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1.
Sci Total Environ ; 904: 166747, 2023 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-37659526

RESUMEN

Based on in-situ measurement of black carbon (BC) and carbon monoxide (CO), the characteristics of BC emissions and wet scavenging were comprehensively investigated in Nanning, South China. The average annual BC concentration was 1.02 ± 0.53 µg m-3 with higher pollution levels during winter. In winter, a higher net BC/CO (ΔBC/ΔCO) ratio of 3.3 ± 0.3 ng m-3 ppb-1 along with an increased absorption Ångström exponent (AAE) and BC mass from biomass burning (BCbb), indicated a significant contribution of biomass burning to BC emissions. However, emissions from the traffic sector consistently exerted a dominant influence throughout the year. Cluster analysis of backward trajectories identified three types of air masses with distinct origins. Cluster #1 originated from Guangxi province and its vicinity, intermittently influencing the sampling site throughout the year with varying effects between winter and summer. This air mass brought in clean sea breeze in summer whereas transported a higher proportion of BCbb to the site during wintertime due to local open biomass burning. Cluster #3 primarily arrived in autumn and winter (October-December) from polluted central China, resulting in substantially high BC mass at the site. Cluster #2 coincided with the period (January-March) when extensive surface open biomass burning events occurred in Southeast Asia (SEA) regions. These BC aerosols in cluster#2 initially rose to higher altitudes above SEA before being regionally transported, but were significantly scavenged by clouds and precipitation during vertical uplift. The remaining BC exhibited a notably lower BC loss rate on relative humidity (RH) of -0.01 ng m-3 ppb-1 %-1 compared to cluster #1 (-0.03) and cluster #3 (-0.06), corresponding to an average BC transport efficiency of 0.85, 0.73, and 0.53, respectively. Nonetheless, air masses in cluster #2 could still transport considerably high BC mass to Nanning due to dry conditions and less wet scavenging along trajectory pathways. These findings provide valuable insights for policymakers and government officials in regulating and mitigating BC pollution in South China.

2.
Eur J Pediatr Surg ; 33(5): 386-394, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-36379465

RESUMEN

OBJECTIVE: To discover the mechanism of the sirtuin 1 (SIRT1)-mediated nuclear factor-κB (NF-κB) pathway in the protection against necrotizing enterocolitis (NEC) in neonatal mice. MATERIALS AND METHODS: Neonatal mice were treated with EX527 (an inhibitor of SIRT1) and/or pyrrolidine dithiocarbamate (PDTC, an inhibitor of NF-κB). The survival rate of the mice was recorded. Hematoxylin and eosin (HE) staining was performed to observe the pathological changes in the intestines. Furthermore, western blotting, enzyme-linked immunosorbent assay, and real-time quantitative polymerase chain reaction were conducted to measure the protein and gene expression, while corresponding kits were used to detect the levels of oxidative stress indicators. RESULTS: PDTC increased the survival rate of NEC mice. When compared with the NEC+ EX527 + PDTC group, the histological NEC score was higher in the NEC + EX527 group but lower in the NEC + PDTC group. SIRT1 expression in the intestines of NEC mice was downregulated, with an increase in p65 nuclear translocation. Additionally, malondialdehyde increased and glutathione peroxidase decreased in the intestines of NEC mice, with the upregulation of interleukin (IL)-6, IL-1ß, and tumor necrosis factor-α, as well as the downregulation of ZO-1, occludin, and claudin-4 in the intestines. However, the above changes could be improved by PDTC, which could be further reversed by EX527. CONCLUSION: SIRT1 can mitigate inflammation and the oxidative stress response and improve intestinal permeability by mediating the NF-κB pathway, playing an important role in the alleviation of NEC.


Asunto(s)
Enterocolitis Necrotizante , FN-kappa B , Sirtuina 1 , Animales , Ratones , Animales Recién Nacidos , Enterocolitis Necrotizante/metabolismo , FN-kappa B/genética , FN-kappa B/metabolismo , Transducción de Señal , Sirtuina 1/genética , Sirtuina 1/metabolismo , Factor de Necrosis Tumoral alfa
3.
Sci Total Environ ; 860: 160469, 2023 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-36464057

RESUMEN

Volatile organic compounds (VOCs) are precursors for ozone and secondary organic aerosol (SOA) formation, thereby playing a vital role in atmospheric chemistry and urban air quality. To characterize the relationship between VOCs and SOA, organics both in gas and particulate phases were concurrently measured in urban Beijing. The VOCs and organic aerosol (OA) were apportioned into factors with different oxidation levels by applying the factorization analysis on their detailed mass spectra. Six factors of VOCs were identified, including four primary VOCs (PVOC) factors and two secondary VOCs (SVOC) factors. The PVOC factors dominated the total VOCs when the air mass originated in the cleaner northern areas, while SVOC factors dominated for polluted southern air masses. The normalized concentrations of PVOC and primary OA factors showed consistent diurnal variations regardless of air mass directions, owing to the relatively stable local emissions during the experimental period. This contrasted with the secondary factors due to more complex transformation processes. The traffic-related VOCs and solid fuel combustion VOCs negatively correlated with SOA, implying that they may have contributed to the SOA formation through photooxidation. The VOCs in lower oxidation levels were found to have poor correlations with the less oxidized SOA, whereas they correlated strongly to the more oxidized SOA. This implied that the less oxidized SOA may be in a transition state, where its production and loss rates were balanced. These served as products of VOCs oxidation and reactants of more oxidized SOA formation, playing important roles on the VOC to SOA transformation. The identified VOC emission sources and their photochemical production of SOA should be considered in air quality policy planning.


Asunto(s)
Contaminantes Atmosféricos , Ozono , Compuestos Orgánicos Volátiles , Compuestos Orgánicos Volátiles/análisis , Contaminantes Atmosféricos/análisis , Beijing , Ozono/análisis , Aerosoles/análisis , China , Monitoreo del Ambiente
4.
Environ Sci Technol ; 56(18): 12873-12885, 2022 09 20.
Artículo en Inglés | MEDLINE | ID: mdl-36083258

RESUMEN

The light-absorbing organic aerosol (OA) constitutes an important fraction of absorbing components, counteracting major cooling effect of aerosols to climate. The mechanisms in linking the complex and changeable chemistry of OA with its absorbing properties remain to be elucidated. Here, by using solvent extraction, ambient OA from an urban environment was fractionated according to polarity, which was further nebulized and online characterized with compositions and absorbing properties. Water extracted high-polar compounds with a significantly higher oxygen to carbon ratio (O/C) than methanol extracts. A transition O/C of about 0.6 was found, below and above which the enhancement and reduction of OA absorptivity were observed with increasing O/C, occurring on the less polar and high polar compounds, respectively. In particular, the co-increase of nitrogen and oxygen elements suggests the important role of nitrogen-containing functional groups in enhancing the absorptivity of the less polar compounds (e.g., forming nitrogen-containing aromatics), while further oxidation (O/C > 0.6) on high-polar compounds likely led to fragmentation and bleaching chromophores. The results here may reconcile the previous observations about darkening or whitening chromophores of brown carbon, and the parametrization of O/C has the potential to link the changing chemistry of OA with its polarity and absorbing properties.


Asunto(s)
Contaminantes Atmosféricos , Metanol , Aerosoles/análisis , Contaminantes Atmosféricos/análisis , Carbono/análisis , Nitrógeno , Oxígeno , Material Particulado/análisis , Solventes , Agua/química
5.
Sci Total Environ ; 847: 157529, 2022 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-35872195

RESUMEN

Black carbon (BC) aerosols have effects on the atmospheric thermal vertical structure due to its radiation absorption characteristics, hereby influencing the boundary layer characteristics and pollutant diffusion. This study focuses on the BC effects under different atmospheric conditions on air quality and vertical meteorological conditions. Four days flight observation combined with surface wind profiler radar data were used to investigate the vertical profiles of BC and wind speed over Beijing urban area in early summer. The vertical profiles of BC concentration and wind speed in the boundary layer had a negative correlation, both having abrupt changes near the boundary layer height under stagnant weather conditions. The chemical transport model showed the increase of BC under stagnant conditions could cause aggravation of the stability of the boundary layer, thereby increasing the accumulation of pollutants. In particular, BC leads to the changes in the temperature profile, which will modify relative humidity and indirectly lead to the changes in the vertical profile of aerosol optical properties. However, if the early accumulation of BC was absent under more turbulent conditions, the effects of BC on air quality and meteorological conditions were limited.


Asunto(s)
Contaminantes Atmosféricos , Contaminación del Aire , Aerosoles/análisis , Contaminantes Atmosféricos/análisis , Contaminación del Aire/análisis , Beijing , Carbono/análisis , Monitoreo del Ambiente , Conceptos Meteorológicos , Material Particulado/análisis , Hollín
6.
Sci Rep ; 12(1): 7773, 2022 05 11.
Artículo en Inglés | MEDLINE | ID: mdl-35545654

RESUMEN

Overcoming resistance to alkylating agents has important clinical significance in glioma. Cyanidin-3-O-glucoside (C3G) has a tumor-suppressive effect on tumor cells. However, whether it plays a role in temozolomide resistance in glioma is still unclear. We constructed a TMZ-resistant LN-18/TR glioma cell line, observed the effect of C3G on TMZ resistance in this cell line, and explored the role of miR-214-5p in chemoresistance. Results showed that ß-catenin and MGMT were significantly upregulated in LN-18/TR cells. C3G upregulated miR-214-5p and enhanced the cytotoxic effect of temozolomide on LN-18/TR cells. Contrarily, C3G downregulated ß-catenin and MGMT. Moreover, the miR-214-5p mimic downregulated ß-catenin and MGMT in LN-18/TR cells, whereas the miR-214-5p inhibitor had the opposite effect; the miR-214-5p inhibitor significantly blocked the C3G-induced downregulation of ß-catenin and MGMT. C3G or the miR-214-5p mimic enhanced temozolomide-induced apoptosis in LN-18/TR cells, whereas the miR-214-5p inhibitor blocked this effect. Furthermore, C3G or miR-214-5p agomir combined with TMZ significantly inhibited the growth of LN-18/TR tumors. Collectively, our research discovered the potential signaling mechanism associated with C3G-mediated suppression of TMZ resistance in LN-18/TR cells through miR-214-5p, which can facilitate the treatment of MGMT-induced resistance in glioma cells.


Asunto(s)
Neoplasias Encefálicas , Glioma , MicroARNs , Antocianinas , Antineoplásicos Alquilantes/farmacología , Antineoplásicos Alquilantes/uso terapéutico , Apoptosis/genética , Neoplasias Encefálicas/tratamiento farmacológico , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patología , Línea Celular Tumoral , Metilasas de Modificación del ADN/genética , Enzimas Reparadoras del ADN , Resistencia a Antineoplásicos/genética , Regulación Neoplásica de la Expresión Génica , Glioma/tratamiento farmacológico , Glioma/genética , Glioma/patología , Glucósidos/farmacología , Glucósidos/uso terapéutico , Humanos , MicroARNs/metabolismo , Temozolomida/farmacología , Temozolomida/uso terapéutico , Proteínas Supresoras de Tumor/genética , beta Catenina/genética , beta Catenina/metabolismo
7.
Huan Jing Ke Xue ; 43(1): 46-60, 2022 Jan 08.
Artículo en Chino | MEDLINE | ID: mdl-34989489

RESUMEN

In order to investigate the chemical composition and source apportionment of aerosols during winter in the Beijing-Tianjin-Heibei region, the particular matter (PM) and aerosol chemical composition at Mt. Haituo were observed by using a GRIMM 180, a single-particle soot photometer (SP2), and a high-resolution time-of-flight aerosol mass spectrometer (HR-TOF-AMS) from December 28, 2020 to February 3, 2021. Combining these observations with meteorological data and the HYSPLIT model, we calculated the potential source contribution factor (PSCF) and concentration weighted trajectory (CWT) and analyzed the temporal evolution and potential sources apportionment of PM and aerosol chemical composition under different pollution processes. The results showed that the dust storm process mainly affected PM10 and PM2.5 in Mt. Haituo during the winter and had a small impact on PM1; by contrast, haze pollution mainly affected PM1. Chemical components of aerosol accounted for 85.0% and 73.4% of PM1 on clean and haze days, respectively, but only 47.4% of PM1 in dust storm processes. NO3- was the chemical component with the largest mass concentration in haze, accounting for 25.2% of PM1; black carbon (BC) had the largest mass concentration on clean and dust storm days, accounting for 24.1% and 12.8% of PM1, respectively. The median diameters of BC were 209.7, 207.5, and 204.7 nm on clean, dust storm, and haze days, respectively. Dp/Dc was 2.15 in haze pollution, which was 1.38 and 1.39 times that on dust storm and clean days, respectively. Diurnal variations in PM and aerosol chemical components were different during the different processes. PM10 and PM2.5had high mass concentrations at night and low mass concentrations during the daytime on clean and dust storm days and had a unimodal distribution with a peak at 14:00 in haze. Diurnal variations in chemical composition had a unimodal distribution on clean days and a bimodal distribution on dust storm and haze days. The chemical compositions of the BC coating layer were different under different processes. The coating layers of BC were mainly NH4NO3, (NH4)2SO4, and organic matter on the clean, dust storm, and haze days, respectively. The distribution of potential sources of PM1 and its chemical components were different under different processes. The high-value area of the potential sources was mainly concentrated in the Beijing-Baoding-Shijiazhuang-Yangquan area in the southwestern portion of the site during dust storms and was mainly concentrated in Yanqing, Huailai, and Changping in the areas around the site during haze.


Asunto(s)
Contaminantes Atmosféricos , Aerosoles/análisis , Contaminantes Atmosféricos/análisis , Beijing , China , Monitoreo del Ambiente , Material Particulado/análisis , Estaciones del Año
8.
Huan Jing Ke Xue ; 42(11): 5109-5121, 2021 Nov 08.
Artículo en Chino | MEDLINE | ID: mdl-34708950

RESUMEN

To control the spread of the 2019 novel coronavirus(COVID-19), China imposed rigorous restrictions, which resulted in great reductions in pollutant emissions. However, two heavy haze pollution episodes still occurred in Beijing. In this study, we use the air pollutants, aerosol number concentration, and meteorological elements data in Beijing, combined with the HYSPLIT model, to calculate the potential source contribution factor(PSCF) and concentration weight trajectory(CWT), and analyze the characteristics of evolution and potential source apportionment of atmospheric pollutants during the two episodes. The COVID-19 lockdown restrictions had great impacts on the diurnal variations of PM2.5 and black carbon(BC), while small impacts on the diurnal variations of CO, NO2, SO2, and O3. The primary pollutant was PM2.5 during the two haze pollution episodes, and the haze1 episode was mainly local pollution, while haze 2 was mainly local and external transportation pollution. The spectrum of aerosol number concentration was unimodal under different processes, with the peak located at 0.3 µm. During the haze episodes, the number concentration in the size range of 0.2-0.5 µm increased 3.3-13.6 times that of the clean days. The mass concentration contributions of BCliquid to BC in different processes were 64.8%-85.1%. This mass concentration of BCliquid ranked in the order of haze 1(5.04 µg·m-3) >haze 1(3.20 µg·m-3) >clean day(before COVID-19) (2.31 µg·m-3) >clean day(COVID-19) (0.76 µg·m-3). The characteristics of PSCF and CWT distribution of PM2.5 and BC were different in different processes. The PSCF high value areas of PM2.5 on the clean day(before COVID-19) and the clean day(COVID-19) were mainly distributed in the southwest and western of Beijing, and the weight concentration exceeded 30 µg·m-3. The PSCF high value areas of PM2.5 during haze 1 and haze 2 were mainly distributed in Beijing and its surrounding areas and southwestern, when the weight concentration exceeded 90 µg·m-3. The PSCF high value areas of BC were mainly distributed in Beijing and its surrounding areas on clean days(before COVID-19), clean days(COVID-19) and haze 1, with weighted concentrations exceeding 2.4, 0.9 and, 4.5 µg·m-3, respectively. The PSCF high value areas of BC on haze 2 was distributed in the southwest of Beijing, and the weight concentration exceeded 5 µg·m-3.


Asunto(s)
Contaminantes Atmosféricos , Contaminación del Aire , COVID-19 , Contaminantes Ambientales , Aerosoles/análisis , Contaminantes Atmosféricos/análisis , Contaminación del Aire/análisis , Beijing , China , Control de Enfermedades Transmisibles , Monitoreo del Ambiente , Humanos , Material Particulado/análisis , SARS-CoV-2 , Estaciones del Año
9.
Environ Sci Technol ; 55(9): 5677-5688, 2021 05 04.
Artículo en Inglés | MEDLINE | ID: mdl-33874721

RESUMEN

Emissions of light-absorbing black carbon (BC) and organic aerosol (OA) from biomass burning are presented as complex mixtures, which introduce challenges in modeling their absorbing properties. In this study, we chose typical residential wood burning emission and used a novel designed chamber to investigate the early stage evolution of plumes from different burning phases under real ambient conditions. The detailed mixing state between BC and OA was evaluated, on the basis of which optical modeling was performed to achieve a closure of aerosol-absorbing properties. Intensive secondary OA (SOA) formation was observed under solar radiation. OA from flaming conditions showed a higher absorptivity than from smoldering conditions, as OA is mostly internally and externally mixed with BC, respectively. For flaming (smoldering), the imaginary refractive index of OA (kOA) was initially at 0.03 ± 0.01 (0.001) and 0.15 ± 0.02 (0.05 ± 0.02) at λ = 781 and 405 nm, respectively, with a half-decay time of 2-3 h in light but a <40% decrease under dark within 5 h. The production of less-absorbing SOA in the first 1-2 h and possible subsequent photobleaching of chromophores contributed to the decrease of kOA. The enhanced abundance but decreased absorptivity of coatings on BC resulted in a relatively maintainable absorptivity of BC-containing particles during evolution.


Asunto(s)
Contaminantes Atmosféricos , Madera , Aerosoles/análisis , Contaminantes Atmosféricos/análisis , Atmósfera , Biomasa , Carbono , Humo , Hollín/análisis , Madera/química
10.
Chemosphere ; 252: 126455, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-32197175

RESUMEN

Black carbon (BC) exerts important radiative effects over regions with intensive emissions. This study presents in-situ aircraft measurements of BC vertical profiles including mass loading, size distribution and mixing state, spanning a range of pollution levels in both warm and cold seasons over Beijing. The development of planetary boundary layer (PBL) influenced the properties of pollutants at low levels, and regional transport from the southwest elevated the pollution at higher altitudes. Thicker coatings of BC were associated with higher pollution in the PBL, where interactions between BC and other substances intensively took place. Considering the mixing state of BC, the absorption efficiency could be potentially increased by up to 86% and 60% in the PBL and lower free troposphere, respectively. Including a column-integrated absorption enhancement, the in-situ constrained absorption aerosol optical depth at wavelength 870 nm (AAOD870) improved the agreement with AERONET by 28%, but the in-situ measurement remained 19% lower. A radiative transfer model finds a BC heating rate of 0.1-0.3 K/d and 0.5-3.1 K/d for less and more polluted environments respectively, and the BC coating effect could positively introduce a +0.1-4.2 Wm-2 radiative forcing. The presence of aerosol layer enhanced the positive vertical gradient of heating rate by redistributing the actinic flux. In particular, this gradient was further enhanced by introducing thickly-coated BC at higher level during the regional transport events, which may promote the temperature inversion and further depress the PBL development on polluted days.


Asunto(s)
Contaminantes Atmosféricos/análisis , Monitoreo del Ambiente , Hollín/análisis , Aerosoles/análisis , Atmósfera , Beijing , Carbono , China , Estaciones del Año , Hollín/química
11.
Sci Total Environ ; 709: 136251, 2020 Mar 20.
Artículo en Inglés | MEDLINE | ID: mdl-31887513

RESUMEN

Black carbon aerosol plays an important role on absorbing shortwave solar radiation. The absorption of BC in urban environment with intensive anthropogenic emissions may modify the atmospheric thermodynamics by heating the planetary boundary layer (PBL), however the exact impacts are still largely uncertain due to lack of in-situ observations. Here we report the detailed in-situ characterization on vertical profiles of BC-related properties including the BC mass, size distribution and mixing state over Beijing by successive flights, during which a full process of haze initialization, development and ceasing were captured and processes of BC properties during this typical haze event was in detail investigated. We found the shallow PBL and the temperature inversion importantly enhanced the BC mass loading in the polluted day and these BC particles were significantly coated with mass ratio of coating over refractory BC increasing from about 1 to 10, whereas when the capping was released the BC was dispersed throughout the column and the coating was reduced. The coatings may cause the enhancement of BC absorption by 95% and introduce additional heating rate as high as 0.1 K/h during hazy day. The absorbing power efficiency and heat rate of BC showed positive vertical gradient during peak pollution, which may enhance the temperature inversion at upper level of the PBL. These results provide impacts of BC mixing state on atmospheric heating, and emphasize the importance of including BC mixing state, especially under highly polluted environment, to model the aerosol-boundary layer interaction over urban environment with high BC emission.

12.
World J Clin Cases ; 7(16): 2204-2216, 2019 Aug 26.
Artículo en Inglés | MEDLINE | ID: mdl-31531315

RESUMEN

BACKGROUND: In China, hepatitis B virus-related acute-on-chronic liver failure (HBV-ACLF) is the most common liver failure characterized by serious clinical syndromes of liver decompensation with a very high mortality. Bacterial and/or fungal infections are the most common complications that are associated with high short-term mortality. Bacterial translocation from the intestine, impaired hepatic clearance, and immune paralysis of circulating immune cells are thought to contribute to infectious complications in liver failure. The control of bacterial and fungal infections is the key to improving HBV-ACLF outcomes. Active prevention, early diagnosis, and timely treatment of bacterial and fungal infections are essential for treating HBV-ACLF. AIM: To investigate the frequency and role of bacterial and fungal infections in patients with HBV-ACLF. METHODS: Patients with HBV-ACLF hospitalized at Taihe Hospital, Hubei University of Medicine from January 2014 to December 2017 were retrospectively enrolled. Patient-related information was retrieved from the hospital case database, including general information, blood biochemistry, complications, etc. According to the occurrence of secondary infection or not, the patients were divided into an infection group and a non-infection group. The sites, types, and incidences of bacterial and fungal infections and the influence of infections on the prognosis of HBV-ACLF were statistically analyzed. The risk factors for infections were assessed by unconditional logistic regression. RESULTS: There were 174 cases of HBV-ACLF that met the enrollment criteria, of which 114 (65.52%) were diagnosed with infectious complications. Infections occurred in the abdominal cavity (87 cases), respiratory tract (51 cases), urinary tract (18 cases), and biliary tract (10 cases). Patients with infectious complications had a significantly higher 28-d mortality (70.18%, 80/114) than those without (40.00%, 24/60) (70.18% vs 40.00%, P < 0.05). And patients with infectious complications had a much higher incidence of non-infectious complications (54.39%, 62/114) (54.39% vs 15.00%, P < 0.05), leading to an extremely high 28-d mortality of 88.71% (55/62) (P < 0.05). The grade of liver failure, period of hospital stay ≥ 30 d, age ≥ 45 years, and percentage of neutrophils > 70% were identified as risk factors for infectious complications. CONCLUSION: The high incidence of infectious complications in patients with HBV-ACLF is associated with severity and deterioration of the disease and may contribute to the extremely high mortality of these patients.

13.
Environ Sci Technol ; 53(19): 11112-11121, 2019 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-31423774

RESUMEN

The size-resolved properties of atmospheric black carbon (BC) importantly determine its absorption capacity and cloud condensation nuclei (CCN) ability. This study reports comprehensive vertical profiles of BC size-related properties over the Beijing area (BJ) and Continental Europe (CE). BC mass loadings over CE were in the range of clean background over BJ. For both planetary boundary layer (PBL) and lower free troposphere, the BC mass median core diameter over BJ during the cold season was 0.21 ± 0.02 µm, larger than the warm season over BJ and CE (0.18 ± 0.01 µm), which may reflect seasonal differences in emissions. The BC coatings were positively correlated with the pollution level, with background BC having a smaller coated count median diameter (0.19 ± 0.01 µm). The modeled absorption enhancement (Eabs) due to coatings was 1.23 ± 0.14 for the background but in the PBL following a linear expression (Eabs = 0.13 × MassBC,surface + 1.26). The CCN ability of BC was significantly enhanced in the polluted PBL, due to both enlarged size and increased hygroscopicity. In polluted BJ at predicted supersaturations, ∼0.08% half of the BC number could be activated, whereas the cleaner environment needs ∼0.14%. The results here suggest that the highly coated and absorbing BC can be efficiently incorporated into clouds and can exert important indirect radiative impacts over the polluted East Asia region.


Asunto(s)
Contaminantes Atmosféricos , Aerosoles , Atmósfera , Carbono , Monitoreo del Ambiente , Europa (Continente) , Asia Oriental
14.
Cancer Biomark ; 22(3): 575-585, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29843222

RESUMEN

OBJECTIVE: To investigate the impact of Bmi-1-mediated NF-κB pathway on the biological characteristics of CD133+ liver cancer stem cells (LCSCs). METHODS: Flow cytometry was used to isolate CD133+ LCSC cells from Huh7, Hep3B, SK-hep1, and PLC/PRF-5 cells. CD133+ Huh7 cells were divided into Control, Blank, Bmi-1 siRNA, JSH-23 (NF-κB pathway inhibitor), and Bmi-1 + JSH-23 groups. The properties of CD133+ Huh7 cells were detected by the colony-formation and sphere-forming assays. Besides, Transwell assay was applied for the measurement of cell invasion and migration, immunofluorescence staining for the detection of NF-κB p65 nuclear translocation, and qRT-PCR and Western blotting for the determination of SOX2, NANOG, OCT4, Bmi-1, and NF-κB p65 expression. RESULTS: CD133+ Huh-7 cells were chosen as the experiment subjects after flow cytometry. Compared with CD133- Huh-7 cells, the expression of CD133, OCT4, SOX2, NANOG, Bmi-1, and NF-κB p65, the nuclear translocation of NF-κB p65, the number of cell colonies and Sphere formation, as well as the abilities of invasion and migration were observed to be increased in CD133+ Huh-7 cells, which was inhibited after treated with Bmi-1 siRNA or JSH-23, meanwhile, the cell cycle was arrested at the G0/G1 and S phases with apparently enhanced cell apoptosis. Importantly, no significant differences in the biological characteristics of CD133 + Huh-7 cells were found between the Blank group and Bmi-1 + JSH-23 group. CONCLUSION: Down-regulating Bmi-1 may inhibit the biological properties of CD133+ LCSC by blocking NF-κB signaling pathway, which lays a scientific foundation for the clinical treatment of liver cancer.


Asunto(s)
Antígeno AC133/metabolismo , Neoplasias Hepáticas/metabolismo , FN-kappa B/metabolismo , Células Madre Neoplásicas/metabolismo , Complejo Represivo Polycomb 1/metabolismo , Transducción de Señal , Apoptosis , Ciclo Celular , Línea Celular Tumoral , Técnica del Anticuerpo Fluorescente , Expresión Génica , Regulación Neoplásica de la Expresión Génica , Humanos , Neoplasias Hepáticas/genética , FN-kappa B/genética , Complejo Represivo Polycomb 1/genética
15.
Clinics (Sao Paulo) ; 72(11): 686-692, 2017 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-29236915

RESUMEN

OBJECTIVE: To investigate the impact of the baseline status of patients with hepatitis B virus-associated acute-on-chronic liver failure on short-term outcomes. METHODS: A retrospective study was conducted that included a total of 138 patients with hepatitis B virus-associated acute-on-chronic liver failure admitted to the Department of Infectious Diseases, Taihe Hospital, Hubei University of Medicine, from November 2013 to October 2016. The patients were divided into a poor prognosis group (74 patients) and a good prognosis group (64 patients) based on the disease outcome. General information, clinical indicators and prognostic scores of the patients' baseline status were analyzed, and a prediction model was established accordingly. RESULTS: Elder age, treatment with artificial liver support systems and the frequency of such treatments, high levels of white blood cells, neutrophils, neutrophil count/lymphocyte count ratio, alanine aminotransferase, gamma-glutamyl transferase, total bilirubin, urea, and prognostic scores as well as low levels of albumin and sodium were all significantly associated with the short-term outcomes of hepatitis B virus-associated acute-on-chronic liver failure. The predictive model showed that logit (p) = 3.068 + 1.003 × neutrophil count/lymphocyte count ratio - 0.892 × gamma-glutamyl transferase - 1.138 × albumin - 1.364 × sodium + 1.651 × artificial liver support therapy. CONCLUSION: The neutrophil count/lymphocyte count ratio and serum levels of gamma-glutamyl transferase, albumin and sodium were independent risk factors predicting short-term outcomes of hepatitis B virus-associated acute-on-chronic liver failure, and the administration of multiple treatments with artificial liver support therapy during the early stage is conducive to improved short-term outcomes.


Asunto(s)
Insuficiencia Hepática Crónica Agudizada/virología , Hepatitis B/complicaciones , Insuficiencia Hepática Crónica Agudizada/sangre , Insuficiencia Hepática Crónica Agudizada/mortalidad , Insuficiencia Hepática Crónica Agudizada/terapia , Adulto , Femenino , Hepatitis B/sangre , Hepatitis B/mortalidad , Hepatitis B/terapia , Humanos , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Pronóstico , Estudios Retrospectivos , Factores de Riesgo , Sensibilidad y Especificidad
16.
Clinics ; 72(11): 686-692, Nov. 2017. tab, graf
Artículo en Inglés | LILACS | ID: biblio-890692

RESUMEN

OBJECTIVE: To investigate the impact of the baseline status of patients with hepatitis B virus-associated acute-on-chronic liver failure on short-term outcomes. METHODS: A retrospective study was conducted that included a total of 138 patients with hepatitis B virus-associated acute-on-chronic liver failure admitted to the Department of Infectious Diseases, Taihe Hospital, Hubei University of Medicine, from November 2013 to October 2016. The patients were divided into a poor prognosis group (74 patients) and a good prognosis group (64 patients) based on the disease outcome. General information, clinical indicators and prognostic scores of the patients' baseline status were analyzed, and a prediction model was established accordingly. RESULTS: Elder age, treatment with artificial liver support systems and the frequency of such treatments, high levels of white blood cells, neutrophils, neutrophil count/lymphocyte count ratio, alanine aminotransferase, gamma-glutamyl transferase, total bilirubin, urea, and prognostic scores as well as low levels of albumin and sodium were all significantly associated with the short-term outcomes of hepatitis B virus-associated acute-on-chronic liver failure. The predictive model showed that logit (p) = 3.068 + 1.003 × neutrophil count/lymphocyte count ratio - 0.892 × gamma-glutamyl transferase - 1.138 × albumin - 1.364 × sodium + 1.651 × artificial liver support therapy. CONCLUSION: The neutrophil count/lymphocyte count ratio and serum levels of gamma-glutamyl transferase, albumin and sodium were independent risk factors predicting short-term outcomes of hepatitis B virus-associated acute-on-chronic liver failure, and the administration of multiple treatments with artificial liver support therapy during the early stage is conducive to improved short-term outcomes.


Asunto(s)
Humanos , Masculino , Femenino , Adulto , Persona de Mediana Edad , Insuficiencia Hepática Crónica Agudizada/virología , Hepatitis B/complicaciones , Pronóstico , Valor Predictivo de las Pruebas , Estudios Retrospectivos , Factores de Riesgo , Sensibilidad y Especificidad , Insuficiencia Hepática Crónica Agudizada/mortalidad , Insuficiencia Hepática Crónica Agudizada/sangre , Insuficiencia Hepática Crónica Agudizada/terapia , Hepatitis B/mortalidad , Hepatitis B/sangre , Hepatitis B/terapia
17.
Int J Clin Exp Med ; 8(11): 20876-82, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26885013

RESUMEN

OBJECTIVES: The aim of this study was to assess the effects of FibroScan, aspartate aminotransferase and alanine aminotransferase ratio (AAR), aspartate aminotransferase to platelet ratio index (APRI), fibrosis index based on the 4 factor (FIB-4) and their combinations on liver fibrosis in patients with hepatitis B. METHODS: 406 hospitalized patients with chronic hepatitis B (CHB) and cirrhosis in our hospital were analyzed retrospectively and collected patients clinical indicators, including liver stiffness (LS), AAR, APRI and FIB-4, and then compared the differences of these indicators between CHB group and hepatitis B with cirrhosis group. Receiver operating curve (ROC) was used to evaluate the differentiating capacity of these indicators on CHB and liver cirrhosis. RESULTS: Four indicators related to liver cirrhosis had a statistical significance between two groups (P < 0.01); the under ROC curve areas of LS, AAR, APRI and FIB-4 for differential diagnosis of CHB and liver cirrhosis were 0.866, 0.772, 0.632 and 0.885, respectively. The under ROC curve areas of LS, AAR, APRI and FIB-4 for differential diagnosis of liver cirrhosis at compensatory stage and de-compensatory stage were 0.627, 0.666, 0.795 and 0.820, respectively. CONCLUSION: LS, AAR, APRI and FIB-4 were good indicators as clinical diagnosis and differential diagnosis on hepatitis B related cirrhosis.

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