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J P Muller

Publications and source records attributed to J P Muller.

At least 19 recordsLinked to original sources
PubMed1991

Molecular cloning and expression of ferritin mRNA in heavy metal-poisoned Xenopus laevis cells.

In a search for genes transcriptionally regulated by metal ions, we have isolated a Xenopus laevis ferritin cDNA clone, XL2-17, from cadmium-poisoned XL2 cells. The large size of the corresponding ferritin mRNA (1.4 kb) is due to the presence of a 629-nucleotide 5'-untranslated region. The Xenopus ferritin sequence is highly isologous with other vertebrate ferritins. In particular, there is a complete sequence identity for the iron-responsive element (IRE) located in the 5'-untranslated region in both XL2-17 and Rana catesbeiana ferritin mRNAs. The position of this IRE is unusual since it is located 489 nucleotides from the 5' end of the ferritin mRNA. Our analysis of phylogenetic relationships among ferritins indicates that all amphibian ferritins thus far sequenced would be more closely related to the mammalian H-type ferritin than to the L-type. The level of ferritin mRNA in XL2 cells rises 10- to 15-fold following exposure of cells to cadmium or copper. This increase is due to both transcriptional and translational regulation. A 10-fold increase was also found at the protein level. These results suggest that ferritin may be a primary detoxification response to heavy metals in Xenopus cells.

Amino Acid Sequence↗
PubMed1991

Plasma vitamin E, total lipids and myeloperoxidase levels during spinal surgery. A comparison between two anesthetic agents: propofol and isoflurane.

Plasma levels of vitamin E (Vit. E), total lipids (TL), Vit. E to TL ratio and myeloperoxidase (MPO) were studied in 20 patients undergoing lumbar spinal surgery and randomly allocated to two anesthetic groups: propofol (bolus dose + continuous infusion and thiopental/isoflurane. Peripheral blood samples were withdrawn prior to induction, each hour during anesthesia and 1 h after the end of surgery. Mean Vit. E and TL levels as well as mean Vit. E to TL ratios remained in the normal range over the entire period of study whatever the anesthetic regimen. MPO levels rose significantly in the post-operative period only, but without statistical difference between the two groups. Therefore, anesthesia with propofol or thiopental/isoflurane modifies neither total lipid concentrations nor plasma Vit. E, which is a potent endogenous inhibitor of lipid peroxidation bound to lipoproteins. The rise of plasma MPO suggests a moderate post-operative neutrophil activation which is not influenced by anesthetic techniques.

Adult↗
PubMed1990

[Hemiballismus. Hemichorea. Striatal infarction].

Lesions of other structures than corpus Luysii, may rarely cause hemiballism. A case is reported of hemiballism due to infarction of the territory supplied by the lenticulo-striatal arteries. CT and MR imaging showed lesions of the caudate nucleus and putamen. This suggested that the cause of the hemiballism was the suppression of the regulatory activity of the caudate nucleus on the pallidum.

Aged↗
PubMed1990

[Internal carotid occlusion and essential thrombocythemia. 2 cases].

We report 2 cases of occlusion of the internal carotid artery in young, non-atherosclerotic patients with essential thrombocythemia (ET). This complication of ET seems to be rare, but is probably underdiagnosed since transient ischemia, which is frequent in ET patients, is seldom explored by angiography. The excess of thrombocytes and the thrombopathy may account for the microvascular complications, but in the absence of any other contributory factor, occlusions of large arteries, such as the ICA, is more difficult to explain.

Adult↗
PubMed1990

[Obsessive-compulsive behavior and progressive supranuclear palsy].

A case of progressive supranuclear palsy characterized by a loss of self-activation and a compulsive behaviour of the obsessive type is reported. The pathological examination was remarkable for the intensity of pallidal lesions and their diffusion to both the external and internal segments. While the loss of self-activation seemed to result from a damaged cortico-subcortical circuit forming a limbic loop, the compulsive behaviour of the obsessive type may have resulted from the interruption of a frontal-caudal-pallidal-luysian circuit.

Globus Pallidus↗
PubMed1989

Transcription of dispersed repeated sequences during Pleurodeles waltl oogenesis.

Several repeated DNA sequences were isolated from a partial genomic DNA library of the newt Pleurodeles waltl. These repeated DNA elements are dispersed over the 12 P. waltl bivalents, and some of them are transcribed in the oocyte. We describe the localization of label following in situ hybridization to nascent RNA attached to the lateral loops of lampbrush chromosomes. Variations in the number and the location of labelled loops were constantly found for several of the probes. The results are discussed in view of the "cotranscription model" of RNA synthesis on lampbrush chromosomes. We speculate on the possible origins of variation in transcription on lampbrush loops.

Animals↗
PubMed1989

[Mitochondrial myopathy. Encephalopathy with lactic acidosis and cerebral infarction].

A 21 year-old man presented with a history of sudden onset of aphasia and headache. CT showed a left parietal hypodensity and pallidal calcifications. The ECG showed a Wolff-Parkinson-White's syndrome. The patient then developed successively focal epileptic seizures, temper disorders, a cardiomyopathy, a pepper and salt retinopathy with hemeralopia, a left hemiplegia, deafness, and fever of unexplained origin. Left carotid angiography showed thin, irregular or occluded branches of the middle and anterior cerebral arteries. Blood muscle enzymes, lactate and pyruvate, were elevated with acidosis. Muscle biopsy revealed a mitochondrial myopathy and blood chemistry showed a severe deficiency of respiratory chain enzymes. Death occurred after 28 months. This case showed the diagnostic features of Melas, with some elements of the Kearns-Sayre syndrome. To our knowledge, this is the first case were serial angiographies allowed demonstration of arterial changes capable of explaining cerebral infarctions.

Acidosis, Lactic↗
PubMed1989

[Recurrent meningitis, hydrocephalus and tegmen tympani dehiscence].

Cerebrospinal fluid (CSF) otorrhea is the usual presenting symptom of spontaneous tegmen tympani defects. A case associated with recurrent meningitis and CSF rhinorrhea without otorrhea is described. The coexistence of an hydrocephalus had led initially to ventriculoperitoneal shunting, which did not prevent meningitis recurrence. Previously reported in cases of anterior fossa and sella defects, an aqueduct stenosis was here associated with the tegmen tympani defect.

Adult↗
PubMed1989

[Bilateral paramedian thalamic infarction: a case with MRI and gamma-emission tomography].

A 41-year-old woman presented with a history of sudden onset of a dementia with frontal signs and antero-retrograde amnesia. CT showed a bilateral paramedian thalamic infarct which was confirmed by MRI. The study of regional cerebral blood flow showed a decrease in both frontal regions. Results of imaging suggested lesions of the ventro-oral, latero-polar and intralaminar nuclei as well as of the mammillo-thalamic tract. The dorso-median nucleus appeared to be relatively spared.

Adult↗
PubMed1987

[Recurrent coma, papular mucinosis and benign dysglobulinemia].

A woman presented with a history of three regressive comas of undetectable etiology between the age of 52 and 57 years. An IgG lambda benign monoclonal dysglobulinemia was combined with a papular mucinosis (myxedematous lichen or the generalized form of Arndt-Gotton's scleromyxedema). In the 6 analogous cases documented in the literature the onset of coma occurred generally several weeks after an aggravation of the cutaneous lesions. The coma was preceded by an influenza-like syndrome followed by asthenia, malaise with vertigo and frequently epileptic seizures. During recovery, hallucinations and transient hepatic disorders were noted. Pruritus with pronounced hypereosinophilia preceded desquamation and regression of dermatologic lesions. These comas can lead to a fatal outcome (2 of 7 cases) or regress in 2 to 20 days usually without sequelae. The disease is probably of immunologic origin. The paraprotein or a serum factor could exert a direct toxic effect on brain. As in neurologic manifestations of malignant dysglobulinemia, explained initially by a "toxic encephalosis, clinical, angiography, biologic and immunologic data exist in favor of blood hyperviscosity. This hyperviscosity could result from polymer formation through intermediates immunoglobulins and other protein chains, or again from alteration of deformability of red cells by binding of paraprotein. Hyperviscosity syndromes are frequent in system diseases that are often associated with papular mucinosis. Whatever the exact mechanism of these "comas due to papular mucinosis", a logical choice is their treatment by immunosuppressants and plasmapheresis: in the case reported, the use of plasmapheresis as soon as premonitory signs had appeared probably prevented a fourth coma.

Alopecia↗