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Dip catalysts, in which the catalytic species are immobilized on solid planar supports, have drawn increasing attention due to their ease of fabrication, excellent catalytic performance, convenient separation and reusability, and environmental friendliness. A special feature is that they can turn the reaction on/off instantly by simple insertion/removal from the reaction medium. Embedding metal catalysts in biodegradable films that act as dip catalysts in organic reactions is relatively new, and therefore the facilitation of their use is necessary. Biodegradable carboxymethylcellulose (CMC) and polyvinyl alcohol (PVA) have film-forming properties due to their inter/intramolecular hydrogen bonds between numerous carboxylic and hydroxy groups. Citric acid (CA), a biodegradable tricarboxylic acid, is widely used as a crosslinker due to its esterification of hydroxy groups of polymers. To obtain biodegradable dip catalysts, we propose the incorporation of CA into a CMC–PVA composite film to enhance mechanical strength through cross-linking CMC and PVA, and to provide sufficient carboxylic and hydroxy groups for the coordination of Cu(II) and Pd(II) ions, thereby yielding Cu@CMC–CA–PVA and Pd@CMC–CA–PVA dip catalysts. Both dip catalysts were extensively characterized using ICP-AES, XPS, FT-IR, XRD, TGA, FE-SEM, TEM, and EDS analysis. The XPS analysis confirmed Cu(I) in the fresh Cu@CMC–CA–PVA catalyst, while the used sample exhibited a mixture of Cu(I) and Cu(II), likely due to partial oxidation of Cu(I) during the reaction under air conditions. Similarly, Pd(II) ions immobilized on the fresh Pd@CMC–CA–PVA were reduced to Pd(0) nanoparticles (NPs) by hydroxy groups of CMC and PVA with a high average diameter distribution of 6.53 nm. The catalytic activity of both dip catalysts was firstly evaluated separately for the aldehyde-alkyne-amine (A3) coupling reactions and Suzuki–Miyaura cross-couplings. The results demonstrated that both Cu@CMC–CA–PVA and Pd@CMC–CA–PVA catalysts have good catalytic activity to give excellent yields. In addition, these dip catalysts were easily retrieved with tweezers from the reaction system to turn off reaction and re-introduced in successive batches to turn on the reaction for repeated use. After six recycles, the catalysts still maintain good performance without noticeable loss in catalytic activity. These facilely prepared, conveniently deployed, highly active, good recyclable, and eco-friendly dip catalysts are expected to hold promise as practical tools in organic synthesis. A composite film comprising carboxymethylcellulose (CMC), polyvinyl alcohol (PVA), and citric acid (CA) enables the fabrication of Cu@CMC–CA–PVA and Pd@CMC–CA–PVA dip catalysts, featuring sufficient carboxylic and hydroxy groups for coordination with Cu(II) and Pd(II) ions, respectively. Both catalysts exhibit strong activity in A3 coupling reactions and Suzuki–Miyaura cross couplings. [ABSTRACT FROM AUTHOR]

Purpose To systematically review the effect of vitamin D supplementation on diabetic foot ulcer (DFU) healing. Methods The PubMed, Web of Science, Science direct, Ebsco host, CNKI, WanFang, VIP, and CBM databases were electronically searched to collect randomized controlled trials (RCTs) on the impact of vitamin D supplementation on DFUs from inception to 19 November 2022. Two researchers independently screened the literature, extracted the data and assessed the risk of bias of the included studies. Meta-analysis was then performed by using RevMan 5.3 software. Results A total of seven studies involving 580 patients were included. The results of meta-analysis showed that compared with control group, the wound healing efficiency rate (RR = 1.42, 95%CI 1.03 to 1.95, P  = 0.03) and wound reduction rate (MD = 13.11, 95%CI 4.65 to 21.56, P < 0.01) of the experimental group were higher; the change values of the wound area (MD = −3.29, 95%CI −4.89 to 1.70, P < 0.01) and 25 (OH) D (MD = 9.63, 95%CI 6.96 to 12.31, P < 0.01) were larger. Supplementation of vitamin D on DFU patients can improve glucose metabolism and insulin indexes: hemoglobin A1c (MD = −0.44, 95%CI -0.62 to −0.26, P < 0.01), fasting insulin (MD = −3.75, 95%CI −5.83 to −1.67, P < 0.01), HOMA - β (MD = −5.14, 95%CI −8.74 to −1.54, P < 0.01), and quantitative insulin sensitivity check index (MD = 0.02, 95%CI 0.01 to 0.02, P < 0.01). It can also improve inflammation and oxidative stress markers: high sensitivity C-reactive protein (MD = −0.83, 95%CI −1.06 to −0.59, P < 0.01), erythrocyte sedimentation rate (MD = −15.74, 95%CI −21.78 to −9.71, P <0.01), nitric oxide (MD = 1.81, 95%CI 0.07 to 3.55, P  = 0.04), and malondialdehyde (MD = −0.43, 95%CI -0.61 to −0.24, P <0.01). There was no statistically significant difference in changes of fasting plasma glucose, homeostasis model of assessment-insulin resistance, total antioxidant capacity, glutathione, very low density lipoprotein cholesterol, low density lipoprotein cholesterol, and high density lipoprotein cholesterol (P >0.05). Conclusion The current evidence suggests that vitamin D supplementation can significantly promote DFU healing by lowering blood sugar and alleviating inflammation and oxidative stress. Key messages What is already known on this topic Diabetic foot ulcer (DFU) is a major complication of diabetes mellitus, with high morbidity, mortality and resource utilization. Vitamin D has the effect of lowering blood sugar, improving insulin sensitivity, and increasing anti-inflammatory response. Clinical research on vitamin D supplementation for the treatment of DFU is increasing, but due to the lack of combing and integration, the actual efficacy of vitamin D in patients is unclear. What this study adds This meta-analysis has shown that vitamin D supplementation can significantly promote DFU healing by lowering blood glucose and alleviating inflammation and oxidative stress. How this study might affect research, practice or policy This study preliminarily found the effectiveness of vitamin D supplementation on the healing of DFU, which can provide a reference for the treatment of DFU by medical staff. [ABSTRACT FROM AUTHOR]

Inspired by the multienzymatic relay catalysis in nature, herein, we reported a pioneering bio‐inspired Cu/Pd bimetallic composite microspheres (Cu/CMC@Pd/C) as a simple and efficient relay catalyst for the homo‐coupling of arylboronic acids. In this composite, Pd/C was encapsulated by Cu(II)‐crosslinking carboxymethyl cellulose (Cu/CMC). Cu/CMC@Pd/C microspheres were easily achieved by adding a mixture solution of Pd/C and carboxymethyl cellulose into a Cu(II) solution through an ion exchange reaction between carboxylate groups of CMC and Cu(II) ions. The morphology and composition of the as‐prepared Cu/CMC@Pd/C microspheres were well characterized using various analytical tools such as FT‐IR, XRD, XPS, SEM, TEM, elemental mapping, EDS, and ICP‐AES. The analysis indicated that the composite microspheres have a porous structure and Pd/C is uniformly distributed within the interior of the composite microspheres. The porous structure facilitates mass transfer of the substrate and increases the contact area of the catalyst, thus improving reaction efficiency. The performance of Cu/CMC@Pd/C microspheres was assessed in the homo‐coupling of arylboronic acid for the synthesis of symmetric biaryl without the need for an aryl halide as a partner. This process mimics a multienzyme catalysis through a relay Cu(I)‐catalyzed halogenation of one portion of arylboronic acid and a Pd(0)‐catalyzed Suzuki–Miyaura cross‐coupling between the in situ generated aryl halide and another portion of arylboronic acid. The results showed that this bio‐inspired Cu/CMC@Pd/C has excellent relay catalytic activity with tolerance of broad functional groups, producing the desired symmetrical biaryls in excellent yields within a short reaction time under mild conditions. Moreover, the catalyst can be easily recovered through simple filtration and still has good catalytic activity after six cycles. Consequently, this innovative pseudo‐homogeneous Cu/Pd relay catalyst emerges as a convenient and efficient alternative for the synthesis of asymmetric biaryls. [ABSTRACT FROM AUTHOR]

Reactive oxygen species (ROS) and oxidative stress accelerate cellular aging, but their impact on different tissues varies. The cornea, known for its robust antioxidant defense systems, is relatively resistant to age‐related diseases like cancer. However, the precise mechanisms by which the cornea maintains ROS homeostasis during aging remain unclear. Through comparative single‐cell transcriptomic analysis of the cornea and other tissues in young and old nonhuman primates, we identified that a ZNF281 coding transcriptomic program is specifically activated in cornea during aging. Further investigation revealed that ZNF281 forms a positive feedback loop with FOXO3 to sense elevated levels of ROS and mitigate their effects potentially by regulating the mitochondrial respiratory chain and superoxide dismutase (SOD) expression. Importantly, we observed that overexpression of ZNF281 in MSCs prevented cellular senescence. In summary, these findings open up possibilities for understanding tissue‐specific aging and developing new therapies targeting ROS damage. [ABSTRACT FROM AUTHOR]

Aiming at the limitations of the existing railway foreign object detection methods based on two-dimensional (2D) images, such as short detection distance, strong influence of environment and lack of distance information, we propose Rail-PillarNet, a three-dimensional (3D) LIDAR (Light Detection and Ranging) railway foreign object detection method based on the improvement of PointPillars. Firstly, the parallel attention pillar encoder (PAPE) is designed to fully extract the features of the pillars and alleviate the problem of local fine-grained information loss in PointPillars pillars encoder. Secondly, a fine backbone network is designed to improve the feature extraction capability of the network by combining the coding characteristics of LIDAR point cloud feature and residual structure. Finally, the initial weight parameters of the model were optimised by the transfer learning training method to further improve accuracy. The experimental results on the OSDaR23 dataset show that the average accuracy of Rail-PillarNet reaches 58.51%, which is higher than most mainstream models, and the number of parameters is 5.49 M. Compared with PointPillars, the accuracy of each target is improved by 10.94%, 3.53%, 16.96% and 19.90%, respectively, and the number of parameters only increases by 0.64 M, which achieves a balance between the number of parameters and accuracy. [ABSTRACT FROM AUTHOR]