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Related to Nerve sheath tumor: neurofibromatosis


see nervous systemnervous system,
network of specialized tissue that controls actions and reactions of the body and its adjustment to the environment. Virtually all members of the animal kingdom have at least a rudimentary nervous system.
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the cordlike association of nerve tissues that links the brain and nerve ganglia by innervation to the other organs and tissues of the body.

A nerve primarily consists of nerve fibers. In vertebrates many nerves converge to form a bundle that is surrounded by a connective tissue sheath, the perineurium; the thin interstitial layers of connective tissue that separate the individual fibers deep within the bundle constitute the endoneurium. Finally, the entire nerve trunk, comprising several bundles, is covered by an additional sheath, the epineurium.

Nerves can be sensory (also called afferent or centripetal) or motor (also called efferent or centrifugal). Some nerves, for example, those innervating the skeletal muscles, mainly include myelinated, or medullated, fibers; others, for example, the sympathetic nerves, largely consist of unmyelinated, or unmedullated, fibers.

In reptiles, birds, mammals, and man 12 pairs of cranial nerves branch from the brain: the olfactory (cranial nerve I), the optic (cranial nerve II), the oculomotor (cranial nerve III), the trochlear (cranial nerve IV), the trigeminal (cranial nerve V), the abducent (cranial nerve VI), the facial (cranial nerve VII), the acoustic (cranial nerve VIII), the glossopharyngeal (cranial nerve IX), the vagus (cranial nerve X), the accessory (cranial nerve XI), and the hypoglossal (cranial nerve XII). Only the first ten pairs are present in fish and amphibians.

In man there are 31 pairs of spinal nerves: eight cervical, 12 thoracic, five lumbar, five sacral, and one coccygeal. Each pair innervates the effectors and receptors of a certain part of the body. The spinal nerves branch from the spinal cord into two roots—the posterior, or sensory, and the anterior, or motor. Both roots then combine to form a common trunk that consists of both sensory and motor fibers.

Several adjacent nerves can be combined into nerve plexuses, where an exchange of fibers between different nerves can take place. Three large plexuses are distinguished: the cervical, the brachial, and the lumbosacral. Each nerve plexus is the origin of several pairs of nerves; for example, the sacral portion of the lumbosacral plexus gives rise to the sciatic nerves.

Nerves that originate in the ganglia, trunks, and plexuses of the autonomic nervous system constitute a specific group. The optic nerve is remarkable for its large number of fibers; there are more than 1 million in the human optic nerve. Usually, however, there are 103 -104 fibers in a nerve. In invertebrates certain nerves are known to consist of only a few fibers. The peripheral nervous system in animals and man consists of aggregations of nerves.



A bundle of nerve fibers or processes held together by connective tissue.


Any one of the ribs of a groined vault, but esp. a rib which forms one of the sides of a compartment of the groining.


1. any of the cordlike bundles of fibres that conduct sensory or motor impulses between the brain or spinal cord and another part of the body
2. a large vein in a leaf
3. any of the veins of an insect's wing
References in periodicals archive ?
BRAFV600E mutation in sporadic and neurofibromatosis type 1-related malignant peripheral nerve sheath tumors.
Based on the histologic features and immunohistochemical results, a peripheral nerve sheath tumor was diagnosed.
Immunoprofiles of Similar Spindle Cell Neoplasms Tumor Type Myogenin Desmin SMA SC-RMS ++ ++ +/- Leiomyosarcoma - +/- ++ Low-grade myofibroblastic - +/- + sarcoma Fibrosarcoma - - +/- Malignant peripheral - - - nerve sheath tumor with rhabdomyoblastic differentiation Desmoplastic melanoma - - +/-- Tumor Type H-caldesmon S100 GFAP SC-RMS - - - Leiomyosarcoma +/- - +/-- Low-grade myofibroblastic - - - sarcoma Fibrosarcoma - - +/- Malignant peripheral - +/- - nerve sheath tumor with rhabdomyoblastic differentiation Desmoplastic melanoma - ++ +/- Abbreviations: GFAP, glial fibrillary acidic protein; SC-RMS, spindle cell rhabdomyosarcoma; SMA, smooth muscle actin; +, positive; ++, strongly positive; +/-, occasionally positive; +/--, occasionally positive, more often negative; -, negative.
Both patients and care providers are willing to participate in clinical trials for NF1 and both groups rate malignant peripheral nerve sheath tumors as the most urgent for new treatments.
Oncologic outcomes of sporadic, neurofibromatosis-associated, and radiation-induced malignant peripheral nerve sheath tumors.
Peripheral nerve sheath tumors of the gastrointestinal tract: a multicenter study of 58 patients including NF1-associated gastric schwannoma and unusual morphologic variants.
Treatment with PD0325901 reduced the abnormal growth of cells in both benign neurofibromas and malignant peripheral nerve sheath tumors (MPNSTs).
2,3) Prior reports on the percentage of malignant peripheral nerve sheath tumors (MPNST) showing MDM2 overexpression or amplification have documented variable findings.
Malignant peripheral nerve sheath tumor enhances brightly on postcontrast images and often has a central dark area secondary to necrosis and hemorrhage (Figures 3 and 4).
51 Key: NOS = not otherwise specified,; MPNST= malignant peripheral nerve sheath tumor.
Computed tomography of extracranial nerve sheath tumors with pathologic correlation.
Standard synoptic reporting currently may make sense for certain non-CNS neurologic tumors such as neuroblastoma, peripheral primitive neuroectodermal tumor, and malignant peripheral nerve sheath tumor, which behave as sarcomas, and possibly medulloblastoma.