Tenebrio molitor as a model system to study Staphylococcus spp virulence and horizontal gene transfer.

Invertebrates can provide a valuable alternative to traditional vertebrate animal models for studying bacterial and fungal infections. This study aimed to establish the larvae of the coleoptera Tenebrio molitor (mealworm) as an in vivo model for evaluating virulence and horizontal gene transfer between Staphylococcus spp. After identifying the best conditions for rearing T.

The Presence of Virulent and Multidrug-Resistant Clones of Carbapenem-Resistant Klebsiella pneumoniae in Southeastern Brazil.

The emergence of carbapenem-resistant Klebsiella pneumoniae (CRKP) represents an urgent threat to global public health due to the limited therapeutic options available to control this pathogen. This study aims to analyze the molecular epidemiology, antimicrobial resistance and virulence profile of CRKP isolated from patients at hospitals in Southeastern Brazil. KPC and other beta-lactamase genes were detected in all strains, which were also multidrug-resistant (MDR).

Interspecies transfer of plasmid-borne gentamicin resistance between Staphylococcus isolated from domestic dogs to Staphylococcus aureus.

As preconized by the One Health concept, the intimate relationship between pets and owners is a common source for the trade of microorganisms with zoonotic potential, and with them, antimicrobial resistance genes. In this work, we evaluated the presence of antimicrobial resistance genes, that are usually within mobile genetic elements, in a laboratory collection of 79 canine Staphylococcus strains, mostly Staphylococcus pseudintermedius and Staphylococcus coagulans. Resistance to tetracycline was observed in 34% of the strains, followed by resistance to erythromycin (21%) and gentamicin (19%).

Epigallocatechin gallate has antibacterial and antibiofilm activity in methicillin resistant and susceptible of different lineages in non-cytotoxic concentrations.

is an opportunistic agent that can cause a variety of infections, both hospital and community-acquired. Epigallocatechin gallate (EGCG), a flavonoid present in the leaves of , has different biological activities, including antimicrobial potential. Here we evaluate the antibacterial and antibiofilm potential of EGCG in nine clinical strains of with different genetic profile and antimicrobial susceptibilities.

Evaluation of antimicrobial potential and surface morphology in thin films of titanium nitride and calcium phosphate on orthodontic brackets.

Introduction: The goal of this research was to experimentally evaluate the surface morphology and adhesion capacity of Streptococcus mutans (U159) on brackets with thin films of titanium nitride (TN) and of titanium nitride doped with calcium phosphate (TNCP).

Methods: Twenty-four metallic brackets were equally allocated to 3 groups (n = 8), according to the type of covering (no covering, TNCP, and TN). The coatings were deposited by cathodic cage (TNCP and TN groups) and were evaluated by scanning electron microscopy and energy dispersive x-ray spectrometry.

Overview of rearing and testing conditions and a guide for optimizing Galleria mellonella breeding and use in the laboratory for scientific purposes.

The greater wax moth Galleria mellonella is an increasingly popular and consolidated alternative infection model to assess microbial virulence and the effectiveness of antimicrobial compounds. The lack of G. mellonella suppliers aiming at scientific purposes and a lack of well-established protocols for raising and testing these animals may impact results and reproducibility between different laboratories.

Galleria mellonella as an infection model: an in-depth look at why it works and practical considerations for successful application.

The larva of the greater wax moth Galleria mellonella is an increasingly popular model for assessing the virulence of bacterial pathogens and the effectiveness of antimicrobial agents. In this review, we discuss details of the components of the G. mellonella larval immune system that underpin its use as an alternative infection model, and provide an updated overview of the state of the art of research with G.

Underrated Staphylococcus species and their role in antimicrobial resistance spreading.

The increasing threat of antimicrobial resistance has shed light on the interconnection between humans, animals, the environment, and their roles in the exchange and spreading of resistance genes. In this review, we present evidences that show that Staphylococcus species, usually referred to as harmless or opportunistic pathogens, represent a threat to human and animal health for acting as reservoirs of antimicrobial resistance genes. The capacity of genetic exchange between isolates of different sources and species of the Staphylococcus genus is discussed with emphasis on mobile genetic elements, the contribution of biofilm formation, and evidences obtained either experimentally or through genome analyses.

Typical and Atypical Enteroaggregative Are Both Virulent in the Model.

Enteroaggregative (EAEC) is an emerging pathotype responsible for acute and persistent diarrhea. It can be classified as typical and atypical strains, respectively, based on the presence or absence of the AggR regulon, suggesting a higher virulence for typical EAEC. This study aims to evaluate in the model if there are differences in the virulence profiles among clinical strains of typical and atypical EAEC, prototype strains EAEC C1096, 042 and its mutant.

Differences in resistance profiles and virulence genes among methicillin-resistant and methicillin-susceptible Staphylococcus aureus of different lineages at a public tertiary hospital.

Introduction: Staphylococcus aureus is a major nosocomial pathogen that is associated with high virulence and the rapid development of drug resistance.

Methods: We analyzed and compared the antimicrobial resistance, virulence profiles, and molecular epidemiology of 67 S. aureus strains, including 36 methicillin-sensitive (MSSA) and 31 methicillin-resistant (MRSA) strains recovered from a public hospital located in south-eastern Brazil.

Antimicrobial resistance, biofilm formation and virulence reveal Actinobacillus pleuropneumoniae strains' pathogenicity complexity.

Porcine pleuropneumonia is an important cause of lowered productivity and economic loss in the pig industry worldwide, associated primarily with Actinobacillus pleuropneumoniae infection. Its colonization and persistence within the upper respiratory tract of affected pigs depends upon interactions between a number of genetically controlled virulence factors, such as pore-forming repeats-in-toxin exoproteins, biofilm formation, and antimicrobial resistance. This study investigated correlations between biofilm-forming capacity, antimicrobial resistance, and virulence of A.

Clonal dissemination of vancomycin-resistant Enterococcus faecium ST412 in a Brazilian region.

Vancomycin-resistant Enterococcus faecium (VREfm) has emerged as an important global nosocomial pathogen, and this trend is associated with the spread of high-risk clones. Here, we determined the genetic and phenotypic features of 93 VREfm isolates that were obtained from patients in 13 hospitals in Vitória, Espírito Santo, Brazil, during 2012-2013. All the isolates were vancomycin-resistant and harbored the vanA gene.

Differential cellular immune response of Galleria mellonella to Actinobacillus pleuropneumoniae.

In the present work, we have investigate the cellular immune response of Galleria mellonella larvae against three strains of the gram-negative bacterium Actinobacillus pleuropneumoniae: low-virulence (780), high-virulence (1022) and the serotype 8 reference strain (R8). Prohemocytes, plasmatocytes, granulocytes, oenocytoids and spherulocytes were distinguished according to their size and morphology, their molecular markers and dye-staining properties and their role in the immune response. Total hemocyte count, differential hemocyte count, lysosome activity, autophagic response, cell viability and caspase-3 activation were determined in circulating hemocytes of naive and infected larvae.

Draft Genome Sequences of Six Actinobacillus pleuropneumoniae Serotype 8 Brazilian Clinical Isolates: Insight into New Applications.

Actinobacillus pleuropneumoniae is the causative agent of swine pleuropneumonia, a highly contagious disease associated with pigs of all ages that results in severe economic losses to the industry. Here, we report for the first time six genome sequences of A. pleuropneumoniae clinical isolates of serotype 8, found worldwide.

Galleria mellonella is an effective model to study Actinobacillus pleuropneumoniae infection.

Actinobacillus pleuropneumoniae is responsible for swine pleuropneumonia, a respiratory disease that causes significant global economic loss. Its virulence depends on many factors, such as capsular polysaccharides, RTX toxins and iron-acquisition systems. Analysis of virulence may require easy-to-use models that approximate mammalian infection and avoid ethical issues.

Beginning to understand the role of sugar carriers in Colletotrichum lindemuthianum: the function of the gene mfs1.

Fungi of the Colletotrichum genus are among the most prominent phytopathogens that cause diseases with a considerable economic impact, such as anthracnose. The hemibiotrophic fungus Colletotrichum lindemuthianum (teleomorph Glomerella cingulata f. sp.