Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 23.074
Filtrar
1.
BMJ Case Rep ; 14(5)2021 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-34045192

RESUMO

A 78-year-old man with an implantable cardioverter-defibrillator (ICD) presented with chills and malaise. His history was significant for heart failure with reduced ejection fraction and complete heart block. He had undergone permanent pacemaker placement that was later upgraded to an ICD 5 years before his presentation. Physical examination revealed an open wound with surrounding erythema overlying the device site. Blood cultures obtained on admission were negative. Transesophageal echocardiogram did not show valve or lead vegetations. He underwent a prolonged extraction procedure. Postoperatively, he developed septic shock and cultures from the device, and repeat peripheral blood cultures grew Staphylococcus simulans and Staphylococcus epidermidis He was treated with intravenous vancomycin but had refractory hypotension, leading to multiorgan failure. He later expired after being transitioned to comfort care. The patient may have acquired S. simulans by feeding cows on a nearby farm, and the prolonged extraction procedure may have precipitated the bacteraemia.


Assuntos
Bacteriemia , Desfibriladores Implantáveis , Sepse , Idoso , Animais , Bacteriemia/tratamento farmacológico , Bacteriemia/etiologia , Bovinos , Desfibriladores Implantáveis/efeitos adversos , Humanos , Masculino , Staphylococcus
2.
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
3.
Int J Mol Sci ; 22(8)2021 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-33921909

RESUMO

In this study, as a measure to enhance the antimicrobial activity of biomaterials, the selenium ions have been substituted into hydroxyapatite (HA) at different concentration levels. To balance the potential cytotoxic effects of selenite ions (SeO32-) in HA, strontium (Sr2+) was co-substituted at the same concentration. Selenium and strontium-substituted hydroxyapatites (Se-Sr-HA) at equal molar ratios of x Se/(Se + P) and x Sr/(Sr + Ca) at (x = 0, 0.01, 0.03, 0.05, 0.1, and 0.2) were synthesized via the wet precipitation route and sintered at 900 °C. The effect of the two-ion concentration on morphology, surface charge, composition, antibacterial ability, and cell viability were studied. X-ray diffraction verified the phase purity and confirmed the substitution of selenium and strontium ions. Acellular in vitro bioactivity tests revealed that Se-Sr-HA was highly bioactive compared to pure HA. Se-Sr-HA samples showed excellent antibacterial activity against both Gram-negative (Escherichia coli) and Gram-positive (Staphylococcus carnosus) bacterial strains. In vitro cell-material interaction, using human osteosarcoma cells MG-63 studied by WST-8 assay, showed that Se-HA has a cytotoxic effect; however, the co-substitution of strontium in Se-HA offsets the negative impact of selenium and enhanced the biological properties of HA. Hence, the prepared samples are a suitable choice for antibacterial coatings and bone filler applications.


Assuntos
Antibacterianos/síntese química , Antibacterianos/farmacologia , Hidroxiapatitas/química , Selênio/química , Estrôncio/química , Antibacterianos/efeitos adversos , Antibacterianos/química , Sobrevivência Celular/efeitos dos fármacos , Staphylococcus/efeitos dos fármacos
4.
BMC Ophthalmol ; 21(1): 157, 2021 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-33789630

RESUMO

BACKGROUND: Staphylococcus-associated marginal keratitis is an immune-mediated corneal disorder mainly secondary to chronic blepharoconjunctivitis. We report a rare case of Staphylococcus-associated marginal keratitis following pterygium excision. To the best of our knowledge, none of the previous literature has described such an acute complication after pterygium surgery. CASE PRESENTATION: We report a case of a 50-year-old woman who suffered from pterygium in the left eye and underwent pterygium surgery. After surgery, slit-lamp examination showed an incomplete ring-shaped creamy white infiltrate. Corneal pathogenic microbial detection was negative. Staphylococcus aureus was found on the upper eyelid margin of the affected eye. Therefore, she was clinically diagnosed with Staphylococcus-associated marginal keratitis. The infiltrate was gradually absorbed after steroids, topical antibiotics, and lubricant eye drops were administered. After 2 years of follow-up, neither corneal infiltrate nor pterygium recurrence was observed. CONCLUSION: Staphylococcus-associated marginal keratitis is an immune reaction mainly secondary to chronic blepharoconjunctivitis, which usually activates an antigen-antibody reaction with complementary activation and neutrophil infiltration in patients sensitized to staphylococcal antigens. Early detection and treatment is of great importance. Topical steroids are effective and should be initiated early once pathogenic microbial infections are excluded. Although chronic staphylococcal blepharoconjunctivitis is a common disease, ophthalmologists should pay more attention to it to avoid potential complications.


Assuntos
Infecções Oculares Bacterianas , Ceratite , Pterígio , Infecções Estafilocócicas , Infecções Oculares Bacterianas/diagnóstico , Infecções Oculares Bacterianas/tratamento farmacológico , Infecções Oculares Bacterianas/etiologia , Feminino , Humanos , Ceratite/diagnóstico , Ceratite/etiologia , Pessoa de Meia-Idade , Pterígio/cirurgia , Infecções Estafilocócicas/diagnóstico , Infecções Estafilocócicas/etiologia , Staphylococcus
5.
Medicine (Baltimore) ; 100(16): e25623, 2021 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-33879734

RESUMO

ABSTRACT: Microbiota has been suggested to play a role in patients with intestinal and cutaneous diseases. However, the profiling of perianal eczema microbiota has not been described. We have explored the general profile and possible differences between acute and chronic perianal eczema. A total of 101 acute perianal eczema (APE) and 156 chronic perianal eczema (CPE) patients were enrolled in this study and the perianal microbiota was profiled via Illumina sequencing of the 16S rRNA V4 region.The microbial α-diversity and structure are similar in APE and CPE patients; however, the perianal microbiota of the APE patients had a higher content of Staphylococcus (22.2%, P < .01) than that of CPE patients. Top10 genera accounting for more than 60% (68.81% for APE and 65.47% for CPE) of the whole microbiota, including Prevotella, Streptococcus, and Bifidobacterium, show an upregulation trend in the case of APE without reaching statistically significant differences. This study compared the microbiota profiles of acute and chronic perianal eczema. Our results suggest that the microbiota of acute perianal eczema patients is enriched in Staphylococcus compared with that in the chronic group. Our findings provide data for further studies.


Assuntos
Doenças do Ânus/microbiologia , Eczema/microbiologia , Microbiota , Doença Aguda , Adulto , Canal Anal/microbiologia , Bifidobacterium/isolamento & purificação , Doença Crônica , Contagem de Colônia Microbiana , Feminino , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Masculino , RNA Ribossômico 16S/análise , Pele/microbiologia , Staphylococcus/isolamento & purificação , Streptococcus/isolamento & purificação
6.
Sensors (Basel) ; 21(5)2021 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-33800145

RESUMO

Rapid point of care tests for bacterial infection diagnosis are of great importance to reduce the misuse of antibiotics and burden of antimicrobial resistance. Here, we have successfully combined a new class of non-biological binder molecules with electrochemical impedance spectroscopy (EIS)-based sensor detection for direct, label-free detection of Gram-positive bacteria making use of the specific coil-to-globule conformation change of the vancomycin-modified highly branched polymers immobilized on the surface of gold screen-printed electrodes upon binding to Gram-positive bacteria. Staphylococcus carnosus was detected after just 20 min incubation of the sample solution with the polymer-functionalized electrodes. The polymer conformation change was quantified with two simple 1 min EIS tests before and after incubation with the sample. Tests revealed a concentration dependent signal change within an OD600 range of Staphylococcus carnosus from 0.002 to 0.1 and a clear discrimination between Gram-positive Staphylococcus carnosus and Gram-negative Escherichia coli bacteria. This exhibits a clear advancement in terms of simplified test complexity compared to existing bacteria detection tests. In addition, the polymer-functionalized electrodes showed good storage and operational stability.


Assuntos
Técnicas Biossensoriais , Vancomicina , Bactérias , Espectroscopia Dielétrica , Técnicas Eletroquímicas , Eletrodos , Ouro , Polímeros , Staphylococcus
7.
Mikrobiyol Bul ; 55(2): 125-145, 2021 Apr.
Artigo em Turco | MEDLINE | ID: mdl-33882647

RESUMO

Biofilms are often responsible for the difficulties in the treatment of infectious diseases due to their properties that facilitate escape from antibiotic effect and their antiphagocytic effects. At least 65% of all infectious diseases are associated with biofilm-forming bacteria. As Staphylococcus aureus and Staphylococcus epidermidis are among the most common agents of hospital infections and the infections are mostly biofilm-related, they pose an important problem. In infectious isolates, the minimum biofilm eradication concentration (MBEK) values of biofilm forms are much higher than the minimum inhibition concentration (MIC) values of planktonic forms. This situation requires the use of much higher doses of antibiotics in the treatment of infections and causes an increase in antibiotic resistance. The N-acetylcysteine (NAC) molecule is known to be effective against biofilm by disrupting mature biofilms and reducing the adhesion of bacteria to surfaces. In this study, it was aimed to demonstrate i) the biofilm-forming abilities ii) the change in ampicillin and vancomycin MIC values in the presence of NAC molecules, iii) the change in the MBEK values of these antibiotics in the presence of NAC molecule and iv) the change in the expression levels of genes thought to be related to biofilm formation in the presence of the NAC molecule among S.aureus (n= 38) and S.epidermidis (n= 12) isolates isolated from various clinical specimens in Trakya University Health Research and Application Center. In this study, microplate crystal violet method was used to demonstrate the biofilm formation in staphylococci. Broth microdilution and checkerboard method were used to demonstrate the change in the presence of NAC molecule of the MIC and MBEC values of ampicillin and vancomycin. The effect of NAC on the expression of intercellular binding proteins A and D (icaA, icaD) and Staphylococcus regulatory protein A (sarA) genes, which are the genes involved in biofilm formation in staphylococci, was determined by quantitative real-time Polymerase Chain Reaction (qRt-PCR) method. The Student-t test was used to compare the control and experimental groups (concentrations detected with synergy and additive effect); p˂ 0.05 was accepted as the limit value of significance. In this study, when the NAC molecule was used together with ampicillin and vancomycin, it was determined that this combination lowers the MIC values of staphylococcus isolates and staphylococcal biofilm MBEK values; and also the expression levels of icaA, icaD and sarA which were effective in biofilm formation in staphylococci have not changed and decreased. As a result, in this study, it has been determined that the NAC molecule can be a new alternative for combined drug therapy and is promising in terms of bringing a new approach to treatment. In addition, it is thought that it is possible to use the NAC molecule together with different microorganisms and antimicrobial agents, and the results obtained in this study are considered to be guiding for further studies on this subject.


Assuntos
Antibacterianos , Infecções Estafilocócicas , Antibacterianos/farmacologia , Biofilmes , Humanos , Testes de Sensibilidade Microbiana , Infecções Estafilocócicas/tratamento farmacológico , Staphylococcus/genética , Vancomicina/farmacologia
8.
J Med Microbiol ; 70(3)2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33704043

RESUMO

Introduction. Coagulase-negative staphylococci have been recognized both as emerging pathogens and contaminants of clinical samples. High-resolution genomic investigation may provide insights into their clinical significance.Aims. To review the literature regarding coagulase-negative staphylococcal infection and the utility of genomic methods to aid diagnosis and management, and to identify promising areas for future research.Methodology. We searched Google Scholar with the terms (Staphylococcus) AND (sequencing OR (infection)). We prioritized papers that addressed coagulase-negative staphylococci, genomic analysis, or infection.Results. A number of studies have investigated specimen-related, phenotypic and genetic factors associated with colonization, infection and virulence, but diagnosis remains problematic.Conclusion. Genomic investigation provides insights into the genetic diversity and natural history of colonization and infection. Such information allows the development of new methodologies to identify and compare relatedness and predict antimicrobial resistance. Future clinical studies that employ suitable sampling frames coupled with the application of high-resolution whole-genome sequencing may aid the development of more discriminatory diagnostic approaches to coagulase-staphylococcal infection.


Assuntos
Coagulase/deficiência , Genômica , Infecções Estafilocócicas/microbiologia , Staphylococcus/genética , Staphylococcus/isolamento & purificação , Adaptação Fisiológica/genética , Bacteriemia/diagnóstico , Bacteriemia/microbiologia , Farmacorresistência Bacteriana/genética , Humanos , Infecções Relacionadas à Prótese/diagnóstico , Infecções Relacionadas à Prótese/microbiologia , Infecções Estafilocócicas/diagnóstico , Infecções Estafilocócicas/transmissão , Staphylococcus/enzimologia , Staphylococcus/patogenicidade , Virulência/genética
9.
Klin Lab Diagn ; 66(2): 115-121, 2021 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-33734646

RESUMO

A comparative analysis of the quality of the developed nutrient media, Baird-Parker dry agar base and Vogel-Johnson dry agar Base and foreign analogues, was done based on results of clinical trials. The tested media were qualified by the main biological parameters, such as sensitivity, growth rate, and differentiating and inhibiting properties. The evaluation of statistical reliability of the results of trials of clinical samples was evaluated taking into account the number of parallel studies and the number of matches of the results of studies conducted by different performers. 116 clinical samples of received by a laboratory of the testing laboratory center for research from hospital no.164 over the period of clinical trials were analyzed. 46 cultures of potential pathogens were isolated when culturing on test and control media: S. aureus -35; S. epidermidis-6; S. saprophyticus - 5. Lecithinase activity on the medium "Baird-Parker dry agar Base" and mannitol fermentation on the medium "Vogel-Johnson dry agar Base" in the preliminary phenotypic test allow the isolation and differentiation of clinical isolates of S. aureus from S. epidermidis, and S. saprophyticus.


Assuntos
Staphylococcus aureus , Staphylococcus , Ágar , Meios de Cultura , Humanos , Reprodutibilidade dos Testes
10.
Int J Food Microbiol ; 345: 109154, 2021 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-33735783

RESUMO

A novel killer toxin produced by yeast Metschnikowia pulcherrima was purified and added into ready to cook meatballs to enhance their microbial safety and extension of their shelf life. The agent was added into ready to cook meatballs at two different concentrations (1%-K1 and 2%-K2). The results of those two groups were compared to the control group (K0) lacking the killer toxin. Physical, chemical and microbiological analyses were carried out in meat dough and all analyses were repeated at two day intervals during 10 day-storage at +4 °C. Addition of inhibitor compound in meat dough decreased the numbers of total aerobic mesophillic bacteria, yeast and molds and lactic acid bacteria. Staphylococci/Micrococci, coliform bacteria and total psychrotrophic bacterial counts of the samples were determined as well. Results showed that all indicators of microbial deterioration were found to be higher in K1 group than K2 group, revealing that there was an inverse correlation between the concentration of killer toxin and the number of microorganisms causing spoilage. In addition to 1 log decrease in the number of microorganisms in toxin added groups, the high TBARS values of the control group also showed the effectiveness of the toxin. Toxic effect analysis results showed that the killer toxin had no toxic effect on L929 mouse fibroblast cells after 24h exposure.


Assuntos
Antibacterianos/farmacologia , Enterobacteriaceae/efeitos dos fármacos , Metschnikowia/metabolismo , Micotoxinas/farmacologia , Staphylococcus/efeitos dos fármacos , Animais , Bovinos , Linhagem Celular , Contagem de Colônia Microbiana , Armazenamento de Alimentos , Carne/microbiologia , Camundongos
11.
J Dairy Sci ; 104(5): 6061-6079, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33685704

RESUMO

The objective of this prospective cohort study was to explore associations between intramammary infection (IMI) in late-lactation cows and postcalving udder health and productivity. Cows (n = 2,763) from 74 US dairy herds were recruited as part of a previously published cross-sectional study of bedding management and IMI in late-lactation cows. Each herd was visited twice for sampling. At each visit, aseptic quarter milk samples were collected from 20 cows approaching dry-off (>180 d pregnant), which were cultured using standard bacteriological methods and MALDI-TOF for identification of isolates. Quarter-level culture results were used to establish cow-level IMI status at enrollment. Cows were followed from enrollment until 120 d in milk (DIM) in the subsequent lactation. Herd records were used to establish whether subjects experienced clinical mastitis or removal from the herd, and DHIA test-day data were used to record subclinical mastitis events (somatic cell count >200,000 cells/mL) and milk yield (kg/d) during the follow-up period. Cox regression and generalized estimating equations were used to evaluate the associations between IMI and the outcome of interest. The presence of late-lactation IMI caused by major pathogens was positively associated with postcalving clinical mastitis [hazard ratio = 1.5, 95% confidence interval (CI): 1.2, 2.0] and subclinical mastitis (risk ratio = 1.5, 95% CI: 1.3, 1.9). Species within the non-aureus Staphylococcus (NAS) group varied in their associations with postcalving udder health, with some species being associated with increases in clinical and subclinical mastitis in the subsequent lactation. Late-lactation IMI caused by Streptococcus and Streptococcus (Strep)-like organisms, other than Aerococcus spp. (i.e., Enterococcus, Lactococcus, and Streptococcus spp.) were associated with increases in postcalving clinical and subclinical mastitis. Test-day milk yield from 1 to 120 DIM was lower (-0.9 kg, 95% CI: -1.6, -0.3) in late-lactation cows with any IMI compared with cows without IMI. No associations were detected between IMI in late lactation and risk for postcalving removal from the herd within the first 120 DIM. Effect estimates reported in this study may be less than the underlying quarter-level effect size for IMI at dry-off and postcalving clinical and subclinical mastitis, because of the use of late-lactation IMI as a proxy for IMI at dry-off and the use of cow-level exposure and outcome measurements. Furthermore, the large number of models run in this study (n = 94) increases the chance of identifying chance associations. Therefore, confirmatory studies should be conducted. We conclude that IMI in late lactation may increase risk of clinical and subclinical mastitis in the subsequent lactation. The relationship between IMI and postcalving health and productivity is likely to vary among pathogens, with Staphylococcus aureus, Streptococcus spp., Enterococcus spp., and Lactococcus spp. being the most important pathogens identified in the current study.


Assuntos
Aerococcus , Doenças dos Bovinos , Mastite Bovina , Animais , Bovinos , Contagem de Células/veterinária , Estudos Transversais , Enterococcus , Feminino , Lactação , Lactococcus , Glândulas Mamárias Animais , Leite , Gravidez , Estudos Prospectivos , Staphylococcus , Streptococcus
12.
Nat Commun ; 12(1): 1887, 2021 03 25.
Artigo em Inglês | MEDLINE | ID: mdl-33767207

RESUMO

Coagulase-negative staphylococci and Staphylococcus aureus colonize similar niches in mammals and conceivably compete for space and nutrients. Here, we report that a coagulase-negative staphylococcus, Staphylococcus chromogenes ATCC43764, synthesizes and secretes 6-thioguanine (6-TG), a purine analog that suppresses S. aureus growth by inhibiting de novo purine biosynthesis. We identify a 6-TG biosynthetic gene cluster in S. chromogenes and other coagulase-negative staphylococci including S. epidermidis, S. pseudintermedius and S. capitis. Recombinant S. aureus strains harbouring this operon produce 6-TG and, when used in subcutaneous co-infections in mice with virulent S. aureus USA300, protect the host from necrotic lesion formation. Used prophylactically, 6-TG reduces necrotic skin lesions in mice infected with USA300, and this effect is mediated by abrogation of toxin production. RNAseq analyses reveal that 6-TG downregulates expression of genes coding for purine biosynthesis, the accessory gene regulator (agr) and ribosomal proteins in S. aureus, providing an explanation for its effect on toxin production.


Assuntos
Infecções Cutâneas Estafilocócicas/tratamento farmacológico , Staphylococcus aureus/crescimento & desenvolvimento , Staphylococcus/genética , Staphylococcus/metabolismo , Tioguanina/metabolismo , Animais , Proteínas de Bactérias/biossíntese , Coagulase/deficiência , Feminino , Camundongos , Camundongos Endogâmicos BALB C , Purinas/biossíntese , Proteínas Ribossômicas/biossíntese , Staphylococcus aureus/patogenicidade , Staphylococcus capitis/metabolismo , Staphylococcus epidermidis/metabolismo , Tioguanina/farmacologia , Transativadores/biossíntese
13.
Carbohydr Polym ; 259: 117716, 2021 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-33673992

RESUMO

We report on a procedure for the preparation, printing and curing of antibacterial poly(N-isopropylacrylamide) nanocellulose-reinforced hydrogels. These composites present a highly anisotropic microstructure which allows to control and modulate the resulting mechanical properties. The incorporation of such nanoparticles enables us to modify both the strength and the humidity-dependent swelling direction of printed parts, offering a fourth-dimensional property to the resulting composite. Antibacterial properties of the hydrogels were obtained by incorporating the functionalized peptide ε-polylysine, modified with the addition of a methacrylate group to ensure UV-immobilization. We highlight the relevance of well-adapted viscoelastic properties of our material for 3D printing by direct ink writing of self-supporting complex structures reaching inclination angles of 45°. The addition of cellulose nanoparticles, the overall ink composition and the printing parameters strongly determine the resulting degree of orientation. The achieved control over the anisotropic swelling properties paves the way to complex three-dimensional structures with programmable actuation.


Assuntos
Antibacterianos/química , Celulose/química , Hidrogéis/química , Nanopartículas/química , Resinas Acrílicas/química , Antibacterianos/farmacologia , Força Compressiva , Escherichia coli/efeitos dos fármacos , Hidrogéis/farmacologia , Tinta , Impressão Tridimensional , Reologia , Staphylococcus/efeitos dos fármacos
14.
J Dairy Sci ; 104(4): 4604-4614, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33685714

RESUMO

This study aimed to determine the occurrence of methicillin-resistant (MR) non-aureus staphylococci (NAS) on 20 preselected German dairy farms. Farms were selected based on the detection of methicillin-resistant Staphylococcus aureus (MRSA) during previous diagnostic investigations. Bacterial culture of presumptive MR-NAS was based on a 2-step enrichment method that has been recommended for MRSA detection. Quarter milk samples (QMS), bulk tank milk, swab samples from young stock, and environmental samples were collected for bacterial culture. Methicillin-resistant NAS were detected on all study farms. The MR-NAS positive test rate was 3.3% (77/2,347) in QMS, 42.1% (8/19) in bulk tank milk, 29.1% (59/203) in nasal swabs from milk-fed calves, 18.3% (35/191) in postweaning calves, and 7.3% (14/191) in nasal swabs from prefresh heifers. In the environment, MR-NAS were detected in dust samples on 25% (5/20) of the dairy farms as well as in teat liners and suckers from automatic calf feeders. The geometric mean somatic cell count in QMS affected by MR-NAS (183,000 cells/mL) was slightly higher compared with all QMS (114,000 cells/mL). Nine MR-NAS species were identified; Staph. sciuri, Staph. lentus, Staph. fleurettii, Staph. epidermidis, and Staph. haemolyticus were the most common species. In addition, 170 NAS isolates were identified that showed reduced cefoxitin susceptibility (4 mg/L) but did not harbor the mecA or mecC genes. On some farms, similar mobile genetic elements were detected in MR-NAS and MRSA. It was suggested that resistance genes may be transferred between NAS and Staph. aureus on the respective farms.


Assuntos
Doenças dos Bovinos , Staphylococcus aureus Resistente à Meticilina , Infecções Estafilocócicas , Animais , Bovinos , Fazendas , Feminino , Resistência a Meticilina , Testes de Sensibilidade Microbiana/veterinária , Leite , Infecções Estafilocócicas/veterinária , Staphylococcus
15.
BMJ Case Rep ; 14(3)2021 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-33692047

RESUMO

Staphylococcus pseudintermedius is a common cause of zoonotic infections in dogs and cats. Recently, there has been an increasing number of infections being reported in humans caused by this organism. We report a case of complicated urinary tract infection in an elderly patient with recent bilateral ureteral stent placement caused by this organism with associated persistent high-grade bacteraemia.


Assuntos
Doenças do Gato , Doenças do Cão , Infecções Estafilocócicas , Infecções Urinárias , Idoso , Animais , Antibacterianos/uso terapêutico , Doenças do Gato/tratamento farmacológico , Gatos , Cães , Humanos , Infecções Estafilocócicas/tratamento farmacológico , Staphylococcus , Infecções Urinárias/tratamento farmacológico
16.
Nucleic Acids Res ; 49(7): 4008-4019, 2021 04 19.
Artigo em Inglês | MEDLINE | ID: mdl-33721016

RESUMO

The compact CRISPR/Cas9 system, which can be delivered with their gRNA and a full-length promoter for expression by a single adeno-associated virus (AAV), is a promising platform for therapeutic applications. We previously identified a compact SauriCas9 that displays high activity and requires a simple NNGG PAM, but the specificity is moderate. Here, we identified three compact Cas9 orthologs, Staphylococcus lugdunensis Cas9 (SlugCas9), Staphylococcus lutrae Cas9 (SlutrCas9) and Staphylococcus haemolyticus Cas9 (ShaCas9), for mammalian genome editing. Of these three Cas9 orthologs, SlugCas9 recognizes a simple NNGG PAM and displays comparable activity to SaCas9. Importantly, we generated a SlugCas9-SaCas9 chimeric nuclease, which has both high specificity and high activity. We finally engineered SlugCas9 with mutations to generate a high-fidelity variant that maintains high specificity without compromising on-target editing efficiency. Our study offers important minimal Cas9 tools that are ideal for both basic research and clinical applications.


Assuntos
Proteínas de Bactérias , Proteína 9 Associada à CRISPR/genética , Sistemas CRISPR-Cas , Staphylococcus , Proteínas de Bactérias/genética , Fibroblastos , Edição de Genes , Células HEK293 , Células HeLa , Humanos , Staphylococcus/genética
17.
J Dairy Sci ; 104(5): 5979-5987, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33663831

RESUMO

Mastitis is an important problem in meat-producing sheep, but few studies have investigated the transmission dynamics of mastitis pathogens in these animals. The objective of this study was to describe the pathogens causing intramammary infections (IMI) in suckler ewes, their effect on somatic cell count, and the dynamics of these IMI in early lactation. We enrolled 15 sheep flocks early after lambing and selected ewes in each flock that were sampled twice with a 3-wk interval. Milk samples from both glands of each ewe were bacteriologically cultured, and somatic cell count was measured. Non-aureus Staphylococcus spp. were the most prevalent culture results. Somatic cell counts were most strongly increased in ewes infected with Mannheimia haemolytica, whereas staphylococci, including Staphylococcus aureus, were associated with a moderate increase in somatic cell count. The proportion of udder halves that remained culture-positive with Staphylococcus spp. during the 3-wk sampling interval was moderate, but M. haemolytica infections were stable during this time period. A substantial number of new infections were seen in the early lactation study period for non-aureus Staphylococcus spp., Staph. aureus, and Corynebacterium spp., but not for M. haemolytica or Streptococcus spp. The number of new IMI of Staph. aureus was associated with the number of Staph. aureus-infected udder halves in the flock at the first sampling moment, indicative of contagious transmission. Altogether, we show that substantial transmission happens in early lactation in suckler ewes, but that the dynamics differ between pathogen species. More research is needed to further describe transmission in different stages of lactation and to identify transmission routes, to develop effective interventions to control mastitis.


Assuntos
Mastite , Infecções Estafilocócicas , Animais , Contagem de Células/veterinária , Feminino , Lactação , Glândulas Mamárias Animais , Mastite/veterinária , Leite , Ovinos , Infecções Estafilocócicas/veterinária , Staphylococcus
18.
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
19.
BMC Genomics ; 22(1): 102, 2021 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-33541265

RESUMO

BACKGROUND: Staphylococcus and Streptococcus species can cause many different diseases, ranging from mild skin infections to life-threatening necrotizing fasciitis. Both genera consist of commensal species that colonize the skin and nose of humans and animals, and of which some can display a pathogenic phenotype. RESULTS: We compared 235 Staphylococcus and 315 Streptococcus genomes based on their protein domain content. We show the relationships between protein persistence and essentiality by integrating essentiality predictions from two metabolic models and essentiality measurements from six large-scale transposon mutagenesis experiments. We identified clusters of strains within species based on proteins associated to similar biological processes. We built Random Forest classifiers that predicted the zoonotic potential. Furthermore, we identified shared attributes between of Staphylococcus aureus and Streptococcus pyogenes that allow them to cause necrotizing fasciitis. CONCLUSIONS: Differences observed in clustering of strains based on functional groups of proteins correlate with phenotypes such as host tropism, capability to infect multiple hosts and drug resistance. Our method provides a solid basis towards large-scale prediction of phenotypes based on genomic information.


Assuntos
Fasciite Necrosante , Infecções Estreptocócicas , Animais , Fasciite Necrosante/genética , Humanos , Fenótipo , Staphylococcus/genética , Streptococcus pyogenes
20.
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
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...