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Electrochemical oxygen reduction reaction (ORR) and carbon dioxide reduction reaction (CO2RR) are greatly significant in renewable energy-related devices and carbon-neutral closed cycle, while the development of robust and highly efficient electrocatalysts has remained challenges. Herein, a hybrid electrocatalyst, featuring axial N-coordinated Fe single atom sites on hierarchically N, P-codoped porous carbon support and Fe nanoclusters as electron reservoir (FeNCs/FeSAs-NPC), is fabricated via in situ thermal transformation of the precursor of a supramolecular polymer initiated by intermolecular hydrogen bonds co-assembly. The FeNCs/FeSAs-NPC catalyst manifests superior oxygen reduction activity with a half-wave potential of 0.91 V in alkaline solution, as well as high CO2 to CO Faraday efficiency (FE) of surpassing 90% in a wide potential window from -0.40 to -0.85 V, along with excellent electrochemical durability. Theoretical calculations indicate that the electron reservoir effect of Fe nanoclusters can trigger the electron redistribution of the atomic Fe moieties, facilitating the activation of O2 and CO2 molecules, lowering the energy barriers for rate-determining step, and thus contributing to the accelerated ORR and CO2RR kinetics. This work offers an effective design of electron coupling catalysts that have advanced single atoms coexisting with nanoclusters for efficient ORR and CO2RR.
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Aerosols produced in the amine carbon capture process can lead to secondary environmental pollution. This study employs molecular dynamics (MD) simulations to investigate cluster formation, amine behavior, and aerosol growth of amines, essential for reducing amine aerosol emissions. Results showed that the cluster evolution process can be divided into cluster formation and growth in terms of molecular content, and the nucleation rate for the present systems was estimated in the order of 1028 cm-3 s-1. CO2 absorption was observed alongside successful nucleation, with CO2 predominantly localizing in the cluster's outer layer postabsorption. Monoethanolamine (MEA) exhibited robust electrostatic interactions with other components via hydrogen bonding, leading to its migration toward regions where CO2 and H2O coexisted within the cluster. While MEA presence markedly spurred cluster formation, its concentration had a marginal effect on the final cluster size. Elevating water content can augment the aerosol growth rate. However, altering the gas saturation is possible only within narrow confines by introducing vapor. Contrarily, gas cooling introduced dual, opposing effects on aerosol growth. These findings, including diffusion coefficients and growth rates, enhance theoretical frameworks for predicting aerosol formation in absorbers, aiding in mitigating environmental impacts of amine-based carbon capture.
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Aerossóis , Dióxido de Carbono , Dióxido de Carbono/química , Simulação de Dinâmica Molecular , Aminas/químicaRESUMO
Derailment is the sense of being "off-course" in life. But what could this mean for adolescents, who are often establishing identity and self-direction for the first time? We examined the structure and correlates of the Derailment Scale and its short form, the Derailment Scale-6 (DS-6), among middle-to-late adolescents (N = 452). Both scales exhibited unidimensionality, but the DS-6 demonstrated superior fit and correlated with cross-sectional distress markers (e.g., greater depression, lower life satisfaction, strained sense of purpose). Breaking from adult-based research, we failed to find evidence that derailment related to adolescent identity exploration and commitment. In extending assessment of derailment to adolescence, this study invites exploration of this experience during a time characterized by substantial transition and the emergence of stable self-views.
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Trilobatin is a flavonoid that has wide application prospects due to its various pharmacological effects, such as anti-inflammation and anti-oxidation. In this work, a novel electrochemical sensor based on gold nanobipyramids (AuNBs) and L-cysteine (L-cys) was constructed for the sensitive and selective determination of trilobatin. The AuNBs, which were prepared by a seed-mediated growth method, had large specific surface areas and excellent electrical conductivity. A layer of L-cys film, which provided more active sites through the amino and hydroxyl groups, was modified on the surface of the AuNBs by electropolymerization. Significantly, the Au-S bond between the L-cys film and AuNBs could improve the stability of the sensor and it exhibited satisfactory electrocatalytic oxidation activity for trilobatin. Under optimized conditions, the sensor based on poly-L-cys/AuNBs/GCE was used to determine trilobatin by differential pulse voltammetry (DPV). Two wide linear ranges between the current peak and the concentration of trilobatin were obtained in the range from 5 to 100 µM and 100 to 1000 µM, and the low detection limit (LOD) was up to 2.55 µM (S/N = 3). The sensor demonstrated desirable reproducibility, stability, and selectivity and was applied to detect real trilobatin samples extracted from Lithocarpus polystachyus Rehd.'s leaves, showing recoveries of 98.36%-104.96%, with satisfactory results.
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Cisteína , Ouro , Ouro/química , Reprodutibilidade dos Testes , Oxirredução , Técnicas Eletroquímicas , EletrodosRESUMO
OBJECTIVE: Despite long-standing assumptions that a sense of purpose in life and goal pursuit are mutually supportive, empirical evidence of their reciprocity remains deficient. In the context of a unique out-of-school time program that empowers youth to pursue passions through self-driven learning, we examined whether purpose and one aspect of goal pursuit-perceptions of goal progress-work together to sustain themselves and each other over time. METHOD: Adolescents (N = 321) completed daily surveys throughout program enrollment (Menrollment = 69.09 days). Through dynamic structural equation modeling, we derived within-person patterns of day-to-day prediction as well as individual differences in these patterns. RESULTS: We found purpose and perceived goal progress exhibited significant daily inertia (i.e., autoregressive prediction) and reciprocity (i.e., cross-lagged prediction) at the within-person level. We also found initial evidence suggesting (a) tighter reciprocity was related to greater perceived goal progress overall and (b) people with greater purpose inertia may rely less on making goal progress to sustain momentum. CONCLUSIONS: With evidence of daily purpose-progress reciprocity, the field can look forward to replicating this work in other contexts, diving deeper into interesting patterns of within-person dynamics, and developing interventions to support youth striving.
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INTRODUCTION: Supportive adults are a critical component of effective out-of-school time (OST) youth programs, yet the short-term dynamics that underlie their role are poorly understood. Within GripTape, a US-wide self-driven learning program, we examined if interactions with program-assigned adults (i.e., Champions) correspond with youths' daily psychosocial functioning (i.e., sense of purpose, self-concept clarity, and self-esteem). METHOD: Participants were 204 North American adolescents (M [SD] = 16.42 [1.18] years; female = 70.1%, male = 25.0%) enrolled in GripTape, a remote OST program that empowers under-resourced teens to pursue their passions for ~10 weeks. During enrollment, youth are given autonomy to structure their learning goals and methods to best match their needs; a stipend of up to 500 USD; and an adult Champion to act as a touchpoint. Data collection consisted of a baseline survey before the program launch and a 5-min survey on each day of enrollment. RESULTS: Across ~70 days, we found that youth reported greater psychosocial functioning on days they reported interacting with their Champion. After controlling for same-day psychosocial functioning, we failed to find evidence that Champion interactions predicted youths' next-day psychosocial functioning. CONCLUSION: In addition to being among the first studies to investigate the daily benefits of youth-adult interactions within OST programming, this study documents the short-term incremental change that may underlie previous work on OST program outcomes.
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Funcionamento Psicossocial , Autoimagem , Humanos , Masculino , Adolescente , Adulto , Feminino , Instituições Acadêmicas , Inquéritos e QuestionáriosRESUMO
BACKGROUND: Racial disparities in psychological distress associated with COVID-19 remain unclear in the U.S. This study aims to investigate the associations between social determinants of health and COVID-19-related psychological distress across different racial/ethnic groups in the US (i.e., non-Hispanic Whites, Hispanic, non-Hispanic Asians, and non-Hispanic African Americans). METHODS: This study used cross-sectional data from the 2020 California Health Interview Survey Adult Data Files (N = 21,280). Adjusting for covariates-including age, gender, COVID-19 pandemic challenges, and risk of severe illness from COVID-19-four sets of weighted binary logistic regressions were conducted. RESULTS: The rates of moderate/severe psychological distress significantly varied across four racial/ethnic groups (p < 0.001), with the highest rate found in the Hispanic group. Across the five domains of social determinants of health, we found that unemployment, food insecurity, housing instability, high educational attainment, usual source of health care, delayed medical care, and low neighborhood social cohesion and safety were associated with high levels of psychological distress in at least one racial/ethnic group (p < 0.05). CONCLUSION: Our study suggests that Hispanic adults face more adverse social determinants of health and are disproportionately impacted by the pandemic. Public health practice and policy should highlight social determinants of heath that are associated with different racial/ethnic groups and develop tailored programs to reduce psychological distress.
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COVID-19 , Angústia Psicológica , Adulto , Humanos , Etnicidade , COVID-19/epidemiologia , Pandemias , Determinantes Sociais da Saúde , Estudos TransversaisRESUMO
OBJECTIVES: Neurodegenerative diseases (NDs), such as Parkinson's disease and Alzheimer's disease and related dementias, are a leading cause of death and disability in China. Although studies have demonstrated that depression is associated with NDs, little is known about the factors impacting this relationship. This study aimed to explore and identify the risk and protective factors of depression among Chinese older adults with NDs. METHODS: Data selection was based on the behavioral model of late-life depression. Data from the latest wave of the Chinese Longitudinal Healthy Longevity Survey (CLHLS, 1998-2014) in 2014 were analyzed. Among the sample, 334 older adults aged 65 and older with NDs were included in the analysis. A logistic regression analysis was conducted by SPSS 24.0. RESULTS: Participants who lived in urban areas (O.R.= 2.494, p< .05) or needed more support for Activity of Daily Living (O.R.= 1.136, p< .05) were more likely to have depression. Participants who lived with household members (O.R.= .380, p< .05), self-reported their health status as fair (O.R.= .250, p< .01), or believed their health status remained the same (O.R.= .331, p< .01) were less likely to have depression. CONCLUSION: Our findings suggest that policymakers and healthcare professionals should pay specific attention to the regional disparities of healthcare services and the cultural background to understand the relationship between NDs and depression and improve the well-being of ND patients.
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Depressão , Doenças Neurodegenerativas , Idoso , Povo Asiático , China/epidemiologia , Depressão/epidemiologia , Nível de Saúde , Humanos , Estudos Longitudinais , Doenças Neurodegenerativas/epidemiologiaRESUMO
Fluorescence quenching of rhodamine 6G by graphene oxide (GO) was investigated using steady-state fluorescence spectroscopy and ultrafast time-resolved absorption spectroscopy. The steady-state fluorescence spectra showed that rhodamine 6G fluorescence was effectively quenched by titrating the GO to the rhodamine 6G solutions. For lower GO concentrations, transient dynamic curves followed two-exponential decay parameters. For higher GO concentrations, the dynamic curves could not be fitted well, and three-exponential decay parameters were appropriate. The results indicated that there was a new transition process (electron transfer) in the exited rhodamine 6G and GO solution.
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Grafite , Rodaminas , Espectrometria de FluorescênciaRESUMO
Sulfuric acid aerosol (SAA) can considerably deteriorate air visibility, which poses a threat to human health. Pretreatment methods that enlarge SAA sizes are crucial to enhanced emission control from industrials. This study provides an insight into SAA growth in terms of aerosol dynamics simulation and growth experiments under simulated flue gas conditions. Results show that SAA growth dynamics are dominated by coagulation and condensation mechanisms for small and large aerosols, respectively. The two mechanisms are coupled mainly in SAA sizes smaller than 0.05 µm. A large amount of time was allotted for the SAA distribution to grow into an approximately log-normal form without the use of any activation methods. Cooling gas and corona discharge can both enhance SAA growth. Cooling gas is in charge of condensation, whereas corona discharge mainly acts on coagulation. They exhibited 14.3% and 12.3% increases in mean diameter and 12.3% and 69.1% decreases in number concentration. In contrast, adding vapor led to a 1.58% decrease in mean diameter and a 9.4% increase in number concentration. Findings suggest that combining cooling gas and corona discharge to simultaneously promote coagulation and condensation and reduce SAA emission from humid flue gas is possible.
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Poluentes Atmosféricos , Aerossóis , Gases , Humanos , Tamanho da Partícula , Ácidos SulfúricosRESUMO
Slow ion kinetics of negative electrode materials is the main factor of limiting fast charge and discharge of batteries. Sluggish Na+ kinetics property leads to large electrode polarization, resulting in poor rate and cyclic performances. Herein, an electrode of ultrasmall tin nanoparticles decorated in N, S codoped carbon monolith (TCM) with exceptional high-rate capability and ultrastable cycling behavior for Na-storage is reported. The resulted TCM electrode exhibits an extremely high retention of 96% initial charge capacity after 500 cycles at a current density of 500 mA g-1 . Significantly, when the current density is elevated to an ultrahigh rate of 5000 mA g-1 , a high reversible capacity of 228 mAh g-1 after the 2000th cycle is still maintained. More importantly, the stable and fast Na-storage of TCM is investigated and understood by experimental characterizations and kinetics calculations, including interfacial ion/electron transport behavior, ion diffusion, and quantitative pseudocapacitive analysis. These investigations elucidate that the TCM shows improved ion/electron conductivity and enhanced interfacial kinetics. An entirely new perspective to deep insights into the fast ion/electron transport mechanisms revealed by interfacial kinetics of sodiation/desodiation, which contributes to the profound understanding for developing fast charging/discharging and long-term stable electrodes in sodium-ion batteries, is provided.
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PURPOSE: The aim of this study was to establish a new method of facial soft tissue analysis based on 3dMDface system and to find the different esthetic preferences of Chinese beauties from the Chinese and Indian evaluators perspective. METHODS: Three-dimensional facial images of 242 females and 168 males were evaluated and ranked by 8 Chinese and nine Indians using a 10-point visual analog scale (VAS). Total 120 subjects in 2 panels (from Chinese perspective and Indian perspective) including 30 male and 30 female faces with top 30 scores were analyzed with the "average face" method respectively. Then 17 linear measurements, 13 curve measurements and 14 ratios of 4 average faces were calculated and compared with the divine proportion. RESULTS: Distinct differences were founded based on the average face analysis. Similar total facial types were preferred by both Chinese and Indian evaluators, while Indian evaluators preferred a wider male face with a protrusive lower lip. Delicate noses with lower nose ridge but protrusive lower lips in females were more acceptable by Indian evaluators. The differences of linear measurements were limited in 2.0âmm except the facial width, lower facial width, upper facial height and forehead height while curve measurements differ distinctly as the table shows. No ratios equal to the divine proportion were founded. CONCLUSION: The 3D Average face based on stereophotogrammetry is a feasible method to analyze the facial characters and discrepancy of esthetic preferences. Chinese and Indian evaluators have some certain differences when judging beauties. Attractive faces have some certain ratios but not the divine proportion.
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Face/anatomia & histologia , Adolescente , Adulto , Povo Asiático , Beleza , Feminino , Humanos , Imageamento Tridimensional/métodos , Masculino , Fotogrametria/métodos , Escala Visual Analógica , Adulto JovemRESUMO
Phosphoinositides and their metabolizing enzymes are involved in Aß42 metabolism and Alzheimer's disease pathogenesis. In yeast and mammals, Eighty-five requiring 3 (EFR3), whose Drosophila homolog is Rolling Blackout (RBO), forms a plasma membrane-localized protein complex with phosphatidylinositol-4-kinase Type IIIα (PI4KIIIα) and a scaffold protein to tightly control the level of plasmalemmal phosphatidylinositol-4-phosphate (PI4P). Here, we report that RBO binds to Drosophila PI4KIIIα, and that in an Aß42-expressing Drosophila model, separate genetic reduction of PI4KIIIα and RBO, or pharmacological inhibition of PI4KIIIα ameliorated synaptic transmission deficit, climbing ability decline, premature death, and reduced neuronal accumulation of Aß42 Moreover, we found that RBO-PI4KIIIa downregulation increased neuronal Aß42 release and that PI4P facilitated the assembly or oligomerization of Aß42 in/on liposomes. These results indicate that RBO-PI4KIIIa downregulation facilitates neuronal Aß42 release and consequently reduces neuronal Aß42 accumulation likely via decreasing Aß42 assembly in/on plasma membrane. This study suggests the RBO-PI4KIIIα complex as a potential therapeutic target and PI4KIIIα inhibitors as drug candidates for Alzheimer's disease treatment.SIGNIFICANCE STATEMENT Phosphoinositides and their metabolizing enzymes are involved in Aß42 metabolism and Alzheimer's disease pathogenesis. Here, in an Aß42-expressing Drosophila model, we discovered and studied the beneficial role of downregulating RBO or its interacting protein PI4KIIIα-a protein that tightly controls the plasmalemmal level of PI4P-against the defects caused by Aß42 expression. Mechanistically, RBO-PI4KIIIα downregulation reduced neuronal Aß42 accumulation, and interestingly increased neuronal Aß42 release. This study suggests the RBO-PI4KIIIα complex as a novel therapeutic target, and PI4KIIIα inhibitors as new drug candidates.
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Peptídeos beta-Amiloides/metabolismo , Hidrolases de Éster Carboxílico/metabolismo , Proteínas de Drosophila/metabolismo , Drosophila/metabolismo , Antígenos de Histocompatibilidade Menor/metabolismo , Doenças do Sistema Nervoso/metabolismo , Fragmentos de Peptídeos/metabolismo , Fosfotransferases (Aceptor do Grupo Álcool)/metabolismo , Peptídeos beta-Amiloides/genética , Animais , Animais Geneticamente Modificados , Regulação para Baixo , Drosophila/genética , Doenças do Sistema Nervoso/patologia , Fragmentos de Peptídeos/genéticaRESUMO
Schisandrin B is a hepatoprotective component isolated from a traditional Chinese herb, Schisandra chinensis (Turcz.) Baill. This study determined the effect of Schisandrin B on d-galactosamine -induced liver injury and the role of heat shock proteins 27 and 70 against liver injury in mice. Acute liver injury was induced by intraperitoneal injection of d-galactosamine to mice, and Schisandrin B was given orally. The protein and gene expression of heat shock proteins 27 and 70 were detected by western blot and real-time quantitative polymerase chain reaction, respectively. Liver tissues were subjected to histological evaluation, and the activities of alanine aminotransferase and aspartate aminotransferase in the serum were measured. Pretreatment of Schisandrin B significantly attenuated d-galactosamine-induced liver injury in mice. This result was evidenced by improved alteration of histopathological hepatic necrosis and reduced alanine aminotransferase and aspartate aminotransferase activities in the serum. The hepatoprotective effect was accompanied with overexpression of heat shock proteins 27 and 70 both at the protein and mRNA levels. However, the aforementioned actions of Schisandrin B were all markedly suppressed by the heat shock protein inhibitor quercetin. Heat shock proteins 27 and 70 were involved in the protective effect of Schisandrin B against d-galactosamine-induced liver injury in mice.
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Doença Hepática Induzida por Substâncias e Drogas/tratamento farmacológico , Galactosamina/farmacologia , Proteínas de Choque Térmico HSP27/metabolismo , Proteínas de Choque Térmico HSP70/metabolismo , Lignanas/farmacologia , Compostos Policíclicos/farmacologia , Substâncias Protetoras/farmacologia , Alanina Transaminase/metabolismo , Animais , Aspartato Aminotransferases/metabolismo , Doença Hepática Induzida por Substâncias e Drogas/etiologia , Doença Hepática Induzida por Substâncias e Drogas/metabolismo , Ciclo-Octanos/farmacologia , Expressão Gênica/efeitos dos fármacos , Fígado/efeitos dos fármacos , Fígado/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos ICR , Quercetina/farmacologia , Schisandra/químicaRESUMO
We theoretically study high-order harmonic generation (HHG) and attosecond pulses from an atom irradiated synchronically by a terahertz (THz) pulse and an infrared laser pulse. For the HHG spectrum from the THz pulse alone and the combined pulse, an apparent peak-valley structure appears the platform region. Specially, for the periodic structure generated by an atom under the action of the combined pulse is originated from the interference between the electrons ionized at different instants in the laser field, which undergo many recollision and return to the core at the same time. Therefore, continuum harmonics with few chirps from the interference enhancement region can be achieved, which result in a chirp-free isolated attosecond pulse.
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This study investigated whether emotion regulation mediates or modulates the relationship of SLEs with sleep quality and potential sex differences. A total of 1447 Chinese university students completed the Adolescent Self-Rating Life Events Checklist, the Pittsburgh Sleep Quality Index, and the Emotion Regulation Questionnaire. The results indicated that both cognitive reappraisal and expressive suppression significantly mediated and moderated the negative association between SLEs and sleep quality. Additionally, sex differences were found for the mediating role of cognitive reappraisal and for the modulating roles of cognitive reappraisal and expressive suppression in the relationship between SLEs and sleep quality. Although the present cross-sectional data does not allow us to test any causal relationships, these results help clarify the underlying emotion-regulation process between SLEs and sleep in university students and highlight the importance of considering sex differences in emotion regulation.
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The residue of lincomycin in water will not only aggravate the drug resistance of bacteria but also cause damage to the human body through biological accumulation. In this work, an electrochemiluminescence (ECL) aptasensor for the detection of lincomycin was constructed based on polydimethyldiallylammonium chloride (PDDA) functionalized Ce-doped TbPO4 nanowires (PDDA-TbPO4:Ce NWs) and silver nanoparticles (Ag NPs). TbPO4:Ce NWs were used as the luminophore, and PDDA was used to functionalize the luminophore to make the surface of the luminophore positively charged. The negatively charged silver nanoparticles were combined with PDDA-TbPO4:Ce NWs by electrostatic interaction. Ag NPs accelerated the electron transfer rate and promoted the ECL efficiency, which finally increased the ECL intensity of TbPO4:Ce NWs by about 4 times. Under the optimal conditions, the detection limit of the ECL sensor was as low as 4.37 × 10-16 M, and the linear range was 1 × 10 - 15 M to 1 × 10 - 5 M, with good selectivity, stability, and repeatability. The sensor can be applied to the detection of lincomycin in water, and the recovery rate is 97.7-103.4 %, which has broad application prospects.
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Técnicas Eletroquímicas , Limite de Detecção , Lincomicina , Medições Luminescentes , Nanopartículas Metálicas , Prata , Lincomicina/análise , Prata/química , Medições Luminescentes/métodos , Nanopartículas Metálicas/química , Técnicas Eletroquímicas/métodos , Poluentes Químicos da Água/análise , Nanofios/química , Técnicas Biossensoriais/métodos , Compostos de Amônio Quaternário/químicaRESUMO
BACKGROUND: Anhedonia, a core symptom of major depressive disorder (MDD), manifests in two forms: anticipatory and consummatory, reflecting a diminished capacity to anticipate or enjoy pleasurable activities. Prior studies suggest that brain-derived neurotrophic factor (BDNF) and interleukin-10 (IL-10) may play key roles in the emergence of anhedonia in MDD. The specific relationships between these biomarkers and the two forms of anhedonia remain unclear. This study investigated the potential links between BDNF, IL-10, and both forms of anhedonia in MDD patients. METHODS: This study included 43 participants diagnosed with MDD and 58 healthy controls. It involved detailed assessments of depression and anxiety levels, anticipatory and consummatory pleasure, cognitive functions, and a broad spectrum of plasma biomarkers, such as C-reactive protein, various interleukins, and BDNF. Using partial correlation, variables related to pleasant experiences were identified. Stepwise multiple linear regression analysis was applied to pinpoint the independent predictors of anhedonia in the MDD group. RESULTS: Demographically, both groups were comparable in terms of age, sex, body mass index, educational year, and marital status. Individuals with MDD displayed markedly reduced levels of anticipatory and consummatory pleasure, higher anxiety, and depression scores compared to healthy controls. Additionally, cognitive performance was notably poorer in the MDD group. These patients also had lower plasma diamine oxidase levels. Analysis linked anhedonia to impaired delayed memory. Regression results identified IL-10 and BDNF as independent predictors of anticipatory and consummatory anhedonia, respectively. CONCLUSION: These findings demonstrate that anticipatory and consummatory anhedonia are influenced by independent factors, thereby providing critical insights into the distinct neuroimmunological mechanisms that underlie various forms of anhedonia. Clinicl Trial Registration Number: NCT03790085.
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Anedonia , Fator Neurotrófico Derivado do Encéfalo , Transtorno Depressivo Maior , Interleucina-10 , Humanos , Transtorno Depressivo Maior/sangue , Transtorno Depressivo Maior/psicologia , Masculino , Anedonia/fisiologia , Fator Neurotrófico Derivado do Encéfalo/sangue , Feminino , Adulto , Interleucina-10/sangue , Pessoa de Meia-Idade , Biomarcadores/sangue , Adulto JovemRESUMO
BACKGROUND: Schizophrenia is a prevalent mental disorder, leading to severe disability. Currently, the absence of objective biomarkers hinders effective diagnosis. This study was conducted to explore the aberrant spontaneous brain activity and investigate the potential of abnormal brain indices as diagnostic biomarkers employing machine learning methods. METHODS: A total of sixty-one schizophrenia patients and seventy demographically matched healthy controls were enrolled in this study. The static indices of resting-state functional magnetic resonance imaging (rs-fMRI) including amplitude of low frequency fluctuations (ALFF), fractional ALFF (fALFF), regional homogeneity (ReHo), and degree centrality (DC) were calculated to evaluate spontaneous brain activity. Subsequently, a sliding-window method was then used to conduct temporal dynamic analysis. The comparison of static and dynamic rs-fMRI indices between the patient and control groups was conducted using a two-sample t-test. Finally, the machine learning analysis was applied to estimate the diagnostic value of abnormal indices of brain activity. RESULTS: Schizophrenia patients exhibited a significant increase ALFF value in inferior frontal gyrus, alongside significant decreases in fALFF values observed in left postcentral gyrus and right cerebellum posterior lobe. Pervasive aberrations in ReHo indices were observed among schizophrenia patients, particularly in frontal lobe and cerebellum. A noteworthy reduction in voxel-wise concordance of dynamic indices was observed across gray matter regions encompassing the bilateral frontal, parietal, occipital, temporal, and insular cortices. The classification analysis achieved the highest values for area under curve at 0.87 and accuracy at 81.28% when applying linear support vector machine and leveraging a combination of abnormal static and dynamic indices in the specified brain regions as features. CONCLUSIONS: The static and dynamic indices of brain activity exhibited as potential neuroimaging biomarkers for the diagnosis of schizophrenia.
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Encéfalo , Aprendizado de Máquina , Imageamento por Ressonância Magnética , Esquizofrenia , Humanos , Esquizofrenia/diagnóstico por imagem , Esquizofrenia/fisiopatologia , Imageamento por Ressonância Magnética/métodos , Masculino , Feminino , Adulto , Encéfalo/diagnóstico por imagem , Encéfalo/fisiopatologia , Descanso/fisiologia , Adulto Jovem , Mapeamento Encefálico/métodos , Máquina de Vetores de SuporteRESUMO
BACKGROUND AND OBJECTIVE: Sleep disorders are a complicated and major public health concern affecting millions of individuals. Obstructive sleep apnoea (OSA) is a common but still under-recognized disease which can cause intermittent nocturnal hypercapnia. Neuropeptides play critical roles in neurotransmission, acting as transmitters or modulators. Results from recent studies have implicated several neuropeptides in sleep and breathing regulation, including orexin, neuropeptides Y and galanin. Therefore, the present study aimed to evaluate the influence of hypercapnia on these neuropeptides and their receptors in order to assess their potential role in the pathogenesis of OSA. METHODS: Fifteen C57BL/6J mice were randomly divided into three groups and exposed to moderate hypercapnia (5% CO(2) with balanced room air), or severe hypercapnia (10% CO(2) with balanced room air) or room air for 3 h (9:00-12:00 h), respectively. Immediately following exposure the brainstem and hypothalamus were excised for real-time reverse transcription polymerase chain reaction and western blot analyses. RESULTS: In the hypothalamus gene expression including galanin, orexin and neuropeptide Y receptor 1 (NPYR1) was downregulated by hypercapnia. However, protein and mRNA levels of orexin-A receptor were upregulated by severe hypercapnia. In the brainstem only NPYR1 mRNA expression was decreased in moderate hypercapnia compared with that in severe hypercapnia. CONCLUSIONS: These findings suggest that hypercapnia can affect these neuropeptides and their receptors, especially the orexin and orexin-A receptor. The potential relationships between these peptides and OSA are worthy of further investigation.