A. A. Markaryan

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Extracellular proteases have been suggested to be virulence factors in invasive aspergillosis. Since serine protease gene-disrupted mutants retain virulence, other proteases are suspected to be also involved in the degradation of lung structural material. An elastinolytic neutral metalloprotease was purified 320-fold from the extracellular fluid of(More)
The function of the long propeptides of fungal proteinases is not known. Aspergillus fumigatus produces a 33-kDa serine proteinase of the subtilisin family and a 42-kDa metalloproteinase of the thermolysin family. These extracellular enzymes are synthesized as preproenzymes containing large amino-terminal propeptides. Recombinant propeptides were produced(More)
OBJECTIVES/HYPOTHESIS This study was conducted to evaluate the association between the mitochondrial DNA (mtDNA) common deletion (CD) level in cochlear tissue and the severity of hearing loss in individuals with presbycusis. STUDY DESIGN Nineteen individuals with presbycusis, ranging from 60 to 87 years of age, who met strict audiometric criteria were(More)
An extracellular elastinolytic metalloproteinase, purified from Aspergillus fumigatus isolated from an aspergillosis patient/and an internal peptide derived from it were subjected to N-terminal sequencing. Oligonucleotide primers based on these sequences were used to PCR amplify a segment of the metalloproteinase cDNA, which was used as a probe to isolate(More)
Large-scale deletions of mitochondrial DNA (mtDNA) have been associated with aging and disease in post-mitotic tissues. These post-mitotic tissues, including skeletal muscle, heart and brain, are heavily dependent on intact functional mitochondria. The cochlear tissues are known to contain an abundance of mitochondria. This observation stimulated a search(More)
Plasma complement factor H (Cfh) is a potent complement regulator, whereas Cfh on the surface of rodent platelets is responsible for immune complex processing. For dissection between the two, bone marrow chimeras between Cfh-deficient (Cfh(-/-)) and wild-type C57BL/6 mice were created. Platelet Cfh protein was tracked with the Cfh status of the bone marrow(More)
Intestinal ischemia-reperfusion (IR) injury is initiated when natural IgM Abs recognize neo-epitopes that are revealed on ischemic cells. The target molecules and mechanisms whereby these neo-epitopes become accessible to recognition are not well understood. Proposing that isolated intestinal epithelial cells (IEC) may carry IR-related neo-epitopes, we used(More)
CONCLUSION The results of this study demonstrate that proteomic analysis can be successfully performed on formalin-fixed celloidin-embedded (FFCE) archival human cochlear tissues. OBJECTIVE To investigate the feasibility of analyzing protein expression in archival cochlear tissues. MATERIAL AND METHODS A new methodology, referred to as Liquid(More)
The large archival human temporal bone collections of the world have been fixed in formalin and embedded in celloidin. These treatments have created challenges to the use of contemporary probes, which are routinely used in the evaluation of fresh and frozen tissues, for the analysis of archival temporal bone tissues. Formalin alters the configuration of(More)
CONCLUSIONS This study suggests that cytochrome c oxidase subunit 3 (COX 3) expression is diminished in spiral ganglion cells from individuals with presbycusis. In addition to the mitochondrial DNA (mtDNA) common deletion (CD), other deletions involving the mtDNA major arc contribute to the observed deficit in COX 3 expression. OBJECTIVES To assess COX 3(More)