Pa8-Wound Healing I

Front 1

What is regeneration?

Back 1

Prolif of cells & tissues to replace lost structures. (eg liver, hematopoetic cells, skin, & epi of GI tract)

Front 2

What is repair?

Back 2

A hybrid of regeneration & scar formation w/ some restoration & some structural derangement

Front 3

What is scar formation?

Back 3

Deposition of collagen

Front 4

What are the completely renewing tissues?

Back 4

Blood, skin, & epi of GI

Front 5

What is the normal homeostasis of healing?

Back 5

A balance of prolif, differentiation, & cell death

Front 6

What are the 3 groups of tissue prolif activity?

Back 6

Labile, Stabile, & Permenant tissues

Front 7

What are labile tissues? Examples.

Back 7

Continuously divide throughout life span. (eg stratified squamous epi of skin, oral, vagina, cervix. Lining of glands, columnar epi of GI, Uroepi of urinary trat. Bone marrow & hematpoietic system

Front 8

What are stabile tissues? Examples.

Back 8

Quiescent; low level of replication only when need to. Rapid division in response to stimuli. (eg Parenchymal: liver, kidney, pancreas. Mesanchymal: fibroblasts & smooth m. WBC & vascular endothelial cells

Front 9

What are permanent tissues? Examples.

Back 9

Non-dividing; cells no longer in cell cycle postnatally. (eg neurons, skeletal m, cardiac m)

Front 10

What are the charac of stem cells?

Back 10

Self-renewal & capacity to generate differentiated cell lineages

Front 11

What are the 2 mech of stem cell maintainence?

Back 11

Obligatory assymetric replication & stochastic differentiation

Front 12

Charac ofobligatory assymmetric replication?

Back 12

With ea division, 1 cell retains self-renewal capacity & the other enters a differentiation pathway

Front 13

Charac o stochastic differentiation?

Back 13

Balance b/w 2 division processes: 1) those which make 2 self-renewing stem cells & 2) those which make 2 cells that differentiate

Front 14

What are emryonic stem cells?

Back 14

Pluripotent cells from the inner cell mass of blastocyst. Can differentiate into any cell type. Used to make knockout mice. Hoped to repopulate damage organs

Front 15

What are the 2 types of cloning?

Back 15

Induced pluripotent & therapueutic cloning.both are inefficient & inaccurate

Front 16

Charac of induced pluripotnet stem cells.

Back 16

Differentiated cells are pregrogrammed by transfering nuc of adult stem cell into enucleated oocyte. Use surrogate mother to clone embryo

Front 17

What is therapeutic cloning?

Back 17

Nuclear transfer into oocyte for treatment of human diseases. Take nuc from skin fibroblasr + human oocyte-> embryonic stem cell in culture

Front 18

Why is cloning inaccurate?

Back 18

Deficiency in histone methylation in reprogrammed embryonic stem cells, which results in improper gene expression

Front 19

What are the charac of adult/somatic stem cells?

Back 19

Present in tissures which contin divide. (skin, bone marrow, linig of GI)

Front 20

What stem cells are important in regeneration & maintainence?

Back 20

bone marrow, liver, brain, skin, cornea, intestinal epi, skeletal, cardiac m

Front 21

Where are stem cells located in the skin?

Back 21

Hair follicle bulge, sebaceous glands, & interfollicular area of surface epi

Front 22

How is replication stim?

Back 22

Growth factors & signaling from EC matrix via integrins

Front 23

How is cell cycle progression regulated?

Back 23

Cyclins, CDK, catalytic activation, phosphorylation, inhibition

Front 24

What is the importance of cell cycle check points?

Back 24

Sense DNA & chrom damage, not allow damaged cells to contin, G1/S checks before preplication, G2/M checks after replication. Apop or senescence if damaged

Front 25

What are growth factors?

Back 25

Polypeptides that re ligands w/ specific receptors->stim transcription of genes

Front 26

How are EGF & TGF-alpha similar?

Back 26

Share a common receptor. EGFR is a family of 4 receptors w/ intrinisic kinase activity. ERB B2/Her2 overexpressed in breast cancer

Front 27

Fcn of HGF?

Back 27

Mitogenic effect on hepatocytes & mose epi cells. Required for survival during embryonic development

Front 28

Fcn of PDGF?

Back 28

3 isoforms, sored in plts & released upon plt activation

Front 29

Fcn of VEGF?

Back 29

Induces blood vessel formation. Promotes angiogenesis in chronic inflammation, wound healing, & tumors

Front 30

Fcn of FGF?

Back 30

Involved in wound repair, hematopoiesis, development

Front 31

What are te 3 signaling mech?

Back 31

Autocrine (liver & tumor), paracrine (wounds-fibroblasts & macros), & endocrine

Front 32

What are the 4 types of receptors?

Back 32

Intrinisic kinase activity, extrinsic kinase, G-protein, & steriod hormone receptors

Front 33

Charac of intrinisic kinase receptors?

Back 33

Most GF, extracell ligand binding domain, transmembrane region, cytoplasmic tail w/ kinase activity. (alterations in activity-> cancer)

Front 34

Charac of extrinisic kinase receptors?

Back 34

Many cytokines, GH, prolactin. Transmit signals to the nuc via JAKs

Front 35

Charac of G-protein receptors?

Back 35

Transmit siganl through trimeric GTP-binding proteins, act vis conformational changes, cAMP as 2nd messenger. 7 transmembrane alpha helices, targeted by many drugs

Front 36

Charac of steroid hormine receptors?

Back 36

Located in nuc, fcn as ligand-dependent transcription factors. (thyroid hormone & Vit D)

Front 37

Charac of transcription factors?

Back 37

Fcn in heterodimer formation, phosphorylation, & release inhibition. Cellular events requiring rapid responses rely on post-translationsl modification