10,299 research outputs found
Self-report prevalence and associated factors to drug hypersensitivity in Mexican young adults
Background: Drug hypersensitivity is defined as any unfavorable reaction that occurs after the administration of any drug. It may
or may not be mediated by the involvement of the immune system. Epidemiological data related to drug hypersensitivity reactions
in our country are scarce.
Objective: To determine the prevalence of drug hypersensitivity in a group of young adults, as well as to identify associated
factors.
Methods: A structured questionnaire was applied to young people aged 18 to 25 years. The instrument was oriented to identify
reactions of drug hypersensitivity, as well as the most prevalent drugs involved. In addition, a personal and family history of atopic
diseases was included. Analysis for associations between variables was been done through logistic regression.
Results: The prevalence of drug hypersensitivity reactions was 12% (144 of 1,200). The antibiotics were the agents most related
to hypersensitivity reactions (9.8%) followed by nonsteroidal anti-inflammatory drugs (1.6%). Factors associated with drug
hypersensitivity were a personal history of asthma, odds ratio (OR) 3.15 (95% confidence interval [CI], 1.44–6.91), maternal and
paternal history of drug hypersensitivity, OR 2.33 (95% CI, 1.21–4.48) and OR 3.11 (95% CI, 1.22–7.92), respectively.
Conclusion: The results of this research show that drug hypersensitivity in young adults is a highly prevalent event and it is
associated with personal history of asthma and history of drug hypersensitivity in parents
Intrinsic Deviation from the Tri-bimaximal Neutrino Mixing in a Class of A_4 Flavor Models
It is well known that the tri-bimaximal neutrino mixing pattern V_0 can be
derived from a class of flavor models with the non-Abelian A_4 symmetry. We
point out that small corrections to V_0, which are inherent in the A_4 models
and arise from both the charged-lepton and neutrino sectors, have been omitted
in the previous works. We show that such corrections may lead the 3 \times 3
neutrino mixing matrix V to a non-unitary deviation from V_0, but they cannot
result in a nonzero value of \theta_13 or any new CP-violating phases. Current
experimental constraints on the unitarity of V allow us to constrain the model
parameters to some extent.Comment: 11 pages, no figures; a reference added, accepted for publication in
Phys. Lett.
The Spanish HIV BioBank: a model of cooperative HIV research
<p>Abstract</p> <p>Background</p> <p>The collection of samples from HIV-infected patients is the beginning of the chain of translational research. To carry out quality research that could eventually end in a personalized treatment for HIV, it is essential to guarantee the availability, quality and traceability of samples, under a strict system of quality management.</p> <p>Methods</p> <p>The Spanish HIV BioBank was created with the objectives of processing, storing and providing distinct samples from HIV/AIDS patients, categorized according to strictly defined characteristics, free of charge to research projects. Strict compliance to ethical norms is always guaranteed.</p> <p>Results</p> <p>At the moment, the HIV BioBank possesses nearly 50,000 vials containing different prospective longitudinal study sample types. More than 1,700 of these samples are now used in 19 national and international research projects.</p> <p>Conclusion</p> <p>The HIV BioBank represents a novel approach to HIV research that might be of general interest not only for basic and clinical research teams working on HIV, but also for those groups trying to establish large networks focused on research on specific clinical problems. It also represents a model to stimulate cooperative research among large numbers of research groups working as a network on specific clinical problems. The main objective of this article is to show the structure and function of the HIV BioBank that allow it to very efficiently release samples to different research project not only in Spain but also in other countries.</p
LiNi0.5Mn1.5O4 Thin Films Grown by Magnetron Sputtering under Inert Gas Flow Mixtures as High-Voltage Cathode Materials for Lithium-Ion Batteries
Delivering a commercial high-voltage spinel LiNi0.5Mn1.5O4 (LNMO) cathode electrode for Li-ion batteries would result in a significant step forward in terms of energy density. However, the structural ordering of the spinel and particle size have considerable effects on the cathode material's cyclability and rate capability, which are crucial challenges to address. Here, a novel mid-frequency alternating current dual magnetron sputtering method was presented, using different Ar-N-2 gas mixtures ratios for the process gas to prepare various LNMO thin films with highly controlled morphology and particle size; as determined from X-ray diffraction, Raman spectroscopy and electron microscopy. It resulted in enhanced cycling and rate performance. This processing method delivered N-containing LNMO thin film electrodes with up to 15 % increased discharge capacity at 1 C (120 mAh g(-1)) with respect to standard LNMO (grown under only Ar gas flow) thin film electrodes, along with outstanding rate performance up to 10 C (99 mAh g(-1)) in the operating voltage window 3.5-4.85 V vs. Li+/Li. Besides, electrochemical impedance spectroscopy results showed that the intricate phase transitions present in standard LNMO electrodes were almost suppressed in N-containing LNMO thin films grown under different Ar-N-2 gas flow mixtures
Ignition sensitivity of solid fuel mixtures
Due to both environmental concerns and the depletion of the reserves of fossil fuels, alternative and more environmentally friendly fuels, such as biomass and waste products, are being considered for partial or full fossil fuel replacement. The main disadvantage of these products is their lower energy density compared to fossil fuels. To deal with this several heat and power generation facilities are co-firing fuel mixtures. These processes involve mixtures of flammable dusts whose ignitability and explosibility characteristics are not known and therefore present un-quantified safety risk to the new technologies.
This study reports on these risks and on the reactivity characteristics of two and three components dust mixtures of coal/sewage-sludge/torrefied-wood-pellet. In particular chemical composition, ignition sensitivity parameters (including minimum ignition energy, minimum ignition temperature on a layer, minimum explosive concentration) and flame speed have been determined. In all cases the measured parameters for the mixtures were within the range defined by the lower and upper value of the constituent. However, the expected values do not agree with the experimentally obtained ones, providing more relaxed values than the ones needed on this facilities
Calcium Homeostasis in Myogenic Differentiation Factor 1 (MyoD)-Transformed, Virally-Transduced, Skin-Derived Equine Myotubes
Dysfunctional skeletal muscle calcium homeostasis plays a central role in the pathophysiology of several human and animal skeletal muscle disorders, in particular, genetic disorders associated with ryanodine receptor 1 (RYR1) mutations, such as malignant hyperthermia, central core disease, multiminicore disease and certain centronuclear myopathies. In addition, aberrant skeletal muscle calcium handling is believed to play a pivotal role in the highly prevalent disorder of Thoroughbred racehorses, known as Recurrent Exertional Rhabdomyolysis. Traditionally, such defects were studied in human and equine subjects by examining the contractile responses of biopsied muscle strips exposed to caffeine, a potent RYR1 agonist. However, this test is not widely available and, due to its invasive nature, is potentially less suitable for valuable animals in training or in the human paediatric setting. Furthermore, increasingly, RYR1 gene polymorphisms (of unknown pathogenicity and significance) are being identified through next generation sequencing projects. Consequently, we have investigated a less invasive test that can be used to study calcium homeostasis in cultured, skin-derived fibroblasts that are converted to the muscle lineage by viral transduction with a MyoD (myogenic differentiation 1) transgene. Similar models have been utilised to examine calcium homeostasis in human patient cells, however, to date, there has been no detailed assessment of the cells’ calcium homeostasis, and in particular, the responses to agonists and antagonists of RYR1. Here we describe experiments conducted to assess calcium handling of the cells and examine responses to treatment with dantrolene, a drug commonly used for prophylaxis of recurrent exertional rhabdomyolysis in horses and malignant hyperthermia in humans
Association of VAV2 and VAV3 polymorphisms with cardiovascular risk factors
Hypertension, diabetes and obesity are cardiovascular risk factors closely associated to the development of renal and cardiovascular target organ damage. VAV2 and VAV3, members of the VAV family proto-oncogenes, are guanosine nucleotide exchange factors for the Rho and Rac GTPase family, which is related with cardiovascular homeostasis. We have analyzed the relationship between the presence of VAV2 rs602990 and VAV3 rs7528153 polymorphisms with cardiovascular risk factors and target organ damage (heart, vessels and kidney) in 411 subjects. Our results show that being carrier of the T allele in VAV2 rs602990 polymorphism is associated with an increased risk of obesity, reduced levels of ankle-brachial index and diastolic blood pressure and reduced retinal artery caliber. In addition, being carrier of T allele is associated with increased risk of target organ damage in males. On the other hand, being carrier of the T allele in VAV3 rs7528153 polymorphism is associated with a decreased susceptibility of developing a pathologic state composed by the presence of hypertension, diabetes, obesity or cardiovascular damage, and with an increased risk of developing altered basal glycaemia. This is the first report showing an association between VAV2 and VAV3 polymorphisms with cardiovascular risk factors and target organ damage
Non-standard interactions versus non-unitary lepton flavor mixing at a neutrino factory
The impact of heavy mediators on neutrino oscillations is typically described
by non-standard four-fermion interactions (NSIs) or non-unitarity (NU). We
focus on leptonic dimension-six effective operators which do not produce
charged lepton flavor violation. These operators lead to particular
correlations among neutrino production, propagation, and detection non-standard
effects. We point out that these NSIs and NU phenomenologically lead, in fact,
to very similar effects for a neutrino factory, for completely different
fundamental reasons. We discuss how the parameters and probabilities are
related in this case, and compare the sensitivities. We demonstrate that the
NSIs and NU can, in principle, be distinguished for large enough effects at the
example of non-standard effects in the --sector, which basically
corresponds to differentiating between scalars and fermions as heavy mediators
as leading order effect. However, we find that a near detector at superbeams
could provide very synergistic information, since the correlation between
source and matter NSIs is broken for hadronic neutrino production, while NU is
a fundamental effect present at any experiment.Comment: 32 pages, 5 figures. Final version published in JHEP. v3: Typo in Eq.
(27) correcte
MiniBooNE and LSND data: non-standard neutrino interactions in a (3+1) scheme versus (3+2) oscillations
The recently observed event excess in MiniBooNE anti-neutrino data is in
agreement with the LSND evidence for electron anti-neutrino appearance. We
propose an explanation of these data in terms of a (3+1) scheme with a sterile
neutrino including non-standard neutrino interactions (NSI) at neutrino
production and detection. The interference between oscillations and NSI
provides a source for CP violation which we use to reconcile different results
from neutrino and anti-neutrino data. Our best fit results imply NSI at the
level of a few percent relative to the standard weak interaction, in agreement
with current bounds. We compare the quality of the NSI fit to the one obtained
within the (3+1) and (3+2) pure oscillation frameworks. We also briefly comment
on using NSI (in an effective two-flavour framework) to address a possible
difference in neutrino and anti-neutrino results from the MINOS experiment.Comment: 28 pages, 9 figures, discussion improved, new appendix added,
conclusions unchange
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