A new lanostanoid ester glucoside, 3 alpha-acetoxy-5 alpha-lanosta-8,24-dien-21-oic acid ester beta-d-glucoside (1), and a known steroid, 2 beta,3 alpha,9 alpha-trihydroxy-5 alpha-ergosta-7,22-diene (2), were isolated from the fruit bodies of Ganoderma tsugae and their structures determined by spectroscopic methods. To study the cytotoxicity of 1 and 2, the changes of DNA content in human hepatocytes (Hep 3B) were studied. A sub-G1 cell stage was drastically increased after 24-h incubation with 1 (24 micrograms/mL). Compound 2 (100 micrograms/mL) inhibited the cell cycle progression of Hep 3B cells at the G2/M phase with an IC50 value of about 87.1 micrograms/mL. These results indicate that 1 causes cell death by apoptosis and 2 may possess the activity of cell cycle inhibition.

Three new compounds, (24R, S)-3alpha-acetoxy-24-hydroxy-5alpha-lanosta-8,25-di en-21-oic acid, named tsugaric acid C (1); 3alpha-acetoxy-5alpha-lanosta-8, 24-diene-21-O-beta-D-xyloside, named tsugarioside B (2); and 3alpha-acetoxy-(Z)-24-methyl-5alpha-lanosta-8,23,25-tr ien-21-oic acid ester beta-D-xyloside, named tsugarioside C (3), and a mixture of two known steroids were isolated from the fruit bodies of Ganoderma tsugae. The structures of 1-3 were determined by spectral and chemical methods. The cytotoxic activity of the lanostanoid constituents of this fungus was evaluated against several different cancer cell lines.

A refined formulation of composite sandwich plate is employed to study the dynamic response of impacted sandwich plate. In this refined formulation, the faces of the sandwich plate are modeled as two separate Mindlin plates whereas the core is con sidered to have both transverse shear and normal stiffnesses. This model allows the includ ing of relative deformations of two faces under concentrated load. The capability of mod eling relative deformation of two faces is important since the impacted face behaves differently from the opposite one. Finite element method is used to discretize the sandwich plate based on this refined theory. Experimental works are conducted on the impact of [O 2/902/O2/FOAM]s sandwich plate with graphite/epoxy faces and FR10110 rigid foam core. Dynamic strain histories obtained from theoretical analysis and the strain-gage experimen tal results are compared in good agreement. It indicates that the theoretical model employed herein describes the dynamic behavior of composite sandwich plates due to low velocity impact. In addition, effects of impact velocity and mass of the impactor are inves tigated.

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