Résumé
Objective To investigate the value of 18F-FDG,11C-MET and 11C-CHO PET/CT in the differentiation of C6 glioma from different kinds of inflammation in experimental rat models.Methods (1) A total of 48 male SD rats were randomly divided into 6 groups by the random number table:group 1 and 2 consisted of 8 rats bearing both C6 glioma and turpentine oil-induced acute inflammation;group 3 and 4 consisted of 8 rats bearing both C6 glioma and turpentine oil-induced chronic inflammation;group 5 and 6 consisted of 8 rats bearing both C6 glioma and BCG-induced granuloma.(2) 18F-FDG and 11C-MET PET/CT were performed on rats of group 1,3 and 5;18F-FDG and 11C-CHO PET/CT were performed on rats of group 2,4 and 6.The lesion-to-muscle ratios and tumor selectivity index (SI) were calculated.(3)After the PET/CT imaging,the lesions were excised.Immunohistochemical staining was used to demonstrate the situation of Glut-1,HIF-1α and CD98.(4)Two-sample t test,Nemenyi test and nonparametric Kruskal-Wallis H test were used for statistical analyses.Results (1) 18 F-FDG and 11 C-MET uptake in C6 glioma were higher than those in different inflammatory tissues(t--1.425-3.901,all P＜0.05).The 11 C-CHO uptake among different lesions were not significant (t =0.031-3.901,all P＞0.05).In group 1 and 5 models,SIMET(4.22±2.96 and 4.89±2.08) was significantly higher than SIFDG(1.77±0.86 and 1.72±0.77;t =2.717and 2.490,both P＜0.05);but iu group 3 models,SIMET(3.84±2.71) was not significantly higher than SIFDG(2.28± 1.14;t =2.082,P＞0.05).(2) Immunohistochemical study showed that there were significant differences in the expression of HIF-1 α,CD98 among different lesions (H =17.810,26.540,both P ＜ 0.05),and no significances of expression of Glut-1 among different lesions (H=5.940,P＞0.05).Nemenyi test showed that there was significant difference for CD98 expression between C6 glioma and acute inflammation,C6 glioma and granuloma (x2=5.504,9.345,both P＜O.05),and for HIF-1α and CD98 expression between C6 glioma and chronic inflammation (x2 =-5.938,2.128,both P＜0.05).Conclusions Compared with 18F-FDG and 11 C-CHO,11 C-MET has better tumor specificity.11 C-CHO PET/CT is not suitable for the differentiation of tumor and inflammation because of its lowest specificity.
Résumé
Objective Near-infrared (NIR) reflectance spectroscopy was used to develop a fast quality assessment method by simultaneous material identification and moisture quantification of Radix Ginseng Rubra (RGR). Methods The sample was identified by the comparison of its spectrum with a standard NIR spectral library. Similarity measurement was used as the discriminating parameter. The moisture content of sample was quantified by a partial least square (PLS) calibration model, correlative spectrum calculation was used for wavelength selection and multiplicative signal correction (MSC) was applied for pretreatment in the calibration model. Primary reference data were obtained using the traditional loss on drying (LOD) method. Results The NIR library can distinguish RGR from the counterfeit successfully. The optimized eight-factor PLS calibration model of NIR spectra has a high correlation coefficient (R=(0.999 7).) Conclusion The proposed method is rapid, accurate and can be used routinely in the traditional Chinese materia medica manufacturers for quality control of raw materials.