Oxidized low-density lipoprotein (oxLDL) is considered one of the principal effectors of atherogenesis. To explore mechanisms by which oxLDL affects human mononuclear phagocytes, we incubated these cells in medium containing oxLDL, acetylated LDL (acLDL), or native LDL, or on surfaces coated with these native and modified lipoproteins. The presence of soluble oxLDL, acLDL, or native LDL in the medium did not stimulate H2O2 secretion by macrophages. In contrast, macrophages adherent to surfaces coated with oxLDL secreted three- to fourfold more H2O2 than macrophages adherent to surfaces coated with acLDL or native LDL. Freshly isolated blood monocytes secreted little H2O2 regardless of the substrate on which they were plated. H2O2 secretion was maximal in cells maintained for 4–6 d in culture before plating on oxLDL-coated surfaces. Fucoidan, a known ligand of class A macrophage scavenger receptors (MSR-A), significantly reduced macrophage adhesion to surfaces coated with oxLDL or acLDL. Monoclonal antibody SMO, which blocks oxLDL binding to CD36, did not inhibit adhesion of macrophages to oxLDL-coated surfaces but markedly reduced H2O2 secretion by these cells. These studies show that MSR-A is primarily responsible for adhesion of macrophages to oxLDL-coated surfaces, that CD36 signals H2O2 secretion by macrophages adherent to these surfaces, and that substrate-bound, but not soluble, oxLDL stimulates H2O2 secretion by macrophages.

In this article, we give an overview of new technologies for the diagnosis of tuberculosis (TB) and drug resistance, consider their advantages over existing methodologies, broad issues of cost, cost-effectiveness and programmatic implementation, and their clinical as well as public health impact, focusing on the industrialized world. Molecular nucleic-acid amplification diagnostic systems have high specificity for TB diagnosis (and rifampicin resistance) but sensitivity for TB detection is more variable. Nevertheless, it is possible to diagnose TB and rifampicin resistance within a day and commercial automated systems make this possible with minimal training. Although studies are limited, these systems appear to be cost-effective. Most of these tools are of value clinically and for public health use. For example, whole genome sequencing of Mycobacterium tuberculosis offers a powerful new approach to the identification of drug resistance and to map transmission at a community and population level.

PurposeThe clinical presentation and epidemiology for patients with enteric fever at two hospitals in East London during 2007–2012 is described with the aim to identify preventive opportunities and to reduce the cost of treatment.MethodsA retrospective analysis of case notes from patients admitted with enteric fever during 2007 to 2012 with a microbiologically confirmed diagnosis was undertaken. Details on clinical presentation, travel history, demographic data, laboratory parameters, treatment, patient outcome and vaccination status were collected.ResultsClinical case notes were available for 98/129 (76%) patients including 69 Salmonella enterica serovar Typhi (S. Typhi) and 29 Salmonella enterica serovar Paratyphi (S. Paratyphi). Thirty-four patients (35%) were discharged from emergency medicine without a diagnosis of enteric fever and then readmitted after positive blood cultures. Seventy-one of the 98 patients (72%) were UK residents who had travelled abroad, 23 (23%) were foreign visitors/new entrants to the UK and four (4%) had not travelled abroad. Enteric fever was not considered in the initial differential diagnosis for 48/98 (49%) cases. The median length of hospital stay was 7 days (range 0–57 days). The total cost of bed days for managing enteric fever was £454,000 in the two hospitals (mean £75,666/year). Median time to clinical resolution was five days (range 1–20). Seven of 98 (7%) patients were readmitted with relapsed or continued infection. Six of the 71 (8%) patients had received typhoid vaccination, 34 (48%) patients had not received vaccination, and for 31 cases (44%) vaccination status was unknown.ConclusionsFurther interventions regarding education and vaccination of travellers and recognition of the condition by emergency medicine clinicians in travellers to South Asia is required.