[Reflections on the beginning of a new human individual]. / Reflexiones sobre los inicios del individuo humano.

Although there is very little doubt that when a child is born a new actual person can be identified, there is continuous debate as to the moment in embryological development when that same person begins its existence. Based on today's knowledge of human fertilization and the early stages of embryo development, this position paper examines three theses that deal with the establishment of personhood. The first thesis stipulates that a human individual exists prior to syngamy. Although the sperm has penetrated the plasmatic membrane of the oocyte, the genetic information contained in both gametes remain separated in the male and female pronucleus; thus, the oocyte contains the sum of two identities responsible for creating a new individual. This paper will argue that a human individual has not yet formed. The second thesis recognizes that with syngamy, a unicellular structure (zygote) is established, endowed with genetic individuality and with the potential to become a person maintaining that same genetic framework throughout its lifetime. The third thesis argues that although genetic individuality is established with syngamy, the ontological individuality is only reached once genetic expression and cellular specialization are achieved and twinning is no longer possible (15 days after fertilization).

Convergence Properties of Certain Minres Algorithms.

Levin (1988) has challenged the convergence properties of the Harman and Jones (1966) method of Minres factor analysis. Levin claimed that convergence of the Harman and Jones method is not guaranteed and that a modified version of this method, with proven convergence, is to be preferred. In the present article it is shown that both claims are invalid. Monotone convergence of the Harman and Jones method is guaranteed whereas the modified version, proposed by Levin, may converge to an incorrect solution. Levin has also claimed that the rank-one version of the Harman and Jones method, as implemented in a method by Zegers and ten Berge (1983) lacks a valid convergence proof, and that a method suggested by Comrey and Ahumada (1964, 1965) should be used instead. It is shown that these claims, too, should be reversed.

A Fast and Simple computational Method of Minimum Residual Factor Analysis.

Some new procedures for minimum residual factor analysis are presented. First a successive method developed by Comrey is modified in order to guarantee convergence and to provide a way to handle Heywood cases. Next, this modified Comrey procedure is extended to a simultaneous procedure which is computationally simpler and faster than the Minres method developed by Harman and Jones. This latter method, however, satisfies a stronger necessary condition for the minimum of the sum of squared off-diagonal residuals. Some empirical results are presented. These are in accordance with the theoretical considerations; that is, the Harman and Jones procedure tends to be slower, but attains in general a lower value for the sum of squared off-diagonal residuals.

The cervical factor in patients with ovulatory infertility.

Thirty patients with ovulatory infertility had two consecutive postcoital tests. Couples with inconclusive or abnormal results had in vitro sperm penetration tests, using donor mucus and donor sperm. The quality of the cervical mucus, the concentration of plasma oestradiol and luteinising hormone and the result of the post-coital test were assessed each day. After two consecutive cycles, the postcoital test was normal in 84 per cent, inconclusive in 12 per cent and abnormal in 4 per cent of the women. The in vitro cross reaction test showed that two couples had definite abnormality in the sperm-cervical mucus interaction and one couple were having inadequate coitus. Normal post coital tests should not be expected with an Insler cervical mucus score of less than 8. Normal postcoital tests were found between days -2 and +1 with respect to the luteinising hormone peak. There is a direct relation between the plasma oestradiol concentration and the individual cervical score but the predictability of plasma oestradiol values for a given cervical score is very poor. The plasma oestradiol concentration was significantly different between groups having cervical scores less than 7 and 8-10 or 11-12 (p less than 0.01).

Efecto de la concentracion diaria de estradiol en las caracteristicas morfologicas del complejo cumulo-corona-ovocito obtenido en programas de fecundacion in vitro. / Effect of the daily concentration of estradiol on the morphological characteristics of the cumulus-corona-oocyte complex obtained in fertilization in vitro programs

El presente estudio analiza la relacion existente entre la concentracion diaria de estradiol en plasma y la morfologia del complejo cumulo-corona-ovocitos (CCO), obtenidos de aspiracion folicular en un programa de fecundacion in vitro (FIV). De un total de 99 ovocitos pertenecientes a 27 mujeres incorporadas en este estudio, 66% fueron morfologicamente del tipo II; 12% del tipo III, y 16% del tipo IV. El 80,6% de los ovocitos que se fertilizaron corespondian al tipo II, y 89,6% de los ovocitos que se segmentaron eran de esta misma caracterizacion morfologica. La concentracion diaria de estradiol en los dias que preceden a la aspiracion folicular supera al 100% cuando se obtienen ovocitos del tipo II. Sin embargo, en aquellos casos en que se obtienen ovocitos tipo III o IV el estradiol experimenta una estabilizacion en las 48 horas que preceden a la aspiracion folicular, y el incremento acumulativo total no sepera el 80%. Por otra parte, el aumento del volumen folicular total presenta un paralelismo con el incremento diario de estradiol. Cuando este paralelismo se quiebra, la probabilidad de encontrar ovocitos no fertilizables aumenta significativamente

Estudio diagnostico de 114 parejas infertiles. / Diagnostic study of 114 infertile couples

En 114 parejas estudiadas por infertilidad el porcentaje de los factores responsables fue el siguiente: tubario-peritoneal 44, endocrinogonadal 32, masculino 24, uterino corporal 2, uterino cervical 1 y no precisado 13. En 16 parejas existio asociacion de 2 factores. Los siguientes procedimientos demostraron ser imprescindibles en el diagnostico de la infertilidad: histerosalpingografia, laparoscopia, biopsia de endometria, analisis de semen, evaluacion del moco cervical, determinacion de FSH y prolactina por radioinmunoanalisis, y politomografia de silla turca