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1.
bioRxiv ; 2024 Aug 01.
Article in English | MEDLINE | ID: mdl-39131360

ABSTRACT

The ability to precisely target specific motifs on disease-related proteins, whether conserved epitopes on viral proteins, intrinsically disordered regions within transcription factors, or breakpoint junctions in fusion oncoproteins, is essential for modulating their function while minimizing off-target effects. Current methods struggle to achieve this specificity without reliable structural information. In this work, we introduce a motif-specific PPI targeting algorithm, moPPIt, for de novo generation of motif-specific peptide binders from the target protein sequence alone. At the core of moPPIt is BindEvaluator, a transformer-based model that interpolates protein language model embeddings of two proteins via a series of multi-headed self-attention blocks, with a key focus on local motif features. Trained on over 510,000 annotated PPIs, BindEvaluator accurately predicts target binding sites given protein-protein sequence pairs with a test AUC > 0.94, improving to AUC > 0.96 when fine-tuned on peptide-protein pairs. By combining BindEvaluator with our PepMLM peptide generator and genetic algorithm-based optimization, moPPIt generates peptides that bind specifically to user-defined residues on target proteins. We demonstrate moPPIt's efficacy in computationally designing binders to specific motifs, first on targets with known binding peptides and then extending to structured and disordered targets with no known binders. In total, moPPIt serves as a powerful tool for developing highly specific peptide therapeutics without relying on target structure or structure-dependent latent spaces.

2.
CNS Neurosci Ther ; 30(8): e14903, 2024 Aug.
Article in English | MEDLINE | ID: mdl-39139089

ABSTRACT

INTRODUCTION: Excessive neuroinflammation, apoptosis, glial scar, and demyelination triggered by spinal cord injury (SCI) are major obstacles to SCI repair. Fucoidan, a natural marine plant extract, possesses broad-spectrum anti-inflammatory and immunomodulatory effects and is regarded as a potential therapeutic for various diseases, including neurological disorders. However, its role in SCI has not been investigated. METHODS: In this study, we established an SCI model in mice and intervened in injury repair by daily intraperitoneal injections of different doses of fucoidan (10 and 20 mg/kg). Concurrently, primary oligodendrocyte precursor cells (OPCs) were treated in vitro to validate the differentiation-promoting effect of fucoidan on OPCs. Basso Mouse Scale (BMS), Louisville Swim Scale (LSS), and Rotarod test were carried out to measure the functional recovery. Immunofluorescence staining, and transmission electron microscopy (TEM) were performed to assess the neuroinflammation, apoptosis, glial scar, and remyelination. Western blot analysis was conducted to clarify the underlying mechanism of remyelination. RESULTS: Our results indicate that in the SCI model, fucoidan exhibits significant anti-inflammatory effects and promotes the transformation of pro-inflammatory M1-type microglia/macrophages into anti-inflammatory M2-type ones. Fucoidan enhances the survival of neurons and axons in the injury area and improves remyelination. Additionally, fucoidan promotes OPCs differentiation into mature oligodendrocytes by activating the PI3K/AKT/mTOR pathway. CONCLUSION: Fucoidan improves SCI repair by modulating the microenvironment and promoting remyelination.


Subject(s)
Mice, Inbred C57BL , Polysaccharides , Recovery of Function , Remyelination , Spinal Cord Injuries , Animals , Polysaccharides/pharmacology , Mice , Spinal Cord Injuries/drug therapy , Spinal Cord Injuries/pathology , Remyelination/drug effects , Remyelination/physiology , Recovery of Function/drug effects , Oligodendrocyte Precursor Cells/drug effects , Female , Cellular Microenvironment/drug effects
3.
Int J Mol Sci ; 25(16)2024 Aug 16.
Article in English | MEDLINE | ID: mdl-39201628

ABSTRACT

Water scarcity is a major environmental constraint on plant growth in arid regions. Soluble sugars and amino acids are essential osmolytes for plants to cope with osmotic stresses. Sweet sorghum is an important bioenergy crop and forage with strong adaptabilities to adverse environments; however, the accumulation pattern and biosynthesis basis of soluble sugars and amino acids in this species under osmotic stresses remain elusive. Here, we investigated the physiological responses of a sweet sorghum cultivar to PEG-induced osmotic stresses, analyzed differentially accumulated soluble sugars and amino acids after 20% PEG treatment using metabolome profiling, and identified key genes involved in the biosynthesis pathways of soluble sugars and amino acids using transcriptome sequencing. The results showed that the growth and photosynthesis of sweet sorghum seedlings were significantly inhibited by more than 20% PEG. After PEG treatments, the leaf osmotic adjustment ability was strengthened, while the contents of major inorganic osmolytes, including K+ and NO3-, remained stable. After 20% PEG treatment, a total of 119 and 188 differentially accumulated metabolites were identified in the stems and leaves, respectively, and the accumulations of soluble sugars such as raffinose, trehalose, glucose, sucrose, and melibiose, as well as amino acids such as proline, leucine, valine, serine, and arginine were significantly increased, suggesting that these metabolites should play key roles in osmotic adjustment of sweet sorghum. The transcriptome sequencing identified 1711 and 4978 DEGs in the stems, as well as 2061 and 6596 DEGs in the leaves after 20% PEG treatment for 6 and 48 h, respectively, among which the expressions of genes involved in biosynthesis pathways of sucrose (such as SUS1, SUS2, etc.), trehalose (including TPS6), raffinose (such as RAFS2 and GOLS2, etc.), proline (such as P5CS2 and P5CR), leucine and valine (including BCAT2), and arginine (such as ASS and ASL) were significantly upregulated. These genes should be responsible for the large accumulation of soluble sugars and amino acids under osmotic stresses. This study deepens our understanding of the important roles of individual soluble sugars and amino acids in the adaptation of sweet sorghum to water scarcity.


Subject(s)
Amino Acids , Gene Expression Regulation, Plant , Metabolome , Osmotic Pressure , Sorghum , Sorghum/metabolism , Sorghum/genetics , Amino Acids/metabolism , Sugars/metabolism , Gene Expression Profiling/methods , Plant Leaves/metabolism , Plant Leaves/genetics , Transcriptome , Biosynthetic Pathways , Photosynthesis
4.
ACS Nano ; 18(24): 15925-15934, 2024 Jun 18.
Article in English | MEDLINE | ID: mdl-38830113

ABSTRACT

The growth in data generation necessitates efficient data processing technologies to address the von Neumann bottleneck in conventional computer architecture. Memory-driven computing, which integrates nonvolatile memory (NVM) devices in a 3D stack, is gaining attention, with CMOS back-end-of-line (BEOL)-compatible ferroelectric (FE) diodes being ideal due to their two-terminal design and inherently selector-free nature, facilitating high-density crossbar arrays. Here, we demonstrate BEOL-compatible, high-performance FE diodes scaled to 5, 10, and 20 nm FE Al0.72Sc0.28N/Al0.64Sc0.36N films. Through interlayer (IL) engineering, we show substantial improvements in the on/off ratios (>166 times) and rectification ratios (>176 times) in these scaled devices. These characteristics also enable 5-bit multistate operation with a stable retention. We also experimentally and theoretically demonstrate the counterintuitive result that the inclusion of an IL can lead to a decrease in the ferroelectric switching voltage of the device. An in-depth analysis into the device transport mechanisms is performed, and our compact model aligns seamlessly with the experimental results. Our results suggest the possibility of using scaled AlxSc1-xN FE diodes for high-performance, low-power, embedded NVM.

5.
CNS Neurosci Ther ; 30(6): e14807, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38887853

ABSTRACT

Spinal cord injury (SCI) represents a complex pathology within the central nervous system (CNS), leading to severe sensory and motor impairments. It activates various signaling pathways, notably the mitogen-activated protein kinase (MAPK) pathway. Present treatment approaches primarily focus on symptomatic relief, lacking efficacy in addressing the underlying pathophysiological mechanisms. Emerging research underscores the significance of the MAPK pathway in neuronal differentiation, growth, survival, axonal regeneration, and inflammatory responses post-SCI. Modulating this pathway post-injury has shown promise in attenuating inflammation, minimizing apoptosis, alleviating neuropathic pain, and fostering neural regeneration. Given its pivotal role, the MAPK pathway emerges as a potential therapeutic target in SCI management. This review synthesizes current knowledge on SCI pathology, delineates the MAPK pathway's characteristics, and explores its dual roles in SCI pathology and therapeutic interventions. Furthermore, it addresses the existing challenges in MAPK research in the context of SCI, proposing solutions to overcome these hurdles. Our aim is to offer a comprehensive reference for future research on the MAPK pathway and SCI, laying the groundwork for targeted therapeutic strategies.


Subject(s)
MAP Kinase Signaling System , Spinal Cord Injuries , Spinal Cord Injuries/metabolism , Spinal Cord Injuries/therapy , Humans , Animals , MAP Kinase Signaling System/physiology , Mitogen-Activated Protein Kinases/metabolism
6.
Insect Sci ; 2024 Jun 16.
Article in English | MEDLINE | ID: mdl-38880966

ABSTRACT

The tetraspanin gene family encodes cell-surface proteins that span the membrane 4 times and play critical roles in a wide range of biological processes across numerous organisms. Recent findings highlight the involvement of a tetraspanin of the lepidopteran pest Helicoverpa armigera in resistance to Bacillus thuringiensis Cry insecticidal proteins, which are extensively used in transgenic crops. Thus, a better understanding of lepidopteran tetraspanins is urgently needed. In the current study, genome scanning in 10 lepidopteran species identified a total of 283 sequences encoding potential tetraspanins. Based on conserved cysteine patterns in the large extracellular loop and their phylogenetic relationships, these tetraspanins were classified into 8 subfamilies (TspA to TspH). Six ancestral introns were identified within lepidopteran tetraspanin genes. Tetraspanins in TspA, TspB, TspC, and TspD subfamilies exhibit highly similar gene organization, while tetraspanins in the remaining 4 subfamilies exhibited variation in intron loss and/or gain during evolution. Analysis of chromosomal distribution revealed a lepidopteran-specific cluster of 10 to 11 tetraspanins, likely formed by tandem duplication events. Selective pressure analysis indicated negative selection across all orthologous groups, with ω values ranging between 0.004 and 0.362. However, positive selection was identified at 18 sites within TspB5, TspC5, TspE3, and TspF10. Furthermore, spatiotemporal expression analysis of H. armigera tetraspanins demonstrated variable expression levels across different developmental stages and tissues, suggesting diverse functions of tetraspanin members in this globally important insect pest. Our findings establish a solid foundation for subsequent functional investigations of tetraspanins in lepidopteran species.

7.
Talanta ; 277: 126323, 2024 Sep 01.
Article in English | MEDLINE | ID: mdl-38810384

ABSTRACT

Due to its advantages of label-free and highly sensitive, the resistive pulse sensing with a nanopore has recently become even more potent for the discrimination of analytes in single molecule level. Generally, a transient interruption of ion current originated from the captured molecule passing through a nanopore will provide the rich information on the structure, charge and translocation dynamics of the analytes. Therefore, nanopore sensors have been widely used in the fields of DNA sequencing, protein recognition, and the portable detection of varied macromolecules and particles. However, the conventional nanopore devices are still lack of sufficient selectivity and sensitivity to distinguish more metabolic molecules involving ATP, glucose, amino acids and small molecular drugs because it is hard to receive a large number of identifiable signals with the fabricated pores comparable in size to small molecules for nanopore sensing. For all this, a series of innovative strategies developed in the past decades have been summarized in this review, including host-guest recognition, engineering alteration of protein channel, the introduction of nucleic acid aptamers and various delivery carriers integrating signal amplification sections based on the biological and solid nanopore platforms, to achieve the high resolution for the small molecules sensing in micro-nano environment. These works have greatly enhanced the powerful sensing capabilities and extended the potential application of nanopore sensors.


Subject(s)
Biosensing Techniques , Nanopores , Biosensing Techniques/methods , Aptamers, Nucleotide/chemistry , Proteins/analysis , Humans
8.
Int J Biometeorol ; 68(7): 1-14, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38564032

ABSTRACT

We recruited 162 healthy elderly adults to determine the thermal, physiological, and psychological effects of horticultural activities (flower arranging, transplanting, and rubble masonry) in outdoor open spaces. We linked these to local climate conditions, physiology, and comfort through a questionnaire survey. The results showed that: (1) the neutral physiological equivalent temperature (NPET) before the horticultural activities were 22.18 â„ƒ for flower arranging, 23.67 â„ƒ for transplanting, and 20.78 â„ƒ for rubble masonry, while the NPET decreased to 18.53 â„ƒ, 20.73 â„ƒ and 18.04 â„ƒ (respectively) after activities. (2) The heart rate and blood oxygen saturation changed significantly (p < 0.05) only after rubble masonry. (3) The average positive affect (PA) scores increased after flower arranging by 4.83, transplanting by 3.30, and rubble masonry by 4.00. (4) After activities, the thermal sensation vote was mainly influenced by globe temperature (41.36%), air temperature (33.47%), and wind speed (25.17%). Thermal comfort vote could be promoted because of 37.35% of an increasing positive and 21.20% of decreasing negative emotion.


Subject(s)
Heart Rate , Humans , Aged , Female , Male , Thermosensing , Temperature , Flowers , Middle Aged , Aged, 80 and over , Oxygen/blood , Emotions , Gardening
9.
Front Plant Sci ; 15: 1342814, 2024.
Article in English | MEDLINE | ID: mdl-38638357

ABSTRACT

Introduction: The severity of flood disasters is increasing due to climate change, resulting in a significant reduction in the yield and quality of forage crops worldwide. This poses a serious threat to the development of agriculture and livestock. Hemarthria compressa is an important high-quality forage grass in southern China. In recent years, frequent flooding has caused varying degrees of impacts on H. compressa and their ecological environment. Methods: In this study, we evaluated differences in flooding tolerance between the root systems of the experimental materials GY (Guang Yi, flood-tolerant) and N1291 (N201801291, flood-sensitive). We measured their morphological indexes after 7 d, 14 d, and 21 d of submergence stress and sequenced their transcriptomes at 8 h and 24 h, with 0 h as the control. Results: During submergence stress, the number of adventitious roots and root length of both GY and N1291 tended to increase, but the overall growth of GY was significantly higher than that of N1291. RNA-seq analysis revealed that 6046 and 7493 DEGs were identified in GY-8h and GY-24h, respectively, and 9198 and 4236 DEGs in N1291-8h and N1291-24h, respectively, compared with the control. The GO and KEGG enrichment analysis results indicated the GO terms mainly enriched among the DEGs were oxidation-reduction process, obsolete peroxidase reaction, and other antioxidant-related terms. The KEGG pathways that were most significantly enriched were phenylpropanoid biosynthesis, plant hormone signal transduction etc. The genes of transcription factor families, such as C2H2, bHLH and bZIP, were highly expressed in the H. compressa after submergence, which might be closely related to the submergence adaptive response mechanisms of H. compressa. Discussion: This study provides basic data for analyzing the molecular and morphological mechanisms of H. compressa in response to submergence stress, and also provides theoretical support for the subsequent improvement of submergence tolerance traits of H. compressa.

10.
Mater Today Bio ; 24: 100929, 2024 Feb.
Article in English | MEDLINE | ID: mdl-38229884

ABSTRACT

The immune microenvironment plays a pivotal role in osteoanagenesis. Biomaterials can modulate osteogenic efficacy by inducing specific local immune reactions. As 3D-printing technology advances, digital light projection printing has emerged as a promising method for creating large scale, high-precision biomaterial scaffolds. By adjusting the solid content and the sintering conditions during printing, the pore size of biomaterials can be meticulously controlled. Yet, the systematic influence of pore size on the immune microenvironment remains uncharted. We fabricated 3D-printed hydroxyapatite bioceramic scaffolds with three distinct pore sizes: 400 µm, 600 µm, and 800 µm. Our study revealed that scaffolds with a pore size of 600 µm promote macrophage M2 polarization, which is achieved by upregulating interferon-beta and HIF-1α production. When these materials were implanted subcutaneously in rats and within rabbit skulls, we observed that the 600 µm scaffolds notably improved the long-term inflammatory response, fostered vascular proliferation, and augmented new bone growth. This research paves the way for innovative therapeutic strategies for treating large segmental bone defects in clinical settings.

11.
J Ethnopharmacol ; 325: 117807, 2024 May 10.
Article in English | MEDLINE | ID: mdl-38280661

ABSTRACT

ETHNOPHARMACOLOGICAL RELEVANCE: Ulcerative colitis (UC) is a chronic, non-specific inflammatory disease affecting the colon and rectum with an etiology that remains elusive. Traditional Chinese medicine (TCM) has been widely used on long-term UC treatment to better maintain the efficacy than traditional aminosalicylic acid or glucocorticosteroids and to ease financial burden of patients. Qingchang Wenzhong Decoction (QCWZD) is a modern TCM decoction with established clinical efficacy but the mechanism of its protection on intestinal barrier function remains unclear. AIM OF THE STUDY: Current findings highlight that the activation of the hypoxia inducible factor (HIF) pathway can facilitate the repair of intestinal epithelium barrier. This study is to investigate the protective effects of QCWZD and its HIF-targeted ingredients on hypoxia-dependent intestinal barrier. METHODS: The mice model of UC was induced by dextran sulfate sodium (DSS). Disease activity index (DAI) and histopathology scores and colon length were used to measure the severity of colitis. The DAO activity in serum and protein expression of tight junction (TJ) proteins were detected to explore the function of intestinal barrier. The protein levels of HIF-1α and its downstream gene heme oxygenase-1 (HO-1) were measured as well. HIF-targeted active ingredients in QCWZD were selected by network pharmacology and molecular docking. Protective effects of six constituents on HIF-related anti-oxidative and barrier protective pathway were evaluated by lipopolysaccharide (LPS)-induced HT29 and RAW264.7 cells, through the measurement of the production of ROS and mRNA level of pro-inflammatory cytokines. HIF-1α knockdown was carried out to explore the correlation of protection effects with HIF-related pathway of the active ingredients. RESULTS: QCWZD effectively alleviated colitis induced by DSS and demonstrated a protective effect on intestinal barrier function by upregulating HIF-related pathways. Six specific ingredients in QCWZD, targeting HIF, successfully reduced the production of cellular ROS and proinflammatory cytokines in LPS-induced cells. It is noteworthy that the barrier protection provided by these molecules is intricately linked with the HIF-related pathway. CONCLUSIONS: This study elucidates the HIF-related molecular mechanism of QCWZD in protecting the function of the epithelial barrier. Six compounds targeting the activation of the HIF-dependent pathway were demonstrated to unveil a novel therapeutic approach for managing UC.


Subject(s)
Colitis, Ulcerative , Colitis , Mice , Animals , Humans , Colitis, Ulcerative/chemically induced , Colitis, Ulcerative/drug therapy , Colitis, Ulcerative/pathology , Reactive Oxygen Species , Molecular Docking Simulation , Lipopolysaccharides , Colitis/chemically induced , Cytokines/metabolism , Hypoxia
12.
Adv Mater ; 36(10): e2210455, 2024 Mar.
Article in English | MEDLINE | ID: mdl-36854170

ABSTRACT

Along with the rapid development and ever-deepening understanding of nanoscience and nanotechnology, nanomaterials hold promise to mimic the highly evolved biological exquisite nanostructures and sophisticated functions. Here, inspired by the ubiquitous antibacterial nanostructures on the wing surfaces of some insects, a NiCo2 O4 nanozyme with self-adaptive hierarchical nanostructure is developed that can capture bacteria of various morphotypes via the physico-mechanical interaction between the nanostructure and bacteria. Moreover, the developed biomimetic nanostructure further exhibits superior peroxidase-like catalytic activity, which can catalytically generate highly toxic reactive oxygen species that disrupt bacterial membranes and induce bacterial apoptosis. Therefore, the mechano-catalytic coupling property of this NiCo2 O4 nanozyme allows for an extensive and efficient antibacterial application, with no concerns of antimicrobial resistance. This work suggests a promising strategy for the rational design of advanced antibacterial materials by mimicking biological antibiosis.


Subject(s)
Biomimetic Materials , Nanostructures , Animals , Biomimetic Materials/pharmacology , Biomimetic Materials/chemistry , Peroxidases , Oxidoreductases , Anti-Bacterial Agents/pharmacology , Nanostructures/chemistry
13.
Tissue Cell ; 86: 102284, 2024 Feb.
Article in English | MEDLINE | ID: mdl-38134573

ABSTRACT

Because adenomyosis (AM) ectopic primary cells are hard to come by, have a short lifespan, and the characteristics that alter over time, their utility in AM research is constrained. This study aimed to establish a line of immortalized human adenomyosis ectopic cell (ihAMEC) to change this situation. Primary cells were obtained from AM ectopic lesion tissue and then infected with Simian Vacuolating Virus 40 Tag (SV40 T) lentivirus and screened to establish immortalized cells. We verified the main features and found that the ihAMEC could be cultured for more than 50 generations and the proliferation ability of ihAMEC was more active than that of primary cells. The cytoskeleton and cell types of ihAMEC were similar to primary cells and maintained a normal karyotype. The expression of epithelial-mesenchymal transition (EMT) markers, estrogen-metabolizing proteins, and estrogen/progesterone receptors in ihAMEC was similar to the expression seen in primary cells. In addition, the response of ihAMEC under estrogen treatment and Lipopolysaccharide intervention is similar to primary cells. The clonogenic ability of ihAMEC was lower than tumor cells and did not form tumors in tumorigenicity assays. Thus, ihAMEC can be used as in vitro cellular model for pathogenesis and drug development studies regarding AM.


Subject(s)
Adenomyosis , Female , Humans , Endometrium/pathology , Cell Line , Epithelial-Mesenchymal Transition , Estrogens , Cell Proliferation
14.
Rice (N Y) ; 16(1): 59, 2023 Dec 13.
Article in English | MEDLINE | ID: mdl-38091105

ABSTRACT

Plastid ribosomal proteins play a crucial role in the growth and development of plants, mainly in the gene expression and translation of key genes in chloroplasts. While some information is known about the regulatory processes of plastid ribosomal proteins in various plant species, there is limited knowledge about the underlying mechanisms in rice. In this study, ethyl methanesulfonate (EMS) mutagenesis was used to generate a new mutant called wlp3 (white leaf and panicle3), characterized by white or albino leaves and panicles, which exhibited this phenotype from the second leaf stage until tillering. Furthermore, after a certain period, the newly emerging leaves developed the same phenotype as the rice variety ZH11, while the albino leaves of wlp3 showed an incomplete chloroplast structure and significantly low chlorophyll content. A transition mutation (T to C) at position 380 was identified in the coding region of the LOC_Os03g61260 gene, resulting in the substitution of isoleucine by threonine during translation. WLP3 encodes the ribosomal L18 subunit, which is localized in the chloroplast. Complementation experiments confirmed that LOC_Os03g61260 was responsible for the albino phenotype in rice. WLP3 has high expression in the coleoptile, leaves at the three-leaf stage, and panicles at the heading stage. Compared to the wild-type (WT), wlp3 exhibited reduced chlorophyll synthesis and significantly decreased expression levels of genes associated with plastid development. Yeast two-hybrid (Y2H) analysis revealed that WLP3 interacts with other ribosomal subunits, to influence chloroplast development. These results contribute to a better understanding of the underlying molecular mechanisms of chloroplast development and plastid gene translation.

15.
Brain Sci ; 13(11)2023 Nov 17.
Article in English | MEDLINE | ID: mdl-38002557

ABSTRACT

BACKGROUND: Alzheimer's disease (AD) is a progressive neurodegenerative disorder with cognitive dysfunction and behavioral impairment. We aimed to use principal components factor analysis to explore the association between gait domains and AD under single and dual-task gait assessments. METHODS: A total of 41 AD participants and 41 healthy control (HC) participants were enrolled in our study. Gait parameters were measured using the JiBuEn® gait analysis system. The principal component method was used to conduct an orthogonal maximum variance rotation factor analysis of quantitative gait parameters. Multiple logistic regression was used to adjust for potential confounding or risk factors. RESULTS: Based on the factor analysis, three domains of gait performance were identified both in the free walk and counting backward assessments: "rhythm" domain, "pace" domain and "variability" domain. Compared with HC, we found that the pace factor was independently associated with AD in two gait assessments; the variability factor was independently associated with AD only in the counting backwards assessment; and a statistical difference still remained after adjusting for age, sex and education levels. CONCLUSIONS: Our findings indicate that gait domains may be used as an auxiliary diagnostic index for Alzheimer's disease.

16.
Environ Sci Technol ; 57(36): 13397-13407, 2023 09 12.
Article in English | MEDLINE | ID: mdl-37643359

ABSTRACT

Colorimetric analysis for mercury detection has great application potential in the prevention of health damage caused by mercury in the environment. Sensitivity, selectivity, and portability are core competencies of sensors, and concentrating these properties in a single sensor for efficient mercury detection remains a great challenge. Herein, a hollow structure CuS@CuSe@PVP (CCP) was prepared in which the enzyme-like activities could be activated by Hg2+ due to the antagonism between Hg and Se, inspiring the establishment of a colorimetric method for Hg2+ detection. As for Hg2+ detection performance, the linear range (LR) and limit of detection (LOD) were 1-900 and 0.81 nM in the POD-like activity system, respectively. Also, 5-550 nM of LR and 2.34 nM of LOD were achieved in the OD-like activity system. Further, a smartphone-mediated portable RGB nanosensor was fabricated, with a LOD down to 6.65 nM in the POD-like system and 7.97 nM in the OD-like system. Moreover, the excellent self-calibration and satisfactory recovery of 94.77%-106.16% were shown in the application of real water samples analysis. This study represented advanced progress toward emerging applications of nanozymes with multiple enzyme-like activities in heavy metal detection and will accelerate the development of efficient and portable heavy metal sensors.


Subject(s)
Colorimetry , Mercury , Calibration , Limit of Detection
17.
Small ; 19(43): e2301598, 2023 10.
Article in English | MEDLINE | ID: mdl-37381671

ABSTRACT

Engineered collaborative size regulation and shape engineering of multi-functional nanomaterials (NPs) offer extraordinary opportunities for improving the analysis performance. It is anticipated to address the difficulty in distinguishing color changes caused by subtle variations in target concentrations, thereby facilitating the highly sensitive analysis of lateral flow immunoassays (LFIAs). Herein, tremella-like gold-manganese oxide (Au-MnOx ) nanoparticles with precise MnCl2 regulation are synthesized as immuno signal tracers via a facile one-step redox reaction in alkaline condition at ambient temperature. Avail of the tunable elemental composition and anisotropy in morphology, black-colored tremella-like Au-MnOx exhibits superb colorimetric signal brightness, enhanced antibody coupling efficiency, marvelous photothermal performance, and unrestricted immunological recognition affinity, all of which facilitate highly sensitive multi-signal transduction patterns. In conjunction with the handheld thermal reader device, a bimodal-type LFIA that combines size-regulation- and shape-engineering-mediated colorimetric-photothermal dual-response assay (coined as the SSCPD assay) with a limit of detection of 0.012 ng mL-1 for ractopamine (RAC) monitoring is achieved by integrating Au-MnOx with the competitive-type immunoreaction. This work illustrates the effectiveness of this strategy for establishing high-performance sensing, and the SSCPD assay may be extended to a wide spectrum of future point-of-care (POC) diagnostic applications.


Subject(s)
Metal Nanoparticles , Nanoparticles , Gold , Immunoassay , Antibodies , Colorimetry , Limit of Detection
18.
Atherosclerosis ; 377: 24-33, 2023 07.
Article in English | MEDLINE | ID: mdl-37379795

ABSTRACT

BACKGROUND AND AIMS: Atherosclerosis preferentially occurs at regions in arterial branching, curvature, and stenosis, which may be explained by the geometric predilection of low-density lipoprotein (LDL) concentration polarization that has been investigated in major arteries in previous studies. Whether this also happens in arterioles remains unknown. METHODS: Herein, a radially non-uniform distribution of LDL particles and a heterogeneous endothelial glycocalyx layer in the mouse ear arterioles, as shown by fluorescein isothiocyanate labeled wheat germ agglutinin (WGA-FITC), were successfully observed by a non-invasive two-photon laser-scanning microscopy (TPLSM) technique. The stagnant film theory was applied as the fitting function to evaluate LDL concentration polarization in arterioles. RESULTS: The concentration polarization rate (CPR, the ratio of the number of polarized cases to that of total cases) in the inner walls of curved and branched arterioles was 22% and 31% higher than the outer counterparts, respectively. Results from the binary logistic regression and multiple linear regression analysis showed that endothelial glycocalyx thickness increases CPR and the thickness of the concentration polarization layer (CPL). Flow field computation indicates no obvious disturbances or vortex in modeled arterioles with different geometries and the mean wall shear stress is about 7.7-9.0 Pa. CONCLUSIONS: These findings suggest a geometric predilection of LDL concentration polarization in arterioles for the first time, and the existence of an endothelial glycocalyx, acting together with a relatively high wall shear stress in arterioles, may explain to some extent why atherosclerosis rarely occurs in these regions.


Subject(s)
Atherosclerosis , Lipoproteins, LDL , Animals , Mice , Arterioles , Glycocalyx , Arteries
19.
J Acoust Soc Am ; 153(6): 3334, 2023 Jun 01.
Article in English | MEDLINE | ID: mdl-37328947

ABSTRACT

Sound waves can be used to carry out underwater activities. Rapidly and accurately simulating sound propagation is the basis for underwater detection. The wide-angle parabolic model has a good computational speed and accuracy and is currently the main numerical model for mid- and low-frequency sound propagation. The classical wide-angle parabolic equation model is discretized by the finite difference method and a low-order difference scheme is generally adopted. In this paper, a wide-angle parabolic equation model based on a spectral method is proposed. The depth operators of each layer are discretized via the Chebyshev spectral method and then assembled into a global matrix for the forward step. Lateral inhomogeneity is addressed by updating the global depth matrix while stepping forward. In the proposed spectral algorithm, both soft and hard seabeds can be accurately simulated by imposing boundary conditions, and the perfectly matched layer technique is used to truncate the unbounded acoustic half-space. Several representative numerical experiments prove the accuracy and efficiency of the proposed algorithm. However, the spectral method requires that the thickness of the layers does not change during the forward step. Thus, the current spectral algorithm cannot simulate waveguides with terrain undulation, which is its main limitation.


Subject(s)
Acoustics , Models, Theoretical , Sound , Oceans and Seas , Algorithms
20.
ACS Appl Mater Interfaces ; 15(23): 28267-28276, 2023 Jun 14.
Article in English | MEDLINE | ID: mdl-37264530

ABSTRACT

The semimetal-based photodetector possesses the intrinsic advantage of high response speed, low power consumption, and wide-range photoresponse. Here, we report the synthesis and application of 1 inch wafer-scale polycrystalline few layer 1T'-MoTe2 on the SiO2/Si substrate by employing a modified chemical vapor deposition method of predeposition of precursors. A continuous film with seamlessly stitched micrometer scale grains has been realized, and the pure 1T' phase was confirmed by Raman spectroscopy. An asymmetric metal electrode photodetector device of Pd-MoTe2-Au was designed and fabricated by using shadow mask-assisted UHV deposition. By measuring the self-powered photocurrent under the illumination of Xe lamp, we show that the device is sensitive to a wide spectra range (λ = 320-1200 nm) while maintaining high performance of the ON/OFF ratio (∼103), responsivity (1.2 A/W), and specific detectivity (7.68 × 1012 Jones). Under 450, 648, and 850 nm pulsed laser illumination, the response time achieves tens of microsecond scale. The device shows polarized photoresponse as well. Our work may promote the potential application of a self-powered high-performance photodetector based on 1T'-MoTe2.

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