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T Wadström

Publications and source records attributed to T Wadström.

At least 127 records · Page 7Linked to original sources
PubMed1994

Dyspepsia in general practice: psychological findings in relation to Helicobacter pylori serum antibodies.

Questionnaire data based on traditional concepts for measuring hypochondriasis and depression were related to serological data on Helicobacter pylori antibodies in 110 of 130 consecutive patients, aged 18-65 yr, consulting for dyspeptic symptoms in general practice. Of the patients thirty-seven (33.6%) and seventy-three (66.4%) were classified as H. pylori positives and H. pylori negatives, respectively, the H. pylori positive patients being significantly older than H. pylori negative patients. Factor analyses of the questionnaire data indicated the heterogeneity of each of the traditional concepts for measuring hypochondriasis and depression but succeeded in differentiating orthogonally between two hypochondriasis factors and three depression factors. Hierarchical regression analyses of factor scores, controlling for the influence of age and sex, indicated higher H. pylori antibody activity to be associated with less hypochondriacal signs of anxiety and uneasiness. It is hypothesized, that in dyspepsia without signs of H. pylori infection, somatization may account to a substantial extent for the illness.

Adolescent↗
PubMed1994

Vaccination against Staphylococcus aureus mastitis: immunological response of mice vaccinated with fibronectin-binding protein (FnBP-A) to challenge with S. aureus.

Mice were immunized with fusion proteins encompassing the fibronectin-binding domain of a staphylococcal fibronectin-binding protein (FnBP-A). A specific antibody response against the fibronectin-binding part of the fusion proteins was detected in the serum of all vaccinated animals. The protective potential of these vaccinations was evaluated in a mouse mastitis model, using Staphylococcus aureus, strain SA113, for challenge. The mice vaccinated with FnBP fusion proteins showed a decreased number of bacteria recovered from the mammary glands and significantly reduced cases of severe mastitis. Histopathological examination of tissue from challenged glands of vaccinated mice revealed either no pathological reactions or disseminated inflammatory reactions with focal necrosis whereas four of six examined tissues from challenged glands of non-vaccinated animals showed total necrosis. A combination of FnBP fusion protein with staphylococcal alpha-toxoid did not increase the efficacy of the vaccination and animals vaccinated with alpha-toxoid alone were as sensitive to challenge as those from the non-vaccinated control group. Thus vaccination of mice with recombinant FnBP resulted in significant protection against challenge with S. aureus.

Adhesins, Bacterial↗
PubMed1994

Role of antibodies against fibronectin-, collagen-binding proteins and alphatoxin in experimental Staphylococcus aureus peritonitis and septicaemia in neutropenic mice.

We have investigated the protective role of hyperimmune rabbit IgG against two surface structures of Staphylococcus aureus, i.e. fibronectin-, and collagen-binding proteins as well as alpha-toxin in experimental peritonitis and septicaemia in neutropenic mice pretreated with cyclophosphamide. This treatment markedly decreased clearance of bacteria from mouse organs. With combined immunotherapy given passively bacteria were eradicated more efficiently for all animals sampled, comparative to controls.

Adhesins, Bacterial↗
PubMed1994

Cell surface hydrophobicity and adherence to extra-cellular matrix proteins in two collections of methicillin-resistant Staphylococcus aureus.

Non-specific and specific mechanisms of adherence have been examined in two collections of methicillin-resistant Staphylococcus aureus (MRSA). Determination of hydrophobicity by salt aggregation, hydrophobicity indices and of adherence to the extra-cellular matrix proteins fibronectin, vitronectin, laminin and collagen type 1 have failed to reveal any correlation with phage-type, plasmid profile or antibiogram. Further, the strain collections, made over a period of years in two countries, differ markedly in their adherence characteristics; MRSA are heterogeneous in this respect. Such heterogeneity may explain the polarization of views on the epidemicity or 'virulence' of MRSA. With the exception of adherence to collagen a small group of methicillin sensitive S. aureus had characteristics intermediate between the two groups of MRSA.

Agglutination Tests↗
PubMed1994

Human plasma fibronectin possesses second binding site(s) to Staphylococcus aureus on its C-terminal region.

The existence of a second binding site to Staphylococcus aureus on fibronectin was explored by using a recombinant protein, alb-FnBPA, which was obtained from an Escherichia coli clone containing a part of the gene for fibronectin-binding protein of S. aureus. Limited digestion with trypsin produced a 215K fragment from the B chain of fibronectin by releasing an N-terminal 32 kDa region. This C-terminal large fragment captured alb-FnBPA in spite of lacking the N-terminal binding region to S. aureus. This treatment also produced a 185K fragment from A chain by releasing N-terminal 32 kDa and C-terminal 37 kDa regions, and the 185K fragment possessed no binding ability. Thermolysin digestion was also performed to investigate the effect on the binding of releasing the C-terminal region from both of the chains and to locate the binding region to alb-FnBPA on the tryptic 215K fragment. But this digestion produced no fragment binding to alb-FnBPA except for the N-terminal 24K and its transient precursory fragments. These results indicate that both the N-terminal and the C-terminal regions of fibronectin bind to S. aureus, and suggest that the binding appears to involve cooperation between type III repeats and C-terminal type I repeats.

Binding Sites↗
PubMed1994

Evidence that the heparin-binding consensus sequence of vitronectin is recognized by Staphylococcus aureus.

Binding of heparin-binding form of vitronectin to Staphylococcus aureus was inhibited completely by heparin or by the same form of vitronectin. The binding was inhibited only to about 50% by the non-heparin-binding form of vitronectin, indicating an apparent involvement of the heparin-binding properties in the interaction between vitronectin and S. aureus. This was supported by experiments in which a synthetic peptide (Ala347-Arg361, comprising heparin-binding consensus sequences) was found to partly inhibit bacterial adherence to immobilized vitronectin. A bacterial cell surface protein could bind to the quinquedecapeptide, but not to the highly charged peptides consisting entirely of arginine or lysine, immobilized on microtiter plates and the binding could be competitively inhibited by an excess of soluble peptide. Direct binding of radiolabeled peptide to bacterial cells was also demonstrated, which was rapid, saturable, and pH-dependent. Furtherly a bacterial surface protein having molecular mass of 60 kDa was isolated by affinity chromatography on a quinquedecapeptide-HiTrap-NHS column. Our data suggest that the heparin-binding properties of vitronectin play a role in bacterial recognition.

Amino Acid Sequence↗
PubMed1994

Promotion of Escherichia coli adherence to rubber slices by adsorbed fibronectin.

Biomaterial-associated infections are a problem in the use of endoprosthetic materials in the palliative treatment of malignant obstructive jaundice. Fibronectin has been reported to mediate adherence of bacteria to host tissue and biomaterials. Adsorption of fibronectin to rubber--representing material used for biliary drainage--and subsequent adherence of Escherichia coli strain PSS1 and E. coli strain NG7C (which binds to immobilised fibronectin) were investigated. Quantitative adsorption of fibronectin to rubber slices was studied with 125I-labelled, purified human plasma fibronectin. In buffer solutions, fibronectin showed a high affinity for rubber slices. Adherence of the E. coli strains to uncoated rubber slices was similar and was significantly inhibited by the presence of plasma components and bile. Adherence of E. coli PSS1 to fibronectin-coated slices was poor. In contrast, E. coli NG7C adhered efficiently to coated slices in proportion to the amount of adsorbed fibronectin; adherence was not reduced by the presence of albumin or bile, or the fibronectin-binding ligands gelatin, heparin and fibrinogen. However, pre-digestion of coated slices with trypsin significantly reduced adherence.

Adsorption↗
PubMed1994

Immunological recognition of fibronectin-binding proteins of Staphylococcus aureus and Staphylococcus capitis, strain LK 499.

Antibodies to fibronectin-binding proteins (FnBPs) of Staphylococcus aureus, including binding domain of FnBPA, the D region, or the A-C regions of FnBPB were produced in rabbits and mice. These antibodies were used to characterize cell-associated FnBPs of S. aureus strain Cowan I, S. aureus strain U320 and a coagulase-negative Staphylococcus capitis strain LK499 as well as extracellular FnBPs in culture supernatants of the strain U320. FnBPs of S. aureus were predominantly FnBPA, while FnBPB was hardly detected on the cells or in culture supernatant of these S. aureus strains. Moreover, S. capitis strain LK499 possessed different FnBP(s) compared to S. aureus because the antibodies to S. aureus FnBPs did not recognize FnBP(s) on S. capitis.

Adhesins, Bacterial↗
PubMed1994

Binding of vitronectin and plasminogen to Helicobacter pylori.

We have studied how some extracellular matrix proteins, fibronectin, fibrinogen, collagen type I and type IV, plasminogen and vitronectin bind to Helicobacter pylori. Radiolabelled vitronectin and plasminogen bound to the haemagglutinating H. pylori strain 17874 at a high level (53% and 32%, respectively), type IV collagen showed an intermediate level of binding (16%), while binding by 125I-labelled fibrinogen, fibronectin and collagen type I remained at a low level (5-7%). Both 125I-vitronectin and plasminogen showed a dose-dependent binding to cells of H. pylori 17874. Plasminogen binding by this strain was specific since the binding was inhibited by nonlabelled plasminogen, but not by highly glycosylated glycoproteins such as fetuin and orosomucoid or by a variety of monosaccharides. We have previously shown that 125I-vitronectin shows a specific and saturable binding to H. pylori 17874, and that sialic acid-rich glycoproteins such as fetuin and orosomucoid drastically reduced binding. We now report that a simultaneous incubation of 125I-vitronectin and 125I-plasminogen with cells of H. pylori 17874 showed a total binding approximately similar to the level of binding when either 125I-plasminogen, or 125I-vitronectin only were incubated with the bacterial cells. Nonlabelled vitronectin inhibited the binding of 125I-plasminogen by H. pylori, but nonlabelled plasminogen had no effect on the binding of 125I-vitronectin. Our findings suggest that there are different but probably closely localized binding sites for vitronectin and plasminogen on H. pylori 17874.

Collagen↗
PubMed1994

Interaction of cells of Helicobacter pylori with human polymorphonuclear leucocytes: possible role of haemagglutinins.

The interaction of fluorescein isothiocyanate (FITC)-labelled cells of Helicobacter pylori with human polymorphonuclear leucocytes (PMNs) was studied. Two strains with surface haemagglutinins expressing different receptor specificity were used in order to decide if cell surface haemagglutinins of H. pylori may play a role in lectin-mediated binding to/uptake by phagocytes: (1) strain 17874 (NCTC 11637) which expresses sialic acid-specific haemagglutinin; and (2) strain 17875 (NCTC 11638) which expresses a sialic acid-independent haemagglutinin. Cells of strain 17874 were poorly attached to/ingested by PMNs compared to cells of strain 17875. Pre-treatment of bacteria with fetuin or rabbit antibodies against partly purified sialic acid-specific haemagglutinin enhanced interaction of cells of strain 17874 with PMNs. The enhancement did not occur in the case of strain 17875. Phagocytosis of H. pylori 17874 bacteria was slightly increased by fresh human sera positive for anti-H. pylori antibodies. The results suggest that the sialic acid-specific haemagglutinin complex of 17874 bacteria might disturb their uptake by human PMNs.

Fluorescein-5-isothiocyanate↗
PubMed1994

Interaction of lipopolysaccharides of Helicobacter pylori with basement membrane protein laminin.

The ability of hemagglutinating and poorly hemagglutinating strains of the gastroduodenal pathogen Helicobacter pylori to bind 125I-radiolabelled laminin was quantitated in a liquid phase assay. Although all strains bound laminin, some hemagglutinating strains were good binders of laminin (maximum of 31% binding), whereas poorly hemagglutinating strains bound intermediate to small amounts of laminin (minimum of 6% binding). Since a hydrophobic component of the bacterium has been reported to be involved in binding of laminin (T. J. Trust, P. Doig, L. Emödy, Z. Kienle, T. Wadström, and P. O'Toole, Infect. Immun. 59:4398-4404, 1991), we investigated the role of lipopolysaccharide (LPS) in the interaction of both types of strains with laminin. Although the extent of inhibition varied among strains, laminin binding to hemagglutinating and poorly hemagglutinating strains was inhibited with homologous and heterologous smooth-form LPS. The ability of heterologous rough-form LPS to produce inhibition comparable to that shown by smooth-form LPS indicated that the O side chain of H. pylori LPS was not involved in the interaction. Further inhibition experiments with dephosphorylated LPS, isolated core oligosaccharide, and free lipid A suggested that a phosphorylated structure in the core oligosaccharide mediates the interaction of a hemagglutinating strain of H. pylori with laminin, whereas a conserved nonphosphorylated structure in the core oligosaccharide mediates the interaction of a poorly hemagglutinating strain. Furthermore, we showed that the interaction of H. pylori LPS with 125I-radiolabelled laminin in a solid phase assay was saturable, specific, and inhibitable with unlabelled laminin. It was postulated that the initial recognition and binding of laminin by H. pylori may occur through LPS and that subsequently a more specific interaction with a lectin-like adhesin on the bacterial surface occurs.

Bacterial Adhesion↗
PubMed1994

Dyspepsia in general practice: history and symptoms in relation to Helicobacter pylori serum antibodies.

BACKGROUND: This study was designed to explore the relationships between serologic Helicobacter pylori positivity and demographic, behavioural, and symptomatologic factors in patients consulting for dyspeptic symptoms in general practice. METHODS: H. pylori enzyme-linked immunosorbent assay results and checklist data were collected by general practitioners at three community health centers in southern Sweden from consecutive patients aged 18-65 years with upper abdominal pain or discomfort (dyspepsia). RESULTS: Of the 130 available patients with dyspepsia, 127 agreed to participate, 45 (mean age, 41.2 years) being classified as H. pylori-positive and 82 (mean age, 33.5 years) as H. pylori-negative. Manual workers were diagnosed as H. pylori-positive significantly more often than were non-manual workers (p < 0.05). Of those patients examined earlier by gastroscopy or roentgenography, H. pylori-positives reported stomach or duodenal ulcer significantly more often than did H. pylori-negatives (p < 0.01). H. pylori-positives reported stomach/duodenal ulcer in their parents/siblings to a significantly greater extent than did H. pylori-negatives (45.2% versus 10.1%, p < 0.001). H. pylori-negatives reported stress-generated symptoms significantly more often than did H. pylori-positives (82.9% versus 61.5%, p < 0.01). Hierarchical regression analyses showed that, when age and sex were controlled for, the ability of each of these measures to predict the serologic results remained significant. CONCLUSIONS: Higher levels of H. pylori antibodies in dyspeptic patients appear to be associated with a relatively low self-perception of stress, with manual work, with being older, and with the occurrence, both in the patients themselves and in their close relatives, of stomach/duodenal ulcer.

Abdominal Pain↗
PubMed1994

Coated-bead assay for microbial cell-associated and extracellular protease activity.

An assay utilizing latex beads coated with substrates of 125I-labelled connective tissue proteins is described as an alternative method for quantitating cell-associated and extracellular proteolytic activity of micro-organisms. Proteolytic activity is a function of the amount of 125I-labelled peptides released into the incubation mixture.

Candida albicans↗
PubMed1994

Intravenous Helicobacter pylori induces low levels of TNF-alpha and IL-1 alpha in a murine model.

A murine model for testing cytokine production stimulated by Helicobacter pylori is described. H. pylori induced significantly lower levels of TNF-alpha and IL-1 alpha compared to Escherichia coli or Pseudomonas aeruginosa when injected intravenously. The mean TNF-alpha concentration in serum during 6 h after stimulation with H. pylori was 0.2 ng/ml, whereas E. coli induced 4.7 ng/ml and P. aeruginosa 6.0 ng/ml. This was not explained by rapid elimination of H. pylori as bacteria were present for at least 3 h in the blood. The difference in cytokine induction may be a reflection of the bacteria's different biological qualities. E. coli and P. aeruginosa are both capable of causing systemic disease, whereas H. pylori causes only a local, often low grade, inflammation in the gastric mucosa.

Animals↗
PubMed1994

Staphylococcus aureus fibronectin-binding proteins (FnBPs). Identification of antigenic epitopes using polyclonal antibodies.

Polyclonal antibodies against recombinant fibronectin-binding proteins (gal-FnBP A and ZZ-FnBP B) of Staphylococcus aureus were analyzed by both solid-phase and solution-phase methods. These antibodies were found to bind homologous antigen and to cross-react with heterologous antigen. It was also found that antibodies recognize native FnBP on the cell surface. It has been shown, by the inhibition assay, that the majority of antibodies recognize a fibronectin-binding D1-D2 sequence of FnBP A. Anti-FnBP A Fab fails to bind the D3 sequence, though this peptide used in a solution inhibits binding of fibronectin to immobilized FnBP A, similarly to D1 and D2 peptides. Since the anti-FnBP A antibodies are able to block fibronectin binding to staphylococci by about 50%, it is reasonable to assume that the bacterial receptor has additional binding sites outside the D domain.

Adhesins, Bacterial↗
PubMed1993

Multiple interactions between human vitronectin and Staphylococcus aureus.

Multiple interactions between human vitronectin and Staphylococcus aureus strain V8 were observed. An upward-curved Scatchard plot indicated both high-affinity binding (Kd1 = 7.4 x 10(-10) M) with 260 binding sites per bacterial cell and moderate-affinity binding (Kd2 = 7.4 x 10(-8) M) with 5240 copies per cell. Negative cooperativity of this binding was characterized by its Hill coefficient of less than unity (0.70 +/- 0.08). Up to 60% of the vitronectin-bacteria interaction was unaffected by high ionic strength (i.e., 2.4 M NaCl), and was not inhibited by highly-charged heparin oligosaccharides. Various oligosaccharides (4-20 monosaccharide units) generated by partial deaminative cleavage of heparin were found to affect vitronectin binding to S. aureus. Short-chain-length oligosaccharides increase and long oligosaccharides inhibit vitronectin binding, in accordance with direct association of these saccharides with multimeric vitronectin. A protein having a molecular mass of 60 kDa was identified as a putative high-affinity staphylococcal vitronectin-binding protein. These results indicate that interaction of multimeric vitronectin, mostly present at extracellular matrix sites with multiple recognition sites on the S. aureus surface, may contribute to bacterial colonisation.

Binding Sites↗
PubMed1993

Phospholipid impregnation of abdominal rubber drains: resistance to bacterial adherence but no effect on drain-induced bacterial translocation.

In order to evaluate the effect of surface modification of biomaterials on bacterial adherence and bacterial translocation after intraperitoneal biomaterial implantation, phosphatidylcholine- or phosphatidylinositol-impregnated rubber drain pieces, which had been intraperitoneally implanted in the rat for 2 and 7 days, or unimplanted, were incubated in vitro with 3H-labelled Escherichia coli and Enterobacter cloacae. As compared with unimpregnated pieces, the adherence of bacteria significantly decreased to phosphatidylcholine- and phosphatidylinositol-impregnated rubber drain pieces that were either unimplanted or implanted for 2 days, but not for 7 days. The supplementation of albumin in the medium reduced the adherence of bacteria to the unimplanted, unimpregnated drain pieces, but did not further decrease adherence of bacteria to the unimplanted, phospholipid-impregnated brain pieces. Bacterial growth was inhibited after incubation in nutrient broth supplemented with phospholipids. The incidence of enteric bacterial translocation induced by intraperitoneal drain implantation did not differ between phospholipid-impregnated and unimpregnated drain pieces. Scanning electron microscopy revealed a large amount of biofilm and fibrous deposition on the surface of the implanted, phospholipid-impregnated rubber drain pieces. Thus, phospholipid impregnation of rubber drains reduces bacterial adherence and inhibits bacterial growth, without influencing the incidence of bacterial translocation.

Abdomen↗