Of 32 studies comparing plasma norepinephrine concentrations in hypertensive and normotensive groups, 28 (88%) reported higher levels in the hypertensive group. However, only 13 (41%) of the studies reported statistically significant hypertensive-nonnotensive differences in norepinephrine, leading the present attempt to identify factors differentiating "positive" studies (those reporting signif...

The effects of divalent cations on voltage-activated Ca2+ channels and depolarization-evoked cytoplasmic [Ca2+] elevations were studied in pyramidal neurones isolated from the dorsal cochlear nucleus of the rat. Ca2+ currents were recorded using the whole-cell configuration of the patch-clamp technique. 10 micromol x l(-1) Cd2+ exerted a greater blocking effect on the high-voltage activated (HV...

Clinical isolates of Staphylococcus aureus carry various antiseptic and disinfectant resistance determinants (qac genes) on a variety of plasmids. The biochemistry and specificity of these resistance genes in S. aureus is the subject of this report. The qac genes were separated into two families on the basis of resistance profiles and DNA homology. Isotopic and fluorimetric assays demonstrated ...

The present review article presents and discusses automated sequential injection (SI) based methods for the determination of pharmaceutically and biologically important thiols, namely cysteine, N-acetylcysteine, penicillamine, glutathione and captopril. The review intends to cover a range of ten years of published research on this topic (2000 – 2009). The methods are classified according to the...

It is shown by sedimentation velocity and polarization of fluorescence measurements that yeast enolase in solution becomes more compact on addition of magnesium. This is associated with changes in absorption, fluorescence emission, and fluorescence-polarization spectra, as well as in the thermal stability of the enzyme. Evidence is presented that this structural change is produced by the bindin...

Aldehyde dehydrogenase (ALDH) is known to be susceptible to oxidation, and its assays require stabilization of the enzyme by thiols. Application of the fluorimetric method to assay the ALDH activity in human saliva demonstrated significant differences between procedures utilizing glutathione (GSH) and dithiothreitol (DTT) as stabilizing agents. It has been recently shown that average aldehyde d...

A fluorimetric immunoassay has been used to assess reactivity of rheumatoid factor (RF) with both histone proteins and other basic polycations (poly-L-lysine, poly-L-ornithine, and protamine) bound to an immobilised tyrosine-glutamic acid polyanionic copolymer. Isolated RF preparations can bind to histone proteins in this assay, notably to H3 and H4 histones, and this activity was always masked...

Ethidium bromide (EtBr) is the most widely used fluorescent dye in nucleic acid gel electrophoresis since decades. However it has been essentially forgotten in DNA quantification by spectrofluorimetry. While investigating sensitivity and dynamic range of available fluorochromes, we found that EtBr permits much more sensitive fluorimetric measurements than previously thought. We report here a re...

Uranyl nitrate inhibited root growth of Allium cepa at > or = 25 microM concentration. Fluorimetric analysis of metal uptake indicated the entry and accumulation of uranium into the root cell. Uranyl nitrate was neither clastogenic nor aneugenic as it failed to induce micronuclei significantly, but between 25 and 100 microM concentration, it increased significantly the frequency of sister chrom...