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Resveratrol, a natural polyphenolic antioxidant, has been reported to possess the cancer chemopreventive potential in wide range by means of triggering tumor cells apoptosis through various pathways. It induced apoptosis through the activation of the mitochondrial pathway in some kinds of cells. In the present reports, we showed that resveratrol-induced HepG2 cell apoptosis and mitochondrial dysfunction was dependent on the induction of the mitochondrial permeability transition (MPT), because resveratrol caused the collapse of the mitochondrial membrane potential (DeltaPsi(m)) with the concomitant release of cytochrome c (Cyt.c). In addition, resveratrol induced a rapid and sustained elevation of intracellular [Ca(2+)], which compromised the mitochondrial DeltaPsi(m) and triggered the process of HepG2 cell apoptosis. In permeabilized HepG2 cells, we further demonstrated that the effect of the resveratrol was indeed synergistic with that of Ca(2+) and Ca(2+) is necessary for resveratrol-induced MPT opening. Calcium-induced calcium release from mitochondria (mCICR) played a key role in mitochondrial dysfunction and cell apoptosis: (1) mCICR inhibitor, ruthenium red (RR), prevent MPT opening and Cyt.c release; and (2) RR attenuated resveratrol-induced HepG2 cell apoptotic death. Furthermore, resveratrol promotes MPT opening by lowering Ca(2+)-threshold. These data suggest modifying mCICR and Ca(2+) threshold to modulate MPT opening may be a potential target to control cell apoptosis induced by resveratrol.

Onnia includes white rotting polypores with annual basidiocarps, a duplex context, monomitic hyphal structure, hymenial setae, and hyaline, thin-walled, smooth basidiospores. Specimens of Onnia, originating mainly from East Asia, Europe, and North America, were studied using both morphology and phylogenetic analyses. Our concatenated data set was derived from 25 collections and included (i) 25 nuc rDNA internal transcribed spacer region sequences (ITS1-5.8S-ITS2 = ITS), 17 generated in this study; and (ii) 14 nuc rDNA 28S rDNA sequences, including the D1-D2 domains, 11 of them generated in this study. The resulting maximum likelihood and Bayesian phylogenies recovered all sampled collections of Onnia as a well-supported clade. In this clade, three previously accepted species, viz., Onnia leporina, O. tomentosa, and O. triquetra, received strong support, whereas three additional lineages with strong support represent the new species described in this paper, O. subtriquetra, O. microspora, and O. tibetica. Of the six Onnia species occurring on gymnosperms, O. tomentosa and O. leporina grow mainly on Picea and have circumboreal distribution in the Northern Hemisphere. In contrast, other species that mostly grow on Pinus are geographically restricted to limited regions, viz., O. triquetra in Europe, O. subtriquetra in North America, and O. microspora and O. tibetica in Asia.

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Construction of a monoclonal antibody (mAb) bank containing a vast variety of antibodies against human tissue proteins is important for proteomic research. A novel strategy of subtractive immunization using fractionated native proteins was developed for high throughput generation of mAb against human plasma proteins. By this novel approach, the bottleneck of antigen preparation can be overcome by combining repeated immunization of animals with subtracted fractions of plasma or tissue proteins and identification of target antigen by immunoprecipitation/mass spectrum strategies. Plasma freshly collected from healthy adults was pooled and three fractions were prepared by size exclusion chromatography. Mice were immunized with the fractionated plasma proteins, and 205 strains of hybridomas secreting mAb were obtained after two-round subtractive immunizations and cell fusions. In the first round, 110 strains of hybridomas were established, in which 77 strains secreting mAb were identified against 10 human plasma high-abundant proteins. In the second round, plasma fraction I was absorbed with mAb against IgM, IgG, ceruloplasmin and haptoglobin. The absorbed fraction I was used as immunogen for the second round immunization and cell fusion. Ninety-five strains of hybridomas secreting mAb were obtained. Although the target antigens of mAb from 82 strains of hybridomas were identified as IgM, IgA, alpha2-macroglobulin and fibrinogen, about 85% antibodies obtained from this round were identified as new antibodies when compared with mAb obtained in the first round immunization with plasma fraction I. The results suggest that subtractive immunization with fractionated plasma proteins followed by identification of antigens with immunoprecipitation/mass spectrum may be an effective approach for rapid preparation of mAb against high-and medium-abundant plasma or tissue proteins.

Sidera is a polypore genus with white to cream or buff basidiomata, whose species in Hymenochaetales are poorly known. We study the phylogeny and diversity of Sidera based on our recent collections from tropic and subtropic Asian-Pacific regions. Phylogenetic analyses based on the internal transcribed spacer (ITS) and nuclear large subunit (nLSU) ribosomal RNA gene regions indicate that ten terminal lineages are well supported within Sidera. Based on morphological examination and phylogeny, four new species, viz. Sidera minutissima, S. parallela, S. srilankensis and S. tenuis are described, and a new combination, Sidera minutipora, is proposed. All these species are illustrated. Sidera minutissima is characterized by tiny basidiomata with bluish pores when fresh, generative hyphae dominating at the dissepiment edges, the presence of cystidioles, and allantoid basidiospores measuring 3.8–4.4 × 0.9–1.3 μm. Sidera parallela differs from other poroid species in the genus by having parallel tramal hyphae in combination with lunate basidiospores measuring 2.8–3.3 × 0.9–1.2 μm. Sidera srilankensis have generative and skeletal hyphae co-dominating at the dissepiment edges, and lunate basidiospores measuring 3.5–4 × 1–1.3 μm. Sidera tenuis is distinguished by small pores (8–10 per mm) and relatively long allantoid basidiospores measuring 4.2–5 × 0.8–1 μm. Sidera minutipora is characterized by buff to olivaceous buff basidiomata when dry, 5–7 pores per mm, rosette-like crystals rare, and allantoid basidiospores measuring 3.7–4.3 × 1–1.3 μm. An identification key to all accepted species is provided.

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