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501.
A quantitative genetic analysis was conducted on the amounts and distribution of variation of 20 floral, reproductive and
life history traits of a self-compatible perennial,Oxalis cornlculata L. (Oxalidaceae). This species comprises two floral morphs, homostyled and long-styled, with different breeding systems.
The hierarchical design of the experiments on three homostyled and three long-styled populations allowed partitioning of variation
into four levels of organization using nested ANOVAs. Seven of the 20 traits examined were differentiated between homostyled
and long-styled populations. Significant genetic variance components were detected in the major traits (114 of the 120 traits)
examined for six populations. Average values of variance components among families within a population across 20 traits for
homostyled populations were higher than those of long-styled populations. These responses likely reflect the consequences
of different levels of selfing and/or mixed mating on genetic variation in the two floral morphs ofO. corniculata. Pearson product-moment correlations for family means of seven traits selected were also calculated. Two groups of trait
combinations (i.e., between floral traits, and between reproductive and life history traits) showed significant family mean
correlation coefficients. The origins of these varlation patterns found in different populations ofO. corniculata are discussed in terms of the underlying selective regimes operating in each population. 相似文献
502.
Shin-ya Kawashiri Tomoki Origuchi Masataka Umeda Ayako Nishino Toshimasa Shimizu Shoichi Fukui Tomohiro Koga Naoki Iwamoto Kunihiro Ichinose Mami Tamai Hideki Nakamura Takahiro Maeda Mitsuhiro Kawano Motohisa Yamamoto Yasumori Izumi Atsushi Kawakami 《Arthritis research & therapy》2018,20(1):277
Background
The aim of this study was to identify fibrosis-related serological surrogate outcome measures in patients with immunoglobulin G4-related disease (IgG4-RD).Methods
This was a clinical observational study of 72 patients with untreated IgG4-RD from four institutions in Japan. The serum concentrations of growth differentiation factor 15 (GDF-15), CCL2, hyaluronic acid (HA), amino-terminal propeptide of type III procollagen (PIIINP), and tissue inhibitor of metalloproteinases 1 (TIMP-1) were measured by enzyme-linked immunosorbent assays. The enhanced liver fibrosis (ELF) score was calculated from the TIMP-1, PIIINP, and HA values. We evaluated associations between the values of these biomarkers and laboratory data, the IgG4-RD responder index (IgG4-RD RI) score, and organ involvements.Results
Compared with the 44 healthy controls, the patients with IgG4-RD showed significantly elevated serum concentrations of GDF-15, MCP-1, HA, PIIINP, and TIMP-1 and ELF scores. The patients’ serum concentrations of GDF-15, CCL2, HA, and TIMP-1 (but not PIIINP) were positively correlated with each other. Among them, serum GDF-15 most efficiently distinguished patients with IgG4-RD from healthy controls. Serum GDF-15 was not associated with the IgG4-RD RI score or the number of organ involvements but was independently associated with the presence of retroperitoneal fibrosis and with parotid gland involvement.Conclusions
We observed increased serological surrogate outcome measures of fibrosis in IgG4-RD. GDF-15 may precisely reflect the fibrotic degree in patients with IgG4-RD.503.
Shoichi Kuroda Yohei Kobashi Takahiro Oi Hideaki Amada Lisa Okumura-Kitajima Fusayo Io Koji Yamamto Hiroyuki Kakinuma 《Bioorganic & medicinal chemistry letters》2018,28(22):3534-3539
The design and synthesis of a novel class of low-absorbable SGLT1 inhibitors are described. To achieve low absorption in the new series, we performed an optimization study based on a strategy to increase TPSA. Fortunately, the optimization of an aglycon moiety and a side chain of the distal aglycon moiety led to the identification of compound 30b as a potent and low-absorbable SGLT1 inhibitor. Compound 30b showed a desirable PK profile in Sprague-Dawley (SD) rats and a favorable glucose-lowering effect in diabetic rats. 相似文献
504.
Fagus grandifolia , were investigated throughout its geographical range, using allozyme polymorphisms. A total of 1,131 trees from 21 populations
were examined for 32 alleles of 10 polymorphic and two monomorphic loci in eight enzyme systems. The mean expected heterozygosity
was 0.186, which indicates a relatively high genetic diversity within the populations. The levels of population differentiation
were high, as revealed by genetic parameters, i.e., G
ST
=0.168 and F
ST
=0.167. The results of principal component analysis on allele frequencies clearly revealed unique regional patterns of differentiation
in genetic components among populations “with” and “without” vegetative regeneration by root suckers. The American beech populations
consist of two genetically distinct clusters, one from the Gulf-coastal plain, eastern coastal plain, Piedmont Plateau and
Ozark Plateau; and the other from the remaining northern glaciated territories. Populations from the Blue Ridge and Great
Smoky Mountains turned out to belong to the latter cluster, which is also characterized by extensive regeneration via root
suckers. The consequences of regional differentiation in genetic components are discussed in relation to the postglacial spread
from refugia to the current geographic distributions and the mode of reproduction.
Received 8 August 2000/ Accepted in revised form 29 May 2001 相似文献
505.
Hiroki Nakata Tomohiko Wakayama Yoshimi Takai Shoichi Iseki 《The journal of histochemistry and cytochemistry》2015,63(2):99-113
The aim of this study was to establish a quantitative standard for the cellular composition in seminiferous tubules at each stage of spermatogenesis in the mouse testis, and thereby evaluate abnormalities in the infertile mouse testis. We applied a combination of lectin histochemistry for acrosomes and immunohistochemistry for various specific cell markers, both of which were visualized with fluorescence, on paraffin sections of the testis. We first examined seminiferous tubules from normal mice and counted the number of each cell type at each stage of spermatogenesis. We then examined seminiferous tubules from genetically modified mice deficient (-/-) for one of the cell adhesion molecules, nectin-2 or nectin-3, and compared the number of each cell type at each stage of spermatogenesis with the corresponding value in normal mice. In both nectin-2-/- and nectin-3-/- mice, which are infertile despite the apparently normal morphology of the seminiferous epithelia, we measured a progressive loss in the later-step spermatids, with significantly lower numbers of step 11–16 spermatids in nectin-3-/- mice and step 15–16 spermatids in nectin-2-/- mice as compared with that in normal control mice. The present study demonstrated that a quantitative analysis of cellular compositions at different stages in seminiferous tubules was useful for evaluating abnormalities in spermatogenesis. 相似文献
506.
507.
Shoichi Kuroda Yohei Kobashi Takahiro Oi Kenichi Kawabe Fumiyasu Shiozawa Lisa Okumura-Kitajima Mami Sugisaki-Kitano Fusayo Io Koji Yamamoto Hiroyuki Kakinuma 《Bioorganic & medicinal chemistry》2019,27(2):394-409
A new series of C-phenyl d-glucitol derivatives was designed and synthesized, and their SGLT1 inhibitory potency and absorbability were evaluated. We also investigated whether kidney drug retention could be avoided by creating molecules with different excretion pathways. To achieve a class of molecules with low absorption and that were excreted in bile, optimized synthesis was performed to bring the ClogP value and the topological polar surface area to within the appropriate ranges. Compounds 34d and 34j were poorly absorbed, but the absorbed compounds were mainly excreted in bile. Thus, smaller amounts of persistent residue in the kidneys were observed. Since 34d exerted a glucose-lowering effect at a dose of 0.3?mg/kg (p.o.) in SD rats, this compound (SGL5213) could be a clinical candidate for the treatment of type 2 diabetes. 相似文献
508.
Yukiko Nakamura Makoto Kondo Yoshihisa Koyama Shoichi Shimada 《Biochemical and biophysical research communications》2019,508(2):590-596
The serotonin (5-hydroxytryptamine) type 3 (5-HT3) receptors are transmembrane ligand-gated ion channels. Although several 5-HT3 receptor agonists have been used as preclinical tools, SR 57227A is the most commonly used 5-HT3 receptor agonist with the ability to cross the blood brain barrier. However, the precise pharmacological profile of SR 57227A remains unclear. Therefore, we examined the pharmacological profile of SR 57227A at the 5-HT3A and 5-HT3AB receptors. We microinjected Xenopus laevis oocytes with human 5-HT3A complementary RNA (cRNA) or a combination of human 5-HT3A and human 5-HT3AB cRNA and performed two electrode voltage clamp recordings of 5-HT3A and 5-HT3AB receptor current in the presence of SR 57227A. Results showed that SR 57227A acts as partial agonist/partial antagonist at the 5-HT3 receptor. Interestingly, SR 57227A specifically reduced subsequent current amplitudes induced by 5-HT or SR 57227A. Based on its 5-HT3 receptor partial agonist/partial antagonist properties, we predict that SR 57227A functions as a serotonin stabilizer. 相似文献
509.
510.
DoKyung Lee Eun Jin Kim Paul E. Kilgore Soon Ae Kim Hideyuki Takahashi Makoto Ohnishi Dang Duc Anh Bai Qing Dong Jung Soo Kim Jun Tomono Shigehiko Miyamoto Tsugunori Notomi Dong Wook Kim Mitsuko Seki 《PloS one》2015,10(4)
BackgroundNeisseria meningitidis (Nm) is a leading causative agent of bacterial meningitis in humans. Traditionally, meningococcal meningitis has been diagnosed by bacterial culture. However, isolation of bacteria from patients’ cerebrospinal fluid (CSF) is time consuming and sometimes yields negative results. Recently, polymerase chain reaction (PCR)-based diagnostic methods of detecting Nm have been considered the gold standard because of their superior sensitivity and specificity compared with culture. In this study, we developed a loop-mediated isothermal amplification (LAMP) method and evaluated its ability to detect Nm in cerebrospinal fluid (CSF).Conclusions/SignificanceCompared to PCR, LAMP detected Nm with higher analytical and clinical sensitivity. This sensitive and specific LAMP method offers significant advantages for screening patients on a population basis and for diagnosis in clinical settings. 相似文献