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carpal tunnel syndrome: damage to carpal tunnel nerve, can be due to overusephalans test is used to test for carpal tunnelwhen one nerve or nerve bundle is injured, trauma, inflammationMSMultiple sclerosis (MS) is a relatively chronic inflammatory demyelinating disorder with scarring (sclerosis) and loss of axons.Although the pathogenesis is unknown, the demyelination is thought to result from an immunogenetic-viral cause in genetically susceptible individuals. damage to myelin sheath, lesions or plaques that begin to deposit on myelin sheath on oligodendrocytes interleukin linked to it, possibly environmental Myasthenia Gravisautoimmune neuromuscular diseasebody produced antibodies against nicotinic acetylcholine receptors that are involved in muscle contractionso body cant contract and move like it shoulds and s: muscle fatigue which can be limited to small areas of bodyif it affects the diaphragm, it could lead to respiratory failureMyasthenia gravis is a disorder of voluntary muscles characterized by muscle weakness and fatigability. It is considered an autoimmune disease and is associated with an increased incidence of other autoimmune diseases.Myasthenia gravis results from a defect in nerve impulse transmission at the postsynaptic membrane of the neuromuscular junction. IgG antibody is secreted against the “self” AChR receptors and blocks the binding of acetylcholine. The antibody action destroys the receptor sites, causing decreased transmission of the nerve impulse across the neuromuscular junction.Why do antibodies contribute to the development of myasthenia gravis? Myasthenia gravis results from a defect in nerve impulse transmission at the neuromuscular junction. The postsynaptic acetylcholine receptors on the muscle cell’s membrane are no longer recognized as “self” and therefore elicit the generation of IgG antibodies produced in opposition to the acetylcholine receptors; these antibodies attach to the receptor sites and block the binding of acetylcholine. Eventually, the antibody action destroys the receptor sites. This causes diminished transmission of the nerve impulse across the neuromuscular junction and a lack of muscle depolarization. Why this autosensitization occurs is not known.Negative feedback
When one signals causes the release of another signalwhen the release of the second thing is enough, then the first signal stopsWhat is meant by a negative-feedback regulation of hormone release? Negative feedback occurs because the changing chemical, neural, or endocrine response to a stimulus negates the initiating change that triggered the release of the hormone. For example, thyroid-stimulating hormone (TSH) secretion from the anterior pituitary is stimulated by thyrotropin-releasing hormone (TRH) from the hypothalamus and by decreased serum levels of the thyroid hormones thyroxine (T4) and triiodothyronine (T3). Secretion of TSH stimulates the synthesis and secretion of thyroid hormones. Increasing levels of T