PubMed HealthSearch

PubMed · 46862

The influence of fixation on staining of glycosaminoglycans in glial cells.

Abstract

Cytoplasmic staining of glial cells by Alcian blue in 0.40 M magnesium chloride can be demonstrated in sections of brain tissue fixed in formol-acetic acid and in Bouin's solution. Phosphate-buffered aldehyde fixatives, whether at neutral or low pH, fail to preserve stainable material.

Explore related subjects

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

M Lai, I A Lampert, P D Lewis. 1975. The influence of fixation on staining of glycosaminoglycans in glial cells.. https://doi.org/10.1007/bf00497691

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related citations

Phenylglyoxal modification of cardiac myosin S-1. Evidence for essential arginine residues at the active site.

The role of arginine residues in the catalytic activity of cardiac myosin subfragment-1 (S-1) was investigated by selective modification with phenylglyoxal. Incorporation of about 2.8 mol of phenylglyoxal/mol of S-1 decreased Ca2+-ATPase activity about 50%. Gelation of the protein occurred at about 70% inactivation; however, extrapolation to complete inactivation indicated that loss of activity correlated with modification of about 4 arginyls/mol. Partial inactivation of S-1 with phenylglyoxal also decreased MgADP binding markedly. When S-1 was modified in the presence of 5 mM MgADP, only 2 arginyls/mol were blocked and there was almost complete protection against loss of Ca2+-ATPase activity and ability to bind MgADP. Similar protection against inactivation by phenylglyoxal was obtained with MgATP or sodium pyrophosphate, but not with MgAMP or magnesium adenosine. These results suggest that 2 arginyls/myosin head are important for enzymatic activity, possibly serving as attachment points between enzyme and substrate. These essential arginyls were localized to a 17,000-dalton cyanogen bromide peptide from the heavy chain fragment of S-1.

Aldehydes

Secondary structure of the 5' end of bacteriophage MS2 RNA Methoxyamine and kethoxal modification.

To refine the secondary structure model of the 5' end of the bacteriophage MS2 genome, 32P-labeled MS2 RNA was partially digested with T1 RNase or with Cm-RNase and the 5'-end fragment was isolated, renatured and submitted to treatment with methoxyamine or kethoxal. The resulting modified RNA was digested with T1 RNase and the products were separated by minifingerprinting. Methoxyamine-induced modification of exposed cytidines was detected by differential mobility of modified oligonucleotides, while kethoxal-induced alteration of exposed guanosines was monitored by resistance to T1 ribonuclease digestion. The positions of the modified residues are discussed in terms of an improved secondary structure model proposed for the 5' end of the viral RNA. The structure itself is discussed in relation to sequence conservation and biological function.

Aldehydes