Search

A new Brazilian genus of curtain-web spiders, family Dipluridae Simon, 1889, Harpathele gen. nov., is described, with Harpathele gymnognatha comb. nov. (Bertkau, 1880) (Rio de Janeiro state) as its type species. The new genus is a lyrate Diplurinae and it is known only from southeast Brazil. It may be recognized by the relatively small body, maxilla with dorsal transverse suture showing distinct curve at its basal third, a field of numerous long and thin setae above that suture, and a field of small rigid bristles below it, among other characters. Harpathele gymnognatha comb. nov. (Bertkau, 1880) is revalidated and redescribed, with the designation of a neotype and the first description of a male, based on specimens collected in its type locality that match the original description and illustrations, and is pointed as senior synonym of Diplura annectens (Bertkau, 1880). Additionally, two species of the new genus are described: Harpathele cariacica sp. nov., based on females from Espírito Santo state, and Harpathele salinas sp. nov., based on males from Rio de Janeiro state. [ABSTRACT FROM AUTHOR]

Recent advances in nanotechnology design and fabrication have shaped the landscape for the development of ideal cell interfaces based on biomaterials. A holistic evaluation of the requirements for a cell interface is a highly complex task. Biocompatibility is a crucial requirement which is affected by the interface's properties, including elemental composition, morphology, and surface chemistry. This review explores the current state-of-the-art on graphene coatings produced by chemical vapor deposition (CVD) and applied as neural interfaces, detailing the key properties required to design an interface capable of physiologically interacting with neural cells. The interfaces are classified into substrates and scaffolds to differentiate the planar and three-dimensional environments where the cells can adhere and proliferate. The role of specific features such as mechanical properties, porosity and wettability are investigated. We further report on the specific brain-interface applications where CVD graphene paved the way to revolutionary advances in biomedicine. Future studies on the long-term effects of graphene-based materials in vivowill unlock even more potentially disruptive neuro-applications.

Assisted reproductive technologies (ARTs), including in vitro maturation and fertilization (IVF), are increasingly used in human and animal reproduction. Whether these technologies directly affect the rate of de novo mutation (DNM), and to what extent, has been a matter of debate. Here we take advantage of domestic cattle, characterized by complex pedigrees that are ideally suited to detect DNMs and by the systematic use of ART, to study the rate of de novo structural variation (dnSV) in this species and how it is impacted by IVF. By exploiting features of associated de novo point mutations (dnPMs) and dnSVs in clustered DNMs, we provide strong evidence that (1) IVF increases the rate of dnSV approximately fivefold, and (2) the corresponding mutations occur during the very early stages of embryonic development (one- and two-cell stage), yet primarily affect the paternal genome.

We report the generation of an organism-wide catalog of 976,813 cis-acting regulatory elements for the bovine detected by the assay for transposase accessible chromatin using sequencing (ATAC-seq). We regroup these regulatory elements in 16 components by nonnegative matrix factorization. Correlation between the genome-wide density of peaks and transcription start sites, correlation between peak accessibility and expression of neighboring genes, and enrichment in transcription factor binding motifs support their regulatory potential. Using a previously established catalog of 12,736,643 variants, we show that the proportion of single-nucleotide polymorphisms mapping to ATAC-seq peaks is higher than expected and that this is owing to an approximately 1.3-fold higher mutation rate within peaks. Their site frequency spectrum indicates that variants in ATAC-seq peaks are subject to purifying selection. We generate eQTL data sets for liver and blood and show that variants that drive eQTL fall into liver- and blood-specific ATAC-seq peaks more often than expected by chance. We combine ATAC-seq and eQTL data to estimate that the proportion of regulatory variants mapping to ATAC-seq peaks is approximately one in three and that the proportion of variants mapping to ATAC-seq peaks that are regulatory is approximately one in 25. We discuss the implication of these findings on the utility of ATAC-seq information to improve the accuracy of genomic selection.

Supplemental Digital Content is available in the text

One of the first decisions to be made when building a mineral resource model is the definition of geological/geostatistical domains. Cluster analysis is a set of techniques in machine learning that can be especially suited for this matter. In order to compare different approaches, two clustering algorithms were investigated in this study: k-means and the dual-space clustering algorithm. Choosing the most appropriate method and the number of clusters can be challenging and some metrics are needed to support these decisions, including the validation of the spatial distribution of the clusters, which is not always appropriately discussed in the literature. We introduce the use of correlograms of the indicators for that matter. Although clustering techniques can be robust for an application in resource modelling, expert knowledge is still necessary when applying cluster analysis to resource modeling, since final decisions should not be based solely on statistical indexes, but also on experience. In this paper, the proposed methodology was tested in a three-dimensional dataset related to a phosphate/titanium deposit.

This study aimed to characterize the effects of dietary restriction and subsequent re-alimentation on body composition and hepatic gene expression of epigenetic markers of DNA methylation, RNA m6A methylation, and histone acetylation in the liver of postpubertal beef bulls. Twelve Angus × Hereford crossbred bulls (n= 6, 23 ± 0.55 mo [young bulls], 558 ± 6.1 kg; and n= 6, 47 ± 1.2 mo [mature bulls], 740 ± 30.5 kg) were submitted to two dietary regimes per offering of the same hay: low plane of nutrition (90 d) and compensatory growth (90 d). Each animal acted as its own control and were fed Beardless wheat (Triticum aestivum) hay and mineral mix during the trial. Statistical analyses were performed using SAS 9.4 following a pre-post repeated measures design. Bulls in negative energy balance (NEB) decreased (P< 0.001) empty body weight (EBW; 23.1% [−139.1 kg]), empty body fat (EBF; 39.8% [−85.4 kg]), and empty body protein (EBP; 14.9% [−13.5 kg]) and fully recovered at the end of the trial. Body fat accounted for 77.1% of daily changes in body energy status, whereas body protein accounted for only 22.9% (P< 0.001). Relative abundance of epigenetic markers transcripts was analyzed via qPCR. Bulls at NEB tended (P≤ 0.097) to increase gene expression of epigenetic markers of RNA m6A methylation (METTL14, VIRMA, and WTAP) and increased (P≤ 0.050) the gene expression of epigenetic markers of DNA methylation (DNMT3A) and histone-acetylation (SIRT3 and SIRT7). Young bulls had a tendency (P≤ 0.072) of higher RNA m6A methylation, VIRMA, and WTAP than mature bulls. Effect of diet × age interaction was not detected (P≥ 0.137) for METTL14, VIRMA, WTAP, DNMT3A, SIRT3, or SIRT7. Younger bulls tended to have greater RNA m6A methylation levels than mature bulls, indicating that, while contemporaneously fed the same diet during periods of undernourishment followed by compensatory growth, age has an impact on this epigenetic mechanism. In conclusion, metabolic status seems to carry a greater impact on regulating bovine hepatic epigenetic mechanisms that modulate gene transcription, such as DNA methylation and histone acetylation, than on epigenetic mechanisms that regulate gene translation, such as RNA m6A methylation. During periods of undernourishment followed by compensatory growth, body fat pools appear to change more dynamically and are easily detected having a greater impact on epigenetic markers that modulate hepatic gene transcription rather than translation.Epigenetics refers to heritable modifications that regulate gene expression without altering DNA sequence, hence, acting on top of the genes. Epigenetic markers change in response to stressors such as environmental factors, nutritional challenges, among other overlooked players that altogether could drastically impair animal performance. During periods of undernourishment followed by fast weight gain, dynamic changes in body composition, especially fat, appear to trigger an increased action of such physiological markers that modulate hepatic gene expression. Findings of this study unveil epigenetic metabolic pathways that deserve further investigation for proper quantification of potential consequences of metabolic stress on the liver of bovines that suffer significant loss of body weight followed by recovery. The alterations at the molecular level shown in this study provide a picture of silent metabolic changes that have not been detected previously in liver metabolism studies of cattle. Therefore, the impact of nutritional management and metabolic stress may be greater than previously expected and differently controlled than previously assumed.Molecular analyses unveil previously undetected changes on the liver of bulls in response to diet and body weight fluctuation.

Aiming to characterize the effects of nutritional status on epigenetic markers, such as DNA 5-methyl cytosine (mC) methylation and RNA N6-methyladenosine (m6A) methylation, of bovine sperm, 12 Angus × Hereford crossbred breeding bulls were submitted to nutritional changes for a period of 180 d: no change in body weight (BW) (phase 1 = 12 d), BW loss (phase 2 = 78 d), and BW gain (phase 3 = 90 d) in a repeated measures design. Animals were fed Beardless wheat (Triticum aestivum) hay and mineral mix. Statistical analyses were performed using SAS 9.4 (SAS Inst., Cary, NC). Higher levels of RNA m6A (P= 0.004) and DNA methylation (P= 0.007) of spermatic cells were observed at phase 2 compared with phase 1. In phase 3, sperm RNA m6A methylation levels continued to be higher (P= 0.004), whereas the DNA of sperm cells was similar (P= 0.426) compared with phase 1. Growing bulls had a tendency (P= 0.109) of higher RNA m6A methylation levels than mature bulls. Phase 2 altered scrotal circumference (P< 0.001), sperm volume (P= 0.007), sperm total motility (P= 0.004), sperm progressive motility (P= 0.004), total sperm count (P= 0.049), normal sperm (P< 0.001), abnormal sperm (P< 0.001), primary sperm defects (P= 0.039), and secondary sperm defects (P< 0.001). In phase 3, bulls had scrotal circumference, sperm volume, sperm motility, sperm progressive motility, total sperm count, normal and abnormal spermatozoa, and primary and secondary spermatozoa defects similar to phase 1 (P> 0.05). Serum concentrations of insulin-like growth factor-1 and leptin decreased during phase 2 (P= 0.010), while no differences (P> 0.05) were detected between phases 3 and 1; growing bulls tended (P= 0.102) to present higher leptin levels than mature bulls. Specific for mature bulls, DNA methylation was positively correlated with leptin concentration (0.569, P= 0.021), whereas for young bulls, DNA methylation was positively correlated with abnormal spermatozoa (0.824, P= 0.006), primary spermatozoa defect (0.711, P= 0.032), and secondary spermatozoa defect (0.661, P= 0.052) and negatively correlated with normal spermatozoa (−0.824, P= 0.006), total sperm count (−0.702, P= 0.035), and sperm concentration (−0.846, P= 0.004). There was no significant correlation (P> 0.05) between RNA m6A and hormones and semen traits. In conclusion, the nutritional status of breeding bulls alters epigenetic markers, such as DNA methylation and RNA m6A methylation, in sperm, and the impact of change seems to be age dependent. These markers may serve as biomarkers of sperm quality and fertility of bulls in the future. Detrimental effects on sperm production and seminal quality are observed at periods and places when and where environmental and nutritional limitations are a year-round reality and may carry hidden players that may influence a lifetime of underperformance.