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1.
Proc Natl Acad Sci U S A ; 118(21)2021 05 25.
Artículo en Inglés | MEDLINE | ID: mdl-34001598

RESUMEN

Collective intelligence (CI) is critical to solving many scientific, business, and other problems, but groups often fail to achieve it. Here, we analyze data on group performance from 22 studies, including 5,279 individuals in 1,356 groups. Our results support the conclusion that a robust CI factor characterizes a group's ability to work together across a diverse set of tasks. We further show that CI is predicted by the proportion of women in the group, mediated by average social perceptiveness of group members, and that it predicts performance on various out-of-sample criterion tasks. We also find that, overall, group collaboration process is more important in predicting CI than the skill of individual members.


Asunto(s)
Inteligencia/fisiología , Reuniones Masivas , Percepción Social/psicología , Adolescente , Adulto , Anciano , Femenino , Procesos de Grupo , Humanos , Masculino , Persona de Mediana Edad , Estados Unidos , Adulto Joven
2.
Ecotoxicol Environ Saf ; 149: 36-42, 2018 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-29145163

RESUMEN

Wastewater treatment plants (WWTPs) that release treated wastewater into the environment have emerged as a major threat to public health. In this study, we investigated Escherichia coli load and antibiotic-resistance profiles across different treatment processes at a swine farm WWTP. The frequency of the detection of class 1 and 2 integrons, and their association with antibiotic resistance, were also analyzed. Samples were obtained at each of five sampling sites that represented each processing step within the WWTP. The largest decrease in E. coli load was observed during the anaerobic digestion step (from 4.86 to 2.89log CFU/mL). Isolates resistant to ß-lactam antibiotics were efficiently removed after a series of treatment steps, whereas the proportions of isolates resistant to non-ß-lactam antibiotics and multidrug-resistant strains were maintained across treatments. The occurrence of integron-positive strains was not significantly different at the various sampling sites (43.4-70%; p>0.05). Of the class 1 integron-positive isolates, 17.9% harbored the integron-associated gene cassettes aadA2, aadA12, aadA22, and dfrA15. To the best of our knowledge, this is the first description of a class 1 integron containing the aadA12 gene cassette from a swine farm and the presence of a class 1 integron containing dfrA15 in E. coli. This suggests that novel antibiotic-resistance gene cassette arrays could be generated in swine farm WWTPs. Moreover, 75% of integron-positive strains were categorized as multidrug resistant, whereas only 15.4% of integron-negative strains were multidrug resistant (p<0.05), indicating that integrons may be responsible for mediating resistance in WWTPs. With regard to the occurrence of multidrug-resistant, integron-positive E. coli recovered from the final effluent, our results highlighted the potential risks associated with wastewater discharge from swine farm WWTPs in terms of the spread of antibiotic-resistant bacteria to the aquatic environment.


Asunto(s)
Antibacterianos/farmacología , Farmacorresistencia Bacteriana Múltiple/genética , Escherichia coli/efectos de los fármacos , Integrones/genética , Aguas Residuales/química , Purificación del Agua/métodos , Animales , Escherichia coli/genética , Granjas , Porcinos , Aguas Residuales/microbiología
3.
Foodborne Pathog Dis ; 14(2): 84-88, 2017 02.
Artículo en Inglés | MEDLINE | ID: mdl-28051328

RESUMEN

Culture-based detection of nontyphoidal Salmonella spp. in foods requires at least four working days; therefore, new detection methods that shorten the test time are needed. In this study, we developed a novel single-step Salmonella enrichment broth, SSE-1, and compared its detection capability with that of commercial single-step ONE broth-Salmonella (OBS) medium and a conventional two-step enrichment method using buffered peptone water and Rappaport-Vassiliadis soy broth (BPW-RVS). Minimally processed lettuce samples were artificially inoculated with low levels of healthy and cold-injured Salmonella Enteritidis (100 or 101 colony-forming unit/25 g), incubated in OBS, BPW-RVS, and SSE-1 broths, and streaked on xylose lysine deoxycholate (XLD) agar. Salmonella recoverability was significantly higher in BPW-RVS (79.2%) and SSE-1 (83.3%) compared to OBS (39.3%) (p < 0.05). Our data suggest that the SSE-1 single-step enrichment broth could completely replace two-step enrichment with reduced enrichment time from 48 to 24 h, performing better than commercial single-step enrichment medium in the conventional nonchromogenic Salmonella detection, thus saving time, labor, and cost.


Asunto(s)
Medios de Cultivo/química , Contaminación de Alimentos/análisis , Microbiología de Alimentos/métodos , Salmonella enteritidis/aislamiento & purificación , Verduras/microbiología , Recuento de Colonia Microbiana , Lactuca/microbiología , Salmonella enteritidis/crecimiento & desarrollo
4.
Foodborne Pathog Dis ; 13(5): 251-4, 2016 05.
Artículo en Inglés | MEDLINE | ID: mdl-27043031

RESUMEN

Overgrowth of extended-spectrum ß-lactamase (ESBL)-producing Escherichia coli on modified charcoal-cefoperazone-deoxycholate agar (mCCDA) is the most common confounding factor for the isolation of Campylobacter from poultry samples. mCCDA modified by supplementation with tazobactam, an ESBL inhibitor, was evaluated for Campylobacter isolation from chicken carcass rinse with regard to isolation rate and selectivity. In total, 120 whole chicken carcasses purchased from retail stores were rinsed with buffered peptone water enriched with 2× blood-free Bolton broth at 42°C for 48 h and then inoculated onto mCCDA with and without tazobactam supplementation (mCCDA or T-mCCDA) at 42°C for 48 h under microaerobic conditions. Suspect colonies were subcultured and confirmed by colony PCR. Plates with tazobactam exhibited a higher Campylobacter isolation rate (56.7% vs. 30.8%, p < 0.05) and selectivity (0.8 vs. 83.3% plates contaminated with non-Campylobacter, p < 0.05) than mCCDA. Thus, tazobactam-supplemented mCCDA would be a useful option for qualitative detection of Campylobacter in chicken carcass rinse.


Asunto(s)
Agar/farmacología , Antibacterianos/farmacología , Campylobacter/aislamiento & purificación , Microbiología de Alimentos , Ácido Penicilánico/análogos & derivados , Animales , Campylobacter/efectos de los fármacos , Campylobacter/fisiología , Carbón Orgánico/farmacología , Pollos/microbiología , Medios de Cultivo , Ácido Desoxicólico/farmacología , Ácido Penicilánico/farmacología , Tazobactam
5.
Foodborne Pathog Dis ; 13(12): 656-660, 2016 12.
Artículo en Inglés | MEDLINE | ID: mdl-27992273

RESUMEN

Organic foods have risen in popularity recently. However, the increased risk of bacterial contamination of organic foods has not been fully evaluated. In this study, 100 samples each of organic and conventional fresh vegetables (55 lettuce samples and 45 sprout samples) sold in South Korea were analyzed for aerobic bacteria, coliforms, Escherichia coli, and Bacillus cereus. Although the aerobic bacteria and coliform counts were not significantly different between the two farming types (p > 0.05), the occurrence rate of B. cereus was higher in organically cultivated vegetables compared with those grown conventionally (70% vs. 30%, respectively). The mean contamination level of B. cereus-positive organic samples was also significantly higher (1.86 log colony-forming unit [CFU]/g vs. 0.69 log CFU/g, respectively) (p < 0.05). In addition, six samples of organic vegetables were found to be contaminated with B. cereus at over 4 log CFU/g categorized as unsatisfactory according to Health Protection Agency guideline. The relatively higher occurrence rate of B. cereus in organic vegetables emphasizes the importance of implementing control measures in organic vegetable production and postharvest processing to reduce the risk of food poisoning.


Asunto(s)
Bacillus cereus/aislamiento & purificación , Contaminación de Alimentos , Calidad de los Alimentos , Alimentos Orgánicos/microbiología , Verduras/microbiología , Bacillus cereus/crecimiento & desarrollo , Recuento de Colonia Microbiana , Enterobacteriaceae/crecimiento & desarrollo , Enterobacteriaceae/aislamiento & purificación , Escherichia coli/crecimiento & desarrollo , Escherichia coli/aislamiento & purificación , Inspección de Alimentos , Conservación de Alimentos , Alimentos Orgánicos/efectos adversos , Alimentos Orgánicos/economía , Alimentos Orgánicos/normas , Enfermedades Transmitidas por los Alimentos/epidemiología , Enfermedades Transmitidas por los Alimentos/etiología , Enfermedades Transmitidas por los Alimentos/microbiología , Enfermedades Transmitidas por los Alimentos/prevención & control , Bacterias Aerobias Gramnegativas/crecimiento & desarrollo , Bacterias Aerobias Gramnegativas/aislamiento & purificación , Bacterias Grampositivas/crecimiento & desarrollo , Bacterias Grampositivas/aislamiento & purificación , Guías como Asunto , Humanos , Lactuca/economía , Lactuca/crecimiento & desarrollo , Lactuca/microbiología , Lactuca/normas , Hojas de la Planta/efectos adversos , Hojas de la Planta/crecimiento & desarrollo , Hojas de la Planta/microbiología , Práctica de Salud Pública , Control de Calidad , República de Corea/epidemiología , Riesgo , Plantones/efectos adversos , Plantones/crecimiento & desarrollo , Plantones/microbiología , Verduras/economía , Verduras/crecimiento & desarrollo , Verduras/normas
6.
Foodborne Pathog Dis ; 12(3): 190-6, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-25692653

RESUMEN

The emergence of antibiotic-resistant foodborne Salmonella has become a major public health problem. Consumption of undercooked poultry contaminated with Salmonella can induce food poisoning in humans. In this study, we investigated the occurrence and antibiotic resistance patterns of Salmonella spp. isolated from 120 chicken carcasses produced in 6 poultry slaughterhouses in South Korea. A total of 11 samples (9.2%) were found contaminated with Salmonella: 5 isolates were serotyped as Salmonella Bellevue strain (slaughterhouse C) and 6 isolates were serotyped as Salmonella Enteritidis strain (slaughterhouse E). Salmonella Bellevue isolates were resistant to five antibiotics (ampicillin, chloramphenicol, nalidixic acid, tetracycline, and trimethoprim/sulfamethoxazole), while Salmonella Enteritidis isolates were resistant to nine antibiotics (ampicillin, cefotaxime, ceftazidime, cefazolin, cephalothin, amikacin, nalidixic acid, streptomycin, and tetracycline). All cephalosporin-resistant Salmonella Enteritidis isolates exhibited the extended-spectrum ß-lactamase (ESBL) phenotype and carried the gene encoding CTX-M-15, the most prevalent ESBL enzyme worldwide. Based on molecular subtyping performed using the automated rep-polymerase chain reaction (PCR) system (DiversiLab), the isolates showing ≥ 95 similarity in their rep-PCR banding patterns were classified into 5 pulsotypes. Given that cephalosporins are the drugs of choice for invasive Salmonella infections, the high incidence of ESBL-producing strains in chicken should emphasize the necessity of regular monitoring of the occurrence of antibiotic-resistant ESBL-positive Salmonella strains in poultry meat.


Asunto(s)
Pollos/microbiología , Farmacorresistencia Bacteriana Múltiple/genética , Salmonelosis Animal/epidemiología , Salmonella enteritidis/aislamiento & purificación , beta-Lactamasas/genética , Mataderos , Animales , Antibacterianos/farmacología , Cefalosporinas/farmacología , Genes Bacterianos , Pruebas de Sensibilidad Microbiana , Fenotipo , República de Corea/epidemiología , Salmonella enteritidis/clasificación , Serogrupo
7.
Biochem Biophys Res Commun ; 432(1): 188-92, 2013 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-23313488

RESUMEN

Osx plays essential roles in regulating osteoblast and chondrocyte differentiation, and bone formation during mouse skeletal development. However, many questions remain regarding the requirement for Osx in different cell lineages. In this study, we asked whether Osx is required for craniofacial bone formation derived from cranial neural crest (CNC) cells. The Osx gene was conditionally inactivated in CNC-derived cells using a Wnt1-Cre recombination system. Neural crest-specific inactivation of Osx resulted in the complete absence of intramembranous skeletal elements derived from the CNC, and CNC-derived endochondral skeletal elements were also affected by Osx inactivation. Interestingly, Osx inactivated CNC-derived cells, which were recapitulated by lacZ expression, occupied the same regions of craniofacial skeletal elements as observed for controls. However, cells lost their osteogenic ability to differentiate into functional osteoblasts by Osx inactivation. These results suggest that Osx is important for craniofacial bone formation by CNC-derived cells. This finding provides novel insights of the regulation of craniofacial development by the gene network and transcription factors, and the understanding of human diseases caused by neural crest developmental abnormalities.


Asunto(s)
Anomalías Craneofaciales/genética , Huesos Faciales/embriología , Cresta Neural/anomalías , Osteogénesis/genética , Factores de Transcripción/fisiología , Animales , Anomalías Craneofaciales/patología , Huesos Faciales/anomalías , Huesos Faciales/patología , Silenciador del Gen , Integrasas/genética , Ratones , Ratones Transgénicos , Factor de Transcripción Sp7 , Factores de Transcripción/genética , Proteína Wnt1/genética
8.
PLoS One ; 18(6): e0287800, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37352213

RESUMEN

[This corrects the article DOI: 10.1371/journal.pone.0247655.].

9.
Microb Drug Resist ; 28(4): 492-497, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-35180355

RESUMEN

Global dissemination of mobilized colistin resistance (mcr)-1-carrying plasmids has been reported. This study aimed to investigate the global dissemination of these plasmids using whole genome sequencing to provide better understanding on genetic characteristics. Sixty-seven complete plasmid genomes harboring mcr-1 were obtained. Phylogeny was built against full plasmid genomes. Different replicon types of plasmid were compared in terms of antimicrobial resistance genes (ARGs), insertion sequence, and other functional genes. Five different replicon types of plasmid (IncX4, IncI2, IncP1, IncHIA, and IncFIB) were found to harbor mcr-1. IncX4 and IncI2 types of plasmid were well clustered in accordance with the country where they were isolated (and not as IncHIA and IncFIB). Three insertion sequences (ISApl1, ISKpn26, and IS1294) were identified in up- and/or downstream of mcr-1. Plasmids IncX4 and IncI2 were observed across the sample origin. Plasmids IncX4 showed high uniformity regardless of the origin of isolates and harbored H-NS coding genes, a facilitator for successful plasmid transfer. All three insertion sequences were observed in IncI2 plasmids. IncHI2 plasmids harbored various ARGs in addition to mcr-1. Our results elucidate the characteristics and phylogenetic relationships of complete mcr-1-harboring plasmids, indicating that global dissemination of mcr-1 is primarily owing to plasmid transfer rather than clonal spread.


Asunto(s)
Colistina , Proteínas de Escherichia coli , Antibacterianos/farmacología , Colistina/farmacología , Elementos Transponibles de ADN/genética , Farmacorresistencia Bacteriana/genética , Enterobacteriaceae , Escherichia coli , Proteínas de Escherichia coli/genética , Filogenia , Plásmidos/genética
10.
PLoS One ; 16(3): e0247655, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33735258

RESUMEN

Collective intelligence (CI) is the ability of a group to solve a wide range of problems. Synchrony in nonverbal cues is critically important to the development of CI; however, extant findings are mostly based on studies conducted face-to-face. Given how much collaboration takes place via the internet, does nonverbal synchrony still matter and can it be achieved when collaborators are physically separated? Here, we hypothesize and test the effect of nonverbal synchrony on CI that develops through visual and audio cues in physically-separated teammates. We show that, contrary to popular belief, the presence of visual cues surprisingly has no effect on CI; furthermore, teams without visual cues are more successful in synchronizing their vocal cues and speaking turns, and when they do so, they have higher CI. Our findings show that nonverbal synchrony is important in distributed collaboration and call into question the necessity of video support.


Asunto(s)
Procesos de Grupo , Inteligencia , Percepción Social/psicología , Habla/fisiología , Adolescente , Adulto , Señales (Psicología) , Expresión Facial , Femenino , Humanos , Internet , Masculino , Proyectos de Investigación , Comunicación por Videoconferencia/organización & administración
11.
Front Vet Sci ; 8: 650866, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34026890

RESUMEN

Feline parvovirus (FPV) is a small, non-enveloped, single-stranded DNA virus that infects cats. We recently isolated a feline parvovirus Fe-P2 strain from a dead stray cat in Iksan, 2017. Its partial genomic sequence (4,643 bases) was obtained, and phylogenetic analysis based on the VP2 nucleotide sequence showed that the FPV Fe-P2 strain was closely related to the FPV isolate Gigucheon in cat, 2017 (MN400978). In addition, we performed a serum neutralization (SN) test with the FPV isolates in various mammalian sera. These were from raccoon dog, water deer, Eurasian otter, Korean hare, leopard cat, and Asian badger, which were kindly provided by Chungnam Wild Animal Rescue Center. Notably, serological evidence of its infection was found in Asian badger, Meles leucurus (2/2) and leopard cat, Prionailurus bengalensis (5/8) through SN tests, whereas there was no evidence in raccoon dog, water deer, Eurasian otter, and Korean hare based on the collected sera in this study. These findings might provide partial evidence for the possible circulation of FPV or its related viruses among wild leopard cat and Asian badger in Korea. There should be additional study to confirm this through direct detection of FPVs in the related animal samples.

12.
Food Sci Biotechnol ; 29(10): 1433-1438, 2020 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-32999751

RESUMEN

This study aimed to investigate the influence of sodium reduction and storage temperature on the growth of total microbes and Bacillus cereus in naturally contaminated hamburger patty and loaf bread, respectively. The sodium reduction rate of hamburger patty and loaf bread was 20% and 30%, respectively, and experimental samples were kept at 4 °C, 25 °C, and 40 °C for 60 h. The microbiological analysis included the colony count of total microbes and B. cereus. The water activity (Aw), titratable acidity (TA), and pH were assessed as factors that inhibit microbial growth. In this study, Aw, TA, and pH of all samples were affected by the growth of total microbes and B. cereus during the storage period. Hence, these results suggested that sodium reduction in processed foods should be preferentially applied as a potent inhibition strategy after accurate assessment of inhibitors for different food types.

13.
Microbiol Resour Announc ; 9(7)2020 Feb 13.
Artículo en Inglés | MEDLINE | ID: mdl-32054707

RESUMEN

Cases of human infection with a swine influenza A virus variant have been reported in the United States, and since 2011, H3N2 variant viruses have also been regularly isolated from swine in the Republic of Korea. Here, we genetically characterized an influenza A H3N2 isolate (A/swine/P17-4/2017). BLASTN analysis of the 8 gene sequences revealed a high degree of nucleotide similarity (97.0 to 99.0%) to porcine strains circulating in the Republic of Korea and the United States. Specifically, we found a high degree of similarity in the nucleotide matrix gene to those of recent isolates from North Carolina. Therefore, continuous epidemiological surveillance is necessary to monitor the variation and evolution of influenza A viruses.

14.
J Clin Neurol ; 16(2): 261-269, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-32319243

RESUMEN

BACKGROUND AND PURPOSE: The first-line medications for the symptomatic treatment of rapid eye movement sleep behavior disorder (RBD) are clonazepam and melatonin taken at bedtime. We aimed to identify the association between depression and treatment response in patients with idiopathic RBD (iRBD). METHODS: We reviewed the medical records of 123 consecutive patients (76 males; age, 66.0±7.7 years; and symptom duration, 4.1±4.0 years) with iRBD who were treated with clonazepam and/or melatonin. Clonazepam and melatonin were initially administered at 0.25-0.50 and 2 mg/day, respectively, at bedtime, and the doses were subsequently titrated according to the response of individual patients. Treatment response was defined according to the presence or absence of any improvement in dream-enacting behaviors or unpleasant dreams after treatment. RESULTS: Forty (32.5%) patients were treated with clonazepam, 56 (45.5%) with melatonin, and 27 (22.0%) with combination therapy. The doses of clonazepam and melatonin at followup were 0.5±0.3 and 2.3±0.7 mg, respectively. Ninety-six (78.0%) patients reported improvement in their RBD symptoms during a mean follow-up period of 17.7 months. After adjusting for potential confounders, depression was significantly associated with a negative treatment response (odds ratio=3.76, 95% confidence interval=1.15-12.32, p=0.029). CONCLUSIONS: We found that comorbid depression is significantly associated with a negative response to clonazepam and/or melatonin in patients with iRBD. Further research with larger numbers of patients is needed to verify our observations and to determine the clinical implications of comorbid depression in the pathophysiology of iRBD.

15.
Front Psychol ; 10: 814, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31057455

RESUMEN

Management of effort is one of the biggest challenges in any team, and is particularly difficult in distributed teams, where behavior is relatively invisible to teammates. Awareness systems, which provide real-time visual feedback about team members' behavior, may serve as an effective intervention tool for mitigating various sources of process-loss in teams, including team effort. However, most of the research on visualization tools has been focusing on team communication and learning, and their impact on team effort and consequently team performance has been hardly studied. Furthermore, this line of research has rarely addressed the way visualization tool may interact with team composition, while comprehension of this interaction may facilitate a conceptualization of more effective interventions. In this article we review the research on feedback in distributed teams and integrate it with the research on awareness systems. Focusing on team effort, we examine the effect of an effort visualization tool on team performance in 72 geographically distributed virtual project teams. In addition, we test the moderating effect of team composition, specifically team members' conscientiousness, on the effectiveness of the effort visualization tool. Our findings demonstrate that the effort visualization tool increases team effort and improves the performance in teams with a low proportion of highly conscientious members, but not in teams with a high proportion of highly conscientious members. We discuss the theoretical and practical implications of our findings, and suggest the need of future research to address the way technological advances may contribute to management and research of team processes.

16.
Clin Pharmacol ; 11: 51-56, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30936756

RESUMEN

PURPOSE: The purpose of this study was to investigate the effects of the type of formulation on the efficacy of warfarin. MATERIALS AND METHODS: The electronic medical records of patients with cerebral infarction, who were administered tablet or powder formulations of warfarin from 2013-2015, were retrospectively analyzed. Clinical data, changes in the international normalized ratio (INR), the warfarin dose, and the time to reach the plasma warfarin concentration that could induce an adverse effect, such as bleeding, were evaluated. Coefficients of variation of INR and of the warfarin dose, as well as the warfarin sensitivity index (WSI), were used to evaluate the INR stability. Statistical analysis of the data was performed using a independent t-test. Additionally, survival analysis was performed. RESULTS: The data showed that 57 and 137 patients were administered warfarin as powder and tablet formulations, respectively. We noted that INR, WSI, and INR/dose × body weight differed significantly between the two groups of patients. The median survival times to reach the plasma warfarin concentration that could induce adverse effects were 3.6 and 4.2 days of treatment with the powder and tablet formulations, respectively. The efficacy of warfarin was higher when the drug was administered as a powder than when it was administered as a tablet. CONCLUSION: The findings of this study indicate that INR should be carefully monitored in the first 4 days of warfarin administration as a powder formulation.

17.
J Food Sci ; 84(1): 133-137, 2019 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-30557913

RESUMEN

The presence of unwanted competing flora has been the most common confounding factor in the enumeration of Bacillus cereus (B. cereus) using selective media such as mannitol-yolk-polymyxin B agar (MYPA). The objective of this study was to improve MYPA selectivity for B. cereus by supplementation with a second-generation cephalosporin, cefuroxime. The performance of cefuroxime-supplemented MYPA (cefu-MYPA) was evaluated by comparison with original MYPA in 60 food products with established microbiological standards for B. cereus contamination. Cefu-MYPA demonstrated superior recoverability and selectivity for B. cereus compared with original MYPA in most tested foods. B. cereus numbers on MYPA and cefu-MYPA were 363.5 and 462.0 CFU/g, respectively. Competing flora on cefu-MYPA was detected in significantly less samples (70%) compared to original MYPA (93%). In addition, the detection and isolation of suspected colonies were significantly improved in cefu-MYPA because of the reduction or elimination of competing flora in all tested foods except fruit juice, indicating superior selectivity of the modified medium. Our findings suggest that cefuroxime supplementation of MYPA would markedly improve the detection rate of B. cereus, particularly in foods with high levels of indigenous flora.


Asunto(s)
Bacillus cereus/aislamiento & purificación , Cefuroxima/química , Medios de Cultivo/química , Yema de Huevo/química , Contaminación de Alimentos/análisis , Manitol/química , Agar/química , Recuento de Colonia Microbiana , Microbiología de Alimentos , Pruebas de Sensibilidad Microbiana , Polimixina B/química
18.
J Microbiol Biotechnol ; 18(4): 639-47, 2008 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-18467855

RESUMEN

The heat-inducible expression vectors for Corynebacterium glutamicum and C. ammoniagenes were constructed by using the lambdaOL1 and the cryptic promoters, CJ1 and CJ4 that express genes constitutively in C. ammoniagenes.. Although the promoters were isolated from C. ammoniagenes, CJ1 and CJ4 were also active in C. glutamicum. To construct vectors, the OL1 from the lambdaPL promoter was isolated and fused to the CJ1 and CJ4 promoters by recombinant PCR. The resulting artificial promoters, CJ1O and CJ4O, which have one lambdaOL1, and CJ1OX2, which has two successive lambdaOL1, were fused to the green fluorescent protein (GFP) gene followed by subcloning into pCES208. The expression of GFP in the corynebacteria harboring the vectors was regulated successfully by the temperature sensitive cI857 repressor. Among them, C. ammoniagenes harboring plasmid pCJ1OX2G containing GFP fused to CJ1OX2 showed more GFP than the other ones and the expression was tightly regulated by the repressor. To construct the generally applicable expression vector using the plasmid pCJ1OX2G, the His-tag, enterokinase (EK) moiety, and the MCS were inserted in front of the GFP gene. Using the vector, the expression of pyrR from C. glutamicum was tried by temperature shift-up. The results indicated that the constructed vectors (pCeHEMG) can be successfully used in the expression and regulation of foreign genes in corynebacteria.


Asunto(s)
Bacteriófago lambda/genética , Corynebacterium/genética , Ingeniería Genética , Vectores Genéticos/genética , Regiones Operadoras Genéticas , Regiones Promotoras Genéticas , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Secuencia de Bases , Clonación Molecular , Corynebacterium/metabolismo , Expresión Génica , Genes Reporteros , Proteínas Fluorescentes Verdes/genética , Proteínas Fluorescentes Verdes/metabolismo , Calor , Datos de Secuencia Molecular , Proteínas Represoras/genética , Proteínas Represoras/metabolismo
19.
Int J Hyg Environ Health ; 221(2): 300-307, 2018 03.
Artículo en Inglés | MEDLINE | ID: mdl-29254843

RESUMEN

Although the prevalence of community-acquired Stenotrophomonas maltophilia infections is sharply increasing, the sources and likely transmission routes of this bacterium are poorly understood. We studied the significance of the presence of S. maltophilia in final effluents and receiving rivers of pig farm wastewater treatment plants (WWTPs). The loads and antibiotic resistance profiles of S. maltophilia in final effluents were assessed. Antibiotic resistance determinants and biofilm formation genes were detected by PCR, and genetic similarity to clinical isolates was investigated using multilocus sequence typing (MLST). S. maltophilia was recovered from final effluents at two of three farms and one corresponding receiving river. Tests of resistance to antibiotics recommended for S. maltophilia infection revealed that for each agent, at least one isolate was classified as resistant or intermediate, with the exception of minocycline. Furthermore, multidrug resistant S. maltophilia susceptible to antibiotics of only two categories was isolated and found to carry the sul2 gene, conferring trimethoprim/sulfamethoxazole resistance. All isolates carried spgM, encoding a major factor in biofilm formation. MLST revealed that isolates of the same sequence type (ST; ST189) were present in both effluent and receiving river samples, and phylogenetic analysis showed that all of the STs identified in this study clustered with clinical isolates. Moreover, one isolate (ST192) recovered in this investigation demonstrated 99.61% sequence identity with a clinical isolate (ST98) associated with a fatal infection in South Korea. Thus, the pathogenicity of the isolates reported here is likely similar to that of those from clinical environments, and WWTPs may play a role as a source of S. maltophilia from which this bacterium spreads to human communities. To the best of our knowledge, this represents the first report of S. maltophilia in pig farm WWTPs. Our results indicate that nationwide epidemiological investigations are needed to examine the possible link between WWTP-derived S. maltophilia and hospital- and community-acquired infections.


Asunto(s)
Infecciones Comunitarias Adquiridas/epidemiología , Infecciones por Bacterias Gramnegativas/epidemiología , Stenotrophomonas maltophilia/genética , Porcinos , Aguas Residuales/microbiología , Animales , Infecciones Comunitarias Adquiridas/microbiología , Farmacorresistencia Bacteriana/genética , Granjas , Infecciones por Bacterias Gramnegativas/microbiología , Humanos , Pruebas de Sensibilidad Microbiana , Ríos/microbiología , Stenotrophomonas maltophilia/aislamiento & purificación , Administración de Residuos , Purificación del Agua
20.
PLoS One ; 13(10): e0204547, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30304044

RESUMEN

Today, many complex tasks are assigned to teams, rather than individuals. One reason for teaming up is expansion of the skill coverage of each individual to the joint team skill set. However, numerous empirical studies of human groups suggest that the performance of equally skilled teams can widely differ. Two natural question arise: What are the factors defining team performance? and How can we best predict the performance of a given team on a specific task? While the team members' task-related capabilities constrain the potential for the team's success, the key to understanding team performance is in the analysis of the team process, encompassing the behaviors of the team members during task completion. In this study, we extend the existing body of research on team process and prediction models of team performance. Specifically, we analyze the dynamics of historical team performance over a series of tasks as well as the fine-grained patterns of collaboration between team members, and formally connect these dynamics to the team performance in the predictive models. Our major qualitative finding is that higher performing teams have well-connected collaboration networks-as indicated by the topological and spectral properties of the latter-which are more robust to perturbations, and where network processes spread more efficiently. Our major quantitative finding is that our predictive models deliver accurate team performance predictions-with a prediction error of 15-25%-on a variety of simple tasks, outperforming baseline models that do not capture the micro-level dynamics of team member behaviors. We also show how to use our models in an application, for optimal online planning of workload distribution in an organization. Our findings emphasize the importance of studying the dynamics of team collaboration as the major driver of high performance in teams.


Asunto(s)
Conducta Cooperativa , Procesos de Grupo , Modelos Psicológicos , Humanos , Procesos Mentales , Análisis de Regresión
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