Cell injury, adaptation and death mit opencourseware. There may also be a switch of contractile proteins from adult to fetal or neonatal forms. Difference between reversible and irreversible cell injury. Cell injury general mechanisms four very interrelated cell systems are. Identify the three major mechanisms of cell injury and. Jun 11, 2015 this topic covers the mechanism of irreversible cell injury. To define and describe in general terms physiological adaptations, reversible and irreversible injury and cell death. Cell response to injury is not an allornothing phenomenon. Cell injury, cell death, and adaptations examples of cell injury and necrosis ischemic and hypoxic injury ischemiareperfusion injury chemical toxic injury apoptosis causes of apoptosis mechanisms of apoptosis examples of apoptosis intracellular accumulations pathologic calci. Chapter 1 cellular adaptations, cell injury, and cell death 5 if the limits of adaptive response to a stimulus are exceeded, or in certain instances when the cell is exposed to an injurious agent or stress, a sequence of events follows that is loosely termed cell injury.
Cell shrinkage, apoptotic bodies which are eaten by macrophages. Extremely important common cause of cell injury cell death. Discriminate cell adaptation, reversible cell injury and irreversible cell injury cell death based on etiology, pathogenesis and histological and ultrastructural appearance. Start studying pathology lecture 3 mechanisms of cell injury and necrosis. Over the next 2 months, the lymphoma decreases in size, as documented on abdominal ct scans. Stem cell quiescence is a dormant but reversible cellular state in which cellcycle entry and proliferation are prevented. Therapeutic modulation of stem cell quiescence could restore tissue homeostasis. Loss of ca homeostasis, often in the form of cytoplasmic increases, leads to cell injury. Chemical injury induce cell injury by one of two general mechanisms. Likewise, cell death also has value for the species, as it provides a mechanism for eliminating terminally injured. Vascular endothelial cells normally perform several key homeostatic functions such as keeping blood fluid, regulating blood flow, regulating macromolecule and fluid exchange with the tissues, preventing leukocyte activation, and aiding in immune surveillance for pathogens. Cell death mechanisms and modulation in traumatic brain injury bogdan a.
Sutton1 1 division of surgery and oncology and 2 department of physiology, university of liverpool, liverpool l69 3bx, uk abstract acute pancreatitis has many causes, all leading to a common pathway of changes. Terms in this set 29 what is the most common immediate cause of cell injury and what are the mechanisms. Identify the three major mechanisms of cell injury and their. Extremely important common cause of cell injurycell death. Mechanisms of carrageenan injury of iec18 small intestinal. Sep 22, 2009 cell injury may be reversible or irreversible 6. In the past, most research has concentrated on the mechanisms causing cellular injury during ischemia and on protective procedures designed to reduce development of ischemic injury. Cell injury results from different chemical mechanisms that act on several cellular componentsamong these are depletion of atp mitochondrial damage influx of calcium and loss of calcium homeostasis accumulation of oxygenderived free radicals oxidative stress defects in membrane permeability cell injury results from different. Pdf liver cell death is triggered by a number of insults arising from the external environment or from within the cell.
Therefore, although an injurious agent may target a particular aspect of cell structure or function, this will rapidly lead to wideranging secondary effects. Cell injury results from different chemical mechanisms that act on several cellular componentsamong these are depletion of atp mitochondrial damage influx of calcium and loss of calcium homeostasis accumulation of oxygenderived free radicals oxidative stress defects in membrane permeability cell injury results from different chemical mechanisms that act on several cellular components. Faden shock, trauma and anesthesiology research star center, national study center for trauma and ems, university of maryland, school of medicine, baltimore, maryland 21201 summary. Both types of cell death mechanisms are able to trigger fibrosis through stimulation.
When cell death occurs in the living body, the term necrosis is used. Mechanisms of cell injury and death in hyperoxia role of. Irreversible cell injury can be recognized by changes in the appearance of the nucleus and rupture of the cell membrane. This topic covers the mechanism of irreversible cell injury. Mechanical trauma, extremes of temperature burns and deep cold, sudden changes in atmospheric pressure, radiation, and electric. Mechanisms of cell injury in the killing of cultured hepatocytes by bromobenzene. At the cellular level, there are many processes that can lead to necrosis. Characteristics and mechanisms of cell injury and cell death. Mechanisms of carrageenan injury of iec18 small intestinal epithelial cell monolayers kityin ling, deepak bhalla, and daniel hollander division of gastroenterology, department of medicine and department of community and environmental medicine, university of california at irvine, irvine, california.
In addition to blunt and sharp mechanisms, there is the situation of thermal energy in the form of heat, cold, or chemical agent, which generates the heat or. Adaptation and reversible injury patterns of tissue. Restraints worn properly lap and shoulder hold the occupant in place with minimal movement as well as minimal injury. Nov 26, 20 various mechanisms of cell injury how atp depletion causes cell injury will make and upload part 2 about irreversible cell injury within a week hopefully. Lots of it changes on a daily basis so today will be a broad overview. Adaptation and reversible injury patterns of tissue necrosis. Mechanisms of neutrophilinduced liver cell injury during hepatic ischemiareperfusion and other acute in. Mechanisms of cell injury free download as powerpoint presentation. Apoptosis and senescence are the main causes of fibrosis following exposure to high doses of ionizing radiation. Cell death mechanisms and modulation in traumatic brain injury. Causes include reduced blood flow ischemia, inadequate oxygenation of the blood, decreased blood oxygencarrying capacity. Mechanisms of cell injury by activated oxygen species. Chapter 1 mechanisms of injury introduction trauma starts with the transfer of energy to the body from an outside force.
Mechanical trauma, extremes of temperature burns and deep cold, sudden changes in atmospheric pressure, radiation, and electric shock. General principles cell response to injury is not an allornothing phenomenon response to a given stimulus depends on the type, status, and genetic makeup of the injured cell cells are complex interconnected systems, and single local injuries can result in multiple secondary and tertiary effects cell function is lost far before biochemical and. Although multiple destructive processes are activated by ca, lethal outcomes are determined largely by cainduced mitochondrial permeability transition. If the adaptive capability is exceeded or if the external stress is inherently harmful, cell injury develops fig. Mechanisms of cell injury and death 5 figure 1 electron micrographs of murine thymocytes from normal a, sham laparotomy and septic b, caecal ligation and puncture mice. Learn vocabulary, terms, and more with flashcards, games, and other study tools. Cell death apply knowledge of biochemistry and cellular physiology to differentiate between pathogenic and physiologic mechanisms of cell death, the resulting morphologic appearance and the physiologic and. Intrinsic regulators include the cell cycle machinery, autophagy, chromatin modifiers, and micrornas. Strayer emanuel rubin p athology is basically the study of structural and functional abnormalities that are expressed as diseases of organs and systems. Depending upon cell type and the intensity of ca toxicity, the ensuing pathology can be reversible or irreversible. Cell injury it is change in cells morphology and function in response to stress. The mechanisms underlying the processes described above involve. British journal of anaesthesia, volume 77, issue 1, 1 july 1996, pag.
By which of the following mechanisms has her neoplasm primarily responded to therapy. The major characteristics of cell injury are atp depletion loss of mitochondrial atp and decreased atp synthesis which results in cellular swelling, decreased protein synthesis, decreased membrane transport. The cellular basis of disease cell injury 2 mechanisms of cell injury christine hulette md details from today are continually revised and updated with research. Cell injury it is change in cell s morphology and function in response to stress. The airbag has room to deploy at approximately 200 mph without severe injury to the occupant. This is the key difference between reversible and irreversible cell injury. Stem cell quiescence is a dormant but reversible cellular state in which cell cycle entry and proliferation are prevented. At present, a logical strategy for manipulating no production in the treatment of liver disease has not emerged. Discuss the importance of injury prevention as part of the continuum of trauma care. Neuronal injury in bacterial meningitis is not a monocausal event. Evidence for the participation of activated oxygen species and the resulting peroxidation of lipids in. Mechanisms of cell injury the structure and metabolic functions of the cell are interdependent. The cellular organelles that play major role in these processes are mitochondria and lysosomes.
Extrinsic regulators include celladhesion molecules and secreted factors. Several mechanisms of damage activate mediators, ultimately, leading to. Injury or cell death impairs or prevents conduct of these activities, resulting in dysfunction. Evidence for the participation of activated oxygen species and the resulting peroxidation of lipids in the killing of cultured hepatocytes by aryl halides. Some chemicals act directly by combining with a critical molecular component or cellular organelle. Identify the three major mechanisms of cell injury and their distinguishing characteristics. Control of the rate of cell death relative to the rate of cell division maintains organ integrity and physiological homeostasis. Neuronal and glial cell death and traumatic axonal injury contribute to the overall pathology of traumatic brain injury tbi in both humans and animals. When cells are injured, one of two patterns will generally result. Summarize the cell s response to reperfusion injury emphasizing how reperfusion can exacerbate injury produced by ischemia. Reversible cell injury results in morphological and cellular changes that could be reversed if the stress is taken off.
Mechanisms of endothelial dysfunction, injury, and death. Summarize the cells response to reperfusion injury emphasizing how reperfusion can exacerbate injury produced by ischemia. Cell death is valuable for the organism because it removes terminally injured or unwanted cells that utilize valuable substrates and nutrients. This chapter will present an overview of how the pathologist views mechanisms of irreversible cell injury cell death, reversible cell injury, and the organisms response to both. General mechanism of cell injury flashcards quizlet.
Extrinsic regulators include cell adhesion molecules and secreted factors. Introduction cell injury is defined as a variety of stresses a cell encounters as a result of changes in its internal and external environment. Cellular function is lost far before cell death occurs, and the morphologic changes of. Over the past decade, the nomenclature committee on cell death nccd has formulated guidelines for the definition and interpretation of cell death. Injury mechanisms in acute intracerebral hemorrhage. She is treated with a chemotherapeutic agent which results in the loss of individual neoplastic cells through fragmentation of individual cell nuclei and cytoplasm.
Department of pathology, university of maryland, school. The free radical theory stating that lung cells poison themselves by producing an endogenous excess of reactive oxygen species ros within. General mechanism of cell injury learn with flashcards, games, and more for free. In this video we have discussed the different mechanisms of cell injury. Pathology lecture 3 mechanisms of cell injury and necrosis. Cell injury occurs when the limits to an adaptive response adaptation have been exceeded or if the cells are not able to adapt. Causes of cell injury the causes of cell injury range from the external gross physical violence of an automobile accident to subtle internal abnormalities, such as a genetic mutation causing lack of a vital enzyme that impairs normal metabolic function. General principles cell response to injury is not an allornothing phenomenon response to a given stimulus depends on the type, status, and genetic makeup of the injured cell cells are complex interconnected systems, and single local injuries can result in multiple secondary and tertiary effects.
Pdf mechanisms of cell injury and death researchgate. Mechanisms, hallmarks, and implications of stem cell. Cellular function is lost far before cell death occurs, and the morphologic changes of cell injury or death lag far behind both. Chu, md, phd associate professor of pathology university of pittsburgh school of medicine summer academy 2010. In most cases, the process can be classified as one or other of two main mechanisms. Mechanism of irreversible cell injury the art of medicine. Classic theories of disease attributed disease to imbalances or noxious effects of humors on specific organs. Over the past decade, the nomenclature committee on cell death nccd has formulated guidelines for the definition and interpretation of cell death from morphological, biochemical, and functional. It is change in cells morphology and function in response to. Pdf mechanisms of cell death in hypoxiareoxygenation injury. Pdf on aug 1, 1996, j p cobb and others published mechanisms of cell injury and death find, read and cite all the research you need on. Mechanisms of liver cell injury cell death and liver disease the role of apoptosis in clinical liver disease has been recognized mainly on the basis of histopathology. Identify patterns of injury from the type of mechanism deployed to the patient. For example, in mercuric chloride poisoning from ingestion of contaminated seafood, mercury binds to the sulfhydryl groups of various cell membrane.
Cell death mechanisms following traumatic brain injury. Scribd is the worlds largest social reading and publishing site. Define and understand the morphologic patterns of lethal cell injury and the clinical settings in which they occur. Cell injury, cell death, and adaptations new age medical. Irreversible cell injury results in complete cell death and normal cellular conditions cannot be achieved even if the stress is relieved. The transfer of kinetic energy may be blunt or sharp in nature. Intrinsic regulators include the cellcycle machinery, autophagy, chromatin modifiers, and micrornas. Describe the importance of the mechanism of injury in history taking of the trauma patient. May 15, 2018 despite an increase in research and trials of therapies for ich, mortality remains high and no interventional therapy has been demonstrated to improve outcomes. Although much knowledge exists on the mechanisms of injury and regeneration, reliable treatments that ensure full functional recovery are scarce. The major characteristics of cell injury are atp depletion loss of mitochondrial atp and decreased atp synthesis which results in cellular swelling, decreased protein synthesis, decreased membrane transport and lipogenesis. Within certain limits injury is reversible, and cells return to a stable baseline. May 15, 2018 in this video we have discussed the different mechanisms of cell injury. Hypoxia is the most important cause of cell injury.
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