階段昇降試験中に認められる酸素飽和度低下 : 肺切除を予定している患者の術後合併症の予測指標

Objective: It is widely accepted that exercise tolerance tests are applicable in perioperative risk assessment for patients who undergo pulmonary resection; however, the relevance of desaturation during the test is unclear. The purpose of this study was to investigate whether the occurrence of desaturation during a stair-climbing test can be a predictor of postoperative complications among patients who will undergo pulmonary resection and are considered "normal risk" according to published guidelines. Methods: Desaturation was defined as a depression of more than 4% points on a pulse oximeter during stair climbing. Among 186 consecutive patients who underwent pulmonary resection, 162 patients who could climb to the 6th floor were selected for the study (excluding 21 patients who could not stair-climb and 3 patients who could not climb from the first floor to the sixth floor). The relationship of desaturation with postoperative complication was investigated using parameters of cardio-pulmonary status associated with additional foci of oxygen supply duration, intensive care unit stay duration, and hospital stay duration. Results: The occurrence ratio of postoperative complications > grade 3 (Clavien-Dindo classification) was 0.75% (1/133) among patients without desaturation and 17.2% (5/29) in patients with desaturation (difference: p = 0.0002). In addition, DS was an indicator of prolonged oxygen supply duration, intensive care unit stay duration, and hospital stay duration. Conclusion: The occurrence of desaturation during a stair-climbing test for patients who will undergo pulmonary resection can be a predictor of postoperative complications among patients who are classified as having normal risk.博士（医学）・乙第1457号・令和2年6月30日© The Japanese Association for Thoracic Surgery 2019© 2019 Springer Nature Switzerland AG. Part of Springer Nature.This is a post-peer-review, pre-copyedit version of an article published in General thoracic and cardiovascular surgery. The final authenticated version is available online at: http://doi.org/10.1007/s11748-019-01153-z.本文の登録不可。本文は以下のURLを参照 "https://doi.org/10.1007/s11748-019-01153-z"（※全文閲覧は学内限定

Confocal microphotoluminescence of InGaN-based light-emitting diodes

Spatially resolved photoluminescence (PL) of InGaN/GaN/AlGaN-based quantum-well-structured light-emitting diodes (LEDs) with a yellow-green light (530 nm) and an amber light (600 nm) was measured by using confocal microscopy. Submicron-scale spatial inhomogeneities of both PL intensities and spectra were found in confocal micro-PL images. We also found clear correlations between PL intensities and peak wavelength for both LEDs. Such correlations for yellow-green and amber LEDs were different from the reported correlations for blue or green LEDs. This discrepancy should be due to different diffusion, localization, and recombination dynamics of electron-hole pairs generated in InGaN active layers, and should be a very important property for influencing the optical properties of LEDs. In order to explain the results, we proposed a possible carrier dynamics model based on the carrier localization and partial reduction of the quantum confinement Stark effect depending on an indium composition in InGaN active layers. By using this model, we also considered the origin of the reduction of the emission efficiencies with a longer emission wavelength of InGaN LEDs with high indium composition

Closed-cycle cold helium magic-angle spinning for sensitivity-enhanced multi-dimensional solid-state NMR

AbstractMagic-angle spinning (MAS) NMR is a powerful tool for studying molecular structure and dynamics, but suffers from its low sensitivity. Here, we developed a novel helium-cooling MAS NMR probe system adopting a closed-loop gas recirculation mechanism. In addition to the sensitivity gain due to low temperature, the present system has enabled highly stable MAS (vR=4–12kHz) at cryogenic temperatures (T=35–120K) for over a week without consuming helium at a cost for electricity of 16kW/h. High-resolution 1D and 2D data were recorded for a crystalline tri-peptide sample at T=40K and B0=16.4T, where an order of magnitude of sensitivity gain was demonstrated versus room temperature measurement. The low-cost and long-term stable MAS strongly promotes broader application of the brute-force sensitivity-enhanced multi-dimensional MAS NMR, as well as dynamic nuclear polarization (DNP)-enhanced NMR in a temperature range lower than 100K

Microscale flow dynamics of red blood cells in microchannels: an experimental and numerical analysis

Approximately, the half volume of the blood is composed of red blood cells (RBCs) which is believed to strongly influence its flow properties. Blood flow in microvessels depends strongly on the motion, deformation and interaction of RBCs. Several experimental studies on both individual and concentrated RBCs have already been performed in the past (Goldsmith 1971, Goldsmith and Marlow 1979, Chien et al. 1984, Goldsmith and Turitto 1986). However, all studies used conventional microscopes and also ghost cells to obtain visible trace RBCs through the microchannel. Recently, considerable progress in the development of confocal microscopy and consequent advantages of this microscope over the conventional microscopes have led to a new technique known as confocal micro-PIV (Tanaami et al. 2002, Park et al. 2004, Lima et al. 2006, 2007a). This technique combines the conventional PIV system with a spinning disk confocal microscope (SDCM). Due to its outstanding spatial filtering technique together with the multiple point light illumination system, this technique has the ability to obtain in-focus images with optical thickness less than 1 mm. In a numerical context, blood flow in large arteries is usually modeled as a continuum however this assumption is not valid in small vessels such as arterioles and capillaries. In this way, we are developing an integrative multi-scale model to simulate the blood flow at mesoscopic level. This computational approach may provide important information on the rheology of blood in small vasculatures where non-Newtonian property of blood is not negligible. The main purpose of this paper is to measure flow behavior of individual RBCs at different haematocrits (Hct) through a 75mm circular polydimethysiloxane (PDMS) microchannel by means of confocal micro-PTV system. Moreover we introduce an integrative multi-scale model to simulate the blood flow behavior through microvessels in order to obtain more detailed insights about the blood rhelogical properties at cellular level.This study was supported in part by the following grants: International Doctoral Program in Engineering from the Ministry of Education, Culture, Sports, Science and Technology of Japan (MEXT), “Revolutionary Simulation Software (RSS21)” next-generation IT program of MEXT; Grants-in-Aid for Scientific Research from MEXT and JSPS Scientific Research in Priority Areas (768) “Biomechanics at Micro- and Nanoscale Levels,” Scientific Research (A) No.16200031 “Mechanism of the formation, destruction, and movement of thrombi responsible for ischemia of vital organs”, Grant-in-Aid for Young Scientists (A) 19680024

Light and Electron Microscopic Studies of Microcalcifications Appearing in Monomorphic Adenomas

Microcalcifications appearing in two cases of monomorphic adenomas were studied histopathologically, electron microscopically, and electron-microanalytically. One case was basal cell adenoma that occurred in a 56-year-old man and the other was canalicular adenoma in a 71-year-old woman. The calcified granules were observed both in the lumina formed by the tumor cells and in the stromal tissues. The surroundings of the granules were stained by alcian blue and showed a sulfur peak by EPMA. These facts suggest that the surroundings contain sulfated glycosaminoglycans and that sulfur has a significant role in the mechanisms of pathological calcification as well as physiological calcification