Metric-Scale Truncation-Robust Heatmaps for 3D Human Pose Estimation

Heatmap representations have formed the basis of 2D human pose estimation systems for many years, but their generalizations for 3D pose have only recently been considered. This includes 2.5D volumetric heatmaps, whose X and Y axes correspond to image space and the Z axis to metric depth around the subject. To obtain metric-scale predictions, these methods must include a separate, explicit post-processing step to resolve scale ambiguity. Further, they cannot encode body joint positions outside of the image boundaries, leading to incomplete pose estimates in case of image truncation. We address these limitations by proposing metric-scale truncation-robust (MeTRo) volumetric heatmaps, whose dimensions are defined in metric 3D space near the subject, instead of being aligned with image space. We train a fully-convolutional network to estimate such heatmaps from monocular RGB in an end-to-end manner. This reinterpretation of the heatmap dimensions allows us to estimate complete metric-scale poses without test-time knowledge of the focal length or person distance and without relying on anthropometric heuristics in post-processing. Furthermore, as the image space is decoupled from the heatmap space, the network can learn to reason about joints beyond the image boundary. Using ResNet-50 without any additional learned layers, we obtain state-of-the-art results on the Human3.6M and MPI-INF-3DHP benchmarks. As our method is simple and fast, it can become a useful component for real-time top-down multi-person pose estimation systems. We make our code publicly available to facilitate further research (see https://vision.rwth-aachen.de/metro-pose3d).Comment: Accepted for publication at the 2020 IEEE Conference on Automatic Face and Gesture Recognition (FG

MeTRAbs: Metric-Scale Truncation-Robust Heatmaps for Absolute 3D Human Pose Estimation

Heatmap representations have formed the basis of human pose estimation systems for many years, and their extension to 3D has been a fruitful line of recent research. This includes 2.5D volumetric heatmaps, whose X and Y axes correspond to image space and Z to metric depth around the subject. To obtain metric-scale predictions, 2.5D methods need a separate post-processing step to resolve scale ambiguity. Further, they cannot localize body joints outside the image boundaries, leading to incomplete estimates for truncated images. To address these limitations, we propose metric-scale truncation-robust (MeTRo) volumetric heatmaps, whose dimensions are all defined in metric 3D space, instead of being aligned with image space. This reinterpretation of heatmap dimensions allows us to directly estimate complete, metric-scale poses without test-time knowledge of distance or relying on anthropometric heuristics, such as bone lengths. To further demonstrate the utility our representation, we present a differentiable combination of our 3D metric-scale heatmaps with 2D image-space ones to estimate absolute 3D pose (our MeTRAbs architecture). We find that supervision via absolute pose loss is crucial for accurate non-root-relative localization. Using a ResNet-50 backbone without further learned layers, we obtain state-of-the-art results on Human3.6M, MPI-INF-3DHP and MuPoTS-3D. Our code will be made publicly available to facilitate further research.Comment: See project page at https://vision.rwth-aachen.de/metrabs . Accepted for publication in the IEEE Transactions on Biometrics, Behavior, and Identity Science (TBIOM), Special Issue "Selected Best Works From Automated Face and Gesture Recognition 2020". Extended version of FG paper arXiv:2003.0295

Deletion of TOP3β, a component of FMRP-containing mRNPs, contributes to neurodevelopmental disorders

Implicating particular genes in the generation of complex brain and behavior phenotypes requires multiple lines of evidence. The rarity of most high impact genetic variants typically precludes the possibility of accruing statistical evidence that they are associated with a given trait. We show here that the enrichment of a rare Chromosome 22q11.22 deletion in a recently expanded Northern Finnish sub-isolate enables the detection of association between TOP3β and both schizophrenia and cognitive impairment. Biochemical analysis of TOP3β revealed that this topoisomerase is a component of cytosolic messenger ribonucleoproteins (mRNPs) and is catalytically active on RNA. The recruitment of TOP3β to mRNPs was independent of RNA cis-elements and was coupled to the co-recruitment of FMRP, the disease gene product in fragile X mental retardation syndrome (FXS). Thus, we uncover a novel role for TOP3β in mRNA metabolism and provide several lines of evidence implicating it in neurodevelopmental disorders

Automated telephone communication systems for preventive healthcare and management of long-term conditions

Background Automated telephone communication systems (ATCS) can deliver voice messages and collect health-related information from patients using either their telephone’s touch-tone keypad or voice recognition software. ATCS can supplement or replace telephone contact between health professionals and patients. There are four different types of ATCS: unidirectional (one-way, non-interactive voice communication), interactive voice response (IVR) systems, ATCS with additional functions such as access to an expert to request advice (ATCS Plus) and multimodal ATCS, where the calls are delivered as part of a multicomponent intervention. Objectives To assess the effects of ATCS for preventing disease and managing long-term conditions on behavioural change, clinical, process, cognitive, patient-centred and adverse outcomes. Search methods We searched 10 electronic databases (the Cochrane Central Register of Controlled Trials; MEDLINE; Embase; PsycINFO; CINAHL; Global Health; WHOLIS; LILACS; Web of Science; and ASSIA); three grey literature sources (Dissertation Abstracts, Index to Theses, Australasian Digital Theses); and two trial registries (www.controlled-trials.com; www.clinicaltrials.gov) for papers published between 1980 and June 2015. Selection criteria Randomised, cluster- and quasi-randomised trials, interrupted time series and controlled before-and-after studies comparing ATCS interventions, with any control or another ATCS type were eligible for inclusion. Studies in all settings, for all consumers/carers, in any preventive healthcare or long term condition management role were eligible. Data collection and analysis We used standard Cochrane methods to select and extract data and to appraise eligible studies. Main results We included 132 trials (N = 4,669,689). Studies spanned across several clinical areas, assessing many comparisons based on evaluation of different ATCS types and variable comparison groups. Forty-one studies evaluated ATCS for delivering preventive healthcare, 84 for managing long-term conditions, and seven studies for appointment reminders. We downgraded our certainty in the evidence primarily because of the risk of bias for many outcomes. We judged the risk of bias arising from allocation processes to be low for just over half the studies and unclear for the remainder. We considered most studies to be at unclear risk of performance or detection bias due to blinding, while only 16% of studies were at low risk. We generally judged the risk of bias due to missing data and selective outcome reporting to be unclear. For preventive healthcare, ATCS (ATCS Plus, IVR, unidirectional) probably increase immunisation uptake in children (risk ratio (RR) 1.25, 95% confidence interval (CI) 1.18 to 1.32; 5 studies, N = 10,454; moderate certainty) and to a lesser extent in adolescents (RR 1.06, 95% CI 1.02 to 1.11; 2 studies, N = 5725; moderate certainty). The effects of ATCS in adults are unclear (RR 2.18, 95% CI 0.53 to 9.02; 2 studies, N = 1743; very low certainty). For screening, multimodal ATCS increase uptake of screening for breast cancer (RR 2.17, 95% CI 1.55 to 3.04; 2 studies, N = 462; high certainty) and colorectal cancer (CRC) (RR 2.19, 95% CI 1.88 to 2.55; 3 studies, N = 1013; high certainty) versus usual care. It may also increase osteoporosis screening. ATCS Plus interventions probably slightly increase cervical cancer screening (moderate certainty), but effects on osteoporosis screening are uncertain. IVR systems probably increase CRC screening at 6 months (RR 1.36, 95% CI 1.25 to 1.48; 2 studies, N = 16,915; moderate certainty) but not at 9 to 12 months, with probably little or no effect of IVR (RR 1.05, 95% CI 0.99, 1.11; 2 studies, 2599 participants; moderate certainty) or unidirectional ATCS on breast cancer screening. Appointment reminders delivered through IVR or unidirectional ATCS may improve attendance rates compared with no calls (low certainty). For long-term management, medication or laboratory test adherence provided the most general evidence across conditions (25 studies, data not combined). Multimodal ATCS versus usual care showed conflicting effects (positive and uncertain) on medication adherence. ATCS Plus probably slightly (versus control; moderate certainty) or probably (versus usual care; moderate certainty) improves medication adherence but may have little effect on adherence to tests (versus control). IVR probably slightly improves medication adherence versus control (moderate certainty). Compared with usual care, IVR probably improves test adherence and slightly increases medication adherence up to six months but has little or no effect at longer time points (moderate certainty). Unidirectional ATCS, compared with control, may have little effect or slightly improve medication adherence (low certainty). The evidence suggested little or no consistent effect of any ATCS type on clinical outcomes (blood pressure control, blood lipids, asthma control, therapeutic coverage) related to adherence, but only a small number of studies contributed clinical outcome data. The above results focus on areas with the most general findings across conditions. In condition-specific areas, the effects of ATCS varied, including by the type of ATCS intervention in use. Multimodal ATCS probably decrease both cancer pain and chronic pain as well as depression (moderate certainty), but other ATCS types were less effective. Depending on the type of intervention, ATCS may have small effects on outcomes for physical activity, weight management, alcohol consumption, and diabetes mellitus. ATCS have little or no effect on outcomes related to heart failure, hypertension, mental health or smoking cessation, and there is insufficient evidence to determine their effects for preventing alcohol/ substance misuse or managing illicit drug addiction, asthma, chronic obstructive pulmonary disease, HIV/AIDS, hypercholesterolaemia, obstructive sleep apnoea, spinal cord dysfunction or psychological stress in carers. Only four trials (3%) reported adverse events, and it was unclear whether these were related to the intervention

Systemic splicing factor deficiency causes tissue-specific defects: a zebrafish model for retinitis pigmentosa

Retinitis pigmentosa (RP) ist eine vererbte Form der Erblindung, die durch eine progressive Degeneration von Photorezeptorzellen in der Retina verursacht wird. Neben „klassischen“ RP-Krankheitsgenen, die direkt oder indirekt mit dem Sehprozess und der Aufrechterhaltung der Photorezeptoren in Verbindung stehen, können auch Mutationen in Genen für konstitutive Spleißfaktoren zur Photorezeptordegeneration führen. RP kann daher als Paradebeispiel einer Erkrankung mit paradoxer Gewebespezifität angesehen werden: Defekte in essentiellen und ubiquitär exprimierten Genen führen zu einem Phänotyp, der nur wenige Zelltypen betrifft. Um Einblicke in diesen außergewöhnlichen Pathomechanismus zu erhalten, wurde im Rahmen der vorliegenden Arbeit ein Tiermodell für Spleißfaktor-vermittelte RP im Zebrafisch Danio rerio etabliert. Zunächst wurde gezeigt, dass eine RP verursachende Punktmutation des Spleißfaktors Prpf31 auch in dessen Zebrafisch-Homolog zu einem Verlust der physiologischen Aktivität führt. Als Modell für die Prpf31-Mangelsituation diente dann die durch ein Antisense-Morpholino induzierte partielle Reduktion der Prpf31-Expression in Zebrafischlarven. Konsistent mit einem RP-Phänotyp zeigte sich in diesen Larven eine starke Beeinträchtigung des Sehvermögens. Sie wurde – ebenfalls analog zu RP – durch defekte Photorezeptoren verursacht, die bei ansonsten normal entwickelter Retina eine deutlich veränderte Morphologie aufwiesen. Daraufhin konnten in einer genomweiten Transkriptomanalyse der Augen von Prpf31-defizienten Larven erstmals in vivo photorezeptorspezifische Gene identifiziert werden, deren Expression durch den Mangel an Prpf31 beeinträchtigt war. Im zweiten Teil der Arbeit wurde untersucht, ob es neben den bereits bekannten RP-Krankheitsgenen weitere Spleißfaktoren gibt, deren Defekt die Degeneration von Photorezeptoren auslösen kann. Dazu wurde in Zebrafischlarven ein Mangel an Prpf4 erzeugt, einem Spleißfaktor, der bislang nicht mit RP in Verbindung gebracht worden war. Der Phänotyp dieser Fische war nicht von dem des Prpf31 RP-Modells zu unterscheiden. Dies lieferte einen Hinweis darauf, dass auch Defekte in Prpf4 in der Lage sein könnten, RP auszulösen. Tatsächlich konnte durch genetisches Screening ein RP-Patient mit einer Punktmutation in Prpf4 identifiziert werden (Kollaboration mit Hanno Bolz, Universität Köln). Die biochemische Analyse dieser Mutation zeigte, dass sie zu einem Defekt der Integration von Prpf4 in spleißosomale Untereinheiten und zu dessen Funktionsverlust in vivo führt. Mit dem in dieser Arbeit etablierten Tiermodell konnte zum ersten Mal in vivo ein von Spleißfaktor-Mutationen verursachter Pathomechanismus von Retinitis pigmentosa nachvollzogen werden. Die vom Prpf31-Mangel betroffenen Photorezeptortranskripte stellen vielversprechende Kandidaten für die Vermittlung der Gewebespezifität dar und unterstützen die Hypothese, dass ihre ineffiziente Prozessierung den RP-Phänotyp auslöst. Die Entdeckung eines weiteren Spleißfaktors, dessen Defizienz ebenfalls zu defekten Photorezeptoren führt, zeigt, dass offenbar der Funktionsverlust des Spleißosoms generell in der Lage ist, die Degeneration dieser Zellen zu verursachen. Dies ist nicht zuletzt auch von klinischer Relevanz, da vermutet werden kann, dass sich unter den vielen bisher nicht identifizierten RP-Krankheitsgenen weitere Spleißfaktoren befinden.Retinitis pigmentosa (RP) is a hereditary eye disease marked by the progressive degeneration of photoreceptor cells in the retina. Typical RP disease gene products are involved in visual function or photoreceptor maintenance. However, also mutations in constitutive splicing factors have been shown to cause this type of photoreceptor degeneration. In humans, almost all transcripts need to be processed by the spliceosome and hence its constitutive components are considered to be essential in all cells of the body. RP therefore serves as a paradigm for diseases with a tissue specificity paradox: Defects in essential and ubiquitously expressed genes lead to a phenotype that affects only a small subset of cells or tissues. To gain insight into this unusual etiology, an animal model for splicing factor-linked RP was established in the zebrafish Danio rerio. First, it was shown that an RP-causing missense mutation in the splicing factor Prpf31 leads to a loss of its physiological activity not only in humans, but likewise in zebrafish. The resulting splicing factor deficiency was then modeled in zebrafish embryos by the injection of an antisense morpholino that blocked Prpf31 translation. Consistent with an RP-like phenotype, partial silencing of Prpf31 led to a marked reduction in visual function. This was – again similar to what is observed in RP – caused by severe photoreceptor defects, as these cells presented a highly aberrant morphology in an otherwise normal retina. Consequently, a genome-wide transcriptome analysis of these animals for the first time resulted in the identification of photoreceptor-specific transcripts which show altered expression in vivo due to Prpf31 deficiency. The second part of this work followed the hypothesis that mutations in other splicing factors may likewise elicit photoreceptor degeneration. Therefore, the splicing factor Prpf4, which was not linked to RP prior to this work, was silenced in zebrafish embryos by the injection of an antisense morpholino. The phenotype of these fish was indistinguishable from the Prpf31 RP-model. Defects in Prpf4 might hence be able to cause the degeneration of photoreceptors. Consistent with this, an RP patient with a missense mutation of Prpf4 was identified (in collaboration with Hanno Bolz, University of Cologne). The biochemical analysis of this mutation revealed that it leads to a defect in the integration of Prpf4 into spliceosomal subunits and to its loss of function in vivo. The animal model established in this work for the first time allowed studying the etiology of splicing factor-linked RP in photoreceptors in vivo. The photoreceptor transcripts affected by Prpf31 deficiency are promising candidates for mediating the tissue-specificity of the disease and support the hypothesis that their inefficient processing triggers the RP-phenotype. The identification of another splicing factor, whose deficiency leads to defective photoreceptors, shows that a loss of spliceosomal function in general is able to cause the degeneration of these cells. This is also of clinical relevance, as it shows that the large list of unknown RP disease genes might include even more splicing factors

mRNA metabolism and neuronal disease

To serve as templates for translation eukaryotic mRNAs undergo an elaborate processing and maturation pathway. In eukaryotes this process comprises the synthesis of mRNA precursors, their processing and transport to the site of translation and eventually their decay. During the entire life cycle, mRNAs interact with distinct sets of trans-acting factors that determine their fate at any given phase of gene expression. Recent studies have shown that mutations in components acting in trans on mRNAs are frequent causes of a large variety of different human disorders. The etiology of most of these diseases is, however, only poorly understood, mostly because the consequences for mRNA-metabolism are unclear. Here we discuss three prominent genetic diseases that fall into this category, namely spinal muscular atrophy (SMA), retinitis pigmentosa (RP) and X-linked syndromic mental retardation (XLMR). Whereas SMA and RP can be directly linked to mRNA processing, XLMR results from mutations in the mRNA surveillance system. We discuss how defects in mRNA maturation and turnover might lead to the tissue specific defects seen in these diseases. (C) 2015 Federation of European Biochemical Societies. Published by Elsevier B.V. All rights reserved