Effects of soft tissue artifacts on the calculated kinematics and kinetics of the knee during stair-ascent

Biomechanics of the knee during stair-ascent has mostly been studied using skin-marker-based motion analysis techniques, but no study has reported a complete assessment of the soft tissue artifacts (STA) and their effects on the calculated joint center translation, angles and moments at the knee in normal subjects during this activity. This study aimed to bridge the gap. Twelve young adults walked up a three-step stair while data were acquired simultaneously from a three-dimensional motion capture system, a force plate and a dynamic fluoroscopy system. The "gold standards" of poses of the knee were obtained using a 3D fluoroscopy method. The STA of the markers on the thigh and shank were then calculated, together with their effects on the calculated joint center translations, angles and moments at the knee. The STA of the thigh markers were greater than those on the shank, leading to significantly underestimated flexion and extensor moments, but overestimated joint center translations during the first half of the stance phase. The results will be useful for a better understanding of the normal biomechanics of the knee during stair-ascent, as a baseline for future clinical applications and for developing a compensation method to correct for the effects of STA.     

Chemopreventive potential of cyclic diarylheptanoids

Eleven cyclic diarylheptanoids and seven related compounds were screened as potential antitumor promoters by using the in vitro short-term 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced Epstein-Barr virus early antigen (EBV-EA) activation assay. In addition, the cyclic diarylheptanoid myricanone (2) was examined for antitumor initiating activity in a two-stage carcinogenesis assay of mouse skin tumors induced by peroxynitrite as an initiator and TPA as a promoter. Myricanone (2) exhibited significant antitumor-initiating effect on mouse skin. These data suggest that cyclic, as well as linear, diarylheptanoids might be valuable chemopreventors.     

Antitumor agents. Part 204: synthesis and biological evaluation of substituted 2-aryl quinazolinones

A series of 2',3',4',6,7-substituted 2-aryl quinazolinones were synthesized and evaluated for biological activity. Among them, 17 displayed significant growth inhibitory action against a panel of tumor cell lines. Compound 17 was also a potent inhibitor of tubulin polymerization. Compounds 8-10 displayed selective activity against P-gp-expressing epidermoid carcinoma of the asopharynx.     

The modified rice αAmy8 promoter confers high-level foreign gene expression in a novel hypoxia-inducible expression system in transgenic rice seedlings

Expression of α-amylase genes in rice is induced not only by sugar starvation and gibberellin (GA) but also by O₂ deficiency. Promoters of two rice α-amylase genes, αAmy3 and αAmy8, have been shown to direct high-level production of recombinant proteins in rice suspension cells and germinated seeds. In the present study, we modified the cis-acting DNA elements within the sugar/GA response complex (SRC/GARC) of αAmy8 promoter. We found that addition of a G box and duplicated TA box leads to high-level expression of αAmy8 SRC/GARC and significantly enhances αAmy8 promoter activity in transformed rice cells and germinated transgenic rice seeds. We also show that these modifications have drastically increased the activity of αAmy8 promoter in rice seedlings under hypoxia. Our results reveal that the G box and duplicated TA box may play important roles in stimulating promoter activity in response to hypoxia in rice. The modified αAmy8 promoter was used to produce the recombinant human epidermal growth factor (hEGF) in rice cells and hypoxic seedlings. We found that the bioactive recombinant hEGF are stably produced and yields are up to 1.8 % of total soluble protein (TSP) in transformed rice cells. The expression level of synthetic hEGF containing preferred rice codon usage comprises up to 7.8 % of TSP in hypoxic transgenic seedlings. Our studies reveal that the modified αAmy8 promoter can be applicable in establishing a novel expression system for the high-level production of foreign proteins in transgenic rice cells and seedlings under hypoxia.     

Staphylococcus epidermidis in the human skin microbiome mediates fermentation to inhibit the growth of Propionibacterium acnes: implications of probiotics in acne vulgaris

Increasing evidence demonstrates that commensal microorganisms in the human skin microbiome help fight pathogens and maintain homeostasis of the microbiome. However, it is unclear how these microorganisms maintain biological balance when one of them overgrows. The overgrowth of Propionibacterium acnes (P. acnes), a commensal skin bacterium, has been associated with the progression of acne vulgaris. Our results demonstrate that skin microorganisms can mediate fermentation of glycerol, which is naturally produced in skin, to enhance their inhibitory effects on P. acnes growth. The skin microorganisms, most of which have been identified as Staphylococcus epidermidis (S. epidermidis), in the microbiome of human fingerprints can ferment glycerol and create inhibition zones to repel a colony of overgrown P. acnes. Succinic acid, one of four short-chain fatty acids (SCFAs) detected in fermented media by nuclear magnetic resonance (NMR) analysis, effectively inhibits the growth of P. acnes in vitro and in vivo. Both intralesional injection and topical application of succinic acid to P. acnes-induced lesions markedly suppress the P. acnes-induced inflammation in mice. We demonstrate for the first time that bacterial members in the skin microbiome can undergo fermentation to rein in the overgrowth of P. acnes. The concept of bacterial interference between P. acnes and S. epidermidis via fermentation can be applied to develop probiotics against acne vulgaris and other skin diseases. In addition, it will open up an entirely new area of study for the biological function of the skin microbiome in promoting human health.     

TRAF4 participates in Wnt/β-catenin signaling in breast cancer by upregulating β-catenin and mediating its translocation to the nucleus

Tumor necrosis factor receptor-associated factor 4 (TRAF4) is upregulated in various subtypes of breast cancers and cell lines; however, the precise functions of TRAF4 are poorly understood. Our objective was to investigate its relationship with β-catenin. TRAF4 participates in several signaling pathways, such as NF-κB and JNK signaling pathways. In this study, we identified β-catenin as a TRAF4-binding protein, have shown that TRAF4 enhanced expression of β-catenin, and found that TRAF4 mediated the translocation of β-catenin from the cytoplasm to the nucleus, thereby facilitating activation of the Wnt signaling pathway in breast cancer.     

Mitochondrial DNA phylogeography of Semisulcospira libertina (Gastropoda: Cerithioidea: Pleuroceridae): implications the history of landform changes in Taiwan

The mitochondrial DNA cytochrome c oxidase subunit I sequences from 95 specimens of Semisulcospira libertina in Taiwan were identified as two major phylogroups, exhibiting a southern and northern distribution, north of Formosa Bank and south of Miaoli Plateau. The genetic distance between these two phylogroups was 12.20 %, and the distances within-phylogroups were 4.97 and 5.56 %. According to a molecular clock of 1.56 % per lineage per million years, the divergence time between these two major phylogroups was estimated at 4.94 million years ago (mya), with the two phylogroups forming at 3.64 and 3.75 mya, respectively. Moreover, the geological events have suggested that Taiwan Island emerged above sea level at 4–5 mya, and became its present shape at 2 mya. These results suggested that these two phylogroups might originate from two independent ancestral populations or divergent before colonizing Taiwan. Within South phylogroup, the initial colonization was hypothesized to be in Kaoping River (WT), followed by its northward. The high divergence between south- and north of WT River was influenced by the formation of the Kaoping foreland basins. Within North phylogroup, the colonization was from central sub-region through paleo-Miaoli Plateau to northern and northeastern sub-regions. This study showed that the landform changes might have shaped the genetic structure of S. libertina in concert. Apparently, two cryptic species or five different genetic stocks of S. libertina could be identified; these results are useful for the evaluation and conservation of S. libertina in Taiwan.     

Simulation for diffusion behaviour of molecules in nanopattern-supported lipid bilayers based on random walk theory

In both the scientific and the technological approach, molecular manipulation with microscopic obstacles is of great importance. Recently, the application of a self-spreading lipid bilayer has attracted growing interest for its ability to transport any molecule in any desired direction. In this paper, we propose a new model, which imitates a self-spreading lipid bilayer on a substrate with metallic nanobarriers, to simulate the diffusion behaviours of molecules within it based on the random walk (RW) theory. The barriers are designed as Jones Tsai's experiments. The barrier's length, width, spacing, gap and interaction energy with molecules are investigated in this paper. The mean square displacement and diffusion coefficients (D) were calculated based on our simulation results. The results show that our simulation is consistent with the experiments. Comparing with the experimental techniques, this simulation work has improved the time- and space-resolution. Furthermore, it can simulate in rather long time-scale. Our RW models are expected to provide theoretical foundation for single molecular observation of hop diffusion in a lipid bilayer with metallic nanogates.