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Yoshiaki Taniyama

Bio: Yoshiaki Taniyama is an academic researcher from Osaka University. The author has contributed to research in topics: Hepatocyte growth factor & Periostin. The author has an hindex of 40, co-authored 127 publications receiving 6850 citations. Previous affiliations of Yoshiaki Taniyama include St. Elizabeth's Medical Center & Shimadzu Corp..


Papers
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TL;DR: Transfection of p53 plasmid with the use of this method should be useful for safe clinical gene therapy without a viral vector system, and no apparent toxicity could be detected in blood vessels transfected withplasmid DNA with ultrasound and Optison.
Abstract: Background— Although viral vector systems are efficient to transfect foreign genes into blood vessels, safety issues remain in relation to human gene therapy. In this study, we examined the feasibility of a novel nonviral vector system by using high-frequency, low-intensity ultrasound irradiation for transfection into blood vessels. Methods and Results— Luciferase plasmid mixed with or without echo contrast microbubble (Optison) was transfected into cultured human vascular smooth muscle cells (VSMC) and endothelial cells (EC) with the use of ultrasound. Interestingly, luciferase activity was markedly increased in both cell types treated with Optison. We then transfected luciferase plasmid mixed with Optison by means of therapeutic ultrasound into rat artery. Two days after transfection, luciferase activity was significantly higher in carotid artery transfected with luciferase gene with Optison and ultrasound than with plasmid alone. In addition, we transfected an anti-oncogene (p53) plasmid into carotid a...

452 citations

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TL;DR: Despite no obstructive lesion of the vessel, TIMI 2 is caused by advanced microvascular damage and is a highly specific, although not sensitive, predictor of poor functional outcomes in patients with acute myocardial infarction.
Abstract: Background Epicardial coronary flow is occasionally reduced even after coronary intervention despite the absence of vessel obstruction in patients with acute myocardial infarction. Our aim was to clarify the cause and outcomes of radiocontrast slow filling in patients with reperfused acute anterior myocardial infarction by assessing microvascular damage with the use of myocardial contrast echocardiography (MCE) and functional outcomes. Methods and Results We carefully reviewed the cineangiograms of 86 patients who achieved coronary revascularization within 12 hours of the onset and underwent MCE before and soon after recanalization with the intracoronary injection of sonicated microbubbles. Antegrade coronary flow after recanalization was graded by two observers based on Thrombolysis in Myocardial Infarction (TIMI) trial flow grades. Left ventricular ejection fraction was measured on the day of infarction and 1 month later. TIMI grade 2 was observed in 18 patients (21%), and the other 68 patients manifest...

435 citations

Journal ArticleDOI
TL;DR: Transfection of HGF plasmid by the ultrasound-Optison method could be useful for safe clinical gene therapy to treat peripheral arterial disease without a viral vector system.
Abstract: Although clinical trials of stimulation of angiogenesis by transfection of angiogenic growth factors using naked plasmid DNA or adenoviral vector have been successful, there are still unresolved problems for human gene therapy such as low transfection efficiency and safety. From this viewpoint, it is necessary to develop safe and efficient novel nonviral gene transfer methods. As therapeutic ultrasound induces cell membrane permeabilization, ultrasound irradiation might increase the transfection efficiency of naked plasmid DNA into skeletal muscle. Thus, we examined the transfection efficiency of naked plasmid DNA using ultrasound irradiation with echo contrast microbubble (Optison) in vitro and in vivo experiments. First, we examined the feasibility of ultrasound-mediated transfection of naked plasmid DNA into skeletal muscle cells. Luciferase plasmid mixed with or without Optison was transfected into cultured human skeletal muscle cells using ultrasound (1 MHz; 0.4 W(2)) for 30 s. Interestingly, luciferase activity was markedly increased in cells treated with Optison, while little luciferase activity could be detected without Optison (P < 0.01). Electron microscopy demonstrated the transient formation of holes (less than 5 microM) in the cell surface, which could possibly explain the rapid migration of the transgene into the cells. Next, we studied the in vivo transfection efficiency of naked plasmid DNA using ultrasound with Optison into skeletal muscle. Two days after transfection, luciferase activity in skeletal muscle transfected with Optison using ultrasound was significantly increased about 10-fold as compared with plasmid alone. Successful transfection was also confirmed by beta-galactosidase staining. Finally, we examined the feasibility of therapeutic angiogenesis using naked hepatocyte growth factor (HGF) plasmid in a rabbit ischemia model using the ultrasound-Optison method. Five weeks after transfection, the angiographic score and the number of capillary density in rabbits transfected with Optison using ultrasound was significantly increased as compared with HGF plasmid alone (P < 0.01), accompanied by a significant increase in blood flow and blood pressure ratio (P < 0.01). Overall, the ultrasound transfection method with Optison enhanced the transfection efficiency of naked plasmid DNA in vivo as well as in vitro. Transfection of HGF plasmid by the ultrasound-Optison method could be useful for safe clinical gene therapy to treat peripheral arterial disease without a viral vector system.

410 citations

Journal ArticleDOI
TL;DR: Intravenous nicorandil in conjunction with coronary angioplasty is associated with better functional and clinical outcomes compared to angiopLasty alone in patients with an anterior AMI, and myocardial contrast echocardiography findings imply that an improvement in microvascular function with nicor andil may be attributable to this better outcome.

360 citations

Journal ArticleDOI
TL;DR: In the presence of decreased endogenous HGF, administration of rhHGF induced therapeutic angiogenesis in the rabbit ischemic hind limb model, as potential cytokine supplement therapy for peripheral arterial disease.
Abstract: —Hepatocyte growth factor (HGF) exclusively stimulates the growth of endothelial cells without replication of vascular smooth muscle cells and acts as a survival factor against endothelial cell death. Therefore we hypothesized that a decrease in local vascular HGF might be related to the pathogenesis of peripheral arterial disease. We initially evaluated vascular HGF concentration in the vessels of patients with arteriosclerosis obliterans. Consistent with in vitro findings that hypoxia downregulated vascular HGF production, vascular HGF concentration in the diseased segments of vessels from patients with arteriosclerosis obliterans was significantly decreased as compared with disease-free segments from the same patients ( P <0.05), accompanied by a marked reduction in HGF mRNA. On the other hand, a novel therapeutic strategy for ischemic diseases that uses angiogenic growth factors to expedite and/or augment collateral artery development has recently been proposed. Thus in view of the decreased endogenous vascular HGF, rhHGF (500 μg/animal) was intra-arterially administered through the internal iliac artery of rabbits in which the femoral artery was excised to induce unilateral hind limb ischemia, to evaluate the angiogenic activity of HGF, which could potentially have a beneficial effect in hypoxia. Administration of rhHGF twice on days 10 and 12 after surgery produced significant augmentation of collateral vessel development on day 30 in the ischemic model as assessed by angiography ( P <0.01). Serial angiograms revealed progressive linear extension of collateral arteries from the origin stem artery to the distal point of the reconstituted parent vessel in HGF-treated animals. In addition, we examined the feasibility of intravenous administration of rhHGF in a moderate ischemia model. Importantly, intravenous administration of rhHGF also resulted in a significant increase in angiographic score as compared with vehicle ( P <0.01). Overall, a decrease in vascular HGF might be related to the pathogenesis of peripheral arterial disease. In the presence of decreased endogenous HGF, administration of rhHGF induced therapeutic angiogenesis in the rabbit ischemic hind limb model, as potential cytokine supplement therapy for peripheral arterial disease.

272 citations


Cited by
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TL;DR: Alice K. Jacobs, MD, FACC, FAHA, Chair Jeffrey L. Anderson, PhD, CCNS, CCRN, FAH, Chair-Elect - The first female FACC-FAHA board member to be elected in the history of the sport.
Abstract: Alice K. Jacobs, MD, FACC, FAHA, Chair Jeffrey L. Anderson, MD, FACC, FAHA, Chair-Elect Nancy Albert, PhD, CCNS, CCRN, FAHA Mark A. Creager, MD, FACC, FAHA Steven M. Ettinger, MD, FACC Robert A. Guyton, MD, FACC Jonathan L. Halperin, MD, FACC, FAHA Judith S. Hochman, MD, FACC, FAHA

3,040 citations

Journal ArticleDOI
TL;DR: Cancer-associated fibroblasts (CAFs) become synthetic machines that produce many different tumour components and have a role in creating extracellular matrix structure and metabolic and immune reprogramming of the tumour microenvironment with an impact on adaptive resistance to chemotherapy.
Abstract: Cancer is associated with fibroblasts at all stages of disease progression. This Review discusses the pleiotropic actions of cancer-associated fibroblasts (CAFs) on tumour cells and postulates that they are likely to be a heterogeneous and plastic population of cells in the tumour microenvironment. Among all cells, fibroblasts could be considered the cockroaches of the human body. They survive severe stress that is usually lethal to all other cells, and they are the only normal cell type that can be live-cultured from post-mortem and decaying tissue. Their resilient adaptation may reside in their intrinsic survival programmes and cellular plasticity. Cancer is associated with fibroblasts at all stages of disease progression, including metastasis, and they are a considerable component of the general host response to tissue damage caused by cancer cells. Cancer-associated fibroblasts (CAFs) become synthetic machines that produce many different tumour components. CAFs have a role in creating extracellular matrix (ECM) structure and metabolic and immune reprogramming of the tumour microenvironment with an impact on adaptive resistance to chemotherapy. The pleiotropic actions of CAFs on tumour cells are probably reflective of them being a heterogeneous and plastic population with context-dependent influence on cancer.

2,597 citations

Journal ArticleDOI
TL;DR: The medical profession should play a central role in evaluating the evidence related to drugs, devices, and procedures for the detection, management, and prevention of disease as mentioned in this paper, and when properly applied, expert analysis of available data on the benefits and risks of these therapies and procedures can

2,495 citations

Journal ArticleDOI
TL;DR: Guidelines and Expert Consensus Documents summarize and evaluate all currently available evidence on a particular issue with the aim of assisting physicians in selecting the best management strategies for a typical patient, suffering from a given condition, taking into account the impact on outcome, as well as the risk/benefit ratio of particular diagnostic or therapeutic means.
Abstract: Guidelines and Expert Consensus Documents summarize and evaluate all currently available evidence on a particular issue with the aim of assisting physicians in selecting the best management strategies for a typical patient, suffering from a given condition, taking into account the impact on outcome, as well as the risk/benefit ratio of particular diagnostic or therapeutic means. Guidelines are no substitutes for textbooks. The legal implications of medical guidelines have been discussed previously. A great number of Guidelines and Expert Consensus Documents have been issued in recent years by the European Society of Cardiology (ESC) as well as by other societies and organizations. Because of the impact on clinical practice, quality criteria for the development of guidelines have been established in order to make all decisions transparent to the user. The recommendations for formulating and issuing ESC Guidelines and Expert Consensus Documents can be found on the ESC website (http://www.escardio.org/knowledge/guidelines/rules). In brief, experts in the field are selected and undertake a comprehensive review of the published evidence for management and/or prevention of a given condition. Unpublished clinical trial results have not been taken into account. A critical evaluation of diagnostic and therapeutic procedures is performed including assessment of the risk/benefit ratio. Estimates of expected health outcomes for larger societies are included, where data exist. The level of evidence and the strength of recommendation of particular treatment options are weighed and graded according to predefined scales, as outlined in Tables 1 and 2 . The experts of the writing panels have provided disclosure statements of all relationships they may have which might be perceived as real or potential sources of conflicts of interest. These disclosure forms are kept on file at the European Heart House, headquarters of the ESC. Any changes in conflict of interest that arise during the writing period …

2,297 citations

Journal ArticleDOI
TL;DR: A unifying hypothesis is proposed whereby hyperglycemia and FFA-induced activation of the nuclear factor-kappaB, p38 MAPK, and NH2-terminal Jun kinases/stress-activated protein kinases stress pathways plays a key role in causing late complications in type 1 and type 1 diabetes, along with insulin resistance and impaired insulin secretion in type 2 diabetes.
Abstract: In both type 1 and type 2 diabetes, the late diabetic complications in nerve, vascular endothelium, and kidney arise from chronic elevations of glucose and possibly other metabolites including free fatty acids (FFA). Recent evidence suggests that common stress-activated signaling pathways such as nuclear factor-kappaB, p38 MAPK, and NH2-terminal Jun kinases/stress-activated protein kinases underlie the development of these late diabetic complications. In addition, in type 2 diabetes, there is evidence that the activation of these same stress pathways by glucose and possibly FFA leads to both insulin resistance and impaired insulin secretion. Thus, we propose a unifying hypothesis whereby hyperglycemia and FFA-induced activation of the nuclear factor-kappaB, p38 MAPK, and NH2-terminal Jun kinases/stress-activated protein kinases stress pathways, along with the activation of the advanced glycosylation end-products/receptor for advanced glycosylation end-products, protein kinase C, and sorbitol stress pathways, plays a key role in causing late complications in type 1 and type 2 diabetes, along with insulin resistance and impaired insulin secretion in type 2 diabetes. Studies with antioxidants such as vitamin E, alpha-lipoic acid, and N-acetylcysteine suggest that new strategies may become available to treat these conditions.

2,090 citations