麻省理工大学：《生物材料——组织交互作用》教学讲义（英文版）A theory of induced regeneration in adults

2.79J2.79/396J/BE441J/HST522J A theory of induced regeneration in adults. Note: [C, s, R] data only cited no kinetics

2.79J/2.79J/3.96J/BE.441J/HST.522J A theory of induced regeneration in adults. Note: [C, S, R] data only cited; no kinetics

Outline 1. reversible inju 2. Regenerative and nonregenerative tissues 3. Antagonistic relation between contraction and regeneration 4. Present theory: Selective inhibition of contraction necessary but not sufficient for regeneration 5. Mechanism

Outline 1. Irreversible injury 2. Regenerative and nonregenerative tissues 3. Antagonistic relation between contraction and regeneration 4. Present theory: Selective inhibition of contraction necessary but not sufficient for regeneration 5. Mechanism

1. Irreversible injury

1. Irreversible injury

Reversible iniury Image removed due to copyright considerations See Figure 1.1 in Yannas, I. V. Tissue and Organ Regeneration in Adults. New York: Springer-Verlag, 2001 Spontaneous regeneration of amputated limb in the newt occurs independently of severity of injury Goss, 1992

Reversible injury Image removed due to copyright consi derati ons. See Figure 1.1 in Yannas, I. V. Tissue and Organ Regeneration in Adults. New York: Springer-Verlag, 2001. Image removed due to copyright consi derations. See Figure 1.1 in Yannas, I. V. Tissue and Organ Regeneration in Adults. New York: Springer-Verlag, 2001. Spontaneous regeneration of amputated limb in the newt occurs independently of severity of injuryGoss, 1992

reversible inury Image removed due to copyright considerations Burn victim suffering from severe contraction and scar formation Tomasek et al 2000

Irreversible injury Image removed due to copyright consi derati ons. Image removed due to copyright consi derations. Burn victim suffering from severe contraction and scar formation Tomasek et al., 2000

2. Regenerative and nonregenerative tissues in adult mammals

2. Regenerative and nonregenerative tissues in adult mammals

The tissue triad in skin and nerves Nerve Skin Axon epidermis basement membrane Basement membrane. Myelin sheath Endoneurium dermis Perineurium

The tissue triad in skin and nerves

Skin Defect site The epidermis is a regenerative tissue. After excision, it regenerates spontaneously Reversible injury. No contraction

Skin The epidermis is a regenerative tissue. After excision, it regenerates spontaneously. Reversible injury. No contraction

Skin The dermis is a nonregenerative tissue in the adult. After excision it does not regenerate spontaneously Irreversible injury. Contraction occurs with scar formation

The dermis is a nonregenerative tissue in the adult. After excision, it does not regenerate spontaneously. Irreversible injury. Contraction occurs with scar formation. Skin

Peripheral nerve Compressive force crushed nerve heals spontaneously healing basement membrane b regeneration The myelin sheath is a regenerative tissue Following nerve crushing with myelin disruption, the myelin regenerates spontaneously Reversible injury. No contraction

Peripheral nerve The myelin sheath is a regenerative tissue. Following nerve crushing with myelin disruption, the myelin regenerates spontaneously. Reversible injury. No contraction. crushed nerve heals spontaneously by regeneration