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Biomedical subjects

T Nishida

Publications and source records attributed to T Nishida.

At least 559 records · Page 31Linked to original sources
PubMed1988

Chemotactic and haptotactic activities of fibronectin for cultured rabbit corneal epithelial cells.

A previous study reported that both fibronectin and epidermal growth factor (EGF) stimulated corneal epithelial resurfacing. Fibronectin appears in the cornea after injury, and corneal epithelial cells migrate over the temporary fibronectin matrix. To determine whether fibronectin serves as chemoattractant and haptoattractant for the directed movement of corneal epithelial cells, the directed migration of cultured rabbit corneal epithelial cells was measured in vitro using a Boyden chamber. Chemotactic and haptotactic migration were assayed separately. Fibronectin was found to stimulate attachment of corneal epithelial cells and to have chemotactic, haptotactic and chemokinetic activities for the corneal epithelial cells. In contrast, EGF had no chemotactic activity.

Animals↗
PubMed1987

Immunoreactive vasoactive intestinal polypeptide in acinic cell carcinoma of the parotid gland.

Vasoactive intestinal polypeptide (VIP) in the neoplastic cells of acinic cell carcinomas arising in the human parotid gland was found immunohistochemically, whereas other parotid gland tumors, such as pleomorphic adenoma, Warthin's tumor, oxyphilic adenoma, mucoepidermoid carcinoma, adenocarcinoma, and adenoid cystic carcinoma, did not show positive immunoreactivity for VIP. The acinic cell carcinoma stained with Grimelius impregnation and had dense core granules immunoreactive with anti-VIP serum. Moreover, a comparatively high concentration of immunoreactive VIP was detected by radioimmunoassay in an acinic cell carcinoma, whereas VIP concentration of the other tumors was undetectable.

Carcinoma↗
PubMed1987

Purification and characterization of recombinant human interleukin-1 beta produced in Escherichia coli.

Recombinant human interleukin-1 beta (rIL-1 beta) produced in Escherichia coli was purified to homogeneity by a combination of mass ion exchange column chromatography, ion exchange and gel filtration high performance liquid chromatography. The purified rIL-1 beta had a molecular weight of 18 kD on SDS-polyacrylamide gel electrophoresis and an isoelectric point of 6.9 on analytical isoelectric focusing. These values were almost same as those of natural interleukin-1 beta. The amino acid composition and amino acid sequence of the amino terminal region were consistent with those deduced from the cDNA sequence. In addition, the primary structure was confirmed by peptide mapping with lysyl-endopeptidase on reverse phase HPLC. Besides rIL-1 beta with amino terminal Ala, two molecular species, [Met0] rIL-1 beta and [desAla1] rIL-1 beta, were also obtained. Biological and physicochemical properties of the three species of rIL-1 beta were compared.

Amino Acid Sequence↗
PubMed1987

High-performance liquid chromatographic analysis of serum long-chain fatty acids by direct derivatization method.

A new visible-ultraviolet labelling method for the high-performance liquid chromatographic analysis in serum of individual free fatty acids, including polyunsaturated fatty acids, is described. Without commonly used isolation steps, fatty acids in serum were directly derivatized by treatment with acidic 2-nitrophenylhydrazine hydrochloride. The derivatized fatty acids were extracted into n-hexane and separated isocratically on a reversed-phase C8 column within 15 min. The detection limits ranged from 400 fmol to 1 pmol and from 100 to 200 fmol per injection with visible and ultraviolet detection, respectively. Visible detection had better selectivity, and free fatty acid levels were determined in sera obtained from healthy controls and patients with diabetes mellitus. In all the subjects studied, the precise quantitation could be performed with 25 microliters of serum. Analytical recoveries ranged from 98.3 to 103.4%. The intra- and inter-assay coefficients of variation were less than 2.7 and 3.5%, respectively. The present method is superior to the previously published methods for routine analyses: it is cheaper, the procedure is simpler, the analysis time is shorter and both resolution and sensitivity are better.

Chromatography, High Pressure Liquid↗
PubMed1987

cDNA cloning of IL-1 alpha and IL-1 beta from mRNA of U937 cell line.

Clones of cDNAs encoding growth inhibitory factors for human melanoma cell line A375 were isolated from cDNA library prepared by using mRNA derived from human histiocytic lymphoma cell line U937 induced with PMA and further stimulated with LPS. Cloning was achieved using Okayama-Berg cDNA expression vector system that permits expression of the inserted cDNA segments in mammalian cells. By assaying the transfected COS-1 cells supernatants and cell extracts, we isolated two distinct cDNA clones encoding growth inhibitory factors. It was determined by the nucleotide sequences of the inserts, the cDNAs corresponded to IL-1 alpha and -1 beta. Our results indicate U937 cells can be induced to produce both interleukin-1s.

Amino Acid Sequence↗
PubMed1987

Peroxidative injury of the mitochondrial respiratory chain during reperfusion of hypothermic rat liver.

Mitochondrial dysfunction in ischemic liver has been demonstrated to be due to decrease in the intramitochondrial level of ATP and the subsequent disruption of the proton barrier of the inner membrane (Watanabe, F., Hashimoto, T. and Tagawa, K. (1985) J. Biochem. 97, 1229-1234). In this study, another injury process, impairment of the electron-transfer system, which occurred during reoxygenation of ischemic liver, was studied during reperfusion of cold preserved liver and during cold incubation of isolated rat-liver mitochondria. The sites of the respiratory chain that were sensitive to peroxidative damage were ubiquinone-cytochrome c oxidoreductase and NADH-ubiquinone oxidoreductase. These enzymic activities decreased with increase in lipid peroxidation. Incubation of submitochondrial particles with t-butyl hydroperoxide or with an NADPH-dependent peroxidation system decreased the enzymic activities of the electron-transport system. These data strongly suggested that lipid peroxidation during reoxygenation of ischemic liver impaired the electron-transfer system. Thus, mitochondria of ischemic liver suffer from two different types of injury: increase in proton permeability during anoxia, and decrease in enzymic activities of the electron-transport system during reoxygenation.

Animals↗
PubMed1987

Body weights of wild chimpanzees (Pan troglodytes schweinfurthii) of the Mahale Mountains National Park, Tanzania.

Ten male and nine female habituated chimpanzees (Pan troglodytes schweinfurthii) in the Kasoje area of the Mahale Mountains National Park, Tanzania, were weighed intermittently between December 1973 and March 1980 by luring them up a rope hung on a spring balance: six adult males averaged 42.0 kg and eight adult females 35.2 kg. Seasonal change in body weight was recognized at least partially; body weights tended to decrease in the later part of the wet season presumably because of food shortage in the middle of the wet season. Comparison of body weight among three populations of the same subspecies suggests that adult female chimpanzees of Mahale appear to be heavier than those of the Gombe National Park, Tanzania, and that they seem to be similar to the forest-living counterparts of eastern Zaire. On the other hand, body weights of adult male chimpanzees from the three populations do not show significant differences. Perhaps feeding competition among adult females in a small, isolated habitat is more severe than that among adult males, which may result in the body weight reduction among adult female chimpanzees at Gombe.

Animals↗
PubMed1987

Electron-microscopic studies on the presence of gap junctions between corneal fibroblasts in rabbits.

Corneal fibroblasts, major cellular components of the corneal stroma, are loosely arrayed between collagen lamellae. They play an important role in the metabolic and physiological homeostasis mechanisms by which the cornea is kept transparent. This paper deals with the demonstration of the gap junctions between the corneal fibroblasts of rabbits by transmission electron microscopy of thin sections and of freeze-fracture specimens. Under the transmission electron microscope, the corneal fibroblasts are seen between the lamellae of collagen fibers of the corneal stroma. Their long cytoplasmic processes are in contact with those of neighboring fibroblasts. Typical gap junctions are found between these cytoplasmic processes. In the freeze-fracture images, intramembrane particles with a diameter of 10.3 nm form polygonal aggregates on P faces. These findings suggest that corneal fibroblasts, coupled with each other, might function synchronously through gap junctions responsible for metabolic activities essential for the maintenance of corneal transparency.

Animals↗
PubMed1987

Uptake of india ink particles and latex beads by corneal fibroblasts.

The fate of India ink particles and polystyrene latex beads injected into the corneal stroma of rabbits was studied by the naked eye, light microscopy, and electron microscopy. All the injected ink particles or latex beads were unchanged in shape, size, and number for at least 6 months. India ink particles and latex beads were endocytosed by the corneal fibroblasts within 3-4 days after injection. Numerous ink particles were packed into vacuoles, 0.5-10 micron in diameter, which occupy a large volume of the cytoplasm of the cell body and processes of fibroblasts in and near the injected area. Each latex bead, 0.72 micron in diameter, is usually enclosed in one vesicle, and a large number of vesicles are distributed throughout the cytoplasm. In corneal tissue removed 10 min after injection of India ink and cultured for 3 or 7 days, uptake of many ink particles by the fibroblasts was seen. By this experiment, the contribution of the blood-derived cells was completely excluded, and it is more distinctly shown that the corneal fibroblast has a strong endocytotic activity. The uptake and long-term storage of ink particles and latex beads by the corneal fibroblast are reactions that protect the organ without inflammation from the injury and harm by non-toxic foreign materials.

Animals↗
PubMed1987

Spontaneous persistent epithelial defects after cataract surgery.

The natural course of corneal epithelial erosions was studied retrospectively in patients who had undergone cataract extraction. Postsurgical epithelial defects occurred in 41 of 796 eyes (5.2%). No difference was noted in the incidence of corneal epithelial defects in eyes after intracapsular and extracapsular cataract extraction. Of the 41 eyes with postsurgical corneal erosion, 26 (63.4%) showed corneal epithelial defects by the fourth postoperative day. Two types of healing patterns were noticed: rapid healing, in which there was complete epithelial resurfacing within 4 days after the onset of corneal erosion, and prolonged healing, in which the period for complete epithelial resurfacing ranged from 6 days to 34 days. Since fibronectin has been reported to facilitate corneal epithelial migration and adhesion, we administered autologous fibronectin eyedrops in five cases in which corneal epithelial erosion developed after cataract surgery and epithelial defects persisted more than 7 days (except case 2). In all cases receiving fibronectin treatment, complete epithelial resurfacing occurred. In four of five eyes, fibronectin eye drops were effective in epithelial resurfacing within 3-9 days; in one eye, complete epithelial resurfacing took 23 days. The present results indicate that there are two types of epithelial erosion and that fibronectin eye drops might be one of the possible therapeutic approaches for the treatment of persistent epithelial defects. The weak adhesion of epithelial cells underlying basement membrane may be one of the causes of persistent epithelial defects after cataract surgery.

Adult↗
PubMed1987

Levels of purine compounds in a perfusate as a biochemical marker of ischemic injury of cold-preserved liver.

Biochemical markers of ischemic injury of rat liver were studied in an extracorporeal perfusion system. During anoxic perfusion, purine compounds appeared in the perfusate as soon as they were formed in the liver and their recovery in the perfusate balanced the loss of adenine nucleotides from the liver. In contrast, cytosolic aspartate aminotransferase did not appear in the perfusate at slow rates of liver perfusion or during hypothermic perfusion. The production of purine compounds was further investigated in hypothermically preserved liver in connection with the restoration of some metabolic functions of liver. The amount of purine compounds released into the perfusate was found to be closely related to the degrees of damage of the hepatic functions of gluconeogenesis, ureogenesis, and mitochondrial respiration on reperfusion. These results indicate that release of purine compounds into the perfusate is a good marker of ischemic damage.

Adenine Nucleotides↗
PubMed1987

Effects of medroxyprogesterone acetate on sleep of healthy young male adults.

The effects of a single 100 mg dose of medroxyprogesterone acetate (MPA) on human sleep were investigated using healthy young male adults. After a baseline night recording, two consecutive MPA nights and the following two withdrawal nights were recorded. The total sleep time was reduced after the 2nd MPA night and the decrease was significant on the 1st withdrawal night. The time of intrasleep awakening increased after the 2nd MPA night. Stage 1 sleep increased significantly on the 2nd MPA and 1st withdrawal nights. Stage 4 sleep decreased and the sleep latency gradually increased after the MPA administration. REM sleep reduced slightly on the 1st withdrawal night. These results indicate that MPA has a mild arousal action on human sleep and that the action may be pronounced a few days after administration of MPA.

Adult↗
PubMed1987

Increased arachidonic acid composition of phospholipids in colonic mucosa from patients with active ulcerative colitis.

The long chain fatty acid composition of phospholipids in colonic mucosa was determined by high performance liquid chromatography in nine patients with active ulcerative colitis and eight healthy controls. The arachidonic acid composition was 12.5 +/- 1.4 mol % (mean +/- 2 SEM) in the inflamed colonic mucosa from the patients with active ulcerative colitis and 6.8 +/- 1.2 mol % in the intact mucosa from healthy controls (p less than 0.001). In the inflamed colonic mucosa, oleic acid and palmitoleic acid were concomitantly decreased (p less than 0.001 and p less than 0.02, respectively), while docosahexaenoic acid was increased (p less than 0.05). Histopathological examination showed that there was a three fold increase in the cell density of inflammatory infiltrate in the lamina propria of the inflamed colonic mucosa (p less than 0.001). The cell density of inflammatory infiltrate correlated with the arachidonic acid composition of phospholipids in colonic mucosa (r = 0.89, p less than 0.005). These findings indicate that inflammation alters the long chain fatty acid composition of phospholipids in colonic mucosa. The observed increase in the arachidonic acid composition of phospholipids in inflamed colonic mucosa may contribute to the enhanced arachidonic acid metabolism in patients with active ulcerative colitis.

Adolescent↗
PubMed1987

Fine structure of the parotid gland in the pika and the volcano rabbit.

The parotid glands of the pika and the volcano rabbit were examined by light and transmission electron microscopy. The acinar cells of the pika consisted of light cells containing basophilic granules of low density, while in the volcano rabbit the acinar cells consisted of light and dark cells containing acidophilic granules of moderate density. Intercalated duct cells were composed of light cells containing a few granules of moderate density. These segments of the two animals were similar in morphology. The striated duct cells in both species were composed of light and dark cells. Most of those in the pika contained a few moderately dense granules. In both animals, no myoepithelial cells were detected around the acini, intercalated ducts or striated ducts, while nerve terminals were observed among the adjacent acinar cells.

Animals↗