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121.
We have cloned and characterized a novel splice variant of mouse GMx33alpha/Golgi-associated protein of 34 kDa (GPP34), hereby designated GMx33alphaV/GPP34V. This splice variant skips the second and third exons, and the resulting frame shift generates a stop codon in the fourth exon. GMx33alphaV/GPP34V is comprised of 81 amino acid residues derived from the N-terminal end of the full length protein and corresponds to approximately one-third of the full length GMx33alpha/GPP34 sequence with a calculated molecular mass of 8900. In contrast to GMx33alpha/GPP34 mRNA which is expressed at similar levels in various tissues, GMx33alphaV/GPP34V mRNA was differentially expressed when examined by RT-PCR. Compared to other tissues, skeletal muscle showed relatively strong expression of GMx33alphaV/GPP34V mRNA. This splice variant cDNA was also detected in a human cell line.  相似文献   
122.
Phenolic glucosides having radical scavenging activity were examined from the fraction eluted with 20% methanol on Amberlite XAD-2 resin applied to lemon (Citrus limon) juice by using reversed phase chromatography. Four phenolic glucosides were identified as 1-feruloyl-beta-D-glucopyranoside, 1-sinapoyl-beta-D-glucopyranoside, 6,8-di-C-glucosylapigenin and 6,8-di-C-glucosyldiosmetin by (1)H-NMR, (13)C-NMR, and MS analyses. They exhibited radical scavenging activity for 1,1-diphenyl-2-picrylhydrazyl (DPPH) and superoxide, although the activity was low in comparison with eriocitrin, a potent antioxidant in lemon fruit, and the eriodictyol of its aglycone. The phenolic compounds in lemon juice were examined for their suppressive effect on the expression of blood adhesion molecules by measuring the expression of intercellular adhesion molecule-1 (ICAM-1) in human umbilical vein endothelial cells (HUVECs) induced by necrosis factor-alpha (TNF-alpha). 6,8-Di-C-glucosylapigenin, apigenin, and diosmentin of the flavones were found to significantly suppress the expression of ICAM-1 at 10 muM (P<0.05). The phenolic glucosides isolated in this study were contained in comparative abundance in daidai (Citrus aurantium) and niihime (Citrus unshiu x Citrus tachibana) among the sour citrus juices.  相似文献   
123.
Phenolics, formed via a complex phenylpropanoid pathway, are important defensive agents in plants and are strongly affected by nitrogen (N) fertilization. Proanthocyanidins (PAs) are one possible endpoint of the phenylpropanoid pathway, and anthocyanidin reductase (ANR) represents a key enzyme in PA biosynthesis. In this study, the expression of silver birch (Betula pendula) anthocyanidin reductase BpANR was inhibited using the RNA interference (RNAi) method, in three consequent BpANR RNAi (ANRi birches) lines. The growth, the metabolites of the phenylpropanoid pathway, and the number of resin glands of the ANRi birches were studied when grown at two N levels. ANRi birches showed decreased growth and reduction in PA content, while the accumulation of total phenolics in both stems and leaves increased. Moreover, ANRi birches produced more resin glands than did wild‐type (WT) birches. The response of ANRi birches to N depletion varied compared with that of WT birches, and in particular, the concentrations of some phenolics in stems increased in WT birches and decreased in ANRi birches. Because the inhibition of PAs biosynthesis via ANR seriously affected birch growth and resulted in accumulation of the precursors, the native level of PAs in plant tissues is assumed to be the prerequisite for normal plant growth. This draws attention to the real plant developmental importance of PAs in plant tissues.  相似文献   
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125.
Injury in adult tissue generally reactivates developmental programs to foster regeneration, but it is not known whether this paradigm applies to growing tissue. Here, by employing blisters, we show that epidermal wounds heal at the expense of skin development. The regenerated epidermis suppresses the expression of tissue morphogenesis genes accompanied by delayed hair follicle (HF) growth. Lineage tracing experiments, cell proliferation dynamics, and mathematical modeling reveal that the progeny of HF junctional zone stem cells, which undergo a morphological transformation, repair the blisters while not promoting HF development. In contrast, the contribution of interfollicular stem cell progeny to blister healing is small. These findings demonstrate that HF development can be sacrificed for the sake of epidermal wound regeneration. Our study elucidates the key cellular mechanism of wound healing in skin blistering diseases.  相似文献   
126.
We identified a fused heteroaromatic amido structure based on the phenanthridine skeleton as a superior scaffold for candidate drugs with potent anti-HCV activity. Among the compounds synthesized, a phenanthridine analogue with a 1,3-dioxolyl group (24) possessed the most potent anti-HCV activity (EC(50) value: 50 nM), with acceptable cytotoxicity. The structural development and structure-activity relationships of these compounds are described.  相似文献   
127.
The calcium-sensing receptor antagonist (CaSR) has been recognized as a promising target of anabolic agents for treating osteoporosis. In the course of developing a new drug candidate for osteoporosis, we found tetrahydropyrazolopyrimidine derivative 1 to be an orally active CaSR antagonist that stimulated transient PTH secretion in rats. However, compound 1 showed poor physical and chemical stability. In order to work out this compound's chemical stability and further understand its in vivo efficacy, we focused on modifying the 2-position of the tetrahydropyrazolopyrimidine. As a result of chemical modification, we discovered (5R)-N-[1-ethyl-1-(4-ethylphenyl)propyl]-2,7,7-trimethyl-5-phenyl-4,5,6,7-tetrahydropyrazolo[1,5-a]pyrimidine-3-carboxamide monotosylate 10m (TAK-075), which showed improved solubility, chemical stability, and in vivo efficacy. Furthermore, we describe that evaluating the active metabolite is important during repeated treatment with short-acting CaSR antagonists.  相似文献   
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129.
Testosterone concentrations in men are associated with cardiovascular morbidity, osteoporosis, and mortality and are affected by age, smoking, and obesity. Because of serum testosterone''s high heritability, we performed a meta-analysis of genome-wide association data in 8,938 men from seven cohorts and followed up the genome-wide significant findings in one in silico (n = 871) and two de novo replication cohorts (n = 4,620) to identify genetic loci significantly associated with serum testosterone concentration in men. All these loci were also associated with low serum testosterone concentration defined as <300 ng/dl. Two single-nucleotide polymorphisms at the sex hormone-binding globulin (SHBG) locus (17p13-p12) were identified as independently associated with serum testosterone concentration (rs12150660, p = 1.2×10−41 and rs6258, p = 2.3×10−22). Subjects with ≥3 risk alleles of these variants had 6.5-fold higher risk of having low serum testosterone than subjects with no risk allele. The rs5934505 polymorphism near FAM9B on the X chromosome was also associated with testosterone concentrations (p = 5.6×10−16). The rs6258 polymorphism in exon 4 of SHBG affected SHBG''s affinity for binding testosterone and the measured free testosterone fraction (p<0.01). Genetic variants in the SHBG locus and on the X chromosome are associated with a substantial variation in testosterone concentrations and increased risk of low testosterone. rs6258 is the first reported SHBG polymorphism, which affects testosterone binding to SHBG and the free testosterone fraction and could therefore influence the calculation of free testosterone using law-of-mass-action equation.  相似文献   
130.

Background

Much of our understanding of the age-related progression of systolic blood pressure (SBP) comes from cross-sectional data, which do not directly capture within-individual change. We estimated life course trajectories of SBP using longitudinal data from seven population-based cohorts and one predominantly white collar occupational cohort, each from the United Kingdom and with data covering different but overlapping age periods.

Methods and Findings

Data are from 30,372 individuals and comprise 102,583 SBP observations spanning from age 7 to 80+y. Multilevel models were fitted to each cohort. Four life course phases were evident in both sexes: a rapid increase in SBP coinciding with peak adolescent growth, a more gentle increase in early adulthood, a midlife acceleration beginning in the fourth decade, and a period of deceleration in late adulthood where increases in SBP slowed and SBP eventually declined. These phases were still present, although at lower levels, after adjusting for increases in body mass index though adulthood. The deceleration and decline in old age was less evident after excluding individuals who had taken antihypertensive medication. Compared to the population-based cohorts, the occupational cohort had a lower mean SBP, a shallower annual increase in midlife, and a later midlife acceleration. The maximum sex difference was found at age 26 (+8.2 mm Hg higher in men, 95% CI: 6.7, 9.8); women then experienced steeper rises and caught up by the seventh decade.

Conclusions

Our investigation shows a general pattern of SBP progression from childhood in the UK, and suggests possible differences in this pattern during adulthood between a general population and an occupational population. Please see later in the article for the Editors'' Summary  相似文献   
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