Impact of oxygen tension according to embryo stage of development: a prospective randomized study.

Human embryo culture under 2-8% O2 is recommended by ESHRE revised guidelines for good practices in IVF labs. Nevertheless, notably due to the higher costs of embryo culture under hypoxia, some laboratories perform embryo culture under atmospheric O2 tension (around 20%). Furthermore, recent meta-analyses concluded with low evidence to a superiority of hypoxia on IVF/ICSI outcomes. Interestingly, a study on mice embryos suggested that oxidative stress (OS) might only have an adverse impact on embryos at cleavage stage. Hence, we aimed to demonstrate for the first time in human embryos that OS has a negative impact only at cleavage stage and that sequential culture conditions (5% O2 from Day 0 to Day 2/3, then «conventional¼ conditions at 20% O2 until blastocyst stage) might be a valuable option for human embryo culture. 773 IVF/ICSI cycles were included in this randomized clinical trial from January 2016 to April 2018. At Day 0 (D0), patients were randomized using a 1:2 allocation ratio between group A (20% O2; n = 265) and group B (5% O2; n = 508). Extended culture (EC) was performed when ≥ 5 Day 2-good-quality-embryos were available (n = 88 in group A (20% O2)). In subgroup B, 195 EC cycles were randomized again at Day 2 (using 1:1 ratio) into groups B' (5% O2 until Day 6 (n = 101)) or C (switch to 20% O2 from Day 2 to Day 6 (n = 94). Fertilization rate, cleavage-stage quality Day 2-top-quality-embryo (D2-TQE), blastocyst quality (Day 5-top-quality-blastocyst (D5-TQB) and implantation rate (IR) were compared between groups A and B (= cleavage-stage analysis), or A(20% O2), B'(5% O2) and C(5%-to-20% O2). Overall, characteristics were similar between groups A and B. Significantly higher rates of early-cleaved embryos, top-quality and good-quality embryos on Day 2 were obtained in group B compared to group A (P < 0.05). This association between oxygen tension and embryo quality at D2 was confirmed using an adjusted model (P < 0.05). Regarding blastocyst quality, culture under 20% O2 from Day 0 to Day 6 (group A) resulted in significantly lower Day 5-TQB number and rates (P < 0.05) compared to both groups B' and C. Furthermore, blastocyst quality was statistically equivalent between groups B' and C (P = 0.45). At Day 6, TQB numbers and rates were also significantly higher in groups B' and C compared to group A (P < 0.05). These results were confirmed analyzing adjusted mean differences for number of Day 5 and Day 6 top quality embryos obtained in group A when compared to those respectively in groups B' and C (P < 0.05). No difference in clinical outcomes following blastocyst transfers was observed. These results would encourage to systematically culture embryos under hypoxia at least during early development stages, since OS might be detrimental exclusively before embryonic genome activation.

Synthesis of silver nanoparticles dispersed in various aqueous media using laser ablation.

The particle size, morphology, and stability of Ag-NPs were investigated in the present study. A Q-Switched Nd: YAG pulsed laser (λ = 532 nm, 360 mJ/pulse) was used for ablation of a pure Ag plate for 30 min to prepare Ag-NPs in the organic compound such as ethylene glycol (EG) and biopolymer such as chitosan. The media (EG, chitosan) permitted the making of NPs with well dispersed and average size of Ag-NPs in EG is about 22 nm and in chitosan is about 10 nm in spherical form. Particle size, morphology, and stability of NPs were compared with distilled water as a reference. The stability of the samples was studied by measuring UV-visible absorption spectra of samples after one month. The result indicated that the formation efficiency of NPs in chitosan was higher than other media and NPs in chitosan solution were more stable than other media during one month storage. This method for synthesis of silver NPs could be as a green method due to its environmentally friendly nature.

Cytogenetic study in cases with recurrent abortion in Saudi Arabia.

BACKGROUND: A proportion of cases with repeated abortion are caused by chromosomal abnormality in one of the parents. Several studies have been done to determine the role of chromosomal abnormalities in couples with repeated fetal loss in various countries. None of these studies was done in the Arab Peninsula. MATERIAL AND METHODS: Cytogenetic study was done for 193 consecutive Saudi couples who presented with repeated abortion at the King Khalid University Hospital in Riyadh, Saudi Arabia. RESULTS: We found that the frequency of chromosomal abnormalities was not significantly different from that reported worldwide. The nature of those abnormalities and their relation to the obstetric history of cases were discussed. CONCLUSION: This study should help physicians working in the region to realize the contribution of chromosomal abnormalities to cases of repeated fetal loss. It should also help in setting priorities of cytogenetic screening in individual cases.

Outcome of pregnancies in epileptic women: a study in Saudi Arabia.

We studied the outcome of 79 pregnancies in 44 Saudi women who had epilepsy. Their mean age was 28+/-6.5 years and the number of pregnancies studied varied from one to six. Nineteen subjects had generalized seizures, 16 had partial seizures and nine were unclassified. The commonest drug prescribed was carbamazepine and the majority of the women (61%) were on monotherapy. The seizures were controlled in 53 pregnancies (67%). Spontaneous vertex deliveries were the commonest. The indications for intervention by lower segment Caesarean section, forceps or ventouse were foetal distress, pre-eclamptic toxaemia (PET), eclampsia, breech presentation and prolonged labour. The most frequent adverse outcome in the babies was low birth weight (<2.5 kg) in nine pregnancies. The frequency of congenital malformation was 2.5%. Low birth weight was associated with prematurity, PET, congenital malformation and polytherapy. Avoidance of polytherapy appears to be the most feasible intervention in reducing the frequency of low birth-weight children by epileptic mothers.

Sickle cell and G-6-PD deficiency gene in cord blood samples: experience at King Khalid University Hospital, Riyadh.

Cord blood samples (1039) collected at King Khalid University Hospital were analysed for abnormal haemoglobins using electrophoresis at alkaline and acid pH, for glucose-6-phosphate dehydrogenase (G-6-PD) deficiency using spectrophotometric method and for G-6-PD phenotypes using electrophoresis and specific staining. Only two samples showed the presence of Hb AS and no case of sickle cell anaemia was identified. The Hb S gene frequency was 0.00096. This was the lowest frequency identified so far in different regions of Saudi Arabia. The frequency of G-6-PD deficiency was calculated separately in the males and females, and was found to be 3.605 per cent in the males and 0.195 per cent in the females. Phenotyping showed the presence of G-6-PD-B+ as the normal enzyme at a frequency of 0.943 in both males and females and G-6-PD-A+ at a frequency of 0.0208 in males and 0.0059 in females. The deficient variant was mainly G-6-PD Mediterranean which occurred at a frequency of 0.0341 and 0.0019 in males and females, respectively. Only one case of G-6-PD-A- was identified in the males giving a frequency of 0.0019. This is the first report of Hb S and G-6-PD deficiency genes in cord blood samples in Riyadh. Comparison of the results in Riyadh with values reported elsewhere showed that Riyadh had the lowest frequency of both Hb S and G-6-PD deficiency gene.

Basement membrane thickening in the placentae from diabetic women.

A light microscopy study was carried out on 48 placentae. Seventeen placentae were obtained from non-diabetic mothers while the other 31 placentae were from both women with controlled diabetes and women who had an abnormality of the glucose tolerance test. All the women delivered at 38-40 weeks of gestation. Placentae from diabetic patients showed immaturity of the villi, hypertrophy of the capillaries and thickening of the basement membrane of the trophoblastic villi (3.2 +/- 0.35 microns) and the amniotic membrane (1.8 +/- 0.3 microns). Focal fibrinoid necrosis, an increase in the number of Hofbauer cells and dilatation of villi capillaries were also commonly observed in placentae from diabetic mothers, and the normal cuboidal cells lining the amniotic membrane tended to become tall columnar (17.6 +/- 6.3 microns) with distally located nuclei. Similar findings were observed in patients who had a potentially abnormal glucose tolerance test, which suggests the possibility of primary lesion in origin. Therefore, control of hyperglycemia may only partially prevent the development of placental abnormalities.

Photosensitivity of respiration in Neurospora mitochondria. A protective role for carotenoid.

1. The effect of visible light on respiratory activity was studied in two strains of Neurospora crassa, one a wild-type strain able to synthesize carotenoid and the other an albino mutant lacking carotenogenic activity. Light had no effect on growth under the conditions studied, but inhibited respiration of hyphal suspensions. the degree of inhibition being dependent on the carotenoid content of the hyphae. 2. In studies of respiration of isolated mitochondria, three types of photosensitive site were detected. These were the flavo-protein dehydrogenases themselves, a site separate from the latter also associated with the dehydrogenase but re-activatable by treatment with a thiol reagent, and the respiratory quinone, ubiquinone. Cytochrome oxidase, previously reported as photosensitive from many sources, was not appreciably affected by light in these preparations. 3. The degree of inactivation of the respiratory quinone was dependent on the amount of carotenoid in the preparation, high concentrations of the pigment in the mitochondrial membranes providing substantial protection against the effect of light. 4. Separation of the inner and outer membranes of mitochondria showed that under conditions where carotenoid appears to protect quinone, significant amounts are found in the inner mitochondrial membrane, oterhwise carotenoid is restricted to the outer membrane.