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1.
Phys Rev Lett ; 132(16): 162501, 2024 Apr 19.
Artículo en Inglés | MEDLINE | ID: mdl-38701469

RESUMEN

The electromagnetic form factors of the proton and neutron encode information on the spatial structure of their charge and magnetization distributions. While measurements of the proton are relatively straightforward, the lack of a free neutron target makes measurements of the neutron's electromagnetic structure more challenging and more sensitive to experimental or model-dependent uncertainties. Various experiments have attempted to extract the neutron form factors from scattering from the neutron in deuterium, with different techniques providing different, and sometimes large, systematic uncertainties. We present results from a novel measurement of the neutron magnetic form factor using quasielastic scattering from the mirror nuclei ^{3}H and ^{3}He, where the nuclear effects are larger than for deuterium but expected to largely cancel in the cross-section ratios. We extracted values of the neutron magnetic form factor for low-to-modest momentum transfer, 0.6

2.
Eur J Pain ; 2024 Mar 25.
Artículo en Inglés | MEDLINE | ID: mdl-38528589

RESUMEN

BACKGROUND: Persistent postsurgical pain (PPSP) after lung cancer surgery is common and current definitions are based on evaluations at a single time point after surgery. Pain intensity and symptoms may however fluctuate and change over time, and be impacted by multiple and shifting factors. Studies of postoperative recovery patterns and transition from acute to chronic pain are needed for further investigation of preventive measures and treatments to modify unfavourable recovery paths. METHODS: In this explorative study, 85 patients undergoing surgery due to either presumptive or confirmed lung cancer reported pain intensities bi-monthly for 12 months. Pain trajectories during recovery were investigated, using group-based trajectory modelling. Associations with possible risk factors for PPSP, including clinical variables and anxiety and depression score (HADS), were also explored. RESULTS: A trajectory model containing three 12-month pain recovery groups was computed. One group without PPSP fully recovered (50%) within two to three months. Another group with mild-intensity PPSP followed a protracted recovery trajectory (37%), while incomplete recovery was observed in the last group (13%). Acute postoperative pain and younger age were associated with a less favourable recovery trajectory. More neuropathic pain symptoms were observed in patients with incomplete recovery. CONCLUSIONS: Three clinically relevant recovery trajectories were identified, based on comprehensive pain tracking. Higher acute postoperative pain intensity was associated with an unfavourable pain recovery trajectory. SIGNIFICANCE STATEMENT: Understanding the transition from acute to chronic postoperative pain and identifying preoperative risk factors is essential for the development of targeted treatments and the implementation of preventive measures. This study (1) identified distinct recovery trajectories based on frequent pain assessment follow-ups for 12 months after surgery and (2) evaluated risk factors for unfavourable postoperative pain recovery paths. Findings suggest that early higher postoperative pain intensity is associated with an unfavourable long-term recovery path.

4.
Exp Hematol ; 132: 104176, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38320689

RESUMEN

The overall survival rate of patients with T-cell acute lymphoblastic leukemia (T-ALL) is now 90%, although patients with relapsed T-ALL face poor prognosis. The ubiquitin-proteasome system maintains normal protein homeostasis, and aberrations in this pathway are associated with T-ALL. Here we demonstrate the in vitro and in vivo activity of ixazomib, a second-generation orally available, reversible, and selective proteasome inhibitor against pediatric T-ALL cell lines and patient-derived xenografts (PDXs) grown orthotopically in immunodeficient NOD.Cg-PrkdcscidIL2rgtm1Wjl/SzJAusb (NSG) mice. Ixazomib was highly potent in vitro, with half-maximal inhibitory concentration (IC50) values in the low nanomolar range. As a monotherapy, ixazomib significantly extended mouse event-free survival of five out of eight T-ALL PDXs in vivo.


Asunto(s)
Compuestos de Boro , Glicina/análogos & derivados , Leucemia-Linfoma Linfoblástico de Células T Precursoras , Humanos , Niño , Animales , Ratones , Leucemia-Linfoma Linfoblástico de Células T Precursoras/tratamiento farmacológico , Xenoinjertos , Inhibidores de Proteasoma/farmacología , Ratones Endogámicos NOD , Linfocitos T , Ratones SCID
5.
Heliyon ; 9(11): e22085, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-38053908

RESUMEN

Mutations within the IL7-R-JAK-STAT signaling pathway are important drivers of T-cell acute lymphoblastic leukemia (T-ALL). Here we describe the important steps required to generate retroviral particles for the stable expression of mutant JAK3 constructs that induce constitutive JAK/STAT signaling. These are subsequently used for the viral transduction of the IL-3 cytokine-dependent Ba/F3 cell line or murine hematopoietic stem and progenitor cells (HSPCs) for in vitro and in vivo modelling of cytokine-independent growth or leukemia initiation respectively.

6.
Haematologica ; 2023 Nov 09.
Artículo en Inglés | MEDLINE | ID: mdl-37941480

RESUMEN

T cell acute lymphoblastic leukemia (T-ALL) and T cell lymphoblastic lymphoma (T-LBL) are rare aggressive hematological malignancies. Current treatment consists of intensive chemotherapy, leading to 80% overall survival but are 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/TLBL patients for phosphorylated PDGFRB levels can serve as a biomarker for PDGFRB inhibition as a novel targeted therapeutic strategy in their treatment regimen.

8.
Radiother Oncol ; 188: 109887, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37659663

RESUMEN

PURPOSE/OBJECTIVE: Deep-inspiration breath-hold (DIBH) during radiotherapy may reduce dose to the lungs and heart compared to treatment in free breathing. However, intra-fractional target shifts between several breath-holds may decrease target coverage. We compared target shifts between four DIBHs at the planning-CT session with those measured on CBCT-scans obtained pre- and post-DIBH treatments. MATERIAL/METHODS: Twenty-nine lung cancer and nine lymphoma patients were treated in DIBH. An external gating block was used as surrogate for the DIBH-level with a window of 2 mm. Four DIBH CT-scans were acquired: one for planning (CTDIBH3) and three additional (CTDIBH1,2,4) to assess the intra-DIBH target shifts at scanning by registration to CTDIBH3. During treatment, pre-treatment (CBCTpre) and post-treatment (CBCTpost) scans were acquired. For each pair of CBCTpre/post, the target intra-DIBH shift was determined. For lung cancer, tumour (GTV-Tlung) and lymph nodes (GTV-Nlung) were analysed separately. Group mean (GM), systematic and random errors, and GM for the absolute maximum shifts (GMmax) were calculated for the shifts between CTDIBH1,2,3,4 and between CBCTpre/post. RESULTS: For GTV-Tlung, GMmax was larger at CBCT than CT in all directions. GMmax in cranio-caudal direction was 3.3 mm (CT)and 6.1 mm (CBCT). The standard deviations of the shifts in the left-right and cranio-caudal directions were larger at CBCT than CT. For GTV-Nlung and CTVlymphoma, no difference was found in GMmax or SD. CONCLUSION: Intra-DIBH shifts at planning-CT session are generally smaller than intra-DIBH shifts observed at CBCTpre/post and therefore underestimate the intra-fractional DIBH uncertainty during treatment. Lung tumours show larger intra-fractional variations than lymph nodes and lymphoma targets.

11.
Mov Ecol ; 10(1): 52, 2022 Nov 29.
Artículo en Inglés | MEDLINE | ID: mdl-36447280

RESUMEN

BACKGROUND: The movement extent of mammals is influenced by human-modified areas, which can affect population demographics. Understanding how human infrastructure influences movement at different life stages is important for wildlife management. This is true especially for large carnivores, due to their substantial space requirements and potential for conflict with humans. METHODS: We investigated human impact on movement and habitat selection by GPS-collared male brown bears (Ursus arctos) in two life stages (residents and dispersers) in central Sweden. We identified dispersers visually based on their GPS locations and used hidden Markov models to delineate dispersal events. We used integrated step selection analysis (iSSA) to infer movement and habitat selection at a local scale (availability defined by hourly relocations), and resource selection functions (RSFs) to infer habitat selection at a landscape scale (availability defined by the study area extent). RESULTS: Movement of residents on a local scale was facilitated by small forestry roads as they moved faster and selected areas closer to forestry roads, and they avoided areas closer to larger public roads and buildings on both scales. Dispersers were more ambivalent in their response to human infrastructure. Dispersers increased their speed closer to small forestry roads and larger public roads, did not exhibit selection for or against any road class, and avoided areas closer to buildings only at local scale. Dispersers did not select for any features on the landscape, which is likely explained by the novelty of the landscape or their naivety towards it. CONCLUSION: Our results show that movement in male brown bears is life stage-dependent and indicate that connectivity maps derived from movement data of dispersing animals may provide more numerous and more realistic pathways than those derived from resident animal data alone. This suggests that data from dispersing animals provide more realistic models for reconnecting populations and maintaining connectivity than if data were derived from resident animals alone.

12.
Public Health ; 213: 54-60, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36351328

RESUMEN

OBJECTIVES: Migraine and dementia, two major public health challenges, are associated, but more knowledge is needed to understand their relationship. Objectives of this study were to investigate 1) the association between non-self-reported measures of migraine and dementia, and whether dementia was associated with 2) migraine without aura (MO) and with aura (MA) in combination with migraine medication use, and 3) migraine severity operationalized as the number of migraine prescriptions. STUDY DESIGN: Matched cohort study. METHODS: National register data were obtained from individuals born between 1934 and 1958. Migraine cases (aged 25-58 years) were identified by migraine diagnoses and redeemed migraine medication. Migraine cases were matched with non-cases (N = 340,850) and date of diagnosis or medication redemption was defined as index year. Dementia was identified by dementia diagnoses and redeemed dementia medication. RESULTS: We observed a 1.46 (95% CI: 1.26-1.69) times higher dementia rate in individuals with a migraine diagnosis and a 0.86 (95% CI: 0.76-0.97) times lower rate when using migraine medication. We found the highest dementia rate among individuals with MA, who also used migraine medication (HR = 2.23; 95% CI: 1.19-4.17), and the lowest rate among individuals with MO, who also used medication (HR = 1.25; 95% CI: 0.75-2.10). The number of migraine medication prescriptions was not associated with dementia. CONCLUSIONS: Being registered with a migraine diagnosis was associated with a higher dementia rate, while use of prescribed migraine medication was not. The differences in the dementia rate among migraine cases identified via diagnoses versus medications warrants further investigation.


Asunto(s)
Demencia , Humanos , Estudios de Cohortes , Demencia/epidemiología
13.
Nature ; 609(7925): 41-45, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-36045235

RESUMEN

When protons and neutrons (nucleons) are bound into atomic nuclei, they are close enough to feel significant attraction, or repulsion, from the strong, short-distance part of the nucleon-nucleon interaction. These strong interactions lead to hard collisions between nucleons, generating pairs of highly energetic nucleons referred to as short-range correlations (SRCs). SRCs are an important but relatively poorly understood part of nuclear structure1-3, and mapping out the strength and the isospin structure (neutron-proton (np) versus proton-proton (pp) pairs) of these virtual excitations is thus critical input for modelling a range of nuclear, particle and astrophysics measurements3-5. Two-nucleon knockout or 'triple coincidence' reactions have been used to measure the relative contribution of np-SRCs and pp-SRCs by knocking out a proton from the SRC and detecting its partner nucleon (proton or neutron). These measurements6-8 have shown that SRCs are almost exclusively np pairs, but they had limited statistics and required large model-dependent final-state interaction corrections. Here we report on measurements using inclusive scattering from the mirror nuclei hydrogen-3 and helium-3 to extract the np/pp ratio of SRCs in systems with a mass number of three. We obtain a measure of the np/pp SRC ratio that is an order of magnitude more precise than previous experiments, and find a marked deviation from the near-total np dominance observed in heavy nuclei. This result implies an unexpected structure in the high-momentum wavefunction for hydrogen-3 and helium-3. Understanding these results will improve our understanding of the short-range part of the nucleon-nucleon interaction.

14.
Phys Rev Lett ; 129(4): 042501, 2022 Jul 22.
Artículo en Inglés | MEDLINE | ID: mdl-35939025

RESUMEN

We report a precise measurement of the parity-violating (PV) asymmetry A_{PV} in the elastic scattering of longitudinally polarized electrons from ^{48}Ca. We measure A_{PV}=2668±106(stat)±40(syst) parts per billion, leading to an extraction of the neutral weak form factor F_{W}(q=0.8733 fm^{-1})=0.1304±0.0052(stat)±0.0020(syst) and the charge minus the weak form factor F_{ch}-F_{W}=0.0277±0.0055. The resulting neutron skin thickness R_{n}-R_{p}=0.121±0.026(exp)±0.024(model) fm is relatively thin yet consistent with many model calculations. The combined CREX and PREX results will have implications for future energy density functional calculations and on the density dependence of the symmetry energy of nuclear matter.

15.
Phys Rev Lett ; 128(13): 132003, 2022 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-35426713

RESUMEN

The ratio of the nucleon F_{2} structure functions, F_{2}^{n}/F_{2}^{p}, is determined by the MARATHON experiment from measurements of deep inelastic scattering of electrons from ^{3}H and ^{3}He nuclei. The experiment was performed in the Hall A Facility of Jefferson Lab using two high-resolution spectrometers for electron detection, and a cryogenic target system which included a low-activity tritium cell. The data analysis used a novel technique exploiting the mirror symmetry of the two nuclei, which essentially eliminates many theoretical uncertainties in the extraction of the ratio. The results, which cover the Bjorken scaling variable range 0.19

16.
Science ; 376(6591): 383-390, 2022 04 22.
Artículo en Inglés | MEDLINE | ID: mdl-35446645

RESUMEN

Natural molecular machines contain protein components that undergo motion relative to each other. Designing such mechanically constrained nanoscale protein architectures with internal degrees of freedom is an outstanding challenge for computational protein design. Here we explore the de novo construction of protein machinery from designed axle and rotor components with internal cyclic or dihedral symmetry. We find that the axle-rotor systems assemble in vitro and in vivo as designed. Using cryo-electron microscopy, we find that these systems populate conformationally variable relative orientations reflecting the symmetry of the coupled components and the computationally designed interface energy landscape. These mechanical systems with internal degrees of freedom are a step toward the design of genetically encodable nanomachines.


Asunto(s)
Proteínas , Microscopía por Crioelectrón , Movimiento (Física) , Proteínas/genética
17.
Phys Rev Lett ; 128(14): 142501, 2022 Apr 08.
Artículo en Inglés | MEDLINE | ID: mdl-35476486

RESUMEN

We report precision determinations of the beam-normal single spin asymmetries (A_{n}) in the elastic scattering of 0.95 and 2.18 GeV electrons off ^{12}C, ^{40}Ca, ^{48}Ca, and ^{208}Pb at very forward angles where the most detailed theoretical calculations have been performed. The first measurements of A_{n} for ^{40}Ca and ^{48}Ca are found to be similar to that of ^{12}C, consistent with expectations and thus demonstrating the validity of theoretical calculations for nuclei with Z≤20. We also report A_{n} for ^{208}Pb at two new momentum transfers (Q^{2}) extending the previous measurement. Our new data confirm the surprising result previously reported, with all three data points showing significant disagreement with the results from the Z≤20 nuclei. These data confirm our basic understanding of the underlying dynamics that govern A_{n} for nuclei containing ≲50 nucleons, but point to the need for further investigation to understand the unusual A_{n} behavior discovered for scattering off ^{208}Pb.

19.
Phytopathology ; 112(9): 1917-1927, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35357158

RESUMEN

Understanding the level and type of resistance in potato varieties is relevant for integrating varietal resistance into the management of potato late blight. Accordingly, 54 potato varieties were tested for their level and type of resistance to late blight in 2019 and 2020 in Denmark. Spreader rows were artificially inoculated to ensure an even inoculum distribution in the trial. Disease severity was assessed once or twice per week. Cluster analysis (CA) was done based on the weighted mean absolute rate (WMAR), the relative area under the disease progress curve, the onset of disease (Xo), the severity of disease in the middle of the season, the time to reach 1% disease severity, the time to reach final disease severity, and the maximum disease severity. The resistance types were determined by comparing the tested varieties to Bintje (susceptible reference) for Xo and WMAR. The CA ranked the varieties as susceptible, moderately resistant, resistant, and very resistant based on their level of resistance. Except for a few varieties, the expressed resistance levels varied between the years. Several varieties that were susceptible in 2019 were moderately resistant in 2020. Also, the types of resistance that the varieties exhibited varied from year to year. In 2020, most varieties exhibited race-specific resistance, while in 2019 they mostly showed susceptible characteristics. The variation between years for the level and types of resistance of the varieties highlights the importance of regularly monitoring varietal resistance across time and space.


Asunto(s)
Phytophthora infestans , Solanum tuberosum , Enfermedades de las Plantas , Solanum tuberosum/genética
20.
Behav Ecol ; 33(1): 137-146, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35197809

RESUMEN

How and where a female selects an area to settle and breed is of central importance in dispersal and population ecology as it governs range expansion and gene flow. Social structure and organization have been shown to influence settlement decisions, but its importance in the settlement of large, solitary mammals is largely unknown. We investigate how the identity of overlapping conspecifics on the landscape, acquired during the maternal care period, influences the selection of settlement home ranges in a non-territorial, solitary mammal using location data of 56 female brown bears (Ursus arctos). We used a resource selection function to determine whether females' settlement behavior was influenced by the presence of their mother, related females, familiar females, and female population density. Hunting may remove mothers and result in socio-spatial changes before settlement. We compared overlap between settling females and their mother's concurrent or most recent home ranges to examine the settling female's response to the absence or presence of her mother on the landscape. We found that females selected settlement home ranges that overlapped their mother's home range, familiar females, that is, those they had previously overlapped with, and areas with higher density than their natal ranges. However, they did not select areas overlapping related females. We also found that when mothers were removed from the landscape, female offspring selected settlement home ranges with greater overlap of their mother's range, compared with mothers who were alive. Our results suggest that females are acquiring and using information about their social environment when making settlement decisions.

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