Nagasaki-shi, Japan

Nagasaki International University

www.niu.ac.jp
Nagasaki-shi, Japan

Nagasaki International University is a private university in Nagasaki, Nagasaki, Japan, established in 2000. Wikipedia.


Time filter

Source Type

Menezes J.C.J.M.D.S.,University of Aveiro | Menezes J.C.J.M.D.S.,Nagasaki International University
RSC Advances | Year: 2017

Arylidene indanone (AI) scaffolds are considered as the rigid cousins of chalcones, incorporating the α,β-unsaturated ketone system of chalcones forming a cyclic 5 membered ring. They are generally synthesized from 1-indanone and benzaldehydes via an aldol reaction. The furnished molecules have been explored as inhibitors of cholinesterases towards the treatment of Alzheimer’s disease, as tubulin depolymerizing agents, as inhibitors of breast cancer and leukemia, inhibitors of dual specificity phosphatase (DUSP), as antimalarials, and for many other uses. This review is an effort to highlight the biochemical effects of arylidene indanones designed from natural or known drug compounds, discuss their structure-activity relationships (SAR), and correlate them with related chalcones providing insights for further development of this scaffold. © The Royal Society of Chemistry.


Patent
Tokyo Medical, Dental University, Center For Scientific Research Into Plant Medicine, University of Ghana and Nagasaki International University | Date: 2014-01-07

The present invention provides anti-trypanosomal agent for treating, preventing Trypanosomiasis of mammals, which comprises a compound having the tetracyclic iridoid skeleton represented by a general formula (I).


Otera H.,Kyushu University | Wang C.,U.S. National Institutes of Health | Cleland M.M.,U.S. National Institutes of Health | Setoguchi K.,Kyushu University | And 3 more authors.
Journal of Cell Biology | Year: 2010

The cytoplasmic dynamin-related guanosine triphosphatase Drp1 is recruited to mitochondria and mediates mitochondrial fission. Although the mitochondrial outer membrane (MOM) protein Fis1 is thought to be a Drp1 receptor, this has not been confirmed. To analyze the mechanism of Drp1 recruitment, we manipulated the expression of mitochondrial fission and fusion proteins and demonstrated that (a) mitochondrial fission factor (Mff) knockdown released the Drp1 foci from the MOM accompanied by network extension, whereas Mff overexpression stimulated mitochondrial recruitment of Drp1 accompanied by mitochondrial fission; (b) Mff-dependent mitochondrial fission proceeded independent of Fis1; (c) a Mff mutant with the plasma membrane - targeted CAAX motif directed Drp1 to the target membrane; (d) Mff and Drp1 physically interacted in vitro and in vivo; (e) exogenous stimuli - induced mitochondrial fission and apoptosis were compromised by knockdown of Drp1 and Mff but not Fis1; and (f) conditional knockout of Fis1 in colon carcinoma cells revealed that it is dispensable for mitochondrial fission. Thus, Mff functions as an essential factor in mitochondrial recruitment of Drp1. © 2010 Otera et al.


BACKGROUND:: Dabigatran (DT) is a direct thrombin inhibitor used to prevent venous and arterial thromboembolism due to atrial fibrillation. DT is the active form of the commercially available prodrug dabigatran etexilate. Although DT has many clinical advantages over warfarin, it increases the incidence of bleeding in patients with renal dysfunction. Circulating levels of DT are increased in such patients because it is mainly eliminated by renal excretion. Therapeutic drug monitoring may therefore help to prevent adverse DT effects, but no method for measuring circulating DT levels has been reported, except for an analysis by liquid chromatography-tandem mass spectrometry. The present study sought to develop a novel enzyme-linked immunosorbent assay (ELISA) to measure DT concentrations.METHODS:: Mice were immunized with a DT-keyhole limpet hemocyanin conjugate to generate an anti-DT antibody. Immunized mouse splenocytes and myeloma cells (SP2/0) were fused to obtain an anti-DT monoclonal antibody (DT-mAb). DT-mAb and DT solutions were added to microplate wells coated with a DT-human serum albumin conjugate. DT concentrations were determined based on the principles of ELISA.RESULTS:: DT-mAb was successfully purified from a hybridoma, and the competitive ELISA developed using this DT-mAb could evaluate DT concentrations ranging from 7.8 to 125 ng/mL. The ELISA signal was not linear using DT-spiked serum; however, it was linear when serum ultrafiltrate was used. Weak cross-reactivity with dabigatran etexilate was detected, but no cross-reactivity was observed with other structurally related drugs, or drugs commonly used for the treatment of atrial fibrillation.CONCLUSIONS:: The developed competitive ELISA is a valuable and specific tool to analyze free DT in serum ultrafiltrate for therapeutic drug monitoring and pharmacokinetic studies. © 2015 by Lippincott Williams & Wilkins


Onohara Y.,Nagasaki International University | Yokota S.,Nagasaki International University
Histochemistry and Cell Biology | Year: 2012

The localization of DDX25/GRTH and gonadotropin- stimulated RNA helicase was studied in the spermatogenic cells of rat, mouse, and guinea pig by immunofluorescence and immunoelectron microscopy (IEM). Immunofluorescence studies identified four kinds of granular staining: (1) fine particles observed in meiotic cells; (2) small granules associated with a mitochondrial marker, appearing in pachytene spermatocytes after stage V; (3) short strands lacking the mitochondrial marker in late spermatocytes; and, (4) large irregularly shaped granules in round spermatids. IEM identified DDX25 signals in nine compartments: (1) fine dense particles in the meiotic cells; (2) intermitochondrial cement; (3) loose aggregates of 70-90 nm particles; (4) chromatoid bodies; (5) late chromatoid bodies; (6) satellite bodies; (7) granulated bodies; (8) mitochondria-associated granules; and, (9) reticulated bodies. Compartments (1) to (6) were previously classified into nuage while (7) to (9) were classified as nuage components by the present study. The results suggest that DDX25 functions in these nine compartments. © Springer-Verlag 2011.


Yokota S.,Nagasaki International University
Methods in Molecular Biology | Year: 2010

Colloidal gold probes, including protein A-, IgG-F(ab') 2-, and streptavidin-labeled gold particles, are useful tools for localization of antigens in cells and tissues by immunoelectron microscopy (IEM). This chapter describes different methods for the preparation of colloidal gold and conjugation of colloidal gold to protein A, IgG, and streptavidin. © Springer Science+Business Media, LLC 2010.


Yokota S.,Nagasaki International University
Histochemistry and Cell Biology | Year: 2012

Chromatoid body (CB) was identified as granules stained by basic dye 130 years ago and called by various names. Electron microscopy revealed that the CB belonged to nuage (cloud in French) specific for germ cells. We described the localization of several proteins, including RNA helicases, in the nuage compartments classified into six types and in several spermatogenic cell-specific structures. All the proteins examined were detected in the nuage, including the CB with different staining intensities. Several proteins were localized to non-nuage structures, suggesting that these nuage proteins structures are related to nuage function. © Springer-Verlag 2012.


Nawata Y.,Nagasaki International University | Kitaichi K.,Nagasaki International University | Yamamoto T.,Nagasaki International University
Pharmacology Biochemistry and Behavior | Year: 2012

Recent evidence suggests the involvement of corticotropin-releasing factor (CRF) in drug abuse. Here, we evaluated whether CRF modulates the reinstatement of methamphetamine (METH)-seeking behavior induced by stress using a drug-self administration paradigm in rats. Rats were trained to lever-press for intravenous METH (0.02 mg/infusion) accompanied by light and tone (drug-associated cues) and then underwent extinction training (saline substituted for METH without cues). Under the extinction condition, the inhibitory effects of a CRF receptor antagonist on the stress-induced reinstatement of METH-seeking behavior were assessed. Anxiety-like behaviors during METH withdrawal in METH self-administered rats were also evaluated. The non-selective CRF receptor antagonist α-helical CRF 9-41 attenuated METH-seeking behavior induced by footshock stress. CRF levels both in the amygdala and in plasma were significantly increased on day 10 of withdrawal after METH self-administration. However, plasma corticosterone concentrations were unchanged during the withdrawal. In addition, METH-seeking behavior was not affected by an inhibitor of corticosterone synthesis, metyrapone. In the elevated plus maze test, METH self-administered rats showed a decrease in the duration of time spent in the open arms on day 10 of withdrawal. The increased CRF levels in the amygdala may, at least in part, contribute to the footshock-induced reinstatement of METH-seeking behavior and the increase in anxiety-like behavior. The present findings indicate that CRF receptor antagonists would be useful as a therapeutic agent for METH-dependence. © 2012 Elsevier Inc.


Nakahara H.,Nagasaki International University | Shibata O.,Nagasaki International University | Moroi Y.,Nagasaki International University
Journal of Physical Chemistry B | Year: 2011

Several pieces of experimental evidence of condensation of soluble surfactant molecules, cetyltrimethylammonium bromide (CTAB) and sodium dodecyl sulfate (SDS), into the air/water surface region from the bulk solution are presented at different added salt concentrations in order to substantiate that the concentrated molecules do not locate just at the air/solution interface. The insoluble monolayer just at the air/subphase interface for the two surfactants could be studied by surface pressure (π) versus molecular surface area (A), surface potential (ΔV) versus the area (A), infrared absorption of the surface region, and BAM (Brewster angle microscope) image. From surface tension versus concentration curves for the two surfactant solutions, the apparent molecular surface area and the cmc values were determined at different added salt concentrations, and the degree of counterion binding to micelle was found to be 0.70 and 0.73 for CTAB and SDS, respectively. Further examination was made on infrared absorption from the surface region of the surfactant solutions and on BAM images of the surface planes in order to examine the difference between the insoluble monolayer and the condensation in the surface region. Finally, the new concept of bilayer or bilamellar aggregate for soluble surfactant solutions is presented together with the former experimental evidence, which is consistent with several interfacial phenomena of the surfactant solutions. © 2011 American Chemical Society.


Kamiya S.,Nagasaki International University
Yakugaku Zasshi | Year: 2015

The importance of nanoparticle formulation is increasingly recognized in supporting pharmaceutical development. Thus, maintaining nanoparticles in a constant state is a major issue. A method involving lyophilization with the addition of saccharides can be used to maintain the steady state of nanoparticles. In this study, trisaccharides, tetrasaccharides, and pentasaccharides were added to nanoparticle suspensions, followed by rehydration of the samples, which had been either dried normally or freeze-dried. The particle size after rehydration was measured. In addition, each powder was measured using a powder X-ray diffractometer and thermal analysis device to investigate the correlation between the nanoparticles' aggregation and the crystal form of saccharides. The diameter of the nanoparticles was maintained when it was freeze-dried, while particle aggregation occurred when normally dried samples were used. In addition, crystalline saccharide was not observed in the freeze-dried group, but did appear in the normally dried group. © 2015 The Pharmaceutical Society of Japan.

Loading Nagasaki International University collaborators
Loading Nagasaki International University collaborators