Ultrastructure of Legionella pneumophila.

Eleven lung samples positive for Legionnaires' disease, 12 strains of Legionella pneumophila cultured on various bacteriological media, and one strain growth in the yolk sac of fertile hens' eggs were examined by negative staining, thin sectioning, and scanning electron microscopy. All organisms studied were ultrastructurally similar irrespective of strain, source, or method of cultivation, presenting mainly as short rods, 0.6 x 1.5 micrometer, with tapered ends, though long forms and filaments were also evident. In this they resembled typical Gram-negative organisms. Division was by non-septate binary fission, and the cell wall was composed of two triple-unit membranes with morphological evidence of a peptidoglycan layer. The bacterial cytoplasm was rich in ribosomes and nuclear elements and often contained vacuoles. No acid polysaccharides or bacterial appendages were detected surrounding the organisms. In lung tissue and yolk sac membranes, the organisms replicated within the cytoplasm of infected cells and in the intercellular spaces and were specifically identified in thin sections by immunoferritin techniques.     

Can old drugs learn new tricks? Achieving registration and public subsidy listing for off-patent medicines with novel therapeutic applications

With the increasing costs of drug development, repurposing of low-cost medicines for new indications has never been more important. However, there are multiple barriers to repurposing, particularly for off-patent medicines, and limited incentives for the pharmaceutical industry to sponsor registration and public subsidy listing. Here, we explore these barriers and their consequences and provide examples of successful repurposing strategies.     

Snoring, daytime sleepiness and stroke: a case-control study of first-ever stroke

Previous reports have shown an association between snoring and stroke but it is not clear whether this reflects confounding factors nor whether the association is attributable to obstructive sleep apnoea (OSA). We performed a case-control study of 181 patients admitted to hospital with first-ever stroke and community control subjects matched individually for age, sex and general practitioner. Subjects were interviewed with a structured questionnaire to identify snoring, daytime sleepiness and stroke risk factors. The association between snoring alone and stroke was not statistically significant: odds ratio (95% CI) 1.44 (0.88, 2.41). Daytime sleepiness was, however, significantly associated with stroke: odds ratio 3.07 (1.65, 6.08). Multiple logistic regression showed that hypertension, current smoking, taking alcohol regularly (negatively) and a higher Epworth sleepiness score were independently associated with stroke. The results suggest that the previously reported association between 'simple' snoring and stroke might have been due to poor controlling for confounding variables. Our study suggests an association with greater sleepiness prestroke, the cause of which is unclear, although OSA is a possible candidate.     

Acne Knowledge of Hispanic Parents of Teenagers with Mild to Moderate Acne

We performed a cross‐sectional study of Hispanic and non‐Hispanic parents of children with acne using a survey designed to determine their level of awareness of acne and its treatment; 82% of Hispanic parents and 40% of non‐Hispanic parents agreed that a health care provider should treat mild acne (p < 0.001). Hispanic parents of adolescents with acne agreed more frequently than non‐Hispanic parents that children with mild and moderate acne should be taken to a health care provider for treatment, but they tended not to visit health care providers. Future studies should aim to determine the reasons for this discrepancy, after which culturally sensitive educational programs can be developed to address this disparity.     

The Role of Sialic Acid in Opsonin-Dependent and Opsonin-Independent Adhesion of Listeria monocytogenes to Murine Peritoneal Macrophages

The adhesion of listeriae to host cells employs mechanisms which are complex and not well understood. Listeria monocytogenes is a facultative intracellular pathogen responsible for meningoencephalitis, septicemia, and abortion in susceptible and immunocompromised individuals. Subsequent to colonization and penetration of the gut epithelium, the organism attaches to resident macrophages and replicates intracellularly, thus evading the humoral immune system of the infected host. The focus of these studies was to investigate the attachment of the organism to murine peritoneal macrophages in an opsonin-dependent and opsonin-independent fashion. Assessment of competitive binding experiments by immunofluorescence and enzyme-linked immunosorbent assays showed that adhesion of the organism to macrophages in the presence or absence of opsonins was inhibited (90%) by N-acetylneuraminic acid (NAcNeu). In addition, the lectin from Maackia amurensis, with affinity for NAcNeu-α(2,3)galactose, blocked binding of L. monocytogenes to host cells. Oxidation of the surface carbohydrates on the organism by using sodium metaperiodate resulted in a dose-dependent reduction (up to 98%) in adherence to macrophages. Monoclonal antibody to complement receptor 3 did not prevent listeriae from binding to mouse macrophages or from replicating within the infected cells whether or not normal mouse serum was present. Based on our results, we propose the involvement of NAcNeu, a member of the sialic acid group, in the attachment of L. monocytogenes to permissive murine macrophages.     

Activation of the human delta-globin gene promoter in primary adult erythroid cells

Restoration of the CCAAT box or insertion of an erythroid Krüppel-like factor (EKLF) binding site in the delta promoter activates its expression in several erythroid cell lines. We extended these studies using a novel primary human adult erythroid cell ( h AEC) system to investigate these effects at the late erythroblast stage. Restoration of the CCAAT box at −70 bp, or insertion of an EKLF binding site at −85 bp or −95 bp in the promoter significantly increased delta globin gene expression in h AEC. Our results demonstrate that the altered CCAAT box (CCAAC) and the lack of an EKLF binding site in δ-globin contribute to its low level of expression in the h AEC model as well.     

Getting to Know the Competition: A Content Analysis of Publicly and Corporate Funded Physical Activity Advertisements

The authors examine how crime and violence is reported and framed by the Los Angeles Times . Using a public health perspective, we examine whether health-oriented variables, such as causal factors and societal effects of crimes, are present in crime news stories. The classic stereotyping of crime and violence framing is strongly present in the Times . We discuss what changes would be useful to provide news consumers with a more accurate picture of crime in their community.     

Current trends in U.S. cardiology practice

Over the last six years, the practice of cardiology in the U.S. has experienced a substantial transition from independent practice to practices integrated within hospital systems. This change has been driven by major economic factors that have largely been determined by the federal government. Meanwhile, cardiologists? salaries and the demand for new cardiologists have remained stable. Best practices have embraced this new partnership with hospital systems to improve quality, cost, and access to cardiovascular care.     

Carcinoma of the Breast

A great deal of controversy surrounds the question of the effectiveness of treatment of breast carcinoma, particularly radical surgical procedures in early cases.

The results of simple mastectomy followed by radiotherapy are compared with those of radical surgery in two series of cases, in Edinburgh and at the Mayo Clinic, respectively; despite the many variables involved in such a comparison, the figures are of interest because of their similarity.

Endocrine therapy in metastasizing breast cancer has profoundly altered malignant growth in some cases. Hypophysectomy is gaining favor and appears to be superseding adrenalectomy.