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1.
Vet Res ; 52(1): 132, 2021 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-34663465

RESUMO

The study aim was to determine the expression of genes potentially related to chronic mastitis at the mRNA and protein levels, viz. chemokine C-C motif receptor 1 (CCR1), C-C motif chemokine ligand 2 (CCL2), C-C motif chemokine ligand 5 (CXCL5), tumor necrosis factor α (TNFα), interleukin 1ß (IL-1ß), interleukin 6 (IL-6), interleukin 8 (IL-8), interleukin 18 (IL-18), in bovine mammary gland parenchyma. The study examines the differences in expression of selected genes between cows with chronic mastitis caused by coagulase-positive (CoPS) or coagulase-negative staphylococci (CoNS) and those with healthy udders (H). Samples were collected from the udder quarters from 40 Polish Holstein-Friesian cows; 54 of these samples were chosen for analysis based on microbiological analysis of milk taken two days before slaughter. They were categorized into three groups: CoPS (N = 27), CoNS (N = 14) and H (N = 13). The RNA expression was analyzed by RT-qPCR and protein concentration by ELISA. No differences in the mRNA levels of seven genes (TNFα, IL-18, CCR1, IL-1ß, CCL2, IL-8, IL-6) and four proteins (TNFα, IL-18, CCR1, IL-1ß) were identified between the CoPS and H groups. Higher transcript levels of CXCL5 (p ≤ 0.05) gene were noted in CoPS than in H. Compared to H, higher concentrations of IL-8 and CXCL5 (p ≤ 0.05) were observed in CoPS (0.05 < p < 0.1) and CCL2 (0.05 < p < 0.1) in CoNS, while lower levels of Il-6 were found in CoPS. This may suggest that during chronic mastitis the organism stops producing pro-inflammatory cytokines, probably to protect the host tissues against their damage during prolonged infection.


Assuntos
Doenças dos Bovinos/metabolismo , Citocinas/genética , Expressão Gênica , Glândulas Mamárias Animais/metabolismo , Tecido Parenquimatoso/metabolismo , Infecções Estafilocócicas/veterinária , Animais , Bovinos , Doenças dos Bovinos/microbiologia , Doença Crônica/veterinária , Citocinas/metabolismo , Feminino , Infecções Estafilocócicas/metabolismo , Infecções Estafilocócicas/microbiologia , Staphylococcus/fisiologia
2.
Vet Res ; 52(1): 137, 2021 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-34711282

RESUMO

Although extensive research has been performed on bovine non-aureus staphylococci (NAS), several aspects such as bacteria-host interaction remain largely unstudied. Moreover, only a few mastitis pathogen challenge studies in cows have been conducted in the dry period, an important period that allows intramammary infection (IMI) to cure and new IMI to occur. We challenged 16 quarters of 4 Holstein Friesian cows at dry off with 100; 100 000 or 10 000 000 CFU of the udder-adapted S. chromogenes IM strain. Four quarters from one cow served as negative controls. Internally sealed quarters remained untouched, whereas non-sealed quarters were sampled 3 times during the dry period. After parturition, colostrum and daily milk samples were taken during the first week of lactation of all quarters. In total, 8 quarters appeared to be colonized, since S. chromogenes IM was recovered at least once during the experiment, as substantiated using Multilocus Sequence Typing. S. chromogenes IM shedding was highest in dry quarters inoculated with 10 000 000 CFU. Colonized quarters had the highest quarter somatic cell count (qSCC) in early lactation. Inoculated quarters (both colonized and non-colonized) had lower IL-6 and IL-10 concentrations in the dry period, whilst IFN-γ levels tended to be higher in colonized quarters compared to non-inoculated quarters. Also, IgG2 levels were higher in inoculated compared to non-inoculated quarters and the IgG2/IgG1 ratio was on average above 1. To conclude, we showed that dry quarters can be colonized with S. chromogenes IM, resulting in a shift towards a Th1 response in late gestation and early lactation characterised by an increased IgG2 concentration. However, further research is needed to confirm our findings.


Assuntos
Imunidade Inata , Mastite Bovina/microbiologia , Infecções Estafilocócicas/veterinária , Staphylococcus/fisiologia , Animais , Bovinos , Contagem de Células/veterinária , Feminino , Lactação , Mastite Bovina/imunologia , Infecções Estafilocócicas/imunologia , Infecções Estafilocócicas/microbiologia
3.
Vet Res ; 52(1): 114, 2021 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-34479647

RESUMO

Biofilm formation is a significant virulence factor in Staphylococcus (S.) aureus strains causing subclinical mastitis in dairy cows. A role of environmental signals and communication systems in biofilm development, such as the agr system in S. aureus, is suggested. In the context of multispecies biofilm communities, the presence of non-aureus staphylococci (NAS) might influence S. aureus colonization of the bovine mammary gland, yet, such interspecies interactions have been poorly studied. We determined whether 34 S. chromogenes, 11 S. epidermidis, and 14 S. simulans isolates originating from bovine milk samples and teat apices (TA) were able to affect biofilm formation and dispersion of S. aureus, and if so, how isolate traits such as the capacity to regulate the S. aureus agr quorum sensing system are determinants in this process. The capacity of an agr-positive S. aureus strain to form biofilm was increased more in the presence of S. chromogenes than in the presence of S. simulans and S. epidermidis isolates and in the presence of NAS isolates that do not harbor biofilm related genes. On the other hand, biofilm dispersion of this particular S. aureus strain was suppressed by NAS as a group, an effect that was more pronounced by isolates from TA. Furthermore, the observed effects on biofilm formation and dispersion of the agr-positive S. aureus strain as well as of an agr-negative S. aureus strain did not depend on the capacity of NAS to repress the agr system.


Assuntos
Proteínas de Bactérias/metabolismo , Biofilmes/crescimento & desenvolvimento , Doenças dos Bovinos/microbiologia , Percepção de Quorum , Infecções Estafilocócicas/veterinária , Staphylococcus/fisiologia , Transativadores/metabolismo , Animais , Bovinos , Infecções Estafilocócicas/microbiologia , Staphylococcus aureus/fisiologia
4.
Sci Rep ; 11(1): 17392, 2021 08 30.
Artigo em Inglês | MEDLINE | ID: mdl-34462461

RESUMO

Mastitis is a common and costly disease on dairy farms, commonly caused by Staphylococcus spp. though the various species are associated with different clinical outcomes. In the current study, we performed genomic analyses to determine the prevalence of adhesion, biofilm, and related regulatory genes in 478 staphylococcal species isolated from clinical and subclinical mastitis cases deposited in public databases. The most prevalent adhesin genes (ebpS, atl, pls, sasH and sasF) were found in both clinical and subclinical isolates. However, the ebpS gene was absent in subclinical isolates of Staphylococcus arlettae, S. succinus, S. sciuri, S. equorun, S. galinarum, and S. saprophyticus. In contrast, the coa, eap, emp, efb, and vWbp genes were present more frequently in clinical (vs. subclincal) mastitis isolates and were highly correlated with the presence of the biofim operon (icaABCD) and its transcriptional regulator, icaR. Co-phylogenetic analyses suggested that many of these adhesins, biofilm, and associated regulatory genes could have been horizontally disseminated between clinical and subclinical isolates. Our results further suggest that several adhesins, biofilm, and related regulatory genes, which have been overlooked in previous studies, may be of use for virulence profiling of mastitis-related Staphylococcus strains or as potential targets for vaccine development.


Assuntos
Adesinas Bacterianas/genética , Biofilmes/crescimento & desenvolvimento , Mastite Bovina/patologia , Infecções Estafilocócicas/patologia , Staphylococcus/genética , Animais , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Bovinos , Feminino , Mastite Bovina/microbiologia , Filogenia , Infecções Estafilocócicas/microbiologia , Staphylococcus/classificação , Staphylococcus/isolamento & purificação , Staphylococcus/fisiologia , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Fatores de Virulência/genética
5.
Meat Sci ; 181: 108613, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34218124

RESUMO

The use of protective cultures to inhibit spoilage bacteria is a promising natural preservation technique to extend the shelf-life of fresh meat. This study evaluated the effectiveness of six food-grade protective cultures (containing different combinations of Lactobacillus sakei, Pediococcus pentosaceus, Staphylococcus xylosus, and Staphylococcus carnosus) on naturally contaminated chill-stored (4 °C) lamb meat in different packaging systems. Only slight reductions of common meat spoilage bacteria Brochothrix thermosphacta, Pseudomonas spp., and Enterobacteriaceae were observed in culture-treated samples stored in modified atmosphere packaging (80% O2:20% CO2). Greater inhibitory effects were found in vacuum-packed lamb, with mixed cultures containing either L. sakei, S. carnosus, and S. xylosus or S. carnosus and L. sakei causing the most significant reductions. Protective cultures did not adversely affect meat color or pH. This study demonstrated the potential of protective cultures comprising lactic acid bacteria and coagulase-negative staphylococci in controlling microbial spoilage of lamb and, by inference, other types of meat as a natural solution for shelf-life extension.


Assuntos
Contagem de Colônia Microbiana , Embalagem de Alimentos/métodos , Conservação de Alimentos/métodos , Carne Vermelha/microbiologia , Animais , Atmosfera , Microbiologia de Alimentos , Lactobacillales/fisiologia , Ovinos , Staphylococcus/fisiologia , Vácuo
6.
Int J Mol Sci ; 22(12)2021 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-34200765

RESUMO

BacSp222 is a multifunctional peptide produced by Staphylococcus pseudintermedius 222. This 50-amino acid long peptide belongs to subclass IId of bacteriocins and forms a four-helix bundle molecule. In addition to bactericidal functions, BacSp222 possesses also features of a virulence factor, manifested in immunomodulatory and cytotoxic activities toward eukaryotic cells. In the present study, we demonstrate that BacSp222 is produced in several post-translationally modified forms, succinylated at the ε-amino group of lysine residues. Such modifications have not been previously described for any bacteriocins. NMR and circular dichroism spectroscopy studies have shown that the modifications do not alter the spatial structure of the peptide. At the same time, succinylation significantly diminishes its bactericidal and cytotoxic potential. We demonstrate that the modification of the bacteriocin is an effect of non-enzymatic reaction with a highly reactive intracellular metabolite, i.e., succinyl-coenzyme A. The production of succinylated forms of the bacteriocin depends on environmental factors and on the access of bacteria to nutrients. Our study indicates that the production of succinylated forms of bacteriocin occurs in response to the changing environment, protects producer cells against the autotoxicity of the excreted peptide, and limits the pathogenicity of the strain.


Assuntos
Bacteriocinas/química , Bacteriocinas/farmacologia , Macrófagos/efeitos dos fármacos , Neutrófilos/efeitos dos fármacos , Staphylococcus/fisiologia , Acil Coenzima A/metabolismo , Animais , Antibacterianos/farmacologia , Humanos , Lisina/química , Lisina/metabolismo , Macrófagos/patologia , Camundongos , Neutrófilos/patologia , Fragmentos de Peptídeos/química , Fragmentos de Peptídeos/farmacologia , Processamento de Proteína Pós-Traducional
7.
Sci Rep ; 11(1): 14473, 2021 07 14.
Artigo em Inglês | MEDLINE | ID: mdl-34262108

RESUMO

Stripe rust (caused by Puccinia striiformis tritici) is one of the most devastating diseases of wheat. The most effective ways to control stripe rust are the use of resistant cultivars and the timely use of an appropriate dose of fungicide. However, the changing nature of rust pathogen outwits the use of resistant cultivars, and the use of a fungicide is associated with environmental problems. To control the disease without sacrificing the environment, we screened 16 endophytic bacteria, which were isolated from stripe rust-resistant wheat cultivars in our previous study, for their biocontrol potential. A total of 5 bacterial strains Serratia marcescens 3A, Bacillus megaterium 6A, Paneibacillus xylanexedens 7A, Bacillus subtilis 11A, and Staphyloccus agentis 15A showed significant inhibition of Puccinia striiformis f. sp. tritici (Pst) urediniospores germination. Two formulations i.e., fermented liquid with bacterial cell (FLBC) and fermented liquid without bacterial cells (FL) of each bacterial strain, were evaluated against the urediniospores germination. Formulations of five selected endophytic bacteria strains significantly inhibited the uredinioospores germination in the lab experiments. It was further confirmed on seedlings of Pakistani susceptible wheat cultivar Inqilab-91 in the greenhouse, as well as in semi-field conditions. FLBC and FL formulations applied 24 h before Pst inoculation (hbi) displayed a protective mode. The efficacy of FLBC was between 34.45 and 87.77%, while the efficacy of FL was between 39.27 and 85.16% when applied 24 hbi. The inoculated wheat cultivar Inqilab-91 was also tested under semi-field conditions during the 2017-2018 cropping season at the adult plant stage. The strains Bacillus megaterium 6A and Paneibacillus xylanexedens 7A alone significantly reduced the disease severity of stripe rust with the efficacy of 65.16% and 61.11% for the FLBC in protective effect, while 46.07% and 44.47% in curative effect, respectively. Inoculated seedlings of Inqilab-91 showed higher activities of antioxidant enzymes, superoxide dismutase (SOD), peroxidase (POD), polyphenol oxidase (PPO), and phenylalanine ammonia-lyase (PAL). The treated seedlings also showed higher expressions of pathogenesis-related (PR) protein genes, antifungal protein (PR-1), ß-1,3-endoglucanases (PR-2), endochitinases (PR-4), peroxidase (PR-9), and ribonuclease-like proteins (PR-10). These results indicated that endophytic bacteria have the biocontrol potential, which can be used to manage stripe rust disease. High production antioxidant enzymes, as well as high expression of PR protein genes, might be crucial in triggering the host defense mechanism against Pst.


Assuntos
Agentes de Controle Biológico , Endófitos/fisiologia , Doenças das Plantas/microbiologia , Puccinia/patogenicidade , Plântula/microbiologia , Triticum/microbiologia , Bacillus megaterium/fisiologia , Bacillus subtilis/fisiologia , Enzimas/metabolismo , Regulação da Expressão Gênica de Plantas , Microscopia Eletrônica de Varredura , Células Vegetais/microbiologia , Folhas de Planta/microbiologia , Proteínas de Plantas/metabolismo , Serratia marcescens/fisiologia , Staphylococcus/fisiologia , Triticum/fisiologia
8.
J Dairy Res ; 88(2): 179-184, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33993898

RESUMO

Biofilm formation is a central feature to guarantee staphylococcal persistence in hosts and is associated with several diseases that are difficult to treat. In this research paper, biofilm formation and antimicrobial susceptibility were investigated in staphylococcal strains belonging to several species. These strains were isolated from the milk of cows with subclinical mastitis and most of them were coagulase-negative, with the prevalence of Staphylococcus chromogenes. High genetic diversity was observed among the strains by pulsed field gel electrophoresis. Antimicrobial resistance was assessed by disk diffusion and more than 50% of the strains were resistant to ampicillin and penicillin G, with multi-resistance profiles (13.6%) also being observed. Most strains (65.9%) formed biofilms when cultivated in BHI supplemented with 1% glucose. Most strains (72.7%) carried the intercellular adhesion gene (icaA), while less than half (36.3%) carried the biofilm-associated protein gene (bap). Concentrations of up to 10xMIC of erythromycin and tetracycline were not sufficient to suppress cell viability in preformed biofilms. Our results revealed that a genetically diverse group of biofilm-forming Staphylococcus species can be involved in subclinical mastitis. Since high antimicrobial concentrations cannot eradicate biofilm cells in vitro, their use in dairy animals may be ineffective in controlling infections, while supporting selection of resistant microorganisms. These data reinforce the need for alternative therapies aiming at disrupting biofilms for effective disease control.


Assuntos
Biofilmes/crescimento & desenvolvimento , Farmacorresistência Bacteriana/fisiologia , Mastite Bovina/microbiologia , Infecções Estafilocócicas/veterinária , Staphylococcus/efeitos dos fármacos , Staphylococcus/fisiologia , Animais , Antibacterianos/farmacologia , Proteínas de Bactérias/genética , Bovinos , Coagulase/análise , Farmacorresistência Bacteriana/genética , Feminino , Variação Genética , Mastite Bovina/tratamento farmacológico , Testes de Sensibilidade Microbiana/veterinária , Infecções Estafilocócicas/microbiologia , Staphylococcus/genética
9.
J Med Microbiol ; 70(5)2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-34048334

RESUMO

Introduction. Staphylococcus aureus (SA) and Staphylococcus epidermidis (SE) are the most common pathogens from the genus Staphylococcus causing biofilm-associated infections. Generally, biofilm-associated infections represent a clinical challenge. Bacteria in biofilms are difficult to eradicate due to their resistance and serve as a reservoir for recurring persistent infections.Gap Statement. A variety of protocols for in vitro drug activity testing against staphylococcal biofilms have been introduced. However, there are often fundamental differences. All these differences in methodical approaches can then be reflected in the form of discrepancies between results.Aim. In this study, we aimed to develop optimal conditions for staphylococcal biofilm formation on pegs. The impact of peg surface modification was also studied.Methodology. The impact of tryptic soy broth alone or supplemented with foetal bovine serum (FBS) or human plasma (HP), together with the impact of the inoculum density of bacterial suspensions and the shaking versus the static mode of cultivation, on total biofilm biomass production in SA and SE reference strains was studied. The surface of pegs was modified with FBS, HP, or poly-l-lysine (PLL). The impact on total biofilm biomass was evaluated using the crystal violet staining method and statistical data analysis.Results. Tryptic soy broth supplemented with HP together with the shaking mode led to crucial potentiation of biofilm formation on pegs in SA strains. The SE strain did not produce biofilm biomass under the same conditions on pegs. Preconditioning of peg surfaces with FBS and HP led to a statistically significant increase in biofilm biomass formation in the SE strain.Conclusion. Optimal cultivation conditions for robust staphylococcal biofilm formation in vitro might differ among different bacterial strains and methodical approaches. The shaking mode and supplementation of cultivation medium with HP was beneficial for biofilm formation on pegs for SA (ATCC 29213) and methicillin-resistant SA (ATCC 43300). Peg conditioning with HP and PLL had no impact on biofilm formation in either of these strains. Peg coating with FBS showed an adverse effect on the biofilm formation of these strains. By contrast, there was a statistically significant increase in biofilm biomass production on pegs coated with FBS and HP for SE (ATCC 35983).


Assuntos
Técnicas Bacteriológicas/instrumentação , Biofilmes/crescimento & desenvolvimento , Staphylococcus/fisiologia , Animais , Técnicas Bacteriológicas/métodos , Biofilmes/classificação , Biofilmes/efeitos dos fármacos , Biomassa , Meios de Cultura/química , Meios de Cultura/farmacologia , Matriz Extracelular de Substâncias Poliméricas/classificação , Matriz Extracelular de Substâncias Poliméricas/efeitos dos fármacos , Humanos , Especificidade da Espécie , Staphylococcus/classificação , Staphylococcus/efeitos dos fármacos
10.
Pol J Microbiol ; 70(1): 13-23, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33815523

RESUMO

Staphylococci are among the most frequent human microbiota components associated with the high level of bloodstream infection (BSI) episodes. In predisposed patients, there is a high risk of transformation of BSI episodes to sepsis. Both bacterial and host factors are crucial for the outcomes of BSI and sepsis. The highest rates of BSI episodes were reported in Africa, where these infections were up to twice as high as the European rates. However, there remains a great need to analyze African data for comprehensive quantification of staphylococcal BSI prevalence. The lowest rates of BSI exist in Australia. Asian, European, and North American data showed similar frequency values. Worldwide analysis indicated that both Staphylococcus aureus and coagulase-negative staphylococci (CoNS) are the most frequent BSI agents. In the second group, the most prevalent species was Staphylococcus epidermidis, although CoNS were not identified at the species level in many studies. The lack of a significant worldwide decrease in BSI episodes indicates a great need to implement standardized diagnostic methods and research etiological factors using advanced genetic methods.


Assuntos
Bacteriemia/microbiologia , Infecções Estafilocócicas/microbiologia , Staphylococcus/patogenicidade , África/epidemiologia , Animais , Bacteriemia/epidemiologia , Humanos , Infecções Estafilocócicas/epidemiologia , Staphylococcus/genética , Staphylococcus/isolamento & purificação , Staphylococcus/fisiologia , Virulência
11.
Bull Exp Biol Med ; 170(4): 458-460, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33713222

RESUMO

High biofilm-forming capacity of Staphylococcus spp. strains isolated from biomaterial of patients with infectious complications after primary knee replacement developed within 6-12 months after surgery was experimentally demonstrated. Differential leukocyte counts and some indicators of cell immunity in these patients were compared with those in patients without purulent complications and healthy volunteers. In patients with implant-associated infection, the relative numbers of T cells (both T-helpers and T-suppressors) B cells were significantly (p<0.05) reduced, while the number of NK cells was significantly increased in comparison with the corresponding parameters in other groups. The revealed changes attest to cell immunity failure in biofilm infection.


Assuntos
Biofilmes , Imunidade Celular/fisiologia , Linfócitos B/metabolismo , Voluntários Saudáveis , Humanos , Staphylococcus/imunologia , Staphylococcus/fisiologia , Staphylococcus epidermidis/imunologia , Staphylococcus epidermidis/fisiologia
12.
Int J Mol Sci ; 22(4)2021 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-33672958

RESUMO

Recent studies have reported that changes in gut microbiota composition could induce neuropsychiatric problems. In this study, we investigated alterations in gut microbiota induced by early-life stress (ELS) in rats subjected to maternal separation (MS; 6 h a day, postnatal days (PNDs) 1-21), along with changes in inflammatory cytokines and tryptophan-kynurenine (TRP-KYN) metabolism, and assessed the differences between sexes. High-throughput sequencing of the bacterial 16S rRNA gene showed that the relative abundance of the Bacteroides genus was increased and that of the Lachnospiraceae family was decreased in the feces of MS rats of both sexes (PND 56). By comparison, MS increased the relative abundance of the Streptococcus genus and decreased that of the Staphylococcus genus only in males, whereas the abundance of the Sporobacter genus was enhanced and that of the Mucispirillum genus was reduced by MS only in females. In addition, the levels of proinflammatory cytokines were increased in the colons (IFN-γ and IL-6) and sera (IL-1ß) of the male MS rats, together with the elevation of the KYN/TRP ratio in the sera, but not in females. In the hippocampus, MS elevated the level of IL-1ß and the KYN/TRP ratio in both male and female rats. These results indicate that MS induces peripheral and central inflammation and TRP-KYN metabolism in a sex-dependent manner, together with sex-specific changes in gut microbes.


Assuntos
Citocinas/metabolismo , Microbioma Gastrointestinal/fisiologia , Inflamação/metabolismo , Privação Materna , Estresse Psicológico/metabolismo , Animais , Animais Recém-Nascidos , Feminino , Microbioma Gastrointestinal/genética , Hipocampo/metabolismo , Inflamação/psicologia , Cinurenina/metabolismo , Masculino , Dinâmica Populacional , RNA Ribossômico 16S/genética , Ratos Sprague-Dawley , Fatores Sexuais , Staphylococcus/genética , Staphylococcus/fisiologia , Streptococcus/genética , Streptococcus/fisiologia , Estresse Psicológico/psicologia , Triptofano/metabolismo
13.
Vet Res ; 52(1): 34, 2021 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-33640030

RESUMO

Staphylococcus delphini is one of the most common pathogens isolated from mink infections, especially dermatitis. Tylosin (TYL) is used frequently against these infections, although no evidence-based treatment regimen exists. This study aimed to explore the dosage of TYL for infections caused by S. delphini in mink. Two animal experiments with a total of 12 minks were conducted to study the serum pharmacokinetic (PK) characteristics of TYL in mink after 10 mg/kg IV and oral dosing, respectively. The concentration of TYL in serum samples collected before and eight times during 24 h after TYL administration was quantitated with liquid chromatography quadrupole time-of-flight mass spectrometry, and the TYL disposition was analyzed using non-linear mixed effect analysis. The pharmacodynamics (PD) of TYL against S. delphini were studied using semi-mechanistic modeling of in vitro time-kill experiments. PKPD modeling and simulation were done to establish the PKPD index and dosage regimen. The disposition of TYL was described by a two-compartmental model. The area under the free concentration-time curve of TYL over the minimum inhibitory concentration of S. delphini (fAUC/MIC) was determined as PKPD index with breakpoints of 48.9 and 98.7 h for bacteriostatic and bactericidal effect, respectively. The calculated daily oral dose of TYL was 2378 mg/kg, which is 238-fold higher than the currently used TYL oral dosage regimen in mink (10 mg/kg). Accordingly, sufficient TYL concentrations are impossible to achieve in mink plasma, and use of this drug for extra-intestinal infections in this animal species must be discouraged.


Assuntos
Antibacterianos/farmacologia , Infecções Estafilocócicas/tratamento farmacológico , Staphylococcus/efeitos dos fármacos , Tilosina/farmacologia , Animais , Antibacterianos/farmacocinética , Masculino , Testes de Sensibilidade Microbiana/veterinária , Vison , Staphylococcus/fisiologia , Tilosina/farmacocinética
14.
Res Vet Sci ; 136: 138-142, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33621786

RESUMO

To detect methicillin resistant Staphylococcus aureus (MRSA) and S. pseudintermedius (MRSP) swab samples were collected from dogs, cats and horses from South East Queensland (SE QLD). MRSP carriage in dogs was 8.7% and no MRSP was isolated from cats and horses; no MRSA was isolated. Risk factors for carriage included previous hospitalisation, previous bacterial infection, consultation type, average precipitation, and human population density. The probability of MRSP carriage was highest in Brisbane city, Sunshine Coast and Gympie. This suggests that MRSP carriage in dog populations from SE QLD is geographically clustered and associated with clinical and environmental factors.


Assuntos
Doenças do Gato/epidemiologia , Doenças do Cão/epidemiologia , Doenças dos Cavalos/epidemiologia , Infecções Estafilocócicas/veterinária , Animais , Doenças do Gato/microbiologia , Gatos , Doenças do Cão/microbiologia , Cães , Feminino , Doenças dos Cavalos/microbiologia , Cavalos , Masculino , Resistência a Meticilina , Staphylococcus aureus Resistente à Meticilina/fisiologia , Queensland/epidemiologia , Infecções Estafilocócicas/epidemiologia , Infecções Estafilocócicas/microbiologia , Staphylococcus/fisiologia
15.
Sci Rep ; 11(1): 1157, 2021 01 13.
Artigo em Inglês | MEDLINE | ID: mdl-33442048

RESUMO

Staphylococcus schweitzeri belongs to the Staphylococcus aureus-related complex and is mainly found in African wildlife; no infections in humans are reported yet. Hence, its medical importance is controversial. The aim of this work was to assess the virulence of S. schweitzeri in vitro. The capacity of African S. schweitzeri (n = 58) for invasion, intra- and extracellular cytotoxicity, phagolysosomal escape, coagulase activity, biofilm formation and host cell activation was compared with S. aureus representing the most common clonal complexes in Africa (CC15, CC121, CC152). Whole genome sequencing revealed that the S. schweitzeri isolates belonged to five geographical clusters. Isolates from humans were found in two different clades. S. schweitzeri and S. aureus showed a similar host cell invasion (0.9 vs. 1.2 CFU/Vero cell), host cell activation (i.e. expression of pro-inflammatory cytokines, 4.1 vs. 1.7 normalized fold change in gene expression of CCL5; 7.3 vs. 9.9 normalized fold change in gene expression of IL8, A549 cells) and intracellular cytotoxicity (31.5% vs. 25% cell death, A549 cells). The extracellular cytotoxicity (52.9% vs. 28.8% cell death, A549 cells) was higher for S. schweitzeri than for S. aureus. Nearly all tested S. schweitzeri (n = 18/20) were able to escape from phagolysosomes. In conclusion, some S. schweitzeri isolates display virulence phenotypes comparable to African S. aureus. S. schweitzeri might become an emerging zoonotic pathogen within the genus Staphylococcus.


Assuntos
Infecções Estafilocócicas/patologia , Staphylococcus/patogenicidade , Células A549 , Animais , Linhagem Celular , Regulação da Expressão Gênica , Genoma Bacteriano , Haplorrinos , Interações Hospedeiro-Patógeno , Humanos , Filogenia , Infecções Estafilocócicas/genética , Staphylococcus/genética , Staphylococcus/fisiologia , Virulência
16.
BMJ Case Rep ; 14(1)2021 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-33495173

RESUMO

Surgery for prosthetic valve endocarditis in the mitral valve position is still challenging for surgeons. Reconstruction of the mitral annulus is useful for patients with a mitral annulus disputed by infection. Here, we report a redo mitral valve replacement using a collar-reinforced tissue valve, which was inserted into a mitral annulus reconstructed with a bovine patch. Though the preoperative blood culture detected Streptococcus anginosus, the intraoperative culture detected methicillin-resistant coagulase-negative staphylococci (MRCNS). MRCNS is rarely detected because of its indolent nature.


Assuntos
Antibacterianos/uso terapêutico , Endocardite Bacteriana/terapia , Implante de Prótese de Valva Cardíaca , Próteses Valvulares Cardíacas , Estenose da Valva Mitral/cirurgia , Infecções Relacionadas à Prótese/terapia , Infecções Estafilocócicas/terapia , Infecções Estreptocócicas/terapia , Idoso , Ampicilina/uso terapêutico , Hemocultura , Daptomicina/uso terapêutico , Desbridamento , Ecocardiografia , Endocardite Bacteriana/complicações , Endocardite Bacteriana/microbiologia , Feminino , Humanos , Embolia Intracraniana/diagnóstico por imagem , Embolia Intracraniana/etiologia , Imageamento por Ressonância Magnética , Resistência a Meticilina/fisiologia , Infecções Relacionadas à Prótese/microbiologia , Procedimentos Cirúrgicos Reconstrutivos , Reoperação , Staphylococcus/isolamento & purificação , Staphylococcus/fisiologia , Streptococcus anginosus/isolamento & purificação , Streptococcus anginosus/fisiologia , Sulbactam/uso terapêutico
17.
J Dairy Sci ; 104(1): 786-794, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33189273

RESUMO

Mastitis-causing pathogens are shed from infected mammary gland quarters and thus contribute to an increased risk of new intramammary infections. The objective of the current study was to investigate the shedding characteristics of various mastitis-causing pathogens and associated animal-specific (somatic cell score and parity) and environmental (heat stress) factors. In a longitudinal study, infected udder quarters were sampled consecutively on 5 dairy farms in Germany. To capture climatic factors, temperature-humidity index (THI) was calculated. In the laboratory analysis, the pathogens and their counts in the milk samples were determined. A generalized linear mixed model with gamma link was used to evaluate the factors influencing pathogen-shedding characteristics. The variables somatic cell count, pathogen, parity, and THI had significant influence on pathogen shedding. Staphylococci were shed in lower values than streptococci. The pathogen shedding from mammary gland quarters with intramammary infections was higher in the first and second lactation than in higher lactations. Exceeding the THI threshold 60 resulted in higher pathogen counts on the same day. This was only caused by the pathogens yeasts and Streptococcus uberis. Possible mechanisms causing differences in pathogen shedding are changes in the counts due to influenced milk quantities, better growth conditions at higher temperatures, or altered immunological reactions. The mechanisms often remain speculative and require further investigation. The study underlines the contribution of cows with high somatic cell counts regarding the transmission of mastitis pathogens within a herd. Furthermore, it becomes clear that heat stress in Germany influences udder health and that prevention measures are useful.


Assuntos
Derrame de Bactérias/fisiologia , Resposta ao Choque Térmico/fisiologia , Mastite Bovina/microbiologia , Animais , Bovinos , Contagem de Células/veterinária , Indústria de Laticínios , Feminino , Alemanha , Lactação , Leite/citologia , Leite/microbiologia , Paridade , Gravidez , Staphylococcus/fisiologia , Streptococcus/fisiologia
18.
Nat Prod Res ; 35(12): 2076-2081, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31397177

RESUMO

Juglans regia L. (common walnut) is a deciduous tree belonging to Juglandaceae family. Since ancient time, walnut was widely used in traditional medicine for its antioxidant, antidiabetic, antimicrobial, anti-inflammatory, anti-atherogenic and liver-protective effects. In this work, the antibacterial and anti-biofilm activities of walnuts pellicle extract against coagulase-negative staphylococci were evaluated. Qualitative chemical analysis was performed by the thin layer chromatography. UPLC-Ms/Ms was used to identify the chemical composition of J. regia extract. The total flavonoid and phenolic contents were determined by the Aluminium chloride and Folin-Ciocalteu methods, respectively. The extract showed antibacterial activity with MIC ranging from 3.60 to 461.75 µg/ml and MBC ranging from 461.75 to >461.75 µg/ml. Furthermore, it significantly reduced biofilm biomass and cell viability in a dose-dependent manner. Biological activities of J. regia extract may be due to its high flavonoid and phenolic contents. The obtained results are promising and they deserve further scientific investigations.


Assuntos
Antibacterianos/farmacologia , Juglans/química , Extratos Vegetais/farmacologia , Staphylococcus/efeitos dos fármacos , Antibacterianos/administração & dosagem , Antibacterianos/química , Biofilmes/efeitos dos fármacos , Cromatografia Líquida , Coagulase/análise , Relação Dose-Resposta a Droga , Flavonoides/análise , Nozes/química , Fenóis/análise , Extratos Vegetais/administração & dosagem , Extratos Vegetais/análise , Extratos Vegetais/química , Plantas Medicinais/química , Staphylococcus/fisiologia , Espectrometria de Massas em Tandem
19.
Eur J Med Res ; 25(1): 48, 2020 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-33046122

RESUMO

BACKGROUND: Coagulase-negative staphylococcus (CoNS) is considered to be the major reservoirs for genes facilitating the evolution of S. aureus as a successful pathogen. The present study aimed to determine the occurrence of genes conferring resistance to fluoroquinolone, determining of the prevalence of insertion sequence elements IS256, IS257 and different superantigens (SAgs) among CoNS isolates obtained from various clinical sources. MATERIALS AND METHODS: The current study conducted on a total of the 91 CoNS species recovered from clinical specimens in Hamadan hospitals in western Iran in 2017-2019. The antimicrobial susceptibility testing was performed using disk diffusion method and the presence of the IS256 and IS257, genes conferring resistance to fluoroquinolone and enterotoxins/enterotoxin-like encoding genes were investigated by polymerase chain reaction (PCR) method. RESULTS: Among genes encoding classic enterotoxins, sec was the most frequent which was carried by 48.4% of the 91 isolates, followed by seb in 27.5% of the isolates. None of the CoNS isolates was found to be positive to enterotoxin-like encoding genes. In 11(12%) of all isolates that were phenotypically resistant to levofloxacin, 9 isolates (81.8%) were positive for gyrB, 8 isolates (72.7%) were positive for gyrA, 8 isolates (72.7%) harbored grlB and 7 isolates (63.6%) were found to carry grlA. The IS256 and IS257 were identified in 31.8% and 74.7% of the isolates, respectively. The results of statistical analysis showed a significant association between the occurrence of staphylococcal enterotoxins (SEs) encoding genes and antimicrobial resistance. CONCLUSION: Antimicrobial resistant determinants and SEs are co-present in clinical CoNS isolates that confer selective advantage for colonization and survival in hospital settings. The coexistence of insertion elements and antibiotic resistance indicate their role in pathogenesis and infectious diseases.


Assuntos
Coagulase/genética , Farmacorresistência Bacteriana/genética , Enterotoxinas/genética , Genes Bacterianos/genética , Staphylococcus/genética , Antibacterianos/farmacologia , Coagulase/metabolismo , Fluoroquinolonas/farmacologia , Humanos , Irã (Geográfico)/epidemiologia , Testes de Sensibilidade Microbiana , Reação em Cadeia da Polimerase , Prevalência , Especificidade da Espécie , Infecções Estafilocócicas/tratamento farmacológico , Infecções Estafilocócicas/epidemiologia , Infecções Estafilocócicas/microbiologia , Staphylococcus/classificação , Staphylococcus/fisiologia
20.
Sci Rep ; 10(1): 14525, 2020 09 03.
Artigo em Inglês | MEDLINE | ID: mdl-32884012

RESUMO

Kawasaki disease (KD) is a multi-systemic vasculitis of unknown etiology that occurs mainly in children, and the disturbance of gut microbiota is generally believed to cause a hyperimmune reaction triggering KD. The aim of the study was to investigate the alterations in the fecal microbiota and assess its relationship with systemic inflammation. Totally 30 KD children were enrolled and followed up for 6 months, with another group of 30 age- and sex-matched healthy children as controls. Phylotype profiles of fecal microbial communities were analyzed using 16S rRNA gene sequencing. Serum inflammatory markers were detected by flow cytometer. We showed that KD children exhibited a significant reduction in fecal microbial diversity in the acute phase compared with the healthy controls. Enterococcus, Acinetobacter, Helicobacter, Lactococcus, Staphylococcus and Butyricimonas in acute KD children were significantly higher than the healthy children. Levels of systemic inflammation biomarkers, including IL-2, IL-4, IL-6, IL-10, TNF-α, and INF-γ, were significantly elevated in the acute KD children. Altered microbiota genera Enterococcus and Helicobacter abundances were shown to be correlated positively with IL-6, which were never previously reported in KD. This study suggested that gut microbiota alteration is closely associated with systemic inflammation, which provides a new perspective on the etiology and pathogenesis of KD.


Assuntos
Inflamação/imunologia , Inflamação/microbiologia , Síndrome de Linfonodos Mucocutâneos/imunologia , Síndrome de Linfonodos Mucocutâneos/microbiologia , Acinetobacter/fisiologia , Pré-Escolar , Biologia Computacional , Enterococcus/fisiologia , Feminino , Microbioma Gastrointestinal/fisiologia , Helicobacter/fisiologia , Humanos , Lactente , Inflamação/metabolismo , Lactococcus/fisiologia , Masculino , Síndrome de Linfonodos Mucocutâneos/metabolismo , Reação em Cadeia da Polimerase , Staphylococcus/fisiologia
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