He theorized that TNF and related proteins (cytokines), might be injuring the heart muscle.
Many types of muscular dystrophy can also reduce the efficiency of the heart muscle.
Further laboratory tests showed that this defect disrupts the calcium pump in heart muscle cells.
Some had even transformed themselves into heart muscle, beating away in over half the mouse embryos treated.
Normally, orderly waves of electric activity pass through the cardiac tissue, causing the heart muscle to contract.
They make it easier to do things like looking for blockages in the arteries that supply heart muscle.
Scientists have measured electrical signals from the beat of heart muscle cells and reconstructed the pattern on a computer.
The scientists found that people with this defect would suffer a chronic malfunction of calcium regulation in their heart muscle.
This could help scientists identify key genes for growing heart muscle and other tissues, leading to new treatments for heart failure.
They do not appear to turn into beating new heart muscle cells.
After an average of nine days, the new heart muscle cells were present in 68% of the damaged portions of the mouse hearts.
The heart muscle contracts and relaxes when calcium is released from a reservoir inside into the muscle cell and then pumped back quickly.
It is not known why the virus specifically attacks the heart muscle or why young children are particularly at risk of serious infection.
They give the heart muscle time to rest or recover and can support the failing heart until a donor heart becomes available for transplantation.
If any part of the chamber is not contracting, which may indicate an old myocardial infarction (a portion of the heart muscle is dead).
However, when poloxamer 188 was added, the cells were able to handle the stretching with no problem, in the same way as healthy heart muscle cells.
Injecting stem cells into the heart muscle carries the risk of arrhythmia, said Techung Lee, associate professor of biochemistry at the State University New York at Buffalo.
Wolfe, in contrast, grouped together a smorgasbord of heart problems that are harder to diagnose, such as angina, arrhythmia and heart failure, a weakening of the heart muscle.
The researchers also detected the creation of fresh heart muscle.
In PCI, a catheter is passed usually from the femoral artery in the groin up to the heart and into the small coronary arteries that pass through the heart muscle.
The long-term hope is to treat patients with some sort of stem cell that could turn into beating heart muscle and replace dead cardiac tissue with fully functioning new cells.
Post-mortem examination often reveals subtle, but nonetheless fatal, flaws in the heart muscle or kidneys of these animals the sorts of changes that are hard to predict and therefore almost impossible to prevent.
About four months after each patient's original operation, when their hearts had stabilised, Dr Bolli used a catheter to deliver 1m of the newly bred stem cells to their damaged heart muscle.
ECONOMIST: Stem cells and medicine: Repairing broken hearts | The
Among them are hypertrophic cardiomyopathy (HCM) - a hereditary condition in which there is excessive thickening in the heart muscle, myocarditis, which leads to inflammation of the heart muscle and coronary artery disease.
But he said it could only be used for a specific type of bypass, where an artery is open in the first portion, closed in the middle and still supplying good heart muscle.
The stress thallium and the cardio catheterization, in which dye is injected in the coronary arteries (arteries of the heart muscle) are both useful in telling us if there is any coronary artery disease.
Although the new drugs boast some advantages, Dr. Barbey says these are by no means proven, and for many the older drugs, which keep the heart muscle from tensing up too much, may be just as good.
Instead, new medical devices allow valves to be fixed or replaced with tiny catheters that are snaked up from the groin, similar to the way stents are implanted in the heart to open clogged arteries when people have heart attacks or pain from a lack of good circulation in the heart muscle.
Although some of the deaths occurred in people with underlying diseases such as atherosclerosis (and therefore could have been coincidental), government researchers who examined otherwise healthy dieters who died of ventricular arrhythmias found that the pattern of deaths suggested "the effects of protein-calorie malnutrition on the heart, " including atrophy of the heart muscle.
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