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Marugame, Japan

Oosaka K.,Fushimi Pharmaceutical Co. | Tokuda M.,Kagawa University | Furukawa N.,Kawasaki University of Medical Welfare
World Journal of Gastroenterology | Year: 2014

AIM: To examine the effect of intra-gastric triacetin on both upper gastrointestinal motility and proximal gastric tone in conscious dogs. METHODS: Three beagle dogs under sedation were surgically implanted with gastrocutaneous fistula in the gastric body and force transducers in the gastric antrum and duodenum. Beginning at week-2 after insertion, the animals were either fasted for 24 h or fed a liquid meal 2-3 h before the experiment. With the animals fully conscious, a polyethylene bag was inserted into the proximal stomach through the gastrocutaneous fistula, followed by 15 min of air inflation (minimal distending pressure of +2 mmHg) and then 20 mL of a low-, mid- or high-concentration triacetin solution (0.5%, 1.0% and 2.0%) or warm water (vehicle control). The proximal stomach receptive volume and gastric antral and duodenal contractions were measured over 10 min. The experiment was repeated twice per week over several months, with each animal receiving at least one infusion of the various triacetin solutions and the vehicle at different times. Intergroup differences were assessed by ANOVA and Bonferroni-Dunn post-hoc testing. RESULTS: Intra-gastric infusion of mid- and high-concentration triacetin induced an increase in the proximal stomach receptive volume, and the average increase induced by the high-concentration at 0-4 min after infusion was significantly greater than that induced by the vehicle control (62.4 ± 9.8 vs 18.4 ± 4.7, p < 0.01). The mid- and high-concentration triacetin also produced a temporary inhibition of the gastric antral contractions at 2 min after infusions; however, only the fasted group showed triacetin-induced antral contractile inhibition that was significantly greater than that in the vehicle control group (p < 0.05). In addition, only the fasted group showed a high-concentration triacetininduced increase in duodenal contractions at 9-10 min that was significantly different from that in the vehicle control group (p < 0.05). CONCLUSION: Intra-gastric infusion of 1.0%-2.0% triacetin delays gastric emptying by increasing proximal stomach receptive volume, temporarily inhibiting gastric antral contractions and facilitating duodenal contractions. © 2014 Baishideng Publishing Group Co., Limited. All rights reserved.

Weikel A.L.,Pennsylvania State University | Owens S.G.,Pennsylvania State University | Fushimi T.,Fushimi Pharmaceutical Co. | Allcock H.R.,Pennsylvania State University
Macromolecules | Year: 2010

The preparation of phosphazenes that possess reversible cross-linking groups to control mechanical stability and hydrolysis has been accomplished using cysteine and methionine amino acid side groups. Small molecule models and linear polymeric phosphazenes that contain methionine ethyl ester and cysteine ethyl disulfide ethyl ester side groups were synthesized. Protection of the free thiol groups was carried out to circumvent unwanted cross-linking of the phosphazenes through the cysteine ethyl ester N- and S-termini. Cyclic trimeric cysteine ethyl disulfide ethyl ester model compounds were deprotected by S - S bond cleavage using β-mercaptoethanol, dithiothreitol (DTT), and zinc in aqueous hydrochloric acid. For the high polymeric derivatives, the extent of S - S bond cleavage varied depending on the deprotection method used. With the exception of the Zn/HCl method, the resultant deprotected polymers were soluble in common organic solvents and underwent minimal chain cleavage during the reaction sequence. The protected or deprotected high polymers are candidates for reversible cross-linking in drug delivery systems and for cross-link stabilization of tissue engineering scaffolds. © 2010 American Chemical Society.

Asano R.,Fushimi Pharmaceutical Co. | Nagami A.,Prefectural University of Hiroshima | Fukumoto Y.,Prefectural University of Hiroshima | Yazama F.,Prefectural University of Hiroshima | And 3 more authors.
Bioorganic and Medicinal Chemistry | Year: 2013

Three new water-soluble chlorin derivatives 3, 5 and 8 for potential use as photosensitizers in photodynamic therapy (PDT) for cancer were synthesized from photoprotoporphyrin IX dimethyl ester (1). The in vivo biodistribution and clearance of chlorin derivatives 3, 5 and 8 were investigated in tumor-bearing mice. Iminodiacetic acid derivative 8 showed the greatest tumor-selective accumulation among the new chlorin derivatives with maximum accumulation in tumor tissue at 3 h after intravenous injection and rapid clearance from normal tissues within 24 h after injection. The in vivo therapeutic efficacy of PDT using 8 was evaluated by measuring tumor growth rates in tumor-bearing mice with 660 nm light-emitting diode irradiation at 3 h after injection of 8. Tumor growth was significantly inhibited by PDT using 8. These results indicate that iminodiacetic acid derivative 8 is useful as a new photosensitizer to overcome the disadvantages of photosensitizers that are currently in clinical use. © 2013 Elsevier Ltd. All rights reserved.

Lee D.K.Y.,Pennsylvania State University | Jackson A.-M.S.,Pennsylvania State University | Fushimi T.,Fushimi Pharmaceutical Co. | Yennawar H.,Pennsylvania State University | Allcock H.R.,Pennsylvania State University
Dalton Transactions | Year: 2010

Two novel cyclic phosphazenes with asymmetric spiro rings were synthesized via reactions of hexachlorocyclotriphosphazene with chiral amino alcohol residues. The reactions showed preferential formation of the cis isomer possibly due to the delocalization of the lone pair electrons of the spirocylic nitrogen, which reduces its ability to solvate protons. Crystals of these phosphazenes were analyzed by X-ray crystallography which confirmed the formation of cis isomers and showed their ability to include guest molecules within the crystal lattices. The selective inclusion of epoxides by one of the phosphazenes was an effective method for the separation of thermally sensitive guest molecules. © 2010 The Royal Society of Chemistry.

Fushimi T.,Fushimi Pharmaceutical Co. | Allcock H.R.,Pennsylvania State University
Dalton Transactions | Year: 2010

Novel cyclotriphosphazenes with sulfur-containing spirocyclic side groups were synthesized and polymerized to cyclomatrix materials for potential optical applications. The cyclotriphosphazenes were designed to give a high content of the phosphazene unit and sulfur atoms, as well as the capability for polymerization by ring- opening of the side groups. The chemical structures of the monomers were confirmed by NMR spectrometry, mass spectrometry, and single-crystal X-ray diffraction. Transparent solids were obtained by thermal bulk polymerization, and these were analyzed by the use of DSC, infrared spectroscopy, and mass spectrometry. One of the resultant cyclomatrix polyphosphazenes had a refractive index at 589 nm of 1.6465 and an Abbe number of 39. The contribution of the phosphazene unit to the refractive index is discussed. © 2010 The Royal Society of Chemistry.

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