Showing papers by "University of Bedfordshire published in 1979"

Specific IgE antibodies to platinum salts in sensitized workers

Abstract: A RAST has been developed for the measurement of IgE antibodies specific to platinum chloride complexes in sensitized workers. Human serum albumin covalently linked to Sepharose beads by the cyanogen bromide method was reacted with ammonium tetrachloroplatinite (II) (NH4)2PtCl4. This conjugate was more suitable for the RAST, than conjugates of HSA and the platinum salt prepared in solution and then linked to the activated Sepharose, showing better sensitivity and giving lower levels of non-specific uptake of IgE from sera of non-exposed subjects with high total levels of IgE, e.g. allergic bronchopulmonary aspergillotics.

Soil deformation and shear strength characteristics of some clay soils at different moisture contents

Abstract: Summary The soil deformation and shear strength characteristics of three clay soils were determined at different moisture contents and spherical pressures, using a quick un-drained triaxial compression test. The soils were found to deform either in a compressive way or by brittle fissuring, depending upon the relative values of moisture content, dry density and spherical pressure. The critical state concept of soil deformation can explain qualitatively the behaviour of these spils at high moisture contents but not at low. The Bridgman concept for fracture in brittle materials describes the soil behaviour at low moisture contents. The shear strength of the clay soils tested was more closely related to the soil moisture suction and to the amount of shrinkage which occurred on drying than to the absolute dry bulk density. The influence of moisture content and spherical pressure on the effectiveness of certain cultivation operations are considered.

Clinical correlations between long-term (IgE) and short-term (IgG S-TS) anaphylactic antibodies in atopic and 'non-atopic' subjects with respiratory allergic disease.

Abstract: The sera of atopic and non-atopic persons with allergic pulmonary disorders were examined for long-term sensitizing, IgE and short-term sensitizing heat-stable (S-TS) antibodies which were present separately or together in the sera of some patients sensitive to antigens such as budgerigar serum proteins and Aspergillus funigatus. In fourteen atopic patients with extrinsic asthma, six had both types of antibody to common allergens, and of nine non-atopic patients with crytogenic (intrinsic) asthma, four had only heat-stable short-term sensitizing antibodies. The sera of atopic subjects with type I prick test reactions and positive RAST's, showed specific IgE antibody by baboon PCA tests to budgerigar serum proteins, A. funigatus, Timothy grass pollen extract and hen egg extract, and not to Dermatophagoides farinae, possibly because of naturally occurring mite antibodies in the baboon. The sera of non-atopic asthmatics, who had given negative prick test but positive immediate, dual or late intracutaneous tests, and only late asthmatic reactions, contained precipitins in most cases and gave little or no RAST reaction. On baboon PCA these sera contained either, S-TS antibody alone, or S-TS plus long-term sensitizing antibody, or long-term sensitizing antibody alone. Some of the sera with long-term sensitizing antibody contained blocking antibody which could diffuse away in the 24 hr delay for the baboon PCA test and could also be responsible for the negative RAST. Tests with insoluble anti-IgE immuno-adsorbents on two sera from persons sensitive to aspergillus confirmed that the S-TS activity was not due to IgE, and on two sera with negative RAST and negative prick tests to budgerigar serum antigens confirmed that the 24 hr monkey PCA responses were due to IgE.

1H‐Nuclear‐Magnetic‐Resonance Studies on Glycophorin and Its Carbohydrate‐Containing Tryptic Peptides

Abstract: The proton nuclear magnetic resonance (1H-NMR) spectra of glycophorin and its tryptic sialoglycopeptides were investigated. From the intensities of the assigned resonances it was concluded that all of the residues in the sialoglycopeptides are sufficiently mobile in conformation to give sharp resonances, while in glycophorin this is true for only approximately 80% of the peptide backbone. The resonances of the central sequence of some 20 of the hydrophobic residues are strongly broadened. This region is probably that of α-helical structure which is known to aggregate. The linewidths and intensities of the resonances are not, or only slightly, affected by changing the ionic strength, temperature or by carboxymethylation of the Met-81 residue in glycophorin. Glycophorin was found to bind about 100 mol sodium dodecylsulphate/mol protein as derived from studies on linebroadening of the latter's C-3 to C-11 methylene resonances. The bound dodecyl-sulphate probably increases the mobilities of the hydrophobic residues in the protein as these resonance intensities are increased by the binding. The carbohydrate chains in glycophorin were conformationally mobile; no evidence was found for tight carbohydrate-protein interactions. The relevance of flexible carbohydrate chains in membrane glycoproteins is discussed in relation to cell surface chemistry.

The detection of lactic acid bacteria

Abstract: An examination of lactic acid bacteria involved in beer spoilage has demonstrated that many Pediococci and Lactobacilli are capable of growth on glucose media but incapable of growth on sucrose within 6 days. Some Lactobacilli are incapable of utilizing glucose for growth and are also unable to grow on media based on sucrose. All Lactobacilli studied which could not utilize glucose could utilize maltose. The results presented suggest that the use of a detection medium incorporating both glucose and maltose will result in increased ability to detect lactic acid bacteria.

Seal for a rolling bearing

Abstract: A seal for a rolling bearing has two annular sheet metal members and a resilient sealing element. The two annular members have adjacent axially extending portions which are radially spaced apart to provide an annular axially extending gap. The sealing element is fixed to one annular member, bridges the gap and is in rubbing contact with the other annular member.

Rotary displacement capacitive transducers

Abstract: A rotary displacement capacitive transducer for indicating the angular position of a shaft comprises first and second cylindrical electrodes each electrode having inner and outer conducting members connected together by insulative adhesive and a part cylindrical screen mounted to the shaft is disposed between the electrodes and rotated with the shaft to vary the capacitance between the electrodes. The surfaces of the conducting members define the capacitance of the transducer.

Hypersensitivity Vasculitis: The Acute Phase of Leukocytoclastic (Necrotizing) Lesions

Abstract: There is no inflammatory event in which blood vessels do not participate. There are few allergic responses in which changes in blood vessels are not the main histological feature, as in anaphylaxis, Arthus responses, delayed hypersensitivity, and some cytotoxic reactions. A consideration of “hypersensitivity vasculitis” in the widest interpretation of the term is a review of allergic responses, but the designation tends to be restricted to vasculitis resulting from Arthus or the Arthuslike immune-complex-mediated disorders.