Comparison of actual psoriasis surface area and the psoriasis area and severity index by the human eye and machine vision methods in following the treatment of psoriasis.

The lack of a quantitative method for assessing psoriasis severity poses a problem for quality control in dermatology. Quantitative estimation of involved surface area is important, as in the psoriasis area and severity index (PASI), but the reliability of many methods is poor. The purpose of this study was to assess the involved surface area of 15 psoriasis patients before and after different anti-psoriasis treatments using the human eye method and a computer image analysis (CIA) system based on colour segmentation. The human eye assessments were compared with the results of the CIA system and the resulting effects on the PASI score were also compared. The human eye estimates were higher than those obtained by the CIA method and, as a consequence, the values of the PASI by the human eye method were also higher than those by CIA. The human eye estimates differed most in cases where the PASI was under 15. The changes in the PASI by the human eye method before and after treatments differed significantly from those by CIA. The CIA system offers a possibility to quantify actual surface in patients with psoriasis, and will be an alternative for developing quality control when evaluating different treatment efficacies.

alpha-Galactosidases of Penicillium simplicissimum: production, purification and characterization of the gene encoding AGLI.

Production of extracellular a-galactosidases by the filamentous fungus Penicillium simplicissimum (previously P. janthinellum) VTT-D-78090 was studied on different carbon sources. Steam-exploded oat husks were chosen as the best carbon source for enzyme production. Three a-galactosidases (AGL) were purified from the culture filtrate using ion-exchange chromatography, hydrophobic interaction chromatography and gel filtration. The isoelectric points of AGLI, AGLII and AGLIII were 5.2, 4.4 and 7.0, and the molecular masses as determined by SDS/PAGE were 61, 84 and 61 kDa, respectively. All enzymes were glycosylated. The optimum pH for the activity of AGLI and AGLIII was between 3.0 and 4.5 and that of AGLII was between 4.0 and 5.0. AGLII was more stable and more resistant to product inhibition by galactose than the other two enzymes. AGLI and AGLIII were also inhibited by p-nitrophenol-a-D-galactopyranoside, the substrate used for enzyme activity assay. The gene encoding AGLI was cloned and sequenced. The gene, agl1, encodes 435 amino acids including the signal sequence. It showed similarity with the other a-galactosidases belonging to the glycosyl hydrolase family 27. The N-terminal amino acid sequence of AGLIII was also similar to the sequences of other members of family 27, whereas the N-terminus of AGLII was completely different from the sequences of other reported hydrolases.

Genetic and biochemical characterization of the Trichoderma reesei hydrophobin HFBI.

The hfb1 gene of the filamentous fungus Trichoderma reesei, previously cloned as a gene which was abundantly expressed when the fungus was grown on glucose-containing medium, was shown to encode a novel fungal hydrophobin. The encoded 97-amino-acid protein is cysteine-rich and has a typical signal sequence for secretion. Signal-sequence cleavage and putative proteolytic processing results in the mature HFBI protein of 75 amino acids. Antibodies raised against the HFBI protein expressed in Escherichia coli detected the T. reesei HFBI protein in the fungal cell wall and in the culture medium of submerged glucose-containing cultures. The identity of HFBI was verified by N-terminal and peptide sequencing of proteins purified both from the cell wall and culture medium. In the cell wall most of the HFBI formed SDS-insoluble complexes that could be extracted with trifluoroacetic acid. Bubbling or freezing of the culture medium caused HFBI to form aggregates that coprecipitated with a yellow pigment produced by the fungus.

Isolation of Trichoderma reesei genes highly expressed on glucose-containing media: characterization of the tef1 gene encoding translation elongation factor 1 alpha.

Genes that are highly expressed on glucose-containing media were isolated from the filamentous fungus, Trichoderma reesei. A cDNA bank was prepared from glucose-grown fungus, the bank was screened with the same cDNA as a probe, and clones giving the strongest signal were isolated. This resulted in the isolation of previously uncharacterized genes. Five of the genes, representing the most abundant transcripts, corresponded to 1-3% of the total mRNA population and were clearly more highly expressed than the phosphoglycerate kinase-encoding gene (pgk1) of T. reesei. Based on sequence homology, one of the genes was identified as tef1, encoding translation elongation factor 1 alpha (TEF). The T. reesei TEF is most related to the Mucor racemosus TEF3, showing an overall amino acid similarity of 85%. Interestingly, an exon of only 2 bp seems to be present in T. reesei tef1, comprising the first 2 bp of the Gly15 codon.