RESUMO
Investment in Africa over the past year with regards to SARS-CoV-2 genotyping has led to a massive increase in the number of sequences, exceeding 100,000 genomes generated to track the pandemic on the continent. Our results show an increase in the number of African countries able to sequence within their own borders, coupled with a decrease in sequencing turnaround time. Findings from this genomic surveillance underscores the heterogeneous nature of the pandemic but we observe repeated dissemination of SARS-CoV-2 variants within the continent. Sustained investment for genomic surveillance in Africa is needed as the virus continues to evolve, particularly in the low vaccination landscape. These investments are very crucial for preparedness and response for future pathogen outbreaks. One-Sentence SummaryExpanding Africa SARS-CoV-2 sequencing capacity in a fast evolving pandemic.
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The progression of the SARS-CoV-2 pandemic in Africa has so far been heterogeneous and the full impact is not yet well understood. Here, we describe the genomic epidemiology using a dataset of 8746 genomes from 33 African countries and two overseas territories. We show that the epidemics in most countries were initiated by importations, predominantly from Europe, which diminished following the early introduction of international travel restrictions. As the pandemic progressed, ongoing transmission in many countries and increasing mobility led to the emergence and spread within the continent of many variants of concern and interest, such as B.1.351, B.1.525, A.23.1 and C.1.1. Although distorted by low sampling numbers and blind-spots, the findings highlight that Africa must not be left behind in the global pandemic response, otherwise it could become a breeding ground for new variants.
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This work describes the study of the chemical composition and bioactivity of the essential oils (EOs) of the different organs (leaves, flowers, stems and roots) from Eruca vesicaria. According to the GC and GC/MS analysis, all the EOs were dominated by erucin (4-methylthiobutyl isothiocyanate) with a percentage ranging from 17.9 % (leaves) to 98.5 % (roots). The isolated EOs were evaluated for their antioxidant (DPPH, ABTS and ß-carotene/linoleic acid), antibacterial and inhibitory property against α-amylase and α-glucosidase. Most EOs exhibited an interesting α-glucosidase and α-amylase inhibitory potential. The roots essential oil was found to be the most active with IC50 values of 0.80±0.06 and 0.11±0.01â µg mL-1 , respectively. The essential oil of roots exhibited the highest antioxidant activity (DPPH, PI=92.76±0.01 %; ABTS, PI=78.87±0.19; and ß-carotene, PI=56.1±0.01 %). The isolated oils were also tested for their antibacterial activity against two Gram-positive and three Gram-negative bacteria. Moderate results have been noted by comparison with Gentamicin used as positive control.
Assuntos
Antioxidantes/química , Brassicaceae/metabolismo , Óleos Voláteis/química , Antibacterianos/química , Antibacterianos/farmacologia , Brassicaceae/química , Flores/química , Flores/metabolismo , Cromatografia Gasosa-Espectrometria de Massas , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Hipoglicemiantes/química , Óleos Voláteis/metabolismo , Óleos Voláteis/farmacologia , Folhas de Planta/química , Folhas de Planta/metabolismo , Raízes de Plantas/química , Raízes de Plantas/metabolismo , alfa-Glucosidases/química , alfa-Glucosidases/metabolismoRESUMO
Objective To examine the potential antimicrobial activity of Euphorbia paralias L. (Euphorbiaeae) leaves and stems extracts. Methods The antimicrobial activity was tested against six microbial strains: Escherichia coli ATCC 8739, Bacillus subtilis ATCC 6633, Salmonella enterica CIP 8039, Staphylococcus aureus ATCC 6538, Pseudomonas aeruginosa ATCC 9027 and Candida albicans ATCC 90028 by two different methods, the disk method and the dilution method. Results Our results showed the important antimicrobial activity of the chloroform extract of the stems towards the majority of the strains by using both methods. Bacillus subtilis was the most sensitive strain (MIC = MBC = 15 μg/mL). Conclusion Thus, some extracts of Euphorbia paralias can be used in the treatment of infectious diseases caused by microbes.
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Ecthyma gangrenosum is a characteristic lesion of Pseudomonas aeruginosa sepsis in immunocompromised patients. Only eight cases of ecthyma gangrenosum caused by Escherichia coli have been reported. We report a case of ecthyma gangrenosum due to E. coli without bacteremia in a previously healthy girl.
Assuntos
Ectima/microbiologia , Infecções por Escherichia coli/microbiologia , Antibacterianos/uso terapêutico , Cefotaxima/uso terapêutico , Criança , Ectima/diagnóstico , Ectima/tratamento farmacológico , Escherichia coli/isolamento & purificação , Infecções por Escherichia coli/diagnóstico , Infecções por Escherichia coli/tratamento farmacológico , Feminino , Humanos , Necrose , PrognósticoRESUMO
The aim of this study was to investigate the antibacterial and the cytotoxic activity of the acetone extract of the flowers of Salvia sclarea and of some natural products (sclareol, sclareolide and ambrox). The antibacterial and the cytotoxic activity were determined by the dilution method. Sclareolide, ambrox and sclareol demonstrated a good antibacterial activity against Staphylococcus aureus ATCC 25923, Pseudomonas aeruginosa ATCC 27950, Escherichia coli ATCC 25922 and Enterococcus faecalis ATCC 29212. The acetonic extract of the flowers of Salvia sclarea has a significant cytotoxic activity against Hep-2 cells.
Assuntos
Acetona/química , Antibacterianos/farmacologia , Antineoplásicos/farmacologia , Diterpenos/farmacologia , Furanos/farmacologia , Naftalenos/farmacologia , Salvia , Solventes/química , Antibacterianos/química , Antineoplásicos/química , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Enterococcus faecalis/efeitos dos fármacos , Enterococcus faecalis/crescimento & desenvolvimento , Escherichia coli/efeitos dos fármacos , Escherichia coli/crescimento & desenvolvimento , Flores , Humanos , Concentração Inibidora 50 , Neoplasias Hepáticas/patologia , Testes de Sensibilidade Microbiana , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Pseudomonas aeruginosa/efeitos dos fármacos , Pseudomonas aeruginosa/crescimento & desenvolvimento , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/crescimento & desenvolvimentoRESUMO
Antibacterial and antifungal activities of extracts obtained from M. alysson, R. raetam were tested using a solid medium technique. We showed that the petroleum ether extract of M. alysson had a Minimum Inhibitory Concentration (MIC) varied from 128 to 2000 microg mL(-1) against different Enterobacteriaceae and antifungal activity against Candida glabrata, Candida albicans, Candida parapsilosis and Candida kreusei with a MIC of 256 microg mL(-1). The ethyl acetate extract of R. raetam showed the best activity against Gram positive organisms with MICs of 128 to 256 microg mL(-1) against methicillin resistant Staphylococcus aureus but low activity against the different Candida species.