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51.
Takahito Tamai Osamu Yamaguchi Shungo Hikoso Toshihiro Takeda Manabu Taneike Takafumi Oka Jota Oyabu Tomokazu Murakawa Hiroyuki Nakayama Yoshihiro Uno Kyoji Horie Kazuhiko Nishida Nahum Sonenberg Ajay M. Shah Junji Takeda Issei Komuro Kinya Otsu 《The Journal of biological chemistry》2013,288(14):10176-10187
Cardiomyocytes proliferate during fetal life but lose their ability to proliferate soon after birth and further increases in cardiac mass are achieved through an increase in cell size or hypertrophy. Mammalian target of rapamycin complex 1 (mTORC1) is critical for cell growth and proliferation. Rheb (Ras homologue enriched in brain) is one of the most important upstream regulators of mTORC1. Here, we attempted to clarify the role of Rheb in the heart using cardiac-specific Rheb-deficient mice (Rheb−/−). Rheb−/− mice died from postnatal day 8 to 10. The heart-to-body weight ratio, an index of cardiomyocyte hypertrophy, in Rheb−/− was lower than that in the control (Rheb+/+) at postnatal day 8. The cell surface area of cardiomyocytes isolated from the mouse hearts increased from postnatal days 5 to 8 in Rheb+/+ mice but not in Rheb−/− mice. Ultrastructural analysis indicated that sarcomere maturation was impaired in Rheb−/− hearts during the neonatal period. Rheb−/− hearts exhibited no difference in the phosphorylation level of S6 or 4E-BP1, downstream of mTORC1 at postnatal day 3 but showed attenuation at postnatal day 5 or 8 compared with the control. Polysome analysis revealed that the mRNA translation activity decreased in Rheb−/− hearts at postnatal day 8. Furthermore, ablation of eukaryotic initiation factor 4E-binding protein 1 in Rheb−/− mice improved mRNA translation, cardiac hypertrophic growth, sarcomere maturation, and survival. Thus, Rheb-dependent mTORC1 activation becomes essential for cardiomyocyte hypertrophic growth after early postnatal period. 相似文献
52.
Yasuhito Hamaguchi Manabu Fujimoto Takashi Matsushita Kenzo Kaji Kazuhiro Komura Minoru Hasegawa Masanari Kodera Eiji Muroi Keita Fujikawa Mariko Seishima Hidehiro Yamada Ryo Yamada Shinichi Sato Kazuhiko Takehara Masataka Kuwana 《PloS one》2013,8(4)
Objective
To identify similarities and differences in the clinical features of adult Japanese patients with individual anti-aminoacyl-tRNA synthetase antibodies (anti-ARS Abs).Methods
This was a retrospective analysis of 166 adult Japanese patients with anti-ARS Abs detected by immunoprecipitation assays. These patients had visited Kanazawa University Hospital or collaborating medical centers from 2003 to 2009.Results
Anti-ARS Ab specificity included anti-Jo-1 (36%), anti-EJ (23%), anti-PL-7 (18%), anti-PL-12 (11%), anti-KS (8%), and anti-OJ (5%). These anti-ARS Abs were mutually exclusive, except for one serum Ab that had both anti-PL-7 and PL-12 reactivity. Myositis was closely associated with anti-Jo-1, anti-EJ, and anti-PL-7, while interstitial lung disease (ILD) was correlated with all 6 anti-ARS Abs. Dermatomyositis (DM)-specific skin manifestations (heliotrope rash and Gottron’s sign) were frequently observed in patients with anti-Jo-1, anti-EJ, anti-PL-7, and anti-PL-12. Therefore, most clinical diagnoses were polymyositis or DM for anti-Jo-1, anti-EJ, and anti-PL-7; clinically amyopathic DM or ILD for anti-PL-12; and ILD for anti-KS and anti-OJ. Patients with anti-Jo-1, anti-EJ, and anti-PL-7 developed myositis later if they had ILD alone at the time of disease onset, and most patients with anti-ARS Abs eventually developed ILD if they did not have ILD at disease onset.Conclusion
Patients with anti-ARS Abs are relatively homogeneous. However, the distribution and timing of myositis, ILD, and rashes differ among patients with individual anti-ARS Abs. Thus, identification of individual anti-ARS Abs is beneficial to define this rather homogeneous subset and to predict clinical outcomes within the “anti-synthetase syndrome.” 相似文献53.
Conserved roles of fibroblast growth factor receptor 2 signaling in the regulation of inner cell mass development in bovine blastocysts 下载免费PDF全文
54.
Manabu Fukui Jungin Suh Yoshitaka Yonezawa Yoshikuni Urushigawa 《Ecological Research》1997,12(2):201-209
To clarify the anaerobic microbial interactions in the process of carbon mineralization in marine eutrophic environments,
the microbial sulfate reduction and methane production rates were examined in coastal marine sediments of Ise Bay, Japan,
in autumn 1990. Sulfate reduction rates (51–210 nmol ml−1 day−1 at 24°C) were much higher than the methane production ones (<1.78 nmol ml−1 day−1) in the surface sediments (top 2 cm) at the six stations surveyed (water depth: 10.7–23.3 m). Substrates for sulfate-reducing
bacteria (SRB) were estimated after the addition of a specific inhibitor for SRB (20 mmol l−1 molybdate) into the sediment slurry, from the substrate accumulation rates. In the presence of the inhibitor, sulfate reduction
was completely stopped and volatile fatty acids (mainly acetate) were accumulated, although hydrogen was not. Methane production
occurred markedly accompanied by consumption of the accumulated acetate from the third day after the addition of molybdate.
The maximum rate of methane production was 1.2–1.9 μmol ml−1 day−1, which was similar to those in highly polluted freshwater sediments such as the Tama River, Tokyo, Japan. These results show
that acetate is a common major substrate for sulfate reduction and methane production, and SRB competitively inhibit potential
acetoclastic methanogenesis in coastal sediments. Methanogens may potentially inhabit the sediments at low levels of population
density and activity. 相似文献
55.
Satoshi Ogawa Milton Orlando Valencia Mathias Lorieux Juan David Arbelaez Susan McCouch Manabu Ishitani Michael Gomez Selvaraj 《Acta Physiologiae Plantarum》2016,38(4):103
Improved root system architecture can enhance agronomic performance by increasing water and nitrogen (N) acquisition efficiency. However, little is known about interaction between root system architecture and agronomic performance under field environments. To gain a better understanding about the genetic basis of these relationships, we evaluated a set of chromosome segment substitution lines (CSSLs) derived from crosses between a tropical japonica rice cultivar ‘Curinga’ and a wild species Oryza rufipogon accession IRGC105491. Root system architectural traits were investigated using the CSSLs at 40 days old seedlings using the root basket method under hydroponic conditions, and agronomic performances were also tested under field conditions with different N treatments. Agronomic performances were computed as the ratio of a trait value under low to high N treatments, including grain yield and biomass yield as nitrogen-deficiency tolerance (NDT) traits. Root architecture and NDT trait QTLs were mapped using 238 SNP marker loci. A total of 13 QTLs for root system architectural, NDT and morpho-physiological traits were identified on chromosomes 1, 3, 4, 5, 7, 8, 9, 10 and 12. Interestingly, a QTL for deeper root number was identified the region of SNP markers between id1012330 and id1021697 on chromosome 1 under hydroponic conditions overlapped with a QTL for NDT trait of relative grain yield (qRGY1). These results suggest that deeper root trait is helpful to maintain grain yield under nitrogen-deficient conditions. The QTL associated root architecture could potentially be used in future rice-breeding efforts to increase agronomic performance under nitrogen-deficient conditions. 相似文献
56.
Masabumi Funakoshi Manabu Tsuda Keigo Muramatsu Hiroshi Hatsuda Shinichi Morishita Toshiro Aigaki 《Biochemical and biophysical research communications》2011,(4):214
The insulin/insulin-like growth factor (IGF) and the target of rapamycin (TOR) signaling pathways are known to regulate lifespan in diverse organisms. However, only a limited number of genes involved in these pathways have been examined regarding their effects on lifespan. Through a gain-of-function screen in Drosophila, we found that overexpression of the wdb gene encoding a regulatory subunit of PP2A, and overexpression of the lkb1 gene encoding a serine/threonine kinase, reduced organ size and extended lifespan. Overexpression of wdb also reduced the level of phosphorylated AKT, while overexpression of lkb1 increased the level of phosphorylated AMPK and decreased the level of phosphorylated S6K. Taken together, our results suggest that wdb- and lkb1-dependent lifespan extension is mediated by downregulation of S6K, a downstream component of the insulin/IGF and TOR signaling pathways. 相似文献
57.
58.
Sumie S Kawaguchi T Kuromatsu R Takata A Nakano M Satani M Yamada S Niizeki T Torimura T Sata M 《PloS one》2011,6(11):e26840
Background
Adiponectin is shown to be inversely associated with development and progression of various cancers. We evaluated whether adiponectin level was associated with the prevalence and histological grade of hepatocellular carcinoma (HCC), and liver fibrosis in patients with hepatitis C virus (HCV) infection.Methods
A case-control study was conducted on 97 HCC patients (cases) and 97 patients (controls) matched for sex, Child-Pugh grade and platelet count in patients with HCV infection. The serum total and high molecular weight (HMW) adiponectin levels were measured by enzyme-linked immunosorbent assays and examined in their association with the prevalence of HCC. In addition, the relationship between these adiponectin levels and body mass index (BMI), progression of liver fibrosis, and histological grade of HCC was also evaluated. Liver fibrosis was assessed using the aspartate aminotransferase to platelet ratio index (APRI).Results
There were no significant differences in the serum total and HMW adiponectin levels between cases and controls. Moreover, there were no inverse associations between serum total and HMW adiponectin levels and BMI in both cases and controls. On the other hand, serum total and HMW adiponectin levels are positively correlated with APRI in both cases (r = 0.491, P<0.001 and r = 0.485, P<0.001, respectively) and controls (r = 0.482, P<0.001 and r = 0.476, P<0.001, respectively). Interestingly, lower serum total (OR 11.76, 95% CI: 2.97–46.66 [P<0.001]) and HMW (OR 10.24, CI: 2.80–37.40 [P<0.001] adiponectin levels were independent risk factors of worse histological grade of HCC.Conclusions
Our results suggested that serum total and HMW adiponectin levels were predictors of liver fibrosis, but not prevalence of HCC in patients with HCV infection. Moreover, low these adiponectin levels were significantly associated with worse histological grades. 相似文献59.
Okuyama Y Fujii N Wakabayashi M Kawakita A Ito M Watanabe M Murakami N Kato M 《Molecular biology and evolution》2005,22(2):285-296
Interspecific hybridization is one of the major factors leading to phylogenetic incongruence among loci, but the knowledge is still limited about the potential of each locus to introgress between species. By directly sequencing three DNA regions: chloroplast DNAs (matK gene and trnL-F noncoding region), the nuclear ribosomal external transcribed spacer (ETS) region, and internal transcribed spacer (ITS) regions, we construct three phylogenetic trees of Asian species of Mitella (Saxifragaceae), a genus of perennials in which natural hybrids are commonly observed. Within this genus, there is a significant topological conflict between chloroplast and nuclear phylogenies and also between the ETS and the ITS, which can be attributed to frequent hybridization within the lineage. Chloroplast DNAs show the most extensive introgression pattern, ITS regions show a moderate pattern, and the ETS region shows no evidence of introgression. Nonuniform concerted evolution best explains the difference in the introgression patterns between the ETS region and ITS regions, as the sequence heterogeneity of the ITS region within an individual genome is estimated to be twice that of an ETS in this lineage. Significant gene conversion patterns between two hybridizing taxa were observed in contiguous arrays of cloned ETS-ITS sequences, further confirming that only ITS regions have introgressed bidirectionally. The relatively slow concerted evolution in the ITS regions probably allows the coexistence of multiple alleles within a genome, whereas the strong concerted evolution in the ETS region rapidly eliminates heterogeneous alleles derived from other species, resulting in species delimitations highly concordant with those based on morphology. This finding indicates that the use of multiple molecular tools has the potential to reveal detailed organismal evolution processes involving interspecific hybridization, as an individual locus varies greatly in its potential to introgress between species. 相似文献
60.
Yoichiro?OkuboEmail author Osamu?Motohashi Norisuke?Nakayama Ken?Nishimura Rika?Kasajima Yohei?Miyagi Manabu?Shiozawa Emi?Yoshioka Masaki?Suzuki Kota?Washimi Kae?Kawachi Madoka?Nito Yoichi?Kameda Tomoyuki?Yokose 《Diagnostic pathology》2016,11(1):128