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Geriatric hair and scalp disorders
Published in Robert A. Norman, Geriatric Dermatology, 2020
The stratum corneum shows focal parakeratosis. The epidermis shows mild to moderate acanthosis and spongiosis with mononuclear cells contained within the spongiotic areas. There is a mild mononuclear infiltrate in the dermis.
Experimental Oral Carcinogenesis
Published in Samuel Dreizen, Barnet M. Levy, Handbook of Experimental Stomatology, 2020
Samuel Dreizen, Barnet M. Levy
Biopsies that were taken during the first 6 months of either treatment revealed ulceration, inflammation, and healing in the later months. By the 9th month following the insertion of the basic betel quid, there was epithelial hyperplasia with areas of squamous atrophy where scarring had ocurred. Increased parakeratosis was common. After 12 months of treatment, the histologic appearance was similar in all of the five baboons which had received only the basic betel quid. The basal cell nuclei showed more spindling and were hyperchromatic. More inflammatory cells were present than in the earlier biopsies. By the end of 30 months, all of the baboons in the basic betel quid group demonstrated ulcerative hemorrhagic lesions in the buccal pouch, but none exhibited malignant change.
The skin
Published in C. Simon Herrington, Muir's Textbook of Pathology, 2020
Hyperkeratosis – Thickening of the epidermal corneal layer, either with retained nuclei (parakeratosis) or without (orthokeratosis). Parakeratosis is the histological correlate of ‘scale’ seen clinically.
Inverse pityriasis rosea secondary to COVID-19 vaccination
Published in Baylor University Medical Center Proceedings, 2022
Blayne Fenner, Jessica L. Marquez, Meredith Pham, Michelle Tarbox
Physical examination revealed erythematous papules and plaques with a trailing scale distributed predominantly in the axilla, inframammary, and groin area, with a total body surface area of around 5% (Figure 1). Dermoscopy revealed a collarette of scale as well as central yellow hue with a peripheral reddish background (Figure 2a). Two 4-mm punch biopsies were performed, one on the first reported lesion under her left breast and the other on a lesion in the groin. Pathology revealed areas of confluent parakeratosis as well as mounds of parakeratosis. Moderate psoriasiform hyperplasia of the epidermis with moderate spongiosis, moderate inflammatory infiltrate of lymphocytes with eosinophils in the dermis, extravasation of red blood cells, and moderate exocytosis of lymphocytes into the epidermis were also observed on histopathology (Figures 2b–2d). A periodic acid-Schiff stain was negative for fungus or yeast. The histologic differential at this point included psoriasis, PR, subacute to chronic eczema, and contact dermatitis. The patient was given topical corticosteroids. Two weeks later, she reported improvement in her symptoms with almost complete resolution of the rash and pruritus.
Pediatric Sloughing Esophagitis: A Case Report and Discussion
Published in Fetal and Pediatric Pathology, 2018
Lulu Sun, Christina A. Hickey, Brendan R. Harris, Horacio M. Maluf, Mai He
Esophageal parakeratosis is often seen in sloughing esophagitis, and can also be associated with fungal infection. In the absence of infection, parakeratosis is an infrequently described endoscopic and pathologic diagnosis in the pediatric population that appears to be predominantly benign. In adult esophageal biopsies, parakeratosis is a common finding, most often associated with alcohol use and smoking, and may be seen with dysplasia or carcinoma. A few case reports link diffuse parakeratosis with tylosis, mucosal hyperkeratosis syndrome, and vitamin deficiencies (9–11). The argument could be made that at least some of these cases could be re-classified as sloughing esophagitis. For example, Kayhan et al. describe “whitish strips with extensive sloughing of the esophageal mucosa” with dense layers of parakeratosis on the surface of their biopsies (10).
Optimization of nutraceutical coenzyme Q10 nanoemulsion with improved skin permeability and anti-wrinkle efficiency
Published in Drug Development and Industrial Pharmacy, 2018
Eman S. El-Leithy, Amna M. Makky, Abeer M. Khattab, Doaa G. Hussein
Figure 8(C,D) shows the histopathological examination of upper epidermal layers of untreated and treated rat skin. The untreated rat skin (Figure 8(C)) showed hyperkeratosis and parakeratosis in the epidermal layer and flatten thick horny layer. Hyperkeratosis is a thickening of stratum corneum layers caused by the accumulation of excess numbers of stratum corneum cells and disorders of keratinization because the process of desquamation is disturbed. Parakeratosis is a nucleated keratinocyte in the stratum corneum layers, which may occur due to accelerated keratinocyte turnover. Parakeratosis can be used as morphological examination character in differentiating and classifying certain inflammatory skin diseases in the epidermal layer [66]. The treated group with CoQ10 NE (F2) showed less hyperkeratosis and parakeratosis with the appearance of the thick prickle cell layer and well retained healthy cells with obvious nuclei.