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Compared to most mammals, human pregnancy is unusual in that it involves chromosomally diverse embryos, cyclical breakdown and regeneration of the uterine mucosa, and intimate integration of fetal and maternal cells at the uteroplacental interface. Not surprisingly, pregnancy often falters in early gestation. Whether these losses result in clinical miscarriages depends on the origins and impacts of chromosomal errors on fetal development and the ability of the decidualizing endometrium to engage in embryo biosensing and selection. Aneuploidy originating in oocytes during meiosis drives the age-related risk of miscarriage. By contrast, the frequency of endometrial cycles with an impaired decidual response may account for the stepwise increase in miscarriage rates with each pregnancy loss independently of maternal age. Additional physiological mechanisms operate in early gestation to ensure that most failing pregnancies are lost before vascular maternal-fetal connections are established by the end of the first trimester. Here, we summarise how investigations into the mechanisms that cause miscarriage led to new insights into the processes that govern maternal selection of human embryos in early gestation.

Since its initial release in 2000, the human reference genome has covered only the euchromatic fraction of the genome, leaving important heterochromatic regions unfinished. Addressing the remaining 8% of the genome, the Telomere-to-Telomere (T2T) Consortium presents a complete 3.055 billion–base pair sequence of a human genome, T2T-CHM13, that includes gapless assemblies for all chromosomes except Y, corrects errors in the prior references, and introduces nearly 200 million base pairs of sequence containing 1956 gene predictions, 99 of which are predicted to be protein coding. The completed regions include all centromeric satellite arrays, recent segmental duplications, and the short arms of all five acrocentric chromosomes, unlocking these complex regions of the genome to variational and functional studies.

Chromosomal mosaicism, or the co-existence of cells with different chromosomal content, is a phenomenon that has been documented in human embryos for three decades. Early versions of preimplantation genetic testing (PGT-A) did not measure mosaicism, either because typically only a single cell was assessed, or because the technique could not accurately identify it. While this led to a straightforward diagnosis (an embryo was considered either normal or abnormal), it simply avoided the matter and in hindsight may have led to numerous misdiagnoses with negative clinical consequences. Modern PGT-A evaluates a multicellular biopsy with technologies capable of recognizing intermediate copy number signals for chromosomes or sub-chromosomal regions. We are therefore inevitably confronted with the issue of mosaicism and the challenge of managing embryos producing such results in the clinic. Here we discuss recent data showing that not only mosaicism in general, but specific features of mosaicism detected with PGT-A are associated with variable clinical outcomes. The conclusion is evident: mosaicism should be considered for more informed and improved embryo selection in the clinic.

Background Physical punishment at home and in schools is widespread around the world. Systematic reviews and meta-analyses have synthesized evidence, mostly from high-income countries (HICs), showing that physical punishment relates to multiple detrimental individual outcomes. Yet, less work has been done to synthesize the evidence on the association between physical punishment at home and schools and child, adolescent, and adult outcomes in low- and middle-income countries (LMICs), where more than 90% of children live and physical punishment is most socially normative and prevalent. In this manuscript, we present a protocol for a systematic review and meta-analysis on the characteristics of the research, associations, and variation in associations, between physical punishment at home and in schools and child, adolescent, and adult outcomes in LMICs. Methods We will conduct a review of studies published in peer-reviewed journals using quantitative methods to assess the association between physical punishment in childhood and/or adolescence and individual outcomes in LMICs. We will search for studies in 10 different databases using keywords in English, Spanish, Portuguese, Arabic, and Chinese related to physical punishment. We will extract qualitative data from the studies and the statistics needed to transform all study-level effect sizes into standardized mean difference effect sizes. For the analyses, we will employ multi-level meta-analyses to use multiple effect sizes per study and leverage within-study variation as well as between study variation using moderation analysis. Besides the meta-analyses, we will also conduct a narrative synthesis of the findings. Discussion The proposed systematic review and meta-analysis will provide timely evidence to inform global research, policy, and practice on the links between physical punishment and lifelong individual outcomes. Systematic review registration PROSPERO CRD42022347346

Growth differentiation factor 8 (GDF8), a.k.a. myostatin, is a member of the larger TGFβ superfamily of signaling ligands. GDF8 has been well characterized as a negative regulator of muscle mass. After synthesis, GDF8 is held latent by a noncovalent complex between the N-terminal prodomain and the signaling ligand. Activation of latent GDF8 requires proteolytic cleavage of the prodomain at residue D99 by a member of the tolloid family of metalloproteases. While tolloid proteases cleave multiple substrates, they lack a conserved consensus sequence. Here, we investigate the tolloid cleavage site of the GDF8 prodomain to determine what residues contribute to tolloid recognition and subsequent proteolysis. Using sequential alanine mutations, we identified several residues adjacent to the scissile bond, including Y94, that when mutated, abolish tolloid-mediated activation of latent GDF8. Using the astacin domain of Tll1 (Tolloid Like 1) we determined that prodomain mutants were more resistant to proteolysis. Purified latent complexes harboring the prodomain mutations, D92A and Y94A, impeded activation by tolloid but could be fully activated under acidic conditions. Finally, we show that co-expression of GDF8 WT with prodomain mutants that were tolloid resistant, suppressed GDF8 activity. Taken together our data demonstrate that residues towards the N-terminus of the scissile bond are important for tolloid-mediated activation of GDF8 and that the tolloid-resistant version of the GDF8 prodomain can function dominant negative to WT GDF8.

Compared to its predecessors, the Telomere-to-Telomere CHM13 genome adds nearly 200 million base pairs of sequence, corrects thousands of structural errors, and unlocks the most complex regions of the human genome for clinical and functional study. We show how this reference universally improves read mapping and variant calling for 3202 and 17 globally diverse samples sequenced with short and long reads, respectively. We identify hundreds of thousands of variants per sample in previously unresolved regions, showcasing the promise of the T2T-CHM13 reference for evolutionary and biomedical discovery. Simultaneously, this reference eliminates tens of thousands of spurious variants per sample, including reduction of false positives in 269 medically relevant genes by up to a factor of 12. Because of these improvements in variant discovery coupled with population and functional genomic resources, T2T-CHM13 is positioned to replace GRCh38 as the prevailing reference for human genetics.

This study examined whether child diet and mother-child interactions mediated the effects of a responsive stimulation and nutrition intervention delivered from 2009 to 2012 to 1324 children aged 0-24 months living in rural Pakistan. Results showed that the intervention improved children's cognitive, language and motor development through child diet and mother-child interactions. Although the intervention did not improve child growth or socio-emotional development, we observed positive indirect effects on child growth via child diet and on socio-emotional development via both child diet and mother-child interactions. In addition, child diet emerged as a shared mechanism to improve both child growth and development, whereas mother-child interactions emerged as a distinct mechanism to improve child development. Nevertheless, our results suggest the two mechanisms were mutually reinforcing and that interventions leveraging both mechanisms are likely to be more effective at improving child outcomes than interventions leveraging only one of these mechanisms.

Extra or missing chromosomes—a phenomenon termed aneuploidy—frequently arises during human meiosis and embryonic mitosis and is the leading cause of pregnancy loss, including in the context of in vitro fertilization (IVF). While meiotic aneuploidies affect all cells and are deleterious, mitotic errors generate mosaicism, which may be compatible with healthy live birth. Large-scale abnormalities such as triploidy and haploidy also contribute to adverse pregnancy outcomes, but remain hidden from standard sequencing-based approaches to preimplantation genetic testing (PGT-A). The ability to reliably distinguish meiotic and mitotic aneuploidies, as well as abnormalities in genome-wide ploidy may thus prove valuable for enhancing IVF outcomes. Here, we describe a statistical method for distinguishing these forms of aneuploidy based on analysis of low-coverage whole-genome sequencing data, which is the current standard in the field. Our approach overcomes the sparse nature of the data by leveraging allele frequencies and linkage disequilibrium (LD) measured in a population reference panel. The method, which we term LD-informed PGT-A (LD-PGTA), retains high accuracy down to coverage as low as 0.05× and at higher coverage can also distinguish between meiosis I and meiosis II errors based on signatures spanning the centromeres. LD-PGTA provides fundamental insight into the origins of human chromosome abnormalities, as well as a practical tool with the potential to improve genetic testing during IVF.Significance StatementWhole chromosome gains and losses—termed aneuploidies—are the leading cause of human pregnancy loss and congenital disorders. Recent work has demonstrated that in addition to harmful meiotic aneuploidies, mitotic aneuploidies (which lead to mosaic embryos harboring cells with different numbers of chromosomes) may also be common in preimplantation embryos but potentially compatible with healthy birth. Here we developed and tested a method for distinguishing these forms of aneuploidy using genetic testing data from 8154 IVF embryos. We re-classified embryos based on signatures of meiotic and mitotic error, while also revealing lethal forms of chromosome abnormality that were hidden to existing approaches. Our method complements standard protocols for preimplantation and prenatal genetic testing, while offering insight into the biology of early development.

Large genomic insertions, deletions, and inversions are a potent source of functional and fitness-altering variation, but are challenging to resolve with short-read DNA sequencing alone. While recent long-read sequencing technologies have greatly expanded the catalog of structural variants (SVs), their costs have so far precluded their application at population scales. Given these limitations, the role of SVs in human adaptation remains poorly characterized. Here, we used a graph-based approach to genotype 107,866 long-read-discovered SVs in short-read sequencing data from diverse human populations. We then applied an admixture-aware method to scan these SVs for patterns of population-specific frequency differentiation—a signature of local adaptation. We identified 220 SVs exhibiting extreme frequency differentiation, including several SVs that were among the lead variants at their corresponding loci. The top two signatures traced to separate insertion and deletion polymorphisms at the immunoglobulin heavy chain locus, together tagging a 325 Kbp haplotype that swept to high frequency and was subsequently fragmented by recombination. Alleles defining this haplotype are nearly fixed (60-95%) in certain Southeast Asian populations, but are rare or absent from other global populations composing the 1000 Genomes Project. Further investigation revealed that the haplotype closely matches with sequences observed in two of three high-coverage Neanderthal genomes, providing strong evidence of a Neanderthal-introgressed origin. This extraordinary episode of positive selection, which we infer to have occurred between 1700 and 8400 years ago, corroborates the role of immune-related genes as prominent targets of adaptive archaic introgression. Our study demonstrates how combining recent advances in genome sequencing, genotyping algorithms, and population genetic methods can reveal signatures of key evolutionary events that remained hidden within poorly resolved regions of the genome.

Growth differentiation factor 8 (GDF8; also known as myostatin) and GDF11 are closely related members of the transforming growth factor β (TGF-β) family. GDF8 strongly and negatively regulates skeletal muscle growth, and GDF11 has been implicated in various age-related pathologies such as cardiac hypertrophy. GDF8 and GDF11 signaling activities are controlled by the extracellular protein antagonists follistatin; follistatin-like 3 (FSTL3); and WAP, follistatin/kazal, immunoglobulin, Kunitz, and netrin domain–containing (WFIKKN). All of these proteins contain a follistatin domain (FSD) important for ligand binding and antagonism. Here, we investigated the structure and function of the FSD from murine WFIKKN2 and compared it with the FSDs of follistatin and FSTL3. Using native gel shift and surface plasmon resonance analyses, we determined that the WFIKKN2 FSD can interact with both GDF8 and GDF11 and block their interactions with the type II receptor activin A receptor type 2B (ActRIIB). Further, we solved the crystal structure of the WFIKKN2 FSD to 1.39 Å resolution and identified surface-exposed residues that, when substituted with alanine, reduce antagonism of GDF8 in full-length WFIKKN2. Comparison of the WFIKKN2 FSD with those of follistatin and FSTL3 revealed differences in both the FSD structure and position of residues within the domain that are important for ligand antagonism. Taken together, our results indicate that both WFIKKN and follistatin utilize their FSDs to block the type II receptor but do so via different binding interactions.

Miscarriage is generally defined as the loss of a pregnancy before viability. An estimated 23 million miscarriages occur every year worldwide, translating to 44 pregnancy losses each minute. The pooled risk of miscarriage is 15·3% (95% CI 12·5–18·7%) of all recognised pregnancies. The population prevalence of women who have had one miscarriage is 10·8% (10·3–11·4%), two miscarriages is 1·9% (1·8–2·1%), and three or more miscarriages is 0·7% (0·5–0·8%). Risk factors for miscarriage include very young or older female age (younger than 20 years and older than 35 years), older male age (older than 40 years), very low or very high body-mass index, Black ethnicity, previous miscarriages, smoking, alcohol, stress, working night shifts, air pollution, and exposure to pesticides. The consequences of miscarriage are both physical, such as bleeding or infection, and psychological. Psychological consequences include increases in the risk of anxiety, depression, post-traumatic stress disorder, and suicide. Miscarriage, and especially recurrent miscarriage, is also a sentinel risk marker for obstetric complications, including preterm birth, fetal growth restriction, placental abruption, and stillbirth in future pregnancies, and a predictor of longer-term health problems, such as cardiovascular disease and venous thromboembolism. The costs of miscarriage affect individuals, health-care systems, and society. The short-term national economic cost of miscarriage is estimated to be £471 million per year in the UK. As recurrent miscarriage is a sentinel marker for various obstetric risks in future pregnancies, women should receive care in preconception and obstetric clinics specialising in patients at high risk. As psychological morbidity is common after pregnancy loss, effective screening instruments and treatment options for mental health consequences of miscarriage need to be available. We recommend that miscarriage data are gathered and reported to facilitate comparison of rates among countries, to accelerate research, and to improve patient care and policy development.

Background Growth/differentiation factor 8 (GDF8) and GDF11 are two highly similar members of the transforming growth factor β (TGFβ) family. While GDF8 has been recognized as a negative regulator of muscle growth and differentiation, there are conflicting studies on the function of GDF11 and whether GDF11 has beneficial effects on age-related dysfunction. To address whether GDF8 and GDF11 are functionally identical, we compared their signaling and structural properties. Results Here we show that, despite their high similarity, GDF11 is a more potent activator of SMAD2/3 and signals more effectively through the type I activin-like receptor kinase receptors ALK4/5/7 than GDF8. Resolution of the GDF11:FS288 complex, apo-GDF8, and apo-GDF11 crystal structures reveals unique properties of both ligands, specifically in the type I receptor binding site. Lastly, substitution of GDF11 residues into GDF8 confers enhanced activity to GDF8. Conclusions These studies identify distinctive structural features of GDF11 that enhance its potency, relative to GDF8; however, the biological consequences of these differences remain to be determined. Electronic supplementary material The online version of this article (doi:10.1186/s12915-017-0350-1) contains supplementary material, which is available to authorized users.

An increasingly important scenario in population genetics is when a large cohort has been genotyped using a low-resolution approach (e.g., microarrays, exome capture, short-read WGS), from which a few individuals are resequenced using a more comprehensive approach, especially long-read sequencing. The subset of individuals selected should ensure that the captured genetic diversity is fully representative and includes variants across all subpopulations. For example, human variation has historically focused on individuals with European ancestry, but this represents a small fraction of the overall diversity. Addressing this, SVCollector identifies the optimal subset of individuals for resequencing by analyzing population-level VCF files from low-resolution genotyping studies. It then computes a ranked list of samples that maximizes the total number of variants present within a subset of a given size. To solve this optimization problem, SVCollector implements a fast, greedy heuristic and an exact algorithm using integer linear programming. We apply SVCollector on simulated data, 2504 human genomes from the 1000 Genomes Project, and 3024 genomes from the 3000 Rice Genomes Project and show the rankings it computes are more representative than alternative naive strategies. When selecting an optimal subset of 100 samples in these cohorts, SVCollector identifies individuals from every subpopulation, whereas naive methods yield an unbalanced selection. Finally, we show the number of variants present in cohorts selected using this approach follows a power-law distribution that is naturally related to the population genetic concept of the allele frequency spectrum, allowing us to estimate the diversity present with increasing numbers of samples.

The Bone Morphogenetic Proteins (BMPs) are the largest class signaling molecules within the greater Transforming Growth Factor Beta (TGFβ) family, and are responsible for a wide array of biological functions, including dorsal-ventral patterning, skeletal development and maintenance, as well as cell homeostasis. As such, dysregulation of BMPs results in a number of diseases, including fibrodysplasia ossificans progressiva (FOP) and pulmonary arterial hypertension (PAH). Therefore, understanding BMP signaling and regulation at the molecular level is essential for targeted therapeutic intervention. This review discusses the recent advances in the structural and biochemical characterization of BMPs, from canonical ligand-receptor interactions to co-receptors and antagonists. This work aims to highlight how BMPs differ from other members of the TGFβ family, and how that information can be used to further advance the field. Lastly, this review discusses several gaps in the current understanding of BMP structures, with the aim that discussion of these gaps will lead to advancements in the field.

Differences in gene expression are thought to account for most phenotypic differences within and between species. Consequently, gene expression is a powerful lens through which to study divergence between modern humans and our closest evolutionary relatives, the Neanderthals and Denisovans. Such insights complement biological knowledge gleaned from the fossil record, while also revealing general features of the mode and tempo of regulatory evolution. Because of the degradation of ancient RNA, gene expression profiles of archaic hominins must be studied by indirect means. As such, conclusions drawn from these studies are often laden with assumptions about the genetic architecture of gene expression, the complexity of which is increasingly apparent. Despite these challenges, rapid technical and conceptual advances in the fields of ancient genomics, functional genomics, statistical genomics, and genome engineering are revolutionizing understanding of hominin gene expression evolution.

Aneuploidy is the leading contributor to pregnancy loss, congenital anomalies, and in vitro fertilization (IVF) failure in humans. Although most aneuploid conceptions are thought to originate from meiotic division errors in the female germline, quantitative studies that link the observed phenotypes to underlying error mechanisms are lacking. In this study, we developed a mathematical modeling framework to quantify the contribution of different mechanisms of erroneous chromosome segregation to the production of aneuploid eggs. Our model considers the probabilities of all possible chromosome gain/loss outcomes that arise from meiotic errors, such as nondisjunction (NDJ) in meiosis I and meiosis II, and premature separation of sister chromatids (PSSC) and reverse segregation (RS) in meiosis I. To understand the contributions of different meiotic errors, we fit our model to aneuploidy data from 11,157 blastocyst-stage embryos. Our best-fitting model captures several known features of female meiosis, for instance, the maternal age effect on PSSC. More importantly, our model reveals previously undescribed patterns, including an increased frequency of meiosis II errors among eggs affected by errors in meiosis I. This observation suggests that the occurrence of NDJ in meiosis II is associated with the ploidy status of an egg. We further demonstrate that the model can be used to identify IVF patients who produce an extreme number of aneuploid embryos. The dynamic nature of our mathematical model makes it a powerful tool both for understanding the relative contributions of mechanisms of chromosome missegregation in human female meiosis and for predicting the outcomes of assisted reproduction.

Less than half of human zygotes survive to live birth, primarily due to aneuploidies of meiotic or mitotic origin. Mitotic errors lead to chromosomal mosaicism, defined by multiple cell lineages with distinct chromosome complements. The incidence and fitness consequences of chromosomal mosaicism in human embryos remain controversial, with most previous studies based on bulk DNA assays or comparisons of multiple biopsies of a few embryonic cells. Single-cell genomic data provide an opportunity to quantify mosaicism on an embryo-wide scale. To this end, we extended an approach to infer aneuploidies based on chromosome dosage-associated changes in gene expression by integrating signatures of allelic imbalance. We applied this method to published single-cell RNA sequencing data from 74 disaggregated human embryos, spanning the morula to blastocyst stages. Our analysis revealed widespread mosaic aneuploidies across preimplantation development, with 59 of 74 (80%) embryos harboring at least one aneuploid cell (1% FDR). By clustering copy number calls, we reconstructed histories of chromosome mis-segregation, distinguishing meiotic and early mitotic errors from those occurring after lineage differentiation. We observed no significant enrichment of aneuploid cells in the trophectoderm compared to the inner cell mass, though we do detect such an enrichment in published data from later post-implantation stages. Finally, we observed that aneuploid cells exhibit upregulation of immune response genes, as well as downregulation of genes involved in proliferation, metabolism, and protein processing, consistent with stress responses previously documented in other stages and systems. Together, our work provides a high-resolution view of aneuploidy in preimplantation embryos and supports the conclusion that low-level mosaicism is a common feature of early human development.

The genetics of human short stature Flores Island in Indonesia has a long history of hominin occupation, including by the extinct Homo floresiensis and a more recent settlement by modern humans. Furthermore, Flores has an extant population of pygmy humans, and H. floresiensis exhibited a diminutive adult size relative to other hominins. Tucci et al. examined genetic variation among 32 individuals, including 10 sequenced genomes, from a population of pygmies living close to the cave where H. floresiensis remains were discovered. These individuals exhibit signatures of polygenic selection explaining the short stature and have genomic content from both Neanderthals and Denisovans, but no additional archaic lineages. Thus, restricted height is under selection at this location and has evolved independently at least twice in hominins. Science , this issue p. 511

Background Fatigue occurs in 75%–95% of people with multiple sclerosis (MS) and is frequently reported as the most disabling symptom. A multicomponent group program of six weekly 2-hour sessions, Fatigue: Take Control (FTC), was developed from an international MS fatigue management guideline. Objective To determine whether FTC is associated with greater improvements in fatigue than MS: Take Control (MSTC), a similarly structured general MS education program. Methods This four-site, parallel, single-blind, randomized controlled trial compared FTC and MSTC in 204 ambulatory participants with MS. The primary outcome, the Modified Fatigue Impact Scale (MFIS), and secondary outcomes of self-efficacy, physical activity, sleep, and medications were assessed at baseline, program completion, and 3 and 6 months later. Results Mean MFIS scores improved in both groups between baseline and program completion (FTC −4.4, p < 0.001; MSTC −3.8, p < 0.001), between baseline and 3 months after program completion (FTC −3.2, p = 0.01; MSTC −3.3, p = 0.01), and between baseline and 6 months after program completion (FTC −5.2, p < 0.001; MSTC −4.8, p < 0.001). These improvements were not statistically different between groups ( p = 0.64, 0.92, and 0.82, respectively). Conclusion Participation in FTC modestly improved self-reported fatigue for up to 6 months. This improvement did not differ significantly from that occurring with the control program.

Along with errors in meiosis, mitotic errors during post-zygotic cell division contribute to pervasive aneuploidy in human embryos. Relatively little is known, however, about the genesis of these errors or their fitness consequences. Rapid technological advances are helping to close this gap, revealing diverse molecular mechanisms contributing to mitotic error. These include altered cell cycle checkpoints, aberrations of the centrosome, and failed chromatid cohesion, mirroring findings from cancer biology. Recent studies are challenging the idea that mitotic error is abnormal, emphasizing that the fitness impacts of mosaicism depend on its scope and severity. In light of these findings, technical and philosophical limitations of various screening approaches are discussed, along with avenues for future research.

This study sought to identify patient and operative demographics associated with 30-day perioperative complications in patients undergoing total ankle arthroplasty as recorded in the National Surgical Quality Improvement Project database. Complications were divided into local and systemic and further subcategorized as major and minor. A total of 404 patients underwent total ankle arthroplasty between 2007 and 2014 as captured in the National Surgical Quality Improvement Project database. The overall complication rate was 2.4% with 0.5% mortality and 0.2% infection rate. Length of hospital stay, both as an end point at >5 days and as a continuous variable, was associated with overall complications (odds ratio [OR] = 9.90, P = .002 and OR = 1.52, P = .006, respectively). Patient characteristics that predicted perioperative morbidity included presence of 3 or comorbidities (OR = 8.48, P = 0.038), American Society of Anesthesiologists class III, and history of previous cardiac surgery (OR = 12.22, P = .033). Correct patient selection is imperative in achieving improved outcomes and those that are at risk for complications should be counseled as such. Levels of Evidence: Level III: Database case control study

Objective Newborns requiring hospitalisation frequently undergo painful procedures. Prevention of pain in infants is of prime concern because of adverse associations with physiological and neurological development. However, pain mitigation is currently guided by behavioural observation assessments that have not been validated against direct evidence of pain processing in the brain. The aim of this study was to determine whether cry presence or amplitude is a valid indicator of pain processing in newborns. Design Prospective observational cohort. Setting Newborn nursery. Patients Healthy infants born at >37 weeks and Interventions We prospectively studied newborn cortical responses to light touch, cold and heel stick, and the amplitude of associated infant vocalisations using our previously published paradigms of time-locked electroencephalogram (EEG) with simultaneous audio recordings. Results Latencies of cortical peak responses to each of the three stimuli type were significantly different from each other. Of 54 infants, 13 (24%), 19 (35%) and 35 (65%) had cries in response to light touch, cold and heel stick, respectively. Cry in response to non-painful stimuli did not predict cry in response to heel stick. All infants with EEG data had measurable pain responses to heel stick, whether they cried or not. There was no association between presence or amplitude of cries and cortical nociceptive amplitudes. Conclusions In newborns with distinct brain responses to light touch, cold and pain, cry presence or amplitude characteristics do not provide adequate behavioural markers of pain signalling in the brain. New bedside assessments of newborn pain may need to be developed using brain-based methodologies as benchmarks in order to provide optimal pain mitigation.

Understanding fertility in young and old Fertility in humans follows a U-curve, with low rates in both teenagers and women of advancing maternal age (mid-30s and above). Gruhn et al. found that this distinct shape originates from chromosomal errors in human eggs, which result in genomic imbalance and pregnancy loss. The error types and chromosomes affected in the young and advanced age groups were different, suggesting that two distinct chromosome-based mechanisms balance risk associated with pregnancy and evolutionary fitness as women enter and exit their reproductive life span. The authors show that chromosome structure erodes only with advancing age, acting as a “molecular clock” for reproductive senescence. Science , this issue p. 1466

Background Mycobacterium leprae was thought to be the exclusive causative agent of leprosy until Mycobacterium lepromatosis was identified in a rare form of leprosy known as diffuse lepromatous leprosy (DLL). Methods We isolated M. lepromatosis from a patient with DLL and propagated it in athymic nude mouse footpads. Genomic analysis of this strain (NHDP-385) identified a unique repetitive element, RLPM, on which a specific real-time quantitative polymerase chain reaction assay was developed. The RLPM assay, and a previously developed RLEP quantitative polymerase chain reaction assay for M. leprae, were validated as clinical diagnostic assays according to Clinical Laboratory Improvement Amendments guidelines. We tested DNA from archived histological sections, patient specimens from the United States, Philippines, and Mexico, and US wild armadillos. Results The limit of detection for the RLEP and RLPM assays is 30 M. leprae per specimen (0.76 bacilli per reaction; coefficient of variation, 0.65%–2.44%) and 122 M. lepromatosis per specimen (3.05 bacilli per reaction; 0.84%–2.9%), respectively. In histological sections (n = 10), 1 lepromatous leprosy (LL), 1 DLL, and 3 Lucio reactions contained M. lepromatosis; 2 LL and 2 Lucio reactions contained M. leprae; and 1 LL reaction contained both species. M. lepromatosis was detected in 3 of 218 US biopsy specimens (1.38%). All Philippines specimens (n = 180) were M. lepromatosis negative and M. leprae positive. Conversely, 15 of 47 Mexican specimens (31.91%) were positive for M. lepromatosis, 19 of 47 (40.43%) were positive for M. leprae, and 2 of 47 (4.26%) contained both organisms. All armadillos were M. lepromatosis negative. Conclusions The RLPM and RLEP assays will aid healthcare providers in the clinical diagnosis and surveillance of leprosy.

The transforming growth factor beta (TGFβ) signaling pathway orchestrates a wide breadth of biological processes, ranging from bone development to reproduction. Given this, there has been a surge of interest from the drug development industry to modulate the pathway – at several points. This review discusses and provides additional context for several layers of the TGFβ signaling pathway from a structural biology viewpoint. The combination of structural techniques coupled with biophysical studies has provided a foundational knowledge of the molecular mechanisms governing this high impact, ubiquitous pathway, underlying many of the current therapeutic pursuits. This work seeks to consolidate TGFβ-related structural knowledge and educate other researchers of the apparent gaps that still prove elusive. We aim to highlight the importance of these structures and provide the contextual information to understand the contribution to the field, with the hope of advancing the discussion and exploration of the TGFβ signaling pathway. Impact statement The transforming growth factor beta (TGFβ) signaling pathway is a multifacetted and highly regulated pathway, forming the underpinnings of a large range of biological processes. Here, we review and consolidate the key steps in TGFβ signaling using literature rooted in structural and biophysical techniques, with a focus on molecular mechanisms and gaps in knowledge. From extracellular regulation to ligand–receptor interactions and intracellular activation cascades, we hope to provide an introductory base for understanding the TGFβ pathway as a whole.

Because preoperative risk factor modification is generally not possible in the emergency setting, complication prevention represents an important focus for quality improvement in emergency general surgery (EGS). The objective of our study was to determine the overall impact that specific postoperative complications have in this patient population.Our study sample consisted of patients from the 2012-2013 ACS-NSQIP database who underwent an EGS procedure. We used population attributable fractions (PAFs) to estimate the overall impact that each of 8 specific complications had on 30-day physiologic and resource use outcomes in our study population. The PAF represents the percentage reduction in a given outcome that would be anticipated if a complication were able to be completely prevented in our study population. Both unadjusted and risk-adjusted PAFs were calculated.There were 79,183 patients included for analysis. The most common complications in these patients were bleeding (6.2%), incisional surgical site infection (SSI) (3.4%), pneumonia (2.7%), and organ/space SSI (2.6%). Bleeding was the complication with the greatest overall impact on mortality and end-organ dysfunction, demonstrating an adjusted PAF of 10.7% (95% CI 8.2%,13.1%, p0.001) and 15.9% (95% CI 13.9%, 16.7%, p 0.001) for these respective outcomes. The only other complication with a sizeable impact on these outcomes was pneumonia (adjusted PAF of 7.9% for mortality and 13.2% for pneumonia). In contrast, complications such as urinary tract infection, venous thromboembolism, myocardial infarction, and incisional SSI had negligible impacts on these outcomes.Our study provides a framework for the development of high-value quality initiatives in EGS.

Contains fulltext : 208676.pdf (Publisher’s version ) (Open Access) Cleft lip with or without cleft palate (CL/P) is generally viewed as a complex trait with multiple genetic and environmental contributions. In 70% of cases, CL/P presents as an isolated feature and/or deemed nonsyndromic. In the remaining 30%, CL/P is associated with multisystem phenotypes or clinically recognizable syndromes, many with a monogenic basis. Here we report the identification, via exome sequencing, of likely pathogenic variants in two genes that encode interacting proteins previously only linked to orofacial clefting in mouse models. A variant in GDF11 (encoding growth differentiation factor 11), predicting a p.(Arg298Gln) substitution at the Furin protease cleavage site, was identified in one family that segregated with CL/P and both rib and vertebral hypersegmentation, mirroring that seen in Gdf11 knockout mice. In the second family in which CL/P was the only phenotype, a mutation in FST (encoding the GDF11 antagonist, Follistatin) was identified that is predicted to result in a p.(Cys56Tyr) substitution in the region that binds GDF11. Functional assays demonstrated a significant impact of the specific mutated amino acids on FST and GDF11 function and, together with embryonic expression data, provide strong evidence for the importance of GDF11 and Follistatin in the regulation of human orofacial development.

STUDY QUESTION\ud Is a clinical trophectoderm (TE) biopsy a suitable predictor of chromosomal aneuploidy in blastocysts?\ud \ud SUMMARY ANSWER\ud In the analyzed group of blastocysts, a clinical TE biopsy was an excellent representative of blastocyst karyotype in cases of whole chromosome aneuploidy, but in cases of only segmental (sub-chromosomal) aneuploidy, a TE biopsy was a poor representative of blastocyst karyotype.\ud \ud WHAT IS KNOWN ALREADY\ud Due to the phenomenon of chromosomal mosaicism, concern has been expressed about the possibility of discarding blastocysts classified as aneuploid by preimplantation genetic testing for aneuploidy (PGT-A) that in fact contain a euploid inner cell mass (ICM). Previously published studies investigating karyotype concordance between TE and ICM have examined small sample sizes and/or have utilized chromosomal analysis technologies superseded by Next Generation Sequencing (NGS). It is also known that blastocysts classified as mosaic by PGT-A can result in healthy births. TE re-biopsy of embryos classified as aneuploid can potentially uncover new instances of mosaicism, but the frequency of such blastocysts is currently unknown.\ud \ud STUDY DESIGN, SIZE, DURATION\ud For this study, 45 patients donated 100 blastocysts classified as uniform aneuploids (non-mosaic) using PGT-A by NGS (n = 93 whole chromosome aneuploids, n = 7 segmental aneuploids). In addition to the original clinical TE biopsy used for PGT-A, each blastocyst was subjected to an ICM biopsy as well as a second TE biopsy. All biopsies were processed for chromosomal analysis by NGS, and karyotypes were compared to the original TE biopsy.\ud \ud PARTICIPANTS/MATERIALS, SETTING, METHODS\ud The setting for this study was a single IVF center with an in-house PGT-A program and associated research laboratory.\ud \ud MAIN RESULTS AND THE ROLE OF CHANCE\ud When one or more whole chromosomes were aneuploid in the clinical TE biopsy, the corresponding ICM was aneuploid in 90 out of 93 blastocysts (96.8%). When the clinical TE biopsy contained only segmental (sub-chromosomal) aneuploidies, the ICM was aneuploid in three out of seven cases (42.9%). Blastocysts showing aneuploidy concordance between clinical TE biopsy and ICM were also aneuploid in a second TE biopsy in 86 out of 88 cases (97.7%). In blastocysts displaying clinical TE–ICM discordance, a second TE biopsy was aneuploid in only two out of six cases (33.3%).\ud \ud LIMITATIONS, REASONS FOR CAUTION\ud All embryos in this study had an initial classification of ‘aneuploid’ and not ‘euploid’ or ‘mosaic’. Therefore, the findings of this study refer specifically to a TE biopsy predicting aneuploidy in the remaining blastocyst, and cannot be extrapolated to deduce the ability of a TE biopsy to predict euploidy in the blastocyst. No conclusions should be drawn from this study about the ability of a mosaic TE biopsy to predict the karyotype of the corresponding blastocyst. Caution should be exercised in generalizing the findings of the sample group of this study to the general IVF blastocyst population. The segmental aneuploidy group only contained seven samples.\ud \ud WIDER IMPLICATIONS OF THE FINDINGS\ud The high rate of intra-blastocyst concordance observed in this study concerning whole chromosome aneuploidy contributes experimental evidence to the validation of PGT-A at the blastocyst stage. Concomitantly, the results suggest potential clinical value in reassessing blastocysts deemed aneuploid by TE re-biopsy in select cases, particularly in instances of segmental aneuploidies. This could impact infertility treatment for patients who only have blastocysts classified as aneuploid by PGT-A available.\ud \ud STUDY FUNDING/COMPETING INTEREST(S)\ud This study was supported by the Zouves Foundation for Reproductive Medicine and Zouves Fertility Center. The authors have no competing interest to disclose.

Objectives To assess the association of the Pharmacists' Pneumonia Prevention Program (PPPP) with changes in beliefs related to pneumonia vaccination (PV) in a predominately older African American population. Methods PPPP was an educational intervention delivered using a senior center model of care consisting of a formal pharmacist presentation, live skit, small group action planning, and optional PV. A 15-item instrument assessed participants' beliefs at baseline, post-test, and three months across four domains: pharmacists and pharmacies, vaccination, pneumococcal disease, and physicians. Friedman tests and pairwise Wilcoxon signed rank tests were used to determine the statistical significance of the mean change in belief responses across timepoints. Results 190 older adults participated; the sample was majority female (76.3%) and African American (80.5%), and had a mean age of 74.3 years. Statistically significant improvements in beliefs at post-test were observed in the following domains: pharmacists and pharmacies, vaccination, and the pneumococcal disease; however, some of these gains were incompletely sustained at three months. Conclusion PPPP positively impacted beliefs post-program regarding the pneumococcal disease, pharmacists and pharmacies, and vaccination; however, sustained efforts may be needed to reinforce these gains. Policy implications Support for pharmacist educational services in senior centers should be considered.

Objective\ud To investigate the parameters of mosaicism and the biological mechanisms leading to healthy pregnancies from mosaic embryo transfers.\ud \ud Design\ud Prospective study.\ud \ud Setting\ud IVF center and associated research laboratory.\ud \ud Patient(s)\ud Fifty-nine patients.\ud \ud Intervention(s)\ud Embryos underwent blastocyst-stage preimplantation genetic testing for aneuploidy by next-generation sequencing. Trophectoderm biopsies containing 20%–80% abnormal cells were deemed mosaic, and corresponding blastocysts were transferred. Mosaic embryos donated to research were examined for karyotype concordance in multiple biopsies and assessed for cell proliferation and death by immunofluorescence and computational quantitation.\ud \ud Main Outcome Measure(s)\ud Chemical start of pregnancy, implantation, fetal heartbeat, and birth.\ud \ud Result(s)\ud Globally, mosaic embryos showed inferior clinical outcomes compared with euploid embryos. Aneuploid cell percentage in trophectoderm biopsies did not correlate with outcomes, but type of mosaicism did, as embryos with single mosaic segmental aneuploidies fared better than all other types. Mosaic blastocysts generated from oocytes retrieved at young maternal ages (?34 years) showed better outcomes than those retrieved at older maternal ages. Mosaic embryos displayed low rates of karyotype concordance between multiple biopsies and showed significant elevation of cell proliferation and death compared with euploid embryos.\ud \ud Conclusion(s)\ud After euploid embryos, mosaic embryos can be considered for transfer, prioritizing those of the single segmental mosaic type. If a patient has mosaic embryos available that were generated at different ages, preference should be given to those made at younger ages. Intrablastocyst karyotype discordance and differential cell proliferation and death might be reasons that embryos classified as mosaic can result in healthy pregnancies and babies.

Limited evidence describes promoting development and reducing violence in low- and middle-income countries (LMICs), a missed opportunity to protect children and promote development and human capital. This study presents a systematic literature review of integrated early childhood development plus violence prevention (ECD+VP) interventions in LMICs. The search yielded 5,244 unique records, of which N = 6 studies met inclusion criteria. Interventions were in Chile, Jamaica, Lebanon, Mexico, Mozambique, and Turkey. Five interventions were parent education programs, including center-based sessions (n = 3) and home visiting (n = 2), while one intervention was a teacher education program. All but one study reported improvements in both child development and maltreatment outcomes. The dearth of evidence on ECD+VP interventions suggests additional research is needed. Integrated ECD+VP interventions may improve multiple child outcome domains while leveraging limited resources in LMICs.

Myostatin, a key regulator of muscle mass in vertebrates, is biosynthesised as a latent precursor in muscle and is activated by sequential proteolysis of the pro-domain. To investigate the molecular mechanism by which pro-myostatin remains latent, we have determined the structure of unprocessed pro-myostatin and analysed the properties of the protein in its different forms. Crystal structures and SAXS analyses show that pro-myostatin adopts an open, V-shaped structure with a domain-swapped arrangement. The pro-mature complex, after cleavage of the furin site, has significantly reduced activity compared with the mature growth factor and persists as a stable complex that is resistant to the natural antagonist follistatin. The latency appears to be conferred by a number of distinct features that collectively stabilise the interaction of the pro-domains with the mature growth factor, enabling a regulated stepwise activation process, distinct from the prototypical pro-TGF-β1. These results provide a basis for understanding the effect of missense mutations in pro-myostatin and pave the way for the design of novel myostatin inhibitors.

Growth/differentiation factor 8 (GDF8), or myostatin, negatively regulates muscle mass. GDF8 is held in a latent state through interactions with its N-terminal prodomain, much like TGF-β. Using a combination of small-angle X-ray scattering and mutagenesis, we characterized the interactions of GDF8 with its prodomain. Our results show that the prodomain:GDF8 complex can exist in a fully latent state and an activated or "triggered" state where the prodomain remains in complex with the mature domain. However, these states are not reversible, indicating the latent GDF8 is "spring-loaded." Structural analysis shows that the prodomain:GDF8 complex adopts an "open" configuration, distinct from the latency state of TGF-β and more similar to the open state of Activin A and BMP9 (nonlatent complexes). We determined that GDF8 maintains similar features for latency, including the alpha-1 helix and fastener elements, and identified a series of mutations in the prodomain of GDF8 that alleviate latency, including I56E, which does not require activation by the protease Tolloid. In vivo, active GDF8 variants were potent negative regulators of muscle mass, compared with WT GDF8. Collectively, these results help characterize the latency and activation mechanisms of GDF8.

PURPOSE OF THE STUDY To facilitate replication, we examined delivery characteristics, acceptability, and depression outcomes of a home-based intervention, Get Busy Get Better, Helping Older Adults Beat the Blues (GBGB). GBGB, previously tested in a randomized trial, reduced depressive symptoms and enhanced quality of life in African Americans. DESIGN AND METHODS A total of 208 African Americans aged above 55 years with Patient Health Questionnaire (PHQ-9) scores ≥5 on two subsequent screenings were randomized to receive GBGB immediately or 4 months later. GBGB involves up to 10 home sessions consisting of care management, referral/linkage, depression education/symptom recognition, stress reduction, and behavioral activation. Interventionists recorded delivery characteristics (dose, intensity) and perceived acceptability of sessions. Baseline and post-tests were used to characterize participants and examine associations between dose/intensity and depression scores. Participant satisfaction and perceived benefits were examined at 8 months. RESULTS Of 208 participants, 181 (87%, mean age = 69.6) had treatment data. Of these, 165 (91.2%) had ≥3 treatment sessions (minimal dose). Participants had on average 8.1 sessions (SD = 2.6) for an average of 65.4min (SD = 18.3) each. Behavioral activation and care management were provided the most (average of six sessions for average duration = 17.9 and 22.2min per session respectively), although all participants received each treatment component. GBGB was perceived as highly acceptable and beneficial by interventionists and participants. More sessions and time in program were associated with greater symptom reduction. IMPLICATIONS GBGB treatment components were highly acceptable to participants. Future implementation and sustainability challenges include staffing, training requirements, reimbursement limitations, competing agency programmatic priorities, and generalizability to other groups.

Background: Vaccination is the best way to prevent pneumococcal disease (PD), but 40% of older adults remain unvaccinated nationwide, with even greater nonvaccination rates among African Americans (AAs). Prior studies suggest that insufficient knowledge contributes to low vaccination rates. The Pharmacists’ Pneumonia Prevention Program (PPPP) was designed to improve older adults’ knowledge about PD and pneumococcal vaccination (PV). Objective: To measure PPPP’s effect on knowledge and activation in a predominantly AA population and determine program costs. Methods: PPPP uses a senior center model with a pharmacist presentation, actors’ skit, and small-group action planning. Knowledge about PD risk, transmission, symptoms, and PV side effects was assessed at baseline (BL), postintervention (PT), and 3 months (M3) and analyzed using an intention-to-treat (ITT) approach. Actions taken (got vaccinated, spoke to doctor or pharmacist, discussed with family/friends) were assessed at M3. PPPP costs ($US 2013) included staff time, PV, actor, and site fees. Results: Of 276 attending PPPP, 190 consented and were included in the ITT sample, which was largely black (80.5%) and female (76.3%) and had a mean age of 74.4 years. Knowledge improved by 46.8% (BL vs PT), with significant gains in all domains. At M3, knowledge improved by 54.2% vs BL, indicating sustained gains; 37.2% of previously unvaccinated participants reported receiving PV by M3. Program cost was $119 per attendee. Conclusion: PPPP significantly improved PD and PV knowledge. It could be delivered more efficiently by holding larger events on fewer dates, staffing with volunteers where appropriate, and utilizing a local pharmacy to manage the vaccine supply.

Using a powerful machine learning approach, a recent study of human genomes has revealed widespread footprints of recent positive selection on standing genetic variation.

PURPOSE: This study aimed to determine if patients with infertility or recurrent pregnancy loss have higher rates of embryo aneuploidy than fertile controls. METHODS: This was a retrospective review of all pre-implantation genetic screening (PGS) cases processed by a single reference lab prior to March 2014 after a blastocyst biopsy. Cases were excluded if no indication for PGS was designated or patients were translocation carriers. The fertile control group consisted of patients undergoing IVF with PGS for sex selection only. The comparison cohorts included those with recurrent pregnancy loss, male factor infertility, unexplained infertility, prior failed IVF, or previous aneuploid conceptions. A quasi-binomial regression model was used to assess the relationship between the dependent variable, aneuploidy rate and the independent variables, maternal age and reason for PGS. A quasi-Poisson regression model was used to evaluate the relationship between similar independent variables and the number of blastocyst biopsies per case. RESULTS: The initial study population consisted of 3378 IVF-PGS cycles and 18,387 analyzed trophectoderm samples. Controlling for maternal age, we observed an increased rate of aneuploidy among patients with recurrent pregnancy loss (OR 1.330, p 0.05). The increase in aneuploidy in patients with RPL and prior IVF failure was driven by both an increase in meiotic (OR 1.488 and 1.508, p

Assisted reproductive technologies (ART) have become the standard of care for the treatment of infertility. Within this realm, reliable prediction of the developmental potential of the pre‐implantation human embryo remains an overriding priority. One such technology, pre‐implantation genetic screening (PGS), is being increasingly deployed to select against embryonic aneuploidy [1]. However, a growing number of seemingly contradictory outcome reports are forcing a reevaluation of this approach. Here, we discuss how biological factors, notably mitotic aneuploidy during early embryonic development, limit the very rationale for PGS as a clinical diagnostic method. > … PGS is an example of technology compromised by biology The development of safe and efficient methods to select healthy euploid embryos constitutes a pressing need to improve the success of ART. PGS, as one strategy to achieve this, relies on the ploidy status of the trophectoderm layer of the blastocyst‐stage embryo [1] (Table 1). Considerable numbers of patients are undergoing PGS: In the USA alone, more than 5% of 106,902 non‐donor assisted reproduction cycles resorted to PGS during 2011 and 2012 [2]. However, the capacity of PGS to select euploid embryos has recently been questioned by the birth of healthy newborns whose originating blastocysts were deemed mosaic (euploid–aneuploid) [3]. Similar inconsistencies have previously been reported for euploid human embryonic stem cell lines, which have been derived from purportedly aneuploid blastocysts. We suggest herein that the utility of PGS is undermined by innate karyotypic mosaicism, the ontogeny and significance of which in early human development remain uncertain. Viewed in this light, PGS is an example of technology compromised by biology. It follows that the ability of PGS to reliably predict the ploidy status of the human embryo and its developmental potential is limited. View this table: Table 1. Blastocyst developmental potential as inferred from the PGS biopsy ploidy status ### The causes of embryonic aneuploidy Following fertilization and karyogamy, the human zygote undergoes 8–9 …

Regulatory variation influencing gene expression is a key contributor to phenotypic diversity, both within and between species. Unfortunately, RNA degrades too rapidly to be recovered from fossil remains, limiting functional genomic insights about our extinct hominin relatives. Many Neanderthal sequences survive in modern humans due to ancient hybridization, providing an opportunity to assess their contributions to transcriptional variation and to test hypotheses about regulatory evolution. We developed a flexible Bayesian statistical approach to quantify allele-specific expression (ASE) in complex RNA-seq datasets. We identified widespread expression differences between Neanderthal and modern human alleles, indicating pervasive cis-regulatory impacts of introgression. Brain regions and testes exhibited significant downregulation of Neanderthal alleles relative to other tissues, consistent with natural selection influencing the tissue-specific regulatory landscape. Our study demonstrates that Neanderthal-inherited sequences are not silent remnants of ancient interbreeding but have measurable impacts on gene expression that contribute to variation in modern human phenotypes.

Since the introduction of laparoscopic surgery for cholecystectomy in 1989, the growth of minimally invasive surgery (MIS) has increased significantly in the United States. There is a growing concern that the pendulum has now shifted too far toward MIS and that current general surgery residents' exposure to open abdominal procedures is lacking.We sought to analyze trends in open vs MIS intra-abdominal procedures performed by residents graduating from US general surgery residency programs over the past twelve years.We conducted a retrospective analysis of the data from the ACGME national resident case log reports for graduating US general surgery residents from 2000 to 2011. We analyzed the average number of cases per graduating chief resident for the following surgical procedures: appendectomy, inguinal/femoral hernia repair, gastrostomy, colectomy, antireflux procedures, and cholecystectomy.For all the procedures analyzed, except antireflux procedures, a statistically significant increase in the number of MIS cases was seen. The increases in MIS procedures were as follows: appendectomy, 8.5 to 46 (542%); inguinal/femoral hernia repair, 7.6 to 23.3 (265%); gastrostomy, 1.4 to 3 (114%); colectomy, 1.8 to 18.2 (1011%); and cholecystectomy, 84 to 105.7 (26%). The p value was set at0.001 for all procedures. There has been a concomitant decrease in the number of open procedures. The numbers of open appendectomy decreased from 30.9 to 15.5 (p0.0001), open inguinal/femoral hernia repair from 52.1 to 48 (p = 0.0038), open gastrostomy from 7.7 to 4.9 (p = 0.0094), open colectomy from 48 to 40.7 (p0.0001), open cholecystectomy from 15.5 to 10.4 (p = 0.0005), and open antireflux procedures from 4.7 to 1.7 (p0.001). An analysis conducted over time reveals that the rates of increase in MIS procedures in 5 of the 6 categories continue to rise, whereas the rates of open appendectomy, open colectomy, and open antireflux procedures continue to decrease. However, the rates of decline of open hernia repairs and open gastrostomies seem to have plateaued.The performance of open procedures in general surgery residency has declined significantly in the past 12 years. The effect of the decline in open cases in surgical training and practice remains to be determined.

Oral administration of the amino acid/inhibitory neurotransmitter gamma aminobutyric acid (GABA) reportedly elevates resting serum growth hormone (GH) concentrations.To test the hypothesis that GABA ingestion stimulates immunoreactive GH (irGH) and immunofunctional GH (ifGH) release at rest and that GABA augments the resistance exercise-induced irGH/ifGH responses.Eleven resistance-trained men (18-30 yr) participated in this randomized, double-blind, placebo-controlled, crossover study. During each experimental bout, participants ingested either 3 g of GABA or sucrose placebo (P), followed either by resting or resistance exercise sessions. Fasting venous blood samples were acquired immediately before and at 15, 30, 45, 60, 75, and 90 min after GABA or P ingestion and were assayed for irGH and ifGH.At rest, GABA ingestion elevated both irGH and ifGH compared with placebo. Specifically, peak concentrations of both hormones were elevated by about 400%, and the area under the curve (AUC) was elevated by about 375% (P0.05). Resistance exercise (EX-P) elevated time-point (15-60 min) irGH and ifGH concentrations compared with rest (P0.05). The combination of GABA and resistance exercise (EX-GABA) also elevated the peak, AUC, and the 15- to 60-min time-point irGH and ifGH responses compared with resting conditions (P0.05). Additionally, 200% greater irGH (P0.01) and 175% greater ifGH (P0.05) concentrations were observed in the EX-GABA than in the EX-P condition, 30 min after ingestion. GABA ingestion did not alter the irGH to ifGH ratio, and, under all conditions, ifGH represented approximately 50% of irGH.Our data indicate that ingested GABA elevates resting and postexercise irGH and ifGH concentrations. The extent to which irGH/ifGH secretion contributes to skeletal muscle hypertrophy is unknown, although augmenting the postexercise irGH/ifGH response may improve resistance training-induced muscular adaptations.

Objectives: Report results of a randomized-clinical trial of the efficacy of periodontal care in the improvement of glycemic control in 165 veterans with poorly controlled diabetes over 4 months. Methods: Outcomes were change in Haemoglobin A1c (HbAlc) in the Early Treatment versus untreated (Usual Care) groups and percent of participants with decreases in HbAlc. Analyses included simple/multiple variable linear/logistic regressions, adjusted for baseline HbAlc, age, and duration of diabetes. Results: Unadjusted analyses showed no differences between groups. After adjustment for baseline HbAlc, age, and diabetes duration, the mean absolute HbAlc change in the Early Treatment group was - 0.65% versus - 0.51% in the Usual Care group (p = 0.47). Adjusted odds for improvement by 0.5% in the Early Treatment group was 1.67 (95% confidence interval: 0.84, 3.34, p = 0.14). Usual Care subjects were twice as likely to increase insulin from baseline to 4 months (20% versus 11%, p = 0.12) and less likely to decrease insulin (1% versus 6%, p = 0.21) than Early Treatment subjects. Among insulin users at baseline, more increased insulin in the Usual Care group (40% versus 21%, p = 0.06). Conclusions: No significant benefit was found for periodontal therapy after 4 months in this study; trends in some results were in favour of periodontal treatment.

Denisovan DNA retained in Melanesians Modern humans carry remnants of DNA from interbreeding events with archaic lineages, such as Neandertals. However, people from Oceania also retain genes from a second ancient lineage, the Denisovans. Vernot et al. surveyed archaic genomic sequences in a worldwide sample of modern humans, including 35 individuals from the Melanesian Islands. All non-African genomes surveyed contained Neandertal DNA, but a significant Denisovan component was found only in the Melanesians. Reconstruction of this genetic history suggests that Neandertals bred with modern humans multiple times, but Denosivans only once, in ancestors of modern-day Melanesians. Science , this issue p. 235

Objective To determine the effect of maternal age on the average number of euploid embryos retrieved during oocyte harvest as part of an in vitro fertilization (IVF) cycle, including the probability of retrieving at least one euploid embryo in a cohort (PrE). Design Retrospective study. Setting Preimplantation genetic screening (PGS) laboratory. Patient(s) Women aged 18 to 48 years undergoing IVF treatment. Intervention(s) Use of 24-chromosome single-nucleotide polymorphism (SNP)-based PGS of day-3 and day-5 embryo biopsies. Main Outcome Measure(s) Relationships between maternal age and the rate of embryos that tested as euploid (hereafter referred to as "euploid embryos"), the average number and proportion of euploid embryos per IVF cycle, and PrE. Result(s) We analyzed 22,599 day-3 embryos and 15,112 day-5 embryos. In women aged 27 to 35 years, the median proportion of euploid embryos in each cycle remained constant at ∼35% in day-3 biopsies and ∼55% in day-5 biopsies, but it decreased rapidly after age 35. On average, women in their late 20s had four euploid embryos (day 3 or day 5) per cycle, but this number decreased linearly (R 2 ≥ 0.983) after 35 years of age. The effect of maternal age on PrE was similar, with a rapid exponential decline (R 2 = 0.986). Across all maternal ages, the euploid proportion and number of embryos per cycle were counterbalanced, so the number of euploid embryos per cycle was the same for day-3 and day-5 biopsies. This suggests that the loss of embryos from day 3 to day 5 was primarily due to aneuploidy. Conclusion(s) Our results confirm the known inverse relationship between advanced maternal age (>35 years) and embryo euploidy, demonstrating that equal numbers of euploid embryos are available at day 3 and day 5.

Whole-chromosome imbalances affect over half of early human embryos and are the leading cause of pregnancy loss. While these errors frequently arise in oocyte meiosis, many such whole-chromosome abnormalities affecting cleavage-stage embryos are the result of chromosome missegregation occurring during the initial mitotic cell divisions. The first wave of zygotic genome activation at the 4–8 cell stage results in the arrest of a large proportion of embryos, the vast majority of which contain whole-chromosome abnormalities. Thus, the full spectrum of meiotic and mitotic errors can only be detected by sampling after the initial cell divisions, but prior to this selective filter. Here, we apply 24-chromosome preimplantation genetic screening (PGS) to 28,052 single-cell day-3 blastomere biopsies and 18,387 multi-cell day-5 trophectoderm biopsies from 6,366 in vitro fertilization (IVF) cycles. We precisely characterize the rates and patterns of whole-chromosome abnormalities at each developmental stage and distinguish errors of meiotic and mitotic origin without embryo disaggregation, based on informative chromosomal signatures. We show that mitotic errors frequently involve multiple chromosome losses that are not biased toward maternal or paternal homologs. This outcome is characteristic of spindle abnormalities and chaotic cell division detected in previous studies. In contrast to meiotic errors, our data also show that mitotic errors are not significantly associated with maternal age. PGS patients referred due to previous IVF failure had elevated rates of mitotic error, while patients referred due to recurrent pregnancy loss had elevated rates of meiotic error, controlling for maternal age. These results support the conclusion that mitotic error is the predominant mechanism contributing to pregnancy losses occurring prior to blastocyst formation. This high-resolution view of the full spectrum of whole-chromosome abnormalities affecting early embryos provides insight into the cytogenetic mechanisms underlying their formation and the consequences for human fertility., Author Summary By day 3 of development, more than half of human embryos contain at least one cell that deviates from the typical 46-chromosome complement. These whole-chromosome abnormalities include polyploidies, which affect the entire chromosome set, as well as aneuploidies, which involve gains and losses of particular chromosomes. The rate of aneuploidy increases with maternal age, primarily due to chromosome segregation errors arising during egg formation (maternal meiosis). While some forms of aneuploidy, such as Trisomy 21, are compatible with live birth, most aneuploid embryos do not survive to term. Our study applied genetic techniques to screen early embryos from in vitro fertilization cycles, demonstrating that while diverse whole-chromosome abnormalities can be observed at early developmental stages, these errors are strongly filtered during preimplantation development. Specifically, errors occurring during the initial post-fertilization cell divisions often result in the simultaneous loss of multiple chromosomes, a pattern consistent with abnormal cell division. Our data provide evidence of selection against this class of aneuploidy before day 5 of development, thus reducing fertility. Patients referred for genetic screening due to previous IVF failure had higher rates of mitotic error, highlighting its clinical relevance and indicating that patient-specific genetic and environmental factors influence error rates.

Chromosome number varies in humans Pregnancy loss is often associated with a loss of chromosome number, a condition known as aneuploidy. When examining aneuploid embryos during in vitro fertilization cycles, McCoy et al. found a large genomic region associated with defects in maternal chromosome number (see the Perspective by Vohr and Green). This region contains a gene, Polo-like Kinase 4 ( PLK4 ), that is known to affect chromosome segregation and has variants that correlate with an increased rate of maternal aneuploidy. Surprisingly, such variants occur at relatively high levels in human populations and may be under positive selection. Science , this issue p. 235 ; see also p. 180

Since the development of a dependable and durable synthetic non-autogenous vascular conduit in the mid-twentieth century, the field of vascular surgery has experienced tremendous growth. Concomitant with this growth, development in the field of bioengineering and the development of different tissue engineering techniques have expanded the armamentarium of the surgeon for treating a variety of complex cardiovascular diseases. The recent development of completely tissue engineered vascular conduits that can be implanted for clinical application is a particularly exciting development in this field. With the rapid advances in the field of tissue engineering, the great hope of the surgeon remains that this conduit will function like a true blood vessel with an intact endothelial layer, with the ability to respond to endogenous vasoactive compounds. Eventually, these engineered tissues may have the potential to supplant older organic but not truly biologic technologies, which are used currently.