JOURNAL OF CHEMICAL THERMODYNAMICS
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2020
·
IF 2.888
Pan Zhang,Mengying Li,Chunjie Lv,Yanjie Zhang,Lemeng Wang,Dong Fu
Piperazine (PZ) was used to enhance the absorption of CO 2 in 2-diethylaminoethanol (DEAE) and 1-dimethylamino-2-propanol (DMA2P) aqueous solutions. The mole fraction of CO 2 in N 2 -balanced gas mixtures ranged from 0.1 to 0.8. The mass fractions of amine and PZ ranged from 0.300 to 0.500 and from 0.050 to 0.075, respectively. The experiments were performed at 313.2 K. The absorption capacity and absorption rate under a series of conditions were illustrated, and the effect of CO 2 partial pressure on the absorption performance was demonstrated. At a given CO 2 partial pressure, the CO 2 absorbed by the PZ promoted DEAE and DMA2P aqueous solutions increases with the mass fraction of the mixed aqueous solutions, and it increases with the CO 2 partial pressure at a given mass fraction. The absorption capacity of the DMA2P-PZ aqueous solution is slightly higher than that of the DEAE-PZ aqueous solution. In addition, the absorption rate depends on the competitive effects of the mass fractions, solution viscosity and the partial pressure of CO 2 .
研究领域:
化学工程
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环境科学
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产品关联
DOI
高影响因子
HISTOCHEMISTRY AND CELL BIOLOGY
·
2023
·
IF 2.3
Jin Xin,Xu Hainan,Hu Qing,Yin Yitong,Qin Meiying,Xia Zhijun
Pelvic organ prolapse (POP) is a common disorder among women that negatively affects women’s quality of life. Early growth response 2 (EGR2) is a transcription factor that regulates cell growth. The present study aimed to explore the role of EGR2 in POP progression and provided a new target for the treatment and prevention of POP. Firstly, we extracted primary vaginal anterior wall fibroblasts from POP tissues and non-POP tissues and then constructed an EGR2-silencing lentivirus for further study. Immunoblotting, qPCR, TUNEL assay, CCK-8 assay, dual luciferase assay, and ELISA assay were carried out. EGR2 expression was much higher in POP tissues than in control tissues, and EGR2 expression positively correlated with cytokine signaling 3 (SOCS3) expression. Knockdown of EGR2 increased cell proliferation, upregulated PCNA expression, and reduced apoptosis in POP fibroblasts. Moreover, we found that the knockdown of EGR2 increased COL1A1 , COL3A1 , and Elastin expression and decreased MMP2 and MMP9 activities, and knockdown of EGR2 increased TGF-β/Smad pathway activity in POP fibroblasts. Interestingly, the results of dual luciferase assay demonstrated that EGR2 was able to increase SOCS3 transcriptional activity. EGR2 knockdown alleviated the apoptosis of POP fibroblasts by reducing SOCS3 expression and improving the proliferation and collagen synthesis of POP fibroblasts. Overall, our study illustrated that EGR2 was highly expressed in POP tissues, and knockdown of EGR2 alleviated apoptosis and reduced matrix degradation in POP fibroblasts. This study might provide a new insight into the pathogenesis of POP.
研究领域:
妇科学
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分子生物学
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细胞生物学
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DOI
PubMed
高影响因子
CHINESE JOURNAL OF CHEMICAL ENGINEERING
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2020
·
IF 2.627
Haiyan Zhou,Yizuo Li,Rui Jiang,Xianlin Wang,Yuanshan Wang,Yaping Xue,Yuguo Zheng
R -2-(4-hydroxyphenoxy)propionic acid ( R -HPPA) is a key intermediate for the synthesis of classic herbicides with high selectivity against grassy weed. The main route for R -HPPA biosynthesis is to hydroxylate the substrate R -2-phenoxypropionic acid ( R -PPA) at C-4 position with microbes. In order to provide sufficient R -PPA for the industrial production of R -HPPA, an effective R -PPA synthesis method was established and optimized in this work. The synthesis process mainly consisted of two steps: (1) synthesis of S -2-chloropropionic acid from L-alanine via diazotization and chlorination reactions; and (2) synthesis of R -PPA from S -2-chloropropionic acid and phenol via etherification reaction. The optimal reaction conditions were as follows: HCl: NaNO 2 : KI: L-Ala = 2.0: 1.2: 0.7: 1.0 (in molar), 125 °C reflux for 1.5 h, with KI as catalyst, and KI: S -2-chloropropionic acid: phenol = 0.075: 1.2: 1.0 (in molar). Under these conditions, an improved molar conversion rate (74.9%, calculated in phenol) was achieved. After extraction using anionic exchange resin Amberlite IRA-400 (CI), R -PPA product with a purity of 95.08% was obtained. The purified R -PPA was identified and evaluated in the application of the biotransformative production of R -HPPA. The results indicated that the synthesized R -PPA supported the R -HPPA biosynthesis with a comparable yield as that of the standard R -PPA. The R -PPA synthesis method provided herein exhibited the advantages of low price and easy availability of raw materials, less toxicity of reagents, simple manipulations, and low equipment/instrument requirements.
研究领域:
生物化学
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有机化学
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工业微生物学
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DOI
高影响因子
Drug Metabolism and Pharmacokinetics
·
2019
·
IF 1.874
Yang Zhang,Chen Su,Jinxiu Lei,Lu Chen,Haihong Hu,Su Zeng,Lushan Yu
Mandelic acid (MA) is generally used as a biomarker of the exposure of styrene , which is classified as a class of hazardous environmental pollutants, and also used as an important chiral intermediate in pharmaceutical industry. The previous studies have found the excretion of phenylglyoxylic acid (PGA) in human and rat, a metabolite of MA, was mainly from S- MA rather than R -MA. The metabolic mechanism, however, is not clear. In order to explore the possible metabolic mechanism, the enzyme types involved in the stereoselectivity metabolism of MA were firstly studied, and then human and rat long-chain 2-hydroxy-acid oxidase 2 (HAO2) were recombinantly expressed to study the metabolic profiles of S- MA and its analogues. The results indicated that HAO2 might catalyze the stereoselectivity metabolism of S- MA in rats. Human HAO2 ( h HAO2) and rat HAO2 ( r HAO2) isozymes β 1 and β 2 were successfully cloned and expressed with high purity and good enzyme activities. The enzyme kinetic profiles of these enzymes were different for S- MA and analogues. The order of catalytic efficiency for h HAO2 and r HAO2, however, was reverse. It might be relevance to the difference in active amino acid residues and loop 4 in human and rat L-2-hydroxy acid oxidase isozyme B crystal structures.
研究领域:
环境科学
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生物化学
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毒理学
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药物化学
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产品关联
DOI
PubMed
高影响因子
JOURNAL OF CHEMICAL AND ENGINEERING DATA
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2014
·
IF 2.045
Libin Chen,Ying Zhang,Sheng Wang,Xiong Zheng,Maogang He
The thermal diffusivities of 2-methoxy-2-methylpropane (MTBE, mass purity, > 0.990, GC) were measured by using the dynamic light scattering method at T = (303.15 to 493.15) K and p = (1.5 to 10) MPa, including saturated liquid, saturated vapor, and compressed liquid. The expanded relative uncertainty in thermal diffusivity was estimated to be less than 2.0 % over the entire investigated range. The polynomial representation for thermal diffusivity of MTBE was proposed by employing the experimental results. Comparing the calculated results with the experimental data, the average absolute deviations are 0.59 % for saturated liquid, 0.38 % for saturated vapor, and 0.43 % for compressed liquid.
研究领域:
化学工程
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物理化学
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产品关联
DOI
高影响因子
MOLECULAR BIOLOGY REPORTS
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2022
·Vol. 49
·期 8
·7665-7676
·
IF 2.742
Jiang Haoran,Wen Xianxin,Zhang Xue,Zhong Xianhua,Li Zhangyong,Zhang Bingyu
Background Hepatocellular carcinoma (HCC) is the main types of primary liver cancer, which shows some abnormal glycosylation, such as the increase of fucose. Lens culinaris agglutinin (LCA), a natural plant lectin that can bind to mannose and fucose, has been reported to be antiproliferative to may tumors. However, the effect of LCA on the vitality and migration ability of human hepatoma cells is not demonstrated. Therefore, the aim of this study is to investigate the effects of LCA on vitality and migration in human hepatoma cells and its potential mechanisms. Methods and results LCA had no significant effect on viability of human hepatoma cells (HCCLM3, MHCC97L and HepG2) and hepatocytes (L02) by CCK-8 kit, but it could inhibit human hepatoma cells migration significantly without affecting hepatocytes by Transwell method. Sugar inhibition assay was used to verify the possible binding site between LCA and human hepatoma cells. The result showed that Mannose- and fucose- related sites were associated with LCA inhibiting human hepatoma cells migration. Moreover, LCA could affect HCCLM3 migration by activating ERK1/2 and JNK1/2/3 signalling pathways. LCA did not affect MMP-2 and MMP-9 of HCCLM3 through gelatinase zymography. However, the results of immunofluorescence standing showed that LCA could reduce the F-actin formation in HCCLM3 via ERK1/2 and JNK1/2/3 signalling pathways. Conclusions LCA might inhibit human hepatoma cell migration by reducing the F-actin formation via the mannose and fucose-mediated ERK1/2 and JNK1/2/3 signalling pathway. This result will deepen people’s understanding on plant lectin as a drug in tumor glycobiology.
研究领域:
肿瘤生物学
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分子生物学
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细胞生物学
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药理学
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产品关联
DOI
PubMed
高影响因子
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
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2018
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IF 2.829
Shaoling Bai,Yaqi Wang,Bin Liu,Yujie Zhu,Ruiwei Guo
Dispersion copolymerization of acrylamide (AM) and sodium 2-acrylamido-2-methylpropanesulfonate (AMPSNa) in aqueous ammonium sulfate (AS) solution was performed without mechanical stirring using a macro-RAFT agent sodium poly(2-acrylamido-2-methylpropanesulfonate) trithiocarbonate (PAMPSNa-TTC) as the stabilizer and 2,2′-azobis(2-methylpropionamide) dihydrochloride as the initiator. The effects of various polymerization parameters were systematically investigated regarding dispersion stability, particle size, molecular weight and apparent viscosity. A new mechanism for particle formation and the particle stability of aqueous dispersion polymerization was proposed.
研究领域:
高分子化学
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材料科学
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产品关联
DOI
高影响因子
EUROPEAN JOURNAL OF LIPID SCIENCE AND TECHNOLOGY
·
2019
·Vol. 121
·期 7
·1900040
·
IF 1.852
Lukai Ma,Guoqin Liu,Xinqi Liu
The formation of three toxic reactive aldehydes, malondialdehyde (MDA), 4-hydroxy-hexenal (HHE), and 4-hydroxy-2-nonenal (HNE), is investigated in five commonly consumed vegetable oils using a method based on the Schaal oven test. HHE is only detected in linseed oil (LO) and rapeseed oil (RO), while MDA and HNE are found to be present in all tested oils. The formation potential of MDA, HHE, and HNE in the tested oils is closely related to the initial polyunsaturated fatty acid (PUFA) content in the oil. Correlation analyses reveal low correlation coefficients for MDA, determining its unsuitability to evaluate the oxidation of oils with low PUFA content, such as palm oil and camellia oil; in contrast, HHE and HNE show sufficient correlations with other oxidation indices in all tested oils. Furthermore, regression analysis indicates that HHE content can predict the oxidation of ω-3 type oil, while HNE content can estimate oxidative deterioration of ω-6 type oils. Particularly, HNE content can also evaluate the oxidation of ω-9 type oils such as PO and CLO with relatively low PUFA level for the high correlations (>0.991, P < 0.01) toward the total oxidation value (TOTOX). Practical Applications : Edible oil consumption continues to increase worldwide. Therefore, it is very important to understand the conditions under which potentially health-damaging compounds are formed in these oils and to develop methods to inhibit their formation or eliminate them from the oils. This study investigates the formation of three toxically reactive aldehydes, namely MDA, HHE, and HNE, through lipid oxidation, specifically PUFA peroxidation. The application of these aldehydes as oxidation indicators for different vegetable oils is also explored. This work could prove beneficial for the quality control of vegetable oils in the edible oil industry. The formation of three toxic aldehydes, MDA, HHE, and HNE in different types of vegetable oils is investigated. Considerable amounts of MDA, HHE, and HNE is found in all the tested oils. The results show the formation of these three aldehydes is competitive. Besides, MDA content is not appropriate to evaluate the oxidation of oils with low PUFA content, such as PO and CLO; while HHE and HNE can characteristically depict the oxidation of ω-3 and ω-6 type oil.
研究领域:
食品科学
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营养学
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产品关联
DOI
高影响因子
ACS Omega
·
2023
·
IF 4.1
Yunfeng Liu,Lang Zhou,Yongfan Tang,Qiang Liu,Wei Li,Yan Zhang
Deep carbonate rock oil and gas reservoir is an important support for increasing oil and gas storage and production at present. The environment of ultradeep and ultrahigh-temperature reservoirs has put forward higher technical requirements for reservoir modification acid technology. Moreover, gelling acid is the main acid solution for high-temperature reservoir acidizing transformation, with a temperature resistance of no more than 180 °C, and the gelling agent is one of the key factors restricting its high-temperature resistance performance. In this paper, AM, AMPS, DMDAAC, and NVP were used as monomers, oxidants, and reducing agents to prepare a high-temperature-resistant polymer gel through polymerization. At the same time, microcapsules were prepared by in situ polymerization using epoxy resin as the wall material. The indoor performance evaluation results indicate that the gelling agent is easily soluble in high-concentration acid solution and has good viscosity increasing effect. At 180 °C and 170 s–1 shear rate, 0.8% mass fraction of the gelling agent was dissolved in 20% mass fraction of hydrochloric acid. After shearing for 60 min, the viscosity remained at about 22.45 mPa·s, demonstrating good temperature resistance and shear resistance, and its performance was superior to existing commonly used gelling agent products.
研究领域:
石油工程
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材料科学
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DOI
PubMed
高影响因子
TOXICON
·
2020
·
IF 2.201
Lingchen Yang,Di Tu,Yingxin Wu,Wei Liu,Yi Hu,Tanbin Liu,Lei Tan,Yalan Li,Hongyu Lei,Yang Zhan,Naidong Wang,Zhibang Deng,Shiyin Guo,Aibing Wang
T-2 and HT-2 widely found in food products can seriously affect human and animal health. In this study, sterilized corn was inoculated with F. poae and incubated to allow fungal growth before being examined via liquid chromatography coupled to tandem mass spectrometry (HPLC-MS/MS) to determine the concentrations of T-2/HT-2. Broilers were then fed with a mix of moldy corn and normal feed at different ratios to obtain different toxin doses. After 35 days, the contaminated feed was replaced with mycotoxin-free feed and the distribution and concentration of residual toxins in the tissues and organs of the chickens were examined at different time points. The results showed that at the time of feed replacement (0 h), T-2 residue was present at significantly higher concentrations in the lungs and small intestines than in other tissues ( P < 0.05). In addition, T-2 concentrations increased in a dose-dependent manner in the tissues of chickens in the low-, medium-, and high-dose groups; however, the differences in concentration between the groups were not statistically significant. The HT-2 content (0 h) in the livers and small intestines was significantly higher than that in other tissues ( P < 0.05). At 48 h post-feed replacement, the concentration of T-2 dropped below detectable levels in all tissues while HT-2 could still be detected at 192 h post-feed replacement. Thus, this study reveals the distribution and persistence of residual T-2/HT-2 from moldy feed in broilers, providing a reference for the detection of these toxins in animal-derived food products and a theoretical basis for formulating food-safety and quality standards.
研究领域:
动物科学
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毒理学
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食品安全
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产品关联
DOI
PubMed
高影响因子
CRYSTENGCOMM
·
2018
·Vol. 20
·期 8
·1151-1157
·
IF 3.304
Qiangwen Fan,Xiaowei Duan,Hong Yan
The solid state [2 + 2] photocycloaddition of N,N′-diacyl-1,4-dihydropyrazines has been investigated using thiourea as a template to preorient the reactants in the crystalline state in a manner that is beneficial for the [2 + 2] photocycloaddition. The structures of the photoadducts, syn-dimers and cage-dimers, were determined using NMR and single-crystal X-ray diffraction. According to the topochemical principles used to assess the feasibility of solid state photochemical [2 + 2] cycloaddition, topological analysis of cocrystals consisting of the N,N′-diacyl-1,4-dihydropyrazines and thiourea, as well as the syn-dimers, was performed to investigate the influence of packing modes and non-covalent interactions on their solid state photoreactivity. The results showed that the solid state [2 + 2] reactivities of both the N,N′-diacyl-1,4-dihydropyrazines assembled using thiourea and the syn-dimers were controlled by the topochemical orientation of the potentially reactive double bonds and the H-bonding interactions within the adjacent reactive molecules.
研究领域:
有机化学
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光化学
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晶体工程
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超分子化学
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药物合成
✓ 已验证
DOI
高影响因子
JOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE
·
2023
·Vol. 103
·期 6
·2824-2837
·
IF 4.1
Yiting Wen,Yujia Zhang,Xiaoli Zhang,Linjun Wang,Qiuxia Pan,Qiuhan Bai,Du Zhu,Weiming Chai
BACKGROUND Tyrosinase is the key enzyme involved in enzymatic browning of plant-derived foods. Inhibition of tyrosinase activity contributes to the control of food browning. Due to safety regulations or other issues, most identified tyrosinase inhibitors are not suitable for practical use. Therefore, it is necessary to search for novel tyrosinase inhibitors. In this study, the anti-tyrosinase activity and mechanism of albendazole and 2-(2-aminophenyl)-1 H -benzimidazole (2-2-A-1HB) were investigated through ultraviolet–visible absorption spectroscopy, fluorescence spectra, molecular docking, and molecular dynamic (MD) simulation. The anti-browning effect of albendazole on fresh-cut apples was then elucidated. RESULTS Albendazole and 2-2-A-1HB were both efficient tyrosinase inhibitors with IC 50 of 51 ± 1.5 and 128 ± 1.3 μmol L −1 , respectively. Albendazole suppressed tyrosinase non-competitively and formed tyrosinase–albendazole complex statically. Hydrogen bond and hydrophobic interaction were major driving forces in stabilizing the tyrosinase–albendazole complex. While 2-2-A-1HB inhibited the enzyme competitively and quenched its intrinsic fluorescence through a static mechanism, it generated strong binding affinity with tyrosinase through hydrophobic interaction. MD simulations further validated that albendazole/2-2-A-1HB could form stable complexes with tyrosinase and loosened its basic framework structure, leading to a change in secondary structure and conformation. In addition, albendazole could delay the browning of fresh-cut apples by inhibiting the activity of polyphenol oxidase, peroxidase and phenylalanine ammonia-lyase, and reducing the oxidation of phenolic compounds. CONCLUSION This research might provide a deep view of tyrosinase inhibition by benzimidazole derivatives and a theoretical basis for developing albendazole as a potential fresh-keeping agent. © 2023 Society of Chemical Industry.
研究领域:
食品科学
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生物化学
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分子生物学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）