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Nagao M, Arakawa K, Takezawa D, Fujikawa S. Long- and short-term freezing induce different types of injury in Arabidopsis thaliana leaf cells. PLANTA 2008; 227:477-489. [PMID: 17924137 DOI: 10.1007/s00425-007-0633-9] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/12/2007] [Accepted: 09/17/2007] [Indexed: 05/25/2023]
Abstract
In nature, intact plant cells are subjected to freezing and can remain frozen for prolonged periods. We assayed the survival of Arabidopsis thaliana leaf cells following freezing and found that short- and long-term exposures produced different types of cellular injury. To identify the cause of these injuries, we examined the ultrastructure of the cell plasma membranes. Our results demonstrate that ultrastructural changes in the plasma membrane due to short-term freezing are associated with interbilayer events, including close apposition of the membranes. In both acclimated and non-acclimated leaf cells, these interbilayer events resulted in "fracture-jump lesions" in the plasma membrane. On the other hand, long-term freezing was associated with the development of extensive protein-free areas caused by the aggregation of intramembrane proteins with consequent vesiculation of the affected membrane regions; this effect was clearly different from the ultrastructural changes induced by interbilayer events. We also found that prolonged exposure of non-acclimated leaf cells to a concentrated electrolyte solution produced effects that were similar to those caused by long-term freezing, suggesting that the ultrastructural changes observed in the plasma membrane following long-term freezing are produced by exposure of the leaf cells to a concentrated electrolyte solution. This study illustrates multiple causes of freezing-induced injury in plant cells and may provide useful information regarding the functional role of the diverse changes that occur during cold acclimation.
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77
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Irie K, Murakami K, Masuda Y, Morimoto A, Ohigashi H, Hara H, Ohashi R, Takegoshi K, Fukuda H, Nagao M, Shimizu T, Shirasawa T. The toxic conformation of the 42-residue amyloid beta peptide and its relevance to oxidative stress in Alzheimer's disease. Mini Rev Med Chem 2007; 7:1001-8. [PMID: 17979802 DOI: 10.2174/138955707782110187] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Senile plaques in the brain of patients with Alzheimer's disease mainly consist of aggregates of amyloid beta peptides (Abeta42, Abeta40). Abeta42 is more neurotoxic than Abeta40. This review describes recent findings from a structural analysis of Abeta42 aggregates and discusses their relevance to neurotoxicity through the formation of radicals.
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78
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Kato H, Maeno Y, Seko-Nakamura Y, Monma-Ohtaki J, Sugiura S, Takahashi K, Zhe LX, Matsumoto T, Kurvanov F, Mizokami M, Nagao M. Identification and phylogenetic analysis of hepatitis C virus in forensic blood samples obtained from injecting drug users. Forensic Sci Int 2007; 168:27-33. [PMID: 16829004 DOI: 10.1016/j.forsciint.2006.06.007] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2006] [Revised: 06/05/2006] [Accepted: 06/06/2006] [Indexed: 01/11/2023]
Abstract
Injecting drug users (IDUs) are a high-risk group for contracting hepatitis B virus (HBV), hepatitis C virus (HCV), and human immunodeficiency virus (HIV) infections. In Japan, data on the prevalence of those blood-borne viruses among IDUs are very limited. Blood samples were obtained from 12 cadavers of IDUs sent to Nagoya City University for the purpose of judicious autopsy and two alive IDUs with hepatitis C referred to a local hospital at the same period. The viruses were detected by polymerase chain reaction and phylogenetic analysis was performed. Two (16.6%) of the 12 autopsy cases were positive for HCV, but no case was positive for either HBV or HIV. Phylogenetic analysis of the two HCV isolates revealed that one was classified into genotype 1b and another was genotype 2b. Furthermore, nucleotide sequences of two isolates recovered from IDUs with hepatitis C were identical, that indicated the transmission of HCV between them, and those HCV were phylogenetically classified into genotype 2a. The prevalence of HCV infection among IDUs in Japan, despite the case of judicious autopsy, seems to be high, but HIV infection seems to be rare. The transmission of HCV between IDUs was demonstrated, and this indicates that phylogenetic analysis would applicable to also forensic analysis. HCV isolates identified in this study did not phylogenetically segregate, thus multiple transmission route of HCV among IDUs seems be exist in Japan.
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79
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Ishizaka K, Eguchi R, Tsuda S, Yokoya T, Chainani A, Kiss T, Shimojima T, Togashi T, Watanabe S, Chen CT, Zhang CQ, Takano Y, Nagao M, Sakaguchi I, Takenouchi T, Kawarada H, Shin S. Observation of a superconducting gap in boron-doped diamond by laser-excited photoemission spectroscopy. PHYSICAL REVIEW LETTERS 2007; 98:047003. [PMID: 17358800 DOI: 10.1103/physrevlett.98.047003] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/04/2006] [Indexed: 05/14/2023]
Abstract
We investigate the temperature (T)-dependent low-energy electronic structure of a boron-doped diamond thin film using ultrahigh resolution laser-excited photoemission spectroscopy. We observe a clear shift of the leading edge below T=11 K, indicative of a superconducting gap opening (Delta approximately 0.78 meV at T=4.5 K). The gap feature is significantly broad and a well-defined quasiparticle peak is lacking even at the lowest temperature of measurement (=4.5 K). We discuss our results in terms of disorder effects on the normal state transport and superconductivity in this system.
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80
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Nagao M, Inoue H, Yanagisawa S. THE PREPARATION AND CHARACTERIZATION OF Cd(XCN)4M TYPE COMPOUNDS. J COORD CHEM 2007. [DOI: 10.1080/00958978008079847] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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81
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Nagao M, Katsunuma T, Kim C, Fujisawa T. Efficacy and Safety of Intravenous Aminophylline in Children with Acute Exacerbation of Asthma: A Multicenter Randomized Trial. J Allergy Clin Immunol 2007. [DOI: 10.1016/j.jaci.2006.11.026] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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82
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Masui Y, Sugaya M, Kagami S, Fujita H, Yano S, Nagao M, Komine M, Saeki H, Ihn H, Kikuchi K, Tamaki K. Sézary syndrome treated with narrowband ultraviolet B: time-course measurement of serum levels of CCL17/CCL27. Clin Exp Dermatol 2006; 32:57-9. [PMID: 17305906 DOI: 10.1111/j.1365-2230.2006.02261.x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
We describe a patient with Sézary syndrome (SS) who was successfully treated with topical steroid and narrowband UVB. Sézary cells in peripheral blood correlated with severity of skin lesions. In addition, serum levels of CCL17 and CCL27 decreased as disease activity improved. These chemokines may be important for the pathogenesis of SS.
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83
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Mizuno T, Nagao M, Yamada Y, Narikiyo M, Ueno M, Miyagishi M, Taira K, Nakajima Y. Small interfering RNA expression vector targeting hypoxia-inducible factor 1 alpha inhibits tumor growth in hepatobiliary and pancreatic cancers. Cancer Gene Ther 2006; 13:131-40. [PMID: 16096651 DOI: 10.1038/sj.cgt.7700871] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Hepatobiliary and pancreatic carcinomas are hypovascular tumors that can proliferate under hypoxic conditions. Recent reports have demonstrated that hypoxia-inducible factor 1 alpha (HIF1alpha) plays an important role in the survival of these cancers. Given these findings, the inhibition of the HIF1alpha pathway might prove to be a powerful tool in the treatment of these cancers. To inhibit HIF1alpha expression, we used small interference RNA (siRNA) expression vectors in this study. The transient transfection of siRNA expression vectors significantly reduced both HIF1alpha mRNA levels (13% of control) and protein levels (41% of control) and significantly inhibited the growth of cancer cell lines (P<0.05). VEGF, Glut1, and aldorase A expressions were also significantly reduced by transfection with these vectors (P<0.05), and we found that these vectors induced apoptosis but not cell cycle arrest. In a subcutaneous tumor model using nude mice, transfected MIA PaCa-2 cells, stably expressing siRNAs, barely formed tumors compared to control (P<0.05). This study thus demonstrates the usefulness of siRNA expression vector in targeting HIF1alpha and points to a potential clinical role in the treatment of pancreatic and hepatobiliary carcinomas.
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84
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Ortolani M, Lupi S, Baldassarre L, Schade U, Calvani P, Takano Y, Nagao M, Takenouchi T, Kawarada H. Low-energy electrodynamics of superconducting diamond. PHYSICAL REVIEW LETTERS 2006; 97:097002. [PMID: 17026393 DOI: 10.1103/physrevlett.97.097002] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/07/2006] [Indexed: 05/12/2023]
Abstract
Heavily boron-doped, diamond films can become superconducting with critical temperatures Tc well above 4 K. Here we first measure the reflectivity of such a film down to 5 cm(-1), by also using coherent synchrotron radiation. We thus determine the optical gap 2Delta, the field penetration depth lambda, the range of action of the Ferrell-Glover-Tinkham sum rule, and the electron-phonon spectral function alpha2F(omega). We conclude that diamond behaves as a dirty BCS superconductor.
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85
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Egawa H, Morita M, Yamaguchi S, Nagao M, Iwasaki T, Hamaguchi S, Kitajima T, Minami J. Comparison Between Intraperitoneal CO2 Insufflation and Abdominal Wall Lift on QT Dispersion and Rate-corrected QT Dispersion During Laparoscopic Cholecystectomy. Surg Laparosc Endosc Percutan Tech 2006; 16:78-81. [PMID: 16773005 DOI: 10.1097/00129689-200604000-00004] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
This study compared the effect of intraperitoneal CO2 insufflation with abdominal wall lift on RR interval, QT interval, the rate-corrected QT (QTc) interval, QT dispersion (QTD), and the rate-corrected QTD (QTcD) using computerized measurement during laparoscopic cholecystectomy. Thirty patients scheduled for laparoscopic cholecystectomy were randomly assigned to 2 groups: intraperitoneal CO2 insufflation (CO2 group) or abdominal wall lift (lift group). A 12-lead electrocardiogram was monitored to measure parameters. The RR interval, QT interval, and QTc interval did not change significantly during the study in both groups. The QTD and QTcD in the CO2 group increased significantly during CO2 insufflation, and were significantly higher than those of the lift group. Statistically significant increases of QTD and QTcD, which are associated with an increased risk of arrhythmias and cardiac events, occur during CO2 insufflation, and QTD and QTcD in the CO2 group were significantly higher than those of the lift group.
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86
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Nagao M, Tokuda R, Noma Y, Nakayama S, Fujisawa T. Novel in Vitro Method for Diagnosis of Food Allergy in Children: Utilization Of CD203c Expression in Basophils. J Allergy Clin Immunol 2006. [DOI: 10.1016/j.jaci.2005.12.165] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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87
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Nagoya S, Nagao M, Takada J, Kaya M, Iwasaki T, Yamashita T. Long-term results of rotational acetabular osteotomy for dysplasia of the hip in adult ambulatory patients with cerebral palsy. THE JOURNAL OF BONE AND JOINT SURGERY. BRITISH VOLUME 2005; 87:1627-30. [PMID: 16326874 DOI: 10.1302/0301-620x.87b12.16664] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
We performed rotational acetabular osteotomy in order to treat dysplasia of the hip in five ambulatory adults with cerebral palsy. There was one man and four women, with a mean age of 21 years (16 to 27) who were followed up for a mean of 12 years and two months. The mean Sharp angle improved from 52 degrees to 43 degrees , the mean acetabular index from 30.2 degrees to 2.8 degrees , the mean centre-edge angle from -5.6 degrees to 29.2 degrees , and the mean acetabular head index from 49.2 to 88.2. There was no progression of joint degeneration and relief from pain was maintained. Our results suggest that rotational acetabular osteotomy is a valuable option for the treatment of acetabular dysplasia in adults with cerebral palsy who have incapacitating pain in the hip.
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88
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Yokoya T, Nakamura T, Matsushita T, Muro T, Takano Y, Nagao M, Takenouchi T, Kawarada H, Oguchi T. Origin of the metallic properties of heavily boron-doped superconducting diamond. Nature 2005; 438:647-50. [PMID: 16319887 DOI: 10.1038/nature04278] [Citation(s) in RCA: 54] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2005] [Accepted: 09/29/2005] [Indexed: 11/09/2022]
Abstract
The physical properties of lightly doped semiconductors are well described by electronic band-structure calculations and impurity energy levels. Such properties form the basis of present-day semiconductor technology. If the doping concentration n exceeds a critical value n(c), the system passes through an insulator-to-metal transition and exhibits metallic behaviour; this is widely accepted to occur as a consequence of the impurity levels merging to form energy bands. However, the electronic structure of semiconductors doped beyond n(c) have not been explored in detail. Therefore, the recent observation of superconductivity emerging near the insulator-to-metal transition in heavily boron-doped diamond has stimulated a discussion on the fundamental origin of the metallic states responsible for the superconductivity. Two approaches have been adopted for describing this metallic state: the introduction of charge carriers into either the impurity bands or the intrinsic diamond bands. Here we show experimentally that the doping-dependent occupied electronic structures are consistent with the diamond bands, indicating that holes in the diamond bands play an essential part in determining the metallic nature of the heavily boron-doped diamond superconductor. This supports the diamond band approach and related predictions, including the possibility of achieving dopant-induced superconductivity in silicon and germanium. It should also provide a foundation for the possible development of diamond-based devices.
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89
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Ohashi K, Kay MA, Kuge H, Yokoyama T, Kanehiro H, Hisanaga M, Ko S, Nagao M, Sho M, Nakajima Y. Heterotopically Transplanted Hepatocyte Survival Depends on Extracellular Matrix Components. Transplant Proc 2005; 37:4587-8. [PMID: 16387176 DOI: 10.1016/j.transproceed.2005.11.049] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The novel approach of tissue engineering to treat many forms of liver diseases using hepatocytes requires sufficient numbers and sustained survival of the transplanted cells. It has been shown that providing extracellular matrix components extracted from Engelbreth-Holm-Swarm cells (EHS-ECMs) to heterotopically transplanted hepatocytes allows significantly greater hepatocyte survival. We investigated the survival and morphology of hepatocytes and EHS-ECMs transplanted under the kidney capsule compared with hepatocytes with growth factor-reduced EHS-ECMs in mice. Both the EHS-ECMs and growth factor-reduced EHS-ECMs showed a large number of surviving hepatocytes under the kidney capsule without any intergroup differences. Histologically, transplanted hepatocytes in both groups retained their characteristic morphologies and formed small liver tissues. These data indicate that extracellular matrix components are the predominant factor in EHS-ECMs required to maintain hepatocytes at heterotopic sites.
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90
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Inomata K, Sato S, Nakajima K, Tanaka A, Takano Y, Wang HB, Nagao M, Hatano H, Kawabata S. Macroscopic quantum tunneling in a d-wave high-TC Bi2Sr2CaCu2O8 + delta superconductor. PHYSICAL REVIEW LETTERS 2005; 95:107005. [PMID: 16196956 DOI: 10.1103/physrevlett.95.107005] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/29/2004] [Indexed: 05/04/2023]
Abstract
While Josephson-junction-like structures intrinsic to the layered cuprate high temperature superconductors offer an attractive stage for exploiting possible applications to new quantum technologies, the low energy quasiparticle excitations characteristically present in these d-wave superconductors may easily destroy the coherence required. Here we demonstrate for the first time the feasibility of macroscopic quantum tunneling in the intrinsic Josephson junctions of a high temperature superconductor Bi(2)Sr(2)CaCu(2)O(8 + delta), and find it to be characterized by a high classic-to-quantum crossover temperature and a relatively weak quasiparticle dissipation.
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91
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Kanaya T, Monkenbusch M, Watanabe H, Nagao M, Richter D. Dynamics of deuterated polystyrene-protonated butadiene diblock copolymer micelles by neutron spin echo. J Chem Phys 2005; 122:144905. [PMID: 15847563 DOI: 10.1063/1.1879892] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
We report on neutron spin-echo (NSE) measurements on deuterated styrene-protonated butadiene diblock copolymer micelles in deuterated n-decane to investigate the dynamics of butadiene blocks in the corona. Before the NSE measurements, we performed small-angle neutron-scattering (SANS) measurements on the micelles to evaluate the structure to give a basis for the discussion of the dynamics. In the SANS study, we have estimated the form factor P(Q) in terms of a hard-core-shell model from the direct evaluation without curve-fitting procedure while a more flexible core-shell model with the structure factor S(Q) gives a better fit to the observed data. The observed normalized intermediate scattering function I(Q,t)/I(Q,0) by NSE does not show the collective motions corresponding to the so-called breathing mode but rather single chain motion (Zimm modes) for both the 2 and 20 wt % micelle solutions. The Zimm decay rate Gamma(z) in the micelle solution is slow compared with that in the homopolymer solution. This slowing down is assigned to the effective high concentration in the corona. The differences in Gamma(z) between concentrated solutions and the 20% micellar solution are attributed to end-tethering effect of the corona chains on the core surface. The possible reasons why the breathing mode was not observed in the present micelle system are discussed on the basis of chain density in the corona.
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92
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Nagao M, Fujisawa T, Kato Y, Noma Y, Katsumata H, Nishimori H, Atsuta J, Iguchi K, Ogawauchi I, Tanaka H, Higashiura M, Kamiya H. Clinical utility of serum TARC/CCL17 levels in children with atopic dermatitis. J Allergy Clin Immunol 2005. [DOI: 10.1016/j.jaci.2004.12.1097] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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93
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Sohmura T, Hojo H, Nakajima M, Wakabayashi K, Nagao M, Iida S, Kitagawa T, Kogo M, Kojima T, Matsumura K, Nakamura T, Takahashi J. Prototype of simulation of orthognathic surgery using a virtual reality haptic device. Int J Oral Maxillofac Surg 2005; 33:740-50. [PMID: 15556320 DOI: 10.1016/j.ijom.2004.03.003] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/24/2004] [Indexed: 11/24/2022]
Abstract
A maxillofacial simulator can support education and training. In the present study, cutting, separation, and quantitative rearrangement of bone during orthognathic surgery were simulated by means of a haptic device with virtual tactile perception. Computed tomographic (CT) images of two patients with severe jaw deformity, one women and one man, were input into the device. In the woman, Le Fort I osteotomy of the maxilla and sagittal splitting ramus osteotomy of the mandible were initially simulated. During surgery with the haptic device, separation and rearrangement of the maxilla and the ramus of the mandible were initially processed. However, there was discrepancy and overlapping of the ramus with the mandible. Intraoral vertical osteotomy of the right ramus was then performed, with satisfactory results and less discrepancy and interference. The simulation was referred to at surgery, and satisfactory surgical assistance was postoperatively confirmed on CT images. The male patient had severe jaw deformity due to unequal growth between the ramuses, resulting in anterior crossbite. Sagittal splitting ramus osteotomy with rotation of the mandible was successfully simulated. Because of its versatility and functions, the present device was found to be useful for simulating various procedures for orthognathic surgery and thereby three-dimensionally determine surgical movements.
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94
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Noma Y, Fujisawa T, Katsumata H, Nagao M, Atsuta J, Iguchi K, Kamiya H. Changing outcome of childhood asthma with increased use of inhaled corticosteroids. J Allergy Clin Immunol 2005. [DOI: 10.1016/j.jaci.2004.12.056] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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95
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Takada Y, Abe O, Nagao M, Suzuki A, Kobayashi M, Oi R, Hashimoto K, Shibuno T. Seasonal Variation of Turbidity in a Fringing Reef Water in Urasoko Bay, Ishigaki Island: Re-suspension due to Northerly Winds. ACTA ACUST UNITED AC 2005. [DOI: 10.3755/jcrs.2005.37] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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96
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Kanaya T, Takahashi N, Nishida K, Seto H, Nagao M, Takeda T. Neutron spin-echo studies on dynamic and static fluctuations in two types of poly(vinyl alcohol) gels. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2005; 71:011801. [PMID: 15697622 DOI: 10.1103/physreve.71.011801] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/16/2004] [Indexed: 05/24/2023]
Abstract
We report neutron spin-echo measurements on two types of poly(vinyl alcohol) (PVA) gels. The first is PVA gel in a mixture of dimethyl sulfoxide (DMSO) and water with volume ratio 60/40 , and the second is PVA gel in an aqueous borax solution. The observed normalized intermediate scattering functions I (Q,t) /I (Q,0) are very different between them. The former I (Q,t) /I (Q,0) shows a nondecaying component in addition to a fast decay, but the latter does not have the nondecaying one. This clearly indicates that the fluctuations in the former PVA gel consist of static and dynamic fluctuations whereas the latter PVA gel does include only the dynamic fluctuations. The dynamic fluctuations of the former and latter gels have been analyzed in terms of a restricted motion in the network and Zimm motion, respectively, and the origins of these motions will be discussed.
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97
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Nakamura H, Hatanaka M, Ochi K, Nagao M, Ogasawara J, Hase A, Kitase T, Haruki K, Nishikawa Y. Listeria monocytogenes isolated from cold-smoked fish products in Osaka City, Japan. Int J Food Microbiol 2004; 94:323-8. [PMID: 15246243 DOI: 10.1016/j.ijfoodmicro.2004.02.010] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2003] [Revised: 11/25/2003] [Accepted: 02/04/2004] [Indexed: 11/30/2022]
Abstract
Listeria monocytogenes contamination of ready-to-eat seafood products commercially available in Osaka was examined between 1999 and 2000. L. monocytogenes was isolated from 12 (13%) of the 95 products tested. All positive samples were from cold-smoked fish with 9 being obtained during the summer. Thirteen isolates of L. monocytogenes were typed by pulsed-field gel electrophoresis (PFGE) and polymerase chain reaction (PCR)-based typing methods. Isolates of the same serotype originating from the same manufacturer gave similar DNA profiles, irrespective of the type of sample or date of isolation. The finding suggest that persistent strains in each manufacturing facility proliferate during the summer and contaminate products during manufacturing processes.
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98
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Hozumi N, Yamashita R, Lee CK, Nagao M, Kobayashi K, Saijo Y, Tanaka M, Tanaka N, Ohtsuki S. Time-frequency analysis for pulse driven ultrasonic microscopy for biological tissue characterization. ULTRASONICS 2004; 42:717-722. [PMID: 15047373 DOI: 10.1016/j.ultras.2003.11.005] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
The authors have proposed a new type of ultrasonic microscopy for biological tissue characterization. The system is driven by a nanosecond pulse voltage, the generated acoustic wave being reflected at the front and rear side of the sliced tissue. In this report, a time-frequency analysis was applied to determine the sound speed thorough the tissue. Frequency dependence of sound speed was obtained with a myocardium of a rat sliced into 10 microm. As the reflected waveform had a significant amount of oscillating component, the waveform was once subjected to the deconvolution process. As the result, two reflections were clearly separated in time domain. Then these two reflections were separately analyzed by time-frequency analysis. Each reflection was extracted by using a proper window function. Phase angles of these reflections at the same frequency were compared. A sound speed micrograph at an arbitrary frequency in between 50 and 150 MHz was successfully obtained. A tendency was found that the sound speed slightly increases with frequency.
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99
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Kawabata Y, Nagao M, Seto H, Komura S, Takeda T, Schwahn D, Yamada NL, Nobutou H. Temperature and pressure effects on the bending modulus of monolayers in a ternary microemulsion. PHYSICAL REVIEW LETTERS 2004; 92:056103. [PMID: 14995321 DOI: 10.1103/physrevlett.92.056103] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/21/2003] [Indexed: 05/24/2023]
Abstract
We performed small-angle neutron scattering and neutron spin echo experiments on a ternary microemulsion composed of ionic surfactant AOT, water, and decane. Thermal fluctuations of monolayers have been investigated as a function of temperature and pressure. The amphiphilic monolayers become more flexible with increasing temperature and more rigid with increasing pressure. These results are consistent with the microscopic picture that the head-head repulsion of the AOT molecules is enhanced at high temperature while an attractive interaction between the hydrophobic tails of the AOT molecules increases at high pressure.
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100
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Kojima T, Sohmura T, Wakabayashi K, Kinuta S, Nagao M, Dei N, Nakamura T, Takahashi J. Computer-assisted morphological analysis of dental casts with maxillary prognathism and reversed occlusion. J Oral Rehabil 2004; 31:29-34. [PMID: 15125593 DOI: 10.1111/j.1365-2842.2004.01199.x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The morphologic characteristics of the dentition with maxillary prognathism and reversed occlusion were examined by a computer-assisted dental cast analysing system. Dental casts with normal occlusion, maxillary prognathism and reversed occlusion were selected and measured by a 3D shape measuring system. The dental arches and anteroposterior occlusal curves were approximated numerically by the polynomial expression with a fourth order and second order coefficients, respectively. The coefficients were analysed statistically. Maxillary dental arches with mandibular prognathism showed a more acuminate shape (V-shape) with a significant larger second order coefficient, while arches with reversed occlusion showed more angulate shapes (U-shape) with significantly smaller second order coefficients compared with arches with normal occlusions. However, a notable difference in the shape of the mandibular dental arches was not observed. The mandibular dental arches with maxillary prognathism were positioned backward relative to maxillary dental arches, while the arches with reversed occlusion were positioned forward. The anteroposterior occlusal curves with maxillary prognathism showed larger curvatures in maxilla and mandible, while the curves with reversed occlusion showed smaller curvatures in mandible comparing with the curves with normal occlusion. These results suggest that the present method could offer a useful and objective examination technique for the diagnosis of malocclusion.
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