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1.
Huan Jing Ke Xue ; 43(1): 46-60, 2022 Jan 08.
Artigo em Chinês | MEDLINE | ID: mdl-34989489

RESUMO

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.


Assuntos
Poluentes Atmosféricos , Aerossóis/análise , Poluentes Atmosféricos/análise , Pequim , China , Monitoramento Ambiental , Material Particulado/análise , Estações do Ano
2.
Sci Total Environ ; 803: 149857, 2022 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-34496345

RESUMO

Owing to the local characteristics of stable nitrogen isotopes in nitrogen oxides (δ15N-NOx) emitted from biomass burning, the lack of data on δ15N-NOx values associated with biomass burning in China limits the use of this parameter in identifying and quantifying the sources of atmospheric nitrate (NO3-) and NOx. The results showed that the δ15N-NOx values of open burning and rural cooking stoves in China ranged from -3.7‰ to 3.1‰ and -11.9‰ to 1.5‰, respectively. The δ15N values of nine biomass fuel sources (δ15N-biomass) ranged from 0.1‰ to 4.1‰. Significant linear relationships between the δ15N-biomass values and δ15N-NOx values of open burning (δ15N-NOx = 1.1δ15N-biomass - 2.7; r2 = 0.63; p < 0.05) and rural cooking stoves (δ15N-NOx = 1.7δ15N-biomass - 9.8; r2 = 0.72; p < 0.01) suggested that the variations in δ15N-NOx values from biomass burning were mainly controlled by the biomass fuel source. The isotopic fractionation of nitrogen during the biomass burning process might have led to the higher δ15N-NOx values from open burning in comparison to rural cooking stoves. By combining the δ15N-NOx values of biomass burning with biomass burning emission inventory data, a model for calculating the δ15N-NOx values of biomass burning in different regions of China was established, and the estimated δ15N-NOx value of biomass burning at the national scale was -0.8 ± 1.2‰. But the limited δ15N-biomass values increase the uncertainty of model in national scale.


Assuntos
Poluentes Atmosféricos , Nitrogênio , Poluentes Atmosféricos/análise , Biomassa , China , Monitoramento Ambiental , Isótopos de Nitrogênio/análise
3.
Int J Gen Med ; 14: 9203-9209, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34880659

RESUMO

Background: Reactive oxygen species (ROS) generated by NADPH oxidase has a pivotal role in the nonspecific innate immune response to invading microorganisms including M. tuberculosis (MTB). NCF2 and NOX2 were considered as important functional subunits of NADPH oxidase complex; hence, this study aimed to evaluate the NCF2, NOX2 mRNA expressions in PBMC of pulmonary tuberculosis (PTB) patients. Methods: A total of 79 PTB patients and 73 controls were included in our study. Quantitative real-time reverse transcription polymerase chain reaction (qRT-PCR) was used to measure the NCF2, NOX2 mRNA levels, and receiver operating characteristic (ROC) curve analysis was performed to assess the diagnostic value of NCF2, NOX2 in PTB patients. Results: When compared to controls, the NCF2, NOX2 mRNA levels were significantly increased in PBMC from PTB patients (P < 0.001). However, the NCF2, NOX2 mRNA levels were not associated with major clinical and laboratory data of PTB patients. Area under curve (AUC) of ROC curve analysis for NCF2 and NOX2 were 0.686 (95% CI: 0.601, 0.770) and 0.705 (95% CI: 0.623, 0.787), respectively. Conclusion: Altered NCF2, NOX2 mRNA levels in PTB patients implied that these genes might play roles in PTB, and their expression levels might be potential biomarkers for the diagnosis of PTB.

4.
Eur J Med Chem ; 228: 114030, 2021 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-34883292

RESUMO

The epidemic coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has now spread worldwide and efficacious therapeutics are urgently needed. 3-Chymotrypsin-like cysteine protease (3CLpro) is an indispensable protein in viral replication and represents an attractive drug target for fighting COVID-19. Herein, we report the discovery of 9,10-dihydrophenanthrene derivatives as non-peptidomimetic and non-covalent inhibitors of the SARS-CoV-2 3CLpro. The structure-activity relationships of 9,10-dihydrophenanthrenes as SARS-CoV-2 3CLpro inhibitors have carefully been investigated and discussed in this study. Among all tested 9,10-dihydrophenanthrene derivatives, C1 and C2 display the most potent SARS-CoV-2 3CLpro inhibition activity, with IC50 values of 1.55 ± 0.21 µM and 1.81 ± 0.17 µM, respectively. Further enzyme kinetics assays show that these two compounds dose-dependently inhibit SARS-CoV-2 3CLprovia a mixed-inhibition manner. Molecular docking simulations reveal the binding modes of C1 in the dimer interface and substrate-binding pocket of the target. In addition, C1 shows outstanding metabolic stability in the gastrointestinal tract, human plasma, and human liver microsome, suggesting that this agent has the potential to be developed as an orally administrated SARS-CoV-2 3CLpro inhibitor.

5.
Front Immunol ; 12: 731565, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34925313

RESUMO

Abnormal vitamin D metabolism is involved in the pathogenesis of rheumatoid arthritis (RA). In this study, we evaluated the association of single nucleotide polymorphisms (SNPs) and methylation levels in vitamin D metabolic pathway genes with RA susceptibility. Ten SNPs in vitamin D metabolic pathway genes (CYP2R1, CYP24A1, VDR, CYP27B1) were genotyped in 477 RA patients and 496 controls by improved multiple ligase detection reaction (iMLDR). The methylation levels of the promoter regions of these genes were detected in 122 RA patients and 123 controls using Illumina Hiseq platform. We found that the CYP2R1 rs1993116 GA genotype, CYP27B1 rs4646536 GA genotype, rs4646536 A allele frequencies were significantly increased in RA patients when compared to controls. The decreased risk of rs1993116, rs4646536 was found under the dominant mode in RA patients. However, no significant association was found between CYP2R1 rs7936142, rs12794714, CYP24A1 rs2762934, rs6068816, rs2296239, rs2296241, VDR rs11574129, rs3847987 polymorphism, and RA susceptibility. The VDR, CYP27B1 methylation levels in RA patients were significantly lower than those in controls, while CYP2R1, CYP24A1 methylation levels were not associated with RA. There were no statistical associations between CYP2R1, CYP24A1, VDR, CYP27B1 methylation levels and their respective genotype in RA patients. In addition, plasma 25OHD level in RA patients was significantly lower than that in healthy controls. In summary, our results showed that CYP2R1, CYP27B1 genetic variations were associated with the genetic background of RA, while altered VDR, CYP27B1 methylation levels were related to the risk of RA.

6.
Zhongguo Dang Dai Er Ke Za Zhi ; 23(12): 1289-1294, 2021 Dec 15.
Artigo em Inglês, Chinês | MEDLINE | ID: mdl-34911615

RESUMO

OBJECTIVES: To study the role of the low-density lipoprotein receptor-related protein 1 (LRP1)-proline-rich tyrosine kinase 2 phosphorylation (pPyk2)-matrix metalloproteinases 9 (MMP9) pathway in hyperoxia-induced lung injury in neonatal rats. METHODS: A total of 16 neonatal rats were randomly placed in chambers containing room air (air group) or 95% medical oxygen (hyperoxia group) immediately after birth, with 8 rats in each group. All of the rats were sacrificed on day 8 of life. Hematoxylin and eosin staining was used to observe the pathological changes of lung tissue. ELISA was used to measure the levels of soluble LRP1 (sLRP1) and MMP9 in serum and bronchoalveolar lavage fluid (BALF). Western blot was used to measure the protein expression levels of LRP1, MMP9, Pyk2, and pPyk2 in lung tissue. RT-PCR was used to measure the mRNA expression levels of LRP1 and MMP9 in lung tissue. RESULTS: The hyperoxia group had significantly higher levels of sLRP1 and MMP9 in serum and BALF than the air group (P<0.05). Compared with the air group, the hyperoxia group had significant increases in the protein expression levels of LRP1, MMP9, and pPyk2 in lung tissue (P<0.05). The hyperoxia group had significantly higher relative mRNA expression levels of LRP1 and MMP9 in lung tissue than the air group (P<0.05). CONCLUSIONS: The activation of the LRP1-pPyk2-MMP9 pathway is enhanced in hyperoxia-induced lung injury in neonatal rats, which may be involved in the pathogenesis of bronchopulmonary dysplasia.


Assuntos
Hiperóxia , Lesão Pulmonar , Animais , Animais Recém-Nascidos , Hiperóxia/complicações , Pulmão , Lesão Pulmonar/etiologia , Metaloproteinase 9 da Matriz/genética , Ratos
7.
Huan Jing Ke Xue ; 42(11): 5109-5121, 2021 Nov 08.
Artigo em Chinês | MEDLINE | ID: mdl-34708950

RESUMO

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.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , COVID-19 , Poluentes Ambientais , Aerossóis/análise , Poluentes Atmosféricos/análise , Poluição do Ar/análise , Pequim , China , Controle de Doenças Transmissíveis , Monitoramento Ambiental , Humanos , Material Particulado/análise , SARS-CoV-2 , Estações do Ano
8.
Clin Lab ; 67(10)2021 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-34655210

RESUMO

BACKGROUND: CD14 is a pattern recognition receptor constitutively expressed in different types of immune cells, either in a membrane-anchored (mCD14) or in a soluble (sCD14) form. This study investigated whether hepatic CD14 expression levels were correlated with the grades of liver inflammation as well as the potential usefulness of serum sCD14 as a biomarker for predicting liver inflammation in chronic hepatitis B (CHB) patients with normal or mildly elevated ALT. METHODS: A total of 216 treatment-naive CHB patients with normal or mildly elevated ALT who underwent liver biopsy were recruited. Hepatic expression level of CD14 was measured using immunohistochemistry and real-time PCR. Serum sCD14 concentrations were determined with an enzyme-linked immunosorbent assay. Correlations between hepatic CD14, serum sCD14, and liver inflammation grade were analyzed. Univariate and multivariate analysis were performed to identify significant liver inflammation-associated factors. The receiver operating characteristic curve was used to assess the discriminating power of serum sCD14 to significant liver inflammation in CHB patients with normal or mildly elevated ALT. RESULTS: Both hepatic expression levels of CD14 and serum sCD14 concentrations significantly increased with the aggravation of liver inflammation. Moreover, hepatic expression levels of CD14, serum sCD14 concentrations, and liver inflammation grades were positively correlated with each other. Three parameters including alkaline phosphatase (ALP), neutrophil, and sCD14 were identified as independent predictors of significant liver inflammation. Subsequently, a diagnostic equation named model-sCD14 was developed incorporating sCD14 and other variables (ALP and neutrophils) with p < 0.05 in multivariate logistic analysis. The area under receiver operating characteristic curve (AUC) of sCD14 for predicting significant liver inflammation was 0.788 and the optimal cutoff was 27.14 ng/mL, with a sensitivity of 66.67%, a specificity of 81.70%, positive predictive value of 60.01%, and negative predictive value of 85.62%. When sCD14 was replaced by model-sCD14, the AUC value increased from 0.788 to 0.843 (z = 2.311, p = 0.021), with sensitivity of 77.78%, specificity of 77.12%, positive predictive value of 58.33%, and negative predictive value of 89.39%. CONCLUSIONS: Serum sCD4 has the potential to discriminate significant liver inflammation from CHB patients with normal or mildly increased ALT levels.


Assuntos
Hepatite B Crônica , Receptores de Lipopolissacarídeos , Alanina Transaminase , Biomarcadores , Hepatite B Crônica/diagnóstico , Humanos , Inflamação/diagnóstico , Fígado
9.
J Coll Physicians Surg Pak ; 31(11): 1268-1272, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34689481

RESUMO

OBJECTIVE: To investigate the clinical safety and electrocardiogram (ECG) characteristics in patients with left bundle branch area pacing (LBBAP). STUDY DESIGN: Retrospective study. PLACE AND DURATION OF STUDY: Department of Cardiology, The First Affiliated Hospital of Bengbu Medical College, Bengbu, China, from May 2018 to January 2020. METHODOLOGY: Patients scheduled for Left Bandle Branch Area Pacing (LBBAP), who were admitted due to bradycardia, had been prospectively recruited. The Medtronic 3830 pacing lead was first placed at the right ventricular (RV) side of the interventricular septum (IVS) with pacing parameters (pacing threshold, pacing impedance and sensing amplitude) and ECG characteristics [QRS morphology, paced QRS duration and stimulus to peak left ventricular activation time (Sti-LVAT)] measured, which was called the right ventricular septum pacing group (RVSP). Then the pacing lead was screwed towards the left ventricular (LV) side of the IVS; and the corresponding parameters and ECG characteristics were assessed, which was called LBBAP group. RESULTS: RVSP caused left bundle block (LBBB) morphology on ECG, while pacing at left bundle area led to right bundle branch block (RBBB) morphology, without remarkable difference in pacing threshold and pacing impedance. The sensing amplitude during LBBAP was significantly higher compared with RVSP (p <0.05). QRS duration and Sti-LVAT were significantly shorter when paced on LBBAP compared with RVSP (p <0.05). Patients with LBBB morphology in intrinsic rhythm showed the greatest reduction in paced QRS duration and Sti-LVAT compared to patients with RBBB morphology or no bundle branch block morphology (p <0.001). There were no complications during pacemaker implantation and no adverse events observed during follow-up. The pacing parameters remained stable during the follow-up (9.2 ± 3.7 months). CONCLUSION: Compared with pacing on RVSP, patients with LBBAP showed RBBB morphology with significantly reduced QRS duration and LV Sti-LVAT under similar pacing parameters. LBBAP is safe and feasible and may be a promising strategy for patients with LBBB morphology who are indicated for ventricular pacing. Key Words: Physiological pacing, Left bundle branch pacing, Right ventricular pacing, Left bundle branch block, Pacemaker.


Assuntos
Bloqueio de Ramo , Septo Interventricular , Bloqueio de Ramo/terapia , Estimulação Cardíaca Artificial , Eletrocardiografia , Humanos , Estudos Retrospectivos
10.
Org Lett ; 23(19): 7336-7341, 2021 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-34523943

RESUMO

Exploration of the diastereodivergent synthesis of spirocyclic oxindoles has been challenging. Herein we report asymmetric [3 + 2] annulations of isatin-derived Morita-Baylis-Hillman (MBH) carbonates and 5-alkenylthiazol-4(5H)-ones. Interestingly, two different chiral catalysts, amide-phosphine and 4-dimethylaminopyridine (DMAP)-thiourea, could lead to two kinds of diastereomeric dispiro oxindoles with three contiguous stereogenic centers. The hexafluoroisopropanol (HFIP) additive plays a vital role in accelerating the reaction and tuning the diastereoselectivity. Moreover, both annulation adducts could be further converted to structurally diverse spirooxindoles.

11.
Chem Commun (Camb) ; 57(76): 9724-9727, 2021 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-34474456

RESUMO

A diastereo- and enantioselective rhodium(III)-catalyzed reductive cyclization of cyclohexadienone-tethered terminal alkenes and (E)-1,2-disubstituted alkenes (1,6-dienes) is reported, providing cis-bicyclic products bearing three contiguous stereocenters with good yields and high diastereo- and enantioselectivities. The kinetic resolution of the racemic precursor is also achieved with good efficiency. Moreover, a subgram-scale experiment, several transformations of the cyclization product, and one-pot preparation of bridged polycyclic frameworks are presented.

12.
J Clin Pathol ; 2021 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-34281957

RESUMO

AIMS: S-phase kinase-associated protein 2 (Skp2) oncoprotein is overexpressed in a variety of cancer tissues and promotes the malignant development of cancer. The expression levels of chromobox homolog 7 (CBX7) protein are varied among different types of cancer tissues, but its role in cervical cancer is not clear. We aimed to examine the expression and clinical significance of Skp2 and CBX7 proteins as well as their correlations in cervical cancer. METHODS: Immunohistochemistry was used to detect the expression of Skp2 and CBX7 proteins in the cancerous tissues and adjacent tissues of 64 patients with cervical cancer. Relevant clinicopathological data of these patients were collected, compared and analysed for the correlations. RESULTS: The expression of Skp2 protein in cervical cancer (87.5%) was higher than that in paracancerous tissues (14.1%), and the expression was positively correlated with clinical stage, malignant degree, lymphatic metastasis, vascular invasion and interstitial invasion. The expression of CBX7 protein in cervical cancer (48.4%) was lower than that in paracancerous tissues (96.8%), and the expression was negatively correlated with clinical stage, malignant degree, interstitial invasion, vascular invasion and lymphatic metastasis. The expression of Skp2 protein and CBX7 protein in cervical cancer tissues and adjacent tissues was negatively correlated. The expression of Skp2 and CBX7 proteins was closely related to the clinicopathological features of cervical cancer. CONCLUSIONS: CBX7 may play the role of a tumour suppressor gene in cervical cancer and provide reference value for the diagnosis and new targeted treatment of cervical cancer.

13.
Reprod Biol ; 21(3): 100510, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33993032

RESUMO

Recurrent miscarriage (RM) occurs in approximately 1% of all couples trying to conceive. Most of the research about recurrent miscarriage mainly focuses on immunology. However, the roles of microRNAs plays (miRNAs) in RM remain elusive. Here, the function of miR-155-5p in regulating survival of human decidua stromal cells through NF-κB signaling was explored in RM. The quantitative real-time polymerase chain reaction (qRT-PCR) results showed that miR-155-5p was downregulated in both decidua tissues and serum from RM patients. While, the ELISA assay revealed that the overexpression of miR-155-5p reduced the inflammatory cytokines secretion including IL-6, IFN-γ, TNF-α and IL-10 in decidua stromal cells. The results of cell counting Kit8 (CCK-8) and immunofluorescence experiments suggested that transfection of miR-155-5p into decidua stromal cells can promote the growth and proliferation of cells. In addition, overexpression of miR-155-5p can also inhibit the apoptosis of decidua stromal cells. The western blot assay results demonstrated that the miR-155-5p exerted effect mainly through activating NF-κB signaling pathway in RM. In conclusion, the miRNA-155-5p can not only promote the growth and proliferation but also inhibit the apoptosis of decidua stromal cells depending on inhibiting NF-κB signaling pathway in recurrent miscarriage.

14.
Chemosphere ; 281: 130773, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34000656

RESUMO

Improving accumulation of heavy metals (HMs) by plants is an important pathway for constructed wetland (CW) to alleviate the environmental risks caused by their release. This study aims to regulate HMs (Cr, Ni, Cu, Zn, and Cd) accumulated by Acorus calamus L. in the sandy substrate CW with different nitrogen forms, including ammonia (NH4+), nitrate (NO3‾), and NH4+/NO3‾ (1:1) in synthetic tailwaters. In general, the removal efficiency of HMs by CW could reach 92.4% under the initial concentrations below 500 µg/L. Accumulation percentages of HMs in the shoots and roots of plants in CW with NH4+ and NH4+/NO3‾ influents increased by 52-395% and 15-101%, respectively, when compared with that of NO3‾ treatment. Influents with NH4+ promoted plant growth of Acorus calamus L. and metabolic functions, such as carbohydrate metabolism/amino acid metabolism, related to HMs mobilization of rhizosphere bacterial communities, which might induce more organic acids and amino acids secreted by plants and microbes during their metabolic processes. These are the main reasons for the enhancive mobilization of HMs from their precipitation fractions and their uptake by plants in CW with NH4+ treatments. Moreover, the enhancement of organics secreted from plants and microbes also led to the high denitrification efficiency and nitrogen removal in CW. Overall, this study could provide a feasible method for the enhancive accumulation of HMs by wetland plants via the regulation water treatment process to appropriately increase NH4+ for CW.


Assuntos
Acorus , Metais Pesados , Purificação da Água , Nitrogênio , Áreas Alagadas
15.
Environ Sci Technol ; 55(9): 5677-5688, 2021 05 04.
Artigo em Inglês | MEDLINE | ID: mdl-33874721

RESUMO

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.


Assuntos
Poluentes Atmosféricos , Madeira , Aerossóis/análise , Poluentes Atmosféricos/análise , Atmosfera , Biomassa , Carbono , Fumaça , Fuligem/análise , Madeira/química
16.
Genes Nutr ; 16(1): 6, 2021 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-33882819

RESUMO

OBJECTIVE: This study aimed to evaluate the association of single nucleotide polymorphisms (SNPs) of vitamin D metabolic pathway genes with susceptibility to pulmonary tuberculosis (PTB). METHODS: Nine hundred seventy-nine patients (490 PTB cases and 489 healthy controls) were included in this study. Seventeen SNPs of vitamin D metabolic pathway genes, including CYP24A1, CYP27A1, CYP27B1, CYP2R1, GC, and DHCR7, were genotyped with improved multiple ligase detection reaction (iMLDR). RESULTS: The GC rs3733359 GA, rs16847024 CT genotypes were significantly associated with the reduced risk of PTB, and the rs3733359 A, rs16847024 T alleles were also associated with the decreased PTB susceptibility. The GT genotype of GC rs4588 variant was significantly higher in patients with PTB when compared to controls. Moreover, the increased risk of rs3733359 and rs16847024 variants, and a decreased risk of rs4588, were found under the dominant mode among the PTB patients. However, there was no significant relationship of CYP24A1, CYP27A1, CYP27B1, CYP2R1, and DHCR7 polymorphisms with the risk of PTB. In CYP27A1, the rs17470271 T and rs933994 T alleles were significantly associated with leukopenia, drug resistance in the PTB patients, respectively. In GC gene, the rs7041 and rs3733359 variants were found to be associated with pulmonary infection, fever in the PTB patients, respectively. The increased frequency of rs16847024 TT genotype was found in the PTB patients with fever and drug-induced liver damage. DHCR7 rs12785878 TT genotype, and T allele frequencies were both significantly associated with pulmonary infection in the PTB patients. The haplotype analysis showed that CYP24A1 TACT, CYP2R1 GGCT, GGAT, GC AATG haplotypes were related to PTB susceptibility. CONCLUSION: Our study suggested that GC SNPs were associated with the genetic background of PTB. CYP27A1, GC, and DHCR7 genetic variations might contribute to several clinical phenotypes of PTB in Chinese.

17.
Water Res ; 198: 117132, 2021 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-33878661

RESUMO

The interaction of As(III) with micron-sized, mechanochemically sulfidated zero-valent iron (S-mZVIbm) has been studied under both anoxic and oxic conditions. The As(III) removal capacity varied with the increase of S/Fe molar ratio under anoxic conditions, while it continuously decreased under oxic conditions. A series of sequential extractions, X-ray photoelectron spectroscopy (XPS) and X-ray absorption near edge structure (XANES) spectroscopy analyses were used to investigate As(III) removal mechanisms. In the absence of oxygen, As(III) was removed from solution primarily through the formation of As4S4 with less than half of the removal resulting from the adsorption of As(III)/As(V) and FeAsS precipitation. Under oxic conditions, adsorption onto iron (oxyhydr)oxides was the dominant mechanism of As(III) removal. Increasing sulfidation decreased particle Fe(0) content, which resulted in less production of iron (oxyhydr)oxides and therefore lower As(III) removal capacities. Column experiments showed that less than 2 wt% of S-mZVIbm in sand was able to rapidly reduce the As(III) concentration in a real groundwater from 300 to 10 µg/L, the Chinese drinking water standard, for up to 750 BV with an EBCT of 2.54 min. This study demonstrates that S-mZVIbm is an efficient and cost-effective material in treating As-contaminated water to ensure water safety.


Assuntos
Arsênio , Água Subterrânea , Poluentes Químicos da Água , Adsorção , Ferro
18.
Mol Med ; 27(1): 21, 2021 03 03.
Artigo em Inglês | MEDLINE | ID: mdl-33658002

RESUMO

BACKGROUND: Studies have found that circular RNAs (circRNAs) play key roles in cardiovascular diseases. However, the function of circROBO2 in acute myocardial infarction (AMI) is unclear. This study aimed to investigate the pathogenesis of circROBO2 in AMI. METHODS: qRT-PCR and Western blot were used to determine the expression levels of circROBO2, miR-1184, and TRADD in AMI and sham-operated mouse models at mRNA and protein level, respectively. The relationship among miR-1184, circROBO2 and TRADD was evaluated by RNA immunoprecipitation (RIP) analysis and luciferase reporter gene analysis. The roles of circROBO2, miR-1184, and TRADD in myocardial cell apoptosis were evaluated using flow cytometry. Ultrasound echocardiography, serum creatine kinase MB (CK-MB) and lactate dehydrogenase (LDH), myocardial infarction area, and myocardial cell apoptosis were measured to examine the effects of circROBO2 on myocardial injury. RESULTS: The expression levels of miR-1184 were significantly reduced, and the expression levels of circROBO2 and TRADD were significantly increased in MI group. CircROBO2 acted as a sponge for miR-1184 by upregulating the expression of TRADD. In addition, overexpression of miR-1184 enhanced the protective effect of knockdown of circROBO2 by partially inhibiting the expression of TRADD in vivo and in vitro. CONCLUSION: Knockdown of circROBO2 reduced the apoptosis of cardiomyocytes by increasing the expression levels of miR-1184, which in turn decreased the expression levels of TRADD in the myocardium post-MI.


Assuntos
MicroRNAs , Infarto do Miocárdio , RNA Circular , Proteína de Domínio de Morte Associada a Receptor de TNF , Animais , Apoptose/genética , Células Cultivadas , Masculino , Camundongos Endogâmicos C57BL , MicroRNAs/genética , MicroRNAs/metabolismo , Infarto do Miocárdio/genética , Infarto do Miocárdio/metabolismo , Miocárdio/metabolismo , Miócitos Cardíacos/metabolismo , RNA Circular/genética , RNA Circular/metabolismo , Proteína de Domínio de Morte Associada a Receptor de TNF/genética , Proteína de Domínio de Morte Associada a Receptor de TNF/metabolismo
19.
Eur J Med Chem ; 217: 113379, 2021 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-33756126

RESUMO

Emerging evidence suggests that cancer metabolism is closely associated to the serine biosynthesis pathway (SSP), in which glycolytic intermediate 3-phosphoglycerate is converted to serine through a three-step enzymatic transformation. As the rate-limiting enzyme in the first step of SSP, phosphoglycerate dehydrogenase (PHGDH) is overexpressed in various diseases, especially in cancer. Genetic knockdown or silencing of PHGDH exhibits obvious anti-tumor response both in vitro and in vivo, demonstrating that PHGDH is a promising drug target for cancer therapy. So far, several types of PHGDH inhibitors have been identified as a significant and newly emerging option for anticancer treatment. Herein, this comprehensive review summarizes the recent achievements of PHGDH, especially its critical role in cancer and the development of PHGDH inhibitors in drug discovery.


Assuntos
Antineoplásicos/farmacologia , Inibidores Enzimáticos/farmacologia , Neoplasias/tratamento farmacológico , Fosfoglicerato Desidrogenase/antagonistas & inibidores , Antineoplásicos/química , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Inibidores Enzimáticos/química , Humanos , Estrutura Molecular , Neoplasias/metabolismo , Fosfoglicerato Desidrogenase/química , Fosfoglicerato Desidrogenase/metabolismo , Estudos Retrospectivos
20.
Open Med (Wars) ; 16(1): 410-418, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33748425

RESUMO

The aim of this study was to evaluate the association of the chromobox homologue 7 (CBX7) expression with the epithelial-mesenchymal transition in cervical cancer (CC), as well as with the disease prognosis. CBX7, E-cadherin (E-cad), and vimentin (VIM) expression levels were detected with immunohistochemistry. The relationship between the expression of CBX7, E-cad, and VIM expression and conventional clinicopathological characteristics of CC were evaluated. The positive expression rates of CBX7 and E-cad in the CC tissues were lower than the adjacent non-tumorous cervical tissues. Moreover, the VIM expression level was higher. The CBX7 expression was positively correlated with the E-cad expression, whereas was negatively correlated with the VIM expression. Furthermore, CBX7 was associated with the disease clinical staging, histological differentiation, lymph node metastasis, and vascular invasion. Patients with negative CBX7 expression showed decreased overall survival rates compared with those with low or high CBX7 expression. Multivariate Cox regression analysis indicated that the decreased CBX7 expression was an independent predictor for the poor prognosis of CC. In conclusion, the absence of CBX7 is associated with the histologic differentiation, lymphatic metastasis, vascular invasion, and poor prognosis of CC. CBX7 may be an independent prognostic factor for the prognosis of CC patients.

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