1,3,5‐Tri‐p‐tolyl­biuret

MoOCl₂(L_OMe) as catalyst, where L_OMe is CpCo[P(O)(OMe)₂]₃, reacts with p‐tolyl isocyanate to afford the title compound, C₂₃H₂₃N₃O₂. The structural features are the intramolecular hydrogen bond forming a six‐membered ring and a nearly planar arrangement of the biuret moiety. Each p‐tolyl phenyl ring is twisted by approximately 60–80° with respect to the others. The bond lengths N1—C22 of 1.357 (3) Å and N2—C23 of 1.333 (3) Å indicate that they are partial double bonds.     

A Rho Kinase (ROCK) Inhibitor,Y-27632, Inhibits the Dissociation-Induced Cell Death of Salivary Gland Stem Cells

Salivary gland stem cells (SGSCs) are potential cell sources for the treatment of salivary gland diseases. The control of cell survival is an essential factor for applying stem cells to regenerative medicine or stem cell-based research. The purpose of this study was to investigate the effects of the ROCK inhibitor Y-27632 on the survival of SGSCs and its underlying mechanisms. SGSCs were isolated from mouse submandibular glands and cultured in suspension. Treatment with Y-27632 restored the viability of SGSCs that was significantly decreased during isolation and the subsequent culture. Y-27632 upregulated the expression of anti-apoptotic protein BCL-2 in SGSCs and, in the apoptosis assay, significantly reduced apoptotic and necrotic cell populations. Matrigel was used to mimic the extracellular environment of an intact salivary gland. The expression of genes regulating apoptosis and the ROCK signaling pathway was significantly reduced when SGSCs were embedded in Matrigel. SGSCs cultured in Matrigel and treated with Y-27632 showed no difference in the total numbers of spheroids and expression levels of apoptosis-regulating genes. Matrigel-embedded SGSCs treated with Y-27632 increased the number of spheroids with budding structures and the expression of acinar cell-specific marker AQP5. We demonstrate the protective effects of Y-27632 against dissociation-induced apoptosis of SGSCs during their culture in vitro.     

The biological response of spermidine induced by ionization radiation

Globally, there are concerns over the risks associated with radiation exposure, so it is important to understand the biological effects of radiation exposure. Driven by the need to detect the presence of radiation exposure, biomarkers to monitor potential exposure after radiological accidents can be developed and would be extremely valuable for biological response. In this study, the behavior of spermidine as a biomarker was investigated in a C57BL/6 mouse model exposed to an acute whole-body sublethal dose of 6 Gy. The spermidine content values in serum increased for up to two days after 6 Gy irradiation. However, the enhanced spermidine content observed on day +3 in irradiated mice returned to normal levels on the subsequent five days. The result indicates that spermidine can be used as a biomarker of biological response to radiation exposure.     

Screening of anti-obesity agent from herbal mixtures

Globally, one in three of the World's adults are overweight and one in 10 is obese. By 2015, World Health Organization (WHO) estimates the number of chubby adults will balloon to 2.3 billion--Equal to the combined populations of China, Europe and the United States. The discovery of bioactive compounds from herbs is one possible way to control obesity and to prevent or reduce the risks of developing various obesity-related diseases. In this study, we screened anti-obesity agents such as methyl gallate from the herbal composition known as HemoHIM that actively inhibits lipid formation as evidenced by Oil Red O staining and triglyceride (TG) contents in 3T3-L1 adipocytes, suggesting their use as an anti-obesity agent. Furthermore, the amount of glycerol released from cells into the medium had increased by treatment of methyl gallate in a concentration-dependent manner. The present study suggests that a promising anti-obesity agent like methyl gallate might be of therapeutic interest for the treatment of obesity.     

Electrochemical performances of Li–Mn spinel synthesized from nanosized chemical manganese dioxide

Li–Mn spinel (LiMn₂O₄) is prepared from several chemical manganese dioxides (CMDs) and the electrochemical performances are compared. The CMDs are synthesized via a redox process involving the simultaneous reduction and oxidation reaction of manganese ions in starting materials to converge to MnO₂. KMnO₄ is used as an oxidizing agent and various manganese(II) salts as reducing agents in the redox process. The crystalline phase, particle size and shape, and specific surface area (SSA) of the CMDs and the Li–Mn spinels are examined. The influence of the starting manganese salts on the above properties is also investigated. The CMDs form as aggregates of nanosized particles with different crystalline phase according to the starting manganese salts. Pure Li–Mn spinel phase is obtained from the CMDs irrespective of the different crystalline phases. The charge and discharge profiles of the LiMn₂O₄ are measured and compared.     

Synthesis of dispirocyclohexadiene bisoxindole from Morita-Baylis-Hillman carbonate of isatin

6π-Electrocyclization of conjugated trienes derived in-situ from the Morita-Baylis-Hillman carbonates of N-methylisatins afforded dispirocyclohexadiene bisoxindoles in good yields. Two stereoisomers (cis and trans) were formed in almost equal amounts.     

Proton conducting grafted/crosslinked membranes prepared from poly(vinylidene fluoride‐co‐chlorotrifluoroethylene) copolymer

Poly(vinylidene fluoride‐co‐chlorotrifluoroethylene) (P(VDF‐co‐CTFE)) backbone was grafted with crosslinkable chains of poly(hydroxyl ethyl acrylate) (PHEA) and proton conducting chains of poly(styrene sulfonic acid) (PSSA) to produce amphiphilic P(VDF‐co‐CTFE)‐g‐P(HEA‐co‐SSA) graft copolymer via atom transfer radical polymerization (ATRP). Successful synthesis and microphase‐separated structure of the copolymer were confirmed by ¹H NMR, FT‐IR spectroscopy, and TEM analysis. Furthermore, this graft copolymer was thermally crosslinked with sulfosuccinic acid (SA) to produce grafted/crosslinked membranes. Ion exchange capacity (IEC) increased continuously with increasing SA contents but the water uptake increased up to 6 wt% of SA concentration, above which it decreased monotonically. The membrane also exhibited a maximum proton conductivity of 0.062 S/cm at 6 wt% of SA concentration, resulting from competitive effect between the increase of ionic groups and the degree of crosslinking. XRD patterns also revealed that the crystalline structures of P(VDF‐co‐CTFE) disrupted upon graft polymerization and crosslinking. These membranes exhibited good thermal stability at least up to 250°C, as revealed by TGA. Copyright © 2009 John Wiley & Sons, Ltd.     

Construction of a Square-wave-shaped One-dimensional Polyrotaxane Using a Preorganized L-shaped Pseudorotaxane

The construction of a square-wave-shaped one-dimensional polyrotaxane using a preorganized L-shaped [3]pseudorotaxane and metal ion is reported. A phenanthroline derivative having two N -(3-pyridylmethyl)-1,4-butanediammonium "arms" was synthesized as a preorganized L-shaped ligand. This L-shaped ligand easily forms a stable [3]pseudorotaxane incorporating cucurbituril (CB[6]). The reaction of the [3]pseudorotaxane with Ni(II) or Zn(II) ion produces a square-wave-shaped one-dimensional-polyrotaxane.