102 A delay in maternal zygotic transition may lead to early embryonic loss in poor-quality bovine blastocysts

Increased genetic potential and performance of dairy cows has coincided with a decline in fertility. Early embryonic mortality accounts for 75-80% of this decline in fertility, costing the industry over $1.28 trillion worldwide. Despite advancements in assisted reproductive technologies and embryo transfer, many transferred embryos do not survive past Day 24 of gestation, suggesting flaws in embryo selection for transfer. It was hypothesised that visually lower-quality IVF Day 7 blastocysts were developmentally delayed as a result of altered mitotic signalling and were at higher risk of embryo mortality. To identify potential causes for early embryo mortality in IVF embryos, RNA-Seq was performed on 6 categories of Day 7 blastocysts: stages (S) 5 (early), 6 (full), and 7 (expanded), with quality scores (Q) of 1 or 2. Oocytes were matured, fertilized by routine procedure, and cultured for 7 days. Blastocysts were classified and graded, separated into the six categories, and subjected to Pronase digestion of the zona pellucida. From three biological replicates of each blastocyst group, RNA was extracted and submitted for RNA-sequencing. Secondary bioinformatics and analyses were performed using R to determine differentially expressed genes. When S7.Q1 blastocysts were compared to other categories, 55 genes were consistently differentially expressed (P<0.05) in S5.Q1 or 2 and S6.Q2. Of these 55 genes, 15 were significantly upregulated (>1.5 fold change), and 40 were downregulated (<−1.5 fold change). The nine most common upregulated genes in S5.Q1 or 2 and S6.Q2, compared with S7.Q1, were BTG4, ARGFX, GPC4, BOC, CNTNAP2, NR3C2, CCDC7, and PHYHIPL. The five most common downregulated genes included MUC1, HSD3B1, ADAM19, EVPL, and TGM1. The EVPL and TGM1 proteins are associated with cell barrier permeability, and a lack of TGM1 has been shown to cause neonatal death in mice. Therefore, early embryo mortality may begin with decreased EVPL and TGM1, limiting cell permeability and communication between blastomeres. This limited communication might delay gene expression in the embryo at the 4- to 8-cell stage, delaying the maternal zygotic transition (MZT), in spite of continued cell division. This explanation is supported by the observed increase in ARGFX and BTG4 mRNA. Normally, stored maternal BTG4 mRNA becomes translated during the MZT and degrades maternal mRNA. The increase of BTG4 mRNA in poor-quality embryos may reflect delayed translation of BTG4 and delayed MZT. The mRNA transcripts increased in poor-quality blastocysts may be excess maternal mRNA not yet degraded, like BTG4. The decreased mRNA transcripts observed may be indicative of zygotic genes which have not yet been transcribed. For instance, MUC1 is necessary for proper embryo implantation, and HSD3B1 converts placental pregnenolone to progesterone and produces a precursor to oestradiol. The delayed transcription of both MUC1 and HSD3B1 may impair maternal recognition of pregnancy, implantation, and communication to the maternal endometrium via oestradiol, thereby causing embryo mortality. This research was supported by USDA NNF 2016-38420-25289 and Zoetis Inc.

Normal radiological lymph node appearance in the thorax

Modern treatment of esophageal cancer is multimodal and highly dependent on a detailed diagnostic assessment of clinical stage, which includes nodal stage. Clinical appraisal of nodal stage is highly dependent on knowledge of normal radiological appearance, information of which is scarce. We aimed to describe lymph node appearance on computed tomography (CT) investigations in a randomly selected cohort of healthy subjects. In a sample of the Swedish Cardiopulmonary bioimage study, which investigates a sample of the Swedish population aged 50-64 years, the CT scans of 426 subjects were studied in detail concerning intrathoracic node stations relevant in clinical staging of esophageal cancer. With stratification for sex, the short axis of visible lymph nodes was measured and the distribution of lymph node sizes was calculated as well as proportion of patients with visible nodes above 5 and 10 millimeters for each station. Probability of having any lymph node station above 5 and 10 millimeters was calculated with a logistic regression model adjusted for age and sex. In the 214 men (aged: 57.3 ± 4.1 years) and 212 women (aged: 57.8 ± 4.4 years) included in this study, a total of 309 (72.5%) had a lymph node with a short axis of 5 mm or above was seen in at least one of the node stations investigated. When using 10 mm as a cutoff, nodes were visible in 29 (6.81%) of the subjects. Men had higher odds of having any lymph node with short axis 5 mm or above (OR 3.03 95% CI 1.89-4.85, P < 0.001) as well as 10 mm or above (OR 2.31 95% CI 1.02-5.23, P = 0.044) compared to women. Higher age was not associated with propensity for lymph nodes above 5 or 10 millimeters in this sample. We conclude that, in a randomly selected cohort of patients between 50 and 64 years, almost 10% of the men and 4% of the women had lymph nodes above 10 millimeters, most frequently in the subcarinal station (station 107). More than half of the patients had nodes above 5 millimeters on CT and men were much more prone to have this finding. The probability of finding lymph nodes in specific stations relevant of esophageal cancer is now described.

P6271The effect of semaglutide once weekly on MACE and blood pressure by race and ethnicity: SUSTAIN 6 post hoc analysis

Background

In SUSTAIN 6, subcutaneous semaglutide once weekly added to standard of care significantly reduced major adverse cardiovascular events (MACE: non-fatal myocardial infarction, non-fatal stroke or death) vs placebo over 2 years in T2D subjects.

Purpose

Assess the effect of semaglutide vs placebo on MACE and blood pressure (BP) by race and ethnicity in a post hoc analysis of SUSTAIN 6.

Methods

Subjects were randomised to semaglutide 0.5 mg, 1.0 mg or volume-matched placebo. Data for the two semaglutide-dose groups were pooled and compared to the pooled placebo groups. Time-to-event data were analysed with a Cox proportional hazards model. Changes from baseline to week 104 were analysed using analysis of covariance. The interaction between treatment and subgroup was added to the models.

Results

Overall, 3,297 patients received treatment. Subgroups included Caucasian, Asian, Black/African American, Other (race), and Hispanic, non-Hispanic (ethnicity). Mean baseline characteristics were similar across subgroups (age 64.7 years, HbA1c 8.7%, diabetes duration 14.2 years). Time to composite MACE and individual components were improved with semaglutide across all subgroups. Semaglutide affected BP similarly across race and ethnicity, except for systolic BP in Black/African American subjects (Table).

Race Ethnicity Caucasian Asian Black/African American Other Interaction p-value Hispanic Non-Hispanic Interaction p-value Semaglutide (n) 1,384 121 108 35 256 1,392 Placebo (n) 1,352 152 113 32 254 1,395 MACE and individual outcomes   MACE HR [95% CI] 0.76 [0.58; 1.00] 0.58 [0.25; 1.34] 0.72 [0.23; 2.28] 0.46 [0.08; 2.50] 0.8793 0.67 [0.33; 1.36] 0.74 [0.57; 0.96] 0.7978   CV death HR [95% CI] 0.98 [0.63; 1.50] 0.32 [0.04; 2.85] 1.01 [0.06; 16.20] n/a† 0.8089 0.79 [0.31; 2.00] 1.00 [0.63; 1.59] 0.6521   Non-fatal MI HR [95% CI] 0.69 [0.45; 1.07] 0.97 [0.36; 2.60] 1.37 [0.31; 6.12] 0.31 [0.03; 3.00] 0.6637 0.65 [0.18; 2.31] 0.74 [0.50; 1.10] 0.8562   Non-fatal stroke HR [95% CI] 0.70 [0.42; 1.16] 0.31 [0.04; 2.77] n/a‡ n/a‡ 0.9176 0.73 [0.16; 3.27] 0.60 [0.36; 0.99] 0.7995 Blood pressure at week 104   Systolic BP* ETD (mmHg) [95% CI] −1.92 [−3.09; −0.74] −4.98 [−8.61; 1.35] 4.47 [0.15; 8.79] −11.02 [−18.45; −3.60] 0.0008 −3.22 [−5.93; −0.51] −1.81 [−2.98; −0.64] 0.3489   Diastolic BP* ETD (mmHg) [95% CI] 0.36 [−0.32; 1.04] −1.31 [−3.43; 0.80] −0.07 [−2.56; 2.43] −3.41 [−7.73; 0.92] 0.1871 −0.18 [−1.75; 1.39] 0.16 [−0.52; 0.83] 0.6981 *Treatment difference between semaglutide and placebo (pooled 0.5 and 1.0 mg values for each treatment group) at week 104. †No events in the placebo group; ‡No events in the semaglutide group. BP, blood pressure; CI, confidence interval; ETD, estimated treatment difference; HR, hazard ratio; MACE, major adverse cardiovascular event; MI, myocardial infarction.

Conclusion

Overall there was no evidence of a differential effect of semaglutide on risk reduction in MACE and its components and on BP across race and ethnicity subgroups in this post hoc analysis.

Acknowledgement/Funding

Novo Nordisk A/S

[Bronchoalveolar lavage in hairy cell leukemia with pulmonary infiltration]

We report a 78-year-old male patient suffering from hairy cell leukemia, presenting clinically mainly with dyspnea. Radiology exhibited bilateral ground-glass shadows. In order to prevent pneumonia as a possible side effect due to conventional chemotherapy, it was decided to first treat the patient with rituximab; however, dyspnea persisted. Therefore, bronchoscopy was performed and specimens were sampled for both histological examination and bronchoalveolar lavage (BAL) analysis. BAL showed lymphocytosis (28.7%), and by means of immunocytochemistry a few CD79a+ B‑lymphocytes as well as lymphoid cells positive for the hairy cell marker DBA44 were observed. In addition, molecular study revealed the BRAF V600E mutation. Thus, the findings of BAL were interpreted as lung infiltration by hairy cell leukemia. This result was confirmed by histology. Following a therapy switch to cladribine, a significant improvement was reached. Pulmonary infiltrates by hairy cell leukemia were rarely described. This case represents the first report of hairy cell leukemia diagnosed by means of BAL. It may be difficult to clearly separate between lymphoma infiltration of the lung and medicamentous pneumonitis, but this differential diagnosis can be supported by morphological methods.

Genetics of metabolic traits in Greenlanders: lessons from an isolated population

In this review, we describe the extraordinary population of Greenland, which differs from large outbred populations of Europe and Asia, both in terms of population history and living conditions. Many years in isolation, small population size and an extreme environment have shaped the genetic composition of the Greenlandic population. The unique genetic background combined with the transition from a traditional Inuit lifestyle and diet, to a more Westernized lifestyle, has led to an increase in the prevalence of metabolic conditions like obesity, where the prevalence from 1993 to 2010 has increased from 16.4% to 19.4% among men, and from 13.0% to 25.4% among women, type 2 diabetes and cardiovascular diseases. The genetic susceptibility to metabolic conditions has been explored in Greenlanders, as well as other isolated populations, taking advantage of population-genetic properties of these populations. During the last 10 years, these studies have provided examples of loci showing evidence of positive selection, due to adaption to Arctic climate and Inuit diet, including TBC1D4 and FADS/CPT1A, and have facilitated the discovery of several loci associated with metabolic phenotypes. Most recently, the c.2433-1G>A loss-of-function variant in ADCY3 associated with obesity and type 2 diabetes was described. This locus has provided novel biological insights, as it has been shown that reduced ADCY3 function causes obesity through disrupted function in primary cilia. Future studies of isolated populations will likely provide further genetic as well as biological insights.

Birth weight variants are associated with variable fetal intrauterine growth from 20 weeks of gestation

Fetal intrauterine growth is influenced by complex interactions between the maternal genes, environment and fetal genes. The aim of this study was to assess the effect of GWAS-identified genetic variants associated with birth weight on intrauterine fetal growth in 665 children. Fetal growth was estimated by two-dimensional ultrasound scans at 20, 25 and 32 weeks of gestation and growth trajectories were modeled using mixed linear regression. A genetic risk score (GRS) of birth weight-raising variants was associated with intrauterine growth showing an attenuating effect on the unconditional daily reduction in proportional weight gain of 8.92 × 10-6 percentage points/allele/day (p = 2.0 × 10-4), corresponding to a mean difference of 410 g at 40 weeks of gestation between a child with lowest and highest GRS. Eight variants were independently associated with intrauterine growth throughout the pregnancy, while four variants were associated with fetal growth in the periods 20-25 or 25-32 weeks of gestation, indicating that some variants may act in specific time windows during pregnancy. Four of the intrauterine growth variants were associated with type 2 diabetes, hypertension or BMI in the UK Biobank, which may provide basis for further understanding of the link between intrauterine growth and later risk of metabolic disease.

Maternal and fetal genetic contribution to gestational weight gain

BACKGROUND

Clinical recommendations to limit gestational weight gain (GWG) imply high GWG is causally related to adverse outcomes in mother or offspring, but GWG is the sum of several inter-related complex phenotypes (maternal fat deposition and vascular expansion, placenta, amniotic fluid and fetal growth). Understanding the genetic contribution to GWG could help clarify the potential effect of its different components on maternal and offspring health. Here we explore the genetic contribution to total, early and late GWG.

PARTICIPANTS AND METHODS

A genome-wide association study was used to identify maternal and fetal variants contributing to GWG in up to 10 543 mothers and 16 317 offspring of European origin, with replication in 10 660 mothers and 7561 offspring. Additional analyses determined the proportion of variability in GWG from maternal and fetal common genetic variants and the overlap of established genome-wide significant variants for phenotypes relevant to GWG (for example, maternal body mass index (BMI) and glucose, birth weight).

RESULTS

Approximately 20% of the variability in GWG was tagged by common maternal genetic variants, and the fetal genome made a surprisingly minor contribution to explain variation in GWG. Variants near the pregnancy-specific beta-1 glycoprotein 5 (PSG5) gene reached genome-wide significance (P=1.71 × 10-8) for total GWG in the offspring genome, but did not replicate. Some established variants associated with increased BMI, fasting glucose and type 2 diabetes were associated with lower early, and higher later GWG. Maternal variants related to higher systolic blood pressure were related to lower late GWG. Established maternal and fetal birth weight variants were largely unrelated to GWG.

CONCLUSIONS

We found a modest contribution of maternal common variants to GWG and some overlap of maternal BMI, glucose and type 2 diabetes variants with GWG. These findings suggest that associations between GWG and later offspring/maternal outcomes may be due to the relationship of maternal BMI and diabetes with GWG.

One-carbon metabolism markers are associated with cardiometabolic risk factors

BACKGROUND AND AIMS

Alterations to one-carbon metabolism, especially elevated plasma homocysteine (Hcy), have been suggested to be both a cause and a consequence of the metabolic syndrome (MS). A deeper understanding of the role of other one-carbon metabolites in MS, including s-adenosylmethionine (SAM), s-adenosylhomocysteine (SAH), and the methylation capacity index (SAM:SAH ratio) is required.

METHODS AND RESULTS

118 men and women with MS-risk factors were included in this cross-sectional study and cardiometabolic outcomes along with markers of one-carbon metabolism, including fasting plasma SAM, SAH, Hcy and vitamin B₁₂ concentrations, were analysed. Multiple linear regression models were also used to examine the association between plasma one-carbon metabolites and cardiometabolic health features. We found that fasting plasma concentrations of Hcy, SAM and SAH were all positively correlated with markers of adiposity, including BMI (increase in BMI per 1-SD increase in one-carbon metabolite: 0.92 kg/m² 95% CI (0.28; 1.56), p = 0.005; 0.81 (0.15; 1.47), p = 0.02; 0.67 (-0.01; 1.36), p = 0.05, respectively). Hcy, but not SAM, SAH or SAM:SAH ratio was associated with BMI and body fat percentage after mutual adjustments. SAM concentrations were associated with higher fasting insulin (9.5% 95% CI (0.3; 19.5) per SD increase in SAM, p = 0.04), HOMA-IR (10.8% (0.8; 21.9), p = 0.03) and TNF-α (11.8% (5.0; 19.0), p < 0.001).

CONCLUSION

We found little evidence for associations between SAM:SAH ratio and cardiometabolic variables, but higher plasma concentrations of SAM, SAH and Hcy are related to an overall higher risk of metabolic dysfunctions. The studies were registered at www.clinicaltrials.gov (NCT01719913 &NCT01731366).