Publications by authors named "Umemura S"

Cavitation bubbles are known to accelerate therapeutic effects of ultrasound. Although negative acoustic pressure is the principle factor of cavitation, positive acoustic pressure has a role for bubble cloud formation at a high intensity of focused ultrasound when cavitation bubbles provide pressure release surfaces converting the pressure from highly positive to negative. In this study, the second-harmonic was superimposed onto the fundamental acoustic pressure to emphasize either peak positive or negative pressure.

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Background: Metabolic disorders with visceral obesity have become a major medical problem associated with the development of hypertension, type 2 diabetes, and dyslipidemia and, ultimately, life-threatening cardiovascular and renal diseases. Adipose tissue dysfunction has been proposed as the cause of visceral obesity-related metabolic disorders, moving the tissue toward a proinflammatory phenotype.

Methods And Results: Here we first report that adipose tissues from patients and mice with metabolic disorders exhibit decreased expression of ATRAP/Agtrap, which is a specific binding modulator of the angiotensin II type 1 receptor, despite its abundant expression in adipose tissues from normal human and control mice.

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Background: Functionalized fullerenes, such as polyhydroxy fullerenes (PHF), have attracted particular attention due to their water solubility and their potential application in tumor imaging and therapy as carbon nanomaterials. In this study, the sonodynamically-induced antitumor effect of PHF was investigated.

Materials And Methods: Sonodynamically-induced antitumor effects of PHF in combination with ultrasound were investigated using isolated sarcoma 180 cells and solid tumor from colon 26 carcinoma cells.

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An altered ambulatory blood pressure (BP) and heart rate (HR) profile is related to chronic kidney disease (CKD) and cardiorenal syndrome. In this study, we examined the effects of aliskiren, when added to angiotensin II type 1 receptor blockers, on ambulatory BP and cardiorenal function in CKD. Thirty-six hypertensive CKD patients were randomly assigned to the aliskiren add-on group (n = 18) or the benazepril add-on group (n = 18).

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Background: It remains unknown whether the time course of the antiplatelet effects of clopidogrel differs according to cytochrome P450 (CYP) 2C19 phenotype in Japanese patients with acute coronary syndromes (ACS).

Methods And Results: Platelet reactivity was serially assessed by VerifyNow-P2Y12 assay (Accumetrics, San Diego, CA, USA). Results were expressed as P2Y12-reaction-units (PRU) in 177 patients with ACS who underwent stent implantation and received aspirin plus a 300-mg loading dose of clopidogrel followed by 75 mg/day.

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Background And Aim: The opportunities of endoscopic retrograde cholangiopancreatography (ERCP)-related procedure for hemodialysis (HD) patients have been increasing recently. However, the complication rate of ERCPs in HD patients has not been evaluated sufficiently. We aimed to clarify the feasibility of ERCPs in HD patients.

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Diuretics or calcium channel blockers (CCBs) are used concomitantly with an angiotensin II receptor blocker (ARB). However, it is not established which ARB-based combination therapy is the most effective and safe. This prospective randomized open-label study compared the efficacy and safety of a fixed-dose tablet of losartan (LST)-hydrochlorothiazide (HCTZ) (n = 99) and LST-amlodipine (AML) (n = 77) in Japanese patients whose hypertension was uncontrolled by ARB monotherapy.

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Atherosclerotic diseases, such as coronary artery disease and peripheral artery disease, are systemic disorders and among the leading causes of mortality and morbidity throughout the world. However, the exact pathophysiological mechanisms underlying the development of atherosclerosis remain unknown; currently, atherosclerosis is thought to involve an inflammatory process. Systemic inflammatory reactions and accumulation of immune cells in atherosclerotic lesions in situ are considered essential.

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The case of a 68-year-old woman with purpura nephritis associated with nephrotic syndrome is herein described. The patient's clinical course and the findings of a renal biopsy study revealed purpura nephritis. Following treatment with corticosteroids and intravenous cyclophosphamide accompanied by an angiotensin II type I receptor-blocker, an anti-platelet drug and an hydroxymethylglutaryl (HMG)-CoA, the proteinuria mildly decreased.

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The angiotensin II type 1 receptor (AT1R)-associated protein (ATRAP/Agtrap) promotes constitutive internalization of the AT1R so as to specifically inhibit the pathological activation of its downstream signaling yet preserve the base-line physiological signaling activity of the AT1R. Thus, tissue-specific regulation of Agtrap expression is relevant to the pathophysiology of cardiovascular and renal disease. However, the regulatory mechanism of Agtrap gene expression has not yet been fully elucidated.

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Although patients with Stanford type A acute aortic dissection often show ST-T abnormalities at presentation, the frequency and implication of such findings remain unclear. To clarify these points, admission electrocardiograms from 233 patients admitted ≤6 hours after symptom onset who underwent emergency surgery for type A acute aortic dissection were studied. The prevalence of electrocardiographic (ECG) patterns was 51% for ST-T abnormalities (4% for ST-segment elevation and 47% for ST-segment depression and/or negative T waves), 30% for normal ECG findings or no significant ST-T changes, and 19% for ECG confounders such as bundle branch block or left ventricular hypertrophy.

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Epithelial sodium channels (ENaC) are ion transporters in the aldosterone-sensitive distal nephron that play an important role in sodium reabsorption in the terminal nephron. Our study of inbred C57Bl6/J mice given a high-sodium diet showed increased ENaC expression accompanied by tubular renin activation on qRT-PCR of laser-captured tubule specimens and Western blotting of membrane proteins, despite inhibition of aldosterone. Treatment with an angiotensin-converting-enzyme inhibitor (ACEI) or an angiotensin receptor blocker (ARB) effectively lowered blood pressure.

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Background: Cardiac troponin is a specific biomarker for cardiomyocyte necrosis in acute coronary syndromes. Troponin release from the coronary circulation remains to be determined because of the lower sensitivity of the conventional assay. We sought to determine basal and angina-induced troponin release using a highly sensitive troponin assay.

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Cardiovascular disease (CVD) is a major cause of death in patients with chronic kidney disease (CKD). Patients with CKD are reported to have a significant greater risk of CVD-associated mortality than that of the general population after stratification for age, gender, race, and the presence or absence of diabetes. CKD itself is also an independent risk factor for the development of atherosclerosis, and in particular, patients undergoing dialysis typically bear many of the risk factors for atherosclerosis, such as hypertension, dyslipidemia and disturbed calcium-phosphate metabolism, and commonly suffer from severe atherosclerosis, including peripheral arterial disease (PAD).

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Objective: The purpose of this study is to investigate whether high-intensity focused ultrasound (HIFU) exposure is able to produce a fistula between the bladder and abdominal wall of a fetus with lower urinary tract obstruction (LUTO).

Materials And Methods: We constructed a prototype HIFU transducer in combination with an imaging probe. HIFU was applied to the lower abdomen of a rabbit neonate that was complicated by LUTO as an experimental model to produce a fistula; HIFU was applied in a tank filled with degassed water.

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A fungal strain, Penicillium purpurogenum IAM 15392, produced the azaphilone Monascus pigment homolog when cultured in a medium composed of soluble starch, ammonium nitrate, yeast extract, and citrate buffer, pH 5.0. One of the typical features of violet pigment PP-V [(10Z)-12- carboxyl-monascorubramine] is that pyranoid oxygen is replaced with nitrogen.

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High-intensity focused ultrasound (HIFU) has excellent potential as a non-invasive therapeutic tool in various fields of medicine. We present a case of twin reversed arterial perfusion sequence, in which non-invasive blood flow occlusion in the acardiac fetus was successfully achieved by means of HIFU exposure from outside the maternal abdomen. HIFU was applied to blood vessels of the acardiac fetus at the point at which the umbilical cord entered the body in a series of four procedures at 3-day intervals starting at 13 weeks' gestation, and in a final procedure with higher power at 17 weeks.

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We have previously shown that angiotensin II type 1 receptor-associated protein (ATRAP/Agtrap) interacts with the angiotensin II type 1 receptor and promotes constitutive internalization of the receptor so as to inhibit the pathological activation of its downstream signaling but preserve baseline physiological signaling activity. The present study was designed to investigate the role of renal ATRAP in angiotensin II-dependent hypertension. We generated transgenic mice dominantly expressing ATRAP in the renal tubules, including renal distal tubules.

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Objectives: This study sought to determine the additional clinical value of gait speed to Framingham risk score (FRS), cardiac function, and comorbid conditions in predicting cardiovascular events in patients with ST-segment elevation myocardial infarction.

Background: There is growing evidence that gait speed is inversely associated with all-cause mortality, particularly cardiovascular mortality, among the elderly.

Methods: We undertook a single-center prospective observational study of gait speed in 472 patients with ST-segment elevation myocardial infarction in Japan, between 2001 and 2008.

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Background: The safety and efficacy of combination of platinum agents plus etoposide for patients with small cell lung cancer (SCLC) with pre-existing interstitial lung disease (ILD) is uncertain.

Patients And Methods: Fifty-two patients received platinum agents plus etoposide as first-line chemotherapy for SCLC with pre-existing ILD. The clinical characteristics, treatment outcome and survival of these patients were retrospectively reviewed.

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Objective: A generic cisplatin formulation has replaced the brand-name formulation since November 2003 in our hospital. We retrospectively assessed the renal toxicity caused by the brand-name and generic cisplatin formulations.

Methods: The medical records of patients with thoracic malignancy who were treated at our hospital between November 2000 and April 2008 were reviewed.

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