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1.
Biomed Pharmacother ; 127: 110142, 2020 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-32330795

RESUMO

Atopic dermatitis (AD) is a common relapsing inflammatory skin disease characterized by severe pruritus that seriously affects the quality of patients' life. There is an increasingly large amount of research demonstrating that traditional Chinese medicine (TCM) including herbal formulae and bioactive ingredients exerts pharmacological effects on atopic dermatitis. It has been a long history of TCM being used to treat atopic dermatitis, especially in preventing disease recurrence, maintaining long-term remission, and reducing disease burden. Nowadays, both of TCM monomer preparations and traditional formulae are still widely used. This review focuses on TCM as well as its bioactive ingredients for the treatment of AD, from the perspectives of animal model construction, pharmacodynamic mechanisms and clinical studies of formulae. To be more specific, the regulation and molecular mechanisms of the herbal formulae and bioactive ingredients of TCM are investigated, and the latest clinical research on TCM formulae is discussed. Furthermore, it provides a summary of the strengths and utilities of TCM, and will be useful for doctors who use Chinese medicine for treatment or researchers who select candidates for clinical treatments or further high-quality clinical studies.

2.
Curr Med Sci ; 40(1): 138-144, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32166676

RESUMO

This study examined anti-cancer compounds present in the chloroform extract of the Chinese medicine formula Shenqi San (CE-SS). Silica gel column chromatography, Sephadex LH-20, octadecylsilyl (ODS) column chromatography, and high performance liquid chromatography (HPLC) were used to separate the compounds from CE-SS. The structural formulas of the separated compounds were determined using 1D 1H and 13C experiments as well as high resolution electrospray ionization mass spectroscopy (HRESIMS). The corresponding results were compared with the reported literature data. A total of six compounds were separated and their structures were identified on the basis of corresponding spectroscopic and physico-chemical properties. They were Saikogenin F (I), Prosaikogenin D (II), Prosaikogenin F (III), ß-sitosterol (IV), 3ß,16ß,23-trihydroxy-13,28-epoxyurs-11-ene-3-O-ß-D-glucopyranoside (V), and methyl ursolic acid (VI). The separated compounds were evaluated in vitro for their inhibitory ability against the proliferation of A549 cells via MTT assay. Apoptosis was investigated using Annexin V-FITC/propidium iodide (PI) by flow cytometry. Apoptosis-associated proteins were examined by Western blotting. All the compounds were observed to have inhibitory activities against the proliferation of A549 cells to different degrees. Flow cytometry showed that compound V increased the proportion of apoptotic A549 cells in a dose-dependent manner. Western blotting showed that compound V increased the expression of Bax, cleaved-caspase-3, cleaved-caspase-9 and cleaved-poly ADP-ribose polymerase (PARP), and decreased the expression of Bcl-2. These results indicated that compound V featured a significant inhibitory effect on A549 cells when compared with other compounds, and it may be considered a potential drug against cancers.

3.
Mol Med Rep ; 20(5): 4645-4653, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31545496

RESUMO

Previous studies have demonstrated that microRNA (miR)­146a is involved in the inflammatory response of atopic dermatitis (AD). The aim of the present study was to investigate the expression of miR­146a in the serum of patients with AD and in skin lesions of AD animal models. In addition, we aimed to predict and verify the target genes of miR­146a. miR­146a expression was measured in AD patient serum via reverse transcription­quantitative PCR. T­helper (Th)1 [CD4+; interferon (IFN)­Î³+] and Th2 [CD4+; interleukin (IL)­4+] expression in peripheral blood mononuclear cells was evaluated using flow cytometry. Following the establishment of a 2,4­dinitrofluorobenzene­induced C57BL/6 mouse AD model, Th1 (CD4+IFN­Î³+) and Th2 (CD4+IL­4+) expression was analyzed in murine spleen cells via flow cytometry. Plasmids were transfected into 293T cells and at 48 h post­transfection, cells were analyzed using a luciferase assay system. The results revealed that the AD group had a significantly lower Th1/Th2 ratio and a significantly higher miR­146a expression compared with the control group (P<0.05). Furthermore, a decreased Th1/Th2 ratio and a significantly increased miR­146a expression were observed in the model group compared with the control group (P<0.01). We also conducted a dual­luciferase assay to determine whether small ubiquitin­related modifier 1 (SUMO1) if the target gene of miR­146a. We observed a ~30% decrease in the relative luciferase activity in cells containing the 3'­untranslated region of SUMO1 + miR­146a). The results of the luciferase assay indicated that may be a direct mRNA target of miR­146a; however, the quantification of band density of SUMO1 expression following western blotting did not significantly differ. The development of animal models in AD research is of vital importance. The results revealed that miR­146a may be a potential regulator involved in the pathogenesis of AD. Furthermore, the current study determined that miR­146a could be a valuable marker of AD and thus, may be applied in the development of therapeutic strategies for treating AD.


Assuntos
Biomarcadores , Dermatite Atópica/etiologia , Regulação da Expressão Gênica , MicroRNAs/genética , Regiões 3' não Traduzidas , Adolescente , Adulto , Animais , Estudos de Casos e Controles , Criança , Pré-Escolar , Dermatite Atópica/metabolismo , Modelos Animais de Doenças , Suscetibilidade a Doenças , Feminino , Humanos , Leucócitos Mononucleares/metabolismo , Masculino , Camundongos , Interferência de RNA , Proteína SUMO-1/genética , Proteína SUMO-1/metabolismo , Baço/imunologia , Baço/metabolismo , Linfócitos T Auxiliares-Indutores/imunologia , Linfócitos T Auxiliares-Indutores/metabolismo , Adulto Jovem
4.
Iran J Allergy Asthma Immunol ; 18(4): 347-357, 2019 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-31522443

RESUMO

Atopic dermatitis (AD) is a chronic, recurrent skin condition resulting from both genetic and environmental factors. In recent decades, the prevalence of AD has increased considerably in some countries. However, given that the role of genetics is unlikely to have changed over this short period, the increased prevalence is more likely to be explained by changes in environmental and maternal factors. The aim of this review is to comprehensively summarize the various factors impacting AD incidence in offspring and provide guidance for primary prevention. Recent research has demonstrated that environmental and climate factors, maternal history of allergies, gestational diabetes, and stress play essential roles in increasing the risk of AD in infants. Some factors have protective effects against the incidence of AD, including probiotic supplementation, fish intake, and moisturizers. This review also considers fundamental research into AD prevalence and factors that in the past were mistakenly thought to affect that prevalence, such as caesarean section and antigen avoidance. The potential influence of these factors on infant AD incidence remains inconclusive and needs further study. Furthermore, infants with a family history of atopic disease may benefit from early weaning or reduced breastfeeding duration.


Assuntos
Dermatite Atópica/epidemiologia , Dermatite Atópica/etiologia , Suscetibilidade a Doenças , Exposição Materna , Efeitos Tardios da Exposição Pré-Natal , Dieta , Meio Ambiente , Feminino , Humanos , Hipótese da Higiene , Incidência , Nutrientes , Gravidez , Probióticos , Fatores de Risco
5.
Artigo em Inglês | MEDLINE | ID: mdl-31425021

RESUMO

Low-dose CT image reconstruction has been a popular research topic in recent years. A typical reconstruction method based on post-log measurements is called penalized weighted-least squares (PWLS). Due to the underlying limitations of the post-log statistical model, the PWLS reconstruction quality is often degraded in low-dose scans. This paper investigates a shifted-Poisson (SP) model based likelihood function that uses the pre-log raw measurements that better represents the measurement statistics, together with a data-driven regularizer exploiting a Union of Learned TRAnsforms (SPULTRA). Both the SP induced data-fidelity term and the regularizer in the proposed framework are nonconvex. The proposed SPULTRA algorithm uses quadratic surrogate functions for the SP induced data-fidelity term. Each iteration involves a quadratic subproblem for updating the image, and a sparse coding and clustering subproblem that has a closed-form solution. The SPULTRA algorithm has a similar computational cost per iteration as its recent counterpart PWLS-ULTRA that uses post-log measurements, and it provides better image reconstruction quality than PWLS-ULTRA, especially in low-dose scans.

6.
Environ Pollut ; 253: 377-383, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31325882

RESUMO

Changzhou, an industrial city in the Yangtze River Delta, has been experiencing serious haze pollution, particularly in winter. However, studies pertaining to the haze in Changzhou are very limited, which makes it difficult to understand the characteristics and formation of winter haze in this area, and develop effective control measures. In this study, we carried out continuous online observation of particulate matter, chemical components, and meteorology in Changzhou in February 2017. Our results showed that haze pollution occurred frequently in Changzhou winter and exhibited two patterns: dry haze with low relative humidity (RH) and wet haze with high RH. Water-soluble inorganic ions (SO42-, NO3-, and NH4+) accounted for ∼52.2% of the PM2.5 mass, of which sulfate was dominant in wet haze periods while nitrate was dominant in other periods. With the deterioration of haze pollution, the proportion of nitrate in PM2.5 increased, while sulfate proportion increased under wet haze and decreased under dry haze. Dry haze and wet haze appeared under slow north wind and south wind, respectively, and strong north wind or sea breeze scavenged pollution. We found that formation of nitrate occurred rapidly in daytime with high concentrations of odd oxygen (Ox = O3 + NO2), whereas formation of sulfate occurred rapidly during nighttime with high RH, indicating that photochemistry and heterogeneous reaction were the major formation mechanisms for nitrate and sulfate, respectively. Through the cluster analysis of 36-h backward trajectories, five sources of air masses from three directions were identified. High PM2.5 concentrations (84.1 µg m-3 on average) usually occurred under the influence of two clusters (46%) from the northwest, indicating that regional transport from northern China aggravated the winter haze pollution in Changzhou. Emission reduction, particularly the mobile sources, and regional joint prevention and control can help to mitigate the winter haze in Changzhou.


Assuntos
Poluentes Atmosféricos/análise , Monitoramento Ambiental , Material Particulado/análise , Aerossóis/análise , China , Cidades , Umidade , Meteorologia , Nitratos/análise , Óxidos de Nitrogênio/análise , Rios , Estações do Ano , Sulfatos/análise , Vento
7.
J Environ Sci (China) ; 83: 8-20, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31221390

RESUMO

With rapid economic growth and urbanization, the Yangtze River Delta (YRD) region in China has experienced serious air pollution challenges. In this study, we analyzed the air pollution characteristics and their relationship with emissions and meteorology in the YRD region during 2014-2016. In recent years, the concentrations of all air pollutants, except O3, decreased. Spatially, the PM2.5, PM10, SO2, and CO concentrations were higher in the northern YRD region, and NO2 and O3 were higher in the central YRD region. Based on the number of non-attainment days (i.e., days with air quality index greater than 100), PM2.5 was the largest contributor to air pollution in the YRD region, followed by O3, PM10, and NO2. However, particulate matter pollution has declined gradually, while O3 pollution worsened. Meteorological conditions mainly influenced day-to-day variations in pollutant concentrations. PM2.5 concentration was inversely related to wind speed, while O3 concentration was positively correlated with temperature and negatively correlated with relative humidity. The air quality improvement in recent years was mainly attributed to emission reductions. During 2014-2016, PM2.5, PM10, SO2, NOx, CO, NH3, and volatile organic compound (VOC) emissions in the YRD region were reduced by 26.3%, 29.2%, 32.4%, 8.1%, 15.9%, 4.5%, and 0.3%, respectively. Regional transport also contributed to the air pollution. During regional haze periods, pollutants from North China and East China aggravated the pollution in the YRD region. Our findings suggest that emission reduction and regional joint prevention and control helped to improve the air quality in the YRD region.


Assuntos
Poluentes Atmosféricos/análise , Poluição do Ar/estatística & dados numéricos , Monitoramento Ambiental , Conceitos Meteorológicos , China , Meteorologia , Ozônio , Material Particulado/análise , Rios , Estações do Ano , Temperatura , Urbanização
8.
Anal Cell Pathol (Amst) ; 2019: 7697610, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31183317

RESUMO

TEEG (3ß,16ß,23-trihydroxy-13,28-epoxyurs-11-ene-3-O-ß-D-glucopyranoside) is derived from the chloroform extract of the Chinese medicine formula Shenqi San (CE-SS). In the present study, we aimed to elucidate the anticancer effect and possible molecular mechanism underlying the action of TEEG against the human non-small cell lung cancer (NSCLC) cell line A549 in vitro. A549 cells were incubated with different concentrations of TEEG. Cell proliferation was assessed by MTT assay. Autophagy was evaluated by immunofluorescence staining. Autophagy-associated proteins were examined by Western blot analysis. TEEG markedly inhibited A549 cell proliferation in a concentration-dependent manner. Immunofluorescence staining showed that TEEG induced autophagy in A549 cells. The LC3-II : LC3-I conversion ratio and the expression of Beclin-1, Atg5, Atg7, and Atg12 increased with the concentration of TEEG. In addition, increased TEEG concentration enhanced the expression of Class III p-PI3K and reduced the expression of Class I p-PI3K, p-AKT, p-mTOR, and p-P70S6K. These results indicate that TEEG induces autophagy of A549 cells through regulation of the PI3K/AKT/mTOR signaling pathway.


Assuntos
Autofagia/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Medicamentos de Ervas Chinesas/farmacologia , Glucosídeos/farmacologia , Transdução de Sinais/efeitos dos fármacos , Células A549/efeitos dos fármacos , Antineoplásicos/química , Antineoplásicos/farmacologia , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Glucosídeos/química , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Serina-Treonina Quinases TOR/metabolismo
9.
Environ Int ; 126: 552-559, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30852442

RESUMO

Numerous epidemiologic studies on adverse health effects of air pollution have been well documented; however, assessment on health benefits of air quality improvement from air pollution control measures has been limited in developing countries. We assessed the mortality benefits associated with air pollution improvement over 11 years in Guangzhou, China (2006-2016). A time series analysis with Generalized additive Poisson models was used to estimate mortality effects of ozone (O3) and nitrogen dioxide (NO2), adjusting for time trend, day of week, public holiday, temperature and relative humidity. We further estimated the changes in mortality burden of O3 and NO2, including attributable fraction (AF, in %) and attributable mortality (AM, in number of death) during study period. We lastly estimated mortality effects during the 2010 Asian Games (November 12 to December 18, 2010) compared to a baseline period consisting of 4-week before and 4-week after the game. During the study period, average annual concentrations of NO2 decreased from 42.3 µg/m3 in 2006 to 33.8 µg/m3 in 2016; while O3 levels remained stable over time. We observed significant increases in mortality of O3 and NO2, with approximately linear exposure-response relationships. In specific, each increase of 10 µg/m3 in O3 and NO2 at 2 prior days was associated with increases of 0.60% (95% confidence interval (CI): 0.47, 0.74) and 1.89% (95%CI: 1.49, 2.29) in total mortality, respectively. We further estimated that AF on total mortality attributed to NO2 decreased from 1.38% (95%CI: 1.09, 1.68) in 2006-2010 to 0.43% (95%CI: 0.34, 0.52) in 2011-2016, corresponding to AM on total mortality of 2496 deaths (95%CI: 1964, 3033) to 1073 deaths (95%CI: 846, 1301). During the 2010 Asian Games, we observed decrease in total mortality of 9.3% (95%CI: -15.0, -3.2) in comparison with that observed in the baseline period. Similar mortality benefits in cardiovascular diseases were also observed. Our results showed reduced mortality burden from air pollution improvement in Guangzhou in recent years, which provide strong rationale for continuing to reduce air pollution through comprehensive and rigorous air quality management in the area.


Assuntos
Poluentes Atmosféricos/análise , Poluição do Ar/análise , Mortalidade/tendências , Dióxido de Nitrogênio/análise , Ozônio/análise , Doenças Cardiovasculares/mortalidade , China , Humanos , Material Particulado/análise
10.
Environ Pollut ; 244: 84-92, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30326389

RESUMO

Organic aerosol (OA) are always the most abundant species in terms of relative proportion to PM2.5 concentration in Beijing, while in previous studies, poor link between carbonaceous particles and their gaseous precursors were established based on field observation results. Through this study, we provided a comprehensive analysis of critical carbonaceous species in the atmosphere. The concentrations, diurnal variations, conversions, and gas-particle partitioning (F-factor) of 8 carbonaceous species, carbon dioxide (CO2), carbon monoxide (CO), methane (CH4), volatile organic compounds (VOCs), non-methane hydrocarbon (NMHC), organic carbon (OC), elemental carbon (EC), and water soluble organic compounds (WSOCs), in Beijing were analyzed synthetically. Carbonaceous gases (CO, CO2, VOCs, and CH4) and OC/EC ratios exhibited double-peak diurnal patterns with a pronounced midnight peak, especially in winter. High correlation between VOCs and OC during winter nighttime indicated that OC was formed from VOCs precursors via an unknown mechanism at relative humidity greater than 50% and 80%, thereby promoting WSOC formation in PM1 and PM2.5 respectively. The established F-factor method was effective to describe gas-to-particle transformation of carbonaceous species and was a good indicator for haze events since high F-factors corresponded with enhanced PM2.5 level. Moreover, higher F-factors in winter indicated carbonaceous species were more likely to exist as particles in Beijing. These results can help gain a comprehensive understanding of carbon cycle and formation of secondary organic aerosols from gaseous precursors in the atmosphere.


Assuntos
Poluentes Atmosféricos/análise , Carbono/análise , Monitoramento Ambiental/métodos , Umidade , Compostos Orgânicos/análise , Material Particulado/análise , Estações do Ano , Aerossóis/análise , Poluição do Ar , Atmosfera/análise , Pequim , Ciclo do Carbono , Dióxido de Carbono/análise , Monóxido de Carbono/análise , China , Metano/análise , Tamanho da Partícula , Compostos Orgânicos Voláteis/análise , Água/análise
11.
Environ Pollut ; 242(Pt A): 544-554, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30007265

RESUMO

Continuous haze monitoring was conducted from 12:00 3 April to 12:00 8 April 2016 in Beijing, China to develop a more detailed understanding of spring haze characteristics. The PM2.5 concentration ranged from 6.30 to 165 µg m-3 with an average of 63.8 µg m-3. Nitrate was the most abundant species, accounting for 36.4% of PM2.5, followed by organic carbon (21.5%), NH4+ (19.3%), SO42- (18.8%), and elemental carbon (4.10%), indicating the key role of nitrate in this haze event. Species contribution varied based on the phase of the haze event. For example, sulfate concentration was high during the haze formation phase, nitrate was high during the haze, and secondary organic carbon (SOC) had the highest contribution during the scavenging phase. The secondary transition of sulfate was influenced by SO2, followed by relative humidity (RH) and Ox (O3+NO2). Nitrate formation occurred in two stages: through NO2 oxidation, which was vulnerable to Ox; and by the partitioning of N (+5) which was susceptible to RH and temperature. SOC tended to form when Ox and RH were balanced. According to hourly species behavior, sulfate and nitrate were enriched during haze formation when the mixed layer height decreased. However, SOC accumulated prior to the haze event and during formation, which demonstrated the strong contribution of secondary inorganic aerosols, and the limiting contribution of SOC to this haze case. Investigating backward trajectories showed that high speed northwestern air masses following a straight path corresponded to the clear periods, while southwesterly air masses which traversed heavily polluted regions brought abundant pollutants to Beijing and stimulated the occurrence of haze pollution. Results indicate that the control of NO2 needs to be addressed to reduce spring haze. Finally, the correlation between air mass trajectories and pollution conditions in Beijing reinforce the necessity of inter-regional cooperation and control.


Assuntos
Poluentes Atmosféricos/análise , Monitoramento Ambiental , Material Particulado/análise , Aerossóis/análise , Poluição do Ar/análise , Poluição do Ar/estatística & dados numéricos , Pequim , Carbono , China , Nitratos/análise , Estações do Ano , Sulfatos/análise , Transportes
12.
Mol Med Rep ; 16(5): 7175-7184, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28944829

RESUMO

The thymus is critical in establishing and maintaining the appropriate microenvironment for promoting the development and selection of T cells. The function and structure of the thymus gland has been extensively studied, particularly as the thymus serves an important physiological role in the lymphatic system. Numerous studies have investigated the morphological features of thymic involution. Recently, research attention has increasingly been focused on thymic proteins as targets for drug intervention. Omics approaches have yielded novel insights into the thymus and possible drug targets. The present review addresses the signaling and transcriptional functions of the thymus, including the molecular mechanisms underlying the regulatory functions of T cells and their role in the immune system. In addition, the levels of cytokines secreted in the thymus have a significant effect on thymic functions, including thymocyte migration and development, thymic atrophy and thymic recovery. Furthermore, the regulation and molecular mechanisms of stress­mediated thymic atrophy and involution were investigated, with particular emphasis on thymic function as a potential target for drug development and discovery using proteomics.


Assuntos
Citocinas/metabolismo , Transdução de Sinais , Linfócitos T/metabolismo , Timo/metabolismo , Animais , Movimento Celular , Humanos , Fosfatidilinositol 3-Quinase/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Linfócitos T/citologia , Linfócitos T/imunologia , Linfócitos T Reguladores/citologia , Linfócitos T Reguladores/metabolismo , Serina-Treonina Quinases TOR/metabolismo , Timo/citologia
13.
Environ Pollut ; 229: 339-349, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28609735

RESUMO

Heavy haze pollution occurs frequently in northern China, most critically in the Beijing-Tianjin-Hebei area (BTH). Zibo, an industrial city located in Shandong province, is often listed as one of the top ten most polluted cities in China, particularly in winter. However, no studies of haze in Zibo have been conducted, which limits the understanding of the source and formation of haze pollution in this area, as well as mutual effects with the BTH area. We carried out online and continuous integrated field observation of particulate matter in winter, from 11 to 25 January 2015. SO42-, NO3-, and NH4+ (SIA) and organics were the main constituents of PM2.5, contributing 59.4% and 33.6%, respectively. With the increasing severity of pollution, the contribution of SIA increased while that of organics decreased. Meteorological conditions play an important role in haze formation; high relative humidity (RH) and low wind speed increased both the accumulation of pollutants and the secondary transition from gas precursors (gas-particle phase partitioning). Since RH and the presence of O3 can indicate heterogeneous and photochemistry processes, respectively, we carried out correlation analysis and linear regression to identify their relative importance to the three main secondary species (sulfate, nitrate, and secondary organic carbon (SOC)). We found that the impact of RH is in the order of SO42- > NO3- > SOC, while the impact of O3 is reversed, in the order of SOC > NO3- > SO42-, indicating different effect of these factors on the secondary formation of main species in winter. Cluster analysis of backward trajectories showed that, during the observation period, six directional sources of air masses were identified, and more than 90% came from highly industrialized areas, indicating that regional transport from industrialized areas aggravates the haze pollution in Zibo. Inter-regional joint prevention and control is necessary to prevent further deterioration of the air quality.


Assuntos
Poluentes Atmosféricos/análise , Poluição do Ar/estatística & dados numéricos , Monitoramento Ambiental , Material Particulado/análise , Aerossóis/análise , Poluição do Ar/análise , Pequim , China , Cidades , Poluição Ambiental , Umidade , Meteorologia , Nitratos/análise , Estações do Ano , Sulfatos/análise , Vento
14.
Environ Pollut ; 227: 296-305, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28477554

RESUMO

Four haze episodes (EPs) were observed in October 2014 in Beijing, China. For better understanding of the characteristics and the formation mechanisms of PM2.5 (particulate matter with an aerodynamic diameter ≤ 2.5 µm), especially secondary water-soluble inorganic species in these haze events, hourly concentrations of PM2.5, sulfate, nitrate, and ammonium (SNA) were measured in this study. Concentrations of gaseous pollutants and meteorological parameters were also measured. The average concentration of PM2.5 was 106.6 ± 83.5 µg m-3, which accounted for around 53% of PM10 (particulate matter with an aerodynamic diameter ≤ 10 µm) mass. Nitrogen dioxide (NO2) concentration was much higher than that of sulfur dioxide (SO2) since October is a non-heating month. SNA is the most abundant secondary water-soluble inorganic species and contributed to 33% of PM2.5 mass concentration. Sulfur oxidation ratio (SOR) was much higher than nitrogen oxidation ratio (NOR). NOR and SOR increased with elevated PM2.5 levels and heterogeneous processes seemed to be the most plausible explanation of this increase. Relative humidity (RH), which is of great influence on aerosol liquid water content (ALWC), played a considerable role in the formation of secondary inorganic aerosols, accelerated the secondary transformation of gaseous precursors, and further aggravated haze pollution. The positive feedback loop associated with high aerosol levels and low planetary boundary layer (PBL) height led to the evolution and exacerbation of heavy haze pollution. Fire maps and 48-h air mass backward trajectories supported the significant impact of biomass burning activities and regional transport on haze formation over Beijing in October 2014.


Assuntos
Poluentes Atmosféricos/análise , Monitoramento Ambiental , Material Particulado/análise , Aerossóis/análise , Pequim , China , Meteorologia , Nitratos/análise , Dióxido de Nitrogênio , Estações do Ano , Solubilidade , Sulfatos/análise , Dióxido de Enxofre , Água
15.
Sci Total Environ ; 574: 1559-1570, 2017 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-27613675

RESUMO

Daily PM2.5 samples were collected at an urban site in Guangzhou in 2014 and at a suburban site in Zhuhai in 2014-2015. Samples were subject to chemical analysis for various chemical components including organic carbon (OC), element carbon (EC), major water-soluble inorganic ions, and trace elements. The annual average PM2.5 mass concentration was 48±22µgm-3and 45±25µgm-3 in Guangzhou and Zhuhai, respectively, with the highest seasonal average concentration in winter and the lowest in summer at both sites. Regional transport of pollutants accompanied with different air mass origins arriving at the two sites and pollution sources in between the two cities caused larger seasonal variations in Zhuhai (>a factor of 3.5) than in Guangzhou (17% of PM2.5 mass concentrations.

16.
Sci Total Environ ; 573: 1-10, 2016 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-27543686

RESUMO

Ship emissions contribute significantly to air pollution and impose health risks to residents along the coastal area. By using the refined data from the Automatic Identification System (AIS), this study developed a highly resolved ship emission inventory for the Pearl River Delta (PRD) region, China, home to three of ten busiest ports in the world. The region-wide SO2, NOX, CO, PM10, PM2.5, and VOC emissions in 2013 were estimated to be 61,484, 103,717, 10,599, 7155, 6605, and 4195t, respectively. Ocean going vessels were the largest contributors of the total emissions, followed by coastal vessels and river vessels. In terms of ship type, container ship was the leading contributor, followed by conventional cargo ship, dry bulk carrier, fishing ship, and oil tanker. These five ship types accounted for >90% of total emissions. The spatial distributions of emissions revealed that the key emission hot spots all concentrated within the newly proposed emission control area (ECA) and ship emissions within ECA covered >80% of total ship emissions in the PRD, highlighting the importance of ECA in emissions reduction in the PRD. The uncertainties of emission estimates of pollutants were quantified, with lower bounds of -24.5% to -21.2% and upper bounds of 28.6% to 33.3% at 95% confidence intervals. The lower uncertainties in this study highlighted the powerfulness of AIS data in improving ship emission estimates. The AIS-based bottom-up methodology can be used for developing and upgrading ship emission inventory and formulating effective control measures on ship emissions in other port regions wherever possible.


Assuntos
Poluentes Atmosféricos/análise , Monitoramento Ambiental/métodos , Material Particulado/análise , Rios , Navios , Emissões de Veículos/análise , China , Tamanho da Partícula
17.
Huan Jing Ke Xue ; 36(4): 1217-26, 2015 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-26164893

RESUMO

To analyze the characteristic of marine emission in Shenzhen City, activity-based and fuel-based approaches were utilized to develop the marine emission inventory for the year of 2010, using the vessel files from the Lloyd's register of shipping (LR) and vessel track data from the automatic identification system (AIS). The marine emission inventory was temporally (resolution: 1 hour) and spatially (resolution: 1 km x 1 km) allocated based on the vessel track data. Results showed that total emissions of SO2, NO(x), CO, PM10, PM2.5 and VOCs from marine vessels in Shenzhen City were about 13.6 x 10(3), 23.3 x 10(3), 2.2 x 10(3), 1.9 x 10(3), 1.7 x 10(3) and 1. x 10(3) t, respectively. Among various types of marine vessels, emission from container vessels was the highest; for different driving modes, hotelling mode was found with the largest mission. Marine emissions were generally higher in the daytime, with vessel-specific peaks. For spatial distributions, in general, marine emissions were zonally distributed with hot spots in the western port group, Dapeng Bay and the key waterway.


Assuntos
Monitoramento Ambiental , Navios , Emissões de Veículos , China , Cidades
18.
Sci Rep ; 5: 8234, 2015 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-25648768

RESUMO

Jagged-1 signaling has recently been reported to be involved in the Th17 cell differentiation. However, little is known about its mechanisms. Soluble Jagged-1 was used to activate the Jagged-1-Notch signaling to interfere with the IL-6 and TGF-ß-induced Th17 cell skewing. Genes relevant to the autoimmunity or inflammation were screened for the first time in this system by qPCR array for the differential expressions. The 18 genes out of 84, including Clec7a, Il12b, Il12rb1, Il12rb2, Csf3, Il15, Il17a, Il17f, Il17rc, Il17rd, Il17re, Il23a, Myd88, Socs1, Stat4, Stat5a, Sykb and Tbx21, were downregulated, but only Cxcl2, Cxcl12 and Mmp3 were upregulated. The expressions of the genes, Rorγt, Il17a, Il17f, Il12rb1 and Il23a, induced by simultaneous IL-6 and TGF-ß treatment were significantly suppressed by Jagged-1, followed by the reduction of RORγt, IL-17A, and IL-17F. Consistent with the attenuation of RORγt, and the reduced production and secretion of IL-17A and IL-17F in the cell supernatant and the in situ stained cells, the number of CD4(+)IL-17(+) cells was also diminished. It is concluded that the Jagged-1-Notch signaling can suppress the IL-6 and TGF-ß treatment-induced Th17 cell skewing through the attenuation of RORγt and, hence by, the down-regulation of IL-17A, IL-17F, IL-23a, and IL-12rb1.


Assuntos
Proteínas de Ligação ao Cálcio/metabolismo , Citocinas/metabolismo , Citocinas/farmacologia , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Proteínas de Membrana/metabolismo , Membro 3 do Grupo F da Subfamília 1 de Receptores Nucleares/metabolismo , Transdução de Sinais , Células Th17/efeitos dos fármacos , Células Th17/metabolismo , Animais , Diferenciação Celular/efeitos dos fármacos , Diferenciação Celular/genética , Regulação da Expressão Gênica , Interleucina-17/metabolismo , Interleucina-17/farmacologia , Interleucina-6/farmacologia , Proteína Jagged-1 , Camundongos , Receptores Notch/metabolismo , Proteínas Serrate-Jagged , Subpopulações de Linfócitos T/citologia , Subpopulações de Linfócitos T/efeitos dos fármacos , Subpopulações de Linfócitos T/metabolismo , Células Th17/citologia
19.
Ann Med ; 45(8): 532-8, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24195599

RESUMO

AIM: This study's purpose was to determine if there was a relationship between Nobel Laureates' awards and landmark papers and winning the Nobel Prize in Physiology or Medicine during 1983-2012. METHODS: The 66 Nobelists' awards and landmark papers in the period 1983-2012 were analyzed. RESULTS: The results showed that the most Nobelists had won Gairdner, Lasker, Howitz or Wolf Award before they won Nobel Prize, indicating that Gairdner Award may be considered as a Nobel Prize's wind vane. A small number of landmark papers were indeed published in low impact factor journals (10.5% below impact factor 5.0) and some of their citation were low (23.2% below 400 times). There were 61 of 76 landmark papers published in the journals of JCR partition 1, reaching 80%, but 2 of 76 landmark papers were even outside of JCR partition, demonstrating that JCR partition acts as a reciprocal supplement with impact factor and citation times. The test period of Nobel Prize was substantially between 10 to 30 years. There were 5 persons whose landmark papers were cited all above 6000 times to get Nobel Prize within the test period of ten years, suggesting that there is a trend of certain inverse ratio between the citation and the test period of Nobel Prize. CONCLUSION: These findings provide a new insight into the relationship among Nobel Laureates' awards, landmark papers and Nobel Prize in Physiology or Medicine.


Assuntos
Bibliometria , Prêmio Nobel , Publicações Periódicas como Assunto/estatística & dados numéricos , Fisiologia , Distinções e Prêmios , Humanos , Fator de Impacto de Revistas
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