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1.
Exp Parasitol ; 205: 107733, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31408623

RESUMO

Toxoplasma gondii is a ubiquitous protozoan of major medical and veterinary importance. Its treatment is difficult since the available drugs have severe side effects and reactivation may occur anytime. Vaccination with irradiated parasites exhibits ideal characteristics for vaccine development. In our experimental mice model, the protection against challenge with the virulent RH strain was assessed, using 255Gy irradiated tachyzoites. Eighty mice were allocated into 3 groups: naive control group, challenged with virulent RH tachyzoites group and a third group which is challenged with 1 × 106 irradiated tachyzoites, administered as two biweekly doses intraperitoneally. Protection was tested by challenging vaccinated mice with the virulent type RH tachyzoites 30 days after the 2nd vaccination dose. The assessment was built on qualitative clinical, quantitative parasitological, histopathological parameters and measurement of serum Nitric Oxide (NO). The results showed prolonged survival rate, absence of tachyzoites in the peritoneal aspirate by counting, absence of tachyzoites in all examined organs by impression smears, amelioration of histopathological changes in the liver, spleen, brain and lung specimens and increase of the serum NO level in the vaccinated group. Therefore, we propose that irradiated Toxoplasma tachyzoites confer protection for challenged mice and could be an alternative immunization schedule for vaccine development especially for who are at risk of severe immunosuppression.


Assuntos
Toxoplasma/imunologia , Toxoplasma/efeitos da radiação , Toxoplasmose Animal/prevenção & controle , Toxoplasmose Animal/parasitologia , Vacinação/métodos , Animais , Líquido Ascítico/parasitologia , Encéfalo/parasitologia , Encéfalo/patologia , Colorimetria , Feminino , Raios gama , Fígado/parasitologia , Fígado/patologia , Pulmão/parasitologia , Pulmão/patologia , Camundongos , Óxido Nítrico/análise , Baço/parasitologia , Baço/patologia , Taxa de Sobrevida , Toxoplasmose Animal/imunologia , Toxoplasmose Animal/mortalidade
2.
Phys Chem Chem Phys ; 21(35): 19083-19091, 2019 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-31432839

RESUMO

The development of new techniques or instruments for detecting and accurately measuring biomarker concentrations in living organisms is essential for early diagnosis of diseases, and for tracking the effectiveness of treatments. In chronic diseases, such as asthma, precise phenotyping can help predict the response of patients to treatments and reduce the risk of complications. Fractional exhaled nitric oxide (FeNO) is a positive biomarker for eosinophilic asthma in humans, and it can be directly detected in the respiratory tract, at very low and volatile concentrations, which makes real-time measurement a challenge. This work describes the first-principles design and characterization of a molecular- and back-gated electronic field-effect transistor device for the detection and measurement of ultra-low FeNO concentrations (pM-nM) from a person' s exhaled breath, as a cost-efficient alternative to the slower and more expensive techniques based on off-line sputum characterization via mass spectrometry. The proposed device uses a partially oxidized phosphorene semiconducting channel material for FeNO detection, allowing nM L-1 concentration measurements of this analyte in an array configuration with an effective sensing surface area of 8.775 µm2, which results in a predicted limit of detection (LOD) of 19 nM L-1. In spite of the limited stability of phosphorene in oxygen-rich and humid environments, the proposed device would be practical for mobile applications with disposable sensors.


Assuntos
Biomarcadores/análise , Testes Respiratórios/instrumentação , Testes Respiratórios/métodos , Óxido Nítrico/análise , Asma/diagnóstico , Expiração , Humanos , Limite de Detecção
3.
Neumol. pediátr. (En línea) ; 14(2): 76-80, jul. 2019. ilus
Artigo em Espanhol | LILACS | ID: biblio-1014992

RESUMO

Primary ciliary dyskinesia is a congenital disorder due to abnormal motile ciliary function, especially in the airway epithelium. The mucociliary clearance is impaired, producing reoccurring respiratory tract infections, usually resulting in bronchiectasis as an adult. Patients also have frequent ear and sinus infections and almost 50% of them have situs inversus. Diagnosis of primary ciliary dyskinesia is difficult because there is not a single gold standard test, resulting in the need of a multi-test approach. Until recently in our country we only had transmission electron microscopy, but nasal nitric oxide and high speed video microscopy are now available. In this article we will detail the most important clinical characteristics that make us suspect the presence of primary ciliary dyskinesia at different ages and the methods available for its diagnosis.


La discinesia ciliar primaria es una enfermedad congénita debida a una alteración del movimiento normal de los cilios, especialmente a nivel del epitelio respiratorio. Esto se traduce en una alteración del clearance mucociliar lo que predispone al paciente a tener infecciones respiratorias repetidas, terminando en la aparición de bronquiectasias en la edad adulta. También son frecuentes las infecciones repetidas de oídos y cavidades perinasales. La presencia de situs inverso puede verse en hasta en 50% de los pacientes con esta enfermedad. El diagnóstico de discinesia ciliar primaria es difícil ya que no existe un examen que sea considerado patrón de oro, por lo que se requiere la realización de distintos exámenes. En nuestro país hasta hace poco tiempo solo contábamos con la microscopía electrónica, pero recientemente se ha sumado la medición de óxido nítrico nasal y la videomicroscopía de alta velocidad. En el presente artículo se detallarán las características clínicas más importantes que hacen sospechar la presencia de DCP en las distintas edades y los métodos disponibles para su diagnóstico.


Assuntos
Humanos , Recém-Nascido , Pré-Escolar , Adulto , Síndrome de Kartagener/diagnóstico , Síndrome de Kartagener/genética , Síndrome de Kartagener/terapia , Cílios/ultraestrutura , Biópsia , Algoritmos , Testes Genéticos , Microscopia de Vídeo , Microscopia Eletrônica de Transmissão , Óxido Nítrico/análise
4.
Ann Otol Rhinol Laryngol ; 128(11): 1081-1085, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31271036

RESUMO

OBJECTIVES: The diagnosis of primary ciliary dyskinesia (PCD) is often delayed in part related to the limitations of the available diagnostic tests. We present 3 cases of PCD diagnosed using an exhaled nitric oxide (eNO) measurement. METHODS: Three cases with a clinical phenotype consistent with PCD were evaluated using an eNO assay with additional transmission electron microscopy (TEM) and/or genetic panel testing. RESULTS: One male and 2 female patients presented with common symptoms included recurrent respiratory infection from early childhood and a history of neonatal respiratory distress as term newborn. Two of them had situs inversus totalis. Fractional eNO measurement revealed extremely low NO levels, and subsequently, TEM analysis confirmed ciliary ultrastructural defects in all patients. One patient had compound heterozygous mutation of the PCD-causative gene (DNAH5) identified using next generation sequencing. CONCLUSION: Our report stresses the reliability of eNO measurement in the diagnosis of PCD, accompanied by clinical phenotypes and additional diagnostic tools, such as TEM analysis and genetic testing.


Assuntos
Cílios/ultraestrutura , Transtornos da Motilidade Ciliar/diagnóstico , Óxido Nítrico/análise , Adolescente , Endoscopia , Expiração , Feminino , Humanos , Masculino , Microscopia Eletrônica de Transmissão , Pessoa de Meia-Idade , Tomografia Computadorizada por Raios X , Adulto Jovem
5.
J Immunoassay Immunochem ; 40(5): 502-514, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31339439

RESUMO

Both Behçet's disease (BD) and major depressive disorder (MDD) are diseases associated with nitric oxide (NO). We hypothesized that the comorbidity of MDD affects the levels of NO in BD. In this study, we investigate whether there was a difference in NO levels among BD patients with accompanying MDD, BD patients with no depressive symptoms and healthy control group. There was a significant difference in NO levels among BD and control group (P < 0.05). Also, there was a significant difference between the BD group with MDD and BD group without psychiatric comorbidity in terms of NO levels (P < 0.05). This study is interesting as it demonstrates that accompanying psychiatric comorbidity puts an additional NO burden on the shoulders of BD patients.


Assuntos
Síndrome de Behçet/metabolismo , Síndrome de Behçet/psicologia , Transtorno Depressivo Maior/metabolismo , Óxido Nítrico/análise , Adulto , Síndrome de Behçet/epidemiologia , Comorbidade , Transtorno Depressivo Maior/epidemiologia , Feminino , Humanos , Masculino
6.
Biomed Khim ; 65(3): 245-250, 2019 Apr.
Artigo em Russo | MEDLINE | ID: mdl-31258149

RESUMO

The content of vasoactive compounds and arachidonic acid in the placenta and amniotic fluid was studied in full-term (39-40 weeks) physiological pregnancy and preeclampsia (PE). The content of metabolites of nitric oxide (NOx), endothelin-1, thromboxane B2 (TxB2), prostacycline (PGI2) and arachidonic acid was estimated using spectrophotometric, immunoenzyme methods and gas-liquid chromatography. It was found that in PE the content of vasoconstrictors, of endothelin and TxB2, increased in the placenta and amniotic fluid, while the content of vasodilators, PGI2 and NOx decreased. Despite the same directionality of changes in both studied objects, the degree of changes differed and was more pronounced in the placenta. A direct or inverse correlative relationship was found between various vasoactive components (depending on their effect on vascular tone). In the case of arachidonic acid changes in its content in PE correlated with the level of vasoactive compounds, the source of which it is. The revealed differences in the ratio of vasoactive components obviously play a pathogenetic role in the development of PE and its subsequent complications.


Assuntos
Líquido Amniótico/química , Ácido Araquidônico/análise , Placenta/química , Pré-Eclâmpsia , Endotelina-1/análise , Feminino , Humanos , Óxido Nítrico/análise , Gravidez , Prostaglandinas I/análise , Tromboxano B2/análise
7.
Vet Microbiol ; 233: 85-92, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31176417

RESUMO

Muscovy duck reovirus (MDRV) causes serious immunodeficiency in the intestinal mucosa, although the underlying histopathological mechanisms remain unclear. Thus, we investigated the impact of MDRV infection on intestinal morphology using hematoxylin and eosin staining. Immune-related cells were also quantified by staining with hematoxylin and eosin, toluidine blue, and periodic acid-Schiff stain, or by immunohistochemistry and cytochemistry for lectin. Similarly, CD4+ and CD8+ cells were quantified by flow cytometry, and the expression of several immune-related molecules was quantified by radioimmunoassay. We found that MDRV clearly damaged the intestinal mucosa, based on tissue morphology, villus length, villus width, intestinal thickness, villus height/crypt depth ratio, and villus surface area. MDRV also altered the density or distribution of lymphocytes, mastocytes, and goblet cells in the small intestinal mucosa, as well as microfold cells in Peyer's patches. In addition, MDRV markedly depleted CD4+ cells from the intestinal mucosa and lowered the CD4+:CD8+ ratio in peripheral blood. Moreover, MDRV diminished the levels of secretory IgA and mucosal addressin cell adhesion molecule-1 (p < 0.01), but elevated those of histamine and nitric oxide (p < 0.01 or p < 0.05). Finally, MDRV significantly suppressed IL-1ß, IL-4, IL-5, and IL-8 levels (p < 0.01 or p < 0.05) mid-infection. Collectively, our data suggest that MDRV severely damages the structure and function of the intestinal mucosa by modulating immune cells and immune-related factors, thus leading to local immunodeficiency. Our findings lay the foundation for further research on the pathogenesis of MDRV.


Assuntos
Mucosa Intestinal/imunologia , Mucosa Intestinal/patologia , Intestino Delgado/virologia , Orthoreovirus Aviário/imunologia , Infecções por Reoviridae/imunologia , Fatores Etários , Animais , Contagem de Linfócito CD4 , Citocinas/imunologia , Patos/virologia , Duodeno , Fibroblastos/virologia , Histamina/análise , Imunoglobulina A Secretora/análise , Intestino Delgado/imunologia , Óxido Nítrico/análise , Orthoreovirus Aviário/patogenicidade , Doenças das Aves Domésticas/virologia , Infecções por Reoviridae/patologia , Carga Viral
8.
Eur J Med Chem ; 179: 182-195, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31254920

RESUMO

A series of (1,2,4)triazole[4,3-a]pyridine (TZP) derivatives have been designed and synthesized. Compound 8d was identified as having the most potent inhibitory activity on NO release in response to lipopolysaccharide (LPS) stimulation and inhibition of the migration induced by MCP-1 protein on RAW264.7 macrophages. Based on the screening data, an immunofluorescence assay and a real-time qPCR assay were conducted, indicating that compound 8d suppressed NF-κB p65 translocation and expression of inflammatory genes by concanavalin A (Con A)-induced RAW264.7 macrophages. More importantly, 8d also exhibited potent efficacy, alleviating Con A-induced hepatitis by downregulating the levels of plasma alanine transaminase (ALT), aspartate transaminase (AST) and inflammatory infiltration in a mouse autoimmune hepatitis (AIH) model. In addition, the flow cytometry (FCM) data showed that compound 8d inhibited the accumulation of MDSCs in the liver of Con A-induced mice. These findings raise the possibility that compound 8d might serve as a potential agent for the treatment of AIH.


Assuntos
Concanavalina A/antagonistas & inibidores , Hepatite/tratamento farmacológico , Piridinas/farmacologia , Triazóis/farmacologia , Animais , Sobrevivência Celular , Células Cultivadas , Concanavalina A/metabolismo , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Desenho de Drogas , Feminino , Hepatite/metabolismo , Humanos , Lipopolissacarídeos/antagonistas & inibidores , Lipopolissacarídeos/farmacologia , Camundongos , Camundongos Endogâmicos BALB C , Estrutura Molecular , Óxido Nítrico/análise , Óxido Nítrico/biossíntese , Piridinas/síntese química , Piridinas/química , Células RAW 264.7 , Relação Estrutura-Atividade , Triazóis/síntese química , Triazóis/química
9.
Mar Pollut Bull ; 142: 525-532, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31232333

RESUMO

Ocean-going ships are mostly driven by high­sulfur heavy fuel oil, which poses public health and environmental concerns. Emission control areas (ECA) have been developed for the regulatory control of the sulfur content in fuel. We tracked 28 sample vessels that entered and exited Shanghai Port, to understand how air pollutants, including oxysulfides (SOx), nitric oxide (NOx), and particulate matter smaller than 10 µm (PM10), would change under the ECA regulations. Emission reductions vary with the types and sizes of the ships. In our sample pool, oil/chemical tankers and container ships have the highest decline rates of SOx emissions at 26.8%-56.4% and 17.4%-56.6%, respectively. Cruise ships, container ships, and liquefied gas carriers occupy the highest share ratios of pollutant emissions in the sample pool because of the higher average gross tonnage and correspondingly higher-rated power of the ships' main engines. As expected, SOx and PM10 emissions under hoteling conditions (operations while stationary at dock) can be considerably reduced by switching to low-sulfur fuel. Using fuel with the much lower sulfur content of 0.1% m/m in the ECA, the SOx and PM10 emissions of our sample pool could be reduced considerably by up to 94.4% and 78.3%, respectively, compared to the 0.5% m/m sulfur content used during ship hoteling.


Assuntos
Poluentes Atmosféricos/análise , Poluição do Ar/prevenção & controle , Óleos Combustíveis , Navios , Poluição do Ar/análise , China , Monitoramento Ambiental , Óxido Nítrico/análise , Oceanos e Mares , Material Particulado/análise , Enxofre , Óxidos de Enxofre/análise , Emissões de Veículos/análise
10.
Anal Chim Acta ; 1067: 88-97, 2019 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-31047153

RESUMO

Nitric oxide (NO), a ubiquitous gasotransmitter which plays critical roles in cardiovascular, nervous, and immune systems related diseases, is closely related in the physiological and pathological processes of mitochondria and lysosomes. Thus, monitoring NO in mitochondria or lysosomes is very meaningful for NO related chemical biology. Herein, we rationally designed four NO probes, BDP-NO, Mito-NO-T, Mito-NO and Lyso-NO, based on BODIPY dye substituted at meso position with 5-amino-2-methoxy-phenyl scaffold. These four probes all showed fast fluorescence off-on response toward NO with excellent selectivity and high sensitivity with the detection limit of BDP-NO to reach 5.7 nM. We introduced triphenylphosphonium and morpholine moieties onto BODIPY scaffold respectively to enable organelle-targetability. MTT and flow cytometry assay demonstrated that the probes exhibited low cytotoxicity, which was beneficial to the biological application in living cells. Confocal fluorescence microscopy experiments confirmed excellent mitochondria targeting for Mito-NO and lysosome-targeting with Lyso-NO for the detection of NO in living cells.


Assuntos
Compostos de Boro/química , Corantes Fluorescentes/química , Lisossomos/química , Mitocôndrias/química , Óxido Nítrico/análise , Apoptose/efeitos dos fármacos , Compostos de Boro/síntese química , Compostos de Boro/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Corantes Fluorescentes/síntese química , Corantes Fluorescentes/farmacologia , Células HeLa , Humanos , Lisossomos/metabolismo , Microscopia Confocal , Mitocôndrias/metabolismo , Estrutura Molecular , Óxido Nítrico/metabolismo , Imagem Óptica , Células Tumorais Cultivadas
11.
Talanta ; 200: 472-479, 2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31036211

RESUMO

A new kind of nanoscale MOFs probe for nitric oxide (NO) sensing has been successfully constructed by a one-pot strategy, in which the chemically stable UiO-66 crystal structure was achieved using platinum meso-tetra(4-carboxyphenyl)porphyrin (Pt-TCPP), 1,1,2,2-Tetra(4-carboxylphenyl)ethylene (H4TCPE) and 1,4-dicarboxybenzene (BDC) as co-linkers (Pt-TCPP/H4TCPE@UiO-66). Pt-TCPP was verified to serve as a signal reporter in NO sensing fields for the first time while H4TCPE worked as a luminescence reference to build a ratiometric sensor. The integration of luminescent dyes in nanoscale MOFs effectively avoided their aggregation-caused quenching effect and poor aqueous dispersibility to rationalize NO detection in the aqueous phase. The obtained Pt-TCPP/H4TCPE@UiO-66 nanoparticles (NPs) exhibited an excellent sensing property toward NO with an ultrahigh linear correlation of the Stern-Volmer equation and a rapid response time as short as 2 min. Moreover, the elaborated sensor could work under a wide pH window (7.4, 5.6 and 0) and the limit of detection (LOD) reached as low as 0.1420 µg mL-1. The specificity of the obtained Pt-TCPP/H4TCPE@UiO-66 NPs toward NO sensing was scarcely affected by other possibly coexistent species in biological system. The in vitro monitoring for NO in living cells was also testified with these Pt-TCPP/H4TCPE@UiO-66 NPs.


Assuntos
Sobrevivência Celular , Substâncias Luminescentes/química , Estruturas Metalorgânicas/química , Metaloporfirinas/química , Óxido Nítrico/análise , Platina/química , Zircônio/química , Citometria de Fluxo , Células HeLa , Humanos , Medições Luminescentes , Imagem Óptica , Tamanho da Partícula , Propriedades de Superfície
12.
Braz Oral Res ; 33: e035, 2019 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-31038569

RESUMO

Eugenia dysenterica is a Brazilian tree investigated for its properties and bioactive compounds, which are believed to have both pharmacological and phytochemical therapeutic effects. The leaves of this tree contain tannins, flavonoids, terpenes, and saponins, with reportedly beneficial effects to the human body. Despite these therapeutic applications, its effects have never been tested on oral tissues. Therefore, the aim of the present study was to evaluate the cytotoxic and antioxidant effects and the anti-inflammatory and repair properties of the acetone fraction of E. dysenterica on primary culture of human gingival fibroblasts and on the immortalized murine macrophage cell line (RAW 264.7). For this purpose, a metabolic activity assay, a wound healing assay, a nitric oxide assay, and RT-qPCR were performed. The assays revealed a cytoprotective effect of this plant, suggested by the increase in the expression of SOD1 and NRF2. An antioxidant potential effect was observed in the DPPH• assay. However, the fraction of E. dysenterica did not show anti-inflammatory activity. In conclusion, Eugenia dysenterica may promote cytoprotection when associated with chlorhexidine digluconate because of its antioxidant effect. However, additional studies are necessary on other human dental tissues using other parts of the plant in order to develop a possible mouthwash to assist patients with oral disorders.


Assuntos
Anti-Inflamatórios/farmacologia , Antioxidantes/farmacologia , Eugenia/química , Fibroblastos/efeitos dos fármacos , Gengiva/citologia , Extratos Vegetais/farmacologia , Animais , Brasil , Células Cultivadas , Clorexidina/análogos & derivados , Clorexidina/farmacologia , Humanos , Camundongos , Óxido Nítrico/análise , Folhas de Planta/química , Células RAW 264.7 , Valores de Referência , Reprodutibilidade dos Testes , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fatores de Tempo , Cicatrização/efeitos dos fármacos
13.
Environ Sci Pollut Res Int ; 26(19): 19540-19548, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31077045

RESUMO

Ferrous chelates (FeIIEDTA) can effectively absorb NO, but the regeneration of them usually consumes large amounts of organic matter or energy. In this study, a new approach to regenerate NO absorbed ferrous chelates with simultaneous electricity generation was investigated by a microbial fuel cell (MFC). The performance and mechanisms of FeIIEDTA regeneration were evaluated in the cathode of MFC reactor with and without the presence of microorganisms (referring to biocathode and abiotic cathode), respectively. It was found that FeIIEDTA-NO and FeIIIEDTA could be used as the cathode electron acceptors in MFC. Low pH (pH = 5) was beneficial to electricity generation and FeIIIEDTA/FeIIEDTA-NO reduction by the abiotic cathode. The biocathode performed better in electricity generation and FeIIEDTA regeneration, and achieved a FeIIIEDTA reducing rate of 0.34 h-1 and a FeIIEDTA-NO reducing rate of 0.97 L mmol-1 h-1, which are much higher that than those for the abiotic cathode (0.23 h-1 for FeIIIEDTA, 0.44 L mmol-1 h-1 for FeIIEDTA-NO). This was likely because the activation polarization loss and over cathode potential were reduced as a result of the catalytic activity of NO and iron reducing bacteria.


Assuntos
Fontes de Energia Bioelétrica/microbiologia , Quelantes/química , Ácido Edético/química , Compostos Férricos/química , Compostos Ferrosos/química , Óxido Nítrico/análise , Absorção Fisico-Química , Comamonas/isolamento & purificação , Cupriavidus/isolamento & purificação , Eletricidade , Eletrodos , Microbiota , Oxirredução
14.
Environ Sci Pollut Res Int ; 26(17): 17821-17833, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31037527

RESUMO

A bibliometric method was used to evaluate the global scientific publications about sulfur oxides and nitric oxides released by coal-fired flue gas and vehicle exhaust from 1995 to 2018 and to provide insights into the characteristics of the articles and tendencies that may exist in the publications. Performance of publications, research tendency, and hotspots were analyzed. The article number had an explosive growth in 2004 and, then, began to grow steadily. China had an absolutely advantage in publication quantities; however, America had a leading position considering publication cited times. The simultaneous removal of mercury, particulate matter, and CO2 was a research hotpot in sulfur oxide and nitric oxide control process; oxidation, absorption, and catalytic reduction were the central control methods that had the most strength in relation with sulfur dioxide and nitric oxide. Considering the study of traditional flue gas pollutant control method (limestone-gypsum method, selective catalytic reduction, etc.) was perfection, it was speculated that adsorption by ionic liquid, electricity charging, advanced oxidation progress, and multi-pollutant removal, simultaneously, would be the new research orientation in flue gas pollutant control. One of the hot points of controlling the vehicle exhaust was the application of the "green energy" biodiesel; lots of keywords concerning human health suggested that quite a lot studies were focused on the health hazard brought by sulfur oxides and nitric oxide.


Assuntos
Poluentes Atmosféricos/análise , Monitoramento Ambiental , Óxido Nítrico/análise , Centrais Elétricas , Óxidos de Enxofre/análise , Poluição do Ar/estatística & dados numéricos , Bibliometria , Catálise , China , Carvão Mineral , Mercúrio/análise , Oxirredução , Óxidos , Material Particulado , Compostos de Enxofre , Dióxido de Enxofre , Emissões de Veículos/análise
15.
Environ Pollut ; 252(Pt A): 31-38, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31146236

RESUMO

Diesel vehicles are a major source of air pollutants in cities and have caused significant health risks to the public globally. This study used both on-road remote sensing and transient chassis dynamometer to characterise emissions of diesel light goods vehicles. A large sample size of 183 diesel vans were tested on a transient chassis dynamometer to evaluate the emission levels of in-service diesel vehicles and to determine a set of remote sensing cutpoints for diesel high-emitters. The results showed that 79% and 19% of the Euro 4 and Euro 5 diesel vehicles failed the transient cycle test, respectively. Most of the high-emitters failed the NO limits, while no vehicle failed the HC limits and only a few vehicles failed the CO limits. Vehicles that failed NO limits occurred in both old and new vehicles. NO/CO2 ratios of 57.30 and 22.85 ppm/% were chosen as the remote sensing cutpoints for Euro 4 and Euro 5 high-emitters, respectively. The cutpoints could capture a Euro 4 and Euro 5 high-emitter at a probability of 27% and 57% with one snapshot remote sensing measurement, while only producing 1% of false high-emitter detections. The probability of high-emitting events was generally evenly distributed over the test cycle, indicating that no particular driving condition produced a higher probability of high-emitting events. Analysis on the effect of cutpoints on real-driving diesel fleet was carried out using a three-year remote sensing program. Results showed that 36% of Euro 4 and 47% of Euro 5 remote sensing measurements would be detected as high-emitting using the proposed cutpoints.


Assuntos
Poluentes Atmosféricos/análise , Poluição do Ar/análise , Monitoramento Ambiental/métodos , Tecnologia de Sensoriamento Remoto/métodos , Emissões de Veículos/análise , Condução de Veículo , Dióxido de Carbono/análise , Cidades , Gasolina/análise , Veículos Automotores , Óxido Nítrico/análise
16.
Wiad Lek ; 72(4): 622-626, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31055544

RESUMO

OBJECTIVE: Introduction: The combination of asthma and allergic rhinitis can affect the mutual encumbrance to which other pathogenetic mechanisms join, which worsen the course of both diseases. The aim of work is to analyze the features of the genotype and phenotype in patients with a co-morbidity of asthma and allergic rhinitis. PATIENTS AND METHODS: Materials and methods: In order to detect the features of asthma and allergic rhinitis, 115 patients were examined. Patients were divided into two groups: the first included 58 patients with allergic asthma and allergic rhinitis co-morbidity, the second - 57 patients with non-allergic asthma morbidity. RESULTS: Results: For the group of patients with allergic asthma with concomitant allergic rhinitis, the first manifestation of allergy in childhood is characteristic (allergic rhinitis, hay fever, atopic dermatitis). For this group of patients characterized by a heavy family allergic history. Symptoms of allergic rhinitis aggravate the course of asthma. Characteristic correlation of symptoms of allergic rhinitis with distal obstruction and pronounced lability of bronchi. In these patients, the total increase in IgE and blood eosinophilia, in 1,5 times increased blood histamine and the level of exhaled NO2 have been increased. Also, asthma control with concomitant allergic rhinitis was significantly worse than in an isolated asthma group (p <0.05). CONCLUSION: Conclusion: The obtained data allow to distinguishing the phenotype of patients with asthma and allergic rhinitis co-morbidity.


Assuntos
Asma/complicações , Dermatite Atópica/complicações , Rinite Alérgica Perene/complicações , Rinite Alérgica Sazonal/complicações , Comorbidade , Eosinofilia , Histamina/sangue , Humanos , Imunoglobulina E/sangue , Óxido Nítrico/análise
17.
Environ Pollut ; 250: 856-862, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31085471

RESUMO

Urea deep placement (UDP) increases nitrogen use efficiency (NUE) and crop yields while reducing nitrogen (N) losses to the environment. However, studies on its environmental impacts on nitric oxide (NO) emissions are still limited. Therefore, we conducted a greenhouse experiment to quantify the NO emissions from a rice-wheat system. NO emissions were measured from three N fertilizer treatments - control (no N), UDP, and broadcast prilled urea (PU) - using an automated gas sampling and analysis system continuously for a rice-wheat cropping cycle. In rice, UDP was tested under two water regimes - continuous flooding (CF) and alternate wetting and drying (AWD). Fertilizer treatments had significant effects (p < 0.05) on NO emissions. UDP with AWD irrigation increased NO emissions (3.41 g N ha-1) (p < 0.05) by 2.5-times compared to UDP with CF (1.35 g N ha-1). But emissions were similar between UDP and broadcast PU under the CF water regime. In wheat, the application of N fertilizer - regardless of application methods - increased NO emissions (615 g N ha-1, average across application methods) by 10-times over control (62.52 g N ha-1). However, emissions were not significantly (P > 0.05) different among the treatments. Fertilizer induced emission factors (EFs) were not affected by N placement methods in either rice or wheat. On average, EFs in the rice were very low (<0.002%) compared to the wheat (0.5%). This study reveals that (regardless of treatments), the contribution of rice (<4 g N ha-1) on total annual NO emissions (433 g N ha-1) was very small (<0.5%) compared to emissions from wheat.


Assuntos
Poluentes Atmosféricos/análise , Produção Agrícola/métodos , Fertilizantes/análise , Óxido Nítrico/análise , Oryza/crescimento & desenvolvimento , Triticum/crescimento & desenvolvimento , Nitrogênio/análise , Ureia/análise
18.
Environ Sci Pollut Res Int ; 26(18): 18291-18303, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31041699

RESUMO

Combustion engines bring a lot of pollution products to human living environment. This study introduced a green engine called free-piston linear engine (FPLE), and performed an evaluation on the pollutant emissions of a diesel FPLE by comparison with a corresponding conventional crankshaft engine (CCE). The combustion reaction and pollutant formation were described by a comprehensive model which considers the special operation mechanism of the FPLE. The effect of dynamic and fuel quantity on the unclean combustion products of the FPLE and the CCE was compared. Results indicate that in the case of the fuel quantity of 7.1 mg condition, the pollutant forming in the FPLE is generally later than that in CCE because of the higher speed of FPLE around the reverse point of stroke, and a significant advantage in nitric oxide (NO) emission is found for the FPLE, although it emits more carbon monoxide (CO) and soot. Moreover, compared with the CCE, the FPLE is cleaner in lean fuel conditions because the NO production of the FPLE is only half of that of the CCE, and that of other pollutants is almost at the same level. However, in heavy fuel conditions, the FPLE shows a disadvantage in CO and soot emission due to the serious afterburning effect and poor oxygen environment in some local areas, although its NO production is still lower than that of the CCE.


Assuntos
Poluentes Ambientais/análise , Emissões de Veículos/análise , Poluentes Atmosféricos/análise , Monóxido de Carbono/análise , Poluentes Ambientais/química , Gasolina , Humanos , Óxido Nítrico/análise , Oxigênio , Fuligem/análise
19.
Molecules ; 24(10)2019 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-31109021

RESUMO

A new luminescent Tb-DOTAGA (1,4,7,10-tetraazacyclododecane-1-glutaric-4,7,10- triacetic acid) complex (TbL) was synthesized and covalently immobilized on a silicon wafer. The grafting process was monitored by means of IR and XPS spectroscopies and the optical properties of the functionalized silicon wafer (TbL@Si) were investigated by fluorescence experiments. A homemade setup was then implemented in order to follow TbL@Si optical properties in the presence of gaseous nitric oxide (NO). The prima facie results indicated that in the presence of NO, the wafer fluorescence was partially quenched. This quenching was reversible as soon as NO was pumped outside the fluorescence cell, which could be interesting for the further development of lanthanide labelled silicon wafers as gas phase sensors.


Assuntos
Complexos de Coordenação/síntese química , Óxido Nítrico/análise , Complexos de Coordenação/química , Ligantes , Luminescência , Estrutura Molecular , Silício/química
20.
J Environ Sci (China) ; 81: 195-204, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30975322

RESUMO

CuFe-SSZ-13 catalyst showed excellent performance in the selective catalytic reduction of NOx with NH3 (NH3-SCR) for diesel engine exhaust purification. To investigate the effect of preparation methods on NH3-SCR performance, Fe was loaded into one-pot synthesized Cu-SSZ-13 catalysts through solid-state ion-exchange (SSIE), homogeneous deposition precipitation (HDP) and liquid ion-exchange (IE), respectively. Three CuFe-SSZ-13 catalysts showed similar SO2 resistance, which was better than that of Cu-SSZ-13. The improvement was attributed to the protection of Fe species. Hydrothermal stability of three CuFe-SSZ-13 catalysts was significantly different, which was attributed to the state of active species caused by different preparation methods. Compared with the other two catalysts, more active species existed inside the zeolite pores of CuFe-SSZ-13SSIE. During hydrothermal aging, the aggregation of these active species in the pores caused the collapse of catalyst structure, ultimately leading to the deactivation of CuFe-SSZ-13SSIE. In contrast, Fe species was dispersed better on the surface over CuFe-SSZ-13IE, enhancing the hydrothermal stability of catalysts. Consequently, Fe loading effectively improved the resistance of SO2 and H2O over Cu-SSZ-13. For CuFe-SSZ-13, large amounts of active species located inside the zeolite pores are not beneficial for the hydrothermal stability.


Assuntos
Poluentes Atmosféricos/análise , Amônia/análise , Modelos Químicos , Óxido Nítrico/análise , Poluentes Atmosféricos/química , Amônia/química , Catálise , Troca Iônica , Óxido Nítrico/química , Oxirredução , Zeolitas/química
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