201
|
Mina MF, Ania F, Baltá Calleja FJ, Asano T. Microhardness studies of PMMA/natural rubber blends. J Appl Polym Sci 2003. [DOI: 10.1002/app.13246] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
|
202
|
Aoyama H, Shirato H, Chang T, Ushikoshi S, Asano T, Kudo K, Miyasaka K. The use of MR angiography and CT angiography in stereotactic radiosurgery of intracranial AVMs. Int J Radiat Oncol Biol Phys 2003. [DOI: 10.1016/s0360-3016(03)01285-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
|
203
|
Shishido T, Clarke IC, Williams P, Boehler M, Asano T, Shoji H, Masaoka T, Yamamoto K, Imakiire A. Clinical and simulator wear study of alumina ceramic THR to 17 years and beyond. ACTA ACUST UNITED AC 2003; 67:638-47. [PMID: 14528462 DOI: 10.1002/jbm.b.10048] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Three THAs with cementless monolithic alumina ceramic sockets and cementless Co-alloy stems were retrieved because of aseptic loosening after 17 and 24 years. At revision heads and cups were marked for orientation. Maps were drawn of wear patterns with the use of light microscopy and surveyed by SEM. In a simulator experiment 28-mm-diameter alumina heads and liners were used. The cups were mounted inverted in a hip simulator and run with calf serum as the lubricant. The hip loads were 2 kN maximum and a 1-Hz frequency for 20 million cycles. Wear severity was classified into five grades. In retrieved implants, SEM analysis showed that the main wear zones (MWZ) had Grade 4 wear. The peripheral wear zones (PWZ) showed grain pull-out regions (Grade 5 wear). These corresponded to neck-socket impingement and head-acetabular cup separation. Gray was due to transferred CoCr particles from the stem. In the simulator study, the MWZ had only localized areas of grain pull out surrounded by polished surface regions (Grade 4 wear) at 20 million cycles; stripe wear was not seen. The alumina ceramic bearings proved excellent up to 22 years in simulator studies and clinical studies. However, microseparation kinematics would be necessary in the simulator to duplicate the more peripheral wear zones.
Collapse
|
204
|
Komiyama O, Asano T, Suzuki H, Kawara M, Wada M, Kobayashi K, Ohtake S. Mandibular condyle movement during mastication of foods. J Oral Rehabil 2003; 30:592-600. [PMID: 12787456 DOI: 10.1046/j.1365-2842.2003.01042.x] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
This study evaluated the mandibular condyle displacement on the working side while masticating certain foods with different textures. For referencing the mandibular condyle movement, the range of voluntary border movement of the mandibular condyle was determined based on the analysis of the sagittal, left lateral and right lateral border motion using Posselt's figure. The test foods consisted of cheese, peanuts, and beef jerky. During mastication of cheese and peanuts, the amount of displacement of the mandibular condyle in all directions was within the range of border movement. Significant posterior and superior shifts of the mandibular condyle were observed during mastication of beef jerky, compared with the findings obtained during border movement. Accordingly, it is suggested that prolonged mastication of hard fibrous foods, may stimulate the temporomandibular joint structure and mandibular dysfunction patients should limit their intake of such foods.
Collapse
|
205
|
Kishi R, Miura T, Kihara H, Asano T, Shibata M, Yosomiya R. Fast pH-thermo-responsive copolymer hydrogels with micro-porous structures. J Appl Polym Sci 2003. [DOI: 10.1002/app.11996] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
|
206
|
Mori M, Itabe H, Saijo M, Asano T, Fujimoto Y, Yoshizumi M, Takano T. 4P-0959 PC-choleserol complex correlates from cell rupture. ATHEROSCLEROSIS SUPP 2003. [DOI: 10.1016/s1567-5688(03)91217-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
|
207
|
Matsui Y, Asano T, Kenmochi T, Tokoro Y, Jingu K, Maruyama M, Akutsu N, Miyauchi H, Itoh T, Saito T, Ochiai T. Cytoprotective effect of hepatic cell pretreatment with 15-deoxyspergualin to prevent warm ischemic reperfusion injuries in rats. Transplant Proc 2002; 34:2674-6. [PMID: 12431570 DOI: 10.1016/s0041-1345(02)03371-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
|
208
|
Saitoh T, Fukushima Y, Otsuka H, Hirakawa J, Mori H, Asano T, Ishikawa T, Katsube T, Ogawa K, Ohkawa S. Effects of rabeprazole, lansoprazole and omeprazole on intragastric pH in CYP2C19 extensive metabolizers. Aliment Pharmacol Ther 2002; 16:1811-7. [PMID: 12269976 DOI: 10.1046/j.1365-2036.2002.01348.x] [Citation(s) in RCA: 54] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
AIM To investigate the inhibitory effects on gastric acid secretion of three proton pump inhibitors, omeprazole, lansoprazole and rabeprazole, using a three-way crossover design in healthy Helicobacter pylori-negative,S-mephenytoin 4'-hydroxylase (CYP2C19) homo- and hetero-extensive metabolizers. METHODS Eight healthy Japanese male volunteers were enrolled. After the administration of rabeprazole (10 mg/day), lansoprazole (30 mg/day) or omeprazole (20 mg/day), intragastric pH monitoring was commenced from 24 h before the first proton pump inhibitor dose, and continued for days 1-3 after proton pump inhibitor administration. The pH electrode was used for 48 h and changed just before pH monitoring on day 2. RESULTS For the administration of 10 mg/day rabeprazole, the mean ratios of the 24-h pH > or = 3 holding time were 5.7 +/- 1.1%,13.6 +/- 2.2%, 35.3 +/- 2.7% and 62.8 +/- 3.1% for the pre-treatment day and days 1, 2 and 3, respectively. The same ratios for lansoprazole (30 mg/day) were 5.7 +/- 0.7%, 7.4 +/- 1.5%, 13.6 +/- 3.4% and 26.6 +/- 4.9%; the same ratios for 20 mg/day omeprazole were 5.9 +/- 0.9%, 6.1 +/- 1.2%, 11.4 +/- 2.8% and 16.4 +/- 4.6%. The mean ratio of the 24-h pH > or = 3 holding time of days 1-3 increased significantly compared to the pre-treatment day (P < 0.01) with the administration of rabeprazole and lansoprazole. The magnitude of inhibition of gastric acid secretion after rabeprazole administration was stronger than that after lansoprazole. A significant elevation of the mean ratio of the 24-h pH > or = 3 holding time was demonstrated on days 2 and 3 with omeprazole (P < 0.01). CONCLUSIONS In H. pylori-negative CYP2C19 extensive metabolizers, rabeprazole (10 mg/day) shows a faster onset of rising intragastric pH and a stronger inhibition of gastric acid secretion than do lansoprazole (30 mg/day) or omeprazole (20 mg/day).
Collapse
|
209
|
Asano TK, McLeod RS, Blitz M, Butts C, Kneteman N, Bigam D, Oosthuizen JFM, Phang PT, Gouthro D, Ravid A, Liu M, O'Connor BI, MacRae HM, Cohen Z, McLeod RS, Al-Obeed O, Penning J, Stern HS, Colquhoun P, Nogueras J, Dipasquale B, Petras J, Wexner S, Woodhouse S, Raval MJ, Heine JA, May GR, Bass S, Brown CJ, MacLean AR, Asano T, Cohen Z, MacRae HM, O'Connor BI, McLeod RS, Asano TK, Toma D, Stern HS, McLeod RS, Irshad K, Ghitulescu GA, Gordon PH, MacLean AR, Lilly L, Cohen Z, O'Connor B, McLeod RS, Ravid A, O'Connor BI, Liu M, MacRae HM, Cohen Z, McLeod RS, St Germaine RL, de Gara CJ, Fox R, Kenwell Z, Blitz S, Wong JT, Mc-Mulkin HM, Porter GA, Jayaraman S, Gray D, Burpee SE, Schlachta CM, Mamazza J, Pace K, Poulin EC, Freeman J, Tranqui P, Trottier D, Bodurtha A, Sarma A, Bheerappa N, Sastry RA, de Gara CJ, Hanson J, Hamilton S, Taylor MC, Haase E, Stevens J, Rigo V, Richards J, Bigam DL, Cheung PY, Burpee SE, Schlachta CM, Mamazza J, Pace K, Poulin EC, Grace DM, Gupta S, Sarma A, Bheerappa N, Radhakrishna P, Sastry RA, Malik S, Duffy P, Schulte P, Cameron R, Pace KT, Dyer S, Phan V, Poulin E, Schlachta C, Mamazza J, Stewart R, Honey RJ, Kanthan R, Kanthan SC, Jayaraman S, Aarts MA, Solomon MJ, McLeod RS, Ong S, Pitt D, Stephen W, Latulippe J, Girotti M, Bloom S, Pace K, Dyer S, Stewart R, Honey RJ, Poulin E, Schlachta C, Mamazza J, Furlan JC, Rosen IB, Asano TK, Haigh PI, McLeod RS, Al Saleh N, Taylor B, Karimuddin AA, Marschall J, McFadden A, Pollett WG, Dicks E, Tranqui P, Trottier D, Freeman J, Bodurtha A, Urbach DR, Bell CM, Austin PC, Cleary SP, Gyfe R, Greig P, Smith L, Mackenzie R, Strasberg S, Hanna S, Taylor B, Langer B, Gallinger S, Marschall J, Nechala P, Chibbar R, Colquhoun P, Zhou J, Lee TDG, Meneghetti AT, McKenna GJ, Owen D, Scudamore CH, McMaster RM, Chung SW, Aarts MA, Granton J, Cook DJ, Bohnen JMA, Marshall JC, Colquhoun P, Weiss E, Efron J, Nogueras J, Vernava A, Wexner S, Poulin EC, Schlachta CM, Burpee SE, Pace KT, Mamazza J, Rosen IB, Furlan JC, Charghi R, Schricker T, Backman S, Rouah F, Christou NV, Obayan A, Keith R, Juurlink BHJ, Skaro AI, Liwski RS, Zhou J, Lee TDG, Hirsch GM, Powers KA, Khadaroo RG, Papia G, Kapus A, Rotstein OD, Furlan JC, Rosen IB, Stratford AFC, George RL, VanManen L, Klassen DR, Feldman LS, Mayrand S, Mercier L, Stanbridge D, Fried GM, Nanji SA, Hancock WW, Anderson C, Shapiro AMJ, Butter A, Martins L, Taylor B, Ott MC, Rycroft K, Wall WJ, Burpee SE, Schlachta CM, Mamazza J, Pace K, Poulin EC, Taylor MC, Christou NV, Jarand J, Sylvestre JL, McLean APH, Behzadi A, Tan L, Unruh H, Brandt MG, Darling GE, Miller L, Seely AJE, Maziak DE, Gunning D, Do MT, Bukhari M, Shamji FM, Abdurahman A, Darling G, Ginsberg R, Johnston M, Waddell T, Keshavjee S, Cuccarolo G, Charyk-Stewart T, Inaba K, Malthaner R, Gray D, Girotti M, Grondin SC, Tutton SM, Sichlau MJ, Pozdol C, McDonough TJ, Masters GA, Ray DW, Liptay MJ. Abstracts of presentations to the Annual Meetings of the Canadian Society of Colon and Rectal Surgeons Canadian Association of General Surgeons Canadian Association of Thoracic Surgeons: Canadian Surgery Forum, London, Ont., Sept. 19 to 22, 2002. Can J Surg 2002; 45:3-26. [PMID: 37381180] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/30/2023] Open
|
210
|
Hanazono Y, Nagashima T, Takatoku M, Shibata H, Ageyama N, Asano T, Ueda Y, Dunbar CE, Kume A, Terao K, Hasegawa M, Ozawa K. In vivo selective expansion of gene-modified hematopoietic cells in a nonhuman primate model. Gene Ther 2002; 9:1055-64. [PMID: 12140733 DOI: 10.1038/sj.gt.3301781] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2001] [Accepted: 04/02/2002] [Indexed: 11/09/2022]
Abstract
A major problem limiting hematopoietic stem cell (HSC) gene therapy is the low efficiency of gene transfer into human HSCs using retroviral vectors. Strategies, which would allow in vivo expansion of gene-modified hematopoietic cells, could circumvent the problem. To this end, we developed a selective amplifier gene (SAG) consisting of a chimeric gene composed of the granulocyte colony-stimulating factor (G-CSF) receptor gene and the estrogen receptor gene hormone-binding domain. We have previously demonstrated that primary bone marrow progenitor cells transduced with the SAG could be expanded in response to estrogen in vitro. In the present study, we evaluated the efficacy of the SAG in the setting of a clinically applicable cynomolgus monkey transplantation protocol. Cynomolgus bone marrow CD34(+) cells were transduced with retroviral vectors encoding the SAG and reinfused into each myeloablated monkey. Three of the six monkeys that received SAG transduced HSCs showed an increase in the levels of circulating progeny containing the provirus in vivo following administration of estrogen or tamoxifen without any serious adverse effects. In one monkey examined in detail, transduced hematopoietic progenitor cells were increased by several-fold (from 5% to 30%). Retroviral integration site analysis revealed that this observed increase was polyclonal and no outgrowth of a dominant single clonal population was observed. These results demonstrate that the inclusion of our SAG in the retroviral construct allows selective in vivo expansion of genetically modified cells by a non-toxic hormone treatment.
Collapse
|
211
|
Suzuki S, Tadakuma T, Kunitomi M, Takayama E, Sato M, Asano T, Nakamura H, Hayakawa M. Liposome-mediated gene therapy using HSV-TK/ganciclovir under the control of human PSA promoter in prostate cancer cells. Urol Int 2002; 67:216-23. [PMID: 11598449 DOI: 10.1159/000050991] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
To more accurately determine the tissue-specific expression of the target gene in prostate cancer cells, we introduced the enhancer element (-4,777 to -3,934; PSAR) and the promoter region (PSAP) of the prostate-specific antigen (PSA) gene. Furthermore, to elucidate the advantages of using liposomes as a gene carrier, we screened more than 20 liposome preparations in this study. The 5' upstream region of PSA gene (PSARPSAP) was conjugated to either the chloramphenicol acetyltransferase (CAT) gene or herpes simplex virus thymidine kinase (TK) gene, and the transfection of these plasmids was carried out using cationic liposomes, DMRIE-C (Gibco) or LipoTAXI (Stratagene). The expression of CAT activity was clearly observed when PSARPSAP-CAT plasmid was transfected into PSA-positive LNCaP cells, whereas no CAT activity was detected in PSA-negative DU145 cells or bladder carcinoma T24 cells. The CAT activity increased after the addition of testosterone. We then evaluated the therapeutic effect of the PSARPSAP-TK plasmid in vitro. When PSARPSAP-TK plasmid was transfected and ganciclovir was added to the medium, the growth of LNCaP cells was inhibited, while no growth inhibition was observed in DU145 cells. Furthermore, this inhibitory effect was observable even when the cells were cultured in a medium supplemented with dialyzed fetal bovine serum. These results suggest that the liposome-mediated transfection of PSARPSAP-TK appears to be a potentially effective approach for selecting the optimal treatment for tumor cells producing PSA even with the low androgen levels seen in patients treated by anti-androgen therapy.
Collapse
|
212
|
Saitoh T, Fukushima Y, Otsuka H, Ishikawa M, Tamai M, Takahashi H, Mori H, Asano T, Anai M, Ishikawa T, Katsube T, Ogawa K, Kajiwara T, Omata M, Ohkawa S. Effects of N-alpha-methyl-histamine on human H(2) receptors expressed in CHO cells. Gut 2002; 50:786-9. [PMID: 12010879 PMCID: PMC1773239 DOI: 10.1136/gut.50.6.786] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/08/2022]
Abstract
BACKGROUND Production of N-alpha-methyl-histamine (NAMH), a histamine H(3) receptor (H3R) agonist, is reportedly promoted in Helicobacter pylori infected human gastric mucosa. NAMH was suggested to act directly on histamine H(2) receptors (H2Rs) in animals to stimulate acid secretion and to be a H2R agonist. As H2Rs and H3Rs play different roles in gastric acid secretion, it is very important to verify that NAMH is a H2R agonist. AIMS To determine whether NAMH is a H2R agonist, as well as a H3R agonist. METHODS We used a Chinese hamster ovary (CHO) cell line expressing human H2Rs (CHO-H2R) and control CHO cells. Expression of human H2Rs was confirmed by tiotidine binding. cAMP production in CHO-H2R and control cells in response to histamine or NAMH was measured. cAMP production in response to 10(-7) M NAMH was also measured in the presence or absence of the H2R antagonist famotidine and the H3R antagonist thioperamide. RESULTS NAMH dose dependently stimulated cAMP productions in CHO-H2R cells. This production was inhibited by famotidine but not by thioperamide. Control CHO cells were unresponsive to either histamine or NAMH. In addition, the effect of NAMH, in terms of cAMP production in CHO-H2R cells, was more potent than that of histamine-that is, with a lower EC(50) concentration and higher maximal cAMP production. Both NAMH and histamine, but not R-alpha-methyl-histamine, effectively inhibited [(3)H] tiotidine binding to CHO-H2R cells. CONCLUSIONS NAMH, which is produced in the gastric mucosa by H pylori, is a potent H2R agonist as well as a H3R agonist.
Collapse
|
213
|
Van Eldik R, Asano T, Le Noble WJ. Activation and reaction volumes in solution. 2 [Erratum to document cited in CA110(24):219738v]. Chem Rev 2002. [DOI: 10.1021/cr00098a015] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
|
214
|
Balta Calleja FJ, Santa Cruz C, Sawatari C, Asano T. New aspects of the microstructure of polyethylene-isotactic polypropylene gel blends as revealed by microhardness: influence of composition. Macromolecules 2002. [DOI: 10.1021/ma00228a008] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
|
215
|
|
216
|
|
217
|
Le Noble WJ, Guggisberg H, Asano T, Cho L, Grob CA. Kinetics of reactions in solutions under pressure. XXXVII. Pressure effects in solvolysis and solvolytic fragmentation. A correlation of activation volume with concertedness. J Am Chem Soc 2002. [DOI: 10.1021/ja00420a009] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
|
218
|
Le Noble WJ, Asano T. Kinetics of reactions in solutions under pressure. XXXI. Ionization constants and volumes of highly hindered pyridines in methanol. J Org Chem 2002. [DOI: 10.1021/jo00896a044] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
|
219
|
Le Noble WJ, Asano T. Kinetics of reactions in solutions under pressure. XXX. Special effect of pressure on highly hindered reactions as a possible manifestation of the Hammond postulate. J Am Chem Soc 2002. [DOI: 10.1021/ja00840a027] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
|
220
|
Fukushima Y, Saitoh T, Anai M, Tsukuda K, Onishi Y, Sakoda H, Inukai K, Ogihara T, Funaki M, Ono H, Fujishiro M, Ishikawa T, Nagai R, Omata M, Asano T. G649, an allelic variant of the human H2 receptor with low basal activity, is resistant to upregulation upon antagonist exposure. THE PHARMACOGENOMICS JOURNAL 2002; 1:78-83. [PMID: 11913732 DOI: 10.1038/sj.tpj.6500011] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Orange et al reported an allelic variant of the human histamine H2 receptor, in which adenine 649 was replaced with guanine, to be more frequent in the schizophrenic population than controls in British Caucasians. The A649 to G change causes an Asn to Asp transition at amino acid position 217 in the third intracellular region, which is postulated to be important for receptor function. Herein, we analyzed the functional significance of this variant using wild-type and variant receptors expressed in Chinese hamster ovary cells. The variant receptor was associated with markedly lower basal cAMP productions than the wild-type receptor. Histamine-dependent cAMP productions via the variant receptor were lower as well. Treatment of cells expressing variant receptors with 10(-5) M ranitidine for 24 h resulted in a reduced degree of receptor upregulation as compared with the wild-type receptor. Thus, this is the first report of an allelic variant of the human H2 receptor which confers altered receptor function. To analyze gastric acid secretion in individuals with this variant, we examined 100 Japanese control subjects. However, neither heterozygotes nor homozygotes were found, suggesting that this variant, if present, is uncommon in the Japanese population.
Collapse
|
221
|
Fukushima Y, Otsuka H, Ishikawa M, Asano T, Anai M, Katsube T, Ogawa K, Kajiwara T, Ohkawa S, Ishikawa T, Omata M, Saitoh T. Potent and long-lasting action of lafutidine on the human histamine H(2) receptor. Digestion 2002; 64:155-60. [PMID: 11786663 DOI: 10.1159/000048856] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
BACKGROUND/AIM Based on animal models, lafutidine, a novel histamine H(2) receptor (H(2)R) antagonist, is reported to show potent and long-lasting antagonisms of histamine H(2)R-mediated effects. However, no reports have been published concerning its direct interaction with the human H(2)R. This study aims at characterizing its interaction with human H(2)R. METHODS Chinese hamster ovary cell lines stably expressing human H(2)Rs were obtained. The dose-dependent effects of lafutidine and famotidine on [(3)H]tiotidine binding and histamine-stimulated cAMP production were analyzed. The effects of preincubation with 2.78 x 10(-7) M of lafutidine or famotidine for 30 min on histamine-dependent cAMP production and [(3)H]tiotidine binding were also examined after 0, 1, 2, 4, and 12 h. This concentration is below the C(max) of lafutidine (10 mg p.o.) and above the C(max) of famotidine (20 mg p.o.). RESULTS Lafutidine inhibited [(3)H]tiotidine binding and histamine-stimulated cAMP production as or more potently than famotidine. At higher concentrations lafutidine was more potent than famotidine. In addition, preincubation with 2.78 x 10(-7) M lafutidine, but not with 10(-5) M famotidine, had marked inhibitory effects which persisted as long as after extensive washing. CONCLUSION Lafutidine shows a potent and long-lasting antagonism on the human H(2)R.
Collapse
|
222
|
Shibuya M, Asano T, Sasaki Y. Effect of Fasudil HCl, a protein kinase inhibitor, on cerebral vasospasm. ACTA NEUROCHIRURGICA. SUPPLEMENT 2002; 77:201-4. [PMID: 11563286 DOI: 10.1007/978-3-7091-6232-3_42] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
|
223
|
Hosono M, Machida K, Matsui T, Honda N, Takahashi T, Dei S, Kashimada A, Shimizu Y, Osada H, Ohmichi M, Asano T. Non-invasive quantitative monitoring of cerebral blood flow in aneurysmal subarachnoid haemorrhage with 99mTc-ECD. Nucl Med Commun 2002; 23:5-11. [PMID: 11748432 DOI: 10.1097/00006231-200201000-00003] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
The purpose of this prospective study was to detect symptomatic cerebral vasospasm in aneurysmal subarachnoid haemorrhage (SAH) by a non-invasive mean cerebral blood flow (mCBF) quantification using 99mTc-ethyl cysteinate dimer. Measurement of mCBF without blood sampling and single photon emission tomography (SPECT) were performed at 1 and 7 days after surgery in 35 consecutive SAH patients, of whom 16 were examined at day 30 as well. A decrease in mCBF of more than 10% on day 7 versus day 1 was considered to indicate vasospasm. On visual interpretation of SPECT, a perfusion decrease which appeared newly on day 7 was considered to indicate vasospasm. In total, nine of 35 patients had cerebral vasospasm confirmed by computed tomography (CT) and/or angiography. The mCBF measurement showed a 77.8% (7/9) sensitivity, a 88.5% (23/26) specificity, a 70.0% (7/10) positive predictive value, and a 92.0% (23/25) negative predictive value. SPECT yielded a 33.3% (3/9) sensitivity, a 73.1% (19/26) specificity, a 30.0% (3/10) positive predictive value, and a 76.0% (19/25) negative predictive value. On SPECT, decreased perfusion was observed in most of the patients at clipping sites, which might represent post-operative transient abnormal perfusion and should not be read as vasospasm. In conclusion, this mCBF measurement is more accurate than visual interpretation of SPECT for detecting vasospasm.
Collapse
|
224
|
Ichikawa T, Asano T, Wada T, Ohta M. Dynamics of Fission Modes Studied with the 3-dimensional Langevin Equation. ACTA ACUST UNITED AC 2002. [DOI: 10.14494/jnrs2000.3.67] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
|
225
|
Abstract
BACKGROUND Colorectal cancer (CRC) is a major cause of morbidity and mortality in industrialized countries. Experimental evidence has supported the hypothesis that dietary fibre may be protective for the development of CRC, although epidemiologic data have been inconclusive. OBJECTIVES We have conducted a systematic review and meta-analysis to assess the effect of dietary fibre on the incidence or recurrence of colorectal adenomas, the incidence of CRC, and the development of adverse events. SEARCH STRATEGY We identified randomized controlled trials from Medline, Embase, and the Cochrane Controlled Trials Register up to Oct 2001 SELECTION CRITERIA Randomized or quasi-randomized controlled trials were assessed. The population included all subjects that had adenomatous polyps but no previous history of colorectal cancer (CRC), a documented "clean colon" at baseline and repeated visualization of the colon/rectum after at least two years of follow-up. Dietary fibre was the intervention. The primary outcomes were the number of subjects with: a) at least one adenoma, b) more than one adenoma, c) at least one adenoma greater than or equal to 1 cm or d) a new diagnosis of CRC. The secondary outcome was the number of adverse events. DATA COLLECTION AND ANALYSIS Two reviewers independently extracted data, assessed trial quality and resolved discrepancies by consensus. The outcomes were reported as relative risks (RR) and risk difference (RD) with 95% confidence intervals (CI). If statistical significance was reached, the number need to treat (NNTT) or harm (NNTH) was reported. The study data were combined with the fixed effects model if it was clinically, methodologically, and statistically reasonable. MAIN RESULTS Five studies with 4349 subjects met the inclusion criteria. The interventions were wheat bran fibre, ispaghula husk, or a comprehensive dietary intervention with high fibre whole food sources alone or in combination. When the data were combined there was no difference between the intervention and control groups for the number of subjects with at least one adenoma [RR 1.04 (95% CI 0.95,1.13); RD 0.01 (95% CI 0.02,0.04)]. As well, the combined results for the number of subjects with more than one adenoma [RR 1.02 (95% CI 0.89,1.17), RD 0.00 (-0.02,0.03)] or at least one adenoma 1 cm or greater [RR 0.94 (95% CI 0.77,1.15), RD -0.01 (-0.02,0.01)] were not statistically significant. Other primary and secondary outcomes and subanalyses by type of fibre intervention were not statistically or clinically significant. REVIEWER'S CONCLUSIONS There is currently no evidence from RCTs to suggest that increased dietary fibre intake will reduce the incidence or recurrence of adenomatous polyps within a two to four year period.
Collapse
|
226
|
Asano T, Shinohara H, Morishita R, Ueda H, Kawamura N, Katoh-Semba R, Kishikawa M, Kato K. Selective localization of G protein gamma5 subunit in the subventricular zone of the lateral ventricle and rostral migratory stream of the adult rat brain. J Neurochem 2001; 79:1129-35. [PMID: 11752054 DOI: 10.1046/j.1471-4159.2001.00662.x] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
G proteins play important roles in transmembrane signal transduction, and various isoforms of each subunit, alpha, beta and gamma, are highly expressed in the brain. The Ggamma5 subunit is a minor isoform in the adult brain, but we have previously shown it to be highly expressed in the proliferative region of the ventricular zone in the rat embryonic brain. We show here that Ggamma5 is also selectively localized in a proliferative region in the adult rat brain, including the subventricular zone of the lateral ventricle and rostral migratory stream. The Galphai2 subunit colocalized with Ggamma5 in these regions, the two subunits being present in neuronal precursors and ependymal cells but not in proliferating astrocytes. In addition, intense staining of Ggamma5 was seen in axons of the olfactory neurons, which are known to regenerate. These results suggest specific roles for Ggamma5 in precursor cells during neurogenesis so that this isoform might be a useful biological marker.
Collapse
|
227
|
Utsunomiya T, Satoh S, Ikegaki I, Toshima Y, Asano T, Shimokawa H. Antianginal effects of hydroxyfasudil, a Rho-kinase inhibitor, in a canine model of effort angina. Br J Pharmacol 2001; 134:1724-30. [PMID: 11739249 PMCID: PMC1572897 DOI: 10.1038/sj.bjp.0704410] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Abstract
1. The effects of Rho-kinase inhibitor, fasudil, and of a more specific Rho-kinase inhibitor, hydroxyfasudil, on pacing-induced myocardial ischaemia were determined in anaesthetized open-chest dogs. 2. The dogs were subjected to left anterior descending coronary artery (LAD) stenosis producing a sufficient ischaemia as measured by ST-segment depression on electrocardiograms only when the hearts were paced 60 beats min(-1) above the baseline. After a recovery (nonpacing) period, drugs or saline were infused intravenously over 30 min. The animals were again subjected to 5 min of pacing 25 min after the initiation of the treatment. 3. Hydroxyfasudil (0.1 and 0.3 mg kg(-1)) and fasudil (0.3 mg kg(-1)) suppressed the ST-segment depression. Hydroxyfasudil and fasudil also increased the regional blood flow of the LAD perfused endomyocardium region in the canine model of effort angina. 4. To determine the flow profile for hydroxyfasudil in dogs, blood flow in three vascular beds was measured. Hydroxyfasudil (0.3 mg kg(-1) for 30 min) significantly increased coronary blood flow and vertebral blood flow, without significantly changing the femoral blood flow. 5. Hydroxyfasudil had no inotropic or chronotropic effect on the isolated hearts of guinea-pigs. Hydroxyfasudil (2 mg kg(-1) for 20 min) did not affect the PR or QTc interval in anaesthetized dogs. 6. Inhibition of Rho-kinase appears to protect myocardium subjected to pacing-induced ischaemia through the increase in the regional myocardial blood flow. Hydroxyfasudil may be categorized as a novel type of anti-anginal drug, without any inotropic or chronotropic effects.
Collapse
|
228
|
Ueda H, Morishita R, Itoh H, Narumiya S, Mikoshiba K, Kato K, Asano T. Galpha11 induces caspase-mediated proteolytic activation of Rho-associated kinase, ROCK-I, in HeLa cells. J Biol Chem 2001; 276:42527-33. [PMID: 11546796 DOI: 10.1074/jbc.m102529200] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Expression of the constitutively active mutant of Galpha(11) (Galpha(11)QL) induces the formation of vinculin-containing focal adhesion-like structures in HeLa cells. This was found to be inhibited by Y-27632, a specific inhibitor of Rho-associated kinases (ROCK), but not by co-expression with a dominant negative mutant of RhoA, suggesting Rho-independent activation of ROCK by Galpha(11)QL. Investigation of trypan blue exclusion and immunocytochemistry with an antibody against cleaved caspase revealed the cellular phenotype of Galpha(11)QL-expressing cells to be identical to that displayed by cells undergoing apoptosis, and the caspase inhibitor zVAD-fmk blocked all morphological changes induced by Galpha(11)QL. Transfection of Galpha(11)QL induced cleavage of ROCK-I, and this proteolysis was also prevented by zVAD-fmk. ROCK-I C-terminally truncated at its authentic caspase sites also induced the formation of vinculin-containing focal adhesion-like structures. In addition, cleavage of ROCK-I was observed when cells overexpressing m1 muscarinic acetylcholine receptors were stimulated with carbachol. These results suggest that Galpha(11) induces proteolytic activation of ROCK-I by caspase and thereby regulates the actin cytoskeleton during apoptosis.
Collapse
|
229
|
Kobayashi S, Asano T, Kenmochi T, Saigo K, Matsutani S, Maruyama H, Saisho H, Okuda K, Ochiai T. Arterio-portal shunt in liver rescued by hepatectomy after arterial embolization. HEPATO-GASTROENTEROLOGY 2001; 48:1730-2. [PMID: 11813610] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 04/17/2023]
Abstract
Arterio-portal shunts are generally treated with transcatheter arterial embolization, as a therapeutic measure for bleeding of esophageal varices. However, transcatheter arterial embolization is frequently associated with reestablishment of arterio-portal shunts. We now report our experience with partial hepatectomy to remove the arterio-portal shunt associated with esophageal varices, which recurred after transcatheter arterial embolization. The patient was a 60-year-old female, who had massive hematemesis caused by rupture of esophageal varices. Doppler sonography and arteriography demonstrated an arterio-portal shunt in the right anterior superior segment of the liver. Temporary hemostasis was achieved with transcatheter arterial embolization, however, hemorrhage recurred one month later. The second transcatheter arterial embolization failed to manage the shunt and varices. The patient developed hepatic coma. After recovery from coma, she was referred to our hospital. We carried out partial hepatectomy, which provided remarkable hemodynamic improvement; the portal vein flow changed from hepatofugal to hepatopetal. Esophageal varices and hepatic coma have totally disappeared. This patient has had no complaint and has remained free of esophageal varices, for 3 years postoperatively. She is having a normal life. The partial hepatectomy to remove the arterio-portal shunt induced complete resolution of the arterio-portal shunt, as well as dramatic improvement in portal flow and hepatic coma. Our experience in the present case suggests that partial hepatectomy should be considered as a radical therapy for arterio-portal shunt, without insistence on transcatheter arterial embolization.
Collapse
|
230
|
Kubo M, Matsuda H, Asano T. [Historical investigation on herbal and medical literatures of processing and effect of Rehmanniae Radix]. YAKUSHIGAKU ZASSHI 2001; 31:23-8. [PMID: 11619111] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/21/2023]
Abstract
The radix of Rehmannia glutinosa has been applied to medicinal use since ancient times, and has been called Kiou in the Han dynasty and has been classified by prepared methods, with each preparation given a different name. There were Syoujiou, Kanjiou and Zyukujiou etc. The first was introduced in the Sinnou-honzoukyou and the first and second had been used to prepare some prescriptions contained in the Kinki-youryaku and so on. The third began to appear on the medical and herbal literatures from the Tang period to the early Song. The Rehmanniae Radix has been used as the main material of Hokyoyouketu prescriptions, and by the use of Zyukujiou, their efficacy was regarded to be particularly stronger than the others. The preparation of Hatimigan recorded in the Kinki-youryaku had been used in Kanjiou but was later replaced with Zyukujiou. We should rethink about the quality and process of Chinese herbs on the pharmacy of Kampo medicine.
Collapse
|
231
|
Yano S, Houkin K, Abe S, Saitoh H, Kuroda S, Asano T, Ushikoshi S, Iwasaki Y. [Angioplasty with stenting for intracranial vertebral and basilar artery stenosis: three technical case reports and literature review]. NO SHINKEI GEKA. NEUROLOGICAL SURGERY 2001; 29:1081-90. [PMID: 11758316] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/23/2023]
Abstract
Patients with intracranial vertebral artery (VA) or basilar artery (BA) stenosis have been mainly treated with medication. However, it has been reported that about 10% of patients experience restroke in the VBA territory, with a high rate of morbidity and mortality. Percutaneous transluminal angioplasty (PTA) is regarded as one of the treatments although it carries the risk of restenosis, recoil or dissection. Stent placement is, therefore, considered to be a further option for the treatment of intracranial artery stenosis since it can prevent the restenosis. We report three medical refractory cases of intracranial VA (2 cases) or BA stenosis (1 case) treated with stenting, none of which had complications and their symptoms disappeared or diminished. Angioplasty with the use of a stent device is regarded as a useful treatment for intracranial artery stenosis, but its risk and long-term result need to be investigated further.
Collapse
|
232
|
Maeda T, O-Wang J, Matsubara H, Asano T, Ochiai T, Sakiyama S, Tagawa M. A minimum c-erbB-2 promoter-mediated expression of herpes simplex virus thymidine kinase gene confers selective cytotoxicity of human breast cancer cells to ganciclovir. Cancer Gene Ther 2001; 8:890-6. [PMID: 11773979 DOI: 10.1038/sj.cgt.7700389] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2001] [Indexed: 12/12/2022]
Abstract
The c-erbB-2 gene is frequently overexpressed in human breast cancers as a result of gene amplification and/or elevated transcription. We therefore examined a possible usage of promoter regions of the c-erbB-2 gene to express a suicide gene preferentially in breast cancer cells. Previous studies did not reveal the minimal promoter region that enabled transcriptional activation specific to breast cancer cells. The present reporter gene assays using deletion mutants of the c-erbB-2 promoter region demonstrated that the 251-bp (-213/+38 from the transcriptional start site), but not the 125-bp, fragment (-87/+38) could direct transcription of the linked luciferase gene better than the SV40 immediate early promoter in breast cancer cells. In contrast, the 251-bp fragment-mediated promoter activity in nonbreast cancer cells and in normal fibroblasts was lower than the activity by the SV40 promoter. The 126-bp fragment (-213/-87) thereby contains a cis-acting element(s), which is responsible for the preferential transcriptional activity in breast cancer cells. An electrophoretic mobility shift assay suggested that a possible modification of a transcriptional factor was involved in the tumor specificity. Transfection with the plasmid DNA containing the herpes simplex virus thymidine kinase gene linked with the 251-bp promoter (p256-TK) resulted in increased sensitivity to ganciclovir in breast cancer, but not in nonbreast cancer cells. Administration of ganciclovir into nude mice bearing human breast tumors that were transfected with the p256-TK DNA suppressed subsequent growth of the transplanted tumors. These results suggest that delivery of a suicide gene linked with the 251-bp c-erbB-2 promoter can be a feasible therapeutic strategy specific to breast cancer.
Collapse
|
233
|
Hino T, Asano T, Tojyo T, Kijima S, Tomiya S, Miyajima T, Uchida S, Ikeda M. Estimation of Device Properties in AlGaInN-Based Laser Diodes by Time-Resolved Photoluminescence. ACTA ACUST UNITED AC 2001. [DOI: 10.1002/1521-396x(200111)188:1<101::aid-pssa101>3.0.co;2-o] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
|
234
|
Ikegami S, Yoshimura I, Tsuji A, Seta K, Kimura F, Odajima K, Asano T, Hayakawa M. [Immunohistochemical study of p53 and Ki-67 overexpression in grade 3 superficial bladder tumor in relationship to tumor recurrence and prognosis]. Nihon Hinyokika Gakkai Zasshi 2001; 92:656-65. [PMID: 11766364 DOI: 10.5980/jpnjurol1989.92.656] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
PURPOSE The major drawback of the current treatment for superficial bladder tumor is the high rate of recurrence. Especially, the tumor with grade 3 component has a tendency to recur and progress in stage. However, we have difficulty in predicting tumor recurrence and stage progression accurately by conventional clinicopathological factors. We evaluated the efficacy of p53 and Ki-67 overexpression as a predictor of recurrence or prognosis in patients with superficial bladder tumor of grade 3. MATERIALS AND METHODS Samples were obtained from 41 patients with superficial transitional cell carcinoma of the bladder of grade 3 who were treated by transurethral resection (TUR). The immunohistochemical study was performed using the antibodies against the p53 protein and Ki-67 antigen on formalin-fixed, paraffinembedded tissue specimens from initial tumors. We evaluated the correlation between these results and several clinicopathological factors. RESULTS The p53 index and the Ki-67 index in pTa, pT1a and pT1b tumors were 26.4 +/- 30.1%, 28.6 +/- 30.0%, and 34.6 +/- 32.6% (p53) and 20.5 +/- 22.5%, 20.0 +/- 29.3%, and 29.2 +/- 28.4% (Ki-67). There was no significant difference between the each index and tumor stage. Eighteen cases (43.9%) had intravesical recurrence. The p53 index of the initial tumor from the tumor free cases (n = 23), recurrent cases without stage progression (n = 12), and stage progression cases (n = 6) were 19.7 +/- 28.2%, 42.0 +/- 28.7%, and 42.5 +/- 32.0%. Between the recurrence-free cases and the recurrent cases without progression, the p53 index of the initial tumor had statistical significance (p < 0.05). The Ki-67 index was shown to be the same pattern as the p53 index, but there was not statistical significance. Four of patients with stage progression had tumor progression within six months. Three of the patients with tumors with stage progression died of the cancer. In multivariate analysis, tumor multiplicity (p = 0.01), BCG intravesical instillation (p = 0.04), p53 index (p = 0.01) and Ki-67 index (p = 0.02) were the positive risk factors for tumor recurrence, but only the p53 index was the positive risk factor for prognosis fo the patients (p = 0.03). CONCLUSION These results suggest that the immunohistochemical study of p53 overexpression is a useful predictor for tumor recurrence and prognosis in patients with superficial bladder tumor with grade 3.
Collapse
|
235
|
Onishi-Haraikawa Y, Funaki M, Gotoh N, Shibuya M, Inukai K, Katagiri H, Fukushima Y, Anai M, Ogihara T, Sakoda H, Ono H, Kikuchi M, Oka Y, Asano T. Unique phosphorylation mechanism of Gab1 using PI 3-kinase as an adaptor protein. Biochem Biophys Res Commun 2001; 288:476-82. [PMID: 11606067 DOI: 10.1006/bbrc.2001.5791] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Grb2-associated binder-1 (Gab1) undergoes tyrosine phosphorylation in response to stimulation by growth factors and hormones including insulin, epidermal growth factor (EGF), nerve growth factor (NGF), and hepatocyte growth factor (HGF). However, the HGF receptor is the only one known to associate directly with Gab1. Herein, we explore the mechanism of Gab1 phosphorylation by other receptor protein-tyrosine kinases unable to bind to Gab1 directly. The Src homology 2 (SH2) domain of the phosphatidylinositol 3-kinase (PI3K) regulatory subunit binds Gab1 in a phosphorylation-independent manner. Moreover, the regulatory subunit of PI3K can mediate the association of Gab1 and receptor protein-tyrosine kinases including the insulin, EGF, and NGF receptors, all of which phosphorylate Gab1. Thus, it appears that the PI3K regulatory subunit acts as an adaptor protein via a phosphotyrosyl-independent SH2 interaction, allowing Gab1 to serve as a substrate for several tyrosine kinases. This is a new role for the PI3K regulatory subunit.
Collapse
|
236
|
Ikegaki I, Hattori T, Yamaguchi T, Sasaki Y, Satoh SI, Asano T, Shimokawa H. Involvement of Rho-kinase in vascular remodeling caused by long-term inhibition of nitric oxide synthesis in rats. Eur J Pharmacol 2001; 427:69-75. [PMID: 11553365 DOI: 10.1016/s0014-2999(01)01181-5] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Long-term inhibition of nitric oxide (NO) synthesis with N(omega)-nitro-L-arginine methyl ester (L-NAME) induces coronary vascular remodeling in rats. To determine the pathogenic mechanism involved in vascular remodeling, we examined the effects of fasudil, a Rho-kinase inhibitor, on vascular lesion formation. In rats treated with L-NAME at 10 mg/kg/day, vascular remodeling was evident in both large and small coronary arteries at the fourth week. Fasudil (3 mg/kg, p.o., twice daily) markedly prevented the development of vascular remodeling in small coronary arteries. Coronary flow was measured in Langendorff perfused isolated heart preparations. Long-term treatment with L-NAME caused a significant decrease in coronary flow, which was significantly inhibited by fasudil. Fasudil suppressed the structural and functional changes in coronary arteries by chronic blockade of NO synthesis. Thus, the Rho-kinase pathway may be substantially involved in the pathogenesis of vascular remodeling in this rat model.
Collapse
|
237
|
Miyajima A, Ito K, Asano T, Seta K, Ueda A, Hayakawa M. Does cyclooxygenase-2 inhibitor prevent renal tissue damage in unilateral ureteral obstruction? J Urol 2001; 166:1124-9. [PMID: 11490310] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/21/2023]
Abstract
PURPOSE We determined whether the cyclooxygenase-2 inhibitor etodolac affects renal tubular damage and interstitial fibrosis in unilateral ureteral obstruction. MATERIALS AND METHODS Etodolac (10 mg./kg.) was administered to rats 1 day before unilateral ureteral obstruction and every day thereafter. Kidneys were harvested at day 14 after unilateral ureteral obstruction. Tissue transforming growth factor-beta and prostaglandin E2 were measured by bioassay using mink lung epithelial cells and enzyme linked immunosorbent-sandwich assay. Renal tubular proliferation and apoptosis were detected by immunostaining with proliferating cellular nuclear antigen and by terminal deoxynucleotidyl transferase mediated deoxyuridine triphosphate nick end labeling, respectively. Cyclooxygenase-2 expression was detected by immunohistochemistry. Fibrosis was assessed by measuring collagen deposition in trichrome stained slides. RESULTS Bioassay showed that in the control group obstructed kidneys contained significantly higher mean transforming growth factor-beta1 than unobstructed kidneys (79.1 +/- 8.3 versus 33.6 +/- 4.2 ng./gm. tissue) and etodolac significantly decrease the mean value in obstructed kidneys (46.2 +/- 10.0 ng./gm. tissue). Assay demonstrated that obstructed control kidneys had significantly more mean tubular apoptosis than their unobstructed counterparts (26.6 +/- 5.4 versus 2.2 +/- 1.4 nuclei per high power field) and etodolac significantly decreased mean renal tubular apoptosis in the obstructed kidneys (16.2 +/- 1.9 nuclei per high power field). In addition, immunostaining with proliferating cellular nuclear antigen showed that obstructed kidneys in the control group had significantly more mean renal tubular proliferation than unobstructed kidneys (9.8 +/- 3.4 versus 3.9 +/- 0.1 per high power field) and etodolac significantly increased mean proliferating renal tubule in the obstructed kidneys (24.9 +/- 4.3 per high power field). Control obstructed kidneys had significantly more fibrosis and prostaglandin E2 production, which were also significantly blunted by etodolac. CONCLUSIONS The cyclooxygenase-2 inhibitor etodolac significantly reduces tissue transforming growth factor-beta, resulting in decreased tubular damage and interstitial fibrosis. This finding suggests that etodolac is a promising agent for preventing renal tissue damage in unilateral ureteral obstruction.
Collapse
|
238
|
Sato S, Ikegaki I, Asano T, Shimokawa H. Antiischemic properties of fasudil in experimental models of vasospastic angina. JAPANESE JOURNAL OF PHARMACOLOGY 2001; 87:34-40. [PMID: 11676196 DOI: 10.1254/jjp.87.34] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
We studied the antiischemic properties of fasudil, a Rho-kinase inhibitor, in conscious rabbits with coronary vasospasm induced by vasopressin and endothelin. Pretreatment with fasudil (0.3 and 3 mg/kg) attenuated the maximum elevation of the T-wave elicited by endothelin. Pretreatment with fasudil inhibited the T-wave elevation elicited by vasopressin. Fasudil and hydroxy fasudil, an active metabolite of fasudil, relaxed the endothelin-, U-46619-, 5-hydroxytryptamine- or histamine-induced contraction in swine coronary arterial strips. Fasudil and hydroxy fasudil significantly prevented the reduction in coronary flow by vasopressin in the Langendorff perfused rat heart. Fasudil was effective in protecting the heart against vasopressin and endothelin-induced myocardial ischemic change in conscious rabbits, and this beneficial effect can be attributed to its action of ameliorating the severe contraction of arteries. The inhibition of Rho-kinase may have implications for the development of novel therapeutic strategies for vasospastic angina in patients.
Collapse
|
239
|
Ohkubo K, Yamano A, Nagashima M, Mori Y, Anzai K, Akehi Y, Nomiyama R, Asano T, Urae A, Ono J. Mitochondrial gene mutations in the tRNA(Leu(UUR)) region and diabetes: prevalence and clinical phenotypes in Japan. Clin Chem 2001; 47:1641-8. [PMID: 11514398] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/21/2023]
Abstract
BACKGROUND Mitochondrial gene mutations play a role in the development of diabetes mellitus. We have assessed the frequency of the A3243G and other mitochondrial mutations in Japan and in the relationship to clinical features of diabetes. METHODS DNA was obtained from peripheral leukocytes of 240 patients with diabetes mellitus (39 with type 1; 188 with type 2; 13 with gestational diabetes) and 125 control subjects. We used PCR-restriction fragment length polymorphism analysis (ApaI) for A3243G and PCR-single-strand conformation polymorphism analysis to determine the mutations in the mitochondrial gene including nucleotide position 3243. RESULTS The A3243G mutation was found in seven patients, and an inverse relationship was observed between the degree of heteroplasmy and the age at onset of diabetes. A3156G, G3357A, C3375A, and T3394C were detected in addition. Those who shared the same mutation showed similar clinical characteristics, thus representing a putative clinical subtype. The patients with A3156G had a sudden onset of hyperglycemia and showed a rapid progression to an insulin-dependent state with positive anti-glutamic acid decarboxylase antibody. Those with T3394C showed a mild defect in glucose-stimulated insulin secretion, and hyperglycemia appeared after adding such factors as aging or obesity. CONCLUSIONS The identification of mitochondrial gene mutations allows preclinical diagnosis of diabetes and prediction of the age at onset by evaluating the degree of heteroplasmy in cases with A3243G. Mutation detection may also be important for patient management and identification of affected family members.
Collapse
|
240
|
Hanyu H, Asano T, Kogure D, Abe S, Iwamoto T, Takasaki M. [Diagnosis of Alzheimer's disease using brain SPECT with three-dimensional stereotactic surface projections]. Rinsho Shinkeigaku 2001; 41:582-7. [PMID: 11968741] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/24/2023]
Abstract
We compared the diagnostic usefulness of three-dimensional stereotactic surface projection (3D-SSP) with that of standard transaxial images in brain SPECT in patients with Alzheimer's disease (AD). The subjects consisted of 69 patients with AD and 60 patients with non-AD, including vascular dementia, Parkinson's disease with dementia, frontotemporal dementia, other dementing diseases and neuropsychiatric diseases. Standard transaxial section and 3D-SSP SPECT images with N-isopropyl-p-[123I] iodoamphetamine were blindly interpreted by three examiners and were classified into the following three patterns: typical AD, atypical AD, and not indicative AD patterns. The 3D-SSP images demonstrated reductions of cerebral blood flow in the parieto-temporal association cortex and posterior cingulate gyrus more clearly and easily than the standard transaxial images. The diagnostic sensitivity and specificity were 93% and 85% with 3D-SSP and 83% and 82% with standard transaxial section respectively. 3D-SSP was especially useful for early or atypical AD which showed no characteristic perfusion abnormalities on standard transaxial images. These results suggest that SPECT with 3D-SSP provides an sensitive as well as accurate tool for the diagnosis of AD.
Collapse
|
241
|
Iida KT, Shimano H, Kawakami Y, Sone H, Toyoshima H, Suzuki S, Asano T, Okuda Y, Yamada N. Insulin up-regulates tumor necrosis factor-alpha production in macrophages through an extracellular-regulated kinase-dependent pathway. J Biol Chem 2001; 276:32531-7. [PMID: 11443108 DOI: 10.1074/jbc.m009894200] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Hyperinsulinemia has recently been reported as a risk factor for atherosclerotic diseases such as coronary heart disease; however, the effect of insulin on the development of atherosclerosis is not well understood. Here we have investigated the direct effect of insulin on macrophages, which are known to be important in the atherosclerotic process. We treated THP-1 macrophages with insulin (10(-7) m) and examined the gene expression using nucleic acid array systems. The results of array analysis showed that insulin stimulated gene expression of tumor necrosis factor-alpha (TNF-alpha) the most among all genes in the analysis. In addition, insulin administration to macrophages enhanced both mRNA expression and protein secretion of TNF-alpha in a dose-dependent manner. To determine the signaling pathway involved in this TNF-alpha response to insulin, we pretreated the cells with three distinct protein kinase inhibitors: wortmannin, PD98059, and SB203580. Only PD98059, which inhibits extracellular signal-regulated kinases, suppressed insulin-induced production of TNF-alpha mRNA and protein in THP-1 macrophages. These observations indicate that insulin stimulates TNF-alpha production in macrophages by regulating the expression of TNF-alpha mRNA and that the extracellular signal-regulated kinase signaling pathway may have a critical role in stimulating the production of TNF-alpha in response to insulin in macrophages.
Collapse
|
242
|
Satoh S, Utsunomiya T, Tsurui K, Kobayashi T, Ikegaki I, Sasaki Y, Asano T. Pharmacological profile of hydroxy fasudil as a selective rho kinase inhibitor on ischemic brain damage. Life Sci 2001; 69:1441-53. [PMID: 11531167 DOI: 10.1016/s0024-3205(01)01229-2] [Citation(s) in RCA: 135] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
The neuroprotective property and the effects on hemodynamics of hydroxy fasudil, an active metabolite of an antispastic drug, fasudil, were examined. In rats, hydroxy fasudil was found following intravenous infusion or intraperitoneal administration of fasudil, and the maximum plasma concentration of hydroxy fasudil was approximately 25 or 40% of the parent drug, respectively. The i.v. administration of hydroxy fasudil produced significant increases in regional cerebral blood flow in dogs. Hydroxy fasudil relaxed the KCl, PGF2alpha or U-46619-induced contraction in canine basilar or middle cerebral arterial strips, concentration-dependently. The neuroprotective property of hydroxy fasudil was examined on delayed neuronal death in gerbils. Hydroxy fasudil (3 mg/kg) significantly protected against the ischemia-induced neuronal loss. To further clarify the effect on neurological impairments, hydroxy fasudil was tested in a rat model of microembolization stroke. Intravenous administration of hydroxy fasudil improved neurological functions, significantly reduced the size of the infarct area and prevented the accumulation of neutrophils. The present findings suggest that hydroxy fasudil has an efficacy to improve the hemodynamic function and to inhibit neutrophil-mediated damage, and contributes to the potency and long duration of the cytoprotective properties of fasudil on ischemic brain damage, and also suggest a critical role for rho kinase in the pathogenesis of cerebral ischemic injury, and the potential utility of rho kinase inhibitor as a therapeutic agent in stroke.
Collapse
|
243
|
Kinoshita M, Nukada T, Asano T, Mori Y, Akaike A, Satoh M, Kaneko S. Binding of G alpha(o) N terminus is responsible for the voltage-resistant inhibition of alpha(1A) (P/Q-type, Ca(v)2.1) Ca(2+) channels. J Biol Chem 2001; 276:28731-8. [PMID: 11395521 DOI: 10.1074/jbc.m104806200] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
G-protein-mediated inhibition of presynaptic voltage-dependent Ca(2+) channels is comprised of voltage-dependent and -resistant components. The former is caused by a direct interaction of Ca(2+) channel alpha(1) subunits with G beta gamma, whereas the latter has not been characterized well. Here, we show that the N terminus of G alpha(o) is critical for the interaction with the C terminus of the alpha(1A) channel subunit, and that the binding induces the voltage-resistant inhibition. An alpha(1A) C-terminal peptide, an antiserum raised against G alpha(o) N terminus, and a G alpha(o) N-terminal peptide all attenuated the voltage-resistant inhibition of alpha(1A) currents. Furthermore, the N terminus of G alpha(o) bound to the C terminus of alpha(1A) in vitro, which was prevented either by the alpha(1A) channel C-terminal or G alpha(o) N-terminal peptide. Although the C-terminal domain of the alpha(1B) channel showed similar ability in the binding with G alpha(o) N terminus, the above mentioned treatments were ineffective in the alpha(1B) channel current. These findings demonstrate that the voltage-resistant inhibition of the P/Q-type, alpha(1A) channel is caused by the interaction between the C-terminal domain of Ca(2+) channel alpha(1A) subunit and the N-terminal region of G alpha(o).
Collapse
|
244
|
Goda Y, Asano T, Shibuya M, Hino A, Toyoda M. [Detection of recombinant DNA from genetically modified papaya]. SHOKUHIN EISEIGAKU ZASSHI. JOURNAL OF THE FOOD HYGIENIC SOCIETY OF JAPAN 2001; 42:231-6. [PMID: 11817137 DOI: 10.3358/shokueishi.42.231] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
A method using polymerase chain reaction (PCR) was developed to detect the genetically modified (GM) papaya (55-1 line), of which the mandatory safety assessment has not been finished in Japan because of insufficient data. The papaya intrinsic papain gene was used as an internal control. The results of PCR amplification of the papain gene segment indicated that a commercial silica membrane type kit (QIAGEN DNeasy plant mini) was useful for extraction of DNA from papaya fruit, but not for extraction from canned papaya fruit. On the other hand, a commercial ion-exchange type kit (QIAGEN Genomic-tip) provided enough purified DNA for PCR from canned papaya fruit. Compared with the parental line and other commercial non-GM papayas, the DNA from GM papaya fruit provided specific amplification bands in PCR with five primer pairs (Nos. 2-6) including beta-glucuronidase and neomycin phosphotransferase II gene-specific ones. On the other hand, the primer pairs recognizing these genes showed false-positive results when we used DNAs from canned papaya. Therefore, we recommend that the primer pairs (Nos. 5 and 6) recognizing the sequences derived from two different species of organism should be used in order to detect specifically the GM papaya in canned fruits.
Collapse
|
245
|
Tominaga T, Sano M, Nishi T, Sasaki M, Yoshida K, Kimura M, Takashima S, Asano T, Yoshida M, Fujiwara J, Danno M. Postoperative chemoendocrine therapy for women with node-positive stage II breast cancer with combined cyclophosphamide, tamoxifen, and 1-hexylcarbamoyl-5-fluorouracil. THE EUROPEAN JOURNAL OF SURGERY = ACTA CHIRURGICA 2001; 167:598-604. [PMID: 11716446 DOI: 10.1080/110241501753171209] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/16/2022]
Abstract
OBJECTIVE To find out whether the addition of 1-hexylcarbamoyl-5-fluorouracil to a postoperative regimen of oral cyclophosphamide and tamoxifen improved the prognosis of carcinoma of the breast. DESIGN Randomised controlled clinical trial. SETTING 127 Institutions in Japan. SUBJECTS 785 Patients with stage II carcinoma (palpable axillary nodes) who had total mastectomy and axillary clearance. INTERVENTIONS The control group were given oral cyclophosphamide 50 mg/day and tamoxifen 20 mg/day for 2 years; the experimental group were given these drugs plus 1-hexylcarbamoyl-5-fluorouracil 300 mg/day for 2 years. RESULTS There was no survival advantage (and more toxicity) in the experimental group, except in a subgroup with 1-3 axillary nodes involved. CONCLUSION The advantage of triple chemotherapy in the subgroup must be substantiated by a new randomised trial confined to patients with 1-3 axillary nodes involved.
Collapse
|
246
|
Ono H, Katagiri H, Funaki M, Anai M, Inukai K, Fukushima Y, Sakoda H, Ogihara T, Onishi Y, Fujishiro M, Kikuchi M, Oka Y, Asano T. Regulation of phosphoinositide metabolism, Akt phosphorylation, and glucose transport by PTEN (phosphatase and tensin homolog deleted on chromosome 10) in 3T3-L1 adipocytes. Mol Endocrinol 2001; 15:1411-22. [PMID: 11463863 DOI: 10.1210/mend.15.8.0684] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023] Open
Abstract
To investigate the roles of PTEN (phosphatase and tensin homolog deleted on chromosome 10) in the regulation of 3-position phosphorylated phosphoinositide metabolism as well as insulin-induced Akt phosphorylation and glucose metabolism, wild-type PTEN and its phosphatase-dead mutant (C124S) with or without an N-terminal myristoylation tag were overexpressed in Sf-9 cells and 3T3-L1 adipocytes using baculovirus and adenovirus systems, respectively. When expressed in Sf-9 cells together with the p110alpha catalytic subunit of phosphoinositide 3-kinase, myristoylated PTEN markedly reduced the accumulations of both phosphatidylinositol 3,4-bisphosphate and phosphatidylinositol 3,4,5-trisphosphate induced by p110alpha. In contrast, overexpression of the C124S mutants apparently increased these accumulations. In 3T3-L1 adipocytes, insulin-induced accumulations of phosphatidylinositol 3,4-bisphosphate and phosphatidylinositol 3,4,5-trisphosphate were markedly suppressed by overexpression of wild-type PTEN with the N-terminal myristoylation tag, but not by that without the tag. On the contrary, the C124S mutants of PTEN enhanced insulin-induced accumulations of phosphatidylinositol 3,4-bisphosphate and phosphatidylinositol 3,4,5-trisphosphate. Interestingly, the phosphorylation level of Akt at Thr308 (Akt2 at Thr309), but not at Ser473 (Akt2 at Ser474), was revealed to correlate well with the accumulation of phosphatidylinositol 3,4,5-trisphosphate modified by overexpression of these PTEN proteins. Finally, insulin-induced increases in glucose transport activity were significantly inhibited by the overexpression of myristoylated wild-type PTEN, but were not enhanced by expression of the C124S mutant of PTEN. Therefore, in conclusion, 1) PTEN dephosphorylates both phosphatidylinositol 3,4-bisphosphate and phosphatidylinositol 3,4,5-trisphosphate in vivo, and the C124S mutants interrupt endogenous PTEN activity in a dominant-negative manner. 2) The membrane targeting process of PTEN may be important for exerting its function. 3) Phosphorylations of Thr309 and Ser474 of Akt2 are regulated differently, and the former is regulated very sensitively by the function of PTEN. 4) The phosphorylation level of Ser474, but not that of Thr309, in Akt2 correlates well with insulin-stimulated glucose transport activity in 3T3-L1 adipocytes. 5) The activity of endogenous PTEN may not play a major role in the regulation of glucose transport activity in 3T3-L1 adipocytes.
Collapse
|
247
|
Ogushi F, Tani K, Endo T, Tada H, Kawano T, Asano T, Huang L, Ohmoto Y, Muraguchi M, Moriguchi H, Sone S. Autoantibodies to IL-1 alpha in sera from rapidly progressive idiopathic pulmonary fibrosis. THE JOURNAL OF MEDICAL INVESTIGATION 2001; 48:181-9. [PMID: 11694958] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/22/2023]
Abstract
To clarify the clinical significance of autoantibodies to interleukin-1 alpha (IL-1 alpha autoantibodies) in rapidly progressive idiopathic pulmonary fibrosis (IPF), we measured the level of IL-1 alpha autoantibodies in serum of 11 patients on the first hospital day, when patients were admitted due to severe symptoms, and on the 21st hospital day. IL-1 alpha autoantibodies in serum were measured using radioimmunoassay, and the limitation of this assay for IL-1 alpha autoantibodies was 5 ng/ml. These antibodies were detected in 5 of 11 patients on the first hospital day. On the 21st hospital day, these antibodies were detected in all patients, and its level was increased compared with that on the first hospital day. IL-1 alpha autoantibodies that appeared in patients corresponded to that of IgG. The half life of exogenous autoantibodies was investigated following administration of autoantibody rich plasma obtained from healthy blood donors to 6 control patients (CP) and 6 progressive IPF patients. These autoantibody levels in their serum were less than 5 ng/ml before administration. Serum was obtained at the indicated time after administration of IL-1 alpha autoantibodies and the level of these autoantibodies in serum was measured, then the half life was calculated. Half life of exogenous IL-1 alpha autoantibodies in progressive IPF patients was significantly shorter than that in CP (71.3 +/- 31.8 hr vs 352.0 +/- 98.3 hr, p < 0.01). These findings suggested that IL-1 alpha autoantibodies were generated in response to the inflammatory process of rapidly progressive IPF and may act as a regulatory factor for IL-1 alpha.
Collapse
|
248
|
Hanyu H, Asano T, Sakurai H, Takasaki M, Shindo H, Abe K. Magnetization transfer measurements of the hippocampus in the early diagnosis of Alzheimer's disease. J Neurol Sci 2001; 188:79-84. [PMID: 11489289 DOI: 10.1016/s0022-510x(01)00553-6] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
We measured magnetization transfer ratios (MTRs) of the hippocampus in 38 patients with Alzheimer's disease (AD), including very mild (Clinical Dementia Rating [CDR] 0.5, n=12), mild (CDR 1, n=14), and moderate stages (CDR 2, n=12), and in 21 healthy elderly control subjects. Medial temporal lobe atrophy was graded subjectively on a five-point scale by two observers blinded to clinical data. Compared with the controls, each of the AD groups, including the very mild group, had significant atrophy of the medial temporal lobe and a decrease in MTRs of the hippocampus. Logistic regression analysis revealed that the overall discrimination rate with MTR measurement and visual analysis of the atrophy was 85% and 73% between the control group and the CDR 0.5 group, 89% and 80% between the control group and the CDR 1 group, and 100% and 91% between the control group and the CDR 2 group, respectively. MTR measurements may provide additional information in detecting structural damage of the hippocampus of AD and be helpful in providing improved diagnosis and early detection of AD.
Collapse
|
249
|
Okabe T, Nakamura K, Asano T. Image quality of dry-processed film. COMPUTER METHODS AND PROGRAMS IN BIOMEDICINE 2001; 66:75-80. [PMID: 11378226 DOI: 10.1016/s0169-2607(01)00138-9] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Recently, a lot of dry film processors and its radiographic films have been favorably used in hospitals. We have evaluated the diagnostic capability and measured the image quality of these dry processed films, comparing it with those of conventional wet processed films. It is found that (1) dry processed film has almost the same diagnostic capability to that of wet processed film, and (2) dry film had strong absorption at 804 nm which brought a reddish color tone to dry film and gave radiologists problems in diagnosis. These situations have been improved through this study to some extent.
Collapse
|
250
|
Asano T, Akagi M, Tanaka K, Tamura J, Nakamura T. In vivo three-dimensional knee kinematics using a biplanar image-matching technique. Clin Orthop Relat Res 2001:157-66. [PMID: 11451115 DOI: 10.1097/00003086-200107000-00023] [Citation(s) in RCA: 158] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
A biplanar image-matching technique was developed and applied to a study of normal knee kinematics in vivo under weightbearing conditions. Three-dimensional knee models of six volunteers were constructed using computed tomography. Projection images of the models were fitted onto anteroposterior and lateral radiographs of the knees at hyperextension and every 15 degrees from 0 degrees to 120 degrees flexion. Knee motion was reconstructed on the computer. The femur showed a medial pivoting motion relative to the tibia during knee flexion, and the average range of external rotation associated with flexion was 29.1 degrees . The center of the medial femoral condyle translated 3.8 mm anteriorly, whereas the center of the lateral femoral condyle translated 17.8 mm posteriorly. This rotational motion, with a medially offset center, could be interpreted as a screw home motion of the knee around the tibial knee axis and a posterior femoral rollback in the sagittal plane. However, the motion of the contact point differed from that of the center of the femoral condyle when the knee flexion angle was less than 30 degrees. Within this range, medial and lateral contact points translated posteriorly, and a posterior femoral rollback occurred. This biplanar image-matching technique is useful for investigating knee kinematics in vivo.
Collapse
|