Asymmetries in core-collapse supernovae from maps of radioactive 44Ti in Cassiopeia A.

Asymmetry is required by most numerical simulations of stellar core-collapse explosions, but the form it takes differs significantly among models. The spatial distribution of radioactive (44)Ti, synthesized in an exploding star near the boundary between material falling back onto the collapsing core and that ejected into the surrounding medium, directly probes the explosion asymmetries. Cassiopeia A is a young, nearby, core-collapse remnant from which (44)Ti emission has previously been detected but not imaged. Asymmetries in the explosion have been indirectly inferred from a high ratio of observed (44)Ti emission to estimated (56)Ni emission, from optical light echoes, and from jet-like features seen in the X-ray and optical ejecta. Here we report spatial maps and spectral properties of the (44)Ti in Cassiopeia A. This may explain the unexpected lack of correlation between the (44)Ti and iron X-ray emission, the latter being visible only in shock-heated material. The observed spatial distribution rules out symmetric explosions even with a high level of convective mixing, as well as highly asymmetric bipolar explosions resulting from a fast-rotating progenitor. Instead, these observations provide strong evidence for the development of low-mode convective instabilities in core-collapse supernovae.

Supernovae. 44Ti gamma-ray emission lines from SN1987A reveal an asymmetric explosion.

In core-collapse supernovae, titanium-44 ((44)Ti) is produced in the innermost ejecta, in the layer of material directly on top of the newly formed compact object. As such, it provides a direct probe of the supernova engine. Observations of supernova 1987A (SN1987A) have resolved the 67.87- and 78.32-kilo-electron volt emission lines from decay of (44)Ti produced in the supernova explosion. These lines are narrow and redshifted with a Doppler velocity of ~700 kilometers per second, direct evidence of large-scale asymmetry in the explosion.

Salivary PAF in acute myocardial infarction and angina: changes during hospital treatment and relationship to cardiac enzymes.

Salivary levels of platelet activating factor (PAF) were measured together with serum CPK and interleukin 2 receptor in 30 patients admitted to the coronary care unit, 9 patients with pulmonary tuberculosis, 10 with acute severe asthma and 8 normal controls. 16 of the 30 C.C.U. patients had sustained a acute myocardial infarction (M.I.) 5 had acute angina and the remaining 9 had non cardiac chest pain. Salivary PAF on admission was significantly higher in the M.I. Patients than in the normal subjects, asthmatics, tuberculosis patients and those with non cardiac chest pain (p < 0.001 in all cases) but not those with angina. After 48 hours PAF levels fell in the subjects with M.I. (p < 0.01) and no significant difference was seen between any group. PAF levels did not show any relationship with CPK levels or site of infarct in the M.I. patients. Interleukin 2 receptor was not significantly raised in the M.I. group as a whole but some individual patients showed markedly increased serum levels, but these levels did not correlate with either salivary PAF or serum CPK.

Testosterone levels during systemic and inhaled corticosteroid therapy.

Testosterone has importance both as a sex hormone and as an anabolic steroid promoting bone formation. Osteoporosis is associated with both hypogonadism and corticosteroid therapy. Testosterone levels are reduced by long term prednisolone treatment. Although high dose inhaled corticosteroid therapy may cause a variety of systemic effects including adrenal suppression, dermal thinning and a reduction in total bone calcium, its effect on testosterone levels is not known. Testosterone, luteinizing hormone, follicle stimulating hormone and sex hormone binding globulin were therefore measured in 35 male patients with respiratory disease attending an outpatient clinic (median age 58, range 21-75 years). They were grouped according to steroid therapy and compared with 19 age matched controls. Mean (SD) testosterone levels were 33% lower in 12 men on long term oral prednisolone [14.5 (6.0) nmol 1-1] than in controls [21.7 (6.3) nmol 1-1], but were not significantly reduced in 10 patients on low dose inhaled beclomethasone [200-800 micrograms day-1: 19.7 (3.7)] nor in 13 men taking high dose inhaled beclomethasone [1500-2,250 micrograms day-1: 17.9 (5.6)]. Levels of luteinizing hormone, follicle stimulating hormone and sex hormone binding globulin were similar in all four groups. These cross sectional data confirm that long term systemic corticosteroid therapy reduces testosterone levels. However, testosterone was reduced by only 18% (NS) by long term inhaled corticosteroids. Other mechanisms to explain the disordered bone metabolism should now be explored.

Diffuse pulmonary fibrosis and the Hermansky-Pudlak syndrome: clinical course and postmortem findings.

The Hermansky-Pudlak syndrome consists of albinism, platelet function defect, pigment laden macrophases and, on occasions, pulmonary fibrosis. The clinical course and postmortem findings of a patient with pulmonary fibrosis which mimicked cryptogenic fibrosing alveolitis are reported. Histological examination revealed a chronic inflammatory infiltrate of pigment laden microphages.

Down regulation in hypersensitivity pneumonitis.

Levels of soluble interleukin-2 receptor (sol-IL-2R) in the bronchoalveolar lavage fluid (BALF) of pigeon breeders with hypersensitivity pneumonitis were compared with BALF levels in asymptomatic pigeon breeders who had been exposed to pigeon allergens for an equivalent length of time. No mean difference in sol-IL-2R levels was detected when these levels were expressed per milliliter BALF, epithelial lining fluid, or per T-lymphocyte. In sarcoidosis, the availability of sol-IL-2R per T cell was significantly higher for the group with inactive sarcoidosis compared with the group with active sarcoidosis. The results do not support the hypothesis that down regulation, in subjects exposed to allergens causing hypersensitivity pneumonitis, is a function of cell-free sol-IL-2R levels in BALF. In the dynamic situation, however, the hypothesis appears tenable.

Immunoregulatory proteins in bronchoalveolar lavage fluid. A comparative analysis of pigeon breeders' disease, sarcoidosis and idiopathic pulmonary fibrosis.

Bronchoalveolar lavage fluid (BALF) cell profiles, interleukins 1 and 2, (IL-1 and IL-2) and soluble interleukin 2 receptor (IL-2R) levels from patients with pigeon breeders' disease (PBD) (n = 24) and asymptomatic pigeon breeders (n = 10) were compared with those from patients with active sarcoidosis (n = 11), inactive sarcoidosis (n = 10), idiopathic pulmonary fibrosis (n = 25) and normal subjects (n = 10). BALF total cells, lymphocytes and OKT4 receptor-bearing lymphocytes/ml were higher in PBD and active sarcoidosis compared with normals (P less than 0.02 all comparisons). In the asymptomatic pigeon breeders bronchoalveolar (BA) lymphocyte numbers/ml were higher than controls (P less than 0.01) producing a subclinical lymphocytic "alveolitis" in 80% of subjects, although compared with symptomatics, % OKT4 (helper) cell numbers were lower (P less than 0.05). OKT4/OKT8 ratios in both groups were normal, whereas in active sarcoidosis ratios were higher (P less than 0.05) but with considerable overlap. Mean levels of IL-1 and IL-2 were raised in the BALF from all groups compared with normals (P less than 0.01 all comparisons), IL-2 being higher in active sarcoidosis and IPF compared with PBD (P less than 0.01). There was no significant difference in detectable BALF soluble IL-2R between patient groups, although its levels correlated positively with IL-1 (22 paired samples from all groups (rs = 0.8, P less than 0.02) and negatively with % and T-lymphocytes/ml in PBD (rs = 0.75, P less than 0.02, rs less than 0.8, P less than 0.01). However, when BALF soluble IL-2R is expressed in terms of T lymphocytes/ml of epithelial lining fluid (ELF), asymptomatic pigeon breeders had significantly higher levels than their symptomatic counterparts (P less than 0.01). It is concluded that percentage lymphocytes [corrected] are similar in both groups of pigeon breeders, although those with PBD had increased numbers of OKT4 (helper) cells. Patients with active sarcoidosis could not be reliably differentiated from those with acute PBD on the basis of BAL cell profiles. Our results suggest that IL-1 leads to soluble IL-2R formation and that continued antigenic stimulation, as with inhaled pigeon allergens, results in a down regulation of BALF IL-2. Excess BALF soluble IL-2R on a cellular basis suggests a mechanism by which some pigeon breeders remain asymptomatic.

Immunoglobulin and antibody levels in bronchoalveolar lavage fluid from symptomatic and asymptomatic pigeon breeders.

Twenty-one symptomatic subjects with pigeon breeders' lung (PBL) and 10 asymptomatic pigeon breeders, with a similar exposure to pigeon antigens, underwent bronchoalveolar lavage. Total IgG, IgM and IgA in lavage fluid were determined as were specific antibody levels against antigens in pigeon serum and droppings. Results were converted to levels in epithelial lining fluid (ELF) using lavage and serum urea ratios. It was found that symptomatics represent a group that is hyperreactive to pigeon antigens compared with the asymptomatic group with significantly higher IgG, IgM, IgA levels as well as specific antibody levels against pigeon serum and droppings. Paired serum and ELF samples from 12 symptomatic subjects showed significantly elevated IgG, IgM and IgA levels in ELF compared with serum when values were expressed in terms of albumin. This strongly supports the concept of local production of immunoglobulins within the lung after inhaling immunogens as opposed to their diffusion from the vasculature. Results for IgA indicate that any putative protective role for this immunoglobulin is not valid in relation to the prevention of extrinsic allergic alveolitis. Analysis of smoking habits, lung immunoglobulins and response to inhalation challenge confirm the negative influence of smoking on total and functional lung immunoglobulins; however, levels in the ELF of ex-smokers suggest that the effect of smoking is not permanent. Smoking did not prevent responses to inhalation challenge.

Massive pleural effusion: an unusual presentation of Castleman's disease.

Giant lymph node hyperplasia (Castleman's Disease) is a rare cause of pleural effusion. We report the case of a 51 yr old West Indian male, who presented with a recurrent massive pleural effusion, due to a tumour arising from the pleura. He underwent parietal pleurectomy and subtotal excision of the tumour. Histological analysis of the specimen showed the features of multicentric Castleman's disease. Nine months following surgery he remains well, with no recurrence of the effusion.

Inhalation challenge in pigeon breeder's disease: BAL fluid changes after 6 hours.

The purpose of this study was to determine the cellular events occurring 6 h after bronchial inhalation challenge, in a group of pigeon breeders. Twelve subjects agreed to undergo challenge, either with nebulized pigeon serum (Ps) (n = 10), or with saline (n = 2). The development of characteristic symptoms was used to detect a positive response in combination with monitoring tests (white blood cell count (WBC), body temperature, and spirometry). An initial bronchoalveolar lavage (BAL) was performed before inhalation challenge, and a further BAL on the previously spared right middle lobe subsegment or lingula 6 h after challenge. Paired bronchoalveolar lavage fluid (BALF) samples were analysed for urea, albumin, total and differential WBC, interleukin-1 and interleukin-2. There was a significant increase in total cells, lymphocytes, T-lymphocytes, and neutrophils; numbers.ml-1 of BALF in responders. A monitoring score reflecting severity of patient response correlated with an increase in all cell types (p < 0.05). In conclusion, responders developed both a BALF lymphocytic and neutrophilic "alveolitis" following inhalation challenge, the degree of BALF "alveolitis" correlating with the severity of patient response.

A comparison of albumin and urea as reference markers in bronchoalveolar lavage fluid from patients with interstitial lung disease.

Lavage fluids were investigated for 67 subjects in 6 groups: 12 with active sarcoidosis, 8 with inactive sarcoidosis, 17 with pigeon breeder's disease, 10 asymptomatic pigeon breeders, 12 with idiopathic pulmonary fibrosis (IPF) and 8 normal subjects. Albumin and urea per ml of bronchoalveolar lavage fluid (BALF) were determined for each subject together with percentage return of fluid (BAL%). Novel assay systems were employed to measure urea and albumin and these were compared with existing analytical techniques. When compared with the control group, we found that urea per ml of BALF was not statistically different for all other groups, except those with pigeon breeder's disease who had significantly raised levels. For albumin, however, three groups had significantly higher levels than the controls, namely those with active sarcoidosis, pigeon breeder's disease and IPF. BAL% return showed no significant differences for any group when compared with the controls. We conclude that since albumin is significantly raised in most patients with interstitial lung disease it does not represent a suitable marker for the quantitation of reactive proteins in BALF. Urea shows much less variability between groups than does albumin, and hence in the absence of a proven alternative represents the most reliable estimate available of epithelial lining fluid dilution during the lavage procedure, providing dwell time is kept to a minimum.

Tuberculin testing: comparison of imotest with Heaf and Mantoux.

Immunisation against tuberculosis is still recommended for secondary school children in the UK. Only children who do not react to tuberculin tests are offered vaccination. We report the results of two studies, carried out to evaluate a new applicator of the disposable Imotest multiple puncture tuberculin test. The results demonstrate that Imotest is well tolerated and compares favourably with the Heaf and Mantoux tests. Imotest detected significantly more tuberculin responders than Heaf.

Measurement of interleukin-6 in bronchoalveolar lavage fluid by radioimmunoassay: differences between patients with interstitial lung disease and control subjects.

Bronchoalveolar lavage fluid (BALF) from subjects with a variety of interstitial lung diseases (active sarcoidosis, pigeon breeders' disease (PBD), asymptomatic pigeon breeders, patients with idiopathic pulmonary fibrosis) and from control subjects were assayed for interleukin-6 (IL-6) using a novel radioimmunoassay system. IL-6 was detectable in BALF from all groups, with disease groups showing significantly increased IL-6 levels compared with controls (P less than 0.01 in all cases). When these results were standardized, using urea to compensate for dilution effects in the BALF, only the asymptomatic pigeon breeders had significantly higher IL-6 levels than the controls (P less than 0.025), with all other groups showing no difference. When albumin was used for standardization, both the PBD group (P less than 0.001) and the sarcoidosis patients (P less than 0.01) had considerably lower levels of IL-6 than the control subjects. Using either albumin or urea for standardization, the PBD patients had significantly lower levels of IL-6 than do their asymptomatic counterparts (P less than 0.001 in both cases). This is contrasted by the finding of greatly elevated levels of IgG in the BALF of the PBD patients compared with asymptomatics (P less than 0.001). There was, however, no relation between IL-6 and IgG in any patient group, although the PBD patients had the lowest IL-6 and highest IgG as a group. These findings may suggest a mechanism by which asymptomatic subjects remain free from clinical complaints.