Glutamate is a mediator of neurotoxicity in secretions of activated HIV-1-infected macrophages.

We sought to identify neurotoxin(s) secreted by HIV-1-infected mononuclear phagocytes that could contribute to the pathophysiology of HIV-1-associated dementia (HAD). Neurotoxic factors were characterized in batches of conditioned media (CM) from human monocyte-derived macrophages (MDM) infected with HIV-1(ADA) and/or activated with lipopolysaccharide (LPS). All of the neurotoxicity was: present in the <3000-Da fraction; blocked by 5 microM MK801; and not trypsin sensitive or extractable into polar organic solvents. Glutamate measured in CM accounted for all neurotoxic effects observed from HIV/LPS CM in astrocyte-poor neuronal cultures and may contribute to the pathophysiology of HIV-1-associated dementia.

Capillary electrophoresis-based immunoassays.

This review covers the progress and developments in the field of capillary electrophoresis immunoassay (CEIA) over the past three years. Because many excellent descriptions of the principles of these methods are available (e.g., in the reviews listed in this article), no elementary introduction is given to the field of immunoassays (IAs) or CEIAs. This report focuses exclusively on experimental results, dividing the CEIA papers into the categories of direct, indirect, and microchip electrophoretic immunoassays. In the last section, a brief summary of the current status of the CEIA field is presented.

Capillary electrophoresis for the detection of known point mutations by single-nucleotide primer extension and laser-induced fluorescence detection.

Capillary electrophoresis (CE) with laser-induced fluorescence (LIF) was used to detect known point mutations using the method of single-nucleotide primer extension (SNuPE). Three different point mutations in human mitochondrial DNA associated with Leber's hereditary optic neuropathy (LHON) were detected by annealing a primer immediately 5' to the mutation on the template and extending the primer by one fluorescently labeled dideoxy terminator complementary to the mutation. By using two or more differently labeled terminators, both the mutant and wild type could be simultaneously detected. The advantages of using CE-LIF for detecting SNuPE reactions include speed and ease of analysis, absence of radioactivity, and potential for automation.

Characterization and performance of a neutral hydrophilic coating for the capillary electrophoretic separation of biopolymers.

Polyvinylmethylsiloxanediol (50% vinyl) was synthesized and combined with a cross-linker for static coating onto fused-silica columns. After cross-linking and binding to the surface, linear polyacrylamide was grafted to the double bonds of the siloxanediol; subsequently, this linear polymer matrix was cross-linked with formaldehyde. The grafted neutral polymeric layer provided suppression of electroosmotic flow and minimized adsorption. This combination yielded successful open tube and polymer network separations of proteins, peptides and DNA molecules. Very high efficiencies (ca. 1 x 10(6) plates/m) were achieved for open tube protein separations, and hundreds of consecutive runs were performed with minimal change in migration times.