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1.
Analyst ; 2024 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-38912921

RESUMO

3D printing has attracted the interest of researchers due to its creative freedom, low cost, and ease of operation. Because of these features, this technology has produced different types of electroanalytical platforms. Despite their popularity, the thermoplastic composites used for electrode fabrication typically have high electrical resistance, resulting in devices with poor electrochemical performance. Herein, we propose a new strategy to improve the electrochemical performance of 3D-printed electrodes and to gain chemical selectivity towards glucose detection. The approach involves synthesising a nanostructured gold film using an infrared laser source directly on the surface of low-contact resistance 3D-printed electrodes. The laser parameters, such as power, focal distance, and beam scan rate, were carefully optimised for the modification steps. Scanning electronic microscopy and energy-dispersive X-ray spectroscopy confirmed the morphology and composition of the nanostructured gold film. After modification, the resulting electrodes were able to selectively detect glucose, encouraging their use for sensing applications. When compared with a gold disc electrode, the gold-modified 3D-printed electrode provided a 44-fold current increase for glucose oxidation. As proof of concept, the devices were utilised for the non-enzymatic catalytic determination of glucose in drink samples, demonstrating the gold film's catalytic nature and confirming the analytical applicability with more precise results than commercial glucometers.

2.
J Appl Microbiol ; 135(1)2024 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-38148145

RESUMO

AIMS: To evaluate the antifungal and antibiofilm activity of gallic acid derivatives TPP+-C10 and TPP+-C12 and their effects on mitochondrial function on two Candida albicans reference strains (ATCC 90029 and ATCC 10231). METHODS AND RESULTS: First, we determined minimal inhibitory concentration (MIC) using a microdilution assay. Both compounds exerted antifungal effects, and their MICs ranged from 3.9 to 13 µM, with no statistically significant differences between them (P > 0.05, t-test). These concentrations served as references for following assays. Subsequently, we measured oxygen consumption with a Clark electrode. Our observations revealed that both drugs inhibited oxygen consumption in both strains with TPP+-C12 exerting a more pronounced inhibitory effect. We then employed flow cytometry with TMRE as a probe to assess mitochondrial membrane potential. For each strain assayed, the compounds induced a decay in transmembrane potential by 75%-90% compared to the control condition (P < 0.05, ANOVA). Then, we measured ATP levels using a commercial kit. TPP+-C12 showed a 50% decrease of ATP content (P < 0.05 ANOVA), while TPP+-C10 exhibited a less pronounced effect. Finally, we assessed the antibiofilm effect using the MTT reduction assay. Both compounds were effective, but TPP+-C12 displayed a greater potency, requiring a lower concentration to inhibit 50% of biofilms viability (P < 0.05, t-test). CONCLUSIONS: Derivatives of gallic acid linked to a TPP+ group exert antifungal and antibiofilm activity through impairment of mitochondrial function in C. albicans.


Assuntos
Antifúngicos , Candida albicans , Antifúngicos/farmacologia , Ácido Gálico/farmacologia , Testes de Sensibilidade Microbiana , Biofilmes , Mitocôndrias , Trifosfato de Adenosina
3.
Proc Natl Acad Sci U S A ; 118(49)2021 12 07.
Artigo em Inglês | MEDLINE | ID: mdl-34845017

RESUMO

One-third of all Neotropical forests are secondary forests that regrow naturally after agricultural use through secondary succession. We need to understand better how and why succession varies across environmental gradients and broad geographic scales. Here, we analyze functional recovery using community data on seven plant characteristics (traits) of 1,016 forest plots from 30 chronosequence sites across the Neotropics. By analyzing communities in terms of their traits, we enhance understanding of the mechanisms of succession, assess ecosystem recovery, and use these insights to propose successful forest restoration strategies. Wet and dry forests diverged markedly for several traits that increase growth rate in wet forests but come at the expense of reduced drought tolerance, delay, or avoidance, which is important in seasonally dry forests. Dry and wet forests showed different successional pathways for several traits. In dry forests, species turnover is driven by drought tolerance traits that are important early in succession and in wet forests by shade tolerance traits that are important later in succession. In both forests, deciduous and compound-leaved trees decreased with forest age, probably because microclimatic conditions became less hot and dry. Our results suggest that climatic water availability drives functional recovery by influencing the start and trajectory of succession, resulting in a convergence of community trait values with forest age when vegetation cover builds up. Within plots, the range in functional trait values increased with age. Based on the observed successional trait changes, we indicate the consequences for carbon and nutrient cycling and propose an ecologically sound strategy to improve forest restoration success.


Assuntos
Conservação dos Recursos Naturais , Florestas , Modelos Biológicos , Clima Tropical
4.
Mikrochim Acta ; 191(7): 396, 2024 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-38877161

RESUMO

The development of a portable analytical procedure is described for rapid sequential detection and quantification of the explosives 2,4,6-trinitrotoluene (TNT) and cyclotrimethylenetrinitramine (RDX) in forensic samples using a graphite sheet (GS). A single GS platform works as a collector of explosive residues and detector after its assembly into a 3D-printed cell. The detection strategy is based on cyclic square-wave stripping voltammetry. The cathodic scan from + 0.1 to -1.0 V with accumulation at 0.0 V enables the TNT detection (three reduction peaks), and the anodic scan from + 0.2 to + 1.55 V with accumulation at -0.9 V provides the RDX detection (two oxidation processes). Low detection limit values (0.1 µmol L-1 for TNT and 2.4 µmol L-1 for RDX) and wide linear ranges (from 1 to 150 µmol L-1 for TNT and from 20 to 300 µmol L-1 for RDX) were obtained. The sensor did not respond to pentaerythritol tetranitrate (PETN), which was evaluated as a potential interferent, because plastic explosives contain mixtures of TNT, RDX, and PETN. The GS electrode was also evaluated as a collector of TNT and RDX residues spread on different surfaces to simulate forensic scenarios. After swiping over different surfaces (metal, granite, wood, cloths, hands, money bills, and cellphone), the GS electrode was assembled in the 3D-printed cell ready to measure both explosives by the proposed method. In all cases, the presence of TNT and RDX was confirmed, attesting the reliability of the proposed device to act as collector and sensor.

5.
Proc Biol Sci ; 290(1990): 20222203, 2023 01 11.
Artigo em Inglês | MEDLINE | ID: mdl-36629117

RESUMO

Abandonment of agricultural lands promotes the global expansion of secondary forests, which are critical for preserving biodiversity and ecosystem functions and services. Such roles largely depend, however, on two essential successional attributes, trajectory and recovery rate, which are expected to depend on landscape-scale forest cover in nonlinear ways. Using a multi-scale approach and a large vegetation dataset (843 plots, 3511 tree species) from 22 secondary forest chronosequences distributed across the Neotropics, we show that successional trajectories of woody plant species richness, stem density and basal area are less predictable in landscapes (4 km radius) with intermediate (40-60%) forest cover than in landscapes with high (greater than 60%) forest cover. This supports theory suggesting that high spatial and environmental heterogeneity in intermediately deforested landscapes can increase the variation of key ecological factors for forest recovery (e.g. seed dispersal and seedling recruitment), increasing the uncertainty of successional trajectories. Regarding the recovery rate, only species richness is positively related to forest cover in relatively small (1 km radius) landscapes. These findings highlight the importance of using a spatially explicit landscape approach in restoration initiatives and suggest that these initiatives can be more effective in more forested landscapes, especially if implemented across spatial extents of 1-4 km radius.


Assuntos
Ecossistema , Florestas , Biodiversidade , Árvores , Plantas
6.
Acta Paediatr ; 112(3): 417-423, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36515614

RESUMO

AIM: To describe the trends in the delivery room approach and survival of extremely premature infants over the past two decades. METHODS: Time-series analysis of infants included in the Spanish SEN1500 network from 2004 to 2019. Patients born from 22 + 0 to 26 + 6 weeks were included. The primary outcome was an active approach in the delivery room. Survival and temporal trends were also studied. RESULTS: The study population included 8284 patients. At 22 and 23 weeks, an active approach was followed in 41.4% and 80.8%. A temporal trend toward a more active approach was observed at 23 weeks. Antenatal steroids were administered in 19.6% and 58.1% at 22 and 23 weeks. From 24 weeks, an active approach was applied in nearly all cases throughout the period, and more than 80% of patients received antenatal steroids. The rates of survival after an active approach were 8.7%, 21.6%, 40.6%, 59.9%, and 74.7% at 22, 23, 24, 25, and 26 weeks and significantly increased over the period, except for infants born at 22 weeks. CONCLUSION: Active management and survival of infants born from 23 weeks increased over the period, but the frequency of antenatal steroid administration was lower than the intention to resuscitate.


Assuntos
Salas de Parto , Lactente Extremamente Prematuro , Recém-Nascido , Humanos , Lactente , Gravidez , Feminino , Espanha/epidemiologia , Idade Gestacional , Mortalidade Infantil , Esteroides
7.
Eur Arch Otorhinolaryngol ; 280(12): 5267-5276, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37266755

RESUMO

PURPOSE: To analyze the psychometric properties of the Niigata Questionnaire (NPQ) for use in a European population with persistent postural-perceptual dizziness (PPPD). METHODS: Observational study included 140 patients with different vestibular conditions. Construct validity, internal consistency and concurrent validity were analyzed. Intra-class correlation coefficient (ICC), standard error of measurement (SEM) and minimal detectable change (MDC) were calculated. Receiver operating characteristic (ROC) curve was used to test diagnostic values. RESULTS: Of the 140 patients, 47 had a diagnosis of PPPD. Factorial analysis showed a single-factor structure and concurrent validity analysis showed strong correlations with other instruments. Cronbach alpha coefficients of 0.938 for the total score, 0.869 for the standing and gait subscale, 0.803 for the subscale of movements and 0.852 for the visual stimulation subscale were obtained. The reproducibility was substantial except for the standing subscale, which could be considered moderate. For the standing, movement and visual stimulation subscales and for the total score, the SEM was 3.27, 2.41, 2.50 and 6.63, respectively, and the MDC was 6.40, 4.72, 4.91 and 12.99, respectively. The NPQ total score showed an area under the curve (AUC) of 0.661, a sensitivity of 72.34 and a specificity of 55.91 for discriminating between PPPD and other vestibular disorders. CONCLUSIONS: The NPQ is feasible for use in a Western population and presents a uni-factorial structure, high internal consistency and strong correlation with other instruments. The reliability can be considered substantial. The NPQ has low accuracy in discriminating between subjects with or without PPPD.


Assuntos
Tontura , Doenças Vestibulares , Humanos , Tontura/diagnóstico , Reprodutibilidade dos Testes , Doenças Vestibulares/diagnóstico , Psicometria , Inquéritos e Questionários
8.
Mikrochim Acta ; 190(8): 297, 2023 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-37460848

RESUMO

A new electrochemical device fabricated by the combination of 3D printing manufacturing and laser-generated graphene sensors is presented. Cell and electrodes were 3D printed by the fused deposition modeling (FDM) technique employing acrylonitrile butadiene styrene filament (insulating material that composes the cell) and conductive filament (lab-made filament based on graphite dispersed into polylactic acid matrix) to obtain reference and auxiliary electrodes. Infrared-laser engraved graphene, also reported as laser-induced graphene (LIG), was produced by laser conversion of a polyimide substrate, which was assembled in the 3D-printed electrochemical cell that enables the analysis of low volumes (50-2000 µL). XPS analysis revealed the formation of nitrogen-doped graphene multilayers that resulted in excellent electrochemical sensing properties toward the detection of atropine (ATR), a substance that was found in beverages to facilitate sexual assault and other criminal acts. Linear range between 5 and 35 µmol L-1, detection limit of 1 µmol L-1, and adequate precision (RSD = 4.7%, n = 10) were achieved using differential-pulse voltammetry. The method was successfully applied to beverage samples with recovery values ranging from 80 to 105%. Interference studies in the presence of species commonly found in beverages confirmed satisfactory selectivity for ATR sensing. The devices proposed are useful portable analytical tools for on-site applications in the forensic scenario.

9.
Mikrochim Acta ; 190(10): 379, 2023 09 08.
Artigo em Inglês | MEDLINE | ID: mdl-37682352

RESUMO

Graphite sheet (GS) electrodes are flexible and versatile substrates for sensing electrochemical; however, their use has been limited to incorporate (bio)chemical modifiers. Herein, we demonstrated that a cold (low temperature) CO2 plasma treatment of GS electrodes provides a substantial improvement of the electrochemical activity of these electrodes due to the increased structural defects on the GS surface as revealed by Raman spectroscopy (ID/IG ratio), and scanning electron microscopy images. XPS analyses confirmed the formation of oxygenated functional groups at the GS surface after the plasma treatment that are intrinsically related to the substantial increase in the electron transfer coefficient (K0 values increased from 1.46 × 10-6 to 2.09 × 10-3 cm s-1) and with reduction of the resistance to charge transfer (from 129.8 to 0.251 kΩ). The improved electrochemical activity of CO2-GS electrodes was checked for the detection of emerging contaminant species, such as chloramphenicol (CHL), ciprofloxacin (CIP) and sulphanilamide (SUL) antibiotics, at around + 0.15, + 1.10 and + 0.85 V (versus Ag/AgCl), respectively, by square wave voltammetry. Limit of detection values in the submicromolar range were achieved for CHL (0.08 µmol L-1), CIP (0.01 µmol L-1) and SFL (0.11 µmol L-1), which enabled the sensor to be successfully applied to natural waters and urine samples (recovery values from 85 to 119%). The CO2-GS electrode is highly stable and inexpensive ($0.09 each sensor) and can be easily inserted in portable 3D printed cells for environmental on-site analyses.


Assuntos
Cloranfenicol , Grafite , Ciprofloxacina , Sulfanilamida , Dióxido de Carbono , Eletrodos
10.
Mikrochim Acta ; 190(2): 63, 2023 01 21.
Artigo em Inglês | MEDLINE | ID: mdl-36670263

RESUMO

The combination of CO2 laser ablation and electrochemical surface treatments is demonstrated to improve the electrochemical performance of carbon black/polylactic acid (CB/PLA) 3D-printed electrodes through the growth of flower-like Na2O nanostructures on their surface. Scanning electron microscopy images revealed that the combination of treatments ablated the electrode's polymeric layer, exposing a porous surface where Na2O flower-like nanostructures were formed. The electrochemical performance of the fabricated electrodes was measured by the reversibility of the ferri/ferrocyanide redox couple presenting a significantly improved performance compared with electrodes treated by only one of the steps. Electrodes treated by the combined method also showed a better electrochemical response for tyrosine oxidation. These electrodes were used as a non-enzymatic tyrosine sensor for quantification in human urine samples. Two fortified urine samples were analyzed, and the recovery values were 106 and 109%. The LOD and LOQ for tyrosine determination were 0.25 and 0.83 µmol L-1, respectively, demonstrating that the proposed devices are suitable sensors for analyses of biological samples, even at low analyte concentrations.


Assuntos
Terapia a Laser , Nanoestruturas , Humanos , Dióxido de Carbono , Nanoestruturas/química , Oxirredução , Impressão Tridimensional
11.
Int J Mol Sci ; 24(11)2023 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-37298656

RESUMO

Drug combinations are increasingly studied in the field of anticancer agents. Mathematical models, such as Loewe, Bliss, and HSA, are used to interpret drug combinations, while informatics tools help cancer researchers identify the most effective combinations. However, the different algorithms each software uses lead to results that do not always correlate. This study compared the performance of Combenefit (Ver. 2.021) and SynergyFinder (Ver. 3.6) in analyzing drug synergy by studying combinations involving non-steroidal analgesics (celecoxib and indomethacin) and antitumor drugs (carboplatin, gemcitabine, and vinorelbine) on two canine mammary tumor cell lines. The drugs were characterized, their optimal concentration-response ranges were determined, and nine concentrations of each drug were used to make combination matrices. Viability data were analyzed under the HSA, Loewe, and Bliss models. Celecoxib-based combinations showed the most consistent synergistic effect among software and reference models. Combination heatmaps revealed that Combenefit gave stronger synergy signals, while SynergyFinder produced better concentration-response fitting. When the average values of the combination matrices were compared, some combinations shifted from synergistic to antagonistic due to differences in the curve fitting. We also used a simulated dataset to normalize each software's synergy scores, finding that Combenefit tends to increase the distance between synergistic and antagonistic combinations. We conclude that concentration-response data fitting biases the direction of the combination (synergistic or antagonistic). In contrast, the scoring from each software increases the differences among synergistic or antagonistic combinations in Combenefit when compared to SynergyFinder. We strongly recommend using multiple reference models and reporting complete data analysis for synergy claiming in combination studies.


Assuntos
Antineoplásicos , Animais , Cães , Celecoxib/farmacologia , Quimioterapia Combinada , Antineoplásicos/farmacologia , Software , Combinação de Medicamentos , Sinergismo Farmacológico , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia
12.
Int J Mol Sci ; 24(21)2023 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-37958767

RESUMO

The interaction of the activating transcription factor 6 (ATF6), a key effector of the unfolded protein response (UPR) in the endoplasmic reticulum, with the neuronal calcium sensor Downstream Regulatory Element Antagonist Modulator (DREAM) is a potential therapeutic target in neurodegeneration. Modulation of the ATF6-DREAM interaction with repaglinide (RP) induced neuroprotection in a model of Huntington's disease. Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disorder with no cure, characterized by the progressive loss of motoneurons resulting in muscle denervation, atrophy, paralysis, and death. The aim of this work was to investigate the potential therapeutic significance of DREAM as a target for intervention in ALS. We found that the expression of the DREAM protein was reduced in the spinal cord of SOD1G93A mice compared to wild-type littermates. RP treatment improved motor strength and reduced the expression of the ALS progression marker collagen type XIXα1 (Col19α1 mRNA) in the quadriceps muscle in SOD1G93A mice. Moreover, treated SOD1G93A mice showed reduced motoneuron loss and glial activation and increased ATF6 processing in the spinal cord. These results indicate that the modulation of the DREAM-ATF6 interaction ameliorates ALS symptoms in SOD1G93A mice.


Assuntos
Esclerose Lateral Amiotrófica , Camundongos , Animais , Camundongos Transgênicos , Esclerose Lateral Amiotrófica/tratamento farmacológico , Esclerose Lateral Amiotrófica/genética , Esclerose Lateral Amiotrófica/metabolismo , Fator 6 Ativador da Transcrição/genética , Fator 6 Ativador da Transcrição/metabolismo , Neuroproteção , Neurônios Motores/metabolismo , Proteínas Interatuantes com Canais de Kv/metabolismo , Superóxido Dismutase/genética , Superóxido Dismutase/metabolismo , Modelos Animais de Doenças
13.
Anal Chem ; 94(17): 6417-6429, 2022 05 03.
Artigo em Inglês | MEDLINE | ID: mdl-35348329

RESUMO

The 3D printing (or additive manufacturing, AM) technology is capable to provide a quick and easy production of objects with freedom of design, reducing waste generation. Among the AM techniques, fused deposition modeling (FDM) has been highlighted due to its affordability, scalability, and possibility of processing an extensive range of materials (thermoplastics, composites, biobased materials, etc.). The possibility of obtaining electrochemical cells, arrays, pieces, and more recently, electrodes, exactly according to the demand, in varied shapes and sizes, and employing the desired materials has made from 3D printing technology an indispensable tool in electroanalysis. In this regard, the obtention of an FDM 3D printer has great advantages for electroanalytical laboratories, and its use is relatively simple. Some care has to be taken to aid the user to take advantage of the great potential of this technology, avoiding problems such as solution leakages, very common in 3D printed cells, providing well-sealed objects, with high quality. In this sense, herein, we present a complete protocol regarding the use of FDM 3D printers for the fabrication of complete electrochemical systems, including (bio)sensors, and how to improve the quality of the obtained systems. A guide from the initial printing stages, regarding the design and structure obtention, to the final application, including the improvement of obtained 3D printed electrodes for different purposes, is provided here. Thus, this protocol can provide great perspectives and alternatives for 3D printing in electroanalysis and aid the user to understand and solve several problems with the use of this technology in this field.


Assuntos
Impressão Tridimensional , Protocolos Clínicos , Eletrodos
14.
Glob Chang Biol ; 28(17): 5254-5268, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35703577

RESUMO

Data capturing multiple axes of tree size and shape, such as a tree's stem diameter, height and crown size, underpin a wide range of ecological research-from developing and testing theory on forest structure and dynamics, to estimating forest carbon stocks and their uncertainties, and integrating remote sensing imagery into forest monitoring programmes. However, these data can be surprisingly hard to come by, particularly for certain regions of the world and for specific taxonomic groups, posing a real barrier to progress in these fields. To overcome this challenge, we developed the Tallo database, a collection of 498,838 georeferenced and taxonomically standardized records of individual trees for which stem diameter, height and/or crown radius have been measured. These data were collected at 61,856 globally distributed sites, spanning all major forested and non-forested biomes. The majority of trees in the database are identified to species (88%), and collectively Tallo includes data for 5163 species distributed across 1453 genera and 187 plant families. The database is publicly archived under a CC-BY 4.0 licence and can be access from: https://doi.org/10.5281/zenodo.6637599. To demonstrate its value, here we present three case studies that highlight how the Tallo database can be used to address a range of theoretical and applied questions in ecology-from testing the predictions of metabolic scaling theory, to exploring the limits of tree allometric plasticity along environmental gradients and modelling global variation in maximum attainable tree height. In doing so, we provide a key resource for field ecologists, remote sensing researchers and the modelling community working together to better understand the role that trees play in regulating the terrestrial carbon cycle.


Assuntos
Florestas , Árvores , Biomassa , Carbono/metabolismo , Ciclo do Carbono , Ecossistema , Árvores/fisiologia
15.
Paediatr Perinat Epidemiol ; 36(3): 329-336, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-34981845

RESUMO

BACKGROUND: Public health measures (PHM) designed to contain the spread of COVID-19 pandemic have influenced the epidemiological characteristics of other viral infections. Its impact on acute RSV bronchiolitis in infants of ≤24 months old has not been systematically studied in our setting. OBJECTIVES: To describe the monthly pattern of visits to the Paediatric Emergency Department (PED) of patients 0 to 14 years of age, the rate of patients diagnosed with RSV acute bronchiolitis per thousand inhabitants of 0 to 24 months, and the rate of them requiring hospital admission during the winter 2020-2021, in the context of local and national COVID-19 restrictions and compare them to the four previous seasons. METHODS: Interrupted time series analysis of patients assisted in the PED and diagnosed with or admitted for RSV acute bronchiolitis in a tertiary University Hospital from January 2016 to February 2020 (pre-intervention period) and from March 2020 to June 2021 (post-intervention period). INTERVENTION: Preventive PHM implemented by the Spanish government weighted by the Containment and Health Index of the Oxford COVID-19 Government Response Tracker. RESULTS: The intervention was followed by an immediate reduction of the rate of visits to the PED of -19.5 (95% confidence interval [CI] -24.0, -14.9) per thousand, and the rate of diagnoses and admissions for RSV acute bronchiolitis of -44.3 (95% CI -73.8, -14.8) and -1.4 (95% CI -2.7, -0.1) per thousand, respectively, with a delayed rebound. CONCLUSIONS: After the implementation of PHM to prevent the spread of SARS-CoV-2 infection, an immediate and important decline in the visits to the PED was observed, with an upward change thereafter. There was also an initial reduction in the diagnoses of and admissions by RSV acute bronchiolitis. An upward trend was observed six to nine months after the usual time of the winter RSV epidemic, coinciding with the relaxation of the preventive PHM.


Assuntos
Bronquiolite , COVID-19 , Infecções por Vírus Respiratório Sincicial , Vírus Sincicial Respiratório Humano , Bronquiolite/epidemiologia , COVID-19/epidemiologia , COVID-19/prevenção & controle , Criança , Pré-Escolar , Humanos , Lactente , Recém-Nascido , Análise de Séries Temporais Interrompida , Pandemias/prevenção & controle , Saúde Pública , Infecções por Vírus Respiratório Sincicial/epidemiologia , Infecções por Vírus Respiratório Sincicial/prevenção & controle , SARS-CoV-2 , Estações do Ano
16.
Anal Bioanal Chem ; 414(18): 5309-5318, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33890118

RESUMO

In this work, the batch injection analysis system with amperometric detection using reduced graphene oxide as a modifier of glassy carbon electrode (GCE) was investigated for the simple, fast, and sensitive monitoring of levofloxacin (LEVO) and ciprofloxacin (CIPRO) in samples of pharmaceutical formulations, synthetic urine, and milk (low- and high-fat content). LEVO and CIPRO were quantified in seven samples using amperometric measurements at +1.10 V vs Ag/AgCl, KCl(sat). The developed methods showed excellent analytical performance with limits of detection of 0.30 and 0.16 µmol L-1, linear range from 3.0 to 50 µmol L-1 and 1.0 to 50 µmol L-1, relative standard deviation below 9.7 and 3.1%, and recovery ranges ranging from 80 to 107% and from 78 to 109% for LEVO and CIPRO, respectively. In addition, the minimum sample preparation (simple dilution) combined with a high analytical frequency (130 to 180 analyses per hour) can be highlighted. Thus, the methods are promising for implementation in routine analysis and quality control to different samples.


Assuntos
Carbono , Fluoroquinolonas , Animais , Carbono/análise , Ciprofloxacina/análise , Composição de Medicamentos , Eletrodos , Fluoroquinolonas/análise , Grafite , Leite/química
17.
Nature ; 530(7589): 211-4, 2016 02 11.
Artigo em Inglês | MEDLINE | ID: mdl-26840632

RESUMO

Land-use change occurs nowhere more rapidly than in the tropics, where the imbalance between deforestation and forest regrowth has large consequences for the global carbon cycle. However, considerable uncertainty remains about the rate of biomass recovery in secondary forests, and how these rates are influenced by climate, landscape, and prior land use. Here we analyse aboveground biomass recovery during secondary succession in 45 forest sites and about 1,500 forest plots covering the major environmental gradients in the Neotropics. The studied secondary forests are highly productive and resilient. Aboveground biomass recovery after 20 years was on average 122 megagrams per hectare (Mg ha(-1)), corresponding to a net carbon uptake of 3.05 Mg C ha(-1) yr(-1), 11 times the uptake rate of old-growth forests. Aboveground biomass stocks took a median time of 66 years to recover to 90% of old-growth values. Aboveground biomass recovery after 20 years varied 11.3-fold (from 20 to 225 Mg ha(-1)) across sites, and this recovery increased with water availability (higher local rainfall and lower climatic water deficit). We present a biomass recovery map of Latin America, which illustrates geographical and climatic variation in carbon sequestration potential during forest regrowth. The map will support policies to minimize forest loss in areas where biomass resilience is naturally low (such as seasonally dry forest regions) and promote forest regeneration and restoration in humid tropical lowland areas with high biomass resilience.


Assuntos
Biomassa , Florestas , Árvores/crescimento & desenvolvimento , Clima Tropical , Carbono/metabolismo , Ciclo do Carbono , Sequestro de Carbono , Ecologia , Umidade , América Latina , Chuva , Fatores de Tempo , Árvores/metabolismo
18.
Eur J Pediatr ; 181(5): 2067-2074, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35147746

RESUMO

The first hours after birth entail a window of opportunity to decrease morbidity and mortality among extremely preterm infants. The availability of staff and its tiredness vary depending on the timing and day of the week. We hypothesized that these circumstances may impact neonatal outcomes. We have conducted a multicenter cohort study with data obtained from the Spanish neonatal network database SEN1500, where staff doctors are in the house 24/7. The main study exposure was the time of birth; secondary exposures were cumulative work hours from the medical and nurses' shifts and day of the week. The primary outcome was survival to hospital discharge. Secondary outcomes included common preterm infants' in-hospital complications. Univariate and multivariate analysis adjusting for potential confounders was performed. All extremely preterm infants (N = 8798) born between 2011 and 2019 were eligible; 35.7% of them were admitted during the night shift. No differences were found between day and night births regarding survival or morbidity. No differences were found between weekdays and weekends or when considering cumulative worked hours in the shifts. Infants born during the night shift were more likely to be intubated at birth (OR 1.20, CI95% 1.06-1.37), receive surfactant (OR 1.24, CI95% 1.08-1.44), and having anemia requiring transfusion (OR 1.23, CI 95% 1.08-1.42). CONCLUSION: the time of birth did not seem to affect mortality and morbidity of extremely preterm infants. WHAT IS KNOWN: • The first hours after birth in extremely preterm infants are a very valuable opportunity to decrease mortality and morbidity. • Time and day of birth have long been linked to outcomes in preterm infants, with night shifts and weekends classically having higher rates of mortality and morbidity. WHAT IS NEW: • In this study, no differences were found between day and night births regarding survival or major morbidity. • Infants born during the night shift were more likely to be intubated at birth, receive surfactant and having anemia requiring transfusion.


Assuntos
Lactente Extremamente Prematuro , Doenças do Prematuro , Estudos de Coortes , Idade Gestacional , Humanos , Lactente , Mortalidade Infantil , Recém-Nascido , Espanha/epidemiologia , Tensoativos
19.
J Perinat Med ; 50(8): 1150-1156, 2022 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-35533646

RESUMO

OBJECTIVES: The Northern California Kaiser-Permanente Neonatal Sepsis Risk Calculator (SRC) has proved to be safe and effective in reducing laboratory tests, hospital admissions, and administration of antibiotics to patients at risk of early-onset neonatal sepsis (EONS). Many studies have focused on maternal chorioamnionitis as the principal risk factor for EONS. We wanted to know if the use of the SRC could be equally efficient in the context of several other infectious risk factors (IRF), in addition to chorioamnionitis, such as intrapartum maternal fever, GBS colonization and/or prolonged rupture of membranes (PROM). METHODS: Systematic study of neonates with ≥35 weeks gestational age (GA), born in our tertiary university hospital during a period of 18 months. Patients were retrospectively assessed with the SRC and its recommendations were compared with the actual management. A bivariate analysis of perinatal interventions, and outcomes was performed. RESULTS: A total of 5,885 newborns were born during the study period and 1783 mothers (31%) had at least one IRF. The incidence of culture-proven EONS was 0.5‰. The use of the SRC would have reduced laboratory evaluations (CBC and CRP) from 56.2 to 23.3%, and blood cultures, hospital admissions and antibiotic therapy from 22.9 to 15.5%, 17.8 and 7.6%, respectively. The management based on patients' symptoms would have shown a reduction to 7.5% in all the outcomes of interest. CONCLUSIONS: Both, the SRC and the management based on clinical findings, are safe and efficient to reduce the number of analytical studies, hospital admissions and administration of antibiotics to neonates with IRF.


Assuntos
Corioamnionite , Sepse Neonatal , Sepse , Antibacterianos/uso terapêutico , Corioamnionite/tratamento farmacológico , Corioamnionite/epidemiologia , Feminino , Idade Gestacional , Humanos , Recém-Nascido , Sepse Neonatal/diagnóstico , Sepse Neonatal/epidemiologia , Gravidez , Estudos Retrospectivos , Fatores de Risco
20.
Mikrochim Acta ; 189(2): 57, 2022 01 10.
Artigo em Inglês | MEDLINE | ID: mdl-35013813

RESUMO

Low oxidation stability is the main drawback of biodiesels and biokerosenes that is overcome by using antioxidants, which can be combined due to synergistic effects. This paper demonstrates that 3D-printed electrochemical devices can be applied to biofuel electroanalysis, including the monitoring of oxidation stability by quantifying the antioxidant content in biofuels. Fabrication requires 3D-printed acrylic templates at which a polylactic acid (PLA) filament with conducting carbon-black filling sensors is extruded by a 3D pen. The antioxidants butyl hydroxyanisole (BHA) and tert-butylhydroquinone (TBHQ) are the most employed additives in biodiesel production, and thus, their electrochemical behavior was investigated; 2,6-ditertbutylphenol (2,6-DTBP) was included in this investigation because it is commonly added to biokerosenes. The electrochemical surface treatment of the 3D-printed electrodes improved the current responses of all antioxidants; however, the electrochemical oxidation of TBHQ was clearly more affected by an electrocatalytic action shifting its oxidation towards less positive potentials (~200 mV), which resulted in a better separation of TBHQ and BHA oxidation peaks (+0.4 and +0.6 V vs Ag|AgCl, respectively). The oxidation of 2,6-DTBP occurred at more positive potentials (+1.2 V vs Ag|AgCl). The simultaneous determination of TBHQ and BHA by differential-pulse voltammetry resulted in linear responses in the range 0.5 and 175 µmol L-1 with limits of detection and quantification of 0.15 µmol L-1 and 0.5 µmol L-1, respectively. The presence of Fe3+, Cu2+, Pb2+, Mn2+, Cd2+, and Zn2+, even in high concentrations, did not interfere in the determination of TBHQ and BHA. The determination of 2,6-DTBP in biokerosene was achieved by cyclic voltammetry. All relative standard deviations (RSD) were lower than 6.0 %, indicating adequate precision of the methods. Spiked biofuel samples were analyzed (after dilution in electrolyte) and recovery values between 85 and 120% were obtained, which indicates absence of sample matrix effects.


Assuntos
Antioxidantes/química , Biocombustíveis/análise , Técnicas Eletroquímicas/instrumentação , Técnicas Eletroquímicas/métodos , Poliésteres/química , Estrutura Molecular , Impressão Tridimensional , Fuligem
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