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1.
Braz J Biol ; 83: e276493, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38422255

RESUMO

This review article explores the potential of fermentations in the Amazon region as catalysts for economic and social development. It highlights the rich cultural and gastronomic diversity of the Amazon, focusing on indigenous fermented products. Two main products, tucupi and caxiri, are discussed in detail, emphasizing their significance in local cuisine and culture. The review examines the challenges and opportunities for industrial applications of these products, as well as their potential for social technology initiatives, particularly in the context of family farming. The sustainable production of native fermented products in the Amazon is seen as a means to preserve biodiversity, empower local communities, and promote cultural heritage. The article concludes that both industrial and social technologies have complementary roles in promoting economic growth, cultural preservation, and the well-being of the Amazon region, making it a promising hub for innovative and sustainable fermented food products on a global scale.


Assuntos
Biodiversidade , Tecnologia , Fermentação , Agricultura
2.
Sci Rep ; 13(1): 17258, 2023 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-37828024

RESUMO

X-ray spectroscopy is a demanded tool across multiple user communities. Here we report on a new station for X-ray emission spectroscopy at the Extreme Light Infrastructure Beamlines Facility. The instrument utilizes the von Hamos geometry and works with a number of different sample types, notably including liquid systems. We demonstrate a simple and reliable method for source position control using two cameras. This approach addresses energy calibration dependence on sample position, which is a characteristic source of measurement uncertainty for wavelength dispersive spectrometers in XES arrangement. We also present a straightforward procedure for energy calibration of liquid and powder samples to a thin film reference. The developed instrumentation enabled us to perform the first experimental determination of the Kα lines of liquidized K3Fe(CN)6 as well as powdered and liquidized FeNH4(SO4)2. Finally, we report on proof-of-principle use of a colliding jet liquid sample delivery system in an XES experiment.

3.
Rev. neurol. (Ed. impr.) ; 76(S01)Ene-Jun. 2023. tab
Artigo em Espanhol | IBECS | ID: ibc-219308

RESUMO

Introducción: La esclerosis múltiple es una enfermedad neurológica crónica con numerosos tratamientos modificadores de la enfermedad disponibles, incluido el dimetilfumarato (DMF), una terapia de primera línea para la esclerosis múltiple remitente-recurrente. Aunque las tasas de discontinuación del DMF suelen ser bajas en los ensayos clínicos, la falta de adhesión al tratamiento se asocia con peores resultados clínicos. Evaluar la adhesión en el mundo real y los factores predictivos es fundamental para mejorar los resultados clínicos de los pacientes. Este estudio evaluó la adhesión al DMF durante 24 meses en una cohorte de pacientes tratados en un centro portugués. Pacientes y métodos: Estudio prospectivo no intervencionista, de un solo centro, con un seguimiento de 24 meses. El estudio incluyó a pacientes adultos con esclerosis múltiple remitente-recurrente tratados con DMF en la práctica clínica habitual. Se calculó la adhesión al DMF y se consideró que los pacientes eran adherentes si el valor estaba por encima del 80%. Se compararon variables clínicas y sociodemográficas entre grupos. Resultados: De los 80 pacientes incluidos, el 74% eran mujeres, con una edad media de 39 años y una edad media en el momento del diagnóstico de 32 años. Veintiséis pacientes no habían recibido tratamiento previo. La adhesión varió entre el 93, el 82 y el 87,5% a los 6, 12 y 24 meses, respectivamente. No se encontraron diferencias entre los pacientes que no habían recibido tratamiento previo y los que sí lo habían recibido. Conclusión: Este análisis en el mundo real mostró una adhesión significativa al tratamiento con DMF durante dos años por parte de los pacientes portugueses. No obstante, estos resultados deben interpretarse considerando los cambios sustanciales en las consultas externas y las diversas restricciones periódicas debidas a la pandemia de COVID-19, que afectaron en gran medida al seguimiento de los pacientes y a la recopilación de datos.(AU)


Introduction: Multiple sclerosis is a chronic neurological disease with numerous disease-modifying treatments available, including dimethyl fumarate (DMF), a first-line therapy for relapsing-remitting multiple sclerosis. Although rates of discontinuation of DMF are generally low in clinical trials, non-adherence to treatment is associated with poorer clinical outcomes. Assessing real-world adherence and predictive factors is critical to be able to improve clinical outcomes for patients. This study evaluated adherence to DMF over 24 months in a cohort of patients treated in a Portuguese healthcare centre. Patients and methods: A prospective, non-interventional, single-centre study with 24 months’ follow-up was conducted. The study included adult patients with relapsing-remitting multiple sclerosis treated with DMF in routine clinical practice. Adherence to DMF was calculated and patients were considered to have adhered if the value was above 80%. Clinical and socio-demographic variables were compared between groups. Results: Of the 80 patients included, 74% were women, with a mean age of 39 years and a mean age of 32 years at diagnosis. Twenty-six patients had not received any previous treatment. Adherence varied between 93, 82 and 87.5% at 6, 12 and 24 months, respectively. No differences were found between patients who had not received any prior treatment and those who had been treated. Conclusion: This real-world analysis showed significant adherence to DMF treatment by Portuguese patients over a period of two years. However, these results must be interpreted in the light of the substantial changes in outpatient consultations and the various periodic restrictions due to the COVID-19 pandemic, which had an important effect on patient follow-up and data collection.(AU)


Assuntos
Humanos , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Esclerose Múltipla Recidivante-Remitente , Fumarato de Dimetilo , Doenças do Sistema Nervoso , Estudos Prospectivos , Neurologia , Portugal
4.
Rev Neurol ; 76(s01): S1-S6, 2023 01 31.
Artigo em Espanhol | MEDLINE | ID: mdl-36683265

RESUMO

INTRODUCTION: Multiple sclerosis is a chronic neurological disease with numerous disease-modifying treatments available, including dimethyl fumarate (DMF), a first-line therapy for relapsing-remitting multiple sclerosis. Although rates of discontinuation of DMF are generally low in clinical trials, non-adherence to treatment is associated with poorer clinical outcomes. Assessing real-world adherence and predictive factors is critical to be able to improve clinical outcomes for patients. This study evaluated adherence to DMF over 24 months in a cohort of patients treated in a Portuguese healthcare centre. PATIENTS AND METHODS: A prospective, non-interventional, single-centre study with 24 months' follow-up was conducted. The study included adult patients with relapsing-remitting multiple sclerosis treated with DMF in routine clinical practice. Adherence to DMF was calculated and patients were considered to have adhered if the value was above 80%. Clinical and socio-demographic variables were compared between groups. RESULTS: Of the 80 patients included, 74% were women, with a mean age of 39 years and a mean age of 32 years at diagnosis. Twenty-six patients had not received any previous treatment. Adherence varied between 93, 82 and 87.5% at 6, 12 and 24 months, respectively. No differences were found between patients who had not received any prior treatment and those who had been treated. CONCLUSION: This real-world analysis showed significant adherence to DMF treatment by Portuguese patients over a period of two years. However, these results must be interpreted in the light of the substantial changes in outpatient consultations and the various periodic restrictions due to the COVID-19 pandemic, which had an important effect on patient follow-up and data collection.


TITLE: Adhesión real al dimetilfumarato en pacientes con esclerosis múltiple remitente-recurrente.Introducción. La esclerosis múltiple es una enfermedad neurológica crónica con numerosos tratamientos modificadores de la enfermedad disponibles, incluido el dimetilfumarato (DMF), una terapia de primera línea para la esclerosis múltiple remitente-recurrente. Aunque las tasas de discontinuación del DMF suelen ser bajas en los ensayos clínicos, la falta de adhesión al tratamiento se asocia con peores resultados clínicos. Evaluar la adhesión en el mundo real y los factores predictivos es fundamental para mejorar los resultados clínicos de los pacientes. Este estudio evaluó la adhesión al DMF durante 24 meses en una cohorte de pacientes tratados en un centro portugués. Pacientes y métodos. Estudio prospectivo no intervencionista, de un solo centro, con un seguimiento de 24 meses. El estudio incluyó a pacientes adultos con esclerosis múltiple remitente-recurrente tratados con DMF en la práctica clínica habitual. Se calculó la adhesión al DMF y se consideró que los pacientes eran adherentes si el valor estaba por encima del 80%. Se compararon variables clínicas y sociodemográficas entre grupos. Resultados. De los 80 pacientes incluidos, el 74% eran mujeres, con una edad media de 39 años y una edad media en el momento del diagnóstico de 32 años. Veintiséis pacientes no habían recibido tratamiento previo. La adhesión varió entre el 93, el 82 y el 87,5% a los 6, 12 y 24 meses, respectivamente. No se encontraron diferencias entre los pacientes que no habían recibido tratamiento previo y los que sí lo habían recibido. Conclusión. Este análisis en el mundo real mostró una adhesión significativa al tratamiento con DMF durante dos años por parte de los pacientes portugueses. No obstante, estos resultados deben interpretarse considerando los cambios sustanciales en las consultas externas y las diversas restricciones periódicas debidas a la pandemia de COVID-19, que afectaron en gran medida al seguimiento de los pacientes y a la recopilación de datos.


Assuntos
COVID-19 , Esclerose Múltipla Recidivante-Remitente , Esclerose Múltipla , Adulto , Humanos , Feminino , Masculino , Fumarato de Dimetilo/uso terapêutico , Fumarato de Dimetilo/efeitos adversos , Esclerose Múltipla Recidivante-Remitente/tratamento farmacológico , Imunossupressores/uso terapêutico , Imunossupressores/efeitos adversos , Esclerose Múltipla/tratamento farmacológico , Pandemias , Estudos Prospectivos
5.
J Environ Manage ; 328: 116910, 2023 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-36495826

RESUMO

Urban air pollution is a global concern impairing citizens' health, thus monitoring is a pressing need for city managers. City-wide networks for air pollution monitoring based on low-cost sensors are promising to provide real-time data with detail and scale never before possible. However, they still present limitations preventing their ubiquitous use. Thus, this study aimed to perform a post-deployment validation and calibration based on two step methods for ozone low-cost sensor of a city-wide network for air pollution and meteorology monitoring using low-cost sensors focusing on the main challenges. Four of the 23 data collection units (DCUs) of the UrbanSense network installed in Porto city (Portugal) with low-cost sensors for particulate matter (PM), carbon monoxide (CO), ozone (O3), and meteorological variables (temperature, relative humidity, luminosity, precipitation, and wind speed and direction) were evaluated. This study identified post-deployment challenges related to their validation and calibration. The preliminary validation showed that PM, CO and precipitation sensors recorded only unreliable data, and other sensors (wind speed and direction) very few data. A multi-step calibration strategy was implemented: inter-DCU calibration (1st step, for O3, temperature and relative humidity) and calibration with a reference-grade instrument (2nd step, for O3). In the 1st step, multivariate linear regression (MLR) resulted in models with better performance than non-linear models such as artificial neural networks (errors almost zero and R2 > 0.80). In the 2nd step, the calibration models using non-linear machine learning boosting algorithms, namely Stochastic Gradient Boosting Regressor (both with the default and post-tuning hyper-parameters), performed better than artificial neural networks and linear regression approaches. The calibrated O3 data resulted in a marginal improvement from the raw data, with error values close to zero, with low predictability (R2 ∼ 0.32). The lessons learned with the present study evidenced the need to redesign the calibration strategy. Thus, a novel multi-step calibration strategy is proposed, based on two steps (pre and post-deployment calibration). When performed cyclically and continuously, this strategy reduces the need for reference instruments, while probably minimising data drifts over time. More experimental campaigns are needed to collect more data and further improve calibration models.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Ozônio , Poluentes Atmosféricos/análise , Calibragem , Monitoramento Ambiental/métodos , Poluição do Ar/análise , Material Particulado/análise , Coleta de Dados
6.
Sci Rep ; 12(1): 17330, 2022 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-36243774

RESUMO

Tough and impact-resistant ceramic systems offer a wide range of remarkable opportunities beyond those offered by the conventional brittle ceramics. However, despite their promise, the availability of traditional manufacturing technique for fabricating such advanced ceramic structures in a highly controllable and scalable manner poses a significant manufacturing bottleneck. In this study, a precise and programmable laser manufacturing system was used to manufacture topologically interlocking ceramics. This manufacturing strategy offers feasible mechanisms for a precise material architecture and quantitative process control, particularly when scalability is considered. An optimized material removal method that approaches near-net shaping was employed to fabricate topologically interlocking ceramic systems (load-carrying assemblies of building blocks interacting by contact and friction) with different architectures (i.e., interlocking angles and building block sizes) subjected to low-velocity impact conditions. These impacts were evaluated using 3D digital image correlation. The optimal interlocked ceramics exhibited a higher deformation (up to 310%) than the other interlocked ones advantageous for flexible protections. Their performance was tuned by controlling the interlocking angle and block size, adjusting the frictional sliding, and minimizing damage to the building blocks. In addition, the developed subtractive manufacturing technique leads to the fabrication of tough, impact-resistant, damage-tolerant ceramic systems with excellent versatility and scalability.

7.
Neurol Sci ; 42(5): 1995-2003, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-32997282

RESUMO

BACKGROUND: Fingolimod, an oral sphingosine 1-phosphate receptor modulator, is approved by EMA for relapsing-remitting multiple sclerosis (RRMS). OBJECTIVES: To assess the effectiveness and safety of fingolimod in patients with RRMS in real-world clinical practice in Portugal. METHODS: Retrospective, multicentre, non-interventional study, reporting 3 years follow-up of data collected from October 2015 to July 2016. Sociodemographic data and previous treatments at baseline and data regarding disease evolution, including number of relapses, annualised relapse rates (ARR) and Expanded Disability Status Scale (EDSS), were collected. RESULTS: Two-hundred and seventy-five participants were enrolled in the REALMS study. Results showed that the main reason to switch to fingolimod was failure of previous treatment (56.7%) and only 3.6% were naïve patients. In the total population, there was a significant decrease in ARR of 64.6% in the first year of treatment, 79.7% in the second year and 82.3% in the third year, compared with baseline. More than 67.0% of patients had no relapses during the 3 years after switching to fingolimod. EDSS remained stable throughout the study. CONCLUSIONS: Therapy with fingolimod showed a sustained effectiveness and safety over the 3 years, particularly on patients switched from first-line drugs (BRACE). No new safety issues were reported.


Assuntos
Esclerose Múltipla Recidivante-Remitente , Esclerose Múltipla , Cloridrato de Fingolimode/efeitos adversos , Humanos , Imunossupressores/efeitos adversos , Esclerose Múltipla Recidivante-Remitente/tratamento farmacológico , Portugal/epidemiologia , Estudos Retrospectivos , Resultado do Tratamento
9.
Nanotechnology ; 32(4): 042003, 2021 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-33155576

RESUMO

This roadmap on Nanotechnology for Catalysis and Solar Energy Conversion focuses on the application of nanotechnology in addressing the current challenges of energy conversion: 'high efficiency, stability, safety, and the potential for low-cost/scalable manufacturing' to quote from the contributed article by Nathan Lewis. This roadmap focuses on solar-to-fuel conversion, solar water splitting, solar photovoltaics and bio-catalysis. It includes dye-sensitized solar cells (DSSCs), perovskite solar cells, and organic photovoltaics. Smart engineering of colloidal quantum materials and nanostructured electrodes will improve solar-to-fuel conversion efficiency, as described in the articles by Waiskopf and Banin and Meyer. Semiconductor nanoparticles will also improve solar energy conversion efficiency, as discussed by Boschloo et al in their article on DSSCs. Perovskite solar cells have advanced rapidly in recent years, including new ideas on 2D and 3D hybrid halide perovskites, as described by Spanopoulos et al 'Next generation' solar cells using multiple exciton generation (MEG) from hot carriers, described in the article by Nozik and Beard, could lead to remarkable improvement in photovoltaic efficiency by using quantization effects in semiconductor nanostructures (quantum dots, wires or wells). These challenges will not be met without simultaneous improvement in nanoscale characterization methods. Terahertz spectroscopy, discussed in the article by Milot et al is one example of a method that is overcoming the difficulties associated with nanoscale materials characterization by avoiding electrical contacts to nanoparticles, allowing characterization during device operation, and enabling characterization of a single nanoparticle. Besides experimental advances, computational science is also meeting the challenges of nanomaterials synthesis. The article by Kohlstedt and Schatz discusses the computational frameworks being used to predict structure-property relationships in materials and devices, including machine learning methods, with an emphasis on organic photovoltaics. The contribution by Megarity and Armstrong presents the 'electrochemical leaf' for improvements in electrochemistry and beyond. In addition, biohybrid approaches can take advantage of efficient and specific enzyme catalysts. These articles present the nanoscience and technology at the forefront of renewable energy development that will have significant benefits to society.

10.
Sci Adv ; 6(14): eaaz0421, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32284978

RESUMO

Blue natural pigments are rare, especially among plants. However, flowering species that evolved to attract Hymenoptera pollinators are colored by blue anthocyanin-metal complexes. Plants lacking anthocyanins are pigmented by betalains but are unable to produce blue hues. By extending the π-system of betalains, we designed a photostable and metal-free blue dye named BeetBlue that did not show toxicity to human hepatic and retinal pigment epithelial cells and does not affect zebrafish embryonal development. This chiral dye can be conveniently synthesized from betalamic acid obtained from hydrolyzed red beetroot juice or by enzymatic oxidation of l-dopa. BeetBlue is blue in the solid form and in solution of acidified polar molecular solvents, including water. Its capacity to dye natural matrices makes BeetBlue the prototype of a new class of low-cost bioinspired chromophores suitable for a myriad of applications requiring a blue hue.


Assuntos
Corantes/química , Corantes/isolamento & purificação , Pigmentos Biológicos/química , Plantas/química , Animais , Fenômenos Químicos , Cor , Corantes/análise , Corantes/toxicidade , Teoria da Densidade Funcional , Metais , Estrutura Molecular , Pigmentação , Análise Espectral , Peixe-Zebra
11.
Eval Program Plann ; 80: 101801, 2020 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-32097816

RESUMO

The Hospital Pharmacy of a Local Health Unit (LHU) in greater Oporto plays a major role in the community. In addition to providing medicines to the entire Internal Unit, it has created a service called "Hospital Ambulatory Pharmacy", which allows continued hospital treatments at home, in a more comfortable and familiar environment. This is mostly due uderfunding which has hindered recruitment of health professionals as well a growing concern for the comfort of patients as they convalesce. The Hospital Ambulatory Pharmacy's main problems are both recurring stock-outs and over-stocks; the fact that medicines's delivery routes are not completed, and that medical staff lacks awareness of the techniques to overcome the logistic issues involved. As a methodology, a context analysis was carried out, KPI's were created to quantify the problems and raise health professionals' awareness of what was happening. Solutions for storage were analysed and visits were made to a central hospital to analyse the solutions adopted to solve the same problems. The most appropriate inventory management policies were considered for the organization of existing and further resources. We chose to create an Advanced Warehouse with Level Replenishment. The levels were defined considering the demand of each medicine and divided into three different classes to use the best strategy for each type of demand. Then, and with the help of the LHU IT team, the inventory management module of the information system was parameterized, so stock replenishment could be done electronically. All these changes resulted in a 30 % reduction in stock-out. At the beginning of the study, stock-outs would reach peaks of 6 %. These were reduced to 4.5 % at a point at which professionals were already more aware of the logistic problem, and finally to 1.5 %, in the final phase, at a time when the proposal had already been implemented. Over-stock was reduced by 66 %. Delivery routes were stipulated, and compliance was verified. A novel service developed to increase the well-being of patients monitored at home which it is intended to improve the service provided to the users and at the same time reduce operational costs. As a contribution to the knowledge, in addition to the case study presented to be a novelty in terms of scientific articles published because it is a service implemented in the distribution of medications to patients at home, mostly with oncologic diseases. Several methods from Lean Thinking were used, such as, Kanban System and Advanced Warehouse for inventory management levelling and optimization techniques, as well as, operational KPIs, with the purpose to reach out the improvement of program planning and evaluation. This approach resulted in some improvements, namely, the increase of the quality of the healthcare services for the population. And, in terms to reduce stock and excess stock-outs, to reduce inventory costs, setting the delivery routes, raising the entire medical team's awareness of the problem and committing to optimization a reality.

12.
Toxicol In Vitro ; 65: 104771, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31935486

RESUMO

Schistosomiasis is one of the most significant neglected tropical diseases, affecting around 260 million people worldwide, and Praziquantel is currently the only available drug for the treatment of infected persons. Thus, the search for new schistosomicidal compounds is urgent. The objective of this study was to investigate of the schistosomicidal effect of barbatic acid, a lichen metabolite, on adult worms of Schistosoma mansoni. The in vitro schistosomicidal effect was evaluated through the assessment of motility and mortality, cellular viability of the worms and ultrastructural analysis through scanning electron microscopy. To evaluate the cytotoxicity of barbatic acid, a cell viability assay was performed with human peripheral blood mononuclear cells. Barbatic acid showed a schistosomicidal effect after 3 h of exposure. At the end of 24 h the concentrations of 50-200 µM presented lethality on the worms. Motility changes were observed at sublethal concentrations. The IC50 obtained by the cell viability assay for S. mansoni was 99.43 µM. Extensive damage to the worm's tegument was observed from 25 µM. No cytotoxicity was observed on human peripheral blood mononuclear cells. This report provides data showing the schistosomicidal effect of barbatic acid on S. mansoni, causing death, motility changes and ultrastructural damage to worms. In addition, barbatic acid was shown to be non-toxic to human peripheral blood mononuclear cells at concentrations that are effective against S. mansoni.


Assuntos
Ascomicetos/química , Ácidos Ftálicos/toxicidade , Schistosoma mansoni/efeitos dos fármacos , Animais , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Humanos , Leucócitos Mononucleares/efeitos dos fármacos , Líquens/química , Microscopia Eletrônica de Varredura , Schistosoma mansoni/ultraestrutura
13.
Sci. Adv. ; 6(14): eaaz0421, 2020.
Artigo em Inglês | Sec. Est. Saúde SP, SESSP-IBPROD, Sec. Est. Saúde SP | ID: but-ib17609

RESUMO

Blue natural pigments are rare, especially among plants. However, flowering species that evolved to attract Hymenoptera pollinators are colored by blue anthocyanin-metal complexes. Plants lacking anthocyanins are pigmented by betalains but are unable to produce blue hues. By extending the p-system of betalains, we designed a photostable and metal-free blue dye named BeetBlue that did not show toxicity to human hepatic and retinal pigment epithelial cells and does not affect zebrafish embryonal development. This chiral dye can be conveniently synthesized from betalamic acid obtained from hydrolyzed red beetroot juice or by enzymatic oxidation of L-dopa. BeetBlue is blue in the solid form and in solution of acidified polar molecular solvents, including water. Its capacity to dye natural matrices makes BeetBlue the prototype of a new class of low-cost bioinspired chromophores suitable for a myriad of applications requiring a blue hue.

14.
Sci Adv, v. 6, n. 14, eaaz0421, abr. 2020
Artigo em Inglês | Sec. Est. Saúde SP, SESSP-IBPROD, Sec. Est. Saúde SP | ID: bud-3010

RESUMO

Blue natural pigments are rare, especially among plants. However, flowering species that evolved to attract Hymenoptera pollinators are colored by blue anthocyanin-metal complexes. Plants lacking anthocyanins are pigmented by betalains but are unable to produce blue hues. By extending the p-system of betalains, we designed a photostable and metal-free blue dye named BeetBlue that did not show toxicity to human hepatic and retinal pigment epithelial cells and does not affect zebrafish embryonal development. This chiral dye can be conveniently synthesized from betalamic acid obtained from hydrolyzed red beetroot juice or by enzymatic oxidation of L-dopa. BeetBlue is blue in the solid form and in solution of acidified polar molecular solvents, including water. Its capacity to dye natural matrices makes BeetBlue the prototype of a new class of low-cost bioinspired chromophores suitable for a myriad of applications requiring a blue hue.

15.
Struct Dyn ; 6(2): 024901, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31041363

RESUMO

"Probe-before-destroy" methodology permitted diffraction and imaging measurements of intact specimens using ultrabright but highly destructive X-ray free-electron laser (XFEL) pulses. The methodology takes advantage of XFEL pulses ultrashort duration to outrun the destructive nature of the X-rays. Atomic movement, generally on the order of >50 fs, regulates the maximum pulse duration for intact specimen measurements. In this contribution, we report the electronic structure damage of a molecule with ultrashort X-ray pulses under preservation of the atoms' positions. A detailed investigation of the X-ray induced processes revealed that X-ray absorption events in the solvent produce a significant number of solvated electrons within attosecond and femtosecond timescales that are capable of coulombic interactions with the probed molecules. The presented findings show a strong influence on the experimental spectra coming from ionization of the probed atoms' surroundings leading to electronic structure modification much faster than direct absorption of photons. This work calls for consideration of this phenomenon in cases focused on samples embedded in, e.g., solutions or in matrices, which in fact concerns most of the experimental studies.

16.
Data Brief ; 19: 1393-1397, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30225292

RESUMO

In this study, the molluscicidal and antiparasitic activities of divaricatic acid was evaluated, targeting the mollusc Biomphalaria glabrata and cercariae of the helminth Schistosoma mansoni. Divaricatic acid showed high toxicity against both adult snails (5.5 µg/mL) and embryos (20 µg/mL after 6 h of exposure). Similar activity was observed in S. mansoni cercariae after only a short exposure time. The divaricatic acid proved to be a promising substance for the control of the snail B. glabrata, an intermediate host of schistosomiasis, as well as the cercariae of the pathogen.

17.
Int J Radiat Biol ; 94(9): 838-843, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29939813

RESUMO

PURPOSE: Some phytochemicals have shown the potential of being radiomodifiers, especially phenolic compounds, such as lichenic secondary metabolites. To evaluate the phytochemical usnic acid as a radiomodifier, embryonic cells of molluscs have been used due to their ease of collection, high sensitivity to physical and chemical agents, well-known embryology and low cost for analysis. MATERIALS AND METHODS: This study aimed to assess the radiosensitizing action of usnic acid on Biomphalaria glabrata embryos. Samples were irradiated with 4 Gy of gamma rays from a 60Co source (dose rate 2.906 Gy/h). An acute toxicity test was performed using B. glabrata embryos in the blastula stage, in order to determine the toxicity of usnic acid and to establish the lethal Concentration for 50% (LC50). Subsequently, the radiomodifing capacity of usnic acid was estimated using assays with B. glabrata embryos. RESULTS: Irradiation increased the number of non-viable embryos compared to unirradiated controls. Additionally, it was observed that embryos exposed to a non-toxic concentration of usnic acid (0.6 µg/mL) before irradiation showed a further enhancement in non-viable embryos when compared with exposure to ionizing radiation alone. CONCLUSION: The results presented here indicate that usnic acid makes cells more sensitive to the damaging effects of radiation.


Assuntos
Benzofuranos/farmacologia , Biomphalaria/embriologia , Embrião não Mamífero/efeitos dos fármacos , Embrião não Mamífero/efeitos da radiação , Radiossensibilizantes/farmacologia , Animais , Benzofuranos/toxicidade , Radioisótopos de Cobalto , Raios gama , Dose Letal Mediana , Radiossensibilizantes/toxicidade
18.
Acta Trop ; 178: 97-102, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29097241

RESUMO

In this study, the molluscicidal and antiparasitic activities of divaricatic acid was evaluated, targeting the mollusc Biomphalaria glabrata and cercariae of the helminth Schistosoma mansoni. In addition, the environmental toxicity of divaricatic acid was assessed by bioassay using the microcrustacean Artemia salina. Divaricatic acid showed high toxicity against both adult snails (5µg/mL) and embryos (20µg/mL after 6h of exposure). Similar activity was observed in Schistosoma mansoni cercariae after only a short exposure time (10µg/mL after 30min of exposure). The divaricatic acid did not show toxicity in the acute test using Artemia salina at concentrations equal to or below 200µg/mL. The divaricatic acid proved to be a promising substance for the elimination of the snail Biomphalaria glabrata, an intermediate host of schistosomiasis, as well as the cercariae of the pathogen, while being non-toxic to the Artemia salina at the same concentrations. This is the first experimental observation of the molluscicidal and cercaricide activity of divaricatic acid.


Assuntos
Antiparasitários/farmacologia , Biomphalaria/efeitos dos fármacos , Depsídeos/farmacologia , Moluscocidas/farmacologia , Schistosoma mansoni/efeitos dos fármacos , Animais , Artemia , Cercárias/efeitos dos fármacos
19.
Anal Chim Acta ; 984: 134-139, 2017 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-28843556

RESUMO

We present a proof-of-principle approach for discriminating chiral enantiomers based on the phenomenon of multiphoton photoelectron circular dichroism. A novel stereo detection setup was used to measure the number of photoelectrons emitted from chiral molecules in directions parallel or anti-parallel to the propagation of the ionising femtosecond laser pulses. In this study, we show how these asymmetries in the ketones camphor and fenchone depend upon the ellipticity of the laser pulses and the enantiomeric excess of the sample. By using a high repetition rate femtosecond laser, enantiomer excesses with uncertainties at the few-percent level could be measured in close to real-time. As the instrument is compact, and commercial turnkey femtosecond lasers are readily available, the development of a stand-alone chiral analysis instrument for a range of applications is now possible.

20.
Rev Port Pneumol (2006) ; 23(2): 85-89, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28196610

RESUMO

INTRODUCTION: Lung cancer staging has recently evolved to include endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) for nodal assessment. AIM: Evaluate the performance and safety of EBUS-TBNA as a key component of a staging algorithm for non-small cell lung carcinoma (NSCLC) and as a single investigation technique for diagnosis and staging of NSCLC. METHODS: Patients undergoing EBUS-TBNA for NSCLC staging at our institution between April 1, 2010 and December 31, 2014 were consecutively included with prospective data collection. EBUS-TBNA was performed under general anesthesia through a rigid scope. RESULTS: A total of 122 patients, 84.4% males, mean age 64.2 years. Histological type: 78 (63.9%) adenocarcinoma, 33 (27.0%) squamous cell carcinoma, 11 (8.9%) undifferentiated/other NSCLC. A total of 435 lymph node stations were punctured. Median number of nodes per patient was 4. EBUS-TBNA nodal staging: 63 (51.6%) N0; 8 (6.5%) N1; 34 (27.9%) N2, and 17 (13.9%) N3. EBUS-TBNA was the primary diagnostic procedure in 27 (22.1%) patients. EBUS-TBNA NSCLC staging had a sensitivity, specificity, positive predictive value, negative predictive value, and diagnostic accuracy rate of 83.3, 100, 100, 86.1, and 91.8%, respectively. No complications were attributable to the procedure. CONCLUSION: A comprehensive lung cancer staging strategy that includes EBUS-TBNA seems to be safe and effective. Our EBUS-TBNA performance and safety in this particular setting was in line with previously published reports. Additionally, our study showed that, in selected patients, lung cancer diagnosis and staging are achievable with a single endoscopic technique.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/patologia , Neoplasias Pulmonares/patologia , Brônquios , Carcinoma Pulmonar de Células não Pequenas/secundário , Aspiração por Agulha Fina Guiada por Ultrassom Endoscópico/métodos , Feminino , Humanos , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias
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