Vitrification does not affect birth weight: lessons from the oocyte donation model.

RESEARCH QUESTION: Is embryo cryopreservation a cause of high birth weight and large for gestational age (LGA) in singletons resulting from vitrified-warmed embryo transfer? DESIGN: Retrospective cohort study evaluating 670 oocyte recipients who underwent fresh (367 cycles) or vitrified-warmed embryo transfer (303 cycles) at Instituto Bernabeu between July 2017 and March 2019. All single blastocyst transfers carried out in an artificial cycle that resulted in a singleton live birth were included. RESULTS: Maternal age (42.21 ± 4.45; 42.79 ± 3.83; P = 0.519), body mass index (23.34 ± 3.69; 23.80 ± 3.78; P = 0.075), gestational age (38.96 ± 1.97; 38.77 ± 2.15; P = 0.207), maternal smoking (10.8%; 13.0%; P = 0.475), gestational diabetes (4.9%; 4.3% P = 0.854), preeclampsia (2.7%; 5.6%; P = 0.074), hypertensive disorders (3.3%; 2.3%; P = 0.494), maternal parity (multiparous 18.5%; 14.5%; P = 0.177) and liveborn gender (female 44.5%; 48.8%; P = 0.276) were not significantly different between fresh or vitrified-warmed groups. Endometrial thickness was significantly higher in the fresh versus vitrified-warmed group (8.83 ± 1.73 versus 8.57 ± 1.59; P = 0.035, respectively). Oocyte donor height was similar between the fresh versus vitrified-warmed group (163.22 ± 5.88 versus 164.27 ± 6.66 cm; P = 0.057, respectively). Mean birth weight was not significantly different (3239.21 ± 550.43; 3224.56 ± 570.83; adjusted P = 0.058). No differences were observed in macrosomia (7.1%; 6.3%; adjusted OR 0.857, 95% CI 0.314 to 2.340, P = 0.764), LGA (6.0%; 6.7%; adjusted OR 0.450, 95% CI 0.176 to 1.149, P = 0.095), pre-term birth (10.9%; 9.0% adjusted P = 0.997), very pre-term birth (0.8%; 1.3%; adjusted P = 1.000), extremely pre-term birth (0%; 1.0%; adjusted P = 0.998); underweight (10.0%; 7.0%; adjusted P = 0.050); very low weight (0.6; 1.1%; adjusted P = 1.000) and small for gestational age (1.9%; 0.7%; adjusted P = 0.974) between fresh or vitrified-warmed groups. CONCLUSION: This study eliminates potential confounders that might influence fetal growth and demonstrates that embryo vitrification and warming procedures do not affect birth weight.

On-campus food environment, purchase behaviours, preferences and opinions in a Norwegian university community.

OBJECTIVE: To assess the food environment at OsloMet, through the nutritional profile and processing level of available commercial foods and drinks, as well as to determine food-purchasing behaviours, preferences and opinions on the food environment, in order to identify whether interventions on campus need to be conducted. DESIGN: Cross-sectional descriptive study. SETTING: Pilestredet and Kjeller campus of OsloMet (Norway). PARTICIPANTS: To analyse the nutritional profile of products offered at all food outlets (seven canteens, three coffee shops and two vending machines) at the main campuses three criteria were applied: those proposed by the Spanish Agency for Food Safety and Nutrition, the UK nutrient profiling model and those of the Food and Drink Industry Professional Practices Committee Norway. In addition, products were classified by processing level, using the NOVA system. Food purchasing, food choice behaviours and opinions were analysed through a survey online, in which 129 subjects participated. RESULTS: With regard to the first of the objectives, the combination of the above-mentioned criteria showed that 39·8 % of the products were 'unhealthy' and 85·9 % were 'ultra-processed'. Regarding the second objective, the most important determinants of food choice were taste, convenience, and cost and nutrition/health value. The most common improvements suggested were lowering the cost, improving the allergen information on labelling and increasing the variety of fresh and healthy foods. CONCLUSIONS: A high proportion of the products offered were considered 'unhealthy' and highly processed. Interventions that improve food prices, availability and information on labelling would be well-received in this community.

Protein acetylation affects acetate metabolism, motility and acid stress response in Escherichia coli.

Although protein acetylation is widely observed, it has been associated with few specific regulatory functions making it poorly understood. To interrogate its functionality, we analyzed the acetylome in Escherichia coli knockout mutants of cobB, the only known sirtuin-like deacetylase, and patZ, the best-known protein acetyltransferase. For four growth conditions, more than 2,000 unique acetylated peptides, belonging to 809 proteins, were identified and differentially quantified. Nearly 65% of these proteins are related to metabolism. The global activity of CobB contributes to the deacetylation of a large number of substrates and has a major impact on physiology. Apart from the regulation of acetyl-CoA synthetase, we found that CobB-controlled acetylation of isocitrate lyase contributes to the fine-tuning of the glyoxylate shunt. Acetylation of the transcription factor RcsB prevents DNA binding, activating flagella biosynthesis and motility, and increases acid stress susceptibility. Surprisingly, deletion of patZ increased acetylation in acetate cultures, which suggests that it regulates the levels of acetylating agents. The results presented offer new insights into functional roles of protein acetylation in metabolic fitness and global cell regulation.

Impact of Group vs Individual Embryo Culture Strategies on Blastocyst and Clinical Outcomes.

Embryo culture is one of the most important steps in an assisted reproduction laboratory. Embryos can be cultured individually, one embryo per media drop, or in groups, culturing several embryos in the same media drop. Due to the controversy generated on this subject, we wondered which embryo culture method would have the best results in terms of quality and blastocyst formation rate. We designed a prospective randomized study comparing two different embryo culture strategies: group and individual embryo culture. The data were obtained from 830 embryos from 103 egg donation treatments. The zygotes were randomized into two groups: individual culture (group 1) or group culture (group 2). The embryos were cultured in 35-µl drops until day 5 when they were classified morphologically. We observed a significant increase in the blastocyst formation rate and in the usable embryo rate in individual culture on day 5 compared to group culture. However, good embryo quality (A/B blastocysts), implantation, and pregnancy rates were similar regardless of the type of embryo-culture. As a conclusion, individual culture may increase blastocyst formation rate and may benefit embryo quality on day 5. Our results support previous reports suggesting that individual culture could improve embryo development.