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1.
Plant Physiol ; 195(1): 395-409, 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38198215

RESUMO

Dwarfism is an important agronomic trait in fruit breeding programs. However, the germplasm resources required to generate dwarf pear (Pyrus spp.) varieties are limited. Moreover, the mechanisms underlying dwarfism remain unclear. In this study, "Yunnan" quince (Cydonia oblonga Mill.) had a dwarfing effect on "Zaosu" pear. Additionally, the dwarfism-related NAC transcription factor gene PbNAC71 was isolated from pear trees comprising "Zaosu" (scion) grafted onto "Yunnan" quince (rootstock). Transgenic Nicotiana benthamiana and pear OHF-333 (Pyrus communis) plants overexpressing PbNAC71 exhibited dwarfism, with a substantially smaller xylem and vessel area relative to the wild-type controls. Yeast one-hybrid, dual-luciferase, chromatin immunoprecipitation-qPCR, and electrophoretic mobility shift assays indicated that PbNAC71 downregulates PbWalls are thin 1 expression by binding to NAC-binding elements in its promoter. Yeast two-hybrid assays showed that PbNAC71 interacts with the E3 ubiquitin ligase PbRING finger protein 217 (PbRNF217). Furthermore, PbRNF217 promotes the ubiquitin-mediated degradation of PbNAC71 by the 26S proteasome, thereby regulating plant height as well as xylem and vessel development. Our findings reveal a mechanism underlying pear dwarfism and expand our understanding of the molecular basis of dwarfism in woody plants.


Assuntos
Regulação da Expressão Gênica de Plantas , Proteínas de Plantas , Plantas Geneticamente Modificadas , Pyrus , Fatores de Transcrição , Xilema , Xilema/metabolismo , Xilema/genética , Pyrus/genética , Pyrus/metabolismo , Pyrus/crescimento & desenvolvimento , Fatores de Transcrição/metabolismo , Fatores de Transcrição/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Nicotiana/genética , Nicotiana/metabolismo , Nicotiana/crescimento & desenvolvimento , Regiões Promotoras Genéticas/genética , Complexo de Endopeptidases do Proteassoma/metabolismo , Complexo de Endopeptidases do Proteassoma/genética
2.
J Cell Mol Med ; 28(2): e18066, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-38098223

RESUMO

The long noncoding RNA PVT1 is reported to act as an oncogene in several kinds of cancers, especially ovarian cancer (OV). Abnormal levels of N6 -methyladenosine, a dynamic and reversible modification, are associated with tumorigenesis and malignancies. Our previous study reported that PVT1 plays critical roles in regulating OV. However, it is still largely unknown how m6 A modification affects OV via PVT1. In this study, we aimed to investigate the regulation of ALKBH5 by affecting PVT1 in OV. We first found that the PVT1 RNA level was higher in OV cells than in IOSE80 cells, and conversely, the m6 A modification level of PVT1 was lower in OV cells. By searching the HPA, ALKBH5, which is responsible for PVT1 demethylation, was found to be upregulated in OV tissues versus normal ovarian tissues. ALKBH5 binds to PVT1 RNA, and knockdown of ALKBH5 decreased PVT1 RNA levels. ALKBH5 also increased FOXM1 levels by upregulating PVT1, at least partially. Knockdown of ALKBH5 suppressed OV growth, colony formation, tumour formation and invasion, which were partially reversed by overexpression of PVT1. Moreover, ALKBH5 knockdown decreased FOXM1 levels by regulating PVT1 RNA expression, subsequently increasing the sensitivity to carboplatin, 5-FU and docetaxel chemotherapy. Taken together, these results indicate that ALKBH5 directly regulates the m6 A modification and stability of PVT1. Then, modified PVT1 further regulates FOXM1 and thus affects malignant behaviours and chemosensitivity in OV cells. All these results indicate that ALKBH5 regulates the malignant behaviour of OV by regulating PVT1/FOXM1.


Assuntos
Neoplasias Ovarianas , RNA Longo não Codificante , Humanos , Feminino , RNA Longo não Codificante/metabolismo , Proliferação de Células/genética , Neoplasias Ovarianas/patologia , Docetaxel , Carboplatina , Homólogo AlkB 5 da RNA Desmetilase/genética , Homólogo AlkB 5 da RNA Desmetilase/metabolismo
3.
Eur J Neurosci ; 2024 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-38992988

RESUMO

The involvement of inwardly rectifying potassium channel 4.1 (Kir4.1) in neuropathic pain has been established. However, there is limited understanding of the downstream mechanism through which Kir4.1 contributes to orofacial neuropathic pain. The objective of this study was to examine the regulation of Kir4.1 on the expression of pannexin 3 (Panx3) in the trigeminal ganglion (TG) and the underlying mechanism in the context of orofacial neuropathic pain caused by chronic constriction injury of the infraorbital nerve (CCI-ION). The study observed a significant increase in Panx3 expression in the TG of mice with CCI-ION. Inhibition of Panx3 in the TG of CCI-ION mice resulted in alleviation of orofacial mechanical allodynia. Furthermore, conditional knockdown (CKD) of Kir4.1 in the TG of both male and female mice led to mechanical allodynia and upregulation of Panx3 expression. Conversely, overexpression of Kir4.1 decreased Panx3 levels in the TG and relieved mechanical allodynia in CCI-ION mice. In addition, silencing Kir4.1 in satellite glial cells (SGCs) decreased Panx3 expression and increased the phosphorylation of P38 MAPK. Moreover, silencing Kir4.1 in SGCs increased the levels of reactive oxygen species (ROS). The elevated phosphorylation of P38 MAPK resulting from Kir4.1 silencing was inhibited by using a superoxide scavenger known as the tempol. Silencing Panx3 in the TG in vivo attenuated the mechanical allodynia caused by Kir4.1 CKD. In conclusion, these findings suggest that the reduction of Kir4.1 promotes the expression of Panx3 by activating the ROS-P38 MAPK signalling pathway, thus contributing to the development of orofacial neuropathic pain.

4.
Anal Chem ; 96(24): 10013-10020, 2024 06 18.
Artigo em Inglês | MEDLINE | ID: mdl-38836548

RESUMO

Traditional methods for the detection of pathogenic bacteria are time-consuming, less efficient, and sensitive, which affects infection control and bungles illness. Therefore, developing a method to remedy these problems is very important in the clinic to diagnose the pathogenic diseases and guide the rational use of antibiotics. Here, microfluidic electrochemical integrated sensor (MEIS) has been investigated, functionally for rapid, efficient separation and sensitive detection of pathogenic bacteria. Three-dimensional macroporous PDMS and Au nanotube-based electrode are successfully assembled into the modeling microchip, playing the functions of "3D chaotic flow separator" and "electrochemical detector," respectively. The 3D chaotic flow separator enhances the turbulence of the fluid, achieving an excellent bacteria capture efficiency. Meanwhile, the electrochemical detector provides a quantitative signal through enzyme-linked immunoelectrochemistry with improved sensitivity. The microfluidic electrochemical integrated sensor could successfully isolate Candida albicans (C. albicans) in the range of 30-3,000,000 CFU in the saliva matrix with over 95% capture efficiency and sensitively detect C. albicans in 1 h in oral saliva samples. The integrated device demonstrates great potential in the diagnosis of oral candidiasis and is also applicable in the detection of other pathogenic bacteria.


Assuntos
Candida albicans , Técnicas Eletroquímicas , Candida albicans/isolamento & purificação , Técnicas Eletroquímicas/instrumentação , Técnicas Analíticas Microfluídicas/instrumentação , Saliva/microbiologia , Saliva/química , Eletrodos , Humanos , Ouro/química
5.
BMC Plant Biol ; 24(1): 617, 2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-38937686

RESUMO

BACKGROUND: Ichang papeda (Citrus ichangensis), a wild perennial plant of the Rutaceae family, is a cold-hardy plant. WRKY transcription factors are crucial regulators of plant growth and development as well as abiotic stress responses. However, the WRKY genes in C. ichangensis (CiWRKY) and their expression patterns under cold stress have not been thoroughly investigated, hindering our understanding of their role in cold tolerance. RESULTS: In this study, a total of 52 CiWRKY genes identified in the genome of C. ichangensis were classified into three main groups and five subgroups based on phylogenetic analysis. Comprehensive analyses of motif features, conserved domains, and gene structures were performed. Segmental duplication plays a significant role in the CiWRKY gene family expansion. Cis-acting element analysis revealed the presence of various stress-responsive elements in the promoters of the majority of CiWRKYs. Gene ontology (GO) analysis and protein-protein interaction predictions indicate that the CiWRKYs exhibit crucial roles in regulation of both development and stress response. Expression profiling analysis demonstrates that 14 CiWRKYs were substantially induced under cold stress. Virus-induced gene silencing (VIGS) assay confirmed that CiWRKY31, one of the cold-induced WRKYs, functions positively in regulation of cold tolerance. CONCLUSION: Sequence and protein properties of CiWRKYs were systematically analyzed. Among the 52 CiWRKY genes 14 members exhibited cold-responsive expression patterns, and CiWRKY31 was verified to be a positive regulator of cold tolerance. These findings pave way for future investigations to understand the molecular functions of CiWRKYs in cold tolerance and contribute to unravelling WRKYs that may be used for engineering cold tolerance in citrus.


Assuntos
Citrus , Resposta ao Choque Frio , Regulação da Expressão Gênica de Plantas , Filogenia , Proteínas de Plantas , Fatores de Transcrição , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Citrus/genética , Citrus/fisiologia , Resposta ao Choque Frio/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Genoma de Planta , Perfilação da Expressão Gênica , Genes de Plantas , Temperatura Baixa
6.
Artigo em Inglês | MEDLINE | ID: mdl-38752995

RESUMO

A novel actinobacterium, strain ZYX-F-186T, was isolated from marine sediment sampled on Yongxing Island, Hainan Province, PR China. Based on the results of 16S rRNA gene sequence analysis, strain ZYX-F-186T belongs to the genus Phytohabitans, with high similarity to Phytohabitans kaempferiae KK1-3T (98.3 %), Phytohabitans rumicis K11-0047T (98.1 %), Phytohabitans flavus K09-0627T (98.1 %), Phytohabitans houttuyneae K11-0057T (97.9 %), Phytohabitans suffuscus K07-0523T (97.7 %), and Phytohabitans aurantiacus RD004123T (97.7 %). Phylogenetic analysis of 16S rRNA gene sequences showed that the strain formed a single subclade in the genus Phytohabitans. The novel isolate contained meso-diaminopimelic acid, d-glutamic acid, glycine, d-alanine, and l-lysine in the cell wall. The whole-cell sugars were xylose, arabinose, ribose, and rhamnose. The predominant menaquinones were MK-9(H8), MK-9(H6), and MK-9(H4). The characteristic phospholipids were phosphatidylethanolamine, phosphatidylinositol, phosphatidylmethylethanolamine, phosphatidylglycerol, and an unknown phospholipid. The major fatty acids (>5 %) were iso-C16 : 0, anteiso-C17 : 0, and iso-C18 : 0. Genome sequencing showed a DNA G+C content of 71.9 mol%. Low average nucleotide identity, digital DNA-DNA hybridization, and average amino acid identity values demonstrated that strain ZYX-F-186T could be readily distinguished from its closely related species. Based on its phylogenetic, chemotaxonomic, and physiological characteristics, strain ZYX-F-186T represents a novel species of the genus Phytohabitans, for which the name Phytohabitans maris sp. nov. is proposed. The type strain is ZYX-F-186T (=CGMCC 4.8025T=CCTCC AA 2023025T=JCM 36507T).


Assuntos
Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano , Ácidos Graxos , Sedimentos Geológicos , Filogenia , RNA Ribossômico 16S , Análise de Sequência de DNA , Sedimentos Geológicos/microbiologia , RNA Ribossômico 16S/genética , China , DNA Bacteriano/genética , Ácidos Graxos/química , Fosfolipídeos , Vitamina K 2/análogos & derivados , Vitamina K 2/análise , Vitamina K 2/química , Hibridização de Ácido Nucleico , Parede Celular/química
7.
Acta Pharmacol Sin ; 45(5): 1002-1018, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38225395

RESUMO

Diabetes mellitus results in numerous complications. Diabetic pulmonary fibrosis (DPF), a late pulmonary complication of diabetes, has not attracted as much attention as diabetic nephropathy and cardiomyopathy. Mangiferin (MF) is a natural small molecular compound that exhibits a variety of pharmacological effects including anti-inflammatory, anti-cancer, anti-diabetes, and anti-fibrosis effects. In this study, we investigated whether long-term diabetes shock induces DPF, and explored whether MF had a protective effect against DPF. We first examined the lung tissues and sections of 20 diabetic patients obtained from discarded lung surgical resection specimens and found that pulmonary fibrosis mainly accumulated around the pulmonary vessels, accompanied by significantly enhanced endothelial-mesenchymal transition (EndMT). We established a mouse model of DPF by STZ injections. Ten days after the final STZ injection, the mice were administered MF (20, 60 mg/kg, i.g.) every 3 days for 4 weeks, and kept feeding until 16 weeks and euthanized. We showed that pulmonary fibrotic lesions were developed in the diabetic mice, which began around the pulmonary vessels, while MF administration did not affect long-term blood glucose levels, but dose-dependently alleviated diabetes-induced pulmonary fibrosis. In human umbilical vein endothelial cells (HUVECs), exposure to high glucose (33.3 mM) induced EndMT, which was dose-dependently inhibited by treatment with MF (10, 50 µM). Furthermore, MF treatment promoted SIRT3 expression in high glucose-exposed HUVECs by directly binding to AMPK to enhance the activity of FoxO3, which finally reversed diabetes-induced EndMT. We conclude that MF attenuates DPF by inhibiting EndMT through the AMPK/FoxO3/SIRT3 axis. MF could be a potential candidate for the early prevention and treatment of DPF.


Assuntos
Proteínas Quinases Ativadas por AMP , Diabetes Mellitus Experimental , Proteína Forkhead Box O3 , Camundongos Endogâmicos C57BL , Fibrose Pulmonar , Sirtuína 3 , Xantonas , Animais , Xantonas/farmacologia , Xantonas/uso terapêutico , Fibrose Pulmonar/tratamento farmacológico , Fibrose Pulmonar/metabolismo , Sirtuína 3/metabolismo , Diabetes Mellitus Experimental/tratamento farmacológico , Diabetes Mellitus Experimental/complicações , Diabetes Mellitus Experimental/metabolismo , Proteína Forkhead Box O3/metabolismo , Masculino , Humanos , Camundongos , Proteínas Quinases Ativadas por AMP/metabolismo , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Estreptozocina , Transdução de Sinais/efeitos dos fármacos , Transição Endotélio-Mesênquima
8.
BMC Pregnancy Childbirth ; 24(1): 347, 2024 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-38711000

RESUMO

BACKGROUND: This study investigates the causal relationship between lipid traits and GDM in an effort to better understand the aetiology of GDM. METHODS: Employing a two-sample Mendelian Randomization (MR) framework, we used Single Nucleotide Polymorphisms (SNPs) as instrumental variables to examine the impact of lipids and apolipoproteins on GDM. The research comprised univariable and multivariable MR analyses, with a prime focus on individual and combined effects of lipid-related traits. Statistical techniques included the fixed-effect inverse variance weighted (IVW) method and supplementary methods such as MR-Egger for comprehensive assessment. RESULTS: Our findings revealed the following significant associations: apoA-I and HDL cholesterol were inversely correlated with GDM risk, while triglycerides showed a positive correlation. In multivariable analysis, apoA-I consistently exhibited a strong causal link with GDM, even after adjusting for other lipids and Body Mass Index (BMI). CONCLUSION: The study demonstrates a significant causal relationship between apoA-I and GDM risk.


Assuntos
Apolipoproteína A-I , HDL-Colesterol , Diabetes Gestacional , Análise da Randomização Mendeliana , Polimorfismo de Nucleotídeo Único , Triglicerídeos , Humanos , Feminino , Gravidez , Diabetes Gestacional/genética , Diabetes Gestacional/sangue , Triglicerídeos/sangue , Apolipoproteína A-I/sangue , Apolipoproteína A-I/genética , HDL-Colesterol/sangue , Apolipoproteínas/sangue , Apolipoproteínas/genética , Índice de Massa Corporal , Lipídeos/sangue , Fatores de Risco
9.
Zhongguo Zhong Yao Za Zhi ; 49(3): 717-727, 2024 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-38621875

RESUMO

Transcriptome sequencing was employed to mine the simple sequence repeat(SSR) locus information of Saposhnikovia divaricata and design specific primers, which aimed to provide a basis for the research on the genetic diversity of S. divaricata germplasm resources. The seed purity, 1 000-seed weight, germination rate, and seed vigor were determined. MISA was used to obtain the SSR locus information from 12 606 unigene longer than 1 kb in the transcriptome database. Forty-three pairs of SSR primers designed in Primer 3 were used to analyze the polymorphism of 28 S. divaricata samples of different sources. The results showed that there were differences in the seed purity, 1 000-seed weight, germination rate, vigor, and seed length and width among S. divaricata samples of different sources. Particularly, the germination rate and seed vigor had significant differences, and HB-ZJK1, NMG-CF4, NMG-BT, NMG-HLE1, and NMG-CF2 had significantly higher 1 000-seed weight, germination rate, and seed vigor than the samples of other sources. Among the 86 233 unigene, 12 606(14.62%) unigene contained 15 958 SSR loci, with one SSR locus every 5 009 bp on average. The SSR loci were mainly single nucleotide and dinucleotide repeats, which were dominated by G/C and TC/AG, respectively. All the primers were screened by using 28 S. divaricata sample from different habitats, and the primers corresponding to the amplification products with clear bands and stable polymorphism were obtained. The clustering results of the biological characteristics and genetic diversity of the 28 S. divaricata samples were basically consistent, and the samples of the same origin(HB-AG1, HB-AG2, HB-ZJK1, and HB-ZJK2) generally gathered together and had close genetic relationship. The SSRs in S. divaricata transcriptome has high frequency, rich types, and high polymorphism, which provides candidate molecular markers for the germplasm identification, genetic map construction, and molecular-assisted breeding.


Assuntos
Apiaceae , Transcriptoma , Polimorfismo Genético , Repetições de Microssatélites/genética , Apiaceae/genética , Etiquetas de Sequências Expressas
10.
Thorax ; 78(4): 335-343, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36598042

RESUMO

RATIONALE: Severe asthma and chronic obstructive pulmonary disease (COPD) share common pathophysiological traits such as relative corticosteroid insensitivity. We recently published three transcriptome-associated clusters (TACs) using hierarchical analysis of the sputum transcriptome in asthmatics from the Unbiased Biomarkers for the Prediction of Respiratory Disease Outcomes (U-BIOPRED) cohort comprising one Th2-high inflammatory signature (TAC1) and two Th2-low signatures (TAC2 and TAC3). OBJECTIVE: We examined whether gene expression signatures obtained in asthma can be used to identify the subgroup of patients with COPD with steroid sensitivity. METHODS: Using gene set variation analysis, we examined the distribution and enrichment scores (ES) of the 3 TACs in the transcriptome of bronchial biopsies from 46 patients who participated in the Groningen Leiden Universities Corticosteroids in Obstructive Lung Disease COPD study that received 30 months of treatment with inhaled corticosteroids (ICS) with and without an added long-acting ß-agonist (LABA). The identified signatures were then associated with longitudinal clinical variables after treatment. Differential gene expression and cellular convolution were used to define key regulated genes and cell types. MEASUREMENTS AND MAIN RESULTS: Bronchial biopsies in patients with COPD at baseline showed a wide range of expression of the 3 TAC signatures. After ICS±LABA treatment, the ES of TAC1 was significantly reduced at 30 months, but those of TAC2 and TAC3 were unaffected. A corticosteroid-sensitive TAC1 signature was developed from the TAC1 ICS-responsive genes. This signature consisted of mast cell-specific genes identified by single-cell RNA-sequencing and positively correlated with bronchial biopsy mast cell numbers following ICS±LABA. Baseline levels of gene transcription correlated with the change in RV/TLC %predicted following 30-month ICS±LABA. CONCLUSION: Sputum-derived transcriptomic signatures from an asthma cohort can be recapitulated in bronchial biopsies of patients with COPD and identified a signature of airway mast cells as a predictor of corticosteroid responsiveness.


Assuntos
Corticosteroides , Asma , Mastócitos , Doença Pulmonar Obstrutiva Crônica , Células Th2 , Humanos , Administração por Inalação , Corticosteroides/uso terapêutico , Agonistas de Receptores Adrenérgicos beta 2/uso terapêutico , Asma/tratamento farmacológico , Asma/genética , Biomarcadores , Broncodilatadores/uso terapêutico , Quimioterapia Combinada , Mastócitos/efeitos dos fármacos , Mastócitos/metabolismo , Doença Pulmonar Obstrutiva Crônica/tratamento farmacológico , Doença Pulmonar Obstrutiva Crônica/genética , Células Th2/efeitos dos fármacos , Células Th2/metabolismo
11.
Thorax ; 78(7): 661-673, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36344253

RESUMO

BACKGROUND: Severe neutrophilic asthma is resistant to treatment with glucocorticoids. The immunomodulatory protein macrophage migration inhibitory factor (MIF) promotes neutrophil recruitment to the lung and antagonises responses to glucocorticoids. We hypothesised that MIF promotes glucocorticoid resistance of neutrophilic inflammation in severe asthma. METHODS: We examined whether sputum MIF protein correlated with clinical and molecular characteristics of severe neutrophilic asthma in the Unbiased Biomarkers for the Prediction of Respiratory Disease Outcomes (U-BIOPRED) cohort. We also investigated whether MIF regulates neutrophilic inflammation and glucocorticoid responsiveness in a murine model of severe asthma in vivo. RESULTS: MIF protein levels positively correlated with the number of exacerbations in the previous year, sputum neutrophils and oral corticosteroid use across all U-BIOPRED subjects. Further analysis of MIF protein expression according to U-BIOPRED-defined transcriptomic-associated clusters (TACs) revealed increased MIF protein and a corresponding decrease in annexin-A1 protein in TAC2, which is most closely associated with airway neutrophilia and NLRP3 inflammasome activation. In a murine model of severe asthma, treatment with the MIF antagonist ISO-1 significantly inhibited neutrophilic inflammation and increased glucocorticoid responsiveness. Coimmunoprecipitation studies using lung tissue lysates demonstrated that MIF directly interacts with and cleaves annexin-A1, potentially reducing its biological activity. CONCLUSION: Our data suggest that MIF promotes glucocorticoid-resistance of neutrophilic inflammation by reducing the biological activity of annexin-A1, a potent glucocorticoid-regulated protein that inhibits neutrophil accumulation at sites of inflammation. This represents a previously unrecognised role for MIF in the regulation of inflammation and points to MIF as a potential therapeutic target for the management of severe neutrophilic asthma.


Assuntos
Asma , Fatores Inibidores da Migração de Macrófagos , Humanos , Animais , Camundongos , Fatores Inibidores da Migração de Macrófagos/metabolismo , Fatores Inibidores da Migração de Macrófagos/uso terapêutico , Glucocorticoides/farmacologia , Glucocorticoides/uso terapêutico , Modelos Animais de Doenças , Asma/tratamento farmacológico , Asma/metabolismo , Inflamação/metabolismo , Neutrófilos/metabolismo , Anexinas/metabolismo , Anexinas/uso terapêutico
12.
Small ; 19(25): e2300289, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36929092

RESUMO

Dual single atoms catalysts have promising application in bifunctional electrocatalysis due to their synergistic effect. However, how to balance the competition between rate-limiting steps (RDSs) of reversible oxygen reduction and oxygen evolution reaction (OER) and fully expose the active centers by reasonable structure design remain enormous challenges. Herein, Fe/N4 and Ni/N4 sites separated on different sides of the carbon nanosheets with Janus structure (FeNijns /NC) is synthesized by layer-by-layer assembly method. Experiments and calculations reveal that the side of Fe/N4 is beneficial to oxygen reduction reaction (ORR) and the Ni/N4 side is preferred to OER. Such Janus structure can take full advantage of two separate-sides of carbon nanosheets and balance the competition of RDSs during ORR and OER. FeNijns /NC possesses superior ORR and OER activity with ORR half-wave potential of 0.92 V and OER overpotential of 440 mV at J = 10 mA cm-2 . Benefiting from the excellent bifunctional activities, FeNijns /NC assembled aqueous Zn-air battery (ZAB) demonstrates better maximum power density, and long-term stability (140 h) than Pt/C+RuO2 catalyst. It also reveals superior flexibility and stability in solid-state ZAB. This work brings a novel perspective for rational design and understanding of the catalytic mechanisms of dual single atom catalysts.

13.
J Neurosci Res ; 101(7): 1170-1187, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-36807930

RESUMO

Inward-rectifying K+ channel 4.1 (Kir4.1), which regulates the electrophysiological properties of neurons and glia by affecting K+ homeostasis, plays a critical role in neuropathic pain. Metabotropic glutamate receptor 5 (mGluR5) regulates the expression of Kir4.1 in retinal Müller cells. However, the role of Kir4.1 and its expressional regulatory mechanisms underlying orofacial ectopic allodynia remain unclear. This study aimed to investigate the biological roles of Kir4.1 and mGluR5 in the trigeminal ganglion (TG) in orofacial ectopic mechanical allodynia and the role of mGluR5 in Kir4.1 regulation. An animal model of nerve injury was established via inferior alveolar nerve transection (IANX) in male C57BL/6J mice. Behavioral tests indicated that mechanical allodynia in the ipsilateral whisker pad lasted at least 14 days after IANX surgery and was alleviated by the overexpression of Kir4.1 in the TG, as well as intraganglionic injection of an mGluR5 antagonist (MPEP hydrochloride) or a protein kinase C (PKC) inhibitor (chelerythrine chloride); Conditional knockdown of the Kir4.1 gene downregulated mechanical thresholds in the whisker pad. Double immunostaining revealed that Kir4.1 and mGluR5 were co-expressed in satellite glial cells in the TG. IANX downregulated Kir4.1 and upregulated mGluR5 and phosphorylated PKC (p-PKC) in the TG; Inhibition of mGluR5 reversed the changes in Kir4.1 and p-PKC that were induced by IANX; Inhibition of PKC activation reversed the downregulation of Kir4.1 expression caused by IANX (p < .05). In conclusion, activation of mGluR5 in the TG after IANX contributed to orofacial ectopic mechanical allodynia by suppressing Kir4.1 via the PKC signaling pathway.


Assuntos
Hiperalgesia , Receptor de Glutamato Metabotrópico 5 , Ratos , Camundongos , Masculino , Animais , Hiperalgesia/etiologia , Ratos Sprague-Dawley , Camundongos Endogâmicos C57BL , Nervo Mandibular/metabolismo , Nervo Mandibular/cirurgia
14.
Chembiochem ; 24(23): e202300582, 2023 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-37728423

RESUMO

(R)-ß-piperonyl-γ-butyrolactones are key building blocks for the synthesis of podophyllotoxin, which have demonstrated remarkable potential in cancer treatment. Baeyer-Villiger monooxygenases (BVMOs)-mediated asymmetric oxidation is a green approach to produce chiral lactones. While several BVMOs were able to oxidize the corresponding cyclobutanone, most BVMOs gave the (S) enantiomer while Cyclohexanone monooxygenase (CHMO) from Brevibacterium sp. HCU1 gave (R) enantiomer, but with a low enantioselectivity (75 % ee). In this study, we use a strategy called "focused rational iterative site-specific mutagenesis" (FRISM) at residues ranging from 6 Šfrom substrate. The mutations by using a restricted set of rationally chosen amino acids allow the formation of a small mutant library. By generating and screening less than 60 variants, we achieved a high ee of 96.8 %. Coupled with the cofactor regeneration system, 9.3 mM substrate was converted completely in a 100-mL scale reaction. Therefore, our work reveals a promising synthetic method for (R)-ß-piperonyl-γ-butyrolactone with the highest enantioselectivity, and provides a new opportunity for the chem-enzymatic synthesis of podophyllotoxin.


Assuntos
Oxigenases , Podofilotoxina , Oxigenases/metabolismo , Oxigenases de Função Mista/metabolismo , Oxirredução , Especificidade por Substrato
15.
Rev Cardiovasc Med ; 24(12): 356, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-39077082

RESUMO

Background: The prognosis of patients with acute coronary syndrome (ACS) varies greatly, and risk assessment models can help clinicians to identify and manage high-risk patients. While the Global Registry of Acute Coronary Events (GRACE) model is widely used, the clinical pathways for acute coronary syndromes (CPACS), which was constructed based on the Chinese population, and acute coronary treatment and intervention outcomes network (ACTION) have not yet been validated in the Chinese population. Methods: Patients with ACS who underwent coronary angiography or percutaneous coronary intervention from 2011 to 2020, were retrospectively recruited and the appropriate corresponding clinical indicators was obtained. The primary endpoint was in-hospital mortality. The performance of the GRACE, GRACE 2.0, ACTION, thrombolysis in myocardial infarction (TIMI) and CPACS risk models was evaluated and compared. Results: A total of 19,237 patients with ACS were included. Overall, in-hospital mortality was 2.2%. ACTION showed the highest accuracy in predicting discriminated risk (c-index 0.945, 95% confidence interval [CI] 0.922-0.955), but the calibration was not satisfactory. GRACE and GRACE 2.0 did not significantly differ in discrimination (p = 0.1480). GRACE showed the most accurate calibration in all patients and in the subgroup analysis of all models. CPACS (c-index 0.841, 95% CI 0.821-0.861) and TIMI (c-index 0.811, 95% CI 0.787-0.835) did not outperform (c-index 0.926, 95% CI 0.911-0.940). Conclusions: In contemporary Chinese ACS patients, the ACTION risk model's calibration is not satisfactory, although outperformed the gold standard GRACE model in predicting hospital mortality. The CPACS model developed for Chinese patients did not show better predictive performance than the GRACE model.

16.
Opt Lett ; 48(11): 3063-3066, 2023 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-37262281

RESUMO

Rotated optical axis waveguides can facilitate on-chip arbitrary wave-plate operations, which are crucial tools for developing integrated universal quantum computing algorithms. In this paper, we propose a unique technique based on femtosecond laser direct writing technology to fabricate arbitrarily rotated optical axis waveguides. First, a circular isotropic main waveguide with a non-optical axis was fabricated using a beam shaping method. Thereafter, a trimming line was used to create an artificial stress field near the main waveguide to induce a rotated optical axis. Using this technique, we fabricated high-performance half- and quarter-wave plates. Subsequently, high-fidelity (97.1%) Pauli-X gate operation was demonstrated via quantum process tomography, which constitutes the basis for the full manipulation of on-chip polarization-encoded qubits. In the future, this work is expected to lead to new prospects for polarization-encoded information in photonic integrated circuits.

17.
Cell Commun Signal ; 21(1): 17, 2023 01 23.
Artigo em Inglês | MEDLINE | ID: mdl-36691021

RESUMO

BACKGROUND: The inflammatory response induced by intestinal ischaemia‒reperfusion injury (I/R) is closely associated with infectious complications and mortality in critically ill patients, and the timely and effective clearance of apoptotic cells is an important part of reducing the inflammatory response. Studies have shown that the efferocytosis by phagocytes plays an important role. Recently, studies using small intestine organoid models showed that macrophage efferocytosis could promote the repair capacity of the intestinal epithelium. However, no studies have reported efferocytosis in the repair of I/R in animal models. RESULTS: We used an in vivo efferocytosis assay and discovered that macrophage efferocytosis played an indispensable role in repairing and maintaining intestinal barrier function after I/R. In addition, the specific molecular mechanism that induced macrophage efferocytosis was Cth-ERK1/2 dependent. We found that Cth drove macrophage efferocytosis in vivo and in vitro. Overexpression/silencing Cth promoted/inhibited the ERK1/2 pathway, respectively, which in turn affected efferocytosis and mediated intestinal barrier recovery. In addition, we found that the levels of Cth and macrophage efferocytosis were positively correlated with the recovery of intestinal function in clinical patients. CONCLUSION: Cth can activate the ERK1/2 signalling pathway, induce macrophage efferocytosis, and thus promote intestinal barrier repair. Video Abstract.


Assuntos
Cistationina gama-Liase , Intestinos , Sistema de Sinalização das MAP Quinases , Macrófagos , Animais , Cistationina gama-Liase/metabolismo , Macrófagos/metabolismo , Fagocitose , Transdução de Sinais , Humanos , Camundongos , Intestinos/lesões , Intestinos/fisiologia
18.
Biomacromolecules ; 24(4): 1662-1674, 2023 04 10.
Artigo em Inglês | MEDLINE | ID: mdl-36913719

RESUMO

Numerous metabolic reactions and pathways use adenosine 5'-triphosphate (ATP) as an energy source and as a phosphorous or pyrophosphorous donor. Based on three-dimensional (3D)-printing, enzyme immobilization can be used to improve ATP regeneration and operability and reduce cost. However, due to the relatively large mesh size of 3D-bioprinted hydrogels soaked in a reaction solution, the lower-molecular-weight enzymes cannot avoid leaking out of the hydrogels readily. Here, a chimeric adenylate-kinase-spidroin (ADK-RC) is created, with ADK serving as the N-terminal domain. The chimera is capable of self-assembling to form micellar nanoparticles at a higher molecular scale. Although fused to spidroin (RC), ADK-RC remains relatively consistent and exhibits high activity, thermostability, pH stability, and organic solvent tolerance. Considering different surface-to-volume ratios, three shapes of enzyme hydrogels are designed, 3D bioprinted, and measured. In addition, a continuous enzymatic reaction demonstrates that ADK-RC hydrogels have higher specific activity and substrate affinity but a lower reaction rate and catalytic power compared to free enzymes in solution. With ATP regeneration, the ADK and ADK-RC hydrogels significantly increase the production of d-glucose-6-phosphate and obtain an efficient usage frequency. In conclusion, enzymes fused to spidroin might be an efficient strategy for maintaining activity and reducing leakage in 3D-bioprinted hydrogels under mild conditions.


Assuntos
Adenilato Quinase , Fibroínas , Adenilato Quinase/química , Adenilato Quinase/metabolismo , Hidrogéis , Trifosfato de Adenosina/química , Catálise
19.
Artigo em Inglês | MEDLINE | ID: mdl-37252855

RESUMO

A novel actinobacterium strain (M4I6T) was isolated from marine sediment collected in Megas Gialos, Syros, Greece. On the basis of 16S rRNA gene sequence analysis, strain M4I6T was indicated as belonging to the genus Actinoplanes, with high similarity to 'Actinoplanes solisilvae' LAM7112T (97.9 %), Actinoplanes ferrugineus IFO 15555T (97.6 %), Actinoplanes cibodasensis LIPI11-2-Ac042T (97.2 %) and Actinoplanes bogorensis LIPI11-2-Ac043T (97.2 %). Phylogenetic analysis of the 16S rRNA gene sequence of strain M4I6T showed that the strain formed a stable subclade with 'A. solisilvae' LAM7112T. The cell wall of the novel isolate contained meso-diaminopimelic acid and the whole-cell sugars were xylose, glucose and ribose. The predominant menaquinones were MK-9(H4), MK-9(H2) and MK-9(H8). The phospholipid profile comprised phosphatidylethanolamine, phosphatidylinositol, diphosphatidylglycerol, phosphatidylglycerol, phosphatidylinositol mannosides and an unknown phospholipid. The major fatty acids (>5 %) were anteiso-C16 : 0, iso-C17 : 0, 10-methyl-C16 : 0, C15 : 0, iso-C16 : 0 and C17 : 0. Genome sequencing showed a DNA G+C content of 70.9 mol%. However, the low average nucleotide identity value, digital DNA-DNA hybridization and average amino acid identity values demonstrated that strain M4I6T could be readily distinguished from its closest related species. Based on data from this polyphasic study, strain M4I6T represents a novel species of the genus Actinoplanes, for which the name Actinoplanes maris sp. nov. is proposed. The type strain is M4I6T (=DSM 101017T=CGMCC 4.7854T).


Assuntos
Actinoplanes , Micromonosporaceae , Ácidos Graxos/química , Filogenia , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Composição de Bases , Técnicas de Tipagem Bacteriana , DNA Bacteriano/genética , Fosfolipídeos/química , Fosfatidilinositóis , Sedimentos Geológicos , Vitamina K 2/química
20.
Curr Allergy Asthma Rep ; 23(2): 111-119, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36574210

RESUMO

PURPOSE OF REVIEW: A number of sequelae after acute coronavirus disease 2019 (COVID-19) significantly affect the quality of life of patients. The chemosensory disorders including olfactory dysfunction (OD) and gustatory dysfunction (GD) are two of the commonest symptoms complained by patients with COVID-19. Although chemosensory function has been reported improved in over 60% of COVID-19 patients in a short time after acute infection, it may last as a major symptom for patients with long COVID-19. This narrative review discussed current literatures on OD and GD in long COVID-19 including the prevalence, risk factors, possible mechanisms, and potential therapies. RECENT FINDINGS: Although the prevalence of OD and GD has declined continuously after acute COVID-19, a considerable number of patients had persistent chemosensory disorders 3 months to 2 years after symptom onset. Female gender, initial severity of dysfunction, nasal congestion, emotional distress and depression, and SARS-CoV-2 variants have been identified as risk factors for persistent OD and GD in long COVID-19. The pathogenesis of OD and GD in long COVID-19 remains unknown, but may be analogous to the persistent OD and GD post common respiratory viral infection. Corticosteroids and olfactory training might be a potential choice regarding the treatment of lasting OD and GD after SARS-CoV-2 infection; however, more studies are needed to prove it. OD and GD are common long-term consequences of COVID-19 and influenced by gender, initial severity of dysfunction, emotional distress and depression, and SARS-CoV-2 variants. More studies are needed to illustrate their pathogenesis and to establish therapeutic strategies.


Assuntos
COVID-19 , Transtornos do Olfato , Humanos , Feminino , COVID-19/complicações , COVID-19/epidemiologia , SARS-CoV-2 , Síndrome de COVID-19 Pós-Aguda , Qualidade de Vida , Transtornos do Olfato/epidemiologia , Transtornos do Olfato/etiologia , Transtornos do Olfato/diagnóstico , Distúrbios do Paladar/epidemiologia , Distúrbios do Paladar/etiologia
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