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Yamakami Y, Kimura S, Hara K, Ohmori M, Tateishi R, Kaneda T, Shimada H, Manno T, Isshiki A, Shimizu M, Fujii H, Suzuki M, Sasano T. The comparison of the chronic-phase vascular healing between bioabsorbable and durable polymer drug eluting stent by using optical coherence tomography. Eur Heart J 2020. [DOI: 10.1093/ehjci/ehaa946.2472] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Abstract
Background
Bioabsorbable polymer drug eluting stents (BP-DESs) were designed to reduce a vascular inflammatory reaction compared to durable polymer drug eluting stents (DP-DESs). However, few studies have compared vascular responses to BP-DESs and DP-DESs.
Methods
We enrolled 88 consecutive patients with single culprit coronary artery lesions (31 lesions with acute coronary syndrome) undergoing a single stent-implantation. BP-DESs and DP-DESs were implanted in 50 (57%) and 38 patients (43%), respectively. All lesions underwent optical coherence tomography examination at chronic phase and intrastent OCT findings at the follow-up were evaluated in every 1-mm cross-sections (CSs).
Results
A total of 1887 CSs (BP-DES: 1096, DP-DES: 791) were analyzed. The median period of follow-up OCT was 293 (250–374) days. There were no differences in the patient, lesion, and initial clinical presentation of acute coronary syndrome (ACS). BP-DESs had significantly higher percent neointimal hyperplasia area, defined as neointimal hyperplasia area divided by stent area x 100 (18.4±9.0% vs. 16.1±9.9%, p<0.001), fewer malapposed struts (1.7% vs. 3.9%, p=0.005), fewer uncovered struts (3.6% vs. 5.8%, p=0.02) but higher frequency of superficial low intensity neointima (LIN) (7.7% vs. 3.4%, p<0.001). Multivariate logistic analysis showed that BP-DES (OR: 2.5, 95% CI: 1.49–4.08, p<0.001) and the initial clinical presentation of ACS (OR: 2.31, 95% CI: 1.47–3.62, p<0.001) are independent predictive factors for LIN.
Conclusion
BP-DESs showed homogenous neointimal growth and complete stent coverage quantitatively. Meanwhile, the significant relationships of BP-DES with LIN may suggest that the neointimal quality remains immature in BP-DESs in this period.
Funding Acknowledgement
Type of funding source: None
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Kimura S, Hara K, Ohmori M, Tateishi R, Kaneda T, Yamakami Y, Shimada H, Manno T, Iishiki A, Shimizu M, Fujii H, Suzuki M, Sasano T. Optical coherence tomography findings in healed vulnerable plaques in patients with coronary artery disease. Eur Heart J 2020. [DOI: 10.1093/ehjci/ehaa946.2461] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Abstract
Background
Histopathological analysis or intracoronary image assessment of healed plaques (HPs) has been reported both in acute coronary syndrome (ACS) and stable angina pectoris (SAP) patients. However, background characteristics or lesion morphologies of HPs could not be fully clarified and their differences according to the clinical status remain undetermined.
Purpose
We sought to investigate the clinical and morphological characteristics and compare their differences among ACS and SAP patients in order to clarify the clinical significance in HPs lesions.
Methods
We enrolled consecutive 201 patients with 213 native coronary artery lesions (139 lesions with SAP, 42 ST elevation-ACS (STE-ACS) and 32 non-ST elevation ACS (NSTE-ACS) undergoing pre-intervention optical coherence tomography (OCT). HPs was defined as layered phenotype on OCT. Clinical and angiography characteristics and lesion morphologies on OCT were assessed.
Results
HPs were observed in 110 lesions (51.6%) and their prevalence were not different according to the clinical status (SAP:55.1%, STE-ACS:38.1%, NSTE-ACS:56.3%, p=0.14). Lesions with HPs had higher frequencies of angiography-eccentric lesions (62.7% vs. 35.9%, p<0.001) and OCT-macrophages (65.5% vs. 43.1%, p<0.001), and greater OCT-lumen area stenosis (%-AS) (77.1±10.2% vs. 73.6±10.6%, p=0.01) than those without HPs. Of lesions with HPs, OCT-thin-cap fibroatheroma (SAP 14.4%, STE-AC43.8%, NSTE-ACS 16.7%, p=0.03), plaque rupture (5.3%; 37.5%; 11.1%, p<0.001) and thrombus (6.6%, 75.0%, 22.2%, p=0.007) were more frequently observed in STE-ACS than in SAP patients, whereas OCT-microvessels were more frequent in SAP than in ACS patients (19.7%, 0.0%, 0.0%, p=0.02). Other OCT findings such as macrophages, cholesterol crystal, multiple layered phenotype, and %-AS were not significantly different according to the clinical status. Multivariate logistic regression analysis identified the angiography-eccentric lesions (odds ratio (OR): 2.97, 95% confidence intervals (CI): 1.68–5.25, p<0.001) and OCT macrophages (OR 2.41, 95% CI 1.36–4.27, p=0.003) as independent related factors for the existence of HPs.
Conclusions
The present study showed that HPs lesions had eccentric and large plaque burden, and persistent plaque inflammations regardless of clinical status, which might lead to future coronary events.
Funding Acknowledgement
Type of funding source: None
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Kimura S, Hara K, Ohmori M, Tateishi R, Kaneda T, Yamakami Y, Shimada H, Manno T, Iishiki A, Shimizu M, Fujii H, Suzuki M, Sasano T. Optical coherence tomography and coronary angioscopy assessment of healed vulnerable plaque components in patients with coronary artery lesions undergoing elective percutaneous coronary intervention. Eur Heart J 2020. [DOI: 10.1093/ehjci/ehaa946.2444] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Abstract
Background
Many vulnerable plaques would progress without clinical events and might result in healed plaques (HPs). Histopathological or intracoronary image assessment of HPs has been reported. However, the morphological characteristics of HPs remain unclear yet.
Purpose
We sought to assess the healed vulnerable plaque components in patients with coronary artery lesions using optical coherence tomography (OCT) and coronary angioscopy (CAS).
Methods
We enrolled 47 patients with 50 native coronary artery lesions with angiographical severe stenosis (>90% diameter-stenosis) and without severe calcification (36 lesions with stable angina pectoris (SAP) and 14 acute coronary syndrome (ACS)) undergoing pre-intervention OCT and CAS. HPs was defined as layered phenotype on OCT. Lesion morphologies and plaque characteristics in lesions with HPs were assessed using OCT and CAS images.
Results
HPs were observed in 27 lesions (54.0%) and their prevalence were similar among each clinical status (SAP 52.8%, ACS 57.1%, p=1.00). Lesions with HPs had higher prevalence of OCT-macrophage (88.0% vs. 52.0%, p=0.01), CAS-red thrombus (88.8% vs. 52.2%, p=0.004) and CAS-low grade-yellow plaque (grade 1) (55.6% vs. 21.7%, p=0.02) than those without. SAP lesions with HPs had higher prevalence of CAS-yellow plaque (35.3% vs. 5.9%, p=0.09) and OCT-thin-cap fibroatheroma (42.1% vs. 5.9%, p=0.04) than SAP without HPs. ACS lesions with HPs had less CAS-red thrombus (0.0% vs. 50.0%, p=0.03) and OCT-plaque rupture (12.5% vs. 66.7%, p=0.04) than ACS without HPs. Multivariate logistic regression analysis revealed that OCT-macrophages (odds ratio (OR): 6.65, 95%-confidence intervals: 1.07–41.5, p=0.043), CAS-red thrombus (OR 8.77, 95% CI 1.33–57.8, p=0.02), and low grade-yellow plaque (OR 13.05, 95% CI 1.97–86.5, p=0.008) were independently related with the existence of HPs lesions. Combination of these 3 factors showed a high predictive value of OCT-HPs lesions (90.9%).
Conclusions
HPs lesions showed the lower lesion vulnerability than common ACS lesions but had more intraplaque inflammatory condition compared with common SAP lesions. Combined CAS and OCT examination might be useful to clarify the plaque components of HPs lesions in vivo, leading to help us understand the clinical significance of HPs.
Funding Acknowledgement
Type of funding source: None
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Shimizu M, Cho S, Hara K, Ohmori M, Kaneda T, Tateishi R, Yamakami Y, Shimada H, Manno T, Isshiki A, Kimura S, Fujii H, Suzuki M, Nishizaki M, Sasano T. Differences of ST level at J-point on 12-lead electrocardiography can distinguish takotsubo syndrome and acute anterior myocardial infarction. Eur Heart J 2020. [DOI: 10.1093/ehjci/ehaa946.2152] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Abstract
Background
Qualitative difference of ST elevation/depression on 12-leads electrocardiography (ECG) at onset was reported in patients with Takotsubo syndrome (TTS) and acute anterior myocardial infarction (ant AMI). However, quantitative difference of those was not elucidated.
Purpose
To investigate differences of ST level at J point on ECG between TTS and ant AMI by automated calculating system.
Methods
We firstly enrolled consecutive 40 patients of TTS, and among 500 ant AMI patients, one to two random matching was done by their age and gender. Finally, 40+80 patients (74.5±11.2 years, 87 females) were enrolled. ECG at onset of both group was measured by automated system (ECAPs12c: Nihon-Koden).
Results
ST level of TTS at J-point in I/II/V4–6 lead was significantly elevated comparing to that of ant AMI. Conversely, Conversely, significant ST depression in aVR and no ST elevation in V1 of TTS was observed in TTS. Logistic regression analysis revealed that ST elevation in I lead and no ST elevation in V1 lead showed high odds ratio and low P value.
Conclusion
Automated measured ST level at J-point was a powerful tool to distinguish TTS and ant AMI at onset.
Funding Acknowledgement
Type of funding source: None
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Shimizu M, Cho S, Hara K, Ohmori M, Kaneda T, Tateishi R, Yamakami Y, Shimada H, Manno T, Isshiki A, Kimura S, Fujii H, Suzuki M, Nishizaki M, Sasano T. Diagnostic performance of 18-leads electrocardiography to distinguish takotsubo syndrome and acute anterior myocardial infarction. Eur Heart J 2020. [DOI: 10.1093/ehjci/ehaa946.3445] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Abstract
Background
Electrocardiographic (ECG) features on acute phase of Takotsubo syndrome (TTS) is recognized to mimic that of acute anterior myocardial infarction (ant AMI). However, the difference of synthesized 18-leads ECG of both diseases was not elucidated.
Purpose
To elucidate diagnostic performance of 18-leads ECG to distinguish TTS and acute anterior AMI.
Methods
We firstly enrolled consecutive 40 patients of TTS, and among 500 ant AMI patients, one to two matching was done by their age and gender. Finally, 40+80 patients (74.5±11.2 years, 87 females) were enrolled, and ECG at onset of both group was estimated. Because of multicollinearity, all significant differences were compared by machine learning (Random Forest method).
Results
Prevalence of Q wave had no difference. Conversely, ST depression in TTS and ST elevation in ant AMI were significant differences in V7–9 leads. T-wave polarity of V3R-V9 leads were significantly different (flat T-wave in TTS and positive in ant AMI). Machine learning revealed T wave polarity in V7 lead had the highest feature importance.
Conclusion
18-leads ECG at onset had powerful diagnostic performance to distinguish the two diseases.
Funding Acknowledgement
Type of funding source: None
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Kimura S, Suzuki R, Machida K, Nishihama R, Okui M, Nakamura T. Proposal of Motion Judgment Algorithm Based on Joint Angle of Variable Elastic Assist Suit with High Back Drivability. JOURNAL OF ROBOTICS AND MECHATRONICS 2020. [DOI: 10.20965/jrm.2020.p0863] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
In recent years, the burden per worker has increased due to a decrease in the working population. Wearable assist suits have been developed as one of the methods for solving the problem. To extend the assist suit to practical situations, it is necessary to provide a motion judgment interface for judging the motion of a wearer. Therefore, in our study, a motion judgment algorithm is proposed for assist suits, based on variable viscoelasticity. The proposed algorithm judges sitting, standing-up, stance, sitting-down, and gait using only the joint angle information of the suit and verification is performed using human joint angles obtained by motion capture. Thus, the motion judgment rate is 90% or more for sitting, standing-up, stance, and sitting-down, and 80% or more for gait, confirming the usefulness of motion judgment. Additionally, based on these results, further verification is performed on an actual machine. As a result, in a series of motions starting from the sitting to the standing-up, the stance, and the gait, the motion judgement is successful five times from the sitting to the standing-up, the stance, and once in gait. In a series of motions from sitting to standing-up, the stance, and sitting-down, the motion judgment is successful five times during sitting; five times during sitting, stance, and sitting-down; and three times during standing-up. In this way, it is confirmed that the proposed method can judge the motion only by angle information, although there is a problem in a success rate depending on the motion.
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Livesey LC, Yorke E, Parra A, Gray Q, Davies C, Weldon D, Schumacher J, Kimura S, Howard C, Sierra‐Rodriguez T, Mora‐Pereira M. Use of a carbonated beverage to disintegrate a phytobezoar obstructing the intrathoracic portion of the oesophagus of a horse. EQUINE VET EDUC 2020. [DOI: 10.1111/eve.13082] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Mori K, Kimura S, Egawa S, Shahrokh S. Prognostic value of preoperative De Ritis ratio in upper tract urothelial carcinoma treated with radical nephroureterectomy. EUR UROL SUPPL 2020. [DOI: 10.1016/s2666-1683(20)34095-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022] Open
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59
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Janisch F, D’Andrea D, Iwata T, Kimura S, Abufaraj M, Enikeev D, Glybochko P, Karakiewicz P, Nyiradi P, Fajokvic H, Haitel A, Seebacher V, Rink M, Shariat S. The clinical value of the urokinase-plasminogen activator system (uPA) in patients with radical cystectomy (RC) for bladder cancer. EUR UROL SUPPL 2020. [DOI: 10.1016/s2666-1683(20)33620-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
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60
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Kimura S, Yagi R, Nakase K, Ogawa D, Manno T, Yamada K, Taniguchi H, Wanibuchi M. Rupture of a Left Posterior Inferior Cerebellar Artery Aneurysm with a Vertebral Artery Originating from the Aorta. JOURNAL OF NEUROENDOVASCULAR THERAPY 2020; 14:279-284. [PMID: 37502619 PMCID: PMC10370520 DOI: 10.5797/jnet.cr.2019-0105] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/12/2019] [Accepted: 03/31/2020] [Indexed: 07/29/2023]
Abstract
Objective Cerebral aneurysms (ANs) in the cortical segment (CS) of the distal posterior inferior cerebellar artery (PICA) with a vertebral artery (VA) of aortic origin are markedly rare. Endovascular therapy was performed to treat subarachnoid hemorrhage caused by a ruptured cerebral AN. Case Presentation The patient was a 68-year-old female who was transported to emergency care for headache. Detailed examination revealed an AN in the CS of the PICA with a left VA of distal aortic origin from the left subclavian artery (LT. SA). Endovascular therapy using n-butyl-2-cyanoacrylate (NBCA) was performed to treat the cerebral AN, resulting in a favorable outcome. Conclusion Endovascular therapy for cerebral ANs is an effective treatment method.
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Miura S, Fukushima M, Kurosawa H, Kimura S. Epidemiology of long-stay patients in the pediatric intensive care unit: prevalence, characteristics, resource consumption and complications. JOURNAL OF PUBLIC HEALTH-HEIDELBERG 2020; 30:111-119. [PMID: 32421088 PMCID: PMC7223791 DOI: 10.1007/s10389-020-01282-3] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/02/2019] [Accepted: 04/01/2020] [Indexed: 11/03/2022]
Abstract
Background The impact of pediatric intensive care unit (PICU) utilization and resource consumption among long-stay patients has not been characterized recently. This study aimed to describe the resource consumption and characteristics of long-stay patients in a PICU. Methods This was a single-center descriptive cohort study of 1309 patients admitted to a PICU in 2017. The main outcome was ICU length of stay (LOS). Patients were divided into prolonged LOS (PLS) and non-PLS groups if they had an LOS of ≥ 28 or < 28 days, respectively. Two groups were compared to characterize PLS. Results Thirty-two (2.4%) patients had a PLS and utilized 33% of PICU bed days. Factors associated with PLS with odds ratio [95% confidence interval (CI)] were being a neonate (7.8 [2.5-25.4], p = <0.001), being an infant (2.9 [1.0-9.0], p = 0.04), admission for a respiratory ailment (7.3 [1.6-44.2], p = 0.003), cardiovascular dysfunction (24.1 [4.8-152.1], p = <0.001), post-cardiac operation (8.0 [1.7-50.1], p = 0.003), post-cardiopulmonary arrest (22.8 [1.7-211.9], p = 0.01), and transfer from another facility (4.2 [1.8-10.7], p = 0.001). PLS patients developed more nosocomial infections and disproportionately received monitoring and therapeutic resources. Conclusions A PLS was associated with substantial PICU utilization and complication rates. Future studies should aim to alleviate both institutional and patient-related issues in the affected population harboring possible risk factors for PLS.
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Kidoguchi K, Kubota Y, Kusaba K, Kizuka-Sano H, Yamaguchi K, Nishioka A, Yokoo M, Ando T, Kojima K, Kimura S. Severe infusion reaction, anti-rituximab antibodies and lymphoma. QJM 2020; 113:273-274. [PMID: 31702763 DOI: 10.1093/qjmed/hcz296] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/29/2019] [Revised: 10/29/2019] [Indexed: 11/14/2022] Open
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Arakawa M, Saiki T, Wada K, Ogawa K, Kadono T, Shirai K, Sawada H, Ishibashi K, Honda R, Sakatani N, Iijima Y, Okamoto C, Yano H, Takagi Y, Hayakawa M, Michel P, Jutzi M, Shimaki Y, Kimura S, Mimasu Y, Toda T, Imamura H, Nakazawa S, Hayakawa H, Sugita S, Morota T, Kameda S, Tatsumi E, Cho Y, Yoshioka K, Yokota Y, Matsuoka M, Yamada M, Kouyama T, Honda C, Tsuda Y, Watanabe S, Yoshikawa M, Tanaka S, Terui F, Kikuchi S, Yamaguchi T, Ogawa N, Ono G, Yoshikawa K, Takahashi T, Takei Y, Fujii A, Takeuchi H, Yamamoto Y, Okada T, Hirose C, Hosoda S, Mori O, Shimada T, Soldini S, Tsukizaki R, Iwata T, Ozaki M, Abe M, Namiki N, Kitazato K, Tachibana S, Ikeda H, Hirata N, Hirata N, Noguchi R, Miura A. An artificial impact on the asteroid (162173) Ryugu formed a crater in the gravity-dominated regime. Science 2020; 368:67-71. [PMID: 32193363 DOI: 10.1126/science.aaz1701] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2019] [Accepted: 03/04/2020] [Indexed: 11/02/2022]
Abstract
The Hayabusa2 spacecraft investigated the small asteroid Ryugu, which has a rubble-pile structure. We describe an impact experiment on Ryugu using Hayabusa2's Small Carry-on Impactor. The impact produced an artificial crater with a diameter >10 meters, which has a semicircular shape, an elevated rim, and a central pit. Images of the impact and resulting ejecta were recorded by the Deployable CAMera 3 for >8 minutes, showing the growth of an ejecta curtain (the outer edge of the ejecta) and deposition of ejecta onto the surface. The ejecta curtain was asymmetric and heterogeneous and it never fully detached from the surface. The crater formed in the gravity-dominated regime; in other words, crater growth was limited by gravity not surface strength. We discuss implications for Ryugu's surface age.
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ITOU Y, Kimura S, Fujiwara Y, Yamamoto Y, Okamura S, Okawa T, Murakami M, Matsuo K, Tanaka S, Mori N, Mori K. SUN-415 THROMBOTIC MICROANGIOPATHY AFTER STEROID PULSE THERAPY IN A RAPIDLY-PROGRESSIVE GLOMERULONEPHRITIS CASE HAVING HIGH -TITER ANTI-GBM ANTIBODY AND MPO-ANCA. Kidney Int Rep 2020. [DOI: 10.1016/j.ekir.2020.02.955] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022] Open
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Kashima M, Arakawa H, Kimura S, Nishihama R, Yokoyama K, Kikutani I, Nakamura T. Development of Assist Suit for Squat Lifting Support Considering Gait and Quantitative Evaluation by Three-Dimensional Motion Analysis. JOURNAL OF ROBOTICS AND MECHATRONICS 2020. [DOI: 10.20965/jrm.2020.p0209] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Globally, lower back pain is a serious problem. For workers, it not only causes health problems but also has social and economic influences. Lower back pain could be attributed to burden on people’s waists when they handle heavy objects. Ministry of Health, Labour and Welfare in Japan recommends squat lifting, a method of lifting objects with a smaller burden on waist. On the other hand, squat lifting is not commonly used because it requires deep bending of knees to lift an object, leading to a larger work load. Therefore, a leaf-spring type power assist suit for legs has been developed in order to assist squat lifting. However, if the fixing performance of a preceding machine was enhanced, a leaf spring could impede the bending of knee joints during gait motion. In the present study, we developed a power assist suit for legs using a slide mechanism. A leaf spring was chosen so as to meet a target assist torque determined by a motion analysis for lifting objects. In addition, we made a prototype machine with slide mechanism. EMG measurement of the thigh muscle during lifting actions using the prototype machine showed a decrease of up to 46%. It was also confirmed that a machine with slide mechanism could realize a more natural gait than a machine without it.
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Cruijsen H, Poitevin E, Brunelle SL, Almeida S, Braun U, Connelly M, Giuliani L, Huertas R, Hui S, Ikeuchi Y, Jaudzems G, Kimura S, Kittleson J, Larkin G, Li F, McMahon A, Nagatoshi M, Piccon I, Postma M, Rizzo A, Sadipiralla B, Shan L, Shinichi T, Silva F, Torres M, van Goethem S, vander Moolen H, Xindong G. Determination of Minerals and Trace Elements in Milk, Milk Products, Infant Formula, and Adult Nutrition: Collaborative Study 2011.14 Method Modification. J AOAC Int 2019. [DOI: 10.1093/jaoac/102.6.1845] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Abstract
Official Method SM 2011.14/ISO 15151:2018/IDF 229:2018 uses microwave digestion of samples and inductively coupled plasma–atomic emission spectrometry for determination of nine elements, including Ca, Cu, Fe, K, Mg, Mn, Na, P, and Zn. The method was evaluated in a collaborative study of 25 products, including 13 fortified nutritional products (powders, ready-to-feed liquids, and liquid concentrates), five product placebos, six dairy products (liquids, powders, butter, and processed cheese), and the National Institute for Standards and Technology (NIST) Standard Reference Material (SRM) 1849a, in compliance with AOAC INTERNATIONAL Standard Method Performance Requirement (SMPR®) 2014.004. This study significantly expanded the applicability of Official Method 2011.14 beyond the original scope of chocolate milk powder, dietetic milk powder, infant cereal, peanut butter, and wheat gluten. The study included 14 collaborators from 11 countries, and results were compared to SMPR 2014.004. Accuracy of the method was demonstrated using NIST SRM 1849a, yielding recoveries across all laboratories of 98–101% for the nine elements. Precision for the 13 fortified nutritional product samples was 2.2–3.9% for repeatability (relative SD of repeatability) and 6.0–12.2% for reproducibility (RSDR). Excluding Mn, which was present at a wide range of concentrations, the reproducibility was 6.0–9.5%, meeting the performance requirements of SMPR 2014.004. Placebo samples (not fortified with Cu, Fe, Mn, or Zn) yielded acceptable repeatability of 1.8–2.9% for Ca, K, Mg, Na, and P (minerals) but 5.4–29.4% for the low levels of Cu, Fe, Mn, and Zn (trace elements). Reproducibility for the placebos showed the same pattern, with acceptable reproducibility (5.4–10.3%) for minerals but not for the low levels of the trace elements (13.2–82.8%). In the six dairy product samples, repeatability ranged from 1.6 to 3.6% for the minerals, Zn, and the low range of Mn but from 9.4 to 24.6% for Cu, Fe, and the high range of Mn, where concentrations were low as for the nutritional placebos. Reproducibility in the dairy samples was 5.3–8.8% for the minerals but 11.4–55.0% for the trace elements. The mean concentrations of Cu, Fe, and Zn in the dairy products were similar with those in the placebo products, while Zn was present at levels more similar with the fortified nutritional products. Thus, the method met the SMPR criteria except where the trace minerals were present at very low levels. Based on these results, the AOAC Stakeholder Panel for Infant Formula and Adult Nutritionals recommended Final Action status of the expanded applicability of the method. The method was adopted as Final Action by the AOAC Official Methods Board.
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Manno T, Shimizu M, Ohomri M, Taomoto Y, Kaneda T, Yamakami Y, Iiya M, Shimada H, Isshiki A, Kimura S, Fujii H, Suzuki M, Hirao K. P4386Prognostic value of pressure-strain curve analysis by echocardiography for cardiac death in patients with congestive heart failure. Eur Heart J 2019. [DOI: 10.1093/eurheartj/ehz745.0791] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Abstract
Background
Pressure-strain curve analysis (PS-curve) is novel method of echocardiographic evaluation for left ventricular (LV) systolic myocardial work including the effect of blood pressure. However, the prognostic value of PS-curve for prospective cardiac death in patients with congestive heart failure (CHF).
Purpose
To elucidate the prognostic value of PS-curve analysis for cardiac death in patients with CHF.
Methods
We enrolled 63 consecutive sinus-rhythm patients with CHF admission who were evaluated by PS-curve analysis before discharge (76.0±13.3 years, 39 males). Endpoint was set as all cardiac death.
Results
Observation period was median 327 days [25%: 91, 75%: 656 days], and the longest period was 1004 days. Five patients died for cardiac causes. Multivariate Cox regression analysis (stepwise regression) revealed diastolic blood pressure (BP) and global constructive work (GCW) were independent predictors (Hazard ratio: 0.854, 0.996, P value: 0.016, 0.019, respectively). ROC curve analysis demonstrated GCW ≤601 had high diagnostic performance for cardiac death (specificity 0.891, sensitivity 0.800, area under ROC 0.824). Kaplan-Meyer curve analysis indicated the group with GCW ≤601 was worse cardiac prognosis (Logrank P<0.001).
Cox Hazard Regression Analysis Univariate Multivariate (stepwise regression) Hazard Ratio 95% CI P Hazard Ratio 95% CI P BP systole (mmHg) 0.915 0.85–0.99 0.026 BP diastole (mmHg) 0.915 0.84–0.99 0.043 0.854 0.75–0.97 0.016 LVDd (mm) 1.064 1.01–1.12 0.025 NA LVDs (mm) 1.066 1.01–1.12 0.016 LVEF (%) 0.963 0.91–1.02 0.221 LAD (mm) 1.197 1.06–1.36 0.005 GWE 0.937 0.88–0.99 0.041 GWI 0.998 0.99–0.99 0.041 NA GCW 0.998 0.99–0.99 0.037 0.996 0.99–0.99 0.019 GWW 0.996 0.98–1.01 0.502 Considering multicollinearity, we excluded GWI and LVDd (correlation coefficient: GWI and GCW = 0.979, LVDd and LVDs = 0.942).
Conclusion
Pressure-strain curve analysis had powerful predictive value for cardiac death in patients with CHF.
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Iiya M, Kimura S, Shimizu M, Fujii H, Suzuki M. P1704The impact of electrocardiographic changes upon resuscitation from out-of-hospital cardiac arrest on mortality. Eur Heart J 2019. [DOI: 10.1093/eurheartj/ehz748.0459] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Abstract
Background
The serial electrocardiographic changes in patients following out-of-hospital cardiac arrest (OHCA) are unclear.
Purpose
To evaluate serial electrocardiographic changes and to predict all-cause mortality in patients following OHCA.
Methods
We retrospectively studied 101 OHCA patients (70±16 years, 49 male) who achieved a return of spontaneous circulation (ROSC) and survived for ≥3hours. Twelve-lead electrocardiograms (ECGs) were evaluated twice in each patient: initial-ECG, after achieving ROSC; and 2nd-ECG, after receiving the initial evaluation in the emergency room. Patients were divided into two groups: S-group, those surviving for 28 days, and D-group, those dying within 28 days. Multivariate Cox regression analyses were performed to predict the 28-day survival following OHCA. A Kaplan-Meier curve analysis for the 28 day mortality stratified by the QRS morphology and rhythm of initial-ECG was performed.
Results
Among variables of initial-ECG, there were significant differences between the group-S and group-D (table). Multivariate analysis with a step-wise regression demonstrated that age, lactate, and QRS duration of the initial-ECG were significant predictors of all-cause mortality (Odds ratio (OR): 1.04, 1.21, 1.02, p: 0.002, 0.001, 0.001, respectively). Kaplan-Meier analysis revealed that a complete right bundle branch block (CRBBB) of initial-ECG and presence of atrial fibrillation were associated with an increased risk of all-cause mortality (Picture).
Serial change of ECG variables Initial-ECG 2nd-ECG Group S Group D p Group S Group D p Heart Rate [/min] 109±23 105±31 0.527 88±21 94±23 0.341 Af [N,%] 10 (25%) 27 (52%) 0.018* 3 (9%) 6 (26%) 0.134 QRS duration [ms] 111±18 139±33 0.001* 107±29 111±30 0.623 Morphology 0.001* 0.284 – Normal [N,%] 30 (75%) 10 (19%) 29 (81%) 14 (61%) – CRBBB [N,%] 5 (13%) 30 (57%) 5 (14%) 5 (22%) – CLBBB [N,%] 1 (2%) 0 0 1 (4%) – IVCD [N,%] 4 (10%) 13 (24%) 2 (6%) 3 (13%) Comparing variables between group S and group D stratified by initial ECG and delayed ECG. QRS morphology were examined, normal, complete right bundle branch block (CRBBB), complete left bundle branch block (CLBBB), and unspecific interventricular conduction delay (IVCD).
Study flow diagram, KM curve analysis
Conclusions
The QRS duration and morphology upon resuscitation were associated with an increased risk of all-cause mortality following OHCA.
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Shimizu M, Iiya M, Hara K, Ohmori M, Taomoto Y, Kaneda T, Yamakami Y, Shimada H, Manno T, Isshiki A, Kimura S, Fujii H, Suzuki M, Nishizaki M. P5643Simple 12-leads electrocardiography can predict cardiac death in patients with complete left bundle branch block. Eur Heart J 2019. [DOI: 10.1093/eurheartj/ehz746.0586] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Abstract
Background
Patients with complete left bundle branch block (CLBBB) generally fall in two categories: CLBBB with good prognosis and poor prognosis. However, a simple electrocardiography (ECG) was considered impossible to predict the two categories.
Purpose
To elucidate the possibility of 12-leads ECG for predicting cardiac prognosis in patients with CLBBB
Methods
To estimate myocardial damage and left ventricular function, the ECG was performed with semiconductor SPECT simultaneously. Among consecutive 5864 patients who underwent ECG gated SPECT, finally 103 sinus-rhythm patients were enrolled. The observed period of them was median 632 days, and primary endpoint was set as cardiac death.
Results
Eight patients fell into cardiac death. Cox univariate analysis showed ventricular activation time (VAT: duration from onset of Q wave to peak of R wave) in V1 lead, T wave amplitude in aVR (aVR T-amp), and multiple fragmented QRS (At least 2 fQRS in LV anterior/inferior/lateral wall), and left ventricular ejection fraction, standard deviation of phase analysis (Phase SD), and summed rest score were significant predictors. After optimization of all significant continuous predictors by ROC curve analysis, all the significant predictors were analyzed by multivariate Cox analysis (stepwise regression). VAT in V1 (Hazard ratio: 4.594, P=0.034), aVR T-amp ≥-85microV (HR: 11.11, P=0.029), and Phase SD≥48.7 (HR6.047, P=0.035) were independent predictors. Kaplan-Meyer curve analysis demonstrated VAT V1≥70 and aVR T amp≥-85 showed the worst prognosis (P=0.008).
Cox Regression after Optimization by ROC Univariate Multivariate (Stepwise regression) HR 95% CI P HR 95% CI P VAT I ≥70 6.861 1.759–26.76 0.006 4.594 1.126–18.75 0.034 T amp in aVR ≥−85 27.34 3.458–216.2 0.002 11.11 1.274–96.85 0.029 Multiple fQRS 3.836 1.081–13.61 0.037 LVEF ≤37% 7.250 1.874–28.04 0.004 SD ≥48.7 17.30 3.671–81.57 <0.001 6.047 1.133–32.28 0.035 SRS≥17 4.178 1.206–14.48 0.024 SD: standard deviation of histogram by phase analysis of SPECT; SRS: summed rest score by myocardial perfusion analysis of SPECT.
Conclusion
Simple 12-leads ECG could predict the prognosis of patients with CLBBB.
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Kanehama N, Kimura S, Kawakami T, Tateishi R, Tachibana S, Hayasaka K, Arai H, Hiroki J, Yoshioka K, Kuroda S, Ueshima D, Iwatsuka R, Hayashi T, Mizukami A, Matsumura A. P6154Association between n-3 and n-6 polyunsaturated fatty acids and plaque vulnerability by optical coherence tomography in acute myocardial infarction patients. Eur Heart J 2019. [DOI: 10.1093/eurheartj/ehz746.0760] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Abstract
Background
The values of n-3 and n-6 polyunsaturated fatty acids (PUFAs) like low eicosapentaenoic acid (EPA) /arachidonic acid (AA) ratio are known to be associated with cardiovascular events, however their relationship with coronary plaque vulnerability in acute myocardial infarction (AMI) is not revealed.
Purpose
We evaluated the relationship between n-3 and n-6 PUFAs and coronary plaque vulnerability assessed by optical coherence tomography (OCT) in AMI patients.
Methods
We investigated 79 AMI lesions (51 ST elevated myocardial infarction (STEMI) lesions and 28 non-STEMI lesions) that had undergone emergency percutaneous coronary intervention using OCT. Coronary plaque characteristics by OCT were compared with n-3 and n-6 PUFAs values which were measured on admission.
Results
Of all AMI lesions (n=79), 43 thin-cap fibroatheroma (TCFA) and 35 plaque rapture (PR) were detected by OCT. Lesions with TCFA had no significant relationship with n-3 and n-6 PUFAs values, whereas lesion with PR had significantly lower EPA values than those without (55.8±29.5 vs 74.3±37.1 μg/ml, p=0.018). Median low-density lipoprotein (LDL) cholesterol value was 117 (98–137) mg/dl and sub-analysis in patients who had lower LDL cholesterol values than median (n=39) revealed that EPA values were significantly lower in lesions with TCFA (56.3±30.9 vs 85.3±47.7 μg/ml, p=0.03). In STEMI patients, the values of EPA and EPA/AA ratio were significantly lower in lesions with TCFA (EPA: 55.5±22.8 vs 80.8±46.1 μg/ml, p=0.01; EPA/AA ratio: 0.34±0.16 vs 0.50±0.36, p=0.03). STEMI patients who had lower LDL cholesterol values <114 mg/dl of median (n=26), the values of EPA, EPA/AA ratio, and EPA+ docosahexaenoic acid (DHA) /AA ratio were significantly lower in lesions with TCFA (EPA: 51.4±20.7 vs 93.1±53.0 μg/ml, p=0.01; EPA/AA ratio: 0.37±0.16 vs 0.67±0.41, p=0.01; EPA+DHA/AA ratio: 1.13±0.41 vs 1.63±0.76, p=0.04). In STEMI patients with lower LDL cholesterol values, EPA/AA ratio positively correlated with fibrous cap thickness (Spearman, ρ=0.35, p=0.08). The cutoff value of EPA/AA ratio predicting the existence of TCFA was 0.52 (area under the curve 0.78, sensitivity 93.8%, specificity 70.0%, p=0.02).
Conclusion
This study demonstrated that n-3 and n-6 PUFAs values were associated with coronary plaque vulnerability by OCT in AMI patients, especially in STEMI. These results suggest that n-3 and n-6 PUFAs may be residual risk markers of severe acute cardiovascular events in patients with low LDL cholesterol values.
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Kakuta T, Komatsu S, Kojima K, Fujii H, Kimura S, Dai K, Kawakami H, Matsuoka H, Higuchi Y, Abe H, Inoue T, Okumura Y, Asakura M, Hirayama A, Kodama K. P1831Prediction of cardiovascular events by atheromatous plaques detected by non-obstructive general angioscopy: two-year results of EAST-NOGA Registry. Eur Heart J 2019. [DOI: 10.1093/eurheartj/ehz748.0583] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Abstract
Background
Non-obstructive general angioscopy (NOGA) has revealed the intimal damages or atheromatous plaques as well as its spontaneous rupture of the aorta. Recent study revealed that plaque debris or different size of cholesterol crystals were detected in the blood above the spontaneous ruptured aortic plaque observed by NOGA and these plaque materials might cause the peripheral organ damages as the embolic source. These various morphological changes may cause the acute aortic events or atheroembolic events on the peripheral organs, such as brain, kidney, peripheral artery and so on.
Purpose
EAST-NOGA (Evaluation of AtheroSclerotic and rupture events by Non-Obstructive General Angioscopy) is a multi-center prospective observational study to assess the relationship between the findings of NOGA and future cardiovascular events.
Methods
Five hundred and seventy-seven patients with atherosclerotic cardiovascular disease who underwent NOGA study. The major cerebrocardiovascular events including cardiovascular death, non-fatal myocardial infarction, non-fatal cerebral infarction, and acute aortic syndrome were accumulated during the 2-year follow-up after NOGA study.
Results
The median number of aortic atheromatous plaques was 6 [IQR: 3–12]. A total of 514 patients were followed up (89.1%). The mean follow-up duration was 757±120 days. Major adverse cardiovascular events developed in 23 (4.5%) during 2 years follow-up. Patients with MACE and cerebral infarction, had significantly greater number of aortic atheromatous plaques (11 [5–19] vs. 6 [3–11], p<0.001, 12 [4–20] vs. 6 [3–12], p=0.014, respectively). In a univariate analysis, the number of aortic atheromatous plaques and ruptured plaque were significant predictors of MACE (HR: 1.09 95% confidence interval 1.05–1.14, p<0.001) and (HR: 1.12, 95% confidence interval 1.02–1.23, p=0.02). In a multivariate logistic analysis, the number of aortic atheromatous plaques is one of the independent predictors of MACE (HR 1.05, 95% confidence interval 1.00–1.10, p=0.032).
Conclusion
The number of atheromatous plaques identified by NOGA has a significant relation to the onset of cerebral infarction, which suggest the atheromatous plaque were vulnerable and ruptured spontaneously, then cause the aortogenic cerebral infarction. The NOGA study would be useful for predicting the futured atheroembolic events.
Acknowledgement/Funding
None
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Kimura S, Khalil IA, Elewa YHA, Harashima H. Spleen selective enhancement of transfection activities of plasmid DNA driven by octaarginine and an ionizable lipid and its implications for cancer immunization. J Control Release 2019; 313:70-79. [PMID: 31526828 DOI: 10.1016/j.jconrel.2019.09.009] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2019] [Revised: 08/13/2019] [Accepted: 09/14/2019] [Indexed: 12/21/2022]
Abstract
Efficiently delivering plasmid DNA (pDNA) to the spleen is particularly significant for DNA immunization. However, increasing the efficiency of gene expression in spleen cells for achieving a therapeutic effect remains a serious challenge. An ideal spleen-targeted system should avoid liver uptake and should efficiently transfect specific functional spleen cells. Here, we report on pDNA nanocarriers with enhanced transfection in spleen cells driven by synergism between an octaarginine (R8) peptide and YSK05; a pH-responsive ionizable lipid. A double-coating design is essential for enhancing spleen selective transfection which is significantly affected by the total amount of lipid and the composition of the outer coat. The optimized R8/YSK system shows a high gene expression in the spleen with a high spleen/liver ratio and a surprising ability to target spleen B cells. Compared to other organs, the high spleen activity cannot be explained based on the amount of pDNA delivered to each organ, indicating that the system is extremely efficient in transfecting spleen cells. The system can be used in cancer immunization where a strong anti-tumor effect was observed in mice immunized with the R8/YSK system encapsulating antigen-encoding pDNA. The R8/YSK system holds great promise for future applications in the field of DNA vaccination.
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Kashiwada T, Nishioka A, Aragane N, Kimura S. Paclitaxel plus ramucirumab combination therapy as second-line therapy in elderly patients with metastatic advanced gastric cancer: A single-center retrospective study. Ann Oncol 2019. [DOI: 10.1093/annonc/mdz155.330] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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Tanaka Y, Kimura S, Ishii Y, Tateda K. Equol inhibits growth and spore formation of Clostridioides difficile. J Appl Microbiol 2019; 127:932-940. [PMID: 31211883 DOI: 10.1111/jam.14353] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2019] [Revised: 06/01/2019] [Accepted: 06/12/2019] [Indexed: 12/15/2022]
Abstract
AIMS Equol is a nonsteroidal oestrogen of the isoflavone class. We investigated the antibacterial ability of equol with respect to the growth rate, toxin production and spore-forming abilities of Clostridioides difficile BI/027/NAP1. METHODS AND RESULTS Isoflavones, or female hormones, were added to bacterial culture, which was grown at 35°C. The absorbance of the culture was measured at various time points for evaluating the growth inhibition. The toxin levels in the media and morphological changes were also assessed. To evaluate the influence of equol on the sporulation of C. difficile, cells were collected at various time points from the equol-supplemented culture and the number of spores was counted. Our results show that equol inhibits bacterial growth in a concentration-dependent manner. However, it does not inhibit the production of toxin by C. difficile. Other isoflavones and female hormones did not inhibit the C. difficile growth. At the 14th day, approximately 600 spores were present in the control medium and only six were seen in the equol-containing medium. CONCLUSION Our results suggest that equol may directly inhibit the C. difficile growth in a concentration-dependent manner and spore formation. SIGNIFICANCE AND IMPACT OF THE STUDY This is the first report on the antimicrobial ability of equol.
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Hidese R, Toyoda M, Yoshino KI, Fukuda W, Wihardja GA, Kimura S, Fujita J, Niitsu M, Oshima T, Imanaka T, Mizohata E, Fujiwara S. The C-terminal flexible region of branched-chain polyamine synthase facilitates substrate specificity and catalysis. FEBS J 2019; 286:3926-3940. [PMID: 31162806 DOI: 10.1111/febs.14949] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2019] [Revised: 05/03/2019] [Accepted: 06/01/2019] [Indexed: 01/26/2023]
Abstract
Branched-chain polyamine synthase (BpsA) catalyzes sequential aminopropyl transfer from the donor, decarboxylated S-adenosylmethionine (dcSAM), to the acceptor, linear-chain polyamine, resulting in the production of a quaternary-branched polyamine via tertiary branched polyamine intermediates. Here, we analyzed the catalytic properties and X-ray crystal structure of Tth-BpsA from Thermus thermophilus and compared them with those of Tk-BpsA from Thermococcus kodakarensis, which revealed differences in acceptor substrate specificity and C-terminal structure between these two enzymes. To investigate the role of the C-terminal flexible region in acceptor recognition, a region (QDEEATTY) in Tth-BpsA was replaced with that in Tk-BpsA (YDDEESSTT) to create chimeric Tth-BpsA C9, which showed a severe reduction in catalytic efficiency toward N4 -aminopropylnorspermidine, but not toward N4 -aminopropylspermidine, mimicking Tk-BpsA substrate specificity. Tth-BpsA C9 Tyr346 and Thr354 contributed to discrimination between tertiary branched-chain polyamine substrates, suggesting that the C-terminal region of BpsA recognizes acceptor substrates. Liquid chromatography-tandem mass spectrometry analysis on a Tk-BpsA reaction mixture with dcSAM revealed two aminopropyl groups bound to two of five aspartate/glutamate residues (Glu339 , Asp342 , Asp343 , Glu344 , and Glu345 ) in the C-terminal flexible region. Mutating each of these five amino acid residues to asparagine/glutamine resulted in a slight decrease in activity. The quadruple mutant D342N/D343N/E344Q/E345Q exhibited a severe reduction in catalytic efficiency, suggesting that these aspartate/glutamate residues function to receive aminopropyl chains. In addition, the X-ray crystal structure of the Tk-BpsA ternary complex bound to N4 -bis(aminopropyl)spermidine revealed that Asp126 and Glu259 interacted with the aminopropyl moiety in N4 -aminopropylspermidine.
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