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Dive into the research topics where Tatsuo Koide is active.

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Featured researches published by Tatsuo Koide.


Parasitology International | 1998

Oral and Intraperitoneal treatment of Trypanosoma brucei brucei with a combination of ascofuranone and glycerol in mice

Yoshisada Yabu; Nobuko Minagawa; Kiyoshi Kita; Kazuo Nagai; Masakatsu Honma; Shigeru Sakajo; Tatsuo Koide; Nobuo Ohta; Akio Yoshimoto

Abstract On the basis of our previous report of ascofuranone, an antibiotic isolated from Ascochyta visiae , which strongly inhibited both the mitochondrial O 2 consumption in mitochondrial preparation and growth of in vitro cultured bloodstream forms of Trypanosoma brucei brucei in combination with glycerol, we investigated the chemotherapeutic efficacy of ascofuranone on experimental African trypanosomiasis in mice. A suspension of ascofuranone (6–200 mg/kg) was given and then glycerol (1 g/kg) was administered orally or intraperitoneally at 30-min intervals to heavily parasitemic mice. Both orally (100 mg/kg) and intraperitoneally (25 mg/kg) administered ascofuranone combined with a total dose of 3 g/kg glycerol showed potent antitrypanosomal activity in infected mice. The trypanocidal activity of ascofuranone was very powerful and all trypanosomes disappeared within 30 and 180 min after final intraperitoneal and oral treatment, respectively. This combination treatment showed high efficacy and low toxicity. Our results strongly suggest that ascofuranone in combination with glycerol may be an effective tool in chemotherapy for African trypanosomiasis.


International Journal of Pharmaceutics | 2012

Pharmaceutical evaluation of steroidal ointments by ATR-IR chemical imaging: Distribution of active and inactive pharmaceutical ingredients

Yoshihisa Yamamoto; Toshiro Fukami; Tatsuo Koide; Toyofumi Suzuki; Yukio Hiyama; Kazuo Tomono

We recently used micro attenuated total reflection infrared (ATR-IR) spectroscopy to conduct imaging analysis of ointments and evaluate the distributions of the active pharmaceutical ingredient (API) and excipients. An alclometasone dipropionate (ALC) ointment was used as a model product. Almeta, a brand-name product, had a domain with absorbance at 1656 cm(-1) attributable to the carbonyl group of ALC, the API. Absorbances at 1040 and 3300 cm(-1) were also noted in this domain, indicating the presence of the solubilizer, propylene glycol. Data also suggested the presence of benzyl alcohol in this domain. More detailed analysis showed the distribution of surfactants and other excipients in the base. Similar results were obtained for Vitra, a generic version of Almeta. Imaging analysis with micro ATR-IR confirmed that both ointments are liquid droplet dispersions with ALC dissolved in propylene glycol and dispersed in a base. However, minor differences in the ingredient distributions of the two ointments were detected and reflect differences in excipient concentrations and type, or manufacturing differences. In summary, we used micro ATR-IR for imaging analysis of an original ointment, Almeta, and its generic form Vitra, and established a method for visually evaluating the distributions of the API and excipients in these ointments.


International Journal of Pharmaceutics | 2014

Comparative pharmaceutical evaluation of brand and generic clobetasone butyrate ointments

Yoshihisa Yamamoto; Toshiro Fukami; Tatsuo Koide; Yoshinori Onuki; Toyofumi Suzuki; Koichi Metori; Noriko Katori; Yukio Hiyama; Kazuo Tomono

In the present study, we performed comprehensive pharmaceutical evaluation among an original clobetasone butyrate (CLB) ointment product and three generic products. Although spherocrystal images were observed under a polarizing microscope for only Kindavate®, the original product, distribution of active and inactive ingredients was chemically equivalent between the original and generic medicine by the attenuated total reflection infrared spectroscopy. These results suggest that the spherocrystals observed in Kindavate® are composed of hydrocarbon. On GC/MS, it was revealed that linear alkanes having 25-27 carbon atoms are densely present in Sun White®, the base used in Kindavate®. On the other hand, linear alkanes having 22-31 carbon atoms were broadly distributed in most other white petrolatums. In the CLB ointment products, the distribution equivalent of linear alkane to Sun White® was observed only in Kindavate®. Thus, the GC/MS method is extremely useful for identification of white petrolatum used in the ointment. A similar amount of CLB among the pharmaceutical products was detected in the skin tissue by skin accumulation test, although there were the differences in rheological properties and the quality of white petrolatum. The present results will be very useful for pharmacists in selecting medicine products that match the needs of the patient. Such pharmaceutical information will help spread objective knowledge about products in the future, and will contribute to the appropriate selection of medication.


Chemical & Pharmaceutical Bulletin | 2015

Magnetic Resonance Imaging of the Phase Separation in Mixed Preparations of Moisturizing Cream and Steroid Ointment after Centrifugation

Yoshinori Onuki; Chiaki Funatani; Takashi Yokawa; Yoshihisa Yamamoto; Toshiro Fukami; Tatsuo Koide; Yasuko Obata; Kozo Takayama

A mixed preparation consisting of a water-in-oil emulsion-type moisturizing cream and a steroid ointment is frequently prescribed for the treatment of atopic dermatitis. We have investigated the compatibility of moisturizing creams and ointments because there are concerns regarding the physical stability of these mixed preparations. The key technology used in this study was magnetic resonance imaging (MRI). A commercial moisturizing cream and white petrolatum or clobetasone butyrate (CLB) ointment samples were mixed in a weight ratio of 1 : 1. A centrifugation test protocol (20000×g for 3 min) was implemented to accelerate the destabilization processes in the samples. After centrifugation, the mixed preparations separated into three distinct layers (upper, middle, and lower), while no phase separation was observed using moisturizing cream alone. The phase separation was monitored using chemical shift selective images of water and oil and quantitative T2 maps. In addition, MR and near-infrared spectroscopy were employed for component analysis of each phase-separated layer. Collectively, it was confirmed that the lower layer contained water, oils, and organic solvent, while the upper and middle layers were composed solely of oils. Furthermore, this study investigated the distribution of CLB in the phase-separated samples and showed that a heterogeneous distribution existed. From our results, it was confirmed that the mixed preparation became unstable because of the incompatibility of the moisturizing cream and ointment.


International Journal of Pharmaceutics | 2013

Detection of component segregation in granules manufactured by high shear granulation with over-granulation conditions using near-infrared chemical imaging.

Tatsuo Koide; Takuya Nagato; Yoshiyuki Kanou; Kou Matsui; Susumu Natsuyama; Toru Kawanishi; Yukio Hiyama

The objective of this study was to evaluate the high shear granulation process using near-infrared (NIR) chemical imaging technique and to make the findings available for pharmaceutical development. We prepared granules and tablets made under appropriate- and over-granulation conditions with high shear granulation and observed these granules and tablets using NIR chemical imaging system. We found an interesting phenomenon: lactose agglomeration and segregation of ingredients occurred in experimental tablets when over-granulation conditions, including greater impeller rotation speeds and longer granulation times, were employed. Granules prepared using over-granulation conditions were larger and had progressed to the consolidation stage; segregation between ethenzamide and lactose occurred within larger granules. The segregation observed here is not detectable using conventional analytical technologies such as high pressure liquid chromatography (HPLC) because the content of the granules remained uniform despite the segregation. Therefore, granule visualization using NIR chemical imaging is an effective method for investigating and evaluating the granulation process.


Chemical & Pharmaceutical Bulletin | 2015

Analysis of Distribution of Ingredients in Commercially Available Clarithromycin Tablets Using Near-Infrared Chemical Imaging with Principal Component Analysis and Partial Least Squares

Tatsuo Koide; Yoshihisa Yamamoto; Toshiro Fukami; Noriko Katori; Haruhiro Okuda; Yukio Hiyama

The aim of this study was to evaluate pharmaceuticals using a near-infrared chemical imaging (NIR-CI) technique for visualizing the distribution of ingredients in solid dosage forms of commercially available clarithromycin tablets. The cross section of a tablet was measured using the NIR-CI system for evaluating the distribution of ingredients in the tablet. The chemical images were generated by performing multivariate analysis methods: principal component analysis (PCA) and partial least squares (PLS) with normalized near-infrared (NIR) spectral data. We gained spectral and distributional information related to clarithromycin, cornstarch, and magnesium stearate by using PCA analysis. On the basis of this information, the distribution images of these ingredients were generated using PLS analysis. The results of PCA analysis enabled us to analyze individual components by using PLS even if sufficient information on the products was not available. However, some ingredients such as binder could not be detected using NIR-CI, because their particle sizes were smaller than the pixel size (approximately 25×25×50 µm) and they were present in low concentrations. The combined analysis using both PCA and PLS with NIR-CI was useful to analyze the distribution of ingredients in a commercially available pharmaceutical even when sufficient information on the product is not available.


Chemical & Pharmaceutical Bulletin | 2016

Analysis of the Stability of External-Application Dermatologic Preparations: Consideration from Rheological Measurements

Yoshihisa Yamamoto; Moemi Kumetani; Yoshinori Onuki; Tatsuo Koide; Toyofumi Suzuki; Toshiro Fukami

The present study examined the stability of mixtures of various combinations of moisturizers, water in oil (w/o)-type or oil in water (o/w)-type cream preparations containing heparinoids, and steroidal ointments or creams (o/w-type) frequently used in children. Centrifugation at room temperature led to separation of mixtures of w/o-type moisturizers and steroidal ointments into three layers. Polarized microscopic observations, near-infrared (NIR) spectroscopy, and dye-based analyses revealed the presence of oily components in the upper and middle layers and water-soluble components in the lower layer. Separation into three layers upon centrifugation was also observed for mixtures of o/w-type moisturizers and steroidal ointments. In contrast, neither the o/w-type moisturizer and steroidal cream nor the w/o-type moisturizer and steroidal cream mixtures separated into layers upon centrifugation. Consideration of the characteristics of each preparation is necessary when mixing external-application dermatologic preparations. Centrifugation at 4°C did not result in layer separation of the w/o-type moisturizer and steroidal ointment mixture, suggesting that cold storage of such mixtures provides superior stability compared with room temperature storage. However, despite no obvious layer separation, the NIR spectra indicated that water movement was induced within the mixture. These results clearly indicate that methods such as NIR spectroscopy are useful for early determinations of the stability of mixed external-application dermatologic preparations.


International Journal of Pharmaceutics | 2018

In situ monitoring of cocrystals in formulation development using low-frequency Raman spectroscopy

Takashi Otaki; Yuta Tanabe; Takashi Kojima; Masaru Miura; Yukihiro Ikeda; Tatsuo Koide; Toshiro Fukami

&NA; In recent years, to guarantee a quality‐by‐design approach to the development of pharmaceutical products, it is important to identify properties of raw materials and excipients in order to determine critical process parameters and critical quality attributes. Feedback obtained from real‐time analyses using various process analytical technology (PAT) tools has been actively investigated. In this study, in situ monitoring using low‐frequency (LF) Raman spectroscopy (10–200 cm−1), which may have higher discriminative ability among polymorphs than near‐infrared spectroscopy and conventional Raman spectroscopy (200–1800 cm−1), was investigated as a possible application to PAT. This is because LF‐Raman spectroscopy obtains information about intermolecular and/or lattice vibrations in the solid state. The monitoring results obtained from Furosemide/Nicotinamide cocrystal indicate that LF‐Raman spectroscopy is applicable to in situ monitoring of suspension and fluidized bed granulation processes, and is an effective technique as a PAT tool to detect the conversion risk of cocrystals. LF‐Raman spectroscopy is also used as a PAT tool to monitor reactions, crystallizations, and manufacturing processes of drug substances and products. In addition, a sequence of conversion behaviors of Furosemide/Nicotinamide cocrystals was determined by performing in situ monitoring for the first time.


European Journal of Pharmaceutical Sciences | 2018

Mixtures of betamethasone butyrate propionate ointments and heparinoid oil-based cream: Physical stability evaluation

Yoshihisa Yamamoto; Akane Hanai; Yoshinori Onuki; Mika Fujii; Yu Onishi; Toshiro Fukami; Koichi Metori; Naoto Suzuki; Toyofumi Suzuki; Tatsuo Koide

ABSTRACT Betamethasone butyrate propionate ointment (BBPO) is mainly used for adult patients in dermatology and is often prescribed as a mixture containing a base or moisturizing cream for various reasons. However, in the case of a moisturizing cream, since this formulation is composed of various ingredients, a physical change is expected to occur by mixing it with an ointment. Therefore, in the present study, the physical stability of a mixture of four BBPO formulations and heparinoid oily cream (HPOC) was examined. Layer separation was observed in all mixtures following centrifugation. The near‐infrared (NIR) measurement showed a peak at 5200cm−1 on the lower layer side, which strongly suggests the presence of water. The peak at 5200cm−1 in the middle layer was hardly observed in the mixtures of two BBPO generic formulations and HPOC, thus suggesting that the separation was more advanced in those mixtures than in the others. These two mixtures separated into a semisolid layer (upper side) and a liquid layer (lower side) after 3h of storage at 37°C. The NIR measurement of each layer revealed that most of the semisolid layer was oil while the liquid layer was water. Furthermore, backscattered light measurements were conducted to monitor the behavior of the mixtures layer separation. An evaluation using model formulations revealed that the layer separation of the mixtures was due to the propylene glycol (PG) and surfactant content of the two generic BBPO formulations. Thus, these findings suggest that excipients need to be considered in selecting formulations for mixtures of skin preparations.


Biological & Pharmaceutical Bulletin | 2018

Molecular State of Active Pharmaceutical Ingredients in Ketoprofen Dermal Patches Characterized by Pharmaceutical Evaluation

Motoshige Azuma; Mika Fujii; Motoki Inoue; Hiroshi Hisada; Tatsuo Koide; Mark Kemper; Yoshihisa Yamamoto; Naoto Suzuki; Toyofumi Suzuki; Toshiro Fukami

The molecular states of ketoprofen and the interaction between ketoprofen and other pharmaceutical excipients in the matrix layer were examined to determine their effect on the pharmaceutical properties of original and generic ketoprofen dermal patches (generic patches A and B). Molecular states of ketoprofen were evaluated using polarized light microscopy, Raman spectroscopy and powder X-ray diffraction. For the original ketoprofen patch, crystalline components were not observed in the matrix layer. However, crystalline ketoprofen was observed in the two generic ketoprofen patches. Moreover, the ketoprofen exhibited hydrogen bonding with the pharmaceutical excipients or patch materials in the generic products. Skin permeation of ketoprofen from the patches was evaluated using hairless mouse skin. Twelve hours after application, the original patch demonstrated the highest level of cumulative skin permeation of ketoprofen. This was followed by generic patch B while generic patch A showed the lowest level of permeation. Fluxes were calculated from the skin permeation profiles. The original patch was approx. 2.4-times faster compared with generic patch A and approximately 1.9-times faster compared with generic patch B. This investigation suggested that pharmaceutical properties such as skin permeability for these types of products are affected by the precipitation of crystalline ketoprofen in the matrix layer and the interaction of ketoprofen with the pharmaceutical excipients or patch materials.

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Toshiro Fukami

Meiji Pharmaceutical University

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Motoki Inoue

Meiji Pharmaceutical University

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Hiroshi Hisada

Meiji Pharmaceutical University

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Nobuo Ohta

Tokyo Medical and Dental University

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