Neutrophil extracellular traps (NETs) are webs of DNA covered with antimicrobial molecules that constitute a newly described killing mechanism in innate immune defense. Previous publications reported that NETs take up to 3–4 h to form via an oxidant-dependent event that requires lytic death of neutrophils. In this study, we describe neutrophils responding uniquely to Staphylococcus aureus via a novel process of NET formation that did not require neutrophil lysis or even breach of the plasma membrane. The multilobular nucleus rapidly became rounded and condensed. During this process, we observed the separation of the inner and outer nuclear membranes and budding of vesicles, and the separated membranes and vesicles were filled with nuclear DNA. The vesicles were extruded intact into the extracellular space where they ruptured, and the chromatin was released. This entire process occurred via a unique, very rapid (5–60 min), oxidant-independent mechanism. Mitochondrial DNA constituted very little if any of these NETs. They did have a limited amount of proteolytic activity and were able to kill S. aureus. With time, the nuclear envelope ruptured, and DNA filled the cytoplasm presumably for later lytic NET production, but this was distinct from the vesicular release mechanism. Panton–Valentine leukocidin, autolysin, and a lipase were identified in supernatants with NET-inducing activity, but Panton–Valentine leukocidin was the dominant NET inducer. We describe a new mechanism of NET release that is very rapid and contributes to trapping and killing of S. aureus.

We describe a patient with mycetoma or Madura foot, in RESUMO Descrevemos um paciente com micetoma ou maduromicose de pé, no que colorações histopatológicos de osso e de culturas superficiais sugeriram três organismos diferentes, incluindo espécies de Nocardia como causador. Os critérios de diagnóstico dos organismos, a diferenciação entre colonizador e patógeno, e a significância das infecções mistas são discutidos.Palavras-chaves: Micetoma. Maduromicose de pé. Colonização.

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Background: Infectious diseases, including infections with helminths, can initially present similarly to malignancies. The goal of the article is to review reports of helminthic infections that are initially diagnosed as malignancy. Methodology: The database PubMed was searched for English language references published as of July 2009. Results: The following published case reports and case series, mainly from Asia and Africa, were identified: Nematodes: 8 publications (1 patient with Angiostrongylus cantonensis, 2 Stronglyloides stercoralis, 1 Toxocara species, 1 Dioctophyma renale, 1 Ascaris species, 1 Gnathostoma spinigerum, 1 Dirofilaria repens); Trematodes: 7 publications (46 patients with Schistosoma species, 2 Fasciola hepatica, 1 Paragonimus westermani); Cestodes: 6 publications (10 patients with Echinococcus species, 1 Sparganum mansoni). Conclusion: To avoid unnecessary investigations and treatment, physicians should be aware when diagnosing patients from Asia or Africa that a large number of helminthic infections can present similar to malignancies.