Cell Injury and Adaptation in Pathology

Metaplasia

• A reversible change where one mature cell type is replaced by another mature cell type

Congestion

• Impaired venous drainage, leading to an accumulation of blood in the affected area

Irreversible Cell Injury

• Pyknosis: Nuclear shrinkage, increased basophilia, and chromatin clumping
• Karyorrhexis: Fragmentation of the pyknotic nucleus
• Karyolysis: Dissolution of the nucleus

Atropy

• A decrease in the size of a tissue or organ due to a decrease in the size of its individual cells
• Caused by factors like:
  • Severe protein-calorie malnutrition
  • Hypoxia

Apoptosis

• Programmed single-cell death, characterized by:
  • No rupture of the cell membrane
  • Absence of acute inflammation
  • Phagocytosis of apoptotic cells by neighbors
  • Formation of apoptotic bodies

Reversible Cell Injury

• ** Fatty change:** Accumulation of intracellular fat droplets
• Loss of microvilli: Indicates a decrease in cell surface area
• ER swelling: Indicates a disruption in cellular metabolism
• ** Cellular swelling:** Accumulation of water in the cell due to a disruption in cell membrane function

Thrombosis

• The occlusion or obstruction of a vessel by an abnormal mass (solid, liquid, or gaseous) transported from a different site by the circulation

Necrosis

• Types of necrosis include:
  • Caseous: Cheese-like appearance, commonly seen in tuberculosis
  • Coagulation: Denaturation of proteins, commonly seen in ischemic injury
  • Fibrinoid: Deposition of fibrin-like material in blood vessels
  • Fat: Necrosis of fat cells due to the release of lipases, commonly seen in pancreatitis

Chronic Inflammation

• Characterized by:
  • Fibrosis
  • Tissue destruction
  • Mononuclear cell infiltration
  • Angiogenesis
  • Unlike acute inflammation, edema is not a primary feature

Jaundice

• Caused by the accumulation of bilirubin in the blood and tissues

Complications of Wound Healing

• Keloid formation: An excessive scar formation
• Granulation tissue formation: A type of tissue that fills the wound
• Regeneration: Replacement of damaged tissue with similar tissue
• Inflammation: The initial phase of wound healing

Hematoma

• Subcutaneous collection of erythrocytes larger than 1 cm in diameter

Hemodynamic Disorders

• Disturbed perfusion that results in organ and cellular injury

Chemotaxis

• Movement of cells toward a certain site or source, often in response to chemical signals

Malignant Tumor

• Melanoma: A malignant tumor of melanocytes

Stable Cells

• Cells that have a limited capacity for division under normal conditions, including:
  • Heart muscle
  • Vascular endothelium

Histochemical Technique for Iron

• Prussian Blue: A stain that is used to identify iron deposits

Non-Tumor Lesions

• Hamarthoma: A benign tumor-like malformation composed of tissues normally found in the location of the growth

Hypoxic Injury

• Neurons: Are highly susceptible to hypoxic injury due to their high metabolic demand

Precancerous Lesion

• Dysplasia: Abnormal cell growth and development, which may progress to cancer

Main Fixative in Pathology

• Formaline: A commonly used fixative for tissue preservation

Multinucleated Giant Cells

• Macrophage: A type of white blood cell that can fuse to form multinucleated giant cells

Hemorrhage

• Presence of blood in the interstitial tissue outside of the blood vessels and heart

Features of Acute Inflammation

• Edema
• Unlike chronic inflammation, fibrosis and angiogenesis are not primary features.

Lipid Dissolution during Tissue Processing

• Alcohol: Is used to dissolve lipids during tissue processing

Most Common Cause of Cell Injury and Cell Death

• Hypoxia: A deficiency of oxygen

Most Common Malignant Tumor in Women

• Breast Cancer: The most common malignancy in women

Hallmark of Reversible Injury

• Cellular swelling: The first sign of reversible cell injury

Biopsy Technique for Cancer

• Incisional biopsy: A sample of the tumor is removed for examination
• Excisional biopsy: The entire tumor mass is removed for examination

Explore the concepts of cell injury, adaptation, and the underlying mechanisms involved in pathological conditions. This quiz covers key processes like metaplasia, apoptosis, and atrophy, providing insights into reversible and irreversible cell changes. Test your understanding of these critical cell biology topics.