Search PubMed⌕ Search

Biomedical subjects

M Kemp

Publications and source records attributed to M Kemp.

At least 109 records · Page 6Linked to original sources
PubMed1988

ELISA analysis of IgA subclass antibodies to dietary antigens. Elevated IgA1 antibodies in children with coeliac disease.

Enzyme immunoassays for the quantitation of IgA1 and IgA2 antibodies to dietary antigens were developed. Serum IgA1 antibodies to bovine serum albumin (BSA) were detectable in 2/30 healthy adults, in 3/26 healthy children, and at high levels in 8/11 children with coeliac disease, without relation to gluten exposure. IgA1 antibodies to ovalbumin (OA) and beta-lactoglobulin (BLG) at high titers were seen in one coeliac child but were otherwise low or absent. IgA2 antibodies to BSA were detectable in 28/48 healthy subjects and in 8/11 coeliac children. IgA2 antibodies to OA and BLG were measurable in a few samples from each group. IgA1 antibodies to the gluten component glycgli were found at low levels in 15/56 normal sera, and anti-glycgli antibodies of the IgA2 subclass in 14/48 sera from healthy persons, also at low levels. IgA1 anti-glycgli antibodies were measurable in 5/11 sera from CD patients on a gluten-free diet. Elevated levels of IgA1 anti-glycgli antibodies were detected in all sera from CD patients challenged with gluten, except in 1 patient with a markedly reduced serum IgA level. In contrast, the IgA2 anti-glycgli antibody levels were unaffected. Thus, increased levels of IgA antibodies to dietary protein antigens in childhood coeliac disease were observed only within the IgA1 isotype.

Adolescent↗
PubMed1988

The ultrastructure of the Schistosoma mansoni egg.

Helminth eggs have resisted analysis by electron microscopy because fixatives, dehydrating agents, and embedding media penetrate these eggs poorly. Slam-freezing at liquid nitrogen temperature followed by freeze-substitution and Spurr's medium embedment provides preservation of the internal structure of the Schistosoma mansoni egg shell, developing miracidium, and perimiracidial structures. The egg shell consists of the three previously described layers (outer microspinous, middle intermediately dense, and inner dense layers) with cribriform pores. A newly described layer (Reynolds' layer) develops subjacent the egg shell and is comprised of densely-packed branching filaments. A single layer of squamous cells (von Lichtenberg's envelope) closely adheres to Reynolds' layer. Between von Lichtenberg's envelope and the embryo is a space (Lehman's lacuna); this space is initially filled with electron-lucent fluid, but subsequently masses of granulofloccular material (Cheever bodies) develop; Cheever bodies are partially membrane bound. Epidermal plates differentiate from superficial cells of the embryonal cell mass, while epidermal ridges differentiate from cells just below the surface of the embryonal cell mass. The cytoplasmic layer (von Lichtenberg's envelope) interposed between the host extracellular fluid and the developing miracidia effect a barrier against a simple passive diffusion; this infers that complex macromolecules, such as schistosomal egg antigen, undergo active, and perhaps selective, transport in or out of the egg.

Animals↗
PubMed1987

Amniotic membrane production of prostaglandin F2 alpha is reduced in dysfunctional human labor: results of in vivo and in vitro studies.

Mobilization of arachidonic acid from glycerophospholipids and prostaglandin (PG) release from fetal membranes were studied in women with dysfunctional labor in the absence of cephalopelvic disproportion or fetal malposition. Using superfusion of intact amnion and chorion, we found a slight decrease in PGE and a more significant decrease in PGF release by the amniotic side of the fetal membrane obtained from women with dysfunctional labor compared to that in women with normal labor (PGE: normal labor, 2992 pg/cm2.h; dysfunctional labor, 1846 pg/cm2.h; P less than 0.05; PGF: normal labor, 662 pg/cm2.h; dysfunctional labor, 204 pg/cm2.h; P less than 0.02). Release of both prostanoids was significantly greater from the amniotic side in tissues obtained after labor compared to that in prelabor tissue. Analysis of arachidonic acid (by gas liquid chromatography) and phospholipid content (by two-dimensional thin layer chromatography) confirmed metabolic disposal of arachidonic acid from the amnion after the onset of labor. However, no difference in either phospholipid or phospholipase A2-releasable arachidonic acid of individual phospholipid classes was found in amnion tissue from women with normal and dysfunctional labor, suggesting similar activities of phospholipase A2 in these two groups. The finding of decreased free and phospholipase A2-releasable arachidonic acid of the total lipid extract of the amnion of women with dysfunctional labor could suggest further metabolic exhaustion of the substrate or failure of liberation of this fatty acid from glycerophospholipids by enzymes other than phospholipase A2, such as phospholipase C or diacyl and monoacylglycerolipases.

Adult↗
PubMed1986

Immunohistochemical analysis of the cellular infiltrate in multiple sclerosis lesions.

Immunohistochemical staining of 16 brains post mortem from patients with progressive multiple sclerosis and of two biopsy specimens from patients with acute demyelinating disease was performed using a panel of monoclonal antibodies reactive with T cells and T-cell subsets, B cells, and Ia (HLA-DR) antigens. Lymphocytic perivascular cuffs were most prominent at the edge of active plaques and were occasionally seen in areas with no evidence of demyelination or macrophage infiltration. Perivascular cuffs consisted predominantly of T cells and Ia+ cells, with many T8+ cells and variable numbers of T4+ cells. T8/T4 ratios in cuffs varied between 1:1 and 50:1. In normal-appearing white matter, cuffs were sparse and were predominantly T8+. The distribution of T cells in the parenchyma resembled that seen in perivascular cuffs, namely, predominantly T8+ cells and variable numbers of T4+ cells. Many Ia+ cells were present in active lesions, and the majority of these cells appeared, by histological criteria, to be macrophages. Tissue macrophages were also stained lightly by the anti-T4 antibody. No brain had more T4+ than T8+ cells, determined using both T4 and Leu3a monoclonal antibodies. B1+ cells were rare. These results suggest that the cellular infiltrate in multiple sclerosis consists predominantly of T cells and macrophages and that there is an overrepresentation of T8+ cells compared with T4+ cells.

Antibodies, Monoclonal↗
PubMed1986

Relationship between levels of rheumatoid factor isotypes and complement component C3 conversion in blood from patients with rheumatoid arthritis.

Conversion of complement component C3 in plasma from rheumatoid arthritis patients was measured by two different methods. One of the methods gives an estimation of C3 conversion by ELISA measurement of neodeterminants present on the C3d moiety; the other method measures C3 split products expressing D, but not C, epitopes by rocket immunoelectrophoresis (RIE) with intermediate anti-C3c gel. Results from 20 RA patients obtained by the two methods did not correlate significantly (R = 0.52, 0.02 less than p less than 0.05). The results were compared to the level of rheumatoid factors (RFs) of IgG, IgM, and IgA class in serum. A significant correlation was found between the concentration of C3d measured by RIE and level of IgG RFs, whereas neither IgM nor IgA RFs showed correlation to complement activation. The results of the ELISA estimation of C3 activation showed no correlation with the RF level.

Arthritis, Rheumatoid↗
PubMed1985

Analysis of rheumatoid factors by a biotin-avidin based isotype-specific ELISA.

A one day enzyme immunoassay for the detection of rheumatoid factors of the IgG, IgM, and IgA class is described. The assay utilizes rabbit IgG as solid-phase reactant and the biotin-avidin interaction for the coupling of enzyme to indicator antibody. Three different indicator antibodies discriminated effectively between rheumatoid arthritis patients and normal subjects. F(ab')2 fragments of goat antibodies were found best suited for the test. Rheumatoid factor activity was expressed in U/ml by comparing samples to an internal standard, which was related to the WHO international reference serum for rheumatoid arthritis. Rheumatoid factor activity (U/ml) in the IgM-specific assay showed a close correlation to the latex agglutination titer. Avidity indices estimated from the slopes of the dose response curves of test sera were significantly higher for rheumatoid arthritis patients than for a group of healthy persons, indicating a higher avidity of the rheumatoid factors in the patients' sera.

Adult↗
PubMed1984

Potential inhibitors of tyrosine hydroxylase and dopamine-beta-hydroxylase.

A series of methyl-substituted 1,2,3,4-tetrahydrocarbazoles was synthesized and screened for in vitro activity against tyrosine hydroxylase and dopamine-beta-hydroxylase. The most potent compounds were evaluated for inhibition of norepinephrine biosynthesis in rats. The results indicated no significant decrease in norepinephrine levels at three dosage levels.

Animals↗
PubMed1984

Serum angiotensin-converting enzyme and delayed hypersensitivity in pulmonary tuberculosis.

In contrast to sarcoidosis, there was no difference between serum angiotensin-converting enzyme (ACE) levels in a group of 100 adult Indonesian patients with active pulmonary tuberculosis and in 108 matched healthy control subjects. There was a significant inverse correlation between the diameter of the cutaneous reaction to tuberculin and serum ACE levels. It is postulated that, as both delayed hypersensitivity and ACE synthesis within granulomas appear to be the result of T-cell induced secretory activities of macrophages, this inverse relationship results from competition for receptor sites for the relevant signal molecules on the macrophage surface.

Adolescent↗
PubMed1981

Salivary and urine theophylline levels in management of childhood asthma.

It is not possible to predict the plasma theophylline levels that can be achieved using slow-release aminophylline based on body weight or surface area. Improvement in FEV1 is directly related to increasing serum theophylline level, justifying the need for measuring levels in order to optimize therapy. As repeated venesection in children is unpleasant we have studied a simple method using saliva. Simultaneous blood and salivary theophylline levels correlated sufficiently well for salivary levels to be used for monitoring purposes. Urine levels did not correlate as well, but could be used for checking compliance.

Adolescent↗