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Much of what we know about the early stages of T cell activation has been obtained from studies of T cells interacting with glass-supported lipid bilayers that favor imaging but are orders of magnitude stiffer than typical cells. We developed a method for attaching lipid bilayers to polydimethylsiloxane polymer supports, producing “soft bilayers” with physiological levels of mechanical resistance (Young’s modulus of 4 kPa). Comparisons of T cell behavior on soft and glass-supported bilayers revealed that whereas late stages of T cell activation are thought to be substrate-stiffness dependent, early calcium signaling was unaffected by substrate rigidity, implying that early steps in T cell receptor triggering are not mechanosensitive. The exclusion of large receptor-type phosphatases was observed on the soft bilayers, however, even though it is yet to be demonstrated at authentic cell-cell contacts. This work sets the stage for an imaging-based exploration of receptor signaling under conditions closely mimicking physiological cell-cell contact.

In development, lineage segregation of multiple lineages must be coordinated in time and space. An important example is the mammalian inner cell mass (ICM), in which the primitive endoderm (PrE, founder of the yolk sac) physically segregates from the epiblast (EPI, founder of the foetus). The physical mechanisms that determine this spatial segregation between EPI and PrE are still poorly understood. Here, we identify an asymmetry in cell-cell affinity, a mechanical property thought to play a significant role in tissue sorting in other systems, between EPI and PrE precursors (pEPI and pPrE). However, a computational model of cell sorting indicated that these differences alone appeared insufficient to explain the spatial segregation. We also observed significantly greater surface fluctuations in pPrE compared to pEPI. Including the enhanced surface fluctuation in pPrE in our simulation led to robust cell sorting. We identify phospho-ERM regulated membrane tension as an important mediator of the increased surface fluctuations in pPrE. Using aggregates of engineered cell lines with different surface fluctuation levels cells with higher surface fluctuations were consistently excluded to the outside of the aggregate. These cells behaved similarly when incorporated in the embryo. Surface fluctuations-driven segregation is reminiscent of activity-induced phase separation, a sorting phenomenon in colloidal physics. Together, our experiments and model identify dynamic cell surface fluctuations, in addition to static mechanical properties, as a key factor for orchestrating the correct spatial positioning of the founder embryonic lineages.

Background and aims: In patients with hepatocellular carcinoma (HCC), macrovascular invasion (MaVI) limits treatment options and decreases survival. Detailed data on the relationship between MaVI extension and patients' characteristics, and its impact on patients' outcome are limited. We evaluated the prevalence and extension of MaVI in a large cohort of consecutive HCC patients, analysing its association with liver disease and tumour characteristics, as well as with treatments performed and patients' survival. Methods: We analysed data of 4774 patients diagnosed with HCC recorded in the Italian Liver Cancer (ITA.LI.CA) database (2008-2018). Recursive partition analysis (RPA) was performed to evaluate interactions between MaVI, clinical variables and treatment, exploring the inter-relationship determining overall survival. Results: MaVI prevalence was 11.1%, and median survival of these patients was 6.0months (95% CI, 5.1-7.1). MaVI was associated with younger age at diagnosis, presence of symptoms, worse Performance Status (PS) and liver function, high alphafetoprotein levels and large HCCs. MaVI extension was associated with worse PS, ascites and greater impairment in liver function. RPA identified patients' categories with different treatment indications and survival, ranging from 2.4months in those with PS>1 and ascites, regardless of MaVI extension (receiving best supportive care in 90.3% of cases), to 14.1months in patients with PS 0-1, no ascites and Vp1-Vp2 MaVI (treated with surgery in 19.1% of cases). Conclusions: MaVI presence and extension, together with PS and ascites, significantly affect patients' survival and treatment selection. The decision tree based on these parameters may help assess patients' prognosis and inform therapeutic decisions.

HINTERGRUND: Personen mit Migrationshintergrund (PmM) unterscheiden sich als Bevölkerungsgruppe hinsichtlich Morbidität, Mortalität und Inanspruchnahme des Gesundheitssystems meist von der autochthonen Bevölkerung, sie nehmen jedoch seltener an Gesundheitsstudien teil. Die Gruppe der PmM ist sehr heterogen, was in Studien bisher kaum berücksichtigt wird. ZIEL DER ARBEIT: Es werden soziodemografische Charakteristika der PmM in der NAKO Gesundheitsstudie (Alter, Geschlecht, Zeit seit Migration, Bildung) dargestellt. Zudem wird exemplarisch untersucht, ob der Migrationshintergrund mit der Nutzung des Angebots zur Früherkennung von Darmkrebs (Hämoccult-Test) zusammenhängt. METHODEN: Daten der ersten 101.816 Teilnehmenden der NAKO wurden deskriptiv und kartografisch ausgewertet. Die Zuweisung des Migrationshintergrunds erfolgte anhand der Definition des Statistischen Bundesamts und basiert auf Staatsangehörigkeit, Geburtsland, Einreisejahr und Geburtsland der Eltern. ERGEBNISSE: Der Anteil der PmM liegt bei 16,0 %. Die Verteilung über die 18 Studienzentren variiert zwischen 6 % (Neubrandenburg) und 33 % (Düsseldorf). Mit 153 Herkunftsländern sind in der NAKO die meisten Länder vertreten. Bei allen Variablen zeigen sich deutliche Unterschiede zwischen den verschiedenen Herkunftsregionen. Am Hämoccult-Test nehmen türkeistämmige Personen (OR = 0,67) und Aussiedler aus der ehemaligen Sowjetunion (OR = 0,60) seltener teil. PmM, die in Deutschland geboren sind, unterscheiden sich diesbezüglich nicht von der autochthonen Bevölkerung (OR = 0,99). DISKUSSION: PmM in der NAKO sind eine sehr heterogene Gruppe. Jedoch lassen sich aufgrund der Stichprobengröße einzelne Untergruppen der PmM hinsichtlich ihrer Herkunftsregion separat untersuchen. BACKGROUND: Persons with a migration background (PmM) as a population group usually differ from the autochthonous population in terms of morbidity, mortality, and use of the health care system, but they participate less frequently in health studies. The PmM group is very heterogeneous, which has hardly been taken into account in studies so far. OBJEKTIVES: Sociodemographic characteristics of PmM in the NAKO health study (age, sex, time since migration, education) are presented. In addition, it is examined through an example whether migration background is related to the use of cancer screening for colorectal cancer (hemoccult test). METHODS: Data of the first 101,816 persons of the NAKO were analyzed descriptively and cartographically. The migration background was assigned on the basis of the definition of the Federal Statistical Office, based on nationality, country of birth, year of entry, and country of birth of the parents. RESULTS: Overall, the PmM proportion is 16.0%. The distribution across the 18 study centers varies considerably between 6% (Neubrandenburg) and 33% (Düsseldorf). With 153 countries of origin, most countries are represented in the NAKO. All variables show clear differences between the different regions of origin. In the hemoccult test, persons of Turkish origin (OR = 0.67) and resettlers (OR = 0.60) have a lower participation rate. PmM born in Germany do not differ in this respect from the autochthonous population (OR = 0.99). CONCLUSION: PmM in the NAKO are a very heterogeneous group. However, due to the sample size, individual subgroups of migrants can be studied separately with respect to region of origin.

Evaluation of expression profile in autism spectrum disorder (ASD) patients is an important approach to understand possible similar functional consequences that may underlie disease pathophysiology regardless of its genetic heterogeneity. Induced pluripotent stem cell (iPSC)-derived neuronal models have been useful to explore this question, but larger cohorts and different ASD endophenotypes still need to be investigated. Moreover, whether changes seen in this in vitro model reflect previous findings in ASD postmortem brains and how consistent they are across the studies remain underexplored questions. We examined the transcriptome of iPSC-derived neuronal cells from a normocephalic ASD cohort composed mostly of high-functioning individuals and from non-ASD individuals. ASD patients presented expression dysregulation of a module of co-expressed genes involved in protein synthesis in neuronal progenitor cells (NPC), and a module of genes related to synapse/neurotransmission and a module related to translation in neurons. Proteomic analysis in NPC revealed potential molecular links between the modules dysregulated in NPC and in neurons. Remarkably, the comparison of our results to a series of transcriptome studies revealed that the module related to synapse has been consistently found as upregulated in iPSC-derived neurons—which has an expression profile more closely related to fetal brain—while downregulated in postmortem brain tissue, indicating a reliable association of this network to the disease and suggesting that its dysregulation might occur in different directions across development in ASD individuals. Therefore, the expression pattern of this network might be used as biomarker for ASD and should be experimentally explored as a therapeutic target.

Most animal cells are surrounded by a cell membrane and an underlying actomyosin cortex. Both structures are linked with each other, and they are under tension. Membrane tension and cortical tension both influence many cellular processes, including cell migration, division, and endocytosis. However, while actomyosin tension is regulated by substrate stiffness, how membrane tension responds to mechanical substrate properties is currently poorly understood. Here, we probed the effective membrane tension of neurons and fibroblasts cultured on glass and polyacrylamide substrates of varying stiffness using optical tweezers. In contrast to actomyosin-based traction forces, both peak forces and steady state tether forces of cells cultured on hydrogels were independent of substrate stiffness and did not change after blocking myosin II activity using blebbistatin, indicating that tether and traction forces are not directly linked with each other. Peak forces on hydrogels were about twice as high in fibroblasts if compared to neurons, indicating stronger membrane-cortex adhesion in fibroblasts. Finally, tether forces were generally higher in cells cultured on hydrogels compared to cells cultured on glass, which we attribute to substrate-dependent alterations of the actomyosin cortex and an inverse relationship between tension along stress fibres and cortical tension. Our results provide new insights into the complex regulation of membrane tension, and they pave the way for a deeper understanding of biological processes instructed by it.

During the development of the nervous system, neurons extend bundles of axons that grow and meet other neurons to form the neuronal network. Robust guidance mechanisms are needed for these bundles to migrate and reach their functional target. Directional information depends on external cues such as chemical or mechanical gradients. Unlike chemotaxis that has been extensively studied, the role and mechanism of durotaxis, the directed response to variations in substrate rigidity, remain unclear. We model bundle migration and guidance by rigidity gradients by using the theory of morphoelastic rods. We show that, at a rigidity interface, the motion of axon bundles follows a simple behavior analogous to optic ray theory and obeys Snell's law for refraction and reflection. We use this powerful analogy to demonstrate that axons can be guided by the equivalent of optical lenses and fibers created by regions of different stiffnesses.

BackgroundGlioblastoma (GBM) is a highly aggressive incurable brain tumor. The main cause of mortality in GBM patients is the invasive rim of cells migrating away from the main tumor mass and invading healthy parts of the brain. Although motion is driven by forces, our current understanding of the physical factors involved in glioma infiltration remains limited. This study aims to investigate the adhesion properties within and between patients’ tumors on a cellular level and test whether these properties correlate with cell migration.MethodsNine tissue samples were taken from spatially separated sections during 5-aminolevulinic acid (5-ALA) fluorescence guided surgery. Navigated biopsy samples were collected from strongly fluorescent tumor cores, a weak fluorescent tumor rim, and non-fluorescent tumor margins. A microfluidics device was built to induce controlled shear forces to detach cells from monolayer cultures. Cells were cultured on low modulus polydimethylsiloxane representative of the stiffness of brain tissue. Cell migration and morphology were then obtained using time lapse microscopy.ResultsGBM cell populations from different tumor fractions of the same patient exhibited different migratory and adhesive behaviors. These differences were associated with sampling location and amount of 5-ALA fluorescence. Cells derived from weak- and non-fluorescent tumor tissue were smaller, adhered less well, and migrated quicker than cells derived from strongly fluorescent tumor mass.ConclusionGBM tumors are biomechanically heterogeneous. Selecting multiple populations and broad location sampling are therefore important to consider for drug testing.Key pointsGBM tumors are biomechanically heterogeneousGBM cell migration is inversely correlated with cell-matrix adhesion strength5-ALA fluorescence intensity during surgery correlates with the motility properties of GBM cellsImportance of the studyThis is the first study to compare single cell migration and cell-matrix adhesion strength of GBM, using cell lines derived from different tumors and from different regions within the same tumor. Not accounting for internal sampling location within each tumor obscures differences in cell morphology, motility and adhesion properties between patients. Peripherical and marginal tumor cells have different adhesion profiles and are highly migratory compared to those found in the core of the tumor. Aggressive regions of the tumor (highly motile) are linked to the spatial distribution of adhesion strength and are strongly associated with 5-ALA fluorescence intensity. Preclinical tests aimed at developing a treatment for GBM using anti-invasive drugs or adhesion inhibitors, would benefit from using cell lines derived from the tumor periphery (with low 5-ALA intensity) rather than cell lines derived from the tumor core.

Funding: We acknowledge funding from the German Science Foundation (DFG grant numbers RH 147/1-1 to J.R., EXC 1003 CiM to T.B.), the Herchel Smith Foundation (postdoctoral fellowship to A.D.), the Royal Society (University Research Fellowship to K.J.C.), the UK EPSRC (programme grant number EP/P030017/1 to M.C.G.), the Human Frontier Science Program (HFSP grant number RGP0018/2017 to T.B.), the European Research Council (consolidator grant numbers 772798 to K.J.C., 771201 to T.B., 647186 to G.C. and 772426 to K.F.), and the UK BBSRC (equipment grant number BB/R000042/1 to G.C. and research project grant number BB/N006402/1 to K.F.). Cortical stiffness is an important cellular property that changes during migration, adhesion and growth. Previous atomic force microscopy (AFM) indentation measurements of cells cultured on deformable substrates have suggested that cells adapt their stiffness to that of their surroundings. Here we show that the force applied by AFM to a cell results in a significant deformation of the underlying substrate if this substrate is softer than the cell. This ‘soft substrate effect’ leads to an underestimation of a cell’s elastic modulus when analysing data using a standard Hertz model, as confirmed by finite element modelling and AFM measurements of calibrated polyacrylamide beads, microglial cells and fibroblasts. To account for this substrate deformation, we developed a ‘composite cell–substrate model’. Correcting for the substrate indentation revealed that cortical cell stiffness is largely independent of substrate mechanics, which has major implications for our interpretation of many physiological and pathological processes. Postprint

Cell-cell contacts often underpin signaling between cells. For immunology, the binding of a T cell receptor to an antigen-presenting pMHC initiates downstream signaling and an immune response. Although this contact is mediated by proteins on both cells creating interfaces with gap sizes typically around 14 nm, many, often contradictory observations have been made regarding the influence of the contact on parameters such as the binding kinetics, spatial distribution, and diffusion of signaling proteins within the contact. Understanding the basic physical constraints on probes inside this crowded environment will help inform studies on binding kinetics and dynamics of signaling of relevant proteins in the synapse. By tracking quantum dots of different dimensions for extended periods of time, we have shown that it is possible to obtain the probability of a molecule entering the contact, the change in its diffusion upon entry, and the impact of spatial heterogeneity of adhesion protein density in the contact. By analyzing the contacts formed by a T cell interacting with adhesion proteins anchored to a supported lipid bilayer, we find that probes are excluded from contact entry in a size-dependent manner for gap-to-probe differences of 4.1 nm. We also observed probes being trapped inside the contact and a decrease in diffusion of up to 85% in dense adhesion protein contacts. This approach provides new, to our knowledge, insights into the nature of cell-cell contacts, revealing that cell contacts are highly heterogeneous because of topography- and protein-density-related processes. These effects are likely to profoundly influence signaling between cells.

Single-cell genomics provides unprecedented potential for research on plant development and environmental responses. Here, we introduce a generic procedure for plant nucleus isolation combined with nanowell-based library preparation. Our method enables the transcriptome analysis of thousands of individual plant nuclei. It serves as an alternative to the use of protoplast isolation, which is currently a standard methodology for plant single-cell genomics, although it can be challenging for some plant tissues. We show the applicability of our nucleus isolation method by using different plant materials from different species. The potential of our single-nucleus RNA sequencing method is shown through the characterization of transcriptomes of seedlings and developing flowers from Arabidopsis thaliana. We evaluated the transcriptome dynamics during the early stages of anther development, identified stage-specific activities of transcription factors regulating this process, and predicted potential target genes of these transcription factors. Our nucleus isolation procedure can be applied in different plant species and tissues, thus expanding the toolkit for plant single-cell genomics experiments.

Luminescent semiconductor quantum dots (QDs) have recently been suggested as novel probes for imaging and sensing cell membrane voltages. However, a key bottleneck for their development is a lack of techniques to assess QD responses to voltages generated in the aqueous electrolytic environments typical of biological systems. Even more generally, there have been relatively few efforts to assess the response of QDs to voltage changes in live cells. Here, we develop a platform for monitoring the photoluminescence (PL) response of QDs under AC and DC voltage changes within aqueous ionic environments. We evaluate both traditional CdSe/CdS and more biologically compatible InP/ZnS QDs at a range of ion concentrations to establish their PL/voltage characteristics on chip. Wide-field, few-particle PL measurements with neuronal cells show the QDs can be used to track local voltage changes with greater sensitivity (ΔPL up to twice as large) than state-of-the-art calcium imaging dyes, making them particularly appealing for tracking subthreshold events. Additional physiological observation studies showed that while CdSe/CdS dots have greater PL responses on membrane depolarization, their lower cytotoxicity makes InP/ZnS far more suitable for voltage sensing in living systems. Our results provide a methodology for the rational development of QD voltage sensors and highlight their potential for imaging changes in cell membrane voltage.

Background The prevalence of visual impairment and of impaired functional reading ability rapidly increase with age. However, functional reading ability is essential for an autonomous lifestyle. We analyzed the prevalence of impaired functional reading ability in the general elderly population and the association of impaired functional reading ability with quality of life, daily activities, mobility, and social participation. Methods Cross-sectional data from a population-based cohort were analyzed. Participants aged ≥65 years were tested for their functional reading ability using (1) Nieden charts (cognitive reading ability) and (2) a test in which a telephone number had to be found (reading comprehension). Prevalences of impaired functional reading ability were calculated. In multivariable regression models, the associations of cognitive reading ability (1) with quality of life, daily activities, mobility, and social participation were examined. Results 60 of 780 participants (7.69%) were able to read the third last text of the Nieden test (good cognitive reading ability), whereas 7 participants (0.9%) were unable to read any of the texts. 716 participants (91.8%) identified the phone book entry successfully (good reading comprehension). Multivariable regression models revealed no significant associations of the cognitive reading ability (1) with quality of life, daily activities, social participation, and mobility. Conclusion Our results showed a high prevalence of impaired cognitive reading ability (1). Reading comprehension (2) was slightly affected. The loss of cognitive reading ability usually progresses over years; signs and symptoms might remain unrecognized when compensated by other functions.

SummaryIn many eukaryotic cells, directed molecular transport occurs along microtubules. Within neuronal axons, transport over vast distances particularly relies on uniformly oriented microtubules, whose +-ends point towards the distal axon tip (+end out). However, axonal microtubules initially have mixed orientations, and how they orient during development is not yet fully understood. Using live imaging of primary Drosophila melanogaster neurons and physical modelling, we found that +end out microtubules are less likely to undergo catastrophe near the advancing axon tip, leading to their persistent long-term growth. In contrast, oppositely oriented microtubules remain short. Using chemical and physical perturbations of microtubule growth and genetic perturbations of the anti -catastrophe factor p150, which was enriched in the distal axon tip, we confirmed that the enhanced growth of +end out microtubules is critical for achieving uniform microtubule orientation. Computer simulations of axon development mimicking the enhanced +end out microtubule growth identified here along with previously proposed mechanisms correctly predicted the long-term evolution of axonal microtubule orientation as found in our experiments, highlighting the importance of the reduced catastrophe rate of +end out microtubules near the advancing axon tip in establishing uniform microtubule polarity. Our study thus leads to a holistic explanation of how axonal microtubules orient uniformly, a prerequisite for efficient long-range transport essential for neuronal functioning.

To this day, epidemics pose a considerable threat to mankind. Experimental models that simulate the spread of infectious diseases are thus crucial to the inception of effective control policies. Current models have had great success incorporating virulence and host immune response but do rarely take host genetics, behavior and host environment into account. Here, we present a full-scale imaging setup that utilizes the infection of the nematode C. elegans with a positive-stranded RNA virus (Orsay Virus) to probe key epidemiological parameters and simulate the spread of infection in a whole population. We demonstrate that our system is able to quantify infection levels and host behavior at a high sampling rate and show that different host genetic backgrounds can influence viral spread, while also highlighting the influence of infection on various host behaviors. Future work will allow the isolation of key behavioral and environmental factors that affect viral spread, potentially enabling novel policies to combat the spread of viral infections.Significance StatementIn the ongoing COVID-19 pandemic, we struggle to find effective control policies that “stop the spread”. While current animal models of virus spread in populations are highly sophisticated, they rarely explore effects of host behavior and its environment. We developed an experimental animal model system that allows us to visualize virus transmission in whole populations of C. elegans while also measuring behaviors. We were able to demonstrate how C. elegans genetics influences the progression of viral infection in a population and how animals adjust their behavior when infected. In the future, we envision that animal model systems like ours are used to test the effects of viral control policies on viral spread before they are applied in real world scenarios.

Kymographs are graphical representations of spatial position over time, which are often used in biology to visualise the motion of fluorescent particles, molecules, vesicles, or organelles moving along a predictable path. Although in kymographs tracks of individual particles are qualitatively easily distinguished, their automated quantitative analysis is much more challenging. Kymographs often exhibit low signal-to-noise-ratios (SNRs), and available tools that automate their analysis usually require manual supervision. Here we developed KymoButler, a Deep Learning-based software to automatically track dynamic processes in kymographs. We demonstrate that KymoButler performs as well as expert manual data analysis on kymographs with complex particle trajectories from a variety of different biological systems. The software was packaged in a web-based ‘one-click’ application for use by the wider scientific community (http://kymobutler.deepmirror.ai). Our approach significantly speeds up data analysis, avoids unconscious bias, and represents another step towards the widespread adaptation of Machine Learning techniques in biological data analysis., eLife digest Many molecules and structures within cells have to move about to do their job. Studying these movements is important to understand many biological processes, including the development of the brain or the spread of viruses. Kymographs are images that represent the movement of particles in time and space. Unfortunately, tracing the lines that represent movement in kymographs of biological particles is hard to do automatically, so currently this analysis is done by hand. Manually annotating kymographs is tedious, time-consuming and prone to the researcher’s unconscious bias. In an effort to simplify the analysis of kymographs, Jakobs et al. have developed KymoButler, a software tool that can do it automatically. KymoButler uses artificial intelligence to trace the lines in a kymograph and extract the information about particle movement. It speeds up analysis of kymographs by between 50 and 250 times, and comparisons show that it is as reliable as manual analysis. KymoButler is also significantly more effective than any previously existing automatic kymograph analysis programme. To make KymoButler accessible, Jakobs et al. have also created a website with a drag-and-drop facility that allows researchers to easily use the tool. KymoButler has been tested in many areas of biological research, from quantifying the movement of molecules in neurons to analysing the dynamics of the scaffolds that help cells keep their shape. This variety of applications showcases KymoButler’s versatility, and its potential applications. Jakobs et al. are further contributing to the field of machine learning in biology with ‘deepmirror.ai’, an online hub with the goal of accelerating the adoption of artificial intelligence in biology.

During the development of the nervous system, neurons extend bundles of axons that grow and meet other neurons to form the neuronal network. Robust guidance mechanisms are needed for these bundles to migrate and reach their functional target. Directional information depends on external cues such as chemical or mechanical gradients. Unlike chemotaxis that has been extensively studied, the role and mechanism of durotaxis, the directed response to variations in substrate rigidity, remain unclear. We model bundle migration and guidance by rigidity gradients by using the theory of morphoelastic rods. We show that at a rigidity interface, the motion of axon bundles follows a simple behavior analogous to optic ray theory and obeys Snell’s law for refraction and reflection. We use this powerful analogy to demonstrate that axons can be guided by the equivalent of optical lenses and fibers created by regions of different stiffnesses.

Background Social skills are valid predictors for school readiness and subsequent school success. The federal state law for child day-care and preschools in Mecklenburg-Western Pomerania, a federal state in Germany, provides additional funds for the targeted and individualized promotion of social developmental delays for children in preschools in social hotspots. The law grants additional funds to eligible preschools, provided that each child’s development is documented with a standardized, objective and valid screening instrument. Methods To monitor the development and to detect social developmental delays, the preschools involved use the “Dortmund Developmental Screening for Preschools” (DESK 3–6). For the prevalence and risk factors, data of 5595 children aged 3 to 6 years from these preschools were analyzed. Results 9.6% of the children show reasonable findings in their social development; for a further 6.1% the results were inconclusive. Sex, presence of chronic diseases or disabilities and reasonable findings in the domains motor development and language and cognition were risk factors in terms of social development across all age groups. Conclusions The federal state law is a good example for the implementation of a standardized monitoring of the development of children. With the help of this screening instrument, prevention activities to reduce the prevalence of developmental delays can be conducted in early childhood. Early preventive activities should take into account the reported risk factors for the social development. Trial registration German Clinical Trials Register, ID: DRKS00015134, Registered on 29 October 2018, retrospectively registered.

HINTERGRUND: Muskuloskelettale Symptome und Erkrankungen sind in der Bevölkerung sehr weit verbreitet und verursachen hohe Kosten in Gesundheitswesen und Volkswirtschaft. ZIEL DER ARBEIT: Die Häufigkeit muskuloskelettaler Symptome und Erkrankungen aus den Bereichen Rückenschmerzen, Osteoporose, Arthrose und Arthritis wurde auf Basis von Daten der bevölkerungsbasierten NAKO Gesundheitsstudie beschrieben. MATERIAL UND METHODEN: Die Daten wurden in der ersten Hälfte der NAKO-Basiserhebung von März 2014 bis März 2017 bei Erwachsenen im Alter von 20–75 Jahren erhoben. In die Analysen gingen Daten von 101.779 Interviewteilnehmenden sowie von 9370 Teilnehmenden aus zwei klinischen Untersuchungen ein. Mittels der klinischen Handuntersuchung wurden tastbar geschwollene Gelenke sowie auf Druck schmerzhafte Gelenke identifiziert. Die Winkelstuhluntersuchung lieferte Daten zu Ruheschmerzen am Knie- und Hüftgelenk. Häufigkeiten wurden auf die deutsche Standardbevölkerung 2011 gewichtet. ERGEBNISSE: In den Selbstberichten der Teilnehmenden im Interview wurden am häufigsten jemals diagnostizierte andauernde Rückenschmerzen (22,5 %) und Arthrosen (20,6 %) angegeben, seltener Osteoporose (2,9 %) und rheumatoide Arthritis (1,9 %). In der Handuntersuchung wurden bei 6,0 % Schmerzen an mindestens einem Fingergelenk festgestellt. Laut Winkelstuhluntersuchung waren 8,2 % von einem Ruheschmerz in mindestens einem Knie betroffen sowie 5,1 % an der Hüfte. Frauen berichteten insgesamt häufiger muskuloskelettale Erkrankungen und Symptome als Männer, der Anteil Betroffener nahm mit dem Alter deutlich zu. DISKUSSION: Die Ergebnisse belegen die große Verbreitung vieler muskuloskelettaler Erkrankungen. Die berichtete Beschwerdelast ist mit Ergebnissen aus früheren bevölkerungsbezogenen Erhebungen vergleichbar. BACKGROUND: Musculoskeletal diseases and symptoms are very common in the general population. They lead to high healthcare costs and pose a significant burden to the national economy. OBJECTIVES: Based on data from the population-based German National Cohort (GNC), frequencies of musculoskeletal symptoms and diseases are reported, including back pain, osteoporosis, osteoarthritis, and arthritis. MATERIAL AND METHODS: Data were collected from March 2014 to March 2017 in adults aged 20–75 years during the first half of the baseline survey of the GNC. The sample comprised 101,779 interviewed subjects, including 9370 subjects who underwent clinical musculoskeletal examinations. The interview included questions about specific musculoskeletal disorders. A clinical examination of the hand provided information about palpable swollen joints and pressure-sensitive joints. Resting pain of the knees and hips was also assessed by a clinical examination. Frequencies were standardized to the German standard population of the year 2011. RESULTS: Having ever been diagnosed with recurrent back pain (22.5%) or osteoarthritis (20.6%) were the most common complaints reported in the interview; osteoporosis (2.9%) and rheumatoid arthritis (1.9%) were stated more seldom. According to the hand examination, 6.0% of all participants experienced pain in at least one finger joint. Resting pain was present in at least one knee among 8.2% and in at least one hip among 5.1% of the participants as assessed during the clinical examination. Women were more likely to report musculoskeletal disorders and symptoms than men. The proportion of adults affected by musculoskeletal diseases increased strongly with age. CONCLUSION: Musculoskeletal disorders and symptoms occur frequently. The burden of complaints and diagnoses is comparable to previous population-based surveys.

BACKGROUND: The German National Cohort (NAKO) is an interdisciplinary health study aimed at elucidating causes for common chronic diseases and detecting their preclinical stages. This article provides an overview of design, methods, participation in the examinations, and their quality assurance based on the midterm baseline dataset (MBD) of the recruitment. METHODS: More than 200,000 women and men aged 20–69 years derived from random samples of the German general population were recruited in 18 study centers (2014–2019). The data collection comprised physical examinations, standardized interviews and questionnaires, and the collection of biomedical samples for all participants (level 1). At least 20% of all participants received additional in-depth examinations (level 2), and 30,000 received whole-body magnet resonance imaging (MRI). Additional information will be collected through secondary data sources such as medical registries, health insurances, and pension funds. This overview is based on the MBD, which included 101,839 participants, of whom 11,371 received an MRI. RESULTS: The mean response proportion was 18%. The participation in the examinations was high with most of the modules performed by over 95%. Among MRI participants, 96% completed all 12 MRI sequences. More than 90% of the participants agreed to the use of complementary secondary and registry data. DISCUSSION: Individuals selected for the NAKO were willing to participate in all examinations despite the time-consuming program. The NAKO provides a central resource for population-based epidemiologic research and will contribute to developing innovative strategies for prevention, screening and prediction of chronic diseases. HINTERGRUND: Die NAKO Gesundheitsstudie ist ein bundesweites interdisziplinäres Forschungsvorhaben mit dem Ziel, die Ursachen für chronische Krankheiten und deren vorklinische Stadien zu untersuchen. Der Artikel gibt einen Überblick über das Studiendesign, die Methoden, die Teilnahme an den Untersuchungen und ihre Qualitätssicherung zur Halbzeit der Basiserhebung. METHODEN: Für die Basiserhebung wurden mehr als 200.000 Frauen und Männer im Alter von 20–69 Jahren aus Zufallsstichproben der Allgemeinbevölkerung in 18 Studienzentren rekrutiert (2014–2019). Die Basiserhebung beinhaltet Untersuchungen, Befragungen und Biomaterialien für alle Teilnehmerinnen und Teilnehmer (Level 1), ein erweitertes Programm für mindestens 20 % (Level 2) und eine Magnetresonanztomografie (MRT) für 30.000 Teilnehmerinnen und Teilnehmer. Sekundär- und Registerdaten werden über Krankheitsregister, Kranken- und Rentenversicherungen erhoben. Die Auswertung bezieht die Datenbasis zur Halbzeit der Basiserhebung mit 101.839 Teilnehmerinnen und Teilnehmern ein, davon 11.371 mit einer MRT-Untersuchung. ERGEBNISSE: Die mittlere Responsequote zur Halbzeit betrug insgesamt 18 %. Die Teilnahme an den Untersuchungen lag überwiegend bei mehr als 95 %. Bei 96 % der MRT-Teilnehmerinnen und Teilnehmer konnten alle 12 MRT-Sequenzen vollständig durchgeführt werden. Der Erschließung und wissenschaftlichen Nutzung ergänzender Sekundär- und Registerdaten stimmten mehr als 90 % der Teilnehmerinnen und Teilnehmer zu. DISKUSSION: Die Bereitschaft, möglichst alle Untersuchungsmodule durchzuführen, war trotz des zeitlichen Aufwandes außerordentlich hoch. Dadurch wird die NAKO zu einer zentralen Ressource für die epidemiologische Forschung in Deutschland. Sie wird es ermöglichen, neue Strategien zur Früherkennung, Vorhersage und Primärprävention chronischer Krankheiten zu entwickeln.

BACKGROUND: Caries and periodontitis are highly prevalent worldwide. Because detailed data on these oral diseases were collected within the framework of the German National Cohort (GNC), associations between oral and systemic diseases and conditions can be investigated. OBJECTIVES: The study protocol for the oral examination was designed to ensure a comprehensive collection of dental findings by trained non-dental staff within a limited examination time. At the mid-term of the GNC baseline examination, a first quality evaluation was performed to check the plausibility of results and to propose measures to improve the data quality. MATERIALS AND METHODS: A dental interview, saliva sampling and oral diagnostics were conducted. As part of the level‑1 examination, the number of teeth and prostheses were recorded. As part of the level‑2 examination, detailed periodontal, cariological and functional aspects were examined. All examinations were conducted by trained non-dental personnel. Parameters were checked for plausibility and variable distributions were descriptively analysed. RESULTS: Analyses included data of 57,967 interview participants, 56,913 level‑1 participants and 6295 level‑2 participants. Percentages of missing values for individual clinical parameters assessed in level 1 and level 2 ranged between 0.02 and 3.9%. Results showed a plausible distribution of the data; rarely, implausible values were observed, e.g. for measurements of horizontal and vertical overbite (overjet and overbite). Intra-class correlation coefficients indicated differences in individual parameters between regional clusters, study centres and across different examiners. CONCLUSIONS: The results confirm the feasibility of the study protocol by non-dental personnel and its successful integration into the GNC’s overall assessment program. However, rigorous dental support of the study centres is required for quality management. HINTERGRUND:Karies und Parodontitis sind weltweit hoch prävalente Erkrankungen. Durch ihre Erfassung im Rahmen der NAKO Gesundheitsstudie können Assoziationen zwischen oralen und systemischen Erkrankungen untersucht werden. FRAGESTELLUNG: In einer ersten Qualitätsanalyse zur Halbzeit der NAKO-Basiserhebung wird die Plausibilität der zahnmedizinischen Ergebnisse überprüft. Es werden Maßnahmen zur Verbesserung der Datenqualität vorgeschlagen. MATERIAL UND METHODEN: Ein zahnmedizinisches Interview, eine Speichelprobengewinnung und eine Befunderhebung wurden durchgeführt. Im Rahmen der Level-1-Untersuchung wurden Zahn- und Prothesenanzahl erfasst. In der Level-2-Untersuchung wurden detaillierte parodontologische, kariologische und funktionelle Befunde erhoben. Alle Untersuchungen wurden von geschultem nichtzahnmedizinischen Personal durchgeführt. Es wurden Plausibilitätsprüfungen durchgeführt sowie Verteilungen deskriptiv dargestellt. ERGEBNISSE: In die Analysen gingen Daten von 57.967 Interviewteilnehmer*innen, 56.913 Level-1- und 6295 Level-2-Teilnehmer*innen ein. Der Anteil fehlender Werte lag für die einzelnen Parameter der Level-1- und Level-2-Untersuchungen zwischen 0,02 % und 3,9 %. Die Parameter zeigten eine plausible Verteilung; vereinzelt wurden unplausible Werte beobachtet, z. B. beim horizontalen und vertikalen Überbiss (Overjet und Overbite). Anhand der Intraklassenkorrelationskoeffizienten wurden für die einzelnen Parameter Unterschiede zwischen regionalen Clustern, den Studienzentren und verschiedenen Untersucher*innen nachgewiesen. DISKUSSION: Die bisherigen Ergebnisse bestätigten die Umsetzbarkeit des Studienprotokolls durch nichtzahnmedizinisches Personal und die erfolgreiche Integration in das Untersuchungsprogramm der NAKO Gesundheitsstudie. Die Studienzentren benötigen eine intensive zahnmedizinische Betreuung für das Qualitätsmanagement.

BACKGROUND: Infectious diseases continue to play an important role for disease perception, health-economic considerations and public health in Germany. In recent years, infectious diseases have been linked to the development of non-communicable diseases. Analyses of the German National Cohort (GNC) may provide deeper insights into this issue and pave the way for new targeted approaches in disease prevention. OBJECTIVES: The aim was to describe the tools used to assess infectious diseases and to present initial data on infectious disease frequencies, as well as to relate the GNC assessment tools to data collection methods in other studies in Germany. METHODS: As part of the baseline examination, questions regarding infectious diseases were administered using both an interview and a self-administered touchscreen questionnaire. Data from the initial 101,787 GNC participants were analysed. RESULTS: In the interview, 0.2% (HIV/AIDS) to 8.6% (shingles) of respondents reported ever having a medical diagnosis of shingles, postherpetic neuralgia (in cases where shingles was reported), hepatitis B/C, HIV/AIDS, tuberculosis or sepsis if treated in hospital. In the questionnaire, 12% (cystitis) to 81% (upper respiratory tract infections) of respondents reported having experienced at least one occurrence of upper or lower respiratory tract infections, gastrointestinal infections, cystitis or fever within the past 12 months. OUTLOOK: The cross-sectional analyses of data and tools presented here – for example on determinants of susceptibility to self-reported infections – can be anticipated from the year 2021 onward. Beyond that, more extensive research into infectious disease epidemiology will follow, particularly once analyses of GNC biological materials have been performed. HINTERGRUND: Infektionen spielen für das Krankheitsempfinden, für gesundheitsökonomische Überlegungen sowie Public Health in Deutschland weiterhin eine wichtige Rolle. Sie wurden in den letzten Jahren außerdem mit der Entstehung von nichtübertragbaren Erkrankungen in Zusammenhang gebracht. Die NAKO Gesundheitsstudie kann Erkenntnisse auf diesem Gebiet vertiefen und damit zielgenaueren präventiven Ansätzen den Weg bereiten. ZIEL: Die infektionsbezogenen Erhebungsinstrumente sollen beschrieben und in Bezug zu Erhebungsarten anderer deutscher Studien gesetzt werden. Zudem werden erste Daten zur Häufigkeit von Infektionskrankheiten berichtet. METHODEN: Fragen zu Infektionskrankheiten wurden in der NAKO-Basiserhebung sowohl im Interview als auch im Selbstausfüllerfragebogen (Touchscreen) gestellt. Es wurden die Daten der ersten 101.787 Teilnehmenden ausgewertet. ERGEBNISSE: Das Auftreten von Herpes Zoster (HZ), Post-Zoster-Neuralgie (bei Angabe von HZ), Hepatitis B/C, HIV/Aids und Tuberkulose im Sinne einer ärztlichen Diagnose bzw. von Sepsis als Grund für eine stationäre Behandlung wurde von 0,2 % (HIV/Aids) bis 8,6 % (HZ) der Befragten im Interview angegeben. Im Touchscreenmodul wurde das mindestens einmalige Auftreten einer Infektion der oberen Atemwege (IOA), der unteren Atemwege, des Magen-Darm-Traktes, der Harnblase oder von Fieber in den letzten 12 Monaten von 12 % (Zystitis) bis 81 % (IOA) berichtet. AUSBLICK: Weitere Ergebnisse anhand von Daten aus den hier vorgestellten Fragebögen sind im Querschnittsdesign – beispielsweise zu Determinanten der Anfälligkeit für selbst berichtete Infektionen – ab 2021 zu erwarten. Die Bearbeitung darüber hinausgehender Forschungsfragen der Infektionsepidemiologie wird insbesondere nach Analysen von NAKO-Bioproben möglich sein.

BACKGROUND: Asthma is one of the most common chronic diseases in both children and adults. Asthma first occurring in adulthood (adult-onset asthma, AOA) is associated with poorer prognosis compared to childhood-onset asthma (COA), which urgently calls for more research in this area. The aim of this work was to analyze the data on asthma collected in the German National Cohort and compare it with the German Health Interview and Examination Survey for Adults (DEGS), in particular regarding AOA. MATERIAL AND METHODS: Our analysis was based on the dataset of the main questionnaire at mid-term of the German National Cohort baseline examination, comprising 101,723 participants. Variables considered in the analyses were self-reported diagnosis of asthma, age at first diagnosis, asthma treatment in the past 12 months, age, and sex. RESULTS: In the midterm dataset, 8.7% of women and 7.0% of men in the German National Cohort reported that they had ever been diagnosed with asthma. Approximately one third of participants with asthma received their initial diagnosis before their 18th birthday. COA affected 2.2% of women and 2.8% of men, whereas AOA affected 6.5% of women and 4.2% of men. During the previous 12 months, 33% of COA cases and 60% of AOA cases were medically treated. CONCLUSION: The proportion of persons affected by asthma in the German National Cohort, as well as observed patterns regarding age and gender, corresponds to other data sources such as DEGS. However, in our analysis, the proportion of individuals with AOA was higher than described in the literature. The increase in cumulative asthma diagnoses with age is markedly steeper in younger participants, indicating a rising trend over time. HINTERGRUND: Asthma bronchiale stellt über alle Bildungsschichten hinweg eine der häufigsten chronischen Erkrankungen im Kindes- und Erwachsenenalter dar. Im Erwachsenenalter erstmals auftretendes Asthma (Adult-onset Asthma, AOA) ist im Vergleich zu Childhood-onset Asthma (COA) mit einer schlechteren Prognose assoziiert, was verstärkte Untersuchungen in diesem Bereich erfordert. Ziel der Arbeit war es, Häufigkeiten und das Alter bei Erstdiagnose aus Selbstangaben zu Asthma bei Erwachsenen in der NAKO Gesundheitsstudie darzustellen und mit Daten der Studie zur Gesundheit Erwachsener in Deutschland (DEGS) zu vergleichen. MATERIAL UND METHODEN: Unsere Analyse beruht auf einem Datensatz zur Halbzeit der NAKO-Basiserhebung mit 101.284 Personen. Verwendete Variablen waren die Selbstangabe zum jemals ärztlich diagnostizierten Asthma, Alter bei Erstdiagnose, Behandlung in den letzten 12 Monaten, Alter und Geschlecht. ERGEBNISSE: Laut Datenbasis zur Halbzeit berichteten in der NAKO 8,7 % der Frauen und 7,0 % der Männer, dass bei ihnen jemals Asthma diagnostiziert wurde. Etwa bei einem Drittel der Teilnehmenden mit Asthma wurde die Diagnose bereits im Kindes‑/Jugendalter (

Hintergrund Lärmbelästigung geht mit gesundheitlicher Beeinträchtigung und reduziertem Wohlbefinden einher. Die subjektive Lärmbelästigung steht im Zusammenhang mit der objektiven Lärmbelastung sowie individuellen und regionalen Faktoren. Fragestellung Wie viele Teilnehmende der NAKO Gesundheitsstudie fühlen sich durch nächtlichen Verkehrslärm belästigt und welche Faktoren stehen damit im Zusammenhang? Material und Methoden Diese Querschnittsanalyse basiert auf Daten von 86.080 NAKO-Teilnehmenden aus 18 Studienzentren, die von 2014 bis 2017 untersucht wurden. Um die Beziehungen zwischen individuellen und regionalen Faktoren und Verkehrslärmbelästigung in den Kategorien nicht belästigt, leicht/mittel und stark/sehr stark belästigt zu untersuchen, wurden multinomiale logistische Regressionsmodelle mit wechselseitiger Adjustierung der Faktoren verwendet. Ergebnisse Zwei Drittel der Teilnehmenden fühlten sich nicht durch Verkehrslärm belästigt; jeder Zehnte berichtete von starker/sehr starker Belästigung, mit den höchsten Anteilen in Berlin-Mitte und Leipzig. Die stärksten Assoziationen mit Lärmbelästigung wurden für Faktoren der individuellen Wohnsituation beobachtet, wie z. B. die Position des Schlafraums zur Hauptstraße (OR für leicht/mittel belästigt: 4,26 [95 % KI: 4,01; 4,52]; OR für stark/sehr stark belästigt: 13,36 [95 % KI: 12,47; 14,32] im Vergleich zu Garten/Innenhof). Teilnehmende im Alter von 40–60 Jahren oder der mittleren und niedrigen Einkommensklasse fühlten sich eher durch Verkehrslärm belästigt als jüngere bzw. ältere Teilnehmende oder solche mit hoher Einkommensklasse. Diskussion Teilnehmende der NAKO Gesundheitsstudie wiesen Unterschiede in der Belästigung durch nächtlichen Verkehrslärm in Bezug auf individuelle und regionale Faktoren auf., Background Noise annoyance is associated with adverse health-related conditions and reduced wellbeing. Thereby, subjective noise annoyance depends on the objective noise exposure and is modified by personal and regional factors. Objective How many participants of the German National Cohort Study (GNC; NAKO Gesundheitsstudie) were annoyed by transportation noise during nighttime and what factors were associated with noise annoyance? Materials and methods This cross-sectional analysis included 86,080 participants from 18 study centers, examined from 2014 to 2017. We used multinomial logistic regression to investigate associations of personal and regional factors to noise annoyance (slightly/moderately or strongly/extremely annoyed vs. not annoyed) mutually adjusting for all factors in the model. Results Two thirds of participants were not annoyed by transportation noise during nighttime and one in ten reported strong/extreme annoyance with highest percentages for the study centers Berlin-Mitte and Leipzig. The strongest associations were seen for factors related to the individual housing situation like the bedroom being positioned towards a major road (OR of being slightly/moderately annoyed: 4.26 [95% CI: 4.01;4.52]; OR of being strongly/extremely annoyed: 13.36 [95% CI: 12.47;14.32]) compared to a garden/inner courtyard. Participants aged 40–60 years and those in low- and medium-income groups reported greater noise annoyance compared to younger or older ones and those in the high-income group. Conclusion In this study from Germany, transportation noise annoyance during nighttime varied by personal and regional factors.

Summary The mammalian brain contains few niches for neural stem cells (NSCs) capable of generating new neurons, whereas other regions are primarily gliogenic. Here we leverage the spatial separation of the sub-ependymal zone NSC niche and the olfactory bulb, the region to which newly generated neurons from the sub-ependymal zone migrate and integrate, and present a comprehensive proteomic characterization of these regions in comparison to the cerebral cortex, which is not conducive to neurogenesis and integration of new neurons. We find differing compositions of regulatory extracellular matrix (ECM) components in the neurogenic niche. We further show that quiescent NSCs are the main source of their local ECM, including the multi-functional enzyme transglutaminase 2, which we show is crucial for neurogenesis. Atomic force microscopy corroborated indications from the proteomic analyses that neurogenic niches are significantly stiffer than non-neurogenic parenchyma. Together these findings provide a powerful resource for unraveling unique compositions of neurogenic niches., Graphical Abstract, Highlights • Proteomics define the NSC niche-specific extracellular matrix • Detergent-solubility profiling reveals extracellular matrix architecture • Transglutaminase 2 regulates neurogenesis • Stiffness is increased in the neurogenic niches of the brain, The physical properties of stem cell niches are thought to mediate important regulatory functions. Here we provide a proteomic resource of the neural stem cell niche in comparison to gliogenic brain parenchyma, highlighting stiffness and the enzyme transglutaminase 2 as key regulators of neurogenesis.

HINTERGRUND: Arterielle Hypertonie ist einwichtiger Risikofaktor für Herz-Kreislauf-Er-krankungen. Epidemiologische Studien führen meist drei konsekutive Blutdruckmessungen durch. Der 1. Messwert wird für Auswertungen verworfen, da dieser am stärksten durch vorhergehende Aktivitäten beeinflusst sein kann. Aus zeitlichen Gründen wurden in der NAKO Gesundheitsstudie nur zwei Messungen durchgeführt. FRAGESTELLUNG: Die vorliegende Analyse untersucht Auswirkungen methodischer Unterschiede bei der Blutdruckmessungauf die Hypertoniehäufigkeit und mittlere Blutdruckwerte anhand eines Vergleichsder ersten Hälfte der NAKO-Teilnehmenden(nur 2 Messungen) mit 5 deutschen populationsbasierten Studien (3 Messungen). MATERIAL UND METHODEN: Es wurden Daten der Teilnehmenden aus der NAKO (erste 101.816 Personen), der bundesweiten Studie zur Gesundheit Erwachsener des Robert Koch-Instituts (DEGS1) und aus 4 regionalen populationsbasierten Kohortenstudien (CARLA, HNR, KORA, SHIP) analysiert. Alters- und geschlechtsspezifische mittlere Blutdruckwerte und Hypertoniehäufigkeiten wurden auf Basis des 2. Messwertes, des Mittelwerts aus 1. und 2. sowie aus 2. und 3. Messung berechnet. ERGEBNISSE: Die mittleren Blutdruckwerte der beiden aktuellsten Studien (NAKO und DEGS1) sind sehr ähnlich und niedriger als in den anderen Studien. Die Differenz zwischen dem 2. Messwert und dem Mittelwert aus 2. und 3. Messung ist gering (maximale mittlere Abweichung: 1,5mmHg systolisch), jedoch ist die mittels des 2. Messwertes berechnete Hypertoniehäufigkeit der Bevölkerung höher als bei Verwendung des Mittelwertsaus 2. und 3. Messung. DISKUSSION: Die Ergebnisse der vorliegenden Analyse zeigen, dass für die wissenschaftliche Auswertung der NAKO-Daten die Verwendung des 2. Blutdruckmesswerts zu empfehlen ist. BACKGROUND: Arterial hypertension is an important risk factor for cardiovascular diseases. Epidemiological studies typically perform three consecutive blood pressure measurements. The first measurement is discarded in subsequent analyses, as this value may be strongly affected by previous activities. Due to time constraints the German National Cohort (GNC NAKO) performed only two blood pressure measurements. OBJECTIVES. The present analysis examined the possible effects of methodological differences in blood pressure measurement by comparing the first 101,816 GNC participants (two blood pressure measurements) with those of five German population-based studies (three measurements). MATERIALS AND METHODS: Blood pressure data from participants aged 20 to 79 years from the GNC, the German Health Interview and Examination Survey for Adults by the Robert Koch Institute (DEGS1), and four regional population-based cohort studies (CARLA, HNR, KORA, SHIP) were used to calculate age-and sex-specific mean blood pressure values and hypertension frequencies based on the second blood pressure measurement, the arithmetic mean of the first and second value and of the second and third (the latter not available in the GNC). RESULTS: The mean blood pressure values of the two most recent studies (GNC, DEGS1) were very similar and lower than in the other studies. The difference of the second measurement and the mean of second and third measurement was small (maximum mean difference: 1.5mmHg systolic blood pressure), but leads to higher estimated hypertension frequencies. CONCLUSIONS: The current results show that using the second blood pressure measurement should be recommended for scientific analyses of GNC data.

To ameliorate effects of social inequalities on children's development the German federal state law for child day care and preschools provides additional funds for day care centers in socioeconomically deprived regions in Mecklenburg-Western Pomerania. The goal of these funds is to support three to six year old children with developmental risks. Day care centers can choose to use these funds for the employment of additional staff. Our study aims to investigate whether the number of weekly working hours provided by this additional staff is associated with a reduction of developmental risks in 4 competence areas over one year. A multilevel linear model (n = 83 day care centers) reveals that additional working hours decrease the prevalence of children with developmental risks. These results provide evidence for a beneficial effect of the federal state law.

Collective cell migration is essential for morphogenesis, tissue remodelling and cancer invasion. In vivo, groups of cells move in an orchestrated way through tissues. This movement involves mechanical as well as molecular interactions between cells and their environment. While the role of molecular signals in collective cell migration is comparatively well understood, how tissue mechanics influence collective cell migration in vivo remains unknown. Here we investigated the importance of mechanical cues in the collective migration of the Xenopus laevis neural crest cells, an embryonic cell population whose migratory behaviour has been likened to cancer invasion. We found that, during morphogenesis, the head mesoderm underlying the cephalic neural crest stiffens. This stiffening initiates an epithelial-to-mesenchymal transition in neural crest cells and triggers their collective migration. To detect changes in their mechanical environment, neural crest cells use mechanosensation mediated by the integrin-vinculin-talin complex. By performing mechanical and molecular manipulations, we show that mesoderm stiffening is necessary and sufficient to trigger neural crest migration. Finally, we demonstrate that convergent extension of the mesoderm, which starts during gastrulation, leads to increased mesoderm stiffness by increasing the cell density underneath the neural crest. These results show that convergent extension of the mesoderm has a role as a mechanical coordinator of morphogenesis, and reveal a link between two apparently unconnected processes-gastrulation and neural crest migration-via changes in tissue mechanics. Overall, we demonstrate that changes in substrate stiffness can trigger collective cell migration by promoting epithelial-to-mesenchymal transition in vivo. More broadly, our results raise the idea that tissue mechanics combines with molecular effectors to coordinate morphogenesis.

Medical implants offer a unique and powerful therapeutic approach in many areas of medicine. However, their lifetime is often limited as they may cause a foreign body reaction (FBR) leading to their encapsulation by scar tissue1–4. Despite the importance of this process, how cells recognise implanted materials is still poorly understood5, 6. Here, we show how the mechanical mismatch between implants and host tissue leads to FBR. Fibroblasts and macrophages, which are both crucially involved in mediating FBR, became activated when cultured on materials just above the stiffness found in healthy tissue. Coating implants with a thin layer of hydrogel or silicone with a tissue-like elastic modulus of ∼1 kPa or below led to significantly reduced levels of inflammation and fibrosis after chronic implantation both in peripheral nerves and subcutaneously. This effect was linked to the nuclear localisation of the mechanosensitive transcriptional regulator YAP in vivo. Hence, we identify the mechanical mismatch between implant and tissue as a driver of FBR. Soft implant coatings matching the mechanical properties of host tissue minimized FBR and may be used as a novel therapeutic strategy to improve long-term biomedical implant stability without extensive modification of current implant manufacturing techniques, thus facilitating clinical translation. One sentence summary Foreign body reaction to medical implants can be avoided by matching the stiffness of the implant surface to that of the host tissue.

High-protein diet is a promising strategy for diabetes treatment supporting body weight control, improving glycaemic status, cardiovascular risk factors and reducing liver fat. Here, we investigated effects of diets high in animal (AP) or plant (PP) protein on oxidative stress and antioxidant status in individuals with type 2 diabetes (T2DM). 37 obese individuals (age 64.3 ± 1.0 years) with T2DM were randomized to an isocaloric diet (30 energy(E)% protein, 30 E% fat and 40 E% carbohydrates) rich in AP or PP for 6 weeks. Markers of oxidative and nitrosative stress and antioxidant status in plasma and nitrate/nitrite levels in urine were assessed. Gene expression in subcutaneous adipose tissue (SAT) was analysed by RNA-Seq and real-time PCR. Both AP and PP diets similarly reduced plasma levels of malondialdehyde (PAP = 0.003, PPP = 1.6 × 10−4) and protein carbonyls (PAP = 1.2 × 10−4, PPP = 3.0 × 10−5) over 6 weeks. Nitrotyrosine (NT) increased upon both AP and PP diets (PAP = 0.005, PPP = 0.004). SAT expression of genes involved in nitric oxide (NO) and oxidative stress metabolism and urine NO metabolite (nitrate/nitrite) levels were not changed upon both diets. Plasma levels of carotenoids increased upon PP diet, whereas retinol, alpha- and gamma-tocopherol slightly decreased upon both diets. AP and PP diets similarly improve oxidative stress but increase nitrosative stress markers in individuals with T2DM. Mechanisms of the NT regulation upon high-protein diets need further investigation., Graphical abstract Image 1, Highlights • Effects of 6-week isocaloric diets high in animal (AP) or plant (PP) protein in subjects with type 2 diabetes were studied. • AP and PP diets reduced plasma levels of malondialdehyde and protein carbonyls and increased nitrotyrosine. • Expression of genes of nitric oxide (NO) and oxidative stress metabolism and urine NO metabolite levels were not changed. • Plasma retinol and tocopherol decreased upon both diets, and carotenoids increased upon PP diet.

Studies of mechanical signalling are typically performed by comparing cells cultured on soft and stiff hydrogel-based substrates. However, it is challenging to independently and robustly control both substrate stiffness and tethering of extracellular matrix (ECM) to substrates, making ECM tethering a potentially confounding variable in mechanical signalling investigations. Moreover, poor ECM tethering can lead to weak cell attachment. To address this, we developed StemBond hydrogels, a hydrogel formulation in which ECM tethering is stable and can be varied independently of stiffness. We show that soft StemBond hydrogels provide an optimal format for culturing embryonic stem (ES) cells. We find that soft StemBond substrates improve the homogeneity of ES cell populations, boost their self-renewal, and increase the efficiency of cellular reprogramming. Our findings underline how soft microenvironments impact mechanosensitive signalling pathways regulating self-renewal and differentiation, indicating that optimising the complete mechanical microenvironment will offer greater control over stem cell fate specification.

Summary Basement membranes (BMs) are specialized extracellular matrices required for tissue organization and organ formation. We study the role of laminin and its integrin receptor in the regulation of tissue migration during Drosophila oogenesis. Egg production in Drosophila involves the collective migration of follicle cells (FCs) over the BM to shape the mature egg. We show that laminin content in the BM increases with time, whereas integrin amounts in FCs do not vary significantly. Manipulation of integrin and laminin levels reveals that a dynamic balance of integrin-laminin amounts determines the onset and speed of FC migration. Thus, the interplay of ligand-receptor levels regulates tissue migration in vivo. Laminin depletion also affects the ultrastructure and biophysical properties of the BM and results in anterior-posterior misorientation of developing follicles. Laminin emerges as a key player in the regulation of collective cell migration, tissue stiffness, and the organization of anterior-posterior polarity in Drosophila., Graphical Abstract, Highlights • Follicle cells with constant integrin levels face increasing laminin in fly oogenesis • Integrin-laminin levels fix the timing and speed of egg chamber rotation in vivo • Laminin depletion affects the ultrastructure and biophysical properties of the ECM • Laminin depletion results in anterior-posterior misorientation of developing follicles, Collective cell migration requires cell-ECM interactions. Using the fruit fly ovary, Díaz de la Loza et al. find that the ECM component laminin controls the onset and speed of epithelial sheet migration. Because laminin depletion also results in aberrant anterior-posterior polarity, laminin regulates coordinated migration during organogenesis and maintains axial polarity.

Local tissue stiffness provides an important signal to which cells respond in vivo. However, assessing tissue mechanics is currently challenging and requires sophisticated technology. We here developed a model quantitatively predicting nervous tissue stiffness heterogeneities at cellular resolution based on cell density, myelin and GFAP fluorescence intensities. These histological parameters were identified by a correlation analysis of atomic force microscopy-based elasticity maps of spinal cord sections and immunohistochemical stainings. Our model provides a simple tool to estimate local stiffness distributions in nervous tissue, and it can easily be expanded to other tissue types, thus paving the way for studies of the role of mechanical signals in development and pathology.

Tissue mechanics is important for development; however, the spatio-temporal dynamics of in vivo tissue stiffness is still poorly understood. We here developed tiv-AFM, combining time-lapse in vivo atomic force microscopy with upright fluorescence imaging of embryonic tissue, to show that in the developing Xenopus brain, a stiffness gradient evolves over time because of differential cell proliferation. Subsequently, axons turn to follow this gradient, underpinning the importance of time-resolved mechanics measurements.

A laser ablation system (LA) was coupled to an in-house developed low-flow inductively coupled plasma ion source for mass spectrometry (ICP-MS). In this setup, the low-flow torch showed best analytical performance at a total argon gas flow rate of only 1.27 L min−1 and a generator power of 900 W. The optimized system was applied to elemental bioimaging. Two different sections of one kidney sample were analyzed and images of the elements Al and Br from the staining agents hematoxylin and eosin, respectively, and I from a contrast agent iodixanol were recorded selectively and with high sensitivity. For detection of the elements, the mass traces 27Al, 79Br, 81Br, and 127I were selected to demonstrate the system's analytical performance over a wide mass range. In total, the argon consumption could be reduced by >90% compared to conventional ICP-MS systems.

Mutations of the tricarboxylic acid cycle enzyme fumarate hydratase cause hereditary leiomyomatosis and renal cell cancer1. Fumarate hydratase-deficient renal cancers are highly aggressive and metastasize even when small, leading to a very poor clinical outcome2. Fumarate, a small molecule metabolite that accumulates in fumarate hydratase-deficient cells, plays a key role in cell transformation, making it a bona fide oncometabolite3. Fumarate has been shown to inhibit α-ketoglutarate-dependent dioxygenases that are involved in DNA and histone demethylation4, 5. However, the link between fumarate accumulation, epigenetic changes, and tumorigenesis is unclear. Here we show that loss of fumarate hydratase and the subsequent accumulation of fumarate in mouse and human cells elicits an epithelial-to-mesenchymal-transition (EMT), a phenotypic switch associated with cancer initiation, invasion, and metastasis6. We demonstrate that fumarate inhibits Tet-mediated demethylation of a regulatory region of the antimetastatic miRNA cluster6 mir-200ba429, leading to the expression of EMT-related transcription factors and enhanced migratory properties. These epigenetic and phenotypic changes are recapitulated by the incubation of fumarate hydratase-proficient cells with cell-permeable fumarate. Loss of fumarate hydratase is associated with suppression of miR-200 and the EMT signature in renal cancer and is associated with poor clinical outcome. These results imply that loss of fumarate hydratase and fumarate accumulation contribute to the aggressive features of fumarate hydratase-deficient tumours.

In our eyes, as in the eyes of all vertebrates, images of the environment are projected on­to an inverted retina, where photons must pass through most of the retinal layers before being captured by the light-sensitive cells. Light scattering in these retinal layers must decrease the signal-to-noise ratio of the im­ages and thus interfere with clear vision. Sur­prisingly however, our eyes display splendid visual abilities. This apparent contradiction could be resolved if intraretinal light scatter­ing were to be minimized by built-in opti­cal elements that facilitate light transmission through the tissue. Indeed, we were able to show that one function of radial glial (Mül­ler) cells is to act as effective optical fibers in the living retina, bypassing the light-scatter­ing structures in front of the light-sensitive cells. Each Müller cell serves as a ‘private’ light cable, providing one individual cone photo­receptor cell with its appropriate pixel of the environmental image, thus optimizing spe­cial resolution and visual acuity.

Hintergrund: Einschulungsuntersuchungen in Mecklenburg-Vorpommern (M-V) belegen eine hohe Pravalenz motorischer Entwicklungsverzogerungen (13,7%). Im Folgenden wurden mogliche Risikofaktoren (RF) fur vorausgehende Entwicklungsgefahrdungen analysiert. Methodik: „Kinder in Kitas (KiK)“ wurde als cluster-randomisierte, prospektive, kontrollierte Studie in 12 Kindertageseinrichtungen (Kitas) in M-V durchgefuhrt. Entwicklungsgefahrdungen wurden anhand des „Dortmunder Entwicklungsscreening fur den Kindergarten DESK 3–6“ ­erfasst. Bei den Eltern fand ein standardisierter Fragebogen Anwendung. RF wurden in binar logistischen Regressionen fur die Fein- (FM) und die Grobmotorik (GM) berechnet. Ergebnisse: N=599 Kinder wurden in die Analysen einbezogen. RF fur Entwicklungsgefahrdungen in FM und GM sind unter anderem ein unregelmasiger Kitabesuch (FM: OR: 2,63; p=0,009; 95%KI: 1,27–5,45; GM: OR: 2,56; p=0,021; 95%KI: 1,15–5,68) und das mannliche Geschlecht (FM: OR: 2,97; p Schlussfolgerung: Ein regelmasiger Kitabesuch wirkt positiv auf die motorische Entwicklung. Die Ergebnisse unterstreichen die besondere Eignung dieses Settings fur Fordermasnahmen.

Introduction Cryptococcosis is an opportunistic mycosis, especially in patients that are human immunodeficiency virus (HIV)-positive, and frequently involves the central nervous system. Methods We assessed the potential of ventriculoperitoneal shunting (VPS) in preventing mortality due to uncontrollable intracranial hypertension (ICH) in 15 patients with acquired immunodeficiency syndrome (AIDS)-related cryptococcal meningitis. Results After 2 weeks of antifungal therapy consisting of amphotericin B deoxycholate with or without fluconazole, patients with persistent ICH underwent VPS, despite having persistent Cryptococcus neoformans infection. In 12 patients, the uncontrollable ICH was resolved by VPS. Conclusions Patients with cryptococcal meningoencephalitis who have ICH must be considered for VPS even with positive cerebrospinal fluid cultures.