巻号一覧
20 巻 (1995)
- 6 号 p. 372-
- 5 号 p. 302-
- 4 号 p. 246-
- 3 号 p. 156-
- 2 号 p. 92-
- 1 号 p. 2-
20 巻, 4 号
選択された号の論文の8件中1～8を表示しています
- |<
- <
- 1
- >
- >|
-
宮嶋 孝一郎1995 年 20 巻 4 号 p. 246-254
発行日: 1995/07/01
公開日: 2011/03/04
ジャーナル フリーModified natural and synthetic polymers and phospholipids have been studied as membrane materials in medical and pharmaceutical fields. Chitin prepared from the carapace of carb and shrimp is biodegradable polymer of acetylglucosamine and easily forms a film and fiber from solution. The chitin film protects from an attack of bacteria, when covered on the wounded site and accelerates the recovery. Polymer membranes have been used as materials of microcapsules containing drugs inside, through oral, subcantaneous and intramuscular administrations. These microcapsules administred orally are capable to release drugs at tageting organ in time-dependent manner. Biodegradable polymer microcapsule implanted in muscle through injection, releases drugs for over 4 weeks at a constant rate.
Biodegradable and biocompatible phospholipids has been applied for the preparations of intraveneous administrations as a liposome and a microsphere. Liposomes and microspheres accumlate generally in reticuloendotherial system (RES). Recently RES-avoiding liposome has been developed by the modification of liposomal surface with polyethylene glycol and applied for an artificial red blood cell with undated hemoglobin. Lipid microsphere containing prostaglandin E1 and anti-inflammation drug had been applied for the cure of inflammation deseases, because the inflammation sites are macropharge-rich.抄録全体を表示PDF形式でダウンロード (983K) -
鶴谷 良一, 吉村 昌也, 谷本 信行, 木船 紘爾1995 年 20 巻 4 号 p. 255-262
発行日: 1995/07/01
公開日: 2011/03/04
ジャーナル フリーChitin is a unique polysaccharide which has aminoacetyl group. In recent years, it has been reported in several papers that Chitin has the interesting biological activities.
We have developed a chitin film which is used for a wound dressing. In this study, it has found that chitin has a good biocompatibility which is one of the most desireble properties for biomaterials.
Animal and clinical tests have proved the usefulness of the chitin film for the wound dressing, especially in the view of the acceleration of the wound healing, the pain reduction and the regeneration of smooth epidermis.
It has been observed by the immunohistochemical study that chitin induces lysozyme and shows both low antigenisity and imflamatory reaction.抄録全体を表示PDF形式でダウンロード (1827K) -
木村 在久, 上田 聡, 村田 三郎, 徳永 雄二, 秦 武久1995 年 20 巻 4 号 p. 263-269
発行日: 1995/07/01
公開日: 2011/03/04
ジャーナル フリーThere has been a continuous interest in the development of controlled drug release systems to acornplish therapeutical optimization of drugs. In addition, recent advances in chronopharmacology indicate that the pharmacokinetics of some drugs show circadian rhythm. Both pharmacological and toxicological effects of such drugs are dependent on the time of day when the drug is administered.
Under these considerations, we have developed a novel controlled-release system called Time-Controlled Explosion System (TES) that can provide any desired release profile. TES has a four-layered spherical structure, which consists of core, drug layer, swelling agent (low-substituted hydroxypropylcellulose, L-HPC) layer and water insoluble polymer (ethylcellulose, EC) membrane. TES is characterized by a rapid drug release with a precisely programmed lag time ; i.e. expansion of the swelling agent by water penetrating through the outer membrane, destruction of the membrane by stress due to swelling force and subsequent rapid drug release. Lag time was controlled by the thickness of the outer EC membrane ; thus, a combination of TES particles possessing different lag times could offer any desired release profile of the drug.
After TES with different in vitro lag times were orally administrated to dogs and healthy volunteers, plasma drug concentration was monitored. There existed a good correlation between in vitro and in vivo lag time. And the in vivo release profile corresponded with the in vitro one. In these results, the drug absorption profile of TES can be mirrored by in vitro drug release behavior because TES can release the drug after the membrane destruction in the in vivo conditions in the same way as in vitro.抄録全体を表示PDF形式でダウンロード (787K) -
部谷 敏郎, 岡田 弘晃, 小川 泰亮1995 年 20 巻 4 号 p. 270-275
発行日: 1995/07/01
公開日: 2011/03/04
ジャーナル フリーThe preparation of injectable sustained release microspheres of thyrotropin releasing hormone (TRH) was investigated. The drug was encapsulated in biodegradable copoly (dl-lactic/glycolic acid) (PLGA) using an in-water drying method through a W/O/W emulsion. The microspheres with a small initial burst followed by a zero-order sustained release could be prepared in spite of the high water solubility of the drug. The electrostatic interaction between the basic functional group of TRH and the carboxylic end terminal of PLGA was found to be the predominating factors in preparing the microspheres with a small initial burst followed by a zero-order sustained release. The drug release rate from the microspheres was mainly dominated by the degradation of PLGA. The release rate was also influenced by the osmolarity yielded inside the microspheres. After the s.c. injection of the micropsheres, steadystate plasma levels were observed following a transient increase of the plasma level due to an initial burst. This method is applicable to the microencapsulation of other water-soluble basic peptides in PLGA.抄録全体を表示PDF形式でダウンロード (817K) -
上田 泰生, 松田 寛1995 年 20 巻 4 号 p. 276-281
発行日: 1995/07/01
公開日: 2011/03/04
ジャーナル フリーAlprostadil (PGE1) shows potent vasodilating effect and anti-platelet effect and its clinical usefulness has been confirmed. But it is known that plasma half life of PGE1 is very short because it is easily metabolized very rapidly mainly in lung. It is considered that avoiding the rapid enzymatic attack is important point to make a effective formulation of PGE1. We studied two liposomal formulations of PGE1, liposome with pH gradient and liposome composed of hydrogenated egg phophatidylcholine (H-EPC). Both liposomal preparations showed higher plasma concentration of PGE1 than PGE1 solution when these preparations were administered intravenously to rats. Pharmacological effect of liposomal preparations was also stronger than that of PGE1 solution. The effect was in proportion to plasma concentration of PGE1. Liposomal PGE1 with pH gradient was presumed to be stable for 2 years below 10° after lyophilization. It is concluded that these liposomal preparations of PGE1 could be promising candidates for human use.抄録全体を表示PDF形式でダウンロード (681K) -
後藤 博, 浅川 芳和, 筒井 洋治, 大木 紀子, 木村 哲寛, 緒方 嘉貴, 上谷 利治1995 年 20 巻 4 号 p. 282-286
発行日: 1995/07/01
公開日: 2011/03/04
ジャーナル フリーWe have developed and evaluated the liposome encapsulated high-concentrated (>45%) stroma free hemoglobin (SFH) : Neo Red Cell (NRC). SFH was encapsulated together with inositol-hexaphosphate (as an allosteric effector), coenzyme and substrates for reducing metHb back to oxyHb in liposomes. The NRC was subsequently coated with polyethylene glycol bound phosphatidylethanolamine as surface modifier to prevent aggregation of NRC in plasma. The oxygen affinity and the transport efficiency of NRC could be controlled as equal or more than those of the erythrocyte. The metHb formation was reduced 1%/hr to 0.3%/hr by the addition of metHb reduction system. The blood pressure increased transiently during injection, and then immediately returned to preinjection level. Our observations suggest that the NRC are efficient oxygen carriers without causing serious adverse reactions, with controllable metHb formation in vivo and during storage.抄録全体を表示PDF形式でダウンロード (741K) -
Kaoru Nagao, Yuichi Takakuwa, Sumie Manno, Hidehiro Suzuki1995 年 20 巻 4 号 p. 287-295
発行日: 1995/07/01
公開日: 2011/03/04
ジャーナル フリーSkeletal proteins of red blood cells appear to be importantly involved in regulating the membrane mechanical properties that arise with membrane deformability and stability. However, the effects of limited digestion of skeletal proteins by proteases remain to be clearly determined. To clarify whether proteases such as trypsin inhibitor-sensitive protease (s) and μ-calpain, a Ca2+-dependent neutral protease affect membrane mechanical properties through proteolysis of membrane proteins, assessment was made of membrane stability of resealed ghosts treated with exogenous μ-calpain in the presence of the Ca2+ and/or the trypsin inhibitor. Membrane proteins were analyzed by SDS-polyacrylamide gel electrophoresis and immunobotting using antibodies against red cell membrane proteins. Untreated ghosts showed decreased membrane stability and degradation of ankyrin. Inhibition of membraneassociated protease activity by the trypsin inhibitor restored normal membrane stability and prevented ankyrin degradation. When membranes previously treated with 4 U/ml of μ-calpain in the presence of 10μM Ca2+ at 0°C were resealed in the presence of trypsin inhibitor, membrane stability decreased and only ankyrin was degradated, producing a polypeptide of 195-kD. With increase in calpain treatment time, ankyrin decreased with increase in the 195-kD polypeptide. Correlation between membrane stability and calpain effects was demonstrated by increase in this polypeptide and decrease in membrane stability. Elevation of cytosolic Ca2+ to more than 1 μM would thus appear to cause decrease in membrane stability through Ca2+-activated limited digestion of ankyrin by μ-calpain.抄録全体を表示PDF形式でダウンロード (1397K) -
曽田 房雄1995 年 20 巻 4 号 p. 296-298
発行日: 1995/07/01
公開日: 2011/03/04
ジャーナル フリーThe air blow-back asymmetric polysulfone membrane filter has been developed for power plant condensate polishing apprications. The advantages are its, high flow rate, low pressure drop and a maximum temperature resistance of 65°C.
These filters have been applied for fossil power plant and nuclear power plant in the U.S.A. and are expected to be applide in Japan.抄録全体を表示PDF形式でダウンロード (503K)
- |<
- <
- 1
- >
- >|