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Biomedical subjects

T Porstmann

Publications and source records attributed to T Porstmann.

98 records · Page 6Linked to original sources
PubMed1976

[Comparative studies on the detection of Y-chromatin in native and formalin-fixed tissue or organ material (author's transl)].

Frequency of detectable Y-bodies in interphase nuclei after mepacrin staining of paraffin embedded formalin-fixed tissue was compared with those of cryostat sections of the native material and organ smears with and without formalin fixing. In formalin fixed smears from males 42--70% of investigated cells showed the Y-body. Sections of formalin-fixed and paraffin embedded male organs demonstrated in 12--24% of their cells the typical fluorescence for the Y-chromatin. High significantly less fluorescent Y-like bodies were found in smears and sections of all proofed organs from women prepared in the same manner. Mepacrin staining in combination with investigation of Barr-bodies permits a fast determination of sex of both organ smears and sections, too.

Brain↗
PubMed1975

[Problem in the partial separation of X- and Y-carrying human spermatozoa].

The introduction of a fluorescent staining technique for identification of Y chromosome made possible the distinction of X- and Y-bearing human spermatozoa. Using this fluorescence analysis the isolation of Y- and X-bearing human spermatozoa were investigated employing two different methods for separation of spermatozoa. 1. The migration of human spermatozoa in cervical mucus obtained from women shortly before mid-cycle was studied, using an in-vitro method for horizontal sperm penetration. Basing on the progressive sperm motility in cervical mucus, a fraction rich in Y-bearing spermatozoa in the frontal zone of sperm migration was found. 2. Gradient centrifugation at different rotor speeds using a discontinous sucrose gradient has been employed for separation of human spermatozoa. A significant trend for separation of Y- and X-bearing spermatozoa was demonstrated. The results were shortly discussed.

Centrifugation, Density Gradient↗
PubMedDate not supplied

A sensitive non-isotopic assay specific for HIV-1 associated reverse transcriptase.

A sensitive non-isotopic assay for specific detection of reverse transcriptase (RT) of the human immunodeficiency virus type 1 (HIV-1) is described using 5-bromo-2'-deoxyuridine triphosphate (BrdUTP) instead of tritiated thymidine triphosphate. After the RT reaction the template primer is degraded by alkaline hydrolysis. Single-stranded poly.(BrdU) is detected in an immunoenzymometric assay using monoclonal anti-BrdU antibodies. The specificity of the assay is demonstrated by the isolation of RT from virus lysate by an insolubilised monoclonal anti-HIV-1 RT antibody prior to the RT reaction. Immunological RT binding leads to a tenfold increase in analytical sensitivity since substances inhibiting the RT reaction can be removed. This non-isotopic assay is some 30 times more sensitive than the classical radioisotopic RT assay. In terms of RT determination, however, there is a good correlation between these tests (r = 0.96). Several filtrations are no longer necessary to remove non-incorporated nucleotides. The test can be adapted to microtitre plates and hence is easy to automate.

Antibodies, Monoclonal↗