Controlled polymerization of protic ionic liquid monomer by ARGET-ATRP and TERP.

The direct synthesis of structurally well-defined protic polymeric ionic liquid (PIL) with controlled molecular weight and molecular weight distribution is examined using N,N-diethyl-N-(2-methacryloylethyl) ammonium bis(tri-fluoromethylsulfonyl)imide (DEMH-TFSI) as a monomer. Three polymerization methods, namely, atom transfer radical polymerization (ATRP), activators regenerated by electron transfer (ARGET)-ATRP, and organotellurium-mediated living radical polymerization (TERP) are employed in this study. While the polymerization by ATRP is slow and does not reach high monomer conversion that under ARGET-ATRP and TERP proceeds smoothly and affords structurally well-defined poly(DEMH-TFSI)s. TERP is especially efficient for the control and poly(DEMH-TFSI)s with low to high molecular weights (M¯(n) = 49 100-392 500) and narrow molecular weight distributions (M¯(w)/M¯(n) = 1.17-1.46) are obtained. These results represent the first example of synthesis of a structurally well-defined protic, ammonium PIL by direct polymerization of the protic ionic liquid monomer. The polymerization of N,N-diethyl-N-(2-methacryloylethyl)-N-methylammonium bis(trifluoromethylsulfonyl)imide (DEMM-TFSI), which possesses a quaternary ammonium salt, also proceeds in a highly controlled manner under TERP conditions. A diblock copolymer, polystyrene-block-poly(DEMH-TFSI), is also successfully synthesized by TERP.

Tracing whale myoglobin evolution by resurrecting ancient proteins.

Extant cetaceans, such as sperm whale, acquired the great ability to dive into the ocean depths during the evolution from their terrestrial ancestor that lived about 50 million years ago. Myoglobin (Mb) is highly concentrated in the myocytes of diving animals, in comparison with those of land animals, and is thought to play a crucial role in their adaptation as the molecular aqualung. Here, we resurrected ancestral whale Mbs, which are from the common ancestor between toothed and baleen whales (Basilosaurus), and from a further common quadrupedal ancestor between whale and hippopotamus (Pakicetus). The experimental and theoretical analyses demonstrated that whale Mb adopted two distinguished strategies to increase the protein concentration in vivo along the evolutionary history of deep sea adaptation; gaining precipitant tolerance in the early phase of the evolution, and increase of folding stability in the late phase.

A new drug delivery system targeting ileal epithelial cells induced electrogenic sodium absorption: possible promotion of intestinal adaptation.

We previously demonstrated the induction of the epithelial sodium channel, prostasin, and 11beta-hydroxysteroid dehydrogenase type 2 and activation of sodium transport mediated by those molecules in the remnant ileum after total proctocolectomy. The aims of the present study were to develop a new drug delivery system that targets ileal epithelial cells and to enhance local mineralocorticoid action without systemic effects. Orally administered D-aldosterone-containing D,L-lactide/glycolide acid copolymer microspheres are absorbed in the rat terminal ileum and released aldosterone. Blood and terminal ileal tissues were collected 2 weeks after the administration of the microspheres, and the aldosterone concentrations, mRNA, and protein expressions of the above molecules and sodium transport were evaluated. Significantly high levels of tissue aldosterone in the absence of elevated plasma levels were detected in the microspheres-treated rats. Epithelial mRNA and protein expression of the above molecules increased significantly in the microspheres-treated animals. Electrogenic sodium transport in the ileum was enhanced in the microspheres-treated rats. Aldosterone-containing microspheres successfully induced the expression of the above molecules and activated sodium transport in the ileal mucosa, both of which are essential for intestinal adaptation. Pre- and/or postoperative treatment with this drug may compensate for the excessive loss of sodium and water following proctocolectomy.

Trabecular bone response to titanium implants with a thin carbonate-containing apatite coating applied using the molecular precursor method.

PURPOSE: The influence of thin carbonate-containing apatite (CA) coating on the trabecular bone response to titanium implants was investigated. MATERIALS AND METHODS: Thin CA coatings were deposited by a new method known as the molecular precursor method. Using a precursor solution composed of an EDTA-calcium complex, a CA film was deposited on the titanium surfaces. Uncoated and CA-coated titanium were placed in the trabecular bone of the left and right femoral condyles of 16 rabbits. After implantation periods of 2, 4, 8, and 12 weeks, the bone-implant interface was evaluated histologically and histomorphometrically. RESULTS: Histologic evaluation revealed new bone formation around the uncoated and CA-coated implant surfaces after only 4 weeks of implantation. After 12 weeks, mature trabecular bone surrounded all implants. At 4 and 8 weeks of implantation, no difference existed in bone contact between uncoated and CA-coated implants. After 12 weeks of implantation, the CA-coated implant group showed a significantly higher percentage of bone contact than the uncoated implant group. DISCUSSION AND CONCLUSION: The present study demonstrated that thin CA coatings applied using the molecular precursor method showed greater bone-to-implant contact during the healing phase than uncoated controls. The results were similar to those observed with implants with calcium phosphate coatings deposited with a physical vapor deposition technique.

[Jaw evolution and function of mastication].

Gnathostomata improved the brachial cartilages of Agnahta into jaws. At the same time, such a jaw formation resulted not only in the development of eye, nose, and ear for searching foods but also in the development of brain which regulates the functions of these sense organs and mastication muscles. In this paper, we described about the muscles, mouth, tongue, and jaw which participate in mastication from a view point of morphology and molecular biology.

[Ontogeny of the jaw].

Four pairs of branchial arch appear apparently in the neck region of human embryo about 32 days after fertilization. Maxillary prominence of the first branchial arch gives rise to the maxilla and zygomatic bone etc., and mandibular prominence forms the mandible and so on. Muscles for mastication are also derived from 1st branchial arch, into which fifth cranial nerves grow from the brain. Thus, human embryo improves the 1st branchial arches into the upper and lower jaws, and forms digestive organs needed for intake, mastication, and swallowing of foods. Finally they develop the brain for integral treatment of sensory information from eyes, tongue, nose, and ears.

[Phylogeny of the jaw].

Since primary life appeared in the sea about 3.8 billion years ago, the Agnatha improved a part of the respiratory organ, or brachial arch into the jaw during the evolutionary process. The resulting Gnathostomata could catch bigger fish by using the strong jaw. In addition, they developed specific sensory organs in the head, including nose, eyes and ears for detecting position of diets, brain for treating the sensory information, and muscles for masticating foods. Such development of jaw from the brachial arch had an important meaning in the evolutional history of organisms.

Effect of thin carbonate-containing apatite (CA) coating of titanium fiber mesh on trabecular bone response.

The influence of thin carbonate-containing apatite (CA) coating on trabecular bone response to cylindrical titanium fiber mesh (porosity of 85%, pore size of 200-300 microm, 2.8 mm diameter x 6 mm length) implants was investigated. Thin CA coatings were deposited by the so-called molecular precursor method. Molecular precursor solution was obtained by adding dibutylammonium diphosphate salt to Ca-EDTA/amine ethanol solution by adjusting Ca/P = 1.67. Sintered cylindrical titanium fiber mesh was immersed into molecular precursor solution and then tempered at 600 degrees C for 2 h. The immersion and tempering process was repeated three times. An adherent thin CA film could be deposited on the inside of titanium fiber mesh. After the immersion of a CA-coated titanium fiber mesh in simulated body fluid, apatite crystals precipitated on the titanium fiber mesh. Uncoated and CA-coated titanium fiber mesh was inserted into the trabecular bone of the left and right femoral condyles of rabbits. Histological and histomorphometrical evaluation revealed a significantly greater amount of bone formation inside the porous area of the CA-coated titanium fiber mesh after 12 weeks of implantation. The present results suggested that a thin CA-coated titanium mesh has better osteoconductivity and will be useful for a three-dimensional scaffold.

Effect of calcium polycarbophil on bowel function after restorative proctocolectomy for ulcerative colitis: a randomized controlled trial.

The aim of the present study was to determine if calcium polycarbophil ameliorates diarrhea after ileal J-pouch anal anastomosis for ulcerative colitis. Twenty-one randomized patients were given either bifidobacterium (3 g/day) plus calcium polycarbophil (3 g/day), in the polycarbophil group (11 patients), or bifidobacterium (3 g/day), in the control group (10 patients), p.o. for 6 months. Anal manometry was performed and bowel function (stool frequency, stool consistency, and nighttime soiling) was assessed via a questionnaire before and 1, 3, and 6 months after drug administration. Eight patients were deemed eligible in each group; five patients were excluded from the study, including two patients whose stool consistency was too firm and who experienced difficulty in defecating attributed to polycarbophil. Anal manometry and stool consistency did not change with time and did not differ between the polycarbophil and the control groups. Stool frequency decreased with time in both groups and did not differ between the groups. Nighttime soiling improved with time in the polycarbophil group but did not change in the control subjects. These results suggest that polycarbophil might be able to improve nighttime soiling without obviously affecting stool frequency and consistency after ileal J-pouch anal anastomosis for ulcerative colitis.