Size, shape, and flexibility of micelles of octaoxyethylene tetradecyl C(14)E(8), hexadecyl C(16)E(8), and octadecyl C(18)E(8) ethers in dilute aqueous solutions were determined at finite surfactant concentrations c by static light scattering (SLS) and dynamic light scattering experiments at several temperatures T below the critical points. The SLS results were successfully analyzed with the aid of the thermodynamic theory formulated with wormlike spherocylinder model for SLS of micelle solutions. The analysis yielded the molar mass M(w) of the micelles as a function of c and the cross-sectional diameter d. The hydrodynamic radius R(H) and the radius of gyration S(2)(1/2) of the micelles as functions of M(w) were found to be also well-described by the corresponding theories for the wormlike spherocylinder or wormlike chain models. The results of the stiffness parameter lambda(-1) have revealed that the micelles are far from rigid rods but rather stiff compared with typical flexible polymers and they grow in size with increasing T to greater length for longer hydrophobic chains, i.e., alkyl groups of the surfactants. As the alkyl group becomes longer, the d value increased, while the spacings s between adjacent hexaoxyethylene chains on the micellar surface were found to remain substantially constant.

Protein kinase C (PKC) is widely recognized as a therapeutic target in intractable diseases such as cancer, Alzheimer's disease (AD), and acquired immune deficiency syndrome (AIDS). While inhibition of PKC is a general therapeutic strategy for the treatment of cancer, PKC activators are potential therapeutic agents for AD and AIDS. However, concerns have been raised about their therapeutic use since PKC activators such as phorbol esters exhibit potent tumor-promoting activities. Naturally occurring bryostatin 1 (bryo-1), prostratin, and 12-deoxyphorbol 13-phenylacetate (DPP) are fascinating PKC activators without tumor-promoting activities. Bryo-1 is currently in clinical trials for the treatment of cancer and is also effective against AD. Prostratin and DPP are attractive candidates for the adjunctive treatment of human immunodeficiency virus (HIV) infection. However, their limited availability from natural sources and synthetic complexity have hampered further development as therapeutic agents. We report here easy access (22 steps) to a simple analogue (1) of the tumor-promoting aplysiatoxin (ATX) as a novel PKC activator with anticancer and anti-tumor-promoting activities. Anticancer activities of 1 against several human cancer cell lines were comparable to those of bryo-1. Moreover, 1 as well as bryo-1 significantly inhibited the Epstein-Barr virus early antigen (EBV-EA) induction by the tumor promoter 12-O-tetradecanoylphorbol 13-acetate (TPA), whereas ATX strongly induced EBV-EA. This inhibitory effect is characteristic of antitumor promoters. Compound 1 as well as bryo-1 displayed significant binding and activation of PKCdelta and induced its translocation to the nuclear membrane in CHO-K1 cells. This study provides a synthetically accessible PKC activator with bryo-1-like activities, which could be another therapeutic lead for cancer, AD, and AIDS.

The locations of the stacking faults in -form single crystals of syndiotactic polystyrene, which were grown isothermally from a dilute solution at temperatures ranging from 150 to 210°C, were identified in high-resolution and dark-field (DF) images taken by transmission electron microscopy. The shift or kink of the (210) lattice fringes, which shows the position of the fault, was directly detected in the high-resolution images. DF images taken using several reflections exhibited irregularly spaced striations parallel to the b-axis. Computer simulation of DF images based on the structural model of the stacking fault well supported the view that each striation corresponds to the position of the fault. The striations extended continuously and were very long, and accordingly, it was proposed that the stacking fault influences the attachment of a new polymer stem onto the lateral growth face which is not parallel to the bc-plane, resulting in irregular fold-surfaces of the single crystals.