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B E Schuh

Publications and source records attributed to B E Schuh.

5 recordsLinked to original sources
PubMed1976

The role of trypsin in the pre-treatment of chromosomes for Giemsa banding.

The role of trypsin in the elicitation of G-banding on human chromosomes was studied in two separate laboratories. Enzyme activity and ability of trypsin to chelate calcium were manipulated by dilution of the treatment solution, and by inhibition with diisopropylphosphofluoridate, diphenylcarbamyl chloride, or soybean trypsin inhibitor. In all cases, chromosomes were affected in proportion to the enzyme activity of the treatment solution rather than the ability of the solution to bind calcium. It is concluded that calcium chelation is not sufficient to explain G-banding trypsin, but that proteolytic activity is required.

Azure Stains↗
PubMed1975

Dynamic aspects of trypsin-giemsa banding.

The trypsin-Giemsa banding procedure was adapted so that chromosomes could be observed through the microscope during treatment and staining. Trypsin treatment resulted only in a swelling of the chromatids. Chromosome bands which appear as raised structures with interference contrast optics emerged only after staining with Giemsa. These structures remain after Giemsa destaining, suggesting that an irreversable change in chromosome structure is induced by Giemsa. Observations of the stain flow indicate that the positioning of the chromosomes has an effect on the quality of band production. These studies also revealed that bands appear in a reproducible sequence on individual chromosomes, which suggests that alterations take place at different rates along the length of the chromosomes.

Chromosomes↗
PubMed1975

Optimum pH for nuclear sex identification using quinacrine.

Preparations of quinacrine stained interphase nuclei from buccal smears and hair root sheaths were mounted in MacIlvaine's buffer at various pH's in an attempt to obtain optimum differentiation of X- and Y-chromatin. Relatively high pH (5-8) was associated with intense nuclear fluorescence. Background nuclear fluorescence decreased with lower pH's (2-4), revealing distinct granules. X-chromatin is best differentiated against this decreased background, while positive identification of Y-chromatin is more certain in the absence of confusing granules. Hence optimum pH for X-chromatin screening in quinacrine stained preparations is approximately 3.0, that for Y-chromatin screening 5.5.

Cell Nucleus↗