Biomedical subjects

P Siman

Publications and source records attributed to P Siman.

4 recordsLinked to original sources

PubMed1992

Computer program for planning and evaluating microplate experiments.

A microcomputer program is described for planning and statistically evaluating microplate and other similar experiments. This program is written in BASIC and can be run on any PC XT/AT compatible computer under DOS. The first part of the program writes the protocol of the experiment into a disk file and sends it to a printer and also prints specifications for the addition of ingredients. The second part of the program calculates means and standard deviations of the values measured for all groups of samples. It is also possible for the program to calculate activation coefficients, coefficients of modulation and percentages of suppression for special groups. Inputting the required data can be performed manually from the keyboard or automatically from disk files.

Data Interpretation, Statistical↗

PubMed1989

Expression of MHC class II antigens is modulated by ouabain.

Ouabain enhances a modulation effect of lipopolysaccharide (LPS) on the expression of MHC class II antigens. A similar but lesser effect than that of ouabain, which increases intracellular concentration of sodium ions, has been observed when treating cells with ionophores quercetin which increases [Ca2+]i or valinomycin which increases [K+]i. These findings confirm the role of ion flux in cellular activation and differentiation. Optimal concentration of ouabain is 10(-7) M with 10 micrograms of LPS/ml for human and pig peripheral blood cells. The increase in radioactivity of mononuclear human blood cells after the binding of 125I-anti-MHC class II monoclonal antibody is at the fourth hour of cultivation with LPS and ouabain, the number of immunofluorescently positive cells rises at the twelfth hour. A similar modulation has been observed on pig kidney cell line. It can be concluded that the expression of class II antigens on the plasma membrane can be induced by cumulative effect of LPS and agents alterating ion transport.

Animals↗

PubMed1988

Alpha-fetoprotein and phagocytosis in athymic nude mice.

Alpha-fetoprotein (AFP) was found to suppress the phagocytic activity of the blood monocytes and neutrophils in vitro. The amounts of AFP detectable by immunofluorescence in the livers of nu/nu, nu/+ and +/+ mice were quite comparable, and thus could not have been responsible for the alterations in phagocytosis found in leukocytes of athymic nude mice during their ontogenetic development.

Age Factors↗

PubMed1987

Monoclonal antibodies against pig transferrin. Blocking and binding activity.

Monoclonal mouse anti-pig transferrin antibodies PTF-01, PTF-02 and PTF-03 and anti-human transferrin antibody HTF-14 detect transferrin coupled with Sepharose particles in an indirect immunofluorescence test. Only the PTF-03 antibody can be used for immunofluorescence detection of pig transferrin bound to specific receptors on the plasma membrane. The binding of iodinated pig transferrin to PK cells was studied. It could be blocked by non-labelled transferrin in excess, by pig serum or by anti-pig transferrin monoclonal antibodies. PTF-03 expressed the lowest blocking activity among the antibodies tested.

Animals↗