185 research outputs found
Extended-spectrum beta-lactamases-producing <i>Escherichia coli</i> in common vampire bats <i>Desmodus rotundus</i> and livestock in Peru
Antibiotic resistance mediated by bacterial production of extendedâspectrum betaâlactamase (ESBL) is a global threat to public health. ESBL resistance is most commonly hospitalâacquired; however, infections acquired outside of hospital settings have raised concerns over the role of livestock and wildlife in the zoonotic spread of ESBLâproducing bacteria. Only limited data are available on the circulation of ESBLâproducing bacteria in animals. Here, we report ESBLâproducing Escherichia coli in wild common vampire bats Desmodus rotundus and livestock near Lima, Peru. Molecular analyses revealed that most of this resistance resulted from the expression of blaCTXâMâ15 genes carried by plasmids, which are disseminating worldwide in hospital settings and have also been observed in healthy children of Peru. Multilocus sequence typing showed a diverse pool of E. coli strains carrying this resistance that were not always host speciesâspecific, suggesting sharing of strains between species or infection from a common source. This study shows widespread ESBL resistance in wild and domestic animals, supporting animal communities as a potential source of resistance. Future work is needed to elucidate the role of bats in the dissemination of antibioticâresistant strains of public health importance and to understand the origin of the observed resistance
An approach towards rapid optical measurements of antioxidant activity in blueberry cultivars
Blueberries are well known for their high antioxidant levels. Compared to bilberries (V. myrtillus) with higher antioxidant activity and more intensive blue colour throughout the whole berry, highbush blueberries have the blue pigments concentrated in the skin. Highbush blueberry skin is found to contain a very high content of phenolic compounds. To measure the total antioxidant activity in blueberries, several methods, mostly destructive, including the FRAP assay, have been used. This work is an initial approach towards a simple and rapid method, combining optical and antioxidant activity measurements. Highbush blueberry (V. corymbosum) cultivars âBluecropâ, âHardyblueâ, âPatriotâ, and lowbush cultivars âPutteâ (a hybrid originated from V. angustifolium) and âAronâ (V. corymbosum x V. uliginosum) were grown at the Norwegian University of Life Sciences (59Âș 40âN). Berries were harvested at commercial blue-ripe stage of maturity. Fresh berries were cut horizontally and placed on a scanner in order to examine berry size and skin thickness. Berries were weighed, and analysed for antioxidant activity using the FRAP (Ferric Reducing Ability of Plasma) assay. The FRAP assay is a non-specific method based on absorption changes following a reduction of a ferric- to a ferrous-complex in the presence of antioxidants.Own previous results have shown that antioxidant activity and berry weight varied between cultivars (REMBERG et al., 2003). Small berries had higher antioxidant activity compared to larger berries. In this follow-up project, skin thickness and berry diameter were measured by using an image- processing program. Berry and skin cross-section areas were correlated with the antioxidant activity
Maximizing realized yield by breeding for disease tolerance: A case study for Septoria tritici blotch
Disease-tolerant cultivars maintain yield in the presence of disease. When disease intensity is high, they can improve a grower's net return compared to less tolerant cultivars. Many authors report a trade-off, whereby higher fully protected yields are correlated with a lower disease tolerance. We analyse the question for breeders: to what extent should they breed for tolerance when it compromises maximizing fully protected yield? Field trials with 147 progeny from five parental crosses of wheat were used to measure yield and tolerance under a range of disease intensities from Septoria tritici blotch (STB; causal organism Zymoseptoria tritici) at a range of sites and seasons. The data define the variation for these traits from which breeders can select. A simple data-driven descriptive model was used to calculate the combination of tolerance and fully protected yield that maximizes actual yield for any given level of diseaseâquantified by loss of healthy canopy area duration (HAD-loss). This model was combined with data on the year-to-year variability of HAD-loss in the UK to calculate the tolerance and fully protected yield that maximizes the mean actual yield. We found that even when an effective fungicide treatment programme is applied, breeding for tolerance increases the mean actual yield. Some commercially available cultivars were found to have a level of tolerance that leads to yields close to the maximum yield in the presence of disease, others had a lower tolerance leading to suboptimal yields
Calcitonin gene-related peptide promotes cellular changes in trigeminal neurons and glia implicated in peripheral and central sensitization
<p>Abstract</p> <p>Background</p> <p>Calcitonin gene-related peptide (CGRP), a neuropeptide released from trigeminal nerves, is implicated in the underlying pathology of temporomandibular joint disorder (TMD). Elevated levels of CGRP in the joint capsule correlate with inflammation and pain. CGRP mediates neurogenic inflammation in peripheral tissues by increasing blood flow, recruiting immune cells, and activating sensory neurons. The goal of this study was to investigate the capability of CGRP to promote peripheral and central sensitization in a model of TMD.</p> <p>Results</p> <p>Temporal changes in protein expression in trigeminal ganglia and spinal trigeminal nucleus were determined by immunohistochemistry following injection of CGRP in the temporomandibular joint (TMJ) capsule of male Sprague-Dawley rats. CGRP stimulated expression of the active forms of the MAP kinases p38 and ERK, and PKA in trigeminal ganglia at 2 and 24 hours. CGRP also caused a sustained increase in the expression of c-Fos neurons in the spinal trigeminal nucleus. In contrast, levels of P2X<sub>3 </sub>in spinal neurons were only significantly elevated at 2 hours in response to CGRP. In addition, CGRP stimulated expression of GFAP in astrocytes and OX-42 in microglia at 2 and 24 hours post injection.</p> <p>Conclusions</p> <p>Our results demonstrate that an elevated level of CGRP in the joint, which is associated with TMD, stimulate neuronal and glial expression of proteins implicated in the development of peripheral and central sensitization. Based on our findings, we propose that inhibition of CGRP-mediated activation of trigeminal neurons and glial cells with selective non-peptide CGRP receptor antagonists would be beneficial in the treatment of TMD.</p
Vaccino antinfluenzale stagionale in Italia: misurare l’efficacia sul campo e la sicurezza : Stagione 2015-2016
In Italia, nella stagione influenzale 2015-2016 sono stati condotti dall\u2019Istituto Superiore di Sanit\ue0 (ISS), con il supporto dell\u2019Agenzia Italiana del Farmaco (AIFA), due studi al fine di stimare l\u2019efficacia sul campo (I-MOVE, Influenza - Monitoring Vaccine Effectiveness) e valutare la sicurezza (SVEVA, Studio sulla Valutazione degli Eventi dopo Vaccinazione Antinfluenzale) del vaccino antinfluenzale. Nel complesso hanno aderito 8 Regioni che corrispondono a oltre met\ue0 della popolazione italiana nel 2015 (non tutte le Regioni hanno aderito a entrambi gli obiettivi di studio). Nello studio I-MOVE sono stati reclutati 1.094 casi di ILI (Influenza-Like Illness), dai 64 medici di medicina generale e pediatri di libera scelta partecipanti (506 casi e 498 controlli). I risultati suggeriscono che il vaccino ha conferito una protezione moderata nei confronti del tipo virale A(H1N1)pdm09 e molto bassa per A(H3N2) e B a causa del sostanziale grado di mismatch antigenico osservato, rispetto al ceppo vaccinale. Nello studio SVEVA sono stati monitorati 3.213 soggetti vaccinati e rilevati 854 (26%) eventi dopo 7 giorni dalla vaccinazione, la maggior parte dei quali di lieve entit\ue0. Al fine di ottenere stime di efficacia pi\uf9 solide e descrivere eventi avversi rari, \ue8 necessario tuttavia raggiungere una numerosit\ue0 campionaria maggiore.In Italy, during the 2015/2016 flu season, the National Institute of Health (ISS), with the support of the Italian Drug Agency (AIFA), conducted two studies to estimate vaccine effectiveness (I-MOVE) and evaluate safety (SVEVA) of the flu vaccine. A total of 8 regions, among 21, participated to the study which can correspond to more than 50% of the Italian population in 2015 (not all regions participated to both objectives of the study). For the I-MOVE study, 1094 cases of ILI (506 cases and 498 controls) were recruited by 64 general practitioners and pediatricians. The results indicate that the vaccine gave moderate protection against the virus type A (H1N1) pdm09 and very low protection for A (H3N2) and B due to the antigenic mismatch that was observed, compared to the vaccine strain. For SVEVA study, 3213 vaccinated cases were monitored and 854 (26%) side effects were notified after 7 days of vaccination, the major part were mild. In order to obtain more solid data regarding vaccine effectiveness, and to describe rare adverse events, it is necessary to increase the sample size of both studies
Megasatellites: a peculiar class of giant minisatellites in genes involved in cell adhesion and pathogenicity in Candida glabrata
Minisatellites are DNA tandem repeats that are found in all sequenced genomes. In the yeast Saccharomyces cerevisiae, they are frequently encountered in genes encoding cell wall proteins. Minisatellites present in the completely sequenced genome of the pathogenic yeast Candida glabrata were similarly analyzed, and two new types of minisatellites were discovered: minisatellites that are composed of two different intermingled repeats (called compound minisatellites), and minisatellites containing unusually long repeated motifs (126â429 bp). These long repeat minisatellites may reach unusual length for such elements (up to 10 kb). Due to these peculiar properties, they have been named âmegasatellitesâ. They are found essentially in genes involved in cellâcell adhesion, and could therefore be involved in the ability of this opportunistic pathogen to colonize the human host. In addition to megasatellites, found in large paralogous gene families, there are 93 minisatellites with simple shorter motifs, comparable to those found in S. cerevisiae. Most of the time, these minisatellites are not conserved between C. glabrata and S. cerevisiae, although their host genes are well conserved, raising the question of an active mechanism creating minisatellites de novo in hemiascomycetes
Gram Negative Wound Infection in Hospitalised Adult Burn Patients-Systematic Review and Metanalysis-
BACKGROUND:
Gram negative infection is a major determinant of morbidity and survival. Traditional teaching suggests that burn wound infections in different centres are caused by differing sets of causative organisms. This study established whether Gram-negative burn wound isolates associated to clinical wound infection differ between burn centres.
METHODS:
Studies investigating adult hospitalised patients (2000-2010) were critically appraised and qualified to a levels of evidence hierarchy. The contribution of bacterial pathogen type, and burn centre to the variance in standardised incidence of Gram-negative burn wound infection was analysed using two-way analysis of variance.
PRIMARY FINDINGS:
Pseudomonas aeruginosa, Klebsiella pneumoniae, Acinetobacter baumanni, Enterobacter spp., Proteus spp. and Escherichia coli emerged as the commonest Gram-negative burn wound pathogens. Individual pathogens' incidence did not differ significantly between burn centres (F (4, 20)â=â1.1, pâ=â0.3797; r2â=â9.84).
INTERPRETATION:
Gram-negative infections predominate in burn surgery. This study is the first to establish that burn wound infections do not differ significantly between burn centres. It is the first study to report the pathogens responsible for the majority of Gram-negative infections in these patients. Whilst burn wound infection is not exclusive to these bacteria, it is hoped that reporting the presence of this group of common Gram-negative "target organisms" facilitate clinical practice and target research towards a defined clinical demand.peer-reviewe
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