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1.
Proc Natl Acad Sci U S A ; 118(27)2021 07 06.
Artículo en Inglés | MEDLINE | ID: mdl-34215692

RESUMEN

Plant diseases are among the major causes of crop yield losses around the world. To confer disease resistance, conventional breeding relies on the deployment of single resistance (R) genes. However, this strategy has been easily overcome by constantly evolving pathogens. Disabling susceptibility (S) genes is a promising alternative to R genes in breeding programs, as it usually offers durable and broad-spectrum disease resistance. In Arabidopsis, the S gene DMR6 (AtDMR6) encodes an enzyme identified as a susceptibility factor to bacterial and oomycete pathogens. Here, we present a model-to-crop translational work in which we characterize two AtDMR6 orthologs in tomato, SlDMR6-1 and SlDMR6-2. We show that SlDMR6-1, but not SlDMR6-2, is up-regulated by pathogen infection. In agreement, Sldmr6-1 mutants display enhanced resistance against different classes of pathogens, such as bacteria, oomycete, and fungi. Notably, disease resistance correlates with increased salicylic acid (SA) levels and transcriptional activation of immune responses. Furthermore, we demonstrate that SlDMR6-1 and SlDMR6-2 display SA-5 hydroxylase activity, thus contributing to the elucidation of the enzymatic function of DMR6. We then propose that SlDMR6 duplication in tomato resulted in subsequent subfunctionalization, in which SlDMR6-2 specialized in balancing SA levels in flowers/fruits, while SlDMR6-1 conserved the ability to fine-tune SA levels during pathogen infection of the plant vegetative tissues. Overall, this work not only corroborates a mechanism underlying SA homeostasis in plants, but also presents a promising strategy for engineering broad-spectrum and durable disease resistance in crops.


Asunto(s)
Resistencia a la Enfermedad/inmunología , Enfermedades de las Plantas/inmunología , Enfermedades de las Plantas/microbiología , Proteínas de Plantas/metabolismo , Homología de Secuencia de Aminoácido , Solanum lycopersicum/inmunología , Proteínas de Arabidopsis/metabolismo , Biocatálisis , Regulación de la Expresión Génica de las Plantas , Gentisatos/metabolismo , Solanum lycopersicum/genética , Solanum lycopersicum/crecimiento & desarrollo , Mutación/genética , Filogenia , Inmunidad de la Planta/genética , Proteínas de Plantas/genética , Plantas Modificadas Genéticamente , Ácido Salicílico/metabolismo , Transcriptoma/genética , Regulación hacia Arriba , Xanthomonas/fisiología
2.
Brain ; 145(12): 4489-4505, 2022 12 19.
Artículo en Inglés | MEDLINE | ID: mdl-35762829

RESUMEN

Early-onset (age < 65) Alzheimer's disease is associated with greater non-amnestic cognitive symptoms and neuropathological burden than late-onset disease. It is not fully understood whether these groups also differ in the associations between molecular pathology, neurodegeneration and cognitive performance. We studied amyloid-positive patients with early-onset (n = 60, mean age 58 ± 4, MMSE 21 ± 6, 58% female) and late-onset (n = 53, mean age 74 ± 6, MMSE 23 ± 5, 45% female) Alzheimer's disease who underwent neurological evaluation, neuropsychological testing, 11C-Pittsburgh compound B PET (amyloid-PET) and 18F-flortaucipir PET (tau-PET). 18F-fluorodeoxyglucose PET (brain glucose metabolism PET) was also available in 74% (n = 84) of participants. Composite scores for episodic memory, semantic memory, language, executive function and visuospatial domains were calculated based on cognitively unimpaired controls. Voxel-wise regressions evaluated correlations between PET biomarkers and cognitive scores and early-onset versus late-onset differences were tested with a PET × Age group interaction. Mediation analyses estimated direct and indirect (18F-fluorodeoxyglucose mediated) local associations between 18F-flortaucipir binding and cognitive scores in domain-specific regions of interest. We found that early-onset patients had higher 18F-flortaucipir binding in parietal, lateral temporal and lateral frontal cortex; more severe 18F-fluorodeoxyglucose hypometabolism in the precuneus and angular gyrus; and greater 11C-Pittsburgh compound B binding in occipital regions compared to late-onset patients. In our primary analyses, PET-cognition correlations did not meaningfully differ between age groups.18F-flortaucipir and 18F-fluorodeoxyglucose, but not 11C-Pittsburgh compound B, were significantly associated with cognition in expected domain-specific patterns in both age groups (e.g. left perisylvian/language, frontal/executive, occipital/visuospatial). 18F-fluorodeoxyglucose mediated the relationship between 18F-flortaucipir and cognition in both age groups across all domains except episodic memory in late-onset patients. Additional direct effects of 18F-flortaucipir were observed for executive function in all age groups, language in early-onset Alzheimer's disease and in the total sample and visuospatial function in the total sample. In conclusion, tau and neurodegeneration, but not amyloid, were similarly associated with cognition in both early and late-onset Alzheimer's disease. Tau had an association with cognition independent of neurodegeneration in language, executive and visuospatial functions in the total sample. Our findings support tau PET as a biomarker that captures both the clinical severity and molecular pathology specific to Alzheimer's disease across the broad spectrum of ages and clinical phenotypes in Alzheimer's disease.


Asunto(s)
Enfermedad de Alzheimer , Disfunción Cognitiva , Femenino , Masculino , Humanos , Enfermedad de Alzheimer/patología , Fluorodesoxiglucosa F18/metabolismo , Proteínas tau/metabolismo , Cognición , Encéfalo/patología , Amiloide/metabolismo , Proteínas Amiloidogénicas/metabolismo , Tomografía de Emisión de Positrones , Biomarcadores/metabolismo , Disfunción Cognitiva/patología
3.
Brain ; 145(2): 713-728, 2022 04 18.
Artículo en Inglés | MEDLINE | ID: mdl-34373896

RESUMEN

Posterior cortical hypometabolism measured with 18F-fluorodeoxyglucose (FDG)-PET is a well-known marker of Alzheimer's disease-related neurodegeneration, but its associations with underlying neuropathological processes are unclear. We assessed cross-sectionally the relative contributions of three potential mechanisms causing hypometabolism in the retrosplenial and inferior parietal cortices: local molecular (amyloid and tau) pathology and atrophy, distant factors including contributions from the degenerating medial temporal lobe or molecular pathology in functionally connected regions, and the presence of the apolipoprotein E (APOE) ε4 allele. Two hundred and thirty-two amyloid-positive cognitively impaired patients from two cohorts [University of California, San Francisco (UCSF), and Alzheimer's Disease Neuroimaging Initiative (ADNI)] underwent MRI and PET with FDG, amyloid-PET using 11C-Pittsburgh Compound-B, 18F-florbetapir or 18F-florbetaben, and 18F-flortaucipir tau-PET in 1 year. Standard uptake value ratios (SUVRs) were calculated using tracer-specific reference regions. Regression analyses were run within cohorts to identify variables associated with retrosplenial or inferior parietal FDG standard uptake value ratios. On average, ADNI patients were older and were less impaired than the UCSF patients. Regional patterns of hypometabolism were similar between cohorts, although there were cohort differences in regional grey matter atrophy. Local cortical thickness and tau-PET (but not amyloid-PET) were independently associated with both retrosplenial and inferior parietal FDG SUVRs (ΔR2 = 0.09 to 0.21) across cohorts in models that also included age and disease severity (local model). Including medial temporal lobe volume improved the retrosplenial FDG model in the ADNI cohort (ΔR2 = 0.04, P = 0.008) but not for the UCSF (ΔR2 < 0.01, P = 0.52), and did not improve the inferior parietal models (ΔR2 < 0.01, P > 0.37). Interaction analyses revealed that medial temporal volume was more strongly associated with retrosplenial FDG SUVRs at earlier disease stages (P = 0.06 in UCSF, P = 0.046 in ADNI). Exploratory analyses across the cortex confirmed overall associations between hypometabolism and local tau pathology and thickness and revealed associations between medial temporal degeneration and hypometabolism in retrosplenial, orbitofrontal and anterior cingulate cortices. Finally, our data did not support hypotheses of a detrimental effect of pathology in connected regions or of an effect of the APOE ε4 allele in impaired participants. Overall, in two independent groups of patients at symptomatic stages of Alzheimer's disease, cortical hypometabolism mainly reflected structural neurodegeneration and tau, but not amyloid, pathology.


Asunto(s)
Enfermedad de Alzheimer , Disfunción Cognitiva , Enfermedad de Alzheimer/diagnóstico por imagen , Enfermedad de Alzheimer/genética , Amiloide/metabolismo , Apolipoproteína E4/genética , Atrofia , Encéfalo/metabolismo , Disfunción Cognitiva/diagnóstico por imagen , Disfunción Cognitiva/genética , Fluorodesoxiglucosa F18 , Humanos , Imagen por Resonancia Magnética , Tomografía de Emisión de Positrones/métodos , Proteínas tau/metabolismo
4.
Ann Neurol ; 89(2): 389-401, 2021 02.
Artículo en Inglés | MEDLINE | ID: mdl-33219525

RESUMEN

OBJECTIVE: The purpose of this study was to compare the diagnostic accuracy of antemortem 11 C-Pittsburgh compound B (PIB) and 18 F-fluorodeoxyglucose (FDG) positron emission tomography (PET) versus autopsy diagnosis in a heterogenous sample of patients. METHODS: One hundred one participants underwent PIB and FDG PET during life and neuropathological assessment. PET scans were visually interpreted by 3 raters blinded to clinical information. PIB PET was rated as positive or negative for cortical retention, whereas FDG scans were read as showing an Alzheimer disease (AD) or non-AD pattern. Neuropathological diagnoses were assigned using research criteria. Majority visual reads were compared to intermediate-high AD neuropathological change (ADNC). RESULTS: One hundred one participants were included (mean age = 67.2 years, 41 females, Mini-Mental State Examination = 21.9, PET-to-autopsy interval = 4.4 years). At autopsy, 32 patients showed primary AD, 56 showed non-AD neuropathology (primarily frontotemporal lobar degeneration [FTLD]), and 13 showed mixed AD/FTLD pathology. PIB showed higher sensitivity than FDG for detecting intermediate-high ADNC (96%, 95% confidence interval [CI] = 89-100% vs 80%, 95% CI = 68-92%, p = 0.02), but equivalent specificity (86%, 95% CI = 76-95% vs 84%, 95% CI = 74-93%, p = 0.80). In patients with congruent PIB and FDG reads (77/101), combined sensitivity was 97% (95% CI = 92-100%) and specificity was 98% (95% CI = 93-100%). Nine of 24 patients with incongruent reads were found to have co-occurrence of AD and non-AD pathologies. INTERPRETATION: In our sample enriched for younger onset cognitive impairment, PIB-PET had higher sensitivity than FDG-PET for intermediate-high ADNC, with similar specificity. When both modalities are congruent, sensitivity and specificity approach 100%, whereas mixed pathology should be considered when PIB and FDG are incongruent. ANN NEUROL 2021;89:389-401.


Asunto(s)
Enfermedad de Alzheimer/diagnóstico por imagen , Compuestos de Anilina , Encéfalo/diagnóstico por imagen , Fluorodesoxiglucosa F18 , Demencia Frontotemporal/diagnóstico por imagen , Placa Amiloide/diagnóstico por imagen , Tomografía de Emisión de Positrones/métodos , Radiofármacos , Tiazoles , Adulto , Anciano , Anciano de 80 o más Años , Enfermedad de Alzheimer/metabolismo , Enfermedad de Alzheimer/patología , Péptidos beta-Amiloides/metabolismo , Autopsia , Encéfalo/metabolismo , Encéfalo/patología , Proteínas de Unión al ADN/metabolismo , Femenino , Demencia Frontotemporal/metabolismo , Demencia Frontotemporal/patología , Degeneración Lobar Frontotemporal/diagnóstico por imagen , Degeneración Lobar Frontotemporal/metabolismo , Degeneración Lobar Frontotemporal/patología , Humanos , Masculino , Persona de Mediana Edad , Enfermedad de Pick/diagnóstico por imagen , Enfermedad de Pick/metabolismo , Enfermedad de Pick/patología , Placa Amiloide/metabolismo , Placa Amiloide/psicología , Sensibilidad y Especificidad , Proteínas tau/metabolismo
5.
Cereb Cortex ; 31(1): 1-14, 2021 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-32808011

RESUMEN

A deeper understanding of the spatial relationships of ß-amyloid (Aß), tau, and neurodegeneration in Alzheimer's disease (AD) could provide insight into pathogenesis and clinical trial design. We included 81 amyloid-positive patients (age 64.4 ± 9.5) diagnosed with AD dementia or mild cognitive impairment due to AD and available 11C-PiB (PIB), 18F-Flortaucipir (FTP),18F-FDG-PET, and 3T-MRI, and 31 amyloid-positive, cognitively normal participants (age 77.3 ± 6.5, no FDG-PET). W-score voxel-wise deviation maps were created and binarized for each imaging-modality (W > 1.64, P < 0.05) adjusting for age, sex, and total intracranial volume (sMRI-only) using amyloid-negative cognitively normal adults. For symptomatic patients, FDG-PET and atrophy W-maps were combined into neurodegeneration maps (ND). Aß-pathology showed the greatest proportion of cortical gray matter suprathreshold voxels (spatial extent) for both symptomatic and asymptomatic participants (median 94-55%, respectively), followed by tau (79-11%) and neurodegeneration (41-3%). Amyloid > tau > neurodegeneration was the most frequent hierarchy for both groups (79-77%, respectively), followed by tau > amyloid > neurodegeneration (13-10%) and amyloid > neurodegeneration > tau (6-13%). For symptomatic participants, most abnormal voxels were PIB+/FTP+/ND- (median 35%), and the great majority of ND+ voxels (91%) colocalized with molecular pathology. Amyloid spatially exceeded tau and neurodegeneration, with individual heterogeneities. Molecular pathology and neurodegeneration showed a progressive overlap along AD course, indicating shared vulnerabilities or synergistic toxic mechanisms.


Asunto(s)
Enfermedad de Alzheimer/patología , Enfermedades Neurodegenerativas/patología , Anciano , Anciano de 80 o más Años , Enfermedad de Alzheimer/diagnóstico por imagen , Enfermedad de Alzheimer/metabolismo , Precursor de Proteína beta-Amiloide/genética , Precursor de Proteína beta-Amiloide/metabolismo , Disfunción Cognitiva/diagnóstico por imagen , Disfunción Cognitiva/metabolismo , Disfunción Cognitiva/patología , Femenino , Sustancia Gris/diagnóstico por imagen , Sustancia Gris/patología , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Enfermedades Neurodegenerativas/diagnóstico por imagen , Enfermedades Neurodegenerativas/metabolismo , Pruebas Neuropsicológicas , Patología Molecular , Tomografía de Emisión de Positrones , Proteínas tau/genética , Proteínas tau/metabolismo
6.
Eur J Nucl Med Mol Imaging ; 48(7): 2259-2271, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-33398408

RESUMEN

PURPOSE: To compare rates of tau biomarker positivity (T-status) per the 2018 Alzheimer's Disease (AD) Research Framework derived from [18F]flortaucipir (FTP) PET visual assessment, FTP quantification, and cerebrospinal fluid (CSF) phosphorylated Tau-181 (PTau181). METHODS: We included 351 subjects with varying clinical diagnoses from three cohorts with available FTP PET and CSF PTau181 within 18 months. T-status was derived from (1) FTP visual assessment by two blinded raters; (2) FTP standardized uptake value ratio (SUVR) quantification from a temporal meta-ROI (threshold: SUVR ≥1.27); and (3) Elecsys® Phospho-Tau (181P) CSF (Roche Diagnostics) concentrations (threshold: PTau181 ≥ 24.5 pg/mL). RESULTS: FTP visual reads yielded the highest rates of T+, while T+ by SUVR increased progressively from cognitively normal (CN) through mild cognitive impairment (MCI) and AD dementia. T+ designation by CSF PTau181 was intermediate between FTP visual reads and SUVR values in CN, similar to SUVR in MCI, and lower in AD dementia. Concordance in T-status between modality pairs ranged from 68 to 76% and varied by clinical diagnosis, being highest in patients with AD dementia. In discriminating Aß + MCI and AD subjects from healthy controls and non-AD participants, FTP visual assessment was most sensitive (0.96) but least specific (0.60). Specificity was highest with FTP SUVR (0.91) with sensitivity of 0.89. Sensitivity (0.73) and specificity (0.72) were balanced for PTau181. CONCLUSION: The choice of tau biomarker may differ by disease stage and research goals that seek to maximize sensitivity or specificity. Visual interpretations of tau PET enhance sensitivity compared to quantification alone, particularly in early disease stages.


Asunto(s)
Enfermedad de Alzheimer , Disfunción Cognitiva , Enfermedad de Alzheimer/diagnóstico por imagen , Péptidos beta-Amiloides , Biomarcadores , Disfunción Cognitiva/diagnóstico por imagen , Humanos , Tomografía de Emisión de Positrones , Proteínas tau
7.
Brain ; 143(11): 3477-3494, 2020 12 05.
Artículo en Inglés | MEDLINE | ID: mdl-33141172

RESUMEN

Few studies have evaluated the relationship between in vivo18F-flortaucipir PET and post-mortem pathology. We sought to compare antemortem 18F-flortaucipir PET to neuropathology in a consecutive series of patients with a broad spectrum of neurodegenerative conditions. Twenty patients were included [mean age at PET 61 years (range 34-76); eight female; median PET-to-autopsy interval of 30 months (range 4-59 months)]. Eight patients had primary Alzheimer's disease pathology, nine had non-Alzheimer tauopathies (progressive supranuclear palsy, corticobasal degeneration, argyrophilic grain disease, and frontotemporal lobar degeneration with MAPT mutations), and three had non-tau frontotemporal lobar degeneration. Using an inferior cerebellar grey matter reference, 80-100-min 18F-flortaucipir PET standardized uptake value ratio (SUVR) images were created. Mean SUVRs were calculated for progressive supranuclear palsy, corticobasal degeneration, and neurofibrillary tangle Braak stage regions of interest, and these values were compared to SUVRs derived from young, non-autopsy, cognitively normal controls used as a standard for tau negativity. W-score maps were generated to highlight areas of increased tracer retention compared to cognitively normal controls, adjusting for age as a covariate. Autopsies were performed blinded to PET results. There was excellent correspondence between areas of 18F-flortaucipir retention, on both SUVR images and W-score maps, and neurofibrillary tangle distribution in patients with primary Alzheimer's disease neuropathology. Patients with non-Alzheimer tauopathies and non-tau frontotemporal lobar degeneration showed a range of tracer retention that was less than Alzheimer's disease, though higher than age-matched, cognitively normal controls. Overall, binding across both tau-positive and tau-negative non-Alzheimer disorders did not reliably correspond with post-mortem tau pathology. 18F-flortaucipir SUVRs in subcortical regions were higher in autopsy-confirmed progressive supranuclear palsy and corticobasal degeneration than in controls, but were similar to values measured in Alzheimer's disease and tau-negative neurodegenerative pathologies. Quantification of 18F-flortaucipir SUVR images at Braak stage regions of interest reliably detected advanced Alzheimer's (Braak VI) pathology. However, patients with earlier Braak stages (Braak I-IV) did not show elevated tracer uptake in these regions compared to young, tau-negative controls. In summary, PET-to-autopsy comparisons confirm that 18F-flortaucipir PET is a reliable biomarker of advanced Braak tau pathology in Alzheimer's disease. The tracer cannot reliably differentiate non-Alzheimer tauopathies and may not detect early Braak stages of neurofibrillary tangle pathology.


Asunto(s)
Enfermedad de Alzheimer/diagnóstico por imagen , Enfermedades Neurodegenerativas/diagnóstico por imagen , Tomografía de Emisión de Positrones/métodos , Adulto , Anciano , Enfermedad de Alzheimer/patología , Autopsia , Carbolinas , Progresión de la Enfermedad , Femenino , Degeneración Lobar Frontotemporal/diagnóstico por imagen , Degeneración Lobar Frontotemporal/patología , Sustancia Gris/diagnóstico por imagen , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Enfermedades Neurodegenerativas/patología , Ovillos Neurofibrilares/patología , Radiofármacos , Parálisis Supranuclear Progresiva/diagnóstico por imagen , Parálisis Supranuclear Progresiva/patología , Tauopatías/diagnóstico por imagen , Tauopatías/patología
8.
Proc Natl Acad Sci U S A ; 115(46): E10979-E10987, 2018 11 13.
Artículo en Inglés | MEDLINE | ID: mdl-30373842

RESUMEN

Effector-triggered immunity (ETI) in plants involves a large family of nucleotide-binding leucine-rich repeat (NLR) immune receptors, including Toll/IL-1 receptor-NLRs (TNLs) and coiled-coil NLRs (CNLs). Although various NLR immune receptors are known, a mechanistic understanding of NLR function in ETI remains unclear. The TNL Recognition of XopQ 1 (Roq1) recognizes the effectors XopQ and HopQ1 from Xanthomonas and Pseudomonas, respectively, which activates resistance to Xanthomonas euvesicatoria and Xanthomonas gardneri in an Enhanced Disease Susceptibility 1 (EDS1)-dependent way in Nicotiana benthamiana In this study, we found that the N. benthamiana N requirement gene 1 (NRG1), a CNL protein required for the tobacco TNL protein N-mediated resistance to tobacco mosaic virus, is also essential for immune signaling [including hypersensitive response (HR)] triggered by the TNLs Roq1 and Recognition of Peronospora parasitica 1 (RPP1), but not by the CNLs Bs2 and Rps2, suggesting that NRG1 may be a conserved key component in TNL signaling pathways. Besides EDS1, Roq1 and NRG1 are necessary for resistance to Xanthomonas and Pseudomonas in N. benthamiana NRG1 functions downstream of Roq1 and EDS1 and physically associates with EDS1 in mediating XopQ-Roq1-triggered immunity. Moreover, RNA sequencing analysis showed that XopQ-triggered gene-expression profile changes in N. benthamiana were almost entirely mediated by Roq1 and EDS1 and were largely regulated by NRG1. Overall, our study demonstrates that NRG1 is a key component that acts downstream of EDS1 to mediate various TNL signaling pathways, including Roq1 and RPP1-mediated HR, resistance to Xanthomonas and Pseudomonas, and XopQ-regulated transcriptional changes in N. benthamiana.


Asunto(s)
Nicotiana/genética , Nicotiana/metabolismo , Subgrupos de Linfocitos B/metabolismo , Proteínas de Unión al ADN , Proteínas Repetidas Ricas en Leucina , Proteínas NLR/metabolismo , Neurregulina-1/genética , Neurregulina-1/fisiología , Enfermedades de las Plantas , Inmunidad de la Planta , Proteínas de Plantas/genética , Dominios Proteicos , Proteínas/genética , Pseudomonas , Transducción de Señal , Transcriptoma , Xanthomonas
9.
Ann Neurol ; 85(2): 229-240, 2019 02.
Artículo en Inglés | MEDLINE | ID: mdl-30597624

RESUMEN

OBJECTIVE: To determine the rate of tau accumulation in healthy older adults (OA) and patients with Alzheimer disease (AD), as well as the relationship of tau accumulation to cortical atrophy. METHODS: Two longitudinal flortaucipir (FTP) positron emission tomography (PET) and magnetic resonance imaging (MRI) scans were acquired from 42 OA (21 Pittsburg compound B [PiB]+ , age = 77.6 ± 4.6 years, 25 female [F]/17 male [M]) and 19 PiB+ patients with AD (age = 63.1 ± 10.3 years, 12 F/7 M) over 1 to 3 years of follow-up. FTP change, structural MRI measures of atrophy, and cross-modal correlations were examined on a voxelwise level. Regional annual percentage change in FTP was also calculated. RESULTS: Voxelwise FTP change in AD showed the greatest increases in lateral and medial frontal lobes. Atrophy over the same interval was more widespread and included posteromedial cortical areas, where tau accumulation rates were lower. In OA, FTP binding increased in bilateral temporal lobe and retrosplenial cortex, accompanied by atrophy in the same regions. There were no associations between voxelwise change in FTP and sex, PiB, or APOE. Regional FTP significantly increased at follow-up in OA and patients with AD. Mixed effects models showed greater FTP increases in AD compared to OA, and no differences within OA based on PiB status. INTERPRETATION: Our findings indicate that tau accumulates even in amyloid-negative healthy OA and this process can be measured with in vivo tau-PET. In OA, tau accumulation and atrophy share a similar topography. In AD, tau increases more rapidly and accumulation occurs in frontal regions that are not yet undergoing significant atrophy. Ann Neurol 2019; 1-12 ANN NEUROL 2019;85:229-240.


Asunto(s)
Envejecimiento/metabolismo , Enfermedad de Alzheimer/diagnóstico por imagen , Corteza Cerebral/diagnóstico por imagen , Proteínas tau/metabolismo , Anciano , Anciano de 80 o más Años , Enfermedad de Alzheimer/metabolismo , Enfermedad de Alzheimer/patología , Compuestos de Anilina , Atrofia , Encéfalo/diagnóstico por imagen , Encéfalo/patología , Carbolinas , Estudios de Casos y Controles , Corteza Cerebral/patología , Medios de Contraste , Femenino , Humanos , Estudios Longitudinales , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Imagen Multimodal , Tamaño de los Órganos , Tomografía de Emisión de Positrones , Tiazoles
10.
Chemistry ; 26(56): 12818-12830, 2020 Oct 06.
Artículo en Inglés | MEDLINE | ID: mdl-32939912

RESUMEN

Due to their interactions with C-type lectin receptors (CLRs), glycans from the helminth Schistosoma mansoni represent promising leads for treatment of autoimmune diseases, allergies or cancer. We chemo-enzymatically synthesized nine O-glycans based on the two predominant O-glycan cores observed in the infectious stages of schistosomiasis, the mucin core 2 and the S. mansoni core. The O-glycans were fucosylated next to a selection of N-glycans directly on a microarray slide using a recombinant fucosyltransferase and GDP-fucose or GDP-6-azidofucose as donor. Binding assays with fluorescently labelled human CLRs DC-SIGN, DC-SIGNR and MGL revealed the novel O-glycan O8 as the best ligand for MGL from our panel. Significant binding to DC-SIGN was also found for azido-fucosylated glycans. Contrasting binding specificities were observed between the monovalent carbohydrate recognition domain (CRD) and the tetravalent extracellular domain (ECD) of DC-SIGNR.


Asunto(s)
Receptores de Superficie Celular/metabolismo , Moléculas de Adhesión Celular , Humanos , Lectinas Tipo C , Ligandos , Polisacáridos
12.
Soins ; 69(884): 22-25, 2024 Apr.
Artículo en Francés | MEDLINE | ID: mdl-38614514

RESUMEN

Improved recovery after surgery leads to a significant reduction in postoperative morbidity, but this is concentrated in the intra- and postoperative periods. Prehabilitation complements this, by taking charge of the pre-operative phase. Its aim is to improve pre-operative functional capacity and physical, nutritional and psychosocial status. Interdisciplinary collaboration is a key element of this integrated approach.


Asunto(s)
Recuperación Mejorada Después de la Cirugía , Ejercicio Preoperatorio , Humanos , Pacientes
13.
Patient Educ Couns ; 123: 108199, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38359589

RESUMEN

OBJECTIVE: To examine sources and perceived credibility of child nutrition information by maternal health literacy. METHODS: US mothers of children (0-12 years) who used social media regularly (N = 340) completed an online survey. Health literacy was assessed using the Newest Vital Sign. Child nutrition information sources and perceived credibility of sources were compared by health literacy using logistic and quantile regression models. RESULTS: Seventeen percent of mothers had limited health literacy. Compared to mothers with adequate health literacy, those with limited health literacy were more likely to get child nutrition information from siblings, extended family, dietitians, doctors, nurse practitioners, or physician assistants, and government agencies, and less likely to get information from Facebook. Mothers with limited health literacy rated information from parents, friends, Facebook, and Instagram as more credible than mothers with adequate health literacy. While perceived credibility of information from doctors, nurse practitioners, or physician assistants was high overall, mothers with limited health literacy perceived information from these health care providers as less credible. CONCLUSIONS: Sources of child nutrition information and perceived credibility differ by maternal health literacy. PRACTICE IMPLICATIONS: Pediatric providers are encouraged to refer parents to engaging resources that provide evidence-based child nutrition information.


Asunto(s)
Alfabetización en Salud , Nutricionistas , Medios de Comunicación Sociales , Femenino , Humanos , Niño , Madres , Encuestas y Cuestionarios
14.
J Clin Med ; 13(9)2024 Apr 25.
Artículo en Inglés | MEDLINE | ID: mdl-38731055

RESUMEN

Background: to examine factors associated with cardiac evaluation and associations between cardiac test abnormalities and clinical outcomes in patients with acute brain injury (ABI) due to acute ischemic stroke (AIS), spontaneous subarachnoid hemorrhage (SAH), spontaneous intracerebral hemorrhage (sICH), and traumatic brain injury (TBI) requiring neurocritical care. Methods: In a cohort of patients ≥18 years, we examined the utilization of electrocardiography (ECG), beta-natriuretic peptide (BNP), cardiac troponin (cTnI), and transthoracic echocardiography (TTE). We investigated the association between cTnI, BNP, sex-adjusted prolonged QTc interval, low ejection fraction (EF < 40%), all-cause mortality, death by neurologic criteria (DNC), transition to comfort measures only (CMO), and hospital discharge to home using univariable and multivariable analysis (adjusted for age, sex, race/ethnicity, insurance carrier, pre-admission cardiac disorder, ABI type, admission Glasgow Coma Scale Score, mechanical ventilation, and intracranial pressure [ICP] monitoring). Results: The final sample comprised 11,822 patients: AIS (46.7%), sICH (18.5%), SAH (14.8%), and TBI (20.0%). A total of 63% (n = 7472) received cardiac workup, which increased over nine years (p < 0.001). A cardiac investigation was associated with increased age, male sex (aOR 1.16 [1.07, 1.27]), non-white ethnicity (aOR), non-commercial insurance (aOR 1.21 [1.09, 1.33]), pre-admission cardiac disorder (aOR 1.21 [1.09, 1.34]), mechanical ventilation (aOR1.78 [1.57, 2.02]) and ICP monitoring (aOR1.68 [1.49, 1.89]). Compared to AIS, sICH (aOR 0.25 [0.22, 0.29]), SAH (aOR 0.36 [0.30, 0.43]), and TBI (aOR 0.19 [0.17, 0.24]) patients were less likely to receive cardiac investigation. Patients with troponin 25th-50th quartile (aOR 1.65 [1.10-2.47]), troponin 50th-75th quartile (aOR 1.79 [1.22-2.63]), troponin >75th quartile (aOR 2.18 [1.49-3.17]), BNP 50th-75th quartile (aOR 2.86 [1.28-6.40]), BNP >75th quartile (aOR 4.54 [2.09-9.85]), prolonged QTc (aOR 3.41 [2.28; 5.30]), and EF < 40% (aOR 2.47 [1.07; 5.14]) were more likely to be DNC. Patients with troponin 50th-75th quartile (aOR 1.77 [1.14-2.73]), troponin >75th quartile (aOR 1.81 [1.18-2.78]), and prolonged QTc (aOR 1.71 [1.39; 2.12]) were more likely to be associated with a transition to CMO. Patients with prolonged QTc (aOR 0.66 [0.58; 0.76]) were less likely to be discharged home. Conclusions: This large, single-center study demonstrates low rates of cardiac evaluations in TBI, SAH, and sICH compared to AIS. However, there are strong associations between electrocardiography, biomarkers of cardiac injury and heart failure, and echocardiography findings on clinical outcomes in patients with ABI. Findings need validation in a multicenter cohort.

15.
Nanotechnology ; 23(27): 275606, 2012 Jul 11.
Artículo en Inglés | MEDLINE | ID: mdl-22710608

RESUMEN

We have developed a very simple approach for preparing physically embedded gold cores in a temperature-responsive hydrogel polymer nanoparticle under fluorescent light irradiation. The complete encapsulation of the multiple gold core nanoparticles is confirmed by the catalytic reduction of 4-nitrophenol, whose reactivity is significantly retarded above the lower critical solution temperature (LSCT) due to the deswelled polymer structure; its increased hydrophobicity slows the access of hydrophilic reactants to the cores. Since these gold cores are physically embedded in the polymer nanoparticles, further growth of the cores is reliably achieved in situ under light irradiation. Interestingly, the resulting composite nanoparticles exhibit reversible solution color changes as well as absorption bands from the visible to near-IR regions below and above the LSCT.


Asunto(s)
Colorimetría/métodos , Oro/química , Hidrogeles/química , Nanoestructuras/química , Nanoestructuras/ultraestructura , Termografía/métodos , Calor , Sustancias Macromoleculares/química , Ensayo de Materiales , Conformación Molecular , Tamaño de la Partícula , Refractometría , Propiedades de Superficie
16.
Clin Psychol Rev ; 94: 102159, 2022 06.
Artículo en Inglés | MEDLINE | ID: mdl-35483274

RESUMEN

Posttraumatic growth (PTG) has captivated the attention of clinicians and researchers over the past three decades. However, accumulating evidence suggests that individuals' self-reports of PTG may be cognitively biased. In the current systematic review and meta-analysis, we aimed to investigate the relation between cognitive biases and perceived PTG. In line with existing theory on cognitive biases that may lead to illusory perceived PTG, we examined the following cognitive biases: defensiveness, memory bias, downward comparison bias, social desirability bias, positive attention bias, and growth beliefs. Forty-seven studies met criteria for inclusion in this review and 66 separate effects were coded for meta-analyses. Results indicated that cognitive biases were related to perceived PTG, with variation by type of cognitive bias. Moderator analyses revealed that downward comparison bias, positive attention bias, and growth beliefs exhibited stronger relations with perceived PTG than did defensiveness, memory bias, and social desirability bias. Further, subgroup analyses explored effects by type of cognitive bias and characteristics of cognitive bias measurements. The current study suggests that cognitive biases may have a role in individuals' perceptions of their PTG. This contributes to theory on the origins of illusory perceptions of PTG and provides direction for improvements to the measurement of PTG and clinical approaches to PTG.


Asunto(s)
Sesgo Atencional , Crecimiento Psicológico Postraumático , Trastornos por Estrés Postraumático , Adaptación Psicológica , Sesgo , Cognición , Humanos
17.
Semin Vasc Surg ; 35(1): 16-34, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-35501038

RESUMEN

Thoracic aortic aneurysm and dissection are complex diagnoses that require management by multidisciplinary providers using a variety of medical therapies, surgical interventions, and lifestyle modifications. Pharmacological agents, such as ß-blockers (atenolol) and angiotensin II type 1 receptor blockers (losartan), have been mainstay treatments for several years, and research from the past decade has continued to evaluate these and other medication classes to further improve patient morbidity and mortality. Combination ß- and renin-aldosterone-angiotensin blockade, statins, metformin, antioxidants, and vitamins have been evaluated as therapeutics in both thoracic and abdominal aortic aneurysms, as well as the effects of various antibiotics (ie, fluoroquinolones and tetracyclines) and benefits of lifestyle modifications (eg, diet and exercise) and enhanced patient-centered care and treatment adherence. In addition, as our understanding of the genetic, biochemical, and pathophysiological mechanisms behind these diseases expands, so do potential targets for future therapeutic research (eg, interleukins, matrix metalloproteases, and mast cells). This review incorporates the major meta-analyses, systematic and generalized reviews, and clinical trials published from 2010 through 2021 that focus on these topics in thoracic aortic aneurysms (and abdominal aneurysms when thoracic literature is scarce). Several key ongoing clinical trials, case studies, and in vivo/in vitro studies are also mentioned. Furthermore, we discuss current gaps in the literature and the abundance of clinical evidence for some interventions in abdominal aneurysms with few thoracic correlates, thus indicating a need for investigation of these subjects in the latter.


Asunto(s)
Aneurisma de la Aorta Abdominal , Aneurisma de la Aorta Torácica , Aneurisma de la Aorta Abdominal/diagnóstico por imagen , Aneurisma de la Aorta Abdominal/tratamiento farmacológico , Aneurisma de la Aorta Torácica/diagnóstico por imagen , Aneurisma de la Aorta Torácica/tratamiento farmacológico , Humanos
18.
Surgery ; 172(4): 1210-1219, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-35864049

RESUMEN

BACKGROUND: The diagnosis of low potential malignant diseases is increasingly frequent, and laparoscopic central pancreatectomy can be indicated in these patients. Laparoscopic central pancreatectomy that usually preserves the splenic vessels results in a low risk of new-onset diabetes but high morbidity, mainly due to postoperative pancreatic fistula and postpancreatectomy hemorrhage. In this study, we evaluated the short and long-term complications after laparoscopic central pancreatectomy with splenic vessel resection. METHODS: This retrospective single-center cohort study included 650 laparoscopic pancreatic resections from 2008 to 2020 with 84 laparoscopic central pancreatectomy; 15 laparoscopic central pancreatectomy with splenic vessel resection; and 69 laparoscopic central pancreatectomy with preservation of the splenic vessels. Pancreaticogastrostomy was routinely performed, and the patients were discharged after complications had been treated. The 15 laparoscopic central pancreatectomy with splenic vessel resection were matched for age, sex, body mass index, and tumor characteristics [1:2] and compared with 30 laparoscopic central pancreatectomy with the preservation of the splenic vessels. RESULTS: In the laparoscopic central pancreatectomy with splenic vessel resection group, resection of splenic vessels was performed due to tumoral or inflammatory adhesions (n = 11) or accidental vascular injury (n = 4). The demographic characteristics of the groups were similar. Tumors were larger in the laparoscopic central pancreatectomy with splenic vessel resection group (40 vs 21 mm; P = .008), and right transection on the body of the pancreas (53% vs 13%; P = .01) was more frequent. There were no differences in the characteristics of the pancreas (Wirsung duct size or consistency). The median operative time (minutes) was longer in the laparoscopic central pancreatectomy with splenic vessel resection group than in the laparoscopic central pancreatectomy with preservation of the splenic vessels group (210 vs 180, respectively; P = .15) with more blood loss (100 mL vs 50 mL, respectively; P = .012). The lengths (mm) of the resected pancreas and remnant distal pancreas in the 2 groups were 65 vs 50 (P = .053) and 40 vs 65 (P = .006), respectively. There were no differences in postoperative mortality (0% vs 3%; P = .47), grade B-C postoperative pancreatic fistula (27% vs 27%; P = 1), reintervention (7% vs 13%; P = .50), grade B-C postpancreatectomy hemorrhage (0% vs 13%; P = .13), length of hospital stay (20 days vs 22 days; P = .15), or new-onset diabetes (7% vs 10%; P = .67) between the 2 groups. CONCLUSION: Laparoscopic central pancreatectomy with splenic vessel resection is a safe technical modification of central pancreatectomy that does not prevent preservation of the distal pancreas and does not influence postoperative pancreatic fistula or endocrine insufficiency. Furthermore, it could reduce the risk of postpancreatectomy hemorrhage.


Asunto(s)
Laparoscopía , Neoplasias Pancreáticas , Estudios de Cohortes , Humanos , Laparoscopía/efectos adversos , Laparoscopía/métodos , Páncreas/patología , Páncreas/cirugía , Pancreatectomía/efectos adversos , Pancreatectomía/métodos , Fístula Pancreática/etiología , Fístula Pancreática/prevención & control , Fístula Pancreática/cirugía , Neoplasias Pancreáticas/patología , Neoplasias Pancreáticas/cirugía , Complicaciones Posoperatorias/epidemiología , Complicaciones Posoperatorias/etiología , Complicaciones Posoperatorias/prevención & control , Estudios Retrospectivos , Resultado del Tratamiento
19.
Obes Sci Pract ; 8(6): 811-815, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36483120

RESUMEN

Objective: Behavioral weight management trials are traditionally conducted in-person. The COVID-19 shutdown halted in-person operations, forcing investigators to develop new methods for remote treatment and assessment delivery without additional funding for website development or remote equipment. This study examined the feasibility and acceptability of remote procedures from an ongoing weight management trial impacted by COVID-19. Methods: Using a quasi-experimental longitudinal design, in-person (pre-COVID) and remote (COVID) treatment and assessment procedures were used. Attendance at in-person versus remote (videoconference) treatment sessions was compared. Acceptability of treatment modalities (in-person vs. remote) was examined via self-report. Validity and reliability were assessed on bathroom scales. Attendance at remote (videoconference + mailed, scales) versus in-person assessment sessions was compared. Finally, exploratory analyses were conducted to determine whether participant characteristics moderated the effects. Results: Remote treatment attendance was significantly better than in-person. Overall, there was no significant difference in modality preference. However, Hispanic (vs. non-Hispanic) individuals had greater preference for remote options and attended more remote treatment sessions. Bathroom scales demonstrated excellent validity and reliability. Adherence to remote and in-person assessment sessions was similar. Conclusions: COVID-19 has provided an opportunity to rethink how we conduct research. Results herein establish an evidence-base to support a paradigm shift to remote clinical trial procedures. Such a shift may enhance diversity in clinical trials.

20.
J Cereb Blood Flow Metab ; 41(9): 2329-2343, 2021 09.
Artículo en Inglés | MEDLINE | ID: mdl-33691512

RESUMEN

We used 18F-FDG-PET to investigate the frequency of crossed cerebellar diaschisis (CCD) in 197 patients with various syndromes associated with neurodegenerative diseases. In a subset of 117 patients, we studied relationships between CCD and cortical asymmetry of Alzheimer's pathology (ß-amyloid (11C-PIB) and tau (18F-Flortaucipir)). PET images were processed using MRIs to derive parametric SUVR images and define regions of interest. Indices of asymmetry were calculated in the cerebral cortex, basal ganglia and cerebellar cortex. Across all patients, cerebellar 18F-FDG asymmetry was associated with reverse asymmetry of 18F-FDG in the cerebral cortex (especially frontal and parietal areas) and basal ganglia. Based on our operational definition (cerebellar asymmetry >3% with contralateral supratentorial hypometabolism), significant CCD was present in 47/197 (24%) patients and was most frequent in corticobasal syndrome and semantic and logopenic variants of primary progressive aphasia. In ß-amyloid-positive patients, mediation analyses showed that 18F-Flortaucipir cortical asymmetry was associated with cerebellar 18F-FDG asymmetry, but that cortical 18F-FDG asymmetry mediated this relationship. Analysis of 18F-FDG-SUVR values suggested that CCD might also occur in the absence of frank cerebellar 18F-FDG asymmetry due to symmetrical supratentorial degeneration resulting in a bilateral diaschisis process.


Asunto(s)
Cerebelo/fisiopatología , Fluorodesoxiglucosa F18/uso terapéutico , Enfermedades Neurodegenerativas/sangre , Enfermedades Neurodegenerativas/fisiopatología , Tomografía de Emisión de Positrones/métodos , Radiofármacos/efectos adversos , Adulto , Anciano , Anciano de 80 o más Años , Humanos , Persona de Mediana Edad , Enfermedades Neurodegenerativas/diagnóstico por imagen , Estudios Retrospectivos , Síndrome , Adulto Joven
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