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Nickel is the most widely used inexpensive active metal center of the heterogeneous catalysts for CO2 hydrogenation to methane. However, Ni-based catalysts suffer from severe deactivation in CO2 methanation reaction due to the irreversible sintering and coke deposition caused by the inevitable localized hotspots generated during the vigorously exothermic reaction. Herein, we demonstrate the inverse CeAlOx/Ni composite constructed on the Ni-foam structure support realizes remarkable CO2 methanation catalytic activity and stability in a wide operation temperature range from 240 to 600 °C. Significantly, CeAlOx/Ni/Ni-foam catalyst maintains its initial activity after seven drastic heating-cooling cycles from RT to 240 to 600 °C. Meanwhile, the structure catalyst also shows water resistance and long-term stability under reaction condition. The promising thermal stability and water-resistance of CeAlOx/Ni/Ni-foam originate from the excellent heat and mass transport efficiency which eliminates local hotspots and the formation of Ni-foam stabilized CeAlOx/Ni inverse composites which effectively anchored the active species and prevents carbon deposition from CH4 decomposition.
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Introducing natural Bouligand structure into synthetics is expected to develop high-performance structural materials. Interfibrous interface is critical to load transfer, and mechanical functionality of bioinspired Bouligand structure yet receives little attention. Here, we propose one kind of hierarchical and reconfigurable interfibrous interface based on moderate orderliness to mechanically reinforce bioinspired Bouligand structure. The interface imparted by moderate alignment of adaptable networked nanofibers hierarchically includes nanofiber interlocking and hydrogen-bonding (HB) network bridging, being expected to facilitate load transfer and structural stability through dynamic adjustment in terms of nanofiber sliding and HB breaking-reforming. As one demonstration, the hierarchical and reconfigurable interfibrous interface is constructed based on moderate alignment of networked bacterial cellulose nanofibers. We show that the resultant bioinspired Bouligand structural material exhibits unusual strengthening and toughening mechanisms dominated by interface-microstructure multiscale coupling. The proposed interfibrous interface enabled by moderate orderliness would provide mechanical insight into the assembly of widely existing networked nanofiber building blocks toward high-performance macroscopic bioinspired structural assemblies.
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BACKGROUND: B56ε is a regulatory subunit of the serine/threonine protein phosphatase 2A, which is abnormally expressed in tumors and regulates various tumor cell functions. At present, the application of B56ε in pan-cancer lacks a comprehensive analysis, and its role and mechanism in hepatocellular carcinoma (HCC) are still unclear. AIM: To analyze B56ε in pan-cancer, and explore its role and mechanism in HCC. METHODS: The Cancer Genome Atlas, Genotype-Tissue Expression, Gene Expression Profiling Interactive Analysis, and Tumor Immune Estimation Resource databases were used to analyze B56ε expression, prognostic mutations, somatic copy number alterations, and tumor immune characteristics in 33 tumors. The relationships between B56ε expression levels and drug sensitivity, immunotherapy, immune checkpoints, and human leukocyte antigen (HLA)-related genes were further analyzed. Gene Set Enrichment Analysis (GSEA) was performed to reveal the role of B56ε in HCC. The Cell Counting Kit-8, plate cloning, wound healing, and transwell assays were conducted to assess the effects of B56ε interference on the malignant behavior of HCC cells. RESULTS: In most tumors, B56ε expression was upregulated, and high B56ε expression was a risk factor for adrenocortical cancer, HCC, pancreatic adenocarcinoma, and pheochromocytoma and paraganglioma (all P < 0.05). B56ε expression levels were correlated with a variety of immune cells, such as T helper 17 cells, B cells, and macrophages. There was a positive correlation between B56ε expression levels with immune checkpoint genes and HLA-related genes (all P < 0.05). The expression of B56ε was negatively correlated with the sensitivity of most chemotherapy drugs, but a small number showed a positive correlation (all P < 0.05). GSEA analysis showed that B56ε expression was related to the cancer pathway, p53 downstream pathway, and interleukin-mediated signaling in HCC. Knockdown of B56ε expression in HCC cells inhibited the proliferation, migration, and invasion capacity of tumor cells. CONCLUSION: B56ε is associated with the microenvironment, immune evasion, and immune cell infiltration of multiple tumors. B56ε plays an important role in HCC progression, supporting it as a prognostic marker and potential therapeutic target for HCC.
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Natural products and their analogues are significant sources of therapeutic lead compounds. However, synthetic strategies for generating large collections of these molecules remain a significant challenge. The most difficult step in their synthesis is the design of a common intermediate that can be easily transformed into natural products belonging to different families. This study demonstrates the evolution of synthetic tactics designed to assemble the functionalized piperidines present in indole alkaloids from a common intermediate. More importantly, we also report a previously unknown Ir- and Er-catalyzed dehydrogenative spirocyclization reaction that enables direct access to spirocyclic oxindole alkaloids. As a practical application, the asymmetric total syntheses of 29 natural alkaloids belonging to different families were accomplished by following a uniform synthetic route. The proposed methodology extends the capability of the iridium-catalyzed dehydrogenative coupling reaction to the realm of indole-alkaloid synthesis and provides new opportunities for the efficient preparation of natural product-like molecules.
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Alcaloides , Produtos Biológicos , Humanos , Estereoisomerismo , Alcaloides Indólicos , OxindóisRESUMO
OBJECTIVE: This study aimed to explore the clinical efficacy of metagenomic next-generation sequencing (mNGS) in diagnosing and treating suspected spinal infectious diseases. METHODS: Between October 2022 to December 2023, a retrospective analysis was performed on patient records within the Department of Spinal Surgery at Guilin People's Hospital. The analysis included comprehensive data on patients with presumed spinal infectious diseases, incorporating results from mNGS tests conducted externally, conventional pathogen detection results, laboratory examination results, and imaging findings. The study aimed to assess the applicability of mNGS in the context of suspected spinal infectious lesions. RESULTS: Twenty-seven patients were included in the final analysis. Pathogenic microorganisms were identified in 23 cases. The included cases encompassed 1 case of tuberculous spondylitis, 1 case of fungal infection, 3 cases of Brucella spondylitis, 3 cases of viral infection, 9 cases of bacterial infection, and 6 cases of mixed infections. Pathogenic microorganisms remained elusive in 4 cases. The application of the mNGS method demonstrated a significantly elevated positive detection rate compared to conventional methods (85.19% vs. 48.15%, P < 0.05). Moreover, the mNGS method detected a greater variety of pathogen species than traditional methods (Z = 10.69, P < 0.05). Additionally, the mNGS method exhibited a shorter detection time. CONCLUSIONS: mNGS demonstrated significantly higher detection rates for bacterial, fungal, viral, and mixed infections in cases of suspected spinal infectious diseases. The clinical implementation of mNGS could further enhance the efficiency of diagnosing and treating suspected spinal infectious diseases.
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[4 + 2] cycloaddition has led to diverse polycyclic chiral architectures, serving as novel sources for organic synthesis and biological exploration. Here, an unprecedented class of cadinane sesquiterpene [4 + 2] dimers, henryinins A-E (1-5), with a unique 6/6/6/6/6-fused pentacyclic system, were isolated from Schisandra henryi. The divergent total syntheses of compounds 1-5 and their enantiomers (6-10) were concisely accomplished in eight linear steps using a protection-free approach. Mechanistic studies illustrated the origin of selectivity in the key [4 + 2] cycloaddition as well as the inhibition of reaction pathway bifurcation via desymmetrization. The chemical proteomics results showed that a pair of enantiomers shared common targets (PRDX5 C100 and BLMH C73) and had unique targets (USP45 C588 for 4 and COG7 C419 for 9). This work provides experimental evidence for the discovery of unprecedented cadinane dimers from selective Diels-Alder reaction and a powerful strategy to explore the biological properties of natural products.
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Exploitation of key protected wild plant resources makes great sense, but their limited populations become the major barrier. A particular strategy for breaking this barrier was inspired by the exploration of a resource-saving fungal endophyte Penicillium sp. DG23, which inhabits the key protected wild plant Schisandra macrocarpa. Chemical studies on the cultures of this strain afforded eight novel indole diterpenoids, schipenindolenes A-H (1-8), belonging to six diverse skeleton types. Importantly, semisyntheses suggested some key nonenzymatic reactions constructing these molecules and provided targeted compounds, in particular schipenindolene A (Spidâ A, 1) with low natural abundance. Remarkably, Spidâ A was the most potent HMG-CoA reductase (HMGCR) degrader among the indole diterpenoid family. It degraded statin-induced accumulation of HMGCR protein, decreased cholesterol levels and acted synergistically with statin to further lower cholesterol. Mechanistically, transcriptomic and proteomic profiling suggested that Spidâ A potentially activated the endoplasmic reticulum-associated degradation (ERAD) pathway to enhance the degradation of HMGCR, while simultaneously inhibiting the statin-activated expression of many key enzymes in the cholesterol and fatty acid synthesis pathways, thereby strengthening the efficacy of statins and potentially reducing the side effects of statins. Collectively, this study suggests the potential of Spidâ A for treating cardiovascular disease.
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Acil Coenzima A , Inibidores de Hidroximetilglutaril-CoA Redutases , Inibidores de Hidroximetilglutaril-CoA Redutases/farmacologia , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Degradação Associada com o Retículo Endoplasmático , Proteômica , Colesterol/metabolismo , IndóisRESUMO
PURPOSE: The purpose of this study was to explore which therapeutic strategy is more beneficial for elderly esophageal cancer (EC) patients with distant metastasis, the treatment utilization status and the screening of factors related to prognosis, so as to better guide the treatment of these patients. METHODS: Patients in the Surveillance Epidemiology and End Results (SEER) database were divided into chemoradiotherapy (Group A), chemotherapy (Group B), radiotherapy (Group C), and no treatment (Group D) according to different treatment methods. Propensity score matching (PSM) was performed to adjust for baseline differences between the two groups. Overall survival (OS) and esophageal cancer-specific survival (ECSS) was calculated using the Kaplan-Meier method and compared using the log-rank test. RESULTS: A total of 7027 patients were included in this study, 5739 males (81.7%) and 1288 females (18.3%) with the median age was 70 (60-98). In the original cohort, the number of patients in the four groups was 2260 (Group A), 2087 (Group B), 945 (Group C) and 1735 (Group D), respectively. After PSM, there was no significant difference in mean OS (A vs B, 13.5 months VS 13.4 months, P = 0.511) and mean ECSS (A vs B, 15.6 vs 15.5 months, P = 0.374), while both OS (B vs C, 7 vs 3 months, P < 0.001) and ECSS (B vs C, 8 vs 3 months, P < 0.001) of chemotherapy alone were significantly better than those of radiotherapy alone. Subgroup analysis of patients older than 80 years showed that the median OS (A vs B, 7 vs 6 months) and median ECSS (A vs B, 8 vs 7 months) of Group A were significantly better than those of Group B (P < 0.05). In addition, all patients were randomly divided into a training set and a validation set with a ratio of 7:3. Based on the independent risk factors for OS, a nomogram model was constructed and validated. CONCLUSION: For elderly EC patients with distant metastasis, aggressive treatment was still necessary after a comprehensive assessment of the patient's physical condition, especially for patients over 80 years old, and chemoradiotherapy maybe still the first choice. In addition, a nomogram model was constructed to intuitively and accurately evaluate the prognosis of this population.
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Neoplasias Esofágicas , Idoso , Feminino , Masculino , Humanos , Idoso de 80 Anos ou mais , Prognóstico , Neoplasias Esofágicas/terapia , Nomogramas , Pacientes , QuimiorradioterapiaRESUMO
Spirophyllines A-D (1-4), four new spirooxindole alkaloids all characterized by the spiro[pyrrolidin-3,3'-oxindole] core and a rare isoxazolidine ring, were isolated from Uncaria rhynchophylla. Their structures were determined by spectroscopic methods and confirmed by X-ray crystallography. Based on the biomimetic semisynthesis strategy, compounds 1-8 were synthesized in three steps via the key reactions of 1,3-dipolar cycloaddition and Krapcho decarboxylation from corynoxeine. Interestingly, compound 3 showed moderate inhibitory activity against the Kv1.5 potassium channel (IC50 = 9.1 µM).
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Alcaloides , Uncaria , Alcaloides/química , Biomimética , Análise Espectral , Uncaria/químicaRESUMO
HLA-C*06:02:105 differs from HLA-C*06:02:01:01 by one nucleotide in exon 1.
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População do Leste Asiático , Antígenos HLA-C , Humanos , Alelos , Sequência de Bases , População do Leste Asiático/genética , Antígenos HLA-C/genética , Nucleotídeos , Análise de Sequência de DNARESUMO
(+)-Isoscopariusins B (1) and C (2), two meroditerpenoids containing a 6/6/4 tricyclic carbon skeleton and seven continuous stereocenters, were identified from Isodon scoparius. The structures were determined by nuclear magnetic resonance analysis and concise biomimetic syntheses from readily available alkene 5 in seven and six steps, respectively. An intermolecular [2+2] photocycloaddition with cooperative catalysis of a Lewis acid and an Ir photocatalyst was used to construct a cyclobutane core with four stereogenic centers.
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Ciclobutanos , Isodon , Estrutura Molecular , Biomimética , Espectroscopia de Ressonância Magnética , Isodon/química , Catálise , EstereoisomerismoRESUMO
Twenty new ent-kaurane diterpenoids, wardiisins A-T (1-20), along with two previously undescribed artefactual compounds (21 and 22) and twelve known analogues (23-34), were isolated from the aerial part of Isodon wardii. Their structures were elucidated by comprehensive analysis of spectroscopic data and single-crystal X-ray diffraction, and most of them were found to bear unusual C-12 oxygenation. Compounds 4, 7, 8, 19, 20, 21 exhibited remarkable cytotoxicity against the cancer cell lines HL-60, SMMC-7721, A-549, MDA-MB-231, and SW480, with IC50 values ranging from 0.3 to 5.2 µM. Moreover, 7 was found to induce G2/M cell cycle arrest and promote apoptosis in SW480 cell lines.
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Antineoplásicos Fitogênicos , Antineoplásicos , Diterpenos do Tipo Caurano , Diterpenos , Isodon , Humanos , Diterpenos do Tipo Caurano/farmacologia , Diterpenos do Tipo Caurano/química , Isodon/química , Antineoplásicos Fitogênicos/farmacologia , Antineoplásicos Fitogênicos/química , Ensaios de Seleção de Medicamentos Antitumorais , Componentes Aéreos da Planta/química , Antineoplásicos/farmacologia , Antineoplásicos/análise , Estrutura MolecularRESUMO
Five new cyclopiazonic acid related indole alkaloids, pegriseofamines A-E (1-5), were isolated from the fungus Penicillium griseofulvum. Their structures and absolute configurations were determined by NMR, HRESIMS, quantum-chemical calculation, and X-ray diffraction experiments. Among them, pegriseofamine A (1) possesses an undescribed 6/5/6/7 tetracyclic ring system generated by the fusion of an azepine and an indole unit via a cyclohexane, and the postulated biosynthetic origin of 1 was discussed. Compound 4 could relieve liver injury and prevent hepatocyte apoptosis in ConA-induced autoimmune liver disease.
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Alcaloides Indólicos , Penicillium , Alcaloides Indólicos/química , Penicillium/química , Fungos , Estrutura MolecularRESUMO
Investigation of the alkaloids from Myrioneuron effusum leads to the isolation of myrionsumamide A (1), a pair of enantiomeric alkaloids with an unprecedented tetracyclic system skeleton. These two alkaloids were separated by chiral HPLC with a ratio of 3 : 5 from the scalemic mixture. Their structures including absolute configurations were determined by NMR spectroscopy, X-ray diffraction data and ECD calculations. Both (+)-1 and (-)-1 showed antibacterial activity against Staphylococcus aureus with MIC at 7.81 µg ml-1.
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Auxin is a general coordinator for growth and development throughout plant lifespan, acting in a concentration-dependent manner. Tryptophan aminotransferases (YUCCA) family catalyze the oxidative decarboxylation of indole-3-pyruvic acid (IPA) to form indole-3-acetic acid (IAA) and plays a critical role in auxin homeostasis. Here, 18 YUCCA family genes divided into four categories were identified from Mikania micrantha (M. micrantha), one of the world's most invasive plants. Five highly conserved motifs were characterized in these YUCCA genes (MmYUCs). Transcriptome analysis revealed that MmYUCs exhibited distinct expression patterns in different organs and five MmYUCs showed high expression levels throughout all the five tissues, implying that they may play dominant roles in auxin biosynthesis and plant development. In addition, MmYUC6_1 was overexpressed in DR5::GUS Arabidopsis line to explore its function, which resulted in remarkably increased auxin level and typical elevated auxin-related phenotypes including shortened roots and elongated hypocotyls in the transgenic plants, suggesting that MmYUC6_1 promoted IAA biosynthesis in Arabidopsis. Collectively, these findings provided comprehensive insight into the phylogenetic relationships, chromosomal distributions, expression patterns and functions of the MmYUC genes in M. micrantha, which would facilitate the study of molecular mechanisms underlying the fast growth of M. micrantha and preventing its invasion.
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Proteínas de Arabidopsis , Arabidopsis , Mikania , Yucca , Arabidopsis/genética , Arabidopsis/metabolismo , Mikania/genética , Mikania/metabolismo , Yucca/genética , Yucca/metabolismo , Filogenia , Ácidos Indolacéticos/metabolismo , Proteínas de Arabidopsis/genética , Plantas Geneticamente Modificadas/metabolismo , Regulação da Expressão Gênica de PlantasRESUMO
Chemical studies on the culture broth of the endophytic fungus Alternaria sp. J030 led to the identification of three benzylated hydroxyacetophenone derivatives, bauvaroalterins A-C (1-3), and 34 structurally diverse metabolites (4-37). The new structures were elucidated by extensive spectroscopic analyses including UV, IR, 1D and 2D NMR, HR-ESI-MS, and further confirmed using single crystal X-ray diffraction. The inâ vitro anti-neuroinflammatory effects of the co-isolated metabolites were evaluated in lipopolysaccharide (LPS)-stimulated microglial cells. Compounds 1-3 were shown to significantly reduce LPS-induced NO production by inhibiting the expression of iNOS, as well as inhibiting LPS-induced production of the inflammatory factors TNF-α, IL-1ß and IL-6. Further studies revealed that 1-3 were capable of down-regulating the expression of NF-κB subunits p50 and p65, thereby suppressing the activation of NF-κB by inhibiting the LPS-induced phosphorylation of IκB-α. Together these findings demonstrate that bauvaroalterins A-C (1-3) exert anti-neuroinflammatory effects via inhibition of the NF-κB/iNOS signalling pathway in LPS induced BV-2 cells.
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Lipopolissacarídeos , NF-kappa B , Lipopolissacarídeos/farmacologia , Inibidor de NF-kappaB alfa/metabolismo , NF-kappa B/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Alternaria/metabolismo , Anti-Inflamatórios , Interleucina-6/metabolismo , MicrogliaRESUMO
Four emestrin hybrid polymers, asperemestrins A-D (1-4, respectively), were isolated from the fungus Aspergillus nidulans. Asperemestrins A-C are the first examples of emestrin-sterigmatocystin heterodimers bearing a 7/5/6/6/5/5/6/6/6 nonacyclic system with a 2,5-diazabicyclo[2.2.2]octane-3,6-dione core, while asperemestrin D features an unprecedented 2,15-dithia-17,19-diazabicyclo[14.2.2]icosa-4,8-diene-12,18,20-trione core skeleton. Their structures were determined by extensive spectroscopic data, electronic circular dichroism calculations, and single-crystal X-ray diffraction. Asperemestrin B showed moderate cytotoxicity against cancer cell lines, including SU-DHL-2, HEPG2, and HL-60.
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Aspergillus nidulans , Aspergillus nidulans/metabolismo , Dicroísmo Circular , Humanos , Estrutura Molecular , Octanos , Piperazinas , Polímeros , Esterigmatocistina/metabolismoRESUMO
With the advance of invasive interventions, the treatment model for infected necrotizing pancreatitis (INP) has shifted from open surgery to the step-up minimally invasive treatment. Late intervention, originating from the open surgery era, has been questioned in the minimally invasive period. With the emergence of new high-quality evidence about the timing for intervention, it seems to be increasingly apparent that, even in the age of minimal invasiveness, "late intervention" waiting for the necrotic collections to be encapsulated is still necessary. This opinion review mainly discusses the intervention timing for INP.