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1.
Cell ; 176(1-2): 56-72.e15, 2019 01 10.
Artículo en Inglés | MEDLINE | ID: mdl-30612743

RESUMEN

Local translation regulates the axonal proteome, playing an important role in neuronal wiring and axon maintenance. How axonal mRNAs are localized to specific subcellular sites for translation, however, is not understood. Here we report that RNA granules associate with endosomes along the axons of retinal ganglion cells. RNA-bearing Rab7a late endosomes also associate with ribosomes, and real-time translation imaging reveals that they are sites of local protein synthesis. We show that RNA-bearing late endosomes often pause on mitochondria and that mRNAs encoding proteins for mitochondrial function are translated on Rab7a endosomes. Disruption of Rab7a function with Rab7a mutants, including those associated with Charcot-Marie-Tooth type 2B neuropathy, markedly decreases axonal protein synthesis, impairs mitochondrial function, and compromises axonal viability. Our findings thus reveal that late endosomes interact with RNA granules, translation machinery, and mitochondria and suggest that they serve as sites for regulating the supply of nascent pro-survival proteins in axons.


Asunto(s)
Endosomas/fisiología , Biosíntesis de Proteínas/fisiología , Proteínas de Unión al GTP rab/metabolismo , Animales , Axones/metabolismo , Endosomas/metabolismo , Mitocondrias/genética , Mitocondrias/metabolismo , ARN/metabolismo , ARN Mensajero/metabolismo , ARN Mensajero/fisiología , Células Ganglionares de la Retina/metabolismo , Células Ganglionares de la Retina/fisiología , Ribosomas/metabolismo , Proteínas de Xenopus/metabolismo , Xenopus laevis/metabolismo , Proteínas de Unión al GTP rab/genética , Proteínas de Unión al GTP rab/fisiología , Proteínas de Unión a GTP rab7
2.
Cell ; 152(1-2): 13-4, 2013 Jan 17.
Artículo en Inglés | MEDLINE | ID: mdl-23332742

RESUMEN

Drosophila neural progenitor cells are competent to give rise to certain neuronal cell types only during a limited period of time. Kohwi et al. link the termination of early competence to changes in subnuclear organization of chromatin.

3.
Circulation ; 149(4): 305-316, 2024 01 23.
Artículo en Inglés | MEDLINE | ID: mdl-38047387

RESUMEN

BACKGROUND: It is unknown whether dietary intake of polyunsaturated fatty acids (PUFA) modifies the cardiovascular disease (CVD) risk associated with a family history of CVD. We assessed interactions between biomarkers of low PUFA intake and a family history in relation to long-term CVD risk in a large consortium. METHODS: Blood and tissue PUFA data from 40 885 CVD-free adults were assessed. PUFA levels ≤25th percentile were considered to reflect low intake of linoleic, alpha-linolenic, and eicosapentaenoic/docosahexaenoic acids (EPA/DHA). Family history was defined as having ≥1 first-degree relative who experienced a CVD event. Relative risks with 95% CI of CVD were estimated using Cox regression and meta-analyzed. Interactions were assessed by analyzing product terms and calculating relative excess risk due to interaction. RESULTS: After multivariable adjustments, a significant interaction between low EPA/DHA and family history was observed (product term pooled RR, 1.09 [95% CI, 1.02-1.16]; P=0.01). The pooled relative risk of CVD associated with the combined exposure to low EPA/DHA, and family history was 1.41 (95% CI, 1.30-1.54), whereas it was 1.25 (95% CI, 1.16-1.33) for family history alone and 1.06 (95% CI, 0.98-1.14) for EPA/DHA alone, compared with those with neither exposure. The relative excess risk due to interaction results indicated no interactions. CONCLUSIONS: A significant interaction between biomarkers of low EPA/DHA intake, but not the other PUFA, and a family history was observed. This novel finding might suggest a need to emphasize the benefit of consuming oily fish for individuals with a family history of CVD.


Asunto(s)
Enfermedades Cardiovasculares , Ácidos Grasos Omega-3 , Animales , Enfermedades Cardiovasculares/diagnóstico , Enfermedades Cardiovasculares/epidemiología , Enfermedades Cardiovasculares/genética , Factores de Riesgo , Ácidos Docosahexaenoicos , Biomarcadores
4.
Proteins ; 92(6): 693-704, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38179877

RESUMEN

Human acyl protein thioesterases (APTs) catalyze the depalmitoylation of S-acylated proteins attached to the plasma membrane, facilitating reversible cycles of membrane anchoring and detachment. We previously showed that a bacterial APT homologue, FTT258 from the gram-negative pathogen Francisella tularensis, exists in equilibrium between a closed and open state based on the structural dynamics of a flexible loop overlapping its active site. Although the structural dynamics of this loop are not conserved in human APTs, the amino acid sequence of this loop is highly conserved, indicating essential but divergent functions for this loop in human APTs. Herein, we investigated the role of this loop in regulating the catalytic activity, ligand binding, and protein folding of human APT1, a depalmitoylase connected with cancer, immune, and neurological signaling. Using a combination of substitutional analysis with kinetic, structural, and biophysical characterization, we show that even in its divergent structural location in human APT1 that this loop still regulates the catalytic activity of APT1 through contributions to ligand binding and substrate positioning. We confirmed previously known roles for multiple residues (Phe72 and Ile74) in substrate binding and catalysis while adding new roles in substrate selectivity (Pro69), in catalytic stabilization (Asp73 and Ile75), and in transitioning between the membrane binding ß-tongue and substrate-binding loops (Trp71). Even conservative substitution of this tryptophan (Trp71) fulcrum led to complete loss of catalytic activity, a 13°C decrease in total protein stability, and drastic drops in ligand affinity, indicating that the combination of the size, shape, and aromaticity of Trp71 are essential to the proper structure of APT1. Mixing buried hydrophobic surface area with contributions to an exposed secondary surface pocket, Trp71 represents a previously unidentified class of essential tryptophans within α/ß hydrolase structure and a potential allosteric binding site within human APTs.


Asunto(s)
Dominio Catalítico , Unión Proteica , Pliegue de Proteína , Tioléster Hidrolasas , Humanos , Tioléster Hidrolasas/química , Tioléster Hidrolasas/metabolismo , Tioléster Hidrolasas/genética , Ligandos , Modelos Moleculares , Secuencia de Aminoácidos , Cinética , Secuencia Conservada , Estabilidad de Enzimas , Francisella tularensis/enzimología , Francisella tularensis/metabolismo , Francisella tularensis/química , Cristalografía por Rayos X , Especificidad por Sustrato
5.
Stroke ; 55(3): 541-547, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38299346

RESUMEN

BACKGROUND: Nontraumatic intracerebral hemorrhage (ICH) is independently associated with a long-term increased risk of major arterial ischemic events. While the relationship between ICH location and ischemic risk has been studied, whether hematoma volume influences this risk is poorly understood. METHODS: We pooled individual patient data from the MISTIE III (Minimally Invasive Surgery Plus Alteplase for Intracerebral Hemorrhage Evacuation Phase 3) and the ATACH-2 (Antihypertensive Treatment of Acute Cerebral Hemorrhage-2) trials. The exposure was hematoma volume, treated as a continuous measure in the primary analysis, and dichotomized by the median in the secondary analyses. The outcome was a symptomatic, clinically overt ischemic stroke, adjudicated centrally within each trial. We evaluated the association between hematoma volume and the risk of an ischemic stroke using Cox regression analyses after adjustment for demographics, vascular comorbidities, and ICH characteristics. RESULTS: Of 1470 patients with ICH, the mean age was 61.7 (SD, 12.8) years, and 574 (38.3%) were female. The median hematoma volume was 17.3 mL (interquartile range, 7.2-35.7). During a median follow-up of 107 days (interquartile range, 91-140), a total of 30 ischemic strokes occurred, of which 22 were in patients with a median ICH volume of ≥17.3 mL and a cumulative incidence of 4.6% (95% CI, 3.1-7.1). Among patients with a median ICH volume <17.3 mL, there were 8 ischemic strokes with a cumulative incidence of 3.1% (95% CI, 1.7-6.0). In primary analyses using adjusted Cox regression models, ICH volume was associated with an increased risk of ischemic stroke (hazard ratio, 1.02 per mL increase [95% CI, 1.01-1.04]). In secondary analyses, ICH volume of ≥17.3 mL was associated with an increased risk of ischemic stroke (hazard ratio, 2.5 [95% CI, 1.1-7.2]), compared with those with an ICH volume <17.3 mL. CONCLUSIONS: In a heterogeneous cohort of patients with ICH, initial hematoma volume was associated with a heightened short-term risk of ischemic stroke.


Asunto(s)
Accidente Cerebrovascular Isquémico , Accidente Cerebrovascular , Femenino , Humanos , Masculino , Persona de Mediana Edad , Antihipertensivos , Hemorragia Cerebral/diagnóstico por imagen , Hemorragia Cerebral/epidemiología , Hemorragia Cerebral/complicaciones , Hematoma/diagnóstico por imagen , Hematoma/epidemiología , Hematoma/complicaciones , Accidente Cerebrovascular Isquémico/complicaciones , Accidente Cerebrovascular/diagnóstico por imagen , Accidente Cerebrovascular/epidemiología , Accidente Cerebrovascular/etiología , Activador de Tejido Plasminógeno/uso terapéutico , Resultado del Tratamiento
6.
Stroke ; 55(1): 50-58, 2024 01.
Artículo en Inglés | MEDLINE | ID: mdl-38134264

RESUMEN

BACKGROUND: The effect of marine omega-3 PUFAs on risk of stroke remains unclear. METHODS: We investigated the associations between circulating and tissue omega-3 PUFA levels and incident stroke (total, ischemic, and hemorrhagic) in 29 international prospective cohorts. Each site conducted a de novo individual-level analysis using a prespecified analytical protocol with defined exposures, covariates, analytical methods, and outcomes; the harmonized data from the studies were then centrally pooled. Multivariable-adjusted HRs and 95% CIs across omega-3 PUFA quintiles were computed for each stroke outcome. RESULTS: Among 183 291 study participants, there were 10 561 total strokes, 8220 ischemic strokes, and 1142 hemorrhagic strokes recorded over a median of 14.3 years follow-up. For eicosapentaenoic acid, comparing quintile 5 (Q5, highest) with quintile 1 (Q1, lowest), total stroke incidence was 17% lower (HR, 0.83 [CI, 0.76-0.91]; P<0.0001), and ischemic stroke was 18% lower (HR, 0.82 [CI, 0.74-0.91]; P<0.0001). For docosahexaenoic acid, comparing Q5 with Q1, there was a 12% lower incidence of total stroke (HR, 0.88 [CI, 0.81-0.96]; P=0.0001) and a 14% lower incidence of ischemic stroke (HR, 0.86 [CI, 0.78-0.95]; P=0.0001). Neither eicosapentaenoic acid nor docosahexaenoic acid was associated with a risk for hemorrhagic stroke. These associations were not modified by either baseline history of AF or prevalent CVD. CONCLUSIONS: Higher omega-3 PUFA levels are associated with lower risks of total and ischemic stroke but have no association with hemorrhagic stroke.


Asunto(s)
Ácidos Grasos Omega-3 , Accidente Cerebrovascular Hemorrágico , Accidente Cerebrovascular Isquémico , Accidente Cerebrovascular , Humanos , Estudios Prospectivos , Ácido Eicosapentaenoico , Ácidos Docosahexaenoicos , Accidente Cerebrovascular Hemorrágico/epidemiología , Accidente Cerebrovascular/epidemiología , Factores de Riesgo
7.
Oncologist ; 29(3): 270-e413, 2024 Mar 04.
Artículo en Inglés | MEDLINE | ID: mdl-38325328

RESUMEN

BACKGROUND: Combination checkpoint inhibition therapy with yttrium-90 (Y90) radioembolization represents an emerging area of interest in the treatment of advanced hepatocellular carcinoma (HCC). HCRN GI15-225 is an open-label, single-arm multicenter, pilot study (NCT03099564). METHODS: Eligible patients had poor prognosis, localized HCC defined as having portal vein thrombus, multifocal disease, and/or diffuse disease that were not eligible for liver transplant or surgical resection. Patients received pembrolizumab 200 mg intravenously every 3 weeks in conjunction with glass yttrium-90 (Y90) radioembolization TheraSphere. Primary endpoint was 6-month progression-free survival (PFS6) per RECIST 1.1. Secondary endpoints included time to progression (TTP), objective response rate (ORR), overall survival (OS), and safety/tolerability. RESULTS: Between October 23, 2017 and November 24, 2020, 29 patients were enrolled: 2 were excluded per protocol. Fifteen of the remaining 27 patients were free of progression at 6 months (55.6%; 95% CI, 35.3-74.5) with median PFS 9.95 months (95% CI, 4.14-15.24) and OS 27.30 months (95% CI, 10.15-39.52). One patient was not evaluable for response due to death; among the remaining 26 patients, ORR was 30.8% (95% CI, 14.3-51.8) and DCR was 84.6% (95% CI, 65.1-95.6). CONCLUSION: In patients with localized, poor prognosis HCC, pembrolizumab in addition to glass Y90 radioembolization demonstrated promising efficacy and safety consistent with prior observations (ClinicalTrials.gov Identifier: NCT03099564; IRB Approved: 16-3255 approved July 12, 2016).


Asunto(s)
Anticuerpos Monoclonales Humanizados , Carcinoma Hepatocelular , Neoplasias Hepáticas , Radioisótopos de Itrio , Humanos , Carcinoma Hepatocelular/tratamiento farmacológico , Carcinoma Hepatocelular/radioterapia , Neoplasias Hepáticas/tratamiento farmacológico , Neoplasias Hepáticas/radioterapia , Proyectos Piloto , Supervivencia sin Progresión , Resultado del Tratamiento
8.
J Nutr ; 154(5): 1640-1651, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38141771

RESUMEN

BACKGROUND: Cognitive decline, and more specifically Alzheimer's disease, continues to increase in prevalence globally, with few, if any, adequate preventative approaches. Several tests of cognition are utilized in the diagnosis of cognitive decline that assess executive function, short- and long-term memory, cognitive flexibility, and speech and motor control. Recent studies have separately investigated the genetic component of both cognitive health, using these measures, and circulating fatty acids. OBJECTIVES: We aimed to examine the potential moderating effect of main species of ω-3 polyunsaturated fatty acids (PUFAs) on an individual's genetically conferred risk of cognitive decline. METHODS: The Offspring cohort from the Framingham Heart Study was cross-sectionally analyzed in this genome-wide interaction study (GWIS). Our sample included all individuals with red blood cell ω-3 PUFA, genetic, cognitive testing (via Trail Making Tests [TMTs]), and covariate data (N = 1620). We used linear mixed effects models to predict each of the 3 cognitive measures (TMT A, TMT B, and TMT D) by each ω-3 PUFA, single nucleotide polymorphism (SNP) (0, 1, or 2 minor alleles), ω-3 PUFA by SNP interaction term, and adjusting for sex, age, education, APOE ε4 genotype status, and kinship (relatedness). RESULTS: Our analysis identified 31 unique SNPs from 24 genes reaching an exploratory significance threshold of 1×10-5. Fourteen of the 24 genes have been previously associated with the brain/cognition, and 5 genes have been previously associated with circulating lipids. Importantly, 8 of the genes we identified, DAB1, SORCS2, SERINC5, OSBPL3, CPA6, DLG2, MUC19, and RGMA, have been associated with both cognition and circulating lipids. We identified 22 unique SNPs for which individuals with the minor alleles benefit substantially from increased ω-3 fatty acid concentrations and 9 unique SNPs for which the common homozygote benefits. CONCLUSIONS: In this GWIS of ω-3 PUFA species on cognitive outcomes, we identified 8 unique genes with plausible biology suggesting individuals with specific polymorphisms may have greater potential to benefit from increased ω-3 PUFA intake. Additional replication in prospective settings with more diverse samples is needed.


Asunto(s)
Eritrocitos , Ácidos Grasos Omega-3 , Estudio de Asociación del Genoma Completo , Memoria , Polimorfismo de Nucleótido Simple , Humanos , Ácidos Grasos Omega-3/sangre , Masculino , Femenino , Eritrocitos/metabolismo , Eritrocitos/química , Persona de Mediana Edad , Estudios Transversales , Estudios de Cohortes , Cognición , Anciano
9.
Cell ; 138(6): 1195-208, 2009 Sep 18.
Artículo en Inglés | MEDLINE | ID: mdl-19766571

RESUMEN

Progenitor cell nuclei in the rapidly expanding epithelium of the embryonic vertebrate central nervous system undergo a process called interkinetic nuclear migration (IKNM). Movements of IKNM are generally believed to involve smooth migration of nuclei from apical to basal and back during the G1 and G2 phases of the cell cycle, respectively. Yet, this has not been formally demonstrated, nor have the molecular mechanisms that drive IKNM been identified. Using time-lapse confocal microscopy to observe nuclear movements in zebrafish retinal neuroepithelial cells, we show that, except for brief apical nuclear translocations preceding mitosis, IKNM is stochastic rather than smooth and directed. We also show that IKNM is driven largely by actomyosin-dependent forces as it still occurs when the microtubule cytoskeleton is compromised but is blocked when MyosinII activity is inhibited.


Asunto(s)
Actomiosina/metabolismo , Núcleo Celular/metabolismo , Retina/citología , Pez Cebra/embriología , Animales , Complejo Dinactina , Embrión no Mamífero/citología , Embrión no Mamífero/metabolismo , Proteínas Asociadas a Microtúbulos/metabolismo , Células Neuroepiteliales/citología , Células Neuroepiteliales/metabolismo , Retina/embriología , Pez Cebra/metabolismo , Proteínas de Pez Cebra/metabolismo
10.
J Stroke Cerebrovasc Dis ; 33(1): 107472, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37944281

RESUMEN

BACKGROUND: While over half of US stroke patients were discharged to home, estimates of geographic access to outpatient stroke rehab facilities are unavailable. The objective of our study was to assess distance and travel time to the nearest outpatient stroke rehab facility in Tennessee, a high stroke prevalence state. METHODS: We systematically scraped Google Maps with the terms "stroke", "rehabilitation", and "outpatient" to identify Tennessee stroke rehab facilities. We then averaged/aggregated Census block-level travel distance and travel time to determine the mean travel distance/time to a facility for each of the 95 Tennessee counties and the overall state. Comparisons of mean travel time/distance were made between rural and urban counties and between low, medium, and high stroke prevalence counties. RESULTS: We found that 79% of facilities were in urban areas. Significantly higher median of mean travel times and distances (p values both <0.001) were observed in rural (22.0 miles, 31.6 min) versus urban counties (10.5 miles, 18.4 min). High (21.5 miles, 32.5 min) and medium (18.7 miles, 28.3 minutes) stroke prevalence counties, which often overlap with rural counties, had significantly higher median of mean travel times and distance than low stroke prevalence counties (7.3 miles, 14.5 min). CONCLUSIONS: Rural Tennessee counties were faced with high stroke prevalence, inadequate facilities, and significantly greater travel distance and time to access care. Additional efforts to address transportation barriers and accelerate telerehabilitation implementation are crucial for improving equal access to stroke aftercare in these areas.


Asunto(s)
Rehabilitación de Accidente Cerebrovascular , Accidente Cerebrovascular , Humanos , Tennessee/epidemiología , Accesibilidad a los Servicios de Salud , Pacientes Ambulatorios , Viaje , Accidente Cerebrovascular/diagnóstico , Accidente Cerebrovascular/epidemiología , Accidente Cerebrovascular/terapia , Población Rural
11.
Stroke ; 54(9): 2235-2240, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37534512

RESUMEN

BACKGROUND: The WASID trial (Warfarin-Aspirin Symptomatic Intracranial Disease) and the SAMMPRIS trial (Stenting and Aggressive Medical Management for Preventing Recurrent Stroke in Intracranial Stenosis) evaluated optimal management of symptomatic intracranial atherosclerotic stenosis. The aim of this retrospective, observational study was to determine whether aggressive medical management used in the SAMMPRIS trial ameliorated disparities in risk factor control between Black and non-Black patients. METHODS: The SAMMPRIS trial was a randomized controlled trial that enrolled patients with symptomatic intracranial atherosclerotic stenosis between November 2008 and April 2011. The frequency of risk factors at study entry (baseline) and mean levels of systolic blood pressure, diastolic blood pressure, LDL (low-density lipoprotein), hemoglobin A1c, and exercise level (quantified by physician-based assessment and counseling for exercise score) at baseline and at 1 year of follow-up were compared between Black (n=104) versus non-Black patients (n=347). RESULTS: Significant differences at baseline in Black patients (listed first) versus non-Black patients were age (57.5 versus 61.0 years; P=0.004), hypertension (95.2% versus 87.5%; P=0.027), diabetes (52.9% versus 39.7%; P=0.017), mean diastolic blood pressure (82.4 versus 79.5 mm Hg; P=0.035), and mean physician-based assessment and counseling for exercise score (2.7 versus 3.3; P=0.002). The mean diastolic blood pressure and mean physician-based assessment and counseling for exercise scores at 1 year in Black versus non-Black patients were 74.7 versus 75.5 mm Hg (P=0.575) and 4.2 versus 4.1 (P=0.593), respectively. No disparities in other modifiable risk factors emerged at 1 year. CONCLUSIONS: Significant differences in important risk factors (physical activity and diastolic blood pressure) at baseline between Black and non-Black patients resolved at 1 year, suggesting that aggressive medical management may have an important role in ameliorating disparities in risk factor control between Black and non-Black patients.


Asunto(s)
Arteriosclerosis Intracraneal , Accidente Cerebrovascular , Humanos , Persona de Mediana Edad , Accidente Cerebrovascular/etiología , Constricción Patológica/complicaciones , Estudios Retrospectivos , Factores de Riesgo , Arteriosclerosis Intracraneal/complicaciones , Stents/efectos adversos , Resultado del Tratamiento
12.
Plant Mol Biol ; 113(4-5): 237-247, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-38085407

RESUMEN

Modulation of the plant defense response by bioactive molecules is of increasing interest. However, despite plant cell lipids being one of the major cellular components, their role in plant immunity remains elusive. We found that the exogenous application of the cell-membrane localized phospholipid lyso-phosphatidylethanolamine (LPE) reprograms the plant transcript profile in favor of defense-associated genes thereby priming the plant immune system. Exogenous LPE application to different Arabidopsis accessions increases resistance against the necrotrophic pathogens, Botrytis cinerea and Cochliobolus heterostrophus. We found that the immunity-promoting effect of LPE is repealed in the jasmonic acid (JA) receptor mutant coi1, but multiplied in the JA-hypersensitive mutant feronia (fer-4). The JA-signaling repressor JAZ1 is degraded following LPE administration, suggesting that JA-signaling is promoted by LPE. Following LPE-treatment, reactive oxygen species (ROS) accumulation is affected in coi1 and fer-4. Moreover, FER signaling inhibitors of the RALF family are strongly expressed after LPE application, and RALF23 is internalized in stress granules, suggesting the LPE-mediated repression of FER-signaling by promoting RALF function. The in-situ increase of LPE-abundance in the LPE-catabolic mutants lpeat1 and lpeat2 elevates plant resistance to B. cinerea, in contrast to the endogenous LPE-deficient mutant pla2-alpha. We show that LPE increases plant resistance against necrotrophs by promoting JA-signaling and ROS-homeostasis, thereby paving the way for the LPE-targeted genomic engineering of crops to raise their ability to resist biotic threats.


Asunto(s)
Proteínas de Arabidopsis , Arabidopsis , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Fosfatidiletanolaminas/metabolismo , Fosfatidiletanolaminas/farmacología , Arabidopsis/metabolismo , Oxilipinas/metabolismo , Ciclopentanos/metabolismo , Homeostasis , Enfermedades de las Plantas/genética , Botrytis/metabolismo , Regulación de la Expresión Génica de las Plantas
13.
Am Heart J ; 262: 38-48, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37086938

RESUMEN

BACKGROUND: Tissue levels of n-3 polyunsaturated fatty acids (PUFAs) have been inversely related with risk of myocardial infarction (MI). Whether ratios of n-3 to n-6 PUFAs, reflecting both dietary intake of n-3 PUFAs and competing n-6 PUFAs, are better predictors of future MI than n-3 PUFA fractions is unclear. We aimed at investigating whether such ratios in adipose tissue better predict MI than n-3 PUFA fractions. METHODS: Subcutaneous adipose tissue biopsies were obtained in a random sample (n = 3,500) of the Diet, Cancer and Health cohort (n = 57,053). Adipose tissue content of eicosapentaenoic acid (EPA), docosapentaenoic acid (DPA), docosahexaenoic acid (DHA), alpha-linolenic acid (ALA), arachidonic acid (AA) and linoleic acid was determined using gas chromatography. Fractions of selected n-3 PUFAs and n-3/n-6 PUFA ratios were correlated to the 15-year occurrence of MI in a case-cohort design. RESULTS: A total of 2,406 participants experienced an MI during follow-up. Adipose tissue total marine n-3 PUFAs, EPA+DHA, EPA, EPA/AA, DHA/AA and (EPA + DPA + DHA)/AA were all inversely associated with risk of incident MI. Evaluating the predictive power (Harrel's C-index) of the selected metrics, fractions of marine n-3 PUFAs and ratios of EPA/AA, DHA/AA, (EPA + DHA)/AA and (EPA + DPA + DHA)/AA all refined risk prediction over age and sex alone. At multivariable analyses, however, the above ratios were the only metrics providing additional risk prediction. Differences in ratios were related to differences in food intake. CONCLUSIONS: Both adipose tissue n-3 PUFAs fractions and ratios of n-3 PUFAs/AA were associated with a lower occurrence of MI, but ratios provided superior risk prediction. Dietary strategies affecting n-3/n-6 PUFA ratios should be further investigated for prediction of MI with dietary interventions at the population level and in intervention studies.


Asunto(s)
Ácidos Grasos Omega-3 , Infarto del Miocardio , Humanos , Ácidos Grasos , Ácido Eicosapentaenoico , Ácidos Grasos Omega-6 , Ácido Araquidónico , Infarto del Miocardio/epidemiología , Tejido Adiposo
14.
Eur J Nucl Med Mol Imaging ; 50(4): 1051-1083, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36437425

RESUMEN

The blood-brain barrier (BBB) is the interface between the central nervous system and systemic circulation. It tightly regulates what enters and is removed from the brain parenchyma and is fundamental in maintaining brain homeostasis. Increasingly, the BBB is recognised as having a significant role in numerous neurological disorders, ranging from acute disorders (traumatic brain injury, stroke, seizures) to chronic neurodegeneration (Alzheimer's disease, vascular dementia, small vessel disease). Numerous approaches have been developed to study the BBB in vitro, in vivo, and ex vivo. The complex multicellular structure and effects of disease are difficult to recreate accurately in vitro, and functional aspects of the BBB cannot be easily studied ex vivo. As such, the value of in vivo methods to study the intact BBB cannot be overstated. This review discusses the structure and function of the BBB and how these are affected in diseases. It then discusses in depth several established and novel methods for imaging the BBB in vivo, with a focus on MRI, nuclear imaging, and high-resolution intravital fluorescence microscopy.


Asunto(s)
Enfermedad de Alzheimer , Accidente Cerebrovascular , Humanos , Barrera Hematoencefálica/diagnóstico por imagen , Encéfalo/irrigación sanguínea , Transporte Biológico
15.
Br J Nutr ; 130(2): 312-322, 2023 Jul 28.
Artículo en Inglés | MEDLINE | ID: mdl-36210531

RESUMEN

Information on the Omega-3 Index (O3I) in the United Kingdom (UK) is scarce. The UK-Biobank (UKBB) contains data on total plasma n3-PUFA% and DHA% measured by NMR. The aim of our study was to create an equation to estimate the O3I (eO3I) from these data. We first performed an inter-laboratory experiment with 250 random blood samples in which the O3I was measured in erythrocytes by GC, and total n3 % and DHA% were measured in plasma by NMR. The best predictor of eO3I included both DHA% and a derived metric, the total n3 %-DHA%. Together these explained 65 % of the variability (r = 0·832, P < 0·0001). We then estimated the O3I in 117 108 UKBB subjects and correlated it with demographic and lifestyle variables in multivariable-adjusted models. The mean eO3I was 5·58 % (sd 2·35 %) in this UKBB cohort. Several predictors were significantly correlated with eO3I (all P < 0·0001). In general order of impact and with directionality (-, inverse and +, direct): oily-fish consumption (+), fish oil supplement use (+), female sex (+), older age (+), alcohol use (+), smoking (-), higher waist circumference and BMI (-), lower socioeconomic status and less education (-). Only 20·5 % of eO3I variability could be explained by predictors investigated, and oily fish consumption accounted for 7·0 % of that. With the availability of the eO3I in the UKBB cohort, we will be in a position to link risk for a variety of diseases with this commonly used and well-documented marker of n3-PUFA biostatus.


Asunto(s)
Ácido Eicosapentaenoico , Ácidos Grasos Omega-3 , Femenino , Animales , Ácidos Docosahexaenoicos , Bancos de Muestras Biológicas , Suplementos Dietéticos , Reino Unido
16.
Annu Rev Cell Dev Biol ; 25: 45-69, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-19575661

RESUMEN

Multipotent retinal progenitors undergo a varied number of divisions to produce clones of heterogeneous sizes and cell types. We describe the transition from a proliferating progenitor to a differentiated postmitotic cell and discuss how controls of proliferation operate within individual cells as well as in the whole tissue. We discuss how extracellular and intracellular signaling, transcriptional regulation, cell cycle kinetics, interkinetic nuclear migration, orientation of cell division, and epigenetic modifications all interact to regulate a progenitor's transition from division to differentiation. We also propose some directions for future research.


Asunto(s)
Diferenciación Celular , Retina/citología , Células Madre/citología , Animales , Humanos , Retina/metabolismo , Células Madre/metabolismo
17.
Br J Nurs ; 32(8): 372-377, 2023 Apr 20.
Artículo en Inglés | MEDLINE | ID: mdl-37083380

RESUMEN

Clinical coding, the method by which departments are reimbursed for providing services to patients, is widely mispractised within the NHS. Improving clinical coding accuracy therefore offers an opportunity to increase departmental income, guide efficient resource allocation and enable staff development. The authors audited the clinical coding in outpatient hysteroscopy clinics at their institution and found that coding errors were both prevalent and correctable. By implementing simple changes in coding procedure, and without any additional administrative cost, they significantly improved coding accuracy and achieved an increase in total annual tariffs. Although not applicable in a block contract, this will become highly relevant in a restoration of the Payment by Results tariff system. Nurse development is a key objective of the NHS Long Term Plan but can be hindered by staff costs, which require departmental funding. In the authors' institution, improved clinical coding accuracy directly led to a departmental restructuring, funded the development of a new hysteroscopy nurse development and improved care delivery. Coding errors are not unique to the authors' trust, yet simple amendments led to meaningful changes. Therefore, careful auditing and implemented change are needed to raise national clinical coding standards, to enable clinical restructuring, staff development, and provide more efficient, patient-centred care.


Asunto(s)
Histeroscopía , Enfermeras Clínicas , Femenino , Embarazo , Humanos , Atención a la Salud
18.
Oncologist ; 27(12): 1025-1033, 2022 12 09.
Artículo en Inglés | MEDLINE | ID: mdl-36124727

RESUMEN

BACKGROUND: KRAS variant alleles may have differential biological properties which impact prognosis and therapeutic options in pancreatic ductal adenocarcinomas (PDA). MATERIALS AND METHODS: We retrospectively identified patients with advanced PDA who received first-line therapy and underwent blood and/or tumor genomic sequencing at the University of Washington between 2013 and 2020. We examined the incidence of KRAS mutation variants with and without co-occurring PI3K or other genomic alterations and evaluated the association of these mutations with clinicopathological characteristics and survival using a Cox proportional hazards model. RESULTS: One hundred twenty-six patients had genomic sequencing data; KRAS mutations were identified in 111 PDA and included the following variants: G12D (43)/G12V (35)/G12R (23)/other (10). PI3K pathway mutations (26% vs. 8%) and homologous recombination DNA repair (HRR) defects (35% vs. 12.5%) were more common among KRAS G12R vs. non-G12R mutated cancers. Patients with KRAS G12R vs. non-G12R cancers had significantly longer overall survival (OS) (HR 0.55) and progression-free survival (PFS) (HR 0.58), adjusted for HRR pathway co-mutations among other covariates. Within the KRAS G12R group, co-occurring PI3K pathway mutations were associated with numerically shorter OS (HR 1.58), while no effect was observed on PFS. CONCLUSIONS: Patients with PDA harboring KRAS G12R vs. non-G12R mutations have longer survival, but this advantage was offset by co-occurring PI3K alterations. The KRAS/PI3K genomic profile could inform therapeutic vulnerabilities in patients with PDA.


Asunto(s)
Neoplasias , Fosfatidilinositol 3-Quinasas , Humanos , Fosfatidilinositol 3-Quinasas/genética , Estudios Retrospectivos , Genómica , Mutación , Proteínas Proto-Oncogénicas p21(ras)/genética
19.
Curr Oncol Rep ; 24(7): 917-927, 2022 07.
Artículo en Inglés | MEDLINE | ID: mdl-35347594

RESUMEN

PURPOSE OF REVIEW: The systemic treatment of advanced hepatocellular carcinoma (HCC) has significantly evolved. Immune checkpoint inhibitors (ICIs) have demonstrated clinical efficacy and more favorable toxicity profiles compared to multikinase inhibitors. Combination therapy with ICIs may provide greater anti-tumor activity compared to ICI monotherapy. This review will discuss the current treatment landscape of advanced HCC, with a focus on recently completed and ongoing trials of ICI combinations, as well as future directions.  RECENT FINDINGS: Atezolizumab/bevacizumab has been approved as first-line therapy in patients with advanced HCC based on its superiority over sorafenib in the pivotal IMbrave150 trial. Similarly, durvalumab/tremelimumab demonstrated an improvement in overall survival compared to sorafenib in the HIMALAYA trial. Other combinations of ICIs with targeted agents and dual immune checkpoint blockade are currently being investigated in large randomized Phase 3 trials for the first-line treatment of HCC. Results of several ICI combination trials have been reported or are anticipated in the next few years and may potentially expand the therapy options in this patient population. Further areas of exploration include the use of ICIs in earlier stages of disease, other immunotherapy approaches such as adoptive T cell therapy, and the identification of predictive biomarkers. These ongoing efforts will likely further improve patient outcomes in the future.


Asunto(s)
Carcinoma Hepatocelular , Neoplasias Hepáticas , Carcinoma Hepatocelular/tratamiento farmacológico , Carcinoma Hepatocelular/patología , Humanos , Inhibidores de Puntos de Control Inmunológico/uso terapéutico , Inmunoterapia , Neoplasias Hepáticas/tratamiento farmacológico , Neoplasias Hepáticas/patología , Sorafenib/uso terapéutico
20.
Eur J Nutr ; 61(3): 1585-1594, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-34988653

RESUMEN

PURPOSE: To evaluate the relationship between red blood cell (RBC) polyunsaturated fatty acid (PUFA) levels, and dietary PUFA and fish intake, with prevalent and incident age-related macular degeneration (AMD) in a US cohort of postmenopausal women. METHODS: This analysis included 1456 postmenopausal women from the Women's Health Initiative (WHI) Clinical Trials. RBC PUFAs were measured from fasting serum samples collected at WHI baseline. Dietary PUFAs and fish intake were assessed via food frequency questionnaires at baseline. There were 240 women who had prevalent AMD and 138 who self-reported AMD development over 9.5 years. Adjusted odds ratios and 95% confidence intervals were estimated for prevalent AMD by RBC PUFA levels, dietary PUFA intake, and frequency of fish consumption. Adjusted hazard ratios and 95% confidence intervals were estimated for incident AMD. A p-for-trend was estimated for continuous measures of dietary PUFA and fish intake. RESULTS: No significant association was found between prevalent or incident AMD and RBC docosahexaenoic acid (DHA) + eicosapentaenoic acid (EPA), EPA, DHA, alpha-linolenic acid (ALA), linoleic acid (LA), or arachidonic acid (AA). A positive association was found between dietary intake of AA and odds of prevalent AMD (p-for-trend for continuous AA intake = 0.02) and between intake of LA/ALA and incident AMD (p-for-trend for continuous ratio of LA/ALA intake = 0.03). No statistically significant associations were found between AMD and dietary intake of PUFAs or fish. CONCLUSIONS: RBC PUFAs were not associated with AMD in this cohort. Overall, dietary analyses of PUFAs supported this, excepting dietary AA intake and intake of LA in proportion to ALA of which there were trends of increased risk.


Asunto(s)
Ácidos Grasos Omega-3 , Degeneración Macular , Animales , Ácido Eicosapentaenoico , Eritrocitos , Ácidos Grasos , Femenino , Degeneración Macular/epidemiología , Posmenopausia
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