Molecular characterization of cyclophilin protein gene in skin normal microflora: malassezia furfur

Malassezia are dimorphic, lipid-dependent yeasts, which are responsible for causing several cutaneous and systemic conditions. Although cyclophilins [CyPs] are highly conserved cytosolic proteins that catalyze the peptidyl-prolyl cis-trans isomerazation reaction before protein folding process, it has been suggestive of an allergen in a few numbers of fungi such as Aspergillus fumigatus and Malassezia species. Allergenic cyclophilins are IgE-binding components, which have been characterized in other species of Malassezia; and are considered as Mala s 6 in Malassezia sympodialis. In the present study we tried to identify the molecular characterization of cyclophilin gene in M. furfur. Pairs of oligonucleotide primers were designed from highly conserved regions of the gene counterparts in other fungi. The primers were then applied to amplify the primer-specific DNA fragment. Afterward, PCR product fragments were sequenced to be used in further analysis. About 573 nucleotides, encoding a polypeptide of 190 amino acids, have been sequenced. Sequence comparison was performed in Gene Bank, both for the nucleotides and their deduced amino acid sequence. It revealed a significant homology with cyclophilin genes and proteins of other eukaryotic cells. The amino acid sequence of the encoded protein was about 86% identical to the sequence of cyclophilin protein from other fungi. The molecular characterization of cyclophilin gene may open the way to disclosure of the functional characteristics of cyclophilin and is a fundamental step for understanding the molecular basis of its pathogenesis in AEDS disease

[ effect of different surface treatments of stainless steel crown and different bonding agents on shear bond strength of direct composite resin veneer]

Stainless steel crown [SSC] is the most durable and reliable restoration for primary teeth with extensive caries but its metalic appearance has always been a matter of concern. With advances in restorative materials and metal bonding processes, composite veneer has enhanced esthetics of these crowns in clinic. The aim of this study was to evaluate the shear bond strength of SSC to composite resin using different surface treatments and adhesives. In this experimental study, 90 stainless steel crowns were selected. They were mounted in molds and divided into 3 groups of 30 each [S, E and F]. In group S [sandblast], buccal surfaces were sandblasted for 5 seconds. In group E [etch] acidic gel was applied for 5 minutes and in group F [fissure bur] surface roughness was created by fissure diamond bur. Each group was divided into 3 subgroups [SB, AB, P] based on different adhesives: Single Bond, All Bond2 and Panavia F. Composite was then bonded to specimens. Cases were incubated in 100% humidity at 37°C for 24 hours. Shear bond strength was measured by Zwick machine with crosshead speed of 0.5 mm/min. Data were analyzed by ANOVA test with p<0.05 as the limit of significance. There was no statistical interaction between surface treatment and adhesive type [P>0.05] so the two variables were studied separately. No significant difference was observed in mean shear bond strength of composite among the three kinds of adhesives [P>0.05]. Similar results were obtained regarding surface treatments [P>0.05]. Based on the results of this study, treating the SSC surface with bur and using single bond adhesive and composite can be used successfully to obtain esthetic results in pediatric restorative treatments

Molecular characterization of GTP binding protein gene in dermatophyte pathogen trichophyton rubrum

Trichophyton rubrum [T. rubrum] is an anthropophilic dermatophyte that is distributed worldwide and causes common cutaneous disease such as mycosis. Although several properties of this fungus have been investigated so far, however a few studies were carried out in the field of molecular biology of this fungus. In the present study we tried to identify its molecular characterization of the goanosin three phosphat [GTP] binding protein gene. Pairs of 21 nt primers were designed from highly conserved regions of the gene in other fungi. The primers were utilized in PCR by using isolated genomic DNA tem-plate as well as cytoplasmic RNA of T. rubrum and the PCR and RT-PCR fragments were then sequenced. About 645 nucleotides have been sequenced which encodes a polypeptide with 214 amino acids. Nucleotide sequence comparison in gene data banks [NCBI, NIH] for both the DNA and its deduced amino acid sequence revealed significant homology with GTP binding protein genes and proteins of other eukaryotic cells. The amino acid sequence of the encoded protein was about 64% identical to the sequence of GTP binding protein from other fungi. In summary, we have cloned the first GTP binding protein of dermatophytes and characterized it as a member of this gene family in other eukaryotic cells

Molecular characterization of subunit G of the vacuolar ATPase in pathogen dermatophyte trichophyton rubrum

Trichophyton rubrum is an anthropophilic fungus causing up to 90% of chronic cases of dermatophytosis. Several properties of this fungus have been investigated so far. However, a few studies were carried out in the field of molecular biology of this fungus. In the present study, we tried to identify the subunit G of its vacuolar ATPase [V-ATPase]. Pairs of 21 nt primers were designed from highly conserved regions of the V-ATPase subunit G genes in other fungi. Mentioned primers were utilized in PCR using isolated genomic DNA template as well as cytoplasmic RNA of T.rubrum and the PCR and RT-PCR fragments were then sequenced. About 469 nucleotides were sequenced which encoded a polypeptide with 119 amino acids. Nucleotide sequence comparison in gene data banks [NCBI, NIH] for both the DNA and its deduced amino acid sequence revealed significant homology with V-ATPase subunit G genes and proteins of other eukaryotic cells. The amino acid sequence of the encoded protein was about 84% identical to the sequence of V-ATPase subunit G from other fungi. In summary, we have cloned the first V-ATPase subunit G of dermatophytes and characterized it as a member of this gene family in other eukaryotic cells