1701
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Shimizu T. Role of the cytoskeleton in the generation of spatial patterns in Tubifex eggs. Curr Top Dev Biol 1996; 31:197-235. [PMID: 8746666 DOI: 10.1016/s0070-2153(08)60228-8] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
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1702
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Sato S, Kume K, Takan T, Mutoh H, Taketani Y, Shimizu T. Up-regulation of the intracellular Ca2+ signaling and mRNA expression of platelet-activating factor receptor by estradiol in human uterine endometrial cells. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 1996; 416:95-100. [PMID: 9131133 DOI: 10.1007/978-1-4899-0179-8_17] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Platelet-activating factor (PAF, 1-O-alkyl-2-acetyl-sn-glycero-3-phosphocholine), a potent chemical mediator in inflammation, plays a role in reproduction. Using primary culture of human uterine endometrial cells, we investigated the effect of sex steroid hormones on the PAF-induced signal and its receptor mRNA expression. After a 24 hr treatment with estradiol, PAF increased the intracellular calcium ion ([Ca2+]i) in the glandular cells, but not in the stromal cells. This response was not observed in the non-treated cells, and was blocked by a PAF antagonist, WEB2086. Two types of mRNA (transcript 1 and transcript 2) occurred for PAF receptor by alternative splicing, which are under control of two distinct promoters. Using RT-PCR analysis, it was shown that both transcripts existed in endometrial cells and that estradiol alone or a combination of estradiol and progesterone induced the accumulation of transcript 2, the promoter of which responded to estrogen in our previous studies. The regulation of PAF receptor by sex steroid hormones in human uterine endometrial cells suggests that PAF is involved in the physiological process of reproduction.
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1703
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Nakamura M, Sakanaka C, Aoki Y, Ogasawara H, Tsuji T, Kodama H, Matsumoto T, Shimizu T, Noma M. Identification of two isoforms of mouse neuropeptide Y-Y1 receptor generated by alternative splicing. Isolation, genomic structure, and functional expression of the receptors. J Biol Chem 1995; 270:30102-10. [PMID: 8530415 DOI: 10.1074/jbc.270.50.30102] [Citation(s) in RCA: 77] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
Two cDNA clones homologous with human neuropeptide (NP) Y-Y1 receptor have been isolated from a mouse bone marrow cDNA library. One was thought to be the cognate of the human NPY-Y1 receptor, termed Y1 alpha receptor, and the other form, termed Y1 beta receptor, differed from the Y1 alpha receptor in the seventh transmembrane domain and C-terminal tail. Analysis of the mouse genomic DNA showed that both receptors originated from a single gene. The different peptide sequences of the Y1 beta receptor were encoded by separate exons, hence, these receptors were generated by differential RNA splicing. High affinity binding of [125I]NPY to each receptor expressed in Chinese hamster ovary (CHO) cells and sequestration of [125I]NPY after binding to each receptor were observed. In the CHO cells expressing the Y1 alpha receptor, intracellular Ca2+ increase, inhibition of forskolin-induced cAMP accumulation, and mitogen-activated protein kinase (MAPK) activation were observed by stimulation of NPY, and these responses were abolished by pretreatment with pertussis toxin. Since wortmannin completely inhibited NPY-elicited MAPK activation, we speculate that wortmannin-sensitive signaling molecule(s) such as phosphoinositide 3-kinase may lie between pertussis toxin-sensitive G-protein and MAPK. In contrast, these intracellular signals were not detected in CHO cells expressing the Y1 beta receptor. Northern blots and reverse transcriptase-polymerase chain reaction analyses indicated that the Y1 alpha receptor was highly expressed in the brain, heart, kidney, spleen, skeletal muscle, and lung, whereas the Y1 beta receptor mRNA was not detected in these tissues. However, the Y1 beta receptor was expressed in mouse embryonic developmental stage (7 and 11 days), bone marrow cells and several hematopoietic cell lines. These results suggest that the Y1 beta receptor is an embryonic and a bone marrow form of the NPY-Y1 receptor, which decreases in the expression during development and differentiation.
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1704
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Goto M, Shimizu T, Sawada J, Sawa C, Watanabe H, Ichikawa H, Ohira M, Ohki M, Handa H. Assignment of the E4TF1-60 gene to human chromosome 21q21.2-q21.3. Gene X 1995; 166:337-8. [PMID: 8543189 DOI: 10.1016/0378-1119(95)00575-7] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
The gene encoding human transcription factor E4TF1-60 was previously mapped to chromosome 21q21. We analyzed the localization of the E4TF1-60 gene in more detail by genomic Southern hybridization and determined the sequence of the exons and the regions surrounding the intron boundaries. We report here that E4TF1-60 locates in the long arm of chromosome 21 at q21.2-q21.3 and contains a total of ten exons.
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1705
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Izumi T, Shimizu T. Platelet-activating factor receptor: gene expression and signal transduction. BIOCHIMICA ET BIOPHYSICA ACTA 1995; 1259:317-33. [PMID: 8541341 DOI: 10.1016/0005-2760(95)00171-9] [Citation(s) in RCA: 185] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
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1706
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Borlongan CV, Shytle RD, Ross SD, Shimizu T, Freeman TB, Cahill DW, Sanberg PR. (-)-nicotine protects against systemic kainic acid-induced excitotoxic effects. Exp Neurol 1995; 136:261-5. [PMID: 7498416 DOI: 10.1006/exnr.1995.1103] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
(-)-Nicotine was shown to produce in vivo protection against neurobehavioral effects caused by systemically administered kainic acid (KA), an excitotoxin that has been widely used to induce temporal lobe convulsions including "wet dog shakes" in experimental animals. Rats pretreated with (-)-nicotine (0.5 mg/kg sc) 15 min before receiving KA (12.0 mg/kg sc) exhibited a marked reduction (P < 0.5) in the number of wet dog shakes when compared to saline-pretreated rats. Similarly, little visible brain damage was found in the (-)-nicotine-pretreated rats, but a widespread reduction in acetylcholinesterase-positive neurons was noted in the hippocampal areas of the saline-pretreated animals. While the mechanism of neuroprotection of (-)-nicotine is still not known, these findings suggest that (-)-nicotine may act as a therapeutic agent for putative excitotoxin-mediated disorders.
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1707
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Kojima K, Suginami H, Egawa H, Uda S, Horie K, Tokushige M, Shimizu T. [Recurrent inversion of the puerperal uterus managed with the Ocejo operation]. NIHON SANKA FUJINKA GAKKAI ZASSHI 1995; 47:1375-7. [PMID: 8568358] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
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1708
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Masuko Y, Tazawa K, Viroonchatapan E, Takemori S, Shimizu T, Fujimaki M, Nagae H, Sato H, Horikoshi I. Possibility of thermosensitive magnetoliposomes as a new agent for electromagnetic induced hyperthermia. Biol Pharm Bull 1995; 18:1802-4. [PMID: 8787814 DOI: 10.1248/bpb.18.1802] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
This study examined a possibility of dextran magnetite (DM)-incorporated thermosensitive liposomes, namely thermosensitive magnetoliposomes (TMs), as a new hyperthermic agent. The temperatures of TM suspensions and cancer tumors injected with TM suspensions were efficiently elevated up to 42 degrees C by electromagnetic induced heating at a frequency of 500 kHz under both in vitro and in vivo conditions. Thus, a possibility of TMs for selective hyperthermia was demonstrated. The temperature rises obtained at various concentrations of TMs suggest that approximately 15 mg Fe/cm3 tumor volume is adequate as a therapeutic dose of TMs for efficient selective hyperthermia.
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1709
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Matsumura K, Shimizu T. [Severe childhood autosomal recessive muscular dystrophy]. Rinsho Shinkeigaku 1995; 35:1422-4. [PMID: 8752417] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Dystrophin is associated with several novel sarcolemmal proteins via the cysteine-rich/C-terminal domains. The dystrophin-associated proteins are classified into three groups: (1) alpha- and beta-dystroglycan, (2) adhalin, 35DAG and A3b, and (3) members of the syntrophin family. Dystrophin interacts with F-actin via the N-terminal domain. Alpha-dystroglycan binds laminin-2, a major component of the basal lamina. These findings indicate that the dystrophin-glycoprotein complex (DGC) links the subsarcolemmal cytoskeleton with the basal lamina, thus providing mechanical stability to the sarcolemmal. The DGC may also play a role in signal transduction. We have reported previously the deficiency of adhalin in skeletal muscle of Arab patients afflicted with severe childhood autosomal recessive muscular dystrophy (SCARMD). SCARMD is now known to affect other races including Europeans and Japanese. Although the phenotype of this disease can mimic Duchenne muscular dystrophy in severe cases, it is sometimes quite mild. SCARMD is genetically heterogeneous. Recently, adhalin gene mutations have been demonstrated in European, Arab and Japanese families with SCARMD. Another locus is on chromosome 13q, however, the mutated gene remains elusive. In the advanced stages of SCARMD, the expression of laminin is disturbed, suggesting that adhalin deficiency may cause the dysfunction of the DGC as a laminin receptor, which may eventually lead to muscle cell death.
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1710
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Kitano M, Shimizu T, Yamazaki Y, Umezu Y, Arakawa Y, Daimon Y. Serum insulin-like growth factor-I (IGF-I) in normal Japanese adults. Endocr J 1995; 42:767-70. [PMID: 8822318 DOI: 10.1507/endocrj.42.767] [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: 02/02/2023] Open
Abstract
To evaluate surgical and medical treatment of GH-producing pituitary tumors and GH supplement to GH-deficient patients, we determined the reference values for serum IGF-I in Japanese adults. The serum IGF-I concentration in 454 apparently healthy subjects (246 men aged 21-70 years and 208 women aged 21-72 years) was measured with a commercial RIA kit after acid-ethanol extraction. The concentration of serum IGF-I decreased with age in both sexes. The IGF-I in females was significantly higher than that in males in the group aged 21-30 years and lower in the group aged 61-72 years. We conclude that an age- or sex-related standard is necessary for comparing IGF-I values in patients.
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1711
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Matsumine H, Shimizu T, Sato K, Mizuno Y. [Anosognosia, 2)anosodiaphoria]. NO TO SHINKEI = BRAIN AND NERVE 1995; 47:1196-7. [PMID: 8534558] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
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1712
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Hayasaka S, Kinuwaki E, Nakabayashi T, Saito R, Komatsu H, Nishikawa H, Ohizumi K, Shimizu T, Nakai Y, Niitani H. [Early phase II study of oral administration of etoposide for 21 consecutive days in patients with non-small-cell lung cancer]. NIHON KYOBU SHIKKAN GAKKAI ZASSHI 1995; 33:1367-1371. [PMID: 8821989] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
An early phase II clinical study was done to investigate the activity and the safety of oral administration of etoposide for 21 consecutive days in patients with non-small-cell lung cancer. An interim analysis was done after registration of 24 cases. One case was a dropout because of an insufficient administration period (4 days). The other 23 cases were complete: they comprised 9 cases of adenocarcinoma, 13 cases of squamous cell carcinoma, and 1 case of large cell carcinoma. Prior therapy had not been given in two cases. The doses used were 50 mg/person/day in 12 cases and 75 mg/person/day in 11 cases. The response observed was one case of at 50 mg/person/day to stage IV squamous cell carcinoma, 17 cases were no change, 5 cases were progressing disease, and giving a response rate of 4.3% in complete cases. Considering those results, we decided that it would be difficult to achieve a 20% response rate by the end of this study, and therefore the study was terminated. The side effects of the regimen were tolerable. In conclusion, etoposide was not active against non-small-cell lung cancer at the dosage and schedule employed. Further investigation is required to obtain a more effective form of therapy.
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1713
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Shimizu T, Kitano T, Inoue M, Narikawa K, Fujii B. Ten-year longitudinal clinical evaluation of a visible light cured posterior composite resin. Dent Mater J 1995; 14:120-34. [PMID: 8940551 DOI: 10.4012/dmj.14.120] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Using modified USPHS criteria, we evaluated annually for ten years 91 cases restored with visible light cured posterior composite resin LFP (Base resin: UDMA; filler: micro crushed type, alumino-silicate, barium glass and silica, 85 wt%, 74 vol%). The 91 cases restored with LFP decreased to 68 in ten years. Of the 23 cases that were lost, one resulted from a pulpal reaction immediately following restoration, four were extracted owing to periodontal disease or extrusion of third molars, two became abutments owing to loss of an adjacent tooth, eight had recurrent caries, and eight were lost owing to caries on a surface having no relationship to the composite resin restoration. Because we observed comparatively little wear, good marginal adaptability, and no discoloration, we concluded that the ten-year clinical success of LFP was on the whole very good, and that this resin has adequate clinical merit as a restorative material for posterior teeth when restricted to restorations covering comparatively small areas.
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1714
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Shimizu T, Iijima M, Tanaka Y. [Radiotherapy for intracranial meningioma: special reference to malignant and high risk benign meningioma]. NIHON IGAKU HOSHASEN GAKKAI ZASSHI. NIPPON ACTA RADIOLOGICA 1995; 55:1047-52. [PMID: 8587846] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Results of radiotherapy in 21 patients who had been treated for intracranial meningioma from April 1975 to March 1993 at Tokyo Metropolitan Komagome Hospital are presented. All patients were treated with 4 MV X-rays using conventional fractionation. The median tumor dose was 54.4 Gy (range 30 Gy to 70 Gy). Radiotherapy was delivered by conformation technique in 11, parallel opposed field in four and three ports technique in two. Of 21 meningiomas, 13 were histologically malignant and 8 were benign. The median follow-up period was 63 months. Overall survival rate at 5 years was 71% for benign and 63% for malignant meningiomas; the 5-year progression-free survival rates were 25% and 30%, respectively. Eight of 21 patients received 60 Gy or more, and the remaining 13 received less than 60 Gy. The 5-year overall survival rates for these two groups were 43% and 83% (p < 0.05), respectively. Ten of 21 patients were treated with post-operative radiotherapy as initial treatment and eleven of 21 patients were treated with salvage therapy with or without surgical excision for recurrent lesions. The 5-year survival rates and progression-free survival rates of these two groups showed no significant differences. From analysis of the clinical course of the salvage therapy group, radiotherapy may prolong survival time and delay further tumor recurrence. According to the present study, radiotherapy (doses of 55 Gy to 60 Gy) after primary resection and at the time of recurrence are equally effective for prolongation of survival and delay of further tumor recurrence.
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1715
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Shimizu T, Hiraoka M, Nakanomyo H. Enantioselective determination of sotalol enantiomers in biological fluids using high-performance liquid chromatography. JOURNAL OF CHROMATOGRAPHY. B, BIOMEDICAL APPLICATIONS 1995; 674:77-83. [PMID: 8749254 DOI: 10.1016/0378-4347(95)00304-5] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
A simple and sensitive high-performance liquid chromatographic (HPLC) method for the determination of (+)-(S)-sotalol and (-)-(R)-sotalol in biological fluids was established. Following extraction with isopropyl alcohol from biological samples on a Sep-Pak C18 cartridge, the eluent was derivatized with 2,3,4,6-tetra-O-acetyl-beta-D-glucopyranosyl isothiocyanate (GITC). The diastereoisomeric derivates were resolved by HPLC with UV detection at 225 nm. Calibration was linear from 0.022 to 4.41 micrograms/ml in human plasma and from 0.22 to 88.2 micrograms/ml in human urine for both (+)-(S)- and (-)-(R)-sotalol. The lower limit of determination was 0.022 microgram/ml for plasma and 0.22 microgram/ml for urine. The within-day and day-to-day coefficients of variation were less than 7.5% for each enantiomer at 0.09 and 1.8 microgram/ml in plasma and at 0.44 and 4.4 micrograms/ml in urine. The method is also applicable to other biological specimens such as rat, mouse and rabbit plasma.
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1716
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Iwamoto Y, Suzuki Y, Kurita A, Watanabe Y, Shimizu T, Ohgami H, Yanagihara Y. Rapid and sensitive PCR detection of Vibrio trachuri pathogenic to Japanese horse mackerel (Trachurus japonicus). Microbiol Immunol 1995; 39:1003-6. [PMID: 8789060 DOI: 10.1111/j.1348-0421.1995.tb03290.x] [Citation(s) in RCA: 4] [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
A polymerase chain reaction (PCR) method was performed for rapid and sensitive detection of pathogenic Vibrio trachuri isolated from cultured Japanese horse mackerel. A set of primers was selected from the base sequence of the Pst I fragment of T9210 chromosomal DNA and used for PCR detection of T9210. This PCR specifically amplified the DNAs from V. trachuri T9210, T9213, and T9216 but not of those other bacterial strains. PCR using a Pst I-1 primer set made it possible to detect 100 fg of T9210 DNA. The PCR method reported here may be useful for detection and identification of V. trachuri pathogenic to Japanese horse mackerel.
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1717
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Shimizu T, Sekiya T. Loss of heterozygosity at 9p21 loci and mutations of the MTS1 and MTS2 genes in human lung cancers. Int J Cancer 1995; 63:616-20. [PMID: 7591275 DOI: 10.1002/ijc.2910630503] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
To elucidate the involvement of abnormalities of the MTS1/p16 and MTS2/p15 genes located at chromosomal region 9p21 in human lung cancers, we analyzed DNA from 30 primary lung cancers and detected loss of heterozygosity at the 9p21-p23 region in 15 tumors. Single-strand-conformation-polymorphism analysis of polymerase-chain-reaction products from the MTS1 and MTS2 genes and determination of the nucleotide sequences revealed the presence of a mutated MTS1 gene in 2 of 15 tumors with a loss of corresponding loci. No mutations of the MTS2 gene were found. These results suggested that mutations of the MTS1 gene are associated with at least some human lung cancers.
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1718
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Yamada H, Hori H, Tanaka T, Fujita S, Fukuta-Ohi H, Hojo S, Tamura A, Shimizu T, Matsumura K. Secretion of laminin alpha 2 chain in cerebrospinal fluid. FEBS Lett 1995; 376:37-40. [PMID: 8521961 DOI: 10.1016/0014-5793(95)01240-3] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
The absence of laminin alpha 2 chain causes muscle cell degeneration and peripheral dysmyelination in congenital muscular dystrophy patients and dy mice, suggesting its role in the maintenance of sarcolemmal architecture and peripheral myelinogenesis. Here we demonstrate the secretion of laminin alpha 2 chain in cerebrospinal fluid (CSF). Laminin alpha 2 chain was detected as a minor component of the total CSF proteins or glycoproteins. Laminin alpha 2 chain was localized in the cytoplasm of epithelial cells of choroid plexus, suggesting active secretion. Our results suggest that immunochemical analysis of CSF laminin alpha 2 chain could be useful as an aid for the diagnosis of congenital muscular dystrophy.
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1719
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Woodson W, Shimizu T, Wild JM, Schimke J, Cox K, Karten HJ. Centrifugal projections upon the retina: an anterograde tracing study in the pigeon (Columba livia). J Comp Neurol 1995; 362:489-509. [PMID: 8636463 DOI: 10.1002/cne.903620405] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
Previous work has shown that the avian retina receives two types of centrifugal fibers from the brain. These types can be distinguished based on the size and the morphology of their terminal endings and have been termed convergent and divergent. The centrifugal fibers arise from the isthmooptic nucleus (ION) and the surrounding ectopic cell region (ECR). We used injections of anterograde tracers either to the ION/ECR or to the ECR only to determine the morphology, depth of termination, and regional distribution of the centrifugal fibers arising from each. We found that the ECR gives rise only to the divergent type of the centrifugal fiber, whereas the ION gives rise mainly to the convergent type but may also send some fibers of the divergent type. Most of the fibers project contralaterally, although a few from the ECR project ipsilaterally. The terminals of either type are not uniformly distributed throughout the retina; instead, they are found mainly in the inferior, midtemporal, to nasal portion of the retina and appear to avoid the fovea and most of the red field. By comparison, the ION receives a major projection from portions of the tectum that receive input from the fovea and the red field in a type of neural loop. The neural loop does not project to the same point (homotopic), but projects from the red field to the inferior retina (heterotopic), as was recently proposed by Holden (1990; Vis. Neurosci. 4:493-497). The distribution of centrifugal axons corresponds to displaced ganglion cells that selectively innervate the nuclei of the accessory optic system (AOS), including the nucleus of the basal optic root (dorsal, ventral, and lateral) and the nucleus lentiformis mesencephali, pars magnocellularis. We suggest that the centrifugal axons act by increasing the gain on the AOS, thereby enhancing retinal stabilization of gaze with improved accuracy of pecking of small objects.
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1720
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Zhang Z, Fukunaga K, Shimizu T, Nakao K. Synthesis of model glycolipids having two long alkyl chains. Carbohydr Res 1995; 277:C1-C3. [PMID: 8556731 DOI: 10.1016/0008-6215(95)00298-8] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
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1721
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Murphy S, Shimizu T, Miripol J. Platelet storage for transfusion in synthetic media: further optimization of ingredients and definition of their roles. Blood 1995; 86:3951-60. [PMID: 7579366] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
Currently, most platelet concentrates (PC) are stored for transfusion at 20 degrees C to 24 degrees C in autologous plasma. There are potential advantages in replacing some of this plasma with a synthetic medium. In this study, our major goals were to define the optimal ingredients and their concentrations in such a medium and to gain insight into the mechanism by which each ingredient confers benefit. In addition, we wished to validate a new polyvinyl chloride container plasticized with di-n-decyl phthalate (DnDP) for PC storage. PC derived from donations of whole blood were stored for 7 days in autologous plasma or a basic synthetic medium (BSM) containing 15 mmol/L glucose, 21 mmol/L citrate, and physiologic concentrations of salts other than bicarbonate within either the DnDP container or a licensed polyolefin container, PL-732. Metabolic events were characterized and a panel of in vitro tests were used to monitor platelet quality as systematic changes in the BSM were made. Platelet quality was as least as good, if not better, after storage in DnDP in comparison to PL-732. pH consistently decreased to less than 6.0 because of inadequate buffering of lactic acid in BSM alone. However, pH and the in vitro tests were well maintained by either the serial addition of bicarbonate (BSM + B) or the addition of at least 15 mmol/L acetate and 10 mmol/L phosphate (BSM + AP). The benefits of BSM + AP were traced to a decrease in lactic acid production by 33% and 19% relative to plasma and BSM + B, respectively, and the vigorous oxidation of acetate (0.66 +/- 0.09 mmol/d/10(12 platelets). The rates of lactate production and acetate consumption were similar and the pH during storage correlated with difference between the two rates, suggesting that acetate oxidation has an alkalinizing effect equivalent on a molar basis to the acidifying effect of production of lactate and a hydrogen ion. When pyruvate replaced acetate, it was also metabolized vigorously (0.52 +/- 0.06 mmol/d/10(12) platelets). Its presence suppressed lactic acid production by 44% relative to BSM + B and allowed maintenance of pH and platelet quality similar to what is achieved with acetate. The results strongly suggest that the benefit from acetate (or pyruvate) is derived from its oxidation and the use of a hydrogen ion during that oxidation. For reasons that are not yet clear, the omission of phosphate resulted in pH decrease to less than 6.0 in 3 of 9 PC even with acetate present.(ABSTRACT TRUNCATED AT 400 WORDS)
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1722
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Tanigawara Y, Komada F, Shimizu T, Iwakawa S, Iwai T, Maekawa H, Hori R, Okumura K. Population pharmacokinetics of theophylline. III. Premarketing study for a once-daily administered preparation. Biol Pharm Bull 1995; 18:1590-8. [PMID: 8593486 DOI: 10.1248/bpb.18.1590] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
The population pharmacokinetic parameters for a once-daily administered preparation, Uniphyl were estimated from data collected in the premarketing clinical trial. Altogether, 2772 serum theophylline concentrations were obtained from 131 normal subjects and 306 patients suffering from chronic asthma or chronic obstructive pulmonary disease who participated in the phase I, II, and III clinical trials in Japan. The serum concentration profile was described by a linear one-compartment model with first-order absorption. The factors affecting the pharmacokinetics of this drug were examined by the likelihood ratio test using a nonlinear mixed effect model (NONMEM). The first-order absorption rate constant (Ka) for a 200-mg tablet in a fasting condition was obtained as 0.0773 (1/h), which was smaller than the elimination rate constant (0.168 1/h), indicating the flip-flop characteristic of this preparation. Food indigestion increased the Ka by 17% and the absorption lag time by 5-fold but did not affect the extent of absorption. The 400-mg tablet showed a Ka value 19%, smaller than the 200-mg tablet. Children not older than 15 years showed 58% longer absorption lag time. The inter-individual variability in Ka was 19%, suggesting small variability in the vivo release process. The total body clearance was related to hepatic function, smoking habits, and age. Furthermore, clearance decreased in association with the severity of illness. The findings obtained here are useful not only for the initial dosage adjustment for patients with a variety of backgrounds but also for doses individualization based on serum concentration monitoring with or without the Bayesian feedback method.
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1723
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Kobayashi T, Shimizu T, Hayashi H. Transcriptional analysis of the beta-galactosidase gene (pbg) in Clostridium perfringens. FEMS Microbiol Lett 1995; 133:65-9. [PMID: 8566714 DOI: 10.1111/j.1574-6968.1995.tb07862.x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
The mode of expression of the beta-galactosidase gene (pbg) of Clostridium perfringens was examined. The pbg gene was transcribed on a single 3.7-kb mRNA. The transcript contained a message for ORF54, located upstream of the pbg gene in the chromosome, indicating that ORF54 and the pbg gene comprise one operon (pbg operon). Expression of the pbg operon was induced by lactose at the transcriptional level. The promoter structure of the pbg operon was characterized by many palindrome structures and direct repeats, which suggests that there might be some catabolite regulation of the expression of the pbg operon in C. perfringens.
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1724
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Shimizu T, Yamashiro Y, Igarashi J, Yabuta K. Inhibitory effects of azelastine and tranilast on leukotriene B4 and leukotriene C4 generation by rat colonic mucosa. Prostaglandins Leukot Essent Fatty Acids 1995; 53:355-8. [PMID: 8596775 DOI: 10.1016/0952-3278(95)90056-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Anti-allergic drugs such as sodium cromoglycate are known to be effective for the treatment of ulcerative colitis (UC). Because leukotriene (LT) production is considered to play an important role in the pathophysiology of UC, we examined the effect of the anti-allergic drugs, azelastine and tranilast, and the 5-lipoxygenase inhibitor, AA861, on LTB4 and LTC4 production by isolated rat colonic mucosa treated with the calcium ionophore, A23187. Preincubation of colonic mucosa with AA861 (10(-4) M) or azelastine (10(-4) M) significantly reduced AA23187-induced LTB4 (p < 0.01 and p < 0.05, respectively) and LTC4 (p < 0.01) production. Pretreatment with tranilast (10(-3) M) also significantly reduced A23187-induced LTC4 production (p < 0.05). These findings suggest that azelastine and tranilast can inhibit LT production in colonic mucosa and may be beneficial in the treatment of patients with UC.
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1725
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Shimizu T, Beijer E, Strandvik B. Leukotriene B4 and C4 metabolism in small intestine mucosa of children with celiac disease. J Pediatr Gastroenterol Nutr 1995; 21:426-9. [PMID: 8583294 DOI: 10.1097/00005176-199511000-00009] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
The enhanced generation of eicosanoids, including leukotrienes (LTs), may be involved in the pathophysiology of small intestine mucosal injury in patients with celiac disease. We investigated the metabolism of LTB4 and LTC4 by small intestine mucosa in patients with celiac disease by incubating biopsies of small intestine mucosa from patients and healthy subjects in media containing LTB4 and LTC4 and measuring the changes in LTB4 and cysteinyl LT concentrations in the incubation media. There was no significant degradation of LTB4 during a 60-min incubation of the small intestine mucosa from either children with celiac disease or controls. LTC4 was metabolized to LTD4 and LTE4 in a time-dependent manner by the small intestine mucosa of both patients and controls. However, the decreases in LTC4 and the increases in LTD4 and LTE4 by the intestinal mucosa from patients with celiac disease occurred more slowly than the changes observed in control experiments. Reduced catabolism of LTC4 in the small intestine mucosa due to villous atrophy may contribute to increased levels of LTC4 and may play an important role in the pathophysiology of celiac disease.
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