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1.
Biomed Hub ; 9(1): 38-44, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38601364

RESUMO

At the Stanford-UCB Rare Disease Digital Health Symposium held in Stanford, California, on September 8, 2023, researchers, clinicians, payers, thought leaders, and rare disease caregivers and advocates discussed the current state of care delivery and future perspectives of digitally-enabled care for rare disease patient populations. Digital health aims to improve healthcare delivery through novel ways of providing access to more precise diagnosis, monitoring of disease progression, treatment, prognosis, and care management for rare disease patients. The meeting focused on highlighting challenges and unmet needs, data infrastructure and analytics, the need for targeted and effective personalized therapies, and the importance of digital care transformation. The meeting also covered the social and ethical impact of access to digitally delivered, patient-centered care, as well as views on implementation and patient autonomy and empowerment.

2.
Front Neurol ; 14: 1144183, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37588667

RESUMO

Introduction: We conducted a 3-month, prospective study in a population of patients with Myasthenia Gravis (MG), utilizing a fully decentralized approach for recruitment and monitoring (ClinicalTrials.gov Identifier: NCT04590716). The study objectives were to assess the feasibility of collecting real-world data through a smartphone-based research platform, in order to characterize symptom involvement during MG exacerbations. Methods: Primary data collection included daily electronically recorded patient-reported outcomes (ePROs) on the presence of MG symptoms, the level of symptom severity (using the MG-Activities of Daily Living assessment, MG-ADL), and exacerbation status. Participants were also given the option to contribute data on their physical activity levels from their own wearable devices. Results: The study enrolled and onboarded 113 participants across 37 US states, and 73% (N= 82) completed the study. The mean age of participants was 53.6 years, 60% were female. Participants were representative of a moderate to severe MG phenotype, with frequent exacerbations, high symptom burden and multiple comorbidities. 55% of participants (N=45) reported MG exacerbations during the study, with an average of 6.3 exacerbation days per participant. Median average MG-ADL scores for participants during self-reported exacerbation and non-exacerbation periods were 7 (interquartile range 4-9, range 1-19) and 0.3 (interquartile range 0-0.8, range 0-9), respectively. Analyses examining relationships between patient-reported and patient-generated health data streams and exacerbation status demonstrated concordance between self-reported MG-ADL scores and exacerbation status, and identified features that may be used to understand and predict the onset of MG symptom exacerbations, including: 1.) dynamic changes in day-to-day symptom reporting and severity 2.) daily step counts as a measure of physical activity and 3.) clinical characteristics of the patient, including the amount of time since their initial diagnosis and their active medications related to MG treatment. Finally, application of unsupervised machine learning methods identified unique clusters of exacerbation subtypes, each with their own specific representation of symptoms and symptom severity. Conclusion: While these symptom signatures require further study and validation, our results suggest that digital phenotyping, characterized by increased multidimensionality and frequency of the data collection, holds promise for furthering our understanding of clinically significant exacerbations and reimagining the approach to treating MG as a heterogeneous condition.

3.
Digit Biomark ; 7(1): 63-73, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37545566

RESUMO

Introduction: Myasthenia gravis (MG) is a rare autoimmune disease characterized by muscle weakness and fatigue. Ptosis (eyelid drooping) occurs due to fatigue of the muscles for eyelid elevation and is one symptom widely used by patients and healthcare providers to track progression of the disease. Margin reflex distance 1 (MRD1) is an accepted clinical measure of ptosis and is typically assessed using a hand-held ruler. In this work, we develop an AI model that enables automated measurement of MRD1 in self-recorded video clips collected using patient smartphones. Methods: A 3-month prospective observational study collected a dataset of video clips from patients with MG. Study participants were asked to perform an eyelid fatigability exercise to elicit ptosis while filming "selfie" videos on their smartphones. These images were collected in nonclinical settings, with no in-person training. The dataset was annotated by non-clinicians for (1) eye landmarks to establish ground truth MRD1 and (2) the quality of the video frames. The ground truth MRD1 (in millimeters, mm) was calculated from eye landmark annotations in the video frames using a standard conversion factor, the horizontal visible iris diameter of the human eye. To develop the model, we trained a neural network for eye landmark detection consisting of a ResNet50 backbone plus two dense layers of 78 dimensions on publicly available datasets. Only the ResNet50 backbone was used, discarding the last two layers. The embeddings from the ResNet50 were used as features for a support vector regressor (SVR) using a linear kernel, for regression to MRD1, in mm. The SVR was trained on data collected remotely from MG patients in the prospective study, split into training and development folds. The model's performance for MRD1 estimation was evaluated on a separate test fold from the study dataset. Results: On the full test fold (N = 664 images), the correlation between the ground truth and predicted MRD1 values was strong (r = 0.732). The mean absolute error was 0.822 mm; the mean of differences was -0.256 mm; and 95% limits of agreement (LOA) were -0.214-1.768 mm. Model performance showed no improvement when test data were gated to exclude "poor" quality images. Conclusions: On data generated under highly challenging real-world conditions from a variety of different smartphone devices, the model predicts MRD1 with a strong correlation (r = 0.732) between ground truth and predicted MRD1.

4.
PLoS One ; 18(6): e0287294, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37347755

RESUMO

Hemocyanins are multimeric oxygen transport proteins present in the blood of arthropods and molluscs, containing up to 8 oxygen-binding functional units per monomer. In molluscs, hemocyanins are assembled in decamer 'building blocks' formed of 5 dimer 'plates', routinely forming didecamer or higher-order assemblies with d5 or c5 symmetry. Here we describe the cryoEM structures of the didecamer (20-mer) and tridecamer (30-mer) forms of a novel hemocyanin from the slipper limpet Crepidula fornicata (SLH) at 7.0 and 4.7 Å resolution respectively. We show that two decamers assemble in a 'tail-tail' configuration, forming a partially capped cylinder, with an additional decamer adding on in 'head-tail' configuration to make the tridecamer. Analysis of SLH samples shows substantial heterogeneity, suggesting the presence of many higher-order multimers including tetra- and pentadecamers, formed by successive addition of decamers in head-tail configuration. Retrieval of sequence data for a full-length isoform of SLH enabled the use of Alphafold to produce a molecular model of SLH, which indicated the formation of dimer slabs with high similarity to those found in keyhole limpet hemocyanin. The fit of the molecular model to the cryoEM density was excellent, showing an overall structure where the final two functional units of the subunit (FU-g and FU-h) form the partial cap at one end of the decamer, and permitting analysis of the subunit interfaces governing the assembly of tail-tail and head-tail decamer interactions as well as potential sites for N-glycosylation. Our work contributes to the understanding of higher-order oligomer formation in molluscan hemocyanins and demonstrates the utility of Alphafold for building accurate structural models of large oligomeric proteins.


Assuntos
Artrópodes , Gastrópodes , Animais , Hemocianinas/metabolismo , Microscopia Crioeletrônica , Moluscos/química , Modelos Moleculares , Artrópodes/metabolismo , Gastrópodes/metabolismo , Polímeros
5.
Am J Bot ; 110(6): e16156, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36934437

RESUMO

PREMISE: Animal pollinators play an important role in pollen dispersal. Here, we assessed differences in pollen and seed dispersal and the role of pollinator functional groups with different foraging behaviors in generating patterns of genetic diversity over similar geographic ranges for two closely related taxa. We focused on two members of Oenothera section Calylophus (Onagraceae) that co-occur on gypsum outcrops throughout the northern Chihuahuan Desert but differ in floral phenotype and primary pollinator: Oenothera gayleana (bee) and O. hartwegii subsp. filifolia (hawkmoth). METHODS: We measured breeding system and floral traits and studied gene flow and population differentiation at the local (<13 km; four populations) and landscape (60-440 km; five populations) scales using 10-11 nuclear (pollen dispersal) and three plastid (seed dispersal) microsatellite markers. RESULTS: Both taxa were self-incompatible and floral traits were consistent with expectations for different pollinators. Seed and pollen dispersal patterns were distinctly different for both species. We found no evidence of genetic structure at the local scale but did at the landscape scale; O. gayleana showed greater differentiation and significant isolation by distance than in O. hartwegii subsp. filifolia. The plastid data were consistent with gravity dispersal of seeds and suggest that pollen dispersal is the principal driver of genetic structure in both species. CONCLUSIONS: We demonstrated that pollinator functional groups can impact genetic differentiation in different and predictable ways. Hawkmoths, with larger foraging distances, can maintain gene flow across greater spatial scales than bees.


Assuntos
Mariposas , Oenothera , Onagraceae , Abelhas/genética , Animais , Polinização , Melhoramento Vegetal , Pólen/genética , Flores
6.
Ann Rheum Dis ; 81(10): 1428-1437, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35710306

RESUMO

OBJECTIVES: Lupus T cells demonstrate aberrant DNA methylation patterns dominated by hypomethylation of interferon-regulated genes. The objective of this study was to identify additional lupus-associated DNA methylation changes and determine the genetic contribution to epigenetic changes characteristic of lupus. METHODS: Genome-wide DNA methylation was assessed in naïve CD4+ T cells from 74 patients with lupus and 74 age-matched, sex-matched and race-matched healthy controls. We applied a trend deviation analysis approach, comparing methylation data in our cohort with over 16 500 samples. Methylation quantitative trait loci (meQTL) analysis was performed by integrating methylation profiles with genome-wide genotyping data. RESULTS: In addition to the previously reported epigenetic signature in interferon-regulated genes, we observed hypomethylation in the promoter region of the miR-17-92 cluster in patients with lupus. Members of this microRNA cluster play an important role in regulating T cell proliferation and differentiation. Expression of two microRNAs in this cluster, miR-19b1 and miR-18a, showed a significant positive correlation with lupus disease activity. Among miR-18a target genes, TNFAIP3, which encodes a negative regulator of nuclear factor kappa B, was downregulated in lupus CD4+ T cells. MeQTL identified in lupus patients showed overlap with genetic risk loci for lupus, including CFB and IRF7. The lupus risk allele in IRF7 (rs1131665) was associated with significant IRF7 hypomethylation. However, <1% of differentially methylated CpG sites in patients with lupus were associated with an meQTL, suggesting minimal genetic contribution to lupus-associated epigenotypes. CONCLUSION: The lupus defining epigenetic signature, characterised by robust hypomethylation of interferon-regulated genes, does not appear to be determined by genetic factors. Hypomethylation of the miR-17-92 cluster that plays an important role in T cell activation is a novel epigenetic locus for lupus.


Assuntos
Lúpus Eritematoso Sistêmico , MicroRNAs , Linfócitos T , Linfócitos T CD4-Positivos/metabolismo , Metilação de DNA/genética , Epigênese Genética/genética , Epigenômica , Humanos , Interferons/genética , Lúpus Eritematoso Sistêmico/genética , Lúpus Eritematoso Sistêmico/metabolismo , MicroRNAs/genética , MicroRNAs/metabolismo
7.
BMC Health Serv Res ; 21(1): 675, 2021 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-34243772

RESUMO

BACKGROUND: Quantitative evidence suggests that interventions involving telephone calls and text message are feasible and effective for improving lifestyle intervention adherence and clinical outcomes among adults with obesity. The aim of this article is to provide qualitative insight into the perspectives and experiences of participants who completed a telehealth trial exploring the use of telephone and text support as adjunctive tools to support a community-based obesity management program. METHODS: Focus groups were conducted in order to evaluate program acceptability and overall participant perceptions of the clinical trial. Thematic content analysis was used to analyse the data, aided by the development of a thematic network. RESULTS: The telehealth trial was well received. Participants found the telephone and text message support highly beneficial, providing encouragement, motivation and accountability via a simple and convenient mode of communication. CONCLUSIONS: These findings suggest a high degree of promise for the incorporation of telephone and text support in obesity management.


Assuntos
Manejo da Obesidade , Telemedicina , Envio de Mensagens de Texto , Adulto , Humanos , Obesidade/prevenção & controle , Telefone
8.
Neurochem Int ; 147: 105039, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33915225

RESUMO

Epigenetic regulation plays an important role in controlling gene expression during complex processes, such as development of the human brain. Mutations in genes encoding chromatin modifying proteins and in the non-protein coding sequences of the genome can potentially alter transcription factor binding or chromatin accessibility. Such mutations can frequently cause neurodevelopmental disorders, therefore understanding how epigenetic regulation shapes brain development is of particular interest. While epigenetic regulation of neural development has been extensively studied in murine models, significant species-specific differences in both the genome sequence and in brain development necessitate human models. However, access to human fetal material is limited and these tissues cannot be grown or experimentally manipulated ex vivo. Therefore, models that recapitulate particular aspects of human fetal brain development, such as the in vitro differentiation of human pluripotent stem cells (hPSCs), are instrumental for studying the epigenetic regulation of human neural development. Here, we examine recent studies that have defined changes in the epigenomic landscape during fetal brain development. We compare these studies with analogous data derived by in vitro differentiation of hPSCs into specific neuronal cell types or as three-dimensional cerebral organoids. Such comparisons can be informative regarding which aspects of fetal brain development are faithfully recapitulated by in vitro differentiation models and provide a foundation for using experimentally tractable in vitro models of human brain development to study neural gene regulation and the basis of its disruption to cause neurodevelopmental disorders.


Assuntos
Encéfalo/metabolismo , Regulação da Expressão Gênica/fisiologia , Transtornos do Neurodesenvolvimento/metabolismo , Organoides/metabolismo , Animais , Humanos , Neurônios/metabolismo , Células-Tronco Pluripotentes/metabolismo
9.
JCI Insight ; 5(22)2020 11 19.
Artigo em Inglês | MEDLINE | ID: mdl-33108347

RESUMO

Epigenetic dysregulation is implicated in the pathogenesis of lupus. We performed a longitudinal analysis to assess changes in DNA methylation in lupus neutrophils over 4 years of follow-up and across disease activity levels using 229 patient samples. We demonstrate that DNA methylation profiles in lupus are partly determined by ancestry-associated genetic variations and are highly stable over time. DNA methylation levels in 2 CpG sites correlated significantly with changes in lupus disease activity. Progressive demethylation in SNX18 was observed with increasing disease activity in African American patients. Importantly, demethylation of a CpG site located within GALNT18 was associated with the development of active lupus nephritis. Differentially methylated genes between African American and European American lupus patients include type I IFN-response genes such as IRF7 and IFI44, and genes related to the NF-κB pathway. TREML4, which plays a vital role in TLR signaling, was hypomethylated in African American patients and demonstrated a strong cis-methylation quantitative trait loci (cis-meQTL) effect among 8855 cis-meQTL associations identified in our study.


Assuntos
Biomarcadores/análise , Negro ou Afro-Americano/genética , Metilação de DNA , Epigênese Genética , Nefrite Lúpica/patologia , Locos de Características Quantitativas , Adolescente , Adulto , Idoso , Estudos de Casos e Controles , Feminino , Estudo de Associação Genômica Ampla , Humanos , Fator Regulador 7 de Interferon/genética , Estudos Longitudinais , Nefrite Lúpica/genética , Pessoa de Meia-Idade , Prognóstico , Receptores Imunológicos/genética , Transdução de Sinais , Nexinas de Classificação/genética , População Branca/genética , Adulto Jovem
10.
Dev Biol ; 464(1): 11-23, 2020 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-32450229

RESUMO

Development of the complex structure of the vertebrate limb requires carefully orchestrated interactions between multiple regulatory pathways and proteins. Among these, precise regulation of 5' Hox transcription factor expression is essential for proper limb bud patterning and elaboration of distinct limb skeletal elements. Here, we identified Geminin (Gmnn) as a novel regulator of this process. A conditional model of Gmnn deficiency resulted in loss or severe reduction of forelimb skeletal elements, while both the forelimb autopod and hindlimb were unaffected. 5' Hox gene expression expanded into more proximal and anterior regions of the embryonic forelimb buds in this Gmnn-deficient model. A second conditional model of Gmnn deficiency instead caused a similar but less severe reduction of hindlimb skeletal elements and hindlimb polydactyly, while not affecting the forelimb. An ectopic posterior SHH signaling center was evident in the anterior hindlimb bud of Gmnn-deficient embryos in this model. This center ectopically expressed Hoxd13, the HOXD13 target Shh, and the SHH target Ptch1, while these mutant hindlimb buds also had reduced levels of the cleaved, repressor form of GLI3, a SHH pathway antagonist. Together, this work delineates a new role for Gmnn in modulating Hox expression to pattern the vertebrate limb.


Assuntos
Embrião de Mamíferos/embriologia , Geminina/metabolismo , Regulação da Expressão Gênica no Desenvolvimento , Membro Posterior/embriologia , Proteínas de Homeodomínio/metabolismo , Fatores de Transcrição/metabolismo , Animais , Embrião de Mamíferos/citologia , Geminina/genética , Proteínas Hedgehog/genética , Proteínas Hedgehog/metabolismo , Membro Posterior/citologia , Proteínas de Homeodomínio/genética , Camundongos , Camundongos Transgênicos , Receptor Patched-1/genética , Receptor Patched-1/metabolismo , Fatores de Transcrição/genética
11.
Infect Dis Ther ; 9(1): 175-183, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32062851

RESUMO

BACKGROUND: Candida species are responsible for 15% of bloodstream infections, leading to prolonged hospitalizations and increased mortality. With the rise in obesity, antifungal dosing is unclear. The purpose of this study was to determine differences in clinical outcomes between obese versus non-obese patients with Candida bloodstream infections. METHODS: This retrospective cohort included adult patient's first episode of Candida bloodstream infection treated with ≥ 48 h of antifungal therapy between 1 June 2013 and 31 August 2019. Patients were excluded for: dual systemic antifungal therapy, polymicrobial infections, or chronic candidiasis. The primary outcome was infection-related length of stay. Secondary outcomes included: time to candidemia resolution, 30-day readmission rates, and in-hospital mortality. RESULTS: Eighty patients were included (28 obese; 52 non-obese). Most were male (55%); median age was 54 years. Median BMI and weight were 36.3 kg/m2 and 103 kg versus 20.4 kg/m2 and 61 kg, respectively (p < 0.01). Baseline characteristics were comparable. C. albicans was isolated in 37.5% of cultures and C. glabrata in 30%. Micafungin was utilized empirically in 72.5% of patients; obese patients received definitive micafungin more frequently (57.1% vs. 21.2%; p < 0.01) and were treated longer (13 versus 10 days; p = 0.04). Infection-related length of stay was 19 days in the obese patients and 13 days in the non-obese patients (p = 0.05). Non-obese patients had a shorter duration of candidemia (5 versus 6 days; p = 0.02). In-hospital mortality was numerically higher in obese patients (21.4% versus 13.5%; p = 0.36). There were no differences in 30-day readmissions between groups. CONCLUSIONS: Worse clinical outcomes were observed for obese versus non-obese patients. Further clinical research is warranted.

12.
Viruses ; 11(12)2019 12 13.
Artigo em Inglês | MEDLINE | ID: mdl-31847268

RESUMO

Feline panleukopenia (FPL), a frequently fatal disease of cats, is caused by feline parvovirus (FPV) or canine parvovirus (CPV). We investigated simultaneous outbreaks of FPL between 2014 and 2018 in Australia, New Zealand and the United Arab Emirates (UAE) where FPL outbreaks had not been reported for several decades. Case data from 989 cats and clinical samples from additional 113 cats were obtained to determine the cause of the outbreaks and epidemiological factors involved. Most cats with FPL were shelter-housed, 9 to 10 weeks old at diagnosis, unvaccinated, had not completed a primary vaccination series or had received vaccinations noncompliant with current guidelines. Analysis of parvoviral VP2 sequence data confirmed that all FPL cases were caused by FPV and not CPV. Phylogenetic analysis revealed that each of these outbreaks was caused by a distinct FPV, with two virus lineages present in eastern Australia and virus movement between different geographical locations. Viruses from the UAE outbreak formed a lineage of unknown origin. FPV vaccine virus was detected in the New Zealand cases, highlighting the difficulty of distinguishing the co-incidental shedding of vaccine virus in vaccinated cats. Inadequate vaccination coverage in shelter-housed cats was a common factor in all outbreaks, likely precipitating the multiple re-emergence of infection events.


Assuntos
Surtos de Doenças , Vírus da Panleucopenia Felina/classificação , Panleucopenia Felina/epidemiologia , Panleucopenia Felina/virologia , Animais , Austrália/epidemiologia , Gatos , DNA Viral , Geografia Médica , Nova Zelândia/epidemiologia , Estudos Retrospectivos , Análise de Sequência de DNA , Emirados Árabes Unidos/epidemiologia , Carga Viral
13.
Int J Behav Med ; 26(6): 580-590, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31512155

RESUMO

BACKGROUND: Behavioral treatment strategies improve adherence to lifestyle intervention for adults with obesity, but can be time and resource intensive when delivered via traditional face-to-face care. This study aimed to investigate the efficacy and optimal timing of using telephone calls and text message as adjunctive tools to support a community-based obesity management program. METHOD: This 8-month randomized controlled crossover trial recruited 61 adults with class III obesity (BMI > 40 kg/m2) enrolled in a publicly funded obesity management service (OMS). Participants were randomly assigned to receive telephone and text message support in addition to standard OMS care, or standard OMS care alone. After 4 months, participants crossed over to the alternative sequence. The technological support was based on self-determination theory. Outcome measures included diet, physical activity, anthropometry, self-efficacy, and treatment self-regulation. RESULTS: Telephone and text message support improved lifestyle intervention adherence and clinical outcomes when compared with standard care. Participants who received the intervention in the first 4-month period lost 4.87 kg, compared with no weight loss (+ 0.38 kg) in the standard care only group. There was no evidence to indicate an optimal timing of the intervention, with both groups achieving significant results by the end of the intervention. CONCLUSION: These results suggest a high degree of promise for the incorporation of telephone and text message support into community-based obesity management services. The findings have the potential to improve existing practices and reduce the burden on the health care system by demonstrating a resource-effective improvement to obesity management service delivery.


Assuntos
Terapia Comportamental/métodos , Manejo da Obesidade/métodos , Obesidade/terapia , Cooperação do Paciente/psicologia , Telemedicina/métodos , Adulto , Estudos Cross-Over , Dieta/psicologia , Exercício Físico/psicologia , Feminino , Humanos , Estilo de Vida , Masculino , Pessoa de Meia-Idade , Obesidade/psicologia , Autocuidado/psicologia , Telefone , Envio de Mensagens de Texto , Resultado do Tratamento , Redução de Peso
14.
Mol Autism ; 10: 51, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31893020

RESUMO

Background: Autism spectrum disorder (ASD) is a neurodevelopmental disorder with pronounced heritability in the general population. This is largely attributable to the effects of polygenic susceptibility, with inherited liability exhibiting distinct sex differences in phenotypic expression. Attempts to model ASD in human cellular systems have principally involved rare de novo mutations associated with ASD phenocopies. However, by definition, these models are not representative of polygenic liability, which accounts for the vast share of population-attributable risk. Methods: Here, we performed what is, to our knowledge, the first attempt to model multiplex autism using patient-derived induced pluripotent stem cells (iPSCs) in a family manifesting incremental degrees of phenotypic expression of inherited liability (absent, intermediate, severe). The family members share an inherited variant of uncertain significance (VUS) in GPD2, a gene that was previously associated with developmental disability but here is insufficient by itself to cause ASD. iPSCs from three first-degree relatives and an unrelated control were differentiated into both cortical excitatory (cExN) and cortical inhibitory (cIN) neurons, and cellular phenotyping and transcriptomic analysis were conducted. Results: cExN neurospheres from the two affected individuals were reduced in size, compared to those derived from unaffected related and unrelated individuals. This reduction was, at least in part, due to increased apoptosis of cells from affected individuals upon initiation of cExN neural induction. Likewise, cIN neural progenitor cells from affected individuals exhibited increased apoptosis, compared to both unaffected individuals. Transcriptomic analysis of both cExN and cIN neural progenitor cells revealed distinct molecular signatures associated with affectation, including the misregulation of suites of genes associated with neural development, neuronal function, and behavior, as well as altered expression of ASD risk-associated genes. Conclusions: We have provided evidence of morphological, physiological, and transcriptomic signatures of polygenic liability to ASD from an analysis of cellular models derived from a multiplex autism family. ASD is commonly inherited on the basis of additive genetic liability. Therefore, identifying convergent cellular and molecular phenotypes resulting from polygenic and monogenic susceptibility may provide a critical bridge for determining which of the disparate effects of rare highly deleterious mutations might also apply to common autistic syndromes.


Assuntos
Transtorno Autístico/patologia , Comunicação Celular , Células-Tronco Pluripotentes Induzidas/patologia , Neurônios/patologia , Adolescente , Transtorno Autístico/genética , Diferenciação Celular/genética , Pré-Escolar , Análise por Conglomerados , Família , Feminino , Regulação da Expressão Gênica , Genótipo , Humanos , Lactente , Recém-Nascido , Interneurônios/patologia , Masculino , Modelos Biológicos , Células-Tronco Neurais/metabolismo , Linhagem , Fenótipo , Gravidez , Reprodutibilidade dos Testes , Transcriptoma/genética
15.
J Chem Phys ; 149(3): 034703, 2018 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-30037261

RESUMO

The delicate balance between hydrogen bonding and van der Waals interactions determines the stability, structure, and chirality of many molecular and supramolecular aggregates weakly adsorbed on solid surfaces. Yet the inherent complexity of these systems makes their experimental study at the molecular level very challenging. In this quest, small alcohols adsorbed on metal surfaces have become a useful model system to gain fundamental insight into the interplay of such molecule-surface and molecule-molecule interactions. Here, through a combination of scanning tunneling microscopy and density functional theory, we compare and contrast the adsorption and self-assembly of a range of small alcohols from methanol to butanol on Au(111). We find that longer chained alcohols prefer to form zigzag chains held together by extended hydrogen bonded networks between adjacent molecules. When alcohols bind to a metal surface datively via one of the two lone electron pairs of the oxygen atom, they become chiral. Therefore, the chain structures are formed by a hydrogen-bonded network between adjacent molecules with alternating adsorbed chirality. These chain structures accommodate longer alkyl tails through larger unit cells, while the position of the hydroxyl group within the alcohol molecule can produce denser unit cells that maximize intermolecular interactions. Interestingly, when intrinsic chirality is introduced into the molecule as in the case of 2-butanol, the assembly changes completely and square packing structures with chiral pockets are observed. This is rationalized by the fact that the intrinsic chirality of the molecule directs the chirality of the adsorbed hydroxyl group meaning that heterochiral chain structures cannot form. Overall this study provides a general framework for understanding the effect of simple alcohol molecular adstructures on hydrogen bonded aggregates and paves the way for rationalizing 2D chiral supramolecular assembly.

16.
Proteomics ; 18(14): e1700462, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29687599

RESUMO

A 3D cell culture is an artificially created environment in which cells are permitted to grow/interact with their surroundings in all three dimensions. Derived from 3D cell culture, organoids are generally small-scale constructs of cells that are fabricated in the laboratory to serve as 3D representations of in vivo tissues and organs. Due to regulatory, economic and societal issues concerning the use of animals in scientific research, it seems clear that the use of 3D cell culture and organoids in for example early stage studies of drug efficacy and toxicity will increase. The combination of such 3D tissue models with mass spectrometry imaging provides a label-free methodology for the study of drug absorption/penetration, drug efficacy/toxicity, and drug biotransformation. In this article, some of the successes achieved to date and challenges to be overcome before this methodology is more widely adopted are discussed.


Assuntos
Descoberta de Drogas/métodos , Processamento de Imagem Assistida por Computador/métodos , Imageamento Tridimensional/métodos , Espectrometria de Massas/métodos , Organoides/metabolismo , Esferoides Celulares/metabolismo , Técnicas de Cultura de Tecidos/métodos , Animais , Humanos , Modelos Biológicos , Organoides/citologia , Organoides/efeitos dos fármacos , Esferoides Celulares/citologia , Esferoides Celulares/efeitos dos fármacos
17.
Epigenomics ; 10(2): 219-231, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29334242

RESUMO

Human neurodevelopmental disorders (NDDs) involve mutations in hundreds of individual genes, with over-representation in genes encoding proteins that alter chromatin structure to modulate gene expression. Here, we highlight efforts to model these NDDs through in vitro differentiation of patient-specific induced pluripotent stem cells into neurons. We discuss how epigenetic regulation controls normal cortical development, how mutations in several classes of epigenetic regulators contribute to NDDs, and approaches for modeling cortical development and function using both directed differentiation and formation of cerebral organoids. We explore successful applications of these models to study both syndromic and nonsyndromic NDDs and to define convergent mechanisms, addressing both the potential and challenges of using this approach to define cellular and molecular mechanisms that underlie NDDs.


Assuntos
Montagem e Desmontagem da Cromatina , Metilação de DNA , Epigênese Genética , Código das Histonas , Células-Tronco Pluripotentes Induzidas , Transtornos do Neurodesenvolvimento/genética , Transtorno Autístico/genética , Humanos , Modelos Neurológicos , Modelos Teóricos , Mutação , Telencéfalo
18.
Q J Exp Psychol (Hove) ; 71(6): 1300-1311, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28415903

RESUMO

Recent literature has revealed underestimation effects in numerical judgments when adult participants are presented with emotional stimuli (as opposed to neutral). Whether these numerical biases emerge early in development however, or instead reflect overt, learned responses to emotional stimuli across development are unclear. Moreover, reported links between numerical acuity and mathematics achievement point to the importance of exploring how numerical approximation abilities in childhood may be influenced in real-world affective contexts. In this study, children (aged 6-10 years) and adults were presented with happy and neutral facial stimuli in the context of a numerical bisection task. Results reveal that children, like adults, underestimate number following emotional (i.e., happy) faces (relative to neutral). However, children's, but not adult's, responses were also significantly more precise following emotional stimuli. In a second experiment, adult judgments revealed a similar increase in precision following emotional stimuli when numerical discriminations were more challenging (involving larger sets). Together, results are the first to reveal children, like adults, underestimate number in the context of emotional stimuli and this underestimation bias is accompanied with enhanced response precision.


Assuntos
Envelhecimento/fisiologia , Emoções/fisiologia , Julgamento/fisiologia , Matemática , Reconhecimento Visual de Modelos/fisiologia , Adolescente , Adulto , Análise de Variância , Criança , Análise Discriminante , Expressão Facial , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estimulação Luminosa , Adulto Jovem
19.
J Autoimmun ; 86: 19-28, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-29066026

RESUMO

OBJECTIVE: The goal of this study was to comprehensively characterize CD4+CD28+ T cells overexpressing CD11a and KIR genes, and examine the relationship between this T cell subset, genetic risk, and disease activity in lupus. METHODS: The size of the CD4+CD28+KIR+CD11ahi T cell subset was determined by flow cytometry, and total genetic risk for lupus was calculated in 105 female patients using 43 confirmed genetic susceptibility loci. Primary CD4+CD28+KIR+CD11ahi T cells were isolated from lupus patients or were induced from healthy individuals using 5-azacytidine. Genome-wide DNA methylation was analyzed using an array-based approach, and the transcriptome was assessed by RNA sequencing. Transcripts in the CDR3 region were used to assess the TCR repertoire. Chromatin accessibility was determined using ATAC-seq. RESULTS: A total of 31,019 differentially methylated sites were identified in induced KIR+CD11ahi T cells with >99% being hypomethylated. RNA sequencing revealed a clear pro-inflammatory transcriptional profile. TCR repertoire analysis suggests less clonotype diversity in KIR+CD11ahi compared to autologous KIR-CD11alow T cells. Similarly, primary KIR+CD11ahi T cells isolated from lupus patients were hypomethylated and characterized by a pro-inflammatory chromatin structure. We show that the genetic risk for lupus was significantly higher in African-American compared to European-American lupus patients. The demethylated CD4+CD28+KIR+CD11ahi T cell subset size was a better predictor of disease activity in young (age ≤ 40) European-American patients independent of genetic risk. CONCLUSION: CD4+CD28+KIR+CD11ahi T cells are demethylated and characterized by pro-inflammatory epigenetic and transcriptional profiles in lupus. Eliminating these cells or blocking their pro-inflammatory characteristics might present a novel therapeutic approach for lupus.


Assuntos
Negro ou Afro-Americano , Inflamação/imunologia , Lúpus Eritematoso Sistêmico/imunologia , Subpopulações de Linfócitos T/imunologia , Linfócitos T/imunologia , Antígeno CD11a/metabolismo , Antígenos CD28/metabolismo , Antígenos CD4/metabolismo , Células Cultivadas , Metilação de DNA , Progressão da Doença , Epigênese Genética , Feminino , Perfil Genético , Humanos , Imunofenotipagem , Lúpus Eritematoso Sistêmico/diagnóstico , Lúpus Eritematoso Sistêmico/epidemiologia , Receptores KIR/metabolismo , Risco , Análise de Sequência de RNA , Estados Unidos/epidemiologia
20.
Genes Cancer ; 8(9-10): 725-744, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29234490

RESUMO

Medulloblastoma is the most common malignant brain cancer of childhood. Further understanding of tumorigenic mechanisms may define new therapeutic targets. Geminin maintains genome fidelity by controlling re-initiation of DNA replication within a cell cycle. In some contexts, Geminin inhibition induces cancer-selective cell cycle arrest and apoptosis and/or sensitizes cancer cells to Topoisomerase IIα inhibitors such as etoposide, which is used in combination chemotherapies for medulloblastoma. However, Geminin's potential role in medulloblastoma tumorigenesis remained undefined. Here, we found that Geminin is highly expressed in human and mouse medulloblastomas and in murine granule neuron precursor (GNP) cells during cerebellar development. Conditional Geminin loss significantly enhanced survival in the SmoA1 mouse medulloblastoma model. Geminin loss in this model also reduced numbers of preneoplastic GNPs persisting at one postnatal month, while at two postnatal weeks these cells exhibited an elevated DNA damage response and apoptosis. Geminin knockdown likewise impaired human medulloblastoma cell growth, activating G2 checkpoint and DNA damage response pathways, triggering spontaneous apoptosis, and enhancing G2 accumulation of cells in response to etoposide treatment. Together, these data suggest preneoplastic and cancer cell-selective roles for Geminin in medulloblastoma, and suggest that targeting Geminin may impair tumor growth and enhance responsiveness to Topoisomerase IIα-directed chemotherapies.

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