Kumamoto University

About: Kumamoto University is a education organization based out in Kumamoto, Kumamoto, Japan. It is known for research contribution in the topics: Cancer & Population. The organization has 19602 authors who have published 35513 publications receiving 901260 citations. The organization is also known as: Kumamoto Daigaku.

Nature of copper(II)-lanthanide(III) magnetic interactions and generation of a large magnetic moment with magnetic anisotropy of 3d-4f cyclic cylindrical tetranuclear complexes [CuIILLnIII(hfac)2]2, (H3L = 1-(2-hydroxybenzamido)-2-(2-hydroxy-3-methoxybenzylideneamino)ethane and Hhfac = hexafluoroacetylacetone, LnIII = Eu, Gd, Tb, Dy).

Abstract: A cyclic cylindrical 3d-4f tetranuclear structure, in which the 3d and 4f magnetic ions are arrayed alternately, has been found to be a suitable molecular design to produce a large magnetic moment and large magnetic anisotropy. Complexes 3-10 with the chemical formula [MLLn(hfac)2]2 ((MII, LnIII) = (Cu, Eu) (3), (Cu, Gd) (4), (Cu, Tb) (5), (Cu, Dy) (6), (Ni, Eu) (7), (Ni, Gd) (8), (Ni, Tb) (9), (Ni, Dy) (10)) have been synthesized, where H3L = 1-(2-hydroxybenzamido)-2-(2-hydroxy-3-methoxybenzylideneamino)ethane and Hhfac = hexafluoroacetylacetone. The powder X-ray diffractions and FAB-mass spectra demonstrated that these complexes assume a similar tetranuclear structure. The crystal structures of 4 and 5 showed that each complex has a cyclic cylindrical tetranuclear CuII2LnIII2 structure, in which the CuII complex functions as a "bridging ligand-complex" to two adjacent LnIII ions. The temperature-dependent magnetic susceptibilities from 2 to 300 K and the field-dependent magnetizations at 2 K from 0 to 5 T have been measured for four pairs of CuII2LnIII2 and NiII2LnIII2, in which compound NiII2LnIII2 containing diamagnetic NiII ion was used as the reference complex to evaluate the CuII-LnIII magnetic interaction. Comparison of the magnetic properties of the CuII2LnIII2 complex with those of the corresponding NiII2LnIII2 complex showed that the magnetic interaction between CuII and EuIII ions is weakly ferromagnetic and that between CuII and either of GdIII, TbIII, and DyIII ions is ferromagnetic. Complex CuII2GdIII2, 4, has an S = 8 spin ground state, due to the ferromagnetic spin coupling between SGd = 7/2 and SCu = 1/2 with coupling constants of J1 = +3.1 cm-1 and J2 = +1.2 cm-1. The magnetic measurements showed that compounds 5 and 6, CuII2LnIII2 (LnIII = Tb, Dy), exhibit large magnetic moments and large magnetic anisotropy due to the LnIII ion.

The expression of c-kit protein during oogenesis and early embryonic development.

Abstract: The c-kit proto-oncogene encodes a transmembrane tyrosine kinase receptor and was shown to be allelic with the white-spotting locus (W) of the mouse. Mutations at the W locus have pleiotropic effects on the development of hematopoietic stem cells, melanoblasts, and primordial germ cells. In order to elucidate the role of c-kit protein in gametogenesis and oocyte maturation, we have examined immunohistochemically the expression of c-kit in the ovaries of mice at late fetal and postnatal stages, and in early embryos. By the avidin-biotin-peroxidase (ABC) method using rat anti-mouse c-kit monoclonal antibody, the c-kit protein was detected in ovaries after the time of birth, but not before. The expression of c-kit was observed mainly on the surface of oocytes, but not in granulosa cells nor in interstitial regions. Oocytes of primordial to fully grown Graafian follicles showed the c-kit protein. When ovulation was induced by hCG, the expression of c-kit in ovulated unfertilized oocytes was weaker than in oocytes of Graafian follicles. In 1-cell embryos the c-kit protein was still observed, but with cell division its expression further decreased, and it was not detected in embryos of 4-cell, 8-cell, and morula stages. In summary, the highest expression of c-kit was observed on the surface of oocytes arrested in the diplotene stage of meiotic prophase. With ovulation and the resumption of meiotic maturation, its expression declined. These results suggest that the c-kit protein may play some role in meiotic arrest, oocyte growth, and oocyte maturation.

FANTOM5 CAGE profiles of human and mouse samples

Abstract: In the FANTOM5 project, transcription initiation events across the human and mouse genomes were mapped at a single base-pair resolution and their frequencies were monitored by CAGE (Cap Analysis of Gene Expression) coupled with single-molecule sequencing. Approximately three thousands of samples, consisting of a variety of primary cells, tissues, cell lines, and time series samples during cell activation and development, were subjected to a uniform pipeline of CAGE data production. The analysis pipeline started by measuring RNA extracts to assess their quality, and continued to CAGE library production by using a robotic or a manual workflow, single molecule sequencing, and computational processing to generate frequencies of transcription initiation. Resulting data represents the consequence of transcriptional regulation in each analyzed state of mammalian cells. Non-overlapping peaks over the CAGE profiles, approximately 200,000 and 150,000 peaks for the human and mouse genomes, were identified and annotated to provide precise location of known promoters as well as novel ones, and to quantify their activities.

Evaluating of arsenic(V) removal from water by weak-base anion exchange adsorbents

Abstract: Arsenic contamination of groundwater has been called the largest mass poisoning calamity in human history and creates severe health problems. The effective adsorbents are imperative in response to the widespread removal of toxic arsenic exposure through drinking water. Evaluation of arsenic(V) removal from water by weak-base anion exchange adsorbents was studied in this paper, aiming at the determination of the effects of pH, competing anions, and feed flow rates to improvement on remediation. Two types of weak-base adsorbents were used to evaluate arsenic(V) removal efficiency both in batch and column approaches. Anion selectivity was determined by both adsorbents in batch method as equilibrium As(V) adsorption capacities. Column studies were performed in fixed-bed experiments using both adsorbent packed columns, and kinetic performance was dependent on the feed flow rate and competing anions. The weak-base adsorbents clarified that these are selective to arsenic(V) over competition of chloride, nitrate, and sulfate anions. The solution pH played an important role in arsenic(V) removal, and a higher pH can cause lower adsorption capacities. A low concentration level of arsenic(V) was also removed by these adsorbents even at a high flow rate of 250–350 h−1. Adsorbed arsenic(V) was quantitatively eluted with 1 M HCl acid and regenerated into hydrochloride form simultaneously for the next adsorption operation after rinsing with water. The weak-base anion exchange adsorbents are to be an effective means to remove arsenic(V) from drinking water. The fast adsorption rate and the excellent adsorption capacity in the neutral pH range will render this removal technique attractive in practical use in chemical industry.

Effects of topical administration of y-39983, a selective rho-associated protein kinase inhibitor, on ocular tissues in rabbits and monkeys.

Abstract: Purpose To elucidate the intraocular pressure (IOP)-lowering effects and associated characteristics of Y-39983, a selective Rho-associated coiled coil-forming protein kinase (ROCK) inhibitor derived from Y-27632, in animal eyes. Methods Y-39983 was compared with Y-27632 for selectivity of ROCK inhibition by biochemical assay. The IOP was monitored by pneumatonometer in albino rabbits and cynomolgus monkeys that were given topically administered Y-39983. The total outflow facility and uveoscleral outflow were measured by two-level constant-pressure perfusion and perfusion technique using fluorescein isothiocyanate-dextran, respectively, at 2 hours after topical administration of Y-39983 in albino rabbits. The ocular toxicologic effects of topical administration of Y-39983 were observed in albino rabbits and cynomolgus monkeys. Results A biochemical assay showed that Y-39983 inhibited ROCK more potently than Y-27632. In rabbits, topical administration of Y-39983 significantly increased conventional outflow by 65.5%, followed by significant, dose-dependent reduction in IOP. Maximum IOP reduction was 13.2 +/- 0.6 mm Hg (mean +/- SE) at 0.1% Y-39983 in rabbits. In monkeys, at 3 hours after topical administration of 0.05% Y-39983, maximum reduction of IOP was 2.5 +/- 0.8 mm Hg. No serious side effects were observed in ocular tissues except sporadic punctate subconjunctival hemorrhage during long-term topical administration of Y-39983 four times a day (at 2-hour intervals) in rabbits or monkeys. However, punctate subconjunctival hemorrhage was not observed with administration twice daily (at a 6-hour interval) or three times a day (at 5-hour intervals). Conclusions Y-39983 causes increased outflow facility followed by IOP reduction. Y-39983 ophthalmic solution may be a candidate drug for lowering of IOP, since it increases conventional outflow and produces relatively few side effects.