Although dinoflagellates are a potential source of pharmaceuticals and natural products, the mechanisms for regulating and producing these compounds are largely unknown because of extensive ...post-transcriptional control of gene expression. One well-documented mechanism for controlling gene expression during translation is codon bias, whereby specific codons slow or even terminate protein synthesis. Approximately 10,000 annotatable genes from fifteen "core" dinoflagellate transcriptomes along a range of overall guanine and cytosine (GC) content were used for codonW analysis to determine the relative synonymous codon usage (RSCU) and the GC content at each codon position. GC bias in the analyzed dataset and at the third codon position varied from 51% and 54% to 66% and 88%, respectively. Codons poor in GC were observed to be universally absent, but bias was most pronounced for codons ending in uracil followed by adenine (UA). GC bias at the third codon position was able to explain low abundance codons as well as the low effective number of codons. Thus, we propose that a bias towards codons rich in GC bases is a universal feature of core dinoflagellates, possibly relating to their unique chromosome structure, and not likely a major mechanism for controlling gene expression.
Chemometric analysis of comprehensive two-dimensional chromatography coupled to time-of-flight mass spectrometry (GC×GC-TOFMS) data has been reported with various workflows, yet little effort has ...been devoted to evaluating the impacts of workflow variation on study conclusions. The report presented herein aims to investigate the effects of different pre-processing and variable selection strategies on the scores’ plot outputs from GC×GC-TOFMS data acquired from lavender and tea tree essential oils. Our results suggest that pre-processing, such as applying log transformation to the data set, can result in significant differentiation of sample clustering when compared to only mean centering. Additionally, exploring differences between analysis of variance, Fisher-ratio, and partial least squares-discriminant analysis feature selection resulted in little variation in scores plots. This work highlights the effects different chemometric workflows can have on results to help facilitate harmonization efforts.
The chemical properties of poly- and perfluoroalkyl substances (PFASs) make them widespread for use in a number of industrial and commercial products to confer water and oil-repellency ...characteristics and to reduce surface tension e.g. in aqueous film-forming foams (AFFFs). Some PFASs, especially perfluoroctane sulfonate, and several perfluoroalkyl carboxylic acids, are known to cause significant human and environmental negative impact. Our knowledge on the content of PFASs in products remains scarce due to limited information available, thus impeding any precise assessment of human exposure and environmental release upon use. This study aimed at analyzing a wide variety of liquid products (n = 194) likely to contain PFASs, including impregnating agents, lubricants, cleansers, polishes, AFFFs and other industrial products. By means of LC- and GC-MS/MS analytical techniques, 24 PFASs (from 41 targeted PFASs) were detected and quantified in 55% of samples. PFAS quantification and profiling was found to be consumer product specific. PFASs were mostly detected in AFFF (90%) and impregnating agents (60%) with mainly ionic and neutral species, respectively. In particular, the fluorotelomer alcohols 6:2, 8:2 and 10:2 FTOHs were detected in 40–50% of impregnating agents. Further investigation by Fast Atom Bombardment Mass Spectrometry (FAB-MS) on a set of AFFF samples allowed the characterization of 8 different PFAS classes as major components in these formulations. Results demonstrated that numerous and diversified PFAS are currently used in specific commercial products, implying significant human exposure and environmental release that necessitate further research concerning their toxicological impact.
Display omitted
•Polyfluoroalkyl substances (PFASs) are causing concern for human and environment.•194 consumer products were screened for 41 individual PFASs.•24 PFASs were quantified in the 0.1–25000 ppm range.•Additional 8 new structural classes of PFAS were detected in AFFFs.•Results indicate potentially significant human exposure to fluorotelomer alcohols.
Non-targeted analysis (NTA) and suspect screening analysis (SSA) are powerful techniques that rely on high-resolution mass spectrometry (HRMS) and computational tools to detect and identify unknown ...or suspected chemicals in the exposome. Fully understanding the chemical exposome requires characterization of both environmental media and human specimens. As such, we conducted a review to examine the use of different NTA and SSA methods in various exposure media and human samples, including the results and chemicals detected. The literature review was conducted by searching literature databases, such as PubMed and Web of Science, for keywords, such as "non-targeted analysis", "suspect screening analysis" and the exposure media. Sources of human exposure to environmental chemicals discussed in this review include water, air, soil/sediment, dust, and food and consumer products. The use of NTA for exposure discovery in human biospecimen is also reviewed. The chemical space that has been captured using NTA varies by media analyzed and analytical platform. In each media the chemicals that were frequently detected using NTA were: per- and polyfluoroalkyl substances (PFAS) and pharmaceuticals in water, pesticides and polyaromatic hydrocarbons (PAHs) in soil and sediment, volatile and semi-volatile organic compounds in air, flame retardants in dust, plasticizers in consumer products, and plasticizers, pesticides, and halogenated compounds in human samples. Some studies reviewed herein used both liquid chromatography (LC) and gas chromatography (GC) HRMS to increase the detected chemical space (16%); however, the majority (51%) only used LC-HRMS and fewer used GC-HRMS (32%). Finally, we identify knowledge and technology gaps that must be overcome to fully assess potential chemical exposures using NTA. Understanding the chemical space is essential to identifying and prioritizing gaps in our understanding of exposure sources and prior exposures. IMPACT STATEMENT: This review examines the results and chemicals detected by analyzing exposure media and human samples using high-resolution mass spectrometry based non-targeted analysis (NTA) and suspect screening analysis (SSA).
Display omitted
•Multifunctional microcapsules were prepared and characterized.•The encapsulation of the repellent, picardin was achieved.•Microcapsules are stable in solution for extended durations ...of time.•NyCo fabric retains antimicrobial and antifungal properties after MC adsorption.
Insects and microbes can cause disease and corrode materiel deployed in humid environments. Materials with multifunctional properties are highly desirable to the Army to create textile products that would inherently mitigate these issues and decrease Soldier load. Microcapsules (MCs) that encapsulate active compounds such as insect repellents are a potential platform to accomplish this. MCs that exhibit antibacterial and antifungal properties were prepared using an antimicrobial polymer, PHMB, as the shell, and the encapsulation of an insect repellent, picaridin, is reported. MCs are spherical, uniform, and demonstrate a positive zeta potential. FTIR analysis confirms the presence of both active components. MCs were studied for storage stability and their ability to impart functionality to a military relevant textile. Microscopy images demonstrate that MCs remain stable when stored in diH2O for at least six months. Antibacterial activity is observed for MC concentrations across two orders of magnitude in solution. MCs were adsorbed onto a 50:50 nylon:cotton blend (NyCo) as a model for functionalized materiel. GC data indicates that picaridin loading levels are more than ten times the required dose for deterring mosquitoes and both antibacterial and antifungal properties are exhibited. Treated fabric is resistant to fungal growth throughout a four week culture period. A four week storage study demonstrates no discernible loss in picaridin content, and NyCo swatches sustain at least a three log reduction in bacteria growth for all time points. The findings detailed in the following report suggest that these PHMB-based MCs could be used to functionalize materials against microbial organisms and mosquitoes, and are robust enough to endure storage in their crude form and as a coating.
We measured plasma levels of cortisol and corticosterone in female yellow-pine chipmunks (Tamias amoenus) while observing seasonal reproductive and life-history events by live-trapping a natural ...population during the active (nonhibernating) season. Both glucocorticosteroids (GCs) varied significantly from March through September, starting with minimal values at the time of mating (cortisol ∼900 ng/ml, corticosterone ∼50 ng/ml), rising to a peak by late lactation (cortisol ∼1600 ng/ml, corticosterone ∼175 ng/ml), and then declining prior to hibernation. Following their emergence from natal burrows, young of the year had GC levels indistinguishable from those of adults. Body mass also varied significantly over the season, increasing after mating and again after parturition to a peak in lactation, after which it declined steadily until hibernation. In addition to the use of standard trapping to describe seasonal hormonal patterns, we also trapped chipmunks using a special protocol to examine the effects of capture and handling on GCs; we obtained an initial (basal) blood sample immediately, within 1–3 min of observing a capture, and then a second sample 30 min after holding the animal in the trap. Chipmunks consistently increased GCs above the initial (basal) level during the 30 min after capture and initial handling; these significant increases in GCs ranged approximately 70–130% for cortisol and 50–190% for corticosterone, depending on season and reproductive state. GC levels at 30 min after capture and handling were similar to those obtained from samples drawn from our standard trapping and blood sampling. We conclude that although capture and handling increase the absolute level of plasma GC hormones, that effect does not obscure natural patterns of seasonal variation in GCs. Overall, our observations suggest an important role of adrenocortical activity in the energy balance of these free-living rodents in two different contexts: (1) the seasonal regulation of physiological state, including body mass, energy reserves, and reproductive function, and (2) an acute response to stimulatory events, encompassing physiological stress, as represented here by capture and handling.
The bidirectional exchange of gases between vegetation and the atmosphere is controlled by a variety of environmental factors and feedbacks that are entangled and difficult to quantify. As a result ...of this complexity, parameterizations of canopy conductance (G c) in atmospheric models introduce large uncertainties and likely biases into representations of atmosphere–biosphere gas exchange. We present a novel representation of canopy conductance derived from measurements of solar-induced fluorescence (SIF) from the TROPOspheric Monitoring Instrument (TROPOMI). We show a strong linear correlation between GPP and G c, calculated using the Penman–Monteith theory, across a variety of ecosystem types in the AmeriFlux network. We couple this G c–GPP correlation to previous research showing a strong linear correlation between SIF and GPP and estimate G c at a 500 m spatial resolution across the continental United States. We also combine our model with surface estimates of NO2 and PAN from WRF-Chem to estimate stomatal deposition fluxes of these gases. Our results suggest that satellite measurements of SIF can provide important constraints on model representations of stomatal activity and canopy gas exchange on regional and global scales.
Display omitted
•Fine Australian Chardonnay and Shiraz wine sensory and volatile profiles were defined.•Wines of both varieties showed subtle patterns of sub-regional typicality.•Winemaking ...influences described the sample set better than region.•Chardonnay and Shiraz wine regional typicality cannot be defined solely on geographic origin.
Establishing a fine wine image through regional typicality has been of interest to New World wine producing countries like Australia, but previous research mainly involved unoaked experimental wines, which were not reflective of the retail wine market. The regional typicality of commercially available fine Australian wines (FAW) was therefore explored, based on the hypotheses that sensory and chemical composition of varietal fine wines would discriminate by region, and further nuances within region would be explained by drivers of intraregional typicality. Chardonnay wines (2015 vintage) from Margaret River (MR, n = 16) and Yarra Valley (YV, n = 16); and Shiraz wines (2014 vintage) from Barossa Valley (BV, n = 16) and McLaren Vale (MV = 15), were selected for descriptive sensory analysis and underwent profiling of volatiles by gas chromatography-mass spectrometry (GC–MS). For both grape varieties, there was large variability in wine styles among wines from the same GI, such as fruity/crisp vs oaked Chardonnay and oaky/astringent vs savoury Shiraz. Consequently, human intervention seemed to be an important component of regional/sub-regional typicality, which therefore cannot be determined solely on geographic origin of the fruit. Using a combination of sensory markers and volatile profiles allowed the building of regional typicality models, which are promising, however, consumers may not perceive sub-regional differences based on sensory attributes. Undoubtedly, variation of wine styles emerging across wine regions, vintages, and viticultural and winemaking practices needs to be further explored, but this work created a preliminary sensory and volatile map for future research.
•Various approaches to two-dimensional liquid chromatography peak integration are presented.•The impact of multiple peak-integration parameters on quantitation is evaluated.•Optimal peak-integration ...approaches, as dependent on peak quality, are discussed.
Comprehensive, two-dimensional liquid chromatography (LC×LC) is a powerful technique for the separation of complex mixtures. Most studies using LC×LC are focused on qualitative efforts, such as increasing peak capacity. The present study examined the use of LC×LC–UV/vis for the separation and quantitation of polycyclic aromatic hydrocarbons (PAHs). More specifically, this study evaluated the impact of different peak integration approaches on the quantitative performance of the LC×LC method. For well-resolved three-dimensional peaks, parameters such as baseline definition, peak base shape, and peak width determination did not have a significant impact on accuracy and precision. For less-resolved peaks, a dropped baseline and the summation of all slices in the peak improved the accuracy and precision of the integration methods. The computational approaches to three-dimensional peak integration are provided, including fully descriptive, select slice, and summed heights integration methods, each with its own strengths and weaknesses. Overall, the integration methods presented quantify each of the PAHs within acceptable precision and accuracy ranges and have comparable performance to that of single dimension liquid chromatography.
Epigenetic mechanisms play important roles in the neurobiology of substance use disorder. In particular, bromodomain and extra-terminal domain (BET) proteins, a class of histone acetylation readers, ...have been found to regulate cocaine conditioned behaviors, but their role in the behavioral response to other drugs of abuse remains unclear. To address this knowledge gap, we examined the effects of the BET inhibitor, JQ1, on nicotine, amphetamine, morphine, and oxycodone conditioned place preference (CPP). Similar to previous cocaine studies, systemic administration of JQ1 caused a dose-dependent reduction in the acquisition of amphetamine and nicotine CPP in male mice. However, in opioid studies, JQ1 did not alter morphine or oxycodone CPP. Investigating the effects of JQ1 on other types of learning and memory, we found that JQ1 did not alter the acquisition of contextual fear conditioning. Together, these results indicate that BET proteins play an important role in the acquisition of psychostimulant-induced CPP but not the acquisition of opioid-induced CPP nor contextual fear conditioning.
PDF
