| 1. |
- Beal, Jacob, et al.
(författare)
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Robust estimation of bacterial cell count from optical density
- 2020
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Ingår i: Communications Biology. - : Springer Science and Business Media LLC. - 2399-3642. ; 3:1
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Tidskriftsartikel (refereegranskat)abstract
- Optical density (OD) is widely used to estimate the density of cells in liquid culture, but cannot be compared between instruments without a standardized calibration protocol and is challenging to relate to actual cell count. We address this with an interlaboratory study comparing three simple, low-cost, and highly accessible OD calibration protocols across 244 laboratories, applied to eight strains of constitutive GFP-expressing E. coli. Based on our results, we recommend calibrating OD to estimated cell count using serial dilution of silica microspheres, which produces highly precise calibration (95.5% of residuals <1.2-fold), is easily assessed for quality control, also assesses instrument effective linear range, and can be combined with fluorescence calibration to obtain units of Molecules of Equivalent Fluorescein (MEFL) per cell, allowing direct comparison and data fusion with flow cytometry measurements: in our study, fluorescence per cell measurements showed only a 1.07-fold mean difference between plate reader and flow cytometry data.
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| 2. |
- Parma, Valentina, et al.
(författare)
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More Than Smell—COVID-19 Is Associated With Severe Impairment of Smell, Taste, and Chemesthesis
- 2020
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Ingår i: Chemical Senses. - : Oxford University Press (OUP). - 0379-864X .- 1464-3553. ; 45:7, s. 609-622
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Tidskriftsartikel (refereegranskat)abstract
- Recent anecdotal and scientific reports have provided evidence of a link between COVID-19 and chemosensory impairments, such as anosmia. However, these reports have downplayed or failed to distinguish potential effects on taste, ignored chemesthesis, and generally lacked quantitative measurements. Here, we report the development, implementation, and initial results of a multilingual, international questionnaire to assess self-reported quantity and quality of perception in 3 distinct chemosensory modalities (smell, taste, and chemesthesis) before and during COVID-19. In the first 11 days after questionnaire launch, 4039 participants (2913 women, 1118 men, and 8 others, aged 19–79) reported a COVID-19 diagnosis either via laboratory tests or clinical assessment. Importantly, smell, taste, and chemesthetic function were each significantly reduced compared to their status before the disease. Difference scores (maximum possible change ±100) revealed a mean reduction of smell (−79.7 ± 28.7, mean ± standard deviation), taste (−69.0 ± 32.6), and chemesthetic (−37.3 ± 36.2) function during COVID-19. Qualitative changes in olfactory ability (parosmia and phantosmia) were relatively rare and correlated with smell loss. Importantly, perceived nasal obstruction did not account for smell loss. Furthermore, chemosensory impairments were similar between participants in the laboratory test and clinical assessment groups. These results show that COVID-19-associated chemosensory impairment is not limited to smell but also affects taste and chemesthesis. The multimodal impact of COVID-19 and the lack of perceived nasal obstruction suggest that severe acute respiratory syndrome coronavirus strain 2 (SARS-CoV-2) infection may disrupt sensory-neural mechanisms.
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| 3. |
- White, Marc, et al.
(författare)
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Planning, Implementing and Evaluating Successful Workplace Interventions for Psychologically Healthy and Productive Workplaces : A Pattern Analysis of 57 Systematic Reviews
- 2020
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- Mental health in the workplace is a key topic in British Columbia, across Canada and internationally with a growing focus on the importance of creating and sustaining safe, healthy, productive and inclusive workplaces. This stakeholder-centred best evidence-based synthesis of systematic reviews searched Medline, Embase, Cochrane Database of Systematic Reviews, Database of Abstracts of Reviews of Effectiveness, CINAHL, PsycINFO, TRIP, REHABDATA (NARIC), REHAB+ (McMaster), and Health-evidence.ca (McMaster) published between January 1, 2000 and February 2016 to identify interventions that addressed: mental health symptomatology (depression, anxiety, PTSD, etc.), job control, job demands, social support, stress management, and wellness (health promotion). Following deduplication 5,646 citations were reviewed by two or more independent reviewers. Following title and abstract review, 168 full text articles were reviewed against inclusion/exclusion criteria, resulting in 57 systematic reviews being included. Based on findings and trend analysis, the academic-stakeholder team proposed a framework for planning, implementing and evaluating interventions to mitigate psychosocial hazards in the workplace. Due to low quality evidence and experimental pre and post design of many studies recommendations should be considered with some caution noting the need for more rigorous monitoring of their implementation.
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