Review Questions Flashcards
Which cells do not divide regularly, but can be stimulated to divide (can enter cell cycle if needed) and are located in parenchymal (solid) organs such as the liver and kidneys.
Quiescent Cells/Stable Cells
What are the 4 most important cells involved in wound healing?
- Leukocytes
- Macrophages
- Connective Tissue Cells
- Epithelial cells
(PMN’s play a brief scavenging role, then macrophages stay)
Which 3 cells participate in wound healing?
- Myofibroblasts
- Angioblasts
- Fibroblasts
Which cell in wound healing?
- Hybrid properties of both smooth muscle cells and Fibroblasts
- They contract within first few days of healing (reducing defect)
- Holds margins of tissue in close approximation
Myofibrobasts
Which cell in wound healing?
- Precursors of blood vessels that proliferate like sprouts from several small blood vessels at margins of wound
- Appear 2 - 3 days after incision
- By 5th - 6th day newy formed blood vessels are all over the field (allows for influx of blood w/ O2 and nutrients)
Angioblasts
Which cell in wound healing?
- Produce most of the extracellular matrix:
- Fibronectin- tensile strength to connective tissue matrix and glues other substances and cells together
- Collagen- wound initially w/ type 3 collagen (immature/young) laid by fibroblasts
Fibroblasts
- Necrotic tissue attracts Calcium Salts and frequently undergoes calcification
- Macroscopic deposition of calcium in injured/dead tissues
- Visible to naked eye
- Gritty/sand-like grains to firm, rock hard material
Dystrophic Calcification
- Calcifications in atherosclerotic coronary arteries (contributes to narrowing of vessels)
- Calcifications of mitral or aortic valves (leads to impeded blood flow/stenosis)
- **Calcifications seen around breast cancers, visualized on mammography**
- Infant periventricular calcifications seen in congenital Toxoplasmosis
Examples of Dystrophic Calcifications
- Deranged Calcium Metabolism (NOT CELL INJURY)
- Associated w/ increased serum calcium levels (leads to deposition of calcium in other locations)
Metastatic Calcifications
- Hyperparathyroidism
- Vitamin D toxicity
- Chronic Renal Failure
- Formation of Calcium stones in gallbladder, kidney, and bladder are due to precipitation of salts from solution into tissues
Examples of Metastatic Calcifications
- Dead tissue is due to what?
- Infarction
Hypoxic tissue is due to what?
Ischemia
What predisposes a patient to events of thrombosis and emboli?
Atherosclerosis
Result in localized ischemia and subsequent cerebral infarction
Both thrombosis and embolic events
Cerebral infarcts are designated as which 2 things?
- Hemorrhagic
- Bland/White
Cerebral infarcts caused by what are sites of hemorrhage?
Embolization
Cerebral infarcts caused by what are largely ischemic and therefore bland/white/anemic?
Thrombotic occlusion
Occludes vascular flow abruptly, after which the ischemic region undergoes necrosis
Embolus
Progresses more slowly, guards against secondary hemorrhage.
Thrombosis
What are the 2 “pathological cerebral infarcts?”
Which one has astrogliosis?
- Remote Cerebral Infarct
- Old Cystic Infarct (astrogliosis)
- Where is the most common location of a hypertensive intracerebral hemorrhage?
- Which percent occur here?
- Basal Ganglia - Thalamus
- 75% occur here
A freely movable, intravascular mass that is carried from one anatomic site to another by the blood.
Embolism
(most common form is thromboemboli)
The transformation of the fluid blood into a solid aggregate encompassing blood cells and fibrin.
Thrombus
2 examples of “infarcts”
Red and White Infarcts
Which infarct (red or white) typical of arterial occlusion in solid organs (heart, kidneys, etc).??
White Infarcts
Which infarct (red or white) is typical of venous obstruction involving the intestines (volvulus) or testes (torsion)
Red Infarcts
- Caused by arterial defects that originate during embryonic development when the bifurcation of an artery in the Circle of Willis creates a “Y” shaped configuration
Berry Aneurysm
When the artery from Circle of Willis bifurcates during embryonic development, the circumferential muscluar layer of the parent vessel may fail to interdigitate the 2 branches, what does this create?
(berry aneurysm)
- This creates a point of congenital muscular weakness
- Bridged only by:
- endothelium
- Internal elastic lamina
- slender adventitia
What % of berry aneurysms occur at branch points in Circle of Willis?
Over 90%
If a Berry Aneurysm ruptures, where does the blood go?
Subarachnoid space (between arachnoid membrane and pia mater), would result in “subarachnoid hemorrhage”
W/ a berry aneurysm, bloodstream from the parent vessel exerts pressure on “crotch of Y” which results in what over time?
The endothelium and internal elastic membrane degenerates and fragments
As the endothelium and internal elastic membrane degenerate/fragment, what evolves?
A saccular aneurysm w/ walls formed only by adventitia
Undetected berry aneurysms are found in what % of people older than 55 yrs old?
25%
What is the % mortality of an initial subarachnoid hemorrhage from a ruptured berry aneurysm?
35 - 50%
In 1/3 of patients w/ a ruptured berry, the rupture causes either of which 2 things?
- intracerebral hemorrhage
- intraventricular hemorrhage
What do large berry aneurysms of the internal carotid complex cause?
- Palsies of 3rd, 4th, 6th cranial nerves
- Seizures due to compression of medial aspect of temporal lobe
If you see a metal clip on an x-ray, what does this mean?
Clipping of a Berry Aneurysm
What are the sxs of a subarachnoid hemorrhage from a ruptured berry?
Sudden severe HA, may be followed by a coma
Patients w/ SAH from ruptured berry surviving how many days will start to manifest progressive decline in consciousness due to arterial spasm/consequent cerebral ischemia/infaction/stroke?
3 - 4 days
If a person survives a ruptured berry, what is the risk?
Rebleed (worse prognosis)
- E. coli
- Group B Strep
2 bacterias which cause meningitis in Neonates
H. influenza
Bacterial meningitis in infants (3mo - 3yrs)
Strept. pneumococcus
Bacterial meningitis in adults
N. meningitidis
Bacterial meningitis in crowded conditions (dormitories, military barracks)
