III - Tissue Repair, Healing and Fibrosis Flashcards
Type of tissue whose cells can readily regenerate as long as the pool of stem cells is preserved.
Labile tissues(TOPNOTCH)Robbins Basic Pathology, 8th ed. p.61
Cells of theses tissues are quiescent and have only minimal replicative activity in their normal state. Capable of proliferating in response to injury or loss of tissue mass.
Stable tissues(TOPNOTCH)Robbins Basic Pathology, 8th ed. p.61
Cells of these tissues are considered to be terminally differentiated and nonproliferative in postnatal life.
Permanent tissues(TOPNOTCH)Robbins Basic Pathology, 8th ed. p.62
Labile, stable or permanent tissues:Bone marrow
Labile(TOPNOTCH)Robbins Basic Pathology, 8th ed. p.61
Labile, stable or permanent tissues:Vaginal epithelium
Labile(TOPNOTCH)Robbins Basic Pathology, 8th ed. p.61
Labile, stable or permanent tissues:Salivary glands
Labile(TOPNOTCH)Robbins Basic Pathology, 8th ed. p.61
Labile, stable or permanent tissues:Liver parenchyma
Stable(TOPNOTCH)Robbins Basic Pathology, 8th ed. p.61
Labile, stable or permanent tissues:Endothelium
Stable(TOPNOTCH)Robbins Basic Pathology, 8th ed. p.61
Labile, stable or permanent tissues:Smooth muscle cells
Stable(TOPNOTCH)Robbins Basic Pathology, 8th ed. p.61
Labile, stable or permanent tissues:Neurons
Permanent(TOPNOTCH)Robbins Basic Pathology, 8th ed. p.62
Labile, stable or permanent tissues:Cardiac muscle
Permanent(TOPNOTCH)Robbins Basic Pathology, 8th ed. p.62
Type of collagen found in basement membrane
Type IV collagen(TOPNOTCH)Robbins Basic Pathology, 8th ed. p.67
Most abundant glycoprotein in basement membrane
Laminin(TOPNOTCH)Robbins Basic Pathology, 8th ed. p.68
The pink, soft, granular tissue seen beneath the scab of a skin wound. It has small blood vessels and fibroblast proliferation.
Granulation tissue(TOPNOTCH)Robbins Basic Pathology, 8th ed. p.70
Maturation and reorganization of fibrous tissue
Remodeling(TOPNOTCH)Robbins Basic Pathology, 8th ed. p.70
Healing of a clean, uninfected surgical incision approximated by surgical sutures
Healing by first intention / Primary Union(TOPNOTCH)Robbins Basic Pathology, 8th ed. p.74
Type of healing wherein tissue is allowed to heal by itself before suturing. Used in large wounds, in the presence of abscess, or ulceration.
Healing by secondary intention / secondary union(TOPNOTCH)Robbins Basic Pathology, 8th ed. p.76
Wound strength reaches 70 - 80 % of normal in ______ months.
3 months(TOPNOTCH)Robbins Basic Pathology, 8th ed. p.77
Single most important cause of delay in wound healing.
Infection(TOPNOTCH)Robbins Basic Pathology, 8th ed. p.77
True or false: Complete restoration can occur only in tissues composed of stable and labile cells.
True(TOPNOTCH)Robbins Basic Pathology, 8th ed. p.77
Arrange the steps in cutaneous wound healing:A. Formation of granulation tissueB. ECM remodelingC. Inflammation
C, A, B(TOPNOTCH)Robbins Basic Pathology, 8th ed. p.72
True or false: Injury to tissues composed of permanent cells does not result to scarring.
False. Injury to tissues composed of permanent cells, inevitably results to scarring.(TOPNOTCH)Robbins Basic Pathology, 8th ed. p.77
Process of replacing damaged components of a tissue, returning to a normal state.
Regeneration (TOPNOTCH)Robbins Basic Pathology, 8th ed. p.77
Migration and proliferation of fibroblasts with deposition of ECM.
Scar formation(TOPNOTCH)Robbins Basic Pathology, 8th ed. p.72
Maturation and reorganization of fibrous tissue
Remodeling(TOPNOTCH)Robbins Basic Pathology, 8th ed. p.73
Enzymes promote DNA replication and various aspects of mitosis. They are required for cell cycle progression. Forms complexes with cyclin.
Cyclin-dependent kinases (CDK)(TOPNOTCH)Robbins Basic Pathology, 8th ed. p.61
Cytokine is released from activated macrophages, Mitogenic for keratinocytes and fibroblasts. Also stimulates keratinocyte migration and granulation tissue formation.
Epidermal Growth Factor (EGF)(TOPNOTCH)
This cytokine increases vascular permeability and is mitogenic for endothelial cells.
Vascular Endothelial Growth Factor (VEGF)(TOPNOTCH)Robbins Basic Pathology, 8th ed. p.71
Pattern of extracellular signaling wherein the target cell is itself.
Autocrine(TOPNOTCH)
Pattern of extracellular signaling wherein the target cell is adjacent to the secretory cell.
Paracrine(TOPNOTCH)
Pattern of extracellular signaling wherein the target cell is distant to the secretory cell.
Endocrine(TOPNOTCH)
A 33 year old man sustains a stab injury on his right forearm. Two days after the incident, what can be seen in his stab wound? (A) dense collagen deposition (B) pink amorphous material devoid of cellular elements (C) accumulation of fibroblasts and macrophages (D) fibroblasts and capillaries in a loose extracellular matrix
Fibroblasts and capillaries in a loose extracellular matrix (TOPNOTCH) Robbins Basic Pathology, 8th ed. Pp 70-71
What is expected in the surgical scar of a 21 year old who underwent appendectomy one month ago? (A) Absence of dermal appendages (B) fibroblasts and capillaries in a loose extracellular matrix (C) intense intlammation and large amounts of granulation tissue (D) peak neovascularization
Absence of dermal appendages (Healing by First Intention) (TOPNOTCH) Robbins Basic Pathology, 8th ed. Pp74-76
Cell responsible for wound contraction, especially in wounds that heal by second intention. Also produces collagen.
Myofibroblast (TOPNOTCH) Robbins Basic Pathology 8th ed, p 76
True or False. Granulation tissue is more prominent in healing by secondary union.
True (TOPNOTCH)
Hypertrophic scar is due to accumulation of excessive amount of___.
Collagen (TOPNOTCH)
Synthesized by mesenchymal cells, present in the spaces between cells in connective tissue, between epithelium and supportive vascular and smooth muscle structures.
Interstitial Matrix(TOPNOTCH)
Component of ECM which confers tensile strength and recoil.
Fibrous proteins s.a. Collagen and elastin(TOPNOTCH)
Component of ECM that permits resilience and lubrication.
Proteoglycans, hyaluronan(TOPNOTCH)
Component of ECM that connect the elements to one another and to the cells.
Adhesive glycoproteins(TOPNOTCH)
What is the hallmark of tissue repair?
Tissue granulation. (TOPNOTCH)
A 28 y/o male suffered from traumatic injury of the muscles of his left lower extremity. In this type of tissue, repair is typically dominated by? Scar formation or regeneration?
Scar formation. In permanent tissues like skeletal and cardiac muscle, repair is dominated by scar formation. (TOPNOTCH) Robbins Basic Pathology, 9th ed., p. 101
Liver, kidney and pancreas. Labile, stable or permanent tissues?
Stable. (TOPNOTCH) Robbins Basic Pathology, 9th ed., p. 101
A patient has a large wound on his right arm as a result of a vehicular crash. Initially his wound is filled with granulation tissue composed of fibroblast and new blood vessels. What is responsible for inducing formation of new blood vessels?
Vascular Endothelial Growth Factor (VEGF)(TOPNOTCH)
Following hepatectomy, liver undergo repair by __________.
Regeneration. (TOPNOTCH) Robbins Basic Pathology, 9th ed., p. 102
Steps in scar formation
Angiogenesis, Formation of granulation tissue, Remodelling. (TOPNOTCH) Robbins Basic Pathology, 9th ed., p. 102
It is characterized by proliferation of fibroblast and new thin walled, delicate capillaries in a loose ECM often admixed with inflammatory cells.
Granulation tissue. (TOPNOTCH) Robbins Basic Pathology, 9th ed., p. 103
Roles of macrophage in tissue repair.
Clear offending agent and dead tissue, provide growth factor, secrete cytokines for fibroblast proliferation and connective tissue synthesis.(TOPNOTCH) Robbins Basic Pathology, 9th ed., p. 104
Granulation tissue appear after how many days after injury?
3-5 days. (TOPNOTCH) Robbins Basic Pathology, 9th ed., p. 104
A 50 y/o coal worker experienced gradual onset of dyspnea and non-productive cough. He was then diagnosed with pulmonary fibrosis. What is the most important cytokine that causes the development of fibrosis following chronic inflammation?
Transforming growth factor-? (TGF-?) is the most important cytokine for synthesis and deposition of connective tissue protein. (TOPNOTCH) Robbins Basic Pathology, 9th ed., p. 105
A 52 y/o diabetic female patient developed a non-healing wound on his right foot. She is currently on an anti-hyperglycemic and an antihypertensive.What factor is the most likely implicated in the abnormal wound healing?
Presence of uncontrolled blood glucose level/Diabetes. (TOPNOTCH)
Cells present within 24 hours of tissue injury.
Neutrophils (TOPNOTCH) Robbins Basic Pathology, 9th ed., p. 106
Predominant cells on Day 3 after tissue injury
Macrophages.(TOPNOTCH) Robbins Basic Pathology, 9th ed., p. 106
An important feature in healing by secondary intention/secondary union.
Wound contraction involving formation of myofibroblasts at the edge of the wound. (TOPNOTCH) Robbins Basic Pathology, 9th ed., p. 108
True or False. Wound strength returns to normal 3 months after a carefully sutured wound.
False. Only up to 70-80% of normal and usually does not improve beyond that. (TOPNOTCH) Robbins Basic Pathology, 9th ed., p. 108
Patient X had a laceration on his right arm and underwent suture and repair. Wound healing continues, however, the site was disfiguring and developed a raised nodule after 2 months. The abnormality presented is ___.
Keloid formation (TOPNOTCH)
Patient receiving glucocorticoid therapy for the autoimmune disease developed an abscess. Poor wound healing may result from glucocorticoid therapy due to:
Inhibition of TGF-B and diminished fibrosis secondary to glucocorticoid therapy. (TOPNOTCH) Robbins Basic Pathology, 9th ed., p. 106
One week after an exploratory laparatomy, a 30-year old obese female patient had “rupture of the wound”. This complication in tissue repair is due to inadequate formation of granulation tissue or scar formation.
Dehiscence. (TOPNOTCH) Robbins Basic Pathology, 9th ed., p. 109
A 5 y/o patient had second degree burn of the palms. She is more prone to what type of abnormality in tissue repair?
Contracture. (TOPNOTCH)
Collagen deposition in cellular repair is largely a function of what cells?
Fibroblasts (TOPNOTCH)
The hallmark of tissue healing is:
Granulation tissue (TOPNOTCH)
Vitamin C retards wound healing because
Collagen synthesis is inhibited (TOPNOTCH)
Phase of cutaneous wound healing: formation of granulation tissue, proliferation and migration of connective tissue cells and re-epithelialization of wound surface
Proliferation (2nd phase) (TOPNOTCH)
Phase of cutaneous wound healing: ECM deposition, tissue remodeling and wound contraction
Maturation (3nd phase) (TOPNOTCH)