Orderly arranged NLO materials on exfoliated layeredtemplates based on dendrons with alternating moietiesat the periphery†

Nonlinear optical dendrons with alternating terminal groups of the stearyl group (C18) and chromophorewere prepared through a convergent approach. These chromophore-containing dendrons were used asthe intercalating agents for montmorillonite via an ion-exchange process. An orderly exfoliatedmorphology is obtained by mixing the dendritic structure intercalated layered silicates with a polyimide.As a result, optical nonlinearity, i.e. the Pockels effect was observed for these nanocomposites withoutresorting to the poling process. EO coefficients of 9–22 pm V 1 were achieved despite that relativelylow NLO densities were present in the nanocomposites, particularly for the samples comprising thedendrons with alternating moieties. In addition, the hedging effects of the stearyl group on the selfalignmentbehavior, electro-optical (EO) coefficient and temporal stability of the dendron-intercalatedmontmorillonite/polyimide nanocomposites were also investigated

Male Germ Cell-Specific RNA Binding Protein RBMY: A New Oncogene Explaining Male Predominance in Liver Cancer

Male gender is a risk factor for the development of hepatocellular carcinoma (HCC) but the mechanisms are not fully understood. The RNA binding motif gene on the Y chromosome (RBMY), encoding a male germ cell-specific RNA splicing regulator during spermatogenesis, is aberrantly activated in human male liver cancers. This study investigated the in vitro oncogenic effect and the possible mechanism of RBMY in human hepatoma cell line HepG2 and its in vivo effect with regards to the livers of human and transgenic mice. RBMY expression in HepG2 cells was knocked down by RNA interference and the cancer cell phenotype was characterized by soft-agar colony formation and sensitivity to hydrogen-peroxide-induced apoptosis. The results revealed that RBMY knockdown reduced the transformation and anti-apoptotic efficiency of HepG2 cells. The expression of RBMY, androgen receptor (AR) and its inhibitory variant AR45, AR-targeted genes insulin-like growth factor 1 (IGF-1) and insulin-like growth factor binding protein 3 (IGFBP-3) was analyzed by quantitative RT-PCR. Up-regulation of AR45 variant and reduction of IGF-1 and IGFBP-3 expression was only detected in RBMY knockdown cells. Moreover, RBMY positive human male HCC expressed lower level of AR45 as compared to RBMY negative HCC tissues. The oncogenic properties of RBMY were further assessed in a transgenic mouse model. Liver-specific RBMY transgenic mice developed hepatic pre-cancerous lesions, adenoma, and HCC. RBMY also accelerated chemical carcinogen-induced hepatocarcinogenesis in transgenic mice. Collectively, these findings suggest that Y chromosome-specific RBMY is likely involved in the regulation of androgen receptor activity and contributes to male predominance of HCC

Urinary levels of organophosphate flame retardants metabolites in a young population from Southern Taiwan and potential health effects

BackgroundOrganophosphate flame retardants (OPFRs) are widely distributed in the environment and their metabolites are observed in urine, but little is known regarding OPFRs in a broad-spectrum young population from newborns to those aged 18 years.ObjectivesInvestigate urinary levels of OPFRs and OPFR metabolites in Taiwanese infants, young children, schoolchildren, and adolescents within the general population.MethodsDifferent age groups of subjects (n=136) were recruited from southern Taiwan to detect 10 OPFR metabolites in urine samples. Associations between urinary OPFRs and their corresponding metabolites and potential health status were also examined.ResultsThe mean level of urinary Σ10 OPFR in this broad-spectrum young population is 2.25 μg/L (standard deviation (SD) of 1.91 μg/L). Σ10 OPFR metabolites in urine are 3.25 ± 2.84, 3.06 ± 2.21, 1.75 ± 1.10, and 2.32 ± 2.29 μg/L in the age groups comprising of newborns, 1-5 year-olds, 6-10 year-olds, and 11-18 year-olds, respectively, and borderline significant differences were found in the different age groups (p=0.125). The OPFR metabolites of TCEP, BCEP, DPHP, TBEP, DBEP, and BDCPP predominate in urine and comprise more than 90% of the total. TBEP was highly correlated with DBEP in this population (r=0.845, p<0.001). The estimated daily intake (EDI) of Σ5OPFRs (TDCPP, TCEP, TBEP, TNBP, and TPHP) was 2,230, 461, 130, and 184 ng/kg bw/day for newborns, 1-5 yr children, 6-10 yr children, and 11-17 yr adolescents, respectively. The EDI of Σ5OPFRs for newborns was 4.83-17.2 times higher than the other age groups. Urinary OPFR metabolites are significantly correlated with birth length and chest circumference in newborns.ConclusionTo our knowledge, this is the first investigation of urinary OPFR metabolite levels in a broad-spectrum young population. There tended to be higher exposure rates in both newborns and pre-schoolers, though little is known about their exposure levels or factors leading to exposure in the young population. Further studies should clarify the exposure levels and factor relationships

Isolation and Characterization of Novel Murine Epiphysis Derived Mesenchymal Stem Cells

BACKGROUND: While bone marrow (BM) is a rich source of mesenchymal stem cells (MSCs), previous studies have shown that MSCs derived from mouse BM (BMMSCs) were difficult to manipulate as compared to MSCs derived from other species. The objective of this study was to find an alternative murine MSCs source that could provide sufficient MSCs. METHODOLOGY/PRINCIPAL FINDINGS: In this study, we described a novel type of MSCs that migrates directly from the mouse epiphysis in culture. Epiphysis-derived MSCs (EMSCs) could be extensively expanded in plastic adherent culture, and they had a greater ability for clonogenic formation and cell proliferation than BMMSCs. Under specific induction conditions, EMSCs demonstrated multipotency through their ability to differentiate into adipocytes, osteocytes and chondrocytes. Immunophenotypic analysis demonstrated that EMSCs were positive for CD29, CD44, CD73, CD105, CD166, Sca-1 and SSEA-4, while negative for CD11b, CD31, CD34 and CD45. Notably, EMSCs did not express major histocompatibility complex class I (MHC I) or MHC II under our culture system. EMSCs also successfully suppressed the proliferation of splenocytes triggered by concanavalin A (Con A) or allogeneic splenocytes, and decreased the expression of IL-1, IL-6 and TNF-α in Con A-stimulated splenocytes suggesting their anti-inflammatory properties. Moreover, EMSCs enhanced fracture repair, ameliorated necrosis in ischemic skin flap, and improved blood perfusion in hindlimb ischemia in the in vivo experiments. CONCLUSIONS/SIGNIFICANCES: These results indicate that EMSCs, a new type of MSCs established by our simple isolation method, are a preferable alternative for mice MSCs due to their better growth and differentiation potentialities

Immunomodulating Activity of <em>Nymphaea rubra </em>Roxb. Extracts: Activation of Rat Dendritic Cells and Improvement of the TH1 Immune Response

Polysaccharides play a key role in enhancing immune function and facilitating cellular communication. Here, we purified <em>Nymphaea rubra </em>Roxb<em>. </em>polysaccharides (NR-PS) by treating them with pullulanase. They were then cultured with immature dendritic cells (DCs) derived from rat bone marrow hematopoietic cells (BMHCs). After treatment with bioactive NR-PS with a degree of polymerization (DP) value of 359.8, we found that the DCs underwent morphological changes indicative of activation. CD80/86 (87.16% ± 8.49%) and MHC class II (52.01% ± 10.11%) expression levels were significantly up-regulated by this treatment compared to the controls (65.45% ± 0.97% and 34.87% ± 1.96%). In parallel, endocytosis was also reduced (167.94% ± 60.59%) after treatment with 25 μg/mL of NR-PS as measured by the medium fluorescence intensity compared to the control (261.67% ± 47.26%). Furthermore, the DCs after treatment with 25 μg/mL NR-PS showed increased IL-12 (102.09 ± 10.16 to 258.78 ± 25.26 pg/mL) and IFN-γ (11.76 ± 0.11 to 15.51 ± 1.66 pg/mL) secretion together with reduced IL-10 secretion (30.75 ± 3.35 to 15.37 ± 2.35 pg/mL), which indicates a T<sub>H</sub>1 immune response. In conclusion, NR-PS exhibits stimulatory effects on rat DCs and promotes the secretion of T<sub>H</sub>1 cytokines. Taken together, our studies are the first to show that NR-PS is an immunomodulator affecting the maturation and functioning of DCs