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1.
Proc Natl Acad Sci U S A ; 121(5): e2316914121, 2024 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-38252828

RESUMO

High-performance sodium storage at low temperature is urgent with the increasingly stringent demand for energy storage systems. However, the aggravated capacity loss is induced by the sluggish interfacial kinetics, which originates from the interfacial Na+ desolvation. Herein, all-fluorinated anions with ultrahigh electron donicity, trifluoroacetate (TFA-), are introduced into the diglyme (G2)-based electrolyte for the anion-reinforced solvates in a wide temperature range. The unique solvation structure with TFA- anions and decreased G2 molecules occupying the inner sheath accelerates desolvation of Na+ to exhibit decreased desolvation energy from 4.16 to 3.49 kJ mol-1 and 24.74 to 16.55 kJ mol-1 beyond and below -20 °C, respectively, compared with that in 1.0 M NaPF6-G2. These enable the cell of Na||Na3V2(PO4)3 to deliver 60.2% of its room-temperature capacity and high capacity retention of 99.2% after 100 cycles at -40 °C. This work highlights regulation of solvation chemistry for highly stable sodium-ion batteries at low temperature.

2.
Proc Natl Acad Sci U S A ; 120(23): e2302858120, 2023 06 06.
Artigo em Inglês | MEDLINE | ID: mdl-37252995

RESUMO

Arabinogalactan (AG) is an essential cell wall component in mycobacterial species, including the deadly human pathogen Mycobacterium tuberculosis. It plays a pivotal role in forming the rigid mycolyl-AG-peptidoglycan core for in vitro growth. AftA is a membrane-bound arabinosyltransferase and a key enzyme involved in AG biosynthesis which bridges the assembly of the arabinan chain to the galactan chain. It is known that AftA catalyzes the transfer of the first arabinofuranosyl residue from the donor decaprenyl-monophosphoryl-arabinose to the mature galactan chain (i.e., priming); however, the priming mechanism remains elusive. Herein, we report the cryo-EM structure of Mtb AftA. The detergent-embedded AftA assembles as a dimer with an interface maintained by both the transmembrane domain (TMD) and the soluble C-terminal domain (CTD) in the periplasm. The structure shows a conserved glycosyltransferase-C fold and two cavities converging at the active site. A metal ion participates in the interaction of TMD and CTD of each AftA molecule. Structural analyses combined with functional mutagenesis suggests a priming mechanism catalyzed by AftA in Mtb AG biosynthesis. Our data further provide a unique perspective into anti-TB drug discovery.


Assuntos
Mycobacterium tuberculosis , Humanos , Galactanos , Pentosiltransferases/genética
3.
J Transl Med ; 22(1): 648, 2024 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-38987805

RESUMO

Glioma is the most common malignant tumor in central nervous system, with significant health burdens to patients. Due to the intrinsic characteristics of glioma and the lack of breakthroughs in treatment modalities, the prognosis for most patients remains poor. This results in a heavy psychological and financial load worldwide. In recent years, cannabidiol (CBD) has garnered widespread attention and research due to its anti-tumoral, anti-inflammatory, and neuroprotective properties. This review comprehensively summarizes the preclinical and clinical research on the use of CBD in glioma therapy, as well as the current status of nanomedicine formulations of CBD, and discusses the potential and challenges of CBD in glioma therapy in the future.


Assuntos
Canabidiol , Glioma , Canabidiol/uso terapêutico , Canabidiol/farmacologia , Humanos , Glioma/tratamento farmacológico , Glioma/patologia , Animais , Pesquisa Translacional Biomédica , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/patologia , Nanomedicina/métodos
4.
Inorg Chem ; 63(25): 11821-11831, 2024 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-38848310

RESUMO

A series of ruthenium complexes (Ru1-Ru4) bearing new NNN-pincer ligands were synthesized in 58-78% yields. All of the complexes are air and moisture stable and were characterized by IR, NMR, and high-resolution mass spectra (HRMS). In addition, the structures of Ru1-Ru3 were confirmed by X-ray crystallographic analysis. These Ru(II) complexes exhibited high catalytic efficiency and broad functional group tolerance in the N-methylation reaction of amines using CH3OH as both the C1 source and solvent. Experimental results indicated that the electronic effect of the substituents on the ligands considerably affects the catalytic reactivity of the complexes in which Ru3 bearing an electron-donating OMe group showed the highest activity. Deuterium labeling and control experiments suggested that the dehydrogenation of methanol to generate ruthenium hydride species was the rate-determining step in the reaction. Furthermore, this protocol also provided a ready approach to versatile trideuterated N-methylamines under mild conditions using CD3OD as a deuterated methylating agent.

5.
Phys Chem Chem Phys ; 26(17): 13441-13451, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38647259

RESUMO

Soluble N-glycosyltransferase from Actinobacillus pleuropneumoniae (ApNGT) catalyzes the glycosylation of asparagine residues, and represents one of the most encouraging biocatalysts for N-glycoprotein production. Since the sugar tolerance of ApNGT is restricted to limited monosaccharides (e.g., Glc, GlcN, Gal, Xyl, and Man), tremendous efforts are devoted to expanding the substrate scope of ApNGT via enzyme engineering. However, rational design of novel NGT variants suffers from an elusive understanding of the substrate-binding process from a dynamic point of view. Here, by employing extensive all-atom molecular dynamics (MD) simulations integrated with a kinetic model, we reveal, at the atomic level, the complete donor-substrate binding process from the bulk solvent to the ApNGT active-site, and the key intermediate states of UDP-Glc during its loading dynamics. We are able to determine the critical transition event that limits the overall binding rate, which guides us to pinpoint the key ApNGT residues dictating the donor-substrate entry. The functional roles of several identified gating residues were evaluated through site-directed mutagenesis and enzymatic assays. Two single-point mutations, N471A and S496A, could profoundly enhance the catalytic activity of ApNGT. Our work provides deep mechanistic insights into the structural dynamics of the donor-substrate loading process for ApNGT, which sets a rational basis for design of novel NGT variants with desired substrate specificity.


Assuntos
Actinobacillus pleuropneumoniae , Glicosiltransferases , Simulação de Dinâmica Molecular , Actinobacillus pleuropneumoniae/enzimologia , Actinobacillus pleuropneumoniae/metabolismo , Actinobacillus pleuropneumoniae/genética , Cinética , Especificidade por Substrato , Glicosiltransferases/metabolismo , Glicosiltransferases/química , Glicosiltransferases/genética , Mutagênese Sítio-Dirigida , Domínio Catalítico
6.
Sensors (Basel) ; 24(8)2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38676275

RESUMO

As graphene-related technology advances, the benefits of graphene metamaterials become more apparent. In this study, a surface-isolated exciton-based absorber is built by running relevant simulations on graphene, which can achieve more than 98% perfect absorption at multiple frequencies in the MWIR (MediumWavelength Infra-Red (MWIR) band as compared to the typical absorber. The absorber consists of three layers: the bottom layer is gold, the middle layer is dielectric, and the top layer is patterned with graphene. Tunability was achieved by electrically altering graphene's Fermi energy, hence the position of the absorption peak. The influence of graphene's relaxation time on the sensor is discussed. Due to the symmetry of its structure, different angles of light source incidence have little effect on the absorption rate, leading to polarization insensitivity, especially for TE waves, and this absorber has polarization insensitivity at ultra-wide-angle degrees. The sensor is characterized by its tunability, polarisation insensitivity, and high sensitivity, with a sensitivity of up to 21.60 THz/refractive index unit (RIU). This paper demonstrates the feasibility of the multi-frequency sensor and provides a theoretical basis for the realization of the multi-frequency sensor. This makes it possible to apply it to high-sensitivity sensors.

7.
Angew Chem Int Ed Engl ; 63(3): e202313142, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-37917045

RESUMO

Sodium dual-ion batteries (Na-DIBs) have attracted increasing attention due to their high operative voltages and low-cost raw materials. However, the practical applications of Na-DIBs are still hindered by the issues, such as low capacity and poor Coulombic efficiency, which is highly correlated with the compatibility between electrode and electrolyte but rarely investigated. Herein, fluoroethylene carbonate (FEC) is introduced into the electrolyte to regulate cation/anion solvation structure and the stability of cathode/anode-electrolyte interphase of Na-DIBs. The FEC modulates the environment of PF6 - solvation sheath and facilitates the interaction of PF6 - on graphite. In addition, the NaF-rich interphase caused by the preferential decomposition of FEC effectively inhibits side reactions and pulverization of anodes with the electrolyte. Consequently, Sb||graphite full cells in FEC-containing electrolyte achieve an improved capacity, cycling stability and Coulombic efficiency. This work elucidates the underlying mechanism of bifunctional FEC and provides an alternative strategy of building high-performance dual ion batteries.

8.
J Appl Toxicol ; 43(10): 1522-1532, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37183367

RESUMO

Chemoresistance is still a vital obstacle in various tumors chemotherapy. This study aimed to explore the role of Petite Integration Factor 1 (PIF1) in the sensitivity of gemcitabine response to pancreatic cancer cells. Gene Expression Profiling Interactive Analysis (GEPIA) database was employed for evaluating the level of PIF1 in pancreatic cancer tissues and normal tissues. The mRNA level of PIF1 was detected via reverse transcription-quantitative polymerase chain reaction (RT-qPCR) analysis. The relative protein expression of PIF1, cleaved caspase-3, and phosphorylated histone H2Ax (γH2Ax) was assessed through western blot. Cell viability and apoptosis were assessed via Cell Counting Kit-8 (CCK-8) assay and flow cytometry, respectively. Moreover, lactate dehydrogenase (LDH) release and caspase-3 activity were determined via the corresponding LDH Cytotoxicity Assay Kit and caspase-3 colorimetric assay kit. PIF1 expression was upregulated in pancreatic cancer tissues and cells. Knockdown of PIF1 exhibited the repressive impact on the viability of AsPC-1 and PANC-1 cells. PIF1 knockdown enhanced LDH release and apoptosis in both AsPC-1 and PANC-1 cells. PIF1 downregulation could augment the sensitivity of gemcitabine in pancreatic cancer cells, as evidenced by lower cell viability and higher LDH release and apoptosis rate after knocking down PIF1 in gemcitabine-treated pancreatic cancer cells relative to pancreatic cancer cells treated with gemcitabine alone. Moreover, PIF1 knockdown increased γH2Ax protein expression and DNA damage, and gemcitabine treatment-induced DNA damage in AsPC-1 and PANC-1 cells was exacerbated by PIF1 silencing. Furthermore, gemcitabine treatment-caused increase of DNA damage was alleviated by PIF1 overexpression; whereas, this effect of PIF1 upregulation was reversed by thymidine, a DNA synthesis inhibitor. In addition, the decreased gemcitabine sensitivity response to pancreatic cancer cells caused by PIF1 upregulation was also hindered by thymidine treatment. In conclusion, PIF1 silencing enhanced gemcitabine sensitivity response to pancreatic cancer cells through aggrandizing DNA damage.


Assuntos
Gencitabina , Neoplasias Pancreáticas , Humanos , Apoptose , Caspase 3/genética , Caspase 3/metabolismo , Linhagem Celular Tumoral , Desoxicitidina/farmacologia , Dano ao DNA , Resistencia a Medicamentos Antineoplásicos/genética , Neoplasias Pancreáticas/tratamento farmacológico , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/metabolismo , Neoplasias Pancreáticas
9.
Int J Mol Sci ; 24(10)2023 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-37240123

RESUMO

Abscisic acid (ABA) plays an important role in the response of plants to drought stress. However, the chemical structure of ABA is unstable, which severely limits its application in agricultural production. Here, we report the identification of a small molecule compound of tetrazolium as an ABA analog (named SLG1) through virtual screening. SLG1 inhibits the seedling growth and promotes drought resistance of Arabidopsis thaliana with higher stability. Yeast two-hybrid and PP2C inhibition assays show that SLG1 acts as a potent activator of multiple ABA receptors in A. thaliana. Results of molecular docking and molecular dynamics show that SLG1 mainly binds to PYL2 and PYL3 through its tetrazolium group and the combination is stable. Together, these results demonstrate that SLG1, as an ABA analogue, protects A. thaliana from drought stress. Moreover, the newly identified tetrazolium group of SLG1 that binds to ABA receptors can be used as a new option for structural modification of ABA analogs.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Arabidopsis/metabolismo , Ácido Abscísico/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Resistência à Seca , Simulação de Acoplamento Molecular , Secas , Proteínas de Transporte/metabolismo , Regulação da Expressão Gênica de Plantas , Receptores de Superfície Celular/metabolismo
10.
Molecules ; 28(21)2023 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-37959825

RESUMO

The treatment of 2-(ArNC(H))C6H4-HNC9H6N with n-BuLi and the subsequent addition of CuCl2 afforded the anilido-aldimine Cu(II) complexes 1-5 Cu[{2-[ArN=C(H)]C6H4}N(8-C9H6N)]Cl (Ar = 2,6-iPr2C6H3 (1), 2,4,6-(CH3)3C6H2 (2), 4-OCH3C6H4 (3), 4-BrC6H4 (4), 4-ClC6H4 (5)), respectively. All the copper complexes were fully characterized by IR, EPR and HR-MS spectra. The X-ray diffraction analysis reveals that 2 and 4 are mononuclear complexes, and the Cu atom is sitting in a slightly square-planar geometry. These Cu(II) complexes have exhibited excellent catalytic activity in the Chan-Lam coupling reactions of benzimidazole derivatives with arylboronic acids, achieving the highest yields of up to 96%.

11.
Angew Chem Int Ed Engl ; 62(39): e202308888, 2023 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-37530650

RESUMO

High-voltage lithium-ion batteries (LIBs) have attracted great attention due to their promising high energy density. However, severe capacity degradation is witnessed, which originated from the incompatible and unstable electrolyte-electrode interphase at high voltage. Herein, a robust additive-induced sulfur-rich interphase is constructed by introducing an additive with ultrahigh S-content (34.04 %, methylene methyl disulfonate, MMDS) in 4.6 V LiNi0.5 Co0.2 Mn0.3 O2 (NCM523)||graphite pouch cell. The MMDS does not directly participate the inner Li+ sheath, but the strong interactions between MMDS and PF6 - anions promote the preferential decomposition of MMDS and broaden the oxidation stability, facilitating the formation of an ultrathin but robust sulfur-rich interfacial layer. The electrolyte consumption, gas production, phase transformation and dissolution of transition metal ions were effectively inhibited. As expected, the 4.6 V NCM523||graphite pouch cell delivers a high capacity retention of 87.99 % even after 800 cycles. This work shares new insight into the sulfur-rich additive-induced electrolyte-electrode interphase for stable high-voltage LIBs.

12.
Mol Cell Biochem ; 477(7): 1947-1957, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35362843

RESUMO

Anti-silencing function 1B (ASF1B) has been reported to be associated with the occurrence of many kinds of tumors. However, the biological effect and action mechanism of ASF1B in pancreatic cancer (PC) tumorigenesis remain unclear. The expression and prognosis value of ASF1B in PC were analyzed using GEPIA, GEO, and Kaplan-Meier plotter databases. The diagnostic value of ASF1B in PC was determined by receiver operating characteristic curve. The relationship between ASF1B expression and the clinical feathers in PC was investigated based on TCGA. qRT-PCR and western blot analyses were used to measure ASF1B expression in PC cells. Cell proliferation was evaluated by MTT and EdU assays, and apoptosis was examined by TUNEL and caspase-3 activity assays. Western blot analysis was utilized to detect the expression of proliferating cell nuclear antigen (PCNA), cyclin D1, Bax, Bcl-2, and phosphatidylinositol 3-kinase (PI3K)/protein kinase B (Akt) signaling proteins. ASF1B was overexpressed in several digestive cancers, including PC. Upregulated ASF1B was correlated with the poor prognosis and clinical features in PC patients. The area under the curve (AUC) value of ASF1B was 0.990. ASF1B was also overexpressed in PC cells. ASF1B silencing inhibited PC cell proliferation, promoted apoptosis, and increased caspase-3 activity, which were accompanied by the reduction of PCNA and cyclin D1 expression and increase of the ratio of Bax/Bcl-2 expression. Additionally, ASF1B silencing suppressed the PI3K/Akt pathway and 740Y-P treatment partially abolished the effects of ASF1B knockdown on PC cells. In conclusion, ASF1B silencing retarded proliferation and promoted apoptosis in PC cells by inactivation of the PI3K/Akt pathway.


Assuntos
Proteínas de Ciclo Celular , Neoplasias Pancreáticas , Apoptose/fisiologia , Carcinogênese/genética , Caspase 3/metabolismo , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Linhagem Celular Tumoral , Proliferação de Células , Ciclina D1/metabolismo , Humanos , Neoplasias Pancreáticas/patologia , Fosfatidilinositol 3-Quinases/metabolismo , Antígeno Nuclear de Célula em Proliferação/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais , Proteína X Associada a bcl-2/genética , Neoplasias Pancreáticas
13.
J Org Chem ; 87(19): 12596-12607, 2022 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-36162131

RESUMO

We present a convenient and efficient protocol to synthesize quinolines and quinazolines in one pot under mild conditions. A variety of substituted quinolines were synthesized in good to excellent yields (up to 97% yield) from the dehydrogenative cyclizations of 2-aminoaryl alcohols and ketones catalyzed by readily available Co(OAc)2·4H2O. This cobalt catalytic system also showed high activity in the reactions of 2-aminobenzyl alcohols with nitriles, affording various quinazoline derivatives (up to 95% yield). The present protocol offers an environmentally benign approach for the synthesis of N-heterocycles by employing an earth-abundant cobalt salt under ligand-free conditions.

14.
Andrologia ; 54(1): e14287, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34755909

RESUMO

In this study, we aimed to investigate the effect of gap junction (GJ) on apoptosis of smooth muscle. Forty adult male guinea pigs were randomly divided into four groups with 10 guinea pigs in each group. Adeno-associated virus (AAV) and Gap27 were injected at the root of the corpus cavernosum. Two weeks later, the corpus cavernosum tissue was taken to be tested. The expression of Cx43 and α-SMC protein was detected by immunofluorescence and Western blotting. The content of corpus cavernosum smooth muscle was detected by Masson trichrome staining. Apoptosis was detected by TUNEL staining and Western blotting. The results showed that Gap27 did not affect Cx43 but decreased the expression of smooth muscle. The results of TUNEL staining and detection of apoptosis-related proteins showed that apoptosis was induced by Gap27. In addition, we found that corpus cavernosum injection of AAV could induce obvious apoptosis. In this study, we examined the effect of inhibition of gap junction on smooth muscle, and suggested that the decrease of gap junction function may be a potential mechanism of smooth muscle apoptosis.


Assuntos
Disfunção Erétil , Miócitos de Músculo Liso , Animais , Apoptose , Comunicação , Junções Comunicantes , Cobaias , Humanos , Masculino , Músculo Liso , Pênis , Ratos , Ratos Sprague-Dawley
15.
Curr Issues Mol Biol ; 43(3): 1889-1905, 2021 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-34889903

RESUMO

Subterranean rodents could maintain their normal activities in hypoxic environments underground. Eospalax fontanierii, as one kind of subterranean rodent found in China can survive very low oxygen concentration in labs. It has been demonstrated that long non-coding RNAs (lncRNAs) have important roles in gene expression regulations at different levels and some lncRNAs were found as hypoxia-regulated lncRNAs in cancers. We predicted thousands of lncRNAs in the liver and heart tissues by analyzing RNA-Seq data in Eospalax fontanierii. Those lncRNAs often have shorter lengths, lower expression levels, and lower GC contents than mRNAs. Majors of lncRNAs have expression peaks in hypoxia conditions. We found 1128 DE-lncRNAs (differential expressed lncRNAs) responding to hypoxia. To search the miRNA regulation network for lncRNAs, we predicted 471 and 92 DE-lncRNAs acting as potential miRNA target and target mimics, respectively. We also predicted the functions of DE-lncRNAs based on the co-expression networks of lncRNA-mRNA. The DE-lncRNAs participated in the functions of biological regulation, signaling, development, oxoacid metabolic process, lipid metabolic/biosynthetic process, and catalytic activity. As the first study of lncRNAs in Eospalax fontanierii, our results show that lncRNAs are popular in transcriptome widely and can participate in multiple biological processes in hypoxia responses.


Assuntos
Regulação da Expressão Gênica , Hipóxia/genética , RNA Longo não Codificante/genética , Roedores/genética , Animais , Biologia Computacional/métodos , Perfilação da Expressão Gênica , Redes Reguladoras de Genes , Hipóxia/metabolismo , MicroRNAs/genética , RNA Mensageiro/genética , Roedores/metabolismo , Transcriptoma
16.
Bioorg Chem ; 115: 105271, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34426155

RESUMO

In this study, a novel batch of thiazole-containing mitochondrial targeting agents were designed and synthesized. Four kinds of mitochondrial targeting moieties and six kinds of linkers were designed. Their structures were confirmed by NMR and HR-MS. The screening of antiproliferative activity revealed that most compounds displayed cytotoxicity on HeLa cancer cell. In particular, D1 has an IC50 value of 35.32 µmol·L-1 against HeLa cell. In addition, cellular respiratory activities were also tested on HeLa cancer cells. D1 had a basal oxygen consumption rate of 8.84 pmol·s-1·mL-1. Also, D1 inhibited the mitochondrial respiration of HeLa cell significantly at 5 µmol·L-1, as well as a complete inhibitory of oxygen consumption for cellular ATP coupling. Furthermore, the pKa, logP, and logD under different pH conditions of all the compounds were calculated by the ACD/Percepta-PhysChem Suite, and the results manifested the correlation between physicochemical properties and chemical activity of compounds. The results identify D1 as a promising mitochondria inhibitor and anticancer agent with appropriate physicochemical properties.


Assuntos
Antineoplásicos/farmacologia , Desenho de Fármacos , Mitocôndrias/efeitos dos fármacos , Tiazóis/farmacologia , Antineoplásicos/síntese química , Antineoplásicos/química , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Células HeLa , Humanos , Mitocôndrias/metabolismo , Estrutura Molecular , Relação Estrutura-Atividade , Tiazóis/síntese química , Tiazóis/química
17.
Int J Mol Sci ; 22(2)2021 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-33435353

RESUMO

Selaginella moellendorffii is a lycophyte, a member of an ancient vascular plant lineage. Two distinct types of terpene synthase (TPS) genes were identified from this species, including S. moellendorffii TPS genes (SmTPSs) and S. moellendorffii microbial TPS-like genes (SmMTPSLs). The goal of this study was to investigate the biochemical functions of SmMTPSLs. Here, eight full-length SmMTPSL genes (SmMTPSL5, -15, -19, -23, -33, -37, -46, and -47) were functionally characterized from S. moellendorffii. Escherichia coli-expressed recombinant SmMTPSLs were tested for monoterpenes synthase and sesquiterpenes synthase activities. These enzymatic products were typical monoterpenes and sesquiterpenes that have been previous shown to be generated by typical plant TPSs when provided with geranyl diphosphate (GPP) and farnesyl diphosphate (FPP) as the substrates. Meanwhile, SmMTPSL23, -33, and -37 were up-regulated when induced by alamethicin (ALA) and methyl jasmonate (MeJA), suggesting a role for these genes in plants response to abiotic stresses. Furthermore, this study pointed out that the terpenoids products of SmMTPSL23, -33, and -37 have an antibacterial effect on Pseudomonas syringae pv. tomato DC3000 and Staphylococcus aureus. Taken together, these results provide more information about the catalytic and biochemical function of SmMTPSLs in S. moellendorffii plants.


Assuntos
Alquil e Aril Transferases/metabolismo , Proteínas de Plantas/metabolismo , Selaginellaceae/metabolismo , Terpenos/metabolismo , Alquil e Aril Transferases/química , Alquil e Aril Transferases/genética , Regulação da Expressão Gênica de Plantas , Genoma de Planta , Simulação de Acoplamento Molecular , Filogenia , Proteínas de Plantas/química , Proteínas de Plantas/genética , Fosfatos de Poli-Isoprenil/metabolismo , Conformação Proteica , Selaginellaceae/química , Selaginellaceae/genética , Sesquiterpenos/metabolismo
18.
Sensors (Basel) ; 20(22)2020 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-33187213

RESUMO

A novel piezoceramic stack-based smart aggregate (PiSSA) with piezoceramic wafers in series or parallel connection is developed to increase the efficiency and output performance over the conventional smart aggregate with only one piezoelectric patch. Due to the improvement, PiSSA is suitable for situations where the stress waves easily attenuate. In PiSSA, the piezoelectric wafers are electrically connected in series or parallel, and three types of piezoelectric wafers with different electrode patterns are designed for easy connection. Based on the theory of piezo-elasticity, a simplified one-dimensional model is derived to study the electromechanical, transmitting and sensing performance of PiSSAs with the wafers in series and parallel connection, and the model was verified by experiments. The theoretical results reveal that the first resonance frequency of PiSSAs in series and parallel decreases as the number or thickness of the PZT wafers increases, and the first electromechanical coupling factor increases firstly and then decrease gradually as the number or thickness increases. The results also show that both the first resonance frequency and the first electromechanical coupling factor of PiSSA in series and parallel change no more than 0.87% as the Young's modulus of the epoxy increases from 0.5 to 1.5 times 3.2 GPa, which is helpful for the fabrication of PiSSAs. In addition, the displacement output of PiSSAs in parallel is about 2.18-22.49 times that in series at 1-50 kHz, while the voltage output of PiSSAs in parallel is much less than that in parallel, which indicates that PiSSA in parallel is much more suitable for working as an actuator to excite stress waves and PiSSA in series is suitable for working as a sensor to detect the waves. All the results demonstrate that the connecting type, number and thickness of the PZT wafers should be carefully selected to increase the efficiency and output of PiSSA actuators and sensors. This study contributes to providing a method to investigate the characteristics and optimize the structural parameters of the proposed PiSSAs.

19.
Mol Biol Rep ; 46(6): 5671-5683, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31552593

RESUMO

With the increase in blood viscosity, the blood circulation resistance will increase when animals are in hypoxia. However, these phenomenons do not appear in hypoxic-adapted animals. Eospalax fontanierii is a subterranean rodent and is an ideal species for research in hypoxia adaptation. Eighteen healthy adult E. fontanierii individuals were equally divided into three groups that were exposed to 21% O2 for 1 week, 10.5% O2 for 44 h, and 6.5% O2 for 6 h, and then, the hearts were collected for transcriptome sequencing. After differentially expressed analysis, fibrinogen genes were selected for qPCR and Western blot verification. Eighteen healthy adult Sprague-Dawley rats (SD rats) were treated with the same oxygen concentrations, and their hearts were simultaneously subjected to qPCR. The quantitative real-time PCR and Western blot results were completely opposite to those of the rats. E. fontanierii fibrinogen mRNA was significantly downregulated when expressed under the conditions of 10.5% and 6.5% O2 compared with 21% O2. Correspondingly, fibrinogen mRNA in E. fontanierii was expressed at lower levels than SD rats in 10.5% and 6.5% O2. After tail-cutting experiment, the results showed that the coagulation rate of E. fontanierii was slowed down under hypoxic conditions. These results showed that E. fontanierii may downregulate the expression of fibrinogen mRNA in hypoxia to reduce the aggregation of red blood cells and platelets in plasma, which may prevent blood from becoming overly viscous, and at the same time, reduce blood circulation resistance and the probability of thrombosis in hypoxia to protect the heart.


Assuntos
Fibrinogênio , Hipóxia/genética , Miocárdio/metabolismo , Roedores , Transcriptoma/genética , Animais , Bases de Dados Genéticas , Regulação para Baixo/genética , Ecossistema , Fibrinogênio/genética , Fibrinogênio/metabolismo , Hipóxia/metabolismo , Miocárdio/química , Oxigênio/metabolismo , RNA Mensageiro/análise , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ratos , Ratos Sprague-Dawley , Roedores/genética , Roedores/fisiologia , Análise de Sequência de RNA , Transcriptoma/fisiologia
20.
Anal Chem ; 88(4): 2234-42, 2016 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-26757347

RESUMO

Metabolomics is increasingly applied to discover and validate metabolite biomarkers and illuminate biological variations. Combination of multiple analytical batches in large-scale and long-term metabolomics is commonly utilized to generate robust metabolomics data, but gross and systematic errors are often observed. The appropriate calibration methods are required before statistical analyses. Here, we develop a novel correction strategy for large-scale and long-term metabolomics study, which could integrate metabolomics data from multiple batches and different instruments by calibrating gross and systematic errors. The gross error calibration method applied various statistical and fitting models of the feature ratios between two adjacent quality control (QC) samples to screen and calibrate outlier variables. Virtual QC of each sample was produced by a linear fitting model of the feature intensities between two neighboring QCs to obtain a correction factor and remove the systematic bias. The suggested method was applied to handle metabolic profiling data of 1197 plant samples in nine batches analyzed by two gas chromatography-mass spectrometry instruments. The method was evaluated by the relative standard deviations of all the detected peaks, the average Pearson correlation coefficients, and Euclidean distance of QCs and non-QC replicates. The results showed the established approach outperforms the commonly used internal standard correction and total intensity signal correction methods, it could be used to integrate the metabolomics data from multiple analytical batches and instruments, and it allows the frequency of QC to one injection of every 20 real samples. The suggested method makes a large amount of metabolomics analysis practicable.


Assuntos
Cromatografia Gasosa-Espectrometria de Massas , Metabolômica/métodos , Calibragem , Controle de Qualidade
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