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1.
Animal ; 17(10): 100967, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37742499

RESUMEN

Nitrogen (N) loss from livestock agriculture via ammonia and nitrous oxide can reduce feed efficiency, production and negatively affect the environment. One option to reduce N loss is to add dietary supplements such as Yucca schidigera extract which has ammonia-binding properties and contains antimicrobial steroidal saponins, or Saccharomyces cerevisiae yeast, which can stabilise rumen pH and promote fibre degradation, increasing microbial growth and demand for degradable N. To determine the effect of Yucca schidigera extract when fed alone or in combination with a live yeast on the performance, rumen metabolism, microbiome and N balance, six rumen cannulated dairy cows were fed a mixed ration (C), mixed ration with Y. schidigera extract (De-Odorase®, Alltech®; 5 g/cow/day; D), or mixed ration with Y. schidigera extract (5 g/day) and Saccharomyces cerevisiae (Yea-Sacc®, Alltech®, 1 g/cow per day; DY), in a 3 × 3 Latin rectangle design study with three periods of 49-day duration. Digesta samples were collected via the ruminal cannula during the final week of each period and separated into liquid (LPD) and solid (SPD) phases for microbiome analysis using 16S rRNA amplicon sequencing. DM intake was 0.8 kg/d lower (P < 0.05) in cows fed DY than C or D, with milk protein concentration 1.7 g/kg higher in C than D or DY. There was a beta diversity (Bray Curtis) clustering of the LPD in cows fed D or DY compared to C (P < 0.05), driven by an increase in Prevotella ruminicola-related operational taxonomic units (OTUs), and a decrease in P. brevis and P. bryantii OTUs. A methanogen OTU, Methanobrevibacter olleyae, was decreased in cows fed D or DY and an unclassified species of Gammaproteobacteria was increased in DY (LDA > 2.0, P < 0.05) compared to C. Rumen pH, ammonia and total VFA concentration were not affected by treatment (P > 0.05) but the concentration of propionate and iso-butyrate were lower at 1700 and 2000 h in cows fed DY compared to C (P < 0.05). Measurements of N balance were unaffected by supplementation with D or DY, and there was no effect of treatment on slurry pH. In conclusion, supplementing with an extract of Yucca schidigera either alone or in combination with a live yeast had only a small effect on performance, with Yucca schidigera altering species associated with carbohydrate and protein metabolism, and reduced Methanobrevibacter olleyae which is involved in methanogenesis.

3.
Rev Sci Instrum ; 92(4): 043520, 2021 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-34243436

RESUMEN

A machine learning approach has been implemented to measure the electron temperature directly from the emission spectra of a tokamak plasma. This approach utilized a neural network (NN) trained on a dataset of 1865 time slices from operation of the DIII-D tokamak using extreme ultraviolet/vacuum ultraviolet emission spectroscopy matched with high-accuracy divertor Thomson scattering measurements of the electron temperature, Te. This NN is shown to be particularly good at predicting Te at low temperatures (Te < 10 eV) where the NN demonstrated a mean average error of less than 1 eV. Trained to detect plasma detachment in the tokamak divertor, a NN classifier was able to correctly identify detached states (Te < 5 eV) with a 99% accuracy (an F1 score of 0.96) at an acquisition rate 10× faster than the Thomson scattering measurement. The performance of the model is understood by examining a set of 4800 theoretical spectra generated using collisional radiative modeling that was also used to predict the performance of a low-cost spectrometer viewing nitrogen emission in the visible wavelengths. These results provide a proof-of-principle that low-cost spectrometers leveraged with machine learning can be used to boost the performance of more expensive diagnostics on fusion devices and be used independently as a fast and accurate Te measurement and detachment classifier.

4.
Sci Rep ; 8(1): 6356, 2018 Apr 17.
Artículo en Inglés | MEDLINE | ID: mdl-29662149

RESUMEN

A correction to this article has been published and is linked from the HTML and PDF versions of this paper. The error has not been fixed in the paper.

5.
Sci Rep ; 7(1): 14254, 2017 10 27.
Artículo en Inglés | MEDLINE | ID: mdl-29079746

RESUMEN

The Wnt pathway is a new target in bone therapeutic space. WNT proteins are potent stem cell activators and pro-osteogenic agents. Here, we gained insights into the molecular and cellular mechanisms responsible for liposome-reconstituted recombinant human WNT3A protein (L-WNT3A) efficacy to treat osteonecrotic defects. Skeletal injuries were coupled with cryoablation to create non-healing osteonecrotic defects in the diaphysis of the murine long bones. To replicate clinical therapy, osteonecrotic defects were treated with autologous bone graft, which were simulated by using bone graft material from syngeneic ACTB-eGFP-expressing mice. Control osteonecrotic defects received autografts alone; test sites received autografts treated ex vivo with L-WNT3A. In vivo µCT monitored healing over time and immunohistochemistry were used to track the fate of donor cells and assess their capacity to repair osteonecrotic defects according to age and WNT activation status. Collectively, analyses demonstrated that cells from the autograft directly contributed to repair of an osteonecrotic lesion, but this contribution diminished as the age of the donor increased. Pre-treating autografts from aged animals with L-WNT3A restored osteogenic capacity to autografts back to levels observed in autografts from young animals. A WNT therapeutic approach may therefore have utility in the treatment of osteonecrosis, especially in aged patients.


Asunto(s)
Envejecimiento/metabolismo , Regeneración Ósea , Trasplante Óseo , Osteonecrosis/metabolismo , Vía de Señalización Wnt , Proteína Wnt3A/metabolismo , Anciano , Envejecimiento/patología , Animales , Autoinjertos , Humanos , Ratones , Ratones Transgénicos , Persona de Mediana Edad , Osteonecrosis/patología
6.
Int J Obes (Lond) ; 41(5): 820-823, 2017 05.
Artículo en Inglés | MEDLINE | ID: mdl-28133361

RESUMEN

Limited research has explored longitudinal impact of stress on negative health outcomes, including overweight and obesity in Asian societies. Using data from a longitudinal school-based health promotion study conducted in Wuhan, China from 1999 to 2004, this study investigated the longitudinal effects of childhood stress exposure, including stressors related to school, family, peers, violence and health on overweight, and obesity risk during the transition to adolescence among 2179 Chinese adolescents. Results showed that health stressors were consistently related to higher BMI Z score for both boys and girls baseline, it also predicted higher likelihood of overweight status over time for girls. This finding highlights a particularly challenging time period for girls, suggesting a particular challenging time they face at the intersection of puberty and demanding school environment.


Asunto(s)
Conducta del Adolescente/psicología , Imagen Corporal/psicología , Conducta Infantil/psicología , Promoción de la Salud , Obesidad Infantil/psicología , Estrés Psicológico/psicología , Adolescente , Niño , China/epidemiología , Femenino , Humanos , Estudios Longitudinales , Masculino , Obesidad Infantil/epidemiología , Maduración Sexual , Estrés Psicológico/epidemiología , Urbanización
7.
IDCases ; 6: 85-89, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27818944

RESUMEN

Salmonella species are facultative intracellular pathogens that most frequently cause self-limiting gastrointestinal disease, often acquired through the ingestion of contaminated food. We report the case of a 33-year-old otherwise healthy, not overtly immunosuppressed, man who was transferred to our facility with the chief complaint of respiratory failure and septic shock. Computed tomography of the chest revealed multifocal pneumonia in both lungs. A bronchial alveolar lavage was performed in the right middle lobe and cultures predominantly grew Salmonella enterica serovar Enteritidis. The patient received a prolonged course of antimicrobials, ultimately changing to oral levofloxacin. The etiology of the salmonella infection likely occurred through an aspiration event. Salmonella species are not a typical respiratory pathogen in immunocompetent hosts; however, clinicians should be aware of the possibility that salmonella species may be a pathogenic source of infection in the lungs; a prolonged course of antimicrobials may be warranted.

8.
Lab Chip ; 16(12): 2236-44, 2016 06 21.
Artículo en Inglés | MEDLINE | ID: mdl-27199277

RESUMEN

Solution pH is a powerful tool for regulating many kinds of chemical activity, but is generally treated as a static property defined by a pre-selected buffer. Introducing dynamic control of pH in space, time, and magnitude can enable richer and more efficient chemistries, but is not feasible with traditional methods of titration or buffer exchange. Recent reports have featured electrochemical strategies for modifying bulk pH in constrained volumes, but only demonstrate switching between two preset values and omit spatial control entirely. Here, we use a combination of solution-borne quinones and galvanostatic excitation to enable quantitative control of pH environments that are highly localized to an electrode surface. We demonstrate highly reproducible acidification and alkalinization with up to 0.1 pH s(-1) (±0.002 pH s(-1)) rate of change across the dynamic range of our pH sensor (pH 4.5 to 7.5) in buffered solutions. Using dynamic current control, we generate and sustain 3 distinct pH microenvironments simultaneously to within ±0.04 pH for 13 minutes in a single solution, and we leverage these microenvironments to demonstrate spatially-resolved, pH-driven control of enzymatic activity. In addition to straightforward applications of spatio-temporal pH control (e.g. efficiently studying pH-dependencies of chemical interactions), the technique opens completely new avenues for implementing complex systems through dynamic control of enzyme activation, protein binding affinity, chemical reactivity, chemical release, molecular self-assembly, and many more pH-controlled processes.

9.
J Appl Microbiol ; 120(4): 1074-84, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-26786717

RESUMEN

AIM: To develop test methods and evaluate survival of Bacillus thuringiensis kurstaki cry(-) HD-1 and B. thuringiensis Al Hakam spores after exposure to hot, humid air inside of a C-130 aircraft. METHODS AND RESULTS: Bacillus thuringiensis spores were either pre-inoculated on 1 × 2 or 2 × 2 cm substrates or aerosolized inside the cargo hold of a C-130 and allowed to dry. Dirty, complex surfaces (10 × 10 cm) swabbed after spore dispersal showed a deposition of 8-10 log10 m(-2) through the entire cargo hold. After hot, humid air decontamination at 75-80°C, 70-90% relative humidity for 7 days, 87 of 98 test swabs covering 0·98 m(2) , showed complete spore inactivation. There was a total of 1·67 log10 live CFU detected in 11 of the test swabs. Spore inactivation in the 98 test swabs was measured at 7·06 log10 m(-2) . CONCLUSIONS: Laboratory test methods for hot, humid air decontamination were scaled for a large-scale aircraft field test. The C-130 field test demonstrated that hot, humid air can be successfully used to decontaminate an aircraft. SIGNIFICANCE AND IMPACT OF THE STUDY: Transition of a new technology from research and development to acquisition at a Technology Readiness Level 7 is unprecedented.


Asunto(s)
Aeronaves , Bacillus anthracis/aislamiento & purificación , Bacillus thuringiensis/aislamiento & purificación , Descontaminación/métodos , Calor , Humedad , Bacillus anthracis/fisiología , Bacillus thuringiensis/fisiología , Epidemias/prevención & control , Esporas Bacterianas/crecimiento & desarrollo
10.
Geobiology ; 14(1): 68-90, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26407813

RESUMEN

Heavy metal-contaminated, pH 6 mine water discharge created new streams and iron-rich terraces at a creek bank in a former uranium-mining area near Ronneburg, Germany. The transition from microoxic groundwater with ~5 mm Fe(II) to oxic surface water may provide a suitable habitat for microaerobic iron-oxidizing bacteria (FeOB). In this study, we investigated the potential contribution of these FeOB to iron oxidation and metal retention in this high-metal environment. We (i) identified and quantified FeOB in water and sediment at the outflow, terraces, and creek, (ii) studied the composition of biogenic iron oxides (Gallionella-like twisted stalks) with scanning and transmission electron microscopy (SEM, TEM) as well as confocal laser scanning microscopy (CLSM), and (iii) examined the metal distribution in sediments. Using quantitative PCR, a very high abundance of FeOB was demonstrated at all sites over a 6-month study period. Gallionella spp. clearly dominated the communities, accounting for up to 88% of Bacteria, with a minor contribution of other FeOB such as Sideroxydans spp. and 'Ferrovum myxofaciens'. Classical 16S rRNA gene cloning showed that 96% of the Gallionella-related sequences had ≥ 97% identity to the putatively metal-tolerant 'Gallionella capsiferriformans ES-2', in addition to known stalk formers such as Gallionella ferruginea and Gallionellaceae strain R-1. Twisted stalks from glass slides incubated in water and sediment were composed of the Fe(III) oxyhydroxide ferrihydrite, as well as polysaccharides. SEM and scanning TEM-energy-dispersive X-ray spectroscopy revealed that stalk material contained Cu and Sn, demonstrating the association of heavy metals with biogenic iron oxides and the potential for metal retention by these stalks. Sequential extraction of sediments suggested that Cu (52-61% of total sediment Cu) and other heavy metals were primarily bound to the iron oxide fractions. These results show the importance of 'G. capsiferriformans' and biogenic iron oxides in slightly acidic but highly metal-contaminated freshwater environments.


Asunto(s)
Biota , Gallionellaceae/clasificación , Gallionellaceae/aislamiento & purificación , Metales Pesados/análisis , Microbiología del Agua , Aerobiosis , ADN Bacteriano/química , ADN Bacteriano/genética , ADN Ribosómico/química , ADN Ribosómico/genética , Compuestos Férricos/análisis , Gallionellaceae/química , Gallionellaceae/genética , Alemania , Concentración de Iones de Hidrógeno , Hierro/metabolismo , Microscopía Confocal , Microscopía Electroquímica de Rastreo , Microscopía Electrónica de Transmisión , Datos de Secuencia Molecular , Oxidación-Reducción , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN , Agua/química
11.
Mater Sci Eng C Mater Biol Appl ; 58: 1194-8, 2016 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-26478421

RESUMEN

III-nitride materials have recently received increasing levels of attention for their potential to successfully interface with, and sense biochemical interactions in biological systems. Expanding on available sensing schemes (including transistor-based devices,) a III-N lateral polarity structure capable of introducing quasi-phase matching through a periodic polarity grating presents a novel platform for second harmonic generation. This platform constitutes a non-linear optical phenomenon with exquisite sensitivity to the chemical state of a surface or interface. To characterize the response of a biological system to the nanostructured lateral polarity structures, we cultured neurotypic PC12 cells on AlGaN with varying ratios of Al:Ga - 0, 0.4, 0.6, and 1 - and on surfaces of varying pitch to the III-polar vs. N-polar grating - 5, 10, 20 and 50 µm. While some toxicity associated with increasing Al is observed, we documented and quantified trends in cell responses to the local material polarity and nanoscale roughness. The nitrogen-polar material has a significantly higher nanoscale roughness than III-polar regions, and a 80-200 nm step height difference between the III-polar and N-polar materials in the lateral polarity configuration generates adequate changes in topography to influence cell growth, improves cell adhesion and promotes cell migration along the direction of the features. As the designed material configuration is further explored for biochemical sensing, the lateral polarity scheme may provide a route in assessing the non-specific protein adsorption to this varying nano-topography that drives the subsequent cell response.


Asunto(s)
Compuestos de Aluminio/química , Adhesión Celular/efectos de los fármacos , Galio/química , Neuronas/citología , Neuronas/efectos de los fármacos , Compuestos de Aluminio/farmacología , Animales , Diferenciación Celular/efectos de los fármacos , Galio/farmacología , Células PC12 , Ratas , Semiconductores
12.
J Appl Microbiol ; 119(5): 1263-77, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26258399

RESUMEN

AIMS: To develop test methods and evaluate survival of Bacillus anthracis ∆Sterne or Bacillus thuringiensis Al Hakam on materials contaminated with dirty spore preparations after exposure to hot, humid air using response surface modelling. METHODS AND RESULTS: Spores (>7 log10 ) were mixed with humic acid + spent sporulation medium (organic debris) or kaolin (dirt debris). Spore samples were then dried on five different test materials (wiring insulation, aircraft performance coating, anti-skid, polypropylene, and nylon). Inoculated materials were tested with 19 test combinations of temperature (55, 65, 75°C), relative humidity (70, 80, 90%) and time (1, 2, 3 days). The slowest spore inactivation kinetics was on nylon webbing and/or after addition of organic debris. CONCLUSIONS: Hot, humid air effectively decontaminates materials contaminated with dirty Bacillus spore preparations; debris and material interactions create complex decontamination kinetic patterns; and B. thuringiensis Al Hakam is a realistic surrogate for B. anthracis. SIGNIFICANCE AND IMPACT OF THE STUDY: Response surface models of hot, humid air decontamination were developed which may be used to select decontamination parameters for contamination scenarios including aircraft.


Asunto(s)
Bacillus anthracis/crecimiento & desarrollo , Bacillus thuringiensis/crecimiento & desarrollo , Descontaminación/métodos , Esporas Bacterianas/crecimiento & desarrollo , Calor , Cinética
13.
Bull Environ Contam Toxicol ; 95(2): 164-70, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-25726008

RESUMEN

Changes in the blood parameters of fingerlings of Clarias gariepinus were investigated after 24 and 96-h of exposures to endosulfan. 180 fingerlings of C. gariepinus [mean weight (10.5±1.3 g); total length (11.2±1.2 cm)] were exposed to five different concentrations (1.00, 2.20, 4.80, 11.00, 23.00 µg/L) of endosulfan and a control for 96 h after being acclimatized for 21 days. After 24 h of exposure, microcytic hypochromic anemia was observed and all erythrocyte profiles tested showed significant variation (p<0.05) among the treatments except thrombocyte and mean corpuscular hemoglobin concentration. Macrocytic hyperchromic anemia was noticed after 96 h of exposure and all the hematological parameters varied significantly (p<0.05) except packed cell volume and red blood cell count. The study shows that endosulfan alters the hematology of C. gariepinus fingerlings. Therefore, awareness on the hazards associated with the use of endosulfan should be intensified and sound sustainable alternatives to endosulfan should be developed.


Asunto(s)
Anemia/inducido químicamente , Bagres/sangre , Endosulfano/toxicidad , Eritrocitos/efectos de los fármacos , Insecticidas/toxicidad , Animales , Recuento de Eritrocitos , Índices de Eritrocitos , Hematócrito , Hidrocarburos Clorados
14.
J Vet Intern Med ; 28(5): 1465-70, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25056694

RESUMEN

BACKGROUND: The duration of antacid-induced hypergastrinemia after cessation of administration of omeprazole and famotidine apparently has not been determined in dogs. HYPOTHESIS: That serum gastrin will return to basal concentrations by 7 days after cessation of famotidine or omeprazole administration. ANIMALS: Nine healthy, adult, male, research colony dogs. METHODS: Randomized, cross-over design. Serum gastrin was determined daily for 7 days to establish baseline concentrations. Famotidine (1.0 mg/kg q24h) or omeprazole (1.0 mg/kg q24h) was administered PO for 7 days followed by a 14-day washout. Serum concentrations of gastrin were determined daily during 7 days of administration and daily for 7 days after cessation of administration. Each drug was evaluated in 8 of the 9 dogs. RESULTS: Omeprazole caused a significant increase in serum gastrin concentration (37.2 ± 7.3 to 71.3 ± 19.0 ng/L; P = .006). Famotidine induced a transient increase in serum gastrin (37.2 ± 7.3 to 65.5 ± 38.5 ng/L; P = .02) that peaked at administration day 3 and declined thereafter. By day 7 after cessation of both drugs, there was no difference in serum gastrin concentrations compared to those before administration (famotidine P = .99; omeprazole P = .99). During or after administration, gastrin concentrations above 3 times the upper reference range were rare (12 of 224 samples). CONCLUSIONS AND CLINICAL IMPORTANCE: A 7-day withdrawal from short-term administration of famotidine or omeprazole is sufficient for serum gastrin to return to baseline concentrations. Withholding famotidine or omeprazole for longer before investigating pathologic causes of hypergastrinemia is unnecessary.


Asunto(s)
Antiulcerosos/farmacología , Famotidina/farmacología , Gastrinas/sangre , Omeprazol/farmacología , Animales , Perros/sangre , Perros/fisiología , Masculino
15.
J Appl Microbiol ; 117(2): 397-404, 2014 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-24807242

RESUMEN

AIM: The aim of the study was to develop test methods and evaluate survival of Francisella philomiragia cells and MS2 bacteriophage after exposure to PES-Solid (a solid source of peracetic acid) formulations with or without surfactants. METHODS AND RESULTS: Francisella philomiragia cells (≥7·6 log10 CFU) or MS2 bacteriophage (≥6·8 log10 PFU) were deposited on seven different test materials and treated with three different PES-Solid formulations, three different preneutralized samples and filter controls at room temperature for 15 min. There were 0-1·3 log10 CFU (<20 cells) of cell survival, or 0-1·7 log10 (<51 PFU) of bacteriophage survival in all 21 test combinations (organism, formulation and substrate) containing reactive PES-Solid. In addition, the microemulsion (Dahlgren Surfactant System) showed ≤2 log10 (100 cells) of viable F. philomiragia cells, indicating the microemulsion achieved <2 log10 CFU on its own. CONCLUSIONS: Three PES-Solid formulations and one microemulsion system (DSS) inactivated F. philomiragia cells and/or MS2 bacteriophage that were deposited on seven different materials. SIGNIFICANCE AND IMPACT OF THE STUDY: A test method was developed to show that reactive PES-Solid formulations and a microemulsion system (DSS) inactivated >6 log10 CFU/PFU F. philomiragia cells and/or MS2 bacteriophage on different materials.


Asunto(s)
Descontaminación/métodos , Desinfectantes/farmacología , Desinfección/métodos , Francisella/efectos de los fármacos , Levivirus/efectos de los fármacos , Ácido Peracético/farmacología , Viabilidad Microbiana/efectos de los fármacos , Tensoactivos
17.
J Anim Physiol Anim Nutr (Berl) ; 98(1): 56-64, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-23298172

RESUMEN

Previous studies from our laboratory have shown positive benefits of linoleic acid (LA) feeding for attenuation of rat heart failure (HF). However, another research group concluded LA feeding was detrimental to cardiac function, using the American Institute of Nutrition 76A (AIN) diet as a background diet for the experimental animals only. To reconcile these conflicting results and determine whether (i) AIN has effects on cardiovascular function, and (ii) AIN reverses the positive effects of LA feeding, studies were performed using spontaneously hypertensive heart failure (SHHF) rats in both a survival study with lifetime feeding of AIN (control: Purina 5001) and a 2 × 2 factorial design for 6 weeks in young male SHHF rats with background diet and LA as variables. During a lifetime of AIN feeding, mortality from heart failure is significantly accelerated, cardiolipin altered and triglycerides increased. In young rats, 6 weeks on the AIN diet promoted increased systolic and diastolic blood pressure, increased fed and fasting blood glucose, increased serum inflammatory eicosanoids, decreased docosahexanoic acid, increased posterior wall thickness in diastole and an altered cardiolipin subspecies profile. The addition of LA to the AIN diet was able to rescue blood pressure. However, the combination increased retroperitoneal fat mass, body weight and fed blood glucose beyond the levels with the AIN diet alone. Because the AIN diet has wide ranging effects on cardiovascular parameters, our results suggest that it should not be used in animal studies involving the cardiovascular system unless induction of cardiac dysfunction is the desired outcome.


Asunto(s)
Alimentación Animal/análisis , Dieta , Insuficiencia Cardíaca/inducido químicamente , Animales , Presión Sanguínea , Peso Corporal , Femenino , Masculino , Estado Nutricional , Ratas , Ratas Endogámicas SHR
18.
J Appl Microbiol ; 115(2): 398-408, 2013 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-23692445

RESUMEN

AIMS: To develop test methods and evaluate survival of Bacillus anthracis Ames, B. anthracis ∆Sterne and B. thuringiensis Al Hakam spores after exposure to PES-Solid (a solid source of peracetic acid), including PES-Solid formulations with bacteriostatic surfactants. METHODS AND RESULTS: Spores (≥ 7 logs) were dried on seven different test materials and treated with three different PES-Solid formulations (or preneutralized controls) at room temperature for 15 min. There was either no spore survival or less than 1 log (<10 spores) of spore survival in 56 of 63 test combinations (strain, formulation and substrate). Less than 2.7 logs (<180 spores) survived in the remaining seven test combinations. The highest spore survival rates were seen on water-dispersible chemical agent resistant coating (CARC-W) and Naval ship topcoat (NTC). Electron microscopy and Coulter analysis showed that all spore structures were intact after spore inactivation with PES-Solid. CONCLUSIONS: Three PES-Solid formulations inactivated Bacillus spores that were dried on seven different materials. SIGNIFICANCE AND IMPACT OF THE STUDY: A test method was developed to show that PES-Solid formulations effectively inactivate Bacillus spores on different materials.


Asunto(s)
Bacillus anthracis/efectos de los fármacos , Bacillus thuringiensis/efectos de los fármacos , Descontaminación/métodos , Desinfectantes/farmacología , Ácido Peracético/farmacología , Bacillus anthracis/ultraestructura , Bacillus thuringiensis/ultraestructura , Desinfectantes/química , Esporas Bacterianas/efectos de los fármacos , Esporas Bacterianas/ultraestructura
19.
J Appl Microbiol ; 113(5): 1037-51, 2012 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-22897143

RESUMEN

AIMS: To develop test methods and evaluate the survival of Bacillus anthracis ∆Sterne and Bacillus thuringiensis Al Hakam spores after exposure to hot, humid air. METHODS AND RESULTS: Spores (>7 logs) of both strains were dried on six different test materials. Response surface methodology was employed to identify the limits of spore survival at optimal test combinations of temperature (60, 68, 77°C), relative humidity (60, 75, 90%) and time (1, 4, 7 days). No spores survived the harshest test run (77°C, 90% r.h., 7 days), while > 6·5 logs of spores survived the mildest test run (60°C, 60% r.h., 1 day). Spores of both strains inoculated on nylon webbing and polypropylene had greater survival rates at 68°C, 75% r.h., 4 days than spores on other materials. Electron microscopy showed no obvious physical damage to spores using hot, humid air, which contrasted with pH-adjusted bleach decontamination. CONCLUSIONS: Test methods were developed to show that hot, humid air effectively inactivates B. anthracis ∆Sterne and B. thuringiensis Al Hakam spores with similar kinetics. SIGNIFICANCE AND IMPACT OF THE STUDY: Hot, humid air is a potential alternative to conventional chemical decontamination.


Asunto(s)
Bacillus anthracis/aislamiento & purificación , Bacillus thuringiensis/aislamiento & purificación , Descontaminación/métodos , Calor , Humedad , Aire , Microscopía Electrónica de Transmisión , Esporas Bacterianas/aislamiento & purificación , Esporas Bacterianas/ultraestructura , Estadística como Asunto
20.
Br J Radiol ; 85(1019): 1513-6, 2012 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-22763033

RESUMEN

The objective of this study was to describe the patterns of peer-reviewed general radiology publication rates with reference to deaneries in the UK. This was a retrospective bibliometric analysis of publications in the six highest cited general radiology journals. Publications were identified using a manual search in PubMed between 2005 and 2009. Publications originating from UK radiology departments were identified and subcategorised into primary institution of origin, deanery and publication type. The total number of radiology trainees in each deanery was obtained from the General Medical Council. 913 publications were included in the study. Original papers constituted 48.7% (n=445), review articles 30.3% (n=277) and case reports 17.4% (n=159). The median number of publications in each deanery was 27 [interquartile range (IQR) 11-60], and the median number of publications per trainee was 0.49 (IQR 0.31-0.88). The largest proportion of publications came from the London deanery (n=354, 38.8%), followed by Eastern 86 (9.4%), Oxford and Yorkshire 70 (7.7% each). Relative to the number of trainees within each deanery, Oxford had the highest number of publications per trainee (1.78), followed by East Midlands (1.5), London (1.25) and Eastern (0.99). There was a significantly higher publication rate for those deaneries with academic radiologists (p<0.0001). There is a marked difference in the volume of published work in the general radiology literature among UK deaneries, even accounting for differences in the number of trainees. This probably means that opportunities for training in research are similarly non-uniform.


Asunto(s)
Bibliometría , Investigación Biomédica/estadística & datos numéricos , Radiología/estadística & datos numéricos , Humanos , Facultades de Medicina/estadística & datos numéricos , Reino Unido
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