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1.
Antibiotics (Basel) ; 11(9)2022 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-36139927

RESUMO

Salmonella continues to be a major threat to public health, especially with respect to strains from a poultry origin. In recent years, an increasing trend of antimicrobial resistance (AMR) in Salmonella spp. was observed due to the misuse of antibiotics. Among the approaches advised for overcoming AMR, probiotics from the Lactobacillus genus have increasingly been considered for use as effective prophylactic and therapeutic agents belonging to the indigenous microbiota. In this study, we isolated lactobacilli from the ilea and ceca of hens and broilers in order to evaluate their potential probiotic properties. Four species were identified as Limosilactobacillusreuteri (n = 22, 45.8%), Ligilactobacillussalivarius (n = 20, 41.6%), Limosilactobacillus fermentum (n = 2, 4.2%) and Lactobacillus crispatus (n = 1, 2%), while three other isolates (n = 3, 6.25%) were non-typable. Eight isolates, including Ligilactobacillussalivarius (n = 4), Limosilactobacillusreuteri (n = 2), L. crispatus (n = 1) and Lactobacillus spp. (n = 1) were chosen on the basis of their cell surface hydrophobicity and auto/co-aggregation ability for further adhesion assays using the adenocarcinoma cell line Caco-2. The adhesion rate of these strains varied from 0.53 to 10.78%. Ligilactobacillussalivarius A30/i26 and 16/c6 and Limosilactobacillus reuteri 1/c24 showed the highest adhesion capacity, and were assessed for their ability to compete in and exclude the adhesion of Salmonella to the Caco-2 cells. Interestingly, Ligilactobacillussalivarius 16/c6 was shown to significantly exclude the adhesion of the three Salmonella serotypes, S. Enteritidis, S. Infantis and S. Kentucky ST 198, to Caco-2 cells. The results of the liquid co-culture assays revealed a complete inhibition of the growth of Salmonella after 24 h. Consequently, the indigenous Ligilactobacillussalivarius 16/c6 strain shows promising potential for use as a preventive probiotic added directly to the diet for the control of the colonization of Salmonella spp. in poultry.

2.
Zoonoses Public Health ; 69(5): 499-513, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35301827

RESUMO

This cross-sectional study was conducted to determine the prevalence of Salmonella at different stages of the broiler production chain and layer flocks in addition to their antibiotic resistance profile and molecular patterns. Over a period of 3 years, different sample matrices were collected from Lebanese farms, slaughterhouses and retail markets. Out of 672 Salmonella serotyped, 514 were analysed for antimicrobial resistance and 214 for clonality using Pulsed-field gel electrophoresis (PFGE). The results highlighted an important prevalence of Salmonella, 30% in farms, 35.8% in slaughterhouses and 22.4% at retail level. A large diversity of serotypes was identified with predominance among Salmonella Infantis (32.9%), Salmonella Enteritidis (28.4%) and Salmonella Kentucky (21.4%). High resistance to nalidixic acid was revealed in all the isolates. The most prominent resistance was exhibited in S. Kentucky and S. Infantis. The latter was resistant to tetracycline (99%), streptomycin (88.2%) and remarkable multi-drug resistance (MDR) (89.7%). All S. Kentucky isolates were resistant to ciprofloxacin, MDR (62.4%) and 6% were resistant to extended-spectrum cephalosporin (ESCs). One persistent clone of S. Enteritidis was found common between poultry and humans. Similar genomic profiles were detected between farms, slaughterhouses and retail suggesting the dissemination of identical clones throughout the food chain possibly due to weak barriers preventing such transmission.


Assuntos
Galinhas , Aves Domésticas , Animais , Antibacterianos/farmacologia , Estudos Transversais , Farmacorresistência Bacteriana Múltipla , Eletroforese em Gel de Campo Pulsado/veterinária , Fazendas , Testes de Sensibilidade Microbiana/veterinária , Salmonella , Salmonella enteritidis/genética
3.
Cells ; 10(11)2021 11 02.
Artigo em Inglês | MEDLINE | ID: mdl-34831207

RESUMO

Cancer stem cells (CSCs) are a distinct subpopulation of tumor cells with stem cell-like features. Able to initiate and sustain tumor growth and mostly resistant to anti-cancer therapies, they are thought responsible for tumor recurrence and metastasis. Recent accumulated evidence supports that iron metabolism with the recent discovery of ferroptosis constitutes a promising new lead in the field of anti-CSC therapeutic strategies. Indeed, iron uptake, efflux, storage and regulation pathways are all over-engaged in the tumor microenvironment suggesting that the reprogramming of iron metabolism is a crucial occurrence in tumor cell survival. In particular, recent studies have highlighted the importance of iron metabolism in the maintenance of CSCs. Furthermore, the high concentration of iron found in CSCs, as compared to non-CSCs, underlines their iron addiction. In line with this, if iron is an essential macronutrient that is nevertheless highly reactive, it represents their Achilles' heel by inducing ferroptosis cell death and therefore providing opportunities to target CSCs. In this review, we first summarize our current understanding of iron metabolism and its regulation in CSCs. Then, we provide an overview of the current knowledge of ferroptosis and discuss the role of autophagy in the (regulation of) ferroptotic pathways. Finally, we discuss the potential therapeutic strategies that could be used for inducing ferroptosis in CSCs to treat cancer.


Assuntos
Ferroptose , Ferro/metabolismo , Células-Tronco Neoplásicas/patologia , Animais , Autofagia , Humanos , Modelos Biológicos , Terapia de Alvo Molecular
4.
Int J Food Microbiol ; 353: 109295, 2021 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-34166957

RESUMO

Spices and herbs are widely used in almost all types of food preparation and their microbial contamination may cause spoilage and pose public health risk. Thus, the aim of this study was to assess the effect of packaging, source and a food safety management system (FSMS) on the microbiological quality of spices and dried herbs in a developing country, like Lebanon. For this, a total of 96 composite samples of thirteen most commonly consumed types of spices and dried herbs were collected twice at three-month interval. Each type was purchased in 5 common brands from 4 categories: packaged in companies with FSMS, packaged in companies without FSMS, packaged imported, and unpackaged. Total aerobic mesophilic bacteria (TAMB), sulfite reducing anaerobic bacteria, C. perfringens, coliforms, E. coli, yeasts and molds were found in 89%, 43%, 18%, 15%, 1% and 54% of the samples, respectively. All samples were negative for Salmonella. One per cent, 4%, 6%, 1% and 7% of the samples had unacceptable levels of TAMB, coliforms, sulfite reducing anaerobic bacteria, E. coli, yeasts and molds, respectively. Among the four categories, imported samples had the lowest microbiological load, followed by locally packaged in companies with FSMS, then locally packaged in companies without FSMS and the highest microbiological load was for the unpackaged spices and dried herbs. This study highlighted the importance of storage conditions, good hygienic practices, process controls and FSMSs in the spices and dried herbs sector.


Assuntos
Microbiologia de Alimentos , Embalagem de Alimentos , Gestão da Segurança , Especiarias , Fenômenos Fisiológicos Bacterianos , Países em Desenvolvimento , Microbiologia de Alimentos/instrumentação , Microbiologia de Alimentos/métodos , Embalagem de Alimentos/normas , Fungos/fisiologia , Gestão da Segurança/métodos , Especiarias/microbiologia
5.
J Glob Antimicrob Resist ; 23: 408-416, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33212287

RESUMO

OBJECTIVES: Salmonella enterica subsp. enterica serovar Kentucky has been associated with the worldwide ciprofloxacin-resistant (CIPR) Salmonella Kentucky sequence type 198 (ST198) epidemic clone, mostly recovered from poultry farms and products. The aim of this study was to examine whether this expanding clone exists in the Lebanese broiler chain. METHODS: Eight CIPR and extended-spectrum cephalosporin-resistant Salmonella Kentucky isolates previously recovered from Lebanese broilers were genetically characterised by whole-genome sequencing. RESULTS: Seven of the eight isolates belonged to ST198 and were phylogenetically closely related. They all harboured mutations in the chromosomal quinolone resistance genesgyrA and parC with double and single substitutions, respectively. The blaTEM-1B and blaCMY-2 genes were both detected in six isolates. Insertion sequence ISEcp1 was located upstream of blaCMY-2, harboured by IncI1 plasmids in four strains. An IS10 transposition coupled to homologous recombination at transposition sites mediated CMY-2 plasmid integration into the chromosome of one strain. Resistance genes to aminoglycosides [aadA7 and aac(3)-Id], tetracyclines [tet(A)] and sulfonamides (sul1) were detected in five strains, among which four were positive for the presence of Salmonella genomic island 1 (SGI1) variant SGI1-K. All studied isolates harboured a variety of Salmonella pathogenicity islands (SPIs) as well as common regulatory and virulence genes. CONCLUSION: Here we report for the first time in Lebanon the detection and dissemination of the emerging highly drug-resistantSalmonella Kentucky ST198. Our findings shed new light on this clone as a potential public-health threat.


Assuntos
Farmacorresistência Bacteriana Múltipla , Salmonella enterica , Animais , Galinhas , Farmacorresistência Bacteriana Múltipla/genética , Kentucky , Líbano , Testes de Sensibilidade Microbiana , Salmonella , Salmonella enterica/genética , beta-Lactamases
6.
Parasit Vectors ; 11(1): 389, 2018 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-29973261

RESUMO

BACKGROUND: Blastocystis sp. is a common protozoan parasite frequently identified in the digestive tract of humans and a large variety of animal hosts worldwide, including birds. It exhibits a large genetic diversity with the identification of 17 subtypes (STs), most of them with low host specificity. ST6 and ST7 were identified in birds and suggested to represent avian STs only in the context of scarce small-scale epidemiological surveys. Moreover, these two STs also account for a significant proportion of human infections whose zoonotic origin has never been clearly confirmed. Therefore, molecular screening of Blastocystis sp. was conducted by quantitative real-time PCR for fecal samples from poultry farms and their in-contact humans from slaughterhouses in Lebanon. In parallel, a control group consisting of patients hospitalized in the same geographical area and reporting no contact with poultry was also screened for the presence of the parasite. RESULTS: The overall prevalence of Blastocystis sp. was shown to reach around 32% in chicken samples and 65% in the farms screened. All the avian isolates were subtyped and belonged to either ST6 or ST7, with a large predominance of ST6. Fifty-four percent of slaughterhouse staff members were positive for Blastocystis sp. compared with a similar prevalence of 56% in hospitalized patients. ST3 was predominant in both human cohorts followed by either ST1 then ST2 among slaughterhouse staff or by ST2 then ST1 among hospitalized patients. ST6 was also identified in two slaughterhouse workers and not in the group of hospitalized patients. Gene sequence identity was observed between chicken and human ST6 isolates from the same slaughterhouse. CONCLUSIONS: Our data revealed a high prevalence of Blastocystis sp. in chicken samples and confirmed that ST6 and ST7 represented avian-adapted STs. Among both human cohorts, Blastocystis sp. infection was shown to exceed 50% with a predominance of ST3. The identification of ST6 in slaughterhouse staff members confirmed the zoonotic transmission of this ST through repeated and direct contact between chickens and their handlers.


Assuntos
Infecções por Blastocystis/veterinária , Blastocystis/genética , Blastocystis/isolamento & purificação , Doenças das Aves Domésticas/epidemiologia , Zoonoses/epidemiologia , Matadouros , Adulto , Animais , Blastocystis/classificação , Infecções por Blastocystis/epidemiologia , Infecções por Blastocystis/parasitologia , Infecções por Blastocystis/transmissão , Galinhas , DNA de Protozoário/genética , DNA Ribossômico/genética , Fezes/parasitologia , Feminino , Variação Genética , Humanos , Líbano/epidemiologia , Masculino , Pessoa de Meia-Idade , Aves Domésticas , Doenças das Aves Domésticas/parasitologia , Doenças das Aves Domésticas/transmissão , Prevalência , Reação em Cadeia da Polimerase em Tempo Real , Adulto Jovem , Zoonoses/parasitologia , Zoonoses/transmissão
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