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Fluorine owing to its inherently high electronegativity exhibits charge delocalization and ion dissociation capabilities; as a result, there has been an influx of research studies focused on the utilization of fluorides to optimize solid electrolyte interfaces and provide dynamic protection of electrodes to regulate the reaction and function performance of batteries. Nonetheless, the shuttle effect and the sluggish redox reaction kinetics emphasize the potential bottlenecks of lithium-sulfur batteries. Whether fluorine modulation regulate the reaction process of Li-S chemistry? Here, the TiOF/Ti3C2 MXene nanoribbons with a tailored F distribution were constructed via an NH4F fluorinated method. Relying on in situ characterizations and electrochemical analysis, the F activates the catalysis function of Ti metal atoms in the consecutive redox reaction. The positive charge of Ti metal sites is increased due to the formation of O-Ti-F bonds based on the Lewis acid-base mechanism, which contributes to the adsorption of polysulfides, provides more nucleation sites and promotes the cleavage of S-S bonds. This facilitates the deposition of Li2S at lower overpotentials. Additionally, fluorine has the capacity to capture electrons originating from Li2S dissolution due to charge compensation mechanisms. The fluorine modulation strategy holds the promise of guiding the construction of fluorine-based catalysts and facilitating the seamless integration of multiple consecutive heterogeneous catalytic processes.
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BACKGROUND: Mazabraud's syndrome (MS) is a rare and slowly progressive benign disease characterized by the concurrent presence of fibrous dysplasia of bone and intramuscular myxoma, and is thought to be associated with mutations of the GNAS gene. To date, only about 100 cases of MS have been reported in the literature, but its standard treatment strategy remains unclear. CASE SUMMARY: We report two cases of MS in young women who underwent different treatments based on their symptoms and disease manifestations. The first patient, aged 37, received internal fixation and intravenous bisphosphonate for a pathological fracture of the right femoral neck, excision of a right vastus medialis myxoma was subsequently performed for pain control, and asymptomatic psoas myxomas were monitored without surgery. Genetic testing confirmed a GNAS gene mutation in this patient. The second patient, aged 24, underwent right vastus intermedius muscle myxoma resection, and conservative treatment for fibrous dysplasia of the ilium. These patients were followed-up for 17 months and 3 years, respectively, and are now in a stable condition. CONCLUSION: Various treatments have been selected for MS patients who suffer different symptoms. The main treatment for myxomas is surgical resection, while fibrous dysplasia is selectively treated if the patient experiences pathological fracture or severe pain. However, given the documented instances of malignant transformation of fibrous dysplasia in individuals with MS, close follow-up is necessary.
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Lhx3 is a LIM-homeodomain transcription factor that affects body size in mammals by regulating the secretion of pituitary hormones. Akita, Shiba Inu, and Mame Shiba Inu dogs are Japanese native dog breeds that have different body sizes. To determine whether Lhx3 plays a role in the differing body sizes of these three dog breeds, we sequenced the Lhx3 gene in the three breeds, which led to the identification of an SNP in codon 280 (S280N) associated with body size. The allele frequency at this SNP differed significantly between the large Akita and the two kinds of smaller Shiba dogs. To validate the function of this SNP on body size, we introduced this change into the Lhx3 gene of mice. Homozygous mutant mice (S279N+/+) were found to have significantly increased body lengths and weights compared to heterozygous mutant (S279N+/-) and wild-type (S279N-/-) mice several weeks after weaning. These results demonstrate that a nonsynonymous substitution in Lhx3 plays an important role in regulating body size in mammals.
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Tamaño Corporal , Proteínas con Homeodominio LIM , Polimorfismo de Nucleótido Simple , Factores de Transcripción , Animales , Proteínas con Homeodominio LIM/genética , Proteínas con Homeodominio LIM/metabolismo , Factores de Transcripción/genética , Ratones , Tamaño Corporal/genética , Perros/genética , Frecuencia de los Genes , Masculino , FemeninoRESUMEN
BACKGROUND: Currently, no effective measures are available to predict the curative efficacy of small-cell lung cancer (SCLC) chemotherapy. We expect to develop a method for effectively predicting the SCLC chemotherapy efficacy and prognosis in clinical practice in order to offer more pertinent therapeutic protocols for individual patients. METHODS: We adopted matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS) and ClinPro Tools system to detect serum samples from 154 SCLC patients with different curative efficacy of standard chemotherapy and analyze the different peptides/proteins of SCLC patients to discover predictive tumor markers related to chemotherapy efficacy. Ten peptide/protein peaks were significantly different in the two groups. RESULTS: A genetic algorithm model consisting of four peptides/proteins was developed from the training group to separate patients with different chemotherapy efficacies. Among them, three peptides/proteins (m/z 3323.35, 6649.03 and 6451.08) showed high expression in the disease progression group, whereas the peptide/protein at m/z 4283.18 was highly expressed in the disease response group. The classifier exhibited an accuracy of 91.4% (53/58) in the validation group. The survival analysis showed that the median progression-free survival (PFS) of 30 SCLC patients in disease response group was 9.0 months; in 28 cases in disease progression group, the median PFS was 3.0 months, a statistically significant difference (χ2 = 46.98, P < 0.001). The median overall survival (OS) of the two groups was 13.0 months and 7.0 months, a statistically significant difference (χ2 = 40.64, P < 0.001). CONCLUSIONS: These peptides/proteins may be used as potential biological markers for prediction of the curative efficacy and prognosis for SCLC patients treated with standard regimen chemotherapy.
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It has been known that plastics with undegradability and long half-times have caused serious environmental and ecological issues. Considering the devastating effects, the development of efficient plastic upcycling technologies with low energy consumption is absolutely imperative. Catalytic hydrogenolysis of single-use polyethylene over Ru-based catalysts to produce high-quality liquid fuel has been one of the current top priority strategies, but it is restricted by some tough challenges, such as the tendency towards methanation resulting from terminal C-C cleavage. Herein, we introduced Ru nanoparticles supported on hollow ZSM-5 zeolite (Ru/H-ZSM-5) for hydrocracking of high-density polyethylene (HDPE) under mild reaction conditions. The implication of experimental results is that the 1Ru/H-ZSM-5 (~1â wt % Ru) acted as an effective and reusable bifunctional catalyst providing higher conversion rate (82.53 %) and liquid fuel (C5-C21) yield (62.87 %). Detailed characterization demonstrated that the optimal performance in hydrocracking of PE could be attributed to the moderate acidity and appropriate positively charged Ru species resulting from the metal-zeolite interaction. This work proposes a promising catalyst for plastic upcycling and reveals its structure-performance relationship, which has guiding significance for catalyst design to improve the yield of high-value liquid fuels.
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Interfacial interaction dictates the overall catalytic performance and catalytic behavior rules of the composite catalyst. However, understanding of interfacial active sites at the microscopic scale is still limited. Importantly, identifying the dynamic action mechanism of the "real" active site at the interface necessitates nanoscale, high spatial-time-resolved complementary-operando techniques. In this work, a Co3O4 homojunction with a well-defined interface effect is developed as a model system to explore the spatial-correlation dynamic response of the interface toward oxygen evolution reaction. Quasi in situ scanning transmission electron microscopy-electron energy-loss spectroscopy with high spatial resolution visually confirms the size characteristics of the interface effect in the spatial dimension, showing that the activation of active sites originates from strong interfacial electron interactions at a scale of 3 nm. Multiple time-resolved operando spectroscopy techniques explicitly capture dynamic changes in the adsorption behavior for key reaction intermediates. Combined with density functional theory calculations, we reveal that the dynamic adjustment of multiple adsorption configurations of intermediates by highly activated active sites at the interface facilitates the O-O coupling and *OOH deprotonation processes. The dual dynamic regulation mechanism accelerates the kinetics of oxygen evolution and serves as a pivotal factor in promoting the oxygen evolution activity of the composite structure. The resulting composite catalyst (Co-B@Co3O4/Co3O4 NSs) exhibits an approximately 70-fold turnover frequency and 20-fold mass activity than the monomer structure (Co3O4 NSs) and leads to significant activity (η10 â¼257 mV). The visual complementary analysis of multimodal operando/in situ techniques provides us with a powerful platform to advance our fundamental understanding of interfacial structure-activity relationships in composite structured catalysts.
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The diagnosis of cancer based on gene expression profile data has attracted extensive attention in the field of biomedical science. This type of data usually has the characteristics of high dimensionality and noise. In this paper, a hybrid gene selection method based on clustering and sparse learning is proposed to choose the key genes with high precision. We first propose a filter method, which combines the k-means clustering algorithm and signal-to-noise ratio ranking method, and then, a weighted gene co-expression network has been applied to the reduced data set to identify modules corresponding to biological pathways. Moreover, we choose the key genes by using group bridge and sparse group lasso as wrapper methods. Finally, we conduct some numerical experiments on six cancer datasets. The numerical results show that our proposed method has achieved good performance in gene selection and cancer classification.
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Algoritmos , Neoplasias , Humanos , Redes Reguladoras de Genes , Neoplasias/genética , Neoplasias/metabolismo , Análisis por ConglomeradosRESUMEN
Introduction: The relationship between the expression of opioid-associated receptors and cancer outcomes is complex and varies among studies. Methods: This study focused on six opioid-related receptors (OPRM1, OPRD1, OPRK1, OPRL1, OGFR, and TLR4) and their impact on cancer patient survival. Bioinformatics analysis was conducted on 33 cancer types from The Cancer Genome Atlas database to examine their expression, clinical correlations, mechanisms in the tumor microenvironment, and potential for immunotherapy. Due to significantly lower expression of OPRM1, OPRD1, and OPRK1 compared to OGFR and TLR4, the analysis concentrated on the latter two genes. Results: OGFR was highly expressed in 16 tumor types, while TLR4 showed low expression in 13. Validation from external samples, the Gene Expression Omnibus, and the Human Protein Atlas supported these findings. The diagnostic value of these two genes was demonstrated using the Genotype-Tissue Expression database. Univariate Cox regression models and Kaplan-Meier curves confirmed OGFR's impact on prognosis in a cancer type-specific manner, while high TLR4 expression was associated with a favorable prognosis. Analysis of the tumor microenvironment using a deconvolution algorithm linked OGFR to CD8+ T cells and TLR4 to macrophages. Single-cell datasets further validated this correlation. In 25 immune checkpoint blockade treatment cohorts, TLR4 expression showed promise as an immunotherapy efficacy predictor in non-small cell lung cancer, urothelial carcinoma, and melanoma. Conclusion: In a pan-cancer analysis of 33 tissues, OGFR was consistently highly expressed, while TLR4 had low expression. Both genes have diagnostic and prognostic significance and are linked to immune cells in the tumor microenvironment. TLR4 has potential as an immunotherapeutic response marker.
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To clarify the photosynthetic mechanism contributing to the enhancement of intercropping advantages through co-ridge intercropping of maize and peanut, we conducted a field randomized block experiment under two phosphorus levels of 0(P0) and 180 kg P2O5·hm-2(P180) with flat intercropping of maize and peanut (FIC) as the control. We analyzed the effects of co-ridge intercropping of maize and peanut (RIC) and groove-ridge intercropping of maize and peanut (GIC) on crop leaf area index (LAI), SPAD values, CO2 carboxylation ability, photosystems coordination (ΦPSâ /PSâ ¡), and intercropping advantage of yield. The results showed that RIC significantly increased SPAD value at the silking stage of intercropping maize, and significantly improved the apparent quantum yield of photosynthesis (AQY), maximum electron transfer rate (Jmax), maximum rate of Rubisco carboxylation (Vc,max), net photosynthetic rate at the CO2 saturation (Amax) and ΦPSâ /PSâ ¡ of intercropping maize compared with those of FIC and GIC at silking stage and milking stage, but reduced the ratio of variable fluorescence Fk to amplitude Fj-Fo(Wk) and the ratio of variable fluorescence Fj to amplitude Fp-Fo(Vj) of the functional leaf photosystem â ¡ (PSâ ¡) at the milking stage of maize. There were no significant differences in these parameters between FIC and GIC. Compared with FIC, both RIC and GIC increased LAI of intercropping peanut at late growth stage and SPAD value at pod setting stage, significantly improved Vc,max, Amax, and ΦPSâ /PSâ ¡, and reduced Wk and Vj values of intercropping peanut functional leaves at pod expanding stage. The difference in these parameters between RIC and GIC were not significant. The land equivalent ratio and intercropping advantages of RIC were higher than those of FIC and GIC. Phosphorus application could further promote Vc,max, Jmax, Amax and ΦPSâ /PSâ ¡ of intercropping maize and peanut, and significantly improve yield advantages of intercropping. The findings indicated that co-ridge intercropping could enhance CO2 carboxylation and fixation by improving photosynthetic electron transport and pho-tosystems coordination, improve the photosynthetic rate of functional leaves of maize and peanut, thus increase crop yield and intercropping advantages.
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Arachis , Zea mays , Dióxido de Carbono , Agricultura/métodos , Fotosíntesis , FósforoRESUMEN
The interface structure of supported catalysts plays a significant role in the strong metal-support interactions (SMSI). However, it remains limited on interpreting interface structures, thus affecting the understanding of SMSI origin and impact on catalytic performance. Herein, electronic energy loss spectroscopy was adopted to characterize the interface microstructures of Pt/TiO2 materials. After high-temperature reduction processing, it was observed that the coating on the surface of the Pt metal particles was TiOx. Then, based on Gaussian function fitting, an effective and valid method was established for quantitative analysis on Ti L edge loss spectrum. This method allowed us to accurately determine the stoichiometric number of TiOx phases. In order to probe the classical phenomenon of strong metal-support interactions in more detail, we also discussed and analyzed the origin of TiOx and its effect on the electronic structure of the material using density functional theory calculations. The structure of surfaces and interfaces as well as the chemical evolution of supported catalysts on a microscale have been revealed, thereby providing a new analysis method and research perspectives for the future study of metal-support interactions.
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Fish skin is the first barrier against external invasion, and also an important interface for communication between males and females during reproduction. Nonetheless, sexual dimorphism in the physiology of fish skins is still poorly understood. Herein, transcriptomes of skin were comparatively analysed between males and females in spinyhead croaker, Collichthys lucidus. Totally, 170 differentially expressed genes (DEG) were detected, including 79 female-biased genes and 91 male-biased genes. Gene ontology (GO) annotation items of the DEGs were mainly enriched in biological process items (86.2%), including regulation of biological processes, responses to chemical and biological stimuli, transport and secretion, movement, immune response, tissue development, etc. In KEGG (Kyoto Encyclopedia of Genes and Genomes) pathway enrichment analysis, the male-biased genes were enriched in pathways including those related to immunity such as the TNF signalling pathway and IL-17 signalling pathway, whereas the female-biased genes were enriched in pathways including those related to female steroids such as ovarian steroidogenesis and oestrogen signalling pathway. In addition, odf3 was found to be a male-specific expression gene, being a candidate marker for phenotypic sex. Thus, the sexual difference in gene expression in fish skin in spawning season was uncovered by transcriptome analysis for the first time, providing new insights into sexual dimorphism in the physiology and functions of fish skin.
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Perciformes , Transcriptoma , Femenino , Masculino , Animales , Sexismo , Perfilación de la Expresión Génica , Perciformes/genética , PielRESUMEN
Lithium-sulfur (Li-S) batteries, as one of the new energy storage batteries, show immense potential due to their high theoretical specific capacity and theoretical energy density. However, there are still some problems to be solved, among which the shuttle effect of lithium polysulfides is one extremely serious issue with respect to the industrial application of Li-S batteries. Rational design of electrode materials with effective catalytic conversion ability is an effective route to accelerate the conversion of lithium polysulfides (LiPSs). Herein, considering the adsorption and catalysis of LiPSs, CoOx nanoparticles (NPs) loaded on carbon sphere composites (CoOx/CS) were designed and constructed as cathode materials. The CoOx NPs obtained, with ultralow weight ratio and uniform distribution, consist of CoO, Co3O4, and metallic Co. The polar CoO and Co3O4 enable chemical adsorption towards LiPSs through Co-S coordination, and the conductive metallic Co can improve electronic conductivity and reduce impedance, which is beneficial for ion diffusion at the cathode. Based on these synergistic effects, the CoOx/CS electrode exhibits accelerated redox kinetics and enhanced catalytic activity for conversion of LiPSs. Consequently, the CoOx/CS cathode delivers improved cycling performance, with an initial capacity of 980.8 mA h g-1 at 0.1C and a reversible specific capacity of 408.4 mA h g-1 after 200 cycles, along with enhanced rate performance. This work provides a facile route to construct cobalt-based catalytic electrodes for Li-S batteries, and promotes understanding of the LiPSs conversion mechanism.
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BACKGROUND: Chemotherapy resistance is an important bottleneck affecting the efficacy of chemotherapy in colon cancer. Therefore, improving the chemotherapy sensitivity of colorectal cancer cells is of great significance for improving the prognosis of patients with colon cancer. METHODS: CCK-8 assay was employed to examine the cell viability of colorectal cancer cell lines. Realtime-PCR and western blot were used to explore toll-like receptor 4 (TLR4) expression in colorectal cancer cell lines. The functions of TLR4 in the stemness of the colorectal cancer cell lines were analyzed by infecting cells with lentivirus containing TLR4 siRNA. RESULTS: We found that aspirin could effectively enhance the chemosensitivity of CT26 and HCT116 colorectal cancer cell lines. Aspirin can also inhibit the stemness of colorectal cancer cell including inhibiting the number of clone formation and reducing the volume and number of cell spheres and inducing the down-regulation of stemness-related genes. Besides that, aspirin also lead to down-regulation of TLR4 expression in colorectal cancer cells. The TLR4 positive colorectal cancer cells demonstrated a higher chemotherapy resistance potential than TLR4 negative colorectal cancer cells. In addition, the stemness of TLR4 positive colorectal cancer cells is stronger than TLR4 negative colorectal cancer cells. CONCLUSION: The results of our study indicate that aspirin increases chemosensitivity of colorectal cancer cells and inhibits the expression of toll-like receptor 4.
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In this work, g-C3N4/ZIF-8 heterojunction photocatalysts were synthesised by the process by which the metal-organic framework ZIF-8 nanoparticles were grown onto the g-C3N4 layer in situ. Bismuth element was doped into the as-prepared g-C3N4/ZIF-8 material and a new type of Bi@g-C3N4/ZIF-8 composite photocatalysts was manufactured, in which the doping element acts in adjusting the bandgap in the photocatalysts. The prepared photocatalysts were characterised by XRD, FESEM, TEM, FTIR, XPS, UV-VIS DRS, photoluminescence and photo-electrochemical experiments. The results show that the ZIF-8 nanoparticles grown in situ were well-formed onto the g-C3N4 layer, and bismuth was evenly doped into the gaps of the g-C3N4/ZIF-8 framework. The degradation rate of methylene blue by CNZ-1.5(Bi)-12, which was a photocatalyst composed of 12% Bi-doped with g-C3N4/ZIF-8 material (the mass ratio of g-C3N4: ZIF-8 = 1:1.5), reached 86.6% under visible light irradiation within 60â min. The free radical scavenging experiment and electron spin resonance spectroscopy showed that âOH was the main active substance. Bismuth doping into the photocatalytic system promotes the excitation of electrons from the valence band to the conduction band and provides a good channel for the transmission of photogenerated carriers as well. It is achieved that intensive visible light absorption, the enhanced separation efficiency of photogenerated carriers, and excellent thermal stability and high recyclability in the novel composite photocatalyst, owing to the synergistic effect of the introduced bismuth with the heterostructure of g-C3N4/ZIF-8. Therefore, the synthesised Bi@g-C3N4/ZIF-8 heterojunction photocatalysts may be used as a good photocatalyst for purifying and degrading organic matter in sewage.
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Grafito , Iluminación , Bismuto/química , Grafito/química , Catálisis , LuzRESUMEN
Atom-by-atom control of a catalyst surface is a central yet challenging topic in heterogeneous catalysis, which enables precisely confined adsorption and oriented approach of reactant molecules. Here, exposed surfaces with either consecutive Pd trimers (Pd3) or isolated Pd atoms (Pd1) are architected for Pd2Ga intermetallic nanoparticles (NPs) using reactive metal-support interaction (RMSI). At elevated temperatures under hydrogen, in situ atomic-scale transmission electron microscopy directly visualizes the refacetting of Pd2Ga NPs from energetically favorable (013)/(020) facets to (011)/(002). Infrared spectroscopy and acetylene hydrogenation reaction complementarily confirm the evolution from consecutive Pd3 to Pd1 sites of Pd2Ga catalysts with the concurrent fingerprinting CO adsorption and featured reactivities. Through theoretical calculations and modeling, we reveal that the restructured Pd2Ga surface results from the preferential arrangement of additionally reduced Ga atoms on the surface. Our work provides previously unidentified mechanistic insight into temperature-promoted RMSI and possible solutions to control and rearrange the surface atoms of supported intermetallic catalyst.
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Searching for the efficient and sustainable inhibitors to defend metal corrosion in the marine environment has received a great deal attention in both academia and industry. In this work, a new strategy was developed to encapsulate benzimidazole (BI) inhibitor guest molecules into the micropores of bio-MOF-1, which was constructed with the other natural adenine inhibitor. Electrochemical characterizations revealed that the slowly sustained release of BI and adenine inhibitors from the BI@bio-MOF-1 composite presented excellent anti-corrosion durability in the whole mild steel corrosion process. The impedance arc value attained approximately 5000 Ω·cm2 at initially 2 h and further increased to 6000 Ω·cm2 after 5 days immersion in 0.5 M NaCl solution, and the inhibition efficiency reached 85.36% due to the synergistic dual inhibitive effect of BI@bio-MOF-1 composite. The dual inhibition-based bio-MOF-1 composite equipped strong metal-chelating capability and response durability, exhibiting high potentiality for metal anti-corrosion applications.
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Adenina , Acero , Corrosión , Acero/químicaRESUMEN
Catalysis is regarded as an effective strategy to fundamentally increase sulfur utilization, accelerating the kinetics of the transformation between lithium polysulfides (LiPSs) and lithium sulfide (Li2 S) on a substrate. However, the intermodulation of catalysts and sulfur species is elusive, which is limited to the comprehensive analysis of electrochemical performance in the dynamic reaction process. Herein, cobalt nanoparticles loaded on MXene nanosheets (Co/Ti2 C) are selected as sulfur hosts and the representative catalyst. By combining ex situ electrochemical results and interfacial structural chemical monitoring, the catalysis process of Co/Ti2 C toward LiPSs conversion is revealed, and the outstanding performance originates from the optimization of chemical adsorption, catalytic activity, and lithium-ion transfer behaviors, which is based on electronic/ion modulation and sufficient interfaces among catalysts and electrolyte. This work can guide the construction of electronic modulation at triple-phase interface catalysis to overcome the shuttle effect and facilitate sulfur redox kinetics in Li-S batteries.
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Osteoporosis (OP) is characterized by the flaccidity of bones or bone bi-disease caused by kidney deficiency. Lindera aggregate has been used to strengthen kidney function in China for thousands of years. It has been approved by Chinese Pharmacopoeia that the root of Lindera aggregata (RLA) can replenish and tonify the kidney, which is thought to be an effective way to alleviate OP. In this study, a network pharmacology approach was applied to explore the active components and potential mechanisms of RLA in osteoporosis treatment. Then, the ethanolic extract of the root of L. aggregata (EERL) was prepared and these predicted results were validated by prednisone-induced zebrafish embryos model. Moreover, the candidate compounds were identified by UPLC-ESI-MS/MS. The anti-OP results showed that EERL could significantly reverse the bone loss of zebrafish induced by prednisone. The mRNA expressions results showed that EERL decreased osteoclast bone resorption by regulating the RANK/RANKL/OPG system. Also, it increased bone formation by regulating the gene expressions of spp1, mmp2, mmp9, runx2b, alp, and entpd5a. Our results demonstrated the reliability of the network pharmacology method, and also revealed the anti-OP effect and potential mechanism of RLA.
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Lindera , Osteoporosis , Animales , Lindera/metabolismo , Farmacología en Red , Osteoporosis/inducido químicamente , Osteoporosis/tratamiento farmacológico , Osteoporosis/genética , Prednisona/efectos adversos , Ligando RANK/metabolismo , Reproducibilidad de los Resultados , Espectrometría de Masas en Tándem , Pez Cebra/metabolismoRESUMEN
Selective hydrogenation of substituted nitroaromatic compounds is an extremely important and challenging reaction. Supported metal catalysts attract much attention in this reaction because the properties of metal nanoparticles (NPs) can be modified by the nature of the support. Herein, the support morphology on the catalytic performance of selective hydrogenation of 3-nitrostyrene to 3-vinylaniline was investigated. Pt NPs supported on octadecahedral α-Fe2 O3 supports with a truncated hexagonal bipyramid shape (Pt/α-Fe2 O3 -O) and rod-shaped α-Fe2 O3 supports (Pt/α-Fe2 O3 -R) were prepared by glycol reduction method. Detailed characterizations reveal that the electronic structure and dispersion of Pt NPs can be modified by the supports. The Pt/α-Fe2 O3 -O catalyst exhibited superior catalytic performance for hydrogenation of 3-nitrostyrene because of its low coordinated Pt sites and the small Pt NPs size, which is benefit from the high-index exposed surfaces of truncated hexagonal bipyramid-shaped α-Fe2 O3 support. The structural evolution during the catalytic reaction was investigated in detail by identical location transmission electron microscopy (IL-TEM) method, which found that the high cycling activity of Pt/α-Fe2 O3 -O catalyst during the cycle experiment results from the stability of Pt NPs.
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Nanoreactors with a delimited void space and a large number of mesoporous structures have attracted great attention as potential heterogeneous catalysts. In this work, a cobalt and nitrogen co-doped binary carbon@silica@carbon hydrophobic nanoreactor was synthesized by an in situ synthesis method. Cobalt porphyrin was used as an active component to construct Co-Nx sites, and the purpose of the double carbon layer coating was to enhance the hydrophobicity of the surface of the nanoreactor. The optimal nanoreactor could achieve 96.9% ethylbenzene conversion and 99.1% acetophenone selectivity and showed outstanding universality to many other aromatic alkanes. The superior performance was mainly due to the presence of double carbon layers and the high content of Co-Nx sites. The double hydrophobic carbon layer coating could not only promote the adsorption of organic molecules, but also implant Co-Nx active sites on both the inner and outer surfaces of the nanoreactor. This work proposed a meaningful strategy to obtain a highly efficient nanoreactor for C-H bond oxidation.