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1.
Sci Total Environ ; 715: 136955, 2020 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-32014777

RESUMO

The relationship between the concentrations of metals in moss tissues and atmospheric deposition is highly complex, resulting in a general lack of correlations between these two matrices. Here, we tried to improve the significance of the moss-bulk deposition (BD) relationship by eliminating the mismatch between the time that the moss tissue selected for analysis is exposed to atmospheric deposition, and the time during which BD is collected. For this, we analysed the concentrations of Cd, Hg and Pb in new grown tissue of Pseudoscleropodium purum and BD collected monthly, for one year, in 21 sampling sites (SS) under different degrees of pollution. Additionally, we assessed how different moss tissues, including native moss (green parts and new grown tissues of P. purum) and moss transplants of Sphagnum denticulatum, reflect BD to find out which moss tissues provide a better estimate of the atmospheric deposition of heavy metals. First of all, our results showed that eliminating the mismatch between native moss exposure time and BD collection period is not enough to improve their correlation. Environmental variation emerged as the main driver of tissue content variation altering the moss-BD relationship unpredictably. Secondly, native P. purum represents BD values better than devitalized transplants by displaying a greater number of significant correlations with BD. Specifically, green parts of P. purum generally represent better BD than new grown tissues. Overall, we conclude that neither native mosses nor transplants are good estimators of atmospheric heavy metal deposition rates. However, they are good qualitative indicators of the atmospheric deposition, by allowing us to differentiate SS subject to a wide range of pollution levels. Additionally, green parts of P. purum, and likely of other mosses with similar growth forms, should be used in passive biomonitoring studies to make results from different studies comparable.

2.
ISME J ; 2020 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-32034281

RESUMO

Marine picocyanobacteria of the Prochlorococcus and Synechococcus genera have been longtime considered as autotrophic organisms. However, compelling evidence published over the last 15 years shows that these organisms can use different organic compounds containing key elements to survive in oligotrophic oceans, such as N (amino acids, amino sugars), S (dimethylsulfoniopropionate, DMSP), or P (ATP). Furthermore, marine picocyanobacteria can also take up glucose and use it as a source of carbon and energy, despite the fact that this compound is devoid of limiting elements and can also be synthesized by using standard metabolic pathways. This review will outline the main findings suggesting mixotrophy in the marine picocyanobacteria Prochlorococcus and Synechococcus, and its ecological relevance for these important primary producers.

5.
Artigo em Inglês | MEDLINE | ID: mdl-31932268

RESUMO

BACKGROUND AND OBJECTIVE: The DRESS syndrome (Drug Reaction with Eosinophilia and Systemic Symptoms) is a complex multisystemic severe drug hypersensitivity reaction whose diagnosis and management are troublesome. It involves the management by different specialists. The correct identification of the culprit drug is essential for future safe therapeutical options for the patient. There are no previous Spanish guidelines or consensus statements on DRESS syndrome. Objective: To draft a review and guidelines on the clinical and allergy diagnosis, management treatment and prevention of DRESS syndrome in light of currently available scientific evidence and the experience of multidisciplinary experts. METHODS: These guidelines have been elaborated by a panel of allergy specialists from the Drug Allergy Committee of the Spanish Society of Allergy and Clinical Immunology (SEAIC), together with other medical specialists involved in the management of DRESS syndrome and researchers from PIELenRed consortium. A review was conducted of scientific papers on DRESS syndrome and the expert panel evaluated the quality of the evidence of the literature and provided grades of recommendation. Wherever evidence was lacking, a consensus was reached among the experts. RESULTS: The first Spanish guidelines on DRESS syndrome are now being published. Important aspects as practical recommendations about clinical diagnosis, identification of the culprit drug through the Spanish pharmacovigilance system algorithm and allergy study have been addressed. Management, treatment and prevention recommendations are provided. Algorithms about management of DRESS in acute and recovery phase have been elaborated. An expert consensus step-wise guidelines for management and treatment of DRESS syndrome are provided.

6.
Plant Dis ; : PDIS10192086RE, 2020 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-31958250

RESUMO

Silverleaf caused by the basidiomycete Chondrostereum purpureum affects numerous woody species, including fruit tree crops like apple, resulting in wood necrosis and foliar silvering. There are no curative alternatives for this disease, and its management is by prevention methods. Therefore, the aim of this study was to develop a rapid diagnostic tool for the detection and identification of C. purpureum directly from woody tissues to help distinguish the pathogen from other basidiomycetes that are commonly found on apple. The silverleaf pathogen was isolated from different hosts and locations, and Koch's postulates were performed by inoculating the isolates on apple cuttings and measuring internal necrosis. A previously described APN 1 pair of primers specificity was also tested against 25 C. purpureum isolates in this study, using other wood rotting species as negative controls. Seven virulent isolates were inoculated on apple cuttings, and DNA was extracted from the cuttings' sawdust and amplified using APN 1, after 22 days of incubation. To prove the efficiency of the method in the field, DNA from healthy nursery plants inoculated with two virulent isolates, and naturally infected plants showing different levels of foliar symptoms, were tested. Presence of the fungus was verified by reisolation on APDA in all assays. Koch's postulates indicated that all C. purpureum isolates were pathogenic, showing different virulence levels, and APN 1 primers were able to discriminate them from other basidiomycetes. The method was also able to detect C. purpureum from artificially inoculated plants as well as naturally infected ones, demonstrating that the protocol may become a rapid minimally destructive diagnostic tool to detect the pathogen without the need to isolate it from tissues, and thus taking measures to prevent its dissemination.

7.
Artigo em Inglês | MEDLINE | ID: mdl-31958016

RESUMO

In this paper, we characterized the hyperelastic and damage behavior of the Extensor Digitorum Longus (EDL) human tendon under loading conditions. The study was conducted in both categories of models, phenomenological and physically motivated, to allow the prediction and the macroscopic response of the tendon under specific loading conditions, assuming that its response follows a hyperelastic anisotropic model in conjunction with damage law. We benchmarked multiple hyperelastic and damage models to fit the response of the tendons in uniaxial tensile loading conditions, and by employing a genetic algorithm, we obtained the material parameters for both elastic and damage models. The objective of this study was to explore different mathematical models to determine which would be the best option to predict the behavior of tendons and ligaments in complex biological systems using Finite Elements (FE) models. Therefore, we took into account accuracy as well as computational features. We considered the model proposed by Shearer and coupled it with a sigmoid function, which governs the evolution of damage in tendons, as the most appropriate for the fitting of the experimental data. The achieved solution shows to be of high interest attributable to the simplicity of the damage law function and its low computational cost.

8.
Artigo em Inglês | MEDLINE | ID: mdl-31972320

RESUMO

OBJECTIVES: To investigate the rectal carriage of multidrug-resistant Enterobacteriaceae (colistin resistant, ESBL-producers and/or carbapenemase-producers) among health care workers (HCWs) from six Spanish hospitals. METHODS: Rectal swabs from 258 HCWs, employed in intensive care units, hematology wards and clinical microbiology laboratories from six hospitals in northern Spain were studied. They were cultured in selective media for Gram negative resistant bacteria. Detection of antimicrobial resistance genes and MLST were performed by PCR and further sequencing. A questionnaire including data related to risk factors of colonization/infection by resistant bacteria (age, gender, chronic diseases, immunosuppressive therapies, invasive procedures or antimicrobial treatments) was given to each participant. RESULTS: No carbapenemase-producing Enterobacteriaceae were recovered. However, 8/258 HCWs (3.1%) were positive for ESBL-producing isolates. This rate was not higher than the colonization rate previously reported in Spain for healthy people in the community. Five isolates showed high level resistance to colistin (MICs ranging from 8 mg/L to 128 mg/L) but all of them were negative for the mcr genes tested. No statistically-significant risk factors for gut colonization by ESBL-producing or colistin resistant Enterobacteriaceae were identified among the HCW participating in the study. CONCLUSIONS: Our data suggest that working in hospitals does not represent a risk for rectal carriage of multidrug resistant Enterobacteriaceae.

10.
J Exp Bot ; 2020 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-31985797

RESUMO

Mycorrhizal plants (AM) display enhanced resistance to several pathogens. However, the molecular mechanisms regulating Mycorrhiza-Induced Resistance (MIR) are still elusive. We aim to study the mechanisms underlying MIR against Botrytis cinerea and the role of callose accumulation during this process. Mycorrhizal tomato plants inoculated with Rhizoglomus irregularis displayed callose priming upon B. cinerea infection. The callose inhibitor 2-deoxy-D-glucose abolished MIR, confirming the relevance of callose in the bioprotection phenomena. While studying the mechanisms underlying mycorrhiza-induced callose priming, we found that AM plants display an enhanced starch degradation rate that is correlated with the increased levels of ß-amylase1 transcripts following pathogen infection. Starch mobilization in AM plants seems coordinated with the increased transcription of sugar transporter and invertase genes. Moreover, the expression levels of genes coding the vesicular trafficking proteins ATL31 and SYP121 and callose synthase PMR4 were higher in the AM plants and further boosted following pathogen infection. These proteins are all key elements in the priming of callose accumulation in Arabidopsis, suggesting that callose priming is an induced resistance mechanism conserved in different plant species. This evidence highlights the importance of sugar mobilization and vesicular trafficking in the priming of callose as a defence mechanism in MIR.

11.
Neurosci Lett ; 715: 134632, 2020 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-31790719

RESUMO

The selective breeding of laboratory rodents with different anxiety-related traits is the subject of growing interest. The present study compared the effects of the benzodiazepine midazolam in the elevated plus maze (EPM) test of anxiety in two lines of Wistar rats that were selectively bred in our laboratory for either high or low anxiety-like traits based on a contextual freezing conditioning paradigm. After phenotyping anxiety-like traits (i.e., conditioned freezing behavior), Carioca High-Freezing [CHF], Carioca Low-Freezing [CLF]) and control rats were intraperitoneally injected (1.0 ml/kg) with .9 % saline or midazolam (.25, .5, .75, and 1.0 mg/kg) and subjected to the EPM 30 min later. After the saline injection, the CHF and CLF groups exhibited lower and higher open-arm exploration in the EPM, respectively, compared with control rats. These results indicate that anxiety-related traits previously selected from an associative learning paradigm can also be phenotypically expressed in an ethologically based animal model of anxiety. All midazolam doses significantly increased open-arm exploration in both CHF and control animals, but this anxiolytic-like effect in CLF rats was only observed at the lowest dose tested (.25 mg/kg). The present findings indicate that these two breeding lines of rats are a useful model for studying anxiety, and the anxiolytic effect of midazolam depends on genetic variability that is associated with basal reactions to threatening situations.

12.
Br J Oral Maxillofac Surg ; 58(1): 69-74, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31708224

RESUMO

To evaluate and compare outcomes and complications associated with reconstruction of the temporomandibular joint (TMJ), we prospectively analysed the data of 70 patients who had their joints replaced with stock prostheses during the period 2004-14 and who had been followed up for five years. We used two types of stock prostheses: the metal-on-metal Christensen system (CS), and the ultra-high-molecular-weight-polyethylene-on-metal Biomet® system (BS). Data were collected at 3, 6, 12, 24, 36, 48, and 60 months postoperatively and compared with preoperative measurements. Five years after the replacement there was an increase in mean (SD) mouth opening from 2.0 (0.6) to 4.0 (0.5cm) (p=0.012) in the CS, and from 2.5 (1.0) cm to 4.1 (0.6) cm (p=0.018) in the BS. The mean (SD) reductions in visual analogue pain scores were from 6.9 (1.6) to 2.0 (1.4) (p=0.001) in the CS, and 6.5 (1.4) to 1.5 (1.1) (p=0.001) in the BS. There were no significant differences in improvements in mouth opening or reduction in pain between the two groups. However, there were differences in the number of implants that failed, which led to removal and replacement of 2/14 prostheses in the CS group and 3/77 in the BS group (p=0.06). The results supported the placement of stock prostheses, as evidenced by a low incidence of complications and adverse events, and a long-term improvement in function and reduction in pain in the TMJ. The BS group had significantly fewer prosthetic failures than the CS group.

13.
Dev Dyn ; 249(1): 141-153, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31736174

RESUMO

BACKGROUND: At the earliest stages of brain development, the neuroepithelium works as an interdependent functional entity together with cerebrospinal fluid, which plays a key regulatory role in neuroepithelial cell survival, replication and neurogenesis; however, the underlying mechanism remains unknown in mammals. RESULTS: We show the presence of fibroblast growth factor 2 (FGF2) and epidermal growth factor (EGF), in 13.5-day rat embryo cerebrospinal fluid (eCSF). Immunohistochemical detection of FGF2 expression localized this factor inside neuroepithelial precursors close to the neuroepithelial-CSF interface, suggesting that FGF2 from eCSF could originate in the neuroepithelium by apical secretion. The colocalization of FGFR1 and FGF2 in some neuroepithelial cells close to the ventricular surface suggests they are target cells for eCSF FGF2. Brain neuroepithelium EGF expression was negative. By using a neuroepithelial organotypic culture, we demonstrate that FGF2 and EGF from eCSF plays a specific role in triggering the self-renewal and are involved in neurogenetic induction of mesencephalic neuroepithelial precursor cells during rat development. CONCLUSIONS: We propose eCSF as an intercommunication medium for neuroepithelial precursor behavior control during early rat brain development, and the neuroepithelial regulation of FGF2 and EGF presence in eCSF, as a regulative mechanism controlling precursor proliferation and neurogenesis.

14.
Comput Biol Med ; 116: 103529, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31715382

RESUMO

Chronic lower lumbar pain has been associated with elevated bone metabolic activity in the spine. Diagnosis of bone metabolic activity is currently through integrating Positron Emission Tomography (PET) with Sodium Fluoride (18F-NaF) biomarkers. It has been reported that numerous observable pathologies including lumbar fusion, disc abnormalities and scoliosis have often been associated with increased 18F-NaF uptake. The aim of this study was to identify what features of lower lumbar shape most strongly correlate with 18F-NaF uptake. Following a principal component analysis of 23 patients who presented with lumbar pain and underwent 18F-NaF PET-CT, it was revealed that three modes interpreted as (i) sacral tilt, (ii) vertebral disc spacing and (iii) spine size were the three characteristics that described 88.7% of spine shape in our study population. 18F-NaF was described by two modes including 18F-NaF intensity and spatial variation (anterior-inferior to posterior-superior). 18F-NaF was most sensitive to sacral tilt followed by vertebral disc spacing. A predictive model derived from that spine population was able to predict 18F-NaF 'hot-spot' locations with 85 ±â€¯5% accuracy and with 71 ±â€¯3% accuracy for the 18F-NaF magnitude. These results suggest that patients reporting with lower lumbar pain and who present with increased sacral tilt profiles and/or reduced disc spacing are good candidates for further 18F-NaF PET-CT imaging, evidenced by the high association between those shape profiles and 18F-NaF uptake.

15.
J Hazard Mater ; 381: 120949, 2020 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-31387076

RESUMO

In this study we evaluated a new type of passive air sampler, the "mossphere" device, filled with a Sphagnum palustre clone. For this purpose, we compared the atmospheric levels of polyaromatic hydrocarbons (PAHs) collected using this device and those collected in conventional bulk deposition and particulate matter (PM10) samplers. All three types of samplers were exposed at 10 sites affected by different levels of pollution and located in two different climate zones. The bulk deposition/ mossphere comparison yielded a greater number of significant regressions with higher coefficients of determination than the PM10/ mossphere comparison. No significant regressions were observed for 3-ring PAHs in either comparison. The mosspheres explain ca. 50% of the variability of the concentrations of 4-, 5- and 6-ring PAHs and total PAHs detected in PM10 and ca. 70% of the corresponding concentrations detected in the bulk deposition. The use of the Sphagnum clone enables standardization of the set-up, thus making the mossphere device a good sampling tool for monitoring 4-, 5- and 6-ring and total PAHs, especially those associated with bulk deposition. The findings indicate the potential usefulness of this innovative technology for mapping PAH levels.

16.
Sci Total Environ ; 706: 136082, 2020 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-31855645

RESUMO

The active biomonitoring technique has been demonstrated to be an excellent tool for monitoring water quality; however, further improvement of the protocol is urgently needed. The present study was carried out to determine the best options for various methodological aspects of monitoring some metals and metalloids (i.e. Al, As, Cd, Co, Cu, Fe, Hg, Ni, Zn and Pb): i) the type of transplant, ii) pre-exposure washing (with or without cellular extractants), iii) the ratio between moss weight and bag surface area, and iv) the depth at which the bags are exposed. The importance of the different methodological aspects in the outcome of biomonitoring studies was also assessed by considering the results of the present and other previously published studies. Regarding the type of transplant, the traditionally used net bags were the best option for enclosing the moss; in addition, washing the moss with extracellular extractants (i.e. EDTA) prior to exposure increased the sensitivity of the technique and reduced the required exposure time (i.e. one week). For the amount of moss packed in each bag, a ratio of 12.5 mg cm-2 was the best choice. Finally, the depth at which the transplants were exposed did not affect pollutant accumulation (in shallow rivers, reservoirs or dams). Pollutant concentrations were also not affected by the existence of thermocline in deep waters during warmer months. Different methodological aspects involved in applying this technique determine the final concentrations of metals in moss. Although the influence of those was variable, for most elements (i.e. As, Cd, Co, Cu, Hg, Pb, Zn) 80% of the total variance was explained by 3-4 aspects, being species selection, devitalization treatment, duration of exposure, and number of transplants exposed the most important.

17.
Chemosphere ; : 125396, 2019 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-31784183

RESUMO

The resulting solutions from the cotton fabrics dyeing using the trichromy Procion HEXL, with NaCl as electrolyte, were electrochemically treated. These dyes have two azo groups as chromophores and two monochlorotriazinic groups as reactive groups in their structure. The combined oxidation/reduction at 125 mA cm-2 in a filter-press cell without compartment separation was carried out using an anode of Ti/SnO2-Sb-Pt and a cathode of stainless steel. This procedure has been effective in previous experiments using sulphate as electrolyte. A significant decrease in total organic carbon (TOC), chemical oxygen demand (COD), and total nitrogen (TN) was obtained. Moreover, the process took place efficiently. The average oxidation state (AOS) and the carbon oxidation state (COS) data confirmed the presence of stable oxidized intermediates in the electrolysed solution. The chromatography and the UV-Visible spectrophotometry assays indicated that full decolourisation is obtained at a loaded charge of around 0.81 Ah L-1 which is associated with an electrical energy per order (EEO) of 1.20 kWh m-3.

18.
Int J Numer Method Biomed Eng ; : e3296, 2019 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-31833669

RESUMO

Minimal mathematical models were developed to describe the electrophysiological properties of human δ-cells. Markov models of single channels were first developed based on the analysis of electrophysiological data. Monte Carlo simulations of voltage-clamp experiments were performed in an iteratively optimization procedure to estimate the number of channels required to reproduce the main characteristics of the macroscopic currents recorded experimentally. A membrane model of the firing of action potentials was then developed based on the kinetic schemes of single channels and the number of channels estimated. We showed that macroscopic currents of human δ-cells can be reproduced by minimal models of single channels when the appropriate number of channels is considered. In addition, our simulations suggest that human δ-cells are capable of generating action potentials through the interaction of the ionic currents involved. Finally, we determined the relative contribution of the currents underlying the firing of action potentials in human pancreatic δ-cells, which allowed us to propose a qualitative model of an action potential in terms of the underlying ionic currents.

19.
Med Intensiva ; 2019 Dec 10.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-31836259

RESUMO

OBJECTIVE: Endovascular techniques have become an essential tool for the treatment of descending thoracic aortic disease (thoracic endovascular aneurysm repair [TEVAR]). The aim is to analyze the indications and outcomes of emergency TEVAR at national level in relation to elective surgery. STUDY DESIGN AND SCOPE: A retrospective multicenter registry of patients with descending thoracic aortic disease treated on an emergency basis using endovascular techniques between 2012-2016, in 11 clinical units. PATIENTS, INCLUSION CRITERIA: 1) Ruptured descending thoracic aortic aneurysms; 2) Blunt traumatic thoracic aortic injury; and 3) Complicated acute type B aortic dissections (TBADc). PRIMARY VARIABLES: Patient mortality, survival and reoperation rate. SECONDARY VARIABLES: Demographic data, cardiovascular risk factors, specific data by indication, technical resources and postoperative complications. RESULTS: A total of 135 urgent TEVARs were included (111 men, mean age 60.4 ± 16.3 years): 43 ruptured thoracic aortic aneurysms (31.9%), 54 type B dissections (40%) and 32 traumatic aortic injuries (23.7%), and other etiologies 4.4%. The overall mortality rate at 30 days was 18.5%, and proved higher in the ruptured descending thoracic aortic aneurysms group (27.9%). The mean actuarial survival rate was 67± 6% at 5 years. The postoperative stroke rate was 5.2%, and the paraplegia rate was 5.9%. Aortic reoperations proved necessary in 12 patients (9%). CONCLUSIONS: Emergency descending thoracic aortic diseases can be treated by endovascular techniques with optimal results and low morbidity and mortality - though the figures are slightly higher than in elective cases. This registry provides, for the first time, real information on the daily clinical practice of emergency TEVAR in Spain.

20.
Artigo em Inglês | MEDLINE | ID: mdl-31667655

RESUMO

Knowledge of subject-specific muscle volumes may be used as surrogates for evaluating muscle strength and power generated by 'fat-free' muscle mass. This study presents population-based statistical learning approaches for predicting 'fat-free' muscle volume from known anthropometric measurements. Using computed tomography (CT) imaging data to obtain lower-limb muscle volumes from 50 men and women, this study evaluated six statistical learning methods for predicting muscle volumes from anthropometric measurements: (i) stepwise regression, (ii) linear support vector machine (SVM), (iii) 2nd-order polynomial SVM, (iv) linear partial least squares regression (PLSR), (v) quadratic PLSR, and (vi) 3rd-order spline fit PLSR. These techniques have successfully been demonstrated in bioengineering applications and freely available in open-source toolkits. Analysis revealed that separating a general population into sexes and/or cohorts based on adipose level may improve prediction accuracies. The most important measures that statistically influence muscle volume predictions were shank girth, followed by sex and finally leg length, as identified using stepwise regression. SVM learning predicted muscle volume with an accuracy of 85 ± 4% when using linear interpolation, but performed poorly with an accuracy of 59 ± 6% using polynomial interpolation. The simpler linear PLSR exhibited muscle volume prediction accuracy of 87 ± 2%, while quadratic PLSR was slightly reduced at 82 ± 3%. For the spline fit PLSR, high accuracy was observed on the training data set (~ 99%) but over-fitting (a drawback of high-interpolation methods) resulted in erroneous predictions on testing data, and hence, the model was deemed unsuitable. In conclusion, use of linear PLSR models with variables of sex, leg length, and shank girth is a useful tool for predicting 'fat-free' muscle volume.

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