Biomedical subjects

M Parent

Publications and source records attributed to M Parent.

At least 19 recordsLinked to original sources

PubMed1992

Myasthenia gravis and steroid-induced myopathy of the respiratory muscles.

OBJECTIVE: We report a case of corticosteroid-induced myopathy with involvement of respiratory muscles observed in a myasthenic patient. PATIENT: A 37-years-old woman, under corticosteroid treatment for two years for typical myasthenia gravis was admitted to ICU for acute myasthenic respiratory failure. Weaning from mechanical ventilation remained impossible despite 4 plasma exchanges and azathioprine. The patient exhibited a progressive 12 kg weight loss with muscular weakness and atrophy. MEASUREMENTS AND RESULTS: Peripheral and diaphragmatic electromyography as well as histological study were consistent with a steroid-induced myopathy. Discontinuation of corticosteroid treatment was followed by a rapid weight gain with general improvement and allowed weaning from mechanical ventilation with a complete recovery. CONCLUSION: This case provides evidence that corticosteroid-induced myopathy may be observed in myasthenia gravis and may involve the respiratory muscles as well as the peripheral musculature.

Adrenal Cortex Hormones↗

PubMed1992

Fluid intake patterns in schizophrenia and normal controls.

1. Patterns of fluid intake and urine output was examined in schizophrenia and normal controls. 2. Fluid intake and urine output were significantly higher in schizophrenic patients. 3. Bouts of drinking correlated significantly with fluid intake but did not differ significantly between schizophrenic patients and normal controls. 4. Schizophrenic patients drink more per bout compared to normal controls.

Adult↗

PubMed1992

Central neurocytomas. Critical evaluation of a small-cell neuronal tumor.

We report herein the clinical and pathological features of 20 patients with central neurocytomas. Investigations for various differentiation antigens and cell type-specific markers were performed by immunohistochemistry using paraffin-embedded tissue. In addition, the expression of L1 adhesion molecule and of the various N.CAM (neural cell adhesion molecule) isoforms were investigated by immunoblotting studies in two frozen specimens. Central neurocytomas are clinically characterized by their intraventricular localization, occurrence in young adults, and good prognosis. It rarely occurs in patients over 50, but such cases have a poor prognosis. Total surgical excision is the best treatment. Radiotherapy is appropriate if surgery is incomplete or contraindicated. Histologically, central neurocytomas display the following features: an oligo-like pattern, usually associated with large fibrillary rosettes or perivascular arrangement, and a rich endocrine-type vasculature. Central neurocytomas have a remarkably homogeneous antigenic profile. GFAP expression is only found in scattered reactive astrocytes, S100 protein in reactive astrocytes and rare tumor cells. Among the pan-neuroendocrine markers, central neurocytomas always express neuron-specific enolase; they frequently express synaptophysin but never chromogranin A. Synaptophysin is the most reliable immunohistological marker for central neurocytomas; however, immunoreactivity could be lost with long formalin fixation. In these cases, electron microscopy is used to support the neuronal nature of the tumor cells. The expression of L1 adhesion molecule and the isoform 180 of N.CAM, indicates that central neurocytomas are formed by cells committed to neuronal phenotype. Nevertheless, advanced neuronal differentiation may be absent, as suggested by the persistence of embryonic N.CAM, the nonexpression of neurofilament proteins, and the absence of mature synapses in numerous cases. Central neurocytomas and neuroblastomas share some biochemical properties, but their respective clinicopathological features and biological behavior are dramatically different.

Adolescent↗

PubMed1992

[Primary malignant teratoma of the thyroid. Two cases involving immunohistochemical and ultrastructural studies].

Two cases of primary malignant teratoma of the thyroid are reported. The first case, which occurred in a 21-year-old female, was mostly composed of tumoral neural tissue and foci of foetal cartilage. The patient died with lung metastases within 5 months after the first symptoms. The second case, which occurred is a 8-year-old infant female, had epithelial and mesenchymal components without neural tissue. This case had a better prognosis with survival of four years after initial diagnosis. The different tumoral components were identified by a thorough histopathological examination of the thyroidectomy with immunological and ultrastructural studies. As for other teratomas, presence of immature neural tissue bore a poor prognosis. The clinical, histopathological features and the histogenesis of this rare tumour are described and literature is reviewed.

Adult↗

PubMed1992

[Multiple cerebral hemorrhage and amyloid angiopathy of the white matter in a case of Alzheimer's disease].

Amyloid angiopathy is a common pathological finding in Alzheimer's disease. It usually involves leptomeningeal and cortical vessels but spares the white matter. It may cause lobar cerebral hemorrhages at a late stage of the disease. We report a case of Alzheimer's disease at an early stage with diffuse lesions of amyloid angiopathy including some within the white matter, apparently responsible for 2 deep and 1 superficial cerebral hemorrhages.

Alzheimer Disease↗

PubMed1991

The stereotactic approach to brain stem lesions: a follow-up of 29 cases.

Stereotactic biopsy is the safest and most reliable method for the histological diagnosis of intraaxial brain stem lesions. The definitive pathological diagnosis permits the selection of adequate therapy. No operative and/or adjuvant therapy must be proposed without a previous histological diagnosis. This approach avoids the complication of inappropriate therapy and provides valuable prognostic information.

Adolescent↗

PubMed1991

On the tumorigenicity of mitochondrial DNA-depleted avian cells.

We have examined the tumorigenic potential of mitochondrial DNA-depleted (mtDNA-) cells derived from the tumorigenic chicken cell line DU24. The mtDNA- cells were unable to proliferate in the wing web of day-old chicks. Cytoplasmic hybrids resulting from crosses between the mtDNA- whole cells and cytoplasts from enucleated parental cells (mtDNA+) recover both mtDNA and tumorigenicity. These results are in accordance with those obtained in prior experiments where mtDNA was shown to modulate the anchorage-independent phenotype of transformed avian cells.

Animals↗

PubMed1991

Could Wallerian degeneration contribute to "leuko-araiosis" in subjects free of any vascular disorder?

To determine the possible role of Wallerian degeneration secondary to the grey matter neuronal loss in the pathogenesis of "leuko-araiosis", computerised tomography (CT) of the brain was studied in 98 normotensive and non diabetic subjects free of cardiac diseases: 32 with Alzheimer's disease, 36 with Parkinson's disease, eight with progressive supranuclear palsy, and 22 controls. In Alzheimer's disease, leuko-araiosis scores were greater than in control subjects. Leuko-araiosis was more prominent in anterior periventricular areas in Parkinson's disease and progressive supranuclear palsy, and in posterior periventricular areas in Alzheimer's disease. In two patients with Alzheimer's disease and leuko-araiosis, necropsy revealed diffuse white matter pallor, mild fibrillary astrocytosis, and in one patient limited hyaline thickening of small white matter vessels, without any infarction or hypertensive change. Changes were more severe in white matter close to cortical areas with a great density of neurofibrillary tangles. Leuko-araiosis was more severe or more widespread in Alzheimer's disease than in Parkinson's disease, progressive supranuclear palsy and normal ageing. Differences in the location of leuko-araiosis between the four groups might be due to differences in the location of the grey matter disorder and Wallerian degeneration rather than amyloid in Alzheimer's disease, Parkinson's disease, progressive supranuclear palsy and normal ageing. Wallerian degeneration might be another cause of leuko-araiosis in neuro-degenerative disorders beside previously reported extra-cerebral predisposing factors and amyloid angiopathy.

Aged↗

PubMed1991

Monosporium apiospermum meningoencephalitis: a clinico-pathological case.

Twenty nine cases of central nervous system infection due to Monosporium apiospermum have been reported. Six of them occurred after an aspiration pneumonia following a near drowning. The case of a 53 year old man is reported: M apiospermum was isolated from cerebrospinal fluid, sputum, urine and from the mud of the ditch where the patient had fallen. Though the treatment used recommended doses of intravenous, intrathecal and intraventricular amphotericin B, it was ineffective and the patient died 97 days after the near drowning. Necropsy showed that the ventricular infectious process was more prominent distant from the antifungal ventricular source.

Brain↗

PubMed1991

Meta-analysis of quinolone-theophylline interactions.

Several fluoroquinolones currently under investigation or on the market potentially interact with theophylline. In this study, meta-analysis methodology was used to evaluate the significance of findings from quinolone-theophylline interaction studies. Two major databases were searched: Index Medicus (from 1986 to March 1990) and Current Content/Clinical Medicine (from 1985 to March 1990). A total of 32 studies were retrieved; 20 of these met the inclusion criteria. With a large effect size (ES) value of 2.26, enoxacin is the strongest inhibitor of theophylline metabolism of this family. The fail-safe N value was 135, indicating that 135 studies enrolling an average of 8 patients and showing no interaction (i.e., ES = 0) would be required to lower the ES to the threshold value of 0.1, which we considered a priori to render the results nonsignificant. Other fluoroquinolones showed a degree of interaction that can be considered significant: ciprofloxacin (ES = 0.50, fail-safe N = 26), norfloxacin (ES = 0.31, fail-safe N = 10). Ofloxacin (ES = 0.13, fail-safe N = 4), lomefloxacin (ES = 0.12, fail-safe N = 2), and fleroxacin (ES = 0.06, fail-safe N = 2) provided the weakest evidence of interaction based on effect size and power. Among the fluoroquinolones studied, ofloxacin, lomefloxacin, and fleroxacin, when available, should be the fluoroquinolones of choice when the patient also is receiving theophylline.

Ciprofloxacin↗

PubMed1991

[Thalamocapsular metastasis of muco-epidermoid adenocarcinoma of the parotid gland].

A 58 years woman with muco-epidermitis carcinoma of the left parotid gland treated by parotidectomy and external radiation developed seven years later a left hemianopsia and moria related to thalamo-capsulo-lenticular lesions. Three stereotactic biopsies were performed. Neuropathological examination confirmed a secondary lesion of carcinoma with the same histological features than primary lesion of the parotid. Due to the metastasis location treatment consisted in external radiotherapy guided by stereotactic coordinates.

Adenocarcinoma↗

PubMed1991

[Liposarcoma of the infratemporal fossa. Apropos of a case].

The authors report about one female patient with a liposarcoma of the right infratemporal fossa. Such tumors are rare, making up 10 to 12% of all soft-tissue sarcomas. Their occurrence in a cervical site is rare, unlike that in the inguinal region, the retroperitoneum or the lower limbs. Their diagnosis is mainly established by the histopathological study. Computed tomography and magnetic resonance imaging are particularly useful to choose the surgical approach. The technique chosen for this infratemporal tumor was a transmandibular cervical approach. Evolution was favorable, and the patient has currently had no reoccurrence after two years.

Adult↗

PubMed1991

[Papillary--cystic tumor of the pancreas. Apropos of 1 case with histological, immunohistochemistry and ultrastructural study].

The authors report the clinical and histological features of a case of papillary and cystic tumour of the pancreas in a 34 year old man. The solid and papillary tumour architecture associated with pseudocystic areas and a richly vascular stroma gave this tumour an original histological appearance. The study of the immunochemical and ultrastructural features of the tumour cells suggested an acinar differentiation.

Adult↗

PubMed1991

[Bilateral cavernous sinus syndrome: Burkitt's lymphoma].

Bilateral cavernous sinus syndrome is usually due to a vascular disease, such as thrombophlebitis or arteriovenous malformation. In a 29-year old woman this syndrome revealed a malignant non-Hodgkin's lymphoma of the Burkitt type. In this case, the physiopathological mechanism was metastatic extension to the dura mater of a systemic lymphoma. The contribution of MRI to the diagnosis is emphasized.

Adult↗

PubMed1991

Unusual recurrence of chronic myelogenous leukemia following bone marrow transplantation.

We report a patient who developed a bone and adjacent soft tissue malignancy 22 months after bone marrow transplantation (BMT) for Philadelphia chromosome positive chronic myelogenous leukemia (CML). Concomitant bone marrow was cytologically and cytogenetically normal. Cytogenetic study of tumoral tissue was unsuccessful but DNA analysis revealed BCR-AB1 rearrangement similar to that observed in hematopoietic cells prior to BMT. The present case demonstrates that molecular analysis is helpful in the diagnosis of unusual relapse of CML.

Adult↗

PubMed1990

Mitochondrial DNA modulation of the anchorage-independent phenotype of transformed avian cells.

The progressive loss of mitochondrial DNA in the presence of ethidium bromide in immortal avian cell lines correlates with a decrease in their potential for anchorage-independent growth in soft agar. In short-term treated cells, this effect is reversible and the recovery of cloning potential parallels the recovery of control levels of mitochondrial DNA. Long-term ethidium-bromide-treated cells are permanently respiration-deficient and display anchorage-dependent growth. Anchorage-independent revertants can be selected, suggesting that the lack of a respiratory chain per se might not be responsible for the inability of mitochondrial DNA-depleted cells to grow in soft agar. Cybrids formed from the fusion of mitochondrial DNA-depleted, anchorage-dependent cells to cytoplasts from parental cells are capable of growth in soft agar. The mitochondria-specific inhibitor, rhodamine 6G, prevents the recovery of the anchorage-independent phenotype in similar hybrids. These results suggest that mitochondrial DNA is required to maintain the transformed phenotype of avian cells.

Animals↗

PubMed1990

A double-blind comparative study of remoxipride and haloperidol in schizophrenic and schizophreniform disorders.

The antipsychotic effect of remoxipride was compared to that of haloperidol in a randomized double-blind study with parallel group design comprising 98 patients with schizophrenia or schizophreniform disorder according to DSM-III. After a 3-7 day placebo washout period, patients received either 150-600 mg of remoxipride or 5-20 mg of haloperidol daily for 6 weeks. No significant differences in efficacy were found between the two treatments. Treatment-emergent checklist symptoms such as hypokinesia, rigidity, and tremor occurred more frequently and were more severe during haloperidol than during remoxipride treatment despite a significantly higher concurrent use of anticholinergic drugs in the haloperidol group. Haloperidol-treated patients reported greater increases in sleep and salivation than remoxipride-treated patients. Shoulder shaking and tremor were reported as occurring more frequently in the haloperidol group according to the Simpson and Angus rating scale for extrapyramidal symptoms. In summary, the two drugs seemed to be equally efficacious, though the tolerability profile favoured remoxipride.

Adult↗

PubMed1990

Safety of fleroxacin coadministered with theophylline to young and elderly volunteers.

The influence of multiple doses of fleroxacin on the plasma clearance and the urinary excretion of theophylline was studied in 19 young and 18 elderly male volunteers. A theophylline dosage individualized to obtain a mean theophylline concentration in plasma of 10 +/- 3 micrograms/ml was administered for 1 week to each subject. At week 2, oral fleroxacin (400 mg once daily) was added. Theophylline concentrations in plasma were measured with TDx (Abbott Diagnostics, Mississauga, Ontario, Canada), and urinary excretion of theophylline and its three major metabolites was measured by high-performance liquid chromatography. Total theophylline clearance remained essentially unchanged throughout the study period (3.5 and 2.9 liters/h in the young and the elderly, respectively) both after a single fleroxacin dose and after multiple doses. Although significant changes occurred in the urinary excretion of unchanged theophylline and its metabolites after a single fleroxacin dose, no changes were observed after multiple doses. Side effects consisted mainly of gastrointestinal and sleep disturbances, more related to theophylline; photosensitivity was observed in six subjects and was attributed to fleroxacin. We conclude that fleroxacin may be administered concomitantly with theophylline in either young or elderly patients. Close monitoring of theophylline concentrations in serum should be performed, particularly in patients with chronic obstructive pulmonary disease, for whom data are currently lacking.

Adult↗