Cell Structure & Epidemics Overview

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Questions and Answers

What primarily differentiates an epidemic from a pandemic?

An epidemic occurs when a new strain is discovered.

An epidemic is a sudden increase in cases in large cities.

A pandemic is always caused by a change in the environment.

A pandemic specifically affects multiple countries or continents. (correct)

Which structure in the cell is responsible for regulating substance movement?

Mitochondria

Cell membrane (correct)

Nucleus

Cytoplasm

During which phase does a cell actually duplicate its DNA?

S (Synthesis) (correct)

M (Mitosis)

G-2

G-1

What is the main function of cell differentiation?

To ensure specialized functions are performed for survival. Signup and view all the answers

Which phase of the cell cycle is characterized by the cell's everyday activities?

G-0 (resting stage) Signup and view all the answers

What is the ultimate result of mitosis in the cell cycle?

Two identical daughter cells are formed. Signup and view all the answers

What is the primary result of cellular proliferation?

The ability to repair and replace tissues. Signup and view all the answers

How do stem cells contribute to cell differentiation?

They receive signals directing them to differentiate. Signup and view all the answers

What is the primary goal of chemotherapy in treating cancer?

To eliminate as many cancer cells as possible Signup and view all the answers

Which phase of the cell cycle is characterized by cell growth and preparation for DNA replication?

G-1 phase Signup and view all the answers

What is the significance of debulking a tumor before chemotherapy?

It makes remaining cells enter active phases of mitosis Signup and view all the answers

Which category of antineoplastic agents interrupts the S-phase of the cell cycle?

Antimetabolites Signup and view all the answers

Which type of cell is capable of dividing under stress or injury conditions?

Stable cells Signup and view all the answers

Why are non-cycle specific drugs like alkylating agents effective at any stage of the cell cycle?

They work on the DNA regardless of cell cycle phase Signup and view all the answers

What type of tissue is specialized for contraction and movement?

Muscular tissue Signup and view all the answers

Which type of cells are considered permanent and do not have regenerative capability?

Cardiac cells Signup and view all the answers

What is the focus of palliative chemotherapy?

Enhancing the patient's overall quality of life Signup and view all the answers

In what way do chemotherapeutic drugs exhibit reduced effectiveness?

In the resting phase (G-0) Signup and view all the answers

Which term describes the increase in cell size due to increased demand?

Hypertrophy Signup and view all the answers

What stage follows the S-phase in the cell cycle?

G-2 phase Signup and view all the answers

What is cellular adaptation primarily focused on maintaining?

Homeostasis Signup and view all the answers

What is a consequence of atrophy in cells?

Decrease in cell size Signup and view all the answers

When do adaptive responses in cells generally cease?

When the stressful stimulus is removed Signup and view all the answers

Which of the following is NOT a basic type of tissue?

Endothelial Signup and view all the answers

Which side effect is specifically associated with radiation treatment?

Radiodermatitis Signup and view all the answers

What is a common risk associated with chemotherapy?

Risk of infection Signup and view all the answers

What does 'cross-resistance' refer to in cancer treatment?

Resistance to multiple drugs simultaneously Signup and view all the answers

Which precaution is NOT recommended for handling cytotoxic drugs?

Using a face shield Signup and view all the answers

What should be done with cytotoxic waste after drug administration?

Dispose of in designated hazardous waste containers Signup and view all the answers

Which of the following is NOT a potential side effect of chemotherapy?

Radiodermatitis Signup and view all the answers

Which is a mechanism by which cancer cells develop resistance to chemotherapy?

Enhanced regenerative enzyme production Signup and view all the answers

What is the appropriate action after handling cytotoxic drugs?

Wash hands thoroughly Signup and view all the answers

What is a potential long-term effect of chemotherapy on children?

Cardiomyopathy Signup and view all the answers

Which of the following may be a concern for children who receive radiation therapy?

Infertility Signup and view all the answers

What should be emphasized by nurses when dealing with children undergoing cancer treatment?

Positive relationships with staff Signup and view all the answers

What is a possible psychological effect that cancer survivors may face?

Higher rates of depression Signup and view all the answers

Which outcome is related to head and neck radiation?

Impaired growth of bones and teeth Signup and view all the answers

In terms of cancer screening, which group of adults benefits most from being screened?

Adults with a life expectancy of over 10 years Signup and view all the answers

What is a potential long-term effect of chemotherapy related to vision?

Cataracts and other eye problems Signup and view all the answers

What aspect should parents focus on when making decisions about their child's cancer treatment?

Gathering resources to support the child Signup and view all the answers

Which condition is diagnosed when platelet count drops below 100,000 per milliliter of blood?

Thrombocytopenia Signup and view all the answers

What adverse effect is most likely to result from chemotherapy due to the sensitivity of tissues with high growth fractions?

Severe mucositis and gastrointestinal impacts Signup and view all the answers

Which drug is known for potentially causing the most severe tissue damage when accidentally infiltrated into surrounding tissue?

Vesicants Signup and view all the answers

What is the primary nursing consideration for managing patients receiving chemotherapy?

Monitoring for signs of extravasation Signup and view all the answers

Which medication may be administered to stimulate red blood cell production in cancer patients experiencing anemia?

Epoetin alfa Signup and view all the answers

What primarily causes cellular hypertrophy?

Increased demand for contractile proteins Signup and view all the answers

What is a defining characteristic of hyperplasia?

Increase in the number of cells Signup and view all the answers

What occurs during metaplasia?

Reversible replacement of one mature cell type by another Signup and view all the answers

What might lead to muscle atrophy?

Extended period of immobilization Signup and view all the answers

Which factor does NOT commonly contribute to cellular adaptation?

Increased oxygen availability Signup and view all the answers

Which of the following best describes 'plasia' in a cellular context?

Cell formation or growth Signup and view all the answers

What could be a potential pathological example of hyperplasia?

Enlarged prostate in benign prostatic hyperplasia Signup and view all the answers

What is the primary process by which a cell undergoes programmed cell death?

Apoptosis Signup and view all the answers

What is the primary consequence of oxidative stress on healthy cells?

DNA damage Signup and view all the answers

Which condition leads to hydropic degeneration in cells?

Impairment of the sodium-potassium-ATPase pump Signup and view all the answers

What role do antioxidants play in cellular regulation?

They regulate cell function and immune response. Signup and view all the answers

What is a physiological role of apoptosis during embryonic development?

Separation of webbed fingers and toes Signup and view all the answers

What outcome results from severe cell damage that does not lead to apoptosis?

Necrosis Signup and view all the answers

Which of the following is NOT a source of endogenous free radicals?

Cigarette smoke Signup and view all the answers

What condition can lead to hypoxic cell injury?

Cessation of blood flow Signup and view all the answers

Which factor is NOT associated with reversible cellular injury?

Programmed cell death Signup and view all the answers

What cellular process is characterized by the accumulation of fat due to impaired metabolism?

Fatty changes Signup and view all the answers

Which of the following is a cause of cell injury due to genetic defects?

Misfolded proteins Signup and view all the answers

Which statement is true regarding the inflammatory process in apoptosis?

Apoptosis does not activate any inflammatory processes Signup and view all the answers

What impact does high blood sugar have on the body with respect to oxidative stress?

Increases oxidative stress on blood vessels Signup and view all the answers

Which vitamin is considered an important antioxidant to combat free radicals?

Vitamin C Signup and view all the answers

What is the effect of oxygen deprivation on the brain and heart's red blood cells?

Decreased life span Signup and view all the answers

What mechanism allows for the control of immune cell population?

Apoptosis Signup and view all the answers

What is one of the consequences of the accumulation of damaged nucleic acids in cells?

Triggering of cell death Signup and view all the answers

Which process occurs when ATP production resumes after an injury?

Reversal of hydropic changes Signup and view all the answers

Which of the following best describes Reactive Oxygen Species (ROS)?

Highly reactive free radicals containing oxygen Signup and view all the answers

What metabolic issue can result from insufficient oxygen supply?

Inhibited metabolic processes Signup and view all the answers

What is a primary benefit of combination therapy in cancer treatment?

Targets different tumor clones Signup and view all the answers

Which of the following side effects is specifically linked to bone marrow suppression due to chemotherapy?

Anemia Signup and view all the answers

Which cell type is most sensitive to chemotherapy due to its short lifespan?

Neutrophils Signup and view all the answers

What is a common risk associated with the treatment of cancer that involves chemotherapy?

Drug resistance Signup and view all the answers

Which of the following is a potential consequence of low neutrophil counts in patients undergoing chemotherapy?

Increased risk of infections Signup and view all the answers

In the context of hematologic considerations, what is the main purpose of colony-stimulating factors like filgrastim?

Boost white blood cell count Signup and view all the answers

What characterizes the antineoplastic agents used in breast cancer protocols?

Target multiple stages of cancer cell life cycle Signup and view all the answers

Which of the following side effects indicates organ toxicity as a risk during chemotherapy?

Cytotoxicity Signup and view all the answers

What is the role of using lower dosages of multiple drugs in chemotherapy?

To lower toxicity while increasing efficacy Signup and view all the answers

Which complication can arise from extravasation during chemotherapy?

Localized tissue damage Signup and view all the answers

Study Notes

Epidemics vs. Pandemics

Epidemic: A sudden increase in the number of cases of a disease in a specific region or population.
Causes: New pathogen strains, environmental changes, or inadequate vaccination coverage.
Pandemic: A disease that has spread across countries or continents, affecting a large global population.
Key characteristics: Often involves a new pathogen that most people have little immunity against.

Cell Structure & Function

The cell is the smallest functional living unit, with over 30 trillion cells in the human body.
Three main parts:
- Cell membrane: Encloses the cell and regulates the movement of substances in and out.
- Nucleus: Houses the majority of the cell's DNA (genetic material).
- Cytoplasm: A gel-like fluid inside the cell containing various cell components with specific functions, excluding the nucleus.

The Cell Cycle

G-0 (Resting stage): Cell performs its everyday activities specific to its type (metabolism, contraction, etc.). Cells spend most of their lives in this phase.
G-1 (Growth Stage): First step after receiving the signal to divide; the cell synthesizes RNA, proteins, and components needed for DNA duplication.
S (Synthesis): Cell duplicates its DNA.
G-2 (Pre-mitotic phase): Cell produces additional proteins and components necessary for cell division (mitosis).
M (Mitosis): Cell undergoes mitosis (prophase, metaphase, anaphase, telophase), resulting in the splitting of one cell into two identical daughter cells.

Cell Proliferation & Cell Differentiation

Cell proliferation: Cells multiply through mitosis, allowing the body to grow, repair, and replace cells. This process is tightly regulated to ensure cells divide only when necessary.
Cell differentiation: The process by which a cell becomes more specialized with distinct functions, ensuring cells can perform specific functions needed for an organism's survival.
Stem cells: Special cells with the ability to develop into various cell types. They receive signals during differentiation, guiding them to become a specific type of cell.
Stem cell research: Explores the potential to repair and regenerate damaged tissues and organs through controlled stem cell differentiation. This opens up potential therapies for conditions like Parkinson's disease, heart disease, and spinal cord injuries.

Cell Types: Labile, Stable, & Permanent

Labile cells: Constantly dividing and replacing lost cells. Examples include skin cells and intestinal epithelial cells.
Stable cells: Don't divide under normal conditions but can be stimulated to divide after injury. Examples include hepatocytes (liver cells) and liver regeneration.
Permanent cells: Lack regenerative ability. Examples include cardiac, neural, and skeletal cells. This lack of regeneration contributes to reduced cardiac capacity after a heart attack.

Tissues: Four Basic Types

Epithelial tissue: Lines all internal and external surfaces of the body.
Muscular tissue: Specialized for contraction, enabling movement and force generation in the body.
Connective tissue: Supports, connects, or separates different tissues and organs.
Nervous tissue: Specialized for transmitting electrical impulses to coordinate bodily functions, facilitating communication between body parts.

Cellular Adaptation: Atrophy & Hypertrophy

Cellular adaptation: A cell's ability to adjust to stimuli and challenging environmental conditions that threaten its structure or function.
Stimuli: Can be physiological (e.g., breast development during pregnancy) or pathological (e.g., aging)
Atrophy: Decrease in cell size, leading to degeneration of tissue.
- Occurs due to a reduction in cell content, resulting in lower oxygen consumption.
- Example: Muscle atrophy from disuse.
Hypertrophy: Enlargement of cells, increasing in size and functional components.
- Cells adapt to work demands or threats to survival by changing in size.
- Example: Bigger muscles have more ATP, actin, and myosin filaments.

Chemotherapy: Antineoplastic Pharmacotherapy

Goal of antineoplastic pharmacotherapy: To kill the majority of cancer cells and allow the immune system to complete the process.
Challenge: Targeting only neoplastic cells without harming healthy cells.
Three main approaches:
- Cure: Targeting small, localized tumors for greater chances of success.
- Control: Preventing tumor growth and spread to extend the client's life.
- Palliation: Shrinking a tumor to alleviate pain and symptoms, improving the patient's quality of life.

The Cell Cycle and Antineoplastics

Chemotherapy drugs are less effective on cells in the resting phase (G-0).
Debulking a tumor (surgically removing part) can enhance the efficacy of chemotherapy drugs by forcing remaining cells into active phases of mitosis where they are more vulnerable.

Antineoplastic Agents: Cycle-Specific and Non-Cycle-Specific

Cycle-specific drugs: Target specific phases of the cell cycle.
Non-cycle-specific drugs: Can kill cancer cells at any stage of the cell cycle.
Alkylating drugs: Non-cycle specific, target DNA formation and repair. Example: Nitrogen mustards and cyclophosphamide.
Anti-metabolites: Interrupt the S-phase (DNA synthesis) of the cell cycle.

Cancer Treatment Modalities: Surgery, Radiation, & Chemotherapy

Surgery: Used to remove tumors.
Radiation therapy: Delivers high-energy radiation to kill cancer cells.
Chemotherapy: Uses drugs to kill cancer cells.

Side Effects of Cancer Treatment

Common side effects: Pain, inflammation, anemia, bone marrow suppression, fatigue/malaise, nausea/vomiting, alopecia (hair loss), risk of infection, hematomas (bruising), hemorrhage, radiodermatitis (inflammation of skin from radiation), risk of atelectasis (lung collapse), pneumonia, hypoxia (low oxygen levels), risk of DVT (deep vein thrombosis), and extravasation (drug leaking out of blood vessels).

Cancer Cell Resistance: Mechanisms & Approaches

Primary resistance: Cancer cells are inherently resistant to a particular drug.
Acquired resistance: Cancer cells develop resistance to a drug after initial treatment.
Mechanisms of resistance:
- Reduced drug uptake
- Enhanced regenerative enzyme production (repairing DNA)
- Altered enzymatic function
- Deactivation of the drug
Cross-resistance: Resistance to one drug can lead to resistance to other chemically similar drugs.
Multi-drug/treatment approach: Using a combination of drugs aims to enhance efficacy and decrease resistance.

Nursing Considerations: Cytotoxic Precautions

Cytotoxic substances: Damage or kill cells and tissues.
Nurses must follow safety measures: Minimize their exposure to cytotoxic drugs and waste (urine, feces, vomit).
Chemotherapy can remain in the body for 3-7 days.
Personal Protective Equipment (PPE): Gloves, gowns, mask, and eye protection as needed.
Safe administration: Use infusion pumps and equipment to prevent spills or leaks.
Environmental cleaning: Thorough cleaning of surfaces and equipment after drug administration using appropriate cleaning agents.
Spill management: Follow protocols for containment, cleanup of any drug spills, and emergency procedures for accidental exposure.
Cytotoxic waste disposal: Dispose of cytotoxic waste in designated hazardous waste containers, following institutional and regulatory guidelines.
Hand hygiene: Wash hands thoroughly after handling cytotoxic drugs or potentially contaminated materials.
Pregnant women: Not allowed to handle cytotoxic drugs.

Lifespan Considerations: Children & Adolescents

Developmental stage influences reaction to illness.
Positive relationships with staff are important.
Long-term effects of chemotherapy:
- Cardiomyopathy
- Hearing loss
- Cataracts and other eye problems
- Learning disabilities
- Infertility
Long-term effects of radiation:
- Impaired growth of bones and teeth
- Hypothyroidism (from head and neck radiation)
- Delayed puberty and sterility
- Impaired neurocognitive performance
Cancer treatment can predispose to secondary cancers.
Survivors may have higher rates of depression and suicidal ideation.
Nurses can emphasize hope and purpose in life for survivors.
Parents: Make treatment decisions, gather resources to support their child, and adjust their lives to integrate the needs of their child with cancer.

Lifespan Considerations: Pregnant Women

Some cancers can spread to the placenta; most cannot spread to the fetus.
Delayed diagnosis may occur in pregnant women.
Screenings for specific cancers are recommended.

Lifespan Considerations: Older Adults

Risks and benefits of cancer screening must be considered.
Screenings for specific cancers are recommended for adults with a life expectancy greater than 10 years.

Cellular Adaptation

Cells adapt to work demands or threats to survival by changing in size (hypertrophy) or number (hyperplasia).

Hypertrophy

Increase in cell size.
Caused by increased functional demands or specific hormonal stimuli.
Examples:
- Exercise and muscle mass (physiological)
- Uterus enlargement during pregnancy (physiological)
- Myocardial hypertrophy from hypertension (pathological)

Hyperplasia

Controlled increase in the number of cells in an organ or tissue.
Occurs in wound healing with proliferating fibroblasts of connective tissues.
May occur together with hypertrophy.
Examples:
- Uterus
- Stimulation of the endometrium in the follicular stage of the menstrual cycle (physiological).
- Benign Prostate Hyperplasia (pathological)
- Endometrial hyperplasia (pathological)

Metaplasia

Reversible replacement of a mature, differentiated cell type by another cell type that is better suited to tolerate a particular stimuli or environment.
Example: Single dancer looking to pair up.

Oxidative Stress

Occurs when the production of free radicals exceeds the ability of the body to neutralize it.
Free radicals are highly reactive with molecules in their vicinity and can convert other molecules into additional free radicals.
Sources:
- Endogenous: from cell metabolic processes (e.g., ATP production), inflammation.
- Exogenous: Cigarette smoke, UV from sun rays.
Can damage proteins, lipids, and carbohydrates in cells/tissues, causing membranes damage, inactivation of enzymes, and damage to nucleic acids that make up DNA.
Antioxidants: Vitamins A, C, E, zinc, Beta-carotene, etc.

Genetic Defects

Cause cell injury due to a deficiency in functional proteins or the accumulation of damaged DNA or misfolded proteins.
Trigger cell death when they are beyond repair.
Examples: Sickle cell anemia (caused by a single amino acid substitution in hemoglobin).

Hypoxic Cell Injury

Oxygen deficiency related to a lack of oxygen in the air, respiratory disease, anemia, ischemia (restriction in blood flow), etc.
Deprives the cell of oxygen, interrupting the generation of ATP and other metabolic processes.
Brain and heart are sensitive to oxygen deprivation.

Outcomes of Cell Injury

Reversible cellular damage
Apoptosis (programmed cell removal)
Cell death (necrosis)

Reversible Cell Injury

Cellular Swelling: Impairment of the sodium-potassium-ATPase pump leads to accumulation of Na and water inside the cell. Hydropic degeneration.
Fatty changes: Intracellular accumulation of fat, causing small vacuoles of fat to disperse throughout the cell. Accumulation related to:
- Increased fat load (Obesity)
- Impairment of fat metabolism

Cell Death

Programmed Cell Death (Apoptosis): Highly selective process that controls tissue regeneration by eliminating injured and aged cells. Cellular suicide.
Responsible for several physiological processes:
- Programmed destruction of cells during embryonic development (e.g., separation of webbed fingers and toes).
- Hormone-dependent involution of tissue (e.g., endometrial cells during the menstrual cycle, regression of breast tissue after breastfeeding).
- Control of immune cells.

Cancer Treatment Protocols

Describe the specific combination of antineoplastics, their doses, and cycles of administration.
Each cancer type has a unique protocol developed through clinical trials.

Benefits of Combination Therapy

Target Multiple Stages of the cancer cells life cycle.
Attack Different Tumor Clones through various mechanisms.
Increase Efficacy of cancer cell kill.
Lower Dosages of each drug to reduce toxicity.
Slow the development of drug resistance.

Examples of Treatment Protocols

Breast Cancer: Cyclophosphamide, Methotrexate, Fluorouracil.
Lung Cancer: Cyclophosphamide, Doxorubicin, Vincristine.