Hu Paraneoplastic Encephalomyelitis Antigens: A family of RNA-binding proteins that are homologues of ELAV protein, Drosophila. They were initially identified in humans as the targets of autoantibodies in patients with PARANEOPLASTIC ENCEPHALOMYELITIS. They are thought to regulate GENE EXPRESSION at the post-transcriptional level.Paraneoplastic Syndromes, Nervous System: Degenerative or inflammatory conditions affecting the central or peripheral nervous system that develop in association with a systemic neoplasm without direct invasion by tumor. They may be associated with circulating antibodies that react with the affected neural tissue. (Intern Med 1996 Dec;35(12):925-9)Paraneoplastic Syndromes: In patients with neoplastic diseases a wide variety of clinical pictures which are indirect and usually remote effects produced by tumor cell metabolites or other products.Paraneoplastic Polyneuropathy: A diffuse or multifocal peripheral neuropathy related to the remote effects of a neoplasm, most often carcinoma or lymphoma. Pathologically, there are inflammatory changes in peripheral nerves. The most common clinical presentation is a symmetric distal mixed sensorimotor polyneuropathy. (Adams et al., Principles of Neurology, 6th ed, p1334)Encephalomyelitis, Autoimmune, Experimental: An experimental animal model for central nervous system demyelinating disease. Inoculation with a white matter emulsion combined with FREUND'S ADJUVANT, myelin basic protein, or purified central myelin triggers a T cell-mediated immune response directed towards central myelin. The pathologic features are similar to MULTIPLE SCLEROSIS, including perivascular and periventricular foci of inflammation and demyelination. Subpial demyelination underlying meningeal infiltrations also occurs, which is also a feature of ENCEPHALOMYELITIS, ACUTE DISSEMINATED. Passive immunization with T-cells from an afflicted animal to a normal animal also induces this condition. (From Immunol Res 1998;17(1-2):217-27; Raine CS, Textbook of Neuropathology, 2nd ed, p604-5)Encephalomyelitis: A general term indicating inflammation of the BRAIN and SPINAL CORD, often used to indicate an infectious process, but also applicable to a variety of autoimmune and toxic-metabolic conditions. There is significant overlap regarding the usage of this term and ENCEPHALITIS in the literature.Paraneoplastic Cerebellar Degeneration: Cerebellar degeneration associated with a remote neoplasm. Clinical manifestations include progressive limb and GAIT ATAXIA; DYSARTHRIA; and NYSTAGMUS, PATHOLOGIC. The histologic type of the associated neoplasm is usually carcinoma or lymphoma. Pathologically the cerebellar cortex and subcortical nuclei demonstrate diffuse degenerative changes. Anti-Purkinje cell antibodies (anti-Yo) are found in the serum of approximately 50% of affected individuals. (Adams et al., Principles of Neurology, 6th ed, p686)Encephalomyelitis, Acute Disseminated: An acute or subacute inflammatory process of the CENTRAL NERVOUS SYSTEM characterized histologically by multiple foci of perivascular demyelination. Symptom onset usually occurs several days after an acute viral infection or immunization, but it may coincide with the onset of infection or rarely no antecedent event can be identified. Clinical manifestations include CONFUSION, somnolence, FEVER, nuchal rigidity, and involuntary movements. The illness may progress to COMA and eventually be fatal. (Adams et al., Principles of Neurology, 6th ed, p921)Limbic Encephalitis: A paraneoplastic syndrome marked by degeneration of neurons in the LIMBIC SYSTEM. Clinical features include HALLUCINATIONS, loss of EPISODIC MEMORY; ANOSMIA; AGEUSIA; TEMPORAL LOBE EPILEPSY; DEMENTIA; and affective disturbance (depression). Circulating anti-neuronal antibodies (e.g., anti-Hu; anti-Yo; anti-Ri; and anti-Ma2) and small cell lung carcinomas or testicular carcinoma are frequently associated with this syndrome.Paraneoplastic Syndromes, Ocular: Ocular manifestations secondary to various NEOPLASMS in which antibodies to antigens of the primary tumor cross-react with ocular antigens. This autoimmune response often leads to visual loss and other ocular dysfunctions.Antigens: Substances that are recognized by the immune system and induce an immune reaction.Myelin-Oligodendrocyte Glycoprotein: A transmembrane protein present in the MYELIN SHEATH of the CENTRAL NERVOUS SYSTEM. It is one of the main autoantigens implicated in the pathogenesis of MULTIPLE SCLEROSIS.Encephalomyelitis, Equine: A group of ALPHAVIRUS INFECTIONS which affect horses and man, transmitted via the bites of mosquitoes. Disorders in this category are endemic to regions of South America and North America. In humans, clinical manifestations vary with the type of infection, and range from a mild influenza-like syndrome to a fulminant encephalitis. (From Joynt, Clinical Neurology, 1996, Ch26, pp8-10)Lambert-Eaton Myasthenic Syndrome: An autoimmune disease characterized by weakness and fatigability of proximal muscles, particularly of the pelvic girdle, lower extremities, trunk, and shoulder girdle. There is relative sparing of extraocular and bulbar muscles. CARCINOMA, SMALL CELL of the lung is a frequently associated condition, although other malignancies and autoimmune diseases may be associated. Muscular weakness results from impaired impulse transmission at the NEUROMUSCULAR JUNCTION. Presynaptic calcium channel dysfunction leads to a reduced amount of acetylcholine being released in response to stimulation of the nerve. (From Adams et al., Principles of Neurology, 6th ed, pp 1471)Myelin Basic Protein: An abundant cytosolic protein that plays a critical role in the structure of multilamellar myelin. Myelin basic protein binds to the cytosolic sides of myelin cell membranes and causes a tight adhesion between opposing cell membranes.Antigens, Neoplasm: Proteins, glycoprotein, or lipoprotein moieties on surfaces of tumor cells that are usually identified by monoclonal antibodies. Many of these are of either embryonic or viral origin.Myelin-Associated Glycoprotein: A myelin protein found in the periaxonal membrane of both the central and peripheral nervous systems myelin sheaths. It binds to cells surface receptors found on AXONS and may regulate cellular interactions between MYELIN and AXONS.Antigens, Bacterial: Substances elaborated by bacteria that have antigenic activity.Stiff-Person Syndrome: A condition characterized by persistent spasms (SPASM) involving multiple muscles, primarily in the lower limbs and trunk. The illness tends to occur in the fourth to sixth decade of life, presenting with intermittent spasms that become continuous. Minor sensory stimuli, such as noise and light touch, precipitate severe spasms. Spasms do not occur during sleep and only rarely involve cranial muscles. Respiration may become impaired in advanced cases. (Adams et al., Principles of Neurology, 6th ed, p1492; Neurology 1998 Jul;51(1):85-93)Myelin Proteins: MYELIN-specific proteins that play a structural or regulatory role in the genesis and maintenance of the lamellar MYELIN SHEATH structure.Myelin Proteolipid Protein: A myelin protein that is the major component of the organic solvent extractable lipoprotein complexes of whole brain. It has been the subject of much study because of its unusual physical properties. It remains soluble in chloroform even after essentially all of its bound lipids have been removed. (From Siegel et al., Basic Neurochemistry, 4th ed, p122)Theilovirus: A species of CARDIOVIRUS which contains three strains: Theiler's murine encephalomyelitis virus, Vilyuisk human encephalomyelitis virus, and Rat encephalomyelitis virus.Multiple Sclerosis: An autoimmune disorder mainly affecting young adults and characterized by destruction of myelin in the central nervous system. Pathologic findings include multiple sharply demarcated areas of demyelination throughout the white matter of the central nervous system. Clinical manifestations include visual loss, extra-ocular movement disorders, paresthesias, loss of sensation, weakness, dysarthria, spasticity, ataxia, and bladder dysfunction. The usual pattern is one of recurrent attacks followed by partial recovery (see MULTIPLE SCLEROSIS, RELAPSING-REMITTING), but acute fulminating and chronic progressive forms (see MULTIPLE SCLEROSIS, CHRONIC PROGRESSIVE) also occur. (Adams et al., Principles of Neurology, 6th ed, p903)Antigens, Surface: Antigens on surfaces of cells, including infectious or foreign cells or viruses. They are usually protein-containing groups on cell membranes or walls and may be isolated.Autoantibodies: Antibodies that react with self-antigens (AUTOANTIGENS) of the organism that produced them.Paraneoplastic Endocrine Syndromes: Syndromes resulting from inappropriate production of HORMONES or hormone-like materials by NEOPLASMS in non-endocrine tissues or not by the usual ENDOCRINE GLANDS. Such hormone outputs are called ectopic hormone (HORMONES, ECTOPIC) secretion.Pemphigus: Group of chronic blistering diseases characterized histologically by ACANTHOLYSIS and blister formation within the EPIDERMIS.Spinal Cord: A cylindrical column of tissue that lies within the vertebral canal. It is composed of WHITE MATTER and GRAY MATTER.Demyelinating Diseases: Diseases characterized by loss or dysfunction of myelin in the central or peripheral nervous system.Antigens, Viral: Substances elaborated by viruses that have antigenic activity.