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Stress (biology)

Stress (biology)
Walter Cannon used it in 1926 to refer to external factors that disrupted what he called homeostasis.[2] But "...stress as an explanation of lived experience is absent from both lay and expert life narratives before the 1930s".[3] Physiological stress represents a wide range of physical responses that occur as a direct effect of a stressor causing an upset in the homeostasis of the body. Upon immediate disruption of either psychological or physical equilibrium the body responds by stimulating the nervous, endocrine, and immune systems. The reaction of these systems causes a number of physical changes that have both short and long term effects on the body. Homeostasis is a concept central to the idea of stress. The ambiguity in defining this phenomenon was first recognized by Hans Selye (1907-1982) in 1926. Human brain (hypothalamus=red, amygdala=green, hippocampus/fornix=blue, pons=gold, pituitary gland=pink) The Spinal Cord Human spinal cord Adrenal gland Peripheral nervous system (PNS) Related:  stress

Why Zebras Don't Get Ulcers 1994 book by Robert Sapolsky Why Zebras Don't Get Ulcers is a 1994 (2nd ed. 1998, 3rd ed. 2004) book by Stanford University biologist Robert M. Sapolsky. The book proclaims itself as a "Guide to Stress, Stress-Related Diseases, and Coping" on the front cover of its third and most recent edition. Background and synopsis[edit] The title derives from Sapolsky's idea that for animals such as zebras, stress is generally episodic (e.g., running away from a lion), while for humans, stress is often chronic (e.g., worrying about losing one's job).[1] Therefore, many wild animals are less susceptible than humans to chronic stress-related disorders such as ulcers, hypertension, decreased neurogenesis and increased hippocampal neuronal atrophy. Why Zebras Don't Get Ulcers explains how social phenomena such as child abuse and the chronic stress of poverty affect biological stress, leading to increased risk of disease and disability. Reception[edit] The book received mostly positive reviews.

Stress Management Group Activities Stress, in and of itself, is not good or bad. It can be motivating. It can also be physically and psychologically harmful. The effect of stress is determined by your reaction to it so learning to manage it is a necessity. Activity #1: Have a Treasure Hunt Treasure hunts are a fun way to have groups work in smaller teams, teach problem-solving skills, and introduce a little friendly competition. Purpose Treasure hunts can strengthen relationships, foster teamwork, and help new members fit in. Design There are many possibilities when it comes to designing a treasure hunt. Having to figure out riddles to find the next clue Having to find a list of objects (or specific information) within a certain area Materials You'll need the following materials for this activity. Paper/pen for clues A prize for the winning team Instructions Here is an example of a clue-focused treasure hunt. Decide the geographic scope of the hunt. Alternate Method Activity #2: Play With Stress Balls Meditation can help by:

Universal stress protein The universal stress protein (USP) domain is a superfamily of conserved genes which can be found in bacteria, archaea, fungi, protozoa and plants.[2] Proteins containing the domain are induced by many environmental stressors such as nutrient starvation, drought, extreme temperatures, high salinity, and the presence of uncouplers, antibiotics and metals.[2] Function[edit] The protein structure of a Universal Stress Protein found in Haemophylus influenzae[4] The primary function of this superfamily is to protect the organism from environmental stress such as exposure to UV light, which may induce genes containing the USP domain in order to protect the DNA and more generally the cell from further damage.[2] During bacterial starvation the USP genes upregulated will often arrest cell growth and promote its metabolism to adapt to sparse nutrients.[2] Evolution[edit] Structure[edit] Bacteria[edit] Much of the research into USP is done on bacteria, specifically E. coli (Strain K-12). Plants[edit]

The Science of Stress We all experience stress. Even the most seemingly Zen-like person, with not a worry in the world, has experienced stress. I can assure you that stress is an innate emotion, which everyone experiences from time to time. While there are many definitions of stress, I like to think of it as something that disturbs homeostasis.1 Stress is not something that we should try to avoid as if it were some sort of unhealthy food. Where Does Stress Come From? Stress primarily develops from two sources: external and internal. <a href=" src=" alt="The Most Common Sources of Stress" border="0" /></a><br />Source: <a href=" Blog</a> Close Embed Image Stress and Time Stress can come on quickly, like when you find out you have a pop quiz in five minutes, or it can linger in the back of your mind for weeks, like when preparing for an important business meeting. Sources:

Surgical stress Systemic response to surgical injury Surgical stress is the systemic response to surgical injury and is characterized by activation of the sympathetic nervous system, endocrine responses as well as immunological and haematological changes.[1][2][3][4][5] Measurement of surgical stress is used in anaesthesia, physiology and surgery. Analysis of the surgical stress response can be used for evaluation of surgical techniques and comparisons of different anaesthetic protocols. Moreover, they can be performed both in the intraoperative or postoperative period. Similarly, a group of patients can be subjected to a surgical procedure where one anaesthetic protocol is used, and another group of patients are subjected to the same surgical procedure but with a different anaesthetic protocol. It is generally considered or hypothesized that a more invasive surgery, with extensive tissue trauma and noxious stimuli, triggers a more significant stress response.[30][31][32][33][34][35] Methods[edit]

The Fight or Flight Response - What is the "fight or flight response?" This fundamental physiologic response forms the foundation of modern day stress medicine. The "fight or flight response" is our body's primitive, automatic, inborn response that prepares the body to "fight" or "flee" from perceived attack, harm or threat to our survival. What happens to us when we are under excessive stress? When we experience excessive stress—whether from internal worry or external circumstance—a bodily reaction is triggered, called the "fight or flight" response. What are the signs that our fight or flight response has been stimulated (activated)? When our fight or flight response is activated, sequences of nerve cell firing occur and chemicals like adrenaline, noradrenaline and cortisol are released into our bloodstream. When our fight or flight system is activated, we tend to perceive everything in our environment as a possible threat to our survival. What is our fight or flight system designed to protect us from? Yes. 1. 1.

SIDD The computational model itself calculates the probability profile of a given base-pair sequence of DNA to denature, as well as the energy profile of sequence. It is through this energy profile that the technique derives its name: base pairs at lower energies are less stable (destabilized) than those of higher energies and more likely to denature. Stress related to the linking number (specifically its twist component) of the DNA causes the destabilization of the double helix (duplex); hence, Stress-Induced Duplex Destabilization. Applet[edit] Craig Benham has also developed an online applet that calculates the SIDD profile of input DNA sequences.[3] It also shows the probability profile for the given base pair sequence to denature, as well as counting the number and location of denaturation runs. References[edit] External links[edit]

7 Facts About Sugar and Depression: Is There a Connection? Image by Brook Lark Food can have many effects on your mood and emotions. When you’re hungry and want food, you can be grumpy, upset, or even angry. When you’ve had a delicious meal, you may feel elated and euphoric. The food you eat can also have long-term implications for your health. Specifically, eating too much sugar may increase your risk for mood disorders, including depression. Sugar occurs naturally in complex carbohydrates like fruits, vegetables, and grains. Eating too many simple sugars may increase your risk for depression, mood disorders, and several chronic health issues. Researchers in London discovered that a diet rich in whole foods like fruits, vegetables, and fish, can lower your risk for depression in middle age. You already know you should eat plenty of fruits, vegetables, and fish for heart and brain health and to help ward off chronic diseases. A study done in rats found that the brain’s sweet receptors are not adapted to constant and high levels of sugar. 1. 3.

Roseto effect The Roseto effect is the phenomenon by which a close-knit community experiences a reduced rate of heart disease. The effect is named for Roseto, Pennsylvania. The Roseto effect was first noticed in 1961 when the local Roseto doctor encountered Stewart Wolf, then head of Medicine of the University of Oklahoma, and they discussed, over a couple of beers, the unusually low rate of myocardial infarction in the Italian American community of Roseto compared with other locations.[1][2][3] Many studies followed, including a 50-year study comparing Roseto to nearby Bangor. As the original authors had predicted, as the Roseto cohort shed their Italian social structure and became more Americanized in the years following the initial study, heart disease rates increased, becoming similar to those of neighboring towns.[4] From 1954 to 1961, Roseto had nearly no heart attacks for the otherwise high-risk group of men 55 to 64, and men over 65 had a death rate of 1% while the national average was 2%.

How a 4th-century Taoist concept is treating anxiety While the Tao Te Ching is not one of the world’s most discussed religious texts, at least relative to the amount of attention the Bible, Quran, and Buddhist and Hindu doctrines receive, Laozi’s slim volume of instructions has massively influenced how we think about Eastern philosophy. The basis of Taoism is embedded in his series of short and punchy ideas that are rooted in, at times, paradoxical thinking. Consider one of his most famous aphorisms: “The Tao does nothing, and yet nothing is left undone.” As with those who believe meditation is “doing nothing,” wu-wei is not an easily graspable concept when approached from a mindset of constant action, i.e. the perpetual distraction our brains (and by extension, technology) afford us. Wu-wei as “not forcing” is what we mean by going with the grain, rolling with the punch, swimming with the current, trimming sails to the wind, taking the tide at its flood, and stooping to conquer. Hobson uses the “triad test” to make this point:

Maternal fetal stress transfer Maternal fetal stress transfer describes the physiological phenomenon by which psychosocial stress experienced by a mother during her pregnancy can be transferred to the fetus. Psychosocial stress (or simply social stress) describes the brain's physiological response to perceived social threat. Because of a link in blood supply between a mother and fetus, it has been found that stress can leave lasting effects on a developing fetus, even before a child is born. Mechanism of action[edit] Cortisol is type of hormone called a glucocorticoid, which glucose usage in the body and tends to be activated during a fight-or-flight response. In the case of a pregnant woman, the release of cortisol from the adrenal glands also has an effect on the fetus being carried in the womb. In cases of very high levels of maternal cortisol, this placental enzyme’s expression and activity are greatly reduced, thus buffering the fetus less from the mother’s high cortisol levels. Etiology[edit] Alcohol[edit]

Brain, The Immune System And Stress: Ultimately Connected, New Studies Suggest Colorful abstract background blur motion with bokeh lightGetty Something we all are faced with is stress, especially during the end of the year when we have deadlines to meet, along with the numerous responsibilities during the holiday season. A report put out by the American Institute of Stress, found that about 80% of workers feel stress on the job, with 40% feeling that their “job is very or extremely stressful.” This is due to the fact that the workforce landscape has changed and, as a result, many workplaces are attempting to mitigate stress. For a long time it has been thought that the brain and the immune system are two separate entities that exist in different realms. Scientists have found that immune system supports the brain during times of psychological distress. Findings of this research suggest that stress is not merely a psychological state experienced by the brain, rather the immune system plays a role in communicating with the brain and supporting us in times of stress.

Freezing behavior Reaction to specific stumuli Physiology[edit] Studies suggest that specific areas of the brain are known to either elicit or inhibit (in the case of lesions) freezing behavior in subjects. The regions include the basolateral amygdala and the hippocampus. One such study, conducted by Ann E. Another study, conducted by Gisquet-Verrier et al., tested the effects of the hippocampus, in three experiments, on both the freezing behavior and avoidance.[3] The rats were lesioned with ibotenic acid, and were tested against a control group. Neurotransmitters[edit] It has been experimentally tested that particular areas of the brain are involved with freezing behavior. Serotonin[4]Antipsychotic Drugs[5]Methamphetamine[6]Monoamine oxidase inhibitors[7] Hashimoto et al. investigated the effects of conditioned fear on serotonin and freezing behavior in rats.[4] Through in vivo microdialysis, certain concentrations of extracellular serotonin in the rat brain were able to be measured. Hormones[edit]