Analysis of meiotic segregation patterns and interchromosomal effects in sperm from six males with Robertsonian translocations

Purpose To provide more genetic information about meiotic segregation behavior and the possibility of interchromosomal effects (ICE) in spermatozoa from carriers of Robertsonian (Rob) translocations. Materials and methods Meiotic segregation behavior in spermatozoa from six carriers of Rob translocations, four t(13;14), one t(14;22) and one t(13;21), was investigated by dual fluorescence in-situ hybridization (FISH). Aneuploidy for chromosomes 18, X and Y was studied by triple FISH. Results The rate of normal/balanced spermatozoa resulting from alternate segregation ranged from 78.14 to 86.88%. The frequency of unbalanced spermatozoa resulting from adjacent segregation varied between 11.70 and 19.53%. The higher frequencies of aneuploidy for sex chromosome were observed in three Rob translocation carriers. In addition, the increased rates of diploid were found in two t(13;14) carriers. Conclusions Alternate segregation is dominant in the different types of Rob translocations. Some carriers may be at an increased risk for ICE. Electronic Supplementary Material The online version of this article (doi:) contains supplementary material, which is available to authorized users. An increased aneuploidy for sex chromosome observed in three Robertsonian translocation carriers suggests that an interchromosomal effect is likely in some carriers.     

Cumulative exposure to high estradiol levels during the follicular phase of IVF cycles negatively affects implantation

Purpose: To investigate the effect of the cumulative exposure to estradiol (E₂) during the follicular phase on IVF outcome. Methods: Patients were stimulated with recombinant FSH after GnRH agonist suppression and had a day 3-embryo transfer. Estrogen exposure was determined as the area under the curve (AUC) for serum E₂ levels measured from the first day of stimulation through the day after hCG administration. Results: E₂ AUC thresholds for 10th and 90th percentiles were 4704 pg/ml and 16338 pg/ml, respectively. The pregnancy and implantation rates were highest in the 10th–90th percentile group, and were statistically higher in this group than in the >90th percentile group (54.6% vs. 33.3% and 24.8% and 12.9%, respectively, for pregnancy and implantation rates, P < 0.05). Recovered mature oocytes, fertilization, and number and mean score of transferred embryos were similar. Conclusions: High cumulative E₂ exposure during the follicular phase of IVF cycles has detrimental effects on implantation.     

Too old for IVF: are we discriminating against older women?

In vitro fertilization (IVF) in women of advanced age (>42 years) represents only 5%, a comparatively minute part, of the national IVF experience in the United States (US). In view of evolving population dynamics, it, however, also represents proportionally a rather quickly expanding patient need. Because of access restrictions at many IVF programs, this market does not live up to its potential. As best demonstrated by the 2004 US National Summary and Fertility Clinic Report, which for the first time reported pregnancies and births above age 45 year, IVF in women of advanced reproductive age represents a cutting edge area of interest for improving current IVF outcomes. Access to IVF should, therefore, not be withheld based on female age and/or baseline FSH levels. Instead, a definition of acceptable minimal pregnancy and life birth rates could be used to define the limits of offered access to IVF, independent of age and/or baseline FSH levels.     

Sex selective feticide in India

Regarding sex selective abortion in India, all are aware of exclusive female disadvantage. And yet few study reported sizeable selective male feticide as such. This exercise reveals that: (1) the age-old son-preference has slightly declined on the end of the twentieth century, and (2) a substantial selective male feticide are also being committed annually, of course, along with larger selective female feticide.     

Low endometrial volume may predict early pregnancy loss in women undergoing in vitro fertilization

PURPOSE: To evaluate the role of 3-D US measurement of the endometrium during early IVF-pregnancy and before the appearance of gestational sac in the prediction of pregnancies outcome. METHODS: 60 pregnant women following IVF treatment were included in the study. The women underwent transvaginal 3D US measurements of endometrial volume and thickness on day 15-17 post ET. Patients were followed and classified according to pregnancy outcome into 2 further groups. The group with early pregnancy loss and the group with ongoing pregnancy. RESULTS: While no differences were observed between those who miscarried and those who did not in gestational age, endometrial thickness or volume, spontaneous early pregnancy loss was significantly higher in patients with endometrial volume <2 mL as compared to those with endometrial volume >2 mL. CONCLUSIONS: 3-D US measurement of endometrial volume of less than 2 mL during early IVF pregnancy and prior to the appearance of gestational sac is a powerful predictor of pregnancy loss.     

Ways and means of electrical stimulation of respiration

Biomedical Engineering -     

Hydrodynamic bench rigs for testing assisted circulation apparatus and the artificial heart

Biomedical Engineering -     

N-Acetyl-beta-glucosaminidase activity in hydatidiform mole.

The N-acetyl-beta-glucosaminidase activity in hydatidiform mole is two-fold higher than that in full-term placenta. Qualitatively, the enzymes from the two tissues are similar with respect to KM values and pH optima. Both enzymes also contain a new isoenzyme form detectable by polyacrylamide gel electrophoresis. However, the molar enzyme is more susceptible to heat denaturation, presumably due to the presence of a higher level of the heat-labile isoenzyme form A in this tissue. Data are also presented incicating that the placenta is not the source of the N-acetyl-beta-glucosaminidase activity in maternal serum.