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1.
Plant Biol (Stuttg) ; 2024 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-39250313

RESUMO

Coastal dunes are characterised by strong gradients of abiotic stress, typically increasing in severity from inland areas towards the shoreline. Thus, dune gradients represent unique opportunities to study intraspecific responses to environmental changes and to investigate which factors drive community change. This study aims to examine functional trait variation in two coexisting species in response to environmental changes along a dune gradient in NW Spain. Trait convergence was also investigated and compared between both ends of the gradient. We measured functional leaf traits related to plant efficiency in the use of light, water and nutrients, also possible stressors (salt content and pH) and availability of limiting resources (water and nutrients) in the soil. Most soil variables showed changes following a non-directional gradient. Differences in soil variables were site specific and depended on growth of the study species. Structural and functional traits depended on species and/or plant position on the gradient, except for effective quantum yield of PSII and leaf δ15N. The pattern of variation was mostly directional for reflectance indices related to leaf physiology. Multivariate analyses showed significant interspecific differences in the set of traits they exhibited along positions in the gradient. Species also differed in the combination of traits selected under given environmental conditions. Coexisting species display a specific set of traits that reflects different strategies to environmental stress. Our study highlights the overly simplistic nature of some previous studies that assume dune gradients are monotonically directional, without considering that these gradients may be differentially modified by species activity.

5.
Med Intensiva (Engl Ed) ; 45(6): 354-361, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34294233

RESUMO

OBJECTIVE: There is controversy regarding the influence of humidification systems upon the incidence of respiratory infections associated to invasive mechanical ventilation (IMV). An evaluation was made of the differences in the incidence of pneumonia and tracheobronchitis associated to mechanical ventilation (VAP and VAT, respectively) with passive and active humidification. DESIGN: A retrospective pre-post quasi-experimental study was carried out. SETTING: A polyvalent ICU with 14 beds. PATIENTS: All patients connected to IMV for >48h during 2014 and 2016 were included. INTERVENTIONS: During 2014, passive humidification with an hygroscopic heat and moisture exchanger (HME) was used, while during 2016 active humidification with a heated humidifier (HH) and an inspiratory heated wire was used. Identical measures for the prevention of VAP were established (Zero Pneumonia Project). MAIN OUTCOME MEASURES: The incidence of VAP and VAT was estimated for 1000 days of IMV in both groups, and statistically significant differences were assessed using Poisson regression analysis. RESULTS: A total of 287 patients were included (116 with HME and 171 with HH). The incidence density of VAP per 1000 days of IMV was 5.68 in the HME group and 5.80 in the HH group (p=ns). The incidence density of VAT was 3.41 and 3.26 cases per 1000 days of VMI with HME and HH respectively (p=ns). The duration of IMV was identified as a risk factor for VAP. CONCLUSIONS: In our population, active humidification in patients ventilated for >48h was not associated to an increase in respiratory infectious complications.


Assuntos
Pneumonia , Respiração Artificial , Temperatura Alta , Humanos , Umidade , Estudos Retrospectivos
7.
Artigo em Inglês | MEDLINE | ID: mdl-33820765

RESUMO

The high interindividual variability in the pharmacokinetics (PK) of linezolid has been described, which results in an unacceptably high proportion of patients with either suboptimal or potentially toxic concentrations following the administration of a fixed regimen. The aim of this study was to develop a population pharmacokinetic model of linezolid and use this to build and validate alogorithms for individualized dosing. A retrospective pharmacokinetic analysis was performed using data from 338 hospitalized patients (65.4% male, 65.5 [±14.6] years) who underwent routine therapeutic drug monitoring for linezolid. Linezolid concentrations were analyzed by using high-performance liquid chromatography. Population pharmacokinetic modeling was performed using a nonparametric methodology with Pmetrics, and Monte Carlo simulations were employed to calculate the 100% time >MIC after the administration of a fixed regimen of 600 mg administered every 12 h (q12h) intravenously (i.v.). The dose of linezolid needed to achieve a PTA ≥ 90% for all susceptible isolates classified according to EUCAST was estimated to be as high as 2,400 mg q12h, which is 4 times higher than the maximum licensed linezolid dose. The final PK model was then used to construct software for dosage individualization, and the performance of the software was assessed using 10 new patients not used to construct the original population PK model. A three-compartment model with an absorptive compartment with zero-order i.v. input and first-order clearance from the central compartment best described the data. The dose optimization software tracked patients with a high degree of accuracy. The software may be a clinically useful tool to adjust linezolid dosages in real time to achieve prespecified drug exposure targets. A further prospective study is needed to examine the potential clinical utility of individualized therapy.


Assuntos
Antibacterianos , Antibacterianos/uso terapêutico , Feminino , Humanos , Linezolida , Masculino , Método de Monte Carlo , Estudos Prospectivos , Estudos Retrospectivos
9.
Actas Urol Esp (Engl Ed) ; 44(3): 187-195, 2020 Apr.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-31843220

RESUMO

INTRODUCTION: Gleason score biopsy undergrading (GSBU) can have an impact on the management and prognosis of patients with prostate cancer. We analyze the possible impact of time and other clinical and analytical factors in the appearance of GSBU in our series. PATIENTS AND METHOD: Ambispective, multicenter study of 1955 patients with localized prostate cancer undergoing radical prostatectomy between 2005 and 2018. Descriptive statistics and hypothesis testing are reported by univariate and multivariate analyses. RESULTS: Mean age 63.69 (44-80) years, median PSA 8.70 ng / ml (1.23-99). GSBU was observed in 34.7% of the entire cohort. In 72.8% of the cases, the GSBU occurred in one consecutive Gleason score, with the progression from 3 + 3 to 3 + 4 being the most frequent (289 patients, 47.6%). Performing radical prostatectomy 90-180 days before or after the biopsy does not have an impact on its undergrading in any of the groups. In the univariate and multivariate analysis, the presence of tumor or pathological rectal examination in both lobes, the tumor load ≥50% of cylinders and a DPSA ≥0.20, showed independent discriminative capacity to select patients who presented GSBU. CONCLUSIONS: The time from biopsy to radical prostatectomy did not show impact on GSBU. The number of affected cylinders, bilateral tumor and DPSA are easily accessible parameters that can help us select patients with greater probability of presenting GSBU.


Assuntos
Próstata/patologia , Prostatectomia , Neoplasias da Próstata/patologia , Neoplasias da Próstata/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Biópsia , Humanos , Masculino , Pessoa de Meia-Idade , Gradação de Tumores , Estudos Prospectivos , Prostatectomia/métodos , Estudos Retrospectivos , Fatores de Tempo , Tempo para o Tratamento
10.
Water Sci Technol ; 80(7): 1287-1294, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31850880

RESUMO

Many rural areas of Latin America and the Caribbean (LAC) region are economically depressed. Rural sewage treatment in most areas of LAC is deficient or non-existent. Consequently, the possibility of generating economic revenue from treated sewage is an attractive option for deprived areas of developing countries. Given its peculiar characteristics, rural sewage may be coupled with biological systems such as algae for nutrient cycling. Acceptable algae growth and nutrient elimination were obtained from rural sewage whose treatment may have fallen short of current disposal standards. In this study, aerobic systems working on an 8-month cycle at three different volumetric loading rates (Bv) were assessed in relation to the lifetime growth of three algae strains native to Ecuador. Results indicate Chlorella sp. M2 as the optimal algal strain, with the highest growth rate at Bv of 1 g COD L-1 d- 1 and a removal of organic-N (30%), PO4 3--P (87%) and NH4 +-N (95%). Concomitantly, the kinetic constants of the sewage resulted in a low biomass yield coefficient, making the proposed system highly suitable for developing countries. Finally, the proposed partial recovery stream method, combining nutrient recovery with economic resource generation, appears to contain great potential.


Assuntos
Chlorella , Esgotos , Biomassa , Reatores Biológicos , Equador , Nitrogênio , Eliminação de Resíduos Líquidos
11.
Artigo em Inglês | MEDLINE | ID: mdl-31061150

RESUMO

A two-compartment pharmacokinetic (PK) population model of anidulafungin was fitted to PK data from 23 critically ill patients (age, 65 years [range, 28 to 81 years]; total body weight [TBW], 75 kg [range, 54 to 168 kg]). TBW was associated with clearance and incorporated into a final population PK model. Simulations suggested that patients with higher TBWs had less-extensive MIC coverage. Dosage escalation may be warranted in patients with high TBWs to ensure optimal drug exposures for treatment of Candida albicans and Candida glabrata infections.


Assuntos
Anidulafungina/farmacocinética , Antifúngicos/farmacocinética , Candidíase/tratamento farmacológico , Estado Terminal/terapia , Adulto , Idoso , Idoso de 80 Anos ou mais , Anidulafungina/administração & dosagem , Anidulafungina/uso terapêutico , Antifúngicos/administração & dosagem , Antifúngicos/uso terapêutico , Peso Corporal , Candida albicans/efeitos dos fármacos , Candida glabrata/efeitos dos fármacos , Feminino , Humanos , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Modelos Biológicos
14.
Nat Commun ; 9(1): 4214, 2018 10 11.
Artigo em Inglês | MEDLINE | ID: mdl-30310072

RESUMO

The quantum-confined Stark effect (QCSE) is an established optical modulation mechanism, yet top-performing modulators harnessing it rely on costly fabrication processes. Here, we present large modulation amplitudes for solution-processed layered hybrid perovskites and a modulation mechanism related to the orientational polarizability of dipolar cations confined within these self-assembled quantum wells. We report an anomalous (blue-shifting) QCSE for layers that contain methylammonium cations, in contrast with cesium-containing layers that show normal (red-shifting) behavior. We attribute the blue-shifts to an extraordinary diminution in the exciton binding energy that arises from an augmented separation of the electron and hole wavefunctions caused by the orientational response of the dipolar cations. The absorption coefficient changes, realized by either the red- or blue-shifts, are the strongest among solution-processed materials at room temperature and are comparable to those exhibited in the highest-performing epitaxial compound semiconductor heterostructures.

17.
Actas Urol Esp (Engl Ed) ; 42(9): 593-599, 2018 Nov.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-29292039

RESUMO

OBJECTIVE: To determine the actual incidence of prostate cancer (PC) in the healthcare areas of Castilla-Leon in 2014. MATERIAL AND METHODS: A multicentre study was conducted with the participation of 7 of the 9 healthcare areas of Castilla-Leon. We collected retrospective data that included 87.8% of the target population (men diagnosed with PC with histopathological confirmation in 2014). We calculated the raw and age-adjusted incidence rates based on the direct method and consulted the community and national epidemiological data in the Spanish National Institute of Statistics. RESULTS: A total of 1198 new cases of PC were diagnosed, with a raw incidence rate in the community of 109.54 cases per 100,000 men. The adjusted rates for the Spanish and European populations were 115.41 and 110.07, respectively. The age group with the highest diagnostic concentration was the 60-70-year group, with 41.97% of the diagnoses. The group with the highest incidence was the 70-80-year group, with 438.87 cases per 100,000 inhabitants. There were differences in the raw and age-adjusted incidence rates and in the age at diagnosis among the various included healthcare areas. CONCLUSIONS: The community raw incidence rate was higher than most existing data. We observed significant differences among the various geographical areas, which could be explained mainly by the age distribution and the opportunistic screening policies for each area.


Assuntos
Neoplasias da Próstata/epidemiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Área Programática de Saúde , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Sistema de Registros , Espanha/epidemiologia
18.
Food Chem ; 240: 686-693, 2018 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-28946330

RESUMO

The objective of this study was to develop a method for authenticating organic milk samples in North Spain on the basis of its trace mineral composition. Fourteen elements in 98 samples were determined by inductively coupled plasma mass spectrometry. Although concentrations of Co, Cr, Cu, I, Se and Zn where statistically higher in conventional milk and As in organic, none of these elements by itself was able to discriminate between organic and conventional milk. The chemical data was examined by principal component analysis and cluster analysis, revealing a natural separation between organic and conventional milk. In a second step, several supervised pattern recognition techniques were used to construct mathematical models for predicting the type of milk (organic or conventional) based on the metal content. The results proved that the model constructed using the artificial neural network is capable of correctly identifying the type of milk in almost 95% of cases.


Assuntos
Leite , Animais , Espectrometria de Massas , Análise de Componente Principal , Espanha , Oligoelementos
20.
Animal ; 12(6): 1296-1305, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29103395

RESUMO

The present study aimed to evaluate trace mineral status of organic dairy herds in northern Spain and the sources of minerals in different types of feed. Blood samples from organic and conventional dairy cattle and feed samples from the respective farms were analysed by inductively coupled plasma mass spectrometry to determine the concentrations of the essential trace elements (cobalt (Co), chromium (Cr), copper (Cu), iron (Fe), iodine (I), manganese (Mn), molybdenum (Mo), nickel (Ni), selenium (Se) and zinc (Zn)) and toxic trace elements (arsenic (As), cadmium (Cd), mercury (Hg) and lead (Pb)). Overall, no differences between organic and conventional farms were detected in serum concentrations of essential and toxic trace elements (except for higher concentrations of Cd on the organic farms), although a high level of inter-farm variation was detected in the organic systems, indicating that organic production greatly depends on the specific local conditions. The dietary concentrations of the essential trace elements I, Cu, Se and Zn were significantly higher in the conventional than in the organic systems, which can be attributed to the high concentration of these minerals in the concentrate feed. No differences in the concentrations of trace minerals were found in the other types of feed. Multivariate chemometric analysis was conducted to determine the contribution of different feed sources to the trace element status of the cattle. Concentrate samples were mainly associated with Co, Cu, I, Se and Zn (i.e. with the elements supplemented in this type of feed). However, pasture and grass silage were associated with soil-derived elements (As, Cr, Fe and Pb) which cattle may thus ingest during grazing.


Assuntos
Bovinos , Estado Nutricional , Agricultura Orgânica , Oligoelementos , Animais , Bovinos/fisiologia , Cobre , Indústria de Laticínios , Suplementos Nutricionais , Espanha , Zinco
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