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1.
J Neurosci ; 43(25): 4559-4579, 2023 06 21.
Artigo em Inglês | MEDLINE | ID: mdl-37225434

RESUMO

Previous studies have shown the essential roles of O-GlcNAc transferase (Ogt) and O-GlcNAcylation in neuronal development, function and neurologic diseases. However, the function of Ogt and O-GlcNAcylation in the adult cerebellum has not been well elucidated. Here, we have found that cerebellum has the highest level of O-GlcNAcylation relative to cortex and hippocampus of adult male mice. Specific deletion of Ogt in granule neuron precursors (GNPs) induces abnormal morphology and decreased size of the cerebellum in adult male Ogt deficient [conditional knock-out (cKO)] mice. Adult male cKO mice show the reduced density and aberrant distribution of cerebellar granule cells (CGCs), the disrupted arrangement of Bergman glia (BG) and Purkinje cells. In addition, adult male cKO mice exhibit aberrant synaptic connection, impaired motor coordination, and learning and memory abilities. Mechanistically, we have identified G-protein subunit α12 (Gα12) is modified by Ogt-mediated O-GlcNAcylation. O-GlcNAcylation of Gα12 facilitates its binding to Rho guanine nucleotide exchange factor 12 (Arhgef12) and consequently activates RhoA/ROCK signaling. RhoA/ROCK pathway activator LPA can rescue the developmental deficits of Ogt deficient CGCs. Therefore, our study has revealed the critical function and related mechanisms of Ogt and O-GlcNAcylation in the cerebellum of adult male mice.SIGNIFICANCE STATEMENT Cerebellar function are regulated by diverse mechanisms. To unveil novel mechanisms is critical for understanding the cerebellar function and the clinical therapy of cerebellum-related diseases. In the present study, we have shown that O-GlcNAc transferase gene (Ogt) deletion induces abnormal cerebellar morphology, synaptic connection, and behavioral deficits of adult male mice. Mechanistically, Ogt catalyzes O-GlcNAcylation of Gα12, which promotes the binding to Arhgef12, and regulates RhoA/ROCK signaling pathway. Our study has uncovered the important roles of Ogt and O-GlcNAcylation in regulating cerebellar function and cerebellum-related behavior. Our results suggest that Ogt and O-GlcNAcylation could be potential targets for some cerebellum-related diseases.


Assuntos
Subunidades alfa G12-G13 de Proteínas de Ligação ao GTP , Transdução de Sinais , Camundongos , Masculino , Animais , Subunidades alfa G12-G13 de Proteínas de Ligação ao GTP/metabolismo , N-Acetilglucosaminiltransferases/genética , Camundongos Knockout
2.
Macromol Rapid Commun ; 45(9): e2300685, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38339795

RESUMO

The air filtration materials with high efficiency, low resistance, and extra antibacterial property are crucial for personal health protection. Herein, a tree-like polyvinylidene fluoride (PVDF) nanofibrous membrane with hierarchical structure (trunk fiber of 447 nm, branched fiber of 24.7 nm) and high filtration capacity is demonstrated. Specifically, 2-hydroxypropyl trimethyl ammonium chloride terminated hyperbranched polymer (HBP-HTC) with near-spherical three-dimensional molecular structure and adjustable terminal positive groups is synthesized as an additive for PVDF electrospinning to enhance the jet splitting and promote the formation of branched ultrafine nanofibers, achieving a coverage rate of branched nanofibers over 90% that is superior than small molecular quaternary ammonium salts. The branched nanofibers network enhances mechanical properties and filtration efficiency (99.995% for 0.26 µm sodium chloride particles) of the PVDF/HBP-HTC membrane, which demonstrates reduced pressure drop (122.4 Pa) and a quality factor up to 0.083 Pa-1 on a 40 µm-thick sample. More importantly, the numerous quaternary ammonium salt groups of HBP-HTC deliver excellent antibacterial properties to the PVDF membranes. Bacterial inhibitive rate of 99.9% against both S. aureus and E. coli is demonstrated in a membrane with 3.0 wt% HBP-HTC. This work provides a new strategy for development of high-efficiency and antibacterial protection products.


Assuntos
Antibacterianos , Escherichia coli , Nanofibras , Polímeros , Polivinil , Staphylococcus aureus , Nanofibras/química , Antibacterianos/farmacologia , Antibacterianos/química , Antibacterianos/síntese química , Escherichia coli/efeitos dos fármacos , Staphylococcus aureus/efeitos dos fármacos , Polivinil/química , Polímeros/química , Polímeros/farmacologia , Polímeros/síntese química , Membranas Artificiais , Testes de Sensibilidade Microbiana , Filtros de Ar , Compostos de Amônio Quaternário/química , Compostos de Amônio Quaternário/farmacologia , Filtração/métodos , Tamanho da Partícula , Polímeros de Fluorcarboneto
3.
Phys Chem Chem Phys ; 26(26): 18196-18204, 2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-38904087

RESUMO

The Zr-2.5Nb alloy is a typical pressure tube material in heavy water nuclear reactors, and an increase of hydrogen isotope content in the alloy during service can pose major safety risks; hot vacuum extraction-mass spectrometry is an efficient method for evaluating hydrogen isotope concentrations in the Zr-2.5Nb alloy. This work investigates the kinetics and thermodynamic properties of deuterium (D) absorption and desorption of the Zr-2.5Nb alloy using the constant volume adsorption method and the hot vacuum extraction method. In addition to the previously reported volume contraction model, it was observed that at 600 °C and above, the reaction between D2 and Zr-2.5Nb is dominated by diffusion, while the reaction is predominantly influenced by surface adsorption and dissociation below 600 °C. Phase transition sequence of Zr-2.5Nb deuterides during non-isothermal desorption was established using quantitatively calibrated thermal desorption spectra combined with the phase transition process of deuteride decomposition. These results can provide important references for optimizing the process parameters of the hot vacuum extraction-mass spectrometry method.

4.
Bioorg Chem ; 147: 107374, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38636433

RESUMO

The incidence of idiopathic pulmonary fibrosis (IPF) has been steadily increasing each year, posing significant challenges in its treatment. In this study, we conducted the design and synthesis of 23 new inhibitors that specifically target the TGF-ß1/Smad3 pathway. Initially, we employed a cell model of TGF-ß-induced pulmonary fibrosis, using cell survival rate and HYP expression as indicators to identify the potent ingredient 5aa, which demonstrated significant anti-pulmonary fibrosis activity. Subsequently, we induced mice with bleomycin (BLM) to establish an experimental animal model of pulmonary fibrosis, and evaluated the pharmacodynamics of 5aa in vivo against pulmonary fibrosis. The alterations in HYP and collagen levels in BLM-induced pulmonary fibrosis mice were analyzed using ELISA and immunohistochemistry techniques. The results indicated that compound 5aa effectively suppressed the fibrotic response induced by TGF-ß1, inhibited the expression of the fibrotic marker α-SMA, and hindered the EMT process in NIH3T3 cells. Additionally, oral administration of 5aa demonstrated significant therapeutic effects in a mouse model of IPF, comparable to the established drug Nintedanib. Moreover, compound 5aa exhibited higher bioavailability in vivo compared to Nintedanib. These collective outcomes suggest that 5aa holds promise as a potential inhibitor of TGF-ß1/Smad3 signaling for the treatment of IPF.


Assuntos
Fibrose Pulmonar Idiopática , Transdução de Sinais , Proteína Smad3 , Fator de Crescimento Transformador beta1 , Animais , Proteína Smad3/metabolismo , Proteína Smad3/antagonistas & inibidores , Fibrose Pulmonar Idiopática/tratamento farmacológico , Fibrose Pulmonar Idiopática/patologia , Fibrose Pulmonar Idiopática/induzido quimicamente , Fator de Crescimento Transformador beta1/metabolismo , Fator de Crescimento Transformador beta1/antagonistas & inibidores , Camundongos , Transdução de Sinais/efeitos dos fármacos , Estrutura Molecular , Humanos , Bleomicina , Relação Estrutura-Atividade , Camundongos Endogâmicos C57BL , Células NIH 3T3 , Relação Dose-Resposta a Droga , Masculino
5.
Bioorg Chem ; 146: 107313, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38554675

RESUMO

A series of new deuterated and non-deuterated N2, N4-diphenylpyridine - 2,4-diamine derivatives were synthesized and evaluated as EGFR C797S-mediated resistance inhibitors. Most of these compounds exhibited potent antiproliferative activity against Baf3-EGFR L858R/T790M/C797S and Baf3-EGFR Del19/T790M/C797S cancel cell lines, with IC50 values in the nanomolar concentration range. Among them, compound 14l represented the most active compound with IC50 values of 8-11 nM. Interestingly, metabolic stability assay with rat liver microsomes indicated that the half-life of the deuterated derivative 14o was significantly increased compared to that of 14l. In xenograft mice models, 14o inhibited tumor growth with excellent inhibitory rate of 75.1 % at the dosage of 40 mg/kg, comparing 73.2 % of the TGI with its non-deuterated compound 14l, at a dosage of 80 mg/kg. Mechanism studies revealed that 14o was a potent EGFR L858R/T790M/C797S and EGFR Del19/T790M/C797S kinase inhibitor, which could downregulate the protein phosphorylation of EGFR and m-TOR signaling pathways, arrest cell cycle at G2/M phase by affecting the expression of CDC25C, and promote cell apoptosis by regulating the expression of cleaved caspase-3. In summary, 14o could serve as a promising deuterated compound for the development of highly efficient anticancer agents.


Assuntos
Antineoplásicos , Neoplasias Pulmonares , Humanos , Camundongos , Ratos , Animais , Receptores ErbB , Neoplasias Pulmonares/tratamento farmacológico , Mutação , Inibidores de Proteínas Quinases/uso terapêutico , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Resistencia a Medicamentos Antineoplásicos , Linhagem Celular Tumoral
6.
Cancer Sci ; 114(12): 4583-4595, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37752684

RESUMO

Amplification of amino acids synthesis is reported to promote tumorigenesis. The serine/glycine biosynthesis pathway is a reversible conversion of serine and glycine catalyzed by cytoplasmic serine hydroxymethyltransferase (SHMT)1 and mitochondrial SHMT2; however, the role of SHTM1 in renal cell carcinoma (RCC) is still unclear. We found that low SHMT1 expression is correlated with poor survival of RCC patients. The in vitro study showed that overexpression of SHMT1 suppressed RCC proliferation and migration. In the mouse tumor model, SHMT1 significantly retarded RCC tumor growth. Furthermore, by gene network analysis, we found several SHMT1-related genes, among which homeobox D8 (HOXD8) was identified as the SHMT1 regulator. Knockdown of HOXD8 decreased SHMT1 expression, resulting in faster RCC growth, and rescued the SHMT1 overexpression-induced cell migration defects. Additionally, ChIP assay found the binding site of HOXD8 to SHMT1 promoter was at the -456~-254 bp region. Taken together, SHMT1 functions as a tumor suppressor in RCC. The transcription factor HOXD8 can promote SHMT1 expression and suppress RCC cell proliferation and migration, which provides new mechanisms of SHMT1 in RCC tumor growth and might be used as a potential therapeutic target candidate for clinical treatment.


Assuntos
Carcinoma de Células Renais , Neoplasias Renais , Animais , Humanos , Camundongos , Carcinoma de Células Renais/genética , Linhagem Celular Tumoral , Proliferação de Células/genética , Glicina , Glicina Hidroximetiltransferase/genética , Glicina Hidroximetiltransferase/química , Glicina Hidroximetiltransferase/metabolismo , Proteínas de Homeodomínio/genética , Neoplasias Renais/genética , Serina/metabolismo , Fatores de Transcrição
7.
Hum Mol Genet ; 31(1): 57-68, 2021 12 17.
Artigo em Inglês | MEDLINE | ID: mdl-34346496

RESUMO

Ogt-mediated O-GlcNAcylation is enriched in the nervous system and involves in neuronal development, brain function and neurological diseases. However, the roles of Ogt and O-GlcNAcylation in embryonic neurogenesis have remained largely unknown. Here, we show that Ogt is highly expressed in embryonic brain, and Ogt depletion reduces the proliferation of embryonic neural stem cells and migration of new born neurons. Ogt depletion in cultured hippocampal neurons impairs neuronal maturation, including reduced dendritic numbers and length, and immature development of spines. Mechanistically, Ogt depletion decreases the activity of Wnt/ß-catenin signaling. Ectopic ß-catenin rescues neuronal developmental deficits caused by Ogt depletion. Ogt also regulates human cortical neurogenesis in forebrain organoids derived from induced pluripotent stem cells. Our findings reveal the essential roles and mechanisms of Ogt-mediated O-GlcNAc modification in regulating mammalian neuronal development.


Assuntos
N-Acetilglucosaminiltransferases , beta Catenina , Animais , Humanos , Mamíferos , N-Acetilglucosaminiltransferases/genética , Neurogênese/genética , Neurônios , beta Catenina/genética
8.
Virol J ; 20(1): 135, 2023 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-37349792

RESUMO

OBJECTIVE: To isolate a prevalent G9P[8] group A rotavirus (RVA) (N4006) in China and investigate its genomic and evolutionary characteristics, with the goal of facilitating the development of a new rotavirus vaccine. METHODS: The RVA G9P[8] genotype from a diarrhea sample was passaged in MA104 cells. The virus was evaluated by TEM, polyacrylamide gel electrophoresis, and indirect immunofluorescence assay. The complete genome of virus was obtained by RT-PCR and sequencing. The genomic and evolutionary characteristics of the virus were evaluated by nucleic acid sequence analysis with MEGA ver. 5.0.5 and DNASTAR software. The neutralizing epitopes of VP7 and VP4 (VP5* and VP8*) were analyzed using BioEdit ver. 7.0.9.0 and PyMOL ver. 2.5.2. RESULTS: The RVA N4006 (G9P[8] genotype) was adapted in MA104 cells with a high titer (105.5 PFU/mL). Whole-genome sequence analysis showed N4006 to be a reassortant rotavirus of Wa-like G9P[8] RVA and the NSP4 gene of DS-1-like G2P[4] RVA, with the genotype constellation G9-P[8]-I1-R1-C1-M1-A1-N1-T1-E2-H1 (G9P[8]-E2). Phylogenetic analysis indicated that N4006 had a common ancestor with Japanese G9P[8]-E2 rotavirus. Neutralizing epitope analysis showed that VP7, VP5*, and VP8* of N4006 had low homology with vaccine viruses of the same genotype and marked differences with vaccine viruses of other genotypes. CONCLUSION: The RVA G9P[8] genotype with the G9-P[8]-I1-R1-C1-M1-A1-N1-T1-E2-H1 (G9P[8]-E2) constellation predominates in China and may originate from reassortment between Japanese G9P[8] with Japanese DS-1-like G2P[4] rotaviruses. The antigenic variation of N4006 with the vaccine virus necessitates an evaluation of the effect of the rotavirus vaccine on G9P[8]-E2 genotype rotavirus.


Assuntos
Infecções por Rotavirus , Vacinas contra Rotavirus , Rotavirus , Humanos , Infecções por Rotavirus/epidemiologia , Filogenia , Genoma Viral , Genômica , Genótipo
9.
Bioorg Chem ; 138: 106653, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37302317

RESUMO

For non-small cell lung cancer patients with dual mutations in EGFR and ALK, there are currently no effective therapies. Consequently, novel EGFR/ALK dual-target inhibitors are urgently needed for the treatment of NSCLC. Here, we designed a series of highly effective small molecule dual inhibitors of ALK and EGFR. The biological evaluation highlighted that most of these new compounds could effectively inhibit both ALK and EGFR in enzymatic and cellular assays. Compound (+)-8l was investigated for its antitumor properties, and it was found that (+)-8l blocked the phosphorylation of EGFR and ALK induced by ligands and inhibited phosphorylation-ERK and phosphorylation-AKT induced by ligands. Furthermore, (+)-8l also induces apoptosis and G0/G1 cell cycle arrest in cancer cells and inhibits proliferation, migration, and invasion. Notably, (+)-8l significantly suppressed tumor growth in the H1975 cell-inoculated xenograft model (20 mg/kg/d, TGI: 96.11%), PC9 cell-inoculated xenograft model (20 mg/kg/d, TGI: 96.61%) and EML4 ALK-Baf3 cell-inoculated xenograft model (30 mg/kg/d, TGI: 80.86%). These results highlight the differentiated potential of (+)-8l to inhibit ALK rearrangement and EGFR mutation in NSCLC.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Humanos , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Ligantes , Receptores ErbB , Fosforilação , Mutação , Inibidores de Proteínas Quinases/farmacologia , Inibidores de Proteínas Quinases/química , Linhagem Celular Tumoral , Proteínas de Fusão Oncogênica/genética , Proteínas de Fusão Oncogênica/metabolismo
10.
Molecules ; 28(5)2023 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-36903251

RESUMO

ALK-positive NSCLC coexisting with EGFR mutations is a frequently occurring clinical phenomenon. Targeting ALK and EGFR simultaneously may be an effective way to treat these cancer patients. In this study, we designed and synthesized ten new dual-target EGFR/ALK inhibitors. Among them, the optimal compound 9j exhibited good activity with IC50 values of 0.07829 ± 0.03 µM and 0.08183 ± 0.02 µM against H1975 (EGFR T790M/L858R) and H2228 (EML4-ALK) cells, respectively. Immunofluorescence assays indicated that the compound could simultaneously inhibit the expression of phosphorylated EGFR and ALK proteins. A kinase assay demonstrated that compound 9j could inhibit both EGFR and ALK kinases; thus, exerting an antitumor effect. Additionally, compound 9j induced apoptosis in a dose-dependent manner and inhibited the invasion and migration of tumor cells. All of these results indicate that 9j is worthy of further study.


Assuntos
Antineoplásicos , Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Humanos , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Receptores ErbB/metabolismo , Receptores Proteína Tirosina Quinases , Neoplasias Pulmonares/tratamento farmacológico , Inibidores de Proteínas Quinases/farmacologia , Mutação , Apoptose , Linhagem Celular Tumoral , Proliferação de Células , Antineoplásicos/farmacologia
11.
Liver Int ; 42(8): 1836-1848, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35567760

RESUMO

BACKGROUND AND AIMS: Alagille syndrome (ALGS) type 2 caused by mutations in NOTCH2 has genotypic and phenotypic heterogeneity. Diagnosis in some atypical patients with isolated hepatic presentation could be missed. METHODS: Using 2087 patients with paediatric liver manifestations, NOTCH2 allele frequencies, in-silico prediction, protein domains and clinical features were analysed to define the pathogenicity of NOTCH2 variants for diagnosis of ALGS type 2. RESULTS: Among 2087 patients with paediatric liver manifestations, significantly more NOTCH2 variants were absent in gnomAD in patients with elevated γ-glutamyltransferase (GGT) (p = .041). Significantly more NOTCH2 variants which were absent in gnomAD were located in protein functional domains (p = .038). When missense variants were absent in gnomAD and predicted to be pathogenic by at least three out of seven in-silico tools, they were found to be significantly associated with liver manifestations with elevated GGT (p = .003). Comparing this to patients with likely benign (LB) variants, the patients with likely-pathogenic (LP) variants have significantly more liver manifestations with elevated GGT (p = .0001). Significantly more patients with LP variants had extra-hepatic phenotypes of ALGS compared with those patients with LB variants (p = .0004). CONCLUSION: When NOTCH2 variants are absent in gnomAD, null variants and missense variants which were predicted to be pathogenic by at least three in-silico tools could be considered pathogenic in patients with high GGT chronic liver diseases.


Assuntos
Síndrome de Alagille , Receptor Notch2 , Síndrome de Alagille/diagnóstico , Síndrome de Alagille/genética , Humanos , Proteína Jagged-1/genética , Proteína Jagged-1/metabolismo , Mutação , Fenótipo , Receptor Notch2/genética , Receptor Notch2/metabolismo , Virulência
12.
Hum Mutat ; 41(2): 502-511, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31696999

RESUMO

To assess the spectrum of pediatric clinical phenotypes in TJP2 disease, we reviewed records of our seven patients in whom intrahepatic cholestasis was associated with biallelic TJP2 variants (13; 12 novel) and correlated clinical manifestations with mutation type. The effect of a splicing variant was analyzed with a minigene assay. The effects of three missense variants were analyzed with protein expression in vitro. Our patients had both remitting and persistent cholestasis. Three exhibited growth retardation. Six responded to treatment with cholestyramine, ursodeoxycholic acid, or both. Two had cholecystolithiasis. None required liver transplantation or developed hepatocellular or cholangiocellular malignancy. None manifested extrahepatic disease not attributable to effects of cholestasis. The variant c.2180-5T>G resulted in exon 15 skipping with in-frame deletion of 32 amino acid residues in TJP2. The three missense variants decreased but did not abolish TJP2 expression. Patients with truncating or canonical splice-site variants had clinically more severe disease. TJP2 disease in children includes a full clinical spectrum of severity, with mild or intermittent forms as well as the severe and minimal forms hitherto described. Biallelic TJP2 variants must be considered in children with clinically intermittent or resolved intrahepatic cholestasis.


Assuntos
Colestase Intra-Hepática/diagnóstico , Colestase Intra-Hepática/genética , Predisposição Genética para Doença , Variação Genética , Proteína da Zônula de Oclusão-2/genética , Idade de Início , Alelos , Substituição de Aminoácidos , Biópsia , Biologia Computacional/métodos , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Mutação , Linhagem , Splicing de RNA , Sequenciamento do Exoma
13.
J Fluoresc ; 30(3): 505-514, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32146649

RESUMO

A novel coumarin-thiourea conjugate was synthesized facilely. It served as a fluorescent turn-on chemosensor for selective detection of Hg2+ ion over other common competitive metal ions including Li+, Na+, K+, Ag+, Cu2+, Fe2+, Zn2+, Co2+, Ni2+, Mn2+, Sr2+, Ca2+, Mg2+, Al3+, Cr3+ and Fe3+ ions based on the Hg2+-promoted desulfurization and cyclization reactions. Addition of Hg2+ ion to the sensor solution in 2:8 EtOH/H2O induced a hypsochromic shift of the UV-Vis absorption band from 360 nm to 340 nm accompanying distinct enhancement in the absorption intensity while addition of other metal ions failed to bring about substantial change in the absorption spectra. Addition of Hg2+ to the sensor solution also caused marked increase in the fluorescence emission intensity and most common competitive metal ions did not interfere with the selective sensing of Hg2+ ion by the sensor. The detection limit of Hg2+ ion by the probe was calculated to be 1.46 × 10-7 M and the probe could be utilized for selective detection of Hg2+ ion by fluorescence turn-on mode over a broad pH range of 1-11.


Assuntos
Cumarínicos/química , Corantes Fluorescentes/química , Mercúrio/análise , Tioureia/química , Corantes Fluorescentes/síntese química , Concentração de Íons de Hidrogênio , Estrutura Molecular
14.
J Virol ; 92(11)2018 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-29593033

RESUMO

Group/species C rotaviruses (RVCs) have been identified as important pathogens of acute gastroenteritis (AGE) in children, family-based outbreaks, as well as animal infections. However, little is known regarding their host-specific interaction, infection, and pathogenesis. In this study, we performed serial studies to characterize the function and structural features of a human G4P[2] RVC VP8* that is responsible for the host receptor interaction. Glycan microarrays demonstrated that the human RVC VP8* recognizes type A histo-blood group antigens (HBGAs), which was confirmed by synthetic glycan-/saliva-based binding assays and hemagglutination of red blood cells, establishing a paradigm of RVC VP8*-glycan interactions. Furthermore, the high-resolution crystal structure of the human RVC VP8* was solved, showing a typical galectin-like structure consisting of two ß-sheets but with significant differences from cogent proteins of group A rotaviruses (RVAs). The VP8* in complex with a type A trisaccharide displays a novel ligand binding site that consists of a particular set of amino acid residues of the C-D, G-H, and K-L loops. RVC VP8* interacts with type A HBGAs through a unique mechanism compared with that used by RVAs. Our findings shed light on the host-virus interaction and the coevolution of RVCs and will facilitate the development of specific antivirals and vaccines.IMPORTANCE Group/species C rotaviruses (RVCs), members of Reoviridae family, infect both humans and animals, but our knowledge about the host factors that control host susceptibility and specificity is rudimentary. In this work, we characterized the glycan binding specificity and structural basis of a human RVC that recognizes type A HBGAs. We found that human RVC VP8*, the rotavirus host ligand binding domain that shares only ∼15% homology with the VP8* domains of RVAs, recognizes type A HBGA at an as-yet-unknown glycan binding site through a mechanism distinct from that used by RVAs. Our new advancements provide insights into RVC-cell attachment, the critical step of virus infection, which will in turn help the development of control and prevention strategies against RVs.


Assuntos
Antígenos de Grupos Sanguíneos/metabolismo , Oligossacarídeos/metabolismo , Proteínas de Ligação a RNA/metabolismo , Receptores Virais/metabolismo , Rotavirus/metabolismo , Proteínas não Estruturais Virais/metabolismo , Ligação Viral , Sistema ABO de Grupos Sanguíneos , Sequência de Aminoácidos , Animais , Sítios de Ligação/fisiologia , Proteínas do Capsídeo/metabolismo , Cristalografia por Raios X , Gastroenterite/patologia , Gastroenterite/virologia , Hemaglutinação/fisiologia , Especificidade de Hospedeiro , Interações Hospedeiro-Patógeno/fisiologia , Humanos , Oligossacarídeos de Cadeias Ramificadas , Infecções por Rotavirus/patologia , Infecções por Rotavirus/virologia , Alinhamento de Sequência
15.
Environ Sci Technol ; 53(9): 5337-5348, 2019 05 07.
Artigo em Inglês | MEDLINE | ID: mdl-30997803

RESUMO

To guide the design of novel graphene-based catalysts in catalytic ozonation for micropollutant degradation, the mechanism of catalytic ozonation with heteroatom-doped graphene was clarified. Reduced graphene oxide doped with nitrogen, phosphorus, boron, and sulfur atoms (N-, P-, B-, and S-rGO) were synthesized, and their catalytic ozonation performances were evaluated in the degradation of refractory organics and bromate elimination simultaneously. Doping with heteroatoms, except sulfur, significantly improved the catalytic ozonation activity of graphene. Introducing sulfur atoms destroyed the stability of graphene during ozonation, with the observed partial performance improvement caused by surface adsorption. Degradation pathways for selected refractory organics were proposed based on the intermediates identified using high-resolution Orbitrap mass spectroscopy and gas chromatographic-mass spectroscopy. Three and six new unopened intermediates were identified in benzotriazole and p-chlorobenzoic acid degradation, respectively. Roles of chemical functional groups, doped atoms, free electron, and delocalized π electron of heteroatom-doped graphene in catalytic ozonation were identified, and contributions of these active centers to the formation of reactive oxygen species (ROS), including hydroxyl radicals, superoxide radicals, singlet oxygen, and H2O2, were evaluated. A mechanism for catalytic ozonation by heteroatom-doped graphene was proposed for the first time.


Assuntos
Grafite , Ozônio , Catálise , Peróxido de Hidrogênio , Espécies Reativas de Oxigênio
16.
Sensors (Basel) ; 20(1)2019 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-31861804

RESUMO

Tea polyphenols are important ingredients for evaluating tea quality. The rapid development of sensors provides an efficient method for nondestructive detection of tea polyphenols. Previous studies have shown that features obtained from single or multiple sensors yield better results in detecting interior tea quality. However, due to their lack of external features, it is difficult to meet the general evaluation model for the quality of the interior and exterior of tea. In addition, some features do not fully reflect the sensor signals of tea for several categories. Therefore, a feature fusion method based on time and frequency domains from electronic nose (E-nose) and hyperspectral imagery (HSI) is proposed to estimate the polyphenol content of tea for cross-category evaluation. The random forest and the gradient boosting decision tree (GBDT) are used to evaluate the feature importance to obtain the optimized features. Three models based on different features for cross-category tea (black tea, green tea, and yellow tea) were compared, including grid support vector regression (Grid-SVR), random forest (RF), and extreme gradient boosting (XGBoost). The results show that the accuracy of fusion features based on the time and frequency domain from the electronic nose and hyperspectral image system is higher than that of the features from single sensor. Whether based on all original features or optimized features, the performance of XGBoost is the best among the three regression algorithms (R2 = 0.998, RMSE = 0.434). Results indicate that the proposed method in this study can improve the estimation accuracy of tea polyphenol content for cross-category evaluation, which provides a technical basis for predicting other components of tea.

17.
Sensors (Basel) ; 19(20)2019 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-31614815

RESUMO

Nitrogen (N) content is an important basis for the precise management of wheat fields. The application of unmanned aerial vehicles (UAVs) in agriculture provides an easier and faster way to monitor nitrogen content. Previous studies have shown that the features acquired from UAVs yield favorable results in monitoring wheat growth. However, since most of them are based on different vegetation indices, it is difficult to meet the requirements of accurate image interpretation. Moreover, resampling also easily ignores the structural features of the image information itself. Therefore, a spectral-spatial feature is proposed combining vegetation indices (VIs) and wavelet features (WFs), especially the acquisition of wavelet features from the UAV image, which was transformed from the spatial domain to the frequency domain with a wavelet transformation. In this way, the complete spatial information of different scales can be obtained to realize good frequency localization, scale transformation, and directional change. The different models based on different features were compared, including partial least squares regression (PLSR), support vector regression (SVR), and particle swarm optimization-SVR (PSO-SVR). The results showed that the accuracy of the model based on the spectral-spatial feature by combining VIs and WFs was higher than that of VIs or WF indices alone. The performance of PSO-SVR was the best (R2 = 0.9025, root mean square error (RMSE) = 0.3287) among the three regression algorithms regardless of the use of all the original features or the combination features. Our results implied that our proposed method could improve the estimation accuracy of aboveground nitrogen content of winter wheat from UAVs with consumer digital cameras, which have greater application potential in predicting other growth parameters.

18.
Virol J ; 15(1): 161, 2018 10 19.
Artigo em Inglês | MEDLINE | ID: mdl-30340611

RESUMO

BACKGROUND: Rotaviruses (RVs) are a major cause of acute children gastroenteritis. The rotavirus P [10] belongs to P[I] genogroup of group A rotaviruses that mainly infect animals, while the rotavirus P [10] was mainly identified from human infection. The rotavirus P [10] is an unusual genotype and the recognition pattern of cellular receptors remains unclear. METHODS: We expressed and purified the RV P [10] VP8* protein and investigated the saliva and oligosaccharide binding profiles of the protein. A homology model of the P [10] VP8* core protein was built and the superimposition structural analysis of P [10] VP8* protein on P [19] VP8* in complex with mucin core 2 was performed to explore the possible docking structural basis of P [10] VP8* and mucin cores. RESULTS: Our data showed that rotavirus P [10] VP8* protein bound to all ABO secretor and non-secretor saliva. The rotavirus P [10] could bind strongly to mucin core 2 and weakly to mucin core 4. The homology modeling indicated that RV P [10] VP8* binds to mucin core 2 using a potential glycan binding site that is the same to P [19] VP8* belonging to P[II] genogroup. CONCLUSION: Our results suggested an interaction of rotavirus P [10] VP8* protein with mucin core 2 and mucin core 4. These findings offer potential for elucidating the mechanism of RV A host specificity, evolution and epidemiology.


Assuntos
Polissacarídeos/química , Proteínas de Ligação a RNA/química , Infecções por Rotavirus/virologia , Rotavirus/genética , Proteínas não Estruturais Virais/química , Sítios de Ligação , Escherichia coli/genética , Gastroenterite/virologia , Humanos , Simulação de Acoplamento Molecular , Mucinas/química , Mucinas/metabolismo , Polissacarídeos/metabolismo , Ligação Proteica , Proteínas de Ligação a RNA/metabolismo , Saliva/química , Saliva/virologia , Análise de Sequência de Proteína , Proteínas não Estruturais Virais/metabolismo
19.
Biochim Biophys Acta Mol Basis Dis ; 1870(3): 167007, 2024 03.
Artigo em Inglês | MEDLINE | ID: mdl-38185063

RESUMO

The development of nonalcoholic fatty liver disease (NAFLD) may worsen due to chronic stress or prolonged use of glucocorticoids. Glycerol-3-phosphate acyltransferase 3 (GPAT3), has a function in obesity and serves as a key rate-limiting enzyme that regulates triglyceride synthesis. However, the precise impact of GPAT3 on corticosterone (CORT)-induced NAFLD and its underlying molecular mechanism remain unclear. For our in vivo experiments, we utilized male and female mice that were GPAT3-/- and wild type (WT) and treated them with CORT for a duration of 4 weeks. In our in vitro experiments, we transfected AML12 cells with GPAT3 siRNA and subsequently treated them with CORT. Under CORT-treated conditions, the absence of GPAT3 greatly improved obesity and hepatic steatosis while enhancing the expression of genes involved in fatty acid oxidation, as evidenced by our findings. In addition, the deletion of GPAT3 significantly inhibited the production of reactive oxygen species (ROS), increased the expression of antioxidant genes, and recovered the mitochondrial membrane potential in AML12 cells treated with CORT. In terms of mechanism, the absence of GPAT3 encouraged the activation of the glycogen synthase kinase 3ß (GSK3ß)/nuclear factor-erythroid 2 related factor 2 (Nrf2) pathway, which served as a defense mechanism against liver fat accumulation and oxidative stress. Furthermore, GPAT3 expression was directly controlled at the transcriptional level by the glucocorticoid receptor (GR). Collectively, our findings suggest that GPAT3 deletion significantly alleviated hepatic steatosis and oxidative stress through promoting GSK3ß/Nrf2 signaling pathways.


Assuntos
Hepatopatia Gordurosa não Alcoólica , Masculino , Feminino , Camundongos , Animais , Hepatopatia Gordurosa não Alcoólica/metabolismo , Corticosterona/farmacologia , Fator 2 Relacionado a NF-E2/genética , Fator 2 Relacionado a NF-E2/metabolismo , Glicogênio Sintase Quinase 3 beta/genética , Glicogênio Sintase Quinase 3 beta/metabolismo , Estresse Oxidativo , Obesidade/tratamento farmacológico , Obesidade/genética , Aciltransferases/metabolismo , 1-Acilglicerol-3-Fosfato O-Aciltransferase/genética , 1-Acilglicerol-3-Fosfato O-Aciltransferase/metabolismo
20.
J Cardiothorac Surg ; 19(1): 216, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38627737

RESUMO

During a routine physical examination three years ago, a 47-year-old woman received a diagnosis of a nodule in her right upper lung. Since then, she has been regularly attending outpatient clinic appointments for follow-up. Over time, the nodule has shown gradual growth, leading to a suspicion of lung cancer. Through the use of enhanced CT imaging, a three-dimensional reconstruction was performed to examine the bronchi and blood vessels in the patient's chest. This reconstruction revealed several variations in the anatomy of the anterior segment of the right upper lobe. Specifically, the anterior segmental bronchus (B3) was found to have originated from the right middle lung bronchus. Additionally, the medial subsegmental artery of the anterior segmental artery (A3b) and the medial segmental artery (A5) were observed to share a common trunk. As for the lateral subsegmental artery of the anterior segmental artery (A3a), it was found to have originated from the right inferior pulmonary trunk. Furthermore, the apical subsegmental artery of the apical segmental artery (A1a) and the posterior segmental artery (A2) were found to have a shared trunk.


Assuntos
Neoplasias Pulmonares , Pulmão , Humanos , Feminino , Pessoa de Meia-Idade , Pulmão/irrigação sanguínea , Artéria Pulmonar/diagnóstico por imagem , Artéria Pulmonar/anatomia & histologia , Brônquios/diagnóstico por imagem , Brônquios/anatomia & histologia , Neoplasias Pulmonares/diagnóstico por imagem , Neoplasias Pulmonares/cirurgia , Tórax
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