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61.
The study investigated how the pressure exerted on the skin by clothing worn while working in the daytime affected the urinary excretion of adrenaline, noradrenaline and cortisol, heart rate, and also melatonin secretion at night. Nine young women (experiment I) and seven young women (experiment II) participated. Participants wore either a 100% cotton jacket (tight clothes, TC) or a 100% cotton T-shirt (loose clothes, LC). Loose-fitting, 100% cotton tank tops and panties were worn as underwear in both the TC and the LC groups. The main results can be summarized as follows: (1) urinary excretion of adrenaline, noradrenaline and cortisol was facilitated, and the amounts of urinary excretion were significantly higher when TC were worn. Heart rate was significantly higher in the TC group; (2) nocturnal urinary melatonin excretion was significantly greater in the TC group. These results are discussed in terms of an enhancement of diurnal sympathetic nervous system activity caused by pressure on the skin produced by tight clothing. 相似文献
62.
Hashimoto T Nonaka Y Minato K Kawakami S Mizuno M Fukuda I Kanazawa K Ashida H 《Bioscience, biotechnology, and biochemistry》2002,66(7):1610-1614
To investigate the effects of lentinan from Lentinas edodes and polysaccharides from Agaricus blazei (ABPS) on the expression of cytochrome P450s (CYPs), lentinan (10 mg/kg/day) or ABPS (200 mg/kg/day) was administered to female BALB/c mice four times every other day by intraperitoneal injection. Lentinan and ABPS suppressed both the constitutive and 3-methylcholanthrene-induced CYP1A expression and ethoxyresorufin-O-deethylation activity in the liver. 相似文献
63.
Katayama Y Fujii K Ito E Sakakihara S Sonoda T Murata M Maeda M 《Biomacromolecules》2002,3(5):905-909
We describe two types of artificial gene-regulation systems responding to cyclic AMP-dependent protein kinase (PKA) or caspase-3. These molecular systems use newly synthesized cationic polymers, PAK and PAC. The PAK polymer includes substrate oligopeptide for PKA, ARRASLG, as receptor of PKA signal, while the PAC polymer possesses oligopeptide that is comprised of a substrate sequence of caspase-3, DEVD, and a cationic oligolysine, KKKKKK. These polymers formed stable complexes with DNA to totally suppress the gene expression. However, PKA or caspase-3 signal disintegrates the PAK-DNA or the PAC-DNA complex, respectively. This liberates the DNA and activated the gene expression. These systems are the first concept of an intracellular signal-responsive gene-regulation system using artificial polymer. We expect that these systems can be applied to the novel highly cell specific gene delivery strategy that is involved in our previously proposed new drug delivery concept, the drug delivery system based on responses to cellular signals. 相似文献
64.
Albutensin A (Ala-Phe-Lys-Ala-Trp-Ala-Val-Ala-Arg) derived from serum albumin dose-dependently decreased food intake after intracerebroventricular (10-50 nmol/mouse) or peripheral (0.3-1.0 micromol/mouse) administration in fasted conscious ddY mice. Albutensin A delayed gastric emptying and elevated blood glucose levels. Although albutensin A showed low affinity for bombesin receptor, it decreased food intake in bombesin receptor knockout mice, indicating that its inhibitory effect on feeding was not mediated through bombesin receptor. Then, we investigated whether the albutensin A-induced decrease in food intake was mediated by complement C3a and C5a receptors, because albutensin A had affinities for these receptors. Des-Arg-albutensin A, lacking affinity for C3a and C5a receptors, did not inhibit food intake. We found for the first time that centrally administered C3a (10-100 pmol/mouse) by itself decreased food intake in fasted mice. In contrast, C5a increased food intake after central injection. Based on these results, we conclude that the inhibitory effect of albutensin A on food intake is mediated through the C3a receptor. 相似文献
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Nakahara Y Nonaka T Hojo H Nakahara Y 《Bioscience, biotechnology, and biochemistry》2003,67(8):1761-1766
An unnatural alpha-D-mannopyranose-linked chitobiosyl dolichyl pyrophosphate, a stereoisomer of the N-glycan biosynthesis intermediate, was synthesized. The protected trisaccharide, alpha-D-Man-(1-->4)-beta-D-GlcNAc-(1-->4)-D-GlcNAc, carrying a 4-methylbenzoyl group was prepared for the convenience of a TLC analysis. 1-O-Phosphorylation, condensation with dolichyl phosphate, and subsequent deprotection afforded the title compound. 相似文献
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Tsujikawa A Kiryu J Nonaka A Yamashiro K Nishiwaki H Honda Y Ogura Y 《American journal of physiology. Regulatory, integrative and comparative physiology》2000,279(3):R980-R989
Diabetes is associated with increased neural damage after transient cerebral ischemia. Recently, leukocytes, which are thought to play a central role in ischemia-reperfusion injury, have been suggested to be involved in exacerbated damage after transient ischemia in diabetic animals. The present study was designed to clarify whether the anticipated worse outcome after transient cerebral ischemia in diabetic animals was due to augmented leukocyte-mediated neural injury. Using rats with streptozotocin-induced diabetes of 4-wk duration, we investigated leukocyte-endothelial cell interactions during reperfusion after a transient 60-min period of retinal ischemia. Unexpectedly, postischemic diabetic retina showed no active leukocyte-endothelial cell interactions during reperfusion. The maximal numbers of rolling and accumulating leukocytes in diabetic retina were reduced by 73.6 and 41.2%, respectively, compared with those in nondiabetic rats. In addition, neither preischemic insulin treatment of diabetic rats nor preischemic glucose infusion of nondiabetic rats significantly influenced leukocyte-endothelial cell interactions during reperfusion. The present study demonstrated that high blood glucose concentration before induction of ischemia did not exacerbate leukocyte involvement in the postischemic retinal injury. Furthermore, diabetic retina showed suppressed leukocyte-endothelial cells interactions after transient ischemia, perhaps due to an adaptive mechanism that developed during the period of induced diabetes. 相似文献
70.
Minehira K Inoue S Nonaka M Osada K Yamada K Sugano M 《Biochimica et biophysica acta》2000,1483(1):141-153
Exogenous oxidized cholesterol disturbs both lipid metabolism and immune functions. Therefore, it may perturb these modulations with ageing. Effects of the dietary protein type on oxidized cholesterol-induced modulations of age-related changes in lipid metabolism and immune function was examined using differently aged (4 weeks versus 8 months) male Sprague-Dawley rats when casein, soybean protein or milk whey protein isolate (WPI) was the dietary protein source, respectively. The rats were given one of the three proteins in diet containing 0.2% oxidized cholesterols mixture. Soybean protein, as compared with the other two proteins, significantly lowered both the serum thiobarbituric acid reactive substances value and cholesterol, whereas it elevated the ratio of high density lipoprotein-cholesterol/cholesterol in young rats, but not in adult. Moreover, soybean protein, but not casein and WPI, suppressed the elevation of Delta6 desaturation indices of phospholipids in both liver and spleen, particularly in young. On the other hand, WPI, compared to the other two proteins, inhibited the leukotriene B4 production of spleen, irrespective of age. Soybean protein reduced the ratio of CD4(+)/CD8(+) T-cells in splenic lymphocytes. Therefore, the levels of immunoglobulin (Ig)A, IgE and IgG in serum were lowered in rats given soybean protein in both age groups except for IgA in adult, although these observations were not shown in rats given other proteins. Thus, various perturbations of lipid metabolism and immune function caused by oxidized cholesterol were modified depending on the type of dietary protein. The moderation by soybean protein on the change of lipid metabolism seems to be susceptible in young rats whose homeostatic ability is immature. These observations may be exerted through both the promotion of oxidized cholesterol excretion to feces and the change of hormonal release, while WPI may suppress the disturbance of immune function by oxidized cholesterol in both ages. This alleviation may be associated with a large amount of lactoglobulin in WPI. These results thus showed a possibility that oxidized cholesterol-induced perturbations of age-related changes of lipid metabolism and immune function can be moderated by both the selection and combination of dietary protein. 相似文献