The preparation and validation of chitosan tablets that rapidly disperse and disintegrate as an oral adsorbent in the treatment of lifestyle-related diseases.

A carrier and an oral absorbent for the treatment of chronic diseases in the form of a tablet was prepared from granulated chitosan (G-CS) particles. The resulting tablet was highly dispersible and disintegrated rapidly (< 30 s) in aqueous media. The non-granulated chitosan (N-CS) powder partially crystallized (2θ = 12-15° and 20°) during wet granulation to give G-CS crystalline particles. The rate of penetration of water into G-CS aggregates was markedly faster than that for N-CS aggregates, as evidenced by the ease of disintegration of the tablets. The rapid disintegration and dispersion of the tablets in vivo was confirmed by MRI measurements after the oral administration of the both tablets to rats. Some ureic toxins were adsorbed more strongly to G-CS tablets than on N-CS tablets. The results suggest that G-CS tablets have great potential for use as a fast disintegrating carrier and as an oral adsorbent in lifestyle-related diseases.

Effect of Different Silage Storing Conditions on the Oxygen Concentration in the Silo and Fermentation Quality of Rice.

We investigated the effects of different silage storing conditions on the oxygen concentration in the silo and fermentation quality of rice (Oryza sativa L.). Forage rice was ensiled in bottles (with or without space at the bottlemouth, with solid or pinhole cap, and with oxygen scavenger, ethanol transpiration agent, oxygen scavenger and ethanol transpiration agent, or no adjuvant) and stored for 57 days. The oxygen concentration decreased with the addition of the oxygen scavenger and increased with that of the ethanol transpiration agent. The oxygen scavenger facilitated silage fermentation and fungus generation, whereas the ethanol transpiration agent suppressed silage fermentation and fungus generation. However, the combined use of the oxygen scavenger and ethanol transpiration agent facilitated silage fermentation and also suppressed fungus generation. Overall, this study revealed the negative effects of oxygen on the internal silo and the positive effects of the combined use of the oxygen scavenger and ethanol transpiration agent on silage fermentation quality.

α-Lipoic acid suppresses migration and invasion via downregulation of cell surface ß1-integrin expression in bladder cancer cells.

Our previous study showed α-lipoic acid (LA) downregulated cell surface ß1-integrin expression of v-H-ras-transformed derivative of rat fibroblast with amelioration of their malignant phenotype. Here, we evaluated the ameliorating effect of LA on the malignant characters in H-ras-transformed bladder cancer cells. H-ras mutated bladder cancer line, T24 cells were incubated with LA to evaluate the inhibitory effect on proliferation, migration, invasion and ß1-integrin expression. Fluorescence staining of F-actin and western blotting analyses of the related signaling pathways were also performed. LA inhibited the proliferation of T24 cells. Cell adhesion to collagen IV and fibronectin was strikingly inhibited by LA treatment accompanied by downregulation of cell surface but not whole cell ß1-integrin expression. LA clearly inhibited cell migration and invasion of T24 cells, which were mimicked by extracellular signal-regulated kinase (ERK) and Akt pathway inhibition. Actually, LA significantly downregulated the phosphorylated ERK and Akt levels. Moreover, LA downregulated phosphorylated focal adhesion kinase level with disappearance of stress fiber formation. Finally, although LA induced the internalization of cell surface ß1-integrin, disruption of the raft did not affect the action of LA. Taken together, LA is a promising agent to improve malignant character of bladder cancer cells through regulation of cellular ß1-integrin localization.

Selective inhibition by apocynin of the proliferation and adhesion to fibronectin of v-H-ras-transformed 3Y1 cells.

We determined the effects of apocynin, a representative inhibitor of NADPH oxidase, on the proliferative and adhesive properties of 3Y1 rat fibroblasts and the 3Y1 v-H-ras-transformed derivative, HR-3Y1-2. Apocynin inhibited the proliferation of HR-3Y1-2 but not 3Y1 cells at 10 µM and 100 µM. Apocynin also decreased the intracellular reactive oxygen species (ROS) level in HR-3Y1-2 but not 3Y1 cells. We also evaluated the effects of apocynin on cell adhesion to fibronectin and found decreased adhesion of HR-3Y1-2 cells to fibronectin-coated plates. Our results indicate that apocynin selectively down-regulated ß1-integrin cell surface expression on the HR-3Y1-2 cells. It also inhibited the migration and invasion of these cells. These data suggest that reducing the production of NADPH oxidase-mediated ROS could be an effective means for ameliorating the abnormal growth, adhesion and motility of v-H-ras-transformed cells.

Alpha lipoic acid selectively inhibits proliferation and adhesion to fibronectin of v-H-ras-transformed 3Y1 cells.

Here, we focused on the effects of racemic α-lipoic acid on proliferation and adhesion properties of 3Y1 rat fibroblasts and the v-H-ras-transformed derivative, HR-3Y1-2 cells. Racemic α-lipoic acid inhibited proliferation of HR-3Y1-2 but not 3Y1 cells at 0.3 and 1.0 mM. R-(+)-α-lipoic acid also inhibited proliferation of HR-3Y1-2 cells equivalent to that of racemic α-lipoic acid. In addition, racemic α-lipoic acid decreased intracellular reactive oxygen species levels in HR-3Y1 cells but not 3Y1 cells. Next, we evaluated the effects of racemic α-lipoic acid on cell adhesion to fibronectin. The results indicated that racemic α-lipoic acid decreased adhesive ability of HR-3Y1-2 cells to fibronectin-coated plates. As blocking antibody experiment revealed that ß1-integrin plays a key role in cell adhesion in this experimental system, the effects of racemic α-lipoic acid on the expression of ß1-integrin were examined. The results indicated that racemic α-lipoic acid selectively downregulated the expression of cell surface ß1-integrin expression in HR-3Y1-2 cells. Intriguingly, exogenous hydrogen peroxide upregulated cell surface ß1-integrin expression in 3Y1 cells. Taken together, these data suggest that reduction of intracellular reactive oxygen species levels by α-lipoic acid could be an effective means of ameliorating abnormal growth and adhesive properties in v-H-ras transformed cells.

Significance of kinetic degrees of freedom in operation of the actomyosin motor.

The actomyosin motor as a principal functional component of cell motility is highly coordinated in regulating the participating molecular components. At the same time, it has to be flexible and plastic enough to accommodate itself to a wide variety of operational conditions. We prepared two different types of actomyosin systems. One is a natural intact actomyosin system with no artificial constraint on the kinetic degrees of freedom of the actin filaments, and the other is a regulated one with actin filaments supplemented by intra- and intermolecular crosslinking to suppress the kinetic degrees of freedom to a certain extent. Crosslinked actomyosin systems were found to remain almost insensitive to calcium regulation even when intact troponin-tropomyosin regulatory component was incorporated. Both the ATPase and the motile activities of the actin filaments sliding on myosin molecules were markedly lowered by the crosslinking. In contrast, once the crosslinking was cleaved, both properties returned to the normal as with intact actomyosin systems.

Developmental stability and adaptive variability of male genitalia in sexually dimorphic beetles.

Animal genitalia often show distinct developmental and evolutionary relationships with other parts of the body. Morphological observations of 29 sexually dimorphic and monomorphic beetle species in 16 genera of families Scarabaeidae and Lucanidae, Coleoptera, in 53 locations revealed that male genitalia size was consistently and distinctly less variable than that of other body parts within the same population, while it differentiated more readily among different populations than other body parts. The most noticeable genitalia size differentiation occurred in populations that coexisted with morphologically and ecologically similar congeneric species. Such differentiation may indicate selection for reproductive isolation. These characteristics of genitalia morphology may have been instrumental in generating the speciation pattern seen in most beetles.

Character displacement in giant rhinoceros beetles.

I quantitatively analyzed male morphology of two closely related rhinoceros beetles species (Chalcosoma caucasus F. and Chalcosoma atlas L.) in 12 allopatric and seven sympatric locations throughout Southeast Asia. The qualitative features and the magnitude of intraspecific variation of each species were unaltered between allopatric and sympatric locations. Across allopatric locations, body size, horn size, dimorphic dimension, and genitalia size nearly completely overlapped between C. caucasus and C. atlas. Yet, in all sympatric locations, the differences between the two species in these characters were highly significant. While the enlarged difference between the two species in body size in sympatry could be attributed to habitat differentiation, that in genitalia size far exceeded what was expected from the general body-size displacement. These results indicate that morphological character displacement in sympatry was most complete in sexual organs. This may account for the process of existing species conserving themselves as integrated units by avoiding interspecific competition and enhancing reproductive isolation.