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Yamaguchi J. J Appl Glycosci (1999) 2003; 50:509-510. [DOI: 10.5458/jag.50.509] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022] Open
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Ngampanya B, Takeda T, Narangajavana J, Ikeda A, Yamaguchi J. Sugar Transporters Involved in Flowering and Grain Development of Rice. J Appl Glycosci (1999) 2003. [DOI: 10.5458/jag.50.237] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022] Open
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178
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Tateishi M, Ohashi K, Kobayashi K, Hashimoto T, Yamaguchi J, Fujioka H, Izawa K, Masada M. Interindividual variation in the ratio between plasma morphine and its metabolites in cancer patients. INTERNATIONAL JOURNAL OF CLINICAL PHARMACOLOGY RESEARCH 2003; 23:75-82. [PMID: 15018021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 04/29/2023]
Abstract
In 25 cancer patients treated with slow-release oral morphine and in 10 cancer patients treated with continuous infusion of morphine, plasma steady-state concentrations of morphine (M), morphine-3-glucuronide (M-3-G) and morphine-6-glucuronide (M-6-G) were determined by high-performance liquid chromatography. Blood samples were withdrawn at 0, 2 and 6 h after oral administration in patients treated with slow-release oral morphine and once or twice a day in patients treated with continuous infusion of morphine. In four cancer patients treated with continuous infusion of morphine, in order to analyze chronopharmacokinetic variability, the M-3-G/M ratio was observed at 12:00 h and 24:00 h. No significant changes were observed in M-3-G/M ratios and M-6-G ratios at 0, 2, and 6 h after oral administration of morphine. The M-3-G/M ratio (38.6 +/- 25.7) in the oral morphine group was significantly higher than that (15.3 +/- 12.9) in the continuous infusion group (p < 0.01). There was an approximately 10-fold interindividual variation in the M-3-G/M ratio both in the continuous infusion group and in the oral morphine group. These results suggest that the activity of UDP glucuronosyltransferase 2B7 in the intestinal metabolism of morphine may play an active part in a large interindividual variation in the ratio of metabolites to morphine. Further studies are needed to clarify this hypothesis.
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Ikeda A, Sonoda Y, Vernieri P, Perata P, Hirochika H, Yamaguchi J. The slender rice mutant, with constitutively activated gibberellin signal transduction, has enhanced capacity for abscisic acid level. PLANT & CELL PHYSIOLOGY 2002; 43:974-979. [PMID: 12354914 DOI: 10.1093/pcp/pcf115] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
The slender rice (slr1-1) mutant, carrying a lethal and recessive single mutation, has a constitutive gibberellin (GA)-response phenotype and behaves as if it were saturated with GAs [Ikeda et al. (2001) Plant Cell 13, 999]. The SLR1 gene, with sequence homology to members of the plant-specific GRAS gene family, is a mediator of the GA signal transduction process. In the slender rice, GA-inducible alpha-amylase was produced from the aleurone layer without applying GA. GA-independent alpha-amylase production in the mutant was inhibited by applying abscisic acid (ABA). Shoot elongation in the mutant was also suppressed by ABA, indicating that the slender rice responds normally to ABA. Interestingly, shoot ABA content was 10-fold higher in the mutant than in the wild type, while there was no difference in root ABA content. Expression of the Rab16A gene, which is known to be ABA inducible, was about 10-fold higher in shoots of the mutant than in those of the wild type. These results indicate that constitutive activation of the GA signal transduction pathway by the slr1-1 mutation promotes the endogenous ABA level.
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Okamoto M, Ogihara N, Kawamura W, Ebihara S, Takiguchi K, Morita T, Uchida R, Yamaguchi J, Sakai T, Okuda Y, Hayashi Y, Arakawa Y, Kikuchi M. Comparison of insulinotrophic actions of nateglinide with glibenclamide dissociated from absorption in conscious dogs. Metabolism 2002; 51:575-81. [PMID: 11979388 DOI: 10.1053/meta.2002.31981] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Nateglinide is more rapidly absorbed than glibenclamide. Therefore, the different absorption kinetics of both drugs were eliminated by intraportal administration in conscious fasted dogs. The plasma insulin profiles were compared under similar kinetic changes in plasma drug concentrations. After a priming dose of nateglinide (1 mg/kg. 5 min) or glibenclamide (40 microg/kg. 5 min), plasma drug concentrations reached a peak at 4 minutes (nateglinide, 80 +/- 5 micromol/L, n = 6 and glibenclamide, 263 +/- 60 nmol/L, n = 6) followed by a sustained level at approximately 30% of the peak concentration at 30 minutes. Nateglinide led to a rapid and constant reduction in arterial glucose of approximately 30% basal, while glibenclamide promoted a gradual decrease to approximately 50% basal at 120 minutes. An increase in plasma insulin level by nateglinide of 4 times basal (218 +/- 58 pmol/L v 47 +/- 3 pmol/L, P <.05, n = 6) occurred at 6 to 10 minutes followed by sustained release of 1.4 times basal (67 +/- 15 pmol/L, n = 6). The insulin surge was more than doubled (484 +/- 209 pmol/L, n = 6) under a euglycemic clamp. Insulin release by glibenclamide increased gradually reaching 10-fold basal (449 +/- 166 pmol/L, n = 6) at 60 minutes. This was not enhanced during a euglycemic clamp. Lowering the primed doses of nateglinide resulted in a diminished peak plasma insulin concentration. In contrast, glibenclamide caused only a slower increase, but eventually reaching a similar peak. By increasing the continuous infusion of nateglinide, the sustained insulin release was not altered. Glibenclamide, but not nateglinide, evoked prompt and sustained insulin release in the continuing presence of the other. These results are consistent with the concept that nateglinide produces a quick, but very short-lived, interaction with sulfonylurea (SU)-receptors on plasma membrane by free access of the drug from the cell exterior. In contrast, glibenclamide promotes a slow and longer interaction with the receptor by distribution of the drug into the cell inferior. We conclude, therefore, that not only the different kinetics of gastrointestinal (GI) absorption, but also the inherent difference in the interaction with beta cells is attributed to the different insulin release characteristics between nateglinide and glibenclamide in vivo.
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Hashimoto S, Narita S, Kasahara H, Shirai K, Kobayashi T, Takanishi A, Sugano S, Yamaguchi J, Sawada H, Takanobu H, Shibuya K, Morita T, Kurata T, Onoe N, Ouchi K, Noguchi T, Niwa Y, Nagayama S, Tabayashi H, Matsui I, Obata M, Matsuzaki H, Murasugi A, Kobayashi T, Haruyama S, Okada T, Hidaki Y, Taguchi Y, Hoashi K, Morikawa E, Iwano Y, Araki D, Suzuki J, Yokoyama M, Dawa I, Nishino D, Inoue S, Hirano T, Soga E, Gen S, Yanada T, Kato K, Sakamoto S, Ishii Y, Matsuo S, Yamamoto Y, Sato K, Hagiwara T, Ueda T, Honda N, Hashimoto K, Hanamoto T, Kayaba S, Kojima T, Iwata H, Kubodera H, Matsuki R, Nakajima T, Nitto K, Yamamoto D, Kamizaki Y, Nagaike S, Kunitake Y, Morita S. Auton Robots 2002; 12:25-38. [DOI: 10.1023/a:1013202723953] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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Imai Y, Hozawa A, Ohkubo T, Tsuji I, Yamaguchi J, Matsubara M, Michimata M, Hashimoto J, Fujiwara T, Nagai K, Kitaoka H, Satoh H, Hisamichi S. Predictive values of automated blood pressure measurement: what can we learn from the Japanese population - the Ohasama study. Blood Press Monit 2001; 6:335-9. [PMID: 12055412 DOI: 10.1097/00126097-200112000-00013] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
BACKGROUND Measurements of ambulatory blood pressure (ABP) and of home blood pressure (HBP) as an adjunct to casual/clinic blood pressure (CBP) measurements are currently widely used for the diagnosis and treatment of hypertension. We have monitored a rural cohort of people from the population of Ohasama, Japan, with respect to their prognosis and have previously reported that ABP and HBP are superior to CBP for the prediction of cardiovascular mortality. One reason that CBP is a poor predictor of prognosis is that it incorporates several biases, including the white-coat effect. METHODS AND RESULTS We examined the prognostic significance of white-coat hypertension for mortality and found that the relative hazard for the overall mortality of patients with white-coat hypertension was significantly lower than that for true hypertension. Short-term blood pressure variability has recently attracted attention as a cause of target-organ damage and cardiovascular complications. Our results confirmed that short-term blood pressure variability (as measured every 30 min) was independently associated with cardiovascular mortality. In addition, research has recently focused on isolated systolic hypertension and pulse pressure as independent risk factors for poor cardiovascular prognosis. The Ohasama study also clearly demonstrated that isolated systolic hypertension and increased pulse pressure, as assessed by HBP, were associated with an increase in the risk of cardiovascular mortality. Circadian blood pressure variation is characterized by a diurnal elevation and a nocturnal decline in blood pressure. We therefore compared morbidity from stroke between dippers (subjects who show an ordinal nocturnal dipping of blood pressure) and non-dippers (those with a diminished nocturnal dipping or nocturnal elevation of blood pressure [inverted dippers]) in the Ohasama study. The incidence of stroke increased with an increased length of observation in dippers using antihypertensive medication but not in non-dippers using antihypertensive medication. In contrast, the relative hazard for mortality increased in non-dippers and inverted dippers. These results suggest a cause-and-effect relationship for both dippers and non-dippers. CONCLUSION The Ohasama study showed that the level and variability of hypertension as assessed by ABP and HBP are independent predictors of cardiovascular mortality. It also demonstrated an independent association between the prognosis of hypertension and each component of ABP and HBP, indicating the prognostic significance of these blood pressure measurements.
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Abstract
A 41-year-old Japanese woman came to our clinic complaining of multiple edematous erythemas on the trunk and legs. The eruptions recurred periodically in association with the menstrual cycle. She had received oral progesterone therapy between 24 and 34 years of age. There were no abnormal values found in the routine and hormonal examinations, including progesterone and estrogen levels in serum and urine. After an intradermal skin test with progesterone, she had no reaction after 20 minutes but a positive reaction after 48 hours.
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Yamaguchi J, Mori H, Nishimura M. Biosynthesis and intracellular transport of glyoxysomal malate dehydrogenase in germinating pumpkin cotyledons. FEBS Lett 2001. [DOI: 10.1016/0014-5793(87)81516-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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185
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Tadakuma H, Yamaguchi J, Ishihama Y, Funatsu T. Imaging of single fluorescent molecules using video-rate confocal microscopy. Biochem Biophys Res Commun 2001; 287:323-7. [PMID: 11554728 DOI: 10.1006/bbrc.2001.5574] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Single fluorescent molecules in aqueous solution were imaged for the first time at video-rate using Nipkow disk-type confocal microscopy. Performance of this method was evaluated by imaging single kinesin molecules labeled with fluorescent dyes of tetramethylrhodamine (TMR) or IC5. Photodecomposition lifetimes of the fluorophores were approximately 10 s for TMR and approximately 2 s for IC5 under the incident laser power of 0.5 W/mm(2). Both the fluorescence intensity and the photobleaching rate were proportional to the laser power from 0.65 to 3 W/mm(2). 2D sliding movement of single kinesin molecules along microtubules on glass surface and 3D Brownian motion of individual kinesin molecules in viscous solution could be observed using this microscopy. These results indicated that this method could be applicable to the study of single molecular events in living cells at real time.
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Iwasaki K, Yamamoto M, Minami S, Komuta K, Yamaguchi J, Furui J, Kanematsu T. Human colon cancer produces a factor which induces the proliferation of venous endothelial cells. Oncol Rep 2001; 8:1057-61. [PMID: 11496316 DOI: 10.3892/or.8.5.1057] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
This study was performed to investigate whether colorectal cancers produce proliferative factors for venous endothelial cells, and whether the proliferative activity is related to basic FGF and VEGF and also to the clinicopathological findings. Surgically resected specimens of 17 colorectal cancer patients were fragmented and cultured, and the supernatant was collected. A human umbilical endothelial cell line (EA-hy 926 cells) was incubated with the supernatant. The proliferative activity was examined and the levels of basic FGF and VEGF were measured. The activities were found to be significantly related to VEGF, the depth of tumor invasion and the tumor stage.
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Yamaguchi J, Nemoto N, Sasaki T, Tokumasu A, Mimori-Kiyosue Y, Yagi T, Funatsu T. Rapid functional analysis of protein-protein interactions by fluorescent C-terminal labeling and single-molecule imaging. FEBS Lett 2001; 502:79-83. [PMID: 11583115 DOI: 10.1016/s0014-5793(01)02581-9] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Detection of protein-protein interactions is a fundamental step to understanding gene function. Here we report a sensitive and rapid method for assaying protein-protein interactions at the single-molecule level. Protein molecules were synthesized in a cell-free translation system in the presence of Cy5-puro, a fluorescent puromycin, using mRNA without a stop codon. The interaction of proteins thus prepared was visualized using a single-molecule imaging technique. As a demonstration of this method, a motor protein, kinesin, was labeled with Cy5-puro at an efficiency of about 90%, and the processive movement of kinesin along microtubules was observed by using total internal reflection microscopy. It took only 2 h from the synthesis of proteins to the functional analysis. This method is applicable to the functional analysis of various kinds of proteins.
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Yamaguchi J, Ohmichi M, Hasegawa M, Yoshida H, Ogawa N, Higuchi S. Identification of rat urinary and biliary metabolites of esonarimod, a novel antirheumatic drug, using liquid chromatography/electrospray ionization tandem mass spectrometry with postcolumn addition of 2-(2-methoxyethoxy)ethanol, a signal-enhancing modifier. Drug Metab Dispos 2001; 29:806-12. [PMID: 11353748] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/16/2023] Open
Abstract
The biotransformation of esonarimod (KE-298) [(+/-)-2-acetylthiomethyl-4-(4-methylphenyl)-4-oxobutanoic acid], a new antirheumatic drug, was investigated in rats. Urinary and biliary excretions within 24 h after oral administration of 5 mg/kg [(14)C]esonarimod accounted for 89 and 10% of the dose, respectively. Initial metabolite analysis by liquid chromatography/electrospray ionization tandem mass spectrometry with negative ion mode, in which a mobile phase of 20 mM ammonium acetate (pH 4.6)/methanol with gradient-elution mode was used, failed to obtain any structural information on most of the metabolites due to poor sensitivity. To overcome this problem, postcolumn addition of 2-(2-methoxyethoxy)ethanol, a powerful signal-enhancing modifier, to the mobile phase was used, allowing pronounced signal enhancement and structural elucidation of urinary and biliary metabolites. The results of metabolite analysis suggested that esonarimod is predominantly biotransformed to a pharmacologically active metabolite, thiol-containing deacetyl-esonarimod (M-I), and subsequently undergoes extensive metabolism, mainly S-methylation followed by the combination of S-oxidation and oxidative conversion of the aromatic methyl group. No disulfide metabolites, such as M-I-cysteine mixed disulfide and M-I-dimer, were found in the excreta. This finding is probably evidence supporting the notion that the reactivity of the thiol moiety of M-I with macromolecules in vivo is extremely lower than that of common thiol-containing drugs.
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Ikeda A, Ueguchi-Tanaka M, Sonoda Y, Kitano H, Koshioka M, Futsuhara Y, Matsuoka M, Yamaguchi J. slender rice, a constitutive gibberellin response mutant, is caused by a null mutation of the SLR1 gene, an ortholog of the height-regulating gene GAI/RGA/RHT/D8. THE PLANT CELL 2001; 13:999-1010. [PMID: 11340177 PMCID: PMC135552 DOI: 10.1105/tpc.13.5.999] [Citation(s) in RCA: 473] [Impact Index Per Article: 20.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/23/2000] [Accepted: 03/07/2001] [Indexed: 05/18/2023]
Abstract
The rice slender mutant (slr1-1) is caused by a single recessive mutation and results in a constitutive gibberellin (GA) response phenotype. The mutant elongates as if saturated with GAs. In this mutant, (1) elongation was unaffected by an inhibitor of GA biosynthesis, (2) GA-inducible alpha-amylase was produced by the aleurone layers without gibberellic acid application, and (3) endogenous GA content was lower than in the wild-type plant. These results indicate that the product of the SLR1 gene is an intermediate of the GA signal transduction pathway. SLR1 maps to OsGAI in rice and has significant homology with height-regulating genes, such as RHT-1Da in wheat, D8 in maize, and GAI and RGA in Arabidopsis. The GAI gene family is likely to encode transcriptional factors belonging to the GRAS gene superfamily. DNA sequence analysis revealed that the slr1-1 mutation is a single basepair deletion of the nuclear localization signal domain, resulting in a frameshift mutation that abolishes protein production. Furthermore, introduction of a 6-kb genomic DNA fragment containing the wild-type SLR1 gene into the slr1-1 mutant restored GA sensitivity to normal. These results indicate that the slr1-1 mutant is caused by a loss-of-function mutation of the SLR1 gene, which is an ortholog of GAI, RGA, RHT, and D8. We also succeeded in producing GA-insensitive dwarf rice by transforming wild-type rice with a modified SLR1 gene construct that has a 17-amino acid deletion affecting the DELLA region. Thus, we demonstrate opposite GA response phenotypes depending on the type of mutations in SLR1.
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Onda M, Yamaguchi J, Hanada K, Asami Y, Ikeda H. Role of DNA ligase in the illegitimate recombination that generates lambdabio-transducing phages in Escherichia coli. Genetics 2001; 158:29-39. [PMID: 11333216 PMCID: PMC1461634 DOI: 10.1093/genetics/158.1.29] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
We studied the role of DNA ligase in illegitimate recombination in Escherichia coli. A temperature-sensitive mutation in the lig gene reduced the frequency with which lambdabio-transducing phages were generated to 10-14% of that of wild type under UV irradiation. Reintroduction of the lig gene into this mutant restored the frequency of recombinant phage generation to that of wild type. Furthermore, overexpression of DNA ligase enhanced illegitimate recombination by 10-fold with or without UV irradiation. In addition, when DNA ligase was present in only limited amounts, UV-induced or spontaneous illegitimate recombination occurred exclusively at hotspot sites that have relatively long sequences of homology (9 or 13 bp). However, when DNA ligase was overexpressed, most of the illegitimate recombination took place at non-hotspot sites having only short sequences of homology (<4 bp). Thus, the level of ligase activity affects the frequency of illegitimate recombination, the length of sequence homology at the recombination sites, and the preference for recombination at hotspots, at least after UV irradiation. These observations support our hypothesis that the illegitimate recombination that generates lambdabio-transducing phages is mediated by the DNA break-and-join mechanism.
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Yamaguchi J, Yamamoto M, Komuta K, Fujioka H, Furui JI, Kanematsu T. Hepatic resections for bilobar liver metastases from colorectal cancer. JOURNAL OF HEPATO-BILIARY-PANCREATIC SURGERY 2001; 7:404-9. [PMID: 11180862 DOI: 10.1007/s005340070036] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/07/2000] [Accepted: 04/26/2000] [Indexed: 01/11/2023]
Abstract
The present study was performed to assess survival benefits in patients who underwent a hepatic resection for isolated bilobar liver metastases from colorectal cancer. Thirty-eight patients underwent a curative hepatic resection for isolated colorectal liver metastasis. Among them, 11 patients had bilobar liver metastases and 19 had a solitary metastasis. The remaining 8 patients had unilobar multiple lesions. We investigated survival in two groups those with bilobar and those with solitary metastatic tumors. Survival and disease-free survival were 36% and 18% at 5 years, respectively, in the patients with bilobar liver metastases, while these survivals were 43% and 34% in the patients with solitary liver metastasis. In the 38 patients, repeated hepatic resections were performed in 15 patients with recurrent liver disease. The 5-year survival and disease-free survival rates for these patients were 38% and 27%, respectively, after the second hepatic resections. Of the 11 patients with bilobar liver metastases, 5 underwent a repeated hepatic resection, and they all survived for over 42 months. Based on our observations, a hepatic resection was thus found to be effective even in selected patients with either bilobar nodules or recurrence in the remnant liver.
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192
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Mitsunaga S, Kawakami O, Numata T, Yamaguchi J, Fukui K, Mitsui T. Polymorphism in rice amylases at an early stage of seed germination. Biosci Biotechnol Biochem 2001; 65:662-5. [PMID: 11330685 DOI: 10.1271/bbb.65.662] [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: 11/08/2022]
Abstract
A polymorphism in rice amylases at an early stage of seed germination is analyzed by zymogram. In non-glutinous cultivars of rice, alpha-amylase isozymes are mainly confirmed in germinating seeds. However, in glutinous cultivars, beta-amylase isozymes, which are not confirmed in nonglutinous cultivars, make up the major part of the total amylase activity and the expression of alpha-amylases are repressed.
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Yamaguchi J, Hachiuma K, Kimura Y, Ogawa N, Higuchi S. Highly sensitive determination of TS-962 (HL-004), a novel acyl-CoA:cholesterol acyltransferase inhibitor, in rat and rabbit plasma by liquid chromatography and atmospheric pressure chemical ionization-tandem mass spectrometry combined with a column-switching technique. JOURNAL OF CHROMATOGRAPHY. B, BIOMEDICAL SCIENCES AND APPLICATIONS 2001; 750:99-108. [PMID: 11204228 DOI: 10.1016/s0378-4347(00)00437-0] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
A quantitative bioanalytical method with excellent specificity using liquid chromatography (LC) atmospheric pressure chemical ionization-tandem mass spectrometry (APCI-MS-MS) combined with a column-switching technique has been developed for the highly sensitive and reliable determination of TS-962 (HL-004), a novel acyl-CoA:cholesterol acyltransferase (ACAT) inhibitor, in rat and rabbit plasma. The method involves protein precipitation of a 25-microl aliquot of plasma sample with eight volumes of methanol containing a deuterium-labeled internal standard, the direct injection of a methanolic supernatant into the analytical instrumentation with no sample evaporation and reconstitution steps, automated on-line clean-up on a C18 short trapping column (10 mm x 4.0 mm I.D.) followed by separation on a C18 analytical column (50 mm x 4.6 mm I.D.), and detection with APCI-MS-MS using m/z 448 ([M+H]+) as a precursor ion and m/z 178 as a product ion in a selected reaction monitoring mode. The lower limit of quantification was 1 ng/ml, and good linearity of the calibration graph was obtained in the range of 1 to approximately 490 ng/ml with excellent reliability. The developed method enabled pharmacokinetic profiles to be determined for rats and rabbits with sequential plasma collection from an individual animal.
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Kobayashi K, Yamaguchi J, Mizoe A, Isomoto I, Koshiishi T, Izawa K, Kanematsu T. Successful treatment of bleeding due to ileal varices in a patient with hepatocellular carcinoma. Eur J Gastroenterol Hepatol 2001; 13:63-6. [PMID: 11204813 DOI: 10.1097/00042737-200101000-00012] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
This case report concerns a 62-year-old female who was known to have cirrhosis. An endoscopic examination showed no evidence of haemorrhaging due to either oesophageal or gastric varices. Angiographic studies demonstrated extravasation from the ileal varices. There was a prominent arterio-portal shunt in the liver, and the shunt was considered to be a contributing factor to induce portal hypertension and variceal bleeding in the ileum. Therefore, transcatheter arterial embolization was performed, but was unsuccessful. As a result, the patient underwent a laparotomy, and a dilatating ileocaecal vein and a communicating ovarian vein were selectively ligated. Following the procedure, the haemorrhaging stopped and she then recovered. The patient is doing well 21 months after surgery at the time of writing.
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Yamaguchi J, Matsuno Y, Hachiuma K, Ogawa N, Higuchi S. A strategy for quantitative bioanalysis of non-polar neutral compounds by liquid chromatography/electrospray ionization tandem mass spectrometry: determination of TS-962, a novel acyl-CoA:cholesterol acyltransferase inhibitor, in rabbit aorta and liver tissues. RAPID COMMUNICATIONS IN MASS SPECTROMETRY : RCM 2001; 15:629-636. [PMID: 11312514 DOI: 10.1002/rcm.274] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
A strategy for the sensitive and reliable quantitative determination of non-polar neutral compounds in biological matrices by liquid chromatography/electrospray ionization tandem mass spectrometry is described in the context of assay development for TS-962, a novel acyl-CoA:cholesterol acyltransferase (ACAT) inhibitor, in rabbit aorta and liver tissues. The electrospray ionization (ESI) mass spectrum of this compound with a mobile phase of water/acetonitrile did not give abundant [M + H]+ ions, but did give alkali metal cation adducts such as [M + Na]+, [M + CH3CN + Na]+ and [M + K]+ ions. The cationized species are acknowledged as unsuitable precursor ions for selected reaction monitoring (SRM) for various reasons, such as difficulty in obtaining characteristic product ions in low-energy collision-induced dissociation, and irreproducibility of the adduct-ion intensities. To overcome this problem, a solution of 3.4 mM trifluoroacetic acid in 2-propanol was added to the mobile phase as a postcolumn additive, resulting in a decrease of the undesirable adduct formation and significant enhancement of [M + H]+ ion intensity. An attempt was then made to prevent the matrix effect by employing a column-switching system, which allowed direct injection of a large volume of 2-propanolic tissue homogenate (950 microL) followed by sufficient clean-up, separation, and ESI-SRM on-line. This enabled development of a sensitive and reliable assay method for TS-962 in rabbit aorta and liver tissues in the concentration range of 5-500 ng/g wet tissue using a 25-mg aliquot of tissue sample. Application of this method to the determination of aortic TS-962 levels at 24 h after repeated oral administration of this compound (3 mg/kg) once a day for 12 weeks to 1% cholesterol-fed rabbits is also presented. Results showed that TS-962 is well distributed to both the thoracic and abdominal aorta tissues, at levels higher than the 50% inhibitory concentration value of this compound for microsomal ACAT activity from rabbit aorta.
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Dobashi A, Hamada M, Yamaguchi J. Molecular recognition by chiral cationic micellar and micelle-like aggregates in electrokinetic capillary chromatography. Electrophoresis 2001; 22:88-96. [PMID: 11197184 DOI: 10.1002/1522-2683(200101)22:1<88::aid-elps88>3.0.co;2-u] [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: 11/09/2022]
Abstract
We examined the enantiomer separation with micelles and a micelle-like polymer made with trimethylammonium-terminated surfactants all of whose hydrocarbon chains contain hydrogen bonding valinediamide moieties in electrokinetic chromatography (EKC). The surfactants used were 3-(N-dodecanoyl-L-valylamino)-propyltrimethylammonium bromide (surfactant 1) and 6-(N-nonanoyl-L-valylamino)hexyl-trimethylammonium bromide (surfactant 2); the micelle-like polymer was derived from 3-(N-10-undecenoyl-L-valyl)aminopropyltrimethylammonium bromide (surfactant 3). N-Acylamino acids and their isopropyl esters were separated with enantiomers with the same configuration as the chiral surfactant and which were retained to a greater extent than the counterparts in micelles. The micellar hydrophobic environment, in which amides function as hydrogen bonding sites with solutes, and ceased micellar kinetic association-dissociation with polymerization are discussed.
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197
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Mizoe A, Yamaguchi J, Azuma T, Fujioka H, Furui J, Kanematsu T. Transcatheter arterial embolization for advanced hepatocellular carcinoma resulting in a curative resection: report of two cases. HEPATO-GASTROENTEROLOGY 2000; 47:1706-10. [PMID: 11149037] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/18/2023]
Abstract
Transcatheter hepatic arterial embolization and lipiodolization have been reported to be effective palliative treatments for patients with unresectable hepatocellular carcinoma. We experienced 2 patients with advanced hepatocellular carcinoma which were initially considered to be unresectable due to the extreme extension of the primary lesions. Therefore, transcatheter hepatic arterial embolization with lipiodolization were selected as the treatments of choice. Thereafter, these tumors markedly decreased in size and, as a result, curative resections could subsequently be performed. The pathological examination of the resected specimens revealed necrosis and hyaline degeneration in the main tumors. Viable tumor cells, however, still remained adjacent to the main tumors. Such evidence indicated the limited efficacy of transcatheter hepatic arterial embolization with lipiodolization and the necessity of performing surgical treatment in combination with transcatheter hepatic arterial embolization with lipiodolization. Based on these findings, transcatheter hepatic arterial embolization with lipiodolization both appear to be a good mode of therapy for advanced hepatocellular carcinoma, and in selected patients, subsequent surgery can also be considered.
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198
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Yoneda Y, Akazawa M, Koizumi J, Takasaki M, Yamaguchi J, Tomoda A. Multi-effective properties of homogentisic acid revealed in reactions with human hemoglobin and human erythrocytic hemoglobin. Int J Hematol 2000; 72:318-24. [PMID: 11185987] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/19/2023]
Abstract
Homogentisic acid (HGA) causes oxidation of human oxyhemoglobin and reduction of methemoglobin. The rate of oxidation of oxyhemoglobin by HGA is greatly accelerated in the presence of myo-inositol hexakis-phosphate (P6-inositol) or superoxide dismutase (SOD), but is inhibited in the presence of catalase. The reduction rate of methemoglobin by HGA is accelerated in the presence of P6-inositol but is greatly inhibited in the presence of SOD. It is suggested that the semiquinone and quinone form of HGA and oxygen radicals may be involved in the mechanism of oxido-reductive reactions of human hemoglobin with HGA. In addition, a new anodic hemoglobin found by isoelectric focusing electrophoresis was produced during the reaction of oxyhemoglobin with HGA. When human erythrocytes were exposed to HGA for several hours at 37 degrees C (pH 7.4), the anodic oxyhemoglobin (HGA-modified hemoglobin) and its half met-form hemoglobin [(alpha3+beta2+)2 of HGA-modified hemoglobin] were produced in significant amounts. HGA-modified hemoglobin was stably purified and showed increased oxygen affinity, absence of titratable sulfhydryl groups, and the absorption spectrum of normal oxyhemoglobin. Our results demonstrate that HGA shows multiple effects on human hemoglobin and erythrocytic hemoglobin, which is consistent with the evidence that HGA is involved in various pathological conditions such as arthritis and carcinogenesis in humans.
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199
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Yoshida-Kato H, Ichikawa K, Yamaguchi J, Watanabe K, Ohsumi J, Yonehara S, Serizawa N. Cloning and expression of a novel murine anti-human Fas antibody. Biosci Biotechnol Biochem 2000; 64:1903-8. [PMID: 11055394 DOI: 10.1271/bbb.64.1903] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Agonistic anti-human Fas antibodies that can induce apoptosis are thought to have therapeutic effects for various diseases resulting from an abnormality of the Fas/FasL system. However, some anti-Fas antibodies show toxicity, and it is difficult to investigate their therapeutic and toxicological effect using animals because of their species specificity. We previously obtained a murine anti-human Fas mAb, HFE7A. HFE7A reacted with both human and murine Fas, and mitigated lymphadenopathy without any sign of hepatotoxicity in MRLgld/gld mice. It is suggested that humanized HFE7A would be a therapeutic treatment for various diseases resulting from an abnormality of the Fas/FasL system. Here we isolated the cDNAs that code for the heavy and light chains of HFE7A and identified the corresponding nucleotide sequences. The recombinant HFE7A was indistinguishable in binding and apoptosis-inducing activity to that from a hybridoma cell line. These data provide essential information for the humanization and clinical application of the humanized HFE7A.
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200
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Kubo T, Horii M, Yamaguchi J, Terauchi R, Wu Y, Hasegawa Y, Enoki Y, Tsuchihashi Y, Hirasawa Y. Radial magnetic resonance imaging and pathological findings of acetabular labrum in dysplastic hips. PATHOPHYSIOLOGY : THE OFFICIAL JOURNAL OF THE INTERNATIONAL SOCIETY FOR PATHOPHYSIOLOGY 2000; 7:171-175. [PMID: 10996510 DOI: 10.1016/s0928-4680(00)00048-1] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Radial MRI findings and pathological changes were comparatively examined in the acetabular labrum of 11 hips of 11 patients, who underwent total hip arthroplasty for osteoarthritis due to acetabular dysplasia. Diffuse high signal pattern on the radial MR images corresponded to histological degeneration of the labrum. High signal pattern which was equivalent to the synovial fluid, showed an intralabral tear. In the obscure areas of MR images, severe impairment of the labrum such as rupture, detachment, and displacement were found.
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