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Janosch A Priebe,1 Linda Kerkemeyer,2 Katharina K Haas,1 Katharina Achtert,2 Leida F Moreno Sanchez,1,3 Paul Stockert,1 Maximilian Spannagl,1 Julia Wendlinger,1 Reinhard Thoma,4 Siegfried Ulrich Jedamzik,3 Jan Reichmann,5 Sebastian Franke,6 Leonie Sundmacher,6 Volker E Amelung,2 Thomas R Toelle1 1Center of Interdisciplinary Pain Medicine, Department of Neurology, Klinikum Rechts der Isar, Technical University of Munich (TUM), Munich, Germany; 2Institute for Applied Health Services Research, Inav GmbH, Berlin, Germany; 3Bayerische TelemedAllianz, Ingolstadt, Baar-Ebenhausen, Germany; 4Pain Clinic, Algesiologikum Pain Center, Munich, Germany; 5StatConsult GmbH Magdeburg, Magdeburg, Germany; 6Department of Health Economics, Faculty of Sports and Health Sciences, Technical University of Munich (TUM), Munich, GermanyCorrespondence: Thomas R Toelle, Center of Interdisciplinary Pain Medicine, Department of Neurology, Klinikum rechts der Isar, Technical University of Munich (TUM), Ismaninger Str. 22, Munich, 81675, Germany, Tel +49-89-4140-4613, Email thomas.toelle@tum.dePurpose: Non-specific low back pain (NLBP) exerts a profound impact on global health and economics. In the era of Web 3.0, digital therapeutics offer the potential to improve NLBP management. The Rise-uP trial introduces a digitally anchored, general practitioner (GP)-focused back pain management approach with the Kaia back pain app as the key intervention. Here, we present the 12-months evaluation of the Rise-uP trial including clinical and economic outcomes, patient satisfaction and behavioral tracking analysis.Methods: The cluster-randomized controlled study (registration number: DRKS00015048) enrolled 1237 patients, with 930 receiving treatment according to the Rise-uP approach and 307 subjected to standard of care treatment. Assessments of pain, psychological state, functional capacity, and well-being (patient-reported outcome measures; PROMs) were collected at baseline, and at 3-, 6-, and 12-months follow-up intervals. Health insurance partners AOK, DAK, and BARMER provided individual healthcare cost data. An artificial intelligence (AI)-driven behavioral tracking analysis identified distinct app usage clusters that presented all with about the same clinical outcome. Patient satisfaction (patient-reported experience measures; PREMs) was captured at the end of the trial.Results: Intention-to-treat (ITT) analysis demonstrated that the Rise-uP group experienced significantly greater pain reduction at 12 months compared to the control group (IG: − 46% vs CG: − 24%; p < 0.001) with only the Rise-uP group achieving a pain reduction that was clinically meaningful. Improvements in all other PROMs were notably superior in patients of the Rise-uP group. The AI analysis of app usage discerned four usage clusters. Short- to long-term usage, all produced about the same level of pain reduction. Cost-effectiveness analysis indicated a substantial economic benefit for Rise-uP.Conclusion: The Rise-uP approach with a medical multimodal back pain app as the central element of digital treatment demonstrates both, clinical and economic superiority compared to standard of care in the management of NLBP.Keywords: digital medicine, medical apps, non-specific low back pain, multimodal pain therapy, healthcare costs, behavioral tracking analysis

Janosch A Priebe,1 Katharina K Haas,1 Leida F Moreno Sanchez,1,2 Karin Schoefmann,1 Daniel A Utpadel-Fischler,1 Paul Stockert,1 Reinhard Thoma,3 Christine Schiessl,3 Linda Kerkemeyer,4 Volker Amelung,4 Siegfried Jedamzik,2 Jan Reichmann,5 Ursula Marschall,6 Thomas R Toelle1 1Center of Interdisciplinary Pain Medicine, Department of Neurology, Klinikum Rechts der Isar, Technical University of Munich, Munich, Germany; 2Bayerische TelemedAllianz (BTA), Ingolstadt, Germany; 3Pain Clinic, Algesiologikum Pain Center, Munich, Germany; 4Institute for Applied Health Services Research, inav GmbH, Berlin, Germany; 5StatConsult GmbH Magdeburg, Magdeburg, Germany; 6Barmer Hauptverwaltung, Wuppertal, GermanyCorrespondence: Thomas R ToelleCenter of Interdisciplinary Pain Medicine, Department of Neurology, Klinikum Rechts der Isar, Technische Universität München, Ismaninger Str. 22, Munich 81675, GermanyTel +49-89-4140-4613Email thomas.toelle@tum.dePurpose: Non-specific low back pain (NLBP) causes an enormous burden to patients and tremendous costs for health care systems worldwide. Frequently, treatments are not oriented to existing guidelines. In the future, digital elements may be promising tools to support guideline-oriented treatment in a broader range of patients. The cluster-randomized controlled “Rise-uP” trial aims to support a General Practitioner (GP)-centered back pain treatment (Registration No: DRKS00015048) and includes the following digital elements: 1) electronic case report form (eCRF), 2) a treatment algorithm for guideline-based clinical decision making of GPs, 3) teleconsultation between GPs and pain specialists for patients at risk for development of chronic back pain, and 4) a multidisciplinary mobile back pain app for all patients (Kaia App).Methods: In the Rise-uP trial, 111 GPs throughout Bavaria (southern Germany) were randomized either to the Rise-uP intervention group (IG) or the control group (CG). Rise-uP patients were treated according to the guideline-oriented Rise-uP treatment algorithm. Standard of care was applied to the CG patients with consideration given to the “National guideline for the treatment of non-specific back pain”. Pain rating on the numeric rating scale was the primary outcome measure. Psychological measures (anxiety, depression, stress), functional ability, as well as physical and mental wellbeing, served as secondary outcomes. All values were assessed at the beginning of the treatment and at 3-month follow-ups.Results: In total, 1245 patients (IG: 933; CG: 312) with NLBP were included in the study. The Rise-uP group showed a significantly stronger pain reduction compared to the control group after 3 months (IG: M=− 33.3% vs CG: M=− 14.3%). The Rise-uP group was also superior in secondary outcomes. Furthermore, high-risk patients who received a teleconsultation showed a larger decrease in pain intensity (− 43.5%) than CG patients (− 14.3%). ANCOVA analysis showed that the impact of teleconsultation was mediated by an increased training activity in the Kaia App.Conclusion: Our results show the superiority of the innovative digital treatment algorithm realized in Rise-uP, even though the CG also received relevant active treatment by their GPs. This provides clear evidence that digital treatment may be a promising tool to improve the quality of treatment of non-specific back pain. In 2021, analyses of routine data from statutory health insurances will enable us to investigate the cost-effectiveness of digital treatment.Keywords: NLBP, eHealth, mHealth, digital medicine, guideline-oriented treatment, chronic pain, STarT Back

James P ReichmannSales & Marketing, American HomePatient, Brentwood, TN, USA, I would like to congratulate the authors of the article entitled, "Optimal management of nausea and vomiting of pregnancy" for the comprehensive review of treatments for a frequent complication of pregnancy.1 Although this letter arrives well after publication I think it is important for researchers in the future to have clarification on one seemingly minor but important point. In order to avoid confusion it must be pointed out that in the metoclopramide section the statement "subcutaneous metoclopramide is effective in many women with NVP and HG" is supported by one observational trial on continuous subcutaneous metoclopramide.2 This distinction is very important because that study reported patients were receiving the drug for 26.7 days on average at a cost of $4432 per patient. Unfavorable cost comparisons have been previously published.3 The recommendation that more studied and less expensive alternatives are explored prior to subjecting the patient to this extreme measure seems prudent.4 Perhaps the use of the reference to continuous subcutaneous metoclopramide may have been accidental but the suggestion that "these findings are reassuring, especially for women who experience excessive sleepiness…" implies that women on Diclectin® who report being tired are advanced to continuous subcutaneous metoclopramide seems like a waste of health care resources and a little reckless.1View original paper by Ebrahimi and colleagues.

Understanding vibrissal transduction has advanced by serial sectioning and identified afferent recordings, but afferent mapping onto the complex, encapsulated follicle remains unclear. Here, we reveal male rat C2 vibrissa follicle innervation through synchrotron X-ray phase contrast tomograms. Morphological analysis identified 5% superficial, ~32 % unmyelinated and 63% myelinated deep vibrissal nerve axons. Myelinated afferents consist of each one third Merkel and club-like, and one sixth Ruffini-like and lanceolate endings. Unsupervised clustering of afferent properties aligns with classic morphological categories and revealed previously unrecognized club-like afferent subtypes distinct in axon diameter and Ranvier internode distance. Myelination and axon diameters indicate a proximal-to-distal axon-velocity gradient along the follicle. Axons innervate preferentially dorso-caudally to the vibrissa, presumably to sample contacts from vibrissa protraction. Afferents organize in axon-arms innervating discrete angular territories. The radial axon-arm arrangement around the vibrissa maps into a linear representation of axon-arm bands in the nerve. Such follicle linearization presumably instructs downstream linear brainstem barrelettes. Synchrotron imaging provides a synopsis of afferents and mechanotransductory machinery., Competing Interests: Competing interests: The authors declare no competing interests., (© 2025. The Author(s).)

Determining whether preoperative performance-based knee function predicts postoperative performance-based knee function and whether patient-reported outcome measures (PROMs) completed by participants can detect these changes could significantly enhance the planning of postoperative rehabilitation for patients following total knee arthroplasty (TKA). This study aims to collect data on performance-based knee function using inertial measurement units (IMUs) worn by participants both preoperatively and postoperatively. PROMs will be completed by the patients before and after surgery to assess their ability to detect the same changes in performance-based knee function measured by the sensors. Additionally, the study will investigate the correlation between the degree of knee alignment correction and postoperative performance-based knee function in participants after TKA.

X-ray Phase Contrast Tomography (XPCT) based on wavefield propagation has been established as a high resolution three-dimensional (3D) imaging modality, suitable to reconstruct the intricate structure of soft tissues, and the corresponding pathological alterations. However, for biomedical research, more is needed than 3D visualisation and rendering of the cytoarchitecture in a few selected cases. First, the throughput needs to be increased to cover a statistically relevant number of samples. Second, the cytoarchitecture has to be quantified in terms of morphometric parameters, independent of visual impression. Third, dimensionality reduction and classification are required for identification of effects and interpretation of results. To address these challenges, we here design and implement a novel integrated and high throughput XPCT imaging and analysis workflow for 3D histology, pathohistology and drug testing. Our approach uses semi-automated data acquisition, reconstruction and statistical quantification. We demonstrate its capability for the example of lung pathohistology in Covid-19. Using a small animal model, different Covid-19 drug candidates are administered after infection and tested in view of restoration of the physiological cytoarchitecture, specifically the alveolar morphology. To this end, we then use morphometric parameter determination followed by a dimensionality reduction and classification based on optimal transport. This approach allows efficient discrimination between physiological and pathological lung structure, thereby providing quantitative insights into the pathological progression and partial recovery due to drug treatment. Finally, we stress that the XPCT image chain implemented here only used synchrotron radiation for validation, while the data used for analysis was recorded with laboratory μ CT radiation, more easily accessible for pre-clinical research., (© 2024. The Author(s).)

A minimal diffusion barrier is key to the pulmonary gas exchange. In alveolar capillary dysplasia (ACD), a rare genetically driven disease of early infancy, this crucial fibrovascular interface is compromised while the underlying pathophysiology is insufficiently understood. Recent in-depth analyses of vascular alterations in adult lung disease encouraged researchers to extend these studies to ACD and compare the changes of the microvasculature. Lung tissue samples of children with ACD (n = 12), adults with non-specific interstitial pneumonia (n = 12), and controls (n = 20) were studied using transmission electron microscopy, single-gene sequencing, immunostaining, exome sequencing, and broad transcriptome profiling. In ACD, pulmonary capillary basement membranes were hypertrophied, thickened, and multilamellated. Transcriptome profiling revealed increased CDH5, COL4A1, COL15A1, PTK2B, and FN1 and decreased VIT expression, confirmed by immunohistochemistry. In contrast, non-specific interstitial pneumonia samples showed a regular basement membrane architecture with preserved VIT expression but also increased COL15A1 + vessels. This study provides insight into the ultrastructure and pathophysiology of ACD. The lack of normally developed lung capillaries appeared to cause a replacement by COL15A1 + vessels, a mechanism recently described in interstitial lung disease. The VIT loss and FN1 overexpression might contribute to the unique appearance of basement membranes in ACD. Future studies are needed to explore the therapeutic potential of down-regulating the expression of FN1 and balancing VIT deficiency., Competing Interests: Disclosure Statement J.C.S. received fees for lectures from Boehringer Ingelheim and Kinevant, all outside the present study. T.W. declares funding by the German Ministry of Research and Education. M.M.H. received fees for lectures and consultations from Acceleron, Actelion, AOP, Bayer, Janssen, MSD, and Pfizer, all outside the present study. J.F. received personal fees/speaker honoraria from AstraZeneca, outside the submitted work. M.G. received fees for lectures from Boehringer Ingelheim, participates in an adjudication board in a nintedanib clinical trial, and received a research grant from Boehringer Ingelheim. D.D.J. received fees for lectures from Boehringer Ingelheim and declares a research contract with Boehringer Ingelheim (contract number 43099358). All other authors declare no existing conflicts of interest., (Copyright © 2024 American Society for Investigative Pathology. Published by Elsevier Inc. All rights reserved.)

Inertial measurement units (IMUs) are increasingly being used to assess knee function. The aim of the study was to record patients' activity levels and to detect new parameters for knee function in the early postoperative phase after TKA. Twenty patients (n = 20) were prospectively enrolled. Two sensors were attached to the affected leg. The data were recorded from the first day after TKA until discharge. Algorithms were developed for detecting steps, range of motion, horizontal, sitting and standing postures, as well as physical therapy. The mean number of steps increased from day 1 to discharge from 117.4 (SD ± 110.5) to 858.7 (SD ± 320.1), respectively. Patients' percentage of immobilization during daytime (6 a.m. to 8 p.m.) was 91.2% on day one and still 69.9% on the last day. Patients received daily continuous passive motion therapy (CPM) for a mean of 36.4 min (SD ± 8.2). The mean angular velocity at day 1 was 12.2 degrees per second (SD ± 4.4) and increased to 28.7 (SD ± 16.4) at discharge. This study shows that IMUs monitor patients' activity postoperatively well, and a wide range of interindividual motion patterns was observed. These sensors may allow the adjustment of physical exercise programs according to the patient's individual needs.

Purpose: X-ray phase-contrast tomography (XPCT) is a non-destructive, three-dimensional imaging modality that provides higher contrast in soft tissue than absorption-based CT and allows one to cover the cytoarchitecture from the centi- and millimeter scale down to the nanoscale. To further increase contrast and resolution of XPCT, for example, in view of addressing connectivity issues in the central nervous system (CNS), metal staining is indispensable. However, currently used protocols, for example, based on osmium and/or uranium are less suited for XPCT, due to an excessive β / δ -ratio. In this work, we explore the suitability of different staining agents for XPCT. Particularly, neodymium(III)-acetate (NdAc), which has recently been proposed as a non-toxic, non-radioactive easy to use alternative contrast agent for uranyl acetate (UAc) in electron microscopy, is investigated. Due to its vertical proximity to UAc in the periodic table, similar chemical but better suited optical properties for phase contrast can be expected., Approach: Differently stained whole eye samples of wild type mouse and tissues of the CNS are embedded into EPON epoxy resin and scanned using synchrotron as well as with laboratory radiation. Phase retrieval is performed on the projection images, followed by tomographic reconstruction, which enables a quantitative analysis based on the reconstructed electron densities. Segmentation techniques and rendering software is used to visualize structures of interest in the sample., Results: We show that staining neuronal samples with NdAc enhances contrast, in particular for laboratory scans, allowing high-resolution imaging of biological soft tissue in-house. For the example of murine retina, specifically rods and cones as well as the sclera and the Ganglion cell layer seem to be targeted by the stain. A comparison of electron density by the evaluation of histograms allowed to determine quantitative measures to describe the difference between the examined stains., Conclusion: The results suggest NdAc to be an effective stain for XPCT, with a preferential binding to anionic groups, such as phosphate and carboxyl groups at cell surfaces, targeting certain layers of the retina with a stronger selectivity compared to other staining agents. Due to the advantageous X-ray optical properties, the stain seems particularly well-suited for phase contrast, with a comparably small number density and an overall superior image quality at laboratory sources., (© 2023 The Authors.)

Objectives. As the central organ of the respiratory system, the human lung is responsible for supplying oxygen to the blood, which reaches the erythrocytes by diffusion through the alveolar walls and is then distributed throughout the body. By exploiting the difference in electron density detected by a phase shift in soft tissue, high-resolution x-ray phase-contrast computed tomography (XPCT) can resolve biological structures in a sub- μ m range, shedding new light on the three-dimensional structure of the lungs, physiological functions and pathological mechanisms. Approach. This work presents both synchrotron and laboratory XPCT results of postmortem tissue from autopsies and biopsies embedded with various preparation protocols such as precision-cut lung slices, cryogenically fixed lung tissue, as well as paraffin and alcohol fixed tissue. The selection of pathological abnormalities includes channel of Lambert, bronchus-associated lymphoid tissue and alveolar capillary dysplasia with misalignment of pulmonary veins. Subsequently, quantification and visualization approaches are presented. Main results. The overall high image quality even of in-house XPCT scans for the case of FFPE biopsies can be exploited for a wide range of pulmonary pathologies and translated to dedicated and optimized instrumentation which could be operated in clinical setting. By using synchrotron radiation, contrast can be further increased to resolve sub- μ m sized features down to the sub-cellular level. The results demonstrate that a wide range of preparation protocols including sample mounting in liquids can be used. Significance. With XPCT, poorly understood 3D structures can be identified in larger volume overview and subsequently studied in more detail at higher resolution. With the full 3D structure, the respective physiological functions of airways or vascular networks, and the different pathophysiologic mechanisms can be elucidated or at least underpinned with structural data. Moreover, synchrotron data can be used to validate laboratory protocols and provide ground truth for standardizing the method., (Creative Commons Attribution license.)

Age-dependent oocyte aneuploidy, a major cause of Down syndrome, is associated with declining sister chromatid cohesion in postnatal oocytes. Here we show that cohesion in postnatal mouse oocytes is regulated by Tex19.1. We show Tex19.1-/- oocytes have defects maintaining chiasmata, missegregate their chromosomes during meiosis, and transmit aneuploidies to the next generation. Furthermore, we show that mouse Tex19.1 inhibits N-end rule protein degradation mediated by its interacting partner UBR2, and that Ubr2 itself has a previously undescribed role in negatively regulating the acetylated SMC3 subpopulation of cohesin in mitotic somatic cells. Lastly, we show that acetylated SMC3 is associated with meiotic chromosome axes in mouse oocytes, and that this population of cohesin is specifically depleted in the absence of Tex19.1. These findings indicate that Tex19.1 regulates UBR protein activity to maintain acetylated SMC3 and sister chromatid cohesion in postnatal oocytes and prevent aneuploidy from arising in the female germline., (© 2020 Reichmann et al.)

Fast-track surgery is becoming increasingly popular, whereas the monitoring of postoperative rehabilitation remains a matter of considerable debate. The aim of this study was to validate a newly developed wearable system intended to monitor knee function and mobility. A sensor system with a nine-degree-of-freedom (DOF) inertial measurement unit (IMU) was developed. Thirteen healthy volunteers performed five 10-meter walking trials with simultaneous sensor and motion capture data collection. The obtained kinematic waveforms were analysed using root mean square error (RMSE) and correlation coefficient (CC) calculations. The Bland-Altman method was used for the agreement of discrete parameters consisting of peak knee angles between systems. To test the reliability, 10 other subjects with sensors walked a track of 10 metres on two consecutive days. The Pearson CC was excellent for the walking data set between both systems (r = 0.96) and very good (r = 0.95) within the sensor system. The RMSE during walking was 5.17° between systems and 6.82° within sensor measurements. No significant differences were detected between the mean values observed, except for the extension angle during the stance phase (E1). Similar results were obtained for the repeatability test. Intra-class correlation coefficients (ICCs) between systems were excellent for the flexion angle during the swing phase (F1); good for the flexion angle during the stance phase (F2) and the re-extension angle, which was calculated by subtracting the extension angle at swing phase (E2) from F2; and moderate for the extension angle during the stance phase (E1), E2 and the range of motion (ROM). ICCs within the sensor measurements were good for the ROM, F2 and re-extension, and moderate for F1, E1 and E2. The study shows that the novel sensor system can record sagittal knee kinematics during walking in healthy subjects comparable to those of a motion capture system.

At the beginning of mammalian life, the genetic material from each parent meets when the fertilized egg divides. It was previously thought that a single microtubule spindle is responsible for spatially combining the two genomes and then segregating them to create the two-cell embryo. We used light-sheet microscopy to show that two bipolar spindles form in the zygote and then independently congress the maternal and paternal genomes. These two spindles aligned their poles before anaphase but kept the parental genomes apart during the first cleavage. This spindle assembly mechanism provides a potential rationale for erroneous divisions into more than two blastomeric nuclei observed in mammalian zygotes and reveals the mechanism behind the observation that parental genomes occupy separate nuclear compartments in the two-cell embryo., (Copyright © 2018 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works.)

Systematic studies of cell divisions at the beginning of mammalian life are of fundamental importance for our understanding of embryonic development and fertility. However, in the past the challenges of in vitro embryo culture and the embryo's pronounced light sensitivity have precluded a detailed investigation of preimplantation cell divisions. This protocol is based on recent technological breakthroughs in inverted light microscopy tailored for mouse embryology. Due to its reduced light dose, and therefore low phototoxicity, as well as higher acquisition speed, light-sheet microscopy allows extended 3D time-lapse imaging of early embryonic development with very high spatial and temporal resolution. This imaging approach enables imaging of key subcellular structures during the critical cell cycles from the zygote up to the blastocyst stage, with a resolution that allows automatic computational tracking and quantitative analysis of the dynamics of mitotic organelles., (© 2018 Elsevier Inc. All rights reserved.)

Mobilization of retrotransposons to new genomic locations is a significant driver of mammalian genome evolution, but these mutagenic events can also cause genetic disorders. In humans, retrotransposon mobilization is mediated primarily by proteins encoded by LINE-1 (L1) retrotransposons, which mobilize in pluripotent cells early in development. Here we show that TEX19.1, which is induced by developmentally programmed DNA hypomethylation, can directly interact with the L1-encoded protein L1-ORF1p, stimulate its polyubiquitylation and degradation, and restrict L1 mobilization. We also show that TEX19.1 likely acts, at least in part, through promoting the activity of the E3 ubiquitin ligase UBR2 towards L1-ORF1p. Moreover, loss of Tex19.1 increases L1-ORF1p levels and L1 mobilization in pluripotent mouse embryonic stem cells, implying that Tex19.1 prevents de novo retrotransposition in the pluripotent phase of the germline cycle. These data show that post-translational regulation of L1 retrotransposons plays a key role in maintaining trans-generational genome stability in mammals.

Despite its importance for understanding human infertility and congenital diseases, early mammalian development has remained inaccessible to in toto imaging. We developed an inverted light-sheet microscope that enabled us to image mouse embryos from zygote to blastocyst, computationally track all cells and reconstruct a complete lineage tree of mouse pre-implantation development. We used this unique data set to show that the first cell fate specification occurs at the 16-cell stage.

DNA methylation plays an important role in suppressing retrotransposon activity in mammalian genomes, yet there are stages of mammalian development where global hypomethylation puts the genome at risk of retrotransposition-mediated genetic instability. Hypomethylated primordial germ cells appear to limit this risk by expressing a cohort of retrotransposon-suppressing genome-defence genes whose silencing depends on promoter DNA methylation. Here, we investigate whether similar mechanisms operate in hypomethylated trophectoderm-derived components of the mammalian placenta to couple expression of genome-defence genes to the potential for retrotransposon activity. We show that the hypomethylated state of the mouse placenta results in activation of only one of the hypomethylation-sensitive germline genome-defence genes: Tex19.1. Tex19.1 appears to play an important role in placenta function as Tex19.1(-/-) mouse embryos exhibit intra-uterine growth retardation and have small placentas due to a reduction in the number of spongiotrophoblast, glycogen trophoblast and sinusoidal trophoblast giant cells. Furthermore, we show that retrotransposon mRNAs are derepressed in Tex19.1(-/-) placentas and that protein encoded by the LINE-1 retrotransposon is upregulated in hypomethylated trophectoderm-derived cells that normally express Tex19.1. This study suggests that post-transcriptional genome-defence mechanisms are operating in the placenta to protect the hypomethylated cells in this tissue from retrotransposons and suggests that imbalances between retrotransposon activity and genome-defence mechanisms could contribute to placenta dysfunction and disease.

Background: DNA methylation and the Polycomb repression system are epigenetic mechanisms that play important roles in maintaining transcriptional repression. Recent evidence suggests that DNA methylation can attenuate the binding of Polycomb protein components to chromatin and thus plays a role in determining their genomic targeting. However, whether this role of DNA methylation is important in the context of transcriptional regulation is unclear., Results: By genome-wide mapping of the Polycomb Repressive Complex 2-signature histone mark, H3K27me3, in severely DNA hypomethylated mouse somatic cells, we show that hypomethylation leads to widespread H3K27me3 redistribution, in a manner that reflects the local DNA methylation status in wild-type cells. Unexpectedly, we observe striking loss of H3K27me3 and Polycomb Repressive Complex 2 from Polycomb target gene promoters in DNA hypomethylated cells, including Hox gene clusters. Importantly, we show that many of these genes become ectopically expressed in DNA hypomethylated cells, consistent with loss of Polycomb-mediated repression., Conclusions: An intact DNA methylome is required for appropriate Polycomb-mediated gene repression by constraining Polycomb Repressive Complex 2 targeting. These observations identify a previously unappreciated role for DNA methylation in gene regulation and therefore influence our understanding of how this epigenetic mechanism contributes to normal development and disease.

Purpose: In this anatomical study, we compared the diagnostic accuracy of rotational panoramic radiography (OPG), computed tomography (CT) and cone beam computed tomography (CBCT) to the actual anatomical situation., Materials and Methods: Dental images were taken of 10 human cadaver heads. Thereafter, they were prepared and measured. The height of the alveolar ridge to the mandibular canal was compared with the prior images taken. The deviation from the anatomical situation was calculated for each imaging technique., Results: In the group of OPG images, there was a median of 2.3 mm distortion ranging from -0.2 to 5.7 mm in the vertical plane compared to the actual situation found during dissection. If steel balls were used during OPG, the median distortion was lowered to 0.2 mm, but the width of -1.6 to 3 mm was still quite extensive. CT images showed a mean distortion of -0.2 mm and a width of -1.5 to 1.3 mm. The mean distortion of the CBCT images was similar to the one found in CT, namely -0.3 mm with a range from -1.5 to 0.8 mm., Conclusions: The results show that OPG using steel balls as a calibration reference seems reliable in a standard situation. In more difficult cases, modern three-dimensional techniques should be used to additionally determine available bone volume.

Mouse primordial germ cells (PGCs) erase global DNA methylation (5mC) as part of the comprehensive epigenetic reprogramming that occurs during PGC development. 5mC plays an important role in maintaining stable gene silencing and repression of transposable elements (TE) but it is not clear how the extensive loss of DNA methylation impacts on gene expression and TE repression in developing PGCs. Using a novel epigenetic disruption and recovery screen and genetic analyses, we identified a core set of germline-specific genes that are dependent exclusively on promoter DNA methylation for initiation and maintenance of developmental silencing. These gene promoters appear to possess a specialised chromatin environment that does not acquire any of the repressive H3K27me3, H3K9me2, H3K9me3 or H4K20me3 histone modifications when silenced by DNA methylation. Intriguingly, this methylation-dependent subset is highly enriched in genes with roles in suppressing TE activity in germ cells. We show that the mechanism for developmental regulation of the germline genome-defence genes involves DNMT3B-dependent de novo DNA methylation. These genes are then activated by lineage-specific promoter demethylation during distinct global epigenetic reprogramming events in migratory (~E8.5) and post-migratory (E10.5-11.5) PGCs. We propose that genes involved in genome defence are developmentally regulated primarily by promoter DNA methylation as a sensory mechanism that is coupled to the potential for TE activation during global 5mC erasure, thereby acting as a failsafe to ensure TE suppression and maintain genomic integrity in the germline.

Retrotransposons are highly prevalent in mammalian genomes due to their ability to amplify in pluripotent cells or developing germ cells. Host mechanisms that silence retrotransposons in germ cells and pluripotent cells are important for limiting the accumulation of the repetitive elements in the genome during evolution. However, although silencing of selected individual retrotransposons can be relatively well-studied, many mammalian retrotransposons are seldom analysed and their silencing in germ cells, pluripotent cells or somatic cells remains poorly understood. Here we show, and experimentally verify, that cryptic repetitive element probes present in Illumina and Affymetrix gene expression microarray platforms can accurately and sensitively monitor repetitive element expression data. This computational approach to genome-wide retrotransposon expression has allowed us to identify the histone deacetylase Hdac1 as a component of the retrotransposon silencing machinery in mouse embryonic stem cells, and to determine the retrotransposon targets of Hdac1 in these cells. We also identify retrotransposons that are targets of other retrotransposon silencing mechanisms such as DNA methylation, Eset-mediated histone modification, and Ring1B/Eed-containing polycomb repressive complexes in mouse embryonic stem cells. Furthermore, our computational analysis of retrotransposon silencing suggests that multiple silencing mechanisms are independently targeted to retrotransposons in embryonic stem cells, that different genomic copies of the same retrotransposon can be differentially sensitive to these silencing mechanisms, and helps define retrotransposon sequence elements that are targeted by silencing machineries. Thus repeat annotation of gene expression microarray data suggests that a complex interplay between silencing mechanisms represses retrotransposon loci in germ cells and embryonic stem cells.

In mammals, germ cells derive from the pluripotent cells that are present early in embryogenesis, and then differentiate into male sperm or female eggs as development proceeds. Fusion between an egg and a sperm at fertilization allows genetic information from both parents to be transmitted to the next generation, and produces a pluripotent zygote to initiate the next round of embryogenesis. Meiosis is a central event in this self-perpetuating cycle that creates genetic diversity by generating new combinations of existing genetic alleles, and halves the number of chromosomes in the developing male and female germ cells to allow chromosome number to be maintained through successive generations. The developing germ cells also help to maintain genetic and chromosomal stability through the generations by protecting the genome from excessive de novo mutation. Several mouse mutants have recently been characterised whose germ cells exhibit defects in silencing the potentially mutagenic endogenous retroviruses and other retrotransposons that are prevalent in mammalian genomes, and these germ cells also exhibit defects in progression through meiosis. Here we review how mouse germ cells develop and proceed through meiosis, how mouse germ cells silence endogenous retroviruses and other retrotransposons, and discuss why silencing of endogenous retroviruses and other retrotransposons may be required for meiotic progression in mice., (Copyright 2009 International Society of Differentiation. Published by Elsevier B.V. All rights reserved.)

The epicardial epithelial-mesenchymal transition (EMT) is hypothesized to generate cardiovascular progenitor cells that differentiate into various cell types, including coronary smooth muscle and endothelial cells, perivascular and cardiac interstitial fibroblasts and cardiomyocytes. Here we show that an epicardial-specific knockout of the gene encoding Wilms' tumor-1 (Wt1) leads to a reduction in mesenchymal progenitor cells and their derivatives. We show that Wt1 is essential for repression of the epithelial phenotype in epicardial cells and during embryonic stem cell differentiation through direct transcriptional regulation of the genes encoding Snail (Snai1) and E-cadherin (Cdh1), two of the major mediators of EMT. Some mesodermal lineages do not form in Wt1-null embryoid bodies, but this effect is rescued by the expression of Snai1, underscoring the importance of EMT in generating these differentiated cells. These new insights into the molecular mechanisms regulating cardiovascular progenitor cells and EMT will shed light on the pathogenesis of heart diseases and may help the development of cell-based therapies.

Between 1975 and 1989 we carried out a total of 567 resections of the colon and rectum and performed a uni- or bilateral ovarectomy in 53 (9.3%) cases. Histopathological findings in the case of 41 (7.2%) patients were unremarkable whereas 8 cases (1.4%) revealed metastases of the colorectal cancer. In the case of 4 patients (0.7%) synchronous ovarian cancer occurred. According to the TNM-scheme primary tumors included T2 in 2 cases, T3 in 5 and T4 in 1 of the cases. Reported figures of ovarian metastases in colorectal cancer vary between 2.0 and 10.3%, we found 2.1% in our series. Prophylactic ovarectomy even in premenopausal patients is indicated if one or both ovaries show pathological findings on laparotomy since infiltrative growth of the tumor can be proved only histologically. In addition we performed bilateral oophorectomy on postmenopausal women as a method of preventing occurrence of other ovarian tumors.

We observed 17 cases of so-called recurrences of achalasia of the cardia (10 times after preceding dilatation and 7 times after Heller's operation). For surgical treatment 16 of these patients underwent cardiomyotomy, using the transthoracic approach. In one patient who had cardiomyotomy plus fundoplication at the first operation an oesophago-gastrostomy became necessary. Three quarter of these patients had a satisfactory result when followed up. I case of recurrence the authors recommend to give priority to cardiomyotomy, rather than to dilatation or bougienage.