SO2-induced bronchopathy decreases airway sensitization with intratracheal ovalbumin in the rat.

We investigated in this study the effect of SO2-induced bronchopathy on airway sensitization to ovalbumin in the rat. Sprague-Dawley rats were immunized with a single intratracheal injection of ovalbumin (OA) 100 micrograms in 0.1 ml PBS or 0.1 ml Bordetella pertussis (BP) heat-killed vaccine (6.5 X 10(9) cells X ml-1). The rats were primed immediately after SO2 exposure (60 h, 200 ppm; group I, n = 16) and three months after exposure was achieved (group II, n = 24), then compared to a control group exposed to air (group III, n = 30). Airway sensitization was evaluated by the in vitro contractile response to antigen challenge using paired tracheal rings. Specific IgE level was determined with PCA reactions. No significant difference was found in the maximal contractile responses to carbamyl choline within and between each group. Excepted in animals of group III, OA alone was not found able to sensitize the airways. When OA was used in association with BP, sensitization of the airways occurred, but this occurrence was found to depend upon a previous SO2 exposure: 73.3% in group III, 41.7% in group II and 25% in group I were sensitized. In addition, only five animals (BP + OA injected rats of group III) displayed a PCA positive reaction. It is concluded that: 1) the concomitant intratracheal injection of BP with OA increased the occurrence of specific airway sensitization, 2) a previous chronic exposure to SO2 decreased the specific tracheal smooth muscle sensitization to intratracheal ovalbumin. This decrease persisted, although slighter, when immunization was done three months after the exposure to SO2 was stopped.

[Retrospective study of 77 cases of purulent pleurisy]. / Etude rétrospective de 77 cas de pleurésies purulentes.

77 cases of non-tuberculous empyema were studied retrospectively. The data of past history, laboratory, radiological, bacteriological and outcome were gathered. The mean delay between initial symptoms and clinical diagnosis was 2.6 weeks in this study. It was longer for those anaerobic features (p less than 0.02) whose details were unravelled. "Blind" antibiotic therapy before the first pleural aspirate is still common (46.7% of cases) and did not alter the frequency with which the causal bacteria was found, nor the distribution of the bacterial population. Pleural aspirate enabled the germ or germs responsible to be identified in 63% of cases. Streptococcus pneumoniae (n = 15) and anaerobic bacterias (n = 26) infections were predominant. Early pleural drainage in a trained unit care is the essential element in the treatment in association with appropriate antibiotics and prolonged physiotherapy. This triple therapy approach leads to a medical cure in practically all the patients and avoids a recourse to surgery.

Suppression of bronchoalveolar lymphocyte antibody secretion by alveolar macrophage: an in vitro study in the rabbit.

The effect of rabbit alveolar macrophage (AM) on the antibody secretion of bronchoalveolar lymphocytes was investigated in vitro, using a plaque-forming cell assay. Animals were intratracheally primed and reimmunized with 10(10) sheep red blood cells (SRBC). Free alveolar cells were obtained by lung lavage and broncho-alveolar lymphocyte-enrichment was achieved through Sephadex G-10 columns. Cell suspensions with various macrophage-to-lymphocyte ratios (AM:L from 1:25 to 3:1) were prepared using appropriate numbers of plastic adherent alveolar cells. After a 4 day in vitro co-culture of 5 X 10(6) alveolar cells (AM plus lymphocytes) with 3 X 10(6) SRBC, IgM and IgG antibody-forming cells (AFC) were counted. A significant suppressive effect (p less than 0.05) of AM on both IgM and IgG-AFC was observed when AM:L ratio was increased from 1:25 to 1:10. This effect was slightly accentuated with higher AM:L values, required viable AM, and was not affected by adding indomethacin in the culture medium. Moreover, a preliminary co-culture of AM with bronchoalveolar lymphocytes and the antigen was necessary for the expression of this suppressive effect. These data suggest that the suppressive activity of primed AM on alveolar lymphocytes may be of physiologic significance in vivo in the regulation of one of the pulmonary immune responses to airborne antigens, namely local antibody production.

[Atelectasis caused by lung folding]. / L'atélectasie par enroulement.

An atypical disturbance of ventilation supervening a pleural effusion may occur due to atelectasis by lung folding which is seen radiologically as a round image close to the chest wall with the appearance of a pseudo-tumour. The authors review the mechanisms and the clinical and radiological presentation of this disorder based on 7 cases and a review of the literature. The posterior basal type with adhesions to the chest wall are the most frequent. An intra-parenchymatous and a double-form are described. The diagnosis of this benign disorder is radiological. It is based on a characteristic displacement of the vessels and bronchi and associated pleural signs. Recognition of these signs avoids all invasive procedures.

Immunologic competence of the bronchi in the rabbit: the IgA-mediated plaque-forming response to intratracheally injected sheep erythrocytes.

Immune responses to intratracheally injected sheep erythrocytes in rabbits were investigated in bronchi, thoracic lymph nodes (TLN), mesenteric lymph nodes (MLN) and spleen using an IgA-mediated haemolytic plaque-assay. The time-course appearance of specific IgA antibody forming cells (IgA-AFC) was studied in each tissue after primary and secondary immunizations. Overall low splenic and MLN responses suggest weak systemic and intestinal immunizations, respectively. Peak IgA-AFC concentrations occurred in TLN five days after priming and, in a lesser extent, three days after the booster. Conversely, the bronchial response was delayed, progressive and enhanced by the re-immunization. These results strongly suggest that bronchial-derived, IgA-precommitted cells are the major source of these specific IgA-AFC which concentrate in bronchi and that, before homing in the submucosa, they accumulate transiently in the TLN.

[Bacteriology of bronchial secretions. Proposals for a practical attitude in bacterial respiratory tract infections]. / Bactériologie des sécrétions bronchiques. Propositions pour une attitude pratique dans les infections bactériennes respiratoires.

The inadequacy of the standard bacteriological method in the study of expectorations is unanimously accepted. Oropharyngeal contamination of specimens largely explains why this examination is a poor index of the causative organisms in bacterial respiratory infections. In a mixed clinical situation with few or non-specific signs of bacterial infection and of variable severity, the physician should answer two questions: 1) Is it a bacterial infection? 2) What is the causative organism? and their corollary: 1) Should one prescribe an antibiotic? 2) Which one? Only culture of blood or pleural fluid allow an accurate reply to these questions in about 50% of cases and they are the indispensable investigations of reference. Initial efforts undertaken to improve the standard examination of expectorations never overcome the stumbling block of oro-pharyngeal contaminations. The bacterial count of expectorated bacteria, a non traumatic method, represents some real progress. In 50% of cases it enables a predominant pathogen to be identified before any antibiotics are given. Bronchoscopy diminishes contamination, allows direct sampling and the inspection and biopsying of bronchial mucosal lesions and aids drainage in very suppurative disorders. Trans-tracheal puncture avoids oropharyngeal contamination in the majority of cases and appears to provide reliable results much more often. A pragmatic approach is recommended according to the clinical picture. Bronchial and limited alveolar infections which are well tolerated, heal without exception on blind antibiotic therapy. In suppurating infections (bronchiectasis, cavitating pneumonias), the yield and the reliability of the examinations are increased. Serious bacterial infections, by their extent or by their site, justify a more aggressive diagnostic and therapeutic attitude. It should be stressed, however, that death caused by inadequate antibiotic therapy remains the exception when one or two successive courses of antibiotics have been prescribed for the pathogens presumed responsible according to the clinical picture or found after one or more bacterial examinations.

[Experimental animal pathology. Immuno-allergic asthma (author's transl)]. / Les asthmes immuno-allergiques. Pathologie expérimentale animale.

One of the interests of experimental animal work is the power to analyse a given pathophysiological mechanism and also the privilege of witnessing its appearance. Immuno-allergic asthma, mediated by specific IgE of an allergen only represents one aetiological form, among many others, that make up the clinical spectrum of asthma in the human species. It is, however, the type of asthma whose experimental reproduction, a priori, is the most easily reproduced and has been the most tested. The different protocols used an analysis of the results and the lines of current or projected research form the object of this review.

Effects of the administration of O2 on ventilation and blood gases in patients with chronic obstructive pulmonary disease during acute respiratory failure.

The effects of the administration of 100% oxygen on minute ventilation (VE) and arterial blood gases were studied in patients with chronic obstructive pulmonary disease during acute respiratory failure. The administration of O2 resulted in an early decrease in VE, which averaged 18% +/- 2 SE of the control VE, and was due to a decrease in both tidal volume (VT) and respiratory frequency (f). This was followed by a slow increase in VE, such that after 15 min of breathing O2, VE rose to 93 +/- 6% of the control room air value, with both VT and f similar to control values. Despite the small difference between VE while breathing room air and that at the fifteenth minute of O2 inhalation, PaCO2 increased by 23 +/- 5 mmHg, and no significant correlation was found between the changes in VE and PaCO2. By the fifteenth minute of O2 inhalation the PaO2 averaged 225 +/- 23 mmHg, and it was concluded that despite the removal of the hypoxic stimulus of O2 inhalation, the activity of the respiratory muscles remained great enough to maintain VE at nearly the same degree as that while breathing room air. Consequently, the changes in PaCO2 after the administration of O2 were mainly due to increased inhomogeneity of VA/Q distribution within the lungs.

[Panlobular emphysema. Value of radiology to assess the need for surgery (author's transl)]. / Emphysème pan-lobulaire. Apport de la radiologie dans l'indication opératoire.

Surgical decompression in 12 patients with panlobular emphysema and severe respiratory insufficiency, over the last 5 years, gave encouraging postoperative results. Preoperative radiological examination results were well correlated with findings during operation. Signs of thoracic distention and diffuse peripheral hypovascularization were noted in all cases. Furthermore, at least on the affected side, all patients showed avascular zones presenting as large bullae or as bullous zones extending over at least half of the hemothorax region, and compression signs affecting the lung parenchyma, the mediastinum, and the diaphragm. Radiological investigation is essential for assessing the need for operation, as it remains the only method which can demonstrate the part played by the bullae and the rest of the parenchyma in the alteration of respiratory function. Data can be obtained by standard radiological examinations with dynamic films on forced inspiration and expiration, and by computed tomography. However, pulmonary angiography gives a more precise evaluation of the vascularization of the remaining parenchyma, which is important when choosing the side to be operated upon, or that which should be operated upon first in cases of bilateral symmetrical lesions.

SO2-induced bronchopathy in the rat: abnormal permeability of the bronchial epithelium in vivo and in vitro after anatomic recovery.

The effects of different SO2 exposures on the uptake and transport of exogenous proteins by the tracheobronchial epithelium were investigated in vivo and in vitro using explanted tissue from rat lungs. By optical and electron microscopy, modifications in ferritin uptake and transport were observed, depending on SO2 exposure and on subsequent structural changes; these changes involved a considerable increase in mucosal permeability, both in vivo and in vitro, affecting the epithelium of the trachea and main bronchi. Such an increase, although reduced, was observed 3 months after SO2 exposure had been discontinued, at a time when the structure appeared normal. These findings suggested that SO2-induced changes in upper respiratory epithelium may be responsible for long-term abnormal permeability and that such changes may contribute to the pathogenesis of chronic bronchopathy.

[Surgical treatment of bullae in diffuse emphysema (author's transl)]. / Traitement chirurgical des lésions bulleuses dans l'emphysène diffus.

The authors present short and medium-term results of bullae surgery in patients with severe panacinar emphysema. There were no deaths. Almost always (8/9) dramatic subjective and significant objective functional results are encouraging.

[Therapy of enlarging emphysematous bullae during acute respiratory failure (author's transl)]. / La thérapeutique des bulles d'emphysème au cours des poussées aiguës chez les insuffisants respiratoires.

The authors report results of transthoracic drainage of enlarging emphysematous bullae in patients with acute respiratory failure and chronic lung disease. In two cases, patients survived the acute failure. Respectively six months and one year later, bulla was smaller than before the failure and respiratory symptoms and function tests were improved.

[Extensive bronchial dystrophy. Physiopathology and treatment of suppurative complications (author's transl)]. / Les dystrophies bronchiques étendues. Physiopathologie et traitement des complications suppuratives.

Extensive bronchial dystrophy differs by its histopathology, course and treatment from chronic obstructive bronchitis. This dystrophy leads to cavities which are virtually constantly infected. The extension of infection to adjacent alveoli may be dramatic, contrasting with underlying slight chronic respiratory failure. The existence of these cavities explains the preponderant role in therapy of drainage and the fact that antibiotic therapy would appear to be indicated only in the case of extension of infection to the alveoli and the peribronchial tissues.

Experimental modifications induced by membrane oxygenators on lung ultrastructure in dogs and baboons.

Extracorporeal circulation with membrane oxygenator (E.C.M.O.) was performed in 6 dogs and 5 baboons during 4 to 57 hours. Examination of pulmonary samples showed progressive lesions in the two species: at the second hour of E.C., alteration of capillary endothelium, at the sixth, extensive lesions of all the lung structures, worsening later on. We discussed whether these lesions are related to the E.C.M.O., their reversibility and the questionable benefit of E.C.M.O. for management of respiratory distress syndrome.

[Surgical correction of tetralogy of Fallot with an iatrogenic obstruction on 1 branch of the pulmonary artery]. / Correction chirurgicale de la tétralogie de Fallot comportant un obstacle iatrogène sur une branche de l'artère pulmonaire.

The au;hors report 12 cases of Fallot' tetralogy with stenosis or obstruction of one of the two branches of the pulmonary artery following palliative anterior anastomosis. The complications of correction by open heart surgery include the frequent incidence of pulmonary hypertension, which was responsible for 4 deaths. No satisfactory explanation could be found for these poor results. It is desirable to avoid the creation of asymetry in pulmonary blood supply in Fallot's tetralogy and, if such should be found, suggestions are made for its correction by open heart surgery in order to improve the prognosis.