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1.
Eur J Neurosci ; 59(4): 662-685, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37002805

RESUMO

Cross-frequency coupling (CFC) between brain oscillations during non-rapid-eye-movement (NREM) sleep (e.g. slow oscillations [SO] and spindles) may be a neural mechanism of overnight memory consolidation. Declines in CFC across the lifespan might accompany coinciding memory problems with ageing. However, there are few reports of CFC changes during sleep after learning in older adults, controlling for baseline effects. Our objective was to examine NREM CFC in healthy older adults, with an emphasis on spindle activity and SOs from frontal electroencephalogram (EEG), during a learning night after a declarative learning task, as compared to a baseline night without learning. Twenty-five older adults (M [SD] age = 69.12 [5.53] years; 64% female) completed a two-night study, with a pre- and post-sleep word-pair associates task completed on the second night. SO-spindle coupling strength and a measure of coupling phase distance from the SO up-state were both examined for between-night differences and associations with memory consolidation. Coupling strength and phase distance from the up-state peak were both stable between nights. Change in coupling strength between nights was not associated with memory consolidation, but a shift in coupling phase towards (vs. away from) the up-state peak after learning predicted better memory consolidation. Also, an exploratory interaction model suggested that associations between coupling phase closer to the up-state peak and memory consolidation may be moderated by higher (vs. lower) coupling strength. This study supports a role for NREM CFC in sleep-related memory consolidation in older adults.


Assuntos
Consolidação da Memória , Humanos , Feminino , Masculino , Idoso , Sono , Aprendizagem , Sono REM , Eletroencefalografia
2.
J Clin Psychopharmacol ; 44(1): 30-34, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38011032

RESUMO

BACKGROUND: The cornerstone treatment of delirium is to assess and treat its underlying causes and prevent further complications. Drug therapy may be necessary to control agitation and behavioral symptoms associated with delirium. The aim of this pilot study was to evaluate the feasibility of a randomized placebo controlled trial to evaluate the efficacy and safety of risperidone in the treatment of delirium. METHODS: This was a randomized double-blinded placebo-controlled trial. Patients were enrolled in the study if they were hospitalized and 65 years or older and had a diagnosis of delirium. Delirium Rating Scale revised 98 was used to determine delirium and motor agitation. RESULTS: A total of 14 participants with 57% being men and having a mean age of 86 years were included. There were no statistically significant differences between the risperidone and placebo group for the Delirium Rating Scale revised 98 score. There were no severe adverse reactions reported in the study, and no patients discontinued the study for adverse reactions. CONCLUSIONS: Risperidone at low doses (1 mg daily or less) was well tolerated for the treatment of delirium. Future large-scale trials are needed to evaluate the safety and efficacy of risperidone in the treatment of delirium. This pilot study taught us that the phase 2 RIsperDone DELirium trial will need a multicenter design with more research personnel to increase the number of participants enrolled.


Assuntos
Antipsicóticos , Delírio , Masculino , Humanos , Idoso de 80 Anos ou mais , Feminino , Risperidona/efeitos adversos , Antipsicóticos/efeitos adversos , Projetos Piloto , Delírio/tratamento farmacológico , Delírio/induzido quimicamente , Resultado do Tratamento , Método Duplo-Cego
3.
PLoS Biol ; 19(11): e3001232, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34735431

RESUMO

Sleep deprivation (SD) leads to impairments in cognitive function. Here, we tested the hypothesis that cognitive changes in the sleep-deprived brain can be explained by information processing within and between large-scale cortical networks. We acquired functional magnetic resonance imaging (fMRI) scans of 20 healthy volunteers during attention and executive tasks following a regular night of sleep, a night of SD, and a recovery nap containing nonrapid eye movement (NREM) sleep. Overall, SD was associated with increased cortex-wide functional integration, driven by a rise of integration within cortical networks. The ratio of within versus between network integration in the cortex increased further in the recovery nap, suggesting that prolonged wakefulness drives the cortex towards a state resembling sleep. This balance of integration and segregation in the sleep-deprived state was tightly associated with deficits in cognitive performance. This was a distinct and better marker of cognitive impairment than conventional indicators of homeostatic sleep pressure, as well as the pronounced thalamocortical connectivity changes that occurs towards falling asleep. Importantly, restoration of the balance between segregation and integration of cortical activity was also related to performance recovery after the nap, demonstrating a bidirectional effect. These results demonstrate that intra- and interindividual differences in cortical network integration and segregation during task performance may play a critical role in vulnerability to cognitive impairment in the sleep-deprived state.


Assuntos
Biomarcadores/metabolismo , Encéfalo/fisiopatologia , Transtornos Cognitivos/fisiopatologia , Privação do Sono/fisiopatologia , Comportamento , Córtex Cerebral/fisiopatologia , Análise por Conglomerados , Estado de Consciência , Feminino , Humanos , Masculino , Rede Nervosa/fisiopatologia , Vigília/fisiologia , Adulto Jovem
4.
J Sleep Res ; : e14189, 2024 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-38462491

RESUMO

Sleep loss is associated with reduced health and quality of life, and increased risk of Alzheimer's disease and related dementias. Up to 66% of persons with Alzheimer's disease and related dementias experience poor sleep, which can predict or accelerate the progression of cognitive decline. Exercise is a widely accessible intervention for poor sleep that can protect against functional and cognitive decline. No previous systematic reviews have investigated the effectiveness of exercise for sleep in older adults with mild cognitive impairment or Alzheimer's disease and related dementias. We systematically reviewed controlled interventional studies of exercise targeting subjectively or objectively (polysomnography/actigraphy) assessed sleep in persons with mild cognitive impairment or Alzheimer's disease and related dementias. We conducted searches in PubMed, Embase, Scopus and Cochrane-Library (n = 6745). Nineteen randomised and one non-randomised controlled interventional trials were included, representing the experiences of 3278 persons with mild cognitive impairment or Alzheimer's disease and related dementias. Ten had low-risk, nine moderate-risk, and one high-risk of bias. Six studies with subjective and eight with objective sleep outcomes were meta-analysed (random-effects model). We found moderate- to high-quality evidence for the beneficial effects of exercise on self-reported and objectively-measured sleep outcomes in persons with mild cognitive impairment or Alzheimer's disease and related dementias. However, no studies examined key potential moderators of these effects, such as sex, napping or medication use. Our results have important implications for clinical practice. Sleep may be one of the most important modifiable risk factors for a range of health conditions, including cognitive decline and the progression of Alzheimer's disease and related dementias. Given our findings, clinicians may consider adding exercise as an effective intervention or adjuvant strategy for improving sleep in older persons with mild cognitive impairment or Alzheimer's disease and related dementias.

5.
J Sport Exerc Psychol ; 46(3): 125-136, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38663849

RESUMO

Insomnia treatment among individuals with comorbid insomnia and obstructive sleep apnea is suboptimal. In a pilot randomized controlled trial, 19 individuals with comorbid insomnia and obstructive sleep apnea were allocated to one of two arms: EX + EX, consisting of two 8-week phases of exercise training (EX), or RE + CBTiEX, encompassing 8 weeks of relaxation training (RE) followed by 8 weeks of combined cognitive-behavioral therapy and exercise (CBTiEX). Outcomes included Insomnia Severity Index (ISI), polysomnography, and cardiorespiratory fitness measures. A mixed-model analysis of variance revealed a Group × Time interaction on peak oxygen consumption change, F(1, 14) = 10.1, p = .007, and EX increased peak oxygen consumption (p = .03, g' = -0.41) and reduced ISI (p = .001, g' = 0.82) compared with RE (p = .49, g = 0.16) post-8 weeks. Post-16 weeks, there was a significant Group × Time interaction (p = .014) driven by RE + CBTiEX yielding a larger improvement in ISI (p = .023, g' = 1.48) than EX + EX (p = .88, g' < 0.1). Objective sleep was unchanged. This study showed promising effects of regular EX alone and combined with cognitive-behavioral therapy for insomnia on ISI in comorbid insomnia and obstructive sleep apnea.


Assuntos
Terapia Cognitivo-Comportamental , Terapia por Exercício , Apneia Obstrutiva do Sono , Distúrbios do Início e da Manutenção do Sono , Humanos , Apneia Obstrutiva do Sono/terapia , Apneia Obstrutiva do Sono/complicações , Projetos Piloto , Distúrbios do Início e da Manutenção do Sono/terapia , Distúrbios do Início e da Manutenção do Sono/complicações , Masculino , Feminino , Pessoa de Meia-Idade , Adulto , Polissonografia , Aptidão Cardiorrespiratória , Consumo de Oxigênio , Terapia de Relaxamento , Terapia Combinada
6.
Opt Express ; 31(20): 33565-33581, 2023 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-37859135

RESUMO

By engineering the point-spread function (PSF) of single molecules, different fluorophore species can be imaged simultaneously and distinguished by their unique PSF patterns. Here, we insert a silicon-dioxide phase plate at the Fourier plane of the detection path of a wide-field fluorescence microscope to produce distinguishable PSFs (X-PSFs) at different wavelengths. We demonstrate that the resulting PSFs can be localized spatially and spectrally using a maximum-likelihood estimation algorithm and can be utilized for hyper-spectral super-resolution microscopy of biological samples. We produced superresolution images of fixed U2OS cells using X-PSFs for dSTORM imaging with simultaneous illumination of up to three fluorophore species. The species were distinguished only by the PSF pattern. We achieved ∼21-nm lateral localization precision (FWHM) and ∼17-nm axial precision (FWHM) with an average of 1,800 - 3,500 photons per PSF and a background as high as 130 - 400 photons per pixel. The modified PSF distinguished fluorescent probes with ∼80 nm separation between spectral peaks.

7.
Biomacromolecules ; 24(6): 2633-2642, 2023 06 12.
Artigo em Inglês | MEDLINE | ID: mdl-37075205

RESUMO

Recently, the desire for a safe and effective method for skin whitening has been growing in the cosmetics industry. Commonly used tyrosinase-inhibiting chemical reagents exhibit side effects. Thus, recent studies have focused on performing melanin decolorization with enzymes as an alternative due to the low toxicity of enzymes and their ability to decolorize melanin selectively. Herein, 10 different isozymes were expressed as recombinant lignin peroxidases (LiPs) from Phanerochaete chrysosporium (PcLiPs), and PcLiP isozyme 4 (PcLiP04) was selected due to its high stability and activity at pH 5.5 and 37 °C, which is close to human skin conditions. In vitro melanin decolorization results indicated that PcLiP04 exhibited at least 2.9-fold higher efficiency than that of well-known lignin peroxidase (PcLiP01) in a typical human skin-mimicking environment. The interaction force between melanin films measured by a surface forces apparatus (SFA) revealed that the decolorization of melanin by PcLiP04 harbors a disrupted structure, possibly interrupting π-π stacking and/or hydrogen bonds. In addition, a 3D reconstructed human pigmented epidermis skin model showed a decrease in melanin area to 59.8% using PcLiP04, which suggests that PcLiP04 exhibits a strong potential for skin whitening.


Assuntos
Melaninas , Phanerochaete , Humanos , Peroxidases , Pele , Epiderme , Lignina
8.
AIDS Care ; 35(12): 1928-1937, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-36794343

RESUMO

Disclosure of HIV status is an important part of pediatric care. We studied disclosure and clinical outcomes in a multi-country Asian cohort of children and adolescents with HIV. Those 6-19 years of age who initiated combination antiretroviral therapy (cART) between 2008 and 2018, and who had at least one follow-up clinic visit were included. Data up to December 2019 were analyzed. Cox and competing risk regression analyses were used to assess the effect of disclosure on disease progression (WHO clinical stage 3 or 4), loss to follow-up (LTFU; > 12 months), and death. Of 1913 children and adolescents (48% female; median [IQR] age 11.5 [9.2-14.7] years at last clinic visit), 795 (42%) were disclosed to about their HIV status at a median age of 12.9 years (IQR: 11.8-14.1). During follow-up, 207 (11%) experienced disease progression, 75 (3.9%) were LTFU, and 59 (3.1%) died. There were lower hazards of disease progression (adjusted hazard ratio [aHR] 0.43 [0.28-0.66]) and death (aHR 0.36 [0.17-0.79]) for those disclosed to compared with those who were not. Disclosure and its appropriate implementation should be promoted in pediatric HIV clinics in resource-limited settings.


Assuntos
Revelação , Infecções por HIV , Humanos , Criança , Feminino , Adolescente , Masculino , Infecções por HIV/tratamento farmacológico , Estudos Retrospectivos , Ásia/epidemiologia , Perda de Seguimento , Progressão da Doença
9.
Int J Geriatr Psychiatry ; 38(1): e5879, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36703303

RESUMO

OBJECTIVE: The COVID-19 pandemic and its associated public health measures may increase the risk for psychological distress among vulnerable older adults. This longitudinal study aimed to identify predictors of psychological distress trajectories among community-dwelling older adults in Quebec, Canada. METHODS: The study spanned four time points across 13 months and three waves of the COVID-19 pandemic. The sample included 645 community-dwelling older adults ages 60 years and older in Quebec. Participants completed telephone-based interviews that included the Kessler 6-item Psychological Distress Scale (K6) to assess psychological distress at each time point as well as information on socioeconomic, medical, psychological and COVID-19 related factors. Group-based trajectory modelling was used to identify distinct trajectories of psychological distress across time. RESULTS: Three group-based trajectories of psychological distress were identified: the resilient (50.5%), reactive (34.9%), and elevated distress groups (14.6%). Individuals with mobility issues, insomnia symptoms, COVID-19 related acute stress, general health anxiety, increased loneliness symptoms, and those unable to use technology to see others were more likely to be in the reactive and elevated groups than the resilient group. Those with past mental health problems had uniquely increased odds of being in the reactive group compared to the resilient group. Individuals living in poverty and those who reported taking psychotropic medication had increased odds of being in the elevated distress group compared to the resilient group. CONCLUSION: These findings characterized distinct trajectories of psychological distress in older adults and identified risk factors for elevated distress levels.


Assuntos
COVID-19 , Angústia Psicológica , Humanos , Idoso , COVID-19/epidemiologia , Quebeque/epidemiologia , Estresse Psicológico/epidemiologia , Estresse Psicológico/psicologia , Estudos Longitudinais , Pandemias , Vida Independente
10.
Pediatr Crit Care Med ; 24(10): 818-828, 2023 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-37310173

RESUMO

OBJECTIVES: Pediatric acute liver failure (PALF) is a fatal complication in patients with severe dengue. To date, clinical data on the combination of therapeutic plasma exchange (TPE) and continuous renal replacement therapy (CRRT) for managing dengue-associated PALF concomitant with shock syndrome are limited. DESIGN: Retrospective cohort study (January 2013 to June 2022). PATIENTS: Thirty-four children. SETTING: PICU of tertiary Children's Hospital No. 2 in Vietnam. INTERVENTIONS: We assessed a before-versus-after practice change at our center of using combined TPE and CRRT (2018 to 2022) versus CRRT alone (2013 to 2017) in managing children with dengue-associated acute liver failure and shock syndrome. Clinical and laboratory data were reviewed from PICU admission, before and 24 h after CRRT and TPE treatments. The main study outcomes were 28-day in-hospital mortality, hemodynamics, clinical hepatoencephalopathy, and liver function normalization. MEASUREMENTS AND MAIN RESULTS: A total of 34 children with a median age of 10 years (interquartile range: 7-11 yr) underwent standard-volume TPE and/or CRRT treatments. Combined TPE and CRRT ( n = 19), versus CRRT alone ( n = 15), was associated with lower proportion of mortality 7 of 19 (37%) versus 13 of 15 (87%), difference 50% (95% CI, 22-78; p < 0.01). Use of combined TPE and CRRT was associated with substantial advancements in clinical hepatoencephalopathy, liver transaminases, coagulation profiles, and blood lactate and ammonia levels (all p values < 0.001). CONCLUSIONS: In our experience of children with dengue-associated PALF and shock syndrome, combined use of TPE and CRRT, versus CRRT alone, is associated with better outcomes. Such combination intervention was associated with normalization of liver function, neurological status, and biochemistry. In our center we continue to use combined TPE and CRRT rather than CRRT alone.


Assuntos
Injúria Renal Aguda , Terapia de Substituição Renal Contínua , Dengue , Falência Hepática Aguda , Choque , Criança , Humanos , Troca Plasmática , Estudos Retrospectivos , Vietnã , Terapia de Substituição Renal , Choque/terapia , Falência Hepática Aguda/etiologia , Falência Hepática Aguda/terapia , Injúria Renal Aguda/etiologia , Injúria Renal Aguda/terapia , Dengue/terapia
11.
Chem Biodivers ; 20(6): e202300319, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37183173

RESUMO

Sphaeranthus africanus L. is native in Vietnam. Little is known about α-glucosidase inhibition of Sphaeranthus africanus and its isolated compounds. A bioactive-guided isolation was applied to the Vietnamese Sphaeranthus africanus to find α-glucosidase inhibitory components. Eight compounds were detected and structurally elucidated. They are 3-angeloyloxy-5-[2'',3''-epoxy-2''-methylbutanoyloxy]-7-hydroxycarvotacetone, 3-angeloyloxy-5-[3''-chloro-2''-hydroxy-2''-methylbutanoyloxy]-7-hydroxycarvotacetone, 3-angeloyloxy-5-[2''R,3''R-dihydroxy-2''-methyl-butanoyloxy]-7-hydroxycarvotacetone, 3-angeloyloxy-5-[2''S,3''R-dihydroxy-2''-methylbutanoyloxy]-7-hydroxycarvotacetone, 3-angeloyloxy-5-[2''S,3''S-dihydroxy-2''-methylbutanoyloxy]-7-hydroxycarvotacetone, 5-angeloyloxy-7-hydroxy-3-tigloyloxycarvotacetone, 3-O-methylquercetin, and chrysosplenol D. Their chemical structures were elucidated by extensive 1D and 2D NMR analysis and high-resolution mass spectroscopy as well as comparisons in literature. 3-Angeloyloxy-5-[2''S,3''S-dihydroxy-2''-methylbutanoyloxy]-7-hydroxycarvotacetone is a new compound. Isolated compounds were evaluated for the α-glucosidase inhibition. Isolated compounds showed moderate activity with IC50 values ranging from 128.9-274.3 µM while others are weak. A molecular docking study was conducted, indicating that isolated compounds are potent α-glucosidase inhibitory compounds.


Assuntos
Asteraceae , Extratos Vegetais , Extratos Vegetais/química , Simulação de Acoplamento Molecular , alfa-Glucosidases , Asteraceae/química , Componentes Aéreos da Planta/química , Estrutura Molecular
12.
J Comput Chem ; 43(3): 160-169, 2022 01 30.
Artigo em Inglês | MEDLINE | ID: mdl-34716930

RESUMO

AutoDock Vina (Vina) achieved a very high docking-success rate, p^ , but give a rather low correlation coefficient, R , for binding affinity with respect to experiments. This low correlation can be an obstacle for ranking of ligand-binding affinity, which is the main objective of docking simulations. In this context, we evaluated the dependence of Vina R coefficient upon its empirical parameters. R is affected more by changing the gauss2 and rotation than other terms. The docking-success rate p^ is sensitive to the alterations of the gauss1, gauss2, repulsion, and hydrogen bond parameters. Based on our benchmarks, the parameter set1 has been suggested to be the most optimal. The testing study over 800 complexes indicated that the modified Vina provided higher correlation with experiment Rset1=0.556±0.025 compared with RDefault=0.493±0.028 obtained by the original Vina and RVina1.2=0.503±0.029 by Vina version 1.2. Besides, the modified Vina can be also applied more widely, giving R≥0.500 for 32/48 targets, compared with the default package, giving R≥0.500 for 31/48 targets. In addition, validation calculations for 1036 complexes obtained from version 2019 of PDBbind refined structures showed that the set1 of parameters gave higher correlation coefficient ( Rset1=0.617±0.017 ) than the default package ( RDefault=0.543±0.020 ) and Vina version 1.2 ( RVina1.2=0.540±0.020 ). The version of Vina with set1 of parameters can be downloaded at https://github.com/sontungngo/mvina. The outcomes would enhance the ranking of ligand-binding affinity using Autodock Vina.

13.
J Sleep Res ; 31(5): e13578, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35253300

RESUMO

The discrepancies in the effects of napping on sleep quality may be due to differences in methodologies, napping behaviours, and daytime activity levels across studies. We determined whether napping behaviours and daytime activity levels are associated with night-time sleep fragmentation and sleep quality in young adults. A total of 62 healthy adults (mean [SD] age 23.5 [4.2] years) completed screening questionnaires for sleep habits, physical activity, medical and psychological history. Actigraphy was used to record sleep including naps. The fragmentation algorithm (KRA ) was applied to the actigraphic data to measure night-time sleep fragmentation. We classified participants' nap frequency as "non-nappers" (0 naps/8 days), "moderate nappers" (1-2 naps/8 days) or "frequent nappers" (≥3 naps/8 days) naps. Nap duration was defined as "short" (≤60 min) or "long" (>60 min). Naps' proximity to the night sleep episode was defined as "early" (≥7 h) and "late" (<7 h) naps. Outcome variables were night-time KRA and actigraphic sleep variables. Frequent nappers had a significantly higher KRA than moderate nappers (p < 0.01) and non-nappers (p < 0.02). Late naps were associated with poorer measures of night sleep quality versus early naps (all p ≤ 0.02). Nap duration and daytime activity were not associated with significant differences in the outcome variables (all p > 0.05). KRA correlated with sleep duration, sleep efficiency, and awakenings (r = -0.32, -0.32, and 0.53, respectively; all p < 0.05). Frequent napping and late naps may be associated with increased sleep fragmentation and poorer sleep quality, reflected in longer sleep onsets and increased awakenings. These findings have implications for public health sleep hygiene recommendations.


Assuntos
Privação do Sono , Distúrbios do Início e da Manutenção do Sono , Adulto , Humanos , Adulto Jovem , Actigrafia , Sono
14.
Chem Biodivers ; 19(4): e202100882, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35146904

RESUMO

Four compounds, luteolin (1), 6-γ,γ-dimethylallylquercetin 7-O-ß-D-glucopyranoside (2), 6-γ,γ-dimethylallylkaempferol 7-O-ß-D-glucopyranoside (3), and 6-γ,γ-dimethylallyldihydrokaempferol 7-O-ß-D-glucoside (4), were isolated for the first time from AcOEt extract of the O. integerrima flower. We then evaluated the antioxidant effects of AcOEt, butanol, and MeOH extracts and their effects on H2 O2 against oxidative stress in HaCaT keratinocyte cell lines. Furthermore, 2,2-diphenyl-1-picrylhydrazyl hydrate (DPPH⋅) radical scavenging activities of 1-4 were determined and their mechanisms of action on tyrosinase were predicted by in silico studies. The results revealed that the AcOEt extract and 1-3 exhibited good DPPH⋅ radical scavenging activity. Furthermore, this extract also had a significant protective effect against H2 O2 -induced oxidative stress in HaCaT cells. In silico studies indicated that the activity of 1-3 may be due to tyrosinase inhibition with MM-GBSA free binding energies of -78.9, -70.1, and -71.1 kcal mol-1 , respectively, compared to 4 with an energy -56.9 kcal mol-1 .


Assuntos
Antioxidantes , Ochnaceae , Antioxidantes/química , Antioxidantes/farmacologia , Flores , Queratinócitos , Monofenol Mono-Oxigenase , Extratos Vegetais/química , Extratos Vegetais/farmacologia
15.
Physiology (Bethesda) ; 35(1): 4-15, 2020 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-31799908

RESUMO

Sleep can benefit memory consolidation. The characterization of brain regions underlying memory consolidation during sleep, as well as their temporal interplay, reflected by specific patterns of brain electric activity, is surfacing. Here, we provide an overview of recent concepts and results on the mechanisms of sleep-related memory consolidation. The latest studies strongly impacting future directions of research in this field are highlighted.


Assuntos
Encéfalo/fisiologia , Consolidação da Memória/fisiologia , Memória/fisiologia , Sono/fisiologia , Ritmo Circadiano/fisiologia , Eletroencefalografia/métodos , Humanos
16.
Neuroimage ; 226: 117547, 2021 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-33186718

RESUMO

Sleep deprivation leads to significant impairments in cognitive performance and changes to the interactions between large scale cortical networks, yet the hierarchical organization of cortical activity across states is still being explored. We used functional magnetic resonance imaging to assess activations and connectivity during cognitive tasks in 20 healthy young adults, during three states: (i) following a normal night of sleep, (ii) following 24hr of total sleep deprivation, and (iii) after a morning recovery nap. Situating cortical activity during cognitive tasks along hierarchical organizing gradients based upon similarity of functional connectivity patterns, we found that regional variations in task-activations were captured by an axis differentiating areas involved in executive control from default mode regions and paralimbic cortex. After global signal regression, the range of functional differentiation along this axis at baseline was significantly related to decline in working memory performance (2-back task) following sleep deprivation, as well as the extent of recovery in performance following a nap. The relative positions of cortical regions within gradients did not significantly change across states, except for a lesser differentiation of the visual system and increased coupling of the posterior cingulate cortex with executive control areas after sleep deprivation. This was despite a widespread increase in the magnitude of functional connectivity across the cortex following sleep deprivation. Cortical gradients of functional differentiation thus appear relatively insensitive to state-dependent changes following sleep deprivation and recovery, suggesting that there are no large-scale changes in cortical functional organization across vigilance states. Certain features of particular gradient axes may be informative for the extent of decline in performance on more complex tasks following sleep deprivation, and could be beneficial over traditional voxel- or parcel-based approaches in identifying realtionships between state-dependent brain activity and behavior.


Assuntos
Encéfalo/diagnóstico por imagem , Cognição/fisiologia , Privação do Sono/diagnóstico por imagem , Vigília/fisiologia , Adolescente , Adulto , Encéfalo/fisiopatologia , Eletroencefalografia , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Testes Neuropsicológicos , Privação do Sono/fisiopatologia , Privação do Sono/psicologia , Adulto Jovem
17.
Hum Brain Mapp ; 42(12): 3993-4021, 2021 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-34101939

RESUMO

Simultaneous recording of electroencephalography (EEG) and functional magnetic resonance imaging (fMRI) is a very promising non-invasive neuroimaging technique. However, EEG data obtained from the simultaneous EEG-fMRI are strongly influenced by MRI-related artefacts, namely gradient artefacts (GA) and ballistocardiogram (BCG) artefacts. When compared to the GA correction, the BCG correction is more challenging to remove due to its inherent variabilities and dynamic changes over time. The standard BCG correction (i.e., average artefact subtraction [AAS]), require detecting cardiac pulses from simultaneous electrocardiography (ECG) recording. However, ECG signals are also distorted and will become problematic for detecting reliable cardiac peaks. In this study, we focused on a beamforming spatial filtering technique to attenuate all unwanted source activities outside of the brain. Specifically, we applied the beamforming technique to attenuate the BCG artefact in EEG-fMRI, and also to recover meaningful task-based neural signals during an attentional network task (ANT) which required participants to identify visual cues and respond accurately. We analysed EEG-fMRI data in 20 healthy participants during the ANT, and compared four different BCG corrections (non-BCG corrected, AAS BCG corrected, beamforming + AAS BCG corrected, beamforming BCG corrected). We demonstrated that the beamforming approach did not only significantly reduce the BCG artefacts, but also significantly recovered the expected task-based brain activity when compared to the standard AAS correction. This data-driven beamforming technique appears promising especially for longer data acquisition of sleep and resting EEG-fMRI. Our findings extend previous work regarding the recovery of meaningful EEG signals by an optimized suppression of MRI-related artefacts.


Assuntos
Balistocardiografia/normas , Eletroencefalografia/normas , Neuroimagem Funcional/normas , Imageamento por Ressonância Magnética/normas , Adulto , Artefatos , Balistocardiografia/métodos , Eletroencefalografia/métodos , Feminino , Neuroimagem Funcional/métodos , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Adulto Jovem
18.
Circ J ; 85(7): 1076-1082, 2021 06 25.
Artigo em Inglês | MEDLINE | ID: mdl-34092755

RESUMO

BACKGROUND: Risk factors for atherosclerotic disease including dyslipidemia have been shown to be associated with aortic valve calcification (AVC). Nuclear magnetic resonance (NMR)-measured lipoprotein particles, low-density and high-density lipoprotein particles (LDL-p, HDL-p) in particular, have emerged as novel markers of atherosclerotic disease; however, whether NMR-measured particles are associated with AVC remains to be determined. This study aimed to examine the association between NMR-based lipoprotein particle measurements and standard lipids with AVC. The primary variables of interest were LDL-p (nmol/L), HDL-p (µmol/L), LDL-cholesterol, and HDL-cholesterol (both in mg/dL).Methods and Results:A community-based random sample of Japanese men aged 40-79 years examined in 2006-2008, in Shiga, Japan was studied. Presence of AVC was defined as an Agatston score >0. Lipoprotein particles were measured using NMR spectroscopy. In the main analysis, multivariable-adjusted odds ratios (ORs) and 95% confidence intervals (95% CIs) for the prevalence of AVC across the higher quartiles of lipids in reference to the lowest ones were obtained. Of 874 participants analyzed, 153 men had AVC. Multivariable-adjusted ORs of prevalent AVC for the highest vs. the lowest quartile were significantly elevated for LDL-p (OR, 2.20; 95% CI: 1.23-3.93) and LDL-cholesterol (OR, 2.16; 95% CI: 1.23-3.78). In contrast, neither HDL-p nor HDL-cholesterol was associated with AVC. CONCLUSIONS: The association of prevalent AVC with NMR-based LDL-p was comparable to that with LDL-cholesterol.


Assuntos
Valva Aórtica , Aterosclerose , Valva Aórtica/diagnóstico por imagem , Valva Aórtica/patologia , Estenose da Valva Aórtica , Calcinose , HDL-Colesterol , LDL-Colesterol , Humanos , Japão/epidemiologia , Lipídeos , Masculino
19.
Chem Biodivers ; 18(4): e2001008, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33660915

RESUMO

A new xanthone derivative, aspidxanthone A (1), and three known compounds ((2S)-1-(ß-D-galactopyranosyloxy)-3-(hexadecanoyloxy)propan-2-yl (9Z,12Z)-octadeca-9,12-dienoate (2), (25S)-spirostane-1ß,3α,5ß-triol (3), and asparenyldiol (4)) were isolated from the whole of the endemic species Aspidistra letreae in Vietnam. Their structures were elucidated by means of extensive spectroscopic analyses and comparison with published data. In this study, we report the isolation and structure elucidation of a new compound aspidxanthone A, antioxidant activities of the extract and isolates 1-4, and in silico molecular docking of aspidxanthone A. The ethyl acetate extract had good antioxidant activity with an IC50 value of 26.3 µg mL-1 . Among the isolates, aspidxanthone A exhibited DPPH reduction activity with an IC50 value of 11.2 µM, which is in the same range as that of the positive control, ascorbic acid. The mechanism of action of aspidxanthone A on the tyrosinase and xanthine oxidase proteins have been clarified by in silico studies.


Assuntos
Antioxidantes/farmacologia , Asparagaceae/química , Xantonas/farmacologia , Antioxidantes/química , Antioxidantes/isolamento & purificação , Compostos de Bifenilo/antagonistas & inibidores , Teoria da Densidade Funcional , Relação Dose-Resposta a Droga , Simulação de Acoplamento Molecular , Estrutura Molecular , Picratos/antagonistas & inibidores , Xantonas/química , Xantonas/isolamento & purificação
20.
Heart Surg Forum ; 24(2): E333-E335, 2021 03 30.
Artigo em Inglês | MEDLINE | ID: mdl-33798041

RESUMO

Right ventricular myxoma is very rare, especially its originating from the right ventricular outflow tract (RVOT) and extending to the main pulmonary artery. Here, we report a case of a giant RVOT myxoma, indistinguishable from pulmonary embolism (PE). Although the myxoma is a candidate for urgent surgery, this case satisfied diagnostic criteria for PE and had no indication for intervention, according to the guideline. The strategy for this mass can be completely different, depending on the diagnosis. Surgical extraction was selected because of atypical clinical course, findings, and nagging debut for neoplasm. Then it made hemodynamic status stable by releasing RVOT obstruction and allowed to reveal the diagnosis as myxoma histopathologically.


Assuntos
Neoplasias Cardíacas/diagnóstico , Mixoma/diagnóstico , Embolia Pulmonar/diagnóstico , Obstrução do Fluxo Ventricular Externo/etiologia , Idoso , Procedimentos Cirúrgicos Cardíacos/métodos , Neoplasias Cardíacas/complicações , Neoplasias Cardíacas/cirurgia , Ventrículos do Coração , Humanos , Masculino , Mixoma/complicações , Mixoma/cirurgia , Índice de Gravidade de Doença , Tomografia Computadorizada por Raios X , Obstrução do Fluxo Ventricular Externo/diagnóstico , Obstrução do Fluxo Ventricular Externo/cirurgia
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