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ABSTRACT: The Wobbler mouse is a model of human motor neuron disease. Recently we reported the impairment of mitochondrial complex IV in Wobbler mouse CNS, including motor cortex and spinal cord. The present study was designed to test the effect of hyperbaric oxygen therapy (HBOT) on (1) mitochondrial functions in young Wobbler mice, and (2) the onset and progression of the disease with aging. HBOT was carried out at 2 atmospheres absolute (2 ATA) oxygen for 1 h/day for 30 days. Control groups consisted of both untreated Wobbler mice and non-diseased Wobbler mice. The rate of respiration for complex IV in mitochondria isolated from motor cortex was improved by 40% (P<0.05) after HBOT. The onset and progression of the disease in the Wobbler mice was studied using litters of pups from proven heterozygous breeding pairs, which were treated from birth with 2 ATA HBOT for 1 h/day 6 days a week for the animals' lifetime. A "blinded" observer examined the onset and progression of the Wobbler phenotype, including walking capabilities ranging from normal walking to jaw walking (unable to use forepaws), and the paw condition (from normal to curled wrists and forelimb fixed to the chest). These data indicate that the onset of disease in untreated Wobbler mice averaged 36+/-4.3 days in terms of walking and 40+/-5.7 days in terms of paw condition. HBOT significantly delayed (P<0.001 for both paw condition and walking) the onset of disease to 59+/-8.2 days (in terms of walking) and 63+/-7.6 days (in terms of paw condition). Our data suggest that HBOT significantly ameliorates mitochondrial dysfunction in the motor cortex and spinal cord and greatly delays the onset of the disease in an animal model of motor neuron disease.
Neuroscience 02/2003; 120(1):113-20. · 3.38 Impact Factor
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Neurology 01/2002; 57(11):2144-5. · 8.31 Impact Factor
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ABSTRACT: There is an imperative need for the early diagnosis of amyotrophic lateral sclerosis/motor neuron disease (ALS/MND) in the current era of emerging treatments. When evaluating the patient with ALS/MND, the neurologist must consider a number of other motor neuron disorders and related motor syndromes that may have clinical features resembling ALS/MND. The revised Airlie House-El Escorial diagnostic criteria have been established through the consensus of experts meeting at workshops. However, by definition, using these criteria a patient is likely to have fairly advanced disease at the time of a definitive ALS/MND diagnosis. The reasons for the difficulty in making an early ALS/MND diagnosis are several. No surrogate diagnostic marker currently exists for ALS/MND. ALS/MND at its onset is heterogeneous in clinical presentation, its clinical course is variable, and several clinical variants are recognized. In addition, certain motor syndromes, such as monomelic amyotrophy, postpolio muscular atrophy, and multifocal motor neuropathy, can clinically mimic ALS/MND. Therefore, not only may the diagnosis of ALS/MND be clinically missed in the early stages, but worse, the patient may be wrongly labeled as having ALS/MND. The diagnosis of ALS/MND requires a combination of upper motor neuron (UMN) and lower motor neuron (LMN) involvement. Motor syndromes in which the deficit is restricted to the UMN or LMN through the entire course of the disease are described as atypical MND in this review. Approximately 5% of patients with ALS/MND have overt dementia with a characteristic frontal affect. ALS/MND with parkinsonism and dementia is rare outside the western Pacific region. The clinical course of motor disorder in these overlap syndromes does not differ from that in typical ALS/MND.
Seminars in Neurology 07/2001; 21(2):177-87. · 1.64 Impact Factor
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ABSTRACT: We report favorable results of the long term use of mycophenolate in the treatment of three patients with myasthenia gravis (MG), two patients with chronic inflammatory demyelinating polyneuropathy (CIDP), one patient with secondary polymyositis (PM), and one patient with inclusion body myositis (IBM). Side effects were mild. Mycophenolate appears to be a useful addition to the armamentarium of immunosuppressants for treatment of chronic immunologically mediated neuromuscular diseases.
Journal of the Neurological Sciences 05/2001; 185(2):119-22. · 2.35 Impact Factor
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ABSTRACT: The involvement of mitochondrial dysfunction promoting neurodegenerative diseases, including amyotrophic lateral sclerosis (ALS), has been suggested. Histopathological and biochemical mitochondrial abnormalities have been reported in both sporadic and familial patients and suggest the contention that mitochondria may play a key role promoting ALS. Animal models of ALS provide a unique opportunity to study this incurable and fatal human disease. In the present study we tested the hypothesis that alterations in mitochondrial physiology occur in the brain of wobbler mice. No significant difference was found in the respiratory control index or adenosine diphosphate/oxygen ratio values between isolated mitochondria of wobbler and control mice. When pyruvate and malate were used as substrates, oxygen consumption was decreased significantly by approximately 33% in mitochondria isolated from wobbler mouse brain compared to controls. Oxygen consumption in the presence of ascorbate and N,N,N',N'-tetramethyl-p-phenylenediamine (TMPD) was decreased significantly by approximately 21% in wobbler brain mitochondria compared to controls, which suggests impairment in the function of complex IV. These findings are the first demonstration of mitochondrial respiratory chain dysfunction in the brain of the wobbler mouse.
Neuroscience Letters 04/2001; 300(3):141-4. · 2.11 Impact Factor
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Neurology 03/2001; 56(4):571-2. · 8.31 Impact Factor
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ABSTRACT: A 56 year old woman had a 19 month history of a severe subacute progressive cerebellar degeneration, peripheral sensory neuropathy, and urinary incontinence. She was confined to a wheelchair, needed assistance with eating, and her speech was almost unintelligible. No underlying cancer was found despite repeated investigations, and no autoantibodies were demonstrated. She received a 3-month course of intensive immunosuppressant therapy with intravenous immunoglobulin 400 mg/kg per day for 5 days every month, oral cyclophosphamide 50 mg twice or three times a day to maintain the total lymphocyte count between 500 and 750/mm(3), and prednisone 60 mg per day. She experienced dramatic subjective and objective improvement. The dysarthria and the upper extremity dysmetria disappeared, and she regained the ability to write and cook. The lower extremity ataxia improved and she became able to walk with a cane. Urinary incontinence disappeared. A trial of intensive immunosuppressant treatment is worth considering in a patient with a clinical syndrome resembling paraneoplastic disorders, even if an underlying neoplasm and autoantibodies are not demonstrated.
Journal of the Neurological Sciences 10/2000; 178(1):63-5. · 2.35 Impact Factor
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ABSTRACT: Peripheral neuropathy associated with human immunodeficiency virus type 1 (HIV-1) infection is a major cause of morbidity in this patient population. Due to the associated chronic pain, its management has come within the purview of neuropsychiatrists. This paper will focus on the primary pathogenic aspects of HIV-1-associated peripheral neuropathies. The specific syndromes of greatest concern are distal sensory polyneuropathy, toxic neuropathy, inflammatory demyelinating polyradiculoneuropathy, and cytomegalovirus-related progressive polyradiculoneuropathy. The treatments available for these conditions and their efficacy are discussed.
CNS spectrums 06/2000; 5(5):66-72. · 2.20 Impact Factor
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ABSTRACT: Research criteria for the diagnosis of chronic inflammatory demyelinating polyneuropathy (CIDP) were proposed by an Ad Hoc Subcommittee of the American Academy of Neurology (AAN) in 1991, and since then these criteria have been widely used in clinical studies. We have been impressed by the frequent finding of electrophysiological changes of a demyelinating neuropathy in patients whose clinical presentation does not conform to the usually accepted clinical phenotype of CIDP. To determine the clinical spectrum of CIDP, we conducted a retrospective review of patients of the peripheral electrophysiology laboratory of the University of Miami-Jackson Memorial Medical Center. Diagnostic criteria for acquired demyelination of an individual nerve were adapted from the AAN research criteria for the diagnosis of CIDP (1991). Patients were accepted for inclusion when such evidence was demonstrated in at least one motor nerve or at least two sensory nerves. We then reviewed the clinical phenotype and the underlying etiology of the neuropathy in these cases. Eighty-seven patients, 63 male and 24 female, age of onset 4-84 (mean 49.3) years, met these inclusion criteria. Forty-seven patients (54%) had distinct features outside the usual clinical presentation of CIDP. Of these, 15 (17%) had predominantly distal features, 13 (15%) had exclusively sensory polyneuropathy; seven (8%) had markedly asymmetric disease, seven (8%) had associated CNS demyelination, four (5%) had predominant cranial nerve involvement, and one (1%) had only the restless legs syndrome. An associated medical condition that may have been responsible for the acquired demyelinating neuropathy was present in 60% of the patients. We conclude that spectrum of CIDP is broader than would be indicated by the strict application of the AAN research criteria, and that many of the cases meeting more liberal criteria frequently respond to immunosuppressive therapy.
Journal of the Neurological Sciences 03/2000; 173(2):129-39. · 2.35 Impact Factor
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ABSTRACT: To clarify the question of whether Guillain-Barré syndrome (GBS) patients treated with intravenous immune globulin (i.v.IG) relapse at a higher frequency than those treated with plasma exchange (PE), 54 patients with GBS were studied retrospectively. A higher frequency of relapses was noted in the PE-treated patients than in those receiving i.v.IG. The presence of an associated medical condition correlated with an increased risk of relapses, while earlier onset of treatment resulted in a decrease of relapses of GBS. This study found no support for prior suggestions of increased relapses in patients with GBS treated with i.v.IG as opposed to those treated with PE.
Muscle & Nerve 11/1998; 21(10):1327-30. · 2.37 Impact Factor
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ABSTRACT: A morphometric study of the peripheral nervous system at autopsy was undertaken in 11 AIDS patients and 10 controls. The left L4, L5, and S1 dorsal root ganglia (DRG) and samples of the sciatic nerve at the buttock, tibial nerve at the knee, and sural nerve at the ankle were collected. Indices of neuronal/axonal degeneration and of segmental demyelination/ remyelination were measured at each level. The small number of cases and evidence of neuropathy in a number of the control cases resulted in statistical significance for only a limited number of comparisons. Nodules of Nageotte in the DRG were increased fivefold in AIDS cases compared with controls, and axonal degeneration in single-teased nerve fibers was increased 9-fold in the sciatic nerve, 28-fold in the tibial nerve, and 12-fold in the sural nerve. The ratios of AIDS to controls for the density of remaining DRG neurons and large myelinated axons were reduced to 0.71 in the DRG, 0.84 in the sciatic nerve, 0.84 in the tibial nerve, and 0.66 in the sural nerve. Axonal regeneration in single-teased nerve fibers was increased threefold at the sciatic nerve level in AIDS, but was markedly reduced at distal levels. Acute segmental demyelination in single-teased nerve fibers was present to a greater extent than in controls at all levels of the peripheral nerves in the AIDS cases. Remyelinating fibers were increased compared with controls only in the proximal sciatic nerve. No case showed the changes of cytomegalovirus infection. In a parallel immunohistochemical study of these AIDS peripheral nerves, T-cell and macrophage infiltration, with cytokine expression, was demonstrated. The pathological process in the neuropathy of terminal AIDS appears to be a multifocal immunologically mediated inflammatory disease, with increased density of macrophages and T cells at all levels of the peripheral nervous system, producing segmental demyelination and axonal degeneration. Reparative processes (axonal regeneration and remyelination) occurred only at the most proximal levels of the nerves.
Muscle & Nerve 10/1998; 21(9):1188-95. · 2.37 Impact Factor
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ABSTRACT: We describe a patient with a 3 year history of progressive polyneuropathy that rendered him severely quadriparetic and bedridden. Work up revealed an IgG lambda monoclonal spike and multifocal osteosclerotic myeloma. Remarkable improvement followed combined treatment with surgical excision, radiation therapy, and chemotherapy using chlorambucil, danazol, and hydrocortisone. Hence, we believe that aggressive local therapy associated with systemic chemotherapy should be considered in severely affected patients with multifocal osteosclerotic myeloma and peripheral neuropathy.
Muscle & Nerve 09/1997; 20(8):1035-7. · 2.37 Impact Factor
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ABSTRACT: Painful distal sensory polyneuropathy (DSP) is the most common peripheral neuropathy in patients with human immunodeficiency virus-1 (HIV-1) infection. There is no specific therapy for DSP, and nonspecific treatment with pain blockers and narcotic agents generally fails to adequately control the symptoms. We report two patients who had subacute painful neuropathy in the B2 (formerly AIDS-related complex [ARC]) stage of HIV-1 infection. Neurophysiologic studies revealed predominantly axonal sensorimotor neuropathy. Sural nerve biopsy in both cases showed a necrotizing vasculitis. Treatment with corticosteroids resulted in rapid relief of pain, followed by arrest of the neuropathic process. Although not previously emphasized, vasculitic neuropathy must be considered among the treatable causes of painful sensory neuropathy in HIV-1-infected individuals.
Neurology 01/1997; 47(6):1446-51. · 8.31 Impact Factor
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ABSTRACT: Various degrees of neuronal degeneration have been found in lumbosacral dorsal root ganglia of patients with acquired immunodeficiency syndrome (AIDS). To characterize the subpopulations of primary sensory neurons affected in AIDS, we immunostained dorsal root ganglion tissues from 11 AIDS patients and six controls using antibodies to the calcium binding proteins, parvalbumin and calbindin D-28 k. In controls, the proportion of neurons containing parvalbumin and calbindin was 18.0% and 22.4%, respectively. The majority of parvalbumin-positive neurons, which are thought to be proprioceptive neurons, were of medium to large size, while calbindin was found in both large- and small-sized neurons. The density of parvalbumin-immunoreactive neurons was reduced by 7.3% in AIDS patients, but the density of calbindin-immunoreactive neurons was preserved. Furthermore, in AIDS cases, the number of parvalbumin-positive neurons was reduced more in dorsal root ganglia in which human immunodeficiency virus (HIV) antigen was detected than in HIV-negative ganglia. These results suggest that specific subpopulations of sensory neurons positive for parvalbumin may be differentially affected over the course of AIDS, and that this could be related to peripheral neuropathy which frequently occurs in the late stages of AIDS.
Neuropathology and Applied Neurobiology 09/1996; 22(4):293-301. · 3.80 Impact Factor
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ABSTRACT: We describe a two-generation family with combined clinical features of myoclonic epilepsy, progressive external ophthalmoplegia (PEO), proximal myopathy, pigmentary retinopathy, progressive deafness, basal ganglia calcification, and ragged-red fibers in a muscle biopsy specimen. One family member died unexpectedly at age 22 years. The molecular tests revealed an A-to-G transition at nucleotide position 3243 of the mitochondrial tRNA(Leu(UUR)) gene. No one in this family had stroke-like episodes. Although the propositus (a 28-year-old woman) had a significant number of white hairs, the percentage of mutant mtDNA in white-hair roots was not different from that in the colored-hair roots. Our findings suggest that the 3243 mutation can be associated with mixed clinical features of myoclonic epilepsy with ragged-red fibers (MERRF) and PEO and that a preferential increase in the levels of the mutant mtDNA is not related to graying of hair, and hence to the hypothesized production of premature aging of cells.
Neurology 06/1996; 46(5):1334-6. · 8.31 Impact Factor
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ABSTRACT: We studied lumbosacral dorsal root ganglia (DRGs) from 10 patients with acquired immunodeficiency syndrome (AIDS) and five controls using immunocytochemistry, in situ hybridization and NADPH-diaphorase (NADPHd) histochemistry. Human immunodeficiency virus (HIV)-1 RNA was detected in five AIDS cases, and HIV-1 p24 antigen was found in four of these patients. The densities of nodules of Nageotte (nN), macrophages and major histocompatibility complex-class II-positive cells were significantly increased in the DRGs of AIDS patients compared to controls. Cytomegalovirus antigen was observed in the DRGs of four AIDS cases and one control, but without its presence being related to neuronal degeneration. Furthermore, we detected tumor necrosis factor, interferon-gamma, interleukin (IL)-1 beta, and IL-6 in the DRGs from AIDS patients. Using NADPHd histochemistry, we showed that the number of NADPHd-positive neurons was significantly increased in the DRGs of AIDS patients compared to controls, implying upregulation of nitric-oxide (NO) production in AIDS DRGs. Generally, there were increased numbers of nN in DRGs which contained more NADPHd-positive neurons. Additionally, immunoreactivity for an inducible form of NO synthase was detected in interstitial cells in AIDS DRGs. These results suggest that reactive inflammation, including the production of cytokines, occurs in the DRGs of AIDS patients and that excessive production of NO may be related to neuronal degeneration in AIDS DRGs.
Journal of the Neurological Sciences 04/1996; 136(1-2):117-28. · 2.35 Impact Factor
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ABSTRACT: The mutation in X-linked bulbospinal muscular atrophy (XBSMA) is an increased CAG triplet repeat coding for a polyglutamine domain in the gene for the androgen receptor. This might impair the effect of testosterone on motor neurons, leading to their progressive degeneration. We report a trial of high-dose oral testosterone therapy in two brothers with XBSMA. Patient 1 received 37.5 mg of testosterone daily for more than 18 months, and Patient 2 received 25 mg per day for six months, both in combination with exercise therapy. Patient 1 showed improvement of up to 300% in muscle work output. Patient 2, who did less exercise, had no symptomatic improvement. These results indicate that exogenous testosterone therapy is not harmful, and may produce functional improvement when combined with exercise. We hypothesize that high-dose testosterone may reduce a toxic gain of function that the mutation produces, perhaps by inhibiting glutamate neurotoxicity.
Journal of the Neurological Sciences 03/1996; 135(2):158-61. · 2.35 Impact Factor
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ABSTRACT: Central nervous system (CNS) involvement is common during human immunodeficiency virus type-1 (HIV-1) infection. The neurologic disease of the CNS most frequently observed during acquired immunodeficiency syndrome (AIDS) is HIV-1-associated cognitive/motor complex or AIDS dementia complex (ADC), which is most likely a direct consequence of HIV-1 infection of the CNS. The peripheral nervous system (PNS) is also affected in HIV-1-infected individuals and there are several features of immune- and cytokine-related pathogenesis in both the CNS and PNS that are reviewed. Several lines of evidence demonstrate aspects of immune activation in the CNS and peripheral nervous system (PNS) of HIV-1-infected individuals. The relative paucity of HIV-1 expression in contrast to widespread functional and pathologic changes in the CNS and PNS of AIDS patients, and the lack of evidence of productive infection of HIV-1 in neuronal cells in vivo lead to the possibility of indirect or immunopathogenic mechanisms for HIV-1-related neurologic diseases. Proposed mechanisms of neuronal and glial cell damage are injury of oligodendrocytes by tumor necrosis factor-alpha (TNF-alpha) released from activated macrophage/microglia, calcium-dependent excitoneurotoxicity induced by gp120 HIV-1 envelope protein, N-methyl-D-aspartate (NMDA) receptor-mediated neurotoxicity by quinolinic acid (a product of activated macrophages), cell injury by HIV-1-specific cytotoxic T cells, and apoptosis of oligodendrocytes or neurons triggered by interaction between cell surface receptors and HIV-1 gp120 protein. Common to those mechanisms is the dependence on cellular activation with expression of proinflammatory cytokines (TNF-alpha, interleukin-1). Amplification of activation signals through the cytokine network by macrophage/astrocyte/endothelial cell interactions, and cell-to-cell contact between activated macrophages and neural cells by upregulation of adhesion molecules dramatically enhances the toxic effect of macrophage products. Expression of immunosuppressive cytokines such as interleukin-4, interleukin-6, and transforming growth factor-beta is also increased in the CNS and PNS of HIV-1-infected patients. This may serve as neuroprotective and regenerative mechanism against insults to nervous system tissue.
Advances in Neuroimmunology 02/1995; 5(3):335-58.
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ABSTRACT: We examined the immunopathology and the expression of human immunodeficiency virus type 1 (HIV-1) in lumbosacral dorsal root ganglia (DRGs) from 16 patients with acquired immunodeficiency syndrome (AIDS) and 10 HIV-1-seronegative controls. Using in situ hybridization, we detected HIV-1 RNA in a few perivascular cells in DRGs from five of 16 AIDS patients (31%). In addition, using polymerase chain reaction, we detected HIV-1 DNA more frequently in DRGs from four of five AIDS patients (80%) examined. We detected interleukin-6 (IL-6) immunoreactivity in endothelial cells in DRGs from seven of 16 AIDS patients (44%) but from none of 10 HIV-1-seronegative controls (0%). We found more nodules of Nageotte, CD8+ T lymphocytes, and intercellular adhesion molecule-1 (ICAM-1)-positive endothelial cells and mononuclear cells in DRGs from AIDS patients than in DRGs from controls. Increased numbers of nodules of Nageotte in DRGs of AIDS patients were associated with detection of HIV-1 RNA by in situ hybridization and detection of IL-6 by immunohistochemistry. We conclude that low levels of replication of HIV-1, through cytotoxic T lymphocytes or expression of cytokines, may play a role in the subclinical degeneration of sensory neurons frequently observed in DRGs of AIDS patients.
Neurology 07/1994; 44(6):1120-30. · 8.31 Impact Factor
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ABSTRACT: Previous reports of primary lumbosacral plexopathy (LSP) have stressed the benign nature of the syndrome. No effective treatment is known for the occasional patients who do not recover or who have relapses. We report two patients presenting with a progressive form of idiopathic LSP. Both patients showed remarkable improvement on high-dose intravenous immunoglobulin therapy. We suggest that these patients represent a treatable subgroup of LSP.
Neurology 03/1994; 44(2):248-50. · 8.31 Impact Factor
