of patients' alveolar lavage fluid were collected. The 16SrRNA gene V3-V4 sequencing technology and bioinformatics analysis platform were used to measure and analyze the differences in microbial structure composition and associations between bacterial communities. Results: Compared with the dust exposed group, the top 5 bacterial phyla in the alveolar lavage fluid level of patients with pneumoconiosis were the same, followed by Proteobacteria, Firmicutes, Bacteroidetes, Fusobacteria, and Actinobacteria. Compared with the dust exposure group, the pneumoconiosis group patients belong to the top 5 genera of horizontal flora abundance, which are different. The dust exposure group is respectively: Pseudomonas, Proctor, Streptococcus, Achromobacter, and Neisseria. The pneumoconiosis group is respectively: Pseudomonas, Achromobacter, Streptococcus, Ralstonia, and Proctor. The Alpha diversity analysis results showed that compared with the dust exposed group, the level of bacterial diversity in the pneumoconiosis group was difference (P<0.05), and there was no statistically significant difference in bacterial evenness (P>0.05) ; Beta diversity showed differences in microbial community structure between the two groups (P<0.05 ). Single factor microbial association network analysis showed that there was a high correlation between Firmicutes and Bacteroidetes in the pneumoconiosis and dust exposed groups and other species, showing a positive correlation; The correlation between Proteobacteria and other species is high, showing a negative correlation. Conclusion: The structure and relative abundance of bacteria in lower respiratory tract were different between patients with pneumoconiosis and dust exposure, and the diversity of bacteria in lower respiratory tract increased in patients with pneumoconiosis, which may be related to disease status.
Subject(s)
Humans , Cross-Sectional Studies , Prospective Studies , Pneumoconiosis , Bacteria/genetics , Dust , Respiratory SystemABSTRACT
A distinct strain named Micromonospora sp. Rc5 was isolated from Sinai desert of Egypt and recorded high antagonistic activities against some food and bloodborne pathogens. Morphological and chemotaxonomy characterization confirmed that this isolate belongs to genus Micromonospora. Sequencing of partial 16S rDNA and BLASTN showed that isolate Rc5 is identical to Micromonospora haikouensis (99%) but with low bootstrap value in NJ phylogenetic tree. Comprehensive optimization of several growth factors was performed including initial pH, incubation periods, and different sources of carbon and nitrogen. The highest yield of antimicrobial agent production was obtained after 8 days of incubation at 30°C, pH 6.0, 3 x 105CFU/ml in soya bean meal broth media with agitation of 150 rpm. A dramatic proportional decrease occurred with 0.3, 0.6, 0.9 µg active fraction /ml against Staphylococcus aureus culture and reached to complete inhibition at a minimum inhibitory concentration of (1.5 µg /ml). The physicochemical characterization of the purified fraction was identified as phthalate derivative. Our results indicated that Rc5 generated potential antimicrobial compounds against foodborne pathogens and may combat resistant strains of Staphylococcus aureus.
ABSTRACT
The objective of this study was to describe the first report involving a case of equine acute myonecrosis caused by C. novyi type A with an emphasis on clinical signs, the pathological and bacteriological analysis, and molecular identification of the microorganisms as the key of the definitive diagnosis.
Subject(s)
Animals , Clostridium Infections/veterinary , Clostridium/classification , Clostridium/isolation & purification , Horse Diseases/diagnosis , Horse Diseases/pathology , Myositis/veterinary , Necrosis/veterinary , Cluster Analysis , Clostridium Infections/diagnosis , Clostridium Infections/microbiology , Clostridium Infections/pathology , DNA, Bacterial/chemistry , DNA, Bacterial/genetics , DNA, Ribosomal/chemistry , DNA, Ribosomal/genetics , Histocytochemistry , Horses , Horse Diseases/microbiology , Myositis/diagnosis , Myositis/microbiology , Myositis/pathology , Necrosis/diagnosis , Necrosis/microbiology , Necrosis/pathology , Phylogeny , /genetics , Sequence Analysis, DNAABSTRACT
We report a case of cavitary pneumonia caused by N. otitidiscaviarum in a man with diabetes mellitus and thrombocytopenia treated with systemic corticosteroid. Taxonomic identification involved phenotypic testing and molecular identification that was carried out by DNA sequencing of the 16SrRNA gene.