scholarly journals What are extreme environmental conditions and how do organisms cope with them?

2011 ◽  
Vol 57 (3) ◽  
pp. 363-374 ◽  
Author(s):  
John C. Wingfield ◽  
J. Patrick Kelley ◽  
Frédéric Angelier
Keyword(s):  
Environmental Conditions ◽  
Acute Stress ◽  
Extreme Environment ◽  
Target Cells ◽  
Extreme Conditions ◽  
Alpine Regions ◽  
The Individual ◽  
The Brain ◽  
Pituitary Adrenal Axis ◽  
Interaction With Receptors

Abstract Severe environmental conditions affect organisms in two major ways. The environment may be predictably severe such as in deserts, polar and alpine regions, or individuals may be exposed to temporarily extreme conditions through weather, presence of predators, lack of food, social status etc. Existence in an extreme environment may be possible, but then to breed or molt in addition can present major bottlenecks that have resulted in the evolution of hormone-behavior adaptations to cope with unpredictable events. Examples of hormone-behavior adaptations in extreme conditions include attenuated testosterone secretion because territoriality and excess courtship may be too costly when there is one opportunity to reproduce. The individual may even become insensitive to testosterone when target areas of the brain regulating reproductive behavior no longer respond to the hormone. A second example is reduced sensitivity to glucocorticoids following acute stress during the breeding season or molt that allows successful reproduction and/or a vital renewal of the integument to endure extreme conditions during the rest of the year. Reduced sensitivity could involve: (a) modulated response of the hypothalamo-pituitary-adrenal axis, (b) reduced sensitivity to high glucocorticoid levels, or (c) a combination of (a) and (b). Moreover, corticosteroid binding proteins (CBP) buffer responses to stress by reducing the movement of glucocorticoids into target cells. Finally, intracellular enzymes (11β-hydroxysteroid dehydrogenase and variants) can deactivate glucocorticoids entering cells thus reducing interaction with receptors. These mechanisms have important implications for climate change and increasing extremes of weather.

scholarly journals Exploring Marine Environments for the Identification of Extremophiles and Their Enzymes for Sustainable and Green Bioprocesses

2018 ◽  
Vol 11 (1) ◽  
pp. 149 ◽  
Author(s):  
Paola Di Donato ◽  
Andrea Buono ◽  
Annarita Poli ◽  
Ilaria Finore ◽  
Gennaro Abbamondi ◽  
...  
Keyword(s):  
New Species ◽  
Environmental Conditions ◽  
Extreme Environment ◽  
Life Forms ◽  
Industrial Processes ◽  
Extreme Conditions ◽  
Marine Environments ◽  
Biotechnological Applications ◽  
Green Biotechnology ◽  
Living Organisms

Sea environments harbor a wide variety of life forms that have adapted to live in hard and sometimes extreme conditions. Among the marine living organisms, extremophiles represent a group of microorganisms that attract increasing interest in relation to their ability to produce an array of molecules that enable them to thrive in almost every marine environment. Extremophiles can be found in virtually every extreme environment on Earth, since they can tolerate very harsh environmental conditions in terms of temperature, pH, pressure, radiation, etc. Marine extremophiles are the focus of growing interest in relation to their ability to produce biotechnologically useful enzymes, the so-called extremozymes. Thanks to their resistance to temperature, pH, salt, and pollutants, marine extremozymes are promising biocatalysts for new and sustainable industrial processes, thus representing an opportunity for several biotechnological applications. Since the marine microbioma, i.e., the complex of microorganisms living in sea environments, is still largely unexplored finding new species is a central issue for green biotechnology. Here we described the main marine environments where extremophiles can be found, some existing or potential biotechnological applications of marine extremozymes for biofuels production and bioremediation, and some possible approaches for the search of new biotechnologically useful species from marine environments.

scholarly journals Acute Stress Differentially Affects Aromatase Activity in Specific Brain Nuclei of Adult Male and Female Quail

Endocrinology ◽  
2011 ◽  
Vol 152 (11) ◽  
pp. 4242-4251 ◽  
Author(s):  
Molly J. Dickens ◽  
Charlotte A. Cornil ◽  
Jacques Balthazart
Keyword(s):  
Reproductive Behavior ◽  
Acute Stress ◽  
Aromatase Activity ◽  
Brain Nuclei ◽  
Male And Female ◽  
Estrogen Production ◽  
Female Quail ◽  
Male Reproductive Behavior ◽  
The Individual ◽  
The Brain

The rapid and temporary suppression of reproductive behavior is often assumed to be an important feature of the adaptive acute stress response. However, how this suppression operates at the mechanistic level is poorly understood. The enzyme aromatase converts testosterone to estradiol in the brain to activate reproductive behavior in male Japanese quail (Coturnix japonica). The discovery of rapid and reversible modification of aromatase activity (AA) provides a potential mechanism for fast, stress-induced changes in behavior. We investigated the effects of acute stress on AA in both sexes by measuring enzyme activity in all aromatase-expressing brain nuclei before, during, and after 30 min of acute restraint stress. We show here that acute stress rapidly alters AA in the male and female brain and that these changes are specific to the brain nuclei and sex of the individual. Specifically, acute stress rapidly (5 min) increased AA in the male medial preoptic nucleus, a region controlling male reproductive behavior; in females, a similar increase was also observed, but it appeared delayed (15 min) and had smaller amplitude. In the ventromedial and tuberal hypothalamus, regions associated with female reproductive behavior, stress induced a quick and sustained decrease in AA in females, but in males, only a slight increase (ventromedial) or no change (tuberal) in AA was observed. Effects of acute stress on brain estrogen production, therefore, represent one potential way through which stress affects reproduction.

Fit Vs Faint: Assessing Work Causation in “Idiopathic Fall” Cases

2014 ◽  
Vol 19 (5) ◽  
pp. 3-12
Author(s):  
Lorne Direnfeld ◽  
David B. Torrey ◽  
Jim Black ◽  
LuAnn Haley ◽  
Christopher R. Brigham
Keyword(s):  
Blood Flow ◽  
Electrical Activity ◽  
Loss Of Consciousness ◽  
Brain Electrical Activity ◽  
Medical Terminology ◽  
Scientific Analysis ◽  
Medical Causation ◽  
The Individual ◽  
The Brain ◽  
Current Science

Abstract When an individual falls due to a nonwork-related episode of dizziness, hits their head and sustains injury, do workers’ compensation laws consider such injuries to be compensable? Bearing in mind that each state makes its own laws, the answer depends on what caused the loss of consciousness, and the second asks specifically what happened in the fall that caused the injury? The first question speaks to medical causation, which applies scientific analysis to determine the cause of the problem. The second question addresses legal causation: Under what factual circumstances are injuries of this type potentially covered under the law? Much nuance attends this analysis. The authors discuss idiopathic falls, which in this context means “unique to the individual” as opposed to “of unknown cause,” which is the familiar medical terminology. The article presents three detailed case studies that describe falls that had their genesis in episodes of loss of consciousness, followed by analyses by lawyer or judge authors who address the issue of compensability, including three scenarios from Arizona, California, and Pennsylvania. A medical (scientific) analysis must be thorough and must determine the facts regarding the fall and what occurred: Was the fall due to a fit (eg, a seizure with loss of consciousness attributable to anormal brain electrical activity) or a faint (eg, loss of consciousness attributable to a decrease in blood flow to the brain? The evaluator should be able to fully explain the basis for the conclusions, including references to current science.

Neurotoxic and Neuroprotective Role of Exosomes in Parkinson’s Disease

2020 ◽  
Vol 25 (42) ◽  
pp. 4510-4522 ◽  
Author(s):  
Biancamaria Longoni ◽  
Irene Fasciani ◽  
Shivakumar Kolachalam ◽  
Ilaria Pietrantoni ◽  
Francesco Marampon ◽  
...  
Keyword(s):  
Parkinson’S Disease ◽  
Parkinson's Disease ◽  
Potential Role ◽  
Current Knowledge ◽  
Biological Fluids ◽  
Cell Communication ◽  
Target Cells ◽  
Cellular Debris ◽  
The Brain

: Exosomes are extracellular vesicles produced by eukaryotic cells that are also found in most biological fluids and tissues. While they were initially thought to act as compartments for removal of cellular debris, they are now recognized as important tools for cell-to-cell communication and for the transfer of pathogens between the cells. They have attracted particular interest in neurodegenerative diseases for their potential role in transferring prion-like proteins between neurons, and in Parkinson’s disease (PD), they have been shown to spread oligomers of α-synuclein in the brain accelerating the progression of this pathology. A potential neuroprotective role of exosomes has also been equally proposed in PD as they could limit the toxicity of α-synuclein by clearing them out of the cells. Exosomes have also attracted considerable attention for use as drug vehicles. Being nonimmunogenic in nature, they provide an unprecedented opportunity to enhance the delivery of incorporated drugs to target cells. In this review, we discuss current knowledge about the potential neurotoxic and neuroprotective role of exosomes and their potential application as drug delivery systems in PD.

Fact file 1: Critical care and emergency medicine

2017 ◽  
Author(s):  
Daisy Fancourt
Keyword(s):  
Emergency Medicine ◽  
Critical Care ◽  
Sports Medicine ◽  
Orthopaedic Surgery ◽  
Extreme Environment ◽  
Disaster Medicine ◽  
Medical Attention ◽  
Life Threatening ◽  
Medical Disciplines ◽  
The Brain

Emergency medicine involves the care of patients who require immediate medical attention. The specialty encompasses a broad range of medical disciplines, including anaesthesia, cardiology (a field related to the heart), neurology (a field related to the brain), plastic surgery, orthopaedic surgery (surgery relating to the bones or muscles), and cardiothoracic surgery (surgery relating to the heart, chest, or lungs). There are also a number of subspecialties including extreme environment medicine, disaster medicine and sports medicine. Related to emergency medicine is the specialty of critical care medicine, which is concerned with the care of patients with life-threatening conditions often treated in intensive care settings....

Individual Uniqueness in the Neonatal Functional Connectome

2021 ◽  
Author(s):  
Qiushi Wang ◽  
Yuehua Xu ◽  
Tengda Zhao ◽  
Zhilei Xu ◽  
Yong He ◽  
...  
Keyword(s):  
Individual Differences ◽  
Individual Identification ◽  
Imaging Data ◽  
Functional Connectome ◽  
Middle Range ◽  
Human Connectome Project ◽  
The Individual ◽  
And Behavior ◽  
Identification Analysis ◽  
The Brain

Abstract The functional connectome is highly distinctive in adults and adolescents, underlying individual differences in cognition and behavior. However, it remains unknown whether the individual uniqueness of the functional connectome is present in neonates, who are far from mature. Here, we utilized the multiband resting-state functional magnetic resonance imaging data of 40 healthy neonates from the Developing Human Connectome Project and a split-half analysis approach to characterize the uniqueness of the functional connectome in the neonatal brain. Through functional connectome-based individual identification analysis, we found that all the neonates were correctly identified, with the most discriminative regions predominantly confined to the higher-order cortices (e.g., prefrontal and parietal regions). The connectivities with the highest contributions to individual uniqueness were primarily located between different functional systems, and the short- (0–30 mm) and middle-range (30–60 mm) connectivities were more distinctive than the long-range (>60 mm) connectivities. Interestingly, we found that functional data with a scanning length longer than 3.5 min were able to capture the individual uniqueness in the functional connectome. Our results highlight that individual uniqueness is present in the functional connectome of neonates and provide insights into the brain mechanisms underlying individual differences in cognition and behavior later in life.

scholarly journals Inter and intraspecies comparison of the level of selected bacterial phyla in in cattle and sheep based on feces

2021 ◽  
Vol 17 (1) ◽  
Author(s):  
Natalia Szeligowska ◽  
Paulina Cholewińska ◽  
Katarzyna Czyż ◽  
Konrad Wojnarowski ◽  
Marzena Janczak
Keyword(s):  
Digestive Tract ◽  
Environmental Conditions ◽  
Genetic Factors ◽  
Disease Symptoms ◽  
Microbiome Composition ◽  
Bacterial Phyla ◽  
As Species ◽  
Individual Host ◽  
Host Effect ◽  
The Individual

Abstract Background The microbiome of the digestive tract of ruminants contains microbial ecosystem that is affected by both environmental and genetic factors. The subject of this study concerns the influence of selected genetic factors, such as species of animals and “host” individual differences on the digestive tract microbiome composition. The results show the core microbiological composition (Firmicutes and Bacteroidetes) of ruminants digestive tract (based on feces) depending on breed and “host”. The Bacteroidetes and Firmicutes phyla are the most abundant in ruminants digestive tract. The aim of the study was to determine the differences prevalence level of Bacteroidetes and Firmicutes phyla in feces of Charolaise cattle and Polish Olkuska Sheep with respect to intra- and inter-species variability. Results The research group in the experiment consisted of animals at the age of 3 months kept in the same environmental conditions – rams of Polish Olkuska Sheep (n = 10) and Charolaise bulls (n = 10). Feces were collected individually from each animal (animals without disease symptoms were selected), living on the same environmental conditions. The analysis of the results in terms of species showed differences in the Firmicutes phylum level and Lactobacillaceae family between rams and bulls. Subsequently, the analysis performed for the “host effect” showed differentiation in the levels of the Bacteroidetes and Firmicutes phyla between individuals in a group and also between the groups. Conclusion The obtained results suggest that, apart from the diet and the environment, the species and the individual host are equally important factors influencing the microbiological composition of the digestive system of ruminants.

Peakedness of Wave Systems Observed on the French Wave Energy Test Site (SEM-REV) Using a Spectral Partitioning Algorithm

2013 ◽  
Author(s):  
Jean-Baptiste Saulnier ◽  
Izan Le Crom
Keyword(s):  
Wave Energy ◽  
Test Site ◽  
Extreme Conditions ◽  
Multiple Wave ◽  
Wave Energy Converters ◽  
Marine Energy ◽  
Partitioning Algorithm ◽  
Spectral Partitioning ◽  
The Individual ◽  
Energy Converters

Located off the Guérande peninsula, SEM-REV is the French maritime facility dedicated to the testing of wave energy converters and related components. Lead by Ecole Centrale de Nantes through the LHEEA laboratory, its aim is to promote research alongside the development of new offshore technologies. To this end, the 1km2, grid-connected zone is equipped with a comprehensive instruments network sensing met-ocean processes and especially waves, with two identical directional Waverider buoys deployed on the site since 2009. For the design of moored floating structures and, a fortiori, floating marine energy converters, the knowledge of the main wave resource — for regular operation — but also extreme conditions — for moorings and device survivability — has to be as precise as possible. Also, the consideration of the multiple wave systems (swell, wind sea) making up the sea state is a key asset for the support of developers before and during the testing phase. To this end, a spectral partitioning algorithm has been implemented which enables the individual characterisation of wave systems, in particular that of their spectral peakedness which is especially addressed in this work. Peakedness has been shown to be strongly related to the groupiness of large waves and is defined here as the standard JONSWAP’s peak enhancement factor γ. Statistics related to this quantity are derived from the measurement network, with a particular focus on the extreme conditions reported on SEM-REV (Joachim storm).

scholarly journals Complex Concentrated Alloys for Substitution of Critical Raw Materials in Applications for Extreme Conditions

Materials ◽  
2021 ◽  
Vol 14 (5) ◽  
pp. 1197
Author(s):  
Dumitru Mitrica ◽  
Ioana Cristina Badea ◽  
Beatrice Adriana Serban ◽  
Mihai Tudor Olaru ◽  
Denisa Vonica ◽  
...  
Keyword(s):  
Raw Materials ◽  
Extreme Environment ◽  
Extreme Conditions ◽  
The European Union ◽  
Critical Metals ◽  
Research Directions ◽  
Level Of Involvement ◽  
General Evaluation ◽  
Critical Metal ◽  
Critical Raw Materials

The paper is proposing a mini-review on the capability of the new complex concentrated alloys (CCAs) to substitute or reduce the use of critical raw materials in applications for extreme conditions. Aspects regarding the regulations and expectations formulated by the European Union in the most recent reports on the critical raw materials were presented concisely. A general evaluation was performed on the CCAs concept and the research directions. The advantages of using critical metals for particular applications were presented to acknowledge the difficulty in the substitution of such elements with other materials. In order to establish the level of involvement of CCAs in the reduction of critical metal in extreme environment applications, a presentation was made of the previous achievements in the field and the potential for the reduction of critical metal content through the use of multi-component compositions.

scholarly journals Divergent mechanism regulating fluid intake and metabolism by the brain renin-angiotensin system

2012 ◽  
Vol 302 (3) ◽  
pp. R313-R320 ◽  
Author(s):  
Curt D. Sigmund
Keyword(s):  
Blood Pressure ◽  
Fluid Intake ◽  
Renin Angiotensin System ◽  
Metabolic Effects ◽  
Angiotensin System ◽  
Renin Angiotensin ◽  
Intracellular Form ◽  
Efferent Pathways ◽  
The Brain ◽  
Pituitary Adrenal Axis

The purpose of this review is two-fold. First, I will highlight recent advances in our understanding of the mechanisms regulating angiotensin II (ANG II) synthesis in the brain, focusing on evidence that renin is expressed in the brain and is expressed in two forms: a secreted form, which may catalyze extracellular ANG I generation from glial or neuronal angiotensinogen (AGT), and an intracellular form, which may generate intracellular ANG in neurons that may act as a neurotransmitter. Second, I will discuss recent studies that advance the concept that the renin-angiotensin system (RAS) in the brain not only is a potent regulator of blood pressure and fluid intake but may also regulate metabolism. The efferent pathways regulating the blood pressure/dipsogenic effects and the metabolic effects of elevated central RAS activity appear different, with the former being dependent upon the hypothalamic-pituitary-adrenal axis, and the latter being dependent upon an interaction between the brain and the systemic (or adipose) RAS.

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