506 research outputs found
Annual medicago ecotypes from North West Libya
Nine Medicago species were represented in collections from 10 sites in North West Libya. This report outlines species distribution, maturity characteristics and coumestrol content of the ecotypes collected. Medicago laciniata was the most common species collected but there appeared to be a relationship to soil type amongst other species. M. truncatula predominated on heavier textured soils but M. tornata and M. littoralis were more frequent on sandy soils. The Libyan ecotypes were typically early flowering with a rapid rate of burr maturation. They contained low to moderate levels of the plant oestrogen coumestrol in dry stems. Evaluation work was carried out at Medina Research Station, 20 km south of Perth, Western Australia
Full automation of total metabolic tumor volume from FDG-PET/CT in DLBCL for baseline risk assessments
BACKGROUND: Current radiological assessments of (18)fluorodeoxyglucose-positron emission tomography (FDG-PET) imaging data in diffuse large B-cell lymphoma (DLBCL) can be time consuming, do not yield real-time information regarding disease burden and organ involvement, and hinder the use of FDG-PET to potentially limit the reliance on invasive procedures (e.g. bone marrow biopsy) for risk assessment. METHODS: Our aim is to enable real-time assessment of imaging-based risk factors at a large scale and we propose a fully automatic artificial intelligence (AI)-based tool to rapidly extract FDG-PET imaging metrics in DLBCL. On availability of a scan, in combination with clinical data, our approach generates clinically informative risk scores with minimal resource requirements. Overall, 1268 patients with previously untreated DLBCL from the phase III GOYA trial (NCT01287741) were included in the analysis (training: n = 846; hold-out: n = 422). RESULTS: Our AI-based model comprising imaging and clinical variables yielded a tangible prognostic improvement compared to clinical models without imaging metrics. We observed a risk increase for progression-free survival (PFS) with hazard ratios [HR] of 1.87 (95% CI: 1.31–2.67) vs 1.38 (95% CI: 0.98–1.96) (C-index: 0.59 vs 0.55), and a risk increase for overall survival (OS) (HR: 2.16 (95% CI: 1.37–3.40) vs 1.40 (95% CI: 0.90–2.17); C-index: 0.59 vs 0.55). The combined model defined a high-risk population with 35% and 42% increased odds of a 4-year PFS and OS event, respectively, versus the International Prognostic Index components alone. The method also identified a subpopulation with a 2-year Central Nervous System (CNS)-relapse probability of 17.1%. CONCLUSION: Our tool enables an enhanced risk stratification compared with IPI, and the results indicate that imaging can be used to improve the prediction of central nervous system relapse in DLBCL. These findings support integration of clinically informative AI-generated imaging metrics into clinical workflows to improve identification of high-risk DLBCL patients. TRIAL REGISTRATION: Registered clinicaltrials.gov number: NCT01287741. GRAPHICAL ABSTRACT: [Image: see text] SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1186/s40644-022-00476-0
Ubiquitination regulates PTEN nuclear import and tumor suppression
The PTEN tumor suppressor is frequently affected in cancer cells, and inherited PTEN mutation causes cancer-susceptibility conditions such as Cowden syndrome. PTEN acts as a plasma-membrane lipid-phosphatase antagonizing the phosphoinositide 3-kinase/AKT cell survival pathway. However, PTEN is also found in cell nuclei, but mechanism, function, and relevance of nuclear localization remain unclear. We show that nuclear PTEN is essential for tumor suppression and that PTEN nuclear import is mediated by its monoubiquitination. A lysine mutant of PTEN, K289E associated with Cowden syndrome, retains catalytic activity but fails to accumulate in nuclei of patient tissue due to an import defect. We identify this and another lysine residue as major monoubiquitination sites essential for PTEN import. While nuclear PTEN is stable, polyubiquitination leads to its degradation in the cytoplasm. Thus, we identify cancer-associated mutations of PTEN that target its posttranslational modification and demonstrate how a discrete molecular mechanism dictates tumor progression by differentiating between degradation and protection of PTEN
Role of Imaging in the Staging and Response Assessment of Lymphoma:Consensus of the International Conference on Malignant Lymphomas Imaging Working Group
This article comprises the consensus reached to update guidance on the use of PET-CT for staging and response assessment for 18F FDG-avid lymphomas in clinical practice and late-phase trials
Improved Efficacy of Tafasitamab plus Lenalidomide versus Systemic Therapies for Relapsed/Refractory DLBCL: RE-MIND2, an Observational Retrospective Matched Cohort Study
PURPOSE: In RE-MIND2 (NCT04697160), patient-level outcomes from the L-MIND study (NCT02399085) of tafasitamab plus lenalidomide were retrospectively compared with patient-level matched observational cohorts treated with National Cancer Care Network (NCCN)/European Society for Medical Oncology (ESMO)-listed systemic therapies for relapsed/refractory diffuse large B-cell lymphoma (DLBCL). PATIENTS AND METHODS: Data were collected from health records of eligible patients aged ≥18 years with histologically confirmed DLBCL who had received ≥2 systemic therapies for DLBCL (including ≥1 anti-CD20 therapy). Patients from L-MIND were matched with patients from the RE-MIND2 observational cohort using estimated propensity score-based 1:1 nearest-neighbor matching, balanced for nine covariates. The primary analysis compared tafasitamab plus lenalidomide with patients who received any systemic therapy for R/R DLBCL (pooled in one cohort) or bendamustine plus rituximab (BR) or rituximab plus gemcitabine and oxaliplatin (R-GemOx; as two distinct cohorts). The primary endpoint was overall survival (OS). Secondary endpoints included treatment response and time-to-event outcomes. RESULTS: In RE-MIND2, 3,454 patients were enrolled from 200 sites in North America, Europe, and Asia-Pacific. Strictly matched pairs of patients consisted of tafasitamab plus lenalidomide versus systemic therapies pooled (n = 76 pairs), versus BR (n = 75 pairs), and versus R-GemOx (n = 74 pairs). Significantly prolonged OS was reported with tafasitamab plus lenalidomide versus systemic pooled therapies [hazard ratios (HR): 0.55; P = 0.0068], BR (HR: 0.42; P < 0.0001), and R-GemOx (HR: 0.47; P = 0.0003). CONCLUSIONS: RE-MIND2, a retrospective observational study, met its primary endpoint, demonstrating prolonged OS with tafasitamab plus lenalidomide versus BR and R-GemOx. See related commentary by Cherng and Westin, p. 3908
RE-MIND2: comparative effectiveness of tafasitamab plus lenalidomide versus polatuzumab vedotin/bendamustine/rituximab (pola-BR), CAR-T therapies, and lenalidomide/rituximab (R2) based on real-world data in patients with relapsed/refractory diffuse large B-cell lymphoma
Abstract: RE-MIND2 (NCT04697160) compared patient outcomes from the L-MIND (NCT02399085) trial of tafasitamab+lenalidomide with those of patients treated with other therapies for relapsed/refractory (R/R) diffuse large B-cell lymphoma (DLBCL) who are autologous stem cell transplant ineligible. We present outcomes data for three pre-specified treatments not assessed in the primary analysis. Data were retrospectively collected from sites in North America, Europe, and the Asia Pacific region. Patients were aged ≥18 years with histologically confirmed DLBCL and received ≥2 systemic therapies for DLBCL (including ≥1 anti-CD20 therapy). Patients enrolled in the observational and L-MIND cohorts were matched using propensity score-based 1:1 nearest-neighbor matching, balanced for six covariates. Tafasitamab+lenalidomide was compared with polatuzumab vedotin+bendamustine+rituximab (pola-BR), rituximab+lenalidomide (R2), and CD19-chimeric antigen receptor T-cell (CAR-T) therapies. The primary endpoint was overall survival (OS). Secondary endpoints included treatment response and progression-free survival. From 200 sites, 3,454 patients were enrolled in the observational cohort. Strictly matched patient pairs consisted of tafasitamab+lenalidomide versus pola-BR (n = 24 pairs), versus R2 (n = 33 pairs), and versus CAR-T therapies (n = 37 pairs). A significant OS benefit was observed with tafasitamab+lenalidomide versus pola-BR (HR: 0.441; p = 0.034) and R2 (HR: 0.435; p = 0.012). Comparable OS was observed in tafasitamab+lenalidomide and CAR-T cohorts (HR: 0.953, p = 0.892). Tafasitamab+lenalidomide appeared to improve survival outcomes versus pola-BR and R2, and comparable outcomes were observed versus CAR-T. Although based on limited patient numbers, these data may help to contextualize emerging therapies for R/R DLBCL. Clinical trial registration: NCT04697160 (January 6, 2021
Patient-derived mutations within the N-terminal domains of p85α impact PTEN or Rab5 binding and regulation
The p85α protein regulates flux through the PI3K/PTEN signaling pathway, and also controls receptor trafficking via regulation of Rab-family GTPases. In this report, we determined the impact of several cancer patient-derived p85α mutations located within the N-terminal domains of p85α previously shown to bind PTEN and Rab5, and regulate their respective functions. One p85α mutation, L30F, significantly reduced the steady state binding to PTEN, yet enhanced the stimulation of PTEN lipid phosphatase activity. Three other p85α mutations (E137K, K288Q, E297K) also altered the regulation of PTEN catalytic activity. In contrast, many p85α mutations reduced the binding to Rab5 (L30F, I69L, I82F, I177N, E217K), and several impacted the GAP activity of p85α towards Rab5 (E137K, I177N, E217K, E297K). We determined the crystal structure of several of these p85α BH domain mutants (E137K, E217K, R262T E297K) for bovine p85α BH and found that the mutations did not alter the overall domain structure. Thus, several p85α mutations found in human cancers may deregulate PTEN and/or Rab5 regulated pathways to contribute to oncogenesis. We also engineered several experimental mutations within the p85α BH domain and identified L191 and V263 as important for both binding and regulation of Rab5 activit
Rapid and tunable method to temporally control gene editing based on conditional Cas9 stabilization
The CRISPR/Cas9 system is a powerful tool for studying gene function. Here, we describe a method that allows temporal control of CRISPR/Cas9 activity based on conditional Cas9 destabilization. We demonstrate that fusing an FKBP12-derived destabilizing domain to Cas9 (DD-Cas9) enables conditional Cas9 expression and temporal control of gene editing in the presence of an FKBP12 synthetic ligand. This system can be easily adapted to co-express, from the same promoter, DD-Cas9 with any other gene of interest without co-modulation of the latter. In particular, when co-expressed with inducible Cre-ERT2, our system enables parallel, independent manipulation of alleles targeted by Cas9 and traditional recombinase with single-cell specificity. We anticipate this platform will be used for the systematic characterization and identification of essential genes, as well as the investigation of the interactions between functional genes
Projective Hilbert space structures at exceptional points
A non-Hermitian complex symmetric 2x2 matrix toy model is used to study
projective Hilbert space structures in the vicinity of exceptional points
(EPs). The bi-orthogonal eigenvectors of a diagonalizable matrix are
Puiseux-expanded in terms of the root vectors at the EP. It is shown that the
apparent contradiction between the two incompatible normalization conditions
with finite and singular behavior in the EP-limit can be resolved by
projectively extending the original Hilbert space. The complementary
normalization conditions correspond then to two different affine charts of this
enlarged projective Hilbert space. Geometric phase and phase jump behavior are
analyzed and the usefulness of the phase rigidity as measure for the distance
to EP configurations is demonstrated. Finally, EP-related aspects of
PT-symmetrically extended Quantum Mechanics are discussed and a conjecture
concerning the quantum brachistochrone problem is formulated.Comment: 20 pages; discussion extended, refs added; bug correcte
Chest radiography practice in critically ill patients: a postal survey in the Netherlands
BACKGROUND: To ascertain current chest radiography practice in intensive care units (ICUs) in the Netherlands. METHODS: Postal survey: a questionnaire was sent to all ICUs with > 5 beds suitable for mechanical ventilation; pediatric ICUs were excluded. When an ICU performed daily-routine chest radiographs in any group of patients it was considered to be a "daily-routine chest radiography" ICU. RESULTS: From the number of ICUs responding, 63% practice a daily-routine strategy, in which chest radiographs are obtained on a daily basis without any specific reason. A daily-routine chest radiography strategy is practiced less frequently in university-affiliated ICUs (50%) as compared to other ICUs (68%), as well as in larger ICUs (> 20 beds, 50%) as compared to smaller ICUs (< 20 beds, 65%) (P > 0.05). Remarkably, physicians that practice a daily-routine strategy consider daily-routine radiographs helpful in guiding daily practice in less than 30% of all performed radiographs. Chest radiographs are considered essential for verification of the position of invasive devices (81%) and for diagnosing pneumothorax, pneumonia or acute respiratory distress syndrome (82%, 74% and 69%, respectively). On demand chest radiographs are obtained after introduction of thoracic drains, central venous lines and endotracheal tubes in 98%, 84% and 75% of responding ICUs, respectively. Chest films are also obtained in case of ventilatory deterioration (49% of responding ICUs), and after cardiopulmonary resuscitation (59%), tracheotomy (58%) and mini-tracheotomy (23%). CONCLUSION: There is notable lack of consensus on chest radiography practice in the Netherlands. This survey suggests that a large number of intensivists may doubt the value of daily-routine chest radiography, but still practice a daily-routine strategy
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