Catalytic activation of extracellular signal-regulated kinases induces cyclin D1 expression in primary tracheal myocytes

We have demonstrated that extracellular signal-regulated kinases (ERKs) and cyclin D1 are required for bovine tracheal myocyte DNA synthesis. We hypothesized that catalytic activation by ERKs may regulate cyclin D1 expression in these cells. To test this hypothesis, we examined the effects of two inhibitors of ERKs and two reagents that increase the level of activated ERKs on cyclin D1 protein abundance and promoter activity. ERK activity was inhibited either by PD98059, a synthetic inhibitor of mitogen-activated protein kinase (MAPK)/ERK kinase (MEK), the upstream signaling intermediate required and sufficient for ERK activation, or by transient transfection with a dominant-negative mutant of MEK1 (MEK-2A). The level of activated ERKs was increased by transient transfection with either a constitutively active form of MEK1 (MEK-2E) or wild-type ERK2 (MAPKwt). Cyclin D1 expression was assessed either by immunoblot or cotransfection with the full-length cyclin D1 promoter subcloned into a luciferase reporter. We found that pretreatment of bovine tracheal myocytes with PD98059 significantly attenuated platelet- derived growth factor (PDGF)-induced cyclin D1 protein abundance. Furthermore, transfection with MEK-2A reduced PDGF-induced cyclin D1 promoter activity. Finally, transfection with either MEK-2E or MAPKwt induced cyclin D1 promoter activity in the absence of growth factor treatment. We conclude that catalytic activation of ERKs regulates cyclin D1 expression in airway smooth-muscle cells.     

Building a successful risk-based competency assessment model

The requirement to verify and ensure the competency of staff members to perform their assigned duties is here to stay. This article describes a model for decision making about competency assessment frequency. Implementation of the model should be accompanied by a systematic review of learning needs and performance improvement data. Education sessions designed to address identified learning needs or to support performance improvement activities should occur before or concurrent with competency assessment. The result is a cost-effective, efficient use of resources to accomplish the goal of ongoing assessment and improvement of staff competency. When staff member competency improves, the likelihood of a positive patient outcome increases. Our model provides a structured, defensible mechanism to link competency assessment with improvements in patient care quality.     

Gold nanosphere-antibody conjugates for hyperthermal therapeutic applications

Gold nanoparticles can be conjugated with antibodies or other proteins, and the resulting composite particles will selectively attach to various kinds of biological material. Although exploitation of this for staining microscopy specimens is well known, there has recently been interest in attaching gold nanoparticles tolive cells for therapeutic reasons. One motivation is that gold nanoparticles display a strong plasmon resonance with light, which can be exploited in principle for an ‘in vivo’ photothermal therapy. The treatment of cancer by this technique has recently received attention by others, but here we show how gold nanoparticlebased therapies can be developed to target live macrophage cells. We have employed ‘active targeting’, a scheme in which gold nanoparticles are functionalised with an antibody specific to the target macrophage cell. We describe how to prepare the conjugated particles, demonstrate that they will selectively attach ‘in vitro’ to their target macrophage cell but not to a non-target cell type and show that their presence renders the target cell susceptible to destruction by a low power laser.     

Immunotherapy and experimental approaches for metastatic melanoma

This article reviews the clinical investigations involving recombinant cytokines (either alone or in combination with adoptive immunotherapy, toxicity reduction agents, or cytotoxic chemotherapy), vaccines, monoclonal antibodies or antibody conjugates, and gene therapy. These various approaches are reviewed for their current and potential roles in curing metastatic melanoma.