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1.
Mymensingh Med J ; 30(2): 329-336, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33830110

RESUMO

The occurrence of antimicrobial resistance in Salmonella enterica serovars (both typhoidal and non-typhoidal Salmonellae) is a major public health problem especially in developing countries, which have been associated with treatment failures. Therefore, the study was undertaken to determine the current antimicrobial resistance pattern and extended spectrum ß-lactamase (ESBL) production among clinical isolates of Salmonella spp. during 2019-2020 in Mymensingh, Bangladesh. In this cross sectional study, 36 Salmonella enterica isolates were obtained from blood and stool culture of suspected 200 enteric fever and 100 gastroenteritis patients attending at Mymensingh Medical College Hospital, Mymensingh, Bangladesh. Isolated Salmonella species were identified by biochemical tests and Polymerase Chain Reaction (PCR). Disk diffusion test was performed by modified Kirby Bauer method. Minimum Inhibitory Concentration (MIC) of ceftriaxone was detected by agar dilution method. Double disk synergy test was used as a screening test for ESBL production. PCR was done for detection of blaTEM, blaSHV and blaCTX-MU genes. The isolates showed 25% resistance to Ceftriaxone and 58.3% to Azithromycin. The highest sensitivity rates were 88.9% to Meropenem and 83.3% to Amikacin. Whereas 6(16.7%) isolates were Multi Drug Resistant (MDR). Eight (8) isolates were confirmed as ESBL producer by DDST. The marked increase in MIC was observed between 8->512µg/ml to ceftriaxone. blaTEM, blaSHV and blaCTX-MU genes were detected in 3, 5 and 8 isolates respectively. In conclusion, the current study observed, higher level of resistance to ceftriaxone and azithromycin. At the same times 22.2% isolates showed ESBL production, which is a cause for concern as it may lead to treatment failure. On the other hand the study also showed the re-emergence of chloramphenicol and Sulfamethoxazole-Trimethoprim sensitivity.


Assuntos
Antibacterianos , beta-Lactamases , Antibacterianos/farmacologia , Bangladesh , Estudos Transversais , Farmacorresistência Bacteriana/genética , Humanos , Testes de Sensibilidade Microbiana , Salmonella/genética , beta-Lactamases/genética
2.
BMC Infect Dis ; 21(1): 181, 2021 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-33593278

RESUMO

BACKGROUND: Numerous multiplex-PCR assays are now available in routine diagnostics but their clinical value is controversial if a clear association between clinical symptoms and the detection of a particular pathogen is missing. The objective of this work was to evaluate a multiplex-PCR assay for the diagnosis of traveller's diarrhoea (TD) in a case-control study and to assess the concordance with the BioFire® FilmArray® Gastrointestinal Panel. METHODS: Stool samples from cases (n = 61) and controls (n = 30) were collected during travel and analysed by the GI-EB Screening assay (Seegene) in a case-control study. The concordance with the BioFire® FilmArray® Gastrointestinal Panel was expressed as the proportion of participants in which both tests agreed in the category "detected" and "not detected". RESULTS: None of the test-target organisms (Campylobacter spp., Clostridioides difficile toxin A/B, Salmonella spp., Shigella spp./enteroinvasive Escherichia coli, E. coli O157, Shiga toxin-producing E. coli, Yersinia enterocolitica) was significantly associated with TD GI-EB Screening assay. The GI-EB Screening assay had an agreement with the BioFire® FilmArray® of 86.8-100%. CONCLUSION: The selection of test-target organisms included in the GI-EB Screening assay appears inappropriate for the diagnostic work-up of TD as none of the detected pathogens was associated with TD. The GI-EB Screening assay had a good concordance with BioFire® FilmArray®.


Assuntos
Diarreia/diagnóstico , Fezes/microbiologia , Reação em Cadeia da Polimerase Multiplex/métodos , Adulto , Idoso , Estudos de Casos e Controles , DNA Bacteriano/genética , DNA Bacteriano/metabolismo , Diarreia/microbiologia , Escherichia coli/genética , Escherichia coli/isolamento & purificação , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Técnicas de Diagnóstico Molecular/métodos , Kit de Reagentes para Diagnóstico , Salmonella/genética , Salmonella/isolamento & purificação , Shigella/genética , Shigella/isolamento & purificação , Viagem
3.
Int J Food Microbiol ; 342: 109044, 2021 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-33529874

RESUMO

Antimicrobial resistance (AMR) in non-typhoidal Salmonella from poultry is a public health concern. Injudicious use of antibiotics in humans and agriculture fuels the emergence of resistance. The objective of this study was to characterize the prevalence, antibiotic susceptibility profiles and genetic resistance mechanisms of Salmonella isolated from US retail poultry meat samples with and without antibiotic-related claims. We reviewed data from 46,937 poultry meat samples collected from 2008 to 2017 through the FDA NARMS retail meat program. Antibiotic usage claims on the poultry packaging were used to categorize the sample as 'conventionally raised' or 'reduced or no antibiotic use'. The results show that the prevalence of Salmonella in conventional poultry samples (8.6%) was higher than reduced or no antibiotic use poultry samples (5.1%). The odds of resistance to three or more antimicrobial classes (multi-drug resistant) were 2.61 times higher for Salmonella isolates from conventional samples, compared to isolates from reduced antibiotic use samples. The frequency of the aminoglycoside resistance gene, strB, and the beta-lactam resistant gene, blaCMY-2, were higher in isolates from conventional meat. This study suggests that conventionally raised poultry meat was more likely to be contaminated with multi-drug resistant Salmonella, and those Salmonella are more likely to carry genes for antibiotics resistance.


Assuntos
Agricultura/métodos , Antibacterianos/uso terapêutico , Farmacorresistência Bacteriana , Aves Domésticas/microbiologia , Salmonella/efeitos dos fármacos , Animais , Antibacterianos/farmacologia , Farmacorresistência Bacteriana/efeitos dos fármacos , Farmacorresistência Bacteriana/genética , Genes Bacterianos , Testes de Sensibilidade Microbiana , Salmonella/genética , Salmonella/isolamento & purificação , Salmonelose Animal/tratamento farmacológico , Salmonelose Animal/microbiologia , Estados Unidos
4.
Nat Rev Microbiol ; 19(4): 222-223, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33564175
5.
Int J Food Microbiol ; 340: 109055, 2021 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-33485100

RESUMO

This study was undertaken to investigate the prevalence, serotype distribution and antimicrobial resistance in Salmonella isolated from retail meat in Southern China, and to characterize the major mechanisms that mediate the ciprofloxacin resistance of isolates. High levels of Salmonella contamination were detected in pork (67.0%), duck (50.5%) and chicken (46.2%). Thirty different serotypes were identified among 500 detected Salmonella isolates, as well as significant differences in serotypes between different retail meat samples. Notably, 405 (80.1%) isolates exhibited multidrug resistance (MDR). Meanwhile, we also found that 74 (14.8%) Salmonella isolates were resistant to ciprofloxacin and the major mechanisms underlying this resistance were investigated. The commonest mutations in gyrA S83F (40.5%) and D87N (35.1%), and in parC was T57S (71.6%) and S80I (35.1%). Multilocus sequence typing (MLST) and pulsed-field gel electrophoresis (PFGE) analysis revealed that the S. Kentucky isolates that were resistant to ciprofloxacin mostly belonged to ST198 (21/23, 91.3%) and PFGE revealed the presence of various genotypes. This study identified a diversity of Salmonella serotypes and a high prevalence of multidrug resistance (MDR) among Salmonella isolated from retail meat in Southern China, which indicates that foodborne Salmonella potentially constitutes a potential food safety risk.


Assuntos
Antibacterianos/farmacologia , Farmacorresistência Bacteriana Múltipla/genética , Carne/microbiologia , Mutação , Carne de Porco/microbiologia , Salmonella/genética , Animais , Galinhas , China , Ciprofloxacino/farmacologia , Patos , Eletroforese em Gel de Campo Pulsado , Microbiologia de Alimentos , Testes de Sensibilidade Microbiana , Tipagem de Sequências Multilocus , Salmonella/efeitos dos fármacos , Salmonella/isolamento & purificação , Sorogrupo , Suínos
6.
Appl Environ Microbiol ; 87(6)2021 02 26.
Artigo em Inglês | MEDLINE | ID: mdl-33397693

RESUMO

Freshwater can support the survival of the enteric pathogen Salmonella, though temporal Salmonella diversity in a large watershed has not been assessed. At 28 locations within the Susquehanna River basin, 10-liter samples were assessed in spring and summer over 2 years. Salmonella prevalence was 49%, and increased river discharge was the main driver of Salmonella presence. The amplicon-based sequencing tool, CRISPR-SeroSeq, was used to determine serovar population diversity and detected 25 different Salmonella serovars, including up to 10 serovars from a single water sample. On average, there were three serovars per sample, and 80% of Salmonella-positive samples contained more than one serovar. Serovars Give, Typhimurium, Thompson, and Infantis were identified throughout the watershed and over multiple collections. Seasonal differences were evident: serovar Give was abundant in the spring, whereas serovar Infantis was more frequently identified in the summer. Eight of the ten serovars most commonly associated with human illness were detected in this study. Crucially, six of these serovars often existed in the background, where they were masked by a more abundant serovar(s) in a sample. Serovars Enteritidis and Typhimurium, especially, were masked in 71 and 78% of samples where they were detected, respectively. Whole-genome sequencing-based phylogeny demonstrated that strains within the same serovar collected throughout the watershed were also very diverse. The Susquehanna River basin is the largest system where Salmonella prevalence and serovar diversity have been temporally and spatially investigated, and this study reveals an extraordinary level of inter- and intraserovar diversity.IMPORTANCE Salmonella is a leading cause of bacterial foodborne illness in the United States, and outbreaks linked to fresh produce are increasing. Understanding Salmonella ecology in freshwater is of importance, especially where irrigation practices or recreational use occur. As the third largest river in the United States east of the Mississippi, the Susquehanna River is the largest freshwater contributor to the Chesapeake Bay, and it is the largest river system where Salmonella diversity has been studied. Rainfall and subsequent high river discharge rates were the greatest indicators of Salmonella presence in the Susquehanna and its tributaries. Several Salmonella serovars were identified, including eight commonly associated with foodborne illness. Many clinically important serovars were present at a low frequency within individual samples and so could not be detected by conventional culture methods. The technologies employed here reveal an average of three serovars in a 10-liter sample of water and up to 10 serovars in a single sample.


Assuntos
Rios/microbiologia , Salmonella/isolamento & purificação , Genômica , Filogenia , Salmonella/genética , Estações do Ano , Sorogrupo , Microbiologia da Água , Sequenciamento Completo do Genoma
7.
J Food Prot ; 84(2): 321-332, 2021 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-33513257

RESUMO

ABSTRACT: Salmonella is a foodborne pathogen commonly associated with poultry products. The aims of this work were to (i) estimate the impact of critical steps of the slaughter process on Salmonella detection from broiler chicken carcasses in two commercial poultry slaughter plants in Quebec, Canada; (ii) investigate the presence of Salmonella in the slaughter plant environment; (iii) describe, using a high-resolution melting (HRM) approach, the HRM Salmonella profiles and serotypes present on carcasses and in the slaughter plant environment; and (iv) evaluate whether the HRM flock status after chilling could be predicted by the flock status at previous steps of the slaughter process, the status of previous flocks, or the status of the processing environment, for the same HRM profile. Eight visits were conducted in each slaughter plant over a 6-month period. In total, 379 carcass rinsates from 79 flocks were collected at five critical steps of the slaughter process. Environmental samples were also collected from seven critical sites in each slaughter plant. The bleeding step was the most contaminated, with >92% positive carcasses. A decrease of the contamination along the slaughtering process was noted, with carcasses sampled after dry-air chilling showing ≤2.5% Salmonella prevalence. The most frequently isolated serotypes were Salmonella Heidelberg, Kentucky, and Schwarzengrund. The detection of the Salmonella Heidelberg 1-1-1 HRM profile on carcasses after chilling was significantly associated with its detection at previous steps of the slaughter process and in previously slaughtered flocks from other farms during a same sampling day. Results highlight the importance of the chilling step in the control of Salmonella on broiler chicken carcasses and the need to further describe and compare the competitive advantage of Salmonella serotypes to survive processing. The current study also illustrates the usefulness of HRM typing in investigating Salmonella contamination along the slaughter process.


Assuntos
Matadouros , Galinhas , Animais , Canadá , Contaminação de Alimentos/análise , Microbiologia de Alimentos , Kentucky , Prevalência , Salmonella/genética
8.
Int J Food Microbiol ; 337: 108941, 2021 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-33181420

RESUMO

Whole genome sequencing (WGS) has made impressive progress in the field of molecular biology. Its most common application for public health is in the area of surveillance of food-borne diseases. WGS has the potential for providing a large amount of information, such as the identification of the strain type, the characterization of antibiotic resistance and virulence, and phylogeny. In our study, thirty-nine non-typhoidal Salmonella strains were isolated from diverse sources in Tunisia. Non-typhoidal Salmonella are among the most common pathogens contaminating food animals. The presence of virulence and antimicrobial resistance determinants in those strains were investigated using whole genome sequencing (WGS) and appropriate data analysis. The genomes were screened for several Salmonella virulence genes using the Virulence Factor Database VFDB. Twelve different virulence profiles, which correspond to the 12 identified serovars, were recognized. Several antimicrobial resistance genes were also detected: aac (6')-Iaa, sul1, tetA, bla-TEM and qnrS genes. Phylogenetic relationships among the strains were further assessed by a cgMLST analysis. The resulting phylogenetic tree consisted of several clusters consistently with the in silico multilocus sequence typing (MLST) and serotyping. Our findings demonstrated that WGS and subsequent data analysis provided an accurate tool for genetic characterization of bacterial strains compared to usual molecular typing techniques. To the best of our knowledge, this is the first report of an application of WGS for genetic characterization of food-borne Tunisian strains.


Assuntos
Genoma Bacteriano/genética , Filogenia , Salmonella , Virulência/genética , Animais , Farmacorresistência Bacteriana/genética , Tipagem de Sequências Multilocus/métodos , Salmonella/classificação , Salmonella/genética , Salmonella/patogenicidade , Sorogrupo , Sorotipagem , Tunísia , Sequenciamento Completo do Genoma
9.
Int J Food Microbiol ; 337: 108956, 2021 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-33189985

RESUMO

There has been an increase in the number of reports on Salmonella enterica subsp. enterica serovar Infantis (S. Infantis) isolated from animals and humans. Recent studies using whole genome sequencing (WGS) have provided evidence on the likely contribution of a unique conjugative megaplasmid (pESI; ~280 kb) to the dissemination of this serovar worldwide. In the present study, twenty-two unrelated Salmonella strains [S. Infantis (n = 20) and Salmonella 6,7:r:- (n = 2)] and their plasmids were investigated using next generation sequencing technologies (MiSeq and MinION) to unravel the significant expansion of this bacteria in Turkey. Multi-locus sequence typing, plasmid replicons, resistance gene contents as well as phylogenetic relations between strains were determined. According to the WGS data, all S. Infantis possessed the relevant megaplasmid backbone genes and belonged to sequence type 32 (ST32) with the exception of a single novel ST7091. Tetracycline and trimethoprim/sulfamethoxazole resistance were found to be widespread in S. Infantis strains and the resistant strains exclusively carried the tetA, sul1, sul2 and dfrA14 genes. One S. Infantis isolate was also a carrier of the plasmid-mediated ampC via blaCMY-2, gene. Moreover, full genomes of four S. Infantis isolates were reconstructed based on hybrid assembly. All four strains contained large plasmids (240-290 kb) similar to previously published megaplasmid (pESI) and accompanied by several small plasmids. The megaplasmid backbone contained a toxin-antitoxin system, two virulence cassettes and segments associated with heavy metals resistance, while variable regions possessed several antibiotic resistance genes flanked by mobile elements. This study indicated that pESI-like megaplasmid is widely disseminated within the tested S. Infantis strains of chicken meat, warranting further genomic studies on clinical strains from humans and animals to uncover the overall emergence and spread of this serovar.


Assuntos
Genoma Bacteriano/genética , Plasmídeos/genética , Aves Domésticas/microbiologia , Salmonelose Animal/microbiologia , Salmonella/genética , Animais , Antibacterianos/farmacologia , Galinhas/microbiologia , Farmacorresistência Bacteriana/efeitos dos fármacos , Farmacorresistência Bacteriana/genética , Microbiologia de Alimentos , Filogenia , Plasmídeos/efeitos dos fármacos , Salmonella/efeitos dos fármacos , Salmonella/isolamento & purificação , Salmonella/patogenicidade , Salmonelose Animal/epidemiologia , Turquia/epidemiologia , Virulência/genética
10.
Food Microbiol ; 93: 103601, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32912589

RESUMO

For decades, Salmonella Typhimurium and Salmonella Enteritidis have prevailed in several countries as agents of salmonellosis outbreaks. In Brazil, the largest exporter of poultry meat, relatively little attention has been paid to infrequent serovars. Here, we report the emergence and characterization of rare serovars isolated from food and related sources collected between 2014 and 2016 in Brazil. Twenty-two Salmonella enterica isolates were analyzed through the use of whole-genome sequencing (WGS) and clustered regularly interspaced short palindromic repeats (CRISPR) genotyping. These isolates were classified into 10 infrequent serovars, including S. Abony, S. Isangi, S. Rochdale, S. Saphra, S. Orion, S. Ouakam, S. Grumpensis, S. Carrau, S. Abaetetuba, and S. Idikan. The presence of six antimicrobial resistance (AMR) genes, qnrB19, blaCMY-2, tetA, aac(6')-Iaa, sul2 and fosA7, which encode resistance to quinolones, third-generation cephalosporin, tetracycline, aminoglycoside, sulfonamide and fosfomycin, respectively, were confirmed by WGS. All S. Isangi harbored qnrB19 with conserved genomic context across strains, while S. Abony harbored blaCMY-2. Twelve (54.5%) strains displayed chromosomal mutations in parC (Thr57→Ser). Most serovars were classified as independent lineages, except S. Abony and S. Abaetetuba, which phylogenetically nested with Salmonella strains from different countries. CRISPR analysis revealed that the spacer content was strongly correlated with serovar and multi-locus sequence type for all strains, independently confirming the observed phylogenetic patterns, and highlighting the value of CRISPR-based genotyping for Salmonella. These findings add valuable information to the epidemiology of S. enterica in Brazil, where the emergency of antibiotic-resistant Salmonella continues to evolve.


Assuntos
Antibacterianos/farmacologia , Farmacorresistência Bacteriana Múltipla/genética , Microbiologia de Alimentos , Genótipo , Salmonella enterica/genética , Salmonella enterica/isolamento & purificação , Sorogrupo , Brasil , Repetições Palindrômicas Curtas Agrupadas e Regularmente Espaçadas , Genoma Bacteriano , Técnicas de Genotipagem , Testes de Sensibilidade Microbiana , Salmonella/classificação , Salmonella/genética , Salmonella/isolamento & purificação , Intoxicação Alimentar por Salmonella , Salmonella enterica/classificação , Salmonella enterica/efeitos dos fármacos , Sorotipagem , Sequenciamento Completo do Genoma
11.
Methods Mol Biol ; 2182: 1-6, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-32894481

RESUMO

Molecular techniques such as real-time polymerase chain reaction (qPCR) have become a very effective alternative in food microbiology diagnostic for rapid and specific detection of foodborne pathogens such as Salmonella in foods and food-related environments. qPCR is a simple, sensitive, specific, and reproducible assay. Here, we describe the application of real-time PCR-based methods for a rapid (less than 24 h) detection of Salmonella in different types of foods fully compatible with the international standard for detection of Salmonella in food (ISO 6579-1:2017).


Assuntos
Reação em Cadeia da Polimerase em Tempo Real/métodos , Salmonella/genética , DNA Bacteriano/genética , Microbiologia de Alimentos/métodos , Sensibilidade e Especificidade
12.
Methods Mol Biol ; 2182: 33-38, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-32894484

RESUMO

Developed by 3M Company, 3M ™ Molecular Detection Assays-3M MDS-enable detection of Salmonella from advanced isothermal DNA amplification and bioluminescence detection technology. It can be used for a wide variety of products, including poultry, eggs, pet foods, and environmental samples, and results are obtained within about 24 h. In this chapter, all steps of the 3M MDS™ method for detection of Salmonella are described and detailed.


Assuntos
Técnicas Bacteriológicas/métodos , Microbiologia de Alimentos/métodos , Técnicas de Amplificação de Ácido Nucleico/métodos , Salmonella/genética , Animais , Ovos/microbiologia , Contaminação de Alimentos/análise , Aves Domésticas/microbiologia
13.
Methods Mol Biol ; 2182: 39-44, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-32894485

RESUMO

Polymerase chain reaction (PCR) and sequencing-based subtyping tools are useful for rapid analyses of Salmonella isolates. Here we describe the process of clustered regularly interspaced short palindromic repeat-multiple virulence locus sequence typing (CRISPR-MVLST) for Salmonella subtyping.


Assuntos
Repetições Palindrômicas Curtas Agrupadas e Regularmente Espaçadas/genética , Tipagem de Sequências Multilocus/métodos , Infecções por Salmonella/microbiologia , Salmonella/genética , Salmonella/isolamento & purificação , DNA Bacteriano/genética , Reação em Cadeia da Polimerase/métodos , Virulência/genética
14.
Methods Mol Biol ; 2182: 45-50, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-32894486

RESUMO

CRISPR typing is a newly developed method used to reveal the genetic relationship of bacterial isolates from different resources. For Salmonella, CRISPR typing can not only reveal the phylogenic difference among isolates belonging to the identical serotype, but also show good correspondence with Salmonella serotypes. Here we describe the protocol of CRISPR typing method used in Salmonella, and the approaches to analyze the genetic relationship among different strains.


Assuntos
Técnicas de Tipagem Bacteriana/métodos , Repetições Palindrômicas Curtas Agrupadas e Regularmente Espaçadas/genética , Salmonella/genética , Filogenia , Sorogrupo
15.
Methods Mol Biol ; 2182: 51-65, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-32894487

RESUMO

One of the main drawbacks in current methods for bacterium detection is their quantification at very low concentration level in complex specimens. Novel developments that are needed involve solid-phase preconcentration procedures which can be easily integrated with emerging technologies. Here, we describe the immunomagnetic separation (IMS) of Salmonella using magnetic carriers. Nano (300 nm) and micro (2.8 µm) sized magnetic particles are modified with anti-Salmonella antibody to preconcentrate the bacteria from the samples throughout an immunological reaction. The immunomagnetic separation can be easily coupled with downstream characterization and quantification methods, including classical culturing, molecular biology techniques such as PCR, immunoassays, confocal and scanning electron microscopy, and emerging technologies and rapid detection methods including biosensors, lateral flow, and microfluidic devices.


Assuntos
Separação Imunomagnética/métodos , Salmonella/isolamento & purificação , Imunoensaio/métodos , Dispositivos Lab-On-A-Chip , Limite de Detecção , Fenômenos Magnéticos , Magnetismo/métodos , Reação em Cadeia da Polimerase/métodos , Salmonella/genética
16.
Methods Mol Biol ; 2182: 187-196, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-32894497

RESUMO

Salmonella is recognized as a major human foodborne pathogen and threat to public health world widely. It is important to carry out epidemiological investigations to determine the primary sources of bacterial contamination. Pulsed-field gel electrophoresis (PFGE) is an important method of the molecular typing, and play an important role in tracking the sources of infection and epidemic control. The PFGE is currently considered as "gold standard" of molecular typing methods for bacterial foodborne pathogen. Here, we describe the PFGE protocol to type the Salmonella from pork.


Assuntos
Técnicas de Tipagem Bacteriana/métodos , Eletroforese em Gel de Campo Pulsado/métodos , Tipagem Molecular/métodos , Salmonella/genética , DNA Bacteriano/genética , Carne de Porco/microbiologia
17.
Int J Food Microbiol ; 336: 108902, 2021 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-33091757

RESUMO

Routine evaluation of the slaughter process is performed by the enumeration of the aerobic colony count, Enterobacteriaceae and Salmonella spp. on the carcass through destructive or non-destructive methods. With non-destructive methods, bacteria are counted from a minimum area of 100 cm2 in different sampling sites on the pork carcasses, and the results of these investigated areas are pooled to one value for the complete carcass evaluation (a total of 400 cm2). However, the composition of the bacterial community present on the different sampling areas remains unknown. The aim of the study was to characterize the microbial population present on four areas (ham, back, jowl and belly) of eight pork carcasses belonging to two different slaughterhouses through culture-dependent (Matrix-assisted laser desorption/ionization time-of-flight Mass Spectrometry MALDI-TOF MS, combined with 16S rRNA gene sequencing) and complementary culture-independent (16S rRNA amplicon sequencing) methods. The presence of Salmonella spp. and Y. enterocolitica was additionally assessed. Using MALDI-TOF MS, Staphylococcus, Pseudomonas, and Escherichia coli were found to dominate the bacterial cultures isolated from the 8 carcasses. Based on the 16S rRNA amplicon sequencing analyses however, no specific genus clearly dominated the bacterial community composition. By using this culture-independent method, the most abundant genera in microbial populations of the ham, back, jowl and belly were found to be similar, but important differences between the two slaughterhouses were observed. Thus, present data suggests that the indigenous bacterial population of individual animals is overruled by the microbial population of the slaughterhouse in which the carcass is handled. Also, our data suggests that sampling of only one carcass area by official authorities may be appropriate for the evaluation of the hygienic status of the carcasses and therefore of the slaughter process.


Assuntos
Matadouros , Bactérias/genética , Microbiologia de Alimentos , Carne/microbiologia , Animais , Bactérias/classificação , Bactérias/isolamento & purificação , Enterobacteriaceae/isolamento & purificação , Escherichia coli/genética , Pseudomonas/genética , RNA Ribossômico 16S/genética , Salmonella/genética , Staphylococcus/genética , Suínos
18.
PLoS One ; 15(12): e0244057, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33332438

RESUMO

BACKGROUND: Streptomycin is used as an epidemiological marker in monitoring programs for antimicrobial resistance in Salmonella serovars and indicates the presence of pentaresistance. However, comprehensive data on streptomycin resistant Salmonella among human, animal, and animal products is lacking in Ethiopia. In this review, we aimed to assess heterogeneity and pooled proportion of Salmonella serovars to streptomycin resistance among human, animal and animal products in Ethiopia. METHODS: We conducted a systematic review and meta-analysis of published literature from Ethiopia. We used the MEDLINE/ PubMed, Embase, Cochrane Library, and Google Scholar databases to identify genetic and phenotypic data on Salmonella isolates. To determine the heterogeneity and pooled proportion, we used metaprop commands and the random-effects model. Relative and cumulative frequencies were calculated to describe the overall preponderance of streptomycin resistance isolates after arcsine-transformed data. Metan funnel and meta-bias using a begg test were performed to check for publication bias. RESULTS: Overall, we included 1475 Salmonella serovars in this meta-analysis. The pooled proportion of streptomycin resistance was 47% (95% CI: 35-60%). Sub-group analysis by target population showed that the proportion of streptomycin resistance in Salmonella serovars was 54% (95% CI: 35-73%) in animal, 44% (95% Cl: 33-59%) in humans and 39% (95% CI: 24-55%) in animals products. The streptomycin resistant Salmonella serovars were statistically increasing from 0.35(95% CI: 0.12-0.58) in 2003 to 0.77(95% CI: 0.64-0.89) in 2018. The level of multidrug-resistant (MDR) Salmonella serovars was 50.1% in the meta-analysis. CONCLUSION: We found a high level of streptomycin resistance, including multidrug, Salmonella serovars among human, animals, and animal products. This resistance was significantly increasing in the last three decades (1985-2018). The resistance to streptomycin among Salmonella serovars isolated from animals was higher than humans. This mandates the continuous monitoring of streptomycin use and practicing one health approach to preventing further development of resistance in Ethiopia. REGISTRATION: We conducted a systematic review and meta-analysis after registration of the protocol in PROSPERO (CRD42019135116) following the MOOSE (Meta-Analysis of Observational Studies in Epidemiology).


Assuntos
Farmacorresistência Bacteriana , Salmonelose Animal/epidemiologia , Infecções por Salmonella/epidemiologia , Salmonella/patogenicidade , Animais , Antibacterianos/farmacologia , Etiópia , Humanos , Salmonella/efeitos dos fármacos , Salmonella/genética , Salmonella/isolamento & purificação , Infecções por Salmonella/microbiologia , Salmonelose Animal/microbiologia , Estreptomicina/farmacologia
19.
Mutat Res ; 786: 108338, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33339578

RESUMO

The Ames test has become one of the most commonly used tests to assess the mutagenic potential of medicinal plants since they have several biological activities and thus have been used in traditional medicine and in the pharmaceutical industry as a source of raw materials. Accordingly, this review aims to report previous use of the Ames test to evaluate the mutagenic potential of medicinal plants. A database was constructed by curating literature identified by a search on the electronic databases Medline (via Pubmed), Science Direct, Scopus, and Web of Science from 1975 to April 2020, using the following terms: "genotoxicity tests" OR "mutagenicity tests" OR "Ames test" AND "medicinal plants." From the research, 239 articles were selected, including studies of 478 species distributed across 111 botanical families, with Fabaceae, Asteraceae and Lamiaceae being the most frequent. It was identified that 388 species were non-mutagenic. Of these, 21% (83/388) showed antimutagenic potential, most notable in the Lamiaceae family. The results also indicate that 18% (90/478) of the species were mutagenic, of which 54% were mutagenic in the presence and absence of S9. Strains TA98 and TA100 showed a sensitivity of 93% in detecting plant extracts with mutagenic potential. However, the reliability of many reviewed studies regarding the botanical extracts may be questioned due to technical issues, such as testing being performed only in the presence or absence of S9, use of maximum doses below 5 mg/plate and lack of information on the cytotoxicity of tested doses. These methodological aspects additionally demonstrated that a discussion about the doses used in research on mixtures, such as the ones assessed with botanical extracts and the most sensitive strains employed to detect the mutagenic potential, should be included in a possible update of the guidelines designed by the regulatory agencies.


Assuntos
Microssomos/efeitos dos fármacos , Testes de Mutagenicidade/métodos , Mutagênicos/farmacologia , Plantas Medicinais/efeitos adversos , Salmonella/efeitos dos fármacos , Humanos , Medicina Tradicional , Plantas Medicinais/química , Salmonella/genética
20.
Wei Sheng Yan Jiu ; 49(5): 823-858, 2020 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-33070830

RESUMO

OBJECTIVE: Multiplex real-time PCR for the identification of 15 Salmonella serovars was developed. METHODS: Through the Salmonella genome comparison, 12 membrane proteins STM4497 gene can be used to identify 15 Salmonella serovars, and these 12 genes were respectively listed as A-L genes. Then primers were designed according to A-L gene conserved sequences, and then multiplex real-time PCR was established assessed with the evaluation of the limit detection, sensitivity, specificity, and repeatability. The 206 Salmonella strains were identified using multiplex real-time PCR with the comparison of the serum slide agglutination assay. RESULTS: The limit detection of multiplex PCR ranged from 1. 1×10~(-3)-1. 2×10~(-3) ng/µL. The target genes were 100% specificity, and the relative standard deviation was lower than 2. 97%. Compared with the serum slide agglutination assay, Kappa ranged 0. 92-1. 00. CONCLUSION: The multiplex real-time PCR can be used to identify 15 Salmonella serovars, which is rapid, accurate and specific.


Assuntos
Infecções por Salmonella , Salmonella , Humanos , Reação em Cadeia da Polimerase Multiplex , Reação em Cadeia da Polimerase em Tempo Real , Salmonella/genética , Infecções por Salmonella/diagnóstico , Sorogrupo
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