273 research outputs found
Enhanced direct oxidation of diclofenac (DCF) at a carbon paste electrode (CPE) modified with cellulose and its biodegradability by Scedosporium dehoogii
A novel carbon paste electrode modified with cellulose fibers and dedicated to diclofenac electroanalysis was prepared, optimized, and used for the determination of the kinetic parameters of DCF biodegradation by a filamentous fungus. The electrochemical response of the modified CPE was compared to that of the unmodified. This study conducted by cyclic voltammetry and linear sweep voltammetry allowed the optimization of the cellulose fibers modified CPE in terms of absence/presence of cellulose fibers, accumulation time (250 s), and initial potential (- 0.4 V/Ag/AgCl). Interestingly, in these conditions, the limit of detection observed through linear sweet voltammetry was found to be as low as 0.020 µmol L-1. This electrode was then used to follow the degradation of DCF. Our results demonstrated that among species belonging to the Scedosporium genus, S. dehoogii displayed the best assets in our process in terms of growth temperature and ability to metabolize DCF. More precisely, DCF biodegradation using S. dehoogii in the process revealed a kinetic of order of 1, a kinetic constant k of 0.012 day-1 and a half time of 57.8 days for an initial concentration of DCF of 1.65 ± 0.05 mg L-1 and at a temperature of 25°C. This study constitutes a solid proof of concept for future developments of fungal wastewater treatments for bioremediation of DCF which is refractory to standard bacterial-based bioprocesses
Physical mapping integrated with syntenic analysis to characterize the gene space of the long arm of wheat chromosome 1A
Background: Bread wheat (Triticum aestivum L.) is one of the most important crops worldwide and its production faces pressing challenges, the solution of which demands genome information. However, the large, highly repetitive hexaploid wheat genome has been considered intractable to standard sequencing approaches. Therefore the International Wheat Genome Sequencing Consortium (IWGSC) proposes to map and sequence the genome on a chromosome-by-chromosome basis.
Methodology/Principal Findings: We have constructed a physical map of the long arm of bread wheat chromosome 1A using chromosome-specific BAC libraries by High Information Content Fingerprinting (HICF). Two alternative methods (FPC and LTC) were used to assemble the fingerprints into a high-resolution physical map of the chromosome arm. A total of 365 molecular markers were added to the map, in addition to 1122 putative unique transcripts that were identified by microarray hybridization. The final map consists of 1180 FPC based or 583 LTC based contigs. Conclusions/Significance: The physical map presented here marks an important step forward in mapping of hexaploid bread wheat. The map is orders of magnitude more detailed than previously available maps of this chromosome, and the assignment of over a thousand putative expressed gene sequences to specific map locations will greatly assist future functional studies. This map will be an essential tool for future sequencing of and positional cloning within chromosome 1A
Serious Shortcomings in the Management of Children with Anaphylaxis in Scottish Schools
BACKGROUND: The United Kingdom incidence of anaphylaxis has increased very sharply over the last decade, with the highest rates of hospital admissions occurring in school-aged children. This raises concerns about the extent to which schools are aware of approaches to the prevention and treatment of anaphylaxis. METHODS AND FINDINGS: We undertook a national postal survey of 250 Scottish schools enquiring about approaches to managing children considered to be at risk of anaphylaxis. We obtained responses from 148 (60%) schools, 90 (61%) of which reported having at least one at risk child. Most (80%) schools with children considered to be at risk reported having personalised care plans and invariably reported having at least one member of staff trained in the emergency treatment of anaphylaxis. Access to adrenaline was available on-site in 97% of these schools. However, significantly fewer schools without children considered to be at risk reported having a trained member of staff (48%, p < 0.001), with access to adrenaline being very poor (12%, p < 0.001). Overall, 59% of respondents did not feel confident in their school's ability to respond in an emergency situation. CONCLUSIONS: Most schools with children considered to be at risk of anaphylaxis report using personal care plans and having a member of staff trained in the use of, and with access to, adrenaline. The picture is, however, less encouraging in schools without known at risk children, both in relation to staff training and access to adrenaline. The majority of schools with at risk children have poorly developed strategies for preventing food-triggered anaphylaxis reactions. There is a need for detailed national guidelines for all schools, which the Scottish Executive must now ensure are developed and implemented
Human iPSC-hepatocyte modeling of alpha-1 antitrypsin heterozygosity reveals metabolic dysregulation and cellular heterogeneity
Individuals homozygous for the “Z” mutation in alpha-1 antitrypsin deficiency are known to be at increased risk for liver disease. It has also become clear that some degree of risk is similarly conferred by the heterozygous state. A lack of model systems that recapitulate heterozygosity in human hepatocytes has limited the ability to study the impact of a single Z alpha-1 antitrypsin (ZAAT) allele on hepatocyte biology. Here, we describe the derivation of syngeneic induced pluripotent stem cells (iPSCs) engineered to determine the effects of ZAAT heterozygosity in iPSC-hepatocytes (iHeps). We find that heterozygous MZ iHeps exhibit an intermediate disease phenotype and share with ZZ iHeps alterations in AAT protein processing and downstream perturbations including altered endoplasmic reticulum (ER) and mitochondrial morphology, reduced mitochondrial respiration, and branch-specific activation of the unfolded protein response in cell subpopulations. Our model of MZ heterozygosity thus provides evidence that a single Z allele is sufficient to disrupt hepatocyte homeostatic function.This work was supported by an Alpha-1 Foundation John W. Walsh Translational Research Award (to J.E.K.); a CJ Martin Early Career Fellowship from the Australian National Health and Medical Research Council (to R.B.W.); NIH grant R01HL095993 (to D.N.K.); and NIH grants R01DK101501 (to A.A.W.) and R01DK117940 (to A.N.H. and A.A.W.). iPSC distribution and disease modeling is supported by NIH grants U01TR001810 (to D.N.K. and A.A.W.) and N0175N92020C00005 (to D.N.K.); and by The Alpha-1 Project (TAP), a wholly owned subsidiary of the Alpha-1 Foundation (to D.N.K. and A.A.W.)
Structured and unstructured continuous models for Wolbachia infections
We introduce and investigate a series of models for an infection of a diplodiploid host species by the bacterial endosymbiont Wolbachia. The continuous models are characterized by partial vertical transmission, cytoplasmic incompatibility and fitness costs associated with the infection. A particular aspect of interest is competitions between mutually incompatible strains. We further introduce an age-structured model that takes into account different fertility and mortality rates at different stages of the life cycle of the individuals. With only a few parameters, the ordinary differential equation models exhibit already interesting dynamics and can be used to predict criteria under which a strain of bacteria is able to invade a population. Interestingly, but not surprisingly, the age-structured model shows significant differences concerning the existence and stability of equilibrium solutions compared to the unstructured model
Referrals to a regional allergy clinic - an eleven year audit
<p>Abstract</p> <p>Background</p> <p>Allergy is a serious and apparently increasing public health problem yet relatively little is known about the types of allergy seen in routine tertiary practice, including their spatial distribution, co-occurrence or referral patterns. This study reviewed referrals over an eleven year period to a regional allergy clinic that had a well defined geographical boundary. For those patients confirmed as having an allergy we explored: (i) differences over time and by demographics, (ii) types of allergy, (iii) co-occurrence, and (iv) spatial distributions.</p> <p>Methods</p> <p>Data were extracted from consultant letters to GPs, from September 1998 to September 2009, for patients confirmed as having an allergy. Other data included referral statistics and population data by postcode. Simple descriptive analysis was used to describe types of allergy. We calculated 11 year standardised morbidity ratios for postcode districts and checked for spatial clustering. We present maps showing 11 year rates by postcode, and 'difference' maps which try to separate referral effect from possible environmental effect.</p> <p>Results</p> <p>Of 5778 referrals, 961 patients were diagnosed with an allergy. These were referred by a total of 672 different GPs. There were marked differences in referral patterns between GP practices and also individual GPs. The mean age of patients was 35 and there were considerably more females (65%) than males. Airborne allergies were the most frequent (623), and there were very high rates of co-occurrence of pollen, house dust mite, and animal hair allergies. Less than half (410) patients had a food allergy, with nuts, fruit, and seafood being the most common allergens. Fifteen percent (142) had both a food and a non-food allergy. Certain food allergies were more likely to co-occur, for example, patients allergic to dairy products were more likely to be allergic to egg.</p> <p>There were age differences by types of allergy; people referred with food allergies were on average 5 years younger than those with other allergies, and those allergic to nuts were much younger (26 Vs 38) than those with other food allergies.</p> <p>There was clear evidence for spatial clustering with marked clustering around the referral hospital. However, the geographical distribution varied between allergies; airborne (particularly pollen allergies) clustered in North Dartmoor and Exmoor, food allergies (particularly nut allergies) in the South Hams, and on small numbers, some indication of seafood allergy in the far south west of Cornwall and in the Padstow area.</p> <p>Conclusions</p> <p>This study shows marked geographical differences in allergy referrals which are likely to reflect a combination of environmental factors and GP referral patterns. The data suggest that GPs may benefit from education and ongoing decision support and be supported by public education on the nature of allergy. It suggests further research into what happens to patients with allergy where there has been low use of tertiary services and further research into cross-reactivity and co-occurrence, and spatial distribution of allergy.</p
Introduction of oral vitamin D supplementation and the rise of the allergy pandemic
The history of the allergy pandemic is well documented, enabling us to put the vitamin D hypothesis into its historical context. The purpose of this study is to compare the prevalence of rickets, vitamin D supply, and allergy prevalence at 50-year intervals by means of a retrospective analysis of the literature since 1880
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