False positive rate of an arrayCGH platform for single-cell preimplantation genetic screening and subsequent clinical application on day-3.

In this work, false positive rate of an arrayCGH platform for its use in day-3 single-blastomere analysis was calculated. For this purpose, 38 embryos diagnosed as abnormal on day-3 by FISH were re-biopsied on day-4. Single-cell day-4 arrayCGH diagnosis was then performed. A successful amplification was obtained in 97.4 % (37/38) of the day-4 cells analysed by arrayCGH. Day-3 FISH and day-4 arrayCGH diagnosis were concordant in 35/37 cases. The two discordant embryos were spread and all the cells from each embryo were re-analysed by FISH on day 5. The same error rate (2.7 %) for day-3 FISH and day-4 arrayCGH was obtained when comparing day-5 FISH re-analysis. After this pre-clinical phase, the platform was used for day-3 arrayCGH clinical application in 320 patients (1,760 embryos). Day-3 amplification rate was 98.6 %. An optimal reproductive outcome was obtained when applying arrayCGH to a clinical program: clinical pregnancy rate per cycle of 38.4 % and 60.3 % per transference were obtained, with an implantation rate of 53.5 %. Overall miscarriage rate was 10.6 %. Additionally, day-5 FISH re-analysis was performed in 42 of the embryos from the clinical phase, obtaining a concordance rate of 97.6 % with day-3 arrayCGH.

Redefining advanced maternal age as an indication for preimplantation genetic screening.

In this retrospective study, the utility of preimplantation genetic screening (PGS) in patients with advanced maternal age is evaluated. The patient population consisted of women aged 38-44years and included in a regular IVF programme with or without PGS analysis. Transfer rate, ongoing implantation rate and ongoing pregnancy rate were the main outcome parameters measured. A trend of better ongoing pregnancy rate per oocyte retrieval was observed in patients aged 38 and 39years in the non-PGS group when compared with PGS groups, but better ongoing pregnancy rate per oocyte retrieval was observed in patients 41-44years old in the PGS group. When patients with a low ovarian response accumulated oocytes in several stimulation cycles, clinical outcomes were comparable to those of normal-responder patients. These results show that, although PGS does not benefit patients less than 40years of age, reproductive success increases more than two-fold in patients over 40years, especially in patients with more than six metaphase II oocytes, as a result of a good ovarian response or gamete accumulation, suggesting a redefinition of advanced maternal age as indication for PGS. In this retrospective study, the utility of preimplantation genetic screening (PGS) in patients with advanced maternal age is evaluated. Patient population consisted of women aged 38-44 years and included in a regular IVF programme with or without PGS analysis. Transfer rate, ongoing implantation rate and ongoing pregnancy rate were the main outcome parameters measured. A trend of better ongoing pregnancy rate per ovarian stimulation cycle was observed in patients aged 38-39 years in the non-PGS group when compared with PGS groups, but better ongoing implantation rate was observed in patients aged 41-44 years old in the PGS group. When patients with a low ovarian response (low number of oocytes available for the IVF cycle) accumulated oocytes in several stimulation cycles, their reproductive possibilities were comparable to those of normal-responder patients. These results show that, although PGS does not benefit patients less than 40 years of age, reproductive success increases more than 2-fold in patients over 40 years, especially in patients with more than six metaphase II oocytes, as a result of a good ovarian response or gamete accumulation, suggesting a redefinition of advanced maternal age as indication for PGS.

Vulnerability of peripheral catecholaminergic neurons to MPTP is not regulated by alpha-synuclein.

Although generally considered a prototypical movement disorder, Parkinson's disease is commonly associated with a broad-spectrum of non-motor symptoms, including autonomic dysfunctions caused by significant alterations in catecholaminergic neurons of the peripheral sympathetic nervous system. Here we present evidence that alpha-synuclein is highly expressed by sympathetic ganglion neurons throughout embryonic and postnatal life and that it is found in tyrosine hydroxylase-positive sympathetic fibers innervating the heart of adult mice. However, mice deficient in alpha-synuclein do not exhibit any apparent alterations in sympathetic development. Sympathetic neurons isolated from mouse embryos and early postnatal mice are sensitive to the parkinsonian drug MPTP/MPP(+) and intoxication requires entry of the neurotoxin through the noradrenaline transporter. Furthermore, recovery of noradrenaline from cardiac sympathetic fibers is reduced in adult mice treated with MPTP systemically. However, MPP(+)-induced sympathetic neuron loss in vitro or MPTP-induced cardiac noradrenaline depletion in vivo is not modified in mice lacking alpha-synuclein. This is in clear contrast with the observation that dopaminergic neurons of the central nervous system are significantly less vulnerable to MPTP/MPP(+) in the absence of alpha-synuclein, suggesting different actions of this molecule in central and peripheral catecholaminergic neurons.

Prognostic factors for preimplantation genetic screening in repeated pregnancy loss.

The objective of this study was to identify specific subgroups of recurrent pregnancy loss (RPL) patients of unknown aetiology in whom the selection of chromosomally normal embryos for transfer improves reproductive outcome in preimplantation genetic screening (PGS). A total of 428 PGS cycles were included and chromosomes 13, 15, 16, 18, 21, 22, X and Y were evaluated. In RPL patients < or =37 years, a lower incidence of chromosomal abnormalities (P = 0.0004) and miscarriages (P = 0.0283) was observed, and there were significantly higher pregnancy (P < 0.0384) and implantation (P < 0.0434) rates than in patients >37 years. In the former subset, results showed: (i) significantly higher implantation rates (P = 0.0411) in couples that had experienced a previous aneuploid miscarriage; (ii) similar aneuploidy, pregnancy and implantation rates in couples suffering previous miscarriages during fertility treatments and in those with previous spontaneous pregnancies; (iii) no miscarriages after PGS in couples in whom a fluorescence in-situ hybridization assay showed the male partner's sperm to be abnormal; and (iv) lower implantation rates in couples with > or =5 previous miscarriages, associated with a lower percentage of chromosomally abnormal embryos. It is concluded that PGS is to be strongly recommended when RPL is associated with miscarriages during infertility treatments, chromosomopathy in a previous miscarriage, up to five previous miscarriages and a high incidence of chromosomal abnormalities in spermatozoa.

Impact of chromosomal abnormalities on preimplantation embryo development.

OBJECTIVES: To evaluate the influence of numerical chromosomal abnormalities on preimplantation embryo development. METHODS: This study includes 6936 embryos from 1245 women undergoing preimplantation genetic diagnosis (PGD). Indications for aneuploidy screening were: recurrent miscarriages, implantation failure, severe male factor, advanced maternal age, and mixed causes. Embryo biopsy was performed on day 3, and embryos were co-cultured until day 5, when embryo transfer was performed. RESULTS: In the aneuploidy screening regimen, normal euploid embryos showed significantly higher blastocyst rates (68.2%) compared to chromosomally abnormal (42.8%, p < 0.0001) and mosaic (53.7%, p < 0.0001) embryos. Among aneuploid embryos for autosomes, higher blastocyst rates were observed in trisomies than monosomies, although only statistically significant in patients over 36 years of age (50.8 vs 38.9%; p < 0.0001). In contrast, in embryos with sex chromosomes aneuploidy, similar blastocyst rates were observed between trisomies and monosomy X. CONCLUSION: Embryos with certain types of chromosomal abnormalities were negatively selected during preimplantation embryo development. Despite this selection, a remarkable percentage of chromosomally abnormal embryos can develop normally to blastocyst stage with high probability of implantation and pregnancy.

FISH screening of aneuploidies in preimplantation embryos to improve IVF outcome.

Preimplantation genetic diagnosis (PGD) has transformed the approach to the infertility patient in the IVF setting. Although the principal applications of PGD have been to prevent the transmission of sex-linked diseases, in time and with growing knowledge of the chromosomal abnormalities observed in preimplantation embryos, its applications have widened. Nowadays, apart from its implications in the prevention of transmission of chromosomal and genetic abnormalities, PGD is being used with increased frequency to improve the IVF outcome in patients with advanced maternal age (> or =38 years of age), recurrent miscarriage (> or =2 miscarriages), recurrent IVF failure (> or =3 failed IVF attempts) and severe male infertility. A high incidence of chromosomal abnormalities has been observed in these patient groups.

Actividad del factor tímico sérico en niños recién nacidos desnutridos / Activity of serum thymic factor in undernourished newborn infants

Los pacientes con desnutrición de proteínas y calorías (DPC) tienen una mayor susceptibilidad a algunas infecciones que se han relacionado con atrofia del tejido linfoide y deterioro de la capacidad funcional de los linfocitos. En este estudio se midió la actividad biológica del factor tímico sérico (FTS) de niños recién nacidos desnutridos y sanos, por la capacidad del suero de estos pacientes de inducir la formación de rosetas. E con linfocitos (LFR-E) de bazo de ratones CD-1 timectomizados en presencia de azatioprina. Los resultados sugieren que el suero de niños recién nacidos desnutridos tienen menor actividad de FTS que el suero de los recién nacidos sanos (P<0.005), además son compatibles con una menor población de linfocitos T en desnutridos (14.0 + ou - 3 por ciento) respecto a los sanos (26 + ou - 2 por ciento). La menor actividad de FTS en el suero de los niños recién nacidos desnutridos sugiere que la desnutrición de proteínas y calorías afecta la función endocrina del timo para inducir maduración y diferenciación celular