Aim To determine and analyze fatty acids, amino acids and trace elements of Hirudinaria manillensis. Methods Contents of fatty acids, amino acids and trace elements were determined by GC/MS, HPLC and ICP-AES. Results ...Aim To determine and analyze fatty acids, amino acids and trace elements of Hirudinaria manillensis. Methods Contents of fatty acids, amino acids and trace elements were determined by GC/MS, HPLC and ICP-AES. Results H. manillensis contained sixteen fatty acids, among which the percentage of unsaturated fatty acids is 34.05%. The eighteen amino acids were detected, which included eight essential amino acids in human body with a ratio of 33.53 %. There were eight trace elements (Ca, Cr, Cu, Fe, Mg, Mn, V and Zn) from H. manillensis, and the content of Ca, Zn and Fe were apparently higher than those of other elements. Conclusion These methods are simple and accurate. This study reports routine quantitative methods for the analysis of multiple components in H. manillensis by GC/MS, HPLC and ICP-AES.展开更多
Microcystin-RR(MC-RR),a form of microcystin with two arginine moieties,is a cyanobacterial toxin that has been detected across a wide geographic range.It is a great concern globally because of its potential liver to...Microcystin-RR(MC-RR),a form of microcystin with two arginine moieties,is a cyanobacterial toxin that has been detected across a wide geographic range.It is a great concern globally because of its potential liver toxicity.Herein,the abilities of BiVO4,Ag-BiVO4,Ag2O-BiVO4 and Ag/Ag2O-BiVO4 to photocatalytically degrade MC-RR under visible-light irradiation(λ≥420 nm) were investigated and compared.The possible degradation pathways were explored through analysis of the reaction intermediates by high-performance liquid chromatography-mass spectrometry.The results showed that the presence of Ag^0 enhanced the photocatalytic efficiency of Ag/Ag2O-BiVO4 via a synergetic effect between Ag2O and Ag^0 at the p-n heterojunction.Moreover,the presence of Ag^0 also greatly promoted the adsorption of MC-RR on the photocatalyst surface.Toxicological experiments on mice showed that the toxicity of MC-RR was significantly reduced after photocatalytic degradation.展开更多
With the increased pace of life and improved consumption level of people, the demand for food developed from natural resources is increasing day by day. Related researches have shown that the nutrition level of specia...With the increased pace of life and improved consumption level of people, the demand for food developed from natural resources is increasing day by day. Related researches have shown that the nutrition level of special wheat is higher than that of common wheat. Special wheat can improve the nutritional structure and diet quality of people. However, the researches on special wheat are rare at home and abroad. Compared with the common wheat, special wheat still faces many challenges in taste quality, storage stability, processing suitability as main food, etc. This paper summarized the researches on analysis and application of special wheat nutrition components at home and abroad so as to evaluate comprehensively the development prospect of special wheat.展开更多
AIM: To prepare polylactic acid microspheres of Erythromycin for Lung targeting. METHEDS: The orthogonal test design was used to optimize the technology of preparation. The character of the microspheres, drug release ...AIM: To prepare polylactic acid microspheres of Erythromycin for Lung targeting. METHEDS: The orthogonal test design was used to optimize the technology of preparation. The character of the microspheres, drug release in vitro, stability and tissue distribution were examined. RESULTS: The Erythromycin polylactic acid microspheres was regular in its morphology. Drug was enveloped in microspheres but not physically mixed with PDLLA. The average particle size was 11.65mm with over 94% of the microspheres being in the range of 5~20mm; The drug loading and the incorporation efficiency were 18% and 60% respectively. The microspheres were stable for three month at 4℃ and room temperature. The in vitro release properties could be expressed by the Higuchi抯 equation: y = 28.067 + 3.8515t1/2 (r = 0.9834). Comparing with injection, the drug in microspheres was more concentrated in lung tissue. CONCLUSION: Erythromycin polylactic acid microspheres showed significant sustained release and lung targeting.展开更多
Insect's nutrient composition may provide a good source of macro- and micro-nutrients with nutraceutical functions that could help people from semirural areas, such as Ixcaquixtla, located southeast of the Puebla Sta...Insect's nutrient composition may provide a good source of macro- and micro-nutrients with nutraceutical functions that could help people from semirural areas, such as Ixcaquixtla, located southeast of the Puebla State, Mexico. The aim of this study was to assess macro- and micro-nutrients in Cuetlas (Arsenura armada C.) larvae and inform local people about the nutraceutical benefits that those insects could provide. Cuetlas larvae samples were collected from Jonote tree on August, 2014 to analyze minerals and macro-nutrient of raw larvae according to AOAC (1995) techniques. Results showed that Cuetlas larvae contained 56.93% proteins, 14.76% lipids, 2.95% minerals, 2.13% fiber and 23.23% soluble carbohydrates. Cuetlas larvae have a good amount of proteins, essential macromolecules for human life as well as essential fatty acids that are important sources of fuel for brain cells and in particular for cardiac and skeletal muscle, minerals, not determined individually, which are important for metabolism processes, fiber for digestive processes and soluble carbohydrates as energy source.展开更多
This study investigate the effect of the concentration of nitrate and phosphate, present in the culture medium, on the chemical and biochemical composition of the products from the marine microalgae, Nannochloropsis s...This study investigate the effect of the concentration of nitrate and phosphate, present in the culture medium, on the chemical and biochemical composition of the products from the marine microalgae, Nannochloropsis sp.. Experimental design allowed the assessment, in a systematic way, of the response of the microalgae to the nitrate and phosphate concentrations, and the way they lead to changes in the total amount of carotenoids, chlorophyll a, iron and magnesium produced or uptaken. The total carotenoids presented a higher yield when cultivated under lower phosphate concentrations, but showed no change with nitrate concentration. Chlorophyll a yield increased in the presence of higher concentrations of nitrogen and lower concentrations of phosphorus. There was an increase in the amount of iron absorbed by cells when higher levels of nitrates were present, but the effect is insignificant with phosphates. The magnesium content was not significantly affected by culture manipulation. The results also showed that the biomass yield of the microalgae Nannochloropsis sp. was negatively affected by the N/P ratio. The antioxidative potential of the microalgae, in contrast, was found to increase with the N/P ratio.展开更多
The microstructure, dielectric properties and chemical state of Ti element on BaTi_4O_9 (f)/(0.64 BaTi_4O_9-0.36BaPr_2Ti_4O_(12)) composites sample surface were characterized by X-ray diffraction (XRD), Transmission e...The microstructure, dielectric properties and chemical state of Ti element on BaTi_4O_9 (f)/(0.64 BaTi_4O_9-0.36BaPr_2Ti_4O_(12)) composites sample surface were characterized by X-ray diffraction (XRD), Transmission electron microscopy (TEM), LCR meter method and X-ray photoelectron spectroscopy (XPS). The results show that the system is composed of BaTi_4O_9 and BaPr_2Ti_4O_(12) two phases. Pr ions are distributed in the BaWi_4O_9 grains and the segregation of Pr ions was observed on the grain boundaries of BaTi_4O_9/BaTi_4O_9. The content of Ti^(3+) and Ti^(2+) decrease in the BPT system composites due to the addition of BaTi_4O_9 fibers, which improved the dielectric properties of the system. BPT10 sample with 10% BaTi_4O_9 fibers, has the best dielectric properties in the system, its ε_r = 64, tan δ= 1×10^(-4)(at 1 MHz) , and it may be a potential candidate for microwave dielectric ceramics.展开更多
This paper describes an innovative method for the immobilization of acylase I, which was entrapped into the CA-CTA micropore membrane. The most suitable casting solutions proportion for immobilizing the enzyme was obt...This paper describes an innovative method for the immobilization of acylase I, which was entrapped into the CA-CTA micropore membrane. The most suitable casting solutions proportion for immobilizing the enzyme was obtained through orthogonal experiment. Properties of the enzyme membrane were investigated and compared with those of free enzyme and blank membrane. The thermal stability and pH stability of the enzyme inside the membrane were changed by immobilization. The optimum pH was found to be 6.0, which changes 1.0 unit compared with that of free acylase I. The optimum temperature was found to be about 90℃, which is higher than that of free acylase I (60℃). Experimental results showed that immobilization had effects on the kinetic parameters of acylase I.展开更多
In the established apparatus, the conversion ratios of cellulose sulfation (X) under different sulfation conditions were measured. The range of temperature was from -5℃ to +5℃, and the H2SO4 concentration was from 3...In the established apparatus, the conversion ratios of cellulose sulfation (X) under different sulfation conditions were measured. The range of temperature was from -5℃ to +5℃, and the H2SO4 concentration was from 3.1 mol·L-1 to 4.5mol·L-1. The experimental results were used for the establishment of the kinetic model for cellulose sulfation. With the model, X values and the yield of NaCS (Y) can be calculated, thus the reaction with respect to H2SO4 concentration is determined to be third order.展开更多
Covalent modification of bovine testicular hyaluronidase with chondroitin sulphate led to changes in the pattern of glycation of native and modified enzyme in its reaction with neutral saccharides and N-acetylhexosami...Covalent modification of bovine testicular hyaluronidase with chondroitin sulphate led to changes in the pattern of glycation of native and modified enzyme in its reaction with neutral saccharides and N-acetylhexosamines. Thus, mono- and di-saccharides inactivated the native hyaluronidase to a greater extent than the chondroitin sulfate-modified enzyme. N-acetylhexosamine, on the opposite, inactivated the modified hyaluronidase to a greater extent than the native one. These properties made it possible to use native and modified hyaluronidase as an informative research system for in vivo measurement of the predominant type of saccharide agents in the circulation. The proposed approach was experimentally substantiated by obtained results of the study on these interactions of hyaluronidase derivatives with hyaluronan fragments and their mixture. In a model of post-ischemic perfusion of the rat limb, the effect of hyaluronidase derivatives and their components on restoration of the microcirculation were tracked using laser Doppler flowmetry. Native hyaluronidase accelerated the restoration of initial level of microcirculation, but modified enzyme was markedly inhibited by glycocalyx degradation products. N-acetylhexosamine was positioned at the reducing terminal of these products as a natural label for these glycocalyx fragments. These and other data obtained under various experimental conditions supported the participation of endothelial glycocalyx in microcirculation disturbances.展开更多
A striking feature of the Mongolian plateau is the wide range of air temperatures during a year, -30 to 30~C. High summer temperatures, atmospheric weathering and the arid climate lead to formation of numerous alkalin...A striking feature of the Mongolian plateau is the wide range of air temperatures during a year, -30 to 30~C. High summer temperatures, atmospheric weathering and the arid climate lead to formation of numerous alkaline soda lakes that are covered by ice during 6-7 months per year. During the study period, the lakes had pH values between 8.1 to 10.4 and salinity between 1.8 and 360 g/L. According to chemical composition, the lakes belong to sodium carbonate, sodium chloride-carbonate and sodium sulfate-carbonate types. This paper presents the data on the water chemical composition, results of the determination of the rates of microbial processes in microbial mats and sediments in the lakes studied, and the results of a Principal Component Analysis of environmental variables and microbial activity data. Temperature was the most important factor that influenced both chemical composition and microbial activity, pH and salinity are also important factors for the microbial processes. Dark CO2 fixation is impacted mostly by salinity and the chemical composition of the lake water. Total photosynthesis and sulfate-reduction are impacted mostly by pH. Photosynthesis is the dominant process of primary production, but the highest rate (386 mg C/(L.d)) determined in the lakes studied were 2-3 times lower than in microbial mats of lakes located in tropical zones. This can be explained by the relatively short warm period that lasts only 3-4 months per year. The highest measured rate of dark CO2 assimilation (59.8 mg C/(L·d)) was much lower than photosynthesis. The highest rate of sulfate reduction was 60 mg S/(L·d), while that of methanogenesis was 75.6 μL CH4/(L·d) in the alkaline lakes of Mongolian plateau. The rate of organic matter consumption during sulfate reduction was 3-4 orders of magnitude higher than that associated with methanogenesis.展开更多
Polymeric biosurfactants were prepared by the transesterification reaction between vinyl laurate (VILA) and carboxymethylcellulose (CMC). The reaction was performed in two different reaction media ((A) DMF/pTSA...Polymeric biosurfactants were prepared by the transesterification reaction between vinyl laurate (VILA) and carboxymethylcellulose (CMC). The reaction was performed in two different reaction media ((A) DMF/pTSA and (B) DMF/K2CO3) at various reaction conditions and using microwave radiation with controlled power as heating source. The obtained water-soluble VILA-CMC derivatives were characterized by FT-IR spectroscopy and their surface-active properties evaluated. All derivatives showed a very low esterification extent and moderate surface tension lowering effect. Nevertheless, they exhibited significant emulsifying efficiency comparable to that of the synthetic surfactant, Tween 20. The results suggested that suitable surface-active VILA-CMC derivatives can be prepared under microwave heating at low microwave power and reaction times in the range of few minutes, which represents a great advantage in comparison to transesterification reactions lasting up to 6 h at conventional heating.展开更多
Micronutrient status in soils can be affected by long-term fertilization and intensive cropping.A 19-year experiment (1990-2008) was carried out to investigate the influence of different fertilization regimes on micro...Micronutrient status in soils can be affected by long-term fertilization and intensive cropping.A 19-year experiment (1990-2008) was carried out to investigate the influence of different fertilization regimes on micronutrients in an Aquic Inceptisol and maize and wheat grains in Zhengzhou,China.The results showed that soil total Cu and Zn markedly declined after 19 years with application of N fertilizer alone.Soil total Fe and Mn were significantly increased mainly due to atmospheric deposition.Applications of P and organic fertilizer with incorporation of straws resulted in dramatic increases in soil total Cu,Zn,Fe,and Mn.Soil diethylenetriamine pentaacetic acid (DTPA)-extractable Cu in all treatments sharply decreased from initially 1.12 to about 0.8 mg kg -1 .The treatments with organic fertilizer had the highest soil DTPA-extractable Cu,Zn,Fe,and Mn after 19 years of cropping and fertilization,thus demonstrating the important role of organic fertilizer application in improving available micronutrient status.Cu and Zn contents in wheat grains in the no-P treatments were significantly higher than those of the treatments with P application.In addition,Fe and Mn contents in wheat grains were positively correlated with their soil DTPA-extractable concentrations.These indicated that the long-term application of organic fertilizer resulted in significant increases in soil total and available micronutrient concentrations and remarkable reduction in wheat grain Cu and Zn contents,which was due to high soil available P.展开更多
Objective:To study the relationship between plasma adiponectin concentration and the functional activities of circulating endothelial progenitor cells(EPCs) in patients with coronary artery disease(CAD).Methods:Circul...Objective:To study the relationship between plasma adiponectin concentration and the functional activities of circulating endothelial progenitor cells(EPCs) in patients with coronary artery disease(CAD).Methods:Circulating EPCs were enumerated as AC133+/KDR+ cells via flow cytometry and identified by co-staining with DiI-acLDL and fluorescein isothiocy-anate(FITC)-conjugated lectin under a fluorescent microscope.The migratory capacity of EPCs was measured by modified Boyden chamber assay.Adhesion capacity was performed to count adherent cells after replating EPCs on six-well culture dishes coated with fibronectin.Results:The number of circulating EPCs(AC133+/KDR+ cells) decreased significantly in CAD patients,compared with control subjects [(74.2±12.3) vs(83.5±12.9) cells/ml blood,P<0.01].In addition,the number of EPCs also decreased in CAD patients after ex vivo cultivation [(54.4±8.6) vs(71.9±11.6) EPCs/field,P<0.01].Both circulating EPCs and differentiated EPCs were positively correlated with plasma adiponectin concentration.The functional activities of EPCs from CAD patients,such as migratory and adherent capacities,were also impaired,compared with control subjects,and positively correlated with plasma adiponectin concentration.Conclusion:The study demonstrates that the impairment of the number and functional activities of EPCs in CAD patients is correlated with their lower plasma adiponectin concentrations.展开更多
Elemental sulfur(ES) is one of the intermediates in the inorganic sulfur cycle and thus plays a key role in the fractionation of stable sulfur isotopes in different reservoirs and the marine environment. In this study...Elemental sulfur(ES) is one of the intermediates in the inorganic sulfur cycle and thus plays a key role in the fractionation of stable sulfur isotopes in different reservoirs and the marine environment. In this study, solid ES is discovered in sediments near the Jiulong Methane Reef in the northern South China Sea by scanning electron microscopy and Raman spectroscopy. Combining the morphology and distribution of ES, pyrite concentrations, and sulfur isotopes, we conclude that:(1) solid ES coexists with pyrite microcrystals and sulfide(oxyhydr)oxides as well as clay minerals, and they are mainly distributed on the surface of mineral aggregates;(2) ES mainly occurs within and near the sulfate-methane transition zone(SMTZ) despite little morphological diversity;(3) ES formation might be related to hydrogen sulfide oxidation and is therefore linked with fluctuations in the SMTZ. Within the SMTZ, hydrogen sulfide is produced and pyrite precipitates because of enhanced anaerobic oxidation of methane coupled with dissimilatory sulfate reduction. This enhances the efficiency of the inorganic sulfur cycle and provides favorable conditions for ES formation. The discovery of solid ES in sediments near the Jiulong Methane Reef suggests an important relationship with SMTZ fluctuations that could have implications for the evolution of methane hydrate in the South China Sea.展开更多
The characteristics of the interactions co-cultures of ultrafine mesoporous silica nanoparticles (MSNs) and the Liriodendron hybrid suspension cells were systematically investigated using laser scanning confocal mic...The characteristics of the interactions co-cultures of ultrafine mesoporous silica nanoparticles (MSNs) and the Liriodendron hybrid suspension cells were systematically investigated using laser scanning confocal microscope (LSCM) and scanning elec- tron microscopy (SEM). Using fluorescein isothiocyanate (FITC) labeling, the LSCM observations demonstrated that MSNs (size, 5-15 nm) with attached FITC molecules efficiently penetrated walled plant cells through endocytic pathways, but free FITC could not enter the intact plant cells, The SEM measurements indicated that MSNs readily aggregated on the surface of intact plant cells, and also directly confirmed that MSNs could enter intact plant cells; this was achieved by determining the amount of silicon present. After 24 h of incubation with 1.0 mg mL-t of MSNs, the viability of the plant cells was analyzed using fluorescein diacetate staining; the results showed that these cells retained high viability, and no cell death was observed. Interestingly, after the incubation with MSNs, the Liriodendron hybrid suspension cells retained the capability for plant regen- eration via somatic embryogenesis. Our results indicate that ultrafine MSNs hold considerable potential as nano-carriers of ex- tracellular molecules, and can be used to investigate in vitro gene-delivery in plant cells.展开更多
There are many remediation techniques for organic contaminated soils,but relatively few of them are applicable to trace elementcontaminated soils.A field experiment was carried out to investigate assisted natural reme...There are many remediation techniques for organic contaminated soils,but relatively few of them are applicable to trace elementcontaminated soils.A field experiment was carried out to investigate assisted natural remediation(ANR) of an acid soil contaminated by As,Cd,Cu,Zn and Pb using one inorganic amendment,sugar beet lime(SL),and two organic amendments,biosolid compost(BC)and leonardeite(LE).The experiment was arranged in a completely randomized block design with four treatments in three replicates:1) a non-amended control(NA);2) SL amended at 30 Mg ha^(-1) year^(-1);3) BC amended at 30 Mg ha^(-1) year^(-1) and 4) LE amended at 20 Mg ha^(-1) year^(-1) plus SL amended at 10 Mg ha^(-1) year^(-1)(LESL).The amended plots received two doses of each amendment(DO2):one in October 2002 and another in October 2003.The plots were then divided in half into two subpolts and one subplot received another two doses of the same amendments(DO4) in October 2005 and October 2006.In 2011,the pH values of the amended soils were greater than that of the NA soil,with the SL-amended soil showing the highest pH.Total organic carbon(TOC) was also greater in the amended soil,and greater with DO4 than with DO2.Amendments reduced the concentrations of 0.01 mol L^(-1) CaCl_2-extractable Cd,Cu and Zn,especially in the SL-amended soil.Plant cover of colonizing vegetation was enhanced by amendments,but was independent of amendment doses.Changes in soil properties from 2003 to 2011 showed that the first amendment application of DO2 caused a high differentiation between all the amendment treatments and the NA treatment.After the second application of DO2,soil pH and TOC continued increasing slowly.Further two applications of amendments(DO4) caused differences only in the organic treatments.Plant cover increased over time in all the treatments including NA.It could be concluded that the slow and steady natural remediation of this soil could be enhanced by amendment application(ANR).展开更多
Purpose: To investigate the effects of salvianolic acid B (SAB) on tumor necrosis factor a (TNF-a) induced alterations of cerebral microcirculation with a bone-abrading model. Methods: The influences of cranioto...Purpose: To investigate the effects of salvianolic acid B (SAB) on tumor necrosis factor a (TNF-a) induced alterations of cerebral microcirculation with a bone-abrading model. Methods: The influences of craniotomy model and bone-abrading model on cerebral microcirculation were compared. The bone-abrading method was used to detect the effects of intracerebroventricular application of 40 μg/kg.bw TNF-a on cerebral venular leakage of fluorescein isothiocyanate (FITC)- albulmin and the rolling and adhesion of leukocytes on venules with fluorescence tracer rhodamine 6G, The therapeutical effects of SAB on TNF-a induced microcirculatory alteration were observed, with continuous intravenous injection of 5 mg/kg.h SAB starting at 20 min before or 20 min after TNF-a administration, respectively, The expressions of CDllb/CD18 and CD62L in leukocytes were measured with flow cytometry, Immunohistochemical staining was also used to detect E-selectin and ICAM-1 expression in endothelial cells, Results: Compared with craniotomy method, the bone-abrading method preserved a higher erythrocyte velocity in cerebral venules and more opening capillaries. TNF-a intervention only caused responses of vascular hyperpermeability and leukocyte roiling on venular walls, without leukocyte adhesion and other hemodynamic changes. Pre- or post-SAB treatment attenuated those responses and suppressed the enhanced expressions of CDII b/CDI8 and CD62L in leukocytes and E-selectin and ICAM-I in endothelial cells induced by TNF-a. Conclusions: The pre- and post-applications of SAB during TNF-a stimulation could suppress adhesive molecular expression and subsequently attenuate the increase of cerebral vascular permeability and leukocyte rolling.展开更多
We report a functionalisation strategy which is able to generate Ricinus communis agglutinin 1 (RCA 120) modified PMMA microfluidic device for binding and culturing living cells. The functionalisation is achieved by...We report a functionalisation strategy which is able to generate Ricinus communis agglutinin 1 (RCA 120) modified PMMA microfluidic device for binding and culturing living cells. The functionalisation is achieved by standard aminealdehyde (Schiff base) reaction through the crosslinker, glutaraldehyde. To prove the ability of the RCA 120 modified PMMA surface, the PC 12 cell line (rat pheochromocytoma ceils) has been captured and cultured by the microfluidic device. In the presence of tunicamycin, the dose/timedependence on decreasing of binding affinity of RCA 120 modified device with PC 12 cell is also observed. The experimental results demonstrate that the lectin-functionalized microfluidic device can be employed as efficient cell culturing platform, and has a great promise of being used as a powerful tool for monitoring the interaction of drug with living cell.展开更多
基金Department of Science & Technology of GuangdongProvince (No.0509119).
文摘Aim To determine and analyze fatty acids, amino acids and trace elements of Hirudinaria manillensis. Methods Contents of fatty acids, amino acids and trace elements were determined by GC/MS, HPLC and ICP-AES. Results H. manillensis contained sixteen fatty acids, among which the percentage of unsaturated fatty acids is 34.05%. The eighteen amino acids were detected, which included eight essential amino acids in human body with a ratio of 33.53 %. There were eight trace elements (Ca, Cr, Cu, Fe, Mg, Mn, V and Zn) from H. manillensis, and the content of Ca, Zn and Fe were apparently higher than those of other elements. Conclusion These methods are simple and accurate. This study reports routine quantitative methods for the analysis of multiple components in H. manillensis by GC/MS, HPLC and ICP-AES.
基金supported by the National Natural Science Foundation of China (21677086, 21407092, 21377067, 21577078)the Natural Science Foundation for Innovation Group of Hubei Province, China (2015CFA021)~~
文摘Microcystin-RR(MC-RR),a form of microcystin with two arginine moieties,is a cyanobacterial toxin that has been detected across a wide geographic range.It is a great concern globally because of its potential liver toxicity.Herein,the abilities of BiVO4,Ag-BiVO4,Ag2O-BiVO4 and Ag/Ag2O-BiVO4 to photocatalytically degrade MC-RR under visible-light irradiation(λ≥420 nm) were investigated and compared.The possible degradation pathways were explored through analysis of the reaction intermediates by high-performance liquid chromatography-mass spectrometry.The results showed that the presence of Ag^0 enhanced the photocatalytic efficiency of Ag/Ag2O-BiVO4 via a synergetic effect between Ag2O and Ag^0 at the p-n heterojunction.Moreover,the presence of Ag^0 also greatly promoted the adsorption of MC-RR on the photocatalyst surface.Toxicological experiments on mice showed that the toxicity of MC-RR was significantly reduced after photocatalytic degradation.
文摘With the increased pace of life and improved consumption level of people, the demand for food developed from natural resources is increasing day by day. Related researches have shown that the nutrition level of special wheat is higher than that of common wheat. Special wheat can improve the nutritional structure and diet quality of people. However, the researches on special wheat are rare at home and abroad. Compared with the common wheat, special wheat still faces many challenges in taste quality, storage stability, processing suitability as main food, etc. This paper summarized the researches on analysis and application of special wheat nutrition components at home and abroad so as to evaluate comprehensively the development prospect of special wheat.
基金Guangdong Provincial Natural Science Foundation of China
文摘AIM: To prepare polylactic acid microspheres of Erythromycin for Lung targeting. METHEDS: The orthogonal test design was used to optimize the technology of preparation. The character of the microspheres, drug release in vitro, stability and tissue distribution were examined. RESULTS: The Erythromycin polylactic acid microspheres was regular in its morphology. Drug was enveloped in microspheres but not physically mixed with PDLLA. The average particle size was 11.65mm with over 94% of the microspheres being in the range of 5~20mm; The drug loading and the incorporation efficiency were 18% and 60% respectively. The microspheres were stable for three month at 4℃ and room temperature. The in vitro release properties could be expressed by the Higuchi抯 equation: y = 28.067 + 3.8515t1/2 (r = 0.9834). Comparing with injection, the drug in microspheres was more concentrated in lung tissue. CONCLUSION: Erythromycin polylactic acid microspheres showed significant sustained release and lung targeting.
文摘Insect's nutrient composition may provide a good source of macro- and micro-nutrients with nutraceutical functions that could help people from semirural areas, such as Ixcaquixtla, located southeast of the Puebla State, Mexico. The aim of this study was to assess macro- and micro-nutrients in Cuetlas (Arsenura armada C.) larvae and inform local people about the nutraceutical benefits that those insects could provide. Cuetlas larvae samples were collected from Jonote tree on August, 2014 to analyze minerals and macro-nutrient of raw larvae according to AOAC (1995) techniques. Results showed that Cuetlas larvae contained 56.93% proteins, 14.76% lipids, 2.95% minerals, 2.13% fiber and 23.23% soluble carbohydrates. Cuetlas larvae have a good amount of proteins, essential macromolecules for human life as well as essential fatty acids that are important sources of fuel for brain cells and in particular for cardiac and skeletal muscle, minerals, not determined individually, which are important for metabolism processes, fiber for digestive processes and soluble carbohydrates as energy source.
文摘This study investigate the effect of the concentration of nitrate and phosphate, present in the culture medium, on the chemical and biochemical composition of the products from the marine microalgae, Nannochloropsis sp.. Experimental design allowed the assessment, in a systematic way, of the response of the microalgae to the nitrate and phosphate concentrations, and the way they lead to changes in the total amount of carotenoids, chlorophyll a, iron and magnesium produced or uptaken. The total carotenoids presented a higher yield when cultivated under lower phosphate concentrations, but showed no change with nitrate concentration. Chlorophyll a yield increased in the presence of higher concentrations of nitrogen and lower concentrations of phosphorus. There was an increase in the amount of iron absorbed by cells when higher levels of nitrates were present, but the effect is insignificant with phosphates. The magnesium content was not significantly affected by culture manipulation. The results also showed that the biomass yield of the microalgae Nannochloropsis sp. was negatively affected by the N/P ratio. The antioxidative potential of the microalgae, in contrast, was found to increase with the N/P ratio.
文摘The microstructure, dielectric properties and chemical state of Ti element on BaTi_4O_9 (f)/(0.64 BaTi_4O_9-0.36BaPr_2Ti_4O_(12)) composites sample surface were characterized by X-ray diffraction (XRD), Transmission electron microscopy (TEM), LCR meter method and X-ray photoelectron spectroscopy (XPS). The results show that the system is composed of BaTi_4O_9 and BaPr_2Ti_4O_(12) two phases. Pr ions are distributed in the BaWi_4O_9 grains and the segregation of Pr ions was observed on the grain boundaries of BaTi_4O_9/BaTi_4O_9. The content of Ti^(3+) and Ti^(2+) decrease in the BPT system composites due to the addition of BaTi_4O_9 fibers, which improved the dielectric properties of the system. BPT10 sample with 10% BaTi_4O_9 fibers, has the best dielectric properties in the system, its ε_r = 64, tan δ= 1×10^(-4)(at 1 MHz) , and it may be a potential candidate for microwave dielectric ceramics.
文摘This paper describes an innovative method for the immobilization of acylase I, which was entrapped into the CA-CTA micropore membrane. The most suitable casting solutions proportion for immobilizing the enzyme was obtained through orthogonal experiment. Properties of the enzyme membrane were investigated and compared with those of free enzyme and blank membrane. The thermal stability and pH stability of the enzyme inside the membrane were changed by immobilization. The optimum pH was found to be 6.0, which changes 1.0 unit compared with that of free acylase I. The optimum temperature was found to be about 90℃, which is higher than that of free acylase I (60℃). Experimental results showed that immobilization had effects on the kinetic parameters of acylase I.
基金Supported by the National Natural Science Foundation of China(No.29676069).
文摘In the established apparatus, the conversion ratios of cellulose sulfation (X) under different sulfation conditions were measured. The range of temperature was from -5℃ to +5℃, and the H2SO4 concentration was from 3.1 mol·L-1 to 4.5mol·L-1. The experimental results were used for the establishment of the kinetic model for cellulose sulfation. With the model, X values and the yield of NaCS (Y) can be calculated, thus the reaction with respect to H2SO4 concentration is determined to be third order.
文摘Covalent modification of bovine testicular hyaluronidase with chondroitin sulphate led to changes in the pattern of glycation of native and modified enzyme in its reaction with neutral saccharides and N-acetylhexosamines. Thus, mono- and di-saccharides inactivated the native hyaluronidase to a greater extent than the chondroitin sulfate-modified enzyme. N-acetylhexosamine, on the opposite, inactivated the modified hyaluronidase to a greater extent than the native one. These properties made it possible to use native and modified hyaluronidase as an informative research system for in vivo measurement of the predominant type of saccharide agents in the circulation. The proposed approach was experimentally substantiated by obtained results of the study on these interactions of hyaluronidase derivatives with hyaluronan fragments and their mixture. In a model of post-ischemic perfusion of the rat limb, the effect of hyaluronidase derivatives and their components on restoration of the microcirculation were tracked using laser Doppler flowmetry. Native hyaluronidase accelerated the restoration of initial level of microcirculation, but modified enzyme was markedly inhibited by glycocalyx degradation products. N-acetylhexosamine was positioned at the reducing terminal of these products as a natural label for these glycocalyx fragments. These and other data obtained under various experimental conditions supported the participation of endothelial glycocalyx in microcirculation disturbances.
基金Supported by the Ministry of Education and Science of the Russian Federation(No.1990)the Russian Foundation for Basic Research(No.13-04-00646)the Presidium of the Russian Academy of Sciences Program No.28"Biosphere Origin and Evolution"
文摘A striking feature of the Mongolian plateau is the wide range of air temperatures during a year, -30 to 30~C. High summer temperatures, atmospheric weathering and the arid climate lead to formation of numerous alkaline soda lakes that are covered by ice during 6-7 months per year. During the study period, the lakes had pH values between 8.1 to 10.4 and salinity between 1.8 and 360 g/L. According to chemical composition, the lakes belong to sodium carbonate, sodium chloride-carbonate and sodium sulfate-carbonate types. This paper presents the data on the water chemical composition, results of the determination of the rates of microbial processes in microbial mats and sediments in the lakes studied, and the results of a Principal Component Analysis of environmental variables and microbial activity data. Temperature was the most important factor that influenced both chemical composition and microbial activity, pH and salinity are also important factors for the microbial processes. Dark CO2 fixation is impacted mostly by salinity and the chemical composition of the lake water. Total photosynthesis and sulfate-reduction are impacted mostly by pH. Photosynthesis is the dominant process of primary production, but the highest rate (386 mg C/(L.d)) determined in the lakes studied were 2-3 times lower than in microbial mats of lakes located in tropical zones. This can be explained by the relatively short warm period that lasts only 3-4 months per year. The highest measured rate of dark CO2 assimilation (59.8 mg C/(L·d)) was much lower than photosynthesis. The highest rate of sulfate reduction was 60 mg S/(L·d), while that of methanogenesis was 75.6 μL CH4/(L·d) in the alkaline lakes of Mongolian plateau. The rate of organic matter consumption during sulfate reduction was 3-4 orders of magnitude higher than that associated with methanogenesis.
文摘Polymeric biosurfactants were prepared by the transesterification reaction between vinyl laurate (VILA) and carboxymethylcellulose (CMC). The reaction was performed in two different reaction media ((A) DMF/pTSA and (B) DMF/K2CO3) at various reaction conditions and using microwave radiation with controlled power as heating source. The obtained water-soluble VILA-CMC derivatives were characterized by FT-IR spectroscopy and their surface-active properties evaluated. All derivatives showed a very low esterification extent and moderate surface tension lowering effect. Nevertheless, they exhibited significant emulsifying efficiency comparable to that of the synthetic surfactant, Tween 20. The results suggested that suitable surface-active VILA-CMC derivatives can be prepared under microwave heating at low microwave power and reaction times in the range of few minutes, which represents a great advantage in comparison to transesterification reactions lasting up to 6 h at conventional heating.
基金Supported by the National Key Technology R&D Program of China (No. 2006BAD05B04)the Earmarked Fund for Modern Agro-Industry Technology Research System of China
文摘Micronutrient status in soils can be affected by long-term fertilization and intensive cropping.A 19-year experiment (1990-2008) was carried out to investigate the influence of different fertilization regimes on micronutrients in an Aquic Inceptisol and maize and wheat grains in Zhengzhou,China.The results showed that soil total Cu and Zn markedly declined after 19 years with application of N fertilizer alone.Soil total Fe and Mn were significantly increased mainly due to atmospheric deposition.Applications of P and organic fertilizer with incorporation of straws resulted in dramatic increases in soil total Cu,Zn,Fe,and Mn.Soil diethylenetriamine pentaacetic acid (DTPA)-extractable Cu in all treatments sharply decreased from initially 1.12 to about 0.8 mg kg -1 .The treatments with organic fertilizer had the highest soil DTPA-extractable Cu,Zn,Fe,and Mn after 19 years of cropping and fertilization,thus demonstrating the important role of organic fertilizer application in improving available micronutrient status.Cu and Zn contents in wheat grains in the no-P treatments were significantly higher than those of the treatments with P application.In addition,Fe and Mn contents in wheat grains were positively correlated with their soil DTPA-extractable concentrations.These indicated that the long-term application of organic fertilizer resulted in significant increases in soil total and available micronutrient concentrations and remarkable reduction in wheat grain Cu and Zn contents,which was due to high soil available P.
文摘Objective:To study the relationship between plasma adiponectin concentration and the functional activities of circulating endothelial progenitor cells(EPCs) in patients with coronary artery disease(CAD).Methods:Circulating EPCs were enumerated as AC133+/KDR+ cells via flow cytometry and identified by co-staining with DiI-acLDL and fluorescein isothiocy-anate(FITC)-conjugated lectin under a fluorescent microscope.The migratory capacity of EPCs was measured by modified Boyden chamber assay.Adhesion capacity was performed to count adherent cells after replating EPCs on six-well culture dishes coated with fibronectin.Results:The number of circulating EPCs(AC133+/KDR+ cells) decreased significantly in CAD patients,compared with control subjects [(74.2±12.3) vs(83.5±12.9) cells/ml blood,P<0.01].In addition,the number of EPCs also decreased in CAD patients after ex vivo cultivation [(54.4±8.6) vs(71.9±11.6) EPCs/field,P<0.01].Both circulating EPCs and differentiated EPCs were positively correlated with plasma adiponectin concentration.The functional activities of EPCs from CAD patients,such as migratory and adherent capacities,were also impaired,compared with control subjects,and positively correlated with plasma adiponectin concentration.Conclusion:The study demonstrates that the impairment of the number and functional activities of EPCs in CAD patients is correlated with their lower plasma adiponectin concentrations.
基金supported by the National Natural Science Foundation of China(Grants Nos.41472085 and 41172102)the National Basic Research Program of China(Grants Nos.2011CB808805 and 2009CB21950605)the National Project of Exploration and Test Production for Gas Hydrate(Grants Nos.GZH20110030-50603 and GZH20110030-6WX02)
文摘Elemental sulfur(ES) is one of the intermediates in the inorganic sulfur cycle and thus plays a key role in the fractionation of stable sulfur isotopes in different reservoirs and the marine environment. In this study, solid ES is discovered in sediments near the Jiulong Methane Reef in the northern South China Sea by scanning electron microscopy and Raman spectroscopy. Combining the morphology and distribution of ES, pyrite concentrations, and sulfur isotopes, we conclude that:(1) solid ES coexists with pyrite microcrystals and sulfide(oxyhydr)oxides as well as clay minerals, and they are mainly distributed on the surface of mineral aggregates;(2) ES mainly occurs within and near the sulfate-methane transition zone(SMTZ) despite little morphological diversity;(3) ES formation might be related to hydrogen sulfide oxidation and is therefore linked with fluctuations in the SMTZ. Within the SMTZ, hydrogen sulfide is produced and pyrite precipitates because of enhanced anaerobic oxidation of methane coupled with dissimilatory sulfate reduction. This enhances the efficiency of the inorganic sulfur cycle and provides favorable conditions for ES formation. The discovery of solid ES in sediments near the Jiulong Methane Reef suggests an important relationship with SMTZ fluctuations that could have implications for the evolution of methane hydrate in the South China Sea.
基金supported by the National Natural Science Foundation of China (30930077,31000164)
文摘The characteristics of the interactions co-cultures of ultrafine mesoporous silica nanoparticles (MSNs) and the Liriodendron hybrid suspension cells were systematically investigated using laser scanning confocal microscope (LSCM) and scanning elec- tron microscopy (SEM). Using fluorescein isothiocyanate (FITC) labeling, the LSCM observations demonstrated that MSNs (size, 5-15 nm) with attached FITC molecules efficiently penetrated walled plant cells through endocytic pathways, but free FITC could not enter the intact plant cells, The SEM measurements indicated that MSNs readily aggregated on the surface of intact plant cells, and also directly confirmed that MSNs could enter intact plant cells; this was achieved by determining the amount of silicon present. After 24 h of incubation with 1.0 mg mL-t of MSNs, the viability of the plant cells was analyzed using fluorescein diacetate staining; the results showed that these cells retained high viability, and no cell death was observed. Interestingly, after the incubation with MSNs, the Liriodendron hybrid suspension cells retained the capability for plant regen- eration via somatic embryogenesis. Our results indicate that ultrafine MSNs hold considerable potential as nano-carriers of ex- tracellular molecules, and can be used to investigate in vitro gene-delivery in plant cells.
基金supported by the Programa Operativo Feder de Andalucia 2007-2013 of Sapin (No.PAIDI AGR108)the Project of the Plan Nacional de Investigacion of Spain(No.AGL201123617)
文摘There are many remediation techniques for organic contaminated soils,but relatively few of them are applicable to trace elementcontaminated soils.A field experiment was carried out to investigate assisted natural remediation(ANR) of an acid soil contaminated by As,Cd,Cu,Zn and Pb using one inorganic amendment,sugar beet lime(SL),and two organic amendments,biosolid compost(BC)and leonardeite(LE).The experiment was arranged in a completely randomized block design with four treatments in three replicates:1) a non-amended control(NA);2) SL amended at 30 Mg ha^(-1) year^(-1);3) BC amended at 30 Mg ha^(-1) year^(-1) and 4) LE amended at 20 Mg ha^(-1) year^(-1) plus SL amended at 10 Mg ha^(-1) year^(-1)(LESL).The amended plots received two doses of each amendment(DO2):one in October 2002 and another in October 2003.The plots were then divided in half into two subpolts and one subplot received another two doses of the same amendments(DO4) in October 2005 and October 2006.In 2011,the pH values of the amended soils were greater than that of the NA soil,with the SL-amended soil showing the highest pH.Total organic carbon(TOC) was also greater in the amended soil,and greater with DO4 than with DO2.Amendments reduced the concentrations of 0.01 mol L^(-1) CaCl_2-extractable Cd,Cu and Zn,especially in the SL-amended soil.Plant cover of colonizing vegetation was enhanced by amendments,but was independent of amendment doses.Changes in soil properties from 2003 to 2011 showed that the first amendment application of DO2 caused a high differentiation between all the amendment treatments and the NA treatment.After the second application of DO2,soil pH and TOC continued increasing slowly.Further two applications of amendments(DO4) caused differences only in the organic treatments.Plant cover increased over time in all the treatments including NA.It could be concluded that the slow and steady natural remediation of this soil could be enhanced by amendment application(ANR).
基金This study was supported by the General Program from the Natural Science Foundation of China,Southern Medical University Research Program for Young Scientists Training
文摘Purpose: To investigate the effects of salvianolic acid B (SAB) on tumor necrosis factor a (TNF-a) induced alterations of cerebral microcirculation with a bone-abrading model. Methods: The influences of craniotomy model and bone-abrading model on cerebral microcirculation were compared. The bone-abrading method was used to detect the effects of intracerebroventricular application of 40 μg/kg.bw TNF-a on cerebral venular leakage of fluorescein isothiocyanate (FITC)- albulmin and the rolling and adhesion of leukocytes on venules with fluorescence tracer rhodamine 6G, The therapeutical effects of SAB on TNF-a induced microcirculatory alteration were observed, with continuous intravenous injection of 5 mg/kg.h SAB starting at 20 min before or 20 min after TNF-a administration, respectively, The expressions of CDllb/CD18 and CD62L in leukocytes were measured with flow cytometry, Immunohistochemical staining was also used to detect E-selectin and ICAM-1 expression in endothelial cells, Results: Compared with craniotomy method, the bone-abrading method preserved a higher erythrocyte velocity in cerebral venules and more opening capillaries. TNF-a intervention only caused responses of vascular hyperpermeability and leukocyte roiling on venular walls, without leukocyte adhesion and other hemodynamic changes. Pre- or post-SAB treatment attenuated those responses and suppressed the enhanced expressions of CDII b/CDI8 and CD62L in leukocytes and E-selectin and ICAM-I in endothelial cells induced by TNF-a. Conclusions: The pre- and post-applications of SAB during TNF-a stimulation could suppress adhesive molecular expression and subsequently attenuate the increase of cerebral vascular permeability and leukocyte rolling.
基金supported by National Basic Research Program of China (2011CB935800)the Jilin Provincial Science and Technology Department (20100701)
文摘We report a functionalisation strategy which is able to generate Ricinus communis agglutinin 1 (RCA 120) modified PMMA microfluidic device for binding and culturing living cells. The functionalisation is achieved by standard aminealdehyde (Schiff base) reaction through the crosslinker, glutaraldehyde. To prove the ability of the RCA 120 modified PMMA surface, the PC 12 cell line (rat pheochromocytoma ceils) has been captured and cultured by the microfluidic device. In the presence of tunicamycin, the dose/timedependence on decreasing of binding affinity of RCA 120 modified device with PC 12 cell is also observed. The experimental results demonstrate that the lectin-functionalized microfluidic device can be employed as efficient cell culturing platform, and has a great promise of being used as a powerful tool for monitoring the interaction of drug with living cell.