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1.
Adv Sci (Weinh) ; : e2401877, 2024 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-38639403

RESUMO

In recent decades, there has been a significant increase in the application of single-molecule electrical analysis platforms in studying proteins and peptides. These advanced analysis methods have the potential for deep investigation of enzymatic working mechanisms and accurate monitoring of dynamic changes in protein configurations, which are often challenging to achieve in ensemble measurements. In this work, the prominent research progress in peptide and protein-related studies are surveyed using electronic devices with single-molecule/single-event sensitivity, including single-molecule junctions, single-molecule field-effect transistors, and nanopores. In particular, the successful commercial application of nanopores in DNA sequencing has made it one of the most promising techniques in protein sequencing at the single-molecule level. From single peptides to protein complexes, the correlation between their electrical characteristics, structures, and biological functions is gradually being established. This enables to distinguish different molecular configurations of these biomacromolecules through real-time electrical monitoring of their life activities, significantly improving the understanding of the mechanisms underlying various life processes.

2.
Dig Dis Sci ; 2024 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-38662158

RESUMO

BACKGROUND: Long noncoding RNAs (lncRNAs) have been shown to be related to the occurrence and development of a variety of cancers including hepatocellular carcinoma (HCC). However, a large number of potential HCC-related lncRNAs remain undiscovered and are yet to be fully understood. METHODS: Differentially expressed lncRNAs were first obtained from the tumor tissues and adjacent normal tissues of five HCC patients using high-throughput microarray chips. Then the expression levels of 10 differentially expressed lncRNAs were verified in 50 pairs of tissue samples from patients with HCC by quantitative real-time PCR (qRT-PCR). The oncogenic effects of lncRNA-4045 (ENST00000524045.6) in HCC cell lines were verified through a series of in vitro experiments including CCK-8 assay, plate clone formation assay, transwell assay, scratch assay, and flow cytometry. Subsequently, the potential target genes of lncRNA-4045 were predicted by bioinformatics analysis, fluorescence in situ hybridization assay, and RNA sequencing. The mechanism of lncRNA-4045 in HCC was explored by WB assay as well as rescue and enhancement experiments. RESULTS: The results from microarray chips showed 1,708 lncRNAs to have been significantly upregulated and 2725 lncRNAs to have been significantly downregulated in HCC tissues. Via validation in 50 HCC patients, a novel lncRNA lncRNA-4045 was found significantly upregulated in HCC tissues. Additionally, a series of in vitro experiments showed that lncRNA-4045 promoted the proliferation, invasion, and migration of HCC cell lines, and inhibited the apoptosis of HCC cell lines. The results of qRT-PCR in HCC tissues showed that the expression levels of AKR1B10 were significantly positively correlated with lncRNA-4045. LncRNA-4045 knockdown significantly down-regulated AKR1B10 protein expression, and overexpression of lncRNA-4045 led to significant up-regulation of AKR1B10 protein in HCC cell lines. Lastly, down-regulation of AKR1B10 could partially eliminate the enhancement of cell proliferation induced by lncRNA-4045 overexpression, while up-regulation of AKR1B10 was shown to enhance those effects. CONCLUSION: LncRNA-4045 may promote HCC via enhancement of the expression of AKR1B10 protein.

3.
J Phys Chem Lett ; 15(12): 3267-3275, 2024 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-38489078

RESUMO

For sufficiently low biases, Ohm's law, the cornerstone of electricity, stating that current I and voltage V are proportional, is satisfied at low biases for all known systems ranging from macroscopic conductors to nanojunctions. In this study, we predict theoretically and demonstrate experimentally that in single-molecule junctions fabricated with single-layer graphene as electrodes the current at low V scales as the cube of V, thereby invalidating Ohm's law. The absence of the ohmic regime is a direct consequence of the unique band structure of the single-layer graphene, whose vanishing density of states at the Dirac points precludes electron transfer from and to the electrodes at low biases.

4.
Langmuir ; 40(13): 7242-7248, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38501957

RESUMO

The metal-thiol interface is ubiquitous in nanotechnology and surface chemistry. It is not only used to construct nanocomposites but also plays a decisive role in the properties of these materials. When organothiol molecules bind to the gold surface, there is still controversy over whether sulfhydryl groups can form disulfide bonds and whether these disulfide bonds can remain stable on the gold surface. Here, we investigate the intrinsic properties of sulfhydryl groups on the gold surface at the single-molecule level using a scanning tunneling microscope break junction technique. Our findings indicate that sulfhydryl groups can react with each other to form disulfide bonds on the gold surface, and the electric field can promote the sulfhydryl coupling reaction. In addition to these findings, ultraviolet irradiation is used to effectively regulate the coupling between sulfhydryl groups, leading to the formation and cleavage of disulfide bonds. These results unveil the intrinsic properties of sulfhydryl groups on the gold surface, therefore facilitating the accurate construction of broad nanocomposites with the desired functionalities.

5.
Nat Nanotechnol ; 2024 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-38448520

RESUMO

Free radicals, generally formed through the cleavage of covalent electron-pair bonds, play an important role in diverse fields ranging from synthetic chemistry to spintronics and nonlinear optics. However, the characterization and regulation of the radical state at a single-molecule level face formidable challenges. Here we present the detection and sophisticated tuning of the open-shell character of individual diradicals with a donor-acceptor structure via a sensitive single-molecule electrical approach. The radical is sandwiched between nanogapped graphene electrodes via covalent amide bonds to construct stable graphene-molecule-graphene single-molecule junctions. We measure the electrical conductance as a function of temperature and track the evolution of the closed-shell and open-shell electronic structures in real time, the open-shell triplet state being stabilized with increasing temperature. Furthermore, we tune the spin states by external stimuli, such as electrical and magnetic fields, and extract thermodynamic and kinetic parameters of the transition between closed-shell and open-shell states. Our findings provide insights into the evolution of single-molecule radicals under external stimuli, which may proof instrumental for the development of functional quantum spin-based molecular devices.

6.
World J Gastrointest Oncol ; 16(2): 475-492, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38425404

RESUMO

BACKGROUND: B56ε is a regulatory subunit of the serine/threonine protein phosphatase 2A, which is abnormally expressed in tumors and regulates various tumor cell functions. At present, the application of B56ε in pan-cancer lacks a comprehensive analysis, and its role and mechanism in hepatocellular carcinoma (HCC) are still unclear. AIM: To analyze B56ε in pan-cancer, and explore its role and mechanism in HCC. METHODS: The Cancer Genome Atlas, Genotype-Tissue Expression, Gene Expression Profiling Interactive Analysis, and Tumor Immune Estimation Resource databases were used to analyze B56ε expression, prognostic mutations, somatic copy number alterations, and tumor immune characteristics in 33 tumors. The relationships between B56ε expression levels and drug sensitivity, immunotherapy, immune checkpoints, and human leukocyte antigen (HLA)-related genes were further analyzed. Gene Set Enrichment Analysis (GSEA) was performed to reveal the role of B56ε in HCC. The Cell Counting Kit-8, plate cloning, wound healing, and transwell assays were conducted to assess the effects of B56ε interference on the malignant behavior of HCC cells. RESULTS: In most tumors, B56ε expression was upregulated, and high B56ε expression was a risk factor for adrenocortical cancer, HCC, pancreatic adenocarcinoma, and pheochromocytoma and paraganglioma (all P < 0.05). B56ε expression levels were correlated with a variety of immune cells, such as T helper 17 cells, B cells, and macrophages. There was a positive correlation between B56ε expression levels with immune checkpoint genes and HLA-related genes (all P < 0.05). The expression of B56ε was negatively correlated with the sensitivity of most chemotherapy drugs, but a small number showed a positive correlation (all P < 0.05). GSEA analysis showed that B56ε expression was related to the cancer pathway, p53 downstream pathway, and interleukin-mediated signaling in HCC. Knockdown of B56ε expression in HCC cells inhibited the proliferation, migration, and invasion capacity of tumor cells. CONCLUSION: B56ε is associated with the microenvironment, immune evasion, and immune cell infiltration of multiple tumors. B56ε plays an important role in HCC progression, supporting it as a prognostic marker and potential therapeutic target for HCC.

7.
Int Immunopharmacol ; 130: 111740, 2024 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-38401464

RESUMO

BACKGROUND: As a homologous counterpart to the prokaryotic oligonuclease found in the cellular cytoplasm and mitochondrion, REXO2 assumes a pivotal role in the maintenance of mitochondrial homeostasis. Nevertheless, the precise functions and mechanisms by which REXO2 operates within the context of hepatocellular carcinoma (HCC) have hitherto remained unexamined. METHODS: The expression levels of REXO2 in HCC tissues were evaluated through the utilization of the immunohistochemical (IHC) method, and subsequently, the association between REXO2 expression and the clinicopathological characteristics of HCC patients was scrutinized employing the χ2 test. A battery of experimental assays, encompassing CCK8 viability assessment, cell colony formation, wound healing, and transwell assays, were conducted with the aim of elucidating the biological role of REXO2 within HCC cells. Complementary bioinformatics analyses were undertaken to discern potential correlations between REXO2 and immune infiltration in tumor tissues. RESULTS: Our IHC findings have unveiled a notable up-regulation of REXO2 within HCC tissues, and this heightened expression bears the status of an independent prognostic factor, portending an adverse outcome for HCC patients (P < 0.05). Upon the attenuation of REXO2 expression, a discernible reduction in the rates of proliferation, invasion and migration of HCC cells ensued (P < 0.05). Furthermore, transcriptome sequencing analysis has provided insights into the putative influence of REXO2 on the development of HCC through the modulation of TNF and NF-κB signaling pathways. Additionally, our bioinformatics analyses have demonstrated a positive correlation between REXO2 and tumor immune cell infiltration, as well as immune checkpoint CTLA-4. CONCLUSIONS: In summation, our results posit an association between the up-regulation of REXO2 and adverse prognostic outcomes, alongside the involvement of immune-related signaling pathways and tumor immune infiltration within the realm of HCC.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/genética , Regulação para Cima , Neoplasias Hepáticas/genética , Mitocôndrias , Bioensaio , Prognóstico
8.
Chem Rec ; 24(3): e202300361, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38362667

RESUMO

Smart textile fabrics have been widely investigated and used in flexible wearable electronics because of their unique structure, flexibility and breathability, which are highly desirable with integrated multifunctionality. Recent years have witnessed the rapid development of textile fiber-based flexible wearable devices. However, the pristine textile fibers still can't meet the high standards for practical flexible wearable devices, which calls for the development of some effective modification strategies. In this review, we summarize the recent advances in the flexible wearable devices based on the textile fibers, putting special emphasis on the design and modifications of textile fibers. In addition, the applications of textile fibers in various fields and the critical role of textile fibers are also systematically discussed, which include the supercapacitors, sensors, triboelectric nanogenerators, thermoelectrics, and other self-powered electronic devices. Finally, the main challenges that should be overcome and some effective solutions are also manifested, which will guide the future development of more effective textile fiber-based flexible wearable devices.

9.
Natl Sci Rev ; 11(3): nwae009, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38344115

RESUMO

Enhancing the thermoelectric transport properties of conductive polymer materials has been a long-term challenge, in spite of the success seen with molecular doping strategies. However, the strong coupling between the thermopower and the electrical conductivity limits thermoelectric performance. Here, we use polaron interfacial occupied entropy engineering to break through this intercoupling for a PEDOT:PSS (poly(3,4-ethylenedioxythiophene)-poly(4-styrenesulfonate)) thin film by using photochromic diarylethene (DAE) dopants coupled with UV-light modulation. With a 10-fold enhancement of the thermopower from 13.5 µV K-1 to 135.4 µV K-1 and almost unchanged electrical conductivity, the DAE-doped PEDOT:PSS thin film achieved an extremely high power factor of 521.28 µW m-1 K-2 from an original value of 6.78 µW m-1 K-2. The thermopower was positively correlated with the UV-light intensity but decreased with increasing temperature, indicating resonant coupling between the planar closed DAE molecule and PEDOT. Both the experiments and theoretical calculations consistently confirmed the formation of an interface state due to this resonant coupling. Interfacial entropy engineering of polarons could play a critical role in enhancing the thermoelectric performance of the organic film.

10.
Inorg Chem ; 63(8): 3769-3780, 2024 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-38346334

RESUMO

Lanthanide-based single-ion magnets have attracted much interest due to their great potential for information storage at the level of one molecule. Among various strategies to enhance magnetization blocking in such complexes, the synthesis of axially symmetric compounds is regarded as the most promising. Here, we investigate theoretically the magnetization blocking of several lanthanide ions (Tb3+, Dy3+, Ho3+, Er3+, and Tm3+) encapsulated in highly symmetric zigzag boron nitride nanotubes (BNNTs) of different diameters with ab initio methodology. We found that Tb3+@(7,0)BNNT, Dy3+@(7,0)BNNT, and Tm3+@(5,0)BNNT are suitable SIM candidates, while the other investigated complexes from this series show no signs of magnetization blocking owing to a hard competition between contributions to the crystal field of the lanthanide ion from neighboring and more distant atoms of the nanotube.

11.
J Org Chem ; 89(2): 1241-1248, 2024 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-38163764

RESUMO

Lewis acid-catalyzed cycloaddition between bicyclo[1.1.0]butanes (BCBs) and unsaturated substrates has recently been demonstrated to be a powerful strategy for synthesizing bicyclo[2.1.1]hexanes. However, their reaction mechanisms remain elusive. This computational work explored the recently developed TMSOTf-catalyzed cycloaddition of BCB ketone to ketene and determined the rate-determining step as the activation of BCB ketone. Contrary to the previous proposal of BCB enolate as the active species, this work instead identified the catalytically active species to be a partially Lewis acid-activated BCB cation, which shows a greater electrophilicity and larger orbital interactions with ketene compared to those of the pristine BCB. The most favorable reaction pathway uniquely utilizes this activated BCB species as an electrophile to react with ketene as a nucleophile, while the previously proposed enolate is relatively inactive. Moreover, the in situ-generated TfO anion is revealed to be non-innocent, and its coordination mode and orientation could affect the reaction kinetics.

12.
Nat Commun ; 14(1): 7695, 2023 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-38001141

RESUMO

The transformation from one compound to another involves the breaking and formation of chemical bonds at the single-bond level, especially during catalytic reactions that are of great significance in broad fields such as energy conversion, environmental science, life science and chemical synthesis. The study of the reaction process at the single-bond limit is the key to understanding the catalytic reaction mechanism and further rationally designing catalysts. Here, we develop a method to monitor the catalytic process from the perspective of the single-bond energy using high-resolution scanning tunneling microscopy single-molecule junctions. Experimental and theoretical studies consistently reveal that the attack of a halogen atom on an Au atom can reduce the breaking energy of Au-S bonds, thereby accelerating the bond cleavage reaction and shortening the plateau length during the single-molecule junction breaking. Furthermore, the distinction in catalytic activity between different halogen atoms can be compared as well. This study establishes the intrinsic relationship among the reaction activation energy, the chemical bond breaking energy and the single-molecule junction breaking process, strengthening our mastery of catalytic reactions towards precise chemistry.

13.
Front Immunol ; 14: 1260112, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37781374

RESUMO

Background: The clinical progression of individuals afflicted with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection exhibits significant heterogeneity, particularly affecting the elderly population to a greater extent. Consequently, the association between nutrition and microbiota has garnered considerable interest. Hence, the objective of this study was to gather clinical data pertaining to the influence of diverse nutritional support interventions on the prognosis of geriatric patients with COVID-19, while additionally examining the fecal microbiota of these individuals to assess the repercussions of microecological alterations on their prognostic outcomes. Results: A total of 71 elderly patients diagnosed with severe COVID-19 were included in this study. These patients were subsequently divided into two groups, namely the enteral nutrition (EN) group and the parenteral nutrition (PN) group, based on the type of nutritional support therapy they received after admission. The occurrence of complications was observed in 10.4% of patients in the EN group, whereas it was significantly higher at 69.6% in the PN group (P<0.001). Furthermore, the 60-day mortality rate was 2.1% (1/48) in the EN group, while it was notably higher at 30.4% (7/23) in the PN group (P=0.001). To identify the independent predictors of 60-day mortality, stepwise logistic regression analysis was employed. Among different bacterial groups, Enterococcus_faecium (18.19%) and Pseudomonas_aeruginosa (1.91%) had higher average relative abundance in the PN group (P<0.05). However, the relative abundance of Ruminococcus was higher in the EN group. Further Spearman correlation analysis showed that Enterococcus_faecium was positively correlated with poor clinical prognosis, while Ruminococcus was negatively correlated with poor clinical prognosis. Conclusions: This study shows that the changes in the composition of intestinal flora in elderly COVID-19 patients receiving different nutritional support strategies may be related to different clinical outcomes. The abundance of Enterococcus_faecium in elderly COVID-19 patients receiving PN is significantly increased and is closely related to poor clinical outcomes. It highlights the potential of microbiome-centric interventions to mitigate and manage COVID-19 in older adults with different nutritional support options.


Assuntos
COVID-19 , Microbioma Gastrointestinal , Humanos , Idoso , COVID-19/terapia , SARS-CoV-2 , Prognóstico , Nutrição Parenteral/métodos
14.
Front Biosci (Landmark Ed) ; 28(8): 162, 2023 08 11.
Artigo em Inglês | MEDLINE | ID: mdl-37664917

RESUMO

BACKGROUND: Myc-associated zinc finger protein (MAZ) plays a role in cancer progression and metastasis. However, the role and underlying molecular mechanism of MAZ in thyroid cancer have not yet been fully elucidated. This study aimed to explore the clinical significance of MAZ in thyroid cancer tissues, and clarify its mechanism in the occurrence and development of thyroid cancer. METHODS: The expression level of MAZ protein in thyroid cancer tissues was detected by bioinformatics analysis and immunohistochemistry (IHC). The relationship between the expression level of MAZ and clinicopathological characteristics of thyroid cancer patients was analyzed by multivariate logistic regression analysis. Quantitative reverse-transcription polymerase chain reaction (RT-qPCR) was used to detect the mRNA expression level of MAZ in thyroid cancer cell lines. After MAZ knockdown cell lines were constructed, wound healing and Transwell assays were used to detect the migratory and invasive abilities of cancer cells. RESULTS: The results of IHC showed that the expression level of MAZ protein in thyroid cancer tissues was higher than that in normal adjacent thyroid tissues (p < 0.05), which was consistent with the high expression level of MAZ in thyroid cancer tissues found in The Cancer Genome Atlas (TCGA) database. The results of multivariate logistic regression analysis indicated that the expression level of MAZ was correlated with tumor diameter and tumor capsule of thyroid cancer patients. Moreover, patients with the high MAZ expression level had shorter overall and disease-free survival compared with thyroid cancer patients with the low MAZ expression level (p < 0.05). Further cell function assays indicated that downregulation of MAZ expression level could inhibit the migration and invasion of thyroid cancer cell lines. Moreover, the expression level of epithelial-mesenchymal transition (EMT)-related factor fibronectin 1 (FN1) was obtained from the RNA-seq of MAZ knockdown in thyroid cancer cells. RT-qPCR confirmed that the expression level of FN1 was elevated in MAZ knockdown cell lines (p < 0.05). Bioinformatics analysis indicated that the expression level of FN1 was upregulated in thyroid cancer tissues and had a negative relationship with the expression level of MAZ, as evidenced by correlation analysis. CONCLUSIONS: A high expression level of MAZ in thyroid cancer tissues was associated with a poor prognosis of patients. MAZ could affect the progression of thyroid cancer by inducing the EMT process.


Assuntos
Neoplasias da Glândula Tireoide , Humanos , Câncer Papilífero da Tireoide/genética , Neoplasias da Glândula Tireoide/genética , Dedos de Zinco/genética
15.
BMC Mol Cell Biol ; 24(1): 28, 2023 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-37726647

RESUMO

Inflammation plays a crucial role in the progression of Subacute Ruminal Acidosis (SARA). The experiment was designed to investigate anti-inflammatory effects of glycyrrhizin on goats ruminal epithelial cells (GREC) which were induced SARA by Lipopolysaccharide (LPS) in vitro. The GREC were induced SARA by adding LPS at the concentration of 5 µm and glycyrrhizin was added at different concentration of 0, 60, 90, 120, 150 µm. The structural integrity of LPS-induced GREC with the treatment of glycyrrhizin were observed by electron microscope; The levels of inflammatory factors TNF-α, IL-1ß, IL-6, IL-8 and IL-12 were measured by ELISA; The number of Zo-1 and Occludin were measured, the expression of tight junction protein Occludin were measured by Western blot, and the mRNA expression of NF-κB, TNF-α, IL-1ß, IL-6, IL-8 and IL-12 were measured in vitro. The results showed that higher concentration treatment of glycyrrhizin led to better morphology in LPS-induced GREC. Glycyrrhizin inhibited the growth of inflammatory factors TNF-α, IL-1ß, IL-6, IL-8 and IL-12 in a dose-dependent manner. The number of ZO-1 and Occludin increased with the increase of adding of glycyrrhizin. Western blot analysis showed that the expression of tight junction protein Occludin in LPS-induced GREC increased with the adding of glycyrrhizin in a dose-dependent manner. Furthermore, the mRNA expression of NF-κB, TNF-α, IL-1ß, IL-6, IL-8 and IL-12 decreased significantly with the increase treatment of glycyrrhizin. Glycyrrhizin significantly inhibits LPS-induced inflammatory mediators in GREC and the effects are better with the increase treatment of glycyrrhizin in vitro.


Assuntos
Cabras , Lipopolissacarídeos , Animais , Lipopolissacarídeos/farmacologia , Ácido Glicirrízico/farmacologia , NF-kappa B , Interleucina-6 , Interleucina-8 , Ocludina , Fator de Necrose Tumoral alfa , Células Epiteliais , RNA Mensageiro
16.
Nanomicro Lett ; 15(1): 211, 2023 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-37698706

RESUMO

Chirality, as the symmetric breaking of molecules, plays an essential role in physical, chemical and especially biological processes, which highlights the accurate distinction among heterochiralities as well as the precise preparation for homochirality. To this end, the well-designed structure-specific recognizer and catalysis reactor are necessitated, respectively. However, each kind of target molecules requires a custom-made chiral partner and the dynamic disorder of spatial-orientation distribution of molecules at the ensemble level leads to an inefficient protocol. In this perspective article, we developed a universal strategy capable of realizing the chirality detection and control by the external symmetry breaking based on the alignment of the molecular frame to external stimuli. Specifically, in combination with the discussion about the relationship among the chirality (molecule), spin (electron) and polarization (photon), i.e., the three natural symmetry breaking, single-molecule junctions were proposed to achieve a single-molecule/event-resolved detection and synthesis. The fixation of the molecular orientation and the CMOS-compatibility provide an efficient interface to achieve the external input of symmetry breaking. This perspective is believed to offer more efficient applications in accurate chirality detection and precise asymmetric synthesis via the close collaboration of chemists, physicists, materials scientists, and engineers.

17.
Nat Commun ; 14(1): 5203, 2023 08 25.
Artigo em Inglês | MEDLINE | ID: mdl-37626077

RESUMO

Intrinsically disordered proteins (IDPs) play crucial roles in cellular processes and hold promise as drug targets. However, the dynamic nature of IDPs remains poorly understood. Here, we construct a single-molecule electrical nanocircuit based on silicon nanowire field-effect transistors (SiNW-FETs) and functionalize it with an individual disordered c-Myc bHLH-LZ domain to enable label-free, in situ, and long-term measurements at the single-molecule level. We use the device to study c-Myc interaction with Max and/or small molecule inhibitors. We observe the self-folding/unfolding process of c-Myc and reveal its interaction mechanism with Max and inhibitors through ultrasensitive real-time monitoring. We capture a relatively stable encounter intermediate ensemble of c-Myc during its transition from the unbound state to the fully folded state. The c-Myc/Max and c-Myc/inhibitor dissociation constants derived are consistent with other ensemble experiments. These proof-of-concept results provide an understanding of the IDP-binding/folding mechanism and represent a promising nanotechnology for IDP conformation/interaction studies and drug discovery.


Assuntos
Sistemas de Liberação de Medicamentos , Proteínas Intrinsicamente Desordenadas/química , Modelos Moleculares , Estrutura Terciária de Proteína , Proteínas Proto-Oncogênicas c-myc/antagonistas & inibidores , Proteínas Proto-Oncogênicas c-myc/química , Ligação Proteica
19.
Dalton Trans ; 52(32): 11243-11253, 2023 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-37526195

RESUMO

Single-molecule magnets (SMMs) have attracted large interest owing to their capability to store information at the level of a single molecule, which has great potential for applications in information technology. The key characteristic required for SMM performance is the magnetization blocking barrier, and in the last decade, impressive efforts have been made to increase its height. Herein, we report an ab initio investigation of the SMM behavior of a series of lanthanide ions (Tb3+, Dy3+, Ho3+, Er3+, Tm3+ and Yb3+) encapsulated in zigzag carbon nanotubes (CNTs) of different diameters. The results show that despite the high symmetry of the Ln environment, none of the investigated systems, except for Er3+ encapsulated in the (7,0) CNT, exhibited any blocking behavior. This is mainly attributed to the strong competition between axial and equatorial contributions to the crystal field of these encapsulated ions, resulting in weak or lack of magnetic axiality. The presented results provide useful theoretical guidance for the design of high-performance SMMs via modulating the crystal field of the ligand environment.

20.
Exploration (Beijing) ; 3(1): 20210233, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37323621

RESUMO

Graphene is a 2D material with fruitful electrical properties, which can be efficiently prepared, tailored, and modified for a variety of applications, particularly in the field of optoelectronic devices thanks to its planar hexagonal lattice structure. To date, graphene has been prepared using a variety of bottom-up growth and top-down exfoliation techniques. To prepare high-quality graphene with high yield, a variety of physical exfoliation methods, such as mechanical exfoliation, anode bonding exfoliation, and metal-assisted exfoliation, have been developed. To adjust the properties of graphene, different tailoring processes have been emerged to precisely pattern graphene, such as gas etching and electron beam lithography. Due to the differences in reactivity and thermal stability of different regions, anisotropic tailoring of graphene can be achieved by using gases as the etchant. To meet practical requirements, further chemical functionalization at the edge and basal plane of graphene has been extensively utilized to modify its properties. The integration and application of graphene devices is facilitated by the combination of graphene preparation, tailoring, and modification. This review focuses on several important strategies for graphene preparation, tailoring, and modification that have recently been developed, providing a foundation for its potential applications.

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