Publications by authors named "Rosa M Silva"

This study explores the bioactive potential of banana leaf extracts and their innovative integration into knitted hemp fabrics. To obtain the extracts, distinct extraction methodologies were employed, namely conventional extraction, ultrasound-assisted extraction, and pressurized-liquid extraction. Aqueous and hydroethanolic solvents, namely 20% (/) and 50% (/), were employed during the extraction process.

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Article Synopsis
  • The study focused on EC092, a strain of bacteria isolated from bloodstream infections that shows hybrid pathogenic potential due to its enteroaggregative (EAEC) genetic markers.
  • Whole-genome sequencing identified EC092 as belonging to phylogroup B1, ST278, and serotype O165:H4, revealing several genes associated with virulence factors, including fimbriae and toxins.
  • The strain EC092 was found to have a similar virulence profile to some EAEC strains linked to diarrhea and is capable of causing infections outside the intestines, indicating its dual pathogenic capabilities.
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Extra-intestinal pathogenic (ExPEC) may inhabit the human gut microbiota without causing disease. However, if they reach extra-intestinal sites, common cystitis to bloodstream infections may occur, putting patients at risk. To examine the human gut as a source of endogenous infections, we evaluated the clonal diversity of 18 inpatients' guts and their relationship with strains isolated from urinary tract infection (UTI) in the same hospital.

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Extraintestinal pathogenic Escherichia coli (ExPEC) is the leading cause of urinary tract infection worldwide and a critical bloodstream infection agent. There are more than 50 virulence factors (VFs) related to ExPEC pathogenesis; however, many strains isolated from extraintestinal infections are devoid of these factors. Since opportunistic infections may occur in immunocompromised patients, E.

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Several strategies are used by to evade the host innate immune system in the blood, such as the cleavage of complement system proteins by secreted proteases. Members of the Serine Proteases Autotransporters of Enterobacteriaceae (SPATE) family have been described as presenting proteolytic effects against complement proteins. Among the SPATE-encoding genes (secreted autotransporter toxin) has been detected in high frequencies among strains of isolated from bacteremia.

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Urinary tract infections (UTI) affect community and healthcare patients worldwide and may have different clinical outcomes. We assessed the phylogenetic origin, the presence of 43 virulence factors (VFs) of diarrheagenic and extraintestinal pathogenic , and the occurrence of hybrid strains among isolates from 172 outpatients with different types of UTI. Isolates from phylogroup B2 (46%) prevailed, followed by phylogroups A (15.

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Extraintestinal pathogenic Escherichia coli (ExPEC) is a leading cause of human and animal infections worldwide. The utilization of selective and differential media to facilitate the isolation and identification of E. coli from complex samples, such as water, food, sediment, and gut tissue, is common in epidemiological studies.

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Hybrid strains of combine virulence traits of diarrheagenic (DEC) and extraintestinal pathogenic (ExPEC), but it is poorly understood whether these combined features improve the virulence potential of such strains. We have previously identified a uropathogenic (UPEC) strain (UPEC 252) harboring the gene that encodes the adhesin intimin and is located in the locus of enterocyte effacement (LEE) pathogenicity island. The LEE-encoded proteins allow enteropathogenic (EPEC) and enterohemorrhagic (EHEC) to form attaching and effacing (A/E) lesions in enterocytes.

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Although extraintestinal pathogenic (ExPEC) are designated by their isolation site and grouped based on the type of host and the disease they cause, most diarrheagenic (DEC) are subdivided into several pathotypes based on the presence of specific virulence traits directly related to disease development. This scenario of a well-categorized collapsed after the German outbreak of 2011, caused by one strain bearing the virulence factors of two different DEC pathotypes (enteroaggregative and Shiga toxin-producing ). Since the outbreak, many studies have shown that this phenomenon is more frequent than previously realized.

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Escherichia coli EC121 is a multidrug-resistant (MDR) strain isolated from a bloodstream infection of an inpatient with persistent gastroenteritis and T-zone lymphoma that died due to septic shock. Despite causing an extraintestinal infection, previous studies showed that it did not have the usual characteristics of an extraintestinal pathogenic Instead, it belonged to phylogenetic group B1 and harbored few known virulence genes. To evaluate the pathogenic potential of strain EC121, an extensive genome sequencing and in vitro characterization of various pathogenicity-associated properties were performed.

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is an important pathogen responsible for a variety of diseases. We have recently shown that Pic, a serine protease secreted by , mediates immune evasion by the direct cleavage of complement molecules. The aim of this study was to investigate the action of a Pic-producing bacteria in a murine model of sepsis.

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Extraintestinal pathogenic Escherichia coli (ExPEC) is the major cause of Gram-negative-related sepsis. Bacterial survival in the bloodstream is mediated by a variety of virulence traits, including those mediating immune system evasion. Serine protease autotransporters of Enterobacteriaceae (SPATE) constitute a superfamily of virulence factors that can cause tissue damage and cleavage of molecules of the complement system, which is a key feature for the establishment of infection in the bloodstream.

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Uropathogenic (UPEC) strains are responsible for most cases of urinary tract infections worldwide. We present the draft whole-genome sequence of the UPEC 252 strain, which carries the gene that encodes the intimin adhesin. Intimin promotes intimate adherence of enteropathogenic and enterohemorrhagic to intestinal cells.

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We characterize by whole-plasmid-sequence (WPS) two-plasmid-borne obtained from (Asp-1069) and (Acb-45063) clinical strains recovered 17 years apart from distinct Brazilian regions. Multilocus sequence type (MLST) analysis showed that the Asp-1069 and Acb-45063 strains belong to ST551 and ST15/CC15, respectively. WPS analysis demonstrated that was located in two distinct plasmids named pAs1069_a (24,672 bp/44 open reading frames [ORFs]) and pAb45063_b (19,808 bp/24 ORFs), which belong to the GR8/GR23 () and GR4 () incompatibility groups, respectively.

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Escherichia albertii are emerging enteropathogens, whose identification is difficult, as they share biochemical characteristics and some virulence-related genes with diarrheagenic Escherichia coli (DEC). Studies on phylogeny, phenotypic characteristics and potential virulence factors of human E. albertii strains are scarce.

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Enteroaggregative Escherichia coli (EAEC) has been recently associated with urinary tract infections (UTI). Since EAEC are found in feces of both diarrheic and asymptomatic individuals, their presence in the intestine may be a source of UTI. In this study, we detected in feces of diarrheic and healthy children a subset of EAEC strains with genetic markers of extraintestinal pathogenic E.

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Here we report the draft genome sequence of a multidrug-resistant (MDR) Aeromonas hydrophila strain belonging to sequence type 508 (ST508) isolated from a human bloodstream infection. Assembly and annotation of this draft genome resulted in 5028498bp and revealed the presence of 16S rRNA methylase rmtD and bla genes encoding high-level resistance to aminoglycosides and cephalosporins, respectively, as well as multiple virulence genes. This draft genome can provide significant information for understanding mechanisms on the establishment and treatment of infections caused by this pathogen.

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Perceptual judgments are an essential mechanism for our everyday interaction with other moving agents or events. For instance, estimation of the time remaining before an object contacts or passes us is essential to act upon or to avoid that object. Previous studies have demonstrated that participants use different cues to estimate the time to contact or the time to passage of approaching visual stimuli.

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Background: Enteroinvasive Escherichia coli (EIEC) may be the causative agent of part of those million cases of diarrhea illness reported worldwide every year and attributable to Shigella. That is because both enteropathogens have many common characteristics that difficult their identification either by traditional microbiological methods or by molecular tools used in the clinical laboratory settings. While Shigella has been extensively studied, EIEC remains barely characterized at the molecular level.

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Background: In a previous study, we detected the presence of a Mycobacterium avium species-specific insertion sequence, IS1245, in Mycobacterium kansasii. Both species were isolated from a mixed M. avium-M.

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Four of six adhesin-encoding genes (lpfA, paa, iha, and toxB) from Shiga toxin-producing Escherichia coli strains were detected in typical and atypical enteropathogenic E. coli (EPEC) strains of various serotypes. Although the most prevalent gene was lpfA in both groups, paa was the only potential diarrhea-associated gene in atypical EPEC.

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Mycobacterium kansasii carrying IS1245, a highly prevalent insertion sequence among Mycobacterium avium isolates, was detected in a mixed culture of M. avium and M. kansasii.

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The presence of the pathogenicity island (PAI) O122 genes, efa1 (lifA), sen, pagC, nleB, and nleE, in typical and atypical enteropathogenic Escherichia coli (EPEC) strains was investigated. The simultaneous occurrence of all genes was statistically associated with diarrhea due to atypical EPEC. Detection of the complete PAI O122 could aid in the identification of potential pathogenic strains of atypical EPEC.

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Enteropathogenic Escherichia coli (EPEC) forms attaching and effacing lesions in the intestinal mucosa characterized by intimate attachment to the epithelium by means of intimin (an outer membrane adhesin encoded by eae). EPEC is subgrouped into typical (tEPEC) and atypical (aEPEC); only tEPEC carries the EAF (EPEC adherence factor) plasmid that encodes the bundle-forming pilus (BFP). Characteristically, after 3 h of incubation, tEPEC produces localized adherence (LA) (with compact microcolonies) in HeLa/HEp-2 cells by means of BFP, whereas most aEPEC form looser microcolonies.

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