Search results for " Muscle"
showing 10 items of 1495 documents
Dibutyryl cyclic AMP and adrenaline increase contractile force and 45Ca uptake in mammalian cardiac muscle
1973
The effects of dibutyryl cyclic AMP (DB-AMP; 10−3M) and adrenaline (2.2×10−6 M) on contractile force, 45Ca uptake, and total myocardial Ca concentration were investigated in electrically driven left auricles isolated from rat hearts. The experiments were performed at an extracellular Ca concentration of 0.45 mM and at low frequency of stimulation (15 beats/min). 45Ca exposure was 5 min. Under the conditions used, both drugs increased contractile force and enhanced 45Ca uptake (expressed as relative specific activity) by about 30% (DB-AMP) and 40% (adrenaline), respectively. Thus, the results provide evidence that the effects of adrenaline on 45Ca uptake in mammalian cardiac muscle can be mi…
Muscle repair after physiological damage relies on nuclear migration for cellular reconstruction
2021
Muscle repair without stem cells Skeletal muscle is a mechanical organ that endures cellular damage after contraction. Lesions caused by external injury can be repaired by muscle stem cells, which fuse with injured cells or create entirely new myofibers. Roman et al . describe a cell-autonomous repair process that is independent of muscle stem cells (see the Perspective by McNally and Demonbreun). After localized damage, myonuclei migrate to injury sites and locally deliver messenger RNA for cellular reconstruction. This myofiber self-repair represents a model for understanding the restoration of muscle architecture in health and disease. —BAP
Gli Angiomi Primitivi Dei Muscoli Striati
1957
Starting from a personal observation of primary angioma of the left pectoralis major, investigations on muscle angiomas are resumed, with the purpose of completing the latest statistical analyses. 75 new cases are reviewed which, added to those from Shallow, Eger and Wagner, bring the number of angiomas referred in the literature up to 111. The etiopathogenesis, pathological anatomy and symptomatology of this affection are considererd and the differential diagnosis, still very difficult, is discussed. A diagnostical misunderstanding may be avoided or limited by thinking of this possible occurrence. The numerous means, currently available for an easier diagnosis are exposed, like direct roe…
Importance of Sniff Nasal Pressure (SNIP) as predictor of nocturnal respiratory function in amyotrophic lateral sclerosis (ALS)
2019
Background: In ALS, respiratory disturbances during sleep have an important role in the natural history of the disease. Diurnal and nocturnal blood gases are weakly correlated, but nocturnal respiratory disorders are difficult to predict. Aim: To evaluate if SNIP, an important parameter reflecting respiratory muscle strength, is related to nocturnal respiratory disorders and whether it contributes to predict nocturnal blood gas alterations in addition to daytime blood gas levels in ALS. Methods: Forty patients with ALS, after a daytime respiratory function evaluation, including arterial blood gases and SNIP, underwent a polysomnography with transcutaneous capnography (tcPCO2). The patients …
Exercise-based cardiac rehabilitation
2020
Abstract Exercise-based cardiac rehabilitation (CR) is well-documented and justified integral part of disease management in stable coronary heart disease patients. CR programs are defined as multifactorial and comprehensive, with physical activity counseling and exercise training as key components in all rehabilitation and preventive interventions. The physiological and clinical benefits of exercise-based CR are widely established with similar benefits for women and men and advanced aged patients as well. In patients with cardiovascular disease, exercise-based CR elicits favorable effects on the cardiac function, endothelium and skeletal muscle resulting to an improvement of quality of life…
Biomaterials and bioactive molecules to drive differentiation in striated muscle tissue engineering
2014
Tissue engineering is an innovative, multidisciplinary approach which combines (bio)materials, cells and growth factors with the aim to obtain neo-organogenesis to repair or replenish damaged tissues and organs. The generation of engineered tissues and organs (e. g. skin and bladder) has entered into the clinical practice in response to the chronic lack of organ donors. In particular, for the skeletal and cardiac muscles the translational potential of tissue engineering approaches has clearly been shown, even though the construction of this tissue lags behind others given the hierarchical, highly organized architecture of striated muscles. Cardiovascular disease is the leading cause of deat…
Altered expression of inflammation-related genes in human carotid atherosclerotic plaques.
2011
Abstract Objective Inflammation is a pivotal process in atherosclerosis development and progression, but the underlying molecular mechanisms remain largely obscure. We have conducted an extensive expression study of atherosclerotic plaques to identify the inflammatory pathways involved in atherosclerosis. Methods We studied 11 human carotid plaques, their respective adjacent regions and 7 control arteries from different subjects. Expression of 92 genes was studied by TaqMan low-density array human inflammation panel. Human aortic endothelial and smooth muscle cells were used for in vitro experiments. Results The mRNA levels of 44/92 genes (48%) differed significantly between the tissues exa…
Glycogen phosphorylase in fish muscle: demonstration of three interconvertible forms
1990
White skeletal muscle of crucian carp contains a single isoenzyme of glycogen phosphorylase, which was purified approximately 300-fold to a specific activity of approximately 13 mumol.min-1.mg protein-1 (assayed in the direction of glycogen breakdown at 25 degrees C). Tissue extracts of crucian muscle produced three distinct peaks of phosphorylase activity when separated on DEAE-Sephacel. Peaks 1 and 3 were identified, in terms of kinetic properties and by interconversion experiments, as phosphorylase b and a, respectively. Peak 2 was shown to be a phospho-dephospho hybrid. The three interconvertible forms of phosphorylase were purified and shown to be dimeric molecules at 20 degrees C. At …
Protein targeting to the plasma membrane of adult skeletal muscle fiber: an organized mosaic of functional domains.
2001
The plasma membrane of differentiated skeletal muscle fibers comprises the sarcolemma, the transverse (T) tubule network, and the neuromuscular and muscle-tendon junctions. We analyzed the organization of these domains in relation to defined surface markers, beta-dystroglycan, dystrophin, and caveolin-3. These markers were shown to exhibit highly organized arrays along the length of the fiber. Caveolin-3 and beta-dystroglycan/dystrophin showed distinct, but to some extent overlapping, labeling patterns and both markers left transverse tubule openings clear. This labeling pattern revealed microdomains over the entire plasma membrane with the exception of the neuromuscular and muscle-tendon j…
Toll-like receptor 3 mediates expression of clusterin/apolipoprotein J in vascular smooth muscle cells stimulated with RNA released from necrotic cel…
2010
Clusterin/Apolipoprotein J is a protein that is upregulated in a broad spectrum of diverse pathological processes. The predominant form is a secreted glycoprotein (sCLU) with cytoprotective and anti-inflammatory properties which shows enhanced expression in vascular smooth muscle cells (VSMC) following aortic injury and in atherosclerotic disease. Recent evidence indicates that during atherosclerosis, Toll-like receptors (TLRs) are activated in vascular cells by endogenous ligands. Here, we analyzed whether CLU expression in VSMC is controlled by TLRs, and stimulated by factors associated with or released by necrotic cells. Activation of TLR3 by the synthetic RNA analogue polyinosinic-polyc…