Effects of FGF2 and TGFbeta1 on the differentiation of human dental pulp stem cells in vitro

Two crucial growth factors, FGF2 and TGFbeta1, were investigated in this study to determine their inductive effects on the odontoblastic differentiation of human dental pulp stem cells (DPSCs) in vitro. DPSCs were isolated by immunomagnetic bead selection using the STRO-1 antibody, and then co-cultured respectively with FGF2, TGFbeta1 and FGF2+TGFbeta1. The results showed that FGF2 can exert a significant effect on the cell proliferation, while TGFbeta1 or FGF2+TGFbeta1 can initiate an odontoblast-like differentiation of DPSCs. Moreover, FGF2 can synergistically upregulate the effects of TGFbeta1 on the odontoblastic differentiation of DPSCs, as indicated by the increased alkaline phosphatase activity, the polarized cell appearance and secretary ultrastructural features, the formation of mineralized nodules and the gene/protein expression of dentin sialoprotein and dentin matrix protein-1. Together, FGF2 acted primarily on the cell proliferation, while TGFbeta1 and FGF2+TGFbeta1 mainly stimulated the odontoblastic differentiation of DPSCs. This study provides interesting progress in the odontoblastic differentiation of DPSCs induced by FGF2 and TGFbeta1.     

Molecular Characterization of Phytoplasma Associated with Rose Witches'-Broom in China

In 2005, rose plants (Rosa rugosa cv. ‘Plena’) exhibiting typical phytoplasma disease symptoms of stunting, yellowing, witches’‐broom and dieback were observed in Pingyin, Shandong Province, China. The disease, rose witches’‐broom (RoWB), is progressively destructive and can be graft‐transmitted. Polymerase chain reaction (PCR), sequencing of PCR products and electron microscopy were used to investigate the possible association of phytoplasma with RoWB. All results indicated that presence of phytoplasma in the symptomatic rose plants. Sequence alignment of 16S rRNA gene, tuf gene and rp gene confirmed that the phytoplasma associated with RoWB is the causal agent of Paulownia witches’‐broom disease, which might be transmitted from the paulownia tree that is several meters away. To our knowledge, this is the first report of the molecular characterization of phytoplasma infecting rose in China.     

Intensity and Importance of Competition for a Grass (Festuca rubra) and a Legume (Trifolium pratense) Vary with Environmental Changes

How plant competition varies across environmental gradients has been a long debate among ecologists. We conducted a growth chamber experiment to determine the intensity and importance of competition for plants grown in changed environmental conditions. Festuca rubra and Trifolium pratense were grown in monoculturs and in two- and/or three-species mixtures under three environmental treatments. The measured competitive variations in terms of growth (height and biomass) were species-dependent. Competition intensity for Festuca increased with decreased productivity, whilst competition importance displayed a humpback response. However, significant response was detected in neither competition intensity nor importance for Trifolium. Intensity and importance of competition followed different response patterns, suggesting that they may not be correlated along an environmental gradient. The biological and physiological variables of plants play an important role to determine the interspecific competition associated with competition intensity and importance. However, the competitive feature can be modified by multiple environmental changes which may increase or hinder how competitive a plant is.     

Effects of sheep urine on growth characteristics of different life form plants in a Chinese steppe grassland

The effects of sheep urine deposition volume (0, 1, 2 or 4 L/m²) and deposition stage of plant growth (vegetative or reproductive) on the number and size of tillers/branches and the biomass of Stipa bungeana, Artemisia capillaries and Lespedeza davurica in a Chinese steppe grassland were determined. The results indicate that the response of the three plant species to sheep urine deposition differs, and is influenced by both urine deposition volume and deposition stage of plant growth. Urine deposition had a short-term scorch effect on grassland plants, which mainly occurred in the inner zone of urine patches. Urine application had a long-term positive effect on S. bungeana and a long-term negative effect on A. capillaries and L. davurica, which lasted at least two years and decreased with decrease in urine deposition volume. All species growing in the inner zone of urine patches were scorched by sheep urine deposition, some species in the marginal zone of patches were also scorched, while no species were scorched in the outer zones. The reproductive and vegetative stages of A. capillaries and the reproductive stages of S. bungeana and L. davurica were sensitive to sheep urine deposition.     

Exquisite binding specificity of <Emphasis Type="Italic">Sclerotium rolfsii</Emphasis> lectin toward TF-related O-linked mucin-type glycans

Sclerotium rolfsii lectin (SRL), a secretory protein from the soil borne phytopathogenic fungus Sclerotium rolfsii, has shown in our previous studies to bind strongly to the oncofetal Thomson-Friedenreich carbohydrate (Galβ1-3GalNAc-ser/thr, T or TF) antigen. TF antigen is widely expressed in many types of human cancers and the strong binding of SRL toward such a cancer-associated carbohydrate structure led us to characterize the carbohydrate binding specificity of SRL. Glycan array analysis, which included 285 glycans, shows exclusive binding of SRL to the O-linked mucin type but not N-linked glycans and amongst the mucin type O-glycans, lectin recognizes only mucin core 1, core 2 and weakly core 8 but not to other mucin core structures. It binds with high specificity to “α-anomers” but not the “β-anomers” of the TF structure. The axial C4-OH group of GalNAc and C2-OH group of Gal is both essential for SRL interaction with TF disaccharide, and substitution on C3 of galactose by sulfate or sialic acid or N-acetylglucosamine, significantly enhances the avidity of the lectin. SRL differs in its binding to TF structures compared to other known TF-binding lectins such as the Arachis hypogea (peanut) agglutinin, Agaricus bisporus (mushroom) lectin, Jackfruit, Artocarpus integrifolia (jacalin) and Amaranthus caudatus (Amaranthin) lectin. Thus, SRL has unique carbohydrate-binding specificity toward TF-related O-linked carbohydrate structures. Such a binding specificity will make this lectin a very useful tool in future structural as well as functional analysis of the cellular glycans in cancer studies.     

Molecular identification of endophytic fungi from medicinal plant <Emphasis Type="Italic">Huperzia serrata</Emphasis> based on rDNA ITS analysis

Fifty-two endophytic fungi strains with different colony morphologies were isolated from stems, leaves and roots of Huperzia serrata (Thunb. ex Murray) Trevis. collected from Bawangling Reserve of Hainan Province in southern China. They were identified mainly based on rDNA ITS sequences and phylogenetic analysis. The results showed that all strains belonged to four classes, i.e. Sordariomycetes (92.31%), Dothideomycetes (3.85%), Pezizomycetes (1.92%) and Agaricomycetes (1.92%). Forty-seven strains were identified at the genus level, including Glomerella (Colletotrichum), Hypocrea (Trichoderma), Pleurostoma, Chaetomium, Coniochaeta (Lecythophora), Daldinia, Xylaria, Hypoxylon, Nodulisporium, Cazia and Phellinus. As to the other five strains, three were identified at the order level and two at the family level, indicating that a great diversity of fungi taxa exists in H. serrata. Most isolated strains belonged to the genus of Glomerella (Colletotrichum) and Hypoxylon, twenty-one from Glomerella and its anamorph Colletotrichum (42.3% of total isolated strains) and ten from Hypoxylon (19.2% of total isolated strains). Pleurostoma, Chaetomium, Coniochaeta (Lecythophora), Daldinia, Xylaria, Hypoxylon, Nodulisporium, Cazia and Phellinus were reported as endophytic fungi isolated from H. serrata for the first time.     

Nonsynonymous substitution rate (Ka) is a relatively consistent parameter for defining fast-evolving and slow-evolving protein-coding genes

Background  

Mammalian genome sequence data are being acquired in large quantities and at enormous speeds. We now have a tremendous opportunity to better understand which genes are the most variable or conserved, and what their particular functions and evolutionary dynamics are, through comparative genomics.     

Identification of two novel missense WFS1 mutations,H696Y and R703H,in patients with non-syndromic low-frequency sensorineural hearing loss

Non-syndromic low-frequency sensorineural hearing loss(LFSNHL) is an unusual type of hearing loss in which frequencies≤2000 Hz predominantly are affected.To date,different mutations in two genes,DIAPH1 and WFS1,have been found to be associated with LFSNHL. Here,we report a five-generation Chinese family with postlingual and progressive LFSNHL.We mapped the disease locus to a 2.5 Mb region on chromosome 4p16 between markers SNP_A-2167174 and D4S431,overlapping with the DFNA6/14/38 locus.Sequencing of cand...     

Theoretical and experimental studies of the radiative properties of matter at high energy densities and their application to the problems of inertial confinement fusion

The paper presents the results of theoretical and experimental studies of the radiative properties of plasmas produced by heating and compression of various materials to high energy densities. The specific features of the theoretical plasma model known as the ion model, which is used to calculate the radiative characteristics of plasmas of complex chemical composition, are discussed. The theoretical approach based on this model is applied to the plasma produced during the explosion of the X-pinch wires. The theoretical estimate of the radiation efficiency is compared with the experimental data on the total energy yield from an X-pinch made of two different wires (NiCr and Alloy 188). The radiative characteristics of (C12 H16 O8) and (C8 H12 O6) plasmas are calculated for the temperature diagnostics of plasmas produced from porous targets employed in inertial confinement fusion experiments with the use of laser radiation and heavy-ion beams.