A Report on Overseas Teaching Practicum by Graduate Students in Elementary/Secondary Schools in the United States (Ⅶ)

The present reports is on the 7th overseas teaching practicum in the United States by 15 graduate students of Hiroshima University, Japan, partly organized by Hiroshima University Global Partnership School Center since 2007. The group was comprised of 13 elementary school and 2 secondary school education major graduate students. They planned and conducted lessons in English in three local public schools in North Carolina. The expected outcomes of this project were: 1) to self-develop practical instructional competence by teaching pupils with diverse backgrounds in the U.S.; 2) to enhance the abilities in developing teaching materials through hands-on teaching experiences in English; and 3) to acquire the abilities to design, implement and evaluate programs for promoting global partnership. In addition, the teaching experience was followed by cross-cultural study visits to Raleigh, NC and Washington, D.C. It helped to boost our group motivation that the local media, newspaper and TV, and the city Board of Education covered our visit. It is hoped that this project will enhance the students’ teaching competence in designing quality materials/lessons and classroom communication skills in English

Multielectron reduction of molecular oxygen in photocatalytic decomposition of organic compounds by bismuth tungstate particles without cocatalyst loading

A photocatalytic reaction mechanism that involves multielectron reduction of molecular oxygen (O-2), as a key step, in photocatalytic decomposition of acetic acid by pristine bismuth tungstate (Bi2WO6; BWO) particles is proposed on the basis of results of studies on (i) comparison of photocatalytic activity trends of BWO, tungsten (VI) oxide and titanium(IV) oxide photocatalyst powders with or without platinum deposits in three photocatalytic reaction systems (oxidative decomposition of acetic acid in aerobic aqueous suspensions, methanol dehydrogenation in deaerated aqueous suspensions and O-2 liberation from deaerated silver salt solutions) and (ii) effects of morphology and structural properties of BWO particles on photocatalytic activities

Purification and characterization of a novel incomplete-type vitellogenin protein (VgC) in Sakhalin taimen (Hucho perryi)

A novel, incomplete-type vitellogenin (VgC) and its derived yolk lipovitellin (LvC) were immunologically detected in female serum and egg extracts, respectively, of Sakhalin taimen (Hucho perryi) using a subtype-specific antiserum against LvC of grey mullet (Mugil cephalus). The taimen VgC was purified from the sera of vitellogenic females by a combination of gel filtration, anion exchange, and immunoadsorbent column chromatography. Gel filtration of the purified VgC revealed that it had an apparent native mass of ∼380 kDa, while the mass of the VgC polypeptide that appeared following SDS-PAGE was estimated to be ∼140 kDa. An antiserum was raised against the purified VgC and utilized for the development of a subtype-specific immunoassay for VgC. Levels of VgC in the serum of female taimen increased from 25 μg/mL to ∼1 mg/mL, with an increase of GSI. Levels of complete-type Vg and estradiol-17β (E2) in the serum of E2-administered juvenile taimen increased and reached peak levels similar to those found in vitellogenic females. Although VgC could be induced in the serum of E2-administered taimen, it stayed at levels (35.5-73 μg/mL) lower than those obtained in females. This is the first report on the presence of serum VgC and yolk LvC in a salmonid species; these findings indicate that for Sakhalin taimen, like other highly-evolved teleost species, this minor subtype of Vg is significant in the formation of egg yolk

Multiple vitellogenin yolk precursors in European sea bass (Dicentrarchus labrax)

Trabajo presentado en el 10th International Symposium on Reproductive Physiology of Fish (Expanding the knowledge base of reproductive process: from genes to the environment), celebrado en Olhao (Portugal) del 25 al 30 de mayo de 2014.We characterized three deduced sea bass vitellogenin (Vtg) polypeptides with regard to linear and 3-dimensional (3-D) structural and functional features, verified the presence and relative contribution to the yolk of each form of Vtg, and assessed maturational degradation and potential contribution of each product lipovitellin (Lv) to the free amino acid (FAA) pool driving oocyte hydrat ion and supporting early embryonic nutrition.Peer Reviewe

Purification of multiple vitellogenins in grey mullet (Mugil cephalus)

Three female specific serum proteins were detected immunologically in the sera of grey mullet (Mugil cephalus) which were named vitellogenin A (VgA), VgB, and VgC, based upon their distinct antigenicity against specific antisera raised against three types of mullet lipovitellins (Lvs). These Vgs were subsequently purified from the serum of estradiol-treated mullet by combining several types of chromatography columns (anion exchanger, hydroxylapatite, immunoadsorbent column, and gel filtration). Purified native VgA, VgB, and VgC exhibited molecular masses of 570, 580, and 335 kDa, respectively. Following, SDS-PAGE, the estimated mass of polypeptide bands evident for VgA and VgB were ~179 kDa and ~175 kDa, respectively; VgC appeared to be ~132 kDa. The two larger Vgs (VgA and VgB) appeared to be phosphorylated, suggesting that these Vgs contain a highly phosphorylated, serine-rich phosvitin (Pv) domain. Furthermore, two discrete Vg-type specific antisera, anti-VgA and anti-VgB, were developed and each generated two precipitin lines against ovary extracts in immunoelectrophoresis, indicating that these Vgs contain additional antigenic yolk protein domains: Lv and β'-component. The small Vg (VgC) appeared to lack a Pv domain because of its low serine content (5.35%) and failure to show positive results in phospho-staining experiments. In conjunction with N-terminal amino acid sequencing analyses of the purified Vgs, our present results have conclusively identified the purified Vg products in grey mullet as typical A-type (VgA), B-type (VgB), and C-type (VgC) Vgs

Estrogen-inducible yolk precursors: Characterization of the multiple vitellogenin system in European sea bass (Dicentrachus labrax)

Trabajo presentado en la 27th Conference of European Comparative Endocrinologists (CECE 2014), celebrada en Rennes (Francia) del 25 al 29 de agosto de 2014.This study explored multiplicity of the estrogen-inducible yolk precursor protein, vitellogenin (Vtg), in the European sea bass (Sbs), a major aquaculture species and leading model in fish endocrinology. Three full-length Sbs vtg cDNAs were assembled from partial cDNAs that were cloned and sequenced from total RNA isolated from estradiol-induced male livers. Homology analyses of the deduced polypeptides via BLAST and ClustalW alignments with available Vtg sequences for teleosts from a broad array of taxa identified them as as Sbs VtgAa, VtgAb and VtgC. Analyses of conservation by Vtg-type of the key structural residues, cysteine (C), proline (P) and glycine (G) using Evotrace and their localization in the 3-D polypeptide structures modelled using Cn3D with a lamprey lipovitellin (Lv) template indicated that the N-sheet of the Lv domain of SbsVtgC, which bears the binding surface for the 'classical' Vtg receptor (Vtgr), has undergone massive alteration of its structure relative to the A-type Sbs Vtgs that may explain the limited Vtgr-binding reported for this form of Vtg. The presence and relative concentrations of each form of Sbs Vtg or product YP in postvitellogenic female liver, plasma and ovary were measured by nanoLC-MS/MS as ProteoIQ-normalized spectral counts. VtgAb tryptic peptide spectra were two- to several-fold more abundant than for the other Vtgs, and VtgC spectra were very limited except in ovary where they were a third of VtgAb spectral counts. Western blotting performed using antisera raised against purified grey mullet (Mugil cephalus) Lvs revealed limited degradation of all three forms of Lv during oocyte maturation, unlike the case in other marine pelagic spawners where only the LvAa undergoes almost complete proteolysis to free amino acids (FAA), which are important osmotic effectors of oocyte hydration and egg buoyancy. The nearly identical Vtgs and patterns of YP degradation during oocyte maturation in sea bass and Moronidae spawning demersal or pelagic eggs in freshwater indicate that Vtg system structure and function cannot be inferred solely from reproductive life history.N

Estrogen-induced yolk precursors in European sea bass, Dicentrarchus labrax: Status and perspectives on multiplicity and functioning of vitellogenins

The estrogen-inducible egg yolk precursor, vitellogenin, of the European sea bass (Dicentrarchus labrax) has received considerable scientific attention by virtue of its central importance in determination of oocyte growth and egg quality in this important aquaculture species. However, the multiplicity of vitellogenins in the sea bass has only recently been examined. Recent cloning and homology analyses have revealed that the sea bass possesses the three forms of vitellogenin, VtgAa, VtgAb and VtgC, reported to occur in some other highly evolved teleosts. Progress has been made in assessing the relative abundance and special structural features of the three Vtgs and their likely roles in oocyte maturation and embryonic nutrition. This report discusses these findings in the context of our prior knowledge of vitellogenesis in this species and of the latest advances in our understanding of the evolution and function of multiple Vtgs in acanthomorph fishes

Multiple vitellogenins and product yolk proteins in European sea bass (Dicentrarchus labrax): Molecular characterization, quantification in plasma, liver and ovary, and maturational proteolysis.

Three complete vitellogenin (Vtg) polypeptides of European sea bass (Dicentrarchus labrax), an acanthomorph teleost spawning pelagic eggs in seawater, were deduced from cDNA and identified as VtgAa, VtgAb and VtgC based on current Vtg nomenclature and phylogeny. Label free quantitative mass spectrometry verified the presence of the three sea bass Vtgs or their product yolk proteins (YPs) in liver, plasma and ovary of postvitellogenic females. As evidenced by normalized spectral counts, VtgAb-derived protein was 2- to 5-fold more abundant, depending on sample type, than for VtgAa, while VtgC-derived protein was less abundant, albeit only 3-fold lower than for VtgAb in the ovary. Western blotting with Vtg type-specific antisera raised against corresponding gray mullet (Mugil cephalus) lipovitellins (Lvs) detected all three types of sea bass Vtg in the blood plasma of gravid females and/or estrogenized males and showed that all three forms of sea bass Lv undergo limited partial degradation during oocyte maturation. The comparatively high levels of VtgC-derived YPs in fully-grown oocytes and the maturational proteolysis of all three types of Lv differ from what has been reported for other teleosts spawning pelagic eggs in seawater but are similar to recent findings for two species of North American Moronidae, the striped bass (Morone saxatilis) and white perch (Morone americana), which spawn pelagic and demersal eggs, respectively in fresh water. Together with the high Vtg sequence homologies and virtually identical structural features of each type of Vtg between species, these findings indicate that the moronid multiple Vtg systems do not substantially vary with reproductive environment

Estrogen-induced yolk precursors in European sea bass, Dicentrarchus labrax: Status and perspectives on multiplicity and functioning of vitellogenins

The estrogen-inducible egg yolk precursor, vitellogenin, of the European sea bass (Dicentrarchus labrax) has received considerable scientific attention by virtue of its central importance in determination of oocyte growth and egg quality in this important aquaculture species. However, the multiplicity of vitellogenins in the sea bass has only recently been examined. Recent cloning and homology analyses have revealed that the sea bass possesses the three forms of vitellogenin, VtgAa, VtgAb and VtgC, reported to occur in some other highly evolved teleosts. Progress has been made in assessing the relative abundance and special structural features of the three Vtgs and their likely roles in oocyte maturation and embryonic nutrition. This report discusses these findings in the context of our prior knowledge of vitellogenesis in this species and of the latest advances in our understanding of the evolution and function of multiple Vtgs in acanthomorph fishesThis research was supported by an Akdeniz University Scientific Research Coordinating Unit Ph.D. research grant (2009.03.0121.008) and a Fulbright Doctoral Research fellowship granted to O.Y., and by awards from the North Carolina Sea Grant Program (award number R/12-SSS-3), the North Carolina Agricultural Foundation, Inc., and Carolina AquaGyn to CVS.Peer Reviewe