The use of UV-C radiation for terminal disinfection of pathogenic Gram-negative rods: a pilot study.

In this controlled study, we found that exposure to ultraviolet-C (UV-C) radiation was able to arrest the growth of selected pathogenic enteric and nonfermenting Gram-negative rods. Further studies are needed to confirm the clinical efficacy and determine optimal implementation strategies for utilizing UV-C terminal disinfection.

VA-Wide, Multicenter Verification Study of the Cepheid Xpert SARS-CoV-2 Assay.

Early in the Severe Acute Respiratory Syndrome Coronavirus 2 pandemic, there was a progressive increase in diagnostic demands that developed within a relatively short period of time. On February 4, 2020, the Secretary of Health and Human Services issued the Emergency Use Authorization for in vitro diagnostics assays for the Severe Acute Respiratory Syndrome Coronavirus 2 virus. Subsequently, multiple assays were approved under the Emergency Use Authorization, including the Cepheid Xpert SARS-CoV-2 assay. Presented here is a description of the nationally coordinated verification study of the Cepheid assay that was performed within the Veteran's Affairs Health System. This coordinated study helped to expedite the verification process for a majority of the Veteran's Affairs system labs, preserved precious system resources, and highlighted the power of a national medical system in response to an emergency.

Method for measurement of serum copper, zinc and selenium using total reflection X-ray fluorescence spectroscopy on the PICOFOX analyser: Validation and comparison with atomic absorption spectroscopy and inductively coupled plasma mass spectrometry.

BACKGROUND: Total reflection X-ray fluorescence is a comparably new method for the measurement of trace elements in biological samples. METHODS: Results obtained by total reflection X-ray fluorescence were compared to atomic absorption spectroscopy for Cu and Zn and inductively coupled plasma mass spectrometry for Cu, Zn and Se in patient serum. The total reflection X-ray fluorescence assay was characterized for accuracy; recovery; intra- and inter-assay imprecision (using patients' samples, external quality assurance and quality control materials); limit of blank; limit of detection; linearity; interference and stability of prepared samples. RESULTS: Minimal sample preparation is required for total reflection X-ray fluorescence and simultaneous multi-elemental analysis is possible in clinical samples. There was a small positive bias for Cu and Zn measurements using total reflection X-ray fluorescence compared to atomic absorption spectroscopy and inductively coupled plasma mass spectrometry and a significant negative bias for Se measurements by total reflection X-ray fluorescence relative to inductively coupled plasma mass spectrometry. Recovery, imprecision and linearity were acceptable. The limit of detection was shown to be 1.2 µmol/L for serum Cu, 1.8 µmol/L for serum Zn and 0.2 µmol/L for serum Se. CONCLUSIONS: Measurement of Cu and Zn in serum samples using total reflection X-ray fluorescence would be a viable alternative to atomic absorption spectroscopy or inductively coupled plasma mass spectrometry. The volatility of some Se compounds results in lower Se results being reported using total reflection X-ray fluorescence and further work would be necessary to identify whether total reflection X-ray fluorescence has an acceptable clinical sensitivity and specificity for the assessment of Se deficiency. Measurement of copper, zinc and selenium on whole blood samples is possible using total reflection X-ray fluorescence which may provide a more accurate assessment of trace element deficiency for patients with an acute phase response.