Effect of ipratropium bromide on repeated methacholine challenges.

The purpose of this study was to trace the protective effect of ipratropium bromide (IB) during methacholine inhalation challenge (MIC) at the first and fourth hour after its administration. IB-inhaler contains 0.02 mg IB in each puff and it was used in the usual dosage of two puffs (0.04 mg). In 20 asthmatic patients, the dose of methacholine caused a drop in FEV1 of 20% (PD20-FEV1). It was concluded that IB protected patients significantly one hour after its administration and showed a significant bronchodilating effect in comparison to placebo. IB protected 19 of the 20 patients one hour after administration during MIC while placebo protected none. IB protected 13 of the 20 patients, after the second PD20-FEV1 with methacholine, four hours after its administration.

Effect of zinc treatment on cell mediated immunity of chronic renal failure patients.

This study was performed on 13 normal subjects and 34 patients with chronic renal failure (CRF). Oral elemental zinc at a dose of 60 mg/day for four weeks was administered. Delayed type hypersensitivity (DTH) skin tests were performed using the multitest method. Monocyte accessory cell function (MAF) was tested by their ability to support T-cell colony growth in semi-solid cultures stimulated by staph-protein A (SpA). After zinc treatment a significant increase of DTH and MAF was found in all patients with advanced CRF in comparison with controls. These results provide evidence that zinc treatment may restore the impaired cellular mediated immunity of uraemia.

Safety and efficacy of salbutamol aerosol on Dermatophagoides farinae induced bronchospasm in asthmatic patients.

The effects of inhaled salbutamol in bronchial provocation with inhaled house dust mite allergen (HDM) were studied in 20 adult subjects with bronchial asthma and positive skin test to the allergen. There was a significant association between the skin test and the outcome of bronchial challenge, although the magnitude of the skin test reactivity was not significantly correlated with the degree of bronchial reactivity. Metered dose inhaler administration of salbutamol (200 gamma total) was started after antigen produced a fall in mean FEV1 to 31%. Salbutamol treatment returned the FEV1 within 5 min to 66%, and within 45 min to 91% of baseline in all but one patient. It appears that in most asthmatics inhaled salbutamol does significantly and immediately reverse HDM-induced bronchospasm.

Lipopolysaccharide (LPS) modulation of human monocyte accessory cell function in promoting T-cell colonies: inability of LPS and IL-1 to abrogate the need for monocytes with high HLA-DR expression.

The abilities of human monocytes differentially expressing HLA-DR and of lipopolysaccharide (LPS) to influence T-cell colony responses were investigated. Optimal T-cell colony responses stimulated by soluble Staph protein A were crucially dependent on monocytes. Also, monocyte facilitation of colony responses was markedly inhibited by 10 micrograms/ml LPS and the addition of indomethacin reversed this inhibition. In contrast the inhibition of T-cell colony responses with 100 micrograms/ml LPS was not reversed with indomethacin and preincubation experiments with high concentrations of LPS showed the inhibition could be mediated through T cells by mechanisms other than prostaglandins. The treatment of monocytes with a monoclonal anti-HLA-DR reagent + C reduced the frequencies of monocytes expressing high levels of HLA-DR approximately fivefold and the resulting monocytes which expressed low levels of HLA-DR also poorly functioned in the promotion of colony responses compared to controls. LPS in the presence of indomethacin improved the ability of monocytes expressing low levels of HLA-DR to promote colony responses. However, these monocytes consistently failed to augment colony responses to those levels observed with untreated monocytes and their failure was not secondary to deficient interleukin 1 release. These results indicate that although LPS can somewhat potentiate the accessory cell function of certain human monocytes, it cannot abrogate an additional requirement for those monocytes expressing high levels of HLA-DR.

Induction of mast cell secretion by parathormone.

The biologically active fragment of human parathormone (PTH) and intact bovine PTH were found to induce secretion of both serotonin and histamine from rat peritoneal mast cells in vitro. Release of serotonin and histamine was demonstrated with 25 units/ml PTH or higher. This level is within the higher limits of the elevated PTH levels found in advanced uremia. Mast cell secretion by PTH was dose, time and energy dependent and was not cytotoxic. Although mast cell activation was independent of extracellular calcium, it required intracellular calcium, thus resembling the action of certain other peptide secretagogues. Intradermal injection of PTH induced immediate increases in vascular permeability suggesting that PTH could induce mast cell secretion in vivo. Light and electron microscopic observations confirmed mast cell degranulation by exocytosis. These results demonstrate that elevated levels of PTH can induce mast cell secretion in vitro and in vivo and suggest a possible role for mast cells in the pathophysiology of non-allergic disease states.