Other Keratin Disorders

The spectrum of keratin disorders also encompasses a number of extracutaneous diseases. Meesmann corneal dystrophy (MSD) is inherited in an autosomal-dominant fashion with incomplete penetrance. Slit lamp identification of typical fine, round cysts in the corneal epithelium aids in differentiating this disorder from other inherited corneal dystrophies.[33] Although vision is only rarely impaired to a serious degree in MSD, cyst rupture can cause corneal erosions and intermittent decrease in visual acuity during adulthood.[33] The disorder results from dominant mutations in K3 and K12 genes that are specifically expressed in the corneal epithelium.[2]

Recent studies have revealed that mutations in keratins expressed in simple epithelia may be involved in the pathogenesis of a number of gastrointestinal diseases.[20] Cryptogenic cirrhosis is a diagnosis of exclusion applicable to an individual with cirrhosis who does not carry a hepatitis B or C virus; who does not test positive for serological markers associated with autoimmune hepatitis or primary biliary cirrhosis; who has normal iron, ceruloplasmin, and aj-antitrypsin levels; and who has no history of alcohol or toxin ingestion. Recurrent mutations in human K8/K18 genes have been shown to predispose individuals to cryptogenic cirrhosis, chronic pancreatitis, and inflammatory bowel disease.[20,34,35] How K8/K18 mutations cause liver disease is still a matter of debate. Animals deficient in K8/K18 are highly susceptible to proapoptotic signals, suggesting that keratins may play a cytoprotective role in the gastrointestinal tract.[20]

Getting Started With Dumbbells

Getting Started With Dumbbells

The use of dumbbells gives you a much more comprehensive strengthening effect because the workout engages your stabilizer muscles, in addition to the muscle you may be pin-pointing. Without all of the belts and artificial stabilizers of a machine, you also engage your core muscles, which are your body's natural stabilizers.

Get My Free Ebook

Post a comment