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J Lacronique

Publications and source records attributed to J Lacronique.

At least 37 records · Page 2Linked to original sources

[Oral and inhaled corticoid therapy. Rivals or partners?].

Although steroids have been prescribed as antiinflammatory preparation for the treatment of asthma for many years, fear of side effects has limited their wider use. The development of new steroid derivatives administered by inhalation has reduced these risks. Oral and inhaled steroids can be used in a separate way, oral steroids being reserved for the control of acute exacerbations and inhaled steroids for the baseline treatment of chronic asthma. Inhaled and oral steroids can also be used concurrently in the same patient. Studies have shown a reduction in the dose of oral steroids in patients taking inhaled steroids. Works carried out by the Canadian research worker Toogood have addressed the question of the equivalent clinical dosing potency of inhaled and oral steroids. Finally, the reversibility of airway obstruction in subjects affected by non-specific chronic obstructive diseases might worth be assessed by using an inhaled steroid preparation.

Administration, Inhalation↗

Clinical and inflammatory responses to exogenous tachykinins in allergic rhinitis.

Our purpose was to characterize the tachykinin receptor type involved in nasal obstruction to exogenous substance P in rhinitic patients. We also attempted to assess biochemical and cellular events associated with this response. Nasal challenges were performed in seven patients with allergic rhinitis. They received increasing doses (10 to 80 nmol) of substance P, of neurokinin A, of the N-terminal fragment of substance P, substance P(1-9), and of saline on 4 different days separated by 14 days. Nasal airway resistance (NAR) increased in a dose-dependent manner on substance P. Maximal increase reached 4.5-fold basal NAR. Response to neurokinin A was significantly lower (less than 2-fold basal NAR). No effect was observed on substance P(1-9) and saline. This order of activity [substance P much greater than neurokinin A greater than substance P(1-9) = saline] indicates an NK1 receptor-mediated mechanism inducing local vasodilation. No histamine release was found after any of the four challenges. Proteins significantly increased in nasal lavage fluid on both substance P and neurokinin A, whereas substance P(1-9) and saline had no effect. The percentage of albumin increased in nasal lavage fluid from 30 to 50% of total proteins on substance P and neurokinin A, indicating microvascular leakage. Polymorphonuclear cells significantly increased from 9 to 36% on substance P, from 13 to 49% on neurokinin A, and from 13 to 55% on substance P(1-9). Eosinophils increased in five patients on substance P (from 0.1 to 5% for the group), in three patients after neurokinin A, and in two after substance P(1-9).(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

High-dose beclomethasone: oral steroid-sparing effect in severe asthmatic patients.

One hundred and twenty four patients with severe asthma requiring maintenance treatment with oral corticosteroids were included in a multicentre, double-blind, randomized study comparing the effects of inhaled beclomethasone dipropionate (BDP) (250 micrograms.puff-1), beginning with 1,000 micrograms daily, vs placebo (P). Pulmonary function was assessed and dosage of prednisone and BDP (or P) were adjusted every 15 days according to a clinical score. Our results showed, after 3 months: 1) A greater drop-out rate in the P group than in the BDP group (36 vs 6%, respectively, p less than 0.01); 2) A total weaning from prednisone in 76% of patients in the BDP group (mean BDP dosage = 1,270 +/- 340 micrograms.day-1, mean +/- SD), vs 34% in the P group (p less than 0.001). The mean daily dosage of prednisone was reduced from 17 +/- 7.5 mg to 3.1 +/- 7.4 mg in the BDP group vs 15.6 +/- 7.7 mg to 9.1 +/- 9.4 mg in the P group (p less than 0.001) without any relationship between the steroid-sparing effect and the initial dosage of prednisone; 3) Mean change in forced expiratory volume in one second (FEV1) was +7 +/- 21% from the initial value in the BDP group vs -6 +/- 20% in the P group; p less than 0.01. Thus, in patients with severe asthma requiring oral corticosteroids, high-dose BDP has an important oral steroid-sparing effect not related to the initial dosage of oral steroids and allows a better control of airway obstruction than oral corticosteroids alone.

Administration, Inhalation↗

Immunochemical characterization of corticosteroid-binding globulin in human bronchoalveolar fluid.

The corticosteroid-binding globulin (CBG) is a plasma protein which is present both in liver, where it is mainly synthesized, and in cells of different target tissues for glucocorticoids. Using monospecific antibodies raised against human CGB, we could demonstrate the antigenic identity of the protein in human bronchoalveolar fluid. We found that the bronchoalveolar fluid/serum concentration ratio of CBG was similar to that of albumin. Since albumin is not synthesized in pulmonary cells, it was concluded that, in healthy human, CBG enters bronchoalveolar fluid by diffusion through alveolar cells. It is suggested that the expression of the CBG gene in pulmonary cells could occur during the pathological state.

Blood Proteins↗

Urinary neopterin in pulmonary sarcoidosis. Relationship to clinical and biologic assessment of the disease.

Neopterin is a metabolite of guanosine-triphosphate, released in vitro by macrophages under the control of gamma-interferon and described as a marker of T cell activation in vivo. We have compared the urinary neopterin/creatinine ratio (mumol/mol) in patients with pulmonary sarcoidosis (n = 66), interstitial lung diseases other than sarcoidosis (nonsarcoid ILD, n = 35), and 45 normal control subjects. For the sarcoid population as a whole, urinary neopterin was higher (496 +/- 52 mumol/mol [mean +/- SEM]) than in control subjects (126 +/- 5 mumol/mol) (p less than 0.001). In patients with nonsarcoid ILD, urinary neopterin was frequently higher in granulomatous and/or lymphoproliferative diseases (hypersensitivity pneumonitis, tuberculosis, primitive Sjögren's syndrome, and malignant lymphomas) (781 +/- 193 mumol/mol, n = 10) but remained normal in other types of nonsarcoid ILD [( 163 +/- 14 mumol/mol, n = 25]: histiocytosis X, idiopathic pulmonary fibrosis, lung collagen-vascular diseases, diffuse neoplasms, pneumoconiosis; p less than 0.001 compared with sarcoidosis). We have also evaluated the relationship between urinary neopterin and the clinical or biologic markers currently used to assess sarcoidosis: alveolar lymphocytosis in lavage fluid (ALY), 67-gallium scan semiquantitative index (67Ga), or serum angiotensin-converting enzyme (SACE). Sarcoid patients with the highest urinary neopterin were those in whom mean values of these markers were the highest (p less than 0.05, all comparisons). Patients with positive markers (i.e., either clinical expression of sarcoidosis-ALY greater than 30%-67Ga greater than 20-SACE greater than 60 U/ml) had significantly higher urinary neopterin levels than did other sarcoid patients (p less than 0.05, all comparisons).

Adult↗

[Mechanism of action and effects of corticoids in asthma].

The value of oral or inhaled glucocorticoids (GCS) in asthma is well recognized. Their use has remained empirical for a long time. However, some progress has been achieved recently in the understanding of their general mode of action and of their bronchial effects suggesting that in the near future ther may be some new therapeutic perspectives. The fundamental action of GCS involves a close intracellular interaction between the specific glucocorticoid hormone receptor and the cellular genome which results in the activation of the genes coding the proteins responsible for the phenotypic response of the cell and thus for their biological action. The place of the extra-genomic mechanisms remains ill understood. The immunomodulating action of GCS is difficult to dissociate from their anti-inflammatory and anti-allergic effects which seem to predominate in asthma. They inhibit all stages of the inflammatory reaction in acting on the key mediators of the inflammatory response, the pharmacologically active lipids (LPA: prostaglandins, leukotrienes, PAF-acether) which are a result of the catabolism of arachidonic acid which occurs during the course of membrane activation. The phospholipid A2 (PLA2), a membrane enzyme responsible for the splitting of the phospholipids in the presence of calcium and leading to the liberation of LPA is the driving force of the reaction in such a way that the products of the nuclear activation subsequently reactivated. GCS is considered as a natural modulator of inflammation, inducing the synthesis of lipocortin, an inhibitory protein of PLA2, which explains the blockage in the generation of LPA and thus the inflammatory reaction. The regulation of the activity of these or of the lipocortin seems to lead to the intervention of the phosphorylation. But numerous questions remain concerning the precise action of PLO2, the existence of endogenous lipocortin, their secretion and their extra-cellular action. In spite of these unknown facts it is not impossible to envisage a clinical potential for lipocortin, once sequenced and produced, when the pharmacological and immunological problems have been surmounted. In asthma the effect of GCS essentially involve: the inhibition of all the bronchial components of inflammation: the synthesis, liberation and peripheral action of the mediators; the oedema and mucous congestion.(ABSTRACT TRUNCATED AT 400 WORDS)

Asthma↗

[Bronchoceles. Apropos of a case].

Bronchoceles form bronchial cul-de-sacs in normal or destroyed walls, post-stenotic or secondary to congenital bronchial atresia or infections in infancy. Because of their rarity they frequently go unrecognised. A precise history may sometimes reveal the cause as post-infectious. The differential diagnosis includes mucoid impaction and bronchial tumors. The most common radiological appearance of a bronchocele is a pulmonary opacity, posing problems of differential diagnosis with cancer; such a case is presented in this article.

Bronchial Diseases↗

Local cellular and humoral responses to antigenic and distilled water challenge in subjects with allergic rhinitis.

We studied nasal responses to allergen, saline, and distilled water aerosol in 7 subjects with allergic rhinitis to determine whether they caused a similar release of mediators and influx of inflammatory cells into the nasal lumen. The subjects were challenged first with allergen and then with aerosols of distilled water and of normal saline in random order on separate days. We measured nasal airway resistance (Rn) by posterior rhinomanometry, measured the concentrations of protein, histamine, leukotrienes (LT) B4, C4, and D4, and platelet-activating factor (PAF-acether) and performed total and differential cell counts in nasal lavage fluid obtained before and after each challenge. Allergen challenge provoked a 2-fold or greater increase in nasal airway resistance in all subjects (mean increase = 12.2-fold). This response was associated with significant increases in protein, histamine, LTB4, and sulfidopeptide leukotrienes. 2-lyso-PAF-acether increased significantly, indicating activation of phospholipase A2, but PAF-acether was detected in only one subject. The total cell count increased from 55 +/- 44 x 10(3)/ml to 200 +/- 168 x 10(3)/ml; polymorphonuclear neutrophils increased from 11 +/- 22 x 10(3)/ml to 108 +/- 96 x 10(3)/ml, and eosinophils increased from 1.3 +/- 1.8 x 10(3)/ml to 10.6 +/- 15.3 x 10(3)/ml (p less than 0.05). Saline insufflation provoked insignificant changes in mean Rn, in the levels of protein and all inflammatory mediators, and in the number and types of cells in nasal lavage fluid. Distilled water insufflation also provoked an insignificant increase in mean Rn, but there was a 14-fold increase in one subject.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

Chest radiological features of pulmonary histiocytosis X: a report based on 50 adult cases.

This study describes the chest radiographs of 50 adult patients with histologically verified histiocytosis X, proposes a radiological classification, and examines the role of radiology in assessing the prognosis of the disease. Radiologically the lesions predominate in the middle and lower lung fields, usually sparing the costophrenic angles, and are typically micronodular, reticular, or cystic. These features are especially suggestive of histiocytosis X if lung volume is normal or increased, there is an associated pneumothorax, they occur in a young male and there are no other intrathoracic changes (pleural or mediastinal). The three evolutionary patterns of improvement, stabilisation, and worsening are analysed with respect to the initial radiological features; one which carries a good prognosis is sparing of both costophrenic angles.

Adolescent↗