Joint International SILACO, SICCMII, ISASS Symposium as a Model for a Collaborative Framework to Create Literature on Advances in Spine Surgery, Patient Care, and Policy.

International collaborations can be the key to overcoming innovation implementation hurdles. The authors report on a joint symposium between the International Society For The Advancement of Spine Surgery (ISASS) and La Sociedad Iberolatinoamerica de Columna (SILACO), and La Sociedad Interamericana de Cirurgia de columna de Minima invasión (SICCMII) aimed at improving joint surgeon education programs. The symposium highlighted that patient-related spine care issues are similar across geographical, cultural, and language barriers.

The evolution of an experimental distal motor axonopathy. Physiological studies of changes in neuromuscular transmission caused by cycloleucine, an inhibitor of methionine adenosyltransferase.

Cycloleucine (CL), a synthetic amino acid is known to cause degeneration of motor nerve terminals. This paper describes the changes in neuromuscular transmission, the morphology of motor end-plates and the responses of muscle spindles after a single dose of CL was administered to weanling and adult mice. Animals were allowed to survive for between 12 h and 7 days.

Induction of beta (A4)-amyloid in primates by injection of Alzheimer's disease brain homogenate. Comparison with transmission of spongiform encephalopathy.

Amyloid plaques, associated with argyrophilic dystrophic neurites, and cerebral amyloid angiopathy (CAA), but no neurofibrillary tangles, were found in the brains of three middle-aged marmoset monkeys that had been injected intracerebrally (ic) 6-7 yr earlier with brain tissue from a patient with early-onset Alzheimer's disease. Such changes were not found in the brains of three age-matched control marmosets. Immunochemically the amyloid plaques and CAA stained with antibody to beta (A4)-protein.

Mitochondrial DNA mutation underlying Leigh's syndrome: clinical, pathological, biochemical, and genetic studies of a patient presenting with progressive myoclonic epilepsy.

An 18-year-old male patient presented with clinical and radiological evidence of Leigh's syndrome (LS), having developed progressive myoclonic epilepsy and ataxia 11 years previously. Muscle biopsy showed cytochrome oxidase deficiency but no ragged red fibres. Autopsy confirmed the diagnosis of LS; there was additional degenerative change in the cerebellum and dentate and olivary nuclei, and an axonal peripheral neuropathy.

Evidence for the experimental transmission of cerebral beta-amyloidosis to primates.

The brains of three marmosets (Callithrix jacchus) injected intracerebrally 6-7 years earlier with brain tissue from a patient with early onset Alzheimer's disease were found to contain moderate numbers of amyloid plaques with associated argyrophilic dystrophic neurites and cerebral amyloid angiopathy but no neurofibrillary tangles. The plaques and vascular amyloid stained positively with antibodies to beta (A4)-protein. The brains of three age-matched control marmosets from the same colony did not show these neuropathological features.

Experimental induction of beta-amyloid plaques and cerebral angiopathy in primates.

Moderate numbers of amyloid plaques with associated argyrophilic dystrophic neurites and cerebral amyloid angiopathy (CAA) but no neurofibrillary tangles (NFTs) were found in the brains of 3 middle-aged common marmosets (Callithrix jacchus) inoculated intracerebrally (i.c.) 6-7 years earlier with brain tissue from a patient with early onset Alzheimer's disease.

Creutzfeldt-Jakob disease and lyophilised dura mater grafts: report of two cases.

Two further cases of Creutzfeldt-Jakob disease (CJD) in association with cadaveric dura mater grafts are described. The clinical features of all such reported cases resemble more closely those of sporadic CJD, in contrast with kuru and the cases of CJD which have arisen after therapy with human pituitary-derived growth hormone. This observation may reflect the route of inoculation of the agent.

Dementia associated with a 216 base pair insertion in the prion protein gene. Clinical and neuropathological features.

We report the clinical and neuropathological findings in a patient with a 216 base pair insertion in the prion protein (PrP) gene. She died aged 57 years after a 2.5-year illness characterized by falls, axial rigidity, myoclonic jerks and progressive dementia.

Cerebral amyloid in human prion disease.

The clinical and neuropathological features of 21 patients with prion disease were reviewed with special reference to the morphology and immunoreactivity of cerebral amyloid. Six cases had a mutation at codon 102 of the prion protein (PrP) gene and in these the characteristic pathology was the formation of multicentric amyloid plaques which were stained with PrP antibody, whereas spongiform changes were absent in one and minimal in two. In one case, with a 216 base-pair insertion in the PrP gene, there was no spongiform encephalopathy (SE) but cerebellar amyloid was a prominent feature of the pathology.

Brown-Vialetto-Van Laere syndrome.

The clinical and pathological findings of a male with the Brown-Vialetto-Van Laere syndrome are described. This rare and fatal affection of the nervous system involves mainly the brain stem with the prominent and early manifestation of sensorineural deafness. Increased awareness and documentation of this disorder has added information on the mode of inheritance.

Distal motor axonopathy and central nervous system myelin vacuolation caused by cycloleucine, an inhibitor of methionine adenosyltransferase.

Cycloleucine (CL), an inhibitor of methionine adenosyltransferase, has previously been used to produce an experimental model of subacute combined degeneration of the spinal cord. A re-investigation of its effects on the morphology of the nervous system and on brain concentrations of methionine and S-adenosylmethionine (SAM) was undertaken. Cycloleucine was administered as a single dose intraperitoneally (2 mg/g body weight) to young mice aged 21 d and adults aged 6 or 10 wks.

A re-appraisal of a case of persistent global amnesia following right temporal lobectomy: a clinico-pathological study.

We report a reappraisal of patient NT who became severely amnesic after a right temporal lobectomy for intractable epilepsy (DINSDALE et al., Neuropsychologia 1, 287, 1964 [6]). Histological examination, albeit incomplete, indicated that there was no abnormality in the resected temporal lobe.

Creutzfeldt-Jakob disease in recipients of human growth hormone in the United Kingdom: a clinical and radiographic study.

In the past 3 years there have been five further cases, in addition to one case reported in 1985, of Creutzfeldt-Jakob disease in recipients of human growth hormone in the United Kingdom. The clinical findings of two of these cases are described, demonstrating a typical presentation with a predominantly cerebellar syndrome at onset which is not commonly a presenting feature of sporadic Creutzfeldt-Jakob disease. In one case a 99mTc hexamethylpropylenamine single photon emission tomographic scan showed marked impairment of tracer uptake in the basal ganglia and cerebral cortex at a time when the clinical picture was predominantly cerebellar.

Spongiform encephalopathy transmitted experimentally from Creutzfeldt-Jakob and familial Gerstmann-Sträussler-Scheinker diseases.

A comparison was made of the effects of experimental intracerebral inoculation into marmosets of brain homogenates from a case of Creutzfeldt-Jakob disease (CJD) and from a member of the Wo. family with cerebral amyloid and spongiform encephalopathy--the Gerstmann-Sträussler-Scheinker (GSS) syndrome. All the inoculated marmosets developed spongiform encephalopathy (SE) after incubation times of 20-23 months in the CJD group and 25-32 months in the GSS group.

End-plates, transmission and contractile characteristics of muscles without spindles in the hereditary sensory neuropathy of the Sprawling mouse.

In the mutant mouse Sprawling, a deficiency of sensory ganglion cells is associated with a failure of the development of spindles and tendon organs particularly affecting muscles of the hindleg. Electrophysiological and morphological investigations were made on nerve, muscle and the neuromuscular junction of soleus and extensor digitorum longus (EDL). It was found that the absence of sensory innervation had no effect on the development of muscle bulk, on the fibre diameters or on histochemical profiles.

Rating of the lesions in senile dementia of the Alzheimer type: concordance between laboratories. A European multicenter study under the auspices of EURAGE.

The study reported was intended to compare the impressions and analyses of investigators from 11 different laboratories on 2 slides, each from 6 cases with varying quantities of neuropathological change of the type found in Alzheimer's disease and normal ageing. The material came from 6 selected female patients over 75 years of age all of whom had been examined in detail and assessed by the Blessed Test Score. Two were severely demented, 2 mildly demented and 2 were considered to be normal.

Progressive medullary failure associated with neurofibrillary degeneration.

A clinicopathological report is presented of a British male, aged 59 years, who died after an illness of 10 years, manifested by progressive respiratory failure, ptosis, and dysphagia. At no time was there evidence of ophthalmoplegia, Parkinsonism or dementia. At necropsy the main finding was of neurofibrillary tangles in the neurons of the pontine and medullary reticular formation, with particularly severe involvement of the nucleus ambiguus, dorsal motor nucleus of the vagus and nucleus tractus solitarius.

Changes in denervated skeletal muscle of amiodarone-fed mice.

Prolonged dosing of mice with amiodarone produced a myopathy characterized by autophagic vacuolation and phospholipid inclusions. A previous morphological study had shown that amiodarone did not affect the rate of nerve regeneration after sciatic nerve crush. In the present study, reinnervation was assessed by the reappearance of miniature endplate potentials that confirmed that axonal regeneration and motor reinnervation was not affected by amiodarone.

Effects of phospholipase of Enhydrina schistosa venom on nerve, motor end-plate and muscle of the mouse.

Phospholipase A2 from Enhydrina schistosa (sea snake) venom was administered intravenously or intramuscularly to mice. The effects on the contractile responses and neuromuscular transmission were studied in soleus (a slow-twitch muscle) and extensor digitorum longus (e.d.

The mutant mdx: inherited myopathy in the mouse. Morphological studies of nerves, muscles and end-plates.

The mdx mutant mouse was first observed during a survey of genetic variations of pyruvate kinase in the mouse. Affected mice have high serum levels of this enzyme and although showing little disability they have widespread and severe muscle disease. Light and electron microscopy, muscle enzyme histochemistry and combined cholinesterase-silver impregnations were used for the study of affected and control animals aged 1 day to 1 year.

Sera from patients with motor neuron disease and associated paraproteinaemia fail to inhibit experimentally induced sprouting of motor nerve terminals.

IgG kappa paraproteinaemia was discovered in one patient with amyotrophic lateral sclerosis and one with chronic spinal muscular atrophy. Serum from these patients was injected into mouse muscles paralysed by botulinum toxin which is known to induce sprouting from motor nerve terminals. Daily injection of serum for 7 days failed to inhibit terminal sprouting.

Morphological abnormalities in myelinated nerve fibres caused by Leiurus, Centruroides and Phoneutria venoms and their prevention by tetrodotoxin.

Morphological changes in peripheral nerve caused by the venoms of the scorpions Leiurus quinquestriatus and Centruroides sculpturatus were compared with those caused by Phoneutria nigriventer spider venom. Both scorpion venoms are known to delay the inactivation of sodium currents, Centruroides venom also altering the voltage dependence of sodium gating. Venom was injected by means of a glass micropipette into the sciatic nerves of anaesthetized mice.

A quantitative study of intermediolateral column cells in motor neuron disease and the Shy-Drager syndrome.

The intermediolateral column neurons in the lateral horns of the grey matter of the thoracic spinal cord were counted in five patients who had died of motor neuron disease, two of the Shy-Drager syndrome and three of other neurological diseases not affecting the spinal cord or roots. The number of intermediolateral column cells in all the motor neuron disease cases was slightly reduced compared with the control cords, this difference being apparent both when the whole thoracic sympathetic outflow was assessed as well as its upper, middle and lower thirds. The difference, however, was not statistically significant.