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1.
RSC Med Chem ; 15(3): 856-873, 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38516590

RESUMO

Three series of benzoheterocyclic-substituted amide derivatives were designed and synthesized as potent ASK1 inhibitors in this work. After undergoing continuous structural optimization, compound 17a was discovered to be a novel inhibitor of ASK1 with good potency (kinase, IC50 = 26 nM), noteworthy liver microsomal stability (human, T1/2 = 340.4 min), good pharmacokinetic parameters (rat, T1/2 p.o. = 2.11 h, AUClast p.o. = 10 900 h ng mL-1) and high oral bioavailability (rat, F = 97.9%), while also being inactive towards hERG (IC50 > 10 µM).

2.
Sci Rep ; 14(1): 4710, 2024 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-38409463

RESUMO

A rotary motor combined with fibrous string demonstrates excellent performance because it is powerful, lightweight, and prone to large strokes; however, the stiffness range and force-generating capability of twisted string transmission systems are limited. Here, we present a variable stiffness artificial muscle generated by impregnating shear stiffening gels (STGs) into a twisted string actuator (TSA). A high twisting speed produces a large impact force and causes shear stiffening of the STG, thereby improving the elasticity, stiffness, force capacity, and response time of the TSA. We show that at a twisting speed of 4186 rpm, the elasticity of an STG-TSA reached 30.92 N/mm, whereas at a low twisting speed of 200 rpm, it was only 10.51 N/mm. In addition, the STG-TSA exhibited a more prominent shear stiffening effect under a high stiffness load. Our work provides a promising approach for artificial muscles to coactivate with human muscles to effectively compensate for motion.

3.
Soft Robot ; 2024 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-38407843

RESUMO

Bio-syncretic robots consisting of artificial structures and living muscle cells have attracted much attention owing to their potential advantages, such as high drive efficiency, miniaturization, and compatibility. Motion controllability, as an important factor related to the main performance of bio-syncretic robots, has been explored in numerous studies. However, most of the existing bio-syncretic robots still face challenges related to the further development of steerable kinematic dexterity. In this study, a bionic optimized biped fully soft bio-syncretic robot actuated by two muscle tissues and steered with a direction-controllable electric field generated by external circularly distributed multiple electrodes has been developed. The developed bio-syncretic robot could realize wirelessly steerable motion and effective transportation of microparticle cargo on artificial polystyrene and biological pork tripe surfaces. This study may provide an effective strategy for the development of bio-syncretic robots and other related studies, such as nonliving soft robot design and muscle tissue engineering.

4.
Soft Robot ; 2024 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-38237109

RESUMO

Previous research on wearable robotics focused on developing actuation mechanisms while overlooking influences of skin movement. During finger flexion, skins on the opisthenar and finger back are stretched. Impeding such skin movement will obstruct normal finger motions. In this research, a statistical study on skin movement is proposed and conducted to quantify skin movement on human hands. Results of 30 subjects (15 men and 15 women) reveal that skin at the finger back extends by an average of 29.3 ± 7.2% in fist clenching. Based on this study, design guidelines for robotic gloves are proposed, and nominal strain values at different hand regions are tabulated for references in robotic glove design. To explore the influence of skin movement on wearable robotics, an elastomer-constrained flat tube actuator is proposed based on which two prototype robotic gloves are developed: one with an ergonomic strap interface that has small constraint to skin motion, and the other based on the commonly used fabric glove that is supposed to have large constraint to skin motion. With the same power input to the robotic gloves, the strap-based design achieves a finger motion range of 2.5 times and a gripping force of 4.3 times that of the conventional fabric glove.

5.
Nature ; 625(7994): 270-275, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38200301

RESUMO

Supersolid, an exotic quantum state of matter that consists of particles forming an incompressible solid structure while simultaneously showing superfluidity of zero viscosity1, is one of the long-standing pursuits in fundamental research2,3. Although the initial report of 4He supersolid turned out to be an artefact4, this intriguing quantum matter has inspired enthusiastic investigations into ultracold quantum gases5-8. Nevertheless, the realization of supersolidity in condensed matter remains elusive. Here we find evidence for a quantum magnetic analogue of supersolid-the spin supersolid-in the recently synthesized triangular-lattice antiferromagnet Na2BaCo(PO4)2 (ref. 9). Notably, a giant magnetocaloric effect related to the spin supersolidity is observed in the demagnetization cooling process, manifesting itself as two prominent valley-like regimes, with the lowest temperature attaining below 100 mK. Not only is there an experimentally determined series of critical fields but the demagnetization cooling profile also shows excellent agreement with the theoretical simulations with an easy-axis Heisenberg model. Neutron diffractions also successfully locate the proposed spin supersolid phases by revealing the coexistence of three-sublattice spin solid order and interlayer incommensurability indicative of the spin superfluidity. Thus, our results reveal a strong entropic effect of the spin supersolid phase in a frustrated quantum magnet and open up a viable and promising avenue for applications in sub-kelvin refrigeration, especially in the context of persistent concerns about helium shortages10,11.

6.
Lung Cancer ; 188: 107468, 2024 02.
Artigo em Inglês | MEDLINE | ID: mdl-38181454

RESUMO

BACKGROUND: MET and AXL dysregulations are implicated in acquired resistance to EGFR-TKIs in NSCLC. But consensus on the optimal definition for MET/AXL dysregulations in EGFR-mutant NSCLC is lacking. Here, we investigated the efficacy and tolerability of ningetinib (a MET/AXL inhibitor) plus gefitinib in EGFR-mutant NSCLC, and evaluated the clinical relevance of MET/AXL dysregulations by different definitions. METHODS: Patients in this phase 1b dose-escalation/dose-expansion trial received ningetinib 30 mg/40 mg/60 mg plus gefitinib 250 mg once daily. Primary endpoints were tolerability (dose-escalation) and objective response rate (dose-expansion). MET/AXL status were analyzed using FISH and IHC. RESULTS: Between March 2017 and January 2021, 108 patients were enrolled. The proportion of MET focal amplification, MET polysomy, MET overexpression, AXL amplification and AXL overexpression is 18.1 %, 5.6 %, 55.8 %, 8.1 % and 45.3 %, respectively. 6.8 % patients have concurrent MET amplification and AXL overexpression. ORR is 30.8 % for tumors with MET amplification, 0 % for MET polysomy, 24.1 % for MET overexpression, 20 % for AXL amplification and 27.6 % for AXL overexpression. For patients with concurrent MET amplification and AXL overexpression, ningetinib plus gefitinib provides an ORR of 80 %, DCR of 100 % and median PFS of 4.7 months. Tumors with higher MET copy number and AXL expression tend to have higher likelihood of response. Biomarker analyses show that MET focal amplification and overexpression are complementary in predicting clinical benefit from MET inhibition, while AXL dysregulations defined by an arbitrary level may dilute the efficacy of AXL blockade. CONCLUSIONS: This study demonstrates that combined blockade of MET, AXL and EGFR is a feasible strategy for a subset of EGFR-mutant NSCLC. TRIAL REGISTRATION: Chinadrugtrials.org.cn, CTR20160875.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Humanos , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Gefitinibe/uso terapêutico , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Proteínas Proto-Oncogênicas c-met/genética , Proteínas Proto-Oncogênicas c-met/metabolismo , Receptores ErbB/genética , Receptores ErbB/metabolismo , Mutação/genética , Inibidores de Proteínas Quinases/uso terapêutico , Inibidores de Proteínas Quinases/farmacologia , Biomarcadores
7.
IEEE Trans Nanobioscience ; 23(2): 242-251, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37676797

RESUMO

Since the COVID-19 disease has been further aggravated, the prevention of pathogen transmission becomes a vital issue to restrain casualties. Recent research outcomes have shown the possibilities of the viruses existing on inanimate surfaces up to few days, which carry the risk of touch propagation of the disease. Deep ultraviolet germicide irradiation (UVGI) with the wavelength of 255-280nm has been verified to efficiently disinfect various types of bacteria and virus, which could prevent the aggravation of pandemic spread. Even though considerable experiments and approaches have been applied to evaluate the disinfection effects, there are only few reports about how the individual bio-organism behaves after ultraviolet C (UVC) irradiation, especially in the aspect of mechanical changes. Furthermore, since the standard pathway of virus transmission and reproduction requires the host cell to assemble and transport newly generated virus, the dynamic response of infectious cell is always the vital aspect of virology study. In this work, high power LEDs array has been established with 270nm UVC irradiation to evaluate disinfection capability on various types of bio-organism, and incubator embedded atomic force microscopy (AFM) is used to investigate the single bacterium and virus under UVGI. The real-time tracking of the living Vero cells infected with adenovirus has also been presented in this study. The results show that after sufficient UVGI, the outer shell of bacteria and viruses remain intact in structure, however the bio-organisms lost the capability of reproduction and normal metabolism. The experiment results also indicate that once the host cell is infected with adenovirus, the rapid production of newborn virus capsid will gradually destroy the cellular normal metabolism and lose mechanical integrity.


Assuntos
Desinfecção , Vírus , Humanos , Chlorocebus aethiops , Recém-Nascido , Animais , Desinfecção/métodos , Células Vero , Raios Ultravioleta , Bactérias , Biomarcadores
8.
Quant Imaging Med Surg ; 13(12): 8587-8598, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-38106337

RESUMO

Background: Ultrasonography of the uterine artery (UtA) in the first and second trimesters of pregnancy can assess uterine-placental blood perfusion and guide early clinical prevention. Establishing normal ranges of the UtA pulsatility index (UtA-PI) at 11-14 weeks of pregnancy is helpful for the early identification of high-risk pregnant women and improving the prognosis. This study aimed to establish a reference range of UtA-PI based on crown-rump length (CRL) for spontaneous and in vitro fertilization (IVF) singleton pregnancy during 11-14 weeks, respectively. Methods: A prospective study was performed at Peking Union Medical College Hospital. Healthy, low-risk women with a singleton pregnancy at 11-14 gestational weeks were consecutively recruited for this study from December 2017 to December 2020. All participants underwent routine prenatal ultrasound examination. The CRL of the fetus and the UtA-PI were measured in both uterine arteries, and average values were calculated. The LMS method was used to fit the percentile (P)5, P10, P25, P50, P75, P90, and P95 curves of the UtA-PI value of spontaneous and IVF singleton pregnancy with CRL changes, respectively. Results: A total of 1,962 pregnant women with normal fetuses were included in this study, including 1,792 pregnancies conceived naturally and 170 IVF fetuses. The UtA-PI reference range in the spontaneous pregnancy group was consistently higher than that in the IVF group during 11-14 weeks, and showed a statistically significant difference in UtA-PI for spontaneous and IVF pregnancies (P<0.001). According to the LMS method, each percentile curve of UtA-PI decreased with the increase of CRL in both the natural pregnancy group and the IVF group. The P95 range of UtA-PI for pregnant women with naturally conceived and IVF pregnancy was 2.74 to 2.11 and 2.50 to 1.94, respectively. The overall change of UtA-PI differentials of the two groups showed a downward trend and decreased slightly with the increase of CRL. Conclusions: This study provided a single-center, large sample of data and constructed a CRL-based reference value of UtA-PI for spontaneous and IVF singleton pregnancy, which provides a reliable basis for early UtA evaluation and early clinical decision-making during 11-14 gestational weeks.

9.
Phys Rev Lett ; 131(11): 116702, 2023 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-37774260

RESUMO

Inspired by recent experimental measurements [Guo et al., Phys. Rev. Lett. 124, 206602 (2020PRLTAO0031-900710.1103/PhysRevLett.124.206602); Jiménez et al., Nature (London) 592, 370 (2021)NATUAS0028-083610.1038/s41586-021-03411-8] on frustrated quantum magnet SrCu_{2}(BO_{3})_{2} under combined pressure and magnetic fields, we study the related spin-1/2 Shastry-Sutherland model using state-of-the-art tensor network methods. By calculating thermodynamics, correlations, and susceptibilities, we find, in zero magnetic field, not only a line of first-order dimer-singlet to plaquette-singlet phase transition ending with a critical point, but also signatures of the ordered plaquette-singlet transition with its critical end point terminating on this first-order line. Moreover, we uncover prominent magnetic barocaloric responses, a novel type of quantum correlation induced cooling effect, in the strongly fluctuating supercritical regime. Under finite fields, we identify a quantum phase transition from the plaquette-singlet phase to the spin supersolid phase that breaks simultaneously lattice translational and spin rotational symmetries. The present findings on the Shastry-Sutherland model are accessible in current experiments and would shed new light on the critical and supercritical phenomena in the archetypal frustrated quantum magnet SrCu_{2}(BO_{3})_{2}.

10.
Natl Sci Rev ; 10(8): nwad183, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37560444

RESUMO

The underlying principle of the unique dynamic adaptive adhesion capability of a rock-climbing fish (Beaufortia kweichowensis) that can resist a pull-off force of 1000 times its weight while achieving simultaneous fast sliding (7.83 body lengths per second (BL/S)) remains a mystery in the literature. This adhesion-sliding ability has long been sought for underwater robots. However, strong surface adhesion and fast sliding appear to contradict each other due to the need for high surface contact stress. The skillfully balanced mechanism of the tight surface adhesion and fast sliding of the rock-climbing fish is disclosed in this work. The Stefan force (0.1 mN/mm2) generated by micro-setae on pectoral fins and ventral fins leads to a 70 N/m2 adhesion force by conforming the overall body of the fish to a surface to form a sealing chamber. The pull-off force is neutralized simultaneously due to the negative pressure caused by the volumetric change of the chamber. The rock-climbing fish's micro-setae hydrodynamic interaction and sealing suction cup work cohesively to contribute to low friction and high pull-off-force resistance and can therefore slide rapidly while clinging to the surface. Inspired by this unique mechanism, an underwater robot is developed with incorporated structures that mimic the functionality of the rock-climbing fish via a micro-setae array attached to a soft self-adaptive chamber, a setup which demonstrates superiority over conventional structures in terms of balancing tight underwater adhesion and fast sliding.

11.
J Colloid Interface Sci ; 650(Pt B): 1983-1992, 2023 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-37527603

RESUMO

Developing a high-efficiency photoelectrochemical (PEC) electrode for the glycerol oxidation reaction (GOR) is important for producing valuable products. The PEC performance could be enhanced by rationally designing heterostructures with inhibited recombination of charge carriers. Nevertheless, the interface electronic structure of heterostructures has not been comprehensively analyzed. In this work, the PEC GOR performance of ZnIn2S4/TiO2 heterostructure photoanode showed 1.7 folds enhancement than that of pure TiO2 photoanode at 1.23 V vs. RHE. The ZnIn2S4/TiO2 heterostructure was simulated by constructing ZnIn2S4 on the TiO2 single crystal, which was beneficial for investigating the interface electronic structure of heterostructure. Single-particle spectroscopy demonstrated a significantly increased lifetime of charge carriers. Combined with the in-situ X-ray photoelectron spectroscopy, Kelvin probe force microscopy, work function, and electron paramagnetic resonance, the interface electronic structure of the ZnIn2S4/TiO2 heterostructure was proposed with a Z-scheme mechanism. This work provides a comprehensive strategy for analyzing the interface electronic structure of heterostructures.

12.
ISA Trans ; 141: 44-51, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37541856

RESUMO

With the rapid advancement of cloud-native computing, the microservice with high concurrency and low coupling has ushered in an unprecedented period of vigorous development. However, due to the mutability and complexity of cooperation procedures, it is difficult to realize high-efficient security management on these microservices. Traditional centralized access control has the defects of relying on a centralized cloud manager and a single point of failure. Meanwhile, decentralized mechanisms are defective by inconsistent policies defined by different participants. This paper first proposes a blockchain-based distributed access control policies and scheme, especially for microservices cooperation with dynamic access policies. We store the authorized security policies on the blockchain to solve the inconsistent policy problem while enabling individual management of personalized access policies by the providers rather than a central authority. Then we propose a graph-based decision-making scheme to achieve an efficient access control for microservices cooperation. Through the evaluations and experiments, it shows that our solution can realize effective distributed access control at an affordable cost.

13.
Molecules ; 28(13)2023 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-37446696

RESUMO

Ruthenium (Ru)-based organometallic drugs have gained attention as chemotherapeutic and bioimaging agents due to their fewer side effects and excellent physical optical properties. Tuning the electronic structures of Ru complexes has been proven to increase the cytotoxicity of cancer cells and the luminescent efficiency of the analytical probes. However, the relationship between electronic structures and bioactivities is still unclear due to the potential enhancement of both electron donor and acceptor properties. Thus, we investigated the relationship between the electronic structures of Ru(II) complexes and cytotoxicity by optimizing the electron-withdrawing (complex 1), electron-neutral (complex 2), and electron-donating (complex 3) ligands through DFT calculations, bioactivities tests, and docking studies. Our results indicated that it was not sufficient to consider only either the effect of electron-withdrawing or electron-donating effects on biological activities instead of the total electronic effects. Furthermore, these complexes with electron-donating substituents (complex 3) featured unique "off-on" luminescent emission phenomena caused by the various "HOMO-LUMO" distributions when they interacted with DNA, while complex with electron-withdrawing substituent showed an "always-on" signature. These findings offer valuable insight into the development of bifunctional chemotherapeutic agents along with bioimaging ability.


Assuntos
Complexos de Coordenação , Rutênio , Rutênio/química , Piridinas/química , DNA/química , Teoria da Densidade Funcional , Complexos de Coordenação/farmacologia , Complexos de Coordenação/química
14.
J Supercomput ; : 1-25, 2023 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-37359339

RESUMO

As a popular platform-independent language, Java is widely used in enterprise applications. In the past few years, language vulnerabilities exploited by Java malware have become increasingly prevalent, which cause threats for multi-platform. Security researchers continuously propose various approaches for fighting against Java malware programs. The low code path coverage and poor execution efficiency of dynamic analysis limit the large-scale application of dynamic Java malware detection methods. Therefore, researchers turn to extracting abundant static features to implement efficient malware detection. In this paper, we explore the direction of capturing malware semantic information by using graph learning algorithms and present BejaGNN (Behavior-based Java malware detection via Graph Neural Network), a novel behavior-based Java malware detection method using static analysis, word embedding technique, and graph neural network. Specifically, BejaGNN leverages static analysis techniques to extract ICFGs (Inter-procedural Control Flow Graph) from Java program files and then prunes these ICFGs to remove noisy instructions. Then, word embedding techniques are adopted to learn semantic representations for Java bytecode instructions. Finally, BejaGNN builds a graph neural network classifier to determine the maliciousness of Java programs. Experimental results on a public Java bytecode benchmark demonstrate that BejaGNN achieves high F1 98.8% and is superior to existing Java malware detection approaches, which verifies the promise of graph neural network in Java malware detection.

15.
Adv Sci (Weinh) ; 10(24): e2300791, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37340871

RESUMO

Neuromorphic artificial intelligence systems are the future of ultrahigh performance computing clusters to overcome complex scientific and economical challenges. Despite their importance, the advancement in quantum neuromorphic systems is slow without specific device design. To elucidate biomimicking mammalian brain synapses, a new class of quantum topological neuristors (QTN) with ultralow energy consumption (pJ) and higher switching speed (µs) is introduced. Bioinspired neural network characteristics of QTNs are the effects of edge state transport and tunable energy gap in the quantum topological insulator (QTI) materials. With augmented device and QTI material design, top notch neuromorphic behavior with effective learning-relearning-forgetting stages is demonstrated. Critically, to emulate the real-time neuromorphic efficiency, training of the QTNs is demonstrated with simple hand gesture game by interfacing them with artificial neural networks to perform decision-making operations. Strategically, the QTNs prove the possession of incomparable potential to realize next-gen neuromorphic computing for the development of intelligent machines and humanoids.

16.
Science ; 380(6650): 1179-1184, 2023 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-37228220

RESUMO

The deconfined quantum critical point (DQCP) represents a paradigm shift in quantum matter studies, presenting a "beyond Landau" scenario for order-order transitions. Its experimental realization, however, has remained elusive. Using high-pressure 11B nuclear magnetic resonance measurements on the quantum magnet SrCu2(BO3)2, we here demonstrate a magnetic field-induced plaquette singlet to antiferromagnetic transition above 1.8 gigapascals at a notably low temperature, Tc ≃ 0.07 kelvin. First-order signatures of the transition weaken with increasing pressure, and we observe quantum critical scaling at the highest pressure, 2.4 gigapascals. Supported by model calculations, we suggest that these observations can be explained by a proximate DQCP inducing critical quantum fluctuations and emergent O(3) symmetry of the order parameters. Our findings offer a concrete experimental platform for investigation of the DQCP.

17.
Opt Express ; 31(2): 1079-1091, 2023 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-36785150

RESUMO

We present an implantable metaverse featuring retinal prostheses in association with bionic vision processing. Unlike conventional retinal prostheses, whose electrodes are spaced equidistantly, our solution is to rearrange the electrodes to match the distribution of ganglion cells. To naturally imitate the human vision, a scheme of bionic vision processing is developed. On top of a three-dimensional eye model, our bionic vision processing is able to visualize the monocular image, binocular image fusion, and parallax-induced depth map.


Assuntos
Próteses Visuais , Humanos , Biônica , Percepção Visual , Visão Ocular , Eletrodos
18.
Acta Biomater ; 158: 747-758, 2023 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-36638940

RESUMO

Living organisms are far superior to state-of-the-art devices in visual perception as they have evolved a wide number of capabilities that encompass our most advanced technologies. By leveraging the performance of living organisms and directly interfacing them with artificial components, it can use the intricacy and metabolic efficiency of biological visual sensing within artificial machines. Inspired by the molecular basis (transient receptor potential, TRP) for infrared detection of pit-bearing organisms, we propose a TRP-like biohybrid sensor by integrating upconversion nanoparticles (UCNP) and optogenetically engineered cells on a graphene transistor for infrared sensing and imaging. The UCNP converts infrared light irradiation into blue light, the blue light activates the cells expressed with channelrhodopsin-2 (ChR2) and induces transmembrane photocurrent, and the photocurrent is detected by a biocompatible graphene transistor. Stepwise and overall experimental results show that, upon infrared light irradiation, the UCNP can rapidly mediate cellular photocurrents, which further translates into the extra output current of the graphene transistor. More notably, the response speed of the biohybrid sensor is 1∼3 orders of magnitude faster than those of TRPs heterologously expressed in cell lines in the literature, which confirms the response time advantage of the combination of UCNP and ChR2 within the sensor in place of TRPs. The biohybrid sensor can successfully image infrared targets, proving the feasibility of developing bionic infrared sensing devices by biohybrid integration of nonliving nanomaterials and biological components. This work opens up an avenue for biohybrid sensors to develop the bionic infrared vision that promisingly reproduces the functional superiority of natural organisms. STATEMENT OF SIGNIFICANCE: Infrared sensing and imaging have a wide range of military and civilian applications. Organisms have evolved excellent infrared vision with the molecular basis, transient receptor potential (TRP), and the performance is superior to existing state-of-the-art infrared devices. Inspired by this, a TRP-like biohybrid sensor based on upconversion optogenetics and a 2D material-based device is developed for infrared sensing and imaging. The biohybrid sensor has a relatively fast response speed that is 1∼3 orders of magnitude faster than that of the heterologously expressed TRPs, which enables its capability of infrared imaging with a single pixel-based method. This work broadens the spectrum of biohybrid sensing based on engineered cells to infrared, advancing the process of reproducing the excellent infrared detection of organisms.


Assuntos
Grafite , Nanopartículas , Nanoestruturas , Optogenética/métodos , Raios Infravermelhos
19.
Biomed Mater ; 18(1)2022 12 08.
Artigo em Inglês | MEDLINE | ID: mdl-36541466

RESUMO

Neural networks have been culturedin vitroto investigate brain functions and diseases, clinical treatments for brain damage, and device development. However, it remains challenging to form complex neural network structures with desired orientations and connectionsin vitro. Here, we introduce a dynamic strategy by using diphenylalanine (FF) nanotubes for controlling physical patterns on a substrate to regulate neurite-growth orientation in cultivating neural networks. Parallel FF nanotube patterns guide neurons to develop neurites through the unidirectional FF nanotubes while restricting their polarization direction. Subsequently, the FF nanotubes disassemble and the restriction of neurites disappear, and secondary neurite development of the neural network occurs in other direction. Experiments were conducted that use the hippocampal neurons, and the results demonstrated that the cultured neural networks by using the proposed dynamic approach can form a significant cross-connected structure with substantially more lateral neural connections than static substrates. The proposed dynamic approach for neurite outgrowing enables the construction of oriented innervation and cross-connected neural networksin vitroand may explore the way for the bio-fabrication of highly complex structures in tissue engineering.


Assuntos
Nanotubos , Neuritos , Neuritos/fisiologia , Neurônios , Crescimento Neuronal , Células Cultivadas
20.
Ying Yong Sheng Tai Xue Bao ; 33(11): 2987-2996, 2022 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-36384833

RESUMO

We measured the morphological index, nutritional composition and the expression analysis of key genes during grain development of Paeonia suffruticosa cv. 'Fengdan' grown at altitudes of 100, 650 and 1010 m in Luo-yang. The aim of this study was to examine differences in grain yield traits and the transformation of soluble sugar, starch, soluble protein and fatty acid contents, as well as the related enzyme activity and differential expression of key genes in oil metabolism. The results showed that grain yield traits increased with altitudes and that the growth period of grain at the higher altitudes was longer than that at low and mid altitudes. The soluble sugar and starch in mature grains increased with altitudes, while soluble protein and crude fat did not change. During grain development, the activities of sucrose synthase (SS) and sucrose phosphate synthase (SPS) first decreased and then increased, with the lowest occurred at 90 d after flowering. The activities of pyruvate dehydrogenase (PDH), glutamic-pyruvic transaminase (GPT) and glutamic-oxalacetic transaminease (GOT) increased rapidly during 50-90 d after flowering and peaked at 90 d. The relative expression of acetyl-CoA carboxylase (ACCase) and stearoyl-ACP desaturase (SAD) peaked at 50 d after flowering, and ω-6 fatty acid desaturase 2 (FAD2) peaked at 90 d, in oil tree peony grain at different altitudes. There was a negative correlation of soluble sugar and starch with the accumulation of soluble protein and crude fat. SPS activity was positively correlated with the contents of soluble sugar and starch, and negatively correlated with the contents of soluble protein and crude fat during grain development. Activities of GPT and GOT were negatively associated with the content of soluble sugar and the content of starch, and had a highly significant positive correlation with the contents of soluble protein and crude fat. Activity of PDH was positively correlated with the content of soluble proteins and activities of GPT and GOT, and negatively correlated with the contents of soluble sugar and starch. It suggested that nutrient accumulation in the process of grain development of tree peony was transformed from sugar to crude fat and protein, and that metabolic enzymes, such as SPS, PDH, GPT and GOT, played an important role in this process. Palmitate acid, stearic acid and linoleic acid were negatively correlated with the relative increment of α-linolenic acid, indicating that fatty acid desaturation process in the grain development of tree peony was towards the direction of α-linolenic acid synthesis. The relative expression of ACCase, SAD, and FAD2 was positively correlated with the relative increment of α-linolenic acid accumulation, which played an important role in α-linolenic acid synthesis. The oil quality of tree peony grain was relatively stable at different altitudes, but grain production increased with altitude. Planting oil tree peony at mid to high altitudes could be an important strategy for the efficient use of marginal land in Luoyang.


Assuntos
Paeonia , Paeonia/genética , Paeonia/metabolismo , Altitude , Ácido alfa-Linolênico , Grão Comestível/metabolismo , Amido/metabolismo , Açúcares
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