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1.
Artigo em Inglês | MEDLINE | ID: mdl-38825349

RESUMO

BACKGROUND: Biomarkers of neuronal, glial cells and inflammation in traumatic brain injury (TBI) are available but they do not specifically reflect the damage to synapses, which represent the bulk volume of the brain. Experimental models have demonstrated extensive involvement of synapses in acute TBI, but biomarkers of synaptic damage in human patients have not been explored. METHODS: Single-molecule array assays were used to measure synaptosomal-associated protein-25 (SNAP-25) and visinin-like protein 1 (VILIP-1) (along with neurofilament light chain (NFL), ubiquitin carboxy-terminal hydrolase L1 (UCH-L1), glial fibrillar acidic protein (GFAP), interleukin-6 (IL-6) and interleukin-8 (IL-8)) in ventricular cerebrospinal fluid (CSF) samples longitudinally acquired during the intensive care unit (ICU) stay of 42 patients with severe TBI or 22 uninjured controls. RESULTS: CSF levels of SNAP-25 and VILIP-1 are strongly elevated early after severe TBI and decline in the first few days. SNAP-25 and VILIP-1 correlate with inflammatory markers at two distinct timepoints (around D1 and then again at D5) in follow-up. SNAP-25 and VILIP-1 on the day-of-injury have better sensitivity and specificity for unfavourable outcome at 6 months than NFL, UCH-L1 or GFAP. Later elevation of SNAP-25 was associated with poorer outcome. CONCLUSION: Synaptic damage markers are acutely elevated in severe TBI and predict long-term outcomes, as well as, or better than, markers of neuroaxonal injury. Synaptic damage correlates with initial injury and with a later phase of secondary inflammatory injury.

2.
Ecotoxicol Environ Saf ; 271: 115975, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38244514

RESUMO

Polycyclic aromatic hydrocarbons (PAHs) are ubiquitous at relatively high concentrations by atmospheric deposition, and they are threatening to the environment. In this study, the toxicity of naphthalene on tall fescue and its potential responding mechanism was first studied by integrating approaches. Tall fescue seedlings were exposed to 0, 20, and 100 mg L-1 naphthalene in a hydroponic environment for 9 days, and toxic effects were observed by the studies of general physiological studies, chlorophyll fluorescence, and root morphology. Additionally, Ultra Performance Liquid Chromatography - Electrospray Ionization - High-Resolution Mass Spectrometry (UPLC-ESI-HRMS) was used to depict metabolic profiles of tall fescue under different exposure durations of naphthalene, and the intrinsic molecular mechanism of tall fescue resistance to abiotic stresses. Tall fescue shoots were more sensitive to the toxicity of naphthalene than roots. Low-level exposure to naphthalene inhibited the electron transport from the oxygen-evolving complex (OEC) to D1 protein in tall fescue shoots but induced the growth of roots. Naphthalene induced metabolic change of tall fescue roots in 12 h, and tall fescue roots maintained the level of sphingolipids after long-term exposure to naphthalene, which may play important roles in plant resistance to abiotic stresses.


Assuntos
Festuca , Lolium , Hidrocarbonetos Policíclicos Aromáticos , Festuca/metabolismo , Naftalenos/metabolismo , Hidrocarbonetos Policíclicos Aromáticos/metabolismo , Lolium/metabolismo , Espectrometria de Massas
3.
Genes Dev ; 30(14): 1636-44, 2016 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-27445394

RESUMO

Hepatocyte nuclear factor 6 (HNF6) is required for liver development, but its role in adult liver metabolism is not known. Here we show that deletion of HNF6 in livers of adult C57Bl/6 mice leads to hepatic steatosis in mice fed normal laboratory chow. Although HNF6 is known mainly as a transcriptional activator, hepatic loss of HNF6 up-regulated many lipogenic genes bound directly by HNF6. Many of these genes are targets of the circadian nuclear receptor Rev-erbα, and binding of Rev-erbα at these sites was lost when HNF6 was ablated in the liver. While HNF6 and Rev-erbα coordinately regulate hepatic lipid metabolism, each factor also affects additional gene sets independently. These findings highlight a novel mechanism of transcriptional repression by HNF6 and demonstrate how overlapping and distinct mechanisms of transcription factor function contribute to the integrated physiology of the liver.


Assuntos
Regulação da Expressão Gênica/genética , Fator 6 Nuclear de Hepatócito/genética , Fator 6 Nuclear de Hepatócito/metabolismo , Metabolismo dos Lipídeos/genética , Fígado/metabolismo , Fígado/fisiopatologia , Membro 1 do Grupo D da Subfamília 1 de Receptores Nucleares/metabolismo , Animais , Fígado Gorduroso/genética , Deleção de Genes , Técnicas de Inativação de Genes , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Membro 1 do Grupo D da Subfamília 1 de Receptores Nucleares/genética , Ligação Proteica/genética
4.
Small ; 19(34): e2301975, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37165580

RESUMO

Oxygen doping is an effective strategy for constructing high-performance carbon anodes in Na ion batteries; however, current oxygen-doped carbons always exhibit low doping levels and high-defect surfaces, resulting in limited capacity improvement and low initial Coulombic efficiency (ICE). Herein, a stainless steel-assisted high-energy ball milling is exploited to achieve high-level oxygen doping (19.33%) in the carbon framework. The doped oxygen atoms exist dominantly in the form of carbon-oxygen double bonds, supplying sufficient Na storage sites through an addition reaction. More importantly, it is unexpected that the random carbon layers on the surface are reconstructed into a quasi-ordered arrangement by robust mechanical force, which is low-defect and favorable for suppressing the formation of thick solid electrolyte interfaces. As such, the obtained carbon presents a large reversible capacity of 363 mAh g-1 with a high ICE up to 83.1%. In addition, owing to the surface-dominated capacity contribution, an ultrafast Na storage is achieved that the capacity remains 139 mAh g-1 under a large current density of 100 A g-1 . Such good Na storage performance, especially outstanding rate capability, has rarely been achieved before.

5.
Phys Chem Chem Phys ; 25(10): 7213-7222, 2023 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-36846920

RESUMO

Selenium (Se) is an ideal doping agent to modulate the structure of carbon materials to improve their sodium storage performance but has been rarely investigated. In the present study, a novel Se-doped honeycomb-like macroporous carbon (Se-HMC) is prepared by a surface crosslinking method using diphenyl diselenide as the carbon source and SiO2 nanospheres as the template. Se-HMC has a high Se weight percentage above 10%, with a large surface area of 557 m2 g-1. Owing to the well-developed porous structure in combination with Se-assisted capacitive redox reactions, Se-HMC exhibits surface-dominated Na storage behaviors, thus presenting large capacity and fast Na storage capability. To be specific, Se-HMC delivers a high reversible capacity of 335 mA h g-1 at 0.1 A g-1, and after an 800-cycle repeated charge/discharge test at 1 A g-1, the capacity is stable with no dramatic loss. Remarkably, the capacity remains 251 mA h g-1 under a very large current density of 5 A g-1 (≈20 C), demonstrating an ultrafast Na storage process. As far as we know, such a good rate performance has been rarely achieved for carbon anodes before.

6.
J Nat Prod ; 86(7): 1736-1745, 2023 07 28.
Artigo em Inglês | MEDLINE | ID: mdl-37436927

RESUMO

In our ongoing study of fungal bioactive natural products, 12 previously undescribed triquinane sesquiterpene glycosides, namely, antrodizonatins A-L (1-12), and four known compounds (13-16) have been obtained from the fermentation of the basidiomycete Antrodiella zonata. The structures were established unambiguously via extensive spectroscopic analysis and theoretical calculations of electronic circular dichroism spectra. This is the first report of triquinane sesquiterpene glycosides. Compounds 1, 5, and 12 displayed antibacterial activity against Staphylococcus aureus with MIC50 values of 35, 34, and 69 µM, respectively.


Assuntos
Basidiomycota , Polyporales , Sesquiterpenos , Glicosídeos/farmacologia , Glicosídeos/química , Sesquiterpenos/farmacologia , Sesquiterpenos/química , Basidiomycota/química , Estrutura Molecular
7.
J Asian Nat Prod Res ; 25(5): 497-502, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-34806497

RESUMO

(-)-5-Methylmellein (1) and its new dimer (2) were isolated from cultures of the basidiomycete Inonotus sinensis. Their structures were elucidated on the basis of extensive spectroscopic methods including UV, IR, HR-EI-MS, 1D NMR and 2D NMR. The structure of Compound 2 was determined by single-crystal X-ray crystallographic analysis. Compound 2 was tested for the cytotoxicities against five human cancer cell lines.


Assuntos
Basidiomycota , Inonotus , Humanos , Estrutura Molecular , Basidiomycota/química , Linhagem Celular Tumoral
8.
Molecules ; 28(16)2023 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-37630261

RESUMO

Cooking methods affect the compositions of Lentinus edodes metabolites. Nevertheless, little information is available on the specific impact of different cooking methods on Lentinus edodes via metabolomic analysis. This study determined the influence of boiling, steaming, air-frying, and roasting on the metabolomic profiles of Lentinus edodes based on UHPLC-Q-Exactive Orbitrap MS/MS in combination with chemometrics. A total of 990 metabolites were detected and classified into 11 super-classes. Subsequently, the metabolites of the four cooking methods were distinguished using multivariate statistical analysis. The results showed that boiling caused a massive loss of metabolites while roasting and air-frying led to an evident upregulation. The upregulation of metabolites in the steaming groups was not as significant as in roasting and air-frying. This study provided reference data for a comprehensive understanding of the metabolites associated with domestic cooking methods and valuable guidance for the development of Lentinus edodes and its products in the future.


Assuntos
Quimiometria , Cogumelos Shiitake , Espectrometria de Massas em Tandem , Metabolômica , Vapor , Culinária
9.
Molecules ; 28(12)2023 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-37375146

RESUMO

The Paeonia suffruticosa, known as 'Feng Dan', has been used for thousands of years in traditional Chinese medicine. In our chemical investigation on the root bark of the plant, five new phenolic dimers, namely, paeobenzofuranones A-E (1-5), were characterized. Their structures were determined using spectroscopic analysis including 1D and 2D NMR, HRESIMS, UV, and IR, as well as ECD calculations. Compounds 2, 4, and 5 showed cytotoxicity against three human cancer cell lines, with IC50 values ranging from 6.7 to 25.1 µM. Compounds 1 and 2 showed certain inhibitory activity on NO production. To the best of our knowledge, the benzofuranone dimers and their cytotoxicity of P. suffruticosa are reported for the first time in this paper.


Assuntos
Paeonia , Humanos , Paeonia/química , Fenóis/farmacologia , Fenóis/análise , Espectroscopia de Ressonância Magnética , Raízes de Plantas/química
10.
Molecules ; 28(6)2023 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-36985677

RESUMO

The ethnobotanical plant Marsdenia tenacissima has been used for hundreds of years for Dai people in Yunnan Province, China. Previously, chemical investigations on this plant have revealed that pregnane glycosides were the main biological constituents. Nine new pregnane glycosides, marsdeosides A-I (1-9), were isolated from cultivated dried stems of the medicinal plant Marsdenia tenacissima in this study. The structures were analyzed by extensive spectroscopic analysis, including 1D, 2D NMR, HRESIMS, and IR spectroscopic analysis. The absolute configurations of the sugar moieties were identified by comparing the Rf values and specific optical rotations with those of the commercially available standard samples and the data reported in the literature. Marsdeosides A (1) featured an unusual 8,14-seco-pregnane skeleton. Compounds 1, 8, and 9 showed activity against nitric oxide production in lipopolysaccharide-activated macrophage RAW264.7, with IC50 values of 37.5, 38.8, and 42.8 µM (L-NMMA was used as a positive control, IC50 39.3 µM), respectively. This study puts the knowledge of the chemical profile of the botanical plant M. tenacissima one step forward and, thereby, promotes the sustainable utilization of the resources of traditional folk medicinal plants.


Assuntos
Marsdenia , Plantas Medicinais , Humanos , Plantas Medicinais/química , Marsdenia/química , China , Pregnanos/química , Glicosídeos/química
11.
Infect Immun ; 90(4): e0002222, 2022 04 21.
Artigo em Inglês | MEDLINE | ID: mdl-35311580

RESUMO

Multivalent O-antigen polysaccharide glycoconjugate vaccines are under development to prevent invasive infections caused by pathogenic Enterobacteriaceae. Sequence type 131 (ST131) Escherichia coli of serotype O25b has emerged as the predominant lineage causing invasive multidrug-resistant extraintestinal pathogenic E. coli (ExPEC) infections. We observed the prevalence of E. coli O25b ST131 among a contemporary collection of isolates from U.S. bloodstream infections from 2013 to 2016 (n = 444) and global urinary tract infections from 2014 to 2017 (n = 102) to be 25% and 24%, respectively. To maximize immunogenicity of the serotype O25b O antigen, we investigated glycoconjugate properties, including CRM197 carrier protein cross-linking (single-end versus cross-linked "lattice") and conjugation chemistry (reductive amination chemistry in dimethyl sulfoxide [RAC/DMSO] versus ((2-((2-oxoethyl)thio)ethyl)carbamate [eTEC] linker). Using opsonophagocytic assays (OPAs) to measure serum functional antibody responses to vaccination, we observed that higher-molecular-mass O25b long-chain lattice conjugates showed improved immunogenicity in mice compared with long- or short-chain O antigens conjugated via single-end attachment. The lattice conjugates protected mice from lethal challenge with acapsular O25b ST131 strains as well as against hypervirulent O25b isolates expressing K5 or K100 capsular polysaccharides. A single 1-µg dose of long-chain O25b lattice conjugate constructed with both chemistries also elicited robust serum IgG and OPA responses in cynomolgus macaques. Our findings show that key properties of the O-antigen carrier protein conjugate such as saccharide epitope density and degree of intermolecular cross-linking can significantly enhance functional immunogenicity.


Assuntos
Infecções por Escherichia coli , Antígenos O , Animais , Proteínas de Transporte , Escherichia coli , Infecções por Escherichia coli/prevenção & controle , Glicoconjugados , Camundongos
12.
Anal Chem ; 94(20): 7255-7263, 2022 05 24.
Artigo em Inglês | MEDLINE | ID: mdl-35510918

RESUMO

Stable isotope-assisted metabolomics (SIAM) enables global tracking of isotopic labels in nontargeted metabolomics in living organisms. However, its application in tracking transformation products (TPs, as metabolites of contaminants) of environmental contaminants is still a challenge due to limits in methodology, unmatured algorithms, and the high cost of 13C-labeled contaminants. Therefore, we developed a 2H-SIAM pipeline coupled with a highly flexible algorithm 2H-SIAM(1.0) (https://github.com/kechen1984/2H-SIAM), facilitating tracking TPs of contaminants in the environmental matrix. A detailed discussion illustrates the theory, behavior, and prospect of 2H-SIAM. We demonstrate that the proposed 2H-SIAM pipeline has unique advantages over 13C-SIAM, for example, cost-effective 2H-labeled contaminants, easy synthesis of 2H-labeled emerging contaminants, and providing more structural information. A pyrene soil degradation study further confirmed its high performance. It efficiently discarded 99% of noise signals and extracted 52 features from the nontargeted high resolution mass spectrometry (HRMS) data. Among them, 13 features were annotated as TPs of pyrene with identification confidence from Level 2a to Level 5, and 5 TPs were reported for the first time. In conclusion, the proposed 2H-SIAM pipeline is powerful in tracking potential TPs of environmental contaminants with unique advantages.


Assuntos
Isótopos , Metabolômica , Espectrometria de Massas , Pirenos
13.
J Neuroinflammation ; 19(1): 279, 2022 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-36403069

RESUMO

BACKGROUND: Traumatic brain injury (TBI) is characterized by massive changes in neuronal excitation, from acute excitotoxicity to chronic hyper- or hypoexcitability. Nuclear calcium signaling pathways are involved in translating changes in synaptic inputs and neuronal activity into discrete transcriptional programs which not only affect neuronal survival and synaptic integrity, but also the crosstalk between neurons and glial cells. Here, we report the effects of blunting neuronal nuclear calcium signals in the context of TBI. METHODS: We used AAV vectors to express the genetically encoded and nuclear-targeted calcium buffer parvalbumin (PV.NLS.mCherry) or the calcium/calmodulin buffer CaMBP4.mCherry in neurons only. Upon TBI, the extent of neuroinflammation, neuronal death and synaptic loss were assessed by immunohistochemistry and targeted transcriptome analysis. Modulation of the overall level of neuronal activity was achieved by PSAM/PSEM chemogenetics targeted to parvalbumin interneurons. The functional impact of neuronal nuclear calcium buffering in TBI was assessed by quantification of spontaneous whisking. RESULTS: Buffering neuronal nuclear calcium unexpectedly resulted in a massive and long-lasting increase in the recruitment of reactive microglia to the injury site, which was characterized by a disease-associated and phagocytic phenotype. This effect was accompanied by a substantial surge in synaptic loss and significantly reduced whisking activity. Transcriptome analysis revealed a complex effect of TBI in the context of neuronal nuclear calcium buffering, with upregulation of complement factors, chemokines and interferon-response genes, as well as the downregulation of synaptic genes and epigenetic regulators compared to control conditions. Notably, nuclear calcium buffering led to a substantial loss in neuronal osteoprotegerin (OPG), whereas stimulation of neuronal firing induced OPG expression. Viral re-expression of OPG resulted in decreased microglial recruitment and synaptic loss. OPG upregulation was also observed in the CSF of human TBI patients, underscoring its translational value. CONCLUSION: Neuronal nuclear calcium signals regulate the degree of microglial recruitment and reactivity upon TBI via, among others, osteoprotegerin signals. Our findings support a model whereby neuronal activity altered after TBI exerts a powerful impact on the neuroinflammatory cascade, which in turn contributes to the overall loss of synapses and functional impairment.


Assuntos
Lesões Encefálicas Traumáticas , Microglia , Humanos , Microglia/metabolismo , Sinalização do Cálcio , Parvalbuminas/metabolismo , Cálcio/metabolismo , Osteoprotegerina/metabolismo , Lesões Encefálicas Traumáticas/metabolismo
14.
Langmuir ; 38(23): 7331-7340, 2022 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-35652688

RESUMO

Hard carbon is considered one of the most promising anode candidates for sodium ion batteries but suffers from a moderate rate performance. Here, we design microporous carbon nanospheres using a novel hybrid monomer that simultaneously involves an organic moiety and an inorganic moiety as the starting unit. The inorganic moiety forms a continuous network, which serves as a 3D scaffold and a nanometer-scale template, then supports the off-collapse of the carbon skeleton and creates a well-developed microporous structure. In addition, the graphite microcrystal structure can be tailored by adjusting the heating treatment temperatures. The electrochemical study demonstrates that the microporous carbon nanospheres show dominant capacitive sodium storage behavior, thus presenting an outstanding rate performance. Even if a very high current density of 10 A g-1 is applied, the hard carbon anode can deliver a large capacity of 127 mAh g-1 with a considerable plateau capacity of 53 mAh g-1, which has rarely been obtained in previous publications. Besides, the carbon anode has a good cycling stability, and the capacity reached 210 mAh g-1 after 1000 cycles with a current density of 1 A g-1, showing no dramatic capacity loss.

15.
Mol Med ; 27(1): 96, 2021 08 28.
Artigo em Inglês | MEDLINE | ID: mdl-34454425

RESUMO

BACKGROUND: Apoptosis of chondrocyte is involved in osteoarthritis (OA) pathogenesis, and mechanical stress plays a key role in this process by activation of Piezo1. However, the negative regulation of signal conduction mediated by mechanical stress is still unclear. Here, we elucidate that the critical role of G protein coupled estrogen receptor (GPER) in the regulation of mechanical stress-mediated signal transduction and chondrocyte apoptosis. METHODS: The gene expression profile was detected by gene chip upon silencing Piezo1. The expression of GPER in cartilage tissue taken from the clinical patients was detected by RT-PCR and Western blot as well as immunohistochemistry, and the correlation between GPER expression and OA was also investigated. The chondrocytes exposed to mechanical stress were treated with estrogen, G-1, G15, GPER-siRNA and YAP (Yes-associated protein)-siRNA. The cell viability of chondrocytes was measured. The expression of polymerized actin and Piezo1 as well as the subcellular localization of YAP was observed under laser confocal microscope. Western blot confirmed the changes of YAP/ Rho GTPase activating protein 29 (ARHGAP29) /RhoA/LIMK /Cofilin pathway. The knee specimens of osteoarthritis model were stained with safranin and green. OARSI score was used to evaluate the joint lesions. The expressions of GPER and YAP were detected by immunochemistry. RESULTS: Expression profiles of Piezo1- silenced chondrocytes showed that GPER expression was significantly upregulated. Moreover, GPER was negatively correlated with cartilage degeneration during OA pathogenesis. In addition, we uncovered that GPER directly targeted YAP and broadly restrained mechanical stress-triggered actin polymerization. Mechanism studies revealed that GPER inhibited mechanical stress-mediated RhoA/LIMK/cofilin pathway, as well as the actin polymerization, by promoting expression of YAP and ARHGAP29, and the YAP nuclear localization, eventually causing the inhibition of Piezo1. YAP was obviously decreased in degenerated cartilage. Silencing YAP caused significantly increased actin polymerization and activation of Piezo1, and an increase of chondrocyte apoptosis. In addition, intra-articular injection of G-1 to OA rat effectively attenuated cartilage degeneration. CONCLUSION: We propose a novel regulatory mechanism underlying mechanical stress-mediated apoptosis of chondrocyte and elucidate the potential application value of GPER as therapy targets for OA.


Assuntos
Apoptose , Condrócitos/metabolismo , Canais Iônicos/genética , Osteoartrite/etiologia , Osteoartrite/metabolismo , Receptores de Estrogênio/metabolismo , Estresse Mecânico , Idoso , Animais , Apoptose/genética , Biomarcadores , Estudos de Casos e Controles , Células Cultivadas , Condrócitos/patologia , Modelos Animais de Doenças , Suscetibilidade a Doenças , Feminino , Citometria de Fluxo , Proteínas Ativadoras de GTPase/metabolismo , Regulação da Expressão Gênica , Inativação Gênica , Humanos , Canais Iônicos/metabolismo , Masculino , Pessoa de Meia-Idade , Osteoartrite/patologia , Ratos , Receptores de Estrogênio/genética , Receptores Acoplados a Proteínas G/metabolismo , Transdução de Sinais , Proteína rhoA de Ligação ao GTP/metabolismo
16.
J Nat Prod ; 84(8): 2265-2271, 2021 08 27.
Artigo em Inglês | MEDLINE | ID: mdl-34355562

RESUMO

Seven highly oxidized steroids, taccachatrones A-G (1-7), together with four known taccalonolides (8-11), were characterized from the rhizomes of Tacca chantrieri. The structures of 1-7 were established on the basis of spectroscopic data analysis, while the absolute configurations were determined by single-crystal X-ray diffraction. Compounds 1-4 may be derived from taccalonolide derivatives by the degradation of three carbon atoms. Compounds 7, 8, 10, and 11 exhibited cytotoxicity to human cancer cell lines, indicating that the presence of a lactone moiety, as well as a double bond between C-22 and C-23, might play key roles in mediating their cytotoxicity.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Dioscoreaceae/química , Esteroides/farmacologia , Antineoplásicos Fitogênicos/isolamento & purificação , Linhagem Celular Tumoral , China , Humanos , Estrutura Molecular , Compostos Fitoquímicos/isolamento & purificação , Compostos Fitoquímicos/farmacologia , Rizoma/química , Esteroides/isolamento & purificação
17.
Bioorg Chem ; 111: 104874, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33887585

RESUMO

Seven previously undescribed trichothecenes, named trichothecrotocins M-S (1-7), along with five known compounds, were isolated from rice cultures of the potato-associated fungus Trichothecium crotocinigenum. Their structures and absolute configurations were determined through spectroscopic methods, single-crystal X-ray diffraction, and quantum chemistry calculations on ECD. Compound 1 possesses a rare 6,11-epoxy moiety in the trichothecene family. Compound 6 exhibited strong cytotoxic activity against MCF-7 cancer cell lines with an IC50 value of 2.34 ± 0.45 µM. It promoted apoptosis induction in MCF-7 cells. Moreover, cell cycle analysis showed cell cycle arrest caused by compound 6 at the G2/M phase which resulted to cell proliferation inhibition and pro-apoptotic activity. Further quantitative real-time PCR (qRT-PCR) analysis confirmed that the G2/M arrest was accompanied by upregulation of p21 and down regulation of cyclins B1 in 6-treated MCF-7 cells.


Assuntos
Antineoplásicos/farmacologia , Hypocreales/química , Solanum tuberosum/química , Tricotecenos/farmacologia , Antineoplásicos/química , Antineoplásicos/metabolismo , Apoptose/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Hypocreales/metabolismo , Células MCF-7 , Simulação de Acoplamento Molecular , Estrutura Molecular , Solanum tuberosum/metabolismo , Relação Estrutura-Atividade , Tricotecenos/química , Tricotecenos/metabolismo
18.
J Asian Nat Prod Res ; 23(4): 348-352, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32174165

RESUMO

Two new tremulane-type sesquiterpenes, irlactin L (1) and irlactin M (2) were isolated from cultures of the fungus Irpex lacteus, together with one known compound, 6-hydroxy-2,6-dimethyloct-7-enoic acid (3). Their structures were elucidated by spectroscopic data analysis. Compounds 1-2 were tested for their cytotoxicities against five human cancer cell lines and for their inhibitory activities against isozymes of 11ß-hydroxysteroid dehydrogenases (11ß-HSD).[Formula: see text].


Assuntos
Polyporales , Sesquiterpenos , Fungos , Estrutura Molecular , Sesquiterpenos/farmacologia
19.
Molecules ; 26(18)2021 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-34577082

RESUMO

In our continuous search for antibacterial agents against Pseudomonas syringae pv. actinidiae (Psa) from kiwi-associated fungi, two pairs of epimeric cytochalasins, zopfiellasins A-D (1-4), were characterized from the fungus Zopfiella sp. The structures were established on the basis of spectroscopic data analysis, while the absolute configurations were determined by single-crystal X-ray diffraction. Compounds 1 and 3 exhibited antibacterial activity against Psa with MIC values of 25 and 50 µg/mL, respectively. This is the first report of anti-Psa activity of cytochalasin derivatives.


Assuntos
Actinidia/microbiologia , Antibacterianos/química , Antibacterianos/farmacologia , Citocalasinas/química , Citocalasinas/farmacologia , Sordariales/química , Antibacterianos/isolamento & purificação , Citocalasinas/isolamento & purificação , Espectroscopia de Ressonância Magnética , Pseudomonas syringae/efeitos dos fármacos , Estereoisomerismo , Difração de Raios X
20.
Entropy (Basel) ; 23(2)2021 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-33672339

RESUMO

A rolling bearing early fault diagnosis method is proposed in this paper, which is derived from a refined composite multi-scale approximate entropy (RCMAE) and improved coyote optimization algorithm based probabilistic neural network (ICOA-PNN) algorithm. Rolling bearing early fault diagnosis is a time-sensitive task, which is significant to ensure the reliability and safety of mechanical fault system. At the same time, the early fault features are masked by strong background noise, which also brings difficulties to fault diagnosis. So, we firstly utilize the composite ensemble intrinsic time-scale decomposition with adaptive noise method (CEITDAN) to decompose the signal at different scales, and then the refined composite multi-scale approximate entropy of the first signal component is calculated to analyze the complexity of describing the vibration signal. Afterwards, in order to obtain higher recognition accuracy, the improved coyote optimization algorithm based probabilistic neural network classifiers is employed for pattern recognition. Finally, the feasibility and effectiveness of this method are verified by rolling bearing early fault diagnosis experiment.

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