533 research outputs found

    Regulatory effects of blood constituents on the function and metabolism of the cat brain in perfusion ezperiments. Brain perfusion with artificial blood containing low molecular dextran and amino acids

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    As a link in a series of studies on the effects of blood constituents on the brain function by means of brain perfusion, we used four kinds of artificial blood; namely, the blood containing a low molecular dextran, one containing glutamic acid, one containing essential amino acid group and the one containing both essential amino acid group and glutamic acid. During the perfusion experiments we observed the effects of blood constituents on the function and metabolism of the perfused brain and obtained the following results. 1. When a low molecular dextran is used as the colloid osmotic pressure agent instead of hydrodextran, the amount of the blood flow in the brain is maintained roughly at a certain fixed level throughout the experiment, showing no gradual decreasing tendency. 2. When using the artificial blood supplemented with glutamic acid, EEG of the perfused brain shows an increase in the appearance rate of &#946;32 and &#946;33 bands, approaching closely to the pattern of EEG of unrestrained controls at arousal state. 3. In the case of the blood added with essential amino acids similar to the case using the blood with glutamic acid, EEG approaches towards the alert pattern of the controls. 4. When the perfusion is done with the artificial blood lacking in amino acids, about one hour after the start of the perfusion the amount of glutamic acid and its related compounds in the brain can no longer be maintained at normal level and the decrease, being so marked, brings about a marked decrease also in total amino acid content. 5. When the perfusion blood contains glutamic acid, essential amino acid group or both, the concentrations of amino acids of the brain glutamic acid group and the total amino acid can be maintained approximately at normal level for the duration of over one hour.</p

    Electrical transport properties of small diameter single-walled carbon nanotubes aligned on ST-cut quartz substrates

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    A method is introduced to isolate and measure the electrical transport properties of individual single-walled carbon nanotubes (SWNTs) aligned on an ST-cut quartz, from room temperature down to 2 K. The diameter and chirality of the measured SWNTs are accurately defined from Raman spectroscopy and atomic force microscopy (AFM). A significant up-shift in the G-band of the resonance Raman spectra of the SWNTs is observed, which increases with increasing SWNTs diameter, and indicates a strong interaction with the quartz substrate. A semiconducting SWNT, with diameter 0.84 nm, shows Tomonaga-Luttinger liquid and Coulomb blockade behaviors at low temperatures. Another semiconducting SWNT, with a thinner diameter of 0.68 nm, exhibits a transition from the semiconducting state to an insulating state at low temperatures. These results elucidate some of the electrical properties of SWNTs in this unique configuration and help pave the way towards prospective device applications

    冠動脈高度石灰化病変に対するスコアリングバルーンラクロスNon-Slip Elementを用いた冠動脈形成術-光干渉断層法による有用性の評価

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    Percutaneous coronary intervention (PCI) for heavily calcified lesions is challenging because these lesions are resistant to balloon dilatation and stenting. Lacrosse non-slip element (NSE) may have the potential to dilate heavily calcified lesions. We aimed to investigate predictors of successful lesion modification using Lacrosse NSE angioplasty via optical coherence tomography (OCT)-guided PCI. We investigated 32 patients with severe target lesion calcification treated with OCT-guided PCI. Successful lesion modification was defined as the complete fracture of calcification after Lacrosse NSE angioplasty. Before PCI, 172 segments with calcification were identified. After pre-dilatation using Lacrosse NSE, successful lesion modification was achieved in 117 segments (68.0%). Calcification was significantly thinner in successfully disrupted segments than in non-disrupted segments (p < 0.001). Calcification angle tended to be larger in disrupted than in non-disrupted segments (p = 0.08). Convex types were less frequently observed in disrupted than in non-disrupted segments (p < 0.001). At minimal lumen area sites, 26 segments (81.3%) were successfully modified. Similar to the overall results, the disrupted group had significantly thinner calcification than the non-disrupted group (p < 0.001). The angle of the calcified plaque was similar between the 2 groups (p = 0.39). Convex-type calcifications were less frequently observed in the disrupted group than in the non-disrupted group (p = 0.05). Receiver-operating characteristic curve analysis showed that calcification thickness < 565 μm was the best predictor of completely disrupted calcification. The thickness and shape of calcifications were predictors of successful lesion modification after Lacrosse NSE angioplasty.博士(医学)・乙第1426号・平成31年3月15日© Japanese Association of Cardiovascular Intervention and Therapeutics 2018This is a post-peer-review, pre-copyedit version of an article published in Cardiovascular intervention and therapeutics. The final authenticated version is available online at: http://dx.doi.org/10.1007/s12928-018-0553-6

    737–1 Heart Fatty Acid-binding Protein and Myoglobin can Accurately Detect Successful Reperfusion as Early as 15 Minutes After Reperfuslon

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    Human heart fatty acid-binding protein (FABP) is an abundant low molecular weight protein in cytoplasm of myocardial cell similar to myoglobin (Mb). To evaluate whether FABP can also detect successful reperfusion very early like Mb, we examined serum FABP and Mb levels in 45 patients (pts) undergoing PTCR or PTCA within 6 hours after the onset of acute myocardial infarction. Coronary angiography was performed every 5minutes (min) during reperfusion therapy to determine the exact time of reperfusion. In 30 pts with reperfusion (reperfused group: TIMI grade 3 [23 pts] and grade 2 [7 pts]), serum samples were taken just before and at 15, 30 and 60min after initial angiographic confirmation of reperfusion. In 15 pts without reperfusion (nonreperfused group), serum samples were taken just before and at 15, 30 and 60min after the initiation of therapy. FABP was measured by competitive enzyme immunoassay and Mb by latex agglutination turbidimetry. The FABP ratio (FABP after/FABP before) and Mb ratio (Mb after/Mb before) were calculated. FABP and Mb levels increased rapidly, peaked within 60min after reperfusion. The FABP and Mb ratios in the reperfused group significantly (p&lt;0.01) exceeded those in the nonreperfused group at 15, 30 and 60 min. The sensitivity (Sen) and specificity (Spe) of these markers for reperfusion were as follows:Criteria15 min30 min60 minSenSpeSenSpeSenSpeFABP ratio&gt;1.6*93%100%97%100%100%100%Mb ratio&gt;2.4**90%100%93%100%100%100%*mean +2SD at 60 min in the nonreperfused group**published criteriaConclusionFABP, like Mb could accurately detect successful reperfusion as early as 15min after reperfusion and could provide a high level of accuracy within 60min after reperfusion
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