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Muraoka H, Kaneda T, Sasaki Y, Kawashima Y, Fukuda T, Muramatsu T, Ito K, Hirahara N. Relationship between joint effusion and parotid lymph nodes in temporomandibular disorders. J Oral Maxillofac Surg 2014. [DOI: 10.1016/j.joms.2014.06.398] [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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Kaneda T, Kawashima Y, Sasaki Y, Suemitsu M, Okada H, Hayakawa Y, Sakae T, Muraoka H, Hirahara N. Clinical application of parameteric X-ray in diagnostic imaging: Preliminary study. J Oral Maxillofac Surg 2014. [DOI: 10.1016/j.joms.2014.06.312] [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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Kawashima Y, Fukuda K, Kaneko H, Yamauchi Y, Uchikawa K. Additivity of vection speed induced by fast and slow spatially-overlapped optical flows. J Vis 2013. [DOI: 10.1167/13.9.955] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
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Nagahara A, Mitani A, Fukuda M, Yamamoto H, Tahara K, Morita I, Ting CC, Watanabe T, Fujimura T, Osawa K, Sato S, Takahashi S, Iwamura Y, Kuroyanagi T, Kawashima Y, Noguchi T. Antimicrobial photodynamic therapy using a diode laser with a potential new photosensitizer, indocyanine green-loaded nanospheres, may be effective for the clearance of Porphyromonas gingivalis. J Periodontal Res 2013; 48:591-9. [PMID: 23317284 DOI: 10.1111/jre.12042] [Citation(s) in RCA: 80] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/12/2012] [Indexed: 12/20/2022]
Abstract
BACKGROUND Antimicrobial photodynamic therapy (aPDT) is a new treatment method for the removal of infectious pathogens using a photosensitizer and light of a specific wavelength, e.g., toluidine blue with a wavelength of about 600 nm. We explored a new photosensitizer and focused on indocyanine green (ICG), which has high absorption at a wavelength of 800-805 nm. We investigated the bactericidal effect of PDT on Porphyromonas gingivalis using a new photosensitizer, ICG-loaded nanospheres with an 805 nm wavelength low-level diode laser irradiation. METHODS We designed ICG-loaded nanospheres coated with chitosan (ICG-Nano/c) as a photosensitizer. A solution containing Porphyromonas gingivalis (10(8) CFU/mL) with or without ICG-Nano/c (or ICG) was prepared and irradiated with a diode laser or without laser irradiation as a negative control. The irradiation settings were 0.5 W with a duty ratio of 10%, for 3-100 ms in repeated pulse (RPT) or continuous wave mode. CFU were counted after 7 d of anaerobic culture. RESULTS We observed that ICG-Nano/c could adhere to the surface of P. gingivalis. When ICG-Nano/c was used for aPDT, irradiation with RPT 100 ms mode gave the lowest increase in temperature. Laser irradiation with ICG-Nano/c significantly reduced the number of P. gingivalis (i.e., approximately 2-log10 bacterial killing). The greatest bactericidal effect was found in the RPT 100 ms group. However, laser irradiation (RPT 100 ms) with ICG, as well as without photosensitizer, had no effect on the number of bacteria. CONCLUSIONS Within the limits of this study, ICG-Nano/c with low-level diode laser (0.5 W; 805 nm) irradiation showed an aPDT-like effect, which might be useful for a potential photodynamic periodontal therapy.
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Eishima J, Sato J, Tsunoda K, Kawakami N, Sato R, Kawashima Y, Hoshino H, Kubota T, Suzuki S, Ito J. EP-1260 EVALUATION OF THE EFFECT OF RADIOTHERAPY IN BONE METASTASIS PATIENTS BY THE BONE SCAN INDEX. Radiother Oncol 2012. [DOI: 10.1016/s0167-8140(12)71593-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Honein K, Kaneko G, Katsuyama I, Matsumoto M, Kawashima Y, Yamada M, Watabe S. Studies on the Cellulose-Degrading System in a Shipworm and its Potential Applications. ACTA ACUST UNITED AC 2012. [DOI: 10.1016/j.egypro.2012.05.143] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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Kawashima Y, Uchikawa K, Kaneko H, Fukuda K, Yamamoto K, Kiya K. Vection stimuli placed on a road modulate driver's speed sensation in a real driving scene. J Vis 2011. [DOI: 10.1167/11.11.913] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
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Horie M, Kawashima Y, Naka A, Matsumoto K, Kodera Y, Maeda T, Iida K. Proteomic Profiling of K-11706 Responsive Proteins. Int J Sports Med 2011; 32:559-64. [DOI: 10.1055/s-0031-1273741] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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Sunose Y, Takeyoshi I, Ohwada S, Iwazaki S, Tsutsumi H, Kawashima Y, Oriuchi N, Matsumoto K, Morishita Y. FR183998 protects against the increased microvascular permeability associated with ischemia-reperfusion injury in the canine lung. Int J Angiol 2011. [DOI: 10.1007/bf01616494] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022] Open
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Hino T, Takeuchi H, Niwa T, Kitagawa M, Kawashima Y. The Analysis of Drug Release from Diluted Water/oil/water Emulsions by a Model of the Rupture of Oil Membrane. J Pharm Pharmacol 2011. [DOI: 10.1111/j.2042-7158.1995.tb05724.x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Abstract
The release behaviour of theophylline encapsulated in the inner aqueous phase of a water/oil/water emulsion was investigated by two methods. A cellulose tube containing a sample of the emulsion was placed in a rotary basket and was stirred in a dissolution medium (Method A), or the w/o/w emulsion was dispersed in a dissolution medium and the system was stirred by a paddle, allowing the drug to permeate into a cellulose tube placed in the dispersing medium (Method B).
In Method A, the drug release rate from the emulsion decreased with increase in the concentration of sodium chloride co-formulated with the drug in the inner aqueous phase. The drug release rate in the dissolution test medium No. 1 or No. 2 of the JP XII was greater than that in purified water and was increased with the ionic strength of the dissolution medium. The drug was released more rapidly in Method B than in Method A, because the emulsion was destroyed more easily using the former method. As this destruction of emulsion structure occurred immediately after dilution with dissolution medium, the influence of the dissolution medium on the release profile could not be detected using Method B.
The experimental data of drug release were satisfactorily explained by the destruction model of the oil membranes of the water/oil/water emulsions.
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Takada K, Saito M, Tsuzukibashi O, Kawashima Y, Ishida S, Hirasawa M. Characterization of a new serotype g isolate of Aggregatibacter actinomycetemcomitans. Mol Oral Microbiol 2010; 25:200-6. [DOI: 10.1111/j.2041-1014.2010.00572.x] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Yoshikawa T, Sasako M, Yamamoto S, Sano T, Imamura H, Fujitani K, Oshita H, Ito S, Kawashima Y, Fukushima N. Phase II study of neoadjuvant chemotherapy and extended surgery for locally advanced gastric cancer. Br J Surg 2009; 96:1015-22. [PMID: 19644974 DOI: 10.1002/bjs.6665] [Citation(s) in RCA: 169] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
BACKGROUND Locally advanced gastric cancer with extensive lymph node metastasis is usually considered unresectable and so treated by chemotherapy. This trial explored the safety and efficacy of preoperative chemotherapy followed by extended surgery in the management of locally advanced gastric adenocarcinoma. METHODS Patients with gastric cancer with extensive lymph node metastasis received two or three 28-day cycles of induction chemotherapy with irinotecan (70 mg/m(2) on days 1 and 15) and cisplatin (80 mg/m(2) on day 1), and then underwent gastrectomy with curative intent with D2 plus para-aortic lymphadenectomy. Primary endpoints were 3-year overall survival and incidence of treatment-related death. RESULTS The study was terminated because of three treatment-related deaths when 55 patients had been enrolled (mortality rate above 5 per cent). Two deaths were due to myelosuppression and one to postoperative complications. Clinical response and R0 resection rates were 55 and 65 per cent respectively. The pathological response rate was 15 per cent. Median overall survival was 14.6 months and the 3-year survival rate 27 per cent. CONCLUSION This multimodal treatment of locally advanced gastric cancer provides reasonable 3-year survival compared with historical data, but at a considerable cost in terms of morbidity and mortality.
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Hosoda S, Nozue Y, Kawashima Y, Utsumi S, Nagamatsu T, Wagener K, Berda E, Rojas G, Baughman T, Leonard J. Perfectly Controlled Lamella Thickness and Thickness Distribution: A Morphological Study on ADMET Polyolefins. ACTA ACUST UNITED AC 2009. [DOI: 10.1002/masy.200950806] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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Kawashima Y, Chen J, Sun H, Lann D, Hajjar RJ, Yakar S, Leroith D. Apolipoprotein E deficiency abrogates insulin resistance in a mouse model of type 2 diabetes mellitus. Diabetologia 2009; 52:1434-41. [PMID: 19436992 PMCID: PMC5488278 DOI: 10.1007/s00125-009-1378-8] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/19/2009] [Accepted: 03/16/2009] [Indexed: 01/22/2023]
Abstract
AIMS/HYPOTHESIS Although it is known that lipid metabolism plays a role in insulin resistance in type 2 diabetes and in obesity, the mechanism is still largely unknown. Apolipoprotein E (ApoE) regulates plasma lipid levels and also plays a role in the uptake of lipids into various tissues. To investigate whether the suppression of whole-particle lipoprotein uptake into tissues affects insulin responsiveness and the diabetic condition, we examined the effect of an ApoE (also known as Apoe) gene deletion in MKR mice, a mouse model of type 2 diabetes. METHODS ApoE ( -/- ), MKR, ApoE ( -/- )/MKR and control mice were placed on a high-fat, high-cholesterol diet for 16 weeks. Glucose tolerance, serum insulin, blood glucose, insulin tolerance, tissue triacylglycerol content and atherosclerotic lesions were assessed. RESULTS ApoE ( -/- )/MKR and ApoE ( -/- ) mice showed significantly improved blood glucose, glucose tolerance and insulin sensitivity. Reduced triacylglycerol content in liver and reduced fat accumulation in liver and adipose tissue were found in ApoE ( -/- )/MKR and ApoE ( -/- ) mice compared with control and MKR mice. ApoE ( -/- ) and ApoE ( -/- )/MKR mice demonstrated similarly large atherosclerotic lesions, whereas MKR and control mice had small atherosclerotic lesions. CONCLUSIONS/INTERPRETATION We demonstrated that ApoE deficiency abrogates insulin resistance in a mouse model of type 2 diabetes, suggesting that lipid accumulation in tissue is a major cause of insulin resistance in this mouse model.
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Taniguchi K, Kawamaoto T, Kuki S, Masai T, Mitsuno M, Nakano S, Kawashima Y, Matsuda H. Left ventricular myocardial remodeling and contractile state in chronic aortic regurgitation. Clin Cardiol 2009; 23:608-14. [PMID: 10941548 PMCID: PMC6654784 DOI: 10.1002/clc.4960230812] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND In chronic aortic regurgitation, eccentric hypertrophy, with combined concentric hypertrophy of the left ventricle, is an important adaptive response to volume overload, which in itself is a compensatory mechanism for permitting the ventricle to normalize its afterload and to maintain normal ejection performance (physiologic hypertrophy). However, progressive dilatation of the left ventricle leads to depressed left ventricular (LV) contractility and myocardial structural changes, including cellular hypertrophy and interstitial fibrosis (pathological hypertrophy). HYPOTHESIS The study was undertaken to determine the relationship between left ventricular myocardial structure and contractile function in 14 patients with chronic aortic regurgitation by cardiac catheterization and endomyocardial biopsies. METHODS Myocardial cell diameter and percent interstitial fibrosis were obtained from biopsy samples. Contractile function was evaluated from the ratio of end-systolic wall stress to end-systolic volume index (ESS/ESVI) and the ejection fraction-end-systolic stress (EF-ESS) relationship, which was obtained from 30 normal control subjects. RESULTS Myocardial cell diameter correlated significantly with the ESVI (r = 0.72, p < 0.005), ejection fraction (r = -0.58, p < 0.05), and ESS/ESVI (r = -0.58, p < 0.05). The percent interstitial fibrosis also correlated inversely with ESS/ESVI (r = -0.71, p < 0.005). Compared with very few patients with an ESVI < 70 ml/m2, the majority of patients with ESVI > or = 70 ml/m2 had a cell diameter of > or = 30 microns and a percent interstitial fibrosis of > or = 10%. The nine patients who had depressed contractile function, as assessed from the EF-ESS relationship, had a higher percent interstitial fibrosis (p < 0.05) than five patients showing a normal EF-ESS relationship, despite the fact that there was no significant difference in myocardial cell diameter between them. Thus, advanced cellular hypertrophy and excessive interstitial fibrosis were significantly and independently associated with myocardial contractile dysfunction and appeared to be responsible for ventricular remodeling. CONCLUSION Our findings suggest that in many patients with aortic regurgitation, eccentric hypertrophy changes its nature from physiologic to nonphysiologic during the earlier stages in the course of the disease rather than during the stage described previously.
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Thongborisute J, Takeuchi H, Yamamoto H, Kawashima Y. Visualization of the Penetrative and Mucoadhesive Properties of Chitosan and Chitosan-Coated Liposomes Through the Rat Intestine. J Liposome Res 2008; 16:127-41. [PMID: 16753967 DOI: 10.1080/08982100600680816] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
The objectives of this study were to observe the penetrative and mucoadhesive behavior of polymer-coated liposomes into the intestinal mucosa of rats. Chitosan (CS) and negatively charged liposomes were chosen as model polymer-coated liposomes. In order to observe their behavior, chitosan was labeled with Fluorescence Isothiocyanate (FITC) via chemical reaction at the isothiocyanate group of FITC and the primary amino group of chitosan; the liposomes (Lips) were marked by incorporation of DiI into the liposomal formulation. FITC-labeled chitosan (FITC-CS), Non-Lips, and FITC-labeled CS-coated Liposomes (FITC-CS-Lips) were intragastrically administered into male Wistar rats, and the behavior of the molecules was subsequently visualized by CLSM (Confocal Laser Scanning Microscopy). The results demonstrated that the chitosan molecules themselves, as well as the liposomes, could penetrate across the intestinal mucosa. Moreover, the CLSM images demonstrated a lack of separation of the chitosan molecules from the surface of the liposomes after the administration of chitosan-coated liposomes.
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Shi K, Cui F, Yamamoto H, Kawashima Y. Investigation of drug loading and in vitro release mechanisms of insulin-lauryl sulfate complex loaded PLGA nanoparticles. DIE PHARMAZIE 2008; 63:866-871. [PMID: 19177901] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Insulin, a water soluble peptide hormone, was hydrophobically ion-paired with sodium lauryl sulfate (SDS) at the stoichiometric molar ratio of 6:1. The obtained insulin-SDS complex precipitation was subsequently formulated in biodegradable poly (D,L-lactic-co-glycolic acid) (PLGA) nanoparticles by a modified spontaneous emulsion solvent diffusion method. Compared with a conventional method for free insulin encapsulation, direct dissolution of SDS-paired insulin in the non-aqueous organic phase led to an increase in drug recovery from 42.5% to 89.6%. The more hydrophobic complex contributes to the improved affinity of insulin to the polymer matrix, resulting in a higher drug content in the nanoparticles. The drug loading was investigated by determining initial burst release at the first 30 min. The results showed that 64.8% of recovered drug were preferentially surface bound on complex loaded nanoparticles. The in vitro drug release was characterized by an initial burst and subsequent delayed release in dissolution media of deionized water and phosphate buffer saline (PBS). Compared with that in PBS, nanoparticles in deionized water medium presented very low initial burst release (15% vs. 65%) and incomplete cumulative release (25% vs. 90%) of the drug. In addition, dialysis experiments were performed to clarify the form of the released insulin in the dissolution media. The results suggested that the ion-pair complex was sensitive to ionic strength, insulin was released from the particular matrix as complex form and subsequently suffered dissociation from SDS in buffer saline. Moreover, the in vivo bioactivity of the SDS-paired insulin and nanoparticulate formulations were evaluated in mice by estimation of their blood sugar levels. The results showed that the bioactivity of insulin was unaltered after the ion-pairing process.
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Kawashima Y, Lin SY, Kasai A, Takenaka H, Matsunami K, Nochida Y, Hirose H. Drug Release Properties of the Microcapsules of Adriamycin Hydrochloride with Ethylcellulose Prepared by a Phase Separation Technique. Drug Dev Ind Pharm 2008. [DOI: 10.3109/03639048409041400] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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Kawashima Y, Lin SY, Takenaka H. Polymorphism and drug release behavior of spray-dried microcapsules of sulfamethoxazole with polysaccharide gum and colloidal silica. Drug Dev Ind Pharm 2008. [DOI: 10.3109/03639048309052387] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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Kawashima Y, Lin SY, Ueda M, Takenaka H. Preparations of Solid Particulates of Amino-Pyrine-Barbital Complex (Pyrabital) wiithout Autoxidation Ey a Spray Drying Technique. Drug Dev Ind Pharm 2008. [DOI: 10.3109/03639048309044675] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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Shi K, Cui F, Yamamoto H, Kawashima Y. Optimized preparation of insulin-lauryl sulfate complex loaded poly (lactide-co-glycolide) nanoparticles using response surface methodology. DIE PHARMAZIE 2008; 63:721-725. [PMID: 18972833] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Insulin-lauryl sulfate (INS-SDS) complex loaded poly (lactic acid-co-glycolic acid) (PLGA) nanoparticles were prepared by spontaneous emulsion solvent diffusion method. To improve the insulin entrapment efficiency (E.E), a five-level-two-factor central composite design and surface response methodology (RSM) was used to determine the optimum levels of PLGA/INS complex weight ratio and PVA/ acetone volume ratio, two important variables during nanoparticles fabrication. A quadratic model to express the E.E as a function of the two studied factors was developed. Only 10 experimental runs were necessary and the obtained model was adequate (P < 0.05). By partial derivative resolution of regression model, the optimum weight ratio of PLGA/INS complex and volume ratio of PVA/acetone was determined as 25/1 and 10/1, respectively. This preparing condition resulted E.E of insulin as high as 91% during nanoparticles production. Validation of the model was accomplished by experiments carried out on optimized formulation conditions. The experimental results were in good agreement with those predicted by the model. The results indicated that RSM represents an effective and potential technique for formulation optimization.
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Higuchi Y, Taketa M, Ohik T, Yasuhira K, Kawashima Y, Takeo M, Kato D, Negoro S, Nakagawa A, Inaka K, Tanaka H, Sato M, Kobayashi T, Tanaka T, Shibata N. Evolution of nylon oligomer degrading enzyme based on high-resolution crystal structure analysis. Acta Crystallogr A 2008. [DOI: 10.1107/s0108767308091782] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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Sun S, Cui F, Kawashima Y, Liang N, Zhang L, Shi K, Yu Y. A novel insulin-sodium oleate complex for oral administration: preparation, characterization and in vivo evaluation. J Drug Deliv Sci Technol 2008. [DOI: 10.1016/s1773-2247(08)50047-5] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Yang M, Velaga S, Yamamoto H, Takeuchi H, Kawashima Y, Hovgaard L, van de Weert M, Frokjaer S. Characterisation of salmon calcitonin in spray-dried powder for inhalationEffect of chitosan. Int J Pharm 2007; 331:176-81. [PMID: 17126507 DOI: 10.1016/j.ijpharm.2006.10.030] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2006] [Revised: 10/16/2006] [Accepted: 10/18/2006] [Indexed: 11/17/2022]
Abstract
Salmon calcitonin (sCT) powders suitable for inhalation, containing chitosan and mannitol as absorption enhancer and protection agent, respectively, were prepared using a spray-drying process. The effect of chitosan on physicochemical stability of sCT in the dry powder was investigated by different analytical techniques. High-performance liquid chromatography (HPLC) analysis indicated that sCT was chemically stable upon spray-drying. With the proportion of chitosan in spray-drying formulation being increased, dissolution of sCT from the dry powders was decreased both in phosphate buffer and acetate buffer. The thioflavine T fluorescence assay showed that no fibrils were present in the spray-dried powder. However, sCT partly fibrillated in the phosphate buffer, but not in acetate buffer. Fourier transform infrared (FTIR) spectra showed that the secondary structure of sCT was slightly changed in the dry powder, yet no aggregate signal was observed. Circular dichroism analysis indicated that the structure of sCT in an aqueous formulation was slightly altered by addition of chitosan. Nevertheless, recovery of sCT was not influenced by chitosan in the aqueous formulation as indicated by HPLC analysis. This study suggested that sCT, in absence of any additives, was stable during the spray-drying process under certain conditions. Addition of chitosan affects recovery of sCT from spray-dried powders, which may be due to formation of a partially irreversible complex between the protein and chitosan during the spray-drying process.
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Kawashima Y, Sasaki YC, Sugita Y, Yoda T, Okamoto Y. Replica-exchange molecular dynamics simulation of diffracted X-ray tracking. MOLECULAR SIMULATION 2007. [DOI: 10.1080/08927020601067581] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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