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1.
Sci Rep ; 13(1): 10328, 2023 Jun 26.
Article in English | MEDLINE | ID: mdl-37365272

ABSTRACT

Crystal chemical design principles were applied to synthesise novel U4+ dominant and titanium excess betafite phases Ca1.15(5)U0.56(4)Zr0.17(2)Ti2.19(2)O7 and Ca1.10(4)U0.68(4)Zr0.15(3)Ti2.12(2)O7, in high yield (85-95 wt%), and ceramic density reaching 99% of theoretical. Substitution of Ti on the A-site of the pyrochlore structure, in excess of full B-site occupancy, enabled the radius ratio (rA/rB = 1.69) to be tuned into the pyrochlore stability field, approximately 1.48 ≲ rA/rB ≲ 1.78, in contrast to the archetype composition CaUTi2O7 (rA/rB = 1.75). U L3-edge XANES and U 4f7/2 and U 4f5/2 XPS data evidenced U4+ as the dominant speciation, consistent with the determined chemical compositions. The new betafite phases, and further analysis reported herein, point to a wider family of actinide betafite pyrochlores that could be stabilised by application of the underlying crystal chemical principle applied here.

2.
Sci Rep ; 13(1): 9329, 2023 Jun 08.
Article in English | MEDLINE | ID: mdl-37291129

ABSTRACT

Indium (In) is a neutron absorbing additive that could feasibly be used to mitigate criticality in ceramic wasteforms containing Pu in the immobilised form, for which zirconolite (nominally CaZrTi2O7) is a candidate host phase. Herein, the solid solutions Ca1-xZr1-xIn2xTi2O7 (0.10 ≤ x ≤ 1.00; air synthesis) and Ca1-xUxZrTi2-2xIn2xO7 (x = 0.05, 0.10; air and argon synthesis) were investigated by conventional solid state sintering at a temperature of 1350 °C maintained for 20 h, with a view to characterise In3+ substitution behaviour in the zirconolite phase across the Ca2+, Zr4+ and Ti4+ sites. When targeting Ca1-xZr1-xIn2xTi2O7, single phase zirconolite-2M was formed at In concentrations of 0.10 ≤ x ≤ 0.20; beyond x ≥ 0.20, a number of secondary In-containing phases were stabilised. Zirconolite-2M remained a constituent of the phase assemblage up to a concentration of x = 0.80, albeit at relatively low concentration beyond x ≥ 0.40. It was not possible to synthesise the In2Ti2O7 end member compound using a solid state route. Analysis of the In K-edge XANES spectra in the single phase zirconolite-2M compounds confirmed that the In inventory was speciated as trivalent In3+, consistent with targeted oxidation state. However, fitting of the EXAFS region using the zirconolite-2M structural model was consistent with In3+ cations accommodated within the Ti4+ site, contrary to the targeted substitution scheme. When deploying U as a surrogate for immobilised Pu in the Ca1-xUxZrTi2-2xIn2xO7 solid solution, it was demonstrated that, for both x = 0.05 and 0.10, In3+ was successfully able to stabilise zirconolite-2M when U was distributed predominantly as both U4+ and average U5+, when synthesised under argon and air, respectively, determined by U L3-edge XANES analysis.


Subject(s)
Indium , X-Ray Absorption Spectroscopy , Argon , Oxidation-Reduction
3.
Small ; 19(8): e2206958, 2023 Feb.
Article in English | MEDLINE | ID: mdl-36507596

ABSTRACT

One of the long-standing challenges of current lead-free energy storage ceramics for capacitors is how to improve their comprehensive energy storage properties effectively, that is, to achieve a synergistic improvement in the breakdown strength (Eb ) and the difference between maximum polarization (Pmax ) and remnant polarization (Pr ), making them comparable to those of lead-based capacitor materials. Here, a polymorphic polar nanoregions (PNRs) structural design by first introducing 0.06 mol BaTiO3 into Bi0.5 Na0.5 TiO3 is proposed to construct the morphotropic phase boundary with coexisting structures of micrometer-size domains and polymorphic nanodomains, enhance the electric field-induced polarization response (increase Pmax ). Then Sr(Al0.5 Ta0.5 )O3 (SAT)-doped 0.94 Bi0.5 Na0.5 TiO3 -0.06BaTiO3 (BNBT) energy storage ceramics with polymorphic PNRs structures are synthesized following the guidance of phase-field simulation and rational composition design (decrease Pr ). Finally, a large recoverable energy density (Wrec ) of 8.33 J cm-3 and a high energy efficiency (η) of 90.8% under 555 kV cm-1 are obtained in the 0.85BNBT-0.15SAT ceramic prepared by repeated rolling process method (enhance Eb ), superior to most practical lead-free competitors increased consideration of the stability of temperature (a variation <±6.2%) and frequency (Wrec > 5.0  cm-3 , η > 90%) at 400 kV cm-1 . This strategy provides a new conception for the design of other-based multifunctional energy storage dielectrics.

4.
Nanoscale Adv ; 4(11): 2468-2478, 2022 May 31.
Article in English | MEDLINE | ID: mdl-36134132

ABSTRACT

Low-dimensional high-entropy materials, such as nanoparticles and two-dimensional (2D) layers, have great potential for catalysis and energy applications. However, it is still challenging to synthesize 2D layered high-entropy materials through a bottom-up soft chemistry method, due to the difficulty of mixing and assembling multiple elements in 2D layers. Here, we report a simple polyol process for the synthesis of a series of 2D layered high-entropy transition metal (Co, Cr, Fe, Mn, Ni, and Zn) hydroxides (HEHs), involving the hydrolysis and inorganic polymerization of metal-containing species in ethylene glycol media. The as-synthesized HEHs demonstrate 2D layered structures with interlayer distances ranging from 0.860 to 0.987 nm and homogeneous elemental distribution of designed equimolar stoichiometry in the layers. These 2D HEHs exhibit a low overpotential of 275 mV at 10 mA cm-2 in a 0.1 M KOH electrolyte for the oxygen evolution reaction. Superparamagnetic spinel-type high-entropy nanoparticles can also be obtained by annealing these HEHs. Our polyol approach creates opportunities for synthesizing low-dimensional high-entropy materials with promising properties and applications.

5.
Inorg Chem ; 61(15): 5744-5756, 2022 Apr 18.
Article in English | MEDLINE | ID: mdl-35377149

ABSTRACT

Zirconolite is considered to be a suitable wasteform material for the immobilization of Pu and other minor actinide species produced through advanced nuclear separations. Here, we present a comprehensive investigation of Dy3+ incorporation within the self-charge balancing zirconolite Ca1-xZr1-xDy2xTi2O7 solid solution, with the view to simulate trivalent minor actinide immobilization. Compositions in the substitution range 0.10 ≤ x ≤ 1.00 (Δx = 0.10) were fabricated by a conventional mixed oxide synthesis, with a two-step sintering regime at 1400 °C in air for 48 h. Three distinct coexisting phase fields were identified, with single-phase zirconolite-2M identified only for x = 0.10. A structural transformation from zirconolite-2M to zirconolite-4M occurred in the range 0.20 ≤ x ≤ 0.30, while a mixed-phase assemblage of zirconolite-4M and cubic pyrochlore was evident at Dy concentrations 0.40 ≤ x ≤ 0.50. Compositions for which x ≥ 0.60 were consistent with single-phase pyrochlore. The formation of zirconolite-4M and pyrochlore polytype phases, with increasing Dy content, was confirmed by high-resolution transmission electron microscopy, coupled with selected area electron diffraction. Analysis of the Dy L3-edge XANES region confirmed that Dy was present uniformly as Dy3+, remaining analogous to Am3+. Fitting of the EXAFS region was consistent with Dy3+ cations distributed across both Ca2+ and Zr4+ sites in both zirconolite-2M and 4M, in agreement with the targeted self-compensating substitution scheme, whereas Dy3+ was 8-fold coordinated in the pyrochlore structure. The observed phase fields were contextualized within the existing literature, demonstrating that phase transitions in CaZrTi2O7-REE3+Ti2O7 binary solid solutions are fundamentally controlled by the ratio of ionic radius of REE3+ cations.

6.
J Nanobiotechnology ; 19(1): 268, 2021 Sep 06.
Article in English | MEDLINE | ID: mdl-34488792

ABSTRACT

BACKGROUND: Tumor-associated macrophages (TAMs) are the most abundant stromal cells in the tumor microenvironment. Turning the TAMs against their host tumor cells is an intriguing therapeutic strategy particularly attractive for patients with immunologically "cold" tumors. This concept was mechanistically demonstrated on in vitro human and murine lung cancer cells and their corresponding TAM models through combinatorial use of nanodiamond-doxorubicin conjugates (Nano-DOX) and a PD-L1 blocking agent BMS-1. Nano-DOX are an agent previously proved to be able to stimulate tumor cells' immunogenicity and thereby reactivate the TAMs into the anti-tumor M1 phenotype. RESULTS: Nano-DOX were first shown to stimulate the tumor cells and the TAMs to release the cytokine HMGB1 which, regardless of its source, acted through the RAGE/NF-κB pathway to induce PD-L1 in the tumor cells and PD-L1/PD-1 in the TAMs. Interestingly, Nano-DOX also induced NF-κB-dependent RAGE expression in the tumor cells and thus reinforced HMGB1's action thereon. Then, BMS-1 was shown to enhance Nano-DOX-stimulated M1-type activation of TAMs both by blocking Nano-DOX-induced PD-L1 in the TAMs and by blocking tumor cell PD-L1 ligation with TAM PD-1. The TAMs with enhanced M1-type repolarization both killed the tumor cells and suppressed their growth. BMS-1 could also potentiate Nano-DOX's action to suppress tumor cell growth via blocking of Nano-DOX-induced PD-L1 therein. Finally, Nano-DOX and BMS-1 achieved synergistic therapeutic efficacy against in vivo tumor grafts in a TAM-dependent manner. CONCLUSIONS: PD-L1/PD-1 upregulation mediated by autocrine and paracrine activation of the HMGB1/RAGE/NF-κB signaling is a key response of lung cancer cells and their TAMs to stress, which can be induced by Nano-DOX. Blockade of Nano-DOX-induced PD-L1, both in the cancer cells and the TAMs, achieves enhanced activation of TAM-mediated anti-tumor response.


Subject(s)
B7-H1 Antigen/drug effects , Doxorubicin/pharmacology , Immune Checkpoint Inhibitors/pharmacology , Nanodiamonds/chemistry , Tumor-Associated Macrophages , A549 Cells , Animals , B7-H1 Antigen/genetics , Cell Line, Tumor , Cytokines/metabolism , Female , Humans , Lung Neoplasms/drug therapy , Mice , Mice, Inbred BALB C , Mice, Nude , Tumor Microenvironment/drug effects
7.
ACS Appl Mater Interfaces ; 13(39): 46866-46874, 2021 Oct 06.
Article in English | MEDLINE | ID: mdl-34559512

ABSTRACT

Transparent material has been widely used in product design and has seen a large increase in its use. In this paper, a kind of aesthetically decorative 5 GHz Wi-Fi dielectric resonator antenna (DRA) of aluminum oxynitride (AlON) transparent ceramic has been designed. High-quality-factor AlON transparent dielectric ceramics were fabricated by presintering at 1780 °C and further cold isostatic pressing (CIP) under a 200 MPa argon atmosphere. For a 9.0 mm thick specimen, the in-line light transmittance reached 83%. Optimum dielectric constant (εr = 9.32), quality factor (Qf = 47 960) and temperature coefficient (TCF = -51.7 ppm/°C) was achieved in the AlON transparent ceramic by cold isostatic pressing. As a result, the proposed aesthetically decorative DRA can achieve an impedance bandwidth of 32% (4.48-6.19 GHz), a high radiation efficiency of 85%, and a low cross-polarization discrimination (XPD) of -30 dB. To achieve a broad bandwidth, the proposed antenna was excited in its dominant TE111x mode and higher-order TE113x mode. The proposed antenna is thus an excellent candidate for an indoor decoration Wi-Fi antenna.

8.
Int J Pharm ; 606: 120872, 2021 Sep 05.
Article in English | MEDLINE | ID: mdl-34246743

ABSTRACT

Doxorubicin (DOX) has been widely incorporated in various delivery forms for tareted treatment of malignant tumors such as triple-negative breast cancer (TNBC), with numerous studies reporting higher therapeutic efficacy and lower toxicity at the same time. However, little attention has been paid to whether DOX in a delivery form acts with the same actions and processes as in free form at the cellular level. This question was investigated in the present study wherein DOX conjugated with polyglycerol-coated nanodiamonds through the pH-sensitive hydrazone bond (Nano-DOX) was compared with DOX in free form on the 4T1 mouse TNBC model. We first found Nano-DOX to have a distinct intracellular distribution profile from DOX. Internalized Nano-DOX mainly stayed in the lysosomes slowly releasing DOX into the cytoplasm and then the nucleus whereas DOX displayed both nuclear and lysosomal distribution after cell uptake. Next, Nano-DOX was shown to induce endoplasmic reticulum (ER) stress without substantial DNA damage while DOX caused massive DNA damage as well as ER stress. Consequently, Nano-DOX only caused minimal activation of pro-inflammatory signaling mediated by MAPK/ERK, NF-κB and STAT3 as seen in response to DOX-inflicted DNA damage. Consistently, DOX-induced activities of ABC transporters, CXCL-1, GM-CSF and IL-6, which are tumor protective events downstream to the pro-inflammatory signaling, were also minimal in Nano-DOX-treated cancer cells. These findings are compelling proof that a chemotherapy in nano form can have distinct intracellular pharmacokinetics from its free from, which can result in altered cellular effects of the drug. Implications of these findings are discussed with an emphasis on nano-drug design, tumor pharmacology and chemoresistance.


Subject(s)
Nanodiamonds , Triple Negative Breast Neoplasms , Animals , Cell Line, Tumor , Doxorubicin , Humans , Hydrazones , Mice
9.
J Hazard Mater ; 415: 125596, 2021 Aug 05.
Article in English | MEDLINE | ID: mdl-33725552

ABSTRACT

The sustainable development of civil nuclear energy requires the fabrication of the durable nuclear wasteforms, in particular for high-level radioactive waste, which involves the design of the composition and microstructure. Herein, we demonstrated that high-entropy ceramics (Eu1-xGdx)2(Ti0.2Zr0.2Hf0.2Nb0.2Ce0.2)2O7 are the potential candidate as immobilizing hosts for high-level radioactive waste. The static aqueous leaching test indicates that the normalized leaching rates for the simulated radionuclides Ce (LRCe) and Gd (LRGd) in as-prepared high-entropy ceramics are approximately 10-6~10-8 g·m-2·d-1 after 42 days testing, much lower than those reported values in doped-Gd2Zr2O7 (10-6~10-3 g·m-2·d-1). The excellent chemical durability is mainly due to the synergistic effects of the compositional complexity and severe lattice distortion. Compared to their ternary oxides, the low oxygen vacancy concentration slows down the migration and diffusion of cations. Moreover, the lattice distortion increases the lattice potential energy, also inhibiting the migration of cations. This study provides a strategy for the development and application of high-entropy ceramics as the wasteforms.

10.
Inorg Chem ; 60(4): 2553-2562, 2021 Feb 15.
Article in English | MEDLINE | ID: mdl-33491452

ABSTRACT

Low-temperature soft chemical synthesis routes to transition-metal nitrides are of interest as an alternative to conventional high-temperature ammonolysis reactions involving large volumes of chemotoxic NH3 gas. One such method is the reaction between metal oxides and NaNH2 at ca. 200 °C to yield the counterpart nitrides; however, there remains uncertainty regarding the reaction mechanism and product phase assemblage (in particular, noncrystalline components). Here, we extend the chemical tool box and mechanistic understanding of such reactions, demonstrating the nitridation of Fe3O4 by reaction with NaNH2 at 170-190 °C, via a pseudomorphic reaction. The more reduced Fe3O4 precursor enabled nitride formation at lower temperatures than the previously reported equivalent reaction with Fe2O3. The product phase assemblage, characterized by X-ray diffraction, thermogravimetric analysis, and 57Fe Mössbauer spectroscopy, comprised 49-59 mol % ε-Fe2+xN, accompanied by 29-39 mol % FeO1-xNx and 8-14 mol % γ″-FeN. The oxynitride phase was apparently noncrystalline in the recovered product but could be crystallized by heating at 180 °C. Although synthesis of transition-metal nitrides is achieved by reaction of the counterpart oxide with NaNH2, it is evident from this investigation that the product phase assemblage may be complex, which could prove a limitation if the objective is to produce a single-phase product with well-defined electrical, magnetic, or other physical properties for applications. However, the significant yield of the FeO1-xNx oxynitride phase identified in this study opens the possibility for the synthesis of metastable oxynitride phases in high yield, by reaction of a metal oxide substrate with NaNH2, with either careful control of H2O concentration in the system or postsynthetic hydrolysis and crystallization.

11.
Inorg Chem ; 59(24): 18407-18419, 2020 Dec 21.
Article in English | MEDLINE | ID: mdl-33296192

ABSTRACT

The synthesis, structure, and thermal stability of the periodate double perovskites A2NaIO6 (A= Ba, Sr, Ca) were investigated in the context of potential application for the immobilization of radioiodine. A combination of X-ray diffraction and neutron diffraction, Raman spectroscopy, and DFT simulations were applied to determine accurate crystal structures of these compounds and understand their relative stability. The compounds were found to exhibit rock-salt ordering of Na and I on the perovskite B-site; Ba2NaIO6 was found to adopt the Fm-3m aristotype structure, whereas Sr2NaIO6 and Ca2NaIO6 adopt the P21/n hettotype structure, characterized by cooperative octahedral tilting. DFT simulations determined the Fm-3m and P21/n structures of Ba2NaIO6 to be energetically degenerate at room temperature, whereas diffraction and spectroscopy data evidence only the presence of the Fm-3m phase at room temperature, which may imply an incipient phase transition for this compound. The periodate double perovskites were found to exhibit remarkable thermal stability, with Ba2NaIO6 only decomposing above 1050 °C in air, which is apparently the highest recorded decomposition temperature so far recorded for any iodine bearing compound. As such, these compounds offer some potential for application in the immobilization of iodine-129, from nuclear fuel reprocessing, with an iodine incorporation rate of 25-40 wt%. The synthesis of these compounds, elaborated here, is also compatible with both current conventional and future advanced processes for iodine recovery from the dissolver off-gas.

12.
Int J Mol Sci ; 20(19)2019 Sep 27.
Article in English | MEDLINE | ID: mdl-31569691

ABSTRACT

Xanthones are important chemical constituents of Garcinia xanthochymus and varied bioactivities including cytotoxicity. However, their anti-tumor mechanism has remained unknown. Here, we isolated and identified a new xanthone named garciniaxanthone I (1) and five known compounds from the bark of G. xanthochymus. Their structures were elucidated by NMR analysis and HRESIMS. The anti-proliferation activities of all isolated compounds were evaluated on four human tumor cell lines (HepG2, A549, SGC7901, MCF-7). The results demonstrated that the anti-proliferation activity of xanthone was related to the number and location of prenyl groups. We further found that garciniaxanthone I (GXI) could induce HepG2 apoptosis and enhance the expression of cleaved caspase-8, caspase-9, and caspase-3. GXI could also increase Bax level and concurrently reduce the overexpression of Bcl-2, Bcl-XL, Mcl-1, and surviving in HepG2 cells. Moreover, GXI could inhibit cell migration of HepG2 cells by inhibiting the expressions of MMP-7 and MMP-9. In summary, our study suggests that GXI could induce HepG2 apoptosis via the mitochondrial pathway and might become a lead compound for liver cancer treatment.


Subject(s)
Antineoplastic Agents, Phytogenic/pharmacology , Apoptosis/drug effects , Garcinia/chemistry , Mitochondria/drug effects , Plant Bark/chemistry , Plant Extracts/pharmacology , Xanthones/pharmacology , Antineoplastic Agents, Phytogenic/chemistry , Antineoplastic Agents, Phytogenic/isolation & purification , Cell Line, Tumor , Cell Proliferation/drug effects , Humans , Magnetic Resonance Spectroscopy , Mitochondria/metabolism , Molecular Structure , Plant Extracts/chemistry , Plant Extracts/isolation & purification , Signal Transduction/drug effects , Xanthones/chemistry , Xanthones/isolation & purification
13.
Environ Sci Pollut Res Int ; 26(8): 7476-7485, 2019 Mar.
Article in English | MEDLINE | ID: mdl-30659484

ABSTRACT

Sediment resuspension has been recognized as a crucial internal process in aquatic ecosystems. However, there is still a lack of reliable measuring methods due to the complex hydrodynamic conditions in large shallow eutrophic lakes. In this study, sequential sediment traps (SST) and instantaneous multiple point (IMP) methods were compared at 6 sites located in the littoral zone of Zhushan Bay in Lake Taihu. Results show that the average resuspension rates (RRs) estimated using the IMP method at sites 1 to 6 were 266.39, 272.79, 235.17, 254.95, 392.25, and 483.85 g·m-2d-1, respectively. While the RRs estimated using the SST method were 195.16, 236.99, 116.76, 156.23, 389.53, and 509.85 g·m-2d-1, respectively. In wind-disturbed areas, both methods were suitable for RR analysis in large and shallow eutrophic lakes and SST provides high-resolution temporal RR estimations. However, in the areas with cyanobacterial blooms and vegetation cover, the IMP method overestimated the RR. Therefore, SST was more suitable across different conditions in large and shallow eutrophic lakes, providing a simple, accurate, and high-resolution temporal estimation of RR, while furthering our understanding of lake evolution processes.


Subject(s)
Environmental Monitoring , Geologic Sediments/analysis , Lakes/chemistry , Wind , China , Ecosystem , Ecotype , Eutrophication , Hydrodynamics
14.
Zhongguo Zhen Jiu ; 37(6): 571-575, 2017 Jun 12.
Article in Chinese | MEDLINE | ID: mdl-29231494

ABSTRACT

OBJECTIVE: To study the primary and secondary factors of the allergic history, the frequency of acupoint application and the time of acupoint application in the treatment of bronchial asthma and optimize its scheme. METHODS: Eighty patients of bronchial asthma were selected as the subjects in the orthogonal trial. The herbal medicines were the empirical formula of acupoint application (prepared at the ratio as 2:2:1:1:1:1:1:1:1 of semen brassicae, rhizome corydalis, unprocessed radix kansui, asarum sieboldii, ephedra, semen lepidii, syzygium aromaticum, cortex cinnamomi and fructus gleditsiae) and used on bilateral Feishu (BL 13), Xinshu (BL 15), Geshu (BL 17) and Shenshu (BL 23). Firstly, two groups were divided according to allergic history (40 cases with allergic history and 40 cases without allergic history), and then four subgroups were divided on the basis of the two main groups, 10 cases in each one. Through studying three factors and two levels, i.e. allergic history (Factor A:AⅠ:with allergic history; AⅡ:without allergic history), the frequency of acupoint application (Factor B:BⅠ:4 times; BⅡ:10 times, in which, in the group of 4-time applications, the application was given once every 10 days; in the group of 10-time applications, the application was given once every 4 days); and the time of application (Factor C:CⅠ:4 h; CⅡ:8 h), the optimal scheme was screened on the basis of the attack frequency before and after treatment and the score of the asthma quality life questionnaire (AQLQ) before treatment and 6 months after treatment in the patients of each group. RESULTS: ① The orthogonal trial indicated that the best optimal scheme was AⅠBⅡCⅠ, meaning the patients with allergic history were treated with acupoint application for 10 times, remained for 4 h. ②Factor B (frequency of acupoint application) and C (time of acpoint application) were the significant influential factors of AQLQ scores (both P<0.05). ③The comparison of the attack frequency and AQLQ score before and after treatment in all of the patients showed that the different combinations of factor levels induced the different impacts on the asthma attack frequency and AQLQ scores. Except in the group No.1 and the group No.5, the improvements were all significant in the rest groups, indicating the significant differences (P<0.05, P<0.01). CONCLUSIONS: Acupoint application reduces apparently the attack frequency of asthma in the patients and improves the living quality. The primary and secondary relationship among the allergic history, the frequency of acupoint application and the time of acupoint application for the impacts on the therapeutic effects are:the frequency of acupoint application > the time of acupoint application > the allergic history. The best optimal scheme is AⅠBⅡCⅠ, meaning the patients with allergic history are treated with acupoint application for 10 times, remained for 4h.


Subject(s)
Acupuncture Points , Asthma/therapy , Acupuncture Therapy/methods , Humans , Phytotherapy/methods
15.
Bioorg Med Chem ; 25(24): 6605-6613, 2017 12 15.
Article in English | MEDLINE | ID: mdl-29128163

ABSTRACT

Garcinia xanthochymus is a widely used folk medicine in southwestern China. Previous studies indicated it possesses potential anti-diabetic activities both in vitro (Fu et al., 2014; Nguyen et al., 2017) and in vivo (Shivanand et al., 2017). To discover bioactive ingredients from it and unveil their mechanism of action against diabetes, the present study was designed to isolate constituents from extract of G. xanthochymus, determine their structures, screen their activities and investigate mechanism of action of the active substances. Twenty compounds including a new depsidone named garciniadepsidone A (20) and 19 known xanthones were obtained. All of them were screened to discover the active compounds with anti-diabetic activities. Finally, three xanthones including 12b-hydroxy-des-d-garcigerrin (5), 1,2,5,6-tretrahydroxy-4-(1,1-dimethyl-2-propenyl)-7-(3-methyl-2-butenyl) xanthone (13) and 1,5,6-trihydroxy-7,8-di(3-methyl-2-butenyl)-6',6'-dimethylpyrano (2',3':3,4) xanthone (18) were found to be able to significantly stimulate the glucose uptake in the skeleton muscle cells. The effects of the three compounds were comparable to those of insulin and metformin. Based on molecular mechanistic study, it was found that both of compound 5 and 13 promoted glucose uptake by activating phosphatidylinositol-3 kinase (PI3K)/the serine/threonine kinase protein kinase B (PKB/Akt) signaling pathway and AMP-activated protein kinase (AMPK) signaling pathway, resulting in the translocation of GLUT4 in L6 myotubes without affecting the expression of GLUT4. Compound 5 and 13 have great potential to be developed as promising leads to target diabetes.


Subject(s)
Depsides/pharmacology , Garcinia/chemistry , Glucose/metabolism , Hypoglycemic Agents/pharmacology , Lactones/pharmacology , Muscle Fibers, Skeletal/drug effects , Xanthones/pharmacology , Animals , Cell Survival/drug effects , Cells, Cultured , Depsides/chemistry , Depsides/isolation & purification , Dose-Response Relationship, Drug , Hypoglycemic Agents/chemistry , Hypoglycemic Agents/isolation & purification , Lactones/chemistry , Lactones/isolation & purification , Molecular Structure , Muscle Fibers, Skeletal/cytology , Rats , Structure-Activity Relationship , Xanthones/chemistry , Xanthones/isolation & purification
16.
Article in English | MEDLINE | ID: mdl-28628836

ABSTRACT

Aqueous two-phase micellar system (ATPMS), as an alternative liquid-liquid extraction technique, has been extensively exploited for the precise separation or large-scale concentration of biomolecules. In this article, a novel affinity-based ATPMS composed of mixed micelles was constructed by introducing a Copper-chelated Triton X-114 (TX-Cu(II)) into an aqueous solution of hydrophobically modified ethylene oxide polymer (HM-EO). Phase diagram of the HM-EO/TX-Cu(II) system was measured, and the partitioning behavior of model proteins (YND, BSA, lysozyme) were studied by using this new system. The addition of HM-EO can result in formation of the micellar network in the micelle-rich phase, making the phase separation easier and stabler. In addition, the extractive performance of ATPMS was enhanced due to the existence of the mixed micelles composed by HM-EO and Cu(II)-chelated TX. It was found in the partitioning experiments that the hexahistidine-tagged Yeast 3',5'-bisphosphate nucleotidase (YND) was selectively extracted into the micelle-rich phase, while the histidine-poor proteins (BSA and lysozyme) remained in the micelle-poor phase. Finally, HM-EO/TX-Cu(II) was used directly to process the fermentation broth. The target protein, YND could be recovered from the cell lysate with a recovery yield of 49.23% and purification factor of 2.63. The results indicated that the new affinity-based HM-EO/TX-Cu(II) system had high partitioning performance which is promising for effectively separation of the histidine-tagged proteins.


Subject(s)
Fungal Proteins/isolation & purification , Micelles , Nucleotidases/isolation & purification , Yeasts/enzymology , Chromatography, High Pressure Liquid , Ethylene Oxide , Fungal Proteins/analysis , Liquid-Liquid Extraction , Mass Spectrometry , Nucleotidases/analysis
17.
Sensors (Basel) ; 16(6)2016 Jun 22.
Article in English | MEDLINE | ID: mdl-27338417

ABSTRACT

Target tracking is a critical wireless sensor application, which involves signal and information processing technologies. In conventional target position estimation methods, an estimate is usually demonstrated by an average target position. In contrast, this work proposes a distributed information compression method to describe the measurement uncertainty of tracking problems in cluster-based wireless sensor networks. The leader-based information processing scheme is applied to perform target positioning and energy conservation. A two-level hierarchical network topology is adopted for energy-efficient target tracking with information compression. A Level 1 network architecture is a cluster-based network topology for managing network operations. A Level 2 network architecture is an event-based and leader-based topology, utilizing the concept of information compression to process the estimates of sensor nodes. The simulation results show that compared to conventional schemes, the proposed data processing scheme has a balanced system performance in terms of tracking accuracy, data size for transmission and energy consumption.

18.
Zhong Yao Cai ; 39(4): 743-6, 2016 Apr.
Article in English | MEDLINE | ID: mdl-30132313

ABSTRACT

Objective: To explore the application of 3S techniques to regional survey of Chinese materia medica resources, in order to provide technical reference for the fourth national survey of Chinese materia medica resources. Methods: Based on remote sensing technology, satellite positioning technology and GIS technology, GPS position indicator, SLR camera and related software such as Google Earth, HOLUX ez Tour for Logger and XTTools were used to establish the application model of 3S techniques for the regional survey of Chinese materia medica resources. Results: The application model established in field survey performed well in pathway expedition and sample plot survey. It also matched the digital images of Chinese herbs with their geographic information efficiently and did statistical analysis effectively on survey result. Conclusion: It is suggested that the application of 3S techniques to regional survey of Chinese meteria medica resources is beneficial to improve efficiency of the survey and obtain more accurate geographic information for sharing and dynamic monitoring.


Subject(s)
Materia Medica , Drugs, Chinese Herbal , Medicine, Chinese Traditional , Research Design , Surveys and Questionnaires
19.
Huan Jing Ke Xue ; 35(6): 2241-8, 2014 Jun.
Article in Chinese | MEDLINE | ID: mdl-25158502

ABSTRACT

Sludge flocs morphology and effluent qualities of nonwoven bioreactor during filamentous bulking and normal sludge status were compared. Flux variations, analysis of filtration resistances and extracellular polymer substances (EPS) contents during filamentous bulking and normal sludge status were studied. The results showed that the average particle size of bulking sludge flocs and normal sludge flocs was 448.6 microm and 234.8 microm, respectively. During the bulking sludge status, the average COD and NH4(+) -N removal rate and effluent turbidity were 90.1%, 93.1% and 1.33 NTU, respectively, compared with 91.4% , 97.0% and 0.99 NTU during the normal sludge status. Filamentous bulking had little impact on COD removal, while it inhibited NH4(+) -N removal to a certain extent and had slight impact on effluent turbidity. Average membrane flux decay rates during the bulking sludge status and the normal sludge status were 3.29 L x (m2 x h2)(-1) and 4.87 L x (m2 x h2)(-1), respectively, and the fouling during bulking sludge status was slighter. Reversible fouling was the main fouling when sludge was bulking while irreversible fouling was the main fouling when the sludge was in normal status. The prior occurrence of reversible fouling could reduce irreversible fouling therefore slow down the flux decline. Soluble microbial products (SMP) contents in normal sludge mixed liquid and bulking sludge mixed liquid were 21.369 mg x L(-1) and 10.182 mg x L(-1), respectively, protein/polysaccharide (P/C) was 0.370 and 0.497, respectively, SMP gross was related to fouling resistance and P/C was associated with reversible fouling proportion. The relation between loosely bound EPS in mixed liquid sludge and membrane fouling was similar to SMP. Sludge with more EPS could accumulate on membrane more easily, and the EPS that accumulated on membrane was mainly protein. EPS gross in mixed liquid sludge, EPS in membrane surface sludge and their P/C all had positive correlations to reversible fouling.


Subject(s)
Bioreactors , Particle Size , Sewage , Waste Disposal, Fluid/methods , Filtration , Polymers/chemistry , Polysaccharides/analysis , Proteins/analysis
20.
Zhonghua Wei Chang Wai Ke Za Zhi ; 15(12): 1227-31, 2012 Dec.
Article in Chinese | MEDLINE | ID: mdl-23268265

ABSTRACT

OBJECTIVE: To explore the diagnostic value of combined modified Alvarado scores (MAS) and computed tomography imaging in the pathological types of acute appendicitis in adults. METHODS: Clinical data of a total of 396 adult patients with acute appendicitis confirmed by surgery and pathology were analyzed retrospectively from June 2007 to July 2010. Case-control study was used to investigate the MAS. CT signs were studied in 115 patients who underwent preoperative CT scan. Univariable analysis was performed using each indicator among different pathological types. Discriminant classification was formed by applying significant variables identified from univariable analysis and a Fisher discriminant function was created. RESULTS: Twenty three variables were statistically significant among different pathological types after univariable analysis(P<0.05) and were selected for discriminant analysis. Six variables including temperature(X1), leucocyte count(X2), the proportion of neutrophil(X3), MAS points(X4), periappendiceal fat stranding(X5), and extraluminal air(X6) were enrolled. The discriminant function equation was Y1=0.012X1+0.041X2+0.069X3-0.039X4+2.653X5+1.418X6, Y2=0.327X1+0.041X2-0.034X3-0.140X4-1.114X5+2.982X6. The accuracy was 76.5%(88/115) in retrospective assessment and 77.8%(21/27) in prospective assessment. CONCLUSION: The combined use of MAS and CT imaging signs is useful in identifying the pathological types of acute appendicitis in adults, so it is helpful in choosing reasonable therapeutic option for surgeons.


Subject(s)
Appendicitis/diagnosis , Acute Disease , Case-Control Studies , Humans , Retrospective Studies , Sensitivity and Specificity , Tomography, X-Ray Computed
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