| 1. |
|
|
| 2. |
- Beal, Jacob, et al.
(författare)
-
Robust estimation of bacterial cell count from optical density
- 2020
-
Ingår i: Communications Biology. - : Springer Science and Business Media LLC. - 2399-3642. ; 3:1
-
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.
|
|
| 3. |
-
- 2019
-
Tidskriftsartikel (refereegranskat)
|
|
| 4. |
- Chen, Zhen, et al.
(författare)
-
Design, Synthesis, and Evaluation of Reversible and Irreversible Monoacylglycerol Lipase Positron Emission Tomography (PET) Tracers Using a "Tail Switching" Strategy on a Piperazinyl Azetidine Skeleton
- 2019
-
Ingår i: Journal of Medicinal Chemistry. - : American Chemical Society (ACS). - 0022-2623 .- 1520-4804. ; 62:7, s. 3336-3353
-
Tidskriftsartikel (refereegranskat)abstract
- Monoacylglycerol lipase (MAGL) is a senile hydrolase that degrades 2-arachidonoylglycerol (2-AG) in the endocannabinoid system (eCB). Selective inhibition of MAGL has emerged as a potential therapeutic approach for the treatment of diverse pathological conditions, including chronic pain, inflammation, cancer, and neurodegeneration. Herein, we disclose a novel array of reversible and irreversible MAGL inhibitors by means of "tail switching" on a piperazinyl azetidine scaffold. We developed a lead irreversible-binding MAGL inhibitor 8 and reversible-binding compounds 17 and 37, which are amenable for radiolabeling with C-11 or F-18. [C-11]8 ([C-11]MAGL-2-11) exhibited high brain uptake and excellent binding specificity in the brain toward MAGL. Reversible radioligands [C-11]17 ([C-11]PAD) and [F-18]37 ([F-18]MAGL-4-11) also demonstrated excellent in vivo binding specificity toward MAGL in peripheral organs. This work may pave the way for the development of MAGL-targeted positron emission tomography tracers with tunability in reversible and irreversible binding mechanisms.
|
|
| 5. |
- Jin, Han, et al.
(författare)
-
A Mobile-Based High Sensitivity On-Field Organophosphorus Compounds Detecting System for IoT-Based Food Safety Tracking
- 2017
-
Ingår i: Journal of Sensors. - : Hindawi Publishing Corporation. - 1687-725X .- 1687-7268.
-
Tidskriftsartikel (refereegranskat)abstract
- A mobile-based high sensitivity absorptiometer is presented to detect organophosphorus (OP) compounds for Internet-of-Things based food safety tracking. This instrument consists of a customized sensor front-end chip, LED-based light source, low power wireless link, and coin battery, along with a sample holder packaged in a recycled format. The sensor front-end integrates optical sensor, capacitive transimpedance amplifier, and a folded-reference pulse width modulator in a single chip fabricated in a 0.18 mu m 1-poly 5-metal CMOS process and has input optical power dynamic range of 71 dB, sensitivity of 3.6 nW/cm(2) (0.77 pA), and power consumption of 14.5 mu W. Enabled by this high sensitivity sensor front-end chip, the proposed absorptiometer has a small size of 96 cm(3), with features including on-field detection and wireless communication with a mobile. OP compound detection experiments of the handheld system demonstrate a limit of detection (LOD) of 0.4 mu mol/L, comparable to that of a commercial spectrophotometer. Meanwhile, an android-based application (APP) is presented which makes the absorptiometer access to the Internet-of-Things (IoT).
|
|
| 6. |
|
|
| 7. |
- Schuettpelz, Eric, et al.
(författare)
-
A community-derived classification for extant lycophytes and ferns
- 2016
-
Ingår i: Journal of Systematics and Evolution. - : Wiley. - 1674-4918 .- 1759-6831. ; 54:6, s. 563-603
-
Tidskriftsartikel (refereegranskat)abstract
- Phylogeny has long informed pteridophyte classification. As our ability to infer evolutionary trees has improved, classifications aimed at recognizing natural groups have become increasingly predictive and stable. Here, we provide a modern, comprehensive classification for lycophytes and ferns, down to the genus level, utilizing a community-based approach. We use monophyly as the primary criterion for the recognition of taxa, but also aim to preserve existing taxa and circumscriptions that are both widely accepted and consistent with our understanding of pteridophyte phylogeny. In total, this classification treats an estimated 11 916 species in 337 genera, 51 families, 14 orders, and two classes. This classification is not intended as the final word on lycophyte and fern taxonomy, but rather a summary statement of current hypotheses, derived from the best available data and shaped by those most familiar with the plants in question. We hope that it will serve as a resource for those wanting references to the recent literature on pteridophyte phylogeny and classification, a framework for guiding future investigations, and a stimulus to further discourse.
|
|
| 8. |
|
|
| 9. |
|
|
| 10. |
- Bergman, Birgitta, et al.
(författare)
-
The cyanobacterium–Azolla symbiosis: Interactions and cell differentiation
- 2007
-
Ingår i: Abstracts of the Annual Main Meeting of the Society for Experimental Biology, Glasgow, Scotland, 31st March - 4th April, 2007. - : Elsevier BV.
-
Konferensbidrag (populärvet., debatt m.m.)abstract
- Selected cyanobacteria form stable nitrogen-fixing symbioses with diverse eukaryotes. The water-fern Azolla carries a nitrogen-fixing cyanobacterium (cyanobiont) in its leaves and shows a pronounced intimacy between its partners. It is the only perpetual N2-fixing symbiosis, i.e. the cyanobiont is vertically transmitted in sporocarps between plant generations. The cyanobiont also seems incapable of independent growth which may suggest gene loss and that the symbiosis is on its way to evolve into a N2-fixing plant. Proteomic analyses of the cyanobiont (2-D coupled to MS) resulted in an identification of about 79% of proteins analysed. Processes upregulated were related to energy production, nitrogen and carbon metabolism and stress, while photosynthesis and metabolic turnover rates were downregulated, stressing a slow heterotrophic mode of growth, high heterocyst frequencies and nitrogen-fixing capacities. Peptide mass spectra of NifH demonstrated the presence of a 300–400 Da protein modification localized to a 13 amino acid sequence. Additionally, a short phylogenetic distance between the cyanobiont and some sequenced cyanobacteria (Section IV) and the database hits of the proteins identified by proteomics, together suggest that the Azolla cyanobiont may represent a novel cyanobacterial genus. The genome of the cyanobiont will be sequenced in 2007 (DOE/JGI, USA).
|
|
