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1.
Nature ; 2024 Jul 10.
Artículo en Inglés | MEDLINE | ID: mdl-38987599

RESUMEN

Tumours can obtain nutrients and oxygen required to progress and metastasize through the blood supply1. Inducing angiogenesis involves the sprouting of established vessel beds and their maturation into an organized network2,3. Here we generate a comprehensive atlas of tumour vasculature at single-cell resolution, encompassing approximately 200,000 cells from 372 donors representing 31 cancer types. Trajectory inference suggested that tumour angiogenesis was initiated from venous endothelial cells and extended towards arterial endothelial cells. As neovascularization elongates (through angiogenic stages SI, SII and SIII), APLN+ tip cells at the SI stage (APLN+ TipSI) advanced to TipSIII cells with increased Notch signalling. Meanwhile, stalk cells, following tip cells, transitioned from high chemokine expression to elevated TEK (also known as Tie2) expression. Moreover, APLN+ TipSI cells not only were associated with disease progression and poor prognosis but also hold promise for predicting response to anti-VEGF therapy. Lymphatic endothelial cells demonstrated two distinct differentiation lineages: one responsible for lymphangiogenesis and the other involved in antigen presentation. In pericytes, endoplasmic reticulum stress was associated with the proangiogenic BASP1+ matrix-producing pericytes. Furthermore, intercellular communication analysis showed that neovascular endothelial cells could shape an immunosuppressive microenvironment conducive to angiogenesis. This study depicts the complexity of tumour vasculature and has potential clinical significance for anti-angiogenic therapy.

2.
Mol Biotechnol ; 2024 May 28.
Artículo en Inglés | MEDLINE | ID: mdl-38806990

RESUMEN

Bladder cancer is a prevalent malignancy with high mortality rates worldwide. Hypoxia is a critical factor in the development and progression of cancers. However, whether and how hypoxia-related genes (HRGs) could affect the development and the chemotherapy response of bladder cancer is still largely unexplored. This study comprehensively explored the complex molecular landscape associated with hypoxia in bladder cancer by analyzing 260 hypoxia genes based on transcriptomic and genomic data in 411 samples. Employing the 109 dysregulated hypoxia genes for consensus clustering, we delineated two distinct bladder cancer clusters characterized by disparate survival outcomes and distinct oncogenic roles. We defined a HPscore that was correlated with a variety of clinical features, including TNM stages and pathologic grades. Tumor immune landscape analysis identified three immune clusters and close interactions between hypoxia genes and the various immune cells. Utilizing a network-based method, we defined 129 HRGs exerting influence on apoptotic processes and critical signaling pathways in cancer. Further analysis of chemotherapy drug sensitivity identified potential drug-target HRGs. We developed a Risk Score model that was related to the overall survival of bladder cancer patients based on doxorubicin-target HRGs: ACTG2, MYC, PDGFRB, DHRS2, and KLRD1. This study not only enhanced our understanding of bladder cancer at the molecular level but also provided promising avenues for the development of targeted therapies, representing a significant step toward the identification of effective treatments and addressing the urgent need for advancements in bladder cancer management.

3.
Small ; : e2311738, 2024 Mar 13.
Artículo en Inglés | MEDLINE | ID: mdl-38477695

RESUMEN

Metal silicide/Si photoelectrodes have demonstrated significant potential for application in photoelectrochemical (PEC) water splitting to produce H2 . To achieve an efficient and economical hydrogen evolution reaction (HER), a paramount consideration lies in attaining exceptional catalytic activity on the metal silicide surface with minimal use of noble metals. Here, this study presents the design and construction of a novel Ni0.95 Pt0.05 Si/p-Si photocathode. Dopant segregation is used to achieve a Schottky barrier height as high as 1.0 eV and a high photovoltage of 420 mV. To achieve superior electrocatalytic activity for HER, a dissolution-induced surface reconstruction (SR) strategy is proposed to in situ convert surface Ni0.95 Pt0.05 Si to highly active Pt2 Si. The resulting SR Ni0.95 Pt0.05 Si/p-Si photocathode exhibits excellent HER performance with an onset potential of 0.45 V (vs RHE) and a high maximum photocurrent density of 40.5 mA cm-2 and a remarkable applied bias photon-to-current efficiency (ABPE) of 5.3% under simulated AM 1.5 (100 mW cm-2 ) illumination. The anti-corrosion silicide layer effectively protects Si, ensuring excellent stability of the SR Ni0.95 Pt0.05 Si/p-Si photoelectrode. This study highlights the potential for achieving efficient PEC HER using bimetallic silicide/Si photocathodes with reduced Pt consumption, offering an auspicious perspective for the cost-effective conversion of solar energy to chemical energy.

4.
Talanta ; 271: 125716, 2024 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-38301373

RESUMEN

Mitochondrial copper signaling pathway plays a role in Alzheimer's disease (AD), especially in relevant Amyloid-ß oligomers (AßOs) neurotoxicity and mitochondrial dysfunction. Clarifying the relationship between mitochondrial copper homeostasis and both of mitochondrial dysfunction and AßOs neurotoxicity is important for understanding AD pathogenesis. Herein, we designed and synthesized a ratiometric fluorescent probe CHC-NS4 for Cu(I). CHC-NS4 possesses excellent ratiometric response, high selectivity to Cu(I) and specific ability to target mitochondria. Under mitochondrial dysfunction induced by oligomycin, mitochondrial Cu(I) levels gradually increased, which may be related to inhibition of ATP7A-mediated Cu(I) exportation and/or high expression of COX. On this basis, CHC-NS4 was further utilized to visualize the fluctuations of mitochondrial Cu(I) levels during progression of AD model cells induced by AßOs. It was found that mitochondrial Cu(I) levels were gradually elevated during the AD progression, which depended on not only AßOs concentration but also incubation time. Moreover, endocytosis maybe served as a prime pathway mode for mitochondrial Cu(I) dyshomeostasis induced by AßOs during AD progression. These results have provided a novel inspiration into mitochondrial copper biology in AD pathogenesis.


Asunto(s)
Enfermedad de Alzheimer , Enfermedades Mitocondriales , Humanos , Enfermedad de Alzheimer/metabolismo , Cobre/metabolismo , Péptidos beta-Amiloides/metabolismo , Colorantes Fluorescentes/metabolismo , Mitocondrias/metabolismo , Enfermedades Mitocondriales/metabolismo
5.
Chemistry ; 30(14): e202303552, 2024 Mar 07.
Artículo en Inglés | MEDLINE | ID: mdl-38158581

RESUMEN

CO2 is a greenhouse gas that contributes to environmental deterioration; however, it can also be utilized as an abundant C1 resource for the production of valuable chemicals. Solar-driven photoelectrocatalytic (PEC) CO2 utilization represents an advanced technology for the resourcing of CO2 . The key to achieving PEC CO2 utilization lies in high-performance semiconductor photoelectrodes. Si-based photoelectrodes have attracted increasing attention in the field of PEC CO2 utilization due to their suitable band gap (1.1 eV), high carrier mobility, low cost, and abundance on Earth. There are two pathways to PEC CO2 utilization using Si-based photoelectrodes: direct reduction of CO2 into small molecule fuels and chemicals, and fixation of CO2 with organic substrates to generate high-value chemicals. The efficiency and product selectivity of PEC CO2 utilization depends on the structures of the photoelectrodes as well as the composition, morphology, and size of the catalysts. In recent years, significant and influential progress has been made in utilizing Si-based photoelectrodes for PEC CO2 utilization. This review summarizes the latest research achievements in Si-based PEC CO2 utilization, with a particular emphasis on the mechanistic understanding of CO2 reduction and fixation, which will inspire future developments in this field.

6.
Front Genet ; 14: 1258862, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37900187

RESUMEN

Triple-negative breast cancer (TNBC) is a clinically aggressive subtype of breast cancer. Core transcriptional regulatory circuitry (CRC) consists of autoregulated transcription factors (TFs) and their enhancers, which dominate gene expression programs and control cell fate. However, there is limited knowledge of CRC in TNBC. Herein, we systemically characterized the activated super-enhancers (SEs) and interrogated 14 CRCs in breast cancer. We found that CRCs could be broadly involved in DNA conformation change, metabolism process, and signaling response affecting the gene expression reprogramming. Furthermore, these CRC TFs are capable of coordinating with partner TFs bridging the enhancer-promoter loops. Notably, the CRC TF and partner pairs show remarkable specificity for molecular subtypes of breast cancer, especially in TNBC. USF1, SOX4, and MYBL2 were identified as the TNBC-specific CRC TFs. We further demonstrated that USF1 was a TNBC immunophenotype-related TF. Our findings that the rewiring of enhancer-driven CRCs was related to cancer immune and mortality, will facilitate the development of epigenetic anti-cancer treatment strategies.

7.
Chempluschem ; 88(8): e202300285, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37485790

RESUMEN

Hydrogen evolution reaction (HER) coupled with biomass conversion is a sustainable route to produce clean energy H2 and value-added chemicals simultaneously. Herein, an amorphous Ni-Mo-B-O bifunctional electrocatalyst was synthesized through a facile electrodeposition method and employed as a cathode for HER to produce H2 and as an anode for the conversion of hydroxymethylfurfural (HMF) to furandicarboxylic acid (FDCA). Besides leading to the formation of amorphous structures, the introduction of Mo and B can increase the electron density and optimize the electronic structure of the electrocatalyst, thus substantially increasing the catalytic activity of the catalyst. After continuous reaction at a constant potential of 0.58 V vs. Hg/HgO for 8 hours, the conversion of HMF reached 98.86 %, and the selectivity of the target product FDCA was as high as 92.97 %. Finally, a two-electrolyzer system was constructed using the amorphous Ni-Mo-B-O as both cathode and anode to achieve simultaneous H2 production in the cathode chamber and FDCA production in the anode chamber at a low voltage. This work presents a promising strategy for the design and synthesis of high-performance non-noble metal electrocatalysts for efficient and cost-effective H2 production.

8.
J Invest Dermatol ; 143(11): 2283-2294.e17, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37201777

RESUMEN

Infiltrative basal cell carcinoma (iBCC) is a particularly aggressive subtype of basal cell carcinoma that tends to progress and recur after surgery, and its malignancy is closely related to the tumor microenvironment. In this study, we performed a comprehensive single-cell RNA analysis to profile 29,334 cells from iBCC and adjacent normal skin. We found active immune collaborations enriched in iBCC. Specifically, SPP1+CXCL9/10high macrophage 1 had strong BAFF signaling with plasma cells, and T follicular helper-like cells highly expressed the B-cell chemokine CXCL13. Heterogeneous proinflammatory SPP1+CXCL9/10high macrophage 1 and angiogenesis-related SPP1+CCL2high macrophage 1 were identified within the tumor microenvironment. Interestingly, we found an upregulation of major histocompatibility complex I molecules in fibroblasts in iBCC compared with those in adjacent normal skin. Moreover, MDK signals derived from malignant basal cells were markedly increased, and their expression was an independent factor in predicting the infiltration depth of iBCC, emphasizing its role in driving malignancy and remodeling the tumor microenvironment. In addition, we identified differentiation-associated SOSTDC1+IGFBP5+CTSV+ malignant basal subtype 1 and epithelial-mesenchymal transition-associated TNC+SFRP1+CHGA+ malignant basal subtype 2 cells. The high expression of malignant basal 2 cell markers was associated with the invasion and recurrence of iBCC. Altogether, our study helps to elucidate the cellular heterogeneity in iBCC and provides potential therapeutic targets for clinical research.

9.
Front Pediatr ; 11: 1157272, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37252040

RESUMEN

Objective: Central precocious puberty (CPP) is a rare condition that causes early sexual development in children. Although the cure is effective, the etiology of central precocious puberty is unclear. Methods: In total, 10 girls with central precocious puberty and same number of age-matched female controls were enrolled. Plasma samples were collected from each participant and subjected to untargeted metabolomics and lipidomics. Student's t-tests were employed to compare the mean of each metabolite and lipid. Furthermore, orthogonal partial least-squares discriminant analysis was conducted and the variable importance in the projection was calculated to identify differentially expressed metabolites or lipids. Subsequent bioinformatics was conducted to investigate the potential function of differentially expressed metabolites and lipids. Results: Fifty-nine differentially expressed metabolites were identified based on the criteria used (variable importance in the projection >1 and a P value < 0.05). Kyoto Encyclopedia Genes and Genome (KEGG) enrichment analysis showed that differentially expressed metabolites were enriched in four pathways: beta-alanine metabolism, histidine metabolism, bile secretion, and steroid hormone biosynthesis. As for the lipidomics, 41 differentially expressed lipids were observed and chain length analysis and lipid saturation analysis yielded similar results. Significant differences between the two groups were only observed in (O-acyl) ω-hydroxy fatty acids (OAHFA). Conclusion: The present study showed that antibiotic overuse, increased meat consumption, and obesity may have potential roles in the development of central precocious puberty in girls. Several metabolites have diagnostic value but further research is required.

10.
Anal Chem ; 95(17): 6915-6922, 2023 05 02.
Artículo en Inglés | MEDLINE | ID: mdl-37079771

RESUMEN

DNA-templated silver nanoclusters (DNA-AgNCs) have attracted significant attention due to their unique fluorescence properties. However, so far, the relatively low quantum yields of the DNA-AgNCs and the complex design of DNA-AgNC-based sensors have limited their application in biosensing or bioimaging. Herein, we report a novel fluorescence enhancement method. The ß-Amyloid Oligomer (AßO) aptamer (AptAßO) with A10/T10 at its 3' end can be directly used as the template to fabricate the AgNCs. When the AgNCs were hybridized with the complementary strand that has 12 bases suspended at its 3' terminal, being the same or complementary to the A/T at the 3' end of the AptAßO, and two-base mismatches in the complementary region of the aptamer excluded A10/T10, a dramatic fluorescence enhancement (maximum: ∼500-fold; maximum quantum yield: 31.5%) can be realized. The fluorescence enhancement should result from the aggregation-induced emission of the AgNCs, which can be attributed to forming the reticular structure of the hybridized product. To some extent, the method developed in this work is extendable. The fluorescence enhancement was also realized from the thrombin aptamer-templated AgNCs through designing the aptamer and the corresponding complementary strand according to the method. Based on the fluorescence enhancement of the AptAßO-templated AgNCs, an "on-off" fluorescence sensor was constructed for the sensitive and selective detection of AßO. This work provides a rational strategy to realize fluorescence enhancement for the aptamer-templated AgNCs and design an aptamer-based fluorescence sensor.


Asunto(s)
Técnicas Biosensibles , Nanopartículas del Metal , Plata/química , Fluorescencia , Nanopartículas del Metal/química , ADN/química , Proteínas Amiloidogénicas , Replicación del ADN , Espectrometría de Fluorescencia/métodos , Técnicas Biosensibles/métodos
11.
Chem Commun (Camb) ; 59(30): 4483-4486, 2023 Apr 11.
Artículo en Inglés | MEDLINE | ID: mdl-36967657

RESUMEN

A silicon nanowire-based fluorescence lifetime thermometer (NWFLT) was fabricated for the simultaneous measurement of intra- and extra-cellular temperatures. Using the NWFLT, an obvious heterogeneity of the temperature was found along the longitude direction of the NWFLT, especially between the inside and outside of the cell.

12.
Theranostics ; 12(17): 7532-7549, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36438481

RESUMEN

Rationale: The recurrence of cutaneous squamous cell carcinoma (cSCC) after surgery is associated with the reprogramming of the tumor microenvironment (TME), and remains a key factor affecting its outcomes. Methods: We employed single-cell RNA sequencing (scRNA-seq) to examine the dynamic changes in epithelial cells, T cells, myeloid cells, and fibroblasts between primary and recurrent cSCC. Cell clustering, cell trajectory, cell-cell communication, and gene set enrichment analysis were used to investigate the TME heterogeneity between primary and recurrent cSCC. Gene expression differences were monitored by IHC staining. Results: We examined the immunosuppressed microenvironment in recurrent cSCC, which exhibited a T cell-excluded and SPP1+ tumor-associated macrophages (TAMs)-enriched status. In recurrent cSCC, CD8+ T cells showed high exhaustion and low inflammatory features, while SPP1+ TAMs displayed global pro-tumor characteristics, including decreased phagocytosis and inflammation and increased angiogenesis. Furthermore, the subgroups of SPP1+ TAMs harbored distinct functions. SPP1+ CD209high TAMs showed features of phagocytosis, while SPP1+ CD209low TAMs tended to have a high angiogenic ability. A subpopulation of tumor-specific keratinocytes (TSKs) showed significant epithelial-mesenchymal transition (EMT) features in recurrent cSCC, probably due to their active communication with IL7R + cancer-associated fibroblasts (CAFs). Moreover, we found that the pleiotropic growth factor/cytokine Midkine (MDK) could provoke different cell-cell interactions in cSCC with distinctive staging. In primary cSCC, MDK was highly expressed in fibroblasts and could promote their proliferation and block the migration of tumor cells, while in recurrent cSCC, the high expression of MDK in TSKs promoted their proliferation and metastasis. Conclusion: Our study provides insights into the critical mechanisms of cSCC progression, which might facilitate the development of a powerful approach for the prevention and treatment of cSCC recurrence.


Asunto(s)
Carcinoma de Células Escamosas , Neoplasias Cutáneas , Humanos , Transición Epitelial-Mesenquimal , Linfocitos T CD8-positivos , Terapia de Inmunosupresión , Inflamación , Microambiente Tumoral
13.
Anal Chem ; 94(34): 11813-11820, 2022 08 30.
Artículo en Inglés | MEDLINE | ID: mdl-35925790

RESUMEN

Simultaneous monitoring of the ATP levels at various sites of a single cell is crucial for revealing the ATP-related processes and diseases. In this work, we rationally fabricated single nanowire-based fluorescence biosensors, by which the ATP levels of the cytoplasm and nucleus in a single cell can be simultaneously monitored with a high spatial resolution. Utilizing the as-fabricated single nanowire biosensor, we demonstrated that the ATP levels of the cytoplasm were around 20-30% lower than that of the nucleus in both L929 and HeLa cells. Observing the ATP fluctuation of the cytoplasm and nucleus of the L929 and HeLa cells stimulated by Ca2+, oligomycin, or under cisplatin-induced apoptosis, we found that the ATP levels at two cellular sites exhibited discriminative changes, revealing the different mechanisms of the ATP at these two cellular sites in response to the stimulations.


Asunto(s)
Técnicas Biosensibles , Nanocables , Adenosina Trifosfato , Citoplasma , Células HeLa , Humanos
14.
Nano Lett ; 22(4): 1541-1548, 2022 Feb 23.
Artículo en Inglés | MEDLINE | ID: mdl-35118860

RESUMEN

Optical regulation strategy with the aid of hybrid materials can significantly optimize the performance of terahertz devices. Gold nanobipyramids (AuNBPs) with synthetical tunability to the near-infrared band show strong local field enhancement, which improves optical coupling at the interface and benefits the modulation performance. We design AuNBPs-integrated terahertz modulators with multiple structured surfaces and demonstrate that introducing AuNBPs can effectively enhance their modulation depths. In particular, an ultrahigh modulation enhancement of 1 order of magnitude can be achieved in the AuNBPs hybrid metamaterials accompanied by the multifunctional modulation characteristics. By application of the coupled Lorentz oscillator model, the theoretical calculation suggests that the optical regulation with AuNBPs originates from increased damping rate and higher coupling coefficient under pump excitation. Additionally, a terahertz spatial light modulator is constructed to demonstrate multiple imaging display and consume extremely low power, which is promising for the potential application in spatial and frequency selective imaging.

15.
Anal Chem ; 93(45): 15072-15079, 2021 11 16.
Artículo en Inglés | MEDLINE | ID: mdl-34617743

RESUMEN

Detecting the temperature of intracellular mitochondria with high sensitivity and stability is crucial to understanding the cellular metabolism and revealing the processes of mitochondria-related physiology. In this paper, employing the long fluorescence lifetime of modified Au nanoclusters (mAuNCs) by 4-(carboxybutyl) triphenylphosphonium bromide, we developed a fluorescence lifetime thermometer with high sensitivity and stability for the temperature of the intracellular mitochondria. A high relative temperature sensitivity of 2.8% and excellent photostability were achieved from the present thermometer. After incubation with L929 cells, the mAuNCs could be endocytosed into the cells and targeted the mitochondria, and the temperature changes at the L929 cells' mitochondria, which were stimulated by carbonyl cyanide 3-chlorophenylhydrazone and Ca2+, were successfully detected via the fluorescence lifetime images of the mAuNCs. Furthermore, utilizing the mAuNCs, we clarified the effect of Mg2+ on the temperature of the intracellular mitochondria. The strategy of employing a material with a long fluorescence lifetime and remarkable stability to fabricate the fluorescence lifetime thermometer for mitochondria can be used to design various thermometers for other organelles.


Asunto(s)
Mitocondrias , Termómetros , Células HeLa , Humanos , Espectrometría de Fluorescencia , Temperatura
16.
Biosens Bioelectron ; 178: 113025, 2021 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-33529860

RESUMEN

The aptasensor, developed from the aptamer, has aroused wide concern in recent years owing to its high sensitivity and specificity. However, the quenching unit involved in the most of the aptasensors is indispensable to the fabrication of an aptasensor, which would undoubtedly increase the complexity of the device. In this study, a facile strategy was developed for construction of the quencher-free aptasensors, in which the quenching units can be omitted, and only an aptamer strand and a fluorophore are necessary. Distinguishable from the configuration of the traditional ones, the aptasensors developed in this work rationally employed the intrinsic quenching abilities of the analytes to directly regulate the fluorescence of the fluorophore. Furthermore, the aptamer strand as a discriminatory unit efficiently captured the corresponding analytes to around the fluorophores. As a result, the fluorescence of the aptasensor can be significantly sensitive to the analytes. The generality of the current design is evidenced by the successful fabrication of seven quencher-free aptasensors for Cu2+, Ag+, Hg2+, ATP and dopamine through 6-FAM labeling aptamers of Cu2+, Ag+, Hg2+, ATP, dopamine, 5-TAMRA and ROX labeling aptamers of Cu2+. Present strategy endows an aptasensor with a simple structure, high selectivity and fine sensitivity. The configuration of the quencher-free aptasensors fabricated in this work can be readily utilized for more aptasensors.


Asunto(s)
Aptámeros de Nucleótidos , Técnicas Biosensibles , Mercurio , Dopamina , Colorantes Fluorescentes
17.
Arch Med Sci ; 17(1): 135-141, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33488866

RESUMEN

INTRODUCTION: The DEK gene encodes a nuclear phosphoprotein which is involved in multiple cell metabolic processes, such as DNA damage repair, mRNA splicing, modifying chromatin structure and transcription regulation. DEK has been shown to be overexpressed in various solid human tumors and associated with patient prognosis. In this study, our aim was to investigate DEK protein expression and its relationship with clinicopathological parameters and prognosis in esophageal squamous cell carcinoma (ESCC). MATERIAL AND METHODS: Tissue samples were collected from 120 routinely diagnosed ESCC patients who underwent surgical resection at the Zhongshan Hospital, Xiamen University in the period from June 2011 to May 2013. The expression of DEK was determined by immunohistochemistry. RESULTS: DEK protein was ubiquitously distributed in the nucleus of ESCC cells, and its positive rate (71.7%) was significantly higher in cancer samples than those of para-carcinoma (21.4%) or normal esophageal (13.9%) tissues (p < 0.001). Similarly, significantly more cells overexpressing DEK were found in ESCC tissues (57.5%) in comparison with para-carcinoma samples (11.4%) and normal esophageal mucosa (0%, p < 0.001). The DEK overexpression rate was significantly different between patients with different tumor-node-metastasis (TNM) stages and differentiation degrees (p < 0.001). ESCC cases with elevated DEK amounts showed reduced disease-free and 5-year survival rates compared with those expressing low DEK amounts (p < 0.001). DEK overexpression was also confirmed to independently predict prognosis in ESCC (HR = 4.121, 95% CI: 1.803-9.42, p = 0.001). CONCLUSIONS: DEK expression is positively correlated with reduced survival in ESCC patients. DEK has potential to be an independent biomarker in predicting prognosis of ESCC patients.

18.
ACS Appl Mater Interfaces ; 12(41): 45807-45813, 2020 Oct 14.
Artículo en Inglés | MEDLINE | ID: mdl-32951417

RESUMEN

Current strategies to construct cell-based bioartificial tissues largely remain on a multicell level. Taking cell diversity into account, single-cell manipulation is urgently needed for delicate bioartificial tissue construction. Current single-cell isolation and profiling techniques involve invasive processes and thus are not applicable for single-cell manipulation. Here, we managed to fabricate peptide-liquid metal hybrid hydrogels as "cell ambers" which were suitable for single-cell isolation as well as further handling. The successful preparation of uniform liquid metal nanoparticles allowed the fabrication of peptide-liquid metal hydrogel with excellent recovery property upon mechanical destruction. The alkaline phosphatase-instructed supramolecular self-assembly process allowed the formation of microhydrogel post-filling in the PDMS template. The co-culture of the hydrogel precursor and mammalian cells realized the embedding of cells into elastic hydrogels which were the so-called cell ambers. The cell ambers turned out to be biocompatible and capable of supporting cell survival. Aided with the micro-operating system and a laser scanning confocal microscope, we could arrange these as-prepared 3D single-cell ambers into various patterns as desired. Our strategy provided the possibility to manipulate a single cell, which served as a prototype of cell architecture toward cell-based bioartificial tissue construction.


Asunto(s)
Fosfatasa Alcalina/metabolismo , Dimetilpolisiloxanos/metabolismo , Hidrogeles/metabolismo , Péptidos/metabolismo , Análisis de la Célula Individual , Células Cultivadas , Dimetilpolisiloxanos/síntesis química , Dimetilpolisiloxanos/química , Humanos , Hidrogeles/síntesis química , Hidrogeles/química , Estructura Molecular , Tamaño de la Partícula , Péptidos/química , Propiedades de Superficie
19.
ACS Appl Mater Interfaces ; 12(35): 39092-39097, 2020 Sep 02.
Artículo en Inglés | MEDLINE | ID: mdl-32805824

RESUMEN

Silicon (Si)-based Schottky junction photoelectrodes have attracted considerable attention for photoelectrochemical (PEC) water splitting in recent years. To realize highly efficient Si-based Schottky junction photoelectrodes, the critical challenge is to enable the photoelectrodes to not only have a high Schottky barrier height (SBH), by which a high photovoltage can be obtained, but also ensure an efficient charge transport. Here, we propose and demonstrate a strategy to fabricate a high-performance NiSi/n-Si Schottky junction photoanode by metal silicidation in conjunction with dopant segregation (DS). The metal silicidation produces photoanodes with a high-quality NiSi/Si interface without a disordered SiO2 layer, which ensures highly efficient charge transport, and thus a high saturated photocurrent density of 33 mA cm-2 was attained for the photoanode. The subsequent DS gives the photoanodes a high SBH of 0.94 eV through the introduction of electric dipoles at the NiSi/n-Si interface. As a result, a high photovoltage and favorable onset potential of 1.03 V vs RHE was achieved. In addition, the strong alkali corrosion resistance of NiSi also endows the photoanode with a high stability during PEC operation in 1 M KOH. Our work provides a universal strategy to fabricate metal-silicide/Si Schottky junction photoelectrodes for high-performance PEC water splitting.

20.
Nanotechnology ; 31(36): 365502, 2020 Sep 04.
Artículo en Inglés | MEDLINE | ID: mdl-32442993

RESUMEN

Intracellular thermometry with favorable biocompatibility and precision is essential for insight into temperature-related cellular events. Here, liquid-core nanocapsule ratiometric fluorescent thermometers (LCN-RFTs) were prepared by encapsulating thermosensitive organic fluorophores (N,N'-di(2-ethylhexyl)-3,4,9,10-perylene tetracarboxylic diimide, DEH-PDI) with hydrophobic solvent (2,2,4-trimethylpentane, TMP) into polystyrene/silica hybrid nanoshells. As the fluorescent thermosensitive unit of the LCN-RFT, the TMP solution of DEH-PDI was responsible for the fluorescence response to temperature. Benefitting from the hydrophilic nanoshells, the LCN-RFTs exhibited favorable anti-interference and biocompatibility. Furthermore, the LCN-RFTs showed an excellent precision of 0.02 °C-0.10 °C in a simulated physiological environment from 10.00 °C to 90.00 °C, and were employed to realize intracellular thermometry with an outstanding precision of 0.06 °C-0.14 °C. This work provides a feasible method of using hydrophobic organic fluorophores for intracellular thermometry by encapsulating them into nanocapsules.


Asunto(s)
Materiales Biocompatibles/química , Colorantes Fluorescentes/química , Imidas/química , Nanocápsulas/química , Perileno/análogos & derivados , Animales , Línea Celular , Ratones , Microscopía Confocal , Microscopía Electrónica de Transmisión , Perileno/química , Dióxido de Silicio/química , Espectroscopía Infrarroja por Transformada de Fourier , Temperatura , Termómetros
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