AIM:To investigate the antioxidant activity of chitooligosaccharides(COSs)on pancreatic islet cells in diabetic rats induced by streptozotocin. METHODS:The antioxidant effect of COSs on pancreatic islet cells was dete...AIM:To investigate the antioxidant activity of chitooligosaccharides(COSs)on pancreatic islet cells in diabetic rats induced by streptozotocin. METHODS:The antioxidant effect of COSs on pancreatic islet cells was detected under optical microscopy and with colorimetric assay and gel electrophoresis.The activities of glutathione peroxidase and superoxide dismutase,total antioxidant capacity,and content of malondialdehyde in serum and tissue slices of pancreas were examined after 60 d to determine the effect of COSs in streptozotocin-induced diabetes in rats. RESULTS:COSs can prohibit the apoptosis of pancreatic islet cells.All concentrations of COSs can improve the capability of total antioxidant capacity and activity of superoxide dismutase and decrease the content of malondialdehyde drastically.Morphological investigation in the pancreas showed that COSs have resulted in the reduction of islets,loss of pancreatic cells,and nuclear pyknosis of pancreatic cells. CONCLUSION:COSs possess various biological activities and can be used in the treatment of diabetes mellitus.展开更多
To investigate sulfide detoxification in Urechis unicinctus,oxygen consumption rate and sulfide detoxification productswere analyzed during sulfide exposure under controlled laboratory conditions.The results showed th...To investigate sulfide detoxification in Urechis unicinctus,oxygen consumption rate and sulfide detoxification productswere analyzed during sulfide exposure under controlled laboratory conditions.The results showed that oxygen consumption rateswere elevated significantly during 3 h sulfide exposure compared to the control(P<0.05).The concentration of sulfite in body walland hindgut of experimental worms increased significantly(P<0.05)when exposed to 50μmolL-1sulfide,reached a maximum at24 h and then decreased.Similar result was observed in worms exposed to 150μmolL-1sulfide except that sulfite concentrationreached a maximum at 12 h.Contents of thiosulfate in body wall and hindgut of U.unicinctus exposed to sulfide were also significantly higher than that of the control without sulfide exposure.In conclusion,during short-time sulfide exposure U.unicinctus mayraise oxygen consumption to detoxify toxic sulfide into sulfite and thiosulfate.Sulfide detoxification was restrained when the expo-sure time was prolonged or sulfide concentration was increased,which was indicated by decrease of sulfite,the intermediate productof sulfide detoxification.展开更多
Phytochemical investigation of the aerial parts of Euphorbia sikkimensis led to the isolation of one new diterpenoids,named sikkimenoid E(1),together with thirteen other known compounds(2-14).Their structures were est...Phytochemical investigation of the aerial parts of Euphorbia sikkimensis led to the isolation of one new diterpenoids,named sikkimenoid E(1),together with thirteen other known compounds(2-14).Their structures were established by means of spectroscopic methods.Compound 2 was identified to be a trinortriterpenoid,and derived for the first time from a natural source.In this paper we reveal for the first time its comprehensive spectral data and NMR spectral assignment.Compound 4 showed anti-angiogenic activity with an IC_(50) value of 5.66μM in a zebrafish model,and compounds 5 and 6 exhibited cytotoxicity toward A549 cell line with IC_(50) values of 12.12 and 6.45μM,respectively.展开更多
Three new minor prenylated flavonoids,named macadenanthins A–C(1–3),together with three known ones(4–6),were isolated from the twigs of Macaranga adenantha.Their structures were elucidated on the basis of extensive...Three new minor prenylated flavonoids,named macadenanthins A–C(1–3),together with three known ones(4–6),were isolated from the twigs of Macaranga adenantha.Their structures were elucidated on the basis of extensive spectroscopic analysis including NMR,UV and MS.The prenyl moieties in compounds 1–3 were further modified by cyclization and hydroxylation.The new compounds were tested for their cytotoxicity against four cancer cell lines(MCF-7,Hep G2,Hela and P388)and showed IC50 values in the range of 13.76–22.27 lM.展开更多
Four novel gemini quaternary ammonium surfactants containing DSD acid-triazine structure were synthesized using a facile three-step synthetic route , from 4,4'-diamino-2,2'-disulfonic-stilbene (DSD acid), cyan...Four novel gemini quaternary ammonium surfactants containing DSD acid-triazine structure were synthesized using a facile three-step synthetic route , from 4,4'-diamino-2,2'-disulfonic-stilbene (DSD acid), cyanuric chloride and dimethyl dodecylamine. The structures and optical properties of compounds (6a-d) were characterized by Fourier-Transform infrared (FT-IR) spectroscopy, UV-visible absorption spectra and fluorescence emission spectrum. The surface tension and the Critical Micelle Concentration (CMC) were evaluated. The result shows that the four compounds at lower concentrations can greatly reduce the surface tension of aqueous solutions. The spectroscopic properties of? these quaternary ammonium salts are assessed for their effectiveness and potential as fluorescent brightening agents.展开更多
The sensing sensitivity of the wavelength interrogated surface plasmon resonance(WISPR) biosensor could be improved by self-assembly of nanoporous thin-film of TiO2 nanoparticles/DNA(TiO2/DNA)n(n is the number of...The sensing sensitivity of the wavelength interrogated surface plasmon resonance(WISPR) biosensor could be improved by self-assembly of nanoporous thin-film of TiO2 nanoparticles/DNA(TiO2/DNA)n(n is the number of bilayer) on wavelength interrogated surface plasmon resonance(WISPR) chips.The growth behavior and surface structure of the nanoporous thin-film were investigated by UV-Vis spectroscopy and scanning electron microscopy,respectively.The home-made WISPR sensor with Krestchmann configuration consisted of a tungsten-halogen lamp as a photon source and a CCD camera as the detector.After the deposition of (DNA/TiO2)n thin film on WISPR chips,the resonance peak of the reflection spectra appeared in air.With the increases of n,the resonance wavelength gradually red shifted,which is consistent with the simulated results.After the optimization of the porous film,the WISPR biosensor was utilized to detect low-molecular-weight analytes,such as biotin.The result demonstrates that the sensitivity of [poly(styrene sulfonate)/polyally lamine hydrochlorides]5(PSS/PAH)5 could be 4 times higher than that of polyelectrolyte multilayer modified WISPR sensor.展开更多
Two new minor constituents,musinisins A(1)and B(2),together with five known compounds(3-7),were isolated from the aerial parts of Munronia sinica.Their structures were established by means of spectroscopic methods and...Two new minor constituents,musinisins A(1)and B(2),together with five known compounds(3-7),were isolated from the aerial parts of Munronia sinica.Their structures were established by means of spectroscopic methods and the absolute stereochemistry of 1 was determined by single crystal X-ray experiment.Compound 4 showed antiangiogenic activity evaluated by a zebrafish model and apoptosis-inducing effect on A549 lung cancer cells.展开更多
The sensing sensitivity of wavelength interrogated surface plasmon resonance(WISPR) biosensor is improved by self-assembly of polyelectrolyte multilayer(PEM) film of poly(allylamine hydrochloride)(PAH)/ poly(...The sensing sensitivity of wavelength interrogated surface plasmon resonance(WISPR) biosensor is improved by self-assembly of polyelectrolyte multilayer(PEM) film of poly(allylamine hydrochloride)(PAH)/ poly(sodium-p-styrenesulfonate)(PSS) on the Au film coated glass chip via the layer-by-layer(LBL) technique. The home-made WISPR with Krestchmann configuration consists of a tungsten-halogen lamp as a photon source and a charge coupled device(CCD) camera as the detector. The influence of PEM film thickness on the optical properties of WISPR biosensors was investigated theoretically and experimentally. In order to achieve higher sensing sensitivity, the PEM film thickness has to be designed as ca.14 nm at an Au layer thickness of 50 nm and an incidental angle of 11.8°. Furthermore, the PEM coated WISPR biosensor can serve as highly sensitive biosensor, in which the biotin-streptavidin is used as bioconjugate pair. After deposition of the PEM film of (biotin/PAH)(PSS/PAH)3, the modified WISPR biosensor is more sensitive to the low concentration(〈0.01 mg/mL) of streptavidin. And the sensing sensitivity can be further increased by one order of magnitude compared with that of the biotin/PAH coated WISPR biosensor. Thus, such low-cost, high-performance and efficient PEM-coated WISPR biosensors have great potentials in a diverse array of fields such as medical diagnostics, drug screening, food safety analysis, environmental monitoring, and homeland security.展开更多
基金Supported by The National Scientific Research Fund of China(2008JK007)the National Key Research and Development Program of China for the Tenth Five-Year Plan,No.2006BAD06A14
文摘AIM:To investigate the antioxidant activity of chitooligosaccharides(COSs)on pancreatic islet cells in diabetic rats induced by streptozotocin. METHODS:The antioxidant effect of COSs on pancreatic islet cells was detected under optical microscopy and with colorimetric assay and gel electrophoresis.The activities of glutathione peroxidase and superoxide dismutase,total antioxidant capacity,and content of malondialdehyde in serum and tissue slices of pancreas were examined after 60 d to determine the effect of COSs in streptozotocin-induced diabetes in rats. RESULTS:COSs can prohibit the apoptosis of pancreatic islet cells.All concentrations of COSs can improve the capability of total antioxidant capacity and activity of superoxide dismutase and decrease the content of malondialdehyde drastically.Morphological investigation in the pancreas showed that COSs have resulted in the reduction of islets,loss of pancreatic cells,and nuclear pyknosis of pancreatic cells. CONCLUSION:COSs possess various biological activities and can be used in the treatment of diabetes mellitus.
基金supported by the National Natural Science Foundation of China under contract Nos.40776074and 30570223
文摘To investigate sulfide detoxification in Urechis unicinctus,oxygen consumption rate and sulfide detoxification productswere analyzed during sulfide exposure under controlled laboratory conditions.The results showed that oxygen consumption rateswere elevated significantly during 3 h sulfide exposure compared to the control(P<0.05).The concentration of sulfite in body walland hindgut of experimental worms increased significantly(P<0.05)when exposed to 50μmolL-1sulfide,reached a maximum at24 h and then decreased.Similar result was observed in worms exposed to 150μmolL-1sulfide except that sulfite concentrationreached a maximum at 12 h.Contents of thiosulfate in body wall and hindgut of U.unicinctus exposed to sulfide were also significantly higher than that of the control without sulfide exposure.In conclusion,during short-time sulfide exposure U.unicinctus mayraise oxygen consumption to detoxify toxic sulfide into sulfite and thiosulfate.Sulfide detoxification was restrained when the expo-sure time was prolonged or sulfide concentration was increased,which was indicated by decrease of sulfite,the intermediate productof sulfide detoxification.
基金This work was supported by the Basic Research Project of the Ministry of Science and Technology of China(2012FY110300)MOST grant(2008BAD98B06).
文摘Phytochemical investigation of the aerial parts of Euphorbia sikkimensis led to the isolation of one new diterpenoids,named sikkimenoid E(1),together with thirteen other known compounds(2-14).Their structures were established by means of spectroscopic methods.Compound 2 was identified to be a trinortriterpenoid,and derived for the first time from a natural source.In this paper we reveal for the first time its comprehensive spectral data and NMR spectral assignment.Compound 4 showed anti-angiogenic activity with an IC_(50) value of 5.66μM in a zebrafish model,and compounds 5 and 6 exhibited cytotoxicity toward A549 cell line with IC_(50) values of 12.12 and 6.45μM,respectively.
基金National Natural Science Foundation of China(31300293 and 81422046)General Project of Applied Foundation Research,Yunnan Province(2013FB067)+1 种基金Basic Research Project of Ministry of Science and Technology of China(2012FY110300)Major State Basic Research Development Program(2010CB951704).
文摘Three new minor prenylated flavonoids,named macadenanthins A–C(1–3),together with three known ones(4–6),were isolated from the twigs of Macaranga adenantha.Their structures were elucidated on the basis of extensive spectroscopic analysis including NMR,UV and MS.The prenyl moieties in compounds 1–3 were further modified by cyclization and hydroxylation.The new compounds were tested for their cytotoxicity against four cancer cell lines(MCF-7,Hep G2,Hela and P388)and showed IC50 values in the range of 13.76–22.27 lM.
文摘Four novel gemini quaternary ammonium surfactants containing DSD acid-triazine structure were synthesized using a facile three-step synthetic route , from 4,4'-diamino-2,2'-disulfonic-stilbene (DSD acid), cyanuric chloride and dimethyl dodecylamine. The structures and optical properties of compounds (6a-d) were characterized by Fourier-Transform infrared (FT-IR) spectroscopy, UV-visible absorption spectra and fluorescence emission spectrum. The surface tension and the Critical Micelle Concentration (CMC) were evaluated. The result shows that the four compounds at lower concentrations can greatly reduce the surface tension of aqueous solutions. The spectroscopic properties of? these quaternary ammonium salts are assessed for their effectiveness and potential as fluorescent brightening agents.
基金Supported by the National Natural Science Foundation of China(Nos.91123029, 61077066, 61340032), the National High Technology Research and Development Program of China(No.2012AA063302) and the Natural Science Foundation of Shandong Province, China(No.ZR2012CM029).
文摘The sensing sensitivity of the wavelength interrogated surface plasmon resonance(WISPR) biosensor could be improved by self-assembly of nanoporous thin-film of TiO2 nanoparticles/DNA(TiO2/DNA)n(n is the number of bilayer) on wavelength interrogated surface plasmon resonance(WISPR) chips.The growth behavior and surface structure of the nanoporous thin-film were investigated by UV-Vis spectroscopy and scanning electron microscopy,respectively.The home-made WISPR sensor with Krestchmann configuration consisted of a tungsten-halogen lamp as a photon source and a CCD camera as the detector.After the deposition of (DNA/TiO2)n thin film on WISPR chips,the resonance peak of the reflection spectra appeared in air.With the increases of n,the resonance wavelength gradually red shifted,which is consistent with the simulated results.After the optimization of the porous film,the WISPR biosensor was utilized to detect low-molecular-weight analytes,such as biotin.The result demonstrates that the sensitivity of [poly(styrene sulfonate)/polyally lamine hydrochlorides]5(PSS/PAH)5 could be 4 times higher than that of polyelectrolyte multilayer modified WISPR sensor.
基金supported financially by the Bureau of Science and Technology of Kunming City.
文摘Two new minor constituents,musinisins A(1)and B(2),together with five known compounds(3-7),were isolated from the aerial parts of Munronia sinica.Their structures were established by means of spectroscopic methods and the absolute stereochemistry of 1 was determined by single crystal X-ray experiment.Compound 4 showed antiangiogenic activity evaluated by a zebrafish model and apoptosis-inducing effect on A549 lung cancer cells.
基金Supported by the National High Technology Research and Development Program of China(No.2012AA063302), the National Natural Science Foundation of China(Nos.91123029, 61077066) and the Natural Science Foundation of Shandong Province, China(Nos.ZR2011FQ025, ZR2012CM029).
文摘The sensing sensitivity of wavelength interrogated surface plasmon resonance(WISPR) biosensor is improved by self-assembly of polyelectrolyte multilayer(PEM) film of poly(allylamine hydrochloride)(PAH)/ poly(sodium-p-styrenesulfonate)(PSS) on the Au film coated glass chip via the layer-by-layer(LBL) technique. The home-made WISPR with Krestchmann configuration consists of a tungsten-halogen lamp as a photon source and a charge coupled device(CCD) camera as the detector. The influence of PEM film thickness on the optical properties of WISPR biosensors was investigated theoretically and experimentally. In order to achieve higher sensing sensitivity, the PEM film thickness has to be designed as ca.14 nm at an Au layer thickness of 50 nm and an incidental angle of 11.8°. Furthermore, the PEM coated WISPR biosensor can serve as highly sensitive biosensor, in which the biotin-streptavidin is used as bioconjugate pair. After deposition of the PEM film of (biotin/PAH)(PSS/PAH)3, the modified WISPR biosensor is more sensitive to the low concentration(〈0.01 mg/mL) of streptavidin. And the sensing sensitivity can be further increased by one order of magnitude compared with that of the biotin/PAH coated WISPR biosensor. Thus, such low-cost, high-performance and efficient PEM-coated WISPR biosensors have great potentials in a diverse array of fields such as medical diagnostics, drug screening, food safety analysis, environmental monitoring, and homeland security.