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1.
Food Microbiol ; 99: 103779, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-34119091

RESUMEN

Genomic diversity of Listeria monocytogenes isolates from the deboning and slicing areas of three dry-cured ham processing plants was analysed. L. monocytogenes was detected in 58 out of 491 samples from the environment and equipment surfaces, all from the deboning area, with differences in prevalence among facilities. The most frequent PCR-serogroup was IIa (74.1%) followed by IIb and IIc, and only one isolate was serogroup IVb. Twenty different pulsotypes and 11 sequence types (STs) grouped into 10 clonal complexes (CCs) were determined. ST121 (CC121) and ST9 (CC9) were the most abundant. Premature stop codons (PMSC6 and PMSC19) associated with attenuated virulence were found in the inlA sequence in 7 out of 12 selected strains. CC121 strains were strong biofilm formers and some harboured the transposon Tn6188, related with increased tolerance to quaternary ammonium compounds. L. monocytogenes clones considered hypovirulent resulted predominant in the deboning areas. The clonal structure and potential virulence of the isolates could help to establish adequate control measures and cleaning protocols for the comprehensive elimination of the pathogen in dry-cured ham processing environment.


Asunto(s)
Equipos y Suministros/microbiología , Variación Genética , Listeria monocytogenes/genética , Listeria monocytogenes/aislamiento & purificación , Productos de la Carne/microbiología , Animales , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Técnicas de Tipificación Bacteriana , Biopelículas , Contaminación de Equipos/estadística & datos numéricos , Manipulación de Alimentos/instrumentación , Microbiología de Alimentos/instrumentación , Genómica , Listeria monocytogenes/clasificación , Listeria monocytogenes/fisiología , Carne de Cerdo/microbiología , Porcinos
2.
Neurourol Urodyn ; 39(1): 190-196, 2020 01.
Artículo en Inglés | MEDLINE | ID: mdl-31578776

RESUMEN

OBJECTIVES: The objective of this study is to investigate a multicenter study to establish if differences exist in the levator ani muscle avulsion (LAM) rates between deliveries performed with Malmstrom's vacuum and the Kiwi vacuum. STUDY DESIGN: A prospective, multicenter observational study with 199 primiparous subjects was performed. All patients had undergone vaginal delivery by vacuum (Malmstrom's or Kiwi). Avulsion was defined as an abnormal insertion of LAM in the lower pubic branch in the multiplanar mode, as identified in the three central sections by transperineal 3/4D echography 6 months after delivery. The area of ​​the levator hiatus was measured in the plane of minimum dimensions at rest, during the Valsalva maneuver and during contraction. RESULTS: LAM avulsion occurred in 33.1% of cases in which Malmstrom's vacuum was used and in 29.4% of cases in which the Kiwi vacuum was used (the difference was not statistically significant), which resulted in a crude odds ratio (OR) of 0.977 (0.426, 2.241; P = .957) and an adjusted OR of 2.90 (0.691; 12.20; P = .146). Women in the Malmstrom's vacuum group had a larger LHA at rest 14.77 vs 12.64 cm2 ; P = .001) and at maximum contraction (13.41 vs 10.83 cm2 ; P < 0.001) in comparison with the Kiwi group, although the difference did not reach statistical significance under Valsalva maneuver (18.71 vs 17.21 cm2 ; P = .051).Differences between both groups were detected in the measurements of the hiatus area levator at rest (14.77 vs 12.64 cm2 ), during the Valsalva maneuver (18.71 vs 17.21 cm2 ) and during maximum contraction (13.41 vs 10.83 cm2 ). CONCLUSIONS: In the present study, Malmstrom's vacuum was not associated with a higher risk of LAM in comparison with Kiwi's Omnicup.


Asunto(s)
Extracción Obstétrica/efectos adversos , Complicaciones del Trabajo de Parto/diagnóstico por imagen , Diafragma Pélvico/diagnóstico por imagen , Adulto , Extracción Obstétrica/métodos , Femenino , Humanos , Diafragma Pélvico/lesiones , Embarazo , Estudios Prospectivos , Ultrasonografía , Vacio , Maniobra de Valsalva/fisiología
3.
Food Microbiol ; 92: 103581, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-32950165

RESUMEN

The majority of cases of listeriosis are associated with the consumption of contaminated food. Some strains of Listeria monocytogenes can persist over months or years in meat processing plants increasing the risk of product contamination. The presence of L. monocytogenes was examined in 10 dry-cured ham processing facilities. A total of 1801 samples were collected from environment and equipment, during processing (1095) and after cleaning and disinfection (706). These samples were taken from non-food contact (736) and food contact (1065) surfaces. In addition, 204 samples from ham surfaces were also analysed. Prevalence varied from 6% to 34% among facilities, and was higher during processing than after cleaning and disinfection (24.8% vs 11.0%) and from non-food than from food contact surfaces (22.6% vs 17.4%). L. monocytogenes serotype 1/2a was predominant (53.9%), followed by 1/2c (26.0%) and 1/2b (15.3%) and less frequently 4b (4.8%). A total of 142 different pulsotypes were registered. Potential persistent L.monocytogenes strains were isolated in 9 out the 10 facilities, with no more than 6 pulsotypes in a given plant. Two pulsotypes were common in different installations, detected before and after cleaning and disinfection, highlighting the importance of monitoring the presence of this pathogen in dry-cured ham processing environments.


Asunto(s)
Manipulación de Alimentos/instrumentación , Listeria monocytogenes/aislamiento & purificación , Productos de la Carne/microbiología , Animales , Contaminación de Equipos , Contaminación de Alimentos/análisis , Microbiología de Alimentos , Listeria monocytogenes/clasificación , Listeria monocytogenes/genética , Productos de la Carne/análisis , Carne de Cerdo/análisis , Carne de Cerdo/microbiología , Porcinos
4.
Acta Obstet Gynecol Scand ; 98(11): 1413-1419, 2019 11.
Artículo en Inglés | MEDLINE | ID: mdl-31243757

RESUMEN

INTRODUCTION: Forceps use is the main risk factor for levator ani muscle (LAM) injuries. We believe that the disengagement of the forceps branches before delivery of the fetal head could influence LAM injuries, so we aimed to determine the influence of the disengagement of the forceps on the occurrence of LAM avulsion during forceps delivery. MATERIAL AND METHODS: A prospective, observational, multicenter study was conducted with 261 women who underwent forceps delivery. The women were classified according to whether the branches of the forceps had been disengaged before delivery of the fetal head. LAM avulsion was defined using a multislice mode (3 central slices). RESULTS: In all, 255 women completed the study (160 without disengagement and 95 with disengagement). LAM avulsions were observed in 37.9% of women in the group with disengagement and in 41.9% of women in the group without disengagement. The crude OR (without disengagement vs with disengagement) for avulsion was 0.90 (95% CI 0.49-1.67, P = 0.757) and an adjusted OR of 0.82 (95% CI 0.40-1.69, P = 0.603). CONCLUSIONS: We did not observe a statistically significant reduction in the LAM avulsion rate with disengagement of the forceps branches before delivery of the fetal head.


Asunto(s)
Canal Anal/lesiones , Extracción Obstétrica/efectos adversos , Complicaciones del Trabajo de Parto/diagnóstico , Forceps Obstétrico/efectos adversos , Complicaciones del Embarazo/cirugía , Resultado del Embarazo , Parto Obstétrico/efectos adversos , Parto Obstétrico/métodos , Extracción Obstétrica/métodos , Femenino , Estudios de Seguimiento , Humanos , Modelos Logísticos , Masculino , Edad Materna , Método de Montecarlo , Complicaciones del Trabajo de Parto/epidemiología , Oportunidad Relativa , Embarazo , Complicaciones del Embarazo/diagnóstico por imagen , Estudios Prospectivos , Medición de Riesgo , Resultado del Tratamiento , Estados Unidos
5.
Int J Food Sci Nutr ; 69(3): 334-343, 2018 May.
Artículo en Inglés | MEDLINE | ID: mdl-28728453

RESUMEN

Phytoestrogens are plant-derived polyphenols with structural and functional similarities to mammalian oestrogens. The aim of this work was to study the metabolism of phytoestrogens by children's intestinal microbiota and to compare it with previous results in adults. Faecal samples of 24 healthy children were subjected to phytoestrogen fermentation assay. Only one child produced equol, while O-desmethylangolensin was found in all. Urolithin production was detected in 14 children and enterolactone in 10. Further comparison with the metabolism of phytoestrogens by adult intestinal microbiota reflected that glycitein, dihydrogenistein, urolithins D and E, enterolactone, secoisolariciresinol and arctigenin were the most important metabolites differentiating between adult and child microbial gut metabolism. Although the child intestinal microbiota showed the ability to metabolise isoflavones, ellagitannins and lignans to a certain extent, it generally showed a reduced metabolism of phytoestrogens, with a lack of 5-hydroxy equol and enterodiol, and less urolithins and enterolactone producers.


Asunto(s)
Microbioma Gastrointestinal , Fitoestrógenos/metabolismo , 4-Butirolactona/análogos & derivados , 4-Butirolactona/metabolismo , Adulto , Butileno Glicoles/metabolismo , Estudios de Casos y Controles , Preescolar , Cumarinas/metabolismo , Equol/metabolismo , Heces/microbiología , Femenino , Furanos/metabolismo , Humanos , Taninos Hidrolizables/metabolismo , Lactante , Isoflavonas/metabolismo , Lignanos/metabolismo , Masculino , Polifenoles/metabolismo
6.
J Dairy Sci ; 100(1): 113-117, 2017 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-27837972

RESUMEN

Many food safety-related studies require the tracking of inoculated food-borne pathogens to monitor their fate in food complex environments. In the current study, we demonstrate the potential of plasmids containing the fluorescence protein gene evoglow-Pp1 (Evocatal, Dusseldorf, Germany) as a real-time reporter system for Listeria strains. This anaerobic fluorescent protein provides an easily detectable phenotype of microorganisms for food safety studies. This work is the first to report a reliable method to identify fluorescently labeled Listeria strains in food ecosystems.


Asunto(s)
Microbiología de Alimentos/métodos , Listeria monocytogenes/genética , Listeria/genética , Proteínas Luminiscentes/análisis , Listeria monocytogenes/aislamiento & purificación , Plásmidos/genética
7.
J Food Sci Technol ; 54(5): 1346-1349, 2017 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-28416886

RESUMEN

Cheeses manufactured from pasteurized milk supplemented with glycerol and reuterin-producing Lactobacillus reuteri INIA P572 as adjunct to the commercial starter culture were analysed in order to optimize a biopreservation strategy. The highest reuterin concentration determined by a colorimetric assay was detected on day 1 in cheeses with 100-500 mM glycerol. The presence of reuterin was confirmed by a direct detection technique as HPLC. Cheeses made with L. reuteri and 200 or 500 mM glycerol showed a red tendency in color in comparison with control. The results with purified reuterin suggested that the development of slightly rosy colour in cheese was related to some compound produced/overproduced when higher levels of glycerol were present in cheese, but not due to reuterin. Application of L. reuteri INIA P572 as adjunct to the commercial starter with 100 mM glycerol led to such a reuterin concentration in cheese that could control undesirable microorganisms, avoiding the presence of color-changing compounds.

8.
Appl Microbiol Biotechnol ; 100(17): 7665-77, 2016 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-27216614

RESUMEN

In this work, a variety of biochemical properties of Enterococcus faecium CECT 8849, which had been isolated from breast milk, were analyzed. Its acidifying capacity and proteolytic activity were low but, in contrast, remarkable peptidase and esterase activities were observed. Ethanol and 3-hydroxy-2-butanone were the most abundant volatile compounds found in experimental model cheese manufactured with E. faecium CECT 8849. This strain inhibited the growth of several Listeria monocytogenes and Listeria innocua strains in vitro. Enterocin A and B structural genes were detected in E. faecium CECT 8849. Model fermented milk and cheeses were manufactured from milk inoculated or not with L. innocua CECT 8848 (2.5-3 log10 colony forming units mL(-1)) using E. faecium CECT 8849 or Lactococcus lactis ESI 153 as starter cultures. Although E. faecium CECT 8849 controlled Listeria growth in both dairy models, it led to lower reduction in Listeria counts when compared with L. lactis ESI 153.


Asunto(s)
Queso/microbiología , Productos Lácteos Cultivados/microbiología , Enterococcus faecium/enzimología , Enterococcus faecium/metabolismo , Esterasas/metabolismo , Péptido Hidrolasas/metabolismo , Compuestos Orgánicos Volátiles/análisis , Acetoína/metabolismo , Bacteriocinas/genética , Industria Lechera , Enterococcus faecium/genética , Enterococcus faecium/aislamiento & purificación , Etanol/análisis , Microbiología de Alimentos , Humanos , Lactococcus lactis/metabolismo , Listeria monocytogenes/crecimiento & desarrollo , Leche Humana/microbiología
9.
Lipids Health Dis ; 15: 78, 2016 Apr 18.
Artículo en Inglés | MEDLINE | ID: mdl-27090218

RESUMEN

BACKGROUND: Nutrition therapy is the cornerstone of treating diabetes mellitus. The inclusion of fish (particularly oily fish) at least two times per week is recommended by current international dietary guidelines for type 2 diabetes. In contrast to a large number of human studies examining the effects of oily fish on different cardiovascular risk factors, little research on this topic is available in patients with type 2 diabetes. The aims of this pilot study were to investigate the effects of a sardine-enriched diet on metabolic control, adiponectin, inflammatory markers, erythrocyte membrane fatty acid (EMFA) composition, and gut microbiota in drug-naïve patients with type 2 diabetes. METHODS: 35 drug-naïve patients with type 2 diabetes were randomized to follow either a type 2 diabetes standard diet (control group: CG), or a standard diet enriched with 100 g of sardines 5 days a week (sardine group: SG) for 6 months. Anthropometric, dietary information, fasting glycated hemoglobin, glucose, insulin, adiponectin, inflammatory markers, EMFA and specific bacterial strains were determined before and after intervention. RESULTS: There were no significant differences in glycemic control between groups at the end of the study. Both groups decreased plasma insulin (SG: -35.3%, P = 0.01, CG: -22.6%, P = 0.02) and homeostasis model of assessment--insulin resistance (HOMA-IR) (SG: -39.2%, P = 0.007, CG: -21.8%, P = 0.04) at 6-months from baseline. However only SG increased adiponectin in plasma compared to baseline level (+40.7%, P = 0.04). The omega-3 index increased 2.6% in the SG compared to 0.6% in the CG (P = 0.001). Both dietary interventions decreased phylum Firmicutes (SG and CG: P = 0.04) and increased E. coli concentrations (SG: P = 0.01, CG: P = 0.03) at the end of the study from baseline, whereas SG decreased Firmicutes/Bacteroidetes ratio (P = 0.04) and increased Bacteroides-Prevotella (P = 0.004) compared to baseline. CONCLUSIONS: Although enriching diet with 100 g of sardines 5 days a week during 6 months to a type 2 diabetes standard diet seems to have neutral effects on glycemic control in drug-naïve patients with type 2 diabetes, this nutritional intervention could have beneficial effects on cardiovascular risk. Furthermore, both dietary interventions decreased HOMA-IR and altered gut microbiota composition of drug-naïve patients with type 2 diabetes. TRIAL REGISTRATION: Trial number and name of the registry: NCT02294526, ClinicalTrials.gov.


Asunto(s)
Diabetes Mellitus Tipo 2/dietoterapia , Diabetes Mellitus Tipo 2/microbiología , Peces , Microbioma Gastrointestinal , Adiponectina/sangre , Animales , Biomarcadores/sangre , Composición Corporal/efectos de los fármacos , Membrana Eritrocítica/química , Membrana Eritrocítica/efectos de los fármacos , Ácidos Grasos/análisis , Ácidos Grasos/sangre , Ácidos Grasos Omega-3/sangre , Femenino , Productos Pesqueros , Humanos , Inflamación/sangre , Masculino , Persona de Mediana Edad , Proyectos Piloto
10.
Int J Food Sci Nutr ; 67(2): 117-24, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-26878882

RESUMEN

Almost all soy isoflavones exist as glycosides, daidzin, genistin, and glycitin. We analyzed the capacity of 92 strains of lactic acid bacteria (LAB) and bifidobacteria with biotechnological interest to process the glycosylated isoflavones daidzin, genistin, and glycitin in their more bioavailable aglycones and their metabolites as dihydrodaidzein (DHD), O-desmethylangolensin, and equol. Representative strains of the four genera studied Lactobacillus, Enterococcus, Lactococcus, and Bifidobacterium were able to produce daidzein, genistein, and glycitein, with the exception of the lactobacilli, which did not produced glycitein in soy extracts. The production of the aglycone isoflavones could be correlated with the ß-glucosidase activity of the strains. The isoflavone metabolism is limited to the glycoside hydrolysis in the most of these strains. Moreover, Enterococcus faecalis INIA P333 and Lactobacillus rhamnosus INIA P540 were able to transform daidzein in DHD. LAB and bifidobacteria studied in the present work have a great potential in the metabolism of isoflavones and could be selected for the development of functional fermented soy foods.


Asunto(s)
Bifidobacterium/metabolismo , Isoflavonas/metabolismo , Lactobacillus/metabolismo , Isoflavonas/química , Estructura Molecular
11.
Molecules ; 21(8)2016 Aug 09.
Artículo en Inglés | MEDLINE | ID: mdl-27517891

RESUMEN

Phytoestrogens are plant-derived polyphenols with a structure similar to human estrogens. The three main groups of phytoestrogens, isoflavones, ellagitannins, and lignans, are transformed into equol, urolithins, and enterolignans, respectively, by bacteria. These metabolites have more estrogenic/antiestrogenic and antioxidant activities than their precursors, and they are more bioavailable. The aim of this study was to analyze the metabolism of isoflavones, lignans and ellagitannins by gut microbiota, and to study the possible correlation in the metabolism of these three groups of phytoestrogens. In vitro fermentation experiments were performed with feces samples from 14 healthy adult volunteers, and metabolite formation was measured by HPLC-PAD and HPLC-ESI/MS. Only the microbiota of one subject produced equol, while most of them showed production of O-desmethylangolensin (O-DMA). Significant inter-subject differences were observed in the metabolism of dihydrodaidzein and dihydrogenistein, while the glucoside isoflavones and their aglycones showed less variability, except for glycitin. Most subjects produced urolithins M-5 and E. Urolithin D was not detected, while uroltithin B was found in half of the individuals analyzed, and urolithins A and C were detected in two and four subjects, respectively. Enterolactone was found in all subjects, while enterodiol only appeared in five. Isoflavone metabolism could be correlated with the metabolism of lignans and ellagitannins. However, the metabolism of ellagitannins and lignans could not be correlated. This the first study where the metabolism of the three groups together of phytoestrogen, isoflavones, lignans, and ellagitannins by gut microbiota is analyzed.


Asunto(s)
Cumarinas/metabolismo , Microbioma Gastrointestinal/fisiología , Taninos Hidrolizables/metabolismo , Isoflavonas/metabolismo , Lignanos/metabolismo , Fitoestrógenos/metabolismo , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad
12.
J Sci Food Agric ; 96(7): 2573-8, 2016 May.
Artículo en Inglés | MEDLINE | ID: mdl-26268416

RESUMEN

BACKGROUND: High hydrostatic pressure (HHP) combined with reuterin and lactoperoxidase system (LPS) has exerted antimicrobial activity against Listeria monocytogenes in cold-smoked salmon at chilled temperatures. Therefore the purpose of this work was to evaluate the effect of HHP combined with reuterin, LPS and lactoferrin (LF) on the survival of Salmonella enterica subsp. enterica serovar Enteritidis and Escherichia coli O157:H7 in cold-smoked salmon stored at 4 and 10 °C. RESULTS: Salmonella Enteritidis and E. coli O157:H7 were reduced more than 3 log colony-forming units (CFU) g(-1) by the pressure treatment (450 MPa/5 min). LPS slightly diminished pathogen levels throughout storage, whereas no effect was recorded when reuterin or LF was added. The Salmonella population was below the detection limit (<1 log CFU g(-1) ) during the storage of HHP-treated smoked salmon at 4 and 10 °C. The antimicrobial activity of HHP against E. coli O157:H7 was increased when 450 MPa was applied in combination with LPS in cold-smoked salmon at 4 and 10 °C. CONCLUSION: HHP at 450 MPa/5 min inactivated S. Enteritidis in cold-smoked salmon and in combination with LPS would be useful as a hurdle technology approach against E. coli O157:H7, even under mild temperature abuse conditions. © 2015 Society of Chemical Industry.


Asunto(s)
Antiinfecciosos/farmacología , Escherichia coli O157/efectos de los fármacos , Manipulación de Alimentos/métodos , Microbiología de Alimentos , Carne/microbiología , Salmonella enteritidis/efectos de los fármacos , Animales , Conservación de Alimentos , Presión , Salmón/microbiología
13.
World J Microbiol Biotechnol ; 32(7): 119, 2016 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-27263014

RESUMEN

In the last two decades, there has been increasing evidence supporting the role of the intestinal microbiota in health and disease, as well as the use of probiotics to modulate its activity and composition. Probiotic bacteria selected for commercial use in foods, mostly lactic acid bacteria and bifidobacteria, must survive in sufficient numbers during the manufacturing process, storage, and passage through the gastro-intestinal tract. They have several modes of action and it is crucial to unravel the mechanisms underlying their postulated beneficial effects. To track their survival and persistence, and to analyse their interaction with the gastro-intestinal epithelia it is essential to discriminate probiotic strains from endogenous microbiota. Fluorescent reporter proteins are relevant tools that can be exploited as a non-invasive marker system for in vivo real-time imaging in complex ecosystems as well as in vitro fluorescence labelling. Oxygen is required for many of these reporter proteins to fluoresce, which is a major drawback in anoxic environments. However, some new fluorescent proteins are able to overcome the potential problems caused by oxygen limitations. The current available approaches and the benefits/disadvantages of using reporter vectors containing fluorescent proteins for labelling of bacterial probiotic species commonly used in food are addressed.


Asunto(s)
Bifidobacterium/química , Proteínas Fluorescentes Verdes/análisis , Ácido Láctico/análisis , Probióticos/análisis , Anaerobiosis , Animales , Bifidobacterium/genética , Bifidobacterium/aislamiento & purificación , Bifidobacterium/metabolismo , Proteínas Fluorescentes Verdes/genética , Proteínas Fluorescentes Verdes/metabolismo , Humanos , Ácido Láctico/metabolismo , Interacciones Microbianas , Microbiota , Imagen Óptica
14.
PLoS Pathog ; 9(1): e1003141, 2013 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-23358328

RESUMEN

Adherent-invasive Escherichia coli (AIEC) are abnormally predominant on Crohn's disease (CD) ileal mucosa. AIEC reference strain LF82 adheres to ileal enterocytes via the common type 1 pili adhesin FimH and recognizes CEACAM6 receptors abnormally expressed on CD ileal epithelial cells. The fimH genes of 45 AIEC and 47 non-AIEC strains were sequenced. The phylogenetic tree based on fimH DNA sequences indicated that AIEC strains predominantly express FimH with amino acid mutations of a recent evolutionary origin - a typical signature of pathoadaptive changes of bacterial pathogens. Point mutations in FimH, some of a unique AIEC-associated nature, confer AIEC bacteria a significantly higher ability to adhere to CEACAM-expressing T84 intestinal epithelial cells. Moreover, in the LF82 strain, the replacement of fimH(LF82) (expressing FimH with an AIEC-associated mutation) with fimH(K12) (expressing FimH of commensal E. coli K12) decreased the ability of bacteria to persist and to induce severe colitis and gut inflammation in infected CEABAC10 transgenic mice expressing human CEACAM receptors. Our results highlight a mechanism of AIEC virulence evolution that involves selection of amino acid mutations in the common bacterial traits, such as FimH protein, and leads to the development of chronic inflammatory bowel disease (IBD) in a genetically susceptible host. The analysis of fimH SNPs may be a useful method to predict the potential virulence of E. coli isolated from IBD patients for diagnostic or epidemiological studies and to identify new strategies for therapeutic intervention to block the interaction between AIEC and gut mucosa in the early stages of IBD.


Asunto(s)
Adhesinas de Escherichia coli/genética , Enfermedad de Crohn/microbiología , Infecciones por Escherichia coli/microbiología , Escherichia coli/patogenicidad , Proteínas Fimbrias/genética , Mutación Puntual , Adhesinas de Escherichia coli/metabolismo , Animales , Antígenos CD/metabolismo , Adhesión Bacteriana , Moléculas de Adhesión Celular/metabolismo , Línea Celular Tumoral , Colitis/metabolismo , Colitis/patología , Enfermedad de Crohn/metabolismo , Enterocitos/metabolismo , Enterocitos/microbiología , Enterocitos/patología , Escherichia coli/genética , Escherichia coli/metabolismo , Infecciones por Escherichia coli/metabolismo , Proteínas Fimbrias/metabolismo , Proteínas Ligadas a GPI/metabolismo , Genes Bacterianos/genética , Humanos , Íleon/metabolismo , Íleon/microbiología , Íleon/patología , Mucosa Intestinal/metabolismo , Mucosa Intestinal/patología , Masculino , Ratones , Ratones Transgénicos , Factores de Virulencia
15.
Appl Environ Microbiol ; 81(21): 7582-92, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26296733

RESUMEN

Faecalibacterium prausnitzii depletion in intestinal diseases has been extensively reported, but little is known about intraspecies variability. This work aims to determine if subjects with gastrointestinal disease host mucosa-associated F. prausnitzii populations different from those hosted by healthy individuals. A new species-specific PCR-denaturing gradient gel electrophoresis (PCR-DGGE) method targeting the 16S rRNA gene was developed to fingerprint F. prausnitzii populations in biopsy specimens from 31 healthy control (H) subjects and 36 Crohn's disease (CD), 23 ulcerative colitis (UC), 6 irritable bowel syndrome (IBS), and 22 colorectal cancer (CRC) patients. The richness of F. prausnitzii subtypes was lower in inflammatory bowel disease (IBD) patients than in H subjects. The most prevalent operational taxonomic units (OTUs) consisted of four phylotypes (OTUs with a 99% 16S rRNA gene sequence similarity [OTU99]), which were shared by all groups of patients. Their distribution and the presence of some disease-specific F. prausnitzii phylotypes allowed us to differentiate the populations in IBD and CRC patients from that in H subjects. At the level of a minimum similarity of 97% (OTU97), two phylogroups accounted for 98% of the sequences. Phylogroup I was found in 87% of H subjects but in under 50% of IBD patients (P = 0.003). In contrast, phylogroup II was detected in >75% of IBD patients and in only 52% of H subjects (P = 0.005). This study reveals that even though the main members of the F. prausnitzii population are present in both H subjects and individuals with gut diseases, richness is reduced in the latter and an altered phylotype distribution exists between diseases. This approach may serve as a basis for addressing the suitability of F. prausnitzii phylotypes to be quantified as a putative biomarker of disease and depicting the importance of the loss of these subtypes in disease pathogenesis.


Asunto(s)
Clostridiales/clasificación , Clostridiales/aislamiento & purificación , Variación Genética , Genotipo , Enfermedades Inflamatorias del Intestino/microbiología , Mucosa Intestinal/microbiología , Biopsia , Clostridiales/genética , Análisis por Conglomerados , ADN Bacteriano/química , ADN Bacteriano/genética , ADN Ribosómico/química , ADN Ribosómico/genética , Electroforesis en Gel de Gradiente Desnaturalizante , Humanos , Datos de Secuencia Molecular , Filogenia , Reacción en Cadena de la Polimerasa , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN
16.
Appl Microbiol Biotechnol ; 99(16): 6865-77, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-26129953

RESUMEN

Lactic acid bacteria (LAB) are commonly used in the production of fermented and probiotic foods. Development of molecular tools to discriminate the strains of interest from the endogenous microbiota in complex environments like food or gut is of high interest. Green fluorescent protein (GFP)-like chromophores strictly requires molecular oxygen for maturation of fluorescence, which restrict the study of microorganisms in low-oxygen environments. In this work, we have developed a noninvasive cyan-green fluorescent based reporter system for real-time tracking of LAB that is functional under anoxic conditions. The evoglow-Pp1 was cloned downstream from the promoters D-alanyl-D-alanine carboxypeptidase and elongation factor Tu of Lactobacillus reuteri CECT925 using pNZ8048 and downstream of the lactococcal P1 promoter using pT1NX. The classical gfp was also cloned in pT1NX. These recombinant expression vectors were electroporated into Lactococccus, Lactobacillus, and Enterococcus strains with biotechnological and/or probiotic interests to assess and compare their functionality under different conditions of oxygen and pH. The expression was analyzed by imaging and fluorometric methods as well as by flow cytometry. We demonstrate that reporter systems pNZ:TuR-aFP and pT1-aFP are two versatile molecular markers for monitoring LAB in food and fecal environments without the potential problems caused by oxygen and pH limitations, which could be exploited for in vivo studies. Production of the fluorescent protein did not disturb any important physiological properties of the parental strains, such as growth rate, reuterin, or bacteriocin production.


Asunto(s)
Enterococcus/genética , Genes Reporteros , Proteínas Fluorescentes Verdes/análisis , Lactobacillus/genética , Lactococcus/genética , Anaerobiosis , Clonación Molecular , Electroporación , Citometría de Flujo , Fluorometría , Expresión Génica , Proteínas Fluorescentes Verdes/genética , Concentración de Iones de Hidrógeno , Imagen Óptica , Plásmidos , Regiones Promotoras Genéticas , Transformación Bacteriana
17.
Gut ; 63(1): 116-24, 2014 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-23598352

RESUMEN

OBJECTIVE: Western diet is a risk factor for Crohn's disease (CD). Carcinoembryonic antigen-related cell adhesion molecule 6 (CEACAM6) is abnormally expressed in CD patients. This allows adherent-invasive Escherichia coli (AIEC) to colonise the gut mucosa and leads to inflammation. We assessed the effects of a high fat/high sugar (HF/HS) Western diet on gut microbiota composition, barrier integrity and susceptibility to infection in transgenic CEABAC10 mice expressing human CEACAMs. DESIGN: Colonic microbiota composition and susceptibility of CEABAC10 mice to AIEC LF82 bacteria infection were determined in mice fed a conventional or HF/HS diet. Barrier function and inflammatory response were assessed by studying intestinal permeability, tight junction protein and mucin expression and localisation, and by determining histological score and levels of cytokine release. RESULTS: HF/HS diet led to dysbiosis in WT and transgenic CEABAC10 mice, with a particular increase in E coli population in HF/HS-fed CEABAC10 mice. These mice showed decreased mucus layer thickness, increased intestinal permeability, induction of Nod2 and Tlr5 gene transcription, and increased TNFα secretion. These modifications led to a higher ability of AIEC bacteria to colonise the gut mucosa and to induce inflammation. CONCLUSIONS: Western diet induces changes in gut microbiota composition, alters host homeostasis and promotes AIEC gut colonisation in genetically susceptible mice. These results support the multifactorial aetiology of CD and highlight the importance of diet in CD pathogenesis.


Asunto(s)
Colon/microbiología , Dieta Alta en Grasa/efectos adversos , Sacarosa en la Dieta/efectos adversos , Disbiosis/etiología , Escherichia coli/fisiología , Interacciones Huésped-Patógeno , Mucosa Intestinal/microbiología , Animales , Biomarcadores/metabolismo , Moléculas de Adhesión Celular/genética , Moléculas de Adhesión Celular/metabolismo , Colon/metabolismo , Colon/patología , Enfermedad de Crohn/etiología , Citocinas/metabolismo , Disbiosis/metabolismo , Disbiosis/microbiología , Disbiosis/patología , Infecciones por Escherichia coli/etiología , Femenino , Predisposición Genética a la Enfermedad , Homeostasis , Mucosa Intestinal/metabolismo , Mucosa Intestinal/patología , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos , Microbiota
18.
Int J Med Microbiol ; 304(3-4): 464-75, 2014 May.
Artículo en Inglés | MEDLINE | ID: mdl-24713205

RESUMEN

BACKGROUND: Crohn's disease (CD) and ulcerative colitis (UC) diagnosis requires comprehensive examination of the patient. Faecalibacterium prausnitzii and Escherichia coli have been reported as representatives of Inflammatory Bowel Disease (IBD) dysbiosis. The aim was to determine whether or not quantification of these species can be used as a complementary tool either for diagnostic or prognostic purposes. METHODS: Mucosa-associated F. prausnitzii and E. coli abundance was determined in 28 controls (H), 45 CD, 28 UC patients and 10 irritable bowel syndrome (IBS) subjects by quantitative polymerase chain reaction (qPCR) and the F. prausnitzii-E. coli index (F-E index) was calculated. Species abundances were normalized to total bacteria and human cells. Data was analyzed taking into account patients' phenotype and most relevant clinical characteristics. RESULTS: IBD patients had lower F. prausnitzii abundance than H and IBS (P<0.001). CD patients showed higher E. coli counts than H and UC patients (P<0.001). The F-E index discriminated between H, CD and UC patients, and even between disease phenotypes that are usually difficult to distinguish as ileal-CD (I-CD) from ileocolonic-CD and colonic-CD from extensive colitis. E. coli increased in active CD patients, and remission in I-CD patients was compromised by high abundance of this species. Treatment with anti-tumor necrosis factor (TNF) α diminished E. coli abundance in I-CD whereas none of the treatments counterbalanced F. prausnitzii depletion. CONCLUSION: F. prausnitzii and E. coli are useful indicators to assist in IBD phenotype classification. The abundance of these species could also be used as a supporting prognostic tool in I-CD patients. Our data indicates that current medication does not restore the levels of these two species to those found in a healthy gut.


Asunto(s)
Carga Bacteriana , Escherichia coli/aislamiento & purificación , Bacterias Grampositivas/aislamiento & purificación , Enfermedades Inflamatorias del Intestino/microbiología , Mucosa Intestinal/microbiología , Síndrome del Colon Irritable/microbiología , Adolescente , Adulto , Estudios de Cohortes , Femenino , Humanos , Enfermedades Inflamatorias del Intestino/diagnóstico , Síndrome del Colon Irritable/diagnóstico , Masculino , Persona de Mediana Edad , Reacción en Cadena en Tiempo Real de la Polimerasa , Adulto Joven
19.
Food Microbiol ; 41: 27-32, 2014 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-24750810

RESUMEN

The effect of high hydrostatic pressure (HHP) treatments in combination with the lactoperoxidase system (LPOS) or activated lactoferrin (ALF) on Listeria monocytogenes, Salmonella enterica subsp. enterica serovar Enteritidis and Escherichia coli O157:H7 was investigated in cured beef carpaccio stored at 8 °C or 22 °C during 7 d. HHP (450 MPa for 5 min) reduced pathogen levels by 1-3 log units and the antimicrobial effect remained during 7 d of storage under temperature abuse conditions at 8 °C and at 22 °C. The individual application of LPOS and ALF did not affect the survival of the three pathogens studied during storage. However, a synergistic bactericidal interaction between LPOS and HHP was observed against S. Enteritidis and E. coli O157:H7. Combined treatments of HHP with LPOS would be useful to reduce the intensity of pressurization treatments diminishing changes in the quality of meat products.


Asunto(s)
Escherichia coli/crecimiento & desarrollo , Conservación de Alimentos/métodos , Listeria monocytogenes/crecimiento & desarrollo , Productos de la Carne/microbiología , Salmonella enteritidis/crecimiento & desarrollo , Animales , Bovinos , Recuento de Colonia Microbiana , Escherichia coli/química , Conservantes de Alimentos/química , Almacenamiento de Alimentos , Presión Hidrostática , Lactoferrina/química , Lactoperoxidasa/química , Listeria monocytogenes/química , Productos de la Carne/análisis , Viabilidad Microbiana , Salmonella enteritidis/química
20.
Microorganisms ; 12(6)2024 Jun 06.
Artículo en Inglés | MEDLINE | ID: mdl-38930540

RESUMEN

Pathobionts have been implicated in various chronic diseases, including Crohn's disease (CD), a multifactorial chronic inflammatory condition that primarily affects the gastrointestinal tract, causing inflammation and damage to the digestive system. While the exact cause of CD remains unclear, adherent-invasive Escherichia coli (AIEC) strains have emerged as key contributors to its pathogenesis. AIEC are characterized by their ability to adhere to and invade intestinal epithelial cells and survive and replicate inside macrophages. However, the mechanisms underlying the virulence and persistence of AIEC within their host remain the subject of intensive research. Toxin-antitoxin systems (TAs) play a potential role in AIEC pathogenesis and may be therapeutic targets. These systems generally consist of two components: a toxin harmful to the cell and an antitoxin that neutralizes the toxin's effects. They contribute to bacterial survival in adverse conditions and regulate bacterial growth and behavior, affecting various cellular processes in bacterial pathogens. This review focuses on the current information available to determine the roles of TAs in the pathogenicity of AIEC. Their contribution to the AIEC stress response, biofilm formation, phage inhibition, the maintenance of mobile genetic elements, and host lifestyles is discussed.

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