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1.
Hum Gene Ther ; 2020 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-32024383

RESUMO

Refractoriness to conventional chemotherapy is a major challenge in the treatment of advanced ovarian cancer (OC). There is increasing evidence that mitochondrial priming correlates with cisplatin response in various cancers. Notably, Bim and Bid, two of the pro-apoptotic BH3-only proteins, are recognized as the most effective inducers of mitochondrial priming in OC. In this study, we constructed two tumor-specific oncolytic adenoviruses (Ads) coding for Bim (Ad-Bim) or truncated Bid (Ad-tBid), respectively, and performed gain-of-function assays in nine OC cell lines. Ad-tBid exhibited significant anti-tumor efficacy than the controls. On addition of Ad-tBid pretreatment, mito-primed cells displayed more sensitivity to cisplatin both in vitro and ex vivo. We also found that Ad-tBid induced mitochondrial apoptosis in a Bak-dependent manner. Furthermore, a combined cisplatin plus Ad-tBid therapy markedly inhibited tumor growth in a subcutaneous xenotransplanted tumor model. In mice bearing peritoneal disseminated OC, intraperitoneal administration of Ad-tBid potentiated the anti-tumor effect of cisplatin. Our findings suggest that Ad-tBid enhances cisplatin response in OC cells, establishing the potential treatment of advanced OC via a combination of cisplatin and Ad-tBid.

2.
Med Sci Monit ; 26: e921233, 2020 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-32032347

RESUMO

BACKGROUND Osteosarcoma is a common malignant tumor of musculoskeletal stromal cells. Osteosarcoma clinical behavior depends mostly on the histologic grade, the site of primary tumor, the response to chemotherapy, and the presence of pulmonary metastases. The aim of this study was to knockout SHOX CNE9/10 in U2OS osteosarcoma cells and to analyze the effects on cell growth and apoptosis. MATERIAL AND METHODS U2OS cells with CNE9 knockout and U2OS cells with CNE10 knockout were established via the CRISPR/Cas9 system. Sanger sequencing was used to detect the success of the knockdown experiment. Western blotting and quantitative polymerase chain reaction were used to detect the expression levels of short stature homeobox-containing gene (SHOX) protein and messenger RNA (mRNA) after knockdown of CNE9 and CNE10. The cell viability and apoptotic rate were detected by the Cell Counting Kit-8 method and by flow cytometry. RESULTS The Sanger sequencing results showed that the knockdown experiment was successful. The levels of SHOX mRNA and protein were significantly reduced after knocking down CNE9 and CNE10. Knockdown of CNE9 and CNE10 significantly increased the growth and inhibited the apoptosis of U2OS osteosarcoma cells. CNE9/CNE10 knockdown U2OS cells were successfully constructed. CONCLUSIONS Knockdown of CNE9 and CNE10 promoted U2OS cell growth and inhibited apoptosis by decreasing SHOX expression. This CNE9/CNE10 knockout U2OS cell model could provide a bridge for the research on SHOX and CNEs in osteosarcoma.

3.
Chin Med J (Engl) ; 2020 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-32053571

RESUMO

BACKGROUND: The eosinophilic chronic obstructive pulmonary disease (COPD) is known to be more sensitive to corticosteroid. The sputum microbiome has been shown to affect COPD prognosis, but its role in acute exacerbations of eosinophilic COPD is unclear. This study aimed to investigate the dynamic changes of the airway microbiome in patients with acute exacerbations of eosinophilic COPD. METHODS: Fifty-seven patients with acute exacerbations of COPD from the First Affiliated Hospital of Guangxi Medical University between June 2017 and June 2018 were divided into two groups. Patients with eosinophils ≥300 cells/µL in the peripheral venous blood were assigned to the eosinophilic group (Eos) and the rest to the non-eosinophilic group (Noneos). All patients received similar treatment including inhaled budesonide according to the guidelines. The induced sputum microbiome was analyzed on the 1st and 7th day of treatment using the 16S ribosomal RNA (rRNA) method. The levels of interleukin (IL)-6 and IL-8 were measured in the plasma and the sensitivity to corticosteroids was determined in isolated peripheral blood mononuclear cells. Quantitative data were compared between the two groups using the independent samples t test or Mann-Whitney U test. Categorical data were evaluated using Chi-squared test or Fisher's exact test. RESULTS: Twenty-six patients were classified into Eos group and 31 patients were classified into Noneos group. Prior to treatment, the alpha diversity (Shannon index) (2.65 ±â€Š0.63 vs. 2.56 ±â€Š0.54, t = 0.328, P = 0.747) and the structure of the sputum microbiome were similar in the Eos group and the Noneos group. After 7 days of treatment, alpha diversity increased in both groups, while the microbiome richness (Ace index) was significantly lower in the Eos group (561.87 ±â€Š109.13 vs. 767.88 ±â€Š148.48, t = -3.535, P = 0.002). At the same time, IL-6 (12.09 ±â€Š2.85 pg/mL vs. 15.54 ±â€Š2.45 pg/mL, t = -4.913, P < 0.001) and IL-8 (63.64 ±â€Š21.69 pg/mL vs. 78.97 ±â€Š17.13 pg/mL, t = -2.981, P = 0.004) decreased more significantly in the Eos group, and the percentage of inhibition of IL-8 at dexamethasone concentrations 10 to 10 mol/L were significantly higher in the Eos group than those in the Noneos group (all P < 0.05). CONCLUSIONS: The induced sputum microbiome richness decreased more significantly following treatment in the Eos patients compared to the Noneos patients. The lower plasma inflammatory factor levels and the higher percentage of inhibition of IL-8 might be due to higher corticosteroid sensitivity in Eos patients.

4.
Exp Cell Res ; : 111897, 2020 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-32035951

RESUMO

Mucins are major macromolecular components of lung mucus that are mainly responsible for the viscoelastic property of mucus. MUC5AC is a major mucin glycoprotein that is hypersecreted in asthmatic individuals. Vascular endothelial growth factor (VEGF) has been implicated in inflammatory and airway blood vessel remodeling in asthmatics. Our previous studies indicate that VEGF upregulates MUC5AC expression by interacting with VEGF receptor 2 (VEGFR2). It has been shown that dexamethasone (Dex) downregulates MUC5AC expression; however, the underlying mechanisms have not been completely elucidated. Therefore, we sought to investigate the effect of Dex on MUC5AC expression induced by VEGF and study the underlying mechanisms. We tested the effects of Dex on VEGFR2 and RhoA activation, caveolin-1 expression, and the association of caveolin-1 and VEGFR2 in primary bronchial epithelial cells. Dex downregulated MUC5AC mRNA and protein levels in a dose- and time-dependent manner, and suppressed the activation of VEGFR2 and RhoA induced by VEGF. Additionally, Dex upregulated caveolin-1 protein levels in a dose- and time-dependent manner. Furthermore, phospho-VEGFR2 expression was decreased through overexpression of caveolin-1 and increased after caveolin-1 knockdown. Dex treatment attenuated the VEGF-decreased association of caveolin-1 and VEGFR2. Collectively, our findings suggest that Dex downregulates VEGF-induced MUC5AC expression by inactivating VEGFR2 and RhoA. Furthermore, decreased MUC5AC expression by Dex was related to the increased association of caveolin-1 with VEGFR2. Further studies characterizing these mechanisms are required to facilitate the development of improved treatment strategies for asthma.

5.
Prep Biochem Biotechnol ; : 1-7, 2020 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-32069137

RESUMO

Stemonae Radix, a medicinal and edible herb, has been reported to possess various pharmacological effects. In the present study, Stemonae Radix was fermented by fungi to improve the antioxidant and anti-tyrosinase activities. The results showed that Stemonae Radix fermented by Mucor circinelloides T2-12 exhibited two-folds more antioxidant and anti-tyrosinase activities than non-fermented material. The increased activity might be ascribed to the improvement of total phenolic content, hydrolyzation of glucosides and esters of phenolics and metabolism of saccharides according to ultraviolet and nuclear paramagnetic resonance spectroscopy. This paper suggested that fermenting Stemonae Radix with M. circinelloides T2-12 is effective to increase antioxidant and anti-tyrosinase effects and Stemonae Radix fermented by M. circinelloides T2-12 might be newly alternative of natural antioxidant and tyrosinase inhibitor. The present study is the first to report that pure strain fermentation processing is effective in improving the antioxidant and anti-tyrosinase activities of Stemonae Radix.

6.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 51(1): 67-73, 2020 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-31950792

RESUMO

Objective: To develop and verify a flow cytometric measurement of reticulocytes (RETs) micronucleus in rat bone marrow. Methods: In our flow cytometric protocol, reticulocytes, leukocytes and DNA were labeled by anti-CD71-fluorescein isothiocyanate (FITC), anti-CD45-phycoerythrin (PE) and DRAQ5, respectively. Sprague-Dawley (SD) rats were assigned to four treatment groups randomly, and were exposed to ethyl methanesulfonate (EMS), cyclophosphamide (CP), ethyl nitrosourea (ENU) and colchicine (COL) respectively. Each treatment group was divided into four subgroups (5 rats per subgroup) according to different exposure dosage. A exposure dose of 0 was used as vehicle control for each group. Rats were administered with testing mutagens by gavage twice with a 24 h interval. Bone marrow from both femurs were collected 24 h after the last administration. The frequency of micronucleated reticulocytes (MN-RETs) and the percentage of reticulocytes (RETs%) were determined by flow cytometric measurement established in this study. And the manual counting method with microscope (by Giemsa staining) was conducted at the same time. Results: A method for detection of reticulocyte micronucleus in bone marrow based on flow cytometry was successfully established. The MN-RETs in rat bone marrow of 20 SD rats treated by vehicle (i.e., background value of MN-RETs) was 0.83‰±0.12‰ by this method. The background value of MN-RETs in manual enumeration method was 1.43‰±0.44‰. It was obvious that the flow cytometric method had lower background value and more stable results. The trend, in which MN-RETs ascended and RETs% descended with increasing dose, can be detected by both methods in rats that exposed to EMS, CP, ENU and COL. Both methods were good to detect the correlation of induced-MN-RETs with four testing mutagens (the correlation coefficients were ranged from 0.834 3 to 0.913 7). Conclusion: With its sensitivity, rapidity, easy operation and low background value, the three-color flow cytometric enumerative protocol established in our laboratory can be used as a good substitute for manual micronucleus counting method and used in genotoxicity assessment of chemical substances.


Assuntos
Medula Óssea , Citometria de Fluxo , Reticulócitos , Animais , Testes para Micronúcleos , Ratos , Ratos Sprague-Dawley , Reticulócitos/citologia
7.
Ying Yong Sheng Tai Xue Bao ; 31(1): 333-339, 2020 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-31957412

RESUMO

A large amount of azo dye wastewater is discharged into the environment, with serious risks to ecosystems and human health. Therefore, the development of treatment technology of azo dye wastewater was of practical significance. Photocatalytic methods showed promising application prospects due to easy to implement and effective. In this study, layered black phosphorus nanosheet (LBP) was used as a catalyst through liquid phase exfoliation method. Methyl orange (MO) was employed as a model azo dye to investigate the catalytic mechanism of LBP. The dominant transient species involved in the photocatalytic reaction was probed by quenching and fluorescence probe experiments. Degradation pathways of MO were proposed according to degradation products identified by the liquid chromatography-mass spectrometry. The results showed that degradation rate (kobs) of MO at acidic condition (pH=3.0) or alkaline condition (pH=11.0) was higher than that at neutral condition (pH=7.0). Degradation pathways of MO included that the azo bond was attacked by hydroxyl radicals (·OH) photogenerated by the LBP, and the intermediate products were further oxidized by ·OH to produce N, N-dimethyl-4-(2-p-phenylmethylhydrazine) aniline, 2-(dimethylamino)-5-((4(dimethylamino) phenyl) diazenyl) phenol and N, N-dimethyl-4-nitroaniline.


Assuntos
Ecossistema , Fósforo , Compostos Azo , Águas Residuárias
8.
Apoptosis ; 2020 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-31993850

RESUMO

Arterial media calcification is related to mitochondrial dysfunction. Protective mitophagy delays the progression of vascular calcification. We previously reported that lactate accelerates osteoblastic phenotype transition of VSMC through BNIP3-mediated mitophagy suppression. In this study, we investigated the specific links between lactate, mitochondrial homeostasis, and vascular calcification. Ex vivo, alizarin S red and von Kossa staining in addition to measurement of calcium content, RUNX2, and BMP-2 protein levels revealed that lactate accelerated arterial media calcification. We demonstrated that lactate induced mitochondrial fission and apoptosis in aortas, whereas mitophagy was suppressed. In VSMCs, lactate increased NR4A1 expression, leading to activation of DNA-PKcs and p53. Lactate induced Drp1 migration to the mitochondria and enhanced mitochondrial fission through NR4A1. Western blot analysis of LC3-II and p62 and mRFP-GFP-LC3 adenovirus detection showed that NR4A1 knockdown was involved in enhanced autophagy flux. Furthermore, NR4A1 inhibited BNIP3-related mitophagy, which was confirmed by TOMM20 and BNIP3 protein levels, and LC3-II co-localization with TOMM20. The excessive fission and deficient mitophagy damaged mitochondrial structure and impaired respiratory function, determined by mPTP opening rate, mitochondrial membrane potential, mitochondrial morphology under TEM, ATP production, and OCR, which was reversed by NR4A1 silencing. Mechanistically, lactate enhanced fission but halted mitophagy via activation of the NR4A1/DNA-PKcs/p53 pathway, evoking apoptosis, finally accelerating osteoblastic phenotype transition of VSMC and calcium deposition. This study suggests that the NR4A1/DNA-PKcs/p53 pathway is involved in the mechanism by which lactate accelerates vascular calcification, partly through excessive Drp-mediated mitochondrial fission and BNIP3-related mitophagy deficiency.

9.
Clin Chim Acta ; 502: 183-190, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31901478

RESUMO

Extracellular acidification in atherosclerosis-prone regions of arterial walls is considered pro-atherosclerotic by exerting detrimental effect on macrophages, endothelial cells (ECs) and vascular smooth muscle cells (VSMCs). Acid-sensing ion channels (ASICs), a family of extracellular H+ (proton)-gated cation channels, are present extensively in the nervous system and other tissues, implying physiologic as well as pathophysiologic importance. Aberrant activation of ASICs is thought to be associated in EC dysfunction, macrophage phenotypic switch, and VSMC migration and proliferation. Although in vitro evidence acknowledges the contribution of ASIC activation in atherosclerosis, no direct evidence confirms their pro-atherosclerotic roles in vivo. In this review, the effect of extracellular acidity on three major contributors, ECs, macrophages, and VSMCs, is discussed focusing on the potential roles of ASICs in atherosclerotic development and underlying pathology. A more comprehensive understanding of ASICs in these processes may provide promising new therapeutic targets for treatment and prevention of atherosclerotic diseases.

10.
Dalton Trans ; 49(5): 1674-1680, 2020 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-31951247

RESUMO

Elucidations on the structure-activity correlations of non-Pt coordination polymer (CP)-based photocatalysts are highly significant for both the enhancement in catalytic activity and large-scale industrial applications of sustainable hydrogen from water splitting. Herein, three isostructural [Cu(HL)2(R-BDC)]n (denoted as Cu-CP-R, HL = 4'-(4-hydroxyphenyl)-4,2':6',4''-terpyridine, R-BDC = 2-R-1,4-benzenedicarboxylate, R = NO2, OH and Br) CPs were solvothermally synthesized by varying the substituents attached to benzenedicarboxylate, which together with two previously reported analogues (R = NH2 and H) were used as photocatalysts to systematically explore the substitution effect on the hydrogen evolution activity. These five CPs feature isomorphic layered motifs with axially elongated CuII octahedra extended alternately by ditopic HL and R-BDC2- connectors, in which R behaves structurally as a non-coordinate group. The hydrogen production rate over the Cu-CP-R photocatalysts increased from 0.21 to 2.34 mmol g-1 h-1, which followed the order of -NH2 > -NO2 > -H > -OH > -Br. Furthermore, the combined experimental and theoretical investigations reveal that the free R moiety significantly dominates the photocatalytic activity by shifting the d states of the CuII ion towards the Fermi level, controlling the potential of the conduction band and quickening the charge transfer ability. These important findings can provide informative hints for the design of high-performance, earth-abundant non-noble metal CP-based semi-conductive photocatalysts.

11.
Clin Chim Acta ; 503: 70-75, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31945340

RESUMO

Atherosclerosis, a complex multifactorial disease, is the leading cause of acute cardiovascular events. Substantial evidence confirms that chronic stress plays a pivot role in the occurrence and development of atherosclerosis, but the specific mechanism remains unclear. Autophagy serves as a safeguard mechanism for sustaining cellular homeostasis via eliminating unnecessary or/and harmful components, and damaged organelles in response to various stress. An increasing number of studies indicate that autophagy plays vital roles in the development of atherosclerosis. Therefore, understanding the role of chronic stress in the regulation of autophagy may provide new insight into prevention and treatment atherosclerotic disease, especially with respect to emerging targeted therapy. In present review, we focus on changes in autophagic function under chronic stress and its relationship to atherosclerosis.

12.
J Ethnopharmacol ; 252: 112617, 2020 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-31988014

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Herbal medicine contains hundreds of natural products, and studying their absorption, metabolism, distribution, and elimination presents great challenges. Gelsemium elegans (G. elegans) is a flowering plants in the Loganiaceae family. The plant is known to be toxic and has been used for many years as a traditional Chinese herbal medicine for the treatment of rheumatoid arthritis, neuropathic pain, spasticity, skin ulcers and cancer. It was also used as veterinary drugs for deworming, promoting animal growth, and pesticides. At present, studies on the metabolism of G. elegans have primarily focused on only a few single available reference ingredients, such as koumine, gelsemine and gelsedine. MATERIAL AND METHODS: The goal of this work is to elucidate the overall metabolism of whole G. elegans powder in goats using high-performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry (HPLC/QqTOF-MS). RESULTS: Analyses of plasma, urine and fecal samples identified or tentatively characterized a total of 44 absorbed natural products and 27 related produced metabolites. Gelsedine-type, sarpagine-type and gelsemine-type alkaloids were the compounds with the highest metabolite formation. In the present study, most natural products identified in G. elegans were metabolized through glucuronidation and oxidation. Hydrogenation, dehydrogenation and demethylation also occurred. CONCLUSION: To our knowledge, this is the first report of the metabolite profiling of the G. elegans crude extract in goats, which is of great significance for a safer and more rational application of this herbal medicine.

13.
Chem Commun (Camb) ; 56(14): 2135-2138, 2020 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-31970341

RESUMO

Based on the structural programmability and spatial addressability of DNA nanodevices, a target-triggered, enzyme-free 3D DNA walker, comprising of hairpin DNA assembled gold nanoparticles with a local catalytic hairpin assembly reaction, was developed for the highly sensitive detection of intracellular tumor-associated microRNAs.

14.
Insect Sci ; 27(2): 292-303, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30156035

RESUMO

Juvenile hormone (JH), a growth regulator, inhibits ecdysteroid-induced metamorphosis and controls insect development and diapause. Methoprene-tolerant (Met) and Krüppel homolog 1 (Kr-h1) are two proteins involved in JH action. To gain some insight into their function in development of Sitodiplosis mosellana, an insect pest undergoing obligatory larval diapause at the mature 3rd instar stage, we cloned full-length complementary DNAs of Met and Kr-h1 from this species. SmMet encoded a putative protein, which contained three domains typical of the bHLH-PAS family and eight conserved amino acid residues important for JH binding. SmKr-h1 encoded a protein showing high sequence homology to its counterparts in other species, and contained all eight highly conserved Zn-finger motifs for DNA-binding. Expression patterns of SmMet and SmKr-h1 were developmentally regulated and JH III responsive as well. Their mRNA abundance increased as larvae entered early 3rd instar, pre-diapause and maintenance stages, and peaked during post-diapause quiescence, a pattern correlated with JH titers in this species. Different from reduced expression of SmMet, SmKr-h1 mRNA increased at mid-to-late period of post-diapause development. Topical application of JH III on diapausing larvae also induced the two genes in a dose-dependent manner. Expression of SmMet and SmKr-h1 clearly declined in the pre-pupal phase, and was significantly higher in female adults than male adults. These results suggest that JH-responsive SmMet and SmKr-h1 might play key roles in diapause induction and maintenance as well as in post-diapause quiescence and adult reproduction, whereas metamorphosis from larvae to pupae might be correlated with their reduced expression.


Assuntos
Culicomorfos/genética , Proteínas de Insetos/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , Fatores de Transcrição Hélice-Alça-Hélice Básicos , Culicomorfos/crescimento & desenvolvimento , Culicomorfos/metabolismo , Diapausa de Inseto , Proteínas de Drosophila , Feminino , Proteínas de Insetos/metabolismo , Hormônios Juvenis/metabolismo , Fatores de Transcrição Kruppel-Like , Masculino
15.
Stem Cells ; 38(2): 218-230, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31648394

RESUMO

Huntington's disease (HD) is a neurodegenerative disorder caused by a mutation in the huntingtin (HTT) gene that results in the production of neurotoxic mutant HTT (mHTT) protein. Suppressing HTT production with antisense oligonucleotides (ASOs) is a promising treatment strategy for HD; however, the difficulty of delivering ASOs to deep brain structures is a major barrier for its clinical application. The glymphatic system of astrocytes involving aquaporin 4 (AQP-4) controls the entry of macromolecules from the cerebrospinal fluid into the brain. Mesenchymal stem cells (MSCs) target astrocytes to inhibit neuroinflammation. Here we examined the glymphatic distribution of ASO in the brain and the therapeutic potential of combining intravenously injection of mesenchymal stem cells (IV-MSC) and ASOs for the treatment of HD. Our results show that Cy3-labeled ASOs entered the brain parenchyma via the perivascular space following cisternal injection, but the brain distribution was significantly lower in AQP-4-/- as compared with wild-type mice. Downregulation of the AQP-4 M23 isoform was accompanied by decreased brain levels of ASOs in BACHD mice as well as an increase in astrogliosis and phosphorylation of nuclear factor κB (NF-κB) p65. IV-MSC treatment restored AQP-4 M23 expression, attenuated astrogliosis, and decreased NF-κB p65 phosphorylation; it also increased the brain distribution of ASOs and enhanced the suppression of mHTT in BACHD mice. These results suggest that modulating glymphatic activity using IV-MSC is a novel strategy for improving the potency of ASO in the treatment of HD.

16.
J Environ Manage ; 253: 109698, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31704594

RESUMO

The significant role of high-quality data in environmental policymaking has led to the Chinese central government's concrete efforts to improve its monitoring system, which had long been plagued with data manipulation by local governments. The most remarkable policy innovation of the last decade in this area has been the introduction of a critical external oversight-profit-making third-party organizations-by the central government to monitor local governments' environmental performance. Despite the significance of third-party environmental monitoring, little is known about its effectiveness in improving data accuracy and whether and how it brings about changes to China's environmental governance. Framed within the literature on China's intergovernmental relationship and adopting a regression discontinuity model with a national database of air quality, this study examines whether third-party monitoring improves the accuracy of environmental data in China, and if so, how this approach can remedy the problem of data manipulation. Results show that data accuracy has been improved after the involvement of third-party organizations, providing evidence that supports China's efforts to advance its environmental governance from a mono-centric and non-participatory policy process to one that integrates both authoritarian control and market-based mechanisms. We discuss policy implications of this finding for environmental governance in China.


Assuntos
Poluição do Ar , Política Ambiental , China , Conservação dos Recursos Naturais , Confiabilidade dos Dados , Monitoramento Ambiental
17.
J Cell Mol Med ; 24(3): 2319-2329, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31880857

RESUMO

Cardiac fibrosis is a key factor to determine the prognosis in patient with myocardial infarction (MI). The aim of this study is to investigate whether the transcriptional factor paired-related homeobox 2 (Prrx2) regulates Wnt5a gene expression and the role in myocardial fibrosis following MI. The MI surgery was performed by ligation of left anterior descending coronary artery. Cardiac remodelling was assessed by measuring interstitial fibrosis performed with Masson staining. Cell differentiation was examined by analysis the expression of alpha-smooth muscle actin (α-SMA). Both Prrx2 and Wnt5a gene expressions were up-regulated in mice following MI, accompanied with increased mRNA and protein levels of α-SMA, collagen I and collagen III, compared to mice with sham surgery. Adenovirus-mediated gene knock down of Prrx2 increased survival rate, alleviated cardiac fibrosis, decreased infarction sizes and improved cardiac functions in mice with MI. Importantly, inhibition of Prrx2 suppressed ischaemia-induced Wnt5a gene expression and Wnt5a signalling. In cultured cardiac fibroblasts, TGF-ß increased gene expressions of Prrx2 and Wnt5a, and induced cell differentiations, which were abolished by gene silence of either Prrx2 or Wnt5a. Further, overexpression of Prrx2 or Wnt5a mirrored the effects of TGF-ß on cell differentiations of cardiac fibroblasts. Gene silence of Wnt5a also ablated cell differentiations induced by Prrx2 overexpression in cardiac fibroblasts. Mechanically, Prrx2 was able to bind with Wnt5a gene promoter to up-regulate Wnt5a gene expression. In conclusions, targeting Prrx2-Wnt5a signalling should be considered to improve cardiac remodelling in patients with ischaemic heart diseases.

18.
Int J Mol Sci ; 20(23)2019 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-31795136

RESUMO

An easily prepared benzothiazole-based probe (BHM) was prepared and characterized by general spectra, including 1H NMR, 13C NMR, HRMS, and single-crystal X-ray diffraction. Based on the synergistic mechanism of the inhabitation of intramolecular charge transfer (ICT), the BHM displayed high selectivity and sensitivity for Al3+ in DMF/H2O (v/v, 1/1) through an obvious blue-shift in the fluorescent spectrum and significant color change detected by the naked eye, respectively. The binding ratio of BHM with Al3+ was 1:1, as determined by the Job plot, and the binding details were investigated using FT-IR, 1H NMR titration, and ESI-MS analysis. Furthermore, the BHM was successfully applied in the detection of Al3+ in the Songhua River and on a test stripe. Fluorescence imaging experiments confirmed that the BHM could be used to monitor Al3+ in human stromal cells (HSC).

19.
Molecules ; 24(23)2019 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-31810277

RESUMO

This study aimed to determine the effect of applying stimulatory agents to liquid cultured Inonotus obliquus on the simultaneous accumulation of exo-polysaccharides (EPS) and their monosaccharide composition. Different stimulatory agents (VB6, VB1, betulin and birch extract) were investigated for their effects on active exo-polysaccharides by submerged fermentation of I. obliquus. The mycelial biomass, reducing sugar content, EPS yield and α-glucosidase inhibition rate were determined, and the EPS obtained was analyzed for monosaccharide composition. The results showed that the addition of all the four stimulatory agents could significantly increase the inhibitory activity against α-glucosidase of EPS than the control, whereas EPS from 4 µg/mL VB1-containing medium had the best effect with an estimated IC50 value 24.34 µg/mL. Among the four stimulatory agents, VB6 gave maximum production of mycelial biomass and EPS at the concentration of 4 µg/mL with a increase of 50.79% and 114.46%, respectively. In addition, betulin had a significant effect on increasing the EPS yield and activity, and birch extract had a significantly stimulatory effect on the mycelial growth and the polysaccharides activity, only slightly worse than VB6 and VB1. Moreover, the addition of different stimulatory agents changed the monosaccharide composition of polysaccharides, which had a correlation with polysaccharide activity.

20.
Respir Res ; 20(1): 282, 2019 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-31831011

RESUMO

BACKGROUND: Airway mucus hypersecretion is an important pathophysiological feature in asthma. Mucins are glycoproteins that are mainly responsible for the viscoelastic property of mucus, and MUC5AC is a major mucin glycoprotein that is overproduced in asthma. Vascular endothelial growth factor (VEGF) has been implicated in inflammatory and airway blood vessel remodeling in asthmatics. Therefore, we sought to investigate the effect of VEGF on MUC5AC expression and study the underlying mechanisms. METHODS: In order to elucidate the precise mechanism underlying the effect of VEGF on MUC5AC expression, we tested the effects of VEGF on RhoA activation and the association of caveolin-1 and VEGFR2 in Primary Bronchial Epithelial Cells. RESULTS: VEGF up-regulated MUC5AC mRNA and protein levels in a dose- and time-dependent manner, and activated RhoA. Additionally, VEGF-induced MUC5AC expression and RhoA activation were enhanced by disrupting caveolae with cholesterol depletion and reversed by cholesterol repletion, and inhibited by a selective VEGF receptor 2 (VEGFR2) inhibitor SU1498. Furthermore, phospho-VEGFR2 expression was decreased via overexpression of caveolin-1. VEGF treatment reduced the association of caveolin-1 and VEGFR2. CONCLUSION: Collectively, our findings suggest that VEGF up-regulates MUC5AC expression and RhoA activation by interaction with VEGFR2, and this phenomenon was related with the association of caveolin-1 and VEGFR2. Further studies on these mechanisms are needed to facilitate the development of treatments for asthma.

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