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1.
Small ; 20(19): e2308918, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38149504

RESUMO

Bioinspired tactile devices can effectively mimic and reproduce the functions of the human tactile system, presenting significant potential in the field of next-generation wearable electronics. In particular, memristor-based bionic tactile devices have attracted considerable attention due to their exceptional characteristics of high flexibility, low power consumption, and adaptability. These devices provide advanced wearability and high-precision tactile sensing capabilities, thus emerging as an important research area within bioinspired electronics. This paper delves into the integration of memristors with other sensing and controlling systems and offers a comprehensive analysis of the recent research advancements in memristor-based bionic tactile devices. These advancements incorporate artificial nociceptors and flexible electronic skin (e-skin) into the category of bio-inspired sensors equipped with capabilities for sensing, processing, and responding to stimuli, which are expected to catalyze revolutionary changes in human-computer interaction. Finally, this review discusses the challenges faced by memristor-based bionic tactile devices in terms of material selection, structural design, and sensor signal processing for the development of artificial intelligence. Additionally, it also outlines future research directions and application prospects of these devices, while proposing feasible solutions to address the identified challenges.


Assuntos
Inteligência Artificial , Biônica , Tato , Humanos , Dispositivos Eletrônicos Vestíveis
2.
Chem Soc Rev ; 52(16): 5684-5705, 2023 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-37522252

RESUMO

How far we can push chemical self-assembly is one of the most important scientific questions of the century. Colloidal self-assembly is a bottom-up technique for the rational design of functional materials with desirable collective properties. Due to the programmability of DNA base pairing, surface modification of colloidal particles with DNA has become fundamental for programmable material self-assembly. However, there remains an ever-lasting demand for surface regioselective encoding to realize assemblies that require specific, directional, and orthogonal interactions. Recent advances in surface chemistry have enabled regioselective control over the formation of DNA bonds on the particle surface. In particular, the structural DNA nanotechnology provides a simple yet powerful design strategy with unique regioselective addressability, bringing the complexity of colloidal self-assembly to an unprecedented level. In this review, we summarize the state-of-art advances in DNA-mediated regioselective surface encoding of colloids, with a focus on how the regioselective encoding is introduced and how the regioselective DNA recognition plays a crucial role in the self-assembly of colloidal structures. This review highlights the advantages of DNA-based regioselective modification in improving the complexity of colloidal assembly, and outlines the challenges and opportunities for the construction of more complex architectures with tailored functionalities.


Assuntos
Coloides , DNA , Coloides/química , DNA/química , Nanotecnologia/métodos , Pareamento de Bases
3.
J Neuroinflammation ; 20(1): 87, 2023 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-36997969

RESUMO

Despite extensive astrocyte activation in patients suffering from HIV-associated neurocognitive disorders (HAND), little is known about the contribution of astrocytes to HAND neuropathology. Here, we report that the robust activation of neurotoxic astrocytes (A1 astrocytes) in the CNS promotes neuron damage and cognitive deficits in HIV-1 gp120 transgenic mice. Notably, knockout of α7 nicotinic acetylcholine receptors (α7nAChR) blunted A1 astrocyte responses, ultimately facilitating neuronal and cognitive improvement in the gp120tg mice. Furthermore, we provide evidence that Kynurenic acid (KYNA), a tryptophan metabolite with α7nAChR inhibitory properties, attenuates gp120-induced A1 astrocyte formation through the blockade of α7nAChR/JAK2/STAT3 signaling activation. Meanwhile, compared with gp120tg mice, mice fed with tryptophan showed dramatic improvement in cognitive performance, which was related to the inhibition of A1 astrocyte responses. These initial and determinant findings mark a turning point in our understanding of the role of α7nAChR in gp120-mediated A1 astrocyte activation, opening up new opportunities to control neurotoxic astrocyte generation through KYNA and tryptophan administration.


Assuntos
Infecções por HIV , Ácido Cinurênico , Camundongos , Animais , Ácido Cinurênico/farmacologia , Ácido Cinurênico/metabolismo , Receptor Nicotínico de Acetilcolina alfa7/metabolismo , Astrócitos/metabolismo , Triptofano/metabolismo , HIV/metabolismo , Camundongos Transgênicos , Transtornos Neurocognitivos/metabolismo , Infecções por HIV/complicações , Infecções por HIV/metabolismo
4.
Small ; 19(33): e2301533, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36970781

RESUMO

Laminated graphene film has great potential in compact high-power capacitive energy storage owing to the high bulk density and opened architecture. However, the high-power capability is usually limited by tortuous cross-layer ion diffusion. Herein, microcrack arrays are fabricated in graphene films as fast ion diffusion channels, converting tortuous diffusion into straightforward diffusion while maintaining a high bulk density of 0.92 g cm-3 . Films with optimized microcrack arrays exhibit sixfold improved ion diffusion coefficient and high volumetric capacitance of 221 F cm-3 (240 F g-1 ), representing a critical breakthrough in optimizing ion diffusion toward compact energy storage. This microcrack design is also efficient for signal filtering. Microcracked graphene-based supercapacitor with 30 µg cm-2  mass loading exhibits characteristic frequency up to 200 Hz with voltage window up to 4 V, showing high promise for compact, high-capacitance alternating current (AC) filtering. Moreover, a renewable energy system is conducted using microcrack-arrayed graphene supercapacitors as filter-capacitor and energy buffer, filtering and storing the 50 Hz AC electricity from a wind generator into the constant direct current, stably powering 74 LEDs, demonstrating enormous potential in practical applications. More importantly, this microcracking approach is roll-to-roll producible, which is cost-effective and highly promising for large-scale manufacture.

5.
Langmuir ; 39(40): 14474-14486, 2023 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-37774416

RESUMO

The efficient and safe manipulation of precision materials (such as thin and fragile wafers and glass substrates for flat panel displays) under complicated operating conditions with vacuum, high temperature, and low preload stress is an essential task for pan-semiconductor production lines. However, current manipulation approaches such as suction-based gripping (invalid under vacuum conditions) and mechanical clamping (stress concentration at the contact interfaces) are challenged to satisfy such complex requirements. Herein, fluororubber (FKM) is employed as an adhesive material to overcome such challenges due to its outstanding thermostability, availability under vacuum environments, and high adhesion at low contacting preloads. However, the adhesion of the FKM film decreases significantly with increasing temperature (decrease by 84.83% at 245 °C). Consequently, a micropatterned FKM-based dry adhesive (MFA) fabricated by laser etching is developed. The experimental results reveal that MFAs are efficient in restraining adhesion attenuation at high temperatures (minimum 15% decrease at 245 °C). The numerical analysis and in situ observations reveal the mechanism of the MFAs in restraining adhesion attenuation. The contamination-free and high adhesion at low contacting preload of MFAs can be of great interest in pan-semiconductor production lines that require complicated operating conditions on temperature, vacuum, and interface stress.

6.
Nanotechnology ; 34(17)2023 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-36669170

RESUMO

Atom manufacturing has become a blooming frontier direction in the field of material and chemical science in recent years, focusing on the fabrication of functional materials and devices with individual atoms or with atomic precision. Framework nucleic acids (FNAs) refer to nanoscale nucleic acid framework structures with novel properties distinct from those of conventional nucleic acids. Due to their ability to be precisely positioned and assembled at the nanometer or even atomic scale, FNAs are ideal materials for atom manufacturing. They hold great promise for the bottom-up construction of electronic devices by precisely arranging and integrating building blocks with atomic or near-atomic precision. In this review, we summarize the progress of atom manufacturing based on FNAs. We begin by introducing the atomic-precision construction of FNAs and the intrinsic electrical properties of DNA molecules. Then, we describe various approaches for the fabrication of FNAs templated materials and devices, which are classified as conducting, insulating, or semiconducting based on their electrical properties. We highlight the role of FNAs in the fabrication of functional electronic devices with atomic precision, as well as the challenges and opportunities for atom manufacturing with FNAs.


Assuntos
Ácidos Nucleicos , Ácidos Nucleicos/química , DNA/química , Eletrônica
7.
Cell Mol Biol (Noisy-le-grand) ; 69(11): 227-232, 2023 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-38015518

RESUMO

Water metabolism and actin cytoskeleton remoulding act as essential characters in the process of osteoarthritis (OA). However, the relation between water channel protein aquaporin 1 (AQP1) and actin filament during chondrocytes (CHs) degeneration is not evident. Therefore, the present study aimed to evaluate the role of actin remoulding in the AQP1 mediated CHs degeneration. Primary CHs were collected from human hip cartilage and were degenerated from long-time monolayer culture or IL-1ß stimulation. Besides, the CHs were transfected with AQP1­specific siRNA or vectors to mediate the AQP1 gene expression. The potent inhibitor of actin polymerization Cytochalasin D was also supplemented during culture. RT-PCR was performed to determine the relative gene expression. AQP1 and F-actin fluorescence staining were performed to determine the AQP1 and F-actin organization. Moreover, the cell area and viability were also analyzed. AQP1 and F-actin organization were both increased during seven days' CHs culture or three days' IL-1ß stimulation. Silencing of AQP1 prevented the cell area spreading and degenerated phenotype of CHs with suppression of F-actin aggregation in both natural or IL-1ß-caused inflammatory-related degeneration. Besides, upregulating the AQP1 in the CHs via gene editing promoted the cell area spreading, and F-actin accumulation, and accelerated the CHs degeneration, which can be alleviated by Cytochalasin D treatment. These findings suggested that AQP1-mediated human CHs degeneration is related to F-actin aggregation.


Assuntos
Actinas , Aquaporina 1 , Humanos , Citoesqueleto de Actina , Actinas/genética , Aquaporina 1/genética , Condrócitos , Citocalasina D/farmacologia
8.
BMC Med Imaging ; 23(1): 12, 2023 01 21.
Artigo em Inglês | MEDLINE | ID: mdl-36681824

RESUMO

BACKGROUND: The combination of anti-programmed death-1 antibodies and chemotherapy is effective; however, there are no reliable outcome prediction factors. We investigated the prognostic factors based on 18Fluorine-fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG PET/CT) quantitative and hematological parameters to predict progression-free survival (PFS) in relapsed/refractory classical Hodgkin lymphoma (R/R cHL) patients treated with immune checkpoint inhibitors (ICIs) and chemotherapy. METHODS: This retrospective study included 31 patients who underwent 18F-FDG PET/CT before and during treatment. Pretreatment metabolic and hematological parameters were evaluated using Cox regression analysis to identify predictors of PFS. Based on the cut-off values calculated using the receiver operating characteristic (ROC) curve, patients were classified into low-, intermediate-, and high-risk groups. Kaplan-Meier curves and the log-rank test were used to compare survival differences between the groups. RESULTS: Cox multivariable analysis indicted that the treatment response based on Lactate dehydrogenase (LDH), Lugano classification and SUVmax were independent predictors of PFS (P = 0.004, 0.007 and 0.039, respectively). The optimal cut-off values for SUVmax and LDH were 11.62 and 258.5 U/L, respectively (P < 0.01). Survival curves showed that LDH ≥ 258.5U/L and SUVmax ≥ 11.62 were correlated to shorter PFS (P < 0.001, P = 0.003, respectively). The differences in PFS between the low-, intermediate-, and high-risk groups were statistically significant (P = 0.0043). CONCLUSION: In R/R cHL patients treated with ICIs and chemotherapy, Lugano classification, SUVmax, and LDH were significantly correlated with PFS. The combination of metabolic and hematological parameters predicts PFS and may help to improve patient selection.


Assuntos
Doença de Hodgkin , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Humanos , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada/métodos , Prognóstico , Fluordesoxiglucose F18/metabolismo , Doença de Hodgkin/diagnóstico por imagem , Doença de Hodgkin/tratamento farmacológico , Inibidores de Checkpoint Imunológico/uso terapêutico , Estudos de Coortes , Estudos Retrospectivos , Recidiva Local de Neoplasia
9.
Appl Intell (Dordr) ; : 1-18, 2023 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-37363387

RESUMO

Spreading malicious rumors on social networks such as Facebook, Twitter, and WeChat can trigger political conflicts, sway public opinion, and cause social disruption. A rumor can spread rapidly across a network and can be difficult to control once it has gained traction.Rumor influence minimization (RIM) is a central problem in information diffusion and network theory that involves finding ways to minimize rumor spread within a social network. Existing research on the RIM problem has focused on blocking the actions of influential users who can drive rumor propagation. These traditional static solutions do not adequately capture the dynamics and characteristics of rumor evolution from a global perspective. A deep reinforcement learning strategy that takes into account a wide range of factors may be an effective way of addressing the RIM challenge. This study introduces the dynamic rumor influence minimization (DRIM) problem, a step-by-step discrete time optimization method for controlling rumors. In addition, we provide a dynamic rumor-blocking approach, namely RLDB, based on deep reinforcement learning. First, a static rumor propagation model (SRPM) and a dynamic rumor propagation model (DRPM) based on of independent cascade patterns are presented. The primary benefit of the DPRM is that it can dynamically adjust the probability matrix according to the number of individuals affected by rumors in a social network, thereby improving the accuracy of rumor propagation simulation. Second, the RLDB strategy identifies the users to block in order to minimize rumor influence by observing the dynamics of user states and social network architectures. Finally, we assess the blocking model using four real-world datasets with different sizes. The experimental results demonstrate the superiority of the proposed approach on heuristics such as out-degree(OD), betweenness centrality(BC), and PageRank(PR).

10.
J Am Chem Soc ; 144(14): 6311-6320, 2022 04 13.
Artigo em Inglês | MEDLINE | ID: mdl-35353520

RESUMO

Nanozymes have emerged as a class of novel catalytic nanomaterials that show great potential to substitute natural enzymes in various applications. Nevertheless, spatial organization of multiple subunits in a nanozyme to rationally engineer its catalytic properties remains to be a grand challenge. Here, we report a DNA-based approach to encode the organization of gold nanoparticle clusters (GNCs) for the construction of programmable enzyme equivalents (PEEs). We find that single-stranded (ss-) DNA scaffolds can self-fold into nanostructures with prescribed poly-adenine (polyA) loops and double-stranded stems and that the polyA loops serve as specific sites for seed-free nucleation and growth of GNCs with well-defined particle numbers and interparticle spaces. A spectrum of GNCs, ranging from oligomers with discrete particle numbers (2-4) to polymer-like chains, are in situ synthesized in this manner. The polymeric GNCs with multiple spatially organized nanoparticles as subunits show programmable peroxidase-like catalytic activity that can be tuned by the scaffold size and the inter-polyA spacer length. This study thus opens new routes to the rational design of nanozymes for various biological and biomedical applications.


Assuntos
Nanopartículas Metálicas , Nanoestruturas , Catálise , DNA de Cadeia Simples , Ouro/química , Nanopartículas Metálicas/química , Nanoestruturas/química
11.
Artigo em Inglês | MEDLINE | ID: mdl-35762663

RESUMO

BACKGROUND: 99Tcm-MDP SPECT/CT is widely used to diagnose early bone metastasis. Ribs are high-risk bone metastasis sites, while few study is related to ribs. The study is to investigate the risk factors of rib metastases in lung cancer patients. METHODS: We retrospectively analyzed the patients' clinical characteristics and SPECT/CT imaging features. The patients were divided into a rib metastasis group (108 cases) and a non-rib metastasis group (103 cases). RESULTS: In 211 patients, rib metastases were closely related to tumor markers, T stage, N stage, clinical staging, lymph node involvement, number of rib foci, localization on rib and foci type (P < 0.05). In 93 patients with pure rib foci, rib metastases were affected by clinical staging, lymph node involvement, localization on the rib and primary lung cancer localization (P < 0.001, 0.038, < 0.001, 0.034, respectively). In 100 patients with a solitary rib focus, rib metastases were associated with clinical staging, localization on the rib, and lymph node involvement (P < 0.001, 0.001, and 0.014, respectively). In all 633 rib foci, localization on the rib was an effective risk factor for rib metastases (P < 0.001). CONCLUSIONS: Patients with increased tumor markers, stage IV lung adenocarcinoma and multiple rib foci located ipsilaterally with the primary lung tumor, or rib foci accompanied other bone foci are more likely to develop rib metastasis. Patients with pure rib foci or a solitary rib focus, especially in the anterior rib with negative lymph node involvement, have a low probability of rib metastasis.

12.
Nano Lett ; 21(13): 5689-5696, 2021 07 14.
Artigo em Inglês | MEDLINE | ID: mdl-34181434

RESUMO

The nucleolus is a central hub for coordinating cellular stress responses during cancer development and treatment. Accurate identification of nucleolar stress response is crucially desired for nucleolus-based diagnostics and therapeutics but technically challenging due to the need to address the ultrastructural analysis. Here, we report a protein-like CD with the integration of fluorescent blinking domains and RNA-binding motifs, which offers the ability to perform enhanced super-resolution imaging of the nucleolar ultrastructure. This image allows extraction of multidimensional information from the nucleolus for accurate distinguishment of different cells from the same cell types. Furthermore, we demonstrate for the first time this CD-depicted nucleolar ultrastructure as a sensitive hallmark to identify and discriminate subtle responses to various stressors as well as to afford RNA-related information that has been inaccessible by conventional immunofluorescence methods. This protein-mimicking CD could become a broadly useful probe for nucleolar stress studies in cell diagnostics and therapeutics.


Assuntos
Carbono , Nucléolo Celular , Proteínas Nucleares , RNA
13.
J Minim Access Surg ; 18(4): 510-518, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35046173

RESUMO

Background: Surgery is the mainstay of treatment for gastric gastrointestinal stromal tumours (GIST). However, the choice of surgical approach for gastric GIST remains controversial. Aims and Objectives: To evaluate the short- and long-term efficacies of laparoscopic surgery versus conventional open surgery for gastric GIST. Materials and Methods: We retrospectively reviewed 148 patients with gastric GIST at our hospital between January 2013 and January 2020. The patients were categorised into the following two groups based on the surgery performed: The laparoscopic surgery group (LG) and the open surgery group (OG). Differences in the tumour size, surgical procedures and modified National Institutes of Health classification were statistically significant. To balance the intergroup confounders, we performed 1:1 propensity score matching (PSM). Results: A total of 104 patients were selected after PSM (52 in each group). We focused on the short- and long- term outcomes of patients. The baseline information was balanced between the two groups after PSM. The LG benefited from the advantages of a minimally invasive surgery (faster gastrointestinal function recovery, shorter time to drainage tube removal, less blood loss and shorter hospitalisation period), however, it also had high treatment costs. Moreover, both laparoscopic and open surgeries resulted in similar intra-operative and post-operative complications rates, overall survival time and disease-free survival time. Conclusion: Laparoscopic resection is feasible and oncologically safe for GIST. However, more prospective studies are required to confirm the findings.

14.
Angew Chem Int Ed Engl ; 61(11): e202114190, 2022 03 07.
Artigo em Inglês | MEDLINE | ID: mdl-34962699

RESUMO

Integrating dissimilar materials at the nanoscale is crucial for modern electronics and optoelectronics. The structural DNA nanotechnology provides a universal platform for precision assembly of materials; nevertheless, heterogeneous integration of dissimilar materials with DNA nanostructures has yet to be explored. We report a DNA origami-encoded strategy for integrating silica-metal heterostructures. Theoretical and experimental studies reveal distinctive mechanisms for the binding and aggregation of silica and metal clusters on protruding double-stranded DNA (dsDNA) strands that are prescribed on the DNA origami template. In particular, the binding energy differences of silica/metal clusters and DNA molecules underlies the accessibilities of dissimilar material areas on DNA origami. By programming the densities and lengths of protruding dsDNA strands on DNA origami, silica and metal materials can be independently deposited at their predefined areas with a high vertical precision of 2 nm. We demonstrate the integration of silica-gold and silica-silver heterostructures with high site addressability. This DNA nanotechnology-based strategy is thus applicable for integrating various types of dissimilar materials, which opens up new routes to bottom-up electronics.

15.
J Cell Physiol ; 236(1): 107-120, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33459391

RESUMO

Stem cells play pivotal roles in esophageal squamous cell carcinoma (ESCC) recurrence and metastasis. The self-renewal ability of stem cells was associated with specific microRNAs (miRs). Herein, we identified the effects of miR-377 on ESCC stem cell activities. First, the expression of miR-377 in ESCC and adjacent normal tissues was determined. The relationship between miR-377 and chromobox protein homolog 3 (CBX3) was assessed by a dual-luciferase reporter gene assay. miR-377 was overexpressed or inhibited in ESCC stem cells to explore its role in ESCC. To further investigate the mechanism of miR-377 in ESCC, cells were introduced with short hairpin RNA against CBX3 or pifithrin-α (inhibitor of P53 pathway). Besides, the expression of P21, P53, CD133, CD13, Nanog, sex determining region Y-Box 2 (Sox2), and octamer-binding transcription factor 4 (Oct4), cell sphere formation, colony formation, and proliferation were evaluated respectively. Finally, limiting dilution assay in vivo and tumor xenograft in nude mice were conducted to confirm the roles of miR-377 in vivo. miR-377 was poorly expressed in ESCC. Overexpression of miR-377 could suppress the stem-like trait of ESCC as well as the tumor growth in vivo. miR-377 targeted CBX3 to activate the P53/P21 pathway. Besides, the expression of stem-like markers including CD133, CD13, Oct4, Sox2, and Nanog was decreased, and the abilities of cell sphere formation, colony formation, proliferation, and tumorigenicity were significantly reduced by overexpressing miR-377 or silencing CBX3. The results were reversed after inactivating the P53/P21 pathway. In summary, upregulation of miR-377 inhibits the self-renewal of ESCC stem cells by inhibiting CBX3 expression and promoting activation of the P53/P21 pathway.


Assuntos
Proteínas Cromossômicas não Histona/genética , Inibidor de Quinase Dependente de Ciclina p21/genética , Neoplasias Esofágicas/genética , Carcinoma de Células Escamosas do Esôfago/genética , MicroRNAs/genética , Proteína Supressora de Tumor p53/genética , Animais , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Feminino , Regulação Neoplásica da Expressão Gênica/genética , Humanos , Masculino , Camundongos , Camundongos Endogâmicos NOD , Camundongos Nus , Camundongos SCID , Pessoa de Meia-Idade , Transdução de Sinais/genética , Regulação para Cima/genética
16.
Anal Chem ; 93(8): 3968-3975, 2021 03 02.
Artigo em Inglês | MEDLINE | ID: mdl-33599499

RESUMO

Accurate counting of single molecules at nanoscale resolution is essential for the study of molecular interactions and distribution in subcellular fractions. By using small-sized carbon dots (CDs), we have now developed a quantitative single-molecule localization microscopy technique (qSMLM) based on spontaneous blinking to count single molecules with a localization precision of 10 nm, which can be accomplished on conventional microscopes without sophisticated laser control. We explore and adapt the blinking of CDs with diverse structures and demonstrate a counting accuracy of >97% at a molecular density of 500 per µm2. When applied to G-protein coupled receptors on a cell membrane, we discriminated receptor oligomerization and clustering and revealed ligand-regulated receptor distribution patterns. This is the first example of adapting nanoparticle self-blinking for molecular counting, and this demonstrates the power of CDs as SMLM probes to reliably decipher sub-diffraction structures that mediate crucial biological functions.


Assuntos
Carbono , Nanopartículas , Piscadela , Microscopia , Imagem Individual de Molécula
17.
Anal Chem ; 2021 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-34132089

RESUMO

Single-molecule fluorescence imaging is a powerful tool to study protein function by tracking molecular position and distribution, but the precise and rapid identification of dynamic molecules remains challenging due to the heterogeneous distribution and interaction of proteins on the live cell membrane. We now develop a deep-learning (DL)-assisted single-molecule imaging method that can precisely distinguish the monomer and complex for rapid and real-time tracking of protein interaction. This DL-based model, which comprises convolutional layers, max pooling layers, and fully connected layers, is trained to reach an accuracy of >98% for identifying monomer and complex. We use this method to investigate the dynamic process of chemokine receptor CXCR4 on the live cell membrane during the early signaling stage. The results show that, upon ligand activation, the CXCR4 undergoes a dynamic process of forming a receptor complex. We further demonstrate that the CXCR4 complex tends to be internalized at 2.5-fold higher rate into the cell interior than the monomer via the clathrin-dependent pathway. This study is the first example to scrutinize the early signaling process of CXCR4 at the single-molecule level on the live cell membrane. We envision that this DL-assisted imaging method would be a broadly useful technique to study more protein families for elucidating their physiological and pathological functions.

18.
BMC Plant Biol ; 21(1): 408, 2021 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-34493199

RESUMO

BACKGROUND: Mung bean (Vigna radiata) is a warm-season legume crop and belongs to the papilionoid subfamily of the Fabaceae family. China is the leading producer of mung bean in the world. Mung bean has significant economic and health benefits and is a promising species with broad adaptation ability and high tolerance to environmental stresses. OSCA (hyperosmolality-gated calcium-permeable channel) gene family members play an important role in the modulation of hypertonic stress, such as drought and salinity. However, genome-wide analysis of the OSCA gene family has not been conducted in mung bean. RESULTS: We identified a total of 13 OSCA genes in the mung bean genome and named them according to their homology with AtOSCAs. All the OSCAs were phylogenetically split into four clades. Phylogenetic relationship and synteny analyses showed that the VrOSCAs in mung bean and soybean shared a relatively conserved evolutionary history. In addition, three duplicated VrOSCA gene pairs were identified, and the duplicated VrOSCAs gene pairs mainly underwent purifying selection pressure during evolution. Protein domain, motif and transmembrane analyses indicated that most of the VrOSCAs shared similar structures with their homologs. The expression pattern showed that except for VrOSCA2.1, the other 12 VrOSCAs were upregulated under treatment with ABA, PEG and NaCl, among which VrOSCA1.4 showed the largest increased expression levels. The duplicated genes VrOSCA2.1/VrOSCA2.2 showed divergent expression, which might have resulted in functionalization during subsequent evolution. The expression profiles under ABA, PEG and NaCl stress revealed a functional divergence of VrOSCA genes, which agreed with the analysis of cis-acting regulatory elements in the promoter regions of VrOSCA genes. CONCLUSIONS: Collectively, the study provided a systematic analysis of the VrOSCA gene family in mung bean. Our results establish an important foundation for functional and evolutionary analysis of VrOSCAs and identify genes for further investigation of their ability to confer abiotic stress tolerance in mung bean.


Assuntos
Osmorregulação/genética , Proteínas de Plantas/genética , Vigna/fisiologia , Ácido Abscísico/farmacologia , Arabidopsis/genética , Duplicação Gênica , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Genoma de Planta , Estudo de Associação Genômica Ampla , Família Multigênica , Oryza/genética , Pressão Osmótica , Filogenia , Proteínas de Plantas/metabolismo , Regiões Promotoras Genéticas , Cloreto de Sódio/farmacologia , Glycine max/genética , Estresse Fisiológico/genética , Sintenia , Vigna/efeitos dos fármacos , Vigna/genética
19.
Nat Mater ; 19(7): 781-788, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-31873228

RESUMO

Nature has evolved strategies to encode information within a single biopolymer to program biomolecular interactions with characteristic stoichiometry, orthogonality and reconfigurability. Nevertheless, synthetic approaches for programming molecular reactions or assembly generally rely on the use of multiple polymer chains (for example, patchy particles). Here we demonstrate a method for patterning colloidal gold nanoparticles with valence bond analogues using single-stranded DNA encoders containing polyadenine (polyA). By programming the order, length and sequence of each encoder with alternating polyA/non-polyA domains, we synthesize programmable atom-like nanoparticles (PANs) with n-valence that can be used to assemble a spectrum of low-coordination colloidal molecules with different composition, size, chirality and linearity. Moreover, by exploiting the reconfigurability of PANs, we demonstrate dynamic colloidal bond-breaking and bond-formation reactions, structural rearrangement and even the implementation of Boolean logic operations. This approach may be useful for generating responsive functional materials for distinct technological applications.


Assuntos
Engenharia Química , DNA de Cadeia Simples/química , Nanopartículas Metálicas/química , Coloides/química , Ouro/química
20.
J Hum Genet ; 66(4): 347-357, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32968204

RESUMO

To explore whether DNA methylation of the ATP-binding cassette G1 (ABCG1) gene and its dynamic change are associated with incident type 2 diabetes mellitus (T2DM). We conducted a nested case-control study with 286 pairs of T2DM cases and matched controls nested in the Rural Chinese Cohort Study. Conditional logistic regression models were used to estimate odds ratios (ORs) and 95% confidence intervals (CIs) for incident T2DM risk according to ABCG1 methylation level at baseline and its dynamic change at follow-up examination. Spearman's rank correlation coefficients were used to analyze the association between ABCG1 methylation and its possible risk factors in the control group. We found that T2DM risk increased by 16% (OR = 1.16, 95% CI = 1.02-1.31) with each 1% increase in DNA methylation levels of the ABCG1 loci CpG13 and CpG14. DNA methylation change of the ABCG1 locus CpG15 during the 6-year follow-up was associated with increased T2DM risk: T2DM risk increased by 78% in the upper tertile group (methylation gain ≥5%) versus lower tertile group (methylation gain <1%) (OR = 1.78, 95% CI = 1.01-3.15). Furthermore, body mass index was positively correlated with the DNA methylation level of the ABCG1 loci CpG13, CpG14 and CpG15. In conclusion, DNA methylation levels of the ABCG1 loci CpG13 and CpG14 and the methylation gain of locus CpG15 were positively associated with incident T2DM risk, which may suggest a possible etiologic pattern for T2DM and potentially improve T2DM prediction in rural Chinese people.


Assuntos
Membro 1 da Subfamília G de Transportadores de Cassetes de Ligação de ATP/genética , Povo Asiático/genética , Metilação de DNA , Diabetes Mellitus Tipo 2/epidemiologia , Diabetes Mellitus Tipo 2/genética , Glicemia/análise , Índice de Massa Corporal , Estudos de Casos e Controles , China , Estudos de Coortes , Diabetes Mellitus Tipo 2/patologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Risco
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