Dengue is an emerging disease of high impact on human health. Plants are an important source of new antivirals and stands for its biological properties. The aim of this study was to evaluate the cytotoxicity and antiviral activity and elucidate the antiviral mechanism of ethanolic extracts from against dengue virus 2 (DENV-2).
View Article and Find Full Text PDFThe aim of this study was to evaluate the activation pathway(s) triggered by Minthostachys verticillata essential oil (EO) in bovine mammary epithelial cells (MAC-T) challenged with a strain of bovine Staphylococcus aureus. MAC-T cells were stimulated with EO, S. aureus or pre-treated with EO and then challenged with S.
View Article and Find Full Text PDFThe use of antimicrobials in the dairy production environment for mastitis control must take etiology, clinical signs, economic impacts, and regulatory frameworks into consideration. The objective of the present review is to highlight important aspects of the dynamics of antimicrobial use in dairy production and the potential impacts on the main pathogens circulating in this environment, considering the parameters set by the World Health Organization (WHO) regarding the priority of monitoring as well as control strategies for these agents, such as the methicillin-resistant and the beta-lactamase-producing . Understanding the animal-environment-pathogen triad is crucial for establishing control measures and preventing the spread of bacterial resistance.
View Article and Find Full Text PDFDesign of innovative adjuvant strategies with an appropriate safety profile is relevant to developed subunit or inactivated microorganism vaccines for bovine mastitis. Minthostachys verticillata essential oil (EO) has demonstrated ability to stimulate the innate immune response and adjuvant effect similar to Al(OH). Here we evaluated the adjuvant effect of EO and its metabolite, limonene (L) alone and microencapsulated by spray-drying, using an inactivated Enterococcus faecium strain bovine-mastitis inducer.
View Article and Find Full Text PDFAim: Nine Streptococcus uberis strains with different biofilm-forming profiles in relation to their capacity of adherence and invasion to MAC-T cell lines were examined. Additionally, virulence genes were also linked to adherence and invasion.
Methods And Results: All S.
The efficacy of certain vaccines is improved by the use of adjuvants. Nowadays, the development of new, effective, and safe adjuvants that stimulate the innate immune response is researched. In this context, medicinal plants appear as a suitable alternative.
View Article and Find Full Text PDFA wide variety of contagious and environmental bacteria can cause bovine mastitis worldwide. Antibiotic therapy is currently used for the treatment of the disease, although its intensive use leads to the emergence of resistant strains. Bacteriocins arise as potential antibacterial option for mastitis treatment.
View Article and Find Full Text PDFBovine mastitis causes large annual economic losses around the world. Different microorganisms are associated with the disease. The capacity of pathogens to adhere to bovine mammary epithelial cells is associated with biofilm production which leads to antibiotic resistance.
View Article and Find Full Text PDFThe pathogenesis of Streptococcus uberis is attributed to a combination of extracellular factors and properties such as adherence and biofilm formation. The aim of this work was to evaluate the influence of different factors, additives and bovine milk compounds on S. uberis biofilm formation, as the presence of the sua gene by PCR.
View Article and Find Full Text PDFBovine mastitis is a disease that causes great economic losses per year, being Streptococcus uberis the main environmental pathogen involved. The aim of the present study was to determine the minimum inhibitory concentration (MIC) and the minimum bactericidal concentration (MBC) of Minthostachys verticillata essential oil and limonene for S. uberis strains isolated from bovine mastitis.
View Article and Find Full Text PDFCoagulase-negative staphylococci (CNS) are a common cause of bovine subclinical mastitis (SCM). The prevalence of CNS species causing SCM identified by genotyping varies among countries. Overall, the antimicrobial resistance in this group of organisms is increasing worldwide; however, little information exists about a CNS species resistant to antibiotics.
View Article and Find Full Text PDFBiochem Mol Biol Educ
July 2016
In this article, we describe a basic practical laboratory designed for fifth-year undergraduate students of Microbiology as part of the Epidemiology course. This practice provides the students with the tools for molecular epidemiological analysis of pathogenic microorganisms using a rapid and simple PCR technique. The aim of this work was to assay RAPD-PCR technique in order to infer possible epidemiological relationships.
View Article and Find Full Text PDFRev Argent Microbiol
October 2015
The aim of this study was to evaluate the genotypic relationships among 40 Streptococcus uberis isolated from bovine mastitis by using pulsed-field gel electrophoresis (PFGE). Additionally, the association between PFGE patterns and virulence profiles was investigated. The isolates exhibited 17 PFGE patterns.
View Article and Find Full Text PDFMinthostachys verticillata (peperina) is an aromatic and medicinal plant with several uses and ethnobotanical properties. Numerous studies have demonstrated that its essential oil (Mv-EO) presents antimicrobial capacity and shows immunomodulating and anti-allergic properties in human cell lines. Thus, the goal of this study was to investigate the main chemical composition, analyzed by GC-FID, and the cyto-genotoxic effects of Mv-EO, using Vero cells, human PBMCs and mice bone marrow cells.
View Article and Find Full Text PDFThe aim of this study was to investigate the phenotypic and genotypic characteristics of Streptococcus uberis isolated from subclinical mastitis (SCM) cases, and to examine the possible association between both characteristics. A total of 32 S. uberis were isolated from 772 quarter milk samples (SCM > 250,000 cells/ml) collected from 195 cows selected randomly from 18 dairy farms located in Argentina.
View Article and Find Full Text PDFIn a previous study we have demonstrated that cold aqueous extract of Baccharis articulata (Ba-CAE) induced the death of human peripheral blood mononuclear cells (PBMCs) and exerted low mutagenic effects on mice at 6h after administration. The aim of this work was to investigate whether the PBMCs death induced by Ba-CAE is due to apoptosis, and whether this extract exerts mutagenic effects on mice at 24 and 48h after administration. In addition, Ba-CAE was chemically characterized.
View Article and Find Full Text PDFStreptococcus uberis is a major environmental mastitis-causing pathogen. The infections are predominantly subclinical and are frequently undetected and untreated for extended periods of time. More information about the pathogenesis of S.
View Article and Find Full Text PDFStreptococcus uberis is an important pathogen that has been implicated in bovine mastitis but the virulence factors associated with pathogenesis are not well understood. The aim of this work was to examine 11 putative and known virulence-associated genes by PCR in 78 S. uberis strains isolated from infected animals in Argentina.
View Article and Find Full Text PDFMost veterinary and milk hygiene laboratories identify streptococci and enterococci based on serological and biochemical tests. The analysis of 16S rDNA was suggested to be used for more exact identification; however, its use has not been considered so far in monitoring studies. The objective of the present study was to compare a conventional phenotypic method with restriction fragment length polymorphism analysis of 16S rDNA (16S rDNA RFLP) for identification of streptococci isolated from composite milk samples collected in connection with intramammary infection (IMI) in six Argentinean dairy farms.
View Article and Find Full Text PDFHumans are a natural reservoir of Staphylococcus aureus and asymptomatic colonization is far more common than infection. The aim of this work was to characterize genotypically 68 S. aureus strains isolated from nasal swabs of healthy people and from human clinical infections.
View Article and Find Full Text PDFStaphylococcus aureus is one of the most important pathogens in humans and animals. In this study eighty strains were analyzed by RAPD-PCR to assess the genetic relationship between S. aureus isolates from bovine and human hosts.
View Article and Find Full Text PDFStaphylococcus aureus is the main etiological agent of bovine mastitis. Intramammary infections are difficult to cure and vaccination appears to be an alternative to prevent the disease. Research has focused on the development of mutants affected in the synthesis of pathogenicity determinants.
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