Onychomycosis in patients with psoriasis--a multicentre study.

1-3% of human population is affected by psoriasis. Nail disorders are reported in 10-80% of patients with psoriasis. Nail deformations vary according to their degree of severity but are mainly represented by pitting, Beau's lines, hyperkeratosis, onycholysis, leuconychia or oil drops. Onychomycosis is a fungal infection of the nails, caused by dermatophytes, yeast and moulds. In this study, 228 patients with psoriasis aged between 18 and 72 were examined (48 - from Plovdiv, Bulgaria; 145 - from Pleven, Bulgaria and 35 - from Thessaloniki, Greece); 145 of them were male and 83 of them were female. The examination of the nail material was performed via direct microscopy with 20% KOH and nail samples plated out on Sabouraud agar methodology. The severity of the nail disorders was determined according to the Nail Psoriasis Severity Index (NAPSI). Positive mycological cultures were obtained from 62% of the patients with psoriasis (52%- Plovdiv, Bulgaria; 70%- Pleven, Bulgaria and 43%- Thessaloniki, Greece). In 67% of the cases, the infection was caused by dermatophytes, in 24% by yeast, in 6% by moulds and in 3% by a combination of causes. All patients with psoriasis were identified with high levels of NAPSI, whereas the ones with isolated Candida had even higher levels. Seventeen percentage of the patients have been treated with methotrexate, 6% have been diagnosed with diabetes and 22% have been reported with onychomycosis and tinea pedis within the family. An increased prevalence of onychomycosis among the patients with psoriasis was found. Dystrophic nails in psoriasis patients are more predisposed to fungal infections. The mycological examination of all psoriasis patients with nail deformations is considered obligatory because of the great number of psoriasis patients diagnosed with onychomycosis.

Interlayer stacking disorder in zeolite beta family: a Raman spectroscopic study.

Raman spectroscopy has been applied to series of BEA- and BEC-type samples differing from each other in size, Si/Al ratio and polymorph percentage in order to analyse the effect of interlayer stacking arrangements on the vibrational modes of zeolite beta. The Raman peaks observed in the spectral range 250-550 cm-1 were assigned to the rings building the basic (001)-layer and to those linking the adjacent layers in zeolite beta. It is shown that the intensity ratio rho between the Raman signals at 314 and 343 cm-1 is most sensitive to the degree of periodicity faults along the c direction. A larger value of rho indicates a larger size of polymorph stacking sequence, i.e. improvement of the stacking faultlessness. The interlayer stacking disorder and the degree of connectivity point defects are higher in nanosized zeolite beta than in micron-sized crystals. The Al content influences the concentration of defected SiOH groups, but is less important for the interlayer stacking sequences in colloidal zeolite beta.

Mechanism of zeolite A nanocrystal growth from colloids at room temperature.

The formation and growth of crystal nuclei of zeolite A from clear solutions at room temperature were studied with low-dose, high-resolution transmission electron microscopy in field emission mode and with in situ dynamic light scattering. Single zeolite A crystals nucleated in amorphous gel particles of 40 to 80 nanometers within 3 days at room temperature. The resulting nanoscale single crystals (10 to 30 nanometers) were embedded in the amorphous gel particles. The gel particles were consumed during further crystal growth at room temperature, forming a colloidal suspension of zeolite A nanocrystals of 40 to 80 nanometers. On heating this suspension at 80 degrees C, solution-mediated transport resulted in additional substantial crystal growth.