This document discusses the body's response to injurious agents and cellular adaptations. It begins by explaining the body's natural defense mechanisms against bacteria, viruses, and trauma. These include physical barriers, detoxification, immune response, and cellular response. When defenses are inadequate, inflammation may develop. The document then covers different types of cellular adaptations like atrophy, hypertrophy, hyperplasia, and metaplasia. It also discusses reversible vs irreversible cell injury and various causes of cell injury including hypoxia, physical agents, chemicals, infections, and more.
This document provides an introduction to the field of pathology. It defines pathology as the study of disease through scientific methods and discusses how pathology examines the structural, biochemical, and functional changes that underlie disease. The document outlines several key topics in pathology including the core aspects of disease, diagnostic techniques, categories of disease causes, and the course and consequences of diseases. It also provides a brief history of the field and discusses pioneers like Rudolf Virchow. Various cellular responses to injury like adaptation, injury, and death are examined in detail.
This document discusses mechanical injuries, including abrasions, contusions, lacerations, and other types of wounds. It provides details on the characteristics and features of each type of injury, as well as factors that influence the nature and extent of wounds. Mechanical injuries are caused by physical forces that result in tissue damage. The summary examines the key types of mechanical injuries and their forensic significance in determining cause and manner of injuries.
This document discusses factors that determine the appearance of mechanical injuries, including the type of weapon, how force is applied, the tissue properties, and movement. Weapon shape directly influences wound shape. Direct force causes impact injuries at the site, while indirect force causes injuries away from the impact. Tissue resistance and architecture also impact wound appearance. Proper analysis of these factors can provide clues about the causative agent.
This document outlines objectives and content for a lecture on cell injury. The key points are:
1. Students should understand concepts of cellular adaptation to stress through hypertrophy, hyperplasia, atrophy, and metaplasia.
2. Hypoxic cell injury is a major cause of cell damage and can result from ischemia, anemia, or poor oxygenation.
3. Apoptosis and necrosis are the two main types of cell death, with necrosis occurring due to ischemia or chemicals and apoptosis through programmed suicide.
4. Causes of reversible and irreversible cell injury include hypoxia, physical agents, chemicals, infections, and genetic or nutritional factors.
This document discusses the biological effects of radiation exposure on humans. It describes how radiation interacts with atoms and can cause damage at the cellular level by direct interaction with DNA or indirect interaction through radiolytic decomposition of water within cells. Different cell types and organs vary in their sensitivity to radiation depending on factors like rate of cell reproduction. High doses of radiation can cause acute effects like radiation sickness, while low chronic doses may increase long-term cancer risk. A summary of average annual radiation exposure for a US citizen is also provided.
This document provides an introduction to histopathology. It discusses that histopathology is the branch of pathology that deals with tissue changes associated with disease, using microscopic examination of biopsy specimens. It also provides background on pathology, noting that pathology involves the study of structural and functional changes in tissues that cause disease. Several pioneers in the fields of anatomy, microscopy, and cellular pathology are discussed, including Hippocrates, Aristotle, Van Leeuwenhoek, Morgagni, Bichat, and Virchow. Basic terminology used in pathology is defined.
This document discusses different types of cell damage and death. It describes reversible cell injury/degeneration caused by mild to moderate stress that allows cells to recover, and irreversible cell injury/necrosis from persistent severe stress leading to cell death. Various types of cell death are also defined, including programmed cell death pathways of apoptosis, autophagy and necrosis. Specific patterns of necrosis - coagulative, liquefactive, caseous and others - are then outlined based on their causes and characteristic gross appearances.
1. Trauma can be caused by mechanical, thermal, electric, radiation, psychological or other external agents and results in anatomical and functional damage to organs and tissues. Trauma can be classified as industrial, non-industrial, intentional, or by the type of damaging agent.
2. Closed soft tissue injuries include contusions, strains, ruptures, concussions and crushes. Contusions occur without skin breaks and cause pain, swelling and loss of function. Strains and ruptures are caused by excessive stretching forces and can damage ligaments, fascia, muscles and tendons.
3. Fractures break the normal continuity of bone while dislocations are complete disruptions of joints with abnormal contact
This document provides an introduction to the field of pathology. It defines pathology as the study of disease through scientific methods and discusses how pathology examines the structural, biochemical, and functional changes that underlie disease. The document outlines several key topics in pathology including the core aspects of disease, diagnostic techniques, categories of disease causes, and the course and consequences of diseases. It also provides a brief history of the field and discusses pioneers like Rudolf Virchow. Various cellular responses to injury like adaptation, injury, and death are examined in detail.
This document discusses mechanical injuries, including abrasions, contusions, lacerations, and other types of wounds. It provides details on the characteristics and features of each type of injury, as well as factors that influence the nature and extent of wounds. Mechanical injuries are caused by physical forces that result in tissue damage. The summary examines the key types of mechanical injuries and their forensic significance in determining cause and manner of injuries.
This document discusses factors that determine the appearance of mechanical injuries, including the type of weapon, how force is applied, the tissue properties, and movement. Weapon shape directly influences wound shape. Direct force causes impact injuries at the site, while indirect force causes injuries away from the impact. Tissue resistance and architecture also impact wound appearance. Proper analysis of these factors can provide clues about the causative agent.
This document outlines objectives and content for a lecture on cell injury. The key points are:
1. Students should understand concepts of cellular adaptation to stress through hypertrophy, hyperplasia, atrophy, and metaplasia.
2. Hypoxic cell injury is a major cause of cell damage and can result from ischemia, anemia, or poor oxygenation.
3. Apoptosis and necrosis are the two main types of cell death, with necrosis occurring due to ischemia or chemicals and apoptosis through programmed suicide.
4. Causes of reversible and irreversible cell injury include hypoxia, physical agents, chemicals, infections, and genetic or nutritional factors.
This document discusses the biological effects of radiation exposure on humans. It describes how radiation interacts with atoms and can cause damage at the cellular level by direct interaction with DNA or indirect interaction through radiolytic decomposition of water within cells. Different cell types and organs vary in their sensitivity to radiation depending on factors like rate of cell reproduction. High doses of radiation can cause acute effects like radiation sickness, while low chronic doses may increase long-term cancer risk. A summary of average annual radiation exposure for a US citizen is also provided.
This document provides an introduction to histopathology. It discusses that histopathology is the branch of pathology that deals with tissue changes associated with disease, using microscopic examination of biopsy specimens. It also provides background on pathology, noting that pathology involves the study of structural and functional changes in tissues that cause disease. Several pioneers in the fields of anatomy, microscopy, and cellular pathology are discussed, including Hippocrates, Aristotle, Van Leeuwenhoek, Morgagni, Bichat, and Virchow. Basic terminology used in pathology is defined.
This document discusses different types of cell damage and death. It describes reversible cell injury/degeneration caused by mild to moderate stress that allows cells to recover, and irreversible cell injury/necrosis from persistent severe stress leading to cell death. Various types of cell death are also defined, including programmed cell death pathways of apoptosis, autophagy and necrosis. Specific patterns of necrosis - coagulative, liquefactive, caseous and others - are then outlined based on their causes and characteristic gross appearances.
1. Trauma can be caused by mechanical, thermal, electric, radiation, psychological or other external agents and results in anatomical and functional damage to organs and tissues. Trauma can be classified as industrial, non-industrial, intentional, or by the type of damaging agent.
2. Closed soft tissue injuries include contusions, strains, ruptures, concussions and crushes. Contusions occur without skin breaks and cause pain, swelling and loss of function. Strains and ruptures are caused by excessive stretching forces and can damage ligaments, fascia, muscles and tendons.
3. Fractures break the normal continuity of bone while dislocations are complete disruptions of joints with abnormal contact
This document provides an overview of pathology and inflammation. It defines pathology as the scientific study of disease, and notes that the goal of pathology is to identify the causes of disease to enable treatment and prevention. The document then discusses the history of pathology and definitions of disease, characteristics of disease such as etiology and pathogenesis. It also covers topics like cellular adaptations to growth and differentiation, types of cell injury, apoptosis, necrosis, and cell renewal in adults. Finally, it introduces the topic of inflammation as a protective response to eliminate the cause of injury and damaged cells/tissues.
This document provides an overview of pathology and disease. It defines pathology as the scientific study of disease, noting it examines functional and structural changes from the molecular to individual level. The goal of pathology is identifying disease causes to enable treatment and prevention. The document discusses the history of pathology and autopsy examinations. It defines disease as an abnormality causing ill health and outlines disease characteristics like aetiology, pathogenesis, structural and functional manifestations, and prognosis. It also covers topics like growth, differentiation, morphogenesis, and cellular adaptations to stimuli like hyperplasia and hypertrophy.
This document provides an overview of fractures, including definitions, related terms, causes, clinical features, classifications, and the healing process. It defines a fracture as a break or disruption in bone continuity. Fractures are classified based on etiology, soft tissue involvement, displacement, fracture pattern, and number of bone fragments. The healing process involves hematoma formation, granulation tissue growth, callus formation, ossification, consolidation, and remodeling over several months.
fracture introduction, aetiology, complete and incomplete fractures, traumatic and pathologic fractures, simple and compound fractures, patterns of fractures and types of displacement
Pathology of the musculoskeletal system 2016Chapima Fabian
This document provides an overview of bone pathology and various bone diseases. It begins with an introduction to the mechanical, mineral storage and hematopoietic functions of bones. The rest of the document is outlined and covers various congenital bone diseases like achondroplasia and osteogenesis imperfecta, acquired bone diseases including fractures, osteonecrosis, osteomyelitis and tuberculosis of bone. For each disease, it discusses pathogenesis, clinical features, signs and symptoms as well as treatment where relevant.
Wound Management Presentation by Rebira.pptxRebiraWorkineh
This document outlines a presentation on wound management given by Rebira W., a student in the Adult Health Nursing postgraduate program. The objectives of the presentation are to describe the structures and functions of skin, understand the impact of wounds on quality of life, identify different types of wounds and factors affecting wound healing, and know how to manage both acute and chronic wounds. The presentation covers topics such as the anatomy of skin and its layers, types of wounds classified by origin, the phases of wound healing, and managing specific wound types like pressure sores and diabetic foot ulcers.
1. The document discusses tissue engineered allograft implants and regenerative medicine, focusing on the skin as the largest organ. It describes the layers and functions of skin, as well as how the body responds to burns through inflammation and regeneration.
2. When the body is damaged by burns, it initiates an inflammatory response by increasing blood flow and sending white blood cells to the injured area. If damage is superficial, the skin can regenerate itself through restitution, but deeper burns result in scarring as the body replaces damaged tissue with collagen fibers.
3. Burn injuries are a serious threat, with common causes being fires, scalds from hot liquids, and contact with hot surfaces. Household items like st
What is a pressure ulcer?
Define the PU
Know how much the economical burden for PU
This Presentation we will answer one main question
Why does pressure ulcers happen?
Cells maintain homeostasis but can be stressed by external factors. Adaptive responses include hypertrophy, hyperplasia, atrophy and metaplasia, but severe stress leads to injury and cell death via necrosis or apoptosis. Necrosis involves loss of membrane integrity while apoptosis is genetically programmed cell suicide. Various stresses can cause reversible or irreversible injury through mechanisms like ATP depletion, calcium dysregulation, and damage to organelles and DNA.
Cell injury occurs when homeostasis is disturbed and the limits of adaptive responses are exceeded. There are two main types of cell injury: reversible and irreversible. Reversible injury involves functional and morphological changes that can be reversed if the damaging stimulus is removed, such as reduced ATP and cellular swelling. Irreversible injury cannot be recovered from and leads to cell death, either through necrosis or apoptosis. Common causes of cell injury include oxygen deprivation, physical agents, chemical agents, infectious agents, immunological reactions, genetic defects, and nutritional imbalances. The initial manifestation of most injuries is cellular swelling. Mechanisms of injury involve ATP depletion, mitochondrial damage, calcium influx, reactive oxygen species accumulation, and increased membrane permeability, typically culminating in necrosis or
11. INFLAMMATION DENTISTRY IN SIMPLER TERMS.pptSamkeloKhumalo2
What Is Inflammation?
Inflammation is a process by which your body's white blood cells and the things they make protect you from infection from outside invaders, such as bacteria and viruses.
But in some diseases, like arthritis, your body's defense system -- your immune system -- triggers inflammation when there are no invaders to fight off. In these autoimmune diseases, your immune system acts as if regular tissues are infected or somehow unusual, causing damage.
Pathology is the study of disease through examination of cells, tissues, and organs. The key aspects studied in pathology include the etiology (cause), pathogenesis (mechanism by which the cause produces changes), morphologic changes (structural changes visible microscopically), clinical manifestations (symptoms and signs), prognosis, and complications of diseases. Cellular responses to injury can include adaptations like hypertrophy, hyperplasia, atrophy, and metaplasia, or cell injury/death through necrosis and apoptosis. Necrosis is cell death caused by external factors and is always pathological. Pathology is important for medical education, diagnosis, treatment, and prevention of disease.
Cellular adaptations and injury can occur through various mechanisms:
(1) When cells are exposed to stressors, they may undergo reversible changes like atrophy, hypertrophy, hyperplasia, metaplasia, or dysplasia to adapt. (2) If the stressors are severe or persistent, irreversible cell injury and death through necrosis or apoptosis can result. (3) Cellular injury can be caused by free radicals, hypoxia, physical trauma, chemicals, radiation, or biological agents and can lead to tissue dysfunction or infection if necrosis occurs.
Fracture types - Plaster Of Paris tecniques and ComplicationsVenkatesh Ghantasala
This document discusses fracture types, classifications, and POP techniques and complications. It begins by explaining the purposes of fracture classification systems which include characterizing fractures, guiding treatment, predicting outcomes, and having a common language. It then discusses the history of classifications and different classification systems including fracture-specific, generic, and those based on soft tissue injury. The rest of the document details different fracture types such as based on mechanism, soft tissue involvement, displacement, pattern, fragments, and pediatric fractures. It also provides examples of fracture classifications and eponyms.
This document provides an overview of pathology and the causes and types of cell injury and death. It defines pathology as the study of disease, including the underlying causes (etiology), mechanisms of development (pathogenesis), structural changes in cells and organs (morphology), and functional consequences (clinical significance). The main types of cell injury discussed are reversible injury, where function and structure can return to normal if the stimulus is removed, and necrosis, which is accidental cell death where membranes break down and enzymes digest the cell, causing inflammation. Apoptosis is also mentioned as a programmed form of cell death. Causes of cell injury include genetic defects, hypoxia, toxins, infections, immune reactions, nutritional imbalances, physical agents, and
1. This document provides definitions and clinical features of fractures of the long bones and upper limbs. It discusses the different types of fractures that can occur in these areas, including open vs closed fractures.
2. The clinical presentation of acute fractures typically includes pain, swelling, loss of function, and possible deformity or crepitus. Malunited fractures may cause limitations in range of motion or impingement.
3. The causes of fractures depend on the mechanism of injury, such as a direct blow, twist, or angulation, and can result in different fracture patterns visible on x-rays. High velocity injuries commonly cause comminuted fractures.
Innate and adaptive immunity, B LYMPHOCYTES, T LYMPHOCYTES, ANTIGEN-PRESENTING CELLS, Humoral Immunity But Not Cellular Immunity Is Transferred with Antibody, Exogenous PATHWAY, Endogenous pathway, Differences in the primary and secondary response, Immune Dysfunction and Its Consequences, Immune Response to Infectious Diseases, Viral Infections, Bacterial Infections
1) The document discusses biological responses to materials, including fundamental tissue responses like injury, inflammation, and foreign body reaction, as well as in vivo evaluation of these responses.
2) It first describes the tissue response continuum that occurs after implantation, including injury, blood-material interactions, provisional matrix formation, acute inflammation, and fibrosis or fibrous capsule development.
3) The document then discusses in vivo evaluation of tissue responses to materials, which is necessary to determine biocompatibility and predict potential harm to patients.
A fracture is a break in a bone caused by physical force exceeding the bone's strength. There are different types of fractures including simple/closed fractures where the skin is intact, compound/open fractures where the skin is broken, and transverse fractures which occur at right angles to the bone. Symptoms include pain, swelling, bruising, inability to move or bear weight on the injured area. Fractures are typically diagnosed through physical exam and imaging tests like x-rays. Treatment involves immobilizing the area with splints, casts, traction, or surgery depending on the fracture type to promote healing.
This document provides an overview of pathology and inflammation. It defines pathology as the scientific study of disease, and notes that the goal of pathology is to identify the causes of disease to enable treatment and prevention. The document then discusses the history of pathology and definitions of disease, characteristics of disease such as etiology and pathogenesis. It also covers topics like cellular adaptations to growth and differentiation, types of cell injury, apoptosis, necrosis, and cell renewal in adults. Finally, it introduces the topic of inflammation as a protective response to eliminate the cause of injury and damaged cells/tissues.
This document provides an overview of pathology and disease. It defines pathology as the scientific study of disease, noting it examines functional and structural changes from the molecular to individual level. The goal of pathology is identifying disease causes to enable treatment and prevention. The document discusses the history of pathology and autopsy examinations. It defines disease as an abnormality causing ill health and outlines disease characteristics like aetiology, pathogenesis, structural and functional manifestations, and prognosis. It also covers topics like growth, differentiation, morphogenesis, and cellular adaptations to stimuli like hyperplasia and hypertrophy.
This document provides an overview of fractures, including definitions, related terms, causes, clinical features, classifications, and the healing process. It defines a fracture as a break or disruption in bone continuity. Fractures are classified based on etiology, soft tissue involvement, displacement, fracture pattern, and number of bone fragments. The healing process involves hematoma formation, granulation tissue growth, callus formation, ossification, consolidation, and remodeling over several months.
fracture introduction, aetiology, complete and incomplete fractures, traumatic and pathologic fractures, simple and compound fractures, patterns of fractures and types of displacement
Pathology of the musculoskeletal system 2016Chapima Fabian
This document provides an overview of bone pathology and various bone diseases. It begins with an introduction to the mechanical, mineral storage and hematopoietic functions of bones. The rest of the document is outlined and covers various congenital bone diseases like achondroplasia and osteogenesis imperfecta, acquired bone diseases including fractures, osteonecrosis, osteomyelitis and tuberculosis of bone. For each disease, it discusses pathogenesis, clinical features, signs and symptoms as well as treatment where relevant.
Wound Management Presentation by Rebira.pptxRebiraWorkineh
This document outlines a presentation on wound management given by Rebira W., a student in the Adult Health Nursing postgraduate program. The objectives of the presentation are to describe the structures and functions of skin, understand the impact of wounds on quality of life, identify different types of wounds and factors affecting wound healing, and know how to manage both acute and chronic wounds. The presentation covers topics such as the anatomy of skin and its layers, types of wounds classified by origin, the phases of wound healing, and managing specific wound types like pressure sores and diabetic foot ulcers.
1. The document discusses tissue engineered allograft implants and regenerative medicine, focusing on the skin as the largest organ. It describes the layers and functions of skin, as well as how the body responds to burns through inflammation and regeneration.
2. When the body is damaged by burns, it initiates an inflammatory response by increasing blood flow and sending white blood cells to the injured area. If damage is superficial, the skin can regenerate itself through restitution, but deeper burns result in scarring as the body replaces damaged tissue with collagen fibers.
3. Burn injuries are a serious threat, with common causes being fires, scalds from hot liquids, and contact with hot surfaces. Household items like st
What is a pressure ulcer?
Define the PU
Know how much the economical burden for PU
This Presentation we will answer one main question
Why does pressure ulcers happen?
Cells maintain homeostasis but can be stressed by external factors. Adaptive responses include hypertrophy, hyperplasia, atrophy and metaplasia, but severe stress leads to injury and cell death via necrosis or apoptosis. Necrosis involves loss of membrane integrity while apoptosis is genetically programmed cell suicide. Various stresses can cause reversible or irreversible injury through mechanisms like ATP depletion, calcium dysregulation, and damage to organelles and DNA.
Cell injury occurs when homeostasis is disturbed and the limits of adaptive responses are exceeded. There are two main types of cell injury: reversible and irreversible. Reversible injury involves functional and morphological changes that can be reversed if the damaging stimulus is removed, such as reduced ATP and cellular swelling. Irreversible injury cannot be recovered from and leads to cell death, either through necrosis or apoptosis. Common causes of cell injury include oxygen deprivation, physical agents, chemical agents, infectious agents, immunological reactions, genetic defects, and nutritional imbalances. The initial manifestation of most injuries is cellular swelling. Mechanisms of injury involve ATP depletion, mitochondrial damage, calcium influx, reactive oxygen species accumulation, and increased membrane permeability, typically culminating in necrosis or
11. INFLAMMATION DENTISTRY IN SIMPLER TERMS.pptSamkeloKhumalo2
What Is Inflammation?
Inflammation is a process by which your body's white blood cells and the things they make protect you from infection from outside invaders, such as bacteria and viruses.
But in some diseases, like arthritis, your body's defense system -- your immune system -- triggers inflammation when there are no invaders to fight off. In these autoimmune diseases, your immune system acts as if regular tissues are infected or somehow unusual, causing damage.
Pathology is the study of disease through examination of cells, tissues, and organs. The key aspects studied in pathology include the etiology (cause), pathogenesis (mechanism by which the cause produces changes), morphologic changes (structural changes visible microscopically), clinical manifestations (symptoms and signs), prognosis, and complications of diseases. Cellular responses to injury can include adaptations like hypertrophy, hyperplasia, atrophy, and metaplasia, or cell injury/death through necrosis and apoptosis. Necrosis is cell death caused by external factors and is always pathological. Pathology is important for medical education, diagnosis, treatment, and prevention of disease.
Cellular adaptations and injury can occur through various mechanisms:
(1) When cells are exposed to stressors, they may undergo reversible changes like atrophy, hypertrophy, hyperplasia, metaplasia, or dysplasia to adapt. (2) If the stressors are severe or persistent, irreversible cell injury and death through necrosis or apoptosis can result. (3) Cellular injury can be caused by free radicals, hypoxia, physical trauma, chemicals, radiation, or biological agents and can lead to tissue dysfunction or infection if necrosis occurs.
Fracture types - Plaster Of Paris tecniques and ComplicationsVenkatesh Ghantasala
This document discusses fracture types, classifications, and POP techniques and complications. It begins by explaining the purposes of fracture classification systems which include characterizing fractures, guiding treatment, predicting outcomes, and having a common language. It then discusses the history of classifications and different classification systems including fracture-specific, generic, and those based on soft tissue injury. The rest of the document details different fracture types such as based on mechanism, soft tissue involvement, displacement, pattern, fragments, and pediatric fractures. It also provides examples of fracture classifications and eponyms.
This document provides an overview of pathology and the causes and types of cell injury and death. It defines pathology as the study of disease, including the underlying causes (etiology), mechanisms of development (pathogenesis), structural changes in cells and organs (morphology), and functional consequences (clinical significance). The main types of cell injury discussed are reversible injury, where function and structure can return to normal if the stimulus is removed, and necrosis, which is accidental cell death where membranes break down and enzymes digest the cell, causing inflammation. Apoptosis is also mentioned as a programmed form of cell death. Causes of cell injury include genetic defects, hypoxia, toxins, infections, immune reactions, nutritional imbalances, physical agents, and
1. This document provides definitions and clinical features of fractures of the long bones and upper limbs. It discusses the different types of fractures that can occur in these areas, including open vs closed fractures.
2. The clinical presentation of acute fractures typically includes pain, swelling, loss of function, and possible deformity or crepitus. Malunited fractures may cause limitations in range of motion or impingement.
3. The causes of fractures depend on the mechanism of injury, such as a direct blow, twist, or angulation, and can result in different fracture patterns visible on x-rays. High velocity injuries commonly cause comminuted fractures.
Innate and adaptive immunity, B LYMPHOCYTES, T LYMPHOCYTES, ANTIGEN-PRESENTING CELLS, Humoral Immunity But Not Cellular Immunity Is Transferred with Antibody, Exogenous PATHWAY, Endogenous pathway, Differences in the primary and secondary response, Immune Dysfunction and Its Consequences, Immune Response to Infectious Diseases, Viral Infections, Bacterial Infections
1) The document discusses biological responses to materials, including fundamental tissue responses like injury, inflammation, and foreign body reaction, as well as in vivo evaluation of these responses.
2) It first describes the tissue response continuum that occurs after implantation, including injury, blood-material interactions, provisional matrix formation, acute inflammation, and fibrosis or fibrous capsule development.
3) The document then discusses in vivo evaluation of tissue responses to materials, which is necessary to determine biocompatibility and predict potential harm to patients.
A fracture is a break in a bone caused by physical force exceeding the bone's strength. There are different types of fractures including simple/closed fractures where the skin is intact, compound/open fractures where the skin is broken, and transverse fractures which occur at right angles to the bone. Symptoms include pain, swelling, bruising, inability to move or bear weight on the injured area. Fractures are typically diagnosed through physical exam and imaging tests like x-rays. Treatment involves immobilizing the area with splints, casts, traction, or surgery depending on the fracture type to promote healing.
Similar to Histopathology Chapter 2- Responce of the body to injurious .ppt (20)
This document provides an overview of nutritional assessment methods. It discusses both direct and indirect assessment approaches. Direct methods include anthropometric, biochemical, clinical and dietary assessments. Anthropometric assessments measure the body and include indices like BMI, MUAC and skin fold thickness. Biochemical assessments involve laboratory tests. The document focuses on anthropometric methods and their purposes in assessing growth in children and body composition in adults. It provides details on specific anthropometric measurements and derived indices along with their clinical meanings and cut-off points.
This document defines key terms related to human nutrition including nutrition, food, diet, nutrients, and malnutrition. It provides a brief history of the discovery and development of nutrition as a scientific discipline. Important figures like Hippocrates, da Vinci, and Lavoisier contributed early understandings. Major advances occurred in the 19th and 20th centuries including the discovery of vitamins and minerals. The document emphasizes the importance of nutrition for growth, development, and health and discusses its significance in Ethiopia where malnutrition remains a major public health burden affecting vulnerable groups like women and children.
1 Introduction to HEtrry & HP - Copy.pptAmanuelMerga
The document discusses concepts of health education and health promotion. It defines the negative and positive models of health and explains that health education aims to promote healthy behaviors through voluntary actions. Health promotion combines health education and environmental supports to influence conditions for health. The rationale for health education includes addressing communicable and chronic diseases, promoting prevention over cure, and achieving health-related Millennium Development Goals. Health education is also important for primary healthcare, community participation, and Ethiopia's national health policy.
Histopathology chapter 7,8-cytology, Ic (1).pptAmanuelMerga
This document discusses cytology techniques used in cytopathology. It begins by defining cytopathology as the study of cells from various body sites to determine the cause of disease. The main applications of cytopathology are screening for early cancer detection, diagnosing symptomatic cancer, and following up patients treated for cancer. The different cytopathologic methods discussed are fine-needle aspiration cytology, exfoliative cytology, and abrasive cytology. Fine-needle aspiration cytology involves aspirating cells from organs using a thin needle, while exfoliative cytology examines spontaneously shed cells in body fluids. Abrasive cytology dislodges cells from body surfaces using various tools.
This document summarizes the complement system. It describes the three main pathways of complement activation: the classical pathway activated by antibody-antigen complexes, the alternative pathway activated by microbial surfaces, and the lectin pathway activated by mannose-binding lectin. All three pathways generate C3 and C5 convertases and ultimately form the membrane attack complex. Complement activation leads to opsonization, inflammation, and cell lysis. The complement system is tightly regulated by several fluid-phase and membrane-bound regulatory proteins to prevent damage to host cells.
This document describes several medically important arthropods including flies, sandflies, fleas, and cockroaches. It provides details on their classification, morphology, life cycles, behaviors, and roles in disease transmission. Regarding flies, it notes that houseflies can transmit pathogens mechanically and cause myiasis. For sandflies, it identifies several disease-transmitting species and describes their morphology, life cycle, and medical importance in transmitting leishmaniasis. Fleas are described as ectoparasites of mammals that can cause irritation and transmit plague and epidemic typhus. Control methods for these arthropods focus on environmental modification and use of insecticides.
Blood is composed of plasma and formed elements including red blood cells, white blood cells, and platelets. Red blood cells transport oxygen and carbon dioxide, white blood cells provide immunity, and platelets help with clotting. Hematopoiesis is the process where blood cells develop from pluripotent stem cells in the bone marrow. In fetuses, blood cell production occurs first in the yolk sac, then the liver and spleen, and eventually primarily in the bone marrow after birth. The document discusses the composition, functions, and development of the various blood cell types.
This document discusses methods for summarizing data, including measures of central tendency and dispersion. It defines the mean, median, and mode as common measures of central tendency, and how to calculate each. Measures of dispersion discussed include range, variance, standard deviation, and the coefficient of variation. The document provides examples of calculating and interpreting these various summary statistics.
4Probability and probability distributions (1).pptxAmanuelMerga
Draw the figure. We want the area between -2.55 and +2.55.
Look up the area to the left of -2.55 in the table. It is 0.0049. Also look up
the area to the left of +2.55. It is 0.9937. Subtract these two areas. 0.9937
- 0.0049 = 0.9888. Hence, the probability that a z picked at random will
have a value between -2.55 and +2.55 is 0.9888 or 98.88%
This document discusses streptococcal infections and serological tests for streptolysin O (SLO) and antistreptolysin O (ASO). It describes SLO as a bacterial toxin produced by S. pyogenes that causes hemolysis. SLO is released during infection and detected by measuring ASO antibodies. Two main tests for ASO are discussed: a latex agglutination test that screens for levels over 200 IU/ml, and a quantitative tube test that determines the antibody titer.
This document describes the classification, morphology, behaviors, and medical importance of flies, sandflies, fleas, and cockroaches. It notes that flies belong to the order Diptera and includes disease-transmitting species like houseflies. Sandflies are in the order Psychodidae and can transmit leishmaniasis. Fleas are ectoparasites that belong to the order Siphonaptera and transmit plague and epidemic typhus. All four undergo complete metamorphosis from egg to larva to pupa to adult. As vectors, they can transmit pathogens mechanically or biologically and cause diseases and infections in humans. Prevention focuses on environmental modification and use of insecticides, screens, and personal protection measures
Tsetse flies are restricted to sub-Saharan Africa and are vectors of both human and animal African trypanosomiasis. There are 31 species of tsetse flies in the genus Glossina, which can be separated into three groups based on morphology, ecology, and behavior. Important vectors include G. palpalis, G. fuscipes, G. tachinoides, G. morsitans and G. pallidipes. Tsetse flies have a proboscis and feed on the blood of humans and various mammals. They are unique among flies in being viviparous, giving birth to live larvae.
The document discusses the family Psychodidae, specifically the genus Phlebotomine sand flies. It describes the three subgenera (Phlebotomus, Lutzomyia, and Sergentomyia), noting that Phlebotomus and Lutzomyia are important vectors for disease. It provides details on the morphology and life cycle of phlebotomine sand flies, including their pale coloring, humped thorax, maxillary palps, and wing structure as adults. It also discusses their medical importance as vectors of leishmaniasis and other diseases.
Health informatics is the field concerned with the optimal use of information aided by technology to improve health care. It involves the intersection of information science, computer science, and health care. Public health informatics applies computer and information science to public health practice, research, and learning. Health informatics provides information to make better health care decisions and aims to acquire, manipulate, store, display, and communicate information to improve health outcomes.
share - Lions, tigers, AI and health misinformation, oh my!.pptxTina Purnat
• Pitfalls and pivots needed to use AI effectively in public health
• Evidence-based strategies to address health misinformation effectively
• Building trust with communities online and offline
• Equipping health professionals to address questions, concerns and health misinformation
• Assessing risk and mitigating harm from adverse health narratives in communities, health workforce and health system
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Histopathology Chapter 2- Responce of the body to injurious .ppt
1. September 4, 2023 1
CHAPTER TWO
RESPONCE OF THE BODY TO INJRIOUS AGENTS
2. 2
September 4, 2023
2.1 RESPONSE OF THE BODY TO
INJURIOUS AGENTS
Since pathology deals with disease, it is
appropriate to consider some of the ways
in which the body responds to injurious
agents (bacteria, viruses, trauma, etc.).
Initially, the body employs one or more
of its natural defense mechanisms.
3. 3
September 4, 2023
These defenses include
Physical barriers (skin, mucous membranes,
etc.)
Detoxification (neutralization of toxin by
liver enzymes, etc.)
Adaptive compensation (increase in heart
size when it is overloaded, etc.)
Immunologic response (reaction of
antibodies with antigens, etc.)
Cellular response (movement of neutrophils
toward an injured site, etc.) and others.
4. 4
18 August 2011
The natural bodies defenses may completely
neutralize or destroy the injurious agent before
lesions and/or disease develop.
However, once lesions and/or disease are
detected, it can be assumed that natural body
defenses were inadequate or at least delayed in
their response.
As a result, an inflammatory response may
develop.
5. 5
September 4, 2023
Mild injury causes stress on the cell but not cell
death.
Such injury is known as reversible injury, such
cells develop structural or functional changes to
overcome injury known as adaptation.
When injury is severe enough it causes death of
cell termed irreversible injury.
Changes occurring in dead cells are known as
necrosis.
6. 6
September 4, 2023
The term “Necrosis” is used to describe structural changes
occurring in dead cells within living tissue.
For example when blood supply to heart is reduced heart
muscle suffer damage called "Ischemia" and presents as
severe pain and it recovers when blood supply is restored.
But when blood is blocked for more than 10 min, then cells
in that part of heart die.
When we start physical exercise our muscles sense the
excess workload and increase their size to avoid trauma this
is called "hypertrophy".
When we stop using a muscle (e.g. after fracture) the muscle
cells become thin (atrophy).
7. 7
September 4, 2023
Cellular Adaptations
Cells are the structural and functional units of
tissues and organs.
They are capable of adjusting their structure
and functions in response to various
physiological and pathological conditions.
This capability is called cellular adaptation
8. 8
September 4, 2023
Various Types of Adaptations
Cells may undergo various adaptations in physiological
and pathological conditions.
These are controlled by complex molecular mechanisms.
The following are common types of cellular adaptation:
Atrophy
Hypertrophy
Hyperplasia
Metaplasia
9. 9
September 4, 2023
Atrophy
Shrinkage of cells.
Classified as:
Physiologic--due to decreased work load
(e.g., decreased size of uterus following
child birth).
Pathologic--primarily due to denervation
of muscle, diminished blood supply,
nutritional deficiency, Aging, Pressure,etc.
10. 10
September 4, 2023
Hypertrophy
Increase in the size of cells which results in
enlargement of the organs.
It is mostly seen in cells that cannot divide,
such as skeletal muscle , and cardiac muscle
(hypertension).
These changes usually revert to normal if the
cause is removed.
11. 11
September 4, 2023
Hyperplasia
Increased number of cells in an organ or
tissue.
Hyperplasia may sometimes co-exist with
hypertrophy.
Hyperplasia can be classified as:
Physiologic--hormonal (e.g., breast and
uterus during pregnancy)
Compensatory--regeneration of liver
following partial hepatectomy.
Pathologic--excessive hormonal
stimulation in response to viral infection
(papilloma viruses); neoplasms
13. 13
September 4, 2023
Metaplasia
Transformation or replacement of one adult
cell type to another adult cell type. E.g. the
change from columnar to squamous cells in
respiratory tract.
Metaplastic changes usually result from
chronic irritation.
Metaplastic changes seem to precede the
development of cancer, in some instances.
14. 14
September 4, 2023
Cell injury
If the cells fail to adapt under stress, they
undergo certain changes called cell injury.
Cell injury may be divided to
Reversible cell injury
Irreversible cell injury
The affected cells may recover from the injury
(reversible) or may die (irreversible)
16. 16
September 4, 2023
1. HYPOXIA:
Hypoxia refers to a lack of oxygen which is
probably the most common cause of cell
injury and disease.
It may be the ultimate mechanism of
damage initiated by a variety of physical,
chemical and biological agents.
17. 17
September 4, 2023
HYPOXIA…cont’d
(1) Loss of their blood supply (e.g.
ischemia subsequent to the presence of a
thrombus in the lumen of a vessel),
(2) Depletion of the oxygen-carrying
capacity of the blood (e.g. carbon
monoxide poisoning)
(3) Poisoning of the oxidative enzymes
within cells (e.g. cyanide poisoning in
which cytochrome oxidase is inactivated).
18. 18
September 4, 2023
2 PHYSICAL INJURIES:
Physical agents responsible for cell/tissue
damage include trauma, pressure,
obstructions of hollow organs, malpositions,
thermal factors, changes in atmospheric
pressure, light, electricity and radiation.
2.1 MECHANICAL TRAUMA:
Is usually an injury caused by sudden
violent physical forces in which cells/tissues
are torn or crushed.
19. 19
September 4, 2023
The types of trauma include:
Contusion (bruise) refers to an injury in which
the covering skin is intact, but the underlying
tissues are damaged.
Abrasion refers to an injury similar to a
contusion, but one in which the skin is broken.
Incision refers to an injury produced by a
sharp object, resulting in little tissue damage.
Laceration refers to an injury resulting from
the tearing of tissues with a blunt object.
20. 20
September 4, 2023
The types of trauma…cont’d
Perforation refers to a wound in which the
point of entry of the mechanical force is small.
Rupture refers to an injury in which tissues are
stretched until the fibers are disrupted (rupture
occurs in hollow organs or in the capsule of
such organs as the kidneys, liver and spleen or
in muscles and tendons).
Fracture refers to a break in a hard substance
such as bone or cartilage.
Luxation (dislocation) refers to an injury of an
articulation in which there is displacement of
bone making up the articulation.
21. 21
September 4, 2023
2.2 PRESSURE:
Results in mild or less violent injuries which usually
take place over a prolonged period of time.
ulcers which occur over bony prominences of the
body (tuber coxae, zygomatic arch, etc.) of an
animal recumbent for several days is a classical
example of pressure injury.
Also, pressure injury occurs when casts or bandages
are applied too tightly or when neoplasms,
abscesses, etc. encroach upon parenchymal organs.
22. 22
September 4, 2023
2.3 OBSTRUCTION OF HOLLOW ORGANS:
Hollow organs may be obstructed and
subsequently injured by changes within the lumen
(rubber ball, etc.), pressure from outside the organ
(neoplasm, etc.) or by changes within the wall of
the organ (abscesses, neoplasm, etc.)
The term "stenosis" refers to any narrowing of the
lumen of a hollow organ; whereas the term
"stricture" is reserved for a form of stenosis
caused by contraction of fibrous connective tissue
(scar tissue) in the wall of an organ.
23. 23
September 4, 2023
2.4 MALPOSITION:
Refers to the displacement of an organ or part that results in
cell and/or tissue injury. The types of malpositions include
Volvulus refers to the rotation of an organ or part around its
mesenteric base of attachment. Loops of intestine are
usually involved and the twist is usually more than 180
degrees.
Torsion refers to the rotation of an organ or part along its
own long axis. The intestine, uterus, lung lobes, etc. may be
involved.
Intussusception refers to the telescoping of one portion of a
hollow organ into another portion (e.g., a portion of the
intestine is forced inside the segment just posterior to it).
Prolapse is the appearance of an organ or portion of an
organ at a natural or artificial body opening.
24. 24
September 4, 2023
2.5 THERMAL INJURIES
Extremes of temperature, such as freezing and
burning, cause injury in several ways (direct
damage, vasconstriction, etc.).
Burns refer to lesions produced directly by heat.
Heat retention (heatstroke/sunstroke) occurs
when animals are unable to eliminate sufficient
heat to maintain body temperature at a level
compatible with life. Subsequently, cells and
tissues are injured.
25. 25
September 4, 2023
THERMAL INJURIES…cont’d
Freezing of tissues occurs when the body is
exposed to very low temperatures.
When tissues freeze, there is damage to blood
vessels, formation of thrombi and subsequent
interference with circulation.
Thrombi -is the plural of thrombus.
A thrombus, or blood clot, is the final product
of the blood coagulation step in hemostasis.
26. 26
September 4, 2023
2.6 LIGHT:
Sunburn or overexposure to light is rare in animals due
to skin pigmentation and protection by the hair coat.
Photosensitization with damage to the skin occurs as the
result of the action of sunlight on fluorescent pigments
(phylloerythrin, etc.) in the skin.
Phylloerythrin is photodynamic substance produced in
the body, a derivative of chlorophyll.
Normally, the phylloerythrin is secreted into the intestine
by the biliary system and get excreted.
But due to failure or damage to biliary system,
phylloerythrin enters the systemic circulation and is
accumulated under the skin.
27. 27
September 4, 2023
2.7 ELECTRICITY
Strong electrical currents from artificial sources
or from lightning cause burns or result in somatic
death.
An animal produces a short circuit with his body
between two conductors.
The effects of electricity include burning of
tissues, hemorrhages, and/or death due to
interference with cardiac and respiratory
functions.
28. 28
September 4, 2023
2.8 RADIATION:
Injuries produced by ionizing radiation depend
upon the type of radiation (alpha, beta, gamma,
etc.) and the susceptibility of the cell or tissue
exposed.
Rapidly growing cells (e.g., lymphoid cells)
are quite susceptible; whereas, more slow
growing cells (e.g., cells of bone) are more
resistant.
29. 29
September 4, 2023
3. CHEMICAL INJURIES:
The list of chemical that may produce
cell/tissue injury challenge compilation.
Simple chemicals such as glucose or salt in
hypertonic concentrations may cause cell
injury by deranging the fluid and electrolyte
homeostasis of cells; even oxygen in high
concentrations is severely toxic.
30. 30
September 4, 2023
CHEMICAL INJURIES…cont’d
On the other hand, the levels of toxicity of certain
substances are so high that they are known as
poisons and trace amounts (arsenic, cyanide,
mercury salts) may destroy a sufficient number of
cells within minutes or hours to cause death.
Under certain conditions, toxic materials may be
formed within the body and subsequently cause cell
damage.
Severe burns, uremia, and gangrene may be
associated with endogenous poisons.
31. 31
September 4, 2023
4. BIOLOGICAL AGENTS
Biological agents are important causes of
cell injury and death.
They include
Bacteria,
Viruses,
Rickettsiae,
Fungi and
Parasites.
32. 32
September 4, 2023
5 .IMMUNOLOGIC REACTIONS:
Immunological reactions maybe life-saving or
lethal.
Some immune reactions may cause cell injury
and death (anaphylactic reaction to a foreign
protein or drug, etc.).
Also, there is evidence that an immune
reaction against "self-antigens" (autoimmunity)
is the cause of certain diseases in animals.
33. 33
September 4, 2023
6. GENETIC DEFECTS
Genetic defects are important causes of
cellular injury. E.g. Sickle cell disease
7. NUTRITIONAL IMBALANCES
There may be deficiencies (e.g., in proteins or
specific vitamins), excesses (e.g., in lipids
causing atherosclerosis) or lack of an
appropriate balance.
34. 34
September 4, 2023
Cell Death-Irreversible injury
Death of cells occurs in two ways:
Necrosis--(irreversible injury) changes
produced by enzymatic digestion of dead
cellular elements
Apoptosis--vital process that helps eliminate
unwanted cells--an internally programmed
series of events effected by dedicated gene
products
35. 35
September 4, 2023
Patterns of Necrosis In Tissues or Organs
As a result of cell death the tissues or organs
display certain macroscopic changes:
Coagulative necrosis: the outline of the dead
cells are maintained and the tissue is somewhat
firm. Example: Myocardial infarction.
Liquifactive necrosis: the dead cells undergo
disintegration and affected tissue is liquified.
Example: cerebral infarction.
36. 36
September 4, 2023
Patterns of Necrosis…cont’d
Caseous necrosis: a form of Coagulative
necrosis (cheese-like). Example: Tuberculosis
lesions.
Fat necrosis: enzymatic digestion of fat.
Example: necrosis of fat by pancreatic
enzymes.
Gangrenous necrosis: Necrosis (secondary to
ischemia) usually with superimposed infection.
Example: necrosis of distal limbs, usually foot
and toes in diabetes.
39. 39
September 4, 2023
AUTOLYSIS
Lysis of tissues by their own enzymes, following
the death of the organism.
Therefore, the key difference is that there is no
vital reaction (i.e., no inflammation).
Autolysis is essentially rotting of the tissue.
Early autolysis is indistinguishable from early
coagulative necrosis due to ischemia, unless the
latter is focal.
40. 40
September 4, 2023
APOPTOSIS
This process helps to eliminate unwanted cells by an
internally programmed series of events effected by
dedicated gene products.
Morphology of Apoptosis
Shrinkage of cells
Condensation of nuclear chormatin peripherally under nuclear
membrane
Formation of apoptotic bodies by fragmentation of the cells and
nuclei. The fragments remain membrane-bound and contain cell
organelles with or without nuclear fragments.
Phagocytosis of apoptotic bodies by adjacent healthy cells or
phagocytes.
Unlike necrosis, apoptosis is not accompanied by inflammatory
reaction
41. 41
September 4, 2023
Mechanisms of Apoptosis
Apoptosis can be induced by various
factors under both physiological and
pathological conditions.
It is an energy-dependent cascade of
molecular events which include protein
cleavage by a group of enzymes, protein
cross-linking, DNA breakdown.
42. 42
September 4, 2023
Mechanisms of Apoptosis…cont’d
Apoptosis goes through several complex
phases.
To put it simply, abnormal mitochondrial
membrane permeability is a crucial event
which allows escape of cytochrome-c into the
cystosol which, in turn, activates proteolytic
enzymes leading to the execution of the
process.
The final phase is the removal of dead cell
fragments by phagocytosis without
inflammatory reactions.
45. 45
September 4, 2023
Ageing
Cellular Aging
Many cell functions decline, and morphologic
changes occur with aging.
Ageing is thought to be influenced by an intrinsic
molecular program, called the "programmed
ageing hypothesis."
It states that sequential shortening of telomeres
(the natural ends of chromosomes) may lead to
loss of genes, causing cellular ageing.
Ageing is also thought to be influenced by
cumulative effects of various extrinsic factors.
46. 46
September 4, 2023
2.2 Inflammation
Inflammation is "dynamic response of vascularized
tissues to injury".
It is a complex multi step process of tissue response to
injury.
The purpose of inflammation is to defend against
injurious agent and start healing & repair of injured tissue.
Inflammation is an important part of body's defense
mechanisms.
Inflammation brings together defense forces such as
WBC, antibodies and other chemicals apart from bringing
more nutrients and healing factors to the site of injury.
47. 47
September 4, 2023
An abscess on the skin, showing the redness and swelling
characteristic of inflammation.
Black rings of necrotic tissue surround central areas of pus
48. 48
September 4, 2023
Inflammation is one of the primary host defense
mechanisms against all forms of tissue damage.
It can best be defined as the "vascular and cellular
response of living tissue to injury."
The "vascular response" is reflected by changes in the
size of blood vessels as well as by changes in the flow
rate of blood to the damaged tissue (arterioles and
capillaries dilate resulting in an increased blood
flow).
The "cellular response" is reflected by the movement
of inflammatory cells (neutrophils, etc.) from the
lumen of blood vessels into the damaged tissue site.
(i.e., neutrophils attracted to the damaged tissue site
will attempt to ingest and destroy the injurious agent.)
49. 49
September 4, 2023
Inflammation…cont’d
Thus, the inflammatory process serves to
dilute, neutralize, destroy or wall-off the
injurious agent as well as damaged
parenchymal cells.
In other words, a complex series of events are
initiated which, as far as possible, heal and
reconstitute the damaged tissue.
It should be remembered that inflammation
and repair of tissues occur together.
50. 50
September 4, 2023
Inflammation…cont’d
Repair is the process by which dead cells are
replaced by viable cells.
Sometimes repair is accomplished by
regeneration of native parenchymal cells.
More often, however, it is accomplished by
the replacement of native parenchymal cells
by fibrous connective tissue.
51. 51
September 4, 2023
Inflammation…cont’d
On the whole, inflammation and repair are
beneficial to the host.
In their absence, infections would go unchecked,
burns would not heal, and wounds would remain
rotten open sores.
However, under certain circumstances,
inflammation and repair may be harmful to the
body.
Also, the inflammatory process and other body
defenses may not be effective in controlling an
infection and somatic death follows.
52. 52
September 4, 2023
Inflammation…cont’d
Understand that although inflammation is a
protective defence mechanism, inflammation causes
pain and distress to the patient
Excess inflammation or inflammation due to
abnormal immune reaction such as allergy can be
very destructive. Example Asthma is inflammation
of respiratory mucosa due to hypersensitivity
reaction.
Inflamed tissue are named by adding suffix-itis to
anatomic site of involvement e.g. Appendicitis,
conjunctivitis, etc.
53. 53
September 4, 2023
Classification of inflammation
Inflammation can be acute or chronic
Acute Chronic
Less tissue destruction Severe tissue destruction
Mainly polymorphs Mainly mononuclear cells
Less than a week or Many weeks, months, years
Exudative Proliferative
Self resolving Irreversible
55. 55
September 4, 2023
Some terms pertinent with inflammation:
1. Exudates: are fluids, cells, or other cellular
substances that are slowly discharged from
blood vessels usually from inflamed tissues.
Serous exudate- more fluid (water), early or mild
damages
Fibrinous exudates – more protein, sever damage
(high molecular weight protein e.g. fibrinogen)
Purulent – more infiltrates, mainly polymorphs (pus
cells)
Hemorrhagic – severe vascular damages eg. anthrax
56. 56
September 4, 2023
2. Transudate: are fluids that pass through a
membrane or squeeze through tissue or into the
extracellular space of tissues.
Transudates are thin and watery and contain few
cells or proteins. [Specific Gravity (SG) < 1.015
transudate and > 1.020 exudate]
3. Abscess: Localized tissue destruction with pus.
Components of pus include: polymorphs (dead and
intact), Tissue debris and macrophages (dead &
intact)
4. Empyema: Pus in preformed body space eg.
pleura, joints, G. bladder etc
5. Fibrosis: Fibroblast proliferation depositing
variable amount of collagen and evolves to scar.
57. 57
September 4, 2023
Property
Transudate Exudate
Appearance Clear Cloudy
Total Protein (g/dl) < 3 >3
Specific gravity <1.018 >1.018
Cell count (/µl) < 10,000 >10,000
Clot No Yes
58. 58
September 4, 2023
2.3 INTRODUCTION TO NEOPLASIA
Neoplasm: (Literally: New growth)
An abnormal tissue mass whose growth
exceeds and is uncoordinated with that of
adjacent normal tissue and persists after
cessation of the stimuli that provoked it.
Colectomy specimen
containing a malignant
neoplasm, namely an
invasive colorectal
carcinoma (reddish,
irregularly-shaped tumor)
60. 60
September 4, 2023
NEOPLASIA
A neoplasm results from the derangement of
normal growth control mechanisms.
In some manner, the balance between cell
division and cell death is upset.
Hyperplasia can result as a reaction to
environmental influences such as chronic
inflammation,
But a neoplasm's growth is partially or totally
independent of such external influences.
61. 61
September 4, 2023
BASIC TERMINOLOGY
Tumor - A swelling; could be due to any number
of causes
Neoplasia - A relatively autonomous growth of
tissue; the growth of which exceeds and is
uncoordinated with that of normal tissue and
persists in some manner after cessation of the
inducing stimulus.
62. 62
September 4, 2023
BASIC TERMINOLOGY…cont’d
Benign Neoplasm
A neoplasm that grows without invading
adjacent tissue or spreading to distant sites.
It is usually fairly well-circumscribed due to
the lack of invasion of surrounding tissues.
Malignant Neoplasm
A neoplasm that invades the surrounding
normal tissue and usually spreads to distant
sites given sufficient time.
63. 63
September 4, 2023
Differentiation
Differentiation (of a neoplasm) refers to the
extent to which the cells comprising the neoplasm
resemble comparable normal cells both
morphologically and functionally.
The tissue type represented by the tumor.
Well-differentiated tumors resemble the tissue of
origin while poorly differentiated tumors may
only be identifiable by the expression of cell
markers or by extremely focal and subtle
histologic and/or cytologic findings.
64. 64
September 4, 2023
Anaplasia
Anaplasia Denotes a lack of differentiation
in a malignant neoplasm, making it difficult
to determine the tissue or cell of origin.
1. Anaplasia is evidenced by wide variety
in size, shape, staining and organization of
malignant cells within a neoplasm
2. Anaplasia is not a characteristic of
benign neoplasms
65. 65
September 4, 2023
Dysplasia
The term "plasia" means growth.
Dysplasia means disordered growth.
Alterations in size, shape, staining
characteristics of cells and unusual proliferation
of cells characterized by nuclear enlargement
and failure of maturation and differentiation.
67. 67
September 4, 2023
Dysplasia… cont’d
Dysplasia is recognized by alterations in the
appearance of cells (cytology).
Dysplastic cells have some of the features of
malignant cells but the changes are less
pronounced.
68. 68
September 4, 2023
Reactive atypia
State of being not typical.
An abnormal cellular appearance and an
increased mitotic rate associated with a
reparative state due to environmental
influences such as inflammation.
Reactive atypias are non-neoplastic.
Once the environmental influence goes
away, the atypia disappears.
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Reactive atypia
The atypia general involves enlargement
of both the cytoplasm and nucleus and an
increased prominence of nucleoli.
These features reflect the increased
metabolic activity of the cells.
Malignant criteria such as extremely
irregular nuclear membranes are absent.
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Carcinoma in situ (cis)
Full-thickness dysplasia extending from the
basement membrane to the surface of the
epithelium.
Applicable only to epithelial neoplasms.
If the entire lesion is no more advanced than CIS,
then the risk of metastasis is zero.
This is because there are no blood vessels or
lymphatics within the epithelium above the
basement membrane.
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Carcinoma in situ (cis)…cont’d
Invasion: Growth into the surrounding
tissue by direct expansion.
Metastasis: Spread of tumor to distant
sites by lymphatic or hematogenous
routes.
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Tumor Nomenclature
A. Basic Rule #1
1. Carcinoma- from epithelial tissue.
Eg. Squamous cell carcinoma from skin
Adenocarcinoma- epith of glands (most colon,
breast, lung tumors)
common and deadly form of cancer
2. Sarcoma- from mesynchymal cells (bone,
muscle, fibroblasts)
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B. Basic Rule #2
1.Benign: “-oma” eg. fibroma
2. Malignant: “-carcinoma” or “-sarcoma”
eg. fibrosarcoma
Exceptions: eg. Lymphoma
(malignant lymphocytes)
77. The next chapter 3 and 4 will be
your assignement
You will prepare hard cope and soft cope for
presentation
Document sub. Date will be 20/3/14/presentation
date will be 22/3/14
Your first test will be 29/3/14
1. Histophatological technique
2. Handling of biopsy specimen
3. Compound of fixation
4. microtome
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Editor's Notes
September 4, 2023
Changes due to reversible injury=adaptation, whereas changes due to irreversible injury=necrrosis.