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Biomedical subjects

B Wallaert

Publications and source records attributed to B Wallaert.

At least 253 records · Page 14Linked to original sources
PubMed1988

Bronchoscopic protected catheter brush for the diagnosis of pulmonary infections.

A new bronchoscopic-protected catheter brush (BPCB), designed to obtain uncontaminated bronchial secretions, was studied in vitro and in vivo. The device was composed of a standard biopsy brush, protected by a single catheter and occluded with an agar plug. Ejection of the plug was obtained neither by advancing the brush nor by advancing an inner cannula (as in a telescoping catheter brush), but instead, by an air flux, provided by a syringe which was connected to the proximal tip. In the first part of the study the ability of the BPCB to obtain uncontaminated specimens was tested in comparison with the reference telescoping catheter brush (BFW brush 10/70/90, Medi-Tech Corp Watertown, MA). Catheters of each type were successively passed through the inner channel of a bronchofiberscope which was contaminated with Klebsiella pneumonia. After ejection of the distal plug, sampling of bronchial secretions infected with a marker organism (Pseudomonas aeruginosa), was performed with the brush. Culture of brush specimens of each type of catheter grew the marker organism in pure culture and obtained the same amount of bronchial secretions (0.001 ml). The manual vortexing of the brush in the transport medium (Ringer's solution) proved to be as effective as the mechanical vortexing so that transecting of the brush was no longer mandatory. In the second part of this study, paired bronchial samplings from 27 patients were performed using both types of catheters and similar results for both were obtained. In these in vitro studies, completed by a clinical trial, our single-sheathed, plugged catheter brush proved to be as reliable as the double telescoping catheter brush. However, because of its relatively simple conception, making it easier to use and lower in cost than the double catheter brush, routine use of this sampling device should be considered.

Biopsy↗
PubMed1988

[Invasive thymoma with pulmonary metastasis. Complete remission 5 years after surgery and chemotherapy using the CHOP-BLEO protocol].

We report a case of invasive lympho-epithelial thymoma with pulmonary metastases, treated by complete macroscopic excision of primary tumour and then by chemotherapy using CHOP-BLEO. The epithelial nature of the tumour was confirmed by immunohistochemical studies. Chemotherapy enabled a complete and prolonged remission (greater than 63 months). Therapeutic trials of CHOP-BLEO merit further assessment and the results should be compared to the baseline treatment using platinum and prednisolone.

Adolescent↗
PubMed1988

[Interstitial pathology and pregnancy].

Pregnancy is an important factor in the outcome of interstitial pneumonias. The outcome for sarcoidosis and rheumatoid disease is favourable as a rule, and these disorders have little influence on the progress of the disease. Idiopathic pulmonary fibrosis or fibrosis complicating scleroderma or dermatopolymyositis requires careful management considering the frequent complications at foetal level. During systemic disorders, recourse to corticosteroid-cyclophosphamide regime is possible from the second trimester. Drug induced pneumonias remain rare, do not influence pregnancy and most often only require the arrest of the incriminated drug.

Female↗
PubMed1988

[Vaso-occlusion of the pulmonary artery].

Vaso-occlusion of the pulmonary artery is an angiographic technique which involves the voluntary and precise obstruction, temporary or permanent, performed at the end of diagnostic studies or therapeutic studies on one or several branches of the pulmonary artery. The diagnostic indications are touched on briefly at the end of this review because they are older and better known than the therapeutic indications. The latter has developed in less than 10 years and concerns first and foremost two pathologies: hemoptysis and arterio-venous aneurysms of the lung. The erosive pseudo-aneurysm of the pulmonary artery complicating parenchymatous necrosis above all of infections or tumours should be sought in certain situations and treated by vascular occlusion. The pulmonary arteriovenous aneurysms may equally be treated by selective obstruction of their afferent pedicles by metal spirals or detachable balls. This technique, in sacrificing the minimum of pulmonary parenchyma, should be considered according to each case as a possible supplement or replacement for surgery.

Aneurysm↗
PubMed1988

Type II alveolar epithelial cell in vitro culture in aerobiosis.

A method of Type II alveolar epithelial cell culture in aerobiosis has been developed. Isolation of Type II cells was performed by digesting guinea-pig lung tissue with crude trypsin and elastase and using discontinuous Percoll density gradients. The Type II cells, as identified by light and electron microscopy, were cultured in aerobiosis for up to six days, in direct contact with the atmosphere in conditions mimicking those present in the lower respiratory tract. Significant activities of cellular superoxide dismutase (SOD), manganese dependent superoxide dismutase (Mn-SOD), catalase and glutathione peroxidase (GSH-Px) were found at the time of isolation. In contrast, cell glutathione content varied widely from one experiment to another. Changes of antioxidant enzymes were evaluated during cell culture in aerobiosis. SOD, Mn-SOD and catalase were significantly decreased after three days but were not significantly different between a three day and six day culture. Antioxidant changes did not influence the cell culture. In marked contrast, decrease in cell glutathione was associated with rapid cell death, whereas good cell survival was obtained at high levels of cell glutathione. Cell culture in aerobiosis will permit a precise evaluation of the effects of gases, particularly oxidant gases, on a primary culture of Type II alveolar epithelial cells.

Anaerobiosis↗
PubMed1988

Lymphocyte-mediated regulation of platelet activation during desensitization in patients with hymenoptera venom hypersensitivity.

T cells from peripheral blood of hymenoptera sensitive patients were studied before and after venom desensitization. Before treatment, T cells showed a variable but higher proliferative response to allergen than T cells of treated patients or controls. While before desensitization, T cell products, specifically released after in vitro allergen stimulation, were able to amplify the IgE-dependent platelet activity, we showed that after treatment of the same patients, T cell products strongly reduced platelet activation. Considering the modifications in platelet activation previously observed in patients treated by specific immunotherapy, the present results suggest that, through a modification of T cell reactivity to allergen, T cell functions are modulated by desensitization, and emphasize the involvement of T cell products in the desensitization mechanisms.

Adolescent↗
PubMed1988

[Invasive pulmonary aspergillosis].

Invasive pulmonary aspergillosis is an opportunistic pneumonia which is particularly common in immuno-depressed subjects. The most frequent risk factors are the intensity and duration of leucopaenia, cytotoxic drugs and steroid therapy. In the respiratory tract, the proliferation of Aspergillus fumigatus becomes possible when there is a failure of the reticulo-endothelial system and of the polymorphonuclear leucocytes. There is no typical clinical picture: one sees an acute febrile pneumonia resistant to antibiotics. However, the radiological signs are more suggestive with nodules and bilateral infiltrates with a tendency to cavity formation and sequestration. The prognosis is clinically linked to the rapidity of diagnosis. Broncho-alveolar lavage offers a new and non-invasive diagnostic method to search for Aspergillus mycelia or specific antigens. A direct examination and culture of sputum expectoration are both insensitive and non-specific but remain useful in some patients with leukaemia in a phase of agranulocytosis. Treatment rests on Amphotericin B taken orally.

Acute Disease↗
PubMed1988

[Lympho-epithelial thymoma. Anatomo-clinical and therapeutic study of 113 cases].

One hundred and thirteen cases of lympho-epithelial thymomas were studied retrospectively: 56 were of epithelial type, 20 of lymphocytic type, 30 were mixed and 7 were not defined. Eighty-eight were operated on (20 stages I, 47 stages II, 13 stages III and 8 stages IV). There were 69 primary resections (57 complete and 12 incomplete), followed by radiotherapy in 54 cases and 19 secondary resections after radiotherapy (10 complete and 19 incomplete). Twenty-five patients did not have an operation and were treated with radio- and chemotherapy. After primary resection the actuarial survival at 5 years was 64.07% and at 10 years 50.86%. After a secondary resection it was 43.74% at 5 years. After radiotherapy it was 18.67% at 5 years. In operated cases the prognostic importance of staging was confirmed. The cytological structure was not. In myasthenic cases the secondary respiratory complications worsened the prognosis. Post-operative radiotherapy seems to be justified in all cases, but its effect is not statistically significant when resection was complete. Those operated after radiotherapy only showed a benefit if the resection was complete. The outcome of metastatic disease in TLE has been under-estimated and seems to depend on local control of the tumour. The use of chemotherapy remains to be defined.

Adolescent↗
PubMed1988

Decrease of IgE-dependent platelet activation in Hymenoptera hypersensitivity after specific rush desensitization.

A receptor for the Fc fragment of IgE on human platelets has been recently described, which mediated an IgE-dependent activation in the presence of specific allergen. We investigated the allergen-induced activation of platelets from patients with Hymenoptera hypersensitivity before and after specific rush desensitization. Nineteen patients with a history of anaphylactic reactions were included (15 sensitive to yellow-jacket and four to honey-bee venom), fourteen/nineteen having experienced severe life-threatening systemic reactions and 5/19 large local reactions. All showed positive skin tests and high values of specific IgE. By comparison to the baseline results obtained before desensitization, a significant decrease of platelet activation (76.8% inhibition) after rush desensitization was observed. In the case of two polysensitized patients, after Hymenoptera venom desensitization alone, platelets not only lost their reactivity to venom but also towards the other allergen. This modulation of the IgE-dependent platelet reactivity during desensitization offers therefore a new approach for the study of allergen-induced desensitization.

Adolescent↗
PubMed1987

Subclinical lung inflammation in primary Sjögren's syndrome. Relationship between bronchoalveolar lavage cellular analysis findings and characteristics of the disease.

To directly evaluate whether a subclinical alveolar inflammation is associated with primary Sjögren's syndrome (SS), we evaluated the distribution of cells obtained by bronchoalveolar lavage (BAL) from the lower respiratory tract in 29 patients who had primary SS, but who were free of clinical pulmonary symptoms and had normal findings on chest roentgenograms. There was no difference in total cell counts of specimens from patients versus those of controls. An abnormal differential cell count was noted in 16 patients (55%). Two patterns of alveolitis were observed: a pure lymphocyte alveolitis (greater than 18% lymphocytes, present in 11 patients) and a neutrophil alveolitis (greater than 4% neutrophils, present in 5 patients). There was associated lymphocytosis in 4 of the patients with neutrophil alveolitis. All patients had normal results on pulmonary function tests. Patients with abnormal BAL findings showed clinical and biologic indexes of more severe disease than did those with normal BAL results, as demonstrated by greater extraglandular extension of the disease, higher mean values of serum gamma globulins and serum beta2-microglobulin, and higher prevalence of rheumatoid factor and of antinuclear antibody. Thus, our data demonstrate that BAL permitted the detection of subclinical inflammatory alveolitis in 55% of our patients with primary SS. A long-term followup is required to determine whether these patients will develop obvious pulmonary involvement.

Adult↗
PubMed1987

Alveolar macrophage dysfunction in systemic lupus erythematosus.

A high frequency of pulmonary infections has been a well-described feature of systemic lupus erythematosus (SLE). Alveolar macrophages (AM) play a crucial role in pulmonary bacterial defense. We therefore examined the antibacterial activity of AM and generation of superoxide anion in 17 patients with SLE without clinical or radiologic pulmonary changes and in 8 control subjects. Total cell count and cellular viability of AM (trypan blue exclusion) did not differ significantly between patients and control subjects. Antibacterial activity v/s Staphylococcus aureus was significantly decreased in both untreated and corticosteroid-treated patients (respectively, -16.2 +/- 7.4 and -42 +/- 12% compared with the normal value of 51 +/- 12%, p less than 0.001). The defect of antibacterial activity was observed as well v/s S. aureus as v/s Escherichia coli. In contrast, chemiluminescence response of AM before and after stimulation by either phorbol myristate acetate or opsonized zymosan did not differ among control subjects and treated and untreated patients with SLE. We did not find any correlation between disease activity and AM function. Antibacterial activity of normal AM was shown to be significantly reduced by previous incubation with SLE serum compared with normal human serum. Thus, our findings suggest that alteration of antibacterial activity of AM may contribute to the increased susceptibility to lung infections observed in SLE.

Adolescent↗
PubMed1987

Lymphocyte subpopulations in bronchoalveolar lavage in Sjögren's syndrome. Evidence for an expansion of cytotoxic/suppressor subset in patients with alveolar neutrophilia.

We initiated this study to determine the cellular composition and T-lymphocyte subpopulations of fluid from bronchoalveolar lavage from 15 patients with primary Sjögren's syndrome (1SS), six patients with secondary Sjögren's syndrome associated with primary biliary cirrhosis (2SS-PBC), eight patients with secondary Sjögren's syndrome associated with collagen-vascular diseases (2SS-CVD), and 12 normal subjects. All were nonsmokers who were free of clinical pulmonary symptoms and had normal findings on chest roentgenograms. Lymphocyte subsets were identified by mouse monoclonal antibodies that were specific for T-cells, helper/inducer, and suppressor/cytotoxic (namely, OKT3, OKT4, and OKT8). Patients with 1SS, patients with 2SS-PBC, and patients with 2SS-CVD had a significantly increased percentage of lymphocytes in fluid from bronchoalveolar lavage (respectively, 21.6 +/- 3.7 percent, 24.3 +/- 6.1 percent, and 25.6 +/- 3.9 percent) compared with the normal value of control subjects (9.9 +/- 1.5 percent). In addition, two of the 15 patients with 1SS and five of the eight patients with 2SS-CVD demonstrated an increased percentage of alveolar neutrophils. The predominant T-cell subset in patients with 1SS was T4+, and the mean T4:T8 ratio was normal. The percentage of T4+ cells was increased in patients with 2 SS-PBC, resulting in an increased T4:T8 ratio. In contrast, patients with 2 SS-CVD demonstrated a markedly increased percentage of T8+ cells, reflected by a shift in the T4:T8 ratio which was inverted. Patients with Sjögren's syndrome and with neutrophilia on bronchoalveolar lavage had a marked expansion of the T8+ lymphocyte subpopulation, where as patients with Sjögren's syndrome and with pure lymphocytosis on bronchoalveolar lavage showed predominantly T4+ cells. In addition, we found a strong positive correlation between the number of neutrophils and the number of T8+ cells in bronchoalveolar lavage from patients with Sjögren's syndrome (r = 0.74; p less than 0.05). Until the functional activities of OKT4+ and OKT8+ cells are better defined, the role that these cells play in the pathogenesis of pulmonary disease in Sjögren's syndrome remains unclear.

Adult↗
PubMed1987

[Alveolar macrophages and antibiotics. Review].

Although alveolar macrophages play a key role in pulmonary defence against infections, little is known about interactions of these cells with antibiotics. In vitro, some drugs fail to enter alveolar macrophages readily; in contrast, other antimicrobial agents (clindamycin, erythromycin, ethambutol) are highly concentrated by these cells, as well as josamycin, erythromycin and spiramycin in vivo. Moreover, clindamycin, erythromycin, chloramphenicol, rifampin and pefloxacin lead to an increased phagocytosis by alveolar macrophages, either by compromising bacterial antiphagocytic components or stimulating proper phagocytic activity of the cell. The influence of antibiotics upon mechanisms of microorganisms destruction (production of oxygen metabolites, oxygen independent system), upon regulation of lymphocyte functions (interleukin 1, prostaglandin E2) or other secretory activities (enzymes, modulators of cell activities, various bioactive products) have not been extensively studied and require further investigations.

Animals↗
PubMed1986

Release of superoxide anion by alveolar macrophages in pulmonary sarcoidosis.

Biological mechanisms involving nonprotease factors mediate the alterations of the alveolar structures which lead to the interstitial fibrosis of pulmonary sarcoidosis. Thus, we have investigated the production of oxidant species by BAL cells from 50 sarcoidosis patients and 18 healthy controls using a lucigenin-dependent CL method. Spontaneous and PMA-induced CL's were significantly higher in untreated patients and treated patients than in spontaneously cured patients or healthy controls (p less than .05). SOD inhibits 60 to 75% of spontaneous CL and 91 to 93% of PMA-induced CL. There was no apparent correlation between the CL of AM's and the radiological types, SACE levels, and gallium scans. In marked contrast, CL was significantly higher in patients with increased alveolar lymphocytosis (greater than or equal to 18%) than in patients with normal BAL. Since there were neither neutrophils nor eosinophils in BAL and since lymphocytes do not produce lucigenin-dependent CL, we believe that CL is produced by AM's. CL inhibition by SOD suggests that superoxide anion is involved in the production of CL. The release of both superoxide anion and related radicals may be of importance in the pathogenesis of pulmonary sarcoidosis.

Adult↗