The structural correlates of 'chronic hibernating myocardium' in man consist of myocardial cells which transformed from a functional state (rich in contractile material) to a surviving state (poor in contractile material, rich in glycogen). Since the calcium-handling organelles such as SR, sarcolemma and mitochondria underwent structural changes in cells so affected, the distribution of calcium was investigated in biopsies obtained from 'hibernating' areas. The material was processed for microscopic localization of total calcium (laser microprobe mass analysis, LAMMA) and of exchangeable calcium (phosphate-pyroantimonate precipitation method, PPA). Subcellular distribution of total calcium as assessed by LAMMA revealed that in the structurally affected cells the areas in which sarcomeres were replaced by glycogen contained significantly more calcium than all other areas probed such as mitochondria, remaining sarcomeres at the cell periphery and subcellular areas of normally structured cells. Calcium precipitate, obtained after PPA assessment, was localized at the sarcolemma but was virtually absent in the mitochondria of affected cells. The high calcium content in the myolytic areas of affected cells most probably belongs to a pool of bound calcium. The observations that calcium is retained at the sarcolemma and that mitochondria are devoid of precipitate favour the hypothesis that cells structurally affected as such are not ischaemic and are still able to regulate their calcium homeostasis.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1007/BF00159123 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Chitosan-Functionalized Fluorescent Calcium Carbonate Nanoparticle Loaded with Methotrexate: Future Theranostics for Triple Negative Breast Cancer.
ACS Biomater Sci Eng
January 2025
Nano 2 Micro Material Design Lab, Department of Chemical Engineering and Technology, IIT (BHU), Varanasi 221005, India.
Herein, fluorescent calcium carbonate nanoclusters encapsulated with methotrexate (Mtx) and surface functionalized with chitosan (25 nm) (@Calmat) have been developed for the imaging and treatment of triple-negative breast cancer (TNBC). These biocompatible, pH-sensitive nanoparticles demonstrate significant potential for targeted therapy and diagnostic applications. The efficacy of nanoparticles (NPs) was evaluated in MDA-MB-231 TNBC cell lines.
View Article and Find Full Text PDFCorrelation between parathyroid adenoma volume and perioperative outcomes in primary hyperparathyroidism: Does the size matter?
Updates Surg
January 2025
University Center of Gastrointestinal and Liver Diseases-Clarunis, University of Basel, Basel, Switzerland.
Background: Primary hyperparathyroidism (PHPT) due to a parathyroid adenoma stands as one of the most prevalent endocrinological disorders, with focused parathyroidectomy being the established therapeutic strategy.
Aim: This study aims to investigate whether the volume of the pathological gland influences perioperative outcomes and postoperative morbidity.
Methods: A retrospective analysis was conducted on data from 141 patients who underwent focused parathyroidectomy for PHPT at the University Hospital of Basel between 2007 and 2022.
In-Cell Mass Spectrometry and Ultraviolet Photodissociation Navigates the Intracellular Protein Heterogeneity.
J Am Chem Soc
January 2025
State Key Laboratory of Molecular Reaction Dynamics, CAS Key Laboratory of Separation Sciences for Analytical Chemistry, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China.
Directly probing the heterogeneous conformations of intracellular proteins within their native cellular environment remains a significant challenge in mass spectrometry (MS). Here, we establish an in-cell MS and ultraviolet photodissociation (UVPD) strategy that directly ejects proteins from living cells into a mass spectrometer, followed by 193 nm UVPD for structural analysis. Applying this approach to calmodulin (CaM), we reveal that it adopts more extended conformations within living cells compared with purified samples , highlighting the unique influence of intracellular environments on protein folding.
View Article and Find Full Text PDFDistinct seasonality of nutrients in twigs and leaves of temperate trees.
Tree Physiol
January 2025
School of Natural Resources, Faculty of Geographical Science, Beijing Normal University, Beijing 100875, China.
Seasonal variations of nutrients in different organs are an essential strategy for temperate trees to maintain growth and function. The seasonal variations and variability (i.e.
View Article and Find Full Text PDFBackground: Although invasiveness is one of the major determinants of the poor glioblastoma (GBM) outcome, the mechanisms of GBM invasion are only partially understood. Among the intrinsic and environmental processes promoting cell-to-cell interaction processes, eventually driving GBM invasion, we focused on the pro-invasive role played by Extracellular Vesicles (EVs), a heterogeneous group of cell-released membranous structures containing various bioactive cargoes, which can be transferred from donor to recipient cells.
Methods: EVs isolated from patient-derived GBM cell lines and surgical aspirates were assessed for their pro-migratory competence by spheroid migration assays, calcium imaging, and PYK-2/FAK phosphorylation.
Want AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!