A tandem activity-based sensing and labeling strategy reveals antioxidant response element regulation of labile iron pools.

Iron is an essential element for life owing to its ability to participate in a diverse array of oxidation-reduction reactions. However, misregulation of iron-dependent redox cycling can also produce oxidative stress, contributing to cell growth, proliferation, and death pathways underlying aging, cancer, neurodegeneration, and metabolic diseases. Fluorescent probes that selectively monitor loosely bound Fe(II) ions, termed the labile iron pool, are potentially powerful tools for studies of this metal nutrient; however, the dynamic spatiotemporal nature and potent fluorescence quenching capacity of these bioavailable metal stores pose challenges for their detection. Here, we report a tandem activity-based sensing and labeling strategy that enables imaging of labile iron pools in live cells through enhancement in cellular retention. Iron green-1 fluoromethyl (IG1-FM) reacts selectively with Fe(II) using an endoperoxide trigger to release a quinone methide dye for subsequent attachment to proximal biological nucleophiles, providing a permanent fluorescent stain at sites of elevated labile iron. IG1-FM imaging reveals that degradation of the major iron storage protein ferritin through ferritinophagy expands the labile iron pool, while activation of nuclear factor-erythroid 2-related factor 2 (NRF2) antioxidant response elements (AREs) depletes it. We further show that lung cancer cells with heightened NRF2 activation, and thus lower basal labile iron, have reduced viability when treated with an iron chelator. By connecting labile iron pools and NRF2-ARE activity to a druggable metal-dependent vulnerability in cancer, this work provides a starting point for broader investigations into the roles of transition metal and antioxidant signaling pathways in health and disease.

TransPTM: a transformer-based model for non-histone acetylation site prediction.

Protein acetylation is one of the extensively studied post-translational modifications (PTMs) due to its significant roles across a myriad of biological processes. Although many computational tools for acetylation site identification have been developed, there is a lack of benchmark dataset and bespoke predictors for non-histone acetylation site prediction. To address these problems, we have contributed to both dataset creation and predictor benchmark in this study. First, we construct a non-histone acetylation site benchmark dataset, namely NHAC, which includes 11 subsets according to the sequence length ranging from 11 to 61 amino acids. There are totally 886 positive samples and 4707 negative samples for each sequence length. Secondly, we propose TransPTM, a transformer-based neural network model for non-histone acetylation site predication. During the data representation phase, per-residue contextualized embeddings are extracted using ProtT5 (an existing pre-trained protein language model). This is followed by the implementation of a graph neural network framework, which consists of three TransformerConv layers for feature extraction and a multilayer perceptron module for classification. The benchmark results reflect that TransPTM has the competitive performance for non-histone acetylation site prediction over three state-of-the-art tools. It improves our comprehension on the PTM mechanism and provides a theoretical basis for developing drug targets for diseases. Moreover, the created PTM datasets fills the gap in non-histone acetylation site datasets and is beneficial to the related communities. The related source code and data utilized by TransPTM are accessible at https://www.github.com/TransPTM/TransPTM.

SlRBP1 promotes translational efficiency via SleIF4A2 to maintain chloroplast function in tomato.

Many glycine-rich RNA-binding proteins (GR-RBPs) have critical functions in RNA processing and metabolism. Here, we describe a role for the tomato (Solanum lycopersicum) GR-RBP SlRBP1 in regulating mRNA translation. We found that SlRBP1 knockdown mutants (slrbp1) displayed reduced accumulation of total chlorophyll and impaired chloroplast ultrastructure. These phenotypes were accompanied by deregulation of the levels of numerous key transcripts associated with chloroplast functions in slrbp1. Furthermore, native RNA immunoprecipitation-sequencing (nRIP-seq) recovered 61 SlRBP1-associated RNAs, most of which are involved in photosynthesis. SlRBP1 binding to selected target RNAs was validated by nRIP-qPCR. Intriguingly, the accumulation of proteins encoded by SlRBP1-bound transcripts, but not the mRNAs themselves, was reduced in slrbp1 mutants. Polysome profiling followed by RT-qPCR assays indicated that the polysome occupancy of target RNAs was lower in slrbp1 plants than in wild-type. Furthermore, SlRBP1 interacted with the eukaryotic translation initiation factor SleIF4A2. Silencing of SlRBP1 significantly reduced SleIF4A2 binding to SlRBP1-target RNAs. Taking these observations together, we propose that SlRBP1 binds to and channels RNAs onto the SleIF4A2 translation initiation complex and promotes the translation of its target RNAs to regulate chloroplast functions.

Dual and triple gene combinations of KRT5, KRT17, and S100A2 identify basal-like subtype of pancreatic ductal adenocarcinoma and correlate with survival outcome.

There is a significant difference in prognosis and response to chemotherapy between basal and classical subtypes of pancreatic ductal adenocarcinoma (PDAC). Further biomarkers are required to identify subtypes of PDAC. We selected candidate biomarkers via review articles. Correlations between these candidate markers and the PDAC molecular subtype gene sets were analyzed using bioinformatics, confirming the biomarkers for identifying classical and basal subtypes. Subsequently, 298 PDAC patients were included, and their tumor tissues were immunohistochemically stratified using these biomarkers. Survival data underwent analysis, including Cox proportional hazards modeling. Our results indicate that the pairwise and triple combinations of KRT5/KRT17/S100A2 exhibit a higher correlation coefficient with the basal-like subtype gene set, whereas the corresponding combinations of GATA6/HNF4A/TFF1 show a higher correlation with the classical subtype gene set. Whether analyzing unmatched or propensity-matched data, the overall survival time was significantly shorter for the basal subtype compared with the classical subtype (p < .001), with basal subtype patients also facing a higher risk of mortality (HR = 4.017, 95% CI 2.675-6.032, p < .001). In conclusion, the combined expression of KRT5, KRT17, and S100A2, in both pairwise and triple combinations, independently predicts shorter overall survival in PDAC patients and likely identifies the basal subtype. Similarly, the combined expression of GATA6, HNF4A, and TFF1, in the same manner, may indicate the classical subtype. In our study, the combined application of established biomarkers offers valuable insights for the prognostic evaluation of PDAC patients.

Achromatic CMOS-Integrated Four-Bit Orbital Angular Momentum Mode Detector at Three Wavelengths.

The simultaneous detection of the orbital angular momentum (OAM) and wavelength offers new opportunities for optical multiplexing. However, because of the dispersion of lens functions for Fourier transformation, the mode conversions at distinct wavelengths cannot be achieved in the same plane. Here we propose an ultracompact achromatic complementary metal oxide semiconductor (CMOS)-integrated OAM mode detector. Specifically, a spatial multiplexed scheme, randomly interleaving the phase distributions for distributing the superposed OAM modes into preset positions at distinct wavelengths, is presented. In addition, such a nanoprinted achromatic OAM detector featuring a microscale size and a short focal length can be integrated onto a CMOS chip. Consequently, the four-bit incident light beams at three discrete wavelengths (633, 532, and 488 nm) can be distinguished with a high degree of accuracy evaluated by the average standardized Euclidean distance of ∼0.75 between the analytical and target results. Our results showcase a miniaturized platform for achieving high-capacity information processing.

Dicer-like2b suppresses the wiry leaf phenotype in tomato induced by tobacco mosaic virus.

Dicer-like (DCL) proteins are principal components of RNA silencing, a major defense mechanism against plant virus infections. However, their functions in suppressing virus-induced disease phenotypes remain largely unknown. Here, we identified a role for tomato (Solanum lycopersicum) DCL2b in regulating the wiry leaf phenotype during defense against tobacco mosaic virus (TMV). Knocking out SlyDCL2b promoted TMV accumulation in the leaf primordium, resulting in a wiry phenotype in distal leaves. Biochemical and bioinformatics analyses showed that 22-nt virus-derived small interfering RNAs (vsiRNAs) accumulated less abundantly in slydcl2b mutants than in wild-type plants, suggesting that SlyDCL2b-dependent 22-nt vsiRNAs are required to exclude virus from leaf primordia. Moreover, the wiry leaf phenotype was accompanied by upregulation of Auxin Response Factors (ARFs), resulting from a reduction in trans-acting siRNAs targeting ARFs (tasiARFs) in TMV-infected slydcl2b mutants. Loss of tasiARF production in the slydcl2b mutant was in turn caused by inhibition of miRNA390b function. Importantly, silencing SlyARF3 and SlyARF4 largely restored the wiry phenotype in TMV-infected slydcl2b mutants. Our work exemplifies the complex relationship between RNA viruses and the endogenous RNA silencing machinery, whereby SlyDCL2b protects the normal development of newly emerging organs by excluding virus from these regions and thus maintaining developmental silencing.

Carbon Dots with Integrated Photothermal Antibacterial and Heat-Enhanced Antioxidant Properties for Diabetic Wound Healing.

Diabetic wounds pose a persistent challenge due to their slow healing nature, primarily caused by bacterial infection and excessive reactive oxygen species (ROS)-induced inflammation. In this study, carbon dots with synergistic antibacterial and antioxidant properties, referred to as AA-CDs, are developed specifically for diabetic wound healing using a straightforward solvothermal method. By utilizing cost-effective precursors like citric acid and ascorbic acid, AA-CDs are engineered to possess tailored functions of photothermal sterilization and ROS scavenging. The resulting AA-CDs demonstrats broad-spectrum antibacterial activity, particularly against multidrug-resistant strains, along with efficient ROS scavenging both in solution and within cells. Additionally, AA-CDs exhibits a protective effect against oxidative stress-induced damage. Notably, with a high photothermal conversion efficiency (41.18%), AA-CDs displays heat-enhanced antioxidant performance, providing not only augmented ROS scavenging but also additional protection against oxidative stress, yielding a true "1 + 1 > 2" effect. To facilitate their use in vivo, AA-CDs are incorporated into a thermally responsive hydrogel, which exhibits evident anti-inflammatory properties by modulating inflammatory factors and significantly promots the healing of diabetic wounds. This study underscores the value of integrated platforms for diabetic wound healing and highlights the potential of versatile CDs as promising therapeutic agents in biomedical applications.

Vitamin D3 promotes fish oocyte development by directly regulating gonadal steroid hormone synthesis†.

Vitamin D receptors and vitamin D3-metabolizing enzymes have been found to be highly expressed in the ovaries and spermatophores of fish. However, the role of vitamin D3 on fish gonadal development has rarely been reported. In this study, 2-month-old female zebrafish were fed with different concentrations of vitamin D3 diets (0, 700, 1400, and 11 200 IU/kg) to investigate the effects of vitamin D3 on ovarian development. The diet with 0 IU/kg vitamin D3 resulted in elevated interstitial spaces, follicular atresia, and reproductive toxicity in zebrafish ovaries. Supplementation with 700 and 1400 IU/kg of vitamin D3 significantly increased the oocyte maturation rate; upregulated ovarian gonadal steroid hormone synthesis capacity; and elevated plasma estradiol, testosterone, and ovarian vitellogenin levels. Furthermore, the current study identified a vitamin D response element in the cyp19a1a promoter and demonstrated that 1.25(OH)2D3-vitamin D response directly activated cyp19a1a production through activating the vitamin D response element. In conclusion, this study shows that an appropriate concentration of vitamin D3 can promote zebrafish ovarian development and affect vitellogenin synthesis through the vdr/cyp19a1a/er/vtg gene axis.

Deep learning radiomics under multimodality explore association between muscle/fat and metastasis and survival in breast cancer patients.

Sarcopenia is correlated with poor clinical outcomes in breast cancer (BC) patients. However, there is no precise quantitative study on the correlation between body composition changes and BC metastasis and survival. The present study proposed a deep learning radiomics (DLR) approach to investigate the effects of muscle and fat on distant metastasis and death outcomes in BC patients. Image feature extraction was performed on 4th thoracic vertebra (T4) and 11th thoracic vertebra (T11) on computed tomography (CT) image levels by DLR, and image features were combined with clinical information to predict distant metastasis in BC patients. Clinical information combined with DLR significantly predicted distant metastasis in BC patients. In the test cohort, the area under the curve of model performance on clinical information combined with DLR was 0.960 (95% CI: 0.942-0.979, P < 0.001). The patients with distant metastases had a lower pectoral muscle index in T4 (PMI/T4) than in patients without metastases. PMI/T4 and visceral fat tissue area in T11 (VFA/T11) were independent prognostic factors for the overall survival in BC patients. The pectoralis muscle area in T4 (PMA/T4) and PMI/T4 is an independent prognostic factor for distant metastasis-free survival in BC patients. The current study further confirmed that muscle/fat of T4 and T11 levels have a significant effect on the distant metastasis of BC. Appending the network features of T4 and T11 to the model significantly enhances the prediction performance of distant metastasis of BC, providing a valuable biomarker for the early treatment of BC patients.

An inhaled bioadhesive hydrogel to shield non-human primates from SARS-CoV-2 infection.

The surge of fast-spreading SARS-CoV-2 mutated variants highlights the need for fast, broad-spectrum strategies to counteract viral infections. In this work, we report a physical barrier against SARS-CoV-2 infection based on an inhalable bioadhesive hydrogel, named spherical hydrogel inhalation for enhanced lung defence (SHIELD). Conveniently delivered via a dry powder inhaler, SHIELD particles form a dense hydrogel network that coats the airway, enhancing the diffusional barrier properties and restricting virus penetration. SHIELD's protective effect is first demonstrated in mice against two SARS-CoV-2 pseudo-viruses with different mutated spike proteins. Strikingly, in African green monkeys, a single SHIELD inhalation provides protection for up to 8 hours, efficiently reducing infection by the SARS-CoV-2 WA1 and B.1.617.2 (Delta) variants. Notably, SHIELD is made with food-grade materials and does not affect normal respiratory functions. This approach could offer additional protection to the population against SARS-CoV-2 and other respiratory pathogens.

The influence of male HBV infection on sperm quality, embryonic development, and assisted reproductive outcomes.

STUDY QUESTION: What is the impact of male hepatitis B virus (HBV) infection on sperm quality, embryonic development, and assisted reproductive outcomes? SUMMARY ANSWER: Male HBV infection did not affect assisted reproductive outcomes, but HBV is capable of impairing human sperm and embryo formation in the early stages following fertilization. WHAT IS KNOWN ALREADY: HBV is found in germ cells and early embryos of patients with HBV. HBV may impair human sperm function via increasing reactive oxygen species. STUDY DESIGN, SIZE, DURATION: We conducted a retrospective cohort study of 1581 infertile couples, including 496 male patients clinically confirmed to have hepatitis B infection, and a laboratory study of effects of HBV proteins on early embryos, using human embryonic stem cells (hESCs), human sperm, and golden hamster oocytes. PARTICIPANTS/MATERIALS, SETTING, METHODS: In total, 1581 infertile couples (24-40 years of age) who were admitted to a reproductive medicine center to undergo ART for the first time from January 2019 to November 2021 were selected as the study subjects. The case group was composed of 469 couples with hepatitis B surface antigen (HBsAg)-seropositive men and seronegative women (368 for IVF and 101 for ICSI treatment). The negative control group was composed of 1112 couples where both men and women were seronegative for hepatitis B antigen. We divided these couples into three comparison groups (IVF/ICSI, IVF, and ICSI). IVF of human sperm and hamster oocytes was used to evaluate the influence of the HBV HBs protein on formation of 2-cell embryos. Mitochondrial membrane potential (MMP) of hESCs was assayed via a fluorescence intensity system. Immunofluorescence staining of the phosphorylated histone H2A.X was applied to identify DNA damage to hESCs caused by the HBV X (HBx) protein. MAIN RESULTS AND THE ROLE OF CHANCE: Sperm concentration, total sperm number, and sperm with normal morphology were decreased in the couples with HBV-infected males in couples who were undergoing IVF/ICSI (male HBV(+) vs control: 469 vs 1112 individuals; sperm number, P < 0.01; normal sperm morphology, P < 0.01), IVF (368 vs 792; sperm number, P < 0.01; normal sperm morphology, P ≤ 0.05), and ICSI (101 vs 306; sperm number, P < 0.01; normal sperm morphology, P < 0.001). There was no significant difference in the number of embryo cleavages, blastocyst formation, biochemical pregnancy rate, clinical pregnancy rate, and live-birth rate between case and control groups. The 2PN fertilization rate in IVF/ICSI (P < 0.01) and ICSI (P < 0.05) couples, and the number of 2PN-fertilized oocytes in IVF (P < 0.001) couples were lower in couples with male HBV infection compared to control couples. HBV HBs protein reduced the MMP of human sperm and decreased 2-cell embryo formation in IVF of human sperm and zona-free-hamster oocyte. A reduction in fluorescence intensity and immunofluorescence staining of phosphorylated histone H2A.X indicated that HBx caused MMP impairment and DNA damage in human early embryonic cells, respectively. LARGE SCALE DATA: N/A. LIMITATIONS, REASONS FOR CAUTION: HBV can be examined in samples of sperm or discarded IVF early embryos from HBsAg-seropositive men and seronegative women. The hESC model in vitro may not fully mimic the natural embryos in vivo. WIDER IMPLICATIONS OF THE FINDINGS: This study furthers our understanding of the influence of male HBV infection on embryonic development. Our results suggest that a semen-washing process may be necessary for male patients with HBV undergoing ART to minimize the potential negative effects of HBV infection on the early embryo. STUDY FUNDING/COMPETING INTEREST(S): This work was funded by grants from the National Natural Science Foundation of China, grant numbers 81870432 and 81570567 to X.Z., 81571994 to P.S., and 81950410640, the Natural Science Foundation of Guangdong Province, China (No. 2023A1515010660 to X.Z.), and the Li Ka Shing Shantou University Foundation (Grant No. L11112008). The authors have no conflicts of interest.

The gut microbiome modulates the transformation of microglial subtypes.

Clinical and animal studies have shown that gut microbiome disturbances can affect neural function and behaviors via the microbiota-gut-brain axis, and may be implicated in the pathogenesis of several brain diseases. However, exactly how the gut microbiome modulates nervous system activity remains obscure. Here, using a single-cell nucleus sequencing approach, we sought to characterize the cell type-specific transcriptomic changes in the prefrontal cortex and hippocampus derived from germ-free (GF), specific pathogen free, and colonized-GF mice. We found that the absence of gut microbiota resulted in cell-specific transcriptomic changes. Furthermore, microglia transcriptomes were preferentially influenced, which could be effectively reversed by microbial colonization. Significantly, the gut microbiome modulated the mutual transformation of microglial subpopulations in the two regions. Cross-species analysis showed that the transcriptome changes of these microglial subpopulations were mainly associated with Alzheimer's disease (AD) and major depressive disorder (MDD), which were further supported by animal behavioral tests. Our findings demonstrate that gut microbiota mainly modulate the mutual transformation of microglial subtypes, which may lead to new insights into the pathogenesis of AD and MDD.

Peptide ligands for the universal purification of exosomes by affinity chromatography.

Exosomes are gaining prominence as vectors for drug delivery, vaccination, and regenerative medicine. Owing to their surface biochemistry, which reflects the parent cell membrane, these nanoscale biologics feature low immunogenicity, tunable tissue tropism, and the ability to carry a variety of payloads across biological barriers. The heterogeneity of exosomes' size and composition, however, makes their purification challenging. Traditional techniques, like ultracentrifugation and filtration, afford low product yield and purity, and jeopardizes particle integrity. Affinity chromatography represents an excellent avenue for exosome purification. Yet, current affinity media rely on antibody ligands whose selectivity grants high product purity, but mandates the customization of adsorbents for exosomes with different surface biochemistry while their binding strength imposes elution conditions that may harm product's activity. Addressing these issues, this study introduces the first peptide affinity ligands for the universal purification of exosomes from recombinant feedstocks. The peptides were designed to (1) possess promiscuous biorecognition of exosome markers, without binding process-related contaminants and (2) elute the product under conditions that safeguard product stability. Selected ligands SNGFKKHI and TAHFKKKH demonstrated the ability to capture of exosomes secreted by 14 cell sources and purified exosomes derived from HEK293, PC3, MM1, U87, and COLO1 cells with yields of up to 80% and up-to 50-fold reduction of host cell proteins (HCPs) upon eluting with pH gradient from 7.4 to 10.5, recommended for exosome stability. SNGFKKHI-Toyopearl resin was finally employed in a two-step purification process to isolate exosomes from HEK293 cell fluids, affording a yield of 68% and reducing the titer of HCPs to 68 ng/mL. The biomolecular and morphological features of the isolated exosomes were confirmed by analytical chromatography, Western blot analysis, transmission electron microscopy, nanoparticle tracking analysis.

PLEK2 promotes migration and invasion in pancreatic ductal adenocarcinoma by MMP1 through IL-17 pathway.

Pancreatic ductal adenocarcinoma (PDAC) is characterized by poor prognosis primarily due to metastasis. Accumulating evidence suggests that PLEK2 acts as an oncogene in various tumors. This study aimed to investigate the effects of PLEK2 on PDAC. Expression analysis of PLEK2 was conducted using qRT-PCR, Western blot, and immunohistochemistry in PDAC. Wound healing and transwell assays were performed to evaluate the impact of PLEK2 on cell migration and invasion. A xenograft tumor model was employed to assess the in vivo proliferation of PLEK2. Additionally, the downstream pathway of PLEK2 was analyzed through RNA-seq and confirmed by Western blot analysis. The results demonstrated the upregulation of PLEK2 expression in tumor specimens. High PLEK2 expression was significantly associated with poor overall survival and advanced TNM stages. Correlation analyses revealed positive correlations between PLEK2 and TGF-ß, EGFR, and MMP1. Wound healing and transwell assays demonstrated that PLEK2 promoted PDAC cell migration and invasion, potentially through the activation of the epithelial-to-mesenchymal transition process. The in vivo experiment further confirmed that PLEK2 knockdown suppressed tumor growth. RNA-seq analysis revealed PLEK2's regulation of MMP1 and activation of p-ERK and p-STAT3, which were verified by Western blot analysis. Overall, the present study suggests that PLEK2 may play a tumor-promoting role in PDAC. These findings provide valuable insights into the molecular mechanisms of pancreatic cancer and highlight the potential of PLEK2 as a therapeutic target.

Intrapericardial Exosome Therapy Dampens Cardiac Injury via Activating Foxo3.

BACKGROUND: Mesenchymal stem cell (MSC)-derived exosomes are well recognized immunomodulating agents for cardiac repair, while the detailed mechanisms remain elusive. The Pericardial drainage pathway provides the heart with immunosurveillance and establishes a simplified model for studying the mechanisms underlying the immunomodulating effects of therapeutic exosomes. METHODS: Myocardial infarction (MI) models with and without pericardiectomy (corresponding to Tomy MI and NonTomy MI) were established to study the functions of pericardial drainage pathway in immune activation of cardiac-draining mediastinal lymph node (MLN). Using the NonTomy MI model, MSC exosomes or vehicle PBS was intrapericardially injected for MI treatment. Via cell sorting and RNA-seq (RNA-sequencing) analysis, the differentially expressed genes were acquired for integrated pathway analysis to identify responsible mechanisms. Further, through functional knockdown/inhibition studies, application of cytokines and neutralizing antibodies, western blot, flow cytometry, and cytokine array, the molecular mechanisms were studied. In addition, the therapeutic efficacy of intrapericardially injected exosomes for MI treatment was evaluated through functional and histological analyses. RESULTS: We show that the pericardial draining pathway promoted immune activation in the MLN following MI. Intrapericardially injected exosomes accumulated in the MLN and induced regulatory T cell differentiation to promote cardiac repair. Mechanistically, uptake of exosomes by major histocompatibility complex (MHC)-II+ antigen-presenting cells (APCs) induced Foxo3 activation via the protein phosphatase (PP)-2A/p-Akt/forkhead box O3 (Foxo3) pathway. Foxo3 dominated APC cytokines (IL-10, IL-33, and IL-34) expression and built up a regulatory T cell (Treg)-inducing niche in the MLN. The differentiation of Tregs as well as their cardiac deployment were elevated, which contributed to cardiac inflammation resolution and cardiac repair. CONCLUSIONS: This study reveals a novel mechanism underlying the immunomodulation effects of MSC exosomes and provides a promising candidate (PP2A/p-Akt/Foxo3 signaling pathway) with a favorable delivery route (intrapericardial injection) for cardiac repair.

A triple Fano resonance Si-graphene metasurface for multi-channel tunable ultra-narrow band sensing.

In this work, a dielectric metasurface composed of a silicon nanodisk etched with a square hole is proposed. By introducing C4v symmetry breaking, the symmetry-protected bound states in the continuum (SP-BIC) is transformed into a quasi-BIC (Q-BIC), simultaneously inducing triple Fano resonances in the near-infrared light band corresponding to one dipole and two Q-BIC resonances. The characteristics of Q-BIC resonances are elucidated through multipole decomposition and near-field distribution analysis. Subsequently, monolayer graphene is integrated into the Si metasurface. The light field in the composite metasurface can be flexibly modulated by changing the Fermi level of graphene. This modulation enables optimal transmission with an enhancement of up to 252%, while the confined electromagnetic energy experiences a remarkable increase of about 1020%. Simulation results demonstrate that the Si-graphene composite metasurface exhibits a high refractive index sensitivity of 162 nm RIU-1, accompanied by a figure of merit of 170.526 RIU-1. This composite metasurface holds promise as a high-performance sensor in the near-infrared band and has potential for application in the fields of active tunable optical devices and biochemical sensing.

Artificial intelligence automated surgical phases recognition in intraoperative videos of laparoscopic pancreatoduodenectomy.

BACKGROUND: Laparoscopic pancreatoduodenectomy (LPD) is one of the most challenging operations and has a long learning curve. Artificial intelligence (AI) automated surgical phase recognition in intraoperative videos has many potential applications in surgical education, helping shorten the learning curve, but no study has made this breakthrough in LPD. Herein, we aimed to build AI models to recognize the surgical phase in LPD and explore the performance characteristics of AI models. METHODS: Among 69 LPD videos from a single surgical team, we used 42 in the building group to establish the models and used the remaining 27 videos in the analysis group to assess the models' performance characteristics. We annotated 13 surgical phases of LPD, including 4 key phases and 9 necessary phases. Two minimal invasive pancreatic surgeons annotated all the videos. We built two AI models for the key phase and necessary phase recognition, based on convolutional neural networks. The overall performance of the AI models was determined mainly by mean average precision (mAP). RESULTS: Overall mAPs of the AI models in the test set of the building group were 89.7% and 84.7% for key phases and necessary phases, respectively. In the 27-video analysis group, overall mAPs were 86.8% and 71.2%, with maximum mAPs of 98.1% and 93.9%. We found commonalities between the error of model recognition and the differences of surgeon annotation, and the AI model exhibited bad performance in cases with anatomic variation or lesion involvement with adjacent organs. CONCLUSIONS: AI automated surgical phase recognition can be achieved in LPD, with outstanding performance in selective cases. This breakthrough may be the first step toward AI- and video-based surgical education in more complex surgeries.

Prediction of delayed graft function by early salivary microbiota following kidney transplantation.

Delayed graft function (DGF) is a frequently observed complication following kidney transplantation (KT). Our prior research revealed dynamic shifts in salivary microbiota post-KT with immediate graft function (IGF), yet its behavior during DGF remains unexplored. Five recipients with DGF and 35 recipients with IGF were enrolled. Saliva samples were collected during the perioperative period, and 16S rRNA gene sequencing was performed. The salivary microbiota of IGFs changed significantly and gradually stabilized with the recovery of renal function. The salivary microbiota composition of DGFs was significantly different from that of IGFs, although the trend of variation appeared to be similar to that of IGFs. Salivary microbiota that differed significantly between patients with DGF and IGF at 1 day after transplantation were able to accurately distinguish the two groups in the randomForest algorithm (accuracy = 0.8333, sensitivity = 0.7778, specificity = 1, and area under curve = 0.85), with Selenomonas playing an important role. Bacteroidales (Spearman's r = - 0.4872 and p = 0.0293) and Veillonella (Spearmen's r = - 0.5474 and p = 0.0125) were significantly associated with the serum creatinine in DGF patients. Moreover, the significant differences in overall salivary microbiota structure between DGF and IGF patients disappeared upon long-term follow-up. This is the first study to investigate the dynamic changes in salivary microbiota in DGFs. Our findings suggested that salivary microbiota was able to predict DGF in the early stages after kidney transplantation, which might help the perioperative clinical management and early-stage intervention of kidney transplant recipients. KEY POINTS: • Salivary microbiota on the first day after KT could predict DGF. • Alterations in salivary taxa after KT are related to recovery of renal function.

Intrapericardial long non-coding RNA-Tcf21 antisense RNA inducing demethylation administration promotes cardiac repair.

AIMS: Epicardium and epicardium-derived cells are critical players in myocardial fibrosis. Mesenchymal stem cell-derived extracellular vesicles (EVs) have been studied for cardiac repair to improve cardiac remodelling, but the actual mechanisms remain elusive. The aim of this study is to investigate the mechanisms of EV therapy for improving cardiac remodelling and develop a promising treatment addressing myocardial fibrosis. METHODS AND RESULTS: Extracellular vesicles were intrapericardially injected for mice myocardial infarction treatment. RNA-seq, in vitro gain- and loss-of-function experiments, and in vivo studies were performed to identify targets that can be used for myocardial fibrosis treatment. Afterward, a lipid nanoparticle-based long non-coding RNA (lncRNA) therapy was prepared for mouse and porcine models of myocardial infarction treatment. Intrapericardial injection of EVs improved adverse myocardial remodelling in mouse models of myocardial infarction. Mechanistically, Tcf21 was identified as a potential target to improve cardiac remodelling. Loss of Tcf21 function in epicardium-derived cells caused increased myofibroblast differentiation, whereas forced Tcf21 overexpression suppressed transforming growth factor-ß signalling and myofibroblast differentiation. LncRNA-Tcf21 antisense RNA inducing demethylation (TARID) that enriched in EVs was identified to up-regulate Tcf21 expression. Formulated lncRNA-TARID-laden lipid nanoparticles up-regulated Tcf21 expression in epicardium-derived cells and improved cardiac function and histology in mouse and porcine models of myocardial infarction. CONCLUSION: This study identified Tcf21 as a critical target for improving cardiac fibrosis. Up-regulating Tcf21 by using lncRNA-TARID-laden lipid nanoparticles could be a promising way to treat myocardial fibrosis. This study established novel mechanisms underlying EV therapy for improving adverse remodelling and proposed a lncRNA therapy for cardiac fibrosis.

[Microtubule-associated tumor suppressor 1 inhibits hemin-induced apoptosis of vascular endothelial cells via hemeoxygenase 1].

This study aimed to investigate the effects of microtubule associated tumor suppressor 1 (MTUS1) on hemeoxygenase 1 (HMOX1) expression and hemin-induced apoptosis of vascular endothelial cells and its regulatory mechanism. RNA sequencing, RT-qPCR and Western blot were used to assess altered genes of hemin binding proteins, the expression of cAMP response element-binding protein (CREB) and nuclear respiratory factor 2 (NRF2), hemin-induced HMOX1 expression in MTUS1 knockdown human umbilical vein endothelial cells (HUVEC), and the effect of overexpression of CREB and NRF2 on HMOX1 expression in MTUS1 knockdown 293T cells. The effect of MTUS1 or HMOX1 knockdown on hemin-induced apoptosis in HUVEC, and the overexpression of NRF2 on hemin-induced apoptosis in MTUS1 knockdown 293T cells were assayed with CCK8 and Western blot. The results showed that MTUS1 was knocked down significantly in HUVEC by siRNA (P < 0.01), accompanied by decreased HMOX1 expression (P < 0.01). The increased HMOX1 expression induced by hemin was also inhibited by MTUS1 knockdown (P < 0.01). And the apoptosis of HUVEC induced by hemin was amplified by MTUS1 or HMOX1 knockdown (P < 0.01). Moreover the expression of CREB and NRF2 were both inhibited by MTUS1 knockdown in HUVEC (P < 0.01). The decreased HMOX1 regulated by MTUS1 knockdown could be rescued partly by overexpression of NRF2 (P < 0.01), however, not by overexpression of CREB. And the MTUS1 knockdown mediated decreased 293T cells viability induced by hemin could be partly rescued by NRF2 overexpression (P < 0.01). These results suggest that MTUS1 can inhibit hemin-induced apoptosis of HUVEC, and the mechanism maybe related to MTUS1/NRF2/HMOX1 pathway.