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1.
J Environ Sci (China) ; 87: 149-162, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31791488

RESUMO

A graphite carbon nitride (g-C3N4) modified Bi4O5I2 composite was successfully prepared in-situ via the thermal treatment of a g-C3N4/BiOI precursor at 400°C for 3 hr. The as-prepared g-C3N4/Bi4O5I2 showed high photocatalytic performance in Methyl Orange (MO) degradation under visible light. The best sample presented a degradation rate of 0.164 min-1, which is 3.2 and 82 times as high as that of Bi4O5I2 and g-C3N4, respectively. The g-C3N4/Bi4O5I2 was characterized by X-ray powder diffractometer (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), Raman, X-ray photoelectron spectroscopy (XPS), ultraviolet-visible diffuse reflectance spectra (DRS), electrochemical impedance spectroscopy (EIS) and transient photocurrent response in order to explain the enhanced photoactivity. Results indicated that the decoration with a small amount of g-C3N4 influenced the specific surface area only slightly. Nevertheless, the capability for absorbing visible light was improved measurably, which was beneficial to the MO degradation. On top of that, a strong interaction between g-C3N4 and Bi4O5I2 was detected. This interplay promoted the formation of a favorable heterojunction structure and thereby enhanced the charge separation. Thus, the g-C3N4/Bi4O5I2 composite presented greater charge separation efficiency and much better photocatalytic performance than Bi4O5I2. Additionally, g-C3N4/Bi4O5I2 also presented high stability. •O2- and holes were verified to be the main reactive species.


Assuntos
Compostos Azo/química , Processos Fotoquímicos , Grafite/química , Luz , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão , Compostos de Nitrogênio/química , Espectroscopia Fotoeletrônica
2.
Food Chem ; 310: 125914, 2019 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-31835223

RESUMO

Qualitative and quantitative metabolomics analysis of all small-molecule metabolites in organisms is an emerging omics technology alongside genomics and proteomics. Plant metabolites are extremely diverse both within species and in terms of their physiological function. Plant metabolomics studies use mainly liquid/gas chromatography-mass spectrometry (LC/GC-MS) and nuclear magnetic resonance (NMR) techniques combined with chemometrics and multivariate statistical analysis to analyze plant metabolites, and metabolomics plays a key role in agricultural and food science research. In this review, we discuss the status of metabolomics in soybean in response to abiotic stresses such as drought, heat, salinity, flooding, chilling and heavy metal stresses and analyze the challenges and opportunities. Furthermore, the notable metabolites detected in response to different stresses are summarized to provide a reference for applications of metabolomics in soybean research.

3.
Sci Total Environ ; : 134687, 2019 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-31812415

RESUMO

In high-intensity human activity areas, such as metropolises, rapid changes in land use, agricultural intensification, and population urbanization have resulted in profound and complex transformations in socio-economic ecosystems. The study of ecosystem service (ES) bundle is conducive to various aspects, such as determination of the variation characteristics of ES; identification of the mechanism of interdependence within ES; and driving mechanism of socio-economic-ecological factors to ES to maintain the sustainable development of the region. The research areas include Beijing and its surrounding areas. Ten ES, including grain providing (GP), water yield (WY), carbon sequestration (CS), soil retention (SEC), purified water service, cultural services, and habitat quality (HQ) were selected for valuing and mapping. The ES paired trade-offs and synergetic relationship, bundle was determined, and the bundles' service types and spatial distribution characteristics were analyzed. Subsequently, GeoDetector was used for detecting the factors affecting the bundles' distribution. Results showed that WY, CS, SEC, and HQ were bounded by Tai-hang and Yanshan Mountains. Among the 45 pairs of ES, 38 pairs bore significant correlation. Multiple services had different degrees of positive and negative correlations with other services. For example, GP had a high positive correlation with WY while bearing a high negative correlation with HQ. Seven bundles include SEC, culture, urban, HQ, agriculture, water supply and purification, and water purification. Various factors played decisive roles in the bundles' spatial distribution. Among them, the investment capacity and demand for ecological protection depend on the level of GDP and POP. The formulation of agricultural planting plans is inseparable from TADEM. ASL is directly related to species richness. Results indicate that bundle research can identify the areas of the formation of co-occurrence of trade-offs and synergies and support the formulation of ES optimal management plans for different regions through further research of the driving mechanism.

4.
Dalton Trans ; 48(45): 16974-16985, 2019 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-31687705

RESUMO

Herein, we have studied the crystallization of zeolite omega by the solid-state transformation of TMA-magadiite at 100 °C for 12 h. The samples prepared at different times were subjected to XRD, SEM, IR, Raman and solid MAS NMR analyses to investigate the crystallization behaviors and changes in the medium-range structure during the synthesis process and a comprehensive mechanism was proposed. It has been demonstrated that the 5Rs and 6Rs in magadiite are partially retained in the system and participate in the growth of zeolite omega. The 4Rs were formed after heating for 4 h. The synthesis time of the zeolite omega using this method is shorter than that using the magadiite hydrothermal conversion method (about 72 h), because special composition building units, which have similarities to the structure of zeolite omega, were formed and adsorbed on the surface of the TMA-magadiite, and then provided a growth surface for the synthesis of targets. In addition, recycling the waste mother liquid produced in the preparation of the precursor was done to achieve the low cost and green synthesis. Finally, several factors influencing the reaction are discussed.

5.
J Mater Chem B ; 7(42): 6623-6629, 2019 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-31591622

RESUMO

Benefiting from high spatial resolution and large penetration depth, NIR-II (second near-infrared spectral region, 900-1700 nm) fluorescence imaging based on US Food and Drug Administration (FDA)-approved indocyanine green (ICG) is expected to be a good approach for clinical applications. As of now, nearly all reported works on ICG-assisted NIR-II fluorescence imaging are macro-imaging while micro-angiography is also a significant imaging modality, especially during the diagnosis and treatment of cerebrovascular diseases. Herein, based on NIR-II fluorescence wide-field microscopy, the high-resolution observation of cerebral vasculature was performed at deep brain tissues in mice via intramuscular (IM) injection of ICG. Altered cerebral vessels in mice after brain embolism were further noticed by means of noninvasive through-skull NIR-II fluorescence microscopy. Moreover, ICG-assisted NIR-II fluorescence confocal microscopy was executed to observe cerebral vasculature, presenting optical sectioning capability and higher spatial resolution.

7.
Cell Chem Biol ; 2019 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-31653597

RESUMO

Proprotein convertase substilisin-like/kexin type 9 (PCSK9) is a serine protease involved in a protein-protein interaction with the low-density lipoprotein (LDL) receptor that has both human genetic and clinical validation. Blocking this protein-protein interaction prevents LDL receptor degradation and thereby decreases LDL cholesterol levels. Our pursuit of small-molecule direct binders for this difficult to drug PPI target utilized affinity selection/mass spectrometry, which identified one confirmed hit compound. An X-ray crystal structure revealed that this compound was binding in an unprecedented allosteric pocket located between the catalytic and C-terminal domain. Optimization of this initial hit, using two distinct strategies, led to compounds with high binding affinity to PCSK9. Direct target engagement was demonstrated in the cell lysate with a cellular thermal shift assay. Finally, ligand-induced protein degradation was shown with a proteasome recruiting tag attached to the high-affinity allosteric ligand for PCSK9.

8.
Artigo em Inglês | MEDLINE | ID: mdl-31501964

RESUMO

The fluctuating position of an optically trapped cilium tip under untreated and Taxol-treated conditions was used to characterize mechanical properties of the cilium axoneme and its basal body by combining experimental, analytical, and computational tools. We provide, for the first time, evidence that the persistence length of a ciliary axoneme is length-dependent; longer cilia are stiffer than shorter cilia. We demonstrate that this apparent length dependence can be understood by a combination of modeling axonemal microtubules as anisotropic elastic shells and including actomyosin-driven stochastic basal body motion. Our results also demonstrate the possibility of using observable ciliary dynamics to probe interior cytoskeletal dynamics. It is hoped that our improved characterization of cilia will result in deeper understanding of the biological function of cellular flow sensing by this organelle.

9.
Biosens Bioelectron ; 144: 111669, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31494507

RESUMO

8-Hydroxy-2'-deoxyguanosine (8-OH-dG) is a principal stable marker of DNA oxidative damage. Sensitive and specific detection of 8-OH-dG is of great importance for early disease diagnosis. In this paper, we developed an electrochemiluminescence aptasensor for 8-OH-dG detection based on target induced multi-DNA release and nicking enzyme signaling amplification strategy. First, three kinds of short DNAs were aligned on the aptamers immobilized on the magnetic beads. In the presence of 8-OH-dG, the aptamer recognized and specifically bound with 8-OH-dG, leading to the release of three kinds of short DNAs and three-fold signal amplification. Then the released short DNAs hybridized with ferrocence (Fc) labeled hairpin DNA (Fc-HP) immobilized on the gold electrode to form a double strand DNA. Subsequently, nicking endonuclease (Nt.AlwI) recognized the asymmetric sequence in the dsDNA and cleaved the substrate strand (Fc-HP) into two parts, one fragments containing Fc would leave the surface of electrode. Based on the quenching effect of Fc on the electrochemiluminescence (ECL) of Ru(bpy)32+/TPA, a signal-on ECL aptasensor was developed. At the same time, three kinds of short DNAs were released again and reused to initiate the repeated cycles of hybridization-cleavage. Under double signal amplification, this aptasensor achieved a low detection of 25 fM and a wide linear range from 100 fM to 10 nM for 8-OH-dG. Besides, the amount of 8-OH-dG in urine samples derived from different people were determined with satisfactory results.

10.
Theranostics ; 9(19): 5706-5719, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31534513

RESUMO

Rationale: Cerebrovascular diseases, together with malignancies, still pose a huge threat to human health nowadays. With the advantages of its high spatial resolution and large penetration depth, fluorescence bioimaging in the second near-infrared spectral region (NIR-II, 900-1700 nm) and its related imaging-guided therapy based on biocompatible fluorescence dyes have become a promising theranostics method. Methods: The biocompatibility of IR-820 we used in NIR-II fluorescence bioimaging was verified by long-term observation. The model of the mouse with a cranial window, the mouse model of middle cerebral artery occlusion (MCAO) and a subcutaneous xenograft mouse model of bladder tumor were established. NIR-II fluorescence cerebrovascular functional imaging was carried out by IR-820 assisted NIR-II fluorescence microscopy. Bladder tumor was treated by NIR-II fluorescence imaging-guided photothermal therapy. Results: We have found that IR-820 has considerable NIR-II fluorescence intensity, and shows increased brightness in serum than in water. Herein, we achieved real time and in vivo cerebrovascular functional imaging of mice with high spatial resolution and large penetration depth, based on IR-820 assisted NIR-II fluorescence microscopy. In addition, IR-820 was successfully employed for NIR-II fluorescence imaging and photothermal therapy of tumor in vivo, and the subcutaneous tumors were inhibited obviously or eradicated completely. Conclusion: Due to the considerable fluorescence intensity in NIR-II spectral region and the good photothermal effect, biocompatible and excretable IR-820 holds great potentials for functional angiography and cancer theranostics in clinical practice.

11.
J Biol Chem ; 294(40): 14823-14835, 2019 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-31444270

RESUMO

Liquid-liquid phase separation (LLPS) facilitates the formation of condensed biological assemblies with well-delineated physical boundaries, but without lipid membrane barriers. LLPS is increasingly recognized as a common mechanism for cells to organize and maintain different cellular compartments in addition to classical membrane-delimited organelles. Membraneless condensates have many distinct features that are not present in membrane-delimited organelles and that are likely indispensable for the viability and function of living cells. Malformation of membraneless condensates is increasingly linked to human diseases. In this review, we summarize commonly used methods to investigate various forms of LLPS occurring both in 3D aqueous solution and on 2D membrane bilayers, such as LLPS condensates arising from intrinsically disordered proteins or structured modular protein domains. We then discuss, in the context of comparisons with membrane-delimited organelles, the potential functional implications of membraneless condensate formation in cells. We close by highlighting some challenges in the field devoted to studying LLPS-mediated membraneless condensate formation.

12.
Artigo em Inglês | MEDLINE | ID: mdl-31332676

RESUMO

Yeast surface display has emerged as a viable approach for self-immobilization enzyme as whole-cell catalysts. Herein, we displayed Candida rugosa lipase 1 (CRL LIP1) on the cell wall of Pichia pastoris for docosahexaenoic acid (DHA) enrichment in algae oil. After a 96-h culture, the displayed CRL LIP1 achieved the highest activity (380 ± 2.8 U/g) for hydrolyzing olive oil under optimal pH (7.5) and temperature (45 °C) conditions. Additionally, we improved the thermal stability of displayed LIP1, enabling retention of 50% of its initial bioactivity following 6 h of incubation at 45 °C. Furthermore, the content of DHA enhanced from 40.61% in original algae oil to 50.44% in glyceride, resulting in a 1.24-fold increase in yield. The displayed CRL LIP1 exhibited an improved thermal stability and a high degree of bioactivity toward its native macromolecule substrates algae oil and olive oil, thereby expanding its potential for industrial applications in fields of food and pharmaceutical. These results suggested that surface display provides an effective strategy for simultaneous convenient expression and target protein immobilization.

13.
J Immunol Res ; 2019: 2121849, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31317046

RESUMO

Background: Mesangial cells play a prominent role in the development of inflammatory diseases and autoimmune disorders of the kidney. Mesangial cells perform the essential functions of helping to ensure that the glomerular structure is stable and regulating capillary flow, and activated mesangial cells acquire proinflammatory activities. We investigated whether activated mesangial cells display immune properties and control the development of T cell immunity. Methods: Flow cytometry analysis was used to study the expression of antigen-presenting cell surface markers and costimulatory molecules in mesangial cells. CD4+ T cell activation induced by mesangial cells was detected in terms of T cell proliferation and cytokine production. Results: IFN-γ-treated mesangial cells express membrane proteins involved in antigen presentation and T cell activation, including MHC-II, ICAM-1, CD40, and CD80. This finding suggests that activated mesangial cells can take up and present antigenic peptides to initiate CD4+ T cell responses and thus act as nonprofessional antigen-presenting cells. Polarization of naïve CD4+ T cells (Th0 cells) towards the Th1 phenotype was induced by coculture with activated mesangial cells, and the resulting Th1 cells showed increased mRNA and protein expression of inflammation-associated genes. Conclusion: Mesangial cells can present antigen and modulate CD4+ T lymphocyte proliferation and differentiation. Interactions between mesangial cells and T cells are essential for sustaining the inflammatory response in a variety of glomerulonephritides. Therefore, mesangial cells might participate in immune function in the kidney.

14.
Front Pharmacol ; 10: 550, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31178729

RESUMO

Objective: To assess the effectiveness and safety of the total glucosides of paeony (TGP) on the treatment of primary Sjögren's syndrome (pSS) by conducting a meta-analysis. Methods: Eight databases were searched from their inception to December 10, 2018 for randomized controlled trials (RCTs). The Revman 5.3 software was used for this meta-analysis. Results: Nine RCTs which included 770 participants were identified. Pooled results showed that significant difference in Schirmer's test (P < 0.00001) comparing TGP with placebo (PBO). However, the pooled results displayed significant differences in salivary flow rate, Schirmer's test, erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), rheumatoid factor (RF), serum γ-globulin, immunoglobulin G (IgG), IgA, IgM, and effective rate (P ≤ 0.01) in the co-administration of TGP with immunosuppressant (IS) compared with IS alone. Subgroup analyses revealed both heterogeneities in ESR and serum γ-globulin were eliminated, showing combined intervention of TGP + IS being more advantageous than single usage of IS (P < 0.00001). However, the advantage varied among three subgroups and showed a gradual weakening over time. Furthermore, our results showed statistical significance in Schirmer's test (P = 0.0006), when hydroxychloroquine (HCQ) was jointly applied, but not in the case of combined TGP with methotrexate (MTX) (P = 0.41). For the safety analysis, the most common adverse events (AEs) were diarrhea or gastrointestinal discomfort, and no severe AEs were reported in TGP group. Meanwhile, six trials showed statistically insignificant differences between TGP + IS and IS in AEs (P = 0.76). Conclusions: Improving the lacrimal gland secretion (Schirmer's test) is the prominent function of TGP compared with PBO. TGP + IS can improve the clinical symptoms, such as lacrimal and salivary gland secretion function (Schirmer's test, salivary flow rate), inflammatory indices (ESR, CRP, and RF) and immunoglobulins (γ-globulin, IgG, IgA, and IgM) on the basis of IS monotherapy. In addition, TGP has an acceptable safety profile and AEs were not increased when TGP combined with IS in pSS. Therefore, TGP can be considered to be a potentially valid and safe drug for the treatment of pSS in the clinic. In view of the limitations of the included trials, the potential beneficial effectiveness and safety of TGP need additional high-quality, multi-center, and large-scale RCTs to assess its use in pSS treatment.

15.
Adv Mater ; 31(30): e1902504, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31169334

RESUMO

Diagnostics of cerebrovascular structures and microscopic tumors with intact blood-brain barrier (BBB) significantly contributes to timely treatment of patients bearing neurological diseases. Dual NIR-II fluorescence and photoacoustic imaging (PAI) is expected to offer powerful strength, including good spatiotemporal resolution, deep penetration, and large signal-to-background ratio (SBR) for precise brain diagnostics. Herein, biocompatible and photostable conjugated polymer nanoparticles (CP NPs) are reported for dual-modality brain imaging in the NIR-II window. Uniform CP NPs with a size of 50 nm are fabricated from microfluidics devices, which show an emission peak at 1156 nm with a large absorptivity of 35.2 L g-1 cm-1 at 1000 nm. The NIR-II fluorescence imaging resolves hemodynamics and cerebral vasculatures with a spatial resolution of 23 µm at a depth of 600 µm. The NIR-II PAI enables successful noninvasive mapping of deep microscopic brain tumors (<2 mm at a depth of 2.4 mm beneath dense skull and scalp) with an SBR of 7.2 after focused ultrasound-induced BBB opening. This study demonstrates that CP NPs are promising contrast agents for brain diagnostics.


Assuntos
Vasos Sanguíneos/diagnóstico por imagem , Neoplasias Encefálicas/diagnóstico por imagem , Encéfalo/diagnóstico por imagem , Corantes Fluorescentes/química , Animais , Materiais Biocompatíveis/química , Barreira Hematoencefálica/metabolismo , Encéfalo/irrigação sanguínea , Neoplasias Encefálicas/irrigação sanguínea , Linhagem Celular Tumoral , Corantes Fluorescentes/administração & dosagem , Humanos , Raios Infravermelhos , Camundongos , Camundongos Nus , Nanopartículas/química , Imagem Óptica/métodos , Permeabilidade , Técnicas Fotoacústicas/métodos , Polímeros/química
16.
Nanoscale Res Lett ; 14(1): 184, 2019 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-31147797

RESUMO

The refractive index of AlN has a direct influence on AlGaN-based deep ultraviolet optoelectronic devices, such as the external quantum efficiency of light-emitting devices. Revealing the dependence of the refractive index of AlN on the threading dislocations is meaningful since high-density threading dislocations usually exist in AlN. In this paper, the effect of different dislocation densities on the refractive index of AlN is investigated. With the increase of dislocation densities from 4.24 × 108 to 3.48 × 109 cm- 2, the refractive index of AlN decreases from 2.2508 to 2.2102 at 280 nm. Further study demonstrates that the nanoscale strain field around dislocations changes the propagation of light and thus decreases the refractive index of AlN. This study will be beneficial to the design of optoelectronic devices and thus realizing high-performance deep ultraviolet optoelectronic devices.

17.
Tissue Cell ; 58: 61-69, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31133247

RESUMO

This study aimed to investigate the effect of different methylated regions of cyclic-AMP response element binding protein 1 (CREB1) by comparing the high prolificacy (HP) group and low prolificacy (LP) group, which was detected in our previous study. The expression level of CREB1 mRNA in the ovaries of the HP group was higher than in the LP group (P < 0.05). The differential methylated region (DMR) had 4 methylated CG dinucleotides(CGs): -1546, -1544, -1494 and -1464. The DNA methylation levels of -1546 CGs and -1464 CGs were significantly higher in the HP group than in the LP group (P < 0.05). The activity from -1296 to +26 (without DMR) was significantly higher than the activity from -1598 to +26 (with DMR) (P < 0.05). The result of 5-aza-2'-deoxycytidine treatment indicated that the inhibition DNA methylation of DMR reduced the transcription of CREB1. The bioinformatics predictive analysis were found that the -1546 CG site was located in the CCAAT/enhancer-binding protein alpha (CEBPA) binding site and the -1464 CG site was located in the Sp1 binding site. Finally, this study revealed the relationship between the methylation of non-CpG sites of the promoter and transcription of CREB1. This study will provide a theoretical basis of the Hu sheep ovaries associated with DNA methylation.


Assuntos
Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , Metilação de DNA/fisiologia , Regulação da Expressão Gênica/fisiologia , Ovário/metabolismo , Elementos de Resposta/fisiologia , Animais , Ilhas de CpG , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/genética , Feminino , Ovinos
18.
Talanta ; 200: 503-510, 2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31036215

RESUMO

In this work, an ultrasensitive aptasensor for the detection of Mucin 1 (MUC1) was presented based on the target-induced catalytic hairpin assembly combined with excellent mimic peroxidase performance of PtPd bimetallic nanoparticles (PtPdNPs). Traditionally, the cyclic reuse of target protein was achieved by protein conversion with enzyme cleavage or polymerization, which is costly and complex. However, in this work, it can be performed by simple strand displacement. In addition, PtPdNPs, a mimic peroxidase, was used a probe to catalyze the oxidation of tetramethylbenzidine (TMB) by H2O2, leading to the electrochemical signal amplification. With this ingenious design, the prepared aptasensor for MUC1 detection showed a favorable linear response from 100 fg mL-1 to 1 ng mL-1 and a relatively low detection limit of 16 fg mL-1. The proposed biosensor possessed acceptable stability, selectivity and reproducibility for MUC1 assay. Additionally, the fabricated aptasensor has been successfully applied to detect MUC1 in serum samples with satisfactory results. This new strategy supplied one efficient approach to improve signal amplification, which also open an avenue for sensitivity enhancement in targets detection.


Assuntos
Aptâmeros de Nucleotídeos/química , Técnicas Eletroquímicas , Nanopartículas Metálicas/química , Mucina-1/análise , Benzidinas/química , Técnicas Biossensoriais , Catálise , Humanos , Peróxido de Hidrogênio/química , Oxirredução , Paládio/química , Peroxidase/química , Peroxidase/metabolismo , Platina/química
19.
Nat Commun ; 10(1): 1046, 2019 03 05.
Artigo em Inglês | MEDLINE | ID: mdl-30837467

RESUMO

One of the least understood aspects in atmospheric chemistry is how urban emissions influence the formation of natural organic aerosols, which affect Earth's energy budget. The Amazon rainforest, during its wet season, is one of the few remaining places on Earth where atmospheric chemistry transitions between preindustrial and urban-influenced conditions. Here, we integrate insights from several laboratory measurements and simulate the formation of secondary organic aerosols (SOA) in the Amazon using a high-resolution chemical transport model. Simulations show that emissions of nitrogen-oxides from Manaus, a city of ~2 million people, greatly enhance production of biogenic SOA by 60-200% on average with peak enhancements of 400%, through the increased oxidation of gas-phase organic carbon emitted by the forests. Simulated enhancements agree with aircraft measurements, and are much larger than those reported over other locations. The implication is that increasing anthropogenic emissions in the future might substantially enhance biogenic SOA in pristine locations like the Amazon.

20.
J Mol Med (Berl) ; 97(4): 553-561, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30810761

RESUMO

Mesangial proliferative glomerulonephritis (MsPGN) is a glomerular disease characterized by the proliferation of mesangial cells and the accumulation of mesangial matrix. No effective treatment is currently able to stop or reverse the disease process. Here, we isolated metanephric mesenchyme-derived Foxd1+ mesangial precursor cells from E13.5 Foxd1Cre; DTRflox double transgenic embryo mice. The Foxd1+ cells showed the cell-specific expression of high levels of Foxd1 without Six2 and manifested specific cell surface markers of mesenchymal stem cells while retaining their differentiation potential. Next, an anti-Thy1 MsPGN rat model was established, and the Foxd1+ cells were injected into the tail veins 24 h later. We found that the Foxd1+ cells could improve the pathological changes to the kidney and significantly reduce proteinuria by inhibiting the sonic hedgehog pathway. Moreover, the Foxd1+ cells could inhibit PDGF-BB-induced activation of mesangial cells by secreting multiple cytokines, including hepatocyte growth factor. Our study uncovered the novel function of Foxd1+ mesangial precursor cells in repairing the damaged mesangium, stabilizing the structure and function of mesangial cells, and restoring their therapeutic effect on the MsPGN. KEY MESSAGES: It is viable to isolate highly purified metanephric mesenchyme-derived Foxd1+ mesangial precursor cells using transgenic mice. Foxd1+ cells could alleviate experimental mesangial proliferative glomerulonephritis and PDGF-induced mesangial cell proliferation through a variety of mechanisms including inhibiting the sonic hedgehog pathway and secreting multiple cytokines. As the progenitor cells of mesangial cells, Foxd1+ cells could stabilize the structure and function of mesangial cells that had undergone pathological changes.

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