45 research outputs found
肝癌に対する経動脈的治療におけるマイクロカテーテル挿入可能ポー トの開発
PURPOSE: To develop an implantable port in which a microcatheter can be inserted for a combination therapy of repeated transarterial chemoembolization (TACE) and hepatic arterial infusion chemotherapy (HAIC) for advanced liver cancer. MATERIALS AND METHODS: The design of a currently used implantable port was modified. A funnel part was constructed in the port. The septum was punctured by a 20-gauge indwelling needle, and 2.0-Fr non-tapered microcatheter was inserted into the port. In the in vitro studies, the advance of a microcatheter out of the funnel part was evaluated via seven different septum puncture sites. A 5-Fr indwelling catheter connected to the port was placed in a vascular model, and a microcatheter catheterization was evaluated. In an in vivo study, the port-catheter system was implanted in the hepatic artery in a pig. A microcatheter was percutaneously inserted through the port into the hepatic arterial branches, and embolization was performed. RESULTS: In the in vitro studies, the microcatheter was smoothly advanced out of the port and catheterizations into the hepatic arteries were successful via all septum puncture sites. In the in vivo study, repeated selective embolization through the port was successfully conducted on 7, 14 and 21 days after the implantation. CONCLUSION: The developed implantable port can be used for repeated catheter insertion into the hepatic artery. The combination of repeated TACE and HAIC could be possible using this device.博士(医学)・甲第710号・令和元年6月26日© Springer Science+Business Media, LLC, part of Springer Nature and the Cardiovascular and Interventional Radiological Society of Europe (CIRSE) 2018This is a post-peer-review, pre-copyedit version of an article published in Cardiovascular and interventional radiology. The final authenticated version is available online at: http://dx.doi.org/10.1007/s00270-018-2111-0
膜乳化デバイスによるエマルションを用いたウサギVX2肝腫瘍モデノレへの肝動脈化学塞栓術における抗腫瘍効果、薬物動態の検討
Purpose: To evaluate the phamacokinetics of epirubicin in conventional transarterial chemoembolization using a developed pumping emulsification device with a microporous glass membrane in VX2 rabbits. Materials and methods: Epirubicin solution (10 mg/mL) was mixed with ethiodized oil (1:2 ratio) using the device or 3-way stopcock. Forty-eight rabbits with VX2 liver tumor implanted 2 weeks prior to transarterial chemoembolization were divided into 2 groups: a device group (n = 24) and a 3-way-stopcock group (n = 24). Next, 0.5 mL of emulsion was injected into the hepatic artery, followed by embolization using 100-300-μm microspheres. The serum epirubicin concentrations (immediately after, 5 minutes after, and 10 minutes after) and the tumor epirubicin concentrations (20 minutes after and 48 hours after) were measured after transarterial chemoembolization. Histopathologic evaluation was performed with a fluorescence microscope. Results: The area under the curve and maximum concentrations of epirubicin in plasma were 0.45 ± 0.18 μg min/mL and 0.13 ± 0.06 μg/mL, respectively, in the device group and 0.71 ± 0.45 μg min/mL and 0.22 ± 0.17 μg/mL, respectively, in the 3-way-stopcock group (P = .013 and P = .021, respectively). The mean epirubicin concentrations in VX2 tumors at 48 hours in the device group and the 3-way-stopcock group were 13.7 ± 6.71 and 7.72 ± 3.26 μg/g tissue, respectively (P = .013). The tumor necrosis ratios at 48 hours were 62 ± 11% in the device group and 51 ± 13% in the 3-way-stopcock group (P = .039). Conclusions: Conventional transarterial chemoembolization using the pumping emulsification device significantly improved the pharmacokinetics of epirubicin compared to the current standard technique using a 3-way stopcock.博士(医学)・乙第1443号・令和元年12月5日Copyright © 2019 SIR. Published by Elsevier Inc. All rights reserved
ラット肝腫瘍モデルにおける化学療法の早期効果判定に有用なダイナミック造影超音波のパラメータについて
Objectives: The objective of the study is to determine a parameter on the time-intensity curve (TIC) of dynamic
contrast-enhanced ultrasonography (DCE-US) that best correlates with tumor growth and to evaluate whether
the parameter could correlate with the early response to irinotecan in a rat liver tumor model.
Material and Methods: Twenty rats with tumors were evaluated (control: Saline, n = 6; treatment: Irinotecan,
n = 14) regarding four parameters from TIC: Peak intensity (PI), k value, slope (PI × k), and time to peak (TTP).
Relative changes in maximum tumor diameter between day 0 and 10, and parameters in the first 3 days were
evaluated. The Mann-Whitney U-test was used to compare differences in tumor size and other parameters.
Pearson’s correlation coefficients (r) between tumor size and parameters in the control group were calculated.
In the treatment group, relative changes of parameters in the first 3 days were compared between responder and
non-responder (<20% and ≥20% increase in size on day 10, respectively).
Results: PI, k value, PI × k, and TTP significantly correlated with tumor growth (r = 0.513, 0.911, 0.665, and 0.741,
respectively). The mean RC in k value among responders (n = 6) was significantly lower than non-responders
(n = 8) (mean k value, 4.96 vs. 72.5; P = 0.003).
Conclusion: Parameters of DCE-US could be a useful parameter for identifying early response to irinotecan.博士(医学)・甲第879号・令和5年3月15
犬モデルにおける ex vivo および in vivo 遺伝子治療のための代替遺伝子導入技術の開発
Introduction: Gene therapy have recently attracted much attention as a curative therapeutic option for inherited single gene disorders such as hemophilia. Hemophilia is a hereditary bleeding disorder caused by the deficiency of clotting activity of factor VIII (FVIII) or factor IX (FIX), and gene therapy for hemophilia using viral vector have been vigorously investigated worldwide. Toward further advancement of gene therapy for hemophilia, we have previously developed and validated the efficacy of novel two types of gene transfer technologies using a mouse model of hemophilia A. Here we investigated the efficacy and safety of the technologies in canine model. Especially, validations of technical procedures of the gene transfers for dogs were focused. Methods: Green fluorescence protein (GFP) gene were transduced into normal beagle dogs by ex vivo and in vivo gene transfer techniques. For ex vivo gene transfer, blood outgrowth endothelial cells (BOECs) derived from peripheral blood of normal dogs were transduced with GFP gene using lentivirus vector, propagated, fabricated as cell sheets, then implanted onto the omentum of the same dogs. For in vivo gene transfer, normal dogs were subjected to GFP gene transduction with non-viral piggyBac vector by liver-targeted hydrodynamic injections. Results: No major adverse events were observed during the gene transfers in both gene transfer systems. As for ex vivo gene transfer, histological findings from the omental biopsy performed 4 weeks after implantation revealed the tube formation by implanted GFP-positive BOECs in the sub-adipose tissue layer without any inflammatory findings, and the detected GFP signals were maintained over 6 months. Regarding in vivo gene transfer, analyses of liver biopsy samples revealed more than 90% of liver cells were positive for GFP signals in the injected liver lobes 1 week after gene transfers, then the signals gradually declined overtime. Conclusions: Two types of gene transfer techniques were successfully applied to a canine model, and the transduced gene expressions persisted for a long term. Toward clinical application for hemophilia patients, practical assessments of therapeutic efficacy of these techniques will need to be performed using a dog model of hemophilia and FVIII (or FIX) gene.博士(医学)・乙第1517号・令和3年12月21日© 2021, The Japanese Society for Regenerative Medicine. Production and hosting by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/
4.0/)
ラット凍結肩モデルを用いた経カテーテル的動脈塞栓術の効果に関する検討
Purpose: To assess the angiographic findings and the effects of transcatheter arterial embolization on physical activity and histopathology using a frozen shoulder rat model. Materials and methods: First, the angiographic and histopathologic findings of rats in which the shoulder was immobilized with molding plaster for 6 weeks (n = 4) were compared to control rats with normal non-immobilized shoulders (n = 4). Next, a total of 16 frozen shoulder rats were divided into 2 groups. In the transcatheter arterial embolization group (n = 8), imipenem/cilastatin was injected into the left thoracoacromial artery. The changes of physical activity before and after procedures were evaluated and compared with a saline-injected control group (n = 8). Histopathologic findings were also compared between the 2 groups. Results: Angiography revealed abnormal shoulder staining in all of the rats with a frozen shoulder. On histopathology, the numbers of microvessels and mononuclear inflammatory cells in the synovial membrane of the joint capsule were significantly higher compared with the control rats (both P = .03). In the transcatheter arterial embolization group, the running distance and speed were improved (P = .03 and P = .01, respectively), whereas there were no significant differences in the control group. The number of microvessels and mononuclear inflammatory cells in the transcatheter arterial embolization group were significantly lower than the control group (P = .002 and P = .001, respectively). Conclusions: The rat frozen shoulder model revealed the development of neovascularization. Transcatheter arterial embolization decreased the number of blood vessels and inflammatory changes in the frozen shoulder and increased the moving distance and speed of the rats.博士(医学)・甲第789号・令和3年3月15日Copyright © 2020 SIR(Society of Interventional Radiology). Published by Elsevier Inc. All rights reserved
超吸水性ポリマー球状塞栓物質の高張食塩水を用いた膨潤抑制法の開発
PURPOSE: To analyze size changes of superabsorbent polymer (SAP) microspheres with the reduced expansion technique, and to evaluate pharmacological advantages of transarterial chemoembolization using cisplatin-loaded SAP microspheres with the reduced expansion technique. MATERIALS AND METHODS: In an in vitro study, diluted contrast materials containing different concentrations of sodium ions were examined to expand SAP microspheres and determined the reduced expansion technique. Size distributions of cisplatin-loaded SAP microspheres were analyzed. In an in vivo study, TACE was performed using cisplatin-loaded SAP microspheres with the reduced expansion and control techniques in 18 VX2 rabbits. RESULTS: The degree of expansion was reduced to the greatest extent by using a mixture of non-ionic contrast material and 10% NaCl at a 4:1 ratio. The mean diameter of the reduced expansion of cisplatin-loaded SAP microspheres was 188.4 μm, while that of the control expansion was 404.9 μm. The plasma platinum concentrations of the reduced expansion group at 5 min after TACE were significantly higher than those of the control expansion group (2.19 ± 0.77 vs. 0.75 ± 0.08 μg/mL, P = .01). The tumor platinum concentrations of the reduced expansion group at 1 h were significantly higher than those of the control expansion group (10.76 ± 2.57 vs. 1.57 ± 0.14 μg/g, P = .044). CONCLUSION: The expanding level of SAP microspheres can be reduced by using hypertonic saline. Cisplatin-loaded SAP microspheres with the reduced expansion technique have the advantages of achieving higher cisplatin tissue concentration in TACE for liver tumors.博士(医学)・甲第709号・令和元年6月26日© Springer Science+Business Media, LLC, part of Springer Nature and the Cardiovascular and Interventional Radiological Society of Europe (CIRSE) 2018This is a post-peer-review, pre-copyedit version of an article published in Cardiovascular and interventional radiology. The final authenticated version is available online at: http://dx.doi.org/10.1007/s00270-018-1990-4
Pace running of a quadruped robot driven by pneumatic muscle actuators : An experimental study
Our goal is to design a neuromorphic locomotion controller for a prospective bioinspired quadruped robot driven by artificial muscle actuators. In this paper, we focus on achieving a running gait called a pace, in which the ipsilateral pairs of legs move in phase, while the two pairs together move out of phase, by a quadruped robot with realistic legs driven by pneumatic muscle actuators. The robot is controlled by weakly coupled two-level central pattern generators to generate a pace gait with leg loading feedback. Each leg is moved through four sequential phases like an animal, i.e., touch-down, stance, lift-off, and swing phases. We find that leg loading feedback to the central pattern generator can contribute to stabilizing pace running with an appropriate cycle autonomously determined by synchronizing each leg’s oscillation with the roll body oscillation without a human specifying the cycle. The experimental results conclude that our proposed neuromorphic controller is beneficial for achieving pace running by a muscle-driven quadruped robot
A case report of pulmonary amyloidosis recognized by detection of AA amyloid exclusively in alveolar macrophages
Amyloidosis is a rare condition in which tissue deposits of inert fibrillar protein result in organ damage and dysfunction. There are several types of amyloid fibrils. Some of the most common forms are AL (amyloid light chain) protein and AA (amyloid-associated) type of amyloid fibril protein. Pulmonary amyloidosis is relatively common but is usually asymptomatic. Thus, the diagnosis may be easily overlooked. A 78-year-old male with a history of multiple myeloma followed by systemic amyloidosis presented with abnormal chest CT showing diffuse interlobular thickening in the whole lung field with bilateral pleural effusion. Bronchoalveolar lavage and transbronchial biopsy were performed. Due to the patient’s poor condition and hemorrhage, only one fragment was available from forceps biopsy. Histologically, there was no amyloid deposition in the lung parenchyma;however, some histiocytes showed eosinophilic granular contents which prompted us to perform additional staining. The cytoplasmic material turned to be positive with direct fast scarlet (DFS) staining and AA amyloid immunostaining. Similar macrophages with AA amyloid were also found in the bronchoalveolar fluid. We experienced a case with AA amyloidosis affecting the lung diagnosed by the presence of intracytoplasmic amyloid in alveolar macrophages. The microscopic changes were so subtle that they may be overlooked. Recognition of amyloid deposition in alveolar macrophages may be an important clue to diagnose pulmonary amyloidosis. Such finding is of particular significance in the small-sized specimens, such as biopsies and cytologic smears