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Construction of mesoporous frameworks by noncovalent bonding still remains a great challenge. Here, we report a micelle-directed nanocluster modular self-assembly approach to synthesize a novel type of two-dimensional (2-D) hydrogen-bonded mesoporous frameworks (HMFs) for the first time based on nanoscale cluster units (1.0-3.0 nm in size). In this 2-D structure, a mesoporous cluster plate with â¼100 nm in thickness and several micrometers in size can be stably formed into uniform hexagonal arrays. Meanwhile, such a porous plate consists of several (3-4) dozens of layers of ultrathin mesoporous cluster nanosheets. The size of the mesopores can be precisely controlled from 11.6 to 18.5 nm by utilizing the amphiphilic diblock copolymer micelles with tunable block lengths. Additionally, the pore configuration of the HMFs can be changed from spherical to cylindrical by manipulating the concentration of the micelles. As a general approach, various new HMFs have been achieved successfully via a modular self-assembly of nanoclusters with switchable configurations (nanoring, Keggin-type, and cubane-like) and components (titanium-oxo, polyoxometalate, and organometallic clusters). As a demonstration, the titanium-oxo cluster-based HMFs show efficient photocatalytic activity for hydrogen evolution (3.6 mmol g-1h-1), with a conversion rate about 2 times higher than that of the unassembled titanium-oxo clusters (1.5 mmol g-1h-1). This demonstrates that HMFs exhibited enhanced photocatalytic activity compared with unassembled titanium-oxo clusters units.
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Sparse canonical correlation analysis (CCA) is a useful statistical tool to detect latent information with sparse structures. However, sparse CCA, where the sparsity could be considered as a Laplace prior on the canonical variates, works only for two data sets, that is, there are only two views or two distinct objects. To overcome this limitation, we propose a sparse generalized canonical correlation analysis (GCCA), which could detect the latent relations of multiview data with sparse structures. Specifically, we convert the GCCA into a linear system of equations and impose â1 minimization penalty to pursue sparsity. This results in a nonconvex problem on the Stiefel manifold. Based on consensus optimization, a distributed alternating iteration approach is developed, and consistency is investigated elaborately under mild conditions. Experiments on several synthetic and real-world data sets demonstrate the effectiveness of the proposed algorithm.
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Thanks to their excellent photoelectric characteristics to generate cytotoxic reactive oxygen species (ROS) under the light-activation process, TiO2 nanomaterials have shown significant potential in photodynamic therapy (PDT) for solid tumors. Nevertheless, the limited penetration depth of TiO2-based photosensitizers and excitation sources (UV/visible light) for PDT remains a formidable challenge when confronted with complex tumor microenvironments (TMEs). Here, we present a H2O2-driven black TiO2 mesoporous nanomotor with near-infrared (NIR) light absorption capability and autonomous navigation ability, which effectively enhances solid tumor penetration in NIR light-triggered PDT. The nanomotor was rationally designed and fabricated based on the Janus mesoporous nanostructure, which consists of a NIR light-responsive black TiO2 nanosphere and an enzyme-modified periodic mesoporous organosilica (PMO) nanorod that wraps around the TiO2 nanosphere. The overexpressed H2O2 can drive the nanomotor in the TME under catalysis of catalase in the PMO domain. By precisely controlling the ratio of TiO2 and PMO compartments in the Janus nanostructure, TiO2&PMO nanomotors can achieve optimal self-propulsive directionality and velocity, enhancing cellular uptake and facilitating deep tumor penetration. Additionally, by the decomposition of endogenous H2O2 within solid tumors, these nanomotors can continuously supply oxygen to enable highly efficient ROS production under the NIR photocatalysis of black TiO2, leading to intensified PDT effects and effective tumor inhibition.
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Raios Infravermelhos , Fotoquimioterapia , Fármacos Fotossensibilizantes , Titânio , Titânio/química , Titânio/farmacologia , Humanos , Porosidade , Animais , Camundongos , Fármacos Fotossensibilizantes/química , Fármacos Fotossensibilizantes/farmacologia , Nanoestruturas/química , Espécies Reativas de Oxigênio/metabolismo , Peróxido de Hidrogênio/química , Peróxido de Hidrogênio/metabolismo , Antineoplásicos/química , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Microambiente Tumoral/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Camundongos Endogâmicos BALB C , Proliferação de Células/efeitos dos fármacos , Neoplasias/tratamento farmacológico , Neoplasias/patologia , Tamanho da PartículaRESUMO
Self-assembly processes triggered by physical or chemical driving forces have been applied to fabricate hierarchical materials with subtle nanostructures. However, various physicochemical processes often interfere with each other, and their precise control has remained a great challenge. Here, in this paper, a rational synthesis of 1D magnetite-chain and mesoporous-silica-nanorod (Fe3O4&mSiO2) branched magnetic nanochains via a physical-chemical coupling coassembly approach is reported. Magnetic-field-induced assembly of magnetite Fe3O4 nanoparticles and isotropic/anisotropic assembly of mesoporous silica are coupled to obtain the delicate 1D branched magnetic mesoporous nanochains. The nanochains with a length of 2-3 µm in length are composed of aligned Fe3O4@mSiO2 nanospheres with a diameter of 150 nm and sticked-out 300 nm long mSiO2 branches. By properly coordinating the multiple assembly processes, the density and length of mSiO2 branches can well be adjusted. Because of the unique rough surface and length in correspondence to bacteria, the designed 1D Fe3O4&mSiO2 branched magnetic nanochains show strong bacterial adhesion and pressuring ability, performing bacterial inhibition over 60% at a low concentration (15 µg mL-1). This cooperative coassembly strategy deepens the understanding of the micro-nanoscale assembly process and lays a foundation for the preparation of the assembly with adjustable surface structures and the subsequent construction of complex multilevel structures.
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Omicron, as the emerging variant with enhanced vaccine tolerance, has sharply disrupted most therapeutic antibodies. Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) belongs to the subgenus Sarbecovirus, members of which share high sequence similarity. Herein, we report one sarbecovirus antibody, 5817, which has broad-spectrum neutralization capacity against SARS-CoV-2 variants of concern (VOCs) and SARS-CoV, as well as related bat and pangolin viruses. 5817 can hardly compete with six classes of receptor-binding-domain-targeted antibodies grouped by structural classifications. No obvious impairment in the potency is detected against SARS-CoV-2 Omicron and subvariants. The cryoelectron microscopy (cryo-EM) structure of neutralizing antibody 5817 in complex with Omicron spike reveals a highly conserved epitope, only existing at the receptor-binding domain (RBD) open state. Prophylactic and therapeutic administration of 5817 potently protects mice from SARS-CoV-2 Beta, Delta, Omicron, and SARS-CoV infection. This study reveals a highly conserved cryptic epitope targeted by a broad sarbecovirus neutralizing antibody, which would be beneficial to meet the potential threat of pre-emergent SARS-CoV-2 VOCs.
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Coronavírus Relacionado à Síndrome Respiratória Aguda Grave , Animais , Camundongos , Anticorpos Amplamente Neutralizantes , Microscopia Crioeletrônica , Anticorpos Neutralizantes , Epitopos , Anticorpos AntiviraisRESUMO
In the context of building Child-Friendly Cities in China, child-friendly school environments are considered as having a profound impact on children's development and growth. This study presents the development and validation of the Child-Friendly School Environment Questionnaire for assessing a child-friendly school environment. Utilizing open-ended questions and interviews, an initial questionnaire on the child-friendly school environment was compiled. An exploratory factor analysis of the preliminary test results with 696 primary school children in grades three to six was conducted to refine the questionnaire into a formal 19-item questionnaire. Subsequently, a confirmatory factor analysis was performed to analyze the evaluation results of 807 primary school children in grades three to six. The results indicated that a child-friendly school environment is a multi-dimensional construct encompassing Environment Friendly, Teaching Friendly, Peer Friendly, and Children Participation, with good reliability and validity. The promising outcomes of this study suggest that the Child-Friendly School Environment Questionnaire can be widely used as a powerful evaluation tool for the child-friendly school education practice in the future.
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A third dose of inactivated virus vaccine (IVV) boosts neutralizing antibodies, reducing SARS-CoV-2 transmission rate and COVID-19 severity. However, the impact of RBD-elicited antibodies and their neutralizing activity by the boost of IVV is unknown. We investigated the impact of IVV's boost shot on RBD-elicited antibodies and their neutralizing activity in 18 subjects receiving the second and third IVV doses. Using an RBD antibodies depletion assay, we assessed the neutralizing activity of RBD-elicited antibodies. After the second dose, RBD-antigen elicitation accounted for â¼60% of neutralizing activity, which increased to 82% after the IVV boost against ancestral SARS-CoV-2. Depleting class 3 and class 4-specific antibodies with the Beta-RBD protein revealed that NAbs targeting RBD class 1 and class 2 subdomains increased from 57% to 75% post-boost. These findings highlight the significant enhancement of RBD-specific antibodies, especially against RBD class 1 and class 2, with IVV booster doses. Our study offers valuable insights for optimizing COVID-19 vaccine strategies.
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COVID-19 , SARS-CoV-2 , Humanos , Epitopos , Vacinas de Produtos Inativados , Vacinas contra COVID-19 , COVID-19/prevenção & controle , Anticorpos , Anticorpos Bloqueadores , Anticorpos Neutralizantes , Anticorpos AntiviraisRESUMO
Bats are reservoir hosts for many zoonotic viruses. Despite this, relatively little is known about the diversity and abundance of viruses within individual bats, and hence the frequency of virus co-infection and spillover among them. We characterize the mammal-associated viruses in 149 individual bats sampled from Yunnan province, China, using an unbiased meta-transcriptomics approach. This reveals a high frequency of virus co-infection (simultaneous infection of bat individuals by multiple viral species) and spillover among the animals studied, which may in turn facilitate virus recombination and reassortment. Of note, we identify five viral species that are likely to be pathogenic to humans or livestock, based on phylogenetic relatedness to known pathogens or in vitro receptor binding assays. This includes a novel recombinant SARS-like coronavirus that is closely related to both SARS-CoV and SARS-CoV-2. In vitro assays indicate that this recombinant virus can utilize the human ACE2 receptor such that it is likely to be of increased emergence risk. Our study highlights the common occurrence of co-infection and spillover of bat viruses and their implications for virus emergence.
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COVID-19 , Quirópteros , Coinfecção , Coronavírus Relacionado à Síndrome Respiratória Aguda Grave , Animais , Humanos , Filogenia , SARS-CoV-2 , Viroma , China/epidemiologia , Coronavírus Relacionado à Síndrome Respiratória Aguda Grave/genéticaRESUMO
SARS-CoV Spike (S) protein shares considerable homology with SARS-CoV-2 S, especially in the conserved S2 subunit (S2). S protein mediates coronavirus receptor binding and membrane fusion, and the latter activity can greatly influence coronavirus infection. We observed that SARS-CoV S is less effective in inducing membrane fusion compared with SARS-CoV-2 S. We identify that S813T mutation is sufficient in S2 interfering with the cleavage of SARS-CoV-2 S by TMPRSS2, reducing spike fusogenicity and pseudoparticle entry. Conversely, the mutation of T813S in SARS-CoV S increased fusion ability and viral replication. Our data suggested that residue 813 in the S was critical for the proteolytic activation, and the change from threonine to serine at 813 position might be an evolutionary feature adopted by SARS-2-related viruses. This finding deepened the understanding of Spike fusogenicity and could provide a new perspective for exploring Sarbecovirus' evolution.
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COVID-19 , Coronavírus Relacionado à Síndrome Respiratória Aguda Grave , Humanos , Coronavírus Relacionado à Síndrome Respiratória Aguda Grave/genética , SARS-CoV-2/genética , SARS-CoV-2/metabolismo , Proteólise , Replicação Viral , Glicoproteína da Espícula de Coronavírus/metabolismo , Internalização do Vírus , Serina Endopeptidases/genética , Serina Endopeptidases/metabolismoRESUMO
The efficacy of phototherapy is dependent on intracellular O2 concentration and NIR harvest. Here, a simple nanoplatform with nanoenzyme mediated phototherapy enhances anticancer capacity. Mn-CoS@carbon (CMS/C) di-shell hollow nanospheres (50 nm) are synthesized successfully through two-step consecutive Kirkendall process. The nanoheterostructure reveals the higher near-infrared (NIR) light absorption and photothermal conversion rate of 66.3% than pure CoS (45.5%), owing to the decreased band gap and multi-reflection of incident light in the hollow structure. And CMS/C reveals the reactive oxygen species (ROS) production and nanoenzyme activities (mimic peroxidase and catalase) that are 6 and 2 times than those of pure CoS. Furthermore, the nanoenzyme exhibits NIR-enhanced abilities to produce more OH and O2 facilitating anticancer. In addition, it also depletes glutathione (mimicking glutathione oxidase), to disturb intracellular redox-homeostasis, boosting the increase of oxidative stress. With grafting bovine serum albumin (BSA) and drug loading, CMS/C@BSA-Dox integrated multi-therapy make the great anticancer effect in vitro and vivo. After that, the nanocomposite could be biodegraded and eliminated via urinary and feces within 14 days. Based on this work, the efficient charge-separation can be designed to reveal high performance nanoenzymes as well as photosensitizers for anticancer.
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Doxorrubicina , Nanosferas , Carbono , Doxorrubicina/química , Nanosferas/química , Fototerapia , Soroalbumina Bovina/químicaRESUMO
Dynamic changes of the paired heavy and light chain B cell receptor (BCR) repertoire provide an essential insight into understanding the humoral immune response post-SARS-CoV-2 infection and vaccination. However, differences between the endogenous paired BCR repertoire kinetics in SARS-CoV-2 infection and previously recovered/naïve subjects treated with the inactivated vaccine remain largely unknown. We performed single-cell V(D)J sequencing of B cells from six healthy donors with three shots of inactivated SARS-CoV-2 vaccine (BBIBP-CorV), five people who received the BBIBP-CorV vaccine after having recovered from COVID-19, five unvaccinated COVID-19 recovered patients and then integrated with public data of B cells from four SARS-CoV-2-infected subjects. We discovered that BCR variable (V) genes were more prominently used in the SARS-CoV-2 exposed groups (both in the group with active infection and in the group that had recovered) than in the vaccinated groups. The VH gene that expanded the most after SARS-CoV-2 infection was IGHV3-33, while IGHV3-23 in the vaccinated groups. SARS-CoV-2-infected group enhanced more BCR clonal expansion and somatic hypermutation than the vaccinated healthy group. A small proportion of public clonotypes were shared between the SARS-CoV-2 infected, vaccinated healthy, and recovered groups. Moreover, several public antibodies had been identified against SARS-CoV-2 spike protein. We comprehensively characterize the paired heavy and light chain BCR repertoire from SARS-CoV-2 infection to vaccination, providing further guidance for the development of the next-generation precision vaccine.
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COVID-19 , Vacinas Virais , Anticorpos Antivirais , COVID-19/prevenção & controle , Vacinas contra COVID-19 , Humanos , Receptores de Antígenos de Linfócitos B/genética , SARS-CoV-2/genética , Glicoproteína da Espícula de Coronavírus , VacinaçãoRESUMO
Objective: To analyze the epidemiological history, clinical symptoms, laboratory testing parameters of patients with mild and severe COVID-19 infection, and provide a reference for timely judgment of changes in the patients' conditions and the formulation of epidemic prevention and control strategies. Methods: A retrospective study was conducted in this research, a total of 90 patients with COVID-19 infection who received treatment from January 21 to March 31, 2020 in the Ninth People's Hospital of Dongguan City were selected as study subject. We analyzed the clinical characteristics of laboratory-confirmed patients with COVID-19, used the oversampling method (SMOTE) to solve the imbalance of categories, and established Lasso-logistic regression and random forest models. Results: Among the 90 confirmed COVID-19 cases, 79 were mild and 11 were severe. The average age of the patients was 36.1 years old, including 49 males and 41 females. The average age of severe patients is significantly older than that of mild patients (53.2 years old vs 33.7 years old). The average time from illness onset to hospital admission was 4.1 days and the average actual hospital stay was 18.7 days, both of these time actors were longer for severe patients than for mild patients. Forty-eight of the 90 patients (53.3%) had family cluster infections, which was similar among mild and severe patients. Comorbidities of underlying diseases were more common in severe patients, including hypertension, diabetes and other diseases. The most common symptom was cough [45 (50%)], followed by fever [43 (47.8%)], headache [7 (7.8%)], vomiting [3 (3.3%)], diarrhea [3 (3.3%)], and dyspnea [1 (1.1%)]. The laboratory findings of patients also included leukopenia [13(14.4%)] and lymphopenia (17.8%). Severe patients had a low level of creatine kinase (median 40.9) and a high level of D-dimer. The median NLR of severe patients was 2.82, which was higher than that of mild patients. Logistic regression showed that age, phosphocreatine kinase, procalcitonin, the lymphocyte count of the patient on admission, cough, fatigue, and pharynx dryness were independent predictors of COVID-19 severity. The classification of random forest was predicted and the importance of each variable was displayed. The variable importance of random forest indicates that age, D-dimer, NLR (neutrophil to lymphocyte ratio) and other top-ranked variables are risk factors. Conclusion: The clinical symptoms of COVID-19 patients are non-specific and complicated. Age and the time from onset to admission are important factors that determine the severity of the patient's condition. Patients with mild illness should be closely monitored to identify those who may become severe. Variables such as age and creatine phosphate kinase selected by logistic regression can be used as important indicators to assess the disease severity of COVID-19 patients. The importance of variables in the random forest further complements the variable feature information.
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COVID-19 , Linfopenia , Adulto , China/epidemiologia , Feminino , Hospitalização , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , SARS-CoV-2RESUMO
In this study, an environmental-friendly palladium catalyst with high efficiency, magnetic, recoverability, reusability, and excellent stability was prepared and thoroughly characterized by the Fourier transform infrared spectroscopy (FT-IR), Scanning electron microscopy (SEM), X-ray diffraction (XRD), Elemental mapping, Thermogravimetric analysis (TGA) and Energy-dispersive X-ray spectroscopy (EDX). Results demonstrates that melamine provides a coordination point on the surface of chitosan microspheres, which provides a platform for the uniform distribution of palladium (II) and combines with palladium (II) firmly to avoid unnecessary leaching of nanoparticles. Besides, Fe3O4/CS-Me@Pd microcapsules exhibited high catalytic performance in reducing p-NP in water at room temperature (150-300 s). This composite was also effective in the Suzuki-Miyaura coupling reaction under mild conditions with high catalytic performance (TON = 3.8 × 104, TOF = 7.6 × 104). Reproducibility experiments also showed that Fe3O4/CS-Me@Pd microcapsules have high recovery efficiency and can work at least six times during these two catalytic reactions. The hot filtration test indicated that the catalyst has heterogeneous nature.
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Quitosana/química , Nitrofenóis/química , Paládio/química , Triazinas/química , Água/química , Cápsulas , Catálise , Química Verde , Fenômenos Magnéticos , Microscopia Eletrônica de Varredura , Espectroscopia de Infravermelho com Transformada de Fourier , Difração de Raios XRESUMO
A linear route has been used to prepare (N)-methanocarba-nucleoside derivatives, which serve as purine receptor ligands having a pre-established, receptor-preferred conformation. To introduce this rigid ribose substitute, a Mitsunobu reaction of a [3.1.0]bicyclohexane 5'-trityl intermediate 3 with a nucleobase is typically followed by functional group modifications. We herein report an efficient scalable convergent synthesis for 2-substituted (N)-methanocarba-adenosines, which were demonstrated to bind to the A3 adenosine receptor. The adenine moiety was pre-functionalized with 2-thioethers and other groups before coupling to the bicyclic precursor (3) as a key step to facilitate a high yield Mitsunobu product. This new approach provided the (N)-methanocarba-adenosines in moderate to good yield, which effectively increased the overall yield compared to a linear synthesis and conserved a key intermediate 3 (a product of nine sequential steps). The generality of this convergent synthesis, which is suitable as an optimized preclinical synthetic route, was demonstrated with various 2-thioether and 2-methoxy substituents.
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Novel all-inorganic Sb-based lead-free double perovskite Cs2AgSbX6 (X = Cl, Br or I) quantum dots exhibiting excellent air stability and strong blue emission with photoluminescence quantum yields of 31.33% were synthesized for the first time using a surfactant-assisted method. The ligand, oleic acid, could control the crystallization of the pure perovskite phase and significantly passivate the surface.
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1ß-hydroxydeoxycholic acid in unlabeled and stable isotope labeled forms was required for use as a biomarker for Cytochrome P450 3A4/5 activity. A lengthy synthesis was undertaken to deliver the unlabeled compound and in the process, to develop a route to the deuterium labeled compound. The synthesis of the unlabeled compound was completed but in a very low yield. Concurrent with the synthetic approach, a biosynthetic route was pursued and this approach proved to be much more rapid and afforded the compound in both unlabeled and deuterium labeled forms in a 1-step oxidation from deoxycholic acid and [D4 ]deoxycholic acid, respectively.
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Ácido Quenodesoxicólico/análogos & derivados , Deutério/química , Técnicas de Química Sintética , Ácido Quenodesoxicólico/síntese química , Ácido Quenodesoxicólico/química , Citocromo P-450 CYP3A/metabolismo , Marcação por IsótopoRESUMO
A hydrothermal rota-crystallization method is developed for the one-step synthesis of a hollownest-structured zeolite precursor with the shell composed of autogenously-intergrown MWW nanosheet crystals containing a large number of stacking-pores without using any porogen or hard scaffold. This material possesses a large external surface area. By simple acid washing, the resultant Ti-containing catalyst can be directly used in the epoxidation of alkenes with hydrogen peroxide. The excellent catalytic activity over the Ti-HSZ catalyst is assumed to be due to the exposure of more Ti active sites over the MWW nanosheet crystals in the shell of the catalyst. More importantly, this Ti-HSZ catalyst washed with H2O2/ethanol solution has been reused 6 times without an appreciable decrease in both the conversion of the allyl chloride and the selectivity of the epichlorohydrin, which is ascribed to the structural stability of the hollownest-structured zeolite.