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1.
J Neurol ; 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-39088063

RESUMO

INTRODUCTION: FTLD-FET is a newly described subtype of frontotemporal lobar degeneration (FTLD characterized by pathologic inclusions of FET proteins: fused in sarcoma (FUS), Ewing sarcoma, and TATA-binding protein-associated factor 2N (TAF15)). Severe caudate volume loss on MRI has been linked to FTLD-FUS, yet glucose hypometabolism in FTLD-FET has not been studied. We assessed [18F] fluorodeoxyglucose PET (FDG-PET) hypometabolism in FTLD-FET subtypes and compared metabolism to FTLD-tau and FTLD-TDP. METHODS: We retrospectively reviewed medical records of 26 autopsied FTLD patients (six FTLD-FET, ten FTLD-Tau, and ten FTLD-TDP) who had completed antemortem FDG-PET. We evaluated five regions, caudate nucleus, medial frontal cortex, lateral frontal cortex, and medial temporal using a 0-3 visual rating scale and validated our findings quantitatively using CORTEX-ID suite Z scores. RESULTS: Of the six FTLD-FET cases (three females) with median age at onset = 36, three were atypical FTLD-U (aFTLD-U) and three were neuronal intermediate filament inclusion disease (NIFID). bvFTD was the most common presentation. Four of the six FTLD cases (3 aFTLD-U + 1 NIFID) showed prominent caudate hypometabolism relatively early in the disease course. FTLD-tau and FTLD-TDP did not show early prominent caudate hypometabolism. Hypometabolism in medial and lateral temporal cortex was associated with FTLD-TDP, while FTLD-tau had normal-minimal regional metabolism. DISCUSSION: Prominent caudate hypometabolism, especially early in the disease course, appears to be a hallmark feature of the aFTLD-U subtype of FTLD-FET. Assessing caudate and temporal hypometabolism on FDG-PET will help to differentiate FTLD-FET from FTLD-tau and FTLD-TDP.

2.
Brain Commun ; 6(4): fcae233, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39056025

RESUMO

Progressive supranuclear palsy (PSP) is a neurodegenerative tauopathy that presents with highly heterogenous clinical syndromes. We perform cross-sectional data-driven discovery of independent patterns of brain atrophy and hypometabolism across the entire PSP spectrum. We then use these patterns to predict specific clinical features and to assess their relationship to phenotypic heterogeneity. We included 111 patients with PSP (60 with Richardson syndrome and 51 with cortical and subcortical variant subtypes). Ninety-one were used as the training set and 20 as a test set. The presence and severity of granular clinical variables such as postural instability, parkinsonism, apraxia and supranuclear gaze palsy were noted. Domains of akinesia, ocular motor impairment, postural instability and cognitive dysfunction as defined by the Movement Disorders Society criteria for PSP were also recorded. Non-negative matrix factorization was used on cross-sectional MRI and fluorodeoxyglucose-positron emission tomography (FDG-PET) scans. Independent models for each as well as a combined model for MRI and FDG-PET were developed and used to predict the granular clinical variables. Both MRI and FDG-PET were better at predicting presence of a symptom than severity, suggesting identification of disease state may be more robust than disease stage. FDG-PET predicted predominantly cortical abnormalities better than MRI such as ideomotor apraxia, apraxia of speech and frontal dysexecutive syndrome. MRI demonstrated prediction of cortical and more so sub-cortical abnormalities, such as parkinsonism. Distinct neuroanatomical foci were predictive in MRI- and FDG-PET-based models. For example, vertical gaze palsy was predicted by midbrain atrophy on MRI, but frontal eye field hypometabolism on FDG-PET. Findings also differed by scale or instrument used. For example, prediction of ocular motor abnormalities using the PSP Saccadic Impairment Scale was stronger than with the Movement Disorders Society Diagnostic criteria for PSP oculomotor impairment designation. Combination of MRI and FDG-PET demonstrated enhanced detection of parkinsonism and frontal syndrome presence and apraxia, cognitive impairment and bradykinesia severity. Both MRI and FDG-PET patterns were able to predict some measures in the test set; however, prediction of global cognition measured by Montreal Cognitive Assessment was the strongest. MRI predictions generalized more robustly to the test set. PSP leads to neurodegeneration in motor, cognitive and ocular motor networks at cortical and subcortical foci, leading to diverse yet overlapping clinical syndromes. To advance understanding of phenotypic heterogeneity in PSP, it is essential to consider data-driven approaches to clinical neuroimaging analyses.

3.
Mem Cognit ; 2024 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-39060852

RESUMO

In the current study, we investigated how long the effects of one single collaboration session continue to influence individual memory. Participants learned categorized word lists and prose passages individually, and then they were instructed to recall learned materials either collaboratively or individually. Following initial recall, participants completed an individual recall test after a delay of 5 min, 48 h, or 1 week. On the initial recall test, we found that collaboration reduced recall of correct items on both word lists and prose passages (collaborative inhibition), and that collaboration reduced false recall on both word lists and prose passages (error correction). However, on the subsequent individual memory test after a delay, the pattern of post collaborative effects differed across veridical and false recall. For both word lists and prose passages, post collaborative benefits on correct recall lasted 1 week. However, there were no lasting effects of error correction on subsequent false recall. These results suggest that the time course of post collaborative benefits can be long lasting, but they are selective to veridical recall. The results are explained by theories of reexposure and error correction.

4.
Clin Nurs Res ; : 10547738241267159, 2024 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-39066626

RESUMO

The objective of this article is to illustrate the importance of the role philosophy and its tools play in the designing and undertaking of nursing research and its importance to be understood by the practicing researcher to ensure the selected methodology and the tools used provide the framework for obtaining reliable and valid answers to their research questions. The article discusses the three major paradigms (Positivism, Interpretivism, and Pragmatism) which have characterized much of health-related research together with a set of essential and practical tools with no metaphysical assumptions that will hopefully provide an explicit framework and a nomenclature which can be applied as we proceed through the research process.

5.
Prev Chronic Dis ; 21: E51, 2024 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-38991533

RESUMO

Introduction: PCORnet, the National Patient-Centered Clinical Research Network, is a large research network of health systems that map clinical data to a standardized data model. In 2018, we expanded existing infrastructure to facilitate use for public health surveillance. We describe benefits and challenges of using PCORnet for surveillance and describe case studies. Methods: In 2018, infrastructure enhancements included addition of a table to store patients' residential zip codes and expansion of a modular program to generate population health statistics across conditions. Chronic disease surveillance case studies conducted in 2019 assessed atrial fibrillation (AF) and cirrhosis. In April 2020, PCORnet established an infrastructure to support COVID-19 surveillance with institutions frequently updating their electronic health record data. Results: By August 2023, 53 PCORnet sites (84%) had a 5-digit zip code available on at least 95% of their patient populations. Among 148,223 newly diagnosed AF patients eligible for oral anticoagulant (OAC) therapy, 43.3% were on any OAC (17.8% warfarin, 28.5% any novel oral anticoagulant) within a year of the AF diagnosis. Among 60,268 patients with cirrhosis (2015-2019), common documented etiologies included unknown (48%), hepatitis C infection (23%), and alcohol use (22%). During October 2022 through December 2023, across 34 institutions, the proportion of COVID-19 patients who were cared for in the inpatient setting was 9.1% among 887,051 adults aged 20 years or older and 6.0% among 139,148 children younger than 20 years. Conclusions: PCORnet provides important data that may augment traditional public health surveillance programs across diverse conditions. PCORnet affords longitudinal population health assessments among large catchments of the population with clinical, treatment, and geographic information, with capabilities to deliver rapid information needed during public health emergencies.


Assuntos
COVID-19 , Registros Eletrônicos de Saúde , Vigilância em Saúde Pública , Humanos , COVID-19/epidemiologia , Vigilância em Saúde Pública/métodos , SARS-CoV-2 , Estados Unidos/epidemiologia , Masculino , Fibrilação Atrial/epidemiologia , Fibrilação Atrial/tratamento farmacológico , Feminino
6.
Cureus ; 16(6): e62866, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-39040772

RESUMO

Objective The objective of this study was to assess the feasibility of using an intracameral phenylephrine/ketorolac infusion during cataract surgery as a single agent to prevent postoperative pain, inflammation, and other complications. Methods A prospective, single-group feasibility study was conducted in which phenylephrine/ketorolac infusion was administered during cataract surgery and no perioperative topical drops were initially prescribed. Patients underwent optical coherence tomography, corrected distance visual acuity testing, and slit lamp biomicroscopy examination at perioperative visits, during which they also reported symptoms of pain, irritation, and/or photophobia. A goal adverse event (AE) rate was set at ≤5.0%. Results A total of 94 eyes (60 patients) were included in this study. The AE rate was 13.8% (13/94 eyes) with pain/irritation in eight eyes, cystoid macular edema (CME) in three eyes, and corneal edema in three eyes. Conclusions Based on an AE rate goal of ≤5.0%, using intraoperative, intracameral phenylephrine/ketorolac alone was not deemed a feasible alternative to current postoperative eye drop regimens in our clinical setting. However, a 13.8% AE rate is comparable to the rates of postoperative CME, corneal edema, pain, and irritation in the published literature. Thus, more research is needed to truly define this approach as inferior or non-inferior to the current standard of care.

7.
Biochemistry ; 2024 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-39058279

RESUMO

Hexosaminidases are key enzymes in glycoconjugate metabolism and occur in all kingdoms of life. Here, we have investigated the phylogeny of the GH20 glycosyl hydrolase family in nematodes and identified a ß-hexosaminidase subclade present only in the Dorylaimia. We have expressed one of these, HEX-2 from Trichuris suis, a porcine parasite, and shown that it prefers an aryl ß-N-acetylgalactosaminide in vitro. HEX-2 has an almost neutral pH optimum and is best inhibited by GalNAc-isofagomine. Toward N-glycan substrates, it displays a preference for the removal of GalNAc residues from LacdiNAc motifs as well as the GlcNAc attached to the α1,3-linked core mannose. Therefore, it has a broader specificity than insect fused lobe (FDL) hexosaminidases but one narrower than distant homologues from plants. Its X-ray crystal structure, the first of any subfamily 1 GH20 hexosaminidase to be determined, is closest to Streptococcus pneumoniae GH20C and the active site is predicted to be compatible with accommodating both GalNAc and GlcNAc. The new structure extends our knowledge about this large enzyme family, particularly as T. suis HEX-2 also possesses the key glutamate residue found in human hexosaminidases of either GH20 subfamily, including HEXD whose biological function remains elusive.

8.
Alzheimers Dement ; 2024 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-38988055

RESUMO

INTRODUCTION: Spatial extent-based measures of how far amyloid beta (Aß) has spread throughout the neocortex may be more sensitive than traditional Aß-positron emission tomography (PET) measures of Aß level for detecting early Aß deposits in preclinical Alzheimer's disease (AD) and improve understanding of Aß's association with tau proliferation and cognitive decline. METHODS: Pittsburgh Compound-B (PIB)-PET scans from 261 cognitively unimpaired older adults from the Harvard Aging Brain Study were used to measure Aß level (LVL; neocortical PIB DVR) and spatial extent (EXT), calculated as the proportion of the neocortex that is PIB+. RESULTS: EXT enabled earlier detection of Aß deposits longitudinally confirmed to reach a traditional LVL-based threshold for Aß+ within 5 years. EXT improved prediction of cognitive decline (Preclinical Alzheimer Cognitive Composite) and tau proliferation (flortaucipir-PET) over LVL. DISCUSSION: These findings indicate EXT may be more sensitive to Aß's role in preclinical AD than level and improve targeting of individuals for AD prevention trials. HIGHLIGHTS: Aß spatial extent (EXT) was measured as the percentage of the neocortex with elevated Pittsburgh Compound-B. Aß EXT improved detection of Aß below traditional PET thresholds. Early regional Aß deposits were spatially heterogeneous. Cognition and tau were more closely tied to Aß EXT than Aß level. Neocortical tau onset aligned with reaching widespread neocortical Aß.

9.
Angew Chem Int Ed Engl ; : e202411171, 2024 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-39022920

RESUMO

The marine Bacteroidota Zobellia galactanivorans has a polysaccharide utilization locus dedicated to the catabolism of the red algal cell wall galactan carrageenan and its unique and industrially important α-3,6-anhydro-D-galactose (ADG) monosaccharide. Here we present the first analysis of the specific molecular interactions the exo-(α-1,3)-3,6-anhydro-D-galactosidase ZgGH129 uses to cope with the strict steric restrictions imposed by its bicyclic ADG substrate - which is ring flipped relative to D-galactose. Crystallographic snapshots of key catalytic states obtained with the natural substrate and novel chemical tools designed to mimic species along the reaction coordinate, together with quantum mechanics/molecular mechanics (QM/MM) metadynamics methods and kinetic studies, demonstrate a retaining mechanism where the second step is rate limiting. The conformational landscape of the constrained 3,6-anhydro-D-galactopyranose ring proceeds through enzyme glycosylation B1,4 → [E4]‡ → E4/1C4 and deglycosylation E4/1C4 → [E4]‡ → B1,4 itineraries limited to the Southern Hemisphere of the Cremer-Pople sphere. These results demonstrate the conformational changes throughout catalysis in a non-standard, sterically restrained, bicyclic monosaccharide and provide a molecular framework for mechanism-based inhibitor design for anhydro-type carbohydrate-processing enzymes and for future applications involving carrageenan degradation. In addition, it provides a rare example of distinct niche-based conformational itineraries within the same carbohydrate-active enzyme family.

10.
Ann Neurol ; 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-39007398

RESUMO

OBJECTIVE: Elevated entorhinal cortex (EC) tau in low beta-amyloid individuals can predict accumulation of pathology and cognitive decline. We compared the accuracy of magnetic resonance imaging (MRI)-derived locus coeruleus integrity, neocortical beta-amyloid burden by positron emission tomography (PET), and hippocampal volume in identifying elevated entorhinal tau signal in asymptomatic individuals who are considered beta-amyloid PET-negative. METHODS: We included 188 asymptomatic individuals (70.78 ± 11.51 years, 58% female) who underwent 3T-MRI of the locus coeruleus, Pittsburgh compound-B (PiB), and Flortaucipir (FTP) PET. Associations between elevated EC tau and neocortical PiB, hippocampal volume, or locus coeruleus integrity were evaluated and compared using logistic regression and receiver operating characteristic analyses in the PiB- sample with a clinical dementia rating (CDR) of 0. Associations with clinical progression (CDR-sum-of-boxes) over a time span of 6 years were evaluated with Cox proportional hazard models. RESULTS: We identified 26 (21%) individuals with high EC FTP in the CDR = 0/PiB- sample. Locus coeruleus integrity was a significantly more sensitive and specific predictor of elevated EC FTP (area under the curve [AUC] = 85%) compared with PiB (AUC = 77%) or hippocampal volume (AUC = 76%). Based on the Youden-index, locus coeruleus integrity obtained a sensitivity of 77% and 85% specificity. Using the resulting locus coeruleus Youden cut-off, lower locus coeruleus integrity was associated with a two-fold increase in clinical progression, including mild cognitive impairment. INTERPRETATION: Locus coeruleus integrity has promise as a low-cost, non-invasive screening instrument to detect early cortical tau deposition and associated clinical progression in asymptomatic, low beta-amyloid individuals. ANN NEUROL 2024.

11.
Sci Adv ; 10(28): eadn0929, 2024 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-38996015

RESUMO

Polar metals are challenging to identify spectroscopically because the fingerprints of electric polarization are often obscured by the presence of screening charges. Here, we unravel unambiguous signatures of a distortive polar order buried in the Fermi sea by probing the nonlinear optical response of materials driven by tailored terahertz fields. We apply this strategy to investigate the topological crystalline insulator Pb1-xSnxTe, tracking its soft phonon mode in the time domain and observing the occurrence of inversion symmetry breaking as a function of temperature. By combining measurements across the material's phase diagram with ab initio calculations, we demonstrate the generality of our approach. These results highlight the potential of terahertz driving fields to reveal polar orders coexisting with itinerant electrons, thus opening additional avenues for material discovery.

12.
Artigo em Inglês | MEDLINE | ID: mdl-39009110

RESUMO

OBJECTIVE: To assess the characteristics and clinical outcomes of patients with lower extremity peripheral artery disease (PAD) in XATOA receiving dual pathway inhibition (DPI) with rivaroxaban 2.5 mg twice daily plus aspirin according to lower extremity revascularisation (LER) history. METHODS: XATOA is an international, multicentre, prospective, single arm registry study. This subanalysis investigated patients with lower extremity PAD according to LER history. Patients with coronary artery disease, PAD, or both, receiving DPI were followed for 12 or more months. Baseline characteristics and clinical outcomes were assessed according to LER history. A time dependency analysis assessed outcomes by time between the most recent LER procedure and the start of DPI. A multivariate analysis assessed the influence of patient characteristics on clinical outcomes. RESULTS: In XATOA (n = 5 532), 2 820 (51.0%) patients had lower extremity PAD, of whom 1 736 (61.6%) had prior LER and 1 084 (38.4%) had no prior LER. Baseline characteristics were generally similar between patients with or without prior LER. A higher proportion of patients with prior LER experienced any treatment emergent clinical events compared with those without prior LER (15.0% vs. 9.4%, respectively), with greater differences observed between incidence rates of limb events, including major adverse limb events (9.06 vs. 4.09 events per 100 patient years, respectively). Similar rates of myocardial infarction, stroke, and major bleeding were observed in both subgroups. Clinical event rates were generally higher in patients who had previous LER for six months or less compared with patients who had previous LET for more than six months before starting DPI, regardless of LER type. Multivariate analyses showed that prior LER was predictive of limb events. CONCLUSION: This subanalysis of XATOA found that prior LER was associated with increased rates of limb events, consistent with results of COMPASS and VOYAGER PAD. Rates of bleeding were also low regardless of LER history and consistent with the findings from these trials.

13.
Alzheimers Dement ; 2024 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-39039896

RESUMO

INTRODUCTION: Understanding early neuropathological changes and their associations with cognition may aid dementia prevention. This study investigated associations of cerebral amyloid and tau positron emission tomography (PET) retention with cognition in a predominately middle-aged community-based cohort and examined factors that may modify these relationships. METHODS: 11C-Pittsburgh compound B amyloid and 18F-flortaucipir tau PET imaging were performed. Associations of amyloid and tau PET with cognition were evaluated using linear regression. Interactions with age, apolipoprotein E (APOE) ε4 status, and education were examined. RESULTS: Amyloid and tau PET were not associated with cognition in the overall sample (N = 423; mean: 57 ± 10 years; 50% female). However, younger age (< 55 years) and APOE ε4 were significant effect modifiers, worsening cognition in the presence of higher amyloid and tau. DISCUSSION: Higher levels of Aß and tau may have a pernicious effect on cognition among APOE ε4 carriers and younger adults, suggesting a potential role for targeted early interventions. HIGHLIGHTS: Risk and resilience factors influenced cognitive vulnerability due to Aß and tau. Higher fusiform tau associated with poorer visuospatial skills in younger adults. APOE ε4 interacted with Aß and tau to worsen cognition across multiple domains.

14.
Alzheimers Dement ; 2024 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-39041435

RESUMO

INTRODUCTION: Tau-positron emission tomography (PET) outcome data of patients with Alzheimer's disease (AD) cannot currently be meaningfully compared or combined when different tracers are used due to differences in tracer properties, instrumentation, and methods of analysis. METHODS: Using head-to-head data from five cohorts with tau PET radiotracers designed to target tau deposition in AD, we tested a joint propagation model (JPM) to harmonize quantification (units termed "CenTauR" [CTR]). JPM is a statistical model that simultaneously models the relationships between head-to-head and anchor point data. JPM was compared to a linear regression approach analogous to the one used in the amyloid PET Centiloid scale. RESULTS: A strong linear relationship was observed between CTR values across brain regions. Using the JPM approach, CTR estimates were similar to, but more accurate than, those derived using the linear regression approach. DISCUSSION: Preliminary findings using the JPM support the development and adoption of a universal scale for tau-PET quantification. HIGHLIGHTS: Tested a novel joint propagation model (JPM) to harmonize quantification of tau PET. Units of common scale are termed "CenTauRs". Tested a Centiloid-like linear regression approach. Using five cohorts with head-to-head tau PET, JPM outperformed linearregressionbased approach. Strong linear relationship was observed between CenTauRs values across brain regions.

15.
bioRxiv ; 2024 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-39026805

RESUMO

Background and purpose: The normal tissue sparing afforded by FLASH radiotherapy (RT) is being intensely investigated for potential clinical translation. Here, we studied the effects of FLASH proton RT (F-PRT) in the reirradiation setting, with or without hypofractionation. Chronic toxicities in three murine models of normal tissue toxicity including the intestine, skin, and bone were investigated. Materials and methods: In studies of the intestine, single-dose irradiation was performed with 12 Gy of Standard proton RT (S-PRT), followed by a second dose of 12 Gy of F-PRT or S-PRT. Additionally, a hypofractionation scheme was applied in the reirradiation setting (3 x 6.4 Gy of F-PRT or S-PRT, given every 48 hrs). In studies of skin/bone of the murine leg, 15 Gy of S-PRT was followed by hypofractionated reirradiation with F-PRT or S-PRT (3 x 11 Gy). Results: Compared to reirradiation with S-PRT, F-PRT reduced intestinal fibrosis and collagen deposition in the reirradiation setting and significantly increased survival rate, demonstrating its protective effects on intestinal tissues. In previously irradiated leg tissues, reirradiation with hypofractionated F-PRT created transient dermatitis that fully resolved in contrast to reirradiation with hypofractionated S-PRT. Lymphedema was also alleviated after a second course of radiation with F-PRT, along with significant reductions in the accumulation of fibrous connective tissue in the skin compared to mice reirradiated with S-PRT. The delivery of a second course of fractionated S-PRT induced tibial fractures in 83.3% of the mice, whereas only 20% of mice reirradiated with F-PRT presented with fractures. Conclusion: These studies provide the first evidence of the sparing effects of F-PRT, in the setting of hypofractionated reirradiation. The results support FLASH as highly relevant to the reirradiation regimen where it exhibits significant potential to minimize chronic complications for patients undergoing RT.

16.
Sci Rep ; 14(1): 15195, 2024 07 02.
Artigo em Inglês | MEDLINE | ID: mdl-38956443

RESUMO

The intestinal epithelium dynamically controls cell cycle, yet no experimental platform exists for directly analyzing cell cycle phases in non-immortalized human intestinal epithelial cells (IECs). Here, we present two reporters and a complete platform for analyzing cell cycle phases in live primary human IECs. We interrogate the transcriptional identity of IECs grown on soft collagen, develop two fluorescent cell cycle reporter IEC lines, design and 3D print a collagen press to make chamber slides for optimal imaging while supporting primary human IEC growth, live image cell cycle dynamics, then assemble a computational pipeline building upon free-to-use programs for semi-automated analysis of cell cycle phases. The PIP-FUCCI construct allows for assigning cell cycle phase from a single image of living cells, and our PIP-H2A construct allows for semi-automated direct quantification of cell cycle phase lengths using our publicly available computational pipeline. Treating PIP-FUCCI IECs with oligomycin demonstrates that inhibiting mitochondrial respiration lengthens G1 phase, and PIP-H2A cells allow us to measure that oligomycin differentially lengthens S and G2/M phases across heterogeneous IECs. These platforms provide opportunities for future studies on pharmaceutical effects on the intestinal epithelium, cell cycle regulation, and more.


Assuntos
Ciclo Celular , Células Epiteliais , Mucosa Intestinal , Humanos , Células Epiteliais/citologia , Células Epiteliais/metabolismo , Mucosa Intestinal/citologia , Mucosa Intestinal/metabolismo , Oligomicinas/farmacologia , Células Cultivadas
17.
bioRxiv ; 2024 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-38948765

RESUMO

Modification of RNA with N6-methyladenosine (m6A) has gained attention in recent years as a general mechanism of gene regulation. In the liver, m6A, along with its associated machinery, has been studied as a potential biomarker of disease and cancer, with impacts on metabolism, cell cycle regulation, and pro-cancer state signaling. However these observational data have yet to be causally examined in vivo. For example, neither perturbation of the key m6A writers Mettl3 and Mettl14, nor the m6A readers Ythdf1 and Ythdf2 have been thoroughly mechanistically characterized in vivo as they have been in vitro. To understand the functions of these machineries, we developed mouse models and found that deleting Mettl14 led to progressive liver injury characterized by nuclear heterotypia, with changes in mRNA splicing, processing and export leading to increases in mRNA surveillance and recycling.

18.
Open Heart ; 11(2)2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38955399

RESUMO

BACKGROUND: The extent to which differences in results from Apixaban for Reduction in Stroke and Other Thromboembolic Events in Atrial Fibrillation (ARISTOTLE) and Rivaroxaban Once Daily Oral Direct Factor Xa Inhibition Compared with Vitamin K Antagonism for Prevention of Stroke and Embolism Trial (ROCKET) atrial fibrillation (AF)-the landmark trials for the approval of apixaban and rivaroxaban, respectively, for non-valvular AF-were influenced by differences in their protocols is debated. The potential influence of selection criteria on trial results was assessed by emulating these trials in data from the Global Anticoagulant Registry in the Field (GARFIELD)-AF registry. METHODS: Vitamin K antagonist (VKA) and non-vitamin K oral antagonist (NOAC) users from GARFIELD-AF were selected according to eligibility for the original ARISTOTLE or ROCKET AF trials. A propensity score overlap weighted Cox model was used to emulate trial randomisation between treatment groups. Adjusted HRs for stroke or systemic embolism (SE) within 2 years of enrolment were calculated for each NOAC versus VKA. RESULTS: Among patients on apixaban, rivaroxaban and VKA, 2570, 3560 and 8005 were eligible for ARISTOTLE, respectively, and 1612, 2005 and 4368, respectively, for ROCKET AF. When selecting for ARISTOTLE criteria, apixaban users had significantly lower stroke/SE risk versus VKA (HR 0.57; 95% CI 0.34 to 0.94) while no reduction was observed with rivaroxaban (HR 0.98; 95% CI 0.68 to 1.40). When selecting for ROCKET AF criteria, safety and efficacy versus VKA were similar across the NOACs. CONCLUSION: Apixaban and rivaroxaban showed similar results versus VKA in high-risk patients selected according to ROCKET AF criteria, whereas differences emerged when selecting for the more inclusive ARISTOTLE criteria. Our results highlight the importance of trial selection criteria in interpreting trial results and underline the problems faced in comparing treatments across rather than within clinical trials.


Assuntos
Fibrilação Atrial , Inibidores do Fator Xa , Seleção de Pacientes , Pirazóis , Piridonas , Rivaroxabana , Acidente Vascular Cerebral , Humanos , Fibrilação Atrial/tratamento farmacológico , Fibrilação Atrial/complicações , Inibidores do Fator Xa/uso terapêutico , Inibidores do Fator Xa/administração & dosagem , Acidente Vascular Cerebral/prevenção & controle , Acidente Vascular Cerebral/etiologia , Pirazóis/uso terapêutico , Piridonas/uso terapêutico , Piridonas/efeitos adversos , Piridonas/administração & dosagem , Rivaroxabana/administração & dosagem , Rivaroxabana/uso terapêutico , Masculino , Feminino , Idoso , Resultado do Tratamento , Sistema de Registros , Administração Oral , Fatores de Risco , Ensaios Clínicos Controlados Aleatórios como Assunto/métodos , Medição de Risco/métodos , Anticoagulantes/uso terapêutico , Vitamina K/antagonistas & inibidores
19.
Alzheimers Res Ther ; 16(1): 148, 2024 07 03.
Artigo em Inglês | MEDLINE | ID: mdl-38961512

RESUMO

BACKGROUND: Leveraging Alzheimer's disease (AD) imaging biomarkers and longitudinal cognitive data may allow us to establish evidence of cognitive resilience (CR) to AD pathology in-vivo. Here, we applied latent class mixture modeling, adjusting for sex, baseline age, and neuroimaging biomarkers of amyloid, tau and neurodegeneration, to a sample of cognitively unimpaired older adults to identify longitudinal trajectories of CR. METHODS: We identified 200 Harvard Aging Brain Study (HABS) participants (mean age = 71.89 years, SD = 9.41 years, 59% women) who were cognitively unimpaired at baseline with 2 or more timepoints of cognitive assessment following a single amyloid-PET, tau-PET and structural MRI. We examined latent class mixture models with longitudinal cognition as the dependent variable and time from baseline, baseline age, sex, neocortical Aß, entorhinal tau, and adjusted hippocampal volume as independent variables. We then examined group differences in CR-related factors across the identified subgroups from a favored model. Finally, we applied our favored model to a dataset from the Alzheimer's Disease Neuroimaging Initiative (ADNI; n = 160, mean age = 73.9 years, SD = 7.6 years, 60% women). RESULTS: The favored model identified 3 latent subgroups, which we labelled as Normal (71% of HABS sample), Resilient (22.5%) and Declining (6.5%) subgroups. The Resilient subgroup exhibited higher baseline cognitive performance and a stable cognitive slope. They were differentiated from other groups by higher levels of verbal intelligence and past cognitive activity. In ADNI, this model identified a larger Normal subgroup (88.1%), a smaller Resilient subgroup (6.3%) and a Declining group (5.6%) with a lower cognitive baseline. CONCLUSION: These findings demonstrate the value of data-driven approaches to identify longitudinal CR groups in preclinical AD. With such an approach, we identified a CR subgroup who reflected expected characteristics based on previous literature, higher levels of verbal intelligence and past cognitive activity.


Assuntos
Imageamento por Ressonância Magnética , Tomografia por Emissão de Pósitrons , Proteínas tau , Humanos , Feminino , Masculino , Idoso , Proteínas tau/metabolismo , Estudos Longitudinais , Estudos Transversais , Idoso de 80 Anos ou mais , Doença de Alzheimer/diagnóstico por imagem , Doença de Alzheimer/patologia , Doença de Alzheimer/psicologia , Doença de Alzheimer/metabolismo , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Encéfalo/metabolismo , Peptídeos beta-Amiloides/metabolismo , Disfunção Cognitiva/diagnóstico por imagem , Disfunção Cognitiva/metabolismo , Cognição/fisiologia , Pessoa de Meia-Idade , Reserva Cognitiva/fisiologia , Biomarcadores , Neuroimagem/métodos
20.
Inj Prev ; 2024 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-39060115

RESUMO

Recognising and removing players with suspected sport-related concussions is crucial for community sports. OBJECTIVES: Quantify rates and factors associated with non-reporting of concussion symptoms in community rugby league. METHODS: Overall, 484 community rugby league players aged ≥18 years and 965 parents of rugby league players aged <18 years completed an online survey, regarding concussion history, knowledge, prevalence and reasons for non-reporting of concussion, long-term implications and perceptions of concussion. RESULTS: Thirty-five percent of players aged ≥18 years and 22% of parents of players aged <18 years reported at least one concussion in the last two seasons. Forty-three percent of players aged ≥18 years and 5% of parents of players aged<18 years surveyed stated they did not report concussion-related symptoms sustained during 2020 and 2021 seasons. The two most common reasons for non-reporting of concussion symptoms were 'didn't want to be ruled out of a match' and 'didn't want to let down the team'. Players aged ≥18 years who received external coaching pressures around concussion were more likely to not report concussion symptoms. Over 40% of parents and players were concerned about the potential long-term implications. Ten percent of players aged ≥18 years and 7% of parents of players aged <18 years would encourage their family members/children to not play rugby league. CONCLUSIONS: Non-reporting rates of suspected concussion symptoms in adult community players were twice as high as in professional rugby league, with similar reasons (wanting to play and not letting the team down). Engaging coaches to prioritise brain health and providing broader and appropriate education on concussion should be focused on, given the concerns reported by community players and parents.

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