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•A type of nanocomposite microgels with nanofibrous structure were prepared to treat osteochondral defects.•The microgels are biocompatible, biodegradable, and are ideal carriers for ...cells and transforming growth factor.•The microgels with and without loading transforming growth factor are combined to repair osteochondral defects in rats.•The multifunctional microgels achieved simultaneous repair of cartilage and subchondral bone in the osteochondral defects.
Treatment of osteochondral (OC) defects is still an immense challenge in clinic due to lack of satisfactory strategy to simultaneously regenerate both cartilage and subchondral bone. Herein, we propose an effective bottom-up strategy by developing a type of multifunctional chitosan-based nanocomposite microgels as the building blocks to repair OC defects. The microgels are biocompatible, and biodegradable, and have a hierarchical nanofibrous structure, mimicking the structural feature of extracellular matrix (ECM) to facilitate cell attachment and proliferation. Additionally, β-tricalcium phosphate (β-TCP) nanoparticles are incorporated in the microgels not only to promote the osteogenic differentiation of bone marrow mesenchymal stem cells (BMSCs), but also to facilitate the loading of transforming growth factor beta 1 (TGF-β1). For reconstructing OC defects, pure microgels are implanted at the bottom layer of the OC defects in rat knee joints to promote osteogenesis, while the microgels loaded with TGF-β1 are implanted at the top layer of the OC defects to promote cartilage regeneration. This modular microgel system results in simultaneous regeneration of cartilage and subchondral bone in OC defects, which is expected as a promising way for repairing other complex tissue defects in the field of tissue engineering.
This study aimed to explore the potential effects of 8-week parents-accompanied swimming on the physical capacity and intelligence of preschool children in China. Thirty-six boys (mean age 3.56 ± ...0.27 years) were divided into three groups: the traditional physical exercise group (TP, n = 12), the accompanied swimming group (AS, n = 12) and the independent swimming group (IS, n = 12). Participants’ physical capacity was assessed before and after the intervention using the following indicators: height, weight, distance of tennis ball throw, standing long jump distance, time for the 10-meter shuttle run, time for a two-legged continuous jump, sit-and-reach distance, and time on the walking balance beam. Intelligence was assessed at three points: pre-test, mid-test after 4 weeks, and post-test. Data were analyzed using a two-way repeated measures ANOVA, Bonferroni test ( p < 0.05) and effect size. The time of the AS and IS groups to walk the balance beam was significantly lower than the TP group, with a difference of 1.81 s ( p < 0.01, 95% CI −3.22 to −0.40, ES = 1.53) and 1.25 s ( p < 0.05, 95% CI −2.66 to 0.16, ES = 0.81). At the mid-test, the IQ scores of the TP group were lower than the AS group ( p < 0.05, 95% CI −12.45 to −0.96, ES = 0.89). Additionally, at post-test, the IQ scores of the TP group were significantly lower than those of both AS ( p < 0.01, 95% CI −14.12 to −2.74, ES = 1.15) and IS groups ( p < 0.01, 95% CI −12.53 to −3.31, ES = 1.21). Swimming enhances children’s balance and IQ scores more than traditional physical exercises. Involving parents in swimming leads to a more significant increase in IQ scores within 4 weeks of initial swimming exercise.
In efforts to enhance the activity of liposomal drugs against solid tumors, three novel lipids that carry imidazole-based headgroups of incremental basicity were prepared and incorporated into the ...membrane of PEGylated liposomes containing doxorubicin (DOX) to render pH-sensitive convertible liposomes (ICL). The imidazole lipids were designed to protonate and cluster with negatively charged phosphatidylethanolamine-polyethylene glycol when pH drops from 7.4 to 6.0, thereby triggering ICL in acidic tumor interstitium. Upon the drop of pH, ICL gained more positive surface charges, displayed lipid phase separation in TEM and DSC, and aggregated with cell membrane-mimetic model liposomes. The drop of pH also enhanced DOX release from ICL consisting of one of the imidazole lipids,
-2-((2,3-dihexadecyloxypropyl)thio)-5-methyl-1H-imidazole. ICL demonstrated superior activities against monolayer cells and several 3D MCS than the analogous PEGylated, pH-insensitive liposomes containing DOX, which serves as a control and clinical benchmark. The presence of cholesterol in ICL enhanced their colloidal stability but diminished their pH-sensitivity. ICL with the most basic imidazole lipid showed the highest activity in monolayer Hela cells; ICL with the imidazole lipid of medium basicity showed the highest anticancer activity in 3D MCS. ICL that balances the needs of tissue penetration, cell-binding, and drug release would yield optimal activity against solid tumors.
It is of great significance to explore the flow velocity characteristics of piped cars when they are started under different loads. In this paper, the flow velocity characteristics of the water flow ...around a piped car when it is started in the straight pipe section are studied through physical experiments. The masses of the piped cars are 1.5 kg, 1.9 kg, and 2.3 kg, respectively. The results show that, with the increase in the load of the pipeline car, the axial flow velocity in the front section increases, the absolute values of radial flow velocity and circumferential flow velocity increase, and the gradient of flow velocity increases. The positive radial flow velocity and negative circumferential flow velocity regions increase, and the distribution of positive and negative radial flow velocities and circumferential flow velocities is obvious. The gradients of axial, radial, and circumferential flow velocities in the annular section all increase, and the contour spacing becomes smaller and more densely distributed. The absolute values of the radial and circumferential flow velocities increase. The regional demarcation of axial flow velocity in the rear section is more obvious, and the average value of axial flow velocity in the high-flow-velocity area behind the vehicle increases. Additionally, the gradient of flow velocity increases. The absolute values of radial velocity and circumferential velocity increase, the gradient of velocity increases, and the velocity distribution is obviously regional. This study supplements and improves the theoretical study of a piped car when it is started and has certain reference value for the research and application of the hydraulic transport technology of the barrel-loading pipeline.
Introduction:
Geotechnical engineering disasters often result from instability failures in layered and heterogeneous fissured rock masses. However, the key mechanisms governing mechanical properties ...and crack propagation in these rock masses remain unclear.
Methods:
This study presents triaxial compression tests on double-layer rock-like specimens composed of limestone and sandstone materials, containing a single fissure, to investigate the effects of fissure angles and positions on the strength and failure modes of these double-layer specimens under varying confining pressure.
Results and Discussion:
The experimental results reveal that the intact composite rock approaches the strength of sandstone but is deformation-limited by limestone. Under constant confining pressure (
σ
3
= 5 MPa), the fissure angle affects initial crack initiation, and fissure position dictates the failure mode and extent, while increased confining pressure induces overall shear failure in the composite rock, with the failure mode being predominantly influenced by confining pressure. Concerning mechanical deformation, augmenting the fissure angle and confining pressure substantially enhances the elasticity and ductility of the composite rock. Regarding volumetric deformation, the extent of volume shrinkage in the composite rock is influenced by both fissure angle and confining pressure, while volume expansion is influenced by fissure position. Under uniaxial compression, fissured composite rock exhibits the most unstable crack propagation, resulting in early failure. Triaxial compression shows that a higher fissure angle stabilizes crack propagation while confining pressure variation affects stability only when the fissure is in limestone. When the fissure is in sandstone, crack propagation stability remains at its highest. Furthermore, an increase in fissure angle, higher confining pressure, and changes in fissure position from sandstone through the contact interface to limestone contribute to an increasing trend in the peak strength and elastic modulus of the composite rock. Fissure-induced rock degradation is primarily influenced by the fissure angle. These findings are significant for guiding engineering construction and design, providing valuable insights to geotechnical engineers, and enhancing safety in rock engineering projects.
Inflammatory bowel disease (IBD) is a group of recurrent chronic inflammatory diseases, including Crohn’s disease (CD) and ulcerative colitis (UC). Although IBD has been extensively studied for ...decades, its cause and pathogenesis remain unclear. Existing research suggests that IBD may be the result of an interaction between genetic factors, environmental factors and the gut microbiome. IBD is closely related to non-coding RNAs (ncRNAs). NcRNAs are composed of microRNA(miRNA), long non-coding RNA(lnc RNA) and circular RNA(circ RNA). Compared with miRNA, the role of lnc RNA in IBD has been little studied. Lnc RNA is an RNA molecule that regulates gene expression and regulates a variety of molecular pathways involved in the pathbiology of IBD. Targeting IBD-associated lnc RNAs may promote personalized treatment of IBD and have therapeutic value for IBD patients. Therefore, this review summarized the effects of lnc RNA on the intestinal epithelial barrier, inflammatory response and immune homeostasis in IBD, and summarized the potential of lnc RNA as a biomarker of IBD and as a predictor of therapeutic response to IBD in the future.
Reactive distillation is a process intensification technology that combines a chemical reaction with distillation in a device. Enzymatic Reactive Distillation (ERD)-the application of immobilized ...enzyme catalysts instead of traditional acid-base catalysts in reactive distillation has attracted much attention due to its high selectivity and mild process conditions. However, to apply ERD to industrial processes, it is critical to address constraints such as the cost and stability of immobilized enzyme catalysts. Herein, in this paper,
Candida antarctica
lipase B (CALB) was immobilized in a commercial resin "NKA" by a hydrophobic interaction, and the immobilized enzyme was PEGylated by a series reaction. Both the stability and catalytic performance of the prepared NKA-CALB-PEGylated are significantly improved. The catalytic efficiency of NKA-CALB-PEGylated (80.1%) in the transesterification reaction system is slightly higher than those of NKA-CALB (71.7%) and Novozyme435 (69.3%), and significantly higher than that of Sol gel-CALB (60%) published in our previous literature. Additionally, NKA-CALB-PEGylated retained an initial activity of 92.4% after repeated use six times, which was significantly higher than those of Novozyme435 (60.2%) and NKA-CALB (78.6%). Therefore, the prepared stable and economical enzyme catalyst has great prospects for applications in the ERD industry.
A novel enzyme catalyst with excellent stability and catalytic efficiency expected to be used in the ERD industry was prepared.
Purpose
Optical coherence tomography angiography (OCT-A) is a novel imaging modality for the diagnosis of chorioretinal diseases. A number of FDA-approved OCT-A devices are currently commercially ...available, each with unique algorithms and scanning protocols. Although several published studies have compared different combinations of OCT-A machines, there is a lack of agreement on the consistency of measurements across OCT-A devices. Therefore, we conducted a prospective quantitative comparison of four available OCT-A platforms.
Methods
Subjects were scanned on four devices: Optovue RTVue-XR, Heidelberg Spectralis OCT2 module, Zeiss Plex Elite 9000 Swept-Source OCT, and Topcon DRI-OCT Triton Swept-Source OCT. 3 mm × 3 mm images were utilized for analysis. Foveal avascular zone (FAZ) area was separately and independently measured by two investigators. Fractal dimension (FD), superficial capillary plexus (SCP), and deep capillary plexus (DCP) vessel densities (VD) were calculated from binarized images using the Fiji image processing software. SCP and DCP VD were further calculated after images were skeletonized. Repeated measures ANOVA, post hoc tests, and interclass correlation coefficient (ICC) were performed for statistical analysis.
Results
Sixteen healthy eyes from sixteen patients were scanned on the four devices. Images of five eyes from the Triton device were excluded due to poor image quality; thus, the authors performed two sets comparisons, one with and one without the Triton machine. FAZ area showed no significant difference across devices with an ICC of > 95%. However, there were statistically significant differences for SCP and DCP VD both before and after skeletonization (
p
< 0.05). Fractal analysis revealed no significant difference of FD at the SCP; however, a statistically significant difference was found for FD at the DCP layer (
p
< 0.05).
Conclusions
The results showed that FAZ measurements were consistent across all four devices, while significant differences in VD and FD measurements existed. Therefore, we suggest that for both clinical follow-up and research studies, FAZ area is a useful parameter for OCT-A image analysis when measurements are made on different machines, while VD and FD show significant variability when measured across devices.
Disturbances in maternal lipid metabolism may increase the risk of developing pregnancy complications and adverse perinatal outcomes. However, there is no consensus as to what constitutes normal ...serum lipid ranges during pregnancy. Our study was aimed to establish trimester-specific serum lipid reference intervals (RIs) and investigate the associations between maternal dyslipidaemia and adverse outcomes in a population-based study.
The first- and third-trimester lipid profiles were derived from 16,489 singlet pregnant women for regular antenatal check-ups between 2017 and 2019. The serum samples were assayed for total cholesterol (TC), triglycerides (TG), high-density lipoprotein-cholesterol (HDL-C), and low-density lipoprotein-cholesterol (LDL-C) in the institutional clinical laboratory. The trimester-specific lipid RIs were estimated with both of the direct observational and the indirect Hoffmann methods. The associations between maternal lipid profiling and pregnancy complications and perinatal outcomes were assessed statistically.
Serum levels of TC, TG, LDL-C and HDL-C were all increased significantly in the third trimester of pregnancy. There was no significant difference between the observed RIs established with healthy pregnant women and the calculated RIs derived from the Hoffmann method. A trend towards increased risks of gestational complications and adverse perinatal outcomes was observed in the subjects with elevated levels of TC, TG, and LDL-C or decreased level of HDL-C.
In pregnancy, increased serum levels of TC, TG and LDL-C, and a decreased level of HDL-C posed higher risks of developing pregnancy complications and adverse perinatal outcomes.
Key messages
It is necessary to establish trimester-specific reference intervals for serum lipids including TC, TG, LDL-C and HDL-C that were found significantly increased as the gestational age went up. More importantly, around the upper reference limits of TC, TG and LDL-C (or the lower reference limit of HDL-C), the higher the serum lipid levels were (or the lower the HDL-C level was), the higher risks of developing pregnancy complications and adverse perinatal outcomes were observed.
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