USE OF PROPANDID AND LIGNOCAINE TO MODIFY THE INCREASE IN SERUM POTASSIUM CONCENTRATION FOLLOWING INJECTION OF SUXAMETHONIUM

A technique of general anaesthesia involving the use of propanidid,nitrous oxide, oxygen and halothane followed by a slow injectionof suxamethonium and lignocaine is described. The techniquedecreased the increase in serum potassium concentration thatfollows the injection of suxamethonium and, it is suggested,possesses advantages over the existing practice of the injectionof non-depolarizing neuromuscular blocking drugs before suxamethoniumin an attempt to reduce the frequency of serious cardiac arrhythmia.     

A comparison of glycoprotein biosynthesis in basal cell carcinoma and normal epidermis

Protein and N-linked glycoprotein biosynthesis in normal epidermis and basal cell carcinomas were measured by the incorporation of ³[H] leucine and ³[H] mannose. Compared with normal epidermis, basal cell carcinomas had a reduced overall protein synthesis accompanied by an increased N-linked glycoprotein synthesis. Polyacrylamide gel electrophoresis showed that in the tumours the glycoprotein synthesis was restricted to molecular weight ranges with peaks at 95K (74K) and 38K, whereas in normal epidermis they were found at 95K, 62K, 52K and 43K.     

Restricted T-cell receptor Vβ gene usage in the skin of patients with guttate and chronic plaque psoriasis

A strong association between acute guttate psoriasis and group A, β-haemolytic streptococcal infections is well established. Furthermore, streptococcal M proteins and toxins have been shown to act as superantigens, stimulating subpopulations of T lymphocytes expressing particular Vβ families. We have therefore studied the possible role of streptococcal superantigens in psoriasis by staining peripheral T lymphocytes and skin sections from patients with guttate or chronic plaque psoriasis for the expression of nine TCR Vβ families, using a range of monoclonal antibodies. A marked over-representation of Vβ2⁺ T lymphocytes was observed in the dermis and epidermis of patients in both groups, when compared with T lymphocytes in their peripheral blood. A less marked dermal increase in Vβ5.1⁺ T lymphocytes was also observed in these patients. These findings are consistent with the involvement of a superantigen, possibly streptococcal, in the pathogenesis of psoriasis.     

Linear IgA disease and ulcerative colitis

Seventy adult patients with linear IgA disease were studied. Five (7.1%) also suffered from ulcerative colitis (the prevalence of ulcerative colitis in the U.K. is 0.05%). A further three patients with this association, from other British centres were also reviewed. In all cases, ulcerative colitis preceded the onset of skin disease, by a median of 6.5 years. The reason for this association remains unclear but the abnormalities in colonic mucosal B cells and mucosal IgA₁ production reported in patients with ulcerative colitis may be important in the subsequent development of IgA₁ mediated linear IgA disease.     

The role of cytokines in the generation of skin lesions in dermatitis herpetiformis

The infiltration of polymorphonuclear neutrophils (PMN) into the upper dermis which characterizes the skin lesions of dermatitis herpetiformis (DH) has never been satisfactorily explained. This study has shown that lesional skin of patients with DH has increased expression of endothelial leucocyte adhesion molecules (ELAM) in the deep dermis, combined with a markedly increased staining for interleukin 8 (IL-8) in the basal epidermal layer. Dendritic cells which stained for granulocyte macrophage colony stimulating factor (CM-CSF) were also observed at the dermo-epidermal junction. and this phenomenon was more pronounced in lesional than in uninvolved DH skin. ELAM. IL-8 and GM-CSF are known to promote infiltration and activation of PMN, and it is suggested that these cytokines may play a key role in the generation of DH lesions.     

Protective immunity in the rat model of congenital toxoplasmosis and the potential of excreted-secreted antigens as vaccine components

Toxoplasma infection is a major cause of severe foetal pathology both in humans and in domestic animals, particularly sheep. We have previously reported the development of an experimental model to study congenital toxoplasmosis in the rat. Here we demonstrate that, as in humans, total protection against congenital toxoplasmosis can be achieved regardless of the strain of Toxoplasma gondii used to infect rats, or when initial and challenge infections were carried out with different strains. Chronic infection is associated with a highly specific immunity that involves both B-and T-cell responses beginning at day 10 postinfection. The antibody isotype analysis revealed that whereas immunoglobulin (Ig)G2b is the major elicited isotype, no IgG1 antibodies are detected. T cell proliferation was assayed using crude Toxoplasma extracts or excretory-secretory antigens (ESA). The analysis of T cell supernatants showed the specific secretion of both interleukin-2 and interferon-gamma by activated T cells. Immunization of rats before pregnancy with either crude Toxoplasma extracts or with ESA elicited a B cell response that included antibodies of the IgG1 isotype and conferred on the newborns high levels of protection. Preliminary experiments of immunization using two HPLC-purified ESA, GRA2 and GRA5, conferred, a significant protection although to a lesser extent. This experimental model represents an attractive model for the identification of future vaccine candidates against congenital toxoplasmosis.     

The cell cycle in psoriasis

The cell cycle has been determined in eight in-patients with psoriasis. The cell cycle time for the germinative cell compartment has been found to be 91 h, and the turnover time for the epidermal compartment, beneath the keratin layer to be 120 h (5 days). The duration of the S phase (DNA synthesis) has been found to be 10 h, and that for mitosis 30 min. If it is accepted that the turnover time for the keratin layer is 2 days, then the turnover time for the epidermis in psoriasis is 7 days, and not 3–4 days as previously described.