Msck - disease of the Skeletal muscle Flashcards
immunohesitochemistry used to stain Monocytes
NADH-HR
Myosin ATP-ase; pH: 4.3 Vs Myosin ATP-ase; pH: 9.4 for Type I/II muscle fibers
Type I vs Type IIA vs Type IIB muscle fibers on Histology
Denervation Atrophy invloves ——– fibers
Type I and Type II fibers
Disuse Atrophy involves —— fibers
Type II fibers only
* unlike Denervation atrophy which involved type I and II
Causes of Disuse Atrophy
Prolonged immobilisation
(not using muscles enough so –> muscles break down and decrease in size)
Histology of Denervation Atrophy:
▪ Involvement of ——– fibres
▪ Small and ———- as well as ———-
▪ Fibre ———–, after re-innervation
▪ Involvement of both type I and type II fibres
▪ Small and angular fibers as well as target fibres
▪ Fibre type grouping, after re-innervation
Histopatho:
▪ Involvement of both type I and type II fibres
▪ Small and angular fibers as well as target fibres
▪ Fibre Type grouping, after re-innervation
features of?
Denervation Atrophy
what do you obsever , what condition causes this?
Target fibers caused by Denervation Atrophy
* traget fibers are normally found on type I fibers
Histology of Disuse Atrophy:
——— of type II fibers
Angular Atrophy of type II fibers
Muscular Dystrophies examples
1) Duchenne Muscular Dystrophy
2) Becker Muscular Dystrophy
CF of muscular dystrophies
Progressive muscle wasting and weakness due to degenration of Skeletal muscles
Lab findings of Muscular Dystrophies
Increased serum Creatine kinase (CK)
cause of Duchenne muscular dystrophy
X-linked disroder –> De novo mutations of the Dystrophin gene (Deficiency of Dystrophyin)
* X-linked recessive
Epi of Duchenne muscular dystrophy
- Male children
- most common/sever muscular dystrophy
Duchenne muscular dystrophy
Microscopic findings:
- Random variation in muscle fibre ——–
- ———— perimysial and endomysial fibrosis
- Basophilic regenerating myotubes
- Amorphous pink cytoplasm in —————
- Many, irregularly scattered ———–
- Random variation in muscle fibre size
- moderate perimysial and endomysial fibrosis
- Basophilic regenerating myotubes
- Amorphous pink cytoplasm in necrotic msucle
- Many, irregularly scattered hyaline fibers
Microscopic features:
- Random variation in muscle fibre size
- moderate perimysial and endomysial fibrosis
- Basophilic regenerating myotubes
- Amorphous pink cytoplasm in necrotic msucle
- Many, irregularly scattered hyaline fibers
features of?
Duchenne muscular dystrophy
Lab findings of Duchenne Muscular dystrophy
Increased serum CK