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Background: Cervical spondylosis (CS) is a prevalent disorder that can have a major negative impact on quality of life. Traditional conservative treatment has limited efficacy, and electroacupuncture (EA) is a novel treatment option. We investigated the application and molecular mechanism of EA treatment in a rat model of cervical intervertebral disk degeneration (CIDD). Methods: The CIDD rat model was established, following which rats in the electroacupuncture (EA) group received EA. For overexpression of IL-22 or inhibition of JAK2-STAT3 signaling, the rats were injected intraperitoneally with recombinant IL-22 protein (p-IL-22) or the JAK2-STAT3 (Janus kinase 2—signal transducer and activator of transcription protein 3) inhibitor AG490 after model establishment. Rat nucleus pulposus (NP) cells were isolated and cultured. Cell counting kit-8 and flow cytometry were used to analyze the viability and apoptosis of the NP cells. Expression of IL-22, JAK2 and STAT3 was determined using RT-qPCR. Expression of IL-22/JAK2-STAT3 pathway and apoptosis related proteins was detected by Western blotting (WB). Results: EA protected the NP tissues of CIDD rats by regulating the IL-22/JAK2-STAT3 pathway. Overexpression of IL-22 significantly promoted the expression of tumor necrosis factor (TNF)-α, IL-6, IL-1β, matrix metalloproteinase (MMP)3 and MMP13 compared with the EA group. WB demonstrated that the expression of IL-22, p-JAK2, p-STAT3, caspase-3 and Bax in NP cells of the EA group was significantly reduced and Bcl-2 elevated compared with the model group. EA regulated cytokines and MMP through activation of IL-22/JAK2-STAT3 signaling in CIDD rat NP cells. Conclusion: We demonstrated that EA affected apoptosis by regulating the IL-22/JAK2-STAT3 pathway in NP cells and reducing inflammatory factors in the CIDD rat model. The results extend our knowledge of the mechanisms of action underlying the effects of EA as a potential treatment approach for CS in clinical practice. [ABSTRACT FROM AUTHOR]

The retrieval of soil moisture (SM) using the Global Navigation Satellite System-Reflectometry (GNSS-R) technique has become a prominent topic in recent years. Although prior research has reached a spatial resolution of up to 9 km through the Cyclone Global Navigation Satellite System (CYGNSS), it is insufficient to meet the requirements of higher spatial resolutions for hydrological or agricultural applications. In this paper, we present an SM downscaling method that fuses CYGNSS and SMAP SM. This method aims to construct a dataset of CYGNSS observables, auxiliary variables, and SMAP SM (36 km) products. It then establishes their nonlinear relationship at the same scale and finally builds a downscale retrieval model of SM using the eXtreme Gradient Boosting (XGBoost) algorithm. Focusing on the southern United States, the results indicate that the SM downscaling method exhibits robust performance during both the training and testing processes, enabling the generation of a CYGNSS SM product with a 1 day/3 km resolution. Compared to existing methods, the spatial resolution is increased threefold. Furthermore, in situ sites are utilized to validate the downscaled SM, and spatial correlation analysis is conducted using MODIS EVI and MODIS ET products. The CYGNSS SM obtained by the downscaling model exhibits favorable correlations. The high temporal and spatial resolution characteristics of GNSS-R are fully leveraged through the downscaled method proposed. Furthermore, this work provides a new perspective for enhancing the spatial resolution of SM retrieval using the GNSS-R technique. [ABSTRACT FROM AUTHOR]

Tensile experiments were conducted for Al-7.0Zn-2.5Mg-2.0Cu-0.1Zr-0.2Sc alloy in different aging states (18 h, 24 h, 36 h) with temperature environments including room temperature, −10 °C and −30 °C. Comparative studies were made on the evolution of the precipitate phase in alloys at three kinds of aging times and the evolution of tensile properties in alloys under different ambient temperatures. The findings showed that the precipitates in Al-7.0Zn-2.5Mg-2.0Cu-0.1Zr-0.2Sc alloy were mainly in the GP zone after the solution + aging treatment η' phase, the secondary Al3 (Sc, Zr) phase and the θ' (Al2Cu) phase. As the aging time was prolonged, the η' phase gradually grew and the PFZ gradually widened. At the three test temperatures, the tensile strength (TS) and yield strength (YS) of the alloys both showed a trend of first increasing before decreasing with the extension of aging time, while the elongation (A) and section shrinkage (Z) showed a decreasing trend. As the test temperature decreased, the TS and YS of the alloys increased and the A and Z of the alloys decreased. At room temperature, alloys showed a ductile fracture mode, which changed to mixed ductile and brittle fracture with decreasing test temperature. [ABSTRACT FROM AUTHOR]

To promote the functional applications of lotus root polysaccharides (LRPs), the effects of noncovalent polyphenol binding on their physicochemical properties, as well as antioxidant and immunomodulatory activities, were investigated. Ferulic acid (FA) and chlorogenic acid (CHA) were spontaneously bound to the LRP to prepare the complexes LRP-FA1, LRP-FA2, LRP-FA3, LRP-CHA1, LRP-CHA2 and LRP-CHA3, and their mass ratios of polyphenol to LRP were, respectively, 121.57, 61.18, 34.79, 2359.58, 1276.71 and 545.08 mg/g. Using the physical mixture of the LRP and polyphenols as a control, the noncovalent interaction between them in the complexes was confirmed by ultraviolet and Fourier-transform infrared spectroscopy. The interaction increased their average molecular weights by 1.11~2.27 times compared to the LRP. The polyphenols enhanced the antioxidant capacity and macrophage-stimulating activity of the LRP depending on their binding amount. Particularly, the DPPH radical scavenging activity and FRAP antioxidant ability were positively related to the FA binding amount but negatively related to the CHA binding amount. The NO production of the macrophages stimulated by the LRP was inhibited by the co-incubation with free polyphenols; however, the inhibition was eliminated by the noncovalent binding. The complexes could stimulate the NO production and tumor necrosis factor-α secretion more effectively than the LRP. The noncovalent binding of polyphenols may be an innovative strategy for the structural and functional modification of natural polysaccharides. [ABSTRACT FROM AUTHOR]

Tumor local chemotherapy employing injectable hydrogel reservoirs is a promising platform to achieve precise drug administration. However, balanced injectability, pH-responsiveness and long-term hydrolysis resistance of self-healing hydrogels remain appealing challenges. Herein, a modular preassembly strategy combining host-guest interactions with dynamic acylhydrazone bonds, was exploited to fabricate injectable cellulose-based hydrogels (CAAs) dressed with self-healing properties, pH-responsiveness and hydrolytic degradation resistance. Attributed to the host-guest interaction between β-cyclodextrin (CD) and 1-adamantane (AD), the hydrogels exhibited injectability, self-healing properties (healing efficiency of 97.5%) and rapid recovery (< 10 min) without external stimuli in physiological environment. Moreover, the hydrogels equipped with dynamic acylhydrazone linkages underwent slow hydrolytic degradation (> 30 days) and pH-responsive behavior, endowing the hydrogels with precise spatiotemporal drug release administration. The in vivo application of CAA as a carrier was studied using doxorubicin (DOX) model drug, and the results shows that using CAA as DOX carrier not only greatly enhances the anti-tumor efficacy of DOX, but also reduced the side effects of DOX. With the preassemble approach combining host-guest interactions with dynamic acylhydrazone bonds, this work demonstrated a multi-functional self-healing hydrogel as drug carrier developed by using natural polysaccharides, which offers a new avenue for the high-value utilization of biomass. The strategy demonstrated in the present work may also supply a pathway for the preparation and regulation of hydrogels as intelligent biomedicine materials. [Display omitted] [ABSTRACT FROM AUTHOR]

To meet the urgent requirement in complex wound treatment, the injectable self‐healing biocompatible hydrogel with tunable mechanical properties, adhesion, on‐demanding removability, antibacterial properties, and hemostasis is designed. For the first time, hydrogels are fabricated through dynamic enamine bonds among dodecane grafted quaternized chitosan (DQCS) and ketone group functionalized polyvinyl alcohol (PVA‐Ket) to achieve efficient wound closure. Owing to the dynamic enamine bond, the hydrogel exhibits self‐healing, injectability and suitable mechanical properties. It can be easily injected into wound, adhere tightly, and bear deformation damage. Dodecyl groups and quaternary amine groups endow the biocompatible hydrogels outstanding antibacterial feature, hemostatic performance, and tissue adhesiveness (40.05 ± 3.21 kPa), which greatly facilitate the wound healing process. Owing to interaction between the amino acid and PVA‐Ket, the hydrogel exhibits painless on‐demand dissolution behavior, causing uninjurious separation from wound sites. Furthermore, in vivo study demonstrates that the hydrogel promotes wound healing by upregulating growth factors, alleviating the inflammation and promoting angiogenesis, collagen deposition, and the growth of granulation tissue, leading to a better curative effect than the commercial gauze and Atrauman. Ag in infected and uninfected wounds. Thus, the multifunctional dynamic enamine‐based hydrogel with on‐demand removability has great potential in clinical applications. [ABSTRACT FROM AUTHOR]

Objective: To investigate the potential therapeutic effect in a rheumatoid arthritis model of stable human CD8+ regulatory T cells (hCD8+Tregs) induced by TGF-β1 and rapamycin (RAPA) in vitro.Methods: Human CD8+T cells were isolated from human peripheral blood mononuclear cells and induced/expanded with TGF-β1 and RAPA along with anti-CD3/28 beads and IL-2 in vitro and harvested as hCD8+Tregs. The phenotypes, suppressive characteristics, and stability of the hCD8+Tregs in an inflammatory microenvironment were examined in vitro. Human CD8+Tregs were transfused into an acollagen-induced arthritis (CIA) mouse model, and their therapeutic effects and related mechanisms were investigated.Results: Human CD8+Tregs induced by TGF-β1/RAPA showed high expression of Foxp3 and CD103, exhibited vigorous suppression ability, and were stable in inflammatory microenvironments. In CIA mice, the clinical scores, levels of anti-collagen IgG antibody, and cartilage destruction were significantly reduced after adoptive transfusion with hCD8+Tregs. Moreover, hCD8+Treg treatment significantly reduced the number of Th17 cells, increased the number of CD4+IFN-γ+T cells, and produced self CD4+Foxp3+Tregs in vivo. In an in vitro cell coculture assay, hCD8+Tregs significantly inhibited mouse CD4+ effector T cell proliferation, induced mouse CD4+Foxp3+Treg and CD4+IFN-γ+Th1 cell production, reduced Th17 cell development, and downregulated CD80/86 expression on mature DCs (mDCs).Conclusion: TGF-β1/RAPA can induce hCD8+Tregs with stable suppressive characteristics, which could significantly alleviate the severity of CIA based on their stable suppressive ability in an inflammatory microenvironment and further influence the function of other downstream cell subtypes. Human CD8+Tregs might be a therapeutic strategy for rheumatoid arthritis. [ABSTRACT FROM AUTHOR]

Abstract This study was conducted to evaluate whether baicalin inhibits red blood cell (RBC) immunization and elucidate the underlying mechanism. We used human RBCs with adjuvant lipopolysaccharide (LPS) and transfused mice to induce antibodies as an experimental system for studying the effect of baicalin on RBC immunization. Mice were divided into a human RBC transfused positive control group administered with human RBC and LPS intravenously once or weekly for 4 weeks, control group administered dexamethasone (DEX) intraperitoneally daily for 4 weeks, and treatment group administered baicalin intraperitoneally daily for 4 weeks. Assessment of human RBC immunization was performed by measuring serum immunoglobulin G (IgG) and immunoglobulin M (IgM) against human RBC weekly. Lymphocyte changes in spleen were monitored by flow cytometry. We found that baicalin treatment significantly decreased serum IgG but not IgM production in a time and does dependent manner, with a concomitant reduction in Th17 cells and increase in CD4 regulatory T cells in the spleen. The percentage of CD4-positive cells in the spleen was not decreased in the baicalin-treated group but was decreased in the dexamethasone-treated group. In conclusion, baicalin inhibited RBC immunization, particularly IgG production by regulating the Treg/Th17 axis without damaging spleen function. Highlights • LPS induced robust antibody production in mouse model of blood transfusion. • Baicalin inhibited Th17 development and increase Treg proportion. • Baicalin inhibited IgG production in mouse model of blood transfusion. [ABSTRACT FROM AUTHOR]

Two novel poly(pyridinylene vinylene) (PPV)-type conjugated polyelectrolytes 2,6-PPYPV-(2+) and 3,5-PPYPV-(2+) were synthesized via Heck coupling reaction and characterized by 1H nuclear magnetic resonance (NMR), ultraviolet-visible (UV-Vis) and photoluminescence (PL) spectroscopy. The two polymers consisting of meta-position substituted pyridinylenes as the metal recognition unit and a water-soluble divinyl-benzene derivative in the backbones. 2,6-PPYPV-(2+) and 3,5-PPYPV-(2+) both exhibit strongest fluorescence in methanol and weakest fluorescence in water among common polar solvents. In respect of ion detection, 3,5-PPYPV-(2+) has an excellent identifiability for Pd2+ in methanol with the K_SV value of 1.1×105m−1 while 2,6-PPYPV-(2+) has a good selectivity for Cu2+ and Hg2+ in aqueous solution. And all the Stern-Volmer plots of 2,6-PPYPV-(2+) and 3,5-PPYPV-(2+) in fluorescence quenching for metal ions have favorable tendencies. All the results suggest that 2,6-PPYPV-(2+) and 3,5-PPYPV-(2+) are promising materials in the applications of high performance chemosensors for some specific metal ions. [ABSTRACT FROM AUTHOR]

Objective: Tolerogenic dendritic cells (tDCs) can expand TGF-β-induced regulatory T cells (iTregs); however, the therapeutic utility of these expanded iTregs in autoimmune diseases remains unknown. We sought to determine the properties of iTregs expanded by mature tolerogenic dendritic cells (iTregmtDC) in vitro and explore their potential to ameliorate collagen-induced arthritis (CIA) in a mouse model.Methods: After induction by TGF-β and expansion by mature tDCs (mtDCs), the phenotype and proliferation of iTregmtDC were assessed by flow cytometry. The ability of iTregs and iTregmtDC to inhibit CD4+ T cell proliferation and suppress Th17 cell differentiation was compared. Following adoptive transfer of iTregs and iTregmtDC to mice with CIA, the clinical and histopathologic scores, serum levels of IFN-γ, TNF-α, IL-17, IL-6, IL-10, TGF-β and anti-CII antibodies, and the distribution of the CD4+ Th subset were assessed.Results: Compared with iTregs, iTregmtDC expressed higher levels of Foxp3 and suppressed CD4+ T cell proliferation and Th17 cell differentiation to a greater extent. In vivo, iTregmtDC reduced the severity and progression of CIA more significantly than iTregs, which was associated with a modulated inflammatory cytokine profile, reduced anti-CII IgG levels, and polarized Treg/Th17 balance.Conclusion: This study highlights the potential therapeutic utility of iTregmtDC in autoimmune arthritis and should facilitate the future design of iTreg immunotherapeutic strategies. [ABSTRACT FROM AUTHOR]

ABSTRACT Two novel ID-based water-soluble conjugated polymers (+)-PIDPV and (−)-PIDPV were synthesized by Heck coupling reaction. These two polyelectrolytes are both consisted of isoindigo units and phenylenevinylene units. In the UV-vis absorption spectra, both (+)-PIDPV and (−)-PIDPV exhibit broad absorption bands that almost cover the whole visible region. Photophysical investigations reveal that the fluorescence of water-soluble PPV can be efficiently quenched by oppositely charged PIDPV at a very low concentration. Cationic PPV shows an efficient quenching effect with ΚSV = 1.01 × 106 M−1 in the presence of (−)-PIDPV while the anionic PPV gives a lager quenching constant with ΚSV = 1.71 × 106 M−1 in the presence of (+)-PIDPV. Furthermore, the blend films of water-soluble PPVs and oppositely charged PIDPV also exhibit excellent quenching effect. These properties suggest that (+)-PIDPV and (−)-PIDPV are promising materials in the application of ionic photoactive layer in the organic solar cells. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2015, 53, 2223-2237 [ABSTRACT FROM AUTHOR]

An ideal wound dressing should have excellent antimicrobial properties and provide a suitable microenvironment for regenerating damaged skin tissue. In this study, we utilized sericin to biosynthesize silver nanoparticles in situ and introduced curcumin to obtain Sericin-AgNPs/Curcumin (Se-Ag/Cur) antimicrobial agent. The hybrid antimicrobial agent was then encapsulated in a physically double cross-linking 3D structure network (Sodium alginate-Chitosan, SC) to obtain the SC/Se-Ag/Cur composite sponge. The 3D structural networks were constructed through electrostatic interactions between sodium alginate and chitosan and ionic interactions between sodium alginate and calcium ions. The prepared composite sponges have excellent hygroscopicity (contact angle 51.3° ± 5.6°), moisture retention ability, porosity (67.32 % ± 3.37 %), and mechanical properties (>0.7 MPa) and exhibit good antibacterial ability against Pseudomonas aeruginosa (P. aeruginosa) and Staphylococcus aureus (S. aureus). In addition, in vivo experiments have shown that the composite sponge promotes epithelial regeneration and collagen deposition in wounds infected with S. aureus or P. aeruginosa. Tissue immunofluorescence staining analysis confirmed that the SC/Se-Ag/Cur complex sponge stimulated upregulated expression of CD31 to promote angiogenesis while downregulating TNF-α expression to reduce inflammation. These advantages make it an ideal candidate for infectious wound repair materials, providing an effective repair strategy for clinical skin trauma infections. [ABSTRACT FROM AUTHOR]