Chemical properties of wood are under stronger genetic control than growth traits in Populus tomentosa Carr.

International audienceContexthe genetic development of some wood quality characteristics in early stage is particularly attractive since these properties are generally inherited. A clear understanding of the genetic control of chemical properties of wood (extractives, holocellulose, and lignin content) and growth traits (tree height, diameter at breast height, and stem volume) of corewood is a prerequisite for breeding for higher wood quality in triploid hybrid clones of Populus tomentosa.• Aims The experiments aimed at unraveling genetic effect and clone × site interactions on chemical properties of wood and growth traits of corewood derived from triploid hybrid clones of P. tomentosa.• Methods Four 5-year-old clonal trials established in northern China were used to determine the clonal variations and clone × site interactions of chemical properties of wood and growth traits. Two hundred sixteen trees from nine clones were sampled in the four sites.• Results Site had a highly significant (P < 0.001) effect on extractives and tree growth and a moderate effect on lignin and holocellulose. Clonal effects were also significant (P < 0.05) for all studied traits. Clone × site interactions were significant for all studied traits except for holocellulose. No significant estimated correlations between chemical properties of wood and growth traits were observed. However, a weak and negative estimated correlation between lignin and growth traits existed. This suggests that selection for growth traits might lead to a minor reduction in lignin in triploid breeding of P. tomentosa.• Conclusions Our results revealed that chemical properties of wood were under stronger genetic control than growth traits in triploid hybrid clones of P. tomentosa. Therefore, breeding programs might be able to improve these chemical properties of wood and growth traits in these hybrids

Evaluation of Adsorption Equilibrium Models by Means of Data Obtained for Oxygen and Nitrogen on Zeolite 5A

Both fugacity and the Lewis–Randall fugacity rule have been incorporated in the vacancy solution and ideal adsorbed solution theories, and in a simplified statistical thermodynamic model, to allow these various approaches to predict adsorption equilibria at elevated pressures. Adsorption equilibrium data for oxygen and nitrogen determined at 273.15, 293.15 and 313.15 K at pressures up to 60 atm have been compared with the values calculated from these models using regression parameters obtained from adsorption isotherms for the pure components. Of these various models, the vacancy solution theory with the Wilson equation and the ideal adsorbed solution theory provided the closest prediction to the experimental data

GRP78 protects CHO cells from ribosylation

D-Ribose (Rib), a reactive glycation compound that exists in organisms, abnormally increases in the urine of diabetic patients and can yield large amounts of advanced glycation end products (AGEs), leading to cell dysfunction. However, whether cellular proteins are sensitive to this type of glycation is unknown. In this study, we found that cellular AGEs accumulate in Chinese hamster ovary (CHO) cells with increased Rib concentration and administration time. Mass spectrum analysis of isolated AGE-modified proteins from cell lysates showed that glucose-regulated protein 78 kD (GRP78) is one of the main ribosylated proteins. Co-immunoprecipitation assays further confirmed the interaction between AGEs and GRP78. Compared with D-glucose (Glc), Rib produced much more AGEs in cells. In kinetic studies, the first order rate constant of LDH released from CHO cells incubated with Rib was nearly 8-fold higher than that of Glc, suggesting that Rib is highly cytotoxic. Immunofluorescent co-localization analysis manifested partial superimposition of AGEs and GRP78, which were distributed throughout the endoplasmic reticulum. Western blotting showed that the expression of GRP78 is up-regulated and then down-regulated in CHO cells during Rib treatment. In the presence of Rib, the suppression of GRP78 expression either with transfected siRNA or with the inhibitor (-)-epigallocatechin gallate (EGCG) dramatically increased AGE levels and decreased cell viability compared with these parameters in the control groups. GRP78 over-expression decreased AGE levels and rescued the cells from Rib-induced cytotoxicity. These data indicate that GRP78 plays a role in preventing Rib-induced CHO cell cytotoxicity.</p

Structural Characteristics of Polysaccharide GP2a in Gardenia jasminoides and Its Immunomodulatory Effect on Macrophages

Here, we elucidated the structural characteristics of a polysaccharide isolated from Gardenia jasminoides Ellis (labeled as GP2a) and its immunomodulatory activity. GP2a is an acidic polysaccharide with a molecular weight of 44.8 kDa, mostly comprising galacturonic acid. Methylation analysis revealed 4-GalpA (74.8%) to be the major sugar residue in GP2a. Nuclear magnetic resonance analysis indicated that its main chain comprised &rarr;4)-&alpha;-D-GalpA-6-OMe-(1&rarr;4)-&alpha;-D-GalpA-(1&rarr; and &rarr;4)-&alpha;-D-GalpA-6-OMe-(1&rarr;2)-&alpha;-L-Rhap-(1&rarr;, with galactan and arabinans linked to the C-4 position of &rarr;2)-&alpha;-L-Rhap-(1&rarr; residue as branched chains. Furthermore, GP2a showed no obvious toxicity to macrophages (RAW 264.7) while enhancing cell viability in a dose- and time-dependent manner. Compared with untreated cells, nitric oxide production and secretion of cytokines, such as tumor necrosis factor-&alpha;, interferon-&gamma;, interleukin (IL)-1&beta;, IL-6, and granulocyte macrophage colony stimulating factor, in GP2a-treated cells significantly increased after 48 h. At 300 &micro;g/mL GP2a concentration, there was no significant difference in the cytokine levels in GP2a- and lipopolysaccharide-treated cells (the positive control). In summary, GP2a is a pectic polysaccharide with homogalacturonan and rhamnogalacturonan-I structural regions in the main chain. Based on its immunomodulatory effects in vitro, GP2a may have potential uses in functional food and medicine

Antibody selection using clonal cocultivation of Escherichia coli

We describe a method for the rapid selection of functional antibodies. The method depends on the cocultivation of that produce phage with target eukaryotic cells in very small volumes. The antibodies on phage induce selectable phenotypes in the target cells, and the nature of the antibody is determined by gene sequencing of the phage genome. To select functional antibodies from the diverse antibody repertoire, we devised a selection platform that contains millions of picoliter-sized droplet ecosystems. In each miniecosystem, the bacteria produce phage displaying unique members of the antibody repertoire. These phage interact only with eukaryotic cells in the same miniecosystem, making phage available directly for activity-based antibody selection in biological systems