RESUMO
In recent years, near-infrared spectroscopy has developed into an analytical technique widely used in various fields. Because of its advantages of fast, green and non-destructive, it plays an increasingly prominent role in the field of traditional Chinese medicine (TCM) analysis. However, due to the complexity and overlap of spectra, near-infrared spectroscopy needs to be combined with chemometrics for analysis and calculation. The principle, application scope, advantages and limitations of near infrared spectroscopy and chemometrics are summarized in detail, in addition, their combined applications in the identification of the origin, authenticity, processed products, composition prediction and water content detection of TCM are reviewed. The authors discussed and analyzed the joint application of near-infrared spectroscopy and chemometrics in the field of TCM analysis, and summarized the unique advantages of the combined technology in the field of TCM, which had certain guiding significance for medical workers to better use this technology.
RESUMO
<p><b>OBJECTIVE</b>To study the effect of dihydroartemisinin (DHA) combined irradiation on the apoptosis of human lung cancer GLC-82 cells and to study its mechanism.</p><p><b>METHODS</b>The growth inhibition rate of GLC-82 cells acted by different concentrations DHA was detected using MTT assay at 24, 48, and 72 h, respectively. Clone forming test was used. With multi-target single-hit model, the radiosensitization effect was assessed by calculating sensitizing enhancement ratio (SER).The effect of DHA combined irradiation on the apoptosis of GLC-82 cell cycle distribution and apoptosis were measured by flow cytometry. The protein expression of p53, p21, Bcl-2, and Bax were detected by Western blot.</p><p><b>RESULTS</b>Different concentrations DHA (4, 8, 16, 32, 64, and 128 μg/mL) had cytotoxicity on GLC-82 cells. The IC50 for 24, 48, and 72 h was 38.25,20.58, and 10.36 μg/mL, respectively, in obvious dose- and time-dependent manner. The growth inhibition rate was more significantly increased than that of the blank control group (P < 0.01, P<0.05). DHA had sensitization enhancement effect on GLC-82 cells, with SER of 1.4. DHA combined irradiation could obviously change the structure of GLC-82 cells cell cycle and induce apoptosis (with the apoptosis rate of 21.5%), which was significantly different from that of the blank control group (P < 0.05). Western blot showed the expression of p53 and p21 protein could be increased by DHA combined irradiation, and the expression of Bcl-2 protein down-regulated (P <0.01, P <0. 05).</p><p><b>CONCLUSIONS</b>DHA had stronger cytotoxicity and radiosensitization on GLC-82 cells. Its mechanisms might lie in making the arrest of GLC-82 cells' growth at G0/G1 phase, decreasing the ratio of cells at S phase, restoring the function of p53, decreasing the expression of Bcl-2 protein, and inducing apoptosis in GLC-82 cells.</p>