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Kudo Y, Liu KY, Kawado S, Hirano K. Elimination of extrinsic components overlapping lattice distortion variations of a silicon single crystal obtained by double-crystal X-ray topography. J Appl Crystallogr 2000. [DOI: 10.1107/s0021889899015484] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
Variations in lattice plane spacing and lattice plane orientation,i.e.Δd/dand Δα, reflect variations in lattice distortion in a single crystal. Double-crystal X-ray topography (DCT) using synchrotron radiation can be used to measure Δd/dand Δα of a silicon single crystal. However, both Δd/dand Δα measured using DCT are always overlapped by extrinsic components, showing particular long-range variations. The extrinsic components should be eliminated from the measured Δd/dand Δα for quantitative characterization of silicon single crystals. A sample-rotation and area-detector-traverse (RT) method, applicable to X-ray optics for DCT, has been newly developed. The extrinsic components are eliminated by modification of the intensity distribution on the X-ray topographs using the RT method. From theoretical considerations, it is confirmed that the extrinsic components are mainly due to the (+,−) non-parallel setting between the monochromator and the collimator, and a minute bend in the sample due to its physical restraint.
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152
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Takata T, Miyauchi M, Ogawa I, Kudo Y, Takekoshi T, Zhao M, Sato S, Nikai H, Komiyama K. Immunoexpression of transforming growth factor beta in desmoplastic ameloblastoma. Virchows Arch 2000; 436:319-23. [PMID: 10834533 DOI: 10.1007/s004280050453] [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: 11/30/2022]
Abstract
Desmoplastic ameloblastoma (DA) is an unusual subtype of ameloblastoma histologically characterized by the pronounced collagenized stroma. In the present study, the immunolocalization of transforming growth factor beta (TGF-beta), one of the most potent local factors for modulating extracellular matrix formation, was observed in DA in order to study its participation in the stromal desmoplasia. Seven cases of DA, including a "hybrid" lesion, were studied together with ten cases of ordinary follicular and plexiform ameloblastomas as the control. In contrast to ordinary ameloblastomas, marked immunoexpression was observed in all DAs but one. In the "hybrid" lesion, TGF-beta was not expressed in the area of follicular ameloblastoma but in that of DA. These results show that TGF-beta produced by tumor cells of DA plays a part in the desmoplastic matrix formation.
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153
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Kudo Y, Boyd CA, Sargent IL, Redman CW. Modulation of indoleamine 2,3-dioxygenase by interferon-gamma in human placental chorionic villi. Mol Hum Reprod 2000; 6:369-74. [PMID: 10729320 DOI: 10.1093/molehr/6.4.369] [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: 11/14/2022] Open
Abstract
The effect of interferon-gamma on indoleamine 2,3-dioxygenase, a tryptophan catabolizing enzyme, was studied in cultured human placental chorionic villi. The activity of indoleamine 2,3-dioxygenase was markedly stimulated by interferon-gamma in a time- and concentration-dependent manner. Interferon-alpha and interferon-beta also showed a slight stimulatory effect on indoleamine 2,3-dioxygenase activity. The level of indoleamine 2,3-dioxygenase mRNA expression (determined by reverse transcription-polymerase chain reaction) was also enhanced by interferon-gamma. Interleukin-4 showed a dose-dependent inhibitory effect on interferon-gamma-induced stimulation of indoleamine 2,3-dioxygenase activity and mRNA expression.
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154
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Kumagai T, Nagata T, Kudo Y, Fukuchi Y, Ebina K, Yokota K. Cytotoxic activity and cytokine gene induction of Asp-hemolysin to murine macrophages. NIHON ISHINKIN GAKKAI ZASSHI = JAPANESE JOURNAL OF MEDICAL MYCOLOGY 2000; 40:217-22. [PMID: 10536308 DOI: 10.3314/jjmm.40.217] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
We examined the effects of Asp-hemolysin from Aspergillus fumigatus Fresenius-Muramatsu strain on the viability and cytokine gene expression of mouse peritoneal macrophages. The cytotoxic activity of Asp-hemolysin to macrophages cultured in FCS-RPMI medium was increased in a dose-dependent manner. Treatment of Asp-hemolysin with N-ethylmaleimide or sulfo-N-hydroxy-sulfosuccinimide-acetate caused a remarkable loss of the cytotoxic activity, however, the cytotoxic activity of Asp-hemolysin to macrophages cultured in serum-free medium was significantly increased as compared with that in FCS-RPMI medium. As other biological activities of Asp-hemolysin, tumor necrosis factor-alfa (TNF-alfa), interleukin-1 beta(IL-l beta) and interleukin-1 alfa (IL-l alfa) mRNA expression were observed in macrophages cultured with 1 micro g/ml of Asp-hemolysin.
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155
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Kudo Y, Takata T, Ogawa I, Kaneda T, Sato S, Takekoshi T, Zhao M, Miyauchi M, Nikai H. p27Kip1 accumulation by inhibition of proteasome function induces apoptosis in oral squamous cell carcinoma cells. Clin Cancer Res 2000; 6:916-23. [PMID: 10741716] [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
Ubiquitin-mediated proteolysis controls intracellular levels of various cell cycle regulatory proteins, and its inhibition has been shown to induce apoptosis in proliferating cells. In the present study, we examined induction of apoptosis in oral squamous cell carcinoma (OSCC) cells by treatment with specific proteasome inhibitors, carbobenzoxy-L-leucyl-L-leucyl-L-norvalinal and lactacystin. In all three OSCC cell lines examined, apoptotic changes such as apoptotic body formation and DNA fragmentation were observed at various degrees after 24 h of the carbobenzoxy-L-leucyl-L-leucyl-L-norvalinal or lactacystin treatment. HSC2 cells showed the most prominent apoptotic changes among the cell lines examined and demonstrated the highest level of accumulation of p27Kip1 protein after the treatment with proteasome inhibitor. Reduced expressions of cyclin D1 and phospho pRb were also observed after the treatment with proteasome inhibitor. Moreover, 12 h of treatment with the proteasome inhibitor inhibited cdk2/cyclin E kinase activity and increased the ratio of the cell cycle population at the G1 phase. The proteasome inhibitor led to inhibition of cell cycle progression. In addition, activation of CPP32 and reduced expression of Bcl-2 were observed. Because apoptosis induced by the proteasome inhibitor was inhibited by treatment with antisense p27Kip1 oligonucleotide, accumulation of the p27Kip1 protein might play an important role in the apoptosis induced by proteasome inhibitor. The present results suggest that inhibition of proteasome function may be used as a possible target of novel therapy for OSCC.
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156
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Boyd CA, Deves R, Laynes R, Kudo Y, Sebastio G. Cationic amino acid transport through system y+L in erythrocytes of patients with lysinuric protein intolerance. Pflugers Arch 2000; 439:513-6. [PMID: 10764208 DOI: 10.1007/s004249900215] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
We test the hypothesis that lysinuric protein intolerance (LPI), a rare autosomal recessive defect of cationic amino acid transport, results from the absence of the recently described y+L amino acid transporter. We compare fluxes of lysine (1 microM) into erythrocytes of normal subjects with those of patients homozygous for the LPI mutation. No significant differences in fluxes through system y+L in normal or LPI cells were found, excluding the possibility that system y+L cannot be expressed in patients with LPI. Reasons for supposing that there may be tissue-specific processing of two recently described genes encoding the y+L transporter are discussed. Polymerase chain reaction measurement of expression of these two genes in an erythroleukemic cell line suggests that alternatively there may be an as-yet-unidentified additional member of this gene family.
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157
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Fujimoto J, Yasui W, Tahara H, Tahara E, Kudo Y, Yokozaki H, Tahara E. DNA hypermethylation at the pS2 promoter region is associated with early stage of stomach carcinogenesis. Cancer Lett 2000; 149:125-34. [PMID: 10737716 DOI: 10.1016/s0304-3835(99)00349-3] [Citation(s) in RCA: 57] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
pS2, a member of the trefoil peptide family, has been suggested to be a gastric-specific tumor suppressor. We examined the expression of pS2 in gastric carcinomas, adenomas and non-neoplastic mucosa and analyzed the DNA methylation in the pS2 promoter. Reduced expression of pS2 was frequently associated with well-differentiated adenocarcinomas. The CpG sites within the promoter region of the pS2 gene were methylated in pS2-negative gastric carcinoma cell lines whereas it was not in pS2-positive cell line. The promoter methylation was detected in gastric carcinoma tissues and intestinal metaplasia with reduced pS2 expression whereas none of the carcinomas with preserved pS2 expression showed the promoter methylation. These findings suggest that reduced expression of pS2 due to the promoter methylation may participate in an early stage of stomach carcinogenesis, especially of well differentiated type.
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158
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Liu X, Uchiyama M, Shibui K, Kim K, Kudo Y, Tagaya H, Suzuki H, Okawa M. Diurnal preference, sleep habits, circadian sleep propensity and melatonin rhythm in healthy human subjects. Neurosci Lett 2000; 280:199-202. [PMID: 10675795 DOI: 10.1016/s0304-3940(00)00793-x] [Citation(s) in RCA: 64] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
After 24-h sleep deprivation, 33 healthy young subjects entered the 10/20 min ultra-short sleep-wake schedule for 26 h. Melatonin rhythm was hourly assessed simultaneously. Results indicated that morning preference was significantly correlated with habitual sleep onset (r=-0.41, P=0.04), habitual sleep offset (r=-0.52, P=0.002), melatonin peak time (r=-0.36, P=0.04), and sleep propensity onset time (r=-0.36, P=0.04). The intervals between habitual sleep mid-point and melatonin peak time and between habitual sleep mid-point and sleep propensity onset time were significantly longer in morning-preference subjects than in evening-preference subjects (P<0.05). These findings suggest that the variance of diurnal preference may be related to differences in phase relations between habitual sleep timing and the circadian pacemaker.
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159
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Kudo Y, Boyd CA. Heterodimeric amino acid transporters: expression of heavy but not light chains of CD98 correlates with induction of amino acid transport systems in human placental trophoblast. J Physiol 2000; 523 Pt 1:13-8. [PMID: 10673541 PMCID: PMC2269792 DOI: 10.1111/j.1469-7793.2000.t01-1-00013.x] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
Abstract
1. Activity of amino acid transport and relative abundance of mRNAs encoding related transporters have been studied in parallel either before or following in vitro culture of explants of human placental chorionic villi. 2. Amino acid transport activities through systems L (1.9-fold), y+L (2.6-fold) and y+ (3.2-fold) were markedly enhanced following culture for 48 h. 3. Relative mRNA abundance (determined by reverse transcription-polymerase chain reaction) for the heavy chain of CD98 surface antigen and for the cationic amino acid transporter-1 were similarly stimulated (2.8-fold and 2.6-fold, respectively). In contrast, none of the mRNA levels for light chains of CD98 (system L-amino acid transporter-1, system L-amino acid transporter-2, system y+L-amino acid transporter-1 and system y+L-amino acid transporter-2) studied nor for the cationic amino acid transporter-2B were altered.
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160
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Liu X, Uchiyama M, Kim K, Okawa M, Shibui K, Kudo Y, Doi Y, Minowa M, Ogihara R. Sleep loss and daytime sleepiness in the general adult population of Japan. Psychiatry Res 2000; 93:1-11. [PMID: 10699223 DOI: 10.1016/s0165-1781(99)00119-5] [Citation(s) in RCA: 147] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
There are few epidemiological studies on sleep loss and daytime sleepiness in the general adult population of Japan. A total of 4000 adult people, aged 20 and over, were randomly drawn from five areas of Japan, and 3030 individuals were interviewed and completed a questionnaire including information about sleep duration and sleep problems. Overall, 29% slept less than 6 h at night, 23% reported having insufficient sleep, and 6% took sleep enhancing medications. The prevalence rates were 21% for symptoms of insomnia and 15% for excessive daytime sleepiness. Symptoms of insomnia were more prevalent in the elderly, whereas young people were more likely to report short sleep duration, subjective insufficient sleep and excessive daytime sleepiness. A multiple logistic regression model revealed that excessive daytime sleepiness had significant associations with young people, short sleep duration, insomnia symptoms, subjective insufficient sleep and sleep enhancing medication use. Short sleep duration was the strongest predictor of excessive daytime sleepiness. The findings indicate that sleep loss and excessive daytime sleepiness in the Japanese adult population are common, and comparable to those reported in Western countries. Excessive daytime sleepiness in the general adult population seems more likely to be attributed to short sleep duration.
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161
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Ebisawa T, Uchiyama M, Kajimura N, Kamei Y, Shibui K, Kim K, Kudo Y, Iwase T, Sugishita M, Jodoi T, Ikeda M, Ozeki Y, Watanabe T, Sekimoto M, Katoh M, Yamada N, Toyoshima R, Okawa M, Takahashi K, Yamauchi T. Genetic polymorphisms of human melatonin 1b receptor gene in circadian rhythm sleep disorders and controls. Neurosci Lett 2000; 280:29-32. [PMID: 10696804 DOI: 10.1016/s0304-3940(99)00981-7] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Recent studies suggest that melatonin 1b (Mel1b) receptor, as well as melatonin 1a (Mel1a) receptor, is involved in the modulation of circadian rhythms in mammals. Mutational analysis was performed in the entire coding region of the human Mel1b receptor gene using genomic DNA from sleep disorder subjects. We have identified two missense mutations, G24E and L66F. However, neither is likely to be associated with sleep disorders in our study population. One of the subjects with non-24-h sleep-wake syndrome carries missense mutations in both the Mel1a and Mel1b receptor genes.
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162
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Ishizuka B, Kudo Y, Amemiya A, Tanii M, Aoki T. Plasma catecholamine responses during laparoscopic gynecologic surgery with CO(2) insufflation. THE JOURNAL OF THE AMERICAN ASSOCIATION OF GYNECOLOGIC LAPAROSCOPISTS 2000; 7:37-43. [PMID: 10648737 DOI: 10.1016/s1074-3804(00)80007-9] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
STUDY OBJECTIVE To compare adrenergic-sympathetic responses during pelvic laparoscopic surgery with CO(2) insufflation with those during laparotomy. DESIGN. Prospective study (Canadian Task Force classification II-1). SETTING Tertiary care university hospital. PATIENTS Twenty-one infertile women with a clinical diagnosis of endometriosis. INTERVENTION Plasma norepinephrine (NE) and epinephrine (E) levels were measured in patients undergoing laparoscopic or open pelvic surgery. MEASUREMENTS AND MAIN RESULTS During laparoscopic surgery, increases in NE and E levels were correlated with arterial tension of CO(2) (PaCO(2)) and were greater in patients with a larger increase in PaCO(2) than in those undergoing laparotomy. Hemodynamic changes were also more evident during laparoscopic surgery, with larger PaCO(2) increases. CONCLUSION The PaCO(2) increases due to CO(2) insufflation are associated with adrenergic-sympathetic activation and hemodynamic changes during laparoscopic pelvic surgery.
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163
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Kudo Y, Takata T, Yasui W, Ogawa I, Miyauchi M, Takekoshi T, Tahara E, Nikai H. Reduced expression of cyclin-dependent kinase inhibitor p27Kipl is an indicator of malignant behavior in oral squamous cell carcinoma. Int J Oral Maxillofac Surg 2000. [DOI: 10.1034/j.1399-0020.2000.290120-3.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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164
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Kudo Y. [Application of organotypic cultures to researches on functional synapses]. TANPAKUSHITSU KAKUSAN KOSO. PROTEIN, NUCLEIC ACID, ENZYME 2000; 45:387-92. [PMID: 10707646] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/15/2023]
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165
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Kudo Y, Boyd CA. Human placental indoleamine 2,3-dioxygenase: cellular localization and characterization of an enzyme preventing fetal rejection. BIOCHIMICA ET BIOPHYSICA ACTA 2000; 1500:119-24. [PMID: 10564724 DOI: 10.1016/s0925-4439(99)00096-4] [Citation(s) in RCA: 81] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
In order to test the hypothesis (Munn, Zhou, Attwood, Bondarev, Conway, Marshall, Brown, Mellor, Science 281 (1998) 1191-1193) that localized placental tryptophan catabolism prevents immune rejection of the mammalian fetus, the cellular localization and characteristics of human placental indoleamine 2,3-dioxygenase (EC 1.13.11.42) were studied. The localization of indoleamine 2, 3-dioxygenase activity was determined quantitatively using cell fractionation by differential and discontinuous sucrose gradient centrifugation. Enzyme activity was looked for in isolated brush border microvillous plasma membranes of placental syncytiotrophoblast. We found that this membrane preparation (which showed a 32.4-fold purification from the starting homogenate with reference to the activity of a membrane marker enzyme, alkaline phosphatase (EC 3.1.3.1)) was strongly negatively enriched with indoleamine 2,3-dioxygenase (which showed a one twenty-fifth decrease in its specific activity). Placental indoleamine 2, 3-dioxygenase is thus not expressed in the maternal facing brush border membrane of syncytiotrophoblast. 1-Methyl-DL-tryptophan which was used by Munn et al. as a key experimental tool for inhibiting indoleamine 2,3-dioxygenase in the murine model showed a competitive inhibition of human placental indoleamine 2,3-dioxygenase with L-tryptophan. The hypothesis, based on experiments performed in mouse, may therefore be applicable to avoidance of immune rejection of the fetus in human pregnancy.
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Fukushima A, Kinouchi M, Kudo Y, Kanaya S. Statistical Analysis of Genomic Information : Long-Range Correlation in DNA Sequences. ACTA ACUST UNITED AC 2000. [DOI: 10.2142/biophys.40.s68_1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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167
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Hirasawa T, Nakamura T, Mizushima A, Morita M, Ezawa I, Miyakawa H, Kudo Y. Adverse effects of an active fragment of parathyroid hormone on rat hippocampal organotypic cultures. Br J Pharmacol 2000; 129:21-8. [PMID: 10694198 PMCID: PMC1621111 DOI: 10.1038/sj.bjp.0702949] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Abstract
Adverse effects of an active fragment of parathyroid hormone (PTH(1 - 34)), a blood Ca(2+) level-regulating hormone, were examined using rat hippocampal slices in organotypic culture. Exposure of cultured slice preparations to 0.1 microM PTH(1 - 34) for 60 min resulted in a gradual increase in the intracellular Ca(2+) concentration ([Ca(2+)](i)); this effect was most obvious in the apical dendritic region of CA1 subfield. When PTH(1 - 34) at a lower concentration (1 nM) was added to the culture medium and its toxic effects examined using a propidium iodide intercalation method, significant toxicity was seen 3 days after exposure and increased with time. Cells in the CA1 region seemed more vulnerable to the hormone than cells in other regions. At 1 week of exposure, the toxic effects were dose-dependent over the range of 0.1 pM to 0.1 microM, the minimum effective dose being 10 pM. The adverse effects were not induced either by the inactive fragment, PTH(39 - 84), or by an active fragment of PTH-related peptide (PTHrP(1 - 34)), an intrinsic ligand of the brain PTH receptor. The PTH(1 - 34)-induced adverse effects were significantly inhibited by co-administration of 10 microM nifedipine, an L-type Ca(2+) channel blocker, but not by co-administration of blockers of the other types of Ca(2+) channel. The present study demonstrates that sustained high levels of PTH in the brain might cause degeneration of specific brain regions due to Ca(2+) overloading via activation of dihydropyridine-sensitive Ca(2+) channels, and suggests that PTH may be a risk factor for senile dementia. British Journal of Pharmacology (2000) 129, 21 - 28
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168
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Yamamoto M, Takahashi H, Nakamura T, Hioki T, Nagayama S, Ooashi N, Sun X, Ishii T, Kudo Y, Nakajima-Iijima S, Kimchi A, Uchino S. Developmental changes in distribution of death-associated protein kinase mRNAs. J Neurosci Res 1999; 58:674-83. [PMID: 10561695 DOI: 10.1002/(sici)1097-4547(19991201)58:5<674::aid-jnr8>3.0.co;2-3] [Citation(s) in RCA: 48] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
Death-associated protein kinase (DAP-kinase) is Ca(2+)/calmodulin-dependent serine/threonine kinase that contains ankyrin repeats and the death domain. It has been isolated as a positive mediator of interferon-gamma-induced apoptotic cell death of HeLa cells. In order to reveal the physiological role of DAP-kinase, the tissue distribution and developmental changes in mRNA expression of DAP-kinase were investigated by Northern blot and in situ hybridization analyses. DAP-kinase mRNA was predominantly expressed in brain and lung. In brain, DAP-kinase mRNA had already appeared at embryonic day 13 (E13) and was, thereafter, detected throughout the entire embryonic period. High levels of expression were detected in proliferative and postmitotic regions within cerebral cortex, hippocampus, and cerebellar Purkinje cells. These findings suggest that DAP-kinase may play an important role in neurogenesis where a physiological type of cell death takes place. The overall expression of DAP-kinase mRNA in the brain gradually declined at postnatal stages, and the expression became restricted to hippocampus, in which different expression patterns were observed among rostral, central, and caudal coronal sections, suggesting that DAP-kinase may be implicated in some neuronal functions. Furthermore, it was found that the expression of DAP-kinase mRNA was increased prior to a certain cell death induced by transient forebrain ischemia, indicating a possible relationship between DAP-kinase and neuronal cell death.
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Kajimura N, Uchiyama M, Takayama Y, Uchida S, Uema T, Kato M, Sekimoto M, Watanabe T, Nakajima T, Horikoshi S, Ogawa K, Nishikawa M, Hiroki M, Kudo Y, Matsuda H, Okawa M, Takahashi K. Activity of midbrain reticular formation and neocortex during the progression of human non-rapid eye movement sleep. J Neurosci 1999; 19:10065-73. [PMID: 10559414 PMCID: PMC6782956] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/14/2023] Open
Abstract
To clarify the neural correlates and brain activity during the progression of human non-rapid eye movement (NREM) sleep, we examined the absolute regional cerebral blood flow (rCBF) during light and deep NREM sleep and during wakefulness in normal humans using positron emission tomography with H(2)(15)O. Relative changes in rCBF during light and deep NREM sleep in comparison to the rCBF during wakefulness were also analyzed. During light NREM sleep, the rCBF in the midbrain, in contrast to that in the pons and thalamic nuclei, did not decrease when compared to that during wakefulness, whereas rCBF decreased in the left medial frontal gyrus, left inferior frontal gyrus, and left inferior parietal gyrus of the neocortex. During deep NREM sleep, the rCBF in the midbrain tegmentum decreased, and there was a marked and bilateral decrease in the rCBF in all neocortical regions except for the perirolandic areas and the occipital lobe. There have been three groups of brain structures, each representing one type of deactivation during the progression of NREM sleep. The activity of the midbrain reticular formation is maintained during light NREM sleep and therefore represents a key distinguishing characteristic between light and deep NREM sleep. Selective deactivation of heteromodal association cortices, including those related to language, occurs with increasingly deep NREM sleep, which supports the recent theory that sleep is not a global, but it is a local process of the brain.
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170
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Takata T, Miyauchi M, Ito H, Ogawa I, Kudo Y, Zhao M, Sato S, Takekoshi T, Nikai H, Tanimoto K. Clinical and histopathological analyses of desmoplastic ameloblastoma. Pathol Res Pract 1999; 195:669-75. [PMID: 10549030 DOI: 10.1016/s0344-0338(99)80057-0] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Desmoplastic ameloblastoma (DA) is an unusual subtype of ameloblastoma characterized by pronounced desmoplastic stroma. There is, however, still argument whether DA is a distinct clinicopathologic entity. To enhance knowledge of DA, 7 cases of DA (7.9%) were retrieved from 89 ameloblastomas field in the Department of Oral Pathology, Hiroshima University School of Dentistry and analyzed clinicopathologically and histopathologically. The mean age of the patients with DA and non-DA at the time of the diagnosis was 40.6 +/- 5.9 years and 33.1 +/- 2.0 years, respectively. The male-to-female ratio was 2.5:1 in DA and 1.8:1 in non-DA. Four (57%) DAs were located in the maxilla where only 6% of the non-DA occurred. Interestingly, all DAs arose in the anterior/premolar area of the jaws and 6 cases were located mainly within the alveolus. None of the DA showed typical radiographic features of ameloblastoma. In 5 DAs, scattered radiopacities were observed in the radiolucent lesion and gave preoperative diagnoses of non-ameloblastomatous lesions or even osteosarcoma. All DAs showed pronounced desmoplastic stroma where there were compressed tumor islands usually lacking a peripheral layer of ameloblastic cells and a central zone of stellate reticulum. There was cystic change within the epithelial nests in 3 DAs and true glandular structures with mucus cells in a case of DA. Tumor islands often infiltrated into marrow spaces of surrounding bone. There was no capsule formation. Recurrence rate was 14% in DA and 20% in non-DA. The present study based on data of DA in the Japanese population supports that DA must be considered as a distinct clinicopathologic entity.
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171
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Zhao M, Takata T, Kudo Y, Sato S, Ogawa I, Wakida K, Uchida T, Nikai H. Biosynthesis of glycosaminoglycans and aggrecan by tumor cells in salivary pleomorphic adenoma: ultrastructural evidence. J Oral Pathol Med 1999; 28:442-50. [PMID: 10551741 DOI: 10.1111/j.1600-0714.1999.tb02104.x] [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: 11/29/2022]
Abstract
The present study attempted to discover the sites of synthesis of various glycosaminoglycans (GAGs) and aggrecan in salivary pleomorphic adenoma (PA) with the use of a highly sensitive and specific post-embedding immunogold-silver staining technique at the ultrastructural level. Silver particles representing various GAGs and aggrecan were found to accumulate frequently in the intercellular spaces of non-luminal cells in the epithelial clusters and were dispersed in the myxoid matrix of the mesenchyme-like areas. Furthermore, the non-luminal epithelial cells were demonstrated to contain immunopositive intracytoplasmic vesicles and vacuoles, some of which were of Golgi complex origin. In contrast, intracellular silver particles for hyaluronic acid were mostly attached to the inner surface of the cell membrane. These observations agree well with the current theories of the biosynthesis of GAGs and proteoglycans and provide direct evidence for the production of various GAGs and aggrecan by tumor epithelial cells of PA. Such findings support the ideas that in PA a loss of epithelium occurs by stromalization following epithelial secretion of extracellular matrix substances and transformation of epithelium to mesenchyme represents the basic principle of the tissue heterogeneity in this tumor.
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Takata T, Miyauchi M, Ogawa I, Zhao M, Kudo Y, Sato S, Takekoshi T, Nikai H, Tanimoto K. So-called 'hybrid' lesion of desmoplastic and conventional ameloblastoma: report of a case and review of the literature. Pathol Int 1999; 49:1014-8. [PMID: 10594850 DOI: 10.1046/j.1440-1827.1999.00972.x] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
So-called 'hybrid' lesion of ameloblastoma, which is composed of desmoplastic ameloblastoma and conventional follicular/plexiform ameloblastoma, is an unusual variant of ameloblastoma and only eight cases of 'hybrid' lesion have been published in the English literature. To enhance knowledge of this interesting tumor, we add a case of 'hybrid' lesion that occurred in the right mandible of a 48-year-old Japanese male. Radiographic examination disclosed a honeycomb appearance at the anterior alveolar region, combined with a unicystic radiolucency in the molar region of the mandibular body. Histologically, the former showed microscopic features of desmoplastic ameloblastoma and the latter those of follicular ameloblastoma with focal granular cell transformation. The lesion was enucleated with curettage of surrounding bone and the lesional cavity was marsupialized. Although tumor tissues reappeared at 3, 5, 7 and 14 months after the surgery, the patient has remained disease free for 11 years after the last vaporization by CO2 laser of the recurred tumor. Many more cases of 'hybrid' lesion are needed to clarify the clinicopathological, histopathological and biological characteristics of this interesting variant of ameloblastoma.
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173
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Morimura T, Kudo Y, Hiramoto Y, Ohashi K, Hattori M, Sugimoto C, Onuma M. Anti-viral and anti-tumor effects induced by an attenuated Marek's disease virus in CD4- or CD8-deficient chickens. Arch Virol 1999; 144:1809-18. [PMID: 10542027 DOI: 10.1007/s007050050705] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Abstract
By vaccination with an attenuated Marek's disease virus (MDV), strain CVI988, chickens are protected from the development of T cell lymphoma caused by an oncogenic MDV. To clarify the role of T lymphocyte subsets in the protection mechanisms of this vaccine, vaccinated chickens were depleted of T cell subsets by neonatal thymectomy and injections of monoclonal antibodies specific to chicken CD4 and CD8 molecules, and then challenged with an oncogenic MDV, strain Md5. The MDV titers rescued from CD8(+) T cells, which are the main targets for latent infection and subsequent transformation by MDV, was much higher in the CD8-deficient vaccinated chickens than in untreated vaccinated chickens at the early stage of the latent phase. However, the neonatal vaccination prevented lymphoma formation by strain Md5 even in either CD4(+) or CD8(+) T cell-depleted chickens. These results suggest that specific CD8(+) T cell responses induced by the MD vaccine play a crucial role in the prevention of MDV infection during the latent phase, but may not be essential for the prevention of lymphoma formation by an oncogenic MDV.
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174
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Okuyama K, Kiuchi S, Okamoto M, Narita H, Kudo Y. A novel Na+ and Ca2+ channel blocker, T-477, prevents brain edema following microsphere-induced permanent occlusion of cerebral arterioles in rats. JAPANESE JOURNAL OF PHARMACOLOGY 1999; 81:170-5. [PMID: 10591474 DOI: 10.1254/jjp.81.170] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
One of the most common acute complications of stroke is brain edema. Treatment of edema is recommended when the condition of the patients is deteriorating. The present study was undertaken to evaluate the effect of T-477 [(R)-(+)-2-(4-chlorophenyl)-2,3-dihydro-4-diethyl aminoacetyl-4H-1,4-benzorthiazine hydrochloride], a novel neuronal Na+ and Ca2+ channel blocker, on brain edema in rats. Cerebral ischemia was induced by intra-arterial infusion of 1000 microspheres into the forebrain of freely moving rats, resulting in brain edema. T-477 was intravenously infused continuously for 24 h or twice for 3 h with a 3-h interval between infusions immediately after microsphere injection. T-477 dose-dependently inhibited the increase in brain water content by both infusion procedures; the inhibition was statistically significant at doses of 25 mg/kg per 24 h and 14 mg/kg per 9 h. Additionally, infusion of T-477 at a dose of 14 mg/kg per 9 h significantly inhibited the decrease in K content and the increase in Ca content of the forebrain. In conclusion, T-477 prevents brain edema following microsphere-induced cerebral embolism in rats.
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175
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Kanaya S, Yamada Y, Kudo Y, Ikemura T. Studies of codon usage and tRNA genes of 18 unicellular organisms and quantification of Bacillus subtilis tRNAs: gene expression level and species-specific diversity of codon usage based on multivariate analysis. Gene 1999; 238:143-55. [PMID: 10570992 DOI: 10.1016/s0378-1119(99)00225-5] [Citation(s) in RCA: 295] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
We examined codon usage in Bacillus subtilis genes by multivariate analysis, quantified its cellular levels of individual tRNAs, and found a clear constraint of tRNA contents on synonymous codon choice. Individual tRNA levels were proportional to the copy number of the respective tRNA genes. This indicates that the tRNA gene copy number is an important factor to determine in cellular tRNA levels, which is common with Escherichia coli and yeast Saccharomyces cerevisiae. Codon usage in 18 unicellular organisms whose genomes have been sequenced completely was analyzed and compared with the composition of tRNA genes. The 18 organisms are as follows: yeast S. cerevisiae, Aquifex aeolicus, Archaeoglobus fulgidus, B. subtilis, Borrelia burgdorferi, Chlamydia trachomatis, E. coli, Haemophilus influenzae, Helicobacterpylori, Methanococcusjannaschii, Methanobacterium thermoautotrophicum, Mycobacterium tuberculosis, Mycoplasma genitalium, Mycoplasma pneumoniae, Pyrococcus horikoshii, Rickettsia prowazekii, Synechocystis sp., and Treponema pallidum. Codons preferred in highly expressed genes were related to the codons optimal for the translation process, which were predicted by the composition of isoaccepting tRNA genes. Genes with specific codon usage are discussed in connection with their evolutionary origins and functions. The origin and terminus of replication could be predicted on the basis of codon usage when the usage was analyzed relative to the transcription direction of individual genes.
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176
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Takata T, Kudo Y, Zhao M, Ogawa I, Miyauchi M, Sato S, Cheng J, Nikai H. Reduced expression of p27(Kip1) protein in relation to salivary adenoid cystic carcinoma metastasis. Cancer 1999; 86:928-35. [PMID: 10491517] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/14/2023]
Abstract
BACKGROUND Adenoid cystic carcinoma (ACC) is a malignant tumor of salivary gland origin. It tends to grow slowly but shows frequent recurrence and metastasis, ultimately with a poor outcome. Reduced expression of a cyclin-dependent kinase inhibitor, p27(Kip1), has been reported to correlate with poor survival for patients with various types of carcinoma. However, there has been no previous study reported of p27(Kip1) expression in ACC, to the authors' knowledge. METHODS To evaluate p27(Kip1) as a prognostic marker, the authors examined the immunohistochemical expression of p27(Kip1) protein in 29 ACCs and correlated its expression with clinicopathologic findings. Eleven pleomorphic adenomas (PAs) were also examined to compare the p27(Kip1) expression in benign and malignant salivary gland tumors. RESULTS All PAs expressed p27(Kip1) at high levels, whereas 83% of ACCs (24 of 29) showed reduced expression of this protein. Furthermore, the expression levels were significantly lower in ACCs with metastasis than in those without metastasis. The authors also examined the expression of p27(Kip1) in 2 ACC cell lines (ACCh and ACC3) by Northern and Western blot analysis to elucidate the possible mechanism of p27(Kip1) reduction in ACC. Both ACCh and ACC3 expressed p27(Kip1) mRNA, but ACCh did not produce p27(Kip1) protein. In ACCh, the expression of p27(Kip1) protein was induced by treatment with a proteasome inhibitor. CONCLUSIONS Overall, these findings suggest that reduced expression of p27(Kip1) may correlate with the development and progression of salivary ACC and can be an indicator of its malignant behavior. They also suggest that increased proteasome-mediated degradation may play an important role in this reduction of p27(Kip1) expression.
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177
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Ebisawa T, Kajimura N, Uchiyama M, Katoh M, Sekimoto M, Watanabe T, Ozeki Y, Ikeda M, Jodoi T, Sugishita M, Iwase T, Kamei Y, Kim K, Shibui K, Kudo Y, Yamada N, Toyoshima R, Okawa M, Takahashi K, Yamauchi T. Alleic variants of human melatonin 1a receptor: function and prevalence in subjects with circadian rhythm sleep disorders. Biochem Biophys Res Commun 1999; 262:832-7. [PMID: 10471411 DOI: 10.1006/bbrc.1999.1308] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
The human melatonin 1a (hMella) receptor gene was screened for mutations using genomic DNA samples from patients with circadian rhythm sleep disorders and control subjects by single strand conformational polymorphism analysis (SSCP). We found seven mutations, two of which predict amino acid changes R54W and A157V, respectively. The prevalence of the R54W variant and that of the A157V variant were several times more common in non-24-h sleep-wake syndrome subjects than among control subjects, although the incidence was not significant in our study group. When expressed in COS-7 cells, the R54W mutant receptor exhibited significantly reduced B(max) and slightly enhanced affinity (reduced K(d)) compared to the wild type receptor, while the A157V variant receptor showed similar binding characteristics to the wild type. The identification of variants in the hMella receptor will provide a useful tool for analyzing genetic predisposition toward various diseases related to melatonin function and to clarify the physiological role of melatonin receptors in humans.
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MESH Headings
- Alleles
- Amino Acid Substitution
- Base Sequence
- Circadian Rhythm
- Cloning, Molecular
- DNA Primers
- Genetic Variation
- Humans
- Melatonin/physiology
- Molecular Sequence Data
- Mutagenesis, Site-Directed
- Mutation, Missense
- Point Mutation
- Polymerase Chain Reaction
- Polymorphism, Single-Stranded Conformational
- Receptors, Cell Surface/chemistry
- Receptors, Cell Surface/genetics
- Receptors, Cell Surface/metabolism
- Receptors, Cytoplasmic and Nuclear/chemistry
- Receptors, Cytoplasmic and Nuclear/genetics
- Receptors, Cytoplasmic and Nuclear/metabolism
- Receptors, Melatonin
- Recombinant Proteins/chemistry
- Recombinant Proteins/metabolism
- Sleep Wake Disorders/genetics
- Sleep Wake Disorders/physiopathology
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178
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Maeda N, Horie Y, Sasaki Y, Ueta E, Adachi K, Nanba E, Kawasaki H, Kudo Y, Kondo M. A splicing mutation in the hydroxymethylbilane synthase gene in a Japanese family with acute intermittent porphyria. Clin Biochem 1999; 32:411-7. [PMID: 10667475 DOI: 10.1016/s0009-9120(99)00043-0] [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: 12/12/2022]
Abstract
OBJECTIVES Acute intermittent porphyria (AIP) is an autosomal dominant inherited disease caused by a decreased activity of hydroxymethylbilane synthase (HMBS). As far as the gene abnormalities of the HMBS, many different mutations have been reported. In this work, we investigated the presence of mutations in a Japanese family with AIP. DESIGN AND METHODS A 44-year-old Japanese male and nine members of his family were investigated. All of them were screened by traditional biochemical markers. Mutational analysis was performed using polymerase chain reaction-single strand conformation polymorphism method followed by DNA sequencing. A reliable restriction enzyme cleavage assay was established for the pedigree analysis. RESULTS The mutation was a splicing mutation, a C to G transversion at position -3 of the acceptor site of intron 11 of the HMBS gene, resulting in the exon 12 skipping. The patient is heterozygous for the mutation, and his father appeared to be the source of the mutant allele. This mutation created a new cleavage site of the Nla III restriction enzyme and could be screened by a amplified fragment from genomic DNA with digestion. Using this cleavage assay, an asymptomatic carrier in the family was definitively identified. CONCLUSIONS This mutation was first found among Japanese AIP patients, but happened to be the same as reported previously from Europe. A similarity of gene abnormality may suggest that those European and Japanese AIP families have a common ancestor. Molecular investigations on the family members should be applied not only for more accurate diagnosis, but also for understanding the molecular genetic heterogeneity underlying this dominantly inherited enzymopathy.
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179
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Yoshikawa H, Kudo Y, Ozawa K. [Double cortex syndrome]. NO TO SHINKEI = BRAIN AND NERVE 1999; 51:448-9. [PMID: 10396753] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/13/2023]
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180
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Kudo Y, Takata T, Ogawa I, Sato S, Nikai H. Expression of p53 and p21CIP1/WAF1 proteins in oral epithelial dysplasias and squamous cell carcinomas. Oncol Rep 1999; 6:539-45. [PMID: 10203588 DOI: 10.3892/or.6.3.539] [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: 11/06/2022] Open
Abstract
The expression of tumor suppressor gene, p53 and cyclin-dependent kinase inhibitor, p21 in oral epithelial dysplasia and oral squamous cell carcinoma (OSCC) was examined immunohistochemically and its relationship with clinicopathological findings was analyzed. Among 24 epithelial dysplasias, 4 cases (17%) expressed p53 protein and 23 cases (96%) expressed p21 protein. On the other hand, expression of p53 was observed in 64% of OSCCs, and expression of p21 was observed in 77% of OSCCs. In the analyses of the correlation between the expression of p53 and p21 in epithelial dysplasia and OSCC, 79% of epithelial dysplasias were p53-negative and p21-positive, compared to 25% of the OSCCs. p21 expression did not correlate with p53 expression. These results were also demonstrated in OSCC cell lines by western blot analysis. Cumulative survival rate of the patients p53-negative and p21-positive was higher than those p53-positive and p21-negative, those p53-negative and p21-negative and those p53-positive and p21-positive. These findings suggest that p53 expression and p21 negative expression may involve in neoplastic transformation of oral epithelium. In the present study, we did not observe correlation between the expression of p53 and p21 proteins in OSCC. p21 expression may be regulated by p53-independent pathways as well as p53-dependent ones. However, combination of the p21 and p53 expression may be useful as a prognostic marker.
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181
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Wang W, Watanabe M, Nakamura T, Kudo Y, Ochi R. Properties and expression of Ca2+-activated K+ channels in H9c2 cells derived from rat ventricle. THE AMERICAN JOURNAL OF PHYSIOLOGY 1999; 276:H1559-66. [PMID: 10330239 DOI: 10.1152/ajpheart.1999.276.5.h1559] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
H9c2 is a clonal myogenic cell line derived from embryonic rat ventricle that can serve as a surrogate for cardiac or skeletal muscle in vitro. Using whole cell clamp with H9c2 myotubes, we observed that depolarizing pulses activated slow outward K+ currents and then slow tail currents. The K+ currents were abolished in a Ca2+-free external solution, indicating that they were Ca2+-activated K+ currents. They were blocked by apamin, a small-conductance Ca2+-activated K+ (SK) channel antagonist (IC50 = 6.2 nM), and by d-tubocurarine (IC50 = 49.4 microM). Activation of SK channels exhibited a bell-shaped voltage dependence that paralleled the current-voltage relation for L-type Ca2+ currents (ICa,L). ICa,L exhibited a slow time course similar to skeletal ICa, L, were unaffected by apamin, and were only slightly depressed by d-tubocurarine. RT-PCR analysis of the mRNAs revealed that rSK3, but not rSK1 or rSK2, was expressed in H9c2 myotubes but not in myoblasts. These results suggest that rSK3 channels are expressed in H9c2 myotubes and are primarily activated by ICa,L directly or indirectly via Ca2+-induced Ca2+ release from sarcoplasmic reticulum.
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182
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Kudo Y, Kumagai T, Fukuchi Y, Ebina K, Yokota K. Binding of Asp-hemolysin from Aspergillus fumigatus to oxidized low density lipoprotein. Biol Pharm Bull 1999; 22:549-50. [PMID: 10375182 DOI: 10.1248/bpb.22.549] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Asp-hemolysin is a human low density lipoprotein (LDL) binding protein. We found evidence that Asp-hemolysin binds to oxidized LDL (oxLDL) as well as to LDL in a concentration-dependent manner. This result suggests that Asp-hemolysin is a novel protein, which shares binding abilities to LDL and oxLDL.
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183
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Yamada K, Hisatsune T, Uchino S, Nakamura T, Kudo Y, Kaminogawa S. NMDA receptor mediated Ca2+ responses in neurons differentiated from p53-/- immortalized Murine neural stem cells. Neurosci Lett 1999; 264:165-7. [PMID: 10320040 DOI: 10.1016/s0304-3940(99)00134-2] [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: 11/16/2022]
Abstract
NMDA receptors play important roles in brain formation by taking part in synaptogenesis and apoptosis. In the present study, the expression of NMDA receptors was analyzed in a neural stem cell line, MSP-1, which lacks p53. p53 is a transcription factor involved in excitotoxic neuronal apoptosis. It is quite likely that p53-mediated transcription control affects the expression of NMDA receptors inducing intracellular Ca2+ signaling after neuronal differentiation and is essential for neural development. By means of calcium digital imaging, NMDA receptor-mediated Ca2+ responses were detected from cultured neurons differentiated from neural stem cells which lack p53. This result implies that p53-related apoptosis is not due to NMDA receptor expression.
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184
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Shibui K, Uchiyama M, Okawa M, Kudo Y, Kim K, Kamei Y, Hayakawa T, Akamatsu T, Ohta K, Ishibashi K. Diurnal fluctuation of sleep propensity across the menstrual cycle. Psychiatry Clin Neurosci 1999; 53:207-9. [PMID: 10459690 DOI: 10.1046/j.1440-1819.1999.00489.x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Most women experience sleep changes across the menstrual cycle. We applied the ultra-short sleep-wake schedule to healthy females to compare their 24-h sleep propensity rhythms in the follicular and luteal phases. The daytime (09.00-16.30 h) subjective sleepiness and the number of slow wave sleep-containing nap trials increased in the luteal phase compared to the follicular phase, but the mean sleep propensity did not change. During the periods of 17.00-00.30 h and 01.00-08.30 h there were no differences between the two phases. These results suggest that increased daytime sleepiness in the luteal phase may be related to brain mechanisms controlling slow wave sleep.
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185
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Kudo Y, Horikawa Y, Noda T, Eguchi I, Watanabe Y, Wakabayashi K. [The clinical features of patients with probable dementia with Lewy bodies--report of 4 cases]. Rinsho Shinkeigaku 1999; 39:423-30. [PMID: 10391967] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/13/2023]
Abstract
Recently, McKeith et al. proposed criteria for the clinical diagnosis of dementia with Lewy bodies (DLB). In our study the clinical features of four patients with progressive dementia, visual hallucinations, delusions, and parkinsonism were compatible with those of DLB. To evaluate the neurological and psychiatric features, responses to medications, magnetic resonance imaging (MRI), and single-photon emission computed tomography (SPECT) in patients with DLB, we compared the above DLB patients with age- and gender-matched Parkinson's disease patients showing no signs of dementia. Our DLB patients presented with mild tremor, moderate rigidity and akinesia, severe constitutional dysfunction and recurrent visual hallucinations and delusions. These psychiatric symptoms became worse by anticholinergic agents and dopamine agonists and were difficult to control using neuroleptic medications. MRI revealed atrophy of the cerebrum to be more accentuated in the parietal region. SPECT demonstrated hypoperfusion in the parietal and occipital lobes. These findings suggest that parietal lobe dysfunction is a feature of DLB. It may, therefore, be concluded from this study that brain MRI and SPECT are useful in the clinical diagnosis of DLB, and that great caution should be taken when prescribing longacting dopamine agonists and neuroleptics to such patients.
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186
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Murasaki M, Yamauchi T, Yagi G, Nakajima T, Nakane Y, Kudo Y. [Early phase II study of quetiapine fumarate on schizophrenia]. NIHON SHINKEI SEISHIN YAKURIGAKU ZASSHI = JAPANESE JOURNAL OF PSYCHOPHARMACOLOGY 1999; 19:53-66. [PMID: 10464776] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/13/2023]
Abstract
The efficacy and safety of quetiapine fumurate in the treatment of patients with schizophrenia were evaluated in an 8-week, multicenter, open-label study. The results of this study which included a total of 54 patients showed good efficacy and safety profile for quetiapine fumarate as seen by the improvement rate (moderate or above in the final global improvement rating) of 49.1% and safety rate (no problem in overall safety rating) of 66.0%. The mean BPRS total score decreased significantly from 55.5 +/- 10.9 points at baseline to 45.4 +/- 13.0 points at the completion of administration. The PANSS scores also showed significant improvement on all scales; the mean scores decreased from 20.7 +/- 6.3 points at baseline to 17.7 +/- 6.9 points at withdrawal or completion of administration on the positive scale, from 27.8 +/- 5.8 points to 24.0 +/- 7.3 points on the negative scale, and from 51.4 +/- 10.1 points to 44.7 +/- 12.4 points on the general psychopathology scale. Although the most frequent adverse reactions were somnolence (18.9%), insomnia (17.0%), nervousness (13.2%), dizziness (13.2%), malaise (13.2%), postural hypotension (11.3%), tachycardia (9.4%), and constipation (9.4%), the incidence of extrapyramidal symptoms was low (11.3%). From these results, quetiapine fumarate was suggested to be highly effective and safe for the treatment of schizophrenia.
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187
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Kojima S, Nakamura T, Nidaira T, Nakamura K, Ooashi N, Ito E, Watase K, Tanaka K, Wada K, Kudo Y, Miyakawa H. Optical detection of synaptically induced glutamate transport in hippocampal slices. J Neurosci 1999; 19:2580-8. [PMID: 10087071 PMCID: PMC6786091] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/11/2023] Open
Abstract
Although it has long been believed that glial cells play a major role in transmitter uptake at synapses in the CNS, the relative contribution of glial and neuronal cells to reuptake of synaptically released glutamate has been unclear. Recent identification of the diverse glutamate transporter subtypes provides an opportunity to examine this issue. To monitor glutamate transporter activity, we optically detected synaptically induced changes of membrane potential from hippocampal CA1 field in slice preparations using a voltage-sensitive dye, RH155. In the presence of ionotropic glutamate-receptor blockers, synaptic inputs gave rise to a slow depolarizing response (SDR) in the dendritic field. The amplitude of SDR correlated well with presynaptic activities, suggesting that it was related to transmitter release. The SDR was found to be caused by the activities of glutamate transporters because it was not affected by blockers for GABAA, nACh, 5-HT3, P2X, or metabotropic glutamate receptors but was greatly reduced by dihydrokainate (DHK), a specific blocker for GLT-1 transporter, and by D, L-threo-beta-hydroxyaspartate (THA), a blocker for EAAC, GLAST, and GLT-1 transporters. When SDR was detected with RH482 dye, which stains both glial and neuronal cells, 1 mM DHK and 1 mM THA were equally effective in suppressing SDR. The SDR was very small in GLT-1 knockout mice but was maintained in gerbil hippocampi in which postsynaptic neurons were absent because of ischemia. Because GLT-1 transporters are exclusively expressed in astrocytes, our results provide direct evidence that astrocytes play the dominant role in sequestering synaptically released glutamate.
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188
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Uchiyama M, Okawa M, Shibui K, Kim K, Kudo Y, Hayakawa T, Kamei Y, Urata J. Poor recovery sleep after sleep deprivation in delayed sleep phase syndrome. Psychiatry Clin Neurosci 1999; 53:195-7. [PMID: 10459687 DOI: 10.1046/j.1440-1819.1999.00481.x] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
To clarify disturbances in sleep regulation in patients with delayed sleep phase syndrome (DSPS), we studied three patients with DSPS and seven healthy controls. Sleep propensity and melatonin rhythms after 24-h sleep deprivation were investigated under dim light condition by using the ultra-short sleep-wake schedule. The sleep propensity curves displayed clear differences between DSPS patients and the controls. During the subjective day when melatonin was not produced, recovery sleep after the sleep deprivation did not occur in DSPS patients, while recovery sleep occurred during the subjective day in controls. This suggests that DSPS may involve problems related to the homeostatic regulation of sleep after sleep deprivation.
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189
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Kudo Y, Uchiyama M, Okawa M, Shibui K, Kamei Y, Hayakawa T, Kim K, Ishibashi K. Correlation between the circadian sleep propensity rhythm and hormonal rhythms under ultra-short sleep-wake cycle. Psychiatry Clin Neurosci 1999; 53:253-5. [PMID: 10459703 DOI: 10.1046/j.1440-1819.1999.00536.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
The aim of this study was to clarify effects of hormonal and temperature rhythms on circadian fluctuations of sleep propensity. Ten healthy females underwent 24-h sleep deprivation and entered the circadian sleep propensity assessment setting under the ultra-short sleep-wake schedule. During the experiment, sleep propensity rhythm, rectal temperature, and 24-h serum hormone profiles (melatonin, cortisol and thyroid-stimulating hormone) were investigated. The circadian sleep propensity rhythms had two apparent peaks (afternoon and nocturnal peaks) and a trough (nocturnal sleep gate). The timings of the nocturnal sleep gate and the nocturnal peak were correlated exclusively with temperature and melatonin rhythms (P < 0.05), while that of the afternoon peak was significantly correlated with habitual wake time and melatonin rhythm. These results indicate that the circadian sleep propensity rhythm is influenced not only by the circadian pacemaker, but also by sleep habit.
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190
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Nakamura T, Minamisawa H, Katayama Y, Ueda M, Terashi A, Nakamura K, Kudo Y. Increased intracellular Ca2+ concentration in the hippocampal CA1 area during global ischemia and reperfusion in the rat: a possible cause of delayed neuronal death. Neuroscience 1999; 88:57-67. [PMID: 10051189 DOI: 10.1016/s0306-4522(98)00207-3] [Citation(s) in RCA: 48] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
The crucial role of free cytosolic Ca2+ in ischemic neuronal damage has been studied in recent years. In the present report, changes in the intracellular Ca2+ concentration in the hippocampal CA1 area during transient global ischemia and reperfusion were measured using in vivo Ca2+ fluorometry with fura-2 in the four-vessel occlusion and reperfusion model in halothane-anesthetized rats. Marked changes were seen during 10-min global ischemia, with the intracellular Ca2+ concentration increasing gradually following application of the ischemic insult and rapidly about 2 min after the beginning of ischemia, and continuing to increase until reperfusion. On reperfusion, the intracellular Ca2+ concentration began to decrease and returned to the pre-ischemic level within 15 min. Induction of severe global ischemia was confirmed by the complete suppression of synaptic activity and the decrease in hippocampal temperature in the CA1 area. After seven days, CA1 pyramidal cell loss was observed histopathologically in the same rats which had undergone measurement of the intracellular Ca2+ concentration changes. In the present study, a temporal profile of the free cytosolic Ca2+ dynamics during ischemic and early post-ischemic period was determined in vivo. The results demonstrate that the intracellular Ca2+ concentration in the hippocampal CA1 area is transiently and markedly increased during a brief ischemia-inducing delayed neuronal death, implying that Ca2+ overload during cerebral ischemia is a possible cause of the delayed cell death of CA1 pyramidal neurons.
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Ishizuka B, Kudo Y, Amemiya A, Yamada H, Matsuda T, Ogata T. Anti-nuclear antibodies in patients with premature ovarian failure. Hum Reprod 1999; 14:70-5. [PMID: 10374097 DOI: 10.1093/humrep/14.1.70] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
We examined the prevalence of anti-nuclear antibodies (ANA) in 32 consecutive patients with premature ovarian failure with and without chromosomal abnormalities. Blood samples were taken for karyotype determination as well as detection of autoantibodies, X-terminal microdeletions and spontaneous follicular growth. The correlation between ANA positivity and the age at onset of amenorrhoea, as well as the presence of karyotype abnormalities, X-terminal microdeletions and follicular growth was determined. Ten of the 24 patients with normal karyotype and none of the 8 patients with karyotype abnormalities were ANA positive. ANA were found more frequently in patients with premature ovarian failure with normal karyotypes than in control amenorrhoeic patients (42 versus 6, P < 0.01). ANA were found in 77% (10/13) of premature ovarian failure patients with normal karyotypes who developed amenorrhoea at or under the age of 30 years, but not in the patients who developed amenorrhoea later in life. Follicular growth was evident in 50% (5/10) of karyotypically normal patients with ANA, 71% (10/14) of karyotypically normal patients without ANA and 38% (3/8) of patients with karyotype abnormalities. X-terminal microdeletions were not found in any of the patients studied. These results suggest that patients with premature ovarian failure and ANA are an aetiologically and clinically distinct group.
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Kudo Y, Takata T, Yasui W, Ogawa I, Miyauchi M, Takekoshi T, Tahara E, Nikai H. Reduced expression of cyclin-dependent kinase inhibitor p27Kip1 is an indicator of malignant behavior in oral squamous cell carcinoma. Cancer 1998; 83:2447-55. [PMID: 9874448 DOI: 10.1002/(sici)1097-0142(19981215)83:12<2447::aid-cncr7>3.0.co;2-a] [Citation(s) in RCA: 42] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
BACKGROUND Reduced expression of the cyclin-dependent kinase inhibitor p27Kip1 has been reported to correlate with poor survival in cohorts of breast and colorectal carcinoma patients. Posttranslational ubiquitin-mediated proteasomal proteolysis is related to p27Kip1 protein levels. However, to the authors' knowledge, no previous study has examined the expression of p27Kip1 in oral squamous cell carcinoma (OSCC). METHODS To examine the expression of p27Kip1 and its clinicopathologic roles in OSCC, the authors studied the expression of p27Kip1 protein by immunohistochemistry in deparaffinized tissue sections of 20 normal oral mucosa specimens, 22 epithelial dysplasia specimens, and 70 OSCCs, and analyzed its correlation with clinicopathologic parameters. They also studied the expression of p27Kip1 mRNA and protein in six OSCC cell lines by Northern blot and Western blot analysis. To examine the mechanism of reduced expression of p27Kip1, OSCC cell lines were treated with the proteasome inhibitor LLnV. RESULTS All the normal oral mucosa specimens and 73% (16 of 22) of the oral epithelial dysplasia specimens expressed p27Kip1 at high levels, whereas 87% of the OSCCs (61 of 70) showed reduced expression of p27Kip1. Furthermore, the levels of expression of this protein were significantly lower in carcinomas with metastasis than those without metastasis. Although OSCC cell lines expressed p27Kip1 mRNA at various levels, most of them expressed p27Kip1 protein at lower or undetectable levels. LLnV induced the expression of p27Kip1 protein in HSC2 cells, in which p27Kip1 protein was originally undetectable. CONCLUSIONS These findings suggest that 1) reduced expression of p27Kip1 may correlate with the development and progression of OSCC and can be an indicator of malignant behavior of this neoplasm, and 2) increased proteasome-mediated degradation may play an important role in the reduction of p27Kip1 protein expression.
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Iwashita M, Sakai K, Kudo Y, Takeda Y. Phosphoisoforms of insulin-like growth factor binding protein-1 in appropriate-for-gestational-age and small-for-gestational-age fetuses. Growth Horm IGF Res 1998; 8:487-93. [PMID: 10985761 DOI: 10.1016/s1096-6374(98)80302-x] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
We analysed phosphoisoforms of insulin-like growth factor binding protein-1 (IGFBP-1) in maternal and cord sera from preterm and term fetus with different growth status. Phosphoisoforms were separated by non-SDS-polyacrylamide gel electrophoresis and detected by immunoblot. Phosphoisoforms were also analysed by anion exchange chromatography on HPLC. The proportion of non-phosphorylated IGFBP-1 to total IGFBP-1 was significantly higher in preterm fetus than in their mothers, however, the relative amounts of each IGFBP-1 isoforms were similar between preterm and term fetus. The levels of non-phosphorylated IGFBP-1 were similar between appropriate for gestational age (AGA) and small for gestational age (SGA) fetus at term, however, phosphorylated isoforms of IGFBP-1 were increased in SGA fetus compared to those of AGA fetus and the proportion of non-phosphorylated IGFBP-1 to total IGFBP-1 was lower in SGA fetus than those in AGA fetus. Thus, the profiles of non-phosphorylated and phosphorylated IGFBP-1 in the fetus varies corresponding to fetal growth suggesting that not only total amounts of IGFBP-1 but also the proportion of phosphoisoforms of IGFBP-1 is important for fetal growth.
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Hirasawa T, Nakamura T, Morita M, Ezawa I, Miyakawa H, Kudo Y. Activation of dihydropyridine sensitive Ca2+ channels in rat hippocampal neurons in culture by parathyroid hormone. Neurosci Lett 1998; 256:139-42. [PMID: 9855359 DOI: 10.1016/s0304-3940(98)00782-4] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
We examined the effects of parathyroid hormone (PTH) on rat hippocampal neurons in culture to determine whether it caused a similar intracellular calcium concentration ([Ca2+]i) increase in these cells to that seen with renal epithelial cells and found that PTH induced the effect in about 30% of the neurons. The effects appeared gradually during continuous administration of full-length PTH(1-84) or its active fragment, PTH(1-34), but not of an inactive fragment, PTH(39-84). However, the active fragment of the PTH-related peptide (PTHrP(1-34)) had little effect on [Ca2+]i during 60 min of administration. The PTH effect was inhibited by nifedipine, an L-type Ca2+ channel antagonist, and facilitated by S-(-)-BAY K 8644, an L-type Ca2+ channel agonist. Our findings suggest that PTH is one of the causal factors for the age-related increase in the density of voltage gated Ca2+ channels in hippocampal neurons.
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195
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Kojima H, Nakatsubo N, Kikuchi K, Urano Y, Higuchi T, Tanaka J, Kudo Y, Nagano T. Direct evidence of NO production in rat hippocampus and cortex using a new fluorescent indicator: DAF-2 DA. Neuroreport 1998; 9:3345-8. [PMID: 9855277 DOI: 10.1097/00001756-199810260-00001] [Citation(s) in RCA: 168] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
The biological functions of nitric oxide in the neuronal system remain controversial. Using a novel fluorescence indicator, DAF-2 DA, for direct detection of NO, we examined both acute rat brain slices and organotypic culture of brain slices to ascertain NO production sites. The fluorescence intensity in the CA1 region of the hippocampus was augmented, especially after stimulation with NMDA, in acute brain slices. This NO production in the CA1 region was also confirmed in cultured hippocampus. This is the first direct evidence of NO production in the CA1 region. There were also fluorescent cells in the cerebral cortex after stimulation with NMDA. Imaging techniques using DAF-2 DA should be very useful for the clarification of neuronal NO functions.
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Fukuchi Y, Kudo Y, Kumagai T, Ebina K, Yokota K. Oxidized low density lipoprotein inhibits the hemolytic activity of Asp-hemolysin from Aspergillus fumigatus. FEMS Microbiol Lett 1998; 167:275-80. [PMID: 9809428 DOI: 10.1111/j.1574-6968.1998.tb13239.x] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
Abstract
We have examined the effect of chemically modified human low density lipoproteins (LDLs), acetylated LDL and oxidized LDL, on the hemolytic activity of Asp-hemolysin. Oxidized LDL, but not acetylated LDL, inhibited the hemolytic activity of this toxin. The inhibitory effects of oxidized LDL increased with the time of Cu(2+)-induced LDL oxidation. Similar inhibition was observed in the filtrate which was separated from the incubation mixture of Asp-hemolysin with oxidized LDL (for 2 h of oxidation) following ultrafiltration through a membrane with a molecular mass cutoff of 100,000. However, at longer LDL oxidation times, the inhibition by the filtrates was less than the control mixture without ultrafiltration. We suggest that the inhibition by oxidized LDL was due to the binding of oxidized LDL to Asp-hemolysin at shorter LDL oxidation times.
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Hirasawa T, Kudo Y, Tokimasa T. Actions of zinc on rapidly inactivating A-type and non-inactivating M-type potassium currents in bullfrog sympathetic neurons. Neurosci Lett 1998; 255:5-8. [PMID: 9839713 DOI: 10.1016/s0304-3940(98)00683-1] [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: 10/17/2022]
Abstract
The actions of zinc on A-type potassium current (I(A)) were studied in dissociated bullfrog sympathetic neurons. Zinc (1-300 microM) caused a parallel shift in the activation and inactivation curves to a depolarizing direction, thereby enhancing I(A) around physiological resting potential. An EC50 value was 70-100 microM for these actions. The zinc actions were non-selective in a sense that zinc inhibited M-type potassium current (I(M)) with an IC50 value of 300 microM. Zinc was without effect on the maximum conductance for I(A) and the kinetic behavior for I(M). The ability of low concentrations of zinc to modulate separate set of potassium currents such as I(A) and I(M) in conceptually distinct manner may therefore assume pathophysiological importance for autonomic neurons.
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Kudo Y. [Fluorescent calcium indicators]. TANPAKUSHITSU KAKUSAN KOSO. PROTEIN, NUCLEIC ACID, ENZYME 1998; 43:1912-6. [PMID: 9788201] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/09/2023]
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199
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Kudo Y, Higashi H. [Fluorescent probes for detecting active protein kinases in the living cells]. TANPAKUSHITSU KAKUSAN KOSO. PROTEIN, NUCLEIC ACID, ENZYME 1998; 43:1922-6. [PMID: 9788203] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/09/2023]
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200
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Okuyama K, Kiuchi S, Okamoto M, Iwasaki H, Narita H, Kudo Y. Time-dependent changes in the ischemic forebrain following the microsphere-induced permanent occlusion of cerebral arterioles in rats. JAPANESE JOURNAL OF PHARMACOLOGY 1998; 78:31-7. [PMID: 9804059 DOI: 10.1254/jjp.78.31] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
To evaluate the progression of brain edema without modification by the effect of anesthetics, we examined the local and permanent ischemia model in unanesthetized rats. The forebrain embolism was induced by intra-arterial infusion of microspheres of 50-microm diameter in freely moving rats. From 2 to 48 hr following the injection, the water-, Na- and Ca-contents progressively increased while the K content decreased in the microsphere-injected hemisphere. After the 3rd day, the water- and Na-contents gradually decreased and returned to the normal level on the 14th day. In contrast, the Ca level remained elevated even on the 56th day. The animals showed signs of neurological deficits 24 hr after the injection. In histopathological examination, large infarct areas were present in the microsphere-injected hemisphere after 24 to 48 hr. One to two weeks later, the lateral ventricle was expanded. Eight weeks after the injection, the ventricle remained expanded and newly developed infarct areas were observed in a scattered pattern around the fibrotic area. The results show the close correlation between the development of edema and the increase/decrease of Na/K contents from the onset to the recovery from edema, and their changes are similar to those in human stroke. This model enables us to evaluate not only the acute ischemic insult but also the chronic changes of the forebrain following the stroke.
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