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1.
Front Sports Act Living ; 6: 1297821, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38756188

RESUMO

Introduction: Implementing a self-refereeing system presents a unique challenge in sports education, particularly in academic and training settings where officiated sports prevail. However, Ultimate Frisbee stands out by entrusting players with both athlete and referee roles, introducing distinctive ethical complexities. This manuscript is intended to evaluate ethical behavior and self-control within the Spirit of the Game (SOTG) scoring system in Elite Ultimate. To address these, Ultimate employs the (SOTG) scoring system, integral since the sport's inception in the late 1980s. SOTG aims to enhance and evaluate athletes' ethical conduct. This study evaluates SOTG's effectiveness in elite-level Ultimate, analyzing variations across divisions and age groups in three high-level tournaments. Methods: Using a cross-sectional design, data were collected from five international Ultimate tournaments in 2022. Teams spanned diverse age groups (under 17 to over 50) and divisions (women's, mixed, open). Post-match, teams assessed opponents' SOTG in five domains: Rules knowledge, fouls, fairness, attitude/self-control, and communication. Ratings used a 5-point Likert scale ("poor" to "excellent"). An overall SOTG score was calculated by aggregating domain scores. Results: Our study consistently revealed high SOTG scores, reflecting strong sportsmanship. "Positive attitude and self-control" consistently ranked highest, while "Knowledge and use of the rules" scored lowest. Divisional differences in SOTG were statistically insignificant. Notably, WMUCC2022 (participants aged 30+) had significantly higher SOTG scores, possibly indicating age-related self-control improvement or evolving sport culture. Lower rules knowledge scores may stem from linguistic translation challenges. Conclusion: Self-refereeing promotes ethical behavior across divisions and age groups. SOTG underscores sportsmanship's importance and aligns with International Olympic Committee (IOC) and with Sustainable Development Goals (SDGs), particularly SDG 3, 4, 5 and 16 fostering a fairer, healthier, and more peaceful world.

2.
Brain Res ; 1825: 148729, 2024 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-38128810

RESUMO

Total sleep deprivation (TSD) negatively affects cognitive functions, especially vigilance attention, but studies on vigilance changes in terms of electroencephalography (EEG) microstates after TSD are limited. This study investigates the impact of TSD on vigilance attention, EEG microstates and its relationship. Thirty healthy adult males completed a psychomotor vigilance task (PVT) before, 24 h after, and 36 h after TSD while their EEG was recorded during rest. Microstate analysis revealed significant changes in the occurrence and contribution of microstate class B after TSD. Moreover, changes in the probability of transitioning between microstate classes A and D were observed, correlating with decreased vigilance. Specifically, a positive correlation was found between transitioning from class B to class C and vigilance, while a trend of negative correlation was observed between transitioning between classes A and D and vigilance. These findings indicate abnormal activity in the salience network and dorsal attention network following sleep deprivation. TSD impairs vigilance attention, as demonstrated by the effects on EEG microstate class B and the transitions between classes A and D. The study suggests its potential as an early warning indicator for predicting vigilance attention after sleep deprivation.


Assuntos
Eletroencefalografia , Privação do Sono , Adulto , Masculino , Humanos , Privação do Sono/complicações , Vigília , Cognição , Descanso , Encéfalo
3.
Brain Sci ; 13(10)2023 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-37891837

RESUMO

The impact of sleep deprivation on working memory can only be reversed by recovery sleep (RS). However, there are limited electrophysiological studies on the effect of RS on the improvement in working memory after sleep deprivation, and the changes in the early components of event-related potentials (ERPs) before and after RS are still unclear. Therefore, this study aims to explore the effects of RS on the earlier ERP components related to object working memory following 36 h of total sleep deprivation (TSD). Twenty healthy male participants performed an object working memory task after 36 h of TSD and after 8 h of RS. Electroencephalogram data were recorded accordingly while the task was performed. Repeated ANOVA showed that P2 amplitudes related to object working memory decreased significantly after 8 h of RS compared to after a 36 h period of TSD, but there was no significant difference from baseline (BS), which indicates a trend of recovery to the baseline state. An 8 h RS can partially improve impaired object working memory caused by TSD. However, a longer period of RS is needed for the complete recovery of cognitive function after a long period of TSD.

4.
Psychol Sport Exerc ; 65: 102320, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-37665825

RESUMO

For elite performers, psychomotor behavior's success or failure can be traced to differences in brain dynamics. The psychomotor efficiency hypothesis suggests refined cortical activity through 1) selective activation of task-relevant processes and 2) inhibition of non-essential processes. The use of electroencephalography (EEG) has been applied to investigate psychomotor performance's neural processes. The EEG markers that reflect an elevation of psychomotor efficiency include left temporal alpha (T3 alpha), frontal midline theta (Fm theta), sensorimotor rhythm (SMR), and the coherence between frontal and left temporal regions. However, the relationship between elite performers' task-relevant and non-essential neural processes is still not well understood. Therefore, this study aimed to explore how each task-relevant and inhibition of non-essential processes contribute to superior psychomotor behavior. Thirty-five highly skilled marksmen were recruited to perform 30 shots in the shooting task while the EEG was recorded. The marksmen were divided into two groups (superior & inferior) based on a median split of shooting performance. The superior group exhibited higher accuracy and precision, with a reduction in movement jerk. EEG measures revealed that the superior group exhibited higher SMR before the trigger pull than the inferior group. In addition, the superior group demonstrated reduced Fz-T3 coherence in their bull's eye shots than the missed shots. These results suggest that the superior group exhibited less effortful engagement of task-relevant processes and lower interference from non-essential cortical regions than the inferior group. The study's overall findings support the psychomotor efficiency hypothesis. When comparing highly skilled performers, the slight differences in brain dynamics ultimately contribute to the success or failure of psychomotor performance.


Assuntos
Encéfalo , Gastrópodes , Animais , Eletroencefalografia , Inibição Psicológica , Movimento
5.
Behav Sci (Basel) ; 13(1)2023 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-36661637

RESUMO

A major concern voiced by motor behavior scientists is to find useful practice techniques that can be effective in improving motor learning and performance. Neurofeedback and self-controlled practice are among the techniques that have recently drawn attention from specialists in this area. The present study examined the additive and individual effects of sensorimotor rhythm (SMR) neurofeedback as well as self-controlled practice on motor learning and performance in novice golfers. In this semi-empirical study, forty adults (20 females, Meanage = 26.10, SD = 5.56 years) were conveniently selected and randomly assigned to four groups: (1) neurofeedback/self-controlled practice, (2) neurofeedback/yoked practice, (3) sham/self-controlled practice, and (4) sham/yoked practice. The participants performed golf putting task in four stages, namely pretest (12 trials), intervention (one day after pretest; 6 sessions, 36 trails each), post-test (one day after intervention; 12 trials), and follow-up (two weeks after interventions; 12 trials). In addition, the participants had their EEG (SMR wave in Cz point) recorded during pretest, post-test, and follow-up. The results indicated that, although no additive effect was observed for the two practices during different stages of the experiment (p > 0.05), in acquisition and post-test stages, SMR neurofeedback and self-controlled practice independently facilitated golf putting (p ≤ 0.05). However, in the follow-up test, only the neurofeedback practice maintained its positive effects (p ≤ 0.05). The results also showed that participation in SMR neurofeedback practice can enhance the power of the SMR wave (p ≤ 0.05), regardless of the type of the self-controlled practice used. In sum, the two practice techniques seem to be independently effective in facilitating motor learning in instructional settings, particularly for golfers.

6.
Front Psychol ; 14: 1273186, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38187413

RESUMO

Introduction: Achieving optimal visuomotor performance in precision sports relies on maintaining an optimal psychological state during motor preparation. To uncover the optimal psychological state, extensive EEG studies have established a link between the Mu rhythm (8-13 Hz at Cz) and cognitive resource allocation during visuomotor tasks (i.e., golf or shooting). In addition, the new approach in EEG neurofeedback training (NFT), called the function-specific instruction (FSI) approach, for sports involves providing function-directed verbal instructions to assist individuals to control specific EEG parameters and align them with targeted brain activity features. While this approach was initially hypothesized to aid individuals in attaining a particular mental state during NFT, the impact of EEG-NFT involving Mu rhythm on visuomotor performance, especially when contrasting the traditional instruction (TI) approach with the FSI approach, underscores the necessity for additional exploration. Hence, the objective of this study is to investigate the impact of the FSI approach on modulating Mu rhythm through EEG-NFT in the context of visuomotor performance. Methods: Thirty novice participants were recruited and divided into three groups: function-specific instruction (FSI, four females, six males; mean age = 27.00 ± 7.13), traditional instruction (TI, five females, five males; mean age = 27.00 ± 3.88), and sham control (SC, five females, five males; mean age = 27.80 ± 5.34). These groups engaged in a single-session EEG-NFT and performed golf putting tasks both before and after the EEG-NFT. Results: The results showed that within the FSI group, single-session NFT with augmented Mu power led to a significant decrease in putting performance (p = 0.013). Furthermore, we noted a marginal significance indicating a slight increase in Mu power and a reduction in the subjective sensation of action control following EEG-NFT (p = 0.119). While there was a positive correlation between Mu power and mean radial error in golf putting performance (p = 0.043), it is important to interpret this relationship cautiously in the context of reduced accuracy in golf putting. Discussion: The findings emphasize the necessity for extended investigation to attain a more profound comprehension of the nuanced significance of Mu power in visuomotor performance. The study highlights the potential effectiveness of the FSI approach in EEG-NFT and in enhancing visuomotor performance, but it also emphasizes the potential impact of skill level and attentional control, particularly in complex visuomotor tasks.

7.
Polymers (Basel) ; 14(9)2022 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-35567092

RESUMO

BACKGROUND: In vitro three-dimensional (3D) hepatic spheroid culture has shown great promise in toxicity testing because it better mimics the cell-cell and cell-matrix interactions found in in vivo conditions than that of the traditional two-dimensional (2D) culture. Despite embedding HepaRG spheroids with collagen type I (collagen I) extracellular matrix (ECM) revealed a much better differentiation capability, almost all the collagen utilized in in vitro hepatocytes cultures is animal-derived collagen that may limit its use in human toxicity testing. METHOD: Here, a preliminary investigation of HepaRG cells cultured in different dimensionalities and with the addition of ECM was performed. Comparisons of conventional 2D culture with 3D spheroid culture were performed based on their functional or structural differences over 7 days. Rat tail collagen (rtCollagen) I and recombinant human collagen (rhCollagen) I were investigated for their ability in promoting HepaRG spheroid differentiation. RESULTS: An immunofluorescence analysis of the hepatocyte-specific functional protein albumin suggested that HepaRG spheroids demonstrated better hepatic function than spheroids from 2D culture, and the function of HepaRG spheroids improved in a time-dependent manner. The fluorescence intensities per unit area of spheroids formed by 1000 cells on days 7 and 10 were 25.41 and 45.38, respectively, whereas almost undetectable fluorescence was obtained with 2D cells. In addition, the embedding of HepaRG spheroids into rtCollagen and rhCollagen I showed that HepaRG differentiation can be accelerated relative to the differentiation of spheroids grown in suspension, demonstrating the great promise of HepaRG spheroids. CONCLUSIONS: The culture conditions established in this study provide a potentially novel alternative for promoting the differentiation of HepaRG spheroids into mature hepatocytes through a collagen-embedded in vitro liver spheroid model. This culture method is envisioned to provide insights for future drug toxicology.

8.
Zool Res ; 43(1): 129-146, 2022 01 18.
Artigo em Inglês | MEDLINE | ID: mdl-34939375

RESUMO

The Hengduan Mountains Region (HMR) is the largest "evolutionary frontier" of the northern temperate zone, and the origin and maintenance of species in this area is a research hotspot. Exploring species-specific responses to historical and contemporary environmental changes will improve our understanding of the role of this region in maintaining biodiversity. In this study, mitochondrial and microsatellite diversities were used to assess the contributions of paleogeological events, Pleistocene climatic oscillations, and contemporary landscape characteristics to the rapid intraspecific diversification of Liangshantriton taliangensis, a vulnerable amphibian species endemic to several sky-island mountains in the southeastern HMR. Divergence date estimations suggested that the East Asian monsoon, local uplifting events (Xigeda Formation strata), and Early-Middle Pleistocene transition (EMPT) promoted rapid divergence of L. taliangensis during the Pleistocene, yielding eight mitochondrial lineages and six nuclear genetic lineages. Moreover, population genetic structures were mainly fixed through isolation by resistance. Multiple in situ refugia were identified by ecological niche models and high genetic diversity, which played crucial roles in the persistence and divergence of L. taliangensis during glacial-interglacial cycles. Dramatic climatic fluctuations further promoted recurrent isolation and admixing of populations in scattered glacial refugia. The apparent mitonuclear discordance was likely the result of introgression by secondary contact and/or female-biased dispersal. Postglacial expansion generated two major secondary contact zones (Ganluo (GL) and Chuhongjue (CHJ)). Identification of conservation management units and dispersal corridors offers important recommendations for the conservation of this species.


Assuntos
Evolução Molecular , Variação Genética , Salamandridae , Animais , DNA Mitocondrial/genética , Feminino , Repetições de Microssatélites/genética , Filogenia , Filogeografia , Salamandridae/genética
9.
Front Cell Infect Microbiol ; 11: 706919, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34290994

RESUMO

Zinc finger and BTB domain containing 1(Zbtb1) is a transcriptional suppressor protein, and a member of the mammalian Zbtb gene family. Previous studies have shown that Zbtb1 is essential for T-cell development. However, the role of Zbtb1 in T-cell lymphoma is undetermined. In this study, an EL4 cell line with Zbtb1 deletion was constructed using the CRISPR-Cas9 technique. The expression profiles of microRNA and circRNA produced by the control and gene deletion groups were determined by RNA-seq. In general, 24 differentially expressed microRNA and 16 differentially expressed circRNA were found between normal group and gene deletion group. Through further analysis of differentially expressed genes, GO term histogram and KEGG scatter plot were drawn, and three pairs of miRNA and circRNA regulatory relationships were found. This study describes the differentially expressed microRNA and circRNA in normal and Zbtb1-deficient EL4 cell lines, thus providing potential targets for drug development and clinical treatment of T-cell lymphoma.


Assuntos
Linfoma de Células T/genética , MicroRNAs , RNA Circular , Proteínas Repressoras/genética , Animais , Diferenciação Celular , Linhagem Celular , Perfilação da Expressão Gênica , Técnicas de Inativação de Genes , Camundongos , MicroRNAs/genética , RNA Circular/genética
11.
Sci Rep ; 11(1): 8457, 2021 04 19.
Artigo em Inglês | MEDLINE | ID: mdl-33875729

RESUMO

Transcranial direct current stimulation (tDCS) is a promising tool to enhance cognitive performance. However, its effectiveness has not yet been unequivocally shown. Thus, here we tested whether coupling tDCS with a bout of aerobic exercise (AE) is more effective in modulating cognitive functions than tDCS or AE alone. One hundred twenty-two healthy participants were assigned to five randomized controlled crossover experiments. Two multimodal target experiments (EXP-4: anodal vs. sham tDCS during AE; EXP-5: cathodal vs. sham tDCS during AE) investigated whether anodal (a-tDCS) or cathodal tDCS (c-tDCS) applied during AE over the left dorsolateral prefrontal cortex (left DLPFC) affects executive functioning (inhibition ability). In three unimodal control experiments, the participants were either stimulated (EXP-1: anodal vs. sham tDCS, EXP-2: cathodal vs. sham tDCS) or did AE (EXP-3: AE vs. active control). Participants performed an Eriksen flanker task during ergometer cycling at moderate intensity (in EXP. 3-5). Only c-tDCS during AE had a significant adverse effect on the inhibition task, with decreased accuracy. This outcome provides preliminary evidence that c-tDCS during AE over the left DLPFC might effectively modulate inhibition performance compared to c-tDCS alone. However, more systematic research is needed in the future.


Assuntos
Cognição/fisiologia , Função Executiva/fisiologia , Exercício Físico , Córtex Pré-Frontal/fisiologia , Estimulação Transcraniana por Corrente Contínua/métodos , Adulto , Estudos Cross-Over , Feminino , Voluntários Saudáveis , Humanos , Masculino , Adulto Jovem
12.
Front Psychol ; 12: 633228, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33664700

RESUMO

The meshed control theory assumes that cognitive control and automatic processes work together in the natural attention of experts for superior performance. However, the methods adopted by previous studies limit their capacity to provide in-depth information on the neuromotor processes. This experiment tested the theory with an alternative approach. Twelve skilled golfers were recruited to perform a putting task under three conditions: (1) normal condition, with no focus instruction (NC), (2) external focus of attention condition (EC), and (3) internal focus of attention condition (IC). Four blocks of 10 putts each were performed under each condition. The putting success rate and accuracy were measured and electroencephalographies (EEGs) were recorded. The behavioral results showed that the NC produced a higher putting success rate and accuracy than the EC and IC. The EEG data showed that the skilled golfers' attentional processes in the NC initially resembled those in the EC and then moved toward those in the IC just before putting. This indicates a switch from more automatic processes to cognitive control processes while preparing to putt. The findings offer support for the meshed control theory and indicate the dynamic nature of neuromotor processes for the superior performance of athletes in challenging situations.

13.
Front Microbiol ; 11: 607735, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33391230

RESUMO

Lactic acid bacteria (LAB) are the primary genera of the intestinal flora and have many probiotic functions. In the present study, Lactobacillus rhamnosus GG (LGG) ATCC 53103 was used to treat BALB/c mice. After LGG intervention, both low and high LGG doses were shown to improve the observed OTU, Chao1, ACE, and Shannon indices, while the Simpson index decreased, demonstrating that LGG can promote intestinal microbiota abundance and diversity. Furthermore, LGG treatment increased the abundances of intestinal Firmicutes, Bacteroides and Actinomycetes while reducing that of Proteobacteria. In addition to its effect on gut the microbiota, LGG could also regulate the host immune system. In the present study, we showed that LGG could affect the percentage of CD3+ T lymphocytes in the spleens (SPLs), mesenteric lymph nodes (MLNs), Peyer's patches (PPs) and lamina propria lymphocytes (LPLs) of mice, including total CD3+ T, CD3+CD4+ T, and CD3+CD8+ T lymphocytes. Furthermore, LGG could effectively increase the expression of Th1-type cytokines (IFN-γ) and Th2 cytokines (IL-4) in CD4+ T cells, indicating that the proportion of Th1 and Th2 cells in mice with LGG treatment was in a high equilibrium state compared to the control group. In addition, the IFN-γ/IL-4 ratio was greater than 1 in mice with LGG intervention, suggesting that LGG tends to mediate the Th1 immune response. The results of the present study also showed that LGG upregulated the expression of IL-17 in CD4+ T cells and regulated the percentage of CD4+CD25+Foxp3+ Treg cells in various secondary immunological organs, indicating that LGG may promote the balance of Th-17 and Treg cells.

14.
PeerJ ; 7: e6777, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31086733

RESUMO

BACKGROUND: The efficacy of emotional and motivational regulation can determine athletic performance. Giving the short duration and fast changing nature of emotions experienced by athletes in competition, it is important to examine the temporal dynamics of emotional and motivational regulation. The aim of this study was to investigate emotional and motivational regulation as measured by frontal alpha asymmetry in skilled golfers during putting performance after a performance failure. METHODS: Twenty skilled university golfers were recruited and requested to perform 40 putts at an individualized difficulty level of 40-60% successful putting rate. Trials immediately after a failed putt were selected for analysis. Successful performances were those trials where a hole was and unsuccessful performances were those that failed. The frontal alpha asymmetry index of LnF4-LnF3 was derived for statistical analysis. RESULTS: (1) Successful performance was preceded by a larger frontal alpha asymmetry index at T2 than that of T1, and (2) a larger frontal alpha asymmetry index was observed for unsuccessful performance than for successful performance at T1. DISCUSSION: The results suggest that successful emotional and motivational regulation was characterized by a progressive increase of frontal alpha asymmetry, which led to subsequent putting success when facing an emotionally provocative putting failure. These findings shed light on the application of frontal alpha asymmetry for the understanding and enhancement of emotional and motivational regulation during sport performance.

15.
Biol Psychol ; 110: 212-8, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26277266

RESUMO

Previous evidence suggests that augmented sensorimotor rhythm (SMR) activity is related to the superior regulation of processing cognitive-motor information in motor performance. However, no published studies have examined the relationship between SMR and performance in precision sports; thus, this study examined the relationship between SMR activity and the level of skilled performance in tasks requiring high levels of attention (e.g., dart throwing). We hypothesized that skilled performance would be associated with higher SMR activity. Fourteen dart-throwing experts and eleven novices were recruited. Participants were requested to perform 60 dart throws while EEG was recorded. The 2(Group: Expert, Novice)×2(Time window: -2000 ms to -1000 ms, -1000 ms to 0 ms) ANOVA showed that the dart-throwing experts maintained a relatively higher SMR power than the novices before dart release. These results suggest that SMR might reflect the adaptive regulation of cognitive-motor processing during the preparatory period.


Assuntos
Atletas/psicologia , Desempenho Atlético/psicologia , Jogos Recreativos/psicologia , Desempenho Psicomotor/fisiologia , Adulto , Atenção/fisiologia , Feminino , Humanos , Masculino , Adulto Jovem
16.
J Sport Exerc Psychol ; 37(6): 626-36, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26866770

RESUMO

Sensorimotor rhythm (SMR) activity has been related to automaticity during skilled action execution. However, few studies have bridged the causal link between SMR activity and sports performance. This study investigated the effect of SMR neurofeedback training (SMR NFT) on golf putting performance. We hypothesized that preelite golfers would exhibit enhanced putting performance after SMR NFT. Sixteen preelite golfers were recruited and randomly assigned into either an SMR or a control group. Participants were asked to perform putting while electroencephalogram (EEG) was recorded, both before and after intervention. Our results showed that the SMR group performed more accurately when putting and exhibited greater SMR power than the control group after 8 intervention sessions. This study concludes that SMR NFT is effective for increasing SMR during action preparation and for enhancing golf putting performance. Moreover, greater SMR activity might be an EEG signature of improved attention processing, which induces superior putting performance.


Assuntos
Desempenho Atlético/fisiologia , Retroalimentação Sensorial , Golfe/fisiologia , Neurorretroalimentação , Eletroencefalografia , Retroalimentação Sensorial/fisiologia , Feminino , Humanos , Masculino , Neurorretroalimentação/fisiologia , Adulto Jovem
17.
ISA Trans ; 53(2): 444-53, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24206776

RESUMO

Due to issues such as limited space, it is difficult if it is not impossible to employ a position sensor in the drive control of high-speed micro PMSMs. In order to alleviate this problem, this paper analyzes and implements a simple and robust position sensorless field-oriented control method of high-speed micro PMSMs based on the sliding-mode observer. In particular, the angular position and velocity of the rotor of the high-speed micro PMSM are estimated using the sliding-mode observer. This observer is able to accurately estimate rotor position in the low speed region and guarantee fast convergence of the observer in the high speed region. The proposed position sensorless control method is suitable for electric dental handpiece motor drives where a wide speed range operation is essential. The proposed sensorless FOC method is implemented using a cost-effective 16-bit microcontroller and tested in a prototype electric dental handpiece motor. Several experiments are performed to verify the effectiveness of the proposed method.


Assuntos
Instrumentos Odontológicos , Imãs , Algoritmos , Simulação por Computador , Eletrônica , Desenho de Equipamento , Magnetismo , Modelos Estatísticos
18.
Chinese Journal of Cardiology ; (12): 236-239, 2008.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-243807

RESUMO

<p><b>OBJECTIVE</b>To evaluate the significance of cardiac output (CO) response against exercise determined by IGR method and LVEF, 6 MWT distance in patients with chronic heart failure (CHF).</p><p><b>METHOD</b>To adopt 6 MWT, and before and after the test measuring the CO by the IGR method, furthermore, measure LVEF to 36 patients (heart failure group) with CHF, compare with the health groups (control group).</p><p><b>RESULTS</b>The 6MWT distance of heart failure group (333.00 +/- 49.64) m decrease compared with the control group (582.56 +/- 67.97) m (P < 0.01), moreover, the distance of NYHA class III (314.82 +/- 36.27) m is significantly shorter than II (361.57 +/- 55.42) m (P < 0.05). The LVEF of heart failure group (47.0 +/- 0.4)% reduce compared with the control group (66.9 +/- 5.2)% (P < 0.01), and the data of NYHA class III (43.3 +/- 10.3)% is significantly lower than II (52.8 +/- 7.6)% (P < 0.01). The increase in CO response against exercise of heart failure group (5.97 +/- 1.89) L/min decrease compared with control group (8.88 +/- 0.52) L/min (P < 0.01), furthermore, the value of NYHA class III (5.31 +/- 1.52) L/min, compared with II (7.01 +/- 1.98)L/min, is obviously lower (P < 0.01). The 6MWT distance correlates positively with the increase in CO response against exercise (r = 0.63, P < 0.01), but the correlation is not found between the increase CO response against exercise and the LVEF (r = 0.11, P > 0.05).</p><p><b>CONCLUSION</b>Our results show that CO response against exercise measured by IGR method, with the advantages of being noninvasive, safe, convenient and accurate, combining with the 6MWT can evaluate cardiac reserve in patient with CHF.</p>


Assuntos
Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Débito Cardíaco , Estudos de Casos e Controles , Doença Crônica , Teste de Esforço , Tolerância ao Exercício , Insuficiência Cardíaca , Diagnóstico , Caminhada
19.
Chinese Journal of Cardiology ; (12): 411-414, 2006.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-295305

RESUMO

<p><b>OBJECTIVE</b>Abnormalities in dopamine production and receptor function have been described in human essential hypertension and rodent models of genetic hypertension. We investigated the role of G protein kinase (GRK) 4gamma in essential hypertension in GRK4gamma mutant A142V transgenic mice.</p><p><b>METHODS</b>Blood pressure, renal sodium excretion, D(1) receptor protein expression and phosphorylation were measured in GRK4gammaA142V transgenic mice and control mice. Moreover, the effects of GRK4 inhibition by antisense oligonucleotides on D(1) receptor expressions were determined in HK-2 cells.</p><p><b>RESULTS</b>As compared with their control mice, GRK4gammaA142V transgenic mice had higher blood pressure, lower D(1) receptor expression (0.6 +/- 0.2 vs. 1.5 +/- 0.2, P < 0.05), higher D(1) receptor phosphorylation [(65 +/- 7) DU vs. (35 +/- 7) DU, P < 0.05] in renal cortical membranes and the diuretic and natriuretic effects after stimulation of renal D(1) receptor were impaired in GRK4gammaA142V transgenic mice. Inhibition of GRK4 expression (0.60 +/- 0.10 vs. 1.30 +/- 0.09, P < 0.05) by GRK4 antisense oligonucleotides upregulated D(1) receptor expression (1.5 +/- 0.2 vs. 0.8 +/- 0.1, P < 0.05) in HK-2 cells.</p><p><b>CONCLUSIONS</b>Our results show that GRK4gammaA142V overexpression induced hypertension is mediated by dowregulated renal D(1) receptor expressions in GRK4gammaA142V transgenic mice.</p>


Assuntos
Animais , Feminino , Masculino , Camundongos , Pressão Sanguínea , Regulação para Baixo , Quinase 4 de Receptor Acoplado a Proteína G , Genética , Metabolismo , Regulação da Expressão Gênica , Hipertensão , Genética , Metabolismo , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Oligonucleotídeos Antissenso , Fosforilação , Receptores de Dopamina D1 , Metabolismo
20.
Acta Physiologica Sinica ; (6): 165-170, 2002.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-279318

RESUMO

Proliferation of vascular smooth muscle cells (VSMCs) is often accompanied by changes in intracellular actin distribution. The changes are controlled by the signal transduction pathways of protein kinase C/mitogenic activated protein kinase (PKC-MAPK), but the mechanism is unclear. In order to study the effect of insulin on the intracellular signal transduction (PKC-MAPK) probably involved in the modulation of proliferation and redistribution of actins in the VSMCs, the DNA synthesis, MAPK activities and its gene expression, and the redistribution of intracellular actins were investigated in the isolated VSMCs of SHR pretreated with PKC inhibitor and/or insulin, respectively. We found that insulin treatment resulted in proliferation of the VSMCs and an increase in [(3)H] TdR incorporation. Meanwhile, the activities and expression of MAPK increased significantly compared to the control group. These effects of insulin were blocked by PKC inhibitor. In addition, insulin caused a redistribution of the intracellular actins in VSMCs, which was also inhibited by PKC inhibitor. It is, therefore, suggested that these effects of insulin on VSMCs proliferation and distribution of the intracellular actins may be mediated by the MAPK signal transduction pathway.


Assuntos
Animais , Ratos , Actinas , Metabolismo , Divisão Celular , Técnicas In Vitro , Insulina , Farmacologia , Proteínas Quinases Ativadas por Mitógeno , Fisiologia , Músculo Liso Vascular , Biologia Celular , Miócitos de Músculo Liso , Metabolismo , Proteína Quinase C , Fisiologia , Ratos Endogâmicos SHR , Distribuição Tecidual
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