Breast cancer is a common malignant tumor.It is essential to develop suitable animal models for discovering novel preventive and therapeutic approaches.Tree shrews(Tupaia belangeri chinensis) have a closer evolution...Breast cancer is a common malignant tumor.It is essential to develop suitable animal models for discovering novel preventive and therapeutic approaches.Tree shrews(Tupaia belangeri chinensis) have a closer evolutionary relationship with humans than do rodents,which have been widely used in laboratory research.Spontaneous breast tumors were identified in tree shrews in 1960s;however,no detailed studies about tree shrew breast tumors have been conducted to date.Here,we characterized a spontaneous breast tumor from tree shrews by Haematoxylin Eosin(HE) staining.This tumor was identified as a papillary tumor.Immunohistochemical staining(IHC) for progesterone receptor(PR),Ki-67 and cleaved caspase-3 showed that tumor cells were positive for PR,highly proliferative,and less apoptotic compared to normal breast epithelial cells.Thus,the spontaneous tumor of tree shrew is very close to human papillary tumors in terms of morphology and pathology and we concluded that tree shrew may be a suitable animal model for breast cancer research.展开更多
Aim To prepare the prolonged-released microspheres of mefformin hydrochloride. Methods Ion-exchange resin-drug mefformin hydrochloride complexes were prepared as core materials, and followed by coating using ethylcell...Aim To prepare the prolonged-released microspheres of mefformin hydrochloride. Methods Ion-exchange resin-drug mefformin hydrochloride complexes were prepared as core materials, and followed by coating using ethylcellulose (EC) by the emulsion solvent diffusion technique. The release rate of mefformin from the microcapsules was highly dependent on the encapsulating formulation, thus being used as an index for formulation screening. Orthogonal experiments were performed to optimize the coating formulation. Results The final chosen formulation for coating of mefformin microcapsules were as follows: ( 1 ) the ratio of EC (20cps) to EC (45cps) was 50:50; (2) the ratio of plasticizer to coating materials was 20% ;and (3) the ratio of resin-mefformin complexes to coating materials was 5 : 1. Conclusion The prolonged release microspheres of mefformin hydrochloride were successfully prepared.展开更多
Aim To prepare a self-emulsifying microemulsion of 9-nitrocamptothecin (9-NC ME) for intravenous injection and investi- gation of its pharmacokinetic profiles in normal SD rats. Methods 9-NC ME was optimized in term...Aim To prepare a self-emulsifying microemulsion of 9-nitrocamptothecin (9-NC ME) for intravenous injection and investi- gation of its pharmacokinetic profiles in normal SD rats. Methods 9-NC ME was optimized in terms of droplet size and lack of drug precipitation following aqueous dilution using a pseudo-ternary phase diagram. Physicochemical properties of 9-NC ME were evaluated. 9-NC ME was intravenously administered via tail vein in healthy rats. Results A stable microemulsion was formulated consisted of soybean oil as oil phase, EPC/Tween-80 as emulsifier, and anhydrous ethanol as co-emulsifier. The droplets of the microemulsion were spherical shape with mean diameter of 38.3 ± 4.0 nm after 1:20 dilution with 5% glucose injection. The pharmacokinetic parameters of 9-NC ME after intravenous administration in rats were t1/2 of 0.97 ± 0.14 h, A UC0-8 of 372.77 ±49.62 ng·h·mL^-1 and MRT of 1.40 ± 0.21 h which were 1.4-fold, 1.65-fold, and 1.4-fold more than those of 9-NC solution (P〈0.01). Conclusion The results suggested that 9-NC ME was a promising drug delivery system and it was expected to provide a novel 9-NC injection for cancer patients.展开更多
Abundant microfibrillar protein inclusions were present in the lutoids of the primary laticifers in Hevea brasiliensis Mull. Arg. Two forms of the inclusions could be distinguished under the electron microscope, each ...Abundant microfibrillar protein inclusions were present in the lutoids of the primary laticifers in Hevea brasiliensis Mull. Arg. Two forms of the inclusions could be distinguished under the electron microscope, each in separate lutoids. As revealed by SDS-PAGE, the 59.5 kD and 63.5 kD proteins were the major components of the microfibrillar protein purified by isoeleettic point precipitation. Western-blotting analysis indicated that they were immunorelated with the 67 kD protein accumulated in the protein-storing cells. The 59.5 kD and 63.5 kD proteins were abundant in the uppermost part, the stem of new shoot and sustained their abundance during the growth and development of new shoot while their contents decreased remarkably in the lower parts of the trunk, accompanying by the accumulation of 3-5 kinds of proteins with low molecular weights. This fluctuating pattern suggested that the degradation of the 59.5 kD and 63.5 kD proteins had nothing to do with the new shoot growth and may be closely related to the primary laticifer differentiation. The 67 kD protein could not be detected in the young stem of new shoot when its leaves were broze-colored while the protein started to be accumulated in the stem, when the leaves of new shoot had matured, behaving like a typical vegetative storage protein.展开更多
In this study, the rubber tree clone PR107 was selected as test material,and its yields and physiological features under micro-tapping with different concentrations of ethylene were compared. The results showed that t...In this study, the rubber tree clone PR107 was selected as test material,and its yields and physiological features under micro-tapping with different concentrations of ethylene were compared. The results showed that there was no significant correlation between rubber yield and ethylene concentration applied by microtapping on PR107. Too high level of ethylene was not conducive to improvement of rubber yield. When the ethylene concentration for micro-tapping was higher than60%, physical deficiencies appeared in rubber tree PR107, the dry rubber content was reduced, and the yield was unstable. Instead, when the ethylene concentration was lower than 40%, the physiological features of PR107 were steady, the dry rubber content was stable, and the yield was relatively high.展开更多
The modified petroleum resin emulsion prepared from the C9petroleum resin was modified with maleic anhydride.The effects of maleic rosin and maleic anhydride addition level,the modification time and the alkali liquor ...The modified petroleum resin emulsion prepared from the C9petroleum resin was modified with maleic anhydride.The effects of maleic rosin and maleic anhydride addition level,the modification time and the alkali liquor on the properties of the emulsion were discussed.The results showed that the optimum process conditions covered:a maleic anhydride mass fraction of 1.5%,a maleic rosin mass fraction of 10%,a KOH mass fraction of 1%,a petroleum resin modification temperature of 200℃,a petroleum resin modification duration of 3 h,and a modified petroleum resin emulsion/wax emulsion mixing ratio of 1:1.The particle size of modified petroleum resin emulsion prepared under these conditions was equal to 104.166μm.展开更多
The uniform surface ion-imprinted resins for Zn2+ as the imprinting guest were prepared by emulsifier-free emulsion polymerization utilizing ally phenyl hydrogenphosphate as a functional comonomer. The Zn2+-imprinted ...The uniform surface ion-imprinted resins for Zn2+ as the imprinting guest were prepared by emulsifier-free emulsion polymerization utilizing ally phenyl hydrogenphosphate as a functional comonomer. The Zn2+-imprinted resin adsorbed Zn2+ much more effectively than did the unimprinted one. The selective feature of the surface imprinted resins to the template ions was demonstrated.展开更多
Taking into account the viscoelasticity of the fenugreek gum, a modified Maxwell model in terms of fractional derivatives is developed. Using this model, it is observed that the fenugreek gums with at least two differ...Taking into account the viscoelasticity of the fenugreek gum, a modified Maxwell model in terms of fractional derivatives is developed. Using this model, it is observed that the fenugreek gums with at least two different concentrations obey the Cox-Merz rule.展开更多
Removal of vegetal oil from wastewater using comercial resins in batch reactors processes is studied in present study. A traditional and patented type of three different surfactants was used for stabilizing of the emu...Removal of vegetal oil from wastewater using comercial resins in batch reactors processes is studied in present study. A traditional and patented type of three different surfactants was used for stabilizing of the emulsion phase. The results for the emulsion made by the synthesized surfactant showed much better stability and performance in the separation process compared to that by conventionally used Span 80. To determine the optimum operation conditions, the effect of several parameters such as initial oil concentration, amount of resin in the solid phase, adding or not a surfactant, resin type, and stabilizer concentration have been investigated. It was found that under the optimum conditions, more than 98% ofoil can be removed in a single batch process.展开更多
A silicone acrylate micro-emulsion of multipolymer was prepared by seed emulsion polymerization. The effects of polymerization process, emulsifier rate and amount, initiator rate and amount, polymerization temperature...A silicone acrylate micro-emulsion of multipolymer was prepared by seed emulsion polymerization. The effects of polymerization process, emulsifier rate and amount, initiator rate and amount, polymerization temperature, functional monomers, titration time on performances of emulsion have been discussed in detail.展开更多
Drug delivery by nanocarriers requires characterizations of suitable particle size, high drug loading and safety. In this work, we prepared an amphiphilic dendrimer modified PEG-PLA mixed nanoparticles(NPs) by a dou...Drug delivery by nanocarriers requires characterizations of suitable particle size, high drug loading and safety. In this work, we prepared an amphiphilic dendrimer modified PEG-PLA mixed nanoparticles(NPs) by a double emulsion-solvent evaporation(DESE) method. The particle size and drug encapsulation efficacy(EE) were compared to evaluate and optimize the preparation parameters. The mixed NPs had average size ranging from(102±1) nm to(137±5) nm, and the zeta potential turned to positive with incorporation of the amphiphilic dendrimer. The NPs showed different EE of docetaxel(DTX) and paclitaxel(PTX) with higher affinity to more lipophilic PTX. The blank mixed NPs showed little cytotoxicity, and the DTX-loaded NPs could effectively facilitate the antiproliferation activity on PC-3 cells. The NPs could be used as an effective drug delivery system, and its anti-tumor effect is worthy of further study.展开更多
基金Yunnan Province High-Profile Talent Project (2010CI114)the Chinese Academy of Sciences,Basic Frontier Project (KSCX2-EW-J-23)
文摘Breast cancer is a common malignant tumor.It is essential to develop suitable animal models for discovering novel preventive and therapeutic approaches.Tree shrews(Tupaia belangeri chinensis) have a closer evolutionary relationship with humans than do rodents,which have been widely used in laboratory research.Spontaneous breast tumors were identified in tree shrews in 1960s;however,no detailed studies about tree shrew breast tumors have been conducted to date.Here,we characterized a spontaneous breast tumor from tree shrews by Haematoxylin Eosin(HE) staining.This tumor was identified as a papillary tumor.Immunohistochemical staining(IHC) for progesterone receptor(PR),Ki-67 and cleaved caspase-3 showed that tumor cells were positive for PR,highly proliferative,and less apoptotic compared to normal breast epithelial cells.Thus,the spontaneous tumor of tree shrew is very close to human papillary tumors in terms of morphology and pathology and we concluded that tree shrew may be a suitable animal model for breast cancer research.
文摘Aim To prepare the prolonged-released microspheres of mefformin hydrochloride. Methods Ion-exchange resin-drug mefformin hydrochloride complexes were prepared as core materials, and followed by coating using ethylcellulose (EC) by the emulsion solvent diffusion technique. The release rate of mefformin from the microcapsules was highly dependent on the encapsulating formulation, thus being used as an index for formulation screening. Orthogonal experiments were performed to optimize the coating formulation. Results The final chosen formulation for coating of mefformin microcapsules were as follows: ( 1 ) the ratio of EC (20cps) to EC (45cps) was 50:50; (2) the ratio of plasticizer to coating materials was 20% ;and (3) the ratio of resin-mefformin complexes to coating materials was 5 : 1. Conclusion The prolonged release microspheres of mefformin hydrochloride were successfully prepared.
基金National Natural Science Foundation of China (GrantNo.30430760)the 985 projects (Phase II) of the State Key Labo-ratory of Natural and Biomimetic Drugs (Peking University, China).
文摘Aim To prepare a self-emulsifying microemulsion of 9-nitrocamptothecin (9-NC ME) for intravenous injection and investi- gation of its pharmacokinetic profiles in normal SD rats. Methods 9-NC ME was optimized in terms of droplet size and lack of drug precipitation following aqueous dilution using a pseudo-ternary phase diagram. Physicochemical properties of 9-NC ME were evaluated. 9-NC ME was intravenously administered via tail vein in healthy rats. Results A stable microemulsion was formulated consisted of soybean oil as oil phase, EPC/Tween-80 as emulsifier, and anhydrous ethanol as co-emulsifier. The droplets of the microemulsion were spherical shape with mean diameter of 38.3 ± 4.0 nm after 1:20 dilution with 5% glucose injection. The pharmacokinetic parameters of 9-NC ME after intravenous administration in rats were t1/2 of 0.97 ± 0.14 h, A UC0-8 of 372.77 ±49.62 ng·h·mL^-1 and MRT of 1.40 ± 0.21 h which were 1.4-fold, 1.65-fold, and 1.4-fold more than those of 9-NC solution (P〈0.01). Conclusion The results suggested that 9-NC ME was a promising drug delivery system and it was expected to provide a novel 9-NC injection for cancer patients.
文摘Abundant microfibrillar protein inclusions were present in the lutoids of the primary laticifers in Hevea brasiliensis Mull. Arg. Two forms of the inclusions could be distinguished under the electron microscope, each in separate lutoids. As revealed by SDS-PAGE, the 59.5 kD and 63.5 kD proteins were the major components of the microfibrillar protein purified by isoeleettic point precipitation. Western-blotting analysis indicated that they were immunorelated with the 67 kD protein accumulated in the protein-storing cells. The 59.5 kD and 63.5 kD proteins were abundant in the uppermost part, the stem of new shoot and sustained their abundance during the growth and development of new shoot while their contents decreased remarkably in the lower parts of the trunk, accompanying by the accumulation of 3-5 kinds of proteins with low molecular weights. This fluctuating pattern suggested that the degradation of the 59.5 kD and 63.5 kD proteins had nothing to do with the new shoot growth and may be closely related to the primary laticifer differentiation. The 67 kD protein could not be detected in the young stem of new shoot when its leaves were broze-colored while the protein started to be accumulated in the stem, when the leaves of new shoot had matured, behaving like a typical vegetative storage protein.
基金Supported by Project of National Natural Rubber Industry Technology System of China(CARS-34-GW7)Project of Agricultural Technology Extension and System Construction for Tropical Crops(13RZNJ-43)Fundamental Research Funds of Rubber Research Institute,Chinese Academy of Tropical Agricultural Sciences(1630022013023)~~
文摘In this study, the rubber tree clone PR107 was selected as test material,and its yields and physiological features under micro-tapping with different concentrations of ethylene were compared. The results showed that there was no significant correlation between rubber yield and ethylene concentration applied by microtapping on PR107. Too high level of ethylene was not conducive to improvement of rubber yield. When the ethylene concentration for micro-tapping was higher than60%, physical deficiencies appeared in rubber tree PR107, the dry rubber content was reduced, and the yield was unstable. Instead, when the ethylene concentration was lower than 40%, the physiological features of PR107 were steady, the dry rubber content was stable, and the yield was relatively high.
文摘The modified petroleum resin emulsion prepared from the C9petroleum resin was modified with maleic anhydride.The effects of maleic rosin and maleic anhydride addition level,the modification time and the alkali liquor on the properties of the emulsion were discussed.The results showed that the optimum process conditions covered:a maleic anhydride mass fraction of 1.5%,a maleic rosin mass fraction of 10%,a KOH mass fraction of 1%,a petroleum resin modification temperature of 200℃,a petroleum resin modification duration of 3 h,and a modified petroleum resin emulsion/wax emulsion mixing ratio of 1:1.The particle size of modified petroleum resin emulsion prepared under these conditions was equal to 104.166μm.
基金Financial supported by the Natural Science Foundation of China (No: 50003006)
文摘The uniform surface ion-imprinted resins for Zn2+ as the imprinting guest were prepared by emulsifier-free emulsion polymerization utilizing ally phenyl hydrogenphosphate as a functional comonomer. The Zn2+-imprinted resin adsorbed Zn2+ much more effectively than did the unimprinted one. The selective feature of the surface imprinted resins to the template ions was demonstrated.
基金Supported by the National Natural Science Foundation of China(No.29576238).
文摘Taking into account the viscoelasticity of the fenugreek gum, a modified Maxwell model in terms of fractional derivatives is developed. Using this model, it is observed that the fenugreek gums with at least two different concentrations obey the Cox-Merz rule.
文摘Removal of vegetal oil from wastewater using comercial resins in batch reactors processes is studied in present study. A traditional and patented type of three different surfactants was used for stabilizing of the emulsion phase. The results for the emulsion made by the synthesized surfactant showed much better stability and performance in the separation process compared to that by conventionally used Span 80. To determine the optimum operation conditions, the effect of several parameters such as initial oil concentration, amount of resin in the solid phase, adding or not a surfactant, resin type, and stabilizer concentration have been investigated. It was found that under the optimum conditions, more than 98% ofoil can be removed in a single batch process.
基金Ministry of Science and Technology of China for Major State Basic Research Projects (2002AA322020)
文摘A silicone acrylate micro-emulsion of multipolymer was prepared by seed emulsion polymerization. The effects of polymerization process, emulsifier rate and amount, initiator rate and amount, polymerization temperature, functional monomers, titration time on performances of emulsion have been discussed in detail.
基金National Natural Science Foundation of China(Grant No.81473156,81673365,81273454)Doctoral Foundation of the Ministry of Education(Grant No.20130001110055)National Key Basic Research Program(Grant No.2013CB932501)
文摘Drug delivery by nanocarriers requires characterizations of suitable particle size, high drug loading and safety. In this work, we prepared an amphiphilic dendrimer modified PEG-PLA mixed nanoparticles(NPs) by a double emulsion-solvent evaporation(DESE) method. The particle size and drug encapsulation efficacy(EE) were compared to evaluate and optimize the preparation parameters. The mixed NPs had average size ranging from(102±1) nm to(137±5) nm, and the zeta potential turned to positive with incorporation of the amphiphilic dendrimer. The NPs showed different EE of docetaxel(DTX) and paclitaxel(PTX) with higher affinity to more lipophilic PTX. The blank mixed NPs showed little cytotoxicity, and the DTX-loaded NPs could effectively facilitate the antiproliferation activity on PC-3 cells. The NPs could be used as an effective drug delivery system, and its anti-tumor effect is worthy of further study.