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171.
Kawakami F Ito M Matsuda Y Hayashi I Ohtsuki K 《Biological & pharmaceutical bulletin》2004,27(3):282-287
The phosphorylation of human C3a (hC3a, anaphylatoxin) by two distinct protein kinases (PKA and CK-I) and the effect of cholesterol-3-sulfate (CH-3S) on this phosphorylation were biochemically investigated in vitro. It was found that (i) hC3a functions as a phosphate acceptor for PKA and CK-I, but not for CK-II; (ii) the CK-I-mediated phosphorylation of hC3a requires the presence of 3 microM CH-3S in a manner similar to the phosphorylation of HMG1 (CH-3S-binding protein) by CK-I; and (iii) CH-3S inhibits the PKA-mediated phosphorylation of hC3a in a dose-dependent manner (ID50=approximately 2 microM). As expected, hC3a containing high levels of Arg- and Lys-residues stimulated approx. 3-fold CK-II activity (phosphorylation of alpha-casein) in vitro. However, no significant effect of hC3a on CK-II activity was observed when hC3a was preincubated with CH-3S or fully phosphorylated by PKA in vitro. Furthermore, preincubation of hC3a with CH-3S diminished the ability of hC3a to induce vascular permeability in rats. The results provided here suggest that (i) hC3a is a CH-3S-binding protein; and (ii) CH-3S functions as a potent inhibitor for its physiological activities, including phosphorylation by PKA and CK-I, in vitro. 相似文献
172.
Ohtsuki S 《Biological & pharmaceutical bulletin》2004,27(10):1489-1496
The blood-brain barrier (BBB) segregates the circulating blood from interstitial fluid in the brain, and restricts drug permeability into the brain. Our latest studies have revealed that the BBB transporters play important physiological roles in maintaining the brain milieu. The BBB supplies creatine to the brain for an energy-storing system, and creatine transporter localized at the brain capillary endothelial cells (BCECs) is involved in BBB creatine transport. The BBB is involved in the brain-to-blood efflux transport of the suppressive neurotransmitter, gamma-aminobutyric acid, and GAT2/BGT-1 mediates this transport process. BCECs also express serotonin and norepinephrine transporters. Organic anion transporter 3 (OAT3) and ASCT2 are localized at the abluminal membrane of the BCECs. OAT3 is involved in the brain-to-blood efflux of a dopamine metabolite, a uremic toxin and thiopurine nucleobase analogs. ASCT2 plays a role in L-isomer-selective aspartic acid efflux transport at the BBB. Dehydroepiandrosterone sulfate and small neutral amino acids undergo brain-to-blood efflux transport mediated by organic anion transporting polypeptide 2 and ATA2, respectively. The BBB transporters are regulated by various factors, ATA2 by osmolarity, taurine transporter by TNF-alpha, and L-cystine/L-glutamic acid exchange transporter by oxidative stress. Clarifying the physiological roles of BBB transport systems should give us important information allowing the development of better CNS drugs and improving our understanding of the relationship between CNS disorders and BBB function. 相似文献
173.
Kurihara H Fukami H Asami S Toyoda Y Nakai M Shibata H Yao XS 《Biological & pharmaceutical bulletin》2004,27(7):1093-1098
In the present study, we investigated the antioxidative effect of oolong tea in vitro and in vivo using the oxygen radical absorbance capacity (ORAC) assay. An oolong tea extract, catechin and related compounds suppressed the oxidation of fluorescence induced by AAPH in a dose-dependent manner, that is, they prolonged the antioxidant time in vitro. Oral administration of the oolong tea extract to mice treated with restraint stress increased ORAC activity in plasma as compared with a stress control group. The extract also increased plasma vitamin C levels, and there was a good relationship between ORAC activity and the vitamin C level in plasma. The elevation of plasma ORAC and vitamin C level may have been related to the stress-relieving effect of oolong tea. These effects are probably due to the antioxidative properties of the tea. Thus, these findings suggested that oolong tea has beneficial effects on health related to its antioxidative action. 相似文献
174.
Ohtsuki H Shiraga F Morizane Y Furuse T Takasu I Hasebe S 《American journal of ophthalmology》2004,137(1):125-134
PURPOSE: To evaluate the transposition of the anterior superior oblique insertion as a treatment for cyclovertical diplopia accompanied by an awareness of tilted image perceived with the affected eye induced from limited macular translocation (LMT). DESIGN: Observational case series. METHODS: Transposition of the anterior part of the superior oblique tendon combined with or without vertical muscle surgery on the affected eye was retrospectively studied in seven patients. Clinical outcome was assessed for binocular and monocular vision. A successful result was defined as restoration of single binocular vision (SBV) at distance and near examined with the Bagolini test with disappearance of a tilted image perceived in the affected eye. RESULTS: Six of seven patients (86%) became unaware of tilted image, and three patients (43%) obtained successful results after the strabismus surgery. Of these three patients with successful results, one (33%) patient recognized metamorphopsia, whereas two (67%) of the three patients with unfavorable results reported metamorphopsia. Patients with successful results showed a visual acuity of 20/25 or better in the affected eye and a significantly smaller difference in visual acuity between the two eyes than those patients with unfavorable surgical results (0.133 logarithm of the minimal angle of resolution for SBV(+) vs 0.675 logarithm of the minimal angle of resolution for SBV(-); P =.0255). CONCLUSIONS: The relatively low success for restoration of SBV indicates that strabismus surgery is recommended for patients whose difference in visual acuity between the two eyes is small and who have a high level visual acuity of the affected eye. 相似文献
175.
Evaluation of arteriovenous crossing sheathotomy for branch retinal vein occlusion by fluorescein videoangiography and image analysis 总被引:3,自引:0,他引:3
Yamaji H Shiraga F Tsuchida Y Yamamoto Y Ohtsuki H 《American journal of ophthalmology》2004,137(5):834-841
PURPOSE: We quantitatively evaluated the effects of arteriovenous (A/V) crossing sheathotomy on retinal circulation in patients with branch retinal vein occlusion (BRVO) accompanied by macular edema. DESIGN: Interventional case series. METHODS: In 18 consecutive patients (18 eyes) with BRVO accompanied by macular edema who underwent A/V crossing sheathotomy between August 1999 and April 2002, changes in retinal circulation after the surgery were evaluated by fluorescein videoangiography with a scanning laser ophthalmoscope and by image analysis using dye dilution technique. At a venule distal to the responsible A/V crossing site and a normal venule, the circulation time (T50) from the beginning of filling to 50% filling of the peak intensity was calculated. The time difference (DeltaT50) between T50 at the point on the affected venule and that at the point on the normal venule, which represents the filling delay at the venule distal to the A/V crossing site, was compared between before and early after the surgery. RESULTS: The preoperative DeltaT50 was 1.36 +/- 1.15 seconds (mean +/- SD), and the postoperative DeltaT50 was 0.72 +/- 0.77 seconds (P =.035, paired t test). In 11 of the 18 eyes, DeltaT50 decreased by 20% or more after the surgery. In the other 7 eyes, DeltaT50 was unchanged or slightly increased after the surgery. CONCLUSIONS: Although a randomized controlled study is needed to confirm the effectiveness of A/V crossing sheathotomy on visual function, this technique could be effective for improving the delay in perfusion in the affected venule. 相似文献
176.
177.
Purpose To evaluate the usefulness of the short-time Fourier transform (STFT) in the analysis of temporal congenital nystagmus characteristics.Methods We carried out an observational case series in patients with congenital nystagmus. An electronystagmogram (ENG) recording was performed for 300s in 13 consecutive subjects with congenital nystagmus (age: 7–68 years). Digitized ENG signals (12 bits, 100Hz) were divided into 2-s segments with a Hanning window, and a Fourier transform was carried out for each segment. The power spectrum obtained for each segment was graphically reconstructed as a function of time. The results were compared among the patients.Results Clear periodicity in the time-frequency distribution was observed in 3 of the 13 patients (23%). One of the three patients was diagnosed with periodic alternating nystagmus, but the other two patients showed periodicity without alternation of beat direction. No significant difference was observed in clinical characteristics, except for sex, between patients who showed periodicity and those who did not.Conclusions Some patients with congenital nystagmus showed clear periodicity in the nystagmus waveform without alternation of beat direction. The STFT is a useful tool to evaluate the temporal characteristics of congenital nystagmus in clinics. Jpn J Ophthalmol 2004;48:262–267 © Japanese Ophthalmological Society 2004An erratum to this article can be found at 相似文献
178.
A labdane-diterpene, austroinulin (1), together with several known flavonoids and sesquiterpenes were isolated from leaves of Blumea glomerata (Compositae). Austroinulin (1) and most of the flavonoids showed cytotoxicity against HeLa cells, while austroinulin (1) exhibited a cell cycle inhibition effect at the G1 stage at the concentration of 15.2 microg/mL (47.2 microM). The absolute configuration of 1 was revised as 5S,6R,7S,8S,9R,10R on the basis of the modified Mosher's method. 相似文献
179.
Eight 2-arylbenzofurans and an isoflavone isolated from medicinal plants were tested for their antimicrobial activities against vancomycin-resistant enterococci (VRE) and methicillin-resistant Staphylococcus aureus (MRSA). Among these compounds, six hydrophobic 2-arylbenzofurans (log P = 4.4-8.7) exhibited considerable antibacterial activity against five VRE strains(VanA-, VanB-, and VanC-phenotypes) (MICs = 3.13-6.25 microg/mL). Five compounds also showed antibacterial activity against ten MRSA strains (MIC80 = 3.13 microg/mL). 相似文献
180.
Goto S Asada S Fushiwaki Y Mori Y Tanaka N Umeda M Nakajima D Takeda K 《Journal of UOEH》2004,26(4):423-430
The tumor-promoting activities of 5 commercial compounds used in termiticides were measured by a cell-transformation assay employing Bhas 42 cells. Their initiating activities were also measured by the microsuspension assay employing S. typhimurium TA98 and TA100 strains. The results of the transformation assay confirmed the tumor-promoting activities of fenitrothion, silafluofen and bifenthrin. Furthermore, the mutagenicity of S-421 and fenitrothion were also confirmed. Consideration of 2-stage carcinogenesis suggests that concurrent use of and long-term exposure to these compounds that have tumor-promoting and initiator activity, and compounds exhibiting either type of activity individually should be avoided as much as possible. 相似文献