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101.
Reina Matsui Takeshi Hagino Nelson Hirokazu Tsuno Hideo Ohtani Fumihiro Azuma Mika Matsuhashi Makoto Saito Maya Kobayashi Reina Saga Hiroko Hidai Hisashi Tsutsumi Hideki Akiyama Sayuri Motomura 《Transfusion and apheresis science》2021,60(3):103123
The measurement of corrected count increment at 1-h post-transfusion (CCI-1 h) of platelet concentrate (PC) transfusion is recommended, but in the revised Japanese Guideline (2017) it was changed to “after 10-min to 1-h”, following the revision of the guidelines from Western countries. Here, we aimed to investigate on the feasibility to apply the CCI measured at 10-min or 30-min post-transfusion as the surrogate of CCI-1 h. Peripheral blood was collected at 10-min, 30-min and 1-h post-transfusion of PC and the effectiveness of the transfusion was analyzed based on the CCI. In the period from December 2017 to February 2020, 8 patients, who received multiple PC transfusion (total 208) at our institution, were analyzed. We performed the univariate analyses to examine the relationship between CCI value and the categorical variables, p-value <0.1 was obtained for gender (p = 2.91 × 10?19), fever after transfusion (p = 0.0163). The qualitative variables, namely measurement time (p = 0.0553), also showed p-value <0.1. Using these factors as covariates in the mixed effect model, we found that the measurement time (p = 0.0007) had a significant effect on the CCI value when looking at fixed effects. Although there is a tendency for decreased CCI values with time progression, the slope of the change in the mixed model was -0.00307, indicating that the CCI difference among the 3 measurements was small. Here we provide evidence that CCI measured at 10-min and 30-min post-transfusion give results comparable to those measured at 1-h post-transfusion, under the Japanese practice of platelet transfusion, which relies on 100 % single-donor apheresis PC, and ABO-identical whenever possible. 相似文献
102.
Rifu Kazuma Sasanuma Hideki Takayama Noriya Nitta Naotaka Ogata Yukiyo Akiyama Iwaki Taniguchi Nobuyuki 《Journal of Medical Ultrasonics》2021,48(2):137-144
Journal of Medical Ultrasonics - We previously reported that acoustic radiation force impulse (ARFI) with concomitant administration of perfluorobutane as an ultrasound contrast agent (UCA)-induced... 相似文献
103.
T. Matsushige Y. Akiyama T. Okazaki K. Shinagawa N. Ichinose K. Awai K. Kurisu 《AJNR. American journal of neuroradiology》2015,36(8):1507
BACKGROUND AND PURPOSE:Inflammation and degeneration of the intracranial saccular aneurysm wall play a major role in aneurysm formation, development and subsequent rupture. The aim of this study was to characterize the walls of unruptured intracranial aneurysms by using a hybrid of opposite-contrast MRA at 3T.MATERIALS AND METHODS:Fourteen consecutive patients with 17 unruptured intracranial aneurysms who initially underwent clipping surgery were prospectively evaluated. All aneurysms were scanned preoperatively by using a hybrid of opposite-contrast MRA in 3T high-resolution MR imaging. We classified intraoperative findings of atherosclerotic plaques in the aneurysms into 3 grades: grade A (major plaques), grade B (minor plaques), and grade C (no plaques). The contrast ratio of the high-intensity area was also measured relative to the background low-intensity area inside the carotid artery.RESULTS:Findings from preoperative plaque imaging of the aneurysm corresponded to the intraoperative findings in 15 of 16 aneurysms (excluding 1 that was impossible to visualize in its entirety due to anatomic reasons). Overall sensitivity and specificity of the hybrid of opposite-contrast MRA were 88.9% and 100%, respectively. During the operation, 4 aneurysms were classified as grade A; 5, as grade B; and 7, as grade C. The means of the contrast ratio for grades A, B, and C were 0.72 ± 0.03, 0.34 ± 0.30, and −0.02 ± 0.09, respectively.CONCLUSIONS:The hybrid of opposite-contrast MRA can detect visible atherosclerotic plaques in the unruptured aneurysm wall, and the contrast ratio in intracranial aneurysms correlated with their presence and extent. A study including a larger series is needed to validate the diagnostic potential of this imaging technique.Intracranial aneurysms are common vascular lesions, often consisting of a saccular dilation of a cerebral artery vessel. The prevalence of intracranial aneurysms in the general population is estimated between 2.5% and 5%.1,2 Aneurysmal rupture occurs with a 1% risk per year, depending on the size, location, and morphometry of the aneurysm, and leads to subarachnoid hemorrhage with associated high morbidity and mortality rates.1,2 Intracranial aneurysms with an estimated high risk of rupture undergo management via a surgical or endovascular approach, depending on the specific risks of treatment.3,4 Therefore, it is important to accurately assess the risk of aneurysmal rupture.The pathogenesis of intracranial aneurysms and their natural history are not well-understood. Histopathologic studies have shown that the infiltration of inflammatory cells and the degeneration of the aneurysm wall with atherosclerosis correlates with the formation, development, and rupture risk of cerebral aneurysms.5–9 However, characterization of the aneurysm wall is limited by imaging data quality and the need to harvest surgical specimens.In this regard, the characteristics of high-field-strength MR imaging, which has a favorable SNR and changes in relaxation time and susceptibility, can depict the intracranial vessel walls and their pathologies, including small vessels with atherosclerosis.10,11The hybrid of opposite-contrast MR angiography (HOP-MRA) used in this study is a modern technique that combines the advantages of 3D TOF MRA and flow-sensitive black-blood (FSBB) MRA.12 The clinical efficacy of this technique was established to improve the visualization of peripheral vessels.13,14 Theoretically, tissue with shorter T1 and T2* introduces high signal in FSBB of HOP-MRA, which demonstrates atherosclerotic plaques, including fat, as high-signal-intensity areas and demonstrates the blood space as low-signal-intensity areas in intracranial aneurysms.12 The strength of this technique is the dual-echo 3D gradient-echo sequence, which enables a shorter imaging time and minimization of misregistration. The present study investigated the utility of HOP-MRA at 3T for the characterization of visible atherosclerotic plaques in intracranial aneurysms by using subtraction between TOF and FSBB imaging. 相似文献
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106.
Eikan Mishima Shinji Fukuda Hisato Shima Akiyoshi Hirayama Yasutoshi Akiyama Yoichi Takeuchi Noriko N. Fukuda Takehiro Suzuki Chitose Suzuki Akinori Yuri Koichi Kikuchi Yoshihisa Tomioka Sadayoshi Ito Tomoyoshi Soga Takaaki Abe 《Journal of the American Society of Nephrology : JASN》2015,26(8):1787-1794
The accumulation of uremic toxins is involved in the progression of CKD. Various uremic toxins are derived from gut microbiota, and an imbalance of gut microbiota or dysbiosis is related to renal failure. However, the pathophysiologic mechanisms underlying the relationship between the gut microbiota and renal failure are still obscure. Using an adenine-induced renal failure mouse model, we evaluated the effects of the ClC-2 chloride channel activator lubiprostone (commonly used for the treatment of constipation) on CKD. Oral administration of lubiprostone (500 µg/kg per day) changed the fecal and intestinal properties in mice with renal failure. Additionally, lubiprostone treatment reduced the elevated BUN and protected against tubulointerstitial damage, renal fibrosis, and inflammation. Gut microbiome analysis of 16S rRNA genes in the renal failure mice showed that lubiprostone treatment altered their microbial composition, especially the recovery of the levels of the Lactobacillaceae family and Prevotella genus, which were significantly reduced in the renal failure mice. Furthermore, capillary electrophoresis–mass spectrometry-based metabolome analysis showed that lubiprostone treatment decreased the plasma level of uremic toxins, such as indoxyl sulfate and hippurate, which are derived from gut microbiota, and a more recently discovered uremic toxin, trans-aconitate. These results suggest that lubiprostone ameliorates the progression of CKD and the accumulation of uremic toxins by improving the gut microbiota and intestinal environment. 相似文献
107.
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109.
Effects of vitamin K(2) (menatetrenone) and alendronate on bone mineral content and bone mechanical property in rats fed a low-magnesium diet. Recent clinical studies have shown that the occurrence of new fractures does not always depend on bone mineral density. Therefore bone quality has become an important issue in osteoporosis research. No animal model for evaluating bone quality has been established. In this study, we found that the treatment of rats with a low-magnesium (Mg) diet reduced their bone strength without decreasing bone mineral content (BMC), so the low Mg diet model is considered to be a good model for examining bone quality. Using this model, we investigated the effects of vitamin K(2) (V.K(2)) and alendronate (ALN). V.K(2) increased maximum load and elastic modulus without influencing BMC. ALN increased maximum load with increasing BMC. By using Fourier transform infrared microscopic analysis, the low-Mg diet treatment increased the mineral/matrix ratio of bones, and V.K(2) suppressed the increase in this ratio. These findings suggest that the mineral/matrix ratio may be a factor involved in bone quality, and that V.K(2) may improve bone quality. 相似文献
110.
Uetsuka Y Hosoda S Kasanuki H Aosaki M Murasaki K Ooki K Inoue M Akiyama E Kitada M 《Heart and vessels》2000,15(3):124-128
The thrombotest (TT) technique has been widely used in Japan for monitoring oral anticoagulant therapy (OAT). The therapeutic
range was originally recommended to be 10%–25%. However, the International Committee for Standardization in Hematology/International
Committee on Thrombosis and Hemostasis (ICSH/ICTH) recommended using the international normalized ratio of prothrombin time
(PT-INR) for monitoring OAT. It is necessary to use a universal standard measure for monitoring OAT in accordance with the
ICSH/ISTH recommendation. We simultaneously measured TT and PT in blood samples from 1 157 patients on long-term warfarin
therapy, and studied the correlation between TT and PT-INR. An excellent linear correlation was obtained between TT-INR and
PT-INR with the regression equation PT-INR = 1.0420 TT-INR − 0.0987 (r = 0.905, P < 0.001). We also examined the correlation between the incidence of thromboembolism in 170 patients receiving warfarin therapy
after prosthetic valve replacement; 50.5% received concomitant antiplatelet therapy. Thromboembolism occurred in 9 of 170
patients during a mean follow-up period of 2.44 years. The average TT values in patients with and without thromboembolism
were 26.4% (PT-INR: 1.53) and 21.1% (1.73), respectively (P < 0.01). The incidence of thromboembolism did not differ significantly between patients on warfarin alone (average TT: 22.2%)
and those on warfarin and antiplatelet agent (average TT: 20.9%). Our results suggest that the incidence of thromboembolism
is low in Japan despite a less intensive regimen having been adopted.
Received: June 22, 2000 / Accepted: October 4, 2000 相似文献