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1.
Nat Rev Neurosci ; 2024 Jun 27.
Artículo en Inglés | MEDLINE | ID: mdl-38937654

RESUMEN

The lateral prefrontal cortex (PFC) in humans and other primates is critical for immediate, goal-directed behaviour and working memory, which are classically considered distinct from the cognitive and neural circuits that support long-term learning and memory. Over the past few years, a reconsideration of this textbook perspective has emerged, in that different timescales of memory-guided behaviour are in constant interaction during the pursuit of immediate goals. Here, we will first detail how neural activity related to the shortest timescales of goal-directed behaviour (which requires maintenance of current states and goals in working memory) is sculpted by long-term knowledge and learning - that is, how the past informs present behaviour. Then, we will outline how learning across different timescales (from seconds to years) drives plasticity in the primate lateral PFC, from single neuron firing rates to mesoscale neuroimaging activity patterns. Finally, we will review how, over days and months of learning, dense local and long-range connectivity patterns in PFC facilitate longer-lasting changes in population activity by changing synaptic weights and recruiting additional neural resources to inform future behaviour. Our Review sheds light on how the machinery of plasticity in PFC circuits facilitates the integration of learned experiences across time to best guide adaptive behaviour.

2.
J Biol Chem ; 299(8): 104939, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37331602

RESUMEN

The relationship between lipid homeostasis and protein homeostasis (proteostasis) is complex and remains incompletely understood. We conducted a screen for genes required for efficient degradation of Deg1-Sec62, a model aberrant translocon-associated substrate of the endoplasmic reticulum (ER) ubiquitin ligase Hrd1, in Saccharomyces cerevisiae. This screen revealed that INO4 is required for efficient Deg1-Sec62 degradation. INO4 encodes one subunit of the Ino2/Ino4 heterodimeric transcription factor, which regulates expression of genes required for lipid biosynthesis. Deg1-Sec62 degradation was also impaired by mutation of genes encoding several enzymes mediating phospholipid and sterol biosynthesis. The degradation defect in ino4Δ yeast was rescued by supplementation with metabolites whose synthesis and uptake are mediated by Ino2/Ino4 targets. Stabilization of a panel of substrates of the Hrd1 and Doa10 ER ubiquitin ligases by INO4 deletion indicates ER protein quality control is generally sensitive to perturbed lipid homeostasis. Loss of INO4 sensitized yeast to proteotoxic stress, suggesting a broad requirement for lipid homeostasis in maintaining proteostasis. A better understanding of the dynamic relationship between lipid homeostasis and proteostasis may lead to improved understanding and treatment of several human diseases associated with altered lipid biosynthesis.


Asunto(s)
Degradación Asociada con el Retículo Endoplásmico , Lípidos , Proteínas de Saccharomyces cerevisiae , Antiinfecciosos/farmacología , Farmacorresistencia Fúngica/genética , Degradación Asociada con el Retículo Endoplásmico/genética , Higromicina B/farmacología , Lípidos/biosíntesis , Mutación , Saccharomyces cerevisiae/efectos de los fármacos , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo
3.
Phys Rev Lett ; 132(4): 047001, 2024 Jan 26.
Artículo en Inglés | MEDLINE | ID: mdl-38335327

RESUMEN

Quantum communication test beds provide a useful resource for experimentally investigating a variety of communication protocols. Here we demonstrate a superconducting circuit test bed with bidirectional multiphoton state transfer capability using time-domain shaped wave packets. The system we use to achieve this comprises two remote nodes, each including a tunable superconducting transmon qubit and a tunable microwave-frequency resonator, linked by a 2 m-long superconducting coplanar waveguide, which serves as a transmission line. We transfer both individual and superposition Fock states between the two remote nodes, and additionally show that this bidirectional state transfer can be done simultaneously, as well as being used to entangle elements in the two nodes.

4.
Cereb Cortex ; 33(5): 1799-1813, 2023 02 20.
Artículo en Inglés | MEDLINE | ID: mdl-35589102

RESUMEN

The neuroanatomical changes that underpin cognitive development are of major interest in neuroscience. Of the many aspects of neuroanatomy to consider, tertiary sulci are particularly attractive as they emerge last in gestation, show a protracted development after birth, and are either human- or hominoid-specific. Thus, they are ideal targets for exploring morphological-cognitive relationships with cognitive skills that also show protracted development such as working memory (WM). Yet, the relationship between sulcal morphology and WM is unknown-either in development or more generally. To fill this gap, we adopted a data-driven approach with cross-validation to examine the relationship between sulcal depth in lateral prefrontal cortex (LPFC) and verbal WM in 60 children and adolescents between ages 6 and 18. These analyses identified 9 left, and no right, LPFC sulci (of which 7 were tertiary) whose depth predicted verbal WM performance above and beyond the effect of age. Most of these sulci are located within and around contours of previously proposed functional parcellations of LPFC. This sulcal depth model outperformed models with age or cortical thickness. Together, these findings build empirical support for a classic theory that tertiary sulci serve as landmarks in association cortices that contribute to late-maturing human cognitive abilities.


Asunto(s)
Imagen por Resonancia Magnética , Memoria a Corto Plazo , Adolescente , Niño , Humanos , Corteza Cerebral/anatomía & histología , Corteza Prefrontal , Cognición
5.
J Chem Phys ; 161(1)2024 Jul 07.
Artículo en Inglés | MEDLINE | ID: mdl-38958156

RESUMEN

Force Field X (FFX) is an open-source software package for atomic resolution modeling of genetic variants and organic crystals that leverages advanced potential energy functions and experimental data. FFX currently consists of nine modular packages with novel algorithms that include global optimization via a many-body expansion, acid-base chemistry using polarizable constant-pH molecular dynamics, estimation of free energy differences, generalized Kirkwood implicit solvent models, and many more. Applications of FFX focus on the use and development of a crystal structure prediction pipeline, biomolecular structure refinement against experimental datasets, and estimation of the thermodynamic effects of genetic variants on both proteins and nucleic acids. The use of Parallel Java and OpenMM combines to offer shared memory, message passing, and graphics processing unit parallelization for high performance simulations. Overall, the FFX platform serves as a computational microscope to study systems ranging from organic crystals to solvated biomolecular systems.


Asunto(s)
Programas Informáticos , Simulación de Dinámica Molecular , Variación Genética , Algoritmos , Termodinámica , Proteínas/química , Cristalización , Ácidos Nucleicos/química
6.
Biochem J ; 480(17): 1411-1427, 2023 09 13.
Artículo en Inglés | MEDLINE | ID: mdl-37622331

RESUMEN

Metabolic reprogramming, including increased glucose uptake and lactic acid excretion, is a hallmark of cancer. The glycolytic 'gatekeeper' enzyme phosphofructokinase-1 (PFK1), which catalyzes the step committing glucose to breakdown, is dysregulated in cancers. While altered PFK1 activity and expression in tumors have been demonstrated, little is known about the effects of cancer-associated somatic mutations. Somatic mutations in PFK1 inform our understanding of allosteric regulation by identifying key amino acid residues involved in the regulation of enzyme activity. Here, we characterized mutations disrupting an evolutionarily conserved salt bridge between aspartic acid and arginine in human platelet (PFKP) and liver (PFKL) isoforms. Using purified recombinant proteins, we showed that disruption of the Asp-Arg pair in two PFK1 isoforms decreased enzyme activity and altered allosteric regulation. We determined the crystal structure of PFK1 to 3.6 Šresolution and used molecular dynamic simulations to understand molecular mechanisms of altered allosteric regulation. We showed that PFKP-D564N had a decreased total system energy and changes in the electrostatic surface potential of the effector site. Cells expressing PFKP-D564N demonstrated a decreased rate of glycolysis, while their ability to induce glycolytic flux under conditions of low cellular energy was enhanced compared with cells expressing wild-type PFKP. Taken together, these results suggest that mutations in Arg-Asp pair at the interface of the catalytic-regulatory domains stabilizes the t-state and presents novel mechanistic insight for therapeutic development in cancer.


Asunto(s)
Neoplasias , Fosfofructoquinasa-1 , Humanos , Regulación Alostérica , Electricidad Estática , Fosfofructoquinasa-1/genética , Metabolismo de los Hidratos de Carbono , Neoplasias/genética
7.
Am J Physiol Heart Circ Physiol ; 324(2): H179-H197, 2023 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-36487185

RESUMEN

Many cardiac diseases are characterized by an increased late sodium current, including heart failure, hypertrophic cardiomyopathy, and inherited long QT syndrome type 3 (LQT3). The late sodium current in LQT3 is caused by a gain-of-function mutation in the voltage-gated sodium channel Nav1.5. Despite a well-defined genetic cause of LQT3, treatment remains inconsistent because of incomplete penetrance of the mutation and variability of antiarrhythmic efficacy. Here, we investigate the relationship between LQT3-associated mutation incomplete penetrance and variability in ion channel expression, simulating a population of 1,000 individuals with the O'Hara-Rudy model of the human ventricular myocyte. We first simulate healthy electrical activity (i.e., in the absence of a mutation) and then incorporate heterozygous expression for three LQT3-associated mutations (Y1795C, I1768V, and ΔKPQ), to directly compare the effects of each mutation on individuals across a diverse population. For all mutations, we find that susceptibility, defined by either the presence of an early afterdepolarization (EAD) or prolonged action potential duration (APD), primarily depends on the balance between the conductance of IKr and INa, for which individuals with a higher IKr-to-INa ratio are less susceptible. Furthermore, we find distinct differences across the population, observing individuals susceptible to zero, one, two, or all three mutations. Individuals tend to be less susceptible with an appropriate balance of repolarizing currents, typically via increased IKs or IK1. Interestingly, the more critical repolarizing current is mutation specific. We conclude that the balance between key currents plays a significant role in mutant-specific presentation of the disease phenotype in LQT3.NEW & NOTEWORTHY An in silico population approach investigates the relationship between variability in ion channel expression and gain-of-function mutations in the voltage-gated sodium channel associated with the congenital disorder long QT syndrome type 3 (LQT3). We find that ion channel variability can contribute to incomplete penetrance of the mutation, with mutant-specific differences in ion channel conductances leading to susceptibility to proarrhythmic action potential duration prolongation or early afterdepolarizations.


Asunto(s)
Síndrome de QT Prolongado , Humanos , Potenciales de Acción , Canales Iónicos/genética , Síndrome de QT Prolongado/genética , Mutación , Canal de Sodio Activado por Voltaje NAV1.5/genética , Canal de Sodio Activado por Voltaje NAV1.5/metabolismo , Penetrancia , Sodio/metabolismo , Simulación por Computador
8.
J Cancer Educ ; 38(3): 977-984, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-36083458

RESUMEN

The COVID-19 pandemic catalyzed the integration of a virtual education curriculum to support radiation oncologists in training. We report outcomes from Radiation Oncology Virtual Education Rotation (ROVER) 2.0, a supplementary virtual educational curriculum created for radiation oncology residents globally. A prospective cohort of residents completed surveys before and after the live virtual webinar sessions (pre- and post-surveys, respectively). Live sessions were structured as complex gray-zone cases across various core disease sites. Resident demographics and responses were summarized using means, standard deviations, and proportions. Nine ROVER sessions were held from October 2020 to June 2021. A total of 1487 registered residents completed the pre-survey, of which 786 attended the live case discussion and 223 completed post-surveys. A total of 479 unique radiation oncology residents (of which 95, n = 19.8%, were international attendees) from 147 institutions (national, n = 81, 55.1%; international, n = 66, 44.9%) participated in the sessions. There was similar participation across post-graduate year (PGY) 2 through 5 (range n = 86 to n = 105). Of the 122 unique resident post-surveys, nearly all reported learning through the virtual structure as "very easy" or "easy" (97.5%, n = 119). A majority rated the ROVER 2.0 educational sessions to be "valuable or "very valuable" (99.2%, n = 121), and the panelists-attendee interaction as "appropriate" (97.5%, n = 119). Virtual live didactics aimed at radiation oncology residents are feasible. These results suggest that the adoption of the ROVER 2.0 curricula may help improve radiation oncology resident education.


Asunto(s)
COVID-19 , Internado y Residencia , Oncología por Radiación , Humanos , Curriculum , Pandemias , Estudios Prospectivos , Oncología por Radiación/educación , Encuestas y Cuestionarios
9.
Can Assoc Radiol J ; 74(1): 100-109, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-35848632

RESUMEN

Purpose: The centrally restricted diffusion sign of diffusion-weighted imaging (DWI) is associated with radiation necrosis (RN) in treated gliomas. Our goal was to evaluate its diagnostic accuracy to distinguish RN from tumor recurrence (TR) in treated brain metastases. Methods: Retrospective study of consecutive patients with brain metastases who developed a newly centrally necrotic lesion after radiotherapy (RT). One reader placed regions of interest (ROI) in the enhancing solid lesion and the non-enhancing central necrosis on the apparent diffusion coefficient (ADC) map. Two readers qualitatively assessed the presence of the centrally restricted diffusion sign. The final diagnosis was made by histopathology (n = 39) or imaging follow-up (n = 2). Differences between groups were assessed by Fisher's exact or Mann-Whitney U tests. Diagnostic accuracy and inter-reader agreement were evaluated using receiver operating characteristic (ROC) curve analysis and kappa scores. Results: Forty-one lesions (32 predominant RN; 9 predominant TR) were analyzed. An ADC value ≤ 1220 × 10-6 mm2/s (sensitivity 74%, specificity 89%, area under the curve [AUC] .85 [95% confidence interval {CI}, .70-.94] P < .0001) from the necrosis and an ADC necrosis/enhancement ratio ≤1.37 (sensitivity 74%, specificity 89%, AUC .82 [95% CI, .67-.93] P < .0001) provided the highest performance for RN diagnosis. The qualitative centrally restricted diffusion sign had a sensitivity of 69% (95% CI, .50-.83), specificity of 77% (95% CI, .40-.96), and a moderate (k = .49) inter-reader agreement for RN diagnosis. Conclusions: Radiation necrosis is associated with lower ADC values in the central necrosis than TR. A moderate interobserver agreement might limit the qualitative assessment of the centrally restricted diffusion sign.


Asunto(s)
Neoplasias Encefálicas , Recurrencia Local de Neoplasia , Humanos , Estudios Retrospectivos , Recurrencia Local de Neoplasia/diagnóstico por imagen , Neoplasias Encefálicas/diagnóstico por imagen , Neoplasias Encefálicas/radioterapia , Imagen de Difusión por Resonancia Magnética/métodos , Necrosis/diagnóstico por imagen , Sensibilidad y Especificidad , Diagnóstico Diferencial
10.
S D Med ; 76(7): 294-303, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37733960

RESUMEN

INTRODUCTION: Rodeo constitutes an exciting sporting spectacle enjoyed worldwide by competitors of all ages. College rodeo encompasses nine core events: bull riding, saddle bronc riding, bareback riding, team roping, tie-down roping, breakaway roping, steer wrestling, goat tying, and barrel racing. There is little research on rodeo athletes regarding training habits, injuries during competition and/or practice, or effective injury prevention strategies. The objectives of this study were to 1) characterize the injury profile of collegiate rodeo athletes, 2) describe training practices, and 3) determine if demographic or training factors influence injury risk. METHODS: Demographic, injury, and training data from 71 National Intercollegiate Rodeo Association members was collected via a SurveyMonkey survey. Data was analyzed to determine any association with injury risk, utilizing an ANOVA test for continuous categories and chi-square test for categorical variables. RESULTS: Competing in "roughstock" events (bull riding, saddle bronc riding, and bareback riding) and wearing protective equipment were associated with increased injury risk. Injuries mirrored previous studies of contact sport athletes. Student-athletes spent most of their training in activities directly related to their event but also engaged in exercise not related to their event for a considerable amount of time each week. CONCLUSION: Rodeo competitors constitute a versatile athletic cohort at high injury risk. These findings further define the injury profile of collegiate rodeo athletes and, for the first time, describe their training habits. This information will guide event preparation and rehabilitation of injured rodeo athletes.


Asunto(s)
Atletas , Medicina , Animales , Bovinos , Masculino , Humanos , Estudiantes
11.
J Neurosci ; 41(10): 2229-2244, 2021 03 10.
Artículo en Inglés | MEDLINE | ID: mdl-33478989

RESUMEN

Understanding the relationship between neuroanatomy and function in portions of cortex that perform functions largely specific to humans such as lateral prefrontal cortex (LPFC) is of major interest in systems and cognitive neuroscience. When considering neuroanatomical-functional relationships in LPFC, shallow indentations in cortex known as tertiary sulci have been largely unexplored. Here, by implementing a multimodal approach and manually defining 936 neuroanatomical structures in 72 hemispheres (in both males and females), we show that a subset of these overlooked tertiary sulci serve as a meso-scale link between microstructural (myelin content) and functional (network connectivity) properties of human LPFC in individual participants. For example, the posterior middle frontal sulcus (pmfs) is a tertiary sulcus with three components that differ in their myelin content, resting-state connectivity profiles, and engagement across meta-analyses of 83 cognitive tasks. Further, generating microstructural profiles of myelin content across cortical depths for each pmfs component and the surrounding middle frontal gyrus (MFG) shows that both gyral and sulcal components of the MFG have greater myelin content in deeper compared with superficial layers and that the myelin content in superficial layers of the gyral components is greater than sulcal components. These findings support a classic, yet largely unconsidered theory that tertiary sulci may serve as landmarks in association cortices, as well as a modern cognitive neuroscience theory proposing a functional hierarchy in LPFC. As there is a growing need for computational tools that automatically define tertiary sulci throughout cortex, we share pmfs probabilistic sulcal maps with the field.SIGNIFICANCE STATEMENT Lateral prefrontal cortex (LPFC) is critical for functions that are thought to be specific to humans compared with other mammals. However, relationships between fine-scale neuroanatomical structures largely specific to hominoid cortex and functional properties of LPFC remain elusive. Here, we show that these structures, which have been largely unexplored throughout history, surprisingly serve as markers for anatomical and functional organization in human LPFC. These findings have theoretical, methodological, developmental, and evolutionary implications for improved understanding of neuroanatomical-functional relationships not only in LPFC, but also in association cortices more broadly. Finally, these findings ignite new questions regarding how morphological features of these neglected neuroanatomical structures contribute to functions of association cortices that are critical for human-specific aspects of cognition.


Asunto(s)
Corteza Prefrontal/anatomía & histología , Corteza Prefrontal/fisiología , Conectoma/métodos , Femenino , Humanos , Masculino
12.
Clin Infect Dis ; 74(5): 821-828, 2022 03 09.
Artículo en Inglés | MEDLINE | ID: mdl-34137815

RESUMEN

BACKGROUND: Although mRNA-based severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccines report >90% efficacy, breakthrough infections occur. Little is known about their effectiveness against SARS-CoV-2 variants, including the highly prevalent B.1.427/B.1.429 variant. METHODS: In this quality improvement project, we collected demographic and clinical information from post-vaccine SARS-CoV-2 cases (PVSCs), defined as healthcare personnel (HCP) with positive SARS-CoV-2 nucleic acid amplification test after receiving ≥1 vaccine dose. Available specimens were tested for L452R, N501Y, and E484K mutations using reverse-transcription polymerase chain reaction. Mutation prevalence was compared among unvaccinated, early post-vaccinated (≤14 days after dose 1), partially vaccinated (positive test >14 days after dose 1 and <14 days after dose 2), and fully vaccinated (>14 days after dose 2) PVSCs. RESULTS: From December 2020 to April 2021, ≥23 090 HCP received ≥1 dose of an mRNA-based SARS-CoV-2 vaccine, and 660 HCP cases of SARS-CoV-2 occurred, of which 189 were PVSCs. Among the PVSCs, 114 (60.3%), 49 (25.9%), and 26 (13.8%) were early post-vaccination, partially vaccinated, and fully vaccinated, respectively. Of 261 available samples from vaccinated and unvaccinated HCP, 103 (39.5%), including 42 PVSCs (36.5%), had the L452R mutation presumptive of B.1.427/B.1.429. When adjusted for community prevalence of B.1.427/B.1.429, PVSCs did not have significantly elevated risk of B.1.427/B.1.429 compared with unvaccinated HCP. CONCLUSIONS: Most PVSCs occurred prior to expected onset of full, vaccine-derived immunity. Presumptive B.1.427/B.1.429 was not more prevalent in post-vaccine cases than in unvaccinated SARS-CoV-2 HCP. Continued infection control measures, particularly <14 days post-vaccination, and continued variant surveillance in PVSCs are imperative to control future SARS-CoV-2 surges.


Asunto(s)
COVID-19 , SARS-CoV-2 , Centros Médicos Académicos , COVID-19/epidemiología , COVID-19/prevención & control , Vacunas contra la COVID-19 , Atención a la Salud , Humanos , Incidencia , SARS-CoV-2/genética , Vacunación
13.
Mol Cancer ; 21(1): 154, 2022 07 28.
Artículo en Inglés | MEDLINE | ID: mdl-35902864

RESUMEN

BACKGROUND: Epstein-Barr Virus (EBV)-associated nasopharyngeal carcinoma (NPC) exhibits unusual geographic restriction despite ubiquitous lifelong infection. Screening programs can detect most NPC cases at an early stage, but existing EBV diagnostics are limited by false positives and low positive predictive value (PPV), leading to excess screening endoscopies, MRIs, and repeated testing. Recent EBV genome-wide association studies (GWAS) suggest that EBV BALF2 variants account for more than 80% of attributable NPC risk. We therefore hypothesized that high-risk BALF2 variants could be readily detected in plasma for once-lifetime screening triage. METHODS: We designed and validated a multiplex genotyping assay to detect EBV BALF2 polymorphisms in human plasma. Targeted next-generation sequencing was used to validate this assay, conduct association studies with clinical phenotype, and longitudinally genotype plasma to assess within-host haplotype stability. We examined the association between NPC and BALF2 haplotypes in a large non-endemic population and three prior EBV GWAS. Finally, we estimated NPC mortality reduction, resource utilization, and cost-effectiveness of BALF2 variant-informed screening using a previously-validated cohort model. RESULTS: Following analytical validation, the BALF2 genotyping assay had 99.3% concordance with sequencing in a cohort of 24 NPC cases and 155 non-NPC controls. BALF2 haplotype was highly associated with NPC in this non-endemic population (I613V: odds ratio [OR] 7.9; V317M: OR 178.8). No other candidate BALF2 polymorphisms were significantly associated with NPC or hematologic disorders. Longitudinal genotyping revealed 97.8% within-host haplotype concordance, indicative of lifelong latent infection. In a meta-analysis of 755 NPC cases and 981 non-NPC controls, BALF2 I613V and V317M were significantly associated with NPC in both endemic and non-endemic populations. Modeled variant-informed screening strategies achieved a 46% relative increase in PPV with 7% decrease in effective screening sensitivity, thereby averting nearly half of screening endoscopies/MRIs among endemic populations in east/southeast Asia. CONCLUSIONS: EBV BALF2 haplotypes are temporally stable within hosts and can be readily detected in plasma via an inexpensive multiplex genotyping assay that offers near-perfect sequencing concordance. In endemic and non-endemic populations, I613V and V317M were highly associated with NPC and could be leveraged to develop variant-informed screening programs that mitigate false positives with small reductions in screening sensitivity.


Asunto(s)
Infecciones por Virus de Epstein-Barr , Neoplasias Nasofaríngeas , Proteínas de Unión al ADN , Infecciones por Virus de Epstein-Barr/complicaciones , Infecciones por Virus de Epstein-Barr/epidemiología , Infecciones por Virus de Epstein-Barr/genética , Estudio de Asociación del Genoma Completo , Genotipo , Herpesvirus Humano 4/genética , Humanos , Carcinoma Nasofaríngeo/diagnóstico , Carcinoma Nasofaríngeo/genética , Neoplasias Nasofaríngeas/diagnóstico , Neoplasias Nasofaríngeas/genética , Neoplasias Nasofaríngeas/patología , Proteínas Virales
14.
J Clin Microbiol ; 60(5): e0017822, 2022 05 18.
Artículo en Inglés | MEDLINE | ID: mdl-35465708

RESUMEN

The ability to distinguish between severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants of concern (VOCs) is of ongoing interest due to differences in transmissibility, responses to vaccination, clinical prognosis, and therapy. Although detailed genetic characterization requires whole-genome sequencing (WGS), targeted nucleic acid amplification tests can serve a complementary role in clinical settings, as they are more rapid and accessible than sequencing in most laboratories. We designed and analytically validated a two-reaction multiplex reverse transcription-quantitative PCR (RT-qPCR) assay targeting spike protein mutations L452R, E484K, and N501Y in reaction 1 and del69-70, K417N, and T478K in reaction 2. This assay had 95 to 100% agreement with WGS for 502 upper respiratory tract swab samples collected between 26 April 2021 and 1 August 2021, consisting of 43 Alpha, 2 Beta, 20 Gamma, 378 Delta, and 59 non-VOC infections. Validation in a separate group of 230 WGS-confirmed Omicron variant samples collected in December 2021 and January 2022 demonstrated 100% agreement. This RT-qPCR-based approach can be implemented in clinical laboratories already performing SARS-CoV-2 nucleic acid amplification tests to assist in local epidemiological surveillance and clinical decision-making.


Asunto(s)
COVID-19 , SARS-CoV-2 , COVID-19/diagnóstico , Humanos , Reacción en Cadena de la Polimerasa Multiplex , Mutación , Reacción en Cadena en Tiempo Real de la Polimerasa , Transcripción Reversa , SARS-CoV-2/genética , Glicoproteína de la Espiga del Coronavirus/genética
15.
Artículo en Inglés | MEDLINE | ID: mdl-35835515

RESUMEN

Management strategies for congenitally corrected transposition of the great arteries (ccTGA) historically consisted of a physiologic repair, resulting in the morphologic right ventricle (mRV) supporting systemic circulation. This strategy persisted despite the development of heart failure by middle age because of the reasonable short-term outcomes, and the natural history of some patients with favorable anatomy (felt to demonstrate the mRV's ability to function in the long-term), and due to the less-than-optimal outcomes associated with anatomical repair. As outcomes with anatomical repair improved, and the long-term risk of systemic mRV dysfunction became apparent, more have begun to realize its advantages. In addition to the decision on whether or not to pursue anatomical repair, and the optimal timing, studies demonstrating the nuance to morphologic left ventricle retraining have demonstrated its feasibility. Further considerations in ccTGA have begun to be better understood, including: the management of a poorly functioning mRV, systemic tricuspid valve regurgitation, the utility of morphologic left ventricle outflow tract obstruction (native or surgically created) and pacing strategies. While some considerations are apparent: biventricular pacing is superior to univentricular, tricuspid regurgitation must be managed early with either progression towards anatomical repair (pulmonary artery banding if needed for retraining) or tricuspid replacement (not repair) based on the patient's age; others remain to be completely elucidated. Overall, the heterogeneity of ccTGA, as well as the unique presentation with each patient regarding ventricular and valvular function and center-to-center variability in management strategies has made the interpretation of published data difficult. That said, more recent long-term outcomes favor anatomical repair in most situations.


Asunto(s)
Transposición de los Grandes Vasos , Insuficiencia de la Válvula Tricúspide , Transposición Congénitamente Corregida de las Grandes Arterias , Ventrículos Cardíacos , Humanos , Persona de Mediana Edad , Transposición de los Grandes Vasos/complicaciones , Transposición de los Grandes Vasos/cirugía , Resultado del Tratamiento , Insuficiencia de la Válvula Tricúspide/complicaciones
16.
Cardiol Young ; 32(10): 1547-1553, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-36148873

RESUMEN

IMPORTANCE: Single ventricle CHD affects about 5 out of 100,000 newborns, resulting in complex anatomy often requiring multiple, staged palliative surgeries. Paediatricians are an essential part of the team that cares for children with single ventricle CHD. These patients often encounter their paediatrician first when a complication arises, so it is critical to ensure the paediatrician is knowledgeable of these issues to provide optimal care. OBSERVATIONS: We reviewed the subtypes of single ventricle heart disease and the various palliative surgeries these patients undergo. We then searched the literature to detail the general paediatrician's approach to single ventricle patients at different stages of surgical palliation. CONCLUSIONS AND RELEVANCE: Single ventricle patients undergo staged palliation that drastically changes physiology after each intervention. Coordinated care between their paediatrician and cardiologist is requisite to provide excellent care. This review highlights what to expect when these patients are seen by their paediatrician for either well child visits or additional visits for parental or patient concern.


Asunto(s)
Cardiopatías Congénitas , Corazón Univentricular , Humanos , Niño , Recién Nacido , Cardiopatías Congénitas/cirugía , Cuidados Paliativos , Cuidados Posoperatorios , Pediatras , Ventrículos Cardíacos/cirugía , Estudios Retrospectivos
17.
Cardiol Young ; 32(11): 1721-1727, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-36165406

RESUMEN

IMPORTANCE: Paediatricians play an integral role in the lifelong care of children with CHD, many of whom will undergo cardiac surgery. There is a paucity of literature for the paediatrician regarding the post-operative care of such patients. OBSERVATIONS: The aim of this manuscript is to summarise essential principles and pertinent lesion-specific context for the care of patients who have undergone surgery or intervention resulting in a biventricular circulation. CONCLUSIONS AND RELEVANCE: Familiarity with common issues following cardiac surgery or intervention, as well as key details regarding specific lesions and surgeries, will aid the paediatrician in providing optimal care for these patients.


Asunto(s)
Pediatras , Niño , Humanos
18.
J Cogn Neurosci ; 33(9): 1698-1715, 2021 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-34375416

RESUMEN

Stuss considered the human PFC as a "cognitive globe" [Stuss, D. T., & Benson, D. F. Neuropsychological studies of the frontal lobes. Psychological Bulletin, 95, 3-28, 1984] on which functions of the frontal lobe could be mapped. Here, we discuss classic and recent findings regarding the evolution, development, function, and cognitive role of shallow indentations or tertiary sulci in PFC, with the goal of using tertiary sulci to map the "cognitive globe" of PFC. First, we discuss lateral PFC (LPFC) tertiary sulci in classical anatomy and modern neuroimaging, as well as their development, with a focus on those within the middle frontal gyrus. Second, we discuss tertiary sulci in comparative neuroanatomy, focusing on primates. Third, we summarize recent findings showing the utility of tertiary sulci for understanding structural-functional relationships with functional network insights in ventromedial PFC and LPFC. Fourth, we revisit and update unresolved theoretical perspectives considered by C. Vogt and O. Vogt (Allgemeinere ergebnisse unserer hirnforschung. Journal für Psychologie und Neurologie, 25, 279-462, 1919) and F. Sanides (Structure and function of the human frontal lobe. Neuropsychologia, 2, 209-219, 1964) that tertiary sulci serve as landmarks for cortical gradients. Together, the consideration of these classic and recent findings indicate that tertiary sulci are situated in a unique position within the complexity of the "cognitive globe" of PFC: They are the smallest and shallowest of sulci in PFC, yet can offer insights that bridge spatial scales (microns to networks), modalities (functional connectivity to behavior), and species. As such, the map of tertiary sulci within each individual participant serves as a coordinate system specific to that individual on which functions may be further mapped. We conclude with new theoretical and methodological questions that, if answered in future research, will likely lead to mechanistic insight regarding the structure and function of human LPFC.


Asunto(s)
Neuroimagen , Corteza Prefrontal , Animales , Cognición , Lóbulo Frontal , Humanos , Motivación
19.
Neuroimage ; 229: 117758, 2021 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-33497773

RESUMEN

The inference of cortical sulcal labels often focuses on deep (primary and secondary) sulcal regions, whereas shallow (tertiary) sulcal regions are largely overlooked in the literature due to the scarcity of manual/well-defined annotations and their large neuroanatomical variability. In this paper, we present an automated framework for regional labeling of both primary/secondary and tertiary sulci of the dorsal portion of lateral prefrontal cortex (LPFC) using spherical convolutional neural networks. We propose two core components that enhance the inference of sulcal labels to overcome such large neuroanatomical variability: (1) surface data augmentation and (2) context-aware training. (1) To take into account neuroanatomical variability, we synthesize training data from the proposed feature space that embeds intermediate deformation trajectories of spherical data in a rigid to non-rigid fashion, which bridges an augmentation gap in conventional rotation data augmentation. (2) Moreover, we design a two-stage training process to improve labeling accuracy of tertiary sulci by informing the biological associations in neuroanatomy: inference of primary/secondary sulci and then their spatial likelihood to guide the definition of tertiary sulci. In the experiments, we evaluate our method on 13 deep and shallow sulci of human LPFC in two independent data sets with different age ranges: pediatric (N=60) and adult (N=36) cohorts. We compare the proposed method with a conventional multi-atlas approach and spherical convolutional neural networks without/with rotation data augmentation. In both cohorts, the proposed data augmentation improves labeling accuracy of deep and shallow sulci over the baselines, and the proposed context-aware training offers further improvement in the labeling of shallow sulci over the proposed data augmentation. We share our tools with the field and discuss applications of our results for understanding neuroanatomical-functional organization of LPFC and the rest of cortex (https://github.com/ilwoolyu/SphericalLabeling).


Asunto(s)
Conectoma/métodos , Análisis de Datos , Procesamiento de Imagen Asistido por Computador/métodos , Imagen por Resonancia Magnética/métodos , Corteza Prefrontal/diagnóstico por imagen , Corteza Prefrontal/fisiología , Adolescente , Adulto , Niño , Femenino , Humanos , Masculino , Adulto Joven
20.
Emerg Infect Dis ; 27(1)2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-33183494

RESUMEN

Pooled nucleic acid amplification tests for severe acute respiratory syndrome coronavirus 2 could increase availability of testing at decreased cost. However, the effect of dilution on analytical sensitivity through sample pooling has not been well characterized. We tested 1,648 prospectively pooled specimens by using 3 nucleic acid amplification tests for severe acute respiratory syndrome coronavirus 2: a laboratory-developed real-time reverse transcription PCR targeting the envelope gene, and 2 commercially available Panther System assays targeting open reading frame 1ab. Positive percent agreement (PPA) of pooled versus individual testing ranged from 71.7% to 82.6% for pools of 8 and from 82.9% to 100.0% for pools of 4. We developed and validated an independent stochastic simulation model to estimate effects of dilution on PPA and efficiency of a 2-stage pooled real-time reverse transcription PCR testing algorithm. PPA was dependent on the proportion of tests with positive results, cycle threshold distribution, and assay limit of detection.


Asunto(s)
Prueba de COVID-19/métodos , COVID-19/diagnóstico , Técnicas de Amplificación de Ácido Nucleico/métodos , SARS-CoV-2/aislamiento & purificación , COVID-19/virología , Técnicas de Laboratorio Clínico/métodos , Reacciones Falso Negativas , Humanos , Técnicas de Diagnóstico Molecular/métodos , Técnicas de Amplificación de Ácido Nucleico/normas , Estudios Prospectivos , SARS-CoV-2/genética , Sensibilidad y Especificidad , Manejo de Especímenes , Procesos Estocásticos
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