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PubMed1982

Features of central and peripheral nerve conduction in demyelinating diseases and specific neuropathies in Japan.

Short latency SEPs, either with median nerve stimulation at the wrist or with tibial nerve stimulation at the ankle, were recorded in 14 patients with localized subcortical lesions, 27 Japanese patients with multiple sclerosis (MS), 5 patients each of "polyneuropathy with pigmentation, oedema, hypertrichosis and plasma cell dyscrasia (polyneuropathy with PEHP)" and subacute myelo-optico-neuropathy (SMON), and healthy adults for controls. The component N13 with median nerve stimulation was localized at C4 to C7 electrodes, and was absent in cases with cervical cord lesions but present in cases with lesions anywhere in the medulla or above. N13 was concluded to be generated in the cervical cord. Short latency SEP was found applicable to clinical investigation of the peripheral and central conduction. It was found useful for detecting subclinical demyelinating lesion in MS, and this was especially so with tibial nerve stimulation. In "polyneuropathy with PEHP," the present physiological findings (prolonged interpeak latency from N9 to N13, and amplitude reduction and delayed peak latency of N9 with median nerve stimulation) were in conformity with neuropathological findings consisting of an extensive segmental demyelination in the spinal root, and axonal degeneration and segmental demyelination in the peripheral nerve. In SMON, the primary involvement of the central conduction, exclusively in the distal portion of the gracile fasciculus, was substantiated by the present physiological findings (prolonged interpeak latency from N20 to P40 with tibial nerve stimulation, but normal SEP with median nerve stimulation).

Brain↗
PubMed1995

[Demyelinating polyradiculitis in neuro borreliosis].

Demyelinating neuropathy is considered a rare complication of Lyme borreliosis. We report a case of meningoradiculitis due to Borrelia burgdorferi in which the neurophysiological analysis showed evidence of restricted demyelinating involvement of the nerve roots and plexus, with no peripheral involvement or signs of distal axonal lesions. Lyme disease, therefore, can in fact be associated with demyelinating polyradiculitis with no peripheral nerve damage.

Aged↗
PubMed1994

A case of demyelinating disease with clinical and radiological features mimicking cerebral tumor.

Demyelinating disease may present with clinical and radiological features mimicking brain tumor. A 43-year-old man was admitted because of progressive right hemiparesis, facial weakness and dysarthria. Computed tomographic scans revealed two expansive lesions in the left frontal lobe and midbrain, respectively. A brain tumor or metastatic lesion was suspected. The patient underwent left frontal craniotomy and the surgical biopsy revealed a demyelinating process. The patient, however, had a poor response to steroid treatment and died two months later. The possible nature of demyelinating disease in this case is discussed.

Adult↗
PubMed1994

Pathology of inflammatory demyelinating neuropathies.

GBS and CIDP are multifocal demyelinating diseases with lesions widely disseminated throughout the peripheral nervous system including cranial nerves, terminal intramuscular nerves and autonomic nerves. In both conditions myelin destruction is mediated by macrophages that attack myelin without disturbing the integrity of Schwann cells. The same pattern of myelin breakdown occurs in EAN, providing additional evidence that these disorders are immune-mediated. Recent autopsy and biopsy studies have challenged the view that lymphocytes are always present in newly forming lesions, an observation supporting a role for humoral immunity in the pathogenesis of some cases of GBS and CIDP. In both conditions neurological dysfunction is related to both myelin destruction and axonal loss. In some cases of CIDP there is the additional factor of impaired remyelination. Other chronic demyelinating neuropathies that may be immune-mediated differ from CIDP in presenting as solitary or multiple mononeuropathies. These can be classified into cases with and without evidence of widespread demyelination, cases with and without focal nerve enlargements, and a pure motor variant, multiple motor neuropathy associated with elevated anti-GM1 ganglioside antibody titres.

Arthus Reaction↗
PubMed1994

[A pathogenic study of chronic inflammatory demyelinating polyradiculoneuropathy in a patient with hepatitis B infection].

We immunologically examined the pathogenesis of chronic inflammatory demyelinating polyradiculoneuropathy in a patient with HB hepatitis. A 41-year-old male clerk has been suffered from muscle weakness, tingling and numbness in the distal portion of all limbs. All symptoms were compatible with the typical patterns of chronic inflammatory demyelinating polyradiculoneuropathy. We examined the patient's serum and biopsied sural nerve, using histochemical and immunological techniques. We detected the band that reacted with anti-HBs antibody in the sural nerve in western blotting. The result indicated that HBs antigen was expressed on the peripheral nerves in the patient. There were no anti-peripheral nerve antibodies neither in the sural nerve or serum. There was no increase of immune complex in the serum. No deposition of immunoglobulins and complements were detected in the sural nerve. Immunoadsorption therapy had no effect on this patient, but administration of prednisolone improved his symptoms drastically. These findings suggest that a cytotoxic T cell may had played a more important role than humoral factors in this patient's nerve injury. Though the pathogenesis of chronic inflammatory demyelinating polyradiculoneuropathy remains unclear, our findings seem to be very interesting in that they go some way toward clarifying the pathogenesis of this disease.

Adult↗
PubMed1993

Macrophages and endothelial cells express intercellular adhesion molecule-1 in immune-mediated demyelination but not in Wallerian degeneration of the rat peripheral nervous system.

BACKGROUND: Intercellular adhesion molecule-1 (ICAM-1) plays an important role in immune responses, especially in T cell/endothelial cell and T cell/macrophage interactions. This study reports the cellular localization of ICAM-1 during immune-mediated demyelination of the peripheral nervous system induced by adoptive transfer of P2 specific T cells. EXPERIMENTAL DESIGN: Cryosections 1 micron thick of ventral roots of rats with experimental autoimmune neuritis were labeled with a monoclonal antibody against rat ICAM-1. RESULTS: Numerous ICAM-1 positive cells were present before and shortly after the onset of clinical disease from days 4 to 6 after cell transfer. By day 8, their number had greatly decreased. ICAM-1 positive infiltrating cells could be identified as ED1 positive macrophages. Moreover, endothelial cells expressed ICAM-1. Schwann cells and T cells were ICAM-1 negative. While at early stages of experimental autoimmune neuritis, ICAM-1 and Ia colocalized on macrophages but not endothelial cells, Ia persisted for a longer period in nerve roots than ICAM-1. After nerve transection, macrophages entering the distal stump and endothelial cells did not express ICAM-1. CONCLUSIONS: The presence of ICAM-1 immunoreactivity in peripheral nerve indicates an underlying immune-mediated process. Among other cytokines interferon-gamma, which is transiently expressed in nerves during immune-mediated demyelination but not after nerve transection, could be one mediator that induces ICAM-1 in immune-mediated demyelination of the peripheral nervous system.

Animals↗
PubMed1993

[Chronic inflammatory demyelinating polyneuropathy in childhood].

Clinical, electrophysiological and histopathological findings in 6 children with steroid-responsive acquired demyelinating neuropathy are presented. The clinical features and nerve conduction findings are basically similar to those of chronic inflammatory demyelinating neuropathy (CIDP) in adults, although early-onset cases had prominent pes cavus deformity and thickened nerves, which are rare findings in acquired neuropathies in adults. The diagnostic criteria of adult CIDP can be adopted for most of the cases, however, repeated electrophysiological tests may be required to identify multifocality of the nerve lesion, especially when conduction block is not apparent before treatment. The biopsied sural nerves showed many thinly-myelinated fibers, subperineurial and endoneurial edema, and cellular infiltrations. Varied fascicular involvements were common. Two cases with almost complete or considerable loss of myelinated fibers in the biopsied sural nerve revealed good clinical response to steroid therapy. The degree of nerve degeneration in the sural nerve thus, may not be helpful to estimate the prognosis and the responsiveness to treatment. Therapeutic trials should be employed when the main conduction findings are those of demyelinating neuropathies, even if genetically-determined neuropathy is suggested from the clinical pictures.

Adolescent↗
PubMedDate not supplied

Induction of Theiler's murine encephalomyelitis virus (TMEV)-induced demyelinating disease in genetically resistant mice.

Theiler's murine encephalomyelitis virus-induced demyelinating disease, a murine model for multiple sclerosis, is the result of persistent infection which leads to a T cell-mediated immunopathology. Susceptible strains develop virus-specific DTH responses while resistant strains do not, and this response has been proposed as the basis for inflammation and demyelination. (C57BL/6 x DBA/2)F1 hybrid animals, normally resistant to TMEV-induced demyelinating disease, become susceptible when treated in vivo prior to infection with low dose cyclophosphamide. Comparable pretreatment of other resistant animals, C57BL/6 and CB6 (BALB/c x C57BL/6) F1 hybrids, does not render them susceptible (despite the H-2 identity of CB6F1 and B6D2F1 hybrids). Thus the "latent" susceptibility in B6D2F1 hybrids must be attributed to non-H-2 genes from the susceptible D2 parent. Resistance can be restored to CY-treated B6D2F1 animals by the adoptive transfer of splenic cells (including T cell enriched populations) from non-CY-treated donors. Resistance to TMEV-IDD in these animals, therefore, may involve active inhibition of a "latent" disease susceptibility.

Animals↗
PubMedDate not supplied

[Chronic demyelinating polyneuropathy associated with multiple sclerosis: a patient with two diseases].

We studied the clinical, paraclinical and laboratory findings of a patient suffering from multiple sclerosis (MS) with chronic demyelinating polyneuropathy. As well as being a new case of demyelination of the central and peripheral nervous system not normally associated with the presence of antiganglionic antibodies, our patient presented clinical signs distinct from each disease with the characteristic abnormalities of cerebrospinal fluid (CSF) (cytological albumin dissociation at the moment when an outbreak appeared at the peripheral level and an increase in intrathecal secretion when the outbreak was at the central nervous system level). Demyelinating diseases of the central and peripheral nervous systems are a field of great interest in trying to find the antigenic bull's eye for MS.

Adult↗
PubMed1995

Spontaneous CNS remyelination in beta 2 microglobulin-deficient mice following virus-induced demyelination.

Animal models with selective genetic immunodeficiencies are useful tools to identify pathogenic mechanisms of disease. Resistant (C57BL/6F 129/J) (H-2b) mice are rendered susceptible to Theiler's murine encephalomyelitis virus-induced demyelination by genetic disruption of the beta 2 microglobulin gene [beta 2 m(-l-)]. The absence of beta 2 m prevents the expression of major histocompatibility complex class I molecules and normal levels of functional CD8+ T cells. We tested whether genetic depletion of beta 2 m would permit CNS remyelination after chronic demyelination induced by the Daniel's strain of Theiler's virus. In contrast to the minimal spontaneous remyelination observed in SJL/J mice after infection with the Daniel's strain of Theiler's virus, chronically infected beta 2 m(-I-) mice showed extensive and progressive spontaneous CNS remyelination at 6, 12, and 18 months after infection. Spontaneous remyelination by both oligodendrocytes and Schwann cells occurred despite the presence of persistent virus antigen and RNA, but was associated with diminished virus-specific humoral and delayed-type hypersensitivity responses. These experiments support the hypothesis that the immune response inhibits myelin regeneration after virus-induced CNS demyelination.

Animals↗
PubMed1996

Flow cytometric and functional analyses of central nervous system-infiltrating cells in SJL/J mice with Theiler's virus-induced demyelinating disease. Evidence for a CD4+ T cell-mediated pathology.

Theiler's murine encephalomyelitis viruses (TMEVs) are endemic enteric pathogens of mice that cause immune-mediated, chronic, progressive, central nervous system (CNS) demyelinating disease in susceptible strains. Analysis of T cell phenotype and functional state from TMEV-infected SJL/J mice by flow cytometry reveals that 13.5 to 25% of the CD4+ T cells in the CNS express high affinity IL-2R, a marker of recent T cell activation, whereas splenic levels of CD4+IL-2R+ T cells generally range between 2 and 8.5%. In contrast, very few CD8+ T cells (<1-2%) from either site express IL-2R. From days 20 to 119 postinfection, the percentage of CD4+IL-2R+ T cells increases gradually in the CNS, but varies little in the spleen. CD4+ T cells isolated from the spinal cord of infected mice proliferate in vitro in response to viral Ag. Similar T cell phenotypes were found in experimental autoimmune encephalomyelitis, an established model of CD4+ T cell-mediated demyelination. In addition, most CD4+ and CD8+ T cells in CNS isolates from TMEV-infected mice are CD44+, indicating that prior activation may be required to traffic through and/or be retained in the CNS. Finally, TCR V beta region usage as well as IL-2R expression by individual V beta region subsets are heterogeneous in both the CNS and spleen. These results are consistent with a model in which a polyclonal population of TMEV-specific, CD4+ Th1 cells plays a major effector role in the demyelinating process.

Animals↗
PubMed1977

Lead neuropathy: 2. Random distribution of segmental demyelination among "old internodes" of myelinated fibers.

One-hundred teased fibers of proximal and of distal sural nerve of five rats fed lead carbonate for 3 months were evaluated to see whether the pattern of segmental demyelination was random or clustered. If the evaluation was done by the length of the "territory of an old internode" (the region of one Schwann cell) a significant departure from randomness could not be shown for the majority of nerves. However, if the evaluation was by regions with and without myelin a highly clustered pattern of segmental demyelination was found. Since several remyelinated internodes form following internodal segmental demyelination, of one "old internode" the latter method of analysis would be expected to show clustering even though Schwann cell damage was random. Therefore the second method of analysis cannot be used to assess randomness of Schwann cell involvement in neuropathy. We interpret these studies as supporting the concept that Schwann cells are primarily and ubiquitously involved in lead neuropathy of the rat. Possible mechanisms of such primary Schwann cell injury are direct damage from lead of the intrafascicular interstitial fluid or from increased intrafascicular interstitial pressure.

Animals↗
PubMedDate not supplied

Measure of magnetization transfer in multiple sclerosis demyelinating plaques, white matter ischemic lesions, and edema.

PURPOSE: To define the percentage of magnetization transfer of multiple sclerosis (MS) plaques, ischemic white matter lesions, and vasogenic edema to determine whether this measurement can help differentiate these entities. METHODS: Findings were compared in 25 patients with proved MS, 20 patients with white matter ischemic lesions, and 72 patients with white matter edema (caused by tumors, infections, or acute/subacute infarctions) in the periventricular system, centrum semiovale, and subcortical white matter. Magnetization transfer was performed using an on-resonance binomial pulse. The percentage of magnetization transfer of the normal white matter was also calculated. RESULTS: Magnetization transfer was significantly higher in white matter ischemic lesions (range, 31% to 38%; mean, 34% +/- 0.6%) than in demyelinating plaques of MS (range, 19% to 28%; mean, 22.5% +/- 1%) and in edema (range, 29% to 37%; mean, 30.2% +/- 0.4%). No statistical difference in percentage of magnetization transfer was found among lesions in the periventricular system (34% +/- 0.6%), centrum semiovale (35% +/- 0.5%), or subcortical white matter (33% +/- 0.6%), or in vasogenic edema associated with tumors, infections, or infarction. CONCLUSION: Differences in magnetization transfer suggest less change of demyelination in white matter ischemic lesions than in MS plaques and are significantly different in this respect from similar MS plaques. Magnetization transfer of edema was less than that of normal white matter or fell between ischemic abnormalities and MS plaques. Percentages of magnetization transfer below the mid-20% range is highly suggestive of demyelination. Vasogenic edema, our surrogate for increased water content of white matter, caused a decrease in the percentage of magnetization transfer.

Adult↗
PubMed1996

[A case of acute disseminated encephalomyelitis (ADEM) associated with demyelinating peripheral neuropathy].

A 41-year-old man had common cold on April 10, 1991. Five days after this illness he developed fever, dysarthria, visual field impairment, gait disturbance and consciousness disturbance followed. On admission in another hospital, cerebrospinal fluid showed 341/mm3 cells (303 mononuclear cells, 33 polynuclear cells, 5 red cells), protein of 238 mg/dl, and sugar of 59 mg/dl. One month later, the neurological examinations revealed flaccid paraparesis, decreased deep tendon reflexes in the lower extremities, bilateral positive Babinski and Chaddock reflexes, positive Beevor sign, stocking type superficial sensory disturbance, diminished vibration sense in the lower extremities and neurogenic bladder. Eight months later, he improved to be able to walk by himself, but decreased Achilles tendon reflexes, bilateral positive Babinski and Chaddock reflexes and paresthesia over both feet were noted neurologically. Nerve conduction study revealed reduced conduction velocities at tibialis anterior nerves, sural nerves and no response on both deep peroneal nerves. A 1 micron thick epon section of a biopsied sural nerve with toluidine blue stain showed a decreased number of myelinated fibers (6394/mm2) with many thinly myelinated fibers and Renaut bodies. There was no edema nor cell infiltration. Electronmicroscopical findings of their ultrathin sections showed many collagen pockets, denervated Schwann cell clustering and a few onion bulb formations. Teased fiber preparations suggested segmental demyelination and remyelination in many fibers. This case could be regarded as a case of ADEM associated with demyelinating peripheral neuropathy, and the possibility of the simultaneous demyelinating process in the central and peripheral nervous system was discussed.

Adult↗
PubMed1997

Demyelination induced by protein kinase C-activating tumor promoters in aggregating brain cell cultures.

The plasticity of mature oligodendrocytes was studied in aggregating brain cell cultures at the period of maximal expression of myelin marker proteins. The protein kinase C (PKC)-activating tumor promoters mezerein and phorbol 12-myristate 13-acetate (PMA), but not the inactive phorbol ester analog 4alpha-PMA, caused a pronounced decrease of myelin basic protein (MBP) content and 2',3'-cyclic nucleotide 3'-phosphohydrolase (CNP) activity. In contrast, myelin/oligodendrocyte protein (MOG) content was affected relatively little. Northern blot analyses showed a rapid reduction of MBP and PLP gene expression induced by mezerein, and both morphological and biochemical findings indicate a drastic loss of compact myelin. During the acute phase of demyelination, only a relatively small increase in cell death was perceptible by in situ end labeling and in situ nick translation. Basic fibroblast growth factor (bFGF) also reduced the levels of the oligodendroglial differentiation markers and enhanced the demyelinating effects of the tumor promoters. The present results suggest that PKC activation resulted in severe demyelination and partial loss of the oligodendrocyte-differentiated phenotype.

Animals↗
PubMed1997

[Recent advances of immune therapies for demyelinating neuropathies].

Most of acquired demyelinating neuropathies are caused by immune-mediated processes. Therefore, we can treat these neuropathies to control underlying immune abnormality. We review the recent therapies and show possible strategies in the future. (1) Recent therapies Guillain-Barré syndrome should be treated quickly and intensively in the first week of the disease with plasmapheresis (PP). Intravenous immunoglobulin (IVIG) is as effective as PP. IVIG is under phase 3 clinical trial in Japan. Chronic inflammatory demyelinating polyneuropathy (CIDP) is treated with corticosteroids, PP or IVIG. Corticosteroids or PP is the first choice. For severe or resistant cases, combined therapy or immunosuppressants, such as cyclophosphamide pulse therapy, should be considered. Polyneuropathy with IgM-MGUS (monoclonal gammopathies of undetermined significance) is treated with PP, immunosuppressants or these combinations to decrease serum IgM, especially for cases with anti-MAG antibody, because the autoantibody induces demyelination by itself. (2) Future strategies Immunopathogenesis may differ among cases with Guillain-Barré syndrome or CIDP. The best therapy will be chosen individually, according to appropriate immunologic tests. In CIDP, immunomodulation therapies, that are similar ones in multiple sclerosis, will be considered to maintain improvement.

Demyelinating Diseases↗
PubMed1976

The initial structural lesion in serum-induced demyelination in vitro.

Myelinated cultures of mouse spinal cord were exposed to sera obtained from rabbits affected by experimental allergic encephalomyelitis following challenge with whole white matter in complete Freund's adjuvant. In the presence of complement, the tissue response begins with an increased birefringence of its myelin sheaths. This is rapidly followed by a gamut of changes leading to demyelination. This study reports that, in the absence of complement, the response is arrested at the stage of increased birefringence. In this way, this early stage of the demyelinating process was available for detailed examination by light and electron microscopy. The brightened myelin sheaths appeared with a few hours of exposure and were seen around all axons and sometimes around cell bodies. This was often accompanied by abrupt breaks in the sheaths and angularly shaped myelin figures. Examination by electron microscope revealed a uniform increase in the myelin period from 11 nm. to 22 nm. The normally double intraperiod line was increased to four electron-dense leaflets, the additional two appearing to be derived from the close apposition of an additional electron-dense layer on the outer surface of the myelin sheath or oligodendrocytic membrane. Oligondendrocytes responsed with a prolific growth of processes whose membranes compacted to form swollen myelin. Neurons, astrocytes, and neuropil showed no changes. In its early stages, at least, the swelling was reversible. It would appear, therefore, that we have isolated the first stage of antiserum-induced demyelination in vitro, a stage which is now available for further study.

Animals↗
PubMed1998

B-cell-deficient mice develop experimental allergic encephalomyelitis with demyelination after myelin oligodendrocyte glycoprotein sensitization.

Myelin oligodendrocyte glycoprotein (MOG) induced experimental allergic encephalomyelitis (EAE) is an animal model for the central nervous system disease multiple sclerosis (MS). The roles of individual components of the immune system have not been completely defined in the mouse model, and to determine the role of B cells and Abs in the induction of EAE and demyelination, B cell-deficient muMT (H-2b) mice were immunized with MOG peptide 35-55. The muMT mice were susceptible to MOG-induced EAE and developed a chronic sustained disease, with inflammatory lesions and primary demyelination in the spinal cord, brain, and optic nerves, similar to that seen in wild-type C57BL/6 mice. The inflammatory cells in the central nervous system of muMT mice included both activated and memory T cells and macrophages. The data suggest that B cells and Abs are not necessary for primary demyelination in MOG-induced EAE in mice.

Amino Acid Sequence↗