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Biomedical subjects

D M Weir

Publications and source records attributed to D M Weir.

At least 73 records · Page 4Linked to original sources
PubMed1991

ABO blood group, secretor status and detection of Helicobacter pylori among patients with gastric or duodenal ulcers.

Patients (454) referred for gastroscopy to the General Hospital of Athens were examined to determine (1) if non-secretors were over-represented among patients with ulcers and (2) if there was an association with ABO blood group or secretor status and carriage of Helicobacter pylori. Compared with the local population, among patients with either gastric ulcer (51) or duodenal ulcer (96) there was a significant increase in the proportion of those who were blood group O (P less than 0.025); however, there were no significant differences in the proportions of non-secretors. H. pylori was identified in 62% of the 454 patients: 59.5% of those without evidence of ulcers; 62.5% of those with gastric ulcer; 88% of those with duodenal ulcer (P less than 0.0005). These bacteria were cultured more often and in higher numbers from patients with duodenal ulcer (P less than 0.025). There was no association between ABO blood group and prevalence of H. pylori. The prevalence of H. pylori among non-secretors with gastric ulcer (12.5%) was significantly lower than that for non-secretors with duodenal ulcer (100%) (P less than 0.0005). This was not observed for secretors.

ABO Blood-Group System↗
PubMed1991

Chronic atrophic oral candidiasis among patients with diabetes mellitus--role of secretor status.

Non-diabetic individuals who are non-secretors of blood group antigens are prone to superficial infections by Candida albicans. In this study, 216 patients with diabetes mellitus who were denture wearers were examined for the presence or absence of denture stomatitis. There was an overall trend for non-secretors to be prone to denture stomatitis compared with secretors. Stepwise linear discriminant analysis was used to dissect the contribution of secretor status and other variables to the development of the disease. Secretor status was found to be a contributory factor among patients with non-insulin dependent diabetes but not among those with insulin-dependent diabetes. The possible reasons for this are discussed.

ABO Blood-Group System↗
PubMed1991

Alterations in monocyte receptor function in type 1 diabetic patients with ketoacidosis.

The level of expression of three monocyte cell surface receptors was studied in seven patients with Type 1 (insulin-dependent) diabetes admitted to hospital with ketoacidosis. After recovery of metabolic control the monocyte carbohydrate-binding ('lectin-like') receptors that recognize bacterial cell wall sugars and receptors for complement components were reduced in the patients compared with normal control subjects. This was in contrast to the expression of the receptor for the Fc portion of immunoglobulin which remained unaltered. Compared with the control subjects the level of 'lectin-like' receptors was reduced by 22.8 +/- 6.5% (p less than 0.05) on admission to hospital and 12.1 +/- 1.7% (p less than 0.001) 6 weeks later when metabolic control had been established. The expression of complement receptors was 33.8 +/- 8.1% (p less than 0.01) lower than normal subjects when the diabetic patients suffered from ketoacidosis and 8.6 +/- 1.6% (p less than 0.01) lower than control subjects when patients had recovered metabolic control. The increased susceptibility to infection seen in diabetic patients, and the high incidence of infection in patients with ketoacidosis, may be partially the result of these changes in monocyte recognition mechanisms.

Adult↗
PubMed1991

Klebsiella pneumoniae glycoprotein RU-41740 enhances resistance of mice against Mycoplasma arthritidis-induced arthritis.

The effect of a purified glycoprotein extract from Klebsiella pneumoniae with non-specific immunostimulating properties (RU 41740) on the development and course of mycoplasma arthritis was investigated. Male A/J mice aged 2-3 months were given RU-41740 either intraperitoneally (i.p.) or orally prior to injection with Mycoplasma arthritidis. RU-41740 injected i.p. at 0.1 mg kg-1 or given orally at 1 mg kg-1 prior to the infection and subsequently on alternate days enhanced the resistance of mice to mycoplasma arthritis (P less than 0.001). Doses of 1 mg kg-1 i.p. or 10 mg kg-1 orally did not modify the course of the arthritis significantly, probably due to immunosuppressive factors from monocytes. It is suggested that RU-41740 protects the mice by stimulating macrophages. This immunostimulant might prove useful in the treatment of mycoplasma diseases, especially in the immunocompromised host.

Adjuvants, Immunologic↗
PubMed1991

In vitro binding of Helicobacter pylori to human gastric mucin.

The in vitro binding of four Helicobacter pylori strains to human gastric mucin was studied with an enzyme-linked immunosorbent assay. All four strains were found to bind to purified mucin. Neuraminidase treatment and nonspecific oxidation of mucin decreased bacterial adherence to the macromolecule. Mucin preparations were also found to inhibit attachment of H. pylori to HEp-2 monolayers.

Bacterial Adhesion↗
PubMed1990

Secretor status, smoking and carriage of Neisseria meningitidis.

A survey of ABO blood groups, secretor status and smoking habits among 389 students and staff of a school in which there was an outbreak of meningococcal disease found no difference in the distribution of the ABO blood groups but a significantly higher proportion of non-secretors (37.6%) in the population examined compared with that reported for previous surveys of the neighbouring population in Glasgow (26.2%) (P less than 0.0005). There was also a significantly higher proportion of non-secretors among carriers of meningococci (47%) compared with non-carriers (32%). Increased carriage of meningococci among non-secretors might contribute to the increased susceptibility of individuals with this genetic characteristic to meningococcal disease observed in previous studies. Although passive exposure to cigarette smoke has been associated with meningococcal disease, there was no association between passive smoking and carriage. There was, however, a significant association between active smoking and carriage.

ABO Blood-Group System↗
PubMed1990

Semi-quantitative determination of H type 1 and type 2 antigens on buccal epithelial cells and in saliva of secretors and non-secretors.

The amount of H antigens on buccal epithelial cells (BEC) of secretors and non-secretors was measured by flow cytometry. H type 1 and H type 2 on BEC were detected with fluorescein-labelled Ulex europaeus lectin, and H type 2 was measured with mouse monoclonal antibody. Between 3.5 and 6 times more H antigen was detected on cells from secretors compared with cells from non-secretors. The level of H type 2 was the same on BEC of secretors and non-secretors. Adsorption of H type 1 antigen from secretor saliva onto non-secretors BEC was demonstrated. A simple and sensitive ELISA method was developed for the determination of H in saliva with biotin-labelled Ulex lectin. This system provides a simple means for measuring the amount of H present in saliva and for the determination of secretor status.

ABO Blood-Group System↗
PubMed1990

Inhibition of Helicobacter pylori haemagglutination activity by human salivary mucins.

Thirty isolates of Helicobacter pylori from gastric biopsies agglutinated human erythrocyte suspensions. Crude mucin preparations derived from saliva of 20 different donors were examined for their ability to inhibit haemagglutination. All mucin preparations exhibited strong inhibitory activity. Removal of sialic residues from mucin preparations by treatment with neuraminidase resulted in a substantial reduction of their inhibitory activity. The mucin preparations had no bactericidal or aggregation activity for H. pylori. These results are discussed in the context of the role of mucins in colonization of the gastric mucosa by H. pylori.

Gastric Mucosa↗
PubMed1990

Seroepidemiology of Helicobacter pylori infection in Greece.

Helicobacter pylori infection is strongly associated with chronic gastritis and peptic ulceration. As the prevalence of H. pylori infection in southern European populations is not known, a serological survey of 1069 samples from three different age groups in the Greek population was carried out with an enzyme-linked immunosorbent assay (ELISA) for antibodies to these bacteria. The antigen was an ultracentrifuged supernate of whole cell sonicates of 5 isolates of H. pylori assessed by electrophoresis and by immunoblotting with negative and positive sera. The sensitivity of the test was 97.43% and the specificity 100% for IgG antibodies; IgA and IgM antibodies to the antigen preparation were not found. Antibodies to H. pylori were detected among 39.4% of children aged 1-10 years, 67.1% of recruits (20-27 years) and 70% of blood donors (20-50 years). The prevalence of antibodies did not differ with sex in each of the age groups. The proportion of individuals with antibodies to H. pylori was higher in the younger age groups than those reported for similar age groups in western Europe.

Adult↗
PubMed1990

Secretor status and infection in patients with Graves' disease.

We have demonstrated that the inability to secrete the water soluble glycoprotein form of the ABO blood group antigens into saliva is significantly more common in patients with Graves' disease than control subjects (40% vs 27%: P less than 0.025) but not among those with Hashimoto's thyroiditis or spontaneous primary atrophic hypothyroidism. Non-secretion is associated with increased susceptibility to infection and to asymptomatic carriage of some microorganisms. Although Yersinia enterocolitica has been found to express antigen cross reactive with the TSH receptor, we did not find an increased prevalence of Yersinia species in the faeces of 107 patients with Graves' disease. The isolation rate (less than 1%) was similar to that observed in the local population with diarrhoeal illness. Salivary IgA levels determined by whole cell ELISA with Y. enterocolitica 03 were not elevated in the majority of specimens examined. The results suggest that in contrast to reports from Scandinavia, there is no strong evidence that yersiniae play a role in the pathogenesis of Graves' disease among patients in South east Scotland. Non-secretors are significantly over represented among patients with several other autoimmune diseases; however, with the exception of antitubulin antibodies, non-secretors with Graves' disease did not have more antibodies to other human antigens than secretor patients.

ABO Blood-Group System↗
PubMed1989

The Stonehouse study: secretor status and carriage of Neisseria species.

The genetically determined inability to secrete the water-soluble glycoprotein form of the ABO blood group antigens into saliva and other body fluids is a recognized risk factor for meningococcal disease. During a community-wide investigation of a prolonged outbreak of disease due to a B15:P1.16 sulphonamide-resistant strain of Neisseria meningitidis in Stonehouse, Gloucestershire (the Stonehouse survey), the ABO blood group and secretor status of almost 5000 residents was determined. The proportion of non-secretors in the Stonehouse population was significantly higher than the proportion of non-secretors among blood donors in the South West Region and in England generally. Seven of 13 Stonehouse residents with meningococcal disease who were tested were found to be non-secretors, a high proportion. The outbreak in Stonehouse cannot be explained solely in terms of the increased proportion of non-secretors. There was no clear correlation between the proportions of non-secretors in different areas within the town and the incidence of cases of meningococcal disease. Carriers of meningococci, whether outbreak or other strains, were not more likely to be non-secretors. The reasons why non-secretors are more susceptible to meningococcal disease remain to be determined, but they do not appear to be related to carriage of meningococci.

ABO Blood-Group System↗
PubMed1989

Carbohydrates as recognition molecules in infection and immunity.

Consideration of host-parasite interactions encompasses a wide range of phenomena from adhesion to epithelial surfaces to interactions with cells of the immune system. This review focuses on the role of carbohydrates as recognition molecules in these complex interactions. The abundant glycoproteins and glycolipids of cell surfaces of both prokaryotic and eukaryotic cells have the ability to exist in a variety of spatial configurations through alpha- and beta-linkages and the formation of branched structures. This ability carries with it the opportunity of acting as informational molecules greater than that possible for proteins or nucleic acids. The blood group substances are probably the best characterized of these carbohydrate containing molecules. Whilst at present a detailed understanding of the importance of these molecules in host-parasite interaction is lacking, the material covered in this discussion emphasizes the way in which carbohydrate based recognition has been shown to be involved and may provide the basis for further understanding.

Animals↗
PubMed1989

Blood group, secretor status and susceptibility to bacterial meningitis.

Epidemiological evidence is summarized for associations of ABO blood group and secretor status with susceptibility to invasive disease due to capsulate organisms responsible for the majority of bacterial meningitis. Host-parasite interactions that might underly these findings are proposed and evidence to support or refute them provided.

Bacterial Infections↗
PubMed1989

Characterization of Escherichia coli strains isolated from urine of secretors and non-secretors.

Strains of Escherichia coli isolated from urine of secretors (242) and non-secretors (121) were compared for their serotype and their ability to express mannose-sensitive (MS) haemagglutinins and mannose-resistant (MR) haemagglutinins and to produce haemolysin. The results of the survey refuted our hypothesis that strains with characteristics associated with virulence, those with MR haemagglutinins and/or haemolysins, would be isolated more frequently from non-secretors. MR haemagglutinins were detected among 36.4% of isolates from secretors and 27.3% of isolates from non-secretors. Haemolysin production was detected among 19.8% of isolates from secretors and 12.5% of isolates from non-secretors. Both MR haemagglutinins and haemolysin were detected only on 12.4% of strains from secretors and 6.7% of strains from non-secretors.

ABO Blood-Group System↗
PubMed1989

Non-secretion of ABO blood group antigens: a host factor predisposing to recurrent urinary tract infections and renal scarring.

In a study of 718 women referred for specialist investigation for recurrent urinary tract infections, 250 (34.8%, P less than 0.01) were non-secretors. The proportion of non-secretors among the women with renal scars (42.6%) was higher than that found for women with no evidence of renal scars (36.6%). Among 29 patients in whom symptoms began in childhood or adolescence, 51.7% were non-secretors. The proportion of non-secretors among individuals with renal scars in this study (42.6%) and that reported in the accompanying paper for Swedish children (40%) suggests that non-secretion might influence the pathogenic sequelae of these infections. Possible host-parasite interactions underlying the increased proportion of non-secretors among women with recurrent urinary tract infections and those leading to development of renal scars are discussed.

ABO Blood-Group System↗
PubMed1989

Non-secretion of blood group antigens and susceptibility to infection by Candida species.

One of the innate defences against superficial infections by Candida species appears to be the ability of an individual to secrete the water-soluble form of his ABO blood group antigens into body fluids. There was a significantly higher number of non-secretors (48.9%) among 174 patients with either oral or vaginal candida infections compared with the proportion of non-secretors in the local population (26.6%). The protective effect afforded by the secretor gene might be due to the ability of glycocompounds in the body fluids of secretors to inhibit adhesins on the surface of the yeast. In attachment studies, preincubation of blastospores with boiled secretor saliva significantly reduced their ability to bind to epithelial cells. Non-secretor saliva did not reduce the binding and often enhanced the numbers of attached yeasts. Possible host-parasite interactions underlying the susceptibility of non-secretors to candida and other infections are discussed.

ABO Blood-Group System↗
PubMed1989

Lewis a blood group antigen of non-secretors: a receptor for candida blastospores.

This study tested the hypothesis that the Lewis a blood group antigen found predominantly on the cells of non-secretors might be one of the receptors for Candida species. Binding of strain 3118C to epithelial cells from either secretor or non-secretor donors was not inhibited by treating the cells with anti-Lewis a or anti-Lewis b antisera. Binding of strain 3091 to non-secretor cells was inhibited by pretreating the cells with anti-Lewis a, but this was not observed for secretor cells. The results suggest that Lewis a might be one of the receptors for some yeast strains.

Binding Sites↗