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Significant advances have been made in materials for biomedical applications, including tissue engineering, bioimaging, cancer treatment, etc. In the past few decades, nanostructure-mediated therapeutic strategies have been developed to improve drug delivery, targeted therapy, and diagnosis, maximizing therapeutic effectiveness while reducing systemic toxicity and side effects by exploiting the complicated interactions between the materials and the cell and tissue microenvironments. This review briefly introduces the differences between the cells and tissues of tumour or normal cells. We summarize recent advances in tumour microenvironment-mediated therapeutic strategies using nanostructured materials. We then comprehensively discuss strategies for fabricating nanostructures with cancer cell-specific cytotoxicity by precisely controlling their composition, particle size, shape, structure, surface functionalization, and external energy stimulation. Finally, we present perspectives on the challenges and future opportunities of nanotechnology-based toxicity strategies in tumour therapy.
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Precision therapy has become the preferred choice attributed to the optimal drug concentration in target sites, increased therapeutic efficacy, and reduced adverse effects. Over the past few years, sprayable or injectable thermosensitive hydrogels have exhibited high therapeutic potential. These can be applied as cell-growing scaffolds or drug-releasing reservoirs by simply mixing in a free-flowing sol phase at room temperature. Inspired by their unique properties, thermosensitive hydrogels have been widely applied as drug delivery and treatment platforms for precision medicine. In this review, the state-of-the-art developments in thermosensitive hydrogels for precision therapy are investigated, which covers from the thermo-gelling mechanisms and main components to biomedical applications, including wound healing, anti-tumor activity, osteogenesis, and periodontal, sinonasal and ophthalmic diseases. The most promising applications and trends of thermosensitive hydrogels for precision therapy are also discussed in light of their unique features.
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Few-shot image classification involves recognizing new classes with a limited number of labeled samples. Current local descriptor-based methods, while leveraging consistent low-level features across visible and invisible classes, face challenges including redundant adjacent information, irrelevant partial representation, and limited interpretability. This paper proposes KLSANet, a few-shot image classification approach based on key local semantic alignment network, which aligns key local semantics for accurate classification. Furthermore, we introduce a key local screening module to mitigate the influence of semantically irrelevant image parts on classification. KLSANet demonstrates superior performance on three benchmark datasets (CUB, Stanford Dogs, Stanford Cars), outperforming state-of-the-art methods in 1-shot and 5-shot settings with average improvements of 3.95% and 2.56% respectively. Visualization experiments demonstrate the interpretability of KLSANet predictions. Code is available at: https://github.com/ZitZhengWang/KLSANet.
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Redes Neurais de Computação , Semântica , Animais , Processamento de Imagem Assistida por Computador/métodos , Algoritmos , Cães , Reconhecimento Automatizado de Padrão/métodosRESUMO
The African swine fever virus (ASFV) has the ability to infect pigs and cause a highly contagious acute fever that can result in a mortality rate as high as 100%. Due to the viral epidemic, the pig industry worldwide has suffered significant financial setbacks. The absence of a proven vaccine for ASFV necessitates the development of a sensitive and reliable serological diagnostic method, enabling laboratories to effectively and expeditiously detect ASFV infection. In this study, four strains of monoclonal antibodies (mAbs) against p72, namely, 5A1, 4C4, 8A9, and 5E10, were generated through recombinant expression of p72, the main capsid protein of ASFV, and immunized mice with it. Epitope localization was performed by truncated overlapping polypeptides. The results indicate that 5A1 and 4C4 recognized the amino acid 20-39 aa, 8A9 and 5E10 are recognized at 263-282 aa, which is consistent with the reported 265-280 aa epitopes. Conserved analysis revealed 20-39 aa is a high conservation of the epitopes in the ASFV genotypes. Moreover, a blocking ELISA assay for detection ASFV antibody based on 4C4 monoclonal antibody was developed and assessed. The receiver-operating characteristic (ROC) was performed to identify the best threshold value using 87 negative and 67 positive samples. The established test exhibited an area under the curve (AUC) of 0.9997, with a 95% confidence interval ranging from 99.87 to 100%. Furthermore, the test achieved a diagnostic sensitivity of 100% (with a 95% confidence interval of 95.72 to 100%) and a specificity of 98.51% (with a 95% confidence interval of 92.02 to 99.92%) when the threshold was set at 41.97%. The inter- and intra-batch coefficient of variation were below 10%, demonstrating the exceptional repeatability of the method. This method can detect the positive standard serum at a dilution as high as 1:512. Subsequently, an exceptional blocking ELISA assay was established with high diagnostic sensitivity and specificity, providing a novel tool for detecting ASFV antibodies. KEY POINTS: ⢠Four strains of ASFV monoclonal antibodies against p72 were prepared and their epitopes were identified. ⢠Blocking ELISA method was established based on monoclonal antibody 4C4 with an identified conservative epitope. ⢠The established blocking ELISA method has a good effect on the detection of ASFV antibody.
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Vírus da Febre Suína Africana , Febre Suína Africana , Anticorpos Monoclonais , Anticorpos Antivirais , Proteínas do Capsídeo , Ensaio de Imunoadsorção Enzimática , Mapeamento de Epitopos , Animais , Anticorpos Monoclonais/imunologia , Vírus da Febre Suína Africana/imunologia , Vírus da Febre Suína Africana/genética , Ensaio de Imunoadsorção Enzimática/métodos , Anticorpos Antivirais/sangue , Anticorpos Antivirais/imunologia , Suínos , Febre Suína Africana/diagnóstico , Febre Suína Africana/imunologia , Febre Suína Africana/virologia , Camundongos , Proteínas do Capsídeo/imunologia , Proteínas do Capsídeo/genética , Camundongos Endogâmicos BALB C , Sensibilidade e Especificidade , Epitopos/imunologiaRESUMO
Few-shot classification recognizes novel categories with limited labeled samples. The classic Relation Network (RN) compares support-query sample pairs for few-shot classification but overlooks support set contextual information, limiting its comparison capabilities. This work reformulates learning the relationship between query samples and each support class as a seq2seq problem. We introduce a Sample-level Transformer-based Relation Network (SLTRN) that utilizes sample-level self-attention to enhance the comparison ability of the relationship module by mining potential relationships among support classes. SLTRN demonstrates comparable performance with state-of-the-art methods on benchmarks, particularly excelling in the 1-shot setting with 52.11% and 67.55% accuracy on miniImageNet and CUB, respectively. Extensive ablation experiments validate the effectiveness and optimal settings of SLTRN. The experimental code for this work is available at https://github.com/ZitZhengWang/SLTRN.
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Redes Neurais de Computação , Algoritmos , Benchmarking , Aprendizado de MáquinaRESUMO
The dual filial piety model divides filial piety beliefs into two types: reciprocal and authoritarian filial piety beliefs (RFP vs. AFP) in terms of attitude, emotion, and obligation towards parents. Previous studies have shown that these two types of filial piety beliefs related to different psychological outcomes. Literature also suggests that some aspects of the function of filial piety beliefs may be a cultural universal. This research aimed to test the effects of filial piety beliefs on aggression using participants from two cultures (Chinese vs. Islamic). We further explored the mediating role of moral disengagement, forgiveness, and self-control between filial piety beliefs and aggression, and the moderating role of culture. The results showed that moral disengagement, forgiveness, and self-control played mediating roles in the relationship between filial piety beliefs and aggression. The functions of filial piety beliefs showed both similarities and differences across cultures. (1) RFP was negatively associated with aggression in both cultures, while AFP was negatively associated with aggression only among Muslim participants. (2) RFP can reduce the aggression of Chinese participants through moral disengagement, forgiveness, and self-control; while the RFP of Muslim participants can reduce their aggressiveness only through forgiveness. (3) AFP enhanced aggression via moral disengagement and reduced self-control among; Chinese participants, but reduced aggression via self-control among Muslim participants. Findings of this study confirmed that the functions of RFP show more similarities than differences across cultures, while functions of AFP do the opposite.
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Recently, bulky alkaline earth (Ae=Mg, Ca, Sr, Ba) metal amide complexes AeN"2 (N"=N[Si(iPr)3]2) are shown to be active for catalyzing the hydrogenation of unactivated alkenes and arenes, presumably via the monomer N"AeH as catalyst. In sharp contrast, our extensive DFT calculations disclose that the double Ae-H-Ae bridged dimer (N"AeH)2 is kinetically more favorable in catalytic hydrogenation with H2, although rate-limited by the initial hydrogenolysis of AeN"2 to form the monomer N"AeH.
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B(C6F5)3 and the corresponding anion [B(C6F5)4]- are ubiquitous in main group and transition metal chemistry. Known derivatives are generally limited to the incorporation of electron donating substituents. Herein we describe electrophilic fluorination and dearomatization of such species using XeF2 in the presence of BF3 or Lewis acidic cations. In this fashion the anions [HB(C6F5)3]-, [B(C6F5)4]- and [(C6F5)3BC≡NB(C6F5)3]-, are converted to [FB(C6F7)3]-, [B(C6F7)4]-, and [(C6F7)3BC≡NB(C6F7)3]-, respectively. Similarly, the borane adducts (L)B(C6F7)3 (L=MeCN, OPEt3) are produced. These rare examples of electrophilic attack of electron deficient rings proceed as [XeF][BF4] acts as a frustrated Lewis pair effecting fluorination and dearomatization of C6F5 rings.
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The long-term effects of the Central Atlantic Magmatic Province, a large igneous province connected to the end-Triassic mass-extinction (201.5 Ma), remain largely elusive. Here, we document the persistence of volcanic-induced mercury (Hg) pollution and its effects on the biosphere for ~1.3 million years after the extinction event. In sediments recovered in Germany (Schandelah-1 core), we record not only high abundances of malformed fern spores at the Triassic-Jurassic boundary, but also during the lower Jurassic Hettangian, indicating repeated vegetation disturbance and stress that was eccentricity-forced. Crucially, these abundances correspond to increases in sedimentary Hg-concentrations. Hg-isotope ratios (δ202Hg, Δ199Hg) suggest a volcanic source of Hg-enrichment at the Triassic-Jurassic boundary but a terrestrial source for the early Jurassic peaks. We conclude that volcanically injected Hg across the extinction was repeatedly remobilized from coastal wetlands and hinterland areas during eccentricity-forced phases of severe hydrological upheaval and erosion, focusing Hg-pollution in the Central European Basin.
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Extinção Biológica , Gleiquênias , Fósseis , Sedimentos Geológicos , Mercúrio , Mercúrio/análise , Sedimentos Geológicos/química , Alemanha , Erupções Vulcânicas , Mutagênese , Clima , EsporosRESUMO
We describe a highly stereoconvergent radical epoxide allylation towards diastereomerically and enantiomerically enriched α-quaternary alcohols in two steps from olefins. Our approach combines the stereospecifity and enantioselectivity of the Shi epoxidation with the unprecedented Ti(III)-promoted intramolecular radical group transfer allylation of epoxides. A directional isomerization step via configurationally labile radical intermediates enables the selective preparation of all-carbon quaternary stereocenters in a unique fashion.
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Background: Severe traumatic brain injuries (TBIs) are an important health issue worldwide, which are associated with harmful side effects. This meta-analysis investigates the cognitive and functional outcomes in severe brain trauma cases. It assesses the impact on memory, verbal and visual abilities, attention, learning, and the presence of depression. The study provides a comprehensive overview of the consequences of severe brain trauma injury on cognitive and functional domains. Objective: The main objective of the current comprehensive meta-analysis study is to assess and analyze the impact of severe TBI on functional and cognitive outcomes, including verbal, visual, attention, learning, memory, and emotional stability. Methods: We collected data from three online databases, including PubMed, Cochrane Library, and Embase. Case-control trials related to severe TBI association with cognitive and functional outcomes were included. Verbal strength, visual functions, learning abilities, attention, memory, and depression were considered primary outcomes. Results: We have included 13 case-control studies with 1,442 subjects in this meta-analysis, which provide adequate data to determine the pooled effect size for targeted outcomes. The effect of severe TBI on the inducement of depression and impairment of memory, verbal, visual, attention, and learning abilities compared to the control group showed statistically significant outcomes (p < 0.05). Conclusion: Severe TBI is strongly associated with impaired cognitive and functional abilities, including visual and verbal disabilities, impaired memory, depression inducement, attention deficits, and learning disabilities.
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The mid-Proterozoic, spanning 1.8 to 0.8 billion years ago, is recognized as a phase of marine anoxia, low marine primary productivity (MPP), and constrained eukaryotic biodiversity. However, emerging evidence suggesting intermittent environmental disturbances and concurrent eukaryotic evolution challenges the notion of a stagnant Earth during this era. We present a study detailing volcanic activity and its consequential impact on terrestrial weathering and MPP, elucidated through the examination of 1.4-billion-year-old tropical offshore sediments. Our investigation, leveraging precise mercury (Hg) and lithium (Li) isotopic analyses, reveals the introduction of fresh rock substrates by local volcanism. This geological event initiated a transformative process, shifting the initial regolith-dominated condition in tropical lowland to a regime of enhanced chemical weathering and denudation efficiency. Notably, the heightened influx of nutrient-rich volcanic derivatives, especially phosphorus, spurred MPP rates and heightened organic carbon burial. These factors emerge as potential drivers in breaking the long-term static state of the mid-Proterozoic.
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Actinidia arguta, the most widely distributed Actinidia species and the second cultivated species in the genus, can be distinguished from the currently cultivated Actinidia chinensis on the basis of its small and smooth fruit, rapid softening, and excellent cold tolerance. Adaptive evolution of tetraploid Actinidia species and the genetic basis of their important agronomic traits are still unclear. Here, we generated a chromosome-scale genome assembly of an autotetraploid male A. arguta accession. The genome assembly was 2.77 Gb in length with a contig N50 of 9.97 Mb and was anchored onto 116 pseudo-chromosomes. Resequencing and clustering of 101 geographically representative accessions showed that they could be divided into two geographic groups, Southern and Northern, which first diverged 12.9 million years ago. A. arguta underwent two prominent expansions and one demographic bottleneck from the mid-Pleistocene climate transition to the late Pleistocene. Population genomics studies using paleoclimate data enabled us to discern the evolution of the species' adaptation to different historical environments. Three genes (AaCEL1, AaPME1, and AaDOF1) related to flesh softening were identified by multi-omics analysis, and their ability to accelerate flesh softening was verified through transient expression assays. A set of genes that characteristically regulate sexual dimorphism located on the sex chromosome (Chr3) or autosomal chromosomes showed biased expression during stamen or carpel development. This chromosome-level assembly of the autotetraploid A. arguta genome and the genes related to important agronomic traits will facilitate future functional genomics research and improvement of A. arguta.
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Actinidia , Genoma de Planta , Tetraploidia , Actinidia/genética , Evolução Molecular , Adaptação Fisiológica/genética , Evolução BiológicaRESUMO
BACKGROUND: As the burden of mental disorders among patients with atrial fibrillation (AF) increases, researchers are beginning to pay close attention to the risk and prevalence of these comorbidities. Although studies have independently analyzed the risk of comorbidity with depression and anxiety in patients with AF, no study has systematically focused on the global epidemiology of these two mental disorders. AIM: To explore the prevalence of depression and anxiety in patients with AF. METHODS: Five databases were searched from their date of establishment until January 2023. Observational studies reporting the comorbidity of AF with depression and anxiety, were included in this study. Basic information, such as the first author/ publication year, study year, study type, and prevalence of depression and anxiety, were extracted. STATA SE 15.1 was used to analyze the data. Subgroup, meta-regression, and sensitivity analyses were performed to estimate study heterogeneity. RESULTS: After a thorough search, 26 studies were identified and included in this meta-analysis. The prevalence rates of depression and anxiety in adults with AF were 24.3% and 14.5%, respectively. Among adult males with AF, the prevalence was 11.7% and 8.7%, respectively, whereas in females it was 19.8% and 10.1%, respectively. In older adults with AF, the prevalence rates of depression and anxiety were 40.3% and 33.6%, respectively. The highest regional prevalence of depression and anxiety was observed in European (30.2%) and North American (19.8%) patients with AF. CONCLUSION: In this study, we found that the prevalence of depression and anxiety among patients with AF varies with sex, region, and evaluation scales, suggesting the need for psychological interventions for patients with AF in clinical practice.
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Upwelling plays a pivotal role in supplying methylmercury (MeHg) to the upper oceans, contributing to the bioaccumulation of MeHg in the marine food web. However, the influence of the upwelling of Circumpolar Deep Water (CDW), the most voluminous water mass in the Southern Ocean, on the MeHg cycle in the surrounding oceans and marine biota of Antarctica remains unclear. Here, we study the mercury (Hg) isotopes in an ornithogenic sedimentary profile strongly influenced by penguin activity on Ross Island, Antarctica. Results indicate that penguin guano is the primary source of Hg in the sediments, and the mass-independent isotope fractionation of Hg (represented by Δ199Hg) can provide insights on the source of marine MeHg accumulated by penguin. The Δ199Hg in the sediments shows a significant decrease at â¼1550 CE, which is primarily attributed to the enhanced upwelling of CDW that brought more MeHg with lower Δ199Hg from the deeper seawater to the upper ocean. We estimate that the contribution of MeHg from the deeper seawater may reach more than 38% in order to explain the decline in Δ199Hg at â¼1550 CE. Moreover, we found that the intensified upwelling may have increased the MeHg exposure for marine organisms, highlighting the importance of CDW upwelling on the MeHg cycle in Antarctic coastal ecosystems.
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Mercúrio , Compostos de Metilmercúrio , Poluentes Químicos da Água , Compostos de Metilmercúrio/análise , Isótopos de Mercúrio/análise , Regiões Antárticas , Ecossistema , Água , Monitoramento Ambiental/métodos , Mercúrio/análise , Oceanos e Mares , Cadeia Alimentar , Poluentes Químicos da Água/análiseRESUMO
The phosphino-phosphenium cation (PPC) [Ph3PPPh2][GaCl4] reacts as a frustrated Lewis pair to add across the NîN bond of (tBuO2CN)2. In contrast, photolytical addition [Ph2ClPPPh2][GaCl4] to (RN)2 results in cleavage of the NîN bond affording [Ph2P(µ-NR)2PPh2Cl][GaCl4] (R = Ph 2, C6H4Cl3). While the chloride of 2 is replaced with N3 or CN via reaction with Me3SiN3 or tBuNC respectively, reaction with (C6F5)2BH effects ring opening to give [HN(Ph)PPh2(µ-NPh)PPh2][GaCl4] 7. This reactivity demonstrates that PPCs behave as FLPs to effect either addition or cleavage of NîN double bonds.
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Chemodynamic therapy based on the Fenton reaction has been developed as an extremely promising modality for cancer therapeutics. In this study, a core-shell structure nanoplatform was constructed by a Au nanorod externally encapsulating Ce/Zn-based composites (ACZO). The nanoparticles can catalyze the generation of reactive oxygen species (ROS) under acidic conditions and effectively consume existing glutathione (GSH) to destroy the redox balance within the tumor. Moreover, the decomposition of the nanocomplexes under acidic conditions releases large amounts of zinc ions, leading to zinc overload in cancer cells. The photothermal effect generated by the Au nanorods not only provides photothermal therapy (PTT) but also augments the catalytic reaction and ions action mentioned above. This facile strategy to improve the efficacy of chemodynamic therapy by the photothermal enhancement of catalytic activity and zinc ion release provides a promising perspective for potential tumor treatment.
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Nanopartículas , Nanotubos , Neoplasias , Humanos , Catálise , Glutationa , Zinco/farmacologia , Íons , Neoplasias/tratamento farmacológico , Linhagem Celular Tumoral , Peróxido de Hidrogênio , Microambiente TumoralRESUMO
A facile and direct intramolecular indolinone-quinolone rearrangement was developed for the synthesis of quinolino[3,4-b]quinoxalin-6-ones from spiro[indoline-3,2'-quinoxaline]-2,3'-diones, which are readily available with use of isatines, malononitrile, and 1,2-phenylenediamines under quite mild conditions. This efficient approach provides excellent yields and could potentially be used for the construction of a diverse library of quinolino[3,4-b]quinoxalin-6-ones for high-throughput screening in medicinal chemistry. The reaction mechanism is explored by extensive DFT calculations.
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Recent reports of radical formation within frustrated Lewis pairs (FLPs) suggested that single-electron transfer (SET) could play an important role in their chemistry especially for C-C coupling. In sharp contrast, our extensive dispersion-corrected DFT calculations show that although reactive benzhydryl radical along with phosphine radical cation species can be kinetically generated from bulky phosphines and benzhydryl cation, direct P-C hetero-coupling may lead to bulky phosphonium cation as reactive carbocation transfer reagents to styrene substrates, which is kinetically much more favorable than the recently proposed radical C-C coupling between benzhydryl radical and styrene. Similarly, meta-stable radical cation Mes3 P+ â salt is also kinetically accessible via SET reactions of Mes3 P and B(C6 F5 )3 with 0.5 equivalent of p-O2 C6 Cl4 .