RESUMO
Populations of the eastern hellbender Cryptobranchus alleganiensis alleganiensis have been declining for decades, and emerging pathogens and pesticides are hypothesized to be contributing factors. However, few empirical studies have attempted to test the potential effects of these factors on hellbenders. We simultaneously exposed subadult hellbenders to environmentally relevant concentrations of either Batrachochytrium dendrobatidis (Bd) or a frog virus 3-like ranavirus (RV), a combination of the pathogens, or each pathogen following exposure to a glyphosate herbicide (Roundup). Additionally, we measured the ability of the skin mucosome to inactivate Bd and RV in growth assays. We found that mucosome significantly inactivated RV by an average of 40% but had no negative effects on Bd growth. All treatments that included RV exposure experienced reduced survival compared to controls, and the combination of RV and herbicide resulted in 100% mortality. Histopathology verified RV as the cause of mortality in all RV-exposed treatments. No animals were infected with Bd or died in the Bd-only treatment. Our results suggest that RV exposure may be a significant threat to the survival of subadult hellbenders and that Roundup exposure may potentially exacerbate this threat.
Assuntos
Infecções por Vírus de DNA/veterinária , Glicina/análogos & derivados , Herbicidas/administração & dosagem , Imunidade Inata , Micoses/veterinária , Urodelos/imunologia , Animais , Batrachochytrium/fisiologia , Infecções por Vírus de DNA/virologia , Glicina/administração & dosagem , Micoses/microbiologia , Ranavirus/fisiologia , GlifosatoRESUMO
Six Staphylococcus strains were isolated from healthy black bears (Ursus americanus) in the Great Smoky Mountains National Park, Tennessee, USA. Phylogenetic analysis based on complete genome, 16S rRNA, dnaJ, hsp60, rpoB and sodA genes, and MALDI-TOF-MS main spectral profiles revealed that the strains belonged to one species and showed the closest relatedness to members of the 'Staphylococcus intermedius group' (SIG), which include Staphylococcus intermedius, Staphylococcus pseudintermedius, Staphylococcus delphini and Staphyloccoccus cornubiensis. The strains were positive in SIG-specific and negative in individual species-specific PCR assays for the nuc gene. The strains can be differentiated from the other SIG species by the absence of sucrose fermentation, from S. intermedius DSM 20373T, S. pseudintermedius CCUG 49543T and S. cornubiensis DSM 105366T by the absence of methyl ß-d-glucopyranoside fermentation and from S. delphini DSM 20771T by fermentation of trehalose. DNA relatedness of the type strain MI 10-1553T with the type strains of S. delphini, S. pseudintermedius, S. intermedius and S. cornubiensis was ≤48.2â% by digital DNA-DNA hybridization and ≤92.3â% by average nucleotide identity calculations. Iso-C15:0, anteiso-C15â:â0 and anteiso-C17â:â0 were the most common fatty acids. Polar lipids consisted of phosphadidylglycerols, phospholipids, glycolipid, diphosphatidylglycerol and aminophospholipid. Cell-wall peptidoglycan was of type A3α l-Lys-Gly3 (Ser; similar to A11.2 and A11.3). The respiratory quinone belonged to menaquinone 7 (MK-7). The G+C content of MI 10-1553T was 39.3 mol%. The isolated strains represent a novel species of the genus Staphylococcus, for which we propose the name Staphylococcus ursi sp. nov. The type strain is MI 10-1553T (=ATCC TSD-55T=CCOS 1900T).
Assuntos
Filogenia , Staphylococcus/classificação , Ursidae/microbiologia , Animais , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Ácidos Graxos/química , Genes Bacterianos , Hibridização de Ácido Nucleico , Peptidoglicano/química , Fosfolipídeos/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Staphylococcus/isolamento & purificação , Staphylococcus intermedius/genética , Tennessee , Vitamina K 2/análogos & derivados , Vitamina K 2/químicaRESUMO
The Staphylococcus intermedius group (SIG) is a collection of coagulase-positive staphylococci consisting of four distinct species, namely, Staphylococcus cornubiensis, Staphylococcus delphini, Staphylococcus intermedius, and Staphylococcus pseudintermedius SIG members are animal pathogens and rare causes of human infection. Accurate identification of S. pseudintermedius has important implications for interpretation of antimicrobial susceptibility testing data and may be important for other members of the group. Therefore, we sought to evaluate the performance of five commercially available identification platforms with 21 S. delphini isolates obtained from a variety of animal and geographic sources. Here, we show that automated biochemical platforms were unable to identify S. delphini to the species level, a function of its omission from their databases, but could identify isolates to the SIG level with various degrees of success. However, all automated systems misidentified at least one isolate as Staphylococcus aureus One matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) system was able to identify S. delphini to the species level, suggesting that MALDI-TOF MS is the best option for distinguishing members of the SIG. With the exception of S. pseudintermedius, it is unclear if other SIG members should be routinely identified to the species level; however, as our understanding of their role in animal and human diseases increases, it may be necessary and important to do so.
Assuntos
Automação Laboratorial/instrumentação , Automação Laboratorial/normas , Infecções Estafilocócicas/veterinária , Staphylococcus/química , Staphylococcus/isolamento & purificação , Animais , Automação Laboratorial/métodos , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Infecções Estafilocócicas/diagnóstico , Infecções Estafilocócicas/microbiologia , Staphylococcus aureus/isolamento & purificação , Staphylococcus hyicus/isolamento & purificação , Staphylococcus intermedius/isolamento & purificaçãoRESUMO
BACKGROUND: Approved treatments for canine otitis externa are limited in variety and may contain ototoxic ingredients. With bacterial resistance an ongoing concern, it would be ideal if non-ototoxic agents combined with antibiotics resulted in a synergistic effect, requiring lower antibiotic concentrations to treat infections. Evidence of synergism and antagonism between N-acetylcysteine (NAC) and various antibiotic classes has been reported; the present research group was interested in examining these interactions. HYPOTHESIS/OBJECTIVES: To determine if NAC, an otoprotective and antimicrobial compound, has synergistic activity when combined with enrofloxacin or gentamicin in vitro against bacterial isolates causing canine otitis externa. ANIMALS: Twenty-two isolates from canine clinical cases of otitis externa were identified and tested, including seven Staphylococcus pseudintermedius, 12 Pseudomonas aeruginosa and three Corynebacterium spp. isolates. METHODS AND MATERIALS: Each isolate was grown on blood agar for 24 h and transferred to Mueller-Hinton broth (MHB), with a final concentration of 5 × 105 cfu/mL. Each well was inoculated with 50 µL of bacterial suspension. N-acetylcysteine was diluted in MHB to a starting concentration of 160 mg/mL. Enrofloxacin and gentamicin were diluted to 64 µg/mL. Individual and checkerboard serial microdilution assays were performed in triplicate with negative controls for all isolates tested. RESULTS: Interactions observed for NAC and enrofloxacin were synergistic (4.5%), indifferent (77.3%) or antagonistic (18.2%). Interactions observed for NAC and gentamicin were synergistic (4.5%), indifferent (45.5%) or antagonistic (50%). CONCLUSIONS AND CLINICAL RELEVANCE: Most interactions between NAC and enrofloxacin or gentamicin were indifferent or antagonistic at the concentrations tested in vitro.
Assuntos
Acetilcisteína/farmacologia , Antibacterianos/farmacologia , Bactérias/efeitos dos fármacos , Doenças do Cão/microbiologia , Otite Externa/veterinária , Animais , Cães , Sinergismo Farmacológico , Testes de Sensibilidade Microbiana , Otite Externa/microbiologiaRESUMO
Coagulase activation of prothrombin by staphylococcus induces the formation of fibrin deposition that facilitates the establishment of infection by Staphylococcus species. Coagulase activity is a key characteristic of Staphylococcus pseudintermedius; however, no coagulase gene or associated protein has been studied to characterize this activity. We report a recombinant protein sharing 40% similarity to Staphylococcus aureus coagulase produced from a putative S. pseudintermedius coagulase gene. Prothrombin activation by the protein was measured with a chromogenic assay using thrombin tripeptide substrate. Stronger interaction with bovine prothrombin than with human prothrombin was observed. The S. pseudintermedius coagulase protein also bound complement C3 and immunoglobulin. Recombinant coagulase facilitated the escape of S. pseudintermedius from phagocytosis, presumably by forming a bridge between opsonizing antibody, complement, and fibrinogen. Evidence from this work suggests that S. pseudintermedius coagulase has multifunctional properties that contribute to immune evasion that likely plays an important role in virulence.
Assuntos
Coagulase/genética , Coagulase/metabolismo , Evasão da Resposta Imune , Protrombina/metabolismo , Staphylococcus/enzimologia , Staphylococcus/genética , Animais , Compostos Cromogênicos/metabolismo , Clonagem Molecular , Colorimetria , Complemento C3/metabolismo , Cães , Imunoglobulinas/metabolismo , Cinética , Fagocitose , Ligação Proteica , Coelhos , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Homologia de Sequência , Trombina/análise , Fatores de Virulência/genética , Fatores de Virulência/metabolismoRESUMO
Whole-genome sequencing of Staphylococcus xylosus strain JW2311 from bovine mastitis milk identified the novel 49.3-kb macrolide-lincosamide-streptogramin B (MLSB) resistance plasmid pJW2311. It contained the macrolide resistance gene mph(C), the macrolide-streptogramin B resistance gene msr(A), and the new MLSB resistance gene erm(48) and could be transformed into Staphylococcus aureus by electroporation. Functionality of erm(48) was demonstrated by cloning and expression in S. aureus.
Assuntos
Antibacterianos/farmacologia , Lincosamidas/farmacologia , Macrolídeos/farmacologia , Plasmídeos/genética , Staphylococcus/efeitos dos fármacos , Estreptogramina B/farmacologia , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Farmacorresistência Bacteriana Múltipla/genética , Testes de Sensibilidade MicrobianaRESUMO
Clinical reference textbooks lack data for pyrrolidonyl arylamidase (PYR) activity in Staphylococcus delphini This study evaluated PYR activities of 21 S. delphini strains by reference broth, rapid disc, and rapid slide methods. Species and subgroup identifications were confirmed by nucleic acid-based methods and included nine group A and 12 group B strains. Testing by rapid PYR methods with products from four manufacturers was performed at two testing locations, and, with the exception of one strain tested at one location using reagents from one manufacturer, each S. delphini strain tested positive for PYR activity. Therefore, PYR may be a useful single-test adjunct for distinguishing Staphylococcus aureus from S. delphini and other members of the Staphylococcus intermedius group.
Assuntos
Aminopeptidases/análise , Staphylococcus/enzimologia , Animais , Técnicas Bacteriológicas/métodos , Humanos , Staphylococcus/classificação , Staphylococcus/isolamento & purificaçãoRESUMO
BACKGROUND: N-Acetylcysteine (NAC) has the potential to be a useful therapeutic agent for the treatment of otitis externa due to its antimicrobial and mucolytic properties, as well as its ability to disrupt bacterial biofilm. HYPOTHESIS/OBJECTIVES: To determine the antibacterial activity of NAC against common bacterial isolates associated with canine otitis externa. ANIMALS: Twenty two isolates from canine clinical cases of otitis externa were identified and tested, including five Staphylococcus pseudintermedius, six Pseudomonas aeruginosa, five Corynebacterium spp. and six ß-haemolytic Streptococcus spp. isolates. METHODS: Each isolate was grown on blood agar for 24 h and transferred to Mueller Hinton Broth (MHB) to achieve a final concentration of 5 × 10(5) CFU/mL. NAC was diluted in MHB to a starting concentration of 160 mg/mL and serial two-fold microdilution assays were performed in triplicate with negative controls for all isolates tested. Concentrations of NAC tested ranged from 0.125 to 80 mg/mL. A 50 µL volume of bacterial suspension was used to inoculate each well. RESULTS: The minimum inhibitory concentration (MIC) of NAC for all isolates tested ranged from 5 to 20 mg/mL. CONCLUSIONS AND CLINICAL RELEVANCE: N-Acetylcysteine inhibits clinically relevant and drug resistant bacteria in vitro, and has potential for use as a novel agent for treatment of otitis externa.
Assuntos
Acetilcisteína/uso terapêutico , Antibacterianos/uso terapêutico , Bactérias/efeitos dos fármacos , Doenças do Cão/microbiologia , Otite Externa/veterinária , Animais , Cães , Testes de Sensibilidade Microbiana , Otite Externa/microbiologiaRESUMO
Use of disinfectants by biologists, veterinarians, and zoological facilities is a standard biosecurity procedure to prevent contamination and the spread of pathogens. We tested the efficacy of 5 disinfectants and 1 anti-fungal treatment, at 1 and 5 min contact durations, in inactivating Batrachochytrium dendrobatidis (Bd) grown on tryptone media. Our study focused on concentrations of disinfectants known to inactivate ranaviruses, which can be found at the same sites as Bd and can concurrently infect amphibians. Disinfectants tested were chlorhexidine gluconate (0.25, 0.75, and 2%), Pro-San (0.19, 0.35, and 0.47%), Virkon S (1%), household bleach (0.2, 1, and 3%), and Xtreme Mic (5%). The anti-fungal was terbinafine HCl at 0.005, 0.05, 0.1, and 1 mg ml-1. Inactivation of Bd was determined by microscopic evaluation of zoospore motility and growth of colony mass after 14 d. All disinfectants were effective at inactivating zoospore motility and colony growth of Bd at all concentrations and both contact times; however, terbinafine HCl inactivated Bd at only the highest concentration tested (1 mg ml-1) and 5 min duration. Thus, a minimum of 0.25% chlorhexidine gluconate, 0.19% Pro-San, 1% Virkon, 0.2% bleach, and 5% Xtreme Mic with 1 min contact was sufficient to inactivate Bd. Also, terbinafine HCl (1 mg ml-1) with a 5 min contact time might be effective in treating amphibians infected with Bd. Based on this study and previously published findings, 0.75% Nolvasan, 1% Virkon S, and 3% bleach with 1 min contact are sufficient to inactivate both Bd and ranaviruses.
Assuntos
Antifúngicos/farmacologia , Quitridiomicetos/efeitos dos fármacos , Desinfetantes/farmacologia , Naftalenos/farmacologia , Testes de Sensibilidade Microbiana , TerbinafinaRESUMO
BACKGROUND: The prevalence of meticillin- and multidrug-resistant Staphylococcus pseudintermedius (MRSP) in canine pyoderma has been increasing in recent years; thus, treatment of these cases has become challenging. HYPOTHESIS/OBJECTIVES: To compare treatment outcome (clinical resolution and treatment duration), adverse effects of medication, and concurrent diseases and medications in dogs with meticillin-susceptible S. pseudintermedius (MSSP) and MRSP pyoderma. ANIMALS/METHODS: Medical records were reviewed retrospectively, and 123 MSSP and 93 MRSP clinical cases between January 2008 and April 2010 were included. RESULTS: In MSSP infections, cefalexin and cefpodoxime were the most commonly prescribed antimicrobials, accounting for 43.2 and 34.4% of cases, respectively. In MRSP infections, chloramphenicol and doxycycline were most commonly prescribed, accounting for 52.6 and 14.4% of cases, respectively. Adverse effects were reported in seven MSSP and 31 MRSP cases. The most commonly reported adverse effects were gastrointestinal, prompting antibiotic discontinuation in three MSSP and 20 MRSP cases. Chloramphenicol was associated with the highest incidence of adverse reactions (27 of 51 cases). Of 164 cases with follow up, 43 of 88 MSSP infections and 29 of 76 MRSP infections achieved complete clinical resolution at the first recheck examination. Three MSSP and seven MRSP cases failed to improve or resolve at subsequent visits assessed at 3-4 week intervals. CONCLUSIONS AND CLINICAL IMPORTANCE: Results from this study showed that the majority of pyodermas resolved regardless of meticillin susceptibility. Although some cases of MRSP pyoderma took longer to treat, this is likely to be because of chronicity and not the organism. In addition, adverse effects were frequently associated with chloramphenicol administration.
Assuntos
Antibacterianos/uso terapêutico , Resistência a Meticilina , Pioderma/veterinária , Infecções Cutâneas Estafilocócicas/veterinária , Staphylococcus/classificação , Staphylococcus/efeitos dos fármacos , Animais , Antibacterianos/efeitos adversos , Cães , Pioderma/tratamento farmacológico , Pioderma/microbiologia , Estudos Retrospectivos , Infecções Cutâneas Estafilocócicas/tratamento farmacológico , Infecções Cutâneas Estafilocócicas/microbiologiaRESUMO
A blue-fronted Amazon parrot (Amazona aestiva) was presented with a granuloma involving the proximal rhinotheca and extending into the rostral sinuses. Mycobacterium marinum was diagnosed based on results of biopsy and culture. Treatment was initiated with clarithromycin, rifampin, and ethambutol, but the bird died 4 months after the onset of antimicrobial therapy. Additional granulomas were found in the left lung and liver on postmortem examination. Mycobacterial isolation on postmortem samples was unsuccessful. This is the first report of Mycobacterium marinum in a bird.
Assuntos
Amazona , Doenças das Aves/microbiologia , Infecções por Mycobacterium não Tuberculosas/veterinária , Mycobacterium marinum , Animais , Antibacterianos/uso terapêutico , Bico/microbiologia , Bico/patologia , Evolução Fatal , Hepatopatias/tratamento farmacológico , Hepatopatias/microbiologia , Hepatopatias/patologia , Hepatopatias/veterinária , Pneumopatias/tratamento farmacológico , Pneumopatias/microbiologia , Pneumopatias/patologia , Pneumopatias/veterinária , Infecções por Mycobacterium não Tuberculosas/tratamento farmacológico , Infecções por Mycobacterium não Tuberculosas/patologiaRESUMO
OBJECTIVES: The aim of this study was to determine the phenotypic and genotypic resistance profiles of methicillin-resistant Staphylococcus pseudintermedius (MRSP) and to examine the clonal distribution in Europe and North America. METHODS: A total of 103 MRSP isolates from dogs isolated from several countries in Europe, the USA and Canada were characterized. Isolates were identified by PCR-restriction fragment length polymorphism (RFLP), antimicrobial susceptibility was determined by broth dilution or gradient diffusion, and antimicrobial resistance genes were detected using a microarray. Genetic diversity was assessed by multilocus sequence typing (MLST), PFGE and spa typing. Staphylococcal cassette chromosome mec (SCCmec) elements were characterized by multiplex PCR. RESULTS: Thirteen different sequence types (STs), 18 PFGE types and 8 spa types were detected. The hybrid SCCmec element II-III described in a MRSP isolate was present in 75 (72.8%) isolates. The remaining isolates either had SCCmec type III (n=2), IV (n=6), V (n=14) or VII-241 (n=4) or were non-typeable (n=2). The most common genotypes were ST71(MLST)-J(PFGE)-t02(spa)-II-III(SCCmec) (56.3%) and ST68-C-t06-V (12.6%). In addition to mecA-mediated beta-lactam resistance, isolates showed resistance to trimethoprim [dfr(G)] (90.3%), gentamicin/kanamycin [aac(6')-Ie-aph(2')-Ia] (88.3%), kanamycin [aph(3')-III] (90.3%), streptomycin [ant(6')-Ia] (90.3%), streptothricin (sat4) (90.3%), macrolides and/or lincosamides [erm(B), lnu(A)] (89.3%), fluoroquinolones (87.4%), tetracycline [tet(M) and/or tet(K)] (69.9%), chloramphenicol (cat(pC221)) (57.3%) and rifampicin (1.9%). CONCLUSIONS: Two major clonal MRSP lineages have disseminated in Europe (ST71-J-t02-II-III) and North America (ST68-C-t06-V). Regardless of their geographical or clonal origin, the isolates displayed resistance to the major classes of antibiotics used in veterinary medicine and thus infections caused by MRSP isolates represent a serious therapeutic challenge.
Assuntos
Doenças do Cão/epidemiologia , Doenças do Cão/microbiologia , Staphylococcus aureus Resistente à Meticilina/classificação , Staphylococcus aureus Resistente à Meticilina/isolamento & purificação , Polimorfismo Genético , Infecções Estafilocócicas/veterinária , Animais , Técnicas de Tipagem Bacteriana , Impressões Digitais de DNA , Cães , Europa (Continente)/epidemiologia , Genes Bacterianos , Análise em Microsséries , Testes de Sensibilidade Microbiana , América do Norte/epidemiologia , Polimorfismo de Fragmento de Restrição , Infecções Estafilocócicas/epidemiologia , Infecções Estafilocócicas/microbiologiaRESUMO
Lycoperdonosis is a rare respiratory disease that results from the inhalation of spores released from the Lycoperdon (puffball) mushroom. In the present study, 2 cases of confirmed canine lycoperdonosis are described. The first case presented to the Matthew J. Ryan Veterinary Hospital of the University of Pennsylvania, and the second case was submitted for postmortem examination to the University of Tennessee Veterinary Teaching Hospital. Both dogs presented in respiratory distress, and owners reported that the dogs had been playing or digging in areas with puffball mushrooms prior to the onset of clinical signs. In the initial case, thoracic radiographs revealed a diffuse interstitial and multifocal alveolar pulmonary pattern. Despite aggressive medical treatment and mechanical ventilation, the dog continued to worsen and was euthanized. Postmortem examination revealed firm lung lobes and enlarged tracheobronchial lymph nodes. Histologically, there was a severe diffuse histiocytic and pyogranulomatous bronchointerstitial pneumonia. Throughout the lung and lymph nodes, most commonly within macrophages, were round, 3-5 µm in diameter, Gomori methenamine silver-positive structures, consistent with Lycoperdon spores. An approximately 750-base pair DNA fragment was amplified from lung of both cases by polymerase chain reaction using primers specific to yeast ribosomal DNA, and the sequence of the fragment was determined to be most closely related to Lycoperdon pyriforme. Importantly, reexamination of an endotracheal wash from the initial case revealed intrahistiocytic spores, suggesting that airway sampling may assist in diagnosing lycoperdonosis.
Assuntos
Doenças do Cão/diagnóstico , Pneumopatias Fúngicas/veterinária , Micoses/veterinária , Animais , Doenças do Cão/patologia , Cães , Feminino , Insônia Familiar Fatal , Pneumopatias Fúngicas/diagnóstico , Pneumopatias Fúngicas/patologia , Masculino , Micoses/diagnóstico , Micoses/patologia , Esporos FúngicosRESUMO
OBJECTIVE: To evaluate knowledge, attitudes, and management practices involving antimicrobial use among Tennessee beef producers. DESIGN: Mail survey. SAMPLE POPULATION: A population-based, stratified random sample of 3,000 beef producers across the state. PROCEDURES: Questionnaires were mailed to beef producers. Questions focused on producer practices related to education, biosecurity, veterinary use, and the purchase and use of antimicrobials. Operation types were categorized as either cow-calf only or multiple operation type (MOT). Associations between various factors and antimicrobial use were evaluated by use of multivariable logistic regression, with the outcome variable being any antimicrobial use (injectable or by mouth) in the past year. RESULTS: Of 3,000 questionnaires mailed, 1,042 (34.7%) were returned. A significantly higher proportion of producers with MOTs reported giving antimicrobials by mouth or by injection than did producers with cow-calf only operations. In addition, higher proportions of producers with MOTs than producers with cow-calf only operations reported treating with macrolides, florfenicol, ceftiofur, and aminoglycosides. In the multivariable analysis, herd size>50 cattle, participation in Beef Quality Assurance or master beef producer certification programs, quarantining of newly purchased animals, use of written instructions for treating disease, and observation of withdrawal times were associated with a higher likelihood of antimicrobial use. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggested that producers who engaged in more progressive farming practices were also more likely to use antimicrobials. Incorporating training on judicious antimicrobial use into educational programs would likely increase awareness of best management practices regarding antimicrobial use.
Assuntos
Antibacterianos/administração & dosagem , Bovinos , Ração Animal , Criação de Animais Domésticos , Animais , Coleta de Dados , Feminino , Conhecimentos, Atitudes e Prática em Saúde , Masculino , Inquéritos e Questionários , TennesseeRESUMO
Staphylococcus pseudintermedius is a major opportunistic bacterial pathogen and the leading cause of pyoderma in dogs. In canines it is also often associated with infections of the urinary system and wounds and occasionally infects people. Widespread antimicrobial resistance has made the development of alternative treatments a high priority. The development of a staphylococcal vaccine, however, has proven challenging. Identification of virulence factors that inhibit phagocytosis and avoid innate immunity may play a significant role in preventing or treating infection with S. pseudintermedius. In this study, we identified a putative 5'-nucleotidase provisionally named SpAdsA, a S. pseudintermedius cell- wall protein encoded by SpAdsA. SpAdsA shares approximately 52% identity with the orthologous protein of Staphylococcus aureus and 14.8% identity with that of Streptococcus suis type2. It catalyzes the dephosphorylation of adenosine triphosphate and attenuation of this enzyme with critical amino acid substitutions nearly eliminated its hydrolytic activity. Exogenous adenosine inhibited phagocytosis of S. pseudintermedius by canine neutrophils and monocytes. Conversely, the addition of SpAdsA inhibitor or A2A adenosine receptor antagonist impaired the capacity of S. pseudintermedius to escape from killing by phagocytic cells. The neutralizing ability of canine antibody produced against SpAdsA-M was determined. Taken together, these results suggest that SpAdsA likely plays an important role in S. pseudintermedius virulence and that attenuated SpAdsA may be a good candidate for inclusion in a vaccine against S. pseudintermedius.
Assuntos
5'-Nucleotidase/imunologia , Fagócitos/microbiologia , Fagocitose , Staphylococcus/enzimologia , 5'-Nucleotidase/genética , Adenosina/farmacologia , Trifosfato de Adenosina/metabolismo , Animais , Proteínas de Bactérias/genética , Proteínas de Bactérias/imunologia , Parede Celular/química , Cães , Fagócitos/imunologia , Fosforilação , Staphylococcus/genética , Fatores de VirulênciaRESUMO
Clinical and Laboratory Standards Institute interpretive breakpoints for in vitro susceptibility tests that predict mecA-mediated oxacillin resistance in Staphylococcus pseudintermedius isolates from animals have been changed twice in the past decade. Moreover, there are no counterpart recommendations for human isolates of S. pseudintermedius. Individual medical and veterinary laboratories variably use interpretive breakpoints identical to those recommended for use with Staphylococcus aureus or identical to those recommended for use with coagulase-negative staphylococci. The purpose of the current study was to examine correlations between oxacillin disk diffusion, oxacillin gradient diffusion, oxacillin microbroth dilution, and cefoxitin disk diffusion tests used to predict mecA-mediated resistance in S. pseudintermedius and to retrospectively estimate, from disk diffusion zone diameter measurements, the prevalence and rate of increase of oxacillin resistance among canine S. pseudintermedius isolates submitted to a veterinary teaching hospital laboratory. Oxacillin disk diffusion zone diameters of Assuntos
Antibacterianos/farmacologia
, Proteínas de Bactérias/genética
, Doenças do Cão/microbiologia
, Farmacorresistência Bacteriana
, Infecções Estafilocócicas/veterinária
, Staphylococcus/efeitos dos fármacos
, Animais
, Proteínas de Bactérias/metabolismo
, Cefoxitina/farmacologia
, Cães
, Oxacilina/farmacologia
, Infecções Estafilocócicas/microbiologia
, Staphylococcus/isolamento & purificação
, Fatores de Tempo
RESUMO
On the basis of the scarcity of reports in the veterinary literature, it appears that Propionibacterium spp. are rarely associated with disease or isolated from cattle tissues. Recently, Propionibacterium spp. has been associated with multifocal abscessation in cattle. This report describes a case of necrosuppurative placentitis and abortion in an adult Holstein cow. Numerous colonies of small, pleomorphic, Gram-positive, rod-shaped bacteria were observed within the fibrin lattice associated with placental lesions and within the fetal atelectatic lung. Propionibacterium acnes was isolated in high numbers from the placenta, fetal lung, and stomach contents. To the authors' knowledge, this is the first report of placentitis associated with propionibacteria in a cow.
Assuntos
Aborto Animal/microbiologia , Doenças dos Bovinos/microbiologia , Infecções por Bactérias Gram-Positivas/veterinária , Doenças Placentárias/veterinária , Propionibacterium acnes/isolamento & purificação , Feto Abortado , Aborto Animal/patologia , Animais , Bovinos , Doenças dos Bovinos/patologia , Feminino , Infecções por Bactérias Gram-Positivas/microbiologia , Infecções por Bactérias Gram-Positivas/patologia , Histocitoquímica/veterinária , Doenças Placentárias/microbiologia , Doenças Placentárias/patologia , GravidezRESUMO
OBJECTIVE: To determine the prevalence of 4 urovirulence genes in fecal Escherichia coli isolates from healthy dogs and their owners and to determine whether detection of E coli strains with these genes was associated with a history of urinary tract infection (UTI). SAMPLE POPULATION: 61 healthy dog-owner pairs and 30 healthy non-dog owners. PROCEDURES: A fecal specimen was obtained from each participant, and 3 colonies of E coli were isolated from each specimen. A multiplex PCR assay was used to detect 4 genes encoding virulence factors: cytotoxic necrotizing factor (cnf), hemolysin (hlyD), s-fimbrial and F1C fimbriae adhesin (sfa/foc), and pilus associated with pyelonephritis G allele III (papGIII). Human participants completed a questionnaire to provide general information and any history of UTI for themselves and, when applicable, their dog. RESULTS: 26% (16/61) of dogs, 18% (11/61) of owners, and 20% (6/30) of non-dog owners had positive test results for >or= 1 E coli virulence gene. One or more genes were identified in fecal E coli isolates of both dog and owner in 2% (1/61) of households. There was no difference in the detection of any virulence factor between dog-owner pairs. Female owner history of UTI was associated with detection of each virulence factor in E coli strains isolated from their dogs' feces. CONCLUSIONS AND CLINICAL RELEVANCE: Dogs and humans harbored fecal E coli strains possessing the genes cnf, hlyD, sfa/foc, and papGIII that encode urovirulence factors. It was rare for both dog and owner to have fecal E coli strains with these virulence genes.
Assuntos
Toxinas Bacterianas/genética , Proteínas de Escherichia coli/genética , Escherichia coli/genética , Escherichia coli/patogenicidade , Fezes/microbiologia , Proteínas Hemolisinas/genética , Proteínas de Membrana Transportadoras/genética , Animais , Cães , Feminino , Humanos , VirulênciaRESUMO
OBJECTIVE: To determine prevalence of within-household sharing of fecal Escherichia coli between dogs and their owners on the basis of pulsed-field gel electrophoresis (PFGE), compare antimicrobial susceptibility between isolates from dogs and their owners, and evaluate epidemiologic features of cross-species sharing by use of a questionnaire. SAMPLE POPULATION: 61 healthy dog-owner pairs and 30 healthy control humans. PROCEDURES: 3 fecal E coli colonies were isolated from each participant; PFGE profiles were used to establish relatedness among bacterial isolates. Susceptibility to 17 antimicrobials was determined via disk diffusion. A questionnaire was used to evaluate signalment, previous antimicrobial therapy, hygiene, and relationship with dog. RESULTS: A wide array of PFGE profiles was observed in E coli isolates from all participants. Within-household sharing occurred with 9.8% prevalence, and across-household sharing occurred with 0.3% prevalence. No behaviors were associated with increased clonal sharing between dog and owner. No differences were found in susceptibility results between dog-owner pairs. Control isolates were more likely than canine isolates to be resistant to ampicillin and trimethoprim-sulfamethoxazole. Owners and control humans carried more multdrug-resistant E coli than did dogs. CONCLUSIONS AND CLINICAL RELEVANCE: Within-household sharing of E coli was detected more commonly than across-household sharing, but both direct contact and environmental reservoirs may be routes of cross-species sharing of bacteria and genes for resistance. Cross-species bacterial sharing is a potential public health concern, and good hygiene is recommended.
Assuntos
Antibacterianos/farmacologia , Cães/microbiologia , Escherichia coli/efeitos dos fármacos , Fezes/microbiologia , Animais , Eletroforese em Gel de Campo Pulsado , Escherichia coli/isolamento & purificação , Desinfecção das Mãos , Vínculo Humano-Animal , Humanos , Testes de Sensibilidade Microbiana , Valores de Referência , Inquéritos e QuestionáriosRESUMO
To determine the zoonotic risk from meticillin-resistant staphylococcal species or transfer of resistance genes between dogs with pyoderma and their owners, 25 dog-owner pairs were studied. Cultures were obtained from the dog's lesions and the owner's nasal cavity on the initial visit. Staphylococcus isolates were identified and antimicrobial susceptibility tests were performed by the Kirby-Bauer disk diffusion method. Presence of the mecA gene was determined by PCR. Staphylococcal Cassette Chromosome (SCCmec) typing was performed by multiplex PCR. Eighteen dogs had a meticillin-resistant staphylococcal species, with meticillin-resistant S. pseudintermedius (MRSP) isolated from 15 dogs. MRSP was isolated from two owners of dogs with MRSP skin infections. Both organisms had the same susceptibility pattern and SCCmec type. MRSP was not isolated from the owners after treating both dogs for 1 month. At least one coagulase-negative Staphylococcus spp. (CoNS) was isolated from each owner, with meticillin resistance found in 16 (64%) of the isolates. The mecA gene was identified in all but two of the meticillin-resistant Staphylococcus spp. Multiplex PCR identified SCCmec type V in all MRSP. The mecA gene-possessing CoNS isolates from owners contained either SCCmec type IVa or IVc. In conclusion, MRSP colonization of owners appeared to be uncommon and transient. Human nasal carriage of meticillin-resistant CoNS was common, but the SCCmec types were different from those in the canine MRSP isolates. Owners do not appear to be at great risk of zoonotic transfer of organisms or antimicrobial resistance genes from dogs with MRSP infections, but the findings should be confirmed with a much larger cohort.