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Watanabe M, Sugano S, Togashi T, Imai J, Uchida K, Yamaguchi R, Tateyama S. Molecular cloning and phylogenetic analysis of canine beta-casein. DNA SEQUENCE : THE JOURNAL OF DNA SEQUENCING AND MAPPING 2001; 11:295-300. [PMID: 11092743 DOI: 10.3109/10425170009033246] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
A canine beta-casein cDNA was isolated from mammary tissue by polymerase chain reaction (PCR) using degenerate primers. It encodes 250 amino acids protein containing the conserved sequence motif of beta-casein. It showed the highest homology with snow-leopard (Uncia uncia (55-62% identity). It also showed 44-53% identity with human, 33-42%, identity with mouse, 29-37%, identity with rat, 43-53% identity with rabbit, 41-48% identity with pig, 44-51% identity with cattle and 44-50% identity with sheep. A 1.2-kb mRNA was detected in mammary tissue by Northern blot analysis. Phylogenetic analysis revealed that canine beta-casein formed a branch with lesser panda and snow leopard, which were grouped into carnivore.
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Imai J, Ghazizadeh M, Naito Z, Asano G. Immunohistochemical expression of T, Tn and sialyl-Tn antigens and clinical outcome in human breast carcinoma. Anticancer Res 2001; 21:1327-34. [PMID: 11396208] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/20/2023]
Abstract
BACKGROUND The extent of expression of reactive T (Thomsen-Friedenreich), Tn and sialyl-Tn antigens has been assumed to predict carcinoma aggressiveness. We studied the expression of T, Tn and sialyl-Tn antigens in a relatively large cohort of breast carcinoma patients with known long-term outcome to assess the clinical and biological significance of these antigens. MATERIALS AND METHODS T, Tn and sjalyl-Tn antigens were examined in 72 consecutive primary breast carcinomas by immunohistochemistry using well defined monoclonal antibodies and their semiquantitative values were correlated with established clinicopathologic prognostic parameters of the disease to determine their relationship with long-term clinical outcome. RESULTS Of the 72 carcinomas, 63 (87.5%) each expressed T or Tn antigens, while 16 (22%) expressed sialyl-Tn antigens. Most carcinomas (81%) expressed more than one of the antigens simultaneously, being the most frequent combination T/Tn antigen expression. No significant correlation was noted between the expression of T, Tn and sialyl-Tn antigens (whether individually or in combination) and the prognostic parameters including patient age, disease stage, tumor size, lymph node status, nuclear and histologic grades, histologic types, hormone receptor status and menopausal status. Univariate survival analyses showed that disease stage, tumour size and lymph node metastasis were significant predictors of overall survival. Interestingly, a significant inverse correlation was found between the Tn antigen expression (p = 0.04), as well as the combined T/Tn (p = 0.03) and Tn/sialyl-Tn (p = 0.02) antigen expressions and long-term overall survival. In a multivariate Cox proportional hazard model, disease stage and a negative or low Tn antigen expression emerged as significant predictors of overall survival. CONCLUSION Our data suggested that the expression of T, Tn and sialyl-Tn antigens does not appear to predict the outcome of patients with breast carcinoma in a long-term run. Moreover, the findings signified a potential value for a negative or low Tn antigen expression in prognostic stratification of breast carcinomas.
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Watanabe M, Sugano S, Imai J, Yoshida K, Onodera R, Amin MR, Uchida K, Yamaguchi R, Tateyama S. Suppression of tumourigenicity, and induction of differentiation of the canine mammary tumour cell line MCM-B2 by sodium phenylacetate. Res Vet Sci 2001; 70:27-32. [PMID: 11170848 DOI: 10.1053/rvsc.2000.0437] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
The authors evaluated the cell growth inhibition, reduction of tumourigenicity, and differentiation-inducing effects of sodium phenylacetate (NaPA) on a canine mammary tumour cell line. Treatment of the canine mammary tumour cell line (MCM-B2) with NaPA lead to the arrest of cell growth. Sodium phenylacetate induced changes in the cells to non-malignant characteristics, as indicated by a reduction of colony formation in semi-solid agar and a decrease in tumour formation in athymic mice. Moreover, NaPA induced morphological changes from a spindle-shaped to an epithelial-like appearance, and significant accumulation of lipid droplets in the cytoplasm. Immunohistochemically, these treated cells reacted clearly with the antibody for keratin/cytokeratin. Sodium phenylacetate treatment increased the expression of the milk-specific genes alpha-lactalbumin and beta-casein. The results of this study warrant an evaluation of NaPA in a clinical trial to establish its possible value as adjunctive treatment of malignant canine mammary tumours.
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Abstract
Premolt, molting, and postmolt worms of Gnathostoma doloresi (Nematoda: Gnathostomatoidea) recovered from the stomach wall of naturally infected wild boars Sus scrofa leucomystax in Miyazaki, Japan, were examined morphologically. The only molt observed was that from the advanced third-stage to the adult stage. It is strongly suggested that the gnathostomes molt only once in the definitive host.
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Harada M, Imai J, Okuno S, Suzuki T. Macrophage-mediated activation of camptothecin analogue T-2513-carboxymethyl dextran conjugate (T-0128): possible cellular mechanism for antitumor activity. J Control Release 2000; 69:389-97. [PMID: 11102679 DOI: 10.1016/s0168-3659(00)00320-5] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Camptothecin (CPT) analogue T-2513-carboxymethyl (CM) dextran conjugate (T-0128) suppressed human tumor xenografts that were refractory to CPTs. This improvement was explained by its altered pharmacokinetics, but the cellular mechanism of action is still not clear. For this reason, in the present study we examined the determinants of T-0128 action at the cellular level. In vitro tests showed that T-0128 was inactive, indicating that the requirement for its activity lies in the release of linked T-2513, accompanied by the cellular uptake of the conjugate. The accumulation varied between cell lines: tumor cells, including Walker-256 carcinoma and B16 melanoma, showed only a marginal uptake and an undetectable drug release in the medium. In contrast, macrophage-like cells, such as J774.1, internalized T-0128 very efficiently, and liberated T-2513. With regard to the mode of accumulation, fluid-phase pinocytosis seems to be a key factor based on the followings: a similar cell-specificity existed in the uptake of FITC dextran, a marker of fluid-phase pinocytosis. Also, the macrophage uptake of T-0128 increased almost linearly with its medium concentration and was insensitive to dextran sulfate, a ligand for macrophage scavenger receptor. Comparative efficacy studies of T-0128 in the presence and absence of macrophages demonstrated that macrophages increased the efficacy of T-0128. The enhancement could be explained in terms of increases in the amount of released T-2513. Overall, these results lead us to the conclusion that T-0128 acts like a Trojan horse with the help of macrophages: T-0128 is taken up by macrophages in tumor tissues, and the liberated T-2513 kills tumor cells.
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Imai J, Yahara I. Role of HSP90 in salt stress tolerance via stabilization and regulation of calcineurin. Mol Cell Biol 2000; 20:9262-70. [PMID: 11094077 PMCID: PMC102183 DOI: 10.1128/mcb.20.24.9262-9270.2000] [Citation(s) in RCA: 98] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The role of HSP90 in stress tolerance was investigated in Saccharomyces cerevisiae. Cells showing 20-fold overexpression of Hsc82, an HSP90 homologue in yeast, were hypersensitive to high-NaCl or H-LiCl stresses. Hsc82-overexpressing cells appeared similar to calcineurin-defective cells in salt sensitivity and showed reduced levels of calcineurin-dependent gene expression. Co-overexpression of Cna2, the catalytic subunit of calcineurin, suppressed the hypersensitivity. Cna2 and Hsc82 coimmunoprecipitated from control cells grown under normal conditions but not from stressed cells. In contrast, coimmunoprecipitation was detected with Hsc82-overexpressing cells even after exposure to stresses. Cna2 immune complexes from stressed control cells showed a significant level of calcineurin activity, whereas those from stressed Hsc82-overexpressing cells did not. Treatment of extracts from Hsc82-overexpressing cells with Ca(2+)-calmodulin increased the calcineurin activity associated with Cna2 immune complexes. Geldanamycin, an inhibitor of HSP90 abolished the coimmunoprecipitation but did not activate calcineurin. When the expression level of Hsc82 decreased to below 30% of the normal level, cells also became hypersensitive to salt stress. In these cells, the amount of Cna2 was reduced, likely as a result of degradation. The present results showed that Hsc82 binds to and stabilizes Cna2 and that dissociation of Cna2 from Hsc82 is necessary for its activation.
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Mimoto T, Hattori N, Takaku H, Kisanuki S, Fukazawa T, Terashima K, Kato R, Nojima S, Misawa S, Ueno T, Imai J, Enomoto H, Tanaka S, Sakikawa H, Shintani M, Hayashi H, Kiso Y. Structure-activity relationship of orally potent tripeptide-based HIV protease inhibitors containing hydroxymethylcarbonyl isostere. Chem Pharm Bull (Tokyo) 2000; 48:1310-26. [PMID: 10993230 DOI: 10.1248/cpb.48.1310] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
We designed and synthesized a new class of peptidomimetic human immunodeficiency virus protease inhibitors containing a unique unnatural amino acid, allophenylnorstatine [Apns; (2S,3S)-3-amino-2-hydroxy-4-phenylbutyric acid], with a hydroxymethylcarbonyl isostere as the active moiety. From a structure-activity relationship study of HIV-1 protease inhibition, enzyme selectivity for other aspartyl proteases, the antiviral activity and pharmacokinetics in rats, 24c (KNI-227) and 24d (KNI-272, our first clinical candidate) were found to be selective and orally potent HIV protease inhibitors. Moreover, an improvement of the pharmacokinetic features of KNI-272 provided two long-lasting and highly bioavailable compounds (24g: JE-2178, 24h: JE-2179).
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Okuno S, Harada M, Yano T, Yano S, Kiuchi S, Tsuda N, Sakamura Y, Imai J, Kawaguchi T, Tsujihara K. Complete regression of xenografted human carcinomas by camptothecin analogue-carboxymethyl dextran conjugate (T-0128). Cancer Res 2000; 60:2988-95. [PMID: 10850447] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/16/2023]
Abstract
Clinically available camptothecins (CPTs), such as irinotecan (CPT-11) and topotecan, represent one of the most promising classes of antitumor agents, despite their toxicity. To improve their pharmacological profiles, a new macromolecular prodrug, denoted T-0128, was synthesized. This prodrug is a novel CPT analogue (T-2513)-carboxymethyl (CM) dextran conjugate via a triglycine spacer, with a molecular weight of Mr 130,000. This study was designed to test the concept that the rational design of a CPT-polymer conjugate would increase the efficacy of the parent drug. The in vivo antitumor study against Walker-256 carcinoma demonstrated that T-0128 was 10 times as active as T-2513, supporting this concept. Additionally, comparative efficacy studies of T-0128, T-2513, CPT-11, and topotecan were performed using a panel of human tumor xenografts in nude mice, showing the advantage of T-0128 over these CPTs. The maximal tolerated doses (MTDs) of T-0128, T-2513, and CPT-11 were comparable. Even a single i.v. injection of T-0128 at 6 mg/kg (based on the amount of T-2513 bound to CM dextran) induced complete regression of MX-1 mammary carcinoma. T-0128 at 10 mg/kg weekly for 3 weeks (one-tenth of its MTD) cured LX-1 lung carcinoma. Also, T-0128 below its MTD consistently cured or regressed St-4 gastric and HT-29 colorectal tumor xenografts that are highly refractory to CPTs. These demonstrate the broad range of therapeutic doses achieved with T-0128. Pharmacokinetic studies were performed to correlate the efficacy results obtained for T-0128 with plasma and tissue drug concentrations using Walker-256 tumor-bearing rats. Results showed that after i.v. administration of T-0128, the conjugate continued to circulate at a high concentration for an extended period, resulting in tumor accumulation. In the tumor, the sustained release of T-2513 occurred. In contrast, T-2513 disappeared rapidly from the body. The significant increases in the amount and exposure time of released T-2513 in the tumor explain well the enhanced efficacy of T-0128. In conclusion, this study indicated that T-0128 improved the potency of T-2513, demonstrating the proof of the above concept.
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Imai J, Ieiri I, Mamiya K, Miyahara S, Furuumi H, Nanba E, Yamane M, Fukumaki Y, Ninomiya H, Tashiro N, Otsubo K, Higuchi S. Polymorphism of the cytochrome P450 (CYP) 2C9 gene in Japanese epileptic patients: genetic analysis of the CYP2C9 locus. PHARMACOGENETICS 2000; 10:85-9. [PMID: 10739176 DOI: 10.1097/00008571-200002000-00011] [Citation(s) in RCA: 96] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Imai J, Watanabe M, Sasaki M, Yamaguchi R, Tateyama S, Sugano S. Induction of c-met proto-oncogene expression at the metastatic site. Clin Exp Metastasis 1999; 17:457-62. [PMID: 10651314 DOI: 10.1023/a:1006659515706] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
In metastatic processes, gene expression may variously alter through interactions between tumor and host stromal cells at the metastatic site. Using a tail vein injection-lung metastatic model and differential display, we analyzed alteration of gene expression in experimentally metastasized lesions. We found that expression of the c-met proto-oncogene was elevated in the lungs metastasized by MC-1 cells. The up-regulation of c-met was also observed in the lungs metastasized by B16 melanoma cells. In situ hybridization analysis revealed that the elevation of c-met expression apparently occurred in tumor cells but did not in lung stromal cells at the metastatic site. The c-Met protein was also highly expressed and phosphorylated. The upregulation of c-met appeared to be caused by induction of gene expression but not to be due to preferential selection of tumor cells highly expressing c-met. These findings suggest that the c-met proto-oncogene is up-regulated at the transcription level through some interactions between tumor and host stromal cells.
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Robinson NG, Guo L, Imai J, Toh-E A, Matsui Y, Tamanoi F. Rho3 of Saccharomyces cerevisiae, which regulates the actin cytoskeleton and exocytosis, is a GTPase which interacts with Myo2 and Exo70. Mol Cell Biol 1999; 19:3580-7. [PMID: 10207081 PMCID: PMC84150 DOI: 10.1128/mcb.19.5.3580] [Citation(s) in RCA: 157] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The Rho3 protein plays a critical role in the budding yeast Saccharomyces cerevisiae by directing proper cell growth. Rho3 appears to influence cell growth by regulating polarized secretion and the actin cytoskeleton, since rho3 mutants exhibit large rounded cells with an aberrant actin cytoskeleton. To gain insights into how Rho3 influences these events, we have carried out a yeast two-hybrid screen using an S. cerevisiae cDNA library to identify proteins interacting with Rho3. Two proteins, Exo70 and Myo2, were identified in this screen. Interactions with these two proteins are greatly reduced or abolished when mutations are introduced into the Rho3 effector domain. In addition, a type of mutation known to produce dominant negative mutants of Rho proteins abolished the interaction with both of these proteins. In contrast, Rho3 did not interact with protein kinase C (Pkc1), an effector of another Rho family protein, Rho1, nor did Rho1 interact with Exo70 or Myo2. Rho3 did interact with Bni1, another effector of Rho1, but less efficiently than with Rho1. The interaction between Rho3 and Exo70 and between Rho3 and Myo2 was also demonstrated with purified proteins. The interaction between Exo70 and Rho3 in vitro was dependent on the presence of GTP, since Rho3 complexed with guanosine 5'-O-(3-thiotriphosphate) interacted more efficiently with Exo70 than Rho3 complexed with guanosine 5'-O-(3-thiodiphosphate). Overlapping subcellular localization of the Rho3 and Exo70 proteins was demonstrated by indirect immunofluorescence. In addition, patterns of localization of both Exo70 and Rho3 were altered when a dominant active allele of RHO3, RHO3(E129,A131), which causes a morphological abnormality, was expressed. These results provide a direct molecular basis for the action of Rho3 on exocytosis and the actin cytoskeleton.
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Mamiya K, Ieiri I, Shimamoto J, Yukawa E, Imai J, Ninomiya H, Yamada H, Otsubo K, Higuchi S, Tashiro N. The effects of genetic polymorphisms of CYP2C9 and CYP2C19 on phenytoin metabolism in Japanese adult patients with epilepsy: studies in stereoselective hydroxylation and population pharmacokinetics. Epilepsia 1998; 39:1317-23. [PMID: 9860067 DOI: 10.1111/j.1528-1157.1998.tb01330.x] [Citation(s) in RCA: 134] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
PURPOSE The aim of this study was to clarify the effects of genetic polymorphisms of cytochrome P450 (CYP) 2C9 and 2C19 on the metabolism of phenytoin (PHT). In addition, a population pharmacokinetic analysis was performed. METHODS The genotype of CYP2C9 (Arg144/Cys, Ile359/Leu) and CYP2C19(*1, *2 or *3) in 134 Japanese adult patients with epilepsy treated with PHT were determined, and their serum concentrations of 5-(4-hydroxyphenyl)-5-phenylhydantoin (p-HPPH) enantiomers, being major metabolites of PHT, were measured. A population pharmacokinetic analysis (NONMEM analysis) was performed to evaluate whether genetic polymorphism of CYP2C9/19 affects the clinical use of PHT by using the 336 dose-serum concentration data. RESULTS The mean maximal elimination rate (Vmax) was 42% lower in the heterozygote for Leu359 allele in CYP2C9, and the mean Michaelis-Menten constants (Km) in the heterozygous extensive metabolizers and the poor metabolizers of CYP2C19 were 22 and 54%, respectively, higher than those without the mutations in CYP2C9/19 genes. (R)- and (S)-p-HPPH/PHT ratios were lower in patients with mutations in CYP2C9 or CYP2C19 gene than those in patients without mutations. CONCLUSIONS Although the hydroxylation capacity of PHT was impaired with mutations of CYP2C9/19, the impairment was greater for CYP2C9. In view of the clinical use of PHT, two important conclusions were derived from this population study. First, the serum PHT concentration in patients with the Leu359 allele in CYP2C9 would increase dramatically even at lower daily doses. Second, the patients with CYP2C19 mutations should be treated carefully at higher daily doses of PHT.
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Ruike M, Murase N, Imai J, Ishii C, Suzuki T, Kaneko K. Intrasolid Interfacial Fractality of a Less-Crystalline Solid. J Colloid Interface Sci 1998; 207:355-362. [PMID: 9792780 DOI: 10.1006/jcis.1998.5809] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Small angle X-ray scattering (SAXS) measurements have been carried out on pitch (PIT) and cellulose (CEL)-based activated carbon fibers (ACFs). In the higher angle region, the scattering intensity did not obey the classical Porod's law. This suggests that ACFs have a rough surface and their roughness is expressed by the concept of surface fractal. The surface fractal dimension was determined from SAXS for each ACF. ACFs were treated at high temperature in argon in order to control the nanographitic crystallinity. PIT and CEL lost their microporosity upon heat treatment above 1773 and 2073 K, respectively. These nonporous ACFs showed also a strong SAXS caused by the electron density difference at the interface between microcrystalline and amorphous phase. This interface also had a fractal dimension, which was defined as the interfacial fractal dimension. The surface or interfacial fractal dimension of ACF depended on the heating temperature. As the treating temperature increased, the surface or interfacial fractal dimension decreased from 2.8 to 2.0. Both PIT and CEL showed a similar temperature dependence on each other. The surface or interfacial fractal dimension was reduced with the growth of nanographites, and upon heating at 3173 K, the intrasolid interfacial fractal dimension became 2. Copyright 1998 Academic Press.
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Mamiya K, Ieiri I, Miyahara S, Imai J, Furuumi H, Fukumaki Y, Ninomiya H, Tashiro N, Yamada H, Higuchi S. Association of polymorphisms in the cytochrome P450 (CYP) 2C19 and 2C18 genes in Japanese epileptic patients. PHARMACOGENETICS 1998; 8:87-90. [PMID: 9511186 DOI: 10.1097/00008571-199802000-00012] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
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Oriuchi N, Miyamoto K, Hoshino K, Imai J, Takahashi Y, Sakai S, Shimada A, Endo K. 99Tcm-MAG3: a sensitive indicator for evaluating perfusion and rejection of renal transplants. Nucl Med Commun 1997; 18:400-4. [PMID: 9194080] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Radionuclide renography has a role in evaluating perfusion of transplanted kidneys. In the course of rejection, cortical perfusion decreases before urinary excretion changes. Based on the facts that 99Tcm-MAG3 has different pharmacokinetics and shows a higher kidney-to-background count ratio than 99Tcm-DTPA, we postulated that 99Tcm-MAG3 was a sensitive and reproducible agent to measure cortical perfusion of transplanted kidneys. To clarify the feasibility of using 99Tcm-MAG3 to measure the cortical perfusion index (CPI), sequential renography was performed using 99Tcm-DTPA and 99Tcm-MAG3 in 14 patients with stable renal transplants, who had changes in serum creatinine concentration of less than 50% between the two studies. The CPI was calculated with 99Tcm-DTPA and 99Tcm-MAG3 and these were then compared and correlated with concurrent serum creatinine concentration. The CPI with 99Tcm-MAG3 was 1.43 times that with 99Tcm-DTPA in patients with changes in serum creatinine concentration equal to or less than 20%, and regression analysis revealed that the difference in CPI was larger in patients with more severely decreased renal perfusion than in patients with normal or mildly decreased renal perfusion. This preliminary study has indicated that the CPI with 99Tcm-MAG3 is a sensitive index for detecting changes in renal function, and thus is a feasible indicator of cortical perfusion when evaluating the rejection of transplanted kidneys.
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Imai J, Hirayama Y, Kikuchi K, Kakinuma M, Watabe S. cDNA cloning of myosin heavy chain isoforms from carp fast skeletal muscle and their gene expression associated with temperature acclimation. J Exp Biol 1997; 200:27-34. [PMID: 9023993 DOI: 10.1242/jeb.200.1.27] [Citation(s) in RCA: 78] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
We have isolated cDNA clones encoding fast skeletal muscle myosin heavy chains of carp acclimated to 10, 20 and 30 degrees C for over 5 weeks. All clones covered at least the full length of L-meromyosin, the C-terminal part of the myosin molecule. Nucleotide sequence analysis on cDNA clones showed three types of 3' untranslated sequences, demonstrating that carp expresses at least three myosin heavy chain isoforms in fast skeletal muscle in an acclimation-temperature-dependent manner. cDNAs were identified which were the predominant types expressed in 10 degrees C- and 30 degrees C-acclimated fish, as well as an intermediate type present at all acclimation temperatures. Northern blot analysis using probes of three kinds of DNA fragments from the 3' untranslated region of carp acclimated to 10, 20 and 30 degrees C further confirmed the presence of acclimation-temperature-specific isoforms. In addition, it was found that mRNA levels of three isoforms were altered in an acclimation-temperature-dependent manner. When the deduced amino acid sequences of three types of carp L-meromyosin were compared with those of homoiotherms, the 30 degrees C-acclimated type was more similar to those of homoiotherms than was the 10 degrees C-acclimated type.
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Sato T, Iwamura M, Ohori M, Egawa S, Uchida T, Koshiba K, Imai J, Matsuura N. [Renal cell carcinoma in childhood: a case report]. HINYOKIKA KIYO. ACTA UROLOGICA JAPONICA 1996; 42:439-41. [PMID: 8741299] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
A case of renal cell carcinoma (RCC) in a teenage patient is reported. A 13-year-old girl visited our hospital with the complaint of dyspnea and right abdominal mass. CT scan and chest X-P revealed a right renal tumor with multiple lung metastasis. Wilms' tumor was suspected and a combination chemotherapy consisting of actinomycin D and vincristin was performed. Since the tumor was insensitive to these agents, open biopsy was done. The pathological findings showed clear cell renal cell carcinoma. Despite the administration of alpha interferon, 5-FU and cimetidine, the disease was progressive and the patient died 5 months after diagnosis. It is important to consider the possibility of renal cell carcinoma in teenage patients with a renal mass, since more than 40% of the renal tumors in this age group are renal cell carcinomas.
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Imai J, Yoshida I, Murayama K, Sakai Y, Shimizu H, Sumi T, Iguchi T, Kawai M, Yamaguchi S. Determination of the 8-methyl ether of xanthurenic acid in human serum by high-performance liquid chromatography with fluorescence detection. JOURNAL OF CHROMATOGRAPHY. B, BIOMEDICAL APPLICATIONS 1996; 679:204-7. [PMID: 8998563 DOI: 10.1016/0378-4347(95)00572-2] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
We developed a simple and sensitive assay for the 8-methyl ether of xanthurenic acid in serum by high-performance liquid chromatography with fluorescence detection (excitation at 340 nm, emission at 450 nm). The compound under study in serum samples was extracted with Sep-Pak C18 cartridge and the extract was applied to an octadecylsilane-bonded column (Nucleosil 5C18, 150 x 4 mm I.D.). The mobile phase used was a mixture of 0.05 M sodium acetate buffer (pH 6.0), containing 5 mM sodium 1-octanesulfonate and 0.1 mM Na2EDTA, and acetonitrile (93:7, v/v). The 8-methyl ether of xanthurenic acid from serum samples was sufficiently separated to be clearly distinguishable. The quantification limit was 2 x 10(-14) mol, which was sensitive enough to detect 8-methyl ether of xanthurenic acid in serum from normal subjects. The method was applied to samples from patients with deficiency in tryptophan metabolism, xanthurenic acid/3-hydroxy kynurenineuria and showed a striking elevation in serum 8-methyl ether of xanthurenic acid.
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Saiga A, Aono Y, Imai J, Kinoshita K, Orita S, Igarashi H. Presence of antibodies to p21X and/or p27rex proteins in sera from human T-cell leukemia virus type I-infected individuals. J Virol Methods 1996; 57:157-68. [PMID: 8801227 DOI: 10.1016/0166-0934(95)01979-0] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
The human T-cell leukemia virus type I (HTLV-I) pX gene encodes three nonstructural proteins, p40tax, p27rex and p21X. So far, natural antibodies to p27rex and/or p21X have not been found in sera from HTLV-I-infected individuals, although antibodies to p40tax have been found. Recently, the viral transcripts specific for these proteins were detected in fresh peripheral blood mononuclear cells from HTLV-I-infected individuals by the polymerase chain reaction coupled to reverse transcription, showing the in vivo expression of these proteins. We detected antibodies to p21X and p27rex by an enzyme-linked immunosorbent assay (ELISA) system using a recombinantly produced p21X protein as a common antigen, because p21X is identical to the C-terminal portion of p27rex. The sensitivity of the ELISA was determined to be approximately 100 times greater than that of Western blotting. From the analyzed sera of 31 ATL patients, 30 asymptomatic carriers, 18 HAM patients and 100 healthy donors, three specimens from one ATL patient and two carriers were found to be positive for anti-p21X/p27rex antibodies. The specificity of the ELISA reaction was confirmed by the competitive ELISA test with the highly purified recombinant p21X protein. As of result, we first determined the presence of anti-p21X/p27rex antibodies in a small percentage (3.8%) of the sera from HTLV-I-infected individuals. Even sera from the ATL patients, whose fresh PBMCs contained the transcripts for these proteins, were not found to contain these antibodies, suggesting that the immune response to these proteins is low in HTLV-I-infected humans.
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Imai J, Toh-e A, Matsui Y. Genetic analysis of the Saccharomyces cerevisiae RHO3 gene, encoding a rho-type small GTPase, provides evidence for a role in bud formation. Genetics 1996; 142:359-69. [PMID: 8852836 PMCID: PMC1206971 DOI: 10.1093/genetics/142.2.359] [Citation(s) in RCA: 65] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
RHO3 encodes a Rho-type small GTPase of the yeast Saccharomyces cerevisiae. We isolated temperature-sensitive alleles and a dominant active allele of RHO3. Ts- rho3 cells lost cell polarity during bud formation and grew more isotropically than wild-type cells at nonpermissive temperatures. In contrast, cells carrying a dominant active mutant RHO3 displayed cold sensitivity, and the cells became elongated and bent, often at the position where actin patches were concentrated. These phenotypes of the rho3 mutants strongly suggest that RHO3 is involved in directing the growing points during bud formation. In addition, we found that SRO6, previously isolated as a multicopy suppressor of rho3, is the same as SEC4. The sec4-2 mutation was synthetic lethal with temperature-sensitive rho3 mutations and suppressed the cold sensitivity caused by a dominant active mutant RHO3. The genetic interactions between RHO3 and SEC4, taken together with the fact that the Rab-type GTPase Sec4p is required to fuse secretory vesicles together with plasma membrane for exocytosis, support a model in which the Rho3p pathway modulates morphogenesis during bud growth via directing organization of the actin cytoskeleton and the position of the secretory machinery for exocytosis.
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96
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Tanaka K, Aiyama T, Imai J, Morishita Y, Fukatsu T, Kakumu S. Serum cryoglobulin and chronic hepatitis C virus disease among Japanese patients. Am J Gastroenterol 1995; 90:1847-52. [PMID: 7572907] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
OBJECTIVES Hepatitis C virus (HCV)-associated mixed cryoglobulins appear to be detected often in hepatitis C-related chronic liver disease. The association of the two phenomenon among Japanese patients is the subject of the present study. METHODS Serum levels of total hemolytic complement (CH50) and anti-C3d-binding immune complex, as well as the prevalence of cryoglobulins, were studied in 213 patients with chronic liver disease (hepatitis C, 155; hepatitis B, 58). Cryoprecipitates were tested for anti-HCV Ab and HCV RNA. RESULTS CH50 activity was significantly lower in patients with hepatitis C than in those with hepatitis B except in responders to interferon who showed a sustained loss of HCV RNA. Cryoglobulins were detected in 24 (37%) of 65 patients with hepatitis C; they generally consisted of polyclonal immunoglobulins but one case. Cryoglobulins were more frequently observed in cirrhotic patients and in those with a longer duration of disease. Cryoglobulinemia-related clinical signs such as vasculitis occurred in only three cases. Patients with cryoglobulins had lower CH50 activity and higher immune complex values than those without cryoglobulins. Anti-HCV Ab and HCV RNA were detected in all cryoprecipitates tested. CONCLUSIONS These findings suggest that HCV is a major cause of cryoglobulins and advanced liver damage. However, serum cryoglobulins with polyclonal immunoglobulins appear to be less frequent among Japanese patients than among those studied in Western countries.
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97
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Ito H, Ogawa T, Murayama M, Fujino K, Horii H, Imai J, Kobayashi H, Yamada S, Watanabe C, Ishiyama M. [Effects of 5-fluorouracil in shrinking residual gastric cancer: a case report]. Gan To Kagaku Ryoho 1995; 22:953-6. [PMID: 7794003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
The patient was a 79-year-old man who underwent extensive gastrectomy and Billroth-II reconstruction for gastric ulcer in 1974. He complained of heartburn in November, 1992, and endoscopy for the residual stomach revealed IIb + IIa-like lesion mainly in the posterior wall of the anastomosed site, which was diagnosed as well differentiated adenocarcinoma. As the patient refused to be operated, 150 mg/day of 5-FU was administered. For 4 months before he decided to undergo operation, 12.9 g of 5-FU was administered in total. After rehospitalization, endoscopy of the residual stomach showed shrinkage of the lesion, and biopsy revealed no malignant findings. The pathological examination after total resection of the residual stomach showed atypism, but no evidence to support malignancy. He has continued to be well without sign of recurrence for 1 year since the operation. The administration of 5-FU is widely used as preoperative adjuvant chemotherapy. This case it is rare for 5-FU to cause the disappearance or falling off of malignant cells.
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98
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Watabe S, Imai J, Nakaya M, Hirayama Y, Okamoto Y, Masaki H, Uozumi T, Hirono I, Aoki T. Temperature acclimation induces light meromyosin isoforms with different primary structures in carp fast skeletal muscle. Biochem Biophys Res Commun 1995; 208:118-25. [PMID: 7887920 DOI: 10.1006/bbrc.1995.1313] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Carp acclimated to 10 degrees C gave 69k, 66k, and 62kDa light meromyosin (LMM) fragments in SDS-PAGE, while fish acclimated to 30 degrees C gave 74k, 69k, 66k, and 62kDa fragments. The microsequence analysis revealed that the 69k and 66kDa components from the 10 degrees C-acclimated carp contained an N-terminal amino acid sequence different from that of 62kDa. The four fragments from the 30 degrees C-acclimated carp showed the same sequence as that of the 69k and 66kDa components from the 10 degrees C-acclimated carp, except that the 2nd amino acid, Ala, of the 10 degrees C-acclimated LMM was replaced by Thr. DNA fragments encoding an N-terminal region of LMM were amplified by PCR or reverse transcriptase-PCR, demonstrating that the two acclimated groups further contained several amino acids substituted.
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99
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Takezaki T, Tajima K, Komoda H, Imai J. Incidence of human T lymphotropic virus type I seroconversion after age 40 among Japanese residents in an area where the virus is endemic. J Infect Dis 1995; 171:559-65. [PMID: 7876601 DOI: 10.1093/infdis/171.3.559] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
To clarify how seroconversion after age 40 years contributes to the seroprevalence of human T lymphotropic virus type I (HTLV-I), Japanese residents were studied in an area of Kyushu in which HTLV-I is endemic. Cross-sectional data showed higher seroprevalences among subjects > or = 40 than in those < 40 years old (27.0% vs. 7.9%). The prevalence was also greater in women than men (25.5% vs. 17.6%). Six hundred subjects > or = 40 years old were tested during 1976-1993. Among 8 who seroconverted, 5 had an HTLV-seropositive spouse and 2 seroconverted after blood transfusions. The incidences per 1000 person-years of seroconversion in age groups 40-49, 50-59, and > or = 60 years were, respectively, 0.0, 0.0, and 3.3 (range, 1.38-5.13) in men and 0.0, 5.3 (range, 0.11-7.99), and 1.4 (range, 0.00-1.60) in women. The seroconversion incidence was insufficient to account for the rise of seroprevalence in those > or = 40 years old, especially among women. These results suggest that the high rate and sex discordance in HTLV-I seroprevalence after age 40 may depend mainly on the birth cohort effect for vertical or horizontal transmission.
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100
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Imai J, Murayama K, Kawai M, Yamaguchi S, Matsuura K. Determination of 8-methyl ether of xanthurenic acid in human urine by high-performance liquid chromatography. JOURNAL OF CHROMATOGRAPHY. B, BIOMEDICAL APPLICATIONS 1994; 661:149-53. [PMID: 7866542 DOI: 10.1016/0378-4347(94)00317-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
We developed a simple and sensitive assay for the urinary 8-methyl ether of xanthurenic acid (XA-OMe) by high-performance liquid chromatography with fluorescence detection (excitation at 340 nm; emission at 450 nm). Urine samples were diluted with 0.03 M potassium phosphate buffer (pH 6.0) and applied to an octadecylsilane-bonded column (Nucleosil 5C18, 150 x 4 mm I.D.). The mobile phase used was a mixture of this same buffer and acetonitrile (1000:140, v/v). Both direct injection of urine and solvent extraction prior to HPLC were tested and showed a good correlation and sensitivity, although the peak of XA-OMe was occasionally less distinguishable from close peaks in urine from normal controls by the direct injection method. The quantification limit was 5 x 10(-14) mol which was sensitive enough to detect XA-OMe in urine from normal subjects. The method was applied to samples from patients with a deficiency in tryptophan catabolism, xanthurenic acid/3-hydroxykynurenine-uria and showed a striking elevation in urinary XA-OMe excretion.
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