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Wolfgang Mann

Publications and source records attributed to Wolfgang Mann.

3 recordsLinked to original sources

An investigation of the need for sign language assessment in deaf education.

The attitudes of educators of the deaf and other professionals in deaf education concerning assessment of the use of American Sign Language (ASL) and other sign systems was investigated. A questionnaire was distributed to teachers in a residential school for the deaf in California. In addition to questions regarding the availability of sign language assessment at their schools, participants responded to items concerning their motivation to use a test for sign language measurement. Of the 100 distributed surveys, 85 were completed and returned. Results showed overwhelming agreement among respondents concerning the importance of sign language assessment, along with the need for tools that appropriately measure signing skills.

Education of Persons with Hearing Disabilities↗

Low-volume amplification on chemically structured chips using the PowerPlex16 DNA amplification kit.

In forensic DNA analysis, improvement of DNA typing technologies has always been an issue. It has been shown that DNA amplification in low volumes is a suitable way to enhance the sensitivity and efficiency of amplification. In this study, DNA amplification was performed on a flat, chemically structured glass slide in 1-microl reaction volumes from cell line DNA contents between 1,000 and 4 pg. On-chip DNA amplification reproducibly yielded full allelic profiles from as little as 32 pg of template DNA. Applicability on the simultaneous amplification of 15 short tandem repeats and of a segment of the Amelogenin gene, which are routinely used in forensic DNA analysis, is shown. The results are compared to conventional in-tube amplification carried out in 25-microl reaction volumes.

Case-Control Studies↗

Formation of higher-order nuclear Rad51 structures is functionally linked to p21 expression and protection from DNA damage-induced apoptosis.

After exposure of mammalian cells to DNA damage, the endogenous Rad51 recombination protein is concentrated in multiple discrete foci, which are thought to represent nuclear domains for recombinational DNA repair. Overexpressed Rad51 protein forms foci and higher-order nuclear structures, even in the absence of DNA damage, in cells that do not undergo DNA replication synthesis. This correlates with increased expression of the cyclin-dependent kinase (Cdk) inhibitor p21. Following DNA damage, constitutively Rad51-overexpressing cells show reduced numbers of DNA breaks and chromatid-type chromosome aberrations and a greater resistance to apoptosis. In contrast, Rad51 antisense inhibition reduces p21 protein levels and sensitizes cells to etoposide treatment. Downregulation of p21 inhibits Rad51 foci formation in both normal and Rad51-overexpressing cells. Collectively, our results show that Rad51 expression, Rad51 foci formation and p21 expression are interrelated, suggesting a functional link between mammalian Rad51 protein and p21-mediated cell cycle regulation. This mechanism may contribute to a highly effective recombinational DNA repair in cell cycle-arrested cells and protection against DNA damage-induced apoptosis.

Animals↗