Detection of Plasmodium Infection by the illumigene Malaria Assay Compared to Reference Microscopy and Real-Time PCR.

Malaria is one of the leading causes of infectious disease in travelers returning from the tropics. The diagnosis of malaria is typically performed by examining Giemsa-stained thick and thin peripheral blood smears, which is time consuming, labor intensive, and requires high levels of proficiency. Alternatively, loop-mediated isothermal amplification (LAMP) is a new molecular method, which is rapid, sensitive, and requires less capital equipment and technological training. We conducted a retrospective study comparing two formats of a commercial LAMP assay (Meridian illumigene malaria [M] and malaria Plus [MP]) versus reference microscopy on archived blood specimens (n = 140) obtained from unique returning travelers suspected of having malaria. Discrepant results were resolved by either repeat testing or a laboratory developed ultrasensitive real-time PCR method. On initial testing, the Meridian illumigene M and MP kits had sensitivities of 97.3% (95% confidence interval [CI], 90.7 to 99.7%) and 100.0% (95.1 to 100.0%) and specificities of 93.8% (84.8 to 98.3%) and 91.5% (81.3 to 97.2%), respectively, versus reference microscopy. We project a significant cost reduction in low prevalence settings where malaria is not endemic with LAMP-based malaria screening given the excellent negative predictive value achieved with LAMP.

The Impact of Systematic Point-of-Care Ultrasound on Management of Patients in a Resource-Limited Setting.

Although target point-of-care (POC) ultrasonography has been shown to benefit patients in resource-limited settings, it is not clear whether a systematic POC ultrasound assessment in these settings can also lead to similar changes in patient management. A predefined systematic set of POC ultrasound scans were performed on inpatients at a tertiary referral hospital in Tanzania to see if this resulted in changes to patient management. Of the 55 patients scanned, an abnormality was detected in 75% (N = 41), and a change in patient management was recommended or implemented on the basis of POC ultrasound findings in 53% (N = 29). The main impact was earlier initiation of treatment due to more rapid and accurate diagnosis. Further research is warranted to determine whether systematic POC ultrasonography would result in improved patient outcomes in resource-limited settings.

Seniors' perspectives on care: a case study of the Alex Seniors health clinic, Calgary.

BACKGROUND: Primary care initiatives face an imperative to not only reduce barriers to care for their patients but also to uniquely accommodate the complex needs of at-risk patient populations. Patient-centered multidisciplinary care team models for primary care, like the Alex Seniors Clinic, are one approach for providing comprehensive care for marginalized seniors. The purpose of this qualitative study was to explore patient perspectives on the responsiveness of the Alex Seniors Clinic to their stated health needs. RESULTS: Themes reflected participants' perspectives on factors impacting their health needs as vulnerable seniors as well as on the measures that the Alex Seniors Clinic has taken to meet those needs. Factors impacting health included: the nature of their relationships to the physical environment in which they lived, the nature of the relationships they had to others in that environment, and independence and autonomy. Participants identified accessibility, respect and support, and advocacy as the ways in which the clinic was working to address those health needs. CONCLUSIONS: While respect and support, as well as advocacy, effectively addressed some patient needs, participants felt that accessibility problems continue to be health-related barriers for clinic patients. This may be due to the fact that issues of accessibility reflect larger community and social problems. Nevertheless, it is only through engaging the patient community for input on clinic approaches that an understanding can be gained of how closely a clinic's care goals are currently aligning with patient perspectives of the care and services they receive.

Expression, refolding, and initial structural characterization of the Y. pestis Ail outer membrane protein in lipids.

Ail is an outer membrane protein and virulence factor of Yersinia pestis, an extremely pathogenic, category A biothreat agent, responsible for precipitating massive human plague pandemics throughout history. Due to its key role in bacterial adhesion to host cells and bacterial resistance to host defense, Ail is a key target for anti-plague therapy. However, little information is available about the molecular aspects of its function and interactions with the human host, and the structure of Ail is not known. Here we describe the recombinant expression, purification, refolding, and sample preparation of Ail for solution and solid-state NMR structural studies in lipid micelles and lipid bilayers. The initial NMR and CD spectra show that Ail adopts a well-defined transmembrane ß-sheet conformation in lipids.

The mating pair stabilization protein, TraN, of the F plasmid is an outer-membrane protein with two regions that are important for its function in conjugation.

F plasmid TraN (602 aa, processed to 584 aa with 22 conserved cysteines), which is essential for F plasmid conjugation, is an outer-membrane protein involved in mating pair stabilization (MPS). Unlike R100 TraN, F TraN requires OmpA in the recipient cell for efficient MPS. The authors have identified three external loops (aa 172-187, 212-220 and 281-284) in the highly divergent region from aa 164 to aa 333 as candidates for interaction with OmpA. These loops were identified using both site-directed and random TnphoA/in mutagenesis to insert epitopes (31-aa or c-myc) into TraN and monitor their effect on sensitivity to external proteases and on mating ability. TraN is a hallmark protein of F-type IV secretion systems as demonstrated by blast searches of the databases. The C-terminal region is highly conserved and contains five of the six completely conserved cysteines. Mutation of these residues to serine demonstrated their importance in TraN function. TraN appears to require both intra- and intermolecular disulfide bond formation for its stability and structure as demonstrated by its instability in a dsbA mutant and its aberrant migration on SDS-polyacrylamide gels under non-reducing conditions or by cross-linking with bis(sulfosuccinimidyl)suberate (BS3). Thus, F TraN appears to have two domains: the N-terminal region is involved in OmpA interaction with OmpA during MPS; and the C-terminal region, which is rich in conserved cysteine residues, is essential for conjugation.