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41.
The hair length of Japanese monkeys was investigated for a period of one year and the molting phenomenon was clarified. Nine
monkeys were employed in the study. The molting of the Japanese monkey was found to be of a seasonal type and occurred once
during the year. The molting continued for one to four months in each monkey. The hair of the Japanese monkeys was wholly
replaced during the period from April to August. The hair length was thus short in summer, and long in winter. Hair replacement
in pregnant females began after parturition and was generally later than that in other individuals. During molting, both new
and old hairs could be observed simultaneously in the same region of the body. The hair replacement ended around summer when
the hair became the shortest. The new hairs continued to grow after molting and became the longest towards autumn or winter.
Thus, the summer coat and the winter coat were essentially the same in the Japanese monkey. Such annual changes in the hair
of the Japanese monkey were considered to be suitable for the climate of Japan. 相似文献
42.
The characteristics of serial cross-sections of hairs collected from an adult male Japanese monkey were investigated. Cross-sections
were made of five to eight pieces per hair. The shapes of the cross-sections were elliptical or rounded on the whole. The
fibre indices of the sections ranged from 83 to 100. In particular, those of proximal (basal) sections were close to 100.
The hair diameter was 86.4 μ at maximum and 27.2 μ at minimum. A tendency was observed for the longer hairs to have thicker
diameters. The changes in thickness along the fibre shaft were slightly different in relation to hair length. The thickest
point was at around the middle of the fibre in the intermediate hair, somewhat towards the top of the central part in the
long hair, and somewhat towards the base in the short hair. The hair of the Japanese monkey, however, was considered to be
scanty in changes along the fibre shaft in comparison with many other animals. Medullae could scarcely be seen in the short
hair and in the terminal and proximal sections of all hairs. Their shapes in cross-section were not uniform and rough at the
margins. The fibre-medulla indices were generally less than 30 and smaller than those of many other mammals. Pigmentary granules
were observed in all sections examined. The granules were black-grey in sections of the black-grey coloured part and yellow
in the yellowish sections. They were dense in distal sections and scarce in sections close to the base. The cross-sectional
appearance of the thickest part of the long hair was considered to be useful for hair identification, since it was good in
pigmentation and medullation and relatively small fibre index. 相似文献
43.
Tamami Nakano Kyoko Tanaka Yuuki Endo Yui Yamane Takahiro Yamamoto Yoshiaki Nakano Haruhisa Ohta Nobumasa Kato Shigeru Kitazawa 《Proceedings. Biological sciences / The Royal Society》2010,277(1696):2935-2943
Eye tracking has been used to investigate gaze behaviours in individuals with autism spectrum disorder (ASD). However, traditional analysis has yet to find behavioural characteristics shared by both children and adults with ASD. To distinguish core ASD gaze behaviours from those that change with development, we examined temporo-spatial gaze patterns in children and adults with and without ASD while they viewed video clips. We summarized the gaze patterns of 104 participants using multidimensional scaling so that participants with similar gaze patterns would cluster together in a two-dimensional plane. Control participants clustered in the centre, reflecting a standard gaze behaviour, whereas participants with ASD were distributed around the periphery. Moreover, children and adults were separated on the plane, thereby showing a clear effect of development on gaze behaviours. Post hoc frame-by-frame analyses revealed the following findings: (i) both ASD groups shifted their gaze away from a speaker earlier than the control groups; (ii) both ASD groups showed a particular preference for letters; and (iii) typical infants preferred to watch the mouth rather than the eyes during speech, a preference that reversed with development. These results highlight the importance of taking the effect of development into account when addressing gaze behaviours characteristic of ASD. 相似文献
44.
Haruhisa Ikumo Minoru Yoshida Akira Yoshida 《Bioscience, biotechnology, and biochemistry》2013,77(9):2089-2096
Enzymic oxidizing system of 1,3-butanediol in chicks was studied in comparison with that in rats. 1,3-Butanediol was oxidized with NAD+ as a cofactor in the cytosol fraction of chick liver, kidney, and rat liver. NADP+ was about 40% as effective as NAD+ in chick liver, kidney, whereas the former was ineffective in rat liver. Inhibitory effect of pyrazole on 1,3-butanediol dehydrogenase activity was recognized distinctly both in chicks and rats, but the effect was much higher in rat liver than that in chick liver and kidney. Both in chicks and rats, the conversion of 1,3-butanediol to β-hydroxybutyric acid was detected clearly, and the rate of β-hydroxybutyrate production increased remarkably by employing NAD+-regenerating system, i.e., lactic dehydrogenase and pyruvic acid. β-Hydroxybutyric acid was also formed from acetaldol, the most probable intermediate of 1,3-butanediol, with NAD+ both in chicks and rats. From the observations for coenzyme specificity, inhibitory effect of pyrazole, and so on, it is concluded that appreciable difference may be present in 1,3-butanediol oxidizing system between chicks and rats. 相似文献
45.
Yoshitaka Tashiro Makoto Urushitani Haruhisa Inoue Masato Koike Yasuo Uchiyama Masaaki Komatsu Keiji Tanaka Maya Yamazaki Manabu Abe Hidemi Misawa Kenji Sakimura Hidefumi Ito Ryosuke Takahashi 《The Journal of biological chemistry》2012,287(51):42984-42994
Evidence suggests that protein misfolding is crucially involved in the pathogenesis of amyotrophic lateral sclerosis (ALS). However, controversy still exists regarding the involvement of proteasomes or autophagy in ALS due to previous conflicting results. Here, we show that impairment of the ubiquitin-proteasome system, but not the autophagy-lysosome system in motor neurons replicates ALS in mice. Conditional knock-out mice of the proteasome subunit Rpt3 in a motor neuron-specific manner (Rpt3-CKO) showed locomotor dysfunction accompanied by progressive motor neuron loss and gliosis. Moreover, diverse ALS-linked proteins, including TAR DNA-binding protein 43 kDa (TDP-43), fused in sarcoma (FUS), ubiquilin 2, and optineurin were mislocalized or accumulated in motor neurons, together with other typical ALS hallmarks such as basophilic inclusion bodies. On the other hand, motor neuron-specific knock-out of Atg7, a crucial component for the induction of autophagy (Atg7-CKO), only resulted in cytosolic accumulation of ubiquitin and p62, and no TDP-43 or FUS pathologies or motor dysfunction was observed. These results strongly suggest that proteasomes, but not autophagy, fundamentally govern the development of ALS in which TDP-43 and FUS proteinopathy may play a crucial role. Enhancement of proteasome activity may be a promising strategy for the treatment of ALS. 相似文献
46.
Kosaka N Iguchi H Yoshioka Y Hagiwara K Takeshita F Ochiya T 《The Journal of biological chemistry》2012,287(2):1397-1405
Normal epithelial cells regulate the secretion of autocrine and paracrine factors that prevent aberrant growth of neighboring cells, leading to healthy development and normal metabolism. One reason for tumor initiation is considered to be a failure of this homeostatic cell competitive system. Here we identify tumor-suppressive microRNAs (miRNAs) secreted by normal cells as anti-proliferative signal entities. Culture supernatant of normal epithelial prostate PNT-2 cells attenuated proliferation of PC-3M-luc cells, prostate cancer cells. Global analysis of miRNA expression signature revealed that a variety of tumor-suppressive miRNAs are released from PNT-2 cells. Of these miRNAs, secretory miR-143 could induce growth inhibition exclusively in cancer cells in vitro and in vivo. These results suggest that secretory tumor-suppressive miRNAs can act as a death signal in a cell competitive process. This study provides a novel insight into a tumor initiation mechanism. 相似文献
47.
48.
Sadao Kuromitsu Hiroyuki Yokota Masashi Hiramoto Masatoshi Yuri Masanori Naitou Naoto Nakamura Shigeki Kawabata Masato Kobori Masao Katoh Kiyoshi Furuchi Haruhisa Mita Tetsuo Yamada 《Molecular & cellular proteomics : MCP》2009,8(6):1318-1323
Purification of biologically active proteins from complex biological sources is a difficult task, usually requiring large amounts of sample and many separation steps. We found an active substance in a serum response element-dependent luciferase reporter gene bioassay in interstitial cystitis urine that we attempted to purify with column chromatography and the bioassay. With anion-exchange Mono Q and C4 reversed-phase columns, apparently sharp active peaks were obtained. However, more than 20 kinds of proteins were identified from the active fractions with MS, indicating that the purification was not complete. As further purification was difficult, we chose a candidate molecule by means of studying the correlation between MS protein identification scores and bioassay responses of chromatographic fractions near the active peaks. As a result, epidermal growth factor (EGF) was nominated as a candidate molecule among the identified proteins because the elution profile of EGF was consistent with that of the bioassay, and the correlation coefficient of EGF between MS protein identification scores and bioassay responses was the highest among all the identified proteins. With recombinant EGF and anti-EGF and anti-EGF receptor antibodies, EGF was confirmed to be the desired substance in interstitial cystitis urine. This approach required only 20 ml of urine sample and two column chromatographic steps. The combination of MS protein identification and bioassay of chromatographic fractions may be useful for identifying biologically active substances from complex protein sources.Purification and identification of biologically active proteins existing in minute amounts from biological sources such as urine is still a difficult task (1). It requires a large volume of the sample and many separation steps for purification (2, 3). Nevertheless the recent progress of MS has dramatically changed protein analysis (4). With MS, smaller protein samples can be used than with classical protein identification methods such as N-terminal peptide sequencing.Interstitial cystitis (IC)1 is a chronic inflammatory disease characterized by frequency and urgency and/or severe pelvic pain (5). The International Continence Society also selected the term “painful bladder syndrome” for IC (6). The quality of life of IC patients is extremely low because of their severe symptoms. The pathogenesis of IC is unclear, and effective treatments have not been established. To elucidate the mechanism of IC pathogenesis, we attempted to find characteristic proteins in IC urine using proteomics techniques and have already reported active neutrophil elastase as an IC urinary marker (7). We had also performed gene expression analysis of IC bladder tissues using GeneChip technology and found that mRNA expression of GPR18, a member of the G-protein-coupled receptors, was higher in IC bladder than in the control.2 We tried to confirm whether GPR18 endogenous ligand existed in IC urine by using a bioassay with GPR18 transfectant cells.In the present study, the existence of an active substance in IC urine was suggested in the bioassay using the serum response element (SRE)-dependent luciferase reporter gene with the stable recombinant HEK293 cell line expressing GPR18. We thought that the response was derived from GPR18 and tried to purify the active substance from a small volume of IC urine using chromatographic techniques. Among the many proteins identified from partially purified samples, we clearly nominated epidermal growth factor (EGF) as a candidate molecule judging from the correlation between MS protein identification and the bioassay of chromatographic fractions. With recombinant EGF and anti-EGF antibody, EGF was confirmed to be the desired substance found in IC urine. The complete inhibition of the bioassay response by anti-EGF receptor antibody also indicated that the response was based on the EGF receptor, not GPR18, suggesting that GPR18 overexpression enhanced the EGF signal via the endogenous EGF receptor of the HEK293 cell line. 相似文献
49.
Tamami Nakano Haruhisa Ota Nobumasa Kato Shigeru Kitazawa 《Proceedings. Biological sciences / The Royal Society》2010,277(1684):1027-1030
Individuals with autism spectrum disorders (ASD) are superior in processing local features. Frith and Happe conceptualize this cognitive bias as ‘weak central coherence’, implying that a local enhancement derives from a weakness in integrating local elements into a coherent whole. The suggested deficit has been challenged, however, because individuals with ASD were not found to be inferior to normal controls in holistic perception. In these opposing studies, however, subjects were encouraged to ignore local features and attend to the whole. Therefore, no one has directly tested whether individuals with ASD are able to integrate local elements over time into a whole image. Here, we report a weakness of individuals with ASD in naming familiar objects moved behind a narrow slit, which was worsened by the absence of local salient features. The results indicate that individuals with ASD have a clear deficit in integrating local visual information over time into a global whole, providing direct evidence for the weak central coherence hypothesis. 相似文献
50.
Hippolyte K. Wabo Haruhisa Kikuchi Yasuhiro Katou Pierre Tane Yoshiteru Oshima 《Phytochemistry letters》2010,3(2):104-107
A new xanthone, 3,4-dihydro-8,10,12-trihydroxy-2,2-dimethylpyrano[2,3-b]xanthen-11(2H)-one or butyraxanthone E (1), along with the known compounds 30-epi-cambogin (2), 1,7-dihydroxyxanthone (3) and 1,5-dihydroxyxanthone (4) were isolated from the roots of Pentadesma butyracea. Their structures were elucidated by spectroscopic means and comparison with published data. Their antiproliferative activities were evaluated against Drosophila S2 cells and two human cancer cell lines, THP-1 (leukemia) and HCT116 (colon cancer). Compounds 1 and 2 showed moderate antiproliferative activity against Drosophila S2 cells and the HCT116 cell line, respectively. Compound 2 was active against Drosophila S2 cells. 相似文献