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1.
Br J Haematol ; 2024 Apr 23.
Artículo en Inglés | MEDLINE | ID: mdl-38654616

RESUMEN

The potential prognostic influence of genetic aberrations on chronic lymphocytic leukaemia (CLL) can vary based on various factors, such as the immunoglobulin heavy variable (IGHV) status. We conducted an integrative analysis on genetic abnormalities identified through cytogenetics and targeted next-generation sequencing in 536 CLL patients receiving first-line chemo(immuno)therapies (CIT) as part of two prospective trials. We evaluated the prognostic implications of the main abnormalities, with specific attention to their relative impact according to IGHV status. In the entire cohort, unmutated (UM)-IGHV, complex karyotype, del(11q) and ATM mutations correlated significantly with shorter progression-free survival (PFS). Focusing on the subset of mutated IGHV (M-IGHV) patients, univariate analysis showed that complex karyotype, del(11q), SF3B1 and SAMHD1 mutations were associated with significant lower PFS. The prognostic influence varied based on the patient's IGHV status, as these abnormalities did not affect outcomes in the UM-IGHV subgroup. TP53 mutations had no significant impact on outcomes in the M-IGHV subgroup. Our findings highlight the diverse prognostic influence of genetic aberrations depending on the IGHV status in symptomatic CLL patients receiving first-line CIT. The prognosis of gene mutations and cytogenetic abnormalities needs to be investigated with a compartmentalized methodology, taking into account the IGVH status of patients receiving first-line BTK and/or BCL2 inhibitors.

2.
Ned Tijdschr Geneeskd ; 1682024 Apr 17.
Artículo en Holandés | MEDLINE | ID: mdl-38630094

RESUMEN

Shoulder dislocations remain the most frequent of joint dislocations, with anterior displacement of the humeral head being the direction of dislocation seen most often (97%). Recently, the Dutch clinical guideline on shoulder dislocations has been revised on the basis of predetermined bottlenecks in clinical practice. In this paper, the guideline is translated to clinical practice by means of two fictional cases, in which the novel recommendations are incorporated. The following topics were systematically assessed based on the best available scientific evidence: primary diagnostics, reduction techniques, painmedication/ sedation surrounding reduction and the need for physiotherapy, stabilization surgery and immobilization. Also, a best practice care pathway is advocated. Since scientific evidence is often inconclusive to provide undebatable therapeutic rules, the committee graded the available evidence and additionally used expert opinion to carefully draft recommendations. The paper concludes with an overview of all the recommendations stated in the updated multidisciplinary guideline.


Asunto(s)
Anestesia , Luxaciones Articulares , Luxación del Hombro , Humanos , Hombro , Luxación del Hombro/terapia , Etnicidad
3.
Nat Ecol Evol ; 8(4): 663-675, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38366132

RESUMEN

Climate change is altering the functioning of foundational ecosystems. While the direct effects of warming are expected to influence individual species, the indirect effects of warming on species interactions remain poorly understood. In marine systems, as tropical herbivores undergo poleward range expansion, they may change food web structure and alter the functioning of key habitats. While this process ('tropicalization') has been documented within declining kelp forests, we have a limited understanding of how this process might unfold across other systems. Here we use a network of sites spanning 23° of latitude to explore the effects of increased herbivory (simulated via leaf clipping) on the structure of a foundational marine plant (turtlegrass). By working across its geographic range, we also show how gradients in light, temperature and nutrients modified plant responses. We found that turtlegrass near its northern boundary was increasingly affected (reduced productivity) by herbivory and that this response was driven by latitudinal gradients in light (low insolation at high latitudes). By contrast, low-latitude meadows tolerated herbivory due to high insolation which enhanced plant carbohydrates. We show that as herbivores undergo range expansion, turtlegrass meadows at their northern limit display reduced resilience and may be under threat of ecological collapse.


Asunto(s)
Ecosistema , Herbivoria , Cadena Alimentaria , Bosques , Cambio Climático , Plantas
4.
Artículo en Inglés | MEDLINE | ID: mdl-38182028

RESUMEN

BACKGROUND: Primary glenohumeral osteoarthritis is associated with both excessive posterior humeral subluxation (PHS) and excessive glenoid retroversion in 40% of cases. These morphometric abnormalities are a particular issue because they may be responsible for a deterioration in long-term clinical and radiologic outcomes. The aim of this study was to perform a computed tomographic (CT) analysis of patients who underwent total shoulder arthroplasty (TSA) for primary osteoarthritis (OA) with B2-, B3-, or C-type glenoids in whom an attempt was made to correct for excessive glenoid retroversion and excessive posterior humeral subluxation intraoperatively. MATERIAL: We performed a retrospective, single-center study including 62 TSA patients with a preoperative PHS of the glenohumeral joint (31 men, 31 women, 70 ± 9 years) between January 2000 and January 2014. Glenoids were classified as B2 (32 cases), B3 (13 cases), or C (17 cases). Glenoid retroversion was corrected by anterior asymmetric reaming. Patients were reviewed for clinical and CT scan assessment with a mean follow-up of 8.3 years (minimum 5 years). At final follow-up, the CT images were reconstructed in the scapular plane. A PHS index >65% defined persistence. RESULTS: The revision-free rate was estimated at 93%. Correlation between PHS and retroversion was moderate preoperatively (ρ = 0.58) and strong at final follow-up (ρ = 0.73). Postoperative CT scans on average showed a surgical correction of PHS compared to preoperatively (79% vs. 65% respectively, P < .05) and retroversion (20° vs. 10° respectively, P < .05). At final follow-up, 25 of 62 patients had a persistence in the 2-dimensional (2D) model and 41 of 62 in the corrected 2D model. Persistence of PHS had no influence on clinical outcomes but did demonstrate a significantly higher glenoid loosening rate (20% vs. 59%, P < .05). CONCLUSION: Correlation between PHS and retroversion was moderate preoperatively and strengthened at long-term follow-up. Anterior asymmetric reaming allowed for a surgical improvement of both PHS and retroversion, but it was not sufficient to maintain a correction over time. Glenoid loosening was more frequent in case of PHS persistence but seemingly without clinical relevance.

5.
Lancet ; 403(10427): 645-656, 2024 Feb 17.
Artículo en Inglés | MEDLINE | ID: mdl-38278170

RESUMEN

BACKGROUND: CD55 deficiency with hyperactivation of complement, angiopathic thrombosis, and protein-losing enteropathy (CHAPLE) is an ultra-rare genetic disorder characterised by intestinal lymphatic damage, lymphangiectasia, and protein-losing enteropathy caused by overactivation of the complement system. We assessed the efficacy and safety of pozelimab, an antibody blocking complement component 5. METHODS: This open-label, single-arm, historically controlled, multicentre phase 2 and 3 study evaluated ten patients with CHAPLE disease. This study was conducted at three hospitals in Thailand, Türkiye, and the USA. Patients aged 1 year or older with a clinical diagnosis of CHAPLE disease and a CD55 loss-of-function variant identified by genetic analysis and confirmed by flow cytometry or western blot of CD55 from peripheral blood cells were eligible for this study. Patients received a single intravenous loading dose of pozelimab 30 mg per kg of bodyweight, followed by a once-per-week subcutaneous dose over the treatment period based on bodyweight at a concentration of 200 mg/mL as either a single injection (<40 kg bodyweight) or two injections (≥40 kg bodyweight). The primary endpoint was proportion of patients with serum albumin normalisation with an improvement in active clinical outcomes and no worsening in inactive clinical outcomes (frequency of problematic abdominal pain, bowel movement frequency, facial oedema severity, and peripheral oedema severity) at week 24 compared with baseline, assessed in the full analysis set. This study is registered with ClinicalTrials.gov (NCT04209634) and is active but not recruiting. FINDINGS: 11 patients were recruited between Jan 27, 2020, and May 12, 2021, ten of which were enrolled in the study and included in the analysis populations. The efficacy data corresponded to all patients completing the week 48 assessment and having at least 52 weeks of treatment exposure, and the safety data included an additional 90 days of follow-up and corresponded to all patients having at least 72 weeks of treatment. Patients were predominantly paediatric (with a median age of 8·5 years), and originated from Türkiye, Syria, Thailand, and Bolivia. Patients had markedly low weight-for-age and stature-for-age at baseline, and mean albumin at baseline was 2·2 g/dL, which was considerably less than the local laboratory reference range. After pozelimab treatment, all ten patients had serum albumin normalisation and improvement with no worsening in clinical outcomes. There was a complete inhibition of the total complement activity. Nine patients had adverse events; two were severe events, and one patient had an adverse event considered related to pozelimab. INTERPRETATION: Pozelimab inhibits complement overactivation and resolves the clinical and laboratory manifestations of CHAPLE disease. Pozelimab is the only currently approved therapeutic drug for patients with this life-threatening, ultra-rare condition. In patients with protein-losing enteropathy where known causes have been excluded, testing for a CD55 deficiency should be contemplated. A diagnosis of CHAPLE disease should lead to early consideration of treatment with pozelimab. FUNDING: Regeneron Pharmaceuticals and the Division of Intramural Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health.


Asunto(s)
Enteropatías Perdedoras de Proteínas , Trombosis , Niño , Humanos , Anticuerpos Monoclonales , Edema , Enteropatías Perdedoras de Proteínas/tratamiento farmacológico , Albúmina Sérica , Resultado del Tratamiento , Estudio Históricamente Controlado , Masculino , Femenino
6.
J Med Chem ; 66(15): 10617-10627, 2023 08 10.
Artículo en Inglés | MEDLINE | ID: mdl-37467168

RESUMEN

High hit rates from initial ligand-observed NMR screening can make it challenging to prioritize which hits to follow up, especially in cases where there are no available crystal structures of these hits bound to the target proteins or other strategies to provide affinity ranking. Here, we report a reproducible, accurate, and versatile quantitative ligand-observed NMR assay, which can determine Kd values of fragments in the affinity range of low µM to low mM using transverse relaxation rate R2 as the observable parameter. In this study, we examined the theory and proposed a mathematical formulation to obtain Kd values using non-linear regression analysis. We designed an assay format with automated sample preparation and simplified data analysis. Using tool compounds, we explored the assay reproducibility, accuracy, and detection limits. Finally, we used this assay to triage fragment hits, yielded from fragment screening against the CRBN/DDB1 complex.


Asunto(s)
Descubrimiento de Drogas , Bibliotecas de Moléculas Pequeñas , Ligandos , Reproducibilidad de los Resultados , Espectroscopía de Protones por Resonancia Magnética , Bibliotecas de Moléculas Pequeñas/química , Unión Proteica
7.
Chembiochem ; 24(23): e202300351, 2023 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-37418539

RESUMEN

Small molecules inducing protein degradation are important pharmacological tools to interrogate complex biology and are rapidly translating into clinical agents. However, to fully realise the potential of these molecules, selectivity remains a limiting challenge. Herein, we addressed the issue of selectivity in the design of CRL4CRBN recruiting PROteolysis TArgeting Chimeras (PROTACs). Thalidomide derivatives used to generate CRL4CRBN recruiting PROTACs have well described intrinsic monovalent degradation profiles by inducing the recruitment of neo-substrates, such as GSPT1, Ikaros and Aiolos. We leveraged structural insights from known CRL4CRBN neo-substrates to attenuate and indeed remove this monovalent degradation function in well-known CRL4CRBN molecular glues degraders, namely CC-885 and Pomalidomide. We then applied these design principles on a previously published BRD9 PROTAC (dBRD9-A) and generated an analogue with improved selectivity profile. Finally, we implemented a computational modelling pipeline to show that our degron blocking design does not impact PROTAC-induced ternary complex formation. We believe that the tools and principles presented in this work will be valuable to support the development of targeted protein degradation.


Asunto(s)
Ubiquitina-Proteína Ligasas , Ubiquitina-Proteína Ligasas/metabolismo , Proteolisis
8.
Phys Rev Lett ; 130(16): 161801, 2023 Apr 21.
Artículo en Inglés | MEDLINE | ID: mdl-37154647

RESUMEN

This Letter presents the first simultaneous measurement of the quasielasticlike neutrino-nucleus cross sections on C, water, Fe, Pb, and scintillator (hydrocarbon or CH) as a function of longitudinal and transverse muon momentum. The ratio of cross sections per nucleon between Pb and CH is always above unity and has a characteristic shape as a function of transverse muon momentum that evolves slowly as a function of longitudinal muon momentum. The ratio is constant versus longitudinal momentum within uncertainties above a longitudinal momentum of 4.5 GeV/c. The cross section ratios to CH for C, water, and Fe remain roughly constant with increasing longitudinal momentum, and the ratios between water or C to CH do not have any significant deviation from unity. Both the overall cross section level and the shape for Pb and Fe as a function of transverse muon momentum are not reproduced by current neutrino event generators. These measurements provide a direct test of nuclear effects in quasielasticlike interactions, which are major contributors to long-baseline neutrino oscillation data samples.

9.
J Med Chem ; 66(8): 5892-5906, 2023 04 27.
Artículo en Inglés | MEDLINE | ID: mdl-37026591

RESUMEN

B-cell lymphoma 6 (BCL6) is a transcriptional repressor and oncogenic driver of diffuse large B-cell lymphoma (DLBCL). Here, we report the optimization of our previously reported tricyclic quinolinone series for the inhibition of BCL6. We sought to improve the cellular potency and in vivo exposure of the non-degrading isomer, CCT373567, of our recently published degrader, CCT373566. The major limitation of our inhibitors was their high topological polar surface areas (TPSA), leading to increased efflux ratios. Reducing the molecular weight allowed us to remove polarity and decrease TPSA without considerably reducing solubility. Careful optimization of these properties, as guided by pharmacokinetic studies, led to the discovery of CCT374705, a potent inhibitor of BCL6 with a good in vivo profile. Modest in vivo efficacy was achieved in a lymphoma xenograft mouse model after oral dosing.


Asunto(s)
Linfoma de Células B Grandes Difuso , Quinolonas , Animales , Humanos , Ratones , Línea Celular Tumoral , Modelos Animales de Enfermedad , Linfoma de Células B Grandes Difuso/patología , Proteínas Proto-Oncogénicas c-bcl-6/química , Factores de Transcripción
10.
Cancers (Basel) ; 15(5)2023 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-36900299

RESUMEN

BACKGROUND: Despite that cytogenetic and molecular analysis of tumor cells can rapidly identify recurring molecular abnormalities, no personalized therapy is currently available in the setting of relapsed/refractory multiple myeloma (r/r MM). METHODS: MM-EP1 is a retrospective study aimed at comparing a personalized molecular-oriented (MO) versus a non-molecular-oriented (no-MO) approach in r/r MM. Actionable molecular targets and their associated therapies were the BRAF V600E mutation and BRAF inhibitors; t(11;14)(q13;q32) and BCL2 inhibitors; and t(4;14)(p16;q32) with FGFR3 fusion/rearrangements and FGFR3 inhibitors. RESULTS: One hundred three highly pretreated r/r MM patients with a median age of 67 years (range 44-85) were included. Seventeen (17%) patients were treated using an MO approach with BRAF inhibitors (vemurafenib or dabrafenib, n = 6), BCL2 inhibitor (venetoclax, n = 9), or FGFR3 inhibitor (erdafitinib, n = 2). Eighty-six (86%) patients received non-MO therapies. Overall response rate was 65% in MO patients versus 58% in the non-MO group (p = 0.053). Median PFS and OS were 9 and 6 months (HR = 0.96; CI95 = 0.51-1.78; p = 0.88) and 26 and 28 months (HR = 0.98; CI95 = 0.46-2.12; p = 0.98), respectively, in MO and no-MO patients. CONCLUSION: Despite the low number of patients treated with an MO approach, this study highlights the strengths and weakness of a molecular-targeted approach for the treatment of multiple myeloma. Widespread biomolecular techniques and improvement of precision medicine treatment algorithms could improve selection for precision medicine in myeloma.

11.
Nature ; 614(7946): 48-53, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-36725994

RESUMEN

Scattering of high energy particles from nucleons probes their structure, as was done in the experiments that established the non-zero size of the proton using electron beams1. The use of charged leptons as scattering probes enables measuring the distribution of electric charges, which is encoded in the vector form factors of the nucleon2. Scattering weakly interacting neutrinos gives the opportunity to measure both vector and axial vector form factors of the nucleon, providing an additional, complementary probe of their structure. The nucleon transition axial form factor, FA, can be measured from neutrino scattering from free nucleons, νµn → µ-p and [Formula: see text], as a function of the negative four-momentum transfer squared (Q2). Up to now, FA(Q2) has been extracted from the bound nucleons in neutrino-deuterium scattering3-9, which requires uncertain nuclear corrections10. Here we report the first high-statistics measurement, to our knowledge, of the [Formula: see text] cross-section from the hydrogen atom, using the plastic scintillator target of the MINERvA11 experiment, extracting FA from free proton targets and measuring the nucleon axial charge radius, rA, to be 0.73 ± 0.17 fm. The antineutrino-hydrogen scattering presented here can access the axial form factor without the need for nuclear theory corrections, and enables direct comparisons with the increasingly precise lattice quantum chromodynamics computations12-15. Finally, the tools developed for this analysis and the result presented are substantial advancements in our capabilities to understand the nucleon structure in the weak sector, and also help the current and future neutrino oscillation experiments16-20 to better constrain neutrino interaction models.

12.
Int J Emerg Med ; 16(1): 14, 2023 Feb 24.
Artículo en Inglés | MEDLINE | ID: mdl-36829126

RESUMEN

BACKGROUND: Biomechanical reduction techniques for shoulder dislocations have demonstrated high reduction success rates with a limited pain experience for the patient. We postulated that the combination of biomechanical reduction techniques with the shortest length of stay would also have the lowest pain experience and the highest first reduction success rate. METHODS: A randomized multicenter clinical trial was performed to compare different biomechanical reduction techniques in treating anterior shoulder dislocations without the use of invasive pain relief. Patients who were able to perform adduction of the arm were randomly assigned to Cunningham, the modified Milch, and the scapular manipulation technique. Those who were not able to do so were randomly assigned to modified Milch and the scapular manipulation technique. Primary outcomes were emergency department length of stay and pain experienced during the reduction process, measured by the numeric pain rating scale. Secondary outcomes were reduction time, reduction success, use of analgesics or sedatives, and complications. RESULTS: Three hundred eight patients were included, of whom 134 were in the adduction group. In both groups, no differences in emergency department length of stay and experienced pain were observed between the treatment arms. In the adduction group, the modified Milch technique had the highest first reduction success rates 52% (p = 0.016), within protocol 61% (p = 0.94), and with sedation in the ED 100% ( -). In the no-adduction group, the modified Milch was also the most successful primary reduction technique with 51% success (p = 0.040), within protocol 66% (p = 0.90), and with sedation in the ED 98% (p = 0.93). No complications were recorded in any of the techniques. CONCLUSION: A combination of biomechanical techniques resulted in a similar length of stay in the emergency department and showed similar pain scores with an overall high success rate of reduction. In both groups, the modified Milch had the highest first-reduction success rate. TRIAL REGISTRATION: Netherlands Trial Register NTR5839-1 April 2016. Ethical committee Noord-Holland with the CCMO-number NL54173.094.15.

13.
Am J Hematol ; 98(4): 645-657, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36606708

RESUMEN

Advances in molecular profiling of newly diagnosed diffuse large B-cell lymphoma (DLBCL) have recently refine genetic subgroups. Genetic subgroups remain undetermined at the time of relapse or refractory (RR) disease. This study aims to decipher genetic subgroups and search for prognostic molecular biomarkers in patients with RR-DLBCL. From 2015 to 2021, targeted next-generation sequencing analyses of germline-matched tumor samples and fresh tissue from RR-DLBCL patients were performed. Unsupervised clustering of somatic mutations was performed and correlations with patient outcome were sought. A number of 120 patients with RR-DLBCL were included in LNH-EP1 study and a molecular tumor landscape was successfully analyzed in 87% of patients (104/120 tumor samples). The median age was 67.5 years (range 27.4-87.4), median number of previous treatments was 2 (range 1-9). The most frequently mutated genes were TP53 (n = 53 mutations; 42% of samples), CREBBP (n = 39; 32%), BCL2 (n = 86; 31%), KMT2D (n = 39; 28%) and PIM1 (n = 54; 22%). Unsupervised clustering separated three genetic subgroups entitled BST (enriched in BCL2, SOCS1, and TNFRSF14 mutations); TKS (enriched in TP53, KMT2D, and STAT6 mutations); and PCM (enriched in PIM1, CD79B, and MYD88 mutations). Median overall survival (OS) was 11.0 (95% confidence interval [CI]: 8.1-12.6) months. OS was not significantly different between the three genetic subgroups. GNA13 mutant was significantly associated with an increased risk of death (hazard ratio: 6.6 [95% CI: 2.1-20.6]; p = .0011) and shorter OS (p = .0340). At the time of relapse or refractory disease, three genetic subgroups of DLBCL patients were delineated, which could help advance precision molecular medicine programs.


Asunto(s)
Linfoma de Células B Grandes Difuso , Recurrencia Local de Neoplasia , Humanos , Adulto , Persona de Mediana Edad , Anciano , Anciano de 80 o más Años , Pronóstico , Linfoma de Células B Grandes Difuso/diagnóstico , Mutación , Secuenciación de Nucleótidos de Alto Rendimiento , Proteínas Proto-Oncogénicas c-bcl-2/genética , Biomarcadores
14.
Sci Rep ; 12(1): 18633, 2022 11 03.
Artículo en Inglés | MEDLINE | ID: mdl-36329085

RESUMEN

By suppressing gene transcription through the recruitment of corepressor proteins, B-cell lymphoma 6 (BCL6) protein controls a transcriptional network required for the formation and maintenance of B-cell germinal centres. As BCL6 deregulation is implicated in the development of Diffuse Large B-Cell Lymphoma, we sought to discover novel small molecule inhibitors that disrupt the BCL6-corepressor protein-protein interaction (PPI). Here we report our hit finding and compound optimisation strategies, which provide insight into the multi-faceted orthogonal approaches that are needed to tackle this challenging PPI with small molecule inhibitors. Using a 1536-well plate fluorescence polarisation high throughput screen we identified multiple hit series, which were followed up by hit confirmation using a thermal shift assay, surface plasmon resonance and ligand-observed NMR. We determined X-ray structures of BCL6 bound to compounds from nine different series, enabling a structure-based drug design approach to improve their weak biochemical potency. We developed a time-resolved fluorescence energy transfer biochemical assay and a nano bioluminescence resonance energy transfer cellular assay to monitor cellular activity during compound optimisation. This workflow led to the discovery of novel inhibitors with respective biochemical and cellular potencies (IC50s) in the sub-micromolar and low micromolar range.


Asunto(s)
Linfoma de Células B Grandes Difuso , Humanos , Cristalografía por Rayos X , Proteínas Proto-Oncogénicas c-bcl-6/metabolismo , Linfoma de Células B Grandes Difuso/patología , Diseño de Fármacos , Ligandos
15.
Cell Rep Med ; 3(10): 100773, 2022 10 18.
Artículo en Inglés | MEDLINE | ID: mdl-36208628

RESUMEN

Natural killer (NK) cells are critical modulators of HIV transmission and disease. Recent evidence suggests a loss of NK cell cytotoxicity during aging, yet analysis of NK cell biology and aging in people with HIV (PWH) is lacking. Herein, we perform comprehensive analyses of people aging with and without HIV to determine age-related NK phenotypic changes. Utilizing high-dimensional flow cytometry, we analyze 30 immune-related proteins on peripheral NK cells from healthy donors, PWH with viral suppression, and viremic PWH. NK cell phenotypes are dynamic across aging but change significantly in HIV and on antiretroviral drug therapy (ART). NK cells in healthy aging show increasing ⍺4ß7 and decreasing CCR7 expression and a reverse phenomenon in PWH. These HIV-associated trafficking patterns could be due to NK cell recruitment to HIV reservoir formation in lymphoid tissue or failed mucosal signaling in the HIV-infected gut but appear to be tight delineators of age-related NK cell changes.


Asunto(s)
Infecciones por VIH , VIH-1 , Humanos , Receptores CCR7/metabolismo , Células Asesinas Naturales/metabolismo , Antirretrovirales/metabolismo , Infecciones por VIH/tratamiento farmacológico
16.
Clin Neurophysiol ; 140: 145-158, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-35780640

RESUMEN

OBJECTIVE: People with attention deficit and hyperactivity disorder (ADHD) present attentional and emotional deficits and show paradoxical qualities such as hyperfocus. Previous studies have reported errors, slowness, and reaction time (RT) variability using eye movements. This study aimed to explore the underlying mechanisms of ADHD further. METHODS: Thirty French children and teenagers, 15 with ADHD and 15 neurotypical (NT), underwent a saccadic eye movement task. We conducted conventional analysis (movement duration, precision, velocity, RT) and Bayesian analysis. RESULTS: Saccade duration and velocity failed to differentiate the two groups, whereas amplitude was higher in ADHD than in NT participants. Saccade RT and variability were higher in ADHD than in NT participants. In the Bayesian analysis, ADHD altered the main distribution of saccades and of early saccades but did not influence the express saccade triggering. CONCLUSIONS: ADHD disrupts two mechanisms of action: it reduces the gain of the decision signal, thus explaining slowness and variability; it quickens the decision process of early responses at the origin of short-latency but controlled movements. SIGNIFICANCE: These premises and their interconnections explain previous observations and support the striatal-frontal wiring of ADHD, thus explaining ADHD complexity in its negative and positive manifestations.


Asunto(s)
Trastorno por Déficit de Atención con Hiperactividad , Adolescente , Teorema de Bayes , Niño , Movimientos Oculares , Humanos , Tiempo de Reacción/fisiología , Movimientos Sacádicos
17.
J Med Chem ; 65(12): 8169-8190, 2022 06 23.
Artículo en Inglés | MEDLINE | ID: mdl-35657291

RESUMEN

To identify new chemical series with enhanced binding affinity to the BTB domain of B-cell lymphoma 6 protein, we targeted a subpocket adjacent to Val18. With no opportunities for strong polar interactions, we focused on attaining close shape complementarity by ring fusion onto our quinolinone lead series. Following exploration of different sized rings, we identified a conformationally restricted core which optimally filled the available space, leading to potent BCL6 inhibitors. Through X-ray structure-guided design, combined with efficient synthetic chemistry to make the resulting novel core structures, a >300-fold improvement in activity was obtained by the addition of seven heavy atoms.


Asunto(s)
Dominio BTB-POZ , Unión Proteica , Proteínas Proto-Oncogénicas c-bcl-6
18.
J Med Chem ; 65(12): 8191-8207, 2022 06 23.
Artículo en Inglés | MEDLINE | ID: mdl-35653645

RESUMEN

The transcriptional repressor BCL6 is an oncogenic driver found to be deregulated in lymphoid malignancies. Herein, we report the optimization of our previously reported benzimidazolone molecular glue-type degrader CCT369260 to CCT373566, a highly potent probe suitable for sustained depletion of BCL6 in vivo. We observed a sharp degradation SAR, where subtle structural changes conveyed the ability to induce degradation of BCL6. CCT373566 showed modest in vivo efficacy in a lymphoma xenograft mouse model following oral dosing.


Asunto(s)
Carcinogénesis , Regulación Neoplásica de la Expresión Génica , Animales , Humanos , Ratones , Proteínas Proto-Oncogénicas c-bcl-6/metabolismo
19.
JCI Insight ; 7(7)2022 04 08.
Artículo en Inglés | MEDLINE | ID: mdl-35393954

RESUMEN

Mutation of the TET2 DNA-hydroxymethylase has been associated with a number of immune pathologies. The disparity in phenotype and clinical presentation among these pathologies leads to questions regarding the role of TET2 mutation in promoting disease evolution in different immune cell types. Here we show that, in primary mast cells, Tet2 expression is induced in response to chronic and acute activation signals. In TET2-deficient mast cells, chronic activation via the oncogenic KITD816V allele associated with mastocytosis, selects for a specific epigenetic signature characterized by hypermethylated DNA regions (HMR) at immune response genes. H3K27ac and transcription factor binding is consistent with priming or more open chromatin at both HMR and non-HMR in proximity to immune genes in these cells, and this signature coincides with increased pathological inflammation signals. HMR are also associated with a subset of immune genes that are direct targets of TET2 and repressed in TET2-deficient cells. Repression of these genes results in immune tolerance to acute stimulation that can be rescued with vitamin C treatment or reiterated with a Tet inhibitor. Overall, our data support a model where TET2 plays a direct role in preventing immune tolerance in chronically activated mast cells, supporting TET2 as a viable target to reprogram the innate immune response for innovative therapies.


Asunto(s)
Proteínas de Unión al ADN , Dioxigenasas , Tolerancia Inmunológica , Mastocitos , Proteínas de Unión al ADN/metabolismo , Dioxigenasas/metabolismo , Mastocitos/inmunología , Proteínas Proto-Oncogénicas/genética , Proteínas Proto-Oncogénicas/metabolismo
20.
Infect Dis Model ; 7(2): 64-74, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35291224

RESUMEN

Modelling how a pandemic is spreading over time is a challenging issue. The new coronavirus disease called COVID-19 does not escape this rule as it has embraced over two hundred countries. As for previous pandemics, several studies have attempted to model the occurrence of cases caused by COVID-19. However, no study has succeeded in accurately modelling the impact of the infectious agent. Here we show that COVID-19 daily case distribution in humans obeys a Gamma law, which two new parameters can describe without any adjustment. Though the Gamma law has been exploited for nearly two centuries to describe the statistical distribution of spatial or temporal quantities, the goodness-of-fit rationale using two or three parameters has remained enigmatic. The new Gamma law approach we demonstrate here emerges from actual data and sheds light on the underlying mechanisms of the observed phenomenon. This finding has promising applicability in the epidemiological domain and in all disciplines involving branching systems, for which our Gamma law approach may bring a solution to hitherto unsolved problems.

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