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Tropical Biomedicine Jun 2019A study was conducted for the examination of bacterial species isolated in dogs from Animal Clinics of Nanjing Agricultural University, China. Forty nasal swabs were...
A study was conducted for the examination of bacterial species isolated in dogs from Animal Clinics of Nanjing Agricultural University, China. Forty nasal swabs were taken from dogs having respiratory signs. Staphylococcus pseudintermedius was the most frequently isolated pathogen (37.50 %) followed by Staphylococcus aureus (18.75%), Streptococcus pluranimalium (10.93%), Streptococcus canis (9.37%), Staphylococcus schleiferi (9.37%), Staphylococcus intermedius (6.25%), Staphylococcus cohnii (4.71%) and Staphylococcus hominis (3.12%). S. pseudintermedius and S. pluranimalium were subjected to commonly used antibiotics for determination of resistant drugs. Antimicrobial resistance in S. pseudintermedius was common in gentamicin (70.83%) and tetracycline (50%) while in S. pluranimalium was common in enrofloxacin (71.42%) and gentamicin (57.14%).
PubMed: 33597408
DOI: No ID Found -
Molecules (Basel, Switzerland) Apr 2022Dairy mastitis is a disease of dairy cattle caused by a variety of pathogenic microorganisms which has biought huge economic losses aused huge economic losses to the...
Dairy mastitis is a disease of dairy cattle caused by a variety of pathogenic microorganisms which has biought huge economic losses aused huge economic losses to the world. In this paper, Harmine derivatives and tetrahydro-β-carboline derivatives synthesized by the splice method are shown to have a good inhibitory effect on the pathogenic bacteria of dairy mastitis. The results of a bacteriostatic test on pathogenic bacteria of dairy cow mastitis (, , and ) showed that compound had the best bacteriostatic effect on , with a mic value of 43.7 μ g/mL. When the concentration of was 1 × MIC and 2 × MIC, it had a significant inhibitory effect on , and there was almost no growth of at 4 × MIC. The binding properties of target compound to protein were simulated by the molecular docking technique. The ligand achieved strong binding with the receptor through three hydrogen bonds. The hydrogen bonds were amino acid residues thr-52, arg-51 and ser-24, which are the main force for the compound to bind to active sites.
Topics: Animals; Anti-Bacterial Agents; Carbolines; Cattle; Female; Harmine; Humans; Mastitis, Bovine; Molecular Docking Simulation; Streptococcus
PubMed: 35566239
DOI: 10.3390/molecules27092888 -
Animals : An Open Access Journal From... Jul 2023Studies of microbiota in normal canine milk from healthy dams are sparse. As is the case with blood and urine, it was considered that milk contains no microbiota. Any...
Studies of microbiota in normal canine milk from healthy dams are sparse. As is the case with blood and urine, it was considered that milk contains no microbiota. Any discovery of bacteria in canine milk is, therefore, often noted to be a result of contamination during sampling or interpreted as mastitis and treated with antibiotics. Milk was collected twice within 19 days after natural parturition from 11 lactating dams, with no general or local clinical signs of mastitis or other disease. The skin and teats were prepared with an antimicrobial protocol prior to each milk sampling. In total, 210 milk samples were collected and assessed for a number of bacterial colonies grown on each plate. Bacterial growth was detected in 180 samples (86%). , spp., spp., Coagulase-Negative Staphylococci (CoNS), spp., , spp., spp., and were identified from pure and/or mixed bacterial growth, listed in descending order of occurrence. Despite the small sample size, the consistent occurrence of bacteria in early postpartum dams indicates a genuine occurrence of bacteria in canine milk, rather than random contamination. The finding of bacteria in the milk of dams should not, therefore, be the sole argument for the diagnosis of mastitis.
PubMed: 37444004
DOI: 10.3390/ani13132206 -
Frontiers in Medicine 2021Bacterial keratitis is a serious and vision-threatening condition in veterinary and human patients, one that often requires culture and susceptibility testing to adjust...
Bacterial keratitis is a serious and vision-threatening condition in veterinary and human patients, one that often requires culture and susceptibility testing to adjust therapy and improve clinical outcomes. The present study challenges the antimicrobial susceptibility testing (AST) paradigm in ophthalmology, enabling more accurate -to- translation by incorporating factors normally present during host-pathogen interactions in clinical patients. Thirty bacteria (10 , 10 , 10 ) were isolated from canine patients with infectious keratitis. For each isolate, commercial plates (Sensititre™ JOEYE2) were used to assess the minimal inhibitory concentration (MIC) of 17 different antibiotics in the absence (0% albumin, control) or presence of canine albumin (0.01-2%). For , the experiment was repeated with actual tear fluid collected from canine eyes with ocular surface inflammation. Kruskal-Wallis, Wilcoxon signed rank test and Spearman's correlation tests were used for statistical analysis. Clinical outcomes were unfavorable in selected canine patients with bacterial keratitis (e.g., globe perforation, graft dehiscence) despite standard AST (i.e., 0% albumin in test medium) confirming that most corneal infections (93%) were susceptible to ≥1 topical antibiotics used at the initial visit. Albumin levels ≥0.05% increased MICs in a dose-dependent, bacteria-specific, and antibiotic-specific manner. No significant differences ( = 1.000) were noted in MICs of any antibiotic whether albumin or tear fluid was added to the Mueller-Hinton broth. Percent protein binding inherent to each antibiotic was associated with clinical interpretations (Spearman's rho = -0.53, = 0.034) but not changes in MICs. Albumin in tears impacted the efficacy of selected ophthalmic antibiotics as only the unbound portion of an antibiotic is microbiologically active. The present findings could improve decision making of clinicians managing bacterial keratitis, reduce development of antimicrobial resistance, influence current guidelines set by the Clinical and Laboratory Standards Institute, and serve as a reference for bacteriological evaluations across medical fields and across species.
PubMed: 34917625
DOI: 10.3389/fmed.2021.663212 -
Microbiology Resource Announcements Jun 2024We report seven draft genome sequences of strains revealing reduced penicillin-G susceptibility. The genomes measured 2.054-2.385 Mbp, with G+C contents of 38.8%-39.6%....
We report seven draft genome sequences of strains revealing reduced penicillin-G susceptibility. The genomes measured 2.054-2.385 Mbp, with G+C contents of 38.8%-39.6%. Amino acid substitutions in penicillin-binding proteins were characterized as compared with those of NCTC 12191(T) genome sequence (GenBank accession number NZ_LR134293.1).
PubMed: 38742884
DOI: 10.1128/mra.00219-24 -
Virulence Dec 2019Streptococcus canis is a zoonotic agent that causes serious invasive diseases in domestic animals and humans, but knowledge about its pathogenic potential and underlying...
Streptococcus canis is a zoonotic agent that causes serious invasive diseases in domestic animals and humans, but knowledge about its pathogenic potential and underlying virulence mechanisms is limited. Here, we report on the ability of certain S. canis isolates to form large bacterial aggregates when grown in liquid broth. Bacterial aggregation was attributed to the presence and the self-binding activity of SCM, the M protein of S. canis, as evaluated by bacterial sedimentation assays, immunofluorescence- and electron microscopic approaches. Using a variety of truncated recombinant SCM fragments, we demonstrated that homophilic SCM interactions occur via the N-terminal, but not the C-terminal part, of the mature M protein. Interestingly, when incubated in human plasma, SCM forms soluble protein complexes comprising its known ligands, immunoglobulin G (IgG) and plasminogen (Plg). Co-incubation studies with purified host proteins revealed that SCM-mediated complex formation is based on the interaction of SCM with itself and with IgG, but not with Plg or fibrinogen (Fbg), well-established constituents of M protein-mediated protein complexes in human-associated streptococci. Notably, these soluble, SCM-mediated plasma complexes harbored complement factor C1q, which can induce complement breakdown in the periphery and therefore represent another immune evasion mechanism of SCM.
Topics: Antibodies, Bacterial; Antigens, Bacterial; Bacterial Adhesion; Bacterial Outer Membrane Proteins; Carrier Proteins; Fibrinogen; Humans; Immunoglobulin G; Protein Binding; Streptococcus
PubMed: 30829556
DOI: 10.1080/21505594.2019.1589362 -
PloS One 2022Laboratory surveillance and the monitoring of antimicrobial resistance (AMR) trends and patterns among local isolates have been highly effective in providing...
Laboratory surveillance and the monitoring of antimicrobial resistance (AMR) trends and patterns among local isolates have been highly effective in providing comprehensive information for public health decision-making. A total of 396 cases along with 449 specimens were received for antibiotic susceptibility testing at a public university veterinary diagnostic laboratory in Malaysia between 2015 and 2017. Escherichia coli was the most frequently isolated (n = 101, 13%) bacteria, followed by Staphylococcus pseudintermedius (n = 97, 12%) and Streptococcus canis (n = 62, 8%). In cats, S. pseudintermedius isolates were highly resistant to azithromycin (90%), while the E. coli isolates were highly resistant to doxycycline (90%), tetracycline (81%), and cephalexin (75%). About 55% of S. pseudintermedius and 82% of E. coli were multi-drug resistant (MDR). In dogs, S. intermedius isolates were highly resistant to aminoglycosides neomycin (90.9%) and gentamicin (84.6%), and tetracycline (75%). Whereas the E. coli isolates were highly resistant to cephalexin (82.1%) and amoxicillin/clavulanic acid (76.5%). MDR was observed in 60% of S. intermedius and 72% of E. coli from dogs. Generally, the bacterial isolates from cats demonstrated higher levels of resistance to multiple antibiotics compared to those from dogs.
Topics: Cats; Dogs; Animals; Anti-Bacterial Agents; Escherichia coli; Retrospective Studies; Drug Resistance, Bacterial; Drug Resistance, Multiple
PubMed: 36477195
DOI: 10.1371/journal.pone.0277664 -
Veterinary Sciences Apr 2023An 8-year-old male Rhodesian Ridgeback was presented with fever and severe thrombocytopenia. Clinical and laboratory examination, echocardiography, blood culture, and...
An 8-year-old male Rhodesian Ridgeback was presented with fever and severe thrombocytopenia. Clinical and laboratory examination, echocardiography, blood culture, and pathohistology revealed evidence of infective endocarditis, ischemic renal infarcts, and septic encephalitis. Treatment was started immediately but the dog's condition worsened, and the dog had to be euthanized. The causative strain was detected by blood culture and MALDI-TOF MS and analyzed using whole-genome sequencing and multilocus sequence typing. Antibiotic susceptibility testing did not detect any resistance. The affected heart valve was analyzed using FISH imaging, which showed a streptococcal biofilm on the heart valve. Bacteria in biofilms are recalcitrant to antibiotic treatment. Early diagnosis could be beneficial to treatment outcome. Treatment of endocarditis could be improved by researching the optimal dosage of antibiotics in conjunction with the use of biofilm-active drugs.
PubMed: 37235397
DOI: 10.3390/vetsci10050314 -
Journal of Investigative Medicine High... 2019A middle-aged man presented with fever and shortness of breath. He had significant history of congestive heart disease and received deceased donor renal transplant 2...
A middle-aged man presented with fever and shortness of breath. He had significant history of congestive heart disease and received deceased donor renal transplant 2 years prior to presentation. He was febrile and found to have sepsis. His initial blood cultures grew Streptococcus canis. Streptococcus canis causes rare infection in humans, and this is most likely the first case in the renal transplant population.
Topics: Bacteremia; Humans; Immunocompromised Host; Kidney Transplantation; Male; Middle Aged; Streptococcal Infections; Streptococcus; Transplant Recipients
PubMed: 30929468
DOI: 10.1177/2324709619834592 -
Frontiers in Veterinary Science 2020The objective of this study was to describe bacterial culture and antibiotic susceptibility results in 476 dogs presenting with suspected bacterial keratitis in Iowa and...
The objective of this study was to describe bacterial culture and antibiotic susceptibility results in 476 dogs presenting with suspected bacterial keratitis in Iowa and surrounding Midwestern states, further detailing trends in patient characteristics, seasonality, and antimicrobial resistance. Corneal swabs yielded 465 bacterial isolates and 220 cultures (46.2%) with no apparent growth (0-5 isolates per culture). The most frequent bacterial genera were (32.3%), (19.1%), and (12.5%), while the most common bacterial species were (26.7%), (12%), and (7.5%). Compared to mixed-breed dogs, canine breeds most likely to be examined for ulcerative keratitis included Boston terrier, Cavalier King Charles spaniel, miniature pinscher, pug, rat terrier, Saint Bernard, shih tzu, and silky terriers. In summer, the likelihood to yield a negative culture was reduced while the likelihood to culture species was increased. Bacteria considered multidrug resistant (MDR, resistant to ≥ 3 antibiotic classes) represented 20% of all canine isolates and were most prevalent for species (33%). An alarming, escalating trend of MDR prevalence was noted between 2016 (5%) and 2020 (34%). Individual ophthalmic preparations (i.e., single antibiotics or commercially available antibiotic combinations) with highest efficacy against all bacterial isolates included chloramphenicol (83%), ceftiofur (79%), amikacin (77%), neomycin-polymyxin B-bacitracin (77%), and gentamicin (74%). Efficacy of systemic antibiotics and combinations of ophthalmic preparations was also evaluated. Based on the present findings, triple antibiotic (Neo-Poly-Bac) is recommended as empirical monotherapy for prophylactic antibiotic therapy in dogs with simple corneal ulcers, while a chloramphenicol-ciprofloxacin combination is empirically recommended for therapeutic management of infected corneal ulcers. Pending culture and susceptibility results, appropriate selection of empiric antibiotic therapy is important to enhance therapeutic outcome and reduce antibacterial resistance in dogs with corneal ulceration.
PubMed: 33330707
DOI: 10.3389/fvets.2020.583965