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841.
H Okamoto N Takuwa K Gonda H Okazaki K Chang Y Yatomi H Shigematsu Y Takuwa 《Canadian Metallurgical Quarterly》1998,273(42):27104-27110
In Chinese hamster ovary (CHO) cells transiently transfected with an expression vector for EDG1, but not an empty vector, sphingosine-1-phosphate (SP) at a concentration as low as 10(-10) M caused an increase in the intracellular free Ca2+ concentration ([Ca2+]i) as a result of mobilization of Ca2+ from both intracellular and extracellular pools. In a CHO clone stably expressing EDG1 receptor (CHO-EDG1 cells), SP induced increases in the production of inositol phosphates and the [Ca2+]i and inhibited forskolin-induced increase in the cellular cAMP content, all in a manner sensitive to pertussis toxin. SP also activated mitogen-activated protein kinase in CHO-EDG1 cells in pertussis toxin-sensitive and Ras-dependent manners. To evaluate the spectrum of agonists for EDG1, we used human erythroleukemia (HEL) cells, which at naive state do not respond to SP or structurally related lipids with an increase in the [Ca2+]i. In HEL cells stably expressing EDG1 receptor (HEL-EDG1 cells), SP dose-dependently increased the [Ca2+]i with half-maximal and maximal concentration values of 10(-9) and 3 x 10(-7) M, respectively; sphingosylphosphorylcholine at exclusively high concentrations, but not sphingosine at all, also increased the [Ca2+]i. HEL-EDG1 cells bound 32P-labeled SP, which was displaced dose dependently by unlabeled SP. These results indicate that EDG1, a member of the EDG family G protein-coupled receptors, is a specific, high-affinity SP receptor. 相似文献
842.
5-Hydroxytryptophan (5-HTP) is the intermediate metabolite of the essential amino acid L-tryptophan (LT) in the biosynthesis of serotonin. Intestinal absorption of 5-HTP does not require the presence of a transport molecule, and is not affected by the presence of other amino acids; therefore it may be taken with meals without reducing its effectiveness. Unlike LT, 5-HTP cannot be shunted into niacin or protein production. Therapeutic use of 5-HTP bypasses the conversion of LT into 5-HTP by the enzyme tryptophan hydroxylase, which is the rate-limiting step in the synthesis of serotonin. 5-HTP is well absorbed from an oral dose, with about 70 percent ending up in the bloodstream. It easily crosses the blood-brain barrier and effectively increases central nervous system (CNS) synthesis of serotonin. In the CNS, serotonin levels have been implicated in the regulation of sleep, depression, anxiety, aggression, appetite, temperature, sexual behaviour, and pain sensation. Therapeutic administration of 5-HTP has been shown to be effective in treating a wide variety of conditions, including depression, fibromyalgia, binge eating associated with obesity, chronic headaches, and insomnia. 相似文献
843.
Tsugio Horii Hitoshi Okazaki Minoru Kino Yohnosuke Kobayashi Kiyoshi Satouchi Kunihiko Saito 《Lipids》1991,26(12):1292-1296
It recently has been recognized that platelet-activating factor (PAF) may be a mediator of asthma exacerbation. We had the
opportunity to analyze bronchoalveolar lavage fluids from an asthmatic infant, which were characterized by neutrophil infiltration.
The patient's lungs were washed on three occasions with saline during asthmatic attacks. PAF was found in each case on the
basis of its ability to cause the immediate aggregation of washed rabbit platelets. The PAF detected was equivalent to 1–1.4
pmol of 1-O-hexadecyl-2-acetyl-sn-glycero-3-phosphocholine, three quarters of which were recovered in cell-associated form. By contrast, we did not detect
PAF in bronchoalveolar exudates from patients with larungeal stenosis or with respiratory distress syndrome. LysoPAF, the
direct precursor as well as initial metabolite of PAF, was also analyzed after being converted to PAF by acetylation. There
was a wide variation in the amount of lysoPAF present in individual patients, suggesting that lysoPAF levels cannot be taken
as an indicator for the presence of PAF.
Based on a paper presented at the Third International Conference on Platelet-Activating Factor and Structurally Related Alkyl
Ether Lipids, Tokyo, Japan, May 1989. 相似文献
844.
Takeshi Furuta Susumu Tsujimoto Hideaki Makino Morio Okazaki Ryozo Toei 《Journal of food engineering》1984,3(3):169-186
Capillary cell and absorption-desorption methods were used to measure the diffusion coefficients of water and ethanol in aqueous maltodextrin solution over a wide range of water content. The diffusion coefficients showed a surprisingly large dependence on water content, particularly at low water content, as reported by other workers. Free volume theory was applied to correlate the diffusion coefficients. It was found that this theory was adequate to explain their large dependence on water content. Furthermore, experimental results on ethanol retention in drying an aqueous maltodextrin droplet could be predicted well, using the present experimental results for the diffusion coefficients of water and ethanol. 相似文献
845.
846.
847.
M Ajima K Usuki A Igarashi R Okazaki K Hamano A Urabe Y Totsuka 《Canadian Metallurgical Quarterly》1997,36(9):640-642
BACKGROUND: The appropriate management of patients who are older than 80 years of age and who present with an abdominal aortic aneurysm (AAA) remains controversial. While it appears that elective repair can be performed safely, appropriate management of these patients in the emergency situation is unclear. The purpose of the present study was to examine the results obtained in treating this elderly group in the elective and emergency setting, by operation and conservative techniques at St George Hospital, Kogarah. METHODS: Between January 1987 and December 1994 85 patients older than 80 years of age were treated for AAA. These patients were divided into four groups: I, elective presentation/no surgery; II, elective presentation/elective surgical repair; III, emergency presentation/surgical repair; and IV, emergency presentation/conservative treatment. We examined age, sex, size of AAA, mode of presentation, type of treatment, length of survival and cause of death. RESULTS: The mean age of the total group (n = 85) of patients was 84 years (range: 80-94). The mean AAA diameter for this group was 5.6 cm (95% CI: 5.2-6 cm). The diameters for group I (n = 40), II (n = 22), III (n = 16) and IV (n = 7) were 4.9 cm (4.4-5.5, 95% CI), 5.7 (4.9-6.5 CI), 7.0 (6.1-7.7 CI) and 6.2 (5.2-7.2 CI), respectively. The median survival for groups I, II, III and IV was 18, 38.5, 0.25 and 0 months, respectively. Group II had a longer survival than any other group (P = 0.015), and group IV had a shorter survival than the total group (P = 0.001). However, the length of survival was no different for III versus IV (P = 0.146). Deaths in each group were due to the following reasons. I: cardiopulmonary events (14), rupture (3), malignancy/sepsis (3); II: cardiopulmonary events (3), rupture (thoracic aneurysm) (2), malignancy (I); III: rupture (10), malignancy (I); and (IV): rupture (6), malignancy (1). CONCLUSIONS: Elective surgical repair offers the best management option for AAA in patients older than 80 years of age. Death may still occur from progression of aneurysmal disease at other sites. An aggressive surgical approach to the management of haemodynamically unstable patients in this age group is of questionable benefit. 相似文献
848.
Phosphatidate phosphohydrolase (PAPase) activity was measured in lamellar bodies purified from porcine lung tissue. After
repeated freeze-thawing, only a negligible amount of PAPase activity was released into the soluble fractions, whereas there
was release of 2 lysosomal marker enzyme activities, glucosaminidase and β-galactosidase into the soluble fraction. In addition,
a lysosomal-enriched fraction was prepared from adult rat lung tissue by prior treatment of the rats with Triton WR 1339.
Treatment with Triton WR 1339 resulted in the significant shift of the activities of the lysosomal marker enzymes, glucosaminidase
and β-galactosidase, to less dense subcellular fractions. The highest specific activity of PAPase was found in a subcellular
fraction which had a density that was intermediate between that of the mitochondrial and microsomal fractions and the distribution
of PAPase activity was not affected by the prior treatment of the rats with Triton WR 1339. 相似文献
849.
T Watanabe O Okazaki Y Akutsu H Yamanaka T Michihata T Katagiri K Harumi 《Canadian Metallurgical Quarterly》1998,39(3):275-285
In Poland cutaneous form of anthrax is occurring sporadically. Most of these cases were recognized in the eastern part of the country adjacent to the eastern border (Lomza region and others). The latest literature on epidemiology, diagnosis, prevention and treatment of anthrax is reviewed in order to spread modern views on anthrax and to implement changes in the diagnostic methods of anthrax in Poland. 相似文献
850.
Y Matsuoka Y Kitamura M Okazaki J Kakimura I Tooyama H Kimura T Taniguchi 《Canadian Metallurgical Quarterly》1998,85(4):1223-1233
Heme oxygenase, catalyses oxidation of the heme molecule in concert with NADPH-cytochrome P450 reductase and then specifically cleaves heme into biliverdin, carbon monoxide, and iron. Biliverdin and its product, bilirubin, are known to be strong antioxidants. Kainic acid is a potent neurotoxin, and induces selective neuronal loss in the rat hippocampus. Kainic acid acts on the kainate receptors, and kainic acid neurotoxicity may be in part mediated by oxidative stress. In this study, we examined whether or not heme oxygenase was activated in kainic acid-induced neurotoxicity. After intracerebroventricular injection of kainic acid, the heme oxygenase-1 protein level was strongly enhanced, although the constitutive heme oxygenase (heme oxygenase-2) protein level was not changed. One day after treatment, the protein level of heme oxygenase-1 reached a maximum and then gradually decreased over a period of three to seven days. In the rat hippocampus, cells expressing heme oxygenase-1 in vivo were predominately microglia and only a few astrocytes. In addition, heme oxygenase-1 immunoreactivity was predominantly co-localized with major histocompatibility complex class II-, and partly co-localized with class I-immunoreactive microglia. In cultured glial cells in vitro, heme oxygenase- protein was expressed in the microglia even with the vehicle treatment, and was strongly induced in astrocytes by kainic acid treatment. These results suggest that ameboid microglia, which express both heme oxygenase-1 and major histocompatibility complex antigens, may play a key role in a delayed episode of kainic acid-induced microglial activation and neurodegeneration. 相似文献