Executive functions and problem-solving-The contribution of inhibition, working memory, and cognitive flexibility to science problem-solving performance in elementary school students.

Previous research has shown that executive functions can contribute to successful problem-solving in preschool and elementary school children. However, most studies did not simultaneously assess the role of different specific aspects of executive functions. Therefore, the aim of our study was to investigate the individual contribution of inhibition, working memory, and cognitive flexibility to science problem-solving performance in elementary school children. A total of 478 children from first and second grades (Mage = 7.44 years) participated in our study. They performed a Go/No-go task (inhibition), a Corsi blocks backward task (working memory), a flexible item selection task (cognitive flexibility), and three science problem-solving tasks, including two gear turning tasks and one stabilization task. Structural equation modeling showed that working memory and cognitive flexibility individually contributed to problem-solving performance, whereas inhibition did not. We conclude that maintaining task requirements and dynamic object relations (working memory) and switching between different problem-solving phases (cognitive flexibility) are essential components of successful science problem-solving in elementary school children. Inhibitory processes may be more relevant in tasks involving a higher degree of interference at the task or response level.

Prospective Assessment of Treatment-Induced Liver Injury as a Cause of Diffuse Pathologic Hepatic Enhancement in Contrast-Enhanced Ultrasound.

OBJECTIVE: A hypo-enhancement of the liver in contrast-enhanced ultrasound (CEUS), pathologic one-minute hepatic enhancement (pOMHE), was recently observed in 70% of allogeneic hematopoietic stem cell transplantation patients with a high-risk profile for veno-occlusive disease (VOD). Whether pOMHE was a pre-clinical sign of VOD or an unspecific feature of liver damage secondary to intensive chemotherapy is unclear. METHODS: To investigate this, we studied CEUS patterns in patients receiving high-dose chemotherapy prior to autologous hematopoietic stem cell transplantation (auto-HSCT) or intensive induction therapy (IT) for the treatment of acute leukemia. From April 2020 to May 2021, patients undergoing auto-HSCT (n = 20) or acute leukemia patients prior to IT (n = 20) were included. All patients underwent a B-mode ultrasound and CEUS of the liver and spleen before treatment (d0) and on day 10 (d10) after therapy start. The one-minute hepatic enhancement was quantified. An optical density of liver enhancement less than 90% compared with the spleen was considered pathologic (pOMHE). Clinical and laboratory parameters used to assess a drug-induced liver injury (DILI) were documented. RESULTS: The OMHE was normal (d0 and d10) in 36 (90%) patients. After IT, 2 of 20 patients had a pOMHE. A DILI grade IV was diagnosed in one case and hyperfibrinolysis in the second case. In 2 of 20 (5%) auto-HSCT patients a pOMHE was observed at d10 without clinical symptoms. CONCLUSION: Chemotherapy-induced effects are not the cause of a pathologic liver enhancement. In contrast, severe DILI or hyperfibrinolysis can be associated with pOMHE.

Domain-specific knowledge and domain-general abilities in children's science problem-solving.

BACKGROUND: Problem-solving in early and middle childhood is of high relevance for cognitive developmental research and educational support. Previous research on science problem-solving has focussed on the process and strategies of children handling challenging tasks, but less on providing insights into the cognitive network that enables science problem-solving. AIMS: In this study, we aimed to investigate whether performance in science problem-solving is mainly determined by domain-specific rule knowledge, by domain-general cognitive abilities or both. METHODS: In our study, 215 6- to 8-year-old children completed a set of three domain-specific rule knowledge tasks and three corresponding problem-solving tasks that were content-coherent, as well as a vocabulary task, and a reasoning task. RESULTS: Correlational and regression analyses revealed a negligible impact of domain-specific rule knowledge on corresponding problem-solving tasks. In contrast, the associations between problem-solving performance in different domains and the associations between problem-solving performance and domain-general abilities (vocabulary and reasoning) were comparably strong. CONCLUSIONS: The findings suggest that science problem-solving in primary school children primarily relies on domain-general cognitive abilities. Implications of these findings are discussed with regard to cognitive theories and early science education.

Combined Focused Next-Generation Sequencing Assays to Guide Precision Oncology in Solid Tumors: A Retrospective Analysis from an Institutional Molecular Tumor Board.

BACKGROUND: Increasing knowledge of cancer biology and an expanding spectrum of molecularly targeted therapies provide the basis for precision oncology. Despite extensive gene diagnostics, previous reports indicate that less than 10% of patients benefit from this concept. METHODS: We retrospectively analyzed all patients referred to our center's Molecular Tumor Board (MTB) from 2018 to 2021. Molecular testing by next-generation sequencing (NGS) included a 67-gene panel for the detection of short-sequence variants and copy-number alterations, a 53- or 137-gene fusion panel and an ultra-low-coverage whole-genome sequencing for the detection of additional copy-number alterations outside the panel's target regions. Immunohistochemistry for microsatellite instability and PD-L1 expression complemented NGS. RESULTS: A total of 109 patients were referred to the MTB. In all, 78 patients received therapeutic proposals (70 based on NGS) and 33 were treated accordingly. Evaluable patients treated with MTB-recommended therapy (n = 30) had significantly longer progression-free survival than patients treated with other therapies (n = 17) (4.3 vs. 1.9 months, p = 0.0094). Seven patients treated with off-label regimens experienced major clinical benefits. CONCLUSION: The combined focused sequencing assays detected targetable alterations in the majority of patients. Patient benefits appeared to lie in the same range as with large-scale sequencing approaches.

The Nuclear Proteins TP73 and CUL4A Confer Resistance to Cytarabine by Induction of Translesion DNA Synthesis via Mono-ubiquitination of PCNA.

Resistance to cytarabine is a key problem in the treatment of acute myeloid leukemia (AML). To understand the molecular biology of resistance to cytarabine, a viability-based chemosensitizer screen was utilized. We screened synthetic lethal targets using 437 different small interfering RNAs (siRNAs) directed against factors involved in DNA repair mechanisms and cytarabine as the chemical compound. Three hits were identified: CUL4A, TP73, and RFC2. We show here that the ubiquitin ligase CULLIN 4A (CUL4A) and the tumor-suppressive transcription factor p73 contribute to drug resistance by modulating DNA damage response. P73 confers resistance to cytarabine therapy by transactivation of REV3L, encoding the catalytic subunit of translesion DNA polymerase ζ, and CUL4A probably by influencing proliferating cell nuclear antigen (PCNA) and the polymerase switch towards error-prone translesion DNA polymerases. Abrogation of the polymerase ζ by siRNA causes identical effects as siRNAs against CUL4A or TP73 and resensitizes cells towards cytarabine therapy in vitro. As CUL4A needs to be activated by neddylation to facilitate the degradation of several proteins including PCNA, we propose a novel explanation for the synergism between cytarabine and the neddylation inhibitor pevonedistat by inhibition of translesion synthesis. In keeping with this, in AML patients treated with cytarabine, we found high expression of CUL4A and TP73 to be associated with poor prognosis.

Idasanutlin plus cytarabine in relapsed or refractory acute myeloid leukemia: results of the MIRROS trial.

The phase 3 MIRROS (MDM2 antagonist Idasanutlin in Relapsed or Refractory acute myeloid leukemia [AML] for Overall Survival) trial (NCT02545283) evaluated the efficacy and safety of the small-molecule MDM2 antagonist idasanutlin plus cytarabine in patients with relapsed/refractory (R/R) AML. Adults (n = 447) with R/R AML whose disease relapsed or was refractory after ≤2 prior induction regimens as initial treatment or following salvage chemotherapy regimen, with Eastern Cooperative Oncology Group performance status ≤2 were enrolled regardless of TP53 mutation status and randomly assigned 2:1 to idasanutlin 300 mg or placebo orally twice daily plus cytarabine 1 g/m2 IV on days 1 to 5 of 28-day cycles. At primary analysis (cutoff, November 2019), 436 patients were enrolled, including 355 in the TP53 wild-type intention-to-treat (TP53WT-ITT) population. The primary endpoint, overall survival in the TP53WT-ITT population, was not met (median, 8.3 vs 9.1 months with idasanutlin-cytarabine vs placebo-cytarabine; stratified hazard ratio [HR], 1.08; 95% confidence interval [CI], 0.81-1.45; P = .58). The complete remission (CR) rate, a key secondary endpoint, was 20.3% vs 17.1% (odds ratio [OR], 1.23; 95% CI, 0.70-2.18). The overall response rate (ORR) was 38.8% vs 22.0% (OR, 2.25; 95% CI, 1.36-3.72). Common any-grade adverse events (≥10% incidence in any arm) were diarrhea (87.0% vs 32.9%), febrile neutropenia (52.8% vs 49.3%), and nausea (52.5% vs 31.5%). In summary, despite improved ORR, adding idasanutlin to cytarabine did not improve overall survival or CR rates in patients with R/R AML.

Cooling Nanorotors by Elliptic Coherent Scattering.

Simultaneously cooling the rotational and translational motion of nanoscale dielectrics into the quantum regime is an open task of great importance for sensing applications and quantum superposition tests. Here, we show that the six-dimensional ground state can be reached by coherent-scattering cooling with an elliptically polarized and shaped optical tweezer. We determine the cooling rates and steady-state occupations in a realistic setup and discuss applications for mechanical sensing and fundamental experiments.

Patient-Centeredness in Older Adults With Multimorbidity: Results of an Online Expert Delphi Study.

BACKGROUND AND OBJECTIVES: Older adults suffering from multimorbidity represent a priority target group for patient-centeredness (PC). We aimed to investigate the transferability of an existing integrated model of PC comprising 15 dimensions on the care of older adults with multimorbidity from an expert perspective. RESEARCH DESIGN AND METHODS: A total of 242 experts were invited to participate in a 2-round online Delphi study. In round 1, they were asked to (a) individually rate relevance and clarity of the dimensions, (b) add missing dimensions, and (c) prioritize the dimensions. In round 2, experts received results of round 1 and were asked to rerate their ratings. RESULTS: Forty-eight experts participated in round 1 and 39 in round 2. Ten dimensions were rated as sufficiently relevant and clear, including one new dimension ("prognosis and life expectancy, burden of treatment"). Four dimensions were rated as relevant but insufficiently clear. One dimension failed to reach our validation threshold on both criteria. The 5 dimensions rated as most important were: "patient as a unique person," "clinician-patient communication," "patient involvement in care," "physical, cognitive, and emotional support," and "involvement of family and friends." DISCUSSION AND IMPLICATIONS: The experts' ratings were higher regarding relevance than regarding clarity, which emphasizes the still existing conceptual uncertainty of PC. Our results give further directions regarding the operationalization of PC in older adults with multimorbidity, which is essential for its implementation in routine care. Further refined using focus groups with geriatric patients, our adapted model serves as a basis for a systematic review of assessment instruments.

Neuroligin-2 dependent conformational activation of collybistin reconstituted in supported hybrid membranes.

The assembly of the postsynaptic transmitter sensing machinery at inhibitory nerve cell synapses requires the intimate interplay between cell adhesion proteins, scaffold and adaptor proteins, and γ-aminobutyric acid (GABA) or glycine receptors. We developed an in vitro membrane system to reconstitute this process, to identify the essential protein components, and to define their mechanism of action, with a specific focus on the mechanism by which the cytosolic C terminus of the synaptic cell adhesion protein Neuroligin-2 alters the conformation of the adaptor protein Collybistin-2 and thereby controls Collybistin-2-interactions with phosphoinositides (PtdInsPs) in the plasma membrane. Supported hybrid membranes doped with different PtdInsPs and 1,2-dioleoyl-sn-glycero-3-{[N-(5-amino-1-carboxypentyl)iminodiacetic acid]succinyl} nickel salt (DGS-NTA(Ni)) to allow for the specific adsorption of the His6-tagged intracellular domain of Neuroligin-2 (His-cytNL2) were prepared on hydrophobically functionalized silicon dioxide substrates via vesicle spreading. Two different collybistin variants, the WT protein (CB2SH3) and a mutant that adopts an intrinsically 'open' and activated conformation (CB2SH3/W24A-E262A), were bound to supported membranes in the absence or presence of His-cytNL2. The corresponding binding data, obtained by reflectometric interference spectroscopy, show that the interaction of the C terminus of Neuroligin-2 with Collybistin-2 induces a conformational change in Collybistin-2 that promotes its interaction with distinct membrane PtdInsPs.

Pathologic Hepatic Contrast-Enhanced Ultrasound Pattern in Patients Undergoing Allogeneic Stem Cell Transplantation.

Veno-occlusive disease (VOD) is a severe complication of allogeneic stem cell transplantation (allo-SCT). Its diagnosis is difficult, and ultrasound (US) has not been proven to be of additional diagnostic value. In the work described here, we prospectively analyzed the hepatic contrast-enhanced ultrasound (CEUS) pattern before and after allo-SCT and correlated these results with the pre-allo-SCT VOD risk factors, clinical VOD findings and conventional US findings. Thirty consecutive patients who underwent allo-SCT and had at least one VOD risk factor were studied. B-Mode US and CEUS were longitudinally performed at defined time points before and after allo-SCT. The 1-min hepatic enhancement (OMHE) in CEUS was standardized to splenic enhancement and quantified using optical density (OD) measurement software. A hypo-OMHE was arbitrarily defined as pathologic (pOMHE) if the OD of the liver was less than 90% compared with the mean splenic OD. Twenty-one patients (70%) had a pOMHE, the occurrence of which peaked at day 10 after allo-SCT. The number of pre-treatment VOD risk factors significantly differed between the pathologic and non-pathologic OD groups. Together, patients undergoing allo-SCT frequently exhibit a pathologic hepatic CEUS pattern, which can be quantified by OD measurement and is suggestive of pre-clinical VOD or other hepatic pathologies.

Leaflet-Dependent Distribution of PtdIns[4,5]P2 in Supported Model Membranes.

Supported planar lipid bilayers (SLBs) prepared by spreading of unilamellar vesicles on hydrophilic substrates such as silicon dioxide are frequently used to investigate lipid-protein interactions by means of surface-sensitive methods. In recent years, the receptor lipid phosphatidylinositol-4,5-bisphosphate (PtdIns[4,5]P2) became particularly important as a significant number of proteins bind to this lipid at the inner leaflet of the plasma membrane. Here, we investigated how the lipid PtdIns[4,5]P2 distributes between the two leaflets of an SLB on SiO2 surfaces. We prepared SLBs on SiO2 by spreading small unilamellar vesicles and quantified the adsorption of PtdIns[4,5]P2 binding proteins providing information about the accessibility of PtdIns[4,5]P2. We compared protein binding to PtdIns[4,5]P2 in SLBs with that in lipid monolayers on a 1,1,1-trimethyl-N-(trimethylsilyl)silanamine-functionalized SiO2 surface using reflectometric interference spectroscopy and atomic force microscopy. Our results clearly demonstrate that the accessibility of PtdIns[4,5]P2 for protein binding is reduced in SLBs compared to that in supported hybrid membranes, which is discussed in terms of PtdIns[4,5]P2 distribution in the two leaflets of SLBs.

Cell-Substrate Dynamics of the Epithelial-to-Mesenchymal Transition.

The biological process of the epithelial-to-mesenchymal transition (EMT) allows epithelial cells to enhance their migratory and invasive behavior and plays a key role in embryogenesis, fibrosis, wound healing, and metastasis. Among the multiple biochemical changes from an epithelial to a mesenchymal phenotype, the alteration of cellular dynamics in cell-cell as well as cell-substrate contacts is crucial. To determine these variations over the whole time scale of the EMT, we measure the cell-substrate distance of epithelial NMuMG cells during EMT using our newly established metal-induced energy transfer (MIET) microscopy, which allows one to achieve nanometer axial resolution. We show that, in the very first hours of the transition, the cell-substrate distance increases substantially, but later in the process after reaching the mesenchymal state, this distance is reduced again to the level of untreated cells. These findings relate to a change in the number of adhesion points and will help to better understand remodeling processes associated with wound healing, embryonic development, cancer progression, or tissue regeneration.

Palliative care for patients with heart failure: facilitators and barriers - a cross sectional survey of German health care professionals.

BACKGROUND: Compared to patients with cancer, heart failure patients are seldom candidates for palliative care. Numerous studies have investigated reasons why heart failure patients do not receive palliative care; however, none of these studies have ever evaluated the situation in the German health care setting. This study aims to identify German healthcare providers' (HCP) perception of barriers and facilitators to palliative care of patients with chronic heart failure. METHODS: We conducted an online-survey with 315 nurses and physicians of different medical disciplines. RESULTS: Even though heart failure patients' need of palliative care and its advantages has been recognized, HCP see potential for development and improvement. A lack of knowledge about the content and measures of palliative care, poor communication and unclear responsibilities between medical disciplines, difficulties to determine the right time to initiate palliative care, and the feeling not to be prepared to discuss end-of-life issues with the patient has been identified as barriers. Further, HCP believe that patients and relatives do not possess adequate knowledge about the disease and its progression and are therefore unprepared in asking questions regarding palliative care. They rather tend to demand everything possible to be done in order prolong life, and are reluctant to accept that life is limited. Overall, HCP perceive that dying is a taboo subject within our society placing palliative care on the same level as assisted dying. In addition, results indicate that HCP have an inappropriate notion of ideal medicine fearing to lose patient and are worried about the appropriateness of PC remuneration. CONCLUSIONS: In order to overcome the described barriers, HCP, patients, and relatives need to be educated in palliative care. Information and education encompassing the aim, content and measures of palliative care needs to be provided for all parties in order to optimize patient care, to foster communication between healthcare professionals, patients, and relatives, and to overcome perceived barriers. TRIAL REGISTRATION: DRKS00007119.

Mode of Ezrin-Membrane Interaction as a Function of PIP2 Binding and Pseudophosphorylation.

Ezrin, a protein of the ezrin, radixin, moesin (ERM) family, provides a regulated linkage between the plasma membrane and the cytoskeleton. The hallmark of this linkage is the activation of ezrin by phosphatidylinositol-4,5-bisphosphate (PIP2) binding and a threonine phosphorylation at position 567. To analyze the influence of these activating factors on the organization of ezrin on lipid membranes and the proposed concomitant oligomer-monomer transition, we made use of supported lipid bilayers in conjunction with atomic force microscopy and fluorescence microscopy. Bilayers doped with either PIP2 as the natural receptor lipid of ezrin or a Ni-nitrilotriacetic acid-equipped lipid to bind the proteins via their His6-tags to the lipid membrane were used to bind two different ezrin variants: ezrin wild-type and ezrin T567D mimicking the phosphorylated state. Using a combination of reflectometric interference spectroscopy, atomic force microscopy, and Förster resonance energy transfer experiments, we show that only the ezrin T567D mutant, upon binding to PIP2-containing bilayers, undergoes a remarkable conformational change, which we attribute to an opening of the conformation resulting in monomeric protein on the lipid bilayer.

Specificity of Collybistin-Phosphoinositide Interactions: IMPACT OF THE INDIVIDUAL PROTEIN DOMAINS.

The regulatory protein collybistin (CB) recruits the receptor-scaffolding protein gephyrin to mammalian inhibitory glycinergic and GABAergic postsynaptic membranes in nerve cells. CB is tethered to the membrane via phosphoinositides. We developed an in vitro assay based on solid-supported 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine membranes doped with different phosphoinositides on silicon/silicon dioxide substrates to quantify the binding of various CB2 constructs using reflectometric interference spectroscopy. Based on adsorption isotherms, we obtained dissociation constants and binding capacities of the membranes. Our results show that full-length CB2 harboring the N-terminal Src homology 3 (SH3) domain (CB2SH3+) adopts a closed and autoinhibited conformation that largely prevents membrane binding. This autoinhibition is relieved upon introduction of the W24A/E262A mutation, which conformationally "opens" CB2SH3+ and allows the pleckstrin homology domain to properly bind lipids depending on the phosphoinositide species with a preference for phosphatidylinositol 3-monophosphate and phosphatidylinositol 4-monophosphate. This type of membrane tethering under the control of the release of the SH3 domain of CB is essential for regulating gephyrin clustering.

Monitoring the dynamics of clonal tumour evolution in vivo using secreted luciferases.

Tumours are heterogeneous cell populations that undergo clonal evolution during tumour progression, metastasis and response to therapy. Short hairpin RNAs (shRNAs) generate stable loss-of-function phenotypes and are versatile experimental tools to explore the contribution of individual genetic alterations to clonal evolution. In these experiments tumour cells carrying shRNAs are commonly tracked with fluorescent reporters. While this works well for cell culture studies and leukaemia mouse models, fluorescent reporters are poorly suited for animals with solid tumours--the most common tumour types in cancer patients. Here we develop a toolkit that uses secreted luciferases to track the fate of two different shRNA-expressing tumour cell clones competitively, both in vitro and in vivo. We demonstrate that secreted luciferase activities can be measured robustly in the blood stream of tumour-bearing mice to accurately quantify, in a minimally invasive manner, the dynamic evolution of two genetically distinct tumour subclones in preclinical mouse models of tumour development, metastasis and therapy.