What are Paracrystalline inclusions?

Paracrystalline inclusions (PCIs) They consist of stacked sheets that either run obliquely (Fig. 2A,D) or parallel (Fig. 2B,C) relative to the length of the paracrystal. Their rigidity is evidenced by their occasional deformation or rupture of membranes (Fig. 2C).

What causes mitochondrial myopathy?

Mitochondrial myopathies may be caused by mutations in the body’s nuclear DNA (the DNA found in the nucleus of cells) or by mutations or deletions in the body’s mitochondrial DNA (mtDNA, the DNA found in cells’ mitochondria).

How is mitochondrial myopathies diagnosed?

The most important of these tests is the muscle biopsy, which involves removing a small sample of muscle tissue to examine. When treated with a dye that stains mitochondria, muscles affected by mitochondrial disease often show ragged red fibers — muscle cells (fibers) that have excessive mitochondria.

What is mitochondrial ultrastructure?

Mitochondrial Ultrastructure Mitochondria are enveloped by an outer and an inner membrane enclosing a narrow intermembrane space. The outer membrane represents the border to the cytosol, and the inner membrane separates the intermembrane space from the matrix.

How many people are affected by mitochondrial myopathies?

Affected Populations Mitochondrial diseases are one of the most common forms of metabolic disease. They are estimated to affect about 1 in 5,000 people in the general population of the United States.

How is the mitochondria affected in mitochondrial myopathy?

These disorders often hamper the ability of affected cells to break down food and oxygen and produce energy. Mitochondria provide more than 90% of the energy used by the body’s tissues; mitochondrial disorders are characterized by a lack of sufficient energy for cells of the body to function properly.

What can electron microscopy tell us about mitochondrial disease pathogenesis?

In an attempt to understand the pathogenesis of mitochondrial disease, early electron microscopy investigations identified common ultrastructural abnormalities such as swelling and PCIs.

What is the pathophysiology of mitochondrial myopathy?

Introduction Mitochondrial myopathies (MM) comprise a large heterogeneous group of disorders resulting from primary dysfunction of the mitochondrial respiratory chain and causing muscle disease.

Is myasthenia gravis a mitochondrial myopathy?

A mitochondrial myopathy is a consideration in all children with exercise intolerance and ptosis or ophthalmoplegia. This combination of symptoms may also suggest myasthenia gravis. However, in myasthenia, the ocular motor features fluctuate, whereas in mitochondrial myopathies they are constant.

How is mitochondrial myopathy transmitted from mother to child?

Because the mitochondria are contributed at the time of fertilization by the maternal gamete (oocyte), mitochondrial myopathies encoded by mitochondrial genes are maternally transmitted. Myopathy is usually associated with other symptoms, usually pointing to central nervous system abnormalities.