57) Mixed tumor of skin is morphologically identical to pleomorphic adenoma of the salivary gland, exhibiting secondary structures such as glands/ducts, cysts, keratinous
cysts, and foci of squamous differentiation, with a mucoid stroma typically showing cartilaginous metaplasia (hence also known as chondroid syringoma).
Produces: phospholipase , peroxidase , chitinolytic enzymes , [+ or -]-amylase , strong amylolythic activity, keratinolytic serine proteinase very specific for keratinous
substrates such as elastin, keratin and type I collagen; strong keratinolytic activitiy  6 As no.
Contents of the cyst can be keratinous
, casseous, sebaceous or purulent.
Along with that there was prominent chondrosarcomatous areas (Figure 1E and 1F) and extensive squamous metaplasia with formation of numerous epidermal cysts of keratinous
type (Figure 1G).
The shell is composed of individual bony segments, with overlying keratinous
plates called scutes.
Some suggested that this could be due to intense inflammation caused by implanted keratinous
material which acts as foreign body in the dermis and subcutis.
Clinically, NC is characterized by closely arranged, dilated follicular openings with dark keratinous
plugs resembling blackheads (open comedones) .
Histologically, dermoid cysts are lined with stratified epithelium resembling normal skin with adnexa and filled with keratinous
material (Munoz et al.
Other researchers report that C cladosporioides fungal biomass mixed with keratinous
material of natural origin remove 100 mg gold/g of biomass and the maximal biosorption of the precious metal (80%) occurs under acidic conditions (pH 1-5) .
Poultry feather is the most abundant keratinous
material in nature accumulated as a byproduct residual from the poultry processing industry and contains protein in high quantity up to 90% (Karthikeyan et al.
Most of the extractable keratinous
protein is contained within cortical cells, but significant and important tractions are present within cuticle (Powell and Rogers, 1986; Dawber, 1996).
Typically beginning as coppery colour papules and macules, that develop a hyperkeratotic surface and central keratinous