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P Chanez

Publications and source records attributed to P Chanez.

193 records · Page 11Linked to original sources
PubMed1989

[Pulmonary opacities in the shape of ribbon streamers. Apropos of a case].

The authors report a case of chronic interstitial pneumonia with a very unusual appearance (on plain films and CT); in fact such ribbon-like linear opacities with concentric and pseudo-cavitary disposition have not been previously described. They are comparable but different from the linear opacities described by Carrington in some cases of chronic eosinophilic interstitial pneumonia, which are vertical and peripheral. They are also different from the curvilinear sub-pleural opacities reported in some cases of asbestosis. On the basis of the anatomic findings they discuss the specificity of such radiologic patterns or their sole value as an evolutive state.

Female↗
PubMed1988

Spontaneous and non-specific release of histamine and PGD2 by bronchoalveolar lavage cells from asthmatic and normal subjects: effect of nedocromil sodium.

Mast cells have been implicated in the pathogenesis of allergic asthma but their role in non-allergic asthma remains to be elucidated. The spontaneous and non-specific release of histamine by suboptimal doses of calcium ionophore A23187 was studied in bronchoalveolar lavage cells obtained from nine asthmatic and seven healthy individuals. Bronchoalveolar lavage was performed with saline, and total cells were incubated without any secretagogue (spontaneous histamine release) or after addition of 1.25, 2.5 and 5 microM of A23187 for 30 min (net maximal release). Histamine was titrated by using a very sensitive radioimmunoassay using a monoclonal antibody against acylated histamine. The spontaneous release was similar in asthmatic (20.6 +/- 8.2%) and healthy individuals (17.4 +/- 8.4%). The net maximal release of histamine was significantly greater in asthmatic patients (28.1 +/- 17.4%) than in normal subjects (10.3 +/- 8.9%). The release of histamine was significantly correlated to the release of PGD2 measured by enzyme immunoassay using a polyclonal antibody against methoxamine-PGD2 (Spearman rank test: 0.78, P less than 0.01). In eight subjects, the release of histamine by A23187 was studied in the presence of nedocromil sodium and it was observed that this drug significantly (P less than 0.05) decreased the net maximal release of histamine. This study shows that mast cells from asthmatic individuals have a greater releasability than those of normal subjects.

Adult↗
PubMed1988

Kaposi's sarcoma of the bronchial tree in a renal transplant recipient.

An unusual case of disseminated Kaposi's sarcoma with endobronchial lesions is presented; these localizations are quite uncommon in the course of the disease, particularly in kidney transplant recipients. Some of the multifactorial etiologies of Kaposi's sarcoma are present: immunosuppression, ethnic origin and CMV infection. We emphasize that the diagnosis of bronchial involvement can be made during fiberoptic bronchoscopy and confirmed by biopsy without excessive complications.

Bronchial Neoplasms↗
PubMed1988

Approaches to the diagnosis of viral pneumonias in the immunocompromised host: the importance of assaying cytopathogenic viral effects in bronchoalveolar lavage cells.

Pneumonopathic conditions in the immunocompromised host (IH) are frequent and often serious. Rapid diagnosis is essential and is made possible by bronchoalveolar lavage (BAL). Sixty-two pneumonopathic episodes in 53 immunocompromised patients were examined by BAL, for viral cytopathogenic effects (CPE) in isolated cells, with appropriate viral culture techniques. Viral culture was positive in seventeen of the eighteen episodes in renal allograft recipients and AIDS patients as against eight of the fourty-four episodes in other causes of IH (p less than 0.001). CPE was found thirteen times; in seven cases it was characteristic of cytomegalovirus. Positive viral culture and CPE were shown simultaneously during thirteen episodes in eleven patients. Ten patients died (autopsies performed in three cases confirmed viral presence). Positive viral culture with absence of CPE was observed in twelve cases. There were only four fatalities in this group (the autopsies performed in three cases did not establish the presence of a virus in the pulmonary parenchyma). The percentage of lymphocytes was high in both groups of patients (18.6 +/- 2.8%). CPE is a simple and rapid examination for the diagnosis of viral pneumonopathology in the IH. Prognosis at present is gloomy; more complex examinations such as viral cultures and/or identification of the virus by immunofluorescence will be indicated only when effective antiviral agents become available.

Acquired Immunodeficiency Syndrome↗
PubMed1988

Platelet-activating factor induces eosinophil peroxidase release from purified human eosinophils.

The degranulation response of purified human eosinophils to platelet-activating factor (PAF) has been studied. PAF induced release of eosinophil peroxidase (EPO) and beta-glucuronidase from highly purified human eosinophils with an EC50 of 0.9 nM. The order of release was comparable with that induced by phorbol myristate acetate (PMA). The new specific PAF antagonist 3-[4-(2-chlorophenyl)-9-methyl-H-thieno[3,2-f] [1,2,4]triazolo-[4,3a][1,4]-diazepin-2-yl](4-morpholinyl)- 1-propane-one (WEB 2086) inhibited the PAF-induced enzyme release by human eosinophils in a dose-dependent manner. The viability of eosinophils were unaffected both by PAF and WEB 2086. The results suggest that PAF may amplify allergic and inflammatory reactions by release of preformed proteins from eosinophil granules.

Azepines↗
PubMed1987

Enhanced alveolar cell luminol-dependent chemiluminescence in asthma.

Alveolar macrophages (AM) appear to be one type of cells of the bronchial inflammation often involved in patients with asthma. These cells were demonstrated to generate highly reactive toxic species of oxygen in many pulmonary disorders; however, this was never demonstrated in asthma. The respiratory burst of bronchoalveolar lavage AM was studied in 12 subjects with asthma and in five control subjects by luminol-enhanced chemiluminescence (Cl). Both in subjects with asthma and in healthy subjects, the maximal value of Cl was obtained after 10 to 13 minutes of stimulation by opsonized zymozan. Baseline values and maximal Cl of AM values were significantly increased (p less than or equal to 0.03 and p less than or equal to 0.01) in subjects with asthma. There was a significant (p less than or equal to 0.01) correlation between maximal Cl of AM and the severity of asthma, assessed by a clinical score defined by Dr. K. Aas. The percentage of bronchoalveolar lavage eosinophils was significantly correlated (p less than or equal to 0.01) for all the subjects with the peak of CL of AM. This study suggests the role of toxic oxygen species in the bronchial inflammation in asthma.

Adult↗
PubMed1987

[Oxygen free radicals and bronchial asthma].

Oxygen free radicals are released generally by many cells during phagocytosis and cell activation. In asthmatics, some experimental evidence indicates that oxygen free radicals may be considered to be chemical mediators of anaphylaxis. They are released by macrophages, eosinophils and neutrophils, the cells that are found in bronchoalveolar lavage. They may explain some pathological changes, such as hardening of the airways, bronchial hyper-reactivity and inflammation. Therapeutic implications are discussed.

Adolescent↗
PubMedDate not supplied

Imaging reactive oxygen species in asthma.

Inflammatory processes in asthma are characterized by an infiltration of inflammatory cells including mononuclear phagocytes. It has been observed that mononuclear phagocytes, alveolar macrophages and blood monocytes, release higher quantities of reactive oxygen species in asthmatic patients than in healthy subjects. Chemiluminescence assays were developed to measure the superoxide anion and the other reactive oxygen species. The chemiluminescence response was first analysed with a luminometer, which made it possible to study cells in suspension before and after PMA-stimulation. Secondly a video-imaging camera was used in experiments on adherent cells before and after stimulation with PMA and/or specific stimulus IgE/anti-IgE. Both techniques showed that human alveolar macrophages, blood monocytes, PMN and lymphocytes were spontaneously primed in vivo and were more easily stimulated in asthma. Analysis of adherent cells in vitro may provide give information on the physiological condition of adherent cells in vivo.

Acridines↗
PubMedDate not supplied

Induction of nitric oxide synthase in asthma.

Nitric oxide (NO) is a mediator of vasodilatation and bronchodilatation synthesised from L-arginine by the enzyme NO synthase, which is either constitutive or induced by lipopolysaccharides and/or cytokines. The presence and function of NO synthase in normal or diseased lung is not yet clear. Asthma is characterised by bronchial hyperresponsiveness, epithelial damage, inflammation, and increased cytokine production. To investigate the presence of NO synthase in asthma, we immunostained bronchial biopsies from non-steroid-treated people with asthma and non-asthmatic controls with specific polyvalent antisera to purified inducible NO synthase and to a selected peptide sequence of the same enzyme. Immunoreactivity was seen in the epithelium and some inflammatory cells in 22 of 23 biopsies from people with asthma, but in only 2 of 20 controls. To assess the relation of cytokines to NO synthase induction, bronchial epithelial cells in culture were stimulated with tumour necrosis factor (TNF alpha). Inducible enzyme immunoreactivity was found only in the treated cells. The existence of inducible NO synthase in human lungs suggests that increased production of NO, probably induced by cytokines, may be relevant to the pathology of asthma.

Adult↗
PubMedDate not supplied

Airways remodelling in asthma: no doubt, no more?

Asthma is a chronic inflammatory disease of the airways invariably associated with healing. Remodelling of the airways can be demonstrated by the activation of airways macrophages, the release of growth factors and fibrogenic cytokines, the activation of fibroblasts and myofibroblast, elastolysis and elastosynthesis, collagen deposition, increased synthesis and release of extracellular matrix components, and an increased mass of smooth muscle and mucous glands. However, the control of remodelling is still poorly understood.

Asthma↗