Papain-induced asthma: a man with dyspnea from dawn till dust.

A 52-year-old man, a current smoker (40 pack years) with unremarkable medical history, was referred to the outpatient pneumology clinic because of recent complaints of shortness of breath and wheezing, which were relieved by inhaled bronchodilators. Serial peak expiratory flow (PEF) measurements showed a clear rise in PEF during the weekend and a fall on the evening after the first day of the week. It also showed that evening values were always lower than morning values. During a holiday, a slow but persistent rise in PEF was observed. Such a pattern is highly suggestive for occupational asthma. A detailed description of his job revealed papain exposure. After a positive specific IgE and skin prick test for papain the diagnosis of papain induced asthma was made. When an allergy and serious lung function impairment is proven against products encountered in a work related situation, not improving after maximal preventive measures, the patient is advised to change job.

Effects of capric acid on rumen methanogenesis and biohydrogenation of linoleic and α-linolenic acid.

Capric acid (C10:0), a medium chain fatty acid, was evaluated for its anti-methanogenic activity and its potential to modify the rumen biohydrogenation of linoleic (C18:2n-6) and α-linolenic acids (C18:3n-3). A standard dairy concentrate (0.5 g), supplemented with sunflower oil (10 mg) and linseed oil (10 mg) and increasing doses of capric acid (0, 10, 20 and 30 mg), was incubated with mixed rumen contents and buffer (1 : 4 v/v) for 24 h. The methane inhibitory effect of capric acid was more pronounced at the highest (30 mg) dose compared to the medium (20 mg) (-85% v. -34%), whereas the lower dose (10 mg) did not reduce rumen methanogenesis. A 23% decrease in total short-chain fatty acid (SCFA) production was observed, accompanied by shifts towards increased butyrate at 20 mg and increased propionate at 30 mg of capric acid (P < 0.001). Capric acid linearly decreased the extent of biohydrogenation of C18:2n-6 and C18:3n-3, by up to 60% and 86%, respectively. This reduction was partially due to a lower extent of lipolysis when capric acid was supplemented. Capric acid at 20 and 30 mg completely inhibited the production of C18:0 (P < 0.001), resulting in an accumulation of biohydrogenation intermediates, mainly C18:1t10 + t11 and C18:2t11c15. In contrast to effects on rumen fermentation (methane production and proportions of SCFA), 30 mg of capric acid did not induce major changes in rumen biohydrogenation as compared to the medium (20 mg) dose. This study revealed the dual action of capric acid, being inhibitory to both methane production and biohydrogenation of C18:2n-6 and C18:3n-3.

Endoscopic management of severe subglottic stenosis in Wegener's granulomatosis.

The optimal treatment for severe subglottic stenosis secondary to Wegener's granulomatosis remains controversial. We report the case of a symptomatic middle-aged woman who was successfully treated with intratracheal dilation and intralesional injection of corticosteroids. The literature related to this issue is being reviewed.

Preoperative work-up of a solitary diaphragmatic mass in a patient with right shoulder pain: a case for diagnosis.

A patient presented with right shoulder pain. Imaging studies revealed an apparently solitary soft tissue pleural lesion, accompanied by a very small pleural effusion. On medical thoracoscopy, a diffuse malignant pleural mesothelioma was found. Thoracoscopy proved to play an essential part in the diagnostic work-up, avoiding a futile thoracotomy for a presumed solitary soft tissue tumour.

Effect of dietary protein, essential and non-essential amino acids on the performance and carcase composition of male broiler chickens.

1. The present study was conducted to determine the possibility of using low-protein broiler diets supplemented with synthetic amino acids. The effects on performance, carcase composition and nitrogen retention were evaluated. 2. A starter diet was given, ad libitum, from 7 to 21 and a finisher diet from 21 to 42 d of age. Body weight, weight gain, food intake and food conversion (FC) were determined at 3 and 6 weeks of age. Abdominal fat deposition (AFD), carcase yield, carcase fat and protein and nitrogen retention were determined at 6 weeks of age. During the starter period chicks were given a 231 g/kg crude protein (CP) diet and a low protein diet supplemented with synthetic amino acid, a: to National Research Council recommendations, b: to the concentration of the control diet, and c: in agreement with the pattern of body composition. Glutamic acid and glycine were added to some diets as sources of non-essential amino acids (NEAA). All diets contained 12.62 MJ metabolisable energy (AMEn)/kg. The diets administered between 3 and 6 weeks were comparable to the starter diets, except that they contained more AMEn (12.85 MJ/kg) and less protein. 3. Performance equal to that of high protein controls was obtained with birds fed a low protein diet supplemented with synthetic essential and NEAA to the amounts in the control diet or based on the amino acid profile of body protein. This was not achieved with low protein diets supplemented with synthetic amino acids to the amounts recommended by NRC. 4. Without altering performances, the efficiency of protein utilisation of birds fed on low protein diets was superior to that of birds fed on the commercial control diet and their nitrogen excretion was reduced by 26%. The percentage carcase yield and protein was unaffected by the dietary regimen but carcase fat content and AFD increased as the protein content of the diet decreased. 5. These results show that it is possible to obtain the same performances with low protein diets supplemented with synthetic amino acids, using an ideal amino acid balance. However, low protein diets result in a higher carcase fat content.

Relationship between axial motion and volume displacement of the diaphragm during VC maneuvers.

During semistatic inspiratory and expiratory vital capacity (VC) maneuvers, axial motion of the diaphragm was measured by lateral fluoroscopy and was compared with diaphragmatic volume displacement. Axial motion was measured at the anterior, middle, and posterior parts of the diaphragm, and the mean of these measurements was used. The volume displacement was calculated in two ways: first, from respiratory inductive plethysmograph-(Respitrace) derived cross-sectional area changes of rib cage and abdomen (Vdi,RIP) by means of a theoretical analysis described by Mead and Loring (J. Appl. Physiol. 53: 750-755, 1982) and, second, from fluoroscopically measured changes in position and anteroposterior surface of the diaphragm (Vdi,F). A very good linear relationship was found between Vdi,RIP and Vdi,F during inspiration as well as expiration (r greater than 0.95), indicating that the analysis of Mead and Loring was valid in the conditions of the present study. The diaphragmatic volume displacement (active or passive) accounted for 50-60% of VC. A very good linear relationship was also found between mean axial motion and volume displacement of the diaphragm measured with both methods during inspiration and expiration (r greater than 0.98). Our data suggest that, over the VC range, diaphragmatic displacement functionally can be represented by a pistonlike model, although topographically and anatomically it does not behave as a piston.

Effects of aminophylline on respiratory muscle interaction.

We studied the effects of aminophylline on respiratory muscle interaction during quiet breathing by measuring (1) changes in rib cage and abdominal cross-sectional area, (2) tidal volume, (3) abdominal and esophageal pressure, (4) diaphragm and parasternal intercostal electromyogram (EMG) and parasternal intercostal intramuscular pressure, and (5) triangularis sternl and transversus abdominis EMG, in 14 supine anesthetized dogs. Measurements were done before and 5 and 10 min after administration of progressively increasing doses of aminophylline, reaching a total dose of 5, 10, 20, 40, and 80 mg/kg. In 12 of 14 dogs after aminophylline administration, quiet inspiration became biphasic, or if inspiration was already biphasic under control conditions, the first phase was clearly enhanced after aminophylline administration. Biphasic inspiration was defined as an inspiratory pattern in which rib cage and abdominal expansion showed two distinct phases. First, the onset of inspiration was characterized by a sudden increase in rib cage cross-sectional area often associated with a decrease in abdominal dimensions. During this initial part the parasternals and the diaphragm were electrically silent, confirming that it was achieved by relaxation of expiratory muscles. Further inspiration occurred predominantly through expansion of the abdomen. In the first phase, a pressure drop in the parasternal intercostals was present, presumably due to passive shortening of these muscles caused by expiratory muscle relaxation. On the average, 42 +/- 28% of the rib cage expansion was due to expiratory muscle relaxation at a dose of 80 mg/kg versus 17 +/- 21% under control conditions (p less than 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)

Diaphragmatic displacement measured by fluoroscopy and derived by Respitrace.

In eight healthy volunteers we simultaneously measured the axial diaphragmatic motion by fluoroscopy and the cross-sectional area changes of the rib cage (RC) and abdomen (ABD) by Respitrace (RIP) during semistatic vital capacities (VC). We found that, if the fluoroscopic axial displacement of the posterior part of the diaphragm between residual volume (RV) and total lung capacity (TLC) is considered equal to 100%, the movement of the middle part is 90%, whereas that of the anterior part is only approximately 60%; the ratio of the axial displacements to mouth volume, furthermore, decreases at high lung volumes, especially for the anterior part. The RIP signal is nearly linearly related to mouth volume, but the contribution of the RC (delta RC) progressively increases (and is approximately 80% RIP at TLC), whereas the volume contribution of the ABD (delta ABD) levels off (to 20% RIP at TLC). The diaphragmatic volume displacement calculated from the theoretical analysis described by Mead and Loring also levels off at high volumes similarly as the ABD but is approximately 50% RIP at TLC. Finally, the axial movements of the three parts of the diaphragm are linearly related to the RC and ABD cross-sectional-area changes (r 0.91-0.97) and are even significantly better correlated with the "calculated" diaphragmatic volume displacement.

Effects of acute hyperinflation on the mechanical effectiveness of the parasternal intercostals.

We studied the mechanical effectiveness of the parasternal intercostals at FRC and near TLC in 14 supine, vagotomized, and anesthetized dogs. First, we determined the relationship between parasternal intramuscular pressure (Pps), measured with Gaeltec 12 CT-mini-transducers, and parasternal EMG activity (Eps) during breathing at FRC and near TLC. Second, we examined the changes in Pps and the changes in parasternal force (Fps) generated during bilateral parasternal stimulation at FRC and near TLC with a given supramaximal stimulus. Before phrenicotomy, the inspiratory increases in Pps remained relatively constant near TLC (FRC, 50.4 +/- 16.5 versus TLC, 48.7 +/- 13.3 cm H2O, NS), whereas the Eps clearly decreased (82.9 +/- 5.5% FRC, p less than 0.01). This indicates that the gain converting electrical activity into pressure for the parasternals is greater near TLC than at FRC. A similar pattern of changes in Pps and in Eps was observed during quiet inspiration at FRC and near TLC after phrenicotomy. During bilateral parasternal stimulation the increases in Pps near TLC tended to be greater than those at FRC (140.7 +/- 28.6 versus 100 +/- 28.3 cm H2O, NS), whereas the increases in Fps were significantly greater near TLC than at FRC (277.4 +/- 60.6 versus 214.2 +/- 47.1 g, p less than 0.05). Therefore, we conclude that the mechanical effectiveness of the parasternal contraction near TLC remains relatively unchanged and is even greater in relation to that at FRC.

The effect of breath size and posture on calibration of the respiratory inductive plethysmograph by multiple linear regression.

The accuracy of the respiratory inductive plethysmograph (Respitrace) for estimation of lung volume changes during quiet breathing and vital capacity (VC) manoeuvres was evaluated using a variant of the multiple linear regression (MLR) technique. We applied this technique successively on quiet breathing, on the whole VC, and on each of the four quarters of the VC separately. This was carried out in six body positions. The best estimation of tidal volumes was obtained when calibration factors calculated during quiet breathing were used. The best estimation of VC was obtained when the calibration factors were adapted to the level of lung inflation. These results indicate that, using a single position MLR calibration method, the Respitrace measures tidal and VC mouth volumes very accurately. The accuracy of this MLR method for estimation of the rib cage and abdominal contributions was validated by comparison with isovolume calibration factors. Both techniques gave very similar results during tidal breathing. However, the MLR calibration factors may have no physiological meaning (i.e. for volume partitioning) when they are calculated from VC manoeuvres, in which more than two degrees of freedom are involved.