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1.  Coronary artery vasospasms in a microminipig occurred after placing an ameroid constrictor 
A 12-month-old microminipig, weighing 12.6 kg, showed 3 repeated episodes of transient ST-segment elevation in 24 hr Holter electrocardiogram after placing an ameroid constrictor around the left anterior descending coronary artery. Ventricular fibrillation was noticed just after the cessation of the 24 hr Holter-electrocardiogram recording. Direct current defibrillations and cardiopulmonary resuscitation were performed; however, they were unsuccessful, leading to the animal’s death. Its heart was excised for macroscopic analysis, which indicated that lumen of the ameroid constrictor was not narrowed and that there was no dissection, embolus or thrombus in the coronary arteries, indirectly suggesting that coronary artery vasospasm may have caused the ischemic attacks. Thus, microminipig may possess some potential to have coronary vasospasm.
PMCID: PMC4976282  PMID: 27086718
ameroid constrictor; coronary vasospasm; sudden cardiac death
2.  Feasible induction of coronary artery vasospasm occurred during cardiac catheterization in a microminipig 
A 14 month-old intact microminipig, weighing 8 kg, showed ST-segment elevation in A-B lead electrocardiogram during cardiac catheterization followed by ventricular tachycardia, which degenerated into ventricular fibrillation. Although a direct current defibrillation of 360 J was applied, ventricular tachycardia re-occurred for another 2 times and the direct defibrillation was repeated. After returning to normal sinus rhythm, a marked ST-segment elevation was still observed on leads II, III and aVF together with a remarkable decrease in contractility of inferior wall. The heart was excised for precise macroscopic and histological examinations, but there was no dissection, embolus or thrombus in the coronary arteries. These findings suggest that right coronary artery vasospasm could have caused the ischemic attack, leading to lethal arrhythmias.
PMCID: PMC4905847  PMID: 26806564
coronary spastic angina; defibrillator; sudden cardiac death
3.  Ampullary Adenoma Treated by Endoscopic Double-Snare Retracting Papillectomy 
Gut and Liver  2015;9(5):689-692.
We report herein improved methods for the safe and successful completion of endoscopic papillectomy (EP). Between January 2008 and November 2011, 12 patients underwent double-snare retracting papillectomy for the treatment of lesions of the major duodenal papilla. The main outcomes were en bloc resection rates, pathological findings, and adverse events. All of the patients (mean age, 60.1 years; range, 38 to 80 years) were diagnosed with ampullary adenoma by endoscopic forceps biopsies prior to endoscopic snare papillectomy. En bloc resection by double-snare retracting papillectomy was successfully performed for all lesions (median size, 12.3 mm), comprising six tubular adenomas, one tubulovillous adenoma, three cases of epithelial atypia, one hamartomatous polyp, and one case of duodenitis with regenerative change. Significant hemorrhage and pancreatitis were observed in one case after EP. Adenoma recurrence occurred in three patients during follow-up (median, 28.5 months) at a mean interval of 2 months postoperatively (range, 1 to 3 months). No serious adverse events were observed. Double-snare retracting papillectomy is effective and feasible for treating lesions of the major duodenal papilla. Further treatment experience, including a single-arm phase II study, needs to be accumulated before conducting a randomized controlled study.
PMCID: PMC4562789  PMID: 26087781
Argon plasma coagulation; Endoscopic papillectomy; Endosonography; Intraductal ultrasonography; Tubular adenoma
4.  Discovery of DS-8108b, a Novel Orally Bioavailable Renin Inhibitor 
ACS Medicinal Chemistry Letters  2012;3(9):754-758.
A novel orally bioavailable renin inhibitor, DS-8108b (5), showing potent renin inhibitory activity and excellent in vivo efficacy is described. We report herein the synthesis and pharmacological effects of 5 including renin inhibitory activity in vitro, suppressive effects of ex vivo plasma renin activity (PRA) in cynomolgus monkey, pharmacokinetic data, and blood pressure-lowering effects in an animal model. Compound 5 demonstrated inhibitory activities toward human renin (IC50 = 0.9 nM) and human and monkey PRA (IC50 = 1.9 and 6.3 nM, respectively). Oral administration of single doses of 3 and 10 mg/kg of 5 in cynomolgus monkey on pretreatment with furosemide led to dose-dependent significant reductions in ex vivo PRA and sustained lowering of mean arterial blood pressure for more than 12 h.
PMCID: PMC4025657  PMID: 24900544
renin inhibitor; hypertension; plasma renin activity; 4-aminoadamantan-1-ol
5.  Comparison of the effects of levofloxacin on QT/QTc interval assessed in both healthy Japanese and Caucasian subjects 
There is no consensus as to what extent the results of thorough QT interval/corrected QT interval (QT/QTc) studies need to be bridged.
The results of two studies using levofloxacin in Japanese and Caucasian subjects were compared in a post hoc analysis to investigate the similarity of dose–effect responses.
Concentration–response analysis based on the change of QT interval corrected using Fridericia's formula (QTcF) from time-matched placebo was planned and performed in the combined data sets. At the geometric maximum mean concentration for the two doses in the Caucasian study, a predicted effect on QTcF comparable to the effects observed was found. For the Japanese study, the predicted effect was lower, but the difference was not statistically significant.
No statistically significant differences in QTc-prolonging effect between Japanese and Caucasian subjects were observed following levofloxacin dosing. However, a trend suggests that Caucasian subjects may be more sensitive. Age and sex did not have an impact.
PMCID: PMC3370350  PMID: 22442827
cardiac safety; clinical trial methodology; electrocardiogram; ethnic comparison; levofloxacin; pharmacology
6.  Absorption of Radionuclides from the Fukushima Nuclear Accident by a Novel Algal Strain 
PLoS ONE  2012;7(9):e44200.
Large quantities of radionuclides have leaked from the Fukushima Daiichi Nuclear Power Plant into the surrounding environment. Effective prevention of health hazards resulting from radiation exposure will require the development of efficient and economical methods for decontaminating radioactive wastewater and aquatic ecosystems. Here we describe the accumulation of water-soluble radionuclides released by nuclear reactors by a novel strain of alga. The newly discovered green microalgae, Parachlorella sp. binos (Binos) has a thick alginate-containing extracellular matrix and abundant chloroplasts. When this strain was cultured with radioiodine, a light-dependent uptake of radioiodine was observed. In dark conditions, radioiodine uptake was induced by addition of hydrogen superoxide. High-resolution secondary ion mass spectrometry (SIMS) showed a localization of accumulated iodine in the cytosol. This alga also exhibited highly efficient incorporation of the radioactive isotopes strontium and cesium in a light-independent manner. SIMS analysis showed that strontium was distributed in the extracellular matrix of Binos. Finally we also showed the ability of this strain to accumulate radioactive nuclides from water and soil samples collected from a heavily contaminated area in Fukushima. Our results demonstrate that Binos could be applied to the decontamination of iodine, strontium and cesium radioisotopes, which are most commonly encountered after nuclear reactor accidents.
PMCID: PMC3440386  PMID: 22984475
7.  Long-term bradycardia caused by atrioventricular block can remodel the canine heart to detect the histamine H1 blocker terfenadine-induced torsades de pointes arrhythmias 
British Journal of Pharmacology  2005;147(6):634-641.
Although a second-generation histamine H1 blocker terfenadine induced torsades de pointes (TdP) arrhythmias in patients via the blockade of a rapid component of delayed rectifier K+ current (IKr), such action of terfenadine has not been detected in previous animal models.We analysed the potential of the canine persistent atrioventricular block heart, a new in vivo proarrhythmia model, to detect a torsadogenic effect of terfenadine of an oral dose of 3 or 30 mg kg−1. The doses can provide therapeutic to supra-therapeutic plasma concentrations as an anti-histamine.In 2 weeks of bradycardiac heart model, there were no significant changes in any of the electrocardiogram parameters after the administration of both doses of terfenadine.In 4–6 weeks of bradycardiac heart model, the low dose of terfenadine hardly affected any of the electrocardiogram parameters except that it induced TdP in one out of six animals. The high dose significantly decreased the atrial rate and ventricular rate, prolonged the QT interval, and induced TdP in five out of six animals. Moreover, temporal variability of repolarization increased after the high-dose administration.These results suggest that long-term bradycardia caused by atrioventricular block can remodel the canine heart to detect terfenadine-induced TdP.
PMCID: PMC1751346  PMID: 16314854
Terfenadine; QT interval prolongation; torsades de pointes; chronic atrioventricular block dog
8.  Effects of Prenatal Exposure to Polychlorinated Biphenyls and Dioxins on Mental and Motor Development in Japanese Children at 6 Months of Age 
Environmental Health Perspectives  2005;114(5):773-778.
Several studies have shown that prenatal and/or postnatal background-level exposure to environmental chemicals, such as polychlorinated biphenyls (PCBs) and dioxins, induces adverse effects on the neurodevelopment of children. However, other studies have not detected any harmful influences on neurodevelopment. Furthermore, except in western countries, no developmental tests have been carried out in relation to detailed assessment of exposure to PCBs and dioxins. In this study (the Hokkaido Study on Environment and Children’s Health), the effect of prenatal exposure to background levels of PCBs and dioxins on infant neurodevelopment in Japan/Sapporo was elucidated. The associations between the total or individual isomer level of PCBs and dioxins in 134 Japanese pregnant women’s peripheral blood and the mental or motor development of their 6-month-old infants were evaluated using the second edition of the Bayley Scales of Infant Development. The mean level of total toxicity equivalency quantity (TEQ) was 18.8 (4.0–51.2) pg/g lipid in blood of 134 mothers. After adjustment for potential confounding variables, the total TEQ value was shown not to be significantly associated with mental developmental index (MDI) or psychomotor developmental index (PDI). However, the levels of one polychlorinated dibenzo-p-dioxin (PCDD) isomer, total PCDDs, and total PCDDs/polychlorinated dibenzofurans (PCDFs) were significantly negatively associated with MDI, and the levels of two PCDD isomers and three PCDF isomers were significantly negatively associated with the PDI. In conclusion, the background-level exposure of several isomers of dioxins during the prenatal period probably affects the motor development of 6-month-old infants more than it does their mental development.
PMCID: PMC1459935  PMID: 16675436
dioxins; infant development; maternal blood; polychlorinated biphenyls (PCBs); prenatal exposure

Results 1-8 (8)