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The authors report the anatomical and clinical findings observed in a case of alexia iwthout agraphia due to left posterior cerebral artery infarction, in which there were lesions of the occipital and thalamic regions, the splenium of the corpus callosum, and the hippocampus. They discuss, more particularly, the memory difficulties, and the objects naming trouble.

From a review of the literature it appears that only dopaminergic and cholinergic deficiencies are well established in the elderly. Other changes, still awaiting description and confirmation, are likely to consist of deficiency, overfunctioning or complex imbalance depending on the system involved. They will probably show that ageing of the brain begins at an early stage in life and that there is a need for considering not only very old people but transformation extending from birth to death. Meanwhile, studying cerebral mediators in healthy elderly subjects is a necessary prerequisite to studies of the brain in old patients with neuropsychiatric disorders.

A peripheral neuropathy has been reported in patients with chronic respiratory insufficiency due to chronic obstructive pulmonary disease (COPD). It is mainly characterized by axonal degeneration, secondary demyelination and abnormal endoneurial vessels. The pathogenesis of these lesions remains obscure. To investigate whether relationships exist between neuritic and vascular lesions, a qualitative and quantitative ultrastructural study was performed on nerve biopsies in 13 patients with chronic respiratory insufficiency due to COPD, and in 9 normal controls without pulmonary lesions. A computer-assisted multiple regression analysis taking into account clinical, electrophysiological, biological and morphometric parameters was performed. Statistically significant differences in the endoneurial structure of microvessels were: (1) thickening of the basement membrane; (2) narrowing of the lumen; (3) mural pericytic debris deposits, occurring in the COPD group. In the latter, hypercapnia correlated positively with nerve fibers lesions (P = 0.03) and endothelial area (P = 0.03). No correlations were found between age and other parameters. These findings highlight the fact that the microangiopathy in peripheral nerves in patients with COPD may be diffuse and essentially due to hypoxia and reduction in blood flow, as in diabetic neuropathy.

The authors describe an anatomical familial case of progressive infantile cerebral poliodystrophy (Alpers disease), in which the study of enzyme kinetics of hepatic pyruvate carboxylase revealed an abnormal graph reflecting a loss of activity of the enzyme with low concentrations of substrate, This is a new feature in the literature on Alpers disease, and possibly indicates one of the pathogenic mechanisms responsible in this disorder which remains mysterious, although its pathology has been clearly described.

The topographical distribution of neurons containing LHRH has been investigated in newborn hypothalamus using the peroxidase anti-peroxidase technique. In control subjects, LHRH immunoreactive (LHRH-IR) perikarya have been mainly observed essentially in the infundibular nucleus. The preoptic region displayed a moderate density of LHRH-IR cell bodies. High LHRH innervation was observed in the anterior hypothalamus in the lamina terminalis and in the mediobasal hypothalamus in the median eminence, and in the peri- and paraventricular regions. In sudden death infant syndrome, a comparable mapping was observed, except a low density in the mediobasal peri- and paraventricular areas.

After a classical neuropathological study assessing the diagnosis, the activity of the GABA synthetizing enzyme, glutamate decarboxylase (GAD), was assayed in 6 brain areas, in 8 cases of Parkinson's disease, 2 cases of idiopathic orthostatic hypotension and 9 control cases carefully matched. The activity of GAD is not impaired, as classically believed, in parkinsonian brains, particularly in substantia nigra and pallidum. This preservation would indicate the absence of lesion of GABAergic neurones in Parkinson's disease. In the cases of other Parkinsonian syndromes, the number of cases studied is too limited to allow any generality; but they are, however reported because of their rarity.

Three cases of septo-optic dysplasia are related in infants. A neurogenic diabetes insipidus and an central adrenocortical insufficiency is proved. An growth hormone deficiency is founded in one case. The other anterior pituitary functions are normal. The pneumo-encephalography with congenital absence of septum lucidum and the ophtalmologic anomalies are typical. The treatment is envisaged. In one case an autopsy sustains the radiologic aspect.

The study of catecholaminergic (CA) systems in the lower brain stem was undertaken in the infant. A method of indirect immunohistofluorescence using antibodies to tyrosine-hydroxylase (TH) was applied to five brains from infants whose deaths had no neurological cause; two brains were submitted to fully systematic investigation. A topographical and morphocytological analysis of the CA systems was carried out on horizontal serial sections. A neuronal map is shown presenting four bulbar and four pontine sections. The disposition of the main CA groups (i.e. A1, A2, locus coeruleus) was found to be consistent with the data provided by the literature concerning the human foetus and the adult. Topographic differences and peculiarities are emphasized in the infant. Mapping of phenylethanolamine N methyltransferase (PNMT) positive neurons was performed in one plane of section of mid-medulla. This technique might usefully be applied to the exploration of putative diseases of bulbopontine CA systems, such as the sudden infant death syndrome and central blood pressure disorders.

Neurotensin immunoreactive (NT-IR) neuronal perikarya are present in small numbers in the bed nucleus of the stria terminalis, lateral olfactory stria, substantia innominata, caudate nucleus and putamen of the human infant forebrain. Larger numbers of perikarya are present in the amygdala and related structures. NT-IR axons are present in the medial septal area, bed nucleus of the stria terminalis, caudate nucleus, putamen and amygdala. The cerebral cortex contains a rich network of NT axons with an accentuation in layer II. This network appears to be derived from bundles of axons which traverse the deep white matter from the thalamus.

Two familial and sporadic cases of amyloid neuropathy are reported. Nerve biopsies ultrastructural studies permit to involve endothelial and Schwann cells basement membranes into formation of amyloid. This classical notion was worth being recalled and specified. The purpose of amyloid formation is searched in a toxico-metabolic processus possibly in relation with observed demyelinating mechanism. The Schwann cell is at the cross of the cause and of its effect.

The authors report a fairly typical clinico-pathological case of acute hemorragic leucoencephalitis (A.H.L.E.). Both clinical and histological features appeared particularly acute. At autopsy a visceral evolving tuberculosis was diagnosed. Such an etiological circumstance has not been, apparently, reported in cases of A.H.L.E. published as such. Three other etiological circumstances were noticed: pyuria, treatment by cephalotin and treatment by gentamycine. The physiopathogenesis of A.H.L.E. remains obscure and will not be clarified before detailed immunological studies can be performed. But the disease is rare and brisk and diagnosis usually post-mortem.

CT scan in 4 patients with Marchiafava-Bignami's disease in its acute alcoholic form, who died after 12, 18, 30 and 50 days respectively, demonstrated large symmetrical bilateral hypodense areas in the hemispheric white substance. These areas were either widespread or more marked posteriorly, and were independent of the corpus callosum. Pathologic examination of the brains showed necrotic regions, often with cavities, or areas of demyelinization of the centrum ovale correlating with the hypodense areas as seen on CT scans. In two cases CT scan further showed regions of linear hypodensity in front of and medial to the frontal ventricular horns which could have corresponded to the corpus callosum necrosis found on the brain sections. CT scan can thus contribute to the diagnosis of Marchiafava-Bignami's disease.

The immunohistochemical distribution of TH and PNMT containing neuronal elements was investigated utilizing peroxidase anti-peroxidase methods in newborn control and sudden infant death syndrome (SIDS) brainstems. The TH immunoreactive neurons, within the medulla oblongata, displayed a similar distribution in both control and SIDS tissue. However, PNMT immunoreactive neurons seen in the dorsal part of the nucleus of tractus solitarius in control tissue were not observed in SIDS tissue. This alteration of adrenergic neurons in the dorsal part of NTS (region reported to be implicated in the control of blood pressure and respiration) could explain the cardiorespiratory disorders in SIDS.

In victims of Sudden Infant Death Syndrome, the activity of phenylethanolamine-N-methyltransferase was found to decrease in the nucleus retroambigu, the Kolliker-Fuse nucleus and the C 2 area of medulla, whereas a decrease in the dopamine-beta-hydroxylase activity was found only in the C 2 area. These results suggest a hypoactivity of adrenergic neurons in respiratory and cardiac centres in the Sudden Infant Death Syndrome.

Three cases of adult males with spastic paraparesis and adrenal insufficiency are reported. The adrenal insufficiency is primary and in one case associated with Leydig cell insufficiency. Ultrastructural examination of peripheral nerve revealed abnormal cytoplasmic inclusions in Schwann cells. A decrease in the percentage of linoleate to total fatty acids was found in the sera. A child with adrenoleucodystrophy and an adult with adreno myeloneuropathy were observed in the same family. It allows adrenomyeloneuropathy to be considered as an adult form of adrenoleucodystrophy.

The activity of Phenylethanolamine-N-Methyltransferase (PNMT) was assayed in 12 brain structures in a group of 8 chronic psychotics, a sub-group of 5 schizophrenics and a group of 7 normal controls. It was found significant decreased in substantia perforata posterior and nucleus accumbens. These two structures belong to the meso-limbic system. These data, therefore, suggest an inhibition of PNMT and/or an alteration of putative adrenergic neurons in the meso-limbic system, in schizophrenia.

The authors review 500 extemporaneous histopathological examinations done in a neurosurgical unit over a 16-month period. The following four questions are asked by the neurosurgeon: is there a tumor? is it a primary or secondary one? what variety is it? what is its degree of malignancy? The percentage of errors was respectively: 2 per cent, 2.2 per cent, 8.8 per cent and 7.4 per cent, or roughly, a percentage two times lower than in a series from the same laboratory done before the use of the low-temperature microtome. It especially seems that the tumoral variety is often determined accurately in meningiomas, neurinomas, medulloblastomas and craniopharyngiomas. In gliomas the variety is often more difficult to accurately affirm, and especially the "grade" of malignancy. The authors analyse the problems raised by the different types of tumors.

A case of chronic disabling sensory-motor polyradiculitis occurring in a female patient and followed up for 18 months is reported. Clinical findings were papilledema, hypertrichosis, abnormal pigmentation of the skin, generalized edema, and spontaneous cutaneous necrosis. The diagnosis of a plasmocytic dyscrasia to IgA Lambda was made at a late stage of the disease. There were no signs of a solitary plasmocytoma or of diffuse myeloma. At autopsy, there were mild lesions in the peripheral nervous system, but no plasmocytic infiltration or amylosis was seen on optical or electron microscopy. This case is similar to other clinical cases reported mainly by Japanese authors.

A further case of apparently primary sensorimotor neuropathy is reported. The patient, a 31-year-old man, developed the syndrome after a 4-year history of a solitary vertebral plasmocytoma revealed by post mortem examination. Circulating monoclonal immunoglobulin and specific anomalies on nerve biopsy were absent. The condition became progressively worse, with initial and predominant autonomic nervous system anomalies. After 3 years, contractures of the limbs and paravertebral muscles, with painful paroxysmal attacks suggestive of the stiff-man syndrome appeared. Pathology confirmed the severity of the root lesions with diffusion to the cranial nerves. Reflex tests could not be conducted but the semiologic characteristics and the efficacity of baclofen were distinctive of continuous muscle fiber activities reported in some peripheral neuropathies. This case was comparable to some reported ones of interneuron rigidity.

The authors report a clinically typical case of trichopoliodystrophy (Menkes' disease) ; Neuropathological studies showed classical alterations, particularly irregular thickenings of Purkinje cell dendrites, and some less usual modifications : presence of an ectopic neuronal layer in the cerebellar molecular layer, suggestive of Obersteiner cells stopped in their progression ; normal appearance of myelin and elastic structures of systemic arteries. Ultrastructural studies showed some calcic concretions in mitochondria of hepatocytes and Purkinje cells, and lamellar structures in the cytoplasm of Purkinje cells, probably of ergastoplasmic origin. The activity of dopamine-beta-hydroxylase (DBH, or norepinephrine synthesising enzyme) and of phenylethanolamine - N-methyltransferase (PNMT, or epinephrine synthesising enzyme) was studied in 22 samples of brain stem. Activity was reduced in 3 samples, and increased in 4 : 6 of these 7 samples were from structures involved in cardiovascular and respiratory control. These results suggest the existence of a central vegetative neuropathy, which could explain the cardiovascular and respiratory disturbances sometimes reported in Menkes' disease ; but this neurochemical study gave no account of the sleep organization alterations of the patient.

Two cases of peripheral neuropathy beginning in childhood are reported. Both had features suggestive of HMSN with pes cavus and kyphoscoliosis. Familial history of HMSN type I was present in 9 members of the kinship in case 1. In case 2, a mild neuropathy without pes cavus was present in the father. Case 1 developed four relapses of ascending sensory-motor deficit with conduction blocks suggestive of a superimposed chronic inflammatory polyneuropathy (CIP) which improved under prednisone. In case 2, the course was progressive with a severe proximal and distal motor weakness and sensitive disturbances. CSF protein concentration was high. Nerve biopsy showed rare onion bulbs and intense demyelination. These results joint to the unspecificity of the father's neuropathy are consistent with a probable childhood. CIP which improved under prednisone. These two cases indicated that in some patients with unusual symptoms for HMSN, prednisone should be considered and that the physiopathology of these neuropathies is probably heterogeneous.

A 60 year-old man complained of numbness and pain in the right lower limb, suggesting lesions of the fifth lumbar and first sacral roots. Sixteen months later, CT showed a tumor of 3.5 cm at the emergence of the first right sacral root. Microscopic examination disclosed an infiltration of the fibers of the nerve by numerous masses of hyaline eosinophilic material which stained with Congo red and produced green birefringence under polarized light. The persistence of congophilic properties of the amyloid deposits after permanganate pretreatment suggested an immunoglobulin origin (AL). A research of amyloid deposit in others viscera: heart, kidneys, digestive tract, was negative. We believe that this is the first reported case of amyloid pseudo-tumor involving a peripheral nerve.

Dopamine beta hydroxylase (DBH), The noradrenaline-synthesizing enzyme, and phenyl-ethanolamine-N-methyltransferase (PNMT), the adrenaline-synthesizing enzyme, were assayed in 18 areas of brain stem in eight cases of parkinsonian syndromes and of four age- and postmortem delay-matched controls. Dissection was performed by the "punch" technique and enzyme activities assayed by radiometric methods. No significant change was found for PNMT activity. DBH activity was significantly increased in the A2-C2 area of the medulla oblongata (including the nucleus tractus solitarius) in the cases of Parkinson's disease. The A2-C2 area is known to be implicated in the control of blood pressure in rats. These findings are discussed in relation to orthostatic hypotension and the influence of L-dopa therapy.