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Kanno  Yosuke  Shu  En  Niwa  Hirofumi  Seishima  Mariko  Ozaki  Kei-ichi 《Molecular biology reports》2021,48(4):3431-3437
Molecular Biology Reports - Systemic sclerosis (SSc) is characterized by peripheral circulatory disturbance and fibrosis in skin and visceral organs. We recently demonstrated that...  相似文献   
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We aimed to investigate novel emerging severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) lineages in Japan that harbor variants in the spike protein receptor-binding domain (RBD). The total nucleic acid contents of samples from 159 patients with coronavirus disease 2019 (COVID-19) were subjected to whole genome sequencing. The SARS-CoV-2 genome sequences from these patients were examined for variants in spike protein RBD. In January 2021, three family members (one aged in their 40s and two aged under 10 years old) were found to be infected with SARS-CoV-2 harboring W152L/E484K/G769V mutations. These three patients were living in Japan and had no history of traveling abroad. After identifying these cases, we developed a TaqMan assay to screen for the above hallmark mutations and identified an additional 14 patients with the same mutations. The associated virus strain was classified into the GR clade (Global Initiative on Sharing Avian Influenza Data [GISAID]), 20B clade (Nextstrain), and R.1 lineage (Phylogenetic Assignment of Named Global Outbreak [PANGO] Lineages). As of April 22, 2021, R.1 lineage SARS-CoV-2 has been identified in 2,388 SARS-CoV-2 entries in the GISAID database, many of which were from Japan (38.2%; 913/2,388) and the United States (47.1%; 1,125/2,388). Compared with that in the United States, the percentage of SARS-CoV-2 isolates belonging to the R.1 lineage in Japan increased more rapidly over the period from October 24, 2020 to April 18, 2021. R.1 lineage SARS-CoV-2 has potential escape mutations in the spike protein RBD (E484K) and N-terminal domain (W152L); therefore, it will be necessary to continue to monitor the R.1 lineage as it spreads around the world.  相似文献   
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Abstract

Lipophilic phosphodiester L-alaninates of acyclic unsaturated nucleoside analogues 1d, 1e, 2d, 2e, 3d, 3e, 4d and 5d were prepared and their antiretroviral activity was examined in ATH8 cell culture infected with HIV-1. A possible mechanism of action of these analogues is discussed.  相似文献   
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Recombinant glycoprotein Ibα latex beads (rGPIbα-LB) are a potential solution to overcoming platelet transfusion problems with artificial platelets. To understand the transport process of artificial platelets and to estimate the particle motion when adhering to the wall surface, we evaluated the lateral motion of rGPIbα-LB in terms of drift and random motion, because the lateral motion is an important factor for transport and adhesion. We observed the lateral motion of rGPIbα-LB flowing with red blood cells toward the immobilized von Willebrand factor (vWf) surface in a model arteriole at wall shear rates of 200–1000 s?1 and 0–40% Hct. At 40% Hct, wall shear rate dependence was observed for the drift motion, i.e. the lateral velocity of rGPIbα-LB toward the wall. In the near-wall region, the drift motion of contacting particles differed substantially from that of non-contacting particles. Additionally, the trajectories of contacting particles on the vWf surface had specific motion that was not observed on the BSA surface. These results suggest that the adhesion force between rGPIbα and vWf is highly associated with the motion of particles near the wall. These features are desirable for artificial platelets, particularly for the adhesion process.  相似文献   
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Two novel glycosides, 4,5-dimethoxy-3-hydroxyphenol 1-O-β-(6′-O-galloyl)-glucopyranoside (1) and (+)-2α-O-galloyl lyoniresinol 3α-O-β-d-xylopyranoside (2), as well as a novel ellagitannin named epiquisqualin B (3), were isolated from sapwood of Quercus mongolica var. crispula along with 19 known phenolic compounds. The structures of the novel compounds were elucidated on the basis of chemical and spectroscopic investigation. Compound 2 is the first example of a lignan galloyl ester, and 3 is the oxidation product of vescalagin, which is the major ellagitannin of this plant.  相似文献   
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Flavonoids have been reported to inhibit tumor growth by causing cell cycle arrest. However, little is known about the direct targets of flavonoids in tumor growth inhibition. In the present study, we developed a novel method using magnetic FG beads to purify flavonoid-binding proteins, and identified ribosomal protein S9 (RPS9) as a binding partner of the flavonoid apigenin. Similar to treatment with apigenin, knockdown of RPS9 inhibited the growth of human colon cancer cells at the G2/M phase by downregulating cyclin-dependent kinase 1 (CDK1) expression at the promoter level. Furthermore, knockdown of RPS9 suppressed G2/M arrest caused by apigenin. These results suggest that apigenin induces G2/M arrest at least partially by directly binding and inhibiting RPS9 which enhances CDK1 expression. We therefore raise the possibility that identification of the direct targets of flavonoids may contribute to the discovery of novel molecular mechanisms governing tumor growth.  相似文献   
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Prolactin-releasing peptide2 (PrRP2) was administered intraperitoneally to male intertidal blenny Rhabdoblennius nitidus, a species with male uniparental care of eggs, to investigate the effect on their feeding activity. A significant inhibitory effect on appetite was observed in the breeding season, but not in the nonbreeding season. These results suggest that PrRP2 and PrRP2 receptors are more active during the breeding season. The presence of a mechanism to inhibit feeding activity while parents take care of their offspring may be important for the success of parental care.  相似文献   
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