Deficient N-sulfoglucosamine sulfohydrolase (SGSH) enzyme activity causes mucopolysaccharidosis (MPS) type IIIA. A fluorimetric SGSH activity assay is commonly used to examine patient cells. Here, we modified this method for brain homogenates and define the parameters for assay linearity. SGSH activity was suppressed outside of these parameters. This method will enable the accurate measurement ...

A new approach towards the rapid identification of quality binders to cucurbiturils--those that combine high affinity with high selectivity for a particular homologue--was developed. The assay exploits macrocycle-specific optical fingerprints (colorimetric or fluorimetric) of carefully selected indicators dyes. The screening of a guest library revealed known (e.g., adamantane derivatives) and n...

An alternative method for the determination of trace levels of fluoride in drinking and sea-water samples is presented. It is based on the formation of the aluminium monofluoride complex in excess of Al3+ and separation of the two species formed (AlF2+ and Al3+) in a small (5 cm long, CG2) ion exchange guard column. The final determination is accomplished by both ICP-MS specific detection and p...

We studied the intracellular pH of Vero cells parasitised by Trypanosoma cruzi, using different methods: fluorimetric measurement after labelling the cells with the pH-sensitive intracellular fluorescent dye 2',7',-bis-(2-carboxyethyl)-5-(and-6)-carboxyfluorescein, acetoxymethyl ester; flow cytometry; and image analysis after staining the cells with neutral-red vital stain. The results show tha...

An easy fluorimetric assay for measuring D-amino acid oxidase (DAAO) activity by using one of the D-amino acids--D-kynurenine (D-KYN)--as a substrate was applied to assess DAAO activity in the cerebrum, cerebellum, and brainstem of Sprague-Dawley (SD) male rats. In this assay, DAAO produces kynurenic acid (KYNA) from D-KYN, and the fluorescence originating from KYNA can then be used to evaluate...

We describe biophysical and ultrastructural differences in genome release from adeno-associated virus (AAV) capsids packaging wild-type DNA, recombinant single-stranded DNA (ssDNA), or dimeric, self-complementary DNA (scDNA) genomes. Atomic force microscopy and electron microscopy (EM) revealed that AAV particles release packaged genomes and undergo marked changes in capsid morphology upon heat...

Studies in humans indicate genetic effects on the ventilatory response to hypoxia, but the site of these effects is unknown. The present study explores the question of whether there are genetically directed effects on the intrinsic hypoxic chemosensitivity of the carotid body. The approach was to study these responses in two inbred rat strains [spontaneously hypertensive rats (SHR) and Fischer ...

A broad series of homochiral perylene bisimide (PBI) dyes were synthesized that are appended with amino acids and cationic side chains at the imide positions. Self-assembly behavior of these ionic PBIs has been studied in aqueous media by UV/Vis spectroscopy, revealing formation of excitonically coupled H-type aggregates. The interactions of these ionic PBIs with different ds-DNA and ds-RNA hav...

We demonstrate here for the first time that a guanidiniocarbonyl-pyrrole (GCP) unit can be applied for the fine recognition of single stranded RNA sequences-an intuitively unexpected result since so far binding of the GCP unit to ds-DNA or ds-RNA relied strongly on minor or major groove interactions, as shown in previous work. Two novel nucleobase-GCP isosteric conjugates differing in the flexi...

New simple and sensitive spectrophotometric and fluorimetric methods have been developed for the determination of prazosin hydrochloride (PRZ) in its active pharmaceutical ingredient (API) and drug product. The spectrophotometric method (Method I) is based on formation of a binary complex with rose Bengal (RB) at 572 nm. The absorbance-concentration plot is rectilinear over the range 2.5 25 μg/...