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The fruiting bodies of Isaria fungi have been traditionally used in Korea to treat cancer. An apoptosis-inducing compound, 4-acetyl-12,13-epoxyl-9-trichothecene-3,15-diol, was isolated from the methanol extract of fruiting bodies of Isaria japonica YASUDA by bioassay-guided fractionation. The apoptosis of the human leukemia cells (HL-60) by the compound was accessed by propidium iodide-staining flow cytometric analysis, and apoptosis-inducing activity at IC 50 concentration (10 nmol/l) was further confirmed by a nuclear morphological change, a ladder pattern of internucleosomal DNA fragmentation, and an activation of caspase-3.Key words Isaria japonica YASUDA; human HL-60 leukemia cell; 4-acetyl-12,13-epoxyl-9-trichothecene-3,15-diol; apoptosis japonica were inoculated into potato dextrose agar, and incubated at 25°C until the fungal colony grow to 5 cm in diameter. It usually took 10 d, and the colony turned gray. The cultures were then refrigerated at approximately 4°C, and used as stock cultures. In the second culture, a 1 l flask, containing 500 ml of culture medium, which had been sterilized at 121°C for 20 min and then cooled to 15°C, was inoculated with four 5-mm agar plugs taken from stock cultures. The flask culture was aerated by agitation on an orbital shaker at 140 rpm for a period of 3 d at 25°C, then at 160 ppm for 4 d. The culture medium consists of potato (200 g/l) and sugars (30 g/l). All cultures were conducted in the dark room. The third fermentation was carried out in the pupae of the silkworm (100 g). The fermentation media were autoclaved at 121°C for 40 min. After the media had cooled to 15°C, they were inoculated with 5 ml of spore inoculum and incubated for 8 d at 25°C in the dark room. After 8 d of cultivation, the culture condition was changed to 60% humidity for 10 d in the dark room, then 80% humidity at 20°C in 2000 lux of brightness for 30 d. After incubation, the fruiting bodies of the fungi were harvested, and extracted with MeOH for further chemical and biological investigations.Isolation and Structure Determination of 4-Acetyl-12,13-epoxy-9-trichothecene-3,15-diol The air-dried fruiting bodies (226 g) from the fermentation of I. japonica were extracted with methanol (MeOH) for 48 h. The MeOH extract was concentrated, suspended in H 2 O, and sequentially partitioned with n-hexane, CH 2 Cl 2 , and ethyl acetate (EtOAc). The EtOAc-soluble fraction (247.5 mg) was subjected to C18 flash column chromatography with a stepwise gradient of 30 to 100% (v/v) MeOH in H 2 O. The fractions eluting at 30% and 40% MeOH in H 2 O (36.8 mg) were combined, and subjected to preparative reversed-phase HPLC using a gradient from 15 to 35% CH 3 CN in H 2 O over 40 min, then 100% CH 3 CN for 10 min (Alltech HS Hyperprep 100 BDS C 18 (1.0ϫ25 cm; 8-mm particle size; 2 ml/min; UV detection at 210 nm)) to yield compound 1 (12.3 mg). The structure of compound 1 was identified as 4-acetyl-12,13-epoxy-9-trichothecene-3,15-diol (AEDT) by the comparison of MS and NMR data with those reported in the literature ...

The Scrophularia buergeriana (SB) has long been used to treat various diseases an account of its antimicrobial and anti-virus activity. However, it is unclear how SB regulates the immune responses. This study investigated the effect of SB on the production of cytokines in a human T-cell line, MOLT-4 cells, and mouse peritoneal macrophages. The MOLT-4 cells were cultured for 24 h in the presence or absence of SB plus concanavalin (con) A. SB plus con A significantly increased the level of interleukin (IL)-2, IL-4 and interferon (IFN)-gamma production compared with that of con A alone (approximately 1.79-fold for IL-2, 2-fold for IL-4, and 1.85-fold for IFN-gamma, p < 0.05). SB plus recombinant IFN-gamma (rIFN-gamma) increased the level of IL-12 and NO production compared with rIFN-gamma alone. In addition, SB plus rIFN-gamma increased the level the iNOS expression on mouse peritoneal macrophages. Overall, SB may have an immune-enhancement effect through cytokine production.

This paper predicted nonlinear dynamic responses of a cantilevered carbon nanotube(CNT) resonator incorporating the electrostatic forces and van der Waals interactions between the CNT cantilever and ground plane. The structural model of CNT includes geometric and inertial nonlinearities to investigate various phenomena of nonlinear responses of the CNT due to the electrostatic excitation.In order to solve this problem, we used Galerkin's approximation and the numerical integration techniques. As a result, the CNT nano-resonator shows the softening effect through saddle-node bifurcation near primary resonance frequency with increasing the applied AC and DC voltages. Also we can predict nonlinear secondary resonances such as superharmonic and subharmonic resonances.The superharmonic resonance of the nano-resonator is influenced by applied AC voltage. The period-doubling bifurcation leads to the subharmonic resonance which occurs when the nano-resonator is actuated by electrostatic forces as parametric excitation. 는 선형보로 가정한 CNT의 구형파 전압가진

Black pine barks from the southern region of Korea were extracted using pressurized hot water and the water soluble extracts were then separated in a stepwise fashion using a variety of solvents, column chromatography (CC), thin layer chromatography (TLC), and high pressure liquid chromatography (HPLC). The antioxidant activities of each fraction and the active compounds were determined based on the radical scavenging activities of 2,2-diphenyl-1-picrylhydrazyl (DPPH), reductive potential of ferric ion, and total phenol contents. A DPPH test showed that the half maximal effective concentration (EC50 value : 6.59 ± 0.31 μg/mL) of the ethyl acetate fraction (ca. 0.67%) was almost the same as that of the control compounds and inversely proportional to the value of the total phenol contents. The cell viability of the water extracts was confirmed by methyl thiazol-2-yl-2,5-diphenyl tetrazolium bromide (MTT) with enzyme linked immune sorbent assay (ELISA). Catechin, epicatechin, quercetin and ferulic acid were isolated from the ethyl acetate fraction as active compounds and identified by nuclear magnetic resonance. The antioxidant activity as value of DPPH of each of the separated compounds was lower than the ethyl acetate fraction, and ferulic acid was the lowest among these compounds.