Species composition and abundance of craneflies (Diptera: Tipulidae) in the highland lakes of Japan

We evaluated the relative abundance of tipulids in the Nishina Three Lakes and Lake Suwa, Japan, by capturing adult flies with light traps set around the shores of the lakes. Of the 149 individuals collected, 49 species were identified, and we described 19 newly recorded genera around these lakes. We collected seven species of adults at Lake Suwa, 27 species at Lake Aoki, 19 species at Lake Nakatsuna, and 16 species at Lake Kizaki. The most abundant species were Antocha bifida, Gonomyia (Leiponeura) incompleta, and Gonomyia sp. However, the most abundant species of each lake differed. Only A. bifida was collected from all the lakes. We calculated the Shannon-Wiener diversity index to compare the tipulid fauna among the lakes. The diversity index was the highest at 4.24 in Lake Aoki (an oligotrophic lake) and the lowest at 2.81 in Lake Suwa (a hypereutrophic lake). These results suggest that the diversity and relative abundance of adult tipulid species may be useful biological indicators for water quality assessment.ArticleJOURNAL OF FRESHWATER ECOLOGY. 26(1):91-97 (2011)journal articl

Vesicle formation in mixture of a PEO-PPO-PEO block copolymer (Pluronic P123) and a nonionic surfactant (Span 65) in water

Fabrication of vesicles with the diameter of 4-30 mu m was achieved by mixing hydrophobic nonionic surfactant (Span 65) with a poly(ethylene oxide)-poly(propylene oxide)-poly(ethylene oxide) block copolymer (Pluronic P123) in aqueous solutions at room temperature. Ring-shaped structure of the Plutonic P123/Span 65 mixture assemblies was confirmed by fluorescence microscopy. The presence of internal aqueous phase in the Pluronic P123/Span 65 mixture assemblies was determined by measuring the entrapment efficiency of calcein using fluorescence spectroscopy. On the other hand, Pluronic P123/Span 60 mixture system formed wire-like assemblies but not vesicles.ArticleCOLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS. 389(1-3):82-89 (2011)journal articl

Titania/C-n TAB Nanoskeleton as adsorbent and photocatalyst for removal of alkylphenols dissolved in water

We report here on the removal of alkylphenols (phenol, 4-n-propylphenol, 4-n-heptylphenol and 4-nonylphenol) dissolved in water using the composite particles of nanocrystalline titania and alkyltrimethylammonium bromide (CnH2n+1N(CH3)(3)Br, C(n)TAB; n = 12, 14, 16 and 18) (named as TiO2/C(n)TAB Nanoskeleton) as adsorbents and photocatalysts. In particular, the adsorption of alkylphenols onto TiO2/C(n)TAB Nanoskeleton in water was investigated in terms of hydrophobic interaction between alkylphenols and C(n)TAB, surface area, pore structure and crystal size of TiO2/C(n)TAB Nanoskeleton. We revealed that C(n)TAB incorporated in the TiO2/C(n)TAB Nanoskeleton promotes the adsorption of alkylphenols onto TiO2/C(n)TAB Nanoskeleton due to the hydrophobic interaction between alkylphenols and C(n)TAB. On the other hand, the surface area, pore structure and crystal size of TiO2/C(n)TAB Nanoskeleton did not affect the adsorption of allcylphenols onto TiO2/C(n)TAB Nanoskeleton. We also found that the alkylphenols dissolved in water were completely removed by the combination of adsorption and photocatalytic degradation by the TiO2/C(n)TAB Nanoskeleton under UV irradiation. These results prove that the TiO2/C(n)TAB Nanoskeleton acts as in tandem an adsorbent and a photocatalyst for removal of alkylphenols dissolved in water.ArticleJOURNAL OF HAZARDOUS MATERIALS. 248:487-495 (2013)journal articl

Block copolymer-mediated synthesis of gold nanoparticles in aqueous solutions: Segment effect on gold ion reduction, stabilization, and particle morphology

We report here on the segment effects of poly(ethylene oxide)-containing block copolymers (PEO-BCP) on the reduction activity for tetrachloride gold(III) ([AuCl4](-)), interfacial activity for gold surface, colloidal stability, and morphology of gold nanoparticles formed in aqueous solutions. In particular, the effects of poly(ethylene oxide) (PEO), poly(propylene oxide) (PPO), polyethylene (PE) segments and amino group (NH2) on the rate of [AuCl4](-) reduction, adsorption of PEO-BCP onto gold surface, colloidal stability, and morphology of gold nanoparticles formed in aqueous solutions were examined using a poly(ethylene oxide)-poly(propylene oxide) triblock copolymer (PEO-PPO-PEO, Pluronic L44), an amino-terminated poly(ethylene oxide)-poly(propylene oxide) block copolymer (PEO-PPO-NH2, SURFONAMINE(R) L-207), a poly(ethylene oxide) homopolymer (PEO, poly(ethylene glycol)2000), and a polyethylene-poly(ethylene oxide) block copolymer (PE-PEO). We found that the reduction activity of PEO-BCP for [AuCl4](-) became higher with the order of PEO-PPO-NH2 < PE-PEO < PEO < PEO-PPO-PEO. The interfacial activity (affinity) of PEO-BCP for gold surface increased with the order of PEO < PE-PEO < PEO-PPO-PEO < PEO-PPO-NH2. Consequently, the colloidal stability of gold nanoparticles formed in aqueous PEO-PPO-NH2 solutions was extremely high compared with that in PEO, PEO-PPO-PEO, and PE-PEO solutions. In addition, the size of gold nanoparticles formed in aqueous PEO-PPO-NH2 solutions was much smaller than that in aqueous solutions of PEO-PPO-PEO, PEO or PE-PEO.ArticleJOURNAL OF COLLOID AND INTERFACE SCIENCE. 394:124-131 (2013)journal articl

Increased prostaglandin e2 has a positive correlation with plasma calcium during goldfish reproduction

We recently demonstrated that prostaglandin E2 PG¿ increases osteoclastic activity and induces bone resorption in both in vitro and in vivo experiments using goldfish. In the fish reproductive period, the plasma calcium (Ca) level in female teleosts increases remarkably to make vitellogenin, which is a major component of egg protein and a Ca-binding protein. In this period, however, there is no reported relationship between PGE2 and Ca metabolism in fish. To clarify the Ca metabolism in fish reproduction, we examined plasma PGE2 and Ca levels and measured tartrate-resistant acid phosphatase (TRAP) activities as an indicator of osteoclastic activity in goldfish. Plasma PGE2 levels in the reproductive stage significantly increased as compared with those in non-reproductive stages. Also, both plasma Ca and TRAP increased in the reproductive stage. Significant positive correlations were recognized between plasma Ca and the gonad somatic index (r=0.81, p<0.001), plasma Ca and plasma PGE2 levels (r=0.635, p<0.05), and plasma Ca and plasma TRAP activities (r=0.584, p<0.05) from the analysis using samples of both reproductive and nonreproductive stages. Taking these data into consideration, we suggested that PGE, acts on osteoclasts and increases plasma Ca as a result of osteoclastic bone resorption, and we concluded that PGE, is an important hormone in Ca metabolism during fish reproduction

Effects of low-intensity pulsed ultrasound on osteoclasts: Analysis with goldfish scales as a model of bone

The effects of low-intensity pulsed ultrasound (LIPUS) on osteoclastogenesis were examined using fish scales that had both osteoclasts and osteoblasts. The binding of the receptor activator of NF-κB ligand (RANKL) in osteoblasts to the receptor activator of NF-κB (RANK) in osteoclasts induced osteoclastogenesis. Therefore, we focused on RANK/RANKL signaling. After 6 h of incubation following LIPUS treatment, mRNA expression of RANKL increased significantly. Resulting from the increased RANKL mRNA level, the expression of transcription-regulating factors significantly increased after 6 h of incubation, and then the mRNA expression of functional genes was significantly up-regulated after 12 h of incubation. However, the mRNA expression of osteoprotegerin (OPG), which is known as an osteoclastogenesis inhibitory factor, also significantly increased after 6 h of incubation and tended to further increase after 12 h of incubation. At 24 h of incubation, osteoclastic functional genes’ mRNA expression decreased to the level of the control. Furthermore, we performed an in vivo experiment with goldfish. Two weeks after daily LIPUS exposure, osteoclastic marker enzymes tended to decrease while osteoblastic marker enzymes were activated. The regeneration rate of the LIPUS-treated scales was significantly higher than that of the control scales. Thus, LIPUS moderately activates osteoclasts and induces bone formation. © 2017 Biomedical Research Foundation. All rights reserved

Sodium fluoride induces hypercalcemia resulting from the upregulation of both osteoblastic and osteoclastic activities in goldfish, Carassius auratus

The influence of sodium fluoride (NaF) on calcium metabolism was examined in goldfish (fresh water teleost). At 2 days after administration of NaF (500 ng/g body weight; 5 μg/g body weight) (around 10− 5 to 10− 4 M in goldfish), we indicated that plasma calcium levels upregulated in both doses of NaF-treated goldfish. To examine the mechanism of hypercalcemia by NaF treatments, therefore, direct effects of NaF on osteoblasts and osteoclasts in goldfish were investigated by an original assay system using teleost scale which has osteoblasts, osteoclasts and bone matrix. Alkaline phosphatase activity in the scales increased with the treatment of NaF (10− 6 and 10− 5 M) during 6 h of incubation. Also, tartrate-resistant acid phosphatase activity increased after exposure to NaF (10− 5 M) at the 6 h of incubation. To investigate the osteoclastic activation, the mRNA expression of osteoclastogenesis related factors were examined. The receptor activator of the nuclear factor-κB ligand (RANKL) which is known as a factor for osteoclastogenesis, increased in the NaF-treated scales after 6 h of incubation. The ratio of RANKL/osteoprotegerin (osteoclastogenesis inhibitory factor) significantly increased after 6 h of incubation. Resulting from the increase of RANKL mRNA level, the expression of transcription-regulating factors was significantly increased. Furthermore, the expression of functional genes, cathepsin K and matrix metalloproteinase-9 mRNA, was significantly increased. In our knowledge, this is the first report concerning the effects of NaF on osteoblasts and osteoclasts in teleosts. We concluded that NaF influences calcium metabolism via osteoclastic activation in goldfish. © 2016 Elsevier Inc.Embargo Period 12 month