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1.
EMBO J ; 41(2): e107739, 2022 12 17.
Artigo em Inglês | MEDLINE | ID: mdl-34913508

RESUMO

Stimulatory immune receptor NKG2D binds diverse ligands to elicit differential anti-tumor and anti-virus immune responses. Two conflicting degeneracy recognition models based on static crystal structures and in-solution binding affinities have been considered for almost two decades. Whether and how NKG2D recognizes and discriminates diverse ligands still remain unclear. Using live-cell-based single-molecule biomechanical assay, we characterized the in situ binding kinetics of NKG2D interacting with different ligands in the absence or presence of mechanical force. We found that mechanical force application selectively prolonged NKG2D interaction lifetimes with the ligands MICA and MICB, but not with ULBPs, and that force-strengthened binding is much more pronounced for MICA than for other ligands. We also integrated steered molecular dynamics simulations and mutagenesis to reveal force-induced rotational conformational changes of MICA, involving formation of additional hydrogen bonds on its binding interface with NKG2D, impeding MICA dissociation under force. We further provided a kinetic triggering model to reveal that force-dependent affinity determines NKG2D ligand discrimination and its downstream NK cell activation. Together, our results demonstrate that NKG2D has a discrimination power to recognize different ligands, which depends on selective mechanical force-induced ligand conformational changes.


Assuntos
Subfamília K de Receptores Semelhantes a Lectina de Células NK/química , Sítios de Ligação , Células Cultivadas , Antígenos de Histocompatibilidade Classe I/química , Antígenos de Histocompatibilidade Classe I/metabolismo , Humanos , Células K562 , Ligantes , Fenômenos Mecânicos , Simulação de Dinâmica Molecular , Subfamília K de Receptores Semelhantes a Lectina de Células NK/metabolismo , Ligação Proteica , Imagem Individual de Molécula
2.
J Nanobiotechnology ; 22(1): 343, 2024 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-38890749

RESUMO

The use of nanomaterials in gene editing and synthetic biology has emerged as a pivotal strategy in the pursuit of refined treatment methodologies for pulmonary disorders. This review discusses the utilization of nanomaterial-assisted gene editing tools and synthetic biology techniques to promote the development of more precise and efficient treatments for pulmonary diseases. First, we briefly outline the characterization of the respiratory system and succinctly describe the principal applications of diverse nanomaterials in lung ailment treatment. Second, we elaborate on gene-editing tools, their configurations, and assorted delivery methods, while delving into the present state of nanomaterial-facilitated gene-editing interventions for a spectrum of pulmonary diseases. Subsequently, we briefly expound on synthetic biology and its deployment in biomedicine, focusing on research advances in the diagnosis and treatment of pulmonary conditions against the backdrop of the coronavirus disease 2019 pandemic. Finally, we summarize the extant lacunae in current research and delineate prospects for advancement in this domain. This holistic approach augments the development of pioneering solutions in lung disease treatment, thereby endowing patients with more efficacious and personalized therapeutic alternatives.


Assuntos
COVID-19 , Edição de Genes , Pneumopatias , Nanoestruturas , Biologia Sintética , Edição de Genes/métodos , Humanos , Nanoestruturas/química , Nanoestruturas/uso terapêutico , Pneumopatias/genética , Pneumopatias/terapia , Biologia Sintética/métodos , COVID-19/terapia , COVID-19/genética , Animais , Sistemas CRISPR-Cas , SARS-CoV-2/genética , Terapia Genética/métodos
3.
Small ; 19(43): e2301798, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37357158

RESUMO

Electric double layer (EDL) devices based on 2D materials have made great achievements for versatile electronic and opto-electronic applications; however, the ion dynamics and electric field distribution of the EDL at the electrolyte/2D material interface and their influence on the physical properties of 2D materials have not been clearly clarified. In this work, by using Kelvin probe force microscope and steady/transient optical techniques, the character of the EDL and its influence on the optical properties of monolayer transition metal dichalcogenides (TMDs) are probed. The potential drop, unscreened EDL potential distribution, and accumulated carriers at the electrolyte/TMD interface are revealed, which can be explained by nonlinear Thomas-Fermi theory. By monitoring the potential distribution along the channel, the evolution of the electric field-induced lateral junction in the TMD EDL transistor is accessed, giving rise to the better exploration of EDL device physics. More importantly, EDL gate-dependent carrier recombination and exciton-exciton annihilation in monolayer TMDs on lithium-ion solid state electrolyte (Li2 Al2 SiP2 TiO13 ) are evaluated for the first time, benefiting from the understanding of the interaction between ions, carriers, and excitons. The work will deepen the understanding of the EDL for the exploitation of functional device applications.

4.
Mol Cell ; 57(3): 456-66, 2015 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-25601754

RESUMO

Shuttling of macromolecules between different cellular compartments helps regulate the timing and extent of different cellular activities. Here, we report that LC3, a key initiator of autophagy that cycles between the nucleus and cytoplasm, becomes selectively activated in the nucleus during starvation through deacetylation by the nuclear deacetylase Sirt1. Deacetylation of LC3 at K49 and K51 by Sirt1 allows LC3 to interact with the nuclear protein DOR and return to the cytoplasm with DOR, where it is able to bind Atg7 and other autophagy factors and undergo phosphatidylethanolamine conjugation to preautophagic membranes. The association of deacetylated LC3 with autophagic factors shifts LC3's distribution from the nucleus toward the cytoplasm. Thus, an acetylation-deacetylation cycle ensures that LC3 effectively redistributes in an activated form from nucleus to cytoplasm, where it plays a central role in autophagy to enable the cell to cope with the lack of external nutrients.


Assuntos
Autofagia , Núcleo Celular/metabolismo , Lisina/metabolismo , Proteínas Associadas aos Microtúbulos/metabolismo , Sirtuína 1/metabolismo , Acetilação , Proteína 7 Relacionada à Autofagia , Citoplasma/metabolismo , Células HEK293 , Células HeLa , Humanos , Microscopia Confocal , Proteínas Associadas aos Microtúbulos/genética , Proteínas Associadas aos Microtúbulos/ultraestrutura , Enzimas Ativadoras de Ubiquitina/metabolismo
5.
Ecotoxicol Environ Saf ; 252: 114572, 2023 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-36706524

RESUMO

Triclocarban (TCC) is a broad-spectrum antibacterial agent used globally, and high concentrations of this harmful chemical exist in the environment. The human body is directly exposed to TCC through skin contact. Moreover, TCC is also absorbed through diet and inhaled through breathing, which results in its accumulation in the body. The safety profile of TCC and its potential impact on human health are still not completely clear; therefore, it becomes imperative to evaluate the reproductive toxicity of TCC. Here, we explored the effect of TCC on the early embryonic development of mice and its associated mechanisms. We found that acute exposure of TCC affected the early embryonic development of mice in a dose-dependent manner. Approximately 7600 differentially expressed genes (DEGs) were obtained by sequencing the transcriptome of 2-cell mouse embryos; of these, 3157 genes were upregulated and 4443 genes were downregulated in the TCC-treated embryos. GO and KEGG analysis revealed that the enriched genes were mainly involved in redox processes, RNA synthesis, DNA damage, apoptosis, mitochondria, endoplasmic reticulum, Golgi apparatus, cytoskeleton, peroxisome, RNA polymerase, and other components or processes. Moreover, the Venn analysis showed that the zygotic genome activation (ZGA) was affected and the degradation of maternal effector genes was inhibited. TCC induced changes in the epigenetic modification of 2-cell embryos. The level of DNA methylation increased significantly. Further, the levels of H3K27ac, H3K9ac, and H3K27me3 histone modifications decreased significantly, whereas those of H3K4me3 and H3K9me3 modifications increased significantly. Additionally, TCC induced oxidative stress and DNA damage in the 2-cell embryos. In conclusion, acute exposure of TCC affected early embryo development, destroyed early embryo gene expression, interfered with ZGA and maternal gene degradation, induced changes in epigenetic modification of early embryos, and led to oxidative stress and DNA damage in mouse early embryos.


Assuntos
Carbanilidas , Desenvolvimento Embrionário , Humanos , Desenvolvimento Embrionário/genética , Carbanilidas/toxicidade , Metilação de DNA , Epigênese Genética , Zigoto/metabolismo , Regulação da Expressão Gênica no Desenvolvimento
6.
Environ Toxicol ; 38(12): 2904-2914, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37555465

RESUMO

Bisphenol AF (BPAF), a BPA-substitute, has been widely used in industrial compounds throughout the world. Several studies have shown that BPAF has endocrine interference and reproductive toxicity. However, the toxic effects of BPAF on pregnancy and placenta of goats are still unclear. Therefore, the objective of this study was to reveal the toxic effect of BPAF by using an in vitro culture model of caprine endometrial epithelial cells (EECs) and further attempted to alleviate the toxicity by curcumin pretreatment. The results showed that BPAF induces significant effects on EECs, including decreased cell viability and mitochondrial membrane potential (△ψm), elevating intracellular reactive oxygen species (ROS), promoting cell apoptosis through upregulating the expression of Bax, Cytochrome c, and downregulating the expression of Bcl-2. Meanwhile, BPAF induced dysregulation of oxidative stress by increasing the levels of malondialdehyde (MDA) and glutathione peroxidase (GSH-Px) but decreasing the activities of superoxide dismutase (SOD). However, curcumin pretreatment could significantly attenuate BPAF-induced toxic effects in EECs. Further study revealed that BPAF treatment could activate mitogen-activated protein kinase (MAPK) pathway and nuclear factor-erythroid 2-related factor 2 (Nrf2) expression, but curcumin pretreatment significantly inhibited the activation of MAPK signal pathway and Nrf2 expression induced by BPAF. Overall, this study indicated that curcumin could prevent BPAF-induced EECs cytotoxicity, which provides a potential therapeutic strategy for female infertility associated with BPAF exposure.


Assuntos
Curcumina , Animais , Feminino , Curcumina/farmacologia , Fator 2 Relacionado a NF-E2 , Cabras , Estresse Oxidativo , Transdução de Sinais , Proteínas Quinases Ativadas por Mitógeno , Células Epiteliais , Apoptose
7.
Small ; 17(14): e2006955, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33711196

RESUMO

T cell based-immunotherapy has been a powerful strategy to eradicate tumor cells in clinical trials. Effectively expanding the therapeutic T cells for clinical demand is still a challenge. Here, artificial antigen-presenting scaffolds are created for T cell ex vivo expansion. The antigen-presenting hybrid colloidal crystal clusters (HCCCs) with multiple stimuli are generated by internal encapsulation with prosurvival cytokines and surface decoration with activating antibodies to CD3ε and CD28, respectively. With the large loading capacity endowed by their abundant nanoporous structures, the antigen-presenting HCCCs can constantly release prosurvival cytokine IL-2. It is found that following the direct and multiple stimulations, the antigen-presenting HCCCs can effectively promote the expansion of T cells, which exhibits robust antitumor activity in vitro. Thus, the antigen-presenting HCCCs provide a novel expansion platform for clinical manufacturing of T cells.


Assuntos
Células Apresentadoras de Antígenos , Antígenos CD28 , Proliferação de Células , Imunoterapia , Linfócitos T
8.
Eur Radiol ; 31(11): 8160-8167, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33956178

RESUMO

OBJECTIVE: To compare the performance of a deep learning (DL)-based method for diagnosing pulmonary nodules compared with radiologists' diagnostic approach in computed tomography (CT) of the chest. MATERIALS AND METHODS: A total of 150 pathologically confirmed pulmonary nodules (60% malignant) assessed and reported by radiologists were included. CT images were processed by the proposed DL-based method to generate the probability of malignancy (0-100%), and the nodules were divided into the groups of benign (0-39.9%), indeterminate (40.0-59.9%), and malignant (60.0-100%). Taking the pathological results as the gold standard, we compared the diagnostic performance of the proposed DL-based method with the radiologists' diagnostic approach using the McNemar-Bowker test. RESULTS: There was a statistically significant difference between the diagnosis results of the proposed DL-based method and the radiologists' diagnostic approach (p < 0.001). Moreover, there was no statistically significant difference in the composition of the diagnosis results between the proposed DL-based method and the radiologists' diagnostic approach (all p > 0.05). The difference in diagnostic accuracy between the proposed DL-based method (70%) and radiologists' diagnostic performance (64%) was not statistically significant (p = 0.243). CONCLUSIONS: The proposed DL-based method achieved an accuracy comparable with the radiologists' diagnostic approach in clinical practice. Furthermore, its advantage in improving diagnostic certainty may raise the radiologists' confidence in diagnosing pulmonary nodules and may help clinical management. Therefore, the proposed DL-based method showed great potential in a certain clinical application. KEY POINTS: • Deep learning-based method for diagnosing the pulmonary nodules in computed tomography provides a higher diagnostic certainty.


Assuntos
Aprendizado Profundo , Neoplasias Pulmonares , Nódulos Pulmonares Múltiplos , Nódulo Pulmonar Solitário , Humanos , Neoplasias Pulmonares/diagnóstico por imagem , Nódulos Pulmonares Múltiplos/diagnóstico por imagem , Nódulo Pulmonar Solitário/diagnóstico por imagem , Tomografia Computadorizada por Raios X
9.
Phys Chem Chem Phys ; 23(35): 19457-19464, 2021 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-34524283

RESUMO

Reactive force field (ReaxFF) is a powerful computational tool for exploring material properties. In this work, we proposed an enhanced reactive force field model, which uses message passing neural networks (MPNN) to compute the bond order and bond energies. MPNN are a variation of graph neural networks (GNN), which are derived from graph theory. In MPNN or GNN, molecular structures are treated as a graph and atoms and chemical bonds are represented by nodes and edges. The edge states correspond to the bond order in ReaxFF and are updated by message functions according to the message passing algorithms. The results are very encouraging; the investigation of the potential, such as the potential energy surface, reaction energies and equation of state, are greatly improved by this simple improvement. The new potential model, called reactive force field with message passing neural networks (ReaxFF-MPNN), is provided as an interface in an atomic simulation environment (ASE) with which the original ReaxFF and ReaxFF-MPNN potential models can do MD simulations and geometry optimizations within the ASE. Furthermore, machine learning, based on an active learning algorithm and gradient optimizer, is designed to train the model. We found that the active learning machine not only saves the manual work to collect the training data but is also much more effective than the general optimizer.

10.
Acta Pharmacol Sin ; 42(5): 780-790, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-32814819

RESUMO

Guangsangon E (GSE) is a novel Diels-Alder adduct isolated from leaves of Morus alba L, a traditional Chinese medicine widely applied in respiratory diseases. It is reported that GSE has cytotoxic effect on cancer cells. In our research, we investigated its anticancer effect on respiratory cancer and revealed that GSE induces autophagy and apoptosis in lung and nasopharyngeal cancer cells. We first observed that GSE inhibits cell proliferation and induces apoptosis in A549 and CNE1 cells. Meanwhile, the upregulation of autophagosome marker LC3 and increased formation of GFP-LC3 puncta demonstrates the induction of autophagy in GSE-treated cells. Moreover, GSE increases the autophagy flux by enhancing lysosomal activity and the fusion of autophagosomes and lysosomes. Next, we investigated that endoplasmic reticulum (ER) stress is involved in autophagy induction by GSE. GSE activates the ER stress through reactive oxygen species (ROS) accumulation, which can be blocked by ROS scavenger NAC. Finally, inhibition of autophagy attenuates GSE-caused cell death, termed as "autophagy-mediated cell death." Taken together, we revealed the molecular mechanism of GSE against respiratory cancer, which demonstrates great potential of GSE in the treatment of representative cancer.


Assuntos
Antineoplásicos Fitogênicos/uso terapêutico , Autofagia/efeitos dos fármacos , Benzofuranos/uso terapêutico , Morus/química , Neoplasias/tratamento farmacológico , Resorcinóis/uso terapêutico , Animais , Antineoplásicos Fitogênicos/farmacologia , Apoptose/efeitos dos fármacos , Benzofuranos/farmacologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Feminino , Humanos , Camundongos Endogâmicos BALB C , Camundongos Nus , Folhas de Planta/química , Espécies Reativas de Oxigênio/metabolismo , Resorcinóis/farmacologia , Ensaios Antitumorais Modelo de Xenoenxerto
11.
J Comput Assist Tomogr ; 45(6): 888-893, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34469908

RESUMO

OBJECTIVE: To compare image quality and radiation dose of split-filter TwinBeam dual-energy (SF-TBDE) with those of single-energy images (SECT) in the contrast-enhanced chest computed tomography (CT). METHODS: Two hundred patients who underwent SF-TBDE (n = 100) and SECT (n = 100) contrast-enhanced chest scanning were retrospectively analyzed. The contrast-to-noise ratio (CNR) and figure of merit (FOM)-CNR of 5 structures (lung, aorta, pulmonary artery, thyroid, and erector spinae) were calculated and subjectively evaluated by 2 independent radiologists. Radiation dose was compared using volume CT dose index and size-specific dose estimate. RESULTS: The CNR and FOM-CNR of lung and erector spinae in SF-TBDE were higher than those of SECT (P < 0.001). The differences in the subjective image quality between the 2 groups were not significant (P = 0.244). Volume CT dose index and size-specific dose estimate of SF-TBDE were lower than those of SECT (6.60 ± 1.56 vs 7.81 ± 3.02 mGy, P = 0.001; 9.25 ± 1.60 vs. 10.55 ± 3.54; P = 0.001). CONCLUSIONS: The SF-TBDE CT can provide similar image quality at a lower radiation dose compared with SECT.


Assuntos
Meios de Contraste , Doses de Radiação , Intensificação de Imagem Radiográfica/métodos , Imagem Radiográfica a Partir de Emissão de Duplo Fóton/métodos , Radiografia Torácica/métodos , Doenças Torácicas/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , China , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Estudos Retrospectivos
12.
Nanomedicine ; 32: 102333, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33188908

RESUMO

Natural killer (NK) cells have exhibited therapeutic potential for various malignant tumors. However, the cytotoxic effect of NK cells is relatively weak and less specific compared to other immunotherapy approaches such as chimeric antigen receptor T-Cell (CART) therapy, constituting a great challenge for adoptive immunotherapy. Here, we report cell membrane-encapsulated magnetic nanoparticles for activating NK cells and enhancing anti-tumor effects. Magnetic nanoparticles were coated with silicon dioxide (SiO2), and cancer cell membranes were mixed with Fe3O4@SiO2 to construct cancer cell membrane coated Fe3O4@SiO2 magnetic nanoparticles (CMNPs). The functionalized nanoparticles bearing cancer-specific antigens on the surface effectively stimulated NK cells by enhancing expression of surface activating receptors and boosting anti-tumor function through the secretion of soluble cytotoxic effectors. To conclude, the biomimetic magnetic nanoparticles offer a versatile and powerful tool to present tumor-specific antigens, priming anti-tumor capability, which is promising to enhance NK cell-based adoptive cancer immunotherapy.


Assuntos
Membrana Celular/química , Imunoterapia , Células Matadoras Naturais/imunologia , Nanopartículas de Magnetita/química , Neoplasias/imunologia , Neoplasias/terapia , Antígenos de Neoplasias/metabolismo , Linhagem Celular Tumoral , Citotoxicidade Imunológica , Humanos , Ativação Linfocitária/imunologia , Nanopartículas de Magnetita/ultraestrutura
13.
Molecules ; 24(7)2019 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-30987021

RESUMO

An alternating synergetic ultrasound/microwave method was applied to the simultaneous extraction of essential oils and polysaccharides with deep eutectic solvent (DES) from Schisandra chinensis. Under the optimal conditions, extract in the selected choline chloride-ethylene glycol 1:3 solvent yielded 12.2 mL/kg and 8.56 g/100g of essential oils and polysaccharides, respectively. The free radical scavenging and immunological activities of the polysaccharides and the antioxidant activity of the essential oils have also been investigated. The lymphocyte proliferation capacity was substantially improved by adding concanavalin A or lipopolysaccharides to polysaccharides (0.20 mg/mL). The IC50 values of the essential oils for scavenging DPPH obtained by hydro-distillation and DES ultrasound/microwave-assisted hydro-distillation (DES UMHD) were 52.34 µg/mL and 29.82 µg/mL, respectively. The essential oil obtained by DES UMHD had the highest reducing power (856.05 (TE)/g) at 150 g/mL and had the strongest inhibitory capacity (SC% = 18.12%). S. chinensis has the potential to be developed as a natural antioxidant.


Assuntos
Destilação/métodos , Micro-Ondas , Óleos Voláteis/química , Extratos Vegetais/química , Polissacarídeos/química , Schisandra/química , Ondas Ultrassônicas
14.
Cell Biochem Funct ; 36(1): 13-17, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29277915

RESUMO

Recent evidence suggested a positive correlation between environmental estrogens (EEs) and high incidence of abnormalities in male urogenital system, but the mechanism remains unclear. Diethylstilbestrol (DES) is a nonsteroidal synthetic estrogen that disrupts the morphology and proliferation of gubernaculum testis cells, but the underlying mechanism is unclear. In this study, mouse gubernaculum testis cells were pretreated with phospholipase C (PLC) inhibitor U-73122 and then treated with DES. The results demonstrated that U-73122 impaired DES-evoked intracellular Ca2+ mobilization in gubernaculum testis cells and inhibited DES-induced proliferation of gubernaculum testis cells. Mechanistically, we found that U-73122 inhibited DES-induced activation of cAMP-response element binding protein (CREB) in gubernaculum testis cells. In conclusion, these data suggest that the effects of DES on mouse gubernaculum testis cells are mediated by PLC-Ca2+ -CREB pathway. SIGNIFICANCE OF THE STUDY: Environmental estrogens remain a serious threat to male reproductive health, and it is important to understand the mechanism by which EEs affect the male productive system. Here we explore potential mechanisms how the proliferation and contractility of gubernaculum testis cells are regulated by diethylstilbestrol. Our findings provide the first evidence that PLC-Ca2+ -CREB signalling pathway mediates the nongenomic effects of diethylstilbestrol on gubernaculum testis cells. These findings provide new insight into the role of diethylstilbestrol in the aetiology of male reproductive dysfunction and will help develop better approaches for the prevention and therapy of male reproductive malformation.


Assuntos
Cálcio/metabolismo , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , Dietilestilbestrol/farmacologia , Gubernáculo/efeitos dos fármacos , Testículo/efeitos dos fármacos , Fosfolipases Tipo C/metabolismo , Animais , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Estrenos/farmacologia , Gubernáculo/citologia , Gubernáculo/metabolismo , Masculino , Camundongos , Pirrolidinonas/farmacologia , Testículo/citologia , Testículo/metabolismo , Fosfolipases Tipo C/antagonistas & inibidores
15.
Molecules ; 23(9)2018 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-30154355

RESUMO

As a traditional medicinal herb and valuable natural spice in China, Aquilaria sinensis (Lour.) Gilg has many significant pharmacological effects. Agarwood is the resinous heartwood acquired from wounded A. sinensis trees, and is widely used in pharmaceuticals owing to its excellent medicinal value. In this study, the chemical composition of volatile components and alcohol extracts from different organs of A. sinensis and agarwoods grown in different regions were investigated using GC-MS. The results showed that Vietnam agarwood had the highest moisture content, which was attributed to the local climate, while the fruit and bark of A. sinensis had higher moisture contents than the other organs. The volatile components of A. sinensis organs included 3-ethyl-5-(2-ethylbutyl)-octadecane, oleic acid 3-(octadecyloxy) propyl ester, and docosanoic acid 1,2,3-propanetriyl ester, while the alcohol extracts of A. sinensis organs contained benzoic acid ethyl ester, hexadecanoic acid ethyl ester, oleic acid, and n-hexadecanoic acid. Furthermore, the main active ingredients in agarwood from different habitats were sesquiterpenoids, aromatic species, and chromone compounds. The role of chromone compound 2-phenylethyl-benzopyran as an elicitor and the mechanism of agarwood formation were also investigated. Antioxidant tests showed that essential oils from agarwood and A. sinensis had antioxidant capacities by comparison with butylated hydroxytoluene and vitamin E. An antibacterial activity test showed that the inhibition effect of the essential oil was better against Gram-positive bacteria than against Gram-negative bacteria.


Assuntos
Cromatografia Gasosa-Espectrometria de Massas , Compostos Fitoquímicos/análise , Compostos Fitoquímicos/química , Thymelaeaceae/química , Madeira/química , Antibacterianos/análise , Antibacterianos/química , Antibacterianos/farmacologia , Antioxidantes/análise , Antioxidantes/química , Antioxidantes/farmacologia , Testes de Sensibilidade Microbiana , Estrutura Molecular , Óleos Voláteis , Compostos Fitoquímicos/farmacologia , Extratos Vegetais/análise , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Compostos Orgânicos Voláteis/análise , Compostos Orgânicos Voláteis/química , Compostos Orgânicos Voláteis/farmacologia
16.
Molecules ; 22(7)2017 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-28640212

RESUMO

The emergence of drug resistant variants of the influenza virus has led to a great need to identify novel and effective antiviral agents. In our previous study, a series of sialic acid (C-2 and C-4)-pentacyclic triterpene conjugates have been synthesized, and a five-fold more potent antiviral activity was observed when sialic acid was conjugated with pentacyclic triterpene via C-4 than C-2. It was here that we further reported the synthesis and anti-influenza activity of novel sialic acid (C-5 and C-9)-pentacyclic triterpene conjugates. Their structures were confirmed by ESI-HRMS, ¹H-NMR, and 13C-NMR spectroscopic analyses. Two conjugates (26 and 42) showed strong cytotoxicity to MDCK cells in the CellTiter-Glo assay at a concentration of 100 µM. However, they showed no significant cytotoxicity to HL-60, Hela, and A549 cell lines in MTT assay under the concentration of 10 µM (except compound 42 showed weak cytotoxicity to HL-60 cell line (10 µM, ~53%)). Compounds 20, 28, 36, and 44 displayed weak potency to influenza A/WSN/33 (H1N1) virus (100 µM, ~20-30%), and no significant anti-influenza activity was found for the other conjugates. The data suggested that both the C-5 acetylamide and C-9 hydroxy of sialic acid were important for its binding with hemagglutinin during viral entry into host cells, while C-4 and C-2 hydroxy were not critical for the binding process and could be replaced with hydrophobic moieties. The research presented herein had significant implications for the design of novel antiviral inhibitors based on a sialic acid scaffold.


Assuntos
Antivirais/síntese química , Antivirais/farmacologia , Vírus da Influenza A Subtipo H1N1/efeitos dos fármacos , Ácido N-Acetilneuramínico/química , Triterpenos/síntese química , Triterpenos/farmacologia , Animais , Antivirais/química , Espectroscopia de Ressonância Magnética Nuclear de Carbono-13 , Linhagem Celular Tumoral , Cães , Glicoproteínas de Hemaglutininação de Vírus da Influenza/química , Humanos , Células Madin Darby de Rim Canino , Espectroscopia de Prótons por Ressonância Magnética , Espectrometria de Massas por Ionização por Electrospray , Triterpenos/química
17.
Tumour Biol ; 37(8): 11209-18, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26943799

RESUMO

Malignant melanoma is an aggressive, highly lethal dermatological malignancy. Chemoresistance and rapid metastasis limit the curative effect of multimodal therapies like surgery or chemotherapy. The suicide enzyme O6-methylguanine-DNA methyltransferase (MGMT) removes adducts from the O6-position of guanine to repair DNA damage. High MGMT expression is associated with resistance to therapy in melanoma. However, it is unknown if MGMT is regulated by DNA methylation or histone acetylation in melanoma. We examined the effects of the DNA methylation inhibitor 5-Aza-2'-deoxycytidine and histone deacetylase inhibitor Trichostatin A alone or in combination on MGMT expression and promoter methylation and histone acetylation in A375, MV3, and M14 melanoma cells. This study demonstrates that MGMT expression, CpG island methylation, and histone acetylation vary between melanoma cell lines. Combined treatment with 5-Aza-2'-deoxycytidine and Trichostatin A led to reexpression of MGMT, indicating that DNA methylation and histone deacetylation are associated with silencing of MGMT in melanoma. This study provides information on the role of epigenetic modifications in malignant melanoma that may enable the development of new strategies for treating malignant melanoma.


Assuntos
Metilação de DNA/genética , Metilases de Modificação do DNA/biossíntese , Enzimas Reparadoras do DNA/biossíntese , Resistencia a Medicamentos Antineoplásicos/genética , Regulação Neoplásica da Expressão Gênica/genética , Histonas/metabolismo , Melanoma/genética , Proteínas Supressoras de Tumor/biossíntese , Acetilação , Antineoplásicos/farmacologia , Western Blotting , Linhagem Celular Tumoral , Imunoprecipitação da Cromatina , Dacarbazina/análogos & derivados , Dacarbazina/farmacologia , Humanos , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Neoplasias Cutâneas/genética , Temozolomida
18.
Bioorg Med Chem ; 24(21): 5197-5205, 2016 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-27594550

RESUMO

A series of arylidene N-alkoxydiketopiperazines was designed and stereoselectively synthesized via oxime-ether formation and intramolecular acylation. Possible cyclization and acid-catalyzed rearrangement-fragmentation mechanisms were discussed. The crystal structure of the novel diketopiperazine further confirmed the rearrangement mechanism. Most compounds exhibited antitumor activity. Several compounds were more potent against caspase-3. Specifically, compounds 6e, 6g, and 6f inhibited caspase-3 at IC50 values lying within the low micromolar range and demonstrated good selectivity. The binding modes of alkoxydiketopiperazines in the active center of caspase-3 were also discussed based on the molecular docking results.


Assuntos
Antineoplásicos/farmacologia , Caspase 3/metabolismo , Dicetopiperazinas/farmacologia , Inibidores Enzimáticos/farmacologia , Peptídeos Cíclicos/farmacologia , Antineoplásicos/síntese química , Antineoplásicos/química , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Cristalografia por Raios X , Dicetopiperazinas/síntese química , Dicetopiperazinas/química , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/química , Humanos , Modelos Moleculares , Estrutura Molecular , Peptídeos Cíclicos/síntese química , Peptídeos Cíclicos/química , Relação Estrutura-Atividade
19.
World J Surg ; 38(4): 947-57, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24258262

RESUMO

OBJECTIVE: The aim of this study was to investigate the prognostic value of tumor size alone on long-term survival and recurrence after curative resection for solitary hepatocellular carcinoma (HCC) without macroscopic vascular invasion. METHODS: A single-center cohort of 615 patients with solitary HCC (a single tumor, without macroscopic vascular invasion or distant metastasis) undergoing curative hepatic resection from 2002 to 2010 was retrospectively studied. Using 2.0, 3.0, 4.0, 5.0, 8.0, and 10.0 cm as cut-off values of tumor size, the overall survival (OS) and recurrence-free survival (RFS) rates were compared between the groups of patients with tumor size up to a certain cut-off value and the groups of patients with tumor size above that cut-off value. Thus, multiple comparisons were done. The prognostic factors of OS and RFS were evaluated using univariate and multivariate analyses. RESULTS: The median tumor size of all HCCs was 4.0 cm (range 0.9-22.0 cm). The in-hospital mortality rate was 1.0 %, and the overall morbidity rate was 22.3 %. The 1-, 3-, and 5-year OS rates were 96.0, 79.8, and 69.9 %, and the corresponding RFS rates were 83.6, 72.7, and 57.2 %, respectively. On univariate analyses, the 1-, 3-, and 5-year OS and RFS rates were significantly different between the individual two groups of patients as divided by the aforementioned different cut-off values of tumor sizes (all p < 0.05). However, when tumor size was put as a continuous variable into multivariate analysis, it was no longer an independent prognostic factor of OS or RFS after curative resection. CONCLUSIONS: Tumor size did not independently affect long-term survival and recurrence after curative resection of solitary HCC without macroscopic vascular invasion. Therefore, there is no size limit that precludes hepatic resection for solitary HCC, provided the tumor is resectable.


Assuntos
Carcinoma Hepatocelular/cirurgia , Hepatectomia , Neoplasias Hepáticas/cirurgia , Carga Tumoral , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma Hepatocelular/mortalidade , Carcinoma Hepatocelular/patologia , Criança , Feminino , Seguimentos , Mortalidade Hospitalar , Humanos , Neoplasias Hepáticas/mortalidade , Neoplasias Hepáticas/patologia , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Invasividade Neoplásica , Recidiva Local de Neoplasia/patologia , Prognóstico , Estudos Retrospectivos , Análise de Sobrevida , Resultado do Tratamento , Adulto Jovem
20.
Adv Healthc Mater ; : e2401085, 2024 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-38796738

RESUMO

Cellular senescence is a significant risk factor for aging and age-related diseases (ARD). The canonical senolytics Dasatinib and Quercetin (DQ) have shown promise in clearing senescent cells (SnCs); however, the lack of selectivity poses a challenge in achieving optimal outcomes. Despite the recent occurrence of nanomaterial-based approaches targeting SnCs, limited therapeutic effects, and potential toxicity still remain a major concern. Herein, a "double locks-like" nanoplatform is developed that integrated Galactan coating and mesoporous polydopamine to encase the senolytic drug DQ. By this way, DQ is only released in SnCs that are featured with higher levels of ß-galactosidase (ß-gal) and low PH. Additionally, the nanoparticles are equipped with 2,2,6,6-Tetramethylpiperidine-1-oxyl (Tempo) to gain enhanced photothermal converting potential. Consequently, the synthesized nanosenolytics demonstrate remarkable specificity and efficacy in eradicating SnCs, and accordingly reverse pulmonary fibrosis in mice without affecting normal tissues. Upon exposure of near-infrared (NIR) light, the nanoparticles demonstrate to efficiently remove senescent tumor cells inducted by chemotherapy, thereby hindering the outgrowth and metastasis or breast cancer. Collectively, the present study develops an "On/Off" switchable nanoplatform in response to SnCs, and produces a more safe, efficient, and feasible way to delay aging or alleviate age-associated diseases.

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