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  1. Article ; Online: Roles of the mechanosensitive ion channel Piezo1 in the renal podocyte injury of experimental hypertensive nephropathy.

    Ogino, Satoyuki / Yoshikawa, Kei / Nagase, Takashi / Mikami, Kaori / Nagase, Miki

    Hypertension research : official journal of the Japanese Society of Hypertension

    2023  Volume 47, Issue 3, Page(s) 747–759

    Abstract: Glomerular podocyte injury plays an essential role in proteinuria pathogenesis, a hallmark of chronic kidney disease, including hypertensive nephropathy. Although podocytes are susceptible to mechanical stimuli, their mechanotransduction pathways remain ... ...

    Abstract Glomerular podocyte injury plays an essential role in proteinuria pathogenesis, a hallmark of chronic kidney disease, including hypertensive nephropathy. Although podocytes are susceptible to mechanical stimuli, their mechanotransduction pathways remain elusive. Piezo proteins, including Piezo1 and 2, are mechanosensing ion channels that mediate various biological phenomena. Although renal Piezo2 expression and its alteration in rodent dehydration and hypertension models have been reported, the role of Piezo1 in hypertensive nephropathy and podocyte injury is unclear. In this study, we examined Piezo1 expression and localization in the kidneys of control mice and in those of mice with hypertensive nephrosclerosis. Uninephrectomized, aldosterone-infused, salt-loaded mice developed hypertension, albuminuria, podocyte injury, and glomerulosclerosis. RNAscope in situ hybridization revealed that Piezo1 expression was enhanced in the podocytes, mesangial cells, and distal tubular cells of these mice compared to those of the uninephrectomized, vehicle-infused control group. Piezo1 upregulation in the glomeruli was accompanied by the induction of podocyte injury-related markers, plasminogen activator inhibitor-1 and serum/glucocorticoid regulated kinase 1. These changes were reversed by antihypertensive drug. Exposure of Piezo1-expressing cultured podocytes to mechanical stretch activated Rac1 and upregulated the above-mentioned markers, which was antagonized by the Piezo1 blocker grammostola mechanotoxin #4 (GsMTx4). Administration of Piezo1-specific agonist Yoda1 mimicked the effects of mechanical stretch, which was minimized by the Yoda1-specific inhibitor Dooku1 and Rac inhibitor. Rac1 was also activated in the above-mentioned hypertensive mice, and Rac inhibitor downregulated gene expression of podocyte injury-related markers in vivo. Our results suggest that Piezo1 plays a role in mechanical stress-induced podocyte injury.
    MeSH term(s) Mice ; Animals ; Podocytes/metabolism ; Mechanotransduction, Cellular ; Kidney ; Hypertension/metabolism ; Ion Channels/metabolism ; Ion Channels/pharmacology ; Hypertension, Renal ; Nephritis
    Chemical Substances Ion Channels ; Piezo1 protein, mouse
    Language English
    Publishing date 2023-12-25
    Publishing country England
    Document type Journal Article
    ZDB-ID 1175297-x
    ISSN 1348-4214 ; 0916-9636
    ISSN (online) 1348-4214
    ISSN 0916-9636
    DOI 10.1038/s41440-023-01536-z
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  2. Article ; Online: Upregulation of Piezo2 in the mesangial, renin, and perivascular mesenchymal cells of the kidney of Dahl salt-sensitive hypertensive rats and its reversal by esaxerenone.

    Ochiai, Koji / Mochida, Yuki / Nagase, Takashi / Fukuhara, Hiroshi / Yamaguchi, Yoshihiro / Nagase, Miki

    Hypertension research : official journal of the Japanese Society of Hypertension

    2023  Volume 46, Issue 5, Page(s) 1234–1246

    Abstract: The recent discovery of mechanosensitive ion channels has promoted mechanobiological research in the field of hypertension and nephrology. We previously reported Piezo2 expression in mouse mesangial and juxtaglomerular renin-producing cells, and its ... ...

    Abstract The recent discovery of mechanosensitive ion channels has promoted mechanobiological research in the field of hypertension and nephrology. We previously reported Piezo2 expression in mouse mesangial and juxtaglomerular renin-producing cells, and its modulation by dehydration. This study aimed to investigate how Piezo2 expression is altered in hypertensive nephropathy. The effects of the nonsteroidal mineralocorticoid receptor blocker, esaxerenone, were also analyzed. Four-week-old Dahl salt-sensitive rats were randomly assigned to three groups: rats fed a 0.3% NaCl diet (DSN), rats fed a high 8% NaCl diet (DSH), and rats fed a high salt diet supplemented with esaxerenone (DSH + E). After six weeks, DSH rats developed hypertension, albuminuria, glomerular and vascular injuries, and perivascular fibrosis. Esaxerenone effectively decreased blood pressure and ameliorated renal damage. In DSN rats, Piezo2 was expressed in Pdgfrb-positive mesangial and Ren1-positive cells. Piezo2 expression in these cells was enhanced in DSH rats. Moreover, Piezo2-positive cells accumulated in the adventitial layer of intrarenal small arteries and arterioles in DSH rats. These cells were positive for Pdgfrb, Col1a1, and Col3a1, but negative for Acta2 (αSMA), indicating that they were perivascular mesenchymal cells different from myofibroblasts. Piezo2 upregulation was reversed by esaxerenone treatment. Furthermore, Piezo2 inhibition by siRNA in the cultured mesangial cells resulted in upregulation of Tgfb1 expression. Cyclic stretch also upregulated Tgfb1 in both transfections of control siRNA and Piezo2 siRNA. Our findings suggest that Piezo2 may have a contributory role in modulating the pathogenesis of hypertensive nephrosclerosis and have also highlighted the therapeutic effects of esaxerenone on salt-induced hypertensive nephropathy. Mechanochannel Piezo2 is known to be expressed in the mouse mesangial cells and juxtaglomerular renin-producing cells, and this was confirmed in normotensive Dahl-S rats. In salt-induced hypertensive Dahl-S rats, Piezo2 upregulation was observed in the mesangial cells, renin cells, and notably, perivascular mesenchymal cells, suggesting its involvement in kidney fibrosis.
    MeSH term(s) Animals ; Mice ; Rats ; Blood Pressure/physiology ; Fibrosis ; Hypertension ; Hypertension, Renal ; Ion Channels/metabolism ; Kidney/metabolism ; Rats, Inbred Dahl ; Receptor, Platelet-Derived Growth Factor beta/metabolism ; Renin/metabolism ; Sodium Chloride ; Sodium Chloride, Dietary/metabolism ; Up-Regulation
    Chemical Substances esaxerenone (N62TGJ04A1) ; Ion Channels ; Piezo2 protein, mouse ; piezo2 protein, rat ; Receptor, Platelet-Derived Growth Factor beta (EC 2.7.10.1) ; Renin (EC 3.4.23.15) ; Sodium Chloride (451W47IQ8X) ; Sodium Chloride, Dietary
    Language English
    Publishing date 2023-02-21
    Publishing country England
    Document type Journal Article
    ZDB-ID 1175297-x
    ISSN 1348-4214 ; 0916-9636
    ISSN (online) 1348-4214
    ISSN 0916-9636
    DOI 10.1038/s41440-023-01219-9
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  3. Article ; Online: Formalin-free soft embalming of human cadavers using N-vinyl-2-pyrrolidone: perspectives for cadaver surgical training and medical device development.

    Nagase, Miki / Nagase, Takashi / Tokumine, Joho / Saito, Koichiro / Sunami, Eiji / Shiokawa, Yoshiaki / Matsumura, George

    Anatomical science international

    2022  Volume 97, Issue 3, Page(s) 273–282

    Abstract: The traditional apprenticeship approach to surgical skill education for young surgeons has drastically changed to more systematic surgical training using cadavers. Cadavers fixed with formalin are not suitable for surgical training because of their ... ...

    Abstract The traditional apprenticeship approach to surgical skill education for young surgeons has drastically changed to more systematic surgical training using cadavers. Cadavers fixed with formalin are not suitable for surgical training because of their associated health hazards and overhardening. Recently, we established a formalin-free soft preservation method for human cadavers using N-vinyl-2-pyrrolidone. Since 2012, 61 cadavers have been embalmed with pyrrolidone in our institution. Tissues of pyrrolidone-embalmed cadavers are soft and pliable, and their bodies can be preserved for as long as 37 months without any signs of corruption. In this review, we introduce our recent attempts to apply pyrrolidone-embalmed cadavers in surgical and medical procedure training, including endotracheal intubation, motion physiology of the vocal folds, laparoscopic surgery, endoscopic skull base surgery, and development of novel medical devices. Future research perspectives on pyrrolidone embalming are discussed.
    MeSH term(s) Cadaver ; Embalming/methods ; Formaldehyde ; Humans ; Pyrrolidinones
    Chemical Substances Pyrrolidinones ; Formaldehyde (1HG84L3525) ; 2-pyrrolidone (KKL5D39EOL)
    Language English
    Publishing date 2022-04-22
    Publishing country Japan
    Document type Journal Article ; Review
    ZDB-ID 2079994-9
    ISSN 1447-073X ; 1447-6959 ; 0022-7722
    ISSN (online) 1447-073X
    ISSN 1447-6959 ; 0022-7722
    DOI 10.1007/s12565-022-00664-9
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  4. Article ; Online: A light-controlled phospholipase C for imaging of lipid dynamics and controlling neural plasticity.

    Kim, Yeon-Jeong / Tohyama, Suguru / Nagashima, Takashi / Nagase, Masashi / Hida, Yamato / Hamada, Shun / Watabe, Ayako M / Ohtsuka, Toshihisa

    Cell chemical biology

    2024  

    Abstract: Phospholipase C (PLC) is a key enzyme that regulates physiological processes via lipid and calcium signaling. Despite advances in protein engineering, no tools are available for direct PLC control. Here, we developed a novel optogenetic tool, light- ... ...

    Abstract Phospholipase C (PLC) is a key enzyme that regulates physiological processes via lipid and calcium signaling. Despite advances in protein engineering, no tools are available for direct PLC control. Here, we developed a novel optogenetic tool, light-controlled PLCβ (opto-PLCβ). Opto-PLCβ uses a light-induced dimer module, which directs an engineered PLC to the plasma membrane in a light-dependent manner. Our design includes an autoinhibitory capacity, ensuring stringent control over PLC activity. Opto-PLCβ triggers reversible calcium responses and lipid dynamics in a restricted region, allowing precise spatiotemporal control of PLC signaling. Using our system, we discovered that phospholipase D-mediated phosphatidic acid contributes to diacylglycerol clearance on the plasma membrane. Moreover, we extended its applicability in vivo, demonstrating that opto-PLCβ can enhance amygdala synaptic plasticity and associative fear learning in mice. Thus, opto-PLCβ offers precise spatiotemporal control, enabling comprehensive investigation of PLC-mediated signaling pathways, lipid dynamics, and their physiological consequences in vivo.
    Language English
    Publishing date 2024-03-26
    Publishing country United States
    Document type Journal Article
    ISSN 2451-9448
    ISSN (online) 2451-9448
    DOI 10.1016/j.chembiol.2024.03.001
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  5. Article ; Online: Mixed Mesonephric-like Adenocarcinoma, Clear Cell Carcinoma, and Endometrioid Carcinoma Arising from an Endometriotic Cyst.

    Nagase, Shunsuke / Saeki, Harumi / Ura, Ayako / Terao, Yasuhisa / Matsumoto, Toshiharu / Yao, Takashi

    International journal of surgical pathology

    2023  , Page(s) 10668969231213390

    Abstract: Mesonephric-like adenocarcinoma is a rare neoplasm of the uterine corpus and ovary. Unlike prototypical mesonephric adenocarcinoma of the uterine cervix, which is considered of Wolffian origin, recent evidence suggests that mesonephric-like ... ...

    Abstract Mesonephric-like adenocarcinoma is a rare neoplasm of the uterine corpus and ovary. Unlike prototypical mesonephric adenocarcinoma of the uterine cervix, which is considered of Wolffian origin, recent evidence suggests that mesonephric-like adenocarcinoma is a Mullerian tumor associated with endometriosis. We report here on a 48-year-old woman with a mixed carcinoma of the ovary that consisted of mesonephric-like adenocarcinoma, clear cell carcinoma, and endometrioid carcinoma, arising from an endometriotic cyst. The mesonephric-like adenocarcinoma consisted of cuboidal cells with vesicular nuclei presenting with a tubular, ductal, papillary, and solid architecture forming nodules. Each component showed distinct immunophenotypes that were consistent with their morphology. The mesonephric-like adenocarcinoma showed diffuse positive staining for paired box 8 and GATA binding protein 3, and negative staining for estrogen and progesterone receptors. A p53 stain exhibited wild-type immunoreactivity. A complete loss of AT-rich interactive domain-containing protein 1A (ARID1A) expression was suggestive of an
    Language English
    Publishing date 2023-11-22
    Publishing country United States
    Document type Journal Article
    ZDB-ID 1336393-1
    ISSN 1940-2465 ; 1066-8969
    ISSN (online) 1940-2465
    ISSN 1066-8969
    DOI 10.1177/10668969231213390
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  6. Article ; Online: Cephalic vein cut-down technique for severe venous spasm following axillary vein puncture at pacemaker implantation.

    Hiruma, Takashi / Nagase, Takahiko / Inoue, Kanki / Nitta, Junichi / Isobe, Mitsuaki

    Journal of cardiology cases

    2022  Volume 26, Issue 4, Page(s) 245–247

    Abstract: An 83-year-old male with complete atrioventricular block underwent dual-chamber pacemaker implantation. Venography showed normal anatomy of the left axillary vein. Following sedation with intravenous propofol, local anesthesia, and skin incision, we ... ...

    Abstract An 83-year-old male with complete atrioventricular block underwent dual-chamber pacemaker implantation. Venography showed normal anatomy of the left axillary vein. Following sedation with intravenous propofol, local anesthesia, and skin incision, we punctured the left axillary vein on the first limb. However, the guidewire could not be advanced despite blood backflow after the initial puncture. On venography, left axillary vein on the first limb totally disappeared with dilated collaterals. We diagnosed axillary vein spasm and injected 1000 μg of intravenous nitroglycerin. After 15 min, repeated venography showed slight contrast flow in the axillary vein. We alternatively punctured the axillary vein on the second limb. However, the axillary vein was spasmodically occluded again. We considered the possibility that puncture of the right axillary vein could also result in venous spasm. Since the left cephalic vein was identified after waiting time, we partially cut down the left cephalic vein and inserted guidewires into the vein. The ventricular and atrial leads were successfully implanted through sheaths in the right ventricular septum and right atrial appendage, respectively.
    Learning objective: Pacemaker implantation complicated with puncture-related axillary vein spasm is challenging. Severe venous spasms refractory to waiting time or nitroglycerin sometimes require conversion of access site. However, the bail-out technique from ipsilateral access remains unclear. Cut-down technique of the ipsilateral cephalic vein is one alternative to manage severe axillary vein spasm refractory to nitroglycerin and waiting time.
    Language English
    Publishing date 2022-06-01
    Publishing country Japan
    Document type Case Reports
    ISSN 1878-5409
    ISSN (online) 1878-5409
    DOI 10.1016/j.jccase.2022.05.005
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  7. Article: Short-time ventricular tachycardia ablation for cardiac sarcoidosis using coherent map.

    Hiruma, Takashi / Sekiguchi, Yukio / Nagase, Takahiko / Nitta, Junichi / Isobe, Mitsuaki

    Journal of arrhythmia

    2022  Volume 38, Issue 3, Page(s) 454–457

    Abstract: A 69-year-old woman with isolated cardiac sarcoidosis was hospitalized for frequent appropriate implantable converter defibrillator therapies for ventricular tachycardia (VT) despite of favorably controlled condition with oral prednisolone. The patient ... ...

    Abstract A 69-year-old woman with isolated cardiac sarcoidosis was hospitalized for frequent appropriate implantable converter defibrillator therapies for ventricular tachycardia (VT) despite of favorably controlled condition with oral prednisolone. The patient underwent urgent catheter ablation with CARTO 3D mapping system. Although the voltage map, activation map, and propagation map during VT could not visualize the tachycardia circuit, the coherent map clarified entrance and exit sites of the tachycardia circuit with slow or nonconducting (SNO) zones, which seemed like a figure-of-eight circuit. Considering the risk of VT termination or acceleration to rapid unstable VT, neither entrainment nor pacing studies were performed. The VT was terminated near the exit site of the isthmus where tiny pre-systolic potential was detected. Any diastolic potentials could not be detected. This meant that the critical isthmus might be located at the epicardium or deep incite of the left-ventricular myocardium where the coherent map showed as SNO zones. We should recognize coherent map as artificial that may represent VT circuit as if complete endocardial reentry even if not. The procedural time from mapping to termination of VT was only 22 minutes. The patient has been free from any cardiovascular events after the procedure. Coherent map might be feasible for revealing the critical isthmus of hemodynamically stable VTs without using electrophysiological techniques, including entrainment, pacing study, and voltage map during own beats, and would enable us to achieve successful VT ablation in a short time.
    Language English
    Publishing date 2022-04-06
    Publishing country Japan
    Document type Journal Article
    ZDB-ID 2696593-8
    ISSN 1883-2148 ; 1880-4276
    ISSN (online) 1883-2148
    ISSN 1880-4276
    DOI 10.1002/joa3.12706
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  8. Article ; Online: Modulated Photocurrent Spectroscopy for Determination of Electron and Hole Mobilities in Working Organic Solar Cells.

    Nojima, Hiroki / Kobayashi, Takashi / Nagase, Takashi / Naito, Hiroyoshi

    Scientific reports

    2019  Volume 9, Issue 1, Page(s) 20346

    Abstract: Carrier drift mobility is an important physical constant in the charge transport process of organic solar cells (OSCs). Although time-of-flight and space-charge-limited current techniques have been frequently utilized for mobility measurements, the ... ...

    Abstract Carrier drift mobility is an important physical constant in the charge transport process of organic solar cells (OSCs). Although time-of-flight and space-charge-limited current techniques have been frequently utilized for mobility measurements, the validity of a new method using modulation photocurrent spectroscopy is discussed in this contribution. The advantages of this method are its applicability to working OSCs with optimized device structures and the simultaneous determination of the electron and hole mobilities. These features make it possible to study the relation between the mobility balance and the solar cell characteristics, such as the power conversion efficiency, using only a single working OSC; hence, it is not necessary to fabricate electron-only and hole-only devices for mobility measurements. After carrying out numerical simulations to examine the validity of this method for mobility determination, the dependence of the mobility balance on the mixing ratio of the electron-donor and -acceptor materials is presented.
    Language English
    Publishing date 2019-12-30
    Publishing country England
    Document type Journal Article
    ZDB-ID 2615211-3
    ISSN 2045-2322 ; 2045-2322
    ISSN (online) 2045-2322
    ISSN 2045-2322
    DOI 10.1038/s41598-019-56945-3
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  9. Article ; Online: Piezo2 expression and its alteration by mechanical forces in mouse mesangial cells and renin-producing cells.

    Mochida, Yuki / Ochiai, Koji / Nagase, Takashi / Nonomura, Keiko / Akimoto, Yoshihiro / Fukuhara, Hiroshi / Sakai, Tatsuo / Matsumura, George / Yamaguchi, Yoshihiro / Nagase, Miki

    Scientific reports

    2022  Volume 12, Issue 1, Page(s) 4197

    Abstract: The kidney plays a central role in body fluid homeostasis. Cells in the glomeruli and juxtaglomerular apparatus sense mechanical forces and modulate glomerular filtration and renin release. However, details of mechanosensory systems in these cells are ... ...

    Abstract The kidney plays a central role in body fluid homeostasis. Cells in the glomeruli and juxtaglomerular apparatus sense mechanical forces and modulate glomerular filtration and renin release. However, details of mechanosensory systems in these cells are unclear. Piezo2 is a recently identified mechanically activated ion channel found in various tissues, especially sensory neurons. Herein, we examined Piezo2 expression and regulation in mouse kidneys. RNAscope in situ hybridization revealed that Piezo2 expression was highly localized in mesangial cells and juxtaglomerular renin-producing cells. Immunofluorescence assays detected GFP signals in mesangial cells and juxtaglomerular renin-producing cells of Piezo2
    MeSH term(s) Animals ; Ion Channels/genetics ; Ion Channels/metabolism ; Juxtaglomerular Apparatus/metabolism ; Kidney/metabolism ; Mesangial Cells/metabolism ; Mice ; Renin/genetics ; Renin/metabolism
    Chemical Substances Ion Channels ; Piezo2 protein, mouse ; Renin (EC 3.4.23.15)
    Language English
    Publishing date 2022-03-10
    Publishing country England
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 2615211-3
    ISSN 2045-2322 ; 2045-2322
    ISSN (online) 2045-2322
    ISSN 2045-2322
    DOI 10.1038/s41598-022-07987-7
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  10. Article ; Online: Modulated Photocurrent Spectroscopy for Determination of Electron and Hole Mobilities in Working Organic Solar Cells

    Hiroki Nojima / Takashi Kobayashi / Takashi Nagase / Hiroyoshi Naito

    Scientific Reports, Vol 9, Iss 1, Pp 1-

    2019  Volume 8

    Abstract: Abstract Carrier drift mobility is an important physical constant in the charge transport process of organic solar cells (OSCs). Although time-of-flight and space-charge-limited current techniques have been frequently utilized for mobility measurements, ... ...

    Abstract Abstract Carrier drift mobility is an important physical constant in the charge transport process of organic solar cells (OSCs). Although time-of-flight and space-charge-limited current techniques have been frequently utilized for mobility measurements, the validity of a new method using modulation photocurrent spectroscopy is discussed in this contribution. The advantages of this method are its applicability to working OSCs with optimized device structures and the simultaneous determination of the electron and hole mobilities. These features make it possible to study the relation between the mobility balance and the solar cell characteristics, such as the power conversion efficiency, using only a single working OSC; hence, it is not necessary to fabricate electron-only and hole-only devices for mobility measurements. After carrying out numerical simulations to examine the validity of this method for mobility determination, the dependence of the mobility balance on the mixing ratio of the electron-donor and –acceptor materials is presented.
    Keywords Medicine ; R ; Science ; Q
    Subject code 621
    Language English
    Publishing date 2019-12-01T00:00:00Z
    Publisher Nature Publishing Group
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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