RESUMO
Cystic fibrosis (CF) is a progressive multiorgan autosomal recessive disease with devastating impact on the lungs caused by derangements of the CF transmembrane conductance regulator (CFTR) gene. Morbidity and mortality are caused by the triad of impaired mucociliary clearance, microbial infections and chronic inflammation. Pseudomonas aeruginosa is the main respiratory pathogen in individuals with CF infecting most patients in later stages. Despite its recognized clinical impact, molecular mechanisms that underlie P. aeruginosa pathogenesis and the host response to P. aeruginosa infection remain incompletely understood. The nuclear hormone receptor peroxisome proliferator-activated receptor (PPAR) γ (PPARγ), has shown to be reduced in CF airways. In the present study, we sought to investigate the upstream mechanisms repressing PPARγ expression and its impact on airway epithelial host defense. Endoplasmic reticulum-stress (ER-stress) triggered unfolded protein response (UPR) activated by misfolded CFTR and P. aeruginosa infection contributed to attenuated expression of PPARγ. Specifically, the protein kinase RNA (PKR)-like ER kinase (PERK) signaling pathway led to the enhanced expression of the CCAAT-enhancer-binding-protein homologous protein (CHOP). CHOP induction led to the repression of PPARγ expression. Mechanistically, we showed that CHOP induction mediated PPARγ attenuation, impacted the innate immune function of normal and ∆F508 primary airway epithelial cells by reducing expression of antimicrobial peptide (AMP) and paraoxanse-2 (PON-2), as well as enhancing IL-8 expression. Furthermore, mitochondrial reactive oxygen species production (mt-ROS) and ER-stress positive feedforward loop also dysregulated mitochondrial bioenergetics. Additionally, our findings implicate that PPARγ agonist pioglitazone (PIO) has beneficial effect on the host at the multicellular level ranging from host defense to mitochondrial re-energization.
Assuntos
Fibrose Cística/metabolismo , PPAR gama/metabolismo , Infecções por Pseudomonas/metabolismo , Pseudomonas aeruginosa/fisiologia , Resposta a Proteínas não Dobradas , Células A549 , Arildialquilfosfatase/metabolismo , Fibrose Cística/complicações , Fibrose Cística/microbiologia , Estresse do Retículo Endoplasmático , Células Epiteliais/metabolismo , Interações Hospedeiro-Patógeno , Humanos , Imunidade Inata , Interleucina-8/metabolismo , Mitocôndrias/metabolismo , PPAR gama/agonistas , Pioglitazona , Infecções por Pseudomonas/imunologia , Fator de Transcrição CHOP/metabolismo , beta-Defensinas/metabolismoRESUMO
Badminton atypical actions and hitting movements often occur during the game; therefore, many special footwork methods have been developed to facilitate the rapid movements required to hit the shuttlecock, including quick turning and jumping and quick directional change movements. Studies have shown that the majority of badminton sport injuries occur in the lower extremity joints of athletes. The purpose of this study was to investigate the influences of hitting motion and unanticipated hitting direction on landing mechanics after backhand lateral jump smashing and landing to analyze joint stiffness and torque changes in three lower extremity joints. Recruited sixteen badminton athletes.The capture frequency of the Vicon Motion System (300Hz), Kistler force platform (1500Hz) and Vicon Nexus Version 1.8.5 software were used simultaneously to capture the kinematic and kinetic parameter of backhand side lateral jump smash footwork. The swing actions were divided into two situations, shadow (footwork and racket swinging practice without targets) and hitting (footwork and stroke shuttlecock) actions, whereas the directions were divided into directional and non-directional. Two-way repeated measures ANOVA with the LSD correction was used to compare the differences among the four conditions. The significance level was set to a = 0.05. Results shown that, at the peak of torque, the ankle plantar flexion of the non-directional shadow (p < 0.05) were greater than that of directional shadow (p < 0.05); meantime, ankle torque change of non-directional shadow (p < 0.05) and directional hitting (p < 0.05) was lower than that of non-directional hitting, but the non-directional hitting was larger compared to non-directional shadow (p < 0.05) at the maximum vertical GRF. The hip extension at peak of torque of directional hitting were larger than that of non-directional shadow (p < 0.05). The shadow actions hip flexion angle was larger than that of directional hitting at initial contact, but the non-directional hitting hip abduction was has the significant difference among all the conditioning. The hip flexion angle of non-directional shadow was larger than that of directional hitting (p < 0.05), the hip abduction angle of the non-directional hitting was greater than that of non-directional shadow (p < 0.05) at the peak VGRF. Elite badminton players execute different training movements; the joint stiffness was in the same state. In the hitting actions has greater ankle and hip joint torque than shadow actions. The badminton player was change joint range of motion to adjust lower limbs stiffness.
Assuntos
Extremidade Inferior/fisiologia , Destreza Motora/fisiologia , Esportes com Raquete/fisiologia , Articulação do Tornozelo/fisiologia , Desempenho Atlético/fisiologia , Fenômenos Biomecânicos , Articulação do Quadril/fisiologia , Humanos , Masculino , Amplitude de Movimento Articular , Estudos de Tempo e Movimento , Torque , Adulto JovemRESUMO
BACKGROUND/OBJECTIVE: The application of Micro-Electro-Mechanical Sensors (MEMS) as measurements of energy expenditure (EE) has certain disadvantages. For example, the inertial sensors cannot easily distinguish changes in ground slope during walking/running conditions, so the accuracy of EE calculation is biased. To resolve this issue, heart rate (HR) and heart rate reserve (HRR) were used as compensatory factors respectively to correct the classical empirical formula of the accelerometer analyzer for EE in this study. METHODS: To explore the improvement of the accuracy of EE during uphill exercise and compare the correction levels between HR and HRR, oxygen uptake was used as a criterion measure (CM). Thirty healthy adult males wore an ActiGraph GT3X with the Polar HR monitor and Vmax indirect calorimeter during twelve treadmill activities (3 gradients and 4 speeds). RESULTS: When the slopes were increased by 0%, 3%, and 6%, the measurement accuracy of the accelerometers, calculated by intraclass correlation coefficient (ICC), decreased by 0.877, 0.755, and 0.504, respectively (pâ¯<â¯0.05). The HR and HRR parameters of linear regression were used to correct the classical formula. The results showed that HR had higher coefficients of determination (R2) (0.801, 0.700, and 0.642 respectively) and ICCs (0.887, 0.825, and 0.785 respectively) than did the accelerometer outputs. HRR showed the highest coefficients of determination (R2) (0.821, 0.728, and 0.656 respectively) and ICCs (0.901, 0.844, and 0.795 respectively). CONCLUSIONS: Through adding HRR parameters, the accuracy of the classical prediction formula EE was significantly improved during walking/running on sloping ground.
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The innate immune response to P. aeruginosa pulmonary infections relies on a network of pattern recognition receptors, including intracellular inflammasome complexes, which can recognize both pathogen- and host-derived signals and subsequently promote downstream inflammatory signaling. Current evidence suggests that the inflammasome does not contribute to bacterial clearance and, in fact, that dysregulated inflammasome activation is harmful in acute and chronic P. aeruginosa lung infection. Given the role of mitochondrial damage signals in recruiting inflammasome signaling, we investigated whether mitochondrial-targeted therapies could attenuate inflammasome signaling in response to P. aeruginosa and decrease pathogenicity of infection. In particular, we investigated the small molecule, ZLN005, which transcriptionally activates peroxisome proliferator-activated receptor-γ coactivator-1α (PGC-1α), a master regulator of mitochondrial biogenesis, antioxidant defense, and cellular respiration. We demonstrate that P. aeruginosa infection promotes the expression of inflammasome components and attenuates several components of mitochondrial repair pathways in vitro in lung epithelial cells and in vivo in an acute pneumonia model. ZLN005 activates PGC-1α and its downstream effector, Sirtuin 3 (SIRT3), a mitochondrial-localized deacetylase important for cellular metabolic processes and for reactive oxygen species homeostasis. ZLN005 also attenuates inflammasome signaling induced by P. aeruginosa in bronchial epithelial cells and this action is dependent on ZLN005 activation of SIRT3. ZLN005 treatment reduces epithelial-barrier dysfunction caused by P. aeruginosa and decreases pathogenicity in an in vivo pneumonia model. Therapies that activate the PGC-1α-SIRT3 axis may provide a complementary approach in the treatment of P. aeruginosa infection.
RESUMO
BACKGROUND: Tea plants are always cultivated in acid soils in hilly regions and their growth can be dependent on to soluble aluminium (Al). The mechanism of Al detoxification and the influence of Al on phenolic compounds (i.e. catechin) in the roots of tea plants has remained obscure. This study aimed to investigate the influence of Al changes on the concentrations of phenolic substances in tea plants through hydroponic experiments. RESULTS: Tea plants were cultivated in nutrient solution containing 1.5 and 2.5 mmol L(-1) Al, and these treatments enhanced the growth of new buds and roots. Aluminium stimulated the uptake of Ca, Mg, K and Mn, whereas the uptake of Fe, Cu and Zn was retarded. Moreover, total phenol concentrations in tea plant tissues increased with increasing Al concentrations. In general, catechin concentrations in leaves increased with increasing Al concentrations in the hydroponic experiments. High correlation coefficients were obtained between Al and (-)-ECG (r(2) = 0.85, P < 0.01) and between Al and total phenols (r(2) = 0.92, P < 0.01). CONCLUSIONS: The Al concentration in tea plants indeed increases catechin concentrations and plays an important role in the growth of tea plants.
Assuntos
Alumínio/metabolismo , Camellia sinensis/crescimento & desenvolvimento , Camellia sinensis/metabolismo , Flavonoides/metabolismo , Hidroponia/métodos , Fenóis/metabolismo , Oligoelementos/metabolismo , Alumínio/administração & dosagem , Transporte Biológico , Catequina/análogos & derivados , Catequina/metabolismo , Concentração Osmolar , Folhas de Planta/crescimento & desenvolvimento , Folhas de Planta/metabolismo , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/metabolismo , PolifenóisRESUMO
Whole body vibration (WBV) has been suggested to improve athletes' neuromuscular strength and power. This study investigated the effect of single WBV stimulation on volleyball-specific performance. The participants were 20 elite male volleyball players who performed a 1-min warm-up exercise on a vibration platform at a frequency of 30 Hz and peak-to-peak displacement of 2 mm. After the warm-up exercise, the participants performed a blocking agility test (BAT), 10-m sprinting test, agility T-test, and counter movement jump test. We compared the participants' performance at four time points (Pretest, Post 0, Post 1, and Post 2). The results revealed that the participants' BAT performance and maximum rate of force development improved significantly 1 min after the vibration stimulation (p < 0.01). The WBV (frequency of 30-Hz, peak-to-peak displacement of 2 mm) intervention significantly improved the volleyball-specific defensive performance and speed strength of the participants. Accordingly, by undergoing WBV as a form of warm-up exercise, the technique and physical fitness of volleyball players can be improved.
Assuntos
Desempenho Atlético , Força Muscular , Aptidão Física , Vibração , Voleibol , Exercício de Aquecimento , Adulto , Humanos , MasculinoRESUMO
Previous research in badminton has associated unilateral landings following overhead strokes with the occurrence of knee injuries. Smashing involves tensing the abdomen muscles while swinging the racket rapidly and maintaining one's balance while performing coordinated movements and steps; this process puts stress on the player's lower limbs. However, few studies have compared the effects of different stroke training while performing various types of badminton strokes. This study investigated the influence of different stroke training on the smash action of badminton players. Three stroke training conditions were considered: shadow, target striking, and smashing. Sixteen male experienced badminton players were recruited for this study. One-way repeated-measures ANOVA with Bonferroni correction was used to identify the differences. At the initial contact with the ground, the knee flexion and knee valgus angles under the smash condition were significantly higher than target and shadow conditions. Under the smash condition, hip abduction was significantly higher than under the target and shadow conditions. Moreover, the hip abduction under the target condition was significantly higher than under the shadow condition. At the maximum knee flexion, the hip abduction under the smash and target conditions was significantly higher than under the shadow condition. Regarding the time from the moment of initial contact to the peak of vertical ground reaction force it was shorter under the smash condition than the target and shadow conditions. The vertical ground reaction force was higher under the smash condition than under the target and shadow conditions. The 50 ms impulse was higher under the smash condition than under the target and shadow conditions. The main findings of this study are that under the smash condition, the motion in the frontal plane increased, which produced higher loads on the joints in the lower limbs. Player performed the same footwork under the three conditions, but the landing strategies differed because of unique swing motions and techniques. The condition under which a player hits a shot to a target area can affect the landing. The results of this study suggest that target practice is more effective for improving the landing technique employed during actual shots than shadow practice.
RESUMO
The purpose of this research was to study the effects of a whole-body vibration (WBV) warm-up for improving fencers' performance on variables derived from a lunge reaction test, the 10-meter sprint, and the countermovement jump. We compared fencer performances at four time intervals: (a) preintervention, (b) immediately postintervention, (c) 1-minute postintervention, and (d) 2-minute postintervention. Study participants were 16 male fencers. The vibration frequency was 30 Hz, and its amplitude was two mm. After each WBV session, participants significantly improved their performance on all measures at both one and two minutes after the intervention. Specifically, lunge reaction tests scores improved by 5.50% and 7.34%, respectively, relative to preintevention testing (p < .01), peak power output improved by 4.94% and 11.52%, respectively (p < .05), and maximum rate of force development improved by 13.41% and 18.38%, respectively (p < .01). Acute WBV (frequency = 30 Hz, peak-to-peak amplitude of two mm) induced neuromuscular activation and improved lunge reaction scores, agility, and power.
Assuntos
Desempenho Atlético , Vibração/uso terapêutico , Exercício de Aquecimento , Adolescente , Humanos , Masculino , Força Muscular , Adulto JovemRESUMO
BACKGROUND: Using wearable inertial sensors to accurately estimate energy expenditure (EE) during an athletic training process is important. Due to the characteristics of inertial sensors, however, the positions in which they are worn can produce signals of different natures. To understand and solve this issue, this study used the heart rate reserve (HRR) as a compensation factor to modify the traditional empirical equation of the accelerometer EE sensor and examine the possibility of improving the estimation of energy expenditure for sensors worn in different positions. METHODS: Indirect calorimetry was used as the criterion measure (CM) to measure the EE of 90 healthy adults on a treadmill (five speeds: 4.8, 6.4, 8.0, 9.7, and 11.3 km/h). The measurement was simultaneously performed with the ActiGraph GT9X-Link (placed on the wrist and waist) with the Polar H10 Heart Rate Monitor. RESULTS: At the same exercise intensity, the EE measurements of the GT9X on the wrist and waist had significant differences from those of the CM (p < 0.05). By using multiple regression analysis-utilizing values from vector magnitudes (VM), body weight (BW) and HRR parameters-accuracy of EE estimation was greatly improved compared to traditional equation. Modified models explained a greater proportion of variance (R2) (wrist: 0.802; waist: 0.805) and demonstrated a good ICC (wrist: 0.863, waist: 0.889) compared to Freedson's VM3 Combination equation (R2: wrist: 0.384, waist: 0.783; ICC: wrist: 0.073, waist: 0.868). CONCLUSIONS: The EE estimation equation combining the VM of accelerometer measurements, BW and HRR greatly enhanced the accuracy of EE estimation based on data from accelerometers worn in different positions, particularly from those on the wrist.
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The aims of this study were to make use of organo-clays (i.e., Cloisite-10A, Cloisite-15A, Cloisite-30B and Cloisite-93A), to remove p-nitrophenol, phenol and aniline of organic pollutants. The organo-clays were characterized by X-ray diffraction (XRD). Sorption isotherm, kinetic and pH effect of p-nitrophenol, phenol and aniline sorbed by four organo-clays were evaluated. The d-spacings (001) of the XRD peak of Cloisite-10A, Cloisite-15A, Cloisite-30B and Cloisite-93A are 1.98, 2.76, 1.93 and 2.64 nm, respectively. The d(001)-spacings of XRD indicated that these p-nitropheno, phenol and aniline could penetrate into the interlayer of clays and expand the d(001)-spacings. The linear sorption isotherm of constant partition was employed to describe the sorption isotherms of phenols sorbed by organo-clays through hydrophobic-hydrophobic chemical reactions. The parabolic diffusion and power-function of kinetic models were employed to describe properly the kinetic experiments. The rate limiting step of the p-nitrophenol sorption reactions on organo-clays were diffusion-controlled processes (i.e., 15A, 30B, 93A) and chemical-controlled process for 10A organo-clays. The pre-exponential factor of the p-nitrophenol sorbed by four organo-clays showed the trend as follows: 10A> 30B> 93A> 15A. The efficiency of these organo-clays in removing phenol compounds in water treatments merit further study.
Assuntos
Silicatos de Alumínio/química , Compostos de Anilina/química , Nitrocompostos/química , Fenóis/química , Adsorção , Alquilação , Argila , Concentração de Íons de Hidrogênio , Cinética , Estrutura Molecular , Compostos de Amônio Quaternário/química , Temperatura , Difração de Raios XRESUMO
Due to their destructive and sporadic nature, it is often difficult to evaluate and predict the effects of typhoon on forest ecosystem patterns and processes. We used a 21-yr record of litterfall rates to explore the influence of typhoon frequency and intensity, along with other meteorological variables, on ecosystem dynamics in a subtropical rainforest. Over the past half century there has been an increasing frequency of strong typhoons (category 3; >49.6 m s-1; increase of 1.5 typhoons/decade) impacting the Fushan Experimental Forest, Taiwan. At Fushan strong typhoons drive total litterfall mass with an average of 1100 kg ha-1 litterfall typhoon-1. While mean typhoon season litterfall has been observed to vary by an order of magnitude, mean litterfall rates associated with annual leaf senescence vary by <20%. In response to increasing typhoon frequency, total annual litter mass increased gradually over the 21-year record following three major typhoons in 1994. Monthly maximum wind speed was predictive of monthly litterfall, yet the influence of precipitation and temperature was only evident in non-typhoon affected months. The response of this subtropical forest to strong typhoons suggests that increasing typhoon frequency has already shifted ecosystem structure and function (declining carbon sequestration and forest stature).
Assuntos
Mudança Climática/estatística & dados numéricos , Tempestades Ciclônicas/estatística & dados numéricos , Florestas , Árvores/fisiologia , Chuva , Taiwan , Temperatura , Árvores/classificação , Clima TropicalRESUMO
This study investigates the species of As and Pb (beudantite) residues present in the seriously contaminated agricultural rice soils of the Guandu Plain. Two pedons in the Guandu Plain agricultural soils, each pedon separated into five horizons (each of 20 cm) were collected for this study. Soil samples were packed into a column for leaching with simulated acid rains. Soil pH ranged from 5.1 to 7.1 with high base saturation. Soils can be classified as clay loam, mixed, thermic, Typic or Umbric Albaqualfs. The XRD analysis indicated the beudantite particles are present in clay fractions, showing high concentrations of As and Pb. This is because of 50-100 years ago irrigation water was introduced from Huang Gang Creek of hot springs containing high concentrations of As and Pb. Only low concentrations of As and Pb can be leached out with simulated acid rains (i.e., pHs 2 and 4), even through 40 pore volumes of leaching experiments. The sequential extraction experiments resulted in the high portions of As and Pb remaining in the amorphous, Fe and Al oxyhydroxides and residual fractions. Thus, the remediation of As and Pb in this agricultural rice paddy soils merits further study.