Toxic effects of selected proprietary dry eye drops on Acanthamoeba.

Amoebae of the genus Acanthamoeba are ubiquitous protists that have been isolated from many sources such as soils, water and the air. They are responsible for infections including fatal encephalitis and a severe keratitis in humans. To date, there is no satisfactorily effective therapeutic agent against this pathogen and the infections it causes are exacerbated by the existence of a resistant cyst stage produced by this amoeba. As dry eye syndrome is a risk factor for Acanthamoeba keratitis, we aimed to evaluate the anti-Acanthamoeba activity of a variety of proprietary eye drops intended to treat dry eye syndrome. From the nine eye drop formulations tested, "Systane Ultra" was determined to be the most active against all tested Acanthamoeba strains. During our investigations into the mode of action of Systane Ultra, we discovered that it decreases mitochondrial membrane potential and ATP levels, induces chromatin condensation, and increases the permeability of the plasma-membrane.

Dermoscopic features of cutaneous leishmaniasis.

BACKGROUND: Previous studies have demonstrated that dermoscopy improves accuracy in diagnosing pigmented and non-pigmented tumors. Recently, there has been increasing evidence that dermoscopy can also be useful in the diagnosis of some skin infections. OBJECTIVE: We sought to describe the dermoscopic features of cutaneous leishmaniasis. METHOD: Dermoscopic examination (using the Derm Lite FOTO, 3Gen) of 144 CL lesions in 82 patients was performed. This study was conducted in the Imam Reza and Ghaem hospitals (Mashhad, Iran) from October 2010 to September 2011. RESULTS: We observed the following dermoscopic features: generalized erythema (81.9%), white starbursts (60.4%), yellow hue (43.8%), yellow teardrop-like structures (41.7%), central ulcers (59%), hyperkeratosis (33.3%), and milia-like cysts (4.9%). We also observed vascular structures, including dotted vessels (61.1%), hairpin vessels (37.5%), linear irregular vessels (30.6%), comma-shaped vessels (29.9%), glomerular vessels (22.9%), arborizing telangiectasia (10.4%), and corkscrew vessels (4.2%). LIMITATIONS: Biopsy and pathologic evaluation were not performed due to ethical considerations. CONCLUSION: Important vascular patterns seen in melanocytic and non-melanocytic tumors were frequently observed in this infection. Dermoscopy may be a promising tool to predict the clinical course in cases of cutaneous leishmaniasis.

[Skin lesions in small mammals parasitized by Psorergates apodemi and P. dissimilis (Gheyletoidea: Psorergatidae)].

Histopathology in the sites of localization and parasiting of the mites Psorergates apodemi Fain et al., 1966 and P. dissimilis Fain et al., 1966 on the Ural field mouse Apodemus uralensis (Pallas) and the bank vole Clethrionomys glareolus (Schreber) is described. The mites affected all epidermis cell layers down to the cambium layer and caused hyperkeratosis.

Spinulosis of the face as a manifestation of demodicidosis.

We describe a 78-year-old woman with polycythaemia rubra vera who had multiple tiny follicular hyperkeratotic spicules on the cheeks. She was receiving treatment with oral hydroxyurea, but no topical agents had been applied to her face. Histopathological study demonstrated numerous Demodex folliculorum mites within dilated follicular infundibula, and we consider that the mites were playing a part in the aetiology of the skin lesions.

Host-parasite relationships in hyperkeratotic (Norwegian) scabies: pathological and immunological findings.

The dynamics of intraepidermal penetration of the scabies mite and the host's responses to the invaders have been studied in hyperkeratotic scabies. Contrary to the generally accepted view, the mites progressed not only through the stratum corneum but also into the underlying epidermis and even occasionally to the dermo-epidermal interface. Morphological evidence of reactive processes included parakeratosis surrounding the burrows, psoriasiform hyperplasia with increased basal cell labelling indices and exocytosis of mononuclear cells. 3H-Thymidine labelling indices of immunocompetent cells of the dermal infiltrate reached levels found in allergic patch test reactions and were in both cases higher than in non-immune-specific inflammatory processes. The labelling index of peripheral blood lymphocytes showed an increased ratio of B cells to T cells as compared to controls or patients with allergic contact dermatitis. Serum CIq fixation was higher than in untreated patients with common scabies. These results support our previous findings of immunological activation in host infested by the scabies mite.

Epidemic Norwegian scabies.

Norwegian scabies is an ectoparasitic infestation by Sarcoptes scabiei, characterized by hyperkeratotic lesions of the hands, feet, ears, and scalp, which contain many mites. An epidemic of Norwegian scabies involved 22 patients in a 25-patient ward of mentally and physically handicapped persons (mostly mongoloids). The pathogenesis of the prolific mite population is unclear, but either a specific immunologic deficit or the inability to effectively eliminate the mites by scratching is a plausible possibility.