Hepatocyte growth factor prevents intimal hyperplasia in rabbit carotid expanded polytetrafluoroethylene grafting

AbstractPurpose: The major cause of vascular prosthesis failure is anastomotic intimal hyperplasia caused by the proliferation and migration of smooth muscle cells. Hepatocyte growth factor (HGF) is an endothelium-specific growth factor that exerts a mitogenic action on endothelial cells. This study was designed to examine the effect of HGF on the suppression of intimal hyperplasia after small-caliber expanded polytetrafluoroethylene (ePTFE) grafting. Methods: An ePTFE graft, 2 mm in diameter and 30 mm in length, was implanted in the left common carotid arteries of Japanese white rabbits, after which the animals were fed with a 1.0% cholesterol diet. HGF was infused intravenously immediately and then every day for 7 days at doses of 0.3 mg/body (the 0.3-mg HGF group; n = 20) or 1.0 mg/body (the 1.0-mg HGF group; n = 17). A control group (n = 20) underwent infusion with saline solution. The rabbits were killed on postoperative days (PODs) 1, 2, 3, 5, 7, and 28. Results: The patency rates on POD 28 were 33%, 55%, and 100% in the control, the 0.3-mg HGF, and the 1.0-mg HGF groups, respectively, with a significant difference between the control and the 1.0-mg HGF group (P <.05). Endothelial-like cells were seen on the intraluminal surface of the graft only near the anastomotic site on POD 5 in the 1.0-mg HGF group. Intimal thickness at the distal anastomosis was 284 ± 140 μm, 106 ± 18 μm, and 67 ± 10 μm in the control, the 0.3-mg HGF, and the 1.0-mg HGF groups, respectively, with a significant difference between the control and both HGF groups (P <.05). The number of anti-embryonic smooth muscle antibody positive cells at the distal anastomosis was 28.6 ± 0.8, 3.8 ± 2.8, and 3.9 ± 0.9 in the control, the 0.3-mg HGF, and the 1.0-mg HGF groups, respectively, with a significant difference between the control and both HGF groups (P <.01). Conclusion: HGF might suppress intimal thickness at the anastomotic site and improve the patency rate via rapid reendothelialization by POD 28 in a rabbit carotid ePTFE grafting model. (J Vasc Surg 2002;35:786-91.

Geolocation-centric Information Platform for Resilient Spatio-temporal Content Management

In IoT era, the growth of data variety is driven by cross-domain data fusion. In this paper, we advocate that “local production for local consumption (LPLC) paradigm” can be an innovative approach in cross-domain data fusion, and propose a new framework, geolocation-centric information platform (GCIP) that can produce and deliver diverse spatio-temporal content (STC). In the GCIP, (1) infrastructure-based geographic hierarchy edge network and (2) adhoc-based STC retention system are interplayed to provide both of geolocation-awareness and resiliency. Then, we discussed the concepts and the technical challenges of the GCIP. Finally, we implemented a proof-of-concepts of GCIP and demonstrated its efficacy through practical experiments on campus IPv6 network and simulation experiments

Electronic structure and correlation in β−Ti3O5 and λ−Ti3O5 studied by hard x-ray photoelectron spectroscopy

We have conducted hard x-ray photoelectron spectroscopy investigations of the electronic structure changes and electron correlation phenomena which take place upon the photoinduced reversible phase transition between β- and λ−Ti3O. From valence band spectra of β- and λ−Ti3O5, we have identified the bipolaron caused by the σ-type bonding of dxy orbitals in β−Ti3O5 and the π stacking between the dxy orbitals between different Ti sites in λ−Ti3O5, previously predicted by ab initio calculations. This indicates that the single electron band picture is valid for the description of photoinduced phase transitions. On the other hand, the Ti 2p and Ti 1s core level spectra exhibit nonlocal screening satellite features, which are typical spectroscopic signs of strong electron correlation in the coherent Tit2g states. The most striking result we obtain is that correlation in the valence band also manifests to reduce the plasmon energy, which results in an enhancement of the valence electron mass by a factor of 2.7

Dielectric collapse at the LaAlO₃/SrTiO₃ (001) heterointerface under applied electric field

Abstract The fascinating interfacial transport properties at the LaAlO3/SrTiO3 heterointerface have led to intense investigations of this oxide system. Exploiting the large dielectric constant of SrTiO3 at low temperatures, tunability in the interfacial conductivity over a wide range has been demonstrated using a back-gate device geometry. In order to understand the effect of back-gating, it is crucial to assess the interface band structure and its evolution with external bias. In this study, we report measurements of the gate-bias dependent interface band alignment, especially the confining potential profile, at the conducting LaAlO3/SrTiO3 (001) heterointerface using soft and hard x-ray photoemission spectroscopy in conjunction with detailed model simulations. Depth-profiling analysis incorporating the electric field dependent dielectric constant in SrTiO3 reveals that a significant potential drop on the SrTiO3 side of the interface occurs within ~2 nm of the interface under negative gate-bias. These results demonstrate gate control of the collapse of the dielectric permittivity at the interface, and explain the dramatic loss of electron mobility with back-gate depletion

大腸3D-CT検査(CT-colonography)における腸管外病変の検出

大腸疾患患者を対象に大腸3D-CT検査(CT-colonography)を施行し,腸管外病変の検出率,検出された腸管外病変の臨床的重要性の分類および大腸疾患の有無と腸管外病変の関係の3項目について検討した.その結果,対象者112例のうち84.8%の症例に少なくとも1つ以上の腸管外病変を認めた.また,対象例のうち33例(29.5%)にカテゴリーE4(臨床上重要な所見を有する)群に分類される腸管外病変を認めた.そして,カテゴリーE4群のうち大腸内視鏡検査で24例(72.7%)が大腸癌と,4例(12.1%,全例に対する比率:3.6%)が所見なしと診断された.これらのことから,大腸疾患およびその疑いを有する症例にCT-colonographyを施行することは,大腸疾患を有する症例はもとより内視鏡検査で所見なしと診断された症例においても,重大な腸管外病変の早期発見に有用である