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OBJECTIVE: The study aimed to pool and analyze the effects of different forms of exercise on muscle strength (handgrip strength [HGS]), and physical performance (timed up and go test [TUGT], gait speed [GS] and chair stand test [CS]) in older adults with sarcopenia. METHODS: The effect sizes of all studies retrieved and included by the four databases were analyzed using the network meta-analysis and expressed as standardized mean differences (SMD) and the corresponding 95% confidence intervals (CI). RESULTS: Twenty studies were included in this study with 1347 older adults with sarcopenia. Compared with control and other intervention groups, resistance training (RT) improved HGS [SMD=3.8, 95% CI (1.3, 6.0), p<0.05] and TUGT [SMD = -1.99, 95% CI (-2.82, -1.16), p<0.05] significantly. comprehensive training (CT) [SMD = -2.04, 95% CI (-3.05, -1.06), Pp<0.05] and Comprehensive training under self-management (CT_SM) [SMD = -2.01, 95% CI (-3.24, -0.78), p<0.05] improved TUGT significantly. CONCLUSION: In older adults with sarcopenia, RT could improve HGS and TUGT, CT and CT_SM could improve TUGT. There were no significant changes in CS and GS with any of the exercise training modes.
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Sarcopenia , Humanos , Idoso , Sarcopenia/terapia , Força da Mão/fisiologia , Metanálise em Rede , Equilíbrio Postural , Estudos de Tempo e Movimento , Força Muscular/fisiologia , Exercício Físico/fisiologiaRESUMO
This case-control study aimed to analysis of the relationship between individual behaviours and sports risk factors and injuries among skiers and snowboarders. During the 2021-2022 winter season, 1132 injured and 1069 non-injured skiers and snowboarders were surveyed regarding demographic, self-reported individual behavioural and sporting characteristics. Multivariate regression analysis revealed previous snow-sports injury (OR: 26.39, 95% CI: 13.32-52.31, P < 0.001), nervousness (OR: 3.78, 95% CI: 2.91-4.90, P < 0.001), calm (OR: 1.90, 95% CI: 1.46-2.48, P < 0.001) and fearful (OR: 20.60, 95% CI: 11.45-37.04, P < 0.001) emotional states, and higher risk-taking behaviours (OR: 3.72, 95% CI: 2.87-4.83, P < 0.001) were important risk factors associated with injuries to all skiers and snowboarders. Compared to snowboarders, the risk of injury to skiers was more likely to increase as the length of their skiing experience increases. Emotional and cognitive levels appear to be important conditions that influence injuries to skiers and snowboarders, a proper understanding of the potential interactions between cognition and behaviour appears to be important for public ski safety management.
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Bacterial symbionts associated with insects are often involved in host development and ecological adaptation. Serratia symbiotica, a common facultative endosymbiont harbored in pea aphids, improves host fitness and heat tolerance, but studies concerning the nutritional metabolism and impact on the aphid host associated with carrying Serratia are limited. In the current study, we showed that Serratia-infected aphids had a shorter nymphal developmental time and higher body weight than Serratia-free aphids when fed on detached leaves. Genes connecting to fatty acid biosynthesis and elongation were up-regulated in Serratia-infected aphids. Specifically, elevated expression of fatty acid synthase 1 (FASN1) and diacylglycerol-o-acyltransferase 2 (DGAT2) could result in accumulation of myristic acid, palmitic acid, linoleic acid, and arachidic acid in fat bodies. Impairing fatty acid synthesis in Serratia-infected pea aphids either by a pharmacological inhibitor or through silencing FASN1 and DGAT2 expression prolonged the nymphal growth period and decreased the aphid body weight. Conversely, supplementation of myristic acid (C14:0) to these aphids restored their normal development and weight gain. Our results indicated that Serratia promoted development and growth of its aphid host through enhancing fatty acid biosynthesis. Our discovery has shed more light on nutritional effects underlying the symbiosis between aphids and facultative endosymbionts.
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Afídeos , Ácidos Graxos/metabolismo , Interações entre Hospedeiro e Microrganismos , Serratia/fisiologia , Simbiose , Animais , Afídeos/metabolismo , Afídeos/microbiologiaRESUMO
Aphids often carry facultative symbionts to achieve diverse advantages. Serratia symbiotica, one of facultative endosymbionts, increases aphid tolerance to heat. However, whether it benefits aphid colonization on host plants is yet to be determined. In the current study, we found that Acyrthosiphon pisum harbouring S. symbiotica had longer feeding duration on Medicago truncatula than Serratia-free aphids. Contrastingly, Serratia-free aphids triggered higher accumulation of reactive oxygen species (ROS), jasmonic acid and salicylic acid responsive genes and cytosolic Ca2+ elevations than Serratia-infected aphids. Transcriptomic analysis of salivary glands indicated that a histidine-rich Ca2+ -binding protein-like gene (ApHRC) was expressed more highly in the salivary gland of Serratia-infected aphids than that of Serratia-free aphids. Once ApHRC was silenced, Serratia-infected aphids also displayed shorter phloem-feeding duration and caused Ca2+ elevation and ROS accumulation in plants. Our results suggest that ApHRC, a potential effector up-regulated by S. symbiotica in the salivary glands, impairs plant defence response by suppressing Ca2+ elevation and ROS accumulation, allowing colonization of aphids. This study has provided an insight into how facultative symbionts facilitate aphid colonization and adaptation to host plants.
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Afídeos/fisiologia , Medicago truncatula/fisiologia , Glândulas Salivares/fisiologia , Serratia/fisiologia , Animais , Afídeos/genética , Afídeos/microbiologia , Cálcio/metabolismo , China , Expressão Gênica , Proteínas de Insetos/genética , Plantas Geneticamente Modificadas , Espécies Reativas de Oxigênio/metabolismo , SimbioseRESUMO
Small RNAs play an important role in plant immune responses. However, their regulatory function in induced systemic resistance (ISR) is nascent. Bacillus cereus AR156 is a plant growth-promoting rhizobacterium that induces ISR in Arabidopsis against bacterial infection. Here, by comparing small RNA profiles of Pseudomonas syringae pv. tomato (Pst) DC3000-infected Arabidopsis with and without AR156 pretreatment, we identified a group of Arabidopsis microRNAs (miRNAs) that are differentially regulated by AR156 pretreatment. miR825 and miR825* are two miRNA generated from a single miRNA gene. Northern blot analysis indicated that they were significantly downregulated in Pst DC3000-infected plants pretreated with AR156, in contrast to the plants without AR156 pretreatment. miR825 targets two ubiquitin-protein ligases, while miR825* targets toll-interleukin-like receptor (TIR)-nucleotide binding site (NBS) and leucine-rich repeat (LRR) type resistance (R) genes. The expression of these target genes negatively correlated with the expression of miR825 and miR825*. Moreover, transgenic plants showing reduced expression of miR825 and miR825* displayed enhanced resistance to Pst DC3000 infection, whereas transgenic plants overexpressing miR825 and miR825* were more susceptible. Taken together, our data indicates that Bacillus cereus AR156 pretreatment primes ISR to Pst infection by suppressing miR825 and miR825* and activating the defense related genes they targeted.
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Arabidopsis/genética , Arabidopsis/microbiologia , Bacillus cereus/fisiologia , Resistência à Doença/genética , MicroRNAs/genética , Doenças das Plantas/genética , Doenças das Plantas/microbiologia , Arabidopsis/imunologia , Sequência de Bases , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Técnicas de Silenciamento de Genes , Genes de Plantas , Loci Gênicos , MicroRNAs/metabolismo , Plantas Geneticamente Modificadas , Pseudomonas syringae/fisiologia , RNA Interferente Pequeno/metabolismoRESUMO
The main purpose of this cross-sectional study was to examine the impact of the inter-limb asymmetry of hamstring strength on jump, sprint and strength performance and to compare the effects of inter-limb asymmetry of hamstring strength with gross force (GF) of the hamstring on these physical qualities in youth volleyball athletes. Eighty-one youth volleyball players (age: 16.6 ± 1.9 years; training experience: 3.0 ± 0.9 years; height: 191.4 ± 7.1 cm; body mass: 78.5 ± 12.9 kg; lean body mass: 63.5 ± 10.5 kg; body fat rate: 18.6% ± 6.1%) performed a mid-season battery of tests consisting of morphological test, depth jump (DJ), counter movement jump (CMJ), squat jump (SJ), 10 m sprint, isometric mid-thigh pull (IMTP) and hamstring strength test. All tests reported good to excellent reliability (ICC range = 0.815-0.996) and acceptable variability (CV range = 3.26-7.84%). Results show a significant negative relationship between inter-limb asymmetry of hamstring strength and all physical qualities (r = -0.271 to -0.445; p < 0.05), and a significant positive relationship between GF of hamstring and all physical qualities (r = 0.303 to 0.664; p < 0.05). Additionally, GF of hamstring was more relevant to IMTP-PF (peak force) (r = 0.664) and inter-limb asymmetry of hamstring strength was more relevant to 10 m sprint (r = -0.445). The findings from this study indicate that, for youth athletes, the GF of the hamstring is crucial for overall lower limb strength performance, and the importance of inter-limb symmetry of hamstring strength increases with the complexity of the task.
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BACKGROUND: Plants have evolved sophisticated defense responses to insect herbivore attack, which often involve elicitors in the insects' oral secretions. The major eliciting compounds in insect oral secretions across different species and their potency in inducing volatile emissions have not yet been fully characterized and compared. RESULTS: Seven lepidopteran insects with variable duration of association with maize were selected, five species known as pests for a long time (Ostrinia furnacalis, Spodoptera exigua, Spodoptera litura, Mythimna separata, and Helicoverpa armigera) and two newly emerging pests (Athetis lepigone and Athetis dissimilis). Oral secretions of the newly emerging pests have the highest total contents of Fatty Acid-Amino Acid Conjugates (FACs), and their relative composition was well separated from that of the other five species in principal compound analysis. Redundancy analyses suggested that higher quantity of FACs was mainly responsible for the increases in maize volatiles, of which (E)-3,8-dimethyl-1,4,7-nonatriene (DMNT) and (E, E)-4,8,12-trimethyltrideca-1,3,7,11-tetraene (TMTT) were the most strongly inducible compounds. Adding FACs to the oral secretion of S. litura larvae significantly increased the emissions of TMTT and DMNT, confirming the key role of FACs in inducing volatile emissions in maize plants. Additional experiments with artificial diet spiked with linolenic acid suggested that variation in FACs is due to differences in internal FAC degradation and fatty acid excretion. CONCLUSION: Compared with two newly emerging pests A. lepigone and A. dissimilis, the long-term pests could diminish the volatile emission by maize through reducing the FAC content in their oral secretions, which may lower the risk of attracting natural enemies.
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Aminoácidos , Ácidos Graxos , Animais , Herbivoria , Larva , SpodopteraRESUMO
Chemerin and its receptor CMKLR1 (a G-protein-coupled receptor) are inducers of inflammation, and play an important role in diabetic cardiomyopathy (DCM). In this study, we investigated the role of the chemerin/CMKLR1 axis in mediating inflammation and cell death in DCM. Sprague-Dawley rats, treated with a high-fat diet and low-dose of streptozotocin, were used as a DCM model. CMKLR1 expression was knocked down by siRNA (CMKLR1-siRNA) to evaluate the role of CMKLR1 in DCM. Chemerin-treated H9c2 cells were used to investigate the factors acting downstream of the chemerin/CMKLR1 axis. LDH release and EthD-III staining were used to measure the ratio of cell death in vitro. CMKLR1-siRNA and siRNA against nucleotide-binding oligomerization domain-like receptors 3 (NLRP3-siRNA) were used to explore the mechanism underlying chemerin-induced inflammation and cell death. The results showed that the expression of chemerin, CMKLR1, NLRP3, pro-caspase-1, activated caspase-1, and mature IL-1ß was increased in the DCM model rat. Myocardium of DCM model rats exhibited fibrosis, hypertrophy, a disorganized ultrastructure, and impaired function. Pyroptosis was observed in vivo and in vitro. Silencing of CMKLR1 in vivo attenuated the expression of NLRP3 and activated caspase-1 and IL-1ß. CMKLR1-siRNA treatment attenuated cardiac inflammation, fibrosis, hypertrophy, and pyroptosis, and improved cardiac function in vivo. Silencing of either CMKLR1 or NLRP3 suppressed the levels of activated caspase-1, IL-1ß, and pyroptosis; however, silencing of both CMKLR1 and NLRP3 further decreased the levels of mature IL-1ß and pyroptosis. Overall, the results showed that the chemerin/CMKLR1 axis contributed to the development of DCM and that the NLRP3 inflammasome mediated the chemerin/CMLR1-induced inflammation and pyroptosis. These data indicate that silencing of the CMKLR1 gene might exert a protective effect against DCM.
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Spinel oxide NiCo2O4 supported on a three-dimensional hierarchically porous graphene-like carbon (3D HPG) material has been firstly used to enhance the activity of Pt for glycerol electrooxidation. The addition of NiCo2O4 into the Pt/HPG catalyst can significantly improve the catalytic performance for glycerol oxidation. When NiCo2O4 is added to the Pt/HPG catalyst, the onset potential is 25 mV more negative than that on the Pt/HPG catalyst without NiCo2O4. The current density at -0.3 V on the Pt-NiCo2O4 (wt 10 : 1)/HPG electrode is 1.3 times higher than that on the Pt (30 wt%)/HPG electrode. The Pt-NiCo2O4 electrode presented in this work shows great potential as an electrocatalyst for glycerol electrooxidation in an alkaline medium.
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As an usually occurs in athletes, iliotibial band syndrome is payed more attention for people, the disease is diagnosed mainly by clinical symptoms, physical examination and MRI, but there is no uniform diagnostic criteria. The pathogenesis of iliotibial band syndrome is considered to be related to pressure and friction factors. As for the treatment, manipulation, muscle exercise, mainly drugs and physical therapy and so on both at home and abroad are recognized to use to achieve desired effect. For conservative failure, refractory iliotibial band syndrome patients, arthroscopy, or release of iliotibial band syndrome surgery are performed. While conservative local drug injection combined with muscle exercise could play a role in pain management besides, arthroscopic as operation method is more advanced, and applicable to all types of patients without absolute contraindication, so it is helpful for patients with early activity. At present, there is still a great deal of controversy about its pathogenesis, and there is no obvious limit for the specific indications of its various therapies in clinic, so it needs further specification.