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This study aimed to detect filarial parasites in blood samples of Japanese black bears (Ursus thibetanus japonicus) collected from Iwate Prefecture, Japan. Positive amplicons were obtained from 26 out of 30 samples by nested PCR targeting 18S ribosomal RNA gene and first internal transcribed spacer regions. DNA sequences of Mansonella sp. close to M. ozzardi and Dirofilaria sp. were detected for eight and 11 positive amplicons, respectively. Co-infection was detected for the remaining seven amplicons. Dirofilaria sp. was identified as D. ursi by further genetic analysis of 5S ribosomal RNA gene sequence. The results of this study will contribute to further investigations of Japanese black bears for monitoring their risk as a reservoir of possible zoonotic filarial parasites.

The cytosolic sulfotransferase 1 (SULT1) proteins are a family of highly divergent proteins that show variable expansion in different species during vertebrate evolution. To clarify the evolutionary origin of the mammalian lineage of the SULT1 family, we compiled Xenopus laevis and X. tropicalis SULT1 (XSULT1) sequences from public databases. The XSULT1 family was found to comprise at least six subfamilies, which corresponded in part to five mammalian SULT1 subfamilies but only poorly to zebrafish SULT1 subfamilies. SULT1C was most highly expanded, and could be divided into at least five subfamilies. A cDNA for X. laevis SULT1B (XlSULT1B.S), a homolog of mammalian SULT1B1, was cloned and its recombinant protein was expressed in a bacterial system. XlSULT1B.S, unlike mammalian SULT1B1, was found to be a monomeric protein of ~34 kDa, and displayed sulfonating activity toward 2-naphthol and p-nitrophenol (pNP). However, we could not detect such sulfonating activity toward any endogenous compounds including thyroid hormones, steroid hormones and dopamine, despite the fact that X. laevis and Rana catesbeiana liver cytosols contained sulfonating activity toward most of these endogenous compounds. At optimum pH (6.4), the Michaelis-Menten constant (Km) for pNP was two orders of magnitude greater in XlSULT1B.S (1.04 mM) than in the cytosol preparations (8-15 μM). Our results indicate that Xenopus possesses a prototype of the mammalian SULT1 family, and that XlSULT1B.S showed overall similarities in primary sequence to, and significant differences in molecular and enzymatic properties from, mammalian SULT1B1.

The American bullfrog (Lithobates catesbeianus) is a eurythermal amphibian that is naturally distributed from subarctic to subtropical areas. The tadpoles of this species overwinter, in water, in cold environments. Therefore, they may have adapted to a wide range of temperatures in an active state. To understand the adaptation mechanisms to cope with low or high temperatures, we investigated global epigenetic modifications, histone variants, transcript levels of related genes, and the cellular acetyl coenzyme A (acetyl-CoA) and free CoA (CoA-SH) levels, in the livers of tadpoles collected in summer and winter and of those acclimated to 4 °C and 21 °C. Among epigenetic marks tested, the levels of acetylated histones and the histone variant H2A.Z were influenced by different temperature conditions. Histone acetylation levels were higher in summer than in winter and increased within 3 days of warm acclimation, whereas histone H2A.Z levels were higher in winter than in summer and decreased within 2 weeks of warm acclimation. Transcript analysis revealed that decreased expression of histone H2A.Z in warm acclimation was regulated at the transcriptional level. Acetyl-CoA levels were not correlated with those of the acetylated histones, indicating that cellular acetyl-CoA levels may not directly influence the state of histone acetylation in the tadpole liver. Such epigenetic and metabolic changes in the tadpole liver may contribute to the maintenance of energy balance during seasonal acclimatization and thermal acclimation.

BLAST searches previously carried out against Xenopus genome databases, using the cloned X. laevis cytosolic sulfotransferase 1 (SULT1) cDNA sequence, revealed the presence of more than a dozen members of this gene family. Among them, 11 genes composed of five sets, four pairs and a triplet, were homeologous genes in the X. laevis allotetraploid genome consisting of S- and L-subgenomes (≥83% identity within a set). Phylogenetic and synteny analyses of tetrapod SULT1 genes demonstrated that X. laevis possessed six subfamilies, four of which were related to mammalian SULT1 gene subfamilies, while two were ectothermic vertebrate-specific and amphibian-specific SULT1 gene subfamilies. Five sets of homeologous SULT1 genes were located as a gene cluster, and showed S-subgenome-biased gene expression patterns. Acetylation levels of histone H3 at lysine 9 and H4 were also higher in the homeologous SULT1 genes on the S-subgenome than those on the L-subgenome, however, methylation levels of histone H3 at lysine 9 and DNA methylation levels showed no correlation with their transcript levels. In conclusion, histone modifications such as acetylation may be a key factor that controls the S-subgenome-biased expression of the homeologous SULT1 genes.

BLAST searches against databases for the bullfrog (Rana catesbeiana), using the collectin sequence previously identified in tadpoles, revealed the presence of at least 20 members of the collectin gene family. Phylogenetic analysis demonstrated that the bullfrog possesses expanded gene subfamilies encoding mannose-binding lectin (MBL) and pulmonary surfactant-associated protein D (PSAPD). Two collectins, of 20 kDa (PSAPD1) and 25 kDa (PSAPD6), were purified as a mixture from adult bullfrog plasma using affinity chromatography. These collectins were present as an oligomer of ~400 kDa in their native state, and showed Ca2+-dependent carbohydrate binding with different sugar preferences. Affinity-purified collectins showed weak E. coli agglutination and bactericidal activities, compared with those of plasma. Although both PSAPD1 and PSAPD6 genes were predominantly expressed in the liver, PSAPD1 transcripts were abundant in adults whereas PSAPD6 transcripts were abundant in tadpoles. The findings indicate that two gene subfamilies in the collectin family have diverged structurally, functionally and transcriptionally in the bullfrog. Rapid expansion of the collectin family in bullfrogs may reflect the onset of sub-functionalization of the prototype MBL gene towards tetrapod MBL and PSAPDs, and may be one means of natural adaptation in the innate immune system to various pathogens in both aquatic and terrestrial environments.

Biological activities in ectothermic vertebrates depend to a great extent on ambient temperature. Adapting their biological systems to annual or short-term alterations in temperature may play an important role in thermal resistance or overwintering survival. Using SDS-PAGE and western blot, we examined plasma proteins in bullfrog (Rana catesbeiana) tadpoles that were seasonally acclimatized (winter vs. summer) or thermally acclimated (4 °C vs. 21 °C) and identified two season-responsive proteins. The first, transthyretin (TTR), is a plasma thyroid hormone distributor protein that was abundant in summer, and the second is a protein containing C-type lectin-like domain (CTLD) that was abundant in winter and cold acclimation of 4 weeks. Sequence analysis revealed that the C-terminal carbohydrate recognition domain of this CTLD protein (termed collectin X) was highly similar to those of the collectin family members, which participate in complement activation of the innate immune system; however, it lacked most of collagen-like domain. Among the hepatic genes involved in the thyroid system, ttr and dio3 were up-regulated, whereas thra and thrb were down-regulated, in summer acclimatization or warm acclimation. In contrast, the collectin X gene (colectx), as well as colect10 and colect11 in the collectin family involved in the innate immune system, were down-regulated during warm acclimation, although fcn2 in the ficolin family was up-regulated during summer acclimatization and warm acclimation. These findings indicate that seasonal acclimatization and thermal acclimation differentially affect some components of the thyroid and innate immune systems at protein and transcript levels.

Severe environmental stressors such as low temperatures can affect gene expression by changing epigenetic states. American bullfrog (Rana catesbeiana) can overwinter as tadpoles, which can be active even in winter. However, the molecular mechanisms of epigenetic controls by which the tadpoles acclimate to low temperature are still unclear. In this study, we aimed to clarify the molecular mechanisms of global and gene-specific epigenetic regulations of low-temperature acclimation. We found that the global acetylation was decreased in the liver of bullfrog tadpoles acclimated to low temperature. The amounts of transcripts for two histone acetyltransferases were higher in the liver of tadpoles acclimated to low temperature than in those acclimated to warm temperature, while we observed no significant differences in the amounts of transcripts for histone deacetylases. We also found that the amounts of transcripts and acetylated histones on the specific temperature-responsive genes scd and cyp7a1 whose transcripts were increased and decreased, respectively, in response to low temperature were positively correlated. Cellular acetyl-CoA levels were higher in the liver of tadpoles acclimated to low temperature than in those acclimated to warm temperature. These results contradicted the states of histone acetylation, suggesting that bullfrog tadpoles have different epigenetic mechanisms to modify the histones when compared with those of other organisms such as reptiles and mammals, even though the relationship between the transcript amount and the states of histone acetylation on temperature-responsive genes was similar to that of mammals.

Techniques for analyzing genome-wide expression profiles, such as the microarray technique and next-generation sequencers, have been developed. While these techniques can provide a lot of information about gene expression, selection of genes of interest is complicated because of excessive gene expression data. Thus, many researchers use statistical methods or fold change as screening tools for finding gene sets whose expression is altered between groups, which may result in the loss of important information. In the present study, we aimed to establish a combined method for selecting genes of interest with a small magnitude of alteration in gene expression by coupling with proteome analysis. We used hypercholesterolemic rats to examine the effects of a crude herbal drug on gene expression and proteome profiles. We could not select genes of interest by using standard methods. However, by coupling with proteome analysis, we found several effects of the crude herbal drug on gene expression. Our results suggest that this method would be useful in selecting gene sets with expressions that do not show a large magnitude of alteration., Highlights • Herbal crude drug SJG had mild effects on the gene expression profile. • It was difficult to select genes altered by SJG with conventional methods. • We established analytical method for transcriptome by using proteome experiments. • We identified genes of interest that could not be selected by conventional methods.

Thyroid hormones (THs) play a critical role in amphibian metamorphosis, during which the TH receptor (TR) gene, thrb, is upregulated in a tissue-specific manner. The Xenopus laevis thrb gene has 3 TH response elements (TREs) in the 5' flanking regulatory region and 1 TRE in the exon b region, around which CpG sites are highly distributed. To clarify whether exposure to 3,3',5-triiodothyronine (T3) affects histone and RNA polymerase II (RNAPII) modifications and the level of DNA methylation in the 5' regulatory region, we conducted reverse transcription-quantitative polymerase chain reaction, bisulfite sequencing and chromatin immunoprecipitation assay using X. laevis cultured cells and premetamorphic tadpoles treated with or without 2 nM T3. Exposure to T3 increased the amount of the thrb transcript, in parallel with enhanced histone H4 acetylation and RNAPII recruitment, and probably phosphorylation of RNAPII at serine 5, in the 5' regulatory and exon b regions. However, the 5' regulatory region remained hypermethylated even with exposure to T3, and there was no significant difference in the methylation status between DNAs from T3-untreated and -treated cultured cells or tadpole tissues. Our results demonstrate that exposure to T3 induced euchromatin-associated epigenetic marks by enhancing histone acetylation and RNAPII recruitment, but not by decreasing the level of DNA methylation, in the 5' regulatory region of the X. laevis thrb gene.

Transthyretin (TTR) diverged from an ancestral 5-hydroxyisourate hydrolase (HIUHase) by gene duplication at some early stage of chordate evolution. To clarify how TTR had participated in the thyroid system as an extracellular thyroid hormone (TH) binding protein, TH binding properties of recombinant little skate Leucoraja erinacea TTR was investigated. At the amino acid level, skate TTR showed 37-46% identities with the other vertebrate TTRs. Because the skate TTR had a unique histidine-rich segment in the N-terminal region, it could be purified by Ni-affinity chromatography. The skate TTR was a 46-kDa homotetramer of 14.5kDa subunits, and had one order of magnitude higher affinity for 3,3',5-triiodo-l-thyronine (T3) and some halogenated phenols than for l-thyroxine. However, the skate TTR had no HIUHase activity. Ethylenediaminetetraacetic acid (EDTA) treatment inhibited [(125)I]T3 binding activity whereas the addition of Zn(2+) to the EDTA-treated TTR recovered [(125)I]T3 binding activity in a Zn(2+) concentration-dependent manner. Scatchard analysis revealed the presence of two classes of binding site for T3, with dissociation constants of 0.24 and 17nM. However, the high-affinity sites were completely abolished with 1mM EDTA, whereas the remaining low-affinity sites decreased binding capacity. The number of zinc per TTR was quantified to be 4.5-6.3. Our results suggest that skate TTR has tight Zn(2+)-binding sites, which are essential for T3 binding to at least the high-affinity sites. Zn(2+) binding to the N-terminal histidine-rich segment may play an important role in acquisition or reinforcement of TH binding ability during early evolution of TTR.

To elucidate molecular mechanisms by which the phenolic herbicide ioxynil (IOX) and the brominated flame retardant tetrabromobisphenol A (TBBPA) exert thyroid hormone (TH) disrupting activity, we investigated the effects of the chemicals on the histone and RNA polymerase II (RNAPII) modifications in Xenopus laevis XL58-TRE-Luc cells in direct TH-response genes encoding TH receptor β (Thrb) and TH-induced basic leucine zipper protein (Thibz) using chromatin immunoprecipitation assays. For both the thrb and thibz genes, 3,3',5-triiodothyronine (T3) enhanced the amounts of gene transcripts and increased the amounts of acetylated histone H4 (H4Ac), trimethylated histone H3 lysine 4 (H3K4me3) and phosphorylated RNAPII serine 5 (RNAPIIS5P), epigenetic markers of gene activation at 5' regulatory regions, and the amounts of trimethylated histone H3 lysine 36 (H3K36me3) and phosphorylated RNAPII serine 2 (RNAPIIS2P), epigenetic markers of activation of transcriptional elongation at protein coding regions. Treatment with IOX and TBBPA reduced the amounts of the thrb transcript and suppressed the T3-induced modifications of H3K4me3, RNAPIIS5P, H3K36me3, and RNAPIIS2P. In the thibz gene, IOX and TBBPA did not suppress the T3-induced histone and RNAPII modifications except for H3K36me3 in the TBBPA treatment, despite both chemicals decreasing the T3-induced transcription. Our results demonstrate that IOX and TBBPA affect TH-induced histone and RNAPII modifications, which are involved in early and progressive stages of RNAPII transcriptional elongation, in direct TH-response genes, in somewhat target gene-dependent and chemical-specific manners. Both IOX and TBBPA are likely to influence epigenetically a cascade of TH receptor-mediated gene regulation.

Background Exposure of the American bullfrog Lithobates catesbeianus tadpoles to low temperature affects many biological processes including lipid metabolism and the thyroid hormone (TH) signaling pathway, resulting in arrest of TH-induced metamorphosis. To clarify what molecular events occur in this phenomenon, we investigated the glycerophospholipid and fatty acid (FA) compositions, the activities of mitochondrial enzymes and the transcript levels of related genes in the liver of control (26 °C) and cold-treated (4 °C) tadpoles with or without 5 nM 3,3′,5-triiodothyronine (T3). Results Exposure to T3 decreased the tail height and polyunsaturation of FAs in the glycerophospholipids, and increased plasma glucose levels and transcript levels of primary TH-response genes including TH receptor, and some energy metabolic (cox4, srebp1 and fas) and FA chain elongase genes (elovl3 and elovl5). However, these T3-induced responses were abolished at 4 °C. Exposure to cold temperature enhanced plasma glucose, triglyceride and free FA levels, monounsaturation of FAs, mitochondrial enzymes activities (cytochrome c oxidase and carnitine palmitoyltransferase; U/g liver), with the upregulation of the genes involved in glycogenolysis (pygl), gluconeogenesis (pck1 and g6pc2), FA β-oxidation (acadl), and cholesterol uptake and synthesis (hmgcr, srebp2 and ldlr1), glycerophospholipids synthesis (pcyt1, pcyt2, pemt, and pparg), and FA monounsaturation (scd1) and chain elongation (elovl1 and elovl2). T3 had little effect on the cold-induced changes. Conclusions Our study demonstrated that exposures to T3 and cold temperature exert different effects on lipid metabolism, resulting in changes in the FA composition in glycerophospholipids, and suggests that a cold-induced signal may block TH-signaling pathway around primary TH-response genes. Electronic supplementary material The online version of this article (doi:10.1186/s13578-016-0087-5) contains supplementary material, which is available to authorized users.

Transthyretin (TTR) is a major thyroid hormone-binding protein in the amphibian tadpole whose plasma mRNA and protein levels are altered during metamorphosis. While the temporal and spatial expression patterns and genomic structure of the TTR gene are well studied in higher vertebrates, detailed expression pattern in the extrahepatic tissues, the transcriptional regulation, and the genomic structure have not yet been identified in amphibians. In this study, we attempted to elucidate these mechanisms. Here, we determined the genomic structure of the Xenopus laevis TTR gene including 5'-flanking regions, and examined TTR expression patterns in several tissues. The TTR gene of X. laevis is composed of 4 exons and 3 introns, and the nucleotide sequence of intron 1 is not similar to that previously reported. This suggests that the TTR gene of X. laevis was duplicated and the gene cloned in this study was the other copy of previously reported gene. We also found that TTR was primarily transcribed in the liver of both tadpoles and adults. In the adult liver, TTR transcripts were more abundant in males than females. In higher vertebrates, the expression of TTR is controlled by several transcription factors including forkhead box A2 (FoxA2). However, in the X. laevis liver, FoxA2 expression patterns were not similar to TTR. We also found that exogenous FoxA2 increased the X. laevis TTR promoter-driven luciferase activity. These results suggest that, in amphibian, the expression of TTR is regulated partially by FoxA2, and that another system may exist to control TTR expression.

The sika deer (Cervus nippon) once inhabited the entire Tohoku District, the northeastern part of the main island of Japan. Currently, they are isolated as three discontinuous populations on Mt. Goyo, the Oshika Peninsula, and Kinkazan Island. To assess the genetic diversity and relationships among the sika deer populations in the Tohoku District, we analyzed the mitochondrial DNA D-loop sequences from 177 individuals. We detected a total of five haplotypes. Three haplotypes were present in the population from Mt. Goyo at a haplotype diversity of 0.235 ± 0.061, two haplotypes in the population from the Oshika Peninsula at 0.171 ± 0.064, and only one haplotype was detected in the population from the Kinkazan Island. A significant genetic differentiation was observed among all population pairs. Collectively, our data supports the observed population bottlenecks in the past. Four of the five haplotypes were specific to one of the three populations, whereas only one haplotype was shared between the Mt. Goyo and the Oshika Peninsula populations. This common haplotype may indicate a common ancestral population in the Tohoku District. Conversely, the D-loop haplotypes were completely different among the Kinkazan Island and Oshika Peninsula populations. The lack of a shared haplotype indicates that female gene flow between the two populations is very limited and that the 0.6 km strait acts as a strong barrier.

Ministry of the Directorate General, Higher Education Department of National Education, Indonesia, and the Division of Global Engineering, Osaka University.

We investigated the interaction of 2,4,6-triiodophenol (TIP), a potent thyroid hormone disrupting chemical, with serum proteins from rainbow trout (Onchorhynchus mykiss), bullfrog (Rana catesbeiana), chicken (Gallus gallus), pig (Sus scrofa domesticus), and rat (Rattus norvegicus) using a [(125)I]TIP binding assay, gel filtration chromatography, and native polyacrylamide gel electrophoresis. [(125)I]TIP bound non-specifically to proteins in trout serum, specifically but weakly to proteins in bullfrog serum, and specifically and strongly to proteins in chicken, pig, and rat serum samples. Candidate TIP-binding proteins included lipoproteins (220-320kDa) in trout, albumin in bullfrog, albumin and transthyretin (TTR) in chicken and pig, and TTR in rat. TTR in the chicken, pig, and rat serum samples was responsible for the high-affinity, low-capacity binding sites for TIP (dissociation constant 2.2-3.5×10(-10)M). In contrast, a weak interaction of [(125)I]TIP with tadpole serum proteins accelerated [(125)I]TIP cellular uptake in vitro. Intraperitoneal injection of [(125)I]TIP in tadpoles revealed that the radioactivity was predominantly accumulated in the gallbladder and the kidney. The differences in the molecular and binding properties of TIP binding proteins among vertebrates would affect in part the cellular availability, tissue distribution and clearance of TIP.

A survey of the expression of the transthyretin and thyroxine-binding globulin genes in various species during development provides clues as to how the present thyroid hormone distribution network in extracellular compartments developed during vertebrate evolution. Albumin may be the ‘oldest’ component of the thyroid hormone distribution network as it is found in the plasma of all vertebrates investigated. Subsequent to albumin, transthyretin appeared as the second component in this network during the evolution of vertebrates. The strong expression of transthyretin genes in the liver coincides with the presence of recognition site(s) for liver-enriched transcription factors, such as HNF-3β (Foxa2), in the transthyretin promoter regions of vertebrates. Finally, the addition of thyroxine-binding globulin to this network occurred at postnatal stages in some marsupials and rodents and in perinatal to adult stages in most eutherians. All vertebrates have defined developmental stages when thyroid hormone-dependent transition from larval to juvenile forms occurs. The inclusion of transthyretin and thyroxine-binding globulin in the thyroid hormone distribution network may be correlated with the increased requirement of thyroid hormones for thyroid hormone-dependent tissue remodeling during these stages and/or increased metabolism in thyroid hormone-target tissues with the acquisition of homeothermy.

本論は、アメリカ合衆国内のアフリカ系アメリカ人の歴史に関して考察を加えたものである。まずは、合衆国全体のアフリカ系アメリカ人の歴史についていくつかの事例を挙げ、検討を加えた。次に、広いアメリカ合衆国の一地点(ニューヨーク州ハドソン河中流域渓谷)に拠点を置き、そこから見られるアフリカ系アメリカ人の歴史について論じてみた。最後に、アメリカ合衆国第44代大統領バラク・オバマ氏に関する事例を提示し論を終えた。, In this report, I reviewed the history of African Americans in the United States of America. First, I picked up some of the topics regarding African Americans from an overall viewpoint. Next, I argued some points from a local point of view based on Mid-Hudson Valley. Lastly, I discussed newly-elected President Barack Obama.

To reduce crop damage by Asiatic black bears (Ursus thibetanus), we developed a method to identify individual bears that damaged corn crops based on microsatellite analysis using bear DNA obtained from damaged corn. During summer 2004 in Iwate prefecture, Japan, 99 corn-bite samples were collected, of which 30 (30%) yielded sufficient DNA for 6 complete microsatellite loci. We detected that at least 21 individuals (16 males, 1 female, and 4 of unknown sex) had damaged dent corn in 5 fields. Results enabled individual identification of bears from the samples, but more accurate analysis is needed. Moreover, the sex ratio of nuisance individuals was extremely biased to males compared to that of bears killed through control programs.

本報告は、平成20年度より開始された「質の高い大学教育推進プログラム」に、これまでの本学の国際交流・国際貢献の取組をまとめて応募した申請書の内容を中心としたものである。本学の、オーストラリア研修旅行、アメリカ研修旅行、カンボジア・スタディツアー、新見英語サロン等の実践についての報告である。, This report is based on the application form for the Distinctive University Education Support Program (Good Practice [GP]) of the Ministry of Education, Culture, Sports, Science and Technology of Japan. We have overviewed the Study Tour to Australia, the Study Tour to the United States of America, the Study Tour to Cambodia, Niimi English Salon and so forth.

Effects of pre-strain and heat treatment on shape recovery stress and phase transformation temperature in Ti-Ni-Nb shape memory alloys with various Nb content (6, 9, and 12 mol%) were investigated by tensile testing. The recovery stress of Ti-Ni-Nb alloys increased with increasing the pre-strain and then decreased after reaching the maximum recovery stress of around 450–500 MPa at about 9% pre-strain. Martensitic transformation temperatures (Ms, As, Af) also increased with increasing the applied pre-strain, while the relation between As and prestrain did not depend on the Nb contents and Ni/Ti ratio. Moreover, the recovery stress in the Ti-Ni-Nb alloy heat treated at 673 and 773 K after solution treatment was slightly higher than that in the solution-treated alloy. These behaviors were examined relative to the increased defect density due to pre-straining and the elimination of defects by heat treatment. [doi:10.2320/matertrans.MRA2007266]

This paper describes the effect of heat aging on thermal and mechanical properties of shape memory alloy. The materials used in this study are Ti-Ni-(6-12 at%)Nb shape memory alloy. The tensile tests at 173 K and the heating-cooling tests under constrained strain condition were carried out using the specimens aged at 561 K for between 20 h and 1000 h in normal water chemistry. The martensite start temperature rapidly decreases in the initial short aging time, but there is little further decrease of the martensite start temperature with aging time more than 100 h. The recovery stress gradually increases with aging time, but on the contrary, the aging time of more than 500 h causes reduction of the recovery stress. (doi:10.2320/matertrans.48.439) In order to develop an SMA joint with the prescribed performance, it is necessary to optimize the manufacturing conditions such as the chemical composition, the processing condition and the heat treatment condition of shape memory alloys, that is, the SMA joint should keep up the prescribed function at the storage temperature and reproduce the prescribed function in the normal usage environment. The effects of the Ti/Ni ratio, the Nb concentration, the heat treatment temperature and the processing rate on the mechanical and functional properties were discussed, and the manufacturing conditions of the SMA joint were clarified. The thermal and mechanical properties such as the pre-strain, the recovery strain, the transformation temperature and the recovery stress were also clarified so as to determine the amount of tube expansion of the joint ring. The SMA joint rings are normally used in high-temper- ature water for long-time. In such cases, there is a possibility of the functional property change due to aging. Therefore, in order to maintain the long-term stability of the function of the SMA joint ring and secure the function of the SMA joint ring at lowered environmental temperature, it is necessary to investigate the shape memory property, such as the marten- site start temperature and the recovery stress, of the SMA joint ring exposed to high-temperature water for a long term. In this study, we investigated the thermal and mechanical properties of the joint ring material exposed to high-temper- ature water for a long term, and clarified the effect of the aging time on the function property of the joint ring material, in order to evaluate the performance and the stability of the joint ring in the usage environment of the actual equipment.

This is a Japanese translation of "Guidelines for Relievers, Students and Visitors at Yarra Park" of Yarra Park Childcare Centres in Melbourne, Australia, which Niimi College Early Childhood Education Delegation visit for the study tour every year.

Several Ti-Ni-Nb shape memory alloys (SMAs) with various Nb contents (0� 15 mol%) or Ni/Ti atomic ratios (1:0� 1:1) were tested to investigate the martensitic transformation temperatures and mechanical properties. The martensitic transformation temperatures (Ms, Mf, As and Af ) of the solution-treated Ti-Ni-Nb alloys at 1173 K for 300 seconds with Ni/Ti ratio of 1.0 decrease with increasing the Nb content. These transformation temperatures also depend on the Ni/Ti ratio, heat treatment condition and cold working rate. Furthermore, in the alloy with Nb content of 6 mol% and Ni/Ti atomic ratio being less than 1.05, the fracture stress and fracture strain reached about 1,000 MPa and over 20%, respectively. Based on the obtained results, several processing conditions such as the chemical composition, fabrication process and heat treatment are optimized for the Ti-Ni-Nb SMAs to develop SMA pipe joints. [doi:10.2320/matertrans.48.445]

This study was conducted to evaluate the biocompatibility of titanium-nickel shape memory alloy used as a medical implant material. The authors carried out the following electrochemical corrosion test and in vivo and in vitro biological tests for the alloy and some metal and alloys clinically used previously to compare the intensities concerned with the biological reactions, that is, (1) anodic polarization test for the alloy i na quasi-body fluid, (2) cell proliferation tests for pure titanium (cp Ti), pure nickel (cp Ni), SUS316L stainless steel, titanium-6 mass% aluminium4 mass% vanadium (Ti-6Al-4V), and titanium-55 mass% nickel (Ti-55Ni) by using of L929 fibroblastic cells, (3) Lactate dehydrogenaze (LDH), human interlukin-1� (hIL-1� ), and human tumor necrosis factor-� (hTNF-� ) biochemical assays by using of U937 human macrophages administered the corrosion products of these alloys for the cells, (4) measurement of the mount of excretions of the metallic corrosion products of Ti-55Ni, SUS316L stainless steel, and Ti-6Al-4V with urine and feces injected into the abdomen cavity of Wistar rats, and (5) tissue reaction observations for SUS316L, Ti-55Ni, and cp Ni wires implanted along the femoral bone axis of the rats. The following results were obtained. (1) The pitting corrosion potentials of Ti-55Ni alloy was drastically improved by the aging treatment. (2) In the case of Ti-55Ni alloy, the inflammatory cytokines, hIL-6� and hTNF-� were suppressed to lower levels compared with Ti-6Al-4V alloy. (3) Corrosion products prepared from the titanium alloys were stable in the body. Then it is very hard to eliminate the titanium ions with urine and feces. (4) Ti-55Ni alloy was shown an excellent biocompatibility evaluated by the in vivo implantation test, because of the stable passive film formed on the surface and protected the metal ion release to the surrounding tissue. [doi:10.2320/matertrans.48.352]

Background Amphibians are able to survive for several months without food. However, it is unclear what molecular mechanisms underlie their survival. To characterize the intestinal responses to fasting and refeeding, we investigated morphological, biochemical, transcriptional and epigenetic changes in the intestine from adult male Xenopus laevis. Results Frogs were fed for 22 days, fasted for 22 days, or fasted for 21 days and refed for 1 day. Fasting reduced, and refeeding recovered partially or fully, morphological parameters (wet weight of the intestine, circumference of the epithelial layer and number of troughs in a villus-trough unit), activities of digestive enzymes and plasma biochemical parameters (glucose, triglycerides, cholesterol and free fatty acids). Reverse transcription-quantitative polymerase chain reaction analysis revealed overall suppression of the transcript levels by fasting, with various recovery rates on refeeding. Chromatin immunoprecipitation assays on the selected genes whose transcript levels declined with fasting and recovered quickly with refeeding, showed several euchromatin marks in histone (acetylation and methylation) and RNA polymerase II modifications (phosphorylation) with fasting, and returned to the feeding levels by refeeding. The mRNA levels of these genes responded to fasting and refeeding to greater extents than did the pre-mRNA levels, suggesting the involvement of post-transcriptional regulation. Conclusions Our results demonstrate that the X. laevis intestine may undergo overall metabolic suppression at least at the transcriptional level to save energy during fasting and quickly recovered to moderate nutritional deficiency by refeeding, and suggest that these dietary responses of the intestine are epigenetically and post-transcriptionally regulated. Electronic supplementary material The online version of this article (doi:10.1186/s13578-016-0067-9) contains supplementary material, which is available to authorized users.

In many cases that shape memory alloys are applied to engineering and medical fields, it is necessary to deform them in martensitic phase and after that, to recover them by heating. However, if a slip-deformation occurs, a shape recovery does not occur completely even if heated up above a reverse transformation finish temperature A f . It is reported that transformation temperatures are changed by pre-deformation and in constrained strain condition. Therefore, it is important to investigate the relationship between the pre-deformation and the deformation and transformation characteristics such as the recovery stress, the transformation temperatures and so on. The purpose of this paper is to clarify the influence of the pre-deformation on the recovery strain, the recovery stress and the transformation temperatures in a Ti-Ni shape memory alloy. The material used in this study is Ti-50 at%Ni alloy annealed at 1103 K for 60 s. The variation of the recovery strain, the recovery stress and the transformation temperatures by the pre-straining are investigated experimentally, and also the variation of the transformation and deformation characteristics by the pre-straining is discussed in relation to the volume fraction of slip-deformed martensite.

Attempts have been made to develop new types of seismic devices using shape memory alloys. They are a single-stage bellows which are processed from thin-walled tubes by employing the rubber bulge method and then are annealed at 400°C for the shape-memory treatment. As strain distribution is induced on the bulged part due to the process, it is significant to know the effects of pre-strain and the subsequent heat-treatment on the mechanical properties of the material for tube when designing the bellows shapes for the seismic structures. Thus, tensile tests and thermal analysis were conducted before and after the heat treatment on rectangular specimens cut from the tubes. In this paper, the oxidization method was first attempted to observe distinctively both regions of the stress induced martensite (SIM) transformation and twin deformation generated while applying strain to the specimens. It became clear that the micro-structure in the SIM area had a changed R phase from the austenite phase at room temperature after being annealed at 400°C. From the experimental and analytical results for the specimens, the mechanical behavior was classified broadly into two conditions as follows: (1) the mechanical behavior can be formulated on the basis of a series-model consisting of areas of both R phase and austenite considering the area-ratio of these phases until the SIM transformation has expanded over the whole specimen, and (2) after that, the mechanical behavior can be formulated using the exponential function for the applied strain as a parameter.

The effects of Sn content and aging conditions on superelasticity in Ti-Mo-Sn alloys were investigated. Martensitic transformation temperature decreased with an increasing of Sn content. A large superelastic strain of 3.0% was obtained in a solution-treated Ti-5 mol%Mo-5 mol%Sn alloy in the tensile test. The superelasticity in the Ti-5 mol%Mo-5 mol%Sn at room temperature was improved by aging at 873 K for short periods between 180 and 420 s. A specimen aged at 873 K for 300s exhibited superelasticity with a recovery strain of 3.5% in the tensile test. A recovery strain of 3.0% was consistently achieved in cyclic tensile deformations.

本報告は、旧大佐町とアメリカ合衆国ニューヨーク州ニューパルツ・ヴィレッジの姉妹都市交流に積極的に関わってきたニューパルツ国際交流協会の13名の会員に対するアンケート結果を集約し、この姉妹都市交流がニューパルツ・ヴィレッジの市民にどのような影響を与えたかについてまとめたものである。回答者がニューパルツ国際交流協会で積極的に姉妹都市交流に関わってきた市民達であることもあり、姉妹都市交流の経験が彼らの人生および生活に与えた肯定的影響について多く記述されている。, This report deals with the comments for the questionnaire on the sister city relationship between New Paltz Village, New York, USA and Osa Town, Okayama, Japan. The questionnaire was done to 13 members of New Paltz International Exchange Association. The respondents were asked about what kind of sister city exchanges they had experienced, if the exchange has changed their life in any way, what kind of exchanges they think we need in the future, and so forth. This is to verify the importance of sister city relationship and exchanges.

The modeling of the transformation and deformation behavior of a shape memory alloy has been investigated by many researchers. However, there are few reports that investigate plastic deformation of shape memory alloys. To design an actual product, the modeling in consideration of plastic deformation is indispensable. In this work, plastic deformation after pre-deformation is investigated using the volume fraction of slip-deformed martensite. New kinetics and constitutive equations are proposed for the reverse transformation process. The material constants in the proposed equations are determined from the results of tensile and heating/cooling tests on Ti–50 at%Ni alloy. The calculated results describe well the deformation and transformation behavior affected by pre-strain.

The effect of the relative grain size d/D (d: grain size, D: wire diameter) on stress–strain characteristics was investigated in Cu–Al–Mn-based shape memory alloy (SMA) wires. The yield stress (σy), the work-hardening rate after yielding (dσPE/de) and the stress hysteresis (Δσ) in the wires with a random texture decrease with increasing d/D. The transformation strain (eTS) and the maximum pseudoelastic strain ( e PE MAX ) increase with increasing d/D. The effect of grain size on pseudoelastic behaviors can be clarified from the volume fraction of three-dimensionally constrained grains and the σy, dσPE/de and Δσ increase proportionally with increasing (1 − (d/D))2 while the eTS decreases proportionally with increasing (1 − (d/D))2. Consequently, the effect of grain size on the pseudoelastic behaviors can be expressed using the Taylor and inverse Schmid factors. The σy and the eTS for wires with a 〈1 1 0〉 fiber texture are larger and smaller than those for wires with a random texture, respectively.

We investigated the effects of phenolic and phenol compounds on 3,3',5-L- 1 2 5 I-triiodothyronine ( 1 2 5 I-T 3 ) binding to purified Xenopus laevis transthyretin (xTTR) and to the ligand-binding domain of X. laevis thyroidhormone receptor β (xTR LBD), on T 3 -induced metamorphosis in X. laevis tadpoles and on the induction of T 3 -dependent reporter gene in a X. laevis cell line. Of the halogenated phenolic and phenol compounds tested, 3,3',5-trichlorobisphenol A and 2,4,6-triiodophenol, respectively, were the most potent competitors of 1 2 5 I-T 3 binding to both xTTR and xTR LBD. Most of the halogenated compounds had stronger interactions with xTTR than with xTR LBD. Generally, chlorinated derivatives with a greater degree of chlorination were more efficient competitors of T 3 binding to xTTR and xTR LBD. Structures with a halogen in either ortho position or in both ortho positions, with respect to the hydroxy group, were more efficient competitors. 3,3',5-Trichlorobisphenol A and 2,4,6-triiodophenol acted as T 3 antagonists in the X. laevis tadpole metamorphosis assay. Interestingly, o-t-butylphenol and 2-isopropylphenol, for which xTTR and xTR LBD had weak or no significant affinity, showed T 3 antagonist activity in the metamorphosis assay. T 3 antagonist activities of all these chemicals except for o-t-butylphenol were verified by T 3 -dependent reporter gene assay. Our results suggest that some phenolic and phenol compounds target the process of T 3 binding to xTTR and xTR and/or an unknown process, and that they interfere with the intracellular T 3 signaling pathway.

In many cases that shape memory alloys are applied to engineering and medical fields, it is necessary to deform them in martensitic phase and after that, to recover them by heating. However, if a slip-deformation occurs, a shape recovery does not occur completely even if heated up above a reverse transformation finish temperature A f . It is reported that transformation temperatures are changed by pre-deformation and in constrained strain condition. Therefore, it is important to investigate the relationship between the pre-deformation and the deformation and transformation characteristics such as the recovery stress, the transformation temperatures and so on. The purpose of this paper is to clarify the influence of the pre-deformation on the recovery strain, the recovery stress and the transformation temperatures in a Ti-Ni shape memory alloy. The material used in this study is Ti-50 at%Ni alloy annealed at 1103 K for 60 s. The variation of the recovery strain, the recovery stress and the transformation temperatures by the pre-straining are investigated experimentally, and also the variation of the transformation and deformation characteristics by the pre-straining is discussed in relation to the volume fraction of slip-deformed martensite.

This paper deals with the bulge process for forming the single-stage bellows of TiNi shape memory alloys, which is proposed as a new type of seismic applications, and especially considering the material's special behavior. Thin walled tubes with 20% cold work, whose composition is Ti51.0 at% Ni, were prepared. First they are appropriately heat-treated and then the rubber bulge process is introduced for the tubes under the condition of austenite phase at room temperature. Displacement control method is adapted to the process. Theoretical prediction of change in outer diameter of the tube on compression is derived, and modified taking into account the progress of the stress-induced martensite transformation on tube's surface by observing the detachment of the oxide layer of the surface. Finally theoretical relationship between compressive displacement and the outer diameter of the tube, which is the most inportant for the design of the bellows shape, is cleared.

We examined possible molecular mechanisms for the low-temperature arrest of T3-induced Rana catesbeiana metamorphosis. Scatchard plots revealed that the ratios of maximum binding capacity/dissociation constant for high-affinity sites of tadpole serum proteins for T3 at 20 and 28 C was 3.3-4.6 times less than that at 4 C, due to the decrease in maximum binding capacity values. Kinetic studies of T3 uptake into tadpole red blood cells demonstrated that the ratio of maximum uptake rate/Michaelis constant at 23 C was approximately 13 times greater than that at 4 C. The process of intracellular transport of T3 into the nucleus was not arrested at 4 C. The ratio of T3 incorporated into nuclei to that taken up into red blood cells was not significantly different at 4, 20, and 28 C, indicating the absence of temperature-sensitive sites in this process. T3 binding to the T3 receptors alpha and beta were not temperature sensitive at least at 4 and 20 C. Transcription of the tr genes, early primary T3 response genes, was activated by 10 nM T3 at 20 and 28 C but was barely detected at 4 C. These results indicate that the major molecular event causing the low-temperature arrest of amphibian metamorphosis occurs after T3 entry into the nucleus but before or during the transcriptional activation of the tr genes. Plasma proteins binding T3 and the cellular thyroid hormone uptake system on the plasma membrane may contribute to the slowing of the incorporation of T3 into nucleus at 4 C by decreasing the uptake velocity of T3.

長崎市とセントポール市との姉妹都市交流は1955年に始まる最初の日米姉妹都市交流であり、間もなく2005年で50周年を迎える。本稿では、この50年間どのような姉妹都市交流が行われてきたかを、主に長崎市における、インタビュー、訪問、資料収集から概観し、今後の展望について述べる。, The sister city relationship between Nagasaki City, Japan and Saint Paul City, Minnesota, U.S.A. started in 1955. It is the first city affiliation between a Japanese city and a U.S. city, and it has the 50th anniversary in 2005. The author reports on the contents of the intermunicipal exchanges for the 50 years after interviewing key persons, visiting related places and collecting materials in Nagasaki. The author also touches upon future perspectives of the exchange.