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1.
Gut Pathog ; 16(1): 57, 2024 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-39370525

RESUMO

Classification of pathogenic E. coli has been focused either in mammalian host or infection site, which offers limited resolution. This review presents a comprehensive framework for classifying all E. coli branches within a single, unifying figure. This approach integrates established methods based on virulence factors, serotypes and clinical syndromes, offering a more nuanced and informative perspective on E. coli pathogenicity. The presence of the LEE island in pathogenic E. coli is a key genetic marker differentiating EHEC from STEC strains. The coexistence of stx and eae genes within the bacterial genome is a primary characteristic used to distinguish STEC from other pathogenic E. coli strains. The presence of the inv plasmid, Afa/Dr adhesins, CFA-CS-LT-ST and EAST1 are key distinguishing features for identifying pathogenic E. coli strains belonging to EIEC, DAEC, ETEC and EAEC pathotypes respectively. Food microbiological criteria differentiate pathogenic E. coli in food matrices. 'Zero-tolerance' applies to most ready-to-eat (RTE) foods due to high illness risk. Non-RTE foods' roles may allow limited E. coli presence, which expose consumers to potential risk; particularly from the concerning Shiga toxin-producing E. coli (STEC) strains, which can lead to life-threatening complications in humans, including haemolytic uremic syndrome (HUS) and even death in susceptible individuals. These findings suggest that decision-makers should consider incorporating the separate detection of STEC serotypes into food microbiological criteria, in addition to existing enumeration methods. Contamination of STEC is mainly linked to food consumption, therefore, outbreaks of E. coli STEC has been reviewed here and showed a link also to water as a potential contamination route. Since their discovery in 1982, over 39,787 STEC cases associated with 1,343 outbreaks have been documented. The majority of these outbreaks occurred in the Americas, followed by Europe, Asia and Africa. The most common serotypes identified among the outbreaks were O157, the 'Big Six' (O26, O45, O103, O111, O121, and O145), and other serotypes such as O55, O80, O101, O104, O116, O165, O174 and O183. This review provides valuable insights into the most prevalent serotypes implicated in STEC outbreaks and identifies gaps in microbiological criteria, particularly for E. coli non-O157 and non-Big Six serotypes.

2.
Front Microbiol ; 15: 1364026, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38562479

RESUMO

Shiga toxin (Stx)-producing Escherichia coli (STEC) of non-O157:H7 serotypes are responsible for global and widespread human food-borne disease. Among these serogroups, O26, O45, O103, O111, O121, and O145 account for the majority of clinical infections and are colloquially referred to as the "Big Six." The "Big Six" strain panel we sequenced and analyzed in this study are reference type cultures comprised of six strains representing each of the non-O157 STEC serogroups curated and distributed by the American Type Culture Collection (ATCC) as a resource to the research community under panel number ATCC MP-9. The application of long- and short-read hybrid sequencing yielded closed chromosomes and a total of 14 plasmids of diverse functions. Through high-resolution comparative phylogenomics, we cataloged the shared and strain-specific virulence and resistance gene content and established the close relationship of serogroup O26 and O103 strains featuring flagellar H-type 11. Virulence phenotyping revealed statistically significant differences in the Stx-production capabilities that we found to be correlated to the strain's individual stx-status. Among the carried Stx1a, Stx2a, and Stx2d phages, the Stx2a phage is by far the most responsive upon RecA-mediated phage mobilization, and in consequence, stx2a + isolates produced the highest-level of toxin in this panel. The availability of high-quality closed genomes for this "Big Six" reference set, including carried plasmids, along with the recorded genomic virulence profiles and Stx-production phenotypes will provide a valuable foundation to further explore the plasticity in evolutionary trajectories in these emerging non-O157 STEC lineages, which are major culprits of human food-borne disease.

3.
Arch Sex Behav ; 50(8): 3843-3852, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34671873

RESUMO

Growing research interest in asexuality has led to several notable findings around the differences between asexual people and those with other sexual orientations. These findings have recently extended to personality, but questions remain around differences in personality between asexual people and others. Furthermore, qualitative and quantitative research disagrees about whether asexual people are less interested in close relationships than others. This paper used data from a nationally representative sample of self-identified asexual participants (Analysis 1: nwomen = 216, nmen = 54, ngender diverse = 13; Analysis 2: nwomen = 53, nmen = 19, ngender diverse = 3) and matched samples of heterosexual and lesbian, gay, and bisexual/plurisexual (LGB) participants (N's = 75-283) drawn from the New Zealand Attitudes and Values Study (Ns = 19,396-54,183) to explore personality (Analysis 1) and approach and avoidance social motivations (Analysis 2). Compared to heterosexuals, asexual participants reported significantly lower extraversion, agreeableness, and conscientiousness, and higher emotionality, openness, and honesty-humility. Compared to those who identified as LGB, asexual participants reported significantly lower extraversion and agreeableness and higher honesty-humility. In addition, asexual participants scored significantly lower on approach (but not avoidance) social motivation than both heterosexual and LGB participants, indicating that they are less motivated to enhance positive experiences and behavior in their social relationships. These results help to clarify how personality and social motivations covary with sexual identity.


Assuntos
Extroversão Psicológica , Motivação , Feminino , Humanos , Masculino , Nova Zelândia , Personalidade , Comportamento Sexual
4.
Front Psychol ; 12: 694205, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34354638

RESUMO

Objective: This study explores a personality inventory derived from the results of an indigenous lexical study of personality. From the 272 most commonly used personality descriptors in Khoekhoegowab, the most-spoken of extant Khoesan click languages of southern Africa, an 11-factor model of personality-trait structure was identified. Here, the Khoekhoegowab Personality Inventory (KPI) was created based on those results. Its psychometric properties, the convergent and divergent validity of its scales, and its incremental validity over Big Five and Six traits for predicting physical and mental health, religious practice and attitudes, and income are reported. Methods: Two to five key terms were selected for each of 10 KPI scales: Temperance, Prosocial Diligence, Gossip, Honesty/Morality, Temper, Implacability, Humility, Vanity, Resiliency vs. Agitation, and Courage vs. Fear. These 38 total items were administered to a large sample of adult speakers of Khoekhoegowab in Namibia (N = 632), together with five imported inventories translated into Khoekhoegowab: the 30-item Questionnaire Big Six (QB6), General Self-Reported Health, the Cascades Mental Health Assessment, the Satisfaction with Life Scale, the Duke Religion Index. The properties and intercorrelations of KPI subscales are explored, and their predictive ability for the other variables is compared to that of the QB6. Results: Due to the small number of items on each scale, poor internal consistency was anticipated, but the KPI scales' properties were somewhat better than those of the QB6. R-square change by the inventories as a whole, after accounting for age and gender, indicted that the KPI scales explained more variance than the QB6 scales in almost all criterion variables. Replication of established associations for Big Six traits was mixed: associations were largely as expected for Resiliency, Conscientiousness, and Honesty, but less so for Agreeableness and Extraversion. Conclusions: The KPI had some advantages over the QB6 in predicting physical and mental health. In particular, the four items of Resiliency vs. Agitation predicted lower scores on all physical and mental problem scales. Given psychological-care needs in Namibia, this might be used as a non-intrusive screener. Measurement challenges common to both surveys are discussed, possible solutions, and the utility of higher-order structures are discussed.

5.
Polit Q ; 92(1): 132-138, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33821038

RESUMO

This article looks at the financial performance and position of English professional football before Covid-19 and the impact that the pandemic has had on the industry. It analyses revenue streams in different divisions, the dependency that clubs have on them and how they have changed as a result of the pandemic. The article also reviews key costs for football clubs, the extent to which they can be reduced, different business models that operate, and possible funding sources for the sport from third parties and within the industry.

6.
Front Psychol ; 11: 1166, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32733303

RESUMO

In Taiwan, classroom lectures are gradually shifting from traditional to diverse digital learning environments through social network websites. Facebook is being used to provide a space for sharing and discussing learning materials and knowledge for teachers and students. In this paper, we focus on the effects of applying Big Six approaches to Facebook on students' learning performance and behavior in a project innovation and implementation course. The participants were 72 first-year students in a college located in north Taiwan. The experimental participants who took the course were divided into two classes: the experimental group and the control group. While the experimental group used Facebook combined with Big Six approaches, the control group used traditional classroom tools combined with Big Six approaches. The experimental results show that the learning performance and creativity development of students from the experimental group are enhanced after using Facebook with Big Six approaches indicating a great social interaction and discussion cycle. On the other hand, students from the control group were only guided by the teacher. Owing to the lack of interactions between the Internet and the social learning community, there is no obvious enhancement in students' learning performance and creativity. In addition, we found that the teacher practiced the tips for guiding experimental students to solve the encountered problem, and then the students replied to the classmate's questions.

7.
Food Res Int ; 125: 108504, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31554119

RESUMO

The market for specialty coffee is growing as consumer preferences for high quality coffee become more complex. Identifying the sources of heterogeneity in consumer preferences for specialty coffee is essential to optimizing producer marketing strategies to ensure they both fully capitalize on and satisfy consumer demand. One source of increasing interest is consumer personality profiles, specifically those categorized by the Big Six personality traits. We use the Midlife Development Inventory to investigate the effect of consumer personality traits on willingness to pay for coffee produced by farmer cooperatives. Results from a field experiment using a Becker-DeGroot-Marschak mechanism indicate that, on average, consumers are willing to pay a $1.31 premium for a cup of pour over coffee that was produced by a cooperative member farmer. Consumers exhibiting the extraversion and conscientiousness traits were, on average, willing to pay an even higher premium while those with higher levels of agency had a lower willingness to pay. Results further highlight that sociodemographic characteristics do not always drive consumer purchase decisions and, in the absence of significant sociodemographic influence, intrinsic consumer characteristics like personality traits can better explain preferences.


Assuntos
Café , Comportamento do Consumidor/estatística & dados numéricos , Personalidade/fisiologia , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
8.
J Food Prot ; 82(9): 1512-1523, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31414899

RESUMO

Having reliable methods for detecting Shiga toxin-producing Escherichia coli (STEC) in foods is an important food safety goal. The majority of STEC outbreaks have involved either the O157:H7 serotype or one of six non-O157 serogroups, O26, O45, O103, O111, O121, and O145, termed "The Big Six." We have compared detection by PCR of the Shiga toxin genes stx1a and stx2a from STEC bacteria isolated from unclarified apple juice by simple centrifugation with the use of an immunocapture technique to minimize contaminants (such as pectin and polyphenols that may copurify with DNA) that may interfere with DNA amplification efficiencies and limit sensitivity. An internal control for successful immunocapture, DNA extraction, and PCR amplification was generated by introducing the pmRaspberry plasmid into an stx null strain, yielding an E. coli O45 pmRaspberry derivative that can be added to food samples directly. Using serial dilutions of a representative Big Six STEC in apple juice, our immunocapture method resulted in a 50% probability of detection value of 3.34, 2.25, and 4.25 CFU for detection by multiplex real-time PCR, growth on solid agar, and multiplex endpoint PCR, respectively. The time to result was 6.5 h, 9.5 h, and 1.5 days for immunocapture of Big Six STECs and detection by multiplex real-time PCR, endpoint PCR, and growth on solid agar, respectively. A set of 52 Big Six STEC isolates and 30 non-Big Six STEC strains was used to establish the inclusivity and exclusivity of the method. Finally, the ability to detect Big Six STEC contamination reliably was confirmed at 4.5 and 45 CFU/25-mL portions of refrigerated apple juice.


Assuntos
Microbiologia de Alimentos , Sucos de Frutas e Vegetais , Malus , Reação em Cadeia da Polimerase em Tempo Real , Escherichia coli Shiga Toxigênica , Microbiologia de Alimentos/métodos , Sucos de Frutas e Vegetais/microbiologia , Escherichia coli Shiga Toxigênica/isolamento & purificação
9.
Mem. Inst. Invest. Cienc. Salud (Impr.) ; 17(2): 71-76, ago. 2019. tab, ilus
Artigo em Espanhol | LILACS, BDNPAR | ID: biblio-1008486

RESUMO

Los serogrupos O26, O45, O103, O104, O111, O121, O145 y O157 de STEC se relacionan con un elevado número de casos de SUH a nivel mundial, por lo que están incluidos dentro de las categorías de mayor riesgo para los humanos, según los criterios de autoridades alimentarias de Estados Unidos y Europa. El método convencional de identificación de antígenos O y H se realiza por aglutinación con antisueros de conejo. Este método además de ser muy costoso y laborioso, no se encuentra disponible en el país para empleo masivo. En este contexto, el objetivo de este estudio observacional descriptivo de corte transverso ha sido la estandarización de una técnica de PCR múltiple para la detección de estos 8 serogrupos, a fin de contar con un sistema de detección eficiente, sensible y con potencial de aplicación en la industria alimentaria. Se estandarizaron reacciones de PCR empleando como controles positivos cepas E. coli de referencia correspondientes a la totalidad de los serogrupos citados. Se obtuvieron productos de tamaños esperados para cada serogrupo, no se observaron amplificaciones cruzadas o falsos positivos. Esta técnica estandarizada podría representar una herramienta rápida y menos costosa que la técnica serológica, con la capacidad de ser aplicada a diferentes matrices, permitiendo la detección de estos serogrupos en aislados STEC de ganado en pie, fuentes de agua de consumo, alimentos e incluso en aislamientos clínicos asociados a enfermedades humanas(AU)


STEC serogroups O26, O45, O103, O104, O111, O121, O145, and O157, are related to a high number of cases of HUS worldwide, so they are included in the categories of greatest risk for humans, according to the food administration criteria of the United States and Europe. The conventional method of identifying antigens O and H is carried out by agglutination with rabbit antisera. This method is very expensive and laborious and is not available in the country for massive-scale use. In this context, the objective of this cross-sectional descriptive observational study has been the standardization of a multiplex PCR technique for the detection of these 8 serogroups, in order to have an efficient and sensitive detection system with the potential for application in the food industry. PCR reactions were standardized using as positive controls reference E. coli strains to correspond to all the mentioned serogroups. Products of expected sizes were obtained for each serogroup; no cross-amplification or false positives were observed. This standardized technique could represent a quick and less expensive tool than the serological technique, with the possibility to be applied to different kind of samples, allowing the detection of these serogroups in STEC isolates of live cattle, sources of drinking water, food and even in clinical isolates associated with human diseases(AU)


Assuntos
Escherichia coli Shiga Toxigênica/isolamento & purificação , Reação em Cadeia da Polimerase Multiplex , Estudos Transversais , Escherichia coli O157/isolamento & purificação , Escherichia coli O157/genética , Escherichia coli Shiga Toxigênica/genética , Escherichia coli O104/isolamento & purificação , Escherichia coli O104/genética
10.
Rev. argent. microbiol ; Rev. argent. microbiol;51(1): 32-38, mar. 2019. ilus
Artigo em Inglês | LILACS | ID: biblio-1003278

RESUMO

The objectives of this study were: (1) to estimate STEC frequency in hide and carcass samples taken from beef slaughterhouses supplying the domestic market in Argentina, (2) to establish the pheno-genotypic characteristics of STEC and non-toxigenic Escherichia coli of serogroups O26, O45, O103, O121, O111, O145 or O157 isolated from the analyzed samples and, (3) to study their clonal relatedness. Sixty hides and 60 carcasses were analyzed. At the screening step, 48% of hide and 80% of carcass samples tested positive for the stx gene by endpoint PCR. The STEC isolation rate was 5% for hides and 8% for carcasses. The isolation rate of STEC-positive for O26, O45, O103, O111, O145 or O157 serogroups was 0% for hides and 2% for carcasses. With the purpose of studying the clonal relatedness of isolates, macrorestriction fragment analysis by pulsed-field gel electrophoresis was performed. The results indicated cross-contamination between hides and between carcasses of animals in the same lot and, that the origin of carcass contamination was their own hide, or the hides of other animals in the same lot. The high detection rate at the screening step, especially in carcasses, and the evidence of cross-contamination show the need to apply additional in-plant intervention strategies aimed at preventing carcass contamination.


Los objetivos del presente estudio fueron tres: 1) estimar la frecuencia de Escherichia coli productor de toxina Shiga (STEC) en muestras de cuero y carcasa de bovinos en frigoríficos de consumo interno de Argentina; 2) realizar la caracterización feno-genotípica de las cepas STEC y de Escherichia coli no toxigénicas pertenecientes a los serogrupos O26, O45, 0103, O121, O145 u O157 aisladas a partir de las muestras analizadas; 3) establecer la relación clonal de ese conjunto de cepas. Se analizaron 60 cueros y 60 carcasas. En la etapa de tamizaje, el gen stx se detectó en el 48% de las muestras de cuero y en el 80% de las muestras de carcasa por una PCR de punto final. La frecuencia de recuperación de cepas STEC fue del 5% en cueros y del 8% en carcasas, y la de cepas STEC positivas para los serogrupos O26, O45, O103, O121, O111, O145 u O157 fue del 0% en los cueros y del 2% en las carcasas. La relación clonal de las cepas aisladas se investigó a través de electroforesis de campo pulsado y análisis de los patrones de macrorrestricción generados. Los resultados demostraron la existencia de contaminación cruzada entre cueros y carcasas de animales pertenecientes a un mismo lote, y también que el origen de la contaminación fue el propio cuero del animal o el cuero de otros animales pertenecientes al mismo lote. Los altos porcentajes de detección en la etapa de tamizaje, especialmente en carcasas, y la evidencia de contaminación cruzada ponen de manifiesto la necesidad de evaluar la implementación de estrategias de intervención tendientes a evitar la contaminación de carcasas.


Assuntos
Escherichia coli Shiga Toxigênica/genética , Escherichia coli Shiga Toxigênica/virologia , Técnicas de Genotipagem/métodos , Carne Vermelha/microbiologia , Argentina , Programas de Rastreamento/veterinária , Matadouros
11.
Rev Argent Microbiol ; 51(1): 32-38, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-29937134

RESUMO

The objectives of this study were: (1) to estimate STEC frequency in hide and carcass samples taken from beef slaughterhouses supplying the domestic market in Argentina, (2) to establish the pheno-genotypic characteristics of STEC and non-toxigenic Escherichia coli of serogroups O26, O45, O103, O121, O111, O145 or O157 isolated from the analyzed samples and, (3) to study their clonal relatedness. Sixty hides and 60 carcasses were analyzed. At the screening step, 48% of hide and 80% of carcass samples tested positive for the stx gene by endpoint PCR. The STEC isolation rate was 5% for hides and 8% for carcasses. The isolation rate of STEC-positive for O26, O45, O103, O111, O145 or O157 serogroups was 0% for hides and 2% for carcasses. With the purpose of studying the clonal relatedness of isolates, macrorestriction fragment analysis by pulsed-field gel electrophoresis was performed. The results indicated cross-contamination between hides and between carcasses of animals in the same lot and, that the origin of carcass contamination was their own hide, or the hides of other animals in the same lot. The high detection rate at the screening step, especially in carcasses, and the evidence of cross-contamination show the need to apply additional in-plant intervention strategies aimed at preventing carcass contamination.


Assuntos
Matadouros , Bovinos/microbiologia , Escherichia coli Shiga Toxigênica/genética , Escherichia coli Shiga Toxigênica/isolamento & purificação , Animais , Argentina , Genótipo
12.
Food Microbiol ; 75: 55-60, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30056963

RESUMO

Shiga toxin-producing Escherichia coli (STEC) is one of the main cause of foodborne disease worldwide, but isolation rates or characteristics of this bacteria from ground beef in Chile are unknown. The present study aimed to isolate and characterize non-O157 STEC from ground beef sold at retail in the city of Santiago, Chile. We analyzed 430 ground beef samples for the presence of STEC, and isolated the microorganism in 10% of samples (43/430). We obtained 56 isolates from the 43 positive samples; 55 of these (98.2%) fermented sorbitol. Most isolates (98.2%; 55/56) showed ß-glucoronidase activity, and only six (10.7%; 6/56) were resistant to tellurite. Among the virulence factors studied (stx1, stx2, eae, and hlyA), stx2 was the only virulence factor in 41% of the isolates (23/56), whereas 10.7% (6/56) of isolates carried a combination of three virulence factors (stx1 + stx2 + hlyA). None of the isolates carried the gene eae. Finally, isolates were neither serogroups O157 nor "big six". In conclusion, ground beef sold in Santiago, Chile is contaminated with STEC; however, further studies are required for understanding their virulence potential.


Assuntos
Carne Vermelha/microbiologia , Escherichia coli Shiga Toxigênica/isolamento & purificação , Animais , Bovinos , Chile , Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/metabolismo , Contaminação de Alimentos/análise , Carne Vermelha/economia , Escherichia coli Shiga Toxigênica/classificação , Escherichia coli Shiga Toxigênica/genética , Escherichia coli Shiga Toxigênica/metabolismo , Fatores de Virulência/genética , Fatores de Virulência/metabolismo
13.
Assessment ; 24(8): 1024-1036, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26988405

RESUMO

Recent developments in personality research led to the proposition of two alternative six-factor trait models, the HEXACO model and the Big Six model. However, given the lack of direct comparisons, it is unclear whether the HEXACO and Big Six factors are distinct or essentially equivalent, that is, whether corresponding inventories measure similar or distinct personality traits. Using Structural Equation Modeling (Study 1), we found substantial differences between the traits as measured via the HEXACO-60 and the 30-item Questionnaire Big Six (30QB6), particularly for Honesty-Humility and Honesty-Propriety (both model's critical difference to the Big Five approach). This distinction was further supported by Study 2, showing differential capabilities of the HEXACO-60 and the 30QB6 to account for several criteria representing the theoretical core of Honesty-Humility and/or Honesty-Propriety. Specifically, unlike the indicator of Honesty-Humility, the indicator of Honesty-Propriety showed low predictive power for some conceptually relevant criteria, suggesting a limited validity of the 30QB6.


Assuntos
Inventário de Personalidade/normas , Personalidade , Adolescente , Adulto , Emoções , Feminino , Alemanha , Humanos , Internet , Funções Verossimilhança , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Assunção de Riscos , Adulto Jovem
14.
Pers Soc Psychol Bull ; 42(7): 893-909, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-27229678

RESUMO

To elucidate temporal sequences among and between person and situation variables, this work examines cross-measurement spillovers between situation experiences S (on the Situational Eight DIAMONDS characteristics [Duty, Intellect, Adversity, Mating, pOsitivity, Negativity, Deception, Sociality]) and personality states P (on the Big Six HEXACO dimensions [Honesty/Humility, Emotionality, eXtraversion, Agreeableness, Conscientiousness, Openness to Experience]) in experience sampling data. Multi-level modeling of lagged data at tn -1 and non-lagged data at tn grants the opportunity to examine (a) the stability (P → P, S → S), (b) cross-sectional associations (S ↔ P), and (c) cross-lagged associations among and between situation experiences and personality states (S → P, P → S). Findings indicated that there were (a) moderate stability paths, (b) small to moderate cross-sectional paths, and (c) only very small cross-lagged paths (though the different situation characteristics and personality states showed differential tendencies toward no directionality, S → P or P → S unidirectionality, or bidirectionality). Findings are discussed in light of refining studies on dynamic person-situation transactions.


Assuntos
Personalidade , Comportamento Social , Adolescente , Adulto , Feminino , Humanos , Masculino , Modelos Psicológicos , Adulto Jovem
15.
Food Microbiol ; 48: 1-7, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25790984

RESUMO

High pressure processing (HPP) is a safe and effective technology for improving food safety. Non-O157:H7 Shiga Toxin-producing Escherichia coli (STEC) have been increasingly implicated in foodborne illness outbreaks and recalls, and the USDA Food Safety Inspection Service (FSIS) has designated them as adulterants in meat (e.g. ground beef). In this study we compared the inactivation of multi-isolate cocktails of E. coli O157:H7 versus the non-O157:H7 STEC "Big Six" (i.e. O26, O45, O103, O111, O121, and O145) in ground beef (83% lean) using HPP at refrigeration temperature (4-7 °C). A >5-log CFU/g inactivation of both the Big Six and O157:H7 cocktails were observed at 450 MPa for 15 min. In general, the Big Six cocktail was found more sensitive to pressure stress (p < 0.05). In contrast, HPP treatment at 250 MPa (30 min) inactivated only 2.3 log of the Big Six versus 1.0 log of O157:H7. HPP treatment at 350 MPa (30 min) inactivated 4.7 log of the Big Six vs. 3.2 log of O157:H7. Multiple-cycle HPP cycles (250 or 350 MPa, three 5 min treatments) did not result in a 5 log reduction of the non-O157:H7 or O157:H7 STEC. Our results indicate that HPP inactivation parameters which are effective for O157:H7 STEC can be used for the non-O157:H7 Big Six isolates in ground beef.


Assuntos
Manipulação de Alimentos/métodos , Carne/microbiologia , Escherichia coli Shiga Toxigênica/crescimento & desenvolvimento , Animais , Bovinos , Contagem de Colônia Microbiana , Contaminação de Alimentos/análise , Manipulação de Alimentos/instrumentação , Microbiologia de Alimentos , Viabilidade Microbiana
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