192 research outputs found
Hybrid magnetic graphitic nanocomposites for catalytic wet peroxide oxidation applications
Fe3O4, with a lattice parameter a = 8.357 A and average particle size of 12.5 +/- 3.6 nm, was successfully encapsulated within a graphitic structure by a hierarchical co-assembly approach, followed by thermal annealing. The resulting material was denoted as MGNC-magnetic graphitic nanocomposite. MGNC possesses average core size of 109 +/- 35 nm (mainly composed by agglomerates of magnetic nanoparticles), stability up to 400 degrees C under oxidizing atmosphere, a micro-mesoporous structure with a fairly developed specific surface area (S-BET = 330 m(2) g(-1)) and neutral character (pH(PZC) = 7.1). Catalytic wet peroxide oxidation (CWPO) experiments performed with a 4-nitrophenol (4-NP)/Fe3O4 mass ratio fixed at 36.6, allowed to achieve high efficiency of catalyst usage throughout the wide range of 4-NP concentration considered (200 mg L-1-5 g L-1). The inclusion of Fe3O4 nanoparticles in a graphitic structure during the synthesis of MGNC was found to (i) enhance the catalytic activity in CWPO when compared to Fe3O4, due to increased adsorptive interactions between the surface of the catalyst and the pollutant molecules, while (ii) strongly limiting the leaching of Fe species from Fe3O4 to the treated water, due to the confinement effect caused by the carbon shell. As a result of these effects, unprecedented pollutant mass removals were obtained ranging from 5000 mg(-1) h(-1), when the CWPO process is performed with [4-NP](o) = 200 mg L-1 at pH = 3, to 1250 mgg(-1) h(-1), when [4-NP](o) = 5 g L-1. High efficiency of H2O2 consumption is obtained when MGNC is applied in the CWPO of 4 -NP solutions at pH = 3, with TOC removals per unit of H2O2 decomposed (n(H2O2)) in the range 64-100%. In addition, the MGNC catalyst is also active at pH = 6; in this case a pollutant mass removal of 2090 mg g(-1) h(-1) was obtained. Although MGNC partially deactivates through successive reusability cycles, the pollutant mass removal obtained at the end of the fourth cycle is still very high when 200 mg L-1 4-NP solutions are considered (4808 mg g(-1) h(-1), representing only a ca. 4% decrease when compared to the first cycle). A higher deactivation of the MGNC catalyst is observed when 5 gL(-1) 4-NP solutions are employed. Nevertheless, the pollutant mass removal obtained at the end of the third cycle is still high (551 mgg(-1) h(-1))
The NAC domain-containing protein, GmNAC6, is a downstream component of the ER stress- and osmotic stress-induced NRP-mediated cell-death signaling pathway
<p>Abstract</p> <p>Background</p> <p>The endoplasmic reticulum (ER) is a major signaling organelle, which integrates a variety of responses against physiological stresses. In plants, one such stress-integrating response is the N-rich protein (NRP)-mediated cell death signaling pathway, which is synergistically activated by combined ER stress and osmotic stress signals. Despite the potential of this integrated signaling to protect plant cells against different stress conditions, mechanistic knowledge of the pathway is lacking, and downstream components have yet to be identified.</p> <p>Results</p> <p>In the present investigation, we discovered an NAC domain-containing protein from soybean, GmNAC6 (<it>Glycine max </it>NAC6), to be a downstream component of the integrated pathway. Similar to <it>NRP-A </it>and <it>NRP-B, GmNAC6 </it>is induced by ER stress and osmotic stress individually, but requires both signals for full activation. Transient expression of <it>GmNAC6 </it>promoted cell death and hypersensitive-like responses <it>in planta</it>. <it>GmNAC6 </it>and <it>NRPs </it>also share overlapping responses to biotic signals, but the induction of <it>NRPs </it>peaked before the increased accumulation of GmNAC6 transcripts. Consistent with the delayed kinetics of <it>GmNAC6 </it>induction, increased levels of <it>NRP-A </it>and <it>NRP-B </it>transcripts induced promoter activation and the expression of the <it>GmNAC6 </it>gene.</p> <p>Conclusions</p> <p>Collectively, our results biochemically link GmNAC6 to the ER stress- and osmotic stress-integrating cell death response and show that GmNAC6 may act downstream of the NRPs.</p
Cost-Effectiveness of Haemorrhoidal Artery Ligation versus Rubber Band Ligation for the Treatment of Grade II–III Haemorrhoids: Analysis Using Evidence from the HubBLe Trial
Aim Haemorrhoids are a common condition, with nearly
30,000 procedures carried out in England in 2014/15, and
result in a significant quality-of-life burden to patients and
a financial burden to the healthcare system. This study
examined the cost effectiveness of haemorrhoidal artery
ligation (HAL) compared with rubber band ligation (RBL)
in the treatment of grade II–III haemorrhoids.
Method This analyses used data from the HubBLe study, a
multicentre, open-label, parallel group, randomised controlled
trial conducted in 17 acute UK hospitals between
September 2012 and August 2015. A full economic evaluation,
including long-term cost effectiveness, was conducted
from the UK National Health Service (NHS)
perspective. Main outcomes included healthcare costs,
quality-adjusted life-years (QALYs) and recurrence. Costeffectiveness
results were presented in terms of incremental
cost per QALY gained and cost per recurrence
avoided. Extrapolation analysis for 3 years beyond the trial
follow-up, two subgroup analyses (by grade of haemorrhoids
and recurrence following RBL at baseline), and
various sensitivity analyses were undertaken.
Results In the primary base-case within-trial analysis, the
incremental total mean cost per patient for HAL compared
with RBL was £1027 (95% confidence interval [CI] £782–
£1272, p\0.001). The incremental QALYs were 0.01
QALYs (95% CI -0.02 to 0.04, p = 0.49). This generated
an incremental cost-effectiveness ratio (ICER) of £104,427
per QALY. In the extrapolation analysis, the estimated
probabilistic ICER was £21,798 per QALY. Results from
all subgroup and sensitivity analyses did not materially
change the base-case result.
Conclusions Under all assessed scenarios, the HAL procedure
was not cost effective compared with RBL for the
treatment of grade II-III haemorrhoids at a cost-effectiveness
threshold of £20,000 per QALY; therefore
Fast polarization mechanisms in the uniaxial tungsten-bronze relaxor strontium barium niobate SBN-81
The high-frequency dielectric response of the uniaxial strontium barium niobate crystals with 81% of Sr has been studied from 1 kHz to 30 THz along the polar c axis by means of several techniques (far infrared, time domain terahertz, high-frequency and low-frequency dielectric spectroscopies) in a wide temperature interval 20–600 K. Relaxor properties were observed in the complex dielectric response and four main excitations were ascertained below the phonon frequencies. These fast polarization mechanisms take place at THz, GHz and MHz ranges and show different temperature evolution. The central mode excitation in the THz range, related to anharmonic dynamics of cations, slightly softens from high temperatures and then hardens below T ~ 400 K. Below the phase transition (at T ~ 330 K) an additional microwave excitation appears near 10 GHz related to micro domain wall oscillations. The strongest relaxation appears in the GHz range and slows down on cooling according to the Arrhenius law. Finally, another relaxation, present in the MHz range at high temperatures, also slows down on cooling at least to the kHz range. These two relaxations are due to polar fluctuations and nanodomains dynamics. Altogether, the four excitations explain the dielectric permittivity maximum in the kHz range
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Impact of the Health Gym Program on hospital admissions for stroke in the state of Pernambuco, Brazil
This study aimed to evaluate the impact of the Health Gym Program (HGP) on hospital admissions for stroke in the state of Pernambuco, Brazil. This policy impact evaluation used a quasi-experimental approach consisting of a difference-in-differences estimator, weighted by propensity score matching to deal with potential confounding variables. The study comprised socioeconomic, demographic, and epidemiological data from official Brazilian databases from 2010 to 2019. The treatment group was composed of the 134 municipalities that implemented the HGP since 2011. The 51 municipalities that did not were allocated to the comparison group. The nearest neighbor algorithm (N5) was used to pair treatment and comparison group municipalities and create the weights to evaluate the average treatment effect on the treated (ATT) in the difference-in-differences estimator. In 2010, 2,771 people were hospitalized for stroke (0.51% of all hospitalizations) and in 2019, 11,542 (2%). Municipalities that implemented the HGP had 18.37% fewer hospitalizations than their counterparts in the comparison group. The program’s impact in reducing hospitalization rates was incrementally greater among men (ATT: -0.1932) and those aged 71 to 80 years (ATT: -0.1911). All results were statistically significant at the 5% level. The HGP reduced hospitalization for stroke in several population groups, but primarily in those whose underlying prevalence of stroke is highest, reinforcing the importance of public investments in health promotion policies designed to encourage lifestyle changes.Resumo: O estudo teve como objetivo avaliar o impacto do Programa Academia da Saúde (PAS) nas internações hospitalares por acidente vascular cerebral (AVC) no Estado de Pernambuco, Brasil. Esta avaliação
de impacto das políticas utilizou uma abordagem quase-experimental que consiste em um estimador de diferença-em-diferenças, ponderado
pelo pareamento por escore de propensão para lidar com possíveis fatores de confusão. O estudo foi composto por dados socioeconômicos, demográficos e epidemiológicos de bases de dados oficiais brasileiras entre os anos de 2010 e 2019. O grupo de tratamento foi composto pelos 134 municípios que implantaram o PAS a partir de 2011, e os 51
municípios que não implantaram foram alocados no grupo de comparação. O algoritmo do vizinho mais próximo (N5) foi utilizado para emparelhar
os municípios tratados e comparar aos municípios do grupo controle, criando os pesos que foram utilizados para avaliar o efeito médio do tratamento sobre o tratado (ATT) no estimador de diferença-
-em-diferenças. Houve 2.771 internações por AVC em 2010 (0,51% de todas as internações) e 11.542 (2%) em 2019. Os municípios que implementaram o PAS tiveram 18,37% menos internações em comparação
com seus homólogos no grupo de comparação. O impacto do programa na redução das taxas de internação foi maior entre os homens (ATT: -0,1932) e naqueles com idade entre 71 e 80 anos (ATT: -0,1911). Todos os resultados foram estatisticamente significativos em um nível de 5%. O
PAS reduziu a hospitalização por AVC em vários grupos populacionais, mas principalmente naqueles em que a prevalência subjacente de AVC é mais alta, reforçando a importância dos investimentos públicos em políticas de promoção da saúde destinadas a estimular mudanças nos estilos de vida.
Avaliação de Programas e Projetos de Saúde;
Doença Crônica; Promoção da Saúde; Pontuação
de Propensão; Acidente Vascular CerebralResumen: El objetivo de este trabajo es evaluar el impacto del Programa Academia de la Salud (PAS) en los ingresos hospitalarios por accidente cerebrovascular (ACV) en el estado de Pernambuco, Brasil. Esta evaluación del impacto de la política utilizó un enfoque cuasi-experimental que consiste en un estimador de diferencias en diferencias, ponderado por el emparejamiento de puntuación de propensión para hacer frente a posibles factores de confusión. El estudio incluyó datos socioeconómicos, demográficos y epidemiológicos de bases de datos oficiales brasileñas de 2010 a 2019. El grupo de tratamiento se compuso de los 134 municipios que implementaron el PAS a partir de 2011 y los 51 municipios que no lo hicieron se asignaron al grupo de comparación. Se utilizó el algoritmo del vecino más próximo (N5) para emparejar los municipios tratados y los del grupo de comparación y crear las ponderaciones que se emplearon para evaluar el efecto medio del tratamiento sobre los tratados (ATT) en el estimador de diferencias en diferencias. Hubo 2.771 hospitalizaciones por ACV en 2010 (0,51% de todas las hospitalizaciones) y 11.542 (2%) en 2019. Los municipios que aplicaron el PAS tuvieron un 18,37% menos de hospitalizaciones en comparación con sus homólogos del grupo de comparación. El impacto del programa en la reducción de las tasas de hospitalización fue gradualmente mayor entre los hombres (ATT: -0,1932) y entre las personas de 71 a 80 años (ATT: -0,1911). Todos los resultados fueron estadísticamente significativos al nivel del 5%. El PAS redujo la hospitalización por ACV en varios grupos de población, pero principalmente en aquellos en los que la prevalencia subyacente de ACV es mayor, lo que refuerza la importancia de las inversiones públicas en políticas de promoción de la salud diseñadas para impulsar cambios en los estilos de vida.
Evaluación de Programas y Proyectos de Salud;
Enfermedad Crónica; Promoción de la Salud;
Puntaje de Propensión; Accidente CerebrovascularPernambuco State Foundation for the Support of Science and Technology (FACEPE), and the Brazilian National Research Council (CNPq)
Validación del Nursing Activities Score en unidades de cuidados intensivos portuguesas
Objective: to describe the process of adaptation and validation of the Nursing Activities Score to the Portuguese context. Method:
this was a pilot study of adaptation and validation of the Nursing Activities Score with a sample consisting of 67 patients hospitalized
in the intensive care units of three Portuguese hospitals. The construct validity was assessed through factor analysis procedures and
the internal consistency of the items was measured through the Cronbach’s alpha coeffi cient. Results: a mean workload value of
63.04% (SD = 14.25; Median = 61.30) was obtained. Psychometric data revealed a Cronbach’s alpha of 0.71 in the total scale,
indicating an acceptable accuracy. Confi rmatory factor analysis suggested an appropriate adjustment between the model and the
data (χ2 (199) = 214.5, p = 0.214; CFI = 0.95; RMSA = 0.035). Conclusion: in the present study, the Portuguese version of the Nursing
Activities Score was found to be a valid instrument, enabling a safe assessment of the workload of nurses.Objetivo: descrever o processo de adaptação e validação do Nursing Activities Score para o contexto português. Método: trata-se
de um estudo-piloto de adaptação e validação do Nursing Activities Score, com amostra de 67 doentes internados em unidades de
cuidados intensivos de três hospitais portugueses. A validade de constructo avaliou-se mediante procedimentos de análise fatorial e a
consistência interna dos itens através do coefi ciente Alpha de Cronbach. Resultados: obteve-se um valor médio da carga de trabalho
de 63,04% (DP = 14,25; Mediana = 61,30). Os dados psicométricos revelaram um Alpha de Cronbach de 0,71, na escala total,
indicando uma fi delidade aceitável. A análise fatorial confi rmatória sugeriu um ajustamento adequado entre o modelo e os dados
(χ2(199) = 214,5, p = 0,214; CFI = 0,95; RMSA = 0,035). Conclusão: neste estudo, a versão portuguesa do Nursing Activities Score
revelou-se um instrumento válido, permitindo avaliar a carga de trabalho dos enfermeiros com segurançaObjetivo: describir el proceso de adaptación y validación del Nursing Activities Score al contexto portugués. Método: estudio
piloto de adaptación y validación del Nursing Activities Score, con muestra de 67 pacientes internados en unidades de cuidados
intensivos de tres hospitales portugueses. La validez del constructo se evaluó mediante análisis factorial y por consistencia
interna de los ítems evaluados a través del coefi ciente Alpha de Cronbach. Resultados: se obtuvo un valor medio de carga
de trabajo de 63,04% (SD=14,25; Mediana=61,30). Los datos psicométricos expresaron un Alpha de Cronbach de 0,71 en
la escala total, indicando fi delidad aceptable. El análisis factorial confi rmatorio sugirió un ajuste adecuado entre el modelo y os datos (χ2 (199)=214,5; p=0,214; CFI=0,95; RMSA=0,035). Conclusión: en este estudio, la versión portuguesa del Nursing Activities Score demostró ser un instrumento válido, permitiendo evaluar la carga de trabajo de los enfermeros con precisión
Assessment of angiogenesis by CD105 antigen in epithelial salivary gland neoplasms with diverse metastatic behavior
<p>Abstract</p> <p>Background</p> <p>Information on the biology of metastasis development in salivary gland tumors is scarce. Since angiogenesis seems associated with this phenomenon in other tumors, we sought to compare salivary gland tumors with diverse metastatic behavior in order to improve the knowledge and management of these lesions.</p> <p>Methods</p> <p>Samples from the most important salivary gland tumors were segregated according to its metastatic behavior and submitted to routine immunohistochemistry to identify vessels positive for CD105 expression. Frequency of positive cases and intratumoral microvessel density (IMD) was compared among the group of lesions.</p> <p>Results</p> <p>CD105 positive vessels were absent in normal salivary gland tissue, were rare in pleomorphic adenomas and adenoid cystic carcinomas (ACC), more common in polymorphous low-grade adenocarcinomas and highest in mucoepidermoid carcinomas. Only ACC with such feature were metastatic. IMD was higher in malignant rather than benign tumors.</p> <p>Conclusion</p> <p>Immunostaining of CD105 in salivary gland tumors implies participation of angiogenesis in the development of malignant lesions, as well as some role for myoepithelial cells in the control of new vessel formation. In addition, suggest that ACC with positive CD105 vessels are at higher risk for metastasis.</p
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