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Takemura A, Suzuki A, Kitazume T, Sonobe T, Tsuchiya K, Korenaga T. [The utility of coronary magnetic resonance angiography in children under six years of age with Kawasaki disease]. Nihon Hoshasen Gijutsu Gakkai Zasshi 2008; 64:874-876. [PMID: 18719305 DOI: 10.6009/jjrt.64.874] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
BACKGROUND To follow up coronary arterial lesions due to Kawasaki disease (KD) using noninvasive magnetic resonance coronary angiography (MRCA), we studied a method to improve the quality of images in young children. METHOD Non-contrast enhanced, free-breathing MRCA with the vector ECG gating real-time navigator-echo 3D steady-state free precession (SSFP) technique was performed using a 1.5-T whole-body MR imaging system (Philips) in 68 children with KD aged 4 months to less than 6 years. A flex medium coil was used. Data were acquired with a 180 to 200 mm field of view (FOV) and were reconstructed with a 512 x 360 matrix. Patients were sedated during the examination. Many parameters were optimized for each patient; i.e., FOV, acquisition delay, turbo-field echo-factor, navigator-window and resolution, which resulted in the acquisition of high-resolution and high-signal images of the coronary arteries. RESULTS These conditions remarkably improved not only the quality of the images, but also the detection rate of coronary arterial segments (American Heart Association) in the children. The rates were as follows; Segments 1 (97%), 2 (97%), 3 (87%), 4 (66%), 5 (97%), 6 (96%), 7 (83%), 8 (56%), 9 (53%), 10 (21%), 11 (96%), 12 (29%), 13 (93%), 14 (54%), and 15 (65%). CONCLUSION MRCA is a useful method for evaluation coronary aneurysms from the early stages of KD, even in infants and small children.
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Affiliation(s)
- A Takemura
- Department of Radiology, Tokyo Teishin Hospital, Japan
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Yamazaki T, Ichige T, Takei S, Kawashita S, Kitazume T, Kubota T. Effect of allylic CH(3-n)F(n) groups (n = 1-3) on pi-facial diastereoselection. Org Lett 2001; 3:2915-8. [PMID: 11529789 DOI: 10.1021/ol016401g] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
[structure: see text]. Michael addition of various enolates toward gamma-CH(3-n)F(n)-alpha,beta-unsaturated ketones (n = 1-3) was proven to smoothly furnish the 1,4-adducts with high si face selectivities which monotonously decreased by reduction in the number of fluorines. Although the Felkin-Anh model correctly anticipates the present stereochemical outcome only with E-acceptors, the hyperconjugative stabilization of transition states by electron donation from the allylic substituents (the Cieplak rule) successfully explains the pi-facial preference of both acceptors at least in a qualitative level.
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Affiliation(s)
- T Yamazaki
- Department of Bioengineering, Tokyo Institute of Technology, 4259 Nagatsuta-cho, Midori-ku, Yokohama 226-8501, Japan.
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Zhang L, Takaya N, Kitazume T, Kondo T, Shoun H. Purification and cDNA cloning of nitric oxide reductase cytochrome P450nor (CYP55A4) from Trichosporon cutaneum. Eur J Biochem 2001; 268:3198-204. [PMID: 11389721 DOI: 10.1046/j.1432-1327.2001.02206.x] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Cytochrome P450nor is involved in fungal denitrification as nitric oxide (NO) reductase. Although the heme protein has been known to occur in restricted species of fungi that belong to ascomycotina, we have previously suggested that it would also occur in the yeast Trichosporon cutaneum, which is phylogenetically far from those P450nor-producing ascomycetous fungi. Here we isolated and characterized the heme protein from the basidiomycetous yeast T. cutaneum. P450nor of the yeast (TcP450nor) exhibited properties in terms of catalysis, absorption spectrum and molecular mass that are almost identical to those of its counterparts in ascomycetous fungi. We also isolated and sequenced its cDNA. The predicted primary structure of TcP450nor showed high sequence identities (around 65%) to those of other P450nors, indicating that they belong to the same family. TcP450nor protein cofractionated with cytochrome c oxidase by subcellular fractionation and its predicted primary structure contained an extension on its amino terminus that is characteristic of a mitochondrial-targeting signal, indicating that it is a mitochondrial protein like some of the isoforms of other fungi. On the other hand, TcP450nor was unique in that inducers such as nitrate, nitrite, or NO were not required for its production in the cells. The occurrence of P450nor across the subdivisions of eumycota suggests that P450nor and denitrification are distributed more universally among fungi than was previously thought.
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Affiliation(s)
- L Zhang
- Institute of Applied Biochemistry, University of Tsukuba, Ibaraki, Japan
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Kobayashi Y, Kumar GB, Kurachi T, Acharya HP, Yamazaki T, Kitazume T. Furan ring oxidation strategy for the synthesis of macrosphelides A and B. J Org Chem 2001; 66:2011-8. [PMID: 11300894 DOI: 10.1021/jo001495d] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
By using the convenient protocol for conversion of 2-substituted furans into 4-oxo-2-alkenoic acids ((i) NBS, (ii) NaClO(2)), macrosphelide B (2) was synthesized from furyl alcohol 5 (>98% ee) and acid 6 (99% ee). The protocol was first applied to the PMB ether of 5 to afford acid 13b. On the other hand, DCC condensation of acid 6 with 5 gave 16 after deprotection of the TBS group. Condensation was again carried out between 13b and 16 to furnish the key ketone 17, which upon reduction with Zn(BH(4))(2) afforded anti alcohol 18 stereoselectively (15:1). After protection/deprotection steps, the furan 18 was converted to seco acid 3 by using the furan oxidation protocol mentioned above, and lactonization of 3 with Cl(3)C(6)H(2)COCl, Et(3)N, and DMAP afforded 22 (MOM ether of 2), which upon deprotection with TFA produced 2. Transformation of 22 to macrosphelide A (1) was then investigated. Although the chelation-controlled reduction of 22 should afford the desired anti alcohol 24, Zn(BH(4))(2) at <-90 degrees C gave a 2 approximately 1:1 mixture of anti/syn alcohols. On the contrary, reduction with NaBH(4) in MeOH at -15 degrees C produced the syn isomer 23 with >10:1 diastereoselectivity. Mitsunobu inversion of the resulting C(14)-hydroxyl group and deprotection of the MOM group with TFA afforded 1. Similarly, reduction of 2 with NaBH(4) afforded the C(14)-epimer of 1 stereoselectively. The observed stereoselectivity in the reductions of 22 and 2 could be explained on the basis of computer-assisted calculation, which showed presence of the low-energy conformers responsible for the stereoselective reduction. In addition, conversion of 2 to 1 was established, for the first time.
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Affiliation(s)
- Y Kobayashi
- Department of Biomolecular Engineering, Tokyo Institute of Technology, 4259 Nagatsuta-cho, Midori-ku, Yokohama 226-8501, Japan
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Yamazaki T, Hiraoka S, Sakamoto J, Kitazume T. Mesyloxy-group migration as the stereoselective preparation method of various functionalized olefins and its reaction mechanism. Org Lett 2001; 3:743-6. [PMID: 11259051 DOI: 10.1021/ol007060u] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
[structure: see text]. It was demonstrated that mesylation of appropriate gamma,gamma-difluorinated allylic alcohols under usual conditions furnished the corresponding alpha,alpha-difluorinated allylic mesylates, possibly by way of 1,3-mesyloxy-group migration after formation of the expected "normal" intermediates, gamma,gamma-difluorinated allylic mesylates. This rearrangement was conveniently applied to the construction of trisubstituted allylic alcohols, alpha,beta-unsaturated esters, amides, or ketones in good to excellent chemical yields with exclusive E selectivities.
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Affiliation(s)
- T Yamazaki
- Department of Bioengineering, Tokyo Institute of Technology, 4259 Nagatsuta-cho, Midori-ku, Yokohama 226-8501, Japan.
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Kitazume T, Takaya N, Nakayama N, Shoun H. Fusarium oxysporum fatty-acid subterminal hydroxylase (CYP505) is a membrane-bound eukaryotic counterpart of Bacillus megaterium cytochrome P450BM3. J Biol Chem 2000; 275:39734-40. [PMID: 10995755 DOI: 10.1074/jbc.m005617200] [Citation(s) in RCA: 62] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The gene of a fatty-acid hydroxylase of the fungus Fusarium oxysporum (P450foxy) was cloned and expressed in yeast. The putative primary structure revealed the close relationship of P450foxy to the bacterial cytochrome P450BM3, a fused protein of cytochrome P450 and its reductase from Bacillus megaterium. The amino acid sequence identities of the P450 and P450 reductase domains of P450foxy were highest (40.6 and 35.3%, respectively) to the corresponding domains of P450BM3. Recombinant P450foxy expressed in yeast was catalytically and spectrally indistinguishable from the native protein, except most of the recombinant P450foxy was recovered in the soluble fraction of the yeast cells, in marked contrast to native P450foxy, which was exclusively recovered in the membrane fraction of the fungal cells. This difference implies that a post (or co)-translational mechanism functions in the fungal cells to target and bind the protein to the membrane. These results provide conclusive evidence that P450foxy is the eukaryotic counterpart of bacterial P450BM3, which evokes interest in the evolutionary aspects concerning the P450 superfamily along with its reducing systems. P450foxy was classified in the new family, CYP505.
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Affiliation(s)
- T Kitazume
- Institute of Applied Biochemistry, University of Tsukuba, Tsukuba, Ibaraki 305-8572, Japan
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Jin B, Ling Z, Takanishi Y, Ishikawa K, Takezoe H, Fukuda A, Kakimoto M, Kitazume T. Obliquely projecting chiral alkyl chains and their precession around the long core axes in the smectic-A phase of an antiferroelectric liquid crystal. Phys Rev E Stat Phys Plasmas Fluids Relat Interdiscip Topics 1996; 53:R4295-R4298. [PMID: 9964907 DOI: 10.1103/physreve.53.r4295] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
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Tsukamoto T, Kitazume T, McGuire JJ, Coward JK. Synthesis and biological evaluation of DL-4,4-difluoroglutamic acid and DL-gamma,gamma-difluoromethotrexate. J Med Chem 1996; 39:66-72. [PMID: 8568828 DOI: 10.1021/jm950514m] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
DL-4,4-Difluoroglutamic acid (DL-4,4-F2Glu) and its methotrexate analogue, DL-gamma,gamma-difluoromethotrexate (DL-gamma,gamma-F2MTX), were synthesized and evaluated as alternate substrates or inhibitors of folate-dependent enzymes. Synthesis of DL-4,4-F2Glu involved the nitroaldol reaction of ethyl nitroacetate with a difluorinated aldehyde ethyl hemiacetal as a key step. Attempted ligation of DL-4,4-F2Glu to methotrexate (MTX), catalyzed by human folylpoly-gamma-glutamate synthetase (FPGS), revealed that DL-4,4-F2Glu is a poor alternate substrate. DL-gamma,gamma-F2MTX was synthesized by a route proceeding through N-[4-(methylamino)benzoyl]-4,4-difluoroglutamic acid di-tert-butyl ester followed by alkylation with 6-(bromomethyl)-2,4-pteridinediamine hydrobromide. DL-gamma,gamma-F2MTX was found to be neither a substrate nor an inhibitor of human FPGS. The fluorinated analogue of MTX, however, inhibits DHFR and cell growth with the same potency as MTX.
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Affiliation(s)
- T Tsukamoto
- Department of Medicinal Chemistry, University of Michigan, Ann Arbor 48109, USA
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Suzuki Y, Hagiwara T, Kawamura I, Yamazaki T, Kitazume T. Fluorine-containing chiral synthons having trans-/cis-side chain structure for antiferroelectric liquid crystal compounds and their application. J Fluor Chem 1992. [DOI: 10.1016/s0022-1139(00)80850-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Suzuki Y, Hagiwara T, Kawamura I, Negi Y, Yamamoto N, Mori K, Yamada Y, Kitazume T. Fluorine containing chiral synthons for ferro and antiferroelectric liquid crystal compounds and their application. J Fluor Chem 1991. [DOI: 10.1016/s0022-1139(00)83674-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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Watanabe S, Fujita T, Sakamoto M, Endo H, Kitazume T. Fluorination of aromatic α-hydroxyesters with N,N-diethyl-1,1,2,3,3,3-hexafluoropropaneamine. J Fluor Chem 1990. [DOI: 10.1016/s0022-1139(00)82371-4] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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Watanabe S, Fujita T, Sakamoto M, Kitazume T. Reaction of alcohols with N,N-diethyl-1,1,2,3,3,3-hexafluoropropylamine in the presence of diisopropylethylamine. J Fluor Chem 1988. [DOI: 10.1016/s0022-1139(00)82733-5] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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Watanabe S, Fujita T, Sakamoto A, Endo H, Kitazume T. Reactions of nitro alcohols with n,n-diethyl-1,1,2,3,3,3-hexafluoropropylamine. J Fluor Chem 1988. [DOI: 10.1016/s0022-1139(00)83032-8] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Watanabe S, Fujita T, Sakamoto M, Kuramochi T, Kitazume T. Reactions of monoesters of ethylene glycol with N,N-diethyl-1,1,2,3,3,3-hexafluoropropylamine. J Fluor Chem 1987. [DOI: 10.1016/s0022-1139(00)82078-3] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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Affiliation(s)
- S. Watanabe
- ; Department of Applied Chemistry, Faculty of Engineering; Chiba University; Yayoicho 260 Chiba Japan
| | - T. Fujita
- ; Department of Applied Chemistry, Faculty of Engineering; Chiba University; Yayoicho 260 Chiba Japan
| | - M. Sakamoto
- ; Department of Applied Chemistry, Faculty of Engineering; Chiba University; Yayoicho 260 Chiba Japan
| | - H. Endo
- ; Department of Applied Chemistry, Faculty of Engineering; Chiba University; Yayoicho 260 Chiba Japan
| | - T. Kitazume
- ; Department of Bioengineering; Tokyo Institute of Technology; Tokyo Japan
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