Objective To evaluate the quality of the portal images acquired by computed radiography(CR)system and conventional screen-film system,respectively.Methods imaging plates (IP)and X-ray films of a home-devised lead phantom with a leakage of 6.45% were acquired,and modulation transfer function(MTF)curves of the both images were measured using edge method.Portal images of 40 nasopharyngeal cancer patients were acquired by IP and screen-film system respectively.Two doctors with similar experience evaluated the damage degree of petrosa] bone,the receiver operating characteristic(ROC)curve of CR images and general images were drawn according to two doctors evaluation results.Results The identification frequency of CR system and screen-film system were 1.159 and 0.806 Lp/mm respectively.For doctor one,the area under ROC curve of CR images and general images were 0.802 and 0.742 respectively.For doctor two,the area under ROC curve of CR images and general images were 0.751 and 0.600 respectively.The MTF curve and ROC curve of CR are both better than those of screen-film system.Conclusion The image quality of CR portal imaging is much better than that of screen-film system.The utility of CR in linear accelerator for portal imaging is promising in clinic.

Carbon source plays an important role in the constitutive expression of foreign proteins in Pichia pastoris. In present study, glucose , glycerol , methanol and oil acid, was used respectively as the only carbon source to constitutively express hAS in Pichia pastoris GS115 (pGAP9K-AS)in shaking flask. The result shows that oleic acid is the best (163 mg/L) compared with glycerol (83mg/L), glucose (76 mg/L)and methanol (57 mg/L). Since oleic acid is insoluble in water, glycerol was used as the carbon source in the high-density cell culture of GS115 (pGAP9K-AS) in a 30 liter bioreactor and 169 mg/L of angiostatin was obtained after 48h of culture. The expressed angiostatin is immunologically active as shown by Western blotting. The recombinant hAS inhibits bFGF induced CAM angiogenesis and suppresses the growth of B16 melanoma in C57BL/6J mice. The tumor inhibition rate is 90% after 12 days of treatment. Statistics analysis revealed that the tumor volume difference of mice between the hAS group and PBS group is prominent (P < 0.01).
Angiogenesis Inhibitors ; biosynthesis ; genetics ; therapeutic use ; Angiostatins ; biosynthesis ; genetics ; therapeutic use ; Animals ; Bioreactors ; microbiology ; Culture Media ; pharmacology ; Fermentation ; Glycerol ; pharmacology ; Humans ; Melanoma, Experimental ; drug therapy ; Mice ; Mice, Inbred C57BL ; Pichia ; genetics ; growth & development ; metabolism ; Recombinant Proteins ; biosynthesis ; genetics ; therapeutic use

OBJECTIVETo evaluate the effects of sodium arsenite on the activity, the mRNA and the protein expression of CAT in human keratinocyte cell line (HaCaT).

METHODSThe activity of catalase (CAT) was detected by ultraviolet direct velocity assay. RT-PCR was used to detect the mRNA expression of CAT and Western blotting was conducted to detect the protein expression of CAT.

RESULTSIf the cells were treated with higher than 5.0 micromol/L sodium arsenite, the activity, mRNA and protein expression of CAT were decreased significantly and in a dosage dependent fashion (P < 0.05).

CONCLUSIONCAT is inhibited by sodium arsenite in the transcription, translation and activity levels.

Arsenites ; toxicity ; Blotting, Western ; Catalase ; biosynthesis ; genetics ; Cell Line ; Dose-Response Relationship, Drug ; Humans ; Keratinocytes ; drug effects ; enzymology ; RNA, Messenger ; genetics ; Reverse Transcriptase Polymerase Chain Reaction ; Sodium Compounds ; toxicity

BACKGROUND: Activation of CD40 pathway negatively regulates the therapeutic effect of endothelial progenitor cells (EPCs), while inhibition of this pathway can enhance the biological function of the cells. OBJECTIVE: To compare the therapeutic effects of CD40-silenced EPCs (EPCs shRNA-CD40) and conventional EPCs transplantation in an animal model of pulmonary hypertension, and to explore the interventional effect of astragalosides on EPCs transplantation in the treatment of pulmonary hypertension. METHODS: Ninety SD rats were randomly divided into five groups: normal control group (n=24), model group (n=24), lentivirus transfection group (n=18), conventional transplantation group (n=18) and astragaloside group (n=6). Except the normal control group, the remaining four groups were given monocrotaline to induce pulmonary hypertension. Rats in the lentivirus transfection and conventional transplantation groups were given intravenous injection of Lv-shRNA-CD40-transfected EPCs and conventional EPCs respectively at 7, 14, 21 days after modeling (n=6 at each time point). Rats in the astragaloside group were given daily intraperitoneal injection of 80 mg/(kg?d) astragaloside within 1-21 days after modeling, and then Lv-shRNA-CD40-transfected EPCs were intravenously injected at 21 days after modeling. Hemodynamics, plasma endothelin-1 level and right ventricular hypertrophy index were detected at 28 days after modeling. RESULTS AND CONCLUSION: (1) After modeling, right ventricular pressure, mean pulmonary arterial pressure and right ventricular hypertrophy index were all increased compared with the normal control group (P < 0.05), while these indices were then decreased significantly after EPCs transplantation (P < 0.05). With the increasing of transplantation time, there was an increasing trend in the right ventricular pressure, mean pulmonary arterial pressure and right ventricular hypertrophy index in the two EPCs transplantation groups, but this trend was not remarkable in the lentivirus transfection group. (2) After modeling, the level of endothelin-1 was increased significantly compared with the normal control group (P < 0.05), and then decreased after EPCs transplantation (P < 0.05). The level of endothelin-1 in the lentivirus transfection group was significantly lower than that in the conventional transplantation group at the same time point (P < 0.05). (3) A significant improvement in hemodynamics, plasma endothelin-1 level and right ventricular hypertrophy index was observed in the astragaloside group as compared with the lentivirus transfection group (P < 0.05). Given the above findings, CD40-silenced EPCs transplantation is more effective and durable than the conventional transplantation in the treatment of pulmonary hypertension, and moreover, astragaloside can enhance the therapeutic effect.

In order to study the interaction between Pterocephalus hookeri and bitter taste receptors,three-dimensional structural models of bitter taste receptors TAS2 R16,TAS2 R14 and TAS2 R13 were established by homology modeling in this paper. Maestro software was used for docking the chemical constituents of P. hookeri with bitter taste receptors. The results showed that 25 chemical components of P. hookeri can regulate three bitter taste receptors. And these components were mainly iridoid glycosides and phenolic acids.This research focused on the comprehensive application of homology modeling and molecular docking technology to explore the interaction between bitter chemical constituents of P. hookeri and bitter taste receptors. This study provided assistance in revealing pharmacodynamic basis of bitter Tibetan medicine at molecular level. It also provided new ideas and methods for the study of Tibetan medicine.
Caprifoliaceae ; chemistry ; Correlation of Data ; Humans ; Medicine, Tibetan Traditional ; Molecular Docking Simulation ; Receptors, G-Protein-Coupled ; metabolism ; Taste