Infants born with esophageal atresia and tracheoesophageal fistula, a complex congenital malformation occurring in 1/2500–4000 live births, may suffer threats to their cardiac, respiratory, and ...digestive health in addition to anomalies that may exist in the genitourinary and musculoskeletal systems. Optimal care for these patients throughout their lives is best achieved through a coordinated, multidisciplinary approach that our health care system is not always well‐equipped to provide. This review, though not exhaustive, highlights the components of care that pertain to initial surgical reconstruction and subsequent diagnosis and management of the complications that are most frequently encountered. Authors from among the many specialties involved in the care of these patients summarize the current best practice with attention to the most recent advances. Assessment and improvement of quality of life and transition to adult specialists as children grow to adulthood is also reviewed.
The DNA methyltransferase component of the type I restriction and modification enzyme of Escherichia coli K12 has been purified.
The active component, a trimer of molecular mass 170 kDa consisting of ...one DNA recognition subunit (S) and two modification
subunits (M), showed the expected preference for modifying a hemimethylated substrate rather than an unmethylated one. Small
amounts of the dimers M2 and M1S1 were also isolated. Subunit rearrangements of the three protein species occurred on ion
exchange and heparin-agarose chromatography. Denaturation of the trimer gave folding intermediates, and these and the dimer
forms isolated during purification may reflect the assembly of the protein in vivo. Enzyme activity was recovered on refolding
the denatured protein by dilution of the denaturant. A comparison of the predicted isoelectric points of all known S subunits
of type I restriction and modification enzymes revealed values that correlated with the arrangement of type I systems in several
families. Electrostatic interactions may explain the different subunit stoichiometries observed during purification of type
I enzymes and the differing preferences for hemimethylated DNA displayed by the three type I families.
For type I restriction systems, recently determined nucleotide sequences predict conserved amino acids in the subunit that is essential for restriction but not modification (HsdR). The conserved ...sequences emphasize motifs characteristic of the DEAD-box family of proteins which comprises putative helicases, and they identify a new candidate for motif IV. We provide evidence based on an analysis of EcoKI which supports both the relevance of DEAD-box motifs to the mechanism of restriction and the new definition of motif IV. Amino acid substitutions within the newly identified motif IV and those in six other previously identified DEAD-box motifs, but not in the original motif IV, confer restriction-deficient phenotypes. We have examined the relevance of the DEAD-box motifs to the restriction pathway by determining the steps permitted in vitro by the defective enzymes resulting from amino acid substitutions in each of the seven motifs. EcoKI purified from the seven restriction-deficient mutants binds to an unmethylated target sequence and, in the presence of AdoMet, responds to ATP by undergoing the conformational change essential for the pathway of events leading to DNA cleavage. The seven enzymes have little or no ATPase activity and no endonuclease activity, but they retain the ability to nick unmodified DNA, though at reduced rates. Nicking of a DNA strand could therefore be an essential early step in the restriction pathway, facilitating the ATP-dependent translocation of DNA, particularly if this involves DNA helicase activity.
Directed acyclic graphs (DAGs) are an increasingly popular approach for identifying confounding variables that require conditioning when estimating causal effects. This review examined the use of ...DAGs in applied health research to inform recommendations for improving their transparency and utility in future research.
Original health research articles published during 1999-2017 mentioning 'directed acyclic graphs' (or similar) or citing DAGitty were identified from Scopus, Web of Science, Medline and Embase. Data were extracted on the reporting of: estimands, DAGs and adjustment sets, alongside the characteristics of each article's largest DAG.
A total of 234 articles were identified that reported using DAGs. A fifth (n = 48, 21%) reported their target estimand(s) and half (n = 115, 48%) reported the adjustment set(s) implied by their DAG(s). Two-thirds of the articles (n = 144, 62%) made at least one DAG available. DAGs varied in size but averaged 12 nodes interquartile range (IQR): 9-16, range: 3-28 and 29 arcs (IQR: 19-42, range: 3-99). The median saturation (i.e. percentage of total possible arcs) was 46% (IQR: 31-67, range: 12-100). 37% (n = 53) of the DAGs included unobserved variables, 17% (n = 25) included 'super-nodes' (i.e. nodes containing more than one variable) and 34% (n = 49) were visually arranged so that the constituent arcs flowed in the same direction (e.g. top-to-bottom).
There is substantial variation in the use and reporting of DAGs in applied health research. Although this partly reflects their flexibility, it also highlights some potential areas for improvement. This review hence offers several recommendations to improve the reporting and use of DAGs in future research.
The transcription factors OCT4, SOX2, and NANOG have essential roles in early development and are required for the propagation of undifferentiated embryonic stem (ES) cells in culture. To gain ...insights into transcriptional regulation of human ES cells, we have identified OCT4, SOX2, and NANOG target genes using genome-scale location analysis. We found, surprisingly, that OCT4, SOX2, and NANOG co-occupy a substantial portion of their target genes. These target genes frequently encode transcription factors, many of which are developmentally important homeodomain proteins. Our data also indicate that OCT4, SOX2, and NANOG collaborate to form regulatory circuitry consisting of autoregulatory and feedforward loops. These results provide new insights into the transcriptional regulation of stem cells and reveal how OCT4, SOX2, and NANOG contribute to pluripotency and self-renewal.
Over the past few decades, social and economic changes have had substantial effects on health and wellbeing in Russia. We aimed to use data from the Global Burden of Diseases, Injuries, and Risk ...Factors Study 2016 (GBD 2016) to evaluate trends in mortality, causes of death, years lived with disability (YLDs), years of life lost (YLLs), disability-adjusted life-years (DALYs), and associated risk factors in Russia from 1980 to 2016.
We estimated all-cause mortality by use of a multistage modelling process that synthesised data from vital registration systems, surveys, and censuses. A composite measure of health loss due to both fatal and non-fatal disease burden (DALYs) was calculated as the sum of YLLs and YLDs for each age, sex, year, and location. Health progress was evaluated in comparison with patterns of change in similar countries by use of the Socio-demographic Index that was developed for GBD 2016.
Following rapid decreases in life expectancy after the collapse of the Soviet Union, life expectancy at birth in Russia improved between 2006 and 2016. The all-cause mortality rate decreased by 16·6% (95% uncertainty interval 9·4–33·8) between 1980 and 2016. This overall decrease encompasses the cycles of sharp increases and plateaus in mortality that occurred before 2005. Child mortality decreased by 57·5% (53·5–61·1) between 2000 and 2016. However, compared with countries at similar Socio-demographic Index levels, rates of mortality and disability in Russia remain high and life expectancy is low. Russian men have a disproportionate burden of disease relative to women. In 2016, 59·2% (55·3–62·6) of mortality in men aged 15–49 years and 46·8% (44·5–49·5) of mortality in women were attributable to behavioural risk factors, including alcohol use, drug use, and smoking.
Trends in mortality in Russia from 1980 to 2016 might be related to complicated patterns of behavioural risk factors associated with economic and social change, to shifts in disease burden, and to changes in the capacity of and access to health care. Ongoing mortality and disability from causes and risks amenable to health-care interventions and behaviour modifications present opportunities to continue to improve the wellbeing of Russian citizens.
Bill & Melinda Gates Foundation.
Human movement researchers are often restricted to laboratory environments and data capture techniques that are time and/or resource intensive. Markerless pose estimation algorithms show great ...potential to facilitate large scale movement studies 'in the wild', i.e., outside of the constraints imposed by marker-based motion capture. However, the accuracy of such algorithms has not yet been fully evaluated. We computed 3D joint centre locations using several pre-trained deep-learning based pose estimation methods (OpenPose, AlphaPose, DeepLabCut) and compared to marker-based motion capture. Participants performed walking, running and jumping activities while marker-based motion capture data and multi-camera high speed images (200 Hz) were captured. The pose estimation algorithms were applied to 2D image data and 3D joint centre locations were reconstructed. Pose estimation derived joint centres demonstrated systematic differences at the hip and knee (~ 30-50 mm), most likely due to mislabeling of ground truth data in the training datasets. Where systematic differences were lower, e.g., the ankle, differences of 1-15 mm were observed depending on the activity. Markerless motion capture represents a highly promising emerging technology that could free movement scientists from laboratory environments but 3D joint centre locations are not yet consistently comparable to marker-based motion capture.
Polycomb group proteins are essential for early development in metazoans, but their contributions to human development are not well understood. We have mapped the Polycomb Repressive Complex 2 (PRC2) ...subunit SUZ12 across the entire nonrepeat portion of the genome in human embryonic stem (ES) cells. We found that SUZ12 is distributed across large portions of over two hundred genes encoding key developmental regulators. These genes are occupied by nucleosomes trimethylated at histone H3K27, are transcriptionally repressed, and contain some of the most highly conserved noncoding elements in the genome. We found that PRC2 target genes are preferentially activated during ES cell differentiation and that the ES cell regulators OCT4, SOX2, and NANOG cooccupy a significant subset of these genes. These results indicate that PRC2 occupies a special set of developmental genes in ES cells that must be repressed to maintain pluripotency and that are poised for activation during ES cell differentiation.
The ability to accurately and non-invasively measure 3D mass centre positions and their derivatives can provide rich insight into the physical demands of sports training and competition. This study ...examines a method for non-invasively measuring mass centre velocities using markerless human pose estimation and Kalman smoothing. Marker (Qualysis) and markerless (OpenPose) motion capture data were captured synchronously for sprinting and skeleton push starts. Mass centre positions and velocities derived from raw markerless pose estimation data contained large errors for both sprinting and skeleton pushing (mean ± SD = 0.127 ± 0.943 and -0.197 ± 1.549 m·s
, respectively). Signal processing methods such as Kalman smoothing substantially reduced the mean error (±SD) in horizontal mass centre velocities (0.041 ± 0.257 m·s
) during sprinting but the precision remained poor. Applying pose estimation to activities which exhibit unusual body poses (e.g., skeleton pushing) appears to elicit more erroneous results due to poor performance of the pose estimation algorithm. Researchers and practitioners should apply these methods with caution to activities beyond sprinting as pose estimation algorithms may not generalise well to the activity of interest. Retraining the model using activity specific data to produce more specialised networks is therefore recommended.
Platelet von Willebrand factor (vWf) is located in the alpha granules. Individuals with type I von Willebrand's disease (vWd) with prolonged bleeding times are best discriminated from those who have ...normal bleeding times by the normal level of platelet vWf ristocetin cofactor activity (vWf activity) and, to a lesser extent, by their platelet vWf antigen content. We have studied the content of adhesive proteins and platelet factor-4 (PF-4), and beta-thromboglobulin (beta TG) in the platelet alpha granules of types I and III vWd patients to determine if other alterations in alpha granule contents of proteins occur in vWd. We found that type I vWd patients with prolonged or normal bleeding times could not be differentiated on the basis of their platelet levels of beta TG, PF-4, fibronectin, or fibrinogen. The levels of the alpha granule constituents in the type I vWd patient were similar to normal except for the platelet fibrinogen concentration. Patients with type I vWd, regardless of the level of platelet vWf activity of antigen, had increased levels of platelet fibrinogen. The patients with type III vWd who had undetectable levels of platelet and plasma vWf also had increased levels of platelet fibrinogen. In our study we could not attribute the variation in the platelet vWf activity and antigen in type I vWd to the size of the alpha granule pool as determined by the measurement of other alpha granule proteins. The mechanism(s) of increased platelet fibrinogen in these vWd patients is at present unknown.
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