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1.
Rev. biol. trop ; 72(1): e54500, ene.-dic. 2024. graf
Artigo em Espanhol | LILACS, SaludCR | ID: biblio-1559314

RESUMO

Resumen Introducción: La melina (Gmelina arborea), es una especie de gran interés por su madera y propiedades medicinales. En Costa Rica, existen clones genéticamente superiores que se propagan sin el conocimiento de la edad ontogénica y fisiológica de los materiales. Objetivo: Evaluar la relación del contenido de fenoles y ligninas en hojas, peciolos, tallos y raíces de plantas con diferentes edades. Métodos: Los contenidos de fenoles y ligninas totales se determinaron mediante el método colorimétrico de Folin-Ciocalteu y el método de extracción alcalina, respectivamente. Para la investigación se eligieron plantas in vitro "año cero" y árboles de año y medio, cuatro, siete y 20 años. El muestreo se realizó en marzo y abril del 2021. Resultados: Se demostró que todas las partes de la planta analizadas contienen compuestos fenólicos y ligninas, independientemente de su edad. No hubo una correlación positiva entre la edad con el contenido de fenoles y ligninas para ninguna condición de desarrollo, pues los valores más altos no se obtuvieron en los árboles más longevos. Los extractos de hojas de las plantas in vitro y los árboles de siete años mostraron, respectivamente, los contenidos más altos de fenoles y ligninas para todas las condiciones (P < 0.05). Los valores promedio más bajos de compuestos fenólicos para todas las condiciones se obtuvieron en los árboles de cuatro años. Respecto a las ligninas, el contenido más bajo se presentó en las raíces más longevas, aunque la tendencia no se mantuvo para el resto de las partes de la planta. Conclusiones: La investigación muestra los primeros resultados del contenido de compuestos fenólicos y ligninas presentes en diferentes tejidos de una especie forestal de edades diferentes. Por lo tanto, son los primeros valores de referencia acerca del compromiso bioquímico para la síntesis fenólica según la edad y el estado de desarrollo específico de una planta leñosa.


Abstract Introduction: Melina (Gmelina arborea) is a tree species of great interest for its wood and medicinal properties. In Costa Rica, there are genetically superior clones that are propagated without knowledge of the ontogenic and physiological age of the materials. Objective: To evaluate how age influences the content of phenols and lignins in leaves, petioles, stems, and roots of melina plants. Methods: The total phenolic and lignins contents were determined using Folin-Ciocalteu colorimetric method and alkaline extraction method, respectively. Plants of five different ages were chosen for the investigation (in vitro plants "year 0" and trees of a year and a half, four, seven and 20 years). Sampling was done in March and April 2021. Results: All parts of the plant analyzed contain phenolic compounds and lignins, regardless of their age. There was no positive correlation between age and phenol and lignin content for any development condition, since the highest values were not obtained in the oldest trees. Leaf extracts from in vitro plants and seven-year-old trees showed, respectively, the highest phenol and lignin contents for all conditions (P < 0.05). The lowest average values of phenolic compounds for all conditions were obtained in four-year-old trees. Regarding lignins, the lowest content occurred in the oldest roots, although the trend was not maintained for the rest of the plant parts. Conclusions: This study provides the first results of the content of phenolic compounds and lignins present in different tissues of a forest species of different ages. Therefore, they are the first reference values about the biochemical commitment for phenolic synthesis according to the age and the specific developmental stage of a woody plant.


Assuntos
Fenóis/análise , Árvores , Lignina/análise , Estudos de Amostragem , Lamiaceae , Compostos Fitoquímicos/análise
2.
Sci Rep ; 14(1): 1602, 2024 01 18.
Artigo em Inglês | MEDLINE | ID: mdl-38238355

RESUMO

Skin disorders affect millions of people all over the world. There are limited options to treat dermal illnesses such as vitiligo, psoriasis, and atopic dermatitis (eczema). Central American ferns are a potential source of bioactive metabolites against those diseases. Currently, Polypodium leucotomos Poir. is the only one being commercially utilized for this purpose. In this work, we evaluated the concentration of the skin bioactive compounds: quinic and chlorogenic acid, in the extract of 20 wild ferns from Costa Rica. We also evaluated the antimicrobial capabilities of the crude extracts of wild ferns and the sun protection factor (SPF) of the extracts. We found 19 out of 20 have either an important concentration of the compounds mentioned above or antimicrobial properties. Also, most samples result in higher SPF than P. aureum's rhizome. We also have studied the fern acclimatization, at different shading conditions, finding a significant influence of the culturing conditions on metabolite production. After acclimatization. So far, we demonstrate that various ferns included in this study are a potential source of treatments for skin conditions.


Assuntos
Gleiquênias , Polypodiaceae , Polypodium , Vitiligo , Humanos , Antibacterianos/farmacologia , Costa Rica , Extratos Vegetais/farmacologia
3.
Ecotoxicol Environ Saf ; 270: 115919, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38176183

RESUMO

Volcanic eruptions can have long-lasting negative effects on nearby environments and communities, especially those relying on agriculture. The Tungurahua and Sangay volcanoes in Ecuador's highlands pose a significant risk to the region's agricultural economy and inhabitants. The most recent eruption of the Tungurahua volcano spanned from September 1999 to March 2016. Volcanic ash is known to contain both non-essential and essential elements for plant growth, but excessive amounts of the latter can also be toxic and disrupt physiological processes. Additionally, the use of pesticides and fertilizers introduces additional elements to agricultural soils, which can potentially transfer to edible plants and raise health concerns for consumers. Despite this, little is known about the impact of the Tungurahua volcano's latest eruption on soil deposition of micronutrient and heavy metals and their potential transfer to the food chain. To address this knowledge gap, we conducted a study to explore the impact of the Tungurahua volcano's latest eruption on soil deposition of Cd, Cr, Ni, Pb, As, Fe, Cu, Mn, and Zn, as well as the physicochemical characteristics of cultivated and uncultivated soil samples and vegetables in the cantons most affected by volcanic ash. According to our findings, the physicochemical properties, micronutrient, and heavy metal concentrations of both cultivated and uncultivated soils differ and, in some cases, exceeded the maximum limits established, which could affect the health of the soil as well as of human beings through the trophic chain. This study provides valuable information for monitoring the chemical and physical properties of soil and vegetables in areas affected by the Tungurahua volcanic activity and agriculture, aiding in understanding their impact on the environment, agriculture, and potential health risks associated with locally grown crops in rural Ecuadorian communities.


Assuntos
Metais Pesados , Poluentes do Solo , Oligoelementos , Humanos , Equador , Monitoramento Ambiental , Metais Pesados/análise , Solo/química , Poluição Ambiental , Verduras , Poluentes do Solo/análise , Medição de Risco , China
4.
J Microbiol Immunol Infect ; 56(2): 324-336, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37610206

RESUMO

BACKGROUND: Salmonella enterica serovar Typhimurium (S. Typhimurium) has become an important intestinal pathogen worldwide and is responsible for lethal invasive infections in populations at risk. There is at present an unmet need for preventive vaccines. METHODS: IRTA GN-3728 genome was sequenced by Illumina and d-glutamate and d-glutamate/d-alanine knockout-auxotrophs were constructed. They were characterized using electron microscopy, growth/viability curves, reversion analysis, and motility/agglutination assays. Their potential as vaccine candidates were explored using two BALB/c mouse models for Salmonella infections: a systemic and an intestinal inflammation. Clinical signs/body weight and survival were monitored, mucosal lactoferrin and specific/cross-reactive IgA/IgG were quantified by enzyme-linked-immunosorbent assays and bacterial shedding/burden in fecal/tissues were evaluated. RESULTS: The d-glutamate auxotroph, IRTA ΔmurI, is highly attenuated, immunogenic and fully protective against systemic infection. The IRTA ΔmurI Δalr ΔdadX double auxotroph, constructed to reinforce vaccine safety, showed a higher level of attenuation and was 100% effective against systemic disease. In the intestinal model, it proved to be safe, yielding a low-degree of mucosal inflammation, short-term shedding and undetectable invasiveness in the long-term, while eliciting cross-reactive fecal IgA/serum IgG against clinically relevant multidrug-resistant (MDR) S. Typhimurium strains. It also conferred protection against homologous oral challenge, and protected mice from local and extra-intestinal dissemination caused by one MDR strain responsible for an international outbreak of highly severe human infections. Additionally, oral vaccination promoted extended survival after lethal heterologous infection. CONCLUSION: This study yielded a very safe S. Typhimurium vaccine candidate that could be further refined for mucosal application against disease in humans.


Assuntos
Ácido Glutâmico , Salmonella typhimurium , Humanos , Animais , Camundongos , Salmonella typhimurium/genética , Alanina , Inflamação , Imunoglobulina G
5.
Food Sci Nutr ; 11(6): 3320-3328, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37324859

RESUMO

Ber is an antioxidant-rich fruit from Asia and has recently been cultured in Central America. The antioxidant capacity and antimicrobial activity of Z. mauritiana cultured of bers from Guanacaste, Costa Rica, were evaluated. Two farm locations and two cultivars were evaluated. Total polyphenolic compounds (TPC), proanthocyanidin compounds (PAC), and ascorbic acid were spectrophotometrically quantified. Antioxidant activity has been analyzed using the DPPH method. Antimicrobial susceptibility was determined using the Kirby-Bauer disk diffusion method. Ber samples contained 11-44 mg GAE/g TPC. Green fruits and leaves had the highest concentrations. The ascorbic acid concentration in ber fruits was determined between 251 and 466 mg/100 g. Ber vitamin C content is higher than most common fruits. Proanthocyanidin compounds were determined between 1.8 and 9.9 mg 4-MCG/g, and the highest concentration was observed in the leaves. Our samples showed the antioxidant activity of 90-387 µmol TE/g, which was moderate activity. The nutritional quality of ber fruits was related to maturity conditions. The ber fruits, a crop from Asia previously adapted to live in Costa Rica, are rich in vitamin C and TPC, and the concentration of those metabolites was even higher than the concentration reported in bers grown in other countries. The TPC and PACs had an interestingly wide antimicrobial spectrum. Cultivars and farm locations have a significant effect on metabolite production.

6.
Int J Antimicrob Agents ; 62(1): 106836, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37150362

RESUMO

The need for alternative drugs to treat methicillin-resistant Staphylococcus aureus (MRSA) bacteraemia has led to a focus on ceftaroline, for which clinical data remain scarce. Herein, the efficacy of ceftaroline fosamil for the treatment of experimental MRSA bacteraemia was compared with that of approved therapies. Five MRSA strains were tested in an immunocompetent BALB/c bacteraemia model. Serum pharmacokinetics of ceftaroline fosamil were determined using HPLC/MS Q-TOF. Two hours after infection with the MRSA strains, mice were administered 50 mg/kg of ceftaroline fosamil every 6 h, for 24 h. This regimen yielded a T>MIC of 61.5% for an MIC of 1 mg/L and proved efficacious against all strains, including an hVISA strain with non-susceptibility to daptomycin, as indicated by the reduction (mean ± s.d.) in log10 CFU/mL in blood of 2.34 ± 0.33 and log10 CFU/g in kidney of 2.08 ± 0.22. Similarly, treatment with daptomycin yielded a log reduction of 2.30 ± 0.60 in blood and 2.14 ± 0.31 in kidney. The decrease in bacterial density was less accentuated after treatment with vancomycin, which yielded 1.84 ± 0.73 and 1.95 ± 0.32 log reductions in blood and kidney, respectively. The results of the study showed that the efficacy of ceftaroline fosamil against MRSA bacteraemia in mice is not inferior to that of vancomycin and daptomycin, and indicated the potential use of ceftaroline fosamil against difficult-to-treat S. aureus bacteraemia. Considering these promising data, clinical trials should be conducted to ascertain the efficacy of the drug for treating bloodstream infections in humans.


Assuntos
Bacteriemia , Daptomicina , Staphylococcus aureus Resistente à Meticilina , Infecções Estafilocócicas , Humanos , Animais , Camundongos , Vancomicina/uso terapêutico , Vancomicina/farmacocinética , Daptomicina/uso terapêutico , Daptomicina/farmacocinética , Antibacterianos/uso terapêutico , Antibacterianos/farmacocinética , Bacteriemia/tratamento farmacológico , Bacteriemia/microbiologia , Modelos Animais de Doenças , Infecções Estafilocócicas/tratamento farmacológico , Infecções Estafilocócicas/microbiologia , Staphylococcus aureus , Cefalosporinas/uso terapêutico , Cefalosporinas/farmacocinética , Testes de Sensibilidade Microbiana , Ceftarolina
7.
Molecules ; 28(6)2023 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-36985600

RESUMO

Secondary metabolites from Hibiscus sabdariffa have been used to prevent different diseases. Roselle Hibiscus is known for being rich in phenolic bioactive compounds. The extraction conditions are directly related to the chemical composition and then to the overall bioactivity of the extract. In this study, a Box-Behnken experimental design has been used to optimize the antioxidant activity, considering four variables: ethanol:water ratio, temperature, extraction time, and solvent:solid ratio. The experiment comprises 27 experiments and 3 repetitions at the central point. The results are described by surface response analysis and a second-degree polynomial equation. The model explains 87% of the variation in the response. The maximum antioxidant activity is yielded when 1% solids are extracted in 35.5% ethanol at 60 °C for 33 min. Finally, a nutritional functional supplement of 495 µmol Trolox Equivalent (TE) antioxidant capacity was prepared with the optimized extract.


Assuntos
Antioxidantes , Hibiscus , Antioxidantes/farmacologia , Antioxidantes/análise , Hibiscus/química , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Suplementos Nutricionais , Etanol/análise , Bebidas/análise
8.
Vaccines (Basel) ; 10(10)2022 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-36298487

RESUMO

Pseudomonas aeruginosa is an opportunistic nosocomial pathogen that causes serious infections in the respiratory tract of immunocompromised or critically ill patients, and it is also a significant source of bacteremia. Treatment of these infections can be complicated due to the emergence of multidrug-resistant P. aeruginosa strains worldwide. Hence, the development of prophylactic vaccines is a priority for at-risk patients. We have previously developed a vaccine candidate with a single auxotrophy for D-glutamate, PAO1 ΔmurI, which protects against sepsis and acute pneumonia caused by P. aeruginosa. Given the paramount importance of safety in the development of live attenuated vaccines, we have improved the safety of the vaccine candidate by reducing the probability of a reversion to virulence by the inclusion of an additional auxotrophy for D-alanine. Single and double auxotrophs behaved in a similar manner in relation to the attenuation level, immunogenicity and protective efficacy, but the double auxotroph has the advantage of being more stable and safer as a candidate vaccine against respiratory infections caused by P. aeruginosa.

9.
Vaccines (Basel) ; 10(6)2022 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-35746561

RESUMO

The development of a whole-cell vaccine from bacteria auxotrophic for D-amino acids present in the bacterial cell wall is considered a promising strategy for providing protection against bacterial infections. Here, we constructed a prototype vaccine, consisting of a glutamate racemase-deficient mutant, for preventing Klebsiella pneumoniae infections. The deletion mutant lacks the murI gene and requires exogenous addition of D-glutamate for growth. The results showed that the K. pneumoniae ΔmurI strain is attenuated and includes a favourable combination of antigens for inducing a robust immune response and conferring an adequate level of cross-protection against systemic infections caused by K. pneumoniae strains, including some hypervirulent serotypes with elevated production of capsule polysaccharide as well as multiresistant K. pneumoniae strains. The auxotroph also induced specific production of IL-17A and IFN-γ. The rapid elimination of the strain from the blood of mice without causing disease suggests a high level of safety for administration as a vaccine.

10.
Molecules ; 27(4)2022 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-35209137

RESUMO

Vector-borne diseases, such as those transmitted by Aedes aegypti, are a constant threat to inhabitants of tropical regions of the planet. Synthetic chemicals are commonly used as a strategy to control them; however, these products are known to persist in ecosystems and drive the appearance of resistance genes in arthropod vectors. Thus, the use of natural products has emerged as an environmentally friendly alternative in integrated vector control strategies. The present bioguided study investigated the larvicidal potential of Ipomoea cairica extracts, fractionated using thin-layer and open-column chromatography, because this species has been shown to exert larvicidal effects on the genus Aedes. The objective of this study was to evaluate the nonvolatile components in ethanolic extract of I. cairica stems as a potential natural larvicidal, and coumarins, such as 7-hydroxy-6-methoxychromen-2-one (scopoletin) and 7-hydroxychromen-2-one (umbelliferone), were identified as major compounds; however, they were not shown to be responsible for the larvicidal activity. Based on the results of the larvicidal action tests, these coumarins are not directly responsible for the larvicidal activity, but this activity might be attributed to a synergistic effect of all the compounds present in the most active secondary fraction, called F.DCM, which had an LC50 value of 30.608 mg/L. This type of study has yet not been conducted in the region; therefore, it is an important contribution to recognizing a natural and easy-to-cultivate source of vector control, such I. cairica.


Assuntos
Aedes/efeitos dos fármacos , Inseticidas/farmacologia , Ipomoea/química , Compostos Fitoquímicos/farmacologia , Extratos Vegetais/farmacologia , Animais , Fracionamento Químico , Cromatografia Líquida de Alta Pressão , Cromatografia em Camada Fina , Relação Dose-Resposta a Droga , Inseticidas/química , Inseticidas/isolamento & purificação , Larva/efeitos dos fármacos , Espectrometria de Massas , Compostos Fitoquímicos/química , Compostos Fitoquímicos/isolamento & purificação , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação
11.
Environ Res ; 197: 111068, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33785328

RESUMO

In the European Union's emissions regulations, limits for solid particles >23 nm are applicable for the type-approval and in use compliance of vehicles. Consequently, particle number (PN) systems are used very often for both research and development of engines and vehicles, both in the laboratory and on the road. The technical specifications of the laboratory and portable on-board systems are not the same resulting in different measurement uncertainties. Furthermore, particles, in contrast to gases, can be lost in the transfer lines making comparisons at different sampling locations difficult. Moreover, the size dependent counting efficiency of the systems can result in high discrepancies when the measured particle sizes are close to the decreasing steep part of the curves. The different sampling locations (tailpipe or dilution tunnel) and thermal pretreatments of the aerosol further enhance the differences. The studies on the measurement uncertainty are scarce, especially for the PN systems measuring from 10 nm that will be introduced in the future regulations. This study quantified the uncertainty sources of the PN systems: (i) due to the technical requirements and the calibrations, (ii) due to the unknown particle sizes during measurement, (iii) due to particle losses from the vehicle to the PN systems at the tailpipe or the dilution tunnel, (iv) other parameters needed for the calculation of the emissions, non-related to the PN systems, e.g. flow and distance. The expanded uncertainty of the 23 nm laboratory systems sampling from the dilution tunnel was estimated to be 32%, with 18% originating from the calibration procedures, while of those sampling from the tailpipe 34%. For the 23 nm portable systems measuring on-road the uncertainty was 39%. The values were 2-8% higher for the 10 nm systems.


Assuntos
Poluentes Atmosféricos , Emissões de Veículos , Poluentes Atmosféricos/análise , Monitoramento Ambiental , Laboratórios , Tamanho da Partícula , Material Particulado/análise , Incerteza , Emissões de Veículos/análise
12.
Sensors (Basel) ; 20(20)2020 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-33066196

RESUMO

For the type approval of compression ignition (diesel) and gasoline direct injection vehicles, a particle number (PN) limit of 6 × 1011 p/km is applicable. Diesel vehicles in circulation need to pass a periodical technical inspection (PTI) test, typically every two years, after the first four years of circulation. However, often the applicable smoke tests or on-board diagnostic (OBD) fault checks cannot identify malfunctions of the diesel particulate filters (DPFs). There are also serious concerns that a few high emitters are responsible for the majority of the emissions. For these reasons, a new PTI procedure at idle run with PN systems is under investigation. The correlations between type approval cycles and idle emissions are limited, especially for positive (spark) ignition vehicles. In this study the type approval PN emissions of 32 compression ignition and 56 spark ignition vehicles were compared to their idle PN concentrations from laboratory and on-road tests. The results confirmed that the idle test is applicable for diesel vehicles. The scatter for the spark ignition vehicles was much larger. Nevertheless, the proposed limit for diesel vehicles was also shown to be applicable for these vehicles. The technical specifications of the PTI sensors based on these findings were also discussed.

13.
PLoS Pathog ; 16(2): e1008311, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-32040500

RESUMO

Pseudomonas aeruginosa is one of the leading causes of nosocomial pneumonia and its associated mortality. Moreover, extensively drug-resistant high-risk clones are globally widespread, presenting a major challenge to the healthcare systems. Despite this, no vaccine is available against this high-concerning pathogen. Here we tested immunogenicity and protective efficacy of an experimental live vaccine against P. aeruginosa pneumonia, consisting of an auxotrophic strain which lacks the key enzyme involved in D-glutamate biosynthesis, a structural component of the bacterial cell wall. As the amounts of free D-glutamate in vivo are trace substances in most cases, blockage of the cell wall synthesis occurs, compromising the growth of this strain, but not its immunogenic properties. Indeed, when delivered intranasally, this vaccine stimulated production of systemic and mucosal antibodies, induced effector memory, central memory and IL-17A-producing CD4+ T cells, and recruited neutrophils and mononuclear phagocytes into the airway mucosa. A significant improvement in mice survival after lung infection caused by ExoU-producing PAO1 and PA14 strains was observed. Nearly one third of the mice infected with the XDR high-risk clone ST235 were also protected. These findings highlight the potential of this vaccine for the control of acute pneumonia caused by this bacterial pathogen.


Assuntos
Infecções por Pseudomonas/imunologia , Pseudomonas aeruginosa/imunologia , Vacinas Atenuadas/imunologia , Administração Intranasal , Animais , Anticorpos Antibacterianos/imunologia , Feminino , Imunidade nas Mucosas , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Pneumonia Bacteriana/imunologia , Pseudomonas aeruginosa/metabolismo , Pseudomonas aeruginosa/patogenicidade , Sistema Respiratório/imunologia , Infecções Respiratórias/imunologia , Vacinas Atenuadas/farmacologia
14.
Environ Res ; 176: 108572, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31377567

RESUMO

Passenger cars are an important source of air pollution, especially in urban areas. Recently, real-driving emissions (RDE) test procedures have been introduced in the EU aiming to evaluate nitrogen oxides (NOx) and particulate number (PN) emissions from passenger cars during on-road operation. Although RDE accounts for a large variety of real-world driving, it excludes certain driving situations by setting boundary conditions (e.g., in relation to altitude, temperature or dynamic driving). The present work investigates the on-road emissions of NOx, NO2, CO, particle number (PN) and CO2 from a fleet of 19 Euro 6b, 6c and 6d-TEMP vehicles, including diesel, gasoline (GDI and PFI) and compressed natural gas (CNG) vehicles. The vehicles were tested under different on-road driving conditions outside boundaries. These included 'baseline' tests, but also testing conditions beyond the RDE boundary conditions to investigate the performance of the emissions control devices in demanding situations. Consistently low average emission rates of PN and CO were measured from all diesel vehicles tested under most conditions. Moreover, the tested Euro 6d-TEMP and Euro 6c diesel vehicles met the NOx emission limits applicable to Euro 6d-TEMP diesel vehicles during RDE tests (168 mg/km). The Euro 6b GDI vehicle equipped with a gasoline particulate filter (GPF) presented PN emissions < 6 × 1011 #/km. These results, in contrast with previous on-road measurements from earlier Euro 6 vehicles, indicate more efficient emission control technologies are currently being used in diesel and gasoline vehicles. At the same time, the results suggest that particular attention should be given to CO and PN emissions of certain types of vehicles when driven under dynamic conditions, and possibly additional work is necessary. In particular, the emissions of CO (measured in this study during the regulated RDE test, but without an emission limit associated to it) or PN from PFI vehicles (presently not covered by the Euro 6 standard) showed elevated results in some occasions. Emissions of CO were up to 7.5 times higher when the more dynamic tests were conducted and the highest PN emissions were measured from a PFI gasoline vehicle during dynamic driving. Although based on a limited sample of cars, our work points to the relevance of a technology- and fuel-neutral approach to vehicle emission standards, whereby all vehicles must comply with the same emission limits for all pollutants.


Assuntos
Poluentes Atmosféricos , Poluição do Ar/estatística & dados numéricos , Automóveis/estatística & dados numéricos , Emissões de Veículos/análise , Gasolina , Veículos Automotores
15.
Sci Total Environ ; 543(Pt A): 670-682, 2016 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-26615485

RESUMO

Despite the ~30% emission decrease of the main tropospheric ozone (O3) precursors in Spain in the 2001-2012 period, the O3 concentration in summer still exceeds the target value for the protection of the human health of the Air Quality Directive (2008/50/EC). On-road transport is the main anthropogenic contributor to O3 precursor's emissions in Madrid and Barcelona metropolitan areas (65%/59% of NOx, 40%/33% of NMVOC, and 67%/85% of CO emissions) but this contribution to O3 formation is not well understood. The present work aims at increasing the understanding on the role of on-road transport emissions from main Spanish urban areas in O3 dynamics over Spain under typical circulation types. For that purpose, the Integrated Source Apportionment Method is used within the CALIOPE modelling system (WRF/CMAQ/HERMES/BSC-DREAM8b). The results indicate that the daily maximum O3 concentration attributed to the on-road transport emissions from Madrid (O3T-MAD) and Barcelona metropolitan areas (O3T-BCN) contribute up to 24% and 8% to total O3 concentration, respectively, within an area of influence of 200 km. The contribution of O3T-MAD and O3T-BCN is particularly significant (up to 80-100 µg m(-3) in an hour) to the O3 concentration peak during the central hours of the day in the high O3 concentration season (April-September). The maximum O3T-MAD concentration is calculated within the metropolitan area of Madrid but the plume, channelled by the Tajo and the Henares valleys, affects large areas of the Iberian Peninsula. The O3T-BCN plume is more driven by sea-land and mountain-valley breezes than by the synoptic advection and its maximum concentration is usually registered over the Mediterranean Sea. The O3 concentration transported long-range to the Iberian Peninsula is significant in the area of influence of Madrid and Barcelona, being maxima under cold (70-96%) and minima in warm circulation types (35-70%).

16.
Sci Total Environ ; 541: 701-713, 2016 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-26433330

RESUMO

Emissions of SO2 and NO2 from coal-fired power plants are a significant source of air pollution. In order to typify the power plants' plumes dynamics and quantify their contribution to air quality, a comprehensive characterisation of seven coal-fired power plant plumes has been performed under six representative circulation types (CTs) identified by means of a synoptic classification over the Iberian Peninsula. The emission and the transport of SO2 and NO2 have been simulated with the CALIOPE air quality forecasting system that couples the HERMES emission model for Spain and WRF and CMAQ models. For the facilities located in continental and Atlantic areas (As Pontes, Aboño, and Compostilla) the synoptic advection controls pollutant transport, however for power plants located along the Mediterranean or over complex-terrains (Guardo, Andorra, Carboneras, and Los Barrios), plume dynamics are driven by a combination of synoptic and mesoscale mountain-valley and sea-land breezes. The contribution of power plants to surface concentration occurs mainly close to the source (<20 km) related to a fumigation process when the emission injection takes place within the planetary boundary layer reaching up to 55 µg SO2 m(-3) and 32 µg NO2 m(-3). However, the SO2 and NO2 plumes can reach long distances (>250 km from the sources) especially for CTs characterised by Atlantic advection.

17.
Med. clín (Ed. impr.) ; 135(7): 300-305, sept. 2010. tab
Artigo em Espanhol | IBECS | ID: ibc-83611

RESUMO

Fundamento y objetivoLa enfermedad de Fabry (EF) es una enfermedad hereditaria con manifestaciones clínicas multisistémicas.Fundamento y objetivoEl diagnóstico suele ser tardío, por lo que la afectación orgánica puede ser irreversible. La detección precoz de la enfermedad, en especial la afectación cardiaca, es crucial para que los pacientes puedan beneficiarse del tratamiento de reemplazo enzimático.Fundamento y objetivoEl objetivo de este estudio fue valorar si la resonancia magnética con secuencia de realce tardío con gadolinio puede ser útil para la detección precoz de la afectación cardiaca.Pacientes y métodosSe estudió a 20 pacientes (9 varones) con diagnóstico de EF a quienes se les realizó ecografía, Doppler tisular (DTI) y resonancia magnética.Pacientes y métodosSe consideró hipertrofia un grosor del septo y la pared posterior mayor o igual a 12mm. El DTI fue alterado con una velocidad de las ondas sistólicas, las ondas diastólicas tempranas o las ondas diastólicas tardías del anillo septal y lateral menor de 8cm/s.Pacientes y métodosSe realizó la resonancia magnética con secuencias de realce tardío con gadolinio.ResultadosLos pacientes incluidos se dividieron en 3 grupos según los resultados obtenidos: 1) DTI normal, sin hipertrofia del ventrículo izquierdo (HVI) 2) DTI alterado, sin HVI 3) DTI alterado e HVIResultadosLa resonancia detectó realce tardío en un paciente (DTI alterado e HVI).ConclusionesEl DTI es la única herramienta de diagnóstico precoz de afectación cardiaca en la EF. La resonancia magnética podría ser de gran valor para la estratificación diagnóstica.


Background and objectivesEarly detection of cardiac symptoms is of major interest in Fabry's disease (FD) in order to gain access to enzyme replacement therapy. Echo-Doppler tissular imaging (TDI) has been used as a cardiologic early marker in FD.ObjectivesThis study is intended to determine whether the cardiac magnetic resonance is as useful tool as TDI for the early detection of cardiac affectation in FD.Patients and methodsEchocardiography, tissue Doppler and Cardio magnetic resonance was performed in 20 patients with confirmed Fabry Disease.Patients and methodsLeft ventricular hypertrophy was defined as septum and left ventricular posterior wall thickness ≥12mm.Patients and methodsAn abnormal TDI velocity was defined as (Sa), (Ea) and/or (Aa) velocities <8cm/s at either the septal or lateral corner.ResultsTwenty patients included in the study were divided into three groups: 1. Those without left ventricular hypertrophy nor tissue Doppler impairment 2. Those without left ventricular hypertrophy and tissue Doppler impairment 3. Those with left ventricular hypertrophy and Tissue Doppler impairment.ResultsLate gadolinium enhancement was found in only one patient, who has already altered DTI and LVH.


Assuntos
Humanos , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Doença de Fabry/complicações , Espectroscopia de Ressonância Magnética , Hipertrofia Ventricular Esquerda/diagnóstico , Doença de Fabry/diagnóstico , Gadolínio , Hipertrofia Ventricular Esquerda/etiologia
18.
Med Clin (Barc) ; 135(7): 300-5, 2010 Sep 04.
Artigo em Espanhol | MEDLINE | ID: mdl-20605170

RESUMO

BACKGROUND AND OBJECTIVES: Fabry disease is a hereditary disorder. Clinical manifestations are multisystemic. The majority of the patients remain undiagnosed until late in life, when alterations could be irreversible. Early detection of cardiac symptoms is of major interest in Fabry's disease (FD) in order to gain access to enzyme replacement therapy. Echo-Doppler tissular imaging (TDI) has been used as a cardiologic early marker in FD. OBJECTIVES: This study is intended to determine whether the cardiac magnetic resonance is as useful tool as TDI for the early detection of cardiac affectation in FD. PATIENTS AND METHODS: Echocardiography, tissue Doppler and Cardio magnetic resonance was performed in 20 patients with confirmed Fabry Disease. Left ventricular hypertrophy was defined as septum and left ventricular posterior wall thickness ≥12 mm. An abnormal TDI velocity was defined as (Sa), (Ea) and/or (Aa) velocities <8 cm/s at either the septal or lateral corner. Late phase gadolinium-enhanced images sequences were obtained using magnetic resonance. RESULTS: Twenty patients included in the study were divided into three groups: 1. Those without left ventricular hypertrophy nor tissue Doppler impairment 2. Those without left ventricular hypertrophy and tissue Doppler impairment 3. Those with left ventricular hypertrophy and Tissue Doppler impairment. Late gadolinium enhancement was found in only one patient, who has already altered DTI and LVH. CONCLUSION: Tissue Doppler imaging (TDI) is the only diagnostic tool able to provide early detection of cardiac affectation in patients with FD. Magnetic resonance provides information of the disease severity in patients with LVH, but can not be used as an early marker of cardiac disease in patients with FD. However MRI could be of great value for diagnostic stratification.


Assuntos
Cardiopatias/diagnóstico , Imageamento por Ressonância Magnética , Adulto , Diagnóstico Precoce , Doença de Fabry/complicações , Feminino , Cardiopatias/diagnóstico por imagem , Cardiopatias/etiologia , Humanos , Masculino , Ultrassonografia
19.
Rev. chil. obstet. ginecol ; 56(1): 35-7, 1991. tab
Artigo em Espanhol | LILACS | ID: lil-104749

RESUMO

Se efectúa estimulación vibroacústica intraparto a pacientes cuya monitorización externa de la frecuencia fetal resultó patológica. Se correlaciona el resultado de ésta estimulación con Apgar, presencia de meconio y pH de cordón umbilical. Se concluye que en relación al pH, la estimulación vibroacústica tiene una sensibilidad de 83,3%, una especificidad de 81,3%y un valor predictivo positivo de 62,5%. Se recomienda el uso de estimulación vibroacústica en aquellos casos en que la monitorización sea patológica y no se pueda utilizar monitorización interna ni se pueda obtener pH de cuero cabelludo fetal, para asegurar el buen estado fetal


Assuntos
Estimulação Acústica/métodos , Monitorização Fetal/efeitos adversos , Trabalho de Parto/fisiologia , Filipinas
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