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1.
Adv Sci (Weinh) ; : e2402838, 2024 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-38896788

RESUMO

Chemoselective modification of specific residues within a given protein poses a significant challenge, as the microenvironment of amino acid residues in proteins is variable. Developing a universal molecular platform with tunable chemical warheads can provide powerful tools for precisely labeling specific amino acids in proteins. Cysteine and lysine are hot targets for chemoselective modification, but current cysteine/lysine-selective warheads face challenges due to cross-reactivity and unstable reaction products. In this study, a versatile fluorescent platform is developed for highly selective modification of cysteine/lysine under biocompatible conditions. Chloro- or phenoxy-substituted NBSe derivatives effectively labeled cysteine residues in the cellular proteome with high specificity. This finding also led to the development of phenoxy-NBSe phototheragnostic for the diagnosis and activatable photodynamic therapy of GSH-overexpressed cancer cells. Conversely, alkoxy-NBSe derivatives are engineered to selectively react with lysine residues in the cellular environment, exhibiting excellent anti-interfering ability against thiols. Leveraging a proximity-driven approach, alkoxy-NBSe probes are successfully designed to demonstrate their utility in bioimaging of lysine deacetylase activity. This study also achieves integrating a small photosensitizer into lysine residues of proteins in a regioselective manner, achieving photoablation of cancer cells activated by overexpressed proteins.

2.
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi ; 40(2): 249-256, 2023 Apr 25.
Artigo em Chinês | MEDLINE | ID: mdl-37139755

RESUMO

Hypertension is the primary disease that endangers human health. A convenient and accurate blood pressure measurement method can help to prevent the hypertension. This paper proposed a continuous blood pressure measurement method based on facial video signal. Firstly, color distortion filtering and independent component analysis were used to extract the video pulse wave of the region of interest in the facial video signal, and the multi-dimensional feature extraction of the pulse wave was preformed based on the time-frequency domain and physiological principles; Secondly, an integrated feature selection method was designed to extract the universal optimal feature subset; After that, we compared the single person blood pressure measurement models established by Elman neural network based on particle swarm optimization, support vector machine (SVM) and deep belief network; Finally, we used SVM algorithm to build a general blood pressure prediction model, which was compared and evaluated with the real blood pressure value. The experimental results showed that the blood pressure measurement results based on facial video were in good agreement with the standard blood pressure values. Comparing the estimated blood pressure from the video with standard blood pressure value, the mean absolute error (MAE) of systolic blood pressure was 4.9 mm Hg with a standard deviation (STD) of 5.9 mm Hg, and the MAE of diastolic blood pressure was 4.6 mm Hg with a STD of 5.0 mm Hg, which met the AAMI standards. The non-contact blood pressure measurement method based on video stream proposed in this paper can be used for blood pressure measurement.


Assuntos
Determinação da Pressão Arterial , Hipertensão , Humanos , Algoritmos , Pressão Sanguínea/fisiologia , Determinação da Pressão Arterial/métodos , Hipertensão/diagnóstico
3.
ACS Biomater Sci Eng ; 8(9): 3659-3675, 2022 09 12.
Artigo em Inglês | MEDLINE | ID: mdl-36037313

RESUMO

Cardiac patches are biomaterials that can be used for transplantation and repair of damaged myocardium by combining seed cells with the ability to form cardiomyocytes and suitable scaffold materials. On the one hand, they provide temporary support to the infarcted area, and on the other hand, they repair the damaged myocardium by delivering cells or bioactive factors to integrate with the host, which have gradually become a hot research topic in recent years. This paper summarizes the structural properties of natural myocardium and reviews the recent research progress of cardiac patches, including the seed cells and scaffold materials used in patch preparation, as well as the main methods of scaffold preparation and the structure properties of various scaffolds. In addition, a comprehensive analysis of the problems faced in the clinical implementation of cardiac patches is presented. Finally, we look forward to the development of cardiac patches and point out that precisely tunable anisotropic tissue engineering scaffolds close to natural myocardial tissue will become an important direction for future research.


Assuntos
Engenharia Tecidual , Alicerces Teciduais , Materiais Biocompatíveis/uso terapêutico , Miocárdio , Engenharia Tecidual/métodos , Alicerces Teciduais/química
4.
J Colloid Interface Sci ; 627: 81-89, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35841711

RESUMO

Fabrication of efficient heterogeneous catalysts with high turnover frequency (TOF) is intriguing for rapid and scalable CO2 conversion under mild conditions, but it still faces some challenges due to use of some bulky and irregular supports causing inaccessible inner pores and insufficient utilization of active sites. Herein, using a unique nitrogen-doped mesoporous single-crystal carbon (named IRFC) as a host for loading Ag nanoparticles for the first time, a series of Ag/IRFC catalysts with high TOF (8.7-22.3 h-1) were facilely prepared by a novel "impregnation and in-situ reduction" strategy. The neat morphology and high porosity of IRFC with abundant N species, providing homogeneous surface, adequate space and anchoring sites for Ag immobilization, greatly facilitated the formation of highly-distributed ultrasmall Ag nanoparticles (2.3 nm). Meanwhile, smooth and short diffusion pathways were inherited from the ordered mesopores and small particle sizes of IRFC. Owing to these unparalleled structural features, the Ag/IRFC catalysts exhibited excellent catalytic activity, stability, and generality for mild CO2 conversion even under diluted conditions. This work not only presents a novel catalyst for mild CO2 conversion, but also brings some inspirations to designing highly efficient catalysts using well-shaped supporting nanomaterials for direct utilization of low-concentration CO2, such as flue gas.

5.
ChemSusChem ; 13(2): 360-368, 2020 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-31675183

RESUMO

CO2 capture is an enabling technology for carbon conversion and storage; however, the high costs of the process have hindered its large-scale application so far. Therefore, new approaches for carbon abatement, particularly from diluted sources, are urgently needed. Herein, based on the adsorption and catalysis bifunctionality of 2D-layered Ni-O-Al2 O3 nanosheets, a two-step "capture and methanation" process is reported for the removal and utilization of CO2 , with no additional energy input for desorption being required. Continuous and nearly 100 % capture of CO2 was demonstrated at low temperatures (≤250 °C) and prolonged cycles. At isothermal conditions, the material could be fully regenerated with the production of methane, showing considerably higher time efficiency than temperature-swing and pressure-swing technologies. This strategy may pave a new way for CO2 reduction, providing a scalable connection between the power grid and the gas grid when H2 is used.

6.
Comp Biochem Physiol B Biochem Mol Biol ; 157(4): 415-22, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20851206

RESUMO

Sox genes, a family of genes related to the mammalian sex-determining region Y (SRY) gene, are found throughout the animal kingdom, and involved in diverse developmental processes including sex determination and neurogenesis. Previously, we have identified one sox11 homologue, sox11b, from the ovary of the orange-spotted grouper. In the present study, another sox11 homologue, sox11a, was cloned from the brain. The orange-spotted grouper Sox11a contained the signature features of mammalian SOX11 homologues except the Pro-Glu rich region, was clustered with Sox11a homologues of other teleosts in the phylogenetic tree, and shared higher homologies with Sox11 of other species than the duplicated copy Sox11b. Interestingly, significant conservation was observed in the 3'UTR of sox11a but not sox11b transcripts when compared with mammalian Sox11 homologues. The expression of sox11a mRNA was detected in a wide range of tissues, with higher abundances in the central nervous system. During embryogenesis and larval development, the expression of sox11a mRNA remained at considerably high levels at all stages examined, from newly fertilized eggs, through organogenesis, to the larvae 18days posthatching. Together, these results indicated that the orange-spotted grouper sox11a was evolutionarily more conserved than sox11b, and may play important roles in neurogenesis, embryogenesis, and larval development.


Assuntos
Proteínas de Peixes/genética , Perciformes/genética , Fatores de Transcrição SOXC/genética , Regiões 3' não Traduzidas , Sequência de Aminoácidos , Animais , Sequência de Bases , Sequência Conservada , Embrião não Mamífero/metabolismo , Proteínas de Peixes/classificação , Proteínas de Peixes/metabolismo , Dados de Sequência Molecular , Perciformes/embriologia , Perciformes/metabolismo , Filogenia , RNA Mensageiro/metabolismo , Fatores de Transcrição SOXC/classificação , Fatores de Transcrição SOXC/metabolismo , Alinhamento de Sequência , Distribuição Tecidual
7.
J Steroid Biochem Mol Biol ; 92(1-2): 39-50, 2004 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-15544929

RESUMO

The cDNA sequences encoding two distinct cytochrome P450 aromatases, namely P450aromB and P450aromA, were isolated from brain and ovary cDNA libraries of the orange-spotted grouper, respectively. The P450aromB cDNA consists of 1892 bp, and the open reading frame (ORF) encodes a putative protein of 506 amino acids. The P450aromA cDNA consists of 1836 bp, and the ORF encodes a putative protein of 518 amino acids. Northern blot analysis revealed a transcript of about 1.9 kb for P450aromB in the brain and kidney, and 2.1 kb for P450aromA in the ovary. The expression of both P450aromB and P450aromA genes in different tissues was further examined using one-step RT-PCR followed by Southern blot analysis. High levels of P450aromB mRNA expression were detected in the olfactory bulb, forebrain, midbrain, hypothalamus, medulla, pituitary, gill filament, gill arch, kidney, muscle, adipose tissue, and blood cells, but low levels in the hindbrain and ovary. High levels of P450aromA mRNA expression were detected in the ovary, pituitary, gill filament, gill arch, and spleen, but low levels in the forebrain, hindbrain, hypothalamus, and blood cells. In addition, the expression of P450arom genes in the orange-spotted grouper of different gonadal stages as induced by 17 alpha-methyltestosterone (MT) was investigated. The mRNA expression of P450aromB in the hypothalamus was highest in the intersexual stage, whereas the mRNA expression of P450aromA in the gonads was highest in the female stage, decreased in the intersexual stage, and lowest in the male stage. Results from current study indicate that P450aromB and P450aromA genes of the orange-spotted grouper have distinct tissue patterns of mRNA expression, and both of them may be involved in the MT-induced sex change.


Assuntos
Aromatase/genética , Aromatase/metabolismo , Regulação Enzimológica da Expressão Gênica , Perciformes/genética , Perciformes/metabolismo , Sequência de Aminoácidos , Animais , DNA Complementar/genética , DNA Complementar/metabolismo , Feminino , Regulação da Expressão Gênica no Desenvolvimento , Masculino , Dados de Sequência Molecular , Especificidade de Órgãos , Perciformes/crescimento & desenvolvimento , Filogenia , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Alinhamento de Sequência , Homologia de Sequência de Aminoácidos , Maturidade Sexual/genética
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