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21.
Hans-Georg Elias Daniel C. Chung Nobuo Donkai Goetz P. Hellmann Karel Solc Katsutoshi Nagai 《Macromolecular chemistry and physics.》1987,188(3):537-560
1-O-3-(4-Vinylphenyl)propyl-β-D -glucopyranose ( 1 ) undergoes in water a closed association under formation of N-mers. The unimer/N-mer association is directly visible in the Schlieren pattern of ultracentrifugal synthetic boundary experiments. Association numbers and mass-concentration-based equilibrium constants of association were calculated from the variation of N-mer concentrations with unimer concentrations and from the concentration dependence of inverse apparent average molar masses as measured by both vapor phase osmometry and sedimentation equilibrium. Association numbers were also calculated from the combination of sedimentation coefficients with diffusion coefficients, sedimentation coefficients with intrinsic viscosities, and diffusion coefficients with interinsic viscosities as well as from the dependence of apparent mass-average molar masses on inverse apparent number-average molar masses. All methods gave in general different association numbers and equilibrium constants. The effect, which was not found for other non-ionic amphiphiles, is probably due to the existence of consecutive equilibria between the unimer and a low molar mass P-mer which associates to a higher molar mass R-mer. Viscosity data are in agreement with the picture of a spherical micelle for the dominant P-mers with about 10 water molecules per glucose residue. The micellization of 1 is both enthalpy- and entropy-driven, in contrast to the micellization of 1-O-octyl-β-D -glucopyranose which is a strictly entropy-driven process. 相似文献
22.
Keisuke Morita MD ; Kazunori Urabe ; Yoichi Moroi ; Tetsuya Koga ; Ryuji Nagai ; Seiko Horiuchi ; Masutaka Furue 《Wound repair and regeneration》2005,13(1):93-101
Advanced glycation end products are the chemical modification of proteins induced by sugars in a hyperglycemic condition. Extracellular matrix proteins are prominent targets of nonenzymatic glycation because of their slow turnover rates. The aim of this study was to investigate the influence of nonenzymatic glycation of type I collagen on the migration of keratinocytes. The migration of keratinocytes was dramatically promoted on native type I collagen-coated dishes compared with that on uncoated dishes. When type I collagen was glycated with glycolaldehyde, large amounts of advanced glycation end products were produced; the glycated collagen I-coated dishes did not promote the migration of keratinocytes. Glycated collagen I did not affect the proliferative capacity of keratinocytes. However, the adhesion of keratinocytes to glycated collagen I was profoundly diminished in a glycation intensity-dependent manner. alpha2beta1 integrin is responsible for the migration and adhesion of keratinocytes to type I collagen. Pretreatment with glycated collagen I did not affect the expression level or functional activity of alpha2beta1 integrin on keratinocytes. These findings suggest that in the presence of glycated collagen I, keratinocytes lose their adhesive and migratory abilities. As the glycation did not modify the alpha2beta1 integrin on keratinocytes, it is suggested that glycation may diminish the binding capacity of type I collagen. 相似文献
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Joji Ishikawa Satoshi Hoshide Seiichi Shibasaki Yoshio Matsui Tomoyuki Kabutoya Kazuo Eguchi Shizukiyo Ishikawa Thomas G Pickering Kazuyuki Shimada Kazuomi Kario 《Hypertension research》2006,29(3):153-159
Morning blood pressure is reported to be more closely related to hypertensive organ damages such as left ventricular mass index, microalbuminuria and silent cerebral infarcts, than blood pressure at other times of the day. Morning blood pressure may play an important role in the pathogenesis of hypertensive target organ damage. Increased sympathetic nerve activity is reported to be one of the mechanisms of morning hypertension; however, there are no available data that show whether strict home blood pressure control, especially in the morning period, can reduce target organ damage. The Japan Morning Surge-1 (JMS-1) study includes hypertensive outpatients with elevated morning systolic blood pressure (>or=135 mmHg) as assessed by self-measured blood pressure monitoring at home. All enrolled patients are under stable antihypertensive medication status. Exclusion criteria are arrhythmia, chronic inflammatory disease, and taking alpha-blockers or beta-blockers. The target number of patients to be enrolled in the JMS-1 study is 600, and the aim is to evaluate differences in the markers of hypertensive target organ damage, such as brain natriuretic peptide and the urinary albumin excretion/creatinine ratio. All of the patients are randomized to an experimental group or a control group, with randomization to be carried out by telephone interviews with the patients' physicians. In the experimental group, patients begin taking additional antihypertensive medication just before going to bed. This consists of doxazosin 1 mg/day, which then is increased to 2 mg/day and 4 mg/day, with a beta-blocker added after a 1-month interval until the morning systolic blood pressure is controlled to less than 135 mmHg. Patients in the control group continue the treatment they are receiving at the enrollment for 6 months. Blood pressure levels, adverse effects, and hypertensive target organ damage before and after the study are evaluated. In the JMS-1 study, we will evaluate whether strict morning blood pressure control by sympathetic nervous system blockade using an alpha-blocker, doxazosin, and with the addition of a beta-blocker if needed, can reduce hypertensive target organ damage. 相似文献
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26.
Yu-Yan Fan Ryoko Baba Yukiko Nagai Akira Miyatake Naohisa Hosomi Shoji Kimura Guang-Ping Sun Masakazu Kohno Mamoru Fujita Youichi Abe Akira Nishiyama 《Hypertension research》2006,29(3):169-178
Recent studies have suggested that aldosterone plays a role in the pathogenesis of renal injury. In this study, we investigated whether local angiotensin II (Ang II) activity contributes to the progression of renal injury in aldosterone/salt-induced hypertensive rats. Uninephrectomized rats were treated with 1% NaCl in a drinking solution and one of the following combinations for 6 weeks: vehicle (2% ethanol, s.c.; n=9), aldosterone (0.75 mug/h, s.c.; n=8), aldosterone+Ang II type 1 receptor blocker olmesartan (10 mg/kg/day, p.o.; n=8), or aldosterone+olmesartan (100 mg/kg/day, p.o.; n=9). Aldosterone/salt-treated hypertensive rats exhibited severe proteinuria and renal injury characterized by glomerular sclerosis and tubulointerstitial fibrosis. Aldosterone/salt-induced renal injury was associated with augmented expression of angiotensin converting enzyme and Ang II levels in the renal cortex and medullary tissues. Renal cortical and medullary mRNA expression of transforming growth factor-beta (TGF-beta) and connective tissue growth factor (CTGF) as well as the collagen contents were increased in aldosterone/salt-treated hypertensive rats. Treatment with olmesartan (10 or 100 mg/kg/day) had no effect on blood pressure but attenuated proteinuria in a dose-dependent manner. Olmesartan at 10 mg/kg/day tended to decrease renal cortical and medullary Ang II levels, TGF-beta and CTGF expression, and collagen contents; however, these changes were not significant. On the other hand, an ultrahigh dose of olmesartan (100 mg/kg/day) significantly decreased these values and ameliorated renal injury. These data suggest that augmented local Ang II activity contributes, at least partially, to the progression of aldosterone/salt-dependent renal injury. 相似文献
27.
Kazuo Yamakawa Masashi Takanashi Masao Watanabe Noriyuki Nakamura Tomonori Kobayashi Masato Hasegawa Yoshikuni Mizuno Shigeki Tanaka Hideo Mori 《Neuropathology》2006,26(6):586-591
We report on a male patient with Pick disease who had shown severe white matter atrophy and dilatation of the lateral ventricle in the frontal lobe from an early stage. Upon admission to our hospital 2 years after disease onset, the patient showed apathy, and MRI revealed severe atrophy of the cortex and white matter of the frontal lobe. He died at age 74, 11 years after disease onset. Autopsy revealed severe atrophy of the frontal and temporal lobes, severe loss of white matter in the frontal lobe, dilatation of the lateral ventricles, and cortical thinning. Histopathological examination showed severe loss of myelinated fibers in the frontal white matter and severe neuronal loss with gliosis in the frontal and temporal cortices. Many Pick bodies were seen. Our patient had a rare case of Pick disease predominantly affecting the frontal lobe with severe involvement of the white matter from an early stage. This case suggests that myelinated fibers in the white matter as well as cerebral neurons are primarily affected in Pick disease. 相似文献
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Kazuhiko Kyoshima Susumu Oikawa Miki Kanaji Hideo Zenisaka Takeomi Takizawa Tetsuya Goto Hisayoshi Takasawa Atsushi Watanabe Kazuo Tokushige Keiichi Sakai 《Journal of clinical neuroscience》2003,10(5):571-578
Some chordomas have a very poor prognosis because of their aggressive growth nature, but the efficacy of repeat operations for these cases has not been well documented. This report concerns 3 patients with aggressive chordoma of the clivus, who underwent operations 6 to 12 times over a period of 8 to 17 years because of symptomatic regrowth. Overall mean interval between repeat operations was 18 months with a range from 5 to 57 months and survival times were 9 to19 years after the first surgery. Main symptoms before each operation were diplopia and visual disturbance. Repeat palliative operations by intentional extradural debulking of the tumour to decompress offending neural structures, as well as maximal removal of the tumour, using appropriate skull base approaches, can mitigate progressive symptoms, and may result in better quality and some prolongation of life, although our patients gradually deteriorated neurologically throughout the clinical course. 相似文献
30.
In the liver ischemia-reperfusion model, the lipid peroxide level increased during ischemic periods, while a greater increase was observed during reflow periods. The increase in the cytochrome b5 content was observed during ischemia and reflow periods. On the contrary, the cytochrome P-450 content remained unchanged during ischemic periods, but decreased during reflow periods. Bifemelane suppressed the elevation of the lipid peroxide level, the cytochrome b5 content and the decrease in cytochrome P-450 content during the period of reperfusion. 相似文献