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Biomedical subjects

B Wallaert

Publications and source records attributed to B Wallaert.

At least 199 records · Page 11Linked to original sources
PubMed1992

Tumor necrosis factor alpha and interleukin-6 production by human mononuclear phagocytes from allergic asthmatics after IgE-dependent stimulation.

We have previously demonstrated the production of tumor necrosis factor alpha (TNF) and interleukin-6 (IL-6) by alveolar macrophages (AM) from allergic asthmatics developing a late asthmatic reaction after bronchial allergen challenge. In order to explain the modalities of this monokine synthesis, we tested in vitro the effect of an IgE-dependent stimulation on blood monocytes (BM) and AM from control and asthmatic subjects. TNF and IL-6 secretions were evaluated in 24-h supernatants by radioimmunoassay and by the 7TD1 cell proliferation test, respectively. AM from allergic asthmatics secreted spontaneously higher concentrations of TNF and IL-6 than did BM or AM from control subjects. BM from asthmatics also produced spontaneously increased levels of TNF, but at a lesser degree than did AM. The addition of anti-IgE induced a significant increase of TNF and IL-6 secretions by mononuclear phagocytes from control subjects only after previous sensitization with IgE-rich medium. In contrast, the direct stimulation by allergen or anti-IgE of AM and BM from asthmatics enhanced significantly the production of TNF and IL-6 when compared with cells cultured in medium alone. In these conditions, IgE-dependent activation of cells from allergic asthmatics compared with those from control subjects increased monokine production in a similar manner. Costimulation by recombinant human interferon gamma and IgE-dependent triggering had a synergistic effect on TNF production, but it had only an additive action on IL-6 synthesis (respective increase index: 9.8 compared with 2.9 and 9.8 compared with 2.1, respectively, for BM from control and asthmatic subjects).(ABSTRACT TRUNCATED AT 250 WORDS)

Asthma↗
PubMed1992

Bronchoalveolar lavage in alcoholic liver cirrhosis. T-lymphocyte subsets and immunoglobulin concentrations.

The purpose of this study was to determine the phenotype profiles of immune effector cells and the concentrations of immunoglobulins in the lower respiratory tract of non-smoking patients with alcoholic liver cirrhosis (ALC). Nine nonsmoking patients with liver biopsy-proved ALC (grade B or C cirrhosis in Child's classification), free of clinical pulmonary symptoms, and with normal chest roentgenogram were included in the study. The control group included 12 healthy nonsmokers. Each patient had fiberoptic bronchoscopy with bronchoalveolar lavage (BAL). The number of T cells and of lymphocyte subpopulations was determined by immunofluorescence studies using monoclonal antibodies that were specific for CD3, CD4, and CD8 markers. Patients with ALC exhibited a dramatically increased percentage of CD8+ cells in BAL that induced a low CD4/CD8 ratio (0.96 +/- 0.15 vs 1.8 +/- 0.12 in healthy controls). Further characterization of lymphocyte subsets' dual immunofluorescence analysis demonstrated that most of the CD8+ alveolar lymphocytes had a phenotype of cytotoxic cells (CD8+ CD11b-; 48 percent +/- 13 in ALC vs 10 percent +/- 5 in controls). ALC was associated with an appreciable alveolar-capillary "leak" as demonstrated by a significant increase in BAL fluid albumin. In addition, the concentrations of immunoglobulins in BAL fluid were significantly greater in ALC than in controls. However, the relative (to albumin) coefficient of excretion of IgG, A, and M in and alpha 2-macroglobulin BAL fluid was not significantly different between controls and ALC. Our results indicate that increased proportions of CB8+ and especially of CD8+ CD11b- cells are a common feature in the lower respiratory tract of nonsmoking patients with ALC. These changes may be of potential functional importance in the regulation of the local pulmonary immune response in ALC.

Adult↗
PubMed1992

[The multifocal form of bronchocentric granulomatosis].

Bronchocentric granulomatosis is a rare entity and has only recently been characterised. We report a case of a forty-three year old man presenting with multifocal bronchocentric granulomatosis which was revealed following some oto-rhino-laryngological and bronchopulmonary symptoms. The open lung biopsy confirmed the diagnosis. Treatment was by bolus doses of corticosteroids (30 mg/kg) and of methotrexate in low dosage (7.5 mg/week, then 15 mg/week) which checked the initially unfavourable outcome.

Adrenal Cortex Hormones↗
PubMed1992

[Broncho-alveolar lavage. From technical aspects to standards of interpretation].

Broncho-alveolar lavage is a simple investigation to carry out and enables the gathering of biological information such as inflammatory and immuno-competent cells, tumour cells, microorganisms as well as mineral particles which are found in the biological milieux present in the distal air spaces. The performance of LBA assumes a mastering of the correct technical aspects of this method of investigation, particularly in the phase of injecting and recovering of physiological saline and an understanding of the indications and contraindications of the technique. The interpretation of the information gathered by cytological, microbiological, mineralogical and biochemical study of the bronchoalveolar lavage liquid should comply with a strict set of rules and justifies a close working contact between the clinician and the biological scientist.

Bronchi↗
PubMed1992

[Occupational dust exposure and chronic obstructive bronchopulmonary disease. Etiopathogenic approach to the problem of compensation in the mining environment].

In order to support the hypothesis of a causal relationship between exposure to respirable coal mine dusts and chronic obstructive pulmonary disease (COPD), investigations were performed to assess the biological disorders affecting the distal air spaces in coal workers with pneumoconiosis. Broncho alveolar lavage studies demonstrated a continual influx of mononuclear phagocytes loaded with mineral particles, associated with neutrophils in small number, in smokers as well as in non smokers. The alveolar macrophages were in activated state, spontaneously releasing various mediators, particularly interleukin I, Tumor necrosis factor alpha and superoxide anion. So, they appeared as responsible both for a chronic inflammation of the distal airways and for a protease-antiprotease imbalance leading to pulmonary emphysema, partly due to an oxidative inactivation of alpha 1 antiprotease inhibitor. In spite of additive effect of tobacco smoke, as shown by longitudinal studies of lung function in coal miners, it is now reasonable to consider the evidence of association between coal mine exposure and COPD to be sufficiently strong to infer causality, and to justify compensation for COPD in coal miners with or without radiological evidence of pneumoconiosis.

Coal↗
PubMed1991

[Value of bronchoalveolar lavage in the diagnosis and management of diffuse interstitial fibrosing lung diseases].

Bronchoalveolar lavage (BAL) is an exploratory technique which is easy to perform and collect cellular constituents, notably inflammatory and immunocompetent cells, as well as biological elements that are present in the distal airways. In patient with chronic diffuse infiltrative lung disease, analysis of these parameters reveals various disturbances such as neutrophilia frequently associated with eosinophilia and, in some cases, lymphocytosis. These features are not specific, but they differentiate chronic diffuse infiltrative lung diseases from sarcoidosis and hypersensitivity lung diseases. Alveolar inflammation (alveolitis) correlates with the evolutive potential of the lesions and their ability to respond to treatment. The presence of lymphocytosis is usually associated with response to corticosteroid therapy, whereas the presence or persistence of neutrophilia and, even more, eosinophilia is characteristic of patients who do not respond to corticosteroids but are amenable to the cyclophosphamide-corticosteroid combination. BAL therefore increasingly appears as an irreplaceable tool to understand the physiopathology of chronic diffuse infiltrative lung diseases.

Bronchoalveolar Lavage Fluid↗
PubMed1991

Increased secretion of tumor necrosis factor alpha and interleukin-6 by alveolar macrophages consecutive to the development of the late asthmatic reaction.

The late asthmatic reaction (LAR), consecutive to bronchial allergen challenge, is characterized both by the influx of various cells in proximal and distal airways and by the enhancement of bronchial hyperresponsiveness. However, the exact conditions for the development of the inflammatory reaction during the LAR remain to be specified. Since monokines play a key role in inflammatory processes, particularly in the lung, the production of tumor necrosis factor-alpha (TNF-alpha), interleukin; 1-beta (IL-1-beta) and interleukin-6 (IL-6) by alveolar macrophages (AM), collected 18 to 20 hours after exposure to allergen, was evaluated in 15 allergic subjects with asthma submitted to a challenge test with Dermatophagoides pteronyssinus (N = 6) or with wheat flour (N = 9) and in three healthy subjects. After bronchial provocation test, four patients presented no bronchial response (group 1), and six patients, a single early reaction (group 2). In contrast, five patients developed successively an immediate plus a late response (group 3). The monokine production was compared to that from nine allergic subjects with asthma studied at baseline (group 0) and from 11 unchallenged healthy subjects (control subjects). Measurements of cytokines were evaluated for TNF-alpha and IL-1-beta by a specific immunoradiometric assay, whereas IL-6 levels were appreciated by the proliferation of 7TD1 cells. No detectable amounts of TNF-alpha, IL-1-beta, and IL-6 were in bronchial alveolar lavage fluid, even after a tenfold concentration. In contrast, a significant increase of TNF-alpha (10,642 +/- 3127 U/ml) and IL-6 (1250 +/- 427 U/ml) concentrations was noted in AM supernatants from patients exhibiting an LAR (group 3) compared to cells recovered from groups 2, 1, and 0 and to challenged or unchallenged control subjects (805 +/- 244, 995 +/- 521, 1269 +/- 524, 688 +/- 85, and 445 +/- 74 pg of TNF-alpha per milliliter, respectively; 190 +/- 64, 114 +/- 91, 242 +/- 95, 80 +/- 9, and 54 +/- 19 U/ml of IL-6 per milliliter, respectively). No modification of IL-1-beta contents could be detected between the different groups. A significant correlation was detected between concentrations of TNF and IL-6 (r = 0.92; p less than 0.001). These results demonstrate TNF-alpha and IL-6 secretion by AM consecutively to the development of LAR in allergic subjects with asthma, confirming that AMs are activated after allergen challenge.(ABSTRACT TRUNCATED AT 400 WORDS)

Adult↗
PubMed1991

Human alveolar macrophage antibacterial activity in the alcoholic lung.

Alcoholic individuals are predisposed to respiratory infections. However, mechanisms of perturbations leading to increased susceptibility to lung infections of individuals with alcoholic liver cirrhosis (ALC) are not fully understood. We studied the antibacterial activity and oxidant generation (before and after stimulation by phorbol myristate acetate or opsonized zymosan) of alveolar macrophages from 16 patients with ALC. Our results were compared with those obtained from 12 healthy control subjects, from 8 patients with primary biliary cirrhosis (PBC), and from 8 alcoholic individuals without cirrhosis. All were nonsmokers, had normal chest X-rays, and did not present evidence of lung infection 3 months before. The total number of cells recovered by bronchoalveolar lavage did not significantly differ between control subjects and patients. The cellular viability of alveolar macrophages (trypan blue exclusion) was greater than 90% in all cases. The antibacterial activity of alveolar macrophages versus Staphylococcus aureus was severely impaired in ALC (-21 +/- 8.2%) whereas it was normal in PBC (52 +/- 4.2%), in alcoholic subjects (44.6 +/- 5.4%), and in control subjects (60 +/- 5.5%). The same pattern of results was observed versus Escherichia coli (-47.7 +/- 10,28 +/- 8,28 +/- 12, and 29 +/- 8.5%, respectively). Previous incubation of normal alveolar macrophages with serum or BAL fluid from ALC patients or with normal serum or normal BAL fluid did not result in a significant decrease in antibacterial activity of normal alveolar macrophages. To distinguish ingested bacteria from adherent extracellular bacteria, cells that had been incubated with bacteria for 90 min were then incubated with lysostaphin (1 microgram/ml).(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1991

Production of tumor necrosis factor-alpha and interleukin-6 by human alveolar macrophages exposed in vitro to coal mine dust.

Following our previous demonstration of cytokine secretion by alveolar macrophages (AM) from coal miners and from patients with coal workers' pneumoconiosis, we investigated the effect of in vitro exposure to coal dust and to its silica content on tumor necrosis factor-alpha (TNF), interleukin (IL)-1 beta, and IL-6 production by normal human AM. TNF and IL-1 beta concentrations were estimated by a specific radioimmunoassay, while IL-6 levels were evaluated by the proliferation of 7TD1 cells. After 24-h culture, coal dust triggered a significant release of TNF and IL-6 at the dose of 0.1 mg/ml and more obviously at 1 mg/ml in comparison with titanium dioxide (TiO2), used as a biologically inert control dust (with 1 mg/ml of dust: 3,526 +/- 3,509 versus 330 +/- 138 pg TNF/ml and 224 +/- 74 versus 72 +/- 34 U IL-6/ml, respectively; P less than 0.01 in both cases). After 3-h culture, a significant TNF secretion as well as an increased TNF mRNA expression were also detected for AM stimulated by coal dust at variance with TiO2. In contrast, no modification of IL-1 beta concentration could be evidenced in AM exposed to coal dust, although we detected an increased expression of specific mRNA expression. In order to define the role of silica among the main components of coal dust in AM activation, we evaluated the effect of silica (alpha-quartz, 30 micrograms/ml, which is the concentration and the type of silica present in our coal dust) alone or mixed with TiO2 (1 mg/ml) on monokine production.(ABSTRACT TRUNCATED AT 250 WORDS)

Cells, Cultured↗
PubMed1991

Oxidative inactivation of alpha 1-proteinase inhibitor by alveolar macrophages from healthy smokers requires the presence of myeloperoxidase.

The aim of this work was to study the ability of human alveolar macrophages (AM) of 10 healthy smokers to inactivate alpha 1-proteinase inhibitor (alpha 1PI). Purified alpha 1PI was incubated for 45 min, with human alveolar macrophages before and after stimulation by phorbol myristate acetate (PMA) or opsonized zymosan. As a positive control, the same experiments were performed in parallel with blood human neutrophils (PMN). Results are expressed as percentage of inactivation of alpha 1PI as evaluated from its inhibitory activity against porcine pancreatic elastase. A strong correlation (r = 0.99) was shown when inhibitory activity of alpha 1PI was evaluated against porcine pancreatic elastase or human neutrophil elastase. Unstimulated AM (1.57 +/- 0.9%) as well as stimulated AM (PMA: 1 +/- 0.4%; zymosan: 3 +/- 0.6%) were unable to inactivate alpha 1PI. Gel electrophoresis of alpha 1PI demonstrated that AM before or after stimulation induced a slight proteolysis of alpha 1PI, whereas both cleaved and complexed alpha 1PI were found when alpha 1PI was incubated with activated PMN. Both unstimulated (22 +/- 2.6%) and activated PMN (PMA: 91.7 +/- 4.7%; zymosan: 90 +/- 5.5%) were responsible for a significant inactivation of alpha 1PI. Catalase, in contrast to superoxide dismutase, was responsible for a near complete protection of alpha 1PI inactivation by PMN. To better determine the role of PMN secretory products, especially myeloperoxidase (MPO), we also investigated the effect of zymosan-activated PMN supernatants or of purified MPO on the alpha 1PI-AM reaction. MPO assay in PMN supernatants demonstrated that activated neutrophils released significant amounts of MPO (16.8 +/- 4.1 U/ml), whereas MPO was undetectable in activated AM supernatants.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1991

Metastatic prostatic adenocarcinoma-diagnosed by bronchoalveolar lavage and tumour marker determination.

We report a patient who presented with a diffuse interstitial lung disease in whom clinical and radiologic investigation led to the suspicion of lymphangitis carcinomatosa. Bronchoalveolar lavage (BAL) was performed and revealed the presence of prostatic specific antigen (PSA) positive cells. A prostatic needle aspiration confirmed the diagnosis of adenocarcinoma. This case demonstrates the value of tumour marker determination in BAL.

Adenocarcinoma↗
PubMed1991

[Study of high-resolution thoracic computerized tomography and bronchoalveolar lavage in 36 patients presenting with systemic disease and a normal thoracic radiography].

Systemic diseases such as scleroderma (ScI), rheumatoid polyarthritis (PR), Gougerot-Sjögren Syndrome (GS) have a well known propensity for the lungs. Previous studies have shown evidence of disturbed alveolar cell repair as evidence of a sub-clinical alveolitis. The significance of such cases of latent alveolitis remains to be specified. To determine if latent alveolitis was associated with interstitial chest disease which was undetectable by chest X-ray, 36 consecutive patients had an BAL and a high resolution computered tomographic examination (HRTC) (Scl: n = 21; PR: n = 9; GS: n = 6). The patients had normal respiratory function and chest X-ray was normal. Our results showed 17 out of 36 (47%) with a latent alveolitis (the percentage of lymphocytes and of alveolar polymorpho-nuclear neutrophils was superior or equal to 18 and 4% respectively) (Scl: 12/21; PR: 1/9; GS: 4/6). In the cases of scleroderma a neutrophil alveolitis was predominant (9/12) and was associated in 2 cases with a honeycomb lung and evidence of fibrotic lesions using TDM-HR. Those examinations using HRTC which were normal were equally associated with a latent alveolitis (Scl: 6/12; PR: 1/6; GR: 4/5). These results suggest that the alveolitis can preceed the anatomical damages. These results need to be confirmed in a larger series and the value of early treatment should be evaluated.

Adolescent↗
PubMed1991

Neutrophil-endothelial cell interaction: evidence in vitro for a regulation by endothelial cells of neutrophil functions.

The purpose of this study was to investigate a possible relationship between human umbilical vein endothelial cells (EC) triggered by ionophore A23187 at different doses (0.5-2.5 microM) and polymorphonuclear neutrophils (PMN). EC supernatants were shown to contain neutrophil chemoattractant activity (NCA) and in parallel a factor inducing an inhibition of PMN chemiluminescence (PMN CL). Supernatants obtained from EC triggered by A23187 exhibited a high level of NCA (73 +/- 5 PMN.hpf-1 compared to 21 +/- 4 PMN.hpf-1 in untreated EC supernatants, p less than 0.01). This NCA was independent from arachidonic acid metabolites, since indomethacin and nordi-hydroguaiaretic acid failed to suppress the chemotactic activity. Using gel filtration chromatography (AcA 54) the NCA was recovered in a single peak of apparent molecular weight of 37,000 +/- 4,000 daltons. Checkerboard analysis indicated that NCA exhibited both chemotactic and chemokinetic activities. In addition, supernatants of A23187-stimulated EC, and at a lesser degree, supernatants of unstimulated EC, inhibited PMN CL induced by N-formyl-Methionyl-Leucyl-Phenylalanine (61% inhibition, p less than 0.05), and by A23187 itself (80% inhibition, p less than 0.01), but not that induced by phorbol-myristate-acetate. Indomethacin and protamine sulphate did not modulate this inhibitory activity. By contrast, EC-derived inhibitory activity was inhibited (50%) by an adenosine antagonist (8-phenyltheophylline), indicating a participation of adenosine in this inhibitory activity of PMN CL. These data suggest the possibility that activated endothelial cells could both enhance PMN migration and protect themselves against potential damaging effects of oxygen metabolites produced by PMN, particularly during transvascular migration.

Calcimycin↗
PubMed1991

[Pleuro-pulmonary manifestations of rheumatoid polyarthritis].

Sensitive investigations such as pulmonary function tests, broncho-alveolar lavage or computered tomography at high resolution enable pleuro-pulmonary disease to be detected in nearly 50% of those patients studied who had rheumatoid arthritis (PR). The prevalence of these manifestations is most usually elevated in male PR sufferers, those who are sero-positive or have associated extra-articular signs such as sub cutaneous nodules. More recently there has been evidence of genetic risk factors linked to HLA grouping or Pi phenotype. Amongst the usual manifestations, the pleurisies and above all necrobiotic nodules, which are most often asymptomatic, sometimes pose difficult problems in differential diagnosis, particularly when they precede the articular disease. The diffuse interstitial fibrosis remains the most worrying specific complication due to the fact of its potential seriousness. The pathophysiology of this form of fibrosis is better understood since the introduction of LBA. In the absence of any specific controlled studies its treatment remains impirical and is similar to that given for diffuse or idiopathic interstitial fibrosis. Pulmonary vascularity, the bronchiolitis obliterans with organising pneumonia and apical fibrosis, very similar to Hamilton's syndrome, are much rarer manifestations. On the other hand non specific respiratory infections are the cause of death in 10-20% of cases. Bronchiolitis obliterans induced by D Penicillamine is the most severe iatrogenic manifestation, since corticosteroid therapy associated with immunosuppressive drugs enables at best a stabilisation of the alveo bronchiolar lesions. More recently there have been twenty observations of hypersensitivity pneumonia to low dose methotrexate. The prevalence of these pulmonary disorders during the treatment of PR is around 5%. However the respiratory contraindications of these drugs which are being used more and more and the methods of pulmonary surveillance under treatment are not yet defined.

Arthritis, Rheumatoid↗
PubMed1991

[Auricular chondritis, malignant glomerulonephritis and pulmonary hemorrhage].

Relapsing polychondritis is a rare connective tissue disorder characterized by inflammation of cartilagenous structures such as ears, nose, joints, trachea and larynx. Renal disease is unusual. A 41 years old man presented with auricular chondritis, subacute renal failure and lung hemorrhage. A renal biopsy disclosed a diffuse proliferative glomerulonephritis with extensive crescents. Immunofluorescent studies suggested a GNRP type III so called "non immunologic disease". He was treated by prednisone and plasmapheresis with rapid disappearance of pulmonary hemorrhages and good renal functional improvement.

Adult↗
PubMed1991

[Mediastinal adenopathy disclosing Castleman's disease. Apropos of a case].

Castleman's disease or pseudo-tumoral lymphoid hyperplasia is a rare entity. We report a case of Castleman's tumour in the antero-superior mediastinum which was revealed by a radiological examination in a young woman of 26. We also report immunohistochemical studies. There are two clinical presentations of Castleman's disease; a localised form (mediastinal or extrathoracic) and the multicentric variety. The localised form may be asymptomatic or can be accompanied by general features of inflammatory disease. Surgical excision of these localised forms both confirms the diagnosis and assures a cure. The multicentric variety has various clinical peculiarities (the patients are older and/or immunosuppressed and suffering from multiple enlarged glands also in the viscera) and the disease in above all progressive. There are associations with Kaposi sarcoma and lymphoproliferative complications are described in this multicentric form and their prognosis remains poor.

Adult↗
PubMed1991

[In vivo kinetics of cotrimoxazole in alveolar macrophages].

The aim of this work was to study the kinetic of intramacrophage penetration of cotrimoxazole in guinea pigs which had received 100 mg/kg of sulfamethoxazole and 20 mg/kg of trimethoprim after a single intraperitoneal injection. 30 minutes, 1, 3, 6 and 24 hours after this injection an intra-cardiac blood sample was taken and pulmonary lavage was performed immediately after sacrificing the animal by cervical cord dislocation. The level of trimethoprim and sulfamethoxazole was measured in each sample by high performance liquid chromatography (HPLC). An estimation of the dilution of the supernatant was obtained by comparing the supernatant glucose with the serum glucose. The serum kinetics of trimethoprim and sulfamethoxazole progressed in a parallel fasion with time with a maximal concentration at 30 minutes (for trimethoprim: 6.7 +/- 0.9 micrograms/ml and for sulfamethoxazole 176.1 +/- 16.2 micrograms/ml). On the other hand their penetration capacity was different in the supernatant and in the alveolar macrophages: the maximal concentrations were obtained after one hour in the supernatant and after 3 hours in the cellular extract and were respectively for trimethoprim 0.43 +/- 0.07 microgram/ml and 20.9 +/- 8.06 micrograms/ml of intramacrophage water and for sulfamethoxazole 1.86 +/- 0.24 micrograms/ml and 23.8 +/- 12.7 micrograms/ml of intramacrophage water. A concentration around six times greater was noted for the trimethoprim inside the cells compared with serum and was only 0.25 time for sulfamethoxazole. On the other hand the supernatant/serum ratio showed a greater concentration for trimethoprim (4 to 10) than for sulfamethoxazole (0.6 to 1).(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗