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Abstract Mutations in the transcription factor C/EBPα are found in ~10% of all acute myeloid leukaemia (AML) cases but the contribution of these mutations to leukemogenesis is incompletely understood. We here use a mouse model of granulocyte progenitors expressing conditionally active HoxB8 to assess the cell biological and molecular activity of C/EBPα-mutations associated with human AML. Both N-terminal truncation and C-terminal AML-associated mutations of C/EBPα substantially altered differentiation of progenitors into mature neutrophils in cell culture. Closer analysis of the C/EBPα-K313-duplication showed expansion and prolonged survival of mutant C/EBPα-expressing granulocytes following adoptive transfer into mice. C/EBPα-protein containing the K313-mutation further showed strongly enhanced transcriptional activity compared with the wild-type protein at certain promoters. Analysis of differentially regulated genes in cells overexpressing C/EBPα-K313 indicates a strong correlation with genes regulated by C/EBPα. Analysis of transcription factor enrichment in the differentially regulated genes indicated a strong reliance of SPI1/PU.1, suggesting that despite reduced DNA binding, C/EBPα-K313 is active in regulating target gene expression and acts largely through a network of other transcription factors. Strikingly, the K313 mutation caused strongly elevated expression of C/EBPα-protein, which could also be seen in primary K313 mutated AML blasts, explaining the enhanced C/EBPα activity in K313-expressing cells.

Portal vein thrombosis (PVT) is a rare disease with an incidence of 0.7/100,000 inhabitants per year. Septic PVT (pylephlebitis) usually occurs secondary to infection in the anatomic region drained by the portal venous system. We report on a 76-year-old German male who was admitted with a history of recurrent fever and acute renal failure. Blood cultures taken on admission showed Escherichia coli, as well as Bacteroides uniformis after an extended incubation period of 90 h. In addition, infection with Leptospira spp. was diagnosed serologically. Computerized tomography of the abdomen revealed an extensive PVT along with signs of colonic diverticulitis. Symptoms resolved under prolonged antimicrobial therapy with beta-lactams and adequate heparinization. A myeloproliferative disorder could be excluded. There was no evidence of an underlying coagulation disorder. Imaging controls showed an almost complete resolution of the PVT after 6 months of anticoagulation therapy. To the best of our knowledge, this is the first report of such an “unhappy triad,” which includes atypical manifestations of leptospirosis and involvement of other intestinal bacteria.

Recent research suggests that treating only mental disorders may not be sufficient to reduce the risk for future suicidal behavior in patients with a suicide attempt(s). It is therefore necessary to pay special therapeutic attention to past suicidal acts. Thus, the newly developed RISE (Relapse Prevention Intervention after Suicidal Event) program was built on the most effective components of existing psychotherapeutic and psychosocial interventions according to our current meta-analysis. The RISE program consists of five individual sessions designed for the acute psychiatric inpatient setting. The main goals of the treatment are to decrease future suicidal events and to improve patients' ability to cope with future suicidal crises. In the present study, feasibility and acceptance of the RISE program were investigated as well as its clinical effects on suicidal ideations, mental pain, self-efficacy and depressive symptoms. We recruited a sample of 27 inpatients of the Department of Psychiatry and Psychotherapy, University Hospital Jena, Germany. The final sample consisted of 20 patients hospitalized for a recent suicide attempt, including 60 percent of multiple attempters. The data collection included a structured interview and a comprehensive battery of questionnaires to evaluate the feasibility and acceptance of the RISE program as well as associated changes in clinical symptoms. A follow-up examination was carried out after 6 months. Considering the low dropout rate and the overall positive evaluation, the RISE program was highly accepted in a sample of severely impaired patients. The present study also demonstrated that the levels of suicidal ideations, mental pain, depressive symptoms, and hopelessness decreased significantly after RISE. Since all of these clinical parameters are associated with the risk of future suicidal behavior, a potential suicide-preventive effect of the intervention can be inferred from the present findings. The positive results of the follow-up assessment after 6 months point in the same direction. In addition, RISE treatment increased self-efficacy in patients, which is an important contributor for better coping with future suicidal crises. Thus, present study demonstrate that RISE is a suitable therapy program for the treatment of patients at high risk for suicidal behavior in an acute inpatient setting.

Abstract Background Repeat elements constitute a large proportion of the human genome and recent evidence indicates that repeat element expression has functional roles in both physiological and pathological states. Specifically for cancer, transcription of endogenous retrotransposons is often suppressed to attenuate an anti-tumor immune response, whereas aberrant expression of heterochromatin-derived satellite RNA has been identified as a tumor driver. These insights demonstrate separate functions for the dysregulation of distinct repeat subclasses in either the attenuation or progression of human solid tumors. For hematopoietic malignancies, such as Acute Myeloid Leukemia (AML), only very few studies on the expression/dysregulation of repeat elements were done. Methods To study the expression of repeat elements in AML, we performed total-RNA sequencing of healthy CD34 + cells and of leukemic blast cells from primary AML patient material. We also developed an integrative bioinformatic approach that can quantify the expression of repeat transcripts from all repeat subclasses (SINE/ALU, LINE, ERV and satellites) in relation to the expression of gene and other non-repeat transcripts (i.e. R/G ratio). This novel approach can be used as an instructive signature for repeat element expression and has been extended to the analysis of poly(A)-RNA sequencing datasets from Blueprint and TCGA consortia that together comprise 120 AML patient samples. Results We identified that repeat element expression is generally down-regulated during hematopoietic differentiation and that relative changes in repeat to gene expression can stratify risk prediction of AML patients and correlate with overall survival probabilities. A high R/G ratio identifies AML patient subgroups with a favorable prognosis, whereas a low R/G ratio is prevalent in AML patient subgroups with a poor prognosis. Conclusions We developed an integrative bioinformatic approach that defines a general model for the analysis of repeat element dysregulation in physiological and pathological development. We find that changes in repeat to gene expression (i.e. R/G ratios) correlate with hematopoietic differentiation and can sub-stratify AML patients into low-risk and high-risk subgroups. Thus, the definition of a R/G ratio can serve as a valuable biomarker for AML and could also provide insights into differential patient response to epigenetic drug treatment.

Understanding SARS-CoV-2 breakthrough infections in vaccinated healthcare workers is of key importance in mitigating the effects of the COVID-19 pandemic in healthcare facilities. An observational prospective cohort study was conducted in vaccinated employees with acute SARS-CoV-2 infection between October 2021 and February 2022. Serological and molecular testing was performed to determine SARS-CoV-2 viral load, lineage, antibody levels, and neutralizing antibody titers. A total of 571 (9.7%) employees experienced SARS-CoV-2 breakthrough infections during the enrolment period, of which 81 were included. The majority (n = 79, 97.5%) were symptomatic and most (n = 75, 92.6%) showed Ct values < 30 in RT-PCR assays. Twenty-four (30%) remained PCR-positive for > 15 days. Neutralizing antibody titers were strongest for the wildtype, intermediate for Delta, and lowest for Omicron variants. Omicron infections occurred at higher anti-RBD-IgG serum levels (p = 0.00001) and showed a trend for higher viral loads (p = 0.14, median Ct difference 4.3, 95% CI [−2.5–10.5]). For both variants, viral loads were significantly higher in participants with lower anti-RBD-IgG serum levels (p = 0.02). In conclusion, while the clinical course of infection with both the Omicron and Delta variants was predominantly mild to moderate in our study population, waning immune response over time and prolonged viral shedding were observed.

The properties of particle ensembles are defined by a complex multidimensional parameter space, namely particle size, shape, surface, structure, composition and their distributions. Macroscopic product properties are a direct result of these disperse particle properties. Therefore, the comprehensive multidimensional characterization of particle ensembles is a key task in any product design. However, the determination of complex property distributions is major challenge. We provide a broad overview of the current tools for multidimensional particle characterization. First, the mathematical handling of multidimensional (nD) property distribution is outlined as a necessary framework for the correct handling of nD particle size distributions (PSDs). Then, well-established techniques as well as recent developments with the potential to extract nD property distributions are reviewed. Ex situ imaging techniques like electron tomography or Raman spectroscopy with AFM co-localization, for instance, provide a resolution on the level of single particles but are limited in terms of sample statistics. A particular focus lies therefore on methods in the gas and the liquid phase, which provide multidimensional particle properties either directly or by a combination of one-dimensional techniques.

Niemöller et al. describe a bisulfite-free assay to assess epigenomics and genomics of single cells (epi-gSCAR). epi-gSCAR generates accurate and reproducible measurements of global DNA methylation and genetic variants at the single cell level, allowing for in-depth analyses of cell-to-cell heterogeneity.

Monitoring the humoral protective immune response and its durability after SARS-CoV-2 infections is essential for risk assessment of reinfections, the improvement of diagnostic methods and the evaluation of vaccine trials. We have analyzed neutralizing antibodies and IgG responses specific to different antigens, including the inactivated whole-virion of SARS-CoV-2, the spike subunit 1 protein and its receptor binding domain, as well as the nucleocapsid protein. We show the dynamic developments of the responses from the early convalescent stages up to 9 months post symptoms onset in follow-up samples from 57 COVID-19 patients with varying clinical severity. By correlating antibody signals to neutralizing titres, valid diagnostic markers for the estimation of neutralizing protection could be identified.

Acute promyelocytic leukemia (APL) is a subtype of myeloid leukemia characterized by differentiation block at the promyelocyte stage. Besides the presence of chromosomal rearrangement t(15;17), leading to the formation of PML-RARA (promyelocytic leukemia-retinoic acid receptor alpha) fusion, other genetic alterations have also been implicated in APL. Here, we performed comprehensive mutational analysis of primary and relapse APL to identify somatic alterations, which cooperate with PML-RARA in the pathogenesis of APL. We explored the mutational landscape using whole-exome (n=12) and subsequent targeted sequencing of 398 genes in 153 primary and 69 relapse APL. Both primary and relapse APL harbored an average of eight non-silent somatic mutations per exome. We observed recurrent alterations of FLT3, WT1, NRAS and KRAS in the newly diagnosed APL, whereas mutations in other genes commonly mutated in myeloid leukemia were rarely detected. The molecular signature of APL relapse was characterized by emergence of frequent mutations in PML and RARA genes. Our sequencing data also demonstrates incidence of loss-of-function mutations in previously unidentified genes, ARID1B and ARID1A, both of which encode for key components of the SWI/SNF complex. We show that knockdown of ARID1B in APL cell line, NB4, results in large-scale activation of gene expression and reduced in vitro differentiation potential.