Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0851184 (thinning)
 11,252 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A study of the sequential morphological changes in the peripheral nerve induced by experimental inhalation exposure of methyl n-butyl ketone (MBK) revealed that the earliest change was an increase in the number of neurofilaments in the large myelinated nerve fibers. This change occurred prior to axonal swelling or myelin thinning. As the duration of exposure lengthened the number of neurofilaments gradually increased and ultimately produced axonal swelling with secondary thinning of the myelin sheath. This appears to be the pathogenesis of the "giant axonal" neuropathy. Another change observed early in this neuropathy was the presence of inpouchings of the myelin sheath, which also increased in number in parallel to the duration of exposure. A careful study of the sequential changes in the entire motor unit did not show a predilection for early morphological changes at the axon terminal. Abnormalities at the neuromuscular junction occurred only after a full spectrum of changes were seen in the main nerve trunk, nerve roots and intramuscular nerves. An important observation was the marked potentiation of peripheral neurotoxicity observed when animals were exposed to MBK in combination with methyl ethyl ketone (MEK) at a ratio of 1:5, MBK:MEK. The latter solvent showed no neurotoxic effect alone. This might help explain a recent outbreak of a polyneuropathy affecting many workers. One further observation was that the sural nerve of a patient with prolonged exposure to MBK showed changes similar to those induced experimentally.
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PMID:Peripheral nerve changes induced by methyl n-butyl ketone and potentiation by methyl ethyl ketone. 17 32

Seven men aged 17 to 22 years developed severe distal symmetrical predominately motor polyneuropathy after repeated inhalation of a commercially available brand of lacquer thinner. Motor nerve conduction velocities were markedly slowed. Fascicular biopsy specimens of sural nerve showed a striking loss of myelinated nerve fibers. Prominent neurofilamentous masses resulted insegmental paranodal distention of axons with secondary thinning and retraction of myelin from the node of Ranvier. Autopsy material from one case revealed central chromatolysis of anterior horn cells in the lumbosacral enlargement and axonal swellings in the fasciculus gracilis. One or more volatile hydrocarbons contained in the lacquer thinner involved may be neurotoxic if inhaled to excess any many cause a neuropathy with characteristic pathological features.
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PMID:Pathology of lacquer thinner induced neuropathy. 18 61

Although industrial exposure to n-hexane is known to cause neuropathy, it is less well recognized that inhalation of n-hexane present in the vapors of some commercial contact cements is also neurotoxic to peripheral nerves. A young man with a long history of addictive glue-sniffing developed severe distal symmetrical polyneuropathy several months after switching to a cement containing n-hexane and gradually improved several months after switching to another cement containing no n-hexane. Fascicular biopsy of radial cutaneous nerve showed striking segmental distention of axons by neurofilamentous masses with secondary thinning of myelin sheath, paranodal myelin retraction, and widening velocities were correspondingly slow. We conclude that n-hexane used as a solvent in some contact cements may be neurotoxic when inhaled to excess and, further, that the neuropathy has characteristic electrophysiological and pathological features.
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PMID:Glue-sniffing neuropathy. 111 59

Adrenomyeloneuropathy (AMN), a clinical variant of child adrenoleukodystrophy (ALD), is an adult-onset progressive disorder which presents spastic paraparesis with peripheral nerve involvement and affects mainly the pyramidal tracts from the brainstem to the spinal cord. We report a case of AMN in which serial MRI showed unusual development of areas of high signal in the right striatum. The patient was in good health until the age of 12, when he began to lose his hair. At age 25 he started to have progressive gait disturbance and erectile impotence. In his first admission to our hospital at age 33, he showed diffuse baldness. He was intelligent but childish. His cranial nerves were normal. Muscle strength was weak (3-4/5) in the lower extremities. Deep tendon reflexes were hyperactive in the lower extremities while normal in the upper extremities. Babinski signs were elicited bilaterally. Pinprick and vibratory sensation was impaired in the lower legs. Proprioceptive sensations were normal. Co-ordination was intact. There were urinary incontinence and impairment of erection with preserved libido and ejaculation. Routine laboratory data including hematological studies, serum chemistry and urinalysis were all normal except for mild hyperlipidemia. Serum cortisol response to ACTH was low and serum levels of very long chain fatty acids were increased. Nerve conduction studies were abnormal and consistent with peripheral polyneuropathy. A biopsy specimen of left sural nerve revealed a mild loss of myelinated fibers with thinning of the myelin. These findings and the clinical features confirmed the diagnosis of AMN. MRI in SE2000/40 scans at age 34 disclosed areas of high signal in the bilateral internal capsules.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:[Striatal involvement on MRI in adrenomyeloneuropathy]. 165 65

To determine left ventricular diastolic properties in patients with familial amyloid polyneuropathy, 23 patients were studied by digitized M-mode echocardiography and were compared with 15 age-matched normal subjects. None of the patients had restrictive ventricular physiology and all but two showed normal left ventricular fractional shortening. Both the normalized peak rate of diastolic increase in left ventricular internal dimension and the normalized peak rate of diastolic thinning of posterior wall were significantly lower in patients than in normal subjects (2.0 +/- 0.8 vs 3.0 +/- 0.4 sec-1; p less than 0.001, and 2.5 +/- 1.2 vs 5.8 +/- 1.0 sec-1; p less than 0.001, respectively). The left ventricular isovolumic relaxation time in patients was 91.5 +/- 22.2 msec, compared with 64.0 +/- 2.6 msec in normal subjects (p less than 0.001). Of the 18 patients without clinical evidence of overt heart disease, 12 had normal ventricular wall thickness and normal fractional shortening, but 10 of the 12 exhibited some abnormalities in diastolic properties. In addition, indexes of diastolic function were significantly related to ventricular wall thickness alone. These findings indicate that left ventricular diastolic abnormalities precede the development of clinically overt heart disease, ventricular wall thickening, and systolic dysfunction and may be related to intramyocardial amyloid infiltration with resultant fibrosis in patients with familial amyloid polyneuropathy.
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PMID:Computerized M-mode echocardiographic assessment of left ventricular diastolic function in patients with familial amyloid polyneuropathy. 233 31

We report two siblings who presented with non-progressive marked sensory ataxia associated with arthrogryposis multiplex congenita (AMC). Deep tendon reflexes and H reflex were completely absent, but F waves were preserved. The sensory nerve conduction studies indicated the presence of relatively mild sensory polyneuropathy. The conventional somatosensory evoked potentials (SEPs) showed mildly prolonged latency for both the peripheral and cortical responses, suggesting a slowed conduction through the peripheral as well as central pathway. However, the 'proprioceptive SEPs' were absent, in conformity with complete loss of joint sense. Sural nerve biopsy revealed only mild thinning of myelin in the younger sister but was entirely normal in her brother. Taken together with the characteristic electrophysiological findings, the symptoms were considered to be due to predominant involvement of a selective population of somatosensory ganglions. The present cases showed no progression of the neurological deficit what-so-ever since birth, which strongly suggests a developmental anomaly or aplasia of a limited population of peripheral sensory neurons.
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PMID:A new form of congenital proprioceptive sensory neuropathy associated with arthrogryposis multiplex. 1559 29

A 46-year-old man experienced numbness and muscle weakness in the distal portions of both hands, which progressed over following three months. Neurological examination showed mild muscle weakness only in distal arms, hypoflexia or areflexia, and hypesthesia in glove and stocking distribution. Motor conduction study revealed markedly prolonged distal latency and abnormal temporal dispersion. Sensory nerve potentials were reduced or could not be recorded. Histopathlogical findings of the sural nerve showed several nerve fibers with thinning myelin sheath and mild reduction of myelinated fibers. These results suggested the diagnosis of chronic inflammatory demyelinating polyneuropathy (CIDP). Two weeks after intravenous immunoglobulin therapy, neurological deficits rapidly improved and electrophysiological abnormalities were also ameliorated. Thereafter, there was no clinical deterioration for two years without further treatment. Our patient suggested that immunomodulating treatment is needed for stopping the initial progression of neurological deficits, but maintenance therapy is not always necessary for keeping the remitting state in distal variant of CIDP.
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PMID:[Good response to intravenous immunoglobulin therapy in sensory dominant distal variant of chronic inflammatory demyelinating polyneuropathy]. 2182 6