Indocyanine green (ICG) encapsulated hyaluronic acid (HA) nanogels were first studied for highly selective detection of specific cancers and lymph nodes via hyaluronidase sensitive switch-on of near infrared fluorescence as a long-lasting and stimuli-responsive imaging probe.

The cytotoxic and antitumor activity of methanolic extract of rice hulls (MERH) were evaluated by the MTT-dye reduction assay against human colon cancer cells and the colonic aberrant crypt foci (ACF) assay in 1,2-dimethylhydrazine (DMH)-injected F344 male rats, respectively. MERH was found to be highly cytotoxic, with IC50 values of 0.5 microg/mL in vitro. Forty weeks of MERH supplementation (50 mg/kg of body weight/day) reduced colonic pre-neoplastic ACF formation by 35% (p < 0.01). An active compound, momilactone B, was isolated from MERH by silica gel chromatography, Sephadex LH-20 chromatography, and HPLC. The cytotoxic activity of momilactone B was evaluated by the MTT-dye reduction, lactate dehydrogenase (LDH), and colony-forming ability assays in human colon cancer HT-29 and SW620 cells. The results indicated that momilactone B from rice hulls might be a new candidate for chemotherapeutic agent against human colon cancer.

Neural stem cells (NSCs) are capable of giving rise to neurons, glia, and astrocytes. Although self-renewal and differentiation in NSCs are regulated by many genes, such as Notch and Numb, little is known about the role of defective genes on the self-renewal and differentiation of NSCs from developing brain. The Niemann-Pick type C1 (NPC1) disease is a neurodegenerative disease caused by a mutation of the NPC1 gene that affects the function of the NPC1 protein. The ability of NSC self-renewal and differentiation was investigated using a model of NPC1 disease. The NPC1 disorder significantly affected the selfrenewal ability of NSCs, as well as the differentiation. NSCs from NPC1Ϫ/Ϫ mice showed impaired self-renewal ability compared with the NPC1 ϩ/ϩ mice. These alterations were accompanied by the enhanced activity of p38 mitogen-activated protein kinases (MAPKs). Further, the specific p38 MAPK inhibitor SB202190 improved the selfrenewal ability of NSCs from NPC Ϫ/Ϫ mice. This indicated that the NPC1 deficiency can lead to lack of selfrenewal and altered differentiation of NSCs mediated by the activation of p38 MAPK, impairing the generation of neurospheres from NPC1 Ϫ/Ϫ . Thus, the NPC1 gene may play a crucial role in NSC self-renewal associated with p38 MAPK. STEM CELLS 2006;24:292-298

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Stem cell-based therapy has recently emerged for use in novel therapeutics for incurable diseases. For successful recovery from neurologic diseases, the most pivotal factor is differentiation and directed neuronal cell growth. In this study, we fabricated three different widths of a micro-pattern on polydimethylsiloxane (PDMS; 1, 2, and 4 microm). Surface modification of the PDMS was investigated for its capacity to manage proliferation and differentiation of neural-like cells from umbilical cord blood-derived mesenchymal stem cells (UCB-MSCs). Among the micro-patterned PDMS fabrications, the 1 microm-patterned PDMS significantly increased cell proliferation and most of the cells differentiated into neuronal cells. In addition, the 1 microm-patterned PDMS induced an increase in cytosolic calcium, while the differentiated cells on the flat and 4 microm-patterned PDMS had no response. PDMS with a 1 microm pattern was also aligned to direct orientation within 10 degrees angles. Taken together, micro-patterned PDMS supported UCB-MSC proliferation and induced neural like-cell differentiation. Our data suggest that micro-patterned PDMS might be a guiding method for stem cell therapy that would improve its therapeutic action in neurological diseases.

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Heat treatment of persimmon peel (PP) increased the antioxidative activity of the 70% ethanolic extract (EE) and water extract (WE) from PP. EE and WE both prevented H2O2-induced DNA damage to human peripheral lymphocytes. The antioxidative and antigenotoxic activities of the PP extracts were significantly affected by heating.

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