Genistein inhibits phorbol ester-induced NF-κB transcriptional activity and COX-2 expression by blocking the phosphorylation of p65/RelA in human mammary epithelial cells.

Genistein, an isoflavone present in soy products, has chemopreventive effects on mammary carcinogenesis. In the present study, we have investigated the effects of genistein on phorbol ester-induced expression of cyclooxygenase-2 (COX-2) that plays an important role in the pathophysiology of inflammation-associated carcinogenesis. Pretreatment of cultured human breast epithelial (MCF10A) cells with genistein reduced COX-2 expression induced by 12-O-tetradecanoylphorbol-13-acetate (TPA).

Walking motion of an overdamped active particle in a ratchet potential.

An active particle can convert its internal energy into mechanical work. We study a generalized energy-depot model of an overdamped active particle in a ratchet potential. Using well-known biological parameters for kinesin-1 and modeling ATP influx as a pulsed energy supply, we apply our model to the molecular motor system.

Non-random mating involving inheritance of social status.

We propose a unified theoretical scheme to calculate genotype frequencies of polymorphic populations with biological and social inheritance. This scheme is used to simulate the effects of social non-random mating on the population's evolution in the general situation of multiple biological gene loci and allele inheritance with natural selection and mutation. We study the case of hemophilia in several diverse situations when there exists non-random mating due to inheritance of social status.

Collective behaviors of two-component swarms.

We present a particle-based simulation study on two-component swarms where there exist two different types of groups in a swarm. Effects of different parameters between the two groups are studied systematically based on Langevin's equation. It is shown that the mass difference can introduce a protective behavior for the lighter members of the swarm in a vortex state.

Polymerizable ion-pair amphiphile that has a polymerizable group at cationic ammonium chain.

Polymerizable ion-pair amphiphile (PIPA) that has a polymerizable lipoyl group on cationic ammonium chain was prepared to compare the advantage of ion-pair form with the conventional polymerizable ammonium surfactant in the points of stability of vesicle and permeation properties. PIPA introduced in this paper, compared to previously reported one with polymerizable group on anionic chain side, showed similar vesicle stability in addition to high encapsulation efficiency and resistance to disruption by SDS or Triton X-100. Reasons for such high encapsulation and low permeability of the PIPA vesicle are investigated and the possible applications are briefly discussed.

Polymerized ion pair amphiphile vesicles with pH-sensitive transformation and controlled release property.

Ion pair amphiphiles (IPA) composed of one proton-deionizable single or double alkyl chain ammonium surfactant and one anionic carboxylate surfactant with polymerizable dithiolane ring are prepared to develop polymerized microcapsules that can recognize pH change and transform itself under basic condition, thus releasing encapsulated materials at the desired point. Combination of pH-sensitivity and polymeric solid structure, if fully developed, endows the IPA vesicle with smart function that is highly valuable in drug delivery application. Reasons for such high pH-sensitive vesicle transformation are sought from combined physical properties such as turbidity, zeta potential, surface tension, and release rate of marker through the vesicle membrane.

Fractional populations in multiple gene inheritance.

Motivation: With complete knowledge of the human genome sequence, one of the most interesting tasks remaining is to understand the functions of individual genes and how they communicate. Using the information about genes (locus, allele, mutation rate, fitness, etc.), we attempt to explain population demographic data.