Well-defined 4-arm star block copolymer nanospheres of poly( N -isopropylacrylamide)- block -polystyrene 4 (PNIPAM- b -PS) 4 containing a hydrophobic core of the polystyrene (PS) block and a ...thermoresponsive corona of the 4-arm star poly( N -isopropylacrylamide) (PNIPAM) were prepared by dispersion RAFT polymerization employing a tetrafunctional macro-RAFT agent of tetra(trithiocarbonate)-terminated poly( N -isopropylacrylamide) (PNIPAM-TTC) 4 . The size of the 4-arm star (PNIPAM- b -PS) 4 nanospheres increases with the increasing degree of polymerization (DP) of the PS block, whereas it decreases with the DP of the star PNIPAM increasing. A comparison between the 4-arm star (PNIPAM- b -PS) 4 nanospheres and the linear poly( N -isopropylacrylamide)- block -polystyrene (PNIPAM- b -PS) nanospheres is made. It is found that the 4-arm star (PNIPAM- b -PS) 4 nanospheres and the linear PNIPAM- b -PS nanospheres have a similar particle size when the DPs of the PS and PNIPAM blocks in the star and linear block copolymers are close to each other. Interestingly, the topology of PNIPAM is found to exert influence on its thermo-responsive phase transition, and the (PNIPAM 122 - b -PS 110 ) 4 4-arm star block copolymer nanospheres have a lower critical solution temperature (LCST) lower than the PNIPAM 118 - b -PS 125 linear block copolymer nanospheres. At temperatures above LCST of the (PNIPAM 122 - b -PS 110 ) 4 nanospheres, the 4-arm star PNIPAM chains deposit on the PS core to form raspberry-like nanospheres, in which the dehydrated 4-arm star PNIPAM chains form dispersed microdomains on the PS core. This synthesis of (AB) 4 4-arm star block copolymer nano-assemblies is believed to be efficient and is helpful to study how the topology of PNIPAM affects the thermoresponsive phase transition.
Evidence has revealed the involvement of microRNAs (miRNAs) in modulating osteogenic differentiation, implying the promise of miRNA-based therapies for treating osteoporosis. This study investigated ...whether miR-181a-5p influences osteogenic differentiation and bone formation and aimed to establish the mechanisms in depth.
Clinical serum samples were obtained from osteoporosis patients, and MC3T3-E1 cells were treated with osteogenic induction medium (OIM) to induce osteogenic differentiation. miR-181a-5p-, Runt-related transcription factor 1 (Runx1)-, and/or allograft inflammatory factor-1 (AIF-1)-associated oligonucleotides or vectors were transfected into MC3T3-E1 cells to explore their function in relation to the number of calcified nodules, alkaline phosphatase (ALP) staining and activity, expression levels of osteogenesis-related proteins, and apoptosis. Luciferase activity, RNA immunoprecipitation, and chromatin immunoprecipitation assays were employed to validate the binding relationship between miR-181a-5p and Runx1, and the transcriptional regulatory relationship between Runx1 and AIF-1. Ovariectomy (OVX)-induced mice were injected with a miR-181a-5p antagonist for in vivo verification.
miR-181a-5p was highly expressed in the serum of osteoporosis patients. OIM treatment decreased miR-181a-5p and AIF-1 expression, but promoted Runx1 expression in MC3T-E1 cells. Meanwhile, upregulated miR-181a-5p suppressed OIM-induced increases in calcified nodules, ALP content, and osteogenesis-related protein expression. Mechanically, miR-181a-5p targeted Runx1, which acted as a transcription factor to negatively modulate AIF-1 expression. Downregulated Runx1 suppressed the miR-181a-5p inhibitor-mediated promotion of osteogenic differentiation, and downregulated AIF-1 reversed the miR-181a-5p mimic-induced inhibition of osteogenic differentiation. Tail vein injection of a miR-181a-5p antagonist induced bone formation in OVX-induced osteoporotic mice.
In conclusion, miR-181a-5p affects osteogenic differentiation and bone formation partially via the modulation of the Runx1/AIF-1 axis.
Increasing evidence suggests that disorders of inflammation, oxidative stress, and autophagy contribute to the pathogenesis of diabetic kidney disease (DKD). This study attempted to clarify the ...effect of allograft inflammatory factor-1 (AIF-1), miR-34a, and ATG4B on inflammation, oxidative stress, and autophagy in DKD both in vitro and in vivo experiments. In vivo, it was found that the levels of AIF-1, miR-34a, oxidative stress, and inflammatory factors were significantly increased in blood and urine samples of DKD patients and mouse models and correlated with the level of urinary protein. In vitro, it was also found that the expressions of AIF-1, miR-34a, ROS, and inflammatory factors were increased, while ATG4B and other autophagy related proteins were decreased in human renal glomerular endothelial cells (HRGECs) cultured with high concentration glucose medium (30 mmol/L). When AIF-1 gene was overexpressed, the levels of miR-34a, ROS, and inflammatory factors were significantly upregulated, and autophagy-related proteins such as ATG4B were downregulated, while downregulation of AIF-1 gene had the opposite effect. In addition, miR-34a inhibited the expression of ATG4B and autophagy-related proteins and increased the levels of ROS and inflammation. Furthermore, the result of luciferase reporter assay suggested that ATG4B was the target gene of miR-34a. When ATG4B gene was overexpressed, the level of autophagy was upregulated, and inflammatory factors were downregulated. Conversely, when ATG4B gene was inhibited, the level of autophagy was downregulated, and inflammatory factors were upregulated. Then, autophagy inducers inhibited the levels of inflammation and ROS, whereas autophagy inhibitors had the opposite function in HRGECs induced by glucose (30 mmol/L). In conclusion, the above data suggested that AIF-1 regulated the levels of inflammation, oxidative stress, and autophagy in HRGECs via miR-34a/ATG4B pathway to contribute to the pathogenesis of diabetic kidney disease.
Increasing evidence suggests that aldosterone (Aldo) plays an essential role in vascular calcification which is a serious threat to cardiovascular disease (CVD) developed from chronic kidney disease ...(CKD). However, the exact pathogenesis of vascular calcification is still unclear. First, we established CKD-associated vascular calcification mice model and knockout mice model to investigate the causal relationship between allograft inflammatory factor 1 (AIF-1) and vascular calcification. Then, endothelial cells (ECs) and vascular smooth muscle cells (VSMCs) co-culture experiments were performed to further explore the mechanisms of calcification. The results of the Aldo intervention mice model and transgenic mice model showed that Aldo could cause calcification by increasing the AIF-1 level. The results of
in vitro
co-culture model of ECs and VSMCs showed that AIF-1 silence in ECs may alleviate Aldo-induced calcification of VSMCs. In conclusion, our study indicated that Aldo may induce vascular calcification related to chronic renal failure
via
the AIF-1 pathway which may provide a potential therapeutic target.
Abstract Vascular calcification is a strong independent predictor of increased cardiovascular morbidity and mortality and has a high prevalence among patients with chronic kidney disease. The present ...study investigated the effects of quercetin on vascular calcification caused by oxidative stress and abnormal mitochondrial dynamics both in vitro and in vivo . Calcifying vascular smooth muscle cells (VSMCs) treated with inorganic phosphate (Pi) exhibited mitochondrial dysfunction, as demonstrated by decreased mitochondrial potential and ATP production. Disruption of mitochondrial structural integrity was also observed in a rat model of adenine-induced aortic calcification. Increased production of reactive oxygen species, enhanced expression and phosphorylation of Drp1, and excessive mitochondrial fragmentation were also observed in Pi-treated VSMCs. These effects were accompanied by mitochondria-dependent apoptotic events, including release of cytochrome c from the mitochondria into the cytosol and subsequent activation of caspase-3. Quercetin was shown to block Pi-induced apoptosis and calcification of VSMCs by inhibiting oxidative stress and decreasing mitochondrial fission by inhibiting the expression and phosphorylation of Drp1. Quercetin also significantly ameliorated adenine-induced aortic calcification in rats. In summary, our findings suggest that quercetin attenuates calcification by reducing apoptosis of VSMCs by blocking oxidative stress and inhibiting mitochondrial fission.
A dielectric liquid microlens array (LMA) with a tunable focal length was fabricated by using a microdroplet array generated through the dip-coating method. The process began with treating the ...octadecyltrichlorosilane (OTS) layer with selective UV/O3 irradiation for 20 min to establish a hydrophilic–hydrophobic patterning surface. The substrate was subsequently immersed in glycerol and then withdrawn at a constant rate to create a microdroplet array. Upon filling the cell with matching oil (SL5267) and placing it within a square array of a 200 μm diameter glycerol microdroplet array, the LMA was produced. The focal length ranged from approximately −0.96 to −0.3 mm within a voltage range of 0 to 60 Vrms. The glycerol microdroplets, characterized by their shapes, sizes, curvatures, and filling factors, can be precisely controlled by designing an OTS patterning or adjusting the dip-coating speed. This approach offers a rapid and high-throughput method for preparation. Our approach to fabricating tunable LMA offers several advantages, including simplicity of fabrication, uniform structural properties, cost-effectiveness, polarization independence, and excellent optical performance. These focus-tunable LMAs hold significant potential for applications in image processing, 3D displays, medical endoscopy, and military technologies.
•Trace ionic liquid doped PVC gels-based MLAs with tunable focal length.•The operating voltage for PVC/IL gel-based MLAs was nearly 1/22 of that required for MLAs created using undoped PVC gels.•The ...extent of focal length variation can be expanded by augmenting the film thickness.
Electrically responsive polyvinyl chloride (PVC) gels represent promising candidates for fabricating lenses with adjustable focal lengths. However, their practical use has been hampered by the elevated voltage requirements. In order to lower the driving voltage of PVC gels-based microlens array (MLA), trace ionic liquid (IL) −1-butyl-3-methylimidazole hexafluorophosphate (BMIMPF6) was doped. We employed a ring-array patterned electrode for the fabrication of PVC gels-based microlens arrays (MLAs). Our investigation revealed that the operating voltage for PVC gels-based MLAs doped with 0.01 wt% BMIMPF6 was nearly 1/22 of that required for MLAs created using undoped PVC gels. In the case of a microlens featuring a 250 μm aperture, the focal length varies from 4.2 mm to 2.5 mm as the voltage ranges from 5 V to 7 V. Importantly, this voltage range remains below the established safe limit for human exposure and obviates the need for intricate circuitry during manufacturing. Moreover, the extent of focal length variation can be expanded by augmenting the film thickness. Our approach offers valuable technical support for advancing the practical applications of PVC gel-based MLAs.
Background: Evidence has revealed the involvement of microRNAs (miRNAs) in modulating osteogenic differentiation, implying the promise of miRNA-based therapies for treating osteoporosis. This study ...investigated whether miR-181a-5p influences osteogenic differentiation and bone formation and aimed to establish the mechanisms in depth.
Methods: Clinical serum samples were obtained from osteoporosis patients, and MC3T3-E1 cells were treated with osteogenic induction medium (OIM) to induce osteogenic differentiation. miR-181a-5p-, Runt-related transcription factor 1 (Runx1)-, and/or allograft inflammatory factor-1 (AIF-1)-associated oligonucleotides or vectors were transfected into MC3T3-E1 cells to explore their function in relation to the number of calcified nodules, alkaline phosphatase (ALP) staining and activity, expression levels of osteogenesis-related proteins, and apoptosis. Luciferase activity, RNA immunoprecipitation, and chromatin immunoprecipitation assays were employed to validate the binding relationship between miR-181a-5p and Runx1, and the transcriptional regulatory relationship between Runx1 and AIF-1. Ovariectomy (OVX)-induced mice were injected with a miR-181a-5p antagonist for in vivo verification.
Results: miR-181a-5p was highly expressed in the serum of osteoporosis patients. OIM treatment decreased miR-181a-5p and AIF-1 expression, but promoted Runx1 expression in MC3T-E1 cells. Meanwhile, upregulated miR-181a-5p suppressed OIM-induced increases in calcified nodules, ALP content, and osteogenesis-related protein expression. Mechanically, miR-181a-5p targeted Runx1, which acted as a transcription factor to negatively modulate AIF-1 expression. Downregulated Runx1 suppressed the miR-181a-5p inhibitor-mediated promotion of osteogenic differentiation, and downregulated AIF-1 reversed the miR-181a-5p mimic-induced inhibition of osteogenic differentiation. Tail vein injection of a miR-181a-5p antagonist induced bone formation in OVX-induced osteoporotic mice.
Conclusion: In conclusion, miR-181a-5p affects osteogenic differentiation and bone formation partially via the modulation of the Runx1/AIF-1 axis.
Long cycle life and high energy/power density are imperative to energy storage systems. Polyaniline (PANI) has shown great potential as an electrode material but is limited by poor cycling and rate ...performance. We present a molecular design approach of binding short-chain aniline trimers (ATs) and carbon nanotubes (CNTs) through the formation of amide covalent linkages enabled by a simple laser scribing technique. The covalently coupled AT/CNT (cc-AT/CNT) composite retains 80% of its original capacitance after 20 000 charge/discharge cycles, which readily outperforms long-chain PANI/CNT composites without covalent connections. The compact AT/CNT heterointerfaces produce fast charge/discharge kinetics and excellent rate capability. The flexible symmetric quasi-solid-state devices can be stably cycled beyond 50 000 cycles, at least 5 times longer than most PANI/CNT-based symmetric supercapacitors reported to date. This molecular design of durable conducting polymer-based electrode materials enabled by laser irradiation presents a feasible approach toward robust advanced energy storage devices.
Long cycle life and high energy/power density are imperative to electrochemical energy storage systems. Conducting polymers like polyaniline have shown great potential as electroactive electrode ...materials but are limited by poor cycling and rate performance. To address these challenges, we have developed molecular engineering approaches to construct advanced conducting polymer hybrid materials for high-performance supercapacitors. One approach is enabled by the formation of covalent linkages between a 3D graphene network and short-chain conducting polymers built through azide click chemistry. An ultralong cycle life can be achieved by the designed electrode material while the capacitance can be further boosted using a redox-active electrolyte. We further seek to develop a scalable, effortless, and cost-efficient approach toward the fabrication of conducting polymer-based electrodes to reduce the time/energy consumption associated with conventional high-temperature synthetic methods. A simple one-step laser-induced stabilization of aniline oligomers on carbon nanotubes is established through amide covalent coupling. By taking advantage of the short-chain conducting polymers and the covalent connections, the designed electrode exhibits remarkable cycling stability and good rate capability. To further understand the capacitance degradation mechanisms of aniline oligomer-based materials during long-term cycling, two composite electrodes based on aniline trimers and carbon nanotubes are studied as model systems and are systematically investigated at both pre-cycling and post-cycling states through physicochemical and electrochemical characterizations. Furthermore, a promising nanocomposite based on an interpenetrating network of polyaniline and lignosulfonate has been designed as a waste-to-wealth approach to improve the supercapacitive performance of polyaniline. Additionally, a facile and green electrosynthesis approach is presented to fabricate a polydopamine nanofilm supported on oxygen-functionalized carbon cloth, which delivers high energy density and outstanding cycling stability. These studies present effective molecular design and facile fabrication approaches toward next-generation flexible, robust, and sustainable energy storage devices.
