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1.
An Acad Bras Cienc ; 92 Suppl 1: e20180557, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32348408

RESUMO

In Brazil and in other countries of the world, studies have been conducted to identify Listeria monocytogenes in cattle meat that is preferably consumed undercooked and, when marketed without meeting strict phytosanitary requirements, may cause outbreaks of listeriosis. In the such, foodborne outbreaks, the methods used for the detection of the pathogen and the efficiency associated with them are crucial for the proper assessment. In this study, we used the techniques biochemical and molecular for identification of the L. monocytogenes isolated from 30 samples of the fresh beef, marketed in ten butchers' shop of the free-fair from a municipality from the Bahia, Brazil. The results obtained from biochemical tests (catalase, motility, ß-hemolysis and carbohydrate fermentation), as well as PCR analysis for the hly gene (hemolysin production is an important factor in the pathogenesis of listeriosis) revealed that 50% of butchers shops presented bovine meat contaminated with bacteria of the Listeria sp. and confirmed that 54.16% of the analyzed meat samples were positive for L. monocytogenes. This study highlights the importance of microbiological surveillance in free-fair to minimize the exposure of consumers to this foodborne pathogen.


Assuntos
DNA Bacteriano/análise , Proteínas Hemolisinas/genética , Listeria monocytogenes/isolamento & purificação , Produtos da Carne/microbiologia , Animais , Brasil , Bovinos , Microbiologia de Alimentos , Proteínas Hemolisinas/análise , Listeria monocytogenes/genética
3.
PLoS One ; 15(2): e0228956, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32040533

RESUMO

Listeria monocytogenes (L. monocytogenes) is a foodborne pathogen and the etiologic agent of listeriosis, which can be disseminated within the agricultural environment particularly soil and irrigation water, contaminate farm produce and cause high mortality and morbidity among vulnerable individuals. This study assessed the incidence and antibiogram of L. monocytogenes recovered from irrigation water and agricultural soil samples collected from Chris Hani and Amathole District Municipalities (DMs) in Eastern Cape Province, South Africa. The distribution of presumptive L. monocytogenes in irrigation water and agricultural soil samples was done using the standard plate count method, while polymerase chain reaction (PCR) was used to identify the isolates. The confirmed isolates were screened for 9 key virulence markers using PCR after which they were subjected to antibiotic susceptibility testing against 18 antibiotics used for the alleviation of listeriosis using the disk diffusion method. Relevant putative antibiotic resistance genes in the resistant variants were screened for using PCR. The distribution of L. monocytogenes in irrigation water samples was statistically significant (P ≤ 0.05) and ranged from log10 1.00 CFU/100ml to log10 3.75 CFU/100 ml. In agricultural soil samples, the distribution ranged significantly (P ≤ 0.05) from log10 2.10 CFU/g to log10 3.51 CFU/g. Of the 117 presumptive L. monocytogenes recovered from irrigation water samples and 183 presumptive L. monocytogenes isolated from agricultural soil samples, 8 (6.8%) and 12 (6.6%) isolates were confirmed respectively. Nine virulence genes including inlA, inlB, inlC, inlJ, actA, hlyA, plcA, plcB, and iap were detected in all the isolates. The proportion of the isolates exhibiting phenotypic resistance against the test antimicrobials followed the order: tetracycline (90%), doxycycline (85%), cefotaxime (80%), penicillin (80%), chloramphenicol (70%), linezolid (65%), erythromycin (60%) and trimethoprim/sulfamethoxazole (55%). The isolates exhibited multiple antibiotic resistance against 3 or more antibiotics and the MAR indices of all the multidrug isolates were ≥0.2. The isolates harboured antibiotic resistance genes including tetA, tetB, tetC, sulI, sulII, aadA, aac(3)-IIa and ESBLs including blaTEM, blaCTX-M group 9, blaVEB as well as AmpC. None of the isolates harboured the carbapenemases. We conclude that irrigation water and agricultural soil collected from Chris Hani and Amathole District Municipalities (DMs) in Eastern Cape Province of South Africa are reservoirs and potential transmission routes of multidrug-resistant L. monocytogenes to the food web and consequently threat to public health.


Assuntos
Listeria monocytogenes/isolamento & purificação , Microbiologia do Solo , Microbiologia da Água , Irrigação Agrícola , Reservatórios de Doenças/microbiologia , Farmacorresistência Bacteriana Múltipla/genética , Fazendas , Microbiologia de Alimentos , Genes Bacterianos , Humanos , Listeria monocytogenes/efeitos dos fármacos , Listeria monocytogenes/genética , Listeriose/transmissão , Testes de Sensibilidade Microbiana , África do Sul , Virulência/genética
4.
N Engl J Med ; 382(7): 632-643, 2020 02 13.
Artigo em Inglês | MEDLINE | ID: mdl-32053299

RESUMO

BACKGROUND: An outbreak of listeriosis was identified in South Africa in 2017. The source was unknown. METHODS: We conducted epidemiologic, trace-back, and environmental investigations and used whole-genome sequencing to type Listeria monocytogenes isolates. A case was defined as laboratory-confirmed L. monocytogenes infection during the period from June 11, 2017, to April 7, 2018. RESULTS: A total of 937 cases were identified, of which 465 (50%) were associated with pregnancy; 406 of the pregnancy-associated cases (87%) occurred in neonates. Of the 937 cases, 229 (24%) occurred in patients 15 to 49 years of age (excluding those who were pregnant). Among the patients in whom human immunodeficiency virus (HIV) status was known, 38% of those with pregnancy-associated cases (77 of 204) and 46% of the remaining patients (97 of 211) were infected with HIV. Among 728 patients with a known outcome, 193 (27%) died. Clinical isolates from 609 patients were sequenced, and 567 (93%) were identified as sequence type 6 (ST6). In a case-control analysis, patients with ST6 infections were more likely to have eaten polony (a ready-to-eat processed meat) than those with non-ST6 infections (odds ratio, 8.55; 95% confidence interval, 1.66 to 43.35). Polony and environmental samples also yielded ST6 isolates, which, together with the isolates from the patients, belonged to the same core-genome multilocus sequence typing cluster with no more than 4 allelic differences; these findings showed that polony produced at a single facility was the outbreak source. A recall of ready-to-eat processed meat products from this facility was associated with a rapid decline in the incidence of L. monocytogenes ST6 infections. CONCLUSIONS: This investigation showed that in a middle-income country with a high prevalence of HIV infection, L. monocytogenes caused disproportionate illness among pregnant girls and women and HIV-infected persons. Whole-genome sequencing facilitated the detection of the outbreak and guided the trace-back investigations that led to the identification of the source.


Assuntos
Surtos de Doenças , Doenças Transmitidas por Alimentos/epidemiologia , Listeria monocytogenes/isolamento & purificação , Listeriose/epidemiologia , Produtos da Carne/microbiologia , Adolescente , Adulto , Idoso , Técnicas de Tipagem Bacteriana , Estudos de Casos e Controles , Feminino , Doenças Transmitidas por Alimentos/etiologia , Doenças Transmitidas por Alimentos/mortalidade , Infecções por HIV/complicações , HIV-1 , Humanos , Recém-Nascido , Listeria monocytogenes/genética , Listeriose/etiologia , Listeriose/mortalidade , Masculino , Produtos da Carne/efeitos adversos , Pessoa de Meia-Idade , Gravidez , Complicações Infecciosas na Gravidez/epidemiologia , Recall e Retirada de Produto , Distribuição por Sexo , África do Sul/epidemiologia , Sequenciamento Completo do Genoma , Adulto Jovem
5.
Zhonghua Yu Fang Yi Xue Za Zhi ; 54(2): 175-180, 2020 Feb 06.
Artigo em Chinês | MEDLINE | ID: mdl-32074706

RESUMO

Objective: To analyze the molecular characteristics of Listeria monocytogenes strains from ready-to eat food in China. Methods: A total of 239 Listeria monocytogenes strains isolated from ready-to-eat food in 2017, all strains underwent whole-genome sequencing (WGS) , and comparisons uncovered population structure derived from lineages, clonal complex, serogroups, antimicrobial susceptibility and virulence, which were inferred in silico from the WGS data. Core genome multilocus sequence typing was used to subtype isolates. Results: All strains were categorized into three different lineages, lineage Ⅱ was the predominant types in food, and IIa was the main serogroups. CC8, CC101 and CC87 were the first three prevalent CCs among 23 detected CCs, accounting for 49.4%. Only 4.6% (11 isolates) of tested strains harbored antibiotic resistance genes, which were mostly trimethoprim genes (7 isolates, 2.9%). All strains were positive for LIPI-1, and only a part of strains harbored LIPI-3 and LIPI-4, accounting for 13.8% (33 isolates) and 14.2% (34 isolates), respectively. ST619 carried both LIPI-3 and LIPI-4. 51.5% (123 isolates) of strains carried SSI-1, and all CC121 strains harbored SSI-2. Different lineages, serogroups and CCs can be separated obviously through cgMLST analysis, and 24 sublineages were highly concordant with CCs. Conclusion: Ⅱa was the main serogroups in ready-to-eat food isolates in China; CC8, CC101 and CC87 were the prevalent CCs, and CC87 isolates was hypervirulent isolates, cgMLST method can be adopted for prospective foodborne disease surveillance and outbreaks detection.


Assuntos
Microbiologia de Alimentos , Listeria monocytogenes/isolamento & purificação , Listeriose/microbiologia , China/epidemiologia , Humanos , Listeriose/epidemiologia
6.
Food Microbiol ; 87: 103367, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-31948615

RESUMO

Listeria monocytogenes is an important foodborne pathogen, causative agent of listeriosis. The epidemiology and persistence of this bacterium in meat processing plants may be related to its serotype, so it is of utmost importance to carry out a correct differentiation of L. monocytogenes serotypes. The objective of this study was to develop a unique quadruplex real-time quantitative PCR (qPCR) method able to differentiate the four most predominant and worrying L. monocytogenes serotypes (1/2a, 1/2b, 1/2c and 4b) in isolates from meat processing plants and ready-to-eat (RTE) dry-cured meat products. The design of specific primers and probes was based on the lmo0737, lmo0308, ORFC (locus genomically equivalent to gltA-gltB) and ORF2110 genes. A qPCR based on a fragment of the 16S rRNA gene was used to ensure the amplification of Listeria spp. genomic DNA. The standard curves showed efficiency values ranging between 92.3% and 105.8% and, R2 values > 0.98. The specificity of the method was also confirmed by the comparison of the results with those obtained by a previously reported conventional multiplex PCR. In addition, none of the strains which were not ascribed to L. monocytogenes amplified any of the target genes related to the four major serotypes of this pathogenic species. The qPCR, therefore, provides a sensitive, specific and rapid tool for identifying the L. monocytogenes serotypes 1/2a, 1/2b, 1/2c and 4b. This method could be very useful for identifying sources of L. monocytogenes contamination in the meat industry or for epidemiological monitoring of persistent strains throughout the processing of RTE meat products.


Assuntos
Listeria monocytogenes/isolamento & purificação , Carne/microbiologia , Reação em Cadeia da Polimerase em Tempo Real/métodos , Primers do DNA/genética , DNA Bacteriano/genética , Contaminação de Alimentos/análise , Manipulação de Alimentos/instrumentação , Listeria monocytogenes/classificação , Listeria monocytogenes/genética , Produtos da Carne/microbiologia , RNA Ribossômico 16S/genética , Sorogrupo
7.
Int J Food Microbiol ; 314: 108360, 2020 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-31678600

RESUMO

Due to a higher probability for violation of hygiene measures, reconstruction work is a substantial food safety challenge for food business operators (FBOs). Here, we monitored a Listeria monocytogenes contamination scenario during a timely enduring reconstruction period that aimed at an expansion of the main building of a leading meat processing facility. Reconstruction took place while food production was ongoing. We used a longitudinal sampling scheme targeting 40 floor water drains distributed over the food processing environment (FPE) over a five year period. The population structure of L. monocytogenes was determined by PCR-serogrouping, pulsed-field gel electrophoresis (PFGE) and multi-locus sequence typing (MLST). While the first sampling deciphered a baseline of contamination (45%), intensified sanitation measures decreased L. monocytogenes prevalence before commencement of work (5%). The reconstruction activities increased the prevalence of L. monocytogenes in the FPE (20.5%) and changed the population structure to a higher proportion of disease-associated genotypes (61%). During the first sampling ST121 was prevalent throughout the FPE, even in the packaging area. After the second and third sampling, following increased application of hypochlorite during sanitation, ST121 was only present in the raw material preparation area. A resilient flora was detected during three sampling events (ST8, ST9 and ST37) which might have not been exposed to daily cleaning in the floor drains. After the accomplishment of reconstruction work, the L. monocytogenes population structure shifted to the condition initially found (45% and 20.5% during the first and sixth sampling event). This paper indicates that reconstruction phases are high risk episodes for food safety in FPEs. Special precautions must be taken to avoid cross-contamination of products since reconstruction is usually ongoing for extended periods of time.


Assuntos
Monitoramento Ambiental , Manipulação de Alimentos , Microbiologia de Alimentos/estatística & dados numéricos , Listeria monocytogenes/isolamento & purificação , Carne/microbiologia , Animais , Arquitetura de Instituições de Saúde , Contaminação de Alimentos/prevenção & controle , Inocuidade dos Alimentos , Genótipo , Listeria monocytogenes/classificação , Listeria monocytogenes/genética
8.
Int J Food Microbiol ; 312: 108358, 2020 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-31655356

RESUMO

Meat products are commonly regarded as one of the main sources of human listeriosis caused by Listeria monocytogenes. The objective of this study was to estimate the prevalence of L. monocytogenes in a range of meat products from 24 different Chinese regions by using meta-analysis of literature data and a novel sensitivity analysis approach. A total of 112 publications from five databases, published between 1 January 2007 and 31 December 2017, were systematically selected for relevance and covered meat products sampled between 2000 and 2016. Estimated by the random-effects model, the pooled prevalence of L. monocytogenes was 8.5% (95% CI: 7.1%-10.3%) in raw meats and 3.2% (95% CI: 2.7%-3.9%) in ready-to-eat (RTE) meats. The prevalence differed from high to low among raw meats including prefabricated raw meats 12.6% (95% CI: 6.9%-21.7%), fresh pork 11.4% (95% CI: 8.6%-14.9%), fresh beef 9.1% (95% CI: 6.3%-13.0%), fresh poultry 7.2% (95% CI:4.9%-10.4%), frozen raw meats 7.2% (95% CI: 5.7%-9.0%), and fresh mutton 5.4% (95% CI: 2.5%-11.0%). A higher L. monocytogenes prevalence level was shown in the meat products from central and northeastern China provincial regions. The entropy-based sensitivity analysis utilized in the meta-analysis indicated that the sampling period and location were two critical factors influencing the prevalence level of L. monocytogenes in meat products. A better understanding of differences in prevalence levels per geographic region and between meat product sources may allow the competent authorities, industry, and other relevant stakeholders to tailor their interventions to control the occurrence of L. monocytogenes in meat products effectively.


Assuntos
Contaminação de Alimentos/análise , Microbiologia de Alimentos , Listeria monocytogenes/isolamento & purificação , Produtos da Carne/microbiologia , Aves Domésticas/microbiologia , Animais , Bovinos , China , Humanos , Listeriose/epidemiologia , Prevalência , Ovinos , Suínos
9.
Arch Virol ; 165(3): 715-718, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31873766

RESUMO

In the present study, we evaluated the degree of contamination of fresh vegetables, cheeses and jellies from disaster area in Brazil with bacteria and enteric viruses. Food samples (n = 350) were tested for Escherichia coli, Salmonella spp., Listeria monocytogenes, Staphylococcus spp., and enteric viruses (rotavirus A (RVA), human adenovirus (HAdV), hepatitis A virus (HAV), and human norovirus (HNoV). E. coli was present in 56% of the samples, Salmonella spp. was present in 14% of the samples, L. monocytogenes and Staphylococcus spp. (coagulase-positive) were present in 36% of the samples. The enteric viruses RVA and HAdV were detected in cheeses and vegetables.


Assuntos
Queijo/microbiologia , Contaminação de Alimentos/análise , Verduras/microbiologia , Adenovírus Humanos/isolamento & purificação , Brasil , Escherichia coli/isolamento & purificação , Fazendas , Vírus da Hepatite A/isolamento & purificação , Humanos , Listeria monocytogenes/isolamento & purificação , Norovirus/isolamento & purificação , Rotavirus/isolamento & purificação , Salmonella/isolamento & purificação , Staphylococcus/isolamento & purificação
10.
J Dairy Sci ; 103(1): 176-178, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31733864

RESUMO

Unpasteurized milk can contain harmful bacteria such as Listeria monocytogenes. In 2016, the US Food and Drug Administration notified the Centers for Disease Control and Prevention (Atlanta, GA) that L. monocytogenes isolated from unpasteurized chocolate milk from a Pennsylvania dairy was closely related, by whole-genome sequencing, to L. monocytogenes isolates collected from blood specimens of 2 patients (in California and Florida) in 2014. The California and Florida patients consumed unpasteurized milk from the Pennsylvania dairy. Both were >65 yr old and were hospitalized in 2014; the Florida patient died. Isolates from the 2 patients had indistinguishable pulsed-field gel electrophoresis patterns and were closely related by whole-genome multilocus sequence typing analysis (by 2 alleles) to the isolate from unpasteurized chocolate milk produced by the Pennsylvania dairy in 2015. Together, epidemiologic and laboratory information indicated a common origin. This is the first multistate listeriosis outbreak linked to unpasteurized milk in the United States detected using whole-genome multilocus sequence analysis.


Assuntos
Surtos de Doenças , Microbiologia de Alimentos , Listeria monocytogenes/genética , Listeriose/epidemiologia , Leite/microbiologia , Sequenciamento Completo do Genoma , Animais , California/epidemiologia , Eletroforese em Gel de Campo Pulsado/veterinária , Florida/epidemiologia , Humanos , Listeria monocytogenes/isolamento & purificação , Listeriose/microbiologia , Tipagem de Sequências Multilocus/veterinária , Pennsylvania/epidemiologia , Estudos Retrospectivos , Estados Unidos/epidemiologia
11.
Pol J Microbiol ; 68(3): 353-369, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31880881

RESUMO

Listeria monocytogenes is the etiological factor of listeriosis. The main source of these organisms is food, including dairy products. The aim was to determine the multiple correlations between the drug susceptibility, virulence genes (VGs), and biofilm formation on silicone teat cups of milk-borne and human L. monocytogenes strains. The spread of L. monocytogenes via contaminated teat rubbers was assessed. The L. monocytogenes strains recovered from milk (18), human blood (10), and the reference strain ATCC®19111™ were used in the study. Penicillin resistance was the most prevalent resistance in the milk isolates (n=8; 44.4%), whereas among clinical strains erythromycin resistance was predominating - (n=6; 60%). The most frequent VGs among strains isolated from milk were hlyA (100%) and plcB (100%) whereas in strains isolated from blood - hlyA (100%) and prfA (90%). All tested VGs were present in 50% of blood isolates and 11% of milk-borne strains. The strains isolated from milk formed a significantly stronger biofilm. The strains with more numerous virulence genes were resistant to more antibiotics and formed a stronger biofilm. It was shown that contaminated teat cups might contribute to the transmission of L. monocytogenes in the herd. It seems reasonable to monitor the occurrence of L. monocytogenes biofilm in a dairy processing environment.Listeria monocytogenes is the etiological factor of listeriosis. The main source of these organisms is food, including dairy products. The aim was to determine the multiple correlations between the drug susceptibility, virulence genes (VGs), and biofilm formation on silicone teat cups of milk-borne and human L. monocytogenes strains. The spread of L. monocytogenes via contaminated teat rubbers was assessed. The L. monocytogenes strains recovered from milk (18), human blood (10), and the reference strain ATCC®19111™ were used in the study. Penicillin resistance was the most prevalent resistance in the milk isolates (n=8; 44.4%), whereas among clinical strains erythromycin resistance was predominating ­ (n=6; 60%). The most frequent VGs among strains isolated from milk were hlyA (100%) and plcB (100%) whereas in strains isolated from blood ­ hlyA (100%) and prfA (90%). All tested VGs were present in 50% of blood isolates and 11% of milk-borne strains. The strains isolated from milk formed a significantly stronger biofilm. The strains with more numerous virulence genes were resistant to more antibiotics and formed a stronger biofilm. It was shown that contaminated teat cups might contribute to the transmission of L. monocytogenes in the herd. It seems reasonable to monitor the occurrence of L. monocytogenes biofilm in a dairy processing environment.


Assuntos
Sangue/microbiologia , Listeria monocytogenes/isolamento & purificação , Listeriose/microbiologia , Leite/microbiologia , Animais , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Biofilmes , Bovinos , Humanos , Listeria monocytogenes/classificação , Listeria monocytogenes/genética , Listeria monocytogenes/fisiologia , Listeriose/transmissão , Filogenia , Fatores de Virulência/genética , Fatores de Virulência/metabolismo
12.
Rev Chilena Infectol ; 36(5): 585-590, 2019 Oct.
Artigo em Espanhol | MEDLINE | ID: mdl-31859799

RESUMO

BACKGROUND: Listeria monocytogenes is a foodborne pathogen that causes listeriosis, a disease that can present as febrile gastroenteritis or as an invasive form that has high mortality rates. So far, the genetic diversity of strains of L. monocytogenes isolated from patients, foods and environmental sources in Chile has been poorly studied. AIM: To characterize genetically L. monocytogenes strains received by the Institute of Public Health of Chile (ISP) between 2007 and 2014. METHODS: We selected 94 strains of L. monocytogenes corresponding to 94 different pulsotypes identified by pulsed field gel electrophoresis (PFGE), DNA was extracted and serotyping was performed by polymerase chain reaction (PCR) and multilocus sequence typing (MLST). RESULTS: The most common serotype was 4b (55.3%), followed by serotypes 1/2a (25.5%), 1/2b (17%) and 1/2c (2.2%). 32 sequence-type (ST) were identified, of which 4 were new, and the predominant ones were ST1 (28.7%) and ST2 (13.8%). All the strains of L. monocytogenes were grouped in Lineages I and II. CONCLUSIONS: A great genetic variability was observed in the strains of L. monocytogenes analyzed, being predominant the ST1 and ST2, both belonging to Lineage I. Our results contribute to know the population structure of this pathogen in Chile and its presence in clinical samples, food and the environment.


Assuntos
Listeria monocytogenes/genética , Listeria monocytogenes/isolamento & purificação , Chile , Eletroforese em Gel de Campo Pulsado , Microbiologia Ambiental , Microbiologia de Alimentos , Variação Genética , Humanos , Listeriose/microbiologia , Tipagem de Sequências Multilocus , Reação em Cadeia da Polimerase , Sorotipagem , Fatores de Tempo
13.
BMC Vet Res ; 15(1): 467, 2019 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-31864375

RESUMO

BACKGROUND: Listeria monocytogenes is a promising therapeutic vaccine vector for cancer immunotherapy. Although highly attenuated, three cases of systemic listeriosis have been reported in people following treatment with Listeria-based therapeutic vaccines. This complication has thus far not been reported in canine patients. CASE PRESENTATION: A dog previously diagnosed with osteoblastic osteosarcoma was presented for care following administration of three doses of the Canine Osteosarcoma Vaccine-Live Listeria Vector. On routine staging chest radiographs, mild sternal lymphadenopathy and a right caudoventral thoracic mass effect were noted. Further evaluation of the mass effect with computed tomography and ultrasound revealed a cavitated mass associated with the 7th right rib. Aspirates of the mass cultured positive for Listeria monocytogenes. The mass and associated ribs were surgically removed. Histopathology was consistent with metastatic osteoblastic osteosarcoma. Treatment was continued with doxorubicin chemotherapy and at the time of publication, the dog was alive over 1 year following diagnosis with no evidence of further disease progression. Genotyping of the abscess-derived L. monocytogenes was consistent with the vaccine strain. CONCLUSIONS: This case represents the first veterinary case to describe development of a Listeria abscess following administration of a Listeria-based therapeutic vaccine.


Assuntos
Abscesso/veterinária , Neoplasias Ósseas/veterinária , Listeria monocytogenes/isolamento & purificação , Listeriose/veterinária , Osteossarcoma/veterinária , Abscesso/microbiologia , Animais , Vacinas Bacterianas/efeitos adversos , Neoplasias Ósseas/prevenção & controle , Neoplasias Ósseas/secundário , Cães , Imunoterapia/efeitos adversos , Imunoterapia/veterinária , Listeria monocytogenes/genética , Listeriose/diagnóstico por imagem , Listeriose/microbiologia , Osteossarcoma/prevenção & controle , Osteossarcoma/secundário
14.
Anal Bioanal Chem ; 411(29): 7899-7906, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31745614

RESUMO

The presence of Salmonella in natural freshwater and drinking water is a leading cause of intestinal illness all over the world; thus, the detection of Salmonella in water is of great importance to public health. The objective of this study is to develop a rapid screening method for the detection of Salmonella enterica serovar Enteritidis in water involving surface-enhanced Raman spectroscopy (SERS), aptamers, and filtration. SERS offers a great alternative to traditional methods of pathogen detection, with a simplified detection assay and shortened detection time. The specific capturing and labeling of Salmonella Enteritidis are realized by a specific single-stranded DNA aptamer, which is modified with an additional chain of adenine and fluorescein (FAM) and used as presence/absence indicator of Salmonella Enteritidis. By incorporating a vacuum filtration system, bacterial cells recognized by the specific aptamer are concentrated onto a membrane. With additional filtration of gold nanoparticles, the aptamer signals were captured and used to construct a SERS mapping indicating the presence and absence of target bacterial strains with potential quantitative capability. The specificity of the method was validated by using other strains of bacteria such as Escherichia coli and Listeria monocytogenes. The sensitivity of the method goes down to 103 CFU/mL for 1 mL of sample with a total detection and analyzing time within 3 h. This study demonstrates the capability of the filtration-based SERS platform for detecting Salmonella Enteritidis in various aqueous matrices such as distilled water and rinsing water from fresh produce with high selectivity and sensitivity. Graphical abstract.


Assuntos
Filtração/métodos , Salmonella enteritidis/isolamento & purificação , Análise Espectral Raman/métodos , Escherichia coli/isolamento & purificação , Limite de Detecção , Listeria monocytogenes/isolamento & purificação , Reprodutibilidade dos Testes , Microbiologia da Água
15.
Medicine (Baltimore) ; 98(45): e17885, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31702663

RESUMO

RATIONALE: Endograft infection following endovascular stent for aortic aneurysm is rare (0.6%-3%), but it results in high mortality rate of 25% to 88%. PATIENT CONCERNS: A 66-year-old hypertensive man underwent an endovascular stent graft for abdominal aortic aneurysm 18 months ago. Recurrent episodes of fever, chills, and abdominal fullness occurred 6 months ago before this admission. Laboratory data showed 20 mg/dL of C-reactive protein and abdominal computed tomography (CT) revealed an aortic endoleak at an urban hospital, so 4-day course of intravenous (IV) amoxicillin/clavulanic acid was given and he was discharged after fever subsided. He was admitted to our hospital due to fever, chills, and watery diarrhea for 1 day. Abdominal CT showed left psoas abscess associated with endograft infection. Blood culture grew Listeria monocytogenes. DIAGNOSIS: Left psoas abscess associated with endograft infection caused by bacteremia of Listeria monocytogenes. INTERVENTIONS: IV ampicillin with 8 days of synergistic gentamicin was prescribed and it created satisfactory response. Ampicillin was continued for 30 days and then shifted to IV co-trimoxazole for 12 days. OUTCOMES: He remained asymptomatic with a decline of CRP to 0.36 mg/dL and ESR to 39 mm/h. He was discharged on the 44th hospital day. Orally SMX/TMP was prescribed for 13.5 months. LESSONS: Only few cases of aortic endograft infection caused by Listeria monocytogenes had been reported. In selected cases, particularly with smoldering presentations and high operative risk, endograft retention with a prolonged antimicrobial therapy seem plausible as an initial therapeutic option, complemented with percutaneous drainage or surgical debridement if necessary.


Assuntos
Listeria monocytogenes/isolamento & purificação , Infecções Relacionadas à Prótese/diagnóstico , Abscesso do Psoas/diagnóstico , Idoso , Ampicilina/uso terapêutico , Antibacterianos/uso terapêutico , Aneurisma da Aorta Abdominal/cirurgia , Implante de Prótese Vascular/efeitos adversos , Gentamicinas/uso terapêutico , Humanos , Masculino , Infecções Relacionadas à Prótese/tratamento farmacológico , Abscesso do Psoas/tratamento farmacológico , Abscesso do Psoas/etiologia , Tomografia Computadorizada por Raios X
16.
Pak J Pharm Sci ; 32(4): 1485-1494, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31608866

RESUMO

This study sheds the light on the presence of (some) food-borne pathogens in raw market milk in Mansoura city, (Egypt) using several techniques for isolation and identification including serology and PCR. It determines, further, the susceptibility of the isolated pathogens to some antimicrobial agents and natural oils, including watercress, basil, parsley, and hot green pepper oils. From 100 milk samples, 22 Escherichia coli isolates harboured stx1, stx2 and/or eae genes. Additionally, 17 Listeria monocytogenes (L. monocytogenes) isolates harboured hylA gene. Moreover, other related pathogens such as Shigella flexneri and Klebsiella pneumoniae were also detected. Antimicrobial susceptibility testing showed that E. coli strains were (completely) resistant to amoxicillin and sulfamethoxazole-trimethoprim but highly sensitive to gentamicin. L. monocytogenes strains showed complete resistance against oxytetracycline while the highest percentage of sensitivity was observed against norfloxacin. This study has also proved the following: L. monocytogenes was susceptible to all of the investigated oils, Klebsiella pneumoniae was sensitive to two types of oils, but E. coli and Shigella flexneri were resistant to all oils. In conclusion, it is risky to consume unpasteurized milk. Further, some natural oils (e.g. parsley and hot green pepper oils) can successfully be used as food additives to control the presence of some pathogens in milk.


Assuntos
Antibacterianos/farmacologia , Microbiologia de Alimentos , Leite/microbiologia , Óleos Vegetais/farmacologia , Adesinas Bacterianas/genética , Animais , Farmacorresistência Bacteriana/efeitos dos fármacos , Egito , Escherichia coli/efeitos dos fármacos , Escherichia coli/genética , Escherichia coli/isolamento & purificação , Proteínas de Escherichia coli/genética , Doenças Transmitidas por Alimentos/microbiologia , Klebsiella pneumoniae/efeitos dos fármacos , Klebsiella pneumoniae/isolamento & purificação , Listeria monocytogenes/efeitos dos fármacos , Listeria monocytogenes/genética , Listeria monocytogenes/isolamento & purificação , Testes de Sensibilidade Microbiana , Toxina Shiga I/genética , Toxina Shiga II/genética , Shigella flexneri/efeitos dos fármacos
18.
Nat Commun ; 10(1): 4283, 2019 09 30.
Artigo em Inglês | MEDLINE | ID: mdl-31570766

RESUMO

The foodborne pathogen Listeria monocytogenes (Lm) is a highly heterogeneous species and currently comprises of 4 evolutionarily distinct lineages. Here, we characterize isolates from severe ovine listeriosis outbreaks that represent a hybrid sub-lineage of the major lineage II (HSL-II) and serotype 4h. HSL-II isolates are highly virulent and exhibit higher organ colonization capacities than well-characterized hypervirulent strains of Lm in an orogastric mouse infection model. The isolates harbour both the Lm Pathogenicity Island (LIPI)-1 and a truncated LIPI-2 locus, encoding sphingomyelinase (SmcL), a virulence factor required for invasion and bacterial translocation from the gut, and other non-contiguous chromosomal segments from another pathogenic species, L. ivanovii. HSL-II isolates exhibit a unique wall teichoic acid (WTA) structure essential for resistance to antimicrobial peptides, bacterial invasion and virulence. The discovery of isolates harbouring pan-species virulence genes of the genus Listeria warrants global efforts to identify further hypervirulent lineages of Lm.


Assuntos
Listeria monocytogenes/genética , Listeriose/microbiologia , Animais , Células CACO-2 , Genoma Bacteriano , Genômica , Cabras/microbiologia , Humanos , Listeria monocytogenes/isolamento & purificação , Listeria monocytogenes/patogenicidade , Camundongos , Filogenia , Suínos/microbiologia , Virulência
19.
BMC Infect Dis ; 19(1): 893, 2019 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-31655547

RESUMO

BACKGROUND: Neonatal listeriosis is a rare but severe disease manifesting as septicemia and central nervous system (CNS) infections with a high fatality rate of around 20 to 30%. Whole genome sequencing (WGS) is a promising technique for pathogen identification and infection source tracing with its high resolution. CASE PRESENTATION: A case of neonatal sepsis with listeriosis was reported with positive blood culture for Listeria monocytogenes. The case was investigated to confirm the vertical transmission of the infection and identify the potential food source of the maternal L. monocytogenes infection using WGS. L. monocytogenes was isolated from the neonate's blood sample the day after caesarean delivery and from the mother's genital and pudenda swab samples 5 days and 13 days after caesarean delivery. WGS showed that the isolate from the neonate was identical to the genome type of the isolates from the mother, with only one of the 4 isolates from the mother differing by one single nucleotide polymorphism (SNP). By WGS, one L. monocytogenes isolate from a ready-to-eat (RTE) meat sample in the patients' community market shared the same sequence type but was ruled out as the cause of infection, with 57 SNP differences to the strain causing the maternal-neonatal infection. The food isolate also carried a novel plasmid pLM1686 that harbored heavy metal resistance genes. After caesarean section, the mother was treated with a third generation cephalosporin which L. monocytogenes is naturally resistant to, which may explain why genital and pudenda swabs were still culture-positive for L. monocytogenes 13 days after delivery. CONCLUSIONS: Genital swab culture for L. monocytogenes had been informative in the diagnosis of maternal listeriosis in this case. The high resolution of WGS confirmed the maternal-neonatal transmission of L. monocytogenes infection and ruled out the L. monocytogenes contaminated RTE meat from the local market as the direct source of the mother's infection.


Assuntos
Listeriose/diagnóstico , Listeriose/genética , Sepse Neonatal/microbiologia , China , Feminino , Contaminação de Alimentos , Microbiologia de Alimentos , Humanos , Recém-Nascido , Doenças do Recém-Nascido/microbiologia , Listeria monocytogenes/genética , Listeria monocytogenes/isolamento & purificação , Listeriose/transmissão , Carne/microbiologia , Sepse Neonatal/tratamento farmacológico , Polimorfismo de Nucleotídeo Único , Gravidez , Sequenciamento Completo do Genoma , Adulto Jovem
20.
Braz J Microbiol ; 50(4): 1063-1073, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31478167

RESUMO

Listeria monocytogenes is one of the most important foodborne pathogens and is a causal agent of listeriosis in humans and animals. The aim of this study was to determine the prevalence, serogroups, antibiotic susceptibility, virulence factor genes, and genetic relatedness of L. monocytogenes strains isolated from 500 poultry samples in Turkey. The isolation sources of 103 L. monocytogenes strains were retail markets (n = 100) and slaughterhouses (n = 3). L. monocytogenes strains were identified as serogroups 1/2a-3a (75.7%, lineage I), 1/2c-3c (14.56%, lineage I), 1/2b-3b-7 (5.82%, lineage II), 4a-4c (2.91%, lineage III), and 4b-4d-4e (0.97%, lineage III). Most of the L. monocytogenes strains (93.2%) were susceptible to the antibiotics tested. PCR analysis indicated that the majority of the strains (95% to 100%) contained most of the virulence genes (hylA, plcA, plcB, prfA, mpl, actA, dltA, fri, flaA inlA, inlC, and inlJ). Pulsed-field gel electrophoresis (PFGE) demonstrated that there were 18 pulsotypes grouped at a similarity of > 90% among the strains. These results indicate that it is necessary to prevent the presence of L. monocytogenes in the poultry-processing environments to help prevent outbreaks of listeriosis and protect public health.


Assuntos
Listeria monocytogenes/genética , Listeria monocytogenes/isolamento & purificação , Listeriose/veterinária , Doenças das Aves Domésticas/microbiologia , Matadouros/economia , Animais , Antibacterianos/farmacologia , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Galinhas , Microbiologia de Alimentos , Listeria monocytogenes/classificação , Listeria monocytogenes/efeitos dos fármacos , Listeriose/epidemiologia , Listeriose/microbiologia , Doenças das Aves Domésticas/economia , Doenças das Aves Domésticas/epidemiologia , Prevalência , Turquia/epidemiologia , Fatores de Virulência/genética , Fatores de Virulência/metabolismo
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