Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 26
Filtrar
Más filtros

Tipo del documento
Intervalo de año de publicación
1.
J Neurovirol ; 27(6): 960-965, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-34739714

RESUMEN

We present the case of a patient in the third decade of life, with asthma as comorbidity, who presented to the emergency department due to odynophagia, dyspnea, and cough of 2 days of evolution, later developing acute ventilatory failure requiring orotracheal intubation. The high-resolution chest tomography study showed consolidation due to a pneumonic process towards the posterior segment of the right lower lobe with areas of ground-glass infiltrates with a peripheral distribution. During the clinical course, the patient presented multiple seizure episodes that met the criteria for status epilepticus with MRI compatible with changes due to leptomeningitis. Given symptoms and thorax imaging, tests for SARS-CoV-2 ensued, with both positive RT-PCR in bronchoalveolar lavage and cerebrospinal fluid for the virus also positive. RT-PCR multiplex panel of meningitis/encephalitis results negative for 14 common organisms. A diagnosis of acute meningoencephalitis associated with COVID-19 was considered, with an adequate response to corticosteroid management; to our knowledge, this is the first adult patient with CNS involvement and CSF positive test in Latin America.


Asunto(s)
COVID-19 , Meningoencefalitis , Adulto , COVID-19/complicaciones , Colombia , Humanos , Meningoencefalitis/diagnóstico , Meningoencefalitis/diagnóstico por imagen , SARS-CoV-2 , Convulsiones
2.
J Sci Food Agric ; 99(4): 1548-1553, 2019 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-30144058

RESUMEN

BACKGROUND: Establishing novel preharvest intervention strategies for leafy green growers is of critical need with the rise in foodborne outbreaks associated with these products. Recent studies have shown that lactic acid bacteria (LAB) are able to reduce the presence of Escherichia coli O157:H7 in various food matrices. Electrostatic application of organic acids has been shown to be effective as a postharvest safety intervention to reduce E.coli O157:H7 on leafy greens. The effect of LAB electrostatically applied and sprinkler irrigated once over a 4 week growth cycle was evaluated against E. coli O157:H7 on spinach. RESULTS: The results indicated that E. coli O157:H7 when applied once during the 4 week growth cycle will survive in the soil and spinach leaves at harvest. LAB applied electrostatically and by sprinkler irrigation water on the soil and/or leaf surface within the first 4 weeks of the growing cycle resulted in a significant reduction (almost a 3 log10 reduction) of E. coli O157:H7 both on the leaf and in the soil at harvest, regardless of the application time (P < 0.01). CONCLUSION: LAB surface treatments have the potential to improve the safety of leafy green plants as a preharvest food safety intervention when combined with good agricultural practices. © 2018 Society of Chemical Industry.


Asunto(s)
Antibiosis , Escherichia coli O157/crecimiento & desarrollo , Lactobacillales/fisiología , Spinacia oleracea/microbiología , Recuento de Colonia Microbiana , Escherichia coli O157/fisiología , Contaminación de Alimentos/prevención & control , Lactobacillales/crecimiento & desarrollo , Viabilidad Microbiana , Hojas de la Planta/crecimiento & desarrollo , Hojas de la Planta/microbiología , Spinacia oleracea/crecimiento & desarrollo
3.
Appl Environ Microbiol ; 79(15): 4744-50, 2013 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-23793628

RESUMEN

Lymph nodes (mandibular, mesenteric, mediastinal, and subiliac; n = 68) and fecal (n = 68) and hide (n = 35) samples were collected from beef carcasses harvested in an abattoir in Mexico. Samples were analyzed for Salmonella, and presumptive colonies were subjected to latex agglutination. Of the isolates recovered, a subset of 91 was characterized by serotyping, pulsed-field gel electrophoresis (PFGE), and antimicrobial susceptibility phenotyping. Salmonella was isolated from 100% (hide), 94.1% (feces), 91.2% (mesenteric), 76.5% (subiliac), 55.9% (mandibular), and 7.4% (mediastinal) of samples. From the 87 typeable isolates, eight Salmonella enterica serotypes, including Kentucky (32.2%), Anatum (29.9%), Reading (17.2%), Meleagridis (12.6%), Cerro (4.6%), Muenster (1.1%), Give (1.1%), and Mbandaka (1.1%), were identified. S. Meleagridis was more likely (P = 0.03) to be recovered from lymph nodes than from feces or hides, whereas S. Kentucky was more likely (P = 0.02) to be recovered from feces and hides than from lymph nodes. The majority (59.3%) of the Salmonella isolates were pansusceptible; however, multidrug resistance was observed in 13.2% of isolates. Typing by PFGE revealed that Salmonella strains generally clustered by serotype, but some serotypes (Anatum, Kentucky, Meleagridis, and Reading) were comprised of multiple PFGE subtypes. Indistinguishable PFGE subtypes and, therefore, serotypes were isolated from multiple sample types, and multiple PFGE subtypes were commonly observed within an animal. Given the overrepresentation of some serotypes within lymph nodes, we hypothesize that certain Salmonella strains may be better at entering the bovine host than other Salmonella strains or that some may be better adapted for survival within lymph nodes. Our data provide insight into the ecology of Salmonella within cohorts of cattle and offer direction for intervention opportunities.


Asunto(s)
Enfermedades de los Bovinos/microbiología , Polimorfismo Genético , Salmonelosis Animal/microbiología , Salmonella/clasificación , Salmonella/genética , Mataderos , Animales , Bovinos , Enfermedades de los Bovinos/epidemiología , Farmacorresistencia Bacteriana Múltiple , Electroforesis en Gel de Campo Pulsado/veterinaria , Heces/microbiología , Ganglios Linfáticos/microbiología , México , Pruebas de Sensibilidad Microbiana/veterinaria , Filogenia , Salmonella/efectos de los fármacos , Salmonella/aislamiento & purificación , Salmonelosis Animal/epidemiología , Serotipificación/veterinaria , Piel/microbiología
4.
Foods ; 12(4)2023 Feb 18.
Artículo en Inglés | MEDLINE | ID: mdl-36832958

RESUMEN

The objective of this study was to evaluate the food safety efficacy of common antimicrobial interventions at and above required uptake levels for processing aids on the reduction of Shiga-toxin producing E. coli (STEC) and Salmonella spp. through spray and dip applications. Beef trim was inoculated with specific isolates of STEC or Salmonella strains. Trim was intervened with peracetic or lactic acid through spray or dip application. Meat rinses were serially diluted and plated following the drop dilution method; an enumerable range of 2-30 colonies was used to report results before log transformation. The combination of all treatments exhibits an average reduction rate of 0.16 LogCFU/g for STEC and Salmonella spp., suggesting that for every 1% increase in uptake there is an increase of 0.16 LogCFU/g of reduction rate. There is a statistical significance in the reduction rate of Shiga-toxin producing Escherichia coli in relation to the uptake percentage (p < 0.01). The addition of explanatory variables increases the R2 of the regression for STEC, where all the additional explanatory variables are statistically significant for reduction (p < 0.01). The addition of explanatory variables increases the R2 of the regression for Salmonella spp., but only trim type is statistically significant for reduction rate (p < 0.01). An increase in uptake percentages showed a significant increase in reduction rate of pathogens on beef trimmings.

5.
Foods ; 11(21)2022 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-36360077

RESUMEN

The objective of the study was to determine the impact of antimicrobial interventions and refrigerated dark storage on the shelf-life of pork chops. Boneless pork loins (n = 36) were split and stored for 1, 14, 28, and 42 days at 2-4 °C after being treated with the following antimicrobials: water (WAT), Bovibrom 225 ppm (BB225), Bovibrom 500 ppm (BB500), Fit Fresh 3 ppm (FF3), or washing solution 750 ppm (WS750). After the end of dark storage, pork loins were further processed and sliced into chops, overwrapped in trays, and displayed for up to an additional 96 h in a retail case. Instrumental and visual color measurements as well as mesophilic and psychrotrophic aerobic bacteria, and lactic acid bacteria were measured. BB500 and FF3 performed better in inhibiting the growth of indicator bacteria under 6 logs; however, FF3 presented the best stability for color during storage. Principal component analysis clustered initial dark storage days with a* and chroma while % discoloration, hue, b* and microorganisms where clustered with longer dark storage times. In general, treatment FF3 presented the best performance, both in inhibiting microbial growth and maintaining the stability of color, thus increasing the shelf-life of pork loins.

6.
Foods ; 10(5)2021 Apr 28.
Artículo en Inglés | MEDLINE | ID: mdl-33925048

RESUMEN

The use of antimicrobials in the pork industry is critical in order to ensure food safety and, at the same time, extend shelf life. The objective of the study was to determine the impact of antimicrobials on indicator bacteria on pork loins under long, dark, refrigerated storage conditions. Fresh boneless pork loins (n = 36) were split in five sections and treated with antimicrobials: Water (WAT), Bovibrom 225 ppm (BB225), Bovibrom 500 ppm (BB500), Fit Fresh 3 ppm (FF3), or Washing Solution 750 ppm (WS750). Sections were stored for 1, 14, 28, and 42 days at 2-4 °C. Mesophilic and psychrotrophic aerobic bacteria (APC-M, APC-P), lactic acid bacteria (LAB-M), coliforms, and Escherichia coli were enumerated before intervention, after intervention, and at each storage time. All bacterial enumeration data were converted into log10 for statistical analysis, and the Kruskal-Wallis test was used to find statistical differences (p < 0.05). Initial counts did not differ between treatments, while, after treatment interventions, treatment WS750 did not effectively reduce counts for APC-M, APC-P, and coliforms (p < 0.01). BB500, FF3, and WS750 performed better at inhibiting the growth of indicator bacteria when compared with water until 14 days of dark storage.

7.
Heliyon ; 7(7): e07547, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-34345734

RESUMEN

This research investigated the variations in the occurrence of Salmonella, STEC O157:H7 and non-O157 in the beef production chain in Colombia affected by seasons, hypothesizing that pathogen prevalence will be highest in the rainy season owing to soil moisture promoting bacteria multiplication and transfer between animals. To test this hypothesis, samples were obtained from five abattoirs, which represent 50% of the beef production in this country. A total of 1017 samples were collected, from which 606 were bovine feces, 206 were hide swabs, and 205 corresponded to carcass post-intervention. From the 1017 samples, 49.9% (n = 507) were collected during dry season, while 50.1% (n = 510) during rainy season. All samples (n = 1017) underwent screening for E. coli O157:H7 and Salmonella, while only a proportion of fecal samples (n = 339) were screened for the big six STEC serogroups and their virulence markers. The effect of season, age of animal and sex of animal were correlated with the prevalence results. A total of 84.7% of fecal samples carried virulence genes associated to STEC (stx or eae), suggesting that testing and control should be increased for the big-six STEC compared to E. coli O157:H7. Pathogen prevalence in feces was found to be 8.3%, 5.0%, and 51.0% for Salmonella, E. coli O157:H7 and STEC non-O157, respectively. Hides had a prevalence of 15.0% and 6.8% of Salmonella and E. coli O157:H7, respectively. Carcasses post-intervention were found to have 4.4% and 2.5% prevalence of Salmonella and E. coli O157:H7, respectively. A seasonal effect was found for fecal samples. E. coli O157 and non-O157 STEC shedding were significantly higher (P ≤ 0.05) during rainy season compared to dry season. In contrast, hides and carcasses were more likely to present lower incidence of pathogens during rainy months compared to dry season; however, it was significant only for Salmonella on carcasses with estimated odds of detection almost six times higher in the dry season relative to the rainy season (OR = 5.90, 95% CI 1.18-29.57).

8.
Foods ; 10(5)2021 May 04.
Artículo en Inglés | MEDLINE | ID: mdl-34064320

RESUMEN

The purpose of this study was to evaluate the antimicrobial efficacy of an aqueous ozone (Bio-Safe) treatment and lactic acid solutions on natural microbiota and E. coli O157:H7 and Salmonella surrogates on beef carcasses and trim in a commercial beef processing plant. For every repetition, 40 carcass and 40 trim swabs (500 cm2) were collected. Samples were taken using EZ-ReachTM swabs, and plated into aerobic plate count (APC), coliform, and E. coli PetrifilmTM for enumeration. In addition, a five-strain cocktail (MP-26) of E. coli surrogates was inoculated onto trim. For every trim surrogate repetition, 30 trim pieces were sampled after attachment and after ozone intervention. Samples were diluted and counts were determined using the TEMPO® system for E. coli enumeration. Ozone and lactic acid interventions significantly reduced (p < 0.003) bacterial counts in carcasses and trim samples. Moreover, lactic acid further reduced APC and coliforms in trim samples compared to ozone intervention (p < 0.009). In the surrogate trials, ozone significantly reduced (p < 0.001) surrogate concentration. Historical data from the plant revealed a reduction (p < 0.001) of presumptive E. coli O157:H7 in trim after a full year of ozone intervention implementation. The novel technology for ozone generation and application as an antimicrobial can become an alternative option that may also act synergistically with existing interventions, minimizing the risk of pathogens such as Salmonella and E. coli O157:H7.

9.
Foods ; 10(9)2021 Sep 06.
Artículo en Inglés | MEDLINE | ID: mdl-34574215

RESUMEN

The objective of this experiment was to compare the antimicrobial efficacy of an aqueous ozone intervention and a lactic acid solution on natural microbiota of variety meats in a commercial beef processing plant. EZ-Reach™ swabs were used to collect 100 cm2 area samples before and after ozone and lactic acid intervention application for three different offals (head, heart, and liver). Each repetition included 54 samples per variety meat and antimicrobial for a total of 162 samples per repetition. Enumeration of total aerobic bacteria (APC) and Escherichia coli (EC) was performed on each sample. Microbial counts for both microorganisms evaluated were significantly reduced (p < 0.001) after lactic acid immersion (2-5%) and ozone intervention for all variety meats, with the exception of ozone intervention in EC counts of the heart samples. APC after lactic acid intervention was reduced on average by 1.73, 1.66, and 1.50 Log CFU/sample in the head, heart, and liver, respectively, while after ozone intervention, counts were reduced on average by 1.66, 0.52, and 1.20 Log CFU/sample. EC counts after lactic acid intervention were reduced on average by 0.96, 0.79, and 1.00 Log CFU/sample in the head, heart, and liver, respectively, while after ozone intervention, counts were reduced on average by 0.75, 0.62, and 1.25 Log CFU/sample. The aqueous ozone antimicrobial scheme proved to be a promising intervention for the in-plant reduction of indicator levels in variety meats, specifically heads, hearts, and livers.

10.
J Food Prot ; 72(8): 1616-23, 2009 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-19722392

RESUMEN

After three different outbreaks were linked to the consumption of nonintact meat products contaminated with Escherichia coli O157:H7, the U.S. Department of Agriculture, Food Safety and Inspection Service published notice requiring establishments producing mechanically tenderized and moisture-enhanced beef products to reassess their respective hazard analysis and critical control point system, due to potential risk to the consumers. The purpose of this study was to determine the effectiveness of different intervention strategies (lactic acid, lactic acid bacteria, and acidified sodium chlorite) to control E. coli O157:H7 and Salmonella enterica serotype Typhimurium definitive phage type 104 in mechanically tenderized and brine-enhanced beef strip loins when applied to the steaks prior to packaging and shipment for processing. After the mechanical process, translocation of E. coli O157:H7 and Salmonella Typhimurium DT 104 from the surface into the internal muscles occurred at levels between 2.0 and 4.0 log CFU/g (from an initial inoculation level of 5.0 log) after mechanical tenderization, and at levels of 1.0 to 3.0 log CFU/g after injection, with all the interventions consistently presenting lower microbial counts (P < 0.05) than did the controls. Lactic acid bacteria reduced internal E. coli O157:H7 loads 1.2 to > 2.2 log cycles, while the acidified sodium chlorite and lactic acid reduced them between 0.8 and 3.0 log, respectively. Salmonella Typhimurium DT 104 was also reduced internally after application of all interventions between 0.9 and 2.2 log. The application of antimicrobials to the steaks prior to packaging and shipment on day 0 was effective in reducing internalization of both pathogens in nonintact beef products stored for both 14 and 21 days.


Asunto(s)
Desinfectantes/farmacología , Escherichia coli O157/crecimiento & desarrollo , Manipulación de Alimentos/normas , Productos de la Carne/microbiología , Salmonella typhimurium/crecimiento & desarrollo , Animales , Antibiosis , Bovinos , Cloruros/farmacología , Recuento de Colonia Microbiana , Seguridad de Productos para el Consumidor , Desinfección , Escherichia coli O157/efectos de los fármacos , Contaminación de Alimentos/prevención & control , Manipulación de Alimentos/métodos , Microbiología de Alimentos , Humanos , Ácido Láctico/farmacología , Lactobacillaceae/fisiología , Medición de Riesgo , Salmonella typhimurium/efectos de los fármacos , Factores de Tiempo
11.
J Food Prot ; 82(4): 677-683, 2019 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-30917035

RESUMEN

Imported meat in the United States can become a food safety hazard if proper food safety programs are not fully implemented in foreign meat processing plants. Thus, exporting countries' food safety inspection systems must be equivalent to the U.S. federal inspection system to become eligible to export meat to the United States. The objective of this study was to validate the beef harvest Hazard Analysis and Critical Control Points and food safety programs of two beef processing plants in Honduras operating under U.S. equivalency standards by evaluating the presence of Salmonella (plant A) and Shiga toxin-producing Escherichia coli (STEC; plant B) on hides. Additionally, evaluating pathogen transfer from hides to carcasses, as detected by preevisceration sampling, and the mitigation of transferred pathogens, by application of carcass spray interventions and determination of Salmonella presence in lymph nodes, was also conducted. In plant A, the presence of Salmonella on hides ( n = 30 of 687; 4.4%) was significantly greater ( P < 0.10) than on carcasses swabbed at preevisceration ( n = 7 of 687; 1.0%), after intervention ( n = 13 of 678; 1.9%), and in lymph nodes ( n = 14 of 691; 2.0%). In plant B, Salmonella was not detected on hide samples; therefore, data could not be used for validation of the harvest Hazard Analysis and Critical Control Points program. Alternatively, STEC presence on hides ( n = 21 of 85; 24.7%) was greater ( P < 0.10) than on carcasses at preevisceration ( n = 3 of 85; 3.5%) and after intervention ( n = 1 of 85; 1.2%). Pathogen presence in plant B did not differ ( P = 0.306) between carcasses in preevisceration and postintervention stages; both, however, were substantially low. Both plants' controls effectively reduced Salmonella and STEC presence in postintervention carcasses.


Asunto(s)
Escherichia coli O157 , Carne Roja , Mataderos , Animales , Bovinos , Recuento de Colonia Microbiana , Microbiología de Alimentos , Honduras , Estados Unidos
12.
J Food Prot ; 81(1): 54-58, 2018 01.
Artículo en Inglés | MEDLINE | ID: mdl-29257727

RESUMEN

Thermal inactivation of Salmonella is a critical component of the calculated thermal process to ensure the safety of cooked human and animal products. However, lethality performance standards for meat processing by-products that may harbor Salmonella have not been properly set under the actual conditions of rendering processes. The goal of this study was to evaluate the thermal inactivation parameters for Salmonella in high-fat beef trimmings as a model system for animal food products treated under simulated "worst-case scenario" commercial rendering conditions. Ground high-fat beef trimmings (50% fat) were artificially inoculated with a 108 CFU/g Salmonella cocktail containing human outbreak strains including the highly thermotolerant serotype Salmonella Senftenberg. The meat samples were packaged and immersed in either water or silicon oil at predetermined temperatures ranging from 60 to 121°C (from 140 to 250°F). D-values of Salmonella at each temperature were calculated from the negative inverse slope of the log CFU per gram versus time plot. The z-values were determined from the negative inverse slope of the log D versus temperature plot. The D-values in thermal death curves for low-fat (20%) content materials (between 60 and 95°C) were 2.175, 0.658, 0.237, 1.563, 0.356, 0.284, 0.264, and 0.201 min, whereas materials with 50% fat (between 100 to 121°C) were 0.277, 0.286, 0.159, 0.143, 0.137, and 0.087 min. The z-values for low- and high-temperature schedules were 43.7 and 42.9°C, respectively. Thermal lethality data for Salmonella inactivation in high-fat rendering raw materials will help animal food processors design adequate thermal processing schedules and support critical control points to ensure the safety of final beef-based rendered products.


Asunto(s)
Productos de la Carne/microbiología , Salmonella/crecimiento & desarrollo , Animales , Bovinos , Culinaria , Manipulación de Alimentos/métodos , Microbiología de Alimentos , Calor , Humanos
13.
Meat Sci ; 135: 1-5, 2018 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-28843145

RESUMEN

The objective of this study was to evaluate the frequency of Salmonella and E. coli O157 found on the hides, as well as presence of Salmonella, Campylobacter and E. coli O157 found in small-ruminant fecal samples from abattoirs and farms in California, New Mexico, Texas, Mexico and the Bahamas. In small-ruminant fecal samples, overall organism presence was identified as 13.9% Salmonella (n=532), 15.3% E. coli O157 (n=477) and 80.7% Campylobacter (n=176). Overall, on small-ruminant hide surfaces, Salmonella frequency was 17.1% (N=339) and E. coli O157 was detected at 1.5% (n=266). The overall lower detection (P<0.0001) of E. coli O157 from hide samples (1.5%) when compared to presence in fecal samples (15.3%), is not consistent with trends expected. Results from this study can be used to better understand and potentially control pathogens in small-ruminants utilized for meat and milk.


Asunto(s)
Campylobacter/aislamiento & purificación , Escherichia coli O157/aislamiento & purificación , Cabras/microbiología , Salmonella/aislamiento & purificación , Ovinos/microbiología , Mataderos , Crianza de Animales Domésticos , Animales , Bahamas/epidemiología , Heces/microbiología , México/epidemiología , Piel/microbiología , Estados Unidos/epidemiología
14.
Am J Vet Res ; 68(5): 501-7, 2007 May.
Artículo en Inglés | MEDLINE | ID: mdl-17472449

RESUMEN

OBJECTIVE: To determine effects of administration of ceftiofur crystalline-free acid (CCFA) on antimicrobial susceptibility of Escherichia coli in feedlot cattle. ANIMALS: 61 feedlot steers. PROCEDURES: A cohort study was conducted. Steers were housed in pens (5 pens with 10 steers and 1 pen with 11 steers). Five steers in each pen were administered CCFA, and 5 served as control steers (1 pen had 6 control steers). The CCFA administration included a single-dose regimen (6.6 mg/kg, SC, on day 0), two-thirds-dose regimen (4.4 mg/kg, SC, on day 0), and 3-dose regimen (6.6 mg/kg, SC, on days 0, 6, and 13). Fecal samples were collected on days 0, 2, 6, 9, 13, 16, 20, and 28. Fecal samples were collected immediately before CCFA administration. Minimum inhibitory concentrations of 15 antimicrobials were determined for 3 E coli isolates/fecal sample. Escherichia coli were enumerated by use of direct-plating techniques. RESULTS: Resistance to 1 or more antimicrobials was detected in 986 of 1,441 (68.4%) isolates recovered. Administration of CCFA was associated with a transient increase in the population of ceftiofur-resistant isolates. Susceptibility returned to day 0 values (ie, samples collected immediately before CCFA administration) approximately 2 weeks after completion of CCFA administration. Agreement between ceftiofur resistance and co-resistance to ampicillin, chloramphenicol, streptomycin, sulfisoxazole, and tetracycline was almost perfect (kappa 0.97). We did not detect variation in susceptibility of E coli recovered from commingled control steers. CONCLUSIONS AND CLINICAL RELEVANCE: Administration of CCFA provided selection pressure that favored transient expansion of multiple-resistant variants.


Asunto(s)
Bovinos/microbiología , Cefalosporinas/administración & dosificación , Cefalosporinas/farmacología , Farmacorresistencia Bacteriana Múltiple/efectos de los fármacos , Escherichia coli/efectos de los fármacos , Alimentación Animal/análisis , Animales , Antibacterianos/administración & dosificación , Antibacterianos/farmacología , Dieta/veterinaria , Relación Dosis-Respuesta a Droga , Masculino , Pruebas de Sensibilidad Microbiana , Factores de Tiempo
15.
Am J Vet Res ; 66(12): 2023-7, 2005 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-16379641

RESUMEN

OBJECTIVE: To evaluate site-to-site variation within fecal pats from cattle with regard to detection of Escherichia coli O157 and determine the effect on the accuracy of prevalence estimates of assay of multiple samples collected from the same fecal pat. SAMPLE POPULATION: 120 freshly voided fecal pats collected from 2 beef feedlots. Procedures-5 samples were systematically collected from each fecal pat and analyzed for E coli O157 via selective preenrichment techniques, immunomagnetic separation, and biochemical tests. Presumptive isolates were definitively identified via agglutination assays and polymerase chain reaction techniques. Best estimators of prevalence were calculated from the distribution of E coli O157-positive samples per pat. RESULTS: Of the 120 fecal pats, 96, 13, 4, 2, 3, and 2 fecal pats had 0, 1, 2, 3, 4, and 5 E coli O157-positive samples, respectively. The greatest estimate of E coli O157 prevalence (20%) was achieved when all 5 samples were assessed; this estimate represented a 2.4- fold increase in prevalence, compared with that provided via analysis of 1 sample/pat (8.2%). Compared with assessment of 5 sites/pat, the relative sensitivity of detecting an E coli O157-positive fecal pat via analysis of 1 site/pat was 40.1%. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that estimates of E coli O157 prevalence derived from sampling of 1 location/pat are likely underestimates of the true prevalence of this pathogen in fecal pats (and by extension, cattle). Additional research is warranted to confirm these results in situations of high and low prevalence and across different feedlots.


Asunto(s)
Enfermedades de los Bovinos/epidemiología , Enfermedades de los Bovinos/microbiología , Reservorios de Enfermedades/microbiología , Infecciones por Escherichia coli/veterinaria , Escherichia coli O157/aislamiento & purificación , Heces/microbiología , Animales , Bovinos , Infecciones por Escherichia coli/epidemiología , Prevalencia , Tamaño de la Muestra , Texas/epidemiología
16.
J Food Prot ; 78(2): 264-72, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25710140

RESUMEN

The objective of the study was to characterize virulence genes and subtype Escherichia coli O157:H7 and O157:H( 2 ) isolates obtained from a vertically integrated feedlot slaughter plant in Mexico. A total of 1,695 samples were collected from feedlots, holding pens, colon contents, hides, and carcasses. E. coli O157:H7 detection and confirmation was carried out using conventional microbiology techniques, immunomagnetic separation, latex agglutination, and the BAX system. A total of 97 E. coli O157 strains were recovered and screened for key virulence and metabolic genes using multiplex and conventional PCR. Eighty-eight (91.72%) of the strains carried stx2, eae, and ehxA genes. Ten isolates (8.25%) were atypical sorbitol-fermenting strains, and nine were negative for the flicH7 gene and lacked eae, stx1, stx2, and ehxA. One sorbitol-positive strain carried stx2, eae, tir, toxB, and iha genes but was negative for stx1 and ehxA. Pulsed-field gel electrophoresis (PFGE) analysis yielded 49 different PFGE subtypes, showing a high genetic diversity; however, the majority of the typical isolates were closely related (80 to 90% cutoff). Atypical O157 isolates were not closely related within them or to typical E. coli O157:H7 isolates. Identical PFGE subtypes were found in samples obtained from colon contents, feedlots, holding pens, and carcasses. Isolation of a sorbitolfermenting E. coli O157 positive for a number of virulence genes is a novel finding in Mexico. These data showed that genetically similar strains of E. coli O157:H7 can be found at various stages of beef production and highlights the importance of preventing cross-contamination at the pre- and postharvest stages of processing.


Asunto(s)
Escherichia coli O157/aislamiento & purificación , Heces/microbiología , Carne/microbiología , Animales , Técnicas de Tipificación Bacteriana , Bovinos , Electroforesis en Gel de Campo Pulsado , Escherichia coli O157/clasificación , Contaminación de Alimentos/análisis , Microbiología de Alimentos , Separación Inmunomagnética , México , Reacción en Cadena de la Polimerasa , Factores de Virulencia/genética
17.
J Food Prot ; 78(3): 498-502, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-25719872

RESUMEN

Salmonella continues to cause a considerable number of foodborne illnesses worldwide. The sources of outbreaks include contaminated meat and produce. The purpose of this study was to establish an initial investigation of the burden of Salmonella in produce and beef from Honduras by sampling retail markets and abattoirs. Retail produce samples (cantaloupes, cilantro, cucumbers, leafy greens, peppers, and tomatoes; n = 573) were purchased in three major cities of Honduras, and retail whole-muscle beef (n = 555) samples were also purchased in four major cities. Additionally, both hide and beef carcass (n = 141) samples were collected from two Honduran abattoirs. Whole-muscle beef samples were obtained using a sponge hydrated with buffered peptone water, and 10 ml of the buffered peptone water rinsate of each produce sample was collected with a dry sponge and placed in a bag to be transported back to the United States. Salmonella was detected using a commercially available, closeplatform PCR system, and positive samples were subjected to culture on selective media to obtain isolates. Overall, the prevalence of Salmonella-positive samples, based on PCR detection in Honduras (n = 555) retail beef was 10.1% (95% confidence interval = 7.8, 12.9), whereas 7.8% (n = 141) of beef carcass and hides samples were positive in both beef plants. The overall Salmonella prevalence for all produce samples (n = 573) collected was 2.1% (95% confidence interval = 1.2, 3.6). The most common serotypes identified in Honduras were Salmonella Typhimurium followed by Derby. These results provide an indication of Salmonella contamination of beef and produce in Honduras. Developing a Salmonella baseline for Latin America through an initial investigation like the one presented here contributes to a broader global understanding of the potential exposure through food, thus providing insight into the needs for control strategies.


Asunto(s)
Carne/microbiología , Plantas Comestibles/microbiología , Salmonella/aislamiento & purificación , Mataderos , Animales , Bovinos/microbiología , ADN Bacteriano/análisis , Microbiología de Alimentos , Enfermedades Transmitidas por los Alimentos/microbiología , Frutas/microbiología , Honduras , Reacción en Cadena de la Polimerasa , Salmonella/clasificación , Salmonella/genética , Serotipificación , Estados Unidos
18.
J Food Prot ; 78(3): 511-7, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-25719874

RESUMEN

Non-O157 Shiga toxin-producing Escherichia coli (STEC) is an emerging risk for food safety. Although numerous postharvest antimicrobial interventions have been effectively used to control E. coli O157:H7 during beef harvesting, research regarding their effectiveness against non-O157 STEC is scarce. The objectives of this study were (i) to evaluate effects of the spray treatments-ambient water, 5% lactic acid (LA), 200 ppm of hypobromous acid (HA), and 200 ppm of peroxyacetic acid (PA)-on the reduction of O157:H7 or non-O157 STEC (O26, O103, O111, and O145) with high (10(6) log CFU/50 cm(2)) or low (10(2) log CFU/50 cm(2)) levels on beef subprimals after vacuum storage for 14 days and (ii) to evaluate the association of the antimicrobial treatments and cooking (50 or 70°C) on the reduction of the pathogens in blade-tenderized steaks. The treatment effects were only observed (P = 0.012) on samples taken immediately after spray intervention treatment following inoculation with a high level of O157:H7. The LA and PA treatments significantly reduced low-inoculated non-O157 STEC after spray intervention; further, the LA and HA treatments resulted in significant reductions of non-O157 STEC on the low-inoculated samples after storage. Although cooking effectively reduced the detection of pathogens in internal steak samples, internalized E. coli O157:H7 and non-O157 STEC were able to survive in steaks cooked to a medium degree of doneness (70°C). This study indicated that the reduction on surface populations was not sufficient enough to eliminate the pathogen's detection following vacuum storage, mechanical tenderization, and cooking. Nevertheless, the findings of this study emphasize the necessity for a multihurdle approach and further investigations of factors that may influence thermal tolerance of internalized pathogenic STEC.


Asunto(s)
Antiinfecciosos/farmacología , Escherichia coli O157/efectos de los fármacos , Escherichia coli/efectos de los fármacos , Carne/microbiología , Escherichia coli Shiga-Toxigénica/efectos de los fármacos , Animales , Bromatos/administración & dosificación , Bovinos , Recuento de Colonia Microbiana , Culinaria , Escherichia coli/aislamiento & purificación , Escherichia coli O157/aislamiento & purificación , Manipulación de Alimentos/instrumentación , Manipulación de Alimentos/métodos , Microbiología de Alimentos , Inocuidad de los Alimentos , Almacenamiento de Alimentos/métodos , Calor , Ácido Láctico/administración & dosificación , Ácido Peracético/administración & dosificación , Escherichia coli Shiga-Toxigénica/aislamiento & purificación , Vacio
19.
Meat Sci ; 110: 196-200, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26241466

RESUMEN

The prevalence of potentially positive Shiga toxin-producing Escherichia coli (STEC) bovine hides and carcasses in three abattoirs in Costa Rica was estimated. Two export facilities (A and B) and one non-export establishment (C) were visited during the dry and rainy seasons of 2013. Swabs of hides pre-eviscerated and treated (180-220 peroxyacetic acid spray) carcasses were tested for the potential presence of STEC serogroups O26, O45, O103, O111, O121, and O145. The prevalence on hides during the rainy season was 86.7, 96.7 and 96.7% for facilities A, B, and C, respectively. During the dry season, the prevalence on hides was significantly lower in plants A and B (40% and 26.7%, respectively), but was marginally associated with the season in plant C (76.7%, P=0.0523). The prevalence of non-O157 STEC markers on treated carcasses was low (0 to 3.3%), suggesting that all plants were effective in minimizing the target non-O157 STEC in beef destined for export and for domestic consumption.


Asunto(s)
Bovinos/microbiología , Escherichia coli/aislamiento & purificación , Estaciones del Año , Toxinas Shiga/metabolismo , Piel/microbiología , Mataderos , Animales , Costa Rica , Escherichia coli/clasificación , Escherichia coli/metabolismo
20.
Rev. neurol. (Ed. impr.) ; 69(6): 235-241, 16 sept., 2019. tab, graf
Artículo en Español | IBECS (España) | ID: ibc-192217

RESUMEN

Introducción. El deterioro cognitivo vascular mayor tiene una alta prevalencia en la población mayor de 60 años. El diagnóstico es complejo y existen múltiples criterios con alto grado de heterogeneidad entre ellos. Se requieren estudios de validación de los criterios VASCOG y la comparación con los otros grupos de criterios disponibles para el diagnóstico de deterioro cognitivo vascular mayor. Objetivo. Comparar los criterios NINDS-AIREN y VASCOG para el diagnóstico de deterioro cognitivo vascular mayor en una clínica de memoria. Pacientes y métodos. Se realizó un estudio descriptivo observacional de corte transversal analítico en adultos mayores que asistieron a una clínica de memoria universitaria durante un año. Se recopiló la historia clínica de los pacientes, se verificaron los criterios de inclusión y exclusión y se aplicaron los criterios NINDS-AIREN y VASCOG. Posteriormente se evaluaron los resultados de la resonancia magnética cerebral y se aplicaron nuevamente los criterios definidos. Resultados. La frecuencia de diagnóstico de deterioro cognitivo vascular mayor fue mayor utilizando los criterios VASCOG. La concordancia entre los criterios NINDS-AIREN y VASCOG fue muy alta (100%), con un nivel de consistencia sustancial (kappa = 0,698) para un diagnóstico definitivo. Antes de realizar la resonancia, el nivel de concordancia se redujo (55,6%), con un nivel de consistencia sustancial (kappa = 0,620). Conclusiones. Los criterios NINDS-AIREN y VASCOG tienen un alto nivel de consistencia para el diagnóstico de deterioro cognitivo vascular mayor, con un nivel moderado de concordancia en los criterios clínicos. Dependiendo de los criterios utilizados, la prevalencia de diagnóstico cambia y es mayor para los criterios VASCOG


Introduction. Major vascular cognitive impairment has a high prevalence in elder population over 60 years old. Its diagnosis is complex, and there are multiple criteria with a high degree of heterogeneity between them. Validation studies of the VASCOG criteria are required, and comparison with the other groups of criteria available for the diagnosis of major vascular cognitive impairment. Aim. To compare NINDS-AIREN and VASCOG criteria to diagnose major vascular cognitive impairment in a memory clinic. Patients and methods. An analytical transversal observational study was performed in elder adults who attended to university memory clinic for one year. Clinical records of patients were collected, verifying inclusion and exclusion criteria by applying NINDS-AIREN and VASCOG criteria. Subsequently cerebral magnetic resonance imaging results were assessed and yet again defined criteria were applied. Results. Major vascular cognitive impairment diagnosis rate was greater by applying VASCOG criteria. Concordance between NINDS-AIREN and VASCOG criteria was very high (100%), with a substantial consistence level (kappa = 0.698) for a final diagnosis. Before performing a magnetic resonance imaging, concordance level was reduced (55.6%) with a substantial consistence level (kappa = 0.620). Conclusions. NINDS-AIREN and VASCOG criteria have a high consistence level for major vascular cognitive impairment diagnosis, with a moderate concordance level in clinical criteria, to different assessed domains. Depending on criteria used, diagnosis prevalence changes, being higher with VASCOG criteria


Asunto(s)
Humanos , Masculino , Femenino , Persona de Mediana Edad , Anciano , Anciano de 80 o más Años , Trastornos del Conocimiento/diagnóstico , Trastornos del Conocimiento/etiología , Trastornos Cerebrovasculares/complicaciones , Imagen por Resonancia Magnética , Sensibilidad y Especificidad , Estudios Transversales
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA