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1.
J Ethnopharmacol ; 282: 114615, 2022 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-34509606

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Danshen, the dried rhizome of Salvia miltiorrhiza Bge., is widely used to treat cardio-cerebrovascular diseases in China. However, its role in nourishing blood, which has been detailed in historical literature for thousands of years, is perpetually disputed in the academic field. Moreover, there is no systematic research on Danshen in treating anemia. This research aimed to investigate the effects and mechanisms of Danshen on anemia in a zebrafish model based on the results of a network pharmacology study. MATERIALS AND METHODS: The network pharmacology study was based on the screening of chemical components and related targets from TCMSP and SwissADME database. The genes associated with anemia were obtained from DisgeNet database, and the genes with the intersection of Danshen target genes were screened out. The Cytoscape 3.7.2 software package was used to construct the "ingredient-target-pathway" network. The exploration of target interaction by String system and the enrichment analysis by Metascape system, was used to discover the possible anti-anemia action mechanism of Danshen. Then, a zebrafish anemia model was induced by vinorelbine followed by the administration of aqueous/ethanol extract of Danshen in contrast to SiWu Decoction (SWD), which is generally acknowledged as a positive drug for tonifying blood. Afterward, the red blood cell signal, cardiac output, and blood flow velocity were detected to evaluate their blood-enriching effects. Quantitative real-time polymerase chain reaction (qPCR) was used to analyze the mRNA levels of hematopoietic-related factors, which were predicted in network pharmacology. RESULTS: Compounds and target screening hinted that 115 chemical targets from Danshen were related to anemia, KEGG pathway enrichment results suggested that the mechanism of Danshen in treating anemia was significantly related to the Jak-STAT signaling pathway. Pharmacodynamic results showed that aqueous extract of Danshen (DSAE) and ethanol extract of Danshen (DSEE) markedly enhanced the number of red blood cells, cardiac output, and blood flow velocity. Compared with DSAE, DSEE exerted anti-anemia effects at a lower dose; however, along with higher toxicity. PCR data demonstrated that DSAE and DSEE treatment both upregulated the mRNA expression of erythroid hematopoiesis-related factors in the Epo-JAK-STAT signaling pathway, such as Gata-1, Epo, EpoR, Jak2, STAT3, and STAT5. In general, DSAE exhibited higher activation of this signaling than DSEE. CONCLUSIONS: These results indicated that DSAE and DSEE both possess blood-enriching functions related with their ability to promote Jak-STAT signaling. DSAE exerted lower toxicity and attenuated anemia over a wider dose range than DSEE, which suggests that DSAE may be more suitable for the treatment for anemia. These results presented experimental evidence for the clinical use of Danshen as an intervention for anemia, especially in chemotherapy-induced anemia.

2.
Sheng Wu Gong Cheng Xue Bao ; 37(9): 3005-3019, 2021 Sep 25.
Artigo em Chinês | MEDLINE | ID: mdl-34622613

RESUMO

Formins are widely distributed in eukaryotes such as fungi, plants and animals. They play crucial roles in regulating the polymerization of actin, coordinating the synergistic interactions between actin and microtubules, and determining cell growth and morphology. Unlike formins from fungi and animals, plant formins have been evolved into two plant-specific types. Generally, type Ⅱ formins are believed to regulate the polarized growth of cells, and type Ⅰ formins may regulate the cell expansion and division processes. Recent studies on the function of plant formins suggest it is inappropriate to classify the function of formins purely based on their structures. This review summarizes the domain organization of formins and their corresponding functions, as well as the underpinning mechanisms. Furthermore, the unsolved or unexplored issues along with future perspectives on plant formins are proposed and discussed.


Assuntos
Forminas , Proteínas dos Microfilamentos , Células Vegetais , Desenvolvimento Vegetal , Actinas , Plantas
3.
Inquiry ; 58: 469580211049065, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34647508

RESUMO

To investigate attention deficit hyperactivity disorder (ADHD) core symptoms that impair executive function (EF), emotional state, learning motivation, and the family and parenting environment of children and adolescents with ADHD, both with and without severe difficulties. This will be explored within an online learning environment during the period of COVID-19 pandemic. A total of 183 ADHD children diagnosed using DSM-V criteria were selected and divided into 2 groups high difficulties during online learning (HDOL) and low difficulties during online learning (LDOL) according to the answer of Home Quarantine Investigation of the Pandemic (HQIP). The participants filled out a set of questionnaires to assess their emotional state and learning motivation, and their parents also filled out the questionnaires about ADHD core symptoms, EF, and family and parenting environment. Compared with ADHD children in the LDOL group, the children in the HDOL group had significant symptoms of inattention, hyperactivity, oppositional defiant, behavioral and emotional problems according to the Swanson, Nolan, and Pelham Rating Scale (SNAP). They also had more severely impaired EF according to the Behavior Rating Inventory of Executive Function (BRIEF), more difficulties and disturbances in the family by the Chinese version of Family Environment Scale (FES-CV), and lower parenting efficacy and satisfaction by Parenting Sense of Competence (PSOC). With regard to the self-rating questionnaires of children and adolescents, the HDOL group reported lower learning motivation according to the Students Learning Motivation Scale (SLMS). By Screening for Child Anxiety-Related Emotional Disorders and Depression Self-Rating Scale for Children (DSRSC), those in HDOL presented more negative emotions. The HDOL group spent significantly more time on both video games and social software per day and significantly less time on multiple activities per week, when compared to those in the LDOL group. This study demonstrated that ADHD children and adolescents with HDOL had more inattention-related behaviors, more severe emotional problems and EF impairment, weaker learning motivation, and poorer family and parenting environment. Meanwhile, digital media use should be supervised and appropriate extracurricular activities should be encouraged by parents and schools.

4.
Bioorg Chem ; 116: 105387, 2021 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-34628225

RESUMO

Alzheimer's disease (AD) is a prevalent neurodegenerative disorder that has multiple causes. Therefore, multiple-target-directed ligands (MTDLs), which act on multiple targets, have been developed as a novel strategy for AD therapy. In this study, novel drug candidates were designed and synthesized by the covalent linkings of tacrine, a previously used anti-AD acetylcholinesterase (AChE) inhibitor, and dipicolylamine, an ß-amyloid (Aß) aggregation inhibitor. Most tacrine-dipicolylamine dimers potently inhibited AChE and Aß1-42 aggregation in vitro, and 13a exhibited nanomolar level inhibition. Molecular docking analysis suggested that 13a could interact with the catalytic active sites and the peripheral anion site of AChE, and bind to Aß1-42 pentamers. Moreover, 13a effectively attenuated Aß1-42 oligomers-induced cognitive dysfunction in mice by activating the cAMP-response element binding protein/brain-derived neurotrophic factor signaling pathway, decreasing tau phosphorylation, preventing synaptic toxicity, and inhibiting neuroinflammation. The safety profile of 13a in mice was demonstrated by acute toxicity experiments. All these results suggested that novel tacrine-dipicolylamine dimers, especially 13a, have multi-target neuroprotective and cognitive-enhancing potentials, and therefore might be developed as MTDLs to combat AD.

5.
BMC Bioinformatics ; 22(1): 418, 2021 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-34479477

RESUMO

BACKGROUND: Prediction of the drug-target interaction (DTI) is a critical step in the drug repurposing process, which can effectively reduce the following workload for experimental verification of potential drugs' properties. In recent studies, many machine-learning-based methods have been proposed to discover unknown interactions between drugs and protein targets. A recent trend is to use graph-based machine learning, e.g., graph embedding to extract features from drug-target networks and then predict new drug-target interactions. However, most of the graph embedding methods are not specifically designed for DTI predictions; thus, it is difficult for these methods to fully utilize the heterogeneous information of drugs and targets (e.g., the respective vertex features of drugs and targets and path-based interactive features between drugs and targets). RESULTS: We propose a DTI prediction method DTI-HeNE (DTI based on Heterogeneous Network Embedding), which is specifically designed to cope with the bipartite DTI relations for generating high-quality embeddings of drug-target pairs. This method splits a heterogeneous DTI network into a bipartite DTI network, multiple drug homogeneous networks and target homogeneous networks, and extracts features from these sub-networks separately to better utilize the characteristics of bipartite DTI relations as well as the auxiliary similarity information related to drugs and targets. The features extracted from each sub-network are integrated using pathway information between these sub-networks to acquire new features, i.e., embedding vectors of drug-target pairs. Finally, these features are fed into a random forest (RF) model to predict novel DTIs. CONCLUSIONS: Our experimental results show that, the proposed DTI network embedding method can learn higher-quality features of heterogeneous drug-target interaction networks for novel DTIs discovery.


Assuntos
Desenvolvimento de Medicamentos , Preparações Farmacêuticas , Interações Medicamentosas , Reposicionamento de Medicamentos , Aprendizado de Máquina
6.
Artigo em Inglês | MEDLINE | ID: mdl-34564804

RESUMO

A Gram-negative, rod-shaped, motile and strictly aerobic bacterium, designated NBU1469T, was isolated from marine sediment sampled on Meishan Island located in the East China Sea. Strain NBU1469T grew optimally at temperature of 40 °C, NaCl concentration of 2.0% (w/v) and pH 7.5. Catalase and oxidase activities, H2S production, nitrate reduction and hydrolysis of Tween 20 were positive. Indole, methyl red reaction, urease, hydrolysis of gelatin, starch, casein, Tweens 40, 60 and 80 were negative. The major cellular fatty acids were C16:0, C19:0 cyclo ω8c and summed feature 8 (C18:1 ω7c and/or C18:1 ω6c). The only respiratory quinone was ubiquinone-10 (Q-10). The major polar lipids were phosphatidylglycerol, two unidentified amino-phospholipids and two unidentified phospholipids. Comparative analysis of the 16S rRNA gene sequence showed highest similarities to the species with validated name Nisaea nitritireducens DR41_18T (98.1%) and Nisaea denitrificans DR41_21T (97.6%). Phylogenetic analyses indicated that strain NBU1469T formed a distinct lineage with strains Nisaea nitritireducens DR41_18T and Nisaea denitrificans DR41_21T within the genus Nisaea. The average nucleotide identity and digital DNA-DNA hybridization values between strain NBU1469T and related species of genus Nisaea were well below the threshold limit for prokaryotic species delineation. The DNA G + C content was 63.6%. Based on its phenotypic, chemotaxonomic and genotypic data, strain NBU1469T is considered to be a representative of a novel species in the genus Nisaea, for which the name Nisaea sediminum sp. nov. is proposed. The type strain is NBU1469T (=KCTC 82224 T =MCCC 1K04763T).

7.
Nat Prod Res ; : 1-8, 2021 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-34569875

RESUMO

Four new cembrane diterpenes, 1,13-di-epi-13-acetoxy launine P (1), 13-oxo-thunbergol (2), isocrassumol B (3) and 7α, 8α-sarcophine (4), together with two known launine P (5) and sarcophytonin B (6), were isolated from the extract of the South China Sea soft coral Sarcophyton trocheliophorum. The structures were elucidated by spectroscopic analysis, ECD analysis and comparison with literature data. All compounds were tested for their antimicrobial activity and antiviral activity. Compounds 1, 2 and 5 were found to exhibit weak antibacterial activity, while 6 showed strong inhibition activity against Staphylococcus aureus and Bacillus subtilis (MIC<0.5 µg/mL). Compounds 2 showed moderate inhibitory effect against influenza A viruses H1N1 with IC50 of 17.8 µM.

8.
Mar Drugs ; 19(9)2021 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-34564188

RESUMO

In nature, secondary metabolites have been proven to be the essential communication media between co-occurring microorganisms and to influence their relationship with each other. In this study, we conducted a metabolomics survey of the secondary metabolites of an artificial co-culture related to a hydrothermal vent fungal-bacterial community comprising Aspergillus sclerotiorum and Streptomyces and their reciprocal relationship. The fungal strain was found to increase the secretion of notoamides and the compound cyclo(Pro-Trp) produced by the actinomycetes strain was discovered to be the responsible molecule. This led to the hypothesis that the fungi transformed cyclo(Pro-Trp) synthesized by the actinomycetes as the biosynthetic precursors of notoamides in the chemical communication. Further analysis showed Streptomyces sp. WU20 was efficient in transforming amino acids into cyclo(Pro-Trp) and adding tryptophan as well as proline into the chemical communication enhanced the induction of the notoamide accumulation. Thus, we propose that the microbial transformation during the synthetic metabolically-mediated chemical communication might be a promising means of speeding up the discovery of novel bioactive molecules. The objective of this research was to clarify the mechanism of microbial transformation for the chemical communication. Besides, this research also highlights the utility of mass spectrometry-based metabolomics as an effective tool in the direct biochemical analysis of community metabolites.

9.
J Phys Chem Lett ; : 8598-8604, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34468154

RESUMO

Charge and electronic energy transfer form the basis of many natural and artificial energy transduction systems. The energy landscapes that drive these transfer processes are often constructed from enthalpy changes. In contrast, the entropic effect, although occasionally invoked to explain some excited-state dynamics, has rarely been used to actively control charge/energy flow. Here we derive a generic formula describing how entropy can quantitatively gate the thermally activated delayed emission lifetime in semiconductor nanocrystal-molecular triplet acceptor complexes and experimentally verify the model using highly emissive, quantum-confined CsPbBr3 nanocrystals surface-functionalized with multiple phenanthrene triplet acceptors. Triplet energy transfer from photoexcited CsPbBr3 nanocrystals to phenanthrene is followed by thermally activated repopulation of nanocrystal excitons, leading to delayed nanocrystal emission. The lifetime of delayed emission increases with the phenanthrene/nanocrystal ratio, due to lowering of the free energy of the acceptor state by entropic gain. This study points toward a direction of using entropy to artificially design donor-acceptor light-emitting materials with predetermined excited-state lifetimes.

10.
Chirality ; 33(10): 731-744, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34472145

RESUMO

Due to the similar physicochemical properties, the discrimination of chiral isomers faces huge challenges in drug production and biochemical analysis. Herein, the bovine serum albumin-coated titanium dioxide (bovine serum albumin [BSA]/TiO2 ) was modified as a novel electrochemical interface for efficient, simple, and enantioselective discrimination of aspartic acid enantiomers (D/L-Asp) based on the electrochemical impedance spectroscopy (EIS). Utilizing the structural characteristics of large cavity and high specific surface area, TiO2 material provided sufficient space for adequate loading of BSA. The BSA/TiO2 electrochemical interface was successfully fabricated to support abundant chiral recognition sites. The enantioselective discrimination of D/L-Asp was achieved on the interface with a good linear relationship against the impedance difference in the concentration range from 1 to 1000 nM with the detection limit of 0.37 nM for L-Asp and 0.94 nM for D-Asp, reaching the identification coefficient (Ic = KL /KD ) of 1.85. The proposed interface is easy to form with a stable formation of BSA in TiO2 microporous architecture, which maintained the desired stability and reproducibility. For the unknown racemic solution, Ic levels of different enantio-ratios of D/L-Asp were effectively obtained to evaluate the chiral percentage of racemic sample. The possible mechanism of chiral recognition by density function theory (DFT) was confirmed with a stronger adsorption to L-Asp in accordance with our experiment results, reinforcing the validity of our presented interface. The BSA/TiO2 electrochemical interface with robust enantioselective discrimination of D/L-Asp has great potential for the practical application in pharmaceutical surveillance and food security.

11.
Fish Physiol Biochem ; 2021 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-34581919

RESUMO

Memory drove a critical process of feeding habit transformation in Chinese perch when they re-trained to eat dead prey fish. To investigate the regulatory mechanism of cAMP-response element-binding protein (CREB) signaling pathway on the memory of Chinese perch during feeding habit transformation, the phosphorylation levels of upstream signal proteins of CREB between the control group (trained once) and the experimental group (trained twice) were measured. The results illustrated that the re-training was correlated to phosphorylation of extracellular regulated protein kinase (ERK1/2) and calcium/calmodulin-dependent protein kinase II (CaMKII), and dephosphorylation of protein kinase A (PKA) of Chinese perch. Inhibition of ERK1/2-CREB pathway decreased the mRNA levels of memory-related genes ((fos-related antigen 2 (fra2), CCAAT enhancer-binding protein delta (c/ebpb), immediate-early gene zif268 (zif268), proto-oncogenes c-fos (c-fox) and synaptotagmin-IV (sytIV)) and mRNA levels of appetite-related genes (agouti-related peptide (agrp) and ghrelin), and activation of PP1-CREB pathway increased the phosphorylated levels of CREB, the mRNA levels of memory-related genes (fra2, c/ebpb, zif268, and c-fox), and the mRNA levels of appetite-related genes (pro-opiomelanocortin (pomc) and leptin) in primary brain cells of Chinese perch. The memory in Chinese perch feeding habit transformation was associated with the ERK1/2-CREB and PP1-CREB pathways, which could regulate the transcription of memory-related genes and appetite-related genes.

12.
J Transl Med ; 19(1): 404, 2021 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-34565408

RESUMO

BACKGROUND: The molecular profiling of glioblastoma (GBM) based on transcriptomic analysis could provide precise treatment and prognosis. However, current subtyping (classic, mesenchymal, neural, proneural) is time-consuming and cost-intensive hindering its clinical application. A simple and efficient method for classification was imperative. METHODS: In this study, to simplify GBM subtyping more efficiently, we applied a random forest algorithm to conduct 26 genes as a cluster featured with hub genes, OLIG2 and CD276. Functional enrichment analysis and Protein-protein interaction were performed using the genes in this gene cluster. The classification efficiency of the gene cluster was validated by WGCNA and LASSO algorithms, and tested in GSE84010 and Gravandeel's GBM datasets. RESULTS: The gene cluster (n = 26) could distinguish mesenchymal and proneural excellently (AUC = 0.92), which could be validated by multiple algorithms (WGCNA, LASSO) and datasets (GSE84010 and Gravandeel's GBM dataset). The gene cluster could be functionally enriched in DNA elements and T cell associated pathways. Additionally, five genes in the signature could predict the prognosis well (p = 0.0051 for training cohort, p = 0.065 for test cohort). CONCLUSIONS: Our study proved the accuracy and efficiency of random forest classifier for GBM subtyping, which could provide a convenient and efficient method for subtyping Proneural and Mesenchymal GBM.

13.
J Agric Food Chem ; 69(34): 9764-9777, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34404210

RESUMO

The marine natural product fucoxanthin has been reported previously to produce anti-Alzheimer's disease (AD) neuroprotective effects in vitro and in vivo. Fucoxanthin was also demonstrated to be safe in preclinical and small population clinical studies, but the low bioavailability of fucoxanthin in the central nervous system (CNS) has limited its clinical applications. To overcome this, poly lactic-co-glycolic acid-block-polyethylene glycol loaded fucoxanthin (PLGA-PEG-Fuc) nanoparticles with diameter at around 200 nm and negative charge were synthesized and suggested to penetrate into the CNS. Loaded fucoxanthin could be liberated from PLGA-PEG nanoparticles by sustained released in the physiological environment. PLGA-PEG-Fuc nanoparticles were shown to significantly inhibit the formation of Aß fibrils and oligomers. Moreover, these nanoparticles were taken up by both neurons and microglia, leading to the reduction of Aß oligomers-induced neurotoxicity in vitro. Most importantly, intravenous injection of PLGA-PEG-Fuc nanoparticles prevented cognitive impairments in Aß oligomers-induced AD mice with greater efficacy than free fucoxanthin, possibly via acting on Nrf2 and NF-κB signaling pathways. These results altogether suggest that PLGA-PEG nanoparticles can enhance the bioavailability of fucoxanthin and potentiate its efficacy for the treatment of AD, thus potentially enabling its future use for AD therapy.


Assuntos
Nanopartículas , Feófitas , Peptídeos beta-Amiloides , Animais , Carotenoides , Portadores de Fármacos , Camundongos , Polietilenoglicóis , Xantofilas
14.
Mar Drugs ; 19(7)2021 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-34356822

RESUMO

Metabolomics can be used to study complex mixtures of natural products, or secondary metabolites, for many different purposes. One productive application of metabolomics that has emerged in recent years is the guiding direction for isolating molecules with structural novelty through analysis of untargeted LC-MS/MS data. The metabolomics-driven investigation and bioassay-guided fractionation of a biomass assemblage from the South China Sea dominated by a marine filamentous cyanobacteria, cf. Neolyngbya sp., has led to the discovery of a natural product in this study, wenchangamide A (1). Wenchangamide A was found to concentration-dependently cause fast-onset apoptosis in HCT116 human colon cancer cells in vitro (24 h IC50 = 38 µM). Untargeted metabolomics, by way of MS/MS molecular networking, was used further to generate a structural proposal for a new natural product analogue of 1, here coined wenchangamide B, which was present in the organic extract and bioactive sub-fractions of the biomass examined. The wenchangamides are of interest for anticancer drug discovery, and the characterization of these molecules will facilitate the future discovery of related natural products and development of synthetic analogues.

15.
J Comp Physiol B ; 191(5): 881-894, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34373935

RESUMO

It is well known that carnivorous fish cannot use plant-proteins efficiently. They affect lipid metabolism of fish and cause serious problems to fish health. The reasons for this deficiency of fish metabolism are not known well. Chinese perch, a carnivorous fish, can accept artificial diet after domestication and is also considered as a novel model of fish for nutrition studies. Therefore, the aim of this study was to explore the effect of fish meal replacement by low- or high-rapeseed meal on lipid and glucose metabolism of Chinese perch. Three experimental diets were formulated with 0, 10%, and 30% rapeseed meal, named as Control, RSL, and RSH groups, respectively. After 8-weeks of the feeding trial, the inhibition of growth and fat deposition were observed in Chinese perch fed with rapeseed meal diets compared to the control group. Fish fed with RSL diets showed decreased food intake, serum low density lipoprotein (LDL), phosphorylated Grb10 (P < 0.05), inhibited fatty acid (FA) transport (lipoprotein lipase (LPL)), and glycerol synthesis (phosphoenol pyruvate carboxykinase (PEPCK)) in the liver. In addition, fish fed with RSL diets were also inhibited FA synthesis (fatty acid synthase (FAS), sterol regulatory element binding protein 1 (SREBP1), and Acetyl-CoA carboxylase (ACC1)), lipid uptake (hepatic lipase (HL)), ß-oxidation (carnitine palmitoyltransferase I (CPT1)), and glycerol synthesis (PEPCK) in the visceral adipose tissue. Fish fed with RSH diets showed phosphorylated AMPK, inhibited FA synthesis (SREBP1, ACC1, and FAS), while enhanced lipolysis (hormone-sensitive lipase (HSL)), and then reduced Acetyl-CoA pool. In turn, ß-oxidation (peroxisome proliferator-activated receptor-a (PPARα) and CPT1) was inhibited, while glycolysis (glucose-6-phosphatase (G6PD) and pyruvate carboxylase (PC)) were enhanced, consequently the lipid accumulation was decreased in the liver. Fish were also inhibited lipid uptake (LPL), that caused inhibiting of FA synthesis (SREBP1), ß-oxidation (CPT1), glycerol synthesis (PEPCK), and in turn improved lipolysis (HSL) in the visceral adipose tissue. Our study suggested that both RSL and RSH diets decreased lipid accumulation in Chinese perch; however, the mechanism of lipid metabolism was different. Fish accepted less diet in RSL group, which inhibited lipid metabolism in the liver and in the visceral adipose tissues, while fish in RSH group activated AMPK pathway, inhibited FA synthesis, and enhanced lipolysis, which reduced Acetyl-CoA pool in the liver. Subsequently, lipid uptake and metabolism were inhibited in the visceral adipose tissue of RSH fish.

16.
Fitoterapia ; 154: 105004, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34339802

RESUMO

Chemical investigation for the secondary metabolite of marine-derived fungus Aspergillus sp. LS57 resulted in the isolation of one new chromone named aspergilluone A (1) containing a chromone skeleton fused with an unusual hydrogenation cyclopentanoid ring, along with three known compounds 2-4. The structure of 1 was elucidated by 1D and 2D nuclear magnetic resonance (NMR) spectroscopic and mass spectrometric analyses. Its absolute configuration was established by combining NMR quantum chemical calculations and comparison between the experimental and calculated circular dichroism (CD) curves. Additionally, the antibacterial assay of compound 1 was performed. As a result, compound 1 showed in vitro anti-Mycobacterium tuberculosis with MIC value of 32 µg/mL, together with moderate antibacterial activity against Staphylococcus aureus (MIC values = 64 µg/mL), and exhibited feeble activity against gram-positive Bacillus subtilis and gram-negative pathogen Escherichia coli (both MICs = 128 µg/mL).


Assuntos
Antibacterianos/farmacologia , Aspergillus/química , Cromonas/farmacologia , Poríferos/microbiologia , Animais , Antibacterianos/isolamento & purificação , China , Cromonas/isolamento & purificação , Testes de Sensibilidade Microbiana , Estrutura Molecular
17.
Mar Drugs ; 19(6)2021 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-34198505

RESUMO

A chemical study on the extracts of soft coral Lemnalia bournei resulted in the isolation and identification of six new bicyclic diterpene glycosides including three new lemnaboursides E-G (1-3), and three new lemnadiolboursides A-C (4-6), along with three known lemnaboursides (7-9). Their structures were elucidated by detailed spectroscopic analysis, ECD analysis, chemical methods, and comparison with the literature data. Lemnadiolboursides A-C (4-6) contained a lemnal-1(10)-ene-7,12-diol moiety compared with the lemnaboursides. All these compounds were evaluated for antibacterial activity; cell growth inhibition of A549, Hela, HepG2, and CCRF-CEM cancer cell lines; and inhibition of LPS-induced NO production in RAW264.7 macrophages. The results indicated that compounds 1, 2, and 4-6 exhibited antibacterial activity against Staphylococcus aureus and Bacillus subtilis (MIC 4-16 µg/mL); compounds 1-9 displayed low cytotoxicity on the CCRF-CEM cell lines (IC50 10.44-27.40 µM); and compounds 1, 2, and 5 showed weak inhibition against LPS-induced NO production (IC50 21.56-28.06 µM).

18.
Rev Sci Instrum ; 92(5): 054501, 2021 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-34243339

RESUMO

The Taiji program plans to utilize the laser interferometer to measure the movement at the picometer level between free-floating test masses. As the phase readout equipment, the phasemeter needs to obtain the beat note with an accuracy of µrad/Hz. The main source of noise in the phasemeter is the analog frontend of the analog to digital converter. A self-designed phasemeter prototype with a low-noise analog frontend, which includes the theme of the pilot tone correction, has been developed and tested for the Taiji program in this Note. The experimental results show that the performance of the developed phasemeter can satisfy the Taiji sensitivity requirement in the whole frequency range. The sensitivity of the board can reach 0.5 µrad/Hz in the frequency range of 0.1-1 Hz. Therefore, the prototype gives us a good model for the fully functional Taiji phasemeter.

19.
Artigo em Inglês | MEDLINE | ID: mdl-34319070

RESUMO

The traditional thermoelectric material GeTe has drawn much attention recently because of the reported high thermoelectric performance of the rhombohedral phase in low-temperature ranges, where the split L and Σ band can be reconverged to have a small energy offset and thus high density of state effective mass according to the rhombohedral angle. In addition, In doping in GeTe is also reported to enhance the density of effective mass and therefore increase the Seebeck coefficient because of the induced resonant levels. In this work, In and Pb are doped in GeTe, and In doping leads to an increase in the rhombohedral angle and thus enhanced density of state effective mass in addition to the resonant effect. However, the improved Seebeck coefficient result from In doping is compensated for by a sharp reduction of Hall mobility, leading to no significant enhancement of electronic performance in the rhombohedral phase. By further Pb/Ge doping in the matrix Ge0.95In0.05Te for the optimization of carrier concentration and reduction of lattice thermal conductivity (as low as 0.7 W/mK), a zT as high as ∼1.2 at 550 K and average zT of ∼0.75 between 300 and 550 K are realized in this work, demonstrating GeTe as a promising candidate for near-room-temperature application.

20.
Mol Omics ; 17(5): 790-795, 2021 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-34318850

RESUMO

Adipogenesis and osteoblastogenesis (adipo-osteoblastogenesis) are closely related processes involving with the phosphorylation of numerous cytoplasmic proteins and key transcription factors. Despite the recognition of the importance of protein phosphorylation in adipo-osteoblastocyte biology, relatively little is known about the specific kinases for adipo-osteoblastogenesis. Here, we constructed the comprehensive gene transcriptional landscapes of kinases at 3, 5, and 7 days during adipo-osteoblastogenesis from human bone marrow mesenchymal stem cells (hMSCs). We identified forty-four and eight significant DEGs (differentially expressed genes) separately for adipo-osteoblastogenesis. Five significant DEGs, namely CAMK2A, NEK10, PAK3, PRKG2, and PTK2B, were simultaneously shared by adipo-osteoblastogenic anecdotes. Using a lentivirus system, we confirmed that PTK2B (non-receptor protein tyrosine kinase 2 beta) simultaneously inhibited adipo-osteoblastogenesis through RNAi assays, and PRKG2 (protein kinase cGMP-dependent 2) facilitated adipogenesis and weakened osteoblastogenesis. The only certainty was that the identified candidate significant DEGs encoding kinases responsible for protein phosphorylation, especially PTK2B and PRKG2, were the potential molecular switches of cell fate determination for hMSCs. This study would provide novel study targets for hMSC differentiation and potential clues for the therapy of the adipo-osteoblastogenic balance-derived disorders.

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