parakeratosis


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parakeratosis

 [par″ah-ker″ah-to´sis]
persistence of the nuclei of keratinocytes as they rise into the horny layer of the skin; it occurs normally in the epithelium of the true mucous membrane of the mouth and vagina.

par·a·ker·a·to·sis

(par'ă-ker'ă-tō'sis),
Retention of nuclei in the cells of the stratum corneum of the epidermis, observed in many scaling dermatoses such as psoriasis and subacute or chronic dermatitis.

parakeratosis

/para·ker·a·to·sis/ (-ker″ah-to´sis) persistence of the nuclei of keratinocytes as they rise into the stratum corneum of the epidermis. It is normal in the epithelium of the true mucous membrane of the mouth and vagina.

parakeratosis

[-ker′ətō′sis]
an abnormal formation of horn cells of the epidermis caused by the persistence of nuclei, incomplete formation of keratin, and moistness and swelling of the horn cells. It is observed as scaling in many conditions such as psoriasis.
enlarge picture
Parakeratosis pustulosa

par·a·ker·a·to·sis

(par'ă-ker'ă-tō'sis)
Retention of nuclei in the cells of the stratum corneum of the epidermis, observed in many scaling dermatoses such as psoriasis and subacute or chronic dermatitis.

par·a·ker·a·to·sis

(par'ă-ker'ă-tō'sis)
Retention of nuclei in the cells of the stratum corneum of the epidermis, observed in many scaling dermatoses such as psoriasis and subacute or chronic dermatitis.

parakeratosis (per´əkerətō´sis),

n the persistence of nuclei in the stratum corneum keratin layer of stratified squamous epithelium. Associated with the masticatory mucosa of the attached gingiva; may be an immature form of orthokeratinized epithelium.

parakeratosis

persistence of the nuclei of keratinocytes as they rise into the horny layer of the skin; it occurs normally in the epithelium of the true mucous membrane of the mouth and vagina. When it occurs on the external skin it constitutes a lesion. The appearance is of thickening of the skin with thick scale formation, cracking and fissuring, and an underlying raw red surface. Occurs as a specific disease in pigs fed on rations deficient in zinc; the effect is exacerbated on diets high in calcium.

inherited parakeratosis
occurs in calves, which are normal at birth but develop parakeratosis all over the body, especially on the legs and die after a long illness. Responds to treatment with zinc given orally. See also thymic hypoplasia. Called also lethal trait A46, adema disease.
ruminal parakeratosis
the ruminal papillae are enlarged, leathery and adhered in clumps. The lesion is most severe in the dorsal part of the sac. Occurs principally in animals fed pelleted feed.
References in periodicals archive ?
Skin biopsy is often not diagnostic, but may show alternating parakeratosis and orthokeratosis (as in this case).
The cytological findings such as squamous metaplasia, hyperkeratosis, parakeratosis, and reactive cellular changes were noted specifically in patients with or without uterine prolapse.
The overlying basket- wave keratin is replaced by abnormal hyperkeratosis and parakeratosis.
18 Changes in epithelium observed in the patients with OSF shows mostly epithelial atrophy, or epithelial hyperplasia, keratosis with either hyper orthokeratosis or hyper parakeratosis, pyknosis in basal layer nuclei, lack of glycogen in severe Grade III scenarios, intercellular edema, hyalinization occurring close to epithelium and collagen with diverse thickness19 vacuolization of prickle-cell layer, amplified mitotic activity, Increased levels of pro-inflammatory cytokines and reduced antifibrotic interferon have also been demonstrated in patients with OSF and atypical epithelium changes20 with moderate epithelial hyperplasia eventually resulting in squamous cell carcinoma.
A second histopathological was performed in the erythematous, scaly lesions (knees), revealing epidermis with acanthosis psoriaseforme, parakeratosis, and neutrophils accumulation in the stratum corneum (Munro microabscesses).
A skin biopsy taken from the arm showed epidermal hyperkeratosis, focal parakeratosis, exocytosis, diffuse lysis of the basal layer, band-like lymphocytic infiltration of the dermis, lymphocytic infiltrate around the hair follicle, and scattered melanin incontinence (Figure-2a).
Ruminal acidosis and the rapid onset of ruminal parakeratosis in a mature dairy cow: a case report.
Microscopic changes included thickening of epidermis, elongated growth of papillary projections extending into dermis along with hyperkeratosis, parakeratosis and acanthosis (Fig.
Histopathologic features are diverse degrees of orthokeratosis and parakeratosis besides thickness of spinous layer.
Since true leuconychia is thought to be due to abnormal matrix keratinization, with persistent parakeratosis and keratohyaline granules in the nail plate, so parakeratosis and dissociation of the keratin bundles may play a role in the modification of the solar light reflection by the ungual plates2.
Histopathologic analysis revealed features typical of benign cutaneous warts, including acanthosis, parakeratosis, and numerous koilocytes (Figure 1), similar to warts caused by HPV-3 (8).
Mature lesions exhibit parakeratosis alternating with hyperkeratosis, epidermal acanthosis, Munro microabscesses and dermal perivascular infiltrate containg neutrophils, lymphocytes and macrophages.