Correction to: Toxicity prediction and assessment of an environmentally realistic pesticide mixture to Daphnia magna and Raphidocelis subcapitata

Acknowledgements This work was supported by LEAF (UID/AGR/04129/2013) and CESAM (UID/AMB/50017/2013) from FCT/MEC through national funds, and the cofunding by FEDER (POCI-01-0145-FEDER-007638), within the PT2020 Partnership Agreement and Compete2020.

Toxicity prediction and assessment of an environmentally realistic pesticide mixture to Daphnia magna and Raphidocelis subcapitata

In a regulatory perspective addressing the cumulative effect of co-occurring chemicals is the first and most important step in providing a more realistic hazard assessment of chemical cocktails to both man and environment. This study was conducted to show if joint effects on the immobilisation of the crustacean Daphnia magna and on the growth inhibition of algae Raphidocelis subcapitata follow additivity (concentration addition (CA) or independent action (IA) predictions) or if there is an interaction between chemicals in the organisms upon exposure to an environmentally realistic mixture of chlorpyrifos and terbuthylazine, with expected different molecular sites of action. A pattern of antagonism at lower doses and synergism at higher doses was found for acute immobility data, while no deviation from the additive conceptual models was observed in the algae inhibition test. Results in relation to the relevant set of regulatory acceptable concentrations (RACs) and environmental quality standards (EQSs) derived for individual chlorpyrifos and terbuthylazine were evaluated.

Differing molecular response of young and advanced maternal age human oocytes to IVM

STUDY QUESTION

What effect does maternal age have on the human oocyte's molecular response to in vitro oocyte maturation?

SUMMARY ANSWER

Although polyadenylated transcript abundance is similar between young and advanced maternal age (AMA) germinal vesicle (GV) oocytes, metaphase II (MII) oocytes exhibit a divergent transcriptome resulting from a differential response to in vitro oocyte maturation.

WHAT IS KNOWN ALREADY

Microarray studies considering maternal age or maturation stage have shown that either of these factors will affect oocyte polyadenylated transcript abundance in human oocytes. However, studies considering both human oocyte age and multiple stages simultaneously are limited to a single study that examined transcript levels for two genes by qPCR. Thus, polyadenylated RNA sequencing (RNA-Seq) could provide novel insight into age-associated aberrations in gene expression in GV and MII oocytes.

STUDY DESIGN, SIZE, DURATION

The effect of maternal age (longitudinal analysis) on polyadenylated transcript abundance at different stages was analyzed by examining single GV and single in vitro matured MII oocytes derived from five young (YNG; < 30 years; average age 26.8; range 20-29) and five advanced maternal age (AMA; ≥40 years; average age 41.6 years; range 40-43 years) patients. Thus, a total of 10 YNG (5 GV and 5 MII) and 10 AMA (5 GV and 5 MII) oocytes were individually processed for RNA-Seq analysis.

PARTICIPANTS/MATERIALS, SETTINGS, METHODS

Patients undergoing infertility treatment at the Colorado Center for Reproductive Medicine (Lone Tree, CO, USA) underwent ovarian stimulation with FSH and received hCG for final follicular maturation prior to ultrasound guided oocyte retrieval. Unused GV oocytes obtained at retrieval were donated for transcriptome analysis. Single oocytes were stored (at -80°C in PicoPure RNA Extraction Buffer; Thermo Fisher Scientific, USA) immediately upon verification of immaturity or after undergoing in vitro oocyte maturation (24 h incubation), representing GV and MII samples, respectively. After isolating RNA and generating single oocyte RNA-Seq libraries (SMARTer Ultra Low Input RNA HV kit; Clontech, USA), Illumina sequencing (100 bp paired-end reads on HiSeq 2500) and bioinformatics analysis (CLC Genomics Workbench, DESeq2, weighted gene correlation network analysis (WGCNA), Ingenuity Pathway Analysis) were performed.

MAIN RESULTS AND THE ROLE OF CHANCE

A total of 12 770 genes were determined to be expressed in human oocytes (reads per kilobase per million mapped reads (RPKM) > 0.4 in at least three of five replicates for a minimum of one sample type). Differential gene expression analysis between YNG and AMA oocytes (within stage) identified 1 and 255 genes that significantly differed (adjusted P < 0.1 and log2 fold change >1) in polyadenylated transcript abundance for GV and MII oocytes, respectively. These genes included CDK1, NLRP5 and PRDX1, which have been reported to affect oocyte developmental potential. Despite the similarity in transcript abundance between GV oocytes irrespective of age, divergent expression patterns emerged during oocyte maturation. These age-specific differentially expressed genes were enriched (FDR < 0.05) for functions and pathways associated with mitochondria, cell cycle and cytoskeleton. Gene modules generated by WGCNA (based on gene expression) and patient traits related to oocyte quality (e.g. age and blastocyst development) were correlated (P < 0.05) and enriched (FDR < 0.05) for functions and pathways associated with oocyte maturation.

LARGE SCALE DATA

Raw data from this study can be accessed through GSE95477.

LIMITATIONS, REASONS FOR CAUTION

The human oocytes used in the current study were obtained from patients with varying causes of infertility (e.g. decreased oocyte quality and oocyte quality-independent factors), possibly affecting oocyte gene expression. Oocytes in this study were retrieved at the GV stage following hCG administration and the MII oocytes were derived by IVM of patient oocytes. Although the approach has the benefit of identifying intrinsic differences between samples, it may not be completely representative of in vivo matured oocytes.

WIDER IMPLICATIONS OF THE FINDINGS

Transcriptome profiles of YNG and AMA oocytes, particularly at the MII stage, suggest that aberrant transcript abundance may contribute to the age-associated decline in fertility.

STUDY FUNDING/COMPETING INTEREST(S)

J.M.R. was supported by an Austin Eugene Lyons Fellowship awarded by the University of California, Davis. The Eunice Kennedy Shriver National Institute of Child Health and Human Development of the National Institutes of Health (awarded to P.J.R.; R01HD070044) and the Fertility Laboratories of Colorado partly supported the research presented in this manuscript.

The last frontier: Coupling technological developments with scientific challenges to improve hazard assessment of deep-sea mining

The growing economic interest in the exploitation of mineral resources on deep-ocean beds, including those in the vicinity of sensitive-rich habitats such as hydrothermal vents, raise a mounting concern about the damage that such actions might originate to these poorly-know ecosystems, which represent millions of years of evolution and adaptations to extreme environmental conditions. It has been suggested that mining may cause a major impact on vent ecosystems and other deep-sea areas. Yet, the scale and the nature of such impacts are unknown at present. Hence, building upon currently available scientific information it is crucial to develop new cost-effective technologies embedded into rigorous operating frameworks. The forward-thinking provided here will assist in the development of new technologies and tools to address the major challenges associated with deep sea-mining; technologies for in situ and ex situ observation and data acquisition, biogeochemical processes, hazard assessment of deep-sea mining to marine organisms and development of modeling tools in support of risk assessment scenarios. These technological developments are vital to validate a responsible and sustainable exploitation of the deep-sea mineral resources, based on the precautionary principle.

Apolipoprotein B and angiotensin-converting enzyme polymorphisms and aerobic interval training: randomized controlled trial in coronary artery disease patients

Physical training has been strongly recommended as a non-pharmacological treatment for coronary artery disease (CAD). Genetic polymorphisms have been studied to understand the biological variability in response to exercise among individuals. This study aimed to verify the possible influence of apolipoprotein B (ApoB: rs1042031 and rs693) and angiotensin-converting enzyme (ACE-ID: rs1799752) genotypes on the lipid profile and functional aerobic capacity, respectively, after an aerobic interval training (AIT) program in patients with CAD and/or cardiovascular risk factors. Sixty-six men were randomized and assigned to trained group (n=32) or control group (n=34). Cardiopulmonary exercise test was performed to determine the ventilatory anaerobic threshold (VAT) from cardiorespiratory variables. The AIT program, at an intensity equivalent to %VAT (70-110%), was conducted three times a week for 16 weeks. ApoB gene polymorphisms (-12669C>T (rs1042031) and -7673G>A (rs693)) were identified by real-time polymerase chain reaction (PCR). I/D polymorphism in the ACE gene (rs1799752) was identified through PCR and fragment size analysis. After 16 weeks, low-density lipoprotein (LDL) levels increased in the trained and control groups with the GA+AA genotype (-7673G>A) of the ApoB gene. Trained groups with ACE-II and ACE-ID genotypes presented an increase in oxygen consumption (VO2VAT) and power output after the AIT program. The presence of the ACE I-allele was associated with increased aerobic functional capacity after the AIT program. Increased LDL levels were observed over time in patients with the -7673G>A polymorphism of the ApoB gene. Trial Registration Information: ClinicalTrials.gov: NCT02313831.

Diels–Alder Reactions of 1,2-Dihydropyridines: An Efficient Tool for the Synthesis of Isoquinuclidines

The Diels–Alder reaction of 1,2-dihydropyridines with different dienophiles is a well-established and straightforward method for the synthesis of isoquinuclidines. Nevertheless, the enantioselective preparation of isoquinuclidines using organocatalysts or organometallic catalysts is rather unexplored. This succinct review offers readers an overall perspective of the most important recent developments and concepts related to this topic.

1 Introduction

2 Asymmetric Diels–Alder Reaction of 1,2-Dihydropyridines

2.1 Transition-Metal-Catalyzed Reactions

2.2 Organocatalyzed Reactions

3 Diels–Alder Reaction of 1,2-Dihydropyridines in the Synthesis of Biologically Valuable Compounds

4 Conclusion

One-Pot Synthesis of Isoquinuclidines via 2,6-Diaryl-1,2-dihydropyridines using (E,E)-Cinnamylideneacetophenones as Templates

Diastereoselective Diels–Alder reactions of 2,6-diaryl-1,2-dihydropyridines with N-methylmaleimide afford highly substituted isoquinuclidines in good chemical yield (30–50%). This sequential one-pot synthesis is performed under microwave irradiation and involves, primarily, the synthesis of 2,6-diaryl-1,2-dihydropyridines by a 6π-azaelectrocyclisation involving an intermediate α,β,γ,δ-di-unsaturated imine, obtained by condensation of (E,E)-cinnamylideneacetophenones with amines. This procedure easily converts unstable 2,6-diaryl-1,2-dihydropyridines into, otherwise inaccessible, isoquinuclidines without any kind of manipulation.

Multidisciplinary oral rehabilitation in partially edentulous adult patients with malocclusion: A cross-sectional survey study

Background

A cross-sectional survey was conducted to gather information regarding the opinion of Brazilian specialists in both orthodontics and implantology on multidisciplinary oral rehabilitation in partially edentulous patients with malocclusion.

Material and Methods

A total of 305 specialists participated in a telephone survey and answered an ad hoc 10-item questionnaire, including the request of total skull cone-beam tomographies (CBCT) and the use of 3D digital planning software, the best moment of treatment to place dental implants, and the integration of orthodontics in implantology.

Results

Most participants did not request CBCT (90.8%) or 3D digital planning software images (92.3%) to diagnose and plan multidisciplinary oral rehabilitation. By contrast, 91.1% of participants would use an already dental implant as anchorage for orthodontics, 73.8% had already used implants for this purpose, 47.9% selected 4 months as the waiting time between implant placement and its use as anchorage, and 58.4% had already placed dental implants having in mind using them as anchorage for orthodontics and anticipating the oral rehabilitation process. Moreover, 93.4% of participants stated to avoid applying orthodontic forces in implants with unfavourable prognosis. A total of 67.9% of participants got the degree of specialist in Orthodontics before that of specialist in Implantology. The main reason for obtaining the other specialty degree was to be able to thoroughly exercise the two specialties.

Conclusions

The use of technological advances, such as CBCT and 3D digital planning software was limited. Most dental specialists would wait the osseointegration recommended time before applying orthodontic forces and thus using them as anchorage for orthodontics. The majority of interviewed dentists sought the other specialty to acquire multidisciplinary knowledge.

Key words:Cross-sectional study, orthodontics, implantology, partially edentulous, malocclusion, oral rehabilitation.

Ovarian steroids, oxytocin, and tumor necrosis factor modulate equine oviduct function

The oviduct plays important roles in the early reproductive process. The aim of this study was to evaluate gene transcription and protein expression of progesterone receptor (PGR), estrogen receptors 1 (ESR1) and 2 (ESR2); oxytocin receptor (OXTR); prostaglandin F2α synthase (AKR1C3), and prostaglandin E2 synthase (Ptges) in mare oviduct in different estrous cycle stages. Estradiol (E₂), progesterone (P₄), oxytocin (OXT), and tumor necrosis factor α (TNF) effect on in vitro PGE₂ and prostaglandin F2α (PGF_2α) secretion by equine oviduct explants or by oviductal epithelial cells (OECs) were also assessed. During the breeding season, oviduct tissue was obtained post mortem from cyclic mares. Protein of ESR1, ESR2, PGR, AKR1C3, and Ptges was present in OECs, whereas OXTR was shown in oviduct stroma. In follicular phase, protein expression of ESR1, ESR2, PGR, and OXTR increased in oviduct explants (P < 0.05), whereas no estrous cycle effect was noted for AKR1C3 or Ptges. In follicular phase, mRNA transcription was upregulated for Pgr but downregulated for Oxtr, Ptges, and Akr1c3 (P < 0.05). Nevertheless, Esr1 and Esr2 mRNA levels did not change with the estrous cycle. In the ampulla, Esr1, Esr2, and Oxtr mRNA transcription increased, but not for Pgr or Ptges. In contrast, Akr1c3 mRNA level was upregulated in the infundibulum (P < 0.05). In follicular phase, E₂, P₄, and OXT downregulated PGE₂ production by OEC (P < 0.05), but no difference was observed in mid-luteal phase. Explants production of PGE₂ rose when treated with OXT in follicular phase; with TNF or OXT in early luteal phase; or with TNF, OXT, or P₄ in mid-luteal phase. PGF_2α production by OEC was downregulated by all treatments in follicular phase but upregulated in mid-luteal phase (P < 0.05). Oviduct explants PGF_2α production was stimulated by TNF or OXT in all estrous cycle phases. In conclusion, this work has shown that ESR1, ESR2, OXTR, Ptges, and AKRLC3 gene transcription and/or translation is estrous cycle dependent and varies with oviduct portion (infundibulum vs ampulla) and cell type. Ovarian steroid hormones, OXT and TNF stimulation of PGF_2α and/or PGE₂ production is also estrous cycle dependent and varies in the different portions of mare oviduct. Differential transcription level and protein localization in various portions of the oviduct throughout the estrous cycle, as well as PG production, suggest coordinated physiologic actions and mechanisms of steroid hormones, OXT, and TNF in the equine oviduct.

Lactadherin is a candidate oviduct Lewis X trisaccharide receptor on porcine spermatozoa

A recent study has demonstrated that porcine spermatozoa recognize with high affinity carbohydrate structures containing Lewis X motifs. Sperm adhesion to Lewis X is proposed to mediate sperm binding to the oviduct epithelium to form a reservoir. The objective of this study was to identify Lewis X-binding proteins from porcine spermatozoa as candidate receptors for oviduct glycans. To identify low-abundance proteins typically masked by proteins originating from seminal fluid, Lewis X candidate receptors were enriched from cauda epididymal boar spermatozoa. Plasma membrane preparations from cauda epididymal spermatozoa were subjected to RP-HPLC and glycan blotting assays to isolate and detect proteins that bind Lewis X. Following bottom-up LC-MS/MS analysis, among the two bands that bound sulfated Lewis X, ADAM5, which spermatozoa, was confidently identified. ADAM family members have been established as contributors to sperm entry into the oviduct. A second sulfated Lewis X-binding protein identified was the peripheral membrane protein lactadherin (also known as P47, SED1 and MFG-E8 in different species). The interaction between Lewis X and lactadherin was functionally important because competitive inhibition by soluble recombinant lactadherin reduced sperm binding to the oviduct epithelium. Furthermore, far-western blotting demonstrated that purified lactadherin could bind oviduct cells. In summary, these findings reveal that, in addition to the previously reported glycan affinity of accessory gland proteins that adhere to spermatozoa, multiple proteins intrinsic to spermatozoa have affinity for a specific oviduct glycan. Further, in addition to binding to the zona pellucida, lactadherin is now implicated in binding to oviduct glycans to promote formation of the sperm reservoir.

Abstract P1-04-09: The missing link: Chemicals, epigenetics and breast cancer

This abstract was not presented at the symposium.

Abstract P6-05-03: Investigating the effects of low-dose mixtures of environmental contaminants on breast cancer initiation

This abstract was not presented at the symposium.