M2-C2-L70 --> Cns Muscle

Front 1

Type I muscle fibers
- color?
- contraction character?
- major protein
- major cell
- major cell enzyme

Back 1

Red

Slow twitch (longer, slower contraction)

Myoglobin

Mitochondria

Mitochondrial enzymes

Front 2

Type I muscle fibers
- Ability to change size
- Conditioning leads to what?

Back 2

Don't change in size much with exersize

Increased Aerobic glycolysis

Front 3

Type II muscle fibers
- color?
- contraction character?
- major molecule
- major cell enzymes x2

Back 3

White

Faster, shorter, and more powerful

Glycogen

Phosphorylase

Enzymes of Embden-Meyerhof pathway (Anaerobic glycolysis)

Front 4

Type II muscle fibers
- Ability to change size (hypertrophy) with what? x2
- Ability to change size (atrophy) with what? x3

Back 4

Anabolic steroids or training

Glucocorticoids, disuse or ischemia

Front 5

Define motor unit and its association with fiber types.

Back 5

Nerve and all it's innervating muscle fibers

Fiber type is determined by nerve.

Front 6

What is the role of:
- ATPase (pH 9.4)
- Reverse ATPase (pH 4.3)

Back 6

Helps demonstrate fiber types

Front 7

List the common stains used to study muscle problems.

Back 7

1. ATPase / Reverse ATPase
2. Non-specific esterase
3. NADH-TR (tetrazolium reductase)
4. Alkaline phosphatase
5. PAS

Front 8

Myotonic Dystrophy would be indicated by what staining test and what would it show?

Back 8

Abnormal Non-specific esterase

Front 9

Most frequent atrophy is due to what?

Back 9

Loss of nerve leading to disintegration of myofibrils,

(small angular fibers with redundant basement membrane)

Front 10

Small group atrophy is indicative of what? x4

Back 10

Cachexia
Metabolic abnormality
Early Dystrophy
Fiber splitting (small fibers)

Front 11

Large group atrophy is indicative of what?

Back 11

Diagnostic of devervation

Front 12

In myopathy, what is the non-specific change seen most often?

Back 12

Fiber splitting

Front 13

What is characteristically high in myotonic dystrophy?

Back 13

Internal nuclei

Front 14

Injury of muscle leads to what pathalogical changes? x3

Back 14

1. Seepage of muscle protein
2. Hyaline

and/or

3. Granular Changes

Front 15

Regenerating fibers have what pathological changes? x3

Back 15

1. Large

2. Basophilic

3. Nuclei with prominent nucleoli

Front 16

Seepage of muscle protein will elevate what?

Back 16

Creatine Kinase (CK)

Front 17

List the steps that occur with muscle injury regeneration.

Back 17

1. Injury

2. Myophagocytosis

3. Regeneration

4. Pan-necrosis healing

Front 18

Define myophagocytosis.

Back 18

Macrophages invade the sarcoplasmic membrane and ingest necrotic debris

Front 19

Regeneration involves what with which cell and structure.

Back 19

Proliferation of satellite cells and "stubs" of muscle fibers.

Front 20

Pan necrosis heals by what?

Back 20

Fibrosis (collagenous scar tissue)

Front 21

What type of fiber changes are characteristic of myotonic dystrophy?

Back 21

Ring fibers

Front 22

What type of fiber changes are characteristic of central core disease?

Back 22

Core fibers

Front 23

What type of fiber changes are characteristic of neurogenic diseases.

Back 23

Target fibers

Front 24

"Moth-eaten" muscle fibers would be indicative of what?

Back 24

Non-specific

Front 25

Vacuoloes would be indicative of what?

- Myopathy x4
- Characteristically seen when?
- Disorders?

Back 25

Muscular dystrophy
Polymyositis
Metabolic myopathy
Toxic myopathy

Periodic paralysis

Storage disorders (glycogen or lipid)

Front 26

Sarcoplasmic masses and nemaline rods are indicative of what?

Back 26

Myopathic changes

Non specific

Front 27

What is seen in large numbers with rod body myopathy?

Back 27

Nemaline rods

Front 28

Ragged red fibers are due to what?

Back 28

Abnormal accumulation of abnormal mitochondria

Front 29

What happens if UMN knocked out with intact LMN?

Back 29

Diffuse nonspecific atrophy

Front 30

Early denervation have what type of fibers?

Back 30

Target fibers

Front 31

Describe the response to denervation.

Back 31

Muscle fibers becomes covered with nicotinic receptors (for ACh)

which will induce nearby nerves to sprout new buds

making contact with the denervated muscle fiber

inducing new synapses.

When new synapse is established, extra receptor fibers will degenerate

Front 32

What is a general pathognomonic of denervation/reinnervation?

Back 32

Fiber type grouping

Front 33

What is a general pathognomonic of denervation?

Back 33

Large group atrophy

Front 34

Infantile Spinal Muscular Atrophy

- inheritance
- symptoms
- prognosis
- pathology

Back 34

AR

Extreme weakness at birth (floppy baby)
Progressive loss of motor function (LMN loss)

Less than 3 years

Small rounded fibers with hypertrophyic type I fibers.

Front 35

Define muscular dystrophy

Back 35

Hereditary
Progressive
Noninflammatory
Degenerative

Muscle disease

Front 36

Duchenne's muscular dystrophy would be most severe in what regions?

Back 36

Pelvic and shoulder

Front 37

Describe the genetics of Duchenne's muscular dystrophy.

Back 37

X-linked recessive

Deletion of gene on p arm of X

Results in absence of dystrophin

Front 38

Compare Duchenne's muscular dystrophy with Becker's muscular dystrophy.

Back 38

Same gene, different allele

Becker's is less severe

Begins later and slower in progression

Front 39

Where is dystrophin usually found?

Back 39

Inner surface of sarcolemma

Front 40

Function of dystrophin?

Back 40

Links subsarcolemmal cytoskeleton to glycoprotein-bound laminin.

Front 41

What is the most common cause of death in patients with Duchenne's?

Back 41

Respiratory failure

Pulmonary infections

Cardiac arrhythmias (and failure)

Front 42

Describe the early pathology in Duchenne's. 4

Back 42

Increased variation if fiber size

Increased internal nuclei

Degeneration, necrosis, myophagocytosis

Brisk regeneration period

Front 43

Describe the late pathology in Duchenne's. x2

Back 43

Fibrosis with fibrofatty replacement

and overall muscle atrophy

Front 44

What is the most common form of muscular dystrophy in adults?

Back 44

Myotonic dystrophy

Front 45

Describe the pathogenesis of Myotonic dystrophy. x2

Back 45

AD

Anticipation with CTG repeats

Front 46

Clinical feature of myotonic dystrophy

Back 46

Myotonia

Distal weakness

Front 47

Pathology of Myotonic dystrophy. x4

Back 47

Hypertrophy of type II

Atrophy of type I

Internal nuclei numerous

Ring fibers

Front 48

Congenital myopathy

- clinical signs x3
- test results
- progressiveness
- examples x3

Back 48

Hypotonia
Decreased DTR
Decreased muscle bulk

Normal creatine kinase

Non progressive

Central Core disease
Rod (nemaline) myopathy
Central nuclear mypathy

Front 49

Central core diseases

- clinical signs x4
- test results
- progressiveness
- genetics
- Pathology x2

Back 49

Proximal muscle weakness
Hypotonia
Decreased DTR
Decreased muscle bulk

Normal creatine kinase

Non progressive

Sporadic, AR, or AD

Type 1 predominance
Central zone degeneration

Front 50

Rod (nemaline) myopathy

- clinical signs
- associated with?
- test results
- progressiveness
- pathology x2

Back 50

Proximal limb weakness, face, pharnx, and neck
Hypotonia
Decreased DTR
Decreased muscle bulk

Kyphoscoliosis

Normal creatine kinase

Non progressive

Predominance of Type I
Red and Black rods in cytoplasm

Front 51

Central Nuclear Myopathy

- inheritance types with signs

- AKA?

Back 51

X linked - weak & hypotonic (death in neonates)

AD - later onset, slowly progressive

myotubular myopathy

Front 52

Pathology of Central nuclear myopathy. x3

Back 52

Type 1 predominance

Central nuclei esp. in type 1 fibers

Fibers small, round, with central nuclei.