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991.
Keisuke Mori Kaname Kanai Gholam A Peyman Shin Yoneya 《Ophthalmic surgery, lasers & imaging》2007,38(2):142-147
BACKGROUND AND OBJECTIVE: To describe the biodistribution of a hydrophilic sensitizer, mono-L-aspartyl chlorin e6 (NPe6), in a primate model of choroidal neovascularization (CNV). MATERIALS AND METHODS: NPe6 (25 mg/kg) and indocyanine green (ICG, 15 mg/kg) were intravenously administered simultaneously in monkeys with laser-induced CNVs. Eyes were enucleated and examined by fluorescence microscopy immediately, 20 minutes, and 1, 4, and 24 hours after dye injection. RESULTS: Fluorescence peaked in retinal vessels immediately after dye administration; rapid washout began 1 hour postinjection. In contrast, experimental CNV demonstrated little fluorescence immediately after injection, with increased intensity at later time points. Peak dye fluorescence in CNV occurred 1 hour following dye injection. NPe6 fluorescence diminished rapidly and washed out completely by 24 hours. The dye accumulation and retention pattern of ICG dye resembled that of NPe6. CONCLUSIONS: This study demonstrated the selective accumulation of NPe6 photosensitizer and ICG dye within experimental CNV and rapid clearance from the circulation and retinochoroidal tissue. 相似文献
992.
Vivian Yvonne Shin William Ka Kei Wu Kent Man Chu Marcel Wing Leung Koo Helen Pui Shan Wong Emily Kai Yee Lam Emily Kin Ki Tai Chi Hin Cho 《Toxicological sciences》2007,96(1):21-29
We previously reported that nicotine promoted gastric cancer cell growth via upregulation of cyclooxygenase 2 (COX-2). In the present study, we further investigated whether beta-adrenoceptors, protein kinase C (PKC), and extracellular signal-regulated kinase-1/2 (ERK1/2) were involved in the modulation of COX-2 expression and cell proliferation by nicotine in AGS, a human gastric adenocarcinoma cell line. Results showed that nicotine dose dependently increased the phosphorylation of EKR1/2 and the expression of AP-1 subunits c-fos and c-jun. In this connection, the ERK1/2 inhibitor U0126 abrogated the upregulation of AP-1 and COX-2 as well as cell proliferation induced by nicotine. Moreover, nicotine induced the translocation of PKC-betaI from cytosol to membrane and increased the total levels of PKC expression. Inhibition of PKC by staurosporine attenuated nicotine-induced ERK1/2 phosphorylation and COX-2 expression. Furthermore, atenolol and ICI 118,551, a beta1- and beta2-adrenoceptor antagonist, respectively, reversed the stimulatory action of nicotine on the expression of PKC, ERK1/2 phosphorylation, and COX-2 together with cell proliferation. Collectively, these results suggest that nicotine stimulates gastric cancer cell growth through the activation of beta-adrenoceptors and the downstream PKC-betaI/ERK1/2/COX-2 pathway. 相似文献
993.
Hua Jin Seung-Hee Chang Cheng-Xiong Xu Ji-Young Shin Youn-Sun Chung Sung-Jin Park Yeon-Sook Lee Gil-Hwan An Kee-Ho Lee Myung-Haing Cho 《Toxicological sciences》2007,100(1):215-223
Inorganic phosphate (Pi) plays a key role in diverse physiological functions. Several studies indicate that Pi may affect lung cell development through Na/Pi cotransporter (NPT). Several NPT subtypes have been identified in mammalian lung, and considerable progress has been made in our understanding of their function and regulation. Therefore, current study was performed to elucidate the potential effects of high dietary Pi on lungs of developing mice. Our results clearly demonstrate that high dietary Pi may affect the lung of developing mice through Akt-related cap-dependent protein translation, cell cycle regulation, and angiogenesis. Our results support the hypothesis that Pi works as a critical signal molecule for normal lung growth and suggest that careful restriction of Pi consumption may be important in maintaining a normal development. 相似文献
994.
Ho-Jin Kang Im-Sook Song Ho Jung Shin Woo-Young Kim Choong-Hee Lee Joo-Cheol Shim Hong-Hao Zhou Sang Seop Lee Jae-Gook Shin 《Drug metabolism and disposition》2007,35(4):667-675
Genetic variants of three human organic cation transporter genes (hOCTs) were extensively explored in a Korean population. The functional changes of hOCT2 variants were evaluated in vitro, and those genetic polymorphisms of hOCTs were compared among different ethnic populations. From direct DNA sequencing, 7 of 13 coding variants were nonsynonymous single-nucleotide polymorphisms (SNPs), including four variants from hOCT1 (F160L, P283L, P341L, and M408V) and three from hOCT2 (T199I, T201M, and A270S), whereas 6 were synonymous SNPs. The linkage disequilibrium analysis presented for three independent LD blocks for each hOCT gene showed no significant linkage among all three hOCT genes. The transporter activities of MDCK cells that overexpress the hOCT2-T199I, -T201M, and -A270S variants showed significantly decreased uptake of [(3)H]methyl-4-phenylpyridinium acetate (MPP(+)) or [(14)C]tetraethylammonium compared with those cells that overexpress wild-type hOCT2, and the estimated kinetic parameters of these variants for [(3)H]MPP(+) uptake in oocytes showed a 2- to 5-fold increase in K(m) values and a 10- to 20-fold decrease in V(max) values. The allele frequencies of the five functional variants hOCT1-P283L, -P341L, and hOCT2-T199I, -T201M, and -A270S were 1.3, 17, 0.7, 0.7, and 11%, respectively, in a Korean population; the frequency distributions of these variants were not significantly different from those of Chinese and Vietnamese populations. These findings suggest that genetic variants of hOCTs are not linked among three genes in a Korean population, and several of the hOCT genetic variants cause decreased transport activity in vitro compared with the wild type, although the clinical relevance of these variants remains to be evaluated. 相似文献
995.
996.
A. M. Abd El-Aty Syed Sher Shah Bo-Mee Kim Jeong-Heui Choi Hee-Jung Cho Hee-Yi Byung-Joon Chang Ho-Chul Shin Kang Bong Lee Minoru Shimoda Jae-Han Shim 《Archives of pharmacal research》2008,31(11):1425-1435
Danggui is one of the most popular herbal medicines consumed by patients in different clinical settings in Asian countries.
In this study, the two major pyranocoumarin compounds extracted from the Korean Angelica gigas root decursin (DC) and decursinol angelate (DA) were examined in vitro with regard to their abilities to inhibit hepatic CYP1A1/2, CYP2D15, and CYP3A12 catalytic activities in canine liver microsomes.
The two components were capable of inhibiting CYP1A1/2, CYP2D15, and CYP3A12 catalytic activities, but the potencies varied.
DC and DA selectively and noncompetitively inhibited CYP1A1/2 activity, with K
i
values of 90.176 and 67.560 μM, respectively. On the other hand, they exhibited slight inhibitory effects on CYP2D15 and
CYP3A12 with K
i
values of 666.180 and 872.502 μM, 990.500 and 909.120 μM (1’hydroxymidazolam, MDZ1’H), and 802.800 and 853.920 μM (4-hydroxymidazolam,
MDZ4H), respectively. Additionally, they showed increased inhibition after preincubation, which suggests the involvement of
a mechanism-based inhibition. In sum, this in vitro data should be heeded as a signal of possible in vivo interactions. The use of human liver preparations would considerably strengthen the practical impact of the data generated
from this study.
The two authors contributed equally to this paper. 相似文献
997.
Seung-Il Jeong Beng Zhou Jin-Beom Bae Nam-Seok Kim Sun-Geun Kim Jin Kwon Dae-Keun Kim Tae-Yong Shin Hoon Jeon Jong-Phil Lim Hongjun Kim Ho Kyoung Kim Chan-Ho Oh 《Archives of pharmacal research》2008,31(11):1399-1404
Methanol extracts of the root of Dipsacus asper Wall (Dipsacaceae) were found to exhibit apoptosis-inducing activities in U937 (human monocyte-like histiocytic) cells. Investigation
of the active n-BuOH fraction led to the isolation of akebia saponin D (ASD). Structure was established by spectroscopic methods. Treatment
of U937 cells with ASD induced apoptosis in a dose dependent manner. ASD exerted strong cytotoxicity against human and murine
leukemia cells. It is significantly increased the subG1 cell population and expression of p53 and Bax gene. And also ASD enhanced
NO production from RAW264.7 macrophage cells. Taken together, these results strongly indicate that ASD may exert apoptosis-inducing
activity via induction of apoptosis through activation chiefly via the nitric oxide and apoptosis-related p53 and Bax gene expression.
These data provide scientific evidence that Dipsacus asper Wall can be useful as a chemopreventive agent. 相似文献
998.
Ho Sun Song Tae Wook Park Uy Dong Sohn Yong Kyoo Shin Byung Chul Choi Chang Jong Kim Sang Soo Sim 《The Korean journal of physiology & pharmacology》2008,12(6):343-347
This study was carried out to investigate the wound healing effect of caffeic acid in skin-incised mice. Caffeic acid showed significant effects on anti-inflammatory activity and wound healing, such as myeloperoxidase activity, lipid peroxidation, phospholipase A2 activity and collagen-like polymer synthesis, in incised-wound tissue. On the other hand, it significantly stimulated collagen-like polymer synthesis in NIH 3T3 fibroblast cells, while inhibited both silica-induced reactive oxygen species generation and melittin-induced arachidonic acid release and PGE2 production in Raw 264.7 cells, and histamine release in RBL 2H3 cells stimulated by melittin or arachidonic acid. Therefore, caffeic acid appears to have a potent antioxidant and anti-inflammatory effect in cell culture system, which may be related to wound healing in skin-incised mice. 相似文献
999.
Eun Ji Lee Ki Ho Park Dong Myung Kim Young Cheol Yoo Shin Hee Kang Yu Jeong Kim 《Japanese journal of ophthalmology》2008,52(6):500-503
Purpose To compare rebound tonometer and cannulation as methods for measuring intraocular pressure (IOP) in rats.
Methods The accuracy of the TonoLab rebound tonometer was determined in eight cannulated rat eyes. IOP was manipulated by changing
air pressure from 20 to 100 mmHg at 10-mmHg intervals, and the IOP was measured with the rebound tonometer at each level.
The average value of three repeated pressure readings was recorded. Correlation analysis and comparison with the Bland and
Altman method were performed. The intraclass correlation coefficient was calculated to assess intraoperator variability.
Results The IOP values measured with the TonoLab rebound tonometer were well correlated with the actual IOP (r
2 = 0.963, P = 0.01). The mean of the difference between the rebound tonometer and actual (cannulation) IOP was 7.41 ± 7.87%. The intraclass
correlation coefficient was 0.9, indicating low intraoperator variability.
Conclusions The rebound tonometer showed high accuracy and reliability for IOP measurement in rat eyes. 相似文献
1000.
Influence of the delivery systems using a microneedle array on the permeation of a hydrophilic molecule, calcein. 总被引:1,自引:0,他引:1
Jae-Ho Oh Hyoun-Hyang Park Ki-Young Do Manhee Han Dong-Hun Hyun Chang-Gyu Kim Chang-Hyeon Kim Seung S Lee Sung-Joo Hwang Sang-Chul Shin Cheong-Weon Cho 《European journal of pharmaceutics and biopharmaceutics》2008,69(3):1040-1045
Despite the advantages of drug delivery through the skin, such as easy accessibility, convenience, prolonged therapy, avoidance of the liver first-pass metabolism and a large surface area, transdermal drug delivery is only used with a small subset of drugs because most compounds cannot cross the skin at therapeutically useful rates. Recently, a new concept was introduced known as microneedles and these could be pierced to effectively deliver drugs using micron-sized needles in a minimally invasive and painless manner. In this study, biocompatible polycarbonate (PC) microneedle arrays with various depths (200 and 500mum) and densities (45, 99 and 154ea/cm(2)) were fabricated using a micro-mechanical process. The skin permeability of a hydrophilic molecule, calcein (622.5D), was examined according to the delivery systems of microneedle, drug loading, depth of the PC microneedle, and density of the PC microneedle. The skin permeability of calcein was the highest when the calcein gel was applied to the skin with the 500mum-depth PC microneedle, simultaneously. In addition, the skin permeability of calcein was the highest when 0.1g of calcein gel was coupled to the 500mum-depth PC microneedle (154ea/cm(2)) as well as longer microneedles and larger density of microneedles. Taken together, this study suggests that a biocompatible PC microneedle might be a suitable tool for transdermal drug delivery system of hydrophilic molecules with the possible applications to macromolecules such as proteins and peptides. 相似文献