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991.
Murai H Takata S Maruyama M Nakano M Kobayashi D Otowa K Takamura M Yuasa T Sakagami S Kaneko S 《American journal of physiology. Heart and circulatory physiology》2006,290(2):H853-H860
Recording of neural firing from single-unit muscle sympathetic nerve activity (MSNA) is a new strategy offering information about the frequency of pure sympathetic firing. However, it is uncertain whether and when single-unit MSNA would be more useful than multiunit MSNA for analysis of various physiological stresses in humans. In 15 healthy subjects, we measured single-unit and multiunit MSNA before and during handgrip exercise at 30% of maximum voluntary contraction for 3 min and during the Valsalva maneuver at 40 mmHg expiratory pressure for 15 s. Shapes of individual single-unit MSNA were proved to be consistent and suitable for further evaluation. Single-unit and multiunit MSNA exhibited similar responses during handgrip exercise. However, acceleration of neural firing determined from single-unit MSNA became steeper than multiunit MSNA during the Valsalva maneuver. During the Valsalva maneuver, unlike handgrip exercise, the distribution of multiunit burst between 0, 1, 2, 3, and 4 spikes was significantly shifted toward multiple spikes within a given burst (P < 0.05). These results indicated that evaluation of single-unit MSNA could provide more detailed and accurate information concerning the role and responses of neuronal discharges induced by various physiological stresses in humans, especially amid intense sympathetic activity. 相似文献
992.
Matsuhashi M Endoh K Pankrushina AN Watanabe H Yamamura H Komiyama M Endo S Tobi M Ohshima H Mano Y Hyodo M Kaneko T Otani S 《The Journal of General and Applied Microbiology》1997,43(4):225-230
Carbon material such as graphite and activated charcoal, but not diamond, causes the promotion of growth of certain bacteria under ordinarily non-permissive stress conditions over a distance of several centimeters. Bacillus carboniphilus under the stress of a high KCl concentration and high temperature responded to this remote effect of carbon material with enhanced growth, and thermophile bacterium Bacillus stearothermophilus responded similarly yet moderately under the stress of low temperature. The remote effect of carbon was caused by its activation with external energy, probably of electromagnetic nature, as this effect was markedly decreased by sheltering the experimental system with an iron or aluminum barrier. Carbon material probably transforms the external oscillatory pulses or radiation into a signal exerting, far-reaching, growth-promoting effect upon cells. The most plausible candidate of signals emitted from carbon was considered to be (ultra)sonic. 相似文献
993.
The complete nucleotide sequence of the chloroplast genome of Arabidopsis thaliana has been determined. The genome as a circular DNA composed of 154,478 bp containing a pair of inverted repeats of 26,264 bp, which are separated by small and large single copy regions of 17,780 bp and 84,170 bp, respectively. A total of 87 potential protein-coding genes including 8 genes duplicated in the inverted repeat regions, 4 ribosomal RNA genes and 37 tRNA genes (30 gene species) representing 20 amino acid species were assigned to the genome on the basis of similarity to the chloroplast genes previously reported for other species. The translated amino acid sequences from respective potential protein-coding genes showed 63.9% to 100% sequence similarity to those of the corresponding genes in the chloroplast genome of Nicotiana tabacum, indicating the occurrence of significant diversity in the chloroplast genes between two dicot plants. The sequence data and gene information are available on the World Wide Web database KAOS (Kazusa Arabidopsis data Opening Site) at http://www.kazusa.or.jp/arabi/. 相似文献
994.
Localization of a gene for benign adult familial myoclonic epilepsy to chromosome 8q23.3-q24.1. 下载免费PDF全文
M Mikami T Yasuda A Terao M Nakamura S Ueno H Tanabe T Tanaka T Onuma Y Goto S Kaneko A Sano 《American journal of human genetics》1999,65(3):745-751
Benign adult familial myoclonic epilepsy is an autosomal dominant idiopathic epileptic syndrome characterized by adult-onset tremulous finger movement, myoclonus, epileptic seizures, and nonprogressive course. It was recently recognized in Japanese families. In this study, we report that the gene locus is assigned to the distal long arm of chromosome 8, by linkage analysis in a large Japanese kindred with a maximum two-point LOD score of 4.31 for D8S555 at recombination fraction of 0 (maximum multipoint LOD score of 5.42 for the interval between D8S555 and D8S1779). Analyses of recombinations place the locus within an 8-cM interval, between D8S1784 and D8S1694, in which three markers, D8S1830, D8S555, and D8S1779, show no recombination with the phenotypes. Although three other epilepsy-related loci on chromosome 8q have been recognized-one on chromosome 8q13-21 (familial febrile convulsion) and two others on chromosome 8q24 (KCNQ3 and childhood absence epilepsy)-the locus assigned here is distinct from these three epilepsy-related loci. This study establishes the presence of a new epilepsy-related locus on 8q23.3-q24.11. 相似文献
995.
The complete nucleotide sequence of the hornwort (Anthoceros formosae) chloroplast genome: insight into the earliest land plants 总被引:4,自引:0,他引:4 下载免费PDF全文
Kugita M Kaneko A Yamamoto Y Takeya Y Matsumoto T Yoshinaga K 《Nucleic acids research》2003,31(2):716-721
It is generally believed that bryophytes are the earliest land plants. However, the phylogenetic relationships among bryophytes, including mosses, liverworts and hornworts, are not clearly resolved. To obtain more information on the earliest land plants, we determined the complete nucleotide sequence of the chloroplast genome from the hornwort Anthoceros formosae. The circular double-stranded DNA of 161 162 bp is the largest genome ever reported among land plant chloroplasts. It contains 76 protein, 32 tRNA and 4 rRNA genes and 10 open reading frames (ORFs), which are identical with the chloroplast genome of the other green plants analyzed. The major difference is a larger inverted repeat than that of the liverwort Marchantia, Anthoceros contains an excess of ndhB and rps7 genes and the 3′ exon of rps12. The genes matK and rps15, commonly found in the chloroplast genomes of land plants, are pseudogenes. The intron of rrn23 is the first finding in the known chloroplast genomes of land plants. A striking feature of the hornwort chloroplast is that more than half of the protein-coding genes have nonsense codons, which are converted into sense codons by RNA editing. Maximum-likelihood (ML) analysis, based on 11 518 amino acid sites of 52 proteins encoded in the chloroplast genomes of the green plants, placed liverworts as the sister to all other land plants. 相似文献
996.
Dendritic cells are important for the induction of T-lymphocyte-mediated immunity by acting as antigen-presenting cells. We
have previously reported that dendritic cells are prevalent in the chronic non-expanding phase of rat apical periodontitis.
To characterize these cells further, immunoelectron microscopy with three dendritic cell markers (CD11c, OX6, OX62) was conducted
for samples from rat models of apical periodontitis. Dendritic cells were divided into two types (type I or type II). Most
of the type I dendritic cells expressed CD11c, showed an irregular large profile, had typical cytoplasmic processes, and were
recognized as the major dendritic cell population. Most of the type II dendritic cells expressed OX62, showed oval small profiles
with a few thin short processes, and were sometimes observed infiltrating from blood vessels. Cell-to-cell contacts between
type I dendritic cells and lymphocytes were the most frequently observed associations. These results suggest that dendritic
cells are composed of heterogeneous populations that exhibit different phenotypes, morphologies, and maturation/differentiation/activation.
This study was supported by Grants-in-Aid for Scientific Research (no. 11470402 to T.O., and nos. 15791091 and 18791393 to
T.K.) from the Japan Society for the Promotion of Sciences. 相似文献
997.
One of the major goals in evolutionary developmental biology is to understand the relationship between gene regulatory networks and the diverse morphologies and their functionalities. Are the diversities solely triggered by random events, or are they inevitable outcomes of an interplay between evolving gene networks and natural selection? Segmentation in arthropod embryogenesis represents a well-known example of body plan diversity. Striped patterns of gene expression that lead to the future body segments appear simultaneously or sequentially in long and short germ-band development, respectively. Moreover, a combination of both is found in intermediate germ-band development. Regulatory genes relevant for stripe formation are evolutionarily conserved among arthropods, therefore the differences in the observed traits are thought to have originated from how the genes are wired. To reveal the basic differences in the network structure, we have numerically evolved hundreds of gene regulatory networks that produce striped patterns of gene expression. By analyzing the topologies of the generated networks, we show that the characteristics of stripe formation in long and short germ-band development are determined by Feed-Forward Loops (FFLs) and negative Feed-Back Loops (FBLs) respectively, and those of intermediate germ-band development are determined by the interconnections between FFL and negative FBL. Network architectures, gene expression patterns and knockout responses exhibited by the artificially evolved networks agree with those reported in the fly Drosophila melanogaster and the beetle Tribolium castaneum. For other arthropod species, principal network architectures that remain largely unknown are predicted. Our results suggest that the emergence of the three modes of body segmentation in arthropods is an inherent property of the evolving networks. 相似文献
998.
999.
Shunsuke Itai Shinji Yamada Mika K. Kaneko Masato Sano Takuro Nakamura Miyuki Yanaka Saori Handa Kayo Hisamatsu Yoshimi Nakamura Yoshikazu Furusawa Masato Fukui Tomokazu Ohishi Manabu Kawada Hiroyuki Harada Yukinari Kato 《Biochemistry and Biophysics Reports》2018
Oral cancers constitute approximately 2% of all cancers, with the most common histological type being oral squamous cell carcinoma (OSCC), representing 90% of oral cancers. Although diagnostic technologies and therapeutic techniques have progressed, the survival rate of patients with OSCC is still 60%, whereas the incidence rate has increased. Podocalyxin (PODXL) is a highly glycosylated type I transmembrane protein that is detected in normal tissues such as heart, breast, and pancreas as well as in many cancers, including lung, renal, breast, colorectal, and oral cancers. This glycoprotein is associated with the progression, metastasis, and poor outcomes of oral cancers. PODXL overexpression was strongly detected using our previously established anti-PODXL monoclonal antibody (mAb), PcMab-47, and its mouse IgG2a-type, 47-mG2a. In previous studies, we also generated PODXL-knock out (PODXL-KO) cell lines using SAS OSCC cell lines, in order to investigate the function of PODXL in the proliferation of oral cancer cells. The growth of SAS/PODXL-KO cell lines was observed to be lower than that of parental SAS cells. For this study, PODXL-KO OSCC cell lines were generated using HSC-2 cells, and the role of PODXL in the growth of OSCC cell lines in vitro was assessed. Decreased growth was observed for HSC-2/PODXL-KO cells compared with HSC-2 parental cells. The influence of PODXL on tumor growth of OSCC was also investigated in vivo, and both the tumor volume and the tumor weight were observed to be significantly lower for HSC-2/PODXL-KO than that for HSC-2 parental cells. These results, taken together, indicate that PODXL plays an important role in tumor growth, both in vitro and in vivo. 相似文献
1000.
Changes in concentrations of bioactive and immunoreactive (ir-) inhibin, estradiol-17 beta, progesterone, LH, and FSH in peripheral blood were determined in cows induced to superovulate with eCG. The pattern of follicular growth was also characterized by daily ultrasonographic examination. Hormonal profiles and follicular development during the intact estrous cycle of the same animals before eCG treatment served as controls. Equine CG increased the number of follicles of various sizes (small, greater than or equal to 4 less than 7, medium, greater than or equal to 7 less than 10; large, greater than or equal to 10 mm in diameter) by 4 days after administration. The second growth of large follicles occurred within 1 day after superovulation. Inhibin bioactivity in jugular vein blood was detectable 48 h after eCG injection (44 h before LH peak), whereas it was not detected before administration of eCG or during control cycles. Circulating levels of bioactive inhibin further increased during the two waves of growth of large follicles. The highest activity of inhibin was noted at the time of the preovulatory LH peak (0 h). Thereafter, bioactivity of inhibin in peripheral plasma dropped from 0 to 24 h after the LH peak, and the activity increased again at 72 h compared to the value at -44 h. Plasma levels of ir-inhibin showed a pattern similar to changes in bioactive inhibin in the eCG-treated cows. Plasma concentrations of estradiol-17 beta also increased concomitantly with two waves of growth of large follicles. There was no correlation between plasma levels of progesterone and inhibin.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献