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We investigated bile salts' ability to induce phenotypic changes in biofilm production and protein expression of pathogenic Escherichia coli strains. For this purpose, 82 pathogenic E. coli strains isolated from humans (n = 70), and animals (n = 12), were examined for their ability to form biofilms in the presence or absence of bile salts. We also identified bacterial proteins expressed in response to bile salts using sodium dodecyl-sulfate polyacrylamide gel electrophoresis (SDS-electrophoresis) and liquid chromatography-mass spectrometry (LC-MS/MS). Lastly, we evaluated the ability of these strains to adhere to Caco-2 epithelial cells in the presence of bile salts. Regarding biofilm formation, two strains isolated from an outbreak in Republic of Georgia in 2009 were the only ones that showed a high and moderate capacity to form biofilm in the presence of bile salts. Further, we observed that those isolates, when in the presence of bile salts, expressed different proteins identified as outer membrane proteins (i.e. OmpC), and resistance to adverse growth conditions (i.e. F0F1, HN-S, and L7/L12). We also found that these isolates exhibited high adhesion to epithelial cells in the presence of bile salts. Together, these results contribute to the phenotypic characterization of E. coli O104: H4 strains.
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Infecções por Escherichia coli , Escherichia coli O104 , Proteínas de Escherichia coli , Escherichia coli Shiga Toxigênica , Animais , Humanos , Escherichia coli/metabolismo , Virulência , Células CACO-2 , Cromatografia Líquida , Espectrometria de Massas em Tandem , Biofilmes , Infecções por Escherichia coli/microbiologia , Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/metabolismoRESUMO
The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the etiological agent responsible for the coronavirus disease 2019 (COVID-19). The high rate of mutation of this virus is associated with a quick emergence of new viral variants that have been rapidly spreading worldwide. Several mutations have been documented in the receptor-binding domain (RBD) of the viral spike protein that increases the interaction between SARS-CoV-2 and its cellular receptor, the angiotensin-converting enzyme 2 (ACE2). Mutations in the spike can increase the viral spread rate, disease severity, and the ability of the virus to evade either the immune protective responses, monoclonal antibody treatments, or the efficacy of current licensed vaccines. This review aimed to highlight the functional virus classification used by the World Health Organization (WHO), Phylogenetic Assignment of Named Global Outbreak (PANGO), Global Initiative on Sharing All Influenza Data (GISAID), and Nextstrain, an open-source project to harness the scientific and public health potential of pathogen genome data, the chronological emergence of viral variants of concern (VOCs) and variants of interest (VOIs), the major findings related to the rate of spread, and the mutations in the spike protein that are involved in the evasion of the host immune responses elicited by prior SARS-CoV-2 infections and by the protection induced by vaccination.
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COVID-19 , SARS-CoV-2 , Humanos , Mutação , Filogenia , Ligação Proteica , SARS-CoV-2/genética , Glicoproteína da Espícula de CoronavírusRESUMO
Asparaginase (ASNase) is a widely applied chemotherapeutic drug that is used to treat Acute Lymphoblastic Leukemia (ALL); however, immune responses and silent inactivation of the drug often limit its bioavailability. Many strategies have been proposed to overcome these drawbacks, including the development of improved formulations (biobetters), but only two of them are currently on the market. Nano- and micro-encapsulation are some of the most promising and novel approaches to enhance in vivo performance of ASNase, preventing the direct contact of the enzyme with the environment, protecting it from protease degradation, increasing the enzymes catalytic half-life, and in some cases, reducing immunogenicity. This review summarizes the strategies, particularly for ASNase nano- and micro-encapsulation, and their main findings, constraints, and current gaps in the state-of-the-art knowledge. The pros and cons of the use of different nanocarriers are discussed with the idea to ultimately provide safer and more effective treatments for patients with ALL.
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BACKGROUND: Melioidosis is an infectious disease caused by Burkholderia pseudomallei. In Mexico, the disease is rarely diagnosed in humans and there is no evidence of simultaneous environmental isolation of the pathogen. Here, we describe clinical profiles of fatal cases of melioidosis in two children, in a region without history of that disease. CASE PRESENTATION: About 48 h before onset of symptoms, patients swam in a natural body of water, and thereafter they rapidly developed fatal septicemic illness. Upon necropsy, samples from liver, spleen, lung, cerebrospinal fluid, and bronchial aspirate tissues contained Burkholderia pseudomallei. Environmental samples collected from the locations where the children swam also contained B. pseudomallei. All the clinical and environmental strains showed the same BOX-PCR pattern, suggesting that infection originated from the area where the patients were swimming. CONCLUSIONS: The identification of B. pseudomallei confirmed that melioidosis disease exists in Sonora, Mexico. The presence of B. pseudomallei in the environment may suggest endemicity of the pathogen in the region. This study highlights the importance of strengthening laboratory capacity to prevent and control future melioidosis cases.
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Melioidose/complicações , Pneumonia Bacteriana/etiologia , Adolescente , Burkholderia pseudomallei/isolamento & purificação , Criança , Evolução Fatal , Feminino , Humanos , Masculino , Melioidose/diagnóstico , Melioidose/patologia , Melioidose/fisiopatologia , México , Pneumonia Bacteriana/diagnóstico , Pneumonia Bacteriana/patologia , Pneumonia Bacteriana/fisiopatologia , Sepse/microbiologia , NataçãoRESUMO
We report an analysis of the genomic diversity of isolates of Burkholderia pseudomallei, the cause of melioidosis, recovered in Colombia from routine surveillance during 2016-2017. B. pseudomallei appears genetically diverse, suggesting it is well established and has spread across the region.
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Burkholderia pseudomallei , Melioidose , Burkholderia pseudomallei/genética , Colômbia/epidemiologia , Genômica , Humanos , Melioidose/epidemiologia , Tipagem de Sequências MultilocusRESUMO
Background: Perceptions of asthma triggers provide important guidance for patients' disease management. A psychometrically valid instrument, the Asthma Trigger Inventory (ATI), is available in English and German language versions, however, a version in Spanish as major world language has been missing.Method: A Spanish-language version of the ATI was evaluated in 339 adult patients with asthma, 223 of these in Peru and 107 in the USA. Principal Component analysis (PCA) with Varimax rotation was used to identify coherent trigger domains across and within samples. Resulting subscales were evaluated for internal consistency.Results: PCA suggested differences in factor structures between sites. Whereas the USA sample largely replicated original factors for animal allergens, pollen allergens, physical activity, air pollution/irritants, infections, and psychology, the initial analysis of the Peru sample suggested substantial overlap of air pollution/irritant, infection, and allergen items. Subsequent analysis of an expanded research form of the ATI for the Peru site culminated in extraction of five factors related to psychology, climate/temperature, combined pollen and animal allergens, physical activity, and infection. Internal consistencies were in an acceptable to excellent range (α = 0.74 to 0.94). Additional free trigger responses confirmed the importance of climate variables for patients in Peru. Psychological triggers were reported by 26% (Peru) and 31% (USA) of patients.Conclusion: Coherent trigger domains are readily identified and measured reliably by a Spanish-language ATI version. However, factor structures vary between samples from different Hispanic/Latino cultural and geographic domains. Culturally adapted versions of this instrument are therefore required for Hispanic/Latino population studies.
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Asma/epidemiologia , Asma/fisiopatologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Poluição do Ar/efeitos adversos , Alérgenos/efeitos adversos , Competência Cultural , Exercício Físico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Peru/epidemiologia , Análise de Componente Principal , Psicometria , Reprodutibilidade dos Testes , Fatores Socioeconômicos , Inquéritos e Questionários , Tradução , Estados Unidos/epidemiologia , Adulto JovemRESUMO
There is increased evidence demonstrating the association between Crohn's Disease (CD), a type of Inflammatory Bowel Disease (IBD), and non-diarrheagenic Adherent/Invasive Escherichia coli (AIEC) isolates. AIEC strains are phenotypically characterized by their adhesion, invasion and intra-macrophage survival capabilities. In the present study, the genomes of five AIEC strains isolated from individuals without IBD (four from healthy donors and one from peritoneal liquid) were sequenced and compared with AIEC prototype strains (LF82 and NRG857c), and with extra-intestinal uropathogenic strain (UPEC CFT073). Non-IBD-AIEC strains showed an Average Nucleotide Identity up to 98% compared with control strains. Blast identities of the five non-IBD-AIEC strains were higher when compared to AIEC and UPEC reference strains than with another E. coli pathotypes, suggesting a relationship between them. The SNPs phylogeny grouped the five non-IBD-AIEC strains in one separated cluster, which indicates the emergence of these strains apart from the AIEC group. Additionally, four genomic islands not previously reported in AIEC strains were identified. An incomplete Type VI secretion system was found in non-IBD-AIEC strains; however, the Type II secretion system was complete. Several groups of genes reported in AIEC strains were searched in the five non-IBD-AIEC strains, and the presence of fimA, fliC, fuhD, chuA, irp2 and cvaC were confirmed. Other virulence factors were detected in non-IBD-AIEC strains, which were absent in AIEC reference strains, including EhaG, non-fimbrial adhesin 1, PapG, F17D-G, YehA/D, FeuC, IucD, CbtA, VgrG-1, Cnf1 and HlyE. Based on the differences in virulence determinants and SNPs, it is plausible to suggest that non-IBD AIEC strains belong to a different pathotype.
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Escherichia coli/genética , Genoma Bacteriano , Filogenia , Aderência Bacteriana , Farmacorresistência Bacteriana , Escherichia coli/classificação , Escherichia coli/patogenicidade , Fezes/microbiologia , Ilhas Genômicas , Voluntários Saudáveis , Humanos , Polimorfismo de Nucleotídeo Único , Fatores de Virulência/genéticaRESUMO
Burkholderia pseudomallei and Burkholderia cepacia complex are poorly studied in Mexico. The genotypic analysis of 38 strains isolated from children with pneumonia were identified and showed that both Burkholderia groups were present in patients. From our results, it is plausible to suggest that new species are among the analyzed strains.