Assessment of the respiratory compliance in awake subjects using pressure support

Pressure support (PS), a new mode of ventilatory assistance, is known to induce respiratory muscle relaxation. It was used to obtain reliable measurements of the compliance of the respiratory system (Crs) in awake subjects. PS was applied, through a mouthpiece, at four successive levels (0, 0.75, 1 and 1.25 kPa) to 30 healthy subjects. At the highest PS level, the subject's relaxation was obtained as assessed by a decrease in the occlusion pressure from 0.10 +/- 0.06 to 0.05 +/- 0.04 kPa, whereas the minute ventilation increased (from 7.5 +/- 1.5 to 13.8 +/- 3.3 l.min-1), and the end-tidal carbon dioxide tension (PCO2) decreased (from 5.0 +/- 0.4 to 3.2 +/- 0.5 kPa) below its apnoea threshold. In three subjects, respiratory muscle relaxation was confirmed by a fall in diaphragmatic electromyographic activity. Crs was calculated as the ratio of the tidal volume to the corresponding end-inspiratory airway pressure (i.e. PS level) since, at end inspiration, a zero-flow period was obtained. Crs was highly correlated (r = 0.77) to the height (Ht) of the subjects: Crs (l.kPa-1) = 3.56 x Ht (m) -4.86 (+/- 0.23), allowing normal values to be determined. In order to evaluate the applicability of the method to patients, Crs was measured in four patients with scoliosis, and was found to range from 45-82% of the predicted values. It is suggested that this simple method of Crs determination may be used to characterize various chest wall or pulmonary diseases.     

Highly purified omega-3-polyunsaturated fatty acids for topical treatment of psoriasis. Results of a double-blind, placebo-controlled multicentre study

We report the results of a multicentre, double-blind, placebo-controlled study of topical therapy with omega-3-polyunsaturated fatty acids (omega-3-PUFA) in 52 patients suffering from moderate plaque-type psoriasis. In each patient, two similar stable psoriatic plaques served as indicator lesions for the study. One indicator lesion was randomly assigned to treatment with topical preparations of highly purified omega-3-PUFA in one of two concentrations (1 or 10%), and the other was treated with placebo. Efficacy assessment was based on changes in local psoriasis severity index, area involved, erythema, desquamation, induration and pruritus. After 8 weeks of treatment, all indicator lesions had improved significantly, compared with baseline. However, no statistically or clinically relevant differences between the omega-3-PUFA-treated and the placebo-treated lesions were found. Therapy was well tolerated and, apart from one patient who developed perilesional eczema, no clinically relevant adverse events occurred. In conclusion, topical omega-3-PUFA were not effective in a randomized, placebo-controlled, double-blind setting. Results of non-blind trials should be (re-)considered with caution.     

Swenson's operation for neonatal Hirschsprung's disease

OBJECTIVE: To describe our experience with Swenson's operation for Hirschsprung's disease done during the neonatal period. DESIGN: Retrospective study. SETTING: University department of paediatric surgery. SUBJECTS: 10 Neonates with Hirschsprung's disease. INTERVENTIONS: Rectosigmoidectomy and pull through (Swenson's operation), with covering transverse colostomy. MAIN OUTCOME MEASURES: Mortality, morbidity, and continence. RESULTS: The median age at definitive operation was 25 days (range 15-35). There was one late death three weeks after discharge from hospital of respiratory and cardiac failure. Two patients presented with caecal perforation and two with intestinal obstruction; in all four Hirschsprung's disease was diagnosed on frozen section, a transverse colostomy was done, and the Swenson's operation was done electively. The other six were diagnosed by barium enema examination and biopsy, and underwent total bowel irrigation followed by Swenson's operation and transverse colostomy. The colostomies were closed three to four weeks later. There were no postoperative complications. All nine surviving patients were continent (3-4 stools/day), at a mean (SD) follow up of 21 (5) months. CONCLUSION: With the current high standards of anaesthesia and neonatal intensive care, and an experienced surgeon, Swenson's operation for neonatal Hirschsprung's disease is safe and the procedure of choice for this condition.     

Respiratory symptoms and bronchial responsiveness are related to dietary salt intake and urinary potassium excretion in male children

Six men were accidentally exposed to NO2 when they were changing a propeller using a gas burner in the poorly ventilated hold of a ship. All of them were admitted to hospital with shortness of breath and cough. Chest X-ray on admission revealed diffuse, patchy and infiltrative shadows, leading to the diagnosis of pulmonary edema in all five patients. Steroid therapy was effective and followed by a quick recovery in all patients. None developed third phase manifestations characterized pathologically by bronchiolitis obliterans.     

Models of high velocity impact phenomena

Models of craters formed by impacts at velocities of up to 24.5 km/sec have been computed using the Smooth Particle Hydrodynamics, MESA, EPIC and CALE codes. These modeling efforts are compared to data obtained from the Hypervelocity Microparticle Impact project at Los Alamos using the van de Graaff accelerator. A factor of 5 increase in yield strength was needed to account for high strain rate effects and to match the data. Structure in the data is addressed by using crater volume instead of crater diameter cubed. Detailed code comparisons were made between the four codes with good agreement found.     

The neu-oncogene product in serum and tissue of patients with breast carcinoma

Patients with non-cardiac chest pain (NCCP) (n = 387) and cardiac chest pain (CCP) (n = 93) were compared with community controls (n = 81), using a symptom questionnaire that assessed the presence of irritable bowel syndrome (IBS), functional dyspepsia, and oesophageal dysfunction and chest pain characteristics. A significantly (p < 0.05) increased prevalence of symptoms compatible with IBS occurred in NCCP patients when compared with those with CCP and with controls. Dysphagia was more frequent in both those with non-cardiac and cardiac chest pain than in controls; this was not apparent, however, when patients with concomitant IBS were excluded. The presence of oesophageal or gastrointestinal symptoms did not enable discrimination with regard to the chest pain characteristics. We conclude that unselected referred patients with documented NCCP are more likely to have IBS and that the presence of oesophageal symptoms such as dysphagia may merely reflect the spectrum of the 'irritable gut'.     

THE INFLUENCE OF LOAD MISALIGNMENT DURING UNIAXIAL LOW-CYCLE FATIGUE TESTING—II: APPLICATIONS

Abstract— Models for predicting scatter bands due to bending have been applied to four alloys, namely AISI 316L, Nimonic 101, 9 Cr-1 Mo, and IN 718. The alloys were tested extensively by 26 laboratories in an international round robin exercise sponsored by the Community Bureau of Reference (BCR) of the EC. After initially selecting data for analysis on the basis of their confirmed conformance to the ASTM bending criterion, it has been shown that in all four materials a major fraction of the data scatter could be attributed to bending. Furthermore, at the lowest strain range the predicted bending component represents the highest proportion of the experimental interlaboratory scatter. Many laboratories did not report any measure of bending and so could not be used in the initial analysis. However, a further interesting deduction from the models is that the entire BCR data-set can be encompassed within a scatter band based upon a bending criterion that is twice the allowable ASTM limit. Differences in the extent of scatter between materials at a given total strain range can be attributed to the gradient of the logarithmic plot of total strain range as a function of lifetime.