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71.
Muscle glycogen synthase (GYS1) is the rate-limiting enzyme in glycogen synthesis, and its activity is regulated by the phosphorylation states of certain amino acid residues encoded by the GYS1 gene. In the present study, the authors molecularly characterized the full-length equine GYS1 (eGYS1) cDNA and found that it contains a less common polyadenylation signal (AATACA). An amino acid alignment with other mammalian GYS1 showed that the phosphorylation sites in eGYS1 are completely conserved. Genomic DNA analysis revealed that the equine-specific substitutions (Glu 16 Asp and Ala 252 Thr) were completely conserved among six equine species. The tissue expression profiles of eGYS1, equine type II hexokinase (eHKII) and muscle-type phosphofructokinase (ePFKM) were determined by real-time PCR and western blot analysis. The mRNA expression level of eGYS1 was significantly higher in the cervical muscle as compared to other tissues. The cervical muscle and heart tissue samples contained a broad range of eGYS1 protein bands that appeared to reflect multiple phosphorylation states. eHKII was predominately expressed only in the cervical muscle; unlike its expression in other mammals, eHKII was not substantially expressed in the insulin-responsive heart or adipose tissue of horse. The expression level of ePFKM mRNA was significantly higher in the heart than in the cervical muscle, which differs from the PFKM expression pattern of other mammals. These tissue expression profiles are fundamental for the understanding of equine glucose metabolism.  相似文献   
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'La France' pear ( Pyrus communis L.) fruit stored at 1°C for 1 month (short-term storage) before transfer to 20°C softened and developed a melting texture during ripening, whereas fruit stored for 5 months (long-term storage) before transfer to 20°C softened but did not develop a melting texture. To clarify the mechanisms involved in fruit softening and textural changes, the cDNAs encoding cell-wall hydrolases were isolated by RT-PCR, and their expression and localization were investigated in 'La France' pears. Genes encoding three polygalacturonases (PG; EC 3.2.1.15), four pectin methylesterases (PME; EC 3.1.1.11), one α -arabinofuranosidase (ARF; EC 3.2.1.55), three β -galactosidases (GAL; EC 3.2.1.23), and two endo-1,4- β - d -glucanases (Cel; EC 3.2.1.4) were isolated. Among these 13 isolated genes, PcPG1 was the only gene for which the mRNA expression levels increased in both the short- and long-term stored fruits. This suggested that PcPG1 is involved in fruit softening rather than in the development of the melting texture. In contrast, the expression levels of PcPG3 , PcPME1 , PcPME2 , PcPME3 , PcGAL1 , PcGAL2 , and PcCel2 increased during ripening only in the short-term stored fruit. These genes might thus be involved in the development of the melting texture.  相似文献   
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Two foraminiferal associations comprising only arenaceous species define two distinct environments in a 340 m-long mangrove transect at Cardoso Island, Trapandé Bay (Cananéia-Iguape estuarine system, SP, Brazil). The “lower muddy flat” (LMF), from the outer mangrove fringe inwards towards land (100 m), is positioned in the lower plain between 0.04 and 0.23 m above the mean sea level (msl), and remains subaerially exposed between 48.5 and 65.6% of the time. This environment is characterized by higher foraminiferal diversity and evenness (McIntosh's D = 0.54 ± 0.21 and Pielou's E = 0.68 ± 0.25, respectively) and is dominated by Arenoparrella mexicana and Trochammina inflata, and to a lesser extent by Ammotium directum and Textularia earlandi. The mangrove plant of this segment is a Rhizophoretum with average height of 8.4 ± 1.2 m. The sediment is characterized by higher concentration of organic matter (93.5 ± 32.3 g dm−3) and metals (e.g. V = 53.4 ± 21.8 ppm and Zn = 46.4 ± 21.3 ppm). The “upper sandy flat” (USF), 240 m wide along the transect, is positioned in the upper plain between 0.28 and 0.89 m above the msl, and remains subaerially exposed between 69.7 and 98.5% of the time. This environment is characterized by a lower diversity and evenness (D = 0.33 ± 0.17 and E = 0.49 ± 0.20, respectively). The association is dominated by species T. inflata and Miliammina fusca. The Rhizophoretum exhibits a lower average height of 3.6 ± 0.6 m. The sediment is poorer in organic matter (39.3 ± 15.0 g dm−3) and metals (e.g. V = 13.0 ± 6.8 ppm and Zn = 6.9 ± 3.7 ppm). Whereas “elongate” tests (uniserial, biserial and planospiral followed by a uniserial portion) are restricted to the LMF, “spiraled” species dominate the USF. Subaerial exposure time seems to exert a primary influence on species distribution, in addition to salinity and sediment type. Species may be adapted to different exposure times, a factor dependent on their position on the intertidal zone and the tidal regime, which should be taken into account in relative sea level reconstructions based on intertidal foraminifera. These patterns have important implications for studies investigating the ecology and paleoecology of foraminifera and subtle fluctuations in relative sea level during the Quaternary.  相似文献   
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We previously reported that mutation of galE in Porphyromonas gingivalis has pleiotropic effects, including a truncated lipopolysaccharide (LPS) O-antigen and deglycosylation of the outer membrane protein OMP85 homolog. In the present study, further analysis of the galE mutant revealed that it produced little or no outer membrane vesicles (OMVs). Using three mouse antisera raised against whole cells of the P. gingivalis wild type strain, we performed ELISAs to examine the reactivity of these antisera with whole cells of the wild type or the galE mutant. All three antisera had significantly lower reactivity against the galE mutant compared to wild type. OMVs, but not LPS, retained the immunodominant determinant of P. gingivalis, as determined by ELISAs (with wild type LPS or OMVs as antigen) and absorption assays. In addition, we assessed the capacity of OMVs as a vaccine antigen by intranasal immunization to BALB/c mice. Synthetic double-stranded RNA polyriboinosinic polyribocytidylic acid [Poly (I∶C)], an agonist of Toll-like receptor 3 (TLR3), was used as the mucosal adjuvant. Vaccination with OMV elicited dramatically high levels of P. gingivalis-specific IgA in nasal washes and saliva, as well as serum IgG and IgA. In conclusion, the OMVs of P. gingivalis have an important role in mucosal immunogenicity as well as in antigenicity. We propose that P. gingivalis OMV is an intriguing immunogen for development of a periodontal disease vaccine.  相似文献   
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The purpose of the study was to evaluate the quality of Toki-shakuyaku-san extract granules (TJ-23) using chemiluminescence (CL). A linear relationship was obtained between the log value of the CL of TJ-23 and the reaction temperature. An excellent correlation (r= 0.999) was found between the slope of this curve (ΔA) and the colour intensity due to the browning reaction occurring at the early stage of the Maillard reaction.  相似文献   
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