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1.
Small ; 20(6): e2306394, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37775949

RESUMO

Nanoparticles form long-range micropatterns via self-assembly or directed self-assembly with superior mechanical, electrical, optical, magnetic, chemical, and other functional properties for broad applications, such as structural supports, thermal exchangers, optoelectronics, microelectronics, and robotics. The precisely defined particle assembly at the nanoscale with simultaneously scalable patterning at the microscale is indispensable for enabling functionality and improving the performance of devices. This article provides a comprehensive review of nanoparticle assembly formed primarily via the balance of forces at the nanoscale (e.g., van der Waals, colloidal, capillary, convection, and chemical forces) and nanoparticle-template interactions (e.g., physical confinement, chemical functionalization, additive layer-upon-layer). The review commences with a general overview of nanoparticle self-assembly, with the state-of-the-art literature review and motivation. It subsequently reviews the recent progress in nanoparticle assembly without the presence of surface templates. Manufacturing techniques for surface template fabrication and their influence on nanoparticle assembly efficiency and effectiveness are then explored. The primary focus is the spatial organization and orientational preference of nanoparticles on non-templated and pre-templated surfaces in a controlled manner. Moreover, the article discusses broad applications of micropatterned surfaces, encompassing various fields. Finally, the review concludes with a summary of manufacturing methods, their limitations, and future trends in nanoparticle assembly.

2.
Molecules ; 29(2)2024 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-38257210

RESUMO

MASM, a structurally modified derivative of matrine, exhibits superior efficacy in reducing inflammation and liver injury in rats when compared to matrine. This study aims to investigate the pharmacokinetic profile and acute toxicity of MASM. Pharmacokinetic results revealed that MASM exhibited rapid absorption, with a Tmax ranging from 0.21 ± 0.04 h to 1.31 ± 0.53 h, and was eliminated slowly, with a t1/2 of approximately 10 h regardless of the route of administration (intravenous, intraperitoneal, or intragastric). The absolute intragastric bioavailability of MASM in rats was determined to be 44.50%, which was significantly higher than that of matrine (18.5%). MASM was detected in all rat tissues including the brain, and through the utilization of stable isotope-labeled compounds and standard references, ten metabolites of MASM, namely sophocarpine, oxysophocarpine, and oxymatrine, were tentatively identified. The LD50 of MASM in mice was determined to be 94.25 mg/kg, surpassing that of matrine (83.21 mg/kg) based on acute toxicity results. Histopathological and biochemical analysis indicated no significant alterations in the primary organs of the low- to medium-dosage groups of MASM. These findings provide valuable insights into the efficacy and toxicity profile of MASM.


Assuntos
Antracenos , Matrinas , Tionas , Camundongos , Ratos , Animais , Radioisótopos de Carbono , Distribuição Tecidual
3.
Small ; 19(50): e2302718, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37501325

RESUMO

Lithium-ion batteries (LIBs) have significantly impacted the daily lives, finding broad applications in various industries such as consumer electronics, electric vehicles, medical devices, aerospace, and power tools. However, they still face issues (i.e., safety due to dendrite propagation, manufacturing cost, random porosities, and basic & planar geometries) that hinder their widespread applications as the demand for LIBs rapidly increases in all sectors due to their high energy and power density values compared to other batteries. Additive manufacturing (AM) is a promising technique for creating precise and programmable structures in energy storage devices. This review first summarizes light, filament, powder, and jetting-based 3D printing methods with the status on current trends and limitations for each AM technology. The paper also delves into 3D printing-enabled electrodes (both anodes and cathodes) and solid-state electrolytes for LIBs, emphasizing the current state-of-the-art materials, manufacturing methods, and properties/performance. Additionally, the current challenges in the AM for electrochemical energy storage (EES) applications, including limited materials, low processing precision, codesign/comanufacturing concepts for complete battery printing, machine learning (ML)/artificial intelligence (AI) for processing optimization and data analysis, environmental risks, and the potential of 4D printing in advanced battery applications, are also presented.

4.
Bioorg Chem ; 135: 106500, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37003134

RESUMO

Blocking the interaction between Ras and Son of Sevenless homolog 1 (SOS1) has been an attractive therapeutic strategy for treating cancers involving oncogenic Ras mutations. K-Ras mutation is the most common in Ras-driven cancers, accounting for 86%, with N-Ras mutation and H-Ras mutation accounting for 11% and 3%, respectively. Here, we report the design and synthesis of a series of hydrocarbon-stapled peptides to mimic the alpha-helix of SOS1 as pan-Ras inhibitors. Among these stapled peptides, SSOSH-5 was identified to maintain a well-constrained alpha-helical structure and bind to H-Ras with high affinity. SSOSH-5 was furthermore validated to bind with Ras similarly to the parent linear peptide through structural modeling analysis. This optimized stapled peptide was proven to be capable of effectively inhibiting the proliferation of pan-Ras-mutated cancer cells and inducing apoptosis in a dose-dependent manner by modulating downstream kinase signaling. Of note, SSOSH-5 exhibited a high capability of crossing cell membranes and strong proteolytic resistance. We demonstrated that the peptide stapling strategy is a feasible approach for developing peptide-based pan-Ras inhibitors. Furthermore, we expect that SSOSH-5 can be further characterized and optimized for the treatment of Ras-driven cancers.


Assuntos
Antineoplásicos , Neoplasias , Humanos , Proteína SOS1/química , Proteína SOS1/genética , Proteína SOS1/metabolismo , Peptídeos/farmacologia , Transdução de Sinais , Mutação , Antineoplásicos/farmacologia
5.
Phytother Res ; 37(3): 809-819, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36447385

RESUMO

Cancer cachexia is a metabolic syndrome that is characterized by progressive loss of skeletal muscle mass, and effective therapeutics have yet to be developed. Saikosaponin D (SSD), a major bioactive component of Radix Bupleuri, exhibits antiinflammatory, anti-tumor, anti-oxidant, anti-viral, and hepatoprotective effects. In this study, we demonstrated that SSD is a promising agent for the treatment of cancer cachexia. SSD could alleviate TCM-induced myotube atrophy and inhibit the expression of E3 ubiquitin ligases muscle RING-finger containing protein-1 (MuRF1) and muscle atrophy Fbox protein (Atrogin-1/MAFbx) in vitro. Moreover, SSD suppressed the progression of cancer cachexia, with significant improvements in the loss of body weight, gastrocnemius muscle, and tibialis anterior muscle mass in vivo. Mechanism investigations demonstrated that SSD could directly bind to STAT3 and specifically inhibit its phosphorylation as well as its transcriptional activity. Overexpression of STAT3 partially abolished the inhibitory effect of SSD on myotube atrophy, indicating that the therapeutic effect of SSD was attributed to STAT3 inhibition. These findings provide novel strategies for treatment of cancer cachexia by targeting STAT3, and SSD may be a promising drug candidate for cancer cachexia.


Assuntos
Caquexia , Neoplasias , Humanos , Caquexia/tratamento farmacológico , Caquexia/metabolismo , Caquexia/patologia , Neoplasias/patologia , Músculo Esquelético , Atrofia Muscular/tratamento farmacológico , Fator de Transcrição STAT3/metabolismo
6.
Mol Biol Evol ; 38(11): 4867-4883, 2021 10 27.
Artigo em Inglês | MEDLINE | ID: mdl-34320652

RESUMO

True sea snakes (Hydrophiini) are among the last and most successful clades of vertebrates that show secondary marine adaptation, exhibiting diverse phenotypic traits and lethal venom systems. To better understand their evolution, we generated the first chromosome-level genomes of two representative Hydrophiini snakes, Hydrophis cyanocinctus and H. curtus. Through comparative genomics we identified a great expansion of the underwater olfaction-related V2R gene family, consisting of more than 1,000 copies in both snakes. A series of chromosome rearrangements and genomic structural variations were recognized, including large inversions longer than 30 megabase (Mb) on sex chromosomes which potentially affect key functional genes associated with differentiated phenotypes between the two species. By integrating multiomics we found a significant loss of the major weapon for elapid predation, three-finger toxin genes, which displayed a dosage effect in H. curtus. These genetic changes may imply mechanisms that drove the divergent evolution of adaptive traits including prey preferences between the two closely related snakes. Our reference-quality sea snake genomes also enrich the repositories for addressing important issues on the evolution of marine tetrapods, and provide a resource for discovering marine-derived biological products.


Assuntos
Hydrophiidae , Animais , Venenos Elapídicos/genética , Evolução Molecular , Genoma , Hydrophiidae/genética , Fenótipo
7.
Hereditas ; 159(1): 27, 2022 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-35739592

RESUMO

BACKGROUND: Sepsis is a life-threatening multi-organ dysfunction caused by the dysregulated host response to infection. Sepsis remains a major global concern with high mortality and morbidity, while management of sepsis patients relies heavily on early recognition and rapid stratification. This study aims to identify the crucial genes and biomarkers for sepsis which could guide clinicians to make rapid diagnosis and prognostication. METHODS: Preliminary analysis of multiple global datasets, including 170 samples from patients with sepsis and 110 healthy control samples, revealed common differentially expressed genes (DEGs) in peripheral blood of patients with sepsis. After Gene Oncology (GO) and pathway analysis, the Weighted Gene Correlation Network Analysis (WGCNA) was used to screen for genes most related with clinical diagnosis. Also, the Protein-Protein Interaction Network (PPI Network) was constructed based on the DEGs and the hub genes were found. The results of WGCNA and PPI network were compared and one shared gene was discovered. Then more datasets of 728 experimental samples and 355 control samples were used to prove the diagnostic and prognostic value of this gene. Last, we used real-time PCR to confirm the bioinformatic results. RESULTS: Four hundred forty-four common differentially expressed genes in the blood of sepsis patients from different ethnicities were identified. Fifteen genes most related with clinical diagnosis were found by WGCNA, and 24 hub genes with most node degrees were identified by PPI network. ARG1 turned out to be the unique overlapped gene. Further analysis using more datasets showed that ARG1 was not only sharply up-regulated in sepsis than in healthy controls, but also significantly high-expressed in septic shock than in non-septic shock, significantly high-expressed in severe or lethal sepsis than in uncomplicated sepsis, and significantly high-expressed in non-responders than in responders upon early treatment. These all demonstrate the performance of ARG1 as a key biomarker. Last, the up-regulation of ARG1 in the blood was confirmed experimentally. CONCLUSIONS: We identified crucial genes that may play significant roles in sepsis by WGCNA and PPI network. ARG1 was the only overlapped gene in both results and could be used to make an accurate diagnosis, discriminate the severity and predict the treatment response of sepsis.


Assuntos
Redes Reguladoras de Genes , Sepse , Biomarcadores , Perfilação da Expressão Gênica/métodos , Humanos , Mapas de Interação de Proteínas/genética , Sepse/diagnóstico , Sepse/genética
8.
Phytother Res ; 36(9): 3662-3671, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35766233

RESUMO

Inflammatory bowel disease (IBD) is a non-specific chronic intestinal inflammatory disease, often presenting with abdominal pain, diarrhea, bloody stool, anorexia, and body loss. It is difficult to cure completely and a promising treatment is urgently needed. Natural compounds can offer promising chemical agents for treatment of diseases. Polydatin is a natural ingredient extracted from the dried rhizome of Polygonum cuspidatum, which has anti-inflammatory, anti-tumor, and dementia protection activities. The purpose of this study was to evaluate the therapeutic effect of polydatin on IBD and explore its possible mechanism. We found that polydatin could effectively suppress the differentiation of Th17 cells in vitro, but had no effect on the differentiation of Treg cells. Polydatin significantly alleviated colitis induced by dextran sulfate sodium (DSS) and 2, 4, 6-trinitrobenzenesulfonic acid (TNBS) in mice, and dramatically decreased the proportion of Th17 cells in spleen and mesenteric lymph nodes. Mechanism investigations revealed that polydatin specifically inhibited signal transducer and activator of transcription 3 (STAT3) phosphorylation by directly binding to STAT3, leading to Th17 cell reduction and thereby alleviating colitis. These findings provide novel insights into the anti-colitis effect of polydatin, which may be a promising drug candidate for the treatment of IBD.


Assuntos
Colite , Doenças Inflamatórias Intestinais , Animais , Diferenciação Celular , Colite/induzido quimicamente , Colite/tratamento farmacológico , Colo , Sulfato de Dextrana , Modelos Animais de Doenças , Glucosídeos , Doenças Inflamatórias Intestinais/patologia , Camundongos , Camundongos Endogâmicos C57BL , Fator de Transcrição STAT3/metabolismo , Estilbenos , Linfócitos T Reguladores/metabolismo , Células Th17 , Ácido Trinitrobenzenossulfônico/metabolismo
9.
Small ; 17(45): e2100817, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34176201

RESUMO

3D printing (additive manufacturing (AM)) has enormous potential for rapid tooling and mass production due to its design flexibility and significant reduction of the timeline from design to manufacturing. The current state-of-the-art in 3D printing focuses on material manufacturability and engineering applications. However, there still exists the bottleneck of low printing resolution and processing rates, especially when nanomaterials need tailorable orders at different scales. An interesting phenomenon is the preferential alignment of nanoparticles that enhance material properties. Therefore, this review emphasizes the landscape of nanoparticle alignment in the context of 3D printing. Herein, a brief overview of 3D printing is provided, followed by a comprehensive summary of the 3D printing-enabled nanoparticle alignment in well-established and in-house customized 3D printing mechanisms that can lead to selective deposition and preferential orientation of nanoparticles. Subsequently, it is listed that typical applications that utilized the properties of ordered nanoparticles (e.g., structural composites, heat conductors, chemo-resistive sensors, engineered surfaces, tissue scaffolds, and actuators based on structural and functional property improvement). This review's emphasis is on the particle alignment methodology and the performance of composites incorporating aligned nanoparticles. In the end, significant limitations of current 3D printing techniques are identified together with future perspectives.


Assuntos
Nanopartículas , Nanoestruturas , Impressão Tridimensional , Alicerces Teciduais
10.
Nano Lett ; 20(5): 3199-3206, 2020 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-32233441

RESUMO

Here reported is the layer-by-layer-based advanced manufacturing that yields a simple, novel, and cost-effective technique for generating selective nanoparticle deposition and orientation in the form of well-controlled patterns. The surface roughness of the three-dimensionally printed patterns and the solid-liquid-air contact line, as well as the nanoparticle interactions in dipped suspensions, determine the carbon nanofiber (CNF) alignment, while the presence of triangular grooves supports the pinning of the meniscus, resulting in a configuration consisting of alternating CNF and polymer channels. The polymer/nanoparticle composites show 10 times lower resistance along with the particle alignment direction than the randomly distributed CNF networks and 6 orders of magnitude lower than that along the transverse direction. The unidirectional alignment of the CNF also demonstrates linear piezoresistivity behavior under small strain deformation along with high sensitivity and selectivity toward volatile organic compounds. The reported advanced manufacturing shows broad applications in microelectronics, energy transport, light composites, and multifunctional sensors.

11.
Pharmacol Res ; 158: 104871, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32413482

RESUMO

Skeletal muscle wasting is the most remarkable phenotypic feature of cancer cachexia that increases the risk of morbidity and mortality. Imperatorin (IMP), a main bioactive component of Angelica dahurica Radix, has been reported to possess several pharmacological effects including potential anti-colitis, anti-arthritis and anti-tumor activities. In this work, we demonstrated that IMP is a promising agent for the treatment of muscle wasting in cancer cachexia. IMP (5-20 µM) dose-dependently attenuated TCM-induced C2C12 myotube atrophy and prevented the induction of E3 ubiquitin ligases muscle RING-finger containing protein-1 (MuRF1) and muscle atrophy Fbox protein (Atrogin-1/MAFbx). Moreove, IMP administration significantly improved chief features of cancer cachexia in vivo, with significant prevention of the loss of body weight and deleterious wasting of multiple tissues, including skeletal muscle, fat and kidney and decreased expression of MuRF1 and Atrogin-1 in cachectic muscles. Cellular signaling pathway analysis showed that IMP selectively inhibited the phosphorylation of signal transducer and activator of transcription 3 (STAT3) in vitro and in vivo, and surface plasmon resonance (SPR) affinity experiments further demonstrated IMP bound to STAT3 in a concentration-dependent resonance manner. Molecular docking results revealed that IMP binds to the SH2 domain of STAT3, forming a hydrogen bond interaction with Arg-609, and a Sigma-Pi interaction with Lys-591. Mechanism analysis demonstrated that STAT3 overexpression markedly weakens the improvements of IMP on myotube atrophy and muscle wasting of cancer cachexia, indicating that STAT3 mediated the therapeutic effect of IMP. All these favorable results indicated that IMP is a new potential therapeutic candidate for cancer cachexia.


Assuntos
Caquexia/metabolismo , Furocumarinas/metabolismo , Músculo Esquelético/metabolismo , Neoplasias/metabolismo , Fator de Transcrição STAT3/antagonistas & inibidores , Fator de Transcrição STAT3/metabolismo , Animais , Caquexia/tratamento farmacológico , Caquexia/patologia , Relação Dose-Resposta a Droga , Furocumarinas/farmacologia , Furocumarinas/uso terapêutico , Células HEK293 , Células HeLa , Humanos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Músculo Esquelético/efeitos dos fármacos , Músculo Esquelético/patologia , Neoplasias/tratamento farmacológico , Neoplasias/patologia , Estrutura Secundária de Proteína , Fator de Transcrição STAT3/química
12.
J Nat Prod ; 82(11): 3089-3095, 2019 11 22.
Artigo em Inglês | MEDLINE | ID: mdl-31702148

RESUMO

The Arctic fungus Eutypella sp. D-1, previously found to produce a variety of cytotoxic cyclopropyl-fused and cyclobutyl-fused pimarane diterpenoids when grown in the defined medium, was induced to produce unusual metabolites by growing on solid rice medium. A chemical investigation on the rice medium extract led to the isolation of four new meroterpenoids, eutypellacytosporins A-D (1-4), along with the known biogenetically related compound cytosporin D (5). The structures of the new compounds were elucidated by their detailed spectroscopic analysis and modified Mosher's method. Compounds 1-4 may be formed by the 12,32-ester linkage of two moieties, cytosporin D (5) and decipienolide A or B. All isolated compounds, except 5, showed weak cytotoxicity against DU145, SW1990, Huh7, and PANC-1 cell lines with IC50 values ranging from 4.9 to 17.1 µM.


Assuntos
Terpenos/química , Terpenos/farmacologia , Xylariales/química , Antibacterianos , Antibióticos Antineoplásicos/química , Antibióticos Antineoplásicos/farmacologia , Regiões Árticas , Linhagem Celular Tumoral , Meios de Cultura , Ensaios de Seleção de Medicamentos Antitumorais , Fermentação , Humanos , Testes de Sensibilidade Microbiana , Estrutura Molecular
13.
Pharmacology ; 104(5-6): 235-243, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31357205

RESUMO

BACKGROUNDS: (6aS, 10S, 11aR, 11bR, 11cS)-10-methylaminododecahydro-3a, 7a-diaza-benzo (de) anthracene-8-thione (MASM), a novel derivative of matrine, exhibits better anti-inflammatory activity. This study was designed to evaluate the protective effect of MASM on acute and chronic liver injuries and explore the possible mechanisms. METHODS: Acute and chronic liver injury models were established by the CCl4 intraperitoneal injection and the protective effect of MASM was assessed by biochemical and histological examination. The infiltration of different monocyte subsets into the liver was characterized and analyzed by flow cytometry. The in vitro effect of MASM on liver nonparenchymal cells was evaluated by real-time PCR and transwell chemotaxis assays. RESULTS: Administration of MASM markedly attenuated acute liver injury and liver fibrosis induced by CCl4 injection. Meanwhile, the infiltrations of Gr1hi monocytes in injured livers and induced hepatic expression of monocyte chemoattractant protein-1 (MCP-1) were greatly inhibited. Cellular experiments demonstrated that MASM not only decreased the expression of MCP-1 but also inhibited its chemotactic activity. CONCLUSIONS: This study demonstrates that the protective effect of MASM on liver injury could be contributed to the suppression of Gr1hi monocyte infiltration to the liver and the inhibition of MCP-1 production and activity. These findings provide new insights into the protective role of MASM in liver injury.


Assuntos
Alcaloides/uso terapêutico , Antracenos/farmacologia , Anti-Inflamatórios/uso terapêutico , Doença Hepática Induzida por Substâncias e Drogas/tratamento farmacológico , Cirrose Hepática/tratamento farmacológico , Monócitos/efeitos dos fármacos , Quinolizinas/uso terapêutico , Tionas/farmacologia , Alcaloides/farmacologia , Animais , Antracenos/uso terapêutico , Anti-Inflamatórios/farmacologia , Antígenos Ly/imunologia , Tetracloreto de Carbono , Doença Hepática Induzida por Substâncias e Drogas/imunologia , Doença Hepática Induzida por Substâncias e Drogas/patologia , Quimiocina CCL2/imunologia , Fígado/efeitos dos fármacos , Fígado/imunologia , Fígado/patologia , Cirrose Hepática/imunologia , Cirrose Hepática/patologia , Masculino , Camundongos Endogâmicos C57BL , Monócitos/imunologia , Quinolizinas/farmacologia , Tionas/uso terapêutico , Matrinas
14.
Nano Lett ; 18(10): 6113-6120, 2018 10 10.
Artigo em Inglês | MEDLINE | ID: mdl-30169958

RESUMO

Solid electrolytes are crucial for the development of solid state batteries. Among different types of solid electrolytes, poly(ethylene oxide) (PEO)-based polymer electrolytes have attracted extensive attention owing to their excellent flexibility and easiness for processing. However, their relatively low ionic conductivities and electrochemical instability above 4 V limit their applications in batteries with high energy density. Herein, we prepared poly(vinylidene fluoride) (PVDF) polymer electrolytes with an organic plasticizer, which possesses compatibility with 4 V cathode and high ionic conductivity (1.2 × 10-4 S/cm) at room temperature. We also revealed the importance of plasticizer content to the ionic conductivity. To address weak mechanical strength of the PVDF electrolyte with plasticizer, we introduced palygorskite ((Mg,Al)2Si4O10(OH)) nanowires as a new ceramic filler to form composite solid electrolytes (CPE), which greatly enhances both stiffness and toughness of PVDF-based polymer electrolyte. With 5 wt % of palygorskite nanowires, not only does the elastic modulus of PVDF CPE increase from 9.0 to 96 MPa but also its yield stress is enhanced by 200%. Moreover, numerical modeling uncovers that the strong nanowire-polymer interaction and cross-linking network of nanowires are responsible for such significant enhancement in mechanically robustness. The addition of 5% palygorskite nanowires also enhances transference number of Li+ from 0.21 to 0.54 due to interaction between palygorskite and ClO4- ions. We further demonstrate full cells based on Li(Ni1/3Mn1/3Co1/3)O2 (NMC111) cathode, PVDF/palygorskite CPE, and lithium anode, which can be cycled over 200 times at 0.3 C, with 97% capacity retention. Moreover, the PVDF matrix is much less flammable than PEO electrolytes. Our work illustrates that the PVDF/palygorskite CPE is a promising electrolyte for solid state batteries.

15.
Molecules ; 24(22)2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31731728

RESUMO

Polystyrene (PS) polymers have broad applications in protective packaging for food shipping, containers, lids, bottles, trays, tumblers, disposable cutlery and the making of models. Currently, most PS products, such as foams, are not accepted for recycling due to a low density in the porous structure. This poses a challenge for logistics as well as creating a lack of incentive to invest in high-value products. This study, however, demonstrated the use of a dry-jet wet-spinning technique to manufacture continuous PS fibers enabled by an in-house designed and developed spinning apparatus. The manufactured fibers showed porosity in the shell and the capability to load particles in their core, a structure with high potential use in environmentally relevant applications such as water treatment or CO2 collections. A two-phase liquid-state microstructure was first achieved via a co-axial spinneret. Following coagulation procedures and heat treatment, phase-separation-based selective dissolution successfully generated the porous-shell/particle-core fibers. The pore size and density were controlled by the porogen (i.e., PEG) concentrations and examined using scanning electron microscopy (SEM). Fiber formation dynamics were studied via rheology tests and gelation measurements. The shell components were characterized by tensile tests, thermogravimetric analysis, and differential scanning calorimetry for mechanical durability and thermal stability analyses.


Assuntos
Nanofibras/química , Poliestirenos/química , Varredura Diferencial de Calorimetria , Microscopia Eletrônica de Varredura , Nanofibras/ultraestrutura , Tamanho da Partícula , Porosidade
16.
Angew Chem Int Ed Engl ; 58(17): 5557-5561, 2019 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-30779275

RESUMO

The lithium-sulfur battery is an attractive option for next-generation energy storage owing to its much higher theoretical energy density than state-of-the-art lithium-ion batteries. However, the massive volume changes of the sulfur cathode and the uncontrollable deposition of Li2 S2 /Li2 S significantly deteriorate cycling life and increase voltage polarization. To address these challenges, we develop an ϵ-caprolactam/acetamide based eutectic-solvent electrolyte, which can dissolve all lithium polysulfides and lithium sulfide (Li2 S8 -Li2 S). With this new electrolyte, high specific capacity (1360 mAh g-1 ) and reasonable cycling stability are achieved. Moreover, in contrast to conventional ether electrolyte with a low flash point (ca. 2 °C), such low-cost eutectic-solvent-based electrolyte is difficult to ignite, and thus can dramatically enhance battery safety. This research provides a new approach to improving lithium-sulfur batteries in aspects of both safety and performance.

17.
J Nat Prod ; 81(7): 1553-1560, 2018 07 27.
Artigo em Inglês | MEDLINE | ID: mdl-29949353

RESUMO

Seven new pimarane-type diterpene derivatives, libertellenones O-S (1-5) and eutypellenones A and B (6 and 7), together with two known compounds (8 and 9), were isolated from the culture of Eutypella sp. D-1 obtained from high-latitude soil of the Arctic. Their structures were elucidated from spectroscopic data, as well as experimental and calculated electronic circular dichroism (ECD) analysis. Structurally, compounds 1-5 possess a cyclopropyl-fused pimarane diterpene moiety, whereas compounds 6 and 7 share an unusual cyclobutyl-fused pimarane diterpene skeleton. Compounds 1-9 exhibited cytotoxicities against HeLa, MCF-7, HCT-116, PANC-1, and SW1990 cells, with IC50 values in the range of 0.3 to 29.4 µM. Compounds 6 and 7 could dose-dependently inhibit the activity of NF-κB and exhibited significantly inhibitory effects on nitric oxide production induced by lipopolysaccharide.


Assuntos
Abietanos/isolamento & purificação , Xylariales/química , Abietanos/química , Anti-Inflamatórios não Esteroides/isolamento & purificação , Anti-Inflamatórios não Esteroides/farmacologia , Antineoplásicos/isolamento & purificação , Antineoplásicos/farmacologia , Regiões Árticas , Linhagem Celular Tumoral , Ensaios de Seleção de Medicamentos Antitumorais , Células HEK293 , Células HeLa , Humanos , Estrutura Molecular , Microbiologia do Solo
18.
Mar Drugs ; 16(8)2018 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-30115869

RESUMO

Three new pimarane diterpenes, eutypellenoids A⁻C (1⁻3), together with a known compound, eutypenoid C (4), were isolated from the culture extract of Eutypella sp. D-1 derived from the Arctic region. Compounds 1⁻3 possessed an uncommon tetrahydrofuran-fused pimarane diterpene skeleton. The structures of all compounds were determined by detailed spectroscopic analysis, electronic circular dichroism (ECD) analysis, as well as a comparison with the literature data. Antibacterial, antifungal, and cytotoxic activities of these compounds were evaluated. Compound 2 displayed antibacterial activity against Staphylococcus aureus and Escherichia coli with MIC values of 8 and 8 µg/mL, respectively. Additionally, compound 2 showed antifungal activity against Candidaparapsilosis, Candida albicans, Candida glabrata, and Candida tropicalis with MIC values of 8, 8, 16, and 32 µg/mL, respectively. Furthermore, compound 2 exhibited moderate cytotoxic activity against HCT-116 cell line with IC50 value of 3.7 µM.


Assuntos
Abietanos/química , Diterpenos/química , Xylariales/química , Antibacterianos/química , Antibacterianos/farmacologia , Antifúngicos/química , Antifúngicos/farmacologia , Regiões Árticas , Linhagem Celular Tumoral , Escherichia coli/efeitos dos fármacos , Fungos/efeitos dos fármacos , Furanos/química , Células HCT116 , Humanos , Testes de Sensibilidade Microbiana/métodos , Staphylococcus aureus/efeitos dos fármacos
19.
Acta Pharmacol Sin ; 38(1): 120-132, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27773936

RESUMO

Matrine is an alkaloid extracted from a Chinese herb Sophora flavescens Ait, which has shown chemopreventive potential against various cancers. In this study, we evaluated the anticancer efficacy of a novel derivative of matrine, (6aS, 10S, 11aR, 11bR, 11cS)-10- methylamino-dodecahydro- 3a,7a-diazabenzo (de) (MASM), against human hepatocellular carcinoma (HCC) cells and their corresponding sphere cells in vitro and in vivo. Human HCC cell lines (Hep3B and Huh7) were treated with MASM. Cell proliferation was assessed using CCK8 and colony assays; cell apoptosis and cell cycle distributions were examined with flow cytometry. The expression of cell markers and signaling molecules was detected using Western blot and qRT-PCR analyses. A sphere culture technique was used to enrich cancer stem cells (CSC) in Hep3B and Huh7 cells. The in vivo antitumor efficacy of MASM was evaluated in Huh7 cell xenograft model in BALB/c nude mice, which were administered MASM (10 mg·kg-1·d-1, ig) for 3 weeks. After the treatment was completed, tumor were excised and weighed. A portion of tumor tissue was enzymatically dissociated to obtain a single cell suspension for the spheroid formation assays. MASM (2, 10, 20 µmol/L) dose-dependently inhibited the proliferation of HCC cells, and induced apoptosis, which correlated with a reduction in Bcl-2 expression and an increase in PARP cleavage. MASM also induced cell cycle arrest in G0/G1 phase, which was accompanied by increased p27 and decreased Cyclin D1 expression. Interestingly, MASM (2, 10, and 20 µmol/L) drastically reduced the EpCAM+/CD133+ cell numbers, suppressed the sphere formation, inhibited the expression of stem cell marker genes and promoted the expression of mature hepatocyte markers in the Hep3B and Huh7 spheroids. Additionally, MASM dose-dependently suppressed the PI3K/AKT/mTOR and AKT/GSK3ß/ß-catenin signaling pathways in Hep3B and Huh7 cells. In Huh7 xenograft bearing nude mice, MASM administration significantly inhibited Huh7 xenograft tumor growth and markedly reduced the number of surviving cancer stem-like cells in the tumors. MASM administration also reduced the expression of stem cell markers while increasing the expression of mature hepatocyte markers in the tumor tissues. The novel derivative of matrine, MASM, markedly suppresses HCC tumor growth through multiple mechanisms, and it may be a promising candidate drug for the treatment of hepatocellular carcinoma.


Assuntos
Alcaloides/química , Alcaloides/farmacologia , Carcinoma Hepatocelular/patologia , Proliferação de Células/efeitos dos fármacos , Compostos Heterocíclicos de 4 ou mais Anéis/farmacologia , Neoplasias Hepáticas/patologia , Células-Tronco Neoplásicas/efeitos dos fármacos , Quinolizinas/química , Quinolizinas/farmacologia , Transdução de Sinais/efeitos dos fármacos , Animais , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Contagem de Células , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Diferenciação Celular , Linhagem Celular Tumoral , Ciclina D1/biossíntese , Relação Dose-Resposta a Droga , Molécula de Adesão da Célula Epitelial/metabolismo , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Camundongos , Camundongos Nus , Células-Tronco Neoplásicas/enzimologia , Células-Tronco Neoplásicas/metabolismo , Fosfatidilinositol 3-Quinases , Antígeno Nuclear de Célula em Proliferação/biossíntese , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto , Matrinas
20.
J Infect Dis ; 214(11): 1762-1772, 2016 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-27658692

RESUMO

BACKGROUND: MASM, a novel derivative of matrine, has inhibitory effects on activation of macrophages, dendritic cells, and hepatic stellate cells and binds to ribosomal protein S5 (RPS5). This study was designed to evaluate the effect of MASM on murine-established lethal sepsis and its mechanisms. METHODS: Mouse peritoneal macrophages and RAW264.7 cells that were infected with recombinant lentiviruses encoding shRPS5 were incubated with lipopolysaccharide (LPS) in the absence or presence of MASM in vitro. Endotoxemia induced by LPS injection and sepsis induced by cecal ligation and puncture was followed by MASM treatment. RESULTS: MASM markedly attenuated LPS-induced release and messenger RNA expression of tumor necrosis factor α, interleukin 6, and NO/inducible NO synthase in murine peritoneal macrophages and RAW264.7 cells. Meanwhile, MASM inhibited LPS-induced activation of nuclear factor κB and MAPK pathways. Consistently, RPS5 suppressed LPS-induced inflammatory responses and at least in part mediated the antiinflammatory effect of MASM in vitro. Remarkably, delayed administration of MASM could significantly reduce mortality in mouse sepsis models, which was associated with the reduction in the inflammatory response, the attenuation in multiple organ injury, and the enhanced bacterial clearance. CONCLUSIONS: MASM could be further explored for the treatments of sepsis, especially for administration later after the onset of sepsis.


Assuntos
Alcaloides/administração & dosagem , Fatores Imunológicos/administração & dosagem , Inflamação/tratamento farmacológico , Inflamação/patologia , Quinolizinas/administração & dosagem , Sepse/tratamento farmacológico , Sepse/patologia , Animais , Modelos Animais de Doenças , Lipopolissacarídeos/toxicidade , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Células RAW 264.7/efeitos dos fármacos , Células RAW 264.7/imunologia , Análise de Sobrevida , Matrinas
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