517 results on '"Takeda, Kotaro"'
Search Results
202. Convergence of Multiple Protein Kinase Pathways of Angiotensin II Type 1 Receptor on cAMP Response Element-Binding Protein (CREB) in Rat Vascular Smooth Muscle Cells
- Author
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Ichiki, Toshihiro, primary, Funakoshi, Yuko, additional, Takeda, Kotaro, additional, and Takeshita, Akira, additional
- Published
- 2000
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203. Downregulation of Angiotensin II Type 1 Receptor by All- trans Retinoic Acid in Vascular Smooth Muscle Cells
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Takeda, Kotaro, primary, Ichiki, Toshihiro, additional, Funakoshi, Yuko, additional, Ito, Kiyoko, additional, and Takeshita, Akira, additional
- Published
- 2000
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204. Slaking Resistance of CaO Ceramics Sintered from Al2O3-Coated CaCO3 Powder
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YOSHIMATSU, Hideyuki, primary, TAKEDA, Kotaro, additional, MIURA, Yoshinari, additional, YABUKI, Tatsumi, additional, and KAWABATA, Koji, additional
- Published
- 1997
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205. CD13 promotes mesenchymal stem cell-mediated regeneration of ischemic muscle.
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Mamunur Rahman, M., Subramani, Jaganathan, Ghosh, Mallika, Denninger, Jiyeon K., Takeda, Kotaro, Fong, Guo-Hua, Carlson, Morgan E., and Shapiro, Linda H.
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MESENCHYMAL stem cells ,REGENERATION (Biology) ,CELL adhesion ,EXTRACELLULAR matrix ,CELL transplantation - Abstract
Mesenchymal stem cells (MSCs) are multipotent, tissue-resident cells that can facilitate tissue regeneration and thus, show great promise as potential therapeutic agents. Functional MSCs have been isolated and characterized from a wide array of adult tissues and are universally identified by the shared expression of a core panel of MSCs markers. One of these markers is the multifunctional cell surface peptidase CD13 that has been shown to be expressed on human and murine MSCs from many tissues. To investigate whether this universal expression indicates a functional role for CD13 in MSC biology we isolated, expanded and characterized MSCs from bone marrow of wild type (WT) and CD13
KO mice. Characterization of these cells demonstrated that both WT and CD13KO MSCs expressed the full complement of MSC markers (CD29, CD44, CD49e, CD105, Sca1), showed comparable proliferation rates and were capable of differentiating toward the adipogenic and osteogenic lineages. However, MSCs lacking CD13 were unable to differentiate into vascular cells, consistent with our previous characterization of CD13 as an angiogenic regulator. Compared to WT MSCs, adhesion and migration on various extracellular matrices of CD13KO MSCs were significantly impaired, which correlated with decreased phospho-FAK levels and cytoskeletal alterations. Crosslinking human MSCs with activating CD13 antibodies increased cell adhesion to endothelial monolayers and induced FAK activation in a time dependent manner. In agreement with these in vitro data, intramuscular injection of CD13KO MSCs in a model of severe ischemic limb injury resulted in significantly poorer perfusion, decreased ambulation, increased necrosis and impaired vascularization compared to those receiving WT MSCs. This study suggests that CD13 regulates FAK activation to promote MSC adhesion and migration, thus, contributing to MSC-mediated tissue repair. CD13 may present a viable target to enhance the efficacy of mesenchymal stem cell therapies. [ABSTRACT FROM AUTHOR]- Published
- 2014
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206. Inhibition of Tumor Necrosis Factor-α-Induced Interleukin-6 Expression by Telmisartan Through Cross-Talk of Peroxisome Proliferator-Activated Receptor-γ With Nuclear Factor κB and CCAAT/Enhancer-Binding Protein-β.
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Qingping Tian, Miyazaki, Ryohei, Ichiki, Toshihiro, Imayama, Ikuyo, Inanaga, Keita, Ohtsubo, Hideki, Yano, Kotaro, Takeda, Kotaro, and Sunagawa, Kenji
- Abstract
The article presents a study investigating whether the angiotensin II type 1 receptor antagonist telmisartan inhibits expression of the proinflammatory cytokine interleukin-6 (IL-6) in vascular smooth muscle cells. The potential benefit of using telmisartan to treat hypertension and inflammatory change in blood-vessels is also noted.
- Published
- 2009
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207. Shift of motor activation areas during recovery from hemiparesis after cerebral infarction: A longitudinal study with near-infrared spectroscopy
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Takeda, Kotaro, Gomi, Yukihiro, Imai, Itsuki, Shimoda, Nobuaki, Hiwatari, Masao, and Kato, Hiroyuki
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MOTOR ability , *CEREBRAL infarction , *SPECTRUM analysis , *CEREBRAL dominance - Abstract
Abstract: Motor functional recovery after stroke may be attributable to cerebral reorganization. We used near-infrared spectroscopy, which measures non-invasively the changes in oxy- and deoxy-hemoglobin concentrations in response to neural activation, for monitoring cerebral activation in stroke patients, and investigated the longitudinal changes in functional laterality of activations in the primary sensorimotor cortex during unilateral audio-paced (1Hz) hand movement. We examined five ischemic stroke patients (4 females and 1 male, 52–67 years old) with mild to moderate hemiparesis at acute stages and chronic stages at least 1 month later. Normal subjects (3 females and 2 males, 47–63 years old) were also included. Unilateral hand movement activated predominantly the contralateral primary sensorimotor cortex in the normal subjects and the stroke patients when they moved unaffected hand. Affected hand movements activated bilateral sensorimotor cortices early after stroke (<25 days of stroke onset), whereas the activation pattern returned toward normal at later periods (>35 days). The contralaterality index (0.34±0.12 in normal control) was reduced at early periods (0.00±0.03, p <0.01) after stroke, and returned to normal (0.35±0.24) as motor function recovered. These findings suggest that a transient increase in motor activation in the ipsilateral intact hemisphere within 1 month may play an important role in the recovery from motor dysfunction after stroke. [Copyright &y& Elsevier]
- Published
- 2007
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208. Faunal turnovers in central Pacific benthic foraminifera during the Paleocene–Eocene thermal maximum
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Takeda, Kotaro and Kaiho, Kunio
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FORAMINIFERA , *RHIZOPODA , *BOLIVINA , *PALEOCLIMATOLOGY - Abstract
Abstract: Although it is well known that the Paleocene/Eocene thermal maximum (PETM) coincided with a major benthic foraminiferal extinction event, the detailed pattern of the faunal turnover has not yet been clarified. Our high-resolution benthic foraminiferal and carbon isotope analyses at the low latitude Pacific Ocean Shatsky Rise have revealed the following record of major faunal transitions: (1) An initial turnover which involved the benthic foraminiferal extinction event (BFE). The BFE, marked by a sharp transition from Pre-extinction fauna to Disaster fauna represented by small-sized Bolivina gracilis, expresses the onset of the PETM and the abrupt extinction of about 30% of taxa. This faunal transition lasted about 45–74 kyr after the initiation of the PETM and was followed by: (2) the appearance of Opportunistic fauna represented by Quadrimorphina profunda, which existed for about 74–91 kyr after the initiation of the PETM. These two faunas, which appeared after the extinction event, are characterized by low diversity and dwarfism, possibly due to lowered oxygen condition and decreased surface productivity. The second pronounced turnover involved the gradual recovery from Opportunistic Fauna to the establishment of Recovery fauna, which coincided with the recovery about 83–91 kyr after its initiation. [Copyright &y& Elsevier]
- Published
- 2007
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209. Anomalous shifts in tropical Pacific planktonic and benthic foraminiferal test size during the Paleocene–Eocene thermal maximum
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Kaiho, Kunio, Takeda, Kotaro, Petrizzo, Maria Rose, and Zachos, James C.
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FORAMINIFERA , *BIOCHEMICAL oxygen demand , *PHOTOSYNTHETIC oxygen evolution , *NONMETALS - Abstract
Abstract: Paleocene–Eocene warming and changes in oceanic hydrography should have significantly impacted the ecology of marine microorganisms, both at the surface and on the seafloor. We analyzed several key characteristics of foraminifera from two Shatsky Rise (ODP Leg 198) cores spanning the P/E boundary including the maximum test diameters of the largest calcareous trochospiral benthic foraminifera and largest shallow-dwelling planktonic foraminifera, and the stable carbon and oxygen isotope ratios of benthic foraminifera and bulk samples. We also qualitatively constrained changes in bottom water dissolved oxygen concentrations by quantifying changes in benthic species abundances. We find warming synchronous with an unusual increase in the size of surface-water planktonic in contrast to deep-water benthic foraminifera which decrease in size. We suggest that a decline in bottom water dissolved oxygen is the primary mechanism responsible for the size reduction of Pacific deep-sea benthic foraminifera, whereas the contemporaneous size increase of surface-water planktonic foraminifera is attributed to an increase in thermal stratification and decrease in local nutrient supply. [Copyright &y& Elsevier]
- Published
- 2006
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210. Hematological, Hepatic, and Retinal Phenotypes in Mice Deficient for Prolyl Hydroxylase Domain Proteins in the Liver
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Duan, Li-Juan, Takeda, Kotaro, and Fong, Guo-Hua
- Abstract
Prolyl hydroxylase domain (PHD) proteins catalyze oxygen-dependent prolyl hydroxylation of hypoxia-inducible factor 1a and 2a, tagging them for pVHL-dependent polyubiquitination and proteasomal degradation. In this study, albumin Cre (AlbCre)–mediated, hepatocyte-specific triple disruption of Phd1, Phd2, and Phd3(Phd(1/2/3)hKO) promoted liver erythropoietin (EPO) expression 1246-fold, whereas renal EPO was down-regulated to 6.7% of normal levels. In Phd(1/2/3)hKO mice, hematocrit levels reached 82.4%, accompanied by severe vascular malformation and steatosis in the liver. In mice double-deficient for hepatic PHD2 and PHD3 (Phd(2/3)hKO), liver EPO increase and renal EPO loss both occurred but were much less dramatic than in Phd(1/2/3)hKO mice. Hematocrit levels, vascular organization, and liver lipid contents all appeared normal in Phd(2/3)hKO mice. In a chronic renal failure model, Phd(2/3)hKO mice maintained normal hematocrit levels throughout the 8-week time course, whereas floxed controls developed severe anemia. Maintenance of normal hematocrit levels in Phd(2/3)hKO mice was accomplished by sensitized induction of liver EPO expression. Consistent with such a mechanism, liver HIF-2a accumulated to higher levels in Phd(2/3)hKO mice in response to conditions causing modest systemic hypoxia. Besides promoting erythropoiesis, EPO is also known to modulate retinal vascular integrity and neovascularization. In Phd(1/2/3)hKO mice, however, neonatal retinas remained sensitive to oxygen-induced retinopathy, suggesting that local EPO may be more important than hepatic and/or renal EPO in mediating protective effects in the retina.
- Published
- 2014
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211. Improved Vascular Survival and Growth in the Mouse Model of Hindlimb Ischemia by a Remote Signaling Mechanism
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Takeda, Kotaro, Duan, Li-Juan, Takeda, Hiromi, and Fong, Guo-Hua
- Abstract
Deficiencies in prolyl hydroxylase domain proteins (PHDs) may lead to the accumulation of hypoxia-inducible factor-α proteins, the latter of which activate local angiogenic responses by paracrine mechanisms. Here, we investigate whether a keratinocyte-specific PHD deficiency may promote vascular survival and growth in a distantly located ischemic tissue by a remote signaling mechanism. We generated mice that carry a keratinocyte-specific Phd2knockout (kPhd2KO) and performed femoral artery ligation. Relative to wild-type controls, kPhd2KO mice displayed improved vascular survival and arteriogenesis in ischemic hind limbs, leading to the accelerated recovery of hindlimb perfusion and superior muscle regeneration. Similar protective effects were also seen in type 1 and type 2 diabetic mice. Molecularly, both abundance of hypoxia-inducible factor-1α protein and expression of vascular endothelial growth factor-A were increased in epidermal tissues of kPhd2KO mice, accompanied by increased plasma concentration of vascular endothelial growth factor-A. Contrary to kPhd2KO mice, which are PHD2 deficient in all skin tissues, localized kPhd2KO in hindlimb skin tissues did not have similar effects, excluding paracrine signaling as a major mechanism. Confirming the existence of remote effects, hepatocyte-specific Phd2knockout also protected hind limbs from ischemia injury. These data indicate that vascular survival and growth in ischemia-injured tissue may be stimulated by suppressing PHD2 in a remotely located tissue and may provide highly effective angiogenesis therapies without the need for directly accessing target tissues.
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- 2014
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212. A new system to measure the trunk angle and pelvis angle during wheelchair propulsion.
- Author
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Takeo, Atsumi, Okazaki, Hideto, Takeda, Kotaro, Nakagawa, Yuki, and Sonoda, Shigeru
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CYCLIC fatigue , *WHEELCHAIRS , *STERNUM , *INTRACLASS correlation , *PRESSURE sensors , *PELVIS , *RANGE of motion of joints - Abstract
Background: The number of wheelchair users is increasing as the population ages. However, there is still lack of tools to objectively assess posture during wheelchair propulsion.Objective: The purpose of this study was to develop a system to measure trunk and pelvis ROM (range of motion) while driving a wheelchair and to assess the reproducibility of the measured posture changes and cyclic fluctuations during propulsion.Methods: Motion recorders were attached to the sternum and pelvis of fifteen healthy adults, and a pressure sensor was attached to the right heel. Subjects drove a standard wheelchair using their right leg and trunk and pelvis ROM was measured in two separate sessions. To detect the trend of postural changes during propulsion, a trend curve was computed from the measured ROM using a low-pass filter and then subtracted from the measured ROM waveforms. The resulting curves were normalized and averaged, and the maximum, minimum, and amplitude of the cyclic variation during propulsion were assessed for reproducibility.Results: Intraclass correlation coefficients of the maximum, minimum, and amplitude ranged from 0.65 to 0.84.Conclusions: The proposed method can estimate the posture change and the periodic fluctuation during wheelchair propulsion with high reproducibility. [ABSTRACT FROM AUTHOR]- Published
- 2023
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213. Monolithic integration of Si-silica waveguide delay line interferometer and germanium photodetectors for 25-Gbit/s DPSK demodulator.
- Author
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Hiraki, Tatsurou, Fukuda, Hiroshi, Tsuchizawa, Tai, Kou, Rai, Nishi, Hidetaka, Takeda, Kotaro, Yamamoto, Tsuyoshi, Ishikawa, Yasuhiko, Wada, Kazumi, and Yamada, Koji
- Published
- 2014
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214. Relation between Electro-Optic Effect and Dielectric Permittivity of Ba0.5Sr0.5TiO3 Thin Films
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Takeda, Kotaro, Hoshina, Takuya, Takeda, Hiroaki, and Tsurumi, Takaaki
- Abstract
The relation between the dielectric tunability and the electro-optic (EO) effect of barium strontium titanate (Ba
0.5 Sr0.5 TiO3 ) thin film was discussed. The tunability of dielectric permittivity calculated from the complex admittance with planer electrodes reached to 53.1%, and the tunability of birefringence by EO effect was 0.6%. The birefringence change from EO effect was much lower than the tunability of dielectric permittivity. The materials with high tunability do not always exhibit high EO effect. This is concluded to arise due to the ionic mass in the EO materials.- Published
- 2013
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215. Recent Insights into the Measurement of Carbon Dioxide Concentrations for Clinical Practice in Respiratory Medicine.
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Umeda, Akira, Ishizaka, Masahiro, Ikeda, Akane, Miyagawa, Kazuya, Mochida, Atsumi, Takeda, Hiroshi, Takeda, Kotaro, Fukushi, Isato, Okada, Yasumasa, and Gozal, David
- Subjects
PARTIAL pressure ,SLEEP apnea syndromes ,RESPIRATORY quotient ,OXYGEN consumption ,CLIMATE change - Abstract
In the field of respiratory clinical practice, the importance of measuring carbon dioxide (CO
2 ) concentrations cannot be overemphasized. Within the body, assessment of the arterial partial pressure of CO2 (PaCO2 ) has been the gold standard for many decades. Non-invasive assessments are usually predicated on the measurement of CO2 concentrations in the air, usually using an infrared analyzer, and these data are clearly important regarding climate changes as well as regulations of air quality in buildings to ascertain adequate ventilation. Measurements of CO2 production with oxygen consumption yield important indices such as the respiratory quotient and estimates of energy expenditure, which may be used for further investigation in the various fields of metabolism, obesity, sleep disorders, and lifestyle-related issues. Measures of PaCO2 are nowadays performed using the Severinghaus electrode in arterial blood or in arterialized capillary blood, while the same electrode system has been modified to enable relatively accurate non-invasive monitoring of the transcutaneous partial pressure of CO2 (PtcCO2 ). PtcCO2 monitoring during sleep can be helpful for evaluating sleep apnea syndrome, particularly in children. End-tidal PCO2 is inferior to PtcCO2 as far as accuracy, but it provides breath-by-breath estimates of respiratory gas exchange, while PtcCO2 reflects temporal trends in alveolar ventilation. The frequency of monitoring end-tidal PCO2 has markedly increased in light of its multiple applications (e.g., verify endotracheal intubation, anesthesia or mechanical ventilation, exercise testing, respiratory patterning during sleep, etc.). [ABSTRACT FROM AUTHOR]- Published
- 2021
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216. Sarcoplasmic reticulum Ca2+ regulatory protein gene expression in human right atrium under hemodynamic overload.
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Sadamatsu, Kenji, Urabe, Yoshitoshi, Tsutsui, Hiroyuki, Tagawa, Hirofumi, Maruoka, Fumio, Igarashi-Saito, Keiko, Takeda, Kotaro, Kawachi, Yoshito, Yasui, Hisataka, and Takeshita, Akira
- Abstract
Sarcoplasmic reticulum (SR) Ca
2+ -adenosine triphosphatase (ATPase) mRNA expression is reduced in the failing human myocardium. However, it is not known whether SR Ca2+ -regulatory protein gene expression is altered in human myocardial tissue subjected to pressure overload or volume overload. We sought to determine whether SR Ca2+ -regulatory protein gene expression is altered in human atrial tissue subjected to mechanical overload. We obtained right atrial myocardial tissue (about 250mg) at open-heart surgery from three groups of patients: no hemodynamic overload to the right atrium (control group; 12 patients), atrial septal defect (ASD group; 8 patients), and tricuspid regurgitation (TR group; 7 patients). We measured the myocyte size, the area of interstitial fibrosis, SR Ca2+ -ATPase, and ryanodine receptor mRNA abundance. The isolated cardiocyte area and the percent area of interstitial fibrosis were in the order TR > ASD > control ( P < 0.05). The SR Ca2+ -ATPase mRNA level in TR was significantly decreased ( P = 0.004) compared with the control, whereas in the ASD group it did not differ significantly from control. There were no significant differences in ryanodine receptor mRNA levels among the three groups. SR Ca2+ -ATPase gene expression was downregulated in human atrial tissue with TR but not in ASD, which might have resulted from the differences in the degree and/or the type of hemodynamic overload to the myocardium. [ABSTRACT FROM AUTHOR]- Published
- 1999
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217. Prolyl Hydroxylase Domain Protein 2 (PHD2) Mediates Oxygen-Induced Retinopathy in Neonatal Mice
- Author
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Duan, Li-Juan, Takeda, Kotaro, and Fong, Guo-Hua
- Abstract
Retinopathy of prematurity is a major side effect of oxygen therapy for preterm infants, and is a leading cause of blindness in children. To date, it remains unclear whether the initial microvascular obliteration is triggered by degradation of hypoxia inducible factor (HIF) α proteins or by other mechanisms such as oxidative stress. Here we show that prolyl hydroxylase domain protein 2 (PHD2), an enzyme mostly responsible for oxygen-induced degradation of HIF-α proteins, plays a major role in oxygen-induced retinopathy in mice. In neonatal mice expressing normal amounts of PHD2, exposure to 75% oxygen caused significant degradation of retinal HIF-α proteins, accompanied by massive losses of retinal microvessels. PHD2 deficiency significantly stabilized HIF-1α, and to some extent HIF-2α, in neonatal retinal tissues, and protected retinal microvessels from oxygen-induced obliteration. After hyperoxia-treated neonatal mice were returned to ambient room air, retinal vasculature in PHD2-deficient mice remained mostly intact and showed very little neoangiogenesis. These findings demonstrate a close association between PHD2-dependent HIF-α degradation and oxygen-induced retinal microvascular obliteration, and imply that PHD2 may be a promising therapeutic target to prevent oxygen-induced retinopathy.
- Published
- 2011
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218. Regulation of adult erythropoiesis by prolyl hydroxylase domain proteins
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Takeda, Kotaro, Aguila, Hector L., Parikh, Nehal S., Li, Xiping, Lamothe, Katie, Duan, Li-Juan, Takeda, Hiromi, Lee, Frank S., and Fong, Guo-Hua
- Abstract
Polycythemia is often associated with erythropoietin (EPO) overexpression and defective oxygen sensing. In normal cells, intracellular oxygen concentrations are directly sensed by prolyl hydroxylase domain (PHD)–containing proteins, which tag hypoxia-inducible factor (HIF) α subunits for polyubiquitination and proteasomal degradation by oxygen-dependent prolyl hydroxylation. Here we show that different PHD isoforms differentially regulate HIF-α stability in the adult liver and kidney and suppress Epo expression and erythropoiesis through distinct mechanisms. Although Phd1−/− or Phd3−/− mice had no apparent defects, double knockout of Phd1 and Phd3 led to moderate erythrocytosis. HIF-2α, which is known to activate Epo expression, accumulated in the liver. In adult mice deficient for PHD2, the prototypic Epo transcriptional activator HIF-1α accumulated in both the kidney and liver. Elevated HIF-1α levels were associated with dramatically increased concentrations of both Epo mRNA in the kidney and Epo protein in the serum, which led to severe erythrocytosis. In contrast, heterozygous mutation of Phd2 had no detectable effects on blood homeostasis. These findings suggest that PHD1/3 double deficiency leads to erythrocytosis partly by activating the hepatic HIF-2α/Epo pathway, whereas PHD2 deficiency leads to erythrocytosis by activating the renal Epo pathway.
- Published
- 2008
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219. Unexpected abrupt coronary occlusion due to arterial media in upper arm through transradial approach.
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Shishido, Koki, Yokoyama, Hiroaki, Takeda, Kotaro, and Saito, Shigeru
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- 2019
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220. Critical Role of cAMP-response Element-binding Protein for Angiotensin II-induced Hypertrophy of Vascular Smooth Muscle Cells*
- Author
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Funakoshi, Yuko, Ichiki, Toshihiro, Takeda, Kotaro, Tokuno, Tomotake, Iino, Naoko, and Takeshita, Akira
- Abstract
We reported previously an important role of cyclic AMP-response element (CRE) for the induction of interleukin-6 gene expression by angiotensin II (AngII). We examined signaling pathways that are responsible for AngII-induced phosphorylation of CRE-binding protein (CREB) at serine 133 that is a critical marker for the activation in rat vascular smooth muscle cells (VSMC). AngII time dependently induced phosphorylation of CREB with a peak at 5 min. The AngII-induced phosphorylation of CREB was blocked by CV11974, an AngII type I receptor antagonist, suggesting that AngII type I receptor may mediate the phosphorylation of CREB. Inhibition of extracellular signal-regulated protein kinase (ERK) by PD98059 or inhibition of p38 mitogen-activated protein kinase (MAPK) by SB203580 partially inhibited AngII-induced CREB phosphorylation. A protein kinase A inhibitor, H89, also partially suppressed AngII-induced CREB phosphorylation. Inhibition of epidermal growth factor-receptor by AG1478 suppressed the AngII-induced CREB phosphorylation as well as activation of ERK and p38MAPK. Overexpression of the dominant negative form of CREB by an adenovirus vector suppressed AngII-induced c-fosexpression and incorporation of [3H]leucine to VSMC. These findings suggest that AngII may activate multiple signaling pathways involving two MAPK pathways and protein kinase A, all of which contribute to the activation of CREB. Transactivation of epidermal growth factor-receptor is also critical for AngII-induced CREB phosphorylation. Activation of CREB may be important for the regulation of gene expression and hypertrophy of VSMC induced by AngII.
- Published
- 2002
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221. 15-Deoxy-Δ12,14-prostaglandin J2and Thiazolidinediones Activate the MEK/ERK Pathway through Phosphatidylinositol 3-Kinase in Vascular Smooth Muscle Cells*
- Author
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Takeda, Kotaro, Ichiki, Toshihiro, Tokunou, Tomotake, Iino, Naoko, and Takeshita, Akira
- Abstract
Peroxisome proliferator-activated receptor (PPAR) γ belongs to the nuclear receptor superfamily of ligand-dependent transcription factors. Recent results have shown that the ligands for nuclear receptors have rapid effects so called “nongenomic” effects, which are observed within minutes after stimulation. We examined whether 15-deoxy-Δ12,14-prostaglandin J2(15-d-PGJ2) had rapid effects on cultured vascular smooth muscle cells. Phosphorylation of ERK and c-fosmRNA expression were determined by Western and Northern blot analyses, respectively. PPARγ agonists 15-d-PGJ2 and thiazolidinediones such as pioglitazone and troglitazone elicited rapid activation of ERK within 15 min and induced c-fosmRNA expression within 30 min, whereas the PPARα agonist bezafibrate failed to activate ERK. 15-d-PGJ2-induced expression of c-fosmRNA was blocked by PD98059 or U0126, two ERK kinase inhibitors, suggesting that the MEK/ERK pathway mediates 15-d-PGJ2-induced c-fosgene expression. Furthermore, pretreatment with wortmannin, an inhibitor of phosphatidylinositol 3 (PI3)-kinase, inhibited 15-d-PGJ2-induced ERK activation and c-fosmRNA expression, suggesting that PI3-kinase is involved in the process. An electrophoretic mobility shift assay showed that 15-d-PGJ2 enhanced AP-1 binding activity to AP-1 consensus sequence in a time-dependent manner. 15-d-PGJ2 increased thymidine incorporation in a PI3-kinase-dependent manner. Taken together, our findings show that 15-d-PGJ2 and thiazolidinediones activate the MEK/ERK pathway through PI3-kinase and lead to c-fosmRNA expression and DNA synthesis. These findings indicate a novel regulatory mechanism of gene expression by 15-d-PGJ2 and thiazolidinediones.
- Published
- 2001
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222. Astrocytes mediate the post‐hypoxic persistent respiratory augmentation.
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Fukushi, Isato, Takeda, Kotaro, Pokorski, Mieczyslaw, Kono, Yosuke, Yoshizawa, Masashi, Hasebe, Yohei, Nakao, Akito, Mori, Yasuo, Onimaru, Hiroshi, and Okada, Yasumasa
- Abstract
R4606 --> Acute hypoxia increases ventilation. After brief hypoxic exposure, switchback of inspired gas to room air is accompanied by short‐term potentiation of breathing, i.e., ventilation remains elevated above the baseline level. Short‐term potentiation of breathing has been thought to play a stabilizing role in control of breathing, e.g., prevention of periodic breathing. However, the mechanism of this potentiation is unclear. We aimed to test the hypothesis that astrocytes mediate this potentiation, i.e., post‐hypoxic persistent respiratory augmentation (PHRA), and performed a series of in vitro and in vivo experiments. In vitro, isolated brainstem‐spinal cord preparations of neonatal rats were superfused with artificial cerebrospinal fluid (aCSF) without or with arundic acid (500 µM), an inhibitory modulator of astrocytic function. Both groups were sequentially superfused with oxygenated (95% O2, 5% CO2) and hypoxic (95% N2, 5% CO2) aCSF for 5 min, and again with oxygenated aCSF for 17 min. Hypoxia universally increased the respiratory burst rate. Without arundic acid, the burst rate transiently decreased with reoxygenation, and then recovered to and remained at the pre‐hypoxic level until the end of the post‐hypoxic observation. Contrarily, the burst rate steadily decreased throughout the post‐hypoxic phase with arundic acid, declining below the pre‐hypoxic level. In vivo, the hypoxic ventilatory response was investigated by whole‐body plethysmography in unanesthetized adult mice. The animals breathed room air, hypoxic gas (7% O2, 93% N2) for 2 min, and again room air for 10 min before and after i.p. administration of low (100 mg/kg) and high (300 mg/kg) doses of arundic acid. Minute ventilation in the post‐hypoxic recovery was maintained above the pre‐hypoxic level without arundic acid. However, it was suppressed with arundic acid. Notably with high dose arundic acid, it decreased below the pre‐hypoxic level. Finally, we investigated the significance of the astrocytic TRPA1 channel, which is a ventilatory hypoxic sensor, in the PHRA using astrocyte‐specific Trpa1 knockout (asTrpa1‐/‐) and floxed Trpa1 (Trpa1f/f) mice. Although the PHRA was observed in both Trpa1f/f and as Trpa1‐/‐ mice, it was weaker in asTrpa1‐/‐ as compared to Trpa1f/f mice. This observation indicates that the astrocytic TRPA1 channel plays a role in the PHRA but this by itself is not sufficient, suggesting the existence of additional key factors. These in vitro and in vivo experimental findings collectively demonstrate that astrocytes mediate the PHRA partially through the TRPA1 channel. [ABSTRACT FROM AUTHOR]
- Published
- 2021
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223. Daily Fluctuation in the Drug-Resistance of Tubercle Bacilli in Sputa
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NAGAYAMA, Yoshitame, MOCHIZUKI, Koji, TAKEDA, Kotaro, DOI, Kazuhiko, FUJITA, Seiichi, and YOSHIDA, Tamotsu
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493.8 - Published
- 1956
224. Role of microglia in blood pressure and respiratory responses to acute hypoxic exposure in rats
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Yoshizawa, Masashi, Fukushi, Isato, Takeda, Kotaro, Kono, Yosuke, Hasebe, Yohei, Koizumi, Keiichi, Ikeda, Keiko, Pokorski, Mieczyslaw, Toda, Takako, and Okada, Yasumasa
- Abstract
Microglia modulate cardiorespiratory activities during chronic hypoxia. It has not been clarified whether microglia are involved in the cardiorespiratory responses to acute hypoxia. Here we investigated this issue by comparing cardiorespiratory responses to two levels of acute hypoxia (13% O2for 4 min and 7% O2for 5 min) in conscious unrestrained rats before and after systemic injection of minocycline (MINO), an inhibitor of microglia activation. MINO increased blood pressure but not lung ventilation in the control normoxic condition. Acute hypoxia stimulated cardiorespiratory responses in MINO-untreated rats. MINO failed to significantly affect the magnitude of hypoxia-induced blood pressure elevation. In contrast, MINO tended to suppress the ventilatory responses to hypoxia. We conclude that microglia differentially affect cardiorespiratory regulation depending on the level of blood oxygenation. Microglia suppressively contribute to blood pressure regulation in normoxia but help maintain ventilatory augmentation in hypoxia, which underscores the dichotomy of central regulatory pathways for both systems.
- Published
- 2022
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225. A patient with bilateral medial medullary infarction: Clinical and magnetic resonance imaging findings
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Sako, Rikitaro, Yamamoto, Satoshi, Takeda, Kotaro, Wakatabi, Masahiro, Daira, Minoru, Hondera, Tetsuichi, Oota, Takayuki, Fujii, Ami, Okamoto, Yoshitaka, Sugiyama, Satoshi, and Ozasa, Yoshifumi
- Abstract
•We report a case with bilateral medial medullary infarctions.•The patient demonstrated hemiplegia, sensory dysfunction, ataxia, and dysphagia.•BPAS-MRI revealed that the tunica externa of the vertebral artery was intact.•TOF-MRA and BPAS-MRI could help improve the accuracy of diagnosis.
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- 2021
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226. Influence of hematoma volume and age on cognitive functions and ADL after putaminal hemorrhage.
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Watanabe, Makoto, Takeda, Kotaro, Maeshima, Shinichiro, Suzuki, Takaji, and Sonoda, Shigeru
- Abstract
Background and Objective: After cerebral hemorrhage, cognitive functions and activities of daily living (ADL) are affected by various factors, including hematoma volume and patient age. In the present study, we investigated the effect of age and hematoma volume on cognitive functions and on ADL.Methods: The sample comprised 274 patients (183 men and 91 women; mean age 58.2 ± 12.5 years) with putaminal hemorrhage who were hospitalized in a convalescent rehabilitation ward. Hematoma volume was estimated from computed tomography imaging at stroke onset. Cognitive functions were evaluated using Raven's Colored Progressive Matrices test (RCPM) and the Mini-Mental State Examination (MMSE) at hospital admission, while ADL score was assessed at discharge using the Functional Independence Measure motor subscale (FIM-M). In the present study, we classified the patients into six groups according to whether they were non-elderly or elderly (cutoff age, 60 years) and whether their hematoma was small, medium, or large (cutoff volumes, 20 and 40 mL, respectively). Subsequently, the scores on the RCPM, MMSE, and FIM-M were compared among the groups.Results: In both age groups, patients with a larger hematoma volume had lower RCPM and MMSE scores. Patients <60 years old exhibited different trends in their RCPM and MMSE scores, such that the RCPM score showed a step-wise decrease according to hematoma volume, while a difference in the MMSE score was only observed at the 20 mL boundary. Most of the younger patients (<60 years of age) attained high FIM-M scores at discharge, as long as their hematoma volume was either medium or small (<40 mL). This age group had higher RCPM scores on admission, which may have contributed to their higher FIM-M scores on discharge.Conclusions: In the present study, we demonstrated that advancing age increases the effect of hematoma volume on RCPM and MMSE scores and identified differences in the effects observed on these two scores. Thus, it may be important to use the RCPM alongside the MMSE for patient assessment. [ABSTRACT FROM AUTHOR]- Published
- 2020
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227. Relationship between Hematoma Volume and Motor Impairment in Putaminal Hemorrhage.
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Ohnishi, Hitoshi, Takeda, Kotaro, Watanabe, Makoto, Maeshima, Shinichiro, and Sonoda, Shigeru
- Abstract
Purpose: Computed tomography (CT) is used for initial assessment of patients with suspected stroke. Motor outcome prediction using the initial CT image is important for clinical rehabilitation. However, there is inconsistency in the results reported by the few publications on hematoma volume and motor outcomes in patients with putaminal hemorrhage. To clarify the direction of hematoma and relationship between the hematoma volume and motor outcomes in patients with putaminal hemorrhage using an initial CT image, we evaluated the volume of direction of hematoma in 170 patients in the subacute phase after putaminal hemorrhage using CT at stroke onset.Methods: The patients were divided into 5 groups according to the direction of the hematoma. For each group, Spearman's correlation coefficients were calculated to investigate the relationship between hematoma volume and motor outcomes. Motor outcomes were assessed using the motor items of Stroke Impairment Assessment Set, which are impairment indexes for the distal and proximal functions of the upper and lower extremities after stroke.Results: Hematoma volume was significantly correlated with all the motor items in the group whose hematoma extended to the posterior limb of the internal capsule alone (Bonferroni corrected P <.05). On the other hand, significant correlations between hematoma volume and motor outcomes could not be found in almost all the other groups.Conclusions: Motor outcome after putaminal hemorrhage can be predicted by evaluating the progression of hematoma to the corticospinal tract and its volume using CT images at stroke onset. [ABSTRACT FROM AUTHOR]- Published
- 2020
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228. SIPULEUCEL-T IMMUNOTHERAPY-RELATED CARDIOMYOPATHY: A NOVEL OBSERVATION.
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Moey, Melissa YY, Takeda, Kotaro, Ardhanari, Sivakumar, Prenshaw, Karyn, Marcu, Constantin, and Kreeger, Wayne
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CARDIOMYOPATHIES , *HEART failure , *ATRIAL fibrillation - Published
- 2020
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229. Cell Responses of the Ventrolateral Medulla to PAR1 Activation and Changes in Respiratory Rhythm in Newborn Rat En Bloc Brainstem-Spinal Cord Preparations.
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Onimaru, Hiroshi, Fukushi, Isato, Ikeda, Keiko, Yazawa, Itaru, Takeda, Kotaro, Okada, Yasumasa, and Izumizaki, Masahiko
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NEWBORN infants , *MEMBRANE potential , *CEREBROSPINAL fluid , *RATS , *ASTROCYTES , *BRAIN stem , *RESPIRATORY muscles - Abstract
• We report the effects of PAR1-selective agonist TFLLR on respiratory rhythm. • TFLLR induced robust activation of astrocytes in the rostral ventrolateral medulla. • Medullary respiratory-related neurons tended to hyperpolarize during TFLLR. • Respiratory rhythm was slightly depressed during TFLLR. Proteinase-activated receptor-1 (PAR1) is expressed in astrocytes of various brain regions, and its activation is involved in the modulation of neuronal activity. Here, we report effects of PAR1 selective agonist TFLLR on respiratory rhythm generation in brainstem-spinal cord preparations. Preparations were isolated from newborn rats (P0-P4) under deep isoflurane anesthesia and were transversely cut at the rostral medulla. Preparations were superfused with artificial cerebrospinal fluid (25–26 °C), and inspiratory C4 ventral root activity was monitored. The responses to TFLLR of cells close to the cut surface were detected by calcium imaging or membrane potential recordings. Application of 10 μM TFLLR (4 min) induced a rapid and transient increase of calcium signal in cells of the ventrolateral respiratory regions of the medulla. More than 88% of responding cells (223/254 cells from 13 preparations) were also activated by low (0.2 mM) K+ solution, suggesting that they were astrocytes. Immunohistochemical examination demonstrated that PAR1 was expressed on many astrocytes. Respiratory-related neurons in the medulla were transiently hyperpolarized (-1.8 mV) during 10 μM TFLLR application, followed by weak membrane depolarization after washout. C4 burst rate decreased transiently in response to application of TFLLR, followed by a slight increase. The inhibitory effect was partially blocked by 50 μM theophylline. In conclusion, activation of astrocytes via PAR1 resulted in a decrease of inspiratory C4 burst rate in association with transient hyperpolarization of respiratory-related neurons. After washout, slow and weak excitatory responses appeared. Adenosine may be partially involved in the inhibitory effect of PAR1 activation. [ABSTRACT FROM AUTHOR]
- Published
- 2023
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230. Comprehensive photonics-electronics convergent simulation and its application to high-speed electronic circuit integration on a Si/Ge photonic chip
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Srivastava, Atul K., Dingel, Benjamin B., Dutta, Achyut K., Takeda, Kotaro, Honda, Kentaro, Takeya, Tsutomu, Okazaki, Kota, Hiraki, Tatsurou, Tsuchizawa, Tai, Nishi, Hidetaka, Kou, Rai, Fukuda, Hiroshi, Usui, Mitsuo, Nosaka, Hideyuki, Yamamoto, Tsuyoshi, and Yamada, Koji
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- 2015
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231. Reduction of global interference of scalp-hemodynamics in functional near-infrared spectroscopy using short distance probes.
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Sato, Takanori, Nambu, Isao, Takeda, Kotaro, Aihara, Takatsugu, Yamashita, Okito, Isogaya, Yuko, Inoue, Yoshihiro, Otaka, Yohei, Wada, Yasuhiro, Kawato, Mitsuo, Sato, Masa-aki, and Osu, Rieko
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HEMODYNAMICS , *BRAIN imaging , *NEAR infrared spectroscopy , *FUNCTIONAL magnetic resonance imaging , *TASK performance , *LINEAR statistical models - Abstract
Functional near-infrared spectroscopy (fNIRS) is used to measure cerebral activity because it is simple and portable. However, scalp-hemodynamics often contaminates fNIRS signals, leading to detection of cortical activity in regions that are actually inactive. Methods for removing these artifacts using standard source–detector distance channels (Long-channel) tend to over-estimate the artifacts, while methods using additional short source–detector distance channels (Short-channel) require numerous probes to cover broad cortical areas, which leads to a high cost and prolonged experimental time. Here, we propose a new method that effectively combines the existing techniques, preserving the accuracy of estimating cerebral activity and avoiding the disadvantages inherent when applying the techniques individually. Our new method accomplishes this by estimating a global scalp-hemodynamic component from a small number of Short-channels, and removing its influence from the Long-channels using a general linear model (GLM). To demonstrate the feasibility of this method, we collected fNIRS and functional magnetic resonance imaging (fMRI) measurements during a motor task. First, we measured changes in oxygenated hemoglobin concentration (∆ Oxy-Hb) from 18 Short-channels placed over motor-related areas, and confirmed that the majority of scalp-hemodynamics was globally consistent and could be estimated from as few as four Short-channels using principal component analysis. We then measured ∆ Oxy-Hb from 4 Short- and 43 Long-channels. The GLM identified cerebral activity comparable to that measured separately by fMRI, even when scalp-hemodynamics exhibited substantial task-related modulation. These results suggest that combining measurements from four Short-channels with a GLM provides robust estimation of cerebral activity at a low cost. [ABSTRACT FROM AUTHOR]
- Published
- 2016
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232. Dual orexin receptor blocker suvorexant attenuates hypercapnic ventilatory augmentation in mice.
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Fukushi, Isato, Yokota, Shigefumi, Takeda, Kotaro, Terada, Jiro, Umeda, Akira, Yoshizawa, Masashi, Kono, Yosuke, Hasebe, Yohei, Onimaru, Hiroshi, Pokorski, Mieczyslaw, and Okada, Yasumasa
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SUBSTANCE P receptors , *SLEEP apnea syndromes , *RESPIRATORY insufficiency , *MICE - Abstract
[Display omitted] • Orexin is involved in respiratory control. • Orexin is involved in shaping the hypercapnic ventilatory chemosensitivity. • Suvorexant does not affect ventilation in room air or hypoxic ventilatory responses. • Suvorexant significantly attenuates hypercapnic ventilatory augmentation. • Suvorexant calls for caution in use in patients with hypercapnic respiratory failure. Suvorexant (Belsomra(R)), a dual orexin receptor antagonist widely used in the treatment of insomnia, inhibits the arousal system in the brain. However, the drug's ventilatory effects have not been fully explored. This study aims to investigate the expression of orexin receptors in respiratory neurons and the effects of suvorexant on ventilation. Immunohistology of brainstem orexin receptor OX2R expression was performed in adult mice (n = 4) in (1) rostral ventral respiratory group (rVRG) neurons projecting to the phrenic nucleus (PhN) retrogradely labeled by Fluoro-Gold (FG) tracer, (2) neurons immunoreactive for paired like homeobox 2b (Phox2b) in the parafacial respiratory group/retrotrapezoid nucleus (pFRG/RTN), and (3) neurons immunoreactive for neurokinin 1 receptor (NK1R) and somatostatin (SST) in the preBötzinger complex (preBötC). Additionally, we measured in vivo ventilatory responses to hyperoxic hypercapnia (5% CO 2) and hypoxia (10% O 2) before and after suvorexant pretreatment (10 and cumulative 100 mg/kg) in unrestrained mice (n = 10) in a body plethysmograph. We found the OX2R immunoreactive materials in pFRG/RTN Phox2b and preBötC NK1R/SST immunoreactive neurons but not in FG-labeled rVRG neurons, which suggests the involvement of orexin in respiratory control. Further, suvorexant expressly suppressed the hypercapnic ventilatory augmentation, otherwise unaffecting ventilation. Central orexin is involved in shaping the hypercapnic ventilatory chemosensitivity. Suppression of hypercapnic ventilatory augmentation by the orexin receptor antagonist suvorexant calls for caution in its use in pathologies that may progress to hypercapnic respiratory failure, or sleep-disordered breathing. Clinical trials are required to explore the role of targeted pharmacological inhibition of orexin in ventilatory pathologies. [ABSTRACT FROM AUTHOR]
- Published
- 2022
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233. A Quantitative and Qualitative Assessment of Frozen Section Diagnosis Accuracy and Deferral Rate Across Organ Systems.
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Mohamed, Anas, Hassan, Muhammad Masood, Zhong, Wen, Kousar, Aisha, Takeda, Kotaro, Donthi, Deepak, Rizvi, Areeba, Majeed, Marwan, Younes, Ahmed I, Ali, Ahlam, Sutton, Ann, Murray, Gina, Thayyil, Abdullah, Fallon, John, and Geisinger, Kim
- Abstract
Objectives: Monitoring of frozen section diagnostic performance provides an important quality improvement measure.Methods: Surgical specimens involving a frozen section diagnosis over a 3-year period were retrospectively reviewed. Glass slides were reviewed on cases with discordance. Discordance and deferral rates were calculated.Results: Of 3,675 frozen section diagnoses included, 96 (2.7%) were discordant with the final diagnosis. Additionally, 114 frozen section diagnoses (3.1%) were deferred. The organ-specific discordance rates were lowest in breast and genitourinary specimens and highest for pancreas, lymph node, and gynecologic specimens. Deferral rates were highest in musculoskeletal, breast, and hepatobiliary cases and lowest in thyroid, parathyroid, and neuropathology cases. Discordance was explained by block-sampling error (45%), specimen-sampling error (27%), or interpretation error (27%). Discordant frozen section diagnoses from gynecologic specimens were responsible for 81% of specimen-sampling errors; frozen section diagnoses of lymph nodes, head and neck, and pancreas were responsible for 54% of interpretation errors; 51% of block-sampling errors involved lymph node evaluation for metastatic carcinoma.Conclusions: Careful gross evaluation and microscopic examination of multiple levels should minimize specimen-sampling error and block-sampling error, respectively. Periodic review of accuracy and deferral rates may help reduce errors and improve the overall performance of this essential procedure. [ABSTRACT FROM AUTHOR]- Published
- 2022
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234. Effect of chronic ethanol treatment on μ-opioid receptor function, interacting proteins and morphine-induced place preference.
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Shibasaki, Masahiro, Watanabe, Kenjiro, Takeda, Kotaro, Itoh, Toshimasa, Tsuyuki, Tomohisa, Narita, Minoru, Mori, Tomohisa, and Suzuki, Tsutomu
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OPIOID receptors , *ALCOHOLISM treatment , *PROTEIN-protein interactions , *MORPHINE abuse , *MOLECULAR biology , *CENTRAL nervous system , *WESTERN immunoblotting - Abstract
Rationale: Both the acute and chronic consumption of ethanol have been reported to modify several molecular events in the central nervous system, and the endogenous μ-opioid receptor system is involved in the reinforcing/rewarding effects of ethanol. Objectives: The present study was designed to clarify the effects of chronic ethanol treatment on cellular processes involving μ-opioid receptor and the development of morphine-induced rewarding effects. Methods: Male C57BL/6J mice were continuously treated with a liquid diet containing 3.0 w/ v ethanol. The direct involvement of μ-opioid receptor functions in the activation of G-proteins and changes in protein levels in the lower midbrain of mice after chronic treatment with ethanol were investigated by a [S] GTPγS binding assay and Western blotting, respectively. The rewarding effects of morphine (5 mg/kg) under treatment with ethanol were measured by the conditioned place preference paradigm. Results: The function of μ-opioid receptor was increased by treatment with ethanol in the lower midbrain using [S] GTPγS binding assay. Furthermore, the GRK2 protein level was significantly increased by treatment with ethanol. Chronic treatment with ethanol enhanced the rewarding effects of morphine. On the other hand, this enhancement of the rewarding effects of morphine by ethanol treatment was significantly inhibited by the GRK2 inhibitor β-adrenergic receptor kinase 1 inhibitor. Conclusions: The present study demonstrated that chronic treatment with ethanol enhanced the rewarding effects of morphine by up-regulating functional changes in μ-opioid receptor, mediated by GRK2. [ABSTRACT FROM AUTHOR]
- Published
- 2013
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235. Cortical current source estimation from electroencephalography in combination with near-infrared spectroscopy as a hierarchical prior
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Aihara, Takatsugu, Takeda, Yusuke, Takeda, Kotaro, Yasuda, Wataru, Sato, Takanori, Otaka, Yohei, Hanakawa, Takashi, Honda, Manabu, Liu, Meigen, Kawato, Mitsuo, Sato, Masa-aki, and Osu, Rieko
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ELECTROENCEPHALOGRAPHY , *NEAR infrared spectroscopy , *BAYESIAN analysis , *MAGNETOENCEPHALOGRAPHY , *COMPUTER simulation , *MAGNETIC resonance imaging of the brain - Abstract
Abstract: Previous simulation and experimental studies have demonstrated that the application of Variational Bayesian Multimodal EncephaloGraphy (VBMEG) to magnetoencephalography (MEG) data can be used to estimate cortical currents with high spatio-temporal resolution, by incorporating functional magnetic resonance imaging (fMRI) activity as a hierarchical prior. However, the use of combined MEG and fMRI is restricted by the high costs involved, a lack of portability and high sensitivity to body-motion artifacts. One possible solution for overcoming these limitations is to use a combination of electroencephalography (EEG) and near-infrared spectroscopy (NIRS). This study therefore aimed to extend the possible applications of VBMEG to include EEG data with NIRS activity as a hierarchical prior. Using computer simulations and real experimental data, we evaluated the performance of VBMEG applied to EEG data under different conditions, including different numbers of EEG sensors and different prior information. The results suggest that VBMEG with NIRS prior performs well, even with as few as 19 EEG sensors. These findings indicate the potential value of clinically applying VBMEG using a combination of EEG and NIRS. [Copyright &y& Elsevier]
- Published
- 2012
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236. Integrity of the prolyl hydroxylase domain protein 2:erythropoietin pathway in aging mice
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Li, Xiping, Sutherland, Scott, Takeda, Kotaro, Fong, Guo-Hua, and Lee, Frank S.
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HYPOXEMIA , *PROLINE hydroxylase , *ERYTHROPOIETIN , *LABORATORY mice , *TRANSCRIPTION factors , *ERYTHROCYTES , *POLYCYTHEMIA , *AGING - Abstract
Abstract: The central transcriptional response to hypoxia is mediated by the prolyl hydroxylase domain protein (PHD):hypoxia inducible factor (HIF) pathway. In this pathway, PHD prolyl hydroxylates and thereby negatively regulates the α-subunit of the transcription factor HIF (HIF-α). An important HIF target gene is that for erythropoietin (EPO), which controls red cell mass. Recent studies have identified PHD2 as the critical PHD isoform regulating the EPO gene. Other studies have shown that the inducibility of the HIF pathway diminishes as a function of age. Thus, an important question is whether the PHD2:EPO pathway is altered in the aging. Here, we employed a mouse line with a globally-inducible Phd2 conditional knockout allele to examine the integrity of the Phd2:Epo axis in young (six to eight months old) and aging (sixteen to twenty months old) mice. We find that acute global deletion of Phd2 results in a robust erythrocytosis in both young and aging mice, with both age groups showing marked extramedullary hematopoiesis in the spleen. Epo mRNA is dramatically upregulated in the kidney, but not in the liver, in both age groups. Conversely, other Hif targets, including Vegf, Pgk1, and Phd3 are upregulated in the liver but not in the kidney in both age groups. These findings have implications for targeting this pathway in the aging. [Copyright &y& Elsevier]
- Published
- 2010
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237. A study on the immediate effects of neuromuscular electrical stimulation on the corticospinal tract excitability of the infraspinatus muscle.
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Endo, Naoto, Ishii, Daisuke, Ishibashi, Kiyoshige, Yamamoto, Satoshi, Takeda, Kotaro, and Kohno, Yutaka
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EVOKED potentials (Electrophysiology) , *STATISTICS , *NEURAL pathways , *ELECTRIC stimulation , *DESCRIPTIVE statistics , *DATA analysis software , *DATA analysis , *ELECTROMYOGRAPHY , *ROTATOR cuff - Abstract
BACKGROUND: Rotator cuff muscles are structurally and functionally different from other upper-limb muscles because they are responsible for glenohumeral joint stability. Neuromuscular electrical stimulation (NMES) induces excitability changes (increase or decrease) of the corticospinal tract (CST) in the peripheral muscles, such as those of the finger. However, it remains unclear whether similar results are obtained when targeting the infraspinatus muscle, which has properties that differ from other muscles, in healthy subjects. OBJECTIVE: We investigated the immediate effects of NMES on the corticospinal excitability of the infraspinatus muscle, a rotator cuff muscle, in healthy subjects. METHODS: Thirteen healthy right-handed men (mean age: 26.77 ± 2.08 years) participated in this study. The motor evoked potentials (MEPs) and the maximum compound muscle action potential (Mmax) were recorded before NMES to the right infraspinatus and within 15 minutes after the end of the NMES. RESULTS: NMES on the infraspinatus muscle significantly increased its MEP amplitude (Pre: 0.45 mV [0.33–0.48]; Post: 0.54 mV [0.46–0.60] (median [lower quartile to higher quartile]); p = 0.005) but had no effect on Mmax (Pre: 2.95 mV [2.59–4.71]; Post: 3.35 mV [2.76–4.72]; p = 0.753). CONCLUSIONS: NMES application to the infraspinatus muscle increases CST excitability without producing immediate changes in the neuromuscular junction or muscle hypertrophy. [ABSTRACT FROM AUTHOR]
- Published
- 2021
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238. Structural and functional connectivity from the dorsomedial hypothalamus to the ventral medulla as a chronological amplifier of sympathetic outflow.
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Kono, Yosuke, Yokota, Shigefumi, Fukushi, Isato, Arima, Yosuke, Onimaru, Hiroshi, Okazaki, Shuntaro, Takeda, Kotaro, Yazawa, Itaru, Yoshizawa, Masashi, Hasebe, Yohei, Koizumi, Keiichi, Pokorski, Mieczyslaw, Toda, Takako, Sugita, Kanji, and Okada, Yasumasa
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FUNCTIONAL connectivity , *HYPOTHALAMUS , *CHRONOLOGY , *CARDIOVASCULAR system , *TYROSINE hydroxylase - Abstract
Psychological stress activates the hypothalamus, augments the sympathetic nervous output, and elevates blood pressure via excitation of the ventral medullary cardiovascular regions. However, anatomical and functional connectivity from the hypothalamus to the ventral medullary cardiovascular regions has not been fully elucidated. We investigated this issue by tract-tracing and functional imaging in rats. Retrograde tracing revealed the rostral ventrolateral medulla was innervated by neurons in the ipsilateral dorsomedial hypothalamus (DMH). Anterograde tracing showed DMH neurons projected to the ventral medullary cardiovascular regions with axon terminals in contiguity with tyrosine hydroxylase-immunoreactive neurons. By voltage-sensitive dye imaging, dynamics of ventral medullary activation evoked by electrical stimulation of the DMH were analyzed in the diencephalon-lower brainstem-spinal cord preparation of rats. Although the activation of the ventral medulla induced by single pulse stimulation of the DMH was brief, tetanic stimulation caused activation of the DMH sustained into the post-stimulus phase, resulting in delayed recovery. We suggest that prolonged excitation of the DMH, which is triggered by tetanic electrical stimulation and could also be triggered by psychological stress in a real life, induces further prolonged excitation of the medullary cardiovascular networks, and could contribute to the pathological elevation of blood pressure. The connectivity from the DMH to the medullary cardiovascular networks serves as a chronological amplifier of stress-induced sympathetic excitation. This notion will be the anatomical and pathophysiological basis to understand the mechanisms of stress-induced sustained augmentation of sympathetic activity. [ABSTRACT FROM AUTHOR]
- Published
- 2020
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239. Ability of electrical stimulation therapy to improve the effectiveness of robotic training for paretic upper limbs in patients with stroke.
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Miyasaka, Hiroyuki, Orand, Abbas, Ohnishi, Hitoshi, Tanino, Genichi, Takeda, Kotaro, and Sonoda, Shigeru
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ARM , *STROKE patients , *ELECTRIC stimulation , *ROBOTICS , *PARALYSIS - Abstract
We investigated whether untriggered neuromuscular electrical stimulation (NMES) can increase the effectiveness of shoulder and elbow robotic training in patients with hemiparesis. Thirty subacute stroke patients were randomly equally allocated to robot only (RO) and robot and electrical stimulation (RE) groups. During training, shoulder and elbow movements were trained by operating the robotic arm with the paretic arm, and the robotic device helped to move the arm. In the RE group, the anterior deltoid and triceps brachii muscles were electrically stimulated at sub-motor threshold intensity. Training was performed (approximately 1 h/day, 5 days/week for 2 weeks) in addition to regular rehabilitation. Active range of motion (ROM) values of shoulder flexion and abduction, and Fugl-Meyer assessment (FMA) scores were measured before and after training. Active shoulder ROM was significantly better after than before training in the RE group; however, no such improvement was noted in the RO group. FMA scores were significantly better in both groups, and there was no significant difference between the groups. Untriggered NMES might increase the effectiveness of shoulder and elbow robotic training in patients with hemiparesis. Additionally, NMES at a sub-motor threshold during robotic training might facilitate activation of paretic muscles, resulting in paralysis improvement. [ABSTRACT FROM AUTHOR]
- Published
- 2016
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240. Prenatal stress induces vulnerability to stress together with the disruption of central serotonin neurons in mice.
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Miyagawa, Kazuya, Tsuji, Minoru, Ishii, Daisuke, Takeda, Kotaro, and Takeda, Hiroshi
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NEUROBEHAVIORAL disorders , *PSYCHOLOGICAL stress , *FETAL behavior , *PATHOLOGICAL physiology , *LABORATORY mice , *BIOCHEMISTRY - Abstract
A growing body of evidence suggests that prenatal stress increases the vulnerability to neuropsychiatric disorders. On the other hand, the ability to adapt to stress is an important defensive function of a living body, and disturbance of this stress adaptability may be related, at least in part, to the pathophysiology of stress-related psychiatric disorders. The aim of the present study was to clarify the relationship between exposure to prenatal stress and the ability to adapt to stress in mice. Naive and prenatally stressed mice were exposed to repeated restraint stress for 60 min/day for 7 days. After the final exposure to restraint stress, the emotionality of mice was evaluated in terms of exploratory activity, i.e., total distance moved as well as the number and duration of rearing and head-dipping behaviors, using an automatic hole-board apparatus. A single exposure to restraint stress for 60 min induced a decrease in head-dipping behavior in the hole-board test. This acute emotional stress response disappeared in naive mice that had been exposed to repeated restraint stress for 60 min/day for 7 days, which confirmed the development of stress adaptation. In contrast, prenatally stressed mice did not develop this stress adaptation, and still showed a decrease in head-dipping behavior after the repeated exposure to restraint stress. Biochemical studies showed that the rate-limiting enzyme in 5-HT synthesis, tryptophan hydroxylase, was increased in raphe obtained from stress-adapted mice. In contrast, a decrease in tryptophan hydroxylase was observed in stress-maladaptive mice. In addition, the transcription factor Lmx1b, which is essential for differentiation and the maintenance of normal functions in central 5-HT neurons, was decreased in the embryonic hindbrain and adult raphe of prenatally stressed mice. These findings suggest that exposure to excessive prenatal stress may induce a vulnerability to stress and disrupt the development of 5-HT neurons. [ABSTRACT FROM AUTHOR]
- Published
- 2015
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241. Deletion of prolyl hydroxylase domain proteins (PHD1, PHD3) stabilizes hypoxia inducible factor-1 alpha, promotes neovascularization, and improves perfusion in a murine model of hind-limb ischemia.
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Rishi, Muhammad T., Selvaraju, Vaithinathan, Thirunavukkarasu, Mahesh, Shaikh, Inam A., Takeda, Kotaro, Fong, Guo-Hua, Palesty, J. Alexander, Sanchez, Juan A., and Maulik, Nilanjana
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PROLINE hydroxylase , *PROTEIN stability , *HYPOXIA-inducible factor 1 , *NEOVASCULARIZATION , *PERFUSION , *LABORATORY mice , *ISCHEMIA - Abstract
Background There is an emerging focus on investigating innovative therapeutic molecules that can potentially augment neovascularization in order to treat peripheral arterial disease (PAD). Although prolyl hydroxylase domain proteins 1 and 3 (PHD1 and PHD3) may modulate angiogenesis via regulation of hypoxia inducible factor-1α (HIF-1α), there has been no study directly addressing their roles in ischemia-induced vascular growth. We hypothesize that PHD1 −/− or PHD3 −/− deficiency might promote angiogenesis in the murine hind-limb ischemia (HLI) model. Study design Wild type (WT), PHD1 −/− and PHD3 −/− male mice aged 8–12 weeks underwent right femoral artery ligation. Post-procedurally, motor function assessment and laser Doppler imaging were periodically performed. The mice were euthanized after 28 days and muscles were harvested. Immunohistochemical analysis was performed to determine the extent of angiogenesis by measuring capillary and arteriolar density. VEGF expression was quantified by enzyme-linked immunosorbent assay (ELISA). Bcl-2 and HIF-1α were analyzed by immunofluorescence. Fibrosis was measured by picrosirius red staining. Results PHD1 −/− and PHD3 −/− mice showed significantly improved recovery of perfusion and motor function score when compared to WT after femoral artery ligation. These mice also exhibited increased capillary and arteriolar density, capillary/myocyte ratio along with decreased fibrosis compared to WT. VEGF, Bcl-2 and HIF-1α expression increased in PHD1 −/− and PHD3 −/− mice compared to WT. Conclusions Taken together these results suggest that PHD1 and PHD3 deletions promote angiogenesis in ischemia-injured tissue, and may present a promising therapeutic strategy in treating PAD. [ABSTRACT FROM AUTHOR]
- Published
- 2015
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242. Repeated exposure to stress stimuli during ethanol consumption prolongs withdrawal-induced emotional abnormality in mice.
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Kato, Hideaki, Tsuji, Minoru, Miyagawa, Kazuya, Takeda, Kotaro, and Takeda, Hiroshi
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PHYSIOLOGICAL stress , *STIMULUS & response (Biology) , *ETHANOL , *EMOTIONS , *LABORATORY mice , *LIQUID diet , *COMPUTER network resources - Abstract
Abstract: The present study was designed to ascertain the influence of repeated exposure to stress on the development of ethanol dependence in mice. Mice were chronically treated with 3% ethanol for 7 days, with or without exposure to restraint stress for 1h/day. A significant loss of body weight was observed in the ethanol plus stress group compared with the other groups. In the ethanol plus stress group, mice exhibited persistent piloerection, which is considered to be a withdrawal sign that reflects emotion, after the discontinuation of ethanol treatment. The ethanol plus stress group also showed a marked increase in the intake of liquid diet, which is considered to be trying to avoid an unpleasant ethanol-withdrawal symptom, during ethanol withdrawal. In the hole-board test, a significant decrease in head-dipping behavior was observed in both the ethanol alone and ethanol plus stress groups at 6h after the discontinuation of ethanol treatment. This abnormal emotion was recovered in the ethanol alone group, but not in the ethanol plus stress group, at 48h after the discontinuation of ethanol treatment. These results suggest that repeated exposure to stress may affect the development of ethanol dependence and prolong the expression of withdrawal-induced emotional abnormality. [Copyright &y& Elsevier]
- Published
- 2013
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243. Inhibition of MDM2 attenuates neointimal hyperplasia via suppression of vascular proliferation and inflammation.
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Hashimoto, Toru, Ichiki, Toshihiro, Ikeda, Jiro, Narabayashi, Eriko, Matsuura, Hirohide, Miyazaki, Ryohei, Inanaga, Keita, Takeda, Kotaro, and Sunagawa, Kenji
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HYPERPLASIA , *INFLAMMATION , *CARCINOGENESIS , *GENETIC toxicology , *BLOOD platelets , *CELL cycle , *LYMPHOCYTES - Abstract
Aims Tumour protein p53 plays an important role in the vascular remodelling process as well as in oncogenesis. p53 is negatively regulated by murine double minute 2 (MDM2). A recently developed MDM2 inhibitor, nutlin-3, is a non-genotoxic activator of the p53 pathway. So far, the effect of MDM2 inhibition on vascular remodelling has not been elucidated. We therefore investigated the effect of nutlin-3 on neointima formation. Methods and results Nutlin-3 up-regulated p53 and its downstream target p21 in vascular smooth muscle cells (VSMCs). DNA synthesis assay and flow cytometric analysis revealed that nutlin-3 inhibited platelet-derived growth factor (PDGF)-induced VSMC proliferation by cell cycle arrest. This inhibitory effect was abrogated in p53-siRNA-transfected VSMCs. Furthermore, nutlin-3 inhibited PDGF-stimulated VSMC migration. Treatment with nutlin-3 attenuated neointimal hyperplasia at 28 days after vascular injury in mice, associated with up-regulation of p53 and p21. BrdU incorporation was decreased at 14 days after injury in nutlin-3-treated mice. TUNEL assay showed that nutlin-3 did not exaggerate apoptosis of the injured vessels. Infiltration of macrophages and T-lymphocytes and mRNA expression of chemokine (C-C motif) ligand-5, interleukin-6, and intercellular adhesion molecule-1 were decreased in the injured vessels of nutlin-3-treated mice. Nutlin-3 suppressed NF-κB activation in VSMCs, but not in p53-siRNA-transfected VSMCs. Conclusions The MDM2 antagonist nutlin-3 inhibits VSMC proliferation, migration, and NF-κB activation, and also attenuates neointimal hyperplasia after vascular injury in mice, which is associated with suppression of vascular cell proliferation and an inflammatory response. Targeting MDM2 might be a potential therapeutic strategy for the treatment of vascular proliferative diseases. [ABSTRACT FROM AUTHOR]
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- 2011
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244. Acetylcholinesterase inhibitors attenuate atherogenesis in apolipoprotein E-knockout mice
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Inanaga, Keita, Ichiki, Toshihiro, Miyazaki, Ryohei, Takeda, Kotaro, Hashimoto, Toru, Matsuura, Hirohide, and Sunagawa, Kenji
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ATHEROSCLEROSIS treatment , *ACETYLCHOLINESTERASE , *LABORATORY mice , *HEART failure , *DRUG administration , *TUMOR necrosis factors , *AORTA , *CYTOKINES , *OXIDATIVE stress - Abstract
Abstract: Objective: Donepezil, a reversible acetylcholinesterase inhibitor, improves cognitive function of Alzheimer''s disease. Stimulation of cholinergic system was reported to improve long-term survival of rats with chronic heart failure and to attenuate inflammatory response in mice with lipopolysaccharide-induced sepsis. We sought to determine whether the pharmacological stimulation of cholinergic system by donepezil reduces atherogenesis in apolipoprotein (Apo) E-knockout (KO) mice. Methods and results: Male ApoE-KO mice (10-week-old) were fed a high-fat diet and received infusion of angiotensin (Ang) II (490ng/kg/day). Donepezil or physostigmine was administered for 4 weeks. Oral administration of donepezil (5mg/kg/day) or infusion of physostigmine (2mg/kg/day) significantly attenuated atherogenesis (Oil Red O-positive area) without significant changes in heart rate, blood pressure and total cholesterol levels. Administration of donepezil suppressed expression of monocyte chemoattractant protein-1 and tumor necrosis factor-α, NADPH oxidase activity and production of reactive oxygen species in the aorta. Conclusion: The present study revealed novel anti-oxidative and anti-atherosclerotic effects of pharmacological stimulation of cholinergic system by donepezil. Donepezil may be used as a novel therapeutics for the atherosclerotic cardiovascular diseases. [Copyright &y& Elsevier]
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- 2010
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245. Coherence analysis of the calcium activity of putative astrocytic and neuronal cells on the L5 ventral horn and neural output in activated lumbar CPG networks.
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Yazawa, Itaru, Okazaki, Shuntaro, Yokota, Shigefumi, Takeda, Kotaro, Fukushi, Isato, Yoshizawa, Masashi, Onimaru, Hiroshi, and Okada, Yasumasa
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CENTRAL pattern generators , *NEURAL circuitry , *CENTRAL nervous system , *PROTEASE-activated receptors , *INTRACELLULAR calcium - Abstract
• Coherence analysis of the calcium activity of L5 ventral cells and neural output in fictive locomotion. • Calcium activity of astrocytes and neurons synchronized with locomotor-like activity in a certain frequency range. • These cells might be active with certain time lags to maintain synaptic function and metabolism in activated lumbar CPG networks. Astrocytes are thought to play a crucial role in providing structure to the spinal cord and maintaining efficient synaptic function and metabolism because their fine processes envelop the synapses of neurons and form many neuronal networks within the central nervous system (CNS). To investigate whether putative astrocytes and putative neurons distributed on the ventral horn play a role in the modulation of lumbar locomotor central pattern generator (CPG) networks, we used extracellular recording and optical imaging techniques and recorded the neural output from the left L5 ventral root and the calcium activity of putative astrocytes and neurons in the L5 ventral horn at the same time when activating an isolated L1–L5 spinal cord preparation from rats aged 0–2 days. Optical measurements detected cells that showed a fluorescence intensity change under all experimental conditions, namely, (1) 5-HT + NMDA, (2) TTX, and (3) TTX + Low K+. These cells were semiautomatically identified using an in-house MATLAB-based program, as putative astrocytes and neurons according to the cell classification, i.e., increased or decreased fluorescence intensity change (ΔF/F0), and subjective judgment based on their soma size. Coherence and its phase were calculated according to the calcium activity of the putative astrocytes and putative neurons, and neural output was calculated during fictive locomotion with in-house MATLAB-based programs. We found that the number of putative astrocytes activated by applying low K+ tends not to differ from that activated by applying the protease-activated receptor 1 (PAR1) selective agonist TFLLR-NH 2 (TFLLR). Moreover, the calcium activity of several putative astrocytes and neurons synchronized with locomotor-like activity at a frequency range below 0.5 Hz and the time lag between peaks of cellular calcium activity and locomotor-like activity ranged from −1000 to + 1000 ms. These findings presumably indicates that these putative astrocytes and neurons in the left L5 ventral horn require −1000 to + 1000 ms to communicate with lumbar CPG networks and maintain efficient synaptic function and metabolism in activated lumbar CPG networks. This finding suggests the possibility that putative astrocytic and neuronal cells in the L5 ventral horn contribute to generating the rhythms and patterns of locomotor-like activity by activated CPG networks in the first to fifth lumbar spinal cord. [ABSTRACT FROM AUTHOR]
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- 2022
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246. O2-Dependent Protein Internalization Underlies Astrocytic Sensing of Acute Hypoxia by Restricting Multimodal TRPA1 Channel Responses.
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Uchiyama, Makoto, Nakao, Akito, Kurita, Yuki, Fukushi, Isato, Takeda, Kotaro, Numata, Tomohiro, Tran, Ha Nam, Sawamura, Seishiro, Ebert, Maximilian, Kurokawa, Tatsuki, Sakaguchi, Reiko, Stokes, Alexander J., Takahashi, Nobuaki, Okada, Yasumasa, and Mori, Yasuo
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TRP channels , *UBIQUITIN ligases , *HYPOXEMIA , *UBIQUITINATION , *HYPOXIA-inducible factor 1 , *BLOOD proteins - Abstract
Hypoxia sensors are essential for regulating local oxygen (O 2) homeostasis within the body. This is especially pertinent within the CNS, which is particularly vulnerable to O 2 deprivation due to high energetic demand. Here, we reveal hypoxia-monitoring function exerted by astrocytes through an O 2 -regulated protein trafficking mechanism within the CNS. Strikingly, cultured mouse astrocytes isolated from the parafacial respiratory group (pFRG) and retrotrapezoid nucleus (RTN) region are capable of rapidly responding to moderate hypoxia via the sensor cation channel transient receptor potential (TRP) A1 but, unlike multimodal sensory neurons, are inert to hyperoxia and other TRPA1 activators (carbon dioxide, electrophiles, and oxidants) in normoxia. Mechanistically, O 2 suppresses TRPA1 channel activity by protein internalization via O 2 -dependent proline hydroxylation and subsequent ubiquitination by an E3 ubiquitin ligase, NEDD4-1 (neural precursor cell-expressed developmentally down-regulated protein 4). Hypoxia inhibits this process and instantly accumulates TRPA1 proteins at the plasma membrane, inducing TRPA1-mediated Ca2+ influx that triggers ATP release from pFRG/RTN astrocytes, potentiating respiratory center activity. Furthermore, astrocyte-specific Trpa1 disruption in a mouse brainstem-spinal cord preparation impedes the amplitude augmentation of the central autonomic respiratory output during hypoxia. Thus, reversible coupling of the TRPA1 channels with O 2 -dependent protein translocation allows astrocytes to act as acute hypoxia sensors in the medullary respiratory center. • TRPA1 in pFRG/RTN astrocytes selectively monitors moderate hypoxia • During hypoxia, TRPA1 acutely accumulates in the plasma membrane of pFRG/RTN astrocytes • TRPA1 is reversibly coupled with O 2 -dependent internalization via PHD and NEDD4-1 • Hypoxia triggers astrocytic ATP release via TRPA1 modulating respiratory center Hypoxia sensors regulate local O 2 homeostasis within the brain. Uchiyama et al. show that reversible coupling of TRPA1 with O 2 -dependent protein translocation allows astrocytes to act as acute hypoxia sensors. Hypoxia-induced TRPA1 activity accelerates ATP release from pFRG/RTN astrocytes in the medulla to modulate respiratory activity. [ABSTRACT FROM AUTHOR]
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- 2020
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247. Intermittent hypoxia, energy expenditure, and visceral adipocyte recovery.
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Umeda, Akira, Miyagawa, Kazuya, Mochida, Atsumi, Takeda, Hiroshi, Takeda, Kotaro, Okada, Yasumasa, and Gozal, David
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CONTINUOUS positive airway pressure , *WEIGHT gain , *HYPOXEMIA , *BODY weight , *SLEEP apnea syndromes - Abstract
• Mechanisms of weight gain in OSAS patients after CPAP initiation were evaluated in mice. • Post-IH normoxic recovery visceral white adipocytes were significantly enlarged. • Adipocyte enlargement did not seem to involve decreases in energy expenditure. Body weight of patients with obstructive sleep apnea after initiation of nasal continuous positive airway pressure appears to increase. We hypothesized that intermittent hypoxia (IH) will decrease energy expenditure (EE), and that normoxic recovery will lead to body weight gains. C57BL/6 J male mice were exposed to either 12 h/day of mild IH (alternating F I O 2 -10-11% and 21%; 640 s cycle), or severe IH (F I O 2 -6-7%-21%; 180 s cycle) or sham IH daily for 4 or 8 weeks. After exposures, EE was evaluated while mice were kept under normoxia for 5 weeks and organ histology was evaluated. EE was not decreased by IH. However, visceral white adipocyte size after normoxic recovery was significantly increased in severe IH in an intensity-dependent manner. Our hypothesis that IH would decrease EE was not corroborated. However, IH and normoxic recovery seem to promote severity-dependent enlargement of visceral adipocytes, likely reflecting altered energy preservation mechanisms induced by IH. [ABSTRACT FROM AUTHOR]
- Published
- 2020
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248. Higher sensitivity of pericardial fluid cytology than biopsy in malignant effusions with potential explanation of false-negative cytology: A multi-institutional analysis.
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Takeda K, Gereg C, Liu X, Ma W, Bearse M, Tang H, Delfino I, Huang E, Lin X, Chandler JB, and Wang H
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- Humans, Female, Male, Aged, Middle Aged, Retrospective Studies, False Negative Reactions, Adult, Aged, 80 and over, Biopsy, Neoplasms pathology, Neoplasms diagnosis, Sensitivity and Specificity, Cytodiagnosis methods, Pericardial Fluid, Pericardial Effusion pathology, Pericardial Effusion diagnosis
- Abstract
Objective: Malignant pericardial effusions are associated with a poor prognosis. Pericardial fluid cytology and pericardial biopsy are the primary methods for diagnosis. This study aimed to conduct a multi-institutional analysis to compare the diagnostic sensitivity of cytology and biopsy, and to investigate potential explanations for false-negative results in cytology., Methods: A retrospective review of pericardial fluid cytology cases with concurrent biopsy was conducted across four different institutions. Results were compared using standard statistical methods with attention to sensitivity and histologic distribution. False-negative cytology cases were investigated for further exploration., Results: A total of 309 cases were collected, of which 99 (32.0%) were confirmed malignant through repeat sampling or clinical history. Pericardial fluid cytology and biopsy identified 84 and 64 malignant cases, respectively. Our findings confirmed significantly higher sensitivity of cytology compared to biopsy (84.8% vs 65.7%). The most common sites of origin were lung, breast, and gastrointestinal, with adenocarcinoma being the most prevalent histologic subtype. Histologic review of 12 false-negative cytology cases revealed three key explanations; lymphoma was the most common missed diagnosis (33.3%); fibrinous pericarditis obscures neoplastic cells on the pericardial surface; and pericardial involvement can be seen without extension into the pericardial space., Conclusion: This study demonstrated diagnostic superiority of pericardial fluid cytology over biopsy in the evaluation of malignant pericardial effusions. We identified several limitations in fluid cytology causing false negatives. In the context of an underlying malignancy with pericardial effusion, pathologists should consider immunohistochemistry studies to aid on the diagnosis., (© 2024 John Wiley & Sons Ltd.)
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- 2025
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249. Cytomorphological characteristics of low-grade papillary urothelial carcinoma in voided urine samples: Distinction from benign and high-grade papillary urothelial carcinoma.
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Takeda K, Adeniran AJ, Levi AW, Tang H, and Cai G
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- Humans, Male, Female, Middle Aged, Aged, Aged, 80 and over, Cytodiagnosis methods, Adult, Retrospective Studies, Urine cytology, Urinary Bladder Neoplasms pathology, Urinary Bladder Neoplasms urine, Urinary Bladder Neoplasms diagnosis, Urologic Neoplasms pathology, Urologic Neoplasms urine, Urologic Neoplasms diagnosis, Neoplasm Grading, Carcinoma, Papillary pathology, Carcinoma, Papillary urine, Carcinoma, Papillary diagnosis, Urothelium pathology
- Abstract
Objective: Given its frequent recurrence and the potential for high-grade transformation, accurate diagnosis of low-grade papillary urothelial carcinoma (LGPUC) in urine cytology is clinically important. We attempted to identify cytomorphologic features in urine samples, which could be helpful for the identification of LGPUC., Methods: We conducted a retrospective review of voided urine specimens collected from patients with histopathologic diagnoses of LGPUC. Their cytomorphological features were compared with those from patients with benign conditions and high-grade papillary urothelial carcinoma (HGPUC)., Results: A total of 115 voided urine specimens were evaluated, including 30 benign, 41 LGPUC, and 44 HGPUC cases. In LGPUC, 18 cases (44%) were diagnosed as atypical, a proportion significantly higher than that observed in benign cases (4 cases, 13%), while the remaining 23 cases (56%) were diagnosed as negative. LGPUC urine samples tended to have higher cellularity than benign cases, but the difference was not statistically significant. Three cytological features, namely nuclear enlargement, higher nuclear-to-cytoplasmic (N/C) ratio, and presence of small cell clusters, were statistically more prevalent in LGPUC compared to benign cases, although the changes were relatively subtle. In contrast, cytomorphological distinction between LGPUC and HGPUC was evident, as high cellularity, nuclear enlargement, hyperchromasia, high N/C ratio, irregular nuclear membrane, and apoptosis were significantly more prevalent in HGPUC cases., Conclusions: Several cytomorphologic features in voided urine samples were more prevalent in cases with LGPUC, albeit not observed in all instances. Since these alterations were relatively subtle, meticulous attention to these cytomorphologic details is crucial to suggest the possibility of LGPUC., (© 2024 John Wiley & Sons Ltd.)
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- 2024
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250. Persistence of post-stress blood pressure elevation requires activation of astrocytes.
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Hasebe Y, Yokota S, Fukushi I, Takeda K, Yoshizawa M, Onimaru H, Kono Y, Sugama S, Uchiyama M, Koizumi K, Horiuchi J, Kakinuma Y, Pokorski M, Toda T, Izumizaki M, Mori Y, Sugita K, and Okada Y
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- Animals, Rats, Male, Hypertension physiopathology, Hypertension metabolism, Rats, Sprague-Dawley, Heart Rate, Neurons metabolism, Brain metabolism, Proto-Oncogene Proteins c-fos metabolism, Astrocytes metabolism, Blood Pressure, Stress, Psychological physiopathology
- Abstract
The reflexive excitation of the sympathetic nervous system in response to psychological stress leads to elevated blood pressure, a condition that persists even after the stress has been alleviated. This sustained increase in blood pressure, which may contribute to the pathophysiology of hypertension, could be linked to neural plasticity in sympathetic nervous activity. Given the critical role of astrocytes in various forms of neural plasticity, we investigated their involvement in maintaining elevated blood pressure during the post-stress phase. Specifically, we examined the effects of arundic acid, an astrocytic inhibitor, on blood pressure and heart rate responses to air-jet stress. First, we confirmed that the inhibitory effect of arundic acid is specific to astrocytes. Using c-Fos immunohistology, we then observed that psychological stress activates neurons in cardiovascular brain regions, and that this stress-induced neuronal activation was suppressed by arundic acid pre-treatment in rats. By evaluating astrocytic process thickness, we also confirmed that astrocytes in the cardiovascular brain regions were activated by stress, and this activation was blocked by arundic acid pre-treatment. Next, we conducted blood pressure measurements on unanesthetized, unrestrained rats. Air-jet stress elevated blood pressure, which remained high for a significant period during the post-stress phase. However, pre-treatment with arundic acid, which inhibited astrocytic activation, suppressed stress-induced blood pressure elevation both during and after stress. In contrast, arundic acid had no significant impact on heart rate. These findings suggest that both neurons and astrocytes play integral roles in stress-induced blood pressure elevation and its persistence after stress, offering new insights into the pathophysiological mechanisms underlying hypertension., (© 2024. The Author(s).)
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- 2024
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