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1.
Psychol Sport Exerc ; 64: 102341, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-37665822

RESUMEN

OBJECTIVES: Athlete burnout is a maladaptive outcome that is potentially detrimental for performance and wellbeing. Cross-sectional evidence suggests that mindfulness might be associated with athlete burnout via experiential avoidance and cognitive fusion. In the current study, we extend knowledge of these hypothesized mediational pathways using a longitudinal design. METHODS: Data was collected at three occasions with a three-month interval. A final sample of 280 elite Chinese athletes aged 15-32 years (Mage = 19.13; SD = 2.92; Female = 130) reported their mindfulness at Time 1, experiential avoidance and cognitive fusion at Time 2, and athlete burnout at Time 3. Structural equation modelling was adopted to examine the mediating roles of experiential avoidance and cognitive fusion on the effects from mindfulness to athlete burnout. RESULTS: We found statistically meaningful directs effects from mindfulness (Time 1) to experiential avoidance and cognitive fusion (Time 2), which in turn influenced athlete burnout (Time 3). However, the direct effect from mindfulness at Time 1 to athlete burnout at Time 3 was non-significant. The indirect effects of experiential avoidance and cognitive fusion on the effects from mindfulness to athlete burnout were significant, providing longitudinal evidence that these two variables contribute meaningfully to the mindfulness-burnout pathway. CONCLUSION: With initial evidence for the mediating effects of experiential avoidance and cognitive fusion, future studies could consider using experimental designs to examine the potential changing mechanisms of mindfulness on reducing athlete burnout.


Asunto(s)
Atención Plena , Femenino , Humanos , Estudios Longitudinales , Estudios Transversales , Agotamiento Psicológico , Atletas , Cognición
2.
Microbiome ; 10(1): 101, 2022 07 04.
Artículo en Inglés | MEDLINE | ID: mdl-35787295

RESUMEN

BACKGROUND: Phosphorus (P) is one of the most essential macronutrients on the planet, and microorganisms (including bacteria and archaea) play a key role in P cycling in all living things and ecosystems. However, our comprehensive understanding of key P cycling genes (PCGs) and microorganisms (PCMs) as well as their ecological functions remains elusive even with the rapid advancement of metagenome sequencing technologies. One of major challenges is a lack of a comprehensive and accurately annotated P cycling functional gene database. RESULTS: In this study, we constructed a well-curated P cycling database (PCycDB) covering 139 gene families and 10 P metabolic processes, including several previously ignored PCGs such as pafA encoding phosphate-insensitive phosphatase, ptxABCD (phosphite-related genes), and novel aepXVWPS genes for 2-aminoethylphosphonate transporters. We achieved an annotation accuracy, positive predictive value (PPV), sensitivity, specificity, and negative predictive value (NPV) of 99.8%, 96.1%, 99.9%, 99.8%, and 99.9%, respectively, for simulated gene datasets. Compared to other orthology databases, PCycDB is more accurate, more comprehensive, and faster to profile the PCGs. We used PCycDB to analyze P cycling microbial communities from representative natural and engineered environments and showed that PCycDB could apply to different environments. CONCLUSIONS: We demonstrate that PCycDB is a powerful tool for advancing our understanding of microbially driven P cycling in the environment with high coverage, high accuracy, and rapid analysis of metagenome sequencing data. The PCycDB is available at https://github.com/ZengJiaxiong/Phosphorus-cycling-database . Video Abstract.


Asunto(s)
Microbiota , Fósforo , Bacterias/genética , Bases de Datos Factuales , Metagenoma/genética
3.
Microbiome ; 8(1): 32, 2020 03 10.
Artículo en Inglés | MEDLINE | ID: mdl-32156316

RESUMEN

BACKGROUND: Recently, increasing evidence supports that some complex diseases are not attributed to a given pathogen, but dysbiosis in the host intestinal microbiota (IM). The full intestinal ecosystem alterations, rather than a single pathogen, are associated with white feces syndrome (WFS), a globally severe non-infectious shrimp disease, while no experimental evidence to explore the causality. Herein, we conducted comprehensive metagenomic and metabolomic analysis, and intestinal microbiota transplantation (IMT) to investigate the causal relationship between IM dysbiosis and WFS. RESULTS: Compared to the Control shrimp, we found dramatically decreased microbial richness and diversity in WFS shrimp. Ten genera, such as Vibrio, Candidatus Bacilloplasma, Photobacterium, and Aeromonas, were overrepresented in WFS, whereas 11 genera, including Shewanella, Chitinibacter, and Rhodobacter were enriched in control. The divergent changes in these populations might contribute the observation that a decline of pathways conferring lipoic acid metabolism and mineral absorption in WFS. Meanwhile, some sorts of metabolites, especially lipids and organic acids, were found to be related to the IM alteration in WFS. Integrated with multiomics and IMT, we demonstrated that significant alterations in the community composition, functional potentials, and metabolites of IM were closely linked to shrimp WFS. The distinguished metabolites which were attributed to the IM dysbiosis were validated by feed-supplementary challenge. Both homogenous selection and heterogeneous selection process were less pronounced in WFS microbial community assembly. Notably, IMT shrimp from WFS donors eventually developed WFS clinical signs, while the dysbiotic IM can be recharacterized in recipient shrimp. CONCLUSIONS: Collectively, our findings offer solid evidence of the causality between IM dysbiosis and shrimp WFS, which exemplify the 'microecological Koch's postulates' (an intestinal microbiota dysbiosis, a disease) in disease etiology, and inspire our cogitation on etiology from an ecological perspective. Video abstract.


Asunto(s)
Disbiosis/microbiología , Trasplante de Microbiota Fecal/veterinaria , Microbioma Gastrointestinal , Intestinos/microbiología , Penaeidae/microbiología , Animales , Bacterias/clasificación , Bacterias/aislamiento & purificación , Heces/microbiología , Variación Genética , Intestinos/fisiopatología
4.
Cell Death Dis ; 10(10): 742, 2019 10 03.
Artículo en Inglés | MEDLINE | ID: mdl-31582735

RESUMEN

Pigment epithelium-derived factor (PEDF), a classic angiogenic inhibitor, has been reported to function as a tumor suppression protein and to downregulate in many types of solid tumors. However, the expression level of PEDF and its role in hepatocellular carcinoma (HCC) are contradictory. The present study investigates the expression and different activities of secreted and intracellular PEDF during HCC development, as well as the underlying mechanism of PEDF on HCC lipid disorders. We found that PEDF had no association with patients' prognosis, although PEDF was highly expressed and inhibited angiogenesis in HCC tumor tissues. The animal experiments indicated that full-length PEDF exhibited equalizing effects on tumor growth activation and tumor angiogenesis inhibition in the late stage of HCC progression. Importantly, the pro-tumor activity was mediated by the intracellular PEDF, which causes accumulation of free fatty acids (FFAs) in vivo and in vitro. Based on the correlation analysis of PEDF and lipid metabolic indexes in human HCC tissues, we demonstrated that the intracellular PEDF led to the accumulation of FFA and eventually promoted HCC cell growth by inhibiting the activation of AMPK via ubiquitin-proteasome-mediated degradation, which causes increased de novo fatty acid synthesis and decreased FFA oxidation. Our findings revealed why elevated PEDF did not improve the patients' prognosis as the offsetting intracellular and extracellular activities. This study will lead to a comprehensive understanding of the diverse role of PEDF in HCC and provide a new selective strategy by supplement of extracellular PEDF and downregulation of intracellular PEDF for the prevention and treatment of liver cancer.


Asunto(s)
Carcinoma Hepatocelular/metabolismo , Espacio Extracelular/metabolismo , Proteínas del Ojo/metabolismo , Espacio Intracelular/metabolismo , Neoplasias Hepáticas/metabolismo , Factores de Crecimiento Nervioso/metabolismo , Serpinas/metabolismo , Adenilato Quinasa/metabolismo , Adulto , Anciano , Anciano de 80 o más Años , Animales , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patología , Línea Celular Tumoral , Proliferación Celular/genética , Proteínas del Ojo/genética , Ácidos Grasos/metabolismo , Femenino , Regulación Neoplásica de la Expresión Génica , Humanos , Metabolismo de los Lípidos/genética , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patología , Masculino , Ratones Endogámicos BALB C , Ratones Desnudos , Persona de Mediana Edad , Modelos Biológicos , Estadificación de Neoplasias , Factores de Crecimiento Nervioso/genética , Pronóstico , Complejo de la Endopetidasa Proteasomal/metabolismo , Proteolisis , Serpinas/genética , Ubiquitina/metabolismo , Ensayos Antitumor por Modelo de Xenoinjerto
5.
Phytomedicine ; 44: 187-203, 2018 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-29526584

RESUMEN

BACKGROUND: Fuzi, which is the processed lateral roots of Aconitum carmichaeli Debx. (Ranunculaceae), is a traditional herbal medicine that is well known for its excellent pharmacological effects and acute toxicity. Aconitum alkaloids are responsible for its pharmacological activity and toxicity. Although a large number of studies on Fuzi have been reported, no comprehensive review on its pharmacokinetics has yet been published. PURPOSE: This paper seeks to present a comprehensive review regarding the phytochemistry, pharmacokinetic features and toxicity of Fuzi. The regulation of drug-metabolizing enzymes (DMEs) and efflux transporters (ETs) by Fuzi is also concluded. Additionally, the use of Fuzi as a personalized medicine based on the bioavailability barrier (BB), which mainly comprises DMEs and ETs, is discussed. METHODS: All available information on Fuzi was collected by searching for key words in PubMed, ScienceDirect, CNKI, Google Scholar, Baidu Scholar, and Web of Science. RESULTS: Aconitum alkaloids, which mainly include diester-diterpene alkaloids (DDAs), monoester-diterpene alkaloids (MDAs) and unesterified-diterpene alkaloids (UDAs), could be detected after Fuzi ingestion in vivo. The Aconitum alkaloids are rapidly absorbed in the intestine and extensively distributed in the body. DMEs, especially CYP3A4/5, are responsible for various types of metabolic reactions of the Aconitum alkaloids. ETs, including P-glycoprotein (P-gp), multidrug resistance-associated protein 2 (MRP2), and breast cancer resistance protein (BCRP), are involved in the efflux of the DDAs and MDAs. The kidney is the most important organ involved in the excretion of the Aconitum alkaloids. DDAs are the main toxic compounds present in Fuzi, and their acute toxicity is mainly due to their effects on the voltage-dependent sodium channels. Furthermore, Fuzi can substantially regulate DMEs and ETs. CONCLUSIONS: The toxicity of DDAs is acute. However, further investigations are necessary to determine the exact toxicological mechanisms. The significant impact of Fuzi on DMEs and ETs suggests that the co-administration of Fuzi with drugs that are substrates of DMEs and/or ETs may cause herb-drug interactions (HDIs). The BB network controlled exposure to the Aconitum alkaloids in vivo. Polymorphisms of DMEs and ETs in different individuals contribute to the differences in the efficacy and toxicity of Fuzi ingestion. In the future, the use of Fuzi as personalized medicine based on the BB network is necessary and practical to achieve ideal therapeutic efficacy with minimal toxicity.


Asunto(s)
Diterpenos/química , Diterpenos/farmacocinética , Aconitum/química , Alcaloides/química , Alcaloides/farmacocinética , Alcaloides/farmacología , Animales , Disponibilidad Biológica , Cromatografía Líquida de Alta Presión , Diterpenos/toxicidad , Medicamentos Herbarios Chinos , Interacciones de Hierba-Droga , Humanos , Inactivación Metabólica/efectos de los fármacos , Fitoterapia/métodos , Extractos Vegetales/química , Medicina de Precisión , Distribución Tisular
6.
Nutrients ; 8(1)2016 Jan 13.
Artículo en Inglés | MEDLINE | ID: mdl-26771636

RESUMEN

Ischemic stroke, characterized by the disturbance of the blood supply to the brain, is a severe worldwide health threat with high mortality and morbidity. However, there is no effective pharmacotherapy for ischemic injury. Currently, combined treatment is highly recommended for this devastating injury. In the present study, we investigated neuroprotective effects of the combination of omega-3 polyunsaturated fatty acids (ω-3 PUFAs) and Lyciumbarbarum polysaccharide (LBP) on cortical neurons using an in vitro ischemic model. Our study demonstrated that treatment with docosahexaenoic acid (DHA), a major component of the ω-3 PUFAs family, significantly inhibited the increase of intracellular Ca(2+) in cultured wild type (WT) cortical neurons subjected to oxygen-glucose deprivation/reperfusion (OGD/R) injury and promoted their survival compared with the vehicle-treated control. The protective effects were further confirmed in cultured neurons with high endogenous ω-3 PUFAs that were isolated from fat-1 mice, in that a higher survival rate was found in fat-1 neurons compared with wild-type neurons after OGD/R injury. Our study also found that treatment with LBP (50 mg/L) activated Trk-B signaling in cortical neurons and significantly attenuated OGD/R-induced cell apoptosis compared with the control. Notably, both combining LBP treatment with ω-3 PUFAs administration to WT neurons and adding LBP to fat-1 neurons showed enhanced effects on protecting cortical neurons against OGD/R injury via concurrently regulating the intracellular calcium overload and neurotrophic pathway. The results of the study suggest that ω-3 PUFAs and LBP are promising candidates for combined pharmacotherapy for ischemic stroke.


Asunto(s)
Ácidos Docosahexaenoicos/farmacología , Medicamentos Herbarios Chinos/farmacología , Neuronas/efectos de los fármacos , Fármacos Neuroprotectores/farmacología , Daño por Reperfusión/tratamiento farmacológico , Animales , Apoptosis/efectos de los fármacos , Cadherinas , Hipoxia de la Célula/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Células Cultivadas , Corteza Cerebral/citología , Ácidos Docosahexaenoicos/administración & dosificación , Quimioterapia Combinada , Medicamentos Herbarios Chinos/administración & dosificación , Glucosa/deficiencia , Proteínas Sensoras del Calcio Intracelular/efectos de los fármacos , Ratones , Ratones Endogámicos C57BL , Neuronas/metabolismo , Fármacos Neuroprotectores/administración & dosificación , Oxígeno/metabolismo , Receptor trkB/efectos de los fármacos , Transducción de Señal/efectos de los fármacos , Accidente Cerebrovascular/tratamiento farmacológico
7.
Fish Shellfish Immunol ; 41(2): 402-6, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25266890

RESUMEN

This study was conducted to evaluate the effects of laminarin on the growth performance, immunological and biochemical parameters, as well as immune related genes expression in the grouper, Epinephelus coioides. One hundred and eight fish were randomly divided into four groups (45 groupers/group). Blank control group was fed with the basal diet, while low, medium and high doses of laminarin groups were fed with the basal diet supplemented with 0.5%, 1.0%, and 1.5% laminarin, respectively, for 48 days. The immunological and biochemical parameters in blood were investigated. The mRNA levels of IL-1ß, IL-8, and TLR2 in midgut were also evaluated by quantitative real-time PCR. Dietary laminarin supplementation significantly improved the specific growth rate and the feed efficiency ratio of the fish. The level of TP and the activity of LZM, CAT and SOD were higher than that of the control. The levels of UREA and CREA as well as the activity of ALP were lower than of the control. There was no significant difference in the levels of ALT and AST between control groups and treated groups. In addition, dietary laminarin supplementation decreased the levels of C3 and C4. The expression of immune response genes IL-1ß, IL-8, and TLR2 showed significant increases (P < 0.05) in groupers fed low dose (0.5%) and medium dose (1.0%) of laminarin compared with the blank control. These results suggest that laminarin modulates the immune response and stimulates growth of the fish.


Asunto(s)
Regulación de la Expresión Génica/inmunología , Glucanos/farmacología , Perciformes/crecimiento & desarrollo , Perciformes/inmunología , ARN Mensajero/metabolismo , Animales , Proteínas Sanguíneas/metabolismo , Catalasa/sangre , Creatinina/sangre , Citocinas/sangre , Suplementos Dietéticos , Relación Dosis-Respuesta a Droga , Regulación de la Expresión Génica/efectos de los fármacos , Reacción en Cadena en Tiempo Real de la Polimerasa/veterinaria , Superóxido Dismutasa/sangre
8.
Appl Environ Microbiol ; 77(11): 3860-9, 2011 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-21498771

RESUMEN

A pilot-scale system was established to examine the feasibility of in situ U(VI) immobilization at a highly contaminated aquifer (U.S. DOE Integrated Field Research Challenge site, Oak Ridge, TN). Ethanol was injected intermittently as an electron donor to stimulate microbial U(VI) reduction, and U(VI) concentrations fell to below the Environmental Protection Agency drinking water standard (0.03 mg liter(-1)). Microbial communities from three monitoring wells were examined during active U(VI) reduction and maintenance phases with GeoChip, a high-density, comprehensive functional gene array. The overall microbial community structure exhibited a considerable shift over the remediation phases examined. GeoChip-based analysis revealed that Fe(III)-reducing bacterial (FeRB), nitrate-reducing bacterial (NRB), and sulfate-reducing bacterial (SRB) functional populations reached their highest levels during the active U(VI) reduction phase (days 137 to 370), in which denitrification and Fe(III) and sulfate reduction occurred sequentially. A gradual decrease in these functional populations occurred when reduction reactions stabilized, suggesting that these functional populations could play an important role in both active U(VI) reduction and maintenance of the stability of reduced U(IV). These results suggest that addition of electron donors stimulated the microbial community to create biogeochemical conditions favorable to U(VI) reduction and prevent the reduced U(IV) from reoxidation and that functional FeRB, SRB, and NRB populations within this system played key roles in this process.


Asunto(s)
Bacterias/clasificación , Bacterias/crecimiento & desarrollo , Biodegradación Ambiental , Biodiversidad , Microbiología del Suelo , Contaminantes Radiactivos del Suelo/metabolismo , Uranio/metabolismo , Bacterias/metabolismo , Etanol/metabolismo , Compuestos Férricos/metabolismo , Análisis por Micromatrices , Nitratos/metabolismo , Sulfatos/metabolismo , Estados Unidos
9.
ISME J ; 1(1): 67-77, 2007 May.
Artículo en Inglés | MEDLINE | ID: mdl-18043615

RESUMEN

Owing to their vast diversity and as-yet uncultivated status, detection, characterization and quantification of microorganisms in natural settings are very challenging, and linking microbial diversity to ecosystem processes and functions is even more difficult. Microarray-based genomic technology for detecting functional genes and processes has a great promise of overcoming such obstacles. Here, a novel comprehensive microarray, termed GeoChip, has been developed, containing 24,243 oligonucleotide (50 mer) probes and covering >10,000 genes in >150 functional groups involved in nitrogen, carbon, sulfur and phosphorus cycling, metal reduction and resistance, and organic contaminant degradation. The developed GeoChip was successfully used for tracking the dynamics of metal-reducing bacteria and associated communities for an in situ bioremediation study. This is the first comprehensive microarray currently available for studying biogeochemical processes and functional activities of microbial communities important to human health, agriculture, energy, global climate change, ecosystem management, and environmental cleanup and restoration. It is particularly useful for providing direct linkages of microbial genes/populations to ecosystem processes and functions.


Asunto(s)
Ambiente , Microbiología Ambiental , Análisis por Micromatrices/métodos , Biodegradación Ambiental , Carbono/metabolismo , Metales/metabolismo , Nitrógeno/metabolismo , Sondas de Oligonucleótidos , Oxidación-Reducción , Fósforo/metabolismo , Sulfatos/metabolismo
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