Different forms of heavy metals affect biochemical systems in characteristic ways that cannot be detected with typical metal analysis methods like atomic absorption spectrometry. Further, using living systems to analyze interaction of heavy metals with biochemical systems can be laborious and unreliable. To generate a reliable easy-to-use biologically-based biosensor system, the entire human metallothionein-II (MT-II) gene was incorporated into a plasmid (pUC57-MT) easily replicated in Escherichia coli.
View Article and Find Full Text PDFVaricella-zoster virus (VZV) infections have declined in many industrialized countries due to vaccination with the attenuated Oka strain virus. Rare cases of severe, disseminated vaccine-strain VZV infection have occurred in the immunocompromised, although rarely in HIV-infected persons. We describe a man with previously-undiagnosed human immunodeficiency virus (HIV) infection who received VZV vaccination and subsequently presented to a combat hospital in Afghanistan with disseminated varicella, respiratory failure, and sepsis.
View Article and Find Full Text PDFUse of engineered metal oxide nanoparticles in a plethora of biological applications and custom products has warned about some possible dose-dependent cytotoxic effects. Macrophages are key components of the innate immune system used to study possible toxic effects and internalization of different nanoparticulate materials. In this work, ultra-high resolution field emission scanning electron microscopy (FE-SEM) was used to offer new insights into the dynamical processes of interaction of nanomaterials with macrophage cells dosed with different concentrations of metal oxide nanoparticles (CeO(2), TiO(2) and ZnO).
View Article and Find Full Text PDFGroup A streptococcus (GAS) depends on a hyaluronic acid (HA) capsule to evade phagocytosis and to interact with epithelial cells. Paradoxically, GAS also produces hyaluronidase (Hyl), an enzyme that cleaves HA. A common assumption is that Hyl digests structurally identical HA in human tissue to promote bacterial spread.
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