Pathology:a. The Study of Diseaseb. A Clinical Specialty

Why the teaching of concepts and mechanisms of disease is important at the high school level.

The basic principles of general pathology.

Application of the principles and methods of pathology to the diagnosis, as well as the understanding of disease.

The potential career pathways for pathologists.

Biology Pathology

• Health Disease• Order Disorder• Symbiosis Parasitism• Homeostasis Host Defense• Growth Neoplasia• Circulation Infarction• Hormones Endocrine Diseases

• Confront disease in their daily lives• Inundated by disease (mis)information (news, entertainment)• New threats to be faced (emerging pathogens, bioterrorism)• Increasing complexity of medical care (informed consumers)

WHY INCLUDE DISEASE PRINCIPLES IN HIGH SCHOOL CURRICULUM?

A. IT’S IMPORTANT

B. IT’S INTERESTING• Focus on themselves & their bodies (as well as frogs and paramecia)

Integration of both sides of the forceC. IT’S REINFORCING

• Observation & Classification• Conceptualization & Abstraction,• Explanation & Prediction• Application• (Career choices)

GENERAL PATHOLOGY There are general principles that apply to

the various diseases

• Finite set of patterns of injury • Similar physiologic and morphologic

consequences of different injuries • Small number of reparative processes

HOST DEFENSE

Injury

Protective Response

RepairInflammation

ImmunityFibrosisRegenerationResolution

mediators

Inflammation is an immediate reaction to damage that limits it directly, helps focus an immunereaction, and sets the stage for subsequent repair.

INFLAMMATION & IMMUNITY

INFLAMMATION vessels serum factors cells

IMMUNE RESPONSE antibodies activated cells cytokines

Inflammatory/Immune Cells

Cell-MediatedCell-MediatedCell-MediatedCell-Mediated

Antibody-MediatedAntibody-MediatedAntibody-MediatedAntibody-Mediated

EFFECTOR FUNCTIONS OF THE IMMUNE SYSTEM

Cytokine-Mediated

•Cell destruction•Cell proliferation•Cell movement•Cell differentiation•Cell activation

•Precipitation•Neutralization•Complement activation•Mask Receptors•Enhance Phagocytosis•Activate leukocytes•ADCC

Cytotoxic T cellsActivated NK CellsActivated Macrophages

LYMPHOCYTES LEAVING A BLOOD VESSEL

CANCER

POSITION TITLE: MALIGNANT CELLJob Description

• Survive and proliferate locally• Invade adjacent tissue• Induce supporting stroma and blood supply• Gain access to the circulation

a. Cross basement membraneb. Cross endothelium

• Leave circulationa. Cross endotheliumb. Cross basement membrane

• Colonize new location• Survive and proliferate at distant site

GROSS PHOTOGRAPH MICROPHOTOGRAPH

CANCER OF PANCREAS

THE KISS OF DEATH

CAUSES OF CANCER

SOME SPECIFIC CAUSES

•Sweeping chimneys•Using aniline dyes•Smoking cigarettes•Building ships in WWII•Renovating old houses

SOME GENERAL CAUSES

•Breathing•Drinking•Eating•Working•Sunshine•Sex•Doctors

SOME UNDERLYING CAUSES

•Loss of negative growth signals•Excessive production of growth factors•Decreased (normal) cell death•Loss of spatial constraints

Patient

Physical Exam

RadiologistSurgeon

Pathologist

Internist

Normal Breast

MAMMOGRAM

BREAST CANCER

DIAGNOSTIC SURGICAL PROCEDURES

• Fine Needle Aspiration (FNA)

• Needle Core Biopsy

• Excision Biopsy

CANCER CELLS BY CYTOLOGY

TISSUE EXAMINATION

PROCESSING

SLIDE PREPARATION

FINAL DIAGNOSISS-01-10

BREAST CARCINOMA- THROUGH MICROSCOPE

DETECTION & IDENTIFICATION METHODS

ANTIBODIES AS DETECTION AGENTS

• Immunohistochemistry

• Immunofluorescence

DNA AS PROBES

• In situ hybridization

• DNA sequencing

• Polymerase Chain Reaction

Amplification of signal with biotin

IMMUNOHISTOCHEMISTRY

FLUORESCENT IN SITU HYBRIDIZATION (FISH)

MOLECULAR IDENTIFICATION

•Cellular phenotypes•Differentiation stages•Tumor classification•Gene activation & RNA expression•Detection of proteins, nucleotide sequences, mutations•Exogenous pathogens•Altered proteins

APPENDIX: INTEGRATION OF PATHOLOGY AND BIOLOGY CURRICULUM

UNIT 1: WHAT IS BIOLOGY?Module 1: Basic Aspects of Pathology

•The relationship between homeostasis and response to damage•Self-protection: inflammation, immunity, & repair•How organisms adapt to functional losses•How we study disease, and what tools are available•The use of biological principles to treat disease

UNIT 2: PRINCIPLES OF ECOLOGYModule 2: The Ecology of Disease

•Distinguishing self from non-self•How populations resist injury by adaptation•How populations resist injury by evolution•Infectious diseases as predators•How do humans experience symbiosis and parasitism

INTEGRATION OF PATHOLOGY & BIOLOGY CURRICULUM

UNIT 3: THE LIFE OF CELLSModule 3: Cellular Pathology

•How does the cell maintain a boundary around it, other cells & the outside world?

•What happens when these boundaries are breached?•Susceptibility of organelles to damage & disturbances of cellular metabolism•What triggers a cell to divide and how can this stimulus become defective?•What are the consequences of uncontrolled cell proliferation?•How we study disease, and what tools are available?•The use of biological principles to treat disease

UNIT 4: GENETICSModule 4: The Genetics of Disease

•How can diseases be inherited?•Does heredity play a role in diseases that are not inherited?•Do different populations have different risk factors?•The difference between germ cell and somatic cell mutation•What are the principles of genetic engineering?

INTEGRATION OF PATHOLOGY & BIOLOGY CURRICULUM

UNIT 5: EVOLUTIONModule : Evolutionary Forces in Disease

•The forces driving molecular evolution in animals & pathogens•Information transfer without DNA (prions & retroviruses)•Do disease organisms co-evolve with their hosts and/or evolve

to take advantage of new hosts•What are the differences between evolution & genetic engineering?

UNIT 6: DIVERSITY OF LIFEModule 6: diversity of Disease

•What are the different kinds of pathogenic agents (pathogens)?•How do we classify infectious organisms?•Differences in the response to different kinds of pathogens•How do different individuals respond differently to

the same or similar pathogens?