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1.
J Exp Bot ; 2020 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-32182355

RESUMO

Polymethoxylated flavones (PMFs), which accumulate exclusively in fruit peel of citrus, play important physiological and pharmacological roles but the genetic basis for the methylation of flavonoids has not been fully elucidated in citrus. Here we characterize a caffeoyl-CoA O-methyltransferase-like enzyme, designated CrOMT1. The expression pattern of CrOMT1 was highly correlated with the concentration of the three major PMFs in two different citrus fruit tissues during fruit maturation. Exposure of fruit to UV-B radiation sharply increased the level of CrOMT1 transcripts and also led to the accumulation of three PMFs. The potential role of CrOMT1 was studied by testing the catalytic activity of recombinant CrOMT1 with numerous possible substrates in vitro. The enzyme could most efficiently methylate flavones with neighboring hydroxy moieties, with high catalytic efficiencies found with 6-OH- and 8-OH-containing compounds, preferences that correspond precisely with the essential methylation sites involved in the synthesis of the three naturally occurring PMFs in Citrus reticulata. This indicates that CrOMT1 is capable of in vitro methylation reactions required to synthesize PMFs in vivo. Furthermore, transient overexpression of CrOMT1 increased levels of the three major PMFs in fruit, indicating that CrOMT1 is likely to play an essential role in the biosynthesis of PMFs in citrus.

2.
Molecules ; 25(4)2020 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-32075249

RESUMO

O-methylation of flavonoids is an important modification reaction that occurs in plants. O-methylation contributes to the structural diversity of flavonoids, which have several biological and pharmacological functions. In this study, an O-methyltransferase gene (CrOMT2) was isolated from the fruit peel of Citrus reticulata, which encoding a multifunctional O-methyltransferase and could effectively catalyze the methylation of 3'-, 5'-, and 7-OH of flavonoids with vicinal hydroxyl substitutions. Substrate preference assays indicated that this recombinant enzyme favored polymethoxylated flavones (PMF)-type substrates in vitro, thereby providing biochemical evidence for the potential role of the enzyme in plants. Additionally, the cytotoxicity of the methylated products from the enzymatic catalytic reaction was evaluated in vitro using human gastric cell lines SGC-7901 and BGC-823. The results showed that the in vitro cytotoxicity of the flavonoids with the unsaturated C2-C3 bond was increased after being methylated at position 3'. These combined results provide biochemical insight regarding CrOMT2 in vitro and indicate the in vitro cytotoxicity of the products methylated by its catalytic reaction.

3.
Arch Virol ; 2020 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-32048042

RESUMO

Sapoviruses (SAVs), including several genogroups (GI to GV), are one of the causes of acute gastroenteritis (AGE). In this study, viral metagenomics revealed the presence of sapoviruses of different genogroups in stool from children with AGE. Eight different complete SAV genomes were determined, of which five belonged to GI and the other three belonged to GII, GIV and GV, respectively. Although they were highly similar to published sequences, the GIV and GV were the first complete genome sequences of these SAVs found in China. In a prevalence investigation, 19% of subjects with AGE were positive for SAVs, while none of the control group was positive.

4.
Neuroreport ; 31(4): 359-364, 2020 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-32058433

RESUMO

The categorical perception of lexical tones is important to understand tonal languages. Recent studies have provided electrophysiological evidence for the categorical perception of lexical tones at the cortical level; however, whether neural correlates exist at subcortical levels remain unknown. In this study, by using across-category and within-category lexical tone contrasts with the equivalent physical interval, we recorded deviance detection activities at both the brainstem (reflected by frequency following response) and cortical levels (reflected by mismatch negativity) simultaneously. We found that significantly enhanced intertrial phase-locking of frequency following response s was observed only during the across-category deviance detection, which indicates that phonological differences could be detected at the level of brainstem. In addition, the across-category deviants induced stronger mismatch negativity than within-category deviants. For the first time, our results demonstrate that neural correlates of categorical perception of lexical tones exist even in the brainstem, and suggests that both cortical and subcortical processes are involved in the coding and categorization of tonal information.

5.
J Sci Food Agric ; 100(3): 1124-1131, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31680259

RESUMO

BACKGROUND: Phthalates have been widely used as plasticizers in various industries and are widely focused on in the international community as a result of their reproductive toxicity. Exposure of Chinese residents to phthalates via edible vegetable oil occurs often. In the present study, gas chromatography-mass spectrometry was used to detect the two main phthalates bis(2-ethylhexyl) phthalate (DEHP) and dibutyl phthalate (DBP) in four major edible vegetable oil sources: an edible oil blend, soybean oil, peanut oil and rapeseed oil (a total of 1016 samples), as collected throughout China. Furthermore, cumulative risk assessment was used to estimate the reproductive health risk to Chinese residents caused by the phthalates that come from edible vegetable oils. RESULTS: Both phthalates were detected in four major edible vegetable oil sources. The phthalate with the highest detection rate was DBP (13.48%), followed by DEHP (7.78%). The results of the cumulative risk assessment showed that the hazard indices of these two phthalates in edible vegetable oils were less than 1, except in soybean oil. Nevertheless, the two phthalates had the lowest detection rates in soybean oil, which were 1.94% (DEHP) and 5.16% (DBP). In China, contamination levels of phthalates in the soils where oil crops are cultivated have a great influence on the phthalate concentrations in edible vegetable oils. CONCLUSION: It is recommended that Chinese residents who are consuming soybean oil choose well-known brands and regularly change their brand of consumption. The phthalates in edible vegetable oils pose a relatively small reproductive health risk to Chinese residents. © 2019 Society of Chemical Industry.


Assuntos
Contaminação de Alimentos/análise , Ácidos Ftálicos/análise , Óleos Vegetais/análise , Plastificantes/análise , China , Qualidade de Produtos para o Consumidor , Dibutilftalato/análise , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Medição de Risco
6.
Neuroreport ; 30(17): 1210-1214, 2019 12 10.
Artigo em Inglês | MEDLINE | ID: mdl-31599822

RESUMO

Musical training appears to enhance performance at both peripheral and central auditory sites. We compared behavioral and peripheral frequency tuning in normal-hearing musicians and nonmusicians, whose native language is Mandarin. The results indicate that, at higher probe frequencies, musical training sharpens behavioral tuning more saliently than peripheral tuning. The improved peripheral tuning for musician appears to result principally from efferent top-down control rather than local cochlear changes.

7.
Pharm Biol ; 57(1): 555-563, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31446815

RESUMO

Context: Lipopolysaccharide (LPS) is often used to induce immunoinflammatory reactions. TLR4/NFκB and NLRP3 signalling are major factors for inflammation. Dexamethasone (DXM) has an anti-immunoinflammatory effect. Objective: To investigate the inflammatory reaction in pathological changes of organs and the expression of inflammatory signalling during LPS infection. Materials and methods: ICR mice were divided into control group (n = 9), LPS group (n = 15) and LPS + DXM group (n = 14). LPS (10 mg/kg) was injected intravenously in LPS group and LPS + DXM group, normal saline was injected to the control group; DXM (0.5 mg/kg) was given by intragastric administration. 12 h after LPS, the blood was collected and the organs were isolated for biochemical analysis, protein expression, and morphological examination. Results: The results showed that BUN, Cre, ALT, AST in the LPS group increased distinctly by 81.42, 67.84, 40.53 and 36.05%, respectively, and CK, ALP, TP and ALB decreased by 71.37, 60.6, 12.57 and 19.73%, respectively, compared with the control group. In the morphologic observation, local necrosis in the liver, arterial vasodilation in the heart and kidney, alveolar secretions and pulmonary interstitial in the lungs, and mucosal shedding in the small and large intestines, the expression of TLR4-NFκB signalling were up-regulated distinctly whereas NLRP3 signalling was less broadly affected. DXM can decrease BUN and Cre, downregulate the expression of TLR4-NFκB signalling, but has no effect on the organ damage based on morphology. Conclusion: Acute injuries induced by LPS are extensive. The inflammatory damage in small and large intestines, liver and kidney was more severe than other organs. TLR4-NFκB signalling was the major response to LPS stress.


Assuntos
Intestinos/efeitos dos fármacos , Rim/efeitos dos fármacos , Lipopolissacarídeos/farmacologia , Fígado/efeitos dos fármacos , NF-kappa B/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Receptor 4 Toll-Like/metabolismo , Animais , Biomarcadores/sangue , Inflamação , Injeções Intravenosas , Intestinos/imunologia , Rim/imunologia , Rim/metabolismo , Lipopolissacarídeos/administração & dosagem , Fígado/imunologia , Fígado/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos ICR , Transdução de Sinais
8.
Artigo em Inglês | MEDLINE | ID: mdl-31275420

RESUMO

Anemoside B4 (B4) isolated from Radix Pulsatilla has anti-inflammatory activities in the colon and antitumor effects. However, its role in the prevention and treatment of kidney injury has not been reported. Here, we reported the effects of B4 on chronic kidney injury (CKI) and studied its related mechanism based on an adenine-induced kidney injury model in rats. The results showed that serum BUN (blood urea nitrogen), Crea (creatinine), and urinary proteins increased significantly after oral administration of adenine. Meanwhile, the adenine contents in both renal tissue and urine increased markedly compared with those of normal rats. Moreover, IL-1ß, IL-6, TNFα, and NFκB expression was upregulated in the kidney. Simultaneously, the expression of NLRP3 (the nucleotide-binding and oligomerization domain-like receptor, leucine-rich repeat and pyrin domain-containing 3) in the inflammasome, which consists of Caspase 1, ASC (apoptosis-associated speck-like protein containing a caspase recruitment domain), and IL-18, was significantly upregulated. B4 could significantly decrease BUN and Crea; reduce urinary proteins in rats; suppress the expression of IL-6, IL-1ß, NFκB, NLRP3, Caspase 1, ASC, and IL-18; and increase urinary adenine contents and promote its excretion. In addition, B4 also upregulated the expression of podocin and nephrin, two major podocyte proteins, and reduced the fiber collagen in the renal interstitial, suggesting that B4 could protect the glomerular matrix from adenine injury in addition to its anti-inflammatory effects. The results of this study show new perspective of B4 as a potential drug against adenine-induced renal injury.

9.
Zhongguo Zhong Yao Za Zhi ; 44(5): 996-1003, 2019 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-30989861

RESUMO

In this study,in-depth systematic evaluation of rat of acute kidney injury(AKI) caused by renal arteriovenous ligation was conducted to better master and apply this model for drug research. Male SD rats of 2-3 months old were employed in this study.The left kidney was removed,and the right kidney received ligation for 40 min and reperfusion for 24 h. Serum creatinine(Crea),urea nitrogen(BUN) and the renal tissue sections were assayed as the basic indicators to evaluate their renal function. The mRNA expression of inflammatory necrosis factors and apoptotic factors was used to evaluate the mechanism of molecular pathophysiological changes. The results showed that the serum Crea and BUN caused by ligation of both renal arteries and veins were significantly higher than those of rats with renal artery ligation. After renal arteriovenous ligation for 40 min and reperfusion for 24 h in rats,the serum Crea of the rats varied from less than 100 µmol·L-1 to more than 430 µmol·L-1. Among them,5 rats showed less than 100 µmol·L-1 serum Crea,20 rats with 100-200 µmol·L-1 serum Crea and 12 rats with more than 430 µmol·L-1. Rats with serum Crea between 300-430 µmol·L-1 accounted for 66.3%(122/184) of the total number of the experiment rats. After 72 h reperfusion,serum Crea in the group of Crea 370-430 µmol·L-1 continued to increase,while the serum Crea in the group of Crea 200-300 µmol·L-1 and the group of Crea 300-370 µmol·L-1 recovered quickly. No matter serum Crea was elevated or decreased,the renal tubules showed pathological changes such as vacuolar degeneration or even necrosis. The mRNA expression levels of Toll-like receptor(TLR4),tumor necrosis factor(TNF-α) and interleukin(IL-6) in renal tissueswere significantly up-regulated,and the effect was most obvious in the group of serum Crea 370-430 µmol·L-1. The study indicated that the model for AKI caused by renal arteriovenous ligation and reperfusion is easy to operate,and the serum Crea and BUN have the characteristics of continuous increase,beneficial to the observation of drug effects. This acute kidney injury is mainly related to the pathophysiological response of inflammatory necrosis.


Assuntos
Lesão Renal Aguda/patologia , Traumatismo por Reperfusão , Animais , Nitrogênio da Ureia Sanguínea , Creatinina/sangue , Modelos Animais de Doenças , Rim/patologia , Túbulos Renais/patologia , Ligadura , Masculino , Ratos , Ratos Sprague-Dawley , Artéria Renal
10.
Front Neurosci ; 13: 130, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30872990

RESUMO

The neural generators of the frequency-following response (FFR), a neural response widely used to study the human auditory system, remain unclear. There is evidence that the balance between cortical and subcortical contributions to the FFR varies with stimulus frequency. In this study, we tried to clarify whether this variation extended to subcortical nuclei at higher stimulus frequencies where cortical sources were inactive. We evoked FFRs, in 17 human listeners with normal hearing (9 female), with three complex tones with missing-fundamentals corresponding to musical tones C4 (262 Hz), E4 (330 Hz), and G4 (393 Hz) presented to left, right, or both ears. Source imaging results confirmed the dominance of subcortical activity underlying both fundamental frequency (F0) and second harmonic (H2) components of the FFR. Importantly, several FFR features (spatial complexity, scalp distributions of spectral strength and inter-trial phase coherence, and functional connectivity patterns) varied systematically with stimulus F0, suggesting an unfixed source configuration. We speculated that the variation of FFR source configuration with stimulus frequency resulted from changing relative contributions of subcortical nuclei. Supportively, topographic comparison between the FFR and the auditory brainstem response (ABR) evoked by clicks revealed that the topography of the F0 component resembled that of the click-ABR at an earlier latency when stimulus F0 was higher and that the topography of the H2 component resembled that of the click-ABR at a nearly fixed latency regardless of stimulus F0, particularly for binaurally evoked FFRs. Possible generation sites of the FFR and implications for future studies were discussed.

11.
Ying Yong Sheng Tai Xue Bao ; 30(3): 941-950, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30912387

RESUMO

The accumulation of heavy metals in soil has serious influence on plant growth and ecosystem balance. It is of great importance to explore the mechanism of plant tolerance to heavy me-tals. Although spinach is supposed to have strong Cu tolerance, the effects of Cu on mineral element absorption and cell ultrastructure are still unclear. In this study, the growth of spinach seedlings, the absorption of mineral elements and the ultrastructure of leaf cells were examined in a pot experiment. The results showed that Cu2+ accumulation in the root of spinach seedling was less than that in the shoot when CuSO4 concentration was 100 mg·L-1, with root growth being increased and shoot growth being slightly decreased. When copper concentration continued to increase, the growth parameters continuously declined. When the CuSO4 concentrations were less than 400 mg·L-1, the foliar N, K, Ca, Mg and Fe concentrations of spinach seedling increased, and that of P decreased. The concentrations of N, P and K in roots went down and that of Ca, Mg and Fe went up. All organelles in leaf cells were clearly visible. The basal granule layer was arranged orderly, and the inner and outer membranes of chloroplasts were intact. When the CuSO4 concentrations exceeded 600 mg·L-1, foliar N concentration increased while that of P, K, Ca, Mg and Fe decreased. The concentrations of N, P, K, Ca, Mg and Fe in roots declined. The cell ultrastructure of spinach seedlings substantially changed with the increases of CuSO4 treated concentrations. The chloroplast in leaf cells became rounder, the chloroplast membrane became thinner, the stroma and basal granule layer became less, and the layer accumulation height decreased. The nucleus was broken up and small black spots were found in vacuoles and cell walls, which might be attributed to the enhancement of intracellular swelling pressure caused by high accumulation of Cu2+. In conclusion, low concentration of CuSO4 had little negative effect on the life activities of spinach seedlings, and the high concentrations of CuSO4 did not terminate their growth, indicating that spinach seedlings had strong copper resistance.


Assuntos
Plântula , Spinacia oleracea , Cobre , Minerais , Nutrientes , Raízes de Plantas
12.
Mol Med Rep ; 19(4): 2537-2550, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30720084

RESUMO

Earthworms are useful indicator organisms of soil health and Eisenia fetida have been extensively used as test organisms in ecotoxicological studies. In order to gain insight into the gene expression profiles associated with physiological functions of earthworms, a full­length enriched cDNA library of the Eisenia fetida genome was successfully constructed using Switching Mechanism at 5'End of RNA Template technology. Construction of a cDNA library and analysis of Expressed Sequence Tags (ESTs) are efficient approaches for collecting genomic information and identifying genes important for a given biological process. Furthermore, analysis of the expression abundance of ESTs was performed with the aim of providing genetic and transcriptomic information on the development and regenerative process of earthworms. Phrep and Crossmatch were used to process EST data and a total of 1,140 high­quality EST sequences were determined by sequencing random cDNA clones from the library. Clustering analysis of sequences revealed a total of 593 unique sequences including 225 contiguous and 368 singleton sequences. Basic Local Alignment Search Tool analysis against the Kyoto Encyclopedia of Genes and Genomes database resulted in 593 significant hits (P­value <1x10­8), of which 168 were annotated through Gene Ontology analysis. The STRING database was used to determine relationships among the 168 ESTs, identifying associated genes involved in protein­protein interactions and gene expression regulation. Based on nucleic acid and protein sequence homology, the mutual relationships between 287 genes could be obtained, which identified a portion of the ESTs as known genes. The present study reports on the construction of a high­quality cDNA library representative of adult earthworms, on a preliminary analysis of ESTs and on a putative functional analysis of ESTs. The present study is expected to enhance our understanding of the molecular basis underlying the biological development of earthworms.


Assuntos
Etiquetas de Sequências Expressas , Biblioteca Gênica , Oligoquetos/genética , Análise de Sequência de DNA , Animais , Biologia Computacional/métodos , Ontologia Genética , Anotação de Sequência Molecular
13.
Ecotoxicol Environ Saf ; 171: 771-780, 2019 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-30660970

RESUMO

Examination of plants with strong Cu tolerance and an understanding of their Cu-tolerance mechanisms are of considerable significance for the remediation of Cu-contaminated soil. Although spinach may be a plant with strong Cu tolerance, the threshold of Cu tolerance in this plant and its physiological response mechanisms to Cu are still unclear. In this study, we examined that the effects of different Cu concentrations on the growth parameters, antioxidant enzyme activities, and photosynthesis of spinach seedlings. The results showed that when treated with a low Cu concentration (100 mg L-1 CuSO4), the biomass of spinach seedlings increased, whereas the MDA content, the activities of antioxidant enzymes, Pn, gs and Tr were not significantly different from those in the control (P > 0.05), and Y(II), qP reached their maximum values, indicating that a low Cu concentration (100 mg L-1 CuSO4) had minimal negative effects on the life activities of spinach seedlings. In contrast, when treated with high Cu concentrations (800-1000 mg L-1 CuSO4), the total biomass of spinach seedlings was markedly decreased, the MDA contents increased, antioxidant enzyme activities initially increased and then decreased to varying degrees, the contents of chlorophyll, Pn, Tr, Fv/Fm, qP, NPQ, and Y(II) were all decreased. However the growth of spinach did not terminate, implying that the lethal threshold concentration of Cu for spinach is greater than 1000 mg L-1 CuSO4 used in this study. In summary, spinach exhibits a high tolerance to Cu and can be considered as an alternative plant for the remediation of Cu-contaminated soils.


Assuntos
Cobre/toxicidade , Poluentes do Solo/toxicidade , Spinacia oleracea/efeitos dos fármacos , Clorofila/metabolismo , Fotossíntese/efeitos dos fármacos , Plântula/efeitos dos fármacos , Plântula/fisiologia , Spinacia oleracea/fisiologia , Superóxido Dismutase/metabolismo
14.
Mol Brain ; 12(1): 118, 2019 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-31888678

RESUMO

Chronic corticosterone (CORT) stress is an anxiety and depression inducing factor that involves the dysfunction of glucocorticoid receptor (GR), brain-derived neurotrophic factor (BDNF), and neuronal plasticity. However, the regulation of proteomic profiles in neurons suffering CORT stress is remaining elusive. Thus, the proteomic profiles of mouse neuronal C17.2 stem cells were comprehensively investigated by TMT (tandem mass tag)-labeling quantitative proteomics. The quantitative proteomics conjugated gene ontology analysis revealed the inhibitory effect of CORT on the expression of mitochondrial oxidative phosphorylation-related proteins, which can be antagonized by berberine (BBR) treatment. In addition, animal studies showed that changes in mitochondria by CORT can affect neuropsychiatric activities and disturb the physiological functions of neurons via disordering mitochondrial oxidative phosphorylation. Thus, the mitochondrial energy metabolism can be considered as one of the major mechanism underlying CORT-mediated depression. Since CORT is important for depression after traumatic stress disorder, our study will shed light on the prevention and treatment of depression as well as posttraumatic stress disorder (PTSD).

15.
Nat Commun ; 9(1): 4993, 2018 11 26.
Artigo em Inglês | MEDLINE | ID: mdl-30478312

RESUMO

Signals arising from bacterial infections are detected by pathogen recognition receptors (PRRs) and are transduced by specialized adapter proteins in mammalian cells. The Receptor-interacting-serine/threonine-protein kinase 2 (RIPK2 or RIP2) is such an adapter protein that is critical for signal propagation of the Nucleotide-binding-oligomerization-domain-containing proteins 1/2 (NOD1 and NOD2). Dysregulation of this signaling pathway leads to defects in bacterial detection and in some cases autoimmune diseases. Here, we show that the Caspase-activation-and-recruitment-domain (CARD) of RIP2 (RIP2-CARD) forms oligomeric structures upon stimulation by either NOD1-CARD or NOD2-2CARD. We reconstitute this complex, termed the RIPosome in vitro and solve the cryo-EM filament structure of the active RIP2-CARD complex at 4.1 Å resolution. The structure suggests potential mechanisms by which CARD domains from NOD1 and NOD2 initiate the oligomerization process of RIP2-CARD. Together with structure guided mutagenesis experiments at the CARD-CARD interfaces, we demonstrate molecular mechanisms how RIP2 is activated and self-propagating such signal.


Assuntos
Proteína Serina-Treonina Quinase 2 de Interação com Receptor/química , Proteína Serina-Treonina Quinase 2 de Interação com Receptor/metabolismo , Transdução de Sinais , Sequência de Aminoácidos , Proteínas Adaptadoras de Sinalização CARD/química , Proteínas Adaptadoras de Sinalização CARD/metabolismo , Microscopia Crioeletrônica , Células HEK293 , Humanos , Modelos Moleculares , Ligação Proteica , Domínios Proteicos , Multimerização Proteica , Proteína Serina-Treonina Quinase 2 de Interação com Receptor/ultraestrutura , Proteínas Recombinantes/metabolismo , Relação Estrutura-Atividade
16.
J Pain Res ; 11: 763-769, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29695928

RESUMO

Background: Previous studies suggested that single-nucleotide polymorphisms in dopamine receptor D2 (DRD2) are the susceptibility loci for migraine. This study was aimed at evaluating the contribution of DRD2 rs1800497 and its expression to migraine risk in Han Chinese subjects. Methods: In total, 250 patients with migraine and 250 age- and sex-matched control subjects were included in this study. TaqMan allelic discrimination assay was used for DRD2 rs1800497 genotyping. Plasma DRD2 concentration was determined using enzyme-linked immunosorbent assay. Results: Significant associations were observed for the rs1800497 genotype (c2=6.37, p=0.041) and allele (c2=4.69, p=0.03; odds ratio [OR]=1.33, 95% CI=1.03-1.72, power=58%) frequencies between the migraine and control groups. Sex analysis indicated a positive association for rs1800497 between female patients with migraine and control individuals (genotype: c2=7.84, p=0.019; allele: c2=6.60, p=0.010; OR=1.61, 95% CI=1.12-2.30, power=73.4%). Furthermore, a significant association was observed only in female patients with migraine without aura (MO) (genotype: c2=6.88, p=0.032; allele: c2=5.65, p=0.017; OR=1.59, 95% CI=1.08-2.36, power=65.1%). The mean plasma DRD2 levels in the control group (mean±SD: 24.20±2.78) were significantly lower than those in the migraine with aura (MA) (30.86±3.69, p<0.0001) and MO groups (31.88±4.99, p<0.0001). Additionally, there was a sex-based difference in DRD2 expression in the MA (male vs female: 29.46±3.59 vs 32.27±3.27, p<0.01) and MO groups (male vs female: 29.18±3.50 vs 34.58±4.84, p<0.0001). Moreover, plasma DRD2 levels in patients were significantly different among the three genotypes (CC vs CT vs TT: 24.76±3.76 vs 30.93±3.85 vs 37.06±3.95, p<0.0001). Similar results were observed both in the MA (CC vs CT vs TT: 25.09±3.84 vs 28.57±2.84 vs 33.37±1.58, p<0.0001) and MO groups (CC vs CT vs TT: 24.65±3.79 vs 31.65±3.86 vs 38.29±3.74, p<0.0001). Conclusion: Our case-control study suggested that the DRD2 polymorphism rs1800497 was significantly associated with the risk of migraine in Han Chinese females. Additionally, the plasma DRD2 level was high in patients with migraine. Females with migraine had considerably higher DRD2 levels than males with migraine. DRD2 expression may be regulated by DRD2 rs1800497 genotype in patients with migraine.

17.
Neuroscience ; 373: 60-71, 2018 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-29337239

RESUMO

Since sound perception takes place against a background with a certain amount of noise, both speech and non-speech processing involve extraction of target signals and suppression of background noise. Previous works on early processing of speech phonemes largely neglected how background noise is encoded and suppressed. This study aimed to fill in this gap. We adopted an oddball paradigm where speech (vowels) or non-speech stimuli (complex tones) were presented with or without a background of amplitude-modulated noise and analyzed cortical responses related to foreground stimulus processing, including mismatch negativity (MMN), N2b, and P300, as well as neural representations of the background noise, that is, auditory steady-state response (ASSR). We found that speech deviants elicited later and weaker MMN, later N2b, and later P300 than non-speech ones, but N2b and P300 had similar strength, suggesting more complex processing of certain acoustic features in speech. Only for vowels, background noise enhanced N2b strength relative to silence, suggesting an attention-related speech-specific process to improve perception of foreground targets. In addition, noise suppression in speech contexts, quantified by ASSR amplitude reduction after stimulus onset, was lateralized towards the left hemisphere. The left-lateralized suppression following N2b was associated with the N2b enhancement in noise for speech, indicating that foreground processing may interact with background suppression, particularly during speech processing. Together, our findings indicate that the differences between perception of speech and non-speech sounds involve not only the processing of target information in the foreground but also the suppression of irrelevant aspects in the background.


Assuntos
Percepção Auditiva/fisiologia , Encéfalo/fisiologia , Fonética , Eletroencefalografia , Potenciais Evocados , Feminino , Humanos , Masculino , Testes Neuropsicológicos , Reconhecimento Fisiológico de Modelo/fisiologia , Adulto Jovem
18.
Artif Cells Nanomed Biotechnol ; 46(sup1): 372-379, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29327607

RESUMO

BACKGROUND: Neurotoxicity induced by the local anaesthetics has aroused concern. A previous study has shown that an overload of intracellular calcium was involved in the neurotoxic effect. Cav3.1 is one of the low-voltage-activated (LVA) calcium channels which play a key point to regulate the intracellular calcium ion level. This study aimed to investigate the changes of the Cav3.1 expression in the SH-SY5Y cells treated with lidocaine hydrochloride. METHODS: The SH-SY5Y cells were treated with different concentrations of lidocaine hydrochloride(1 mM, 5 mM and 10 mM, namely L1 group, L5 group and L10 group) and different exposure times (1 h,12 h and 24 h), respectively. Cell viability, Cav3.1 protein and mRNA expression were detected. RESULTS: The results showed that cell viability decreased and Cav3.1 mRNA and protein expression increased with the concentration (from 1 mM to 10 mM) of the lidocaine hydrochloride and exposure time (from 1 h to 24 h) to the SH-SY5Y cell line increased. CONCLUSION: Those data showed that lidocaine hydrochloride induced SH-SY5Y cell toxicity and up-regulated Cav3.1mRNA and protein expression.


Assuntos
Anestésicos Locais/farmacologia , Canais de Cálcio Tipo T/genética , Canais de Cálcio Tipo T/metabolismo , Lidocaína/farmacologia , Regulação para Cima/efeitos dos fármacos , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Humanos , RNA Mensageiro/genética , RNA Mensageiro/metabolismo
19.
Acta Psychol (Amst) ; 180: 79-87, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28918225

RESUMO

The aim of the current study is to provide new insights into the relationship between executive functions and intelligence measures in considering the item-position effect observed in intelligence items. Raven's Advanced Progressive Matrices (APM) and Horn's LPS reasoning test were used to assess fluid intelligence which served as criterion in investigating the relationship between intelligence and executive functions. A battery of six experimental tasks measured the updating, shifting, and inhibition processes of executive functions. Data were collected from 205 university students. Fluid intelligence showed substantial correlations with the updating and inhibition processes and no correlation with the shifting process without considering the item-position effect. Next, the fixed-link model was applied to APM and LPS data separately to decompose them into an ability component and an item-position component. The results of relating the components to executive functions showed that the updating and shifting processes mainly contributed to the item-position component whereas the inhibition process was mainly associated with the ability component of each fluid intelligence test. These findings suggest that improvements in the efficiency of updating and shifting processes are likely to occur during the course of completing intelligence measures and inhibition is important for intelligence in general.


Assuntos
Função Executiva/fisiologia , Inteligência/fisiologia , Memória de Curto Prazo/fisiologia , Resolução de Problemas/fisiologia , Adolescente , Adulto , Feminino , Humanos , Testes de Inteligência , Masculino , Testes Neuropsicológicos , Adulto Jovem
20.
PLoS One ; 12(5): e0178385, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28562624

RESUMO

A promising approach for brain-computer interfaces (BCIs) employs the steady-state visual evoked potential (SSVEP) for extracting control information. Main advantages of these SSVEP BCIs are a simple and low-cost setup, little effort to adjust the system parameters to the user and comparatively high information transfer rates (ITR). However, traditional frequency-coded SSVEP BCIs require the user to gaze directly at the selected flicker stimulus, which is liable to cause fatigue or even photic epileptic seizures. The spatially coded SSVEP BCI we present in this article addresses this issue. It uses a single flicker stimulus that appears always in the extrafoveal field of view, yet it allows the user to control four control channels. We demonstrate the embedding of this novel SSVEP stimulation paradigm in the user interface of an online BCI for navigating a 2-dimensional computer game. Offline analysis of the training data reveals an average classification accuracy of 96.9±1.64%, corresponding to an information transfer rate of 30.1±1.8 bits/min. In online mode, the average classification accuracy reached 87.9±11.4%, which resulted in an ITR of 23.8±6.75 bits/min. We did not observe a strong relation between a subject's offline and online performance. Analysis of the online performance over time shows that users can reliably control the new BCI paradigm with stable performance over at least 30 minutes of continuous operation.


Assuntos
Interfaces Cérebro-Computador , Navegação Espacial , Adulto , Feminino , Fusão Flicker , Humanos , Masculino , Jogos de Vídeo , Adulto Jovem
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