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M Poisson

Publications and source records attributed to M Poisson.

At least 109 records · Page 6Linked to original sources
PubMed1985

[Early manifestations of neuromeningeal syphilis. Review of the literature apropos of 3 severe forms].

We report 3 cases of severe syphilitic neuro-meningitis during the secondary stage: acute transverse dorsal myelitis with permanent paraplegia in a 17 year old teenager (case no. 1), uveo-meningitis with intracranial hypertension and diminished vision in a 52 year old woman (case no. 2), lower medulla lesion in a 46 year old man (case no. 3). The diagnosis was based upon highly positive serological tests for syphilis, associated with a compatible clinical context and meningitis in CSF specimens. Treatment was successful in cases nos. 2 and 3, unsuccessful in case no. 1 due to the irreversible character of the medullar lesions. Based on these 3 cases, the following points are discussed: the relatively atypical clinical character in the current context, the difficulties of the diagnosis, and the treatment regimens recommended for neurological syphilis. Despite the rarity of such cases, their extreme severity early in the secondary stage strongly implies the necessity for prevention by detecting and treating early syphilis. Attention is drawn upon the importance of doing serological tests for syphilis when presented with any atypical neurological situation.

Adolescent↗
PubMed1985

Comparison of the concentration-effect relationship of a local antiinflammatory agent and oral acetylsalicylic acid: the value of local application.

Using a pharmacological model, the comparison between acetylsalicylic acid (ASA), administered orally, and a solution combining two salicylate derivatives (ethyl 5-methoxy-salicylate and 3-phenyl-propyl-salicylate), applied locally, demonstrated the value of the local application. Indeed, the pharmacological activity was highly significant and directly related to the tissue concentration of salicyl ions, which was higher after local application of the solution than after oral administration of ASA. The local solution also resulted in a lower plasma concentration of salicylate ions, allowing high plasma salicylate concentrations to be avoided.

Administration, Topical↗
PubMed1984

Cytosolic and nuclear sex steroid receptors in meningioma.

To determine the nature of the hormone dependency of meningioma, particularly whether progestin receptor (PR) and tumor growth are estrogen-dependent, we measured the cytosol estrogen receptor (ER) and PR separately by an exchange assay with [3H]R 2858 (for ER) and [3H]RU 27987 (for PR) in 21 meningiomas. We correlated these receptors with age, plasma estradiol and progesterone concentrations, histological subtypes, clinical data such as uterine fibromas, and finally preoperative glucocorticoid therapy. ER was detected at low levels in the cytosol and in the nucleus of a few tumors whereas PR was found in 20 of 21 cases at moderate to high levels, usually with higher concentrations in the cytosol than in the nucleus. No clear relation could be drawn between either cytosol or nuclear ER and PR levels and estradiol and progesterone plasma concentrations, or with the other parameters. On the contrary, a clear correlation could be drawn between cytosolic PR and androgen receptor (AR) concentrations (measured with [3H]R 1881 in the presence of triamcinolone acetonide), leading to several hypotheses of hormonal regulation in meningioma.

Adult↗
PubMed1984

Biochemical characterization of 17 beta-hydroxysteroid dehydrogenase in human meningioma.

17 beta-Hydroxysteroid dehydrogenase (E2-DH) activity was characterized on a semipurified microsomal preparation of human meningioma tissue (mean Km of 2 microM and Vmax of 500 pmol/mg protein/10 min) and then assayed in 49 meningioma specimens with high progesterone receptor and low estrogen receptor levels. Of these 49 tumors, 36% contained an E2-DH activity greater than 1,000 pmol/mg protein/10 min and similar to that of uterine myometrium. In this limited series of tumors, no correlation between E2-DH activity and progesterone receptor levels was noted.

17-Hydroxysteroid Dehydrogenases↗
PubMed1984

Cerebral edema associated with meningiomas: possible role of a secretory-excretory phenomenon.

A retrospective study of cerebral edema in 40 patients with intracranial meningiomas seems to demonstrate that the extent of edema is not related to anatomical factors such as location. Histological type is more significant; cerebral edema is usually observed with meningothelial forms. Furthermore, the study of tumor cells by electron microscopic methods indicates that secretory-excretory activity is closely associated with with the production of peritumoral edema. The ultrastructural aspects of this secreted material are described, but further biochemical studies are necessary to determine its exact nature. The possible role of tumoral steroid receptors in the secretory-excretory phenomenon is discussed.

Brain Edema↗
PubMed1984

A new type of anticonvulsant, stiripentol. Pharmacological profile and neurochemical study.

4,4-Dimethyl-1-[3,4-(methylenedioxy)-phenyl]-1-penten-3-ol (stiripentol), selected from a series of alpha-ethylene alcohols, demonstrated anticonvulsant activity in studies in the rat and rabbit in which convulsions were induced electrically and chemically using pentetrazol, bicuculline and strychnine. Neurochemical studies showed that stiripentol in vitro did not act as a GABA receptor agonist, instead it inhibited the synaptosomal uptake of 3H-labelled GABA. Stiripentol has been shown elsewhere to inhibit GABA transaminase. These findings suggest that the anticonvulsant activity of stiripentol involves two aspects of the GABAergic mechanism in which the metabolic transamination and synaptosomal uptake of this neurotransmitter are inhibited.

Animals↗
PubMed1984

[Steroid receptors in the central nervous system. Implications in neurology].

This review deals with steroid hormones and receptors in relation to the physiology and the pathology of the central nervous system (CNS) and meninges. In recent years experiments performed in animals showed that: 1) endogenous steroid hormones cross the blood brain barrier: 2) radiolabelled steroid hormones bind in specific areas of the CNS; 3) all five classes of steroid receptors, i.e. oestrogen, progesterone, androgen, glucocorticoid and mineralocorticoid receptors (OR, PR, AR, GR, MR), are present in brain tissues, especially in the hypothalamus and the limbic system; 4) the interaction of steroid hormones and specific receptors induces the synthesis of proteins in the CNS; 5) finally, in situ metabolism of steroid hormones has been evidenced by the presence of specific enzymes. A few studies in human brain tissues have shown the presence of GR and OR as well as enzymes involved in the metabolism of sex steroid hormones. In neurology, some epidemiological and clinical data suggest the implication of steroid hormones and receptors in human CNS: 1) the influence of oestrogens in tardive dyskinesia; 2) the relevance of hormonal changes in benign intracranial hypertension; 3) the usefulness of glucocorticoid therapy in many patients with intracranial tumors and/or edema. Due to feasibility, most researches have concerned tumors: meningioma, neurinoma and glioma. Firstly, a reappraisal of biochemical and histochemical technics used to detect and characterize the receptors in tumors is presented. Then results from the recent literature are reviewed. In meningioma, PR was found in 89 p. 100 (152/177) of the cases, usually at moderate to high levels (up to 33 000 fmol/gT). In addition, PR has been fully characterized from a biochemical point of view. Furthermore, it has been hypothesized that PR may be a marker of leptomeningeal cells since it was detected at high levels in well differentiated tumors provided they had no or few psammoma. This was further supported by the discovery of PR in normal leptomeninges in human adults. OR was detected in 48 p. 100 (87/177) of the meningioma, at low levels. This is in contrast with PR but the percentage of cases with OR raises to 70 p. 100 (42/60) if one considers only tumors assayed for both cytosolic and nuclear receptors. Therefore it has been suggested that OR had translocated into the nucleus, at least in some cases, and subsequently the hypothesis of functional OR in meningioma was raised. AR was also detected in meningioma. Furthermore AR levels were found to correlate well with PR levels.(ABSTRACT TRUNCATED AT 400 WORDS)

Adrenal Cortex Hormones↗
PubMed1984

[Progesterone receptors in normal human leptomeninges in adults].

Cytosolic and/or nuclear 3H-R 5020 binding sites were detected in 6/6 samples of normal leptomeninges obtained at the time of operation in human adults. The levels of binding sites were higher in leptomeninges samples (range of values: 140-1780 fmol/gT) than in the corresponding intracranial tumors (one meningioma, two neurinomas, one metastasis) in 3 out of the 4 cases that were simultaneously studied. The 3H-R 5020 binding systems were characterized in 2 groups, A and B, of pooled samples representing respectively 4 and 17 samples of normal leptomeninges. The study of A (cytosolic and nuclear binding sites) and B (cytosolic binding sites) groups showed that binding systems had a limited capacity and a high affinity (Kd were respectively 2 X 10(-9) and 5.3 10(-10) M) as previously noted for the progestin receptor in human meningioma. Biochemical data and ultrastructural pictures obtained in the present study as well as in previous works, allow to consider the presence of the progestin receptor in normal leptomeninges.

Adult↗
PubMed1983

Two cases of acute leukemia following treatment of malignant glioma.

Two female patients, 42 and 30 years old, respectively, died of acute nonlymphocytic leukemia 43 and 38 months, respectively, after a subsequent treatment: chemotherapy for one and irradiation and chemotherapy for the other, following excision of a malignant glioma. At the time of death, both seemed to be in complete remission of their brain tumor. Both had been treated with procarbazine and nitrosoureas. The latter were responsible for severe myelosuppressive episodes and seem to have played an essential role in the induction of the leukemia. In one case, a myelodysplasia was observed before the onset of the AL and the diagnosis of refractory anemia with excess of blasts seemed warranted. Secondary acute leukemias are rare in the evolution of malignant gliomas and the usefulness of subsequent radiochemotherapy cannot be questioned at the present time. The risks involved in this therapy are minor when compared to the short-term fatal prognosis of this type of tumor.

Acute Disease↗
PubMed1983

[Kinetics of multicellular spheroids developed from a human glioblastoma, and effect of 1,3-bis (2-chloroethyl)-1-nitrosourea].

Multicellular spheroids (MCS) were yielded in vitro by early stages of human glioblastoma cell cultures. The spheroids were grown in suspension in the culture medium in agarose-coated (0.65%) dishes. The volume doubling time during the exponential growth phase was longer (13 days) than the population doubling time of monolayer cultures (2-3 days). Pathological examination of MCS showed a thin proliferative outer layer and areas of necrosis in the center. In two experiments BCNU caused a growth delay of MCS which was dose-related. The cells were sensitive to BCNU in monolayer cultures (CFE's assay), whereas the tumor was resistant in vivo. The usefulness and pitfalls of studies using MCS cultured from early passages of human malignant gliomas are discussed.

Brain Neoplasms↗
PubMed1983

Status spongiosus in the course of treatment of malignant gliomas.

Two cases of fatal encephalopathy which appeared in the course of treatment of malignant gliomas are described. CT scan showed diffuse, low density, non-enhanced lesions of the white matter. Pathological findings showed that the CT scan aspects corresponded to status spongiosus without demyelination. We were unable to find similar reports in the literature.

Brain↗
PubMed1983

Steroid hormone receptors in human meningiomas, gliomas and brain metastases.

Progestin, estrogen, androgen, glucocorticoid as well as mineralocorticoid receptors (PR, ER, AR, GR and MR, respectively) were all evaluated with specific synthetic radioligands (biochemical assays) in 25 meningiomas, 9 gliomas and 4 brain metastases. In meningiomas the main steroid hormone receptors appeared to be the progestin receptor, present in 24/25 cases (mean level: 7 105 fmol/gT) and the androgen receptor, present in 23/25 cases (mean level: 2 265 fmol/gT). Progestin receptor levels were found to be significantly lower in meningiomas of the fibroblastic subtype whereas none of the steroid hormone receptors were detected in the anaplastic case. On the other hand, glucocorticoid receptor levels were related to the preoperative glucocorticoid therapy. In gliomas only estrogen receptors (2/9 cases) and especially androgen receptors (8/9 cases) were noticeable: the latter seemed to be related to the histological types and to the sex of patients. No receptors were found in any of the four studied metastases, including one from breast cancer. The biochemical characterization of the receptors as well as their relevance to tumor biology and to the physiology of the normal tissues where tumors arise, were discussed, and biochemical data were compared with those previously reported.

Adult↗
PubMed1983

[Hypothalamic form of Whipple's disease. Favorable effect of rifampicin].

An unusual case of Whipple's disease is reported. The diagnosis was difficult as the characteristic digestive sign and symptoms (malabsorption, diarrhea, mucosal infiltration by PAS-positive macrophages) were absent. After a ten-year history of seronegative arthritis, myocardiopathy, with aortic insufficiency, basilar pulmonary infiltrates, enlarged lymph nodes, the patient, a 56 years old man, was referred to us for a severe vegetative and neurological dysfunction: stupor, dysarthria, akinesia, hypertonia, hypothermia and abnormal thirst. A CT-scan showed a low-density area of the right hypothalamus, and PAS-positive macrophages were found in a lymph node, in the CSF and in a cerebral biopsy. The patient then received a classical antibiotic treatment, yet the neurologic dysfunction remained severe. Finally, a trial with rifampicin brought a striking improvement of the patient's condition, which has now lasted for three years.

Humans↗
PubMed1983

[Acquired cerebral toxoplasmosis in adults. Clinical and neuropathologic study].

Two cases of acquired cerebral toxoplasmosis in adults are reported. In the first case no subjacent disease was found, and the neurological signs were of a meningo-encephalitic type with disorders of consciousness and a C.S.F. cellular reaction. A second case was observed in the course of the treatment of Waldenström disease by chloraminophene. The neurological signs were bifocal, and the C.S.F. showed a moderate increase of protein. In both cases C.T. scan showed contrast enhanced and hypodense areas. In the first case the enhancement was heterogenous and the hypodense area occupied the whole right hemisphere. The second case showed two ring enhancements in the left frontal and the right occipital regions. A cerebral biopsy was performed in both cases but no parasite was found. The diagnosis was presumed to be malignant lymphoma or encephalitis in the first case, glioblastoma in the second. No specific treatment was administered and the patients died within a few weeks. The complete pathological study by light and electron microscopy showed free and cystic forms of Toxoplasma Gondii. The results of the neuropathological examination and the thorough study of the biopsy specimens were compared to the pathological findings in the literature. The particular character of the necrosis and the inflammatory encephalitic reaction in the absence of the parasite may suggest the diagnosis when the clinical, biological and radiological data are compared.

Aged↗