Image Rotation Alters Apparent Fibula Length: An Evaluation of Talocrural Angle, Shenton Line, and Dime Sign.

BACKGROUND: Fibula shortening can compromise ankle stability and force transmission, thereby impacting clinical outcomes. Because radiographs depict 3-dimensional anatomy in 2 dimensions, accurate radiographic assessment of fibula length is a commonly encountered clinical challenge. The talocrural angle (TCA), Shenton line, and dime sign are useful parameters of fibula length. Yet, the impact of 3-dimensional limb positioning on these radiographic parameters is not established. METHODS: Bone models were constructed from CT scans of 30 lower limbs. Fibula length was computationally manipulated, and digitally reconstructed radiographs were generated reflecting 1-degree increments of sagittal and axial plane rotation of each limb for each fibula length condition. The TCA was computationally measured on each image. The presence of an aligned mortise view, intact Shenton line, and intact dime sign was assessed by 2 observers. RESULTS: The mean TCA, which was 78.0 (95% CI ± 1.6) degrees for a true mortise projection with anatomic fibula length, changed by approximately 1 degree per millimeter of fibula length change. On average, 14.7 degrees of caudal rotation obscured 2 mm of fibular shortening by virtue of producing the same TCA as a true mortise view with anatomic fibula length, designated a false positive view. Axial rotation had a comparatively small effect. Observers 1 and 2 were, respectively, 91% and 88% less likely to accurately judge the image alignment of the false positive images compared to true mortise images. Moreover, intraobserver agreement was poor to moderate (mean 0.47, range 0.13-0.59) and interobserver agreement was uniformly poor (mean 0.08, range 0.01-0.20). CONCLUSION: In our study using digitally reconstructed radiographs from CT scans of 30 limbs, we found that sagittal plane rotation impacts the radiographic appearance of fibula length as measured by the TCA. Limb axial rotation had a comparatively small effect. Further study of human perception of Shenton line and dime sign is needed before the effect of rotation on these parameters can be fully understood. LEVEL OF EVIDENCE: Level IV, case series.

Mapping the Lobbying Footprint of Harmful Industries: 23 Years of Data From OpenSecrets.

Policy Points Our research reveals the similarities and differences among the lobbying activities of tobacco, alcohol, gambling, and ultraprocessed food industries, which are often a barrier to the implementation of public health policies. Over 23 years, we found that just six organizations dominated lobbying expenses in the tobacco and alcohol sectors, whereas the gambling sector outsourced most of their lobbying to professional firms. Databases like OpenSecrets are a useful resource to monitor the commercial determinants of health. CONTEXT: Commercial lobbying is often a barrier to the development and implementation of public health policies. Yet, little is known about the similarities and differences in the lobbying practices of different industry sectors or types of commercial actors. This study compares the lobbying practices of four industry sectors that have been the focus of much public health research and advocacy: tobacco, alcohol, gambling, and ultraprocessed foods. METHODS: Data on lobbying expenditures and lobbyist backgrounds were sourced from the OpenSecrets database, which monitors lobbying in the United States. Lobbying expenditure data were analyzed for the 1998-2020 period. We classified commercial actors as companies or trade associations. We used Power BI software to link, analyze, and visualize data sets. FINDINGS: We found that the ultraprocessed food industry spent the most on lobbying ($1.15 billion), followed by gambling ($817 million), tobacco ($755 million), and alcohol ($541 million). Overall, companies were more active than trade associations, with associations being least active in the tobacco industry. Spending was often highly concentrated, with two organizations accounting for almost 60% of tobacco spending and four organizations accounting for more than half of alcohol spending. Lobbyists that had formerly worked in government were mainly employed by third-party lobby firms. CONCLUSIONS: Our study shows how comparing the lobbying practices of different industry sectors offers a deeper appreciation of the diversity and similarities of commercial actors. Understanding these patterns can help public health actors to develop effective counterstrategies.

The Center-Center Image Closely Approximates Other Methods for Syndesmosis Reduction Clamp Placement.

BACKGROUND: The optimal placement for a syndesmosis reduction clamp remains an open question. This study compared the center-center axis, which localizes clamp placement using only an internally rotated lateral ankle X-ray, with other common approaches, whose accuracy can only be confirmed using computed tomography (CT). METHODS: Bone models of anatomically aligned (n = 6) and malreduced (n = 48) limbs were generated from CT scans of cadaveric specimens. Four axes for guiding clamp placement (center-center, centroid, B2, and trans-syndesmotic) were then analyzed, using digitally reconstructed radiographs derived from the bone models. Each axis' location was defined using angle-height pairs that describe axis orientation along the full anatomical region where syndesmosis fixation occurs. RESULTS: In anatomically aligned limbs, the center-center axis was located on average (±95% CI [confidence interval]), 0.64° (±0.50°) internal rotation, 1.03° (±0.73°) internal rotation, and 2.09° (±7.29°) external rotation from the centroid, B2, and trans-syndesmotic axes, respectively. Fibular displacement altered the magnitude of limb rotation needed to identify the center-center axis. CONCLUSION: The center-center technique is a valid method that closely approximates previously described methods for syndesmosis clamp placement without using CT, and the magnitude of C-arm rotation needed to transition from a talar dome lateral to a center-center view may be a potential method for assessing syndesmosis reduction. LEVELS OF EVIDENCE: Level III: Retrospective comparative study.

Thymic epithelial cell fate and potency in early organogenesis assessed by single cell transcriptional and functional analysis.

During development, cortical (c) and medullary (m) thymic epithelial cells (TEC) arise from the third pharyngeal pouch endoderm. Current models suggest that within the thymic primordium most TEC exist in a bipotent/common thymic epithelial progenitor cell (TEPC) state able to generate both cTEC and mTEC, at least until embryonic day 12.5 (E12.5) in the mouse. This view, however, is challenged by recent transcriptomics and genetic evidence. We therefore set out to investigate the fate and potency of TEC in the early thymus. Here using single cell (sc) RNAseq we identify a candidate mTEC progenitor population at E12.5, consistent with recent reports. Via lineage-tracing we demonstrate this population as mTEC fate-restricted, validating our bioinformatics prediction. Using potency analyses we also establish that most E11.5 and E12.5 progenitor TEC are cTEC-fated. Finally we show that overnight culture causes most if not all E12.5 cTEC-fated TEPC to acquire functional bipotency, and provide a likely molecular mechanism for this changed differentiation potential. Collectively, our data overturn the widely held view that a common TEPC predominates in the E12.5 thymus, showing instead that sublineage-primed progenitors are present from the earliest stages of thymus organogenesis but that these early fetal TEPC exhibit cell-fate plasticity in response to extrinsic factors. Our data provide a significant advance in the understanding of fetal thymic epithelial development and thus have implications for thymus-related clinical research, in particular research focussed on generating TEC from pluripotent stem cells.

The Haemonchus contortus LGC-39 subunit is a novel subtype of an acetylcholine-gated chloride channel.

The nematode genome exhibits a vast array of Cys-loop receptors that are activated by a diverse set of neurotransmitters and anthelmintic drugs such as ivermectin and levamisole. While many Cys-loop receptors have been functionally and pharmacologically characterized, there remains a large subset of orphan receptors where the agonist remains unknown. We have identified an orphan Cys-loop receptor, LGC-39, from the parasitic nematode Haemonchus contortus that is a novel type of cholinergic-sensitive ligand-gated chloride channel. This receptor groups outside of the acetylcholine-gated chloride channel family, in the previously named GGR-1 (GABA/Glycine Receptor-1) group of Cys-loop receptors. We found that LGC-39 forms a functional homomeric receptor when expressed in Xenopus laevis oocytes and is activated by several cholinergic ligands including acetylcholine, methacholine and surprisingly, atropine with an EC50 for atropine on the low µM range. A homology model was generated which revealed some key features of the LGC-39 ligand-binding pocket that may explain some of the elements important for atropine recognition of the LGC-39 receptor. Overall these results suggest that the GGR-1 family (now called LGC-57) of Cys-loop receptors includes novel acetylcholine-gated chloride channel subtypes and may represent important future drug targets.

Conceptualising commercial entities in public health: beyond unhealthy commodities and transnational corporations.

Most public health research on the commercial determinants of health (CDOH) to date has focused on a narrow segment of commercial actors. These actors are generally the transnational corporations producing so-called unhealthy commodities such as tobacco, alcohol, and ultra-processed foods. Furthermore, as public health researchers, we often discuss the CDOH using sweeping terms such as private sector, industry, or business that lump together diverse entities whose only shared characteristic is their engagement in commerce. The absence of clear frameworks for differentiating among commercial entities, and for understanding how they might promote or harm health, hinders the governance of commercial interests in public health. Moving forward, it is necessary to develop a nuanced understanding of commercial entities that goes beyond this narrow focus, enabling the consideration of a fuller range of commercial entities and the features that characterise and distinguish them. In this paper, which is the second of three papers in a Series on commercial determinants of health, we develop a framework that enables meaningful distinctions among diverse commercial entities through consideration of their practices, portfolios, resources, organisation, and transparency. The framework that we develop permits fuller consideration of whether, how, and to what extent a commercial actor might influence health outcomes. We discuss possible applications for decision making about engagement; managing and mitigating conflicts of interest; investment and divestment; monitoring; and further research on the CDOH. Improved differentiation among commercial actors strengthens the capacity of practitioners, advocates, academics, regulators, and policy makers to make decisions about, to better understand, and to respond to the CDOH through research, engagement, disengagement, regulation, and strategic opposition.

Defining and conceptualising the commercial determinants of health.

Although commercial entities can contribute positively to health and society there is growing evidence that the products and practices of some commercial actors-notably the largest transnational corporations-are responsible for escalating rates of avoidable ill health, planetary damage, and social and health inequity; these problems are increasingly referred to as the commercial determinants of health. The climate emergency, the non-communicable disease epidemic, and that just four industry sectors (ie, tobacco, ultra-processed food, fossil fuel, and alcohol) already account for at least a third of global deaths illustrate the scale and huge economic cost of the problem. This paper, the first in a Series on the commercial determinants of health, explains how the shift towards market fundamentalism and increasingly powerful transnational corporations has created a pathological system in which commercial actors are increasingly enabled to cause harm and externalise the costs of doing so. Consequently, as harms to human and planetary health increase, commercial sector wealth and power increase, whereas the countervailing forces having to meet these costs (notably individuals, governments, and civil society organisations) become correspondingly impoverished and disempowered or captured by commercial interests. This power imbalance leads to policy inertia; although many policy solutions are available, they are not being implemented. Health harms are escalating, leaving health-care systems increasingly unable to cope. Governments can and must act to improve, rather than continue to threaten, the wellbeing of future generations, development, and economic growth.

A proposal for systematic monitoring of the commercial determinants of health: a pilot study assessing the feasibility of monitoring lobbying and political donations in Australia.

BACKGROUND: The commercial determinants of health include a range of practices to promote business interests, often at the expense of public health. Corporate political practices, such as lobbying and campaign donations, are used to influence policy makers and foster a political and regulatory environment conducive to business interests. Despite recognition of their public health importance, thus far there are relatively few efforts to systematically monitor commercial political practices. METHODS: A pilot study was conducted to explore the feasibility of systematically monitoring two political practices - lobbying and political contributions - for 'harmful industries' (alcohol, gambling, ultra-processed food and tobacco industries) in Australia. Potential data sources were reviewed to compare data availability and detail. Two publicly available datasets were selected for the pilot: ministerial diaries for New South Wales and annual donor filings from the Australian Electoral Commission. Google Data Studio was used to analyse and visualise findings.  RESULTS: The pilot study resulted in the creation of several interactive charts and dashboards that supported analysis and interrogation of the data. These charts helped to easily convey the volume of lobbying and political donations, as well as changes over time. For example, we found that between July 2014 and December 2020, NSW ministers had 20,607 meetings, of which 634 meetings were with harmful industries. And between 1998 and 2020, a total of $576,519,472 disclosed donations were made to political parties and other entities, of which $35,823,937 were from harmful industries. CONCLUSIONS: Opportunities to develop a program to monitor commercial political practices face several challenges including access barriers arising from poor availability and detail of data, technical barriers arising from the format of data disclosures and coding challenges arising from the diverse nature of the commercial sector. Despite these challenges, our pilot study demonstrates the potential to implement a monitoring program and to expand its scope to other commercial determinants of health.

Requirement for STAT3 and its target, TFCP2L1, in self-renewal of naïve pluripotent stem cells in vivo and in vitro.

We previously demonstrated gradual loss of epiblast during diapause in embryos lacking components of the LIF/IL6 receptor. Here, we explore the requirement for the downstream signalling transducer andactivator of transcription STAT3 and its target, TFCP2L1, in maintenance of naïve pluripotency. Unlike conventional markers, such as NANOG, which remains high in epiblast until implantation, both STAT3 and TFCP2L1 proteins decline during blastocyst expansion, but intensify in the embryonic region after induction of diapause, as observed visually and confirmed using our image-analysis pipeline, consistent with our previous transcriptional expression data. Embryos lacking STAT3 or TFCP2L1 underwent catastrophic loss of most of the inner cell mass during the first few days of diapause, indicating involvement of signals in addition to LIF/IL6 for sustaining naïve pluripotency in vivo. By blocking MEK/ERK signalling from the morula stage, we could derive embryonic stem cells with high efficiency from STAT3 null embryos, but not those lacking TFCP2L1, suggesting a hitherto unknown additional role for this essential STAT3 target in transition from embryo to embryonic stem cells in vitro. This article has an associated First Person interview with the first author of the paper.

Cell competition and the regulative nature of early mammalian development.

The mammalian embryo exhibits a remarkable plasticity that allows it to correct for the presence of aberrant cells, adjust its growth so that its size is in accordance with its developmental stage, or integrate cells of another species to form fully functional organs. Here, we will discuss the contribution that cell competition, a quality control that eliminates viable cells that are less fit than their neighbors, makes to this plasticity. We will do this by reviewing the roles that cell competition plays in the early mammalian embryo and how they contribute to ensure normal development of the embryo.

Syndesmosis Injury Contributes a Large Negative Effect on Clinical Outcomes: A Systematic Review.

INTRODUCTION: The literature largely addresses questions of diagnostic accuracy and therapeutic accuracy. However, the magnitude of the clinical impact of syndesmosis injury is commonly described in intuitive yet qualitative terms. This systematic review aimed to quantify the impact of syndesmosis injury. METHODS: Published clinical outcomes data were used to compute an effect size reflecting the impact of syndesmosis injury. This was done within the clinical contexts of isolated syndesmosis injury and syndesmosis injury with concomitant ankle fracture. Clinical outcomes data included Olerud-Molander (OM) and American Orthopaedic Foot and Ankle Society (AOFAS) scores, visual analog scale for pain, and days missed from sport competition. Parametric data were compared with Student t tests. Effect size was computed using Cohen's d. RESULTS: In ankle fracture patients, syndesmosis injury demonstrated a large effect size for OM (d = 0.96) and AOFAS (d = 0.83) scores. In athletic populations without concomitant ankle fracture, syndesmosis injury demonstrated a large effect size on days missed from competition (d = 2.32). DISCUSSION: These findings confirm the magnitude of the negative impact of syndesmosis injury in athletic populations with isolated injury and in ankle fracture patients. In ankle fracture patients, this large negative effect remains despite surgery. Thus, syndesmosis repair may not fully mitigate the impact of the injury. LEVELS OF EVIDENCE: Level III: Systematic review.

Pluripotent stem cells related to embryonic disc exhibit common self-renewal requirements in diverse livestock species.

Despite four decades of effort, robust propagation of pluripotent stem cells from livestock animals remains challenging. The requirements for self-renewal are unclear and the relationship of cultured stem cells to pluripotent cells resident in the embryo uncertain. Here, we avoided using feeder cells or serum factors to provide a defined culture microenvironment. We show that the combination of activin A, fibroblast growth factor and the Wnt inhibitor XAV939 (AFX) supports establishment and continuous expansion of pluripotent stem cell lines from porcine, ovine and bovine embryos. Germ layer differentiation was evident in teratomas and readily induced in vitro. Global transcriptome analyses highlighted commonality in transcription factor expression across the three species, while global comparison with porcine embryo stages showed proximity to bilaminar disc epiblast. Clonal genetic manipulation and gene targeting were exemplified in porcine stem cells. We further demonstrated that genetically modified AFX stem cells gave rise to cloned porcine foetuses by nuclear transfer. In summary, for major livestock mammals, pluripotent stem cells related to the formative embryonic disc are reliably established using a common and defined signalling environment. This article has an associated 'The people behind the papers' interview.

Coordinated changes in gene expression kinetics underlie both mouse and human erythroid maturation.

BACKGROUND: Single-cell technologies are transforming biomedical research, including the recent demonstration that unspliced pre-mRNA present in single-cell RNA-Seq permits prediction of future expression states. Here we apply this RNA velocity concept to an extended timecourse dataset covering mouse gastrulation and early organogenesis. RESULTS: Intriguingly, RNA velocity correctly identifies epiblast cells as the starting point, but several trajectory predictions at later stages are inconsistent with both real-time ordering and existing knowledge. The most striking discrepancy concerns red blood cell maturation, with velocity-inferred trajectories opposing the true differentiation path. Investigating the underlying causes reveals a group of genes with a coordinated step-change in transcription, thus violating the assumptions behind current velocity analysis suites, which do not accommodate time-dependent changes in expression dynamics. Using scRNA-Seq analysis of chimeric mouse embryos lacking the major erythroid regulator Gata1, we show that genes with the step-changes in expression dynamics during erythroid differentiation fail to be upregulated in the mutant cells, thus underscoring the coordination of modulating transcription rate along a differentiation trajectory. In addition to the expected block in erythroid maturation, the Gata1-chimera dataset reveals induction of PU.1 and expansion of megakaryocyte progenitors. Finally, we show that erythropoiesis in human fetal liver is similarly characterized by a coordinated step-change in gene expression. CONCLUSIONS: By identifying a limitation of the current velocity framework coupled with in vivo analysis of mutant cells, we reveal a coordinated step-change in gene expression kinetics during erythropoiesis, with likely implications for many other differentiation processes.

The transcription factor Rreb1 regulates epithelial architecture, invasiveness, and vasculogenesis in early mouse embryos.

Ras-responsive element-binding protein 1 (Rreb1) is a zinc-finger transcription factor acting downstream of RAS signaling. Rreb1 has been implicated in cancer and Noonan-like RASopathies. However, little is known about its role in mammalian non-disease states. Here, we show that Rreb1 is essential for mouse embryonic development. Loss of Rreb1 led to a reduction in the expression of vasculogenic factors, cardiovascular defects, and embryonic lethality. During gastrulation, the absence of Rreb1 also resulted in the upregulation of cytoskeleton-associated genes, a change in the organization of F-ACTIN and adherens junctions within the pluripotent epiblast, and perturbed epithelial architecture. Moreover, Rreb1 mutant cells ectopically exited the epiblast epithelium through the underlying basement membrane, paralleling cell behaviors observed during metastasis. Thus, disentangling the function of Rreb1 in development should shed light on its role in cancer and other diseases involving loss of epithelial integrity.

Metabolic control of DNA methylation in naive pluripotent cells.

Naive epiblast and embryonic stem cells (ESCs) give rise to all cells of adults. Such developmental plasticity is associated with genome hypomethylation. Here, we show that LIF-Stat3 signaling induces genomic hypomethylation via metabolic reconfiguration. Stat3-/- ESCs show decreased α-ketoglutarate production from glutamine, leading to increased Dnmt3a and Dnmt3b expression and DNA methylation. Notably, genome methylation is dynamically controlled through modulation of α-ketoglutarate availability or Stat3 activation in mitochondria. Alpha-ketoglutarate links metabolism to the epigenome by reducing the expression of Otx2 and its targets Dnmt3a and Dnmt3b. Genetic inactivation of Otx2 or Dnmt3a and Dnmt3b results in genomic hypomethylation even in the absence of active LIF-Stat3. Stat3-/- ESCs show increased methylation at imprinting control regions and altered expression of cognate transcripts. Single-cell analyses of Stat3-/- embryos confirmed the dysregulated expression of Otx2, Dnmt3a and Dnmt3b as well as imprinted genes. Several cancers display Stat3 overactivation and abnormal DNA methylation; therefore, the molecular module that we describe might be exploited under pathological conditions.

A Case of Paraneoplastic Myoclonus Attributed to Non-Small Cell Lung Cancer.

Background: It is well known that myoclonus can be a paraneoplastic manifestation of underlying malignancy. Case Report: A 78-year-old male diagnosed with papillary variant non-small cell lung cancer (NSCLC) presented with tremulousness that rapidly evolved into severe, diffuse myoclonus with prominent palatal involvement requiring intubation. The generalized myoclonus resolved with on levetiracetam, chemotherapy and immune modulation. While low titer positive P/Q type calcium channel autoantibodies were detected, it's etiologic relevance is unclear. Discussion: This case highlights a rare neurologic paraneoplastic presentation of papillary NSCLC. It also illustrates the importance of monitoring airway safety when myoclonus is generalized. Highlights: A new, rare paraneoplastic presentation of papillary variant non-small cell lung adenocarcinoma is described. The patient presented with severe diffuse myoclonus with prominent palatal involvement without encephalitis that responded to a combination of chemotherapy, immune modulation, and levetiracetam. No clear causal antibody was found.

Computed Tomographic Validation of the Center-Center Radiographic Technique for Syndesmosis Fixation Axis Alignment in Normal Ankles.

BACKGROUND: Ankle syndesmotic ligament injury is an important factor affecting clinical outcome after lower extremity injury with as little as 2 mm of syndesmotic displacement leading to worse clinical outcome. One important factor is the appropriate placement of clamps and fixation across the syndesmosis. When not ideally aligned, these can result in malalignment of the fibula in the incisura. This study sought to provide computer validation of using the center-center technique to identify an ideal centroid axis for placement of syndesmotic implants. METHODS: Thirty computed tomography (CT) scans of patients from July 1, 2016, to June 30, 2018, with normal syndesmoses were evaluated. Center-center and centroid measurements were drawn and compared on the axial CT images at 10, 20, and 30 mm superior to the tibial plafond. Three observers recorded measurements for the same 50 patients in order to compare interobserver reliability. RESULTS: The difference between the centroid and center-center axis at each height level was a mean 0.4 degrees (range, 0.3-0.5 degrees). The center-center and centroid axis change by externally rotating as the height increases away from the tibial plafond with mean, 3 degrees (range, 0-6.1 degrees). Intraclass correlation coefficients (ICCs) were measured at 0.98, thus demonstrating excellent intraobserver and interobserver reliability on these measurements. CONCLUSION: The center-center technique can be used to identify the centroid axis within an acceptable degree of rotation at heights above the tibial plafond that are relevant to an operating surgeon placing syndesmotic fixation. CLINICAL RELEVANCE: Theoretically, this aligns the centroids of the fibula and tibia, which achieves the same ideal patient-specific alignment and raises the question as to the extent to which the centroid and center-center axes correlate in the general population. If present, a strong correlation has potentially high clinical importance when planning syndesmotic fixation.

Annotation: The COVID-19 pandemic and clinical orthopaedic and trauma surgery.

This article provides a brief overview of the current COVID-19 pandemic crisis and the impact on trauma and orthopaedic surgeons. The principles of protect, avoid, restrict and abbreviate are recommended. Coordination of response, communication and support are also important. The versatility of orthopaedic surgeons lends them to having an important role.

A New Species of Sucking Louse from the Mandrill from Gabon with a Review of Host Associations and Geographical Distributions, and Identification Keys to Members of the Genus pedicinus (Phthiraptera: Anoplura: Pedicinidae).

Members of the sucking louse genus Pedicinus are ectoparasites of cercopithecid primates in Africa, Asia, and Gibraltar. Pedicinus gabonensis n. sp. is described on the basis of adult male and female specimens collected from the mandrill (Mandrillus sphinx) in Gabon. The new species is compared morphologically with other members of the genus Pedicinus, and a nuclear elongation factor 1 alpha gene sequence is provided. Host associations and geographical distributions of the 18 previously recognized species of the genus and of P. gabonensis n. sp. are reviewed. Updated identification keys are provided for males and females of all known valid species of Pedicinus.