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1.
J Chem Phys ; 160(15)2024 Apr 21.
Article in English | MEDLINE | ID: mdl-38629601

ABSTRACT

Many solid crystals exhibit a structural phase transition where a subset of its ions or entire molecules become orientationally ordered. As to why such ordering occurs remains mostly unresolved. We consider the extremely weak magnetic elements arising from the reorientations of the molecules experiencing mutual resonance to play the chief role. Two new features are identified in d-camphor: (1) the magnetic susceptibility abruptly changes when crossing the order-disorder phase transition at TII-III = 239.8 K during cooling and at TIII-II = 245.2 K during warming and (2) the complex dielectric constant exhibits two successive discontinuities only 0.2 K apart near the critical temperatures when the sweeping rate is only 0.1 K/min. We discuss how the change in entropy associated with order-disorder transitions in plastic crystals represents temporal changes rather than spatial changes in the system. Our findings may be extended to study why many other crystalline solids exhibit orientational ordering and irreversibility.

2.
ACS Nano ; 18(11): 7769-7795, 2024 Mar 19.
Article in English | MEDLINE | ID: mdl-38420949

ABSTRACT

Tumor-associated macrophages (TAMs) play pivotal roles in tumor development. As primary contents of tumor environment (TME), TAMs secrete inflammation-related substances to regulate tumoral occurrence and development. There are two kinds of TAMs: the tumoricidal M1-like TAMs and protumoral M2-like TAMs. Reprogramming TAMs from immunosuppressive M2 to immunocompetent M1 phenotype is considered a feasible way to improve immunotherapeutic efficiency. Notably, nanomaterials show great potential for biomedical fields due to their controllable structures and properties. There are many types of nanomaterials that exhibit great regulatory activities for TAMs' reprogramming. In this review, the recent progress of nanomaterials-involved TAMs' reprogramming is comprehensively discussed. The various nanomaterials for TAMs' reprogramming and the reprogramming strategies are summarized and introduced. Additionally, the challenges and perspectives of TAMs' reprogramming for efficient therapy are discussed, aiming to provide inspiration for TAMs' regulator design and promote the development of TAMs-mediated immunotherapy.


Subject(s)
Nanostructures , Neoplasms , Humans , Tumor-Associated Macrophages , Immunotherapy , Immunosuppressive Agents , Inflammation , Nanostructures/therapeutic use , Tumor Microenvironment , Neoplasms/therapy
3.
Int J Mol Sci ; 24(23)2023 Nov 26.
Article in English | MEDLINE | ID: mdl-38069101

ABSTRACT

Plasmodiophora brassicae (P. brassicae) is a soil-born pathogen worldwide and can infect most cruciferous plants, which causes great yield decline and economic losses. It is not well known how microbial diversity and community composition change during P. brassicae infecting plant roots. Here, we employed a resistant and a susceptible pakchoi cultivar with and without inoculation with P. brassicae to analyze bacterial and fungal diversity using 16S rRNA V3-V4 and ITS_V1 regions, respectively. 16S rRNA V3-V4 and ITS_V1 regions were amplified and sequenced separately. Results revealed that both fungal and bacterial diversity increased, and composition was changed in the rhizosphere soil of the susceptible pakchoi compared with the resistant cultivar. In the four groups of R_mock, S_mock, R_10d, and S_10d, the most relatively abundant bacterium and fungus was Proteobacteria, accounting for 61.92%, 58.17%, 48.64%, and 50.00%, respectively, and Ascomycota, accounting for 75.11%, 63.69%, 72.10%, and 90.31%, respectively. A total of 9488 and 11,914 bacteria were observed uniquely in the rhizosphere soil of resistant and susceptible pakchoi, respectively, while only 80 and 103 fungi were observed uniquely in the correlated soil. LefSe analysis showed that 107 and 49 differentially abundant taxa were observed in bacteria and fungi. Overall, we concluded that different pakchoi cultivars affect microbial diversity and community composition, and microorganisms prefer to gather around the rhizosphere of susceptible pakchoi. These findings provide a new insight into plant-microorganism interactions.


Subject(s)
Microbiota , Mycobiome , Plasmodiophorida , Microbiota/genetics , Plasmodiophorida/genetics , RNA, Ribosomal, 16S/genetics , Rhizosphere , Fungi/genetics , Soil Microbiology , Bacteria/genetics , Soil , Plant Roots/microbiology
4.
Acta Pharmacol Sin ; 43(8): 2156-2167, 2022 Aug.
Article in English | MEDLINE | ID: mdl-34912007

ABSTRACT

Excessive exposure to UVB induces skin diseases. Silibinin, a flavonolignan used for treating liver diseases, is found to be effective against UVB-caused skin epidermal and dermal cell damage. In this study we investigated the molecular mechanisms underlying. Human nonmalignant immortalized keratinocyte HaCaT cells and neonatal human foreskin fibroblasts HFFs were exposed to UVB irradiation. We showed that pre-treatment with silibinin dose-dependently decreased UVB-induced apoptosis of HaCaT cells. Furthermore, we showed that silibinin treatment inhibited nuclear translocation of YAP after UVB irradiation. Molecular docking analysis and DARTS assay confirmed the direct interaction of silibinin with YAP. Silencing YAP by siRNA had no influence on the survival of HaCaT cells, whereas inhibiting classical YAP-TEAD signaling pathway by siRNA targeting TEAD1 or its pharmaceutical inhibitor verteporfin further augmented UVB-induced apoptosis, suggesting that YAP-TEAD pathway was prosurvival, which did not participate in the protective effect of silibinin. We then explored the pro-apoptotic YAP-p73 pathway. p73 was upregulated in UVB-irradiated cells, but reduced by silibinin cotreatment. The mRNA and protein levels of p73 target genes (PML, p21 and Bax) were all increased by UVB but decreased by silibinin co-treatment. Inhibiting p73 by using siRNA reduced UVB-induced apoptosis, suggesting that downregulation of p73 was responsible for the cytoprotective effect of silibinin. In HFFs, the upregulated YAP-p73 pathway by UVB irradiation was also suppressed by silibinin. Collectively, YAP-p73 pathway is a major cause of the death of UVB-exposed epidermal HaCaT cells and dermal HFFs. Silibinin directly inhibits YAP-p73 pathway, exerting the protective action on UVB-irradiated skin cells.


Subject(s)
Silymarin , Apoptosis , Humans , Infant, Newborn , Molecular Docking Simulation , RNA, Small Interfering/genetics , RNA, Small Interfering/pharmacology , Silybin/pharmacology , Silymarin/pharmacology
5.
Biomed Pharmacother ; 136: 111265, 2021 Apr.
Article in English | MEDLINE | ID: mdl-33450490

ABSTRACT

Inhibition of tumor angiogenesis is a highly effective strategy for cancer treatment. Human antigen R (HuR), an RNA-binding protein, is overexpressed in many cancers and regulates the mRNAs of multiple angiogenic factors by binding to the adenylate-uridylate-rich element in their 3' untranslated region. HuR protein has been demonstrated to be an important regulatory factor in macrophage-mediated angiogenesis, a process in which macrophages are critical for tumor progression. Muscone is a synthetic equivalent of musk, and recent studies have shown that it has a regulatory effect on angiogenesis. In this study, we synthesized five series of muscone derivatives and discovered that compound ZM-32 was effective in preventing HuR RRM1/2-Vegf-a mRNA complex formation. ZM-32 bound to HuR RRM1/2 protein with a KD value of 521.7 nmol/L. Furthermore, ZM-32 inhibited endothelial cell proliferation, migration, and tubule formation, and suppressed the VEGF/VEGFR2/ERK1/2 signaling axis mediated by macrophages in vitro. We also demonstrated that ZM-32 effectively prevented the proliferation and migration of breast cancer cells and inhibited the growth and angiogenesis of MDA-MB-231 xenograft tumors without any obvious toxicity in vivo. Mechanistically, exposure to ZM-32 influenced the mRNA stability of Vegf-a and Mmp9 in a HuR-dependent manner in both macrophages and MDA-MB-231 cells. Thus, in this study we identified a new muscone derivative, ZM-32, with anti-angiogenesis effects mediated via targeting HuR in breast cancer, that may become a potentially valuable lead compound for anti-cancer angiogenesis.


Subject(s)
Angiogenesis Inhibitors/pharmacology , Breast Neoplasms/drug therapy , Cycloparaffins/pharmacology , ELAV-Like Protein 1/metabolism , Matrix Metalloproteinase 9/metabolism , Neovascularization, Pathologic , Vascular Endothelial Growth Factor A/metabolism , Animals , Breast Neoplasms/enzymology , Breast Neoplasms/genetics , Breast Neoplasms/pathology , Cell Line, Tumor , Cell Movement/drug effects , Cell Proliferation/drug effects , ELAV-Like Protein 1/genetics , Female , Gene Expression Regulation, Neoplastic , Humans , Macrophages/drug effects , Macrophages/metabolism , Matrix Metalloproteinase 9/genetics , Mice , Mice, Nude , RAW 264.7 Cells , RNA Stability , RNA, Messenger/genetics , RNA, Messenger/metabolism , Signal Transduction , Vascular Endothelial Growth Factor A/genetics , Xenograft Model Antitumor Assays
6.
Environ Pollut ; 255(Pt 2): 113292, 2019 Dec.
Article in English | MEDLINE | ID: mdl-31597112

ABSTRACT

The wide application of bisphenol A (BPA) leads to the emergence of BPA residuals in natural water environments. Dissolved organic matter (DOM) existed in water can bind with BPA, hence influencing the migration and transformation of BPA in aquatic environments. pH is a crucial factor governing the binding interactions between DOM and BPA. However, the mechanisms driven the binding process under different pH conditions are still unclear. In this study, the interactions between BPA and humic acids (HA), a primary component of DOM, are investigated over a wide pH range of 3-12 by integrating fluorescence quenching, dynamic light scattering and microcalorimetry. pH dependence of the binding interactions between HA and BPA are interpreted from a thermodynamic perspective. The results indicate that HA can spontaneously interact with BPA to form a stable HA-BPA complex. With the increasing pH, the binding interactions change from entropy driven to entropy-enthalpy co-driven. Hydrophobic force dominate the binding interactions under acidic condition. The synergy of hydrophobic force and hydrogen bond promotes the binding process under neutral condition. Under alkaline conditions, electrostatic repulsion participates the binding process in addition to hydrophobic force and hydrogen bond, weakening the binding strength. Therefore, neutral pH is favorable for HA to bind with BPA, consequently enhancing the dissolution of BPA in natural water bodies. The results are beneficial to better understand the pH dependent distribution of BPA in aquatic environments.


Subject(s)
Benzhydryl Compounds/chemistry , Humic Substances/analysis , Models, Chemical , Phenols/chemistry , Water Pollutants, Chemical/chemistry , Calorimetry , Hydrogen Bonding , Hydrogen-Ion Concentration , Hydrophobic and Hydrophilic Interactions , Thermodynamics
7.
Sci Total Environ ; 677: 502-510, 2019 Aug 10.
Article in English | MEDLINE | ID: mdl-31063893

ABSTRACT

Bisphenol A (BPA) in wastewater has high risks of causing biological feminization. During the wastewater treatment process, large amounts of BPA are accumulated in activated sludge. However, the mechanisms of BPA interacted with activated sludge are still unclear. Especially, the roles of extracellular polymeric substances (EPS), which are major components of activated sludge, in the removal of BPA have never been concerned. In this study, the binding interactions between sludge EPS and BPA are explored combining fluorescence spectroscopy and dynamic light scattering. The thermodynamic mechanisms driving the binding behavior of BPA to EPS are illustrated by isothermal titration calorimetry. The results indicate that the binding interaction between BPA and EPS is spontaneous. BPA mainly binds with the proteins of EPS by hydrophobic association. The random-coiled structure of EPS transforms into relatively condensed cores after binding with BPA. A neutral pH, high ionic strength, and high temperature promote the binding process, facilitating to stabilize BPA in sludge EPS. This study provides new insights into the roles of sludge EPS in the migration and removal of BPA in activated sludge system.


Subject(s)
Benzhydryl Compounds/chemistry , Extracellular Polymeric Substance Matrix/chemistry , Phenols/chemistry , Sewage/analysis , Water Pollutants, Chemical/chemistry , Chromatography, Gel , Dynamic Light Scattering , Hydrogen-Ion Concentration , Ions/analysis , Spectrometry, Fluorescence , Spectroscopy, Fourier Transform Infrared , Temperature , Thermodynamics , Wastewater/analysis
8.
J Environ Manage ; 232: 219-225, 2019 Feb 15.
Article in English | MEDLINE | ID: mdl-30476683

ABSTRACT

Triclosan (TCS) contaminant has aroused wide concerns due to the high risk of converting into toxic dioxin in aquatic environments. During the wastewater treatment process, considerable amounts of TCS are accumulated in activated sludge but the mechanisms are still unclear. Especially, roles of extracellular polymeric substances (EPS), the main components of activated sludge, in TCS removal have never been addressed. In this work, the binding properties of loosely-bound EPS (LB-EPS) and tightly-bound EPS (TB-EPS) of activated sludge to TCS are investigated by fluorescence quenching approach. The influences of aquatic conditions including solution pH, ionic strength and temperature on the interactions between EPS and TCS are explored. Possible interaction mechanisms are discussed as well as the corresponding environmental implication. Results indicate that binding processes of EPS to TCS are exothermic mainly driven by the enthalpy changes. The proteins components in EPS dominate the interactions between EPS and TCS by hydrogen bond and hydrophobic interaction. The binding strength could be improved under the condition of weak alkaline and relative high ionic strength. Generally, LB-EPS exhibit stronger binding ability to TCS than TB-EPS under neutral environment, playing more crucial roles in the binding process. This work highlights the important contributions of EPS to TCS removal, that is beneficial to comprehensively understand the migration of TCS in activated sludge system.


Subject(s)
Sewage , Triclosan , Extracellular Polymeric Substance Matrix , Thermodynamics , Wastewater
9.
Article in Chinese | WPRIM (Western Pacific) | ID: wpr-312830

ABSTRACT

<p><b>OBJECTIVE</b>To observe the effect of catgut implantation at acupoint on the content of tumor necrosis factor alpha (TNF-alpha), and to explore its mechanism for treatment of ankylosing spondylitis (AS).</p><p><b>METHODS</b>Seventy-four AS patients were randomly assigned to the observation group and the control group by digit random table, 37 in each group. Patients in the control group took Sulfasalazine Enteric-coated Tablet (SECT), 0.5 g each time, three times daily for 3 months. Those in the observation group additionally received catgut implantation at acupoint for 3 months. Changes of visual analogue scale (VAS), Schober test, pillow wall distance, thoracic activity, erythrocyte sedimentation rate (ESR), C reactive protein (CRP), and TNF-alpha were compared after 3 months of treatment.</p><p><b>RESULTS</b>There was obvious change in VAS, Schober test, pillow wall distance, thoracic activity, ESR, CRP, and TNF-alpha after treatment in the both groups, showing statistical difference when compared with before treatment (P < 0.05, P < 0.01). The aforesaid indices were obviously improved after treatment in the observation group (P < 0.05, P < 0.01).</p><p><b>CONCLUSION</b>Catgut implantation at acupoint, as an assistant therapy, could significantly improve clinical symptoms and signs, decrease the level of TNF-alpha, and its effect was superior to that of oral SECT administration alone.</p>


Subject(s)
Adolescent , Adult , Aged , Female , Humans , Male , Middle Aged , Young Adult , Acupuncture Points , Acupuncture Therapy , Spondylitis, Ankylosing , Blood , Therapeutics , Tumor Necrosis Factor-alpha , Blood
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