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Copper contaminant generated from mining and industrial smelting poses potential risks to human health. Biochar, as a low-energy and cost-effective biomaterial, holds value in Cu remediation. Spectral Induced Polarization (SIP) technique is employed in this study to monitor the Cu remediation processes of by biochar in column experiments. Cation exchange at low Cu2+ concentrations and surface complexation at high Cu2+ concentrations are identified as the major mechanisms for copper retention on biochar. The normalized chargeability (mn) from SIP signals linearly decreased (R2 = 0.776) with copper retention under 60 mg/L Cu influent; while mn linearly increases (R2 = 0.907, 0.852) under high 300 and 700 mg/L Cu influents. The characteristic polarizing unit sizes (primarily the pores adsorbing Cu2+) calculated from Schwartz equation match well with experimental results by mercury intrusion porosimetry (MIP). It is revealed that Cu2+ was driven to small pores (â¼3 µm) given high concentration gradient (influent Cu2+ concentration of 700 mg/L). Comparing to activated carbon, biochar is identified as an ideal adsorbent for Cu remediation, given its high adsorption capacity, cost-effectiveness, carbon-sink ability, and high sensitivity to SIP responses - the latter facilitates its performance assessment.
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Carvão Vegetal , Cobre , Cobre/química , Carvão Vegetal/química , Adsorção , Recuperação e Remediação Ambiental/métodos , Poluentes Químicos da Água/química , Poluentes Químicos da Água/análiseRESUMO
Independence among leaf economics, leaf hydraulics and leaf size confers plants great capability in adapting to heterogeneous environments. However, it remains unclear whether the independence of the leaf traits revealed across species still holds within species, especially under stressed conditions. Here, a suite of traits in these dimensions were measured in leaves and roots of a typical mangrove species, Ceriops tagal, which grows in habitats with a similar sunny and hot environment but different soil salinity in southern China. Compared with C. tagal under low soil salinity, C. tagal under high soil salinity had lower photosynthetic capacity, as indicated directly by a lower leaf nitrogen concentration and higher water use efficiency, and indirectly by a higher investment in defense function and thinner palisade tissue; had lower water transport capacity, as evidenced by thinner leaf minor veins and thinner root vessels; and also had much smaller single leaf area. Leaf economics, hydraulics and leaf size of the mangrove species appear to be coordinated as one trait dimension, which likely stemmed from co-variation of soil water and nutrient availability along the salinity gradient. The intraspecific leaf trait relationship under a stressful environment is insightful for our understanding of plant adaption to the multifarious environments.
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The pouring time interval is the decisive factor of dual-liquid casting for bimetallic productions. Traditionally, the pouring time interval is fully determined by the operator's experience and on-site observation. Thus, the quality of bimetallic castings is unstable. In this work, the pouring time interval of dual-liquid casting for producing low alloy steel/high chromium cast iron (LAS/HCCI) bimetallic hammerheads is optimized via theoretical simulation and experimental verification. The relevancies of interfacial width and bonding strength to pouring time interval are, respectively, established. The results of bonding stress and interfacial microstructure indicate that 40 s is the optimum pouring time interval. The effects of interfacial protective agent on interfacial strength-toughness are also investigated. The addition of the interfacial protective agent yields an increase of 41.5% in interfacial bonding strength and 15.6% in toughness. The optimum dual-liquid casting process is used to produce LAS/HCCI bimetallic hammerheads. Samples cut from these hammerheads show excellent strength-toughness (1188 Mpa for bonding strength and 17 J/cm2 for toughness). The findings could be a reference for dual-liquid casting technology. They are also helpful for understanding the formation theory of the bimetal interface.
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The cortex (i.e., absorptive tissue) and stele (transportive vascular tissue) are fundamental to the function of plant roots. Unraveling how these anatomical structures are assembled in absorptive roots is essential for our understanding of plant ecology, physiology, and plant responses to global environmental changes. In this review, we first compile a large data set on anatomical traits in absorptive roots, including cortex thickness and stele radius, across 698 observations and 512 species. Using this data set, we reveal a common root allometry in absorptive root structures, i.e., cortex thickness increases much faster than stele radius with increasing root diameter (hereafter, root allometry). Root allometry is further validated within and across plant growth forms (woody, grass, and liana species), mycorrhiza types (arbuscular mycorrhiza, ectomycorrhiza, and orchid mycorrhizas), phylogenetic gradients (from ferns to Orchidaceae), and environmental change scenarios (e.g., elevation of atmospheric CO2 concentration and nitrogen fertilization). These findings indicate that root allometry is common in plants. Importantly, root allometry varies greatly across species. We then summarize recent research on the mechanisms of root allometry and potential issues regarding these mechanisms. We further discuss ecological and evolutionary implications of root allometry. Finally, we propose several important research directions that should be pursued regarding root allometry.
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Objective To explore the effects of interleukin-6 (IL-6) gene knockout on the cognitive function and pathological changes in 5×FAD transgenic mice of Alzheimer's disease.Methods IL-6+/- mice were crossed with 5×FAD mice to establish the 5×FAD;IL-6-/- mouse model,and 3-month-old and 10-month-old mice were selected for experiments.The cognitive function of mice was detected by behavioral tests,and HE staining and ß-amyloid (Aß) immunohistochemical staining were performed to detect the pathological changes of mouse brain tissue.Results The number of 5×FAD;IL-6-/- model mice (3 months old,n=20;10 months old,n=5) and 5×FAD littermate control (3 months old,n=26;10 months old,n=24) conformed to the Mendel's law.Compared with that of the 5×FAD mice at the same age,the discrimination ratio of 3-month-old 5×FAD;IL-6-/- mice increased in the novel object recognition test (q=3.890,P=0.002).Morris water maze test results showed that the 3-month-old 5×FAD;IL-6-/- mice had longer time spent in target quadrant (q=3.797,P=0.012) and more times of crossing platform (q=2.505,P=0.017) than the 5×FAD mice at the same age.The results of immunohistochemical staining showed that IL-6 knockout reduced the Aß deposition in the hippocampus (q=13.490,P=0.002;q=45.680,P<0.001) and cortex (q=16.830,P=0.001;q=14.180,P=0.001) of 5×FAD mice.Conclusion IL-6 gene knockout can significantly improve the spatial memory and reduce the Aß deposition in the brain of 5×FAD mice.
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Doença de Alzheimer , Doença de Alzheimer/genética , Animais , Cognição , Modelos Animais de Doenças , Flavina-Adenina Dinucleotídeo , Técnicas de Inativação de Genes , Interleucina-6 , Camundongos , Camundongos KnockoutRESUMO
Objectives: In this study, we aimed to examine the efficacy of micro ribonucleic acid (miRNA)-23a-5p in gouty arthritis and to investigate its possible mechanism. Materials and methods: Gouty arthritis in rat was established by intraarticular injection of 0.2 mL monosodium urate crystal (20 mg/mL) inside knee joint cavity. THP-1 cell was induced using lipopolysaccharides (LPS) for in vitro model. Results: Serum miRNA-23a-5p expression levels were increased in rats of gouty arthritis. However, overexpression of miRNA-23a-5p promoted inflammation and induced myeloid differential protein-88 (MyD88)/nuclear factor-kappa B (NF-κB) pathway by induction toll-like receptor-2 (TLR2) in vitro. The inhibition of TLR2 attenuated the pro-inflammation effects of miRNA-23a-5p in inflammation in in vitro model of gouty arthritis. Conclusion: Our findings demonstrate that miRNA-23a-5p is a biomarker for gouty arthritis and promotes inflammation in rats of gouty arthritis via MyD88/NF-κB pathway by targeting TLR2.
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In Situ transformed carbon fibers/Al2O3 ceramic matrix nanocomposites with Cao-MgO-SiO2 sintering agent were prepared by hot-pressed sintering technology in vacuum. In the sintering process, pre-oxidized polyacrylonitrile fibers (below named as pre-oxidized PAN fibers) were used as the precursors of In Situ transformed carbon fibers. The micro/nanostructure of composites and interface between In Situ transformed carbon fibers and matrix were investigated, as well as the properties of composites. The results showed that the composites could be sintered well at a relatively low temperature of 1650 °C. During the sintering, the precursors, pre-oxidized PAN fibers, were In Situ transformed into carbon fibers, and the In Situ transformed carbon fibers had the graphitelike structure along the fiber axial direction. The carbon atoms arrangement in the surface layer of the fiber was more orderly than the core. A typical diffraction peak of carbon fiber at 26°, which corresponded to the (002) crystal plane, was observed, and the inter-planar spacing was approximately 0.34 nm. The CaO-MgO-SiO2 sintering agent formed MgAl2O4 and CaAl2Si2O8 phases in the interface between In Situ transformed carbon fibers and matrix, therefore improving the interface bonding, and thereby modifying the mechanical properties of the composites.
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The effects of exogenous methyl jasmonate (MeJA) on the resistance levels to quinclorac and endogenous hormone levels were examined using the resistant and sensitive biotypes of barnyardgrass with the same genetic background. The results showed that exogenous MeJA could significantly increase the resistance of resistant plants to quinclorac, but did not affect the resistance of sensitive plants. There were significant differences in the contents of indole-3-acetic acid (IAA), abscisic acid (ABA), salicylic acid (SA), and jasmonic acid (JA) among the tested materials. Quinclorac treatment could significantly increase the contents of ABA, SA, and JA in barnyardgrass, with stronger increase of ABA and JA contents in the sensitive plants. Exogenous MeJA could significantly enhance the induction of ABA and JA contents by quinclorac, especially in the sensitive biotypes. These results showed that rapid hormone variations in sensitive plants inhibited their response to herbicide, while gentle hormone variations endowed resistant plants with a strong adapta-bility to herbicide, which closely related to the enhanced resistance by MeJA. ABA and JA hormone signals might play an important role in the resistance of barnyardgrass to quinclorac stress.
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Echinochloa , Quinolinas , Acetatos , Ciclopentanos , OxilipinasRESUMO
Two-photon fluorescence (TPF) imaging holds great promise for real-time monitoring of cerebral ischemia-reperfusion injury, which is important for the clinical diagnosis of stroke. However, biocompatible and photostable NIR-emitting probes for TPF imaging of ischemic stroke are lacking. Herein, we report the first NIR-emitting TPF probe (named NESPN) prepared using semiconducting polymers for TPF imaging of cerebral ischemia. By virtue of its excellent biocompatibility with the nervous system and bright fluorescence NIR emission, NESPN enables the real-time imaging of mouse brain vasculature with micrometer-scale spatial resolution, realizing clear visualization of ultrafine capillaries (â¼3.16 µm). Moreover, NESPN can be utilized in the dynamic monitoring of cerebral blood flow velocity. Microangiography using NESPN was successfully used to indicate the openness of the penumbra area in the mouse brain stroke model. More importantly, this technique allows us to continuously monitor the whole process of ischemic stroke and subsequent reperfusion. This work provides a new and versatile tool for vascular research and diagnosis of vascular diseases.
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Encéfalo/diagnóstico por imagem , Circulação Cerebrovascular , AVC Isquêmico/diagnóstico por imagem , Nanopartículas/administração & dosagem , Polímeros/administração & dosagem , Traumatismo por Reperfusão/diagnóstico por imagem , Animais , Encéfalo/irrigação sanguínea , Fluorenos/administração & dosagem , Corantes Fluorescentes/administração & dosagem , Camundongos , Imagem Óptica/métodos , Semicondutores , Tiadiazóis/administração & dosagem , Imagem Corporal TotalRESUMO
Here, we have synthesized and characterized a novel activatable photosensitizer (PS) 8a in which two well-designed boron dipyrromethene (BODIPY) derivatives are utilized as the photosensitizing fluorophore and quencher respectively, which are connected by a disulfide linker via two successive Cu (Ð) catalyzed click reactions. The fluorescence emission and singlet oxygen production of 8a are suppressed via intramolecular fluorescence resonance energy transfer (FRET) from the excited BODIPY-based PS part to quencher unit, but both of them can be simultaneously switched on by cancer-related biothiol glutathione (GSH) in phosphate buffered saline (PBS) solution with 0.05% Tween 80 as a result of cleavage of disulfide. Also, 8a exhibits a bright fluorescence image and a substantial ROS production in A549 human lung adenocarcinoma, HeLa human cervical carcinoma and H22 mouse hepatoma cells having a relatively high concentration of GSH, thereby leading to a significant photocytotoxicity, with IC50 values as low as 0.44 µM, 0.67 µM and 0.48 µM, respectively. In addition, the photosensitizer can be effectively activated and imaged in H22 transplanted hepatoma tumors of mice and shows a strong inhibition on tumor growth. All these results suggest that such a GSH-responsive photosensitizer based on FRET mechanism may provide a new strategy for tumor-targeted and fluorescence imaging-guided cancer therapy.
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Antineoplásicos/farmacologia , Transferência Ressonante de Energia de Fluorescência , Glutationa/química , Imagem Óptica , Fotoquimioterapia , Fármacos Fotossensibilizantes/farmacologia , Animais , Antineoplásicos/síntese química , Antineoplásicos/química , Compostos de Boro/síntese química , Compostos de Boro/química , Compostos de Boro/farmacologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Feminino , Humanos , Camundongos , Camundongos Endogâmicos , Estrutura Molecular , Neoplasias Experimentais/tratamento farmacológico , Neoplasias Experimentais/patologia , Fármacos Fotossensibilizantes/síntese química , Fármacos Fotossensibilizantes/química , Porfobilinogênio/análogos & derivados , Porfobilinogênio/síntese química , Porfobilinogênio/química , Porfobilinogênio/farmacologia , Relação Estrutura-AtividadeRESUMO
BACKGROUND: Although diabetic kidney disease demonstrates both familial clustering and single nucleotide polymorphism heritability, the specific genetic factors influencing risk remain largely unknown. METHODS: To identify genetic variants predisposing to diabetic kidney disease, we performed genome-wide association study (GWAS) analyses. Through collaboration with the Diabetes Nephropathy Collaborative Research Initiative, we assembled a large collection of type 1 diabetes cohorts with harmonized diabetic kidney disease phenotypes. We used a spectrum of ten diabetic kidney disease definitions based on albuminuria and renal function. RESULTS: Our GWAS meta-analysis included association results for up to 19,406 individuals of European descent with type 1 diabetes. We identified 16 genome-wide significant risk loci. The variant with the strongest association (rs55703767) is a common missense mutation in the collagen type IV alpha 3 chain (COL4A3) gene, which encodes a major structural component of the glomerular basement membrane (GBM). Mutations in COL4A3 are implicated in heritable nephropathies, including the progressive inherited nephropathy Alport syndrome. The rs55703767 minor allele (Asp326Tyr) is protective against several definitions of diabetic kidney disease, including albuminuria and ESKD, and demonstrated a significant association with GBM width; protective allele carriers had thinner GBM before any signs of kidney disease, and its effect was dependent on glycemia. Three other loci are in or near genes with known or suggestive involvement in this condition (BMP7) or renal biology (COLEC11 and DDR1). CONCLUSIONS: The 16 diabetic kidney disease-associated loci may provide novel insights into the pathogenesis of this condition and help identify potential biologic targets for prevention and treatment.
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Autoantígenos/genética , Colágeno Tipo IV/genética , Diabetes Mellitus Tipo 1/genética , Nefropatias Diabéticas/genética , Estudo de Associação Genômica Ampla , Membrana Basal Glomerular , Mutação , Estudos de Coortes , Feminino , Humanos , MasculinoRESUMO
(-)-Epigallocatechin-3-gallate (EGCG) found in tea is a natural activator of nuclear factor erythroid 2-related factor 2 (Nrf2), a primary regulator of the cellular defense system. The adverse health effects resulting from methylmercury (MeHg) exposure in humans are of worldwide concern. We hypothesized that EGCG could induce a Nrf2-mediated protective response to antagonize MeHg toxicity. Using the Caenorhabditis elegans (C. elegans) nematode model, we observed that EGCG activated SKN-1 (the functional ortholog of Nrf2 in C. elegans), as shown by the increased skn-1 mRNA level, induction of the gene gst-4, and enhanced SKN-1-mediated oxidative stress resistance that were indicated by elevation of total antioxidant ability and reductions in reactive oxygen species and malondialdehyde. Following exposure to MeHg, EGCG-treated C. elegans displayed increased survival rates, improved locomotion behaviors, decreased numbers of damaged neurons, and reduced oxidative damage compared to the controls. Moreover, the protective effects of EGCG against MeHg toxicity were counteracted by RNA-mediated interference of skn-1. These results demonstrated that EGCG could alleviate MeHg toxicity by upregulating the SKN-1-regulated protective response in C. elegans. Our study suggests a potentially beneficial effect of targeting Nrf2 by dietary EGCG in protecting humans against MeHg toxicity.
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Proteínas de Caenorhabditis elegans/metabolismo , Catequina/análogos & derivados , Proteínas de Ligação a DNA/metabolismo , Compostos de Metilmercúrio/toxicidade , Substâncias Protetoras/farmacologia , Fatores de Transcrição/metabolismo , Animais , Antioxidantes/metabolismo , Caenorhabditis elegans/crescimento & desenvolvimento , Catequina/farmacologia , Neurônios Dopaminérgicos/efeitos dos fármacos , Neurônios Dopaminérgicos/metabolismo , Larva/efeitos dos fármacos , Peroxidação de Lipídeos/efeitos dos fármacos , Locomoção/efeitos dos fármacos , Interferência de RNA , RNA Interferente Pequeno/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Regulação para Cima/efeitos dos fármacosRESUMO
In this study, we demonstrate a novel H2O2 activatable photosensitizer (compound 7) which contains a diiodo distyryl boron dipyrromethene (BODIPY) core and an arylboronate group that quenches the excited state of the BODIPY dye by photoinduced electron transfer (PET). The BODIPY-based photosensitizer is highly soluble and remains nonaggregated in dimethyl sulfoxide (DMSO) as shown by the intense and sharp Q-band absorption (707 nm). As expected, compound 7 exhibits negligible fluorescence emission and singlet oxygen generation efficiency. However, upon interaction with H2O2, both the fluorescence emission and singlet oxygen production of the photosensitizer can be restored in phosphate buffered saline (PBS) solution and PBS buffer solution containing 20% DMSO as a result of the cleavage of the arylboronate group. Due to the higher concentration of H2O2 in cancer cells, compound 7 even with low concentration is particularly sensitive to human cervical carcinoma (HeLa) cells (IC50 = 0.95 µM) but hardly damage human embryonic lung fibroblast (HELF) cells. The results above suggest that this novel BODIPY derivative is a promising candidate for fluorescence imaging-guided photodynamic cancer therapy.
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Boro/química , Peróxido de Hidrogênio/química , Fotoquimioterapia , Fármacos Fotossensibilizantes/química , Porfobilinogênio/análogos & derivados , Transporte Biológico , Linhagem Celular , Humanos , Estrutura Molecular , Fotoquímica , Fotoquimioterapia/métodos , Fármacos Fotossensibilizantes/síntese química , Porfobilinogênio/síntese química , Porfobilinogênio/química , Espécies Reativas de Oxigênio/metabolismo , Espectrometria de FluorescênciaRESUMO
Distinguishing structural isomers at the single-molecule level remains a challenge. We report the single-molecule recognition of two diketopyrrolopyrrole containing isomers (SDPP and SPPO) employing the mechanically controllable break junction technique. The single-molecule conductances of the two isomers are indistinguishable under normal conditions. However, reversible protonation and deprotonation of the SPPO in molecular junction result in more than 1 order of magnitude conductance change, which dramatically enhances the conductance difference between the two isomers. Theoretical study reveals that the dramatic conductance switching is due to reversible quantum interference effect. It is suggested that combination of stimuli-response and quantum interference can be an efficient strategy to enhance isomer recognition and conductance switching in single-molecule junctions.
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Scarce toxicological data are available for 2,6-dichloro-1,4-benzoquinone (DCBQ), an emerging water disinfection by-product (DBP) that is of potential public health concern. This study investigated the effects of DCBQ on the lethality, respiration rate, and DNA damage in the Caenorhabditis elegans nematode. Meanwhile, the toxic effects of five regulated DBPs, dichloroacetic acid (DCA), trichloroacetic acid (TCA), monobromoacetic acid (MBA), dibromoacetic acid (DBA), and N-nitrosodimethylamine (NDMA), have also been evaluated. The tested DBPs increased the lethality and inhibited the respiration of C. elegans with an identical order of toxicity as follows: DCBQ>MBA>DBA>DCA>TCA>NDMA. The EC50 value (median concentration causing 50% reduction in respiration compared with untreated C. elegans) is at least 30-fold lower than the corresponding LC50 value (median lethal concentration). Exposure to DCBQ and NDMA, but not to MBA, DBA, DCA, or TCA, resulted in DNA damage to C. elegans. The study suggested that DCBQ was more potent in inducing general toxicity than some regulated DBPs, and it revealed the in vivo genotoxic effect of DCBQ. Furthermore, the C. elegans-based bioassays may provide potentially useful tools for the toxicology assessment and ranking of DBPs.
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Benzoquinonas/toxicidade , Caenorhabditis elegans/efeitos dos fármacos , Desinfetantes/toxicidade , Desinfecção , Poluentes Químicos da Água/toxicidade , Animais , Bioensaio , Caenorhabditis elegans/metabolismo , Dano ao DNA , Água Potável , Dose Letal Mediana , Consumo de Oxigênio/efeitos dos fármacos , Purificação da ÁguaRESUMO
BACKGROUND: The New Cooperative Medical Scheme (NCMS) for peasantries implemented in 2003 and the Urban Resident Basic Medical Insurance (URBMI) for the urban unemployed implemented in 2007 have many similarities. They both apply the financing mode of individual premiums plus government's subsidies, and the voluntary enrollment. The Chinese government plans to integrate these two systems and build a unified basic medical insurance system for the unemployed in order to achieve the medical equity and increase the general health level. Thus, to analyze the main influencing factors of the enrollment of the urban unemployed and rural residents is very important for improving the system and securing the stability of the system during the transition. METHODS: The study uses data from the China Health and Nutrition Survey (CHNS) and adopts logistic regression models to test which factors influence the enrollment of the URBMI and the NCMS under the background of rather high enrollment rate of Chinese basic medical insurances and strong fiscal support of the Chinese government, especially whether health status or age influences enrollment of these two insurances greater. RESULTS: There is indeed some adverse selection in the URBMI and the NCMS. Whether the individual has chronic diseases have significant influence on enrollments of both the urban unemployed and rural residents, while whether the individual got ill in last four weeks just influences enrollments of the urban unemployed. Age influences enrollment greater than health status. The older the insured are, the larger the enrollment rates are. CONCLUSION: Because of the active support for basic medical insurances of the Chinese government, the enrollment performance of the urban unemployed and rural residents has already changed. When implementing the new policy, the government should pay attention to the willingness to enroll in and the change of enrollment performance of the insured. Therefore, under the policy of voluntary enrollment, every coordinated province and city should enlarge the proportion of young people to insuring group, optimizing the age structure, and the financing proportion of governments and individuals should be measured properly. With the increasing of governments' subsidies, the proportion of individual's premiums should also be increased.
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Envelhecimento/fisiologia , Nível de Saúde , Cobertura do Seguro/estatística & dados numéricos , Pessoas sem Cobertura de Seguro de Saúde/estatística & dados numéricos , China , Feminino , Financiamento Governamental , Humanos , Modelos Logísticos , População Rural , População UrbanaRESUMO
The energy difference between a singlet exciton and twice of a triplet exciton, ΔESF, provides the thermodynamic driving force for singlet exciton fission (SF). This work reports a systematic investigation on the effect of ΔESF on SF efficiency of five heteroacenes in their solutions. The low-temperature, near-infrared phosphorescence spectra gave the energy levels of the triplet excitons, allowing us to identify the values of ΔESF, which are -0.58, -0.34, -0.31, -0.32, and -0.34 eV for the thiophene, benzene, pyridine, and two tetrafluorobenzene terminated molecules, respectively. Corresponding SF efficiencies of the five heteroacenes in 0.02 M solutions were determined via femtosecond transient absorption spectroscopy to be 117%, 124%, 140%, 132%, and 135%, respectively. This result reveals that higher ΔESF is not, as commonly expected, always beneficial for higher SF efficiency in solution phase. On the contrary, excessive exoergicity results in reduction of SF efficiency in the heteroacenes due to the promotion of other competitive exciton relaxation pathways. Therefore, it is important to optimize thermodynamic driving force when designing organic materials for high SF efficiency.
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Valproate exposure is associated with increased risks of autism spectrum disorder. To date, the mechanistic details of disturbance of melatonin receptor subtype 1 (MTNR1A) internalization upon valproate exposure remain elusive. By expressing epitope-tagged receptors (MTNR1A-EGFP) in HEK-293 and Neuro-2a cells, we recorded the dynamic changes of MTNR1A intracellular trafficking after melatonin treatment. Using time-lapse confocal microscopy, we showed in living cells that valproic acid interfered with the internalization kinetics of MTNR1A in the presence of melatonin. This attenuating effect was associated with a decrease in the phosphorylation of PKA (Thr197) and ERK (Thr202/Tyr204). VPA treatment did not alter the whole-cell currents of cells with or without melatonin. Furthermore, fluorescence resonance energy transfer imaging data demonstrated that valproic acid reduced the melatonin-initiated association between YFP-labeled ß-arrestin 2 and CFP-labeled MTNR1A. Together, we suggest that valproic acid influences MTNR1A intracellular trafficking and signaling in a ß-arrestin 2-dependent manner.
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Espaço Intracelular/metabolismo , Receptor MT1 de Melatonina/metabolismo , Transdução de Sinais/efeitos dos fármacos , Ácido Valproico/farmacologia , beta-Arrestinas/metabolismo , Animais , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Endocitose/efeitos dos fármacos , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Transferência Ressonante de Energia de Fluorescência , Células HEK293 , Humanos , Melatonina/farmacologia , Camundongos , Fosforilação/efeitos dos fármacos , Ligação Proteica/efeitos dos fármacos , Transporte Proteico/efeitos dos fármacos , Proteínas rab de Ligação ao GTP/metabolismoRESUMO
We report the in vivo distribution, toxicity and metabolism of micro-sized fluorescent organic particles and their applications in cerebral blood flow tracing. The fluorescent microparticles exhibit bright fluorescence, good photo-stability and low toxicity; therefore, they are ideal for long-term non-invasive in vivo tracing. In contrast to conventional fluorescent labeling agents, which stain the entire blood vessel, the tracer microparticles can be easily tracked individually and provide vital information about blood flow behavior. Furthermore, we observed stimulated emission from these microparticles in living animals. These microparticles can provide unprecedented contrast for simultaneous observation of the distribution of blood vessels and the dynamics of microcirculation. Pathological examination revealed that the injected microparticles eventually collected in the spleen and liver. We found no observable toxicity of the microparticles to cells or mouse organs. We demonstrate that these fluorescent microparticles are suitable for applications in the field of non-intrusive blood flow tracing and could play a complementary role to traditional imaging agents.
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OBJECTIVE: To evaluate the performance of locked nucleic acid (LNA) probe Real-time polymerase chain reaction (PCR) in the detection of Aspergillus fumigatus (A. fumigatus). METHODS: All clinically cultured isolates of Aspergillus at our hospital were identified by morphology and DNA sequencing assay. The experimental group consists of A. fumigatus (n = 48) while the control group was made up of A. flavus (n = 55), A. versicolor (n = 16), A. nidulans (n = 10), A. sydowii (n = 5) and A. parasiticus (n = 1). The clinical samples consisted of A. fumigatus sinusitis tissue (n = 20) and bronchoalveolar lavage fluid (n = 1). DNA was extracted from all samples. A. fumigatus ß-tubulin gene was targeted with LNA probe Real-time PCR assay. LNA probe Real-time PCR was evaluated with regards to specificity, efficiency, linear dynamic range in PCR amplification and limits of detection. RESULTS: All clinical samples were positively amplified. The specificity was 100% and the PCR efficiency 98.2%. Linear dynamic range was at least six orders of magnitude and the limit of detection 2.5 pg. CONCLUSION: LNA probe Real-time PCR is a promisingly accurate assay of rapidly detecting A. fumigatus practically and cost-efficiently.