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Biomedical subjects

P Mailleux

Publications and source records attributed to P Mailleux.

At least 73 records · Page 4Linked to original sources
PubMed1992

Distribution of neuronal cannabinoid receptor in the adult rat brain: a comparative receptor binding radioautography and in situ hybridization histochemistry.

The neuronal distribution of cannabinoid receptor in the adult rat brain is reported, combining receptor binding radioautography using the synthetic psychoactive cannabinoid ligand CP55,940 with in situ hybridization histochemistry using oligonucleotide probes complementary to rat cannabinoid receptor cDNA. In the cerebral cortex, especially in the frontal and cingulate cortex, dense binding was found in layers I and VI together with slight mRNA levels in a majority of both pyramidal and non-pyramidal-shaped neurons and of high mRNA levels in a moderate number of non-pyramidal-shaped neurons especially in layers II-III and V-VI. In the hippocampal dentate gyrus, very dense staining was found in the molecular layer together with high mRNA levels in a moderate number of hilar neurons close to the granular layer. In Ammon's horn, especially in the CA3 sector, very dense binding was found in the dendritic layers together with slight mRNA levels in the majority of the pyramidal cells and high mRNA levels in a moderate number of interneurons. In the basal ganglia, binding was very dense in the lateral putamen, substantia nigra pars reticulata, globus pallidus and entopeduncular nucleus, moderate in the medial putamen and caudate; and slight in the accumbens, together with slight to moderate mRNA levels in the striatal medium-sized neurons. Together with slight binding, slight to moderate mRNA levels were found in the majority of the neurons in the subthalamic nucleus. No binding and mRNA were found in the substantia nigra pars compacta and ventral tegmental area. Slight to moderate binding was found together with slight to moderate mRNA levels in the majority of neurons in the anterior olfactory nucleus; septum, especially medial septum and diagonal band of Broca; amygdala, especially basolateral amygdala; lateral habenula; ventromedial hypothalamic nucleus; lateral interpeduncular nucleus; central gray, dorsal cochlear nucleus; parabrachial nucleus; dorsal pontine tegmentum; pontine nuclei; commissural part of the nucleus tractus solitarius; inferior olive and dorsal horn of the spinal cord. In the cerebellum, very dense binding was found in the molecular layer together with slight mRNA levels in the majority of the granule cells and moderate mRNA levels in the basket and stellate cells. In conclusion, this study provides, for the first time, indirect assessment of the neurons containing cannabinoid receptor in the entire adult rat brain and will serve as a basis for future direct morphological confirmation using receptor immunohistochemistry and for functional studies.

Animals↗
PubMed1992

Fatal familial insomnia: clinical and pathologic study of five new cases.

In 1986, we reported two anatomoclinical observations of a familial condition that we called "fatal familial insomnia" (FFI). We now present the pedigree as well as the clinical and neuropathologic findings in five new subjects. The pedigree includes 288 members from six generations. Men and women are affected in a pattern consistent with an autosomal dominant inheritance. The age of onset of the disease varies between 37 and 61 years; the course averages 13 months with a range of 7 to 25 months. Progressive insomnia (polygraphically proven in two cases); autonomic disturbances including hyperhidrosis, hyperthermia, tachycardia, and hypertension; and motor abnormalities including ataxia, myoclonus, and pyramidal dysfunction, were present in every case, but with variable severity and time of presentation. Sleep and autonomic disorders were the earliest signs in two subjects, motor abnormalities were dominant in one, and others had intermediate clinical patterns. Pathologically, all the cases had severe atrophy of the anterior ventral and mediodorsal thalamic nuclei. Other thalamic nuclei were less severely and inconsistently affected. In addition, most of the cases had gliosis of the cerebral cortex, a moderate degree of cerebellar atrophy with "torpedoes," and severe atrophy of the inferior olivary nuclei. One case also showed spongy degeneration of the cerebral cortex. We conclude that all the lesions were primary, and that FFI is a multisystem disease in which the different structures are primarily affected with different severity. The insomnia appears to correlate best with the major thalamic pathology. The possibility that FFI belongs to the group identified as prion diseases or diseases transmitted by unconventional agents is examined.

Adult↗
PubMed1992

[Lumbar arachnoid cysts: 2 unusual cases].

Two cases of arachnoid cyst in the lumbar region are described. One is intradural, acquired, and associated to severe arachnoiditis while the other is extradural in location and probably congenital. The interest of myelography, CT myelography, and MRI for the diagnosis is discussed.

Adult↗
PubMed1992

[Anorectal anaplastic cancer (neuroendocrine)].

An extensive case of undifferentiated neuroendocrine carcinoma with small cells of the anorectal region is reported. The carcinoma is related to pulmonary anaplasia and quite rare in the colonic and rectal region. Its aggressivity is considerable with a strong propensity for hematogenous and lymphatic metastases and with a disastrous prognosis: 0% survival over 1 year. The incidence, the characteristic features, the histogenesis, and the anatomical pathology of this rare neoplasm are mentioned. Furthermore, the case illustrates a radiological pattern typical for major lymphatic dissemination with an intra- and extraparietal component. The mechanism of dissemination is explained by the "lymphatic block" theory. The absolute necessity of obtaining an histology in radiologically unusual and/or extensive cases is mentioned.

Adult↗
PubMed1991

Inositol 1,4,5-trisphosphate 3-kinase distribution in the rat brain. High levels in the hippocampal CA1 pyramidal and cerebellar Purkinje cells suggest its involvement in some memory processes.

The distribution of inositol 1,4,5-trisphosphate (InsP3) 3-kinase was studied in the adult rat brain, using polyclonal antibodies raised against the purified 50,000-Da rat brain enzyme by immunohistochemistry and Western blot, in addition to enzymatic assay. Immunohistochemically, the enzyme was detected in neurons, where it was localized in the dendrites and at the periphery of the cell bodies. Using selective toxin lesions, the highest enzyme levels were found in the dendrites of hippocampal CA1 pyramidal cells and in neurons in the dorsal portion of the lateral septum, regions both involved in long-term potentiation; and in the dendrites of Purkinje cell subpopulations in the cerebellum, a region involved in long-term depression. High levels were found in neurons in the cortex; in the anterior olfactory nucleus; in the striatum (caudate, putamen, olfactory tubercle, Calleja islets and accumbens); in the central nucleus of the amygdala; in the hippocampal dentate gyrus and in the subiculum. The enzyme was not detected in other brain regions. By Western blot, a 50,000-Da immunoreactive band was present in the cortex, caudate-putamen and cerebellum. This band was most highly stained in the hippocampus. InsP3 3-kinase activity, stimulated by calcium/calmodulin, corresponded to 6172-2638 pmol of InsP4 produced/min/mg protein in the hippocampus followed by frontal and parietotemporal cortex and cerebellum. This activity was below 400 in the brainstem and spinal cord.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1991

Inositol 1,4,5-trisphosphate 3-kinase mRNA: high levels in the rat hippocampal CA1 pyramidal and dentate gyrus granule cells and in cerebellar Purkinje cells.

The distribution of inositol 1,4,5-trisphosphate (InsP3) 3-kinase mRNA in the rat brain is reported using oligonucleotides based on a cDNA clone sequence that encodes rat brain InsP3 3-kinase and the in situ hybridization technique. Moderate levels were found in CA2-4 pyramidal neurons, in the cortex, and in the striatum. The cerebellar granule cells, thalamus, hypothalamus, brainstem, spinal cord, and white matter tracts were almost negative. The levels of InsP3 3-kinase mRNA were highest in the hippocampal CA1 pyramidal neurons, granule cells of the dentate gyrus, and cerebellar Purkinje cells. These results contrast with the lower concentration of the InsP3 receptor already reported in the hippocampus versus the Purkinje cells and suggest a special role for inositol 1,3,4,5-tetrakisphosphate in Ammon's horn.

Animals↗
PubMed1990

Neurotensin reduces the affinity of dopamine D2 receptors in membranes from post mortem human caudate-putamen.

The effects of neurotensin in vitro were investigated on the binding characteristics of N-[3H]propylnorapomorphine [( 3H]NPA) binding sites in crude membrane preparations from post mortem human caudate-putamen, obtained within 10 h after death from 3 patients without reported neurological or psychiatric diseases. Neurotensin (0.1-30 nM) was found to increase the KD value of [3H]NPA binding sites with a maximal increase of about 50% (420 +/- 45 pM) at 3 nM of neurotensin, without significantly affecting the Bmax value (123 +/- 20 pmol/g protein). These results indicate the existence of an intramembrane regulation by neurotensin receptors of D2 receptors in the human caudate-putamen.

Aged↗
PubMed1990

Transient neurotensin high-affinity binding sites in the human inferior olive during development.

High-affinity binding sites for neurotensin 1-13 are found transiently in the human inferior olive during development. An in vitro membrane binding assay demonstrates, in the fetus, a specific binding to a single population of sites (Kd = 561 pM) which are levocabastine-insensitive and possess a Bmax value of 71 fmol/mg protein. No specific binding is present in the adult. Film radioautography shows, in fetuses of 15 weeks, a labelling in the whole inferior olive. At 25 weeks and at 33 weeks, the labelling is concentrated in the ventral lamella of the principal olive and in the caudal accessory olives. At birth and until 1 month of age, the labelling is still detected in the medial part of the ventral lamella of the principal olive. The labelling disappears after 3 months of age, is absent at 4 and 6 months and remains absent in the adults from 55 to 81 years of age. At the light microscopic level, the labelling is located mostly outside olivary neuronal cell bodies suggesting its presence on afferent nerve fibers. This ontogeny and localization of the binding sites in the inferior olive is quite different from that of the neurotensin 1-13 nerve terminals.

Aged↗
PubMed1990

Analysis of expression of cholecystokinin in dopamine cells in the ventral mesencephalon of several species and in humans with schizophrenia.

The ventral mesencephalons of hamster, guinea pig, cat, monkey, and several humans with and without the diagnosis of schizophrenia were analyzed with in situ hybridization and immunohistochemistry. Extensive codistribution of cholecystokinin mRNA and tyrosine hydroxylase [L-tyrosine, tetrahydropteridine: oxygen oxidoreductase (3-hydroxylating), EC 1.14.16.2] mRNA was observed in cats and monkeys as well as in all five human subjects with the diagnosis of schizophrenia and in two out of five control brains. Double labeling revealed coexistence of the two markers in cat, monkey, and human. No cholecystokinin mRNA or cholecystokinin peptide was detected in the substantia nigra/ventral tegmental area of the hamster or guinea pig, even after acute and chronic neuroleptic treatment.

Animals↗
PubMed1990

[Pelvic plexiform neurofibroma: typical aspects in CT].

Plexiform neurofibroma is a relatively uncommon but characteristic manifestation of neurofibromatosis. Two pelvic cases were found by CT in two young patients in whom it was the first fortuitous manifestation of the disease. The CT pattern, which seems to be in close relation with pathology, is described and illustrated. This pattern is so typical that there is no difficulty to establish the differential diagnosis. The question of sarcomatous transformation is more problematic by CT.

Adult↗
PubMed1990

[Endobronchial lipoma: a potential CT diagnosis].

Bronchial lipomas are rare and benign neoplasms. Computed tomography can provide a powerful adjunct to conventional modalities in determining the nature of an endobronchial lesion. The reflex vasoconstriction can also be nicely depicted.

Bronchial Neoplasms↗
PubMed1989

An improvement of Barter's method for assaying plasma cholesterol ester transfer activity: experimental and clinical applications.

The use of a discontinuous density gradient and of a vertical rotor to separate plasma lipoproteins are modifications of Barter's described method for assaying cholesteryl ester transfer activity (CETA) in plasma. The original feature of our approach is the fast preparation of the labeled substrate by a physiologic-like process, which renders the assay easy and suitable for measurement of this activity in both man and animals.

Adult↗
PubMed1988

Transient neurotensin in the human inferior olive during development.

A large number of transient neurotensin-immunoreactive nerve terminals are found in the human principal inferior olive of the medulla oblongata during the first year of age and almost completely disappear in the adult. Their neurotensin content is further characterized as neurotensin(1-13) using radioimmunoassay and gel filtration and reaches 582 pmol per gram wet weight at 6 months. Neurotensin nerve terminals are exclusively located in the principal olive and a dense bundle of neurotensin nerve fibers is also present in the central tegmental tract. Thus, these olivary neurotensin nerve terminals probably originate in mesencephalic neurons. In addition to its recognized role in neurotransmission or neuromodulation, neurotensin may thus also be implicated in the postnatal development of the human principal olive and indirectly in that of the neocerebellum.

Adult↗