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"Abe, Ryo"
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Development of a Spherical Shell Robot with Rolling and Legged Locomotion
2023
Herein, we propose a spherical shell robot that can roll and move on its legs, and develop a prototype of the robot. Recently, there has been a growing demand for robots that can move freely and gather information on rough terrains, such as disaster sites, which are not accessible to humans. The robot developed here has two types of mobilities: rolling movement using a spherical shape and walking movement using its legs. Because the morphological transformation does not require recombination of parts, it can be reversibly performed via remote control. Therefore, the robot can select the movement method according to the environment, and reach the target point reliably even on uneven terrains, such as a disaster site. We designed a mechanism that enabled the transformation of the form and devised an operation method. Accordingly, a prototype was developed and tested. A rolling test on flat ground confirmed that the robot can roll over 5.0 m and its speed could be controlled using a gyro sensor. The leg locomotion test confirmed that the robot can turn and move straight ahead without turning over. In addition, we also conducted experiments, such as sudden stops and remote morphological deformation, to confirm the operation of the robot during rolling.
Journal Article
Oncogenic Kit signals on endolysosomes and endoplasmic reticulum are essential for neoplastic mast cell proliferation
2014
Kit is a receptor-type tyrosine kinase found on the plasma membrane. It can transform mast cells through activating mutations. Here, we show that a mutant Kit from neoplastic mast cells from mice, Kit(D814Y), is permanently active and allows cells to proliferate autonomously. It does so by activating two signalling pathways from different intracellular compartments. Mutant Kit from the cell surface accumulates on endolysosomes through clathrin-mediated endocytosis, which requires Kit’s kinase activity. Kit(D814Y) is constitutively associated with phosphatidylinositol 3-kinase, but the complex activates Akt only on the cytoplasmic surface of endolysosomes. It resists destruction because it is under-ubiquitinated. Kit(D814Y) also appears in the endoplasmic reticulum soon after biosynthesis, and there, can activate STAT5 aberrantly. These mechanisms of oncogenic signalling are also seen in rat and human mast cell leukemia cells. Thus, oncogenic Kit signalling occurs from different intracellular compartments, and the mutation acts by altering Kit trafficking as well as activation.
Activating mutations of the tyrosine kinase Kit are commonly found in mast cell neoplasms and gastrointestinal stromal tumours. Here the authors show that mutant Kit, through the activation of PI3K and STAT3 pathways, elicits proliferative and survival signals from endolysosomes and from the endoplasmic reticulum.
Journal Article
FLT3-ITD transduces autonomous growth signals during its biosynthetic trafficking in acute myelogenous leukemia cells
2021
FMS-like tyrosine kinase 3 (FLT3) in hematopoietic cells binds to its ligand at the plasma membrane (PM), then transduces growth signals.
FLT3
gene alterations that lead the kinase to assume its permanently active form, such as
internal tandem duplication (ITD)
and
D835Y
substitution, are found in 30–40% of acute myelogenous leukemia (AML) patients. Thus, drugs for molecular targeting of FLT3 mutants have been developed for the treatment of AML. Several groups have reported that compared with wild-type FLT3 (FLT3-wt), FLT3 mutants are retained in organelles, resulting in low levels of PM localization of the receptor. However, the precise subcellular localization of mutant FLT3 remains unclear, and the relationship between oncogenic signaling and the mislocalization is not completely understood. In this study, we show that in cell lines established from leukemia patients, endogenous FLT3-ITD but not FLT3-wt clearly accumulates in the perinuclear region. Our co-immunofluorescence assays demonstrate that Golgi markers are co-localized with the perinuclear region, indicating that FLT3-ITD mainly localizes to the Golgi region in AML cells. FLT3-ITD biosynthetically traffics to the Golgi apparatus and remains there in a manner dependent on its tyrosine kinase activity. Tyrosine kinase inhibitors, such as quizartinib (AC220) and midostaurin (PKC412), markedly decrease FLT3-ITD retention and increase PM levels of the mutant. FLT3-ITD activates downstream in the endoplasmic reticulum (ER) and the Golgi apparatus during its biosynthetic trafficking. Results of our trafficking inhibitor treatment assays show that FLT3-ITD in the ER activates STAT5, whereas that in the Golgi can cause the activation of AKT and ERK. We provide evidence that FLT3-ITD signals from the early secretory compartments before reaching the PM in AML cells.
Journal Article
Enrichment of circulating tumor cells in tumor-bearing mouse blood by a deterministic lateral displacement microfluidic device
by
Suzuki, Toshihiro
,
Abe, Ryo
,
Konishi, Tomoki
in
Animals
,
Biological and Medical Physics
,
Biomedical Engineering and Bioengineering
2015
Concentration of real tumor cells leaking into blood from cancer was attempted by a deterministic lateral displacement (DLD) microfluidic device. Spiked cultured cell line tumor cells are often used to verify performance of the circulating tumor cells (CTCs) separation methods. Cultured tumor cells are obviously larger than most of hematocytes and considered not to be appropriate as CTC mimics, while there is uncertainty in identifying real CTCs from clinical samples and there is no practical way to examine CTCs leakage into benign cells during the sorting. In this work, blood samples were prepared from tumor-bearing mice whose tumors were induced by implanting cells with GFP expression to living mice. Therefore, CTCs were identified by their fluorescence emission. We succeeded in the enrichment of tumor cells to 0.05% from the blood, in which CTCs were negligibly detected among three million blood cells, and little loss of CTCs was observed.
Journal Article
Achievement of adequate nutrition contributes to maintaining the skeletal muscle area in patients with sepsis undergoing early mobilization: a retrospective observational study
by
Abe, Ryo
,
Sugo, Masayuki
,
Shimazui, Takashi
in
Clinical Nutrition
,
Comorbidity
,
computed tomography
2024
Background
The onset of muscle loss in critically ill patients, known as intensive care unit-acquired weakness (ICU-AW), worsens their outcomes. Preventing muscle loss, which begins in the early phase of critical illness, is crucial in patient care. Adequate nutrition management may contribute to maintaining muscles; however, its evidence in patients with sepsis is insufficient. This study aimed to analyze the association between energy achievement rate in the first 7-days of critical care and muscle area changes evaluated by computed tomography (CT).
Methods
This was a retrospective observational study. Patients with sepsis admitted to the intensive care (ICU) of a tertiary care hospital in Japan were included. They were divided into three groups according to tertiles of the first 7-day energy achievement rate calculated using administered energy doses and basement energy expenditure. Skeletal muscle area (SMA) and changes in SMA were determined by CT on ICU admission and within days 7–10 of ICU admission. SMA maintenance was defined as SMA change ≥ 100%. Logistic regression analyses were performed to analyze the association of energy achievement rate with SMA changes (primary outcome) and in-hospital 28-day mortality (secondary outcome).
Results
Patients (
n
= 93) were classified into low, middle, and high groups according to their 7-day energy achievement rate (median rates, 16.8%, 38.8%, and 73.4%, respectively). The CT scans showed that SMA decreased between the CT scans in the low and middle groups, whereas it was maintained in the high group (median changes, -8.5%, -11.7%, and 2.8%, respectively). Univariate and multivariate logistic regression analyses showed that high energy achievement rate was significantly associated with SMA maintenance (reference, middle energy achieved group; univariate, odds ratio [95% confidence interval] 6.23 [2.04–19.10],
P
= 0.0013; multivariate, odds ratio [95% confidence interval] 5.92 [1.90–18.40],
P
= 0.0021). There was no significant difference in the association between energy achievement rate and mortality among the three groups.
Conclusions
Our study found that a fulfillment of energy achievement in the first 7 days of hospitalization was associated with maintenance of muscle area. Thus, satisfying adequate energy should be considered even in patients with sepsis.
Journal Article
Impact of surface functional group modification on cellular internalization and cytotoxicity of silica nanoparticles
2025
Background
Silica nanoparticles (SiO
2
NPs) are widely used in industrial products. Surface modification of SiO
2
NPs is one of the promising strategies to develop safer nanomaterials by design. The present study was designed to determine the effects of amino or carboxyl functionalization of rhodamine-labeled SiO
2
NPs on cellular uptake and cytotoxicity.
Methods
In the in vivo arm of the study, male mice were randomly divided into seven groups (n = 6, each) and exposed to either amino (NH
2
)- or carboxyl (COOH)-functionalized, or non-functionalized (OH)-rhodamine-labeled SiO
2
NPs at 2 or 10 mg/kg bw, or endotoxin-free water as a control, by pharyngeal aspiration. At 24 h after administration, the mice were euthanized and bronchoalveolar lavage fluid (BALF) was collected for differential cell count and assessment of silica nanoparticle uptake using confocal microscopy. In the in vitro arm of the study, murine RAW264.7 macrophages were exposed to NH
2
-or COOH-functionalized or OH- rhodamine-labeled SiO
2
NPs. Nonspecific caspase inhibitor, necroptosis inhibitor, pyroptosis inhibitor and autophagy inhibitor were used to determine the roles of cell death signaling in cytotoxicity.
Results
The in vivo studies demonstrated significant increase in lung weight at 2 and 10 mg/kg bw by OH-SiO
2
NPs but not the other two SiO
2
NPs. At 10 mg/kg bw, COOH-SiO2NPs induced a significant increase in BALF macrophages, whereas OH- SiO
2
NPs significantly decreased macrophages. OH-SiO
2
NPs at 2 mg/kg bw and NH
2
- and COOH-SiO
2
NPs at 10 mg/kg bw significantly increased BALF neutrophiles. The in vitro studies showed greater NH
2
-SiO
2
NPs internalization into RAW264.7 macrophages than OH-SiO
2
NPs, while OH-SiO
2
NPs induced cytotoxicity and upregulation of IL-1β and TNF-α to greater extent than the other two types. Co-treatment with pan-caspase inhibitor and necroptosis inhibitor attenuated (3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium) (MTS) cytotoxicity of OH-SiO
2
NPs.
Conclusion
NH
2
- or COOH-functionalization reduced the harmful changes observed with OH- SiO
2
NPs, which included increase in lung weight and BALF neutrophils at low dose in mice as well as decrease in cell viability and upregulation of proinflammatory cytokines in RAW264.7 macrophages. The results suggested that OH-SiO
2
NPs-induced cytotoxicity against macrophages was mediated at least in part through apoptotic/necroptotic signaling but was not related to internalization of particles. The results imply possible development of safer silica nanoparticles by amino- or carboxyl-functionalization of their silanols.
Journal Article
Acceptability, Safety, and Feasibility of Transnasal and Peroral Ultrathin Endoscopy Using GAGLESS Mouthpieces: A Prospective Randomized Trial
2024
Esophagogastroduodenoscopy (EGD) is an effective screening method for early detection of gastric cancer. The GAGLESS mouthpiece has a structure that widens the pharyngeal cavity and suppresses the pharyngeal reflex. This study aimed to investigate the acceptability, safety, and feasibility of transnasal and peroral ultrathin endoscopy using GAGLESS mouthpieces (Clinical Trial Number: UMIN000036922).
This study was a multicenter, prospective, randomized, open-label trial performed using a questionnaire. The study included 101 consecutive patients who visited the participating medical institutions between June 2019 and March 2022 (median age=47 years, range=24-87 years; all male). Patients aged ≥20 years at the time of consent acquisition who were the first to undergo EGD were included in the study. The primary endpoint was the degree of distress during EGD, as determined using a visual analog scale (VAS).
The VAS score during endoscopic passage through the pharynx was significantly better in the transnasal endoscopy group than in the oral endoscopy group (2.420 vs. 4.092, p=0.001). There was no significant difference in the VAS scores between the two groups during anesthesia or throughout the examination. Compared with nasal endoscopy, oral endoscopy with a GAGLESS mouthpiece did not reduce the VAS score but did significantly improve gastric visibility.
For patients in whom there was difficulty in inserting a nasal endoscope, using a GAGLESS mouthpiece rather than a conventional mouthpiece may be more useful in reducing pain.
Journal Article
M-COPA suppresses endolysosomal Kit-Akt oncogenic signalling through inhibiting the secretory pathway in neoplastic mast cells
by
Tasaki, Yasutaka
,
Abe, Ryo
,
Horikawa, Keita
in
1-Phosphatidylinositol 3-kinase
,
Activation
,
Acute myeloid leukemia
2017
Gain-of-function mutations in Kit receptor tyrosine kinase result in the development of a variety of cancers, such as mast cell tumours, gastrointestinal stromal tumours (GISTs), acute myeloid leukemia, and melanomas. The drug imatinib, a selective inhibitor of Kit, is used for treatment of mutant Kit-positive cancers. However, mutations in the Kit kinase domain, which are frequently found in neoplastic mast cells, confer an imatinib resistance, and cancers expressing the mutants can proliferate in the presence of imatinib. Recently, we showed that in neoplastic mast cells that endogenously express an imatinib-resistant Kit mutant, Kit causes oncogenic activation of the phosphatidylinositol 3-kinase-Akt (PI3K-Akt) pathway and the signal transducer and activator of transcription 5 (STAT5) but only on endolysosomes and on the endoplasmic reticulum (ER), respectively. Here, we show a strategy for inhibition of the Kit-PI3K-Akt pathway in neoplastic mast cells by M-COPA (2-methylcoprophilinamide), an inhibitor of this secretory pathway. In M-COPA-treated cells, Kit localization in the ER is significantly increased, whereas endolysosomal Kit disappears, indicating that M-COPA blocks the biosynthetic transport of Kit from the ER. The drug greatly inhibits oncogenic Akt activation without affecting the association of Kit with PI3K, indicating that ER-localized Kit-PI3K complex is unable to activate Akt. Importantly, M-COPA but not imatinib suppresses neoplastic mast cell proliferation through inhibiting anti-apoptotic Akt activation. Results of our M-COPA treatment assay show that Kit can activate Erk not only on the ER but also on other compartments. Furthermore, Tyr568/570, Tyr703, Tyr721, and Tyr936 in Kit are phosphorylated on the ER, indicating that these five tyrosine residues are all phosphorylated before mutant Kit reaches the plasma membrane (PM). Our study provides evidence that Kit is tyrosine-phosphorylated soon after synthesis on the ER but is unable to activate Akt and also demonstrates that M-COPA is efficacious for growth suppression of neoplastic mast cells.
Journal Article
Requirement of interleukin 7 signaling for anti-tumor immune response under lymphopenic conditions in a murine lung carcinoma model
2016
Induction of lymphopenia before adoptive transfer of T cells was followed by lymphopenia-induced proliferation (LIP) and generated a potent anti-tumor immune response in rodents and in a clinical setting. Previously, we reported that CD28 signaling is essential for the differentiation of functional effector cytotoxic T lymphocytes (CTLs) under lymphopenic conditions and sequential LIP of T cells. In this study, to clarify the correlation between LIP and the anti-tumor effect, LIP was inhibited with interleukin 7 (IL7) receptor blockade at various stages, and the anti-tumor effect then assessed. We confirmed that IL7 signaling at the start of LIP is crucial for the anti-tumor immune response. In contrast, continuous IL7 signaling was not required for tumor regression, although LIP of naïve CD8
+
T cells is usually regulated by IL7. The expansion and migration of CTLs in lymphopenic hosts depend on IL7 signaling during the induction phase. Here, we propose that IL7 signaling and subsequent LIP of T cells have distinct roles in the induction of T cell immunity during lymphopenia.
Journal Article
Astaxanthin-, β-Carotene-, and Resveratrol-Rich Foods Support Resistance Training-Induced Adaptation
2021
Resistance training adaptively increases the muscle strength associated with protein anabolism. Previously, we showed that the combined intake of astaxanthin, β-carotene, and resveratrol can accelerate protein anabolism in the skeletal muscle of mice. The purpose of this study was to investigate the effect of anabolic nutrient-rich foods on muscle adaptation induced by resistance training. Twenty-six healthy men were divided into control and intervention groups. All participants underwent a resistance training program twice a week for 10 weeks. Astaxanthin-, β-carotene-, and resveratrol-rich foods were provided to the intervention group. Body composition, nutrient intake, maximal voluntary contraction of leg extension, oxygen consumption, and serum carbonylated protein level were measured before and after training. The skeletal muscle mass was higher after training than before training in both groups (p < 0.05). Maximal voluntary contraction was increased after training in the intervention group (p < 0.05), but not significantly increased in the control group. Resting oxygen consumption was higher after training in the intervention group only (p < 0.05). As an oxidative stress marker, serum carbonylated protein level tended to be lower immediately after exercise than before exercise in the intervention group only (p = 0.056). Intake of astaxanthin-, β-carotene-, and resveratrol-rich foods supported resistance training-induced strength and metabolic adaptations.
Journal Article