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1.
Mol Cell ; 79(1): 84-98.e9, 2020 07 02.
Artigo em Inglês | MEDLINE | ID: mdl-32526163

RESUMO

Rett syndrome (RTT), mainly caused by mutations in methyl-CpG binding protein 2 (MeCP2), is one of the most prevalent intellectual disorders without effective therapies. Here, we used 2D and 3D human brain cultures to investigate MeCP2 function. We found that MeCP2 mutations cause severe abnormalities in human interneurons (INs). Surprisingly, treatment with a BET inhibitor, JQ1, rescued the molecular and functional phenotypes of MeCP2 mutant INs. We uncovered that abnormal increases in chromatin binding of BRD4 and enhancer-promoter interactions underlie the abnormal transcription in MeCP2 mutant INs, which were recovered to normal levels by JQ1. We revealed cell-type-specific transcriptome impairment in MeCP2 mutant region-specific human brain organoids that were rescued by JQ1. Finally, JQ1 ameliorated RTT-like phenotypes in mice. These data demonstrate that BRD4 dysregulation is a critical driver for RTT etiology and suggest that targeting BRD4 could be a potential therapeutic opportunity for RTT.


Assuntos
Azepinas/farmacologia , Encéfalo/patologia , Proteínas de Ciclo Celular/metabolismo , Interneurônios/patologia , Proteína 2 de Ligação a Metil-CpG/fisiologia , Síndrome de Rett/patologia , Fatores de Transcrição/metabolismo , Transcriptoma/efeitos dos fármacos , Triazóis/farmacologia , Animais , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Proteínas de Ciclo Celular/genética , Feminino , Células-Tronco Embrionárias Humanas/efeitos dos fármacos , Células-Tronco Embrionárias Humanas/metabolismo , Células-Tronco Embrionárias Humanas/patologia , Humanos , Células-Tronco Pluripotentes Induzidas/efeitos dos fármacos , Células-Tronco Pluripotentes Induzidas/metabolismo , Células-Tronco Pluripotentes Induzidas/patologia , Interneurônios/efeitos dos fármacos , Interneurônios/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Mutação , Fenótipo , Síndrome de Rett/tratamento farmacológico , Síndrome de Rett/genética , Síndrome de Rett/metabolismo , Fatores de Transcrição/genética
2.
PLoS Biol ; 21(11): e3002373, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37939126

RESUMO

Corrective feedback received on perceptual decisions is crucial for adjusting decision-making strategies to improve future choices. However, its complex interaction with other decision components, such as previous stimuli and choices, challenges a principled account of how it shapes subsequent decisions. One popular approach, based on animal behavior and extended to human perceptual decision-making, employs "reinforcement learning," a principle proven successful in reward-based decision-making. The core idea behind this approach is that decision-makers, although engaged in a perceptual task, treat corrective feedback as rewards from which they learn choice values. Here, we explore an alternative idea, which is that humans consider corrective feedback on perceptual decisions as evidence of the actual state of the world rather than as rewards for their choices. By implementing these "feedback-as-reward" and "feedback-as-evidence" hypotheses on a shared learning platform, we show that the latter outperforms the former in explaining how corrective feedback adjusts the decision-making strategy along with past stimuli and choices. Our work suggests that humans learn about what has happened in their environment rather than the values of their own choices through corrective feedback during perceptual decision-making.


Assuntos
Comportamento de Escolha , Tomada de Decisões , Animais , Humanos , Retroalimentação , Recompensa , Reforço Psicológico
3.
Plant J ; 118(1): 106-123, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38111157

RESUMO

Sorghum anthracnose caused by the fungus Colletotrichum sublineola (Cs) is a damaging disease of the crop. Here, we describe the identification of ANTHRACNOSE RESISTANCE GENES (ARG4 and ARG5) encoding canonical nucleotide-binding leucine-rich repeat (NLR) receptors. ARG4 and ARG5 are dominant resistance genes identified in the sorghum lines SAP135 and P9830, respectively, that show broad-spectrum resistance to Cs. Independent genetic studies using populations generated by crossing SAP135 and P9830 with TAM428, fine mapping using molecular markers, comparative genomics and gene expression studies determined that ARG4 and ARG5 are resistance genes against Cs strains. Interestingly, ARG4 and ARG5 are both located within clusters of duplicate NLR genes at linked loci separated by ~1 Mb genomic region. SAP135 and P9830 each carry only one of the ARG genes while having the recessive allele at the second locus. Only two copies of the ARG5 candidate genes were present in the resistant P9830 line while five non-functional copies were identified in the susceptible line. The resistant parents and their recombinant inbred lines carrying either ARG4 or ARG5 are resistant to strains Csgl1 and Csgrg suggesting that these genes have overlapping specificities. The role of ARG4 and ARG5 in resistance was validated through sorghum lines carrying independent recessive alleles that show increased susceptibility. ARG4 and ARG5 are located within complex loci displaying interesting haplotype structures and copy number variation that may have resulted from duplication. Overall, the identification of anthracnose resistance genes with unique haplotype stucture provides a foundation for genetic studies and resistance breeding.


Assuntos
Colletotrichum , Sorghum , Haplótipos , Sorghum/genética , Variações do Número de Cópias de DNA , Melhoramento Vegetal , Genômica , Doenças das Plantas/genética , Doenças das Plantas/microbiologia , Colletotrichum/fisiologia , Resistência à Doença/genética
4.
Hum Mol Genet ; 32(4): 696-707, 2023 01 27.
Artigo em Inglês | MEDLINE | ID: mdl-36255742

RESUMO

BACKGROUND: Asthma is a heterogeneous common respiratory disease that remains poorly understood. The established genetic associations fail to explain the high estimated heritability, and the prevalence of asthma differs between populations and geographic regions. Robust association analyses incorporating different genetic ancestries and whole-genome sequencing data may identify novel genetic associations. METHODS: We performed family-based genome-wide association analyses of childhood-onset asthma based on whole-genome sequencing (WGS) data for the 'The Genetic Epidemiology of Asthma in Costa Rica' study (GACRS) and the Childhood Asthma Management Program (CAMP). Based on parent-child trios with children diagnosed with asthma, we performed a single variant analysis using an additive and a recessive genetic model and a region-based association analysis of low-frequency and rare variants. RESULTS: Based on 1180 asthmatic trios (894 GACRS trios and 286 CAMP trios, a total of 3540 samples with WGS data), we identified three novel genetic loci associated with childhood-onset asthma: rs4832738 on 4p14 ($P=1.72\ast{10}^{-9}$, recessive model), rs1581479 on 8p22 ($P=1.47\ast{10}^{-8}$, additive model) and rs73367537 on 10q26 ($P=1.21\ast{10}^{-8}$, additive model in GACRS only). Integrative analyses suggested potential novel candidate genes underlying these associations: PGM2 on 4p14 and FGF20 on 8p22. CONCLUSION: Our family-based whole-genome sequencing analysis identified three novel genetic loci for childhood-onset asthma. Gene expression data and integrative analyses point to PGM2 on 4p14 and FGF20 on 8p22 as linked genes. Furthermore, region-based analyses suggest independent potential low-frequency/rare variant associations on 8p22. Follow-up analyses are needed to understand the functional mechanisms and generalizability of these associations.


Assuntos
Asma , Estudo de Associação Genômica Ampla , Humanos , Predisposição Genética para Doença , Asma/genética , Loci Gênicos , Sequenciamento Completo do Genoma , Polimorfismo de Nucleotídeo Único/genética , Fatores de Crescimento de Fibroblastos/genética
5.
Brief Bioinform ; 24(1)2023 01 19.
Artigo em Inglês | MEDLINE | ID: mdl-36585781

RESUMO

Genetic similarity matrices are commonly used to assess population substructure (PS) in genetic studies. Through simulation studies and by the application to whole-genome sequencing (WGS) data, we evaluate the performance of three genetic similarity matrices: the unweighted and weighted Jaccard similarity matrices and the genetic relationship matrix. We describe different scenarios that can create numerical pitfalls and lead to incorrect conclusions in some instances. We consider scenarios in which PS is assessed based on loci that are located across the genome ('globally') and based on loci from a specific genomic region ('locally'). We also compare scenarios in which PS is evaluated based on loci from different minor allele frequency bins: common (>5%), low-frequency (5-0.5%) and rare (<0.5%) single-nucleotide variations (SNVs). Overall, we observe that all approaches provide the best clustering performance when computed based on rare SNVs. The performance of the similarity matrices is very similar for common and low-frequency variants, but for rare variants, the unweighted Jaccard matrix provides preferable clustering features. Based on visual inspection and in terms of standard clustering metrics, its clusters are the densest and the best separated in the principal component analysis of variants with rare SNVs compared with the other methods and different allele frequency cutoffs. In an application, we assessed the role of rare variants on local and global PS, using WGS data from multiethnic Alzheimer's disease data sets and European or East Asian populations from the 1000 Genome Project.


Assuntos
Genoma , Genômica , Análise de Componente Principal , Frequência do Gene , Simulação por Computador , Estudo de Associação Genômica Ampla , Polimorfismo de Nucleotídeo Único
6.
Plant Cell ; 34(5): 1641-1665, 2022 04 26.
Artigo em Inglês | MEDLINE | ID: mdl-35018449

RESUMO

Sorghum (Sorghum bicolor), the fifth most widely grown cereal crop globally, provides food security for millions of people. Anthracnose caused by the fungus Colletotrichum sublineola is a major disease of sorghum worldwide. We discovered a major fungal resistance locus in sorghum composed of the nucleotide-binding leucine-rich repeat receptor gene ANTHRACNOSE RESISTANCE GENE1 (ARG1) that is completely nested in an intron of a cis-natural antisense transcript (NAT) gene designated CARRIER OF ARG1 (CARG). Susceptible genotypes express CARG and two alternatively spliced ARG1 transcripts encoding truncated proteins lacking the leucine-rich repeat domains. In resistant genotypes, elevated expression of an intact allele of ARG1, attributed to the loss of CARG transcription and the presence of miniature inverted-repeat transposable element sequences, resulted in broad-spectrum resistance to fungal pathogens with distinct virulence strategies. Increased ARG1 expression in resistant genotypes is also associated with higher histone H3K4 and H3K36 methylation. In susceptible genotypes, lower ARG1 expression is associated with reduced H3K4 and H3K36 methylation and increased expression of NATs of CARG. The repressive chromatin state associated with H3K9me2 is low in CARG-expressing genotypes within the CARG exon and higher in genotypes with low CARG expression. Thus, ARG1 is regulated by multiple mechanisms and confers broad-spectrum, strong resistance to fungal pathogens.


Assuntos
Sorghum , Grão Comestível , Genótipo , Humanos , Leucina/genética , Doenças das Plantas/microbiologia , Sorghum/genética
7.
Proc Natl Acad Sci U S A ; 119(29): e2110746119, 2022 07 19.
Artigo em Inglês | MEDLINE | ID: mdl-35858361

RESUMO

Intraneuronal inclusions of misfolded α-synuclein (α-syn) and prion-like spread of the pathologic α-syn contribute to progressive neuronal death in Parkinson's disease (PD). Despite the pathologic significance, no efficient therapeutic intervention targeting α-synucleinopathy has been developed. In this study, we provide evidence that astrocytes, especially those cultured from the ventral midbrain (VM), show therapeutic potential to alleviate α-syn pathology in multiple in vitro and in vivo α-synucleinopathic models. Regulation of neuronal α-syn proteostasis underlies the therapeutic function of astrocytes. Specifically, VM-derived astrocytes inhibited neuronal α-syn aggregation and transmission in a paracrine manner by correcting not only intraneuronal oxidative and mitochondrial stresses but also extracellular inflammatory environments, in which α-syn proteins are prone to pathologic misfolding. The astrocyte-derived paracrine factors also promoted disassembly of extracellular α-syn aggregates. In addition to the aggregated form of α-syn, VM astrocytes reduced total α-syn protein loads both by actively scavenging extracellular α-syn fibrils and by a paracrine stimulation of neuronal autophagic clearance of α-syn. Transplantation of VM astrocytes into the midbrain of PD model mice alleviated α-syn pathology and protected the midbrain dopamine neurons from neurodegeneration. We further showed that cografting of VM astrocytes could be exploited in stem cell-based therapy for PD, in which host-to-graft transmission of α-syn pathology remains a critical concern for long-term cell therapeutic effects.


Assuntos
Astrócitos , Transplante de Tecido Encefálico , Doença de Parkinson , Proteostase , alfa-Sinucleína , Animais , Astrócitos/transplante , Modelos Animais de Doenças , Neurônios Dopaminérgicos/metabolismo , Mesencéfalo/patologia , Mesencéfalo/cirurgia , Camundongos , Doença de Parkinson/patologia , Doença de Parkinson/terapia , alfa-Sinucleína/metabolismo
8.
PLoS Genet ; 18(11): e1010464, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36383614

RESUMO

The identification and understanding of gene-environment interactions can provide insights into the pathways and mechanisms underlying complex diseases. However, testing for gene-environment interaction remains a challenge since a.) statistical power is often limited and b.) modeling of environmental effects is nontrivial and such model misspecifications can lead to false positive interaction findings. To address the lack of statistical power, recent methods aim to identify interactions on an aggregated level using, for example, polygenic risk scores. While this strategy can increase the power to detect interactions, identifying contributing genes and pathways is difficult based on these relatively global results. Here, we propose RITSS (Robust Interaction Testing using Sample Splitting), a gene-environment interaction testing framework for quantitative traits that is based on sample splitting and robust test statistics. RITSS can incorporate sets of genetic variants and/or multiple environmental factors. Based on the user's choice of statistical/machine learning approaches, a screening step selects and combines potential interactions into scores with improved interpretability. In the testing step, the application of robust statistics minimizes the susceptibility to main effect misspecifications. Using extensive simulation studies, we demonstrate that RITSS controls the type 1 error rate in a wide range of scenarios, and we show how the screening strategy influences statistical power. In an application to lung function phenotypes and human height in the UK Biobank, RITSS identified highly significant interactions based on subcomponents of genetic risk scores. While the contributing single variant interaction signals are weak, our results indicate interaction patterns that result in strong aggregated effects, providing potential insights into underlying gene-environment interaction mechanisms.


Assuntos
Modelos Genéticos , Polimorfismo de Nucleotídeo Único , Humanos , Loci Gênicos , Interação Gene-Ambiente , Fenótipo , Simulação por Computador , Estudo de Associação Genômica Ampla
9.
J Neurosci ; 43(25): 4664-4683, 2023 06 21.
Artigo em Inglês | MEDLINE | ID: mdl-37286349

RESUMO

Binary classification, an act of sorting items into two classes by setting a boundary, is biased by recent history. One common form of such bias is repulsive bias, a tendency to sort an item into the class opposite to its preceding items. Sensory-adaptation and boundary-updating are considered as two contending sources of the repulsive bias, yet no neural support has been provided for either source. Here, we explored human brains of both men and women, using functional magnetic resonance imaging (fMRI), to find such support by relating the brain signals of sensory-adaptation and boundary-updating to human classification behavior. We found that the stimulus-encoding signal in the early visual cortex adapted to previous stimuli, yet its adaptation-related changes were dissociated from current choices. Contrastingly, the boundary-representing signals in the inferior-parietal and superior-temporal cortices shifted to previous stimuli and covaried with current choices. Our exploration points to boundary-updating, rather than sensory-adaptation, as the origin of the repulsive bias in binary classification.SIGNIFICANCE STATEMENT Many animal and human studies on perceptual decision-making have reported an intriguing history effect called "repulsive bias," a tendency to classify an item as the opposite class of its previous item. Regarding the origin of repulsive bias, two contending ideas have been proposed: "bias in stimulus representation because of sensory adaptation" versus "bias in class-boundary setting because of belief updating." By conducting model-based neuroimaging experiments, we verified their predictions about which brain signal should contribute to the trial-to-trial variability in choice behavior. We found that the brain signal of class boundary, but not stimulus representation, contributed to the choice variability associated with repulsive bias. Our study provides the first neural evidence supporting the boundary-based hypothesis of repulsive bias.


Assuntos
Encéfalo , Tomada de Decisões , Masculino , Animais , Humanos , Feminino , Encéfalo/diagnóstico por imagem , Lobo Temporal , Percepção Visual
10.
Plant J ; 113(2): 308-326, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36441009

RESUMO

Sorghum is an important food and feed crop globally; its production is hampered by anthracnose disease caused by the fungal pathogen Colletotrichum sublineola (Cs). Here, we report identification and characterization of ANTHRACNOSE RESISTANCE GENE 2 (ARG2) encoding a nucleotide-binding leucine-rich repeat (NLR) protein that confers race-specific resistance to Cs strains. ARG2 is one of a cluster of several NLR genes initially identified in the sorghum differential line SC328C that is resistant to some Cs strains. This cluster shows structural and copy number variations in different sorghum genotypes. Different sorghum lines carrying independent ARG2 alleles provided the genetic validation for the identity of the ARG2 gene. ARG2 expression is induced by Cs, and chitin induces ARG2 expression in resistant but not in susceptible lines. ARG2-mediated resistance is accompanied by higher expression of defense and secondary metabolite genes at early stages of infection, and anthocyanin and zeatin metabolisms are upregulated in resistant plants. Interestingly, ARG2 localizes to the plasma membrane when transiently expressed in Nicotiana benthamiana. Importantly, ARG2 plants produced higher shoot dry matter than near-isogenic lines carrying the susceptible allele suggesting an absence of an ARG2 associated growth trade-off. Furthermore, ARG2-mediated resistance is stable at a wide range of temperatures. Our observations open avenues for resistance breeding and for dissecting mechanisms of resistance.


Assuntos
Colletotrichum , Sorghum , Sorghum/genética , Variações do Número de Cópias de DNA , Doenças das Plantas/genética , Doenças das Plantas/microbiologia , Melhoramento Vegetal , Genótipo , Resistência à Doença/genética
11.
Eur J Neurosci ; 59(6): 1311-1331, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38056070

RESUMO

Dissecting the diversity of midbrain dopamine (DA) neurons by optotagging is a promising addition to better identify their functional properties and contribution to motivated behavior. Retrograde molecular targeting of DA neurons with specific axonal projection allows further refinement of this approach. Here, we focus on adult mouse DA neurons in the substantia nigra pars compacta (SNc) projecting to dorsal striatum (DS) by demonstrating the selectivity of a floxed AAV9-based retrograde channelrhodopsin-eYFP (ChR-eYFP) labeling approach in DAT-cre mice. Furthermore, we show the utility of a sparse labeling version for anatomical single-cell reconstruction and demonstrate that ChR-eYFR expressing DA neurons retain intrinsic functional properties indistinguishable from conventionally retrogradely red-beads-labeled neurons. We systematically explore the properties of optogenetically evoked action potentials (oAPs) and their interaction with intrinsic pacemaking in this defined subpopulation of DA neurons. We found that the shape of the oAP and its first derivative, as a proxy for extracellularly recorded APs, is highly distinct from spontaneous APs (sAPs) of the same neurons and systematically varies across the pacemaker duty cycle. The timing of the oAP also affects the backbone oscillator of the intrinsic pacemaker by introducing transient "compensatory pauses". Characterizing this systematic interplay between oAPs and sAPs in defined DA neurons will also facilitate a refinement of DA neuron optotagging in vivo.


Assuntos
Neurônios Dopaminérgicos , Optogenética , Camundongos , Animais , Neurônios Dopaminérgicos/fisiologia , Potenciais de Ação/fisiologia , Mesencéfalo , Parte Compacta da Substância Negra , Substância Negra/fisiologia
12.
Arterioscler Thromb Vasc Biol ; 43(10): 2008-2022, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37615112

RESUMO

BACKGROUND: Near-infrared fluorescence indocyanine green lymphangiography, a primary modality for detecting lymphedema, which is a disease due to lymphatic obstruction, enables real-time observations of lymphatics and reveals not only the spatial distribution of drainage (static analysis) but also information on the lymphatic contraction (dynamic analysis). METHODS: We have produced total lymphatic obstruction in the upper limbs of 18 Sprague-Dawley rats through the dissection of proximal (brachial and axillary) lymph nodes and 20-Gy radiation (dissection limbs). After the model formation for 1 week, 9 animal models were observed for 6 weeks using near-infrared fluorescence indocyanine green lymphangiography by injecting 6-µL ICG-BSA (indocyanine green-bovine serum albumin) solution of 20-µg/mL concentration. The drainage pattern and leakage of lymph fluid were evaluated and time-domain signals of lymphatic contraction were observed in the distal lymphatic vessels. The obtained signals were converted to frequency-domain spectrums using signal processing. RESULTS: The results of both static and dynamic analyses proved to be effective in accurately identifying the extent of lymphatic disruption in the dissection limbs. The static analysis showed abnormal drainage patterns and increased leakage of lymph fluid to the periphery of the vessels compared with the control (normal) limbs. Meanwhile, the waveforms were changed and the contractile signal frequency increased by 58% in the dynamic analysis. Specifically, our findings revealed that regular lymphatic contractions, observed at a frequency range of 0.08 to 0.13 Hz in the control limbs, were absent in the dissection limbs. The contractile regularity was not fully restored for the follow-up period, indicating a persistent lymphatic obstruction. CONCLUSIONS: The dynamic analysis could detect the abnormalities of lymphatic circulation by observing the characteristics of signals, and it provided additional evaluation indicators that cannot be provided by the static analysis. Our findings may be useful for the early detection of the circulation problem as a functional evaluation indicator of the lymphatic system.


Assuntos
Vasos Linfáticos , Linfedema , Animais , Ratos , Linfografia/métodos , Verde de Indocianina , Fluorescência , Ratos Sprague-Dawley , Vasos Linfáticos/diagnóstico por imagem , Vasos Linfáticos/patologia , Linfedema/diagnóstico por imagem , Linfedema/patologia
13.
J Nat Prod ; 87(1): 58-67, 2024 01 26.
Artigo em Inglês | MEDLINE | ID: mdl-38159296

RESUMO

Phytochemical investigation of the MeOH extract of Pinus eldarica needles led to the isolation and identification of a new clerodane-type diterpene, pinuseldarone (1), along with a known flavonoid, 5,4'-dihydroxy-3,7,8-trimethoxy-6-C-methylflavone (2), through HPLC purification. The structure of the new compound 1 was elucidated using spectroscopic methods, including 1D and 2D NMR, as well as HRESIMS. Its absolute configuration was established through NOESY analysis and computational methods, including electronic circular dichroism (ECD) calculations and gauge-including atomic orbital NMR chemical shift calculations, followed by DP4+ probability analysis. The metabolic implications of the isolated compounds were assessed using a cultured brown adipocyte model derived from murine brown adipose tissue. It was observed that treatment with dihydroxy-3,7,8-trimethoxy-6-C-methylflavone (2) downregulates the adipogenic marker C/EBPδ and fatty acid transporter CD36, resulting in a significant reduction in lipid accumulation during brown adipocyte differentiation. However, pinuseldarone (1) treatment did not affect brown adipocyte differentiation. Interestingly, pretreatment with pinuseldarone (1) potentiated the pharmacological stimulation of brown adipocytes, seemingly achieved by sensitizing their response to ß3-adrenoreceptor signaling. Therefore, our findings indicate that phytochemicals derived from P. eldarica needles could potentially serve as valuable compounds for adjusting the metabolic activity of brown adipose tissue, a vital component in maintaining whole-body metabolic homeostasis.


Assuntos
Diterpenos Clerodânicos , Pinus , Animais , Camundongos , Adipogenia , Adipócitos Marrons/metabolismo , Termogênese
14.
J Chem Phys ; 160(10)2024 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-38456534

RESUMO

Molybdenum disulfide (MoS2), a semiconducting two-dimensional layered transition metal dichalcogenide (2D TMDC), with attractive properties enables the opening of a new electronics era beyond Si. However, the notoriously high contact resistance (RC) regardless of the electrode metal has been a major challenge in the practical applications of MoS2-based electronics. Moreover, it is difficult to lower RC because the conventional doping technique is unsuitable for MoS2 due to its ultrathin nature. Therefore, the metal-insulator-semiconductor (MIS) architecture has been proposed as a method to fabricate a reliable and stable contact with low RC. Herein, we introduce a strategy to fabricate MIS contact based on atomic layer deposition (ALD) to dramatically reduce the RC of single-layer MoS2 field effect transistors (FETs). We utilize ALD Al2O3 as an interlayer for the MIS contact of bottom-gated MoS2 FETs. Based on the Langmuir isotherm, the uniformity of ALD Al2O3 films on MoS2 can be increased by modulating the precursor injection pressures even at low temperatures of 150 °C. We discovered, for the first time, that film uniformity critically affects RC without altering the film thickness. Additionally, we can add functionality to the uniform interlayer by adopting isopropyl alcohol (IPA) as an oxidant. Tunneling resistance across the MIS contact is lowered by n-type doping of MoS2 induced by IPA as the oxidant in the ALD process. Through a highly uniform interlayer combined with strong doping, the contact resistance is improved by more than two orders of magnitude compared to that of other MoS2 FETs fabricated in this study.

15.
Artigo em Inglês | MEDLINE | ID: mdl-39187003

RESUMO

OBJECTIVES: To investigate whether machine learning (ML)-based center of pressure (COP) analysis for gait assessment, when used in conjunction with clinical information, offers additive benefits in predicting functional outcomes in patients with acute ischemic stroke. DESIGN: A prospective, single-center cohort study. SETTING: A tertiary hospital setting. PARTICIPANTS: A total of 185 patients with acute ischemic stroke, capable of walking 10 m with or without a gait aid by day 7 postadmission. From these patients, 10,804 pairs of consecutive footfalls were included for analysis. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: The dependent variable was a 3-month poor functional outcome, defined as modified Rankin scale score ≥2. For independent variables, 65 clinical variables including demographics, anthropometrics, comorbidities, laboratory data, questionnaires, and drug history were included. Gait function was evaluated using a pressure-sensitive mat. Time-series COP data were parameterized into spatial and temporal variables and analyzed with logistic regression and 2 ML models (light gradient-boosting machine and multilayer perceptron [MLP]). We derived GAIT-AI output scores from the best-performing model analyzed COP data and constructed multivariable logistic regression models using clinical variables and the GAIT scores. RESULTS: Among the included patients, 70 (37.8%) experienced unfavorable outcomes. The MLP model demonstrated the highest predictive performance with an area under the receiver operating characteristic curve (AUROC) of 0.799. Multivariable logistic regression identified age, initial National Institutes of Health Stroke Scale, and initial Fall Efficacy Scale-International as associated factors with unfavorable outcomes. The combined multivariable logistic regression incorporating COP-derived output scores improved the AUROC to 0.812. CONCLUSIONS: Gait function, assessed through COP analysis, serves as a significant predictor of functional outcome in patients with acute ischemic stroke. ML-based COP analysis, when combined with clinical data, enhances the prediction of poor functional outcomes.

16.
Eur Neurol ; : 1-10, 2024 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-39068915

RESUMO

INTRODUCTION: Accurately discerning periods of heightened risk of stroke or transient ischemic attack (TIA) recurrence and managing modifiable risk factors are essential for minimizing overall recurrence risk. This study identified differences in the timing of stroke or TIA recurrence based on risk factors and patient characteristics to develop strategies for reducing recurrence in clinical practice. METHODS: We retrospectively selected patients with ischemic stroke or TIA at the Korea University Ansan Hospital Stroke Center between March 2014 and December 2021 using the prospective institutional database of the Korea University Stroke Registry. We collected demographic, clinical data, and categorized participants by recurrence timing (early within or late after 3 months). Using multinomial logistic regression analysis, we examined variables associated with early and late recurrent stroke or TIAs. RESULTS: Among 3,646 patients, 255 experienced a recurrent stroke or TIA and 3,391 experienced their first stroke or TIA. Multinomial logistic regression analysis revealed significant associations between early recurrent stroke or TIA and diabetes mellitus (odds ratio [OR]: 1.98, 95% confidence interval [CI]: 1.25-3.15), other determined etiologies in the Trial of Org 10172 in the Acute Stroke Treatment classification (OR: 3.00, 95% CI: 1.37-6.61), and white matter changes (OR: 1.97, 95% CI: 1.17-3.33). Late recurrence showed a significant correlation with TIA (OR: 2.95, 95% CI: 1.52-5.71) and cerebral microbleeds (OR: 2.22, 95% CI: 1.32-3.75). CONCLUSION: Substantial differences in factors contribute to stroke or TIA recurrence based on timing. Managing the risk of recurrence in clinical practice necessitates accurate identification of heightened risk periods and rigorous control of modifiable risk factors.

17.
BMC Med Ethics ; 25(1): 93, 2024 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-39223644

RESUMO

BACKGROUND: The demand for organ transplants, both globally and in South Korea, substantially exceeds the supply, a situation that might have been aggravated by the enactment of the Life-Sustaining Treatment Decision Act (LSTDA) in February 2018. This legislation may influence emergency medical procedures and the availability of organs from brain-dead donors. This study aimed to assess LSTDA's impact, introduced in February 2018, on organ donation status in out-of-hospital cardiac arrest (OHCA) patients in a metropolitan city and identified related factors. METHODS: We conducted a retrospective analysis of a regional cardiac arrest registry. This study included patients aged 16 or older with cardiac arrest and a cerebral performance category (CPC) score of 5 from January 2015 to December 2022. The exclusion criteria were CPC scores of 1-4, patients under 16 years, and patients declared dead or transferred from emergency departments. Logistic regression analysis was used to analyse factors affecting organ donation. RESULTS: Of the 751 patients included in this study, 47 were organ donors, with a median age of 47 years. Before the LSTDA, there were 30 organ donations, which declined to 17 after its implementation. In the organ donation group, the causes of cardiac arrest included medical (34%), hanging (46.8%), and trauma (19.2%). The adjusted odds ratio for organ donation before the LSTDA implementation was 6.12 (95% CI 3.09-12.12), with non-medical aetiology as associated factors. CONCLUSION: The enactment of the LSTDA in 2018 in South Korea may be linked to reduced organ donations among patients with OHCA, underscoring the need to re-evaluate the medical and legal aspects of organ donation, especially considering end-of-life care decisions.


Assuntos
Parada Cardíaca Extra-Hospitalar , Obtenção de Tecidos e Órgãos , Humanos , Parada Cardíaca Extra-Hospitalar/terapia , Parada Cardíaca Extra-Hospitalar/mortalidade , República da Coreia/epidemiologia , Obtenção de Tecidos e Órgãos/legislação & jurisprudência , Estudos Retrospectivos , Masculino , Pessoa de Meia-Idade , Feminino , Adulto , Idoso , Tomada de Decisões , Doadores de Tecidos/legislação & jurisprudência , Cuidados para Prolongar a Vida/legislação & jurisprudência , Cuidados para Prolongar a Vida/ética , Sistema de Registros
18.
Artigo em Inglês | MEDLINE | ID: mdl-39212512

RESUMO

Objective: To assess the efficacy of pharmacopuncture (PA) in improving lipid profiles of patients under statin therapy. Design and Setting: Single-center retrospective study. Interventions: Fifty-nine patients who were previously under statins were retrospectively analyzed. We injected 10 cc of PA twice or thrice a week for 12 to 16 weeks at the acupoint (CV5). The PA solution was based on aqueous extracts of various herbs: Taraxaci Herba, Artemisiae Annuae Herba, Elsholtziae Herba, Acanthopanacis Cortex, and Rumecis Radix. Main Outcome Measures: Lipid profiles, including total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), and triglyceride (TG) levels, were compared before and after PA treatment within patients. Results: The mean age was 59.03 ± 19.82 years, and 50.8% were women (n=30). TC and LDL-C levels decreased from 233.6 ± 54.6 mg/dL to 202.0 ± 26.4 mg/dL (P = 1.27×10-6) and from 175.1 ± 46.2 mg/dL to 133.1 ± 21.6 mg/dL (P = 1.37×10-10), respectively. Interestingly, HDL-C level increased from 30.4 ± 14.6 mg/dL to 43.1 ± 12.1 mg/dL (P = 4.39×10-10), where men demonstrated better improvement than women (P = 1.73×10-3). Conclusion: Our findings highlight the adjuvant effects of PA treatment on the lipid profile in patients under statins and the sex interaction in HDL-C improvement, which provides a clinical foundation for future clinical trials with personalized treatment strategies to establish the clinical benefits of PA treatment with statins.

19.
J Integr Neurosci ; 23(6): 122, 2024 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-38940090

RESUMO

BACKGROUND: Rheum tanguticum root, cataloged as "Daehwang" in the Korean Pharmacopeia, is rich in various anthraquinones known for their anti-inflammatory and antioxidant properties. Formulations containing Daehwang are traditionally employed for treating neurological conditions. This study aimed to substantiate the antiepileptic and neuroprotective efficacy of R. tanguticum root extract (RTE) against trimethyltin (TMT)-induced epileptic seizures and hippocampal neurodegeneration. METHODS: The constituents of RTE were identified by ultra-performance liquid chromatography (UPLC). Experimental animals were grouped into the following five categories: control, TMT, and three TMT+RTE groups with dosages of 10, 30, and 100 mg/kg. Seizure severity was assessed daily for comparison between the groups. Brain tissue samples were examined to determine the extent of neurodegeneration and neuroinflammation using histological and molecular biology techniques. Network pharmacology analysis involved extracting herbal targets for Daehwang and disease targets for epilepsy from multiple databases. A protein-protein interaction network was built using the Search Tool for the Retrieval of Interacting Genes/Proteins (STRING) database, and pivotal targets were determined by topological analysis. Enrichment analysis was performed using the Database for Annotation, Visualization, and Integrated Discovery (DAVID) tool to elucidate the underlying mechanisms. RESULTS: The RTE formulation was found to contain sennoside A, sennoside B, chrysophanol, emodin, physcion, (+)-catechin, and quercetin-3-O-glucuronoid. RTE effectively inhibited TMT-induced seizures at 10, 30, and 100 mg/kg dosages and attenuated hippocampal neuronal decay and neuroinflammation at 30 and 100 mg/kg dosages. Furthermore, RTE significantly reduced mRNA levels of tumor necrosis factor (TNF-α), glial fibrillary acidic protein (GFAP), and c-fos in hippocampal tissues. Network analysis revealed TNF, Interleukin-1 beta (IL-1ß), Interleukin-6 (IL-6), Protein c-fos (FOS), RAC-alpha serine/threonine-protein kinase (AKT1), and Mammalian target of rapamycin (mTOR) as the core targets. Enrichment analysis demonstrated significant involvement of R. tanguticum components in neurodegeneration (p = 4.35 × 10-5) and TNF signaling pathway (p = 9.94 × 10-5). CONCLUSIONS: The in vivo and in silico analyses performed in this study suggests that RTE can potentially modulate TMT-induced epileptic seizures and neurodegeneration. Therefore, R. tanguticum root is a promising herbal treatment option for antiepileptic and neuroprotective applications.


Assuntos
Anticonvulsivantes , Modelos Animais de Doenças , Epilepsia , Hipocampo , Fármacos Neuroprotetores , Extratos Vegetais , Raízes de Plantas , Rheum , Compostos de Trimetilestanho , Animais , Fármacos Neuroprotetores/farmacologia , Fármacos Neuroprotetores/administração & dosagem , Extratos Vegetais/farmacologia , Extratos Vegetais/administração & dosagem , Rheum/química , Raízes de Plantas/química , Masculino , Anticonvulsivantes/farmacologia , Epilepsia/tratamento farmacológico , Epilepsia/induzido quimicamente , Hipocampo/efeitos dos fármacos , Hipocampo/metabolismo , Doenças Neurodegenerativas/tratamento farmacológico , Simulação por Computador , Farmacologia em Rede , Mapas de Interação de Proteínas , Ratos
20.
Microsurgery ; 44(4): e31171, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38549389

RESUMO

BACKGROUND: With the growing demand for the use of thin perforator flaps, obtaining knowledge on the superficial anatomy of perforators is imperative for stable flap elevation. Conventional modalities for perforator mapping fall short in providing such information. High-frequency ultrasound (HFUS), known for visualizing the superficially located anatomic structures, may potentially fill this void. This study aimed to evaluate the effectiveness of HFUS in the outcome of anterolateral thigh (ALT) and superficial circumflex iliac artery perforator (SCIP) flap-based reconstructions. METHODS: Consecutive patients who underwent free ALT or SCIP flap-based reconstruction from January 2021 to November 2022 were retrospectively reviewed. Perforator mapping was conducted using a handheld Doppler during the first year, while HFUS was used in the latter part. The two techniques were compared in terms of flap harvesting time and perfusion-related complication rates while considering the flap elevation plane. RESULTS: In total, 123 cases were analyzed, including 82 ALT flaps (41 in each group) and 41 SCIP flaps (16 in the Doppler and 25 in the HFUS group). The time required for flap elevation exhibited a tendency to decrease in the HFUS group, with a significant difference observed in cases involving thin flap elevation (super-thin ALT flaps and pure-skin-perforator SCIP flaps). Compared with the Doppler group, the HFUS group demonstrated significantly lower rates of PRCs, particularly partial flap necrosis. This difference remained significant in multivariable analyses. CONCLUSION: Our results suggest that HFUS might be an appealing modality for perforator mapping in cases requiring thin ALT and SCIP flap.


Assuntos
Retalho Perfurante , Procedimentos de Cirurgia Plástica , Humanos , Retalho Perfurante/irrigação sanguínea , Coxa da Perna/cirurgia , Coxa da Perna/irrigação sanguínea , Artéria Ilíaca/cirurgia , Estudos Retrospectivos
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