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Liver fibrosis is a critical factor in the advancement of nonalcoholic fatty liver disease towards cirrhosis. There is limited research exploring the association between obstructive sleep apnea (OSA) and liver fibrosis among community populations. The present study aimed to assess the association between sleep apnea (SA) and liver fibrosis based on the National Health and Nutrition Examination Survey (NHANES). Data were acquired from NHANES survey cycle 2017 to 2020. We assessed liver fibrosis by the median values of liver stiffness measurement (LSM). The diagnosis of SA was based on participants' response to sleep questionnaire. Univariate and multivariate logistic regression were used to validate the association of SA and liver fibrosis. A total of 7615 participants were included in this study. The LSM level of SA group was significantly higher than non-SA group. The proportion of liver fibrosis in SA group was markedly higher than that in non-SA group (14.0% vs 7.3%, Pâ <â .001). Univariate logistic analysis showed that SA was positively associated with liver fibrosis (ORâ =â 2.068, 95%CIâ =â 1.715-2.494, Pâ <â .001). Further multivariate logistic analysis revealed that SA was independently associated with increased risk of liver fibrosis after adjusting for confounding factors (ORâ =â 1.277, 95%CIâ =â 1.003-1.625, Pâ =â .048). The current study demonstrated an independent association between self-reported SA and increased risk of ultrasound-defined liver fibrosis in community-based sample.
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Cirrosis Hepática , Encuestas Nutricionales , Ultrasonografía , Humanos , Masculino , Femenino , Cirrosis Hepática/epidemiología , Cirrosis Hepática/diagnóstico por imagen , Cirrosis Hepática/complicaciones , Persona de Mediana Edad , Adulto , Síndromes de la Apnea del Sueño/epidemiología , Factores de Riesgo , Estudios Transversales , Anciano , Apnea Obstructiva del Sueño/epidemiología , Apnea Obstructiva del Sueño/complicacionesRESUMEN
Climate change, microbial endophytes, and local plants can affect the establishment and expansion of invasive species, yet no study has been performed to assess these interactions. Using a growth chamber, we integrated the belowground (rhizosphere soils) and aboveground (mixture of mature leaf and leaf litter) microbiota into an experimental framework to evaluate the impacts of four native plants acting as microbial inoculation sources on endophyte assembly and growth of the invasive plant Ageratina adenophora in response to drought stress and temperature change. We found that fungal and bacterial enrichment in the leaves and roots of A. adenophora exhibited distinct patterns in response to climatic factors. Many fungi were enriched in roots in response to high temperature and drought stress; in contrast, many bacteria were enriched in leaves in response to low temperature and drought stress. Inoculation of microbiota from phylogenetically close native plant species (i.e., Asteraceae Artemisia atrovirens) causes the recipient plant A. adenophora (Asteraceae) to enrich dominant microbial species from inoculation sources, which commonly results in a lower dissimilar endophytic microbiota and thus produces more negative growth effects when compared to non-Asteraceae inoculations. Drought, microbial inoculation source, and temperature directly impacted the growth of A. adenophora. Both drought and inoculation also indirectly impacted the growth of A. adenophora by changing the root endophytic fungal assembly. Our data indicate that native plant identity can greatly impact the endophyte assembly and host growth of invasive plants, which is regulated by drought and temperature.IMPORTANCEThere has been increasing interest in the interactions between global changes and plant invasions; however, it remains to quantify the role of microbial endophytes in plant invasion with a consideration of their variation in the root vs leaf of hosts, as well as the linkages between microbial inoculations, such as native plant species, and climatic factors, such as temperature and drought. Our study found that local plants acting as microbial inoculants can impact fungal and bacterial enrichment in the leaves and roots of the invasive plant Ageratina adenophora and thus produce distinct growth effects in response to climatic factors; endophyte-mediated invasion of A. adenophora is expected to operate more effectively under favorable moisture. Our study is important for understanding the interactions between climate change, microbial endophytes, and local plant identity in the establishment and expansion of invasive species.
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Ageratina , Asteraceae , Endófitos/fisiología , Plantas/microbiología , Ageratina/fisiología , Especies Introducidas , Bacterias , Raíces de Plantas/microbiología , Microbiología del SueloRESUMEN
After reviewing and evaluating the Discipline History of Acupuncture and Moxibustion in China, the authors concludes that this book has the following characteristics: the scientific research focuses on the combination of internal and external history, and the conclusions are rigorous; the narrative style and structure featured by the division of discipline history of ancient times, modern times and current times are quite characteristic and enlightening; the reference materials are detailed and advanced, which showes profound thoughts and concerns about the difficulties and challenges faced by the development of acupuncture and moxibustion discipline and the internal path selection of acupuncture and moxibustion research. In addition, this book discusses the unique importance of the cultural attribute behind acupuncture and moxibustion technology in the process of theoretical research of acupuncture and moxibustion.
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Terapia por Acupuntura , Moxibustión , China , Libros , CabezaRESUMEN
As the greatest defense organ of the body, the skin is exposed to endogenous and external stressors that produce reactive oxygen species (ROS). When the antioxidant system of the body fails to eliminate ROS, oxidative stress is initiated, which results in skin cellular senescence, inflammation, and cancer. Two main possible mechanisms underlie oxidative stress-induced skin cellular senescence, inflammation, and cancer. One mechanism is that ROS directly degrade biological macromolecules, including proteins, DNA, and lipids, that are essential for cell metabolism, survival, and genetics. Another one is that ROS mediate signaling pathways, such as MAPK, JAK/STAT, PI3K/AKT/mTOR, NF-κB, Nrf2, and SIRT1/FOXO, affecting cytokine release and enzyme expression. As natural antioxidants, plant polyphenols are safe and exhibit a therapeutic potential. We here discuss in detail the therapeutic potential of selected polyphenolic compounds and outline relevant molecular targets. Polyphenols selected here for study according to their structural classification include curcumin, catechins, resveratrol, quercetin, ellagic acid, and procyanidins. Finally, the latest delivery of plant polyphenols to the skin (taking curcumin as an example) and the current status of clinical research are summarized, providing a theoretical foundation for future clinical research and the generation of new pharmaceuticals and cosmetics.
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Carcinogénesis , Senescencia Celular , Inflamación , Estrés Oxidativo , Polifenoles , Humanos , Antioxidantes/farmacología , Antioxidantes/uso terapéutico , Senescencia Celular/fisiología , Curcumina/farmacología , Inflamación/metabolismo , Neoplasias/metabolismo , Fosfatidilinositol 3-Quinasas/metabolismo , Polifenoles/farmacología , Polifenoles/uso terapéutico , Especies Reactivas de Oxígeno/metabolismoRESUMEN
An oxidative dehydrogenative coupling of thiols with alkanes via direct C(sp3)-H bond functionalization to form a new C-S bond and SâO double bond was developed. The present reaction features the use of readily available reagents and high step- and atom-efficiency, thus providing an efficient access to sulfoxides. A possible mechanism is proposed.
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BACKGROUND: Cardiac troponins are highly sensitive and specific biomarkers for cardiac injury. Previous studies evaluating the effect of positive airway pressure (PAP) on cardiac troponins in patients with sleep-disordered breathing (SDB) have yielded conflicting results. The meta-analysis was performed to examine the effect of PAP on cardiac troponins in SDB patients. METHODS: PubMed, Web of Science, and EMBASE before September 2021 on original English language studies were searched. The data on cardiac troponins in both baseline and post-PAP treatment were extracted from all studies. The data on the change of cardiac troponins in both PAP and control group were extracted from randomized controlled trials. Standardized mean difference (SMD) was used to synthesize quantitative results. RESULTS: A total of 11 studies were included. PAP treatment was not associated with a significant change in cardiac troponin T between the baseline and post-PAP treatment (SMD = -0.163, 95% confidence interval [CI] = -0.652 to 0.326, z = 0.65, p = .514). The pooled estimate of SMD of cardiac troponin I between the pre- and post-PAP treatment was 0.287, and the 95% CI was -0.586 to 1.160 (z = 0.64, p = .519). The pooled SMD of change of cardiac troponin T between the PAP group and control group was -0.473 (95% CI = -1.198 to 0.252, z = 1.28, p = .201). CONCLUSIONS: This meta-analysis revealed that PAP treatment was not associated with any change of cardiac troponin in SDB patients.
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Síndromes de la Apnea del Sueño , Troponina T , Biomarcadores , Presión de las Vías Aéreas Positiva Contínua/métodos , Humanos , Síndromes de la Apnea del Sueño/complicaciones , Síndromes de la Apnea del Sueño/diagnóstico , Síndromes de la Apnea del Sueño/terapia , Troponina IRESUMEN
In this study, ultrasonic-assisted cellulase extraction (UCE) was applied to extract flavonoids and polyphenols from the Nymphaea hybrid flower. The extraction conditions were optimized using the response surface method (RSM) coupled with a Box-Behnken design. The crude extract of Nymphaea hybrid (NHE) was further purified using AB-8 macroporous resins, and the purified extract (NHEP) was characterized by FTIR and HPLC. In vitro activity determination by chemical method showed that NHEP displayed strong free radical scavenging abilities against the DPPH and ABTS radicals, good reduction power, and hyaluronidase inhibition. The cell viability by CCK-8 assays showed that NHEP had no significant cytotoxicity for B16 and HaCaT cells when the concentration was below 100 µg/mL and 120 µg/mL, respectively. NHEP with a concentration of 20-160 µg/mL can more effectively reduce the ROS level in H2O2 damaged HaCaT cells compared with 10 µg/mL of VC. The 40 µg/mL of NHEP had similar activity against intracellular melanin production in the B16 melanoma cells compared with 20 µg/mL Kojic acid. Good activities of antioxidation, whitening and protective effect against H2O2-induced oxidative damage promote the potential for NHEP as a functional raw material in the field of cosmetics and medicine.
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Celulasa , Nymphaea , Antioxidantes/química , Antioxidantes/farmacología , Flores , Células HaCaT , Humanos , Peróxido de Hidrógeno/farmacología , Melaninas , Estrés Oxidativo , Especies Reactivas de OxígenoRESUMEN
Vibrational properties associated with the intra- and intermolecular bonding of the crystalline Dibenz[a,h]anthracene at low temperatures are investigated by Raman scattering. A complete characterization of phonon spectra is given for this material. In the 120-150 K temperature region, several lattice modes show abrupt changes of splitting and the discontinuities in the temperature shift, but no emergence of new modes. Moreover, the intensity ratio of I68/38 is greater than 1 below 130 K. Meanwhile, the aromatic C-C stretching modes exhibit anomalous behaviors in frequencies, widths, and intensities at about 130 K. These spectroscopic results demonstrate a disorder-order transition occurred at about 130 K. However, the modes, corresponding to C-H out-of-plane bending, C-H in-plane bending, and/or C-H rocking, have no significant change in the whole temperature range. It indicates that the transition mainly results from the change of the tilt angle between the molecules. Our work is of great significance to understand the internal vibrational properties of Dibenz[a,h]anthracene, and it also provides considerable supports for the further study of this material.
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Free radical carbochloromethylations of ortho-cyanoarylacrylamides and N-(arylsulfonyl)acrylamides have been developed by employing simple alkyl chlorides as the chloromethyl source. The transformations are characterized by wide functional group compatibility and utilizing readily available reagents, thus providing efficient methods for constructing polychloromethyl-substituted quinoline-2,4-diones and α-aryl-ß-polychloromethylated amides.
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Gynostemma pentaphyllum (Thunb.) Makino (Cucurbitaceae family) is a perennial creeping plant with a common Chinese name of "south ginseng". To date, more than 250 individual saponins with dammarane-type skeleton have been isolated from G. pentaphyllum. The purpose of this study was the isolation and structural characterization of novel, minor gypenosides from G. pentaphyllum and evaluation of their Sirt1 agonist activity. Individual saponins from G. pentaphyllum were isolated and purified by a variety of chromatography techniques, and their structures were elucidated by means of various spectroscopic analysis and comparision with the reported data. Sirt1 enzyme activity detection kit was used to preliminarily evaluate the Sirt1 agonist activity of thirty three individual saponins purified from G. pentaphyllum. Fourteen new triterpenoid saponins named gypenoside CII-CXV (1-14) along with twenty six known compounds (15-40) were isolated from G. pentaphyllum. Thirty three of all the isolates were screened for Sirt1 agonist activity, and the results showed that three dammarane-type saponins (2, 18, 37) and one cucurbitane-type saponin 33 exhibited satisfactory Sirt1 agonist activity. These findings suggested that G. pentaphyllum was worthy of further investigation to find small molecule Sirt1 agonist and facilitate their utilization as "south ginseng".
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Gynostemma/química , Saponinas/farmacología , Sirtuina 1/metabolismo , Triterpenos/farmacología , Relación Dosis-Respuesta a Droga , Humanos , Estructura Molecular , Saponinas/química , Saponinas/aislamiento & purificación , Relación Estructura-Actividad , Triterpenos/química , Triterpenos/aislamiento & purificación , DamaranosRESUMEN
A novel annulation of 2-cyanoaryl acrylamides via CâC double bond cleavage has been developed for facile and efficient access to a broad spectrum of functionalized 4-amino-2-quinolones, which are important N-heterocycles. In this transformation, the solvent THF is demonstrated to play a crucial role, and the addition of alkyl radicals to nitrile, 1,5-hydride shift, and cleavage of the C-C bond are involved in the mechanism.
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Novel decarboxylative oxyacyloxylation of propiolic acids has been developed. This reaction provides an efficient access to alkynyl-containing α-acyloxy ketones from readily available starting materials and exhibits significant functional group tolerance. Furthermore, oxyacyloxylation of terminal alkynes and aliphatic propiolic acids was also developed. A possible reaction mechanism is proposed based on mechanistic studies.
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Alquinos , Cetonas , Catálisis , Estructura MolecularRESUMEN
P3-Na0.65Mn0.5Al0.5O2 (NMAO) has been synthesized and studied as a cathode for sodium batteries, and shows anionic redox reaction (ARR) and exhibits a first charging capacity of â¼110 mA h g-1. The electrochemical mechanism of NMAO was comprehensively investigated by X-ray absorption spectroscopy (XAS), X-ray photoelectron spectroscopy (XPS), Raman spectroscopy, and density functional theory (DFT) calculations. The reversible oxygen redox behaviour is triggered by Al3+ through oxygen quasi non-bonding states generated by the relatively ionic interaction of Al and O. Furthermore, the presence of Al3+ can suppress oxygen loss in ARR. This work provides new insights into the design and mechanism of anionic redox active cathode materials.
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The Pleurotus ostreatus species complex is saprotrophic and of significant economic and ecological importance. However, species delimitation has long been problematic because of phenotypic plasticity and morphological stasis. In addition, the evolutionary history is poorly understood due to limited sampling and insufficient gene fragments employed for phylogenetic analyses. Comprehensive sampling from Asia, Europe, North and South America and Africa was used to run phylogenetic analyses of the P. ostreatus species complex based on 40 nuclear single-copy orthologous genes using maximum likelihood and Bayesian inference analyses. Here, we present a robust phylogeny of the P. ostreatus species complex, fully resolved from the deepest nodes to species level. The P. ostreatus species complex was strongly supported as monophyletic, and 20 phylogenetic species were recognized, with seven putatively new species. Data from our molecular clock analyses suggested that divergence of the genus Pleurotus probably occurred in the late Jurassic, while the most recent common ancestor of the P. ostreatus species complex diversified about 39 Ma in East Asia. Species of the P. ostreatus complex might migrate from the East Asia into North America across the North Atlantic Land Bridge or the Bering Land Bridge at different times during the late Oligocene, late Miocene and late Pliocene, and then diversified in the Old and New Worlds simultaneously through multiple dispersal and vicariance events. The dispersal from East Asia to South America in the middle Oligocene was probably achieved by a long-distance dispersal event. Intensification of aridity and climate cooling events in the late Miocene and Quaternary glacial cycling probably had a significant influence on diversification patterns of the complex. The disjunctions among East Asia, Europe, North America and Africa within Clade IIc are hypothesized to be a result of allopatric speciation. Substrate transitions to Apiaceae probably occurred no earlier than 6 Ma. Biogeographic analyses suggested that the global cooling of the late Eocene, intensification of aridity caused by rapid uplift of the QTP and retreat of the Tethys Sea in the late Miocene, climate cooling events in Quaternary glacial cycling, and substrate transitions have contributed jointly to diversification of the species complex.
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Pelvic floor disorders (PFDs) represent a group of common and frequently-occurring diseases that seriously affect the life quality of women, generally including stress urinary incontinence and pelvic organ prolapse. Surgery has been used as a treatment for PFD, but almost 30% of patients require subsequent surgery due to a high incidence of postoperative complications and high recurrence rates. Therefore, investigations of new therapeutic strategies are urgently needed. Stem cells possess strong multi-differentiation, self-renewal, immunomodulation, and angiogenesis abilities and they are able to differentiate into various cell types of pelvic floor tissues and thus provide a potential therapeutic approach for PFD. Recently, various studies using different autologous stem cells have achieved promising results by improving the pelvic ligament and muscle regeneration and conferring the tissue elasticity and strength to the damaged tissue in PFD, as well as reduced inflammatory reactions, collagen deposition, and foreign body reaction. However, with relatively high rates of complications such as bladder stone formation and wound infections, further studies are necessary to investigate the role of stem cells as maintainers of tissue homeostasis and modulators in early interventions including therapies using new stem cell sources, exosomes, and tissue-engineering combined with stem cell-based implants, among others. This review describes the types of stem cells and the possible interaction mechanisms in PFD treatment, with the hope of providing more promising stem cell treatment strategies for PFD in the future.
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Emerging evidence suggests that both apoptosis and autophagy contribute to global cerebral ischemiareperfusion (GCIR)induced neuronal death, which results from cardiac arrest (CA). However, the mechanism of how GCIR may affect the balance between apoptosis and autophagy resulting from CA remains to be elucidated. Additionally, the role of adiponectin (APN) in reversing the apoptosis and autophagy induced by GCIR following cardiac arrestcardiopulmonary resuscitation (CACPR) is unclear. Thus, the aim of the present study was to investigate how GCIR affect the apoptosis and autophagy in response to CA and to clarify whether APN may alter the apoptosis and autophagy of neuronal death in GCIRinjured brain postCACPR. Using normal controls (Sham group) and two experimental groups [CACPRinduced GCIR injury (PCAS) group and exogenous treatment with adiponectin postCACPR (APN group)], it was demonstrated that both apoptosis and autophagy were observed simultaneously in the brain subjected to GCIR, but apoptosis appeared to be more apparent. Exogenous administration of APN significantly reduced the formation of malondialdehyde, a marker of oxidative stress and increased the expression of superoxide dismutase, an antioxidative enzyme, resulting in the stimulation of autophagy, inhibition of apoptosis and reduced brain tissue injury (P<0.05 vs. PCAS). APN treatment increased the expression of APN receptor 1 (AdipR1) and the phosphorylation of AMPactivated protein kinase (AMPK; Ser182) in brain tissues. In conclusion, GCIR induced apoptosis and inhibited autophagy, contributing to brain injury in CACPR. By contrast, APN reduced the brain injury by reversing the changes of neuronal autophagy and apoptosis induced by GCIR. The possible mechanism might owe to its effects on the activation of AMPK after combining with AdipR1 on neurons, which suggests a novel intervention against GCIR injury in CACPR conditions.
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Adiponectina/farmacología , Apoptosis/efectos de los fármacos , Autofagia/efectos de los fármacos , Isquemia Encefálica/metabolismo , Daño por Reperfusión/metabolismo , Transducción de Señal/efectos de los fármacos , Proteínas Quinasas Activadas por AMP/metabolismo , Adiponectina/sangre , Animales , Encéfalo/citología , Encéfalo/efectos de los fármacos , Encéfalo/metabolismo , Isquemia Encefálica/tratamiento farmacológico , Isquemia Encefálica/etiología , Reanimación Cardiopulmonar/efectos adversos , Modelos Animales de Enfermedad , Paro Cardíaco/complicaciones , Masculino , Ratones , Ratones Endogámicos C57BL , Neuronas/citología , Neuronas/efectos de los fármacos , Neuronas/metabolismo , Estrés Oxidativo/efectos de los fármacos , Receptores de Adiponectina/biosíntesis , Receptores de Adiponectina/metabolismo , Daño por Reperfusión/tratamiento farmacológicoRESUMEN
Local pathogens can accumulate as asymptomatic endophytes, making it difficult to detect the impacts of invasive species as propagators of disease in the invaded range. We used the invasive plant Ageratina adenophora to assess such accumulation. We intensively collected foliar fungal endophytes and leaf spot pathogens of A. adenophora and co-occurring neighbours and performed an inoculation experiment to evaluate their pathogenicity and host range. Ageratina adenophora harboured diverse necrotrophic pathogens; its communities of endophytes and leaf spot pathogens were different in composition and shared only a small number of fungal species. In the pathogen communities of local plant hosts, 21% of the operational taxonomic units (OTUs), representing 50% of strains, also occurred as leaf spot pathogens and/or endophytes of A. adenophora. The local pathogen community was more similar to the endophytes than to the pathogens of A. adenophora. The inoculation experiment showed that local pathogens could infect A. adenophora leaves asymptomatically and that local plant hosts were susceptible to both A. adenophora endophytes and pathogens. Ageratina adenophora is a highly competent host for local pathogens, and its asymptomatic latent pathogens are fungi primarily shared with local neighbours. This poses challenges for understanding the long-term ecological consequences of plant invasion.
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Ageratina , Endófitos , Hongos , Especies IntroducidasRESUMEN
Within the family Entolomataceae, many reports of Entoloma and Rhodocybe have been published, but few reports on Clitopilus and allied genera are available. In this study, Clitopilus, Clitocella, and Clitopilopsis from China were studied by morphological and phylogenetic methods. Portions of nuc 28S rDNA (28S), RNA polymerase II second largest subunit (rpb2), translation elongation factor 1-alpha (tef1), and ATPase subunit 6 (atp6), were employed to elucidate the relationships of Clitopilus and allies. Results indicate that Clitopilus should be divided into three sections, namely, sect. Clitopilus, sect. Scyphoides, and sect. Crispi, the last of which is newly described. In total, 17 species of Clitopilus, Clitocella, and Clitopilopsis are found in China; 14 species belong to Clitopilus, of which 5 are new: C. yunnanensis, C. brunniceps, C. rugosiceps, C. sinoapalus, and C. umbilicatus. Two species of Clitocella, including one new species, Clitocella orientalis, are described. One new species of Clitopilopsis, namely, Clitopilopsis albida, is proposed.
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Agaricales/clasificación , Agaricales/citología , Agaricales/genética , Agaricales/aislamiento & purificación , China , Genes Fúngicos , Tipificación de Secuencias Multilocus , FilogeniaRESUMEN
Exophiala pisciphila is one of the dominant dark septate endophytes (DSEs) colonizing metal-polluted slag heaps in southwest China. It shows numerous super-metal-tolerant characteristics, but the molecular mechanisms involved remain largely unknown. In the present study, the functional roles of a speciï¬c set of ATP-binding cassette (ABC) transporters in E. pisciphila were characterized. In total, 26 EpABC genes belonging to 6 subfamilies (ABCA to ABCG) were annotated in previous transcriptome sequencing libraries, and all were regulated by metal ions (Pb, Zn, and Cd), which was dependent on the metal species and/or concentrations tested. The results from the heterologous expression of 3 representative EpABC genes confirmed that the expression of EpABC2.1, EpABC3.1, or EpABC4.1 restored the growth of metal-sensitive mutant Saccharomyces cerevisiae strains and significantly improved the tolerance of Arabidopsis thaliana to Pb, Zn, and Cd. Interestingly, the expression of the 3 EpABC genes further altered metal (Pb, Zn, and Cd) uptake and accumulation and promoted growth by alleviating the inhibitory activity in yeast and thale cress caused by toxic ions. These functions along with their vacuolar location suggest that the 3 EpABC transporters may enhance the detoxification of vacuolar compartmentation via transport activities across their membranes. In conclusion, the 26 annotated EpABC transporters may play a major role in maintaining the homeostasis of various metal ions in different cellular compartments, conferring an extreme adaptative advantage to E. pisciphila in metal-polluted slag heaps.IMPORTANCE Many ABC transporters and their functions have been identified in animals and plants. However, little is known about ABC genes in filamentous fungi, especially DSEs, which tend to dominantly colonize the roots of plants growing in stressed environments. Our results deepen the understanding of the function of the ABC genes of a super-metal-tolerant DSE (E. pisciphila) in enhancing its heavy metal resistance and detoxification. Furthermore, the genetic resources of DSEs, e.g., numerous EpABC genes, especially from super-metal-tolerant strains in heavy metal-polluted environments, can be directly used for transgenic applications to improve tolerance and phytoextraction potential.
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Transportadoras de Casetes de Unión a ATP/genética , Arabidopsis/metabolismo , Exophiala/crecimiento & desarrollo , Proteínas Fúngicas/genética , Saccharomyces cerevisiae/metabolismo , Contaminantes del Suelo/metabolismo , Transportadoras de Casetes de Unión a ATP/metabolismo , Arabidopsis/genética , Cadmio/metabolismo , Exophiala/metabolismo , Proteínas Fúngicas/metabolismo , Plomo/metabolismo , Microorganismos Modificados Genéticamente/genética , Microorganismos Modificados Genéticamente/metabolismo , Plantas Modificadas Genéticamente/genética , Plantas Modificadas Genéticamente/metabolismo , Saccharomyces cerevisiae/genética , Zinc/metabolismoRESUMEN
Metal-organic framework (MOF)-based materials possess numerous attractive characteristics; however, the application of MOF-based photocatalysts in the area of visible-light photocatalytic H2 evolution is still in its infancy. Herein, we develop a series of novel UiO-66-NH2-based composites with embedded NiO nanoparticles via solvothermal treatment and subsequent calcination. Their characterizations demonstrate intimate lattice-level contacts between UiO-66-NH2 photocatalysts and NiO nanoparticles. By optimizing each component, even without noble metal loading, the U6N-NiO-2 sample (the weight ratio of NiO to U6N-NiO-2 is theoretically calculated to be ca. 10 wt%) with 15 mg eosin Y as a sensitizer causes an enhanced H2 generation rate of 2561.32 µmol h-1 g-1 under visible-light irradiation using TEOA as a sacrificial reagent; furthermore, its corresponding quantum efficiency is as high as 6.4% at 420 nm. The H2 evolution activity of U6N-NiO-2 is about 5 times higher than that of the UiO-66-NH2 photocatalyst (denoted as U6N) and 23 times higher than that of U6N-NiO-2 without sensitizer. It is demonstrated that the high efficiency originates from the visible-light generated electrons of eosin Y and UiO-66-NH2, the efficient separation of carriers by the cascaded band structure and more negative CB of NiO as well as the good dispersion of NiO nanoparticles on the octahedral skeleton. This study provides new insights for the design of MOF-based materials without noble metal loading for visible-light photocatalytic H2 evolution.