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The effects of canopy development, solar angle, and weather conditions on temporal variation in photosynthetic photon flux density(PPFD) at three heights within a tropical rain forest canopy in Xishuangbanna, China, were examined. PPFD was measured every second and stored as 10-min averages from 1 December 2002 to 30 November 2003. PPFD variability was examined at three different temporal scales. Specific days in March, September, and December with clear and overcast sky conditions were selected to separate the effects of leaf area index (LAI) and solar angle on diurnal variability. On both clear and overcast days, mean daily average PPFD was significantly different between March and September at all heights, except 10 m on clear days, suggesting that LAI directly influences PPFD. In contrast, the differences in daily average PPFD among three heights between September and December were likely due to variation in solar angle. In addition, daily average PPFD at all locations were significantly lower under overcast than clear sky conditions in March, September and December. Over the year-long study, the mean daily total PPFD at 21 m, 10 m and 4 m was 2.8, 2.7 and 0.7 mol/(m2 · d), which accounted for 9.7%, 9.4% and 2.4% of the daily PPFD above the canopy, respectively. Significant differences in mean daily total PPFD occurred at the same heights among different seasons, and diurnal, day-to-day and seasonal PPFD varied at different heights within the canopy. The possible effects of light variability on physiological and morphological responses of plants are discussed. [ABSTRACT FROM AUTHOR]

To compare the therapeutic effects of different treatment methods on the nude mice bearing colon cancer HT29 cells. BalB/C nude mice colon cancer stem cell models were established and randomly divided into the following four groups, with 8 nude mice in each group: blank control group, DC-CIK group, Huaier group, and Huaier combined with DC-CIK group (combined treatment group). The mice in DC-CIK group and combined treatment group received 1×10⁶ DC-CIK cells treatment by tail vein injectionafter the tumor stem cells were inoculated for 4 days,2 times a week for three weeks. The mice in Huaier group and combined treatment group received intragastric administration at the dose of 20 g/60 kg body weight, 0.2 mL/time, once a day for a total of three weeks. The mice in control group received equal volume of normal saline. Tumor size and body weight of nude mice were measured every 2 days during treatment for three weeks in each group. After the treatment, the nude mice were sacrificed to measure the tumor weight and the tumor inhibition rate was calculated. The RT-PCR method was used to detect the expression levels of the key genes in the signal pathway. After the end of the treatment, the quality of the tumor in the Huaier group, DC-CIK group and combined treatment group was significantly lower than that in the control group; the quality in combined treatment group was significantly lower than that in Huaier group and DC-CIK group.Among them, the tumor inhibition rate reached 46.77% in the combined treatment group. In respect of changes in expression levels of key genes in the signaling pathway, the mRNA expression levels of key genes PI3KR1 and Akt in PI3K/Akt pathway, key genes Wnt1 and CTTNB1 in Wnt/ β -catenin pathway, and key genes Notch1, Notch2, Notch3 in Notch pathway in the combined treatment group were lower than those in DC-CIK group and Huaier group. The Huaier combined with DC-CIK group showed best therapeutic effect among different treatment methods for HT29 stemcell colon tumors in nude mice, providing a new idea for clinical treatment of colon cancer., Competing Interests: The authors of this article and the planning committee members and staff have no relevant financial relationships with commercial interests to disclose., (Copyright© by the Chinese Pharmaceutical Association.)

Objective: To compare the effects and safety of immunotherapy using different methods to load DC-CIK cells for MDA-MB-231 breast cancer stem cells., Methods: A breast cancer model was established in BALB/c nude mice using breast cancer stem cells. All mice were randomly divided into six groups, and each group had three nude mice: the blank control group, the DC-CIK group (group D), the MDA-MB-231 CSC whole-cell lysate DC-CIK group (group L-D), the MDA-MB-231 CSC RNA DC-CIK group (group R-D), the THP DC-CIK group (group T-D) and group THP. Nude mice in groups D, L-D, R-D and T-D were injected with CSCs; 4 days later, the mice were inoculated with 1 × 10(6) DC-CIK cells via the tail vein. This injection was repeated 2 times a week for three weeks. The mice in groups THP and T-D were injected with a 5 mg/Kg dose of THP chemotherapeutic agents via the tail vein the day before DC-CIK injection, which was repeated one time a week for three weeks. Nude mice in the blank control group were injected with normal saline. The weights and sizes of the tumors were measured after the mice were euthanized. The expression of c-Myc, a key proto-oncogene associated with the Akt signaling pathway, was detected with RT-PCR., Results: The tumor growth rates in each group were as follows: group L-D < group R-D < group D < group T-D < blank control group < group THP. The nude mice in groups L-D, R-D and D were normal, active and had a healthy appetite. The mice in groups T-D and THP were lethargic, less active and showed loss of appetite, and their caudal vein was easy to stimulate. The mice in the blank control group were sacrificed during the third week or when their tumors developed ulceration. Compared with the blank control group, c-Myc gene expression was reduced in the tumors of the five experimental groups., Conclusion: The results showed that DC-CIK cells stimulated by different methods were highly effect against MDA-MB-231 breast cancer stem cells in nude mice in all groups, especially in group L-D. DC-CIK immunotherapy may provide a new strategy for the clinical treatment of breast cancer.