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1.
Am J Hum Genet ; 109(10): 1789-1813, 2022 10 06.
Artículo en Inglés | MEDLINE | ID: mdl-36152629

RESUMEN

Chromosome 16p11.2 reciprocal genomic disorder, resulting from recurrent copy-number variants (CNVs), involves intellectual disability, autism spectrum disorder (ASD), and schizophrenia, but the responsible mechanisms are not known. To systemically dissect molecular effects, we performed transcriptome profiling of 350 libraries from six tissues (cortex, cerebellum, striatum, liver, brown fat, and white fat) in mouse models harboring CNVs of the syntenic 7qF3 region, as well as cellular, transcriptional, and single-cell analyses in 54 isogenic neural stem cell, induced neuron, and cerebral organoid models of CRISPR-engineered 16p11.2 CNVs. Transcriptome-wide differentially expressed genes were largely tissue-, cell-type-, and dosage-specific, although more effects were shared between deletion and duplication and across tissue than expected by chance. The broadest effects were observed in the cerebellum (2,163 differentially expressed genes), and the greatest enrichments were associated with synaptic pathways in mouse cerebellum and human induced neurons. Pathway and co-expression analyses identified energy and RNA metabolism as shared processes and enrichment for ASD-associated, loss-of-function constraint, and fragile X messenger ribonucleoprotein target gene sets. Intriguingly, reciprocal 16p11.2 dosage changes resulted in consistent decrements in neurite and electrophysiological features, and single-cell profiling of organoids showed reciprocal alterations to the proportions of excitatory and inhibitory GABAergic neurons. Changes both in neuronal ratios and in gene expression in our organoid analyses point most directly to calretinin GABAergic inhibitory neurons and the excitatory/inhibitory balance as targets of disruption that might contribute to changes in neurodevelopmental and cognitive function in 16p11.2 carriers. Collectively, our data indicate the genomic disorder involves disruption of multiple contributing biological processes and that this disruption has relative impacts that are context specific.


Asunto(s)
Trastorno del Espectro Autista , Trastornos de los Cromosomas , Discapacidad Intelectual , Animales , Trastorno del Espectro Autista/genética , Calbindina 2/genética , Corteza Cerebral , Deleción Cromosómica , Trastornos de los Cromosomas/genética , Cromosomas Humanos Par 16/genética , Variaciones en el Número de Copia de ADN , Genómica , Humanos , Discapacidad Intelectual/genética , Ratones , Neuronas , ARN
2.
Stroke ; 55(10): 2558-2566, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-39212043

RESUMEN

Transient ischemic attack (TIA) is traditionally viewed as a self-resolving episode of neurological change without persistent impairments and without evidence of acute brain injury on neuroimaging. However, emerging evidence suggests that TIA may be associated with lingering cognitive dysfunction. Cognitive impairment is a prevalent and disabling sequela of ischemic stroke, but the clinical relevance of this phenomenon after TIA is less commonly recognized. We performed a literature search of observational studies of cognitive function after TIA. There is a consistent body of literature suggesting that rates of cognitive impairment following TIA are higher than healthy controls, but the studies included here are limited by heterogeneity in design and analysis methods. We go on to summarize recent literature on proposed pathophysiological mechanisms underlying the development of cognitive impairment following TIA and finally suggest future directions for further research in this field.


Asunto(s)
Disfunción Cognitiva , Ataque Isquémico Transitorio , Humanos , Ataque Isquémico Transitorio/complicaciones , Ataque Isquémico Transitorio/psicología , Disfunción Cognitiva/etiología , Disfunción Cognitiva/fisiopatología
3.
J Neuroinflammation ; 21(1): 163, 2024 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-38918792

RESUMEN

BACKGROUND: The SARS-CoV-2 virus activates maternal and placental immune responses. Such activation in the setting of other infections during pregnancy is known to impact fetal brain development. The effects of maternal immune activation on neurodevelopment are mediated at least in part by fetal brain microglia. However, microglia are inaccessible for direct analysis, and there are no validated non-invasive surrogate models to evaluate in utero microglial priming and function. We have previously demonstrated shared transcriptional programs between microglia and Hofbauer cells (HBCs, or fetal placental macrophages) in mouse models. METHODS AND RESULTS: We assessed the impact of maternal SARS-CoV-2 on HBCs isolated from 24 term placentas (N = 10 SARS-CoV-2 positive cases, 14 negative controls). Using single-cell RNA-sequencing, we demonstrated that HBC subpopulations exhibit distinct cellular programs, with specific subpopulations differentially impacted by SARS-CoV-2. Assessment of differentially expressed genes implied impaired phagocytosis, a key function of both HBCs and microglia, in some subclusters. Leveraging previously validated models of microglial synaptic pruning, we showed that HBCs isolated from placentas of SARS-CoV-2 positive pregnancies can be transdifferentiated into microglia-like cells (HBC-iMGs), with impaired synaptic pruning behavior compared to HBC models from negative controls. CONCLUSION: These findings suggest that HBCs isolated at birth can be used to create personalized cellular models of offspring microglial programming.


Asunto(s)
COVID-19 , Macrófagos , Microglía , Placenta , Complicaciones Infecciosas del Embarazo , SARS-CoV-2 , Femenino , Embarazo , Microglía/virología , Humanos , Placenta/virología , COVID-19/inmunología , Macrófagos/virología , Complicaciones Infecciosas del Embarazo/virología , Complicaciones Infecciosas del Embarazo/patología , SARS-CoV-2/patogenicidad , Feto , Adulto , Encéfalo/virología , Encéfalo/patología , Ratones , Animales
4.
Artículo en Inglés | MEDLINE | ID: mdl-38953220

RESUMEN

INTRODUCTION: Patient-reported outcomes (PROs) are increasingly used to evaluate quality of life (QoL) in Atrial Fibrillation (AF) patients, providing crucial insights in clinical trials. This study examines the frequency of PRO use in AF trials and the linguistic accessibility of AF-specific PROs. BACKGROUND: As the United States becomes more multilingual, ensuring PROs are available in various languages is vital. The number of people speaking a language other than English at home has tripled from 23.1 million in 1980 to 67.8 million in 2019. This diversity necessitates the availability of PROs in multiple languages for inclusive clinical assessments. METHODS: We queried ClinicalTrials.gov for all US interventional AF trials up to November 28, 2023, reviewing each for PRO usage as primary or secondary outcomes. We identified the five most common AF-specific and generic PROs, extracting their available translations and original languages from published sources. RESULTS: Of 233 identified trials, 191 had associated publications, with 180 (94.2%) conducted solely in English. Only one trial (0.4%) used an AF-specific PRO as a primary outcome, compared to four (1.7%) with a generic PRO. Ten trials (4.3%) used AF-specific PROs as secondary endpoints, versus 22 (9.4%) using generic PROs. AF-specific PROs had significantly fewer translations than generic PROs (11.2 vs. 148.8; p < .001). The AF Effect on Quality-of-Life (AFEQT) was available in 24 languages, with limited translations in commonly spoken US languages like Arabic and Asian languages. CONCLUSION: The limited availability of AF-specific PRO translations highlights a barrier to inclusive AF clinical trials. Expanding translations for AF-specific PROs is crucial for equitable QoL assessments.

5.
Mol Psychiatry ; 2023 Jul 04.
Artículo en Inglés | MEDLINE | ID: mdl-37402854

RESUMEN

While most of the efforts to uncover mechanisms contributing to bipolar disorder (BD) focused on phenotypes at the mature neuron stage, little research has considered events that may occur during earlier timepoints of neurodevelopment. Further, although aberrant calcium (Ca2+) signaling has been implicated in the etiology of this condition, the possible contribution of store-operated Ca2+ entry (SOCE) is not well understood. Here, we report Ca2+ and developmental dysregulations related to SOCE in BD patient induced pluripotent stem cell (iPSC)-derived neural progenitor cells (BD-NPCs) and cortical-like glutamatergic neurons. First, using a Ca2+ re-addition assay we found that BD-NPCs and neurons had attenuated SOCE. Intrigued by this finding, we then performed RNA-sequencing and uncovered a unique transcriptome profile in BD-NPCs suggesting accelerated neurodifferentiation. Consistent with these results, we measured a slower rate of proliferation, increased neurite outgrowth, and decreased size in neurosphere formations with BD-NPCs. Also, we observed decreased subventricular areas in developing BD cerebral organoids. Finally, BD NPCs demonstrated high expression of the let-7 family while BD neurons had increased miR-34a, both being microRNAs previously implicated in neurodevelopmental deviations and BD etiology. In summary, we present evidence supporting an accelerated transition towards the neuronal stage in BD-NPCs that may be indicative of early pathophysiological features of the disorder.

6.
Mol Psychiatry ; 2023 Nov 08.
Artículo en Inglés | MEDLINE | ID: mdl-37938767

RESUMEN

Neurodevelopmental changes and impaired stress resistance have been implicated in the pathogenesis of bipolar disorder (BD), but the underlying regulatory mechanisms are unresolved. Here we describe a human cerebral organoid model of BD that exhibits altered neural development, elevated neural network activity, and a major shift in the transcriptome. These phenotypic changes were reproduced in cerebral organoids generated from iPS cell lines derived in different laboratories. The BD cerebral organoid transcriptome showed highly significant enrichment for gene targets of the transcriptional repressor REST. This was associated with reduced nuclear REST and REST binding to target gene recognition sites. Reducing the oxygen concentration in organoid cultures to a physiological range ameliorated the developmental phenotype and restored REST expression. These effects were mimicked by treatment with lithium. Reduced nuclear REST and derepression of REST targets genes were also observed in the prefrontal cortex of BD patients. Thus, an impaired cellular stress response in BD cerebral organoids leads to altered neural development and transcriptional dysregulation associated with downregulation of REST. These findings provide a new model and conceptual framework for exploring the molecular basis of BD.

7.
J Neuropsychiatry Clin Neurosci ; : appineuropsych20230190, 2024 Aug 22.
Artículo en Inglés | MEDLINE | ID: mdl-39169740

RESUMEN

OBJECTIVE: Responsive and human-centered neurotechnology development requires attention to public perceptions, particularly among groups underserved by existing treatments. METHODS: The authors conducted a preregistered nationally representative survey (https://osf.io/ej9h2) using the NORC at the University of Chicago AmeriSpeak panel. One vignette compared an implanted neural device with surgical resection in a scenario involving epilepsy, and another compared an implanted neural device with medications in a scenario involving mood disorders. The survey also contained questions about respondents' confidence that a device would be available if needed and confidence that enough research has been conducted among people like themselves. Responses were entered into nested survey-weighted logistic regression models, including a base demographic model (to test the overall effect of demographic factors) and an adjusted model that also included socioeconomic, religious and political, and health care access predictors. RESULTS: A total of 1,047 adults responded to the survey, which oversampled Black non-Hispanic (N=214), Hispanic (N=210), and rural (N=219) Americans. In the base demographic model, older Americans were more likely to prefer an implanted device in the two scenarios, and non-Hispanic Black Americans were less likely than non-Hispanic White Americans to prefer a device; rural Americans were less confident than urban or suburban Americans in having access, and non-Hispanic Black and rural Americans were less confident that enough research has been conducted among people like themselves. In adjusted models, income was a key mediator, partially explaining the effect of age and the contrast between Black and White non-Hispanic respondents on preferences for a device in the epilepsy scenario and fully explaining the effect of rurality on confidence in access. CONCLUSIONS: Demographic differences in prospective preferences and concerns highlight the importance of including members of underserved communities in neurotechnology development.

8.
Cogn Behav Neurol ; 37(2): 49-56, 2024 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-38717325

RESUMEN

Behavioral neurology & neuropsychiatry (BNNP) is a field that seeks to understand brain-behavior relationships, including fundamental brain organization principles and the many ways that brain structures and connectivity can be disrupted, leading to abnormalities of behavior, cognition, emotion, perception, and social cognition. In North America, BNNP has existed as an integrated subspecialty through the United Council for Neurologic Subspecialties since 2006. Nonetheless, the number of behavioral neurologists across academic medical centers and community settings is not keeping pace with increasing clinical and research demand. In this commentary, we provide a brief history of BNNP followed by an outline of the current challenges and opportunities for BNNP from the behavioral neurologist's perspective across clinical, research, and educational spheres. We provide a practical guide for promoting BNNP and addressing the shortage of behavioral neurologists to facilitate the continued growth and development of the subspecialty. We also urge a greater commitment to recruit trainees from diverse backgrounds so as to dismantle persistent obstacles that hinder inclusivity in BNNP-efforts that will further enhance the growth and impact of the subspecialty. With rapidly expanding diagnostic and therapeutic approaches across a range of conditions at the intersection of neurology and psychiatry, BNNP is well positioned to attract new trainees and expand its reach across clinical, research, and educational activities.


Asunto(s)
Neurología , Humanos , Neurología/tendencias , Neuropsiquiatría/tendencias
9.
Am J Perinatol ; 41(13): 1808-1814, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-38301722

RESUMEN

OBJECTIVE: Maternal risk stratification systems are increasingly employed in predicting and preventing obstetric complications. These systems focus primarily on maternal morbidity, and few tools exist to stratify neonatal risk. We sought to determine if a maternal risk stratification score was associated with neonatal morbidity. STUDY DESIGN: Retrospective cohort study of patients with liveborn infants born at ≥24 weeks at four hospitals in one health system between January 1, 2020, and December 31, 2020. The Expanded Obstetric Comorbidity Score (EOCS) is used as the maternal risk score. The primary neonatal outcome was 5-minute Apgar <7. Logistic regression models determined associations between EOCS and neonatal morbidity. Secondary analyses were performed, including stratifying outcomes by gestational age and limiting analysis to "low-risk" term singletons. Model discrimination assessed using the area under the receiver operating characteristic curves (AUC) and calibration via calibration plots. RESULTS: A total of 14,497 maternal-neonatal pairs were included; 236 (1.6%) had 5-minute Apgar <7; EOCS was higher in 5-minute Apgar <7 group (median 41 vs. 11, p < 0.001). AUC for EOCS in predicting Apgar <7 was 0.72 (95% Confidence Interval (CI) 0.68, 0.75), demonstrating relatively good discrimination. Calibration plot revealed that those in the highest EOCS decile had higher risk of neonatal morbidity (7.6 vs. 1.7%, p < 0.001). When stratified by gestational age, discrimination weakened with advancing gestational age: AUC 0.70 for <28 weeks, 0.63 for 28 to 31 weeks, 0.64 for 32 to 36 weeks, and 0.61 for ≥37 weeks. When limited to term low-risk singletons, EOCS had lower discrimination for predicting neonatal morbidity and was not well calibrated. CONCLUSION: A maternal morbidity risk stratification system does not perform well in most patients giving birth, at low risk for neonatal complications. The findings suggest that the association between EOCS and 5-minute Apgar <7 likely reflects a relationship with prematurity. This study cautions against intentional or unintentional extrapolation of maternal morbidity risk for neonatal risk, especially for term deliveries. KEY POINTS: · EOCS had moderate discrimination for Apgar <7.. · Predictive performance declined when limited to low-risk term singletons.. · Relationship between EOCS and Apgar <7 was likely driven by prematurity..


Asunto(s)
Puntaje de Apgar , Humanos , Femenino , Recién Nacido , Estudios Retrospectivos , Medición de Riesgo/métodos , Embarazo , Adulto , Edad Gestacional , Modelos Logísticos , Curva ROC , Complicaciones del Embarazo/epidemiología , Masculino , Enfermedades del Recién Nacido/epidemiología
10.
Ann Pharm Fr ; 82(2): 318-328, 2024 Mar.
Artículo en Francés | MEDLINE | ID: mdl-38160789

RESUMEN

INTRODUCTION: The proper use of antimicrobials is a challenge in healthcare establishments. OBJECTIVES: Describe the detailed antimicrobial consumption profile in 2021-2022. Describe the annual evolutionary profile of the use of antimicrobials in days of therapy/1000 patient days, antibiotic spectrum index/1000 patients days and according to the proportion of days of therapy administered by parenteral route from 2005-2006 to 2021-2022. METHOD: Descriptive and retrospective study. All patients admitted to our mother-child hospital center between April 1, 2005 and March 31, 2022 were included. The study covers the consumption of all antimicrobials through the AWare classification of the World Health Organization and antibiotic spectrum index. RESULTS: A total of 673.9 days of therapy/1000 patients days was calculated in 2021-2022, i.e. 550.8 for antibiotics, 46.5 for antivirals, 67.9 for antifungals and 8.7 for others. A total of 2436 ASI/1000 patient days was calculated in 2021-2021. According to the AWaRe classification, in 2021-2022, 52.1% (287/551) of days of therapy/1000 patients days referred to the "Access" group, 47.8% (263/551) to the "Watch" group and 0.2% (1/551) to the "Reserve" group. CONCLUSION: This study aims to explore the use of antimicrobials in a mother-child hospital center. It puts into perspective a stable or even slightly decreasing use of a selection of antimicrobials and compares favorably with published data. Antibiotic governance is based in particular on the periodic evaluation of consumption. Our study illustrates different approaches to quantify and describe this use.


Asunto(s)
Antiinfecciosos , Humanos , Estudios Retrospectivos , Antiinfecciosos/uso terapéutico , Antibacterianos/uso terapéutico , Hospitales Universitarios , Canadá , Relaciones Madre-Hijo
11.
J Am Chem Soc ; 145(17): 9729-9736, 2023 05 03.
Artículo en Inglés | MEDLINE | ID: mdl-37071757

RESUMEN

Site-specific recombination is a cellular process for the integration, inversion, and excision of DNA segments that could be tailored for memory transactions in artificial cells. Here, we demonstrate the compartmentalization of cascaded gene expression reactions in a DNA brush, starting from the cell-free synthesis of a unidirectional recombinase that exchanges information between two DNA molecules, leading to gene expression turn-on/turn-off. We show that recombination yield in the DNA brush was responsive to gene composition, density, and orientation, with kinetics faster than in a homogeneous dilute bulk solution reaction. Recombination yield scaled with a power law greater than 1 with respect to the fraction of recombining DNA polymers in a dense brush. The exponent approached either 1 or 2, depending on the intermolecular distance in the brush and the position of the recombination site along the DNA contour length, suggesting that a restricted-reach effect between the recombination sites governs the recombination yield. We further demonstrate the ability to encode the DNA recombinase in the same DNA brush with its substrate constructs, enabling multiple spatially resolved orthogonal recombination transactions within a common reaction volume. Our results highlight the DNA brush as a favorable compartment to study DNA recombination, with unique properties for encoding autonomous memory transactions in DNA-based artificial cells.


Asunto(s)
Polímeros , Recombinación Genética , ADN/genética , Conformación Molecular , Recombinasas
12.
Mol Psychiatry ; 27(9): 3898-3903, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-35705635

RESUMEN

Neuropsychiatric symptoms may persist following acute COVID-19 illness, but the extent to which these symptoms are specific to COVID-19 has not been established. We utilized electronic health records across 6 hospitals in Massachusetts to characterize cohorts of individuals discharged following admission for COVID-19 between March 2020 and May 2021, and compared them to individuals hospitalized for other indications during this period. Natural language processing was applied to narrative clinical notes to identify neuropsychiatric symptom domains up to 150 days following hospitalization, in addition to those reflected in diagnostic codes as measured in prior studies. Among 6619 individuals hospitalized for COVID-19 drawn from a total of 42,961 hospital discharges, the most commonly-documented symptom domains between 31 and 90 days after initial positive test were fatigue (13.4%), mood and anxiety symptoms (11.2%), and impaired cognition (8.0%). In regression models adjusted for sociodemographic features and hospital course, none of these were significantly more common among COVID-19 patients; indeed, mood and anxiety symptoms were less frequent (adjusted OR 0.72 95% CI 0.64-0.92). Between 91 and 150 days after positivity, most commonly-detected symptoms were fatigue (10.9%), mood and anxiety symptoms (8.2%), and sleep disruption (6.8%), with impaired cognition in 5.8%. Frequency was again similar among non-COVID-19 post-hospital patients, with mood and anxiety symptoms less common (aOR 0.63, 95% CI 0.52-0.75). Propensity-score matched analyses yielded similar results. Overall, neuropsychiatric symptoms were common up to 150 days after initial hospitalization, but occurred at generally similar rates among individuals hospitalized for other indications during the same period. Post-acute sequelae of COVID-19 may benefit from standard if less-specific treatments developed for rehabilitation after hospitalization.


Asunto(s)
COVID-19 , Humanos , Estudios de Casos y Controles , Registros Electrónicos de Salud , Hospitalización , Fatiga
13.
Mol Psychiatry ; 27(10): 3939-3950, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-36198765

RESUMEN

Neuropsychiatric manifestations are common in both the acute and post-acute phase of SARS-CoV-2 infection, but the mechanisms of these effects are unknown. In a newly established brain organoid model with innately developing microglia, we demonstrate that SARS-CoV-2 infection initiate neuronal cell death and cause a loss of post-synaptic termini. Despite limited neurotropism and a decelerating viral replication, we observe a threefold increase in microglial engulfment of postsynaptic termini after SARS-CoV-2 exposure. We define the microglial responses to SARS-CoV-2 infection by single cell transcriptomic profiling and observe an upregulation of interferon-responsive genes as well as genes promoting migration and synapse engulfment. To a large extent, SARS-CoV-2 exposed microglia adopt a transcriptomic profile overlapping with neurodegenerative disorders that display an early synapse loss as well as an increased incident risk after a SARS-CoV-2 infection. Our results reveal that brain organoids infected with SARS-CoV-2 display disruption in circuit integrity via microglia-mediated synapse elimination and identifies a potential novel mechanism contributing to cognitive impairments in patients recovering from COVID-19.


Asunto(s)
COVID-19 , SARS-CoV-2 , Humanos , Organoides , Microglía , Encéfalo , Terminales Presinápticos
14.
J Child Psychol Psychiatry ; 64(10): 1480-1491, 2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-37263773

RESUMEN

BACKGROUND: Longitudinal studies show that lower cognitive performance in adolescence and early adulthood is associated with higher risk of suicide death throughout adulthood. However, it is unclear whether this cognitive vulnerability originates earlier in childhood since studies conducted in children are scarce and have inconsistent results. METHODS: Vital status of 49,853 individuals born between 1959 and 1966 to participants in the Collaborative Perinatal Project cohort was determined by a probabilistic linkage to the National Death Index, covering all US deaths occurring from 1979 through 2016. Cox proportional hazard models were used to examine associations of general, verbal, and non-verbal intelligence at ages 4 and 7, and academic skills at age 7 with suicide death coded according to ICD-9/10 criteria, while accounting for sociodemographic and pregnancy factors previously associated with suicide in this sample. RESULTS: By the end of 2016, 288 cohort members had died by suicide. Cognitive performance at 7 years on tests with verbal components was associated with suicide risk (average vs. high verbal intelligence, HR = 1.97, 95% CI 1.05-3.71; low vs. high spelling skills, HR = 2.02, 95% CI 1.16-3.51; low vs. high reading skills, HR = 2.01, 95% CI 1.27-3.17). Associations were still evident, especially for verbal intelligence and reading skills, but hazard ratios were attenuated after adjusting for prenatal and sociodemographic factors at birth (verbal intelligence, HR = 1.97, 95% CI 1.03-3.78; spelling, HR = 1.61, 95% CI 0.90-2.88; reading, HR = 1.67, 95% CI 1.02-2.72). CONCLUSIONS: Childhood neurocognitive performance is associated with vulnerability to suicide mortality through middle-adulthood, suggesting that there might be a cognitive diathesis for suicide originating in early childhood. Future studies should examine how multiple domains of childhood cognitive performance contribute to vulnerability to suicide risk, including by increasing risk for social and environmental factors that are associated not only with suicide but also with many types of psychiatric disorders.


Asunto(s)
Trastornos Mentales , Suicidio , Recién Nacido , Femenino , Embarazo , Adolescente , Humanos , Niño , Preescolar , Adulto , Susceptibilidad a Enfermedades , Estudios Longitudinales , Cognición
15.
Microb Cell Fact ; 22(1): 244, 2023 Nov 30.
Artículo en Inglés | MEDLINE | ID: mdl-38037098

RESUMEN

Protein complex assembly facilitates the combination of individual protein subunits into functional entities, and thus plays a crucial role in biology and biotechnology. Recently, we developed quasi-twodimensional, silicon-based compartmental biochips that are designed to study and administer the synthesis and assembly of protein complexes. At these biochips, individual protein subunits are synthesized from locally confined high-density DNA brushes and are captured on the chip surface by molecular traps. Here, we investigate single-gene versions of our quasi-twodimensional synthesis systems and introduce the trap-binding efficiency to characterize their performance. We show by mathematical and computational modeling how a finite trap density determines the dynamics of protein-trap binding and identify three distinct regimes of the trap-binding efficiency. We systematically study how protein-trap binding is governed by the system's three key parameters, which are the synthesis rate, the diffusion constant and the trap-binding affinity of the expressed protein. In addition, we describe how spatially differential patterns of traps modulate the protein-trap binding dynamics. In this way, we extend the theoretical knowledge base for synthesis, diffusion, and binding in compartmental systems, which helps to achieve better control of directed molecular self-assembly required for the fabrication of nanomachines for synthetic biology applications or nanotechnological purposes.


Asunto(s)
Nanotecnología , Biosíntesis de Proteínas , Subunidades de Proteína , Nanotecnología/métodos , Simulación por Computador , Silicio
16.
Am J Bot ; 110(10): e16229, 2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-37661805

RESUMEN

PREMISE: The Amazonian hyperdominant genus Eperua (Fabaceae) currently holds 20 described species and has two strongly different inflorescence and flower types, with corresponding different pollination syndrome. The evolution of these vastly different inflorescence types within this genus was unknown and the main topic in this study. METHODS: We constructed a molecular phylogeny, based on the full nuclear ribosomal DNA and partial plastome, using Bayesian inference and maximum likelihood methods, to test whether the genus is monophyletic, whether all species are monophyletic and if the shift from bat to bee pollination (or vice versa) occurred once in this genus. RESULTS: All but two species are well supported by the nuclear ribosomal phylogeny. The plastome phylogeny, however, shows a strong geographic signal suggesting strong local hybridization or chloroplast capture, rendering chloroplast barcodes meaningless in this genus. CONCLUSIONS: With our data, we cannot fully resolve the backbone of the tree to clarify sister genera relationships and confirm monophyly of the genus Eperua. Within the genus, the shift from bat to bee and bee to bat pollination has occurred several times but, with the bee to bat not always leading to a pendant inflorescence.


Asunto(s)
Quirópteros , Fabaceae , Abejas/genética , Animales , Filogenia , Inflorescencia/genética , Teorema de Bayes , Análisis de Secuencia de ADN , Evolución Molecular
17.
Am J Perinatol ; 2023 Feb 16.
Artículo en Inglés | MEDLINE | ID: mdl-36608698

RESUMEN

OBJECTIVE: The aim of this study was to determine if a universally applied risk score threshold for severe maternal morbidity (SMM) resulted in different performance characteristics among subgroups of the population. STUDY DESIGN: This is a retrospective cohort study of deliveries that occurred between July 1, 2016, and June 30, 2020, in a single health system. We examined the performance of a validated comorbidity score to stratify SMM risk in our cohort. We considered the risk score that was associated with the highest decile of predicted risk as a "screen positive" for morbidity. We then used this same threshold to calculate the sensitivity and positive predictive value (PPV) of this "highest risk" designation among subgroups of the overall cohort based on the following characteristics: age, race/ethnicity, parity, gestational age, and planned mode of delivery. RESULTS: In the overall cohort of 53,982 women, the C-statistic was 0.755 (95% confidence interval [CI], 0.741-0.769) and calibration plot demonstrated that the risk score was well calibrated. The model performed less well in the following groups: non-White or Hispanic (C-statistic, 0.734; 95% CI, 0.712-0.755), nulliparas (C-statistic, 0.735; 95% CI, 0.716-0.754), term deliveries (C-statistic, 0.712; 95% CI, 0.694-0.729), and planned vaginal delivery (C-statistic, 0.728; 95% CI, 0.709-0.747). There were differences in the PPVs by gestational age (7.8% term and 29.7% preterm) and by planned mode of delivery (8.7% vaginal and 17.7% cesarean delivery). Sensitivities were lower in women who were <35 years (36.6%), non-White or Hispanic (40.7%), nulliparous (38.9%), and those having a planned vaginal delivery (40.9%) than their counterparts. CONCLUSION: The performance of a risk score for SMM can vary by population subgroups when using standard thresholds derived from the overall cohort. If applied without such considerations, such thresholds may be less likely to identify certain subgroups of the population that may be at increased risk of SMM. KEY POINTS: · Predictive risk models are helpful at condensing complex information into an interpretable output.. · Model performance may vary among different population subgroups.. · Prediction models should be examined for their potential to exacerbate underlying disparities..

18.
Sensors (Basel) ; 23(20)2023 Oct 21.
Artículo en Inglés | MEDLINE | ID: mdl-37896719

RESUMEN

Magnetoelectric (ME)-based magnetometers have garnered much attention as they boast ultra-low-power systems with a small form factor and limit of detection in the tens of picotesla. The highly sensitive and low-power electric readout from the ME sensor makes them attractive for near DC and low-frequency AC magnetic fields as platforms for continuous magnetic signature monitoring. Among multiple configurations of the current ME magnetic sensors, most rely on exploiting the mechanically resonant characteristics of a released ME microelectromechanical system (MEMS) in a heterostructure device. Through optimizing the resonant device configuration, we design and fabricate a fixed-fixed resonant beam structure with high isolation compared to previous designs operating at ~800 nW of power comprised of piezoelectric aluminum nitride (AlN) and magnetostrictive (Co1-xFex)-based thin films that are less susceptible to vibration while providing similar characteristics to ME-MEMS cantilever devices. In this new design of double-clamped magnetoelectric MEMS resonators, we have also utilized thin films of a new iron-cobalt-hafnium alloy (Fe0.5Co0.5)0.92Hf0.08 that provides a low-stress, high magnetostrictive material with an amorphous crystalline structure and ultra-low magnetocrystalline anisotropy. Together, the improvements of this sensor design yield a magnetic field sensitivity of 125 Hz/mT when released in a compressive state. The overall detection limit of these sensors using an electric field drive and readout are presented, and noise sources are discussed. Based on these results, design parameters for future ME MEMS field sensors are discussed.

19.
Nano Lett ; 22(18): 7690-7698, 2022 09 28.
Artículo en Inglés | MEDLINE | ID: mdl-36121208

RESUMEN

The deluge of sensors and data generating devices has driven a paradigm shift in modern computing from arithmetic-logic centric to data-centric processing. Data-centric processing require innovations at the device level to enable novel compute-in-memory (CIM) operations. A key challenge in the construction of CIM architectures is the conflicting trade-off between the performance and their flexibility for various essential data operations. Here, we present a transistor-free CIM architecture that permits storage, search, and neural network operations on sub-50 nm thick Aluminum Scandium Nitride ferroelectric diodes (FeDs). Our circuit designs and devices can be directly integrated on top of Silicon microprocessors in a scalable process. By leveraging the field-programmability, nonvolatility, and nonlinearity of FeDs, search operations are demonstrated with a cell footprint <0.12 µm2 when projected onto 45 nm node technology. We further demonstrate neural network operations with 4-bit operation using FeDs. Our results highlight FeDs as candidates for efficient and multifunctional CIM platforms.


Asunto(s)
Escandio , Silicio , Aluminio , Lógica , Redes Neurales de la Computación
20.
Neuromodulation ; 26(4): 728-737, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-36759231

RESUMEN

BACKGROUND: Transcranial alternating current stimulation (tACS)-a noninvasive brain stimulation technique that modulates cortical oscillations in the brain-has shown the capacity to enhance working memory (WM) abilities in healthy individuals. The efficacy of tACS in the improvement of WM performance in healthy individuals is not yet fully understood. OBJECTIVE/HYPOTHESIS: This meta-analysis aimed to systematically evaluate the efficacy of tACS in the enhancement of WM in healthy individuals and to assess moderators of response to stimulation. We hypothesized that active tACS would significantly enhance WM compared with sham. We further hypothesized that it would do so in a task-dependent manner and that differing stimulation parameters would affect response to tACS. MATERIALS AND METHODS: Ten tACS studies met the inclusion criteria and provided 32 effects in the overall analysis. Random-effect models assessed mean change scores on WM tasks from baseline to poststimulation. The included studies involved varied in stimulation parameters, between-subject and within-subject study designs, and online vs offline tACS. RESULTS: We observed a significant, heterogeneous, and moderate effect size for active tACS in the enhancement of WM performance over sham (Cohen's d = 0.5). Cognitive load, task domain, session number, and stimulation region showed a significant relationship between active tACS and enhanced WM behavior over sham. CONCLUSIONS: Our findings indicate that active tACS enhances WM performance in healthy individuals compared with sham. Future randomized controlled trials are needed to further explore key parameters, including personalized stimulation vs standardized electroencephalography frequencies and maintenance of tACS effects, and whether tACS-induced effects translate to populations with WM impairments.


Asunto(s)
Memoria a Corto Plazo , Estimulación Transcraneal de Corriente Directa , Adulto , Humanos , Memoria a Corto Plazo/fisiología , Estimulación Transcraneal de Corriente Directa/métodos , Cognición/fisiología , Encéfalo , Electroencefalografía
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