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1.
Nat Immunol ; 23(1): 40-49, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-34937928

RESUMEN

SARS-CoV-2 infection is generally mild or asymptomatic in children but a biological basis for this outcome is unclear. Here we compare antibody and cellular immunity in children (aged 3-11 years) and adults. Antibody responses against spike protein were high in children and seroconversion boosted responses against seasonal Beta-coronaviruses through cross-recognition of the S2 domain. Neutralization of viral variants was comparable between children and adults. Spike-specific T cell responses were more than twice as high in children and were also detected in many seronegative children, indicating pre-existing cross-reactive responses to seasonal coronaviruses. Importantly, children retained antibody and cellular responses 6 months after infection, whereas relative waning occurred in adults. Spike-specific responses were also broadly stable beyond 12 months. Therefore, children generate robust, cross-reactive and sustained immune responses to SARS-CoV-2 with focused specificity for the spike protein. These findings provide insight into the relative clinical protection that occurs in most children and might help to guide the design of pediatric vaccination regimens.


Asunto(s)
Anticuerpos Antivirales/inmunología , Coronavirus Humano 229E/inmunología , Coronavirus Humano OC43/inmunología , Protección Cruzada/inmunología , SARS-CoV-2/inmunología , Glicoproteína de la Espiga del Coronavirus/inmunología , Inmunidad Adaptativa/inmunología , Adulto , Anticuerpos Neutralizantes/inmunología , COVID-19/inmunología , Vacunas contra la COVID-19/inmunología , Niño , Preescolar , Reacciones Cruzadas/inmunología , Humanos
2.
Mol Cell ; 84(4): 640-658.e10, 2024 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-38266639

RESUMEN

The Bloom syndrome helicase BLM interacts with topoisomerase IIIα (TOP3A), RMI1, and RMI2 to form the BTR complex, which dissolves double Holliday junctions and DNA replication intermediates to promote sister chromatid disjunction before cell division. In its absence, structure-specific nucleases like the SMX complex (comprising SLX1-SLX4, MUS81-EME1, and XPF-ERCC1) can cleave joint DNA molecules instead, but cells deficient in both BTR and SMX are not viable. Here, we identify a negative genetic interaction between BLM loss and deficiency in the BRCA1-BARD1 tumor suppressor complex. We show that this is due to a previously overlooked role for BARD1 in recruiting SLX4 to resolve DNA intermediates left unprocessed by BLM in the preceding interphase. Consequently, cells with defective BLM and BRCA1-BARD1 accumulate catastrophic levels of chromosome breakage and micronucleation, leading to cell death. Thus, we reveal mechanistic insights into SLX4 recruitment to DNA lesions, with potential clinical implications for treating BRCA1-deficient tumors.


Asunto(s)
Proteínas de Unión al ADN , Recombinasas , Humanos , ADN/genética , Reparación del ADN , Replicación del ADN , ADN Cruciforme , Proteínas de Unión al ADN/genética , Proteínas de Unión al ADN/metabolismo , Recombinasas/genética , RecQ Helicasas/genética , RecQ Helicasas/metabolismo
3.
Mol Cell ; 82(18): 3382-3397.e7, 2022 09 15.
Artículo en Inglés | MEDLINE | ID: mdl-36002001

RESUMEN

Aberrant replication causes cells lacking BRCA2 to enter mitosis with under-replicated DNA, which activates a repair mechanism known as mitotic DNA synthesis (MiDAS). Here, we identify genome-wide the sites where MiDAS reactions occur when BRCA2 is abrogated. High-resolution profiling revealed that these sites are different from MiDAS at aphidicolin-induced common fragile sites in that they map to genomic regions replicating in the early S-phase, which are close to early-firing replication origins, are highly transcribed, and display R-loop-forming potential. Both transcription inhibition in early S-phase and RNaseH1 overexpression reduced MiDAS in BRCA2-deficient cells, indicating that transcription-replication conflicts (TRCs) and R-loops are the source of MiDAS. Importantly, the MiDAS sites identified in BRCA2-deficient cells also represent hotspots for genomic rearrangements in BRCA2-mutated breast tumors. Thus, our work provides a mechanism for how tumor-predisposing BRCA2 inactivation links transcription-induced DNA damage with mitotic DNA repair to fuel the genomic instability characteristic of cancer cells.


Asunto(s)
Replicación del ADN , Mitosis , Afidicolina/farmacología , Proteína BRCA2/genética , Sitios Frágiles del Cromosoma/genética , ADN/genética , Daño del ADN , Inestabilidad Genómica , Humanos , Mitosis/genética
4.
PLoS Biol ; 22(2): e3002494, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38319934

RESUMEN

Effective interactions with the environment rely on the integration of multisensory signals: Our brains must efficiently combine signals that share a common source, and segregate those that do not. Healthy ageing can change or impair this process. This functional magnetic resonance imaging study assessed the neural mechanisms underlying age differences in the integration of auditory and visual spatial cues. Participants were presented with synchronous audiovisual signals at various degrees of spatial disparity and indicated their perceived sound location. Behaviourally, older adults were able to maintain localisation accuracy. At the neural level, they integrated auditory and visual cues into spatial representations along dorsal auditory and visual processing pathways similarly to their younger counterparts but showed greater activations in a widespread system of frontal, temporal, and parietal areas. According to multivariate Bayesian decoding, these areas encoded critical stimulus information beyond that which was encoded in the brain areas commonly activated by both groups. Surprisingly, however, the boost in information provided by these areas with age-related activation increases was comparable across the 2 age groups. This dissociation-between comparable information encoded in brain activation patterns across the 2 age groups, but age-related increases in regional blood-oxygen-level-dependent responses-contradicts the widespread notion that older adults recruit new regions as a compensatory mechanism to encode task-relevant information. Instead, our findings suggest that activation increases in older adults reflect nonspecific or modulatory mechanisms related to less efficient or slower processing, or greater demands on attentional resources.


Asunto(s)
Mapeo Encefálico , Percepción Visual , Humanos , Anciano , Teorema de Bayes , Percepción Visual/fisiología , Encéfalo/fisiología , Atención/fisiología , Estimulación Acústica/métodos , Percepción Auditiva/fisiología , Estimulación Luminosa/métodos , Imagen por Resonancia Magnética
5.
Mol Cell ; 74(3): 571-583.e8, 2019 05 02.
Artículo en Inglés | MEDLINE | ID: mdl-30898438

RESUMEN

In mitosis, cells inactivate DNA double-strand break (DSB) repair pathways to preserve genome stability. However, some early signaling events still occur, such as recruitment of the scaffold protein MDC1 to phosphorylated histone H2AX at DSBs. Yet, it remains unclear whether these events are important for maintaining genome stability during mitosis. Here, we identify a highly conserved protein-interaction surface in MDC1 that is phosphorylated by CK2 and recognized by the DNA-damage response mediator protein TOPBP1. Disruption of MDC1-TOPBP1 binding causes a specific loss of TOPBP1 recruitment to DSBs in mitotic but not interphase cells, accompanied by mitotic radiosensitivity, increased micronuclei, and chromosomal instability. Mechanistically, we find that TOPBP1 forms filamentous structures capable of bridging MDC1 foci in mitosis, indicating that MDC1-TOPBP1 complexes tether DSBs until repair is reactivated in the following G1 phase. Thus, we reveal an important, hitherto-unnoticed cooperation between MDC1 and TOPBP1 in maintaining genome stability during cell division.


Asunto(s)
Proteínas Portadoras/genética , Inestabilidad Cromosómica/genética , Proteínas de Unión al ADN/genética , Mitosis/genética , Proteínas Nucleares/genética , Transactivadores/genética , Proteínas Adaptadoras Transductoras de Señales , Proteínas de Ciclo Celular , Roturas del ADN de Doble Cadena , Daño del ADN/genética , Reparación del ADN/genética , Fase G1/genética , Genoma Humano/genética , Inestabilidad Genómica/genética , Histonas , Humanos , Fosforilación , Transducción de Señal/genética
6.
Hum Mol Genet ; 32(1): 161-171, 2023 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-36018815

RESUMEN

Tuberculosis is a significant public health concern resulting in the death of over 1 million individuals each year worldwide. While treatment options and vaccines exist, a substantial number of infections still remain untreated or are caused by treatment resistant strains. Therefore, it is important to identify mechanisms that contribute to risk and prognosis of tuberculosis as this may provide tools to understand disease mechanisms and provide novel treatment options for those with severe infection. Our goal was to identify genetic risk factors that contribute to the risk of tuberculosis and to understand biological mechanisms and causality behind the risk of tuberculosis. A total of 1895 individuals in the FinnGen study had International Classification of Diseases-based tuberculosis diagnosis. Genome-wide association study analysis identified genetic variants with statistically significant association with tuberculosis at the human leukocyte antigen (HLA) region (P < 5e-8). Fine mapping of the HLA association provided evidence for one protective haplotype tagged by HLA DQB1*05:01 (P = 1.82E-06, OR = 0.81 [CI 95% 0.74-0.88]), and predisposing alleles tagged by HLA DRB1*13:02 (P = 0.00011, OR = 1.35 [CI 95% 1.16-1.57]). Furthermore, genetic correlation analysis showed association with earlier reported risk factors including smoking (P < 0.05). Mendelian randomization supported smoking as a risk factor for tuberculosis (inverse-variance weighted P < 0.05, OR = 1.83 [CI 95% 1.15-2.93]) with no significant evidence of pleiotropy. Our findings indicate that specific HLA alleles associate with the risk of tuberculosis. In addition, lifestyle risk factors such as smoking contribute to the risk of developing tuberculosis.


Asunto(s)
Predisposición Genética a la Enfermedad , Tuberculosis , Humanos , Estudio de Asociación del Genoma Completo , Tuberculosis/genética , Cadenas beta de HLA-DQ/genética , Cadenas HLA-DRB1/genética , Haplotipos/genética , Factores de Riesgo , Alelos , Frecuencia de los Genes
7.
Proc Natl Acad Sci U S A ; 119(6)2022 02 08.
Artículo en Inglés | MEDLINE | ID: mdl-35115399

RESUMEN

The RecQ-like helicase BLM cooperates with topoisomerase IIIα, RMI1, and RMI2 in a heterotetrameric complex (the "Bloom syndrome complex") for dissolution of double Holliday junctions, key intermediates in homologous recombination. Mutations in any component of the Bloom syndrome complex can cause genome instability and a highly cancer-prone disorder called Bloom syndrome. Some heterozygous carriers are also predisposed to breast cancer. To understand how the activities of BLM helicase and topoisomerase IIIα are coupled, we purified the active four-subunit complex. Chemical cross-linking and mass spectrometry revealed a unique architecture that links the helicase and topoisomerase domains. Using biochemical experiments, we demonstrated dimerization mediated by the N terminus of BLM with a 2:2:2:2 stoichiometry within the Bloom syndrome complex. We identified mutations that independently abrogate dimerization or association of BLM with RMI1, and we show that both are dysfunctional for dissolution using in vitro assays and cause genome instability and synthetic lethal interactions with GEN1/MUS81 in cells. Truncated BLM can also inhibit the activity of full-length BLM in mixed dimers, suggesting a putative mechanism of dominant-negative action in carriers of BLM truncation alleles. Our results identify critical molecular determinants of Bloom syndrome complex assembly required for double Holliday junction dissolution and maintenance of genome stability.


Asunto(s)
Síndrome de Bloom/genética , ADN Cruciforme/genética , Inestabilidad Genómica/genética , Alelos , Proteínas Portadoras/genética , Línea Celular , ADN-Topoisomerasas de Tipo I/genética , Humanos , Mutación/genética , Unión Proteica/genética , RecQ Helicasas/genética , Recombinación Genética/genética , Solubilidad
8.
PLoS Genet ; 18(9): e1010356, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-36137075

RESUMEN

Rare variants in ten genes have been reported to cause Mendelian sleep conditions characterised by extreme sleep duration or timing. These include familial natural short sleep (ADRB1, DEC2/BHLHE41, GRM1 and NPSR1), advanced sleep phase (PER2, PER3, CRY2, CSNK1D and TIMELESS) and delayed sleep phase (CRY1). The association of variants in these genes with extreme sleep conditions were usually based on clinically ascertained families, and their effects when identified in the population are unknown. We aimed to determine the effects of these variants on sleep traits in large population-based cohorts. We performed genetic association analysis of variants previously reported to be causal for Mendelian sleep and circadian conditions. Analyses were performed using 191,929 individuals with data on sleep and whole-exome or genome-sequence data from 4 population-based studies: UK Biobank, FINRISK, Health-2000-2001, and the Multi-Ethnic Study of Atherosclerosis (MESA). We identified sleep disorders from self-report, hospital and primary care data. We estimated sleep duration and timing measures from self-report and accelerometery data. We identified carriers for 10 out of 12 previously reported pathogenic variants for 8 of the 10 genes. They ranged in frequency from 1 individual with the variant in CSNK1D to 1,574 individuals with a reported variant in the PER3 gene in the UK Biobank. No carriers for variants reported in NPSR1 or PER2 were identified. We found no association between variants analyzed and extreme sleep or circadian phenotypes. Using sleep timing as a proxy measure for sleep phase, only PER3 and CRY1 variants demonstrated association with earlier and later sleep timing, respectively; however, the magnitude of effect was smaller than previously reported (sleep midpoint ~7 mins earlier and ~5 mins later, respectively). We also performed burden tests of protein truncating (PTVs) or rare missense variants for the 10 genes. Only PTVs in PER2 and PER3 were associated with a relevant trait (for example, 64 individuals with a PTV in PER2 had an odds ratio of 4.4 for being "definitely a morning person", P = 4x10-8; and had a 57-minute earlier midpoint sleep, P = 5x10-7). Our results indicate that previously reported variants for Mendelian sleep and circadian conditions are often not highly penetrant when ascertained incidentally from the general population.


Asunto(s)
Ritmo Circadiano , Trastornos del Sueño-Vigilia , Ritmo Circadiano/genética , Humanos , Fenotipo , Receptores Acoplados a Proteínas G/genética , Sueño/genética , Trastornos del Sueño-Vigilia/genética
9.
J Biol Chem ; 299(3): 102967, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36736429

RESUMEN

High-resolution structures of voltage-gated sodium channels (Nav) were first obtained from a prokaryotic ortholog NavAb, which provided important mechanistic insights into Na+ selectivity and voltage gating. Unlike eukaryotic Navs, the NavAb channel is formed by four identical subunits, but its ion selectivity and pharmacological profiles are very similar to eukaryotic Navs. Recently, the structures of the NavAb voltage sensor at resting and activated states were obtained by cryo-EM, but its intermediate states and transition dynamics remain unclear. In the present work, we used liposome flux assays to show that purified NavAb proteins were functional to conduct both H+ and Na+ and were blocked by the local anesthetic lidocaine. Additionally, we examined the real-time conformational dynamics of the NavAb voltage sensor using single-molecule FRET. Our single-molecule FRET measurements on the tandem NavAb channel labeled with Cy3/5 FRET fluorophore pair revealed spontaneous transitions of the NavAb S4 segment among three conformational states, which fitted well with the kinetic model developed for the S4 segment of the human voltage-gated proton channel hHv1. Interestingly, even under strong activating voltage, the NavAb S4 segment seems to adopt a conformational distribution similar to that of the hHv1 S4 segment at a deep resting state. The conformational behaviors of the NavAb voltage sensor under different voltages need to be further examined to understand the mechanisms of voltage sensing and gating in the canonical voltage-gated ion channel superfamily.


Asunto(s)
Proteínas Bacterianas , Activación del Canal Iónico , Canales de Sodio Activados por Voltaje , Conformación Proteica , Canales de Sodio Activados por Voltaje/metabolismo , Bacterias , Proteínas Bacterianas/metabolismo
10.
J Biol Chem ; 299(7): 104918, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-37315791

RESUMEN

Unlike other members of the voltage-gated ion channel superfamily, voltage-gated proton (Hv) channels are solely composed of voltage sensor domains without separate ion-conducting pores. Due to their unique dependence on both voltage and transmembrane pH gradients, Hv channels normally open to mediate proton efflux. Multiple cellular ligands were also found to regulate the function of Hv channels, including Zn2+, cholesterol, polyunsaturated arachidonic acid, and albumin. Our previous work showed that Zn2+ and cholesterol inhibit the human voltage-gated proton channel (hHv1) by stabilizing its S4 segment at resting state conformations. Released from phospholipids by phospholipase A2 in cells upon infection or injury, arachidonic acid regulates the function of many ion channels, including hHv1. In the present work, we examined the effects of arachidonic acid on purified hHv1 channels using liposome flux assays and revealed underlying structural mechanisms using single-molecule FRET. Our data indicated that arachidonic acid strongly activates hHv1 channels by promoting transitions of the S4 segment toward opening or "preopening" conformations. Moreover, we found that arachidonic acid even activates hHv1 channels inhibited by Zn2+ and cholesterol, providing a biophysical mechanism to activate hHv1 channels in nonexcitable cells upon infection or injury.


Asunto(s)
Ácido Araquidónico , Colesterol , Activación del Canal Iónico , Canales Iónicos , Protones , Zinc , Humanos , Albúminas/farmacología , Ácido Araquidónico/farmacología , Colesterol/farmacología , Transferencia Resonante de Energía de Fluorescencia , Activación del Canal Iónico/efectos de los fármacos , Canales Iónicos/agonistas , Canales Iónicos/antagonistas & inhibidores , Canales Iónicos/química , Canales Iónicos/metabolismo , Liposomas/metabolismo , Fosfolipasas A2/metabolismo , Imagen Individual de Molécula , Zinc/farmacología , Concentración de Iones de Hidrógeno
11.
BMC Genomics ; 25(1): 256, 2024 Mar 07.
Artículo en Inglés | MEDLINE | ID: mdl-38454350

RESUMEN

BACKGROUND: Congenital heart defects (CHD) are structural defects of the heart affecting approximately 1% of newborns. They exhibit low penetrance and non-Mendelian patterns of inheritance as varied and complex traits. While genetic factors are known to play an important role in the development of CHD, the specific genetics remain unknown for the majority of patients. To elucidate the underlying genetic risk, we performed a genome wide association study (GWAS) of CHDs in general and specific CHD subgroups using the FinnGen Release 10 (R10) (N > 393,000), followed by functional fine-mapping through eQTL and co-localization analyses using the GTEx database. RESULTS: We discovered three genome-wide significant loci associated with general CHD. Two of them were located in chromosome 17: 17q21.32 (rs2316327, intronic: LRRC37A2, Odds ratio (OR) [95% Confidence Interval (CI)] = 1.17[1.12-1.23], p = 1.5 × 10-9) and 17q25.3 (rs1293973611, nearest: BAHCC1, OR[95%CI] = 4.48[2.80-7.17], p = 7.0 × 10-10), respectively, and in addition to general CHD, the rs1293973611 locus was associated with the septal defect subtype. The third locus was in band 1p21.2 (rs35046143, nearest: PALMD, OR[95%CI] = 1.15[1.09-1.21], p = 7.1 × 10-9), and it was associated with general CHD and left-sided lesions. In the subgroup analysis, two additional loci were associated with septal defects (rs75230966 and rs6824295), and one with left-sided lesions (rs1305393195). In the eQTL analysis the variants rs2316327 (general CHD), and rs75230966 (septal defects) both located in 17q21.32 (with a LD r2 of 0.41) were both predicted to significantly associate with the expression of WNT9B in the atrial appendage tissue category. This effect was further confirmed by co-localization analysis, which also implicated WNT3 expression in the atrial appendage. A meta-analysis of general CHD together with the UK Biobank (combined N = 881,678) provided a different genome-wide significant locus in LRRC37A2; rs16941382 (OR[95%CI] = 1.15[1.11-1.20], p = 1.5 × 10-9) which is in significant LD with rs2316327. CONCLUSIONS: Our results of general CHD and different CHD subcategories identified a complex risk locus on chromosome 17 near BAHCC1 and LRRC37A2, interacting with the genes WNT9B, WNT3 and MYL4, may constitute potential novel CHD risk associated loci, warranting future experimental tests to determine their role.


Asunto(s)
Estudio de Asociación del Genoma Completo , Cardiopatías Congénitas , Humanos , Recién Nacido , Predisposición Genética a la Enfermedad , Cardiopatías Congénitas/genética , Factores de Riesgo , Bases de Datos Genéticas
12.
Biomacromolecules ; 25(3): 1629-1636, 2024 Mar 11.
Artículo en Inglés | MEDLINE | ID: mdl-38361251

RESUMEN

There is a high demand for rapid, sensitive, and accurate detection methods for pathogens. This paper demonstrates a method of detecting the presence of amplified DNA from a range of pathogens associated with serious infections including Gram-negative bacteria, Gram-positive bacteria, and viruses. DNA is amplified using a polymerase chain reaction (PCR) and consequently detected using a sterically stabilized, cationic polymer latex. The DNA induces flocculation of this cationic latex, which consequently leads to rapid sedimentation and a visible change from a milky-white dispersion to one with a transparent supernatant, presenting a clear visible change, indicating the presence of amplified DNA. Specifically, a number of different pathogens were amplified using conventional or qPCR, including Staphylococcus aureus, Escherichia coli, and Herpes Simplex Virus (HSV-2). This method was demonstrated to detect the presence of bacteria in suspension concentrations greater than 380 CFU mL-1 and diagnose the presence of specific genomes through primer selection, as exemplified using methicillin resistant and methicillin susceptible Staphylococcus aureus. The versatility of this methodology was further demonstrated by showing that false positive results do not occur when a PCR of fungal DNA from C. albicans is conducted using bacterial universal primers.


Asunto(s)
Técnicas Biosensibles , Látex , Floculación , ADN/genética , Staphylococcus aureus/genética , Reacción en Cadena de la Polimerasa/métodos , ADN Bacteriano/genética , Sensibilidad y Especificidad
13.
Dev Sci ; 27(4): e13492, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38553823

RESUMEN

This paper presents rational inattention as a new, transdiagnostic theory of information seeking in neurodevelopmental conditions that have uneven cognitive and socio-emotional profiles, including developmental language disorder (DLD), dyslexia, dyscalculia and autism. Rational inattention holds that the optimal solution to minimizing epistemic uncertainty is to avoid imprecise information sources. The key theoretical contribution of this report is to endogenize imprecision, making it a function of the primary neurocognitive difficulties that have been invoked to explain neurodivergent phenotypes, including deficits in auditory perception, working memory, procedural learning and the social brain network. We argue that disengagement with information sources with low endogenous precision (e.g. speech in DLD, orthography-phonology mappings in dyslexia, numeric stimuli in dyscalculia and social signals in autism) constitutes resource-rational behaviour. We demonstrate the strength of this account in a series of computational simulations. In experiment 1, we simulate information seeking in artificial agents mimicking an array of neurodivergent phenotypes, which optimally explore a complex learning environment containing speech, text, numeric stimuli and social cues. In experiment 2, we simulate optimal information seeking in a cross-modal dual-task paradigm and qualitatively replicate empirical data from children with and without DLD. Across experiments, simulated agents' only aim was to maximally reduce epistemic uncertainty, with no difference in reward across information sources. We show that rational inattention emerges naturally in specific neurodivergent phenotypes as a function of low endogenous precision. For instance, an agent mimicking the DLD phenotype disengages with speech (and preferentially engages with alternative precise information sources) because endogenous imprecision renders speech not conducive to information gain. Because engagement is necessary for learning, simulation demonstrates how optimal information seeking may paradoxically contribute negatively to an already delayed learning trajectory in neurodivergent children. RESEARCH HIGHLIGHTS: We present the first comprehensive theory of information seeking in neurodivergent children to date, centred on the notion of rational inattention. We demonstrate the strength of this account in a series of computational simulations involving artificial agents mimicking specific neurodivergent phenotypes that optimally explore a complex learning environment containing speech, text, numeric stimuli, and social cues. We show how optimal information seeking may, paradoxically, contribute negatively to an already delayed learning trajectory in neurodivergent children. This report advances our understanding of the factors shaping short-term decision making and long-term learning in neurodivergent children.


Asunto(s)
Atención , Humanos , Atención/fisiología , Conducta en la Búsqueda de Información/fisiología , Aprendizaje/fisiología , Trastornos del Desarrollo del Lenguaje/fisiopatología , Simulación por Computador , Cognición/fisiología
14.
Adv Exp Med Biol ; 1437: 59-76, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38270853

RESUMEN

Multisensory perception is critical for effective interaction with the environment, but human responses to multisensory stimuli vary across the lifespan and appear changed in some atypical populations. In this review chapter, we consider multisensory integration within a normative Bayesian framework. We begin by outlining the complex computational challenges of multisensory causal inference and reliability-weighted cue integration, and discuss whether healthy young adults behave in accordance with normative Bayesian models. We then compare their behaviour with various other human populations (children, older adults, and those with neurological or neuropsychiatric disorders). In particular, we consider whether the differences seen in these groups are due only to changes in their computational parameters (such as sensory noise or perceptual priors), or whether the fundamental computational principles (such as reliability weighting) underlying multisensory perception may also be altered. We conclude by arguing that future research should aim explicitly to differentiate between these possibilities.


Asunto(s)
Estado de Salud , Longevidad , Niño , Adulto Joven , Humanos , Anciano , Teorema de Bayes , Reproducibilidad de los Resultados , Causalidad
15.
J Sleep Res ; : e13973, 2023 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-37380357

RESUMEN

Little is known regarding the shared genetic influences underlying the observed phenotypic association between chronotype and breast cancer in women. Leveraging summary statistics from the hitherto largest genome-wide association study conducted in each trait, we investigated the genetic correlation, pleiotropic loci, and causal relationship of chronotype with overall breast cancer, and with its subtypes defined by the status of oestrogen receptor. We identified a negative genomic correlation between chronotype and overall breast cancer ( r g $$ {r}_g $$ = -0.06, p = 3.00 × 10-4 ), consistent across oestrogen receptor-positive ( r g $$ {r}_g $$ = -0.05, p = 3.30 × 10-3 ) and oestrogen receptor-negative subtypes ( r g $$ {r}_g $$ = -0.05, p = 1.11 × 10-2 ). Five specific genomic regions were further identified as contributing a significant local genetic correlation. Cross-trait meta-analysis identified 78 loci shared between chronotype and breast cancer, of which 23 were novel. Transcriptome-wide association study revealed 13 shared genes, targeting tissues of the nervous, cardiovascular, digestive, and exocrine/endocrine systems. Mendelian randomisation demonstrated a significantly reduced risk of overall breast cancer (odds ratio 0.89, 95% confidence interval 0.83-0.94; p = 1.30 × 10-4 ) for genetically predicted morning chronotype. No reverse causality was found. Our work demonstrates an intrinsic link underlying chronotype and breast cancer, which may provide clues to inform management of sleep habits to improve female health.

16.
Eur J Neurol ; 30(7): 1854-1860, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-36940265

RESUMEN

BACKGROUND AND PURPOSE: Real-time quaking-induced conversion (RT-QuIC) assays offer a sensitive and specific means for detection of prions, although false negative results are recognized in clinical practice. We profile the clinical, laboratory, and pathologic features associated with false negative RT-QuIC assays and extend these to frame the diagnostic approach to patients with suspected prion disease. METHODS: A total of 113 patients with probable or definite prion disease were assessed at Mayo Clinic (Rochester, MN; Jacksonville, FL; Scottsdale, AZ) or Washington University School of Medicine (Saint Louis, MO) from 2013 to 2021. RT-QuIC testing for prions was performed in cerebrospinal fluid (CSF) at the National Prion Disease Pathology Surveillance Center (Cleveland, OH). RESULTS: Initial RT-QuIC testing was negative in 13 of 113 patients (sensitivity = 88.5%). RT-QuIC negative patients were younger (median = 52.0 years vs. 66.1 years, p < 0.001). Other demographic and presenting features, and CSF cell count, protein, and glucose levels were similar in RT-QuIC negative and positive patients. Frequency of 14-3-3 positivity (4/13 vs. 77/94, p < 0.001) and median CSF total tau levels were lower in RT-QuIC negative patients (2517 vs. 4001 pg/mL, p = 0.020), and time from symptom onset to first presentation (153 vs. 47 days, p = 0.001) and symptomatic duration (710 vs. 148 days, p = 0.001) were longer. CONCLUSIONS: RT-QuIC is a sensitive yet imperfect measure necessitating incorporation of other test results when evaluating patients with suspected prion disease. Patients with negative RT-QuIC had lower markers of neuronal damage (CSF total tau and protein 14-3-3) and longer symptomatic duration of disease, suggesting that false negative RT-QuIC testing associates with a more indolent course.


Asunto(s)
Síndrome de Creutzfeldt-Jakob , Enfermedades por Prión , Priones , Humanos , Priones/líquido cefalorraquídeo , Síndrome de Creutzfeldt-Jakob/diagnóstico , Sensibilidad y Especificidad , Enfermedades por Prión/diagnóstico , Proteínas 14-3-3
17.
Brain ; 145(12): 4409-4424, 2022 12 19.
Artículo en Inglés | MEDLINE | ID: mdl-35793238

RESUMEN

Huntington disease is caused by a CAG repeat expansion in exon 1 of the huntingtin gene (HTT) that is translated into a polyglutamine stretch in the huntingtin protein (HTT). We previously showed that HTT mRNA carrying an expanded CAG repeat was incompletely spliced to generate HTT1a, an exon 1 only transcript, which was translated to produce the highly aggregation-prone and pathogenic exon 1 HTT protein. This occurred in all knock-in mouse models of Huntington's disease and could be detected in patient cell lines and post-mortem brains. To extend these findings to a model system expressing human HTT, we took advantage of YAC128 mice that are transgenic for a yeast artificial chromosome carrying human HTT with an expanded CAG repeat. We discovered that the HTT1a transcript could be detected throughout the brains of YAC128 mice. We implemented RNAscope to visualize HTT transcripts at the single molecule level and found that full-length HTT and HTT1a were retained together in large nuclear RNA clusters, as well as being present as single transcripts in the cytoplasm. Homogeneous time-resolved fluorescence analysis demonstrated that the HTT1a transcript had been translated to produce the exon 1 HTT protein. The levels of exon 1 HTT in YAC128 mice, correlated with HTT aggregation, supportive of the hypothesis that exon 1 HTT initiates the aggregation process. Huntingtin-lowering strategies are a major focus of therapeutic development for Huntington's disease. These approaches often target full-length HTT alone and would not be expected to reduce pathogenic exon 1 HTT levels. We have established YAC128 mouse embryonic fibroblast lines and shown that, together with our QuantiGene multiplex assay, these provide an effective screening tool for agents that target HTT transcripts. The effects of current targeting strategies on nuclear RNA clusters are unknown, structures that may have a pathogenic role or alternatively could be protective by retaining HTT1a in the nucleus and preventing it from being translated. In light of recently halted antisense oligonucleotide trials, it is vital that agents targeting HTT1a are developed, and that the effects of HTT-lowering strategies on the subcellular levels of all HTT transcripts and their various HTT protein isoforms are understood.


Asunto(s)
Enfermedad de Huntington , Humanos , Ratones , Animales , Enfermedad de Huntington/genética , Proteína Huntingtina/genética , ARN Mensajero/metabolismo , Fibroblastos/metabolismo , ARN Nuclear , Modelos Animales de Enfermedad
18.
Prehosp Emerg Care ; 27(6): 800-806, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-35894925

RESUMEN

BACKGROUND: Respiratory distress is a common presentation attended by paramedics. Chest auscultation has been shown to have low accuracy for diagnosing respiratory complaints, and this can lead to inaccurate patient assessment and potentially poor patient outcomes. Conversely, lung ultrasound is a relatively simple exam allowing for rapid differentiation of respiratory complaints with comparable accuracy to more advanced imaging modalities. Evidence suggests that lung ultrasound is easy to learn and apply and could be ideal for assessment of respiratory illness by paramedics. OBJECTIVE: This study aimed to explore the utility of out-of-hospital lung ultrasound performed by intensive care paramedics (ICP) for patients with medical causes of respiratory distress, and explore whether the use of lung ultrasound affects the ICP's clinical impression or management. METHODS: This was a prospective observational pilot study. After a training program, a sample of ICPs working in metropolitan and regional Victoria, Australia used ultrasound to assess adult patients with respiratory distress and/or dyspnea. ICPs used a handheld point-of-care ultrasound device to scan respiratory patients using a modified protocol, and completed a worksheet with their scan findings. The scans were then reviewed by a subject matter expert for quality and agreement. RESULTS: Ninety-five patients were enrolled over the study period. The average image quality score was 2.68/5, and 56% of scans were of interpretable quality. Interrater agreement (between the ICPs and the subject matter expert) was reported using Cohen's kappa. Moderate overall agreement (0.44) was shown, with the highest reliability reported in A-profile and B-profile (0.49 and 0.57). In 42% of cases performance of the scan affected paramedic clinical impression and/or management. CONCLUSION: ICPs can perform lung ultrasound with moderate accuracy for some respiratory conditions, and the scans may affect clinical impression and management. Future research should focus on enhanced education, expert feedback, and clinical outcomes.


Asunto(s)
Servicios Médicos de Urgencia , Síndrome de Dificultad Respiratoria , Adulto , Humanos , Proyectos Piloto , Estudios Prospectivos , Paramédico , Sistemas de Atención de Punto , Reproducibilidad de los Resultados , Servicios Médicos de Urgencia/métodos , Ultrasonografía , Disnea/diagnóstico , Cuidados Críticos , Síndrome de Dificultad Respiratoria/diagnóstico por imagen , Hospitales , Victoria
19.
Br J Neurosurg ; 37(4): 627-629, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-30450992

RESUMEN

Sinonasal undifferentiated carcinoma (SNUC) is a rare and aggressive cancer of the sinonasal tract and is often characterized by intracranial invasion. However, SNUC rarely metastasizes to the spine. In this paper, we present a case of extradural metastasis and invasion of the adjacent spine by SNUC. A 42-year-old man presented to our hospital with two-month history of anosmia and nosebleeds. Imaging studies showed a neoplasm of the ethmoid sinus with extension into the anterior cranial fossa. The patient underwent resection of the carcinoma and began chemoradiotherapy. After completing chemoradiotherapy the patient complained of neck pain radiating down the right arm, and imaging showed an extradural mass at the C5 vertebral level. The patient underwent laminectomy for debulking of this tumor. One month later, the patient complained of recurrent weakness and pain in the right shoulder and arm. Imaging showed an extradural tumor wrapping around the C7 and C8 nerve roots, as well as a separate tumor at C2 adherent to the dura. The extradural tumor at C2 was surgically resected. Further imaging showed multiple new soft tissue masses at the thoracic level. We present a case of SNUC metastasis to the extradural spine representing the second case reported in the literature. Peri-dural metastasis and resulting symptoms should be included in the differential diagnosis and assessment of patients with SNUC.


Asunto(s)
Carcinoma , Neoplasias del Seno Maxilar , Masculino , Humanos , Adulto , Carcinoma/cirugía , Carcinoma/patología , Neoplasias del Seno Maxilar/patología
20.
Ecol Lett ; 25(3): 581-597, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-35199922

RESUMEN

Functional traits offer a rich quantitative framework for developing and testing theories in evolutionary biology, ecology and ecosystem science. However, the potential of functional traits to drive theoretical advances and refine models of global change can only be fully realised when species-level information is complete. Here we present the AVONET dataset containing comprehensive functional trait data for all birds, including six ecological variables, 11 continuous morphological traits, and information on range size and location. Raw morphological measurements are presented from 90,020 individuals of 11,009 extant bird species sampled from 181 countries. These data are also summarised as species averages in three taxonomic formats, allowing integration with a global phylogeny, geographical range maps, IUCN Red List data and the eBird citizen science database. The AVONET dataset provides the most detailed picture of continuous trait variation for any major radiation of organisms, offering a global template for testing hypotheses and exploring the evolutionary origins, structure and functioning of biodiversity.


Asunto(s)
Aves , Ecosistema , Animales , Biodiversidad , Evolución Biológica , Humanos , Filogenia
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