RESUMO

Mastitis caused by Staphylococcus aureus is a worldwide problem in dairy farms, in part because of the pathogenicity of the bacteria, biofilm formation, and mechanisms of antimicrobial resistance that make the disease difficult to diagnose and treat, which is typically done with the use of beta-lactam antibiotics. The aim of the present study was to determine the virulence and resistance factors of S. aureus isolates from subclinical mastitis, blaZ + /mecA - /mecC - , resistant and sensitive to oxacillin. All isolates were classified as CC97 by MLST analysis, a clonal complex well adapted to the mammary gland and although STAU23 and STAU73 were resistant to oxacillin while STAU32 and STAU78 were sensitive, the genomic analysis identified only the blaZ operon corresponding to resistance to beta-lactams. However, the presence of the sdrC gene was revealed exclusively in resistant isolates, an important adhesin in the colonization process that potentiates pathogenicity in S. aureus. In addition, resistance islands (REIs) were identified in these isolates, suggesting more conserved REIs. In the analysis of SNPs throughout the genome, mutations were found in the trmB and smpB genes of the resistant isolates and in the murD and rimM genes of the sensitive isolates. This study highlights the potential benefit of genome-wide characterization tools to identify molecular mechanisms of S. aureus in bovine mastitis.

Assuntos

RESUMO

Aeromonas veronii is a Gram-negative bacterial species that causes disease in fish and is nowadays increasingly recurrent in enteric infections of humans. This study was performed to characterize newly sequenced isolates by comparing them with complete genomes deposited at the NCBI (National Center for Biotechnology Information). Nine isolates from fish, environments, and humans from the São Francisco Valley (Petrolina, Pernambuco, Brazil) were sequenced and compared with complete genomes available in public databases to gain insight into taxonomic assignment and to better understand virulence and resistance profiles of this species within the One Health context. One local genome and four NCBI genomes were misidentified as A. veronii. A total of 239 virulence genes were identified in the local genomes, with most encoding adhesion, motility, and secretion systems. In total, 60 genes involved with resistance to 22 classes of antibiotics were identified in the genomes, including mcr-7 and cphA. The results suggest that the use of methods such as ANI is essential to avoid misclassification of the genomes. The virulence content of A. veronii from local isolates is similar to those complete genomes deposited at the NCBI. Genes encoding colistin resistance are widespread in the species, requiring greater attention for surveillance systems.

RESUMO

BACKGROUND: This study aimed to describe the kinetics of Leishmania parasite load determined using kinetoplast DNA (kDNA)-based quantitative polymerase chain reaction (qPCR) in visceral leishmaniasis (VL) patients. METHODS: Parasite load in blood was assessed by qPCR at five time points, up to 12 months post-diagnosis. Sixteen patients were followed up. RESULTS: A significant reduction in the parasite load was observed after treatment (P < 0.0001). One patient had an increased parasite load 3 months post-treatment and relapsed clinically at month six. CONCLUSIONS: We have described the use of kDNA-based qPCR in the post-treatment follow-up of VL cases.

Assuntos

RESUMO

Pisciculture represents one of the industries with the fastest growth rates worldwide. However, it presents obstacles to its development, such as bacteriosis, which is conventionally treated with antibiotics. The indiscriminate and inappropriate use of antibiotics can lead to bacterial resistance, thus alternatives to the use of antibiotics have been researched. The study aimed to analyze the potential of crude ethanol extract (CEE) from Hymenaea martiana leaf, gallic acid (GA), and polypyrrole (PPy) against Aeromonas hydrophila. Tests were performed to determine the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of the compounds individually and in synergy (checkerboard) against A. hydrophila and in silico tests between the compounds evaluated. The CEE of H. martiana leaf and PPy were effective against A. hydrophila with MBC results of 3125 µg/mL for the CEE of H. martiana and 125 µg/mL for PPy. Evaluating the GA, a MIC and MBC of 125 µg/mL was obtained. In the interaction tests (checkerboard, using PPy/CEE and PPy/GA), there was a significant reduction in individual introductions. Thus, for the PPy/CEE tests, we had a reduction of MIC/MBC to 1.95 and 781.25 µg/mL, and for the synergy tests between PPy/GA to 7.8125 and 31.125 µg/mL, respectively. The synergy tests are encouraging, and it is possible to verify a decrease of up to 98% in the introduction of PPy, 75% in CEE for H. martiana and 75.1% for GA, when compared to their individual tests. The tests with GA are encouraging due to GA's effectiveness as an antimicrobial agent and high synergy with polypyrrole, both in vitro results and molecular docking experiments showed the actions at the same activation site in A. hydrophila. In vivo tests evaluating isolated components of CEE from H. martiana in synergy with PPy should be performed, to verify the quality of the interactions and the improvement of the immune responses of the animals. It was evidenced that gallic acid, a substance isolated from the extract, tends to have more promising results. This is relevant since the industry has been developing these compounds for different uses, thus providing easier access to the product. Thus, the present study indicates an efficient alternative in the use of bioactive compounds as substitutes for conventional antimicrobials.

Assuntos

RESUMO

ABSTRACT Background: This study aimed to describe the kinetics of Leishmania parasite load determined using kinetoplast DNA (kDNA)-based quantitative polymerase chain reaction (qPCR) in visceral leishmaniasis (VL) patients. Methods: Parasite load in blood was assessed by qPCR at five time points, up to 12 months post-diagnosis. Sixteen patients were followed up. Results: A significant reduction in the parasite load was observed after treatment (P < 0.0001). One patient had an increased parasite load 3 months post-treatment and relapsed clinically at month six. Conclusions: We have described the use of kDNA-based qPCR in the post-treatment follow-up of VL cases.

RESUMO

RESUMO Objetivo: Analisar e comparar as características de pacientes críticos com a COVID-19, a abordagem clínica e os resultados entre os períodos de pico e de platô na primeira onda pandêmica em Portugal. Métodos: Este foi um estudo de coorte multicêntrico ambispectivo, que incluiu pacientes consecutivos com a forma grave da COVID-19 entre março e agosto de 2020 de 16 unidades de terapia intensiva portuguesas. Definiram-se as semanas 10 - 16 e 17 - 34 como os períodos de pico e platô. Resultados: Incluíram-se 541 pacientes adultos com mediana de idade de 65 [57 - 74] anos, a maioria do sexo masculino (71,2%). Não houve diferenças significativas na mediana de idade (p = 0,3), no Simplified Acute Physiology Score II (40 versus 39; p = 0,8), na pressão parcial de oxigênio/fração inspirada de oxigênio (139 versus 136; p = 0,6), na terapia com antibióticos na admissão (57% versus 64%; p = 0,2) ou na mortalidade aos 28 dias (24,4% versus 22,8%; p = 0,7) entre o período de pico e platô. Durante o período de pico, os pacientes tiveram menos comorbidades (1 [0 - 3] versus 2 [0 - 5]; p = 0,002); fizeram mais uso de vasopressores (47% versus 36%; p < 0,001) e ventilação mecânica invasiva na admissão (58,1% versus 49,2%; p < 0,001), e tiveram mais prescrição de hidroxicloroquina (59% versus 10%; p < 0,001), lopinavir/ritonavir (41% versus 10%; p < 0,001) e posição prona (45% versus 36%; p = 0,04). Entretanto, durante o platô, observou-se maior uso de cânulas nasais de alto fluxo (5% versus 16%; p < 0,001) na admissão, remdesivir (0,3% versus 15%; p < 0,001) e corticosteroides (29% versus 52%; p < 0,001), além de menor tempo de internação na unidade de terapia intensiva (12 versus 8 dias; p < 0,001). Conclusão: Houve mudanças significativas nas comorbidades dos pacientes, nos tratamentos da unidade de terapia intensiva e no tempo de internação entre os períodos de pico e platô na primeira onda da COVID-19.

ABSTRACT Objective: To analyze and compare COVID-19 patient characteristics, clinical management and outcomes between the peak and plateau periods of the first pandemic wave in Portugal. Methods: This was a multicentric ambispective cohort study including consecutive severe COVID-19 patients between March and August 2020 from 16 Portuguese intensive care units. The peak and plateau periods, respectively, weeks 10 - 16 and 17 - 34, were defined. Results: Five hundred forty-one adult patients with a median age of 65 [57 - 74] years, mostly male (71.2%), were included. There were no significant differences in median age (p = 0.3), Simplified Acute Physiology Score II (40 versus 39; p = 0.8), partial arterial oxygen pressure/fraction of inspired oxygen ratio (139 versus 136; p = 0.6), antibiotic therapy (57% versus 64%; p = 0.2) at admission, or 28-day mortality (24.4% versus 22.8%; p = 0.7) between the peak and plateau periods. During the peak period, patients had fewer comorbidities (1 [0 - 3] versus 2 [0 - 5]; p = 0.002) and presented a higher use of vasopressors (47% versus 36%; p < 0.001) and invasive mechanical ventilation (58.1 versus 49.2%; p < 0.001) at admission, prone positioning (45% versus 36%; p = 0.04), and hydroxychloroquine (59% versus 10%; p < 0.001) and lopinavir/ritonavir (41% versus 10%; p < 0.001) prescriptions. However, a greater use of high-flow nasal cannulas (5% versus 16%, p < 0.001) on admission, remdesivir (0.3% versus 15%; p < 0.001) and corticosteroid (29% versus 52%, p < 0.001) therapy, and a shorter ICU length of stay (12 days versus 8, p < 0.001) were observed during the plateau. Conclusion: There were significant changes in patient comorbidities, intensive care unit therapies and length of stay between the peak and plateau periods of the first COVID-19 wave.

RESUMO

Femoral head separation (FHS) is characterized by the detachment of growth plate (GP) and articular cartilage, occurring in tibia and femur. However, the molecular mechanisms involved with this condition are not completely understood. Therefore, genes and biological processes (BP) involved with FHS were identified in 21-day-old broilers through RNA sequencing of the femoral GP. 13,487 genes were expressed in the chicken femoral head transcriptome of normal and FHS-affected broilers. From those, 34 were differentially expressed (DE; FDR ≤0.05) between groups, where all of them were downregulated in FHS-affected broilers. The main BP were enriched in receptor signaling pathways, ossification, bone mineralization and formation, skeletal morphogenesis, and vascularization. RNA-Seq datasets comparison of normal and FHS-affected broilers with 21, 35 and 42 days of age has shown three shared DE genes (FBN2, C1QTNF8, and XYLT1) in GP among ages. Twelve genes were exclusively DE at 21 days, where 10 have already been characterized (SHISA3, FNDC1, ANGPTL7, LEPR, ENSGALG00000049529, OXTR, ENSGALG00000045154, COL16A1, RASD2, BOC, GDF10, and THSD7B). Twelve SNPs were associated with FHS (p < 0.0001). Out of those, 5 were novel and 7 were existing variants located in 7 genes (RARS, TFPI2, TTI1, MAP4K3, LINK54, and AREL1). We have shown that genes related to chondrogenesis and bone differentiation were downregulated in the GP of FHS-affected young broilers. Therefore, these findings evince that candidate genes pointed out in our study are probably related to the onset of FHS in broilers.

RESUMO

Femoral head separation (FHS) is usually a subclinical condition characterized by the detachment of articular cartilage from the bone. In this study, a comprehensive analysis identifying shared and exclusive expression profiles, biological processes (BP) and variants related to FHS in the femoral articular cartilage and growth plate in chickens was performed through RNA sequencing analysis. Thirty-six differentially expressed (DE) genes were shared between femoral articular cartilage (AC) and growth plate (GP) tissues. Out of those, 23 genes were enriched in BP related to ion transport, translation factors and immune response. Seventy genes were DE exclusively in the AC and 288 in the GP. Among the BP of AC, the response against bacteria can be highlighted, and for the GP tissue, the processes related to chondrocyte differentiation and cartilage development stand out. When the chicken DE genes were compared to other datasets, eight genes (SLC4A1, RHAG, ANK1, MKNK2, SPTB, ADA, C7 and EPB420) were shared between chickens and humans. Furthermore, 89 variants, including missense in the SPATS2L, PRKAB1 and TRIM25 genes, were identified between groups. Therefore, those genes should be more explored to validate them as candidates to FHS/FHN in chickens and humans.

RESUMO

There is not a consensus between the presence of the genotypic resistance marker gene and the phenotypic resistance to ß-lactams in Staphylococcus aureus, which means, positive S. aureus blaZ isolates demonstrating sensitivity to ß-lactams. The present study aimed to characterize the blaZ, blaR1 and blaI genes, identify and evaluate single nucleotide polymorphisms (SNPs) and their relationship with ß-lactam resistance in samples of Staphylococcus aureus obtained from cases of bovine mastitis. Five isolates (two resistant and three sensitive to oxacillin) of Staphylococcus aureus with detected production of beta-lactamase, previously evaluated as containing the blaZ gene and negative for the mecA and mecC genes, had the bla operon completely sequenced. Impacts on the protein sequence due to the detected polymorphisms were evaluated by modeling the proteins encoded by the blaZ, blaR1 and blaI genes using a three-dimensional model structure obtained from the Protein Data Bank (PDB) database. Fifteen SNPs were detected in the blaZ gene, 30 in the blaR1 gene and three in the blaI gene. These SNPs caused alterations in amino acid sites. Deleterious mutations were detected in the blaZ gene (E146G, P218S, Y221C) and the blaR1 gene (K481E). Molecular docking analysis revealed that polymorphisms in the blaZ gene may explain the phenotypic sensitivity in isolates that contain the resistance marker gene. Although sensitive and resistant isolates encode beta-lactamase, these proteins are functionally altered due to a change in the binding site with the antibiotic.

Assuntos

RESUMO

INTRODUCTION: The Sociedade Portuguesa de Cuidados Intensivos and the Infection and Sepsis Group have previously issued health service and management recommendations for critically ill patients with COVID-19. Due to the evolution of knowledge, the panel of experts was again convened to review the current evidence and issue updated recommendations. METHODS: A national panel of experts who declared that they had no conflicts of interest regarding the development of the recommendations was assembled. Operational questions were developed based on the PICO methodology, and a rapid systematic review was conducted by consulting different bibliographic sources. The panel determined the direction and strength of the recommendations using two Delphi rounds, conducted in accordance with the principles of the GRADE system. A strong recommendation received the wording "is recommended", and a weak recommendation was written as "is suggested." RESULTS: A total of 48 recommendations and 30 suggestions were issued, covering the following topics: diagnosis of SARS-CoV-2 infection, coinfection and superinfection; criteria for admission, cure and suspension of isolation; organization of services; personal protective equipment; and respiratory support and other specific therapies (antivirals, immunomodulators and anticoagulation). CONCLUSION: These recommendations, specifically oriented to the Portuguese reality but that may also apply to Portuguese-speaking African countries and East Timor, aim to support health professionals in the management of critically ill patients with COVID-19. They will be continuously reviewed to reflect the progress of our understanding and the treatment of this pathology.

INTRODUÇÃO: A Sociedade Portuguesa de Cuidados Intensivos e o Grupo de Infeção e Sépsis emitiram previamente recomendações visando à organização dos serviços de saúde e ao manejo dos doentes críticos com COVID-19. Em virtude da evolução do conhecimento, o painel de peritos voltou a se organizar para rever a atual evidência e emitir recomendações atualizadas. MÉTODOS: Foi reunido um painel nacional de peritos que declararam não ter conflitos de interesse para o desenvolvimento das recomendações. Foram desenvolvidas perguntas operacionais conforme a metodologia PICO, e foi conduzida uma revisão sistemática rápida por meio da consulta de diferentes fontes bibliográficas. O painel determinou a direção e a força das recomendações com a utilização de duas rodadas de um método Delphi, conduzido seguindo princípios do sistema GRADE. Uma recomendação forte recebeu a redação "recomenda-se", e uma recomendação fraca foi redigida como "sugere-se". RESULTADOS: Foram emitidas 48 recomendações e 30 sugestões abrangendo os seguintes tópicos: diagnóstico de infecção por SARS-CoV-2, coinfecção e superinfecção; critérios de admissão, cura e suspensão de isolamento; organização dos serviços; Equipamentos de Proteção Individual; terapêuticas de suporte respiratório e outras e terapêuticas específicas (antivirais, imunomodeladores e anticoagulação). CONCLUSÃO: Essas recomendações, especificamente orientadas para a realidade portuguesa, mas que podem se aplicar também aos Países Africanos de Língua Oficial Portuguesa e ao Timor-Leste, visam apoiar os profissionais de saúde no manejo de doentes críticos com COVID-19. Pretende-se que sejam constantemente revistas, de modo a refletir o avanço de nossa compreensão e o da terapêutica dessa patologia.

Assuntos