Academic literature on the topic 'Physiological protective mechanisms'
Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles
Consult the lists of relevant articles, books, theses, conference reports, and other scholarly sources on the topic 'Physiological protective mechanisms.'
Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.
You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.
Journal articles on the topic "Physiological protective mechanisms"
1
Souness, Graham W., Katherine Myles, and David J. Morris. "Other physiological considerations of protective mechanisms of mineralocorticoid action." Steroids 59, no. 2 (1994): 142–47. http://dx.doi.org/10.1016/0039-128x(94)90092-2.
Full text
2
Romanova, I. V., E. V. Mikhaylova, and A. L. Mikhrina. "Melanocortine system of verbinal brain: physiological mechanisms and protective properties." Журнал эволюционной биохимии и физиологии 56, no. 7 (2020): 791. http://dx.doi.org/10.31857/s004445292007236x.
Full text
3
Hoff, Julian T. "Cerebral protection." Journal of Neurosurgery 65, no. 5 (1986): 579–91. http://dx.doi.org/10.3171/jns.1986.65.5.0579.
Full textAbstract:
✓ Cerebral protection from an ischemic/hypoxic insult implies that tissue injury can be controlled or even prevented by certain therapeutic maneuvers. For example, physiological thresholds may be altered so that tissue vulnerability to the insult is reduced, or the intensity of an insult may be blunted by enhancing brain homeostasis. Such a therapeutic maneuver is carotid endarterectomy to improve blood flow in the disordered hemisphere. Alternatively, drugs with protective properties can be used before or even after the insult to “stabilize” injured tissue and prevent the harmful secondary effects that often follow. Various past and present approaches to cerebral protection employing physiological, pharmacological, and surgical intervention are reviewed. The mechanisms by which each allegedly protects the brain from ischemia and hypoxia are discussed briefly. Promising, but not always successful, approaches used in the past have pointed the way for new and more rational therapies. Truly effective protection of the brain from ischemia and hypoxia depends directly upon our capability to explore basic mechanisms of injury and our willingness to measure accurately and objectively the outcome of newly developed protective measures.
4
Carrillo-Mora, Paul, Rogelio Luna, and Laura Colín-Barenque. "Amyloid Beta: Multiple Mechanisms of Toxicity and Only Some Protective Effects?" Oxidative Medicine and Cellular Longevity 2014 (2014): 1–15. http://dx.doi.org/10.1155/2014/795375.
Full textAbstract:
Amyloid beta (Aβ) is a peptide of 39–43 amino acids found in large amounts and forming deposits in the brain tissue of patients with Alzheimer’s disease (AD). For this reason, it has been implicated in the pathophysiology of damage observed in this type of dementia. However, the role of Aβin the pathophysiology of AD is not yet precisely understood. Aβhas been experimentally shown to have a wide range of toxic mechanismsin vivoandin vitro, such as excitotoxicity, mitochondrial alterations, synaptic dysfunction, altered calcium homeostasis, oxidative stress, and so forth. In contrast, Aβhas also shown some interesting neuroprotective and physiological properties under certain experimental conditions, suggesting that both physiological and pathological roles of Aβmay depend on several factors. In this paper, we reviewed both toxic and protective mechanisms of Aβto further explore what their potential roles could be in the pathophysiology of AD. The complete understanding of such apparently opposed effects will also be an important guide for the therapeutic efforts coming in the future.
5
Prokopchook, V. S., and A. V. Lyckbäck. "Basis of the general theory of pathology (Part 3. Sepsis as an adaptive protective response of organism)." Likarska sprava, no. 7-8 (December 30, 2018): 4–11. http://dx.doi.org/10.31640/jvd.7-8.2018(1).
Full textAbstract:
A problem of the essence of sepsis remains unresolved. Sepsis isseen as inadequate, insufficient, or perverted body's response to microbial invasion. The authors analyze the problem of sepsis from the opposite (paradoxical) position based on the well-known postulate that any pathological process (disease) is an adaptation i. e. a protective mechanism. The authors describe known antimicrobial protective barriers ("physiological" and "pathological") and determine a role of different variants of sepsis in protective reactions of human body. The article describes the nature and mechanisms of adaptation under the different variants of sepsis: Wissler – Fanconi’ssubsepsis, intravascular infection, septicopyemia, septicemia and septic shock. These mechanisms might form the basis of pathogenetic therapy. The authors believe that a degree of effectiveness of "pathological" protection of the internal environment is determined by time, i. e. by a duration of a protective effect. In the launch of a septic reaction an important role belongs to a massive invasion of microorganisms into the internal environment of a host by unnatural way – bypassing protective barriers created by evolution. Thus, from the authors' point of view, sepsis is a general pathological process ("pure" infection). Sepsis is a non-specific adaptive (defensive) reaction of human body to a massive microbial invasion.
6
Prokopchook, V. S., and A. V. Lyckbäck. "Basis of the general theory of pathology (Part 3. Sepsis as an adaptive protective response of organism)." Likarska sprava, no. 7-8 (December 30, 2018): 4–11. http://dx.doi.org/10.31640/vd.7-8.2018(1).
Full textAbstract:
A problem of the essence of sepsis remains unresolved. Sepsis isseen as inadequate, insufficient, or perverted body's response to microbial invasion. The authors analyze the problem of sepsis from the opposite (paradoxical) position based on the well-known postulate that any pathological process (disease) is an adaptation i. e. a protective mechanism. The authors describe known antimicrobial protective barriers ("physiological" and "pathological") and determine a role of different variants of sepsis in protective reactions of human body. The article describes the nature and mechanisms of adaptation under the different variants of sepsis: Wissler – Fanconi’ssubsepsis, intravascular infection, septicopyemia, septicemia and septic shock. These mechanisms might form the basis of pathogenetic therapy. The authors believe that a degree of effectiveness of "pathological" protection of the internal environment is determined by time, i. e. by a duration of a protective effect. In the launch of a septic reaction an important role belongs to a massive invasion of microorganisms into the internal environment of a host by unnatural way – bypassing protective barriers created by evolution. Thus, from the authors' point of view, sepsis is a general pathological process ("pure" infection). Sepsis is a non-specific adaptive (defensive) reaction of human body to a massive microbial invasion.
7
Babichev, Anatoliy Vasilyevich. "The role of endothelium in hemostasis mechanisms." Pediatrician (St. Petersburg) 4, no. 1 (2013): 122–27. http://dx.doi.org/10.17816/ped41122-127.
Full textAbstract:
Formation and excretion of thrombogenous and athrombogenous factors by endothelial cells is a constant physiological process taking place in all vessels. Endothelium is a huge endocrine gland which generates a wide spectrum of biologically active substances. Biologically active substances of endothelium are involved in many hemostasis mechanisms and regulation of local blood flow. BAS composition is determined by status of endothelial cells. In physiological state BAS of endothelium provide adequate local blood flow by synthesizing powerful anticoagulants, vasodilators and other biologically active substances. Activity of endothelium in physiological conditions provides trophism of tissues and fulfils protective function. Disturbance of any function or structure of endothelium significantly changes the spectrum of biologically active substances. Endothelium starts to secrete aggregants, coagulants, vasoconstrictors and other factors many of which contribute to generalization of the pathological process.
8
Notariale, Rosaria, Pasquale Perrone, Luigi Mele, Gennaro Lettieri, Marina Piscopo, and Caterina Manna. "Olive Oil Phenols Prevent Mercury-Induced Phosphatidylserine Exposure and Morphological Changes in Human Erythrocytes Regardless of Their Different Scavenging Activity." International Journal of Molecular Sciences 23, no. 10 (2022): 5693. http://dx.doi.org/10.3390/ijms23105693.
Full textAbstract:
Phosphatidylserine (PS) translocation to the external membrane leaflet represents a key mechanism in the pathophysiology of human erythrocytes (RBC) acting as an “eat me” signal for the removal of aged/stressed cells. Loss of physiological membrane asymmetry, however, can lead to adverse effects on the cardiovascular system, activating a prothrombotic activity. The data presented indicate that structurally related olive oil phenols prevent cell alterations induced in intact human RBC exposed to HgCl2 (5–40 µM) or Ca2+ ionophore (5 µM), as measured by hallmarks including PS exposure, reactive oxygen species generation, glutathione depletion and microvesicles formation. The protective effect is observed in a concentration range of 1–30 µM, hydroxytyrosol being the most effective; its in vivo metabolite homovanillic alcohol still retains the biological activity of its dietary precursor. Significant protection is also exerted by tyrosol, in spite of its weak scavenging activity, indicating that additional mechanisms are involved in the protective effect. When RBC alterations are mediated by an increase in intracellular calcium, the protective effect is observed at higher concentrations, indicating that the selected phenols mainly act on Ca2+-independent mechanisms, identified as protection of glutathione depletion. Our findings strengthen the nutritional relevance of olive oil bioactive compounds in the claimed health-promoting effects of the Mediterranean Diet.
9
King, Michelle A., Ian Rollo, and Lindsay B. Baker. "Nutritional considerations to counteract gastrointestinal permeability during exertional heat stress." Journal of Applied Physiology 130, no. 6 (2021): 1754–65. http://dx.doi.org/10.1152/japplphysiol.00072.2021.
Full textAbstract:
Intestinal barrier integrity and function are compromised during exertional heat stress (EHS) potentially leading to consequences that range from minor gastrointestinal (GI) disturbances to fatal outcomes in exertional heat stroke or septic shock. This mini-review provides a concise discussion of nutritional interventions that may protect against intestinal permeability during EHS and suggests physiological mechanisms responsible for this protection. Although diverse nutritional interventions have been suggested to be protective against EHS-induced GI permeability, the ingestion of certain amino acids, carbohydrates, and fluid per se is potentially effective strategy, whereas evidence for various polyphenols and pre/probiotics is developing. Plausible physiological mechanisms of protection include increased blood flow, epithelial cell proliferation, upregulation of intracellular heat shock proteins, modulation of inflammatory signaling, alteration of the GI microbiota, and increased expression of tight junction (TJ) proteins. Further clinical research is needed to propose specific nutritional candidates and recommendations for their application to prevent intestinal barrier disruption and elucidate mechanisms during EHS.
10
Bao, Naren, and Bing Tang. "Organ-Protective Effects and the Underlying Mechanism of Dexmedetomidine." Mediators of Inflammation 2020 (May 9, 2020): 1–11. http://dx.doi.org/10.1155/2020/6136105.
Full textAbstract:
Dexmedetomidine (DEX) is a highly selective α2 adrenergic receptor (α2AR) agonist currently used in clinical settings. Because DEX has dose-dependent advantages of sedation, analgesia, antianxiety, inhibition of sympathetic nervous system activity, cardiovascular stabilization, and significant reduction of postoperative delirium and agitation, but does not produce respiratory depression and agitation, it is widely used in clinical anesthesia and ICU departments. In recent years, much clinical study and basic research has confirmed that DEX has a protective effect on a variety of organs, including the nervous system, heart, lungs, kidneys, liver, and small intestine. It acts by reducing the inflammatory response in these organs, activating antiapoptotic signaling pathways which protect cells from damage. Therefore, based on wide clinical application and safety, DEX may become a promising clinical multiorgan protection drug in the future. In this article, we review the physiological effects related to organ protection in α2AR agonists along with the organ-protective effects and mechanisms of DEX to understand their combined application value.
Dissertations / Theses on the topic "Physiological protective mechanisms"
1
Randle, Laura Elizabeth. "Pharmacological and physiological protective mechanisms in chemical-induced hepatotoxicity." Thesis, University of Liverpool, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.420287.
Full text
2
沈毅峰 and Ngai-fung Sham. "Study of the protective mechanisms of cigarette smoke and nicotine on experimental ulcerative colitis in rats." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2001. http://hub.hku.hk/bib/B31225081.
Full text
3
Янчик, Галина Володимирівна, Галина Владимировна Янчик, Halyna Volodymyrivna Yanchyk, Вікторія Юріївна Гарбузова, Виктория Юрьевна Гарбузова та Viktoriia Yuriivna Harbuzova. "Психофізіологічні механізми захисту організму людей". Thesis, Вид-во СумДУ, 2005. http://essuir.sumdu.edu.ua/handle/123456789/6498.
Full text
4
Makarov, S. Y., O. Y. Panchuk, and I. V. Serheta. "Educational stress and mechanisms of psychological protection of student youth: problematic issues, physiological and hygienic aspects." Thesis, Sumy State University, 2017. http://essuir.sumdu.edu.ua/handle/123456789/63256.
Full textAbstract:
During the research the physiological and hygienic features of changes in the
leading characteristics of the mechanisms of psychological protection of students
who are in the conditions of educational stress in a higher medical educational
institution are determined.
Books on the topic "Physiological protective mechanisms"
1
Canlon, Barbara. The effect of acoustic trauma on the tectorial membrane, stereocilia, and hearing sensitivity: Possible mechanisms underlying damage, recovery, and protection. Distributed by Almqvist & Wiksell Periodical Co., 1988.
Find full text
2
Riegger, Lieselotte. UV-Schutz- und Reparaturmechanismen bei antarktischen Diatomeen und Phaeocystis antarctica =: Mechanisms of UV protection and repair in Antarctic diatoms and Phaeocystis antarctica. Alfred-Wegener-Institut für Polar- und Meeresforschung, 2001.
Find full text
3
Laffey, John G., and Brian P. Kavanagh. Hypercapnia in the critically ill. Oxford University Press, 2016. http://dx.doi.org/10.1093/med/9780199600830.003.0086.
Full textAbstract:
Hypercapnia is a central component of current ‘protective’ ventilator management. Hypercapnia, and the associated acidosis, has potentially important biologic effects on immune responses, injury and repair. Arterial carbon dioxide tension PaCO2 is tightly governed under physiological conditions and small elevations rapidly increase spontaneous minute ventilation. In the mechanically-ventilated patient, elevated PaCO2 usually reflects reduced elimination. This can be because tidal volume or respiratory rate delivered by the ventilator are reduced, or because of the diseased lung per se. Hypercapnia has many effects that are clinically obvious, but research over the last decade reveals important consequences on inflammatory and cellular mechanisms that are not apparent at the bedside.
4
Lumb, Andrew B., and Natalie Drury. Respiratory physiology in anaesthetic practice. Edited by Jonathan G. Hardman. Oxford University Press, 2017. http://dx.doi.org/10.1093/med/9780199642045.003.0002.
Full textAbstract:
Moving away from the structure of traditional texts, this chapter follows the journey of oxygen molecules as they move from inspired air to their point of use in mitochondria, with some digressions along the way to cover other relevant aspects of respiratory physiology. The chapter encompasses all the key aspects of respiratory physiology and also highlights physiological alterations that occur under both general and regional anaesthesia, moving the physiological principles discussed into daily anaesthetic practice. The chapter explores relevant anatomy of the airways, lungs, and pleura. The histology and function of the airway lining and alveoli are described, so illustrating the importance of pulmonary defence mechanisms for protecting the internal milieu of the body from this large and fragile interface with the outside world. Key principles and concepts including resistance, compliance, and diffusion are all discussed in their clinical context. Concepts relating to the mechanics of breathing and the control of airway diameter are considered along with lung volumes and their measurement. Both the central and peripheral mechanisms involved in the control of breathing are discussed with particular attention to the impact of anaesthesia. The relationship between ventilation and perfusion and the carriage of oxygen and carbon dioxide are all discussed in detail. The principles behind key respiratory measurements such as dead space, lung volumes, diffusing capacity, and shunt are all described. Overall the chapter provides a comprehensive review of respiratory physiology as well as including additional aspects of variation that occur under anaesthesia.
5
Trigo Blanco, Paula, Maricarmen Roche Rodriguez, and Nalini Vadivelu. Pathophysiology of Pain and Pain Pathways. Oxford University Press, 2018. http://dx.doi.org/10.1093/med/9780190626761.003.0001.
Full textAbstract:
Pain is a distressing experience and an important cause of suffering and disability. Pain usually signals the presence of injury or disease and generates a complex physiologic and emotional response. It has a protective function in order to restore homeostasis at the autonomic and psychological levels. This chapter reviews the physiology and mechanisms of pain, as well as the pathways in the central and peripheral nervous system that transmit nociceptive information. The chapter divides the pain anatomical pathways into the peripheral nervous system, the spinal cord with the medullary dorsal horn system, and the ascending and supraspinal system. The authors explain the pain pathways as a three-neuron pathway that carries noxious information from the periphery to the cerebral cortex. This chapter defines important concepts such as sensitization, hyperalgesia, and allodynia, as well as describes the modulation process of nociception.
9
Factors Affecting The Removal Of Ammonia From Air On Carbonaceous Materials Investigation Of Reactive Adsorption Mechanism. Springer, 2012.
Find full text
10
Sabri, Omar, and Martin Bircher. Management of limb and pelvic injuries. Oxford University Press, 2016. http://dx.doi.org/10.1093/med/9780199600830.003.0336.
Full textAbstract:
Pelvic ring injuries can be life and limb threatening. The mechanism of injury can often be a good indicator of the type of injury; the Young & Burgess classification deploys that concept to full effect. Early identification based on mechanism of injury and improved prehospital care can play a major role in the outcome following such injuries. Pelvic ring injuries can lead to significant haemorrhage. Mechanical measures to stabilize the pelvis, in addition to modern concepts of damage control resuscitation (DCR), have been shown to be effective in early management of potentially life-threatening haemorrhage. Emphasis is now entirely on protecting the primary clot following a pelvic ring injury. Mechanical disturbance by log rolling the patient or springing of the pelvis are strongly discouraged. Early radiological clearance of the pelvis is encouraged. The lethal triad of coagulopathy, acidosis, and hypothermia should be corrected simultaneously to improve outcome. A traffic light system for monitoring venous lactate as an indicator of the patients’ physiological state can help the intensive care practitioner and the surgeon identify optimum timing for surgery. Pelvic ring injuries are associated with significant concomitant injuries. Limb trauma can also be life or limb threatening. Early identification, splinting, and resuscitation follow the same guidelines as pelvic ring injuries. Open long bone fractures should be managed by senior orthopaedic and plastic surgeons.
Book chapters on the topic "Physiological protective mechanisms"
1
Sağlam, Aykut, and Sumira Jan. "Importance of Protective Compounds in Stress Tolerance." In Physiological Mechanisms and Adaptation Strategies in Plants Under Changing Environment. Springer New York, 2013. http://dx.doi.org/10.1007/978-1-4614-8600-8_9.
Full text
2
Perez, Maritza I., Richard L. Edelson, Yasuhiro Yamane, and Francis M. Lobo. "A Murine T-Cell Lymphoma Model Showing Protection Against Tumor Development and Treatment of Established Disease." In Basic Mechanisms of Physiologic and Aberrant Lymphoproliferation in the Skin. Springer US, 1994. http://dx.doi.org/10.1007/978-1-4615-1861-7_40.
Full text
3
Bauer, Moises E., Natália P. Rocha, Wilson Savino, and Antonio L. Teixeira. "Immune Mechanisms Affecting the Functioning of the Central Nervous System (CNS)." In Immunopsychiatry. Oxford University Press, 2018. http://dx.doi.org/10.1093/med/9780190884468.003.0003.
Full textAbstract:
This chapter presents an overview of the immune mechanisms affecting the functioning of the central nervous system (CNS). The cross-talk between the immune system and the CNS is established by three independent pathways: the humoral, neural, and cellular (leukocyte) routes. Of note, increased circulating pro-inflammatory cytokines and concomitant activation of brain-resident microglia can lead to impaired cognition and depressive behavioral symptoms. The activated microglia phenotype has been associated with neuroinflammation reported in neurodegenerative and psychiatric disorders. This chapter also reviews novel physiological roles for adaptive immunity (especially T cells) during health and disease. T cells support hippocampal neurogenesis, cognition, mood, resilience to stress, and are protective against the development of psychiatric disorders.
4
Lamb, Chris. "Prospects for Engineering Enhanced Durable Disease Resistance in Crops." In Feeding a World Population of More Than Eight Billion People. Oxford University Press, 1998. http://dx.doi.org/10.1093/oso/9780195113129.003.0020.
Full textAbstract:
Plants have evolved a battery of defense mechanisms that in aggregate provide protection against a wide range of potential viral, bacterial, fungal, and other pathogens encountered throughout the plant life cycle. However, in the artificial setting of agriculture, disease, although the exception, can be costly and even devastating. Crop diseases have played significant roles in human history, exemplified by the widespread starvation and mass emigration triggered by the failure of European potato crops in the mid-nineteenth century as a result of late blight. Today, the use of pesticides, breeding for resistance, and integrated pest management provide important tools for reducing crop losses to pre-and postharvest diseases. However, agrichemicals are expensive, prohibitively so for many fanners in developing countries, and there are increasing concerns about environmental load from their intensive application. Likewise, major disease resistance (R) genes are in many cases not durable, resistance breaking down within one or two seasons as a result of selection pressure on the pathogen population, and most breeding efforts now rely on combinations of minor resistance genes, each giving partial protection. For a number of important diseases, such as take-all of wheat, there is no effective genetic resistance. Population growth, migration to cities, desertification, and climate change all now contribute to an urgent need to secure diversified food production against disease losses. In this chapter I discuss the prospects that genetic engineering of disease-resistance mechanisms can contribute to durable, broad protection and hence underpin enhanced crop productivity. Plants have a number of performed physical and chemical defensive mechanisms that help protect against the myriad potential pathogens to which plants arc exposed (Osbourn, 1996). However, superimposed upon this preexisting protective armory, plants respond to the perception of pathogen attack by activation of inducible defense mechanisms (Lamb et al., 1989; Staskawicz et al., 1995). Many of the most important crop diseases involve specialized interactions between pathogen and host. Interactions between specific plant cultivars and defined physiological races or strains of potential pathogens are described as compatible (host susceptible, pathogen virulent) or incompatible (host resistant, pathogen avirulent).
5
Ross, Edward A., Uyanga Batnyam, and Abdo M. Asmar. "Cardiorenal Syndrome." In Kidney Protection, edited by Vijay Lapsia, Bernard G. Jaar, and A. Ahsan Ejaz. Oxford University Press, 2019. http://dx.doi.org/10.1093/med/9780190611620.003.0041.
Full textAbstract:
Renal and cardiac crosstalk plays an essential role in maintaining physiological homeostasis. Both organ diseases are prevalent and share common risk factors. Impairment in one organ has the potential to affect the other. This interaction is referred to as cardiorenal syndrome, and it is driven by complex neurohumoral and vascular processes. Cardiorenal syndrome refers to a state of either acute or chronic impairment of both renal and cardiac functions. Despite progress in therapeutic interventions, treatment of cardiorenal syndrome remains challenging. In this chapter, we review the current understanding of the pathophysiological mechanisms of cardiorenal syndrome, as well as its management options.
6
Mendel Nzogang, Patrice, and Martial Boris Donkeng. "Neuroprotection: The Way of Anti-Inflammatory Agents." In Neuroprotection - New Approaches and Prospects. IntechOpen, 2020. http://dx.doi.org/10.5772/intechopen.90509.
Full textAbstract:
Neurons are basic structural and functional units of the nervous system with major function being that of integration and interpretation of neuronal input or information. The lifespan of a nerve cell generally last throughout the individual lifetime. However, some physiologic or pathologic processes may affect the neuron causing premature death of this cell or tissue. This premature neurological death caused by pathologic circumstances is what we call neurotoxicity. The biochemical mechanisms put forward to explain neurotoxicity are not fully known. Nonetheless, whatever the mechanism involved, the outcome usually results in apoptosis, pyropoptosis, or necrosis. Examples of these mechanisms include excitotoxicity, oxidative stress, glial cell destruction, vascular interruptions, and inflammation. The idea about possibly protecting neurons against insults using pharmacologic means leads to the birth of the neuroprotection concept. This new concept has emerged based on ongoing research, suggesting it is possible through physical and pharmacological means to prevent or avoid neurotoxicity by the abovementioned mechanisms but with the exception of vascular interruption mechanisms. We will present in this chapter a synoptic view of the inflammatory mechanisms implicated in neurotoxicity and bring out the possible implications in neuroprotection.
7
Kaira, Meenakshi, Abhilasha Ahlawat, Vaibhav Walia, and Munish Garg. "Autophagic Dysfunction in Neurodegeneration." In Quality Control of Cellular Protein in Neurodegenerative Disorders. IGI Global, 2020. http://dx.doi.org/10.4018/978-1-7998-1317-0.ch002.
Full textAbstract:
Autophagy is a normal physiological process characterized by the degradation of complex cellular contents into a simpler one and reutilized them in biosynthetic pathways. Lysosomes are the cell organelle that participates in the process of autophagy. The brain is the most vulnerable organ in most lysosome disorders because neurons are inefficient in removing impaired organelles and waste materials. In the brain, autophagy suppresses the accumulation of ubiquitinated proteins that results in further damage to the neurons responsible for neurodegeneration. Autophagy mediates protective effects in age-related diseases. In the chapter, the authors describe the process of autophagy, the mechanism involved, and the implication of the autophagic pathways in the various neurodegenerative disorders.
8
K. Al Sarkhi, Awaad. "The Link between Electrical Properties of COVID-19 and Electromagnetic Radiation." In Biotechnology to Combat COVID-19 [Working Title]. IntechOpen, 2021. http://dx.doi.org/10.5772/intechopen.96815.
Full textAbstract:
The ability of a new vaccine design based on control the intracellular physiological consequences of both the electrical properties and the electromagnetic radiation interactions between a virus and a host cell, which is a method to strengthen immune system develop protection against COVID-19 and new strains. The capacity of COVID-19 to bind to angiotensin-converting enzyme 2 (ACE2) and immune evasion mechanisms are only one of the properties required to stimulate a preventative immune response. In this chapter, a multidimensional new strategy is used to exemplify the empowerment function intracellular and extracellular level information can play in the support of immunogen against COVID-19 pathogens. Besides during this chapter, the nature of electromagnetic radiation is described as a vibrating string based on a string-theory and unification of electromagnetic radiation and gravitational waves by supporting with multiple cites strong evidence. Overall, we demonstrate a new approach to understand the important role of the physiological consequences of the interplay between the immune system and COVID-19 and designing vaccine strategy immunogens that take advantage of that information against COVID-19 and new strains.
9
Mahmood Shakir, Huda. "Antioxidant and Infertility." In Antioxidants - Benefits, Sources, Mechanisms of Action. IntechOpen, 2021. http://dx.doi.org/10.5772/intechopen.95791.
Full textAbstract:
Unexplained sub-fertility is commonly identified if couples fail to conceive after 1 yr. of everyday unprotected sexual intercourse even though investigations for ovulation, tubal patency and semen evaluation are ordinary. Many previous studies had shown that oxidative stress plays an important role in human fertility. Free radicals are neutralized by an elaborate antioxidant defense system. In a healthy body, pro-oxidants and antioxidants maintain a ratio and a shift in this ratio towards pro-oxidants gives rise to oxidative stress. There are two types of antioxidants in the human body: enzymatic and non-enzymatic antioxidants. Under normal conditions, antioxidants convert ROS to H2O to prevent overproduction of ROS. All cells in the human body are capable of synthesizing glutathione specially the liver. Free radicals appear to have a physiological role in female reproductive system in many different processes such as: oocyte maturation, fertilization, luteal regression, endometrial shedding and progesterone production by the corpus luteum. Protection from ROS is afforded by scavengers present in both male and female reproductive tract fluids, as well as in seminal plasma elevated concentrations of ROS in these environments may have detrimental effects on the spermatozoa, oocytes, sperm oocyte interaction and embryos both in the Fallopian tube and the peritoneal cavity; therefore oxidative stress modulates a host of reproductive pathologies affecting natural fertility in a woman’s life.
10
Bano, Ambreen, Anmol Gupta, Smita Rai, Touseef Fatima, Swati Sharma, and Neelam Pathak. "Mechanistic Role of Reactive Oxygen Species and Its Regulation Via the Antioxidant System under Environmental Stress." In Plant Stress Physiology - Perspectives in Agriculture [Working Title]. IntechOpen, 2021. http://dx.doi.org/10.5772/intechopen.101045.
Full textAbstract:
The antioxidant potential is referred to as compounds that are capable of protecting the biological system against the deleterious effect of reactions involving reactive oxygen species (ROS). ROS are toxic byproducts of oxygen metabolism. ROS have a significant role in plant signaling, growth, development, and majorly in response to environmental fluctuations. The ROS family plays a double role under various environmental stress conditions. In various key physiological phenomena, they act as secondary messengers and induce oxidative damage. ROS led to cellular damages that manifest themselves in degradation of biomolecules, which eventually amalgamate to cellular death in plants. To assure survival, plants have developed efficient antioxidant machinery having two branches, that is, an enzymatic and a nonenzymatic antioxidant. This chapter will emphasize the various types of ROS, their sites of cellular production, targets, and scavenging mechanisms mediated by antioxidants in abiotic stress. Such profound knowledge will let us build strategies against environmental stress.
Conference papers on the topic "Physiological protective mechanisms"
1
Turbina, I. N., and G. M. Kukurichkin. "ANALYSIS OF THE PIGMENT STATUS OF SOME SPECIES OF GENUS ACER L. USING THE PROGRAM STATISTICA." In Prirodopol'zovanie i ohrana prirody: Ohrana pamjatnikov prirody, biologicheskogo i landshaftnogo raznoobrazija Tomskogo Priob'ja i drugih regionov Rossii. Izdatel'stvo Tomskogo gosudarstvennogo universiteta, 2020. http://dx.doi.org/10.17223/978-5-94621-954-9-2020-56.
Full textAbstract:
The present paper is aimed at the analysis of adaptation mechanisms of five species of the genus Acer L. in the culture of the botanical garden.With this view we studied the indices of the pigment complex (nitrogen balance - Nbi, flavonols - Flv and chlorophyll - Ch) in the assimilating organs of plants. It was revealed that the pigment composition of plant leaves indicates their relatively high physiological status. An increase in biochemical parameters (Nbi,Chl, Flv) was identified by the end of summer in comparison with the beginning of summer period, which testifies to the formation of the protective function of the plant in the pre-winter period. The following statistical methods were used for test results interpretation: Shapiro – Wilk tests, Mann – Whitney, Wilcoxon, Kruskal-Wallisand criteria.
2
Ye, Changpeng, Ruoyang Chen, and Jiangang Zhao. "The photo-physiologica inhibited mechanism on typical HABs,Scrippsiella trochoidea, by seawater extraction of macroalga, Gracilaria Lemaniformis." In 2016 5th International Conference on Energy and Environmental Protection (ICEEP 2016). Atlantis Press, 2016. http://dx.doi.org/10.2991/iceep-16.2016.102.
Full text
3
Pavlovskaya, H. E., and I. N. Gagarina. "PHYSIOLOGICAL AND BIOCHEMICAL STUDY ON THE DEVELOPMENT OF BIOLOGICAL MEANS OF PROTECTION OF PLANTS FROM DISEASES." In The All-Russian Scientific Conference with International Participation and Schools of Young Scientists "Mechanisms of resistance of plants and microorganisms to unfavorable environmental". SIPPB SB RAS, 2018. http://dx.doi.org/10.31255/978-5-94797-319-8-1334-1338.
Full text
4
Lima, Rian, Carlos Silva, João Santos, and Letícia Pinheiro. "THE EFFECTS ON COGNITIVE RESERVE (CR) GENERATED BY EXERCISE IN ALZHEIMER’S DISEASE: A SYSTEMATIC REVIEW." In XIII Meeting of Researchers on Alzheimer's Disease and Related Disorders. Zeppelini Editorial e Comunicação, 2021. http://dx.doi.org/10.5327/1980-5764.rpda057.
Full textAbstract:
Background: Cognitive reserve (CR) is a concept that describes a large amount of neural changes, which come from habits, like physical activity. CR protects the brain against the development and evolution of dementia. The possible mechanisms of these changes still remain unknown, and this lack of knowledge distorts the elaboration of practices capable of amplifying this protection. Objectives: To analyze the data about how physical activity can reverberate on the nervous system, relating the effects of exercise and development of AD. Methods: Search in the Pubmed database using descriptors: “Physical activity” OR “Exercise” AND “Cognitive reserve” AND “Alzheimer”. All articles that include any physiological correlation between exercise and CR were analysed. Results: Sedentaries people had greater β-amyloid loads in the brain and lower levels of it in the cerebrospinal fluid. Furthermore, habitual physical activity may improve serum level of brain derived neurotrophic factor, a protein which is capable of enhancing synaptic plasticity and leads to the formation of new neurons in the dentate gyrus of the hippocampus. The studies also showed that aerobics exercises have a greater effect on CR, mainly if they are done in a regular form. Conclusion: Habitual physical activity can impact AD by helping the effectiveness of the treatment and delaying it´s evolution.
5
Farah, Huda Mohamed, Muram Elmubarak Elamin, Rahaf Nader Nader Nader, et al. "Metagenomic Analysis of Oral Microbiome during pregnancy." In Qatar University Annual Research Forum & Exhibition. Qatar University Press, 2021. http://dx.doi.org/10.29117/quarfe.2021.0135.
Full textAbstract:
Pregnancy is a dynamic physiological process associated with significant hormonal, immune and metabolic changes to support the growth and development of the fetus. Several studies have highlighted the role of gut microbiota during pregnancy1. The composition of gut microbiota changes dramatically during the course of pregnancy with an increase in Proteobacteria and Actinobacteria, a decline in butyrate-producing bacteria and a reduction in bacterial richness at the end of pregnancy2. These modifications were anticipated to favour the increased metabolic demand during pregnancy, which will, in turn, support healthy fetal growth3. Gut microbiota has also been suggested to contribute to weight gain during pregnancy via increased absorption of glucose and fatty acids, induction of catabolic pathways, increased fasting-induced adipocyte factor secretion, and stimulation of the immune system2, 4. The oral cavity houses the second most diverse microbiota after the gut harbouring over 700 species of bacteria. Oral microbiota plays a crucial role in maintaining oral homeostasis, protecting the oral cavity and preventing disease development5. Little is known about the role of the oral microbiome during pregnancy. One study examined changes in oral microbiota during pregnancy on Japanese women and found that the total viable microbial counts were higher during pregnancy, as were levels of the pathogenic bacteria Porphyromonas gingivalis, Aggregatibacter actinomycetemcomitans, and Candida6. Several studies have also found correlations between oral infections and pregnancy complications, further suggesting mechanisms connecting the oral microbiome with the state of pregnancy7. The Qatari Birth Cohort (QbiC) was successfully developed in July 2018 by Qatar Biobank. It is an epidemiological study that aims to assess the synergetic role of environmental exposure and genetic factors in the development of chronic disease. It monitors the health of women throughout their pregnancy and after birth. The present study is designed to explore changes in the salivary microbiome, using high throughput sequencing during pregnancy and to explore key microbial clades involved in pregnancy.
6
Comp, P. C., and C. T. Esmon. "Defects in the protein C pathway." In XIth International Congress on Thrombosis and Haemostasis. Schattauer GmbH, 1987. http://dx.doi.org/10.1055/s-0038-1643715.
Full textAbstract:
Activated protein C functions as an anticoagulant by enzymatically degrading factors Va and Villa in the clotting cascade. Protein C may be converted to its enzymatically active form bythrombin. The rate at which thrombin cleavage of the zymogen occurs is greatly enhanced when thrombin is bound to an endothelial cell receptor protein, thrombomodulin. Activated proteinC has a relatively long half-life in vivo and the formation of activated protein C in response to low level thrombin infusion suggests that the protein C system may provide a feedback mechanism to limit blood clotting. Clinical support for such a physiologic role for activated protein C includes an increased incidence of thrombophlebitis and pulmonary emboli in heterozygous deficient individuals, and severe, often fatal, cutaneous thrombosis in homozygous deficient newborns. A third thrombotic condition associated with protein C deficiency is coumarin induced skin (tissue) necrosis. This localized skin necrosis occurs shortly after the initiation of coumarin therapy and is hypothesized to bedue to the rapid disappearance of protein C activity in the plasma beforean adequate intensity of anticoagulation is achieved. Recent estimates of heterozygous protein C deficiency range as high as 1 in 300 individuals in the general population. Since coumarin compounds are in routine clinical use throughout the world and skin necrosis remains a relatively rare clinical finding, this suggests that factors other than protein C deficiency alone may be involved in the pathogenesis of the skin necrosis.The anticoagulant properties of activated protein C are greatly enhanced by another vitamin K-dependent plasma protein, protein S. Protein S functions by increasing the affinity of activated protein C for cell surfaces.Protein S is found in two forms in plasma: free and in complex with C4b-binding protein, "an inhibitor of the complement system. Free protein S is functionally active and the complexed protein S is not active. Individuals congenitally deficient in protein S ae subject to recurrent thromboembolicevents. At least two classes of protin S deficiency occur.Some patienshavedecreased levels of protein S antigen and reduced protein S functional activity. A second group of deficient individuals have normal levels of protein S antigen but most or all their protein S is complexed to C4b-binding protein and they have little or no functional protein S activity. Such a protein S distribution could result from abnormal forms of protein S or C4b-binding protein or some other abnormal plasma or cellular component. Patients with functionally inactive forms of protein S have yet to be identified. Identification of protein S deficient individuals is complicated by thepossible effect of sex hormones on plasma protein S levels. Total protein S antigen is reduced during pregnancyand during oral contraceptive administration. This finding is of practicalclinical importance since the decrease in protein S which occurs during pregnancy may be an added risk factor for congenitally protein S deficient women and may explain why some proteinS deficient women experience their first episode of thrombosis during pregnancy.In addition to having anticoagulant properties, activated protein C enhances fibrinolysis, at least in part,by inhibiting the inhibitor of tissueplasminogen activator. This profibrinolytic effect is enhanced by protein S and cell surfaces. This protection of plasminogen activator activity suggests that the combination of tissue plasminogen activator and activated protein C may be useful in the treatment of coronary artery thrombi. Tissueplasminogen activator would promote clot lysis while activated protein C protected the plasminogen activatorfrom inhibition and also prevented further clot deposition. There is no evidence at present that fibrinolytic activity is reduced in protein C deficient individuals. The possible clinical relevance of this aspect of protein Cfunction in the predisposition of protein C deficient individuals to thrombosis remains to be defined.
Reports on the topic "Physiological protective mechanisms"
1
Shahak, Yosepha, and Donald R. Ort. Physiological Bases for Impaired Photosynthetic Performance of Chilling-Sensitive Fruit Trees. United States Department of Agriculture, 2001. http://dx.doi.org/10.32747/2001.7575278.bard.
Full textAbstract:
Chilling-sensitivity is an important agricultural problem in both the U.S. and Israel. Most research attention has focused so far on herbaceous crop plants, even though the problem is also acute in the fruit tree industry. Under BARD funding we made substantial progress in identifying the mechanisms involved in the disruption of photosynthesis following a chill in mango. Our investigation with fruit trees has been substantially accelerated by drawing on our knowledge and experience with herbaceous crops. The four original research objectives, focused or discovering the underlying mechanisms of chill-induced inhibition of photosynthesis in fruit trees, and the main achievements are listed below. [1] Separating stomatal from non-stomatal components of chilling on photosynthesis in fruit trees. We found evidence that the dark chill-induced inhibition of photosynthesis in mango was E combination of both stomatal and mesophyll components. [2] Differentiating photo damage from light-induced photo protection of photosystem II (PSII). Dark chilling exacerbate high light photoinhibition, as a result of primary inhibition in the carbor reduction cycle. Nevertheless, in Israeli orchards we observed chronic photoinhibition of PSII photochemistry in the winter. This photo damage was reversible over a few days if sunlight was attenuated with filters or night temperature rose. Practical implications of this finding deserve further investment. Additional achievement was the development of a new biophysical tool to study macro-structural changes of LHCII particles in intact, attached leaves. [3] Determine the role of oxidative stress in the dark-chilling-induced inhibition, with emphasis on oxygen radical scavenging, lipid peroxidation and redox-controlled carbon-cycle enzymes. We found an increase in lipid peroxidation following a dark chill, and partial protective effects or an antioxidant. However, the photoinhibition observed in mango orchards in Israel during the winter did not appear to be a general oxidative stress. [4] Investigate whether chilling interferes with the diurnal and circadian rhythm of gene expression of key photosynthetic proteins as has been shown for chilling-sensitive crop plants. The results indicated that most of the circadian rhythm in photosynthesis was due to reduced lea: internal CO2 concentrations during the subjective night, as a result of rhythmic stomatal closure Chilling-induced interference with circadian timing in mango, does not play the central role in chilling inhibition of photosynthesis that has previously been demonstrated in certain chilling sensitive herbaceous plants. Practical implications of the research achievements are feasible, but require few more years of research.
2
Steffens, John C., and Eithan Harel. Polyphenol Oxidases- Expression, Assembly and Function. United States Department of Agriculture, 1995. http://dx.doi.org/10.32747/1995.7571358.bard.
Full textAbstract:
Polyphenol oxidases (PPOs) participate in the preparation of many plant products on the one hand and cause considerable losses during processing of plant products on the other hand. However, the physiological functions of plant PPO were still a subject of controversy at the onset of the project. Preliminary observations that suggested involvement of PPOs in resistance to herbivores and pathogens held great promise for application in agriculture but required elucidation of PPO's function if modulation of PPO expression is to be considered for improving plant protection or storage and processing of plant products. Suggestions on a possible role of PPO in various aspects of chloroplast metabolism were also relevant in this context. The characterization of plant PPO genes opened a way for achieving these goals. We reasoned that "understanding PPO targeting and routing, designing ways to manipulate its expression and assessing the effects of such modifications will enable determination of the true properties of the enzyme and open the way for controlling its activity". The objective of the project was to "obtain an insight into the function and biological significance of PPOs" by examining possible function(s) of PPO in photosynthesis and plant-pest interactions using transgenic tomato plants; extending our understanding of PPO routing and assembly and the mechanism of its thylakoid translocation; preparing recombinant PPOs for use in import studies, determination of the genuine properties of PPOs and understanding its assembly and determining the effect of PPO's absence on chloroplast performance. Results obtained during work on the project made it necessary to abandon some minor objectives and devote the effort to more promising topics. Such changes are mentioned in the 'Body of the report' which is arranged according to the objectives of the original proposal. The complex expression pattern of tomato PPO gene family was determined. Individual members of the family are differentially expressed in various parts of the plant and subjected to developmentally regulated turnover. Some members are differentially regulated also by pathogens, wounding and chemical wound signals. Wounding systemically induces PPO activity and level in potato. Only tissues that are developmentally competent to express PPO are capable of responding to the systemic wounding signal by increased accumulation of PPO mRNA. Down regulation of PPO genes causes hyper susceptibility to leaf pathogens in tomato while over expression regulation of PPO expression in tomato plants is their apparent increased tolerance to drought. Both the enhanced disease resistance conferred by PPO over expression and the increased stress tolerance due to down regulation can be used in the engineering of improved crop plants. Photosynthesis rate and variable fluorescence measurements in wild type, and PPO-null and over expressing transgenic tomato lines suggest that PPO does not enable plants to cope better with stressful high light intensities or reactive oxygen species. Rather high levels of the enzyme aggravate the damage caused under such conditions. Our work suggests that PPO's primary role is in defending plants against pathogens and herbivores. Jasmonate and ethylene, and apparently also salicylate, signals involved in responses to wounding and defense against herbivores and pathogens, enhance markedly and specifically the competence of chloroplasts to import and process pPPO. The interaction of the precursor with thylakoid membranes is primarily affected. The routing of PPO shows other unusual properties: stromal processing occurs in two sites, resulting in intermediates that are translocated across thylakoids by two different mechanisms - a DpH- and a Sec-dependent one. It is suggested that the dual pattern of processing and routing constitutes a'fail safe' mechanism, reflecting the need for a rapid and flexible response to defense challenges. Many of the observations described above should be taken into consideration when manipulation of PPO expression is contemplated for use in crop improvement.
3
Shani, Uri, Lynn Dudley, Alon Ben-Gal, Menachem Moshelion, and Yajun Wu. Root Conductance, Root-soil Interface Water Potential, Water and Ion Channel Function, and Tissue Expression Profile as Affected by Environmental Conditions. United States Department of Agriculture, 2007. http://dx.doi.org/10.32747/2007.7592119.bard.
Full textAbstract:
Constraints on water resources and the environment necessitate more efficient use of water. The key to efficient management is an understanding of the physical and physiological processes occurring in the soil-root hydraulic continuum.While both soil and plant leaf water potentials are well understood, modeled and measured, the root-soil interface where actual uptake processes occur has not been sufficiently studied. The water potential at the root-soil interface (yᵣₒₒₜ), determined by environmental conditions and by soil and plant hydraulic properties, serves as a boundary value in soil and plant uptake equations. In this work, we propose to 1) refine and implement a method for measuring yᵣₒₒₜ; 2) measure yᵣₒₒₜ, water uptake and root hydraulic conductivity for wild type tomato and Arabidopsis under varied q, K⁺, Na⁺ and Cl⁻ levels in the root zone; 3) verify the role of MIPs and ion channels response to q, K⁺ and Na⁺ levels in Arabidopsis and tomato; 4) study the relationships between yᵣₒₒₜ and root hydraulic conductivity for various crops representing important botanical and agricultural species, under conditions of varying soil types, water contents and salinity; and 5) integrate the above to water uptake term(s) to be implemented in models. We have made significant progress toward establishing the efficacy of the emittensiometer and on the molecular biology studies. We have added an additional method for measuring ψᵣₒₒₜ. High-frequency water application through the water source while the plant emerges and becomes established encourages roots to develop towards and into the water source itself. The yᵣₒₒₜ and yₛₒᵢₗ values reflected wetting and drying processes in the rhizosphere and in the bulk soil. Thus, yᵣₒₒₜ can be manipulated by changing irrigation level and frequency. An important and surprising finding resulting from the current research is the obtained yᵣₒₒₜ value. The yᵣₒₒₜ measured using the three different methods: emittensiometer, micro-tensiometer and MRI imaging in both sunflower, tomato and corn plants fell in the same range and were higher by one to three orders of magnitude from the values of -600 to -15,000 cm suggested in the literature. We have added additional information on the regulation of aquaporins and transporters at the transcript and protein levels, particularly under stress. Our preliminary results show that overexpression of one aquaporin gene in tomato dramatically increases its transpiration level (unpublished results). Based on this information, we started screening mutants for other aquaporin genes. During the feasibility testing year, we identified homozygous mutants for eight aquaporin genes, including six mutants for five of the PIP2 genes. Including the homozygous mutants directly available at the ABRC seed stock center, we now have mutants for 11 of the 19 aquaporin genes of interest. Currently, we are screening mutants for other aquaporin genes and ion transporter genes. Understanding plant water uptake under stress is essential for the further advancement of molecular plant stress tolerance work as well as for efficient use of water in agriculture. Virtually all of Israel’s agriculture and about 40% of US agriculture is made possible by irrigation. Both countries face increasing risk of water shortages as urban requirements grow. Both countries will have to find methods of protecting the soil resource while conserving water resources—goals that appear to be in direct conflict. The climate-plant-soil-water system is nonlinear with many feedback mechanisms. Conceptual plant uptake and growth models and mechanism-based computer-simulation models will be valuable tools in developing irrigation regimes and methods that maximize the efficiency of agricultural water. This proposal will contribute to the development of these models by providing critical information on water extraction by the plant that will result in improved predictions of both water requirements and crop yields. Plant water use and plant response to environmental conditions cannot possibly be understood by using the tools and language of a single scientific discipline. This proposal links the disciplines of soil physics and soil physical chemistry with plant physiology and molecular biology in order to correctly treat and understand the soil-plant interface in terms of integrated comprehension. Results from the project will contribute to a mechanistic understanding of the SPAC and will inspire continued multidisciplinary research.