scholarly journals Stability Evaluation of DMT and Harmala Alkaloids in Ayahuasca Tea Samples

Molecules ◽  
2020 ◽  
Vol 25 (9) ◽  
pp. 2072 ◽  
Author(s):  
Gabriela de Oliveira Silveira ◽  
Rafael Guimarães dos Santos ◽  
Felipe Rebello Lourenço ◽  
Giordano Novak Rossi ◽  
Jaime Hallak ◽  
...  
Keyword(s):  
Therapeutic Potential ◽  
Stability Evaluation ◽  
Glass Containers ◽  
Chromatography Tandem Mass Spectrometry ◽  
Liquid Chromatography Tandem Mass ◽  
Harmala Alkaloids ◽  
Health Disorders ◽  
The Stability ◽  
Over Time

Ayahuasca tea is a hallucinogenic beverage used for religious purposes in Brazil and many other countries that has therapeutic potential in the treatment of some mental health disorders. In the context of psychedelic research, quantification of the tea’s main alkaloids prior to its administration in animal or human studies is essential. For this reason, this study aims to provide information regarding the stability of the main ayahuasca alkaloids (dimethyltryptamine, DMT; harmine, HRM; tetrahydroharmine, THH; harmaline, HRL) in three different conditions: (1) A year stored in a refrigerator either in plastic or glass containers, (2) seven days at 37 °C to reproduce usual mail transportation, and (3) after three freeze–thaw cycles. Samples were quantified after a dilute-and-shoot procedure using liquid chromatography tandem mass spectrometry (LC-ESI-MS/MS). There was no significant degradation of DMT concentration over time in all tested conditions. Harmala alkaloids (THH, HRL, and HRM) showed important variations after long-term and high-temperature storages. Although DMT has proven to be stable in all studied conditions, the harmala alkaloids revealed intense degradation and even concentration increment. This may be caused by degradation, alkaloid inter-conversion, and leaching from tea precipitate material. Therefore, ayahuasca quantification before administration in controlled sets is mandatory.

scholarly journals Effect of Photoinitiator on Precursory Stability and Curing Depth of Thiol-Ene Clickable Gelatin

Polymers ◽  
2021 ◽  
Vol 13 (11) ◽  
pp. 1877
Author(s):  
Kai-Hung Yang ◽  
Gabriella Lindberg ◽  
Bram Soliman ◽  
Khoon Lim ◽  
Tim Woodfield ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Visible Light ◽  
Rheological Properties ◽  
Swelling Ratio ◽  
Sodium Persulfate ◽  
Photo Polymerization ◽  
Gelation Kinetics ◽  
The Stability ◽  
Over Time

Recent advances highlight the potential of photopolymerizable allylated gelatin (GelAGE) as a versatile hydrogel with highly tailorable properties. It is, however, unknown how different photoinitiating system affects the stability, gelation kinetics and curing depth of GelAGE. In this study, sol fraction, mass swelling ratio, mechanical properties, rheological properties, and curing depth were evaluated as a function of time with three photo-initiating systems: Irgacure 2959 (Ig2959; 320–500 nm), lithium phenyl-2,4,6-trimethylbenzoylphosphinate (LAP; 320–500 nm), and ruthenium/sodium persulfate (Ru/SPS; 400–500 nm). Results demonstrated that GelAGE precursory solutions mixed with either Ig2959 or LAP remained stable over time while the Ru/SPS system enabled the onset of controllable redox polymerization without irradiation during pre-incubation. Photo-polymerization using the Ru/SPS system was significantly faster (<5 s) compared to both Ig2959 (70 s) and LAP (50 s). Plus, The Ru/SPS system was capable of polymerizing a thick construct (8.88 ± 0.94 mm), while Ig2959 (1.62 ± 0.49 mm) initiated hydrogels displayed poor penetration depth with LAP (7.38 ± 2.13 mm) in between. These results thus support the use of the visible light based Ru/SPS photo-initiator for constructs requiring rapid gelation and a good curing depth while Ig2959 or LAP can be applied for photo-polymerization of GelAGE materials requiring long-term incubation prior to application if UV is not a concern.

Activity networks and the temporality of urban space: the case of a cul-de-sac square

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Ahlam Ammar Sharif
Keyword(s):  
Urban Space ◽  
Actor Network Theory ◽  
Ethnographic Study ◽  
Urban Change ◽  
Content Type ◽  
Activity Networks ◽  
Nuanced Understanding ◽  
The Stability ◽  
Over Time

PurposeThis study draws on recent actor-network theory (ANT) literature to provide a nuanced understanding of the effect of time on activity networks in urban spaces. It investigates the role of time in multiplying these networks and producing urban change, which is limited in similar ANT-related research.Design/methodology/approachThis ethnographic study of a cul-de-sac square within a housing project in the suburb of Dahiyat Al-Hussein in Amman, Jordan, documents the changes in its activity networks when comparing the 1990s with 2019. Data were collected through interviews and site observations covering the two time periods to investigate the different activities that occurred constantly over time, which reflect the temporal network stabilisation within the square.FindingsThe findings demonstrate the profound effect time has on the stability of activity networks related to playing, observing, walking, vending and their interrelations. Their overlaps and conflicts with each other and with other networks in the space were observed. Unpacking the stability of activity networks and their interrelations demonstrates the change in their actor relations and temporalities over time. This is significant in understanding urban change.Originality/valueThe study investigates the importance of time in recognising and extending the multiplicity of urban activities, which suggests new ways of understanding urban change. This exploration highlights new possibilities for creating more adaptable spaces according to residents' long-term needs.

scholarly journals Stability of chemical UV filters in sunscreens exposed to vehicle cabin temperatures

2021 ◽  
pp. 46
Keyword(s):  
Heat Exposure ◽  
Real Life ◽  
Storage Conditions ◽  
Active Ingredients ◽  
Excessive Heat ◽  
Vehicle Cabin ◽  
Chromatography Tandem Mass Spectrometry ◽  
Liquid Chromatography Tandem Mass ◽  
The Stability ◽  
Sunscreen Products

Background: Sunscreen companies recommend replacing your chemical sunscreen every year. Consumer inquiries about product integrity under excessive exposure to heat prompted the FDA to add a requirement statement to sunscreen products indicating a need to protect stored sunscreen from excessive heat and direct sun. If heat exposure indeed affects chemical sunscreen stability, then in some areas, replacement may be warranted earlier than a year. Methods: We examined real-life scenarios related to the storage of sunscreen containers inside vehicles sitting in natural sunlight to provide information about the stability of sunscreen active ingredients under real-life storage conditions. The active ingredients avobenzone, oxybenzone, homosalate, octinoxate, octisalate, and octocrylene in samples of sunscreens were examined after heat exposure over six months using liquid chromatography-tandem mass spectrometry (LC-MS/MS) analysis. The calculated levels of each active ingredient were then compared between the non-heat exposed samples and the heat exposed samples using a paired t-test to look for decreases in active chemicals from heat exposure. Results: No important differences were seen for heat exposure in this study of 378 hours of temperatures above 37.8 °C, with an additional 292 hours of exposure to temperatures of 32.2-37.7 °C, and 3454 hours at 26.7-32.2 °C. Conclusions: This suggests such heat exposure does not result in degradation of the active ingredients of sunscreens with sun protection factors (SPF) of 30 and 50. This is important for individuals attempting to prevent sunburns and skin cancer.

scholarly journals Temporal stability of primate scent samples

2021 ◽  
Vol 3 (4) ◽  
Author(s):  
Alice C. Poirier ◽  
John S. Waterhouse ◽  
Jacob C. Dunn ◽  
Andrew C. Smith
Keyword(s):  
Chemical Composition ◽  
Room Temperature ◽  
Solid Phase ◽  
Temporal Stability ◽  
Gas Chromatography Mass Spectrometry ◽  
Headspace Gas ◽  
The Stability ◽  
Natural Decay ◽  
Over Time

AbstractA common recommendation in the field of animal chemosignaling is to store and transport scent samples frozen, since they are likely to change with time and degrade due to bacterial activity inside the sample containers and the loss of the most volatile compounds. However, we still ignore the exact pattern of change or degradation for these types of samples. Here we experimentally tested the stability of primate scent samples during analytical procedures. For this purpose, we used swabs of naturally deposited glandular secretions from captive tamarins (Neotropical primates) analyzed by headspace gas chromatography-mass spectrometry. We successively extracted the samples by solid-phase microextraction, while controlling for the delay between extractions, and compared the number of compounds detected in the samples under each condition. We found that compounds were lost and transformed over time inside the sample vials. Such natural decay of scent signals is likely to contribute to the long term information transmitted. We found no evidence that long delays at room temperature affected sample chemical composition more than short delays. Nonetheless, we showed that repeated extraction of a sample increased the loss of compounds. The changes in sample chemical composition observed over time in this experiment support standard recommendation to avoid storing samples for long periods at room temperature and to extract each sample only once, in order to ensure optimum results.

scholarly journals Paracrine IFN Response Limits ZIKV Infection in Human Sertoli Cells

2021 ◽  
Vol 12 ◽  
Author(s):  
Daniel P. Strange ◽  
Boonyanudh Jiyarom ◽  
Hooman Sadri-Ardekani ◽  
Lisa H. Cazares ◽  
Tara A. Kenny ◽  
...  
Keyword(s):  
Sertoli Cells ◽  
Cell Types ◽  
Tandem Mass ◽  
Nurse Cells ◽  
Zikv Infection ◽  
Sexually Transmitted ◽  
Chromatography Tandem Mass Spectrometry ◽  
Liquid Chromatography Tandem Mass ◽  
Proteome Changes

Zika virus (ZIKV) is unique among mosquito-borne flaviviruses in its ability to be sexually transmitted. The testes have been implicated as sites of long-term ZIKV replication, and our previous studies have identified Sertoli cells (SC), the nurse cells of the seminiferous epithelium that govern spermatogenesis, as major targets of ZIKV infection. To improve our understanding of the interaction of ZIKV with human SC, we analyzed ZIKV-induced proteome changes in these cells using high-throughput liquid chromatography-tandem mass spectrometry (LC-MS/MS). Our data demonstrated that interferon (IFN) signaling was the most significantly enriched pathway and the antiviral proteins MX1 and IFIT1 were among the top upregulated proteins in SC following ZIKV infection. The dynamic between IFN response and ZIKV infection kinetics in SC remains unclear, therefore we further determined whether MX1 and IFIT1 serve as antiviral effectors against ZIKV. We found that increased levels of MX1 at the later time points of infection coincided with diminished ZIKV infection while the silencing of MX1 and IFIT1 enhanced peak ZIKV propagation in SC. Furthermore, although IFN-I exposure was found to significantly hinder ZIKV replication in SC, IFN response was attenuated in these cells as compared to other cell types. The data in this study highlight IFN-I as a driver of the antiviral state that limits ZIKV infection in SC and suggests that MX1 and IFIT1 function as antiviral effectors against ZIKV in SC. Collectively, this study provides important biological insights into the response of SC to ZIKV infection and the ability of the virus to persist in the testes.

Games for Children with Long-Term Health Problems

2010 ◽  
pp. 286-301 ◽  
Author(s):  
Carolyn Watters ◽  
Sageev Oore ◽  
Hadi Kharrazi
Keyword(s):  
Four Dimensions ◽  
Motivational Constructs ◽  
Health Related ◽  
Interactive Health ◽  
Health Disorders ◽  
High Level ◽  
Level Of Motivation ◽  
The Impact ◽  
Over Time

Games are designed to generate a high level of motivation and engagement in their players. Game players often display intensity in their interaction with and devotion (compulsion) to a game and play the game over and over. In this chapter, the authors present a framework of motivational constructs found in games that are applicable to the design of interactive health software. The framework includes four dimensions of constructs: control, competency, context, and engagement. The authors developed a platform supporting a variety of games that include these constructs, and through two focus groups we examined the impact of these interactions with children with long-term health disorders. The goal is to determine if games developed with health-related goals provide an opportunity to engage children over time with some responsibility for their own condition; that is, can we build games that function like personalized coaches?

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