著者
Azusa Takahashi Hisae Shimizu Yukako Okazaki Hirohide Sakaguchi Toshio Taira Takashi Suzuki Hideyuki Chiji
出版者
Japan Oil Chemists' Society
雑誌
Journal of Oleo Science (ISSN:13458957)
巻号頁・発行日
vol.64, no.12, pp.1243-1250, 2015 (Released:2015-12-01)
参考文献数
34
被引用文献数
5 38

Aronia fruits (chokeberry: Aronia melanocarpa E.) containing phenolic phytochemicals, such as cyanidin 3-glycosides and chlorogenic acid, have attracted considerable attention because of their potential human health benefits in humans including antioxidant activities and ability to improved vision. In the present study, the effects of anthocyanin-rich phytochemicals from aronia fruits (aronia phytochemicals) on visceral fat accumulation and fasting hyperglycemia were examined in rats fed a high-fat diet (Experiment 1). Total visceral fat mass was significantly lower in rats fed aronia phytochemicals than that in both the control group and bilberry phytochemicals-supplemented rats (p < 0.05). Moreover, perirenal and epididymal adipose tissue mass in rats fed aronia phytochemicals was significantly lower than that in both the control and bilberry phytochemicals group. Additionally, the mesenteric adipose tissue mass in aronia phytochemicals-fed rats was significantly low (p < 0.05). Furthermore, the fasting blood glucose levels significantly decreased in rats fed aronia phytochemicals for 4 weeks compared to that in the control rats (p < 0.05). Therefore, we investigated the effects of phytochemicals on postprandial hyperlipidemia after corn oil loading in rats, pancreatic lipase activity in vitro, and the plasma glycemic response after sucrose loading in order to elucidate the preventive factor of aronia phytochemical on visceral fat accumulation. In the oral corn oil tolerance tests (Experiment 2), aronia phytochemicals significantly inhibited the increases in plasma triglyceride levels, with a half-maximal inhibitory concentration (IC50) of 1.50 mg/mL. However, the inhibitory activity was similar to that of bilberry and tea catechins. In the sucrose tolerance tests (Experiment 3), aronia phytochemicals also significantly inhibited the increases in blood glucose levels that were observed in the control animals (p < 0.05). These results suggest that anthocyanin-rich phytochemicals in aronia fruits suppress visceral fat accumulation and hyperglycemia by inhibiting pancreatic lipase activity and/or intestinal lipid absorption.
著者
Jiro Osaka Haruka Yasuda Yusuke Watanuki Yuya Kato Yohei Nitta Atsushi Sugie Makoto Sato Takashi Suzuki
出版者
The Genetics Society of Japan
雑誌
Genes & Genetic Systems (ISSN:13417568)
巻号頁・発行日
vol.97, no.6, pp.297-309, 2022-12-01 (Released:2023-04-18)
参考文献数
35
被引用文献数
3

Neural activity-dependent synaptic plasticity is an important physiological phenomenon underlying environmental adaptation, memory and learning. However, its molecular basis, especially in presynaptic neurons, is not well understood. Previous studies have shown that the number of presynaptic active zones in the Drosophila melanogaster photoreceptor R8 is reversibly changed in an activity-dependent manner. During reversible synaptic changes, both synaptic disassembly and assembly processes were observed. Although we have established a paradigm for screening molecules involved in synaptic stability and several genes have been identified, genes involved in stimulus-dependent synaptic assembly are still elusive. Therefore, the aim of this study was to identify genes regulating stimulus-dependent synaptic assembly in Drosophila using an automated synapse quantification system. To this end, we performed RNAi screening against 300 memory-defective, synapse-related or transmembrane molecules in photoreceptor R8 neurons. Candidate genes were narrowed down to 27 genes in the first screen using presynaptic protein aggregation as a sign of synaptic disassembly. In the second screen, we directly quantified the decreasing synapse number using a GFP-tagged presynaptic protein marker. We utilized custom-made image analysis software, which automatically locates synapses and counts their number along individual R8 axons, and identified cirl as a candidate gene responsible for synaptic assembly. Finally, we present a new model of stimulus-dependent synaptic assembly through the interaction of cirl and its possible ligand, ten-a. This study demonstrates the feasibility of using the automated synapse quantification system to explore activity-dependent synaptic plasticity in Drosophila R8 photoreceptors in order to identify molecules involved in stimulus-dependent synaptic assembly.
著者
Hinata Kawamura Satoko Hakeda-Suzuki Takashi Suzuki
出版者
The Genetics Society of Japan
雑誌
Genes & Genetic Systems (ISSN:13417568)
巻号頁・発行日
vol.95, no.5, pp.235-247, 2020-10-01 (Released:2021-02-11)
参考文献数
49
被引用文献数
6

Neural activity contributes to synaptic regulation in sensory systems, which allows organisms to adjust to changing environments. However, little is known about how synaptic molecular components are regulated to achieve activity-dependent plasticity at central synapses. Previous studies have shown that following prolonged exposure to natural ambient light, the presynaptic active zone (AZ), an area associated with presynaptic neurotransmitter release in Drosophila photoreceptors, undergoes reversible remodeling. Other studies suggest that the secretory protein Wingless (Wg; an ortholog of Wnt-1) can mediate communication between synaptic cells to achieve synaptic remodeling. However, the source of Wg and the mechanism of Wg signal modulation by neuronal activity remained unclear. Here, we found that Wg secreted from glial cells regulates synaptic remodeling in photoreceptors. In addition, antibody staining revealed that Wg changes its localization depending on light conditions. Although Wg is secreted from glial cells, Wg appeared inside photoreceptor axons when flies were kept under light conditions, suggesting that an increase in neuronal activity causes Wg internalization into photoreceptors by endocytosis. Indeed, by blocking endocytosis in photoreceptors, the localization of Wg in photoreceptors disappeared. Interestingly, Wg accumulation was higher in axons with disassembled AZ structure than in axons whose AZ structure was stabilized at the single-cell level, indicating that Wg endocytosis may trigger AZ disassembly. Furthermore, when we genetically activated Wg signaling, Wg accumulation in photoreceptors decreased. Conversely, when we suppressed Wg signaling there was an increase in Wg accumulation. Through RNAi screening of Ca2+-binding proteins in photoreceptors, we found that Calcineurin is a key molecule that triggers Wg endocytosis. Overall, we propose that Wg signaling is regulated by a negative feedback loop driven by Wg endocytosis. The increase in neuronal activity is transmitted via calcium signaling, which leads to a decrease in Wg signaling and thereby promotes presynaptic remodeling.
著者
Tomohiro Araki Jiro Osaka Yuya Kato Mai Shimozono Hinata Kawamura Riku Iwanaga Satoko Hakeda-Suzuki Takashi Suzuki
出版者
The Genetics Society of Japan
雑誌
Genes & Genetic Systems (ISSN:13417568)
巻号頁・発行日
pp.19-00066, (Released:2020-06-04)
参考文献数
25
被引用文献数
4

In many animals, neural activity contributes to the adaptive refinement of synaptic properties, such as firing frequency and the number of synapses, for learning, memorizing and adapting for survival. However, the molecular mechanisms underlying such activity-dependent synaptic remodeling remain largely unknown. In the synapses of Drosophila melanogaster, the presynaptic active zone (AZ) forms a T-shaped presynaptic density comprising AZ proteins, including Bruchpilot (Brp). In a previous study, we found that the signal from a fusion protein molecular marker consisting of Brp and mCherry becomes diffuse under continuous light over three days (LL), reflecting disassembly of the AZ, while remaining punctate under continuous darkness. To identify the molecular players controlling this synaptic remodeling, we used the fusion protein molecular marker and performed RNAi screening against 208 neuron-related transmembrane genes that are highly expressed in the Drosophila visual system. Second analyses using the STaR (synaptic tagging with recombination) technique, which showed a decrease in synapse number under the LL condition, and subsequent mutant and overexpression analysis confirmed that five genes are involved in the activity-dependent AZ disassembly. This work demonstrates the feasibility of identifying genes involved in activity-dependent synaptic remodeling in Drosophila, and also provides unexpected insight into the molecular mechanisms involved in cholesterol metabolism and biosynthesis of the insect molting hormone ecdysone.
著者
佐藤 進;Susumu SATO 鈴木 貴士;Takashi SUZUKI 川尻 達也;Tatsuya KAWASHIRI 山口 真史;Masafumi YAMAGUCHI
出版者
金沢工業大学
雑誌
工学教育研究;KIT progress (ISSN:13421662)
巻号頁・発行日
no.24, pp.53-62, 2016

新入生に対し、大学に対する不本意感および学業へのつまずき感に関する調査を2回(入学当初および1年終了時)実施し、追跡が可能であった1,411 名を対象に、その特徴を検討した。1年次春の時点で大学への不本意感は約1割、学業へのつまずき感は約2割の学生が有していた。これらの割合は冬の調査時点でも同等であったが、構成している学生の約半数は入れ替わっていた。大学への不本意感が春から冬にかけて生じた学生は、受験の失敗に対する思いが再燃し、自身の理想とする大学像とのギャップや授業内容・カリキュラムに対する不満が高まっていた。同様に、学業へのつまずき感が春から冬にかけて生じた学生は、課題遂行の困難さや学業への不向きさを自覚しながら、単位取得・留年・卒業への不安が高まる傾向にあった。;This study researched the characteristics of the university freshmen who are unwilling to join the university and who feel anxiety about academic learning for 1,411 university freshmen. A biannual survey on the unwillingness to join the university community and anxiety about academic learning was conducted in spring (the end of May) and winter (December to February). About 10 % of the freshmen were unwilling to join the university, and about 20% of them had anxiety about academic learning in the spring. Although these percentages did not change in the winter, half of the persons with the unwillingness or anxiety was replaced by another persons. The students, who were unwilling to join the university during the spring and winter months, reignite a sense offailing to enter university, and more dissatisfied with academic curriculum or lesson contents. Similarly, the students, who feel anxiety about academic learning during the spring and winter months, realized difficulty to class assignments and unfit for academic learning, and increased anxiety about acquisition of academic credit, graduation, and staying back a year.
著者
Tomoo Maeda Ayumi Watanabe Wambrauw Daniel Zadrak Sachiyo Osanai Kazushige Honda Satoshi Oku Hanako Shimura Takashi Suzuki Atsushi Yamasaki Yosuke Okabe Keiji Ueno Shuichi Onodera
出版者
一般社団法人 園芸学会
雑誌
The Horticulture Journal (ISSN:21890102)
巻号頁・発行日
pp.OKD-068, (Released:2017-03-29)
被引用文献数
10

Onions (Allium cepa L.) accumulate fructo-oligosaccharides (FOSs) as storage carbohydrates. FOSs exist in various chemical forms with different degrees of polymerization (DP) and chemical bonding states. Therefore, it is difficult to determine the precise FOS composition and quantity of each type of FOS. The objective of this study was to analyze the varietal differences in FOS composition and relative quantities among onion cultivars grown by spring-sown cultivation in Hirosaki City, Japan, using a high performance liquid chromatography (HPLC) system equipped with an evaporative light scattering detector (ELSD). FOS compositions of a number of varieties, as determined by HPLC/ELSD, were confirmed using matrix-assisted laser desorption/ionization time-of-flight -mass spectrometry (MALDI-TOF MS). Sugar and FOS analyses revealed distinct patterns of sugar and FOS accumulation, which led to categorization of the tested varieties into three types: (1) those with a relatively high overall quantity of FOSs and with a higher DP (DP3 to over DP9); (2) those containing mainly monosaccharides (fructose and glucose), disaccharide (sucrose), and low amounts of FOSs; and (3) those with a carbohydrate content that was intermediate compared to that of the other two types. Measurements of enzyme activities suggested that varietal differences in FOS composition are the result of differences in enzyme activities associated with the FOS biosynthetic and biodegradation pathways.
著者
Sangchai Yingsakmongkon Daisei Miyamoto Nongluk Sriwilaijaroen Kimie Fujita Kosai Matsumoto Wipawee Jampangern Hiroaki Hiramatsu Chao-Tan Guo Toshihiko Sawada Tadanobu Takahashi Kazuya Hidari Takashi Suzuki Morihiro Ito Yasuhiko Ito Yasuo Suzuki
出版者
The Pharmaceutical Society of Japan
雑誌
Biological and Pharmaceutical Bulletin (ISSN:09186158)
巻号頁・発行日
vol.31, no.3, pp.511-515, 2008-03-01 (Released:2008-03-01)
参考文献数
30
被引用文献数
42 46

Using a plaque reduction assay, treatment of human influenza A viruses with the fruit-juice concentrate of Japanese plum (Prunus mume SIEB. et ZUCC) showed strong in vitro anti-influenza activity against human influenza A viruses before viral adsorption, but not after viral adsorption, with 50% inhibitory concentration (IC50) values against A/PR/8/34 (H1N1) virus, A/Aichi/2/68 (H3N2) virus and A/Memphis/1/71 (H3N2) virus of 6.35±0.17, 2.84±1.98 and 0.53±0.10 μg/ml, respectively. The plum-juice concentrate exhibited hemagglutination activity toward guinea pig erythrocytes. Its hemagglutination activity was inhibited by the monosaccharide N-acetylneuraminic acid and a sialoglycoprotein (fetuin), but not by the other tested monosaccharides (mannose, galactose, glucose and N-acetylglucosamine), suggesting the presence of a lectin-like molecule(s) in the Japanese plum-juice concentrate. Our findings suggest that the fruit-juice concentrate of Japanese plum may prevent and reduce infection with human influenza A virus, possibly via inhibition of viral hemagglutinin attachment to host cell surfaces by its lectin-like activity.
著者
Azliza Mad Anuar Akira Minami Hiroshi Matsushita Kanako Ogino Kosei Fujita Hatsune Nakao Shota Kimura Vikineswary Sabaratnam Kaoru Umehara Yuuki Kurebayashi Tadanobu Takahashi Hiroaki Kanazawa Akihiko Wakatsuki Takashi Suzuki Hideyuki Takeuchi
出版者
The Pharmaceutical Society of Japan
雑誌
Biological and Pharmaceutical Bulletin (ISSN:09186158)
巻号頁・発行日
vol.45, no.10, pp.1438-1443, 2022-10-01 (Released:2022-10-01)
参考文献数
59

Estrogen deficiency during menopause causes a variety of neurological symptoms, including depression. The edible Lion’s Mane mushroom, Hericium erinaceus (Bull.: Fr.) Pers. (HE), is a medicinal mushroom that has the potential for a neuroprotective effect and ameliorating neurological diseases, such as depression, anxiety, and neurodegenerative diseases. HE contains phytoestrogens, including daidzein and genistein. However, the ameliorating effect of HE on menopausal symptoms is not well understood. Here we investigated the impact of methanol extract of the HE fruiting body on depressive-like behavior in postmenopausal model rats. The activation of estrogen receptor alpha (ERα) causes body weight loss and uterine weight gain. Body weight gain and uterine weight loss by estrogen deficiency in ovariectomized (OVX) rats were reversed with 17β-estradiol (E2) but not with HE. Thus, the phytoestrogens in HE may hardly activate ERα. Estrogen receptor beta (ERβ) is expressed in the brain, and activation of ERβ ameliorates menopausal depressive symptoms. Notably, depressive-like behavior in OVX rats evaluated in forced swim test was reduced by administration of not only E2 but also HE for 92 d. Long-term activation of ERα increases the risk of breast and uterine cancers. HE, therefore, may be effective in treating menopausal depression without the risk of carcinogenesis caused by ERα activation.
著者
Toshihiro Akihisa Keiichi Tabata Norihiro Banno Harukuni Tokuda Reiko Nishihara Yuji Nakamura Yumiko Kimura Ken Yasukawa Takashi Suzuki
出版者
The Pharmaceutical Society of Japan
雑誌
Biological and Pharmaceutical Bulletin (ISSN:09186158)
巻号頁・発行日
vol.29, no.9, pp.1976-1979, 2006 (Released:2006-09-01)
参考文献数
20
被引用文献数
46 57

Fifteen triterpene acids, viz., seven of the β-boswellic acids (ursane-type) (1—7), two of the α-boswellic acids (oleanane-type) (8, 9), two of the lupeolic acids (lupane-type) (10, 11), and four of the tirucallane-type (12—14, 16), and two cembrane-type diterpenes (17, 18), isolated from the MeOH extract of the resin of Boswellia carteri (Burseraceae), together with a triterpene acid 15 (the acetyl derivative of 14), were examined for their inhibitory effects on the induction of Epstein–Barr virus early antigen (EBV-EA) by 12-O-tetradecanoylphorbol-13-acetate (TPA) in Raji cells and on activation of (±)-(E)-methyl-2[(E)-hydroxyimino]-5-nitro-6-methoxy-3-hexemide (NOR 1), a nitrogen oxide (NO) donor, and cytotoxic activities against three human neuroblastoma cell lines, IMR-32, NB-39, and SK-N-SH in vitro. On evaluation against the EBV-EA activation induced by TPA, seven compounds, 2, 10, 11, and 13—16, showed potent inhibitory effects on EBV-EA induction. Upon evaluation against activation of NOR 1, five compounds, 7, 13, and 14—16, showed potent inhibitory effects. Further, fifteen compounds, 1—7, 9—11, 13—15, 17, and 18, exhibited potent cytotoxic activities with IC50 values of 4.1—82.4 μM against all of the three human neuroblastoma cells tested.
著者
Toshihiro Akihisa Taisuke Noto Akitomo Takahashi Yukiko Fujita Norihiro Banno Harukuni Tokuda Kazuo Koike Takashi Suzuki Ken Yasukawa Yumiko Kimura
出版者
Japan Oil Chemists' Society
雑誌
Journal of Oleo Science (ISSN:13458957)
巻号頁・発行日
vol.58, no.11, pp.581-594, 2009 (Released:2009-10-20)
参考文献数
35
被引用文献数
52 69

Thirty-one nortriterpenoids, including 28 limonoids (1-28) and 3 degraded limonoids (29-31), and one diterpenoid (32), were isolated from the seed extract of Azadirachta indica (neem). Among these, six were new compounds and their structures were established to be 15-hydroxyazadiradione (3), 7-benzoyl-17-hydroxynimbocinol (5), 23-deoxyazadironolide (12), limocin E (13), 23-epilimocin E (14), and 7α-acetoxy-3-oxoisocopala-1,13-dien-15-oic acid (32). Upon evaluation of compounds 1-32 on the melanogenesis in the B16 melanoma cells, five compounds, 20, 26, 27, 29, and 31, exhibited marked inhibitory effect (74-91% reduction of melanin content at 25 μg/mL) with no or almost no toxicity to the cells. Seven compounds, 1, 6, 9, 10, 18, 20, and 26, on evaluation for their inhibitory effect against 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced inflammation (1 μg/ear) in mice, exhibited, except for compound 26, marked anti-inflammatory activity (ID50 values 0.09-0.26 mg/ear). In addition, all of the 32 compounds exhibited moderate or potent inhibitory effects (IC50 values of 230-501 mol ratio/32 pmol TPA) against the Epstein-Barr virus early antigen (EBV-EA) activation induced by TPA. Furthermore, on evaluation of azadirachtin B (21) for its anti-tumor-initiating activity on the two-stage carcinogenesis of mouse skin tumor induced by peroxynitrite (ONOO-; PN) as an initiator and TPA as a promoter, this exhibited marked inhibitory activity.
著者
Satoshi SUZUKI Hiroyoshi TSUBOCHI Andrew DARNEL Takashi SUZUKI Hironobu SASANO Zigmunt S. KROZOWSKI Takashi KONDO
出版者
The Japan Endocrine Society
雑誌
Endocrine Journal (ISSN:09188959)
巻号頁・発行日
vol.50, no.4, pp.445-451, 2003 (Released:2003-09-11)
参考文献数
31
被引用文献数
7 13

11β-Hydroxysteroid dehydrogenase type 1 (11β-HSD1) behaves predominantly as an oxoreductase converting the receptor-inactive glucocorticoids to their active forms in vivo, while the type 2 isoform (11β-HSD2) possesses only dehydrogenase activity and inactivates cortisol in human or corticosterone in rat. We determined enzyme activity of 11β-HSD in rat lungs from fetus to adult, and examined whether 11β-HSD1 exists in alveolar type II cells, the most important site for the synthesis of pulmonary surfactant in mature lungs, by immunohistochemistry and reverse transcription-polymerase chain reaction (RT-PCR). Enzyme activity of 11β-HSD1 and 2 in lung tissue homogenate were determined as NADP+- and NAD+-dependent conversion of corticosterone to 11-dehydrocorticosterone, respectively. We found that 11β-HSD1 activity was increased progressively from 21 days gestation to 7 weeks after birth. 11 β-HSD2 activity was significantly lower than that of 11β-HSD1 throughout gestation and after birth. Immunoreactivity for 11β-HSD1 was detected in the cytoplasm of the cells in the alveolar region of adult rats. Some of these expressing 11β-HSD1 were considered to be alveolar type II cells, because of their cuboid shape and localization at the corner of the alveoli. RT-PCR demonstrated 11 β-HSD1 mRNA in isolated alveolar type II cells. Our results suggest that alveolar type II cells enhance intracellular glucocorticoid availability via 11β-HSD1. 11β-HSD1 in alveolar type II cells is thought of as an autocrine amplifier of glucocorticoid action in the lung.
著者
Tadanobu Takahashi Takashi Suzuki
出版者
The Pharmaceutical Society of Japan
雑誌
Biological and Pharmaceutical Bulletin (ISSN:09186158)
巻号頁・発行日
vol.38, no.6, pp.817-826, 2015-06-01 (Released:2015-06-01)
参考文献数
69
被引用文献数
3 11

The spike glycoprotein neuraminidase (NA) of influenza A virus (IAV) has sialidase activity that cleaves the terminal sialic acids (viral receptors) from oligosaccharide chains of glycoconjugates. A new antigenicity of viral surface glycoproteins for humans has pandemic potential. We found “low-pH stability of sialidase activity” in NA. The low-pH stability can maintain sialidase activity under acidic conditions of pH 4–5. For human IAVs, NAs of all pandemic viruses were low-pH-stable, whereas those of almost all human seasonal viruses were not. The low-pH stability was dependent on amino acid residues near the active site, the calcium ion-binding site, and the subunit interfaces of the NA homotetramer, suggesting effects of the active site and the homotetramer on structural stability. IAVs with the low-pH-stable NA showed much higher virus replication rates than those of IAVs with low-pH-unstable NA, which was correlated with maintenance of sialidase activity under an endocytic pathway of the viral cell entry mechanism, indicating contribution of low-pH stability to high replication rates of pandemic viruses. The low-pH-stable NA of the 1968 H3N2 pandemic virus was derived from the low-pH-stable NA of H2N2 human seasonal virus, one of two types classified by both low-pH stability in N2 NA and a phylogenetic tree of N2 NA genes. The 2009 H1N1 pandemic virus acquired low-pH-stable NA by two amino acid substitutions at the early stage of the 2009 pandemic. It is thought that low-pH stability contributes to infection spread in a pandemic through enhancement of virus replication.
著者
Yutaka Jitsuyama Ayane Ichiki Ryosuke Ide Hanako Shimura Takashi Suzuki
出版者
The Japanese Society for Horticultural Science
雑誌
The Horticulture Journal (ISSN:21890102)
巻号頁・発行日
pp.UTD-008, (Released:2018-12-26)
被引用文献数
3

An excess or lack of soil moisture are significant abiotic stresses that reduce the average yield for vegetable crops worldwide. The responses of ‘Natsunoshun’, a processing tomato cultivar, to water stress at three growth stages, first flower differentiation, first flowering, and fruit development, were investigated over a two-year period. The year effect on yield was not significant; however, the growth stage and the type of water stress at a particular growth stage affected yield significantly. Either an excess or lack of soil moisture after the first flowering stage were significant in reducing yield. The decrease was related to the average weight of the fruit rather than the number per plant. Under dry conditions, fruit number was the same as control plants, but there was a decrease in the reddish mature fruit ratio. On the other hand, under wet conditions plant biomass decreased, especially in the roots, even if there was a transition from wet to dry conditions. We conclude that excessive soil moisture during the first flowering stage produces slower CGR and decreased biomass in the roots, which we believe is the reason for the yield decline.
著者
Takashi SUZUKI Narumi YAMAMOTO Hirotaka KONDO Hisashi SHIBUYA
出版者
JAPANESE SOCIETY OF VETERINARY SCIENCE
雑誌
Journal of Veterinary Medical Science (ISSN:09167250)
巻号頁・発行日
pp.18-0382, (Released:2018-09-19)

The neoplastic mass developed in the left flank of a Border Collie dog. The tumor was resected surgically and evaluated histologically and immunohistochemically. Histologically a moderate number of spindle cells were proliferated with staghorn, placentoid, and myxoid growth patterns and a lack of perivascular whirling. Immunohistochemically, the tumor cells were positive to vimentin, laminin, S-100 protein, CD34 and CD117 antibodies. They were negative to cytokeratin AE1/3, desmin, α-SMA and calponin antibodies. Endothelial cells of the staghorn channels were positive for vWF antibody. The present case was diagnosed as spindle cell tumor, but it was similar to human classical hemangiopericytoma (HEP) and canine HEP classified by Avallon and others.
著者
Takahisa YAMAMOTO Koshi MITACHI Takashi SUZUKI
出版者
社団法人 日本機械学会
雑誌
JSME International Journal Series B Fluids and Thermal Engineering (ISSN:13408054)
巻号頁・発行日
vol.48, no.3, pp.610-617, 2005 (Released:2006-02-15)
参考文献数
13
被引用文献数
16 24

The Molten Salt Reactor (MSR) is a thermal neutron reactor with graphite moderation and operates on the thorium-uranium fuel cycle. The feature of the MSR is that fuel salt flows inside the reactor during the nuclear fission reaction. In the previous study, the authors developed numerical model with which to simulate the effects of fuel salt flow on the reactor characteristics. In this study, we apply the model to the steady-state analysis of a small MSR system and estimate the effects of fuel flow. The model consists of two-group neutron diffusion equations for fast and thermal neutron fluxes, transport equations for six-group delayed neutron precursors and energy conservation equations for fuel salt and the graphite moderator. The following results are obtained: (1) in the rated operation condition, the peaks of the neutron fluxes slightly move toward the bottom from the center of the reactor and the delayed neutron precursors are significantly carried by the fuel salt flow, and (2) the extension of residence time in the external-loop system and the rise of the fuel inflow temperature show weak negative reactivity effects, which decrease the neutron multiplication factor of the small MSR system.