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1.
Plant Physiol Biochem ; 207: 108401, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38301327

RESUMO

The exogenous application of amino acids (AAs) generally alleviates cadmium (Cd) toxicity in plants by altering their subcellular distribution. However, the physiological mechanisms underlying AA-mediated cell wall (CW) sequestration of Cd in Chinese cabbage remain unclear. Using two genotypes of Chinses cabbage, Jingcui 60 (Cd-tolerant) and 16-7 (Cd-sensitive), we characterized the root structure, subcellular distribution of Cd, CW component, and related gene expression under the Cd stress. Cysteine (Cys) supplementation led to a reduction in the Cd concentration in the shoots of Jingcui 60 and 16-7 by 65.09 % and 64.03 %, respectively. Addition of Cys alleviated leaf chlorosis in both cultivars by increasing Cd chelation in the root CW and reducing its distribution in the cytoplasm and organelles. We further demonstrated that Cys supplementation mediated the downregulation of PMEI1 expression and improving the activity of pectin methyl-esterase (PME) by 17.98 % and 25.52 % in both cultivars, respectively, compared to the Cd treatment, resulting in an approximate 12.00 %-14.70 % increase in Cd retention in pectin. In contrast, threonine (Thr) application did not significantly alter Cd distribution in the shoots of either cultivar. Taken together, our results suggest that Cys application reduces Cd root-to-shoot translocation by increasing Cd sequestration in the root CW through the downregulation of pectin methyl-esterification.


Assuntos
Brassica , Poluentes do Solo , Pectinas/metabolismo , Cádmio/metabolismo , Aminoácidos/metabolismo , Esterificação , Brassica/genética , Brassica/metabolismo , Raízes de Plantas/metabolismo , Poluentes do Solo/metabolismo
2.
Exp Brain Res ; 241(1): 221-229, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36463329

RESUMO

Increased spatial processing demands, e.g., working memory loads, which include capacity load and resolution load, may interfere with postural stability. To date, there has been little evidence to demonstrate whether capacity load and resolution load affect postural stability. Therefore, this study manipulated capacity load and resolution load in a spatial working memory task to examine how postural stability is affected. Sixteen healthy young participants were tested in a dual-task paradigm that consisted of a postural task with a tandem Romberg stance and a spatial working memory task with different capacity loads and resolution loads in different sessions. Participants were required to detect a salient change (45° in low resolution) or a subtle change (15° in high resolution) in the bar orientation as a resolution load. Capacity load was manipulated by storing the number of bars, with two bars in low capacity and four in high capacity. The results showed significant interactions between capacity load and resolution load on dual-task effects of sway velocity. In the low-resolution condition, the dual-task effects of anteroposterior and mediolateral sway velocity were significantly lower in the high capacity than in the low capacity, yet no significant differences occurred in the high-resolution load condition. Our results suggest that increased capacity loads interfere with postural stability only in low-resolution loads while dual-tasking.


Assuntos
Cognição , Memória de Curto Prazo , Humanos , Memória Espacial , Carga de Trabalho , Equilíbrio Postural
3.
Psychol Rep ; : 332941221137233, 2022 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-36314269

RESUMO

Previous studies have implied that physical activity profoundly influences interpersonal adaptation. However, this effect and its mechanisms have not been directly verified, especially for adolescents. This study examines the association between physical activity and interpersonal adaptation in adolescents through self-esteem and psychological resilience after the coronavirus disease 2019 (COVID-19) pandemic. Participants included 542 Chinese adolescents (aged 13-18 years; 242 boys and 300 girls). Adolescents in China anonymously completed a series of questionnaires, including the PARS-3 Scale of PE Activity Grade (PARS-3), the Self-esteem Scale (SES), the Resilience Scale for Adolescents (RSCA), and the Interpersonal Adaptation Scale. The results showed that physical activity positively correlated with self-esteem, psychological resilience, and interpersonal adaptation. Additionally, self-esteem and psychological resilience serially mediated the impact of physical activity on interpersonal adaptation. The findings highlight the positive impact of physical activity on adolescent interpersonal adaptation by strengthening positive psychological resources in the post-pandemic era.

4.
Cells ; 10(12)2021 11 30.
Artigo em Inglês | MEDLINE | ID: mdl-34943876

RESUMO

GP.Mur is a clinically important red blood cell (RBC) phenotype in Southeast Asia. The molecular entity of GP.Mur is glycophorin B-A-B hybrid protein that promotes band 3 expression and band 3-AQP1 interaction, and alters the organization of band 3 complexes with Rh/RhAG complexes. GP.Mur+ RBCs are more resistant to osmotic stress. To explore whether GP.Mur+ RBCs could be structurally more resilient, we compared deformability and osmotic fragility of fresh RBCs from 145 adults without major illness (47% GP.Mur). We also evaluated potential impacts of cellular and lipid factors on RBC deformability and osmotic resistivity. Contrary to our anticipation, these two physical properties were independent from each other based on multivariate regression analyses. GP.Mur+ RBCs were less deformable than non-GP.Mur RBCs. We also unexpectedly found 25% microcytosis in GP.Mur+ female subjects (10/40). Both microcytosis and membrane cholesterol reduced deformability, but the latter was only observed in non-GP.Mur and not GP.Mur+ normocytes. The osmotic fragility of erythrocytes was not affected by microcytosis; instead, larger mean corpuscular volume (MCV) increased the chances of hypotonic burst. From comparison with GP.Mur+ RBCs, higher band 3 expression strengthened the structure of RBC membrane and submembranous cytoskeletal networks and thereby reduced cell deformability; stronger band 3-AQP1 interaction additionally supported osmotic resistance. Thus, red cell deformability and osmotic resistivity involve distinct structural-functional roles of band 3.


Assuntos
Proteína 1 de Troca de Ânion do Eritrócito/metabolismo , Deformação Eritrocítica , Eritrócitos/metabolismo , Eritrócitos/patologia , Fragilidade Osmótica , Adulto , Aquaporina 1/metabolismo , Colesterol/sangue , Colesterol/metabolismo , Contagem de Eritrócitos , Membrana Eritrocítica/metabolismo , Humanos , Modelos Biológicos , Análise Multivariada , Ligação Proteica , Análise de Regressão
5.
Memory ; 27(6): 750-757, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-30595083

RESUMO

Stimuli presented with targets in a detection task are later recognised more accurately than those presented with distractors, an unusual effect labelled the attentional boost effect (ABE). This effect may reflect an enhancement triggered by target detection, the inhibition of distractor rejection, or some combination of both. To test these possibilities, the present study adopted a baseline similar to that of Swallow and Jiang ([2014b]. The attentional boost effect really is a boost: evidence from a new baseline. Attention, Perception, & Psychophysics, 76(5), 1298-1307); the goal was to separate target-induced enhancements from distractor-induced inhibition. An R/K procedure was applied to further explore the kind of memory that might be affected by target detection or distractor rejection. The results show that the memory advantage for target-paired words was robust relative to that of baseline words; this advantage was mainly observed in R responses. More importantly, a memory reduction was also observed for distractor-paired words relative to baseline words, though this reduction was only observed in R responses. These data led us to conclude that the ABE was triggered by both processes: target-induced enhancement and distractor-induced inhibition. Moreover, both processes were more likely to affect recollection-based recognition.


Assuntos
Atenção , Inibição Psicológica , Memória , Humanos , Estimulação Luminosa , Reconhecimento Psicológico , Adulto Jovem
6.
J Virol ; 82(13): 6470-80, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18448543

RESUMO

Japanese encephalitis virus (JEV) and dengue virus serotype 2 (DEN-2) are enveloped flaviviruses that enter cells through receptor-mediated endocytosis and low pH-triggered membrane fusion and then replicate in intracellular membrane structures. Lipid rafts, cholesterol-enriched lipid-ordered membrane domains, are platforms for a variety of cellular functions. In this study, we found that disruption of lipid raft formation by cholesterol depletion with methyl-beta-cyclodextrin or cholesterol chelation with filipin III reduces JEV and DEN-2 infection, mainly at the intracellular replication steps and, to a lesser extent, at viral entry. Using a membrane flotation assay, we found that several flaviviral nonstructural proteins are associated with detergent-resistant membrane structures, indicating that the replication complex of JEV and DEN-2 localizes to the membranes that possess the lipid raft property. Interestingly, we also found that addition of cholesterol readily blocks flaviviral infection, a result that contrasts with previous reports of other viruses, such as Sindbis virus, whose infectivity is enhanced by cholesterol. Cholesterol mainly affected the early step of the flavivirus life cycle, because the presence of cholesterol during viral adsorption greatly blocked JEV and DEN-2 infectivity. Flavirial entry, probably at fusion and RNA uncoating steps, was hindered by cholesterol. Our results thus suggest a stringent requirement for membrane components, especially with respect to the amount of cholesterol, in various steps of the flavivirus life cycle.


Assuntos
Colesterol/metabolismo , Flavivirus/fisiologia , Microdomínios da Membrana/metabolismo , Proteínas Virais/metabolismo , Internalização do Vírus/efeitos dos fármacos , Animais , Western Blotting , Linhagem Celular Tumoral , Primers do DNA/genética , Eletroforese em Gel de Ágar , Filipina/metabolismo , Citometria de Fluxo , Camundongos , Microscopia de Fluorescência , Sais de Tetrazólio , beta-Ciclodextrinas/metabolismo
7.
J Clin Virol ; 32(3): 199-217, 2005 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15722025

RESUMO

BACKGROUND: Rotavirus epidemiology information is required for gastroenteritis disease control and prevention. Information gathered about the serotype distribution of rotaviruses isolated in Taiwan is of crucial significance, before a licensed rotavirus vaccine is introduced. OBJECTIVES: The purpose of the present study is to investigate the epidemiological diversity of rotaviruses in Taiwan. STUDY DESIGN: A total of 51 stool samples taken from cases of acute gastroenteritis were collected from three teaching hospitals in central Taiwan in 1996, 2001 and 2002. The samples were subjected to RT-PCR tests of VP7 gene of the human rotavirus group A, B, C. RESULTS: A total of 16 stool samples were detected positive by RT-PCR and 10 were sequence analyzed and classified into G1, G3, and G9 types. Compared with other HRV strains: the sequences of CS96-40 of G1 are similar to MVD9816 (identity rate 97.15% and 96.09%, respectively, from Uruguay); the sequences of CS02-01 of G3 are similar to 98-B31 (identity rate 98.93% and 98.72%, respectively, from Japan); the sequences of CS01-05, CS01-06, CS01-07, CS01-09, CS01-13, CS02-02, CS02-03, CS02-04 are very similar to other established G9 rotaviruses sequences (identity rate 96.85-99.88%), especially between CS02-04 and SP2737 (from Japan) with an identity rate of 99.88% and 100% nucleotide and amino acid, respectively. Except for CS01-06 strain, it is VR3, but not VR5, VR7 or VR8, that found to be the most frequent mutated amino acid regions of VP7 in these strains. CONCLUSIONS: Our findings are the first to document the high prevalence of G9 HRV strains in Taiwan, and suggest the re-emergence of G3 strains in central Taiwan since 1991. Epidemiological surveys carried out in this study suggest genotype shifts from type G1 before 1996, to G9 in 2001 and 2002 and the re-emergence of G3 type in 2002.


Assuntos
Gastroenterite/virologia , Infecções por Rotavirus/epidemiologia , Infecções por Rotavirus/virologia , Rotavirus/classificação , Antígenos Virais/genética , Sequência de Bases , Proteínas do Capsídeo/genética , Criança , DNA Complementar/química , DNA Complementar/isolamento & purificação , DNA Viral , Fezes/virologia , Gastroenterite/epidemiologia , Humanos , Dados de Sequência Molecular , Filogenia , RNA Viral/genética , RNA Viral/isolamento & purificação , RNA Viral/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Rotavirus/genética , Rotavirus/isolamento & purificação , Análise de Sequência de DNA , Homologia de Sequência , Taiwan/epidemiologia
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