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1.
Bipolar Disord ; 2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38647010

RESUMO

BACKGROUND: Gut microbial disturbance has been widely confirmed in mood disorders. However, little is known about whether gut microbial characteristics can distinguish major depressive disorder (MDD), bipolar depression (BP-D), and bipolar mania (BP-M). METHODS: This was a prospective case-control study. The composition of gut microbiota was profiled using 16S ribosomal RNA (rRNA) gene sequencing of fecal samples and compared between healthy controls (HC; n = 46), MDD (n = 51), BP-D (n = 44), and patients with BP-M (n = 45). RESULTS: Gut microbial compositions were remarkably changed in the patients with MDD, BP-D, and BP-M. Compared to HC, distinct gut microbiome signatures were found in MDD, BP-D, and BP-M, and some gut microbial changes were overlapping between the three mood disorders. Furthermore, we identified a signature of 7 operational taxonomic units (OUT; Prevotellaceae-related OUT22, Prevotellaceae-related OUT31, Prevotellaceae-related OTU770, Ruminococcaceae-related OUT70, Bacteroidaceae-related OTU1536, Propionibacteriaceae-related OTU97, Acidaminococcaceae-related OTU34) that can distinguish patients with MDD from those with BP-D, BP-M, or HC, with area under the curve (AUC) values ranging from 0.910 to 0.996. CONCLUSION: Our results provide the clinical rationale for the discriminative diagnosis of MDD, BP-D, and BP-M by characteristic gut microbial features.

2.
Brain Topogr ; 37(2): 232-242, 2024 03.
Artigo em Inglês | MEDLINE | ID: mdl-37548801

RESUMO

Microstate analysis is a promising technique for analyzing high-density electroencephalographic data, but there are multiple questions about methodological best practices. Between and within individuals, microstates can differ both in terms of characteristic topographies and temporal dynamics, which leads to analytic challenges as the measurement of microstate dynamics is dependent on assumptions about their topographies. Here we focus on the analysis of group differences, using simulations seeded on real data from healthy control subjects to compare approaches that derive separate sets of maps within subgroups versus a single set of maps applied uniformly to the entire dataset. In the absence of true group differences in either microstate maps or temporal metrics, we found that using separate subgroup maps resulted in substantially inflated type I error rates. On the other hand, when groups truly differed in their microstate maps, analyses based on a single set of maps confounded topographic effects with differences in other derived metrics. We propose an approach to alleviate both classes of bias, based on a paired analysis of all subgroup maps. We illustrate the qualitative and quantitative impact of these issues in real data by comparing waking versus non-rapid eye movement sleep microstates. Overall, our results suggest that even subtle chance differences in microstate topography can have profound effects on derived microstate metrics and that future studies using microstate analysis should take steps to mitigate this large source of error.


Assuntos
Encéfalo , Eletroencefalografia , Humanos , Eletroencefalografia/métodos , Voluntários Saudáveis , Probabilidade , Extremidade Superior
3.
BMC Psychiatry ; 24(1): 433, 2024 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-38858652

RESUMO

BACKGROUND: Objective and quantifiable markers are crucial for developing novel therapeutics for mental disorders by 1) stratifying clinically similar patients with different underlying neurobiological deficits and 2) objectively tracking disease trajectory and treatment response. Schizophrenia is often confounded with other psychiatric disorders, especially bipolar disorder, if based on cross-sectional symptoms. Awake and sleep EEG have shown promise in identifying neurophysiological differences as biomarkers for schizophrenia. However, most previous studies, while useful, were conducted in European and American populations, had small sample sizes, and utilized varying analytic methods, limiting comprehensive analyses or generalizability to diverse human populations. Furthermore, the extent to which wake and sleep neurophysiology metrics correlate with each other and with symptom severity or cognitive impairment remains unresolved. Moreover, how these neurophysiological markers compare across psychiatric conditions is not well characterized. The utility of biomarkers in clinical trials and practice would be significantly advanced by well-powered transdiagnostic studies. The Global Research Initiative on the Neurophysiology of Schizophrenia (GRINS) project aims to address these questions through a large, multi-center cohort study involving East Asian populations. To promote transparency and reproducibility, we describe the protocol for the GRINS project. METHODS: The research procedure consists of an initial screening interview followed by three subsequent sessions: an introductory interview, an evaluation visit, and an overnight neurophysiological recording session. Data from multiple domains, including demographic and clinical characteristics, behavioral performance (cognitive tasks, motor sequence tasks), and neurophysiological metrics (both awake and sleep electroencephalography), are collected by research groups specialized in each domain. CONCLUSION: Pilot results from the GRINS project demonstrate the feasibility of this study protocol and highlight the importance of such research, as well as its potential to study a broader range of patients with psychiatric conditions. Through GRINS, we are generating a valuable dataset across multiple domains to identify neurophysiological markers of schizophrenia individually and in combination. By applying this protocol to related mental disorders often confounded with each other, we can gather information that offers insight into the neurophysiological characteristics and underlying mechanisms of these severe conditions, informing objective diagnosis, stratification for clinical research, and ultimately, the development of better-targeted treatment matching in the clinic.


Assuntos
Eletroencefalografia , Esquizofrenia , Adulto , Feminino , Humanos , Masculino , Biomarcadores , Estudos de Coortes , Eletroencefalografia/métodos , Neurofisiologia/métodos , Projetos de Pesquisa , Esquizofrenia/fisiopatologia , Esquizofrenia/diagnóstico , Sono/fisiologia , Estudos Transversais , Pessoa de Meia-Idade , Idoso
4.
Acta Neuropsychiatr ; 35(6): 362-371, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37605898

RESUMO

BACKGROUND: Suicide prevention for major depressive disorder (MDD) is a worldwide challenge, especially for suicide attempt (SA). Viewing suicide as a state rather than a lifetime event provided new perspectives on suicide research. OBJECTIVE: This study aimed to verify and complement SAs biomarkers of MDD with a recent SA sample. METHODS: This study included 189 participants (60 healthy controls; 47 MDD patients with non-suicide (MDD-NSs), 40 MDD patients with suicide ideation (MDD-SIs) and 42 MDD patients with SA (MDD-SAs)). MDD patients with an acute SA time was determined to be within 1 week since the last SA. SUICIDALITY Part in MINI was applied to evaluate suicidality. Absolute powers in 14 frequency bands were extracted from subject's resting-state electroencephalography data and compared within four groups. The relationship among suicidality, the number of SA and powers in significant frequency bands were investigated. RESULTS: MDD-SIs had increased powers in delta, theta, alpha and beta band on the right frontocentral channels compared to MDD-NSs, while MDD-SAs had decreased powers in delta, beta and gamma bands on widely the right frontocentral and parietooccipital channels compared to MDD-SIs. Beta 1 power was the lowest in MDD-SAs and was modulated by the number of SA. The correlation between suicidality and beta 1 power was negative in MDD-SAs and positive in MDD-SIs. CONCLUSION: Reduced beta 1 (12-15 Hz) power could be essential in promoting suicidal behaviour in MDD. Research on recent SA samples contributes to a better understanding of suicide mechanisms and preventing suicidal behaviour in MDD.


Assuntos
Transtorno Depressivo Maior , Humanos , Ideação Suicida , Tentativa de Suicídio , Prevenção do Suicídio , Eletroencefalografia
5.
Adicciones ; 0(0): 1342, 2020 Feb 06.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-32100045

RESUMO

Cognitive dysfunction may be a critical aspect of addictive disorders. This study aimed to examine whether individuals with Internet gaming disorder (IGD) have similar neurocognitive dysfunctions and social cognitive impairments as methamphetamine dependence (MD) patients. The participants included 30 individuals with IGD, 30 MD patients and 30 normal controls (NCs). All participants completed the digit span task, Iowa gambling task (IGT), WCST and the Interpersonal Perception Task-15 (IPT-15). The results showed that the IGD and MD groups had lower forwards and backwards scores, choices of advantageous minus disadvantageous decks, mean amount of money earned, number of categories completed, percentage of conceptual level responses, and IPT-15 total and factor scores compared with the NC group. Forwards and backwards scores, number of categories completed, percentage of conceptual level responses, choices from advantageous minus disadvantageous decks and mean amount of money earned were lower in the IGD group than in the MD group. The number of cards chosen from decks A, B, C, and D, total response errors, perseverative errors and failure to maintain set were higher in the IGD and MD groups than in NCs. Total response errors, perseverative errors and failure to maintain set were higher in the IGD than the MD group. The results revealed that neurocognitive deficits and social cognitive dysfunction in IGD are similar to those in MD. From a cognitive perspective, these results supported IGD as an addictive spectrum disorder and might lead to a better assessment of therapeutic efficacy.


Las disfunciones cognitivas pueden ser una parte esencial de trastornos de adicción. El objetivo de este estudio fue examinar si las personas con trastorno de juego en Internet (TJI) tienen deficiencias cognitivas y disfunciones sociocognitivas similares a los pacientes con dependencia de la metanfetamina (DM). Los participantes incluyeron 30 personas con TJI, 30 pacientes con DM, y 30 Controles Normales (CN). Todos los participantes completaron la tarea de dígitos, Iowa gambling task (IGT), WCST e Interpersonal Perception Task-15 (IPT-15). Los resultados mostraron que los grupos de TJI y DM obtuvieron puntuaciones más bajas en dígitos directos e inversos, elecciones de barajas favorables menos barajas desfavorables, cuantía media de ganancia monetaria, número de categorías completadas, porcentaje de respuestas a nivel conceptual, y puntuaciones totales y factoriales del IPT-15, comparado con el grupo CN. Las puntuaciones en dígitos directos e inversos, número de categorías completadas, porcentaje de respuestas a nivel conceptual, elecciones de barajas favorables menos barajas desfavorables, y cuantía media de ganancia monetaria eran más bajas en el grupo TJI que en el grupo DM. El número de cartas elegidas de las barajas A, B, C, y D, total de respuestas erróneas, errores perseverativos, e incapacidad para mantenimiento de sets eran más elevados en los grupos TJI y DM que en el grupo CN. El total de respuestas erróneas, errores perseverativos, e incapacidad para mantener los sets eran más elevados en el grupo TJI que en el grupo DM. Los resultados mostraron que las deficiencias neurocognitivas y disfunciones sociocognitivas son similares en los grupos TJI y DM. Desde una perspectiva cognitiva, dichos resultados apoyan la hipótesis del TJI como trastorno del espectro de las adicciones, y podría llevar a una mejor valoración de la eficacia del tratamiento.

6.
ACS Omega ; 9(11): 13239-13251, 2024 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-38524443

RESUMO

Refined asphalt was prepared by solvent extraction sedimentation based on the response surface design, using washing oil and kerosene as solvents and the coal tar pitch as raw materials. The mathematical models of the refined asphalt yield, quinoline insoluble (QI) content, ash content, solvent-to-oil ratio, aromatic-to-aliphatic hydrocarbon ratio, extraction temperature, and sedimentation time were proposed, analyzing the influence of each factor and their interactions on the response values. Therefore, the optimal combination of preparation process parameters and better operation window was obtained by optimizing the experiment. Meanwhile, refined asphalt with high QI content and low QI content was selected as raw material, and the needle coke was prepared through the process of carbonization and calcination. The influence of QI content on the composition and the structure of green coke and needle coke was investigated by X-ray diffraction (XRD), Raman spectra, and polarizing microscopy characterizations. The results showed that the solvent-to-oil ratio is 1.2, aromatic-to-aliphatic hydrocarbon ratio is 1.1, sedimentation time is 2 h, and extraction temperature is 110 °C, resulting in the yield of refined asphalt being 76%, QI content being less than 0.1%, and ash content being less than 0.05%, which meets the requirement of the high-quality needle coke. Otherwise, refined asphalt with lower QI content easily generates a mesophase with more fibers and a large structure in the thermal conversion process, and the corresponding green coke and needle coke have a relatively regular carbon microcrystalline structure.

7.
Int J Biol Macromol ; 263(Pt 1): 130178, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38368981

RESUMO

Network optimization is vital for the polysaccharide based hydrogels with multiple crosslinks. In this study, we developed a 'two-step' strategy to activate synergistic effect of chemical and physical crosslinks using a poly (vinyl alcohol) (PVA)/bacterial cellulose (BC) hydrogel as a template. The BC nanofibers, on the one hand, acted as nucleating agents, participating in the crystallization of PVA, and on the other hand, were also involved in the formation of boronic ester bond, anchored with the PVA chains via chemical bonding. Therefore, the existence of BC nanofibers, as 'bridge', linked the crystalline regions and amorphous parts of PVA together, associating the two characteristic crosslinks, which was conducive to load transfer. The mechanical properties of resultant hydrogels, including the tensile elongation and strength, as well as fracture toughness, were significantly improved. Moreover, the dually cross-linked hydrogels possessed ionic conductivity, which was sensitive to the tensile deformation and environmental temperature. This study clarifies a unique role of BC nanofibers in hydrogels, and proposes an effective approach to construct multiple networks in the nanocellulose reinforced PVA hydrogels.


Assuntos
Celulose , Nanofibras , Álcool de Polivinil/química , Hidrogéis/química , Resistência à Tração
8.
J Affect Disord ; 351: 843-852, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38341154

RESUMO

BACKGROUND: The causal relationship between different hypothyroidism subtypes and the risk of major depression (MD) is yet to be fully elucidated. This study aimed to determine if there's a causal relationship between various hypothyroidism subtypes (and related factors) and the risk of MD. METHODS: This genetic association study utilized a two-sample Mendelian Randomization (MR) approach to explore the causal relationships between various hypothyroidism subtypes and MD risk. Genome-Wide Association Study (GWAS) summary statistics were obtained from the FinnGen and the UK Biobank. Instrumental variables (IVs) were chosen based on single nucleotide polymorphisms (SNPs). RESULTS: Among the analyzed hypothyroidism subtypes and related factors, "Hypothyroidism, strict autoimmune" (HTCBSA) and "Hypothyroidism, levothyroxin purchases" (HT/LP) demonstrated a statistically significant positive causal relationship with MD, with odds ratios of 1.020 (95 % CI: 1.004-1.037) and 1.022 (95 % CI: 1.005-1.040), respectively. The sensitivity analysis supported the robustness of these findings, showing no significant horizontal pleiotropy and confirming the stability of results when individual SNPs were removed. "Congenital iodine-deficiency syndrome/hypothyroidism" (CIDS/HT), "Postinfectious hypothyroidism" (PHT), "Hypothyroidism due to medicaments and other exogenous substances" (HDTDM and OES), "Thyroid Stimulating Hormone" (TSH), "Thyrotropin-releasing hormone" (THRH), and "Hypothyroidism, strict autoimmune, 3 medication purchases required" (HTCBSA/3MPR) showed no significant causal relationship with MD. LIMITATIONS: The study population was limited to individuals of European ancestry, and there may be certain genetic differences between different ethnic groups. CONCLUSIONS: This MR study suggests a potential causal relationship between certain hypothyroidism subtypes (specifically HTCBSA and HT/LP) and an increased risk of MD.


Assuntos
Transtorno Depressivo Maior , Hipotireoidismo , Humanos , Transtorno Depressivo Maior/genética , Depressão , Estudo de Associação Genômica Ampla , Análise da Randomização Mendeliana , Hipotireoidismo/genética , Tiroxina
9.
Int J Biol Macromol ; 277(Pt 3): 134286, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39217036

RESUMO

As the derivative of konjac glucomannan (KGM), carboxymethyl konjac glucomannan (CMK) has attracted increasing attention in the polysaccharide hydrogel fields with the aim of improving the performance related to drug delivery and release. In this study, we prepared a CMK-based hydrogel with dual characteristic crosslinks, and unlocked new applications of this type of hydrogel in soft sensor fields. CMK and poly (vinyl alcohol) were used as substrates, and physical crosslinks were constructed via the freeze-thawing treatments and covalent crosslinks were built via the boronic ester bonding. As-prepared hydrogel possessed significantly improved mechanical performance because the boronic ester bonding, on the one hand, well associated the two kinds of polymer chains, and on the other hand, played the role of 'sacrificial crosslinks'. Furthermore, the occurrence of dynamic boronic ester bonding gave the hydrogel strain- and temperature-sensitive ionic conductivity, and therefore, the hydrogels could be used to identify human motions and as-resulted environmental temperature alterations, and worked well in various scenarios. This work activates new application of CMK in the multimodal sensing field, and also proposes an intriguing way of building multiple crosslinks in the KGM derivative-based hydrogels.


Assuntos
Ácidos Borônicos , Hidrogéis , Mananas , Mananas/química , Hidrogéis/química , Ácidos Borônicos/química , Ésteres/química , Humanos , Álcool de Polivinil/química , Temperatura , Reagentes de Ligações Cruzadas/química
10.
Biol Psychiatry Glob Open Sci ; 4(6): 100371, 2024 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-39296796

RESUMO

Background: Aberrant functional connectivity is a hallmark of schizophrenia. The precise nature and mechanism of dysconnectivity in schizophrenia remains unclear, but evidence suggests that dysconnectivity is different in wake versus sleep. Microstate analysis uses electroencephalography (EEG) to investigate large-scale patterns of coordinated brain activity by clustering EEG data into a small set of recurring spatial patterns, or microstates. We hypothesized that this technique would allow us to probe connectivity between brain networks at a fine temporal resolution and uncover previously unknown sleep-specific dysconnectivity. Methods: We studied microstates during sleep in patients with schizophrenia by analyzing high-density EEG sleep data from 114 patients with schizophrenia and 79 control participants. We used a polarity-insensitive k-means analysis to extract a set of 6 microstate topographies. Results: These 6 states included 4 widely reported canonical microstates. In patients and control participants, falling asleep was characterized by a shift from microstates A, B, and C to microstates D, E, and F. Microstate F was decreased in patients during wake, and microstate E was decreased in patients during sleep. The complexity of microstate transitions was greater in patients than control participants during wake, but this reversed during sleep. Conclusions: Our findings reveal behavioral state-dependent patterns of cortical dysconnectivity in schizophrenia. Furthermore, these findings are largely unrelated to previous sleep-related EEG markers of schizophrenia such as decreased sleep spindles. Therefore, these findings are driven by previously undescribed sleep-related pathology in schizophrenia.


EEG microstates are stereotyped patterns of scalp voltage topography that provide information about brain activity at millisecond-level temporal resolution. We used this method to study brain activity in schizophrenia during sleep and wake. We found state-dependent case-control differences in EEG microstates that were unrelated to the results of classic EEG analyses. These differences reflect aberrant neural functioning during sleep in patients with schizophrenia.

11.
Braz J Psychiatry ; 2024 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-38870426

RESUMO

BACKGROUND: Panic disorder (PD) is a common disabling condition characterized by recurrent panic attacks. Emotional and behavioral impairments are associated with functional connectivity (FC) and network abnormalities. We used the whole brain FC, modular networks, and graph-theory analysis to investigate extensive network profiles in PD. METHOD: The functional MRI data from 82 PD and 97 controls were included. Intrinsic FC between each pair of 160 regions, 6 intra-networks, and 15 inter-networks were analyzed. The topological properties were explored. RESULTS: PD patients showed altered FCs within the right insula, between frontal cortex-posterior cingulate cortex (PCC), frontal cortex-cerebellum, and PCC-occipital cortex (corrected P values < 0.001). Lower connections within the Sensorimotor Network (SMN) and SMN-Occipital Network (OCN) were detected (P values < 0.05). Various decreased global and local network features were found in PD (P values < 0.05). In addition, significant correlations were found between PD symptoms and nodal efficiency (Ne) in the insula (r = -0.273, P = 0.016), and the FC of the intra-insula (r = -0.226, P = 0.041). CONCLUSIONS: PD patients present with abnormal functional brain networks, especially the decreased FC and Ne within insula, suggesting that dysfunction of information integration plays an important role in PD.

12.
CNS Neurosci Ther ; 30(8): e14923, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39154365

RESUMO

BACKGROUND: The intricate pathophysiological mechanisms of major depressive disorder (MDD) necessitate the development of comprehensive early indicators that reflect the complex interplay of emotional, physical, and cognitive factors. Despite its potential to fulfill these criteria, interoception remains underexplored in MDD. This study aimed to evaluate the potential of interoception in transforming MDD's clinical practices by examining interoception deficits across various MDD stages and analyzing their complex associations with the spectrum of depressive symptoms. METHODS: This study included 431 healthy individuals, 206 subclinical depression individuals, and 483 MDD patients. Depressive symptoms and interoception function were assessed using the PHQ-9 and MAIA-2, respectively. RESULTS: Interoception dysfunction occurred in the preclinical phase of MDD and further impaired in the clinical stage. Antidepressant therapies showed limited efficacy in improving interoception and might damage some dimensions. Interoceptive dimensions might predict depressive symptoms, primarily enhancing negative thinking patterns. The predictive model based on interoception was built with random split verification and demonstrated good discrimination and predictive performance in identifying MDD. CONCLUSIONS: Early alterations in the preclinical stage, multivariate associations with depressive symptoms, and good discrimination and predictive performance highlight the importance of interoception in MDD management, pointing to a paradigm shift in diagnostic and therapeutic approaches.


Assuntos
Transtorno Depressivo Maior , Interocepção , Humanos , Transtorno Depressivo Maior/psicologia , Transtorno Depressivo Maior/fisiopatologia , Transtorno Depressivo Maior/tratamento farmacológico , Interocepção/fisiologia , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Adulto Jovem
13.
Sleep ; 2024 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-39297495

RESUMO

Multiple facets of sleep neurophysiology, including electroencephalography (EEG) metrics such as non-rapid eye movement (NREM) spindles and slow oscillations, are altered in individuals with schizophrenia (SCZ). However, beyond group-level analyses, the extent to which NREM deficits vary among patients is unclear, as are their relationships to other sources of heterogeneity including clinical factors, ageing, cognitive profiles and medication regimens. Using newly collected high-density sleep EEG data on 103 individuals with SCZ and 68 controls, we first sought to replicate our previously reported group-level differences between patients and controls (original N=130) during N2 stage. Then in the combined sample (N=301 including 175 patients), we characterized patient-to-patient variability. We replicated all group-level mean differences and confirmed the high accuracy of our predictive model (AUC=0.93 for diagnosis). Compared to controls, patients showed significantly increased between-individual variability across many (26%) sleep metrics. Although multiple clinical and cognitive factors were associated with NREM metrics, collectively they did not account for much of the general increase in patient-to-patient variability. Medication regimen was a greater contributor to variability. Some sleep metrics including fast spindle density showed exaggerated age-related effects in SCZ, and patients exhibited older predicted biological ages based on the sleep EEG; further, among patients, certain medications exacerbated these effects, in particular olanzapine. Collectively, our results point to a spectrum of N2 sleep deficits among SCZ patients that can be measured objectively and at scale, with relevance to both the etiological heterogeneity of SCZ as well as potential iatrogenic effects of antipsychotic medication.

14.
ACS Appl Mater Interfaces ; 15(12): 16097-16108, 2023 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-36924131

RESUMO

Bilayer hydrogel-based actuators have attracted much interest because inhomogeneous structures are easily constructed in hydrogels. We used three kinds of polysaccharides, including anionic carboxymethyl cellulose (CMC), cationic chitosan (CS), and amphoteric carboxymethyl chitosan (CMCS), as both structure-constructing units and actuation-controlling units in this work to fabricate physically crosslinked poly(vinyl alcohol) bilayer hydrogels. The spatial heterogeneity was tuned by changing the types and concentrations of polysaccharides in different layers, to regulate pH- and humidity-driven actions of bilayer hydrogels. Based on the distortion of the ionic channel during the humidity-motivated deformation of bilayer hydrogels, a two-in-one flexible device integrating a humidity-driven actuator and humidity-responsive sensor was then developed, which could detect the alterations of environmental humidity in real time. Moreover, good tensile toughness and interfacial bonding as well as the strain-resistance effect endowed the bilayer hydrogels with the capability of identifying human motion as a strain sensor, unlocking more application scenarios. This work provides an overall insight into the heterogeneity regulation of bilayer hydrogels using polysaccharides as stimulus-responsive units and also proposes an interesting strategy of manufacturing hydrogel-based flexible devices with both actuating and sensing capabilities.

15.
Int J Biol Macromol ; 239: 124372, 2023 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-37030462

RESUMO

Using polysaccharide nanocrystals such as chitin nanocrystals (ChNCs) as nanofiller for biodegradable aliphatic polymers is an attractive way of developing all-degradable nanocomposites. Crystallization study is vital for well regulating final performance of these type polymeric nanocomposites. In this work, ChNCs were incorporated with the poly(l-lactide)/poly(d-lactide) blends and as-obtained nanocomposites were used as target samples for the study. The results showed that ChNCs acted as nucleating agent, promoting the formation of stereocomplex (SC) crystallites and accelerating overall crystallization kinetics as a result. Therefore, the nanocomposites possessed higher SC crystallization temperatures and lower apparent activation energy as compared to the blend. However, the formation of homocrystallites (HC) was dominated by nucleation effect of SC crystallites and accordingly, the fraction of SC crystallites reduced more or less in the presence of ChNCs, despite the nanocomposites possessed higher rate of HC crystallization. This study also provided valuable information on accessing more applications of ChNCs to be used as SC nucleator for polylactide.


Assuntos
Quitina , Nanopartículas , Estereoisomerismo , Poliésteres/química , Polímeros/química
16.
Materials (Basel) ; 16(19)2023 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-37834700

RESUMO

The copolymer ethylene-octene (POE) has good aging resistance and is an inexpensive asphalt additive compared to the styrene-butadiene-styrene copolymer (SBS). However, POE is easy to segregate in asphalt during storage at high temperatures. Grafting glycidyl methacrylate (GMA) onto the molecular backbone of POE (i.e., POE-g-GMA) may solve this problem, for the epoxy groups in GMA can react with the active groups in asphalt. Asphalt modified with linear and crosslinked POE-g-GMA were prepared, and the hot storage stability, physical properties and thermal oxidation aging properties were discussed in detail. The results show that linear and low-degree crosslinked POE-g-GMA-modified asphalts are storage-stable at high temperatures via measurements of the difference in softening points and small-angle X-ray scattering (SAXS) characterizations from macro and micro perspectives. The difference in softening points (ΔSP) between the upper and lower ends is no more than 3.5 °C for modified asphalts after 48 h of being in an oven at 163 °C. More importantly, the crosslinking modification of POE-g-GMA can further increase the softening point and reduce the penetration as well as rheological properties via conventional physical property, dynamic shear rheometer (DSR) and multiple-stress creep recovery (MSCR) tests. Furthermore, asphalt modified with crosslinked POE-g-GMA reveals better aging resistance via measurements of the performance retention rate and electron paramagnetic resonance (EPR) characterizations after a rolling thin film oven test (RTFOT). This work may provide further guidelines for the application of polymers in asphalt.

17.
Neuropsychiatr Dis Treat ; 19: 117-131, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36660318

RESUMO

Purpose: Deficits in facial emotional intensity recognition have been associated with social cognition in patients with major depression. The study examined multiple event-related potential (ERP) components in patients with major depression and investigated the relationships between ERPs, social cognition, and clinical features. Participants and Methods: Thirty-one patients met DSM-IV diagnosis of depression and 31 healthy participants completed the emotion intensity recognition task (EIRT), while ERPs were recorded. Data on ERP components (P100, N170, P200, and P300) were analyzed. Results: The behavioral results showed that patients with major depression performed worse on EIRT, including all six categories of emotions (sadness, disgust, happiness, surprise, anger, and fear), compared to healthy participants. The ERP results showed that patients with major depression exhibited higher P100 amplitudes for sad and happy faces than healthy participants; P300 amplitudes induced by sad and surprise faces were also higher than in healthy participants, mainly in the central and temporal lobes. A positive correlation was found between sadness intensity scores and P100 amplitudes in patients with major depression. Conclusion: Patients with major depression are biased in their identification of facial expressions indicating emotional intensity. Specifically, they have emotional biases in the early and late stages of cognitive processing, mainly in the form of sensitivity to sad stimuli. It may lead to a persistent rumination of sadness that is detrimental to the remission of depression. Additionally, patients with major depression devote different amounts of cognitive resources for different intensities of sad faces during the preconscious stage of cognitive processing. The more intense their perception of sadness, the more cognitive resources they devote. Therefore, the assessment of the intensity of facial expressions is an important research topic, with clinical implications on social cognitive function in patients with major depression.

18.
Neuropsychiatr Dis Treat ; 19: 2807-2816, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38144699

RESUMO

Background: Depression is a heritable brain disorder. Laminin genes were recently identified to affect the brain's overall thickness through neurogenesis, differentiation, and migration in depression. This study aims to explore the effects of the LAMA2's single nucleotide polymorphisms (SNP), a subunit gene of laminin, on the detected brain regions of patients with major depressive disorder (MDD). Methods: The study included 89 patients with MDD and 60 healthy controls with T1-weighted structural magnetic resonance imaging and blood samples for genotyping. The interactions between LAMA2 gene SNPs and diagnosis as well as duration of illness (DOI) were explored on brain measures controlled for age, gender, and site. Results: The right transverse temporal gyrus and right parahippocampal gyrus showed reduced thickness in MDD. Almost all seven LAMA2 SNPs showed significant interactions with diagnosis on both gyrus (corrected p < 0.05 or trending). In MDD, rs6569604, rs2229848, rs2229849, rs2229850, and rs2784895 interacted with DOI on the right transverse temporal gyrus (corrected p < 0.05), but not the right parahippocampal gyrus. Conclusion: The thickness of the right transverse temporal gyrus in patients with MDD may be affected by LAMA2 gene and DOI.

19.
Asian J Psychiatr ; 88: 103744, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37619416

RESUMO

BACKGROUND: Childhood trauma, low social support, and alexithymia are recognized as risk factors for major depressive disorder (MDD). However, the mechanisms of risk factors, symptoms, and corresponding structural brain abnormalities in MDD are not fully understood. Structural equation modeling (SEM) has advantages in studying multivariate interrelationships. We aim to illustrate their relationships using SEM. METHODS: 313 MDD patients (213 female; mean age 42.49 years) underwent magnetic resonance imaging and completed assessments. We integrated childhood trauma, alexithymia, social support, anhedonia, depression, anxiety, suicidal ideation and cortical thickness into a multivariate SEM. RESULTS: We first established the risk factors-clinical phenotype SEM with an adequate fit. Cortical thickness results show a negative correlation of childhood trauma with the left middle temporal gyrus (MTG) (p = 0.012), and social support was negatively correlated with the left posterior cingulate cortex (PCC) (p < 0.001). The final good fit SEM (χ2 = 32.92, df = 21, χ2/df = 1.57, CFI = 0.962, GFI = 0.978, RMSEA = 0.043) suggested two pathways, with left PCC thickness mediating the relationship between social support and suicidal ideation, and left MTG thickness mediating between childhood trauma and anhedonia/anxiety. CONCLUSION: Our findings provide evidence for the impact of risk factor variables on the brain structure and clinical phenotype of MDD patients. Insufficient social support and childhood trauma might lead to corresponding cortical abnormalities in PCC and MTG, affecting the patient's mood and suicidal ideation. Future interventions should aim at these nodes.

20.
Psychiatry Res ; 326: 115301, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37390600

RESUMO

An unseen wave of vast infection was detected in China in December 2022, and healthcare workers faced inevitable challenges and heavy stress. We aimed to present a dynamic mental health map and, most importantly, provide a timely report of the current situation in healthcare workers. The current study conducted four national cross-sectional online surveys from February and March 2020, Apr 2022, and Jan 2023. The Psychosomatic Symptom Scale (PSSS) and Perceived Stress Scale-10 (PSS-10) were used to assess psychosomatic symptoms and perceived stress. Fourteen thousand nine hundred forty-five participants (8578 healthcare workers and 6367 others) participated in the surveys. The prevalence of psychosomatic syndrome, reflected by PSSS, was 19.3% (Wave1), 22.9% (Wave2), 36.4% (Wave3), and 60.7% (Wave4) among healthcare workers, compared to 24.0% (Wave1), 35.7% (Wave2), 34.2% (Wave3) and 50.5% (Wave4) among the others. In addition, healthcare workers exhibited lower PSSS total scores at the beginning but higher in later waves. Despite their infection status, they now suffer from more severe psychosomatic symptoms than the rest of society. Our findings suggest that healthcare workers in China have now experienced severe psychosomatic symptoms and tremendous stress. Therefore, there is an urgent need to utilize social support for them.


Assuntos
COVID-19 , Humanos , COVID-19/epidemiologia , Estudos Transversais , Pandemias , Pessoal de Saúde/psicologia , Estresse Psicológico/epidemiologia , China/epidemiologia
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