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P Mailleux

Publications and source records attributed to P Mailleux.

At least 37 records · Page 2Linked to original sources
PubMed1995

[Prostatic leiomyoma].

Large leiomyomas of the prostate are rare tumors. The authors report the case of a 78-year-old patient with two large prostatic leiomyomas who presented with chronic obstructive urinary symptoms. The US and CT aspects are illustrated; the signs are not specific but rather suggest a benign process. The tumor, probably of embryologic origin, must be distinguished from neoplasms when presenting in association with the classical benign prostatic hypertrophy. The definite diagnosis is obtained histopathologically. Prognosis is good with no evidence of recurrent disease.

Aged↗
PubMed1994

Distribution of immediate early gene zif-268, c-fos, c-jun and jun-D mRNAs in the adult cat with special references to brain region related to vision.

The distribution of immediate early gene zif-268, c-fos, c-jun and jun-D mRNAs was investigated in the visual cortex, dorsal lateral geniculate nucleus and hippocampus of the adult cat brain with in situ hybridization. In area 17, zif-268, c-jun and jun-D were found predominantly in layers II-III and VI, while c-fos mRNA was abundant in layer VI. In area 18, the zif-268, c-fos and c-jun labelling pattern was identical to that of area 17, this was not true for jun-D. In area 19, only c-jun retained the lamination pattern of areas 17 and 18, while zif-268, c-fos and jun-D were homogeneously distributed. In the dorsal lateral geniculate nucleus, only c-fos and jun-D resulted in labelling. In the pyramidal layer of hippocampus, zif-268 was found in CA1-4, c-jun in CA1-3, and jun-D in CA2-4. In the dentate gyrus, c-jun was abundant, jun-D moderate and zif-268 faint. C-fos labelling was absent in the hippocampal formation.

Animals↗
PubMed1994

delta-9-Tetrahydrocannabinol regulates gene expression of the growth factor pleiotrophin in the forebrain.

delta-9-Tetrahydrocannabinol (THC) is a major psychoactive component of cannabis. We here studied, by quantitative in situ hybridization at the macroscopic level, the possible modulatory effects of acute THC (5 mg/kg/i.p.) on gene expression of the growth factor pleiotrophin (PTN) in the adult rat forebrain. We found, 30 min after a single injection of THC, a significant increase of PTN mRNA concentrations in the cingulate cortex (38%), fronto-parietal cortex (31%) and caudate-putamen (27%). In conclusion, this is the first report on THC regulation of growth factor gene expression in the brain.

Animals↗
PubMed1994

Cloning and expression of human brain type I inositol 1,4,5-trisphosphate 5-phosphatase. High levels of mRNA in cerebellar Purkinje cells.

In brain and many other tissues, Type I inositol 1,4,5-trisphosphate (InsP3) 5-phosphatase is the major isozyme hydrolysing the calcium-mobilizing second messenger InsP3. We recently reported the cloning and expression of dog thyroid InsP3 5-phosphatase. During the course of this cloning, screening of a human brain cDNA library allowed us to isolate a cDNA clone D1 with 91% sequence identity with the thyroid sequence. When clone D1 was expressed in Escherichia coli, the fusion protein had InsP3 5-phosphatase activity. M(r) estimates of the recombinant enzyme made by immunodetection, activity assay after SDS/PAGE or silver staining were consistent with the calculated molecular mass. In situ hybridization on human cerebellum sections localised the mRNA for this enzyme to the Purkinje cells.

Amino Acid Sequence↗
PubMed1994

Activation of multiple transcription factor genes by tetrahydrocannabinol in rat forebrain.

delta-9-Tetrahydrocannabinol (THC) is a major psychoactive component of cannabis. We have recently localized a receptor for THC in the forebrain and found in the caudate-putamen that its gene expression is modulated by glucocorticoids, dopamine and glutamate. Here, we report for the first time, using quantitative in situ hybridization, that acute THC (5 mg kg-1, i.p.) regulates the mRNA levels of multiple immediate early genes in the adult rat forebrain. Twenty minutes after a single THC injection, significant increases in concentration of the mRNAs for C-FOS, C-JUN and ZIF-268 were observed in the cingulate cortex (75, 45 and 37%) and for C-FOS and ZIF-268 in the fronto-parietal cortex (60 and 64%) and caudate-putamen (81 and 32%) while JUN-D mRNA levels were not changed. These transcription factor genes might mediate putative THC modulation of neurotransmitter gene expression.

Animals↗
PubMed1994

delta-9-Tetrahydrocannabinol regulates substance P and enkephalin mRNAs levels in the caudate-putamen.

We have recently localized delta-9-tetrahydrocannabinol (THC) receptor in the projecting neurons of the striatum which are known to express the neuropeptides substance P and enkephalin. We now report for the first time, by quantitative in situ hybridization, that a 3-week treatment with THC significantly increases in the adult rat caudate-putamen the messenger RNAs levels for substance P and enkephalin. These data indicate that THC may regulate gene expression of neuropeptides in the brain.

Animals↗
PubMed1994

ORL1, a novel member of the opioid receptor family. Cloning, functional expression and localization.

Selective PCR amplification of human and mouse genomic DNAs with oligonucleotides encoding highly conserved regions of the delta-opioid and somatostatin receptors generated a human DNA probe (hOP01, 761 bp) and its murine counterpart (mOP86, 447 bp). hOP01 was used to screen a cDNA library from human brainstem. A clone (named hORL1) was isolated, sequenced and found to encode a protein of 370 amino acids whose primary structure displays the seven putative membrane-spanning domains of a G protein-coupled membrane receptor. The hORL1 receptor is most closely related to opioid receptors not only on structural (sequence) but also on functional grounds: hORL1 is 49-50% identical to the murine mu-, delta- and kappa-opioid receptors and, in CHO-K1 cells stably transfected with a pRc/CMV:hORL1 construct, ORL1 mediates inhibition of adenylyl cyclase by etorphine, a 'universal' (nonselective) opiate agonist. Yet, hORL1 appears not to be a typical opioid receptor. Neither is it a somatostatin or sigma (N-allylnormetazocine) receptor. mRNAs hybridizing with synthetic oligonucleotides complementary to mOP86 are present in many regions of the mouse brain and spinal cord, particularly in limbic (amygdala, hippocampus, septum, habenula, ...) and hypothalamic structures. We conclude that the hORL1 receptor is a new member of the opioid receptor family with a potential role in modulating a number of brain functions, including instinctive behaviours and emotions.

Amino Acid Sequence↗
PubMed1994

Glutamatergic regulation of cannabinoid receptor gene expression in the caudate-putamen.

Glutamatergic regulation of delta-9-tetrahydrocannabinol (THC) receptor gene expression in the adult rat dorsal striatum following a 2 week unilateral cerebral decortication or pharmacological treatment with MK-801 was investigated by quantitative in situ hybridization. The caudate-putamen on the side of the cerebral decortication contains about 30% significantly lower mRNA levels than the control. In addition, we observed a 52% significant decrease in THC receptor mRNA levels in intact dorsal striatum after treatment with MK-801. Together these results suggest that in vivo, through the NMDA receptor subtype, glutamate up-regulates THC receptor gene expression in the rat caudate-putamen.

Animals↗
PubMed1994

Homolateral cerebrocortical increase of immediate early gene and neurotransmitter messenger RNAs after minimal cortical lesion: blockade by N-methyl-D-aspartate antagonist.

A small surgical lesion of the parietal cortex induces an increase in the expression of several messenger RNAs varying from 172 to 980% in the entire homolateral cerebral cortex, as detected by quantitative in situ hybridization histochemistry. The messenger RNAs encoding the immediate early genes of the leucine zipper family (c-fos, c-jun, jun-B), the Zinc finger family (zif268), the glucocorticoid receptor family (NGFI-B) and the interferon family (PC4) are increased within 2 h after the lesion and return to normal levels at 6 h. The messenger RNAs encoding cholecystokinin, neuropeptide Y, somatostatin and the synthetizing enzyme of the neurotransmitter GABA, glutamate decarboxylase, are elevated within one day and return to normal levels after six days. An intraperitoneal injection of the N-methyl-D-aspartate receptor antagonist dizocilpine maleate, 30 min before surgery, prevented either the induction of immediate early gene expression or the increase of neuropeptide and glutamate decarboxylase messenger RNA expression. This study demonstrates that a minimal cortical lesion induces extensive changes in gene expression and that the mechanism(s) leading to these changes involves the action of glutamate at the N-methyl-D-aspartate receptor. These modifications may be of importance in explaining diffuse changes not related to neuronal circuitry in several conditions.

Animals↗
PubMed1994

[Pulmonary edema secondary to the intravenous administration of iodized contrast. A clinical case with high-resolution tomodensitometry studies].

Contrast media related reactions are numerous and of variable gravity. We report a case of pulmonary edema related to the intravenous administration of contrast media. Cardiogenic and non cardiogenic pulmonary edema are pathophysiologic possibilities. High resolution CT findings associate patchy ground glass areas and smooth thickening of subpleural septa, both rapidly disappearing.

Aged↗
PubMed1994

[Lipoma of the filum terminale: a prospective tomodensitometry study].

A lipomatous aspect of the filum terminale is sometimes recognized in routine lumbosacral CT studies as a small (1 to 2 mm) tubular fatty hypodensity that lies posteriorly in the dural sac. To study the epidemiologic frequency and pathological significance, the authors prospectively reviewed the standard lumbosacral CT studies of a large series of 1033 adult patients suffering from mechanical problems. The lipomatous aspect was encountered in 39 of them (3.77%). The average size was about 1 mm and never exceeded 2 mm (92%) except for 3 cases. The commonest site was L4-L5 but the anomaly was more commonly seen at two levels. Despite the lack of histological proof, the authors consider the lesion benign and trite with two restrictions: the pediatric cases (not studied in their series) and the patients presenting a lipoma greater than 3 mm; for these two groups further investigations are recommended to exclude a tethered cord syndrome.

Adult↗
PubMed1994

[A cause of intestinal intussusception in an adult].

Inflammatory fibroid polyp is a very rare tumor involving the gastrointestinal tract and especially the stomach and small bowel. It presents either as a solitary pedunculated or sessile lesion arising from the submucosa. Despite its large size and sometimes very infiltrating growth, the polyp is benign and has a good prognosis. The aetiology remains unknown but it probably represents a reactive proliferation similar in many respects to the granuloma pyogenicum. We report an ileal case which presented itself as an acute intussusception. The very typical and complete sonographic and tomodensitometric findings of this intussusception are detailed. The polyp alone does not have noteworthy radiological characteristic signs and must be included in the large and essentially histological differential diagnostic of gastrointestinal tumors.

Adult↗
PubMed1993

Inositol 1,4,5-trisphosphate 3-kinase highest levels in the dendritic spines of cerebellar Purkinje cells and hippocampal CA1 pyramidal cells. A pre- and post-embedding immunoelectron microscopic study.

Inositol 1,4,5-trisphosphate 3-kinase (InsP3 3-kinase) plays a crucial role in calcium homeostasis by regulating InsP3 levels. We have reported the highest concentrations of InsP3 3-kinase in the dendrites of cerebellar Purkinje cells and hippocampal pyramidal cells of the CA1 sector of the Ammon's horn. We here investigate its subcellular localization by pre- and post-embedding immunoelectron microscopic study. In both populations of neurons, the major structure expressing a high level of InsP3 3-kinase is the dendritic spines.

Animals↗
PubMed1993

Glucocorticoid regulation of cannabinoid receptor messenger RNA levels in the rat caudate-putamen. An in situ hybridization study.

The influence of adrenalectomy on cannabinoid receptor gene expression in the adult rat dorsal striatum was investigated by in situ hybridization with specific oligonucleotide probes. The caudate-putamen of adrenalectomized rats contains approximately 50% significantly higher mRNA levels than the controls. This increase could be counteracted by dexamethasone treatment. Together, these results suggest glucocorticoid down-regulation of cannabinoid receptor gene expression in the striatum.

Adrenalectomy↗
PubMed1993

Ontogeny of gene expression of inositol 1,4,5-trisphosphate receptor in the rat brain: high mRNA levels in the cerebellar Purkinje cells.

The release of intracellular Ca, which is involved in many neuronal functions, is regulated by the second messenger inositol 1,4,5-trisphosphate (InsP3) interacting with specific receptor. The distribution of the mRNA coding for the recently cloned InsP3 receptor was studied in the developing rat brain using oligonucleotides derived from the rat cDNA sequence and in situ hybridization. The localizations of the mRNA in the postnatal brain were exactly superimposable to that previously reported in the adult [Mailleux et al., Neuroscience, 49 (1992)577-590]. Higher mRNA levels were consistently found in the adult neurons over their postnatal counterpart. Hybridization signal was first visible in the cerebellar Purkinje cells which express dramatically higher mRNA levels of the receptor than any other neurons in the brain. In conclusion, the levels of InsP3 receptor mRNA per neuron increased with synaptogenesis. This finding suggests the occurrence during this critical developmental period of a more complex regulation of Ca fluxes, perhaps requiring higher intraneuronal levels of InsP3 receptor.

Aging↗
PubMed1993

Neuronal localization in the rat brain of the messenger RNA encoding calcyphosine, a new calcium-binding protein.

The cDNA encoding calcyphosine, a new calcium-binding protein of the calmodulin superfamily which is regulated by cAMP, has been cloned in the dog thyroid (EMBO J., 8 (1989) 111-116). By in situ hybridization with synthetic oligonucleotides, we here demonstrate for the first time its neuronal localization in the rat brain. Hybridization signal was detected in all the olfactory areas; in pyramidal and non pyramidal-shaped neurons in the different layers of the cerebral cortex, especially the superficial ones; in the pyramidal cells of the different sectors of the Ammon's horn and in the granule cells of the dentate gyrus of the hippocampus; in the subiculum; in the medium-sized and large neurons of the different quadrants of the caudate-putamen and accumbens and in the cerebellar Purkinje cells. Hybridization was also observed to a lesser extent in the majority of the neurons in the basal areas of the forebrain, including septum, nucleus of the diagonal band and amygdala; in the globus pallidus, entopeduncular nucleus, substantia nigra pars reticulata and compacta, ventral tegmental area; in the subthalamic nucleus; in the thalamus; in the hypothalamus; in the brainstem and in the upper cervical spinal cord. In addition to its neuronal localization, calcyphosine mRNA was also found in ependymal cells. The non-detection of positive cells in the white matter was not in favor of prominent glial localization, although it does not exclude it.

Animals↗