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1.
Front Genet ; 15: 1429844, 2024.
Article in English | MEDLINE | ID: mdl-39015772

ABSTRACT

Mesenchymal stem cells (MSCs) have promising potential for bone tissue engineering in bone healing and regeneration. They are regarded as such due to their capacity for self-renewal, multiple differentiation, and their ability to modulate the immune response. However, changes in the molecular pathways and transcription factors of MSCs in osteogenesis can lead to bone defects and metabolic bone diseases. DNA methylation is an epigenetic process that plays an important role in the osteogenic differentiation of MSCs by regulating gene expression. An increasing number of studies have demonstrated the significance of DNA methyltransferases (DNMTs), Ten-eleven translocation family proteins (TETs), and MSCs signaling pathways about osteogenic differentiation in MSCs. This review focuses on the progress of research in these areas.

2.
Comput Struct Biotechnol J ; 23: 2251-2266, 2024 Dec.
Article in English | MEDLINE | ID: mdl-38827236

ABSTRACT

Background: Acting as mediators in cell-matrix and cell-cell communication, matricellular proteins play a crucial role in cancer progression. Thrombospondins (TSPs), a type of matricellular glycoproteins, are key regulators in cancer biology with multifaceted roles. Although TSPs have been implicated in anti-tumor immunity and epithelial-mesenchymal transition (EMT) in several malignancies, their specific roles to colon cancer remain elusive. Addressing this knowledge gap is essential, as understanding the function of TSPs in colon cancer could identify new therapeutic targets and prognostic markers. Methods: Analyzing 1981 samples from 10 high-throughput datasets, including six bulk RNA-seq, three scRNA-seq, and one spatial transcriptome dataset, our study investigated the prognostic relevance, risk stratification value, immune heterogeneity, and cellular origin of TSPs, as well as their influence on cancer-associated fibroblasts (CAFs). Utilizing survival analysis, unsupervised clustering, and functional enrichment, along with multiple correlation analyses of the tumor-microenvironment (TME) via Gene Set Variation Analysis (GSVA), spatial localization, Monocle2, and CellPhoneDB, we provided insights into the clinical and cellular implications of TSPs. Results: First, we observed significant upregulation of THBS2 and COMP in colon cancer, both of which displayed significant prognostic value. Additionally, we detected a significant positive correlation between TSPs and immune cells, as well as marker genes of EMT. Second, based on TSPs expression, patients were divided into two clusters with distinct prognoses: the high TSPs expression group (TSPs-H) was characterized by pronounced immune and stromal cell infiltration, and notably elevated T-cell exhaustion scores. Subsequently, we found that THBS2 and COMP may be associated with the differentiation of CAFs into pan-iCAFs and pan-dCAFs, which are known for their heightened matrix remodeling activities. Moreover, THBS2 enhanced CAFs communication with vascular endothelial cells and monocyte-macrophages. CAFs expressing THBS2 (THBS2+ CAFs) demonstrated higher scores across multiple signaling pathways, including angiogenic, EMT, Hedgehog, Notch, Wnt, and TGF-ß, when compared to THBS2- CAFs. These observations suggest that THBS2 may be associated with stronger pro-carcinogenic activity in CAFs. Conclusions: This study revealed the crucial role of TSPs and the significant correlation between THBS2 and CAFs interactions in colon cancer progression, providing valuable insights for targeting TSPs to mitigate cancer progression.

3.
Ecotoxicol Environ Saf ; 277: 116326, 2024 Jun 01.
Article in English | MEDLINE | ID: mdl-38640800

ABSTRACT

The available information regarding the impact of antimony (Sb), a novel environmental pollutant, on the intestinal microbiota and host health is limited. In this study, we conducted physiological characterizations to investigate the response of adult zebrafish to different environmental concentrations (0, 30, 300, and 3000 µg/L) of Sb over a period of 14 days. Biochemical and pathological changes demonstrated that Sb effectively compromised the integrity of the intestinal physical barrier and induced inflammatory responses as well as oxidative stress. Analysis of both intestinal microbial community and metabolome revealed that exposure to 0 and 30 µg/L of Sb resulted in similar microbiota structures; however, exposure to 300 µg/L altered microbial communities' composition (e.g., a decline in genus Cetobacterium and an increase in Vibrio). Furthermore, exposure to 300 µg/L significantly decreased levels of bile acids and glycerophospholipids while triggering intestinal inflammation but activating self-protective mechanisms such as antibiotic presence. Notably, even exposure to 30 µg/L of Sb can trigger dysbiosis of intestinal microbiota and metabolites, potentially impacting fish health through the "microbiota-intestine-brain axis" and contributing to disease initiation. This study provides valuable insights into toxicity-related information concerning environmental impacts of Sb on aquatic organisms with significant implications for developing management strategies.


Subject(s)
Antimony , Gastrointestinal Microbiome , Water Pollutants, Chemical , Zebrafish , Animals , Gastrointestinal Microbiome/drug effects , Water Pollutants, Chemical/toxicity , Antimony/toxicity , Oxidative Stress/drug effects , Metabolome/drug effects , Metabolomics
4.
iScience ; 27(2): 109008, 2024 Feb 16.
Article in English | MEDLINE | ID: mdl-38352228

ABSTRACT

Disruption of circadian rhythms during fetal development may predispose mice to developing heart disease later in life. Here, we report that male, but not female, mice that had experienced chronic circadian disturbance (CCD) in utero were more susceptible to pathological cardiac remodeling compared with mice that had developed under normal intrauterine conditions. CCD-treated males showed ventricular chamber dilatation, enhanced myocardial fibrosis, decreased contractility, higher rates of induced tachyarrhythmia, and elevated expression of biomarkers for heart failure and myocardial remodeling. In utero CCD exposure also triggered sex-dependent changes in cardiac gene expression, including upregulation of the secretoglobin gene, Scgb1a1, in males. Importantly, cardiac overexpression of Scgb1a1 was sufficient to induce myocardial hypertrophy in otherwise naive male mice. Our findings reveal that in utero CCD exposure predisposes male mice to pathological remodeling of the heart later in life, likely as a consequence of SCGB1A1 upregulation.

5.
Small ; 20(8): e2307354, 2024 Feb.
Article in English | MEDLINE | ID: mdl-37821406

ABSTRACT

Aqueous all-iron redox flow batteries (RFBs) are promising competitors for next-generation grid-scale energy storage applications. However, the high-performance operation of all-iron RFBs in a wider temperature range is greatly hindered by inferior iron plating/stripping reaction and low solid-liquid transition temperature at Fe anode. Herein, a universal electrolyte additive design strategy for all-iron RFBs is reported, which realizes a highly reversible and dendrite-free Fe anode at low temperatures. Quantum chemistry calculations first screen several organic molecules with oxygen-containing functional groups and identify N,N-Dimethylacetmide (DMAc) as a potential candidate with low cost, high solubility, and strong interactions with Fe2+ and H2 O. Combined experimental characterizations and theoretical calculations subsequently demonstrate that adding DMAc into the FeCl2 solution effectively reshapes the primary solvation shell of Fe2+ via the Fe2+ -O (DMAc) bond and breaks hydrogen-bonding network of water through intensified H-bond interaction between DMAc and H2 O, thereby affording the Fe anode with enhanced Fe/Fe2+ reversibility and lower freezing point. Consequently, the assembled all-iron RFB achieves an excellent combination of high power density (25 mW cm-2 ), long charge-discharge cycling stability (95.59% capacity retention in 103 h), and preeminent battery efficiency at -20 °C (95% coulombic efficiency), which promise a future for wider temperature range operation of all-iron RFBs.

6.
J Sci Food Agric ; 104(3): 1599-1608, 2024 Feb.
Article in English | MEDLINE | ID: mdl-37847530

ABSTRACT

BACKGROUND: Recently, germinated brown rice (GBR) has gained substantial attention as a functional food because of its nutritional attributes. Notably, pulsed light technology (PLT) has emerged as a promising tool for enhancing rice germination and, consequently, has improved the nutritional and functional qualities of GBR-derived products. However, further research is required to comprehensively understand the impact of PLT on GBR physicochemical properties. The present study aimed to investigate the stimulating effects of PLT on starch hydrolysis, starch structure and functional properties of GBR. RESULTS: The PLT substantially boosted α-amylase activity during brown rice germination, leading to a 10.9% reduction in total starch content and a 17.3% increase in reducing sugar content, accompanied by elevated free water levels. Structural analysis indicated no changes in starch crystalline types, whereas gelatinization temperature slightly increased. Pasting properties exhibited a significant drop in peak viscosity. Scanning electron microscopy showed surface erosion of starch granules with microstructural changes. Furthermore, correlation analysis established positive links between α-amylase activity, reducing sugar accumulation, starch structure and functional properties in GBR. CONCLUSION: The present study demonstrates that PLT enhanced the physicochemical properties of GBR starch, significantly improving the stability of GBR products, thereby contributing to expanded applicability of rice starch in the food industry. © 2023 Society of Chemical Industry.


Subject(s)
Oryza , Starch , Starch/chemistry , Hydrolysis , Oryza/chemistry , alpha-Amylases , Sugars
7.
iScience ; 26(9): 107609, 2023 Sep 15.
Article in English | MEDLINE | ID: mdl-37664593

ABSTRACT

Tubulointerstitial abnormalities contribute to the progression of diabetic kidney disease (DKD). However, the underlying mechanism of the pathobiology of tubulointerstitial disease is largely unknown. Here, we showed that MYCT1 expression was downregulated in in vitro and in vivo DKD models. Adeno-associated virus (AAV)-Myct1 significantly attenuated renal dysfunction and tubulointerstitial fibrosis in diabetic db/db mice and downregulated Sp1 transcription and TGF-ß1/SMAD3 pathway activation. In human proximal tubular epithelial cells, high glucose-induced high expression of SP1 and TGF-ß1/SMAD3 pathway activation as well as overaccumulation of extracellular matrix (ECM) were abrogated by MYCT1 overexpression. Mechanistically, the binding of VDR to the MYCT1 promoter was predicted and confirmed using dual-luciferase reporter and ChIP analysis. VDR transcriptionally upregulates MYCT1. Our data reveal MYCT1 as a new and potential therapeutic target in treating DKD.

8.
Opt Lett ; 48(7): 1866-1869, 2023 Apr 01.
Article in English | MEDLINE | ID: mdl-37221786

ABSTRACT

In this Letter, a simple optical vortex convolution generator is proposed where a microlens array (MLA) is utilized as an optical convolution device, and a focusing lens (FL) is employed to obtain the far field, which can convert a single optical vortex into a vortex array. Further, the optical field distribution on the focal plane of the FL is theoretically analyzed and experimentally verified using three MLAs of different sizes. Moreover, in the experiments, behind the FL, the self-imaging Talbot effect of the vortex array is also observed. Meanwhile, the generation of the high-order vortex array is also investigated. This method, with a simple structure and high optical power efficiency, can generate high spatial frequency vortex arrays using devices with low spatial frequency and has excellent application prospects in the field of optical tweezers, optical communication, optical processing, etc.

9.
Opt Express ; 31(9): 13665-13671, 2023 Apr 24.
Article in English | MEDLINE | ID: mdl-37157249

ABSTRACT

We propose an adaptive optics (AO) pre-compensation scheme to improve the transmission quality of orbital angular momentum (OAM) beams in atmospheric turbulence. The distortion wavefront caused by atmospheric turbulence is obtained with the Gaussian beacon from the receiver. The AO system imposes the conjugate distortion wavefront onto the outgoing OAM beams at the transmitter, tto achieve the pre-compensation. Using the scheme, we conducted transmission experiments with different OAM beams in the simulated atmospheric turbulence. The experimental results indicated that the AO pre-compensation scheme can improve the transmission quality of the OAM beams in the atmospheric turbulence in real-time. It is found that the turbulence-induced crosstalk effects on neighboring modes are reduced by an average of 6 dB, and the system power penalty is improved by an average of 12.6 dB after pre-compensation.

10.
Front Immunol ; 14: 1041149, 2023.
Article in English | MEDLINE | ID: mdl-37006293

ABSTRACT

Rotavirus (RV) causes 200,000 deaths per year and imposes a serious burden to public health and livestock farming worldwide. Currently, rehydration (oral and intravenous) remains the main strategy for the treatment of rotavirus gastroenteritis (RVGE), and no specific drugs are available. This review discusses the viral replication cycle in detail and outlines possible therapeutic approaches including immunotherapy, probiotic-assisted therapy, anti-enteric secretory drugs, Chinese medicine, and natural compounds. We present the latest advances in the field of rotavirus antivirals and highlights the potential use of Chinese medicine and natural compounds as therapeutic agents. This review provides an important reference for rotavirus prevention and treatment.


Subject(s)
Gastroenteritis , Rotavirus Infections , Rotavirus , Humans , Rotavirus Infections/drug therapy , Rotavirus Infections/prevention & control , Gastroenteritis/drug therapy , Gastroenteritis/prevention & control , Antiviral Agents/therapeutic use , Hospitalization
11.
ACS Appl Mater Interfaces ; 14(47): 53370-53379, 2022 Nov 30.
Article in English | MEDLINE | ID: mdl-36379045

ABSTRACT

Active anticorrosive organic coatings adopting microcapsules (MCs) have lately attracted extensive attention as they were proven to be effective to minimize metal corrosions and offer a long-lasting protection performance. Herein, a novel environmental-friendly active corrosion protection system was designed for aluminum alloy 2024 (AA2024) based on water-based polyurethane coatings with the addition of water and alkaline pH-responsive smart MCs, which is fabricated by utilizing 2-mercaptobenzothiazole (2-MBT) as an inhibitor, halloysite clay nanotubes (HNTs) as an inhibitor carrier, and the natural polyelectrolytes ε-poly-l-lysine (ε-PLL) and sodium alginate (SA) as layer-by-layer (LBL) encapsulation polyelectrolytes. Salt spray tests and electrochemical measurements prove that the scratched coatings with embedded MCs possess an excellent self-healing performance by forming an adsorption layer of released 2-MBT on the AA2024 surface, thereby providing over 90% inhibition efficiency within 6 days' immersion. The UV-vis spectrophotometer results further showed that the release of 2-MBT is a three-stage long-term process sensitive to water and alkaline pH value, while the outward release rate is both regulated by the solubility of 2-MBT and the SA layer. The fabricated MCs not only offer a great promise to provide an excellent self-healing performance but also shed light on the future design of advanced MCs on demand based on the LBL technique.

12.
Opt Express ; 30(17): 30623-30629, 2022 Aug 15.
Article in English | MEDLINE | ID: mdl-36242162

ABSTRACT

The vortex beams carried Orbital Angular Momentum (OAM) have recently generated considerable interest due to their potential used in communication systems to increase transmission capacity and spectral efficiency. In this paper, the distorted wavefront detection based on Shack-Hartmann wavefront sensor (HWS) for the vortex beams is investigated. The detection slope of the helical phase sub-spot pattern is used as the calibrated slope zero point, and then the distortion phase of the vortex beam is detected by the HWS. Simulation and experimental results demonstrate that this method can detect the distortion phase of vortex beam with high precision and high frame rate, which is expected to accelerate the application of optical communication systems with vortex beams.

13.
Small ; 18(49): e2204356, 2022 12.
Article in English | MEDLINE | ID: mdl-36310140

ABSTRACT

Developing low-cost all-iron hybrid redox flow batteries (RFBs) presents a practical alternative to the high-cost all-vanadium RFBs and is deemed vital for grid-scale energy storage applications. However, the intrinsically poor Fe anode reversibility associated with the deposition and dissolution of metallic iron greatly limits the cycling performance and long-term stability of all-iron hybrid RFBs. Herein, a highly reversible and dendrite-free Fe anode is reported for all-iron RFBs through regulation of polar solvent dimethyl sulfoxide (DMSO) on FeCl2 anolyte, which simultaneously reshapes Fe2+ solvation structure and induces controllable oriented Fe deposition. Combining both experimental and theoretical analyses, the polar DMSO additives prove effective in replacing H2 O molecule from the primary solvation shell of Fe2+ cation via the Fe2+ -O (DMSO) bond and meanwhile induces a fine-grained Fe nucleation on the preferred Fe (110) plane, which are responsible for the minimized hydrogen evolution and dendrite-free Fe deposition that significantly enhance Fe anode reversibility. The all-iron RFB based on the proposed FeCl2 -DMSO anolyte demonstrates an excellent combination of peak power density of 134 mW cm-2 , high energy efficiency of 75% at 30 mA cm-2 , and high capacity retention of 98.6% over 200 cycles, which presents the best performance of all-iron RFBs among previously reported research.


Subject(s)
Electric Power Supplies , Iron , Electrodes , Dimethyl Sulfoxide , Hydrogen
14.
Opt Express ; 30(16): 28892-28904, 2022 Aug 01.
Article in English | MEDLINE | ID: mdl-36299076

ABSTRACT

In this paper, the amplitude properties of the Laguerre-Gaussian (LG) vortex beams are analyzed theoretically and demonstrated experimentally. Firstly, the ring width of the LG vortex beam is almost a constant, which can be considered to be independent of the topological charge (l) and only determined by the waist radius ω(z), and its general expression is derived via investigating Lambert W function. On this basis, concise expressions for inner and outer ring radii, ratio of inner and outer ring radius, ring area and beam divergence are also given out. Moreover, modification functions are added to obtain more accurate expressions. In the experiment, a spatial light modulator is employed to generate the LG vortex beams with l = 1∼20 at ω0 = 0.3mm and ω0=0.4mm, and the LG vortex beams with l=10 at different propagation distances. The experimental results are in good agreement with the theoretical values. This work may help researchers to better understand the LG vortex beam and provide a useful guideline for its further applications.

15.
Huan Jing Ke Xue ; 43(7): 3884-3894, 2022 Jul 08.
Article in Chinese | MEDLINE | ID: mdl-35791571

ABSTRACT

A long-term fertilization experiment with a system of rice-wheat rotation was conducted in Chengdu Plain. Three fertilization treatments including conventional fertilization (T1), pig manure substituting for 50% nitrogen fertilizer (T2), and T2 plus straw (T3) were set up to study the characteristics of microbial carbon source utilization of soil and dissolved organic matter (DOM). The results showed that T3 improved the soil microbial carbon source metabolism in comparison with those of the T1 and T2 treatments; the average color change rate (AWCD) increased by 16% and 48%, respectively. Meanwhile, T3 improved the soil DOM microbial carbon source metabolism, and the AWCD value was 0.43. The highest Shannon, Simpson, and McIntosh indexes of soil and DOM were all found in the T3 treatment, and the Shannon, Simpson, and McIntosh indexes of DOM were 2.73, 0.91, and 3.75, respectively. The results of principal component analysis and enrichment analysis showed that the main carbon sources used by microorganisms of soil and DOM were different under different fertilization treatments. For DOM, the main carbon source used by microorganisms in the T1 and T2 treatments was sugar, whereas T3 increased the utilization of amino acids, carboxylic acids, polymers, and amines. The changes in soil pH and texture were the main factors that caused the difference in soil DOM microbial carbon source metabolism. In conclusion, the application of organic fertilizer (pig manure plus straw) significantly increased the microbial community diversity and carbon source metabolic capacity of soil and DOM and promoted the diversification of microbial carbon source preference.


Subject(s)
Carbon , Soil , Animals , Carbon/chemistry , Dissolved Organic Matter , Fertilizers , Manure , Soil/chemistry , Soil Microbiology , Swine
16.
Front Med (Lausanne) ; 9: 860798, 2022.
Article in English | MEDLINE | ID: mdl-35433730

ABSTRACT

Objectives: The purpose of this study was to investigate the baseline independent risk factors for predicting 6-month mortality of patients with anti-melanoma differentiation-associated gene 5 (anti-MDA5)-positive dermatomyositis (DM) and develop a matrix prediction model formed by these risk factors. Methods: The hospitalized patients with DM who completed at least 6-month follow-up were recruited as a derivation cohort. The primary exposure was defined as positive anti-MDA5 at the baseline. The primary outcome was all-cause 6-month mortality after enrollment. A matrix prediction model was developed in the derivation cohort, and another published cohort was used for external validation. Results: In derivation cohort, 82 patients with DM were enrolled (mean age of onset 50 ± 11 years and 63% women), with 40 (49%) showing positive anti-MDA5. Gottron sign/papules (OR: 5.135, 95%CI: 1.489-17.708), arthritis (OR: 5.184, 95%CI: 1.455-18.467), interstitial lung disease (OR: 7.034, 95%CI: 1.157-42.785), and higher level of C4 (OR: 1.010, 95%CI: 1.002-1.017) were the independent associators with positive anti-MDA5 in patients with DM. Patients with anti-MDA5-positive DM had significant higher 6-month all-cause mortality than those with anti-MDA5-negative (30 vs. 0%). Among the patients with anti-MDA5-positive DM, compared to the survivors, non-survivors had significantly advanced age of onset (59 ± 6 years vs. 46 ± 9 years), higher rates of fever (75 vs. 18%), positive carcinoma embryonic antigen (CEA, 75 vs. 14%), higher level of ferritin (median 2,858 ug/L vs. 619 ug/L, all p < 0.05). A stepwise multivariate Cox regression showed that ferritin ≥1,250 µg/L (HR: 10.4, 95%CI: 1.8-59.9), fever (HR: 11.2, 95%CI: 2.5-49.9), and positive CEA (HR: 5.2, 95%CI: 1.0-25.7) were the independent risk factors of 6-month mortality. A matrix prediction model was built to stratify patients with anti-MDA5-positive DM into different subgroups with various probabilities of 6-month mortality risk. In an external validation cohort, the observed 6-month all-cause mortality was 78% in high-risk group, 43% in moderate-risk group, and 25% in low-risk group, which shows good accuracy of the model. Conclusion: Baseline characteristics such as fever, ferritin ≥1,250 µg/L, and positive CEA are the independent risk factors for 6-month all-cause mortality in patients with anti-MDA5-positive DM. A novel matrix prediction model composed of these three clinical indicators is first proposed to provide a chance for the exploration of individual treatment strategies in anti-MDA5-positive DM subgroups with various probabilities of mortality risk.

17.
Opt Express ; 30(3): 3793-3803, 2022 Jan 31.
Article in English | MEDLINE | ID: mdl-35209631

ABSTRACT

In this paper, a novel phase modulation technique based on a corner-cube reflector (CCR) array is proposed and demonstrated experimentally. The piezoceramics are linked behind each CCR. When the beams irradiate on the CCR array, the phase modulation can be realized by applying a voltage to piezoceramics to control the spatial location of each CCR. The piston phase errors of the device itself are compensated by employing the stochastic parallel gradient descent (SPGD) algorithm. Then, the piezoceramics are loaded with preset voltages to obtain the expected phase, and the anticipative optical field is generated. In the experiment, the piston phase errors of the 7-way and 19-way CCR array are corrected well. In order to further verify the phase control capability of the device, a vortex beam carrying orbital angular momentum (OAM) of 1 is generated by utilizing the 6-way CCR array. The experimental results confirm the feasibility of the concept.

18.
Chem Biol Drug Des ; 98(5): 828-834, 2021 11.
Article in English | MEDLINE | ID: mdl-34411427

ABSTRACT

Purple sweet potato polysaccharide was extracted via hot water, and it was chemically modified by phosphorus oxychloride-pyridine to obtain phosphorylated polysaccharide from purple sweet potato (P-PPSP) with certain degrees of substitution. Furthermore, the structure and antioxidant activity in vitro of PPSP and phosphorylated derivative were compared. The result indicated that the phosphorylation modification product of polysaccharide from purple sweet potato could improve the scavenging effect on hydroxyl radical and superoxide anion of PPSP, significantly. It also could improve the anti-lipid peroxidation ability while fail to improve the reducing ability of PPSP.


Subject(s)
Antioxidants/chemistry , Ipomoea batatas/chemistry , Plant Extracts/chemistry , Polysaccharides/chemistry , Antioxidants/pharmacology , Free Radical Scavengers/chemistry , Humans , Lipid Peroxidation , Oxidation-Reduction , Phosphorylation , Plant Extracts/pharmacology , Polysaccharides/pharmacology , Superoxides/chemistry
19.
Biomater Sci ; 9(11): 4169-4177, 2021 Jun 04.
Article in English | MEDLINE | ID: mdl-33977985

ABSTRACT

Injectable hydrogels hold promise in biomedical applications due to their noninvasive administration procedure and capacity enabling the filling of irregularly shaped defects. Protein-based hydrogels provide features including good biocompatibility and inherent biofunction. However, challenges still remain to develop a protein-based injectable hydrogel in a convenient way due to the limited active groups in proteins. Keratins are a group of cysteine-rich structural proteins found abundantly in skin and skin appendages. In this work, we utilized keratin and the Au(iii) salt to develop an injectable hydrogel based on the dynamic exchange between disulfide bonds (S-S) and gold(i)-thiolates (Au-S). Such a hydrogel could be prepared at the physiological pH and applied as an injectable hydrogel for biomedical applications including hemostatic and wound dressing materials. Our findings demonstrated that this keratin injectable hydrogel showed a good hemostatic effect in both tail amputation and liver injury models. Moreover, it was proved efficient as a drug loading carrier, and the deferoxamine-loaded hydrogel showed a desirable wound healing effect in a full-thickness excision wound model.


Subject(s)
Hemostatics , Hydrogels , Bandages , Keratins , Wound Healing
20.
Materials (Basel) ; 14(6)2021 Mar 13.
Article in English | MEDLINE | ID: mdl-33805799

ABSTRACT

In order to meet the increasingly stringent requirements for heat resistance and barrier properties in the packaging and electronic device encapsulation field. A high-barrier polyimide (NAPPI) contains naphthalene ring and amide group was prepared by polymerization of a novel diamine (NAPDA) and pyromellitic dianhydride. The structure and properties of diamine monomers and polymers were characterized. Results show that the NAPPI exhibits superior barrier properties with extremely low water vapor and oxygen transmission rate values of 0.14 g·m-2·day-1 and 0.04 cm3·m-2·day-1, respectively. In addition, the NAPPI presents outstanding mechanical properties and thermal stability as well. This article attempts to explore the relationship between NAPPI structure and barrier properties by combining experiment and simulation. Studies on positron annihilation lifetime spectroscopy, Wide angle X-ray diffractograms and molecular dynamics simulations prove that the NAPPI has smaller interplanar spacing and higher chain regularity. In addition, the strong chain rigidity and interchain cohesion of NAPPI due to the presence of the rigid naphthalene ring and a large number of hydrogen bond interactions formed by amide groups result in compact chain packing and smaller free volume, which reduces the solubility and diffusibility of small molecules in the matrix. In general, the simulation results are consistent with the experimental results, which are important for understanding the barrier mechanism of NAPPI.

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