22 research outputs found
Chronic C-Type Natriuretic Peptide Infusion Attenuates Angiotensin II-Induced Myocardial Superoxide Production and Cardiac Remodeling
Myocardial oxidative stress and inflammation are key mechanisms in cardiovascular remodeling. C-type natriuretic peptide (CNP) is an endothelium-derived cardioprotective factor, although its effect on cardiac superoxide generation has not been investigated in vivo. This study tested the hypothesis that suppression of superoxide production contributes to the cardioprotective action of CNP. Angiotensin II (Ang II) or saline was continuously infused subcutaneously into mice using an osmotic minipump. Simultaneously with the initiation of Ang II treatment, mice were infused with CNP (0.05âÎŒg/kg/min) or vehicle for 2 weeks. The heart weight to tibial length ratio was significantly increased by Ang II in vehicle-treated mice. Treatment with CNP decreased Ang II-induced cardiac hypertrophy without affecting systolic blood pressure. Echocardiography showed that CNP attenuated Ang II-induced increase in wall thickness, left ventricular dilatation, and decrease in fractional shortening. CNP reduced Ang II-induced increases in cardiomyocyte size and interstitial fibrosis and suppressed hypertrophic- and fibrosis-related gene expression. Finally, CNP decreased Ang II-induced cardiac superoxide production. These changes were accompanied by suppression of NOX4 gene expression. Our data indicate that treatment with CNP attenuated Ang II-induced cardiac hypertrophy, fibrosis, and contractile dysfunction which were accompanied by reduced cardiac superoxide production
Grip strength predicts cardiac adverse events in patients with cardiac disorders: an individual patient pooled meta-analysis
Objective: Grip strength is a well-characterised measure of weakness and of poor muscle performance, but there is a lack of consensus on its prognostic implications in terms of cardiac adverse events in patients with cardiac disorders.
Methods: Articles were searched in PubMed, Cochrane Library, BioMed Central and EMBASE. The main inclusion criteria were patients with cardiac disorders (ischaemic heart disease, heart failure (HF), cardiomyopathies, valvulopathies, arrhythmias); evaluation of grip strength by handheld dynamometer; and relation between grip strength and outcomes. The endpoints of the study were cardiac death, all-cause mortality, hospital admission for HF, cerebrovascular accident (CVA) and myocardial infarction (MI). Data of interest were retrieved from the articles and after contact with authors, and then pooled in an individual patient meta-analysis. Univariate and multivariate logistic regression was performed to define predictors of outcomes.
Results: Overall, 23â480 patients were included from 7 studies. The mean age was 62.3±6.9 years and 70% were male. The mean follow-up was 2.82±1.7 years. After multivariate analysis grip strength (difference of 5âkg, 5Ă kg) emerged as an independent predictor of cardiac death (OR 0.84, 95%âCI 0.79 to 0.89, p<0.0001), all-cause death (OR 0.87, 95%âCI 0.85 to 0.89, p<0.0001) and hospital admission for HF (OR 0.88, 95%âCI 0.84 to 0.92, p<0.0001). On the contrary, we did not find any relationship between grip strength and occurrence of MI or CVA.
Conclusion: In patients with cardiac disorders, grip strength predicted cardiac death, all-cause death and hospital admission for HF.
Trial registration number: CRD42015025280
Coefficient of RâR interval variations under deep breathing load in patients with wildâtype transthyretin amyloid cardiomyopathy: A caseâcontrol study
Abstract Background and Aims An autonomic nervous disorder is an important characteristic of cardiac amyloidosis; however, the prevalence of autonomic dysfunction in wildâtype transthyretin amyloidosis (ATTRwt) has not been established. Analysis of the RâR interval coefficient of variation (CVRâR) is a noninvasive method to measure parasympathetic activity. We aimed to assess autonomic dysfunction of ATTRwt and determine the utility of CVRâR for the detection of ATTRwt in other cardiac diseases. Methods This is a singleâcenter, retrospective, caseâcontrol study. Fifty patients with heart failure (HF) were studied. The etiologies of HF were as follows: ATTRwt, nâ=â10; previous myocardial infarction (MI), nâ=â20; and left ventricular hypertrophy (LVH) due to other disease processes (e.g., aortic stenosis), nâ=â20. We measured the CVRâR at rest (CVRâRrest), CVRâR with deep breaths (CVRâRbreath), and the change rate (CVRâRdiff rate). The relative change formula is as follows: CVRâRdiff rateâ=â(CVRâRbreathâââCVRâRrest)/CVRâRrestĂ â100 (%). Results There was no difference in the CVRâRrest levels among the three groups. The CVRâRdiff rate levels in the ATTRwt group were significantly lower (ATTRwt: â8.77 [â43.8 to 10.9]; LVH: 67.4 [38.7 to 89.4]; MI: 83.7 [60.4 to 142.9]). Based on the receiver operative characteristic curve analysis to identify ATTRwt in HF, the best cutâoff value for the CVRâRdiff rate was 19.7 (area under the curve: 0.848). Conclusion Our data suggested autonomic dysfunction in patients with ATTRwt. Measurement of the CVRâR in HF patients may be a convenient support tool for the detection of ATTRwt
Expression of Let-7 family microRNAs in skin correlates negatively with severity of pulmonary hypertension in patients with systemic scleroderma
Pulmonary hypertension (PH) is a serious complication in patients with systemic scleroderma (SSc), therefore it is important to identify the factors that could predict the presence and progression of PH. Skin biopsy is performed in patients with SSc to examine the type and severity of the disease. MicroRNAs (miRNAs) are potential biomarkers for various cardiovascular diseases including PH. We determined the skin miRNA expression profile in 15 SSc patients with (n = 6) and without PH (n = 9). A mixture of equal amounts of miRNAs from PH and non-PH patients were prepared and used for miRNA PCR array analysis. The analysis identified 591 upregulated miRNAs and 57 downregulated miRNAs in the PH group. Of these, only miRNAs with a Ct value of less than 35 were subjected to further analysis. When a 1.5-fold difference was considered meaningful, 32 miRNAs were upregulated and 14 miRNAs were downregulated in the PH group. Interestingly, 5 out of 14 downregulated miRNAs belonged to the let-7 family. The results were validated by quantitative real-time PCR with specific primer for each miRNA, which showed significant downregulation of five let-7 family members (let-7a, -7d, -7e, -7f, -7g) in 6 PH compared with 9 non-PH skin samples. The expression levels of let-7d and 7b correlated negatively with pulmonary arterial pressure measured by echocardiography. The results suggest that skin miRNA is a potentially useful marker for the presence and severity of PH in patients with SSc
Expression of Let-7 family microRNAs in skin correlates negatively with severity of pulmonary hypertension in patients with systemic scleroderma
Background: Pulmonary hypertension (PH) is a serious complication in patients with systemic scleroderma (SSc), therefore it is important to identify the factors that could predict the presence and progression of PH. Skin biopsy is performed in patients with SSc to examine the type and severity of the disease. MicroRNAs (miRNAs) are potential biomarkers for various cardiovascular diseases including PH.
Methods and results: We determined the skin miRNA expression profile in 15 SSc patients with (n = 6) and without PH (n = 9). A mixture of equal amounts of miRNAs from PH and non-PH patients were prepared and used for miRNA PCR array analysis. The analysis identified 591 upregulated miRNAs and 57 downregulated miRNAs in the PH group. Of these, only miRNAs with a Ct value of less than 35 were subjected to further analysis. When a 1.5-fold difference was considered meaningful, 32 miRNAs were upregulated and 14 miRNAs were downregulated in the PH group. Interestingly, 5 out of 14 downregulated miRNAs belonged to the let-7 family. The results were validated by quantitative real-time PCR with specific primer for each miRNA, which showed significant downregulation of five let-7 family members (let-7a, -7d, -7e, -7f, -7g) in 6 PH compared with 9 non-PH skin samples. The expression levels of let-7d and 7b correlated negatively with pulmonary arterial pressure measured by echocardiography.
Conclusions: The results suggest that skin miRNA is a potentially useful marker for the presence and severity of PH in patients with SSc
Present Status of the Nd:YAG Thomson Scattering System Development for Time Evolution Measurement of Plasma Profile on Heliotron J
A new high repetition rate Nd:YAG Thomson scattering system is developed for the Heliotron J helical device. A main purpose of installing the new system is the temporal evolution measurement of a plasma profile for improved confinement physics such as the edge transport barrier (H-mode) or the internal transport barrier of the helical plasma. The system has 25 spatial points with ~10 mm resolution. Two high repetition Nd:YAG lasers (> 550 mJ@50 Hz) realize the measurement of the time evolution of the plasma profile with ~10 ms time intervals. Scattered light is collected by a large concave mirror (D = 800 mm, f/2.25) with a solid angle of ~100 mstr and transferred to interference filter polychromators by optical fiber bundles in a staircase form. The signal is amplified by newly designed fast preamplifiers with DC and AC output, which reduces the low frequency background noise. The signals are digitized with a multi-event QDC, fast gated integrators. The data acquisition is performed by a VME-based system operated by the CINOS
Doubleâchambered right ventricle complicated by hypertrophic obstructive cardiomyopathy diagnosed as Noonan syndrome
Abstract We present a case of doubleâchambered right ventricle (DCRV) complicated by hypertrophic obstructive cardiomyopathy (HOCM) in KRAS mutationâassociated Noonan syndrome. The diagnosis was incidental and made during diagnostic testing for an intradural extramedullary tumour. Spinal compression, if not surgically treated, may cause paralysis of the extremities. We decided to pursue pharmacological therapy to control biventricular obstructions and reduce the perioperative complication rate. We initiated treatment with cibenzoline and bisoprolol; the doses were titrated according to the response. After 2 weeks, the peak pressure gradient of the two RV chambers decreased from 101 to 68 mmHg, and the LV peak pressure gradient decreased from 109 to 14 mmHg. Class 1A antiarrhythmic drugs and ÎČâblockers decreased the severe pressure gradients of biventricular obstructions caused by DCRV and HOCM. The patient was able to undergo surgery to remove the intradural extramedullary tumour, which was diagnosed as schwannoma