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J M Norès

Publications and source records attributed to J M Norès.

18 recordsLinked to original sources

[Chemicals toxic to the olfactory system. Analysis and description].

AN IMPORTANT PROBLEM: Occupational exposure to chemical products can have toxic effects on the olfactory system. An important number of patients have experienced olfactory disorders subsequent to the development of the chemical industry and atmospheric pollution. EPIDEMIOLOGY DATA: Straightforward data are difficult to collect because several cofactors other than the toxic product are involved. Two lists of toxic products can be made. The first list includes products for which scientific data is available and the second products for which data is lacking. Olfactory tests also differ between authors and countries. TWO TYPES OF TOXICITY: Acute, accidental toxicity is evidenced by the lesions caused by inhalation of high-doses of strongly toxic agents. Chronic intoxication caused by lower concentrations of these inhaled agents does not produce a trigeminal reflex leading to a modified respiratory rate reducing the airborne aggression. APPROXIMATIONS: Clinical data describing the olfactory toxicity of certain industrial and chemical compounds are very significant but often cannot prove a cause and effect relationship. Data obtained with experimental models in rodents are difficult to extrapolate to humans.

Air Pollutants, Occupational↗

[Olfactory disorders due to medications: analysis and review of the literature].

INTRODUCTION: Olfactory disorders caused by medicinal drug intake are an uncommon occurrence. However, such an etiology should be systematically taken into account and investigated, as olfactory loss may be reversible once the particular treatment has been stopped. CURRENT KNOWLEDGE AND KEY POINTS: An analysis of the literature shows that of the large number of drugs that are apparently responsible for olfactory disorders, this adverse side effect has in fact only been observed in animal study populations, and no clinical case report has been made on the subject. The real toxicity to man is therefore only hypothetical. Of the 150,000 cases recorded in the pharmacovigilance centers in France, only 68 have reported olfactory complications (0.05% of cases), and only 22% of the medical files on this disorder reach a satisfactory level of plausibility. Cardiovascular drugs are mainly implicated in the development of olfactory disorders. Of these, certain drugs in particular should be mentioned: conversion enzyme (ACE) inhibitors which are responsible for taste disorders, some betablockers, and a calcium antagonist (a dihydropyridine derivative). Olfactory disorders have also been reported following administration of drugs used in anesthesia, in cancerology, endocrinology (carbimazole), in immunology (interferon), in the treatment of infectious diseases (ciprofloxacine, dioxycycline, terbinafine), and in rheumatology (D-penicillamine). FUTURE PROSPECTS AND PROJECTS: It is frequently difficult to establish a direct relationship between drug exposure and an olfactory disorder, and it is often not easy to determine with any certainty the causative role of the drug in the development of this disorder.

Animals↗

[Olfactory disorders and general pathology. Analysis and review of the literature].

INTRODUCTION: Disturbances of the sense of smell have been documented in many general pathologies. The actual etiology of such impairments is often difficult to determine. The aim of the authors is to review the literature on olfactory disorders in general diseases. CURRENT KNOWLEDGE AND KEY POINTS: Acute and chronic liver disorders are frequently associated with hyposmia, which can be improved by vitamin A intake. Renal insufficiency could induce hyposmia according to the severity of the renal disease. Olfactory disorders seem to regress after transplantation but not after dialysis. Patients with AIDS--especially neurological forms--often present with taste and smell impairments. Smell alteration can also be noted in hypothyroidism and pseudohypoparathyroidism. In addition, taste and smell impairments have been described in patients with adrenal insufficiency or Cushing's disease. Subsequent to glucocorticoid therapy, adrenal insufficiency can induce regressive olfactory hypersensitivity. Olfactory impairments in diabetic patients can be associated with diabetic macrovascular manifestations due to ischemic alterations in the olfactory neuroepithelium. Impairment of the sense of smell has been described in many systemic diseases such as Horton's arteritis and Sjögren's syndrome. FUTURE PROSPECTS AND PROJECTS: Olfactory disorders should be investigated in patients presenting one of the above-mentioned diseases.

Acquired Immunodeficiency Syndrome↗

[Description and analysis of olfactory disorders after head trauma. Review of the literature].

Olfactory disorders subsequent to head trauma can raise medicolegal problems when the olfactory deficit occurs after a work accident or a traffic accident and also raises the problem of psychological and functional tolerance when the patient consults late for a therapeutic solution. We studied the epidemiology of olfactory disorders after head trauma. Such disorders have been recognized since the XIX(th) century. Several studies have attempted to determine the prevalence of olfactory sequelae after head trauma. We then describe the pathophysiology of these lesions and emphasize that the degree of severity is related with the gravity of the head trauma and that the prevalence of these disorders varies considerably depending on the site of the trauma. Mechanisms which can lead to lesions of the olfactory system include, damage to the olfactory nerve bundles, naso-sinus lesions, or lesions of the cerebral olfactory centers. Brain MRI in anosmic patients after head trauma allows a visualization of intracranial lesions. The degree of reversibility of olfactory disorders after head trauma is imperfectly evaluated and discordant results have been reported. Some authors consider loss of olfaction is definitive. Others suggest an improvement in olfaction the year following head trauma. We reviewed the literature on these different elements. Expert opinions concerning patients complaining of olfactory disorders should relate this disorder to the initial trauma and determine the personal and occupational impact of the deficit. Attribution of cause must take into account all the clinical, radiological and psycho-olfactory factors.

Brain Damage, Chronic↗

[Olfactory disorders in Alzheimer's disease and in Parkinson's disease. Review of the literature].

Olfactory disorders in Alzheimer's disease and Parkinson's disease have been the topic of a large body of work over the last decades. Work devoted to olfactory disorders in Alzheimer's disease includes over 300 papers providing clinical and fundamental data. Anatomy studies in Alzheimer's disease have demonstrated a specific concentration of lesions in peripheral and central olfactory structures (senile plaques, neurofibrillary degeneration) as well as lesions in layers II and III of the entorhinal cortex. These neuropathological findings led to the development of the hypothesis that olfactory disorders in Alzheimer's disease would result from a toxic process. Observed olfactory deficits involve both identification and recognition of odors and detection thresholds. Nevertheless, patients with Alzheimer's disease rarely consult for sensorial deficits as the other signs of the disease predominate. Neuropathology data on the olfactory system are much more sparse in Parkinson's disease. Lewy bodies suggestive of Parkinson's disease have been observed in the olfactory bulb and pathways, but, unlike Alzheimer's disease, the olfactory disorders appear to be stable, changing little over time, as opposed to the evolution of neurological symptoms and cognition impairment. Clinicians should be aware that olfactory disorders are an integral part of Alzheimer's disease and Parkinson's disease. Screening for sensorial impairment however is a secondary objective in the context of these neurodegenerative diseases.

Alzheimer Disease↗

[Analysis of olfactory disorders in aging].

AGING EFFECT: The effect of aging on the olfactory system is generally observed in subjects over the age of 65 and is the number one cause of olfactory disorders. Several studies taking into account the state of the naso-sinus system and possible early stage of developing dementia have examined the precise effects of aging on olfaction. AGE-RELATED CHANGES: Aging affects olfactory thresholds, estimation of the intensity of an olfactory stimulation, and identification and memorization of odors. The elderly subject identifies food and other odors less easily than the young subject although elderly subjects can learn to improve their performance. Changes in the nasal cavity, particularly an alteration of the processes involved in neuron distribution in the olfactory neuroepithelium, may be involved. IMPACT OF OLFACTORY DEFICIENCY: There is much morphological and experimental evidence showing the effect of aging on both peripheral and central olfactory pathways allowing a better understanding of the functional impact of the sensorial deficit. Olfactory deficiency can explain in part the eating problems encountered in elderly patients.

Aged↗

[Magnetic resonance imaging in thoracic diseases].

Most all the thoracic structures are visible with magnetic resonance imaging: the mediastin, the myocardium including the endocardium and the pericardium, the pulmonary parenchyma and hile and the pleural walls. In cases of mediastrinal masses, T1 images clearly delimit their relations with neighbouring organs and vessels. The intensity of the signal is compared with that of the muscles on T1 weighted images of the preceding sections and T2 weighted images of fat. Images of aneurysms and chronic dissections can be synchronized with the ECG allowing three-dimensional measurement of the size and thickness of the vessel walls. Thrombi or extension to other vessels can also be recognized. Small hilar tumours can be differentiated from vessels but the scanner is better for analyzing systematization and bronchial lesions. For lung tissue itself, magnetic resonance imaging can detect nodules greater than one centimeter in diameter, but the low proton density and respiratory movements hinder spatial resolution. MRI is indicated for localizing tumours situated anteriorly or posteriorly or at the apex and to identify parietal extension of peripheral cancers. Spinal, vascular, pericardial, diaphragmatic and lymph node metastases can be recognized. MRI is the noninvasive method of choice for evaluating left ventricular masse, intra and paracardiac mass studies and for investigating congenital and acquired cardiomyopathies. Technical advances have made it possible to evaluate myocardial perfusion and heart function.

Aortic Diseases↗

[Holter monitoring. Value in silent myocardial ischemia].

The inclusion of the digital system in the Holter recording and analyzing systems and the development of micro-computers have multiplied the possibilities and increased the accuracy of this technique. Analysis of the ST segment has resulted in a definition of the silent myocardial ischaemia syndrome. It has also made it possible to evaluate the importance of myocardial ischaemia in daily life and to assess the efficacy of anti-ischaemic treatments.

Electrocardiography, Ambulatory↗

Physiology of beta-endorphins. A close-up view and a review of the literature.

When an endogenous morphine, beta-endorphin was discovered ten years ago, the fact that this morphine is present in the brain and many other tissues suggested to neurobiologists that these peptide opiates play a role which goes beyond that of a simple modulator of the perception of pain. beta-endorphin is a neurohormone which is secreted by the pituitary gland and reaches all tissues present in the body by diffusion. Many laboratories have investigated variations in serum levels of beta-endorphin under widely varying physiological or pathological conditions. Many references to these studies in the literature have thus demonstrated that beta-endorphins play a role in certain behavioural patterns (stress, alcoholism), in obesity, diabetes and psychiatric diseases. In fact, the activity of beta-endorphins would appear to have an interesting role to play and are a promising feature in the treatment of cerebral aging; in this field, beta-endorphins act not only as neuroregulators of other neurotransmitting substances but also, via calcium channels, exert an effect on the walls of cerebral arterioles. In situ, the role of beta-endorphins at the ionic channel level has been studied using the patch-clamp technique. In 1991, E Neher and B Sakmann received the Nobel Medicine and Physiology Prize for this work. beta-endorphin, which may be the "missing link" between the neuron and the wall of the arteriole, must be considered as being a fundamental neurotransmitter in the same way as well-known substances such as noradrenaline, acetylcholine, serotonin, dopamine and the GABAergic system are also neurotransmitters.

Behavior↗

High-dose chemotherapy, total abdomen irradiation and autologous bone marrow infusion in ovarian cancer: an observation.

A case of treatment of an ovarian adenocarcinoma (stage IIIc of the IFGO) is reported. The patient underwent a maximal tumor reduction followed by polychemotherapy. After this treatment, a 'second-look' laparotomy shows an incomplete remission. An intensive chemotherapy with total abdomen irradiation and protection of medullary toxicity by an autologous bone marrow infusion is performed, with a satisfactory result, without relapse, 16 months after this treatment (or 25 months after the first laparotomy). Reasons which led the authors to perform an autograft and the conditions under which this treatment may be offered are then presented.

Adult↗

[Hypertension in pregnant women and beta-blockers. Follow-up of 31 pregnancies].

The authors have conducted a study of 24 women (mean age: 28 years) whose 31 pregnancies were treated with a beta-blocker (propranolol, in most cases). The overall results were compared with data from the literature. The return to normal of the blood pressure (BP) was excellent (23 cases or 74.2%). The BP was poorly controlled in 8 out of 31 cases among which were found the 4 fetal deaths of the study. There was no toxemia, no maternal complications, no theoretical neonatal effect of the beta-blockers (nor bradycardia nor hypoglycaemia). As for fetal hypotrophy, it was more frequent when the ABP did not return to normal (57% hypotrophy vs 39%) and the beta-blocker, by causing a return to normal of the BP, decreases its incidence. In addition, the mean length of treatment exceeded 2.35 weeks in normotrophic newborns in comparison with the hypotrophic newborns. Concomitantly, the return to normal of the blood pressure is improved in normotrophic newborns. The risk of fetal hypotrophy attributed to the beta-blockers is therefore confirmed and these drugs even have a favorable effect on the birth weight.

Adult↗

[Computed tomography in thoracic pathology].

The fundamental principles of computed tomography (CT), its clinical applications and costs are presented followed by the indications and results in diseases of the mediastinum, the oesophagus, heart and great vessels, and the lung and pleura. The CT scan can give the precise localization and density of mediastinal tumours and be used to distinguish thymomas, goiters, lymph nodes, lymphomas, neurinomas and different bronchogenic and pleuropericardial cystic formations. The operability of oesophageal cancer can also be determined. In cardiovascular diseases, the CT scan is particularly useful to identify inborn anomalies, aneurysms, aortic dissection or caval compression or thrombus formation. In lung diseases, the indications for a CT scan are particularly important in bronchopulmonary cancer, tuberculosis, bronchopathies and chronic lung diseases. In bronchogenic cancer, for example, the CT scan is not only a major diagnostic tool but is also particularly useful in determining the prognosis and for following the effectiveness of treatment. The CT scan can be used to identify both effusions of liquid and gas as well as pleural reactions producing thick membranes of importance for both aetiology and later follow-up. Bronchectasis can be identified on serial sections where the degree of extension can be measured. CT scan is also indicated in patients with emphysema, both for evaluating extension and follow-up. Finally the indications and contraindications for interventional computed tomography, particularly in guiding needle biopsies, is presented.

Cardiovascular Diseases↗