Mass cytometry as a tool in target validation and drug discovery.

Mass cytometry provides highly multiparametric data at a single cell level, coupling the specificity and sensitivity of time-of-flight mass spectrometry with the single-cell throughput of flow cytometry. It offers great value in interrogating the potentially heterogenous impact that a drug may have on a biological system, allowing an investigator to capture not just changes in cell behavior, but how these changes may differ between cell subtypes. In this chapter, we review the technical details of the platform as well as its limitations, before describing our approach to planning and running a mass cytometry experiment. A series of method modules, spanning the staining process through to data cleaning, are described that are then combined to create three separate experiments. The first experiment illustrates a core process in mass cytometry: the validation and titration of a metal-conjugated antibody reporter. The second experiment explores the impact of a kinase inhibitor on cell cycle and apoptosis pathways of a human myeloma cell line. And the third experiment exploits the multiparametric capability of mass cytometry, by exploring the differential expression changes in a transcription factor upon drug treatment across the cellular compartments of a peripheral blood mononuclear cell sample.

Pulmonary toxicity of instilled silver nanoparticles: influence of size, coating and rat strain.

Particle size and surface chemistry are potential determinants of silver nanoparticle (AgNP) respiratory toxicity that may also depend on the lung inflammatory state. We compared the effects of intratracheally-administered AgNPs (20 nm and 110 nm; polyvinylpyrrolidone (PVP) and citrate-capped; 0.1 mg/Kg) in Brown-Norway (BN) and Sprague-Dawley (SD) rats. In BN rats, there was both a neutrophilic and eosinophilic response, while in SD rats, there was a neutrophilic response at day 1, greatest for the 20 nm citrate-capped AgNPs. Eosinophilic cationic protein was increased in bronchoalveolar lavage (BAL) in BN and SD rats on day 1. BAL protein and malondialdehyde levels were increased in BN rats at 1 and 7 days, and BAL KC, CCL11 and IL-13 levels at day 1, with increased expression of CCL11 in lung tissue. Pulmonary resistance increased and compliance decreased at day 1, with persistence at day 7. The 20 nm, but not the 110 nm, AgNPs increased bronchial hyperresponsiveness on day 1, which continued at day 7 for the citrate-capped AgNPs only. The 20 nm versus the 110 nm size were more proinflammatory in terms of neutrophil influx, but there was little difference between the citrate-capped versus the PVP-capped AgNPs. AgNPs can induce pulmonary eosinophilic and neutrophilic inflammation with bronchial hyperresponsiveness, features characteristic of asthma.

Pharmacists making house calls: innovative role or overkill?

BACKGROUND: The Medication Management Program was established at the Fraser Health Authority in 2005, in response to evidence suggesting that having pharmacists provide care to patients in their homes after discharge from hospital could reduce subsequent utilization of health service resources. OBJECTIVE: To determine the effectiveness of the Medication Management Program in its first 2 years of operation. METHODS: For patients who had received a home visit by a pharmacist, the utilization of health services (admissions to hospital, physician office visits, and dispensed medications) in the year before the home visit was compared with utilization during the year after the intervention. The net cost of the program was also determined. RESULTS: In the first 2 years of the Medication Management Program (2005/2006 and 2006/2007), a total of 1171 patients received a home visit from a pharmacist. Of these, 836 (71%) were included in the before-and-after analysis. The median per-patient cost for utilization of health services was $11 014 lower in the year after the intervention than in the year preceding the intervention. After the costs of the program were taken into account, this resulted in a net median cost reduction of $3047.43 per patient. CONCLUSION: The Medication Management Program was effective as a clinical program in its first 2 years.

A note concerning acetate activation of peroxidative activity of catalases using 2,2'-azino-bis(3-ethylbenzthiazoline)-6-sulfonic acid as a substrate.

Beef liver catalases showed peroxidative activity using 2,2'-azino-bis-(3-ethylbenzthiazoline)-6-sulfonic acid as the electron donor and hydrogen peroxide as the acceptor at a pH of 5. This activity was not observed at pH 7. The reaction depended on acetate concentration, although succinate and propionate could partly replace the acetate as a catalyst. Other haem proteins also catalyzed a peroxidative effect. The reaction using syringaldazine or the coupling between dimethylaminobenzoic acid and 3-methyl-2-benzothiazolinone hydrazone was less effective and less sensitive. Evidence is presented that the reaction is associated with a conformational change of the catalase.