RESUMEN
Protein kinase D (PKD) enzymes play important roles in regulating myocardial contraction, hypertrophy, and remodeling. One of the proteins phosphorylated by PKD is titin, which is involved in myofilament function. In this study, we aimed to investigate the role of PKD in cardiomyocyte function under conditions of oxidative stress. To do this, we used mice with a cardiomyocyte-specific knock-out of Prkd1, which encodes PKD1 (Prkd1loxP/loxP; αMHC-Cre; PKD1 cKO), as well as wild type littermate controls (Prkd1loxP/loxP; WT). We isolated permeabilized cardiomyocytes from PKD1 cKO mice and found that they exhibited increased passive stiffness (Fpassive), which was associated with increased oxidation of titin, but showed no change in titin ubiquitination. Additionally, the PKD1 cKO mice showed increased myofilament calcium (Ca2+) sensitivity (pCa50) and reduced maximum Ca2+-activated tension. These changes were accompanied by increased oxidation and reduced phosphorylation of the small myofilament protein cardiac myosin binding protein C (cMyBPC), as well as altered phosphorylation levels at different phosphosites in troponin I (TnI). The increased Fpassive and pCa50, and the reduced maximum Ca2+-activated tension were reversed when we treated the isolated permeabilized cardiomyocytes with reduced glutathione (GSH). This indicated that myofilament protein oxidation contributes to cardiomyocyte dysfunction. Furthermore, the PKD1 cKO mice exhibited increased oxidative stress and increased expression of pro-inflammatory markers interleukin (IL)-6, IL-18, and tumor necrosis factor alpha (TNF-α). Both oxidative stress and inflammation contributed to an increase in microtubule-associated protein 1 light chain 3 (LC3)-II levels and heat shock response by inhibiting the mammalian target of rapamycin (mTOR) in the PKD1 cKO mouse myocytes. These findings revealed a previously unknown role for PKD1 in regulating diastolic passive properties, myofilament Ca2+ sensitivity, and maximum Ca2+-activated tension under conditions of oxidative stress. Finally, we emphasized the importance of PKD1 in maintaining the balance of oxidative stress and inflammation in the context of autophagy, as well as cardiomyocyte function.
Asunto(s)
Miofibrillas , Proteína Quinasa C , Procesamiento Proteico-Postraduccional , Ratones , Animales , Conectina/metabolismo , Miofibrillas/metabolismo , Miocitos Cardíacos/metabolismo , Fosforilación , Proteínas de Microfilamentos/metabolismo , Homeostasis , Inflamación/metabolismo , Calcio/metabolismo , Mamíferos/metabolismoRESUMEN
Nanoparticles have many advantages as active materials, such as a short diffusion length, low charge transfer resistance, or a reduced probability of cracking. However, their low packing density makes them unsuitable for commercial battery applications. Hierarchically structured microparticles are synthesized from nanoscale primary particles by targeted aggregation. Due to their open accessible porosity, they retain the advantages of nanomaterials but can be packed much more densely. However, the intrinsic porosity of the secondary particles leads to limitations in processing properties and increases the overall porosity of the electrode, which must be balanced against the improved rate stability and increased lifetime. This is demonstrated for an established cathode material for lithium-ion batteries (LiNi0.33Co0.33Mn0.33O2, NCM111). For active materials with low electrical or ionic conductivity, especially post-lithium systems, hierarchically structured particles are often the only way to produce competitive electrodes.
RESUMEN
In this manuscript, we present rheology, ionic conductivity, density, chromatography, and life cycle analysis data on the PC+X electrolyte system with and without LiClO4. In particular, the data are presented in contact with Na surfaces. In this case, photographic images of electrolyte-sodium mixtures are also shown. The data was analyzed using OriginPro software to visualize it in an appropriate manner. In our view, the data serve as comparative values, form a basis of a chromatography analysis and are also valuable for modeling. The analysis of the data is presented in the manuscript "Comprehensive characterization of propylene carbonate based liquid electrolyte mixtures for sodium-ion cells" [1].
RESUMEN
For patients after bariatric surgery, diagnosis of gastric cancer is a challenge. We present a patient after Roux-en-Y gastric bypass with upper abdominal pain and abnormal computed tomography scan with diffuse wall thickening of the gastric antrum. Various biopsy techniques have been described, with surgical (laparoscopic) exploration being the most common. We were able to successfully diagnose gastric cancer in the excluded stomach by biopsy using a jejunogastrostomy, which proved to be safe and effective.