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1.
Proc Natl Acad Sci U S A ; 119(10): e2116279119, 2022 03 08.
Article in English | MEDLINE | ID: mdl-35238669

ABSTRACT

The warning cytokine interleukin-33 receptor (IL-33R) mediates local inflammatory responses and plays crucial roles in the pathogenesis of immune diseases such as pulmonary fibrosis and rheumatoid arthritis. Whether and how IL-33R is regulated remain enigmatic. Here, we identified ubiquitin-specific protease 38 (USP38) as a negative regulator of IL-33R­mediated signaling. USP38 deficiency promotes interleukin-33 (IL-33)­induced downstream proinflammatory responses in vitro and in vivo. Usp38−/− mice are more susceptible to inflammatory damage and death and developed more serious pulmonary fibrosis after bleomycin treatment. USP38 is constitutively associated with IL-33R and deconjugates its K27-linked polyubiquitination at K511, resulting in its autophagic degradation. We further show that the E3 ubiquitin ligase tumor necrosis factor receptor­associated factor 6 (TRAF6) catalyzes K27-linked polyubiquitination of IL-33R at K511, and that deficiency of TRAF6 inhibits IL-33­mediated signaling. Our findings suggest that K27-linked polyubiquitination and deubiquitination of IL-33R by TRAF6 and USP38 reciprocally regulate IL-33R level and signaling, which represents a critical mechanism in the regulation of IL-33­triggered lung inflammatory response and pulmonary fibrosis.


Subject(s)
Inflammation/physiopathology , Interleukin-33/physiology , Intracellular Signaling Peptides and Proteins/metabolism , Pulmonary Fibrosis/physiopathology , Ubiquitin-Specific Proteases/metabolism , Autophagy , Down-Regulation , Humans , Inflammation/metabolism , Interleukin-33/metabolism , Pulmonary Fibrosis/chemically induced , Pulmonary Fibrosis/metabolism , Signal Transduction , Ubiquitin-Specific Proteases/genetics , Ubiquitination
2.
Proc Natl Acad Sci U S A ; 119(37): e2207449119, 2022 Sep 13.
Article in English | MEDLINE | ID: mdl-36067325

ABSTRACT

The elementary CuO2 plane sustaining cuprate high-temperature superconductivity occurs typically at the base of a periodic array of edge-sharing CuO5 pyramids. Virtual transitions of electrons between adjacent planar Cu and O atoms, occurring at a rate t/ℏ and across the charge-transfer energy gap [Formula: see text], generate "superexchange" spin-spin interactions of energy [Formula: see text] in an antiferromagnetic correlated-insulator state. However, hole doping this CuO2 plane converts this into a very-high-temperature superconducting state whose electron pairing is exceptional. A leading proposal for the mechanism of this intense electron pairing is that, while hole doping destroys magnetic order, it preserves pair-forming superexchange interactions governed by the charge-transfer energy scale [Formula: see text]. To explore this hypothesis directly at atomic scale, we combine single-electron and electron-pair (Josephson) scanning tunneling microscopy to visualize the interplay of [Formula: see text] and the electron-pair density nP in Bi2Sr2CaCu2O8+x. The responses of both [Formula: see text] and nP to alterations in the distance δ between planar Cu and apical O atoms are then determined. These data reveal the empirical crux of strongly correlated superconductivity in CuO2, the response of the electron-pair condensate to varying the charge-transfer energy. Concurrence of predictions from strong-correlation theory for hole-doped charge-transfer insulators with these observations indicates that charge-transfer superexchange is the electron-pairing mechanism of superconductive Bi2Sr2CaCu2O8+x.

3.
FASEB J ; 37(10): e23160, 2023 10.
Article in English | MEDLINE | ID: mdl-37750502

ABSTRACT

Glioblastoma multiforme (GBM) is the most malignant brain tumor with rapid angiogenesis. How to inhibit GBM angiogenesis is a key problem to be solved. To explore the targets of inhibiting GBM angiogenesis, this study confirmed that the expression of circMTA1 (hsa_circ_0033614) was significantly upregulated in human brain microvascular endothelial cells exposed to glioma cell-conditioned medium (GECs). The expression of circMTA1 in the cytoplasm was significantly higher than that in the nucleus. Upregulated circMTA1 in GECs can promote cell proliferation, migration, and tube formation. Further exploration of the circularization mechanism of circMTA1 confirmed that KHDRBS1 protein can bind to the upstream and downstream flanking sequences of circMTA1 and promote circMTA1 biogenesis by coordinating Alu element pairing. KHDRBS1 upregulated the proliferation, migration, and tube formation of GECs by promoting the biogenesis of circMTA1. CircMTA1 can encode the protein MTA1-134aa by internal ribosome entry site sequence-mediated translation mechanism, and promote the proliferation, migration, and tube formation of GECs through the encoded MTA1-134aa. This study provides a new target for inhibiting angiogenesis in brain GBM and a new strategy for improving the therapeutic efficacy of GBM.


Subject(s)
Brain Neoplasms , Glioblastoma , Glioma , Humans , Glioblastoma/genetics , Endothelial Cells , Alu Elements , Brain Neoplasms/genetics , Cell Cycle Proteins , DNA-Binding Proteins , RNA-Binding Proteins , Adaptor Proteins, Signal Transducing
4.
Pediatr Res ; 95(6): 1543-1552, 2024 May.
Article in English | MEDLINE | ID: mdl-38245633

ABSTRACT

BACKGROUND: Pulmonary fibrosis (PF) is a progressive lung disorder with a high mortality rate; its therapy remains limited due to the inefficiency of drug delivery. In this study, the system of drug delivery of nintedanib (Nin) by exosomes derived from adipose-derived stem cells (ADSCs-Exo, Exo) was developed to effectively deliver Nin to lung lesion tissue to ensure enhanced anti-fibrosis therapy. METHODS: The bleomycin (BLM)-induced PF model was constructed in vivo and in vitro. The effects of Exo-Nin on BLM-induced PF and its regulatory mechanism were examined using RT-qPCR, Western blotting, immunofluorescence, and H&E staining. RESULTS: We found Exo-Nin significantly improved BLM-induced PF in vivo and in vitro compared to Nin and Exo groups alone. Mechanistically, Exo-Nin alleviated fibrogenesis by suppressing endothelial-mesenchymal transition through the down-regulation of the TGF-ß/Smad pathway and the attenuation of oxidative stress in vivo and in vitro. CONCLUSIONS: Utilizing adipose stem cell-derived exosomes as carriers for Nin exhibited a notable enhancement in therapeutic efficacy. This improvement can be attributed to the regenerative properties of exosomes, indicating promising prospects for adipose-derived exosomes in cell-free therapies for PF. IMPACT: The system of drug delivery of nintedanib (Nin) by exosomes derived from adipose-derived stem cells was developed to effectively deliver Nin to lung lesion tissue to ensure enhanced anti-fibrosis therapy. The use of adipose stem cell-derived exosomes as the carrier of Nin may increase the therapeutic effect of Nin, which can be due to the regenerative properties of the exosomes and indicate promising prospects for adipose-derived exosomes in cell-free therapies for PF.


Subject(s)
Bleomycin , Exosomes , Indoles , Pulmonary Fibrosis , Exosomes/metabolism , Exosomes/transplantation , Animals , Indoles/pharmacology , Pulmonary Fibrosis/therapy , Pulmonary Fibrosis/drug therapy , Pulmonary Fibrosis/metabolism , Mice , Adipose Tissue/cytology , Stem Cells/cytology , Disease Models, Animal , Mice, Inbred C57BL , Lung/pathology , Lung/metabolism , Oxidative Stress/drug effects , Transforming Growth Factor beta/metabolism , Humans , Signal Transduction , Male , Drug Delivery Systems
5.
Phytopathology ; 114(3): 618-629, 2024 Mar.
Article in English | MEDLINE | ID: mdl-37889191

ABSTRACT

The dynamic of plant-parasitic nematode populations in soil is closely related to soil microorganisms. Fungi from Heterodera zeae cysts were isolated to explore the phenomenon of decline in the H. zeae population in the soil. Phylogenetic study of partial ITS, BenA, CaM, and RPB2 gene sequences, in addition to morphological investigations, was utilized to identify a nematode-destroying fungus. The nematicidal activity of a novel strain GX1 against H. zeae was assessed in vitro and in the greenhouse. Our findings revealed that strain GX1 is a new species of Talaromyces, named Talaromyces cystophila. It has a strong parasitic and lethal effect on H. zeae cysts, with 91.11% parasitism on cysts at 3 days after treatment. The contents of second-stage juveniles (J2s) and eggs inside the cysts were degraded and formed dense vacuoles, and the damaged eggs could not hatch normally. The spore suspension exhibited high nematophagous activity against nematodes, and fermentation filtrate exhibited marked inhibition of egg hatching and nematicidal activities on J2s. The hatching inhibition rates of eggs exposed to 1 × 108 CFU/ml spore suspensions or 20% 1-week fermentation filtrate (1-WF) for 15 days were 98.56 and 100%, respectively. The mortality of J2s exposed to 1 × 108 CFU/ml spore suspension reached 100% at 24 h; exposure to 50% 2-WF was 98.65 and 100% at 24 and 48 h, respectively. Greenhouse experiments revealed that the spore suspension and fermentation broth considerably decreased H. zeae reproduction by 56.17 to 78.76%. T. cystophila is a potential biocontrol strain with nematophagous and nematicidal activity that deserves attention and application.


Subject(s)
Cysts , Talaromyces , Tylenchida , Tylenchoidea , Animals , Zea mays , Talaromyces/metabolism , Phylogeny , Plant Diseases/prevention & control , Plant Diseases/parasitology , Antinematodal Agents/pharmacology , Soil
6.
Article in English | MEDLINE | ID: mdl-38556382

ABSTRACT

BACKGROUND: Pancreatic cancer is a common malignancy with poor prognosis and limited treatment. Here we aimed to investigate the role of host chromosomal instability (CIN) and tumor microbiome in the prognosis of pancreatic cancer patients. METHODS: One hundred formalin-fixed paraffin-embedded (FFPE) pancreatic cancer samples were collected. DNA extracted from FFPE samples were analyzed by low-coverage whole-genome sequencing (WGS) via a customized bioinformatics workflow named ultrasensitive chromosomal aneuploidy detector. RESULTS: Samples are tested according to the procedure of ultrasensitive chromosomal aneuploidy detector (UCAD). We excluded 2 samples with failed quality control, 1 patient lost to follow-up and 6 dead in the perioperative period. The final 91 patients were admitted for the following analyses. Thirteen (14.3%) patients with higher CIN score had worse overall survival (OS) than those with lower CIN score. The top 20 microbes in pancreatic cancer samples included 15 species of bacteria and 5 species of viruses. Patients with high human herpesvirus (HHV)-7 and HHV-5 DNA reads exhibited worse OS. Furthermore, we classified 91 patients into 3 subtypes. Patients with higher CIN score (n =13) had the worst prognosis (median OS 6.9 mon); patients with lower CIN score but with HHV-7/5 DNA load (n = 24) had worse prognosis (median OS 10.6 mon); while patients with lower CIN score and HHV-7/5 DNA negative (n = 54) had the best prognosis (median OS 21.1 mon). CONCLUSIONS: High CIN and HHV-7/5 DNA load were associated with worse survival of pancreatic cancer. The novel molecular subtypes of pancreatic cancer based on CIN and microbiome had prognostic value.

7.
Proc Natl Acad Sci U S A ; 117(35): 21568-21575, 2020 09 01.
Article in English | MEDLINE | ID: mdl-32817552

ABSTRACT

The DNA sensor cGMP-AMP synthase (cGAS) senses cytosolic microbial or self DNA to initiate a MITA/STING-dependent innate immune response. cGAS is regulated by various posttranslational modifications at its C-terminal catalytic domain. Whether and how its N-terminal unstructured domain is regulated by posttranslational modifications remain unknown. We identified the acetyltransferase KAT5 as a positive regulator of cGAS-mediated innate immune signaling. Overexpression of KAT5 potentiated viral-DNA-triggered transcription of downstream antiviral genes, whereas a KAT5 deficiency had the opposite effects. Mice with inactivated Kat5 exhibited lower levels of serum cytokines in response to DNA virus infection, higher viral titers in the brains, and more susceptibility to DNA-virus-induced death. Mechanistically, KAT5 catalyzed acetylation of cGAS at multiple lysine residues in its N-terminal domain, which promoted its DNA-binding ability. Our findings suggest that KAT5-mediated cGAS acetylation at its N terminus is important for efficient innate immune response to DNA virus.


Subject(s)
DNA Virus Infections/immunology , DNA Viruses/immunology , Lysine Acetyltransferase 5/immunology , Nucleotidyltransferases/immunology , Acetylation , Animals , Cyclic GMP/metabolism , DNA Virus Infections/genetics , DNA Virus Infections/metabolism , DNA Viruses/genetics , Female , HEK293 Cells , HeLa Cells , Host-Pathogen Interactions , Humans , Immunity, Innate , Interferon-beta/immunology , Lysine Acetyltransferase 5/genetics , Lysine Acetyltransferase 5/metabolism , Male , Mice , Mice, Knockout , Nitric Oxide Synthase/genetics , Nitric Oxide Synthase/metabolism , Nucleotidyltransferases/genetics , Nucleotidyltransferases/metabolism , Protein Processing, Post-Translational , Signal Transduction , Viral Proteins/metabolism
8.
Int J Mol Sci ; 24(15)2023 Jul 29.
Article in English | MEDLINE | ID: mdl-37569566

ABSTRACT

Carcinoembryonic antigen (CEA) and carbohydrate antigen 19-9 (CA19-9) are established prognostic biomarkers for patients with gastric cancer. However, their potential as predictive markers for neoadjuvant chemotherapy (NACT) efficacy has not been fully elucidated. METHODS: We conducted a retrospective analysis to determine values of CEA and CA19-9 prior to NACT (pre-NACT) and after NACT (post-NACT) in 399 patients with locally advanced gastric cancer (LAGC) who received intended NACT and surgery. RESULTS: Among the 399 patients who underwent NACT plus surgery, 132 patients (33.1%) had elevated pre-NACT CEA/CA19-9 values. Furthermore, either pre-NACT or post-NACT CEA /CA19-9 levels were significantly associated with prognosis (p = 0.0023) compared to patients with non-elevated levels. Moreover, among the patients, a significant proportion (73/132, 55.3%) achieved normalized CEA/CA19-9 following NACT, which is a strong marker of a favorable treatment response and survival benefits. In addition, the patients with normalized CEA/CA19-9 also had a prolonged survival compared to those who underwent surgery first (p = 0.0140), which may be attributed to the clearance of micro-metastatic foci. Additionally, the magnitude of CEA/CA19-9 changes did not exhibit a statistically significant prognostic value. CONCLUSIONS: Normalization of CEA/CA19-9 is a strong biomarker for the effectiveness of treatment, and can thus be exploited to prolong the long-term survival of patients with LAGC.


Subject(s)
Carcinoembryonic Antigen , Stomach Neoplasms , Humans , CA-19-9 Antigen , Stomach Neoplasms/pathology , Neoadjuvant Therapy , Retrospective Studies , Biomarkers, Tumor , Carbohydrates
9.
Sheng Li Xue Bao ; 75(6): 788-798, 2023 Dec 25.
Article in Zh | MEDLINE | ID: mdl-38151344

ABSTRACT

Chronic inflammatory reaction has been established as an important sign of the occurrence and development of diabetes mellitus (DM), accompanied by the production of a large number of inflammatory factors, thus aggravating the disease progression. As an important non-invasive intervention measure to inhibit inflammation, exercise plays a very important role in the amelioration of DM. NOD-like receptor protein 3 (NLRP3) inflammasome, a regulatory factor of inflammatory response, can induce a variety of inflammatory cascades and cell death, which are closely related to glucose uptake and dyslipidemia regulation. The development of DM can be postponed with exercise. Previous studies have reported the effects of NLRP3 inflammasome on DM, but the crucial role of exercise in this process remains unclear. Therefore, this paper reviews the research progress on the improving effects of exercise intervention on the symptoms of DM by mediating NLRP3 inflammasome, providing a novel theoretical foundation for understanding the prevention and treatment of DM through exercise.


Subject(s)
Diabetes Mellitus , Inflammasomes , Humans , Inflammasomes/metabolism , NLR Family, Pyrin Domain-Containing 3 Protein/metabolism , NLR Proteins , Inflammation , Exercise Therapy
10.
Sheng Li Xue Bao ; 75(2): 303-315, 2023 Apr 25.
Article in Zh | MEDLINE | ID: mdl-37089104

ABSTRACT

Interleukin 27 (IL-27) is a pleiotropic cytokine that is involved in the regulation of the body's innate and adaptive immunity. Previous studies have shown that IL-27 mediates a variety of inflammatory responses in vivo. With the development of animal models and technical tools, several studies have shown that it is also closely associated with autoimmune diseases and other immune related diseases, and is considered as an important candidate for the treatment of viral disease, autoimmune diseases, tumors and obesity. Therefore, this paper reviews recent progress on the role of IL-27 in acquired immunodeficiency syndrome (AIDS), rheumatoid arthritis, tumors and obesity, with the aim of providing new ideas for the treatment of immune related diseases.


Subject(s)
Arthritis, Rheumatoid , Autoimmune Diseases , Interleukin-27 , Neoplasms , Animals , Cytokines
11.
Bioinformatics ; 37(3): 429-430, 2021 04 20.
Article in English | MEDLINE | ID: mdl-32717036

ABSTRACT

SUMMARY: Dysfunctional regulations of gene expression programs relevant to fundamental cell processes can drive carcinogenesis. Therefore, systematically identifying dysregulation events is an effective path for understanding carcinogenesis and provides insightful clues to build predictive signatures with mechanistic interpretability for cancer precision medicine. Here, we implemented a machine learning-based gene dysregulation analysis framework in an R package, DysRegSig, which is capable of exploring gene dysregulations from high-dimensional data and building mechanistic signature based on gene dysregulations. DysRegSig can serve as an easy-to-use tool to facilitate gene dysregulation analysis and follow-up analysis. AVAILABILITY AND IMPLEMENTATION: The source code and user's guide of DysRegSig are freely available at Github: https://github.com/SCBIT-YYLab/DysRegSig. SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.


Subject(s)
Neoplasms , Software , Humans , Machine Learning , Neoplasms/genetics
12.
Nat Mater ; 20(11): 1480-1484, 2021 Nov.
Article in English | MEDLINE | ID: mdl-34462570

ABSTRACT

The most essential characteristic of any fluid is the velocity field, and this is particularly true for macroscopic quantum fluids1. Although rapid advances2-7 have occurred in quantum fluid velocity field imaging8, the velocity field of a charged superfluid-a superconductor-has never been visualized. Here we use superconducting-tip scanning tunnelling microscopy9-11 to image the electron-pair density and velocity fields of the flowing electron-pair fluid in superconducting NbSe2. Imaging of the velocity fields surrounding a quantized vortex12,13 finds electronic fluid flow with speeds reaching 10,000 km h-1. Together with independent imaging of the electron-pair density via Josephson tunnelling, we visualize the supercurrent density, which peaks above 3 × 107 A cm-2. The spatial patterns in electronic fluid flow and magneto-hydrodynamics reveal hexagonal structures coaligned to the crystal lattice and quasiparticle bound states14, as long anticipated15-18. These techniques pave the way for electronic fluid flow visualization studies of other charged quantum fluids.

13.
Metab Brain Dis ; 37(5): 1401-1414, 2022 06.
Article in English | MEDLINE | ID: mdl-35420377

ABSTRACT

Vascular dementia (VaD) is the second cause of dementia after Alzheimer's disease. Ligustilide (LIG) is one of the main active ingredients of traditional Chinese medicines, such as Angelica. Studies have reported that LIG could protect against VaD. However, the mechanism is still confused. In this study, we employed a bilateral common carotid artery occlusion rat model to study. LIG (20 or 40 mg/kg/day) and Nimodipine (20 mg/kg) were orally administered to the VaD rats for four weeks. Morris water maze test showed that LIG effectively ameliorated learning and memory impairment in VaD rats. LIG obviously reduced neuronal oxidative stress damage and the level of homocysteine in the brain of VaD rats. Western blot results showed that pro-apoptotic protein Bax and cleaved caspase 3 increased and anti-apoptotic protein Bcl-2 decreased in the hippocampi of VaD rats. But after LIG treatment, these changes were reversed. Moreover, Nissl staining result showed that LIG could reduce neuronal degeneration in VaD rats. Furthermore, LIG enhanced the expressions of P-AMPK and Sirtuin1(SIRT1) in VaD rats. In conclusion, these studies indicated that LIG could ameliorate cognitive impairment in VaD rats, which might be related to AMPK/SIRT1 pathway activation.


Subject(s)
Cognitive Dysfunction , Dementia, Vascular , 4-Butyrolactone/analogs & derivatives , AMP-Activated Protein Kinases , Animals , Cognitive Dysfunction/drug therapy , Dementia, Vascular/drug therapy , Disease Models, Animal , Maze Learning , Rats , Sirtuin 1
14.
Proc Natl Acad Sci U S A ; 116(40): 20063-20069, 2019 10 01.
Article in English | MEDLINE | ID: mdl-31527250

ABSTRACT

Upon cytosolic viral DNA stimulation, cGMP-AMP synthase (cGAS) catalyzes synthesis of 2'3'cGMP-AMP (cGAMP), which binds to the adaptor protein MITA (mediator of IRF3 activation, also called STING, stimulator of IFN genes) and induces innate antiviral response. How the activity of MITA/STING is regulated to avoid excessive innate immune response is not fully understood. Here we identified the tyrosine-protein phosphatase nonreceptor type (PTPN) 1 and 2 as MITA/STING-associated proteins. PTPN1 and PTPN2 are associated with MITA/STING following viral infection and dephosphorylate MITA/STING at Y245. Dephosphorylation of MITA/STING leads to its degradation via the ubiquitin-independent 20S proteasomal pathway, which is dependent on the intrinsically disordered region (IDR) of MITA/STING. Deficiencies of PTPN1 and PTPN2 enhance viral DNA-induced transcription of downstream antiviral genes and innate antiviral response. Our findings reveal that PTPN1/2-mediated dephosphorylation of MITA/STING and its degradation by the 20S proteasomal pathway is an important regulatory mechanism of innate immune response to DNA virus.


Subject(s)
Immunity, Innate , Membrane Proteins/metabolism , Proteasome Endopeptidase Complex/metabolism , Protein Tyrosine Phosphatase, Non-Receptor Type 1/metabolism , Protein Tyrosine Phosphatase, Non-Receptor Type 2/metabolism , Virus Diseases/immunology , Virus Diseases/metabolism , Animals , Biomarkers , DNA, Viral/genetics , DNA, Viral/metabolism , Host-Pathogen Interactions/immunology , Humans , Immunohistochemistry , Mice , Phosphorylation , Protein Binding , Proteolysis , Signal Transduction , Virus Diseases/virology
15.
Molecules ; 27(22)2022 Nov 09.
Article in English | MEDLINE | ID: mdl-36431786

ABSTRACT

Multidrug-resistant bacterial infections mediated by metallo-ß-lactamases (MßLs) have grown into an emergent health threat, and development of novel antimicrobials is an ideal strategy to combat the infections. Herein, a novel vancomycin derivative Vb was constructed by conjugation of triazolylthioacetamide and vancomycin molecules, characterized by reverse-phase high performance liquid chromatography (HPLC) and confirmed by matrix-assisted laser desorption/ionization-time of flight mass spectrometry (MALDI-TOF MS). The biological assays revealed that Vb effectively inhibited S. aureus and methicillin-resistant S. aureus (MRSA), gradually increased the antimicrobial effect of ß-lactam antibiotics (cefazolin, meropenem and penicillin G) and exhibited a dose-dependent synergistic antibacterial effect against eight resistant strains tested, which was confirmed by the time-kill curves determination. Most importantly, Vb increased the antimicrobial effect of meropenem against the clinical isolates EC08 and EC10 and E. coli producing ImiS and CcrA, resulting in a 4- and 8-fold reduction in MIC values, respectively, at a dose up to 32 µg/mL. This work offers a promising scaffold for the development of MßLs inhibitors, specifically antimicrobials for clinically drug-resistant isolates.


Subject(s)
Methicillin-Resistant Staphylococcus aureus , Vancomycin , Vancomycin/pharmacology , Staphylococcus aureus , beta-Lactamases , Meropenem/pharmacology , Microbial Sensitivity Tests , Escherichia coli , Bacteria
16.
Zhongguo Zhong Yao Za Zhi ; 47(19): 5158-5170, 2022 Oct.
Article in Zh | MEDLINE | ID: mdl-36472022

ABSTRACT

Bruceae Fructus is a Chinese herbal medicine with the chemical constituents mainly including Brucea javanica oil, quassinoids, flavonoids, steroids, triterpenoids, and alkaloids. Modern research demonstrates that Bruceae Fructus has anti-tumor, anti-malaria, anti-inflammatory, and lipid-lowering activities. This paper introduces the resource distribution, chemical constituents, and pharmacological activities of Bruceae Fructus. Further, according to the concept of quality marker(Q-marker), this paper predicts the Q-markers of Bruceae Fructus from the specificity of chemical components, pharmaceutical activity, measurability of chemical constituents, compatibility, and clinical efficacy, aiming to provide a theoretical basis for establishing the quality standard of Bruceae Fructus.


Subject(s)
Drugs, Chinese Herbal , Quassins , Fruit , Drugs, Chinese Herbal/pharmacology , Flavonoids , Biomarkers
17.
Angew Chem Int Ed Engl ; 61(51): e202214147, 2022 Dec 19.
Article in English | MEDLINE | ID: mdl-36328976

ABSTRACT

Strategies on the construction of enantiomerically pure silicon-stereogenic silanes generally relies on desymmetrization of prochiral and symmetric substrates. However, dynamic kinetic asymmetric transformations of organosilicon compounds have remained underdeveloped and unforeseen owing to a lack of an effective method for deracemization of the static silicon stereocenters. Here we report the first Rh-catalyzed dynamic kinetic asymmetric intramolecular hydrosilylation (DyKAH) with "silicon-centered" racemic hydrosilanes that enables the facile preparation of silicon-stereogenic benzosiloles in good yields and excellent enantioselectivities. The special rhodium catalyst controlled by non-diastereopure-type mixed phosphine-phosphoramidite ligand with axial chirality and multiple stereocenters can induce enantioselectivity efficiently in this novel DyKAH reaction. Density functional theory (DFT) calculations suggest that the amide moiety in chiral ligand plays important role in facilitating the SN 2 substitution of chloride ion to realize the chiral inversion of silicon center.

18.
Exp Cell Res ; 388(2): 111878, 2020 03 15.
Article in English | MEDLINE | ID: mdl-32004504

ABSTRACT

Occupational exposure to silica dust particles was the major cause of pulmonary fibrosis, and many miRNAs have been demonstrated to regulate target mRNAs in silicosis. In the present study, we found that a decreasing level of miR-411-3p in silicosis rats and lung fibroblasts induced by TGF-ß1. Enlargement of miR-411-3p could inhibit the cell proliferation and migration in lung fibroblasts with TGF-ß1 treatment and attenuate lung fibrosis in silicotic mice. In addition, a mechanistic study showed that miR-411-3p exert its inhibitory effect on Smad ubiquitination regulatory factor 2 (Smurf2) expression and decrease ubiquitination degradation of Smad7 regulated by smurf2, result in blocking of TGF-ß/Smad signaling. We proposed that increased expression of miR-411-3p abrogates silicosis by blocking activation of TGF-ß/Smad signaling through decreasing ubiquitination degradation effect of smurf2 on Smad7.


Subject(s)
Gene Expression Regulation , MicroRNAs/genetics , Pulmonary Fibrosis/prevention & control , Silicon Dioxide/toxicity , Silicosis/prevention & control , Transforming Growth Factor beta/metabolism , Ubiquitin-Protein Ligases/metabolism , Animals , Male , Pulmonary Fibrosis/chemically induced , Pulmonary Fibrosis/genetics , Pulmonary Fibrosis/pathology , Rats , Rats, Wistar , Silicosis/genetics , Silicosis/pathology , Transforming Growth Factor beta/genetics , Ubiquitin-Protein Ligases/genetics
19.
Nano Lett ; 20(11): 8001-8007, 2020 Nov 11.
Article in English | MEDLINE | ID: mdl-32985892

ABSTRACT

The quantum anomalous Hall (QAH) effect appears in ferromagnetic topological insulators (FMTIs) when a Dirac mass gap opens in the spectrum of the topological surface states (SSs). Unaccountably, although the mean mass gap can exceed 28 meV (or ∼320 K), the QAH effect is frequently only detectable at temperatures below 1 K. Using atomic-resolution Landau level spectroscopic imaging, we compare the electronic structure of the archetypal FMTI Cr0.08(Bi0.1Sb0.9)1.92Te3 to that of its nonmagnetic parent (Bi0.1Sb0.9)2Te3, to explore the cause. In (Bi0.1Sb0.9)2Te3, we find spatially random variations of the Dirac energy. Statistically equivalent Dirac energy variations are detected in Cr0.08(Bi0.1Sb0.9)1.92Te3 with concurrent but uncorrelated Dirac mass gap disorder. These two classes of SS electronic disorder conspire to drastically suppress the minimum mass gap to below 100 µeV for nanoscale regions separated by <1 µm. This fundamentally limits the fully quantized anomalous Hall effect in Sb2Te3-based FMTI materials to very low temperatures.

20.
Yi Chuan ; 43(10): 924-929, 2021 Oct 20.
Article in English | MEDLINE | ID: mdl-34702704

ABSTRACT

In recent years, with the development of various high-throughput omics based biological technologies (BT), biomedical research began to enter the era of big data. In the face of high-dimensional, multi-domain and multi-modal biomedical big data, scientific research requires a new paradigm of data intensive scientific research. The vigorous development of cutting-edge information technologies (IT) such as cloud computing, blockchain and artificial intelligence provides technical means for the practice of this new research paradigm. Here,we describe the application of such cutting-edge information technologies in biomedical big data, and propose a forward-looking prospect for the construction of a new paradigm supporting environment for data intensive scientific research. We expect to establish a new research scheme and new scientific research paradigm integrating BT & IT technology, which can finally promote the great leap forward development of biomedical research.


Subject(s)
Biomedical Research , Information Technology , Artificial Intelligence , Big Data , Cloud Computing
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