Oxidative phosphorylation is a pivotal therapeutic target of fibrodysplasia ossificans progressiva.

Heterotopic ossification (HO) is a non-physiological bone formation where soft tissue progenitor cells differentiate into chondrogenic cells. In fibrodysplasia ossificans progressiva (FOP), a rare genetic disease characterized by progressive and systemic HO, the Activin A/mutated ACVR1/mTORC1 cascade induces HO in progenitors in muscle tissues. The relevant biological processes aberrantly regulated by activated mTORC1 remain unclear, however. RNA-sequencing analyses revealed the enrichment of genes involved in oxidative phosphorylation (OXPHOS) during Activin A-induced chondrogenesis of mesenchymal stem cells derived from FOP patient-specific induced pluripotent stem cells. Functional analyses showed a metabolic transition from glycolysis to OXPHOS during chondrogenesis, along with increased mitochondrial biogenesis. mTORC1 inhibition by rapamycin suppressed OXPHOS, whereas OXPHOS inhibitor IACS-010759 inhibited cartilage matrix formation in vitro, indicating that OXPHOS is principally involved in mTORC1-induced chondrogenesis. Furthermore, IACS-010759 inhibited the muscle injury-induced enrichment of fibro/adipogenic progenitor genes and HO in transgenic mice carrying the mutated human ACVR1. These data indicated that OXPHOS is a critical downstream mediator of mTORC1 signaling in chondrogenesis and therefore is a potential FOP therapeutic target.

Efficient adsorption of radioactive iodine by covalent organic framework/chitosan aerogel.

Radioactive iodine is considered one of the most dangerous radioactive elements in nuclear waste. Therefore, effective capture of radioactive iodine is essential for developing and using nuclear energy to solve the energy crisis. Some materials that have been developed for removing radioactive iodine still suffer from complex synthesis, low removal capacity, and non-reusability. Herein, covalent organic framework (COF)/chitosan (CS) aerogels were prepared using vacuum freeze-drying, and the COF nanoparticles were tightly attached on the green biomass material CS networks. Due to the synergistic effect of both COF and CS, the composite aerogel shows a three-dimensional porous and stable structure in the recycle usage. The COF/CS aerogel exhibits excellent iodine adsorption capacity of 2211.58 mg g-1 and 5.62 g g-1 for static iodine solution and iodine vapor, respectively, better than some common adsorbents. Furthermore, COF/CS aerogel demonstrated good recyclability performance with 87 % of the initial adsorption capacity after 5 cycles. In addition, the interaction between iodine and imine groups, amino groups, and benzene rings of aerogel are the possible adsorption mechanisms. COF/CS aerogel has excellent adsorption properties, good chemical stability, and reusable performance, which is a potential and efficient adsorbent for industrial radioactive iodine adsorption from nuclear waste.

High-efficient removal of anionic dye from aqueous solution using metal-organic frameworks@chitosan aerogel rich in benzene structure.

With the exponentially increase of dye pollutants, the purification of dye wastewater has been an urgent ecological problem. As a novel type of porous adsorbent, metal-organic frameworks still face challenges in recyclability, agglomeration, and environmentally unfriendly synthesis. Herein, MOF-525 was in-situ growth onto the surface of the chitosan (CS) beads to fabricate MOF-525@CS aerogel. CS was utilized as substrate to uniformly disperse MOF-525, thereby significantly mitigating agglomeration and improving recyclability of MOF-525. The characterization results shown that MOF-525@CS aerogel had a high specific surface area of 103.0 m2·g-1, and MOF-525 was uniformly distributed in the 3D porous structure of CS, and the presence of benzoic acid was detected. The MOF-525@CS aerogel had a remarkable adsorption capacity of 1947 mg·g-1 for Congo red, which is greater than the sum of its parts. MOF-525@CS aerogel also inherited the rapid adsorption ability of MOF-525, removing 80 % of Congo red within 600 min. Such excellent adsorption performance can be attributed to the benzoic acid trapped by CS via CN band to enhance the π-π stacking interactions. Additionally, the utilization of benzoic acid makes the synthesis process of MOF-525@CS aerogel more environmentally friendly. The high-efficient MOF-525@CS aerogel is a competitive candidate for dye pollution adsorption.

Porous metal-organic framework-acrylamide-chitosan composite aerogels: Preparation, characterization and adsorption mechanism of azo anionic dyes adsorbed from water.

Micro- and nano-metal-organic frameworks with different adsorption properties were prepared by a time-modulation hydrothermal method. By comparing the adsorption properties, the most effective MIL-68(Fe)-12 was selected to be mixed with chitosan (CS), and porous metal-organic framework-acrylamide-chitosan composite aerogel (PMACA) was prepared by introducing acrylamide prior to glutaraldehyde crosslinking. The adsorption capacity of PMACA doped with acrylamide was as high as 2086.44 mg·g-1. The adsorption performance of PMACA was 1.48 times higher compared to the porous metal-organic framework-chitosan composite aerogel (PMCA) undoped with acrylamide. With the introduction of acrylamide, the stability of PMACA was improved, making it less prone to dispersion and decomposition. Structural characterization and adsorption properties were analyzed using methods such as XRD, FTIR, TGA, SEM, BET, and Zeta potential. The adsorption performance of PMACA was investigated further through batch tests with variables such as adsorbent dosage, pH, contact time, initial CR solution concentration, and temperature. The model fitting of PMACA was consistent with the pseudo-second-order model and the Sips model. The adsorption thermodynamics showed that high temperature promoted spontaneous adsorption behavior. PMACA showed a recovery rate of approximately 86 % after six cyclic adsorption tests. PMACA maintained a recovery rate of roughly 86 % after six cyclic adsorption tests. The combined effects of electrostatic attraction, hydrogen bonding, and π-π conjugation resulted in excellent adsorption performance, while pore filling also contributed to the efficient adsorption of Congo red (CR).

Green preparation of magnetic ferroferric oxide-polyvinyl alcohol-alginate coated UiO-67 nanospheres: Characterization, adsorption properties and adsorption mechanism of methylene blue.

In this paper, a kind of magnetic ferric oxide/polyvinyl alcohol/calcium alginate/UiO-67 (Fe3O4/PVA/CA/UiO-67) nanospheres with homogeneous surface interconnecting structures was prepared by using macromolecular polymer polyvinyl alcohol and sodium alginate as carriers and zirconium organic skeleton as nanocrystals. The properties of magnetic nanospheres were studied by SEM, FT-IR, TGA, XRD, BET, VSM and Zeta potential. The impression of diverse temperatures, MB concentrations, interaction time, pH, and magnetic aerogel sphere dose on MB removal was studied. The optimum adsorption temperature and pH of magnetic nanospheres for MB were 298 K, and 10, respectively. Langmuir simulated that the maximum removal of MB by magnetic nanospheres at room temperature (298 K) was 1371.8 mg/g. The removal of MB by magnetic nanospheres complied with the pseudo-first-order kinetic model. The isotherm simulation can infer that the Langmuir model was more comply with MB adsorption on magnetic aerogel spheres. Thermodynamic studies have confirmed that the removal of MB by magnetic nanospheres was exothermic and spontaneous. The interaction mechanism of MB on magnetic nanospheres can be deduced by FT-IR and BET, including hydrogen bond, π-π bond, electrostatic interaction, and mesoporous pore flow. The removal rate of nanospheres for MB still reached 70.06 % after six cycles.

Efficient adsorption of methylene blue in water by nitro-functionalized metal-organic skeleton­calcium alginate composite aerogel.

This paper presents the first investigation of the adsorption performance of methylene blue by the nitro-functionalized metal-organic framework (MIL-88B-NO2). MIL-88B-NO2 has a specific surface area of 836.0 m2/g, which is 109.8 % higher than MIL-88B. The maximum adsorption capacity of methylene blue is 383.6 mg/g, which is 68.2 % higher than that of MIL-88B. This phenomenon can be attributed to the great increase in specific surface area and the introduction of nitro-functional groups. However, its microcrystalline nature makes it difficult to remove in practical applications and quickly causes secondary pollution. Therefore, the composite of MIL-88B-NO2 and calcium alginate (CA) to form aerogel maintains the inherent properties of the two materials and makes it easy to recycle. The utmost adsorption capability of MIL-88B-NO2/CA-2 aerogel is 721.0 mg/g. Compared with MIL-88B-NO2, the adsorption performance of MIL-88B-NO2/CA-2 aerogel is further improved by 88.0 %. The higher adsorption capacity of the adsorbent may be due to the synergistic interplay of electrostatic attraction, π-π conjugation, hydrogen bonding, metal coordination effect, and physicochemical properties. Also, MIL-88B-NO2/CA-2 aerogel has good recyclability, indicating that it has broad application prospects in the removal of positive dyes in contaminated water.

Efficient adsorption of azo anionic dye Congo Red by micro-nano metal-organic framework MIL-68(Fe) and MIL-68(Fe)/chitosan composite sponge: Preparation, characterization and adsorption performance.

Micro-nano metal-organic framework (MIL-68(Fe)) for efficient adsorption of azo anionic dye Congo red (CR) was successfully prepared by one-step hydrothermal method under acidic environment. And a MIL-68(Fe)/chitosan composite sponge (MIL-68(Fe)/CS) was prepared under the coating of chitosan (CS). After comparing the performance of MIL-68(Fe) and MIL-68(Fe)/CS, we focus on exploring MIL-68(Fe)/CS. It ensured the CR removal efficiency while reaching the adsorption equilibrium faster than MIL-68(Fe), and solved the defect that the powder was difficult to be stripped by water after adsorption. The physicochemical properties and surface morphology of the adsorbent were characterized by SEM, FTIR, XRD, TGA, BET, and Zeta potential. The effects of pH, contact time, adsorbent dosage, initial solution concentration and temperature on the adsorption performance of the adsorbent were systematically analyzed. The pseudo-second-order model and the Sips model were most consistent for the adsorption process, indicating that the adsorption process of MIL-68(Fe)/chitosan composite sponge on CR is a complex physicochemical process. The removal rates of CR by MIL-68(Fe) and MIL-68(Fe)/chitosan composite sponge reached the maximum values of 99.55 % and 99.51 % at 318 K, respectively. And the maximum adsorption capacity of CR by MIL-68(Fe)/chitosan composite sponge at 318 K was 1184.16 mg·g-1. After six cycles of adsorption and desorption, the removal rate of CR was still higher than 80 %. The synergistic effects of π-π stacking, electrostatic interactions, hydrogen bonding and pore filling have important effects on CR removal.

The Defects, Physicochemical Properties, and Surface Charge of MIL-88A (Al) Crystal Were Regulated for Highly Efficient Removal of Anionic Dyes: Preparation, Characterization, and Adsorption Mechanism.

In this paper, the physicochemical properties, surface charge, and crystal defects of MIL-88A (Al) were controlled by adjusting the ratio of metal ligands and temperature in the synthetic system without the addition of surfactants. The adsorption properties of different crystals for Congo red (CR) were studied. Among them, MIL-88A (Al)-130 and MIL-88A (Al)-d have the best adsorption properties. The maximum adsorption capacities are 600.8 and 1167 mg · g-1, respectively. Compared with MIL-88A (Al)-130, the adsorption performance of MIL-88A (Al)-d was increased by 94.2%, and the adsorption rate was increased by about 4 times. It can be seen that increasing the proportion of metal ligands within a certain range will improve the adsorption capacity. The structure and morphology of the adsorbent were characterized by XRD, FTIR, SEM, EDS, TGA, BET, and zeta potential. The effects of time, temperature, pH, initial solution concentration, and dosage on CR adsorption properties were systematically discussed. The pseudo-second-order kinetic model and Langmuir isothermal model can well describe the adsorption process, which indicates that the adsorption process is a single-layer chemisorption occurring on a uniform surface. According to thermodynamics, this adsorption is an endothermic process. The mechanism of CR removal is proposed as the electrostatic attraction, hydrogen bond, metal coordination effect, π-π conjugation, crystal defect, and pore-filling effect. In addition, MIL-88A (Al)-d has good repeatability, indicating that it is a good material for treating anionic dye wastewater.

Collagen X Is Dispensable for Hypertrophic Differentiation and Endochondral Ossification of Human iPSC-Derived Chondrocytes.

Collagen X is a non-fibril collagen produced by hypertrophic chondrocytes and was believed to associate with the calcification process of growth plate cartilage. The homozygous loss of Col10a1 gene in mice, however, demonstrated no remarkable effects on growth plate formation or skeletal development. To investigate the role of collagen X in human chondrocytes, we established human induced pluripotent stem cells (hiPSCs) with heterozygous (COL10A1 +/-) or homozygous (COL10A1 -/-) deletions of COL10A1 gene using the dual sgRNA CRISPR/Cas9 system. Several mutant clones were established and differentiated into hypertrophic chondrocytes by a previously reported 3D induction method. No remarkable differences were observed during the differentiation process between parental and mutant cell lines, which differentiated into cells with features of hypertrophic chondrocytes, indicating that collagen X is dispensable for the hypertrophic differentiation of human chondrocytes in vitro. To investigate the effects of collagen X deficiency in vivo, chondrocyte pellets at the proliferating or prehypertrophic stage were transplanted into immunodeficient mice. Proliferating pellet-derived tissues demonstrated the zonal distribution of chondrocytes with the transition to bone tissues mimicking growth plates, and the proportion of bone tended to be larger in COL10A1 -/- tissues. Prehypertrophic pellet-derived tissues produced trabecular bone structures with features of endochondral ossification, and there was no clear difference between parental- and mutant-derived tissues. A transcriptome analysis of chondrocyte pellets at the hypertrophic phase showed a lower expression of proliferating-phase genes and a higher expression of calcification-phase genes in COL10A1 -/- pellets compared with parental cell pellets. These in vitro and in vivo data suggested that collagen X is dispensable for the hypertrophic differentiation and endochondral ossification of human iPSC-derived chondrocytes, though it may facilitate the differentiation process. Thus, COL10A1 -/- iPSC lines are useful for investigating the physiological role of collagen X in chondrocyte differentiation. © 2023 The Authors. JBMR Plus published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research.

Simple synthesis of chitosan/alginate/graphene oxide/UiO-67 amphoteric aerogels: Characterization, adsorption mechanism and application for removal of cationic and anionic dyes from complex dye media.

A chitosan/alginate/graphene oxide/UiO-67 (CS/SA/GO/UiO-67) amphoteric aerogel was synthesized successfully. A series of characterization experiments of CS/SA/GO/UiO-67 amphoteric aerogel was performed by SEM, EDS, FT-IR, TGA, XRD, BET, and zeta potential. The competitive adsorption properties of different adsorbents for complex dyes wastewater (MB and CR) at room temperature (298 K) were compared. Langmuir isotherm model predicted that the maximum adsorption quantity of CS/SA/GO/UiO-67 for CR and MB was 1091.61 and 1313.95 mg/g, respectively. The optimum pH values of CS/SA/GO/UiO-67 for the adsorption of CR and MB were 5 and 10, respectively. The kinetic analysis showed that the adsorption of MB and CR on CS/SA/GO/UiO-67 was more suitable for the pseudo-second-order and pseudo-first-order kinetic model, respectively. The isotherm study revealed that the adsorption of MB and CR was consistent with the Langmuir isotherm model. The thermodynamic study demonstrated that the adsorption process of MB and CR was exothermic and spontaneous. FT-IR analysis and zeta potential characterization experiments revealed that the adsorption mechanism of MB and CR on CS/SA/GO/UiO-67 depended on π-π bond, hydrogen bond, and electrostatic attraction. Repeatable experiments showed that the removal rates of MB and CR of CS/SA/GO/UiO-67 after six cycles of adsorption were 67.19 and 60.82 %, respectively.

Unexpected Behavior in Thermal Conductivity of Confined Monolayer Water.

Monolayer water can be formed under extreme confinement and will present distinctive thermodynamic properties compared with bulk water. In this work, we perform molecular dynamics simulations to study the thermal conductivity of monolayer water confined in graphene channels, finding an unexpected way of thermal conductivity of monolayer water dependent on its number density, which has a close correlation with the structure of water. The monolayer water is in an amorphous state, and its thermal conductivity increases linearly with the area density when the water density is low at first. Then, the thermal conductivity increases as the number density of water rises, which is attributed to the formation of a crystal structure and the reduction of crystal defects as the number of water molecules increases. After reaching the zenith, the thermal conductivity decreases rapidly owing to the formation of a wrinkle structure of monolayer water with excessive water molecules, which weakens the phonon dispersion. Moreover, we further investigate the remarkable effects of the channel height on both the structure and thermal conductivity of monolayer water. In summary, this study demonstrates the close connection between the thermal conductivity of monolayer water and its structure, contributing to not only expanding the understanding of the thermodynamic property of nanoconfined water but also benefiting the engineering applications for nanofluidics.

Enhanced methylene blue adsorption using zirconate alginate/graphene oxide/UiO-67 aerogel spheres: Synthesis, characterization, kinetic studies, and adsorption mechanisms.

Zirconium alginate/graphene oxide (ZA/GO) hydrogel spheres were prepared by crosslinking sodium alginate and GO with Zr4+. Then Zr4+ on the surface of the ZA/GO substrate acted as the metal nucleation site of the UiO-67 crystal and interacted with the organic ligand biphenyl 4-4'-dicarboxylic acid (BPDC) to make UiO-67 grow in situ on the surface of the ZA/GO hydrogel sphere by the hydrothermal method. The BET surface areas of ZA/GO, ZA/UiO-67, and ZA/GO/UiO-67 aerogel spheres were 1.29, 47.71, and 89.33 m2/g respectively. The maximum adsorption capacities of ZA/GO, ZA/UiO-67, and ZA/GO/UiO-67 aerogel spheres for methylene blue (MB) at room temperature (298 K) were 145.08, 307.49, and 1105.23 mg/g respectively. The kinetic analysis showed that the adsorption process of MB on the ZA/GO/UiO-67 aerogel sphere was consistent with the pseudo-first-order kinetic model. Isotherm analysis showed that MB was adsorbed on ZA/GO/UiO-67 aerogel spheres as a single layer. Thermodynamic analysis showed that the adsorption process of MB on the ZA/GO/UiO-67 aerogel sphere was exothermic and spontaneous. Adsorption of MB on ZA/GO/UiO-67 aerogel spheres is mainly dependent on π-π bond, electrostatic interaction, and hydrogen bond. After 8 cycles, ZA/GO/UiO-67 aerogel spheres still showed high adsorption performance and good reuse ability.

Efficient adsorption of Congo red by micro/nano MIL-88A (Fe, Al, Fe-Al)/chitosan composite sponge: Preparation, characterization, and adsorption mechanism.

MIL-88A crystals with three different metal ligands (Fe, Al, FeAl) were prepared by hydrothermal method for the first time. The three materials' crystal structure and surface morphology are different, leading to different adsorption properties of Congo red (CR). The maximum adsorption capacities of MIL-88A (Fe), MIL-88A (FeAl), and MIL-88A (Al) are 607.7 mg · g-1, 536.4 mg · g-1, and 512.1 mg · g-1 respectively. In addition, MIL-88A was combined with chitosan (CS) respectively, and MIL-88A/CS composite sponge was prepared by the freeze-drying method, which not only solved the defect that MIL-88A powder was difficult to recover but also further improved the removal ability of CR by the adsorbent. The maximum adsorption capacities of MIL-88A (FeAl)/CS, MIL-88A (Fe)/CS, MIL-88A (Al)/CS, and CS are 1312 mg · g-1, 1056 mg · g-1, 996.7 mg · g-1, and 769.6 mg · g-1, respectively. The structure and physicochemical properties of the materials were analyzed by SEM, FTIR, XRD, TGA, BET, and Zeta. The adsorption process of CR follows pseudo-second-order kinetics and Langmuir, Sips isotherm model. Combined with thermodynamic parameters, the adsorption behavior was described as endothermic monomolecular chemical adsorption. The removal of CR is attributed to electrostatic interactions, hydrogen bonding, metal coordination effects, and size-matching effects.

3D osteogenic differentiation of human iPSCs reveals the role of TGFß signal in the transition from progenitors to osteoblasts and osteoblasts to osteocytes.

Although the formation of bone-like nodules is regarded as the differentiation process from stem cells to osteogenic cells, including osteoblasts and osteocytes, the precise biological events during nodule formation are unknown. Here we performed the osteogenic induction of human induced pluripotent stem cells using a three-dimensional (3D) culture system using type I collagen gel and a rapid induction method with retinoic acid. Confocal and time-lapse imaging revealed the osteogenic differentiation was initiated with vigorous focal proliferation followed by aggregation, from which cells invaded the gel. Invading cells changed their morphology and expressed osteocyte marker genes, suggesting the transition from osteoblasts to osteocytes. Single-cell RNA sequencing analysis revealed that 3D culture-induced cells with features of periosteal skeletal stem cells, some of which expressed TGFß-regulated osteoblast-related molecules. The role of TGFß signal was further analyzed in the transition from osteoblasts to osteocytes, which revealed that modulation of the TGFß signal changed the morphology and motility of cells isolated from the 3D culture, suggesting that the TGFß signal maintains the osteoblastic phenotype and the transition into osteocytes requires down-regulation of the TGFß signal.

Removal of Methylene Blue Dye from Aqueous Solutions by Pullulan Polysaccharide/Polyacrylamide/Activated Carbon Complex Hydrogel Adsorption.

In this study, composite hydrogels were prepared using a simple synthetic technique to adsorb methylene blue (MB) from water. The hydrogel comprised potassium persulfate (KPS) as the initiator, N,N'-methylene bisacrylamide as the crosslinking agent, and sodium hydroxide (NaOH) as the activator. It was employed to adsorb MB at different concentrations from water. The morphology and properties of PUL/PAM/GO composites were characterized through thermogravimetric analysis, Fourier transform infrared spectroscopy, and scanning electron microscopy. Moreover, the adsorption properties, adsorption isotherms, adsorption kinetics, adsorption thermodynamics, and swelling properties of the hydrogel for MB were investigated. The optimal ratio of PUL to AC was obtained as 6:1 by fixing the amount of PUL and loading AC of different masses. The maximum adsorption capacity was obtained as 591.4 mg/g. It also exhibited certain mechanical strength. The adsorption of MB conforms to pseudo-first-order kinetics and Langmuir isotherms. In this study, an environment-friendly, cheap, simple, and efficient way was presented for the composite hydrogel in the direction of water treatment.

Recapitulation of pro-inflammatory signature of monocytes with ACVR1A mutation using FOP patient-derived iPSCs.

BACKGROUND: Fibrodysplasia ossificans progressiva (FOP) is a rare genetic disease characterized by progressive heterotopic ossification (HO) in soft tissues due to a heterozygous mutation of the ACVR1A gene (FOP-ACVR1A), which erroneously transduces the BMP signal by Activin-A. Although inflammation is known to trigger HO in FOP, the role of FOP-ACVR1A on inflammatory cells remains to be elucidated. RESULTS: We generated immortalized monocytic cell lines from FOP-iPSCs (FOP-ML) and mutation rescued iPSCs (resFOP-ML). Cell morphology was evaluated during the monocyte induction and after immortalization. Fluorescence-activated cell sorting (FACS) was performed to evaluate the cell surface markers CD14 and CD16 on MLs. MLs were stimulated with lipopolysaccharide or Activin-A and the gene expression was evaluated by quantitative PCR and microarray analysis. Histological analysis was performed for HO tissue obtained from wild type mice and FOP-ACVR1A mice which conditionally express human mutant ACVR1A gene by doxycycline administration. Without any stimulation, FOP-ML showed the pro-inflammatory signature of CD16+ monocytes with an upregulation of INHBA gene, and treatment of resFOP-ML with Activin-A induced an expression profile mimicking that of FOP-ML at baseline. Treatment of FOP-ML with Activin-A further induced the inflammatory profile with an up-regulation of inflammation-associated genes, of which some, but not all, of which were suppressed by corticosteroid. Experiments using an inhibitor for TGFß or BMP signal demonstrated that Activin-A-induced genes such as CD16 and CCL7, were regulated by both signals, indicating Activin-A transduced dual signals in FOP-ML. A comparison with resFOP-ML identified several down-regulated genes in FOP-ML including LYVE-1, which is known to suppress matrix-formation in vivo. The down-regulation of LYVE-1 in HO tissues was confirmed in FOP model mice, verifying the significance of the in vitro experiments. CONCLUSION: These results indicate that FOP-ML faithfully recapitulated the phenotype of primary monocytes of FOP and the combination with resFOP-ML is a useful tool to investigate molecular events at the initial inflammation stage of HO in FOP.

Removal of Methylene Blue by Crosslinked Egg White Protein/Graphene Oxide Bionanocomposite Aerogels.

Egg white protein is a non-toxic and biodegradable biopolymer that forms a gel easily via simple thermal denaturation treatment. A novel aerogel on the basis of egg white protein crosslinked with graphene oxide was prepared via a facile freeze-drying method. The structure and physicochemical characteristics of the aerogels were characterized by scanning electron microscopy (SEM), Fourier transform infrared (FTIR) spectroscopy, thermogravimetric analysis (TGA) and Brunauer-Emmett-Teller (BET) analysis. The adsorption properties of the aerogels were investigated by studying the influencing factors such as the solution pH, dose, temperature and contact time. The adsorption capacity of methylene blue onto the aerogels was tested, whose maximum adsorption capacity, calculated by the Langmuir isotherm equation, reached 91.7 mg/g. Adsorption kinetics studies showed that the adsorption followed the pseudo-second-order kinetic model. Thermodynamic data implied that methylene blue adsorbed by the aerogels was an exothermic and spontaneous process.

Effects of visual search task on attentional bias and stress response under pressure.

BACKGROUND: it has always been a problem for athletes that their performance is out of order due to pressure in major competitions. The change of attention pattern and the emergence of stress response (SR) caused by negative affect (NA) are the direct reasons for the greater impact on the performance of athletes. It is a hot topic to explore how to improve attention bias (AB) and SR of athletes in stressful situations. OBJECTIVE: the study aimed to analyze the improvement effect of visual search task (VST) training on AB and SR of athletes under pressure situations. METHODS: 62 male basketball players with national level 2 or above of Shenyang sports institute were divided into experimental group (EG) and control group (CG). Visual search task training program was used in the EG (happy, sad, disgusted, neutral faces) and sham training program was used in the CG (all faces with neutral expression) for two months. Under the stress situation, attention behavior of all subjects before and after training was tested. Physiological coherence and autonomic balance system were used to record heart rate variability synchronously. Parallel frequency domain analysis was divided into very low frequency band (VLF), low frequency (LF), high frequency (HF) and total spectrum (TP). The normalized treatment obtained indexes such as HFnorm, LFnorm, and LF/HF. The e-prime 2.0 software was adopted to obtain the attention bias score. The Positive and Negative Affect Scale (PANAS) and the self-rating stress scale were adopted for evaluation before and after training. RESULTS: the self-rating pressure in the two groups was lower than that before the training, and the pressure in the experimental group was lower than that in the control group (P < 0.05). After training, the positive emotion of the experimental group was higher than that of the control group, and the EG was lower than that of the CG (P < 0.05). After training, the score of attention bias of happy and neutral faces in the EG was higher than that of theCG, while the score of attention bias of sad and disgusted faces was lower than that of the CG (P < 0.05). After training, LF/HF and LFnorm in the EG were lower than those in the CG, and HFnorm was higher than those in the CG (P < 0.05). CONCLUSIONS: the training of visual search task can effectively improve the athletes' PA and AB of positive information, reduce the attention bias of negative information and psychological pressure, and relieve theSR.

Activation of NADPH/ROS pathway contributes to angiogenesis through JNK signaling in brain endothelial cells.

Recent evidences have shown that reactive oxygen species (ROS) are involved in regulating angiogenesis and preventing tissue injury. However, the precise molecular mechanisms behind ROS-induced angiogenesis are still unknown. The aim of the present study was to investigate the effects of ROS-induced angiogenesis in rat brain microvessel endothelial cells (rBMECs) and identify involving the signal pathways. For initial experiments, the rBMECs were incubated with different concentrations of hydrogen peroxide (H2O2). For the second experiments, the rBMECs were respectively treated with ROS scavenger dimethylthiourea (DMTU), NADPH oxidase (Nox) inhibitor apocynin, small interfering RNAs-mediated knock down Nox2 or Nox4, or pretreated with c-Jun N-terminal kinase (JNK) inhibitor SP600125. The cell proliferation, migration, tube formation, and the expressions of several important neuroangiogenic factors including vascular endothelial growth factor (VEGF), brain derived neurotrophic factor (BDNF), matrix metalloproteinase (MMP) -9 and phos-JNK were measured. Low level of H2O2 significantly promoted endothelial cell (EC) proliferation, migration and tube formation and upregulated levels of VEGF, BDNF, MMP-9 and phos-JNK. DMTU and apocynin significantly inhibited endothelial angiogenesis and downregulated these protein levels. As expected, knockdown of Nox2 or Nox4 expression blocked endothelial angiogenesis and downregulated the expressions of pro-neuroangiogenic factors. Furthermore, H2O2-induced endothelial angiogenesis and high expressions of pro-neuroangiogenic factors were decreased by SP600125. In conclusion, Nox-derived ROS were required for endothelial angiogenesis. Low level of ROS may activate JNK signaling pathway and upregulate pro-neuroangiogenic factors, ultimately mediating endothelial angiogenesis.

Prophylactic treatment of rapamycin ameliorates naturally developing and episode -induced heterotopic ossification in mice expressing human mutant ACVR1.

BACKGROUND: Fibrodysplasia ossificans progressiva (FOP) is a rare autosomal-dominant disease characterized by heterotopic ossification (HO) in soft tissues and caused by a mutation of the ACVR1A/ALK2 gene. Activin-A is a key molecule for initiating the process of HO via the activation of mTOR, while rapamycin, an mTOR inhibitor, effectively inhibits the Activin-A-induced HO. However, few reports have verified the effect of rapamycin on FOP in clinical perspectives. METHODS: We investigated the effect of rapamycin for different clinical situations by using mice conditionally expressing human mutant ACVR1A/ALK2 gene. We also compared the effect of rapamycin between early and episode-initiated treatments for each situation. RESULTS: Continuous, episode-independent administration of rapamycin reduced the incidence and severity of HO in the natural course of FOP mice. Pinch-injury induced HO not only at the injured sites, but also in the contralateral limbs and provoked a prolonged production of Activin-A in inflammatory cells. Although both early and injury-initiated treatment of rapamycin suppressed HO in the injured sites, the former was more effective at preventing HO in the contralateral limbs. Rapamycin was also effective at reducing the volume of recurrent HO after the surgical resection of injury-induced HO, for which the early treatment was more effective. CONCLUSION: Our study suggested that prophylactic treatment will be a choice of method for the clinical application of rapamycin for FOP.