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1.
Brief Bioinform ; 25(3)2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38561979

RESUMO

Peptide binding to major histocompatibility complex (MHC) proteins plays a critical role in T-cell recognition and the specificity of the immune response. Experimental validation such peptides is extremely resource-intensive. As a result, accurate computational prediction of binding peptides is highly important, particularly in the context of cancer immunotherapy applications, such as the identification of neoantigens. In recent years, there is a significant need to continually improve the existing prediction methods to meet the demands of this field. We developed ConvNeXt-MHC, a method for predicting MHC-I-peptide binding affinity. It introduces a degenerate encoding approach to enhance well-established panspecific methods and integrates transfer learning and semi-supervised learning methods into the cutting-edge deep learning framework ConvNeXt. Comprehensive benchmark results demonstrate that ConvNeXt-MHC outperforms state-of-the-art methods in terms of accuracy. We expect that ConvNeXt-MHC will help us foster new discoveries in the field of immunoinformatics in the distant future. We constructed a user-friendly website at http://www.combio-lezhang.online/predict/, where users can access our data and application.


Assuntos
Peptídeos , Peptídeos/metabolismo , Ligação Proteica
2.
Angew Chem Int Ed Engl ; : e202402669, 2024 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-38637296

RESUMO

Singlet oxygen (1O2) is an essential reactive species responsible for selective oxidation of organic matter, especially in Fenton-like processes. However, due to the great limitations in synthesizing catalysts with well-defined active sites, the controllable production and practical application of 1O2 remain challenging. Herein, guided by theoretical simulations, a series of boron nitride-based single-atom catalysts (BvBN/M, M = Co, Fe, Cu, Ni and Mn) were synthesized to regulate 1O2 generation by activating peroxymonosulfate (PMS). All the fabricated BvBN/M catalysts with explicit M-N3 sites promoted the self-decomposition of the two PMS molecules to generate 1O2 with high selectivity, where BvBN/Co possessed moderate adsorption energy and d-band center exhibited superior catalytic activity. As an outcome, the BvBN/Co-PMS system coupled with membrane filtration technology could continuously transform aromatic alcohols to aldehydes with nearly 100% selectivity and conversion rate under mild conditions, suggesting the potential of this novel catalytic system for green organic synthesis.

3.
Chemosphere ; 354: 141737, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38499078

RESUMO

Extracting heavy metal ions from wastewater has significant implications for both environmental remediation and resource preservation. However, the conventional adsorbents still suffer from incomplete ion removal and low utilization efficiency of the recovered metals. Herein, we present an extraction and reutilization method assisted by porous boron nitride (p-BN) containing high-density N atoms for metal recovery with simultaneous catalyst formation. The p-BN exhibits stable and efficient metal adsorption performance, particularly for ultra-trace-level water purification. The distribution coefficients towards Pb2+, Cd2+, Co2+ and Fe3+ can exceed 106 mL g-1 and the residual concentrations that reduced from 1 mg L-1 to 0.8-1.3 µg L-1 are much lower than the acceptable limits in drinking water standards of World Health Organization. Meanwhile, the used p-BN after Co ion adsorption can be directly adopted as a high-efficiency catalyst for activating peroxymonosulfate (PMS) in organic pollutant degradation without additional post-treatment, avoiding the secondary metal pollution and the problems of neglected manpower and energy consumption. Moreover, a flow-through multistage utilization system assisted by p-BN/polyvinylidene fluoride (PVDF) membrane is constructed for achieving both metal ion separation and reutilization in the removal of organic pollutants, providing a new avenue for sustainable wastewater remediation.


Assuntos
Compostos de Boro , Poluentes Ambientais , Metais Pesados , Poluentes Químicos da Água , Águas Residuárias , Porosidade , Poluentes Químicos da Água/análise , Metais Pesados/análise , Adsorção , Íons
4.
Brief Bioinform ; 25(2)2024 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-38343322

RESUMO

Vaccination stands as the most effective and economical strategy for prevention and control of influenza. The primary target of neutralizing antibodies is the surface antigen hemagglutinin (HA). However, ongoing mutations in the HA sequence result in antigenic drift. The success of a vaccine is contingent on its antigenic congruence with circulating strains. Thus, predicting antigenic variants and deducing antigenic clusters of influenza viruses are pivotal for recommendation of vaccine strains. The antigenicity of influenza A viruses is determined by the interplay of amino acids in the HA1 sequence. In this study, we exploit the ability of convolutional neural networks (CNNs) to extract spatial feature representations in the convolutional layers, which can discern interactions between amino acid sites. We introduce PREDAC-CNN, a model designed to track antigenic evolution of seasonal influenza A viruses. Accessible at http://predac-cnn.cloudna.cn, PREDAC-CNN formulates a spatially oriented representation of the HA1 sequence, optimized for the convolutional framework. It effectively probes interactions among amino acid sites in the HA1 sequence. Also, PREDAC-CNN focuses exclusively on physicochemical attributes crucial for the antigenicity of influenza viruses, thereby eliminating unnecessary amino acid embeddings. Together, PREDAC-CNN is adept at capturing interactions of amino acid sites within the HA1 sequence and examining the collective impact of point mutations on antigenic variation. Through 5-fold cross-validation and retrospective testing, PREDAC-CNN has shown superior performance in predicting antigenic variants compared to its counterparts. Additionally, PREDAC-CNN has been instrumental in identifying predominant antigenic clusters for A/H3N2 (1968-2023) and A/H1N1 (1977-2023) viruses, significantly aiding in vaccine strain recommendation.


Assuntos
Vírus da Influenza A Subtipo H1N1 , Vírus da Influenza A , Vacinas , Vírus da Influenza A/genética , Vírus da Influenza A Subtipo H3N2/genética , Glicoproteínas de Hemaglutininação de Vírus da Influenza/genética , Estações do Ano , Estudos Retrospectivos , Antígenos Virais/genética , Redes Neurais de Computação , Aminoácidos
5.
IEEE Trans Vis Comput Graph ; 30(1): 1117-1127, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37874716

RESUMO

Livestream e-commerce integrates live streaming and online shopping, allowing viewers to make purchases while watching. However, effective marketing strategies remain a challenge due to limited empirical research and subjective biases from the absence of quantitative data. Current tools fail to capture the interdependence between live performances and feedback. This study identified computational features, formulated design requirements, and developed LiveRetro, an interactive visual analytics system. It enables comprehensive retrospective analysis of livestream e-commerce for streamers, viewers, and merchandise. LiveRetro employs enhanced visualization and time-series forecasting models to align performance features and feedback, identifying influences at channel, merchandise, feature, and segment levels. Through case studies and expert interviews, the system provides deep insights into the relationship between live performance and streaming statistics, enabling efficient strategic analysis from multiple perspectives.


Assuntos
Comércio , Gráficos por Computador , Estudos Retrospectivos , Pesquisa Empírica , Comportamento do Consumidor
6.
Nat Commun ; 14(1): 7841, 2023 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-38030639

RESUMO

The development of heterogenous catalysts based on the synthesis of 2D carbon-supported metal nanocatalysts with high metal loading and dispersion is important. However, such practices remain challenging to develop. Here, we report a self-polymerization confinement strategy to fabricate a series of ultrafine metal embedded N-doped carbon nanosheets (M@N-C) with loadings of up to 30 wt%. Systematic investigation confirms that abundant catechol groups for anchoring metal ions and entangled polymer networks with the stable coordinate environment are essential for realizing high-loading M@N-C catalysts. As a demonstration, Fe@N-C exhibits the dual high-efficiency performance in Fenton reaction with both impressive catalytic activity (0.818 min-1) and H2O2 utilization efficiency (84.1%) using sulfamethoxazole as the probe, which has not yet been achieved simultaneously. Theoretical calculations reveal that the abundant Fe nanocrystals increase the electron density of the N-doped carbon frameworks, thereby facilitating the continuous generation of long-lasting surface-bound •OH through lowering the energy barrier for H2O2 activation. This facile and universal strategy paves the way for the fabrication of diverse high-loading heterogeneous catalysts for broad applications.

7.
Nat Commun ; 14(1): 3414, 2023 06 09.
Artigo em Inglês | MEDLINE | ID: mdl-37296147

RESUMO

While functional MRI (fMRI) studies have mainly focused on gray matter, recent studies have consistently found that blood-oxygenation-level-dependent (BOLD) signals can be reliably detected in white matter, and functional connectivity (FC) has been organized into distributed networks in white matter. Nevertheless, it remains unclear whether this white matter FC reflects underlying electrophysiological synchronization. To address this question, we employ intracranial stereotactic-electroencephalography (SEEG) and resting-state fMRI data from a group of 16 patients with drug-resistant epilepsy. We find that BOLD FC is correlated with SEEG FC in white matter, and this result is consistent across a wide range of frequency bands for each participant. By including diffusion spectrum imaging data, we also find that white matter FC from both SEEG and fMRI are correlated with white matter structural connectivity, suggesting that anatomical fiber tracts underlie the functional synchronization in white matter. These results provide evidence for the electrophysiological and structural basis of white matter BOLD FC, which could be a potential biomarker for psychiatric and neurological disorders.


Assuntos
Substância Branca , Humanos , Substância Branca/fisiologia , Substância Cinzenta/fisiologia , Imageamento por Ressonância Magnética/métodos , Eletroencefalografia , Imagem de Difusão por Ressonância Magnética , Encéfalo/diagnóstico por imagem , Encéfalo/fisiologia , Mapeamento Encefálico
8.
Front Immunol ; 14: 1123652, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36825001

RESUMO

Introduction: Central nervous system (CNS) diseases, such as neurodegenerative disorders and brain diseases caused by acute injuries, are important, yet challenging to study due to disease lesion locations and other complexities. Methods: Utilizing the powerful method of spatial transcriptome analysis together with novel algorithms we developed for the study, we report here for the first time a 3D trajectory map of gene expression changes in the brain following acute neural injury using a mouse model of intraventricular hemorrhage (IVH). IVH is a common and representative complication after various acute brain injuries with severe mortality and mobility implications. Results: Our data identified three main 3D global pseudospace-time trajectory bundles that represent the main neural circuits from the lateral ventricle to the hippocampus and primary cortex affected by experimental IVH stimulation. Further analysis indicated a rapid response in the primary cortex, as well as a direct and integrated effect on the hippocampus after IVH stimulation. Discussion: These results are informative for understanding the pathophysiological changes, including the spatial and temporal patterns of gene expression changes, in IVH patients after acute brain injury, strategizing more effective clinical management regimens, and developing novel bioinformatics strategies for the study of other CNS diseases. The algorithm strategies used in this study are searchable via a web service (www.combio-lezhang.online/3dstivh/home).


Assuntos
Lesões Encefálicas , Neoplasias Encefálicas , Humanos , Hemorragia Cerebral/etiologia , Encéfalo/metabolismo , Lesões Encefálicas/genética , Perfilação da Expressão Gênica , Hematoma/etiologia
9.
Inquiry ; 59: 469580221128735, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36217738

RESUMO

Insight into the current status of long-term care facilities (LTCFs) and chronic diseases in underdeveloped areas in China is scant. Using a census method to survey older adults ≥60 years old (154 older adult residents) in all LTCFs in Jishou area. The International Resident Assessment Instrument for Long-Term Care Facilities (interRAI-LTCF) was used to collect information and analyze the current status of chronic diseases among older adult residents. There were 62 187 residents ≥60 years old in Jishou area. According to the survey, there were only 154 older adult residents living in the LTCFs of Jishou, with a ratio was 0.3% of all older adult residents, which was much lower than China's 3.0%. Of respondents (109 older adult residents), the prevalence of chronic diseases was 70.6%. The prevalence increases with age, as well as in the female is higher than in the male. The top 3 chronic diseases were hypertension (41.3%), bone and joint disease (12.8%) and cerebrovascular disease (12.8%). It was found that different age groups and genders lead to differences in the prevalence and the order of chronic diseases. The prevalence of older adults with impaired balance ability, sleep disturbance and swallowing disturbance was higher than that of normal older adults. The results of the one-way analysis of variance showed that the age and balance ability of the older adults with chronic diseases were statistically significant (P < .05). In addition, the prevalence of chronic diseases in the LTCFs older adult was higher than the home care (HC) older adults in Jishou. The age and the prevalence of chronic diseases of LTCFs in older adults with professional nursing staff were higher than in those without. This study provides a theoretical basis for the healthcare distribution, prevention and treatment of chronic diseases in underdeveloped areas. The undeveloped area has lower LTCFs staying rate and chronic disease prevalence of older adults than relatively developed areas. More public health attention and capital investment are needed to increase the LTCFs number and strengthen disease testing and screening. As well as, the proportion of professional nursing staff and specialist doctors in LTCFs and improve the quality of care and medical treatment for older adults.


Assuntos
Assistência de Longa Duração , Casas de Saúde , Idoso , Doença Crônica , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Inquéritos e Questionários
10.
Chemosphere ; 294: 133704, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35066083

RESUMO

Developing Fe-based catalysts with high-effective and environmentally friendly features in Fenton-like system for treating wastewater is still a challenge. Novel nitrogen-doped carbon nanosheets with Fe0/Fe3C nano-particles (Fe@NCS-900) were prepared through a simple solvent-free strategy by pyrolyzing the mixture of 2,6-diaminopyridine and ferric chloride hexahydrate under 900 °C. The Fe@NCS-900 possessed almost 100% removal efficiency and 66.5% mineralization rate for the degradation of CBZ in 10 min. Moreover, the Fe@NCS-900 exhibited an apparent first-order constant as high as 0.8809 min-1, which is 22 and 29 times higher than that of the commercial Fe0 and traditional Fenton system, respectively, which could be attribute to the high graphitization degree and rich nitrogen content. Besides, the results of the radical quenching experiments, electron paramagnetic resonance (EPR) and the probe experiments demonstrated that a large number of high valent iron species (Fe (IV)) besides singlet oxygen (1O2) and superoxide radicals (O2•-) existed and contributed to the CBZ degradation. More interestingly, the addition of coexisting anion SO42- in the reaction system could significantly boost the concentration of •OH and SO4•- by 28.3 times and 9.7 times, respectively, resulting in the increase of the apparent first-order constant by 5.9 times (5.1733 min-1), which was entirely different from previous reports that SO42- had no effect on the catalytic activity or even displayed slightly inhibitory effect. In addition, the catalyst exhibited broad pH adaptability in the pH range of 2-9. The intermediate products of CBZ degradation were investigated by liquid chromatography mass spectrometry (LC-MS) and the degradation pathway was proposed. This paper provides new insights for developing a promising Fe-based nitrogen-doped catalyst for practical wastewater treatment.


Assuntos
Carbono , Nanopartículas , Antibacterianos , Nitrogênio , Peróxidos/química , Sulfatos
11.
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi ; 34(4): 602-605, 2017 08 25.
Artigo em Chinês | MEDLINE | ID: mdl-29745559

RESUMO

In order to address the problem of traditional dolphin adjuvant therapy such as high cost and its limitation in time and place, this paper introduces a three-dimensional virtual dolphin adjuvant therapy system based on virtual reality technology. By adopting Oculus wearable three-dimensional display, the system combined natural human-computer interaction based on Leap Motion with high-precision gesture recognition and cognitive training, and achieved immersive three-dimensional interactive game for child rehabilitation training purposes. The experimental data showed that the system can effectively improve the cognitive and social abilities of those children with autism spectrum disorder, providing a useful exploration for the rehabilitation of those children.

12.
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi ; 23(5): 1024-7, 2006 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-17121346

RESUMO

Osteotomies were performed through post-lateral approach under the base of femoral neck on 60 New Zealand white rabbits. The changes of the thickness and biomechanical properties of acetabular cartilage following the cartilage degeneration and the relationship to the postoperative time 2, 4, 6, 8, 12, 16 weeks later were measured respectively. The cartilage specimens were harvested and measured by the automated creep indentation apparatus to obtain the thickness and biomechanical properties. The cartilage became thicker within 6 weeks after operation, cartilage degeneration developed critically from the surface with the lost of the biomechanical properties. The degeneration progressed till the eartilage became thinner and thinner and the to be torn out into pieces at last. The matrix of articular cartilage degraded markedly for the absence of normal stress load following the femoral neck fracture, led to the decline of the biomechanical properties and kept the degeneration progress to osteoarthritis.


Assuntos
Cartilagem Articular/fisiopatologia , Fraturas do Colo Femoral/fisiopatologia , Animais , Fenômenos Biomecânicos , Cartilagem Articular/patologia , Modelos Animais de Doenças , Elasticidade , Feminino , Fraturas do Colo Femoral/patologia , Masculino , Coelhos , Estresse Mecânico , Fatores de Tempo
13.
Chin J Traumatol ; 5(3): 172-5, 2002 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12034082

RESUMO

OBJECTIVE: To provide theoretical basis for effect and mechanism of percutaneous lumbar discectomy in clinic. METHODS: A total of 180 patients with lumbar intervertebral disc herniation were evaluated by CT on the fifth day before and after operation. Meanwhile, CT value was measured in the determined level and region. RESULTS: After operation, CT value of the central and posterior determined point of herniated intervertebral disc was lower significantly than that before operation (P<0.01), but CT value of the anterior determined point was different insignificantly. The excellent and good results of the patients together were 83% postoperatively. CONCLUSIONS: The curative effect of percutaneous lumbar discectomy is achieved through reduction of lumbar intradiscal pressure.


Assuntos
Discotomia Percutânea , Deslocamento do Disco Intervertebral/diagnóstico por imagem , Deslocamento do Disco Intervertebral/cirurgia , Vértebras Lombares , Tomografia Computadorizada por Raios X , Adulto , Feminino , Humanos , Vértebras Lombares/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento
14.
Artigo em Chinês | MEDLINE | ID: mdl-12569695

RESUMO

OBJECTIVE: To investigate surgical reconstruction of stability of lower cervical spine in children suffering trauma, tuberculosis and tumor. METHODS: From January 1998 to September 2001, 8 cases of unstable lower cervical spine were treated by operations, of anterior decompression, massive iliac bone grafting, posterior fixation with spinous process tension band wiring, and fusion with heterogeneous iliac bone grafting. RESULTS: With an average following up of 1 year and 9 months (6 months to 4 years and 3 months), 3 cases recovered excellently, 4 cases recovered well and 1 case died of pulmonary infection. CONCLUSION: The above results indicate that anterior decompression, massive iliac bone grafting, posterior fixation with spinous process tension band wiring and fusion with heterogeneous iliac bone grafting can be used as one of the methods to reconstruct the stability of lower cervical spine in children.


Assuntos
Vértebras Cervicais/cirurgia , Ílio/transplante , Procedimentos de Cirurgia Plástica , Compressão da Medula Espinal/cirurgia , Traumatismos da Coluna Vertebral/cirurgia , Criança , Pré-Escolar , Descompressão Cirúrgica , Feminino , Fixação Interna de Fraturas , Humanos , Masculino , Compressão da Medula Espinal/etiologia
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