Collectively, this in vitro study provides insights into action of palladium and platinum complexes and demonstrates the potential use of these compounds, and in particular complex 3, in the development of new anticancer agents.

Streptococcus pneumoniae is a major cause of pneumonia, bacteremia, and meningitis, especially among adults infected with the human immunodeficiency virus (HIV). Alveolar macrophages (AMs) are critical components of cellular defense against bacterial infection and are both infected and affected by HIV. In this study, AMs obtained at bronchoscopy from 44 Malawian adults (24 HIV positive and 20 HIV negative) were exposed in vitro to opsonized S. pneumoniae and coagulase-negative staphylococci. AMs from HIV-positive and -negative volunteers showed no significant difference in binding to or internalization of either S. pneumoniae or coagulase-negative staphylococci. In HIV-positive subjects, the presence of detectable HIV in lung fluid was not associated with AM impairment. AMs from HIV-infected adults did not exhibit impaired pneumococcal phagocytosis in the assay used. This suggests that an alternative mechanism of susceptibility is operating in these individuals.

Streptococcus pneumoniae infections can be prevented by using new conjugate vaccines, but these vaccines have limited serogroup coverage. We report the first serogrouping data from carried and invasive isolates obtained from children and adults in Malawi. The 7-valent vaccine would cover 41% of invasive isolates from children and 25% from adults. A 9-valent vaccine, including types 1 and 5, would cover 66% of invasive isolates from children and 55% from adults.

We describe here a technical improvement of an established colorimetric method used to detect and measure the occurrence of apoptosis in mammalian cells during in vitro cell culture. This assay uses an anionic halogenated fluorescein dye that is taken up by apoptotic cells at the stage of phosphatidylserine externalization. We demonstrate that apoptotic cells stained with this dye can be detected by flow cytometric analysis. Furthermore, we show that the modified method compares well with the standard annexin-V-based apoptosis assay and that it is significantly more cost-effective than the annexin-V assay.

Reduced interleukin-8 production may result in decreased neutrophil recruitment, and hence increased susceptibility to pneumococcal infection in HIV-infected subjects.

No abstract