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Y Uda

Publications and source records attributed to Y Uda.

68 records · Page 4Linked to original sources
PubMed1976

Affinity of sphingomyelin in myelin proteolipid of bovine brain white matter.

A preparation of proteolipid, the principal component of the myelin sheath, was obtained from the bovine brain white matter with satisfactory reproducibility. Much of the lipid portion, containing most of the component sphingomyelin, was removed by precipitation with a mixture of ethanol and ether, and the precipitate fraction exhibited a preferential affinity for sphingomyelin. Since phosphatidylcholine, which did not show so much combining affinity for the precipitate fraction, exhibited an enhanced interaction by means of hydrogenation of the fatty chains, it is assumed that the affinity of sphingomyelin depends on the hydrophobic region of the molecule. Sphingomyelin is considered to interact with a complex formed by the ionic linkage between the basic protein and acidic phospholipid, which is obtained by further removal of the lipid portion from the precipitate fraction by dialysis.

Animals↗
PubMedDate not supplied

Application of a spray drying technique in the production of TRH-containing injectable sustained-release microparticles of biodegradable polymers.

Copoly (dl-lactic/glycolic acid) microparticles for sustained release of a water-soluble drug (Thyrotropin releasing hormone: TRH) were prepared by a spray drying method. A higher entrapment ratio was achieved with the spray drying method with the in-water drying method. In order to avoid agglomeration of the microparticles, a double-nozzle spray drying method was designed using mannitol as an anti-adherent. The surface of the spray-dried microparticles was coated with mannitol, and the extent of agglomeration was decreased. Acetonitrile was the most suitable solvent for microencapsulation using the double-nozzle spray drying method because the initial burst of TRH from the microparticles during the first day was the smallest. When PLGA with a weight-average molecular weight of 14,000 was used, constant release of TRH continued for one month with a small initial burst. In conclusion, the production of biodegradable microparticles by the double-nozzle spray drying method appears to be an attractive alternative to conventional microencapsulation methods.

Biodegradation, Environmental↗
PubMedDate not supplied

Natural infection with attaching and effacing Escherichia coli (O 103:H-) in chicks.

The existence of natural infection with attaching and effacing Escherichia coli (AEEC) in chicks was reported. Numerous Gram-negative bacilli were attached to the enterocyte in association with lesions characterized on a wavy appearance of the mucosal surface in the intestines of six chicks. Immunohistochemically, these bacteria reacted positively with antiserum to Escherichia coli (O 103). By electron microscopy, numerous colibacilli were seen to be closely attached to the surface membranes of the enterocytes. In regions of bacterial attachment, almost all cell microvilli were effaced, and some of the remaining ones were elongated and/or disoriented. Part of the cell membrane formed a cup invagination and pedestal-like protrusion associated with the attached bacteria. A concentration of electron-dense material was seen beneath the adherent organisms. Bacteriologically, numerous E. coli (O 103:H-) were isolated from the jejunal contents of two chicks and the E. coli did not produce verotoxin or enterotoxin. The characteristic lesions could also be induced in the cecal mucosa of young chicks experimentally inoculated with the isolated E. coli. This is the first report of natural infection in chicks with AEEC.

Animals↗