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2.
Adv Mater ; : e2313511, 2024 Apr 10.
Article in English | MEDLINE | ID: mdl-38597395

ABSTRACT

Moiré superlattices, consisting of rotationally aligned 2D atomically thin layers, provide a highly novel platform for the study of correlated quantum phenomena. However, reliable and efficient construction of moiré superlattices is challenging because of difficulties to accurately angle-align small exfoliated 2D layers and the need to shun wet-transfer processes. Here, efficient and precise construction of various moiré superlattices is demonstrated by picking up and stacking large-area 2D mono- or few-layer crystals with predetermined crystal axes, made possible by a gold-template-assisted mechanical exfoliation method. The exfoliated 2D layers are semiconductors, superconductors, or magnets and their high quality is confirmed by photoluminescence and Raman spectra and by electrical transport measurements of fabricated field-effect transistors and Hall devices. Twisted homobilayers with angle-twisting accuracy of ≈0.3°, twisted heterobilayers with sub-degree angle-alignment accuracy, and multilayer superlattices are precisely constructed and characterized by their moiré patterns, interlayer excitons, and second harmonic generation. The present study paves the way for exploring emergent phenomena in moiré superlattices.

3.
Bioact Mater ; 37: 191-205, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38549775

ABSTRACT

Gene therapy is capable of efficiently regulating the expression of abnormal genes in diseased tissues and expected to be a therapeutic option for refractory diseases. However, unidirectional targeting gene therapy is always desired at the tissue interface. In this study, inspired by the principle that like charges repulse each other, a positively charged micro-nano electrospun fibrous membrane with dual-layer structure was developed by electrospinning technology to achieve unidirectional delivery of siRNA-loaded cationic nanocarriers, thus realizing unidirectional gene therapy at the tendon-paratenon interface. Under the charge repulsion of positively charged layer, more cationic COX-2 siRNA nanocarriers were enriched in peritendinous tissue, which not only improved the bioavailability of the gene drug to prevent the peritendinous adhesion formation, but also avoided adverse effects on the fragile endogenous healing of tendon itself. In summary, this study provides an innovative strategy for unidirectional targeting gene therapy of tissue interface diseases by utilizing charge repulsion to facilitate unidirectional delivery of gene drugs.

4.
Nat Commun ; 15(1): 2724, 2024 Mar 29.
Article in English | MEDLINE | ID: mdl-38553435

ABSTRACT

The applications of self-assembled InAs/GaAs quantum dots (QDs) for lasers and single photon sources strongly rely on their density and quality. Establishing the process parameters in molecular beam epitaxy (MBE) for a specific density of QDs is a multidimensional optimization challenge, usually addressed through time-consuming and iterative trial-and-error. Here, we report a real-time feedback control method to realize the growth of QDs with arbitrary density, which is fully automated and intelligent. We develop a machine learning (ML) model named 3D ResNet 50 trained using reflection high-energy electron diffraction (RHEED) videos as input instead of static images and providing real-time feedback on surface morphologies for process control. As a result, we demonstrate that ML from previous growth could predict the post-growth density of QDs, by successfully tuning the QD densities in near-real time from 1.5 × 1010 cm-2 down to 3.8 × 108 cm-2 or up to 1.4 × 1011 cm-2. Compared to traditional methods, our approach can dramatically expedite the optimization process and improve the reproducibility of MBE. The concepts and methodologies proved feasible in this work are promising to be applied to a variety of material growth processes, which will revolutionize semiconductor manufacturing for optoelectronic and microelectronic industries.

5.
Med Image Anal ; 94: 103122, 2024 May.
Article in English | MEDLINE | ID: mdl-38428270

ABSTRACT

Cortical surface registration plays a crucial role in aligning cortical functional and anatomical features across individuals. However, conventional registration algorithms are computationally inefficient. Recently, learning-based registration algorithms have emerged as a promising solution, significantly improving processing efficiency. Nonetheless, there remains a gap in the development of a learning-based method that exceeds the state-of-the-art conventional methods simultaneously in computational efficiency, registration accuracy, and distortion control, despite the theoretically greater representational capabilities of deep learning approaches. To address the challenge, we present SUGAR, a unified unsupervised deep-learning framework for both rigid and non-rigid registration. SUGAR incorporates a U-Net-based spherical graph attention network and leverages the Euler angle representation for deformation. In addition to the similarity loss, we introduce fold and multiple distortion losses to preserve topology and minimize various types of distortions. Furthermore, we propose a data augmentation strategy specifically tailored for spherical surface registration to enhance the registration performance. Through extensive evaluation involving over 10,000 scans from 7 diverse datasets, we showed that our framework exhibits comparable or superior registration performance in accuracy, distortion, and test-retest reliability compared to conventional and learning-based methods. Additionally, SUGAR achieves remarkable sub-second processing times, offering a notable speed-up of approximately 12,000 times in registering 9,000 subjects from the UK Biobank dataset in just 32 min. This combination of high registration performance and accelerated processing time may greatly benefit large-scale neuroimaging studies.


Subject(s)
Image Processing, Computer-Assisted , Neuroimaging , Humans , Image Processing, Computer-Assisted/methods , Reproducibility of Results , Neuroimaging/methods , Algorithms
6.
Adv Mater ; 36(19): e2311964, 2024 May.
Article in English | MEDLINE | ID: mdl-38302097

ABSTRACT

CRISPR-Cas13 holds substantial promise for tissue repair through its RNA editing capabilities and swift catabolism. However, conventional delivery methods fall short in addressing the heightened inflammatory response orchestrated by macrophages during the acute stages of tendon injury. In this investigation, macrophage-targeting cationic polymers are systematically screened to facilitate the entry of Cas13 ribonucleic-protein complex (Cas13 RNP) into macrophages. Notably, SPP1 (OPN encoding)-producing macrophages are recognized as a profibrotic subtype that emerges during the inflammatory stage. By employing ROS-responsive release mechanisms tailored for macrophage-targeted Cas13 RNP editing systems, the overactivation of SPP1 is curbed in the face of an acute immune microenvironment. Upon encapsulating this composite membrane around the tendon injury site, the macrophage-targeted Cas13 RNP effectively curtails the emergence of injury-induced SPP1-producing macrophages in the acute phase, leading to diminished fibroblast activation and mitigated peritendinous adhesion. Consequently, this study furnishes a swift RNA editing strategy for macrophages in the inflammatory phase triggered by ROS in tendon injury, along with a pioneering macrophage-targeted carrier proficient in delivering Cas13 into macrophages efficiently.


Subject(s)
CRISPR-Cas Systems , Macrophages , Tendon Injuries , Macrophages/metabolism , Animals , Mice , Tendon Injuries/therapy , Tendon Injuries/genetics , Immunotherapy , RNA Editing , RNA, Messenger/genetics , RNA, Messenger/metabolism , RAW 264.7 Cells , Osteopontin/genetics , Osteopontin/metabolism , Reactive Oxygen Species/metabolism
7.
Opt Express ; 32(3): 4457-4472, 2024 Jan 29.
Article in English | MEDLINE | ID: mdl-38297647

ABSTRACT

Terahertz spectrum is easily interfered by system noise and water-vapor absorption. In order to obtain high quality spectrum and better prediction accuracy in qualitative and quantitative analysis model, different wavelet basis functions and levels of decompositions are employed to perform denoising processing. In this study, the terahertz spectra of wheat samples are denoised using wavelet transform. The compound evaluation indicators (T) are used for systematically analyzing the quality effect of wavelet transform in terahertz spectrum preprocessing. By comparing the optimal denoising effects of different wavelet families, the wavelets of coiflets and symlets are more suitable for terahertz spectrum denoising processing than the wavelets of fejer-korovkin and daubechies, and the performance of symlets 8 wavelet basis function with 4-level decomposition is the optimum. The results show that the proposed method can select the optimal wavelet basis function and decomposition level of wavelet denoising processing in the field of terahertz spectrum analysis.

8.
Int J Med Sci ; 21(3): 474-482, 2024.
Article in English | MEDLINE | ID: mdl-38250608

ABSTRACT

Background: The single nucleotide polymorphism (SNP) of Gastrokine-1 (GKN1) is associated with lung cancer but its association with prognosis is not clear. Methods: Genomic DNA was extracted from the blood samples of 888 patients with lung cancer. The association between GKN1 polymorphism rs4254535 and prognostic was analyzed by the Kaplan-Meier (KM) method, Log-rank test, and Cox proportional hazards model. Results: In females and patients diagnosed with late-stage lung cancer, the CC genotype (CC vs TT, adjusted odds ratio [HR] = 0.57, 95% Confidence Interval [CI]: 0.33-0.99, P = 0.045; HR = 0.66, 95% CI: 0.48-0.92, P = 0.014) and recessive CC genotype (CC vs TT + TC, HR = 0.55, 95% CI: 0.32-0.94, P = 0.028; HR = 0.64, 95% CI: 0.47-0.89, P = 0.006) of rs4254535 conferred a better prognosis, compared with the TT and TT + TC genotype. Rs4254535 dominate TC + CC genotype, recessive CC genotype, and C allele who were adenocarcinoma patients had a significantly better prognosis. The recessive CC genotype of non-smoking patients has a better prognosis, compared to the TT + TC genotype. Additionally, in the dominant TT + TC genotype and C allele, no family history patients had a significantly better prognosis, compared to the TT genotype. Conclusion: For lung cancer patients, GKN1 polymorphism rs4254535 may be a protective genetic marker and predicts the prognosis of lung cancer patients.


Subject(s)
Lung Neoplasms , Peptide Hormones , Female , Humans , Prognosis , Lung Neoplasms/genetics , Genotype , Polymorphism, Single Nucleotide/genetics , China
9.
bioRxiv ; 2024 Jan 19.
Article in English | MEDLINE | ID: mdl-38293057

ABSTRACT

The transcription factor BCL11A is a critical regulator of the switch from fetal hemoglobin (HbF: α 2 γ 2 ) to adult hemoglobin (HbA: α 2 ß 2 ) during development. BCL11A binds at a cognate recognition site (TGACCA) in the γ-globin gene promoter and represses its expression. DNA-binding is mediated by a triple zinc finger domain, designated ZnF456. Here, we report comprehensive investigation of ZnF456, leveraging X-ray crystallography and NMR to determine the structures in both the presence and absence of DNA. We delve into the dynamics and mode of interaction with DNA. Moreover, we discovered that the last zinc finger of BCL11A (ZnF6) plays a special role in DNA binding and γ-globin gene repression. Our findings help account for some rare γ-globin gene promoter mutations that perturb BCL11A binding and lead to increased HbF in adults (hereditary persistence of fetal hemoglobin). Comprehending the DNA binding mechanism of BCL11A opens avenues for the strategic, structure-based design of novel therapeutics targeting sickle cell disease and ß-thalassemia.

10.
J Ethnopharmacol ; 322: 117657, 2024 Mar 25.
Article in English | MEDLINE | ID: mdl-38145861

ABSTRACT

ETHNOPHARMACOLOGICAL RELEVANCE: Danlou tablet (DLT) is a traditional Chinese medicinal formulation known for replenishing Qi, promoting blood circulation, and resolving stasis. Its pharmacological actions primarily involve anti-inflammatory, antioxidant stress reduction, antiapoptotic, proangiogenic, and improved energy metabolism. DLT has been confirmed to have favorable therapeutic effects on ischemic stroke (IS). However, the underlying mechanism through which DLT affects IS-induced brain injury remains unknown. AIM OF THE STUDY: This study aims to investigate the effects and underlying mechanisms of danlou tablet on ischemic stroke based on network pharmacology and experimental verification. MATERIALS AND METHODS: Using a transient middle cerebral artery occlusion (tMCAO) mouse model, the impact of DLT on the blood‒brain barrier (BBB) and brain injury in mice was assessed. Network pharmacology and bioinformatics analyses were utilized to explore the potential mechanisms of DLT in treating IS. Endothelial cells were cultured to observe the effects of DLT on vascular endothelial cells after oxygen-glucose deprivation/reperfusion, and these findings were validated in the brains of tMCAO mice. RESULTS: DLT alleviated oxidative stress and brain damage in tMCAO mice, mitigating BBB damage. A total of 185 potential targets through which DLT regulates IS were identified, including COX2, a known critical marker of ferroptosis, which identified as a key target. In vitro and in vivo experiments demonstrated that DLT significantly (p < 0.05) improved cell death and vascular barrier damage in IS, reducing intracellular oxidative stress and COX2 protein levels while increasing SLC7A11 and GPX4 protein levels. CONCLUSIONS: This study demonstrated that DLT maintained BBB integrity and alleviated brain injury of tMCAO mice by inhibiting ferroptosis. The study partially unraveled the mechanism through which DLT functioned in treating IS and further clarified the pivotal active components of DLT, thereby providing a theoretical scientific basis for treating IS with DLT.


Subject(s)
Brain Injuries , Brain Ischemia , Drugs, Chinese Herbal , Ferroptosis , Ischemic Stroke , Reperfusion Injury , Stroke , Mice , Animals , Blood-Brain Barrier , Ischemic Stroke/metabolism , Brain Ischemia/drug therapy , Brain Ischemia/metabolism , Cyclooxygenase 2/metabolism , Endothelial Cells/metabolism , Infarction, Middle Cerebral Artery/drug therapy , Infarction, Middle Cerebral Artery/metabolism , Brain Injuries/metabolism , Reperfusion Injury/drug therapy , Stroke/drug therapy , Stroke/metabolism
11.
Article in English | MEDLINE | ID: mdl-38060359

ABSTRACT

In the design of prosthetic hand fingers, achieving human-like movement while meeting anthropomorphic demands such as appearance, size, and lightweight is quite challenging. Human finger movement involves two distinct motion characters during natural reach-and-grasp tasks: consistency in the reaching stage and adaptability in the grasping stage. The former one enhances grasp stability and reduces control complexity; the latter one promotes the adaptability of finger to various objects. However, conventional tendon-driven prosthetic finger designs typically incorporate bulky actuation modules or complex tendon routes to reconcile the consistency and adaptability. In contrast, we propose a novel friction clutch consisting of a single tendon and slider, which is simple and compact enough to be configurated within the metacarpal bone. Through tactfully exploiting the friction force to balance the gravity effect on each phalanx during finger motion, this design effectively combines both consistency and adaptability. As a result, the prosthetic finger can maintain consistent motion unaffected by any spatial posture during reaching, execute adaptive motion during grasping, and automatically switch between them, resulting in human-like reach-and-grasp movements. Additionally, the proposed finger achieves a highly anthropomorphic design, weighing only 18.9 g and possessing the same size as an adult's middle finger. Finally, a series of experiments validate the theoretical effectiveness and motion performance of the proposed design. Remarkably, the mechanical principle of the proposed friction clutch is beneficial to achieve highly anthropomorphic design, providing not only a new strategy to prosthetic hand design but also great potential in hand rehabilitation.


Subject(s)
Fingers , Hand , Adult , Humans , Friction , Movement , Hand Strength
12.
Materials (Basel) ; 16(19)2023 Sep 28.
Article in English | MEDLINE | ID: mdl-37834584

ABSTRACT

Many bridge structural components are subjected to repetitive vehicle load and temperature gradient action. The resulting cyclic tensile stresses within the structures could cause premature fatigue failure of concrete, dramatically impairing structural components' durability and sustainability. Although substantial knowledge of fatigue properties on low-strength pavement concrete and high-strength structural concrete has been obtained, research on the most widely used normal-grade ordinary concrete in bridge engineering is still ongoing. Therefore, a four-point bending fatigue test of 97 C50 concrete specimens under a constant amplitude sinusoidal wave was conducted in the laboratory, the flexural fatigue behavior of plain and reinforced concrete specimens was studied, and the cyclic deformation evolution of concrete under fatigue loading was obtained. The empirical fatigue S-N equations of concrete with a failure probability p of 0.1~0.5 were derived through statistical analysis of the test results. The fatigue life of the tested specimens exhibited a two-parameter Weibull distribution. In addition to the maximum stress level Smax, the stress ratio R is also a key factor affecting the flexural fatigue life of concrete N. The semi-logarithmic and logarithmic equations were almost identical at the tested stress levels, the latter predicting longer fatigue life for Smax < 0.70. The restraining effect from steel reinforcement slightly lengthened the concrete's fatigue cracking initiation life. The insight into concrete flexural fatigue properties from this study not only contributes to a better understanding of structural concrete, but also provides a basis for the practical evaluation of concrete or composite bridge decks.

13.
Foods ; 12(17)2023 Aug 28.
Article in English | MEDLINE | ID: mdl-37685168

ABSTRACT

The structure of the grain-and-oil-food-supply chain has the characteristics of complexity, cross-regionality, a long cycle, and numerous participants, making it difficult to maintain the safety of supply. In recent years, some phenomena have emerged in the field of grain procurement and sale, such as topping the new with the old, rotating grains, the pressure of grades and prices, and counterfeit oil food, which have seriously threatened grain-and-oil-food security. Blockchain technology has the advantage of decentralization and non-tampering Therefore, this study analyzes the characteristics of traceability data in the grain-and-oil-food-supply chain, and presents a blockchain-based traceability model for the grain-and-oil-food-supply chain. Firstly, a new method combining blockchain and machine learning is proposed to enhance the authenticity and reliability of blockchain source data by constructing anomalous data-processing models. In addition, a lightweight blockchain-storage method and a data-recovery mechanism are proposed to reduce the pressure on supply-chain-data storage and improve fault tolerance. The results indicate that the average query delay of public data is 0.42 s, the average query delay of private data is 0.88 s, and the average data-recovery delay is 1.2 s. Finally, a blockchain-based grain-and-oil-food-supply-chain traceability system is designed and built using Hyperledger Fabric. Compared with the existing grain-and-oil-food-supply chain, the model constructed achieves multi-source heterogeneous data uploading, lightweight storage, data recovery, and traceability in the supply chain, which are of great significance for ensuring the safety of grain-and-oil food in China.

14.
Plant Dis ; 2023 Sep 12.
Article in English | MEDLINE | ID: mdl-37700473

ABSTRACT

Dioscorea polystachya (Chinese yam) is a kind of medicine and food homologous crop, the tubers as its main production organ, with high potassium, low fiber, high protein and rich nutrition characteristics. In 2022, at the Chinese herbal medicine planting experimental site in Anguo, Baoding City, Hebei Province, China, we found the symptoms of Chinese yam decay during the storage, with an incidence of 15%~25%. The diseased part of Chinese yam tuber rots expands from the outside to the inside and sags, with a brown or dark brown discoloration, and the surface covered with a thick grayish green mold. The diseased tissue was first rinsed with clean water to remove dirts from the surface. Thereafter, 3 to 4 mm Chinese yam pieces were picked from rotting edge with a sterilized forceps, sterilized with 75% alcohol for 30 s followed by 0.1% mercuric chloride solution for 1min, and then rinsed three times with sterile water. The sterilized pieces were cultured on potato dextrose agar (PDA). One isolated fungus was obtained, and conidia were observed after incubation for 5 days at 26°C. Pure cultures were isolated by single-spore isolation. Conidia were single spore, round or oval, colorless. Conidiophores produce several rounds of symmetric or asymmetric small stems after multiple branches, which were shaped like brooms. The length and width of 100 conidia were measured, and size ranged from 3 to 4×3 to 4 µm. On the basis of morphological characteristics, the isolate was identified as Penicillium spp. (Uy et al. 2022). To further assess the identity of isolated species, the genomic DNA of the fungal isolate (SYRF1) was extracted by CTAB protocol. The ribosomal DNA internal transcribed spacer (ITS) region and the ribosomal large subunit (LSU) were amplified and sequenced with primers ITS1/4, LR5/LROR respectively (White et al. 1990, Xu et al. 2010). The obtained ITS-rDNA region and LSU sequences (GenBank accession OQ707937 and OQ704185) of the isolate were more than 99% identity to the corresponding sequences of Penicillium cellarum in GenBank (KM249068 and MG714818). Phylogenetic results based on a maximum-likelihood analysis revealed that SYRF1 was grouped with P. cellarum. To determine the pathogenicity of the isolated fungi, tests were carried out by aseptic inoculation of fresh and healthy tubers. Before the experiment, the healthy tubers were washed, surface disinfected and dried. The tubers were then wounded with sterile inoculation needles, and the conidium-bearing hyphal discs (5 mm) were inoculated on the surface of the wounded tubers and covered with wet sterile cotton. Three tubers were inoculated repeatedly each time as the experimental group. Inoculate sterile PDA with three tubers as the control group. Each tuber was inoculated with four mycelium disks, and the pathogenicity test was repeated four times. The inoculated tubers were incubated at 26°C for 14 days with sterile PDA as control. After ten days, the inoculated points showed symptoms similar to those of the initial infection, whereas controls remained symptomless. The reisolated fungus matched SYRF1 based on morphological and sequence analyses, thereby fulfilling Koch's postulates. To the best of our knowledge, this is the first report of Penicillium cellarum as causative agent of postharvest rot of Chinese yam tubers in China. This finding will help inform the prevention and management of postharvest diseases of Chinese yam tubers.

15.
Int J Mol Sci ; 24(13)2023 Jun 30.
Article in English | MEDLINE | ID: mdl-37446112

ABSTRACT

The frequency range of terahertz waves (THz waves) is between 0.1 and 10 THz and they have properties such as low energy, penetration, transients, and spectral fingerprints, which are especially sensitive to water. Terahertz, as a frontier technology, have great potential in interpreting the structure of water molecules and detecting biological water conditions, and the use of terahertz technology for water detection is currently frontier research, which is of great significance. Firstly, this paper introduces the theory of terahertz technology and summarizes the current terahertz systems used for water detection. Secondly, an overview of theoretical approaches, such as the relaxation model and effective medium theory related to water detection, the relationship between water molecular networks and terahertz spectra, and the research progress of the terahertz detection of water content and water distribution visualization, are elaborated. Finally, the challenge and outlook of applications related to the terahertz wave detection of water are discussed. The purpose of this paper is to explore the research domains on water and its related applications using terahertz technology, as well as provide a reference for innovative applications of terahertz technology in moisture detection.


Subject(s)
Technology , Water , Water/chemistry
16.
Neoplasma ; 70(3): 443-450, 2023 Jun.
Article in English | MEDLINE | ID: mdl-37498067

ABSTRACT

The 5-year survival rate for patients with lung cancer, the world's second most frequent malignant tumor, is less than 20%, and its prognosis cannot be clearly predicted. Our aim was to analyze the epidermal growth factor receptor (EGFR) rs763317 (G>A) single nucleotide polymorphism and its association with prognosis in Chinese Han lung cancer patients. 839 patients with primary lung cancer were recruited, and genomic DNA was extracted and genotyped by SNPscan. Kaplan-Meier technique and multivariate Cox proportional hazards model were used to analyze the association between prognosis and EGFR polymorphism rs763317. A significant association after stratification by age, significantly increased lung cancer risk was associated with the AA homozygous genotype of rs763317 (adjusted hazard ratio = 2.53, 95% CI: 1.31-4.88, p=0.005), and conferred a poor survival for lung cancer patients (MST: median survival time: 13.6 months) compared with GG genotype (MST: 41.5 months), and in the recessive model AA genotype (AA vs. GG + GA; adjusted hazard ratio = 2.57, 95% CI: 1.34-4.93, p=0.004) who were young (<60 years) had a significantly increased risk of death. The EGFR polymorphism rs763617 might serve as a significant genetic marker for predicting the prognosis of lung cancer.


Subject(s)
Carcinoma, Non-Small-Cell Lung , Lung Neoplasms , Humans , Carcinoma, Non-Small-Cell Lung/genetics , East Asian People , ErbB Receptors/genetics , Genetic Predisposition to Disease , Genotype , Lung Neoplasms/genetics , Lung Neoplasms/pathology , Polymorphism, Single Nucleotide , Prognosis
17.
Nanotechnology ; 34(42)2023 Jul 31.
Article in English | MEDLINE | ID: mdl-37437548

ABSTRACT

Considering the advantages of MOF-based, CdSe-based, and rGO-based materials, CdSe nanoparticles encapsulated with rGO (CdSe@rGO) were synthesized by a metal-organic framework derived method. CdSe nanoparticles encapsulated with rGO can effectively tolerate volume expansion and improve electrical conductivity, leading to excellent cycling stability (396 mAh g-1at 0.3 A g-1after 200 cycles, 311 mAh g-1at 0.5 A g-1after 500 cycles), and rate performance (562 mAh g-1at 0.1 A g-1and 122.2 mAh g-1at 4 A g-1) for lithium-ion storage. This strategy for preparing metal selenides protected by carbon layers can be extended to the design of other high-performance materials.

18.
Nano Lett ; 23(12): 5610-5616, 2023 Jun 28.
Article in English | MEDLINE | ID: mdl-37321211

ABSTRACT

Two-dimensional checkerboard lattice, the simplest line-graph lattice, has been intensively studied as a toy model, while material design and synthesis remain elusive. Here, we report theoretical prediction and experimental realization of the checkerboard lattice in monolayer Cu2N. Experimentally, monolayer Cu2N can be realized in the well-known N/Cu(100) and N/Cu(111) systems that were previously mistakenly believed to be insulators. Combined angle-resolved photoemission spectroscopy measurements, first-principles calculations, and tight-binding analysis show that both systems host checkerboard-derived hole pockets near the Fermi level. In addition, monolayer Cu2N has outstanding stability in air and organic solvents, which is crucial for further device applications.

19.
Adv Sci (Weinh) ; 10(19): e2207383, 2023 07.
Article in English | MEDLINE | ID: mdl-37204068

ABSTRACT

Heterotopic ossification (HO) represents an unwanted ossific wound healing response to the soft tissue injury which caused catastrophic limb dysfunction. Recent studies established the involvement of inflammation and cellular senescence in the tissue healing process, though their role in HO still remained to be clarified. Here, a novel crosstalk where the pyroptotic macrophages aroused tendon-derived stem cells (TDSCs) senescence is revealed to encourage osteogenic healing during trauma-induced HO formation. Macrophage pyroptosis blockade reduces the senescent cell burden and HO formation in NLRP3 knockout mice. Pyroptosis-driven IL-1ß and extracellular vesicles (EVs) secretion from macrophages are determined to motivate TDSCs senescence and resultant osteogenesis. Mechanistically, pyroptosis in macrophages enhances the exosomal release of high mobility group protein 1 (HMGB1), which directly bounds TLR9 in TDSCs to trigger morbid signaling. NF-κB signaling is confirmed to be the converging downstream pathway of TDSCs in response to HMGB1-containing EVs and IL-1ß. This study adds insights into aberrant regeneration-based theory for HO formation and boosts therapeutic strategy development.


Subject(s)
HMGB1 Protein , Ossification, Heterotopic , Animals , Mice , Cellular Senescence , HMGB1 Protein/metabolism , Macrophages/metabolism , NLR Family, Pyrin Domain-Containing 3 Protein/metabolism , Ossification, Heterotopic/etiology , Ossification, Heterotopic/metabolism , Wound Healing
20.
Mater Today Bio ; 20: 100649, 2023 Jun.
Article in English | MEDLINE | ID: mdl-37206877

ABSTRACT

Due to local overactive inflammatory response and impaired angiogenesis, current treatments for diabetic wounds remain unsatisfactory. M2 macrophage-derived exosomes (MEs) have shown considerable potential in biomedical applications, especially since they have anti-inflammatory properties that modulate macrophage phenotypes. However, exosome-based strategies still have limitations, such as short half-lives and instability. Herein, we develop a double-layer microneedle-based wound dressing system (MEs@PMN) by encapsulating MEs in the needle tips and polydopamine (PDA) nanoparticles in backing layer to simultaneously suppress inflammation and improve angiogenesis at the wound site. In vitro, released MEs increased macrophage polarization towards the M2 phenotype. In addition, mild heat (40 â€‹°C) generated by the photosensitive PMN backing layer contributed to improved angiogenesis. More importantly, MEs@PMN also showed promising effects in diabetic rats. The uncontrolled inflammatory response at the wound site was inhibited by MEs@PMN during a 14-day period; in addition, MEs and the photothermal effects produced by PMN provided a combined proangiogenic effect by improving the expression of CD31 and vWF. Collectively, this study provides a simple and efficient cell-free strategy for suppressing inflammation and promoting vascular regeneration to treat diabetic wounds.

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