Background: The purpose of this investigation was to characterize differential right atrial (RA) and ventricular (RV) molecular changes in Ca(2+)-handling proteins consequent to RV pressure overload and hypertrophy in two common, yet distinct models of pulmonary hypertension: dehydromonocrotaline (DMCT) toxicity and pulmonary artery (PA) banding.
Methods: A total of 18 dogs underwent sternotomy in four groups: (1) DMCT toxicity (n = 5), (2) mild PA banding over 10 wk to match the RV pressure rise with DMCT (n = 5); (3) progressive PA banding to generate severe RV overload (n = 4); and (4) sternotomy only (n = 4).
Results: In the right ventricle, with DMCT, there was no change in sarcoplasmic reticulum Ca(2+)-ATPase (SERCA) or phospholamban (PLB), but we saw a trend toward down-regulation of phosphorylated PLB at serine-16 (p[Ser-16]PLB) (P = 0.07). Similarly, with mild PA banding, there was no change in SERCA or PLB, but p(Ser-16)PLB was down-regulated by 74% (P < 0.001). With severe PA banding, there was no change in PLB, but SERCA fell by 57% and p(Ser-16)PLB fell by 67% (P < 0.001). In the right atrium, with DMCT, there were no significant changes. With both mild and severe PA banding, p(Ser-16)PLB fell (P < 0.001), but SERCA and PLB did not change.
Conclusions: Perturbations in Ca(2+)-handling proteins depend on the degree of RV pressure overload and the model used to mimic the RV effects of pulmonary hypertension. They are similar, but blunted, in the atrium compared with the ventricle.
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http://dx.doi.org/10.1016/j.jss.2012.04.066 | DOI Listing |
Biochim Biophys Acta Mol Basis Dis
January 2025
Department of Cardiology, Renmin Hospital of Wuhan University, Wuhan 430060, China; Cardiovascular Research Institute, Wuhan University, Wuhan 430060, China; Hubei Key Laboratory of Cardiology, Wuhan 430060, China. Electronic address:
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January 2025
Shandong Yankuang Intelligent Manufacturing Co., Jining, 272000, China.
The hydraulic column is a core component in the coal mine support system, however, the real-time monitoring of the hydraulic column during the service process of the hydraulic support faces challenges. To address these issues, a high-precision stress mapping method of hydraulic column is proposed. The hydraulic column loss function was constructed to guide the data-driven model training, and the cylinder stress mechanism model was established by using the elastic-plastic theory of thick-walled cylinder.
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January 2025
Cardiovascular Institute, Children's Hospital of Philadelphia, Philadelphia, PA, USA.
Heart failure with preserved ejection fraction (HFpEF) is increasingly common but its pathogenesis is poorly understood. The ability to assess genetic and pharmacologic interventions is hampered by the lack of robust preclinical mouse models of HFpEF. We developed a novel "two-hit" model, which combines obesity and insulin resistance with chronic pressure overload to recapitulate clinical features of HFpEF.
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January 2025
Key Laboratory of Targeted Intervention of Cardiovascular Disease, Collaborative Innovation Center for Cardiovascular Disease Translational Medicine, School of Basic Medical Sciences, Nanjing Medical University, Nanjing, Jiangsu, 211166, China.
Mitochondrial dysfunction is a key factor in exacerbating pressure overload-induced cardiac hypertrophy and is linked to increased morbidity and mortality. ECSIT, a crucial adaptor for inflammation and mitochondrial function, has been reported to express multiple transcripts in various species and tissues, leading to distinct protein isoforms with diverse subcellular localizations and functions. However, whether an unknown ECSIT isoform exists in cardiac cells and its potential role in regulating mitochondrial function and pathological cardiac hypertrophy has remained unclear.
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December 2024
School of Mechanical Engineering, Key Laboratory of Special Engine Technology, Ministry of Education, Nanjing University of Science and Technology, Nanjing, 210094, People's Republic of China.
In the field of gun launched missile extended range rocket, the propellant grain in the rocket needs to withstand significant launch loads during their firing phase, and also bear the high pressure caused by ignition, and the impact of launch overloads and ignition shocks on the structural integrity of propellants becomes very important. So this work investigated the dynamic initiation fracture toughness of the composite modified double-base (CMDB) propellant by both experiments and numerical simulations. The dynamic mechanical properties test of the cracked straight through flattened Brazilian disc (CSTFBD) specimens were conducted using a modified Split Hopkinson pressure bar (SHPB).
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