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BMC Genomics Sep 2023Haemorrhagic septicaemia (HS) is a highly fatal and predominant disease in livestock, particularly cattle and buffalo in the tropical regions of the world. Pasteurella...
BACKGROUND
Haemorrhagic septicaemia (HS) is a highly fatal and predominant disease in livestock, particularly cattle and buffalo in the tropical regions of the world. Pasteurella multocida (P. multocida), serotypes B:2 and E:2, are reported to be the main causes of HS wherein serotype B:2 is more common in Asian countries including Pakistan and costs heavy financial losses every year. As yet, very little molecular and genomic information related to the HS-associated serotypes of P. multocida isolated from Pakistan is available. Therefore, this study aimed to explore the characteristics of novel bovine isolates of P. multocida serotype B:2 at the genomic level and perform comparative genomic analysis of various P. multocida strains from Pakistan to better understand the genetic basis of pathogenesis and virulence.
RESULTS
To understand the genomic variability and pathogenomics, we characterized three HS-associated P. multocida serotype B:2 strains isolated from the Faisalabad (PM1), Peshawar (PM2) and Okara (PM3) districts of Punjab, Pakistan. Together with the other nine publicly available Pakistani-origin P. multocida strains and a reference strain Pm70, a comparative genomic analysis was performed. The sequenced strains were characterized as serotype B and belong to ST-122. The strains contain no plasmids; however, each strain contains at least two complete prophages. The pan-genome analysis revealed a higher number of core genes indicating a close resemblance to the studied genomes and very few genes (1%) of the core genome serve as a part of virulence, disease, and defense mechanisms. We further identified that studied P. multocida B:2 strains harbor common antibiotic resistance genes, specifically PBP3 and EF-Tu. Remarkably, the distribution of virulence factors revealed that OmpH and plpE were not present in any P. multocida B:2 strains while the presence of these antigens was reported uniformly in all serotypes of P. multocida.
CONCLUSION
This study's findings indicate the absence of OmpH and PlpE in the analyzed P. multocida B:2 strains, which are known surface antigens and provide protective immunity against P. multocida infection. The availability of additional genomic data on P. multocida B:2 strains from Pakistan will facilitate the development of localized therapeutic agents and rapid diagnostic tools specifically targeting HS-associated P. multocida B:2 strains.
Topics: Animals; Cattle; Pakistan; Pasteurella multocida; Serogroup; Hemorrhagic Septicemia; Genomics; Buffaloes
PubMed: 37710174
DOI: 10.1186/s12864-023-09626-5 -
Frontiers in Microbiology 2023Extracellular vesicle (EV) production by bacteria is an important mechanism for microbial communication and host-pathogen interaction. EVs of some bacterial species have...
Extracellular vesicle (EV) production by bacteria is an important mechanism for microbial communication and host-pathogen interaction. EVs of some bacterial species have been reported to contain nucleic acids. However, the role of small RNAs (sRNAs) packaged in EVs is poorly understood. Here, we report on the RNA cargo of EVs produced by the pig pathogen , the causal agent of porcine pleuropneumonia, a disease which causes substantial economic losses to the swine industry worldwide. The EVs produced by aerobically and anaerobically grown bacteria were only slightly different in size and distribution. Total cell and outer membrane protein profiles and lipid composition of whole cell extracts and EVs were similar, although EVs contained rough lipopolysaccharide compared to the smooth form in whole cells. Approximately 50% of larvae died after the injection of EVs. RNAseq, RT-PCR, protection from nuclease degradation, and database searching identified previously described and 13 novel sRNAs in EVs, some of which were enriched compared to whole cell content. We conclude that EVs contain sRNAs, including those known to be involved in virulence, and some with homologs in other and/or non-. Further work will establish whether the novel sRNAs in EVs play any role in pathogenesis.
PubMed: 38075857
DOI: 10.3389/fmicb.2023.1291930 -
International Journal of Antimicrobial... Nov 2023Haemophilus parainfluenzae is a commensal organism with rising numbers of multidrug-resistant (MDR) strains. This pathogen is of increasing clinical relevance in...
Haemophilus parainfluenzae is a commensal organism with rising numbers of multidrug-resistant (MDR) strains. This pathogen is of increasing clinical relevance in urogenital infection. The aim of this work was to identify and characterise the molecular mechanisms of resistance associated with four cephalosporin-resistant H. parainfluenzae strains collected from patients with urethritis. Antimicrobial resistance was determined by microdilution following European Committee on Antimicrobial Susceptibility Testing criteria. Strains were then analysed by whole-genome sequencing to determine clonal relationship and the molecular basis of antimicrobial resistance. Finally, a phylogenetic analysis was performed on all urogenital MDR strains of H. parainfluenzae previously isolated in our hospital. All strains were resistant to β-lactams, macrolides, tetracycline, fluoroquinolones, chloramphenicol, cotrimoxazole, and aminoglycosides. The resistance profile was compatible with the presence of an extended-spectrum β-lactamase (ESBL). Whole-genome sequencing detected bla that conferred high minimum inhibitory concentrations to cephalosporins in two novel integrative and conjugative elements (ICEHpaHUB6 and ICEHpaHUB7) that also harboured a bla β-lactamase. This study shows a novel bla ESBL carried in an integrative conjugative element in four extensively drug-resistant H. parainfluenzae strains. This resistance determinant could be transmitted to other sexually transmitted pathogens and this is a cause for concern.
Topics: Humans; Haemophilus parainfluenzae; Urethritis; Phylogeny; Anti-Bacterial Agents; Cephalosporins; beta-Lactamases; Microbial Sensitivity Tests
PubMed: 37774891
DOI: 10.1016/j.ijantimicag.2023.106991 -
Frontiers in Cellular and Infection... 2023Today, metagenomic next-generation sequencing (mNGS) has emerged as a diagnostic tool for infections. However, since Hainan has a complicated pathogen spectrum, the...
Clinical utility of metagenomic next-generation sequencing in pathogen detection for lower respiratory tract infections and impact on clinical outcomes in southernmost China.
BACKGROUND
Today, metagenomic next-generation sequencing (mNGS) has emerged as a diagnostic tool for infections. However, since Hainan has a complicated pathogen spectrum, the diagnostic value and impact on patient outcomes of mNGS in Hainan are to be explored.
METHODS
From April 2020 to October 2021, 266 suspected lower respiratory tract infections (LRTIs) patients in Hainan were enrolled, and specimens were collected before antibiotic treatment. Bronchoalveolar lavage fluid (BALF) samples were subjected to mNGS and culture to compare the diagnostic performance. Other conventional microbiological tests (CMT) were also performed. Patients' treatments and clinical outcomes were recorded, and the antibiotic resistance genes (ARGs) were detected via mNGS workflow.
RESULTS
The positive rate of mNGS outperformed that of culture (87.55% vs. 39.30%, <0.001) and CMT (87.12% vs. 52.65%, <0.001). Specifically, mNGS detected more (12.03% vs 9.02%, <0.05), (9.77% vs 2.26%, <0.001), (3.00% vs 0.75%, <0.05), (26.32% vs 7.52%, <0.001) and uncommon pathogens. It also demonstrated great diagnostic advantages in with 80% sensitivity and 97.4% specificity. Over half of the patients (147, 55.26%) had modified empirical treatment according to mNGS results and 89.12% of them responded well. For three deaths with modified treatment, multiple drug resistance was predicted by mNGS and confirmed by antibiotic susceptibility test.
CONCLUSIONS
The application of mNGS can benefit clinics in pathogen identification and antimicrobial treatment stewardship. Physicians should be alert to some emerging uncommon pathogens, including , and rare NTM.
Topics: Humans; High-Throughput Nucleotide Sequencing; Anti-Bacterial Agents; Antimicrobial Stewardship; China; Haemophilus influenzae; Metagenomics; Respiratory Tract Infections; Sensitivity and Specificity
PubMed: 38145053
DOI: 10.3389/fcimb.2023.1271952 -
Avian Pathology : Journal of the W.V.P.A Oct 2023is the aetiological agent of infectious coryza (IC) in chickens and characterized by acute respiratory distress and severe drop in egg production. Vaccination is...
is the aetiological agent of infectious coryza (IC) in chickens and characterized by acute respiratory distress and severe drop in egg production. Vaccination is important in the control of IC outbreaks and the efficacy of vaccination is dependent on serovars included in the vaccine. Classical serotyping of is laborious and hampered by poor availability of antigens and antisera. The haemagglutinin, important in classical serotyping, is encoded by the gene. gene analysis has been shown to have potential as alternative to classical serotyping. The aim of the present study was to further investigate the potential of sequence analyses of partial region 1 of the gene, the hypervariable region and the concatenated sequences of both fragments. For this analysis, 123 gene sequences (field isolates, serovar reference strains and vaccine strains) were included. Evaluation of serovar references and vaccine strains revealed a need for critical evaluation, especially within Page serovar B and C. Phylogenetic analysis of region 1 resulted in a separation of Page serovar A, B and C strains. Analysis of the HVR alone was not sufficient to discriminate all nine different Kume serovar references. The concatenated sequences of region 1 and HVR resulted in 14 clusters with a high correlation with Page serovar and with the nine currently known Kume serovars and is therefore proposed as a novel genotyping method that could be used as an alternative for classical serotyping of .
Topics: Animals; Serotyping; Haemophilus Infections; Genotype; Phylogeny; Chickens; Haemophilus paragallinarum; Poultry Diseases
PubMed: 37470411
DOI: 10.1080/03079457.2023.2239178 -
BMC Veterinary Research Apr 2024Gamithromycin is an effective therapy for bovine and swine respiratory diseases but not utilized for rabbits. Given its potent activity against respiratory pathogens, we...
BACKGROUND
Gamithromycin is an effective therapy for bovine and swine respiratory diseases but not utilized for rabbits. Given its potent activity against respiratory pathogens, we sought to determine the pharmacokinetic profiles, antimicrobial activity and target pharmacokinetic/pharmacodynamic (PK/PD) exposures associated with therapeutic effect of gamithromycin against Pasteurella multocida in rabbits.
RESULTS
Gamithromycin showed favorable PK properties in rabbits, including high subcutaneous bioavailability (86.7 ± 10.7%) and low plasma protein binding (18.5-31.9%). PK analysis identified a mean plasma peak concentration (C) of 1.64 ± 0.86 mg/L and terminal half-life (T) of 31.5 ± 5.74 h after subcutaneous injection. For P. multocida, short post-antibiotic effects (PAE) (1.1-5.3 h) and post-antibiotic sub-inhibitory concentration effects (PA-SME) (6.6-9.1 h) were observed after exposure to gamithromycin at 1 to 4× minimal inhibitory concentration (MIC). Gamithromycin demonstrated concentration-dependent bactericidal activity and the PK/PD index area under the concentration-time curve over 24 h (AUC)/MIC correlated well with efficacy (R > 0.99). The plasma AUC/MIC ratios of gamithromycin associated with the bacteriostatic, bactericidal and bacterial eradication against P. multocida were 15.4, 24.9 and 27.8 h in rabbits, respectively.
CONCLUSIONS
Subcutaneous administration of 6 mg/kg gamithromycin reached therapeutic concentrations in rabbit plasma against P. multocida. The PK/PD ratios determined herein in combination with ex vivo activity and favorable rabbit PK indicate that gamithromycin may be used for the treatment of rabbit pasteurellosis.
Topics: Rabbits; Animals; Cattle; Swine; Anti-Bacterial Agents; Pasteurella Infections; Macrolides; Pasteurella multocida; Lagomorpha; Microbial Sensitivity Tests; Cattle Diseases; Swine Diseases
PubMed: 38643185
DOI: 10.1186/s12917-024-03988-y -
International Dental Journal Feb 2024The aim of this work was to explore the association between Aggregatibacter actinomycetemcomitans (A actinomycetemcomitans) infection and disease activity amongst those...
OBJECTIVE
The aim of this work was to explore the association between Aggregatibacter actinomycetemcomitans (A actinomycetemcomitans) infection and disease activity amongst those with rheumatoid arthritis (RA) with or without periodontitis (PD) in a Chinese population.
METHODS
A case-control study was conducted from November 2017 to March 2019. The correlation coefficients between A actinomycetemcomitans positivity and RA-related examination indicators as well as periodontal examination parameters were calculated by using the Spearman correlation analysis.
RESULTS
A total of 115 patients with RA were recruited: 67 patients with RA only and 48 with RA + PD. The percentage of A actinomycetemcomitans positivity was significantly higher in the RA + PD group compared with the RA-only group (P = .007 for positive percentage; P = .020 for percentage of A actinomycetemcomitans positivity in the total oral microbiome). Furthermore, RA-related measures such as Disease Activity Score 28, rheumatoid factor, anticyclic citrullinated peptide, and anticitrullinated protein antibodies were all positively correlated with the percentage of A actinomycetemcomitans positivity (P range: .002∼.041). In addition, significant correlations were observed amongst A actinomycetemcomitans positivity and probing pocket depth (P = .027) and gingival index (P = .043), whereas null correlations were found amongst the percentage of A actinomycetemcomitans positivity and plaque index (P = .344), clinical attachment loss (P = .217), and bleeding on probing (P = .710).
CONCLUSIONS
A actinomycetemcomitans infection may be related to the development of PD amongst patients with RA.
Topics: Humans; Aggregatibacter actinomycetemcomitans; Case-Control Studies; Periodontitis; Arthritis, Rheumatoid; Periodontal Attachment Loss
PubMed: 37517936
DOI: 10.1016/j.identj.2023.06.011 -
Journal of Clinical Periodontology Aug 2023To explore whether adjunctive antibiotics can relevantly influence long-term microbiota changes in stage III-IV periodontitis patients. (Randomized Controlled Trial)
Randomized Controlled Trial
Long-term changes in the subgingival microbiota in patients with stage III-IV periodontitis treated by mechanical therapy and adjunctive systemic antibiotics: A secondary analysis of a randomized controlled trial.
AIM
To explore whether adjunctive antibiotics can relevantly influence long-term microbiota changes in stage III-IV periodontitis patients.
MATERIALS AND METHODS
This is a secondary analysis of a randomized clinical trial on periodontal therapy with adjunctive 500 mg amoxicillin and 400 mg metronidazole or placebo thrice daily for 7 days. Subgingival plaque samples were taken before and 2, 8, 14 and 26 months after mechanical therapy. The V4-hypervariable region of the 16S rRNA gene was sequenced with Illumina MiSeq 250 base pair paired-end reads. Changes at the ribosomal sequence variant (RSV) level, diversity and subgingival-microbial dysbiosis index (SMDI) were explored with a negative binomial regression model and non-parametric tests.
RESULTS
Overall, 50.2% of all raw reads summed up to 72 RSVs (3.0%) that were generated from 163 stage III-IV periodontitis patients. Of those, 16 RSVs, including Porphyromonas gingivalis, Tannerella forsythia and Aggregatibacter actinomycetemcomitans, changed significantly over 26 months because of adjunctive systemic antibiotics. SMDI decreased significantly more in the antibiotic group at all timepoints, whereas the 2-month differences in alpha and beta diversity between groups were not significant at 8 and 14 months, respectively.
CONCLUSIONS
Mechanical periodontal therapy with adjunctive antibiotics induced a relevant and long-term sustainable change towards an oral microbiome more associated with oral health.
Topics: Humans; Anti-Bacterial Agents; RNA, Ribosomal, 16S; Periodontitis; Amoxicillin; Metronidazole; Porphyromonas gingivalis; Microbiota; Aggregatibacter actinomycetemcomitans
PubMed: 37160709
DOI: 10.1111/jcpe.13824 -
Journal of Hazardous Materials Oct 2023In previous studies, 6:2 chlorinated polyfluorinated ether sulfonic acid (6:2 Cl-PFESA), a perfluorooctanesulfonate alternative, has been demonstrated to be toxic to...
In previous studies, 6:2 chlorinated polyfluorinated ether sulfonic acid (6:2 Cl-PFESA), a perfluorooctanesulfonate alternative, has been demonstrated to be toxic to mammals. However, the toxic mechanism of 6:2 Cl-PFESA in mammals is unknown. Herein, adolescent male rats were administered 50 μg/kg/Day 6:2 Cl-PFESA for 28 days (oral gavage) to estimate the toxicity of 6:2 Cl-PFESA and investigate its toxic mechanism. Significant changes in some hematological indicators (e.g., aspartate transaminase and neutrophils) and liver sections (inflammatory cell infiltration) indicated that 6:2 Cl-PFESA exposure caused rat hepatotoxicity. Six steroid hormones (e.g., testosterone, progesterone, and cortisol) in serum and thirteen genes in testicles (related to the pathway of steroid hormone biosynthesis) were significantly regulated in 6:2 Cl-PFESA-treated rats. This suggested that 6:2 Cl-PFESA induced rat endocrine disorders. Compared to the controls, the mean relative abundance of Ruminococcaceae, Pasteurellaceae, Micrococcaceae, and Desulfovibrionaceae was significantly regulated by 1.3-, 0.40-, 0.32-, and 3.2-fold in the 6:2 Cl-PFESA rats, respectively. The 6:2 Cl-PFESA treatment also significantly disturbed 47 gut metabolites (29 upregulated and 18 downregulated), mainly bile acids, short-chain fatty acids, and amino acids. In summary, 6:2 Cl-PFESA induced endocrine disorders and liver inflammation in rats by altering the gut microbiota-gut-testis/liver axis. This study first reveals the toxic mechanism of 6:2 Cl-PFESA in mammals through a multiomics approach and provides comprehensive insight into the toxic mechanism of 6:2 Cl-PFESA.
Topics: Male; Rats; Animals; Testis; Gastrointestinal Microbiome; Alkanesulfonic Acids; Sulfonic Acids; Liver; Fluorocarbons; Inflammation; Mammals
PubMed: 37517236
DOI: 10.1016/j.jhazmat.2023.132155 -
Deutsches Arzteblatt International Feb 2024In late 2022, health care institutions in Germany reported an unusual number of severe, invasive bacterial infections in association with a high incidence of viral... (Observational Study)
Observational Study
BACKGROUND
In late 2022, health care institutions in Germany reported an unusual number of severe, invasive bacterial infections in association with a high incidence of viral respiratory infections.
METHODS
We analyzed routine data on invasive infections due to Haemophilus influenzae, Neisseria meningitidis, Staphylococcus aureus, Streptococcus pneumoniae, and Streptococcus pyogenes (2017-2023) from a voluntary, laboratory-based surveillance system involving continuously participating facilities providing diagnostic routine data that cover approximately one-third of the German population.
RESULTS
In the first quarter (Q1) of 2023, the number of invasive S. pyogenes isolates rose by 142% (n = 837 vs. mean Q1/2017-2019 = 346, 95% CI [258; 434]), while the number of H. influenzae isolates rose by 90% (n = 209 in Q1/2023 vs. mean Q1/2017-2019 = 110, 95% CI [79; 142]), compared to pre-pandemic seasonal peak values. The number of invasive S. pneumoniae isolates was high in two quarters (n = 1732 in Q4/2022 und Q1/2023). Adults aged 55 and older and children younger than 5 years were most affected by invasive H. influenzae, S. pneumoniae, and S. pyogenes infections. N. meningitidis was most commonly found in children under age 5.
CONCLUSION
The reason for the marked rise in invasive bacterial infections may be an increased circulation of respiratory pathogens and elevated susceptibility in the population after relaxation of the measures taken to prevent COVID-19 infection. Coinfections with respiratory viruses may have reinforced this effect. We recommend continuous surveillance, preventive measures such as raising awareness about invasive bacterial diseases, and vaccination as recommended by the German Standing Committee on Vaccinations (STIKO).
Topics: Adult; Child; Humans; Bacterial Infections; Streptococcus pneumoniae; Neisseria meningitidis; Haemophilus influenzae; Staphylococcal Infections; Streptococcus pyogenes; Respiratory Tract Infections; Anti-Bacterial Agents
PubMed: 38229497
DOI: 10.3238/arztebl.m2023.0261