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The development of high-performance, stable and platinum-free electrocatalysts for the hydrogen oxidation reaction (HOR) in alkaline media is crucial for the commercial application of anion exchange membrane fuel cells (AEMFCs). Ruthenium, as an emerging HOR electrocatalyst with a price advantage over platinum, still needs to solve the problems of low intrinsic activity and easy oxidation. Herein, Ru nanoparticles are anchored on the oxygen-vacancy-rich metalloid WO2.9 by interfacial engineering to create abundant and efficient Ru and WO2.9 interfacial active sites for accelerated HOR in alkaline media. Ru/WO2.9/C displays excellent catalytic activity with mass activity (8.29 A mgNM -1) and specific activity (1.32 mA cmNM -2), which are 2.5/3.3 and 21.8/8.3 times that of PtRu/C and Pt/C, respectively. Moreover, Ru/WO2.9/C exhibits excellent CO tolerance and operational stability. Experimental and theoretical studies reveal that the improved charge transfer from Ru to WO2.9 in the metal/metalloid heterostructure significantly tune the electronic structure of Ru sites and optimize the hydrogen binding energy (HBE) of Ru. While, WO2.9 provides abundant hydroxyl adsorption sites. Therefore, the equilibrium adsorption of hydrogen and hydroxyl at the interface of Ru/WO2.9 will be realized, and the oxidation of metal Ru would be avoided, thereby achieving excellent HOR activity and durability.
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Designing robust catalysts for increasing the sluggish kinetics of the urea oxidation reaction (UOR) is challenging. Herein, the regulation of spin states for metal active sites by photoexcitation to facilitate the adsorption of urea and intermediates is demonstrated. Mo-doped nickel sulfide nanoribbon arrays (Mo-Ni3S2@NMF) with excellent light-trapping capacity are successfully prepared. Under AM 1.5G illumination, the activity of the Mo-Ni3S2@NMF exhibits a 50% improvement in the UOR current. Compared with those under dark conditions, Mo-Ni3S2@NMF achieve 10 mA cm-2 at 1.315 VRHE for UOR and 1.32 Vcell for urea electrolysis, which are decreases of 15 and 80 mV, respectively. The electron spin resonance, in situ Fourier transform infrared spectroscopy analysis and density functional theory calculations reveal that illumination led to the formation of Ni3+ active sites in a high-spin state, which strengthens the d-p orbital hybridization of Ni-N, hence facilitating the adsorption of urea. CâN cleavage of the *CONN intermediate is further inhibited, which promotes the oxidation of urea molecules via the active N2 pathway, thereby accelerating the UOR rate.
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Developing low-loading platinum-group-metal (PGM) catalysts is one of the key challenges in commercializing anion-exchange-membrane-fuel-cells (AEMFCs), especially for hydrogen oxidation reaction (HOR). Here, ruthenium-iridium nanoparticles being deposited on a Zn-N species-doped carbon carrier (Ru6Ir/Zn-N-C) are synthesized and used as an anodic catalyst for AEMFCs. Ru6Ir/Zn-N-C shows extremely high mass activity (5.87 A mgPGM -1) and exchange current density (0.92 mA cm-2), which is 15.1 and 3.9 times that of commercial Pt/C, respectively. Based on the Ru6Ir/Zn-N-C AEMFCs achieve a peak power density of 1.50 W cm-2, surpassing the state-of-the-art commercial PtRu catalysts and the power ratio of the normalized loading is 14.01 W mgPGM anode -1 or 5.89 W mgPGM -1 after decreasing the anode loading (87.49 µg cm-2) or the total PGM loading (0.111 mg cm-2), satisfying the US Department of Energy's PGM loading target. Moreover, the solvent and solute isotope separation method is used for the first time to reveal the kinetic process of HOR, which shows the reaction is influenced by the adsorption of H2O and OH-. The improvement of the hydrogen bond network connectivity of the electric double layer by adjusting the interfacial H2O structure together with the optimized HBE and OHBE is proposed to be responsible for the high HOR activity of Ru6Ir/Zn-N-C.
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The electrocatalytic urea oxidation reaction (UOR) provides a promising alternative to the oxygen evolution reaction (OER) for various renewable energy-related systems owing to its lower thermodynamic barriers. However, its optimization and commercial utilization were hampered due to a lack of mechanistic understanding. Here, we demonstrate a Ce-doped Ni3S2 catalyst supported on Ni foam (Ce-Ni3S2/NF) with superior activity toward UOR. The resultant Ce-Ni3S2/NF catalyst exhibits a lower Tafel slope of 20.3 mV dec-1, a higher current density of 100 mA cm-2 at 1.39 V versus RHE, and better durability than those for Ni3S2/NF. Based on in situ synchrotron radiation X-ray absorption spectroscopy, in situ Fourier transform infrared (FTIR), and in situ Raman spectroscopy, we observe the structural reconstruction of sulfide and identify the adsorbed intermediates during UOR. Density functional theory (DFT) calculations reveal that Ce can regulate the electronic structure of Ni through Ce(4f)-O(2p)-Ni(3d) orbital electronic coupling. The modulated Ni sites have weaker adsorption of carbonaceous intermediates, thus accelerating the UOR. This work provides a promising route for the design of high-activity UOR catalysts.
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Efficient and CO-tolerant catalysts for alkaline hydrogen oxidation (HOR) are vital to the commercial application of anion exchange membrane fuel cells (AEMFCs). Herein, a robust Ru-based catalyst (Ru/VOC) with ultrasmall Ru nanoparticles supported on carbon frameworks with atomically dispersed V-O species is prepared elaborately. The catalyst exhibits a remarkable mass activity of 3.44 mA µgPGM, which is 31.3 times that of Ru/C and even 4.7 times higher than that of Pt/C. Moreover, the Ru/VOC anode can achieve a peak power density (PPD) of 1.194 W cm-2, much superior to that of Ru/C anode and even better than that of Pt/C anode. In addition, the catalyst also exhibits superior stability and exceptional CO tolerance. Experimental results and density functional theory (DFT) calculations demonstrate that V-O species are ideal OH- adsorption sites, which allow Ru to release more sites for hydrogen adsorption. Furthermore, the electron transfer from Ru nanoparticles to the carbon substrate regulates the electronic structure of Ru, reducing the hydrogen binding energy (HBE) and the CO adsorption energy on Ru, thus boosting the alkaline HOR performance and CO tolerance of the catalyst. This is the first report that oxophilic single atoms distributed on carbon frameworks serve as OH- adsorption sites for efficient hydrogen oxidation, opening up new guidance for the elaborate design of high-activity catalysts for the alkaline HOR.
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Potassium-ion batteries (PIBs) have attracted more and more attention as viable alternatives to lithium-ion batteries (LIBs) due to the deficiency and uneven distribution of lithium resources. However, it is shown that potassium storage in some compounds through reaction or intercalation mechanisms cannot effectively improve the capacity and stability of anodes for PIBs. The unique anti-spinel structure of magnetite (Fe3 O4 ) is densely packed with thirty-two O atoms to form a face-centered cubic (fcc) unit cell with tetrahedral/octahedral vacancies in the O-closed packing structure, which can serve as K+ storage sites according to the density functional theory (DFT) calculation results. In this work, carbon-coated Fe3 O4 @C nanoparticles are prepared as high-performance anodes for PIBs, which exhibit high reversible capacity (638 mAh g-1 at 0.05 A g-1 ) and hyper stable cycling performance at ultrahigh current density (150 mAh g-1 after 9000 cycles at 10 A g-1 ). In situ XRD, ex-situ Fe K-edge XAFS, and DFT calculations confirm the storage of K+ in tetrahedral/octahedral vacancies.
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This article briefly describes the imaging performance standards of the kilovolt X-ray image guidance system used in radiotherapy, analyzes the main aspects that should be considered in the image quality of X-IGRT system, and focuses on parameters that should be considered in the imaging performance evaluation criteria of the CBCT X-IGRT. The purpose is to sort out the imaging performance evaluation standards of kilovolt X-IGRT system, clarify the image quality requirements of X-IGRT equipment, and reach a consensus when evaluating the imaging performance of X-IGRT system.
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Radioterapia Guiada por Imagem , Radioterapia de Intensidade Modulada , Tomografia Computadorizada de Feixe Cônico Espiral , Planejamento da Radioterapia Assistida por Computador/métodos , Tomografia Computadorizada de Feixe Cônico/métodos , Radioterapia de Intensidade Modulada/métodos , Radioterapia Guiada por Imagem/métodosRESUMO
The Decapentaplegic (Dpp) gene, which belongs to the TGF-ß superfamily, is involved in multiple developmental processes in eukaryotic species. In this study, we firstly identified and characterized Dpp from Macrobrachium nipponense. Its full-length open reading frame (ORF) cDNA was 1332 bp, encoding 443 amino acids. The putative MnDpp protein contained a signal peptide, a TGF-ß propeptide region and a TGF-ß domain. Its TGF-ß domain was highly conserved from vertebrates to invertebrates, and exhibited highly similarity to Dpp derived from Bombyx mori. qRT-PCR analysis suggested that MnDpp expressed in all tested tissues and responded to both bacterial and virus pathogens, indicating MnDpp was involved in the innate immune response of M. nipponense. Knockdown of MnDppin vivo significantly increased bacteria growth and markedly decreased the expressions of NF-κB signaling genes including dorsal, relish, TAK1, TAB1, Ikkß and Ikkε as well as antimicrobial peptides (AMPs) including ALF2, ALF3, ALF4, ALF5, Cru1 and Cru2. Moreover, in vitro overexpression of MnDpp protein in HEK293T cells further demonstrated that it exerted antibacterial immune response by activation of NF-κB signaling cascade. In summary, these results indicated that MnDpp played an important role in the innate immunity in M. nipponense by modulating NF-κB signaling pathway, which might provide new insights about Dpp in crustaceans and paved the way for a better understanding of the crustacean innate immune system.
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Proteínas de Artrópodes/imunologia , NF-kappa B/imunologia , Palaemonidae/imunologia , Fator de Crescimento Transformador beta/imunologia , Aeromonas hydrophila , Sequência de Aminoácidos , Animais , Proteínas de Artrópodes/genética , Sequência de Bases , Clonagem Molecular , Infecções por Vírus de DNA/imunologia , Infecções por Vírus de DNA/veterinária , Infecções por Bactérias Gram-Negativas/imunologia , Infecções por Bactérias Gram-Negativas/veterinária , Células HEK293 , Humanos , Palaemonidae/genética , Palaemonidae/microbiologia , Filogenia , Fator de Crescimento Transformador beta/genética , Vírus da Síndrome da Mancha Branca 1RESUMO
Buprenorphine, a maintenance drug for heroin addicts, exerts its pharmacological function via κ- (KOP), µ-opioid (MOP) and nociceptin/opioid receptor-like 1 (NOP) receptors. Previously, we investigated its effects in an in vitro model expressing human MOP and NOP receptors individually or simultaneously (MOP, NOP, and MOP+NOP) in human embryonic kidney 293 cells. Here, we expanded this cell model by expressing human KOP, MOP and NOP receptors individually or simultaneously (KOP, KOP+MOP, KOP+NOP and KOP+MOP+NOP). Radioligand binding with tritium-labelled diprenorphine confirmed the expression of KOP receptors. Immunoblotting and immunocytochemistry indicated that the expressed KOP, MOP and NOP receptors are N-linked glycoproteins and colocalized in cytoplasmic compartments. Acute application of the opioid receptor agonists- U-69593, DAMGO and nociceptin- inhibited adenylate cyclase (AC) activity in cells expressing KOP, MOP and NOP receptors respectively. Buprenorphine, when applied acutely, inhibited AC activity to ~90% in cells expressing KOP+MOP+NOP receptors. Chronic exposure to buprenorphine induced concentration-dependent AC superactivation in cells expressing KOP+NOP receptors, and the level of this superactivation was even higher in KOP+MOP+NOP-expressing cells. Our study demonstrated that MOP receptor could enhance AC regulation in the presence of coexpressed KOP and NOP receptors, and NOP receptor is essential for concentration-dependent AC superactivation elicited by chronic buprenorphine exposure.
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Adenilil Ciclases/metabolismo , Analgésicos Opioides/farmacologia , Buprenorfina/farmacologia , Receptores Opioides kappa/biossíntese , Receptores Opioides mu/biossíntese , Inibidores de Adenilil Ciclases/farmacologia , Relação Dose-Resposta a Droga , Ativação Enzimática/efeitos dos fármacos , Células HEK293 , Humanos , Técnicas ImunológicasRESUMO
VCAM-1 (CD106), a transmembrane glycoprotein, was first reported to play an important role in leukocyte adhesion, leukocyte transendothelial migration and cell activation by binding to integrin VLA-1 (α4ß1). In the present study, we observed that VCAM-1 expression can be induced in many breast cancer epithelial cells by cytokine stimulation in vitro and its up-regulation directly correlated with advanced clinical breast cancer stage. We found that VCAM-1 over-expression in the NMuMG breast epithelial cells controls the epithelial and mesenchymal transition (EMT) program to increase cell motility rates and promote chemoresistance to doxorubicin and cisplatin in vitro. Conversely, in the established MDAMB231 metastatic breast cancer cell line, we confirmed that knockdown of endogenous VCAM-1 expression reduced cell proliferation and inhibited TGFß1 or IL-6 mediated cell migration, and increased chemosensitivity. Furthermore, we demonstrated that knockdown of endogenous VCAM-1 expression in MDAMB231 cells reduced tumor formation in a SCID xenograft mouse model. Signaling studies showed that VCAM-1 physically associates with CD44 and enhances CD44 and ABCG2 expression. Our findings uncover the possible mechanism of VCAM-1 activation facilitating breast cancer progression, and suggest that targeting VCAM-1 is an attractive strategy for therapeutic intervention.
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Neoplasias da Mama/genética , Regulação Neoplásica da Expressão Gênica/genética , Receptores de Hialuronatos/genética , Molécula 1 de Adesão de Célula Vascular/genética , Adulto , Animais , Antineoplásicos/farmacologia , Western Blotting , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Linhagem Celular , Linhagem Celular Tumoral , Movimento Celular/genética , Cisplatino/farmacologia , Citocinas/farmacologia , Doxorrubicina/farmacologia , Resistencia a Medicamentos Antineoplásicos/genética , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Células HEK293 , Humanos , Receptores de Hialuronatos/metabolismo , Camundongos SCID , Pessoa de Meia-Idade , Ligação Proteica , Interferência de RNA , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transplante Heterólogo , Carga Tumoral/genética , Molécula 1 de Adesão de Célula Vascular/metabolismoRESUMO
Improving the catalytic efficiency of platinum group metal-free (PGM-free) catalysts for the sluggish alkaline hydrogen oxidation reaction (HOR) is crucial to the anion exchange membrane fuel cell. Recently, numerous Ni-based heterostructures have been designed based on bifunctional theory to enhance HOR activity by optimizing the binding energy of both H* and OH*; however, their activities are still far inferior to those of PGM catalysts. Indeed, the long transfer pathway for intermediates between different active sites in such heterostructures has rarely been investigated, which could be the reason for the bottleneck. Here, we design a Ni/MoOxHy heterostructure catalyst to promote H* migration from the Ni side to the interface for alkaline HOR via the hydrogen spillover effect. In situ X-ray absorption fine structure, Raman characterizations, H/D kinetic isotope effects, and theoretical calculations have proven facile H* migration from the Ni side to the interface, which further reacts with OH* on the MoOxHy surface. Besides, the hydrogen spillover effect is also beneficial for the preservation of the metallic phase of Ni during the reaction. The catalyst exhibits a high activity with Jk,m of 58.5 mA mgNi-1 and j0,s of 42 µA cmNi-2, which is among the best PGM-free catalysts and is even comparable to some PGM catalysts. It also shows the highest power density (511 mW cm-2) as a PGM-free anode when assembled into fuel cells under moderate back pressure. These findings prove that in addition to optimizing electrophilicity and oxophilicity for active sites, we could also improve the HOR activity from the transfer pathway for intermediates, which provides insight into the design of other efficient HOR catalysts.
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The electrochemical reduction of CO2 to HCOOH is considered one of the most appealing routes to alleviate the energy crisis and close the anthropogenic CO2 cycle. However, it remains challenging to develop electrocatalysts with high activity and selectivity towards HCOOH in a wide potential window. In this regard, Ag/Bi2O2CO3 was prepared by an in situ electrochemical transformation from Ag/Bi2O3. The Ag/Bi2O2CO3 catalyst achieves a faradaic efficiency (FE) of over 90% for HCOOH in a wide potential window between -0.8 V and -1.3 V versus the reversible hydrogen electrode (RHE). Moreover, a maximum FE of 95.8% and a current density of 15.3 mA cm-2 were achieved at a low applied potential of -1.1 V. Density functional theory (DFT) calculations prove that the high catalytic activity of Ag/Bi2O2CO3 is ascribed to the fact that Ag can regulate the electronic structure of Bi, thus facilitating the adsorption of *OCHO and hindering the adsorption of *COOH. This work expands the in situ electrochemical derivatization strategy for the preparation of electrocatalysts.
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A series of bifunctional compounds have been discovered for their dual functionality as MER/AXL inhibitors and immune modulators. The furanopyrimidine scaffold, renowned for its suitability in kinase inhibitor discovery, offers at least three distinct pharmacophore access points. Insights from molecular modeling studies guided hit-to-lead optimization, which revealed that the 1,3-diketone side chain hybridized with furanopyrimidine scaffold that respectively combined amino-type substituent and 1H-pyrazol-4-yl substituent on the top and bottom of the aryl regions to produce 22 and 33, exhibiting potent antitumor activities in various syngeneic and xenograft models. More importantly, 33 demonstrated remarkable immune-modulating activity by upregulating the expression of total T-cells, cytotoxic CD8+ T-cells, and helper CD4+ T-cells in the spleen. These findings underscored the bifunctional capabilities of 33 (BPR5K230) with excellent oral bioavailability (F = 54.6%), inhibiting both MER and AXL while modulating the tumor microenvironment and highlighting its diverse applicability for further studies to advance its therapeutic potential.
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Antineoplásicos , Receptor Tirosina Quinase Axl , Inibidores de Proteínas Quinases , Proteínas Proto-Oncogênicas , Receptores Proteína Tirosina Quinases , Microambiente Tumoral , c-Mer Tirosina Quinase , Animais , Microambiente Tumoral/efeitos dos fármacos , Humanos , Inibidores de Proteínas Quinases/farmacologia , Inibidores de Proteínas Quinases/química , Inibidores de Proteínas Quinases/uso terapêutico , Inibidores de Proteínas Quinases/síntese química , Antineoplásicos/farmacologia , Antineoplásicos/química , Antineoplásicos/síntese química , Antineoplásicos/uso terapêutico , Receptores Proteína Tirosina Quinases/antagonistas & inibidores , Receptores Proteína Tirosina Quinases/metabolismo , Proteínas Proto-Oncogênicas/antagonistas & inibidores , Proteínas Proto-Oncogênicas/metabolismo , c-Mer Tirosina Quinase/antagonistas & inibidores , c-Mer Tirosina Quinase/metabolismo , Camundongos , Linhagem Celular Tumoral , Relação Estrutura-Atividade , Descoberta de Drogas , Bibliotecas de Moléculas Pequenas/farmacologia , Bibliotecas de Moléculas Pequenas/química , Bibliotecas de Moléculas Pequenas/síntese química , Feminino , Ensaios Antitumorais Modelo de Xenoenxerto , Camundongos Endogâmicos BALB C , Proliferação de Células/efeitos dos fármacosRESUMO
Oxidative stress is highly prevalent in maintenance hemodialysis patients and increases the risk of cardiovascular morbidity and mortality. Silymarin (SM) is a natural compound extracted from plants, and has been shown to have pharmacological effects such as antioxidant, anti-inflammatory, cytoprotective, and anti-nephrotoxicity. SM-modified polysulfone (PSF) hemodialysis membranes were prepared by an immersion-precipitation phase transition method. The experimental results showed that the modified membranes effectively scavenged free radicals, significantly inhibited lipid peroxidation, and had good antioxidant stability (60 days). The PSF/SM antioxidant membranes (H-3) had no pro-inflammatory effect, which was confirmed by the result of anti-M1 macrophage polarization. Furthermore, the hemolysis rate (2%), blood cell deformation (3.7%), and inhibition of erythrocyte and platelet adhesion were improved by the SM-modified PSF membranes. All the results suggest that PSF/SM blended hollow fiber membranes are promising for application in hemodialysis membranes to improve oxidative stress status and reduce inflammation and complications in patients.
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Antioxidantes , Silimarina , Humanos , Antioxidantes/farmacologia , Materiais Biocompatíveis/farmacologia , Macrófagos , Membranas ArtificiaisRESUMO
Electrochemical carbon dioxide reduction reaction (CO2RR) is an effective approach to capture CO2 and convert it into value-added chemicals and fuels, thereby reducing excess CO2 emissions. Recent reports have shown that copper-based catalysts exhibit excellent performance in converting CO2 into multi-carbon compounds and hydrocarbons. However, theselectivityto the couplingproductsispoor. Therefore, tuningCO2-reductionselectivitytoward C2+productsover Cu-based catalyst is one of the most important issues in CO2RR. Herein, we prepare a nanosheet catalyst with interfaces of Cu0/Cu+. The catalyst achieves Faraday efficiency (FE) of C2+ over 50% in a wide potential window between - 1.2 V to - 1.5 V versus reversible hydrogen electrode (vs. RHE). Moreover, the catalyst exhibits maximum FE of 44.5% and 58.9% towards C2H4 and C2+, with a partial current density of 10.5 mA cm-2 at - 1.4 V. Density functional theory (DFT) calculations show that the interface of Cu0/Cu+ facilitates CC coupling to form C2+ products, while inhibits CO2conversion toC1products.
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The biomechanical changes following meniscal tears and surgery could lead to or accelerate the occurrence of osteoarthritis. The aim of this study was to investigate the biomechanical effects of horizontal meniscal tears and different resection strategies on a rabbit knee joint by finite element analysis and to provide reference for animal experiments and clinical research. Magnetic resonance images of a male rabbit knee joint were used to establish a finite element model with intact menisci under resting state. A medial meniscal horizontal tear was set involving 2/3 width of a meniscus. Seven models were finally established, including intact medial meniscus (IMM), horizontal tear of the medial meniscus (HTMM), superior leaf partial meniscectomy (SLPM), inferior leaf partial meniscectomy (ILPM), double-leaf partial meniscectomy (DLPM), subtotal meniscectomy (STM), and total meniscectomy (TTM). The axial load transmitted from femoral cartilage to menisci and tibial cartilage, the maximum von Mises stress and the maximum contact pressure on the menisci and cartilages, the contact area between cartilage to menisci and cartilage to cartilage, and absolute value of the meniscal displacement were analyzed and evaluated. The results showed that the HTMM had little effect on the medial tibial cartilage. After the HTMM, the axial load, maximum von Mises stress and maximum contact pressure on the medial tibial cartilage increased 1.6%, 1.2%, and 1.4%, compared with the IMM. Among different meniscectomy strategies, the axial load and the maximum von Mises stress on the medial menisci varied greatly. After the HTMM, SLPM, ILPM, DLPM, and STM, the axial load on medial menisci decreased 11.4%, 42.2%, 35.4% 48.7%, and 97.0%, respectively; the maximum von Mises stress on medial menisci increased 53.9%, 62.6%, 156.5%, and 65.5%, respectively, and the STM decreased 57.8%, compared to IMM. The radial displacement of the middle body of the medial meniscal was larger than any other part in all the models. The HTMM led to few biomechanical changes in the rabbit knee joint. The SLPM showed minimal effect on joint stress among all resection strategies. It is recommended to preserve the posterior root and the remaining peripheral edge of the meniscus during surgery for an HTMM.
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A series of novel ferulic acid derivatives were designed and synthesized, and the twenty-one compounds were evaluated for their antiviral activities against Respiratory syncytial virus (RSV), herpes simplex virus type 1 (HSV-1), and enterovirus type 71 (EV71). These derivatives with the core structure of diphenyl acrylic acids had cis-trans isomers, which were confirmed by 1H NMR, HPLC, and UV-vis spectra for the first time. The A5 had a selective effect against RSV but no work on herpes simplex virus type 1 and enterovirus type 71, which showed a therapeutic index (TI) of 32 and was significantly better than ferulic acid. The A5 had no scavenging effect on free radicals, but the A2 as the degradation of A5 showed an obvious scavenging effect on DPPH· and ABTS+·. In addition, the A5 had no toxicity to endothelial cells and even showed a proliferative effect. Therefore, the A5 is worth further optimizing its structure as a lead compound and investigating the mechanism of inhibiting Respiratory syncytial virus.
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Currently, there is a significant unmet need for novel analgesics with fewer side effects. In this study, we carried out structural modification of a hit compound previously identified in an artificial-intelligence (AI) virtual screening and discovered the potent analgesic, benzo[b]thiophene-2-carboxamide analog (compound 25) with new structural scaffold. We investigated the signaling pathways of opioid receptors mediated by compound 25, and found this racemic compound activated mu-opioid receptor through the cyclic adenosine monophosphate (cAMP) and ß-arrestin-2-mediated pathways with strong potency and efficacy, and accompanying nociceptin-orphanin FQ opioid peptide and delta-opioid receptors through the cAMP pathway with weak potencies. Compound 25 elicited potent antinociception in thermal-stimulated pain (ED50 value of 127.1 ± 34.65 µg/kg) and inflammatory-induced allodynia models with less gastrointestinal transit inhibition and antinociceptive tolerance than morphine. Overall, this study revealed a novel analgesic with reduced risks of side effects.
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Analgésicos Opioides , Tiofenos , Humanos , Tiofenos/farmacologia , Tiofenos/uso terapêutico , Analgésicos Opioides/efeitos adversos , Receptores Opioides mu/agonistas , Receptores Opioides/agonistas , Peptídeos Opioides , Morfina/farmacologia , Analgésicos/farmacologia , Analgésicos/uso terapêutico , Analgésicos/química , Constipação Intestinal/induzido quimicamente , Constipação Intestinal/tratamento farmacológicoRESUMO
The four-and-a-half LIM-only protein family of transcription co-factors participates in various cellular processes, such as cell proliferation, cell differentiation, apoptosis, cell adhesion, migration, transcription and signal transduction. However, the knowledge of the structural characteristics and immune functions of its ancestor Lmpt, which contains six LIM domains at the C-terminus and a PET domain at the N-terminus, is limited in invertebrates, especially in crustaceans. In the present study, a novel Lmpt from oriental river prawn (Macrobrachium nipponense) was identified, and its role in the immune response was investigated. Its full-length cDNA sequence was 6407 bp, which contained a 2595 bp ORF encoding 865 amino acids, exhibiting high similarity to the structure of Lmpt derived from other invertebrates. Tissue distribution analysis revealed that MnLmpt was widely expressed in all examined tissues, and high expression levels were observed in muscle, heart and intestine in M. nipponense. After experimental challenges with bacteria and virus, the transcription levels of MnLmpt significantly fluctuated in gill and hepatopancreas, indicating that it might play a role in the innate immune response in M. nipponense. Silencing of MnLmpt by dsRNA injection in vivo could promote bacterial growth, suggesting that MnLmpt exerted an antibacterial immune function in prawn. Immunocytochemistry assay results demonstrated that MnLmpt was able to translocate from the cytoplasm to the nucleus after being stimulated with pathogens. The expression levels of NF-κB signalling cascade members, such as dorsal, relish, TAK1, TAB1, Ikkß, and Ikkε, and AMPs, including ALF4, Cru1, and Cru2, exhibited significant downregulation in the MnLmpt silenced group. Similarly, dual-luciferase reporter assays also demonstrated that MnLmpt could stimulate an NF-κB signalling cascade. Meanwhile, all of the LIM domains of MnLmpt could trigger NF-κB signalling; however, their cumulative effect on NF-κB promoter activation was hardly observed. These results showed that MnLmpt might play a crucial role in the innate immune response in M. nipponense, and these findings paved the way for a better understanding of the immune system in crustacean species.
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Proteínas com Domínio LIM/imunologia , NF-kappa B/metabolismo , Palaemonidae/imunologia , Transporte Ativo do Núcleo Celular , Aeromonas hydrophila/fisiologia , Sequência de Aminoácidos , Animais , Proteínas de Artrópodes/genética , Proteínas de Artrópodes/imunologia , Proteínas de Artrópodes/metabolismo , Núcleo Celular/metabolismo , Clonagem Molecular , Perfilação da Expressão Gênica , Regulação da Expressão Gênica , Imunidade Inata/genética , Proteínas com Domínio LIM/genética , Proteínas com Domínio LIM/metabolismo , NF-kappa B/genética , Filogenia , Regiões Promotoras Genéticas , Alinhamento de Sequência , Transdução de Sinais , Distribuição TecidualRESUMO
Rare oncogenic NTRK gene fusions result in uncontrolled TRK signaling leading to various adult and pediatric solid tumors. Based on the architecture of our multi-targeted clinical candidate BPR1K871 (10), we designed and synthesized a series of quinazoline compounds as selective and orally bioavailable type II TRK inhibitors. Property-driven and lead optimization strategies informed by structure-activity relationship studies led to the identification of 39, which showed higher (about 15-fold) selectivity for TRKA over AURA and AURB, as well as potent cellular activity (IC50 = 56.4 nM) against the KM12 human colorectal cancer cell line. 39 also displayed good AUC and oral bioavailability (F = 27%), excellent in vivo efficacy (TGI = 64%) in a KM12 xenograft model, and broad-spectrum anti-TRK mutant potency (IC50 = 3.74-151.4 nM), especially in the double-mutant TRKA enzymatic assays. 39 is therefore proposed for further development as a next-generation, selective, and orally-administered type II TRK inhibitor.