55 research outputs found
A supersolutions perspective on hypercontractivity
The purpose of this article is to expose an algebraic closure property of
supersolutions to certain diffusion equations. This closure property quickly
gives rise to a monotone quantity which generates a hypercontractivity
inequality. Our abstract argument applies to a general Markov semigroup whose
generator is a diffusion and satisfies a curvature condition.Comment: 7 page
Ganglion cyst arising from the infrapatellar fat pad in a child
A ganglion cyst is a cystic lesion containing myxoid matrix and lined by a pseudomembrane. A ganglion cyst arising from the infrapatellar fat pad is very rare, with only a few reports appearing in the literature, and the present case is the first report of this lesion in a child. A 10-year-old boy presented with right knee pain that showed no improvement despite resting from sports activity for 1 month. Magnetic resonance imaging revealed a multilobular mass between the infrapatellar fat pad and anterior cruciate ligament. Arthroscopic excision of the mass was performed. The mass was noted to arise from the infrapatellar fat pad and was filled with myxoid matrix. The histological diagnosis was a ganglion cyst. In active pediatric patients with pain or limited range of motion in the knee, physicians should consider the possibility of a ganglion cyst from the infrapatellar fat pad, despite its rarity
Self-assembly of Ni-NTA-modified β-Annulus Peptides into Artificial Viral Capsids and Encapsulation of His-tagged Proteins
β-Annulus peptide bearing Cys at the N-terminal from tomato bushy stunt virus was synthesised using a standard Fmoc-protected solid-phase method, and the petide was modified with Ni-NTA at the N-terminal. The Ni-NTA-modified β-annulus peptide self-assembled into virus-like nanocapsules of approximately 40 nm in diameter. The critical aggregation concentration of these nanocapsules in 10 mM Tris-HCl buffer (pH 7.3) at 25°C was 0.053 μM, which is 470 times lower than that of unmodified β-annulus peptides. Moreover, size exclusion chromatography of the peptide assembly indicated encapsulation of His-tagged green fluorescent protein in the Ni-NTA-modified artificial viral capsid
ホウゲン シュウトク ニ カンスル イチ コウサツ ヒ カンサイケン シュッシン ダイガクセイ ノ ケイハンシキ アクセント シュウトク ヲ メグル チョウサ ケッカ ヲ モト ニ
時空と認知の言語学(11
Identification of a novel arthritis-associated osteoclast precursor macrophage regulated by FoxM1
Osteoclasts have a unique bone-destroying capacity, playing key roles in steady-state bone remodeling and arthritic bone erosion. Whether the osteoclasts in these different tissue settings arise from the same precursor states of monocytoid cells is presently unknown. Here, we show that osteoclasts in pannus originate exclusively from circulating bone marrow-derived cells and not from locally resident macrophages. We identify murine CX3CR1hiLy6CintF4/80+I-A+/I-E+ macrophages (termed here arthritis-associated osteoclastogenic macrophages (AtoMs)) as the osteoclast precursor-containing population in the inflamed synovium, comprising a subset distinct from conventional osteoclast precursors in homeostatic bone remodeling. Tamoxifen-inducible Foxm1 deletion suppressed the capacity of AtoMs to differentiate into osteoclasts in vitro and in vivo. Furthermore, synovial samples from human patients with rheumatoid arthritis contained CX3CR1+HLA-DRhiCD11c+CD80−CD86+ cells that corresponded to mouse AtoMs, and human osteoclastogenesis was inhibited by the FoxM1 inhibitor thiostrepton, constituting a potential target for rheumatoid arthritis treatment.Hasegawa T., Kikuta J., Sudo T., et al. Identification of a novel arthritis-associated osteoclast precursor macrophage regulated by FoxM1. Nature Immunology 20, 1631 (2019); https://doi.org/10.1038/s41590-019-0526-7
SARS-CoV-2 disrupts respiratory vascular barriers by suppressing Claudin-5 expression
臓器チップ技術を用いて新型コロナウイルスが血管へ侵入するメカニズムを解明 --Claudin-5発現抑制による呼吸器の血管内皮バリア破壊--. 京都大学プレスリリース. 2022-09-22.A study using an organ-on-a-chip reveals a mechanism of SARS-CoV-2 invasion into blood vessels --Disruption of vascular endothelial barrier in respiratory organs by decreasing Claudin-5 expression--. 京都大学プレスリリース. 2022-09-27.In the initial process of coronavirus disease 2019 (COVID-19), severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infects respiratory epithelial cells and then transfers to other organs the blood vessels. It is believed that SARS-CoV-2 can pass the vascular wall by altering the endothelial barrier using an unknown mechanism. In this study, we investigated the effect of SARS-CoV-2 on the endothelial barrier using an airway-on-a-chip that mimics respiratory organs and found that SARS-CoV-2 produced from infected epithelial cells disrupts the barrier by decreasing Claudin-5 (CLDN5), a tight junction protein, and disrupting vascular endothelial cadherin–mediated adherens junctions. Consistently, the gene and protein expression levels of CLDN5 in the lungs of a patient with COVID-19 were decreased. CLDN5 overexpression or Fluvastatin treatment rescued the SARS-CoV-2–induced respiratory endothelial barrier disruption. We concluded that the down-regulation of CLDN5 expression is a pivotal mechanism for SARS-CoV-2–induced endothelial barrier disruption in respiratory organs and that inducing CLDN5 expression is a therapeutic strategy against COVID-19
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