Publications by authors named "Anna Bates"

Introduction And Aims: Increasing treatment uptake among people who inject drugs (PWID) with chronic hepatitis C virus (HCV) infection is integral to eliminating viral hepatitis. This study explored the role of community-based outreach in engaging and retaining Australian PWID in the testing component of the HCV care cascade.

Design And Methods: Semi-structured interviews were conducted with 28 PWID, including new initiates to injecting and those from culturally and linguistically diverse (CALD) backgrounds, who acquired HCV infection while enrolled in a community-based prospective observational study of hepatitis C vaccine preparedness in Sydney.

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Background: Studies have shown intimate injection partners engage in higher rates of syringe and injecting equipment sharing. We examined the drug use context and development of injection drug use behaviors within intimate injection partnerships.

Methods: In-depth interviews (n=18) were conducted with both members of nine injecting partnerships in Sydney, Australia.

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Cambodia's 100% Condom Use Programme is credited with an increase in consistent condom use in commercial sexual interactions and a decrease in HIV prevalence among female sex workers (FSWs). There has been little improvement in condom use between FSWs and non-commercial partners, prompting calls for more innovative approaches to increasing condom use in these relationships. To understand why condoms are used or not used in sexual interactions involving FSWs, we examined condom negotiation across different types of relationships.

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We describe using major outer membrane protein (MOMP) typing as a screen to compare the Campylobacter jejuni porA gene sequences of clinical outbreak strains from human stool with the porA sequences of dairy farm strains isolated during two milk-borne campylobacteriosis outbreak investigations in California. The genetic relatedness of clinical and environmental strains with identical or closely related porA sequences was confirmed by multilocus sequence typing and pulsed-field gel electrophoresis analysis. The first outbreak involved 1,644 C.

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A recent widespread outbreak of Escherichia coli O104:H4 in Germany demonstrates the dynamic nature of emerging and re-emerging food-borne pathogens, particularly STECs and related pathogenic E. coli. Rapid genome sequencing and public availability of these data from the German outbreak strain allowed us to identify an O-antigen-specific bacteriophage tail spike protein encoded in the genome.

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Background: A safe and efficacious vaccine may be the most efficient and cost-effective strategy for controlling the hepatitis C virus (HCV) epidemic among people who inject drugs (PWID) and several candidates are in development. However, little is known about the factors that influence willingness to participate (WTP) in candidate HCV vaccine trials among this group.

Methods: HCV seronegative PWID recruited between 2008 and 2010 as part of a prospective observational cohort study in Sydney, Australia were asked whether they would be willing to participate in a future candidate hepatitis C vaccine trial and to provide reasons to explain their decision.

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Six protein biomarkers from two strains of Escherichia coli O157:H7 and one non-O157:H7, nonpathogenic strain of E. coli have been identified by matrix-assisted laser desorption ionization time-of-flight-time-of-flight tandem mass spectrometry (MALDI-TOF-TOF-MS/MS) and top-down proteomics. Proteins were extracted from bacterial cell lysates, ionized by MALDI, and analyzed by MS/MS.

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We report covalent attachment via a thiol ester linkage of 3,5-dimethoxy-4-hydroxycinnamic acid (sinapinic acid or SA) to cysteine-containing protein biomarkers from bacterial cell lysates of E. coli analyzed by matrix-assisted laser desorption/ionization (MALDI) mass spectrometry when using SA as the matrix. Evidence to support this conclusion is the appearance of additional peaks in the MS spectra when using SA, which are absent when using alpha-cyano-4-hydroxycinnamic acid (HCCA).

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Background: Feasibility studies are an important component of preparations for field trials of biomedical prevention interventions, including vaccines.

Methods: We conducted ethnographic fieldwork to assess feasibility, including eligibility and willingness to participate, prior to recruitment of a prospective observational study of hepatitis C negative people who inject drugs (PWID) in Sydney, Australia. Five staff conducted ethnographic fieldwork in 16 locations during 2008.

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We have developed web-based software for the rapid identification of protein biomarkers of bacterial microorganisms. Proteins from bacterial cell lysates were ionized by matrix-assisted laser desorption ionization (MALDI), mass isolated, and fragmented using a tandem time of flight (TOF-TOF) mass spectrometer. The sequence-specific fragment ions generated were compared to a database of in silico fragment ions derived from bacterial protein sequences whose molecular weights are the same as the nominal molecular weights of the protein biomarkers.

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Introduction And Aims: The acceptability of testing methods and procedures has implications for uptake of blood-borne virus screening in sentinel samples of injecting drug users (IDUs) likely to participate in surveillance. The aim of the current study was to determine the acceptability of three methods of hepatitis C virus (HCV) testing among injecting drug users (IDUs): oral fluid, capillary blood and venous blood sampling.

Design And Methods: A cross-sectional survey of IDUs was conducted in inner-city Sydney in 2005 for a laboratory validation study of HCV antibody testing.

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Some strains of Pseudomonas aeruginosa produce R-type pyocins, which are high-molecular-weight phage tail-like protein complexes that have bactericidal activity against other Pseudomonas strains. These particles recognize and bind to bacterial surface structures via tail fibers, their primary spectrum determinant. R-type pyocins kill the cell by contracting a sheath-like structure and inserting their hollow core through the cell envelope, resulting in dissipation of the cellular membrane potential.

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Inactivation of luxS, encoding an AI-2 biosynthesis enzyme, in Campylobacter jejuni strain 81-176 significantly reduced colonization of the chick lower gastrointestinal tract, chemotaxis toward organic acids, and in vitro adherence to LMH chicken hepatoma cells. Thus, AI-2 production in C. jejuni contributes to host colonization and interactions with epithelial cells.

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In this work we report on a high-throughput mass spectrometry-based technique for the rapid high-resolution identification of Campylobacter jejuni strain types. This method readily distinguishes C. jejuni from C.

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Histo-blood group antigens (HBGA) expressed on cells in the human GI tract have been shown to function as receptors for noroviruses. In concordance with earlier reports (Backer et al., 1997; Yamamoto and Yamamoto, 2001), this study found that individual pigs are either HBGA type A positive or type H1 (type O) positive.

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Env-specific IgG and IgM were detected in 25 and 60%, respectively, of volunteers immunized with NYVAC expressing clade C gp120. The serum sample with the highest IgM titre but undetectable IgG neutralized the homologous isolate with a reciprocal IC90 titre of 7.8 in the absence of complement, and 24.

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We have identified several protein biomarkers of three Campylobacter jejuni strains (RM1221, RM1859, and RM3782) by proteomic techniques. The protein biomarkers identified are prominently observed in the time-of-flight mass spectra (TOF MS) of bacterial cell lysate supernatants ionized by matrix-assisted laser desorption/ionization (MALDI). The protein biomarkers identified were: DNA-binding protein HU, translation initiation factor IF-1, cytochrome c553, a transthyretin-like periplasmic protein, chaperonin GroES, thioredoxin Trx, and ribosomal proteins: L7/L12 (50S), L24 (50S), S16 (30S), L29 (50S), and S15 (30S), and conserved proteins similar to strain NCTC 11168 proteins Cj1164 and Cj1225.

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We have identified a prominent approximately 10-kDa protein biomarker observed in the matrix-assisted laser desorption/ionization time-of-flight mass spectra (MALDI-TOF-MS) of cell lysates of five thermophilic species of Campylobacter: jejuni, coli, lari, upsaliensis, and helveticus. The biomarker was unambiguously identified by genomic and proteomic sequencing as a DNA-binding protein HU. We report the amino acid sequence of HU as determined by sequencing the hup gene of four species (12 strains): C.

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Campylobacter jejuni has been isolated previously from market produce and has caused gastroenteritis outbreaks linked to produce. We have tested the ability of this human pathogen to utilize organic compounds that are present in leaf and root exudates and to survive in the plant environment under various conditions. Carbon utilization profiles revealed that C.

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