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2.
BMC Public Health ; 23(1): 420, 2023 03 02.
Artículo en Inglés | MEDLINE | ID: mdl-36864415

RESUMEN

BACKGROUND: The COVID-19 pandemic continues to demonstrate the risks and profound health impacts that result from infectious disease emergencies. Emergency preparedness has been defined as the knowledge, capacity and organizational systems that governments, response and recovery organizations, communities and individuals develop to anticipate, respond to, or recover from emergencies. This scoping review explored recent literature on priority areas and indicators for public health emergency preparedness (PHEP) with a focus on infectious disease emergencies. METHODS: Using scoping review methodology, a comprehensive search was conducted for indexed and grey literature with a focus on records published from 2017 to 2020 onward, respectively. Records were included if they: (a) described PHEP, (b) focused on an infectious emergency, and (c) were published in an Organization for Economic Co-operation and Development country. An evidence-based all-hazards Resilience Framework for PHEP consisting of 11 elements was used as a reference point to identify additional areas of preparedness that have emerged in recent publications. The findings were analyzed deductively and summarized thematically. RESULTS: The included publications largely aligned with the 11 elements of the all-hazards Resilience Framework for PHEP. In particular, the elements related to collaborative networks, community engagement, risk analysis and communication were frequently observed across the publications included in this review. Ten emergent themes were identified that expand on the Resilience Framework for PHEP specific to infectious diseases. Planning to mitigate inequities was a key finding of this review, it was the most frequently identified emergent theme. Additional emergent themes were: research and evidence-informed decision making, building vaccination capacity, building laboratory and diagnostic system capacity, building infection prevention and control capacity, financial investment in infrastructure, health system capacity, climate and environmental health, public health legislation and phases of preparedness. CONCLUSION: The themes from this review contribute to the evolving understanding of critical public health emergency preparedness actions. The themes expand on the 11 elements outlined in the Resilience Framework for PHEP, specifically relevant to pandemics and infectious disease emergencies. Further research will be important to validate these findings, and expand understanding of how refinements to PHEP frameworks and indicators can support public health practice.


Asunto(s)
COVID-19 , Defensa Civil , Enfermedades Transmisibles , Humanos , Salud Pública , COVID-19/epidemiología , Urgencias Médicas , Pandemias/prevención & control , Enfermedades Transmisibles/epidemiología , Enfermedades Transmisibles/terapia
3.
Curr Opin Struct Biol ; 79: 102544, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36804703

RESUMEN

Amino acid pools in the cell are monitored by dedicated sensors, whose structures are now coming into view. The lysosomal Rag GTPases are central to this pathway, and the regulation of their GAP complexes, FLCN-FNIP and GATOR1, have been worked out in detail. For FLCN-FNIP, the entire chain of events from the arginine transporter SLC38A9 to substrate-specific mTORC1 activation has been visualized. The structure GATOR2 has been determined, hinting at an ordering of amino acid signaling across a larger size scale than anticipated. The centerpiece of lysosomal signaling, mTORC1, has been revealed to recognize its substrates by more nuanced and substrate-specific mechanisms than previous appreciated. Beyond the well-studied Rag GTPase and mTORC1 machinery, another lysosomal amino acid sensor/effector system, that of PQLC2 and the C9orf72-containing CSW complex, is coming into structural view. These developments hold promise for further insights into lysosomal physiology and lysosome-centric therapeutics.


Asunto(s)
Aminoácidos , Proteínas de Unión al GTP Monoméricas , Aminoácidos/metabolismo , Proteínas de Unión al GTP Monoméricas/metabolismo , Transducción de Señal , Diana Mecanicista del Complejo 1 de la Rapamicina/metabolismo , Lisosomas/metabolismo
4.
FEBS Lett ; 597(6): 750-761, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36367440

RESUMEN

Small GTPases act as molecular switches and control numerous cellular processes by their binding and hydrolysis of guanosine triphosphate (GTP). The activity of small GTPases is coordinated by guanine nucleotide exchange factors (GEFs) and GTPase activating proteins (GAPs). Recent structural and functional studies have characterized a subset of GAPs whose catalytic units consist of longin domains. Longin domain containing GAPs regulate small GTPases that facilitate nutrient signalling, autophagy, vesicular trafficking and lysosome homeostasis. All known examples in this GAP family function as part of larger multiprotein complexes. The three characterized mammalian protein complexes in this class are FLCN:FNIP, GATOR1 and C9orf72:SMCR8. Each complex carries out a unique cellular function by regulating distinct small GTPases. In this article, we explore the roles of longin domain GAPs in nutrient sensing, membrane dynamic, vesicular trafficking and disease. Through a structural lens, we examine the mechanism of each longin domain GAP and highlight potential therapeutic applications.


Asunto(s)
Proteínas de Unión al GTP Monoméricas , Transducción de Señal , Animales , Proteínas de Unión al GTP Monoméricas/metabolismo , Proteínas Activadoras de GTPasa/metabolismo , Transporte de Proteínas , Nutrientes , Mamíferos/metabolismo
5.
Sci Adv ; 8(37): eadd2926, 2022 Sep 16.
Artículo en Inglés | MEDLINE | ID: mdl-36103527

RESUMEN

The mechanistic target of rapamycin complex 1 (mTORC1) regulates cell growth and catabolism in response to nutrients through phosphorylation of key substrates. The tumor suppressor folliculin (FLCN) is a RagC/D guanosine triphosphatase (GTPase)-activating protein (GAP) that regulates mTORC1 phosphorylation of MiT-TFE transcription factors, controlling lysosome biogenesis and autophagy. We determined the cryo-electron microscopy structure of the active FLCN complex (AFC) containing FLCN, FNIP2, the N-terminal tail of SLC38A9, the RagAGDP:RagCGDP.BeFx- GTPase dimer, and the Ragulator scaffold. Relative to the inactive lysosomal FLCN complex structure, FLCN reorients by 90°, breaks contact with RagA, and makes previously unseen contacts with RagC that position its Arg164 finger for catalysis. Disruption of the AFC-specific interfaces of FLCN and FNIP2 with RagC eliminated GAP activity and led to nuclear retention of TFE3, with no effect on mTORC1 substrates S6K or 4E-BP1. The structure provides a basis for regulation of an mTORC1 substrate-specific pathway and a roadmap to discover MiT-TFE family selective mTORC1 antagonists.

6.
Proc Natl Acad Sci U S A ; 118(41)2021 10 12.
Artículo en Inglés | MEDLINE | ID: mdl-34625496

RESUMEN

Heat shock protein 70 (Hsp70) chaperones bind many different sequences and discriminate between incompletely folded and folded clients. Most research into the origins of this "selective promiscuity" has relied on short peptides as substrates to dissect the binding, but much less is known about how Hsp70s bind full-length client proteins. Here, we connect detailed structural analyses of complexes between the Escherichia coli Hsp70 (DnaK) substrate-binding domain (SBD) and peptides encompassing five potential binding sites in the precursor to E. coli alkaline phosphatase (proPhoA) with SBD binding to full-length unfolded proPhoA. Analysis of SBD complexes with proPhoA peptides by a combination of X-ray crystallography, methyl-transverse relaxation optimized spectroscopy (methyl-TROSY), and paramagnetic relaxation enhancement (PRE) NMR and chemical cross-linking experiments provided detailed descriptions of their binding modes. Importantly, many sequences populate multiple SBD binding modes, including both the canonical N to C orientation and a C to N orientation. The favored peptide binding mode optimizes substrate residue side-chain compatibility with the SBD binding pockets independent of backbone orientation. Relating these results to the binding of the SBD to full-length proPhoA, we observe that multiple chaperones may bind to the protein substrate, and the binding sites, well separated in the proPhoA sequence, behave independently. The hierarchy of chaperone binding to sites on the protein was generally consistent with the apparent binding affinities observed for the peptides corresponding to these sites. Functionally, these results reveal that Hsp70s "read" sequences without regard to the backbone direction and that both binding orientations must be considered in current predictive algorithms.


Asunto(s)
Fosfatasa Alcalina/metabolismo , Proteínas de Escherichia coli/metabolismo , Escherichia coli/metabolismo , Proteínas HSP70 de Choque Térmico/metabolismo , Dominios Proteicos/fisiología , Sitios de Unión/fisiología , Cristalografía por Rayos X , Modelos Moleculares , Chaperonas Moleculares/metabolismo , Unión Proteica/fisiología , Pliegue de Proteína
7.
Proc Natl Acad Sci U S A ; 118(44)2021 11 02.
Artículo en Inglés | MEDLINE | ID: mdl-34711679

RESUMEN

Empirical audit and review is an approach to assessing the evidentiary value of a research area. It involves identifying a topic and selecting a cross-section of studies for replication. We apply the method to research on the psychological consequences of scarcity. Starting with the papers citing a seminal publication in the field, we conducted replications of 20 studies that evaluate the role of scarcity priming in pain sensitivity, resource allocation, materialism, and many other domains. There was considerable variability in the replicability, with some strong successes and other undeniable failures. Empirical audit and review does not attempt to assign an overall replication rate for a heterogeneous field, but rather facilitates researchers seeking to incorporate strength of evidence as they refine theories and plan new investigations in the research area. This method allows for an integration of qualitative and quantitative approaches to review and enables the growth of a cumulative science.


Asunto(s)
Investigación Empírica , Reproducibilidad de los Resultados , Inseguridad Alimentaria , Humanos , Dimensión del Dolor , Proyectos de Investigación , Asignación de Recursos
8.
Nat Hum Behav ; 5(6): 756-763, 2021 06.
Artículo en Inglés | MEDLINE | ID: mdl-33633375

RESUMEN

Evaluating one's own performance on a task, typically known as 'self-assessment', is perceived as a fundamental skill, but people appear poorly calibrated to their abilities. Studies seem to show poorer calibration for low performers than for high performers, which could indicate worse metacognitive ability among low performers relative to others (the Dunning-Kruger effect). By developing a rational model of self-assessment, we show that such an effect could be produced by two psychological mechanisms, in either isolation or conjunction: influence of prior beliefs about ability or a relation between performance and skill at determining correctness on each problem. To disentangle these explanations, we conducted a large-scale replication of a seminal paper with approximately 4,000 participants in each of two studies. Comparing the predictions of two variants of our rational model provides support for low performers being less able to estimate whether they are correct in the domains of grammar and logical reasoning.


Asunto(s)
Aptitud , Metacognición , Autoimagen , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad , Modelos Teóricos , Adulto Joven
9.
Cogn Sci ; 44(10): e12900, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-33063866

RESUMEN

Online educational technologies offer opportunities for providing individualized feedback and detailed profiles of students' skills. Yet many technologies for mathematics education assess students based only on the correctness of either their final answers or responses to individual steps. In contrast, examining the choices students make for how to solve the equation and the ways in which they might answer incorrectly offers the opportunity to obtain a more nuanced perspective of their algebra skills. To automatically make sense of step-by-step solutions, we propose a Bayesian inverse planning model for equation solving that computes an assessment of a learner's skills based on her pattern of errors in individual steps and her choices about what sequence of problem-solving steps to take. Bayesian inverse planning builds on existing machine learning tools to create a generative model relating (mis)-understandings to equation solving choices. Two behavioral experiments demonstrate that the model can interpret people's equation solving and that its assessments are consistent with those of experienced teachers. A third experiment uses this model to tailor guidance for learners based on individual differences in misunderstandings, closing the loop between assessing understanding, and using that assessment within an educational technology. Finally, because the bottleneck in applying inverse planning to a new domain is in creating the model of possible student misunderstandings, we show how to combine inverse planning with an existing production rule model to make inferences about student misunderstandings of fraction arithmetic.


Asunto(s)
Teorema de Bayes , Comprensión , Matemática/educación , Solución de Problemas , Estudiantes/psicología , Femenino , Humanos , Aprendizaje
10.
Oncol Rep ; 22(4): 853-61, 2009 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-19724865

RESUMEN

Ovarian cancer ranks the most lethal among gynecologic neoplasms in women. To develop potential biomarkers for diagnosis, we have identified five novel genes (CYP39A1, GTF2A1, FOXD4L4, EBP, and HAAO) that are hypermethylated in ovarian tumors, compared with the non-malignant normal ovarian surface epithelia, using the quantitative methylation-specific polymerase chain reactions. Interestingly enough, multivariate Cox regression analysis has identified hypermethylation of CYP39A1 correlated with an increase rate of relapsing (P=0.032, hazard ratio >1). Concordant hypermethylation in at least three loci was observed in 50 out of 55 (91%) of ovarian tumors examined. The test sensitivity and specificity were assessed to be 96 and 67% for CYP39A1; 95 and 88% for GTF2A1; 93 and 67% for FOXD4L4; 81 and 67% for EBP; 89 and 82% for HAAO, respectively. Our data have identified, for the first time, GTF2A1 alone, or GTF2A1 plus HAAO are excellent candidate biomarkers for detecting this disease. Moreover, the known functions of these gene products further implicate dysregulated transcriptional control, cholesterol metabolism, or synthesis of quinolinic acids, may play important roles in attributing to ovarian neoplasm. Molecular therapies, by reversing the aberrant epigenomes using inhibitory agents or by abrogating the upstream signaling pathways that convey the epigenomic perturbations, may be developed into promising treatment regimens.


Asunto(s)
Biomarcadores de Tumor/genética , Metilación de ADN/genética , Epigénesis Genética , Neoplasias Ováricas/genética , 3-Hidroxiantranilato 3,4-Dioxigenasa/genética , Islas de CpG , Femenino , Factores de Transcripción Forkhead/genética , Humanos , Persona de Mediana Edad , Estadificación de Neoplasias , Análisis de Secuencia por Matrices de Oligonucleótidos , Neoplasias Ováricas/patología , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Sensibilidad y Especificidad , Esteroide Hidroxilasas/genética , Esteroide Isomerasas/genética , Factores de Transcripción TFII/genética
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