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1.
J Chem Inf Model ; 64(7): 2854-2862, 2024 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-37565997

RESUMO

Identifying synergistic drug combinations is fundamentally important to treat a variety of complex diseases while avoiding severe adverse drug-drug interactions. Although several computational methods have been proposed, they highly rely on handcrafted feature engineering and cannot learn better interactive information between drug pairs, easily resulting in relatively low performance. Recently, deep-learning methods, especially graph neural networks, have been widely developed in this area and demonstrated their ability to address complex biological problems. In this study, we proposed AttenSyn, an attention-based deep graph neural network for accurately predicting synergistic drug combinations. In particular, we adopted a graph neural network module to extract high-latent features based on the molecular graphs only and exploited the attention-based pooling module to learn interactive information between drug pairs to strengthen the representations of drug pairs. Comparative results on the benchmark datasets demonstrated that our AttenSyn performs better than the state-of-the-art methods in the prediction of anticancer synergistic drug combinations. Additionally, to provide good interpretability of our model, we explored and visualized some crucial substructures in drugs through attention mechanisms. Furthermore, we also verified the effectiveness of our proposed AttenSyn on two cell lines by visualizing the features of drug combinations learnt from our model, exhibiting satisfactory generalization ability.


Assuntos
Benchmarking , Aprendizagem , Linhagem Celular , Redes Neurais de Computação
2.
Int J Biol Macromol ; 256(Pt 1): 128324, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38007026

RESUMO

A comprehensive understanding of the complex regulatory mechanisms governing estrus and ovulation across multiple tissues in mammals is imperative to improve the reproductive performance of livestock and mitigate ovulation-related disorders in humans. To comprehensively elucidate the regulatory landscape, we analyzed the transcriptome of protein-coding genes and long intergenic non-coding RNAs (lincRNAs) in 58 samples (including the hypothalamus, pituitary, ovary, vagina, and vulva) derived from European Large White gilts and Chinese Mi gilts during estrus and diestrus. We constructed an intricate regulatory network encompassing 358 hub genes across the five examined tissues. Furthermore, our investigation identified 85 differentially expressed lincRNAs that are predicted to target 230 genes associated with critical functions including behavior, receptors, and apoptosis. Importantly, we found that vital components of estrus and ovulation events involve "Apoptosis" pathway in the hypothalamus, "Autophagy" in the ovary, as well as "Hypoxia" and "Angiogenesis" in the vagina and vulva. We have identified several differentially expressed transcription factors (TFs), such as SPI1 and HES2, which regulate these pathways. SPI1 may suppress transcription in the autophagy pathway, promoting apoptosis and inhibiting the proliferation of ovarian granulosa cells. Our study provides the most comprehensive transcriptional profiling information related to estrus and ovulation events.


Assuntos
RNA Longo não Codificante , Transcriptoma , Humanos , Suínos , Feminino , Animais , Transcriptoma/genética , Diestro/fisiologia , Estro/genética , Sus scrofa/genética
3.
Artigo em Inglês | MEDLINE | ID: mdl-38083581

RESUMO

This paper reports a three-dimensional microfluidic device with an array of vertical channels to enable regulated, continuous, vertical flows to emulate the environment for in vitro culturing of brain and blood vessel organoids. This is expected to ultimately lead to in vitro reconstruction of the blood-brain barrier that is of high interest to studies on mental illness mechanisms and drug delivery to the brain. Twelve vertical microfluidic channels, each with 300 µm diameter and 5 mm height, were formed in the high-permeability agar gel surrounding the organoid to realize the vertical circulation flows and to allow lateral diffusion flows. The combined vertical flow rate of all channels ranges from 2.1 to 6.8 mL/min under different control parameters. A 30-day-old human blood vessel organoid was planted into the device for initial culturing and flow function tests. The result indicates that the organoid was properly activated with effective flow generation in the culturing site of the device.


Assuntos
Barreira Hematoencefálica , Microfluídica , Humanos , Difusão , Encéfalo , Dispositivos Lab-On-A-Chip
4.
Free Radic Biol Med ; 203: 69-85, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37044149

RESUMO

Adiponectin receptor 2 (AdipoR2) can be activated by its endogenous ligand adiponectin to reduce hepatic steatosis, and is regarded as a therapeutic target for metabolic associated fatty liver disease (MAFLD). This study proposes a novel anthraquinone compound, emodin succinate monoethyl ester (ESME), which activates AdipoR2, inhibits hepatic lipogenesis, promotes fatty acid oxidation, and alleviates experimental hepatic steatosis in hamsters and mice. Molecular docking shows that ESME has strong binding potential with AdipoR2 by forming a arene-arene interaction. AdipoR2 on the cytomembrane of HepG2 cells can be labeled by fluorescent ESME (Cy5-ESME). ESME activates AdipoR2, AMPK and PPARα, and reduces lipid deposition in palmitic acid or oleic acid-induced HepG2 and L02 cells. Suppression of AdipoR2 expression or AMPK activation completely eliminates the effect of ESME on reducing lipid accumulation in hepatocytes. Oral administration of ESME reduces liver lipid production and accumulation, and alleviates hepatic steatosis in hamsters and Apoe-/- mice induced by high-fat diet. Compared with statins and emodin, ESME showed prepotent efficacy and safety in reducing hepatic steatosis and protecting hepatocytes. Furthermore, ESME activates CaMKK2 and LKB1 in liver to activate AMPK and reduce lipogenesis through stimulating AdipoR2. Taken together, ESME reduces hepatic lipid accumulation and alleviates hepatic steatosis by agonizing AdipoR2. ESME is a promising new agent for clinical treatment of MAFLD.


Assuntos
Emodina , Hepatopatia Gordurosa não Alcoólica , Camundongos , Animais , Cricetinae , Humanos , Proteínas Quinases Ativadas por AMP/metabolismo , Simulação de Acoplamento Molecular , Emodina/metabolismo , Emodina/farmacologia , Emodina/uso terapêutico , Fígado/metabolismo , Hepatócitos/metabolismo , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Hepatopatia Gordurosa não Alcoólica/metabolismo , Metabolismo dos Lipídeos , Células Hep G2 , Ácido Oleico/metabolismo , Dieta Hiperlipídica/efeitos adversos
5.
Inorg Chem ; 62(2): 685-693, 2023 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-36583612

RESUMO

Li-rich layered oxides (LLOs) are considered promising candidates for new high-energy-density cathode materials for next-generation power batteries. However, their large-scale applications are largely hindered by irreversible Li/O loss, structural degradation, and interfacial side reactions during cycling. Herein, we demonstrate an integration strategy that tunes the electronic structure by La/Al codoping and constructs a ferroelectric interface on the LLOs surface through Bi0.5Na0.5TiO3 (BNT) coating. Experimental characterization reveals that the synergistic effect of the ferroelectric interface and the well-tuned electronic structure can not only promote the diffusion of Li+ and hinder the migration of On- but also suppress the lattice volume changes and reduce interfacial side reactions at high voltages up to 4.9 V vs Li+/Li. As a result, the modified material shows enhanced initial capacities and retention rates of 224.4 mAh g-1 and 78.57% after 500 cycles at 2.0-4.65 V and 231.7 mAh g-1 and 85.76% after 200 cycles at 2.0-4.9 V at 1C, respectively.

6.
Int J Mol Sci ; 25(1)2023 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-38203196

RESUMO

In pig production, pigs often show more aggressive behavior after mixing, which adversely affects animal welfare and growth performance. The Jumonji and structural domain-rich AT interaction domain 2 (JARID2) gene plays an important role in neurodevelopment in mice and various psychiatric disorders in humans. The JARID2 gene may impact the aggressive behavior of pigs. By observing the behavior of 500 weaned pigs during the first 72 h after mixing, the ear tissue samples of the 12 most aggressive and 12 least aggressive pigs were selected for DNA resequencing based on the intensity of their aggressive behavior. Large group correlation analysis indicated that the rs3262221458 site located in the 3'-UTR region of the porcine JARID2 gene has a strong relationship with the aggressive behavior of weaned pigs. Pigs with the mutant TT genotype of rs3262221458 have more aggressive behavior than those pigs with the GG and GT genotypes. The dual luciferase assay indicated that the luciferase activity of the plasmids containing the G allele of rs326221458 was significantly less than that of plasmids containing the T allele of rs326221458 and control groups. The binding ability of miR-9828-3p to sequences containing the T allele was less than that of sequences containing the G allele. The overexpression of miR-9828-3p in porcine neuroglial cells (PNGCs) and PK15 cells significantly decreased the mRNA and protein levels of the JARID2 gene. In addition, miR-9828-3p inhibited the proliferation of PNGCs. After inhibiting miR-9828-3p, the mRNA and protein expression levels of JARID2 increased, and the proliferation of PNGCs showed an opposite trend to the cells that forced the expression of miR-9828-3p. In addition, interference with the JARID2 gene by siRNA can effectively inhibit the proliferation of PNGCs. In summary, we found that the rs326221458 locus regulates the expression of the JARID2 gene by affecting the binding of miR-9828-3p and the JARID2 gene, thereby affecting the aggressive behavior of weaned pigs after mixing.


Assuntos
MicroRNAs , Polimorfismo de Nucleotídeo Único , Humanos , Suínos/genética , Animais , Camundongos , Regiões 3' não Traduzidas , RNA Mensageiro , Luciferases , MicroRNAs/genética , Complexo Repressor Polycomb 2
7.
Front Cell Infect Microbiol ; 12: 827750, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35774408

RESUMO

Fusobacterium necrophorum can cause liver abscess, foot rot in ruminants, and Lemire syndrome in humans, Also, its virulence factors can induce the apoptosis of macrophages and neutrophils. However, the detailed mechanism has not been fully clarified. This study investigated the mechanisms of apoptosis and inflammatory factor production in F. necrophorum-induced neutrophils and macrophages (RAW246.7). After infection of macrophages with F. necrophorum, 5-ethynyl-2'-deoxyuridine labeling assays indicated that F. necrophorum inhibited macrophage proliferation in a time- and dose-dependent manner. Hoechst staining and DNA ladder assays showed significant condensation of the nucleus and fragmentation of genomic DNA in F. necrophorum-infected macrophages, Annexin V (FITC) and propidium iodide (PI) assay confirmed the emergence of apoptosis in the macrophages and sheep neutrophils with F. necrophorum compared with the control. The group with significant apoptosis was subjected to RNA sequencing (RNA-Seq), and the sequencing results revealed 2581 up- and 2907 downregulated genes. Gene Ontology and Kyoto Encyclopedia of Genes and Genomes analysis of the differentially expressed genes showed that F. necrophorum drove apoptosis and production of inflammatory factors by activating genes related to the Nuclear Factor-κB (NF-κB) and death receptor pathways. Meanwhile, quantitative reverse transcription PCR and Western blot validation results were consistent with the results of transcriptome sequencing analysis. In conclusion, F. necrophorum induced apoptosis and production of pro-inflammatory factors through the NF-κB and death receptor signaling pathway, providing a theoretical basis for further mechanistic studies on the prevention and control of F. necrophorum disease treatment.


Assuntos
Infecções por Fusobacterium , Fusobacterium necrophorum , Animais , Apoptose , Citocinas , Infecções por Fusobacterium/microbiologia , Infecções por Fusobacterium/veterinária , Fusobacterium necrophorum/genética , NF-kappa B , Receptores de Morte Celular , Ovinos , Transdução de Sinais
8.
Sensors (Basel) ; 22(3)2022 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-35161799

RESUMO

Weight-bearing exoskeletons are robots that need to carry loads and interact with humans frequently. Therefore, the actuators of these exoskeletons are supposed to be capable of outputting sufficient force with high compliance and little weight. A series-parallel elastic actuator (SPEA) is designed, in this work, to meet the demanding requirements of an exoskeleton robot called PALExo. A gas spring is installed in parallel with an electric cylinder to adjust the force output range of the actuator according to the needs of the exoskeleton. A series elastic module (SEM) is installed in series with the electric cylinder and gas spring to improve the compliance of the actuator, the stiffness of which is variable to adapt to the different stiffness requirements of the exoskeleton's legs in the standing phase and swinging phase. A force controller combining dynamic compensation and a cascade control with an inner velocity loop and a disturbance observer is designed for the SPEA. The performance of the force controller is verified by experiments and the results demonstrate that the controller has good adaptability to the stiffness of the SEM.


Assuntos
Exoesqueleto Energizado , Robótica , Módulo de Elasticidade , Desenho de Equipamento , Humanos , Suporte de Carga
9.
Soft Robot ; 9(1): 36-56, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-33275516

RESUMO

This article presents the design, fabrication, modeling, and preliminary tests of a bloodworm-inspired soft gripper for universal grasping. The gripper was designed and fabricated based on a toy called water snake wiggly (WSW). The toroidal WSW can evert itself inside-out or outside-in, just like a bloodworm everting its teeth outside to hunt and inside to feed. By driving a WSW rolling itself outside-in to wrap around the items, a bloodworm-inspired gripper was achieved with a flexible and passive form-fitting grasp. To enhance the capability of the gripper, two alternative detachable modules were added to the gripper-a vacuum suction cup for handling objects with smooth nonporous surfaces and an end-needle for taking in and expelling noncorrosive liquids like a syringe. We analyzed the working principles of the gripper and derived the relationship between the gripper's holding force and the objects' scale. Preliminary experiments with a motor-driven gripper prototype were conducted to verify its performance. The experimental results conform well with our theoretical analysis and also indicate the gripper's good universal grasping capacity and reliability in handling a wide range of objects with different surface shapes, geometric dimensions, and stiffness. In addition, the gripper has the unique abilities to pick more than one object during a maneuver, grasp multiple objects in a row without releasing the former ones, and even grasp powdered objects. These have presented a challenge for the existing robotic grippers.


Assuntos
Deglutição , Robótica , Desenho de Equipamento , Força da Mão , Reprodutibilidade dos Testes , Robótica/métodos
10.
Sensors (Basel) ; 21(18)2021 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-34577512

RESUMO

In order to meet the assist requirements of extravehicular activity (EVA) for astronauts, such as moving outside the international space station (ISS) or performing on-orbit tasks by a single astronaut, this paper proposes an astronaut robotic limbs system (AstroLimbs) for extravehicular activities assistance. This system has two robotic limbs that can be fixed on the backpack of the astronaut. Each limb is composed of several basic module units with identical structure and function, which makes it modularized and reconfigurable. The robotic limbs can work as extra arms of the astronaut to assist them outside the space station cabin. In this paper, the robotic limbs are designed and developed. The reinforcement learning method is introduced to achieve autonomous motion planning capacity for the robot, which makes the robot intelligent enough to assist the astronaut in unstructured environment. In the meantime, the movement of the robot is also planned to make it move smoothly. The structure scene of the ISS for extravehicular activities is modeled in a simulation environment, which verified the effectiveness of the proposed method.


Assuntos
Procedimentos Cirúrgicos Robóticos , Robótica , Voo Espacial , Astronautas , Simulação por Computador , Atividade Extraespaçonave , Humanos
11.
ACS Appl Mater Interfaces ; 13(38): 45619-45629, 2021 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-34530607

RESUMO

Lithium-rich manganese-based layered oxides (LLOs) are considered to be the most promising cathode materials for next-generation lithium-ion batteries (LIBs) for their higher reversible capacity, higher operating voltage, and lower cost compared with those of other commercially available cathode materials. However, irreversible lattice oxygen release and associated severe structural degradation that exacerbate under high temperature and deep delithiation hinder the large-scale application of LLOs. Herein, we propose a strategy to stabilize the layered lattice framework and improve the thermal stability of cobalt-free Li1.2Mn0.53Ni0.27O2 by doping with 4d transition metal niobium (Nb). Detailed atomic-scale imaging, in situ characterization, and DFT simulations confirm that the induced strong Nb-O bonds stabilize the oxygen lattice framework and restrains the fracture of TM-O bonds, thereby inhibiting the release of lattice oxygen and the continuous migration of TM ions to the lithium layer during the cycle. Furthermore, Nb doping also promotes the surface rearrangement to form a Ni-enrichment layered/rocksalt heterogeneous interface to enhance surface structural stability. As a result, the Nb-doped material delivers a capacity of 181.7 mAh g-1 with retention of 85.5% after 200 cycles at 1C, extraordinary thermal stability with a capacity retention of 80.7% after 200 cycles at 50 °C, and superior rate capability.

12.
Front Cardiovasc Med ; 8: 657544, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34307490

RESUMO

Background: Circular non-coding RNA (circRNA) has a variety of biological functions. However, the expression profile and potential effects of circRNA on atherosclerosis (AS) and vascular endothelial injury have not been fully elucidated. This study aims to identify the differentially expressed circRNAs in atherosclerotic aortic vessels and predict their potential functions in endothelial injury. Method: ApoE-/- mice were fed with high-fat diet for 12 weeks to induce AS. Atherosclerotic plaques were evaluated by H&E and Masson staining and immunohistochemistry; differentially expressed circRNAs were detected by Arraystar Circular RNA Microarray and verified by RT-PCR; the potential target mircoRNAs of circRNAs were predicted by miRanda, Tarbase, Targetscan and their expression changes were verified by RT-PCR; the potential target genes of mircoRNAs were predicted by Targetscan and verified by Western blot; the signaling pathways that they might annotate or regulate and their potential functions in vascular endothelial injury were predicted by gene enrichment analysis. Results: Fifty two circRNAs were up-regulated more than twice and 47 circRNAs were down-regulated more than 1.5 times in AS aortic vessels. Mmmu_circRNA_36781 and 37699 were up-regulated both in AS aortic vessels and H2O2-treated mouse aortic endothelial cells (MAECs). The expression of miR-30d-3p and miR-140-3p, the target microRNA of circRNA_37699 and circRNA_36781, were downregulated both in AS vessels and H2O2-treated MAECs. On the contrary, MKK6 and TP53RK, the potential target gene of miR-140-3p and miR-30d-3p, were upregulated both in AS aortic roots and H2O2-treated MAECs. Besides, gene enrichment analysis showed that MAPK and PI3K-AKT signaling pathway were the most potential signaling pathways regulated by the differentially expressed circRNAs in atherosclerosis. Conclusions: Mmu_circRNA_36781 (circRNA ABCA1) and 37699 (circRNA KHDRBS1) were significantly up-regulated in AS aortic vessels and H2O2-treated MAECs. They have potential regulatory effects on atherosclerosis and vascular endothelial injury by targeting miR-30d-3p-TP53RK and miR-140-3p-MKK6 axis and their downstream signaling pathways.

13.
ACS Appl Mater Interfaces ; 13(10): 12159-12168, 2021 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-33666083

RESUMO

Lithium-rich manganese-based layered oxide cathodes (LLOs) with oxygen redox reactions are considered to be potential candidates for the next generation of high-energy-density Li-ion batteries. However, the oxygen redox process that enables ultrahigh specific capacity usually leads to irreversible O2 release and cation migration, which induce structure degradation and severe capacity/voltage losses and thus limit the commercial application of LLOs. Herein, we successfully synthesized chlorine (Cl)-doped Co-free LLOs (Li1.2Mn0.53Ni0.27O1.976Cl0.024) and analyzed the effect of anion doping on oxygen redox and structure stability of LLOs. Cl doping has been proven to decrease the irreversible lattice oxygen loss to enhance the redox reversibility of oxygen and inhibit the transition-metal migration during cycles, which substantially enhances the capacity and voltage retention and improves the rate capability during cycling. This work provides new insights for the development of high-performance TM oxide cathode materials with reversible oxygen redox.

14.
Biosens Bioelectron ; 166: 112453, 2020 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-32862845

RESUMO

Developing photoactive materials with wide spectral response is critical to improve the sensitivity of PEC biosensors. Herein, a sensitive photoelectrochemical (PEC) aptasensor was fabricated based on Bi surface plasmon resonance (SPR)-promoted BiVO4/g-C3N4 (Bi/BiVO4/g-C3N4) as photoactive material for the detection of oxytetracycline (OTC). Ternary Z-scheme Bi/BiVO4/g-C3N4 heterojunction exhibited widest spectral response and best PEC activity compared to g-C3N4, BiVO4, Bi/BiVO4, and BiVO4/g-C3N4. The wide spectral response and high PEC activity could be attributed to three reasons: Firstly, the SPR effect of Bi could greatly increase light harvesting; Secondly, Bi served as an electron conduction bridge between BiVO4 and g-C3N4 to form Z-scheme structure, significantly accelerating the separation of photogenerated carriers; Thirdly, the synergism of Z-scheme heterojunction and the SPR effect of Bi efficiently boosted the photoelectric response. Based on the above sensitization strategies, the proposed PEC aptasensor for OTC determination showed a wide linear range of 0.01-1000 nM and a low detection limit (S/N = 3) of 3.3 × 10-3 nM. Moreover, the high stability, satisfactory repeatability and favorable practicability of the fabricated PEC aptasensor revealed the potential applications for accurate monitoring of antibiotics in environmental media.


Assuntos
Aptâmeros de Nucleotídeos , Técnicas Biossensoriais , Oxitetraciclina , Técnicas Eletroquímicas , Ressonância de Plasmônio de Superfície
15.
Technol Health Care ; 25(S1): 267-273, 2017 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-28582915

RESUMO

In this paper, an obstacle-surmounting-enabled lower limb exoskeleton with novel linkage joints that perfectly mimicked human motions was proposed. Currently, most lower exoskeletons that use linear actuators have a direct connection between the wearer and the controlled part. Compared to the existing joints, the novel linkage joint not only fitted better into compact chasis, but also provided greater torque when the joint was at a large bend angle. As a result, it extended the angle range of joint peak torque output. With any given power, torque was prioritized over rotational speed, because instead of rotational speed, sufficiency of torque is the premise for most joint actions. With insufficient torque, the exoskeleton will be a burden instead of enhancement to its wearer. With optimized distribution of torque among the joints, the novel linkage method may contribute to easier exoskeleton movements.


Assuntos
Membros Artificiais , Exoesqueleto Energizado , Articulação do Tornozelo/fisiologia , Fenômenos Biomecânicos , Articulação do Quadril/fisiologia , Humanos , Articulação do Joelho/fisiologia , Movimento , Desenho de Prótese/métodos , Amplitude de Movimento Articular/fisiologia
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