Estrogen receptor alpha and vitamin D receptor gene polymorphisms and bone mineral density: association study of healthy pre- and postmenopausal Chinese women

In the present study, we tested the association between the estrogen receptor alpha (ER-alpha) and vitamin D receptor (VDR) genes with bone mineral density (BMD). A total of 649 healthy Chinese women, classified as pre-menopausal (N=388) and post-menopausal (N=261) groups, were genotyped at the ER-alpha PvuII, XbaI, and VDR ApaI sites. BMDs at the lumbar spine (L(1)-L(4)) and total hip were measured by dual-energy X-ray absorptiometry. For the VDR ApaI locus, AA carriers had lower spine BMD than Aa (p=0.02) and aa carriers (p<0.01) in the pre-menopausal group. For the ER-alpha gene, carriers of haplotype px had lower spine BMD than the non-carriers (p=0.03) in the pre-menopausal group. Furthermore, we observed significant interaction between the ER-alpha and VDR genes in the post-menopausal group: with AA genotype (or A allele) at the VDR ApaI locus, pX carriers had higher spine BMD than the non-carriers (p=0.02), and PX carriers had lower hip BMD than the non-carriers (p=0.04). Our data suggest that the ER-alpha and VDR genes may be associated with the BMD variation in Chinese women.     

Proteomic analysis of CA1 and CA3 regions of rat hippocampus and differential susceptibility to intermittent hypoxia

The CA1 and CA3 regions of the hippocampus markedly differ in their susceptibility to hypoxia in general, and more particularly to the intermittent hypoxia that characterizes sleep apnea. Proteomic approaches were used to identify proteins differentially expressed in the CA1 and CA3 regions of the rat hippocampus and to assess changes in protein expression following a 6-h exposure to intermittent hypoxia (IH). Ninety-nine proteins were identified, and 15 were differentially expressed in the CA1 and the CA3 regions. Following IH, 32 proteins in the CA1 region and only 7 proteins in the more resistant CA3 area were up-regulated. Hypoxia-regulated proteins in the CA1 region included structural proteins, proteins related to apoptosis, primarily chaperone proteins, and proteins involved in cellular metabolic pathways. We conclude that IH-mediated CA1 injury results from complex interactions between pathways involving increased metabolism, induction of stress-induced proteins and apoptosis, and, ultimately, disruption of structural proteins and cell integrity. These findings provide initial insights into mechanisms underlying differences in susceptibility to hypoxia in neural tissue, and may allow for future delineation of interventional strategies aiming to enhance neuronal adaptation to IH.     

Anti-osteopontin monoclonal antibody prevents ovariectomy-induced osteoporosis in mice by promotion of osteoclast apoptosis

Osteopontin (OPN) is abundant in mineralized tissues and has long been implicated in bone remodeling. However, the therapeutic effect of targeting OPN in bone loss diseases and the underlying molecular mechanism remain largely unknown. Here, we reported that anti-OPN mAb (23C3) could protect against ovariectomy-induced osteoporosis in mice, demonstrated by microcomputed tomography analysis and histopathology evaluation. In vitro assay showed that 23C3 mAb reduced osteoclasts (OCs)-mediated bone resorption through promotion of mature OC apoptosis. Thus, the study has important implications for understanding the role of OPN in OC bone resorption and survival, and OPN antagonists may have therapeutic potential for osteoporosis and other osteopenic diseases.     

Microarray analysis of differentially expressed genes engaged in fruit development between table and wine grape

Microarray analysis of genes can provide individual gene-expression profiles and new insights for elucidating biological mechanisms responsible for fruit development. To obtain an overall view on expression profiles of metabolism-related genes involved in fruit development of table and wine grapes, a microarray system comprising 15,403 ESTs was used to compare the expressed genes. The expression patterns from the microarray analysis were validated with quantitative real-time polymerase chain reaction analysis of 18 selected genes of interest. During the entire fruit development stage, 2,493 genes exhibited at least 2.0-fold differences in expression levels with 1,244 genes being up-regulated and 1,249 being down-regulated. Following gene ontology analysis, only 929 differentially expressed (including 403 up-regulated and 526 down-regulated) genes were annotated in table and wine grapes. These differentially expressed genes were found to be mainly involved in carbohydrate metabolism, biosynthesis of secondary metabolites as well as energy, lipid and amino acid metabolism via KEGG. Our results provide new insights into the molecular mechanisms and expression profiles of genes in the fruit development stage of table and wine grapes.     

Phytoremediation of Pb contaminated soil with polymer-coated EDTA

EDTA-assisted phytoextraction of lead (Pb) has been developed, but concerns have arisen due to the possibility of leaching of both Pb and EDTA to ground water caused by uncontrolled release. We developed five types of controlled-release EDTA (polymer-coated EDTA) by coating the EDTA with a polyolefin polymer. A test of the release rate showed that the duration for the release of 75% of total EDTA ranged from 3 to 210 days. A pot experiment was conducted to compare the effect of these polymer-coated EDTA and non-coated EDTA on the concentrations of Pb and EDTA in soil solution, and Pb accumulation in sorghum (Sorghum bicolor L. cv. EARLY SUMAC) in a Pb-contaminated soil. One of the polymer-coated EDTAs, C-EDTA-4, with a release period of 80 days proved to be the best in decreasing Pb and EDTA concentrations in soil solution, and increasing Pb accumulation in sorghum shoots compared to the direct application of EDTA. Our results suggest that polymer-coated EDTA has a potential for phytoextraction of Pb with a reduced environmental risk.     

Molecular dynamics study on perfect and defective graphene/calcium-silicate-hydrate composites under tensile loading

ABSTRACT

Atomic models of graphene/calcium-silicate-hydrate (G/C-S-H) are constructed by embedding perfect or defective graphene in molecular structures of amorphous C-S-H. Molecular dynamics (MD) simulation is utilised to study mechanical properties of the G/C-S-H and the enhancing effect of perfect and defective graphene is compared. The effects of temperature and strain rate on perfect and defective G/C-S-H are also investigated and compared. The results from present simulations show that (i) the defective graphene has better enhancing effect in C-S-H than perfect one and it grows with the increase of defect sizes; (ii) the tensile strength of G/C-S-H decreases with the increase of temperature and the defective G/C-S-H is more susceptible to temperature than the perfect one; (iii) the ultimate strength and the failure strain increase significantly with the increase of strain rate and the effects of strain rate on perfect and defective G/C-S-H are similar. These findings provide important atomic insights for understanding the mechanical behaviours of G/C-S-H composite.     

Glaucocalyxin A and B Regulate Growth and Induce Oxidative Stress in Lettuce (Lactuca sativa L.) Roots

Glaucocalyxin (Gla) A–C are major ent-kaurane diterpenoids isolated from Isodon japonicus var. glaucocalyx (Maxim.) H. W. Li. This study investigated the possible interference of these diterpenoids with root growth and its mechanism of action in lettuce (Lactuca sativa L.) seedlings. Results indicated the dual stimulatory and inhibitory effects of Gla A and B on root growth and their phytotoxic effects on root hair development. The promotion of root growth by lower levels of Gla A and B (20–40 μM) resulted from enhanced cell length and increased mitotic activity. However, higher concentrations (80–200 μM) of Gla A and B had inhibitory effects. In addition, Gla A and B inhibited root hair development of lettuce seedlings in a dose-dependent manner at concentrations between 20 and 200 μM. Exposure of lettuce roots to Gla A and B at 200 μM increased levels of malondialdehyde and the generation of O ₂ ^·? , indicating lipid peroxidation and induction of oxidative stress. Activities of the antioxidant enzymes superoxide dismutase, catalase, and peroxidase were significantly elevated. Reactive oxygen species (ROS) scavengers dihydroxybenzene disulfonic acid (Tiron) and dimethylthiourea at 100 μM could efficiently alleviate the phytotoxicity induced by Gla A and B at 200 μM. These results demonstrated that the deleterious effect of Gla A and B at higher concentrations (80–200 μM) on roots may occur through the imposition of oxidative stress on cell growth and cell division. Due to the lack of an α,β-unsaturated ketone in α-methylenecyclopentanone moiety, Gla C could not induce ROS generation and exhibited no effect on the roots, even at the highest concentration (200 μM). Therefore, the α-methylenecyclopentanone moiety in the ent-kaurene diterpenoids was presented as an essential possible active center for the phytotoxicity.     

PCI-24781 can improve in vitro and in vivo developmental capacity of pig somatic cell nuclear transfer embryos

Objective

To examine the effect of PCI-24781 (abexinostat) on the blastocyst formation rate in pig somatic cell nuclear transferred (SCNT) embryos and acetylation levels of the histone H3 lysine 9 and histone H4 lysine 12.

Results

Treatment with 0.5 nM PCI-24781 for 6 h significantly improved the development of cloned embryos, in comparison to the control group (25.3 vs. 10.5 %, P < 0.05). Furthermore, PCI-24781 treatment led to elevated acetylation of H3K9 and H4K12. TUNEL assay and Hoechst 33342 staining revealed that the percentage of apoptotic cells in blastocysts was significantly lower in PCI-24781-treated SCNT embryos than in untreated embryos. Also, PCI-24781-treated embryos were transferred into three surrogate sows, one of whom became pregnant and two fetuses developed.

Conclusion

PCI-24781 improves nuclear reprogramming and the developmental potential of pig SCNT embryos.