Describe organ agenesis
Absence of organ formation/development
Describe the sequence of hypoxic cell damage
1) Failure of oxidative phosphorylation
2) Depletion of ATP, increased ADP and AMP
3) Anaerobic glycolysis, glycogenolysis stimulated
4) Increased cell lactate, depletion of glycogen stores, decreased intracellular pH
5) Failure of Na/K ATP-pump > increased cell Na+/water and decreased K+
What type of necrosis occurs from pancreatic injury?
What components are needed to make soap? What is the process called?
Free fatty acids + calcium = soap = saponification
What type of necrosis is typified in TB?
Caseous necrosis occurs as part of what?
Irreversible condensation of chromatin
Destructive fragmentation of dying cell nucleus
Complete dissolution of chromatin of dying cells d/t DNAase
Karyolysis is usually found in what cellular pathology?
Pyknosis and karyorrhexis are usually found in what cellular pathology?
Necrosis or apoptosis
T/F: Swelling of the ER is reversible
What organ typically suffers from liquifactive necrosis?
List some cellular characteristics of coagulative necrosis
Eosinophilia (increased cellular proteins), loss of nuclei
Fatty liver is characterized by the cellular accumulation of what elements?
Intracellular parenchymal TGs
T/F: Fatty liver is reversible
In the advanced form, primary hemochromatosis is characterized by what pathologies?
'Bronze triad' = cirrhosis, diabetes, hyperpigmentation
Hemochromatosis is most often caused by a mutation in which gene?
Is hemochromatosis primarily spontaneous or familial in its etiology?
Deposits of hemosiderin (in hemochromatosis) can most often occur in which areas of the body?
Liver, pancreas, skin, joints, pituitary
In which pathology, dystrophic or metaplastic calcification, are serum calcium concentrations not elevated?
List some cellular injury formations which are reversible
Myelin figures, cell blebs, mitochondrial swelling, glycogen depletion
List some cellular injury formations which are not reversible
Pyknosis, karyorrhexis, karyolysis
What are the three types of cell growth types in the body? Give an example of each.
Labile (continually proliferate, e.g. blood cells)
Stable (low normal level of replication, e.g. mesenchymal cells)
Permanent (cannot divide in postnatal life, e.g. CNS neurons)
What are the two organs/systems that do not regenerate in postnatal life?
Cardiac myocytes, CNS neurons
In an organ, the regeneration of cells depends on what?
Parenchymatous tissue, whether or not the framework was destroyed
What are the best organs for regeneration?
T/F: Kidney and spleen are able to regenerate
Which cellular stage are stable cells considered to be halted in?
Stimulation of stable cells in G0 > G1 can occur via what mechanisms?
Growth of stimulatory factors
Loss of a growth inhibitor (negative feedback)
Cell-cell or cell-matrix interactions
List some well known growth substance classes and associated examples
Hormones (estrogen, progesterone, somatotropin)
Polypeptides (insulin, EGF, FGF, PGF, heme growth factor, IL-1, IL-2, TNF, nerve growth factors, macrophage derived growth factors)
Inhibitory factors for growth are also called what?
List the three best known chalone systems
Epidermal, granulocyte, lymphocyte
T/F: Chalones are tissue or cell line specific
Define contact inhibition
Cessation of cell growth/proliferation due to interaction with neighboring cell(s)
List some examples of integrins
Fibronectin receptor, platelet surface receptor, leukocyte adhesion markers
Cell receptors interacting with cell cytoskeletons are made of what?
What is arguably the most important ECM entity for healing?
Where are fibronectins seen?
Cell surfaces, basement membrane, pericellular matrices
What cells produce fibronectins?
FEM: Fibroblasts, endothelial cells, monocytes
When can cellular regeneration not occur?
Cellular injury severity includes damages parenchymal and stromal cells
Describe granulation tissue
Pink, soft, granular;
Mesh of capillaries, fibroblasts, inflammatory cells, ECM;
Bleeds freely, insensitive to pain, quite resistant to infections
List the steps of cellular repair
Maturation & organization of scar
What is the most common protein in the animal world?
Which types of collagen are fibrillary?
Types I, II, III
Which types of collagen are amorphous?
Types IV, V
Which enzymes degrade collagen?
List some cells which produce collagenase
Fibroblast, macrophage, PMN, synovial cells, some epithelial cells
List the components of the basement membrane
Types IV/V collagen, laminin, fibronectin, heparin sulfate proteoglycan
Which cells produce elastin?
T/F: Elastic fibers have a long half-life
What is the process of digesting elastin and which cell(s) are responsible for it?
Bacteria, PMN, macrophages
What is the function of laminin?
Mediates attachment of epithelial cells to Type IV collagen
T/F: Fibronectin is a glycoprotein
T/F: Fibronectin is a cryoglobulin
T/F: Most wounds involving skin, fascia or tendon never again regain initial strength or tissue derived
At 3 months of cellular healing, what percent of tensile strength has been recovered?
Adult skin has primarily what collagen type?
Granulation tissue has primarily what collagen type?
Cicatrization utilizes what collagen type(s)?
Replacement of Type III with Type I
List some example of repair sites typified by the cell repair mechanism
Repair of dermal wounds, ulcer, TB lung cavities, abcesses, trauma
List the general steps of wound repair
Crust formation >
Removal of dead tissue/debris/exudate >
Replacement of lost cells/tissue
What are the two general functions for the crust formation of wound healing?
Stops further blood leaking, barrier to infection
List two locations in which there is no crust formation?
Cornea, uterine mucosa
Describe the zone of demarcation
Dead tissue surrounded by inflammatory tissue
In wound repair, what are the mechanisms of inflammatory removal of tissue?
In wound healing, what cell types proliferate and migrate?
Fibroblasts, endothelium, epithelium
Why is wound regeneration in the cornea?
No defect in the underlying mesenchyme migration
Conversion of granulation tissue to scar
May form in repair following injury and inflammation of serous membranes (e.g. abdominal surgery)
Post-traumatic repair connective tissue proliferation in the dermis that exceeds 'above and beyond' repair.
Physically describe keloid
Gross: raised, firm lesion with sharp, irregular outline and smooth, shiny surface
Micro: epidermis/subajacent dermis are normal but no skin appendages, irregularly arranged, broad, homogenous, hyalinized and sometimes basophilic
Differentiate primary vs secondary repair/wound healing
Primary: repair when edges of wound are in apposition, no heavy scarring, e.g. cut w/ sharp object, regeneration, dermal cuts, sutures, abrasion
Secondary: considerable loss of tissue, edges of wound cannot be approximated, cicatrization more common, presence of granulation tissue
Wound separation by what distance usually requires skin grafting?
Define restitutio ad integrum
Full recovery, total healing
Which type of wound healing, primary or secondary, most mimics restitutio ad integrum?
What are the stages of wound closure?
Latent period (1-several days)
Period of contraction (edges pulled together)
Epidermalization (after contraction)
List some factors that influence the rate of healing
Age, size of wound, secondary infection, dietary status, immunity status, illness status
How can medicine influence healing?
Immobilize the injured area
Drainage of exudate and pus
Administration of abx in infections
Remove noxious materials
Control bleeding and remove excess clotted blood
Judicious use of suture material
Preserve blood supply
Elevation to help drain
Apply thermal modification
Maintain optimal nutrition status for given age
List some hormones which decrease the inflammatory response
Cortisone, hydrocortisone, corticosterone, ACTH
List some hormones which increase the inflammatory response
Deoxycorticosterone, pituitary somatotropic hormone
What mechanisms predispose diabetics to more severe reactions to infections
Tendency to vascular disease, metabolic imbalances, increased gluconeogenesis (ample nutrients), impaired Ab formation