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Abstract Intrathecal synthesis of immunoglobulins (Igs) is a key hallmark of multiple sclerosis (MS). B cells are known to accumulate in the leptomeninges of MS patients and associate with pathology in the underlying cortex and a more severe disease course. However, the role of locally produced antibodies in MS brain pathology is poorly understood. Here, we quantified the protein levels of IgA, IgM, IgG and albumin in serum and cerebrospinal fluid (CSF) samples of 80 MS patients and 28 neurological controls to calculate Ig indices. In addition, we quantified presence of meningeal IgA+, IgM+ and IgG+ B cells in post-mortem brain tissue of 20 MS patients and 6 controls using immunostainings. IgM and IgG, but not IgA, indices were increased in CSF of MS patients compared to controls, with no observed differences between MS disease types. Both IgM and IgG indices correlated significantly with neurofilament light (NfL) levels in CSF, but not with clinical or radiological parameters of disease. Similarly, IgG+ and IgM+ B cells were increased in MS meninges compared to controls, whereas IgA+ B cells were not. Neuronal loss did not differ between sections with low or high IgA+, IgM+ and IgG+ B cells, but was increased in sections with high numbers of all CD19+ meningeal B cells. Similarly, high presence of CD19+ meningeal B cells and IgG+ meningeal B cells associated with increased microglial density in the underlying cortex. Taken together, intrathecal synthesis of IgG and IgM is elevated in MS, which corresponds to an increased number of IgG+ and IgM+ B cells in MS meninges. The significant correlation between intrathecal IgG and IgM production and NfL levels, and increased microglial activation in cortical areas adjacent to meningeal infiltrates with high levels of IgG+ B cells indicate a role for intrathecal IgM- and IgG-producing B cells in neuroinflammatory and degenerative processes in MS.

Abstract Quantum materials are often characterized by a marked sensitivity to minute changes in their physical environment, a property that can lead to new functionalities and thereby, to novel applications. One such key property is the magneto-elastoresistance (MER), the change in magnetoresistance (MR) of a metal induced by uniaxial strain. Understanding and modeling this response can prove challenging, particularly in systems with complex Fermi surfaces. Here, we present a thorough analysis of the MER in the nearly compensated Dirac nodal-line semi-metal ZrSiSe. Small amounts of strain (0.27%) lead to large changes (7%) in the MR. Subsequent analysis reveals that the MER response is driven primarily by a change in transport mobility that varies linearly with the applied strain. This study showcases how the effect of strain tuning on the electrical properties can be both qualitatively and quantitatively understood. A complementary Shubnikov-de Haas oscillation study sheds light on the root of this change in quantum mobility. Moreover, we unambiguously show that the Fermi surface consists of distinct electron and hole pockets revealed in quantum oscillation measurements originating from magnetic breakdown.

Abstract Background Currently, non- or minimally displaced distal radius fractures are treated by 3 to 5 weeks of cast immobilisation. Many patients with a distal radius fracture suffer from long-term functional restrictions, which might be related to stiffness due to cast immobilisation. Current literature indicates that 1 week of immobilisation might be safe; however, no level 1 evidence is available. This trial aims to compare 1 week of brace immobilisation with 3 weeks of cast immobilisation in patients with distal radius fractures that do not need reduction. Methods The aim of this trial is to evaluate the non-inferiority of 1 week of brace immobilisation in patients with non- or minimally displaced distal radius fractures. A two-armed single blinded multicentre randomised clinical trial will be conducted in three hospitals. Adult patients, between 18 and 50 years old, independent for activities of daily living, with a non- or minimally displaced distal radius fracture can be included in this study. The intervention group is treated with 1 week of brace immobilisation, and the control group with 3 weeks of cast immobilisation. Primary outcome is the patient-reported outcome measured by the Patient-Related Wrist Evaluation score (PRWE) at 6 months. Secondary outcomes are patient-reported outcome measured by the Quick Disabilities of the Arm, Shoulder and Hand score at 6 weeks and 6 months, PRWE at 6 weeks, range of motion, patient-reported pain score measured by VAS score, radiological outcome (dorsal/volar tilt, radial height, ulnar variance, presence of intra-articular step off), complications and cost-effectiveness measured by the EuroQol 5 Dimension questionnaire, Medical Consumption Questionnaire and Productivity Cost Questionnaire. Discussion This study will provide evidence on the optimal period of immobilisation in non-operatively treated displaced and reduced distal radius fractures. Both treatment options are accepted treatment protocols and both treatment options have a low risk of complications. Follow-up will be according to the current treatment protocol. This study will provide level 1 evidence on the optimal period and way of immobilisation for non- or minimally displaced distal radius fractures in adult patients. Trial registration ABR 81638 | NL81638.029.22 | www.toetsingonline.nl . 18th of October 2023

Background: Long-term outcome after a first venous thromboembolism (VTE) might be optimized by tailoring anticoagulant treatment duration on individual risks of recurrence and major bleeding. The L-TRRiP models (A–D) were previously developed in data from the Dutch Multiple Environment and Genetic Assessment of Risk Factors for Venous thrombosis study to predict VTE recurrence. Objectives: We aimed to externally validate models C and D using data from the United States Heart and Vascular Health (HVH) study. Methods: Data from participants with a first VTE who discontinued initial anticoagulant therapy were used to determine model performance. Missing data were imputed, and results were pooled according to Rubin’s rules. To determine discrimination, Harrell’s C-statistic was calculated. To assess calibration, the observed/expected (O/E) ratio was estimated, and calibration plots were created, in which we accounted for the competing risk of death. A stratified analysis based on age 70 years was performed. Results: Of 1430 participants from the HVH study, 187 experienced an unprovoked VTE recurrence during follow-up. The C-statistics of L-TRRIP models C and D were 0.62 (95% CI, 0.56-0.67) and 0.61 (95% CI, 0.55-0.67), respectively. The O/E ratio (1.00; 95% CI, 0.84-1.17 and 1.09; 95% CI, 0.91-1.27, respectively) and calibration plots indicated good calibration. The discrimination was similar between participants 70 years, whereas overall calibration was lower in participants

The superconducting transition-metal dichalcogenides 2H-NbSe_{2} and 2H-NbS_{2} are intensively studied on account of their unique electronic properties such as Ising superconductivity, found in multi- and monolayers, with upper critical fields beyond the Pauli limit. Even in bulk crystals, there are reports of multiband superconductivity and exotic states, such as the Fulde-Ferrell-Larkin-Ovchinnikov phase. In this work, we investigate the superconducting properties of 2H-NbS_{2} through a detailed high-field mapping of the phase diagram by means of magnetotransport and magnetostriction experiments. We compare the phase diagram between bulk crystals and a 6-nm-thick flake of 2H-NbS_{2} and find a drastically enhanced Maki parameter in the flake, signifying a change of the relevant pair-breaking mechanism from orbital to paramagnetic pair breaking, which we attribute to an effect of enhanced spin-orbit coupling.

Chaperone-Mediated Autophagy (CMA) is a major pathway of lysosomal proteolysis critical for cellular homoeostasis and metabolism. While extensively studied in mammals, CMA’s existence in fish has only been confirmed recently, offering exciting insights into its role in species facing environmental stress. Here, we shed light on the existence of 2 genes encoding the CMA-limiting factor Lamp2A (lysosomal associated membrane protein 2A) in rainbow trout (RT, Oncorhynchus mykiss), revealing distinct expression patterns across various tissues. Notably, RT lacking the most expressed Lamp2A exhibit profound hepatic proteome disturbances during acute nutritional stress, underscoring its pivotal role as a guardian of hepatic proteostasis. Building upon these findings, we introduce and validate the CMA activation score as a reliable indicator of CMA status, providing a valuable tool for detecting cellular stress in fish under environmental threats. Overall, our study offers new perspectives into understanding CMA from evolutionary and environmental contexts.

Abstract The kagome metals AV3Sb5 (A = K, Rb, Cs) present an ideal sandbox to study the interrelation between multiple coexisting correlated phases such as charge order and superconductivity. So far, no consensus on the microscopic nature of these states has been reached as the proposals struggle to explain all their exotic physical properties. Among these, field-switchable electric magneto-chiral anisotropy (eMChA) in CsV3Sb5 provides intriguing evidence for a rewindable electronic chirality, yet the other family members have not been likewise investigated. Here, we present a comparative study of magneto-chiral transport between CsV3Sb5 and KV3Sb5. Despite their similar electronic structure, KV3Sb5 displays negligible eMChA, if any, and with no field switchability. This is in stark contrast to the non-saturating eMChA in CsV3Sb5 even in high fields up to 35 T. In light of their similar band structures, the stark difference in eMChA suggests its origin in the correlated states. Clearly, the V kagome nets alone are not sufficient to describe the physics and the interactions with their environment are crucial in determining the nature of their low-temperature state.

AbstractTetramorium Mayr, 1855 is a worldwide distributed and hyperdiverse ant genus consisting of almost 600 taxa manifesting various life history strategies. Species of the Tetramorium inquilinum species-group represents one of the most extreme forms of parasitism and consist of degenerate workerless social parasites of several Tetramorium species. So far, its members have been recorded in the Palearctic from montane to alpine zones and reveal an interesting disjunction in host selection observed between eastern-Mediterranean and western-Mediterranean species. We describe a fifth member of the Tetramorium inquilinum species-group: Tetramorium albenae Salata, van Delft & Borowiec sp. n. The species morphologically differs from the remaining members of the group by the combination of the following characters: dense and erect pilosity of appendages and the whole body, smooth head sculpture, predominantly smooth anepisternum and katepisternum, lack of blunt teeth on propodeum, and presence of distinct carianae on the dorsolateral margins of the propodeum. Tetramorium albenae Salata, van Delft & Borowiec sp. n. was collected in a lowland olive grove, a site so far not associated with the Tetramorium inquilinum species-group, from a nest of Tetramorium kephalosi (a new host species for the group). The data presented in this paper provide new insights into the habitat preferences of the species of the Tetramorium inquilinum species-group and extend our knowledge on the potential host species of these parasites.http://zoobank.org/urn:lsid:zoobank.org:pub:62610BFE-7BF4-44E7-ADB5-3DD6A9B759C0

BAK and BAX execute intrinsic apoptosis by permeabilising the mitochondrial outer membrane. Their activity is regulated through interactions with pro-survival BCL-2 family proteins and with non-BCL-2 proteins including the mitochondrial channel protein VDAC2. VDAC2 is important for bringing both BAK and BAX to mitochondria where they execute their apoptotic function. Despite this important function in apoptosis, while interactions with pro-survival family members are well characterised and have culminated in the development of drugs that target these interfaces to induce cancer cell apoptosis, the interaction between BAK and VDAC2 remains largely undefined. Deep scanning mutagenesis coupled with cysteine linkage identified key residues in the interaction between BAK and VDAC2. Obstructive labelling of specific residues in the BH3 domain or hydrophobic groove of BAK disrupted this interaction. Conversely, mutating specific residues in a cytosol-exposed region of VDAC2 stabilised the interaction with BAK and inhibited BAK apoptotic activity. Thus, this VDAC2-BAK interaction site can potentially be targeted to either inhibit BAK-mediated apoptosis in scenarios where excessive apoptosis contributes to disease or to promote BAK-mediated apoptosis for cancer therapy.

Introduction Patients with a first venous thromboembolism (VTE) are at risk of recurrence. Recurrent VTE (rVTE) can be prevented by extended anticoagulant therapy, but this comes at the cost of an increased risk of bleeding. It is still uncertain whether patients with an intermediate recurrence risk or with a high recurrence and high bleeding risk will benefit from extended anticoagulant treatment, and whether a strategy where anticoagulant duration is tailored on the predicted risks of rVTE and bleeding can improve outcomes. The aim of the Leiden Thrombosis Recurrence Risk Prevention (L-TRRiP) study is to evaluate the outcomes of tailored duration of long-term anticoagulant treatment based on individualised assessment of rVTE and major bleeding risks.Methods and analysis The L-TRRiP study is a multicentre, open-label, cohort-based, randomised controlled trial, including patients with a first VTE. We classify the risk of rVTE and major bleeding using the L-TRRiP and VTE-BLEED scores, respectively. After 3 months of anticoagulant therapy, patients with a low rVTE risk will discontinue anticoagulant treatment, patients with a high rVTE and low bleeding risk will continue anticoagulant treatment, whereas all other patients will be randomised to continue or discontinue anticoagulant treatment. All patients will be followed up for at least 2 years. Inclusion will continue until the randomised group consists of 608 patients; we estimate to include 1600 patients in total. The primary outcome is the combined incidence of rVTE and major bleeding in the randomised group after 2 years of follow-up. Secondary outcomes include the incidence of rVTE and major bleeding, functional outcomes, quality of life and cost-effectiveness in all patients.Ethics and dissemination The protocol was approved by the Medical Research Ethics Committee Leiden-Den Haag-Delft. Results are expected in 2028 and will be disseminated through peer-reviewed journals and during (inter)national conferences.Trial registration number NCT06087952.

Abstract Background Outcomes for patients with relapsed acute lymphoblastic leukemia (ALL) are poor and there is a need for novel therapies to improve outcomes. Targeted inhibition of WEE1 with small-molecule inhibitor adavosertib (AZD1775) has emerged as a therapeutic strategy to sensitize cancer cells to DNA-damaging chemotherapeutics, particularly in the context of TP53-mutated tumors. However, WEE1 inhibition as a potential therapeutic strategy for patients with high-risk and relapsed ALL, including those with TP53 mutations, has not been definitively evaluated. Methods Anti-leukemic effects of adavosertib were investigated using a relapsed TP53 isogenic cell model system, primary patient, and patient-derived ALL samples (n = 27) in an ex vivo co-culture model system with bone marrow-derived mesenchymal stem cells. Combination effects with drugs currently used for relapsed ALL were quantified by Excess over Bliss analyses. Investigations for alterations of cell cycle and apoptosis as well as related proteins were examined by flow cytometry and Western blot, respectively. Results Our study demonstrates the potent anti-leukemic activity of the clinically advanced WEE1 inhibitor adavosertib in a large majority (n = 18/27) of high-risk and relapsed ALL specimens at lower than clinically attainable concentrations, independent of TP53 mutation status. We show that treatment with adavosertib results in S-phase disruption even in the absence of DNA-damaging agents and that premature mitotic entry is not a prerequisite for its anti-leukemic effects. We further demonstrate that WEE1 inhibition additively and synergistically enhances the anti-leukemic effects of multiple conventional chemotherapeutics used in the relapsed ALL treatment setting. Particularly, we demonstrate the highly synergistic and cytotoxic combination of adavosertib with the nucleoside analog cytarabine and provide mechanistic insights into the combinational activity, showing preferential engagement of apoptotic cell death over cell cycle arrest. Our findings strongly support in vivo interrogation of adavosertib with cytarabine in xenograft models of relapsed and high-risk ALL. Conclusions Together, our data emphasize the functional importance of WEE1 in relapsed ALL cells and show WEE1 as a promising p53-independent therapeutic target for the improved treatment of high-risk and relapsed ALL.

Not available.

The plant plasma membrane (PM) is an essential barrier between the cell and the external environment, controlling signal perception and transmission. It consists of an asymmetrical lipid bilayer made up of three different lipid classes: sphingolipids, sterols, and phospholipids. The glycosyl inositol phosphoryl ceramides (GIPCs), representing up to 40% of total sphingolipids, are assumed to be almost exclusively in the outer leaflet of the PM. However, their biological role and properties are poorly defined. In this study, we investigated the role of GIPCs in membrane organization. Because GIPCs are not commercially available, we developed a protocol to extract and isolate GIPC-enriched fractions from eudicots (cauliflower and tobacco) and monocots (leek and rice). Lipidomic analysis confirmed the presence of trihydroxylated long chain bases and 2-hydroxylated very long-chain fatty acids up to 26 carbon atoms. The glycan head groups of the GIPCs from monocots and dicots were analyzed by gas chromatograph-mass spectrometry, revealing different sugar moieties. Multiple biophysics tools, namely Langmuir monolayer, ζ-Potential, light scattering, neutron reflectivity, solid state 2H-NMR, and molecular modeling, were used to investigate the physical properties of the GIPCs, as well as their interaction with free and conjugated phytosterols. We showed that GIPCs increase the thickness and electronegativity of model membranes, interact differentially with the different phytosterols species, and regulate the gel-to-fluid phase transition during temperature variations. These results unveil the multiple roles played by GIPCs in the plant PM.

The plant plasma membrane (PM) is an essential barrier between the cell and the external environment, controlling signal perception and transmission. It consists of an asymmetrical lipid bilayer made up of three different lipid classes: sphingolipids, sterols, and phospholipids. The glycosyl inositol phosphoryl ceramides (GIPCs), representing up to 40% of total sphingolipids, are assumed to be almost exclusively in the outer leaflet of the PM. However, their biological role and properties are poorly defined. In this study, we investigated the role of GIPCs in membrane organization. Because GIPCs are not commercially available, we developed a protocol to extract and isolate GIPC-enriched fractions from eudicots (cauliflower and tobacco) and monocots (leek and rice). Lipidomic analysis confirmed the presence of trihydroxylated long chain bases and 2-hydroxylated very long-chain fatty acids up to 26 carbon atoms. The glycan head groups of the GIPCs from monocots and dicots were analyzed by gas chromatograph-mass spectrometry, revealing different sugar moieties. Multiple biophysics tools, namely Langmuir monolayer, ζ-Potential, light scattering, neutron reflectivity, solid state 2H-NMR, and molecular modeling, were used to investigate the physical properties of the GIPCs, as well as their interaction with free and conjugated phytosterols. We showed that GIPCs increase the thickness and electronegativity of model membranes, interact differentially with the different phytosterols species, and regulate the gel-to-fluid phase transition during temperature variations. These results unveil the multiple roles played by GIPCs in the plant PM.

In the original publication [...]

T-cell acute lymphoblastic leukemia (T-ALL) and T-cell lymphoblastic lymphoma (T-LBL) are rare aggressive hematologic malignancies. Current treatment consists of intensive chemotherapy leading to 80% overall survival but is associated with severe toxic side effects. Furthermore, 10-20% of patients still die from relapsed or refractory disease providing a strong rationale for more specific, targeted therapeutic strategies with less toxicities. Here, we report a novel MYH9::PDGFRB fusion in a T-LBL patient, and demonstrate that this fusion product is constitutively active and sufficient to drive oncogenic transformation in vitro and in vivo. Expanding our analysis more broadly across T-ALL, we found a T-ALL cell line and multiple patient-derived xenograft models with PDGFRB hyperactivation in the absence of a fusion, with high PDGFRB expression in TLX3 and HOXA T-ALL molecular subtypes. To target this PDGFRB hyperactivation, we evaluated the therapeutic effects of a selective PDGFRB inhibitor, CP-673451, both in vitro and in vivo and demonstrated sensitivity if the receptor is hyperactivated. Altogether, our work reveals that hyperactivation of PDGFRB is an oncogenic driver in T-ALL/T-LBL, and that screening T-ALL/T-LBL patients for phosphorylated PDGFRB levels can serve as a biomarker for PDGFRB inhibition as a novel targeted therapeutic strategy in their treatment regimen.

Purpose: Displaced distal radius fractures (DRFs) are treated by reduction and cast immobilization or by reduction and internal fixation. Both treatment options have been extensively researched in the literature, but still there is debate on the favorable treatment. Complications are infrequently described and if present, only mentioned as a minor detail. This study was initiated to provide insight into the rate of complications to add value to the discussion of the optimal treatment. Methods: A comprehensive search was conducted in three bibliographic databases. Suitable studies were randomized controlled trials (RCTs) and retrospective trials that compare reduction followed by cast immobilization or volar plating and reported on complications or suboptimal outcome. Results: Six studies, of which two RCTs and four retrospective studies, were included. In total, 467 patients with a DRF were analyzed. Wound healing problems, hardware-related complications, and removal of hardware occurred solely in patients who were treated by volar plating. Carpal tunnel syndrome, re-displacement, malunion, and severe stiffness occurred more often in the nonoperative group. No difference was found between both treatment options regarding tendon injuries, poor patient-reported outcome, distal radioulnar joint laxity-instability, and persistent pain after 1 year. The intensity of complications and patient-related factors were in general not analyzed in any of the included studies. Conclusion: Based on this systematic review on complications in the treatment of DRFs, there is no evident optimal treatment. The choice of treatment should depend on patient based, shared decision-making, taking the advantages and complications of both the nonoperative and operative treatment into account.

Plants subject to vegetative shade receive a low quantity of blue light (LB) and a low ratio of red to far-red light (LFLR). Here the authors show that while LB induces autophagy, LFLR leads to changes in lipid metabolism, and propose that these processes may contribute to shade avoidance responses.

Abstract Purpose Difficulty to recognize inflammatory rheumatic diseases (IRD) in a primary care setting leads to late referral to secondary care. An evidence-based digital referral algorithm can support early referral, yet implementation in daily practice only succeeds with support of end users. We aim to understand the context of implementing a digital referral algorithm and explore the potential barriers and facilitators to implementation. Methods This qualitative study comprised focus groups and an online survey. Focus groups were performed with patients from outpatient rheumatology clinics. Surveys were sent out to general practitioners and rheumatologists distributed over The Netherlands. The presented digital referral algorithm originates from the JOINT referral study. Thematic analysis was used with inductive and deductive approaches. Results In total 26 patients participated distributed over three focus groups, and 215 caregivers (104 rheumatologists, 111 general practitioners) filled out the survey. Both patients and caregivers endorse the need for early referral, and recognize the perceived benefit of the digital algorithm. Potential barriers include the complexity of currently included questions, and the outcome lacking information on what to do with no risk of IRD. In order for implementation to be successful, the inclusivity, accessibility, content and outcome of the algorithm are considered important themes. Conclusion Successful implementation of a digital referral algorithm needs a systematic multi-facetted approach, considering the barriers and facilitators for implementation as discussed. Since the majority of identified barriers and facilitators was overlapping between all stakeholders, findings from this study can reliably inform further decision strategies for successful implementation.