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1.
Sci Total Environ ; 923: 171424, 2024 May 01.
Article En | MEDLINE | ID: mdl-38432375

Extreme aerosol pollution poses significant risks to the climate, environment, and human health. To investigate the formation and impacts of aerosol pollution extreme events (APEE), the reanalysis product presents meticulous spatiotemporal information on the three-dimensional distribution of aerosols. However, there is a lack of comprehensive evaluation and information regarding the data quality of reanalysis products employed in APEE research, as well as limited understanding of their spatial and temporal distribution, variation, and long-term trends. To address this scientific gap, we conducted a global study for distribution and variation patterns of APEE using two widely-used reanalysis products, MERRA-2 (Modern-Era Retrospective Analysis for Research-2) and CAMS (Copernicus Atmospheric Monitoring Service). The APEE was defined here as a day when the daily aerosol optical depth (AOD) exceeding its 90th percentile for a given station and month. Eleven distinct land regions worldwide were selected for evaluation by comparing both reanalysis products with MODIS satellite products and ground-based observations in terms of frequency, intensity, and temporal trends of APEE. The analysis indicates that MERRA-2 and CAMS exhibit high matching rates (70 % and 80 %, respectively) in terms of occurrence timeline for APEE at monthly and seasonal scales, while also exhibiting strong monthly correlation coefficients (>0.65) with ground-based observations over selected regions. The total AOD (-0.002 âˆ¼ -0.123 decade-1), APEE AOD (-0.004 âˆ¼ -0.293 decade-1), and APEE frequency (-0.264 âˆ¼ -1.769 day month-1 decade-1) of both observations and reanalysis products in most regions showed a decreasing trend with various magnitude, except for some regions such as South Asia where the trend is increasing. Based on the aforementioned evaluation, it is evident that reanalysis products are effective and useful in identifying the temporal trends associated with APEE.

2.
Front Plant Sci ; 12: 704618, 2021.
Article En | MEDLINE | ID: mdl-34646282

Phototropins, namely, phototropin 1 (phot1) and phototropin 2 (phot2), mediate chloroplast movement to maximize photosynthetic efficiency and prevent photodamage in plants. Phot1 primarily functions in chloroplast accumulation process, whereas phot2 mediates both chloroplast avoidance and accumulation responses. The avoidance response of phot2-mediated chloroplasts under high-intensity blue light (HBL) limited the understanding of the function of phot1 in the chloroplast accumulation process at the HBL condition. In this study, we showed that the phot2 mutant exhibits a chloroplast accumulation response under HBL, which is defective when the root phototropism 2 (RPT2) gene is mutated in the phot2 background, mimicking the phenotype of the phot1 phot2 double mutant. A further analysis revealed that the expression of RPT2 was induced by HBL and the overexpression of RPT2 could partially enhance the chloroplast accumulation response under HBL. These results confirmed that RPT2 also participates in regulating the phot1-mediated chloroplast accumulation response under HBL. In contrast, RPT2 functions redundantly with neural retina leucine zipper (NRL) protein for chloroplast movement 1 (NCH1) under low-light irradiation. In addition, no chloroplast accumulation response was detected in the phot2 jac1 double mutant under HBL, which has been previously observed in phot2 rpt2 and phot1 phot2 double mutants. Taken together, our results indicated that phot1 mediates the HBL-induced chloroplast accumulation response in an RPT2-dependent manner and is also regulated by j-domain protein required for chloroplast accumulation response 1 (JAC1).

3.
Front Immunol ; 12: 681748, 2021.
Article En | MEDLINE | ID: mdl-34093584

Kidney macrophages are central in kidney disease pathogenesis and have therapeutic potential in preventing tissue injury and fibrosis. Recent studies highlighted that kidney macrophages are notably heterogeneous immune cells that fulfill opposing functions such as clearing deposited pathogens, maintaining immune tolerance, initiating and regulating inflammatory responses, promoting kidney fibrosis, and degrading the extracellular matrix. Macrophage origins can partially explain macrophage heterogeneity in the kidneys. Circulating Ly6C+ monocytes are recruited to inflammatory sites by chemokines, while self-renewed kidney resident macrophages contribute to kidney repair and fibrosis. The proliferation of resident macrophages or infiltrating monocytes provides an alternative explanation of macrophage accumulation after kidney injury. In addition, dynamic Ly6C expression on infiltrating monocytes accompanies functional changes in handling kidney inflammation and fibrosis. Mechanisms underlying kidney macrophage heterogeneity, either by recruiting monocyte subpopulations, regulating macrophage polarization, or impacting distinctive macrophage functions, may help develop macrophage-targeted therapies for kidney diseases.


Kidney Diseases/etiology , Kidney Diseases/metabolism , Macrophages/immunology , Macrophages/metabolism , Animals , Biomarkers , Cell Plasticity/immunology , Disease Susceptibility , Fibrosis , High-Throughput Nucleotide Sequencing , Humans , Kidney Diseases/pathology , Monocytes/immunology , Monocytes/metabolism , Organ Specificity/immunology , Single-Cell Analysis
4.
J Exp Bot ; 72(18): 6365-6381, 2021 09 30.
Article En | MEDLINE | ID: mdl-34145440

Hypocotyl phototropism is mediated by the phototropins and plays a critical role in seedling morphogenesis by optimizing growth orientation. However, the mechanisms by which phototropism influences morphogenesis require additional study, especially for polyploid crops such as cotton. Here, we found that hypocotyl phototropism was weaker in Gossypium arboreum than in G. raimondii (two diploid cotton species), and LC-MS analysis indicated that G. arboreum hypocotyls had a higher content of abscisic acid (ABA) and a lower content of indole-3-acetic acid (IAA) and bioactive gibberellins (GAs). Consistently, the expression of ABA2, AAO3, and GA2OX1 was higher in G. arboreum than in G. raimondii, and that of GA3OX was lower; these changes promoted ABA synthesis and the transformation of active GA to inactive GA. Higher concentrations of ABA inhibited the asymmetric distribution of IAA across the hypocotyl and blocked the phototropic curvature of G. raimondii. Application of IAA or GA3 to the shaded and illuminated sides of the hypocotyl enhanced and inhibited phototropic curvature, respectively, in G. arboreum. The application of IAA, but not GA, to one side of the hypocotyl caused hypocotyl curvature in the dark. These results indicate that the asymmetric distribution of IAA promotes phototropic growth, and the weakened phototropic curvature of G. arboreum may be attributed to its higher ABA concentrations that inhibit the action of auxin, which is regulated by GA signaling.


Hypocotyl , Phototropism , Abscisic Acid , Gossypium/genetics , Indoleacetic Acids
5.
Front Vet Sci ; 6: 228, 2019.
Article En | MEDLINE | ID: mdl-31355216

Babesia microti, an intraerythrocytic protozoa, can cause an emerging tick-borne disease-Human babesiosis. The parasite can successfully invade host red blood cells owing to the assistance of molecules expressed by babesia. Glyceraldehyde-3-phosphate dehydrogenase (GAPDH), the housekeeping intracellular glycolytic enzyme, can also be expressed in the external of cells, where contributes to binding to several molecules such as plasminogen and actin. In the present study, we identified B. microti GAPDH (BmGAPDH) and generated the recombinant BmGAPDH (rBmGAPDH) via an E. coli expression system. Furthermore, we confirmed its catalytic dehydration activity in vitro. Moreover, we also demonstrated that rBmGAPDH could bind to human plasminogen and mouse α-actin. In addition, we demonstrated that rBmGAPDH could recognize anti-B. microti mouse serum. In conclusion, BmGAPDH is a multifunctional glycolytic enzyme, which can bind to host plasminogen and α-actin.

6.
Parasitol Res ; 118(4): 1103-1112, 2019 Apr.
Article En | MEDLINE | ID: mdl-30770979

Human babesiosis, a worldwide emerging tick-borne disease, is caused by the intraerythrocytic apicomplexan parasite, babesia. In recent years, the number of infected patients globally has continued to rise, and thus human babesiosis poses a significant public health threat. Therefore, stronger initiatives should be undertaken to prevent further spread and development of this disease. In the present review, we summarize the epidemiology of reported human babesiosis cases in China from 1993 until now. The data show that Babesia microti is the dominant species causing human babesiosis in China and has led to more than 100 human infections thus far, where Babesia crassa-like is the second-most common. Moreover, Guangxi province is the second-most infected area after the Heilongjiang province. We also review the babesia life cycle, manifestation, diagnosis, and treatment. Additionally, we discuss babesiosis prevention strategies to raise public awareness, and also provide suggestions for improved babesiosis control.


Babesia microti/isolation & purification , Babesiosis , Tick-Borne Diseases/epidemiology , Animals , Babesiosis/diagnosis , Babesiosis/drug therapy , Babesiosis/epidemiology , Babesiosis/prevention & control , China/epidemiology , Geography , Humans , Life Cycle Stages , Mice , Tick-Borne Diseases/parasitology , Ticks/parasitology
7.
Biochem Biophys Res Commun ; 505(3): 761-767, 2018 11 02.
Article En | MEDLINE | ID: mdl-30293685

Development of an effective and safe anti-cancer drug is an urgent request for hepatocellular carcinoma (HCC). In this study, we synthesized a series of novel indole substituted dihydropyrido[2,3-d]pyrimidines through the multicomponent reactions to connect pyrido[2,3-d]pyrimidine and indole moities via an one-pot three-component reaction of 3-cyanoacetyl indoles 1, various aromatic aldehyde 2, and 2,6-diaminopyrimidin-4(3H)-one 3. Subsequently, we screened their cytotoxicity via CCK-8 assay in HepG2 cells, a human hepatoma cell line and chose compound 4p that showed the lowest dosage of IC50 to study the antitumor activities to HCC. Interestingly, 4p significantly induced the cell cycle arrest and apoptosis of HepG2 via targeting AKT and ERK1/2 signaling pathways in vitro. To improve the solubility of compound 4p, we hosted this compound into the substituted glucopyranose ring of (2-Hydroxypropyl)-ß-cyclodextrin (HBC), a cosolvent approved by FDA with the help of ultrasonication and heating. Finally, we showed that oral administration of HBC-hosted 4p effectively inhibited tumor growth and prolonged the survival time of tumor-bearing mice in subcutaneously xenografted model. These results suggest that multicomponent reactions connecting pyrido[2,3-d]pyrimidine and indole moities is a productive and economical method for the synthesis of anticancer compound, and oral administration of HBC-hosted 4p is an effective and safe agents for treatment of HCC, whose clinical application potency warrant further studies.


Antineoplastic Agents/pharmacology , Carcinoma, Hepatocellular/drug therapy , Liver Neoplasms/drug therapy , MAP Kinase Signaling System/drug effects , Proto-Oncogene Proteins c-akt/antagonists & inhibitors , Xenograft Model Antitumor Assays , Administration, Oral , Animals , Antineoplastic Agents/administration & dosage , Antineoplastic Agents/chemistry , Carcinoma, Hepatocellular/metabolism , Cell Line , Cell Line, Tumor , Cell Survival/drug effects , Female , Hep G2 Cells , Humans , Indoles/chemistry , Liver Neoplasms/metabolism , Mice, Inbred BALB C , Mice, Nude , Molecular Structure , Proto-Oncogene Proteins c-akt/metabolism , Pyrimidines/chemistry , Tumor Burden/drug effects
8.
Future Oncol ; 14(15): 1511-1520, 2018 Jun.
Article En | MEDLINE | ID: mdl-29380639

Quinacrine (QC), a synthetic antimalarial drug, was consistently used worldwide to combat malaria during the last century. Interestingly, later studies revealed that it also displays various additional properties, specifically antitumor activity. QC's antitumor activity occurs via a variety of pathways, including DNA intercalation, angiogenesis inhibition, signal transduction regulation, cell cycle arrest and autophagy induction. In combination with traditional therapies such as chemotherapy and radiotherapy, QC has also displayed synergistic effects against tumors, which may open promising therapeutic avenues. However, the breadth and complexity of its antitumor mechanisms have not yet been fully elucidated. In this review, we have systematically categorized QC's reported antitumor mechanisms from recent studies, to enable a deeper understanding of its antitumor activity.


Antimalarials/therapeutic use , Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Neoplasms/therapy , Neovascularization, Pathologic/drug therapy , Quinacrine/therapeutic use , Animals , Antimalarials/pharmacology , Antineoplastic Combined Chemotherapy Protocols/pharmacology , Apoptosis/drug effects , Autophagy/drug effects , Cell Cycle Checkpoints/drug effects , Combined Modality Therapy/methods , Drug Synergism , Humans , Neoplasms/pathology , Neovascularization, Pathologic/pathology , Off-Label Use , Quinacrine/pharmacology , Signal Transduction/drug effects
9.
Proc Natl Acad Sci U S A ; 110(48): E4581-90, 2013 Nov 26.
Article En | MEDLINE | ID: mdl-24218569

Deep convective clouds (DCCs) play a crucial role in the general circulation, energy, and hydrological cycle of our climate system. Aerosol particles can influence DCCs by altering cloud properties, precipitation regimes, and radiation balance. Previous studies reported both invigoration and suppression of DCCs by aerosols, but few were concerned with the whole life cycle of DCC. By conducting multiple monthlong cloud-resolving simulations with spectral-bin cloud microphysics that capture the observed macrophysical and microphysical properties of summer convective clouds and precipitation in the tropics and midlatitudes, this study provides a comprehensive view of how aerosols affect cloud cover, cloud top height, and radiative forcing. We found that although the widely accepted theory of DCC invigoration due to aerosol's thermodynamic effect (additional latent heat release from freezing of greater amount of cloud water) may work during the growing stage, it is microphysical effect influenced by aerosols that drives the dramatic increase in cloud cover, cloud top height, and cloud thickness at the mature and dissipation stages by inducing larger amounts of smaller but longer-lasting ice particles in the stratiform/anvils of DCCs, even when thermodynamic invigoration of convection is absent. The thermodynamic invigoration effect contributes up to ~27% of total increase in cloud cover. The overall aerosol indirect effect is an atmospheric radiative warming (3-5 W m(-2)) and a surface cooling (-5 to -8 W m(-2)). The modeling findings are confirmed by the analyses of ample measurements made at three sites of distinctly different environments.


Aerosols/chemistry , Air Movements , Atmosphere/chemistry , Convection , Models, Theoretical , Steam/analysis , Computer Simulation , Thermodynamics
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