查找使用阿拉丁产品的科研文献

Micelles self-assembled by 3-O-β-d-glucopyranosyl latycodigenin enhance cell membrane permeability, promote antibiotic pulmonary targeting and improve anti-infective efficacy

Zhang Man,Ye Lili,Huang Hao,Cheng Dandan,Liu Kaixin,Wu Wenbo,Shen Fukui,Jiang Zhihong,Hou Yuanyuan,Bai Gang

Background Nanoparticle-based pulmonary drug delivery systems are commonly developed and applied for drug-targeted delivery. They exhibit significant advantages compared to traditional pulmonary drug delivery systems. However, developing the formulation of each drug is a time-consuming and laborious task.Results In this study, a universal lung-targeting nanoparticle was designed and constructed. The self-assembled micelles were composed of a platycodon secondary saponin, 3-O-β-d-glucopyranosyl platycodigenin 682 (GP-682), based on its specific amphiphilic structure. The GP-682 micelles exhibited a relatively stable zeta potential with a particle size between 60 and 90 nm, and the critical micelle concentration (CMC) value was approximately 42.3 μg/mL. Preincubation of GP-682 micelles markedly enhanced their cell membrane permeability and improved drug uptake in vitro. The results were visualized using fluorescent dye tracing, transmission electron microscopy (TEM) observations and the lactate dehydrogenase (LDH) release assay. The obtained benefits enhanced the distribution of levofloxacin (Lev) in mouse lung tissue and reduced antibiotics overdosing. The acute lung injury mouse model induced by the Pseudomonas aeruginosa PA 14 strain demonstrated that preinjection of GP-682 micelles before antibiotic administration resulted in a higher survival rate and anti-infective efficacy in vivo. It also caused reductions in pulmonary injury, bacterial invasion and cytokine expression compared with treatment with Lev alone.Conclusion sGP-682 micelles are another nanoparticle-based pulmonary drug delivery system and provide a new lung-targeting therapy option.

Two-stage biosynthesis of D-tagatose from milk whey powder by an engineered Escherichia coli strain expressing L-arabinose isomerase from Lactobacillus plantarum

Guoyan Zhang,Hossain M. Zabed,Junhua Yun,Jiao Yuan,Yufei Zhang,Yang Wang,Xianghui Qi

In this study, a new strain of Lactobacillus plantarum (CY.6) was identified and its L-arabinose isomerase (L-AI) encoding gene ( ara A) was overexpressed in Escherichia coli BL21 for the biosynthesis of D-tagatose from milk whey powders (WP). Whole-cell biotransformation of lactose in WP into D-tagatose was done by three technological approaches, including 100%, 50% and 0% hydrolysis of lactose in WP before biotransformation, where simultaneous saccharification and biotransformation (SSB, 0% prior hydrolysis of lactose) produced maximum amounts of D-tagatose. Two-stage SSB provided 73.6% conversion efficiency (based on D-galactose) and 36.8% (in term of lactose), with 51.5 g/L of D-tagatose after 96 h, while concentration of D-tagatose produced after first stage was 34.4 g/L. Yield and volumetric productivity of D-tagatose after two-stage SSB were found to be 0.26 g/g of WP (0.37 g/g of lactose, 0.74 g/g of D-galactose produced from lactose) and 0.54 g/L/h, respectively.

Facile fabrication of recyclable and macroscopic D-g-C3N4/sodium alginates/non-woven fabric immobilized photocatalysts with enhanced photocatalytic activity and antibacterial performance

Huo Kaili,Wang Jin,Zhuang Tao,Zhao Yuqiang,Gao Boru,Dou Mengmeng,Wang Xiaoyue,Fu Yao,Wang Dongying,Ci Lin

The immobilization of catalysts hinders the application of nanosized photocatalysts in wastewater treatment. In this study, a simple method for the preparation of flexible composite non-woven catalysts with a good spectral response is presented. Firstly, the porous g-C 3 N 4 nanosheets containing nitrogen defects (DCN) and sodium alginate (SA) were blended to prepare the casting solution and then coated on the surface of polyester and viscose blend non-woven fabric (NW). Finally, the robust three-dimensional composite non-woven catalyst (DCN@SA/NW) was constructed by cross-linking with CaCl 2 . The as-prepared samples were characterized by different physicochemical techniques including SEM, EDS, FTIR, Raman, XRD, XPS, and TGA. The photocatalytic degradation of dyes and antibiotics and self-cleaning and antibacterial properties of the catalyst were investigated. The optimal DCN@SA/NW formulation was 2.0 wt.% DCN and 2.0 wt.% SA. The DCN@SA/NW composite efficiently degraded rhodamine (RhB) and tetracycline hydrochloride (TC). Moreover, the synthesized non-woven composite catalyst was easily recycled and remained stable, indicating its promising potential in wastewater treatment. The DCN@SA/NW also exhibited outstanding self-cleaning and antibacterial performance. This study provides an interesting idea for the research and development of immobilized photocatalysts and has great potential in future practical photocatalytic applications.

Isoliquiritigenin alleviates LPS/ D-GalN-induced acute liver failure by activating the PGC-1α/ Nrf2 pathway to reduce oxidative stress and inflammatory response

Lu Wang,Xiaohui Wang,Lina Kong,Shuyuan Wang,Kai Huang,Jingjing Wu,Changyuan Wang,Huijun Sun,Kexin Liu,Qiang Meng

Acute liver failure (ALF) is a dramatic liver disease characterized by large areas of inflammation. However, there are no available effective targeted drugs for ALF treatment. In the study, serum biochemical index and H&E were used to explore the amelioration of the liver histopathological changes. The oxidative stress kits, quantitative real-time PCR, western blot, immunohistochemistry, immunofluorescence staining, reactive oxygen species (ROS), and siRNA were used to elucidate the mechanisms underlying isoliquiritigenin (ISL) protection. The results showed that ISL significantly improved the liver pathological changes. Furthermore, ISL reduced oxidative stress by altering the expression of PGC-1α, Nrf2, HO-1, NQO1, Keap1, GCLC, and GCLM in damaged hepatocytes. Moreover, the levels of inflammation-related genes including NLRP3 inflammasome, IL-1β, IL-6, TNF-α, iNOS, and Mip-2 were repressed by ISL. In addition, ISL alleviated LPS/D-GalN-induced hepatocytes apoptosis by increasing the Bcl-2/Bax ratio and suppressing the expression of cleaved caspase-3. Further in vivo and in vitro evidence proved the involvement of the PGC-1α/Nrf2 signaling pathway in ISL protection. In conclusion, ISL improves the ability of anti-oxidative stress, alleviates inflammatory reaction, apoptosis, and inhibits NLRP3 inflammasome to protect lipopolysaccharide/D-galactosamine (LPS/D-GalN)-induced ALF through activating the PGC-1α/Nrf2 pathway, which provides the possibility for the treatment of ALF.

Well-ordered chitin whiskers layer with high stability on the surface of poly(d,l-lactide) film for enhancing mechanical and osteogenic properties

Wenjun Liu,Ling Zhu,Yunfa Ma,Lihao Ai,Wei Wen,Changren Zhou,Binghong Luo

In order to better utilize and combine the advantages of poly( d , l -lactide) (PDLLA) matrix and natural polysaccharide chitin whiskers (CHWs), needle-like CHWs with chiral nematic liquid crystal characteristics and remarkable moduli were chosen to surface modify PDLLA film. By a vertical coating method, a stable and well-ordered CHWs coating was formed on the surface of the PDLLA film through a polydopamine (PDA) interlayer. The high stability of the well-ordered CHWs coating on the surface of the PDLLA film was confirmed by PBS soaking experiment in terms of the changes of weight and surface morphology of the film. The surface microstructure and composition of the resulting PDLLA-PDA-CHWs film were characterized by field emission scanning electron microscopy (FESEM), atomic force microscope (AFM) and X-ray photoelectron spectroscopy (XPS), and the thickness of the PDLLA, PDA and CHWs layers was determined using FESEM, too. Comparing with traditional PDLLA/CHWs film, prepared by solution blending with optimal content of 5 wt% CHWs, the hydrophilicity and mechanical properties of the PDLLA-PDA-CHWs film were significantly improved owing to the immobilization of a highly ordered CHWs coating. Furthermore, in vitro cell culture showed that the well-ordered CHWs coating had a more significant effect on promoting the adhesion, spreading, proliferation and osteogenic differentiation of MC3T3-E1 cells. All these results showed that the resulting PDLLA-PDA-CHWs film with well-ordered CHWs coating designed through simple and effective approach has promising application in bone repair material field.

Synergistic anti-breast cancer effect of pulsatilla saponin D and camptothecin through interrupting autophagic–lysosomal function and promoting p62-mediated ubiquitinated protein aggregation

Wang Kai,Tu Yanbei,Wan Jian-Bo,Chen Meiwan,He Chengwei

Autophagy is an evolutionarily conserved mechanism to protect the cells from unfavorable environmental conditions. Inhibition of autophagy has been contemplated as a novel strategy to enhance anticancer efficacy of existing chemotherapeutic agents. We previously reported that pulsatilla saponin D (PSD) was a potent autophagy inhibitor. However, its anticancer potential as adjuvant and underlying mechanisms are still unknown. In this study, we identified that PSD induced the formation of autophagosome in MCF-7 and MDA-MB-231 breast cancer cells. However, PSD alone and particularly co-treatment with camptothecin remarkably increased p62 protein levels, indicating that PSD strongly inhibited the autophagic cargo degradation. The mechanistic study indicated that PSD profoundly abolished the co-localization of EGFP-LC3 and lysosomal-specific probe LysoTracker Red, suggesting that the autophagosome–lysosome fusion was blocked by PSD, which is similar to the action of chloroquine. In addition, PSD significantly increased lysosomal pH and inhibited the activation of lysosomal cathepsins in both breast cancer cell lines. Furthermore, the accrued p62 resulted in accumulation of ubiquitinated proteins owing to the interaction with p62 and delivery to the malfunctioned autophagosome by PSD. Finally, we demonstrated that PSD synergistically enhanced the anticancer activity of camptothecin (CPT) in cultured breast cancer cells and in mouse xenograft tumor models. Our results indicated that PSD inhibited autophagic flux via blocking autophagosome–lysosome fusion and lysosomal acidification, which may confer a synergistic anti-breast cancer activity of PSD and CPT.

Rapid determination of 3′, 4′-dimethoxy flavonol-3-β-d-glucopyranoside in rat plasma by LC-MS/MS method followed by protein precipitation

Qiong Lou,Jun Wen,Yuanying Jiang,Jinghua Huang,Guorong Fan,Fenyun Song

A reliable liquid chromatography/tandem mass (LC-MS/MS) method was developed for quantitation of 3′, 4′-dimethoxy flavonol-3-β- d -glucopyranoside (DF3G) in rat plasma using pantoprazole as the internal standard. An Agilent C18 column (100 mm × 3 mm, 3.5 μm) was performed for chromatographic separation with the mobile phase composed of methanol-water (containing formic acid) at a flow rate of 0.4 mL/min. A triple-quadrupole mass spectrometry equipped with an electrospray ionization (ESI) source in positive ion mode was applied to quantitative analysis by multiple reacting monitoring (MRM). The MRM precursor-product ion transition of DF3G and Pantoprazole (IS) were m / z 461.1 → 299.2 and 383.9 → 200.2, respectively. Calibration curves were recovered in a concentration range of 1–500 ng/mL for plasma with a limit of lower quantification (LLOQ) of 1 ng/mL. The intra-day and inter-day precision were not >10%. The accuracy of DF3G ranged from −10% to 0.53% in quality control (QC) samples at three concentrations. DF3G was not degraded during the analysis and the storage period. All the data were validated in accordance with the FDA bioanalytical method validation guideline. The LC-MS/MS method was successfully employed in the pharmacokinetic study of the DF3G after oral administration and intravenous injection in rats.

Small Molecular Weight Aldose (d-Glucose) and Basic Amino Acids (l-Lysine, l-Arginine) Increase the Occurrence of PAHs in Grilled Pork Sausages

Wen Nie,Ke-zhou Cai,Yu-zhu Li,Shuo Zhang,Yu Wang,Jie Guo,Cong-gui Chen,Bao-cai Xu

(1) Background: Amino acids and carbohydrates are widely used as additives in the food industry. These compounds have been proven to be an influencing factor in the production of chemical carcinogenic compounds polycyclic aromatic hydrocarbons (PAHs). However, the effect of the properties of the amino acids and carbohydrates on the production of PAHs is still little known. (2) Methods: We added different (i) R groups (the R group represents an aldehyde group in a glucose molecule or a ketone group in a fructose molecule); (ii) molecular weight carbohydrates; (iii) polarities, and (iv) acid-base amino acids to pork sausages. The effects of the molecular properties of carbohydrates and amino acids on the formation of PAHs in grilled pork sausages were investigated. (3) Results: The results showed that a grilled sausage with aldehyde-basedd-glucose was capable of producing more PAHs than a sausage with keto-basedd-fructose. A higher PAH content was determined in the grilled pork sausage when the smaller molecular weight,d-glucose, was added compared with the sausage where the larger molecular weight, 4-(α-d-glucosido)-d-glucose and cellulose were added. The addition of basic amino acids (l-lysine,l-arginine) was capable of producing more PAHs compared with the addition of acidic amino acids (l-glutamic acid,l-aspartate). When amino acid containing a benzene ring was added, a smaller volume of PAHs was produced compared with the addition of other amino acids. (4) Conclusions: Our study suggests that systematic consideration of molecule properties is necessary when using food additives (amino acids and carbohydrates) for food processing.Keywords:amino acids;carbohydrates;acidity;polarity;molecular weight

A comb-like branched β-d-glucan produced by a Cordyceps sinensis fungus and its protective effect against cyclophosphamide-induced immunosuppression in mice

Ting Hu,Chenbo Jiang,Qilin Huang,Fengyuan Sun

An exopolysaccharide (EPS) was fractionated from fermentation media of a Cordyceps sinensis fungus (Cs-HK1) by ethanol precipitation at 2/5 volume ratio of ethanol/media. Its structural characteristics were elucidated by FT-IR, GC, GC–MS, 1D and 2D NMR combined with periodate oxidation, Smith degradation, partial acid hydrolysis, and methylation analysis. Furthermore, the immunomodulatory activity of EPS was evaluated by the model of cyclophosphamide-induced immunosuppression. The results from monosaccharide composition and partial acid hydrolysis indicated that EPS almost consisted of glucose excluding a trace amount of mannose . GC–MS and NMR analysis further confirmed EPS had a linear backbone of (1→3)-β- d -glucopyranosyl residues with a single (1→6)-β- d -glucopyranosyl side-branching unit for every three β- d -glucopyranosyl residues, showing a comb-like β- d -glucan with short and intensive branches, which was responsible for high viscosity. Moreover, EPS could significantly enhance immune organs and stimulate the release of major cytokines TNF-α and INF-γ, suggesting that EPS exhibited protective effect in immunocompromised mice.

Enhancing the thermal stability of the bulk-heterojunction photovoltaics based on P3HT/PCBM by incorporating diblock amphipathic P3HT–PEO at D/A interface

Jikang Liu,Xiaoguang Zhu,Junli Li,Jiulin Shen,Guoli Tu

A diblock amphipathic copolymer P3HT–PEO was rationally designed and easily synthesized. By introducing P3HT–PEO into P3HT/PCBM blends, the intramolecular interaction between the P3HT–PEO and the donor/acceptor (D/A) molecule in the blends could make the P3HT–PEO located at P3HT/PCBM domains' interface, which could stabilize the morphology of the bulk-heterojunction and also suppress the acceptor PCBM from severe aggregations under prolonged annealing time. By doping only 5 wt% P3HT–PEO, the device-5 (with 5 wt% P3HT–PEO) exhibited a PCE of 3.60% with thermal annealing at 150 °C for 10 min and remained at 3.61% after annealing for 120 min. In contrasted to the device-0 (without P3HT–PEO), the PCE decreased from 3.26% to 1.61% after annealing at 120 min, which also showed lager clusters of PCBM. This finding will inspire new design of additive materials that can control BHJ morphology through to realize highly efficient and thermally stable solar cells.

In vitro and in vivo evaluation of redox-responsive sorafenib carrier nanomicelles synthesized from poly (acryic acid) -cystamine hydrochloride-D-α-tocopherol succinate

Yu Liu,Jia Yang,Xin Wang,Ju Liu,Zhaobo Wang,Hongsheng Liu,Lijiang Chen

End-Functionalized Poly(N-isopropylacrylamide) with d-Glucosamine through Different Initiator from C-1 and C-2 Positions via Atom Transfer Radical Polymerization

Guihua Cui,Zhengguo Gao,Nannan Qiu,Toshifumi Satoh,Toyoji Kakuchi,Qian Duan

Regioselective modification ofd-glucosamine (2-amino-2-deoxy-d-glucopyranose, GA) through C-1 and C-2 positions to synthesized thermo-responsive D-Glucosamine-poly(N-iso-propylacrylamide) (PNIPAM) via atom transfer radical polymerization (ATRP) was investigated for the first time. Two different schemes of the synthesis for GA derivatives (GA-PNIPAM (i) and (ii)) with well-defined structures using 3,4,6-tri-o-acetyl-2-deoxy-2-phthalimido-β-d-glucopyranose and 1,3,4,6-tetra-o-acetyl-2-amino-2-deoxy-β-d-glucopyranose intermediates were examined. The GA-PNIPAM (ii) had an amino at C-2 position, while there was a hydroxyl in GA-PNIPAM (i) at this position. Both the resulting oligomers (i) and (ii) had a narrow dispersity, and no significant cytotoxic response of copolymers (i) and (ii) was observed in the cell line over the concentration range from 0.1 μg/mL to 1000 μg/mL at any of the exposure times. In addition, it was discovered that GA-PNIPAM (i) and (ii) inhibited the proliferation of Human Hepatocellular Carcinoma Cells HepG2 as the concentration and the time changed, and the inhibitory activity of polymer (ii) was higher than that of he (i). The results suggest that the GA-PNIPAM polymers show excellent biocompatibility in vitro.Keywords:poly(N-isopropylacrylamide) (PNIPAM);d-glucosamine (GA);atom transfer radical polymerization (ATRP);lower critical solution temperature (LCST)