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991.
Purpose: We investigated the relationship between the progression of visual field defect and clinical factors in patients with normal-tension glaucoma (NTG).Subjects and Methods: Forty-eight eyes of 48 NTG patients undergoing more than 5-year follow-up were enrolled in this study. Their visual field defects ranged between Aulhorn's classification stage 2 and 4, and mean deviation (MD) more than -10 dB measured by Humphrey Field Analyzer (HFA). End points of this follow-up study were defined as follows: in HFA STATPAC 2 glaucoma change probability analysis, more than 5 points which significantly deteriorated at P <.05 were found at 2 consecutive examinations (Criterion 1) or a significant decrease in MD value at P <.025 was encountered at one examination or in MD value at P <.05 at consecutive examinations (Criterion 2).Results: During the follow-up period, 18 eyes of 48 patients satisfied Criterion 1 and 21 eyes Criterion 2. There were no significant differences in clinical factors between patients with progression and without progression. By multiple logistic regression analysis, minimum flow velocity of central retinal artery (CRA) showed significant relation (odds ratio for a 1 cm/sec rise = 0.2215; 95% confidence interval: 0.0530-0.9253) to progression of visual field defect in Criterion 1, and minimum flow velocity of CRA (odds ratio for a 1 cm/sec rise = 0.2099; 95% confidence interval: 0.0506-0.8712) and cholesterol (odds ratio for a 1 cm/dl rise = 1.0332; 95% confidence interval: 0.4096-2.6064) showed significant relation in Criterion 2.Conclusion: These results suggests that vascular risk factors of ocular blood flow may play a role in the progression of visual field defects in NTG patients. 相似文献
992.
993.
Characterization of (+/-)-bufuralol hydroxylation activities in liver microsomes of Japanese and Caucasian subjects genotyped for CYP2D6 总被引:1,自引:0,他引:1
Twenty-four genetic polymorphisms in the CYP2D6 gene were analysed in liver DNA samples of 39 Japanese and 44 Caucasians and compared with CYP2D6 protein levels and bufuralol 1'- and 6-hydroxylation activities in liver microsomes of these human samples. We detected 13 types of CYP2D6 genetic polymorphisms and classified these into 20 genotypes; nine types were found in Japanese and 14 types in Caucasian samples. CYP2D6*10B, but not CYP2D6*10A, was the most frequent (34.6%) in Japanese. In Caucasians, several CYP2D6 polymorphisms including CYP2D6*4, *4D, *4E, *4L, *3, *9, *5 and *2E (frequencies of 6.8, 3.4, 4.5, 9.1, 1.1, 2.3, 2.3 and 4.5%, respectively) were detected. A Caucasian having CYP2D6*3/*5 had a protein with slower gel mobility (immunoblotting with anti-CYP2D6 antibody) and very low activity for bufuralol 1'-hydroxylation. Five Caucasian samples (CYP2D6*4/*4, *4/*4L, or *4D/*4L) had no measurable CYP2D6 protein and very low bufuralol 1'-hydroxylation activities. Seven Japanese subjects with CYP2D6*10B/*10B had CYP2D6 protein at levels of approximately 20% of those present in humans with CYP2D6*1 and *2 and catalysed bufuralol 1'-hydroxylation at low rates. Kinetic analysis of bufuralol 1'- and 6-hydroxylation indicates that (i) the Km values for 1'-hydroxylation were lower in individuals with CYP2D6*1/*1, *1/*2, *1/*2X2, and *2/*2 than those with CYP2D6*4/*4, *4/*4L, *4D/*4L, or *10B/*10B and Vmax values tended to be higher in the former groups (*1, *2), and (ii) individuals with heterozygous CYP2D6*1/*4D, *1/*4L, and *1/*5 had relatively high Vmax/Km ratios, whereas individuals with heterozygous CYP2D6*1/*9, *2/4D, *2/*5, *2/*10B, *2E/*4E, *3/*5, *4L/*9, and *10B/*39 had lower Vmax/Km ratios for bufuralol 1'-hydroxylation. Quinidine inhibited bufuralol 1'-hydroxylation in liver microsomes, particularly at low substrate concentrations, in individuals with CYP2D6*1/*1, and 1/1*2, but not those with CYP2D6*4/*4 and very slightly in individuals with CYP2D6*10B/*10B. The latter two groups were found to be more sensitive to alpha-naphthoflavone than the former groups, indicative of the contribution of CYP1A2. These results support the view that CYP2D6*3, *4, *4D, and *4L are major genotypes producing poor metabolizer phenotypes in CYP2D6 in Caucasians, whereas CYP2D6*10B is a major factor in decreased CYP2D6 protein expression and catalytic activities in Japanese. 相似文献
994.
Matsuda H Yamazaki M Matsuo K Asanuma Y Kubo M 《Biological & pharmaceutical bulletin》2001,24(3):259-263
The aqueous ethanol extract of Myricae Cortex (bark of Myrica rubra Sieb. et Zucc., Myricaceae) showed in vitro testosterone 5alpha-reductase inhibitory activity and in vivo anti-androgenic activity using growth of flank organ in castrated Syrian hamsters and/or hair regrowth after shaving in testosterone-treated C57Black/6CrSlc mice. Three constituents, myricanone, myricanol, and myricetin were identified as the main active principles. 相似文献
995.
Spatial and temporal collagen gene expression in lumbar intertransverse fusion in the rabbit 总被引:3,自引:0,他引:3
Suzuki H Takahashi K Yamagata M Shimizu S Moriya H Yamazaki M 《The Journal of bone and joint surgery. British volume》2001,83(5):760-766
We have examined the process of fusion of the intertransverse processes and bone graft in the rabbit by in situ hybridisation and evaluated the spatial and temporal expression of genes encoding pro-alpha1 (I) collagen (COL1A1), pro-alpha1 (II) collagen (COL2A1) and pro-alphal (X) collagen (COL10A1). Beginning at two weeks after operation, osteogenesis and chondrogenesis occurred around the transverse process and the grafted bone at the central portion of the area of the fusion mass. Osteoblasts and osteocytes at the newly-formed woven bone expressed COL1A1. At the cartilage, most chondrocytes expressed COL2A1 and some hypertrophic chondrocytes COL10A1. In some regions, co-expression of COL1A1 and COL2A1 was observed. At four weeks, such expressions for COLlA1, COL2A1 and COL10A1 became prominent at the area of the fusion mass. From four to six weeks, bone remodelling progressed from the area of the transverse processes towards the central zone. Osteoblasts lining the trabeculae expressed a strong signal for COL1A1. At the central portion of the area of the fusion mass, endochondral ossification progressed and chondrocytes expressed COL2A1 and COL10A1. Our findings show that the fusion process begins with the synthesis of collagens around the transverse processes and around the grafted bone independently. Various spatial and temporal osteogenic and chondrogenic responses, including intramembranous, endochondral and transchondroid bone formation, progress after bone grafting at the intertransverse processes. Bone formation through cartilage may play an important role in posterolateral spinal fusion. 相似文献
996.
Hori Y Hoshino J Yamazaki C Sekiguchi T Miyauchi S Horie K 《Japanese journal of pharmacology》2001,85(2):155-160
Chondroitin sulfate (CS) is currently marketed as a therapeutic drug for neurodynia, lumbago and arthrodynia. Recently, many clinical studies have demonstrated the therapeutic effects of orally administered CS against diseases with inflammation. Furthermore, these reports suggest CS plays an important role in the protection of the base of ulcers and has anti-inflammatory activity. We investigated the effects of CS against dextran sulfate sodium (DSS)-induced rat colitis. Rats were given 3% DSS solution for 10 days ad libitum. CS and 5-aminosalicylic acid (5-ASA) were orally administered daily. The doses of the CS groups were 20 or 100 mg/kg and that for the 5-ASA group was 100 mg/kg. Evaluations were made of bloody stools, areas of erosion and hematological data. CS improved the symptoms of bloody stools, erosion and increase of white blood cells. Especially, CS (100 mg/kg) group showed markedly more improvement than the 5-ASA group. We think that the major mechanism of the therapeutic effects of CS are the prevention of tissue damage by the protection of digestive mucosa and anti-inflammatory effects. Therefore, CS may have therapeutic value for alimentary tract diseases such as inflammatory bowel disease or ulcer. 相似文献
997.
Yamazaki S Hayashi M Toth LN Ozawa N 《Xenobiotica; the fate of foreign compounds in biological systems》2001,31(1):25-31
1. Bropirimine (2-amino-5-bromo-6-phenyl-4-pyrimidinone) is a member of a class of antineoplastic agents that are administered concomitantly or sequentially with anticancer 5-fluorouracil (5-FU) prodrugs in clinical patients. Interactions between bropirimine and 5-fluorouracil (5-FU) were investigated on dihydropyrimidine dehydrogenase (DPD) activity, the rate-limiting enzyme of 5-FU metabolism, in human liver cytosol. Apparent DPD activity was determined by measuring the recovery of [14C]5-FU by HPLC. 2. The apparent activity of 5-FU metabolism (2.1-100 microM) showed a linear relationship in the Eadie-Hofstee plot in the pooled cytosol, suggesting that a single enzyme is responsible for apparent 5-FU metabolism. Km and Vmax were estimated to be 23 microM and 0.32 nmol min(-1) mg(-1) protein, respectively. Apparent DPD activity for 5-FU (25 microM) in the cytosol from 12 individual donors ranged from 0.017 to 0.39 (0.16 +/- 0.12) nmol min(-1) mg(-1) protein, indicating a large intersubject variance. 3. The suicidal inactivators of the DPD enzyme, (E)-5-(2-bromovinyl)uracil and 5-bromouracil (6.3-50 microM), illustrated concentration-dependent inhibition on DPD activity. Isocytosine (6.3-100 microM), used as a negative control, did not affect DPD activity. Bropirimine (6.3-100 microM) also did not show any inhibition of DPD activity. Therefore, bropirimine is unlikely to cause increases in 5-FU levels in clinical patients after co-administration of bropirimine with 5-FU prodrugs. 相似文献
998.
Atypical adenomatous hyperplasia of the lung in autopsy cases 总被引:2,自引:0,他引:2
Yokose T Doi M Tanno K Yamazaki K Ochiai A 《Lung cancer (Amsterdam, Netherlands)》2001,33(2-3):155-161
BACKGROUND: Atypical adenomatous hyperplasia (AAH) is a possible precursor lesion of adenocarcinoma of the lung, but very few reports of AAH have focused on the autopsy lung. METHODS: We intended to clarify the characteristics of AAH in the general population by using 207 autopsy cases, ranging in age from 0 to 90 years old. RESULTS: A total of 179 eligible cases (86.5%) and 1265 tissue slides (7.0 per case) was examined independently by two pathologists. One hundred seventy-nine autopsy cases consisted of 125 males and 54 females, whose median ages were 38 (range 0-90) and 31 (range 0-81) years old, respectively. AAH was microscopically found in five of 179 autopsy cases (2.8%). The male/female ratio was 5/0 and age distribution was 52-63 years of age (median 57). One of five cases with AAH harbored esophageal carcinoma, but the others had no present or previous malignant neoplasm. One of five lesions was high grade and the others were low grade. All five cases showed positive immunoreactivity for proSP-C, a type II pneumocytes marker, but not for p53, Ki-67 or CEA. CONCLUSIONS: The incidence of AAH was very low in the general autopsy cases, as compared with the previously reported surgically resected lung and senile autopsy cases, and AAH seems to occur after middle age in general. 相似文献
999.
Acute up-regulation of brain-derived neurotrophic factor expression resulting from experimentally induced injury in the rat spinal cord 总被引:15,自引:0,他引:15
Ikeda O Murakami M Ino H Yamazaki M Nemoto T Koda M Nakayama C Moriya H 《Acta neuropathologica》2001,102(3):239-245
Brain-derived neurotrophic factor (BDNF), a member of the nerve growth factor family of trophic factors, has multiple functions including a role in the promotion of neuronal survival and nerve fiber elongation in both the central and the peripheral nervous systems. We assessed the expression of endogenous BDNF following an experimentally induced compression injury to the spinal cord. Expression of BDNF mRNA was increased following the spinal cord injury; reaching maximum levels 24 h after the injury. Expression of BDNF mRNA returned to the levels observed in sham-operated control animals within 3 days of the injury. Using the in situ hybridization technique, we observed a wide distribution of BDNF expression among the different cell types in the spinal cord, including motor and sensory neurons, and in glia cells, including astrocytes. We also observed expression of BDNF in putative macrophages and/or microglia; however, this effect was not observed until day 7 following spinal cord injury. These results suggest that BDNF is synthesized in both neurons and astrocytes during the acute response to injury to the spinal cord, functioning in a mainly neuroprotective role. This is followed by a later phase of expression in which BDNF is produced by macrophages and/or microglia, apparently functioning in a restorative capacity. 相似文献
1000.
Effects of ketamine on voltage-dependent calcium currents and membrane potentials in single bullfrog atrial cells 总被引:1,自引:0,他引:1
Purpose. This study was undertaken to assess the effect of ketamine on L-type calcium channel current (ICa) and membrane action potential in the bullfrog single atrial myocyte.
Methods. Bullfrog single atrial myocytes were prepared by enzymatic dispersion. Whole-cell voltage-clamp technique and current clamp
technique were used to monitor ICa, membrane resting potential, and action potential.
Results. Ketamine (10−5–10−3 M) showed dose-dependent inhibition of ICa in a reversible manner. The 50% inhibitory concentration (IC50) of ketamine on ICa was estimated to be 0.92 × 10−5 M. Use-dependent block of ICa was not observed. The resting membrane potential was depolarized at a high concentration (10−4 M) of ketamine. Reduction of the plateau phase and prolonged duration of the action potential were observed in the presence
of a high concentration of ketamine (10−4 M).
Conclusion. Ketamine has an inhibitory effect on ICa in the bullfrog single atrial myocyte, and a high dose (10−4 M) of ketamine prolonges the duration of the action potential. The mechanism of inhibition of ICa seems to be a direct effect on the L-type calcium channel, not like an open channel blocker.
Received: October 2, 2000 / Accepted: February 19, 2001 相似文献