Cell Injury, Death, and Adaptations Flashcards
Molecular Cause of Hypereosinophilia
Degradation of cellular protein and cytoplasmic RNA
What is aplasia?
failure in cell production during fetal development or later by loss of precursor cells in proliferative tissue
Cell types unable to undergo hyperplasia
Cells that are incapable of mitotic division:
- Skeletal muscle
- Cardiac muscle
- Neurons
- Glomeruli
- Retinal epithelium
Cause (and tissue type) of thicking of uterus during normal cycle
Hyperplasia of the endometrial glands and stroma
(+) Estrogen
(-) Progesterone
Cause (and tissue type) of thicking of uterus during pregnancy
Hyperplasia of smooth muscle
(+) Estrogen
(-) Progesterone
Cause (and tissue type) of breast growth during puberty/pregnancy
hyperplasia of glandular epithelium
In cardiac m hypertrophy, what are the vasoactive compounds and growth factors that initiates gene activation?
Vasoactive compounds:
- Angiotensin II
- Endothelin
Growth factors:
- TGF-ß
- Insulin-like GF
What are the structural/molecular changes that accompany cardiac hypertrophy?
- change from a to fetal ß-myosin
- decreases ATPase
slower, energy-efficient contraction
- Change to fetal ANF
- increases Na excretion, with water, to decrease blood volume and pressure
What is Cachexia? What causes it? MOA?
Muscle wasting
Causes: Marasmus, chronic inflammation
Overproduction of TNF suppresses appetite and induces muscle atrophy
Mechanisms of protein degradation associated with atrophy
- Lysosomal enzymes
- Ubiquitin-proteasome pathway
What is shown in the picture? What does it signal?
Lipochrome pigment: autophagic granules signify atrophy
Also: lipofuscin pigments
What type of cellular process is shown? What is this condition called? What type of transformation? Cause?
Metaplasia
Barrett’s esophagus
In the esophagus: squamous to columnar (secreting) epithelium
Result of acid reflux disease
What type of cellular process is shown? What is this condition called? What type of transformation? Cause?
Metaplasia
Laryngeal metaplasia
Respiratory epithelium (columnar) to squamous
Smoking
What type of cellular process is shown? Characteristics?
Dysplasia of squamous epithelium of cervix
Hyperchromatic nuclei and mitotic spindles: Mitosis occurs at all tissue levels
Loss of cell polarity
Damage to cell following ischemia
Damage to mitochondria following increased Ca lvls, ROS damage, or lipid peroxidation
Cell damage following loss of Ca homeostasis
ROIs formed from radiation
Hydrolyzes water to hydroxyl and hydrogen free radicals
Metabolism of Superoxide
SOD and forms H2O2
Metabolism of H2O2
- Catalase: H20
- Glutathione peroxidase: Hydroxide + Hydroxy-radical
- Fenton reaction with iron or copper: Hydroxide + Hydroxy-radical
Significance of Malondialdehyde in blood or urine
oxidative damage (due to lipid peroxide radical formation)
Characteristics of necrotic cells
- cytoplasmic eosinophilia (degradation of cytoplasmic RNA and denaturation of proteins)
- Karyolysis, Pyknosis, and Karyorrhexis
**causes inflammation from leakage of cytoplasmic contents
Characteristics of Coagulative necrosis
- Results from hypoxic death (of all tissues except the brain)
- Denaturation of proteins (from low ATP -> anaerobic -> increased lactic acid) which results in preservation of outline of dead cells
- firm texture
- wedge-shape
Characteristics and causes of liquifactive necrosis
Causes:
- brain hypoxia (microglia)
- Abcess (neutrophils)
- Pancreatitis (proteases)
- Bacterial/fungal infection
Characteristics:
- viscous liquid mass (enzymatic digestion)
- focal accumulation of inflammatory cells