Two-dimensional lead halide perovskite lateral homojunctions enabled by phase pinning.

Two-dimensional organic-inorganic hybrid halide perovskites possess diverse structural polymorphs with versatile physical properties, which can be controlled by order-disorder transition of the spacer cation, making them attractive for constructing semiconductor homojunctions. Here, we demonstrate a space-cation-dopant-induced phase stabilization approach to creating a lateral homojunction composed of ordered and disordered phases within a two-dimensional perovskite. By doping a small quantity of pentylammonium into (butylammonium)2PbI4 or vice versa, we effectively suppress the ordering transition of the spacer cation and the associated out-of-plane octahedral tilting in the inorganic framework, resulting in phase pining of the disordered phase when decreasing temperature or increasing pressure. This enables epitaxial growth of a two-dimensional perovskite homojunction with tunable optical properties under temperature and pressure stimuli, as well as directional exciton diffusion across the interface. Our results demonstrate a previously unexplored strategy for constructing two-dimensional perovskite heterostructures by thermodynamic tuning and spacer cation doping.

Accurate detection and grading of pterygium through smartphone by a fusion training model.

BACKGROUND/AIMS: To improve the accuracy of pterygium screening and detection through smartphones, we established a fusion training model by blending a large number of slit-lamp image data with a small proportion of smartphone data. METHOD: Two datasets were used, a slit-lamp image dataset containing 20 987 images and a smartphone-based image dataset containing 1094 images. The RFRC (Faster RCNN based on ResNet101) model for the detection model. The SRU-Net (U-Net based on SE-ResNeXt50) for the segmentation models. The open-cv algorithm measured the width, length and area of pterygium in the cornea. RESULTS: The detection model (trained by slit-lamp images) obtained the mean accuracy of 95.24%. The fusion segmentation model (trained by smartphone and slit-lamp images) achieved a microaverage F1 score of 0.8981, sensitivity of 0.8709, specificity of 0.9668 and area under the curve (AUC) of 0.9295. Compared with the same group of patients' smartphone and slit-lamp images, the fusion model performance in smartphone-based images (F1 score of 0.9313, sensitivity of 0.9360, specificity of 0.9613, AUC of 0.9426, accuracy of 92.38%) is close to the model (trained by slit-lamp images) in slit-lamp images (F1 score of 0.9448, sensitivity of 0.9165, specificity of 0.9689, AUC of 0.9569 and accuracy of 94.29%). CONCLUSION: Our fusion model method got high pterygium detection and grading accuracy in insufficient smartphone data, and its performance is comparable to experienced ophthalmologists and works well in different smartphone brands.

Thromboembolic events following a pit viper bite from Protobothrops mucrosquamatus (Taiwan Habu): A report of two cases.

Protobothrops mucrosquamatus, also known as the Taiwan Habu, is a venomous snake prevalent in Taiwan. It is accountable for most snakebites in the region. The toxin of the Taiwan Habu has significant hemorrhagic potential. However, patients bitten by this snake often suffer more local injuries than systemic ones. This report presents two cases of individuals bitten by the Taiwan Habu who subsequently experienced thromboembolism. In the first case, an 88-year-old male, bitten on his fourth toe, suffered a cerebral infarction 32 hours post-bite. In the second case, an 82-year-old female, bitten on her ankle, experienced cardiac arrest 19 hours later. Both patients promptly received antivenom and showed no signs of coagulopathy either before or after the snakebite. However, elevated coagulation factor VIII levels were observed in the first case. Our aim is to understand the mechanism behind these thromboembolic events. This report emphasizes the unusually high level of coagulation factor VIIIa and highlights the need for further investigation into the mechanisms involved. Consequently, physicians should assess the risk of thromboembolic events in snakebite patients by evaluating coagulation factors during treatment.

Volatile Droplets on Water are Sculpted by Vigorous Marangoni-Driven Subphase Flow.

The shapes of highly volatile oil-on-water droplets become strongly asymmetric when they are out of equilibrium. The unsaturated organic vapor atmosphere causes evaporation and leads to a strong Marangoni flow in the bath, unlike that previously seen in the literature. Inspecting these shapes experimentally on millisecond and submillimeter time and length scales and theoretically by scaling arguments, we confirm that Marangoni-driven convection in the subphase mechanically stresses the droplet edges to an extent that increases for organic droplets of smaller contact angle and accordingly smaller thickness. The viscous stress generated by the subphase overcomes the thermodynamic Laplace pressure. The oil droplets develop copious regularly spaced fingers, and these fingers develop spike-shaped and branched treelike structures. Unlike this behavior for single-component (surfactant-free) oil droplets, droplets composed of two miscible (surfactant-free) organic liquids develop a rim of the less volatile component along the droplet perimeter, from which jets of monodisperse smaller droplets eject periodically due to the Rayleigh-Plateau instability. When evaporation shrinks droplets to µm size, their shapes fluctuate chaotically, and ellipsoidal shapes rupture into smaller daughter droplets when subphase convection flow pulls them in opposite directions. The shape of the evaporating oil droplets is kneaded and sculpted by vigorous flow in the water subphase.

A Fully Automatic Estimation of Tear Meniscus Height Using Artificial Intelligence.

Purpose: Accurate quantification measurement of tear meniscus is vital for the precise diagnosis of dry eye. In current clinical practice, the measurement of tear meniscus height (TMH) relies on doctors' manual operation. This study aims to propose a novel automatic artificial intelligence (AI) system to evaluate TMH. Methods: A total of 510 photographs obtained by the oculus camera were labeled. Three thousand and five hundred images were finally attained by data enhancement to train the neural network model parameters, and 60 were used to evaluate the model performance in segmenting the cornea and tear meniscus region. One hundred images were used to test generalization ability of the model. We modified a segmentation model of the cornea and the tear meniscus based on the UNet-like network. The output of the segmentation model is followed by a calculation module that calculates and reports the TMH. Results: Compared with ground truth (GT) manually labeled by clinicians, our modified model achieved a Dice Similarity Coefficient (DSC) and Intersection over union (Iou) of 0.99/0.98 in the corneal segmentation task and 0.92/0.86 for the detection of tear meniscus on the validation set, respectively. On the test set, the TMH automatically measured by our AI system strongly correlates with the results manually calculated by the ophthalmologists. Conclusions: We developed a fully automated and reliable AI system to obtain TMH. After large-scale clinical testing, our method could be used for dry eye screening in clinical practice.

Single-walled carbon nanotubes synthesized by laser ablation from coal for field-effect transistors.

Single-walled carbon nanotubes (SWCNTs) have been attracting extensive attention due to their excellent properties. We have developed a strategy of using coal to synthesize SWCNTs for high performance field-effect transistors (FETs). The high-quality SWCNTs were synthesized by laser ablation using only coal as the carbon source and Co-Ni as the catalyst. We show that coal is a carbon source superior to graphite with higher yield and better selectivity toward SWCNTs with smaller diameters. Without any pre-purification, the as-prepared SWCNTs were directly sorted based on their conductivity and diameter using either aqueous two-phase extraction or organic phase extraction with PCz (poly[9-(1-octylonoyl)-9H-carbazole-2,7-diyl]). The semiconducting SWCNTs sorted by one-step PCz extraction were used to fabricate thin film FETs. The transformation of coal into FETs (and further integrated circuits) demonstrates an efficient way of utilizing natural resources and a marvelous example in green carbon technology. Considering its short steps and high feasibility, it presents great potential in future practical applications not limited to electronics.

Road traffic flow prediction based on dynamic spatiotemporal graph attention network.

To improve the prediction accuracy of traffic flow under the influence of nearby time traffic flow disturbance, a dynamic spatiotemporal graph attention network traffic flow prediction model based on the attention mechanism was proposed. Considering the macroscopic periodic characteristics of traffic flow, the spatiotemporal features are extracted by constructing spatiotemporal blocks with an adjacent period, daily period, and weekly period respectively. The spatiotemporal block is mainly composed of a two-layer graph attention network and a gated recurrent unit to capture the hidden features of space and time. In space, based on considering adjacent road segments, the Pearson correlation coefficient is used to capture the hidden correlation characteristics between non-adjacent road segments according to a certain time step. In terms of time, due to the random disturbance of traffic flow at the micro level, the attention mechanism is introduced to use the adjacent time as the query matrix to weight the output characteristics of daily cycle and weekly cycle, and the three are connected in series to output the prediction results through the linear layer. Finally, the experimental results on the public data sets show that the proposed model is superior to the six baseline models.

Development and validation of a nomogram for predicting internal mammary sentinel node metastasis in breast cancer patients.

OBJECTIVE: Internal mammary nodes are important in breast cancer prognosis, but their diagnosis is often missed in clinical practice, leading to inaccurate staging and treatment. We developed a validated nomogram to predict the presence of internal mammary sentinel nodes (IMSN) metastasis. METHODS: A total of 864 sequential IMSN biopsy procedures from a prospective studies database of 1505 cases were used for model development and validation. Multivariable logistic regression was performed on 519 sequential IMSN biopsy procedures from multi-center data between August 2018 and July 2022 to predict the presence of IMSN metastasis. A nomogram was developed based on the logistic regression model and subsequently applied to 345 sequential IMSN biopsy procedures from single-center data between November 2011 and July 2018. The model's discrimination was assessed using the area under the receiver operating characteristic curve. RESULTS: The overall frequency of IMSN metastasis was 17.0% in our study. A predictive model for IMSN metastasis was constructed using tumor size, tumor location, lymphovascular invasion, the number of positive axillary nodes (P < 0.05 for all variables in multivariate analysis), and histological grade (P < 0.05 only in univariate analysis). The nomogram was accurate, with a concordance index of 0.84 in the bootstrapping analysis and an area under the receiver operating characteristic curve of 0.80 in the validation population. CONCLUSION: Our nomogram provides an accurate and validated multivariable predictive model for estimating the individual likelihood of having IMSN metastasis. This may be useful for personalized treatment decisions regarding internal mammary radiotherapy in breast cancer patients.

Eif2s3y alleviated LPS-induced damage to mouse testis and maintained spermatogenesis by negatively regulating Adamts5.

Eif2s3y (eukaryotic translation initiation factor 2, subunit 3, structural gene Y-linked, Eif2s3y) is an essential gene for spermatogenesis. Early studies have shown that Eif2s3y can promote the proliferation of spermatogonial stem cells (SSCs) and can replace the Y chromosome together with sex-determining region Y (Sry) to transform SSCs into round spermatozoa. We injected lentiviral particles into the seminiferous tubules of mouse testes by sterile surgery surgically to establish overexpressing Eif2s3y testes. And then the mice were intraperitoneally injected with LPS to established the model of testis inflammation. Through RNA sequencing, qRT-PCR analysis, Western blot, co-culture etc., we found that Eif2s3y alleviated LPS-induced damage in mouse testes and maintained spermatogenesis. In testes with Eif2s3y overexpression, the seminiferous tubules were more regularly organized after exposure to LPS compared with the control. Eif2s3y performs its function by negatively regulating Adamts5 (a disintegrin and metalloproteinase containing a thrombospondin-1 motif), an extracellular matrix-degrading enzyme. ADAMTS5 shows a disruptive effect when the testis is exposed to LPS. Overexpression of Eif2s3y inhibited the TLR4/NFκB signaling pathway in the testis in response to LPS. Generally, our research shows that Eif2s3y protects the testis from LPS and maintains spermatogenesis by negatively regulating Adamts5.

Profiling of miRNAs and their interfering targets in peripheral blood mononuclear cells from patients with chronic myeloid leukaemia.

Introduction: MicroRNAs may be implicated in the acquisition of drug resistance in chronic myeloid leukemia as they regulate the expression of not only BCR-ABL1 but also genes associated with the activation of drug transfer proteins or essential signaling pathways. Methods: To understand the impact of specifically expressed miRNAs in chronic myeloid leukemia and their target genes, we collected peripheral blood mononuclear cells (PBMC) from patients diagnosed with chronic myeloid leukemia (CML) and healthy donors to determine whole miRNA expression by small RNA sequencing and screened out 31 differentially expressed microRNAs (DE-miRNAs) with high expression. With the utilization of miRNA set enrichment analysis tools, we present here a comprehensive analysis of the relevance of DE-miRNAs to disease and biological function. Furthermore, the literature-based miRNA-target gene database was used to analyze the overall target genes of the DE-miRNAs and to define their associated biological responses. We further integrated DE-miRNA target genes to identify CML miRNA targeted gene signature singscore (CMTGSS) and used gene-set enrichment analysis (GSEA) to analyze the correlation between CMTGSS and Hallmark gene-sets in PBMC samples from clinical CML patients. Finally, the association of CMTGSS stratification with multiple CML cell lineage gene sets was validated in PBMC samples from CML patients using GSEA. Results: Although individual miRNAs have been reported to have varying degrees of impact on CML, overall, our results show that abnormally upregulated miRNAs are associated with apoptosis and aberrantly downregulated miRNAs are associated with cell cycle. The clinical database shows that our defined DE-miRNAs are associated with the prognosis of CML patients. CMTGSS-based stratification analysis presented a tendency for miRNAs to affect cell differentiation in the blood microenvironment. Conclusion: Collectively, this study defined differentially expressed miRNAs by miRNA sequencing from clinical samples and comprehensively analyzed the biological functions of the differential miRNAs in association with the target genes. The analysis of the enrichment of specific myeloid differentiated cells and immune cells also suggests the magnitude and potential targets of differentially expressed miRNAs in the clinical setting. It helps us to make links between the different results obtained from the multi-faceted studies to provide more potential research directions.

RNF128 regulates neutrophil infiltration and myeloperoxidase functions to prevent acute lung injury.

Acute lung injury (ALI) is characterised by severe pulmonary inflammation, alveolar-capillary barrier disruption, and pulmonary oedema. Therefore, establishing effective therapeutic targets for ALI prevention is crucial. The present study reports a novel function of RNF128 in regulating LPS-induced ALI. Severe lung damage and increased immune cell infiltration were detected in RNF128-deficient mice. In vitro experiments revealed that RNF128 inhibits neutrophil activation by binding to myeloperoxidase (MPO) and reducing its levels and activity. Moreover, RNF128 regulates alveolar macrophage activation and neutrophil infiltration by interacting with TLR4, targeting it for degradation, and inhibiting NF-κB activation, hence decreasing pro-inflammatory cytokines. Our results demonstrate for the first time that RNF128 is a negative regulator of MPO and TLR4 in neutrophils and alveolar macrophages, respectively. However, AAV9-mediated RNF128 overexpression alleviated lung tissue damage and reduced inflammatory cell infiltration. Thus, RNF128 is a promising therapeutic candidate for pharmacological interventions in ALI.

MMPs, ADAMs and ADAMTSs are associated with mammalian sperm fate.

Metalloproteinases include matrix metalloproteinases and disintegrin metalloproteinases. They are important members of the ECM degradation and reconstruction process and are associated with tissue development and disease. The ECM is a three-dimensional network of large molecules consisting of a variety of proteins. It is a physical scaffold for organs, and all types of cells can be found within the ECM. The testicle, where sperm are produced, is an organ that is constantly in dynamic flux. Metalloproteinases can regulate testicular tissue development and the maturation of sperm by affecting the ECM. Metalloproteinase disorders can lead to cryptorchidism, azoospermia, poor semen quality and other diseases. As a member of the metalloproteinase family, ADAMTS plays an important role in testicular slippage to the scrotum. ADAM is involved in the fertilization process, and excessive MMP can damage the BTB. In the testis, metalloproteinase stability represents the stability of the extracellular microenvironment in which germ cells are located and is associated with reproductive function. Metalloproteinases have a definite relationship with male reproduction, but the underlying mechanism is still unclear. This paper summarizes the literature on various metalloproteinases in testicular tissue physiology and pathology to elucidate their role in reproductive function and male reproductive mechanisms.

Oil-on-water droplets faceted and stabilized by vortex halos in the subphase.

For almost 200 y, the dominant approach to understand oil-on-water droplet shape and stability has been the thermodynamic expectation of minimized energy, yet parallel literature shows the prominence of Marangoni flow, an adaptive gradient of interfacial tension that produces convection rolls in the water. Our experiments, scaling arguments, and linear stability analysis show that the resulting Marangoni-driven high-Reynolds-number flow in shallow water overcomes radial symmetry of droplet shape otherwise enforced by the Laplace pressure. As a consequence, oil-on-water droplets are sheared to become polygons with distinct edges and corners. Moreover, subphase flows beneath individual droplets can inhibit the coalescence of adjacent droplets, leading to rich many-body dynamics that makes them look alive. The phenomenon of a "vortex halo" in the liquid subphase emerges as a hidden variable.

Controlled Preparation of Single-Walled Carbon Nanotubes as Materials for Electronics.

Single-walled carbon nanotubes (SWCNTs) are of particular interest as channel materials for field-effect transistors due to their unique structure and excellent properties. The controlled preparation of SWCNTs that meet the requirement of semiconducting and chiral purity, high density, and good alignment for high-performance electronics has become a key challenge in this field. In this Outlook, we outline the efforts in the preparation of SWCNTs for electronics from three main aspects, structure-controlled growth, selective sorting, and solution assembly, and discuss the remaining challenges and opportunities. We expect that this Outlook can provide some ideas for addressing the existing challenges and inspire the development of SWCNT-based high-performance electronics.

Effects of Medium-Chain Fatty Acid Glycerides on Nutrient Metabolism and Energy Utilization in Weaned Piglets.

Weaning stress induces the depressed digestive and absorptive capacity and insufficient intestinal energy supply. Medium-chain fatty acid glycerides have shown to improve the growth performance and intestinal barrier function of weaned piglets in the previous study. This study was aimed to investigate the regulation of medium-chain fatty acid glyceride on the nutrient absorption and energy utilization of weaned piglets. Nighty healthy weaned piglets were randomly assigned into five treatments: NP (Normal protein, normal-protein diet no antibiotics included); NC (Negative control, low-protein diet no antibiotics included); PC (Positive control, low-protein diet +75 mg/kg quinocetone, 20 mg/kg virginiamycin and 50 mg/kg aureomycin); MCT (tricaprylin + tricaprin group, low-protein diet + tricaprylin + tricaprin); GML (glycerol monolaurate group, low-protein diet + glycerol monolaurate). The results showed that GML treatment increased the ALP activity, concentrations of serine and methionine, MCT treatment increased concentrations of serine and 3-methyl-histidine but decreased TG concentration in serum. MCT and GML supplementations significantly promoted the lipase activity in the jejunum and ileum, as well as the AMP content in the ileal mucosa. GML addition significantly decreased the contents of butyric acid, isobutyric acid and total volatile fatty acid. In addition, medium chain fatty acid glycerides altered gene expressions involved in lipid metabolism, which showing the increases of AMPK2, CD36 and CGI58 and the decreases of MGAT2 and DGAT2 in the liver, as well as the increases of CD36, CGI58, MGAT2 and DGAT2 in the subcutaneous adipose tissue. These findings showed that medium-chain fatty acid glyceride can effectively improve the absorption of nutrients and lipid metabolism of piglets to meet the energy demand of weaned piglets, and then regulate the growth and development of weaned piglets.

[Identification of the potential distribution area of Cunninghamia lanceolata in China under climate change based on the MaxEnt model]. / 基于MaxEnt模型预测气候变化下杉木在中国的潜在地理分布.

Based on the distribution records of Cunninghamia lanceolata, we used the maximum Entropy (MaxEnt) model and geographic information system (GIS) methods, combined with environmental factors such as climate and terrain, to predict the potential distribution areas suitable for C. lanceolata under current and future climate scenarios. The results showed that annual precipitation was the most important factor driving the distribution of C. lanceolata. Under the current climate scenario, the total area of suitable for C. lanceolata growth was about 3.28 million km2, accounting for about 34.5% of the total land area of China. Among all the suitable areas, the lowly, intermediately, and highly suitable areas accounted for 18.3%, 29.7% and 52.0% of the total, respectively. Under future climate scenarios, the suitable area of C. lanceolata would increase, showing a clear trend of northward expansion in China. A concentrated and contiguous distribution region highly suitable for C. lanceolata would appear in the humid subtropical areas of southern China. The model was tested by the receiver operating characteristic curve (ROC). The average area under the curve of ROC of the training set was 0.91, showing high reliability.

Patients with degenerative cervical myelopathy exhibit neurophysiological improvement upon extension and flexion: a retrospective cohort study with a minimum 1-year follow-up.

BACKGROUND: Cervical extension and flexion are presumably harmful to patients with degenerative cervical myelopathy (DCM) because they worsen medullary compression visible on dynamic magnetic resonance imaging (MRI). Dynamic somatosensory evoked potentials (SSEPs) are an objective tool to measure the electrophysiological function of the spinal cord at different neck positions. In contrast to previous hypotheses, a considerable proportion of patients with DCM present improved SSEPs upon extension and flexion compared to a neutral position. METHODS: Patients with DCM who underwent preoperative dynamic SSEP examinations and subsequent decompression surgeries between 2015 and 2019 were retrospectively evaluated. We compared extension and flexion SSEPs with neutral SSEPs in each patient and classified them into extension-improved (EI) or extension-nonimproved (EN) and flexion-improved (FI) or flexion-nonimproved (FN) groups. Preoperative clinical evaluations, decompression surgical methods and one-year follow-up clinical data were recorded. Cervical spondylolisthesis and cervical alignment types were evaluated on plain cervical lateral radiographs. The number of stenotic segments, Mühle stenosis grade and disc degeneration stage of the most severe segment, and presence of ligamentum flavum hypertrophy and intramedullary T2 weighted imaging (T2WI) hyperintensity were evaluated on lateral and axial MRI. Data were compared between the EN and EN groups or FI and FN groups with T-tests, chi-square tests or Kruskal-Wallis tests. Prediction criteria were determined with logistic regression analyses. RESULTS: Forty-nine patients were included, and 9 (18.4%) and 11 (22.4%) showed improved extension and flexion SSEPs compared to their own neutral SSEPs, respectively. Interestingly, EI or FI patients had significantly better one-year postoperative mJOA recoveries than EN or FN patients (T-test, P < 0.001). Moreover, the disease duration (T-test, P = 0.024), involved segment number (Kruskal-Wallis test, P < 0.001), and cervical alignment type (chi-square test, P = 0.005) varied significantly between the EI and EN groups. The FI group presented a significantly higher Mühle stenosis grade than the FN group (Kruskal-Wallis test, P = 0.038). Furthermore, ≤ 2 involved segments and straight or sigmoid cervical alignment were significant criteria predicting improved extension SSEPs (probability: 85.7%), while Mühle stenosis Grade 3 and disease duration ≤6 months were significant criteria predicting improved flexion SSEPs (probability: 85.7%). CONCLUSIONS: Our findings provide evidence for neurophysiological improvement in patients with DCM at extension and flexion and its significance in predicting prognoses. Moreover, certain clinical and radiographic criteria may help predict neurophysiological improvement upon extension or flexion. TRIAL REGISTRATION: " [2020]151 ". Retrospectively registered on April 30, 2020.

The association between metabolic risk factors, nonalcoholic fatty liver disease, and the incidence of liver cancer: a nationwide population-based cohort study.

BACKGROUND AND AIMS: Liver cancer is a detrimental complication in patients with chronic viral hepatitis and alcoholic or nonalcoholic fatty liver disease (NAFLD). However, metabolic risk factors underlying NAFLD usually cause substantial differences in their clinical outcomes. Recently, several studies have used a novel definition of metabolic dysfunction-associated fatty liver disease (MAFLD) to reassess patients with NAFLD and pointed out the importance of metabolic risk factors. Since patients with NAFLD, MAFLD, or metabolic syndrome (MetS) have different burden of metabolic risk factors, it is crucial to decipher the risk of developing hepatic complications in these populations. METHODS: Through a longitudinal nationwide cohort study, the risk of liver cancer was investigated in patients with MetS alone, NAFLD alone, overlap NAFLD/MAFLD, and coexisting MetS and NAFLD. The general characteristics, comorbidities, and incidence of liver cancer were also compared. RESULTS: Intriguingly, patients diagnosed with MetS alone did not have a significant risk of developing HCC compared to control individuals, while patients with NAFLD alone, NAFLD/MAFLD, and coexisting NAFLD and MetS exhibited 6.08-, 5.81-, and 15.33-fold risks of developing HCC, respectively. Apart from metabolic risk factors, renal function status and liver cirrhosis were the independent risk factors for the development of HCC among these groups. CONCLUSION: Our data emphasize that metabolic dysfunction has a significant impact on hepatocarcinogenesis in patients with NAFLD. Moreover, coexisting multiple metabolic risk factors would dampen the risk of developing HCC in patients with NAFLD. Closely tracing HCC formation through laboratory examination or imaging is crucial in these patients.

Characterization and bioassays of extracellular vesicles extracted by tangential flow filtration.

Aim: To evaluate the efficiency of tangential flow filtration (TFF) in improving the yield of human umbilical cord mesenchymal stem cell (hucMSC)-derived extracellular vesicles (EVs) while promoting cell regeneration under oxidative stress. Methods: HucMSC-EVs were extracted from supernatants by ultracentrifugation (UC-EVs) and TFF (TFF-EVs), followed by feature characterization and bioactivity assays. Results: The yield of TFF-EVs increased 18-times compared with that of UC-EVs. TFF-EVs displayed proliferation-promoting ability similar to that of UC-EVs in the damaged HaCaT cell model with ultraviolet radiation B (UVB) and H2O2. Furthermore, the antiapoptotic effects of TFF-EVs were improved, whereby the apoptosis rate exhibited a 3.7-fold decrease. Conclusion: HucMSC-EVs extracted by TFF show a higher yield and rejuvenate the damaged HaCaT cells induced by oxidative stress.

Plain language summary The progresses in regenerative medicine will enable a perfect repair of burns. Stem cells release extracellular vesicles around injured tissues to improve its structural and functional repair. But the current methods for vesicles enrichment are not efficient enough to meet the needs of investigation. Here we isolated the vesicles from the stem cells supernatants by either traditional method or ultrafiltration. We found that the vesicles isolated with ultrafiltration method displayed a similar cell proliferation ability of that with the traditional one. The output of the vesicles or its anti-aging capability has increased 18- or 3.7-times respectively. Therefore, the scalable and effective isolation method described here may facilitate the successful medical translation of the vesicles for clinical use.