scholarly journals A mixture of innate cryoprotectants is key for cryopreservation of a drosophilid fly larva.

2021 ◽  
Author(s):  
Lukas Kucera ◽  
Martin Moos ◽  
Tomas Stetina ◽  
Jaroslava Korbelova ◽  
Petr Vodrazka ◽  
...  

Background: Organisms evolved biochemical strategies to cope with environmental stressors. For instance, insects that naturally tolerate internal freezing produce complex mixtures of multiple cryoprotectants (CPs). Better knowledge on composition of these mixtures, and on mechanisms of how the individual CPs interact, could inspire development of laboratory CP formulations optimized for cryopreservation of cells and other biological material. Results: Here we identify and quantify (using high resolution mass spectrometry) a range of putative CPs in larval tissues of a subarctic fly, Chymomyza costata, that survives long-term cryopreservation in liquid nitrogen. The CPs (proline, trehalose, glutamine, asparagine, glycine betaine, glycerophosphoethanolamine, glycerophosphocholine, and sarcosine) accumulate in hemolymph in a ratio of 313:108:55:26:6:4:3:0.5 mmol.L-1. Using calorimetry, we show that the artificial mixtures, mimicking the concentrations of major CPs' in hemolymph of freeze-tolerant larvae, suppress the melting point of water and significantly reduce the ice fraction. We demonstrate in a bioassay that mixtures of CPs administered through the diet act synergistically rather than additively to enable cryopreservation of otherwise freeze-sensitive larvae. Using MALDI-MSI, we show that during slow extracellular freezing of whole larvae trehalose becomes concentrated in partially dehydrated hemolymph and stimulates transition to the amorphous glass phase. In contrast, proline moves to the boundary between extracellular ice and dehydrated hemolymph and tissues where it likely forms a layer of dense viscoelastic liquid. Conclusion: Our results suggest that different components of innate cryoprotective mixtures of freeze-tolerant insect act in synergy during extracellular freezing. We propose that transitions to amorphous glass (stimulated by trehalose) and viscoelastic liquids (having proline as major component) may protect macromolecules and cells from thermomechanical shocks associated with freezing and transfer into and out of liquid nitrogen.

2008 ◽  
Vol 59 (7) ◽  
Author(s):  
Ileana Vajiala ◽  
Ruxandra Subasu ◽  
Mirela Zorio ◽  
Rodica Picu

Upon screening identification of Stanozolol, GC/HRMS confirmation of the suspicious sample is done by reanalysis of the urine specimen, where a specific immunoaffinity purification procedure is used to selectively isolate the long term excreted metabolites of Stanozolol. By meeting the specific identification criteria for more than one metabolite of the same parent compound, additional evidence could be obtained in the decision making process in doping control.


Author(s):  
David M. Willumsen

The central argument of this book is that voting unity in European legislatures is not primarily the result of the ‘disciplining’ power of the leadership of parliamentary parties, but rather the result of a combination of ideological homogeneity through self-selection into political parties and the calculations of individual legislators about their own long-term benefits. Despite the central role of policy preferences in the subsequent behaviour of legislators, preferences at the level of the individual legislator have been almost entirely neglected in the study of parliaments and legislative behaviour. The book measures these using an until now under-utilized resource: parliamentary surveys. Building on these, the book develops measures of policy incentives of legislators to dissent from their parliamentary parties, and show that preference similarity amongst legislators explains a very substantial proportion of party unity, yet alone cannot explain all of it. Analysing the attitudes of legislators to the demands of party unity, and what drives these attitudes, the book argues that what explains the observed unity (beyond what preference similarity would explain) is the conscious acceptance by MPs that the long-term benefits of belonging to a united party (such as increased influence on legislation, lower transaction costs, and better chances of gaining office) outweigh the short-terms benefits of always voting for their ideal policy outcome. The book buttresses this argument through the analysis of both open-ended survey questions as well as survey questions on the costs and benefits of belonging to a political party in a legislature.


2020 ◽  
Vol 4 (Supplement_1) ◽  
pp. 714-715
Author(s):  
Marie Gualtieri

Abstract The recent reauthorization of the Older Americans Act adds language and definitions to current issues facing the aging population. Specifically, Title I includes definitions related to program adaptation and coordination, workforce and long-term care issues, nutrition and social isolation, as well as family caregivers. Different from the last authorization, these definitions span beyond the individual experience to include other entities impacted by an aging society, such as the workforce and families. Overall, the Title I reauthorization seeks to modernize policy to reflect the current influx of the older adult population and its consequences.


2020 ◽  
pp. 030802262097951
Author(s):  
Lizette Norin ◽  
Björn Slaug ◽  
Maria Haak ◽  
Susanne Iwarsson

Introduction Adults with spinal cord injuries are living longer than previously, and a majority are living in ordinary housing in the community. Housing accessibility is important for maintaining independent occupational performance for this population, but knowledge in this area is insufficient. We investigated housing adaptations and current accessibility problems among older adults with long-standing (>10 years) spinal cord injuries. Method Data from home visits among 122 older adults with spinal cord injuries in Sweden were used. Housing adaptations and environmental barriers were descriptively analysed. Findings Kitchens, entrances, and hygiene areas were common locations for housing adaptations and environmental barriers that generated accessibility problems. The most common adaptations were ramps, wheelchair-accessible stovetops, and ceiling-lifts. Wall-mounted cupboards and high shelves (kitchen), inaccessible storage areas (outside the dwelling), and a lack of grab bars (hygiene area) generated the most accessibility problems. Conclusion Despite housing adaptations, there are considerable accessibility problems in the dwellings of older adults with long-standing spinal cord injuries in Sweden, indicating that long-term follow-up of the housing situation of this population is necessary. Focusing on accessible housing as a prerequisite for occupational performance is at the core of occupational therapy, deserving attention on the individual as well as the societal level.


2021 ◽  
Vol 22 (12) ◽  
pp. 6313
Author(s):  
Marcelo T. Moura ◽  
Laís B. Latorraca ◽  
Fabíola F. Paula-Lopes

Mammals face environmental stressors throughout their lifespan, which may jeopardize cellular homeostasis. Hence, these organisms have acquired mechanisms to cope with stressors by sensing, repairing the damage, and reallocating resources to increase the odds of long-term survival. Autophagy is a pro-survival lysosome-mediated cytoplasm degradation pathway for organelle and macromolecule recycling. Furthermore, autophagy efflux increases, and this pathway becomes idiosyncratic depending upon developmental and environmental contexts. Mammalian germ cells and preimplantation embryos are attractive models for dissecting autophagy due to their metastable phenotypes during differentiation and exposure to varying environmental cues. The aim of this review is to explore autophagy during mammalian gametogenesis, fertilization and preimplantation embryonic development by contemplating its physiological role during development, under key stressors, and within the scope of assisted reproduction technologies.


2021 ◽  
Vol 22 (12) ◽  
pp. 6274
Author(s):  
María Fernández ◽  
Alicia de de Coo ◽  
Inés Quintela ◽  
Eliane García ◽  
Márcio Diniz-Freitas ◽  
...  

Severe periodontitis is prevalent in Down syndrome (DS). This study aimed to identify genetic variations associated with periodontitis in individuals with DS. The study group was distributed into DS patients with periodontitis (n = 50) and DS patients with healthy periodontium (n = 36). All samples were genotyped with the “Axiom Spanish Biobank” array, which contains 757,836 markers. An association analysis at the individual marker level using logistic regression, as well as at the gene level applying the sequence kernel association test (SKAT) was performed. The most significant genes were included in a pathway analysis using the free DAVID software. C12orf74 (rs4315121, p = 9.85 × 10−05, OR = 8.84), LOC101930064 (rs4814890, p = 9.61 × 10−05, OR = 0.13), KBTBD12 (rs1549874, p = 8.27 × 10−05, OR = 0.08), PIWIL1 (rs11060842, p = 7.82 × 10−05, OR = 9.05) and C16orf82 (rs62030877, p = 8.92 × 10−05, OR = 0.14) showed a higher probability in the individual analysis. The analysis at the gene level highlighted PIWIL, MIR9-2, LHCGR, TPR and BCR. At the signaling pathway level, PI3K-Akt, long-term depression and FoxO achieved nominal significance (p = 1.3 × 10−02, p = 5.1 × 10−03, p = 1.2 × 10−02, respectively). In summary, various metabolic pathways are involved in the pathogenesis of periodontitis in DS, including PI3K-Akt, which regulates cell proliferation and inflammatory response.


Economies ◽  
2021 ◽  
Vol 9 (1) ◽  
pp. 18 ◽  
Author(s):  
Daniel Němec ◽  
Eva Kotlánová ◽  
Igor Kotlán ◽  
Zuzana Machová

While assessing the economic impacts of corruption, the corruption-related transmission channels which influence taxation as such have to be duly considered. Taking the example of the Czech Republic, this article aims to evaluate the impacts corruption has on the size of the shadow economy as well as on the individual sources of long-term economic growth, making use of a transmission channel through which corruption affects the tax burden components. Using the method of an extended DSGE model, it confirms the initial assumption that an increase in perceived corruption supports the shadow economy’s growth, but at the same time, it demonstrates that corruption and especially its perception has a significantly different effect on two key areas—the capital accumulation and the labour force size. It further identifies another sector of the economy representing taxes which are prone to tax evasion while asserting that corruption has a much more destructive effect on this sector of the economy, offering generalized implications for other post-communist EU member states in a similar situation.


2020 ◽  
Vol 2 (2) ◽  
Author(s):  
Sara Baldini ◽  
Francesca Pittau ◽  
Gwenael Birot ◽  
Vincent Rochas ◽  
Miralena I Tomescu ◽  
...  

Abstract Monitoring epileptic activity in the absence of interictal discharges is a major need given the well-established lack of reliability of patients’ reports of their seizures. Up to now, there are no other tools than reviewing the seizure diary; however, seizures may not be remembered or dismissed voluntarily. In the present study, we set out to determine if EEG voltage maps of epileptogenic activity in individual patients can help to identify disease activity, even if their scalp EEG appears normal. Twenty-five patients with pharmacoresistant focal epilepsy were included. For each patient, 6 min of EEG with spikes (yes-spike) and without visually detectable epileptogenic discharges (no-spike) were selected from long-term monitoring recordings (EEG 31–37 channels). For each patient, we identified typical discharges, calculated their average and the corresponding scalp voltage map (‘spike-map’). We then fitted the spike-map for each patient on their (i) EEG epochs with visible spikes, (ii) epochs without any visible spike and (iii) EEGs of 48 controls. The global explained variance was used to estimate the presence of the spike-maps. The individual spike-map occurred more often in the spike-free EEGs of patients compared to EEGs of healthy controls (P = 0.001). Not surprisingly, this difference was higher if the EEGs contained spikes (P < 0.001). In patients, spike-maps were more frequent per second (P < 0.001) but with a shorter mean duration (P < 0.001) than in controls, for both no-spike and yes-spike EEGs. The amount of spike-maps was unrelated to clinical variables, like epilepsy severity, drug load or vigilance state. Voltage maps of spike activity are present very frequently in the scalp EEG of patients, even in presumably normal EEG. We conclude that spike-maps are a robust and potentially powerful marker to monitor subtle epileptogenic activity.


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