W1L1 - Inflammation and Healing

Instructor: Kadison
Structure of Course:
- Lecture One: Inflammation and Wound Healing
- Introduction to Neoplasia (Cancer)
- Future Topics: Blood Disorders, Gastrointestinal Disorders, Musculoskeletal Disorders, Endocrinology (Two combined lectures)

Definition: Pathophysiology is the study of the functional changes that occur due to disease processes at various stages.
Relation to Physiology and Pathology:
- Physiology: Covers normal bodily processes and mechanisms.
- Pathology: Describes conditions observed during disease states.

Current advances allow understanding of pathophysiological processes at sub-molecular and subcellular levels.
Importance for pharmacy professionals: Interventions depend on knowledge of disease stages and mechanisms.

Definition: Inflammation is the body's first response to injury or disease.
Purpose:
- Neutralize harmful agents.
- Stop further damage.
- Clean and repair damaged tissue.
Complexity of Response: Varies based on type and severity of injury (e.g., pinprick vs. infection).

Acute Inflammation:
- Initial response; occurs quickly and usually resolves within days.
Chronic Inflammation:
- Long-term tissue reaction; can last for months to years and may lead to ongoing damage (e.g., autoimmune diseases).

Five Cardinal Signs:
1. Redness (rubor)
2. Heat (calor)
3. Pain (dolor)
4. Swelling (tumor)
5. Loss of function (functio laesa)
Example: Injury to the knee can cause all five signs due to increased blood flow and fluid accumulation.

Localized Inflammation: Occurs at a specific site (e.g., appendicitis for appendix inflammation).
Generalized Inflammation: Involves multiple sites across the organism (e.g., systemic infections).
Phases of Inflammatory Response:
1. Vascular Phase: Blood vessels become permeable and secrete mediators at the injury site.
2. Cellular Phase: Inflammatory cells exit vasculature to reach injury site.

Cells have surface receptors that recognize pathogens or injury-related insults.
Chemical Mediators (cytokines) activate inflammatory pathways, leading to transcription of inflammatory proteins.
Inflammatory responses can be beneficial for repair or pathological if excessive.

Vascular Factors:
- Pro-inflammatory mediators lead to vasodilation and increased permeability.
- Types of exudate:
- Serous Exudate: Watery, low protein.
- Fibrinous Exudate: High protein, involved in clotting.
- Purulent Exudate: Pus-forming due to infection.
- Hemorrhagic Exudate: Blood due to trauma.
Cell Types Involved:
- Leukocytes: White blood cells involved in the inflammatory response divided into:
- Monocytes: Differentiate into macrophages, capable of phagocytosis.
- Polymorphonuclear Cells (Polymorphs): Include neutrophils, eosinophils, and basophils involved in phagocytosis and mediator secretion.
- Lymphocytes: Involved in adaptive immunity, further categorized into B and T cells.

Complement Proteins: Activated by injury, facilitating chemotaxis and destruction of pathogens.
Clotting Cascade: Creates a fibrin mesh to control bleeding and provide a framework for tissue repair.
Kinin System: Includes bradykinin, causing vasodilation and increased vascular permeability.

Acute Inflammation:
- Rapid onset; resolves within days (e.g., food poisoning).
Chronic Inflammation:
- Lasts beyond two weeks; can form scar tissue and lead to deformities (e.g., tuberculosis complications).
Consequences: Risk of granuloma formation when the immune response fails to eliminate pathogens effectively.

Healing involves reestablishment of tissue framework, scar formation begins within days, full maturation may take years.
Processes of Wound Healing:
- First Intention: Minimal tissue loss, faster healing with less scar formation.
- Second Intention: Significant tissue loss, prolonged healing, more scar tissue.
Factors Impeding Healing:
- Infection, poor nutrition, lack of oxygen, immunosuppressive therapies, poor blood flow.

Definition: Neoplasia refers to abnormal tissue growth that serves no physiological purpose.
Types of Tumors:
- Benign Tumors: Do not invade surrounding tissues; not cancerous.
- Malignant Tumors: Invasive, can metastasize, potentially lethal.
Oncology: Field devoted to cancer treatment and research, involving various specializations (e.g., radiation oncologist).

Mutation Accumulation: Requires 4-7 mutations for cancer development typically linked to age.
Carcinogenesis: Process involving initiation and promotion of cancer, associated with inherited and acquired mutations.
Carcinogens: Agents that may cause cancer, including chemicals and UV radiation.

Cancer rates are decreasing due to increased awareness and protective measures (e.g., sunscreen use).
Five-year survival rates improved to approximately 68% due to advancements in screening and treatment.
Common Cancers in Australia:
1. Breast Cancer
2. Colorectal Cancer
3. Prostate Cancer
4. Melanoma
5. Lung Cancer
Notable Age Groups for Common Cancers:
- Children: Blood cancers
- Middle Age: Breast, Prostate, Colorectal cancers
- Older Adults: Colorectal, Lung cancers

Inflammation is fundamental to understanding other disease processes.
Future lectures will expand on these concepts with more in-depth discussions and case studies.
End of Lecture: Introduction to further materials (videos and diagrams related to blood vessel changes during inflammation).