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991.
992.
Hepatocyte nuclear factor 4alpha contributes to thyroid hormone homeostasis by cooperatively regulating the type 1 iodothyronine deiodinase gene with GATA4 and Kruppel-like transcription factor 9 下载免费PDF全文
993.
Raman H Ryan PR Raman R Stodart BJ Zhang K Martin P Wood R Sasaki T Yamamoto Y Mackay M Hebb DM Delhaize E 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2008,116(3):343-354
Allele diversities of four markers specific to intron three, exon four and promoter regions of the aluminum (Al) resistance
gene of wheat (Triticum aestivum L.) TaALMT1 were compared in 179 common wheat cultivars used in international wheat breeding programs. In wheat cultivars released during
the last 93 years, six different promoter types were identified on the basis of allele size. A previous study showed that
Al resistance was not associated with a particular coding allele for TaALMT1 but was correlated with blocks of repeated sequence upstream of the coding sequence. We verified the linkage between these
promoter alleles and Al resistance in three doubled haploid and one intercross populations segregating for Al resistance.
Molecular and pedigree analysis suggest that Al resistance in modern wheat germplasm is derived from several independent sources.
Analysis of a population of 278 landraces and subspecies of wheat showed that most of the promoter alleles associated with
Al resistance pre-existed in Europe, the Middle East and Asia prior to dispersal of cultivated germplasm around the world.
Furthermore, several new promoter alleles were identified among the landraces surveyed. The TaALMT1 promoter alleles found within the spelt wheats were consistent with the hypothesis that these spelts arose on several independent
occasions from hybridisations between non-free-threshing tetraploid wheats and Al-resistant hexaploid bread wheats. The strong
correlation between Al resistance and Al-stimulated malate efflux from the root apices of 49 diverse wheat genotypes examined
was consistent with the previous finding that Al resistance in wheat is conditioned primarily by malate efflux. These results
demonstrate that the markers based on intron, exon and promoter regions of TaALMT1 can trace the inheritance of the Al resistance locus within wheat pedigrees and track Al resistance in breeding programmes.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
994.
995.
Tanisaka H Kizaka-Kondoh S Makino A Tanaka S Hiraoka M Kimura S 《Bioconjugate chemistry》2008,19(1):109-117
Nonionic amphiphilic copolypeptides, which were composed of hydrophilic poly(sarcosine) and hydrophobic poly(gamma-methyl L-glutamate) blocks, were synthesized with varying chain lengths of the blocks. The polypeptides having a suitable hydrophilic and hydrophobic balance were found to form vesicular assemblies of 100 nm size in buffer, which was evidenced by the TEM observation, the DLS analysis, and the encapsulation experiment. The genuine peptide vesicles, peptosomes, were labeled with a near-infrared fluorescence (NIRF) probe. In vivo retention in blood experiment showed long circulation of the peptosome in rat blood as stable as the PEGylated liposome. NIRF imaging of a small cancer on mouse by using the peptosome as a nanocarrier was successful due to the EPR effect of the peptosome. Peptosome is shown here as a novel excellent nanocarrier for molecular imaging. 相似文献
996.
997.
Weight-bearing bone is constantly adapting its structure and function to mechanical environments. Loading through routine exercises stimulates bone formation and prevents bone loss, but unloading through bed rest and cast immobilization as well as exposure to weightlessness during spaceflight reduces its mass and strength. In order to elucidate the mechanism underlying unloading-driven bone adaptation, ground-based in vitro and in vivo analyses have been conducted using rotating cell culturing and hindlimb suspension. Focusing on gene expression studies in osteoblasts and hindlimb suspension studies, this minireview introduces our recent understanding on bone homeostasis under weightlessness in space. Most of the existing data indicate that unloading has the opposite effects to loading through common signaling pathways. However, a question remains as to whether any pathway unique to unloading (and not to loading) may exist. 相似文献
998.
Hiroki Nishimura Gen Komaki Tetsuya Ando Toshihiro Nakahara Takakazu Oka Keisuke Kawai Toshihiko Nagata Aya Nishizono Yuri Okamoto Kenjiro Okabe Masanori Koide Chikara Yamaguchi Satoshi Saito Kazuyoshi Ohkuma Katsutaro Nagata Tetsuro Naruo Masato Takii Nobuo Kiriike Toshio Ishikawa 《BioPsychoSocial medicine》2008,2(1):1-8
Background
Over the last five to ten years there has been an increase in psychosomatic complaints (PSC) in Swedish children. The objective of the study was to examine the relation between PSC and sense of coherence (SOC). 相似文献999.
He XS Holmes TH Sasaki S Jaimes MC Kemble GW Dekker CL Arvin AM Greenberg HB 《PloS one》2008,3(7):e2574
Background
Factors affecting immune responses to influenza vaccines have not been studied systematically. We hypothesized that T-cell and antibody responses to the vaccines are functions of pre-existing host immunity against influenza antigens.Methodology/Principal Findings
During the 2004 and 2005 influenza seasons, we have collected data on cellular and humoral immune reactivity to influenza virus in blood samples collected before and after immunization with inactivated or live attenuated influenza vaccines in healthy children and adults. We first used cross-validated lasso regression on the 2004 dataset to identify a group of candidate baseline correlates with T-cell and antibody responses to vaccines, defined as fold-increase in influenza-specific T-cells and serum HAI titer after vaccination. The following baseline parameters were examined: percentages of influenza-reactive IFN-γ+ cells in T and NK cell subsets, percentages of influenza-specific memory B-cells, HAI titer, age, and type of vaccine. The candidate baseline correlates were then tested with the independent 2005 dataset. Baseline percentage of influenza-specific IFN-γ+ CD4 T-cells was identified as a significant correlate of CD4 and CD8 T-cell responses, with lower baseline levels associated with larger T-cell responses. Baseline HAI titer and vaccine type were identified as significant correlates for HAI response, with lower baseline levels and the inactivated vaccine associated with larger HAI responses. Previously we reported that baseline levels of CD56dim NK reactivity against influenza virus inversely correlated with the immediate T-cell response to vaccination, and that NK reactivity induced by influenza virus depended on IL-2 produced by influenza-specific memory T-cells. Taken together these results suggest a novel mechanism for the homeostasis of virus-specific T-cells, which involves interaction between memory helper T-cells, CD56dim NK and DC.Significance
These results demonstrate that assessment of baseline biomarkers may predict immunologic outcome of influenza vaccination and may reveal some of the mechanisms responsible for variable immune responses following vaccination and natural infection. 相似文献1000.
Saori Morino Tatsuya Kondo Kazunari Sasaki Hironori Adachi Mary Ann Suico Erika Sekimoto Tomoko Matsuda Tsuyoshi Shuto Eiichi Araki Hirofumi Kai 《PloS one》2008,3(12)
Low-intensity electrical current (or mild electrical stimulation; MES) influences signal transduction and activates phosphatidylinositol-3 kinase (PI3K)/Akt pathway. Because insulin resistance is characterized by a marked reduction in insulin-stimulated PI3K-mediated activation of Akt, we asked whether MES could increase Akt phosphorylation and ameliorate insulin resistance. In addition, it was also previously reported that heat shock protein 72 (Hsp72) alleviates hyperglycemia. Thus, we applied MES in combination with heat shock (HS) to in vitro and in vivo models of insulin resistance. Here we show that 10-min treatment with MES at 5 V (0.1 ms pulse duration) together with HS at 42°C increased the phosphorylation of insulin signaling molecules such as insulin receptor substrate (IRS) and Akt in HepG2 cells maintained in high-glucose medium. MES (12 V)+mild HS treatment of high fat-fed mice also increased the phosphorylation of insulin receptor β subunit (IRβ) and Akt in mice liver. In high fat-fed mice and db/db mice, MES+HS treatment for 10 min applied twice a week for 12–15 weeks significantly decreased fasting blood glucose and insulin levels and improved insulin sensitivity. The treated mice showed significantly lower weight of visceral and subcutaneous fat, a markedly improved fatty liver and decreased size of adipocytes. Our findings indicated that the combination of MES and HS alleviated insulin resistance and improved fat metabolism in diabetes mouse models, in part, by enhancing the insulin signaling pathway. 相似文献