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The virulence properties of Candida spp. presents in landfill leachate still unknown until today and they constitutes a serious source of potential danger for humans. We investigate the antifungal susceptibility, production of hydrolytic enzymes and biofilm formation on polystyrene as well as glass in Candida spp. strains isolated from a landfill leachate treatment station in Borj Chakir (Tunisia). 37 yeast strains were isolated belonging to the following species: C. robusta, C. lusitaniae, C. tropicalis, C. krusei. Most isolated yeast strains were resistant to Amphotericin B, produced several hydrolytic enzymes (67.56% produced phospholipase, 86.04% protease, 64.86% esterase) and most of them are able to degrade hemoglobin. All assayed Candida strains have been able to form biofilm on polystyrene depending on the species and strain of Candida. Landfills receiving clinical waste are a potential source of Candida ssp. strains with several virulence properties which allow them to survive in different aquatic biotopes., (Copyright © 2018. Published by Elsevier Ltd.)

Diagnosis of lysosomal storage disorders (LSDs) is mainly based on specific enzyme assays in leucocytes. Dried blood spots have also been used as sample for the enzyme assays. However, some lysosomal enzymes such as heparan-N-sulfamidase (HNS) and others cannot be assayed by this material. We developed an assay for HNS using dried leukocytes impregnated in filter paper (DLFP) as source of enzyme, and the results allowed the correct identification of Mucopolisaccharidosis IIIA. From this proof of concept we predict that the assay of lysosomal enzymes in DLFP samples, which still needs further development, could be a useful tool for the diagnosis of LSDs, especially in regions where transportation of liquid blood samples in appropriate conditions for long distances and/or across country borders is challenging., (© 2013 Elsevier Inc. All rights reserved.)

Mucopolysaccharidosis type IIIA (MPS-IIIA) is an autosomal recessive lysosomal storage disorder caused by the deficiency of heparan-N-sulfamidase (NS; EC 3.10.1.1), resulting in defective degradation and subsequent storage of heparan sulfate and leading to a clinical phenotype known as Sanfilippo syndrome. A sensitive and specific monoclonal/polyclonal-based immunoquantification assay has enabled the determination of NS protein, down to approximately 3 pg NS protein, in cultured fibroblasts from control and MPS-IIIA patients. Cultured skin fibroblasts from 15 normal controls contained 11.9 to 105 ng of NS protein/mg extracted cell protein, whereas NS protein ranged from "none detected" to 11 ng/mg in fibroblasts from 35 MPS-IIIA patients. A relationship between genotype/phenotype and amount of NS protein present in these MPS-IIIA fibroblasts was established. Immunoquantification, in combination with a specific and highly sensitive tetrasaccharide-based assay of NS activity, enabled the determination of residual specific NS activity in these fibroblasts. Specific NS activity ranged from 28 to 1289 nmol/min/mg NS protein for MPS-IIIA patients, compared to 870 nmol/min/mg of recombinant human NS. It is proposed that this immunoquantification method, in conjunction with the specific NS activity assay, may be used to predict clinical severity in MPS-IIIA patients, allowing for the selection of individuals best suited for gene- and enzyme-replacement therapy when these methods become available. Also proposed is that an enzyme-replacement therapy achieving a correction of approximately 10% of normal NS activity is required to avoid the onset of a Sanfilippo clinical phenotype., (Copyright 2001 Academic Press.)

Fluorescence histochemical techniques are described to localize intracellular enzyme and tubercle bacilli in alveolar macrophages obtained from infected guinea pigs. The study demonstrated a double-staining technique using 4-methylumbelliferyl substrates for enzyme localization followed by auramine-O staining for intracellular tubercle bacilli. Upon enzyme substrate reaction, released 4-MU remains retained inside the cell and gives a green fluorescence, whereas tubercle bacilli give a yellow fluorescence of auramine staining. The technique is useful where a correlation of enzyme activity vs a presence of bacilli in vivo is required at the single cell level.