|
Myopathies
In medicine, myopathy is a disease of the muscle in which the muscle fibers do not function properly. ''Myopathy'' means muscle disease (Greek language, Greek : myo- ''muscle'' + patheia ''pathos, -pathy'' : ''suffering''). This meaning implies that the primary defect is within the muscle, as opposed to the nerves ("neuropathies" or "neurogenic" disorders) or elsewhere (e.g., the brain). This muscular defect typically results in myalgia (muscle pain), muscle weakness (reduced muscle force), or premature muscle fatigue (initially normal, but declining muscle force). Muscle cramps, stiffness, spasm, and Muscle contracture, contracture can also be associated with myopathy. Myopathy experienced over a long period (chronic) may result in the muscle becoming an abnormal size, such as muscle atrophy (abnormally small) or a pseudoathletic appearance (abnormally large). Capture myopathy can occur in wild or captive animals, such as deer and kangaroos, and leads to morbidity and mortality. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mitochondrial Myopathy
Mitochondrial myopathies are types of myopathy, myopathies associated with mitochondrial disease. Adenosine triphosphate (Adenosine triphosphate, ATP), the chemical used to provide energy for the cell, cannot be produced sufficiently by oxidative phosphorylation when the mitochondrion is either damaged or missing necessary enzymes or transport proteins. With ATP production deficient in mitochondria, there is an over-reliance on anaerobic glycolysis which leads to lactic acidosis either at rest or exercise-induced. Primary mitochondrial myopathies are inherited, while secondary mitochondrial myopathies may be inherited (e.g. Duchenne's muscular dystrophy) or environmental (e.g. alcoholic myopathy). When it is an inherited primary disease, it is one of the Metabolic myopathy, metabolic myopathies. On biopsy, the muscle tissue of patients with these diseases usually demonstrate "ragged red" muscle fibers on Gomori trichrome staining. The ragged-red appearance is due to a buildup of a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Congenital Myopathy
Congenital myopathy is a very broad term for any muscle disorder present at birth. This defect primarily affects skeletal muscle fibres and causes muscular weakness and/or hypotonia. Congenital myopathies account for one of the top neuromuscular disorders in the world today, comprising approximately 6 in 100,000 live births every year. As a whole, congenital myopathies can be broadly classified as follows: * A distinctive abnormality in skeletal muscle fibres on the cellular level; observable via light microscope * Symptoms of muscle weakness and hypotonia * Is a congenital disorder, meaning it occurs during development and symptoms present themselves at birth or in early life. * Is a genetic disorder. Classification Myopathies with inclusion bodies and abnormal protein accumulation Congenital myopathies with inclusion bodies and protein accumulation is a broad category, and some congenital myopathies that fall within this group are well understood, such as nemaline myopathy (see ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Muscle Contracture
Muscle contractures can occur for many reasons, such as paralysis, muscular atrophy, and forms of muscular dystrophy. Fundamentally, the muscle and its tendons shorten, resulting in reduced flexibility. Various interventions can slow, stop, or even reverse muscle contractures, ranging from physical therapy to surgery. Cause Immobilization Joints are usually immobilized in a shortened position resulting in changes within the joint connective tissue, and the length of the muscle and associated tendon. Prolonged immobilization facilitates tissue proliferation which impinges on the joint space. Maintaining a shortened position for a prolonged period of time leads to: fibrous adhesion formation, loss of sarcomeres, and a loss of tissue extensibility. For example, after a fracture when immobilization is done by casting the limb in plaster of paris, the muscle length shortens because the muscle is not used for a large span of time. A common cause for having the ankle lose its f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pseudoathletic Appearance
Pseudoathletic appearance is a medical sign meaning to have the false appearance of a well-trained athlete due to pathologic causes (disease or injury) instead of true athleticism. It is also referred to as a Herculean or bodybuilder-like appearance. It may be the result of muscle inflammation (immunity-related swelling), muscle hyperplasia, muscle hypertrophy, muscle pseudohypertrophy (muscle atrophy with infiltration of fat or other tissue), or symmetrical subcutaneous (under the skin) deposits of fat or other tissue. The mechanism resulting in this sign may stay consistent or may change, while the sign itself remains. For instance, some individuals with Duchenne and Becker muscular dystrophy may start with true muscle hypertrophy, but later develop into pseudohypertrophy. In healthy individuals, resistance training and heavy manual labour creates muscle hypertrophy through signalling from mechanical stimulation ( mechanotransduction) and from sensing available energy ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Muscle Fatigue
Muscle fatigue is when muscles that were initially generating a normal amount of force, then experience a declining ability to generate force. It can be a result of vigorous exercise, but abnormal fatigue may be caused by barriers to or interference with the different stages of muscle contraction. There are two main causes of muscle fatigue: the limitations of a nerve’s ability to generate a sustained signal (neural fatigue); and the reduced ability of the muscle fiber to contract (metabolic fatigue). Muscle fatigue is not the same as muscle weakness, though weakness is an initial symptom. Despite a normal amount of force being generated at the start of activity, once muscle fatigue has set in and progressively worsens, if the individual persists in the exercise they will eventually lose their hand grip, or become unable to lift or push with their arms or legs, or become unable to maintain an isometric position (such as plank). Other symptoms may accompany such as myalgia (mu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Inflammation
Inflammation (from ) is part of the biological response of body tissues to harmful stimuli, such as pathogens, damaged cells, or irritants. The five cardinal signs are heat, pain, redness, swelling, and loss of function (Latin ''calor'', ''dolor'', ''rubor'', ''tumor'', and ''functio laesa''). Inflammation is a generic response, and therefore is considered a mechanism of innate immunity, whereas adaptive immunity is specific to each pathogen. Inflammation is a protective response involving immune cells, blood vessels, and molecular mediators. The function of inflammation is to eliminate the initial cause of cell injury, clear out damaged cells and tissues, and initiate tissue repair. Too little inflammation could lead to progressive tissue destruction by the harmful stimulus (e.g. bacteria) and compromise the survival of the organism. However inflammation can also have negative effects. Too much inflammation, in the form of chronic inflammation, is associated with variou ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Muscle Atrophy
Muscle atrophy is the loss of skeletal muscle mass. It can be caused by immobility, aging, malnutrition, medications, or a wide range of injuries or diseases that impact the musculoskeletal or nervous system. Muscle atrophy leads to muscle weakness and causes disability. Disuse causes rapid muscle atrophy and often occurs during injury or illness that requires immobilization of a limb or bed rest. Depending on the duration of disuse and the health of the individual, this may be fully reversed with activity. Malnutrition first causes fat loss but may progress to muscle atrophy in prolonged starvation and can be reversed with nutritional therapy. In contrast, cachexia is a wasting syndrome caused by an underlying disease such as cancer that causes dramatic muscle atrophy and cannot be completely reversed with nutritional therapy. Sarcopenia is age-related muscle atrophy and can be slowed by exercise. Finally, diseases of the muscles such as muscular dystrophy or myopathies can caus ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Muscular Dystrophy
Muscular dystrophies (MD) are a genetically and clinically heterogeneous group of rare neuromuscular diseases that cause progressive weakness and breakdown of skeletal muscles over time. The disorders differ as to which muscles are primarily affected, the degree of weakness, how fast they worsen, and when symptoms begin. Some types are also associated with problems in other human organs, organs. Over 30 different disorders are classified as muscular dystrophies. Of those, Duchenne muscular dystrophy (DMD) accounts for approximately 50% of cases and affects males beginning around the age of four. Other relatively common muscular dystrophies include Becker muscular dystrophy, facioscapulohumeral muscular dystrophy, and myotonic dystrophy, whereas limb–girdle muscular dystrophy and congenital muscular dystrophy are themselves groups of several – usually extremely rare – genetic disorders. Muscular dystrophies are caused by mutations in genes, usually those involved in making ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Acute (medicine)
In medicine, describing a disease as acute denotation, denotes that it is of recent wikt:onset#Noun, onset; it occasionally denotes a short wikt:duration#Noun, duration. The quantification (science), quantification of how much time constitutes "short" and "recent" varies by disease and by context, but the core denotation of "acute" is always qualitative property, qualitatively in contrast with "chronic condition, chronic", which denotes long-lasting disease (for example, in acute leukaemia and chronic leukaemia). In the context of the mass noun "acute disease", it refers to the acute phase (that is, a short course) of any disease entity. For example, in an article on ulcerative enteritis in poultry, the author says, "in acute disease there may be increased mortality rate, mortality without any obvious medical sign, signs", referring to the acute form or phase of ulcerative enteritis. Meaning variations A mild stubbed toe is an acute injury. Similarly, many acute upper respirator ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Collagen
Collagen () is the main structural protein in the extracellular matrix of the connective tissues of many animals. It is the most abundant protein in mammals, making up 25% to 35% of protein content. Amino acids are bound together to form a triple helix of elongated fibril known as a collagen helix. It is mostly found in cartilage, bones, tendons, ligaments, and skin. Vitamin C is vital for collagen synthesis. Depending on the degree of biomineralization, mineralization, collagen tissues may be rigid (bone) or compliant (tendon) or have a gradient from rigid to compliant (cartilage). Collagen is also abundant in corneas, blood vessels, the Gut (anatomy), gut, intervertebral discs, and the dentin in teeth. In muscle tissue, it serves as a major component of the endomysium. Collagen constitutes 1% to 2% of muscle tissue and 6% by weight of skeletal muscle. The fibroblast is the most common cell creating collagen in animals. Gelatin, which is used in food and industry, is collagen t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Paraneoplastic Syndrome
A paraneoplastic syndrome is a syndrome (a set of signs and symptoms) that is the consequence of a tumor in the body (usually a cancerous one). It is specifically due to the production of chemical signaling molecules (such as hormones or cytokines) by tumor cells or by an immune response against the tumor. Unlike a mass effect, it is not due to the local presence of cancer cells. Paraneoplastic syndromes are typical among middle-aged to older people, and they most commonly occur with cancers of the lung, breast, ovaries or lymphatic system (a lymphoma). Sometimes, the symptoms of paraneoplastic syndromes show before the diagnosis of a malignancy, which has been hypothesized to relate to the disease pathogenesis. In this paradigm, tumor cells express tissue-restricted antigens (e.g., neuronal proteins), triggering an anti-tumor immune response which may be partially or, rarely, completely effective in suppressing tumor growth and symptoms. Patients then come to clinical attention ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Endocrine System
The endocrine system is a messenger system in an organism comprising feedback loops of hormones that are released by internal glands directly into the circulatory system and that target and regulate distant Organ (biology), organs. In vertebrates, the hypothalamus is the neural control center for all endocrine systems. In humans, the major endocrine glands are the thyroid gland, thyroid, parathyroid gland, parathyroid, pituitary gland, pituitary, pineal gland, pineal, and adrenal glands, and the (male) testis and (female) ovaries. The hypothalamus, pancreas, and thymus also function as endocrine glands, among other functions. (The hypothalamus and pituitary glands are organs of the Neuroendocrinology#Neuroendocrine system, neuroendocrine system. One of the most important functions of the hypothalamusit is located in the brain adjacent to the pituitary glandis to link the endocrine system to the nervous system via the pituitary gland.) Other organs, such as the kidneys, also have ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
