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1.
Hum Vaccin Immunother ; 19(2): 2230829, 2023 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-37401618

RESUMO

Affordable, polyvalent meningococcal vaccines are needed for use in emergency reactive immunization campaigns. A phase IV randomized, observer-blind, controlled study compared the safety and immunogenicity of a quadrivalent meningococcal polysaccharide vaccine (MPV-4, MPV ACYW135) and quadrivalent meningococcal ACWY conjugate vaccine (MCV-4, Menactra®). Healthy, 2- to 10-year-old children in Bamako, Mali, were randomized 1:1 to receive one dose of MPV-4 or MCV-4. Safety outcomes were evaluated for 6 months post-immunization. Immunogenicity for all serogroups was assessed for non-inferiority between MPV-4 and MCV-4 30 days post immunization by serum bactericidal antibody assay using baby rabbit complement (rSBA). From December 2020 to July 2021, 260 healthy subjects were consented and randomized. At Day 30 post-immunization, the proportions of subjects with rSBA titers ≥ 128 for all serogroups in the MPV-4 group were non-inferior to those in MCV-4 group. The proportions of subjects with rSBA ≥ 4-fold increase and rSBA titers ≥ 8 for all serogroups were similar among vaccine groups (P > .05). Geometric Mean Titers and Geometric Mean Fold Increases for all serogroups in both vaccine groups were similar (P > .05). Few local and systemic post-immunization reactions of similar severity and duration were observed within 7 days and were similar in both groups (P > .05). All resolved without sequelae. Unsolicited adverse events were similar in both groups regarding relationship to study vaccine, severity and duration. No serious adverse events were reported during the study period. MPV ACYW135 showed a non-inferior immunogenicity profile and a comparable reactogenicity profile to MCV-4 in Malian children aged 2-10 years.Clinical Trial Registration: NCT04450498.


Assuntos
Infecções Meningocócicas , Vacinas Meningocócicas , Neisseria meningitidis , Humanos , Vacinas Conjugadas , Vacinação , Sorogrupo , Anticorpos Antibacterianos , Infecções Meningocócicas/prevenção & controle
2.
Life (Basel) ; 13(5)2023 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-37240849

RESUMO

In clinical practice, Alzheimer's disease (AD), as one of the main neurodegenerative diseases globally, currently has no cure. Recently, the delaying and improving effects of physical exercise on AD have gradually been confirmed; however, the specific mechanism involved needs further clarification. (1) Objective: Explore the mechanism aerobic exercise plays in delaying AD by regulating mitochondrial proteostasis and provide new theoretical bases for improving and delaying AD through aerobic exercise in the future. (2) Methods: Male APP/PS1 mice were randomly divided into a normal group (NG, n = 20), activation group (AG, n = 20), and inhibition group (SG, n = 20). Then, the mice in each group were randomly divided into control group and exercise group (n = 10 mice each), yielding the normal control group (CNG), normal exercise group (ENG), active control group (CAG), active exercise group (EAG), inhibitive control group (CSG), and inhibitive exercise group (ESG). After adaptive training, the mice in the exercise groups were trained on an aerobic treadmill for 12 weeks; we conducted behavioral tests and sampled the results. Then, quantitative real-time PCR (Q-PCR) and Western blot analysis were performed. (3) Results: In the Morris water maze (MWM) test, the latency was significantly reduced and the number of platform crossings was significantly increased in the CAG and ENG compared with the CNG, while the result of the CSG was contrary to this. Compared with the ENG, latency was significantly reduced and the number of platform crossings was significantly increased in the EAG, while the opposite occurred for ESG. Compared with the CAG, the latency was significantly reduced and the number of platform crossings was significantly increased in the EAG, while the results for CSG were contrary. In the step-down test, compared with the CNG, the latency was significantly increased and the number of errors was significantly reduced in the CAG and ENG, respectively, while the results for CSG were contrary. Compared with the ENG, the latency was significantly increased and the number of errors was significantly reduced in the EAG, while the results for ESG were contrary. Compared with the CAG, the latency was significantly increased and the number of errors was significantly reduced in the EAG, while the results for CSG were contrary. Mitochondrial unfolded protein reactions (UPRmt), mitochondrial autophagy, and mitochondrial protein import levels in each group of mice were detected using Q-PCR and Western blot experiments. Compared with the CNG, the UPRmt and mitochondrial autophagy levels in the CAG and ENG were significantly increased and the mitochondrial protein import levels were significantly reduced, while the results for the CSG were contrary. Compared with the ENG, the UPRmt and mitochondrial autophagy levels in the EAG were significantly increased and the mitochondrial protein import levels were significantly reduced, while the results for ESG were contrary. Compared with the CAG, the UPRmt and mitochondrial autophagy levels in the EAG were significantly increased and the mitochondrial protein import levels were significantly reduced, while the results for CSG were contrary. (4) Conclusions: Aerobic exercise can improve cognitive function levels and delay the symptoms of AD in APP/PS1 mice by regulating mitochondrial proteostasis.

3.
Life Sci ; 313: 121284, 2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-36529280

RESUMO

AIMS: Cardiorespiratory fitness (CRF), an important biomarker of human health, is impaired in cold environment compared to thermoneutral condition. The study aimed to investigate the role of metabolome response to acute exercise in regulation of CRF at different ambient temperatures. MAIN METHODS: A total of 27 young adults were recruited, and each subject underwent a cardiopulmonary exercise test (CPET) and a constant load submaximal exercise at both room temperature (25 °C) and cold temperature (0 °C). The serum samples were collected before and immediately after constant load exercise. KEY FINDINGS: Acute cold exposure decreased CRF by 41 %, accompanied by a metabolic shift to anaerobic respiration. It also decreased VO2 and increased respiratory quotient during constant load exercise. Metabolome profiling revealed that acute exercise reprogrammed serum metabolome in an ambient temperature-dependent manner. Specifically, exercise increased a cluster of fatty acids during cold exposure, possibly due to impaired fatty acid oxidation. The correlations between metabolite responses to acute exercise and exercise parameters were analyzed using partial least squares regression and machine learning, revealing that metabolite responses to acute exercise were highly correlated with exercise parameters and predictive of CRF. Among the contributors, tryptophan and its metabolites stood out as important ones. SIGNIFICANCE: These results suggested that the metabolite responses to acute submaximal exercise unmasks the exercise performance at different ambient temperatures, highlighting the role of metabolite orchestration in the physiological regulation of CRF.


Assuntos
Aptidão Cardiorrespiratória , Adulto Jovem , Humanos , Temperatura , Exercício Físico/fisiologia , Teste de Esforço/métodos , Temperatura Baixa , Consumo de Oxigênio/fisiologia
4.
Front Bioeng Biotechnol ; 10: 1043028, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36338127

RESUMO

Maintaining proper hydration is essential for athletes to sustain optimal performance and preserve their physical health. Existing studies have confirmed that urine color is one of the effective indicators for the subjective evaluation of athletes' hydration through the urine color chart. However, the use of urine color charts to evaluate hydration is easily affected by the test environment, urine container and subjective feeling. At present, there are few hydration monitoring instruments based on quantitative analysis of urine color. In recent years, the L*a*b* color model has been widely used in the objective quantitative analysis of color. The L* value represents the luminance change from black to white, the a* value represents the chromaticity change from green to red, and the b* value represents the chromaticity change from blue to yellow. Our previous research has confirmed that the urine color b ∗ value is an effective new indicator to evaluate the hydration of athletes. The research team developed a urine hydration monitoring and rehydration guidance system based on the urine color's L*a*b* parameters via wireless network technology and digital image technology. The hardware structure of the system is composed of a cuvette, a standard light source, a camera, an image collector, a host system, and a touch screen system. The system software is composed of functional modules, such as user information, image acquisition, image processing, and image recognition. The system operation process includes starting the system, filling in basic information, putting the sample, testing the sample, local data review, local data upload, and cloud data review. The system exhibits stable performance, a friendly operation interface, and simple and fast testing. It can objectively and accurately evaluate the hydration of athletes and provide personalized rehydration guidance. The system offers a new method for solving practical problems in sports training, and it has broad application prospects.

5.
Front Nutr ; 9: 997189, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36034925

RESUMO

Objectives: Existing studies have confirmed that urine colour through a urine colour chart is one of the effective indicators for assessing hydration. In recent years, the L*a*b* colour space has been widely used in the objective quantitative analysis of colour. The L*, a* and b* values represent the luminance change from black to white, the chromaticity change from green to red and the chromaticity change from blue to yellow, respectively. This study aimed to examine the validity of the urine colour L*a*b* parameters for assessing the level of hydration amongst athletes. Methods: The study included a total of 474 young elite athletes (251 males and 223 females, age: 24.59 ± 4.86 years). A total of 803 urine samples were collected from the subjects in various stages of hydration, including morning urine and spot urine sample during rehydration. L*a*b* parameters were measured by spectrophotometer. Hydration status was assessed via urine osmolality and urine specific gravity. Results: Urine colour b* value has a high correlation with urine specific gravity and urine osmolality (r = 0.811, 0.741, both p < 0.01); L* value has a moderate correlation with urine specific gravity and urine osmolality (r = -0.508, -0.471, both p < 0.01); there was no significant correlation between a* value and urine specific gravity, urine osmolality (p > 0.05). Whether the diagnosis of hypohydration is based on Usg ≥ 1.020 or Uosm ≥ 700 mmol/kg: The AUC of b* values were all above 0.9 and the specificity and sensitivity of b* values were high (both greater than 80%). The AUC of both L* and a* values were less than 0.5. Whether the diagnosis of hyperhydration is based on Usg ≤ 1.010 or Uosm ≤ 500 mmol/kg: The AUC of b* values were all above 0.9 and the specificity and sensitivity of b* value were high (both greater than 90%). The AUC of both L* and a* values were less than 0.5. Conclusion: These results suggested that the validity of urine colour b* value for assessing hydration amongst athletes was high, however, the validity of urine colour L* and a* values were low.

6.
Artigo em Inglês | MEDLINE | ID: mdl-35742289

RESUMO

The purpose of this study was to investigate the effect of transcranial pulsed current stimulation (tPCS) on fatigue delay after medium-intensity training. Materials and Methods: Ninety healthy college athletes were randomly divided into an experimental group (n = 45) and control group (n = 45). The experimental group received medium-intensity training for a week. After each training, the experimental group received true stimulation of tPCS (continuous 15 min 1.5 mA current intensity stimulation). The control group received sham stimulation. The physiological and biochemical indicators of participants were tested before and after the experiment, and finally 30 participants in each group were included for data analysis. Results: In the experimental group, creatine kinase (CK), cortisol (C), time-domain heart rate variability indices root mean square of the successive differences (RMSSD), standard deviation of normal R-R intervals (SDNN), and frequency domain indicator low frequency (LF) all increased slowly after the intervention. Among these, CK, C, and SDNN values were significantly lower than those in the control group (p < 0.05). Testosterone (T), T/C, and heart rate variability frequency domain indicator high frequency (HF) in the experimental group decreased slowly after the intervention, and the HF value was significantly lower than that in the control group (p < 0.05). The changes in all of the indicators in the experimental group were smaller than those in the control group. Conclusion: The application of tPCS after medium-intensity training enhanced the adaptability to training and had a significant effect on the maintenance of physiological state. The application of tPCS can significantly promote the recovery of autonomic nervous system function, enhance the regulation of parasympathetic nerves, and delay the occurrence of fatigue.


Assuntos
Fadiga , Sistema Nervoso Parassimpático , Atletas , Fadiga/terapia , Frequência Cardíaca/fisiologia , Humanos
7.
Eur J Appl Physiol ; 121(10): 2773-2785, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34148146

RESUMO

PURPOSE: To compare the effects of 12-week high-intensity interval training (HIIT) and vigorous-intensity continuous training (VICT) on cognitive function, physical fitness, VO2max, serum neurotransmitters and neurotrophic factors in overweight and obese elderly individuals. METHODS: Twenty-nine physically inactive older adults (18 males and 11 females) with a mean age of 64.8 ± 3.9 years were randomly divided into a control group (CON, n = 9), an HIIT group (4 × 3 min at 90% VO2max interspersed with 3 min at 60% VO2max, n = 10) and a VICT group (25 min at 70% VO2max, n = 10) and submitted to 12 weeks of training. Cognitive function questionnaires, physical fitness, VO2max, serum neurotransmitters and neurotrophic factors were determined at baseline and post training. RESULTS: Twelve weeks of HIIT and VICT improved the VO2max (4.19 ± 2.21 and 1.84 ± 1.63 mL/kg/min, respectively, p = 0.005), sit-and-reach distance (8.7 ± 3.0 and 7.8 ± 3.8 cm, p = 0.033), choice reaction time (- 0.115 ± 0.15 and - 0.09 ± 0.15 s, p = 0.004) and one-leg stand time (4.4 ± 3.4 and 4.2 ± 4.0 s, p < 0.001) of the elderly participants. The serum concentrations of brain-derived neurotrophic factor (375.5 ± 247.9 and 227.0 ± 137.1 pg/ml, p = 0.006), nerve growth factor (33.9 ± 16.7 and 23.3 ± 14.5 pg/ml, p = 0.037), neurotrophin-3 (24.2 ± 9.33 and 16.3 ± 5.91 pg/ml, p = 0.006) and neurotrophin-4 (10.4 ± 3.8 and 7.8 ± 5.0 pg/ml, p = 0.029) increased significantly in the HIIT and VICT groups after training. In addition, compared to VICT, HIIT significantly increased VO2max and the serum neurotrophin-3 concentration. Serum concentrations of the neurotransmitters acetylcholine, dopamine and serotonin trended upward with training. No significant change was observed in the cognitive function questionnaire scores (p > 0.05). CONCLUSION: HIIT is suitable for elderly adults and is more effective than VICT for improving VO2max and serum neurotrophin-3 concentrations. CHINESE CLINICAL TRIAL REGISTRY NUMBER: No. ChiCTR1900022315, date of registration: 4 April 2019.


Assuntos
Treinamento Intervalado de Alta Intensidade , Fatores de Crescimento Neural/sangue , Obesidade/fisiopatologia , Sobrepeso/fisiopatologia , Idoso , China , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Consumo de Oxigênio/fisiologia , Aptidão Física/fisiologia
8.
Educ Psychol Meas ; 80(2): 293-311, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32158023

RESUMO

The chiropractic clinical competency examination uses groups of items that are integrated by a common case vignette. The nature of the vignette items violates the assumption of local independence for items nested within a vignette. This study examines via simulation a new algorithmic approach for addressing the local independence violation problem using a two-level alternating directions testlet model. Parameter values for item difficulty, discrimination, test-taker ability, and test-taker secondary abilities associated with a particular testlet are generated and parameter recovery through Markov Chain Monte Carlo Bayesian methods and generalized maximum likelihood estimation methods are compared. To aid with the complex computational efforts, the novel so-called TensorFlow platform is used. Both estimation methods provided satisfactory parameter recovery, although the Bayesian methods were found to be somewhat superior in recovering item discrimination parameters. The practical significance of the results are discussed in relation to obtaining accurate estimates of item, test, ability parameters, and measurement reliability information.

10.
J Cell Sci ; 127(Pt 8): 1631-9, 2014 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-24554434

RESUMO

Centrosome cohesion, mostly regarded as a proteinaceous linker between parental centrioles, ensures that the interphase centrosome(s) function as a single microtubule-organizing center. Impairment of centrosome cohesion leads to the splitting of centrosomes. Although the list of cohesion proteins is growing, the precise composition and regulation of centrosome cohesion are still largely unknown. In this study, we show that the centriolar protein centlein (also known as CNTLN) localizes to the proximal ends of the centrioles and directly interacts with both C-Nap1 (also known as Cep250) and Cep68. Moreover, centlein complexes with C-Nap1 and Cep68 at the proximal ends of centrioles during interphase and functions as a molecular link between C-Nap1 and Cep68. Depletion of centlein impairs recruitment of Cep68 to the centrosomes and, in turn, results in centrosome splitting. Both centlein and Cep68 are novel Nek2A substrates. Collectively, our data demonstrate that centrosome cohesion is maintained by the newly identified complex of C-Nap1-centlein-Cep68.


Assuntos
Proteínas de Ciclo Celular/metabolismo , Proteínas de Ciclo Celular/fisiologia , Centríolos/metabolismo , Proteínas Associadas aos Microtúbulos/metabolismo , Proteínas Nucleares/metabolismo , Animais , Ciclo Celular , Centrossomo/metabolismo , Proteínas Cromossômicas não Histona , Células HEK293 , Células HeLa , Humanos , Camundongos , Quinases Relacionadas a NIMA , Proteínas de Ligação a Poli-ADP-Ribose , Mapeamento de Interação de Proteínas , Proteínas Serina-Treonina Quinases/metabolismo , Transporte Proteico , Ratos
11.
IEEE Trans Syst Man Cybern B Cybern ; 42(3): 889-99, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22275719

RESUMO

Human segmentation in photo images is a challenging and important problem that finds numerous applications ranging from album making and photo classification to image retrieval. Previous works on human segmentation usually demand a time-consuming training phase for complex shape-matching processes. In this paper, we propose a straightforward framework to automatically recover human bodies from color photos. Employing a coarse-to-fine strategy, we first detect a coarse torso (CT) using the multicue CT detection algorithm and then extract the accurate region of the upper body. Then, an iterative multiple oblique histogram algorithm is presented to accurately recover the lower body based on human kinematics. The performance of our algorithm is evaluated on our own data set (contains 197 images with human body region ground truth data), VOC 2006, and the 2010 data set. Experimental results demonstrate the merits of the proposed method in segmenting a person with various poses.


Assuntos
Algoritmos , Inteligência Artificial , Biometria/métodos , Interpretação de Imagem Assistida por Computador/métodos , Reconhecimento Automatizado de Padrão/métodos , Fotografação/métodos , Imagem Corporal Total/métodos , Humanos
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