Relationship of altered glutamate receptor subunit mRNA expression to acute cell loss after spinal cord contusion

Alterations in the expression of ionotropic glutamate receptors (GluR) contribute to neuronal loss after brain ischemia and epilepsy. In order to determine whether altered expression of GluR subunits might contribute to cell loss after spinal cord injury (SCI), we performed a time course study of subunit mRNA expression using quantitative in situ hybridization. Expression was studied in ventral horn motor neurons (VMN) and glia in adjacent ventral white matter at 15 min and 4, 8, and 24 h after SCI in tissue sections 4 mm rostral and caudal to the injury epicenter. We found that the AMPA subunit GluR2 was significantly down-regulated in VMN at 24 h, but not at the earlier times examined, although half the loss of VMN in these locations occurs by 8 h after injury. No changes in the normal expression of GluR2 or GluR4 were found in white matter where glial loss occurs after SCI. NMDA subunits NR1 and NR2A were significantly and rapidly up-regulated in VMN after SCI, but only caudal to the lesion site, while VMN loss is similar rostral and caudal to the epicenter. Thus, the temporal pattern of AMPA and the spatial pattern of NMDA subunit expression changes were distinct from the pattern of VMN loss after SCI. We conclude that altered GluR subunit expression after SCI is unlikely to be involved in secondary cell loss and instead may be involved with plasticity and reorganization of the injured spinal cord.

Cyclophosphamide attenuates the degenerative changes induced by CSF from patients with amyotrophic lateral sclerosis in the neonatal rat spinal cord

Our earlier studies have shown that cerebrospinal fluid (CSF) of patients with amyotrophic lateral sclerosis (ALS), when intrathecally injected into the neonatal rats, produces an aberrant phosphorylation of neurofilaments (NF) in the ventral horn neurons and reactive astrogliosis in the spinal cord. We wanted to investigate the effect of cyclophosphamide in the spinal cords of neonatal rats exposed to ALS-CSF. A single dose (5 microg in 5 microl saline) of cyclophosphamide was injected, 24 h after the administration of CSF samples from ALS and non-ALS neurological patients into the spinal subarachnoid space of 3-day-old rat pups. Rats were sacrificed after a period of 24 h, and stained with antibodies against the phosphorylated NF (SMI-31 antibody) and glial fibrillary acidic protein (GFAP). Cyclophosphamide treatment resulted in a 50% decrease in the number of SMI-31 stained neuronal soma in ventral horns of spinal cords of ALS-CSF exposed rats. This was accompanied by a decrease in the number of GFAP immunoreactive astrocytes. Furthermore, lactate dehydrogenase (LDH) activity was also decreased significantly, following cyclophosphamide treatment. These results suggest that cyclophosphamide could exert a neuroprotective effect against the neurotoxic action of factor(s) present in the ALS-CSF.

Dorsal horn lesion resulting from spinal root avulsion leads to the accumulation of stress-responsive proteins

The aim of this study was to demonstrate acute to subacute molecular episodes in the dorsal horn following root avulsion using immunohistochemical methods with the markers for synapses, astrocytes and such stress-responsive molecules as heat shock proteins (Hsps) and p38 MAP kinase (p38). Among them, Hsp27 was accumulated selectively in the injured substantia gelatinosa 24 h after avulsion injury. The localization of Hsp27 in astrocytes within the substantia gelatinosa was confirmed by the double immunofluorescence method using anti-Hsp27 antibody and either anti-synaptophysin antibody or anti-glutamine synthetase antibody and by immunoelectron microscopy for Hsp27. The pattern of Hsp27 expression subsequently changed from glial pattern to punctate pattern by 7 days. Immunoelectron microscopy revealed that the punctate pattern in the subacute stage corresponded to distal parts of the astrocytic processes. Hsp27 immunoreaction was decreased 21 days after root avulsion. In the distal axotomy model, Hsp27 was accumulated later in the ipsilateral dorsal horn in a punctate pattern from 7 days after the axotomy. Phosphorylation of p38 was detected in microglia in the dorsal horn following both avulsion and axotomy. Substance P was slightly decreased in the injured substantia gelatinosa in both the avulsion and axotomy models around 14-21 days. We conclude that Hsp27 is a useful marker for demonstrating dorsal horn lesions following avulsion injury and that avulsion injury may induce Hsp27 in the dorsal horn more rapidly than distal axotomy.

Arthrogryposis and multicystic encephalopathy after acute fetal distress in the end stage of gestation

The natural history of the rare association "multicystic encephalopathy-arthrogryposis" was traced in a fetus carefully followed after artificial insemination. The fetus exhibited normal viability and brain morphology up to the 32nd week. At 36 weeks, active movements diminished and at 37 weeks, hydramnios and signs of fetal distress led to cesarean section. The infant presented with severe arthrogryposis of the limbs and spine, but not with the other elements of a long-lasting akinesia. US showed multicystic encephalopathy. Both the clinical and the neuropathological findings established that multicystic encephalopathy was neither the cause nor the sequential consequence of the fetal akinesia, but the result of a recent diffuse, acute malacic process that also involved the anterior horn cells. Acute fetal distress, responsible for major ischemic damage to CNS but compatible with fetal survival, remains an obscure condition which allows for the development of severe arthrogryposis in a few weeks.

Superior muscle reinnervation after autologous nerve graft or poly-L-lactide-epsilon-caprolactone (PLC) tube implantation in comparison to silicone tube repair

Recovery after peripheral nerve injury depends not only on the amount of reinnervation, but also on its accuracy. The rat sciatic nerve was subjected to an 8 mm long gap lesion repaired either by autograft (AG, n = 6) or tubulization with impermeable silicone tube (SIL, n = 6) or permeable tube of poly-L-lactide-epsilon-caprolactone (PLC, n = 8). Recordings of the compound muscle action potential (CMAP) from gastrocnemius (mGC), tibialis anterior (mTA) and plantar (mPL) muscles were performed 90 days after injury to assess the amount of muscle reinnervation. The CMAP amplitude achieved in mGC, mTA and mPL was similar in after nerve autograft (39%, 42%, 22% of control values) and PLC tube implantation (37%, 36%, 24%) but lower with SIL tube (29%, 30%, 14%). The nerve fascicles projecting into each of these muscles were then transected and retrograde tracers (Fluoro Gold, Fast Blue, DiI) were applied to quantify the percentage of motoneurons with single or multiple branches to different targets. The total number of labeled motoneurons for the three muscles did not differ in autografted rats (1186 +/- 56; mean +/- SEM) with respect to controls (1238 +/- 82), but was reduced with PLC tube (802 +/- 101) and SIL tube (935 +/- 213). The percentage of neurons with multiple projections was lower after autograft and PLC tube (6%) than with SIL tube (10%). Considering the higher CMAP amplitude and lower number of neurons with multiple projections, PLC nerve conduits seem superior to SIL tubes and a suitable alternative to autografts for the repair of long gaps.

Delaying caspase activation by Bcl-2: A clue to disease retardation in a transgenic mouse model of amyotrophic lateral sclerosis

Molecular mechanisms of apoptosis may participate in motor neuron degeneration produced by mutant copper/zinc superoxide dismutase (mSOD1), the only proven cause of amyotrophic lateral sclerosis (ALS). Consistent with this, herein we show that the spinal cord of transgenic mSOD1 mice is the site of the sequential activation of caspase-1 and caspase-3. Activated caspase-3 and its produced beta-actin cleavage fragments are found in apoptotic neurons in the anterior horn of the spinal cord of affected transgenic mSOD1 mice; although such neurons are few, their scarcity should not undermine the potential importance of apoptosis in the overall mSOD1-related neurodegeneration. Overexpression of the anti-apoptotic protein Bcl-2 attenuates neurodegeneration and delays activation of the caspases and fragmentation of beta-actin. These data demonstrate that caspase activation occurs in this mouse model of ALS during neurodegeneration. Our study also suggests that modulation of caspase activity may provide protective benefit in the treatment of ALS, a view that is consistent with our recent demonstration of caspase inhibition extending the survival of transgenic mSOD1 mice.

Sustained induction of heme oxygenase-1 in the traumatized spinal cord

Oxidative stress contributes to secondary injury after spinal cord trauma. Among the consequences of oxidative stress is the induction of heme oxygenase-1 (HO-1), an inducible isozyme that metabolizes heme to iron, biliverdin, and carbon monoxide. Here we examine the induction of HO-1 in the hemisected spinal cord, a model that results in reproducible degeneration in the ipsilateral white matter. HO-1 was induced in microglia and macrophages from 24 h to at least 42 days after injury. Within the first week after injury, HO-1 was induced in both the gray and the white matter. Thereafter, HO-1 expression was limited to degenerating fiber tracts. HSP70, a heat shock protein induced mainly by the presence of denatured proteins, was consistently colocalized with HO-1 in the microglia and macrophages. This study to demonstrates long-term induction of HO-1 and HSP70 in microglia and macrophages after traumatic injury and an association between induction of HO-1 and Wallerian degeneration. White matter degeneration is characterized by phagocytosis of cellular debris and remodeling of surviving tissue. This results in the metabolism, synthesis, and turnover of heme and heme proteins. Thus, sustained induction of HO-1 and HSP70 in microglia and macrophages suggests that tissue degeneration is an ongoing process, lasting 6 weeks and perhaps even longer.

Hypoglycaemic neuropathy in diabetic BB/Wor rats treated with insulin implants affects ventral root axons but not dorsal root axons

It is believed that hyperglycaemia underlies diabetic neuropathy. However, low blood glucose values may also cause pathological changes in peripheral nerves and in neuronal perikarya. This study examined spinal roots, dorsal root ganglia and the ventral horn at the segmental level L5 in long-term insulin-treated eu-/hypoglycaemic diabetic rats with an obvious plantar nerve pathology. The purpose was to determine whether hypoglycaemic neuropathy affects sensory and/or motor neurons at root and/or perikaryal levels. Electron microscopic examination of dorsal roots from eu-/hypoglycaemic rats showed a normal qualitative morphology and normal numbers of unmyelinated and myelinated axons. In ventral roots the picture varied. Whereas two rats exhibited an essentially normal morphology, three rats presented moderate or marked signs of pathology such as clusters of small and medium-sized myelinated axons, medium-sized myelinated axons with abnormally thin sheaths, large unmyelinated axons and signs of past or ongoing axonal degeneration. Light microscopic examination of the L5 dorsal root ganglion and ventral horn showed a qualitatively normal picture in eu-/hypoglycaemic rats and the mean number of large ventral horn neurons per section was normal. These results suggest that the type of eu-/hypoglycaemia examined here affects ventral root axons but not dorsal root axons, that the degree of ventral root pathology is variable and that sensory and motor neuron perikarya do not appear to be affected.

iNOS and nitrotyrosine immunoreactivity in amyotrophic lateral sclerosis

We carried out an immunohistochemical investigation of the spinal cords of 15 patients with sporadic amyotrophic lateral sclerosis (ALS), using antibodies to inducible nitric oxide synthase (iNOS) and nitrotyrosine; our purpose was to search for a possible role of increased oxidative damage in the motor system that may contribute to the neurodegenerative process in this disease. Specimens from 16 patients without any neurological disease served as controls. In the controls, normal-appearing neurons and their dendrites were negatively immunostained for iNOS. In the ALS patients, most of normal-appearing anterior horn neurons did not show iNOS immunoreactivity either in the perikarya or in their dendrites. However, many of the degenerated neurons showing central chromatolysis or simple atrophy demonstrated focally or diffusely positive iNOS immunoreactivity within the perikarya and their neuronal processes. In the neuropil of the anterior horns, the reactive astrocytes were more intensely immunostained for iNOS as compared with the controls. Some of the swollen proximal axons (spheroids) were focally or diffusely immunostained by the antibody. The corticospinal tracts demonstrated positive iNOS immunoreactivity of proliferated reactive astrocytes. The immunostaining pattern of nitrotyrosine in the anterior horn neurons of the spinal cord was similar to that of iNOS. These findings suggest that selective nitric oxide-mediated oxidative damage in the motor system plays a part in the pathomechanism of the neuronal degeneration in the spinal cord of sporadic ALS.

Hereditary motor and sensory neuropathy with absence of large myelinated fibers due to absence of large neurons in dorsal root ganglia and anterior horns, clinically associated with deafness, mental retardation, and epilepsy (HMSN-ADM)

Hereditary motor and sensory neuropathy (HMSN) with autosomal recessive inheritance represents a genetically heterogeneous group of disorders with variable clinical, pathologic and electrophysiologic manifestations. A new variant of autosomal recessive HMSN, clinically defined by sensorimotor polyneuropathy associated with deafness and mental retardation, has recently been described. We report on the first autopsy case with this type of HMSN: a girl of non-consanguineous parents with a presumably autosomal recessive type of motor and sensory neuropathy clinically associated with deafness, mental retardation, and epilepsy. The autopsy showed complete absence of large myelinated fibers in peripheral motor and sensory nerves corresponding to a lack of large neurons in dorsal root ganglia and anterior horns of the spinal cord, moderate neurogenic muscle atrophy, and nearly complete absence of neurons in the dentate nucleus of the cerebellum. Molecular genetic analyses in our case revealed neither genetic alterations in the survival motor neuron gene nor in the PMP-22 gene.

White matter injury in spinal cord ischemia: protection by AMPA/kainate glutamate receptor antagonism

BACKGROUND AND PURPOSE

Spinal cord ischemia is a serious complication of surgery of the aorta. NMDA receptor activation secondary to ischemia-induced release of glutamate is a major mechanism of neuronal death in gray matter. White matter injury after ischemia results in long-tract dysfunction and disability. The AMPA/kainate receptor mechanism has recently been implicated in white matter injury.

METHODS

We studied the effects of AMPA/kainate receptor blockade on ischemic white matter injury in a rat model of spinal cord ischemia.

RESULTS

Intrathecal administration of an AMPA/kainate antagonist, 6-nitro-7-sulfamoyl-(f)-quinoxaline-2, 3-dione (NBQX), 1 hour before ischemia reduced locomotor deficit, based on the Basso-Beattie-Bresnahan scale (0=total paralysis; 21=normal) (sham: 21+/-0, n=3; saline: 3.7+/-4.5, n=7; NBQX: 12. 7+/-7.0, n=7, P<0.05) 6 weeks after ischemia. Gray matter damage and neuronal loss in the ventral horn were evident after ischemia, but no difference was noted between the saline and NBQX groups. The extent of white matter injury was quantitatively assessed, based on axonal counts, and was significantly less in the NBQX as compared with the saline group in the ventral (sham: 1063+/-44/200x200 microm, n=3; saline: 556+/-104, n=7; NBQX: 883+/-103, n=7), ventrolateral (sham: 1060+/-135, n=3; saline: 411+/-66, n=7; NBQX: 676+/-122, n=7), and corticospinal tract (sham: 3391+/-219, n=3; saline: 318+/-23, n=7; NBQX: 588+/-103, n=7) in the white matter on day 42.

CONCLUSIONS

Results indicate severe white matter injury in the spinal cord after transient ischemia. NBQX, an AMPA/kainate receptor antagonist, reduced ischemia-induced white matter injury and improved locomotor function.

Ubiquitin-immunoreactive skein-like inclusions in the neostriatum are not restricted to amyotrophic lateral sclerosis, but are rather aging-related structures

We examined the presence of ubiquitin-immunoreactive skein-like inclusions (SLI) in the neostriatum and spinal cord in normal individuals and patients with different neurodegenerative diseases. Ubiquitin-immunoreactive SLI in the neostriatum were observed both in the normal individuals and in the patients with a variety of neurodegenerative diseases. In particular, SLI were frequently seen in normal aged subjects and certain neurodegenerative diseases, such as progressive supranuclear palsy and myotonic dystrophy. In contrast, the occurrence rate of SLI in cases with Pick's disease and multiple system atrophy tended to decrease. On the other hand, SLI in the spinal anterior horn were detected in cases of amyotrophic lateral sclerosis, but not in any cases with other neurodegenerative diseases. SLI in the neostriatum were also identifiable using phosphotungstic acid-hematoxylin and Gomori trichrome staining. Ubiquitin immunoelectron microscopy demonstrated that the SLI in the neostriatum corresponded to bundles of filaments. These features of SLI in the neostriatum were quite similar to those of intracytoplasmic rod-like inclusions (RLI) in the large neurons of caudate nucleus, which were first described by Kojima and Ogawa in 1974. Our findings indicate that SLI in the neostriatum are ubiquitin-related structures whose occurrence increases by aging, and less frequently accompany several neurodegenerative diseases, and are identical to at least some RLI.

Immunohistochemical demonstration of spinal ventral horn cells involvement in a case of "myoclonus epilepsy with ragged red fibers" (MERRF)

OBJECTIVE

To detect mitochondrial lesions in the spinal cord from an autoptic case of myoclonus epilepsy with ragged-red fibers (MERRF) that harbored the A8344G mutation and was deemed to be free of pathological abnormalities in the spinal cord after conventional post-mortem examination.

MATERIALS AND METHODS

Antibodies against subunits of complex III and IV of the respiratory chain were used to perform immunohistochemical analysis on cervical, thoracic and lumbar sections of the spinal cord from the case of MERRF and from controls. Immunostaining was carried out by the avidin-biotin peroxidase complex (ABC) method.

RESULTS

A selective decreased expression of subunit II of cytochrome c oxidase (COX-II) was found in all spinal cord sections from the patient.

CONCLUSIONS

The immunohistochemical demonstration of mitochondrial lesions in the spinal ventral horn cells from this case with MERRF seems to be consistent with the results of many genetic studies pointing to a high and homogeneous distribution of mutant mtDNA in different neuronal populations of patients with this disease. The use of these immunological probes in the study of mitochondrial encephalomyopathies can increase both the resolution and the specificity of morphological observations in the central nervous system (CNS).

Glutamate release and neuronal injury after intrathecal injection of local anesthetics

High concentrations of local anesthetics are neurotoxic, but the mechanism for this neurotoxicity is obscure. Here, we report increased concentrations of glutamate in the cerebrospinal fluid after intrathecal injections of high concentrations of tetracaine (a local anesthetic). The peak concentrations of glutamate after administration of 1%, 2%, and 4% tetracaine were 4-fold, 6-fold, and 10-fold higher than baseline values, respectively. Animals in the 1% group were all neurologically normal one week after tetracaine injection. In the group receiving 4%, no animal was able to hop and vacuolation of the white matter and/or central chromatolysis of the motor neurons were observed. Because high concentrations of glutamate are known to be neurotoxic, our results may provide some insight into the mechanisms for neurotoxicity of intrathecal local anesthetics.

Fragmentation of the Golgi apparatus of the anterior horn cells in patients with familial amyotrophic lateral sclerosis with SOD1 mutations and posterior column involvement

The Golgi apparatus (GA) of the anterior horn cells in the spinal cord was examined by immunohistological methods with an antibody against the MG-160 protein, a conserved intrinsic membrane sialoglycoprotein of the medial cisternae of the GA, in three patients with familial amyotrophic lateral sclerosis (FALS) with posterior column involvement. Large motor neurons in the anterior horns were markedly reduced in number and 10 of total 14 remaining large motor neurons showed fragmentation and a reduction in the number of the elements of the GA. The fragmentation of the GA was identical to that previously reported in motor neurons of the spinal cord and motor cortex from patients with sporadic ALS and in transgenic mice expressing the G93A mutation of the gene encoding the Cu/Zn superoxide dismutase months before the onset of paralysis. This is the first report of fragmented GA of the anterior horn cells in patients with FALS with posterior column involvement. The findings suggest that the GA is a common target in the neuronal degeneration in sporadic and FALS.

Immunolocalization of NAIP in the human brain and spinal cord

The neuronal apoptosis inhibitory protein (NAIP) is known to have anti-apoptotic functions, and its gene is often mutated in severe cases of spinal muscular atrophy (SMA), a disease characterized by motor neuron degeneration. In this study, we examined the distribution of the endogenous NAIP protein in normal human spinal cord and brain tissue by using a polyclonal antibody against NAIP. Immunohistochemical staining demonstrated that NAIP is strongly expressed in anterior horn and motor cortex neurons of normal brains, and it is not altered in the remaining motor neurons of patients with amyotrophic lateral sclerosis (ALS). NAIP is also located in human fetal neurons and in adult choroid plexus cells. These results suggest that the anti apoptotic molecule NAIP may be important in motor neurons, but it specifically does not appear to be altered in ALS.

Numerous conglomerate inclusions in slowly progressive familial amyotrophic lateral sclerosis with posterior column involvement

A 59-year-old woman with slow progression of the loss of motor function and predominant lower motor manifestation during a 14-year period showed familial amyotrophic lateral sclerosis (fALS) with posterior column involvement, neuropathologically. Conglomerate inclusions (CIs) were observed in the remaining neurons in various areas, including the spinal anterior horn, posterior horn, Clark's column, accessory cuneate nucleus, tegmental reticular formation, motor nucleus of the trigeminal nerve, nucleus of the facial nerve, hypoglossal nucleus, medial nucleus of the thalamus, dentate nucleus, and motor cortex (Betz cells). Immunohistochemically, it was newly identified that the CIs showed marked immunoreactions with antibodies to phosphorylated and non-phosphorylated neurofilaments and to 64, 120, and 200 kD neurofilaments. The CIs were partially immunoreactive with the anti-ubiquitin antibody, although they reacted only weakly (or not at all) with anti-Cu/Zn superoxide dismutase (SOD1) antibody. Ultrastructurally, the CIs were comprised of neurofilaments. These data suggest that this case might have been different from an example of fALS with Ile 113 Thr mutation in the SOD1 gene.

[An autopsy case of motoneuron disease with dementia of long duration]

An autopsy case of MND with dementia, 67 years old, man, was reported. The behavioral disturbance appeared at 61 years old, and was followed by the upper limb weakness and respiratory failure. He had remained on a respirator for 56 months. The total duration of the disease was 74 months, which was far longer than mean duration of the cases previously reported, 25-30 months. The pathological findings were about essentially identical to those mentioned before, such as cortical alterations in temporal and frontal lobes, neuronal loss with gliosis in amygdaloid body and substantia nigra, and loss of lower motoneurons in anterior horn of spinal cord and in the several motor cranial nerve nuclei. There were several Bunina bodies in the remnant lower motoneurons, but no changes in the pyramidal tracts or loss of Betz cells in the precentral gyrus. Intracytoplasmic ubiquitin-immunopositive inclusions in the granule cells of hippocampal dentate gyrus were also encountered, but the number of which did not increased, compared to the preceding data. There may be frequently little correlation between the disease duration and the number of such inclusions. The regional alteration in the intermediate zone between subiculum and entorhinal cortex was revealed also at the level of the splenium of corpus callosum. It has been reported that such parahippocampal lesion may initiate at the anterior part of temporal lobe and become undiscernible at more posterior level than the lateral geniculate body. The formation of such parahippocampal lesion may be concerning with the length of disease duration. In addition, there were numerous senile plaques, diffuse or neuritic type only in the parietal lobe cortex without any other changes.

Increased expression of growth-associated protein 43 on the surface of the anterior horn cells in amyotrophic lateral sclerosis

This study examined axonal terminal alterations in the anterior horn of amyotrophic lateral sclerosis (ALS) patients. An antibody against growth-associated protein 43 (GAP43), a phosphoprotein which is expressed in elongating terminals of neurites, was employed for immunohistochemical staining. Lumbar spinal cords taken at autopsy from five ALS patients and from six control adults were examined. In control patients, there were numerous GAP43-positive granules diffusely dispersed throughout the anterior horn neuropil, and individual large anterior horn cells (AHCs) showed numerous tiny immunoreactive granules and small dots on the surface. A small number of AHCs showed dense accumulation of GAP43 immunoreactivity on the surface of the cell body and proximal processes. In all ALS patients, similar accumulation of GAP43 immunoreactivity was seen on the surface of a large number of remaining AHCs. Statistical analysis revealed a significant increase in number of AHCs with such accumulation in ALS patients. These results suggest that during the ALS disease process there may be plastic alterations or a compensatory mechanism of the axonal terminals located on the surface of some AHCs for ongoing anterior horn presynaptic terminal degeneration.

Multifocal polyradiculoneuropathy and carcinoma of the thymus

We studied a patient with polyradiculoneuropathy with anaplastic carcinoma of the thymus. Motor manifestations dominated. Postmortem examinations indicated that the primary changes were in the spinal nerve roots, peripheral nerves and, possibly, the spinal anterior horn cells. The posterior funiculi and posterior root ganglia were also affected, implying multifocal and multiphasic degeneration. This unusual polyradiculoneuropathy is a form of carcinomatous neuropathy.

[Subacute sensory neuronopathy with signs of involvement of anterior horn cells in a patient with small cell lung carcinoma (case report)]

A 55 years old woman with small-cell lung carcinoma is described. Ten months after the diagnosis was established, subacute sensory neuronopathy with the signs of involvement of anterior horn cells (confirmed by EMG exam) occurred. Since neurological symptoms appeared at the time when anti-cancer treatment was ceased, the diagnosis of paraneoplastic lesion peripheral nervous system was established. Biopsy of sural nerve obtained 3 months after the onset of neurological signs showed nearly complete loss of normal looking myelinated fibers due to the process of axonal degeneration with relatively better preserved unmyelinated fibers. The patient died after 1 year and 2 months from the beginning of the disease because of metastatic tumours in the brain.

Rapid onset transverse myelitis in adolescence: implications for pathogenesis and prognosis

Five adolescents with transverse myelitis were reviewed. All presented with a rapid onset paralysis of the lower limbs and impairment of bladder control. The maximum disability developed between 10 minutes and six hours. There was no history of trauma, asthma, or prodromal illness. Investigations failed to demonstrate a vascular cause. Extensive spinal cord abnormalities were observed on magnetic resonance imaging. Electrophysiological investigations, performed in four cases, were all consistent with anterior horn cell damage. In all five adolescents there was poor recovery. The underlying pathogenesis of this rapid onset condition remains a subject of debate. Similarities with both transverse myelitis and fibrocartilaginous emboli are evident, widening the spectrum of conditions within the transverse myelitis umbrella. These observations suggest that in rapid onset "transverse myelitis" the combination of extensive hyperintensity on spinal cord neuroimaging with electrophysiological evidence of anterior horn cell involvement might have adverse prognostic significance.

Pathological changes of the spinal cord in centenarians

In order to study the changes that occur in the spinal cords of the aged, 19 centenarian spinal cords from two men and 17 women (age range, 100-116 years at death; mean, 103 years) were pathologically examined. Cross-sections at each segmental level of the 19 autopsied spinal cords were examined for histopathological changes. The cross-sectional area and flattening ratio at the level of the C7 segment were measured. The size of the cords had some negative correlation with age, but the individual variation was considerably large. Among the 19 centenarians, macroscopic anteroposterior flattening appeared in the lower cervical cords in six individuals. In these cases, various degrees of neuron loss were observed in the anterior horn. White matter degeneration appeared frequently, especially in the posterior column. In 12 cases, myelin loss in the fasciculus of Goll at the cervical level was observed. The degeneration of the fasciculus of Goll was considered to be upward wallerian degeneration secondary to posterior root damage at the lumbosacral level. These changes seemed to be produced by disorders in the spinal canal or surrounding tissue, such as cervical spondylosis, degeneration of the intervertebral disk and spinal canal stenosis. Argyrophilic structures such as neurofibrillary tangles and neuropil threads were observed in 16 cases; however, this incidence was less than in the brain. Medial thickening of the anterior spinal artery was found in four cords. Amyloidangiopathy was noted in only one cord. Necrosis and hemorrhage due to vascular disturbance were not found.