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The abundance of distractors in the world poses a major challenge to our brain's limited processing capacity, but little is known about how selective attention modulates stimulus representations in the brain to reduce interference and support durable target memory. Here, we collected functional magnetic resonance imaging (fMRI) data in a selective attention task in which target and distractor pictures of different visual categories were simultaneously presented. Participants were asked to selectively process the target according to the effective cue, either before the encoding period (i.e., perceptual attention) or the maintenance period (i.e., reflective attention). On the next day, participants were asked to perform a memory recognition task in the scanner in which the targets, distractors, and novel items were presented in a pseudorandom order. Behavioral results showed that perceptual attention was better at enhancing target memory and reducing distractor memory than reflective attention, although the overall memory capacity (memory for both target and distractor) was comparable. Using multiple-voxel pattern analysis of the neural data, we found more robust target representation and weaker distractor representation in working memory for perceptual attention than for reflective attention. Interestingly, perceptual attention partially shifted the regions involved in maintaining the target representation from the visual cortex to the parietal cortex. Furthermore, the targets and distractors simultaneously presented in the perceptual attention condition showed reduced pattern similarity in the parietal cortex during retrieval compared to items not presented together. This neural pattern repulsion positively correlated with individuals' recognition of both targets and distractors. These results emphasize the critical role of selective attention in transforming memory representations to reduce interference and improve long-term memory performance.
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Atenção , Imageamento por Ressonância Magnética , Memória de Longo Prazo , Memória de Curto Prazo , Lobo Parietal , Humanos , Atenção/fisiologia , Lobo Parietal/fisiologia , Masculino , Memória de Curto Prazo/fisiologia , Feminino , Memória de Longo Prazo/fisiologia , Adulto , Adulto Jovem , Objetivos , Mapeamento Encefálico , Estimulação Luminosa/métodos , Percepção Visual/fisiologiaRESUMO
One new canthinone glycoside (1), together with six known compounds (2-7) including three lignans (2-4), two coumarins (5-6) and one phenol (7) was isolated from the root barks of Ailanthus altissima. The structure of new compound 1 was established by the interpretation of UV, IR, MS and NMR data, while its absolute configuration was determined by acid hydrolysis and GIAO NMR calculations with DP4+ probability analysis. The inhibitory effects of all compounds on Nitric oxide (NO) production were investigated in lipopolysaccharide (LPS)-induced RAW 264.7 cells. Results showed that compounds 2 and 5 displayed NO production inhibitory activity with IC50 values of 30.1 and 15.3 µM, respectively.
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After learning semantically related words, some people are more likely than others to incorrectly recall unstudied but semantically related lures (i.e., Deese-Roediger-McDermott [DRM] false recall). Previous studies have suggested that neural activity in subcortical regions (e.g., the caudate) is involved in false memory, and that there may be sex differences in the neural basis of false memory. However, sex-specific associations between subcortical volumes and false memory are not well understood. This study investigated whether sex modulates the associations between subcortical volumes and DRM false recall in 400 healthy college students. Volumes of subcortical regions including the caudate, accumbens, amygdala, hippocampus, pallidum, putamen and thalamus were obtained from structural magnetic resonance images and measured using FreeSurfer. The results showed that males had lower true and false recall but larger subcortical volumes than females. Interestingly, higher false recall was associated with a larger caudate in males, but not in females. This association was significant after controlling for age and intracranial volume. This study provides new evidence on the neural basis of false recall. It suggests that the caudate plays a role in false recall in young men, and that future studies of the neural correlates of false memory should consider sex differences.
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Elucidating the neural mechanisms of general cognitive ability (GCA) is an important mission of cognitive neuroscience. Recent large-sample cohort studies measured GCA through multiple cognitive tasks and explored its neural basis, but they did not investigate how task number, factor models, and neural data type affect the estimation of GCA and its neural correlates. To address these issues, we tested 1,605 Chinese young adults with 19 cognitive tasks and Raven's Advanced Progressive Matrices (RAPM) and collected resting state and n-back task fMRI data from a subsample of 683 individuals. Results showed that GCA could be reliably estimated by multiple tasks. Increasing task number enhances both reliability and validity of GCA estimates and reliably strengthens their correlations with brain data. The Spearman model and hierarchical bifactor model yield similar GCA estimates. The bifactor model has better model fit and stronger correlation with RAPM but explains less variance and shows weaker correlations with brain data than does the Spearman model. Notably, the n-back task-based functional connectivity patterns outperform resting-state fMRI in predicting GCA. These results suggest that GCA derived from a multitude of cognitive tasks serves as a valid measure of general intelligence and that its neural correlates could be better characterized by task fMRI than resting-state fMRI data.
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Mapeamento Encefálico , Encéfalo , Adulto Jovem , Humanos , Reprodutibilidade dos Testes , Vias Neurais , Encéfalo/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , CogniçãoRESUMO
OBJECTIVE: Impulsivity is influenced by genetic, neural, and environmental factors, but no study has examined how these factors work together to generate individual differences in impulsivity. The present study aimed to define the functional network that subserves impulsivity and test its relations with the gene-environment interactions found in the gene-environment-wide interaction study. METHOD: This study used a sample of healthy Chinese college students (N = 1,145) to identify gene-environment interactive effects on impulsivity, then defined the functional brain network related to impulsivity in an independent sample (N = 483), and explored the gene-brain associations using polygenic risk score. RESULTS: The present study found that 14 genes showed significant interactive effects with parental warmth (a protective environmental factor) and that six genes showed significant interactive effects with stressful life events (a risk environmental factor). The polygenic risk score for parental warmth was significantly correlated with functional connectivity especially the left middle frontal gyrus (MFG)-left inferior occipital and left MFG-left superior frontal gyrus functional connectivity, while the polygenic risk score for more stressful life events was significantly correlated with functional connectivity of left dorsal medial prefrontal cortex (DMPFC) to other regions. These associations were stronger in more adverse environments (i.e., low parental warmth or high stressful life events). CONCLUSIONS: This was the first gene-environment-wide interaction study of impulsivity. Future studies should replicate our results and explore the underlying mechanisms of these interactions. (PsycInfo Database Record (c) 2023 APA, all rights reserved).
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Interação Gene-Ambiente , Comportamento Impulsivo , Humanos , Encéfalo , Mapeamento Encefálico , Pais , Imageamento por Ressonância MagnéticaRESUMO
Enteric glial cells (EGCs) are the major component of the enteric nervous system and affect the pathophysiological process of intestinal motility dysfunction. MicroRNAs (miRNAs) play an important role in regulating gastrointestinal homeostasis. However, the mechanism of miRNA-mediated regulation of EGCs in intestinal dysmotility remains unclear. In this study, we investigated the effect of EGC apoptosis on intestinal dysmotility, and the effect of miR-26b-3p on EGC proliferation and apoptosis in vivo and in vitro. A loperamide hydrochloride (Lop)-induced constipated mouse model and an in vitro culture system of rat EGCs were established. The transcriptome was used to predict the differentially expressed gene miR-26b-3p and the target gene Frizzled 10 (FZD10), and their targeting binding relationship was verified by luciferase. EGCs were transfected with miR-26b-3p mimic or antagomir, and the FZD10 expression was down-regulated by siRNA. Immunofluorescence and flow cytometry were used to detect EGC apoptosis. MiR-26b-3p and FZD10 expressions were examined using quantitative real-time PCR (qRT-PCR). The CCK-8 assay was used to detect EGC proliferation. The protein levels were detected by Western blotting and enzyme-linked immunosorbent assay (ELISA). The results showed that miR-26b-3p was up-regulated in the Lop group, whereas FZD10 was down-regulated, and EGC apoptosis was increased in the colon of intestinal dysmotility mice. FZD10 down-regulation and miR-26b-3p mimic significantly increased glycogen synthase kinase-3ß phosphorylation (p-GSK3ß) levels, decreased ß-catenin expression, and promoted EGC apoptosis. MiR-26b-3p antagomir alleviated intestinal dysmotility, promoted EGC increased activity of EGCs, and reduced EGC apoptosis in vivo. In conclusion, this study indicated that miR-26b-3p promotes intestinal motility disorders by targeting FZD10 to block GSK3ß/ß-catenin signaling and induces apoptosis in EGCs. Our results provide a new research target for the treatment and intervention of intestinal dysmotility.
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MicroRNAs , beta Catenina , Animais , Camundongos , Ratos , Antagomirs , Apoptose , beta Catenina/metabolismo , Proliferação de Células , Glicogênio Sintase Quinase 3 beta/metabolismo , MicroRNAs/metabolismo , Neuroglia/metabolismo , Via de Sinalização Wnt/fisiologiaRESUMO
Solenopsis invicta is a main issue in southern China and is causing significant damage to the local ecological environment. The extensive use of insecticides has resulted in the development of tolerance in S. invicta. In our study, ten S. invicta colonies from Sichuan Province exhibited varying degrees of tolerance against flonicamid, with LC50 values from 0.49 mg/L to 8.54 mg/L. The sensitivity of S. invicta to flonicamid significantly increased after treatment with the P450 enzyme inhibitor piperonyl butoxide (PBO). Additionally, the activity of P450 in S. invicta was significantly enhanced after being treated with flonicamid. Flonicamid induced the expression levels of CYP4aa1, CYP9e2, CYP4C1, and CYP6A14. The expression levels of these P450 genes were significantly higher in the tolerant colonies compared to the sensitive colonies, and the relative copy numbers of CYP6A14 in the tolerant colonies were 2.01-2.15 fold. RNAi feeding treatment effectively inhibited the expression of P450 genes, thereby reducing the tolerance of S. invicta against flonicamid. In addition, the overexpression of CYP6A14 in D. melanogaster resulted in reduced sensitivity to flonicamid. Our investigations revealed hydrophobic interactions between flonicamid and seven amino acid residues of CYP6A14, along with the formation of a hydrogen bond between Glu306 and flonicamid. Our findings suggest that flonicamid can effectively control S. invicta and P450 plays a pivotal role in the tolerance of S. invicta against flonicamid. The overexpression of CYP6A14 also increased tolerance to flonicamid.
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Formigas , Inseticidas , Animais , Formigas Lava-Pés , Drosophila melanogaster , Inseticidas/toxicidadeRESUMO
AIM: To explore the correlation between diabetic retinopathy (DR) and Helicobacter pylori (Hp) infection, based on data from a physical examination population. METHODS: This cross-sectional retrospective analysis included data of 73 824 health examination participants from December 2018 to December 2019. Participants were divided into the diabetic group and non-diabetic group, non-diabetic retinopathy (NDR) group, non-proliferative diabetic retinopathy (NPDR) group, proliferative diabetic retinopathy (PDR) group, and Hp infection group. Gender, age, body mass index (BMI), systolic blood pressure (SBP), diastolic blood pressure (DBP), fasting plasma glucose (FPG), glycated hemoglobin A1c (HbA1c), triglycerides (TG), total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), and Hp data were recorded to compare the degree of DR lesions and Hp infection. Logistic regression analysis was used to evaluate the correlation between DR and Hp infection. RESULTS: There was a statistically significant difference between the diabetic and non-diabetic group (χ2=94.17, P<0.0001). Logistic regression analysis showed that male sex, age, BMI, SBP, TG, LDL-C, and Hp infection were independent risk factors for DR. There was no correlation between the degree of DR lesions and Hp infection (ρ=-0.00339, P=0.7753). Age [odds ratio (OR)=1.035, 95%CI: 1.024, 1.046, P<0.0001] and SBP (OR=1.009, 95%CI: 1.004, 1.015, P=0.0013) were independent risk factors for the degree of DR. CONCLUSION: There is a significant correlation between DR and Hp infection in the physical examination population. Hp infection is a risk factor for DR, and there is no significant difference between Hp infection and DR of different pathological degrees. Actively eradicating Hp may be of help to prevent DR.
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Individuals generally form their unique memories from shared experiences, yet the neural representational mechanisms underlying this subjectiveness of memory are poorly understood. The current study addressed this important question from the cross-subject neural representational perspective, leveraging a large functional magnetic resonance imaging dataset (n = 415) of a face-name associative memory task. We found that individuals' memory abilities were predicted by their synchronization to the group-averaged, canonical trial-by-trial activation level and, to a lesser degree, by their similarity to the group-averaged representational patterns during encoding. More importantly, the memory content shared between pairs of participants could be predicted by their shared local neural activation pattern, particularly in the angular gyrus and ventromedial prefrontal cortex, even after controlling for differences in memory abilities. These results uncover neural representational mechanisms for individualized memory and underscore the constructive nature of episodic memory.
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Memória Episódica , Humanos , Córtex Pré-Frontal/diagnóstico por imagem , Lobo ParietalRESUMO
A total of nine new phenolic amides (1-9), including four pairs of enantiomeric mixtures (3-5 and 8), along with ten known analogues (10-19) were identified from the fruits of Lycium barbarum using bioassay-guided chromatographic fractionation. Their structures were elucidated by comprehensive spectroscopic and spectrometric analyses, chiral HPLC analyses, and quantum NMR, and electronic circular dichroism calculations. Compounds 5-7 are the first example of feruloyl tyramine dimers fused through a cyclobutane ring. The activity results indicated that compounds 1, 11, and 13-17 exhibited remarkable inhibition against α-glucosidase with IC50 of 1.11-33.53 µM, 5-150 times stronger than acarbose (IC50 = 169.78 µM). Meanwhile, compounds 4a, 4b, 5a, 5b, 13, and 14 exerted moderate agonistic activities for peroxisome proliferator-activated receptor (PPAR-γ), with EC50 values of 10.09-44.26 µM. Especially,compound 14 also presented inhibitory activity on dipeptidyl peptidase-4 (DPPIV), with an IC50 value of 47.13 µM. Furthermore, the banding manner of compounds 14 and 17 with the active site of α-glucosidase, DPPIV, and PPAR-γ was explored by employing molecular docking analysis.
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Lycium , alfa-Glucosidases , alfa-Glucosidases/análise , Frutas/química , Lycium/química , Receptores Ativados por Proliferador de Peroxissomo , Agonistas PPAR-gama , Amidas , Simulação de Acoplamento Molecular , Fenóis/análise , Espectroscopia de Ressonância Magnética , Dipeptidil Peptidases e Tripeptidil Peptidases/análise , Estrutura Molecular , Inibidores de Glicosídeo Hidrolases/farmacologia , Inibidores de Glicosídeo Hidrolases/químicaRESUMO
The fall armyworm, Spodoptera frugiperda (Noctuidae: Lepidoptera), is a wide-reaching notorious insect pest of important cereal crops, which has developed resistance to multiple classes of insecticides. It invaded the Sichuan Province of China in 2019. In this study, we performed resistance monitoring of insecticides for 11 field-collected populations from Sichuan, and all the populations were susceptible to emamectin benzoate and chlorpyrifos. The variations in resistance level to indoxacarb (resistance ratio (RR), 9.23-45.53-fold), spinetoram (RR, 4.32-18.05-fold), and chlorantraniliprole (RR, 2.02-10.39-fold) were observed among these populations. To investigate the resistance mechanism of chlorantraniliprole, synergism tests were performed and showed that piperonyl butoxide had a slight synergistic effect on chlorantraniliprole for the QJ-20 population (1.43-fold) in moderate resistance (RR, 10.39-fold) compared with the treatment group without synergist. Furthermore, the expression scanning for resistance-related genes showed that five P450 genes (CYP6AE43, CYP321A8, CYP305A1, CYP49A1, and CYP306A1) and the ryanodine receptor gene (Ryr, chlorantraniliprole target) were overexpressed in the QJ-20 population. These results indicated that the fall armyworm in Sichuan has exhibited diverse susceptibilities to several classes of insecticides, and the overexpression of Ryr and several P450 genes may contribute to the development of resistance in S. frugiperda to chlorantraniliprole.
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Three new monomeric (1-3) and two newdimeric guaianolides (4 and 5), along with three known analogues (6-8) were isolated from the aerial part of Achillea alpina L. Compounds 1-3 were three novel 1,10-seco-guaianolides, while 4 and 5 were two novel 1,10-seco-guaianolides involved heterodimeric [4 + 2] adducts. The new structures were elucidated by analysis of spectroscopic data and quantum chemical calculations. All isolates were evaluated for their hypoglycemic activity with a glucose consumption model in palmitic acid (PA)-induced HepG2-insulin resistance (IR) cells, and compound 1 showed the most promising activity. A mechanistic study revealed that compound 1 appeared to mediate hypoglycemic activity via inhibition of the ROS/TXNIP/NLRP3/caspase-1 pathway.
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Achillea , Sesquiterpenos , Achillea/química , Estrutura Molecular , Hipoglicemiantes/farmacologia , Extratos Vegetais/química , Sesquiterpenos/farmacologia , Sesquiterpenos/químicaRESUMO
Risk genes and abnormal brain structural indices of psychiatric disorders have been extensively studied. However, whether genetic risk influences brain structure in the general population has been rarely studied. The current study enrolled 483 young Chinese adults, calculated their polygenic risk scores (PRS) for psychiatric disorders based on Psychiatric Genomics Consortium GWAS results, and examined the association between PRSs and brain volume. We found that PRSs were associated with the volume of many brain regions, with differences between PRS for different disorder, calculated at different threshold, and calculated using European or East Asian ancestry. Of them, the PRS for Major Depressive Disorder based on European ancestry was positively associated with right temporal gyrus; the PRS for schizophrenia based on East Asian ancestry was negatively associated with right precentral and postcentral gyrus; the PRS for schizophrenia based on European ancestry was positively associated with right superior temporal gyrus. All these brain regions are critical for corresponding disorders. However, no significant associations were found between PRS for Autism Spectrum Disorder / Bipolar Disorder and brain volume; and the association between PRS for Attention Deficit Hyperactivity Disorder at different thresholds and brain volume was inconsistent. These findings suggest distinct brain mechanisms underlying different psychiatric disorders.
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Transtorno do Deficit de Atenção com Hiperatividade , Transtorno do Espectro Autista , Transtorno Depressivo Maior , Adulto , Humanos , Transtorno Depressivo Maior/diagnóstico por imagem , Transtorno Depressivo Maior/genética , Encéfalo/diagnóstico por imagem , Fatores de Risco , Transtorno do Deficit de Atenção com Hiperatividade/genética , Estudo de Associação Genômica Ampla/métodos , Predisposição Genética para Doença/genéticaRESUMO
Six new flavonols, including four glucosylated flavonols (dysosmaflavonoid A-D), one phenylpropanoid-substituted flavonol (dysosmaflavonoid E), and one phenyl-substituted flavonol (dysosmaflavonoid F), together with five known analogues, were isolated from the roots and rhizomes of Dysosma versipellis. Their structures were elucidated by comprehensive analysis of their NMR, IR, UV, HRESIMS, and HPLC data. The antioxidant activities of all isolated compounds were examined by 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging assay. Compounds 2, 3, 5-8, and 12 exhibited significant DPPH scavenging capacity with IC50 values of 33.95, 39.02, 31.17, 32.79, 31.85, 30.48, and 23.75 µM, respectively, in comparison with Trolox (IC50, 15.80 µM). Compound 12 displayed more potent DPPH radical scavenging activity than prenylated and (or) glucosided derivatives (2-4, or 10). The preliminary structure-activity relationship showed that the catechol structure in flavonol is essential for DPPH radical scavenging effect.
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Berberidaceae , Flavonóis , Flavonóis/farmacologia , Flavonóis/química , Estrutura Molecular , Antioxidantes/farmacologia , Antioxidantes/química , Berberidaceae/química , Relação Estrutura-Atividade , Sequestradores de Radicais Livres/química , Compostos de Bifenilo , Picratos/químicaRESUMO
Cross-modal prediction serves a crucial adaptive role in the multisensory world, yet the neural mechanisms underlying this prediction are poorly understood. The present study addressed this important question by combining a novel audiovisual sequence memory task, functional magnetic resonance imaging (fMRI), and multivariate neural representational analyses. Our behavioral results revealed a reliable asymmetric cross-modal predictive effect, with a stronger prediction from visual to auditory (VA) modality than auditory to visual (AV) modality. Mirroring the behavioral pattern, we found the superior parietal lobe (SPL) showed higher pattern similarity for VA than AV pairs, and the strength of the predictive coding in the SPL was positively correlated with the behavioral predictive effect in the VA condition. Representational connectivity analyses further revealed that the SPL mediated the neural pathway from the visual to the auditory cortex in the VA condition but was not involved in the auditory to visual cortex pathway in the AV condition. Direct neural pathways within the unimodal regions were found for the visual-to-visual and auditory-to-auditory predictions. Together, these results provide novel insights into the neural mechanisms underlying cross-modal sequence prediction.
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Córtex Auditivo , Humanos , Vias Auditivas , Lobo Parietal , Imageamento por Ressonância Magnética/métodos , Percepção Auditiva , Percepção Visual , Estimulação Acústica , Estimulação LuminosaRESUMO
BACKGROUND: ADHD is associated with deficits in executive functions. Cognitive training is a promising nonpharmacological intervention for ADHD, however, there is insufficient evidence to guide the selection of training for individuals with ADHD. This pilot study aims to investigate the efficacy of executive function training targeting key executive dysfunctions in ADHD, compared with general executive function training which targets other executive functions. METHODS: A total of 127 subjects (6-12 years) diagnosed with ADHD were allocated to receive one of two different cognitive trainings. ADHD symptoms and cognitive functions were evaluated using parent-rated scales and CANTAB cognitive assessments. All participants were required to complete 48 training sessions within a two-month period. RESULTS: 94 out of 127 children completed the required training and assessments. Both ADHD executive function training group and general executive function training group showed significant improvement in ADHD symptoms on the ADHD Rating Scale and in executive function on the assessment of CANTAB. There was no significant difference in improvements between the two groups. Subgroup analysis suggested that children who had ADHD-RS total scores less than or equal to 28 at baseline showed greater improvement following ADHD executive function training. CONCLUSIONS: This study indicates that cognitive training can improve ADHD symptoms and executive function, with no difference in efficacy between targeted and generalized cognitive training. In addition, individuals with lower symptom severity may benefit more from training targeting key ADHD executive dysfunctions.
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Genetic studies on attention have mainly focused on children with attention-deficit/hyperactivity disorder (ADHD), so little systematic research has been conducted on genetic correlates of attention performance and their potential brain mechanisms among healthy individuals. The current study included a genome-wide association study (GWAS, N = 1145 healthy young adults) aimed to identify genes associated with sustained attention and an imaging genetics study (an independent sample of 483 healthy young adults) to examine any identified genes' influences on brain function. The GWAS found that TTLL11 showed genome-wide significant associations with sustained attention, with rs13298112 as the most significant SNP and the GG homozygotes showing more impulsive but also more focused responses than the A allele carriers. A retrospective examination of previously published ADHD GWAS results confirmed an un-reported, small but statistically significant effect of TTLL11 on ADHD. The imaging genetics study replicated this association and showed that the TTLL11 gene was associated with resting state activity and connectivity of the somatomoter network, and can be predicted by dorsal attention network connectivity. Specifically, the GG homozygotes showed lower brain activity, weaker brain network connectivity, and non-significant brain-attention association compared to the A allele carriers. Expression database showed that expression of this gene is enriched in the brain and that the G allele is associated with lower expression level than the A allele. These results suggest that TTLL11 may play a major role in healthy individuals' attention performance and may also contribute to the etiology of ADHD.
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Transtorno do Deficit de Atenção com Hiperatividade , Estudo de Associação Genômica Ampla , Peptídeo Sintases , Criança , Humanos , Adulto Jovem , Transtorno do Deficit de Atenção com Hiperatividade/genética , Encéfalo/diagnóstico por imagem , População do Leste Asiático , Imageamento por Ressonância Magnética/métodos , Vias Neurais , Estudos Retrospectivos , Peptídeo Sintases/genéticaRESUMO
OBJECTIVE: To explore the possible effects and mechanism of Zhizhu Decoction (ZZD) on the pathophysiology of slow transit constipation (STC). METHODS: A total of 54 C57BL/6 mice was randomly divided into the following 6 groups by a random number table, including control, STC model (model), positive control, and low-, medium- and high-doses ZZD treatment groups (5, 10, 20 g/kg, namely L, M-, and H-ZZD, respectively), 9 mice in each group. Following 2-week treatment, intestinal transport rate (ITR) and fecal water content were determined, and blood and colon tissue samples were collected. Hematoxylin-eosin and periodic acid-Schiff staining were performed to evaluate the morphology of colon tissues and calculate the number of goblet cells. To determine intestinal permeability, serum levels of lipopolysaccharide (LPS), low-density lipoprotein (LDL) and mannose were measured using enzyme-linked immunosorbent assay (ELISA). Western blot analysis was carried out to detect the expression levels of intestinal tight junction proteins zona-occludens-1 (ZO-1), claudin-1, occludin and recombinant mucin 2 (MUC2). The mRNA expression levels of inflammatory cytokines including tumor necrosis factor (TNF)-α, interleukin (IL)-1ß, IL-6, IL-4, IL-10 and IL-22 were determined using reverse transcription-quantitative reverse transcription reaction. Colon indexes of oxidative stress were measured by ELISA, and protein expression levels of colon silent information regulator 1/forkhead box O transcription factor 1 (SIRT1/FoxO1) antioxidant signaling pathway were detected by Western blot. RESULTS: Compared with the model group, ITR and fecal moisture were significantly enhanced in STC mice in the M-ZZD and H-ZZD groups (P<0.01). Additionally, ZZD treatment notably increased the thickness of mucosal and muscular tissue, elevated the number of goblet cells in the colon of STC mice, reduced the secretion levels of LPS, LDL and mannose, and upregulated ZO-1, claudin-1, occludin and MUC2 expressions in the colon in a dose-dependent manner, compared with the model group (P<0.05 or P<0.01). In addition, ZZD significantly attenuated intestinal inflammation and oxidative stress and activated the SIRT1/FoxO1 signaling pathway (P<0.05 or P<0.01). CONCLUSION: ZZD exhibited beneficial effects on the intestinal system of STC mice and alleviated intestinal inflammation and oxidative stress via activating SIRT1/FoxO1 antioxidant signaling pathway in the colon.
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Antioxidantes , Sirtuína 1 , Camundongos , Animais , Sirtuína 1/genética , Ocludina , Lipopolissacarídeos , Claudina-1 , Manose , Camundongos Endogâmicos C57BL , Constipação Intestinal/tratamento farmacológico , Inflamação , Transdução de SinaisRESUMO
Two new guaianolide-type sesquiterpenoids chrysanthemulides K and L (1 and 2), together with six known analogues (3-8), were isolated from an CH2Cl2 extract of the aerial parts of Chrysanthemum indicum. The structures of new compounds 1 and 2 were established by extensive spectroscopic analysis, including UV, IR, MS, NMR and computational electronic circular dichroism (ECD) methods. Inhibitory effects of all compounds on nitric oxide production were investigated in lipopolysaccharide (LPS)-induced RAW 264.7 cells. Results showed that compounds 1-8 displayed NO production inhibitory activity with IC50 values ranged from 3.5 to 34.3 µM.
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Chrysanthemum , Sesquiterpenos , Animais , Camundongos , Chrysanthemum/química , Células RAW 264.7 , Sesquiterpenos/química , Extratos Vegetais/farmacologia , Espectroscopia de Ressonância Magnética , Óxido Nítrico , Estrutura Molecular , Lipopolissacarídeos/farmacologiaRESUMO
One new 6a,11a-dehydropterocarpan derivative, 6-O-methyl-anhydrotuberosin (1), one new 6a-hydroxypterocarpan, (6aR,11aR,11bR)-hydroxytuberosone (7), and seven known compounds including two 6a,11a-dehydropterocarpans (2 and 4), two coumestans (3 and 5), one isoflavonoid (6) and two other phenolic compounds (8 and 9) were isolated from the roots of Pueraria lobata. The structures of the isolated compounds were elucidated with spectroscopic and spectrometric methods (1 D and 2DNMR, HRESIMS). Compounds 1, 2, 4-5 showed potent LSD1 inhibitory activities with IC50 values ranging from 1.73 to 4.99 µM. Furthermore, compound 2 showed potent cytotoxicity against gastric cancer cell lines MGC-803 and BGC-823, and lung cancer cell lines H1299 and H460.