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1.
Sci Total Environ ; 904: 166748, 2023 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-37659525

RESUMEN

In this study, a revised CMAQ model incorporating source and temporal apportioning functions has been used to analyze the aging characteristics of SOA in East Asia. The results show that in the aerosol phase, the fraction of the non-volatile components typically fluctuates around 75 %-95 %, and aromatic hydrocarbon precursors contribute significantly to SOA, accounting for 45.6 %-72.7 % in winter and 29.1 %-52.7 % in summer. Transport due to meteorological conditions does not affect the SOA volatility profile in the cities, while regional source composition has been found to be important for the characterization of the properties of SOA in cities. When the SOA regional composition type is a multi-region-imported-dominated type (MRT), its age composition type tends to be an old-age-SOA-dominated type (OAT) (>48 h). Additionally, transport also causes fluctuations in the range of hourly SOA with atmospheric age of 96 h or higher. The SOAs normally transport through seasonal monsoon and could migrate longer in winter (700-1500 km in January) than in other seasons (250-900 km in April; 500-1200 km in July; 300-1000 km in October). Additionally, in winter, non-volatile SOA generally has a longer transport distance (700-1600 km) than semi- and low-volatile SOA (300-1300 km and 600-1500 km). Furthermore, during the transport process, geographical barriers have negligible impact on SOA in the 48+ hour age group.

2.
Front Pharmacol ; 14: 1149665, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37346294

RESUMEN

Rheumatoid arthritis (RA) has a high prevalence in patients with non-alcoholic fatty liver disease (NAFLD); however, the underlying mechanism is unclear. To address this, our study established a rat model with both NAFLD and RA by feeding a high-fat diet (HFD) and administering intradermal injection of Freund's complete adjuvant (FCA) with bovine type II collagen. Collagen-induced RA (CIA) was confirmed by hind paw swelling and histological examination. The histomorphological characteristics of NAFLD were evaluated by Masson's trichrome and hematoxylin-eosin staining. The development of NAFLD was further evaluated by measuring serum concentrations of triglyceride (TG), total cholesterol (T-CHO), alanine aminotransferase (ALT), aspartate aminotransferase (AST), and lipopolysaccharide (LPS). The results showed that HFD feeding exacerbated secondary inflammation in CIA rats, whereas FCA/bovine type II collagen injection increased serum levels of ALT, AST, TG, T-CHO, and LPS and exacerbated hepatic fibrosis in both normal and NAFLD rats. Interestingly, NAFLD + CIA significantly promoted the expression of PTRF, a caveolae structure protein involved in hepatic lipid metabolism and affecting downstream signaling of Toll-like receptor 4 (TLR4) and PI3K/Akt activation. High resolution confocal microscopy revealed increased PTRF and TLR4 co-localization in hepatic small vessels of NAFLD + CIA rats. AAV9-mediated PTRF knockdown inhibited TLR4 signaling and alleviated hepatic fibrosis in NAFLD + CIA rats. Together, these findings indicate that NAFLD combined with CIA causes synovial injury and enhances non-alcoholic fatty liver fibrosis in rats. PTRF could attenuate the symptoms of NAFLD + CIA likely by affecting TLR4/PTRF co-expression and downstream signaling.

3.
J Ethnopharmacol ; 314: 116662, 2023 Oct 05.
Artículo en Inglés | MEDLINE | ID: mdl-37207880

RESUMEN

ETHNOPHARMACOLOGICAL RELEVANCE: Astragali Radix (AR), the root of Astragalus membranaceus (Fisch.) Bge. or Astragalus membranaceus (Fisch.) Bge. var. mongholicus (Bge.) Hsiao, known as Huangqi in traditional Chinese medicine, has been widely used in traditional Chinese medicine prescriptions for acute and chronic liver injury. AR was the most important medicine in a Chinese traditional prescription called Huangqi Decoction (HQD), has been used to treat chronic liver diseases since the 11th century. In particular, its major active ingredient, Astragalus polysaccharide (APS), has demonstrated promising effects on inhibiting hepatic fibrosis. However, to date, the effect of APS against alcohol-induced hepatic fibrosis and its underlying molecular mechanisms remains unknown. AIMS OF THE STUDY: This study aimed to explore the effect and potential molecular mechanisms of APS against alcohol-induced hepatic fibrosis by using network pharmacology and experimental validation. MATERIALS AND METHODS: The potential targets and underling mechanism of AR in alcoholic liver fibrosis were first predicted using network pharmacology, followed by experimental validation using SD rat model with alcohol-induced hepatic fibrosis. Further, the predicted candidate signaling pathways and potential target polymerase I and transcript release factor (PTRF) were combined to explore the multifaceted mechanism of APS against alcohol-induced hepatic fibrosis. Finally, overexpression of PTRF was explored to reveal the role of PTRF in the mechanism of APS against alcohol-induced hepatic fibrosis. RESULT: APS exerted potent anti-hepatic fibrosis effects by downregulating genes involved in the Toll-like receptor 4 (TLR4)/JNK/NF-κB/MyD88 pathway. Notably, APS treatment ameliorated the hepatic damage by inhibiting the overexpression of PTRF and decreasing the co-localisation of TLR4/PTRF. Overexpression of PTRF induced reversal of the protective effects of APS on alcohol-induced hepatic fibrosis. CONCLUSION: This study indicated that APS may alleviate alcohol-induced hepatic fibrosis by inhibiting the activation of PTRF and TLR4/JNK/NF-κB/MyD88 pathway, which provides a scientific elucidation for the mechanisms of APS on the anti-hepatic fibrosis activity and presents a promising therapeutic approach for treating hepatic fibrosis.


Asunto(s)
Planta del Astrágalo , FN-kappa B , Ratas , Animales , FN-kappa B/metabolismo , Factor 88 de Diferenciación Mieloide/metabolismo , Receptor Toll-Like 4/metabolismo , Ratas Sprague-Dawley , Cirrosis Hepática/inducido químicamente , Cirrosis Hepática/tratamiento farmacológico , Polisacáridos/farmacología
4.
J Environ Manage ; 338: 117778, 2023 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-37019021

RESUMEN

Source contributions and regional transport of maximum daily average 8-h (MDA8) O3 during a high O3 month (June 2019) in Henan province in central China are explored using a source-oriented Community Multiscale Air Quality (CMAQ) model. The monthly average MDA8 O3 exceeds ∼70 ppb in more than half of the areas and shows a clear spatial gradient, with lower O3 concentrations in the southwest and higher in the northeast. Significant contributions of anthropogenic emissions to monthly average MDA8 O3 concentrations of more than 20 ppb are predicted in the provincial capital Zhengzhou, mostly due to emissions from the transportation sector (∼50%) and in the areas in the north and northeast regions where industrial and power generation-related emissions are high. Biogenic emissions in the region only contribute to approximately 1-3 ppb of monthly average MDA8 O3. In industrial areas north of the province, their contributions reach 5-7 ppb. Two CMAQ-based O3-NOx-VOCs sensitivity assessments (the local O3 sensitivity ratios based on the direct decoupled method and the production ratio of H2O2 to HNO3) and the satellite HCHO to NO2 column density ratio consistently show that most of the areas in Henan are in NOx-limited regime. In contrast, the high O3 concentration areas in the north and at the city centers are in the VOC-limited or transition regimes. The results from this study suggest that although reducing NOx emissions to reduce O3 pollution in the region is desired in most areas, VOC reductions must be applied to urban and industrial regions. Source apportionment simulations with and without Henan anthropogenic emissions show that the benefit of local anthropogenic NOx reduction might be lower than expected from the source apportionment results because the contributions of Henan background O3 increase in response to the reduced local anthropogenic emissions due to less NO titration. Thus, collaborative O3 controls in neighboring provinces are needed to reduce O3 pollution problems in Henan effectively.


Asunto(s)
Contaminantes Atmosféricos , Contaminación del Aire , Ozono , Contaminantes Atmosféricos/análisis , Contaminación del Aire/estadística & datos numéricos , China , Monitoreo del Ambiente/métodos , Peróxido de Hidrógeno , Ozono/análisis , Compuestos Orgánicos Volátiles/análisis
5.
Cogn Neurodyn ; 16(6): 1505-1524, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36408077

RESUMEN

In general, inhibitory stimuli are thought to inhibit neuronal firing, but they may actually enhance firing sometimes, such as post-inhibitory rebound spike (PIR spike) and post-inhibitory facilitation (PIF) phenomena, which play an important role in human neuronal activities. We study responses to inhibitory pulse in a classical neuron model (Quartic adaptive Integrate-and-fire model) well known to reproduce a number of biologically realistic behaviors. The three phenomena that we study are PIR, in which a neuron fires after an inhibitory pulse, and PIF, in which a subthreshold excitatory input can induce a spike if it is applied with proper timing after an inhibitory pulse, as well as period firing after inhibitory pulse. When the system features focus and saddle two equilibriums, the three phenomena will be occurred under the inhibitory pulse, while all three phenomena will not be induced when the system features node and saddle two equilibriums. Using dynamical systems theory, we explain the threshold mechanism of enhancement of neural firing response induced by inhibitory pulse and analyze the origin of these phenomena from several factors. We also describe the geometric characterization of dynamical structures of these three phenomena. This study therefore enrich the paradoxical phenomena that induced by inhibitory input and advance our understanding of its role.

6.
Artículo en Inglés | MEDLINE | ID: mdl-36225193

RESUMEN

Postinfectious irritable bowel syndrome (PI-IBS) is a highly prevalent gastrointestinal disorder associated with immune dysregulation and depression- and anxiety-like behaviors. Through traditional medicine, the active ingredient of Paeoniae Radix called paeoniflorin (PF) was previously found to prevent the symptoms of PI-IBS. However, there is limited information on the effects of PF on intestinal function and depression- and anxiety-like symptoms in PI-IBS animal models. Here, we aimed to determine the effects of PF treatment on the symptoms of PI-IBS in a rat model. The PI-IBS rat model was established via early postnatal sibling deprivation (EPSD), trinitrobenzenesulfonic acid (TNBS), and chronic unpredictable mild stress (CUMS) stimulation and then treated with different dosages of PF (10, 20, and 40 mg/kg) and leptin (1 and 10 mg/kg). The fecal water content and body weight were measured to evaluate the intestinal function, while the two-bottle test for sucrose intake, open field test (OFT), and elevated plus maze test (EMT) were performed to assess behavioral changes. The serum leptin levels were also measured using an enzyme-linked immunosorbent assay. Furthermore, the expressions of leptin and its receptor, LepRb, were detected in colonic mucosal tissues through an immunohistochemical assay. The activation of the PI3K/AKT signaling pathway and the expression of brain-derived neurotrophic factor (BDNF) were also detected via western blotting. After the experimental period, the PI-IBS rats presented decreased body weight and increased fecal water content, which coincided with elevated leptin levels and heightened depression- and anxiety-like behaviors (e.g., low sucrose intake, less frequency in the center areas during OFT, and fewer activities in the open arms during EMT). However, the PF treatment ameliorated these observed symptoms. Furthermore, PF not only inhibited leptin/LepRb expression but also reduced the PI3K/AKT phosphorylation and BDNF expression in PI-IBS rats. Notably, cotreatment with leptin (10 mg/kg) reduced the effects of PF (20 mg/kg) on colonic fibrosis, leptin/LepRb expression, and PI3K/AKT activation. Therefore, our findings suggest that leptin is targeted by PF via the leptin/LepRb pathway, consequently ameliorating the symptoms of PI-IBS. Our study also contributes novel insights for elucidating the pharmacological action of PF on gastrointestinal disorders and may be used for the clinical treatment of PI-IBS in the future.

7.
Huan Jing Ke Xue ; 43(8): 3953-3965, 2022 Aug 08.
Artículo en Chino | MEDLINE | ID: mdl-35971694

RESUMEN

Air pollution in Henan province is serious and is significantly impacted by pollution transmission and interactions with surrounding areas. The emission sources in 18 cities in Henan province were labeled and applied to the WRF-CMAQ traceability model for simulation in January, April, July, and October of 2017. The pollutant distribution results showed that due to the combined influence of emissions and meteorology, the concentrations of PM2.5, NO2, and SO2 in Henan province were the highest in winter and the lowest in summer. The seasonal variation in O3-8h concentration was the highest in summer, followed by spring, and the lowest in winter. There was a large difference in pollutant concentrations between different seasons. The average concentrations of PM2.5, NO2, and SO2 in winter in Henan province were 4.17, 4.12, and 6.24 times those in summer, respectively, whereas the concentration of O3-8h in summer was 2.24 times that in winter. Since PM2.5, NO2, and SO2 are closely related to primary emissions and have a certain homology, the distributions of high values of these three pollutants were higher in the north and lower in the south, and the seasonal trends were more consistent. The seasonal distribution of O3-8h varied widely, with high O3-8h values mainly distributed in the northeastern region of Henan province in summer, when meteorological conditions contributed to O3 production; in winter, spring, and autumn, high O3-8h values were mainly distributed in the southern part of Henan province due to the suppression of meteorological conditions and NOx consumption. The results of the study on the transport of pollutants showed that extra-provincial transport and natural sources contributed the most to the concentrations of PM2.5, O3-8h, NO2, and SO2 in winter, with 36.20%-72.32%, 77.96%-96.08%, 49.45%-78.80%, and 59.05%-88.85%, respectively. When considering only local emissions and intra-provincial transmission, the contributions of emissions to local concentrations of the four pollutants in summer were the highest in all cities of Henan province. The contributions of intra-provincial transmission to PM2.5 and O3-8h in spring were the largest, with 25.63%-74.69% and 30.21%-80.01%, respectively, and the contributions of intra-provincial transmission to NO2 and SO2 in winter were larger, with 26.02%-76.96% and 20.30%-82.34%. The transmission paths of PM2.5, NO2, and SO2 were more similar in Henan province, with more transmission from north to south in winter, from west to east and southwest to northeast in spring, from southwest to northeast in summer, and from north to south in autumn; however, the transmission of PM2.5 was more complicated. The O3-8h transport path was more different from the others, especially in autumn when pollutants were mostly transported from north to south, but the O3-8h transport path from southwest to northeast was obvious.


Asunto(s)
Contaminantes Atmosféricos , Contaminación del Aire , Contaminantes Atmosféricos/análisis , Contaminación del Aire/análisis , China , Ciudades , Monitoreo del Ambiente/métodos , Dióxido de Nitrógeno , Material Particulado/análisis , Estaciones del Año
8.
J Texture Stud ; 53(1): 96-107, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-34750817

RESUMEN

The lubricities of glycerol solutions with different viscosities were investigated at various frictional pairs, speeds, and loads to explore the lubrication regulations of diverse foods in mouths of different people. The friction pairs were characterized in terms of mechanical properties, surface morphology, and hydrophobicity. The results showed that the partial or complete Stribeck curves occurred with different speeds and viscosities. Various friction pairs had great influences on the boundary lubrication zone, but little influences on the elastohydrodynamic lubrication (EHL) zone. Increasing loads caused the friction coefficient decreasing in boundary lubrication zone; however, the friction coefficient changed a little in the mixed lubrication and EHL zones.


Asunto(s)
Lubrificación , Fricción , Humanos , Interacciones Hidrofóbicas e Hidrofílicas , Propiedades de Superficie , Viscosidad
9.
Front Pharmacol ; 12: 724410, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34690766

RESUMEN

Background: Accumulating evidence suggests that the polymerase I and transcript release factor (PTRF), a key component of the caveolae structure on the plasma membrane, plays a pivotal role in suppressing the progression of colorectal cancers. However, the role of PTRF in the development of functional gastrointestinal (GI) disorders remains unclear. Post-infectious irritable bowel syndrome (PI-IBS) is a common functional GI disorder that occurs after an acute GI infection. Here, we focused on the role of PTRF in the occurrence of PI-IBS and investigated the underlying mechanisms. Methods: Lipopolysaccharide (LPS) (5 µg/ml) was used to induce inflammatory injury in human primary colonic epithelial cells (HCoEpiCs). Furthermore, a rat model of PI-IBS was used to study the role of PTRF. Intestinal sensitivity was assessed based on the fecal water content. A two-bottle sucrose intake test was used to evaluate behavioral changes. Furthermore, shRNA-mediated knockdown of PTRF was performed both in vitro and in vivo. We detected the expression of PTRF in colonic mucosal tissues through immunohistochemistry (IHC), western blotting (WB), and immunofluorescence (IF) analysis. Luciferase activity was quantified using a luciferase assay. Co-localization of PTRF and Toll-like receptor 4 (TLR4) was detected using IF analysis. The activation of the signaling pathways downstream of TLR4, including the iNOs, p38, extracellular signal-regulated kinase (ERK), and c-Jun N-terminal kinase (JNK) pathways, was detected via WB. The levels of NO, IL-1ß, IL-6, and TNF-α were measured using enzyme-linked immunosorbent assays. Results: LPS significantly induced PTRF expression and signaling downstream of TLR4, including p38, ERK, and JNK pathways, in HCoEpiCs. Moreover, shRNA-mediated knockdown of PTRF in HCoEpiCs significantly decreased the phosphorylation of JNK, ERK, and p38 and iNOS expression. In PI-IBS rats, the lack of PTRF not only reduced fecal water content and suppressed depressive behavior but also increased the body weight. Furthermore, we found a strong co-localization pattern for PTRF and TLR4. Consistently, the lack of PTRF impaired TLR4 signaling, as shown by the decreased levels of p-JNK, p-ERK, and p-p38, which are upstream factors involved in iNOS expression. Conclusion: PTRF promoted PI-IBS and stimulated TLR4 signaling both in vitro and in vivo. The results of this study not only enlighten the pathogenesis of PI-IBS but also help us understand the biological activity of PTRF and provide an important basis for the clinical treatment of PI-IBS by targeting PTRF.

10.
Appl Opt ; 60(21): 6140-6146, 2021 Jul 20.
Artículo en Inglés | MEDLINE | ID: mdl-34613278

RESUMEN

The laser-induced fluorescence (LIF) technique, which has been widely used for food testing, can be combined with various algorithms to classify and recognize different kinds of honey. This paper proposes the Kolmogorov-Smirnov test-Gaussian mixture model (KS-GMM) algorithm, which is coupled with the LIF technique to realize accurate classification and recognition of different types of pure honey. The experiments are designed and carried out to obtain a set of LIF spectrum data from various honey and syrup samples. The proposed KS-GMM algorithm is applied for classification and recognition, with GMM, k-nearest neighbor (kNN), and decision tree algorithms as cross-validation methods. By comparing recognition results of training sets containing different amounts of data, it is found that the KS-GMM algorithm exhibits a maximum recognition accuracy of 96.52%. The research results prove that the KS-GMM algorithm outperforms, to the best of our knowledge, the other three algorithms in classifying and recognizing the honey types.


Asunto(s)
Algoritmos , Miel/clasificación , Rayos Láser , Distribución Normal , Espectrometría de Fluorescencia , Estadísticas no Paramétricas , Fluorescencia , Miel/análisis , Reproducibilidad de los Resultados
11.
Huan Jing Ke Xue ; 42(9): 4126-4139, 2021 Sep 08.
Artículo en Chino | MEDLINE | ID: mdl-34414711

RESUMEN

To reduce the risks of COVID-19 on society and the health of the general public, necessary prevention and control measures were implemented throughout China in 2020. Consequently, air quality was greatly improved due to lower emissions. However, the improvement of air quality could also be closely related to meteorological conditions. During quarantine (January 27 to February, 2020), reductions were observed in the concentration of all air pollutants in Henan Province (PM2.5, PM10, SO2, CO, and NO2 decreased by 36.89%, 34.18%, 19.43%, 29.85%, and 58.51%, respectively) relative to measurements taken from January 1 to 26, 2020. The only exception was for the concentration of O3, which increased by 69.64%. This study evaluates the importance of meteorological conditions in air pollution, through simulation with a long-and-short-term memory network (LSTM) and a machine learning algorithm. Results show that meteorological conditions play a crucial role in air pollutant formation. Given favorable meteorological factors, the concentrations of pollutants could be reduced by 15%-30%, while the reduction due to anthropogenic emission control ranges from 6%-40%. During the epidemic, meteorological conditions and human emissions accounted for 34.84% and 34.81% of the increase in O3 concentration, respectively. The results show that primary pollutant concentrations are more sensitive to the intensity of anthropogenic emissions. However, secondary pollutants are more dependent on meteorological factors. Furthermore, a nonlinear relationship has been identified between O3 concentration and to emission intensity. Further investigation into the causes of the rise in O3 concentration is necessary to gain a greater understanding and better control of particulate matter and O3 pollution.


Asunto(s)
Contaminación del Aire , COVID-19 , Algoritmos , Humanos , Aprendizaje Automático , Pandemias , SARS-CoV-2
12.
Appl Opt ; 60(14): 4120-4126, 2021 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-33983164

RESUMEN

Accurate and rapid spectrum fitting is very important for quantitatively analyzing laser-induced breakdown spectroscopy (LIBS). The Voigt function is often used to fit LIBS spectral lines. We propose a new approximate Voigt function formula. Based on the classic Lorentz-Gauss linear combination formula, a summation term was added that contained a specific convolution operation to improve the Voigt function's calculation and fitting accuracy. This formula can be used for the approximate calculation of the Voigt function with an overall accuracy of 0.31% and a full width at half-maximum internal accuracy of 0.25% when the ratio of Lorentzian linewidth to Gaussian linewidth is 1:1. The formula was then applied to LIBS data processing to fit four element spectral lines of calcium (Ca-393.37, 396.85, and 422.67 nm) and potassium (K-766.49 nm). The fitting results showed that this new approximate formula could fit at least seven data points, and compared with the complex plane partition method and the classic linear combination formula, the new formula had better fitting speed and accuracy.

13.
Huan Jing Ke Xue ; 42(2): 513-522, 2021 Feb 08.
Artículo en Chino | MEDLINE | ID: mdl-33742845

RESUMEN

To evaluate the health benefits brought about by air environmental treatment and determine the main drivers of health risk, we calculated the health and economic benefits attributed to PM2.5 control in Eastern and Central China from 2013 to 2017 by combining PM2.5 concentrations with a human activity enhanced exposure-response model. The relative contributions of changes in four factors related to the PM2.5 health burden were also quantified, namely total population, population aging, baseline mortality rates, and ambient exposure. The results show that the population weighted PM2.5 concentration decreased by 28.73% and the proportion of the population exposed to annual PM2.5 concentrations lower than or equal to 35 µg·m-3 increased from 11.23% to 27.91% across the study area during this period. Avoided deaths were decreased to 14.43%, which equates to avoided economic losses of approximately 559 billion RMB. If PM2.5 concentration meets the Chinese Ambient Air Quality Standard Grade Ⅱ (35 µg·m-3) or Grade Ⅰ (15 µg·m-3), or the World Health Organization Air Quality Guidelines (AQG) standards (10 µg·m-3), a 8.22%, 55.05%, and 79.36% reduction in the total deaths could be achieved in the base year (2017) with equivalent total economic benefits of approximately 319, 2137, and 3081 billion RMB, respectively. Total population, population aging, baseline mortality rates, and PM2.5 concentrations contributed -2.69%, -12.38%, 1.66%, and 14.57% to PM2.5-related deaths. Overall, during the study period, the reduction in PM2.5 concentrations has been the main factor contributing to the reduction in the public health burden. China has implemented significant air pollution control measures; however, the health burden associated with high PM2.5 concentrations in densely populated areas is still extremely high, requiring an aggressive air pollution control strategy.


Asunto(s)
Contaminantes Atmosféricos , Contaminación del Aire , Contaminantes Atmosféricos/análisis , Contaminación del Aire/análisis , Contaminación del Aire/prevención & control , China , Exposición a Riesgos Ambientales , Humanos , Material Particulado/análisis , Salud Pública
14.
Sci Total Environ ; 757: 143885, 2021 Feb 25.
Artículo en Inglés | MEDLINE | ID: mdl-33310581

RESUMEN

In this study, molecular characteristics, source contributions, and health risks of polycyclic aromatic hydrocarbons (PAHs) in PM2.5 for four haze levels in Zhengzhou, a megacity in central China with severe air pollution problems, have been analyzed. The concentrations of PAHs and PM2.5 on heavy haze (HH) days were 63% and 122% higher than non-haze (NH) days. The occurrence of high PAH concentration was often accompanied by the northwest wind along with adverse meteorological conditions that limit regional dispersion. The source apportionment results indicated that almost all sources contributed more PAH concentration on haze days. In particular, coal combustion and vehicle emissions contributions were almost doubled on HH days. The incremental lifetime cancer risk (ILCR) of PAHs has been assessed. BaP and DahA showed relatively high contributions to ILCR, and 31%-48% of ILCR is due to exposure to PAHs on high HH days.

15.
J Texture Stud ; 52(1): 124-136, 2021 02.
Artículo en Inglés | MEDLINE | ID: mdl-33184839

RESUMEN

Drinking tastes and lubrication properties of Chinese rice wine (CRW) under different heating temperatures were studied by tribology tests, gas chromatography-mass spectrometry (GC-MS) and sensory evaluations. CRW's drinking tastes were evaluated by taste panelists. Flavor compounds were detected by GC-MS. Lubrication properties of CRW were measured by tribometer. Drinking tastes changed under different heating temperatures and were the best at 60°C assessed by panelists. Four key compounds, furfural, benzaldehyde, butanedioic acid diethyl ester, and phenylethyl alcohol, were determined by GC-MS affecting drinking tastes of CRW. Their variation trends were consistent with the changes of CRW's tastes. The variation of CRW's lubrication properties had a positive correlation with that of CRW's taste, especially astringency. The lowest friction coefficient implied the best lubrication performance and taste at 60°C. Therefore, it was possible to rapidly evaluate drinking tastes of CRW using tribology technology based on the results. Reasons for temperatures influencing CRW's lubrication properties and drinking tastes were also analyzed in this study.


Asunto(s)
Cromatografía de Gases y Espectrometría de Masas/métodos , Calefacción , Oryza/química , Gusto , Vino/análisis , Adulto , China , Ésteres , Aromatizantes , Humanos , Lubrificación , Masculino , Persona de Mediana Edad , Temperatura , Adulto Joven
16.
Front Pharmacol ; 11: 581230, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33597871

RESUMEN

Background: Triptolide (TP), a naturally derived compound from Tripterygium wilfordii, has been proven effective in protecting against cardiovascular system, but the molecular mechanisms underlying its protective effects are poorly understood. In the current study, we sought to test the potential protective role of TP in the regulation of vascular calcification in a rat model and explore whether TP attenuates medial vascular calcification by upregulating miRNA-204. Methods: Vitamin D3 plus nicotine (VDN) was used to induce a vascular calcification (VC) model of rat aorta. Von Kossa and Hematoxylin-Eosin staining were applied to assess the degree of calcification of rat aortas. Calcium content and alkaline phosphatase activity were measured. Quantitative reverse-transcription polymerase chain reaction (qRT-PCR) was applied to quantify miRNA-204 expression. The localization of runt-related transcription factor-2 (RUNX2) and bone morphogenetic protein-2 (BMP2) expressions were detected by immunohistochemistry and western blotting. Results: Administration of TP greatly reduced vascular calcification in a dose-dependent manner compared with VC controls. The increase in ALP activity and calcium content was ameliorated by TP. Moreover, protein expression levels of BMP2 and RUNX2 were significantly reduced in calcified aortas. MiRNA-204 expression was increased in the TP-treated groups compared with VC controls and the effects of TP were reversed by the intravenous injection of miRNA-204-interfering lentivirus. However, the miRNA-204-overexpressing lentivirus had no additional effects on ALP activity, calcium content, BMP2 and RUNX2 expressions compared with those from TP group. Conclusion: TP inhibited BMP2 and RUNX2 expression and attenuated vascular calcification via upregulating the level of miRNA-204. TP appears to be a potential new therapeutic option for treating vascular calcification.

17.
Food Chem ; 309: 125669, 2020 Mar 30.
Artículo en Inglés | MEDLINE | ID: mdl-31683148

RESUMEN

The fluorescence spectra of oil samples were obtained by laser-induced fluorescence spectroscopy and thermal oxidation stoichiometry at room temperature and 80 °C respectively. The Support Vector Machine, combined with Principal Component Analysis-Linear Discriminant Analysis (PCA-LDA), could distinguish pure extra virgin olive oils (EVOO) from oils adulterated with 2% soybean oil, with a recognition rate of 100%. Besides, as the intensity of the fluorescence spectra and concentration of the adulterants showed a non-linear relationship, linear dimension reduction methods may lead to overlapping of the different adulterated concentrations features, resulting in large errors in quantifying adulteration. In this paper, Kernel Principal Component Analysis-Linear Discriminant Analysis (KPCA-LDA) was applied instead of PCA-LDA to extract fluorescence spectra features, and a Partial Least Squares Regression model was established, which could quantify adulterants such as low percentages of soybean oil in EVOO. The coefficient of determination and root mean squared error were 0.92 and 2.72%, respectively.


Asunto(s)
Contaminación de Alimentos/análisis , Rayos Láser , Aceite de Oliva/química , Espectrometría de Fluorescencia/métodos , Análisis Discriminante , Análisis de los Mínimos Cuadrados , Oxidación-Reducción , Análisis de Componente Principal , Aceite de Soja/química , Temperatura
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