Rapid Identification and Analysis of Ochratoxin-A in Food and Agricultural Soil Samples Using a Novel Semi-Automated In-Syringe Based Fast Mycotoxin Extraction (FaMEx) Technique Coupled with UHPLC-MS/MS.

In this work, a fast mycotoxin extraction (FaMEx) technique was developed for the rapid identification and quantification of carcinogenic ochratoxin-A (OTA) in food (coffee and tea) and agricultural soil samples using ultra-high-performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) detection. The FaMEx technique advancement is based on two plastic syringes integrated setup for rapid extraction and its subsequent controlled clean-up process. In the extraction process, a 0.25-g sample and extraction solvent were added to the first syringe barrel for the vortex-based extraction. Then, the extraction syringe was connected to a clean-up syringe (pre-packed with C18, activated carbon, and MgSO4) with a syringe filter. Afterward, the whole set-up was placed in an automated programmable mechanical set-up for controlled elution. To enhance FaMEx technology performance, the various influencing sample pretreatment parameters were optimized. Furthermore, the developed FaMEx method indicated excellent linearity (0.9998 and 0.9996 for coffee/tea and soil) with highly sensitive detection (0.30 and 0.29 ng/mL for coffee/tea and soil) and quantification limits (1.0 and 0.96 for coffee/tea and soil), which is lower than the toxicity limit compliant with the European Union regulation for OTA (5 ng/g). The method showed acceptable relative recovery (84.48 to 100.59%) with <7.34% of relative standard deviation for evaluated real samples, and the matrix effects were calculated as <-13.77% for coffee/tea and -9.7 for soil samples. The obtained results revealed that the developed semi-automated FaMEx/UHPLC-MS/MS technique is easy, fast, low-cost, sensitive, and precise for mycotoxin detection in food and environmental samples.

Effects of Lighting Interventions to Improve Sleepiness in Night-Shift Workers: A Systematic Review and Meta-Analysis.

Shift work disrupts an otherwise normal circadian rhythm, which may result in sleepiness among night-shift workers. Artificial light has been shown to alter the light-dark cycle of shift workers and reset or phase shift the biological clock, improving nighttime alertness in workers. However, the effect of light therapy on improving sleepiness in nighttime workers has not been effectively confirmed in nursing clinical studies, and it is worth using relevant studies to provide the best evidence in any clinical setting. Systematic review and meta-analysis were used. The study was performed using PRISMA. Academic Search Complete, Embase, MEDLINE, the Cochrane Library, and CINAHL were searched, from the inception of each database to 27 December 2021. The Cochrane risk of bias tool was used to assess the methodological quality of each study. Standardized mean differences (SMDs) with 95% confidence intervals (CIs) were synthesized using a random-effects model to assess the efficacy of lighting intervention to improve sleepiness in night-shift workers. Sensitivity analysis followed by subgroup analysis was employed to examine heterogeneity. The meta-analysis was performed using Review Manager 5.4.1 software. A total of 14 studies from 7 countries were included. The overall result shows that lighting interventions significantly improved sleepiness. Further, the blue-enriched white light with a color temperature greater than 5000 Kelvin was effective in improving sleepiness of night-shift workers. This study unveils the emergent knowledge that light interventions with blue-enriched white were effective in improving sleepiness for night-shift workers, including nurses. This finding can be applied to ensure patient safety, reduce accidents, and improve work efficiency and job satisfaction. Nurses constitute the largest health professional workforce. We suggest that hospitals can insert blue-enriched white light equipment for night-shift healthcare providers. Several evidence-based suggestions are made for further consideration.

Effect of dermal phthalate levels on lung function tests in residential area near a petrochemical complex.

Phthalates can leach into indoor and outdoor airborne particulate matter and dust, which can then be ingested or absorbed and induce lung injury. Dermal phthalate levels can be used as a matrix for exposure direct absorption from air, particle deposition, and contact with contaminated products. However, the association between dermal phthalate levels in skin wipes and lung function tests remains unknown. A total of 397 participants were included. Spirometry measurements of forced expiratory volume in 1 s (FEV1, L) and forced vital capacity (FVC, L) were calculated. Dermal phthalate levels of diethyl phthalate (DMP), diethyl phthalate (DEP), di(n-butyl) phthalate (DnBP), butyl benzyl phthalate (BBzP), di(2-ethylhexyl) phthalate (DEHP), diisononyl phthalate (DiNP), and diisodecyl phthalate (DiDP) on forehead skin wipes were detected. The one-unit increases in logarithm (log) dermal DnBP (ß = - 0.08; 95% CI - 0.16, - 0.003, p = 0.041), BBzP (ß = - 0.09; 95% CI - 0.16, - 0.02, p = 0.009), DEHP (ß = - 0.07; 95% CI - 0.14, - 0.003, p = 0.042), and DiNP (ß = - 0.08; 95% CI - 0.15, - 0.02, p = 0.017) were significantly associated with decreases in FVC. For elderly participants, one-unit increases in log dermal DnBP (ß = - 0.25; 95% CI - 0.46, - 0.04, p = 0.021), BBzP (ß = - 0.17; 95% CI - 0.33, - 0.01, p = 0.042), and DiDP (ß = - 0.19; 95% CI - 0.39, < 0.01, p = 0.052) were associated with decreases in FEV1. In conclusion, dermal phthalate levels were significantly associated with decreases in lung function tests.

Associations of dermal diethyl phthalate level with changes in lung function test value mediated by absolute eosinophil count: A panel study of adults in southern Taiwan.

Phthalate concentrations in indoor and outdoor dust are associated with respiratory disease. Both immunoglobulin E (IgE) and eosinophil count are associated with airway inflammation from exposure to environmental allergens. Dermal phthalate level can be used as a matrix for assessing personal exposure through direct absorption from the air, particle deposition, or contact with contaminated products. However, the association between dermal phthalate level and changes in lung function test values, as mediated by immunological response, remains unclear. In total, 237 adults in southern Taiwan were recruited. Spirometry measurements (in L) of forced expiratory volume in 1 s (FEV1) and forced vital capacity (FVC) were taken on visits 1 (2016-2018) and 2 (2019). Dermal phthalate level, absolute eosinophil count, and IgE level were recorded on visit 1. Mean changes in FVC and FEV1 decrease pear year, as determined through pairwise comparisons, were significant (diffFVCper year: -0.46, 95% CI: -0.51, -0.41; p < 0.001; diffFEV1per year: -0.37, 95% confidence interval [CI]: -0.41, -0.34; p < 0.001). For FEV1 decrease, log-unit increases in dermal diethyl phthalate (DEP) were positively associated with diffFEV1per year (ß = 0.096; 95% CI: 0.042, 0.150; p = 0.001) and negatively associated with absolute eosinophil count (ß= -0.201; 95% CI: -0.380, -0.023; p= 0.027). Log-unit increases in absolute eosinophil count were negatively associated with diffFEV1per year (ß= -0.109; 95% CI: -0.150, -0.068; p < 0.001). Absolute eosinophil count mediated 19.70% of the association between dermal DEP level and diffFEV1per year. For FVC decrease, log-unit increases in dermal DEP were positively associated with diffFVCper year (ß = 0.095; 95% CI: 0.035, 0.155; p = 0.002) and negatively associated with absolute eosinophil count (ß = -0.243; 95% CI: -0.427, -0.060; p = 0.010). Log-unit increases in absolute eosinophil count were negatively associated with diffFVCper year (ß= -0.122; 95% CI: -0.168, -0.076; p < 0.001). Absolute eosinophil count mediated 29.98% of the association between dermal DEP level and diffFVCper year. The results suggest that dermal DEP level is positively associated with changes in lung function test values and is mediated by absolute eosinophil count.

In vivo positron emission tomography imaging of protease activity by generation of a hydrophobic product from a noninhibitory protease substrate.

PURPOSE: To develop an imaging technology for protease activities in patients that could help in prognosis prediction and in design of personalized, protease-based inhibitors and prodrugs for targeted therapy. EXPERIMENTAL DESIGN: Polyethylene glycol (PEG) was covalently attached to the N-terminus of a hydrophilic peptide substrate (GPLGVR) for matrix metalloproteinase (MMP) to increase hydrophilicity. PEG-peptide was then linked to a hydrophobic tetramethylrhodamine (TMR) domain and labeled with (18)F to form a PEG-peptide-(18)F-TMR probe. Specific cleavage of the probe by MMP2 was tested in vitro by matrix-assisted laser desorption/ionization-time-of-flight (MALDI-TOF). In vivo imaging of MMP2-expressing tumors was evaluated by micro-PET. RESULTS: The hydrophobic TMR fragment (948 Da) was specifically generated by MMP2 enzymes and MMP-expressing HT1080 cells but not control MCF-7 cells. MMP-expressing HT1080 cells and tumors selectively accumulated the hydrolyzed, hydrophobic TMR fragment at sites of protease activity. Importantly, we found that (18)F-labeled probe ((18)F-TMR) preferentially localized in HT1080 tumors but not control MCF-7 tumors as shown by micro-PET. Uptake of the probe in HT1080 tumors was 18.4 ± 1.9-fold greater than in the MCF-7 tumors 30 minutes after injection. These results suggest that the PEG-peptide-(18)F-TMR probe displays high selectivity for imaging MMP activity. CONCLUSIONS: This strategy successfully images MMP expression in vivo and may be extended to other proteases to predict patient prognosis and to design personalized, protease-based inhibitors and prodrug-targeted therapies.

Fluorescence and interactions with thiol compounds of Nile Red-adsorbed gold nanoparticles.

We have investigated the interactions between a variety of thiols and Nile Red-adsorbed gold nanoparticles (NRAuNPs). After adding thiols to solutions of NRAuNPs, the solutions fluoresce strongly as a result of the displacement of a Nile Red-derived product from the surface of the AuNPs. We propose a mechanism for the formation of this NR product on the surface of AuNPs by conducting mass spectrometry, fluorescence, and capillary electrophoresis measurements. By recording the fluorescence changes of the NRAuNP solutions after addition of the thiols, we investigated the interactions between the thiols and NRAuNPs. Using the Langmuir isotherm model, we found that the displacement rate constants for thiols having one carboxyl residue, such as 3-mercaptopropionic acid, fall within the range 0.55-1.19 x 10(-2) s(-1). Thiols containing hydroxyl groups [e.g., 2-mercaptoethanol (2-ME)] or amino groups [e.g., N-(2-mercaptopropionyl)glycine (MPG)], or that have flat structures on the AuNP surface, such as mercaptosuccinic acid, exhibit double-exponential kinetics with first rate constants of 0.51-2.83 x 10(-2) s(-1) and second rate constants of 6.0-23.4 x 10(-4) s(-1). Our results reveal that steric effects and the charge density of the thiols both play important roles in determining the interactions with NRAuNPs. The interactions (displacement and/or induced aggregation) are also dependent on the size of NRAuNPs.

Beyond quantitative proteomics: signal enhancement of the a1 ion as a mass tag for peptide sequencing using dimethyl labeling.

Stable isotope-based dimethyl labeling that produces a dimethyl labeled terminal amine or a monomethylated proline N-terminus by reductive methylation (Anal. Chem. 2003, 75, 6843-6852) was reported as a promising strategy for global quantitative proteomics because of the simplicity of the process and its fast and complete reaction. This labeling strategy provides a signal enhancement for the produced a1 ions, which are usually hard to detect among most of the nonderivatized fragments. To assist peptide sequencing, in this study, the enhanced a1 ion produced under either collision induced dissociation (CID) or post source decay (PSD) modes was further characterized and applied as a mass tag for fingerprinting the identity of N-terminal amino acid. On the basis of the analysis of standard peptides, tryptic digests of hemoglobin and cell lysates, it was proved that such signal enhancement occurred to a1 ions derived from all 20 of the amino acids residues and this phenomenon was explained based the formation of stable quaternary immoniun ions. Accurate determination of a1 ions was shown to increase the chance for peptide de novo sequencing and also provided higher confidence in the scores obtained when identifying a protein through database searching. In addition, the a1 ion was further demonstrated to be used as a universal tag for precursor ion scan in a Q-TOF instrument, leading to a greater number of peptide ions sequenced. Combined with the capability for differential quantitation, the stable isotope-based dimethyl labeling increases the usefulness of the labeling method for MS-based proteomics.