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61.
Camila I. Irion Monique Williams Jose Condor Capcha Trevor Eisenberg Guerline Lambert Lauro M. Takeuchi Grace Seo Keyvan Yousefi Rosemeire Kanashiro-Takeuchi Keith A. Webster Karen C. Young Joshua M. Hare Lina A. Shehadeh 《International journal of molecular sciences》2022,23(12)
Alport syndrome (AS) is a hereditary renal disorder with no etiological therapy. In the preclinical Col4a3-/- model of AS, disease progression and severity vary depending on mouse strain. The sodium-glucose cotransporter 2 (SGLT2) is emerging as an attractive therapeutic target in cardiac/renal pathologies, but its application to AS remains untested. This study investigates cardiorespiratory function and SGLT2 renal expression in Col4a3-/- mice from three different genetic backgrounds, 129x1/SvJ, C57Bl/6 and Balb/C. male Col4a3-/- 129x1/SvJ mice displayed alterations consistent with heart failure with preserved ejection fraction (HFpEF). Female, but not male, C57Bl/6 and Balb/C Col4a3-/- mice exhibited mild changes in systolic and diastolic function of the heart by echocardiography. Male C57Bl/6 Col4a3-/- mice presented systolic dysfunction by invasive hemodynamic analysis. All strains except Balb/C males demonstrated alterations in respiratory function. SGLT2 expression was significantly increased in AS compared to WT mice from all strains. However, cardiorespiratory abnormalities and SGLT2 over-expression were significantly less in AS Balb/C mice compared to the other two strains. Systolic blood pressure was significantly elevated only in mutant 129x1/SvJ mice. The results provide further evidence for strain-dependent cardiorespiratory and hypertensive phenotype variations in mouse AS models, corroborated by renal SGLT2 expression, and support ongoing initiatives to develop SGLT2 inhibitors for the treatment of AS. 相似文献
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Lixin Xiao Koichi Kitazawa Kazuhiko Saigo 《Fullerenes, Nanotubes and Carbon Nanostructures》2013,21(6):531-543
Abstract A series of [60]fullerene pearl-necklace polyamides, consisting of equatorial-[60]fullerenobisacetic acid and various chromophoric aromatic diamines, were synthesized by a phosphorylation route using large amounts of triphenyl phosphite and pyridine as condensing reagents with stepwise addition of the condensing reagents. In the present polymers, [60]fullerene pearls and diamine linkers were attached to one another by cyclopropane connectors. The polyamides had weight-average molecular weights (Mw)of 4.5-5.0×104 g/mol and inherent viscosities (n inh) of 0.3-0.4 dL/g in N, N-dimethylacetamide (DMAc) at 30 °C. They had glass transition temperatures at 30-125 °C and decomposition temperatures at 300-310 °C. The UV-VIS spectra in DMAc exhibited broad absorption with λmax at 310-390 nm tailing to longer wavelengths. 相似文献
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Kenji Hirota Kazuhiko Kitamura Yoshihiko Ukai Keiichi Matsunaga 《Journal of Materials Processing Technology》2014,214(10):2095-2101
In this paper, a new assembling method of spline joints that enables tight fitting in a simple manner by allowing slight plastic deformation at the spline teeth was introduced. Experiments were carried out for the spline joints of medium carbon steel varying the overlap zone between the male and the female spline teeth. Axial joining strength was increased with increase in the overlap length due to the residual compressive stress by forming. The joint by the proposed method also showed higher torsional strength than the conventional joint. Improvement in the torsional strength was explained based on the deformation and hardness distribution around the spline teeth. With respect to the shape of overlap zone, better results were obtained when using the specimen having a uniform overlap length along the axial direction. 相似文献
66.
Takuya Isomura Akimasa Takeuchi Kenta Shimba Kiyoshi Kotani Yasuhiko Jimbo 《Electrical Engineering in Japan》2014,187(4):42-50
Recently, there has been abundant research using multineuron recording, but there are many problems with extracting the features from the obtained spike time series, which are huge in volume and complex. Here we introduce a new method of estimating synaptic connection strengths between neurons by fitting to the Izhikevich model by maximum likelihood estimation. We demonstrate that our method can estimate connection strengths from spike time series given by a simulated neural ensemble and can estimate nonconnectivity between two independent cultured neuronal networks. These results suggest that our method is applicable to network and plasticity analysis of neuronal networks. 相似文献
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Amnach Khawne Boonwat Attachoo Kazuhiko Hamamoto 《IEEJ Transactions on Electrical and Electronic Engineering》2015,10(2):149-156
To prevent unauthorized access to a person's medical images, it is widely acknowledged that the security features of confidentiality, availability and integrity should be in place. This paper proposes the watermarking of ultrasonic echo images together with optimal watermark detection, in which pseudorandom noise is added to the images for integrity. The optimum watermark detection is the integration of the generalized Gaussian distribution (ρ‐GGD) and the Cauchy distribution. The results show that the proposed method gives good detection performance. The proposed method not merely achieves optimum detection using the Rao test but also leads to the highest detection probability with JPEG2000 compression. Compared with other detection methods, our proposed method exhibits better watermark detection performance even when the watermark‐to‐document ratio (WDR) is −50 dB. © 2014 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc. 相似文献
70.
Joao Gari da Silva Fonseca Junior Takashi Oozeki Hideaki Ohtake Takumi Takashima Kazuhiko Ogimoto 《Progress in Photovoltaics: Research and Applications》2015,23(10):1203-1218
The development of methods to forecast photovoltaic (PV) power generation regionally is of utmost importance to support the spread of such power systems in current power grids. The objective of this study is to propose and to evaluate methods to forecast regional PV power 1 day ahead of time and to compare their performances. Four forecast methods were regarded, of which two are new ones proposed in this study. Together, they characterize a set of forecast methods that can be applied in different scenarios regarding availability of data and infrastructure to make the forecasts. The forecast methods were based on the use of support vector regression and weather prediction data. Evaluations were performed for 1 year of hourly forecasts using data of 273 PV systems installed in two adjacent regions in Japan, Kanto, and Chubu. The results show the importance of selecting the proper forecast method regarding the region characteristics. For Chubu, the region with a variety of weather conditions, the forecast methods based on single systems' forecasts and the one based on stratified sampling provided the best results. In this case, the best annual normalized root mean square error (RMSE) and mean absolute error (MAE) were 0.25 and 0.15 kWh/kWhavg, respectively. For Kanto, with homogeneous weather conditions, the four methods performed similarly. In this case, the lowest annual forecast errors were 0.33 kWh/kWhavg for the normalized RMSE and 0.202 kWh/kWhavg for the normalized MAE. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献