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CRISPR-Cas nucleoproteins target foreign DNA via base pairing with a crRNA. However, a quantitative description of protein binding and nuclease activation at off-target DNA sequences remains elusive. Here, we describe a chip-hybridized association-mapping platform (CHAMP) that repurposes next-generation sequencing chips to simultaneously measure the interactions between proteins and â¼107 unique DNA sequences. Using CHAMP, we provide the first comprehensive survey of DNA recognition by a type I-E CRISPR-Cas (Cascade) complex and Cas3 nuclease. Analysis of mutated target sequences and human genomic DNA reveal that Cascade recognizes an extended protospacer adjacent motif (PAM). Cascade recognizes DNA with a surprising 3-nt periodicity. The identity of the PAM and the PAM-proximal nucleotides control Cas3 recruitment by releasing the Cse1 subunit. These findings are used to develop a model for the biophysical constraints governing off-target DNA binding. CHAMP provides a framework for high-throughput, quantitative analysis of protein-DNA interactions on synthetic and genomic DNA. PAPERCLIP.
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Proteínas de Ligação a DNA/análise , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Ligação Proteica , Análise de Sequência de DNA/métodos , Sistemas CRISPR-Cas , Ensaio de Desvio de Mobilidade Eletroforética , Microscopia de Fluorescência , Motivos de NucleotídeosRESUMO
Many cratonic continental fragments dispersed during the rifting and break-up of Gondwana are bound by steep topographic landforms known as 'great escarpments'1-4, which rim elevated plateaus in the craton interior5,6. In terms of formation, escarpments and plateaus are traditionally considered distinct owing to their spatial separation, occasionally spanning more than a thousand kilometres. Here we integrate geological observations, statistical analysis, geodynamic simulations and landscape-evolution models to develop a physical model that mechanistically links both phenomena to continental rifting. Escarpments primarily initiate at rift-border faults and slowly retreat at about 1 km Myr-1 through headward erosion. Simultaneously, rifting generates convective instabilities in the mantle7-10 that migrate cratonward at a faster rate of about 15-20 km Myr-1 along the lithospheric root, progressively removing cratonic keels11, driving isostatic uplift of craton interiors and forming a stable, elevated plateau. This process forces a synchronized wave of denudation, documented in thermochronology studies, which persists for tens of millions of years and migrates across the craton at a comparable or slower pace. We interpret the observed sequence of rifting, escarpment formation and exhumation of craton interiors as an evolving record of geodynamic mantle processes tied to continental break-up, upending the prevailing notion of cratons as geologically stable terrains.
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Kimberlites are volatile-rich, occasionally diamond-bearing magmas that have erupted explosively at Earth's surface in the geologic past1-3. These enigmatic magmas, originating from depths exceeding 150 km in Earth's mantle1, occur in stable cratons and in pulses broadly synchronous with supercontinent cyclicity4. Whether their mobilization is driven by mantle plumes5 or by mechanical weakening of cratonic lithosphere4,6 remains unclear. Here we show that most kimberlites spanning the past billion years erupted about 30 million years (Myr) after continental breakup, suggesting an association with rifting processes. Our dynamical and analytical models show that physically steep lithosphere-asthenosphere boundaries (LABs) formed during rifting generate convective instabilities in the asthenosphere that slowly migrate many hundreds to thousands of kilometres inboard of rift zones. These instabilities endure many tens of millions of years after continental breakup and destabilize the basal tens of kilometres of the cratonic lithosphere, or keel. Displaced keel is replaced by a hot, upwelling mixture of asthenosphere and recycled volatile-rich keel in the return flow, causing decompressional partial melting. Our calculations show that this process can generate small-volume, low-degree, volatile-rich melts, closely matching the characteristics expected of kimberlites1-3. Together, these results provide a quantitative and mechanistic link between kimberlite episodicity and supercontinent cycles through progressive disruption of cratonic keels.
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Type 2 lymphocytes promote both physiologic tissue remodeling and allergic pathology, yet their physical tissue niches are poorly described. Here, we used quantitative imaging to define the tissue niches of group 2 innate lymphoid cells (ILC2s), which are critical instigators of type 2 immunity. We identified a dominant adventitial niche around lung bronchi and larger vessels in multiple tissues, where ILC2s localized with subsets of dendritic and regulatory T cells. However, ILC2s were most intimately associated with adventitial stromal cells (ASCs), a mesenchymal fibroblast-like subset that expresses interleukin-33 (IL-33) and thymic stromal lymphopoietin (TSLP). In vitro, ASCs produced TSLP that supported ILC2 accumulation and activation. ILC2s and IL-13 drove reciprocal ASC expansion and IL-33 expression. During helminth infection, ASC depletion impaired lung ILC2 and Th2 cell accumulation and function, which are in part dependent on ASC-derived IL-33. These data indicate that adventitial niches are conserved sites where ASCs regulate type 2 lymphocyte expansion and function.
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Imunidade Inata/imunologia , Linfócitos/imunologia , Células Estromais/imunologia , Animais , Brônquios/imunologia , Citocinas/imunologia , Interleucina-13/imunologia , Interleucina-33/imunologia , Camundongos , Linfócitos T Reguladores/imunologia , Células Th2/imunologia , Linfopoietina do Estroma do TimoRESUMO
BACKGROUND: Approximately half the patients with ulcerative colitis who undergo restorative proctocolectomy with ileal pouch-anal anastomosis (IPAA) will subsequently have pouchitis, and among those patients, one fifth will have chronic pouchitis. METHODS: We conducted a phase 4, double-blind, randomized trial to evaluate vedolizumab in adult patients in whom chronic pouchitis had developed after undergoing IPAA for ulcerative colitis. Patients were assigned (in a 1:1 ratio) to receive vedolizumab intravenously at a dose of 300 mg or placebo on day 1 and at weeks 2, 6, 14, 22, and 30. All the patients received concomitant ciprofloxacin from weeks 1 to 4. The primary end point was modified Pouchitis Disease Activity Index (mPDAI)-defined remission (an mPDAI score of ≤4 and a reduction from baseline of ≥2 points in the mPDAI total score; scores range from 0 to 12, with higher scores indicating more severe pouchitis) at week 14. The mPDAI is based on clinical symptoms and endoscopic findings. Other efficacy end points included mPDAI-defined remission at week 34, mPDAI-defined response (a reduction from baseline of ≥2 points in the mPDAI score) at weeks 14 and 34, and PDAI-defined remission (a PDAI score of ≤6 and a reduction from baseline of ≥3 points; scores range from 0 to 18, with higher scores indicating more severe pouchitis) at weeks 14 and 34. The PDAI is based on clinical symptoms, endoscopic findings, and histologic findings. RESULTS: Among the 102 patients who underwent randomization, the incidence of mPDAI-defined remission at week 14 was 31% (16 of 51 patients) with vedolizumab and 10% (5 of 51 patients) with placebo (difference, 21 percentage points; 95% confidence interval [CI], 5 to 38; P = 0.01). Differences in favor of vedolizumab over placebo were also seen with respect to mPDAI-defined remission at week 34 (difference, 17 percentage points; 95% CI, 0 to 35), mPDAI-defined response at week 14 (difference, 30 percentage points; 95% CI, 8 to 48) and at week 34 (difference, 22 percentage points; 95% CI, 2 to 40), and PDAI-defined remission at week 14 (difference, 25 percentage points; 95% CI, 8 to 41) and at week 34 (difference, 19 percentage points; 95% CI, 2 to 37). Serious adverse events occurred in 3 of 51 patients (6%) in the vedolizumab group and in 4 of 51 patients (8%) in the placebo group. CONCLUSIONS: Treatment with vedolizumab was more effective than placebo in inducing remission in patients who had chronic pouchitis after undergoing IPAA for ulcerative colitis. (Funded by Takeda; EARNEST ClinicalTrials.gov number, NCT02790138; EudraCT number, 2015-003472-78.).
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Colite Ulcerativa , Fármacos Gastrointestinais , Pouchite , Proctocolectomia Restauradora , Adulto , Humanos , Anticorpos Monoclonais Humanizados/administração & dosagem , Anticorpos Monoclonais Humanizados/uso terapêutico , Ciprofloxacina/administração & dosagem , Ciprofloxacina/uso terapêutico , Colite Ulcerativa/complicações , Colite Ulcerativa/cirurgia , Pouchite/tratamento farmacológico , Pouchite/etiologia , Doença Crônica , Fármacos Gastrointestinais/administração & dosagem , Fármacos Gastrointestinais/uso terapêutico , Proctocolectomia Restauradora/efeitos adversos , Método Duplo-Cego , Antibacterianos/administração & dosagem , Antibacterianos/uso terapêutico , Administração Intravenosa , Quimioterapia CombinadaRESUMO
OBJECTIVES: To develop a multiparametric machine-learning (ML) framework using high-resolution 3 dimensional (3D) magnetic resonance (MR) fingerprinting (MRF) data for quantitative characterization of focal cortical dysplasia (FCD). MATERIALS: We included 119 subjects, 33 patients with focal epilepsy and histopathologically confirmed FCD, 60 age- and gender-matched healthy controls (HCs), and 26 disease controls (DCs). Subjects underwent whole-brain 3 Tesla MRF acquisition, the reconstruction of which generated T1 and T2 relaxometry maps. A 3D region of interest was manually created for each lesion, and z-score normalization using HC data was performed. We conducted 2D classification with ensemble models using MRF T1 and T2 mean and standard deviation from gray matter and white matter for FCD versus controls. Subtype classification additionally incorporated entropy and uniformity of MRF metrics, as well as morphometric features from the morphometric analysis program (MAP). We translated 2D results to individual probabilities using the percentage of slices above an adaptive threshold. These probabilities and clinical variables were input into a support vector machine for individual-level classification. Fivefold cross-validation was performed and performance metrics were reported using receiver-operating-characteristic-curve analyses. RESULTS: FCD versus HC classification yielded mean sensitivity, specificity, and accuracy of 0.945, 0.980, and 0.962, respectively; FCD versus DC classification achieved 0.918, 0.965, and 0.939. In comparison, visual review of the clinical magnetic resonance imaging (MRI) detected 48% (16/33) of the lesions by official radiology report. In the subgroup where both clinical MRI and MAP were negative, the MRF-ML models correctly distinguished FCD patients from HCs and DCs in 98.3% of cross-validation trials for the magnetic resonance imaging negative group and MAP negative group. Type II versus non-type-II classification exhibited mean sensitivity, specificity, and accuracy of 0.835, 0.823, and 0.83, respectively; type IIa versus IIb classification showed 0.85, 0.9, and 0.87. In comparison, the transmantle sign was present in 58% (7/12) of the IIb cases. INTERPRETATION: The MRF-ML framework presented in this study demonstrated strong efficacy in noninvasively classifying FCD from normal cortex and distinguishing FCD subtypes. ANN NEUROL 2024.
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BACKGROUND & AIMS: Vedolizumab is indicated for the treatment of chronic pouchitis in the European Union. We assessed whether vedolizumab induced mucosal healing (MH) and if MH was associated with clinical improvements. METHODS: EARNEST, a randomized, double-blind, placebo-controlled study, evaluated vedolizumab efficacy and safety in adults with chronic pouchitis. Centrally read endoscopic and histologic evaluation was performed at baseline, Week (W)14, and W34. Ulcer count, adapted Simple Endoscopic Score for Crohn's Disease in the pouch, and Pouchitis Disease Activity Index histologic component were evaluated. Pouchitis Disease Activity Index and Inflammatory Bowel Disease Questionnaire remission at W14 and W34 were compared by MH status at W14. RESULTS: Following treatment, mean (standard deviation) number of ulcers in vedolizumab-treated patients reduced from 15.1 (16.4) to 5.0 (4.9) at W14 and 2.7 (3.2) at W34 versus placebo-treated patients with corresponding values of 11.8 (11.3), 13.4 (18.4), and 9.7 (13.8) (vedolizumab vs placebo difference [95% confidence interval]: W14: -8.4 [-14.3 to -2.6]; W34: -7.0 [-12.0 to -2.0]). More patients receiving vedolizumab versus placebo achieved reduction in ulcerated pouch surface area (W14: 52.4% vs 20.0%; difference, 32.4 percentage points [p.p] [9.7, 51.4]; W34: 52.1% vs 12.9%; difference, 40.2p.p [15.6, 60.3]), absence of ulceration (W14: 23.8% vs 7.5%; difference, 16.3p.p [1.1, 31.6]; W34: 34.4% vs 15.6%; difference, 18.8p.p [-2.0, 39.5]), Simple Endoscopic Score for Crohn's Disease remission (W14: 23.8% vs 7.5%; difference, 16.3p.p [1.1, 31.6]; W34: 34.4% vs 15.6%; difference, 18.8p.p [-2.0, 39.5]), and MH (W14: 16.7% vs 2.5%; difference, 14.2p.p [1.9, 26.4]). Patients with MH at W14 had higher rates of Pouchitis Disease Activity Index and Inflammatory Bowel Disease Questionnaire remission at W14 and W34 than those without. CONCLUSIONS: Vedolizumab induced endoscopic improvements in patients with chronic pouchitis, which was associated with improved outcomes at W34, particularly in patients achieving MH at W14. (ClinicalTrials.gov number, NCT02790138.).
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BACKGROUND: Improved monitoring of Mycobacterium tuberculosis response to treatment is urgently required. We previously developed the molecular bacterial load assay (MBLA), but it is challenging to integrate into the clinical diagnostic laboratory due to a labor-intensive protocol required at biosafety level 3 (BSL-3). A modified assay was needed. METHODS: The rapid enumeration and diagnostic for tuberculosis (READ-TB) assay was developed. Acetic acid was tested and compared to 4â M guanidine thiocyanate to be simultaneously bactericidal and preserve mycobacterial RNA. The extraction was based on silica column technology and incorporated low-cost reagents: 3â M sodium acetate and ethanol for the RNA extraction to replace phenol-chloroform. READ-TB was fully validated and compared directly to the MBLA using sputa collected from individuals with tuberculosis. RESULTS: Acetic acid was bactericidal to M. tuberculosis with no significant loss in 16S rRNA or an unprotected mRNA fragment when sputum was stored in acetic acid at 25°C for 2 weeks or -20°C for 1 year. This novel use of acetic acid allows processing of sputum for READ-TB at biosafety level 2 (BSL-2) on sample receipt. READ-TB is semiautomated and rapid. READ-TB correlated with the MBLA when 85 human sputum samples were directly compared (R2 = 0.74). CONCLUSIONS: READ-TB is an improved version of the MBLA and is available to be adopted by clinical microbiology laboratories as a tool for tuberculosis treatment monitoring. READ-TB will have a particular impact in low- and middle-income countries (LMICs) for laboratories with no BSL-3 laboratory and for clinical trials testing new combinations of anti-tuberculosis drugs.
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Mycobacterium tuberculosis , Tuberculose , Humanos , Mycobacterium tuberculosis/genética , Ácido Acético , Escarro , Laboratórios , RNA Ribossômico 16S/genética , Contenção de Riscos Biológicos , Tuberculose/diagnóstico , Tuberculose/microbiologiaRESUMO
In this Letter, a digital self-aligned focusing schlieren (D-SAFS) system is introduced. This system uses a digital transparent micro liquid crystal display (µLCD), in combination with a linear polarizer, to act on the linear polarization state of light transmitted in both the forward and reverse directions, essentially acting as both the source and cutoff grids. The use of the µLCD display allows for on-the-fly changes to the cutoff pattern type, spatial frequency, and orientation. This eliminates the need to physically access the source/cutoff grid in order to optimize the instrument's sensitivity, which is necessary with a conventional self-aligned focusing schlieren (SAFS) system.
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OBJECTIVE: We aim to improve focal cortical dysplasia (FCD) detection by combining high-resolution, three-dimensional (3D) magnetic resonance fingerprinting (MRF) with voxel-based morphometric magnetic resonance imaging (MRI) analysis. METHODS: We included 37 patients with pharmacoresistant focal epilepsy and FCD (10 IIa, 15 IIb, 10 mild Malformation of Cortical Development [mMCD], and 2 mMCD with oligodendroglial hyperplasia and epilepsy [MOGHE]). Fifty-nine healthy controls (HCs) were also included. 3D lesion labels were manually created. Whole-brain MRF scans were obtained with 1 mm3 isotropic resolution, from which quantitative T1 and T2 maps were reconstructed. Voxel-based MRI postprocessing, implemented with the morphometric analysis program (MAP18), was performed for FCD detection using clinical T1w images, outputting clusters with voxel-wise lesion probabilities. Average MRF T1 and T2 were calculated in each cluster from MAP18 output for gray matter (GM) and white matter (WM) separately. Normalized MRF T1 and T2 were calculated by z-scores using HCs. Clusters that overlapped with the lesion labels were considered true positives (TPs); clusters with no overlap were considered false positives (FPs). Two-sample t-tests were performed to compare MRF measures between TP/FP clusters. A neural network model was trained using MRF values and cluster volume to distinguish TP/FP clusters. Ten-fold cross-validation was used to evaluate model performance at the cluster level. Leave-one-patient-out cross-validation was used to evaluate performance at the patient level. RESULTS: MRF metrics were significantly higher in TP than FP clusters, including GM T1, normalized WM T1, and normalized WM T2. The neural network model with normalized MRF measures and cluster volume as input achieved mean area under the curve (AUC) of .83, sensitivity of 82.1%, and specificity of 71.7%. This model showed superior performance over direct thresholding of MAP18 FCD probability map at both the cluster and patient levels, eliminating ≥75% FP clusters in 30% of patients and ≥50% of FP clusters in 91% of patients. SIGNIFICANCE: This pilot study suggests the efficacy of MRF for reducing FPs in FCD detection, due to its quantitative values reflecting in vivo pathological changes. © 2024 International League Against Epilepsy.
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Imageamento por Ressonância Magnética , Malformações do Desenvolvimento Cortical , Humanos , Imageamento por Ressonância Magnética/métodos , Feminino , Masculino , Adulto , Malformações do Desenvolvimento Cortical/diagnóstico por imagem , Malformações do Desenvolvimento Cortical/patologia , Adolescente , Adulto Jovem , Epilepsias Parciais/diagnóstico por imagem , Epilepsias Parciais/patologia , Pessoa de Meia-Idade , Epilepsia Resistente a Medicamentos/diagnóstico por imagem , Epilepsia Resistente a Medicamentos/patologia , Imageamento Tridimensional/métodos , Criança , Reações Falso-Positivas , Substância Cinzenta/diagnóstico por imagem , Substância Cinzenta/patologia , Processamento de Imagem Assistida por Computador/métodos , Displasia Cortical FocalRESUMO
INTRODUCTION: Cerebral amyloid angiopathy (CAA) is characterized by amyloid ß (Aß) deposition in brain vessels, leading to hemorrhagic phenomena and cognitive impairment. Magnetic resonance imaging (MRI)-based criteria allow a diagnosis of probable CAA in vivo, but such a diagnosis cannot predict the eventual development of CAA. METHODS: We conducted a retrospective cohort study of 464 patients with cognitive disorders whose data were included in a brain health biobank. De-identified parameters including sex, age, cognitive score, APOE status, and cerebrospinal fluid (CSF) levels of Aß 1-40, Aß 1-42, phosphorylated tau, and total tau were assessed in those with and without CAA. Odds ratios (ORs) and 95% confidence intervals (CIs) were determined. RESULTS: CAA was present in 53 of 464 (11.5%) patients. P-tau level was significantly higher in those with CAA (115 vs. 84.3 pg/mL p = 0.038). In univariate analyses, the risk of developing CAA was higher with increased age (OR, 1.036; 95% CI: 1.008, 1.064; p = 0.011) and decreased CSF level of Aß 1-40 (OR, 0.685; 95% CI: 0.534, 0.878; p = 0.003). In multivariate analyses, the risk of CAA remained higher with a decreased CSF level of Aß 1-40 (OR, 0.681; 95% CI: 0.531, 0.874; p = 0.003). CONCLUSION: These findings suggest that Aß 1-40 levels in the CSF might be a useful molecular biomarker of CAA in patients with dementia.
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Aviation passenger screening has been used worldwide to mitigate the translocation risk of SARS-CoV-2. We present a model that evaluates factors in screening strategies used in air travel and assess their relative sensitivity and importance in identifying infectious passengers. We use adapted Monte Carlo simulations to produce hypothetical disease timelines for the Omicron variant of SARS-CoV-2 for travelling passengers. Screening strategy factors assessed include having one or two RT-PCR and/or antigen tests prior to departure and/or post-arrival, and quarantine length and compliance upon arrival. One or more post-arrival tests and high quarantine compliance were the most important factors in reducing pathogen translocation. Screening that combines quarantine and post-arrival testing can shorten the length of quarantine for travelers, and variability and mean testing sensitivity in post-arrival RT-PCR and antigen tests decrease and increase with the greater time between the first and second post-arrival test, respectively. This study provides insight into the role various screening strategy factors have in preventing the translocation of infectious diseases and a flexible framework adaptable to other existing or emerging diseases. Such findings may help in public health policy and decision-making in present and future evidence-based practices for passenger screening and pandemic preparedness.
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Viagem Aérea , COVID-19 , Humanos , COVID-19/diagnóstico , COVID-19/epidemiologia , COVID-19/prevenção & controle , SARS-CoV-2/genética , Método de Monte CarloRESUMO
Quantitative magnetic resonance (MR) has been used to study cyto- and myelo-architecture of the human brain non-invasively. However, analyzing brain cortex using high-resolution quantitative MR acquisition can be challenging to perform using 3T clinical scanners. MR fingerprinting (MRF) is a highly efficient and clinically feasible quantitative MR technique that simultaneously provides T1 and T2 relaxation maps. Using 3D MRF from 40 healthy subjects (mean age = 25.6 ± 4.3 years) scanned on 3T magnetic resonance imaging, we generated whole-brain gyral-based normative MR relaxation atlases and investigated cortical-region-based T1 and T2 variations. Gender and age dependency of T1 and T2 variations were additionally analyzed. The coefficient of variation of T1 and T2 for each cortical-region was 3.5% and 7.3%, respectively, supporting low variability of MRF measurements across subjects. Significant differences in T1 and T2 were identified among 34 brain regions (P < 0.001), lower in the precentral, postcentral, paracentral lobule, transverse temporal, lateral occipital, and cingulate areas, which contain sensorimotor, auditory, visual, and limbic functions. Significant correlations were identified between age and T1 and T2 values. This study established whole-brain MRF T1 and T2 atlases of healthy subjects using a clinical 3T scanner, which can provide a quantitative and region-specific baseline for future brain studies and pathology detection.
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Encéfalo , Imageamento por Ressonância Magnética , Humanos , Adulto Jovem , Adulto , Lactente , Imageamento por Ressonância Magnética/métodos , Espectroscopia de Ressonância Magnética , Imagens de Fantasmas , Voluntários Saudáveis , Processamento de Imagem Assistida por Computador/métodosRESUMO
We have shown previously that phosphorylation of Mdm2 by ATM and c-Abl regulates Mdm2-p53 signaling and alters the effects of DNA damage in mice, including bone marrow failure and tumorigenesis induced by ionizing radiation. Here, we examine the physiological effects of Mdm2 phosphorylation by Akt, another DNA damage effector kinase. Surprisingly, Akt phosphorylation of Mdm2 does not alter the p53-mediated effects of ionizing radiation in cells or mice but regulates the p53 response to oxidative stress. Akt phosphorylation of Mdm2 serine residue 183 increases nuclear Mdm2 stability, decreases p53 levels, and prevents senescence in primary cells exposed to reactive oxidative species (ROS). Using multiple mouse models of ROS-induced cancer, we show that Mdm2 phosphorylation by Akt reduces senescence to promote KrasG12D-driven lung cancers and carcinogen-induced papilloma and hepatocellular carcinomas. Collectively, we document a unique physiologic role for Akt-Mdm2-p53 signaling in regulating cell growth and tumorigenesis in response to oxidative stress.
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Neoplasias Induzidas por Radiação/genética , Proteínas Proto-Oncogênicas c-akt/genética , Proteínas Proto-Oncogênicas c-mdm2/genética , Proteínas Proto-Oncogênicas p21(ras)/genética , Proteína Supressora de Tumor p53/genética , Animais , Apoptose/efeitos dos fármacos , Apoptose/efeitos da radiação , Carcinogênese/efeitos dos fármacos , Carcinogênese/genética , Carcinogênese/efeitos da radiação , Carcinógenos/toxicidade , Carcinoma Hepatocelular/induzido quimicamente , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/virologia , Proliferação de Células/genética , Senescência Celular/efeitos dos fármacos , Senescência Celular/efeitos da radiação , Dano ao DNA/genética , Dano ao DNA/efeitos da radiação , Modelos Animais de Doenças , Humanos , Neoplasias Hepáticas/induzido quimicamente , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/virologia , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Camundongos , Neoplasias Induzidas por Radiação/patologia , Estresse Oxidativo/efeitos dos fármacos , Estresse Oxidativo/efeitos da radiação , Papillomaviridae/patogenicidade , Fosforilação/efeitos dos fármacos , Fosforilação/efeitos da radiação , Radiação Ionizante , Espécies Reativas de Oxigênio/metabolismoRESUMO
Debates about Islamophobia have been blighted by the question of whether the prejudice can be defined as a form of racism or as hostility to religion (or a combination of the two). This paper sheds light on this debate by presenting the findings of a new nationally representative survey, focused on the UK, that contrasts perceptions of Muslims not only with perceptions of other ethnic and religious minorities but also with perceptions of Islam as a religious tradition. We find that prejudice against Muslims is higher than for any other group examined other than Travellers. We also find contrasting demographic drivers of prejudice towards Muslims and towards Islam. Across most prejudice measures we analyse, intolerant views are generally significantly associated with being male, voting Conservative and being older, although not with Anglican identity. We find, however, that class effects vary depending on the question's focus. Anti-immigration sentiment - including support for a 'Muslim ban' - is significantly correlated with being working-class. However, prejudice towards Islam as a body of teachings (tested using a question measuring perceptions of religious literalism) is significantly correlated with being middle-class, as is negative sentiment towards Travellers. Using these findings, the paper makes an argument for supplementing recent scholarship on the associations between racism and Islamophobia with analyses focusing on misperceptions of belief.
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Racismo , Masculino , Humanos , Feminino , Islamismo , Preconceito , Religião , Atitude , Emigração e Imigração , HostilidadeRESUMO
In multicopper oxidases (MCOs), the type 1 (T1) Cu accepts electrons from the substrate and transfers these to the trinuclear Cu cluster (TNC) where O2 is reduced to H2O. The T1 potential in MCOs varies from 340 to 780 mV, a range not explained by the existing literature. This study focused on the â¼350 mV difference in potential of the T1 center in Fet3p and Trametes versicolor laccase (TvL) that have the same 2His1Cys ligand set. A range of spectroscopies performed on the oxidized and reduced T1 sites in these MCOs shows that they have equivalent geometric and electronic structures. However, the two His ligands of the T1 Cu in Fet3p are H-bonded to carboxylate residues, while in TvL they are H-bonded to noncharged groups. Electron spin echo envelope modulation spectroscopy shows that there are significant differences in the second-sphere H-bonding interactions in the two T1 centers. Redox titrations on type 2-depleted derivatives of Fet3p and its D409A and E185A variants reveal that the two carboxylates (D409 and E185) lower the T1 potential by 110 and 255-285 mV, respectively. Density functional theory calculations uncouple the effects of the charge of the carboxylates and their difference in H-bonding interactions with the His ligands on the T1 potential, indicating 90-150 mV for anionic charge and â¼100 mV for a strong H-bond. Finally, this study provides an explanation for the generally low potentials of metallooxidases relative to the wide range of potentials of the organic oxidases in terms of different oxidized states of their TNCs involved in catalytic turnover.
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Ceruloplasmina , Histidina , Ceruloplasmina/química , Ligantes , Cobre/química , Trametes , Eletricidade Estática , Lacase/metabolismoRESUMO
Lytic polysaccharide monooxygenases (LPMOs) catalyze the degradation of recalcitrant carbohydrate polysaccharide substrates. These enzymes are characterized by a mononuclear Cu(I) active site with a three-coordinate T-shaped "His-brace" configuration including the N-terminal histidine and its amine group as ligands. This study explicitly investigates the electronic structure of the d10 Cu(I) active site in a LPMO using Kß X-ray emission spectroscopy (XES). The lack of inversion symmetry in the His-brace site enables the 3d/p mixing required for intensity in the Kß valence-to-core (VtC) XES spectrum of Cu(I)-LPMO. These Kß XES data are correlated to density functional theory (DFT) calculations to define the bonding, and in particular, the frontier molecular orbital (FMO) of the Cu(I) site. These experimentally validated DFT calculations are used to evaluate the reaction coordinate for homolytic cleavage of the H2O2 O-O bond and understand the contribution of this FMO to the low barrier of this reaction and how the geometric and electronic structure of the Cu(I)-LPMO site is activated for rapid reactivity with H2O2.
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Peróxido de Hidrogênio , Oxigenases de Função Mista , Oxigenases de Função Mista/química , Polissacarídeos/metabolismo , Domínio Catalítico , Espectrometria por Raios XRESUMO
BACKGROUND: Limited research has studied the influence of social determinants of health (SDoH) on the receipt, disease risk, and subsequent effectiveness of neutralizing monoclonal antibodies (nMAbs) for outpatient treatment of COVID-19. OBJECTIVE: To examine the influence of SDoH variables on receiving nMAb treatments and the risk of a poor COVID-19 outcome, as well as nMAb treatment effectiveness across SDoH subgroups. DESIGN: Retrospective observational study utilizing electronic health record data from four health systems. SDoH variables analyzed included race, ethnicity, insurance, marital status, Area Deprivation Index, and population density. PARTICIPANTS: COVID-19 patients who met at least one emergency use authorization criterion for nMAb treatment. MAIN MEASURE: We used binary logistic regression to examine the influence of SDoH variables on receiving nMAb treatments and risk of a poor outcome from COVID-19 and marginal structural models to study treatment effectiveness. RESULTS: The study population included 25,241 (15.1%) nMAb-treated and 141,942 (84.9%) non-treated patients. Black or African American patients were less likely to receive treatment than white non-Hispanic patients (adjusted odds ratio (OR) = 0.86; 95% CI = 0.82-0.91). Patients who were on Medicaid, divorced or widowed, living in rural areas, or living in areas with the highest Area Deprivation Index (most vulnerable) had lower odds of receiving nMAb treatment, but a higher risk of a poor outcome. For example, compared to patients on private insurance, Medicaid patients had 0.89 (95% CI = 0.84-0.93) times the odds of receiving nMAb treatment, but 1.18 (95% CI = 1.13-1.24) times the odds of a poor COVID-19 outcome. Age, comorbidities, and COVID-19 vaccination status had a stronger influence on risk of a poor outcome than SDoH variables. nMAb treatment benefited all SDoH subgroups with lower rates of 14-day hospitalization and 30-day mortality. CONCLUSION: Disparities existed in receiving nMAbs within SDoH subgroups despite the benefit of treatment across subgroups.
Assuntos
Vacinas contra COVID-19 , COVID-19 , Estados Unidos/epidemiologia , Humanos , Pacientes Ambulatoriais , Determinantes Sociais da Saúde , COVID-19/epidemiologia , COVID-19/terapia , Anticorpos MonoclonaisRESUMO
OBJECTIVE: We aim to quantify whole-brain tissue-property changes in patients with magnetic resonance imaging (MRI)-negative pharmacoresistant focal epilepsy by three-dimensional (3D) magnetic resonance fingerprinting (MRF). METHODS: We included 30 patients with pharmacoresistant focal epilepsy and negative MRI by official radiology report, as well as 40 age- and gender-matched healthy controls (HCs). MRF scans were obtained with 1 mm3 isotropic resolution. Quantitative T1 and T2 relaxometry maps were reconstructed from MRF and registered to the Montreal Neurological Institute (MNI) space. A two-sample t test was performed in Functional Magnetic Resonance Imaging of the Brain (FMRIB) Software Library (FSL) to evaluate significant abnormalities in patients comparing to HCs, with correction by the threshold-free cluster enhancement (TFCE) method. Subgroups analyses were performed for extra-temporal epilepsy/temporal epilepsy (ETLE/TLE), and for those with/without subtle abnormalities detected by morphometric analysis program (MAP), to investigate each subgroup's pattern of MRF changes. Correlation analyses were performed between the mean MRF values in each significant cluster and seizure-related clinical variables. RESULTS: Compared to HCs, patients exhibited significant group-level T1 increase ipsilateral to the epileptic origin, in the mesial temporal gray matter (GM) and white matter (WM), temporal pole GM, orbitofrontal GM, hippocampus, and amygdala, with scattered clusters in the neocortical temporal and insular GM. No significant T2 changes were detected. The ETLE subgroup showed a T1-increase pattern similar to the overall cohort, with additional involvement of the ipsilateral anterior cingulate GM. The subgroup of MAP+ patients also showed a T1-increase pattern similar to the overall cohort, with additional cluster in the ipsilateral lateral orbitofrontal GM. Higher T1 was associated with younger seizure-onset age, longer epilepsy duration, and higher seizure frequency. SIGNIFICANCE: MRF revealed group-level T1 increase in limbic/paralimbic structures ipsilateral to the epileptic origin, in patients with pharmacoresistant focal epilepsy and no apparent lesions on MRI, suggesting that these regions may be commonly affected by seizures in the epileptic brain. The significant association between T1 increase and higher seizure burden may reflect progressive tissue damage.