RESUMEN
In light of the different reproductive roles of men and women, our objective was to ascertain whether men and women attach different significance to genetic, as distinct from gestational, ties to offspring. Surveys returned by 106 men and women of reproductive age in the general clinic waiting area of the University of Chicago Health Service showed that 71.1% of women and 62.9% of men would seek medical assistance if necessary to have a biologically related child. When women were asked whether they would choose the genetic tie or the gestational tie if both were not possible, 48.6% chose the genetic tie, and 51.4% chose the gestational tie. When men were asked which relationship they preferred for their partner, 73.5% chose the genetic tie, and 26.5% chose the gestational tie. Neither marital status nor experience of child-birth (for oneself or one's partner) were predictive of preferences. Our data suggest that gender differences as well as individual differences need to be addressed in counseling individuals and couples.
Asunto(s)
Actitud , Padre/psicología , Madres/psicología , Técnicas Reproductivas , Adulto , Femenino , Identidad de Género , Humanos , Masculino , Embarazo , Encuestas y CuestionariosRESUMEN
Competition binding and UV melting studies of a DNA model system consisting of three, four or five mutually complementary oligonucleotides demonstrate that unpaired bases at the branch point stabilize three- and five-way junction loops but destabilize four-way junctions. The inclusion of unpaired nucleotides permits the assembly of five-way DNA junction complexes (5WJ) having as few as seven basepairs per arm from five mutually complementary oligonucleotides. Previous work showed that 5WJ, having eight basepairs per arm but lacking unpaired bases, could not be assembled [Wang, Y.L., Mueller, J.E., Kemper, B. and Seeman, N.C. (1991) Biochemistry, 30, 5667-5674]. Competition binding experiments demonstrate that four-way junctions (4WJ) are more stable than three-way junctions (3WJ), when no unpaired bases are included at the branch point, but less stable when unpaired bases are present at the junction. 5WJ complexes are in all cases less stable than 4WJ or 3WJ complexes. UV melting curves confirm the relative stabilities of these junctions. These results provide qualitative guidelines for improving the way in which multi-helix junction loops are handled in secondary structure prediction programs, especially for single-stranded nucleic acids having primary sequences that can form alternative structures comprising different types of junctions.
Asunto(s)
Composición de Base , ADN/química , Conformación de Ácido Nucleico , Nucleótidos/química , Autorradiografía , Secuencia de Bases , Unión Competitiva , Estabilidad de Medicamentos , Electroforesis en Gel de Poliacrilamida , Datos de Secuencia Molecular , Espectrofotometría , Rayos UltravioletaRESUMEN
We have shown previously that dystrophin is a component of postsynaptic membranes in Torpedo electric organ and is localized at mammalian neuromuscular synapses. In skeletal muscle, dystrophin is also detectable at the non-synaptic membrane of the myofiber, whereas in the electric organ, dystrophin is strictly localized to the postsynaptic membrane, and is not detectable in non-synaptic membranes. Multiple isoforms of dystrophin are present in skeletal muscle, and different isoforms could potentially be targetted to synaptic and non-synaptic membranes. We sought to determine whether the electric organ contains a single, or multiple isoforms of dystrophin, and we show here that the electric organ contains both a and b isoforms of dystrophin. Because dystrophin is found only at the postsynaptic membrane of the electric organ, we conclude that the two isoforms coexist in the postsynaptic membrane.