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Pancreatic lineage specification follows the formation of tripotent pancreatic progenitors (PPs). Current protocols rebuilding PPs have an endocrine lineage bias and are mostly based on PDX1/NKX6-1 coexpression neglecting other markers decisive for PP heterogeneity and lineage potential. However, true tripotent PPs are of utmost interest to study also exocrine disorders such as pancreatic cancer and to simultaneously generate all three pancreatic lineages from the same ancestor. Here, we performed a comprehensive compound testing to advance the generation of multipotent progenitors, which were further characterized for their trilineage potential and . The heterogeneity and cell-cell communication across the PP subpopulations were analyzed via single-cell transcriptomics. We introduce a novel PP differentiation platform based on a comprehensive compound screening with an advanced computing tool to reduce impurities and to increase Glycoprotein-2 expression and subsequent trilineage potential. Superior PP tripotency was proven by the generation of acinar, endocrine, and ductal cells as well as upon orthotopic transplantation revealing all three lineages at fetal maturation level. GP2 expression levels at PP stage ascribed varying pancreatic lineage potential. Intermediate and high GP2 levels were superior in generating endocrine and duct-like organoids (PDLO). FACS-based purification of the GP2 PPs allowed the generation of pancreatic acinar-like organoids (PALO) with proper morphology and expression of digestive enzymes. scRNA-seq confirmed multipotent identity, positioned the GP2/PDX1/NKX6-1 population next to human fetal tip and trunk progenitors and identified novel ligand-receptor (LR) interactions in distinct PP subpopulations. LR validation experiments licensed midkine and VEGF signaling to increase markers labelling the single cell clusters with high GP2 expression. In this study, we guide human pluripotent stem cells into multipotent pancreatic progenitors. This common precursor population, which has the ability to mature into acinar, ductal and functional β-cells, serves as a basis for studying developmental processes and deciphering early cancer formation in a cell type-specific context. Using single-cell RNA sequencing and subsequent validation studies, we were able to dissect PP heterogeneity and specific cell-cell communication signals.

Site-directed RNA editing might provide a safer or more effective alternative to genome editing in certain clinical scenarios. Until now, RNA editing has relied on overexpression of exogenous RNA editing enzymes or of endogenous human ADAR (adenosine deaminase acting on RNA) enzymes. Here we describe the engineering of chemically optimized antisense oligonucleotides that recruit endogenous human ADARs to edit endogenous transcripts in a simple and programmable way, an approach we call RESTORE (recruiting endogenous ADAR to specific transcripts for oligonucleotide-mediated RNA editing). We observed almost no off-target editing, and natural editing homeostasis was not perturbed. We successfully applied RESTORE to a panel of standard human cell lines and human primary cells and demonstrated repair of the clinically relevant PiZZ mutation, which causes α1-antitrypsin deficiency, and editing of phosphotyrosine 701 in STAT1, the activity switch of the signaling factor. RESTORE requires only the administration of an oligonucleotide, circumvents ectopic expression of proteins, and represents an attractive approach for drug development. Endogenous RNAs are edited using antisense oligos that recruit endogenous RNA-editing enzymes.

Human pluripotent stem cells can be differentiated into the pancreatic lineage, providing a human pancreas model to study diseases and development. We improved the differentiation protocol to generate pancreatic progenitors, the common ancestor of the endocrine and exocrine pancreas. We classified the glycoprotein-2 high-expressing subpopulation as truly multipotent, thereby making it particularly suitable to engineer acinar cells. Its capability of developing simultaneously into endocrine, ductal and acinar lineages qualifies it as a useful tool for pancreatic disease modelling.

Human stem cell-based differentiation systems are increasingly used to model diseases, advancing molecular research on pathomechanisms by allowing for the introduction of disease-relevant gene modifications and testing potential treatments and treatment outcomes. However, these directed differentiation processes often face limitations, as many resulting cell types remain distinct from their adult counterparts or contain a notable proportion of unwanted contaminating cell types. This underscores the need for ongoing improvement and refinement.In this study, a systematic stage-wise compound testing approach was applied to optimize the pancreatic progenitor differentiation process. The newly generated PPs showed increased levels of the progenitor marker GP2 and a reduced presence of non-pancreatic cell types. Single-cell transcriptomics revealed considerable heterogeneity within the uniformly PDX1/NKX6.1-positive progenitor pool, with subpopulations distinguished by GP2 expression patterns. Close clustering with human fetal tip and trunk cells, along with FACS-based enrichment, identified the GP2high-expressing cluster as a multipotent progenitor group capable of differentiating into acinar, ductal, and endocrine lineages. Incorporating an ex vivo culture method further supported maturation and long-term cultivation of pancreatic cell types, providing an alternative to transplantation studies in mice.Altogether, the generation of this multipotent progenitor population, capable of giving rise to all three lineages of the pancreas, holds significant potential, given that many diseases, such as diabetes, pancreatitis or pancreatic cancer, often impact both the exocrine and endocrine compartments. Understanding the crosstalk, interactions, and mutual influences among different pancreatic cell types is increasingly important for studying complex disease mechanisms and recognizing the pancreas as a multifaceted organ with interconnected endocrine and exocrine functions.In the second part of this doctoral study, the optimized pancreatic progenitor differentiation system was used to model neonatal diabetes disease, providing an ideal platform for investigating inherited diseases affecting pancreas development and function. The case involved a boy suffering from severe neonatal diabetes and carrying a heterozygous mutation in ONECUT1. Although ONECUT1 protein truncating variants typically cause neonatal diabetes in a recessive manner, his phenotype could not be explained by the heterozygous ONECUT1 variant alone. In addition, the patient exhibited a deletion in a non-coding region upstream of ONECUT1. We used the optimized stem cell-based pancreatic differentiation system and deciphered the pathomechanisms, identifying a putative cis-acting enhancer of ONECUT1 within the non-coding region. This system further supported the development of a tailored therapy option for affected patients with similar genetic profiles. Understanding such monogenic disease mechanisms holds broad relevance. Variants in these genes or their regulatory regions are often linked to a predisposition for polygenic diabetes. This genetic overlap between different forms of diabetes suggests shared pathophysiological mechanisms, aiding in better subtyping and comprehension of the syndromic and heterogenous nature of diabetes. Numerous monogenic gene variants were identified in the recent years, but the most are located in the non-coding regions of unknown function. To accurately assess the disease-causing potential of these variants, it is crucial to decipher the regulatory mechanisms - including promoters, enhancers, silencers or lncRNAs - active during pancreatic development and in mature islets.

Unklar ist, ob sich die Rolle der Diagnostik mittels Magnetresonanztomographie (MRT) von Beckenfrakturen mit der Epidemiologie verändert hat. Ziel dieser retrospektiven Studie war es herauszuarbeiten, wie häufig und bei welchen Beckenfrakturpatienten die MRT eingesetzt worden war und ob daraus ein Informationszugewinn sowie eine Änderung des Therapieregimes resultierten.Insgesamt untersuchten wir retrospektiv 140 Patienten mit einer Becken- und/oder Acetabulumfraktur des Bundeswehrkrankenhauses Ulm in den Jahren 2013 - 2015. Das Teilkollektiv „mit MRT“ (31 Patienten) wies tendenziell mehr weibliche Patienten auf (71 % „mit MRT“, 49 % „ohne MRT“) und war tendenziell älter (Median 81 Jahre „mit MRT“ und 62 Jahre „ohne MRT“) als das Teilkollektiv „ohne MRT“ mit 109 Patienten. Tendenziell gab es im Teilkollektiv „mit MRT“ mehr inadäquate und im Teilkollektiv „ohne MRT“ mehr adäquate Traumata. In beiden Teilkollektiven trat die isolierte Beckenringfraktur am häufigsten auf und beide Teilkollektive wurden häufiger operativ als konservativ versorgt. In der Diagnostik der Acetabulumfrakturen spielte die MRT keine Rolle. Die mediane Aufenthaltsdauer der beiden Teilkollektive unterschied sich tendenziell nicht (14 Tage „mit MRT“ versus 16 Tage „ohne MRT“), Patienten „mit MRT“ wurden aber tendenziell später (im Median 8 Tage nach Aufnahme) operiert als Patienten „ohne MRT“ (2 Tage).Häufigste Indikation zur MRT war die Abklärung von Frakturen des posterioren Beckenringes nach inadäquatem Trauma bei persistierender Symptomatik und/oder inkonklusiver Röntgen- / Computertomographie(CT)-Diagnostik. Im Median folgte die MRT drei Tage nach der CT. Bei 78 % der MRT-Patienten führte sie zu einem Informationszugewinn (Änderung des Frakturausmaßes / -typs und/oder zusätzlich erkannte Begleitverletzungen / Nebenbefunde), insbesondere bei Frakturen nach inadäquatem Trauma. Die MRT hatte allerdings in unserem kleinen Studienkollektiv retrospektiv tendenziell keinen Einfluss auf die Therapie (konservativ versus operativ).Wir empfehlen die MRT-Bildgebung bei älteren, weiblichen Patientinnen nach inadäquatem Trauma durchzuführen, um das wahre Frakturausmaß zu identifizieren. Somit könnten eine zeitverzögerte Diagnostik und damit eine spätere Therapie (konservativ / operativ) sowie längere Liegedauer (= höhere Mortalität) vermieden werden.Tatsächlich fehlen derzeit ausreichende Daten, um eine klare eindeutige Empfehlung für die Indikation zur MRT bei genanntem Patientenklientel aussprechen zu können. Des Weiteren sollte der tatsächliche Mehrgewinn aus der MRT gegenüber der CT in größeren prospektiven Studien belegt werden.

A radio communication network can be modeled by a digraph,$D$ , where there is an arc from vertex$x$to vertex$y$if a signal sent from$x$can be received at$y$ . The competition graph,$C( D )$ , of this network has the same vertex set as$D$ , and$( x,y )$is an edge in$C( D )$if there is a vertex$z$such that$( x,z )$and$( y,z )$are arcs in$D$ . The competition graph can be used to assist in assigning frequencies to the transmitters in the network. Usually the digraphs for these networks are strongly connected, but the power of transmitters may vary, so they are not necessarily symmetric. Therefore it is of interest to determine which graphs are the competition graphs of strongly connected digraphs. We characterize these graphs as well as establish several large classes of graphs, including chordal, interval, and some triangle-free graphs, which are competition graphs of loopless Hamiltonian digraphs.

Purpose Sleep disturbance and cancer-related fatigue (CRF) are among the most commonly reported symptoms associated with breast cancer and its treatment. This study identified symptom cluster groups of breast cancer patients based on multidimensional assessment of sleep disturbance and CRF prior to and during chemotherapy. Methods Participants were 152 women with stage I–IIIA breast cancer. Data were collected before chemotherapy (T1) and during the final week of the fourth chemotherapy cycle (T2). Latent profile analysis was used to derive groups of patients at each timepoint who scored similarly on percent of the day/night asleep per actigraphy, the Pittsburgh Sleep Quality Index global score, and the five subscales of the Multidimensional Fatigue Symptom Inventory-Short Form. Bivariate logistic regression evaluated if sociodemographic/medical characteristics at T1 were associated with group membership at each timepoint. Results Three groups (Fatigued with sleep complaints, Average, Minimal symptoms) were identified at T1, and five groups (Severely fatigued with poor sleep, Emotionally fatigued with average sleep, Physically fatigued with average sleep, Average, Minimal symptoms) at T2. The majority of individuals in a group characterized by more severe symptoms at T1 were also in a more severe symptom group at T2. Sociodemographic/medical variables at T1 were significantly associated with group membership at T1 and T2. Conclusions This study identified groups of breast cancer patients with differentially severe sleep disturbance and CRF symptom profiles prior to and during chemotherapy. Identifying groups with different symptom management needs and distinguishing groups by baseline sociodemographic/medical variables can identify patients at risk for greater symptom burden.

The fossil record of the terminal Ediacaran Period is typified by the iconic index fossil Cloudina and its relatives. These tube-dwellers are presumed to be primitive metazoans, but resolving their phylogenetic identity has remained a point of contention. The root of the problem is a lack of diagnostic features; that is, phylogenetic interpretations have largely centered on the only available source of information—their external tubes. Here, using tomographic analyses of fossils from the Wood Canyon Formation (Nevada, USA), we report evidence of recognizable soft tissues within their external tubes. Although alternative interpretations are plausible, these internal cylindrical structures may be most appropriately interpreted as digestive tracts, which would be, to date, the earliest-known occurrence of such features in the fossil record. If this interpretation is correct, their nature as one-way through-guts not only provides evidence for establishing these fossils as definitive bilaterians but also has implications for the long-debated phylogenetic position of the broader cloudinomorphs. Cloudinomorphs were one of the few groups to survive from the Ediacaran into the Cambrian, but they are known only from their external tubes. Here, Schiffbauer et al. report soft-tissue preservation of cloudinomorphs; the internal structures are interpreted as guts characteristic of bilaterians.

Static contact angle measurements are one of the most popular methods to analyze the wetting behavior of materials of any kind. Although this method is readily applicable without the need of sophisticated machinery, the results obtained for the very same material may vary strongly. The sensitivity of the measurement against environmental conditions, sample preparation and measurement conduction is a main factor for inconsistent results. Since often no detailed measurement protocols exist alongside published data, contact angle values as well as elaborated wetting studies do not allow for any comparison. This paper therefore aims to discuss possible influences on static contact angle measurements and to experimentally demonstrate the extent of these effects. Sample storage conditions, cleaning procedures, droplet volume, water grade and droplet application as well as the influence of evaporation on the static contact angle are investigated in detail. Especially sample storage led to differences in the contact angle up to 60%. Depending on the wetting state, evaporation can reduce the contact angle by 30–50% within 10 min in dry atmospheres. Therefore, this paper reviews an existing approach for a climate chamber and introduces a new measuring setup based on these results. It allows for the observation of the wetting behavior for several minutes by successfully suppressing evaporation without negatively affecting the surface prior to measurement by exposure to high humidity environments.