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Microtia is a congenital auricle dysplasia with a high incidence and tissue engineering technology provides a promising strategy to reconstruct auricles. We previously described that the engineered cartilage constructed from microtia chondrocytes exhibited inferior levels of biochemical and biomechanical properties, which was proposed to be resulted of the decreased migration ability of microtia chondrocytes. In the current study, we found that Rho GTPase members were deficient in microtia chondrocytes. By overexpressing RhoA, Rac1, and CDC42, respectively, we further demonstrated that RhoA took great responsibility for the decreased migration ability of microtia chondrocytes. Moreover, we constructed PGA/PLA scaffold-based cartilages to verify the chondrogenic ability of RhoA overexpressed microtia chondrocytes, and the results showed that overexpressing RhoA was of limited help in improving the quality of microtia chondrocyte engineered cartilage. However, coculture of adipose-derived stem cells (ADSCs) significantly improved the biochemical and biomechanical properties of engineered cartilage. Especially, coculture of RhoA overexpressed microtia chondrocytes and ADSCs produced an excellent effect on the wet weight, cartilage-specific extracellular matrix, and biomechanical property of engineered cartilage. Furthermore, we presented that coculture of RhoA overexpressed microtia chondrocytes and ADSCs combined with human ear-shaped PGA/PLA scaffold and titanium alloy stent fabricated by CAD/CAM and 3D printing technology effectively constructed and maintained auricle structure in vivo. Collectively, our results provide evidence for the essential role of RhoA in microtia chondrocytes and a developed strategy for the construction of patient-specific tissue-engineered auricular cartilage.Graphical Abstract

Clamp loaders are AAA+ ATPases that facilitate high-speed DNA replication. In eukaryotic and bacteriophage clamp loaders, ATP hydrolysis requires interactions between aspartate residues in one protomer, present in conserved ‘DEAD-box’ motifs, and arginine residues in adjacent protomers. We show that functional defects resulting from a DEAD-box mutation in the T4 bacteriophage clamp loader can be compensated by widely distributed single mutations in the ATPase domain. Using cryo-EM, we discovered an unsuspected inactive conformation of the clamp loader, in which DNA binding is blocked and the catalytic sites are disassembled. Mutations that restore function map to regions of conformational change upon activation, suggesting that these mutations may increase DNA affinity by altering the energetic balance between inactive and active states. Our results show that there are extensive opportunities for evolution to improve catalytic efficiency when an inactive intermediate is involved.

Despite the progress that has been made in diverse DNA-based nanodevices to in situ monitor the activity of the DNA repair enzymes in living cells, the significance of improving both the sensitivity and specificity has remained largely neglected and understudied. Herein, we propose a regulatable DNA nanodevice to specifically monitor the activity of DNA repair enzymes for early evaluation of cancer mediated by genomic instability. Concretely, an AND logic gate-regulated DNAzyme nanoflower was rationally designed by the self-assembly of the DNA duplex modified with both apurinic/apyrimidinic (AP) site and methyl lesion site. The DNAzyme nanoflower could be reconfigured under the repair of AP sites and O6-methylguanine sites by apurinic/apyrimidinic endonuclease 1 (APE1) and O6-methylguanine methyltransferase (MGMT) to produce a fluorescent signal, realizing the sensitive monitoring of the activity of APE1 and MGMT. Compared to the free DNAzyme duplex, the fluorescent response of the DNAzyme nanoflower increased by 60%, due to the effective enrichment of the DNA probes by the nanoflower structure. More importantly, we have demonstrated that the dual-enzyme activated strategy allows imaging of specific cancer cells in the AND logic gate manner using MCF-7 as a cancer cell model, improving the specificity of cancer cell imaging. This AND logic gate-regulated multifunctional DNAzyme nanoflower provides a simple tool for simultaneously visualizing multiple DNA repair enzymes, holding great potential in early clinical diagnosis and drug discovery.

Atrial fibrillation (AF) is a common cardiac arrhythmia with serious health consequences if not detected and treated early. Detecting AF using wearable devices with photoplethysmography (PPG) sensors and deep neural networks has demonstrated some success using proprietary algorithms in commercial solutions. However, to improve continuous AF detection in ambulatory settings towards a population-wide screening use case, we face several challenges, one of which is the lack of large-scale labeled training data. To address this challenge, we propose to leverage AF alarms from bedside patient monitors to label concurrent PPG signals, resulting in the largest PPG-AF dataset so far (8.5 M 30-second records from 24,100 patients) and demonstrating a practical approach to build large labeled PPG datasets. Furthermore, we recognize that the AF labels thus obtained contain errors because of false AF alarms generated from imperfect built-in algorithms from bedside monitors. Dealing with label noise with unknown distribution characteristics in this case requires advanced algorithms. We, therefore, introduce and open-source a novel loss design, the cluster membership consistency (CMC) loss, to mitigate label errors. By comparing CMC with state-of-the-art methods selected from a noisy label competition, we demonstrate its superiority in handling label noise in PPG data, resilience to poor-quality signals, and computational efficiency.

The effects of impurity, safety factor ( ${q}$ ), and magnetic shear ( $\hat {s}$ ) on kinetic ballooning mode (KBM) in tokamak plasmas, with positive impurity density gradient (for which ${L}_{ez}\equiv {L}_{ne} / {L}_{nz} < 0$ holds, with ${L}_{ne(z)}=-({{d\text {ln}}{n}_{e(z)}} / {dr})^{-1}$ , and here, the electron and ion density gradients being negative are assumed), are numerically studied by means of gyrokinetic simulation, where the concise and efficient gyrokinetic model for KBM, including impurity effect, is employed. The KBM instability with the representative parameter of $0 < \beta ({2}/{3}){\varepsilon }$ ( $\beta \equiv $ the ratio of plasma thermal to magnetic pressures and ${\varepsilon }= {a} / {R}$ with ${a}$ and ${R}$ the minor and major radii of the plasma torus, respectively) is focused on, for which the magnetic compression effect is unnecessary to be considered. The impurity effect on KBM that is always stabilizing for the case ${L}_{ez}>0$ is confirmed first, and then, it is revealed that for the case ${L}_{ez} < 0$ , the dependences of mode growth rate on ion temperature gradient (ITG) ( ${\eta }_{i}$ ) and on impurity charge concentration in high ${q}$ case are opposite to those in low ${q}$ case, owing to the different effects of impurities on KBMs in different regions of safety factor. The mode structure width is varied due to ${q}$ and $\hat {s}$ or the presence of impurities. The most unstable perturbation in ${\beta }$ space has a wider wavenumber spectrum with residual instability. The dependence of the mode growth rate on $\hat {s}$ and ${q}$ is not monotonic. The turning points of $\hat {s}$ and ${q}$ satisfy $\hat {s}_{c}\approx q/2$ and ${q}_{c}\approx 2\hat {s}$ , respectively, while ${\beta }_{e}$ value and impurity ion species, especially with ${L}_{ez} < 0$ , significantly modify the relationships. The reasonability of applying the simplified model to this work and the application prospects of this research are also discussed.

Introduction: Post-operative nausea and/or vomiting (PONV) is a common post-operative adverse reaction and has been associated with post-operative sufentanil injection. The assessment of the relationship between intraoperative opioid consumption and PONV has been understudied. This study examined the relationship between intraoperative sufentanil administration and PONV. Methods: This was a single-center retrospective observational study. Patients who underwent video-assisted thoracoscopic surgery under general anesthesia with the preoperative thoracic paravertebral block between January 2017 and June 2020 at the Peking University People’s Hospital were recruited for this study. Patients were grouped into two groups according to whether or not PONV occurred on postoperative day 1 (POD1). The factors associated with PONV were analyzed using logistic regression. Results: A total of 2733 patients, 1510 males and 1223 females, were included in this study. Among them, 143 patients developed PONV, a 5.2% (143/2733) PONV incidence. Logistic regression analysis showed that female, nonsmoking, sufentanil patient-controlled intravenous analgesia (PCIA), POD1 opioids consumption, and a time-weighted average of intraoperative sufentanil (twSuf) were associated with PONV. All patients were further divided into four subgroups based on intraoperative twSuf. Logistic regression analysis revealed that twSuf higher than 0.21 μg kg–1h–1was an independent risk factor for PONV. Conclusions: Intraoperative sufentanil injection with a twSuf higher than 0.21 μg kg−1h−1increased the risk of PONV in patients undergoing thoracoscopic surgery under general anesthesia after a preoperative thoracic paravertebral block.

Element W can effectively improve the density of energetic structural materials. However, W is an inert element and does not combust in air. To change the reaction characteristics of W, 60 at.% Al was introduced into W through mechanical alloying. XRD analysis shows that after 50 h of ball milling, the diffraction peak of Al completely disappears and W(Al60) super-saturated solid solution powder is obtained. Further observation by HAADF and HRTEM reveals that the W(Al60) super-saturated solid solution powder is a mixture of solid solution and amorphous phase. Based on the good thermal stability of W(Al60) alloy powder below 1000 °C, W(Al60)–Al composite was synthesized by hot pressing process. Impact initiation experiments suggest that the W(Al60)–Al composite has excellent reaction characteristics, and multiple types of tungsten oxides are detected in the reaction products, showing that the modified W is combustible in air. Due to the combustion of tungsten, the energy release rate of the W(Al60)–Al composite at speed of 1362 m/s reaches 2.71 kJ/g.

Graphical abstract:

Plate-based cellular materials exhibit greater stiffness and strength than conventional cellular materials formed by struts. In this study, we designed and fabricated a plate-based auxetic cylinder metamaterial using high-resolution projection micro-stereolithography three-dimensional printing technique. Experiment and modeling results validated the auxetic behavior of the plate-based cylinder. The normalized Young’s modulus and yield strength of a four-layer auxetic cylinder are increased by 141% and 32%, respectively, compared with the conventional auxetic honeycomb. This study presents a universal strategy for fabricating plate-based auxetic metamaterials with appropriate mechanical performance for various structural applications.

PurposeThe goal was to develop a fully automated grading system for the evaluation of punctate epithelial erosions (PEEs) using deep neural networks.MethodsA fully automated system was developed to detect corneal position and grade staining severity given a corneal fluorescein staining image. The fully automated pipeline consists of the following three steps: a corneal segmentation model extracts corneal area; five image patches are cropped from the staining image based on the five subregions of extracted cornea; a staining grading model predicts a score for each image patch from 0 to 3, and automated grading score for the whole cornea is obtained from 0 to 15. Finally, the clinical grading scores annotated by three ophthalmologists were compared with automated grading scores.ResultsFor corneal segmentation, the segmentation model achieved an intersection over union of 0.937. For punctate staining grading, the grading model achieved a classification accuracy of 76.5% and an area under the receiver operating characteristic curve of 0.940 (95% CI 0.932 to 0.949). For the fully automated pipeline, Pearson’s correlation coefficient between the clinical and automated grading scores was 0.908 (p<0.01). Bland-Altman analysis revealed 95% limits of agreement between the clinical and automated grading scores of between −4.125 and 3.720 (concordance correlation coefficient=0.904). The average time required for processing a single stained image during pipeline was 0.58 s.ConclusionA fully automated grading system was developed to evaluate PEEs. The grading results may serve as a reference for ophthalmologists in clinical trials and residency training procedures.

Photoplethysmography (PPG) is a ubiquitous physiological measurement that detects beat-to-beat pulsatile blood volume changes and hence has a potential for monitoring cardiovascular conditions, particularly in ambulatory settings. A PPG dataset that is created for a particular use case is often imbalanced, due to a low prevalence of the pathological condition it targets to predict and the paroxysmal nature of the condition as well. To tackle this problem, we propose log-spectral matching GAN (LSM-GAN), a generative model that can be used as a data augmentation technique to alleviate the class imbalance in a PPG dataset to train a classifier. LSM-GAN utilizes a novel generator that generates a synthetic signal without a up-sampling process of input white noises, as well as adds the mismatch between real and synthetic signals in frequency domain to the conventional adversarial loss. In this study, experiments are designed focusing on examining how the influence of LSM-GAN as a data augmentation technique on one specific classification task - atrial fibrillation (AF) detection using PPG. We show that by taking spectral information into consideration, LSM-GAN as a data augmentation solution can generate more realistic PPG signals.

The study explores the effects of electroacupuncture (EA) at the governing vessel (GV) on proteomic changes in the hippocampus of rats with cognitive impairment.

ABSTRACTThis study aimed to investigate the expression of autophagy-related proteins in a mouse model of neuromyelitis optica (NMO). Mice were assigned to one of four groups: an animal experimental model group (NMO-EAE group, given with exogenous IL-17A), Interleukin-17 monoclonal antibody intervention group (NMO-EAE_0IL17inb), No exogenous interleukin-17 enhanced immune intervention group (NMO-EAE_0IL17), and a control group. Behavioral scores were assessed in each group, and the protein expressions of sequestosome 1 (P62), Beclin-1, the mammalian target of rapamycin (mTOR), phosphoinositide 3-kinase (PI3K-I), and LC3II/LC3I were detected using Western blotting. In the NMO-EAE_0IL17 group, the expression of Beclin-1 decreased, the LC3II/LC3I ratio was lower, and the expressions of P62, mTOR, and PI3K-I increased; after administration of IL-17A inhibitor into the brain tissue, however, the expression of Beclin-1 increased significantly, along with the LC3II/LC3I ratio, while the expressions of P62, mTOR and PI3K-I protein decreased significantly. In terms of behavioral scores, the scores of optic neuritis and myelitis were more serious, onset occurred earlier and the progress was faster, after the administration of IL-17A. In the mechanism of NMO animal model, IL-17A may regulate autophagy and affect the disease process through the activation of the PI3K–mTOR signaling pathway.

DNA methylation predominantly occurs within the CpG dinucleotide, which is the main epigenetic form of gene expression regulation in mammals. Genomic DNA with CpG sites has different sequence lengths and complex secondary structures, resulting in the complexity and diversity of the samples. Therefore, highly efficient quantification of DNA methylation in complex samples remains challenging. Herein, the regulatable DNAzyme motor triggered by strand displacement amplification (SDA) was designed to quantify 5-hydroxymethylcytosine (5hmC) signatures as a model. Briefly, the 5hmC sites as primary target were specifically labeled with DNA primers and converted into a large number of single-stranded DNA (secondary target) viathe SDA reaction which could activate the DNAzyme motor. With the increase of secondary target, the DNAzyme motor gradually recovered its activity and could continuously cleave the track strands labeled quenching probes, causing electrochemiluminescence signal recovery and detection limit down to 0.49 fM for 5hmC. This strategy provides a new route to quantify natural base modifications in DNA and would hold promising potential for the early diagnosis of cancer and other diseases related to 5hmC.

Anaplastic lymphoma kinase (ALK), a receptor tyrosine kinase of the insulin receptor kinase subfamily, is activated in multiple cancer types through translocation or overexpression. Although several generations of ALK tyrosine kinase inhibitors (TKIs) have been developed for clinic use, drug resistance remains a major challenge. In this study, by quantitative proteomic approach, we identified the glycolytic regulatory enzyme, 6-phosphofructo-2-kinase/fructose-2,6-biphosphatase 3 (PFKFB3), as a new target of ALK. Expression of PFKFB3 is highly dependent on ALK activity in ALK+anaplastic large cell lymphoma and non-small-cell lung cancer (NSCLC) cells. Notably, ALK and PFKFB3 expressions exhibit significant correlation in clinic ALK+NSCLC samples. We further demonstrated that ALK promotes PFKFB3 transcription through the downstream transcription factor STAT3. Upregulation of PFKFB3 by ALK is important for high glycolysis level as well as oncogenic activity of ALK+lymphoma cells. Finally, targeting PFKFB3 by its inhibitor can overcome drug resistance in cells bearing TKI-resistant mutants of ALK. Collectively, our studies reveal a novel ALK–STAT3–PFKFB3 axis to promote cell proliferation and tumorigenesis, providing an alternative strategy for the treatment of ALK-positive tumors.

Circular RNAs (circRNAs), emerging as a new type of non‐coding RNAs, play important roles in cancers. Instead, the functions and mechanisms of circ_0011385 in cervical cancer (CC) are still inconclusive. Microarray data GSE102686 was downloaded from Gene Expression Omnibus (GEO) database, and were utilized to screen out circRNAs differently expressed in CC tissues. Circ_0011385, miR‐149‐5p, SRY‐box transcription factor 4 (SOX4) mRNA expressions in CC tissues and cells were probed by quantitative real‐time PCR (qRT‐PCR). CC cell lines with circ_0011385 knockdown were constructed, and he multiplication, migration, invasion, and apoptosis of CC cells were evaluated by cell counting kit‐8 (CCK‐8) method, transwell assay, and flow cytometry. In addition, the targeting relationships between miR‐149‐5p and circ_0011385 or SOX4 mRNA 3′UTR were probed by dual‐luciferase reporter gene assay and RNA pull‐down assay. The regulatory function of circ_0011385 and miR‐149‐5p on SOX4 expression was studied with western blot. Expressions of circ_0011385 and SOX4 mRNA were raised in CC tissues and cells, while miR‐149‐5p expression was decreased. Knocking down circ_0011385 restrained the multiplication, migration, and invasion of CC cells and induced the apoptosis. Circ_0011385 directly targeted miR‐149‐5p, and SOX4 was the target of miR‐149‐5p, which could be positively regulated by circ_0011385. Circ_0011385 elevates SOX4 expression by targeting miR‐149‐5p, thus participating in promoting the malignant biological behaviors of CC cells.

The microstructure, mechanical properties and flame resistance behavior of the AZ91−1Ce alloys with different Ca additions were firstly investigated. Then, the effect of processing parameters, including applied pressures and rotation speeds, on the microstructure and mechanical properties of the rheo-squeeze casting AZ91−1Ce−2Ca alloy was studied. The results indicate that with the increase of Ca content, the microstructure is refined and the flame resistance of the AZ91−1Ce−xCa alloys increases. But when the Ca content exceeds 1 wt.%, with the Ca content increasing, the mechanical properties of the AZ91−1Ce−xCa alloys reduce rapidly. For rheo-squeeze casting process, the increase of applied pressure and rotation speed can both bring about significant refinement in the microstructure of the AZ91−1Ce−2Ca alloy and reduction of the porosity, so the mechanical properties increase. Compared to conventional casting, the AZ91−1Ce alloy with the addition of 2 wt.% Ca by rheo-squeeze casting not only guarantees the oxidation resistance (801 °C), but also improves mechanical properties.

Autologous bone marrow mononuclear cell (BMMNC) transplantation has been widely studied in recent years. The fresh cell cocktail in BMMNCs, without going through the in vitro culture process, helps to establish a stable microenvironment for osteogenesis, and each cell type may play a unique role in bone regeneration. Our study compared the efficacy of concentrated fresh BMMNCs and cultured bone marrow‐derived mesenchymal stem cells (BMSCs) in Beagle dogs for the first time. Fifteen‐millimeter segmental bone defects were created in the animals' tibia bones. In BMMNCs group, the defects were repaired with concentrated fresh BMMNCs combined with β‐TCP (n = 5); in cultured BMSC group, with in vitro cultured and osteo‐induced BMSCs combined with β‐TCP (n = 5); in scaffold‐only group, with a β‐TCP graft alone (n = 5); and in blank group, nothing was grafted (n = 3). The healing process was monitored by X‐rays and single photon emission computed tomography. The animals were sacrificed 12 months after surgery and their tibias were harvested and analyzed by microcomputed tomography and hard tissue histology. Moreover, the microstructure, chemical components, and microbiomechanical properties of the regenerated bone tissue were explored by multiphoton microscopy, Raman spectroscopy and nanoindentation. The results showed that BMMNCs group promoted much more bone regeneration than cultured BMSC group. The grafts in BMMNCs group were better mineralized, and they had collagen arrangement and microbiomechanical properties similar to the contralateral native tibia bone. These results indicate that concentrated fresh bone marrow mononuclear cells may be superior to in vitro expanded stem cells in segmental bone defect repair.

Clustering is widely used as a knowledge discovery method in scientific studies but is not often used in architectural research. This paper applies clustering to a dataset of 129 residential layouts, which were collected from contemporary architectural practices, to reveal underlying design patterns. To achieve this, this paper introduces a novel measure for the topological properties of layouts: ‘grating difference measure’. It was benchmarked against an alternative that measures geometrical properties and the advantages are explained. The grating difference measure indicates the extent of design differences, which is used in the clustering method to obtain the distance between datapoints. The results from clustering were grouped into design schematics and qualitatively assessed, showing a convincing separation of characteristics. The method demonstrated in this paper may be used to reveal topological patterns in datasets of existing designs for both academic and practical purposes.

We report compounds 5(CG416) and 6(CG428) as two first-in-class tropomyosin receptor kinase (TRK) degraders that target the intracellular kinase domain of TRK. Degraders 5and 6reduced levels of the tropomyosin 3 (TPM3)-TRKA fusion protein in KM12 colorectal carcinoma cells and inhibited downstream PLCγ1 signaling at sub-nanomolar concentrations. Both degraders also degraded human wild-type TRKA with similar potency. Interestingly, both degraders, especially 6, showed selectivity for the degradation of endogenous TPM3-TRKA over ectopically expressed ATP/GTP binding protein-like 4 (AGBL4)-TRKB or ETS variant transcription factor 6 (ETV6)-TRKC fusion proteins in KM12 cells. Global proteomic profiling assays demonstrated that 5is highly selective for the intended target. TPM3-TRKA protein degradation induced by 5and 6was further confirmed to be mediated through cereblon and the ubiquitin-proteasome system. Compared with the parental TRK kinase inhibitor, both degraders exhibited higher potency for inhibiting growth of KM12 cells. Moreover, both 5and 6showed good plasma exposure levels in mice. Therefore, 5and 6are valuable chemical tool compounds for investigating the in vivofunction of TRK fusion during tumorigenesis. Our study also paves the way for pharmacological degradation of TRK.

The mesenchymal transcription factor forkhead box F2 (FOXF2) is a critical regulator of embryogenesis and tissue homeostasis. Our previous studies demonstrated that FOXF2 is ectopically expressed in basal-like breast cancer (BLBC) cells and that FOXF2 deficiency promotes the epithelial–mesenchymal transition and aggressiveness of BLBC cells. In this study, we found that FOXF2 controls transforming growth factor-beta (TGF-ß)/SMAD signaling pathway activation through transrepression of TGF-ß-coding genes in BLBC cells. FOXF2-deficient BLBC cells adopt a myofibroblast-/cancer-associated fibroblast (CAF)-like phenotype, and tend to metastasize to visceral organs by increasing autocrine TGF-ß signaling and conferring aggressiveness to neighboring cells by increasing paracrine TGF-ß signaling. In turn, TGF-ß silences FOXF2 expression through upregulating miR-182-5p, a posttranscriptional regulator of FOXF2and inducer of metastasis. In addition to mediating a reciprocal repression loop between FOXF2 and TGF-ß through direct transrepression by SMAD3, miR-182-5p forms a reciprocal repression loop with FOXF2 that directly transrepresses MIR182expression. Therefore, FOXF2 deficiency accelerates the visceral metastasis of BLBC through unrestricted increases in autocrine and paracrine TGF-ß signaling, and miR-182-5p expression. Our findings provide novel mechanisms underlying the roles of TGF-ß, miR-182-5p, and FOXF2 in accelerating BLBC dissemination and metastasis, and may facilitate the development of therapeutic strategies for aggressive BLBC.