2P07 Class 2

What is defined as reversible changes in cell size, number, phenotype, metabolic activity, and functions?

Cellular adaptation

True or False: A cell must be injured or damaged to undergo cellular adaptation.

FALSE

Term: Atrophy

Definition: The shrinkage in cellular size.

Under what condition does physiological atrophy typically occur?

During early development.

Which type of atrophy results from decreases in workload, pressure, or blood supply?

Pathological atrophy

Term: Hypertrophy

Definition: An increase in cellular size.

How does physical hypertrophy differ from pathological hypertrophy regarding structure and function?

Physical hypertrophy maintains structure and function, while pathological hypertrophy does not necessarily maintain them.

What is defined as an increase in the number of cells resulting from an increased rate of cellular division?

Hyperplasia

Which type of hyperplasia serves as an adaptive mechanism enabling certain organs to regenerate?

Compensatory hyperplasia

In which organs does hormonal hyperplasia mainly occur?

Estrogen-dependent organs such as the uterus and breast.

The abnormal proliferation of normal cells is known as _____ hyperplasia.

Pathological

Term: Terminal Differentiation

Definition: The state where cells will never divide again once they have matured postnatally.

What is the reversible replacement of one mature cell type by a different, less differentiated cell type?

Metaplasia

Metaplasia in the bronchial lining replaces normal columnar ciliated epithelial cells with cells that lack _____.

Cilia (or mucus secretion)

Why is bronchial metaplasia considered a loss of a vital protective mechanism?

The new cells do not have cilia and do not secrete mucus.

Term: Dysplasia

Definition: Abnormal changes in the size, shape, and organization of mature cells.

True or False: Dysplasia is considered a true adaptive change.

FALSE

Under what condition can metaplasia and dysplasia be reversed?

If the irritating stimulus is removed.

What is the biological response to cell injury caused by pathogens, irritants, or chronic conditions?

Inflammation

Regarding the relationship between inflammation and infection, which one cannot be caused by the other?

An infection cannot be caused by inflammation.

What are the four cardinal signs of inflammation in Latin?

Rubor, Calor, Tumor, and Dolor.

In the context of inflammation, what does the term 'Rubor' signify?

Redness

In the context of inflammation, what does the term 'Calor' signify?

Heat

In the context of inflammation, what does the term 'Tumor' signify?

Swelling

In the context of inflammation, what does the term 'Dolor' signify?

Pain

What is the very first step of the vascular response in acute inflammation?

Momentary vasoconstriction

Which system causes the initial vasoconstriction during the inflammatory vascular response?

The Sympathetic Nervous System

During the vascular response, what mediator (chemical substance that controls how blood vessels behave during inflammation, injury etc.) release leads to vasodilation and increased vascular permeability?

Histamine

What is the process of bringing white blood cells to the site of inflammation via signaling factors?

Chemotaxis

The movement of cells from the capillaries to the site of injury is called _____.

Diapedesis

What are the two primary causes for the slowing of blood flow during inflammation?

Increased blood viscosity and increased lumen diameter.

Which white blood cells are the first to arrive at the injury site to phagocytize bacteria?

Neutrophils

Which cells phagocytize inflammatory debris and can transform into multinucleated giant cells or granulomas?

Macrophages

Monocytes are phagocytic cells that eventually turn into _____.

Macrophages

Which specific white blood cell type shows a strong response during allergic reactions?

Eosinophils

What two substances are released by basophils during the inflammatory response?

Histamine and Heparin.

Where is histamine primarily stored in the body?

Granules of basophils, mast cells, and platelets.

How does histamine increase vascular permeability?

By stimulating contraction of endothelial cells to create widened gaps between them.

Besides platelets and mast cells, where else is serotonin stored in the body?

Enterochromaffin cells of the gastrointestinal tract.

From which precursor factor (substance that comes before another and leads to its formation) are kinins (short lived biologically active peptide hormones), such as bradykinin, produced?

Kininogen

Activation of which clotting factor leads to the production of kinins?

Hageman factor ($XII$)

What are the anaphylatoxic agents generated from the complement pathway?

$C3a$, $C4a$, and $C5a$.

Which inflammatory mediators are produced from membrane phospholipids and converted by the enzyme lipoxygenase?

Leukotrienes

Which enzyme converts arachidonic acid into prostaglandins?

Cyclo-oxygenase (COX)

Which form of the COX enzyme is found in most tissues and performs a general protective function?

COX-1

Which form of the COX enzyme is specifically associated with the inflammatory response?

COX-2

Which specific prostaglandin (lipid compounds part of inflammation) is identified as a strong pyrogen (fever causing substances)?

PGE2

Term: Cytokines

Definition: Signaling molecules with specific membrane receptors that regulate innate or adaptive immune systems.

What is an example of serous inflammatory exudate?

Skin blisters (or pleural effusion).

A runny nose associated with an upper respiratory infection is an example of _____ exudate.

Catarrhal

What type of exudate is characterized by the presence of adhesions (scar-like tissue where fibrous exudate acts as a sticky net between internal surfaces)

Fibrinous exudate

Purulent exudate is more commonly known as _____.

Pus

What is an example of hemorrhagic inflammatory exudate?

Hematoma (localized collection of pooled, mostly clotted blood outside of damaged blood vessels)

The systemic increase in the number of circulating white blood cells is called _____.

Leukocytosis

Which organ is responsible for the increased synthesis of plasma proteins during acute inflammation?

The liver

On which part of the brain do pyrogens act directly to induce fever?

The hypothalamus

Which three specific cytokines are released by monocytes/macrophages to trigger the febrile response (rise in body temperature due to blood product transfusion)?

$IL-1$, $IL-6$, and $TNF$.

How does the autonomic nervous system decrease heat loss during the onset of fever?

By decreasing perspiration (sweat) and blood flow to the periphery.

Which hormone is released from the adrenal medulla as part of the febrile response? (rise in temperature during blood product transfusion)

Epinephrine

The abnormal changes in organization of mature cells that is often a precursor to cancer is _____.

Dysplasia

Which inflammatory mediator is involved in both the vascular response (vasodilation) and the pain response?

Histamine (or Kinins/Serotonin)

What adaptive mechanism enables the liver to regenerate after partial resection?

Compensatory hyperplasia

According to the pathophysiology map, what two types of responses follow cell injury?

Vascular response and cellular response.

Which cytokine inhibits cytokine production to help limit inflammation?

$$IL-10$$

Which factor is responsible for activating macrophages during the repair and healing phase?

$$IFN-\gamma$$

What type of inflammation is characterized by diffuse inflammation in connective tissue?

Cellulitis

Which inflammatory mediator stimulates smooth muscle contraction and is a neurotransmitter involved in pain?

Serotonin

What is the result of arachidonic acid being converted by the enzyme lipoxygenase?

Leukotrienes

Which specific leukotriene is noted for stimulating chemotaxis?

Leukotriene $B_4$

Inflammatory exudate is composed of fluid and _____ that move from circulation to the injury site.

Leukocytes

What are the 4 particular properties of an acute inflammatory process

1. vascularized

2. rapid onset

3. dependent on the activity of both cellular and chemical components

4. nonspecific

Role of histamine in acute inflammatory process (vascular response)

allows fluid (like proteins and WBC) to pass through veins

which cell is related to the immune response

lymphocytes

which cell is phagocytic that turn into macrophages

monocytes

which cell releases histamine and heparin

basophils

explain the process of causing a fever involving prostaglandins

• arachidonic acid is converted into prostaglandins by the enzyme cyclo-oxygenase

• this then goes to the hypothalamus to cause a fever

• fever causes temperature to rise, so bacteria die

Stages of the febrile response - Nonspecific reports such as mild headache, fatigue, general malaise, muscle aches

prodrome (an early sign, symptom, or set of symptoms that indicates the impending onset of a disease)

Stages of the febrile response - Cutaneous vasoconstriction, “goose pimples,” pale skin; feeling of being cold; generalized, shaking chill; shivering that causes body to reach new temperature set by control centre in hypothalamus

chill

stages of the febrile response - Sensation of warmth throughout body; cutaneous vasodilation; warming and flushing of skin

flush

stages of the febrile response - Sweating (diaphoresis); decrease in body temperature

defervescence

What is the skin condition (intact/non-intact) for a Deep Tissue Pressure Injury?

Skin may be intact or non-intact.

What color changes indicate a Deep Tissue Pressure Injury?

Non-blanchable deep red, maroon, or purple discoloration, a dark wound bed, or a blood-filled blister.

What subtle signs often occur before skin color changes in a Deep Tissue Pressure Injury?

Pain and temperature changes.

What is the typical progression or outcome of a Deep Tissue Pressure Injury?

It may resolve without tissue loss or quickly deteriorate into a deeper injury.

What is the skin condition for a Stage 1 pressure injury?

Intact skin with non-blanchable (does not turn white when you press it) erythema

How does a Stage 1 pressure injury present on dark skin versus light skin?

• Dark skin: Appears purple, blue, or a darker hue compared to surrounding skin.

• Light skin: Redness that does not include purple or maroon discoloration.

What early changes may precede visible skin changes in Stage 1?

Changes in sensation, temperature, or firmness.

What depth of tissue loss occurs in a Stage 2 pressure injury?

Partial-thickness skin loss with exposed dermis.

Is adipose (fat) tissue visible in Stage 2?

No. Adipose tissue and deeper structures are not exposed.

Are granulation tissue, slough, or eschar present in Stage 2?

No. Granulation tissue, slough, and eschar are absent in Stage 2.

What is the healing potential for Stage 2 pressure injuries?

With appropriate nursing support and pressure offloading, the wound bed can heal.

What depth of tissue loss defines a Stage 3 pressure injury?

Full-thickness skin loss with exposed adipose (fat) tissue.

What tissue types are often present in a Stage 3 wound bed?

Granulation tissue is often present, along with possible slough or eschar.

Are fascia, muscle, tendon, ligament, cartilage, or bone exposed in Stage 3?

No. Deeper structures like fascia, muscle, tendon, ligament, cartilage, and bone are not exposed.

What wound complications or extensions are common in Stage 3?

Undermining and tunneling (or a combination of both).

What defines a Stage 4 pressure injury?

Full-thickness skin and tissue loss with exposed fascia, muscle, tendons, ligaments, cartilage, or bone.

What tissue types or extensions are commonly seen in Stage 4?

• Slough or eschar may be present, and undermining and/or tunneling are common.

• Slough is a pale yellow, white, cream, or tan layer of dead tissue and protein buildup that forms in an acute or chronic wound bed

• eschar - thick, dry, and leathery layer of dead tissue that forms over a severe wound

Why is a pressure injury classified as "Unstageable"?

The full depth of tissue destruction cannot be visualized because it is covered by slough or eschar.

What is slough and what does it look like?

Slough consists of dead cells and fibrin. It is typically moist and yellow or white in appearance.

How does slough affect wound healing?

It impedes healing until removed.