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BACKGROUND: Hepatocellular carcinoma (HCC) is a malignant tumor with significant variability in prognosis among patients. Ras-related C3 botulinum toxin substrate 1 (RAC1) is a key focus in the area of cancer research. However, the molecular mechanisms of RAC1 in HCC remain incompletely elucidated. MATERIALS AND METHODS: In this study, bioinformatics analysis was used, and public databases were used to obtain information about HCC cases. The samples were categorized into two groups of high and low expression based on the expression level of RAC1 gene. The limma package was used to calculate the differentially expressed genes between the two groups, and univariate Cox regression analysis was used to screen the prognostic related factors. Consensus clustering analysis was performed using the ConsensusClusterPlus package to identify molecular subtypes of HCC patients. Immune cell infiltration and ESTIMATE scores were assessed using the single sample gene set enrichment analysis and ESTIMATE algorithms. The sensitivity of different isoforms to chemotherapeutic agents was predicted by the oncoPredict package. Finally, we also performed cell function experiments to validate the biological role of RAC1 in vitro. Initially, we classified patients into high and low expression groups based on RAC1 gene expression levels and identified 195 up-regulated genes and 107 down-regulated genes. Through univariate Cox regression analysis, we screened out 169 prognosis-related factors. Furthermore, HCC patients were categorized into two subtypes. Subsequently, Kaplan-Meier survival curves showed that there was a significant difference in prognosis between the two molecular subtypes. Further analysis indicated substantial differences in gene expression levels and TIDE scores between two molecular subtypes. Moreover, these two subtypes exhibited varying sensitivity to chemotherapy drugs, as evidenced by differences in IC50 values. In addition, we found that the silence of RAC1 could effectively inhibit the migration and invasion of HCC cells in vitro. CONCLUSION: This study sheds light on the molecular intricacies of RAC1 in HCC and identifies patient populations that may benefit from immunotherapeutic interventions, with potential implications for tailored treatment strategies.
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Biomarcadores de Tumor , Carcinoma Hepatocelular , Biología Computacional , Regulación Neoplásica de la Expresión Génica , Neoplasias Hepáticas , Proteína de Unión al GTP rac1 , Humanos , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/inmunología , Carcinoma Hepatocelular/mortalidad , Proteína de Unión al GTP rac1/genética , Proteína de Unión al GTP rac1/metabolismo , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/inmunología , Neoplasias Hepáticas/mortalidad , Pronóstico , Biología Computacional/métodos , Biomarcadores de Tumor/genética , Perfilación de la Expresión Génica , Línea Celular Tumoral , Estimación de Kaplan-MeierRESUMEN
Lead-free halide perovskites as a new kind of potential candidate for photocatalytic organic synthesis have attracted much attention recently. The rational heterojunction construction is regarded as an efficient strategy to delicately regulate their catalytic performances. Herein, a semi-conductive covalent organic framework (COF) nanosheet, C4N, is employed as the functional component to construct Cs2AgBiCl6/C4N (CABC/C4N) heterojunction. It is found that the C4N nanosheets with rich surface functional groups can serve as heterogeneous nucleation sites to manipulate the growth of CABC nanocrystals and afford close contact between each other, therefore facilitate the transfer and spatial separation of photogenerated charge carriers, as verified by in situ X-ray photoelectronic spectroscopy and Kelvin probe force microscopy. Moreover, the oxygen affinity of C4N endows the heterojunctions with outstanding aerobic reactivity, thus improving the photocatalytic performance largely. The optimal CABC/C4N heterojunction delivers a thioanisole conversion efficiency of 100% after 6 h, which is 2.2 and 7.7-fold of that of CABC and C4N. This work provides a new ideal for the design and application of lead-free perovskite heterojunction photocatalysts for organic reactions.
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Low-dimensional perovskites afford improved stability against moisture, heat, and ionic migration. However, the low dimensionality typically results in a wide bandgap and strong electron-phonon coupling, which is undesirable for optoelectronic applications. Herein, semiconducting A-site organic cation engineering by electron-acceptor bipyridine (bpy) cations (2,2'-bpy2+ and 4,4'-bpy2+) is employed to optimize band structure in low-dimensional perovskites. Benefiting from the merits of lower lowest unoccupied molecular orbital (LUMO) energy for 4,4'-bpy2+ cation, the corresponding (4,4'-bpy)PbI4 is endowed with a smaller bandgap (1.44 eV) than the (CH3NH3)PbI3 (1.57 eV) benchmark. Encouragingly, an intramolecular type II band alignment formation between inorganic Pb-I octahedron anions and bpy2+ cations favors photogenerated electron-hole pairs separation. In addition, a shortening distance between inorganic Pb-I octahedral chains in (4,4'-bpy)PbI4 single crystal (SC) can effectively promote carrier transfer. As a result, a self-powered photodetector based on (4,4'-bpy)PbI4 SC exhibits 131 folds higher on/off ratio (3807) than the counterpart of (2,2'-bpy)2Pb3I10 SC (29). The presented result provides an effective strategy for exporting novel organic cation-based low-dimensional perovskite SC for high-performance optoelectronic devices.
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BACKGROUND: The anticoagulation strategy of switching to rivaroxaban after 1 week of initial low-molecular-weight heparin (LMWH) therapy is recommended by a guideline for the treatment of acute iliofemoral deep vein thrombosis (DVT). However, the initial rivaroxaban dose in the switching strategy, as well as the effectiveness and safety of the early switching (less than 1 week) to rivaroxaban, remain inadequately substantiated. We aimed to evaluate the effectiveness and safety of early switching from LMWH to maintenance therapy of rivaroxaban (20 mg once daily) for acute iliofemoral DVT. METHODS: A retrospective cohort study was conducted using data from patients with acute iliofemoral DVT who received initial LMWH anticoagulation followed by rivaroxaban maintenance therapy. The clinical outcomes were compared between early (LMWH course ≤7 days) and routine (LMWH course >7 days) switching strategies within 3 months of initiating anticoagulation. RESULTS: 217 patients were included, 59 (27.2%) receiving early switching and 158 (72.8%) receiving routine switching. Compared with routine switching, patients with early switching had a significantly shorter hospital stay (7 days vs. 14 days, P < 0.001). The length of hospital stay was significantly positively correlated with the duration of LMWH (r = 0.762, P < 0.001). The incidences of recurrent venous thromboembolism (5.1% vs. 2.5%, P = 0.606), major bleeding (0% vs. 1.9%, P = 0.564), clinically relevant nonmajor bleeding (1.7% vs. 2.5%, P = 1.000) and all-cause mortality (6.8% vs. 2.5%, P = 0.283) were not statistically different between the 2 groups. CONCLUSIONS: Direct early switching from LMWH to maintenance therapy of rivaroxaban is effective and safe for acute iliofemoral DVT.
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Esquema de Medicación , Sustitución de Medicamentos , Inhibidores del Factor Xa , Vena Femoral , Hemorragia , Heparina de Bajo-Peso-Molecular , Vena Ilíaca , Rivaroxabán , Trombosis de la Vena , Humanos , Rivaroxabán/efectos adversos , Rivaroxabán/administración & dosificación , Estudios Retrospectivos , Trombosis de la Vena/tratamiento farmacológico , Trombosis de la Vena/diagnóstico por imagen , Trombosis de la Vena/mortalidad , Trombosis de la Vena/diagnóstico , Masculino , Femenino , Persona de Mediana Edad , Resultado del Tratamiento , Inhibidores del Factor Xa/efectos adversos , Inhibidores del Factor Xa/administración & dosificación , Factores de Tiempo , Anciano , Hemorragia/inducido químicamente , Vena Ilíaca/diagnóstico por imagen , Heparina de Bajo-Peso-Molecular/efectos adversos , Heparina de Bajo-Peso-Molecular/administración & dosificación , Factores de Riesgo , Adulto , Enfermedad Aguda , Tiempo de Internación , Recurrencia , Anticoagulantes/efectos adversos , Anticoagulantes/administración & dosificaciónRESUMEN
Chemodynamic therapy (CDT) is a newly developed cancer-therapeutic modality that kills cancer cells by the highly toxic hydroxyl radical (ËOH) generated from the in situ triggered Fenton/Fenton-like reactions in an acidic and H2O2-overproduced tumor microenvironment (TME). By taking the advantage of the TME-activated catalytic reaction, CDT enables a highly specific and minimally-invasive cancer treatment without external energy input, whose efficiency mainly depends on the reactant concentrations of both the catalytic ions and H2O2, and the reaction conditions (including pH, temperature, and amount of glutathione). Unfortunately, it suffers from unsatisfactory therapy efficiency for clinical application because of the limited activators (i.e., mild acid pH and insufficient H2O2 content) and overexpressed reducing substance in TME. Currently, various synergistic strategies have been elaborately developed to increase the CDT efficiency by regulating the TME, enhancing the catalytic efficiency of catalysts, or combining with other therapeutic modalities. To realize these strategies, the construction of diverse nanocarriers to deliver Fenton catalysts and cooperatively therapeutic agents to tumors is the key prerequisite, which is now being studied but has not been thoroughly summarized. In particular, nanocarriers that can not only serve as carriers but are also active themselves for therapy are recently attracting increasing attention because of their less risk of toxicity and metabolic burden compared to nanocarriers without therapeutic capabilities. These therapy-active nanocarriers well meet the requirements of an ideal therapy system with maximum multifunctionality but minimal components. From this new perspective, in this review, we comprehensively summarize the very recent research progress on nanocarrier-based systems for enhanced CDT and the strategies of how to integrate various Fenton agents into the nanocarriers, with particular focus on the studies of therapy-active nanocarriers for the construction of CDT catalysts, aiming to guide the design of nanosystems with less components and more functionalities for enhanced CDT. Finally, the challenges and prospects of such a burgeoning cancer-theranostic modality are outlooked to provide inspirations for the further development and clinical translation of CDT.
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Peróxido de Hidrógeno , Neoplasias , Humanos , Catálisis , Glutatión , Radical Hidroxilo , Temperatura , Neoplasias/tratamiento farmacológico , Línea Celular Tumoral , Microambiente TumoralRESUMEN
Low Earth orbit (LEO) satellite communication (SATCOM) networks have gradually been recognized as an efficient solution to enhance ground-based wireless networks. As one of the main characteristics of LEO SATCOM, the beam-edge area could be covered by multiple satellite nodes. In this case, user terminals (UTs) located at the beam-edge have the chance to connect one or more LEO satellites. To develop the diversity gain of multiple nodes in the overlapping area, we propose two high spectral efficiency cooperative transmission strategies, i.e., directly combining (DC) and selection combining (SC). In the DC scheme, signals arrived at the UT simultaneously could be combined into one enhanced signal. For downlink time division multiplexing, the SC scheme enables the UT to select the strongest signal path. Further, as there exists a significant channel gain difference of the beam-center and beam-edge areas, UTs in these two areas can be allocated in one resource block. In this case, we derive co-carriers based on DC and SC, respectively. To deeply analyze the novel methods, we study the ergodic sum-rate and outage probability while the outage diversity gain is further provided. Simulation results show that the co-carrier-based DC method has the ability to provide a higher ergodic sum-rate while the SC method performs better in terms of the outage probability.
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Organic scintillators are praised for their abundant element reserves, facile preparation procedures, and rich structures. Herein, a new family of highly efficient organic phosphonium halide salts with thermally activated delayed fluorescence (TADF) are designed by innovatively adopting quaternary phosphonium as the electron acceptor, while dimethylamine group and halide anions (I-) serve as the electron donor. The prepared butyl(2-[2-(dimethylamino)phenyl]phenyl)diphenylphosphonium iodide (C4-I) exhibits bright blue emission and an ultra-high photoluminescence quantum yield (PLQY) of 100%. Efficient charge transfer is realized through the unique n-π and anion-π stacking in solid-state C4-I. Photophysical studies of C4-I suggest that the incorporation of I accounts for high intersystem crossing rate (kISC) and reverse intersystem crossing rate (kRISC), suppressing the intrinsic prompt fluorescence and enabling near-pure TADF emission at room temperature. Benefitting from the large Stokes shift, high PLQY, efficient exciton utilization, and remarkable X-ray attenuation ability endowed by I, C4-I delivers an outstanding light yield of 80721 photons/MeV and a low limit of detection (LoD) of 22.79 nGy·s-1. This work would provide a rational design concept and open up an appealing road for developing efficient organic scintillators with tunable emission, strong X-ray attenuation ability, and excellent scintillator performance.
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Rational design and facile synthesis of efficient environmentally friendly all-inorganic lead-free halide perovskite catalysts are of great significance in photocatalytic CO2 reduction. Aiming at photogenerated charge carrier separation and CO2 reaction dynamics, in this paper, a CsCuCl3 /Cu nanocrystals (NCs) heterojunction catalyst is designed and synthesized via a simple acid-etching solution process by using Cu2 O as the sacrificed template. Due to the disproportionation reaction of Cu2 O induced by concentrated hydrochloric acid, Cu NCs can be deposited onto the surface of CsCuCl3 microcrystals directly and tightly. As revealed by photoelectrochemical analysis, in situ Fourier transform infrared spectra, etc., the Cu NCs contribute a lot to extracting photoelectrons of CsCuCl3 to improve the charge separation efficiency, regulating the CO2 adsorption and activation, and also stabilizing the reaction intermediates. Therefore, CsCuCl3 /Cu heterojunction exhibits a total electron consumption rate of 58.77 µmol g-1 h-1 , which is 2.9-fold of that of single CsCuCl3 . Moreover, high CH4 selectivity of up to 92.7% is achieved, which is much higher than that of CsCuCl3 (50.4%) and most lead-free halide perovskite-based catalysts. This work provides an ingenious but simple strategy to rationally design cocatalysts in situ decorated perovskite catalysts for manipulating both the catalytic activity and the product selectivity.
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This report describes a mild electrochemical α-oxygenation of a wide range of linear and cyclic benzamides mediated by N-hydroxyphthalimide (NHPI) in an undivided cell using O2 as the oxygen source and 2,4,6-trimethylpyridine perchlorate as an electrolyte. The radical scavenger experiment and the 18O labeling experiment were carried out, which indicated the involvement of a radical pathway and suggested O2 as an oxygen source in the imides, respectively.
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A variety of strategies for direct alkoxylation of the benzyl C-H bond have been developed toward the construction of benzyl ethers. The light-induced benzyl C-H bond alkoxylation provides an alternative strategy for the synthesis of these important intermediates. The photocatalyzed alkoxylation of the benzyl C-H bond has dominated by metal-catalyzed methods. Herein, we reported a light-driven organocatalytic approach for alkoxylation of the benzyl C-H bond by the use of 9,10-dibromoanthracene as a photocatalyst and employing N-fluorobenzenesulfonimide as an oxidant. This reaction proceeds at room temperature and is capable of converting a variety of alkyl biphenyl and coupling partners, including a variety of alcohol and carboxylic acid, as well as peroxide, to the desired products under 400 nm light irradiation.
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Ag-N-C catalyst was synthesized by the calcination process with AgNO3as precursors, active carbon as support, and melamine as an N source. Series of characterizations showed that Ag was transferred into AgCl during the active phase by HCl, and pyridinic structure in the support was bonded with Ag components. Then, Ag-N-C single atom catalyst (SAC) was obtained by washing Ag-N-C with acid, aberration-correction high-angle-annular-dark-field scanning transmission electron microscopy showed that Ag presented in single atoms form, and Ag coordinated with the nitrogen atom in the support. Ag loss rate for Ag-N-C SAC was only 0.09% after running 10 h in acetylene hydrochlorination process, which was much smaller than Ag-N-C (57%), indicating that the presence of the Ag-N bond could be inhibiting Ag species loss.
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Few therapeutic drugs and increased drug resistance have aggravated the current treatment difficulties of Cryptococcus in recent years. To better understand the antifungal drug resistance mechanism and treatment strategy of cryptococcosis. In this review, by combining the fundamental features of Cryptococcus reproduction leading to changes in its genome, we review recent research into the mechanism of four current anti-cryptococcal agents, coupled with new therapeutic strategies and the application of advanced technologies WGS and CRISPR-Cas9 in this field, hoping to provide a broad idea for the future clinical therapy of cryptococcosis.
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Criptococosis , Cryptococcus , Humanos , Cryptococcus/genética , Antifúngicos/farmacología , Antifúngicos/uso terapéutico , Criptococosis/tratamiento farmacológico , Criptococosis/microbiología , Farmacorresistencia Fúngica/genéticaRESUMEN
Data augmentation has been widely used to improve generalization in training deep neural networks. Recent works show that using worst-case transformations or adversarial augmentation strategies can significantly improve accuracy and robustness. However, due to the non-differentiable properties of image transformations, searching algorithms such as reinforcement learning or evolution strategy have to be applied, which are not computationally practical for large-scale problems. In this work, we show that by simply applying consistency training with random data augmentation, state-of-the-art results on domain adaptation (DA) and generalization (DG) can be obtained. To further improve the accuracy and robustness with adversarial examples, we propose a differentiable adversarial data augmentation method based on spatial transformer networks (STNs). The combined adversarial and random-transformation-based method outperforms the state-of-the-art on multiple DA and DG benchmark datasets. Furthermore, the proposed method shows desirable robustness to corruption, which is also validated on commonly used datasets.
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Algoritmos , Redes Neurales de la Computación , AclimataciónRESUMEN
Amyloid peptide (AP) self-assembly is a hierarchical process. However, the mechanistic rule of guiding peptides to organize well-ordered nanostructure in a clear and precise manner remains poorly understood. Herein we explored the molecular insight of AP motif aggregates underlying hierarchical process with helical fibrillar structure by atomic force microscope, cryo-electron microscopy (cryo-EM), and molecular dynamics simulation. AP assembly encompasses well-ordered twisted fibrils with uniform morphology, size, and periodicity. More importantly, a heterozipper ß-sheet was identified in a protofilament of AP assembly determined by cryo-EM with a high resolution of 3.5 Å. Each peptide heterozipper was further composed of two antiparallel ß strands and arranged by an alternative manner in a protofilament. The hydrophobic core and hydrophilic area in each zipper played the significant role for peptide assembling. This work proposed and verified the rule facilitating the basic building unit to form twisted fibrils and gave the explanation of peptide hierarchical assembling.
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Amiloide , Amiloidosis , Amiloide/química , Microscopía por Crioelectrón , Humanos , Simulación de Dinámica Molecular , Péptidos , Conformación Proteica en Lámina betaRESUMEN
The poor stability of carbon materials doped with nitrogen limited their development in acetylene hydrochlorination. Therefore, investigating the deactivation reasons of carbon catalysts and researching regeneration methods became the research focus. Herein, carbon-nitrogen materials were synthesized by one-step pyrolysis, which using biomass materials with high nitrogen content, the synthesized material was used in an acetylene hydrochlorination reaction. The acetylene conversion rate of D-GH-800 catalyst was up to 99%, but the catalytic activity decreased by 30% after 60 h reaction. Thermogravimetric analysis results showed that the coke content was 5.87%, resulting in catalyst deactivation. Temperature-programmed desorption verified that the deactivation was due to the strong adsorption and difficult desorption of acetylene by the D-GH-800 catalyst, resulting in the accumulation of acetylene on the catalyst surface to form carbon polymers and leading to the pore blockage phenomenon. Furthermore, based on the catalyst deactivation by carbon accumulation, we proposed a new idea of regeneration by ZnCl2 activation to eliminate carbon deposition in the pores of the deactivated catalyst. As a result, the activity of D-GH-800 was recovered, and lifetime was also extended. Our strategy illustrated the mechanism of carbon deposition, and the recoverability of the catalyst has promising applications.
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For the point-to-point additive white Gaussian noise (AWGN) channel with an eavesdropper and feedback, it has already been shown that the secrecy capacity can be achieved by a secret key-based feedback scheme, where the channel feedback is used for secret sharing, and then encrypting the transmitted message by the shared key. By secret sharing, any capacity-achieving coding scheme for the AWGN channel without feedback can be secure by itself, which indicates that the capacity of the same model without the secrecy constraint also affords an achievable secrecy rate to the AWGN channel with an eavesdropper and feedback. Then it is natural to ask: is the secret key-based feedback scheme still the optimal scheme for the AWGN multiple-access channel (MAC) with an external eavesdropper and channel feedback (AWGN-MAC-E-CF), namely, achieving the secrecy capacity region of the AWGN-MAC-E-CF? In this paper, we show that the answer to the aforementioned question is no, and propose the optimal feedback coding scheme for the AWGN-MAC-E-CF, which combines an existing linear feedback scheme for the AWGN MAC with feedback and the secret key scheme in the literature. This paper provides a way to find optimal coding schemes for AWGN multi-user channels in the presence of an external eavesdropper and channel feedback.
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BACKGROUND: The importance of optimising antimicrobial therapy is highlighted in the hospital intensive care unit (ICU) patients. But roles of ICU pharmacists are still in its infancy in China. OBJECTIVES: This study's objective was to evaluate the values of clinical pharmacist interventions in the antimicrobial stewardship (AMS) on ICU patients with infections. AIM: The aim of this study was to evaluate the value of clinical pharmacist interventions in the antimicrobial stewardship (AMS) in critically ill patients with infections. METHODS: From 2017 to 2019, a propensity score matching retrospective cohort research was conducted on critically ill patients with infectious illnesses. The trial was split into groups that received pharmacist assistance and those who did not. Baseline demographics, pharmacist actions, and clinical results were compared between the two groups. Factors influencing mortality were demonstrated using univariate analysis and bivariate logistic regression. The State Administration of Foreign Exchange in China monitored the exchange rate between the RMB and the US dollar and also gathered the charges of the agents as an economic indicator. RESULTS: Out of the 1523 patients who were evaluated, 102 critically ill patients with infectious diseases were included in each group after matching. The top five prescription regimens adjusted were settled by sickness progression, microbiological results, de-escalation, drug withdrawal, and therapeutic drug monitoring suggestions. The pharmacist exposure group's antibiotic use density (AUD) decreased significantly (p = 0.018) compared to the control group, going from 241.91 to 176.64 defined daily doses/100 bed days. Following pharmacist interventions, the AUD proportion for carbapenems dropped from 23.7 to 14.43%, while for tetracyclines, it dropped from 11.5 to 6.26%. In the group exposed to the pharmacist, the median cost of antibiotics decreased significantly from $836.3 to $362.15 per patient stay (p < 0.001), and the median cost of all medications dropped from $2868.18 to $1941.5 per patient stay (p = 0.06). RMB was converted into US dollars according to the current exchange rate. According to univariate analyses, pharmacist interventions did not differ between the groups that survived and died (p = 0.288). CONCLUSIONS: This study showed that antimicrobial stewardship had a significant financial return on investment without raising the mortality rate.
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Enfermedades Transmisibles , Farmacéuticos , Humanos , Estudios Retrospectivos , Enfermedad Crítica , Puntaje de Propensión , Enfermedades Transmisibles/tratamiento farmacológico , Cuidados Críticos/métodos , Antibacterianos/uso terapéuticoRESUMEN
Amyloid fibrils formed by peptides with different sequences exhibit diversified morphologies, material properties and activities, making them valuable for developing functional bionanomaterials. However, the molecular understanding underlying the structural diversity of peptide fibrillar assembly at atomic level is still lacking. In this study, by using cryogenic electron microscopy, we first revealed the structural basis underlying the highly reversible assembly of 1 GFGGNDNFG9 (referred to as hnRAC1) peptide fibril. Furthermore, by installing iodine at different sites of hnRAC1, we generated a collection of peptide fibrils with distinct thermostability. By determining the atomic structures of the iodinated fibrils, we discovered that iodination at different sites of the peptide facilitates the formation of diverse halogen bonds and triggers the assembly of entirely different structures of iodinated fibrils. Finally, based on this structural knowledge, we designed an iodinated peptide that assembles into new atomic structures of fibrils, exhibiting superior thermostability, that aligned with our design. Our work provides an in-depth understanding of the atomic-level processes underlying the formation of diverse peptide fibril structures, and paves the way for creating an amyloid "kaleidoscope" by employing various modifications and peptide sequences to fine-tune the atomic structure and properties of fibrillar nanostructures.
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Glass is a group of materials with appealing qualities, including simplicity in fabrication, durability, and high transparency, and they play a crucial role in the optics field. In this paper, a new organic-inorganic metal halide luminescent glass exhibiting >78 % transmittance at 506-800â nm range together with a high photoluminescence quantum yield (PLQY) of 28.5 % is reported through a low-temperature melt-quenching approach of pre-synthesized (HTPP)2 MnBr4 (HTPP=hexyltriphenylphosphonium) single crystal. Temperature-dependent X-ray diffraction, polarizing microscopy, and molecular dynamics simulations were combined to investigate the glass-crystal interconversion process, revealing the disordered nature of the glassy state. Benefiting from the transparent nature, (HTPP)2 MnBr4 glass yields an outstanding spatial resolution of 10â lp mm-1 for X-ray imaging. The superb optical properties and facility of large-scale fabrication distinguish the organic-inorganic metal halide glass as a highly promising class of materials for optical devices.
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Intraneuronal neurofibrillary tangles composed of Tau aggregates have been widely accepted as an important pathological hallmark of Alzheimer's disease. A current therapeutic avenue for treating Alzheimer's disease is aimed at inhibiting Tau accumulation with small molecules such as natural flavonoids. Liquid-liquid phase separation (LLPS) of Tau can lead to its aggregation, and Tau aggregates can then be degraded by autophagy. However, it is unclear whether natural flavonoids modulate the formation of phase-separated Tau droplets or promote autophagy and Tau clearance. Here, using confocal microscopy and fluorescence recovery after photobleaching assays, we report that a natural antioxidant flavonoid compound myricetin slows LLPS of full-length human Tau, shifting the equilibrium phase boundary to a higher protein concentration. This natural flavonoid also significantly inhibits pathological phosphorylation and abnormal aggregation of Tau in neuronal cells and blocks mitochondrial damage and apoptosis induced by Tau aggregation. Importantly, using coimmunoprecipitation and Western blotting, we show that treatment of cells with myricetin stabilizes the interaction between Tau and autophagy-related protein 5 (ATG5) to promote clearance of phosphorylated Tau to indirectly limit its aggregation. Consistently, this natural flavonoid inhibits mTOR pathway, activates ATG5-dependent Tau autophagy, and almost completely suppresses Tau toxicity in neuronal cells. Collectively, these results demonstrate how LLPS and abnormal aggregation of Tau are inhibited by natural flavonoids, bridging the gap between Tau LLPS and aggregation in neuronal cells, and also establish that myricetin could act as an ATG5-dependent autophagic activator to ameliorate the pathogenesis of Alzheimer's disease.