A novel ternary complex of Cu(pcpa)2(aben)2 (pcpa=p-chlorophenoxyacetic acid anion,aben=2-amino benzothiazole) was synthesized by the reaction of copper acetate,2-amino benzothiazole and p-chlorophenoxyacetic ac...A novel ternary complex of Cu(pcpa)2(aben)2 (pcpa=p-chlorophenoxyacetic acid anion,aben=2-amino benzothiazole) was synthesized by the reaction of copper acetate,2-amino benzothiazole and p-chlorophenoxyacetic acid.Elemental analysis,IR,UV and X-ray single-crystal diffraction were carried out to determine the composition and crystal structure.The crystal crystalli-zes in the monoclinic system,space group C2/c with a=25.795(4),b=7.384(3),c =17.741(6),β=107.47(2)°,C30H24Cl2CuN4O6S2,Mr=735.09,V=3223.2(18) 3,Z=4,Dc=1.515 Mg/m3,λ(MoKα)=0.71073 ,μ=1.022 mm-1,F(000)=1500,the final R=0.0464 and wR=0.1244.A total of 3218 unique reflections were collected,of which 2228 with I 〉 2σ(I) were observed.The Cu(II) atom is four-coordinated with two carboxylate oxygen atoms of the two pcpa ligands and two nitrogen atoms in thiazole rings of two aben ligands.The analysis of crystal structure shows intermolecular and intramolecular hydrogen bonds between amino-nitrogen atoms of the two aben ligands and carboxylate oxygen atoms of the two pcpa ligands.The antimicrobial properties of the title complex and its two free ligands were tested against representative bacterial and fungal strains.Results show that the antibacterial activity of the complex is less than or equal to that of 2-amino benzothiazole,but for yeasts and moulds,it exhibits excellent inhibitory effect better than that of its two free ligands.展开更多
Water stress is a critical environmental adversity that significantly impacts the growth,development,and yield of flax plants.In this study,flax seeds were cultivated under different water irrigation requirements(WIR)...Water stress is a critical environmental adversity that significantly impacts the growth,development,and yield of flax plants.In this study,flax seeds were cultivated under different water irrigation requirements(WIR)(100%,75%,and 50%)to investigate the effects of exogenously supplied nitric oxide(NO)donor sodium nitroprusside(SNP)as foliar treatments at concentrations of 0.0 mmol/L,0.5 mmol/L,1.0 mmol/L,and 2.0 mmol/L.Drought stress led to a significant decrease in plant growth,photosynthetic pigments,yield components such as oil and total carbohydrate percentage.It also resulted in an increase in leaf H2O2 production,lipid peroxidation levels and activities of enzymatic antioxidants including polyphenol oxidase,superoxide dismutase,and nitrate reductase enzymes.However,foliar application of SNP improved photosynthetic pigments and antioxidant defense system which mitigated the negative impact of water stress on growth and yield productivity by reducing oxidative damage caused by reactive oxygen species accumulation.The use of SNP also decreased H_(2)O_(2) accumulation levels,lipid peroxidation levels,and improved membrane stability.SNP treatment at concentration of 2 mmol/L showed superior results compared to other concentrations with extremely significant increases observed in yield characteristics such as oil content,total carbohydrate percentages,and unsaturated fatty acids to saturated fatty acids ratio.展开更多
This research investigates the mechanical and thermal properties of Morus alba combined with polylactic acid in comparison with other natural fibers. The study uses three different fiber and PLA compositions - 20%, 30...This research investigates the mechanical and thermal properties of Morus alba combined with polylactic acid in comparison with other natural fibers. The study uses three different fiber and PLA compositions - 20%, 30%, and 40% respectively - to produce composite materials. In addition, another composite with the same fiber volume is treated with a 4% NaOH solution to improve mechanical properties. The composites are processed by twin-screw extrusion, granulation, and injection molding. Tensile strength measurements of raw fibers and NaOH-treated fibers were carried out using a single-fiber tensile test with a gauge length of 40 mm. It was observed that the NaOH surface treatment increases the resistance against tensile loading and exhibited improved properties for raw fiber strands. The diameter of the fibers was measured using optical microscopy. During this research, flexural tests, impact tests, differential scanning calorimetry (DSC), and heat deflection temperature measurements (HDT) were conducted to evaluate the mechanical and thermal properties of the developed composite samples. The results indicate that the mechanical properties of NaOH-treated Morus alba-reinforced polylactic acid outperform both virgin PLA samples and untreated Morus alba samples.展开更多
BACKGROUND: It has been reported that high-dose salicylates improve free fatty acids (FFAs)-induced insulin resistance and beta-cell dysfunction in vitro, but the mechanism remains uncertain. In insulin-resistant rats...BACKGROUND: It has been reported that high-dose salicylates improve free fatty acids (FFAs)-induced insulin resistance and beta-cell dysfunction in vitro, but the mechanism remains uncertain. In insulin-resistant rats, we found that the supplementation of sodium salicylate is associated with a reduction of plasma malondialdehyde (MDA), a marker of oxidative stress. Few studies have investigated the effects of salicylates on oxidative stress levels in insulin-resistant animal models. This study aimed to assess the effect of sodium salicylate on insulin sensitivity and to explore the potential mechanism by which it improves hepatic and peripheral insulin resistance. METHODS: Intralipid+heparin (IH), saline (SAL), or intralipid+heparin+sodium salicylate (IHS) were separately infused for 7 hours in normal Wistar rats. During the last 2 hours of the infusion, hyperinsulinemic-euglycemic clamping was 3 performed with [6-(3)H] glucose tracer. Plasma glucose was measured using the glucose oxygenase method. Plasma insulin and C-peptide were determined by radioimmunoassay. MDA levels and glutathione peroxidase (GSH-PX) activity in the liver and skeletal muscle were measured with colorimetric kits. RESULTS: Compared with infusion of SAL, IH infusion increased hepatic glucose production (HGP), and decreased glucose utilization (GU) (P<0.05). The elevation of plasma free fatty acids increased the MDA levels and decreased the GSH-PX activity in the liver and muscle (P<0.01). Sodium salicylate treatment decreased HGP, elevated GU (P<0.05), reduced MDA content by 60% (P<0.01), and increased the GSH-PX activity by 35% (P<0.05). CONCLUSIONS: Short-term elevation of fatty acids induces insulin resistance by enhancing oxidative stress levels in the liver and muscle. The administration of the anti-inflammatory drug sodium salicylate reduces the degree of oxidative stress, therefore improving hepatic and peripheral insulin resistance. IKK-beta and NF-kappa B provide potential pathogenic links to oxidative stress.展开更多
The efficient, green, facile, mild and straightforward conversion procedure for the oxidation of cyclic ketones to lactones at room temperature utilizing potassium peroxydisulfate (K2S2O8) in acidic media is satisfa...The efficient, green, facile, mild and straightforward conversion procedure for the oxidation of cyclic ketones to lactones at room temperature utilizing potassium peroxydisulfate (K2S2O8) in acidic media is satisfactory to high yields without using traditional chlorinated solvents is reported. This oxidative reagent is cheap and friendly environmental procedure for industrial purposes than use of organic peracids.展开更多
Objective To explore the effects and mechanisms of ascorbic acid (AA) and sodium selenite (SS) on growth inhibition and redifferentiation in human gastric cancer cells. Methods In the present study, trypan blue dye...Objective To explore the effects and mechanisms of ascorbic acid (AA) and sodium selenite (SS) on growth inhibition and redifferentiation in human gastric cancer cells. Methods In the present study, trypan blue dye exclusion method was used to determine the cell growth curve and mitotic index, cell electrophoresis and colonogenic potential were used as the indexes of redifferentiation. In order to find out the mechanisms of redifferentiation, the activities of superoxide dismutase (SOD), glutathione peroxidase (GPX) and catalase (CAT) were assayed, the content of malondialdehyde (MDA), reduced glutathione (GSH) and H2O2 were evaluated. Results After treatment with AA 3 mol/L + SS 2μmol/L, the growth rate and mitotic index of human gastric cancer cells (MGc-803) decreased remarkably. The indexes related with cell malignancy were alleviated. For example, cell surface charge was obviously decreased, the electrophoresis rate was dropped from 2.21 to 1.15μm·s-1·V-1·cm-1. The indexes related with cell redifferentiation were promoted. For example, the colonogenic potential was decreased to 93.5%. These results indicated that redifferentiation of human gastric cancer cells was successfully induced by AA + SS. The activities of SOD and GPX were significantly higher, while the activity of CAT was slower in treated group than that in the control. The content of MDA was slightly decreased, GSH was sharply decreased, and H2O2 content was dramatically increased. Conclusion These results indicated that combination of ascorbic acid and sodium selenite may induce the redifferentiation of human gastric cancer cells and inhibit cell growth by virtue of enhancing the activities of antioxidative enzymes and inducing the formation of H2O2, and altering the cell redox status. Combination of ascorbic acid and sodium selenite may be a potent anticancer agent for human gastric cancer.展开更多
This study was conducted to comprehensively evaluate the effects of salicylic acid and sodium molybdate on cold tolerance of an ornamental plant Bougainvillea glabra and to provide a theoretical guidance for landscape...This study was conducted to comprehensively evaluate the effects of salicylic acid and sodium molybdate on cold tolerance of an ornamental plant Bougainvillea glabra and to provide a theoretical guidance for landscape maintenance.B.glabra plants were treated with 0.5 mmol/L salicylic acid and 2.0 μmol/L alone or in combination,and then exposed to low temperature stress before physiological indices were measured.The results showed that all salicylic acid and sodium molybdate treatments reduced the relative conductivity and malondialdehyde( MDA) content of B.glabra to varying extents under the stress of low temperature,and more significant effect was achieved by using the two agents in combination.Oxygen free radicals production rate increased with decreasing temperature from 20 to 6 ℃,but declined with temperature decreasing from 3 to-3 ℃.The SOD activity of the control( CK) was significantly lower than that of other treatments at 0 and-3 ℃.The treatments with salicylic acid and sodium molybdate alone and in combination increased POD activity of B.glabra plants,especially at 0 ℃,as the POD activity of treatments T1,T2 and T3 was significantly higher than that of CK at 0 ℃.In addition,under low temperature stress,the contents of soluble sugar,starch and proline increased initially and decreased subsequently with temperature decreasing.The soluble sugar content at 3 ℃,starch and proline contents at 0 and-3 ℃ in treatments with salicylic acid and sodium molybdate alone and in combination were significantly higher than those of CK.All above results proved that salicylic acid and sodium molybdate are able to improve cold tolerance of B.glabra,and better effect can be achieved by using them together.展开更多
The pretreatment for the removal of small molecules from poly(acrylic acid) sodium (PAAS) solution by continuous diafiltration was investigated using ultrafiltration membrane. The effects of PAAS concentration, pH, tr...The pretreatment for the removal of small molecules from poly(acrylic acid) sodium (PAAS) solution by continuous diafiltration was investigated using ultrafiltration membrane. The effects of PAAS concentration, pH, trans-membrane pressure and pretreatment time on the permeate concentration and permeate flux were studied. The results show that the necessary pretreatment time (NPT) increases with PAAS concentration, decreases with TMP. The change trend of permeate flux with time is affected by pH. The permeate fluxes rapidly decrease from the start, and then increase gradually to stable values at pH 5.0, pH 7.0 and pH 9.3. However, it decreases gradually with time till a state value at pH 3.0 (iso-electric point, IEP). The removal of small molecules is easy at pH greater than iso-electric point (IEP). The change of filtration potential with time indicates the similar trend to that of permeation concentration, but the former is more convenient for indication of NPT.展开更多
AIM:To compare the potential protective effects of epigallocatechin gallate(EGCG) and ellagic acid(EA) in an experimental cataract model.●METHODS:Twenty-eight Spraque-Dawley rat pups were assigned into four gro...AIM:To compare the potential protective effects of epigallocatechin gallate(EGCG) and ellagic acid(EA) in an experimental cataract model.●METHODS:Twenty-eight Spraque-Dawley rat pups were assigned into four groups.All the rats,except for those in the control group,were injected subcutaneously sodium selenite to induce experimental cataract on the postpartum ninth day,and between 10 th and 14 th days.Rats in the sham,EGCG,and EA groups were intraperitoneally administered 50 mg/(kg·d) saline solution,50 mg/(kg·d) EGCG and 200 mg/(kg·d) EA,respectively.The reduced glutathione(GSH) and malondialdehyde(MDA) levels,total antioxidant status(TAS) and total oxidant status(TOS) in lens supernatants were measured.RESULTS:The mean cataract gradings in EGCG and EA groups were found to be significantly lower than that in sham group(P〈0.001).The mean GSH levels and TASs in EGCG and EA groups were significantly higher than that in sham group while mean MDA levels and TOSs in EGCG and EA groups were significantly lower than that in the sham group(P〈0.001).CONCLUSION:EGCG and EA have protective effects on cataract development via the inhibition of oxidative stress.展开更多
A new one-dimensional double chain coordination polymer, [Na(cbsH)(H2O)3]n (cbsH = 4-carboxy-benzenesulfonic anion), has been synthesized by aqueous reaction, structurally described, and thermally characterized....A new one-dimensional double chain coordination polymer, [Na(cbsH)(H2O)3]n (cbsH = 4-carboxy-benzenesulfonic anion), has been synthesized by aqueous reaction, structurally described, and thermally characterized. It crystallizes in the triclinic system, space group P with a = 5.645(4), b = 7.905(5), c = 13.043(8) , α = 89.391(7), β = 80.637(7), γ = 82.845(7)°, V = 569.8(6) 3, Z = 2, C7H11NaO8S, Mr = 278.21, Dc = 1.622 Kg/m3, F(000) = 288, R = 0.0260 and wR = 0.0697. The title compound consists of one-dimensional double chains. 4-Carboxy-benzenesulfonic acid acts as a bridging bidentate ligand to link two sodium(I) ions to form a binuclear structure. Remarkably, the sodium(I) ion behaves as a metal bridge so that the binuclear structure units are connected to construct a one-dimensional double chain polymer. Furthermore, a 3-D framework is assembled through intermolecular hydrogen bonds. Thermogravimetric analysis shows that this compound begins losing the free solvent molecules at 106 ℃ and decompounding completely at 580 ℃.展开更多
The effects of matrix silicate and experimental conditions on the determination of iron in flame atomic absorption spectrometry (FAAS) were investigated. It was found that boric acid as a matrix modifier obviously e...The effects of matrix silicate and experimental conditions on the determination of iron in flame atomic absorption spectrometry (FAAS) were investigated. It was found that boric acid as a matrix modifier obviously eliminated silicate interference. Under the optimum operating conditions, the determination results of iron in layered crystal sodium disilicate and sodium silicate samples by FAAS were satisfactory. The linear range of calibration curve is 0-10.5 μg.mL^-1, the relative standard deviation of method is 1.2%-2.2%, the recovery of added iron is 96.0%- 101%, the sensitivity is 0.19 μg.mL^-l and the detection limit is 77 ng.mL^-1. The effect of the determination of iron of the standard curve method, standard addition calibration and colorimetry method was the same, but the first has the merits of rapid sample preparation, reduced contamination risks and fast analysis.展开更多
Synthesis of 2-aryl-1-arylmethyl-1H-1,3-benzo[d]imidazoles by the reaction of o-phenylenediamine with substituted aromatic aldehydes in the presence of 1-heptanesulfonic acid sodium salt (10 mol%) at room temperatur...Synthesis of 2-aryl-1-arylmethyl-1H-1,3-benzo[d]imidazoles by the reaction of o-phenylenediamine with substituted aromatic aldehydes in the presence of 1-heptanesulfonic acid sodium salt (10 mol%) at room temperature. The reactions were performed in acetonitrile:water (8:2). The method was proved to be eco-friendly, convenient and the products were isolated with good yields (82- 90%).展开更多
Background:Identifying regulatory measures to promote glucose oxidative metabolism while simultaneously reducing amino acid oxidative metabolism is one of the foremost challenges in formulating low-protein(LP)diets de...Background:Identifying regulatory measures to promote glucose oxidative metabolism while simultaneously reducing amino acid oxidative metabolism is one of the foremost challenges in formulating low-protein(LP)diets designed to reduce the excretion of nitrogen-containing substances known to be potential pollutants.In this study,we investigated the effects of adding sodium dichloroacetate(DCA)to a LP diet on nitrogen balance and amino acid metabolism in the portal-drained viscera(PDV)and liver of pigs.To measure nitrogen balance,18 barrows(40±1.0 kg)were fed one of three diets(n=6 per group):18%crude protein(CP,control),13.5%CP(LP),and 13.5%CP+100 mg DCA/kg dry matter(LP-DCA).To measure amino acid metabolism in the PDV and liver,15 barrows(40±1.0 kg)were randomly assigned to one of the three diets(n=5 per group).Four essential amino acids(Lys,Met,Thr,and Trp)were added to the LP diets such that these had amino acid levels comparable to those of the control diet.Results:The LP-DCA diet reduced nitrogen excretion in pigs relative to that of pigs fed the control diet(P<0.05),without any negative effects on nitrogen retention(P>0.05).There were no differences between the control and LP-DCA groups with respect to amino acid supply to the liver and extra-hepatic tissues in pigs(P>0.05).The net release of ammonia into the portal vein and production rate of urea in the liver of pigs fed the LP-DCA diet was reduced relative to that of pigs fed the control and LP diets(P<0.05).Conclusion:The results indicated that addition of DCA to a LP diet can efficiently reduce nitrogen excretion in pigs and maximize the supply of amino acids to the liver and extra-hepatic tissues.展开更多
To investigate the therapeutic effect of nigh-dosage γ-aminobutyric acid (GABA) on acute tetramine (TET) poisoning, 50 Kunming mice were divided into 5 groups at random and the antidotal effects of GABA or sodium...To investigate the therapeutic effect of nigh-dosage γ-aminobutyric acid (GABA) on acute tetramine (TET) poisoning, 50 Kunming mice were divided into 5 groups at random and the antidotal effects of GABA or sodium dimercaptopropane sulfonate (Na-DMPS) on poisoned mice in different groups were observed in order to compare the therapeutic effects of nigh-dosage GABA with those of Na-DMPS. Slices of brain tissue of the poisoned mice were made to examine pathological changes of cells. The survival analysis was employed. Our results showed that both high-dosage GABA and Na-DMPS could obviously prolong the survival time, delay onset of convulsion and muscular twitch, and ameliorate the symptoms after acute tetramine poisoning in the mice. Better effects could be achieved with earlier use of high dosage GABA or Na-DMPS. There was no significant difference in prolonging the survival time between high-dose GABA and Na-DMPS used immediately after poisioning. It is concluded that high-dosage GABA can effectively antagonize acute toxicity of terarnine in mice. And it is suggested that nigh-dosage GABA may be used as an excellent antidote for acute TET poisoning in clinical practice. The indications and correct dosage for clinical use awaits to be further studied.展开更多
Wolframite notation with benzyl arsonic acid and sodium butyl xanthate is studied,at first.It shows the efficiency of mineral processig is good when the two agents are added together.Then the synergism of sodium butyl...Wolframite notation with benzyl arsonic acid and sodium butyl xanthate is studied,at first.It shows the efficiency of mineral processig is good when the two agents are added together.Then the synergism of sodium butyl xanthate and benzyl arsonic acid is studied also by HPLC.展开更多
We reported an inexpensive and high-efficiency hydrogen generation method from NaBH4 hydrolysis promoted by oxalic acid.NaBH4 and H2C2O4 were premixed and hydrogen generation was initiated by adding water into the sol...We reported an inexpensive and high-efficiency hydrogen generation method from NaBH4 hydrolysis promoted by oxalic acid.NaBH4 and H2C2O4 were premixed and hydrogen generation was initiated by adding water into the solid mixture.H2C2O4 was selected as the acid promotor due to its solid state and low mass per proton.The effect of reactant ratio on the hydrogen yield and hydrogen storage density was investigated.With optimized reactant ratio,high gravimetric hydrogen storage up to 4.4wt%based on all the reactants can be achieved with excellent hydrogen generation kinetics.展开更多
There were several techniques determined for the analysis of citrate and citric acid mixtures in the pharmaceutical dosage forms. Titration methods, photometric and ion chromatographic methods were used for their dete...There were several techniques determined for the analysis of citrate and citric acid mixtures in the pharmaceutical dosage forms. Titration methods, photometric and ion chromatographic methods were used for their determination. These methods will restrict too many factors where the accurate quantification of citrate and citric acid is extremely challenging. Citric acid is the natural flavor used as a preservative for many pharmaceutical applications. Deformulation techniques used for the manufacturing of generic drugs require authentic data for their regulatory submissions. Simple accurate and reproducible validated method developed for the determination of citric acid and sodium citrate by titration followed by HPLC analysis. Free citric acid was determined by the titration method and total citric acid was determined by HPLC analysis. After subtracting the free citric acid from total citric acid content, citric acid present in the sodium citrate content was determined. Sodium citrate content was determined by applying sodium correction factor to the subtracted value of the citric acid. The results met all the validation parameters and the method was successfully measured the amount of citric acid and sodium citrate in the marketed ophthalmic/oral solutions.展开更多
This paper reports the ultrastructural changes of trichomonas vaginaiis (T. vag. ) under the action of s-(-)usnic acid sodium in vitro. These changes can be shown by the following results:At first, the degranulation o...This paper reports the ultrastructural changes of trichomonas vaginaiis (T. vag. ) under the action of s-(-)usnic acid sodium in vitro. These changes can be shown by the following results:At first, the degranulation of the rough endoplasmic reticulum (RER) took place, the polyribosomes disaggregated. And then, the Golgi complex and the endoplasmic reticulum dilated. The cytoplasmic matrix presented and inhomogeneous apperance. Finally, the biomembrane loosed and fractured.The cell nuclei presented the karyorrhexis.展开更多
BACKGROUND Bowel preparation in children can be challenging.AIM To describe the efficacy, safety, and tolerability of sodium picosulfate, magnesium oxide, and citric acid(SPMC) bowel preparation in children.METHODS Ph...BACKGROUND Bowel preparation in children can be challenging.AIM To describe the efficacy, safety, and tolerability of sodium picosulfate, magnesium oxide, and citric acid(SPMC) bowel preparation in children.METHODS Phase 3, randomized, assessor-blinded, multicenter study of low-volume, divided dose SPMC enrolled children 9-16 years undergoing elective colonoscopy. Participants 9-12 years were randomized 1:1:1 to SPMC ? dose × 2, SPMC 1 dose × 2, or polyethylene glycol(PEG). Participants 13-16 years were randomized 1:1 to SPMC 1 dose × 2 or PEG. PEG-based bowel preparations were administered per local protocol. Primary efficacy endpoint for quality of bowel preparation was responders(rating of ‘excellent' or ‘good') by modified Aronchick Scale. Secondary efficacy endpoint was participant's tolerability and satisfaction from a 7-item questionnaire. Safety assessments included adverse events(AEs) and laboratory evaluations.RESULTS 78 participants were randomized, 48 were 9-12 years, 30 were 13-16 years. For the primary efficacy endpoint in 9-12 years, 50.0%, 87.5%, and 81.3% were responders for SPMC ? dose × 2, SPMC 1 dose × 2, and PEG groups, respectively. Responder rates for 13-16 years were 81.3% for SPMC 1 dose × 2 and 85.7% for PEG. Overall, 43.8% of participants receiving SPMC 1 dose × 2 reported it was ‘very easy' or ‘easy' to drink, compared with 20.0% receiving PEG. Treatment-emergent AEs were reported by 45.5% of participants receiving SPMC 1 dose × 2 and 63.0% receiving PEG.CONCLUSION SPMC was an efficacious and safe for bowel preparation in children 9-16 years, with comparable efficacy to PEG. Tolerability for SPMC was higher compared to PEG.展开更多
As a mono-sodium salt form of alendronic acid,alendronate sodium presents multi-level ionization for the dissociation of its four hydroxyl groups.The dissociation constants of alendronate sodium were determined in thi...As a mono-sodium salt form of alendronic acid,alendronate sodium presents multi-level ionization for the dissociation of its four hydroxyl groups.The dissociation constants of alendronate sodium were determined in this work by studying the piecewise linear relationship between volume of titrant and p H value based on acidbase potentiometric titration reaction.The distribution curves of alendronate sodium were drawn according to the determined p Ka values.There were 4 dissociation constants(pKa_1=2.43,pKa_2=7.55,pKa_3=10.80,pKa_4=11.99,respectively) of alendronate sodium,and 12 existing forms,of which 4 could be ignored,existing in different p H environments.展开更多
基金Supported by the International Scientific and Technical Cooperation Program of the Ministry of Science and Technology of China (2009DFA42850)
文摘A novel ternary complex of Cu(pcpa)2(aben)2 (pcpa=p-chlorophenoxyacetic acid anion,aben=2-amino benzothiazole) was synthesized by the reaction of copper acetate,2-amino benzothiazole and p-chlorophenoxyacetic acid.Elemental analysis,IR,UV and X-ray single-crystal diffraction were carried out to determine the composition and crystal structure.The crystal crystalli-zes in the monoclinic system,space group C2/c with a=25.795(4),b=7.384(3),c =17.741(6),β=107.47(2)°,C30H24Cl2CuN4O6S2,Mr=735.09,V=3223.2(18) 3,Z=4,Dc=1.515 Mg/m3,λ(MoKα)=0.71073 ,μ=1.022 mm-1,F(000)=1500,the final R=0.0464 and wR=0.1244.A total of 3218 unique reflections were collected,of which 2228 with I 〉 2σ(I) were observed.The Cu(II) atom is four-coordinated with two carboxylate oxygen atoms of the two pcpa ligands and two nitrogen atoms in thiazole rings of two aben ligands.The analysis of crystal structure shows intermolecular and intramolecular hydrogen bonds between amino-nitrogen atoms of the two aben ligands and carboxylate oxygen atoms of the two pcpa ligands.The antimicrobial properties of the title complex and its two free ligands were tested against representative bacterial and fungal strains.Results show that the antibacterial activity of the complex is less than or equal to that of 2-amino benzothiazole,but for yeasts and moulds,it exhibits excellent inhibitory effect better than that of its two free ligands.
文摘Water stress is a critical environmental adversity that significantly impacts the growth,development,and yield of flax plants.In this study,flax seeds were cultivated under different water irrigation requirements(WIR)(100%,75%,and 50%)to investigate the effects of exogenously supplied nitric oxide(NO)donor sodium nitroprusside(SNP)as foliar treatments at concentrations of 0.0 mmol/L,0.5 mmol/L,1.0 mmol/L,and 2.0 mmol/L.Drought stress led to a significant decrease in plant growth,photosynthetic pigments,yield components such as oil and total carbohydrate percentage.It also resulted in an increase in leaf H2O2 production,lipid peroxidation levels and activities of enzymatic antioxidants including polyphenol oxidase,superoxide dismutase,and nitrate reductase enzymes.However,foliar application of SNP improved photosynthetic pigments and antioxidant defense system which mitigated the negative impact of water stress on growth and yield productivity by reducing oxidative damage caused by reactive oxygen species accumulation.The use of SNP also decreased H_(2)O_(2) accumulation levels,lipid peroxidation levels,and improved membrane stability.SNP treatment at concentration of 2 mmol/L showed superior results compared to other concentrations with extremely significant increases observed in yield characteristics such as oil content,total carbohydrate percentages,and unsaturated fatty acids to saturated fatty acids ratio.
文摘This research investigates the mechanical and thermal properties of Morus alba combined with polylactic acid in comparison with other natural fibers. The study uses three different fiber and PLA compositions - 20%, 30%, and 40% respectively - to produce composite materials. In addition, another composite with the same fiber volume is treated with a 4% NaOH solution to improve mechanical properties. The composites are processed by twin-screw extrusion, granulation, and injection molding. Tensile strength measurements of raw fibers and NaOH-treated fibers were carried out using a single-fiber tensile test with a gauge length of 40 mm. It was observed that the NaOH surface treatment increases the resistance against tensile loading and exhibited improved properties for raw fiber strands. The diameter of the fibers was measured using optical microscopy. During this research, flexural tests, impact tests, differential scanning calorimetry (DSC), and heat deflection temperature measurements (HDT) were conducted to evaluate the mechanical and thermal properties of the developed composite samples. The results indicate that the mechanical properties of NaOH-treated Morus alba-reinforced polylactic acid outperform both virgin PLA samples and untreated Morus alba samples.
基金supported by a grant from the Bureau of Education of Liaoning Province,China (No.20060999)
文摘BACKGROUND: It has been reported that high-dose salicylates improve free fatty acids (FFAs)-induced insulin resistance and beta-cell dysfunction in vitro, but the mechanism remains uncertain. In insulin-resistant rats, we found that the supplementation of sodium salicylate is associated with a reduction of plasma malondialdehyde (MDA), a marker of oxidative stress. Few studies have investigated the effects of salicylates on oxidative stress levels in insulin-resistant animal models. This study aimed to assess the effect of sodium salicylate on insulin sensitivity and to explore the potential mechanism by which it improves hepatic and peripheral insulin resistance. METHODS: Intralipid+heparin (IH), saline (SAL), or intralipid+heparin+sodium salicylate (IHS) were separately infused for 7 hours in normal Wistar rats. During the last 2 hours of the infusion, hyperinsulinemic-euglycemic clamping was 3 performed with [6-(3)H] glucose tracer. Plasma glucose was measured using the glucose oxygenase method. Plasma insulin and C-peptide were determined by radioimmunoassay. MDA levels and glutathione peroxidase (GSH-PX) activity in the liver and skeletal muscle were measured with colorimetric kits. RESULTS: Compared with infusion of SAL, IH infusion increased hepatic glucose production (HGP), and decreased glucose utilization (GU) (P<0.05). The elevation of plasma free fatty acids increased the MDA levels and decreased the GSH-PX activity in the liver and muscle (P<0.01). Sodium salicylate treatment decreased HGP, elevated GU (P<0.05), reduced MDA content by 60% (P<0.01), and increased the GSH-PX activity by 35% (P<0.05). CONCLUSIONS: Short-term elevation of fatty acids induces insulin resistance by enhancing oxidative stress levels in the liver and muscle. The administration of the anti-inflammatory drug sodium salicylate reduces the degree of oxidative stress, therefore improving hepatic and peripheral insulin resistance. IKK-beta and NF-kappa B provide potential pathogenic links to oxidative stress.
基金support and purchase of Hewlett-Packard 6890 GC-Hewlett-Packard 5973N MSD instrument.
文摘The efficient, green, facile, mild and straightforward conversion procedure for the oxidation of cyclic ketones to lactones at room temperature utilizing potassium peroxydisulfate (K2S2O8) in acidic media is satisfactory to high yields without using traditional chlorinated solvents is reported. This oxidative reagent is cheap and friendly environmental procedure for industrial purposes than use of organic peracids.
文摘Objective To explore the effects and mechanisms of ascorbic acid (AA) and sodium selenite (SS) on growth inhibition and redifferentiation in human gastric cancer cells. Methods In the present study, trypan blue dye exclusion method was used to determine the cell growth curve and mitotic index, cell electrophoresis and colonogenic potential were used as the indexes of redifferentiation. In order to find out the mechanisms of redifferentiation, the activities of superoxide dismutase (SOD), glutathione peroxidase (GPX) and catalase (CAT) were assayed, the content of malondialdehyde (MDA), reduced glutathione (GSH) and H2O2 were evaluated. Results After treatment with AA 3 mol/L + SS 2μmol/L, the growth rate and mitotic index of human gastric cancer cells (MGc-803) decreased remarkably. The indexes related with cell malignancy were alleviated. For example, cell surface charge was obviously decreased, the electrophoresis rate was dropped from 2.21 to 1.15μm·s-1·V-1·cm-1. The indexes related with cell redifferentiation were promoted. For example, the colonogenic potential was decreased to 93.5%. These results indicated that redifferentiation of human gastric cancer cells was successfully induced by AA + SS. The activities of SOD and GPX were significantly higher, while the activity of CAT was slower in treated group than that in the control. The content of MDA was slightly decreased, GSH was sharply decreased, and H2O2 content was dramatically increased. Conclusion These results indicated that combination of ascorbic acid and sodium selenite may induce the redifferentiation of human gastric cancer cells and inhibit cell growth by virtue of enhancing the activities of antioxidative enzymes and inducing the formation of H2O2, and altering the cell redox status. Combination of ascorbic acid and sodium selenite may be a potent anticancer agent for human gastric cancer.
基金Supported by Applied Basic Research Project of Yunnan Province(2017FD087)National Natural Science Foundation of China(31660559)
文摘This study was conducted to comprehensively evaluate the effects of salicylic acid and sodium molybdate on cold tolerance of an ornamental plant Bougainvillea glabra and to provide a theoretical guidance for landscape maintenance.B.glabra plants were treated with 0.5 mmol/L salicylic acid and 2.0 μmol/L alone or in combination,and then exposed to low temperature stress before physiological indices were measured.The results showed that all salicylic acid and sodium molybdate treatments reduced the relative conductivity and malondialdehyde( MDA) content of B.glabra to varying extents under the stress of low temperature,and more significant effect was achieved by using the two agents in combination.Oxygen free radicals production rate increased with decreasing temperature from 20 to 6 ℃,but declined with temperature decreasing from 3 to-3 ℃.The SOD activity of the control( CK) was significantly lower than that of other treatments at 0 and-3 ℃.The treatments with salicylic acid and sodium molybdate alone and in combination increased POD activity of B.glabra plants,especially at 0 ℃,as the POD activity of treatments T1,T2 and T3 was significantly higher than that of CK at 0 ℃.In addition,under low temperature stress,the contents of soluble sugar,starch and proline increased initially and decreased subsequently with temperature decreasing.The soluble sugar content at 3 ℃,starch and proline contents at 0 and-3 ℃ in treatments with salicylic acid and sodium molybdate alone and in combination were significantly higher than those of CK.All above results proved that salicylic acid and sodium molybdate are able to improve cold tolerance of B.glabra,and better effect can be achieved by using them together.
基金Projects(21176264,21476265)supported by the National Natural Science Foundation of China
文摘The pretreatment for the removal of small molecules from poly(acrylic acid) sodium (PAAS) solution by continuous diafiltration was investigated using ultrafiltration membrane. The effects of PAAS concentration, pH, trans-membrane pressure and pretreatment time on the permeate concentration and permeate flux were studied. The results show that the necessary pretreatment time (NPT) increases with PAAS concentration, decreases with TMP. The change trend of permeate flux with time is affected by pH. The permeate fluxes rapidly decrease from the start, and then increase gradually to stable values at pH 5.0, pH 7.0 and pH 9.3. However, it decreases gradually with time till a state value at pH 3.0 (iso-electric point, IEP). The removal of small molecules is easy at pH greater than iso-electric point (IEP). The change of filtration potential with time indicates the similar trend to that of permeation concentration, but the former is more convenient for indication of NPT.
基金Funded by an unrestricted grant from Firat University Scientific Research Unit
文摘AIM:To compare the potential protective effects of epigallocatechin gallate(EGCG) and ellagic acid(EA) in an experimental cataract model.●METHODS:Twenty-eight Spraque-Dawley rat pups were assigned into four groups.All the rats,except for those in the control group,were injected subcutaneously sodium selenite to induce experimental cataract on the postpartum ninth day,and between 10 th and 14 th days.Rats in the sham,EGCG,and EA groups were intraperitoneally administered 50 mg/(kg·d) saline solution,50 mg/(kg·d) EGCG and 200 mg/(kg·d) EA,respectively.The reduced glutathione(GSH) and malondialdehyde(MDA) levels,total antioxidant status(TAS) and total oxidant status(TOS) in lens supernatants were measured.RESULTS:The mean cataract gradings in EGCG and EA groups were found to be significantly lower than that in sham group(P〈0.001).The mean GSH levels and TASs in EGCG and EA groups were significantly higher than that in sham group while mean MDA levels and TOSs in EGCG and EA groups were significantly lower than that in the sham group(P〈0.001).CONCLUSION:EGCG and EA have protective effects on cataract development via the inhibition of oxidative stress.
基金supported by Henan tackle key problem of science and technology (No. 072102270034)
文摘A new one-dimensional double chain coordination polymer, [Na(cbsH)(H2O)3]n (cbsH = 4-carboxy-benzenesulfonic anion), has been synthesized by aqueous reaction, structurally described, and thermally characterized. It crystallizes in the triclinic system, space group P with a = 5.645(4), b = 7.905(5), c = 13.043(8) , α = 89.391(7), β = 80.637(7), γ = 82.845(7)°, V = 569.8(6) 3, Z = 2, C7H11NaO8S, Mr = 278.21, Dc = 1.622 Kg/m3, F(000) = 288, R = 0.0260 and wR = 0.0697. The title compound consists of one-dimensional double chains. 4-Carboxy-benzenesulfonic acid acts as a bridging bidentate ligand to link two sodium(I) ions to form a binuclear structure. Remarkably, the sodium(I) ion behaves as a metal bridge so that the binuclear structure units are connected to construct a one-dimensional double chain polymer. Furthermore, a 3-D framework is assembled through intermolecular hydrogen bonds. Thermogravimetric analysis shows that this compound begins losing the free solvent molecules at 106 ℃ and decompounding completely at 580 ℃.
文摘The effects of matrix silicate and experimental conditions on the determination of iron in flame atomic absorption spectrometry (FAAS) were investigated. It was found that boric acid as a matrix modifier obviously eliminated silicate interference. Under the optimum operating conditions, the determination results of iron in layered crystal sodium disilicate and sodium silicate samples by FAAS were satisfactory. The linear range of calibration curve is 0-10.5 μg.mL^-1, the relative standard deviation of method is 1.2%-2.2%, the recovery of added iron is 96.0%- 101%, the sensitivity is 0.19 μg.mL^-l and the detection limit is 77 ng.mL^-1. The effect of the determination of iron of the standard curve method, standard addition calibration and colorimetry method was the same, but the first has the merits of rapid sample preparation, reduced contamination risks and fast analysis.
文摘Synthesis of 2-aryl-1-arylmethyl-1H-1,3-benzo[d]imidazoles by the reaction of o-phenylenediamine with substituted aromatic aldehydes in the presence of 1-heptanesulfonic acid sodium salt (10 mol%) at room temperature. The reactions were performed in acetonitrile:water (8:2). The method was proved to be eco-friendly, convenient and the products were isolated with good yields (82- 90%).
基金This study was funded by grants from the National Natural Science Foundation of China(31872370,31670123)the Fundamental Research Funds for the Central Universities(XDJK2019B014,XDJK2013C097)the Natural Science Foundation Project of CQ CSTC(cstc2018jcyjAX0025).
文摘Background:Identifying regulatory measures to promote glucose oxidative metabolism while simultaneously reducing amino acid oxidative metabolism is one of the foremost challenges in formulating low-protein(LP)diets designed to reduce the excretion of nitrogen-containing substances known to be potential pollutants.In this study,we investigated the effects of adding sodium dichloroacetate(DCA)to a LP diet on nitrogen balance and amino acid metabolism in the portal-drained viscera(PDV)and liver of pigs.To measure nitrogen balance,18 barrows(40±1.0 kg)were fed one of three diets(n=6 per group):18%crude protein(CP,control),13.5%CP(LP),and 13.5%CP+100 mg DCA/kg dry matter(LP-DCA).To measure amino acid metabolism in the PDV and liver,15 barrows(40±1.0 kg)were randomly assigned to one of the three diets(n=5 per group).Four essential amino acids(Lys,Met,Thr,and Trp)were added to the LP diets such that these had amino acid levels comparable to those of the control diet.Results:The LP-DCA diet reduced nitrogen excretion in pigs relative to that of pigs fed the control diet(P<0.05),without any negative effects on nitrogen retention(P>0.05).There were no differences between the control and LP-DCA groups with respect to amino acid supply to the liver and extra-hepatic tissues in pigs(P>0.05).The net release of ammonia into the portal vein and production rate of urea in the liver of pigs fed the LP-DCA diet was reduced relative to that of pigs fed the control and LP diets(P<0.05).Conclusion:The results indicated that addition of DCA to a LP diet can efficiently reduce nitrogen excretion in pigs and maximize the supply of amino acids to the liver and extra-hepatic tissues.
基金This project was supported by a grant from Research and Development Program of Science and Technology of Hubei Province (No 2002AA301C93)
文摘To investigate the therapeutic effect of nigh-dosage γ-aminobutyric acid (GABA) on acute tetramine (TET) poisoning, 50 Kunming mice were divided into 5 groups at random and the antidotal effects of GABA or sodium dimercaptopropane sulfonate (Na-DMPS) on poisoned mice in different groups were observed in order to compare the therapeutic effects of nigh-dosage GABA with those of Na-DMPS. Slices of brain tissue of the poisoned mice were made to examine pathological changes of cells. The survival analysis was employed. Our results showed that both high-dosage GABA and Na-DMPS could obviously prolong the survival time, delay onset of convulsion and muscular twitch, and ameliorate the symptoms after acute tetramine poisoning in the mice. Better effects could be achieved with earlier use of high dosage GABA or Na-DMPS. There was no significant difference in prolonging the survival time between high-dose GABA and Na-DMPS used immediately after poisioning. It is concluded that high-dosage GABA can effectively antagonize acute toxicity of terarnine in mice. And it is suggested that nigh-dosage GABA may be used as an excellent antidote for acute TET poisoning in clinical practice. The indications and correct dosage for clinical use awaits to be further studied.
文摘Wolframite notation with benzyl arsonic acid and sodium butyl xanthate is studied,at first.It shows the efficiency of mineral processig is good when the two agents are added together.Then the synergism of sodium butyl xanthate and benzyl arsonic acid is studied also by HPLC.
基金Funded by the Ministry of Science and Technology(MOST)of China(No.2018YFB1502104)the National Natural Science Foundation of China(No.21771006)the Equipment Development Department of People’s Republic of China Central Military Commission(Pre-research Project of the Thirteenth FiveYear Plan)(No.41421020103)。
文摘We reported an inexpensive and high-efficiency hydrogen generation method from NaBH4 hydrolysis promoted by oxalic acid.NaBH4 and H2C2O4 were premixed and hydrogen generation was initiated by adding water into the solid mixture.H2C2O4 was selected as the acid promotor due to its solid state and low mass per proton.The effect of reactant ratio on the hydrogen yield and hydrogen storage density was investigated.With optimized reactant ratio,high gravimetric hydrogen storage up to 4.4wt%based on all the reactants can be achieved with excellent hydrogen generation kinetics.
文摘There were several techniques determined for the analysis of citrate and citric acid mixtures in the pharmaceutical dosage forms. Titration methods, photometric and ion chromatographic methods were used for their determination. These methods will restrict too many factors where the accurate quantification of citrate and citric acid is extremely challenging. Citric acid is the natural flavor used as a preservative for many pharmaceutical applications. Deformulation techniques used for the manufacturing of generic drugs require authentic data for their regulatory submissions. Simple accurate and reproducible validated method developed for the determination of citric acid and sodium citrate by titration followed by HPLC analysis. Free citric acid was determined by the titration method and total citric acid was determined by HPLC analysis. After subtracting the free citric acid from total citric acid content, citric acid present in the sodium citrate content was determined. Sodium citrate content was determined by applying sodium correction factor to the subtracted value of the citric acid. The results met all the validation parameters and the method was successfully measured the amount of citric acid and sodium citrate in the marketed ophthalmic/oral solutions.
文摘This paper reports the ultrastructural changes of trichomonas vaginaiis (T. vag. ) under the action of s-(-)usnic acid sodium in vitro. These changes can be shown by the following results:At first, the degranulation of the rough endoplasmic reticulum (RER) took place, the polyribosomes disaggregated. And then, the Golgi complex and the endoplasmic reticulum dilated. The cytoplasmic matrix presented and inhomogeneous apperance. Finally, the biomembrane loosed and fractured.The cell nuclei presented the karyorrhexis.
文摘BACKGROUND Bowel preparation in children can be challenging.AIM To describe the efficacy, safety, and tolerability of sodium picosulfate, magnesium oxide, and citric acid(SPMC) bowel preparation in children.METHODS Phase 3, randomized, assessor-blinded, multicenter study of low-volume, divided dose SPMC enrolled children 9-16 years undergoing elective colonoscopy. Participants 9-12 years were randomized 1:1:1 to SPMC ? dose × 2, SPMC 1 dose × 2, or polyethylene glycol(PEG). Participants 13-16 years were randomized 1:1 to SPMC 1 dose × 2 or PEG. PEG-based bowel preparations were administered per local protocol. Primary efficacy endpoint for quality of bowel preparation was responders(rating of ‘excellent' or ‘good') by modified Aronchick Scale. Secondary efficacy endpoint was participant's tolerability and satisfaction from a 7-item questionnaire. Safety assessments included adverse events(AEs) and laboratory evaluations.RESULTS 78 participants were randomized, 48 were 9-12 years, 30 were 13-16 years. For the primary efficacy endpoint in 9-12 years, 50.0%, 87.5%, and 81.3% were responders for SPMC ? dose × 2, SPMC 1 dose × 2, and PEG groups, respectively. Responder rates for 13-16 years were 81.3% for SPMC 1 dose × 2 and 85.7% for PEG. Overall, 43.8% of participants receiving SPMC 1 dose × 2 reported it was ‘very easy' or ‘easy' to drink, compared with 20.0% receiving PEG. Treatment-emergent AEs were reported by 45.5% of participants receiving SPMC 1 dose × 2 and 63.0% receiving PEG.CONCLUSION SPMC was an efficacious and safe for bowel preparation in children 9-16 years, with comparable efficacy to PEG. Tolerability for SPMC was higher compared to PEG.
基金the support of Key Laboratory of Chinese Medicine Preparation of Solid Dispersion,Gansu Longshenrongfa Pharmaceutical Industry Co.,Ltd.,Gansu Province,China
文摘As a mono-sodium salt form of alendronic acid,alendronate sodium presents multi-level ionization for the dissociation of its four hydroxyl groups.The dissociation constants of alendronate sodium were determined in this work by studying the piecewise linear relationship between volume of titrant and p H value based on acidbase potentiometric titration reaction.The distribution curves of alendronate sodium were drawn according to the determined p Ka values.There were 4 dissociation constants(pKa_1=2.43,pKa_2=7.55,pKa_3=10.80,pKa_4=11.99,respectively) of alendronate sodium,and 12 existing forms,of which 4 could be ignored,existing in different p H environments.