Seminiferous vessels stained for cytokeratin 18 without (upper) and with (lower) antigen retrieval Chemically fixing tissue sections may lock in a good result for the world to see, but it can complicate subsequent immunohistochemical staining by masking relevant antigens. A process known as antigen retrieval can restore the antigenicity of proteins altered by fixation and improve immunohistochemical detection. It can also reduce background staining, which makes it an important step in developing

Bayer's QuantiGene technology Advances in cell-based assay design are inspiring new approaches for screening compounds during drug discovery. Bayer Corp.'s QuantiGene assay system is a cell-based assay for the direct quantitation of mRNA from lysed cells or whole tissue. The system uses branched DNA (bDNA) technology for signal amplification and is designed for a 96-well microplate format. In addition, Bayer provides ProbeDesigner™ software for designing oligonucleotide probes used in th

Pool Your Resources Stratagene is offering a 13-30 percent discount on master membranes for its HUCL (Human Universal cDNA Library) Array Cloning System until July 31, 2000. The HUCL Array Cloning System is a two-step gene identification system: The first screen is performed on multiple master membranes, each containing pooled clones. Then, the clone of interest is identified from a secondary membrane or microplate containing the individual clones from a particular pool. When ordering the HUCL

Advances in sequencing technology now make it possible to obtain the sequence of entire genomes. SpectruMedix Corp. of State College, Pa., continues this trend with the introduction of the SCE9610, an automated 96-capillary instrument for high-throughput DNA sequencing, fragment analysis, and genotyping. The science behind the SCE9610 is based on award-winning technology developed by Edward Yeung at the Ames Laboratory at Iowa State University.1 The SCE9610 uses a charge-coupled device (CCD) cam

Quite a Stir Thermolyne's MiniStirrer Thermolyne's new personal MiniStirrer™, available in standard, digital, and portable DC models, offers powerful stirring ability at a compact size and price. The MiniStirrer can stir 1 l of liquid up to 2,000 rpm and features a Hytrel® base and chemically resistant nylon top. Its stylish design makes it an attractive as well as practical addition to any fume hood, glove box, or lab bench. List prices for the standard, digital, and portable models

Novagen's pTriEx-1 vector contains bacterial, insect, and mammalian promoters. When studying protein function, researchers must often express a protein of interest in different systems for different applications. High-yield requirements might call for cloning of the target gene into an Escherichia coli expression vector, whereas subsequent activity studies might benefit from insect or mammalian cell expression. Obtaining the perfect balance between yield and activity may also inspire testing of

Erase RNase To help researchers working with RNA fight the war against RNase contamination, Ambion now offers its RNaseZap® solution in an easy-to-use towel format. RNaseZap Wipes remove RNase contamination from glass and plastic surfaces immediately on contact. The towels leave no residues that inhibit subsequent enzymatic reactions. RNaseZap Wipes are available in 100-sheet pop-up dispensers for $37.00. Ambion, (800) 888-8804, www.ambion.com Well Done Owl's Multiload Comb Loading each i

Transposons, mobile DNA elements found in the genomes of prokaryotic and eukaryotic organisms, move randomly from one site in a chromosome to another using a process catalyzed by transposases. This process, called transposition, occurs naturally but infrequently in cells as a means of genetic change. For many years scientists have used transposons for genetic research. A new system, combining Tn5 transposase and a Tn5-derived transposon to form a stable synaptic complex, forms the basis of EZ::

Autogen separates signal from background on microarray images. Microarray technology is revolutionizing drug discovery, genetic diagnostics, and genomic research. However, processing and analyzing images can be problematic. Semiautomated processing tools such as BioDiscovery's ImaGene™ now enable scientists to process images more efficiently and quickly. Given the array boundaries, this technology locates each spot, and graphic user interface tools facilitate manual correction of misidenti

In the past, researchers seeking to quantify or detect small amounts of DNA in a sample have relied on techniques such as ultraviolet spectroscopy and agarose gels. While these techniques continue to be useful for a variety of molecular biology applications, they are highly sensitive to contamination by proteins, buffers, and detergents. In addition, these techniques are best suited to the analysis of microgram amounts of DNA. In September of 1999, Promega introduced the DNAQuant DNA Quantitati