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1.
Biol Trace Elem Res ; 200(1): 308-317, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33634365

RESUMO

Aluminum exposure can mediate either acute toxicity or chronic toxicity. Aluminum exerts toxic effects on the cardiovascular system, but there are few studies on its related mechanisms. In this study, we investigated the molecular mechanism of aluminum-induced oxidative damage and apoptosis in rat cardiomyocytes. Thirty-two male Wistar rats were randomly divided into four groups, including the control group (GC), low-dose group of aluminum exposure (GL), medium-dose group (GM), and high-dose group (GH), with eight rats in each group. The GL, GM, and GH groups were given 5, 10, and 20 mg/(kg·d) of AlCl3 solution by intraperitoneal injection, and the GC group received intraperitoneal injection of the same volume of normal saline (2 ml/rat/day), 5 times a week for 28 days. At the end of the experiment, the levels of aluminum, malondialdehyde (MDA), plasma lactate dehydrogenase (LDH), creatine kinase (CK), creatine kinase isoenzyme (CKMB), and alpha-hydroxybutyrate dehydrogenase (HBDH) were measured. The pathological changes of myocardium were observed by H&E staining. The apoptosis of cardiomyocytes was detected by TUNEL staining, and the expression of apoptosis-related proteins was determined by western blot. The results showed that the levels of CKMB and HBDH in the GM and GH groups were significantly higher than those in the GC group (P < 0.05). The content of aluminum in the myocardium and serum of the aluminum exposure groups was significantly higher than that of the GC group (P < 0.05). The level of MDA in the GM and GH groups was significantly higher than that in the GC group (P < 0.05). The pathological results showed that vacuolated and hypertrophied cardiomyocytes were found in aluminum exposure groups, especially in the GM and GH groups. The TUNEL staining showed that the apoptosis rate of the aluminum exposure groups was considerably higher than that of the GC group (P < 0.05). Western blot showed that the expression of Bcl-2, an anti-apoptotic protein, in cardiomyocytes of aluminum exposure groups was lower than that of the GC group (P < 0.05), while the levels of Bax and caspase-3 in the cardiomyocytes of the GM and GH groups were higher than those of the GC group (P < 0.05). The experimental results showed that aluminum could accumulate in myocardial tissues and cause damage to cardiomyocytes. It could induce oxidative stress damage by increasing the content of MDA in cardiomyocytes and trigger cardiomyocyte apoptosis by activating the pro-apoptotic proteins caspase-3 and Bax and reducing the anti-apoptotic protein Bcl-2.


Assuntos
Alumínio , Miócitos Cardíacos , Alumínio/metabolismo , Alumínio/toxicidade , Animais , Apoptose , Masculino , Miócitos Cardíacos/metabolismo , Estresse Oxidativo , Ratos , Ratos Wistar
2.
J Exp Psychol Hum Percept Perform ; 47(6): 784-794, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33983788

RESUMO

The advantages of face processing over processing items in other object categories have been found in conditions both with and without visual awareness. This study examined the possible mechanisms underlying the advantages of processing visible and invisible faces. Specifically, contributions from face-like configurations and face-specific local attributes were evaluated by comparing perceptual processes of three image types: genuine faces, face-like objects, and non-face-like objects. Illusory face perception induced from face-like objects largely depended on information from a global configuration level, with a high tolerance for variations in local features. Comparable processing advantages for real faces and face-like objects were observed in invisible conditions using interocular rivalry and crowding paradigms. However, the visible face advantage seemed to be exclusive to genuine faces. These results suggest that the face processing privilege is twofold: It is strongly triggered by global configuration without visual awareness, but with awareness, it relies on facial local attributes. (PsycInfo Database Record (c) 2021 APA, all rights reserved).


Assuntos
Reconhecimento Facial , Ilusões , Conscientização , Humanos , Percepção Visual
3.
Biomed Res Int ; 2021: 6653802, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33860048

RESUMO

Objective: Multiple genes have been identified to cause dilated cardiomyopathy (DCM). Nevertheless, there is still a lack of comprehensive elucidation of the molecular characteristics for DCM. Herein, we aimed to uncover putative molecular features for DCM by multiomics analysis. Methods: Differentially expressed genes (DEGs) were obtained from different RNA sequencing (RNA-seq) datasets of left ventricle samples from healthy donors and DCM patients. Furthermore, protein-protein interaction (PPI) analysis was then presented. Differentially methylated genes (DMGs) were identified between DCM and control samples. Following integration of DEGs and DMGs, differentially expressed and methylated genes were acquired and their biological functions were analyzed by the clusterProfiler package. Whole exome sequencing of blood samples from 69 DCM patients was constructed in our cohort, which was analyzed the maftools package. The expression of key mutated genes was verified by three independent datasets. Results: 1407 common DEGs were identified for DCM after integration of the two RNA-seq datasets. A PPI network was constructed, composed of 171 up- and 136 downregulated genes. Four hub genes were identified for DCM, including C3 (degree = 24), GNB3 (degree = 23), QSOX1 (degree = 21), and APOB (degree = 17). Moreover, 285 hyper- and 321 hypomethylated genes were screened for DCM. After integration, 20 differentially expressed and methylated genes were identified, which were associated with cell differentiation and protein digestion and absorption. Among single-nucleotide variant (SNV), C>T was the most frequent mutation classification for DCM. MUC4 was the most frequent mutation gene which occupied 71% across 69 samples, followed by PHLDA1, AHNAK2, and MAML3. These mutated genes were confirmed to be differentially expressed between DCM and control samples. Conclusion: Our findings comprehensively analyzed molecular characteristics from the transcriptome, epigenome, and genome perspectives for DCM, which could provide practical implications for DCM.


Assuntos
Cardiomiopatia Dilatada/genética , Epigenoma , Genoma Humano , Genômica , Transcriptoma/genética , Cardiomiopatia Dilatada/sangue , Metilação de DNA/genética , Feminino , Perfilação da Expressão Gênica , Ontologia Genética , Ventrículos do Coração/metabolismo , Ventrículos do Coração/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Anotação de Sequência Molecular , Mutação/genética , Polimorfismo de Nucleotídeo Único/genética , Mapas de Interação de Proteínas/genética , Reprodutibilidade dos Testes , Sequenciamento Completo do Exoma
4.
J Exp Psychol Hum Percept Perform ; 44(5): 806-817, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29154626

RESUMO

Does attention alter appearance? Recent studies have shown that an exogenous cue tends to increase the perceived contrast of a low-contrast stimulus. In the present study we systematically studied the attentional effect over a wide range of contrast levels (15% to 60%). Besides replicating the enhancement at lower contrast levels with higher comparative tasks (Experiment 1), the data revealed a cue-induced attenuation in apparent contrast at higher contrast levels with lower comparative tasks (Experiment 2) and same/different judgment task (Experiment 3). This attenuation effect was robust at the individual level, and it was not due to response bias or sensory interactions (Experiments 3 and 4). These results suggest that attention modulates contrast appearance and this effect depends on both the contrast level and the type of judgment task used. We propose that our findings can be understood through contrast gain mechanism on supersatuating neurons, whose response increases first as the stimulus intensity increases, but decrease the responses after the peak. This surprising phenomenon offers insights for the underlying neural mechanisms of visual processing. (PsycINFO Database Record


Assuntos
Atenção/fisiologia , Sensibilidades de Contraste/fisiologia , Sinais (Psicologia) , Desempenho Psicomotor/fisiologia , Adolescente , Adulto , Feminino , Humanos , Masculino , Adulto Jovem
5.
J Environ Radioact ; 165: 159-167, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27723528

RESUMO

A series of laboratory-scale combustion tests were conducted under well-controlled conditions to measure the release of 90Sr and 137Cs nuclides to the atmosphere (air) from combustion of vegetation and organic soil samples contaminated with radioactivity. These vegetation and soil samples were collected from a controlled contaminated forest area within the Canadian Nuclear Laboratories - Chalk River site. The combustion products including ash and smoke particulates, along with gaseous emissions, were collected and then analyzed for 137Cs and 90Sr concentrations by radiometric techniques. The experimental results reveal that the releases of 90Sr to the atmosphere (air) from combustion of vegetation are very low with most of the 90Sr activity remaining in ash residues, even at a temperature of 800 °C. The detailed combustion experiments with surface litter and twigs, alder twigs, alder leaves, and organic soil indicate that 0.5 ± 0.1%, 0.3 ± 0.1%, 0.9 ± 0.1%, and 0.3 ± 0.1% of 90Sr is released to the atmosphere (air), respectively. On the other hand, the releases of 137Cs are found to be highly dependent on the combustion temperature as well as the nature of vegetation. The releases of 137Cs obtained at 800 °C are 45 ± 7%, 77 ± 9%, 92 ± 5%, and 2.4 ± 0.5% for surface litter and twigs, alder twigs, alder leaves, and organic soil, respectively. The mechanism associated with the high release of 137Cs at a high temperature of 800 °C was explored.


Assuntos
Poluentes Radioativos do Ar/análise , Incineração , Material Particulado/análise , Plantas/química , Monitoramento de Radiação , Atmosfera/química
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