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Veterinary Research Communications Feb 2022Tick-borne viruses and bacteria that can cause diseases of animals and humans have high impact and are of concern as significant threats to human health worldwide. In...
Tick-borne viruses and bacteria that can cause diseases of animals and humans have high impact and are of concern as significant threats to human health worldwide. In this research, we screened microorganisms related to those pathogens in ticks from dogs, a cat, and a cow. The techniques used were PCR, DNA sequencing and phylogenetic analysis to detect and classify the microorganisms [Flavivirus, severe fever with thrombocytopenia syndrome virus (SFTSV), Phlebovirus, Coronavirus, Canine Parvovirus, eubacteria, Coxiella and Rickettsia]. A novel virus named Phlebovirus-like-AYUT and Stenotrophomonas maltophilia bacteria were found in one individual tick (Rhipicephalus sanguineus s.l.) from a dog. All tick samples were negative for Rickettsia, while 9/21 (42.9 %) were positive for Coxiella bacteria. The novel virus "Phlebovirus-like-AYUT" (the name derives from Phra Nakhon Si Ayutthaya Province in Thailand) was resolved by phylogenetic analysis of the partial L segment by maximum likelihood (ML) method using MEGA X. The phylogenetic tree also indicated that the virus was related to Phlebovirus in brown dog ticks reported in Trinidad and Tobago. In contrast, Phlebovirus-like-AYUT was in a distinct clade from Lihan tick Phlebovirus-Thailand (LTPV), which was previously found in cow ticks, Rhipicephalus microplus, in Nan Province, Thailand. This study reports the Stenotrophomonas maltophilia bacterium with a novel Phlebovirus-like-AYUT in a brown dog tick. The roles of this bacterium in a virus-positive tick or in viral transmission from animal host requires further investigation.
Topics: Animals; Cattle; Cattle Diseases; Coinfection; Dog Diseases; Dogs; Female; Phlebovirus; Phylogeny; Rhipicephalus sanguineus; Stenotrophomonas maltophilia; Thailand
PubMed: 34725749
DOI: 10.1007/s11259-021-09855-7 -
Infection and Immunity Mar 2020is a Gram-negative bacterium found ubiquitously in the environment that has historically been regarded as nonpathogenic. is increasingly observed in patient sputa in...
is a Gram-negative bacterium found ubiquitously in the environment that has historically been regarded as nonpathogenic. is increasingly observed in patient sputa in cystic fibrosis (CF), and while existing epidemiology indicates that patients with have poorer diagnoses, its clinical significance remains unclear. Moreover, as multidrug resistance is common among isolates, treatment options for these infections may be limited. Here, we investigated the pathogenicity of alone and during polymicrobial infection with Colonization, persistence, and virulence of were assessed in experimental respiratory infections of mice. The results of this study indicate that transiently colonizes the lung accompanied by significant weight loss and immune cell infiltration and the expression of early inflammatory markers, including interleukin 6 (IL-6), IL-1α, and tumor necrosis factor alpha (TNF-α). Importantly, polymicrobial infection with elicited significantly higher counts in bronchoalveolar lavages and lung tissue homogenates. This increase in bacterial load was directly correlated with the density of the population and required viable bacteria. Microscopic analysis of biofilms formed revealed that formed well-integrated biofilms with , and these organisms colocalize in the lung during dual-species infection. Based on these results, we conclude that active cellular processes by afford a significant benefit to during polymicrobial infections. Furthermore, these results indicate that may have clinical significance in respiratory infections.
Topics: Animals; Bacterial Load; Body Weight; Bronchoalveolar Lavage Fluid; Coinfection; Disease Models, Animal; Gram-Negative Bacterial Infections; Immunity, Innate; Lung; Mice; Microbial Interactions; Pneumonia, Bacterial; Pseudomonas aeruginosa; Stenotrophomonas maltophilia
PubMed: 31932329
DOI: 10.1128/IAI.00855-19 -
Microorganisms Dec 2022is an emerging pathogen classified as a public health concern, that infects critically ill patients and has expressed resistance against antimicrobial therapy. The aim...
BACKGROUND
is an emerging pathogen classified as a public health concern, that infects critically ill patients and has expressed resistance against antimicrobial therapy. The aim of this study was to examine the epidemiological pattern, resistance characteristics and clinical outcomes of infections in hospitalized patients.
METHODS
The study included 393 isolates from different clinical specimens as well as the clinical data of 209 Intensive Care Unit (ICU) patients. The patients' data were obtained from medical and laboratory files. Descriptive statistics and a univariate analysis were used to report and compare the demographics, clinical data, and outcomes.
RESULTS
The was mostly isolated from the respiratory specimens of ICU patients. The adult patients were more likely to develop serious infections and worse outcomes than were pediatric patients. The most common co-infecting pathogens were SARS-CoV2 and . The death rate was 44.5% and increased to 47.1% in the case of a respiratory infection. Septic shock was the most significant predictor of mortality. Older age and mechanical ventilation were independent and significant risk factors that worsened the outcomes in patients with respiratory infections.
CONCLUSIONS
The identification of as a threat highlights the importance of surveillance studies in this region.
PubMed: 36557759
DOI: 10.3390/microorganisms10122506 -
Antibiotics (Basel, Switzerland) Oct 2021is an urgent global threat due to its increasing incidence and intrinsic antibiotic resistance. Antibiotic development has focused on carbapenem-resistant... (Review)
Review
is an urgent global threat due to its increasing incidence and intrinsic antibiotic resistance. Antibiotic development has focused on carbapenem-resistant Enterobacteriaceae, Pseudomonas, and Acinetobacter, with approved antibiotics in recent years having limited activity for Stenotrophomonas. Accordingly, novel treatment strategies for Stenotrophomonas are desperately needed. We conducted a systemic literature review and offer recommendations based on current evidence for a treatment strategy of Stenotrophomonas infection.
PubMed: 34680807
DOI: 10.3390/antibiotics10101226 -
Antimicrobial Agents and Chemotherapy Mar 2021Cefiderocol is a novel siderophore cephalosporin antibiotic with broad coverage against difficult-to-treat Gram-negative bacteria, including those resistant to...
Cefiderocol is a novel siderophore cephalosporin antibiotic with broad coverage against difficult-to-treat Gram-negative bacteria, including those resistant to carbapenems. Its activity against was investigated against clinical isolates and in lung infection models using strains either resistant (SR202006) or susceptible (SR201934, SR200614) to trimethoprim-sulfamethoxazole. Cefiderocol demonstrated potent activity against all 217 clinical isolates tested (MIC, 0.063 μg/ml; MIC, 0.25 μg/ml). Cefiderocol also demonstrated low MICs against the trimethoprim-sulfamethoxazole-resistant strains (i.e., SR202006; MIC, 0.125 μg/ml). In a neutropenic mouse lung infection model, cefiderocol (30 mg/kg body weight and 100 mg/kg) demonstrated a significant, dose-dependent reduction in the lung viable bacteria cell count compared with untreated controls in infection and was the only antibiotic tested to show a similar significant effect in a trimethoprim-sulfamethoxazole-resistant infection. In immunocompetent rat lung infection models of , humanized dosing of cefiderocol (2 g every 8 h) and meropenem (1 g every 8 h) revealed pharmacokinetic profiles similar to those in human subjects, and the humanized cefiderocol dosing significantly reduced the lung viable bacteria cell count compared with baseline controls, which received no intervention. Together, the results from these studies suggest that cefiderocol could provide an effective alternative treatment option for infections in the lower respiratory tract, particularly strains resistant to empirical antibiotics, such as trimethoprim-sulfamethoxazole or minocycline.
Topics: Animals; Anti-Bacterial Agents; Cephalosporins; Drug Resistance, Multiple, Bacterial; Gram-Negative Bacteria; Gram-Negative Bacterial Infections; Microbial Sensitivity Tests; Rats; Stenotrophomonas maltophilia; Cefiderocol
PubMed: 33526491
DOI: 10.1128/AAC.01436-20 -
Polish Journal of Microbiology Sep 2023This work investigated the genetic relationship among strains in fecal samples from dairy cows in northeast China and identified the dominant β-lactamase genotype. One...
This work investigated the genetic relationship among strains in fecal samples from dairy cows in northeast China and identified the dominant β-lactamase genotype. One hundred and six samples were collected from two randomly selected cow farms in northeast China, and the isolates were identified with MALDI-TOF/MS. Whole-genome sequencing was conducted using Illumina HiSeq 4000-PE150 platform (Illumina, Inc., USA). The antimicrobial resistance genes were detected using CGE services. The phylogenetic analysis of strains was performed by Roary and MEGA X. In total, 24 isolates were isolated. The results of resistome analysis showed all strains carrying gene, which was the only β-lactamase genotype. In addition, the aminoglycoside resistance genes and were found. The phylogenetic tree indicated the clonal diversity of in these two regions and the clonal relatedness of the strains from these regions. This study first investigated the dissemination and characterization of isolates from dairy cows in northeast China and provided evidence of the potential transmission between two provinces. Furthermore, it indicated was the most prevalent genotype of β-lactamase in these regions.
Topics: Animals; Female; Cattle; Stenotrophomonas maltophilia; Phylogeny; China; Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; beta-Lactamases
PubMed: 37725894
DOI: 10.33073/pjm-2023-032 -
Iranian Journal of Microbiology Apr 2024is an opportunistic pathogen causing nosocomial infections. Diclofenac is an anti-inflammatory drug that is considered a non-antibiotic drug. This study assessed the...
BACKGROUND AND OBJECTIVES
is an opportunistic pathogen causing nosocomial infections. Diclofenac is an anti-inflammatory drug that is considered a non-antibiotic drug. This study assessed the antibacterial and antibiofilm effects of diclofenac and levofloxacin/diclofenac combination against levofloxacin resistant isolates.
MATERIALS AND METHODS
Minimum inhibitory concentration was determined using broth microdilution method for levofloxacin, diclofenac, and levofloxacin/diclofenac combination. Biofilm forming capacity and biofilm inhibition assay were determined. Relative gene expression was measured for efflux pump genes; , and genes and biofilm related genes , and without and with diclofenac and the combination.
RESULTS
Diclofenac demonstrated MIC of 1 mg/ml. The combination-with ½ MIC diclofenac-showed synergism where levofloxacin MIC undergone 16-32 fold decrease. All the isolates that overexpressed and showed a significant decrease in gene expression in presence of diclofenac or the combination. The mean percentage inhibition of biofilm formation with diclofenac and the combination was 40.59% and 46.49%, respectively. This agreed with biofilm related genes expression investigations.
CONCLUSION
Diclofenac showed an antibacterial effect against The combination showed synergism, significant reduction in biofilm formation and in the relative level of gene expression. Furthermore, it can potentiate the levofloxacin activity or revert its resistance.
PubMed: 38854979
DOI: 10.18502/ijm.v16i2.15349 -
Research in Microbiology 2022Maltocin P28, produced by Stenotrophomonas maltophilia P28, is an R-type phage tail-like bacteriocin (PTLB). Its gene cluster consists of 23 putative genes, including...
Maltocin P28, produced by Stenotrophomonas maltophilia P28, is an R-type phage tail-like bacteriocin (PTLB). Its gene cluster consists of 23 putative genes, including nine nonstructural genes and fourteen structural genes. In this work, three nonstructural genes, mpsA, mpsH and mpsR, were found to encode transcriptional regulators to control maltocin P28 synthesis. MpsA activated the transcription of mpsH and lysis genes. MpsH activated the transcription of structural genes. Under normal growth conditions, MpsR repressed the transcription of mpsA and the structural genes, as well as its own. When S. maltophilia P28 was treated with mitomycin C, an immediate and significant decrease in the amount of MpsR was observed, followed by derepressed expression of mpsA, mpsR and structural genes, a marked rise in the expression of all regulatory and structural genes, and finally a clear increase in the maltocin P28 production. Neither the recA gene nor the lexA gene was found to be involved in the induced synthesis of maltocin P28. Our study indicated that a unique mechanism regulates the expression of maltocin genes in S. maltophilia, representing a novel strategy for balancing the expression of PTLB genes in bacteria.
Topics: Bacteriocins; Multigene Family; Stenotrophomonas maltophilia
PubMed: 35569725
DOI: 10.1016/j.resmic.2022.103956 -
Frontiers in Microbiology 2023is an opportunistic pathogen infecting persons with cystic fibrosis (pwCF) and portends a worse prognosis. Studies of infection dynamics have been limited by cohort...
INTRODUCTION
is an opportunistic pathogen infecting persons with cystic fibrosis (pwCF) and portends a worse prognosis. Studies of infection dynamics have been limited by cohort size and follow-up. We investigated the natural history, transmission potential, and evolution of in a large Canadian cohort of 321 pwCF over a 37-year period.
METHODS
One-hundred sixty-two isolates from 74 pwCF (23%) were typed by pulsed-field gel electrophoresis, and shared pulsotypes underwent whole-genome sequencing.
RESULTS
was recovered at least once in 82 pwCF (25.5%). Sixty-four pwCF were infected by unique pulsotypes, but shared pulsotypes were observed between 10 pwCF. In chronic carriage, longer time periods between positive sputum cultures increased the likelihood that subsequent isolates were unrelated. Isolates from individual pwCF were largely clonal, with differences in gene content being the primary source of genetic diversity objectified by gene content differences. Disproportionate progression of CF lung disease was not observed amongst those infected with multiple strains over time (versus a single) or amongst those with shared clones (versus strains only infecting one patient). We did not observe evidence of patient-to-patient transmission despite relatedness between isolates. Twenty-four genes with ≥ 2 mutations accumulated over time were identified across 42 sequenced isolates from all 11 pwCF with ≥ 2 sequenced isolates, suggesting a potential role for these genes in adaptation of to the CF lung.
DISCUSSION
Genomic analyses suggested common, indirect sources as the origins of infections in the clinic population. The information derived from a genomics-based understanding of the natural history of infection within CF provides unique insight into its potential for in-host evolution.
PubMed: 37396351
DOI: 10.3389/fmicb.2023.1205389 -
Antimicrobial Agents and Chemotherapy Apr 2022Pathogenic bacteria experience diverse stresses induced by host cells during infection and have developed intricate systems to trigger appropriate responses. Bacterial...
Pathogenic bacteria experience diverse stresses induced by host cells during infection and have developed intricate systems to trigger appropriate responses. Bacterial stress responses have been reported to defend against these stresses and cross-protect bacteria from antibiotic attack. In this study, we aimed to assess whether oxidative stress affects bacterial susceptibility to fluoroquinolone (FQ) and the underlying mechanism. Stenotrophomonas maltophilia, a species with high genetic diversity, is distributed ubiquitously and is an emerging multidrug-resistant opportunistic pathogen. FQs are among the limited antibiotic treatment options for S. maltophilia infection. The minimum inhibitory concentrations (MICs) of 103 S. maltophilia clinical isolates against ciprofloxacin (CIP) and levofloxacin (LVX) were determined using the agar dilution method in Mueller-Hinton plates with or without menadione (MD), a superoxide generator. The resistance rates for ciprofloxacin and levofloxacin were 40% and 18% in the MD-null group and increased to 91% and 23%, respectively, in the MD-treated group. Of the 103 isolates tested, 54% and 27% had elevated MICs against ciprofloxacin and levofloxacin, respectively, in the presence of MD. The involvement of oxidative stress responses in the MD-mediated FQ resistance was further assessed by mutants construction and viability assay. Among the 16 oxidative stress alleviation systems evaluated, and contributed to MD-mediated FQ resistance. The antibiotic susceptibility test is an accredited clinical method to evaluate bacterial susceptibility to antibiotics in clinical practice. However, oxidative stress-mediated antibiotic resistance was not detected using this test, which may lead to treatment failure.
Topics: Anti-Bacterial Agents; Ciprofloxacin; Fluoroquinolones; Gram-Negative Bacterial Infections; Humans; Levofloxacin; Microbial Sensitivity Tests; Oxidative Stress; Stenotrophomonas maltophilia
PubMed: 35285252
DOI: 10.1128/aac.02043-21