No description available.

Antral mucosal biopsies were examined microbiologically and histologically for the presence of Campylobacter pylori in 224 patients with upper gastrointestinal symptoms. One hundred and eighty three (83%) patients were found to harbour Campylobacter pylori in their gastric mucosa. Campylobacter pylori was strongly associated with the presence of histological gastritis (93%) and was detected in only 10% of 30 patients whose gastric biopsies showed normal histology. Endoscopically diagnosed duodenal lesions were more strongly associated with the presence of Campylobacter pylori than were gastric lesions (p<0.001). A variety of laboratory methods were evaluated to determine the sensitivity and specificity to detect the presence of Campylobacter pylori. Histology was the most sensitive and specific method to detect the presence of Campylobacter pylori. Although culture was highly specific, it was less sensitive than histology in detecting Campylobacter pylori in gastric antral mucosal specimens. The "conventional" gastric urease assay, although specific, needs be performed under controlled conditions (37°C) for optimal results. The "one-minute" urease assay was more sensitive than the "conventional" gastric urease assays and was highly specific. ELISA to detect specific-IgG antibodies to Campylobacter pylori was a moderately sensitive non-invasive method to detect Campylobacter pylori infection, but was non-specific. / Thesis (M.Med.)-University of Natal, 1988.

Lactoferrin (Lf) is an iron binding protein produced in mammals. It has antimicrobial and immunomodulatory properties. Some bacteria that regularly colonize mammalian hosts have adapted to living in high Lf environments. Helicobacter pylori, which inhabits the human gut, was chosen as a model organism to investigate how bacteria may adapt to Lf. H. pylori was able to use iron from fully saturated human Lf (hLf) in various low iron media, achieving growth levels similar to the ironreplete control. Partially saturated hLf decreased growth, yet both partially saturated bovine Lf (bLf) and hLf were able to increase internalization of bacteria into mammalian tissue culture cells. A substantially larger increase in internalization was seen when bacteria were supplemented with hLf in low iron conditions, possibly mediated by iron-regulated cellular receptors or bacterial lactoferrin binding proteins. In eukaryotes, Lf is known to bind and facilitate internalization of DNA into cells and sometimes the nucleus, and upregulate gene expression. Here, one hundred bacterial genomes were surveyed for known Lf binding sites as an indication that Lf had similar functions using bacterial DNA. While the frequency and location of Lf binding sites suggest they occur at random, their presence in all genomes suggests that Lf may be able to act as a vector for bacterial DNA, and facilitate the movement of genes between species. Lf is being widely considered for commercial and therapeutic uses, with significant interest in producing it in genetically modified organisms (GMO). Widespread production and use of Lf could increase the number of bacteria that are adapted to it. How Lf interacts with bacteria adapted to it, and the ability of it to act as a DNA vector, may have relevance for GMO risk assessment.

No description available.

Lactoferrin (Lf) is an iron binding protein produced in mammals. It has antimicrobial and immunomodulatory properties. Some bacteria that regularly colonize mammalian hosts have adapted to living in high Lf environments. Helicobacter pylori, which inhabits the human gut, was chosen as a model organism to investigate how bacteria may adapt to Lf. H. pylori was able to use iron from fully saturated human Lf (hLf) in various low iron media, achieving growth levels similar to the ironreplete control. Partially saturated hLf decreased growth, yet both partially saturated bovine Lf (bLf) and hLf were able to increase internalization of bacteria into mammalian tissue culture cells. A substantially larger increase in internalization was seen when bacteria were supplemented with hLf in low iron conditions, possibly mediated by iron-regulated cellular receptors or bacterial lactoferrin binding proteins. In eukaryotes, Lf is known to bind and facilitate internalization of DNA into cells and sometimes the nucleus, and upregulate gene expression. Here, one hundred bacterial genomes were surveyed for known Lf binding sites as an indication that Lf had similar functions using bacterial DNA. While the frequency and location of Lf binding sites suggest they occur at random, their presence in all genomes suggests that Lf may be able to act as a vector for bacterial DNA, and facilitate the movement of genes between species. Lf is being widely considered for commercial and therapeutic uses, with significant interest in producing it in genetically modified organisms (GMO). Widespread production and use of Lf could increase the number of bacteria that are adapted to it. How Lf interacts with bacteria adapted to it, and the ability of it to act as a DNA vector, may have relevance for GMO risk assessment.

Diss. (sammanfattning) Göteborg : Göteborgs universitet, 2007. / Härtill 5 uppsatser.

Diss. (sammanfattning) Umeå : Univ., 2003. / Härtill 4 uppsatser.

Diss. (sammanfattning) Umeå : Univ., 2004. / Härtill 4 uppsatser. I publ. felaktig serietitel: Umeå University medical dissertation.

Thesis (Ph. D.)--University of Hong Kong, 2009. / Includes bibliographical references (leaves 132-157) Also available in print.

Thesis (Ph. D.)--University of Hong Kong, 2010. / Includes bibliographical references (leaves 181-207). Also available online.