Publications by authors named "Hajime Ichimura"

To determine the optimal perfusion volume for the celiac artery (CA) and superior mesenteric artery (SMA) in a porcine model. Fifteen Yorkshire pigs (46.7 ± 5.

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Objective: Although endovascular aneurysm repair (EVAR) is a standard treatment for abdominal aortic aneurysms, postprocedural aneurysm expansion caused by types II and V endoleaks (ELs) remains challenging. Aortic graft replacement is a definitive solution, but is associated with high morbidity and mortality, especially in elderly patients. Aneurysmorrhaphy has emerged as a less invasive alternative.

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Injured human hearts are fibrotic, whereas zebrafish hearts functionally regenerate following myocardial injury. The unique regeneration niche microenvironment has been extensively studied in zebrafish hearts. However whether this can be extrapolated to humans remains unclear owing to significant species differences.

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Background: Although quality of life (QOL) is an outcome of postoperative cardiac rehabilitation (CR), its course and related factors from postoperative hospitalization to the post-discharge period have not been adequately investigated. Additionally, the EuroQol-5Dimension-5Level (EQ-5D-5L) index score has not been characterized over the same period. We aimed to characterize QOL changes assessed by the EQ-5D-5L, over the period from hospitalization to 1 year post-discharge, in patients post-cardiac and thoracic aortic surgery, and investigate the factors associated with these temporal changes.

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Background: The clinical application of human induced pluripotent stem cell-derived cardiomyocytes (CMs) for cardiac repair commenced with the epicardial delivery of engineered cardiac tissue; however, the feasibility of the direct delivery of human induced pluripotent stem cell-derived CMs into the cardiac muscle layer, which has reportedly induced electrical integration, is unclear because of concerns about poor engraftment of CMs and posttransplant arrhythmias. Thus, in this study, we prepared purified human induced pluripotent stem cell-derived cardiac spheroids (hiPSC-CSs) and investigated whether their direct injection could regenerate infarcted nonhuman primate hearts.

Methods: We performed 2 separate experiments to explore the appropriate number of human induced pluripotent stem cell-derived CMs.

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Article Synopsis
  • Exon-skipping therapy is a potential treatment for Duchenne muscular dystrophy (DMD) by targeting specific exons in the dystrophin gene, particularly focusing on a mild variant known as Δ3-9.
  • A study compared human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs) with either the Δ3-9 deletion, a frameshifting deletion (Δ3-7), or intact dystrophin, revealing that the Δ3-9 variant mimicked the expression patterns and electrical properties of healthy heart cells.
  • Antisense oligonucleotides targeting exon 8 successfully restored functional dystrophin and improved cell characteristics in the Δ3-7 cells, suggesting that modifying
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Background: Human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs) can be used to treat heart diseases; however, the optimal maturity of hiPSC-CMs for effective regenerative medicine remains unclear. We aimed to investigate the benefits of long-term cultured mature hiPSC-CMs in injured rat hearts.

Methods: Cardiomyocytes were differentiated from hiPSCs via monolayer culturing, and the cells were harvested on day 28 or 56 (D28-CMs or D56-CMs, respectively) after differentiation.

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Pluripotent stem cell (PSC)-derived cardiomyocytes are a promising source of cells in myocardial regeneration therapy for end-stage heart failure. Because most previous reports have focussed on xenotransplantation models using immunocompromised animals, studies on immune rejection in allogeneic transplantation models are needed for preclinical and clinical applications. Human leukocyte antigen (HLA) plays an important role in allogeneic transplantation, and cell bank projects are currently underway worldwide to stock induced pluripotent stem cells (iPSCs) generated from healthy individuals with homozygous HLA haplotypes.

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A 72-year-old man, who was treated 10 years earlier with endovascular aortic aneurysm repair, presented with a fever. Considering the concern of stent graft infection, the patient was treated with antibiotics, but his condition did not improve. He underwent stent graft resection and reconstruction with a Dacron graft.

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Advances in stem cell biology have facilitated cardiac regeneration, and many animal studies and several initial clinical trials have been conducted using human pluripotent stem cell-derived cardiomyocytes (PSC-CMs). Most preclinical and clinical studies have typically transplanted PSC-CMs via the following two distinct approaches: direct intramyocardial injection or epicardial delivery of engineered heart tissue. Both approaches present common disadvantages, including a mandatory thoracotomy and poor engraftment.

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Purpose: Fulminant myocarditis presents as acute severe heart failure and requires mechanical cardiocirculatory support. Left-ventricular (LV) decompression is necessary for the successful recovery of these patients. This retrospective study aimed to evaluate the functional outcomes of providing central extracorporeal membrane oxygenation (ECMO) with LV decompression for the treatment of refractory fulminant myocarditis.

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This study aimed to investigate the relationship between heart rate variability (HRV), a parameter of the autonomic nervous system activity (ANSA), and postoperative delirium and postoperative events. This retrospective cohort study included elderly patients aged 65 years or older who were admitted to the intensive care unit (ICU) after cardiovascular surgery. ANSA was measured using HRV parameters for 1 h at daytime and 1 h at night-time before ICU discharge.

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Recently, activities of daily living (ADL) were identified as a prognostic factor among elderly patients with heart disease; however, a specific association between ADL and prognosis after cardiac and aortic surgery is not well established. We aimed to clarify the impact of ADL capacity at discharge on prognosis in elderly patients after cardiac and aortic surgery.This retrospective cohort study included 171 elderly patients who underwent open operation for cardiovascular disease in a single center (median age: 74 years; men: 70%).

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Recent evidence has provided exciting proof of concepts for the use of pluripotent stem cell-derived cardiomyocytes (PSC-CMs) for cardiac repair; however, large animal studies, which better reflect human disease, are required for clinical application. Here, we describe how to create myocardial infarction in cynomolgus monkey followed by transplantation of PSC-CMs. This method ensures the establishment of a myocardial infarction model and enables reliable PSC-CM transplantation.

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Objectives: We aimed to identify predictors of postoperative permanent neurological deficits (PNDs) and evaluate the early management of cerebral perfusion in patients undergoing surgical repair of acute type A aortic dissection with cerebral malperfusion.

Methods: Between October 2009 and September 2018, a total of 197 patients with acute type A aortic dissection underwent aortic replacement. Of these, 42 (21.

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Accumulating evidence suggests that human pluripotent stem cell-derived cardiomyocytes can affect "heart regeneration", replacing injured cardiac scar tissue with concomitant electrical integration. However, electrically coupled graft cardiomyocytes were found to innately induce transient post-transplant ventricular tachycardia in recent large animal model transplantation studies. We hypothesised that these phenomena were derived from alterations in the grafted cardiomyocyte characteristics.

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Objectives: Although skeletal muscle quantity is linked to surgical outcomes, quality remains unexamined. In this study, we evaluated whether skeletal muscle quality and quantity could predict surgical outcomes in acute type A aortic dissection (ATAAD).

Methods: Skeletal muscle quality and quantity were evaluated using computed tomography (CT) values and the psoas muscle mass index, respectively.

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Background: Although frailty is used to predict morbidity and mortality, its effect on the outcomes of acute type A aortic dissection has not been examined. Therefore, the objective of this study was to evaluate the role of frailty in predicting postoperative morbidity and mortality of patients with acute type A aortic dissection.

Methods: A retrospective analysis of a prospectively maintained database was undertaken for all patients (n = 310) undergoing aortic surgery between May 2004 and March 2017.

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Pluripotent stem cell-derived cardiomyocytes show great promise in regenerating the heart after myocardial infarction; however, several uncertainties exist that must be addressed before clinical trials. One practical issue is graft survival following transplantation. Although a pro-survival cocktail with Matrigel has been shown to enhance graft survival, the use of Matrigel may not be clinically feasible.

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Pluripotent stem cells (PSCs) have gained interest for cell-based regenerative therapies because of their capacity to differentiate into most somatic cell types, including cardiomyocytes. Remarkable progress in the generation of PSC-derived cardiomyocytes has been made in this decade, and recent preclinical transplantation studies using various animal models have provided proof-of-principle for their use in heart regeneration. However, several obstacles preclude their effective and safe clinical application for cardiac repair, including the need for approaches that prevent tumorigenesis, arrhythmogenesis, and immune rejection.

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Induced pluripotent stem cells (iPSCs) constitute a potential source of autologous patient-specific cardiomyocytes for cardiac repair, providing a major benefit over other sources of cells in terms of immune rejection. However, autologous transplantation has substantial challenges related to manufacturing and regulation. Although major histocompatibility complex (MHC)-matched allogeneic transplantation is a promising alternative strategy, few immunological studies have been carried out with iPSCs.

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Cardiac tumors and tumor-like lesions are uncommon; most are true neoplasms. We here report a case of a pericoronary tumor-like lesion surrounding the right coronary artery in a 39-year-old man who presented with fever and chest pain. Although clarithromycin was administered for 1 week, his fever persisted.

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Background: Photodynamic therapy (PDT) has been proven to be a promising therapeutic modality for selected dysplasias and malignancies in a variety of organs. We assessed the effectiveness of PDT for treating cervical intraepithelial neoplasia (CIN) by cytological and histological examinations and investigated its impact on human papillomavirus (HPV) infection.

Methods: A series of 31 patients with CIN (2 with CIN2, 29 with CIN3) were given polyhematoporphyrin ether/ester (PHE) 2 mg/kg IV.

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Objective: To evaluate the role of transarterial embolization followed by hysteroscopic removal of a placental polyp with preservation of reproductive capacity.

Study Design: Three patients with placental polyps with abundant blood flow, suspected on ultrasonography with color Doppler imaging and on magnetic resonance imaging, were studied. They underwent transarterial embolization followed by hysteroscopic removal of the polyp.

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