Comparison of structural characteristics and anti-tumor activity of two alkali extracted peach gum arabinogalactan.

Two polysaccharides, PGP-90 and PGP-100 (molecular weights of 7.59 × 102 kDa and 10.48 × 102 kDa, respectively), were isolated from Peach gum using alkaline electrolyte water as an extraction solution. Structural characterization showed that PGP-90 and PGP-100 are AG-II arabinogalactans with ß-D-(1 â†’ 6)-Galp as the main chain and 1 â†’ 3 Araf and 1 â†’ 5 Araf branched chains at O-3 and O-4 positions. Animal experiments showed that PGP-90 and PGP-100 significantly improved immune function, enhance the proliferative capacity of lymphocytes and phagocytosis of peritoneal macrophages, and regulated the ratio of lymphocyte subpopulations in S180 tumor-bearing mice. Meanwhile, PGP-90 and PGP-100 promoted the secretion of cytokines (TNF-α, IFN-γ, and IL-2) by activated macrophages and blocked apoptosis at the G1 phase, resulting in tumor suppression rates of 40.80 % and 46.30 % (100 mg/kg), respectively, with PGP-100 demonstrating stronger in vivo anti-tumor activity. The above experimental results indicate that Peach gum polysaccharides have the potential to be functional anti-tumor agents.

Selenochemical modification of low molecular weight polysaccharides from Grifola frondosa and the mechanism of their inhibitory effects on gastric cancer cells.

An important micronutrient involved in immune response and antitumor is selenium. LMW-GFP, a polysaccharide extracted from Grifola frondosa seed bodies, has a relatively weak antitumor effect on BGC-823 and MFC cells in vitro, whereas selenium binding to LMW-GFP can significantly increase the in vitro antitumor activity of LMW-GFP. In this study, Se-LMW-GFP was prepared by the HNO3-Na2SeO3 method, and the structures of LMW-GFP and Se-LMW-GFP were characterized by UV-visible spectroscopy of absorption, FTIR spectroscopy, and electron scanning microscopy, and these structural analyses showed that selenium was successfully complexed to LMW-GFP. The selenium content of Se-LMW-GFP was measured to be 2.08 % ± 0.08 % by ICP-MS. The anti-tumor activity of LMW-GFP before and after selenium modification was compared by cellular experiments, and the findings indicated that the anti-tumor activity of Se-LMW-GFP was considerably improved over that of LMW-GFP, and inhibited the proliferation of BGC-823 cells and MFC cells through a combination of the Fas/FasL-mediated exogenous death receptor pathway as well as the endogenous mitochondrial pathway. Our results suggest that Se-LMW-GFP not only has great potential for natural health food and anti-gastric cancer drug development but is also a good selenium supplement.

Dead Reasons and Related Factors of 42 Cases with Acute Leukemia in Chinldren / 实用儿科临床杂志

Objective To explore the dead reasons and related factors of acute leakemia(AL)in children.Methods The clinical data of 42 dead cases of children with AL,who were admitted to Guangzhou Children's Hospital between Jan.1999 and Mar.2007 were reviewed.Nineteen cases were boys,23 cases were girls;the aging from 4 months to 12 years old and 5 months.Of 42 children,21 cases were acute lymphoblastic leukemia(ALL),18 cases were acute myeloid leukemia(AML),3 cases were unclassified AL.Results Ten out of 12 early-dead cases died of bleeding.Among 30 cases who received chemotherapy,4 cases died of bleeding,others of myelosuppression combined with infection,14 of whom died from sepsis,3 cases with fungal infection,1 case with virus infection,4 cases with unknown pathogens.Sixteen children relapsed among those who got remission,half of them relapsed within 1 year since diagnosed.Treatment-related mortality(TRM)was 90%(27 out of 30 cases).The main causes of TRM were infection and hemorrhage.Hyperleukocytosis and bleeding were 2 risk factors related to early death in new-diagnosed children.Conclusions More emphasizes should be put on bleeding tendency during early treatment in children with AL and treatment of infection complications during induction chemotherapy to reduce TRM.