著者

Yukuo Abe Masahiko Taniguchi Hideki Suganuma Masahiro Saito Toshinori Kojima Yasuyuki Egashira Yukiyo Yamamoto Koichi Yamada

出版者

公益社団法人 化学工学会

雑誌

JOURNAL OF CHEMICAL ENGINEERING OF JAPAN (ISSN:00219592)

巻号頁・発行日

vol.36, no.4, pp.376-382, 2003 (Released:2004-02-21)

参考文献数

13

被引用文献数

2 2 2

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Global warming is a serious problem requiring immediate countermeasures. Large-scale afforestation in arid areas for the aim of absorbing CO2 is considered to be one of these measures and the research activities for it have been carried out in Leonora, Western Australia. In this study, the relationship between the biomass distribution and topographic features was examined in order to collect basic information for the selection of suitable afforestation regions in the research area using a biomass distribution map and some topographic elements. The results were as follows.(1) Plant growth is related to the movement of and the volume of runoff water derived from inequality of the ground, which leads to a biased distribution of nutrient accumulation and of surface soil thickness.(2) The total potential biomass estimated from the present topography is greater than the present biomass in the 30 km × 50 km research area. A mass of 319 kt-C could be absorbed in the research area without any improvements in the landform.(3) A substantial improvement on the environment utilizing vast arid areas by afforestation is necessary to fix enough carbon deterring global warming.

著者

Takamichi Yamamoto Seung Bong Hong Masahiro Shimizu Katsuaki Sato Yotaro Numachi

出版者

日本てんかん学会

雑誌

Epilepsy & Seizure (ISSN:18825567)

巻号頁・発行日

vol.7, no.1, pp.55-65, 2014-08-15 (Released:2014-08-15)

参考文献数

12

被引用文献数

5

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Purpose: To evaluate the efficacy and safety of lamotrigine monotherapy in patients with newly diagnosed partial seizures including secondarily generalized seizures or generalized tonic-clonic seizures, and those with recurrent seizures in Japan and South Korea.Methods: The study was a multi-center, open-label, evaluation of lamotrigine monotherapy in patients with newly diagnosed epilepsy or epilepsy with recurrent seizures. The primary endpoint was the seizure-free rate in the maintenance phase.Results: A total of 67 patients were enrolled; 52 patients completed 6 weeks of treatment (the escalation phase) and 42 patients completed 30 weeks of treatment (the escalation phase and the maintenance phase). The seizure-free rate in the maintenance phase for all seizure types was 43.1%. Adverse events (AEs) were reported in 82% (53/65) of patients. The most common AEs were headache (14/65, 22%), nasopharyngitis (12/65, 18%) and rash (7/65, 11%).Conclusion: The seizure-free rate with lamotrigine monotherapy in the maintenance phase was 43.1% for all seizure types. Lamotrigine monotherapy appears to be effective in patients with newly diagnosed epilepsy and those with recurrent seizures in Japan and South Korea. The safety profile of lamotrigine in this monotherapy study was similar to that observed in patients with adult bipolar disorder treated with lamotrigine monotherapy.

著者

Ninagawa Satoshi Okada Tetsuya Sumitomo Yoshiki Kamiya Yukiko Kato Koichi Horimoto Satoshi Ishikawa Tokiro Takeda Shunichi Sakuma Tetsushi Yamamoto Takashi Mori Kazutoshi

出版者

Rockefeller University Press

雑誌

The Journal of cell biology (ISSN:15408140)

巻号頁・発行日

vol.206, no.3, pp.347-356, 2014-08-04

被引用文献数

126

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構造異常糖タンパク質の分解に必須な糖鎖刈り込み機構を解明 -最新ゲノム編集解析により醜いアヒルの子が美しい白鳥に変身-. 京都大学プレスリリース. 2014-09-02.

著者

Tomonori ANDO Yoshiyuki KABASHIMA Hisanao TAKAHASHI Osamu WATANABE Masaki YAMAMOTO

出版者

The Institute of Electronics, Information and Communication Engineers

雑誌

IEICE TRANSACTIONS on Fundamentals of Electronics, Communications and Computer Sciences (ISSN:09168508)

巻号頁・発行日

vol.E94-A, no.6, pp.1247-1256, 2011-06-01

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We study nn random symmetric matrices whose entries above the diagonal are iid random variables each of which takes 1 with probability p and 0 with probability 1-p, for a given density parameter p=α/n for sufficiently large α. For a given such matrix A, we consider a matrix A ' that is obtained by removing some rows and corresponding columns with too many value 1 entries. Then for this A', we show that the largest eigenvalue is asymptotically close to α+1 and its eigenvector is almost parallel to all one vector (1,...,1).

著者

山本 正信 Yamamoto Masanobu

出版者

電子情報通信学会

雑誌

電子通信学会論文誌 D (ISSN:0374468X)

巻号頁・発行日

vol.69, no.11, pp.p1631-1638, 1986-11

被引用文献数

42

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両眼ステレオ視は,3次元情報の手軽な獲得法ではあるが,左右画像間の対応付けの際に,(1)多重対応,(2)隠れ,(3)順序の逆転,(4)水平エッジ,などがある場合に於て,対応点探索が困難になる.本論文では,視点を移動させつつ得られた連続ステレオ画像から,シーンの3次元情報を推定する手法を提案する.まず,連続ステレオ画像から,見かけの運動軌跡が線分として画像化されるような2次元画像を合成する.その時,対応付け問題は,合成画像上の線分検出問題として簡略化される.検出された線分の相互関係を調べることにより,隠れの検出や,見かけの逆転が起きた場合の対応付けも容易になる.更に,視点を一方向だけではなく,それと直交する方向にも移動させることにより,エッジの向きに依存しない一意な対応付けが可能となる.大量の連続ステレオ画像が高速に入力可能な装置を構成し,実際に,複雑なシーンの3次元構造を復元する.

著者

Ryoko Yamagishi Tomohiko Wakayama Hiroki Nakata Kannika Adthapanyawanich Tewarat Kumchantuek Miyuki Yamamoto Shoichi Iseki

出版者

日本組織細胞化学会

雑誌

ACTA HISTOCHEMICA ET CYTOCHEMICA (ISSN:00445991)

巻号頁・発行日

vol.47, no.3, pp.95-102, 2014-06-30 (Released:2014-06-28)

参考文献数

28

被引用文献数

2 10

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In the major salivary glands of mice, acinar cells in the parotid gland (PG) are known to be the main site for the production of the digestive enzyme α-amylase, whereas α-amylase production in the submandibular gland (SMG) and sublingual gland (SLG), as well as the cell types responsible for α-amylase production, has been less firmly established. To clarify this issue, we examined the expression and localization of both the mRNA and protein of α-amylase in the major salivary glands of male and female mice by quantitative and histochemical methods. α-amylase mRNA levels were higher in the order of PG, SMG, and SLG. No sexual difference was observed in α-amylase mRNA levels in the PG and SLG, whereas α-amylase mRNA levels in the female SMG were approximately 30% those in the male SMG. Using in situ hybridization and immunohistochemistry, signals for α-amylase mRNA and protein were found to be strongly positive in acinar cells of the PG, serous demilune cells of the SLG, and granular convoluted tubule (GCT) cells of the male SMG, weakly positive in seromucous acinar cells of the male and female SMG, and negative in mucous acinar cells of the SLG. These results clarified that α-amylase is produced mainly by GCT cells and partly by acinar cells in the SMG, whereas it is produced exclusively by serous demilune cells in the SLG of mice.

著者

Shinya Furukawa Shin Yamamoto Yasuhiko Todo Kotatsu Maruyama Teruki Miyake Teruhisa Ueda Tetsuji Niiya Takatoshi Senba Masamoto Torisu Teru Kumagi Syozo Miyauchi Takenori Sakai Hisaka Minami Hiroaki Miyaoka Bunzo Matsuura Yoichi Hiasa Morikazu Onji Takeshi Tanigawa

出版者

(社)日本内分泌学会

雑誌

Endocrine Journal (ISSN:09188959)

巻号頁・発行日

pp.EJ14-0206, (Released:2014-08-07)

被引用文献数

10 44

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Subclinical hypothyroidism (SCH) has been associated with type 2 diabetes mellitus. However, it is unknown whether common complications of type 2 diabetes, such as diabetic nephropathy, are also present with SCH. Here, we investigated the association between SCH and diabetic nephropathy among Japanese patients with type 2 diabetes mellitus. In this multicenter cross-sectional study, we recruited 414 such patients who had no previous history of thyroid disease. Serum thyroid hormone levels and the urinary albumin:creatinine ratio were measured. SCH was defined as an elevated thyroid-stimulating hormone (TSH) level (>4.0 mIU/L), and diabetic nephropathy was defined as creatinine levels ≥300 mg/g. The prevalence of SCH was 8.7% (n = 36) among patients with type 2 diabetes mellitus. The SCH group had a higher prevalence of dyslipidemia (p = 0.008) and diabetic nephropathy (p = 0.014) than the euthyroid group. Multivariate analysis identified significant positive associations between diabetic nephropathy and SCH (odds ratio [OR], 3.51; 95% confidence interval [CI], 1.10-10.0; p = 0.034), hypertension (OR, 4.56; 95% CI, 1.69-14.7; p = 0.001), and smoking (OR, 3.02; 95% CI, 1.14-7.91; p = 0.026). SCH may be independently associated with diabetic nephropathy in Japanese patients with type 2 diabetes mellitus.

著者

Shuhei Yamamoto Atsuhiko Matsunaga Guoqin Wang Keika Hoshi Kentaro Kamiya Chiharu Noda Masahiko Kimura Minako Yamaoka-Tojo Takashi Masuda

出版者

一般社団法人 インターナショナル・ハート・ジャーナル刊行会

雑誌

International Heart Journal (ISSN:13492365)

巻号頁・発行日

pp.14-017, (Released:2014-08-04)

被引用文献数

3 14

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The purpose of this study was to clarify the effect of standing balance training on walking speed (short-term outcome) and cardiac events (long-term outcome) in elderly ischemic heart disease (IHD) patients. This was a retrospective cohort study. Ninety-two elderly (≥ 65 years) IHD patients who underwent an inpatient cardiac rehabilitation program were assigned to two groups: a balance group that received standing balance training in addition to conventional (aerobic and resistance) training and a conventional group. Standing balance was assessed by one-leg standing time and a postural stability index reflecting dynamic balance, and normal walking speed was measured at baseline and hospital discharge. Patients were followed for up to 3 years or until a cardiac event occurred. There were no significant differences in clinical characteristics between the groups. Both groups showed a significant change in normal walking speed from baseline to hospital discharge (P < 0.001, respectively), and normal walking speed was significantly higher in the balance group compared to the conventional group (P = 0.001). The postural stability index improved significantly only in the balance group (P = 0.005). Multivariable analyses using Cox proportional hazards model confirmed that standing balance training (hazard ratio [HR]: 0.408; 95% confidence interval [CI]: 0.162-1.029; P = 0.058) and fast walking speed (HR: 0.362; 95% CI: 0.137-0.957; P = 0.041) were associated with cardiac events. These findings show that standing balance training improves walking speed and reduces cardiac events, and suggests that such training can be an effective intervention for elderly IHD patients.

著者

Maiko KAWAKUBO Masaki MATSUI Sumihisa ISHIKAWA Atsushi HIRANO Osamu YAMAMOTO Yasuo TAKEDA Nobuyuki IMANISHI

出版者

公益社団法人 電気化学会

雑誌

Electrochemistry (ISSN:13443542)

巻号頁・発行日

vol.82, no.8, pp.642-646, 2014-08-05 (Released:2014-08-05)

参考文献数

14

被引用文献数

2

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Degradation processes of carbon negative electrodes for all-solid lithium polymer batteries were investigated using X-ray diffraction (XRD), electrochemical impedance spectroscopy (EIS) and Scanning Electron Microscope (SEM). The cycling performances of the electrodes are significantly affected by the mixing speed of the electrode slurry. The cross-sectional SEM images of the electrodes containing vapor-grown carbon fiber (VGCF) show that more voids remained in the electrodes, if the slurry was mixed at high speed. The voids in the composite electrode expand and increase during the cycling test of the cell resulting in the capacity fading. On the other hand, the electrodes containing carbon nanotubes (CNT) show an opposite trend, because the high mixing speed improves the dispersibility of the CNT resulting in the formation of the less voids in the electrode. The electrode containing both VGCF and CNT prepared at high mixing speed shows the best cycleability among all the electrodes. In spite of some voids initially form in the electrode, the CNT seems to have prevented further increase and expansion of the voids.

著者

Thi Nhung BUI Thi Hop LE Do Huy NGUYEN Quang Binh TRAN Thi Lam NGUYEN Danh Tuyen LE Do Van Anh NGUYEN Anh Linh VU Hiromichi AOTO Yasuhide OKUHARA Yukihiko ITO Shigeru YAMAMOTO Mitsuo KISE

出版者

Center for Academic Publications Japan

雑誌

Journal of Nutritional Science and Vitaminology (ISSN:03014800)

巻号頁・発行日

vol.60, no.3, pp.183-187, 2014 (Released:2014-07-30)

参考文献数

35

被引用文献数

3 36 7

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We have reported that newly diagnosed type 2 diabetes mellitus (DM) patients in Vietnam have a low body mass index (BMI) of around 23 and that the major factor for this is high white rice (WR) intake. Brown rice (BR) is known to be beneficial in the control of blood glucose levels; however, it has the property of unpleasant palatability. Pre-germinated brown rice (PGBR) is slightly germinated by soaking BR in water as this reduces the hardness of BR and makes it easier to eat. This study was designed to evaluate the effect of a 4-mo PGBR administration on various parameters in Vietnamese women aged 45-65 y with impaired glucose tolerance (IGT). Sixty subjects were divided into a WR or PGBR group. For the first 2 wk, WR was replaced by 50% PGBR, then for 2 wk by 75% PGBR and from the second month 100%. Before the beginning of the study and at the end of the study, 1) anthropometric measurements, 2) a nutrition survey for 3 nonconsecutive days by the 24 h recall method and 3) blood biochemical examinations were conducted. Fasting plasma concentrations of glucose and lipids and the obesity-related measurements and blood pressure were favorably improved only in the PGBR diet group. The present results suggest that replacing WR with PGBR for 4 mo may be useful in controlling body weight as well as blood glucose and lipid levels in Vietnamese women with IGT.

著者

Katsuhiko Yamamoto Zhi Zhu Masashi Unoki Naofumi Aoki

出版者

信号処理学会

雑誌

Journal of Signal Processing (ISSN:13426230)

巻号頁・発行日

vol.18, no.4, pp.205-208, 2014-07-30 (Released:2014-07-30)

参考文献数

10

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Speech scrambling methods are widely used for copyright protection and encrypting digital speech signals in order to guarantee the confidentiality of the original signals. They are very important methods for preventing eavesdropping and unauthorized copying. However, it seems to be impossible to completely recover a scrambled speech signal into the original signal. Moreover, nobody can comprehend the partial speech content from speech signals scrambled with these methods. In this paper, we propose a semi-scramble method for speech signals based on phonemic restoration. By using a speech scrambling method based on the random-bit shift of quantization bits, speech signals are converted to scrambled signals in partial intervals. We evaluated the confidentiality and efficiency of the proposed method by using two objective measures, signal-to-error ratio (SER) and perceptual evaluation of speech quality (PESQ). As a result, we confirmed that the proposed method can play a role in copyright protection for an original signal and recover a semi-scrambled speech signal into the original one. Finally, we indicated that the acoustic characteristics of signal semi-scrambled with the proposed method enable the listener to understand the speech information.

著者

Jun NISHIKAWA Richard FITZPATRICK James D. REIMER Robin J. BEAMAN Hiroyuki YAMAMOTO Dhugal J. LINDSAY

出版者

日本サンゴ礁学会

雑誌

Galaxea, Journal of Coral Reef Studies (ISSN:18830838)

巻号頁・発行日

vol.13, no.1, pp.25-26, 2011 (Released:2012-03-24)

参考文献数

3

被引用文献数

1 6 1

著者

Takuya Okamoto Takeshi Ishikawa Yoshiyuki Koyano Norifumi Yamamoto Kazuo Kuwata Masataka Nagaoka

出版者

(社)日本化学会

雑誌

Bulletin of the Chemical Society of Japan (ISSN:00092673)

巻号頁・発行日

vol.86, no.2, pp.210-222, 2013-02-15 (Released:2013-02-15)

参考文献数

95

被引用文献数

20 4

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For the purpose of providing a realistic description of the reaction mechanisms in large molecular systems, we propose a quantum mechanical/molecular mechanical (QM/MM) method combined with the ab initio fragment molecular orbital (FMO) method, i.e., the ab initio FMO-QM/MM method. By connecting a molecular dynamics (MD) program AMBER with an FMO program PAICS, we have implemented an AMBER-PAICS interface (AP-IF). Using the AP-IF, we demonstrate three example applications: (a) a hydrogen fluoride and water molecular clusters, (b) an alanine dipeptide in aqueous solution, and (c) a prion protein–GN8 complex. From these results, it is confirmed that the FMO-QM/MM method offers a good compromise between chemical accuracy and computational cost and enables us to obtain in ab initio quality the inter- and intramolecular interaction energies between molecules or residues in large molecular systems such as solution and biomolecule, by using the dynamics-based interfragment interaction energy (IFIE) analysis.

著者

Hirokazu Ohminami Kikuko Amo Yutaka Taketani Kazusa Sato Makiko Fukaya Takashi Uebanso Hidekazu Arai Megumi Koganei Hajime Sasaki Hisami Yamanaka-Okumura Hironori Yamamoto Eiji Takeda

出版者

日本酸化ストレス学会

雑誌

Journal of Clinical Biochemistry and Nutrition (ISSN:09120009)

巻号頁・発行日

vol.55, no.1, pp.15-25, 2014 (Released:2014-07-01)

参考文献数

41

被引用文献数

1 5

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A dietary combination of sucrose and linoleic acid strongly contributes to the development of metabolic disorders in Zucker fatty rats. However, the underlying mechanisms of the metabolic disorders are poorly understood. We hypothesized that the metabolic disorders were triggered at a stage earlier than the 8 weeks we had previously reported. In this study, we investigated early molecular events induced by the sucrose and linoleic acid diet in Zucker fatty rats by comparison with other combinations of carbohydrate (sucrose or palatinose) and fat (linoleic acid or oleic acid). Skeletal muscle arachidonic acid levels were significantly increased in the sucrose and linoleic acid group compared to the other dietary groups at 4 weeks, while there were no obvious differences in the metabolic phenotype between the groups. Expression of genes related to arachidonic acid synthesis was induced in skeletal muscle but not in liver and adipose tissue in sucrose and linoleic acid group rats. In addition, the sucrose and linoleic acid group exhibited a rapid induction in endoplasmic reticulum stress and abnormal lipid metabolism in skeletal muscle. We concluded that the dietary combination of sucrose and linoleic acid primarily induces metabolic disorders in skeletal muscle through increases in arachidonic acid and endoplasmic reticulum stress, in advance of systemic metabolic disorders.

著者

Tomoaki ONODA Ryuta YAMAMOTO Kyohei SAWAMURA Harutaka MURASE Yasuo NAMBO Yoshinobu INOUE Akira MATSUI Takeshi MIYAKE Nobuhiro HIRAI

出版者

日本ウマ科学会

雑誌

Journal of Equine Science (ISSN:13403516)

巻号頁・発行日

vol.25, no.2, pp.29-35, 2014 (Released:2014-06-25)

参考文献数

17

被引用文献数

4

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We propose an approach of estimating individual growth curves based on the birthday information of Japanese Thoroughbred horses, with considerations of the seasonal compensatory growth that is a typical characteristic of seasonal breeding animals. The compensatory growth patterns appear during only the winter and spring seasons in the life of growing horses, and the meeting point between winter and spring depends on the birthday of each horse. We previously developed new growth curve equations for Japanese Thoroughbreds adjusting for compensatory growth. Based on the equations, a parameter denoting the birthday information was added for the modeling of the individual growth curves for each horse by shifting the meeting points in the compensatory growth periods. A total of 5,594 and 5,680 body weight and age measurements of Thoroughbred colts and fillies, respectively, and 3,770 withers height and age measurements of both sexes were used in the analyses. The results of predicted error difference and Akaike Information Criterion showed that the individual growth curves using birthday information better fit to the body weight and withers height data than not using them. The individual growth curve for each horse would be a useful tool for the feeding managements of young Japanese Thoroughbreds in compensatory growth periods.

著者

Yamamoto Hideaki

巻号頁・発行日

2009

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制度:新 ; 報告番号:甲2813号 ; 学位の種類:博士(工学) ; 授与年月日:2009/3/15 ; 早大学位記番号:新5033

著者

Tohru Obata Yuka Suzuki Noriko Ogawa Ippei Kurimoto Hiromitsu Yamamoto Tadahide Furuno Takuma Sasaki Motohiro Tanaka

出版者

公益社団法人日本薬学会

雑誌

Biological and Pharmaceutical Bulletin (ISSN:09186158)

巻号頁・発行日

vol.37, no.5, pp.802-807, 2014-05-01 (Released:2014-05-01)

参考文献数

25

被引用文献数

3 11

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Sapacitabine (CS-682 or CYC682; 1-[2-C-cyano-2-deoxy-β-D-arabino-pentfuranosyl]N4-palmitoyl cytosine), a novel antitumor 2′-deoxycytidine analogue, shows a marked reduction in the water solubility because of the fatty acid side chain on the N4 group of the cytosine moiety. Poor water solubility is one of the important reasons why sapacitabine does not exert maximum antitumor activity. Therefore, we attempted to improve the water solubility of sapacitabine using a novel surfactant, Soluplus®, which consisted of a polyvinyl caprolactam–polyvinyl acetate–polyethylene glycol graft copolymer. In this study, we examined whether Soluplus® increased the water solubility and an antitumor activity of sapacitabine. The cytotoxicity of Soluplus® alone was lower than that of Tween 80 and Kolliphor® D-α-tocopherylpolyethylene glycol 1000 succinate (TPGS). The water solubility and the chemosensitivity of sapacitabine against several tumor cell lines to sapacitabine markedly increased upon using Soluplus®. In addition, the potential of Soluplus® including sapacitabine in increasing the antitumor activity was compared with sapacitabine alone in vivo. Although the total dose in the experimental period was considerably lower than the effective dose of sapacitabine alone, the life span of mice treated with sapacitabine containing 40 mg/mL Soluplus® increased by 150%. If Soluplus® was used as the solubilizing agent in clinical trials of sapacitabine, a low administration dose was appeared to require, and thus side effects might be prevented.

著者

Yusaku Yasuno Yoshihiro H. Inoue Masa-Toshi Yamamoto

出版者

日本遺伝学会

雑誌

Genes & Genetic Systems (ISSN:13417568)

巻号頁・発行日

vol.88, no.2, pp.113-126, 2013 (Released:2013-07-06)

参考文献数

40

被引用文献数

3

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Sex ratio distortion, which is commonly abbreviated as sex-ratio, has been studied in many Drosophila species, but the mechanism remains largely unknown. Here, we report on the sex-ratio mutant of D. simulans named excess of females (exf). The third chromosomal recessive mutation results in a sex ratio of approximately 0.2 or less (males/total). Cytological observation demonstrated that meiosis appeared to be completed normally, but that most Y chromosome-bearing nuclei failed to elongate during spermiogenesis, as revealed by fluorescence in situ hybridization using sex chromosome-specific probes. These aberrant nuclei contained membranous inclusions as revealed by electron microscopic analysis. Most of the aberrant exf spermatids failed to individualize and mature, suggesting that a later stage of spermiogenesis is involved in prevention of production of sperm with abnormal morphology. On the one hand, in exf seminal vesicles, sperm nuclei with a length of 5–8.5 μm were occasionally observed, in addition to those with wild-type sperm dimensions, that is, a length of approximately 10 μm. Thus, spermatids with less severe nuclear defects can escape elimination and be released into the seminal vesicles as mature sperm. Furthermore, we constructed His2AvD-GFP and ProtamineB-eGFP transgenic lines in D. simulans, and examined the processes involved in replacement of chromatin proteins over a time course, according to nuclear morphology. We found that both normal and abnormal sperm heads demonstrated equal chromatin replacement during late spermiogenesis. Our results suggest that exf belongs to a unique class of meiotic drive systems in that (1) intranuclear membranous inclusions cause failure of nuclear shaping of Y-bearing spermatids without affecting the histone-protamine transition, and (2) a portion of the aberrant spermatids differentiate into mature sperm; these are transferred to and stored by females.

著者

Tatsuya Yamamoto Shoji Shinamura Eigo Miyazaki Kazuo Takimiya

出版者

(社)日本化学会

雑誌

Bulletin of the Chemical Society of Japan (ISSN:00092673)

巻号頁・発行日

vol.83, no.2, pp.120-130, 2010-02-15 (Released:2010-02-15)

参考文献数

40

被引用文献数

59

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In order to gain an insight into the relationship between the molecular structure and the semiconductor characteristics of highly π-extended heteroarene-based organic semiconductors, three structural isomers of dinaphthothieno[3,2-b]thiophenes with C2h symmetry were investigated. Of these, two isomers, dinaphtho[2,1-b:2′,1′-f ]thieno[3,2-b]thiophene (2) and dinaphtho[1,2-b:1′,2′-f ]thieno[3,2-b]thiophene (3), were newly synthesized, characterized, and utilized as active semiconducting layers in organic field-effect transistors (FETs). Detailed investigation of the physicochemical properties of 2 and 3, together with another isomer, dinaphtho[2,3-b:2′,3′-f ]thieno[3,2-b]thiophene (1), indicated that the electronic structures of the three isomers are fairly different from each other despite having the same molecular formula and the same aromatic constituents. Comparison of the molecular arrangements in the crystals elucidated by X-ray structural analysis implied that the molecular shape and the thus-induced favorable intermolecular interactions play important roles in determining the entire molecular arrangement. The characteristics of 2- and 3-based FETs with maximum field-effect mobilities (μFET s) of 10−3–10−2 cm2 V−1 s−1 were inferior to those of 1-based FETs with μFET s up to 3.0 cm2 V−1 s−1. The inferior characteristics of 2- and 3-based devices were due to film morphology as elucidated by atomic force microscopy (AFM) and supported by theoretical calculations of electronic structure in the solid state. Together, the results indicate that the molecular structure and shape, even for similar heteroarenes with the same molecular formula and symmetry, are important parameters to determine the solid-state properties of organic semiconductors.

著者

Amo Kikuko Hidekazu Arai Uebanso Takashi Makiko Fukaya Megumi Koganei Hajime Sasaki Hironori Yamamoto Yutaka Taketani Eiji Takeda

出版者

日本酸化ストレス学会

雑誌

Journal of Clinical Biochemistry and Nutrition (ISSN:09120009)

巻号頁・発行日

vol.49, no.1, pp.1-7, 2011 (Released:2011-06-30)

参考文献数

52

被引用文献数

12 53

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Xylitol is widely used as a sweetener in foods and medications. Xylitol ingestion causes a small blood glucose rise, and it is commonly used as an alternative to high-energy supplements in diabetics. In previous studies, a xylitol metabolite, xylulose-5-phosphate, was shown to activate carbohydrate response element binding protein, and to promote lipogenic enzyme gene transcription in vitro; however, the effects of xylitol in vivo are not understood. Here we investigated the effects of dietary xylitol on lipid metabolism and visceral fat accumulation in rats fed a high-fat diet. Sprague-Dawley rats were fed a high-fat diet containing 0 g (control), 1.0 g/100 kcal (X1) or 2.0 g/100 kcal (X2) of xylitol. After the 8-week feeding period, visceral fat mass and plasma insulin and lipid concentrations were significantly lower in xylitol-fed rats than those in high-fat diet rats. Gene expression levels of ChREBP and lipogenic enzymes were higher, whereas the expression of sterol regulatory-element binding protein 1c was lower and fatty acid oxidation-related genes were significantly higher in the liver of xylitol-fed rats as compared with high-fat diet rats. In conclusion, intake of xylitol may be beneficial in preventing the development of obesity and metabolic abnormalities in rats with diet-induced obesity.