The Somatic Reproductive Tissues of <i>C. elegans</i> Promote Longevity through Steroid Hormone Signaling

Yamawaki, Tracy M.,Berman, Jennifer R.,Suchanek-Kavipurapu, Monika,McCormick, Mark,Gaglia, Marta Maria,Lee, Seung-Jae,Kenyon, Cynthia Public Library of Science 2010 PLoS biology Vol.8 No.8

<▼1><P>Removal of the germ cells of <I>C. elegans</I> extends lifespan in part because signals from the somatic reproductive tissues activate the nuclear hormone receptor DAF-12.</P></▼1><▼2><P>In <I>Caenorhabditis elegans</I> and <I>Drosophila melanogaster</I>, removing the germline precursor cells increases lifespan. In worms, and possibly also in flies, this lifespan extension requires the presence of somatic reproductive tissues. How the somatic gonad signals other tissues to increase lifespan is not known. The lifespan increase triggered by loss of the germ cells is known to require sterol hormone signaling, as reducing the activity of the nuclear hormone receptor DAF-12, or genes required for synthesis of the DAF-12 ligand dafachronic acid, prevents germline loss from extending lifespan. In addition to sterol signaling, the FOXO transcription factor DAF-16 is required to extend lifespan in animals that lack germ cells. DAF-12/NHR is known to assist with the nuclear accumulation of DAF-16/FOXO in these animals, yet we find that loss of DAF-12/NHR has little or no effect on the expression of at least some DAF-16/FOXO target genes. In this study, we show that the DAF-12-sterol signaling pathway has a second function to activate a distinct set of genes and extend lifespan in response to the somatic reproductive tissues. When germline-deficient animals lacking somatic reproductive tissues are given dafachronic acid, their expression of DAF-12/NHR-dependent target genes is restored and their lifespan is increased. Together, our findings indicate that in <I>C. elegans</I> lacking germ cells, the somatic reproductive tissues promote longevity via steroid hormone signaling to DAF-12.</P></▼2><▼3><P><B>Author Summary</B></P><P>Reproductive tissues are known to generate important intercellular signals. For example, in mammals, the reproductive tissues produce steroid hormones such as estrogen and testosterone that have profound effects on development and physiology. Studies of the nematode <I>C. elegans</I> and other organisms have shown that the reproductive system can also affect the rate at which an animal ages. Removal of <I>C. elegans</I>' germ cells extends lifespan but this effect is not simply due to sterility, as removal of both the somatic reproductive tissues and the germ cells does not extend lifespan. Instead, loss of the germ cells extends lifespan by activating a pathway that requires input from the somatic gonad. In this study, we demonstrate that the somatic reproductive tissues promote longevity by controlling the activity of a steroid signaling pathway that regulates the DAF-12 nuclear hormone receptor.</P></▼3>

Impact of Sleep Disorders, Quality of Life and Gastric Emptying in Distinct Subtypes of Functional Dyspepsia in Japan

( Hiroshi Yamawaki ),( Seiji Futagami ),( Mayumi Shimpuku ),( Hitomi Sato ),( Taiga Wakabayashi ),( Yuuta Maruki ),( Yasuhiro Kodaka ),( Hiroyuki Nagoya ),( Tomotaka Shindo ),( Tetsuro Kawagoe ),( Cho 대한소화기기능성질환·운동학회 2014 Journal of Neurogastroenterology and Motility (JNM Vol.20 No.1

Background/Aims The association between clinical symptoms, gastric emptying, quality of life and sleep disorders in distinct functional dyspepsia (FD) patients has not been studied yet in detail. Methods We enrolled 79 FD patients (postprandial distress syndrome [PDS], n = 65; epigastric pain syndrome [EPS], n = 47; EPS-PDS overlap, n = 33) and 44 healthy volunteers. Gastric motility was evaluated. We used Rome III criteria to evaluate clinical symptoms and State-Trait Anxiety Inventory (STAI) scores to determine anxiety status. Sleep disorder was evaluated using the Pittsburgh Sleep Quality Index scores. Results There were no significant differences in age, sex and Helicobacter pylori positivity between FD subtypes and healthy volunteers. The scores of Glasgow dyspepsia severity scores (GDSS), SF-8 and Pittsburgh Sleep Quality Index (PSQI) in distinct subtypes of FD patients were significantly different from those in healthy volunteers. However, there were not significant differences in these scores, Tmax and T1/2 among 3 subtypes of FD patients. PSQI score was significantly (P = 0.027, P = 0.002 and P = 0.039, respectively) associated with GDSS among EPS, PDS and EPS-PDS overlap patients. In addition, 8-item short form health survey (SF-8; Physical Component Score and Mental Component Score) was significantly associated with global PSQI score in PDS and EPS-PDS overlap patients. In contrast, SF-8 (Mental Component Score) only was significantly linked to global PSQI score in EPS patients. Conclusions Prevalences for sleep disorders, gastric motility and quality of life in 3 subtypes of FD patients were similar levels. In PDS and EPS-PDS overlap patients, SF-8 was significantly associated with global PSQI score. (J Neurogastroenterol Motil 2014;20:104-112)

A Note on Three-Dimensional Firing Squad Synchronization Algorithm

Takuya Yamawaki,Takashi Amesara,Hiroshi Umeo 대한전자공학회 2008 ITC-CSCC :International Technical Conference on Ci Vol.2008 No.7

The firing squad synchronization problem on cellular automata has been studied extensively for more than forty years, and a rich variety of synchronization algorithms have been proposed [1-10]. In the present paper, we propose an optimumtime firing squad synchronization algorithm for three-dimensional cellular automata. The algorithm can synchronize any threedimensional array of size mㆍnㆍℓ with a general at an arbitrary corner cell at exactly mㆍnㆍℓ+ max(m, n, ℓ)ㆍ4 steps. A lower bound in time complexity is also given.

Leu72Met408 Polymorphism of the Ghrelin Gene Is Associated With Early Phase of Gastric Emptying in the Patients With Functional Dyspepsia in Japan

( Hiroshi Yamawaki ),( Seiji Futagami ),( Mayumi Shimpuku ),( Tomotaka Shindo ),( Yuuta Maruki ),( Hiroyuki Nagoya ),( Yasuhiro Kodaka ),( Hitomi Sato ),( Katya Gudis ),( Tetsuro Kawagoe ),( Choitsu S 대한소화기기능성질환·운동학회 2015 Journal of Neurogastroenterology and Motility (JNM Vol.21 No.1

Background/Aims There are no available data about the relationship between ghrelin gene genotypes and early phase of gastric emptying in functional dyspepsia (FD) as defined by Rome III classification. Methods We enrolled 74 patients presenting with typical symptoms of FD and 64 healthy volunteers. Gastric motility was evaluated using the 13C-acetate breath test. We used Rome III criteria to evaluate upper abdominal symptoms and self-rating questionnaires for depression (SRQ-D) scores to determine status of depression. The Arg51Gln (346G>A), preproghrelin (3056T>C), Leu72Met (408C>A), Gln90Leu (3412T>A) and G-protein 3 (825C>T) polymorphisms were analyzed in the DNA from blood samples of enrolled subjects. Genotyping was performed by polymerase chain reaction. Results There was a significant relationship between the Gln90Leu3412 genotype and SRQ-D score in FD patients (P = 0.009). Area under the curve at 15 minutes (AUC15) value was significantly associated with the Leu72Met408 genotype (P = 0.015) but not with entire gastric emptying. Conclusions The Leu72Met (408C>A) single nucleotide polymorphism was significantly associated with early phase of gastric emptying in FD patients. Further studies will be necessary to clarify the association between ghrelin gene single nucleotide polymorphisms and early phase of gastric emptying in FD patients.

MIPEX and Japan : Findings and Reflections

Kondo Atsushi and Yamawaki Keizo Sookmyung institute for Multicultural Studies 2013 The Journal of Migration & Society Vol.4 No.2

마이켈슨 간섭계를 이용한 레이저 여기 초음파의 검출

김경조,山脇 壽,장경영 한국비파괴검사학회 2000 한국비파괴검사학회지 Vol.20 No.1

본 논문에서는 고출력 펄스 Nd:YAG 레이저를 이용해서 원반형 시편의 한쪽 면에서 초음파를 발생시키고 반대면에서 피드백 제어에 의해서 안정화된 마이켈슨 간섭계를 이용하여 열탄성 영역에서의 초음파를 검출하였다. 이론식에 의해서 계산된 열탄성 영역에서의 초음파 변위 파형이 실험에서 얻어진 파형과 유사한 것을 확인하였고, 특히 종파와 횡파의 음속이 접촉식 트랜스듀서를 이용하여 펄스-에코법으로 측정한 음속과 거의 일치하는 것을 확인하였다. 레이저 초음파를 이용한 응용에의 하나로 원반형 시편을 노 안에 넣고 음속을 계측한 결과 온도의 증가에 따라 음속이 감소하는 것을 확인하였다. In this paper, ultrasonic wave in the thermoelastic regime was generated in a steel disk by illuminating a pulse laser (Q-switched Nd:YAG) on the surface of the sample and was detected on the other side by Michelson interferometer which was stabilized by feed back control. The experimentally detected displacement waveform of the ultrasonic wave showed good agreement with the theoretically expected one. Also it was shown that sound speeds of longitudinal and shear wave were similar to ones measured by pulse-echo method using a contact transducer. As an application of the noncontact ultrasonic measurement by using laser based ultrasonics, the sound speed in the sample was monitored while the sample was heated in a furnace, and the result showed that it decreased according to the increase of sample temperature.

MIPEX and Japan: Findings and Reflections

Kondo Atsushi,Yamawaki Keizo 숙명여자대학교 아시아여성연구원 2014 OMNES: The Journal of Multicultural Society Vol.4 No.2

This paper discusses major findings of MIPEX for Japan. The authors were two of the three reviewers when MIPEX was applied to Japanese migrant integration policy in 2010. In terms of the overall scores, Japan ranks as one of the lowest, that is, the 32th out of 37 countries. Among the seven policy areas, particularly low were anti-discrimination and education, followed by political participation and citizenship. The major weakness in anti-discrimination policy lies in the lack of an anti-discrimination law while that of education policy originates in several factors, including insufficient consideration of special needs of foreign children and the lack of intercultural education for all children. In the concluding section, this paper summarizes the major findings and policy implications for Japan as well as raising some issues concerning limitations of MIPEX.

Curvelet Approach for Deep-sea Sonar Image Denoising, Contrast Enhancement and Fusion

Lu, Huimin,Yamawaki, Akira,Serikawa, Seiichi The Korean Institute of Electrical Engineers 2013 The Journal of International Council on Electrical Vol.3 No.3

Side-scan sonar acquires high quality imagery of the seafloor with very high spatial resolution but poor locational accuracy. However, multi-beam sonar obtains high precision position and underwater depth in seafloor points. In order to fully utilize all information of these two types of sonars, it is necessary to fuse the two kinds of sonar data. This paper gives curvelet transform for enhancing the signals or details in different scales separately. It also proposes a new intensity sonar image fusion method, which is based on curvelet transform. Considering the sonar image forming principle, for the low frequency curvelet coefficients, we use the maximum local energy method to calculate the energy of two sonar images. For the high frequency curvelet coefficients, we take absolute maximum method as a measurement. The main attribute of this paper is: Firstly, the multi-resolution analysis method is well adapted the cured-singularities and point-singularities. It is useful for sonar intensity image enhancement. Secondly, maximum local energy is well performing the intensity sonar images, which can achieve perfect fusion result. The experimental results show that the method can be used in the flat seafloor or the isotropic seabed. Compared with wavelet transform method, this method can get better performance.

Description Method for High-level Synthesis of Histogram Generation and Their Evaluation

Moena Yamasaki,Akira Yamawaki 대한전자공학회 2019 IEIE Transactions on Smart Processing & Computing Vol.8 No.3

To achieve high performance and low power simultaneously in an embedded image–processing product, hardware implementation of high computational–software processing is needed. Hardware development, however, is a large burden on the developer. High-level synthesis (HLS) for automatically converting software into hardware can significantly reduce the design burden. To use HLS technology efficiently, a software program must be described considering the hardware organization that the HLS tool will generate. Histogram generation is one of the important basic functions in image processing. In histogram generation, data dependency on reading and writing to the same address in the histogram hinders ideal pipelining by an HLS tool.

An Evaluation of Burst Transfer Inferred by a High-level Synthesis Tool

Yuki Yamagata,Akira Yamawaki 대한전자공학회 2019 IEIE Transactions on Smart Processing & Computing Vol.8 No.2

High-level synthesis (HLS) is technology that automatically converts software to digital hardware. HLS has gained attention as a promising technology that can reduce the burden of hardware development. However, if a software program converted by HLS does not consider organization of the hardware, the current HLS technology cannot convert software to proper digital hardware. One of the characteristics of the hardware to be considered is burst transfer to memory access. Burst transfer attempts to speed up memory access by packing continuous data into a single address. This paper discusses a rectangle-drawing case study that demonstrates how to describe a C program so an HLS tool can infer burst transfer with an arbitrary burst length. Moreover, we consider the necessity to suppress optimization performed by the HLS tool to prevent increasing the amount of digital hardware when we implement the arbitrary burst length. Experiments clarify how performance and the hardware scale change based on the difference in the burst length and suppression of optimization.