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1.
Antimicrob Agents Chemother ; 67(10): e0034923, 2023 10 18.
Artículo en Inglés | MEDLINE | ID: mdl-37728368

RESUMEN

We have previously reported on the susceptibility and epidemiology of Clostridioides difficile isolates from six geographically dispersed medical centers in the United States. This current survey was conducted with isolates collected in 2020-2021 from six geographically dispersed medical centers in the United States, with specific attention to susceptibility to ridinilazole as well as nine comparators. C. difficile isolates or stools from patients with C. difficile antibiotic-associated diarrhea were collected and referred to a central laboratory. After species confirmation of 300 isolates at the central laboratory, antibiotic susceptibilities were determined by the agar dilution method [M11-A9, Clinical and Laboratory Standards Institute (CLSI)] against the 10 agents. Ribotyping was performed by PCR capillary gel electrophoresis on all isolates. Ridinilazole had a minimum inhibitory concentration (MIC) 90 of 0.25 mcg/mL, and no isolate had an MIC greater than 0.5 mcg/mL. In comparison, fidaxomicin had an MIC 90 of 0.5 mcg/mL. The vancomycin MIC 90 was 2 mcg/mL with a 0.7% resistance rate [both CLSI and European Committee on Antimicrobial Susceptibility Testing (EUCAST) criteria]. The metronidazole MIC 90 was 1 mcg/mL, with none resistant by CLSI criteria, and a 0.3% resistance rate by EUCAST criteria. Among the 50 different ribotypes isolated in the survey, the most common ribotype was 014-020 (14.0%) followed by 106 (10.3%), 027 (10%), 002 (8%), and 078-126 (4.3%). Ridinilazole maintained activity against all ribotypes and all strains resistant to any other agent tested. Ridinilazole showed excellent in vitro activity against C. difficile isolates collected between 2020 and 2021 in the United States, independent of ribotype.


Asunto(s)
Clostridioides difficile , Infecciones por Clostridium , Humanos , Antibacterianos/farmacología , Antibacterianos/uso terapéutico , Clostridioides difficile/genética , Clostridioides , Infecciones por Clostridium/tratamiento farmacológico , Infecciones por Clostridium/epidemiología , Pruebas de Sensibilidad Microbiana , Ribotipificación
2.
Epidemiol Infect ; 149: e108, 2021 04 19.
Artículo en Inglés | MEDLINE | ID: mdl-33866980

RESUMEN

Recurrent outbreaks of haemolytic uraemic syndrome (HUS) caused by Shiga toxin-producing Escherichia coli (STEC) serotype O55:H7 occurred in England between 2014 and 2018. We reviewed the epidemiological evidence to identify potential source(s) and transmission routes of the pathogen, and to assess the on-going risk to public health. Over the 5-year period, there were 43 confirmed and three probable cases of STEC O55:H7. The median age of cases was 4 years old (range 6 months to 69 years old) and over half of all cases were female (28/46, 61%). There were 36/46 (78.3%) symptomatic cases, and over half of all cases developed HUS (25/46, 54%), including two fatal cases. No common food or environmental exposures were identified, although the majority of cases lived in rural or semi-rural environments and reported contact with both wild and domestic animals. This investigation informed policy on the clinical and public health management of HUS caused by STEC other than serotype O157:H7 (non-O157 STEC) in England, including comprehensive testing of all household contacts and household pets and more widespread use of polymerase chain reaction assays for the rapid diagnosis of STEC-HUS.


Asunto(s)
Brotes de Enfermedades/estadística & datos numéricos , Infecciones por Escherichia coli/epidemiología , Síndrome Hemolítico-Urémico/epidemiología , Escherichia coli Shiga-Toxigénica/patogenicidad , Adolescente , Adulto , Anciano , Animales , Niño , Preescolar , Inglaterra/epidemiología , Infecciones por Escherichia coli/microbiología , Infecciones por Escherichia coli/transmisión , Femenino , Síndrome Hemolítico-Urémico/microbiología , Humanos , Lactante , Masculino , Persona de Mediana Edad , Filogenia , Factores de Riesgo , Serogrupo , Escherichia coli Shiga-Toxigénica/clasificación , Escherichia coli Shiga-Toxigénica/genética , Adulto Joven
3.
Eur J Public Health ; 31(3): 576-582, 2021 07 13.
Artículo en Inglés | MEDLINE | ID: mdl-33411922

RESUMEN

BACKGROUND: The implementation by diagnostic laboratories in England of polymerase chain reaction (PCR) to screen faecal specimens for Shiga toxin-producing Escherichia coli (STEC) has resulted in a significant increase in notifications mainly due to non-O157 strains. The purpose of this study was to develop an approach to public health risk assessment that prioritizes follow-up to cases caused by haemolytic uraemic syndrome (HUS) associated E. coli (HUSEC) strains and minimizes unnecessary actions. METHODS: Epidemiological and microbiological data were prospectively collected from 1 November 2013 to 31 March 2017 and used to compare three risk assessment approaches. RESULTS: A history of HUS/bloody diarrhoea/age under 6 years and faecal specimens positive for stx-predicted HUSEC with a diagnostic accuracy of 84% (95% CI; 81-88%). STEC isolated by Gastrointestinal Bacteria Reference Unit (GBRU) and stx2 and eae positive predicted HUSEC with a diagnostic accuracy of 99% (95% CI; 98-100%). Risk assessment combining these two tests predicts the most efficient use of resources, predicting that 18% (97/552) of cases would be eligible for follow-up at some stage, 16% (86/552) following local stx PCR results, 1% (7/552) following GBRU results of stx2 and eae status and 0.7% (4/552) following whole-genome sequencing. Follow-up could be stopped in 78% (76/97) of these cases, 97% (74/76) following second stage risk assessment. CONCLUSIONS: This three-stage risk assessment approach prioritizes follow-up to HUSEC and minimizes unnecessary public health actions. We developed it into the algorithm for public health actions included in the updated PHE Guidance for management of STEC published in August 2018.


Asunto(s)
Infecciones por Escherichia coli , Síndrome Hemolítico-Urémico , Escherichia coli Shiga-Toxigénica , Niño , Infecciones por Escherichia coli/diagnóstico , Infecciones por Escherichia coli/epidemiología , Síndrome Hemolítico-Urémico/diagnóstico , Síndrome Hemolítico-Urémico/epidemiología , Humanos , Reacción en Cadena de la Polimerasa , Salud Pública , Escherichia coli Shiga-Toxigénica/genética
5.
Pediatr Allergy Immunol ; 29(2): 144-150, 2018 03.
Artículo en Inglés | MEDLINE | ID: mdl-29168294

RESUMEN

BACKGROUND: Prenatal folic acid supplementation is recommended to prevent birth defects. Some foods are fortified in the USA to ensure sufficient intake among reproductive-aged women. However, high prenatal folate exposure may be a risk factor for childhood atopic diseases. We investigated associations between prenatal folate and early childhood wheeze and atopic dermatitis in a US cohort. METHODS: We studied 858 mother-child dyads, enrolled prenatally. Folate was measured in 2nd and 3rd trimester maternal plasma. Parents reported current wheeze (previous 12 months) and healthcare provider diagnosis of atopic dermatitis at 3 years. We examined associations using logistic regression, modeling folate continuously and dichotomously (< or ≥20 ng/mL), a level often considered supraphysiologic. RESULTS: Over half of women were African American and on Medicaid. Median (interquartile range) folate levels were 22.6 (15.9-30.0) and 23.1 (16.1-30.0) ng/mL for 2nd and 3rd trimesters, respectively. Current wheeze and atopic dermatitis were reported for 20.4% and 26.8% of children, respectively. Second trimester folate as a continuous exposure was not significantly associated with outcomes. Decreased odds of current wheeze were observed in children born to mothers who had 2nd trimester folate ≥20 ng/mL (adjusted odds ratios = 0.67, 95% confidence interval = 0.46, 0.97) compared to children with maternal levels <20 ng/mL. Third trimester folate was not associated with outcomes. CONCLUSIONS: High plasma folate in mid-pregnancy was associated with decreased odds of current wheeze at age 3. Our findings do not support harmful effects of high prenatal folate levels on childhood atopic diseases in this setting.


Asunto(s)
Dermatitis Atópica/etiología , Ácido Fólico/efectos adversos , Ruidos Respiratorios/etiología , Adolescente , Adulto , Preescolar , Dermatitis Atópica/epidemiología , Femenino , Ácido Fólico/sangre , Humanos , Masculino , Embarazo , Efectos Tardíos de la Exposición Prenatal/epidemiología , Estudios Prospectivos , Factores de Riesgo , Estados Unidos , Adulto Joven
6.
Nanotechnology ; 27(31): 315302, 2016 Aug 05.
Artículo en Inglés | MEDLINE | ID: mdl-27344982

RESUMEN

Patterning nanoscale protein gradients is crucial for studying a variety of cellular processes in vitro. Despite the recent development in nano-fabrication technology, combining nanometric resolution and fine control of protein concentrations is still an open challenge. Here, we demonstrate the use of thermochemical scanning probe lithography (tc-SPL) for defining micro- and nano-sized patterns with precisely controlled protein concentration. First, tc-SPL is performed by scanning a heatable atomic force microscopy tip on a polymeric substrate, for locally exposing reactive amino groups on the surface, then the substrate is functionalized with streptavidin and laminin proteins. We show, by fluorescence microscopy on the patterned gradients, that it is possible to precisely tune the concentration of the immobilized proteins by varying the patterning parameters during tc-SPL. This paves the way to the use of tc-SPL for defining protein gradients at the nanoscale, to be used as chemical cues e.g. for studying and regulating cellular processes in vitro.

7.
Andrologia ; 48(7): 774-8, 2016 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-26688574

RESUMEN

Male attitude about masturbation may influence early diagnosis and treatment of infertility and may be of particular burden in developing countries. We sought to explore attitude about masturbating and examine comfort/discomfort with masturbating and sexual history, pregnancy history and sperm quality in men investigating fertility potential. The study consisted of 83 male volunteers, 23-61 years, attending a fertility management unit in Kingston, Jamaica. Comfort with masturbation was assessed by a self-administered questionnaire. Participants also completed the unit's standard intake form for infertility investigations and produced a semen sample. T-tests, Mann-Whitney U-test and chi-square were used to compare differences in comfort level with outcome variables. We found 59% were comfortable masturbating although requiring external stimulation to produce a sample (48%); 6% (n = 5) failed to produce a sample after repeated attempts. A higher percentage of men uncomfortable with masturbating reported sexual problems (P < 0.05) and spending a longer time trying to have a baby (P < 0.05). Semen quality was not associated with masturbating comfort. Producing a sample by masturbation is standard for many assisted conception treatments. As comfort with masturbating may influence delay in infertility investigations and fertility outcome, efforts to improve men's comfort level with semen production should be considered in pre-treatment fertility counselling.


Asunto(s)
Actitud , Infertilidad Masculina/diagnóstico , Masturbación/psicología , Análisis de Semen/psicología , Adulto , Voluntarios Sanos , Humanos , Jamaica , Masculino , Persona de Mediana Edad , Historia Reproductiva , Encuestas y Cuestionarios , Adulto Joven
8.
Cleft Palate Craniofac J ; 53(5): 539-49, 2016 09.
Artículo en Inglés | MEDLINE | ID: mdl-26171570

RESUMEN

Nonsyndromic orofacial clefting (OFC) describes a range of phenotypes that represent the most common craniofacial birth defects in humans, with an overall birth prevalence of 1:700 live births. Because of the lifelong negative implications on health and well-being associated with OFC and the numbers of people affected, quality research into its etiology, diagnosis, treatment outcomes, and preventative strategies is essential. A range of different methods is used for recording and classifying OFC subphenotypes, one of which is the International Classification of Diseases (ICD) system. However, there is a general perception that research is being hampered by a lack of sensitivity and specificity in grouping those with OFC into subphenotypes, with potential heterogeneity and confounding in epidemiologic, genetic, and genotype-phenotype correlation studies. This article provides a background to the necessity of OFC research, discusses current controversies within cleft subphenotyping, and provides a brief overview of current OFC classifications as well as their limitations. The LAHSHAL classification is described in the context of a potentially useful tool for OFC that could complement the ICD-10/ICD-11 Beta coding systems to become a simply understood, universally accepted, clinically friendly, and research-sensitive instrument. Empowering registries, clinicians, and researchers to use a common classification system would have significant implications for OFC research across the world at a time when accurate subphenotyping is crucial and health care research is becoming increasingly tailored toward the individual.


Asunto(s)
Labio Leporino/clasificación , Fisura del Paladar/clasificación , Fenotipo , Humanos , Clasificación Internacional de Enfermedades , Prevalencia , Sistema de Registros
9.
Eur J Clin Microbiol Infect Dis ; 34(9): 1871-7, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-26173688

RESUMEN

Bacteroides fragilis is a common colonic symbiote of which one subtype, enterotoxigenic Bacteroides fragilis (ETBF), causes inflammatory diarrhea. However, asymptomatic ETBF colonization is common. Through its primary virulence factor, B. fragilis toxin (BFT), ETBF causes asymptomatic, chronic colitis in C57BL/6 mice and increased colon tumorigenesis in multiple intestinal neoplasia mice. Human studies suggest an association between ETBF infection, inflammatory bowel disease, and colon cancer. Additional studies on ETBF epidemiology are, therefore, crucial. The goal of this study is to develop a reliable fecal diagnostic for ETBF. To develop a sensitive assay for ETBF, we tested multiple protocols on mouse stools spiked with serially diluted ETBF. Each assay was based on either touchdown or quantitative polymerase chain reaction (qPCR) and used primers targeted to bft to detect ETBF. Using touchdown PCR or qPCR, the mean ETBF detection limit was 1.55 × 10(6) colony-forming units (CFU)/g stool and 1.33 × 10(4) CFU/g stool, respectively. Augmentation of Bacteroides spp. growth in fecal samples using PYGB (Peptone Yeast Glucose with Bile) broth enhanced ETBF detection to 2.93 × 10(2) CFU/g stool using the touchdown PCR method and 2.63 × 10(2) CFU/g stool using the qPCR method. Fecal testing using combined culture-based amplification and bft touchdown PCR is a sensitive assay for the detection of ETBF colonization and should be useful in studying the role of ETBF colonization in intestinal diseases, such as inflammatory bowel disease and colon cancer. We conclude that touchdown PCR with culture-based amplification may be the optimal ETBF detection strategy, as it performs as well as qPCR with culture-based amplification, but is a less expensive technique.


Asunto(s)
Toxinas Bacterianas/metabolismo , Infecciones por Bacteroides/diagnóstico , Bacteroides fragilis/aislamiento & purificación , Enterotoxinas/metabolismo , Heces/microbiología , Animales , Infecciones por Bacteroides/microbiología , Bacteroides fragilis/patogenicidad , Colitis/microbiología , Enterocolitis/microbiología , Neoplasias Gastrointestinales/microbiología , Ratones , Ratones Endogámicos C57BL
10.
J Clin Microbiol ; 52(11): 3928-32, 2014 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-25165083

RESUMEN

Sepsis caused by Staphylococcus aureus is a major health problem worldwide. Better outcomes are achieved when rapid diagnosis and determination of methicillin susceptibility enable early optimization of antimicrobial therapy. Eight large clinical laboratories, seven from the United States and one from Scotland, evaluated the combination of the Staphylococcus QuickFISH BC and the new mecA XpressFISH assay (both AdvanDx, Woburn, MA, USA) for the detection of methicillin-resistant S. aureus in positive blood cultures. Blood cultures flagged as positive by automated blood culture instruments and demonstrating only Gram-positive cocci in clusters on Gram stain were tested by QuickFISH, a 20-min assay. If only S. aureus was detected, mecA XpressFISH testing followed. The recovered S. aureus isolates were tested by cefoxitin disk diffusion as the reference method. The QuickFISH assay results were concordant with the routine phenotypic testing methods of the testing laboratories in 1,211/1,221 (99.1%) samples and detected 488/491 S. aureus organisms (sensitivity, 99.4%; specificity, 99.6%). Approximately 60% of the samples (730) contained coagulase-negative staphylococci or nonstaphylococci as assessed by the QuickFISH assay and were not tested further. The 458 compliant samples positive exclusively for S. aureus by the QuickFISH assay were tested by the mecA XpressFISH assay, which detected 209 of 211 methicillin-resistant S. aureus organisms (sensitivity, 99.1%; specificity, 99.6%). The mecA XpressFISH assay also showed high reproducibility, with 534/540 tests performed by 6 operators over 5 days achieving reproducible results (98.9% agreement). The combination of the Staphylococcus QuickFISH BC and mecA XpressFISH assays is sensitive, specific, and reproducible for the detection of methicillin-resistant S. aureus and yields complete results in 2 h after the blood culture turns positive.


Asunto(s)
Sangre/microbiología , Hibridación Fluorescente in Situ/métodos , Staphylococcus aureus Resistente a Meticilina/aislamiento & purificación , Técnicas de Diagnóstico Molecular/métodos , Sepsis/diagnóstico , Infecciones Estafilocócicas/diagnóstico , Infecciones Estafilocócicas/microbiología , Técnicas Bacteriológicas/métodos , Humanos , Staphylococcus aureus Resistente a Meticilina/genética , Reproducibilidad de los Resultados , Escocia , Sensibilidad y Especificidad , Sepsis/microbiología , Estados Unidos
11.
J Appl Microbiol ; 116(4): 934-41, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24410849

RESUMEN

AIMS: (i) Evaluation of delayed time to blood culture extraction by the Sepsityper kit and impact of shipping pellets off-site for MALDI-TOF MS analysis. (ii) Comparison of Sepsityper and laboratory-developed extraction methods from a literature review. METHODS AND RESULTS: Using two blood culture systems (BD BACTEC and VersaTREK), we extracted 411 positive blood cultures using the Sepsityper kit to mimic a potential protocol for institutions without a MALDI-TOF MS. Extracted pellets were shipped and analysed on the Bruker UltraflexIII. Successful extraction of 358 (87·1%) samples was determined by the presence of detectable proteins. MALDI-TOF MS correctly identified 332 (80·8%) samples. CONCLUSIONS: Delayed time to extraction did not affect Sepsityper extraction or MALDI-TOF MS accuracy. The extracted pellets remain stable and provide accurate results by MALDI-TOF MS when shipped at room temperature to off-site reference laboratories. SIGNIFICANCE AND IMPACT OF THE STUDY: This is the first study to show that institutions without a MALDI-TOF MS can take advantage of this innovative technology by shipping a volume of blood to an off-site laboratory for extraction and MALDI-TOF MS analysis. We also performed a literature review to compare various extraction methods.


Asunto(s)
Bacterias/aislamiento & purificación , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción/métodos , Bacteriemia/diagnóstico , Proteínas Bacterianas/análisis , Proteínas Bacterianas/aislamiento & purificación , Técnicas Bacteriológicas/métodos , Humanos
12.
Ground Water Monit Remediat ; 34(4): 23-32, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-26069436

RESUMEN

The objective of this study was to characterize the behavior of a groundwater contaminant (trichloroethene) plume after implementation of a source-containment operation at a site in Arizona. The plume resides in a quasi three-layer system comprising a sand/gravel unit bounded on the top and bottom by relatively thick silty clayey layers. The system was monitored for 60 months beginning at start-up in 2007 to measure the change in contaminant concentrations within the plume, the change in plume area, the mass of contaminant removed, and the integrated contaminant mass discharge. Concentrations of trichloroethene in groundwater pumped from the plume extraction wells have declined significantly over the course of operation, as have concentrations for groundwater sampled from 40 monitoring wells located within the plume. The total contaminant mass discharge associated with operation of the plume extraction wells peaked at 0.23 kg/d, decreased significantly within one year, and thereafter began an asymptotic decline to a current value of approximately 0.03 kg/d. Despite an 87% reduction in contaminant mass and a comparable 87% reduction in contaminant mass discharge for the plume, the spatial area encompassed by the plume has decreased by only approximately 50%. This is much less than would be anticipated based on ideal flushing and mass-removal behavior. Simulations produced with a simplified 3-D numerical model matched reasonably well to the measured data. The results of the study suggest that permeability heterogeneity, back diffusion, hydraulic factors associated with the specific well field system, and residual discharge from the source zone are all contributing to the observed persistence of the plume, as well as the asymptotic behavior currently observed for mass removal and for the reduction in contaminant mass discharge.

13.
Gait Posture ; 111: 30-36, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38615566

RESUMEN

BACKGROUND: Approaches to gait analysis are evolving rapidly and now include a wide range of options: from e-patches to video platforms to wearable inertial measurement unit systems. Newer options for gait analysis are generally more inclusive for the assessment of children, more cost effective and easier to administer. However, there is limited data on the comparability of newer systems with more established traditional approaches in young children. RESEARCH QUESTION: To determine comparability between the Physilog®5 wearable inertial sensor and GAITRite® electronic walkway for spatiotemporal (stride length, time and velocity, cadence) and relative phase (double support time, stance, swing, loading, foot flat and push off) data in young children. METHODS: A total 34 typically developing participants (41% female) aged 6-11 years old median age 8.99 years old (interquartile range 2.83) were assessed walking at self-selected speed over the GAITRite® electronic walkway while concurrently wearing shoe-attached Physilog®5 IMU sensors. Level of agreement was analysed by Lin's concordance correlation coefficient (CCC), Bland-Altman plots and 95% limit of agreement. Systematic bias was assessed using 95% confidence interval of the mean difference. RESULTS: Excellent to almost perfect agreement was observed between systems for spatiotemporal metrics: cadence (CCC=0.996), stride length (CCC=0.993), stride time (CCC=0.996), stride velocity (CCC=0.988). The relative phase metrics adjusted for stride velocity showed improved comparability when compared to the unadjusted metrics: swing adjusted (adj) (CCC=0.635); stance adj (CCC: 0.879); loading adj: (CCC=0.626). SIGNIFICANCE: Spatiotemporal metrics are highly compatible across GAITRite® electronic walkway and Physilog®5 IMU systems in young children. Relative phase metrics were somewhat compatible between systems when adjusted for stride velocity.


Asunto(s)
Análisis de la Marcha , Dispositivos Electrónicos Vestibles , Humanos , Niño , Femenino , Masculino , Análisis de la Marcha/instrumentación , Acelerometría/instrumentación , Fenómenos Biomecánicos , Caminata/fisiología , Marcha/fisiología , Análisis Espacio-Temporal
14.
J Clin Microbiol ; 50(10): 3301-8, 2012 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-22855510

RESUMEN

Matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) has been found to be an accurate, rapid, and inexpensive method for the identification of bacteria and yeasts. Previous evaluations have compared the accuracy, time to identification, and costs of the MALDI-TOF MS method against standard identification systems or commercial panels. In this prospective study, we compared a protocol incorporating MALDI-TOF MS (MALDI protocol) with the current standard identification protocols (standard protocol) to determine the performance in actual practice using a specimen-based, bench-by-bench approach. The potential impact on time to identification (TTI) and costs had MALDI-TOF MS been the first-line identification method was quantitated. The MALDI protocol includes supplementary tests, notably for Streptococcus pneumoniae and Shigella, and indications for repeat MALDI-TOF MS attempts, often not measured in previous studies. A total of 952 isolates (824 bacterial isolates and 128 yeast isolates) recovered from 2,214 specimens were assessed using the MALDI protocol. Compared with standard protocols, the MALDI protocol provided identifications 1.45 days earlier on average (P < 0.001). In our laboratory, we anticipate that the incorporation of the MALDI protocol can reduce reagent and labor costs of identification by $102,424 or 56.9% within 12 months. The model included the fixed annual costs of the MALDI-TOF MS, such as the cost of protein standards and instrument maintenance, and the annual prevalence of organisms encountered in our laboratory. This comprehensive cost analysis model can be generalized to other moderate- to high-volume laboratories.


Asunto(s)
Bacterias/aislamiento & purificación , Infecciones Bacterianas/diagnóstico , Hongos/aislamiento & purificación , Técnicas Microbiológicas/métodos , Técnicas de Diagnóstico Molecular/métodos , Micosis/diagnóstico , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción/métodos , Bacterias/química , Bacterias/clasificación , Infecciones Bacterianas/microbiología , Análisis Costo-Beneficio , Hongos/química , Hongos/clasificación , Humanos , Técnicas Microbiológicas/economía , Técnicas de Diagnóstico Molecular/economía , Micosis/microbiología , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción/economía , Factores de Tiempo
15.
Epidemiol Infect ; 140(8): 1400-13, 2012 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-22093751

RESUMEN

In the summer of 2009, an outbreak of verocytotoxigenic Escherichia coli O157 (VTEC O157) was identified in visitors to a large petting farm in South East England. The peak attack rate was 6/1000 visitors, and highest in those aged <2 years (16/1000). We conducted a case-control study with associated microbiological investigations, on human, animal and environmental samples. We identified 93 cases; 65 primary, 13 secondary and 15 asymptomatic. Cases were more likely to have visited a specific barn, stayed for prolonged periods and be infrequent farm visitors. The causative organism was identified as VTEC O157 PT21/28 with the same VNTR profile as that isolated in faecal specimens from farm animals and the physical environment, mostly in the same barn. Contact with farm livestock, especially ruminants, should be urgently reviewed at the earliest suspicion of a farm-related VTEC O157 outbreak and appropriate risk management procedures implemented without delay.


Asunto(s)
Brotes de Enfermedades , Infecciones por Escherichia coli/epidemiología , Infecciones por Escherichia coli/microbiología , Escherichia coli O157/metabolismo , Toxinas Shiga/metabolismo , Animales , Estudios de Casos y Controles , Preescolar , Recolección de Datos , Inglaterra/epidemiología , Infecciones por Escherichia coli/transmisión , Femenino , Humanos , Lactante , Modelos Logísticos , Masculino , Factores de Riesgo , Encuestas y Cuestionarios , Factores de Tiempo , Zoonosis
16.
Proc Natl Acad Sci U S A ; 106(28): 11594-9, 2009 Jul 14.
Artículo en Inglés | MEDLINE | ID: mdl-19553217

RESUMEN

Many cell-cell adhesive events are mediated by the dimerization of cadherin proteins presented on apposing cell surfaces. Cadherin-mediated processes play a central role in the sorting of cells into separate tissues in vivo, but in vitro assays aimed at mimicking this behavior have yielded inconclusive results. In some cases, cells that express different cadherins exhibit homotypic cell sorting, forming separate cell aggregates, whereas in other cases, intermixed aggregates are formed. A third pattern is observed for mixtures of cells expressing either N- or E-cadherin, which form distinct homotypic aggregates that adhere to one another through a heterotypic interface. The molecular basis of cadherin-mediated cell patterning phenomena is poorly understood, in part because the relationship between cellular adhesive specificity and intermolecular binding free energies has not been established. To clarify this issue, we have measured the dimerization affinities of N-cadherin and E-cadherin. These proteins are similar in sequence and structure, yet are able to mediate homotypic cell patterning behavior in a variety of tissues. N-cadherin is found to form homodimers with higher affinity than does E-cadherin and, unexpectedly, the N/E-cadherin heterophilic binding affinity is intermediate in strength between the 2 homophilic affinities. We can account for observed cell aggregation behaviors by using a theoretical framework that establishes a connection between molecular affinities and cell-cell adhesive specificity. Our results illustrate how graded differences between different homophilic and heterophilic cadherin dimerizaton affinities can result in homotypic cell patterning and, more generally, show how proteins that are closely related can, nevertheless, be responsible for highly specific cellular adhesive behavior.


Asunto(s)
Cadherinas/metabolismo , Adhesión Celular/fisiología , Dimerización , Modelos Moleculares , Unión Proteica , Animales , Área Bajo la Curva , Células CHO , Cadherinas/química , Agregación Celular/fisiología , Cricetinae , Cricetulus
17.
Environ Geochem Health ; 34(4): 539-50, 2012 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-21947714

RESUMEN

Sulfate is ubiquitous in groundwater, with both natural and anthropogenic sources. Sulfate reduction reactions play a significant role in mediating redox conditions and biogeochemical processes for subsurface systems. They also serve as the basis for innovative in situ methods for groundwater remediation. An overview of sulfate reduction in subsurface environments is provided, along with a brief discussion of characterization methods and applications for addressing acid mine drainage. We then focus on two innovative, in situ methods for remediating sulfate-contaminated groundwater, the use of zero-valent iron and the addition of electron-donor substrates. The advantages and limitations associated with the methods are discussed, with examples of prior applications.


Asunto(s)
Restauración y Remediación Ambiental/métodos , Agua Subterránea/química , Sulfatos/metabolismo , Contaminantes Químicos del Agua/metabolismo , Hierro/metabolismo , Minería , Oxidación-Reducción , Sulfatos/química , Contaminantes Químicos del Agua/química
18.
West Indian Med J ; 61(2): 145-7, 2012 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-23155959

RESUMEN

Staphylococcus aureus is an important pathogen in both community and healthcare associated pneumonia. We describe a case of severe pneumonia caused by the methicillin resistant Staphylococcus aureus (MRSA) clone USA 300 in a 44-year old post-partum woman and the subsequent vertical transmission of this virulent organism to her neonate.


Asunto(s)
Transmisión Vertical de Enfermedad Infecciosa , Staphylococcus aureus Resistente a Meticilina , Neumonía Estafilocócica/transmisión , Infección Puerperal , Adulto , Femenino , Genotipo , Humanos , Recién Nacido , Masculino , Staphylococcus aureus Resistente a Meticilina/genética , Neumonía Estafilocócica/microbiología , Embarazo , Infecciones Estafilocócicas/transmisión
19.
Gait Posture ; 91: 19-25, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-34628218

RESUMEN

BACKGROUND: Gait Up Physilog® wearable inertial sensors are a powerful alternative to traditional laboratory-based gait assessment for children with gait impairment. To build clinician trust in these devices and ultimately facilitate their use outside confined spaces, studies have examined performance of previous versions of Physilog® wearable inertial sensors but predominant focus has been on older adults. Despite their different gait patterns and behavioural/cognitive profiles, there are limited studies in children. RESEARCH QUESTION: To determine whether key spatiotemporal gait parameters (stride length, time and velocity) collected by shoe-worn Physilog®5 sensors in a hallway assessment protocol are a valid method of gait assessment in typically developing adolescents aged 12-15 years. METHODS: A total 30 typically developing participants (50 % female) median age 13.7 (interquartile range 2.34) were assessed in an exploratory study whilst walking at self-selected speed over the GAITRite® electronic walkway, concurrently wearing Physilog®5 sensors. Concurrent validity was analysed by Lin's concordance correlation coefficient (CCC), Bland-Altman plots and 95 % limit of agreement. Systematic bias was assessed using 95 % confidence interval of the mean difference. RESULTS: Mean stride data demonstrated substantial agreement for stride length (CCC = 0.975) and stride velocity (CCC = 0.979) to almost perfect agreement for stride time (CCC > 0.996). Agreement between the technologies for individual stride-to-stride data remained high for stride time (CCC = 0.952); yet reduced for stride length (CCC = 0.868) and stride velocity (CCC = 0.877). Male/female differences in performance of the technology were observed for stride velocity, favouring females. SIGNIFICANCE: Physilog®5 inertial sensors accurately measure walking in adolescents, with stride time the most accurately detected parameter. This demonstrates that wearables can be used by researchers and clinicians working with adolescent groups as an alternative to fixed systems. These findings will ultimately pave the way to using wearables for assessments with children outside of the laboratory environment.


Asunto(s)
Zapatos , Dispositivos Electrónicos Vestibles , Adolescente , Anciano , Niño , Femenino , Marcha , Humanos , Masculino , Caminata
20.
Disabil Rehabil ; 44(10): 1889-1897, 2022 05.
Artículo en Inglés | MEDLINE | ID: mdl-32878485

RESUMEN

PURPOSE: To develop a consensus statement for the prescription of a Powered Wheelchair Standing Device (PWSD) in young people with Duchenne muscular dystrophy (DMD). MATERIALS AND METHODS: An international multidisciplinary panel comprising clinicians and users (young people with DMD) along with their parents was consulted. A literature review was undertaken and a Delphi method was utilised to generate consensus statements. To supplement limited literature, round one of the Delphi process comprised questions consistent with the International Classification of Functioning, Disability and Health model of disability to generate items based on expert opinion and was completed by 38 clinicians and nine users. Thirty-seven participants completed two further rounds rating the importance of each item with a five-point scale. Agreement of 70% or more participants for items indicated consensus. RESULTS: Consensus was reached for 47 of 80 items. Tolerance and comfort in supported standing for at least 10 min, ankle contracture less than 10 degrees and user goals reflecting motivation to use the standing function were agreed as necessary in guiding the decision to trial a PWSD. Evidence of family, therapist and servicing support were also considered critical in enabling continuity of PWSD use. CONCLUSIONS: PWSD is a mobility option that offers choice, control and opportunity for independence. This consensus statement can assist clinicians with decision-making around factors influencing successful implementation and optimisation of PWSD for young people with DMD.Implications for RehabilitationTolerance and comfort in supported standing for at least 10 minutes, ankle contracture limited to less than 10 degrees and the child's goals reflecting motivation to use the standing position were agreed to be necessary considerations in guiding the decision to trial a PWSD.Trialling a PWSD when the child is predicted to lose the ability to walk within a one to two year period was recommended although a PWSD could be suitable for a child who was unable to walk.Evidence of family, therapist and servicing support was considered critical in enabling continuity of PWSD use.


Asunto(s)
Contractura , Distrofia Muscular de Duchenne , Silla de Ruedas , Adolescente , Niño , Técnica Delphi , Humanos , Prescripciones , Posición de Pie
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