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Background Atrial fibrillation (AF), which contributes to an increased risk of stroke, frequently remains undetected, suggesting an unmet need for easier and more reliable AF screening. The reports on screening AF using an Omron blood pressure (BP) monitor with an irregular heartbeat (IHB) detector show inconsistent results, so the aim of this study was to develop a novel algorithm to accurately diagnose AF with 3 BP measurements using an Omron automated BP monitor with IHB detector.Methods and Results:In total, 303 general cardiac patients were included. Real-time single-lead ECG revealed AF in 44 patients. BP measurement was performed 3 times per patient using the Omron BP monitor HEM-907, and the number of IHBs detected was recorded. Based on these data, we developed the following algorithm: ≥1 IHB is detected during at least 2 of 3 BP measurements and the maximum number of IHBs detected is ≥2. Using this algorithm, we achieved a sensitivity of 95.5% and specificity of 96.5%, for diagnosing AF. Conclusions The novel algorithm with 3 BP measurements using the Omron automated BP monitor with IHB detector showed high sensitivity and specificity for diagnosing AF in general cardiac patients.

Adult aortic coarctation is often asymptomatic and this condition can be detected because of a murmur or unexplained hypertension. Here, we report an adult case of aortic coarctaion with heart failure and a characteristic finding of pulsation below the bilateral clavicle. A 58-year-old man with refractory heart failure due to unknown reasons was referred to our hospital. Auscultation presented no murmur and high blood pressure had been treated with medicine. Interestingly, precise physical examination revealed the bilateral pulsation at the midclavicular line from the 2nd to the 5th intercostal areas. Echographic examination revealed the dilated vessel and arterial blood flow 1–2 cm in depth from the body surface at the midclavicular 2nd intercostal areas. Contrast-enhanced computed tomography showed thoracic aortic coarctation and a well-developed collateral circulation via the bilateral internal thoracic arteries and epigastric arteries. The cause of heart failure was diagnosed as aortic coarctation. Palliative revascularization was performed and his blood pressure was lowered. When we see the patients with refractory heart failure due to unknown reasons, pulsation below the bilateral clavicle may give us a clue to diagnose the “hidden” aortic coarctation.

Many cases of human infection with the H7N9 virus have been detected in China since 2013. H7N9 viruses are maintained in chickens and are transmitted to humans at live bird markets. During circulation in birds, H7N9 viruses have accumulated amino acid substitutions in their hemagglutinin (HA), which resulted in an antigenically change in the recent H7N9 viruses. Here, we characterized 46 mouse monoclonal antibodies against the HA of the prototype strain. 16 H7-HA-specific monoclonal antibodies (mAbs) possessed hemagglutination inhibition (HI) and neutralization activities by recognizing the major antigenic site A, four other H7-HA-specific clones also showed HI and neutralizing activities via recognition of the major antigenic sites A and D, seven mAbs that reacted with several HA subtypes and possibly recognized the HA stem partially protected mice from lethal infection with prototype H7N9 virus, and the remaining 19 mAbs had neither HI nor neutralization activity. All human H7N9 viruses tested showed a similar neutralization sensitivity to the first group of 16 mAbs, whereas human H7N9 viruses isolated in 2016‒2017 were not neutralized by a second group of 4 mAbs. These results suggest that amino acid substitutions at the epitope of the second mAb group appear to be involved in the antigenic drift of the H7N9 viruses. Further analysis is required to fully understand the antigenic change in H7N9 viruses.

Background The impact of nicorandil as adjunctive therapy for percutaneous coronary intervention (PCI) in patients with ST-elevation myocardial infarction (STEMI) is controversial. We performed 15O-labeled water positron emission tomography (PET) to quantify regional myocardial perfusion in patients with STEMI who received nicorandil or no adjunctive therapy during PCI. Methods PCI was performed within 8 h after STEMI onset in 33 patients. 14 patients received intracoronary nicorandil 2 mg immediately after recanalization of the culprit lesion (Nico group). After 3–4 weeks, PET was performed in which myocardial blood flow (MBF) was measured at baseline and during adenosine triphosphate (ATP)-induced hyperemia. Myocardial vascular resistance (MVR) was calculated for all segments. Data were obtained from the reperfused (Rep) and normal segments (Cont) in each patient. Results In patients not given nicorandil (No-Nico group), the MBF was significantly lower in Rep than that in Cont at baseline and during hyperemia (Cont vs. Rep: 0.82 ± 0.14 vs. 0.68 ± 0.11, P = 0.001, ATP-Cont vs. ATP-Rep: 2.00 ± 0.72 vs. 1.52 ± 0.61, P = 0.017), which was restored in the Nico group (Cont vs. Rep: 0.79 ± 0.17 vs. 0.78 ± 0.20; ATP-Cont vs. ATP-Rep: 2.02 ± 0.84 vs. 1.84 ± 0.62). MVR was elevated in Rep at baseline and during hyperemia in the No-Nico group. MVR elevation in Rep was prevented in the Nico group. Conclusions 15O-labeled water PET was feasible for segmental analysis of MBF during the subacute phase of STEMI. It revealed that intracoronary administration of nicorandil to STEMI patients who underwent PCI prevented MVR elevation and thus restored MBF in the reperfused segments to a level similar to that in the normal segments., Highlights • 15O-labeled water positron emission tomography (PET) is a tool to compare directly reperfused segments with normal segments simultaneously in each patient's hearts. • 15O-labeled water PET permits noninvasive quantitative measurement of myocardial blood flow during the subacute phase of myocardial infarction. • 15O-labeled water PET detects restoration of myocardial blood flow after intracoronary administration of nicorandil in STEMI patients.

BACKGROUND The lipid component of coronary plaques is associated with their vulnerability. The aim of this study was to investigate which coronary risk factors were relevant in predicting serial changes in the lipid component of coronary plaques as evaluated by integrated backscatter intravascular ultrasound (IB-IVUS).Methods and Results:We enrolled 104 patients who underwent IB-IVUS-guided percutaneous coronary intervention (PCI) and were followed up with repeat IB-IVUS 6 months later. We investigated the serial changes in the plasma lipoprotein levels and the percentage of the lipid component of coronary plaques on IB-IVUS. In the multivariate linear regression analysis, the low-density lipoprotein-cholesterol/high-density lipoprotein-cholesterol (L/H) ratio independently had a significant fixed effect with the percentage of the lipid component of coronary plaques at the time of PCI. In addition, the change in the L/H ratio at the 6-month follow-up was significantly associated with that in the lipid component of coronary plaques (regression coefficient, 9.645; 95% CI: 5.814-13.475; P

For the advanced welfare service model by Yamaguchi Pre., the establishment details of welfare facilities, management form, contents of maintenance, cost and the effect on public support are examined. In case of the management by social welfare corporation, crop work, help of the volunteer activities and so on are done in addition to the fundamental service with the system which makes area and human resources reflect on the management. With the case of wooden house, there are a few plane changes and main improvement is the equipment renewal, and the effect on assistance is large for the folk association and there are a few self-burdens. Because it becomes full-scale improvement, the interior, fittings and heat insulations construction are necessary in addition to the equipment one, so the initial investment is large in case of steel frame facilities. Because there is no assistance to the steady management expenses with the model project, securing of the facilities cost of operation is difficult, in case of accepting the care insurance un-users, system-making of the human support by talented people training and public subsidy is the subject.

Excessive beta-adrenergic stimulation causes cardiac toxicity, which also contributes to cardiac oxidative stress. Although uncoupling protein 2 (UCP2), a member of the mitochondrial inner membrane carrier family, can regulate energy efficiency and oxidative stress in mitochondria, little data exist regarding interactions between UCP2 expression and beta-adrenergic stimulation induced cardiac oxidative damage. We investigated whether chronic beta-adrenergic stimulation induces myocardial energy metabolism abnormality via oxidative stress, including any role of UCP2. We also examined whether 3-methyl-1-phenyl-2-pyrazolin-5-one (MIC-186; edaravone), a potent free radical scavenger, has cardioprotective effects against beta-adrenergic stimulation. Male Sprague-Dawley rats received isoproterenol (1.2 mg/kg/day) subcutaneously or/and edaravone (30 mg/kg/day) orally. Isoproterenol increased the heart/body weight ratio, accompanied by an increase in the level of myocardial thiobarbituric acid reactive substances (TBARS) and a decreased phosphocreatine (PCr) to adenosine triphosphate (ATP) ratio. Isoproterenol also markedly increased expressions of UCP2 mRNA (1.74 fold vs. non-isoproterenol) and protein (1.93 fold vs. non-isoproterenol). Edaravone had no apparent effect in hypertrophic responses, but significantly prevented both increases in TBARS and decreases in the PCr/ATP ratio. Edaravone also prevented increases in UCP2 mRNA (0.76 fold vs. isoproterenol) and protein (0.62 fold vs. isoproterenol) expressions against isoproterenol administration. Our results suggest that chronic beta-adrenergic stimulation induces myocardial energy inefficiency via excessive oxidative stress. The antioxidant effect of edaravone has potential to improve energy metabolism abnormalities against beta-adrenergic stimulation. Adequate regulation of UCP2 expression through artificial reduction of oxidative stress may play an important role in protection of the myocardial energy metabolism.

Background— Because the mechanism of the angiogenic property of nitric oxide (NO) was not fully understood in vivo, we focused on the role of vascular endothelial growth factor (VEGF) in angiogenesis induced by endothelial NO synthase (eNOS) gene transfer. Methods and Results— After intramuscular injection of eNOS DNA into a rat ischemic hindlimb, transfection of eNOS vector resulted in a significant increase in eNOS protein 1 week after transfection. In addition, tissue concentrations of nitrite and nitrate were significantly increased in rats transfected with the eNOS gene up to 2 weeks after transfection. The increase in tissue nitrite and nitrate concentrations was completely inhibited by N G -nitro- l -arginine methyl ester (L-NAME). In contrast, serum concentrations of nitrite and nitrate and blood pressure were not changed by eNOS gene transfer. Importantly, overexpression of the eNOS gene resulted in a significant increase in peripheral blood flow, whereas L-NAME inhibited the increase in blood flow. Interestingly, basal blood flow was significantly lower in rats treated with L-NAME than in control rats. A significant increase in capillary number was consistently detected in rats transfected with the eNOS gene at 4 weeks after transfection, accompanied by a significant increase in VEGF. Moreover, administration of neutralizing anti-VEGF antibody abolished the increase in blood flow and capillary density induced by eNOS plasmid injection. Conclusions— Overall, intramuscular injection of bovine eNOS plasmid induced therapeutic angiogenesis in a rat ischemic hindlimb model, a potential therapy for peripheral arterial disease. The stimulation of angiogenesis by NO might be due to upregulation of local VEGF expression.

The purpose of this paper is that firstly the problem for making knowledge-intensive of the construction industry is examined, and then the contract form and risk management in putting especially is focused. It is required to be based for making knowledge-intensive, because this makes the construction industry develop itself and can contribute to the society.To begin with, the fundamental problem for evolving to the knowledge-intensive construction industry is examined. Here, the actual situation of the construction industry from the viewpoint of the knowledge-intensive side is outlined, and next, the fundamental problem for evolving to knowledge-intensive is examined and is extracted.From the inside of the fundamental problem, “contract form and risk management” is taken up as one in which the priority is the highest for making knowledge-intensive.

Uncoupling proteins, inner mitochondrial membrane proton transporters, are important for regulating myocardial energy efficiency. We investigated the effects of the ACE inhibitor perindopril on cardiac performance, myocardial energy efficiency, and uncoupling protein expression in an aortic regurgitation rat model. Twenty male Sprague-Dawley rats, in which aortic regurgitation was produced, were divided into untreated and perindopril-treated (5 mg · kg −1 · d −1 ) rats. The treatments were initiated 3 days after operation. Ten control rats were sham-operated. Measurements of blood pressure and echocardiography were repeated before and 100 days after operation (endpoint). Left ventricular uncoupling protein-2 expression, creatine phosphate, and adenosine triphosphate were measured at endpoint. In perindopril-treated rats, systolic and diastolic blood pressure decreased after treatment (92±4/65±2 mm Hg). At endpoint, left ventricular end-diastolic dimension in untreated (10.7±0.2 mm) and treated rats (9.2±0.2 mm) was increased, and fractional shortening was reduced in untreated rats (28±1%) but did not change in treated rats (36±2%). Uncoupling protein-2 mRNA expression increased in untreated rats (3.7-fold) and was suppressed by perindopril (1.5-fold). The creatine phosphate was reduced in untreated rats (10.6±0.7 μmol/g) but not in treated rats (15.9±2.0 μmol/g). In the chronic stage of aortic regurgitation, perindopril improved cardiac performance and myocardial energy efficiency, in which the suppression of uncoupling protein-2 may play an important role.

We tested the hypothesis that pioglitazone (insulin sensitizer) reduces oxidative stress and improves aortic wall distensibility in the pre-diabetic stage of Otsuka Long-Evans Tokushima Fatty rats, type 2 diabetes mellitus (DM) model. 20 DM and 9 nonDM male rats were divided into 3 groups: treated-DM, untreated-DM, and untreated-nonDM. Pioglitazone (0.01%) was mixed in chow in the treated group from 15 to 20 weeks of age. At baseline and 20 weeks, plasma malondialdehyde (MDA) was measured. At 20 weeks, intravascular ultrasound images and aortic pressure were simultaneously recorded. Stiffness parameter beta was calculated from the cyclic variations of aortic diameter and pressure. From an excised thoracic aorta, aortic wall collagen was measured, and the morphology was histopathologically evaluated by hematoxylin-eosin staining. At 20 weeks, MDA (nmol/ml) in treated-DM (2.3 +/- 0.3) was lower than in untreated-DM (3.2 +/- 0.6, p < 0.0001). beta in treated-DM (0.53 +/- 0.21) was smaller than that in untreated-DM (0.88 +/- 0.26, p = 0.0067). Aortic wall collagen (mg/100 mg dry weight) did not decrease in treated-DM (22.3 +/- 3.2 vs untreated-DM : 19.6 +/- 4.7). Lumen/medial area ratio (L/M) increased in treated-DM (2.79 +/- 0.40 vs untreated-DM : 2.22 +/- 0.20, p = 0.0041, untreated-nonDM : 2.25 +/- 0.55, p = 0.0075). MDA was significantly correlated with beta (r = 0.65, p = 0.0005) or L/M (r = -0.60, p = 0.0008). Pioglitazone may reduce oxidative stress and contribute to improvement of aortic wall stiffness without decrease in collagen content at an early prediabetic stage of type 2 DM.

Regulatory T cells (Tregs) play a crucial role in the negative regulation of immune responses. Recent studies suggest that Tregs are involved in the pathogenesis of atherosclerosis and myocarditis. Here, we investigated the involvement of Tregs on worsening heart failure (HF) in patients with reduced ejection fraction (HF-REF). The study population consisted of 32 HF-REF patients who were hospitalized for worsening HF, and 18 control subjects. Cardiac function was evaluated by echocardiography. A single venous blood sample was collected before discharge. Circulating T cells were evaluated by flow cytometry. Tregs were defined as CD4(+)CD25(+)Foxp3(+)T cells, and the correlations between the frequency of Tregs and CRP, IL-6 and several echoparameters were analysed. Furthermore, all HF-REF patients were followed up to 12 months from discharge to examine the predictors of recurrent hospitalization.In HF-REF patients, Tregs were significantly decreased (5.9 ± 1.4 versus 8.0 ± 2.2%, P < 0.01), while CD4(+)HLADR(+)T cells were increased (10.1 ± 5.4 versus 7.3 ± 3.1%, P < 0.05), compared with controls. Tregs were negatively correlated with left ventricular end-diastolic dimension, and levels of CRP and IL-6. Eleven of 32 HF-REF patients were rehospitalized for worsening HF within 12 months. Multivariate Cox regression analysis showed that CD4/CD8 and frequency of Tregs were independent predictors for recurrent hospitalization. Furthermore, HF-REF patients expressing under 6% Treg/CD4(+)T cells showed a significantly higher incidence of recurrent hospitalization for worsening HF within 12 months.Our data suggest that Tregs might be involved in the pathogenesis of decompensated HF, and may be a novel predictor of poor prognosis in HF-REF patients.

Five phenolic compounds, p-hydroxyacetophenone, 5,7-dihydroxychromone, naringenin, quercetin, and iso-americanol A, were found first time in the barley tea, together with the known compounds, p-hydroxybenzaldehyde, 3,4-dihydroxybenzaldehyde, p-hydroxybenzoic acid, vanillic acid, and p-coumaric acid. The anti-oxidative properties were evaluated by measuring their peroxynitrite-scavenging activities. Among these compounds, 3,4-dihydroxybenzaldehyde, p-coumaric acid, quercetin, and isoamericanol A showed stronger activities than that of BHT (butylated hydroxytoluene) at 400 microM.

(+/-)-5,5'-Dimethoxysesamin, erythrinasinate, indole-3-carbaldehyde, (7R,8S)-dihydrodehydrodiconiferyl alcohol 9-O-beta-D-glucopyranoside, cis- and trans-N-(p-coumaroyl)serotonin, serotonin, 3,4-dihydroxybenzoic acid, and 3,4-dihydroxybenzaldehyde have been found in tobiko, a food by-product, and evaluation of their peroxynitrite scavenging activities has been done. Among these compounds, serotonin, trans-N-(p-coumaroyl)serotonin, 3,4-dihydroxybenzaldehyde, and 3,4-dihydroxybenzoic acid showed stronger activities than that of BHT (butylated hydroxytoluene) at 200 microM.

Heart failure has been divided into heart failure with preserved left ventricular (LV) ejection fraction (EF) and heart failure with reduced EF, because the pathophysiologies of the two conditions are different. Cardio-ankle vascular index (CAVI) is a new indicator of arterial stiffness, and the most conspicuous feature of CAVI is its independence of blood pressure at the time of measurement. Arterial stiffness has been considered to increase LV afterload, which requires special care to avoid the onset of heart failure. We compared the correlation of arterial stiffness as assessed by CAVI to LV function in 44 hypertensive patients with preserved EF (EF: 71 ± 7%) and 31 patients with reduced EF (48 ± 8%). All of patients with reduced EF had history of both hypertension and myocardial infarction. Using Doppler echocardiography, LV diastolic and systolic function was evaluated by measuring peak early diastolic mitral annular velocity (e') and global LV peak systolic longitudinal strain (GPSLS), respectively. In patients with preserved EF, CAVI was correlated with e' (r = -0.313, p = 0.038), but not with GPSLS (r = 0.207). By contrast, CAVI was correlated with GPSLS (r = 0.604, p0.001) as well as e' (r = -0.393, p = 0.029) in patients with reduced EF. Thus, patients with reduced EF showed a closer correlation of arterial stiffness to LV function compared with patients with preserved EF. Therefore, hypertensive patients with reduced EF require a stricter regimen for treating arterial stiffness than their counterparts with preserved EF.

SPECIFIC AIMSMyocardial mitochondrial energy metabolism in heart failure is still controversial. We focused on serial changes in the cardiac performance and adenosine triphosphate (ATP) biosynthesi...

Objective We investigated the contribution of reduced nicotinamide-adenine dinucleotide phosphate (NADPH) oxidase-dependent reactive oxygen species (ROS) generation to the pathogenesis of diastolic heart failure (DHF) in Dahl salt-sensitive (DS) hypertensive rats, with the aim of testing our hypothesis that the cardioprotective effects of angiotensin II (Ang II) blockade are provided by the suppression of this pathway. Methods DS rats were maintained on high (H: 8.0% NaCl) or low (L: 0.3% NaCl) salt diets from age 7 to 17 weeks. DS/H rats were also treated with candesartan cilexetil (10 mg/kg per day, orally) or a superoxide dismutase mimetic, tempol (3 mmol/l in drinking water) from age 7 to 17 weeks. Results DS/H rats represented hypertension, left ventricular (LV) relaxation abnormality and myocardial stiffening with preserved systolic heart function. As compared with DS/L rats, DS/H rats showed higher levels of transforming growth factor-beta (TGF-beta), connective tissue growth factor (CTGF), p22phox and gp91phox mRNA expression, NADPH oxidase activity and thiobarbituric acid-reactive substance (TBARS) contents in LV tissues. Gene expression of uncoupling protein-2 (UCP-2), an inner mitochondrial membrane proton transporter, was also 2.8 +/- 0.5-fold higher. In DS/H rats, treatment with candesartan did not alter blood pressure, but resulted in a marked improvement of the hemodynamic deterioration; these therapeutic effects were accompanied by decreases in myocardial NADPH oxidase activity, TBARS contents and the expression of TGF-beta, CTGF, p22phox, gp91phox and UCP-2. Similar therapeutic effects were provided by treatment with tempol in DS/H rats. Conclusions Our data suggest that NADPH oxidase-mediated ROS production contributes to the pathogenesis of DHF in DS hypertensive rats, and that the cardioprotective effects of AngII blockade are, at least partially, mediated through the suppression of this pathway.

Left ventricular (LV) dilatation following myocardial infarction (MI) is a major determinant of the patient’s prognosis, and myocardial energy metabolism may play a key role in LV remodeling. We aimed to investigate the relative timing of LV dilatation to LV function, myocardial energy regulation by uncoupling protein (UCP)-2, and cellular damage in the noninfarct zone. Myocardial infarction was produced in Sprague-Dawley rats by ligation of the coronary artery. The LV end-diastolic dimension (mm) increased (8.9 ± 0.3 vs 6.8 ± 0.8 in sham-operated rats, P < 0.01) in association with elevation of the LV end-diastolic pressure (mmHg) (18 ± 5 vs 6 ± 2 in sham-operated rats) at 1 week following the ligation. At 4 weeks, the UCP-2 expression (180% of that in sham-operated rats) and LV end-diastolic dimension increased further (11.1 ± 0.5, P < 0.01) but there was no change in the LV end-diastolic pressure. The mechanisms for LV dilatation were quite different between the early and late stages after MI. In the late stage, augmentation of UCP-2 expression in the noninfarct zone may be related to the LV dilatation. Further examinations regarding the possibility of the protective role of UCP-2 are needed.

We tested the hypothesis that pioglitazone (insulin sensitizer) reduces oxidative stress and improves aortic wall distensibility in the pre-diabetic stage of Otsuka Long-Evans Tokushima Fatty rats, type 2 diabetes mellitus (DM) model. 20 DM and 9 nonDM male rats were divided into 3 groups: treated-DM, untreated-DM, and untreated-nonDM. Pioglitazone (0.01%) was mixed in chow in the treated group from 15 to 20 weeks of age. At baseline and 20 weeks, plasma malondialdehyde (MDA) was measured. At 20 weeks, intravascular ultrasound images and aortic pressure were simultaneously recorded. Stiffness parameter beta was calculated from the cyclic variations of aortic diameter and pressure. From an excised thoracic aorta, aortic wall collagen was measured, and the morphology was histopathologically evaluated by hematoxylin-eosin staining. At 20 weeks, MDA (nmol/ml) in treated-DM (2.3 +/- 0.3) was lower than in untreated-DM (3.2 +/- 0.6, p0.0001). beta in treated-DM (0.53 +/- 0.21) was smaller than that in untreated-DM (0.88 +/- 0.26, p = 0.0067). Aortic wall collagen (mg/100 mg dry weight) did not decrease in treated-DM (22.3 +/- 3.2 vs untreated-DM : 19.6 +/- 4.7). Lumen/medial area ratio (L/M) increased in treated-DM (2.79 +/- 0.40 vs untreated-DM : 2.22 +/- 0.20, p = 0.0041, untreated-nonDM : 2.25 +/- 0.55, p = 0.0075). MDA was significantly correlated with beta (r = 0.65, p = 0.0005) or L/M (r = -0.60, p = 0.0008). Pioglitazone may reduce oxidative stress and contribute to improvement of aortic wall stiffness without decrease in collagen content at an early prediabetic stage of type 2 DM.

There is considerable evidence to indicate that humoral factors play an important role in the development of left ventricular hypertrophy. Cardiotrophin-1 (CT-1) is a cytokine that has been shown to induce cardiac hypertrophy in a dose-dependent manner. The aim of the present study was to investigate the acute effect of CT-1 on hemodynamic parameters in spontaneously hypertensive rats (SHR) and Wistar Kyoto rats (WKY) and to study the relationship between the plasma concentration of CT-1 and its hemodynamic effect. Ten-week-old SHR and age-matched WKY were used. Blood pressure (BP), heart rate (HR) and plasma concentration of CT-1 were measured both before and for 60 min after intravenous bolus injection of human CT-1 (10 microg/kg). CT-1 injection significantly decreased BP and significantly increased HR in SHR and WKY. There were significant differences in BP and HR between the two groups at all time points after injection. The lowest BP, highest HR and maximal plasma concentrations of CT-1 were observed in both groups within 10 min after injection. However, after converting the values into the percentage change from their respective baselines, there were no significant differences between the two groups in BP or HR at any time point. There was also no significant difference between the two groups at any time point in the plasma concentration of CT-1. This study indicates that CT-1 decreases BP and increases HR in both SHR and WKY. The most obvious change occurred within 10 min after injection. However, there was no significant difference in the hypotensive effect of CT-1 on 10-week-old SHR and WKY.

This study investigated the effect of pioglitazone, an insulin sensitizer, on metabolic abnormalities and oxidative stress as a cause of myocardial collagen accumulation in prediabetic rat hearts. Twenty male diabetic rats and 9 male nondiabetic age-matched rats were used. The diabetic rats were divided into two groups: diabetic treated and untreated. Pioglitazone was mixed in rat chow fed to the diabetic treated group (0.01%). Treatment duration was 5 weeks. At baseline (15 weeks) and 20 weeks of age, blood glucose, lipid, insulin, and plasma malondialdehyde-thiobarbituric acid (MDA) levels were measured and Doppler echocardiography was tracked. At 20 weeks of age, left ventricular collagen content was studied. Blood glucose, plasma insulin, and triglyceride levels in the diabetic treated group were significantly lower than those in the untreated diabetic group. Deceleration time (ms) of early diastolic inflow in the treated diabetic group decreased significantly compared with the untreated diabetic group (65 +/- 8 vs. 77 +/- 8, p < 0.01). Ratio of left ventricular weight to body weight (mg/g) and ratio of left ventricular collagen content to dry weight (mg/100 mg) were decreased in the treated diabetic group (1.5 +/- 0.1, 1.3 +/- 0.3) compared with the untreated diabetic group (1.7 +/- 0.2, p < 0.01; 1.7 +/- 0.3, p < 0.05). Plasma MDA concentration (nmol/ml) significantly decreased (2.9 +/- 0.3 at baseline to 2.3 +/- 0.3 at 20 weeks, p = 0.001) in the treated diabetic group, and was lower than that in the untreated diabetic group (3.2 +/- 0.7 at 20 weeks, p < 0.05). Pioglitazone improved glucose and lipid metabolism and reduced oxidative stress in the left ventricle, which decreased left ventricular collagen accumulation and improved left ventricular diastolic function of prediabetic rat hearts.

Troglitazone, an oral antidiabetic agent, has hypoglycemic effects in insulin-resistant animal models and humans. This study was conducted to evaluate its effect on left ventricular diastolic dynamics of a spontaneous diabetic (DM) rat model. Twenty DM rats and 20 age-matched nonDM rats were used, and 10 of each group were treated with troglitazone as a 0.2% food admixture for 10 weeks. At 5 and 15 weeks of age, Doppler echocardiography and M-mode echocardiography were performed. Troglitazone treatment significantly improved the left ventricular diastolic dynamics of DM rats: deceleration time (msec) of early diastolic inflow decreased significantly (treated 52 ±3 vs untreated 64 ±5, p = 0.0002), and peak velocity of early transmitral inflow (cm/sec) increased significantly (treated 96 ±7 vs untreated 86 ±8, p = 0.0216). The data suggest that troglitazone improves left ventricular diastolic dynamics of a DM rat model at prediabetic stage.

This study investigated the effect of the angiotensin-converting enzyme (ACE) inhibitor perindopril on left ventricular (LV) remodeling and cardiac function in rats with aortic regurgitation (AR). Twenty male Sprague-Dawley rats in which AR was produced by closed-chest aortic valve puncture were divided into untreated and perindopril-treated (5 mg/kg/day) rats. Ten control rats were sham-operated. Blood pressure, body weight, and echocardiographic recordings were followed every 2 weeks for a period of 12 weeks. LV dimension (LVD) and fractional shortening (FS) were calculated. The heart was finally excised for weight, hydroxyproline measurements, and histopathology. At 12 weeks, end-diastolic LVD increased in untreated rats (10.8 +/- 0.2 mm) but did not dilate in treated rats (9.6 +/- 0.3 mm, p < 0.01 vs untreated rats). FS decreased from 6 weeks in untreated rats (27.3 +/- 0.9% at 12 weeks), but did not change in treated rats (33.8 +/- 0.5%, p < 0.001). The ratio of LV weight to body weight in untreated rats (2.62 +/- 0.11 mg/g, p < 0.05) was higher than in sham-operated rats (1.52 +/- 0.02 mg/g) and than in treated rats (1.95 +/- 0.07 mg/g). Interstitial collagen accumulation histopathologically increased in untreated rats and was inhibited in treated rats. LV collagen of untreated rats (1.46 +/- 0.08 mg/100 mg, p = 0.03) was higher than those of treated (1.08 +/- 0.09 mg/100 mg) and sham-operated rats (1.06 +/- 0.14 mg/100 mg). Perindopril inhibited LV remodeling induced by volume overload and preserved LV function in AR rats.

The purpose of our study has to determine the myocardial protective effects of the angiotensin-converting enzyme (ACE) inhibitor temocapril (TEM, 7 mg/kg/day) simultaneously administered with doxorubicin (Adriamycin). Twenty male Sprague-Dawley rats were intraperitoneally administered a cumulative dose of 15 mg/kg of doxorubicin (each dose of 1.0 mg/kg x 15) for 3 weeks, and divided into TEM-untreated and -treated rats. Seven control rats were injected with saline intraperitoneally. Body weight, hemodynamics, and echocardiographic measurements including quantitative analysis of ultrasonic integrated backscatter (IB) were obtained for 12 weeks after treatment. Finally, rats were killed for histopathologic study. At 6 weeks, end-diastolic left ventricular diameter (LVD) and percentage fractional shortening (%FS) were similar in TEM-treated and TEM-untreated rats, but cyclic variation of IB (dB) significantly decreased in TEM-untreated rats (7.3 +/- 1.2; control rats, 9.7 +/- 0.9; p < 0.01). At 12 weeks, %FS decreased in TEM-untreated rats (26.1 +/- 6.1%: TEM-treated rats, 34.2 +/- 6.2; p < 0.05), and calibrated IB (dB) in TEM-untreated rats (15.5 +/- 0.5) increased as compared with that in TEM-treated rats (12.1 +/- 0.7; p < 0.01). Interstitial collagen accumulation increased in TEM-untreated rats and was inhibited in treated rats. Simultaneous administration of TEM with doxorubicin was beneficial in preventing doxorubicin-induced myocardial damage, and myocardial tissue characterization was useful for the early detection of myocardial damage and the assessment of therapy.