A mini-atlas of the human blastocyst in vitro.
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Blastocyst↗
Biomedical subjects
A Veiga
Publications and source records attributed to A Veiga.
A retrospective follow-up study on intracytoplasmic sperm injection.
PURPOSE: Genetic aspects of male subfertility and the novelty of intracytoplasmic sperm injection (ICSI) as a new technique can influence the development of zygotes and children born after ICSI. Therefore, we evaluated the outcome of ICSI compared to in vitro fertilization (IVF). METHODS: Data from medical records of 233 total pregnancies and the follow-up of 132 children born after IVF and 120 after ICSI were retrospectively analyzed. RESULTS: No differences were found between ICSI and IVF for early embryonic development and obstetric outcome. In both groups the rate of women undergoing prenatal chromosomal diagnosis was low, 30.0%. The congenital malformation rate was 3.0% after IVF and 1.7% after ICSI, which was not significantly different. Follow-up on development of children born after IVF and ICSI also showed no significant differences. CONCLUSIONS: Our results indicate that at this moment ICSI is a safe procedure. However, a consistent prospective follow-up is still mandatory to exclude possible risks.
Adult↗
Meiotic abnormalities and spermatogenic parameters in severe oligoasthenozoospermia.
The incidence of meiotic abnormalities and their relationship with different spermatogenic parameters was assessed in 103 male patients with presumably idiopathic severe oligoasthenozoospermia (motile sperm concentration < or = 1.5 x 10(6)/ml). Meiosis on testicular biopsies was independently evaluated by two observers. Meiotic patterns included normal meiosis and two meiotic abnormalities, i.e. severe arrest and synaptic anomalies. A normal pattern was found in 64 (62.1%), severe arrest in 21 (20.4%) and synaptic anomalies in 18 (17.5%). The overall rate of meiotic abnormalities was 37.9%. Most (66.7%) meiotic abnormalities occurred in patients with a sperm concentration < or = 1 x 10(6)/ml. In this group, total meiotic abnormalities were found in 57.8% of the patients; of these, 26.7% had synaptic anomalies. When the sperm concentration was < or = 0.5 x 10(6)/ml, synaptic anomalies were detected in 40% of the patients. In patients with increased follicle stimulating hormone (FSH) concentrations, total meiotic abnormalities occurred in 54.8% (synaptic anomalies in 22.6%). There were statistically significant differences among the three meiotic patterns in relation to sperm concentration (P < 0.001) and serum FSH concentration (P < 0.05). In the multivariate analysis, sperm concentration < or = 1 x 10(6)/ml and/or FSH concentration > 10 IU/l were the only predictors of meiotic abnormalities.
Adult↗
Use of co-culture of human embryos on Vero cells to improve clinical implantation rate.
Co-culture of human embryos (n = 384 cycles) to the blastocyst stage using Vero cell monolayers was carried out between August 1995 and December 1997. A total of 2868 zygotes were co-cultured and 1027 embryos reached the blastocyst stage (blastocyst formation rate 35.8%). The blastocysts were frozen in 43.7% of patients. A mean of 1.8 blastocysts was transferred per patient and 95 pregnancies were obtained (pregnancy rate/cycle 24.7%). The blastocyst implantation rate was 23.6%. Miscarriage occurred in 15 patients (15.7%) and ectopic pregnancy in three (3.1%) patients. The multiple pregnancy rate was 32.6%. No differences were observed in the blastocyst rate between poor, normal or high response patients. Blastocyst formation was significantly lower when frozen donor spermatozoa were used. Significantly higher pregnancy rates per transfer and blastocyst implantation rates were attained when embryos were transferred on days 5 or 6 compared with day 7. No advantage was observed when co-culture was used in first cycle IVF patients, in comparison with conventional day 2 replacements. The use of blastocysts for preimplantation genetic diagnosis (PGD) increases the diagnostic reliability and widens diagnostic possibilities. A total of 215 cycles with frozen-thawed co-cultured blastocysts were carried out, with a pregnancy rate of 22.7% per replacement.
Adult↗
[Sequential media: why and how?].
Blastocyst transfer is highly recommended for the following indications to avoid repeated failure of implantation: related to maternal, paternal and cytogenetic aspects on the embryonic side and/or uterus motility. Sequential media have now replaced coculture in order to produce blastocysts. The basic idea of sequential media is to follow embryo's need. There are 2 phases during preimplantation period: the first one corresponds to a development through maternal stores, gathered during maturation, before genomic activation. This requires a complete protection against free radicals (through EDTA), and a decrease in the concentration of glucose and phosphate: mitocondrial function is impaired. Regulation of the endogenous pool is not perfect. Then at the time of genomic activation, there is an increased need for numerous metabolites. Insulin can be added as the I-Receptor appears at the 8-cell stage. The medium used during this phase has to be rich.
Coculture Techniques↗
Confirmation of diagnosis in preimplantation genetic diagnosis (PGD) through blastocyst culture: preliminary experience.
Three cases of preimplantation genetic diagnosis (PGD) (two for sexing and one for aneuploidy screening) are presented. Embryo biopsy was performed at day 3 and diagnosis was established with fluorescent in situ hybridization (FISH). Embryos not used for replacement were cultured in sequential media for blastocyst development. Blastocyst rate was 39.3 per cent. Confirmations of diagnosis were established with FISH in blastocysts and arrested embryos. Mosaicism was observed in 7/8 blastocysts (mean number of cells analysed: 55.5) and 5/8 arrested embryos. The percentage of abnormal cells was 17.1 per cent for blastocysts and 54 per cent for arrested embryos. Polypoid cells were observed in 4/8 blastocysts. Confirmation of diagnosis at the blastocyst stage is a useful tool in PGD.
Aneuploidy↗
Successful use of a laser for human embryo biopsy in preimplantation genetic diagnosis: report of two cases.
PURPOSE: The use of Tyrode's acid to drill the zona pellucida for embryo biopsy is the most widely used methodology in preimplantation genetic diagnosis. Instead of this, we propose the use of a 1.48-micron diode noncontact laser, which is quicker, simpler, and safer. METHODS: The laser beam was tangentially guided to the zona pellucida of the embryo. Depending on zona pellucida measurement, two to four consecutive shots of 8-22 msec were necessary to drill the zona pellucida of the 13 embryos biopsied for two patients (hemophilia carriers). RESULTS: Female embryos were replaced into the uterus of the patients (1.5 embryos/replacement). One single pregnancy was established (33.3% implantation rate). Coculture of untransferable embryos showed a blastocyst rate of 66.7% (4/6) for male embryos and 25% (1/4) for abnormal ones. CONCLUSIONS: These results demonstrate the safety and usefulness of laser methodology in preimplantation genetic diagnosis.
Adult↗
Psychiatric morbidity in couples attending a fertility service.
The structured clinical interview for diagnosis (axis 1) according to the Diagnostic and Statistical Manual for Mental Disorders (DSM-III-R) was used to assess psychiatric morbidity in 110 infertile patients. They were divided into two groups according to whether referral to the service of psychosomatic medicine was deemed advisable by the physician in charge. Psychiatric disorders were diagnosed in 39 of 56 (69.6%) patients in the referred group and in 13 of 54 (24.1%) in the non-referred group. Psychiatric morbidity was found in 61.1% of females and 21% of males. Adjustment disorders were found in 59.6% (31/52) of all patients, in 59% (24/39) of patients among the referred group and in 61.5% (8/13) of patients among the non-referred group. Fourteen (67%) of 21 women in the referred group with adjustment disorders suffered from anxiety. In addition, 33.3% of patients in the non-referred group showed important psychological dysfunction, although DSM-III-R criteria were not met. Psychiatric morbidity was significantly associated with the number of treatment cycles and female gender in the whole study population, as well as with the type and length of infertility in the non-referred group. Psychological services in an infertility clinic help to identify at an early stage those individuals who are more likely to be vulnerable. This would enable psychological interventions to be targeted towards those in greater need.
Female↗
Randomized comparison of three media used for embryo culture after intracytoplasmic sperm injection.
Since the metabolic requirements of fertilization and early embryonic development are very different, we have tested a new culture medium (EllioStep2, Ellios Bio-Media, Paris, France) specially designed for the first cleavages and compared it with two conventional media: BM1 (Ellios Bio-Media, Paris, France) and IVF50 (Scandinavian IVF Science, Gothenburg, Sweden). In order to avoid any interference with fertilization, the test was performed as part of an intracytoplasmic sperm injection (ICSI) study. A total of 416 ICSI attempts were randomly performed using one or other of the media. After sperm injection, oocytes were incubated either in EllioStep2 or in BM1 or in IVF50. The embryo quality, pregnancy and implantation rates, number of frozen embryos were compared in the different media. The percentage of fair embryos (grades 4 and 3) was significantly higher when EllioStep2 was used than when oocytes was cultured in BM1 medium (54 versus 47%; P < 0.01) or in IVF50 (69 versus 61%; P < 0.01). The pregnancy rate per transfer and the implantation rate were not significantly higher with EllioStep2 than with BM1 or IVF50. However, the percentage of embryo freezings per attempt was significantly higher with EllioStep2 than with BM1 (47/105 versus 28/105; P < 0.01). In conclusion, the use of EllioStep2 is associated with an increase in embryo quality permitting a higher number of embryo freezings.
Adult↗
Improved methods for blastocyst formation and culture.
Transfer at the blastocyst stage has been proposed to increase the pregnancy rates after in-vitro fertilization (IVF) and embryo transfer. In the first period of experiments, culture in a single medium, from fertilization to blastocyst led to disappointing results: low blastocyst formation rates and low implantation rates per blastocyst transferred. Then the period of co-culture began (starting with animals in the early 1980s and with humans in the early 1990s). With this technique, using tubal or granulosa cells or layers obtained from established cell lines of transport epithelium origin, blastocyst formation has reached approximately 50% and the overall implantation rate is approximately 25%. The embryos obtained have high numbers of cells (> 200 cells for a day 6 expanded blastocyst). Co-culture with fibroblasts has been found to be useless. This technology has been proven reliable and reproducible: Blastocyst formation is highly dependent on maternal and paternal factors. It has enabled the design of efficient freezing and thawing protocols. Numerous interesting observations have been obtained to reach the third period, i.e. the use of sequential media. A simple medium is used for fertilization, then another one is used from fertilization up to the 4-cell stage (beginning of waves of transcription), then a third medium is used for development up to the blastocyst stage. The results obtained seem very similar to the one obtained with co-culture. Obviously it is now time, in humans, to switch to sequential media.
Animals↗
Chromosome analysis of human preimplantation embryos.
Although karyotyping is the ideal method for diagnosing chromosome anomalies in the human embryo, the detection of chromosome anomalies in preimplantation human embryos by classical cytogenetics is extremely difficult. Nowadays, fluorescent in situ hybridization (FISH) in interphase nuclei is the method of choice. Both karyotype studies and FISH analysis of human preimplantation embryos obtained after in vitro fertilization (IVF) treatment revealed a high rate (25-51%) of chromosomally abnormal embryos. FISH analysis showed that chromosome mosaicism (22-24%) and chaotic embryos (7-26%) were the most frequent chromosome anomalies. Therefore, it seems that natural selection may be the reason for the low implantation rates of human preimplantation embryos in IVF programs. Although it is not possible to carry out such studies on embryos from natural conceptions, frequent occurrence of chromosome mosaicism and chaotically dividing embryos may apply to in vivo conception and explain the low fecundity rates in humans.
Blastocyst↗
Treatment of polycystic ovary patients undergoing IVF.
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Abortion, Spontaneous↗
Current status of preimplantation diagnosis.
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Chromosome Aberrations↗
Laser blastocyst biopsy for preimplantation diagnosis in the human.
A new methodology for blastocyst biopsy that uses a 1.48 microm diode laser is described. Trophectoderm cells are biopsied after laster zona drilling and culture, fixed and processed for fluorescent in situ hybridisation (FISH) analysis. Preliminary results on the efficiency of the procedure and blastocyst recovery rate are promising. Blastocyst laser biopsy is a useful tool in preimplantation genetic diagnosis (PGD) as it allows a more reliable diagnosis and widens the diagnostic possibilities on account of the higher number of cells obtained in the biopsy.
Biopsy↗
Ureteral lesion secondary to vaginal ultrasound follicular puncture for oocyte recovery in in-vitro fertilization.
Techniques of oocyte retrieval have progressed from laparoscopy to transvaginal follicular aspiration under ultrasonographic control. This highly efficient method, routinely used nowadays, is not free of complications. We present a case of a ureteral lesion secondary to vaginal ultrasound follicular puncture for oocyte recovery in in-vitro fertilization. Despite the surgical procedure to reimplant the ureter, the patient achieved a twin pregnancy which is ongoing uneventfully.
Adult↗
Tributyltin oxide affects energy production in the yeast Rhodotorula ferulica, a utilizer of phenolic compounds.
Rhodotorula ferulica, a yeast able to utilize phenolic compounds, was chosen for evaluating the effects of tributyltin oxide (TBTO) on this utilization. TBTO reduced respiratory capacity when vanillic or benzoic acid was the energy source. The ATP level of the cells was severely affected by 2 microM TBTO. The mitochondrial ATPase was strongly inhibited by 0.5 microM TBTO, whereas the activity of the plasma membrane ATPase was not affected by concentrations of TBTO up to 30 microM. Our data support the hypothesis that the target for TBTO action is the mitochondrial ATPase, resulting in a severe disturbance of the yeast utilization of aromatic compounds.
Adenosine Triphosphatases↗
[Idiopathic ventricular fibrillation: apropos of 2 clinical cases].
We describe two patients with idiopathic ventricular fibrillation recently evaluated to whom it was implanted a cardioversor desfibrillator system. It is our purpose to make a brief review of the etiology, diagnostic procedures, therapy and prognosis of this clinical entity, which is an important rare cause of sudden cardiac death.
Adult↗
Optimization of implantation in the in-vitro fertilization laboratory.
Implantation failure rates after in-vitro fertilization (IVF) can be reduced in the IVF laboratory using two different techniques: assisted hatching and embryo co-culture on monolayer feeder cells. A review of the different methodologies and the results gained using these techniques is reported. Preliminary results obtained in the Reproductive Medicine Service of the Institut Universitari Dexeus, Barcelona, Spain using these techniques are also presented.
Coculture Techniques↗